| 1. |
- Avigo, R., et al.
(författare)
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Low-lying electric dipole gamma-continuum for the unstable Fe-62,64 nuclei : Strength evolution with neutron number
- 2020
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Ingår i: Physics Letters B. - : ELSEVIER. - 0370-2693 .- 1873-2445. ; 811
-
Tidskriftsartikel (refereegranskat)abstract
- The gamma-ray emission from the nuclei Fe-62,Fe-64 following Coulomb excitation at bombarding energy of 400-440 AMeV was measured with special focus on E1 transitions in the energy region 4-8 MeV. The unstable neutron-rich nuclei Fe-62,Fe-64 were produced at the FAIR-GSI laboratories and selected with the FRS spectrometer. The gamma decay was detected with AGATA. From the measured gamma-ray spectra the summed E1 strength is extracted and compared to microscopic quasi-particle phonon model calculations. The trend of the E1 strength with increasing neutron number is found to be fairly well reproduced with calculations that assume a rather complex structure of the 1(-) states (three-phonon states) inducing a strong fragmentation of the E1 nuclear response below the neutron binding energy.
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| 2. |
- Bernal, Ximena E., et al.
(författare)
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Empowering Latina scientists
- 2019
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 363:6429, s. 825-826
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 3. |
- Fonseca Quintana, Magilé C., et al.
(författare)
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Caracterización molecular del CVA24v aislado en Cuba duran-te 23 años, 1986-2003, revela hallazgos en la epidemiología y patogenia del virus
- 2023
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Ingår i: Anales de la Academia de Ciencias de Cuba. - 2304-0106. ; 13:3
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: The CVA24 antigenic variant is the causal agent of epidemics of acute hemorrhagic conjunctivitis that has prevailed to date. To study the transmission dynamics and evolution of this variant, we molecularly characterized Cuban isolates obtained in 5 epidemic periods between 1986 and 2009. Methods: Using the BEAST v1.8.4 program, it was performed the phylogenetic and phylodynamic analysis of the partial genomic regions of 54 Cuban sequences and 83 sequences from 17 countries for the 3C genomic region and 35 Cuban sequences with 95 sequences from 18 countries for the VP1 region. They were analyzed the amino acid changes of the Cuban sequences and they were compared the sequences obtained from conjunctival exudates and feces. Results: It was identified that each epidemic period was caused by different genetic variants, and homologous to variants that circulated in the Americas, Africa, and Asia, and that could circulate up to 2 years prior to the epidemic peaks. The virus showed a stable effective population over time, increasing in pandemic periods, with a nucleotide substitution rate (substitutions/site/year) of 4.39 × 10-3 for the 3C region and 5.80 × 10-3 for VP1. They were obtained 19 viral transmission routes for the 3C genomic region and 25 routes for VP1. They were inferred the routes of introduction of the virus to Cuba in the epidemic periods of the years 1986, 1997, 2003 and 2008-2009 by the ancestral relationships of the Cuban sequences with sequences of destination countries of some routes, endorsed by viral transmission networks. Amino acid changes in both genomic regions could be involved in the evolution of CVA24v and it was obtained evidence that supports the use of feces to identify this viral variant. The conclusions were new knowledge in the molecular epidemiology of CVA24v that circulated in Cuba and the world for 23 years after its global emergence.
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| 4. |
- Rivera-Ramos, Alberto, et al.
(författare)
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Galectin-3 depletion tames pro-tumoural microglia and restrains cancer cells growth
- 2024
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Ingår i: Cancer Letters. - 0304-3835. ; 591
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Tidskriftsartikel (refereegranskat)abstract
- Galectin-3 (Gal-3) is a multifunctional protein that plays a pivotal role in the initiation and progression of various central nervous system diseases, including cancer. Although the involvement of Gal-3 in tumour progression, resistance to treatment and immunosuppression has long been studied in different cancer types, mainly outside the central nervous system, its elevated expression in myeloid and glial cells underscores its profound impact on the brain's immune response. In this context, microglia and infiltrating macrophages, the predominant non-cancerous cells within the tumour microenvironment, play critical roles in establishing an immunosuppressive milieu in diverse brain tumours. Through the utilisation of primary cell cultures and immortalised microglial cell lines, we have elucidated the central role of Gal-3 in promoting cancer cell migration, invasion, and an immunosuppressive microglial phenotypic activation. Furthermore, employing two distinct in vivo models encompassing primary (glioblastoma) and secondary brain tumours (breast cancer brain metastasis), our histological and transcriptomic analysis show that Gal-3 depletion triggers a robust pro-inflammatory response within the tumour microenvironment, notably based on interferon-related pathways. Interestingly, this response is prominently observed in tumour-associated microglia and macrophages (TAMs), resulting in the suppression of cancer cells growth.
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| 5. |
- Singh, Tania, et al.
(författare)
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Loss of MafA and MafB expression promotes islet inflammation.
- 2019
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 9:1
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Tidskriftsartikel (refereegranskat)abstract
- Maf transcription factors are critical regulators of beta-cell function. We have previously shown that reduced MafA expression in human and mouse islets is associated with a pro-inflammatory gene signature. Here, we investigate if the loss of Maf transcription factors induced autoimmune processes in the pancreas. Transcriptomics analysis showed expression of pro-inflammatory as well as immune cell marker genes. However, clusters of CD4+ T and B220+ B cells were associated primarily with adult MafA-/-MafB+/-, but not MafA-/- islets. MafA expression was detected in the thymus, lymph nodes and bone marrow suggesting a novel role of MafA in regulating immune-cell function. Analysis of pancreatic lymph node cells showed activation of CD4+ T cells, but lack of CD8+ T cell activation which also coincided with an enrichment of naïve CD8+ T cells. Further analysis of T cell marker genes revealed a reduction of T cell receptor signaling gene expression in CD8, but not in CD4+ T cells, which was accompanied with a defect in early T cell receptor signaling in mutant CD8+ T cells. These results suggest that loss of MafA impairs both beta- and T cell function affecting the balance of peripheral immune responses against islet autoantigens, resulting in local inflammation in pancreatic islets.
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| 6. |
- Singh, Tania, et al.
(författare)
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MafA expression preserves immune homeostasis in human and mouse islets
- 2018
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Ingår i: Genes. - : MDPI AG. - 2073-4425. ; 9:12
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Tidskriftsartikel (refereegranskat)abstract
- Type 1 (T1D) and type 2 (T2D) diabetes are triggered by a combination of environmental and/or genetic factors. Maf transcription factors regulate pancreatic beta (β)-cell function, and have also been implicated in the regulation of immunomodulatory cytokines like interferon-β (IFNβ1). In this study, we assessed MAFA and MAFB co-expression with pro-inflammatory cytokine signaling genes in RNA-seq data from human pancreatic islets. Interestingly, MAFA expression was strongly negatively correlated with cytokine-induced signaling (such as IFNAR1, DDX58) and T1D susceptibility genes (IFIH1), whereas correlation of these genes with MAFB was weaker. In order to evaluate if the loss of MafA altered the immune status of islets, MafA deficient mouse islets (MafA−/−) were assessed for inherent anti-viral response and susceptibility to enterovirus infection. MafA deficient mouse islets had elevated basal levels of Ifnβ1, Rig1 (DDX58 in humans), and Mda5 (IFIH1) which resulted in reduced virus propagation in response to coxsackievirus B3 (CVB3) infection. Moreover, an acute knockdown of MafA in β-cell lines also enhanced Rig1 and Mda5 protein levels. Our results suggest that precise regulation of MAFA levels is critical for islet cell-specific cytokine production, which is a critical parameter for the inflammatory status of pancreatic islets.
