| 1. |
- Hultberg, Tove, et al.
(författare)
-
The late-Holocene decline of Tilia in relation to climate and human activities - pollen evidence from 42 sites in southern Sweden
- 2017
-
Ingår i: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 44:10, s. 2398-2409
-
Tidskriftsartikel (refereegranskat)abstract
- Aim: The dominant role of Tilia in primeval forests of Scandinavia has long been recognized, but the timing and mechanisms for its decline have not been completely unravelled. A particular uncertainty involves the balance between climate and human activities as the drivers of the change. One reason for the uncertainty is the challenge in evaluating the past cover of the genus owing to its poorly dispersed pollen; another is that a multi-site study would be required to trace subregional differences. To overcome these obstacles, we here apply two different analytical methods to pollen data from 42 sites in two distinct vegetation zones of Sweden. Location: Temperate and hemi-boreal vegetation zones of southern Sweden. Methods: Generalized additive mixed models (GAMM) were used to model the development of Tilia and cereal pollen percentages over time. Twelve sites were used for reconstruction of local cover of Tilia using the landscape reconstruction algorithm (LRA). Results: Before 4000 cal. bp the Tilia mean pollen percentages were similar in the two vegetation zones. Thereafter, values in the hemi-boreal zone declined, with less Tilia since around 3000 cal. bp. In contrast, Tilia did not decrease in the temperate zone until this