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| 7. |
- Alexander, T., et al.
(författare)
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Isomeric Ratios in 206Hg
- 2015
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Ingår i: Acta Physica Polonica. Series B: Elementary Particle Physics, Nuclear Physics, Statistical Physics, Theory of Relativity, Field Theory. - 0587-4254. ; 46:3, s. 601-605
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Tidskriftsartikel (refereegranskat)abstract
- Hg-206 was populated in the fragmentation of an E/A = 1 GeV Pb-208 beam at GSI. It was part of a campaign to study nuclei around Pb-208 via relativistic Coulomb excitation. The observation of the known isomeric states confirmed the identification of the fragmentation products. The isomeric decays were also used to prove that the correlations between beam identification detectors and the AGATA gamma-ray tracking array worked properly and that the tracking efficiency was independent of the time relative to the prompt flash.
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| 8. |
- Arndt, D. S., et al.
(författare)
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State of the Climate in 2016
- 2017
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Ingår i: Bulletin of The American Meteorological Society - (BAMS). - 0003-0007 .- 1520-0477. ; 98:8, s. S1-S280
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Tidskriftsartikel (refereegranskat)abstract
- In 2016, the dominant greenhouse gases released into Earth's atmosphere-carbon dioxide, methane, and nitrous oxide-continued to increase and reach new record highs. The 3.5 +/- 0.1 ppm rise in global annual mean carbon dioxide from 2015 to 2016 was the largest annual increase observed in the 58-year measurement record. The annual global average carbon dioxide concentration at Earth's surface surpassed 400 ppm (402.9 +/- 0.1 ppm) for the first time in the modern atmospheric measurement record and in ice core records dating back as far as 800000 years. One of the strongest El Nino events since at least 1950 dissipated in spring, and a weak La Nina evolved later in the year. Owing at least in part to the combination of El Nino conditions early in the year and a long-term upward trend, Earth's surface observed record warmth for a third consecutive year, albeit by a much slimmer margin than by which that record was set in 2015. Above Earth's surface, the annual lower troposphere temperature was record high according to all datasets analyzed, while the lower stratospheric temperature was record low according to most of the in situ and satellite datasets. Several countries, including Mexico and India, reported record high annual temperatures while many others observed near-record highs. A week-long heat wave at the end of April over the northern and eastern Indian peninsula, with temperatures surpassing 44 degrees C, contributed to a water crisis for 330 million people and to 300 fatalities. In the Arctic the 2016 land surface temperature was 2.0 degrees C above the 1981-2010 average, breaking the previous record of 2007, 2011, and 2015 by 0.8 degrees C, representing a 3.5 degrees C increase since the record began in 1900. The increasing temperatures have led to decreasing Arctic sea ice extent and thickness. On 24 March, the sea ice extent at the end of the growth season saw its lowest maximum in the 37-year satellite record, tying with 2015 at 7.2% below the 1981-2010 average. The September 2016 Arctic sea ice minimum extent tied with 2007 for the second lowest value on record, 33% lower than the 1981-2010 average. Arctic sea ice cover remains relatively young and thin, making it vulnerable to continued extensive melt. The mass of the Greenland Ice Sheet, which has the capacity to contribute similar to 7 m to sea level rise, reached a record low value. The onset of its surface melt was the second earliest, after 2012, in the 37-year satellite record. Sea surface temperature was record high at the global scale, surpassing the previous record of 2015 by about 0.01 degrees C. The global sea surface temperature trend for the 21st century-to-date of +0.162 degrees C decade(-1) is much higher than the longer term 1950-2016 trend of +0.100 degrees C decade(-1). Global annual mean sea level also reached a new record high, marking the sixth consecutive year of increase. Global annual ocean heat content saw a slight drop compared to the record high in 2015. Alpine glacier retreat continued around the globe, and preliminary data indicate that 2016 is the 37th consecutive year of negative annual mass balance. Across the Northern Hemisphere, snow cover for each month from February to June was among its four least extensive in the 47-year satellite record. Continuing a pattern below the surface, record high temperatures at 20-m depth were measured at all permafrost observatories on the North Slope of Alaska and at the Canadian observatory on northernmost Ellesmere Island. In the Antarctic, record low monthly surface pressures were broken at many stations, with the southern annular mode setting record high index values in March and June. Monthly high surface pressure records for August and November were set at several stations. During this period, record low daily and monthly sea ice extents were observed, with the November mean sea ice extent more than 5 standard deviations below the 1981-2010 average. These record low sea ice values contrast sharply with the record high values observed during 2012-14. Over the region, springtime Antarctic stratospheric ozone depletion was less severe relative to the 1991-2006 average, but ozone levels were still low compared to pre-1990 levels. Closer to the equator, 93 named tropical storms were observed during 2016, above the 1981-2010 average of 82, but fewer than the 101 storms recorded in 2015. Three basins-the North Atlantic, and eastern and western North Pacific-experienced above-normal activity in 2016. The Australian basin recorded its least active season since the beginning of the satellite era in 1970. Overall, four tropical cyclones reached the Saffir-Simpson category 5 intensity level. The strong El Nino at the beginning of the year that transitioned to a weak La Nina contributed to enhanced precipitation variability around the world. Wet conditions were observed throughout the year across southern South America, causing repeated heavy flooding in Argentina, Paraguay, and Uruguay. Wetter-than-usual conditions were also observed for eastern Europe and central Asia, alleviating the drought conditions of 2014 and 2015 in southern Russia. In the United States, California had its first wetter-than-average year since 2012, after being plagued by drought for several years. Even so, the area covered by drought in 2016 at the global scale was among the largest in the post-1950 record. For each month, at least 12% of land surfaces experienced severe drought conditions or worse, the longest such stretch in the record. In northeastern Brazil, drought conditions were observed for the fifth consecutive year, making this the longest drought on record in the region. Dry conditions were also observed in western Bolivia and Peru; it was Bolivia's worst drought in the past 25 years. In May, with abnormally warm and dry conditions already prevailing over western Canada for about a year, the human-induced Fort McMurray wildfire burned nearly 590000 hectares and became the costliest disaster in Canadian history, with $3 billion (U.S. dollars) in insured losses.
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| 9. |
- Barchetta, Ilaria, et al.
(författare)
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Epigenetic changes induced by maternal factors during fetal life : Implication for type 1 diabetes
- 2021
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Ingår i: Genes. - : MDPI AG. - 2073-4425. ; 12:6
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Forskningsöversikt (refereegranskat)abstract
- Organ-specific autoimmune diseases, such as type 1 diabetes, are believed to result from T-cell-mediated damage of the target tissue. The immune-mediated tissue injury, in turn, is known to depend on complex interactions between genetic and environmental factors. Nevertheless, the mechanisms whereby environmental factors contribute to the pathogenesis of autoimmune diseases remain elusive and represent a major untapped target to develop novel strategies for disease prevention. Given the impact of the early environment on the developing immune system, epigenetic changes induced by maternal factors during fetal life have been linked to a likelihood of developing an autoimmune disease later in life. In humans, DNA methylation is the epigenetic mechanism most extensively investigated. This review provides an overview of the critical role of DNA methylation changes induced by prenatal maternal conditions contributing to the increased risk of immune-mediated diseases on the offspring, with a particular focus on T1D. A deeper understanding of epigenetic alterations induced by environmental stressors during fetal life may be pivotal for developing targeted prevention strategies of type 1 diabetes by modifying the maternal environment.
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| 10. |
- Böhm, Paul, et al.
(författare)
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Search for Weak Side Branches in the Electromagnetic Decay Paths of the 6526-keV 10+ Isomer in 54Fe
- 2023
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Ingår i: Atoms. - 2218-2004. ; 11:9
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Tidskriftsartikel (refereegranskat)abstract
- High-spin nuclear isomers in N≈Z nuclei between doubly magic 40Ca and 56Ni provide an excellent testing ground for the nuclear shell model and questions related to isospin symmetry breaking in the vicinity of the proton drip line. The purpose of the present study is to investigate the possibility of weak electromagnetic decay branches along the decay paths of the 6526-keV 10+ isomer in 54Fe. The isomer was strongly populated by means of the fusion-evaporation reaction 24Mg(36Ar,α2p)54?Fe. The Gammasphere array was used to detect γ-ray cascades emitted from the isomeric state. By means of γγγ coincidences, weak non-yrast decay branches can be discriminated, with the isomer’s half-life confirmed at T1/2 =363(4) ns. The yrast 6+1→2+1 E4 cross-over transition was interrogated. The observations are compared with shell-model calculations.
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| 11. |
- Cabrera-Rode, Eduardo, et al.
(författare)
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An Exploratory Study of Itolizumab on the Preservation of Beta Cell Function in Adults with Recent-Onset Type 1 Diabetes
- 2022
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Ingår i: Journal of Clinical Medicine. - : MDPI AG. - 2077-0383. ; 11:7
-
Tidskriftsartikel (refereegranskat)abstract
- We conducted a phase I-IIa, randomized, monocentric, double-blind, placebo-controlled clinical trial to evaluate the safety and impact of the combination treatment of Itolizumab and insulin on preserving beta cell function in adults with recent-onset type 1 diabetes. Twelve patients were randomly assigned to three treatment groups, each receiving a different Itolizumab dose (0.4/0.8/1.6 mg/kg body weight, respectively) and a placebo group. All patients received concomitant intensive multiple-dose insulin therapy. Endogenous insulin secretion was assessed by the measurement of C-peptide during the mixed-meal tolerance test. No serious adverse events were reported. No changes in the total daily insulin doses, glycated hemoglobin levels, and stimulated C-peptide were observed between the Itolizumab and placebo groups at 52 weeks. A significant decrease in stimulated C-peptide was observed during the follow-up period (p = 0.012). One subject treated with 1.6 mg of Itolizumab showed a marked increase in the levels of stimulated C-peptide three years after completion of the trial. Taken together, this is the first study to demonstrate that combination treatment with Itolizumab and insulin is safe in humans and does not affect the residual function of beta cells up to 52 weeks. The findings from our study show preliminary evidence that high doses of Itolizumab could potentially arrest the loss of beta cell function in the long term. Further studies with a longer follow-up and larger numbers of patients are envisaged to assess the effect with high dose Itolizumab.
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| 12. |
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| 13. |
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| 14. |
- Duquesne, Amílcar, et al.
(författare)
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Diagnostic Testing Accuracy for Helicobacter pylori Infection among Adult Patients with Dyspepsia in Cuba’s Primary Care Setting
- 2023
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Ingår i: Microorganisms. - 2076-2607. ; 11:4
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Tidskriftsartikel (refereegranskat)abstract
- Evidence of the effectiveness of the tests used to diagnose Helicobacter pylori (H. pylori) in primary healthcare is limited. This cross-sectional study aims to assess the accuracy of tests used for to diagnose H. pylori infection in primary care patients and its relationship with gastroduodenal pathologies. Over 12 months, 173 primary care patients with dyspeptic symptoms were referred for upper gastrointestinal endoscopy to obtain gastric biopsies, and venous blood was extracted from them. H. pylori infection was detected using a rapid urease test (RUT), real-time polymerase chain reaction (RT-PCR), H. pylori-IgG ELISA, and Western blot (WB). The culture and histological findings were used as the reference standard for H. pylori infection. H. pylori prevalence was 50%. There were no significant differences between men and women overall or by age group. The presence of H. pylori was associated with chronic moderate gastritis and its absence with chronic inactive gastritis, as well as the combination of gastritis and gastric lesions (p < 0.05). RUT and ELISA H. pylori -IgG tests showed the highest overall performance (accuracy 98.9% and 84.4%), followed by WB and RT-PCR (accuracy 79.3% and 73.9%). These findings support the notion that combined invasive and noninvasive methods, such as RUT and H. pylori-IgG ELISA, can be a primary diagnostic screening tool for detecting H. pylori among adult dyspeptic patients in Cuba’s primary care setting.
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| 15. |
- Fonseca, M. C., et al.
(författare)
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Molecular Characterization of Coxsackievirus A24v from Feces and Conjunctiva Reveals Epidemiological Links
- 2021
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Ingår i: Microorganisms. - : MDPI AG. - 2076-2607. ; 9:3
-
Tidskriftsartikel (refereegranskat)abstract
- Coxsackievirus A24 variant (CVA24v), the main causative agent of acute hemorrhagic conjunctivitis (AHC), can be isolated from both the eyes and lower alimentary tract. However, the molecular features of CVA24v in feces is not well-documented. In this study, we compared the VP1 and 3C sequences of CVA24v strains isolated from feces during AHC epidemics in Cuba in 1997, 2003, and 2008-2009 with those obtained from conjunctival swabs during the same epidemic period. The sequence analyses of the 3C and VP1 region of stool isolates from the three epidemics showed a high degree of nucleotide identity (ranging from 97.3-100%) to the corresponding conjunctival isolates. The phylogenetic analysis showed that fecal CVA24v isolates from the 1997 and 2003 Cuban outbreaks formed a clade with CVA24v strains isolated from conjunctival swabs in Cuba and other countries during the same period. There were three amino acid changes (3C region) and one amino acid change (VP1 region) in seven CVA24v strains isolated sequentially over 20 days from fecal samples of one patient, suggesting viral replication in the intestine. Despite these substitutions, the virus from the conjunctival swab and fecal samples were genetically very similar. Therefore, fecal samples should be considered as a reliable alternative sample type for the routine molecular diagnosis and molecular epidemiology of CVA24v, also during outbreaks of AHC.
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| 16. |
- Fonseca, M. C., et al.
(författare)
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Molecular evolution of coxsackievirus A24v in Cuba over 23-years, 1986-2009
- 2020
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 10:1
-
Tidskriftsartikel (refereegranskat)abstract
- Coxsackievirus A24 variant (CVA24v) is a major causative agent of acute hemorrhagic conjunctivitis outbreaks worldwide, yet the evolutionary and transmission dynamics of the virus remain unclear. To address this, we analyzed and compared the 3C and partial VP1 gene regions of CVA24v isolates obtained from five outbreaks in Cuba between 1986 and 2009 and strains isolated worldwide. Here we show that Cuban strains were homologous to those isolated in Africa, the Americas and Asia during the same time period. Two genotypes of CVA24v (GIII and GIV) were repeatedly introduced into Cuba and they arose about two years before the epidemic was detected. The two genotypes co-evolved with a population size that is stable over time. However, nucleotide substitution rates peaked during pandemics with 4.39x10(-3) and 5.80x10(-3) substitutions per site per year for the 3C and VP1 region, respectively. The phylogeographic analysis identified 25 and 19 viral transmission routes based on 3C and VP1 regions, respectively. Pandemic viruses usually originated in Asia, and both China and Brazil were the major hub for the global dispersal of the virus. Together, these data provide novel insight into the epidemiological dynamics of this virus and possibly other pandemic viruses.
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| 17. |
- Forsberg, Ulrika, et al.
(författare)
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Spectroscopic Tools Applied to Element Z = 115 Decay Chains
- 2014
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Ingår i: EPJ Web of Conferences. - : EDP Sciences. - 2100-014X .- 2101-6275. - 9782759811755 - 9782759811762 ; 66, s. 02036-02036
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Konferensbidrag (refereegranskat)abstract
- Nuclides that are considered to be isotopes of element Z = 115 were produced in the reaction 48Ca + 243Am at the GSI Helmholtzzentrum für Schwerionenforschung Darmstadt. The detector setup TASISpec was used. It was mounted behind the gas-filled separator TASCA. Thirty correlated α-decay chains were found, and the energies of the particles were determined with high precision. Two important spectroscopic aspects of the offline data analysis are discussed in detail: the handling of digitized preamplified signals from the silicon strip detectors, and the energy reconstruction of particles escaping to upstream detectors relying on pixel-by-pixel dead-layer thicknesses.
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| 18. |
- Gates, J. M., et al.
(författare)
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Decay Spectroscopy of Element 115 Daughters: 280Rg -> 276Mt and 276Mt -> 272Bh
- 2015
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Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 92:2
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Tidskriftsartikel (refereegranskat)abstract
- Forty-six decay chains, assigned to the decay of 288-115, were produced using the 243Am(48Ca,3n)288-115 reaction at the Lawrence Berkeley National Laboratory 88-in. cyclotron. The resulting series of α decays were studied using α-photon and α-x-ray spectroscopies. Multiple α-photon coincidences were observed in the element 115 decay chain members, particularly in the third- and fourth-generation decays (presumed to be 280Rg and 276Mt, respectively). Upon combining these data with those from 22 288-115 decay chains observed in a similar experiment, updated level schemes in 276Mt and 272Bh (populated by the α decay of 280Rg and 276Mt, respectively) are proposed. Photons were observed in the energy range expected for K x rays coincident with the α decay of both 280Rg and 276Mt. However, Compton scattering of higher-energy γ rays and discrete transitions are present in the K x-ray region preventing a definitive Z identification to be made based on observation of characteristic K x-ray energies.
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| 19. |
- González-De Schroeder, María Mercedes, et al.
(författare)
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Vigilancia ambiental de la circulación de poliovirus en tres municipios considerados como punto transitorio de migrantes en Colombia 2017-2019
- 2022
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Ingår i: Infectio. - : Asociacion Colombiana de Infectologia - ACIN. - 0123-9392 .- 2422-3794. ; 26:2, s. 107-112
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To determine the circulation of poliovirus in three municipalities considered as transitory points for migrants in Colombia. Material and Method: Wastewater samples (n = 36) were collected from border municipalities, selected for greater transit of regular and irregular migrants, in the period between 2017-2019. The samples were concentrated and cultured following the World Health Organization (WHO) environmental surveillance algorithm for poliovirus circulation. Molecular identification was performed by polymerase chain reaction using group-specific, serotype and sabin vaccine strain primers. Results: The presence of non-polio Enterovirus (NPV) was detected in the environmental samples obtained and no circulation of poliovirus derived from the vaccine or wild poliovirus was found in the three evaluated municipalities; However, in two previous studies published by Gonzales et al with a similar methodology in 2005 and 2015 evaluating the wastewater of the city of Armenia-Quindío; It was possible to identify the presence of virus derived from vaccine, with negative results for the identification of wild poliovirus. Conclusions: The findings indicate that the wastewater monitoring system in order to determine the presence of viruses is a useful tool to carry out environmental surveillance.
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| 20. |
- González, María Mercedes, et al.
(författare)
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Environmental surveillance of polioviruses in armenia, Colombia before trivalent oral polio vaccine cessation
- 2019
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Ingår i: Viruses. - : MDPI AG. - 1999-4915. ; 11:9
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Tidskriftsartikel (refereegranskat)abstract
- Although acute flaccid paralysis (AFP) surveillance is the “gold standard” for detecting cases of polio, environmental surveillance can provide supplementary information in the absence of paralytic poliomyelitis cases. This study aimed to detect the introduction and/or circulation of wild poliovirus or vaccine-derived polioviruses (VDPV) in wastewater, covering a significant population of Armenia, Colombia, before trivalent oral polio vaccine (OPV) cessation. Between March and September 2015, 24 wastewater samples were collected from eight study sites in eight communes of Armenia, Colombia. Virus detection and characterization were performed using both cell culture (i.e., RD or L20B cells) and RT-PCR. Polioviruses were isolated in 11 (45.8%) of 24 wastewater samples. All isolates were identified as Sabin strains (type 1 = 9, type 3 = 2) by intratypic differentiation. Type 2 poliovirus was not detected in any of the samples. No wild poliovirus or VDPV was detected among the isolates. Non-polio enterovirus was identified in 8.3% (2/24) of the samples. This study revealed the excretion of Sabin poliovirus from OPV-immunized individuals, as well as the absence of VDPV and wild poliovirus in wastewaters of Armenia, Colombia. This confirms that environmental surveillance is an effective method, as an additional support to AFP surveillance, to monitor poliovirus during the OPV-to-IPV (inactivated polio vaccine) transition period.
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| 21. |
- González, María M., et al.
(författare)
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Seroprevalencia de anticuerpos a virus del sarampión, rubeola, parotiditis, hepatitis B y los tres serotipos de poliovirus, en niños de Quindío, Colombia
- 2016
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Ingår i: Revista de Salud Publica. - : Universidad Nacional de Colombia. - 0124-0064. ; 18:1, s. 95-103
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Tidskriftsartikel (refereegranskat)abstract
- Objective: The main goal of this research was to assess the seroprevalence of antibodies against measles, rubella, mumps, hepatitis B and all three poliovirus serotypes among children in the Quindio Department, Colombia. Methods: Blood samples were obtained from 170 healthy children aged 5-9 years from nine municipalities in Quindio. The presence of serum IgG antibodies against measles, rubella, mumps and Hepatitis B were determined using commercial indirect ELISA kits. Immunity to poliomyelitis was assessed through the presence of neutralizing antibodies following the method recommended by the World Health Organization. Results: Among the 170 children enrolled, 169 (99.41%), 170(100 %), and 167 (98.2 %) were seropositive to poliovirus 1, poliovirus 2, and poliovirus 3, respectively. The average reciprocal antibody titers were 178 for poliovirus type 1, 120 for type 2 and 56 for type 3. Of the 170 children, 96.47 % were protected against mumps and rubella, and 86.47 % against measles. Only 106 (62.35 %) of the studied subjects were proved to be seropositive to hepatitis B. Conclusion: The immunization program in Quindio has provided seroprotection against all three poliomyelitis serotypes, rubella and mumps. However, the child population is not fully protected against measles and hepatitis B virus infections.
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| 22. |
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| 23. |
- Hrabar, Yuliia, et al.
(författare)
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Anti-Compton shield for Compex germanium detector modules
- 2023
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Ingår i: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0168-9002. ; 1056
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Tidskriftsartikel (refereegranskat)abstract
- A bismuth-germanate (BGO) anti-Compton shield (ACS) for Compex germanium detector modules was designed, built, and characterised. BGO performance was evaluated for light output and energy resolution. The response of the ACS shield and its impact on germanium detector spectra was measured for standard 60Co, 133Ba, and 137Cs sources. The results were compared to comprehensive Geant4 simulations. The ~70% improvement of the peak-to-total ratio for the 137Cs 662-keV γ-ray peak is in good agreement with expectations from the simulations. A 133Ba source exemplifies decay schemes of odd-A superheavy nuclei. Congruence between measured and simulated spectra indicates that the Compex plus ACS multi-detector module is well understood.
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| 24. |
- Jin, S. Y., et al.
(författare)
-
Spectroscopy of 98Cd by two-nucleon removal from 100In
- 2021
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Ingår i: Physical Review C: covering nuclear physics. - 2469-9985. ; 104:2
-
Tidskriftsartikel (refereegranskat)abstract
- Low-lying states of Cd-98 have been populated by the two-nucleon removal reaction (In-100, Cd-98+gamma) and studied using in-beam gamma-ray spectroscopy at the Radioactive Isotope Beam Factory at RIKEN. Two new gamma transitions were identified and assigned as decays from a previously unknown state. This state is suggested to be based on a pi 1g(/9/2)(-1)2p(1/2)(-2) configuration with J(pi) = 5(-). The present observation extends the systematics of the excitation energies of the first 5(-) state in N = 50 isotones toward Sn-100. The determined energy of the 5(- )state in Cd-98 continues a smooth trend along the N = 50 isotones. The systematics are compared with shell-model calculations in different model spaces. Good agreement is achieved when considering a model space consisting of the pi(1f(5/2), 2p(3/2), 2p(1/2), 1g(9/2)) orbitals. The calculations with a smaller model space omitting the orbitals below the Z = 38 subshell could not reproduce the experimental energy difference between the ground and first 5(-) states in N = 50 isotones, because proton excitations across Z = 38 subshell yield a large amount of correlation energy that lowers the ground states.
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| 25. |
- Khuyagbaatar, J., et al.
(författare)
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48Ca+249Bk Fusion Reaction Leading to Element Z=117: Long-Lived α-Decaying 270Db and Discovery of 266Lr
- 2014
-
Ingår i: Physical Review Letters. - 1079-7114. ; 112:17
-
Tidskriftsartikel (refereegranskat)abstract
- The superheavy element with atomic number Z=117 was produced as an evaporation residue in the 48Ca+249Bk fusion reaction at the gas-filled recoil separator TASCA at GSI Darmstadt, Germany. The radioactive decay of evaporation residues and their α-decay products was studied using a detection setup that allowed measuring decays of single atomic nuclei with half-lives between sub-μs and a few days. Two decay chains comprising seven α decays and a spontaneous fission each were identified and are assigned to the isotope 294-117 and its decay products. A hitherto unknown α-decay branch in 270Db (Z=105) was observed, which populated the new isotope 266Lr (Z=103). The identification of the long-lived (T1/2=1.0+1.9−0.4 h) α-emitter 270Db marks an important step towards the observation of even more long-lived nuclei of superheavy elements located on an “island of stability.”
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| 26. |
- Khuyagbaatar, J., et al.
(författare)
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New Short-Lived Isotope 221U and the Mass Surface Near N=126
- 2015
-
Ingår i: Physical Review Letters. - 1079-7114. ; 115:24
-
Tidskriftsartikel (refereegranskat)abstract
- Two short-lived isotopes 221U and 222U were produced as evaporation residues in the fusion reaction 50Ti+176Yb at the gas-filled recoil separator TASCA. An α decay with an energy of Eα=9.31(5) MeV and half-life T1/2=4.7(7) μs was attributed to 222U. The new isotope 221U was identified in α-decay chains starting with Eα=9.71(5) MeV and T1/2=0.66(14) μs leading to known daughters. Synthesis and detection of these unstable heavy nuclei and their descendants were achieved thanks to a fast data readout system. The evolution of the N=126 shell closure and its influence on the stability of uranium isotopes are discussed within the framework of α-decay reduced width.
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| 27. |
- Khuyagbaatar, J., et al.
(författare)
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Search for elements 119 and 120
- 2020
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Ingår i: Physical Review C. - 2469-9985. ; 102:6
-
Tidskriftsartikel (refereegranskat)abstract
- A search for production of the superheavy elements with atomic numbers 119 and 120 was performed in the 50Ti+249Bk and 50Ti+249Cf fusion-evaporation reactions, respectively, at the gas-filled recoil separator TASCA at GSI Darmstadt, Germany. Over four months of irradiation, the 249Bk target partially decayed into 249Cf, which allowed for a simultaneous search for both elements. Neither was detected at cross-section sensitivity levels of 65 and 200 fb for the 50Ti+249Bk and 50Ti+249Cf reactions, respectively, at a midtarget beam energy of Elab = 281.5 MeV. The nonobservation of elements 119 and 120 is discussed within the concept of fusion-evaporation reactions including various theoretical predictions on the fission-barrier heights of superheavy nuclei in the region of the island of stability.
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| 28. |
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| 29. |
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| 30. |
- Lalović, Nataša, et al.
(författare)
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Study of isomeric states in 198,200,202,206Pb and 206Hg populated in fragmentation reactions
- 2018
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Ingår i: Journal of Physics G: Nuclear and Particle Physics. - : IOP Publishing. - 0954-3899 .- 1361-6471. ; 45:3
-
Tidskriftsartikel (refereegranskat)abstract
- Isomeric states in isotopes in the vicinity of doubly-magic 208Pb were populated following reactions of a relativistic 208Pb primary beam impinging on a 9Be fragmentation target. Secondary beams of 198,200,202,206Pb and 206Hg were isotopically separated and implanted in a passive stopper positioned in the focal plane of the GSI Fragment Separator. Delayed γ rays were detected with the Advanced Gamma Tracking Array (AGATA). Decay schemes were re-evaluated and interpreted with shell-model calculations. The momentum-dependent population of isomeric states in the two-nucleon hole nuclei 206Pb/206Hg was found to differ from the population of multi neutron-hole isomeric states in 198,200,202Pb.
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| 31. |
- Lorenz, Ch., et al.
(författare)
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Geant4-aided Quantum State Selective Decay Spectroscopy of 213Ra
- 2017
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Ingår i: The 26th International Nuclear Physics Conference. - 1824-8039. ; (INPC2016)
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Konferensbidrag (refereegranskat)abstract
- Utilizing the excellent mass resolving power of SHIPTRAP and the charged-particle-g multicoincidence setup TASISpec, the decay path of the 213Ra ground state can be exclusively studied. Based on virtual experiments with Geant4 it is possible to refine the a-branching ratios of the 213Ra ground state as well as g-ray branching ratios in the 209Rn daughter. The present study provides a proof of concept where clean quantum-state selective particle-g decay spectroscopy is used in conjunction with detailed Geant4 Monte-Carlo simulations to gain insight into nuclear structure properties.
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| 32. |
- Netanyah, Eitan, et al.
(författare)
-
Extracellular Vesicles Released by Enterovirus-Infected EndoC-βH1 Cells Mediate Non-Lytic Viral Spread
- 2020
-
Ingår i: Microorganisms. - : MDPI AG. - 2076-2607. ; 8:11
-
Tidskriftsartikel (refereegranskat)abstract
- While human enteroviruses are generally regarded as a lytic virus, and persistent non-cytolytic enterovirus infection in pancreatic beta cells has been suspected of playing a role in type 1 diabetes pathogenesis. However, it is still unclear how enteroviruses could exit the pancreatic beta cell in a non-lytic manner. This study aimed to investigate the role of beta cell-derived extracellular vesicles (EVs) in the non-lytic enteroviral spread and infection. Size-exclusion chromatography and antibody-based immunoaffinity purification were used to isolate EVs from echovirus 16-infected human beta EndoC-βH1 cells. EVs were then characterized using transmission electron microscopy and Multiplex Bead-Based Flow Cytometry Assay. Virus production and release were quantified by 50% cell culture infectious dose (CCID50) assay and qRT-PCR. Our results showed that EVs from echovirus 16-infected EndoC-βH1 cells harbor infectious viruses and promote their spread during the pre-lytic phase of infection. Furthermore, the EVs-mediated infection was not inhibited by virus-specific neutralizing antibodies. In summary, this study demonstrated that enteroviruses could exit beta cells non-lytically within infectious EVs, thereby thwarting the access of neutralizing antibodies to viral particles. These data suggest that enterovirus transmission through EVs may contribute to viral dissemination and immune evasion in persistently infected beta cells.
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| 33. |
- Radenkovic, M., et al.
(författare)
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Characterization of resident lymphocytes in human pancreatic islets
- 2017
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Ingår i: Clinical and Experimental Immunology. - : Oxford University Press (OUP). - 0009-9104 .- 1365-2249. ; 187:3, s. 418-427
-
Tidskriftsartikel (refereegranskat)abstract
- The current view of type 1 diabetes (T1D) is that it is an immune-mediated disease where lymphocytes infiltrate the pancreatic islets, promote killing of beta cells and cause overt diabetes. Although tissue resident immune cells have been demonstrated in several organs, the composition of lymphocytes in human healthy pancreatic islets have been scarcely studied. Here we aimed to investigate the phenotype of immune cells associated with human islets of non-diabetic organ donors. A flow cytometry analysis of isolated islets from perfused pancreases (n = 38) was employed to identify alpha, beta, T, natural killer (NK) and B cells. Moreover, the expression of insulin and glucagon transcripts was evaluated by RNA sequencing. Up to 80% of the lymphocytes were CD3(+) T cells with a remarkable bias towards CD8(+) cells. Central memory and effector memory phenotypes dominated within the CD8(+) and CD4(+) T cells and most CD8(+) T cells were positive for CD69 and up to 50-70% for CD103, both markers of resident memory cells. The frequency of B and NK cells was low in most islet preparations (12 and 3% of CD45(+) cells, respectively), and the frequency of alpha and beta cells varied between donors and correlated clearly with insulin and glucagon mRNA expression. In conclusion, we demonstrated the predominance of canonical tissue resident memory CD8(+) T cells associated with human islets. We believe that these results are important to understand more clearly the immunobiology of human islets and the disease-related phenotypes observed in diabetes.
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| 34. |
- Rudolph, Dirk, et al.
(författare)
-
Alpha-Photon Coincidence Spectroscopy Along Element 115 Decay Chains
- 2014
-
Ingår i: Acta Physica Polonica. Series B: Elementary Particle Physics, Nuclear Physics, Statistical Physics, Theory of Relativity, Field Theory. - 0587-4254. ; 45, s. 263-272
-
Tidskriftsartikel (refereegranskat)abstract
- Produced in the reaction 48Ca+243Am, thirty correlated α-decay chains were observed in an experiment conducted at the GSI Helmholzzentrum für Schwerionenforschung, Darmstadt, Germany. The decay chains are basically consistent with previous findings and are considered to originate from isotopes of element 115 with mass numbers 287, 288, and 289. A set-up aiming specifically for high-resolution charged particle and photon coincidence spectroscopy was placed behind the gas-filled separator TASCA. For the first time, γ rays as well as X-ray candidates were observed in prompt coincidence with the α-decay chains of element 115.
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| 35. |
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| 36. |
- Rudolph, Dirk, et al.
(författare)
-
Nuclear Structure Notes on Element 115 Decay Chains
- 2015
-
Ingår i: AIP Conference Proceedings. - : AIP Publishing LLC. - 0094-243X. - 9780735413283 ; 1681
-
Konferensbidrag (refereegranskat)abstract
- Hitherto collected data on more than hundred α-decay chains stemming from element 115 are combined to probe some aspects of the underlying nuclear structure of the heaviest atomic nuclei yet created in the laboratory.
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| 37. |
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| 38. |
- Rudolph, Dirk, et al.
(författare)
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Selected Spectroscopic Results on Element 115 Decay Chains
- 2015
-
Ingår i: Journal of Radioanalytical and Nuclear Chemistry. - : Springer Science and Business Media LLC. - 0236-5731 .- 1588-2780. ; 303:2, s. 1185-1190
-
Tidskriftsartikel (refereegranskat)abstract
- Thirty correlated alpha-decay chains were observed in an experiment studying the fusion-evaporation reaction 48Ca + 243Am at the GSI Helmholtzzentrum f¨ur Schwerionenforschung. The decay characteristics of the majority of these 30 chains are consistent with previous observations and interpretations of such chains to originate from isotopes of element Z = 115. High-resolution alpha-photon coincidence spectroscopy in conjunction with comprehensive Monte-Carlo simulations allow to propose excitation schemes of atomic nuclei of the heaviest elements, thereby probing nuclear structure models near the ‘Island of Stability’ with unprecedented experimental precision.
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| 39. |
- Rudolph, Dirk, et al.
(författare)
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Spectroscopy of Element 115 Decay Chains
- 2013
-
Ingår i: Physical Review Letters. - 1079-7114. ; 111:11
-
Tidskriftsartikel (refereegranskat)abstract
- A high-resolution , X-ray and gamma-ray coincidence spectroscopy experiment was conducted at the GSI Helmholtzzentrum für Schwerionenforschung. Thirty correlated alpha-decay chains were detected following the fusion-evaporation reaction 48Ca + 243Am. The observations are consistent with previous assignments of similar decay chains to originate from element Z = 115. For the first time, precise spectroscopy allows the derivation of excitation schemes of isotopes along the decay chains starting with elements Z > 112. Comprehensive Monte-Carlo simulations accompany the data analysis. Nuclear structure models provide a first level interpretation.
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| 40. |
- Rudolph, Dirk, et al.
(författare)
-
Superheavy-element spectroscopy: Correlations along element 115 decay chains
- 2016
-
Ingår i: 12th International Conference on Nucleus-Nucleus Collisions (NN 2015) : EPJ Web of Conferences - EPJ Web of Conferences. - : EDP Sciences. - 9788874381012 ; 117, s. 1-12
-
Konferensbidrag (refereegranskat)abstract
- Following a brief summary of the region of the heaviest atomic nuclei yet created in the laboratory, data on more than hundred α-decay chains associated with the production of element 115 are combined to investigate time and energy correlations along the observed decay chains. Several of these are analysed using a new method for statistical assessments of lifetimes in sets of decay chains.
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| 41. |
- Sarmiento, Luis, et al.
(författare)
-
Comparing net zero pathways across the Atlantic A model inter-comparison exercise between the Energy Modeling Forum 37 and the European Climate and Energy Modeling Forum
- 2024
-
Ingår i: Energy and Climate Change. - : Elsevier BV. - 2666-2787. ; 5
-
Tidskriftsartikel (refereegranskat)abstract
- Europe and North America account for 32 % of current carbon emissions. Due to distinct legacy systems, energy infrastructure, socioeconomic development, and energy resource endowment, both regions have different policy and technological pathways to reach net zero by the mid-century. Against this background, our paper examines the results from the net zero emission scenarios for Europe and North America that emerged from the collaboration of the European and American Energy Modeling Forums. In our analysis, we perform an inter-comparison of various integrated assessments and bottom-up energy system models. A clear qualitative consensus emerges on five main points. First, Europe and the United States reach net zero targets with electrification, demand-side reductions, and carbon capture and sequestration technologies. Second, the use of carbon capture and sequestration is more predominant in the United States due to a steeper decarbonization schedule. Third, the buildings sector is the easiest to electrify in both regions. Fourth, the industrial sector is the hardest to electrify in the United States and transportation in Europe. Fifth, in both regions, the transition in the energy mix is driven by the substitution of coal and natural gas with solar and wind, but to a different extent.
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| 42. |
- Sarmiento, Luis, et al.
(författare)
-
Copy number of the X-linked genes TLR7 and CD40L influences innate and adaptive immune responses
- 2019
-
Ingår i: Scandinavian Journal of Immunology. - : Wiley. - 0300-9475 .- 1365-3083. ; 90:2
-
Tidskriftsartikel (refereegranskat)abstract
- The number of the X chromosome–linked genes has been previously suggested to influence immune responses and the development of autoimmune diseases. In the present study, we aimed at evaluating the level of expression of CD40L (an X-linked gene involved in adaptive immunity) and TLR7 (an X-linked gene involved in innate immunity) in a variety of different karyotypes. Those included males, females and patients with X chromosome aneuploidy. Healthy females (46, XX; n = 10) and healthy males (46, XY; n = 10) were compared to females with Turner syndrome (TS) (45, X; n = 11) and males with Klinefelter syndrome (KS) (47, XXY; n = 5). Stimulation of peripheral blood mononuclear cells (PBMCs) with PMA and ionomycin resulted in higher percentage of CD3 + CD40L+ T cells (P < 0.001) and higher level expression of CD40L in T cell (P < 0.001) in female and KS patients compared with male and TS patients. TLR7-mediated IFN-alpha production by HLADR + CD3− CD19− cells was significantly upregulated in healthy women compared with healthy males, TS and KS patients (P < 0.001). TLR7 agonist-stimulated PBMCs from healthy females and KS patients expressed significantly higher levels of TLR7 mRNA than those from male and TS patients (P < 0.05). The increased expression of the X-linked genes TLR7 and CD40L in healthy females and KS patients suggests that the presence of two X chromosomes plays a major role in enhancing both innate and adaptive immune responses. These results may contribute to the explanation of sex-based differences in immune biology and the sex bias in predisposition to autoimmune diseases.
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| 43. |
- Sarmiento, Luis, et al.
(författare)
-
Field strains of Echovirus 6 infect human endocrine and exocrine pancreatic cells and induce pro-inflammatory innate immune responses.
-
Tidskriftsartikel (refereegranskat)abstract
- Increasing evidence suggests that type 1 diabetes (T1D) is a combined endocrine-exocrine disease. Human enteroviruses (HEV) have been suggested to induce T1D, but so far evidence on HEV infection in human pancreas has been reported only in islets and ductal cells. Aim of this study was to investigate the capability of HEV strains to infect primary human endocrine and exocrine pancreatic cells and to induce the expression of innate immunity genes in both cell types. Isolated human pancreatic islets and exocrine cells were either mock-infected or inoculated with seven field isolates of Echovirus 6 (E6). Beta-cell tropic strains of E4, E16 and E30 were assayed in primary exocrine cells. Viral infection, replication, virus-induced cytopathic effect (CPE) and expression of innate immunity genes were measured. All the seven strains of E6 replicated in both pancreatic endocrine and exocrine cells with infectious progeny production and appearance of CPE. By contrast, no virus titer increase or CPE were observed in exocrine cells exposed to E4, E16 and E30. Virus particles were found in E6-infected acinar cells, both free in cytoplasm and enclosed in vacuoles. Insulin granules accumulation in proximity to virus particles and beta cells functional impairment were demonstrated in E6-infected islets. Endocrine and exocrine cells responded to E6 infection by upregulating the transcription of genes involved in viral recognition (IF1H1), antiviral defense (OAS1, IFN-β) and inflammation (CXCL10, CCL5). Our results indicate that islets and exocrine pancreatic cells productively support the E6 infection and suggest that HEV-associated T1D may involve both endocrine and exocrine pancreas.
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| 44. |
- Sarmiento, Luis G.
(författare)
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Nuclear spectroscopy with GEANT4 : The superheavy challenge
- 2016
-
Ingår i: Nobel Symposium NS 160 - Chemistry and Physics of Heavy and Superheavy Elements. - : EDP Sciences. - 9782759890118 ; 131
-
Konferensbidrag (refereegranskat)abstract
- The simulation toolkit Geant4 was originally developed at CERN for high-energy physics. Over the years it has been established as a swiss army knife not only in particle physics but it has seen an accelerated expansion towards nuclear physics and more recently to medical imaging and y- and ion-therapy to mention but a handful of new applications. The validity of Geant4 is vast and large across many particles, ions, materials, and physical processes with typically various different models to choose from. Unfortunately, atomic nuclei with atomic number Z > 100 are not properly supported. This is likely due to the rather novelty of the field, its comparably small user base, and scarce evaluated experimental data. To circumvent this situation different workarounds have been used over the years. In this work the simulation toolkit Geant4 will be introduced with its different components and the effort to bring the software to the heavy and superheavy region will be described.
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| 45. |
- Sarmiento, Luis, et al.
(författare)
-
GEANT4 Spectroscopy of Heavy and Superheavy Atomic Nuclei: Element 115
- 2013
-
Ingår i: Proceedings of Science. - 1824-8039. ; 194
-
Tidskriftsartikel (refereegranskat)abstract
- A high-resolution alpha, electron, X-ray and gamma-ray coincidence experiment was conducted at the GSI Helmholtzzentrum für Schwerionenforschung GmbH in Darmstadt, Germany. It aimed to identify and study alpha-decay chains of isotopes of element Z=115. Experimental data, including the 30 identified chains, were analyzed self-consistently with a virtually constructed spectroscopic set-up using GEANT4. A workaround which allows for the use of this simulation toolkit for elements Z>100 is presented. The interpretation of the real experimental data, i.e. the derived decay schemes of some of heaviest man-made atomic nuclei, crucially depends on the cross check with the virtual “GEANT4 spectroscopy” experiment.
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| 46. |
- Sarmiento, Luis, et al.
(författare)
-
Nuclear spectroscopy with Geant4: Proton and neutron emission & radioactivity
- 2016
-
Ingår i: Latin American Symposium on Nuclear Physics and Applications. - : Author(s). - 9780735414112 ; 1753
-
Konferensbidrag (refereegranskat)abstract
- With the aid of a novel combination of existing equipment – JYFLTRAP and the TASISpec decay station – it is possible to perform very clean quantum-state selective, high-resolution particle-γ decay spectroscopy. We intend to study the determination of the branching ratio of the ℓ = 9 proton emission from the Iπ = 19/2−, 3174-keV isomer in the N = Z − 1 nucleus 53Co. The study aims to initiate a series of similar experiments along the proton dripline, thereby providing unique insights into “open quantum systems”. The technique has been pioneered in case studies using SHIPTRAP and TASISpec at GSI. Newly available radioactive decay modes in Geant4 simulations are going to corroborate the anticipated experimental results.
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| 47. |
- Sarmiento, Luis, et al.
(författare)
-
Type 1 diabetes associated and tissue transglutaminase autoantibodies in patients without type 1 diabetes and coeliac disease with confirmed viral infections
- 2012
-
Ingår i: Journal of Medical Virology. - : Wiley. - 1096-9071 .- 0146-6615. ; 84:7, s. 1049-1053
-
Tidskriftsartikel (refereegranskat)abstract
- Coeliac disease and type 1 diabetes are autoimmune diseases that may share the same initiating environmental factors. In this study, the occurrence of type 1 diabetes associated autoantibodies (GADA and IA-2A) and tissue transglutaminase autoantibodies (TGA) was determined in patients with confirmed viral infections and no signs of type 1 diabetes or coeliac disease. Serum samples from 82 Cuban patients tested positive for PCR and IgG specific to enterovirus (HEV, serotype echovirus 16, 20 samples), EpsteinBarr virus (EBV, 20 samples), cytomegalovirus (CMV, 21 samples), and hepatitis C virus (HCV, 21 samples); and sera from 164 controls negative serologically to EBV, CMV, HCV, and echovirus 16 were enrolled in the study. All subjects were screened for GADA, IA-2A, and TGA. The prevalence of TGA in patients infected with HEV, EBV, CMV, or HCV was 55% (11/20), 25% (5/20), 9.5% (2/21), and 9.5% (2/21), respectively. GADA and IA-2A were found in 15% (3/20) and 25% (5/20) of patients infected with HEV. None of the patients infected by EBV, CMV, and HCV had GADA or IA-2A. All children infected with HEV who were positive for type 1 diabetes-associated autoantibodies were also TGA-positive. None of the sera from uninfected subjects were positive for GADA, IA-2A or TGA. In conclusion, TGA can develop during infection with HEV, EBV, CMV, or HCV, while the emergence of islet cell related autoantibodies is restricted to HEV infections. The findings suggest that HEV may be a shared environmental factor for the development of islet and gut-related autoimmunity. J. Med. Virol. 84: 10491053, 2012. (C) 2012 Wiley Periodicals, Inc.
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| 48. |
- Sarmiento-Pérez, Luis, et al.
(författare)
-
Differential effects of three echovirus strains on cell lysis and insulin secretion in beta cell derived lines
- 2016
-
Ingår i: Journal of Medical Virology. - : Wiley. - 0146-6615 .- 1096-9071. ; 88:6, s. 971-978
-
Tidskriftsartikel (refereegranskat)abstract
- In an earlier study, infection of human pancreatic islets with epidemic strains of echovirus (E4, E16, E30), with proven but differently ability to induce islet autoimmunity, resulted either in a severe damage (i.e., E16 and E30) or proceeded without visible changes in infected islets (i.e., E4). In this study, the ability of these strains to replicate in beta cells and the consequence of such an infection for beta cell lysis and beta cell function was studied in the pancreatic beta cell lines INS-1, MIN6, and NIT-1. The strains of E16 and E30 did replicate in INS1, MIN6, and NIT1 cells and resulted in a pronounced cytopathic effect within 3 days following infection. By contrast, E4 replicated in all examined insulinoma cells with no apparent cell destruction. The insulin release in response to high glucose stimulation was hampered in all infected cells (P<0.05) when no evidence of cytolysis was present; however, the adverse effect of E16 and E30 on insulin secretion appeared to be higher than that of the E4 strain. The differential effects of echovirus infection on cell lysis, and beta cell function in the rodent insulinoma INS1, MIN6, and NIT 1 cells reflect those previously obtained in primary human islets and support the notion that the insulinproducing beta cells can harbor a non-cytopathic viral infection.
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| 49. |
- Sarmiento-Pérez, Luis, et al.
(författare)
-
Echovirus 6 infects human exocrine and endocrine pancreatic cells and induces pro-inflammatory innate immune response
- 2017
-
Ingår i: Viruses. - : MDPI AG. - 1999-4915. ; 9:2
-
Tidskriftsartikel (refereegranskat)abstract
- Human enteroviruses (HEV), especially coxsackievirus serotype B (CVB) and echovirus (E), have been associated with diseases of both the exocrine and endocrine pancreas, but so far evidence on HEV infection in human pancreas has been reported only in islets and ductal cells. This study aimed to investigate the capability of echovirus strains to infect human exocrine and endocrine pancreatic cells. Infection of explanted human islets and exocrine cells with seven field strains of E6 caused cytopathic effect, virus titer increase and production of HEV protein VP1 in both cell types. Virus particles were found in islets and acinar cells infected with E6. No cytopathic effect or infectious progeny production was observed in exocrine cells exposed to the beta cell-tropic strains of E16 and E30. Endocrine cells responded to E6, E16 and E30 by upregulating the transcription of interferon-induced with helicase C domain 1 (IF1H1), 2ʹ-5ʹ-oligoadenylate synthetase 1 (OAS1), interferon-β (IFN-β), chemokine (C-X-C motif) ligand 10 (CXCL10) and chemokine (C-C motif) ligand 5 (CCL5). Echovirus 6, but not E16 or E30, led to increased transcription of these genes in exocrine cells. These data demonstrate for the first time that human exocrine cells represent a target for E6 infection and suggest that certain HEV serotypes can replicate in human pancreatic exocrine cells, while the pancreatic endocrine cells are permissive to a wider range of HEV.
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| 50. |
- Sarmiento-Pérez, Luis, et al.
(författare)
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Expression of Innate Immunity Genes and Damage of Primary Human Pancreatic Islets by Epidemic Strains of Echovirus : Implication for Post-Virus Islet Autoimmunity
- 2013
-
Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 8:11, s. e77850-
-
Tidskriftsartikel (refereegranskat)abstract
- Three large-scale Echovirus (E) epidemics (E4, E16, E30), each differently associated to the acute development of diabetes related autoantibodies, have been documented in Cuba. The prevalence of islet cell autoantibodies was moderate during the E4 epidemic but high in the E16 and E30 epidemic. The aim of this study was to evaluate the effect of epidemic strains of echovirus on beta-cell lysis, beta-cell function and innate immunity gene expression in primary human pancreatic islets. Human islets from non-diabetic donors (n = 7) were infected with the virus strains E4, E16 and E30, all isolated from patients with aseptic meningitis who seroconverted to islet cell antibody positivity. Viral replication, degree of cytolysis, insulin release in response to high glucose as well as mRNA expression of innate immunity genes (IFN-b, RANTES, RIG-I, MDA5, TLR3 and OAS) were measured. The strains of E16 and E30 did replicate well in all islets examined, resulting in marked cytotoxic effects. E4 did not cause any effects on cell lysis, however it was able to replicate in 2 out of 7 islet donors. Beta-cell function was hampered in all infected islets (P<0.05); however the effect of E16 and E30 on insulin secretion appeared to be higher than the strain of E4. TLR3 and IFN-beta mRNA expression increased significantly following infection with E16 and E30 (P<0.033 and P<0.039 respectively). In contrast, the expression of none of the innate immunity genes studied was altered in E4-infected islets. These findings suggest that the extent of the epidemic-associated islet autoimmunity may depend on the ability of the viral strains to damage islet cells and induce pro-inflammatory innate immune responses within the infected islets.
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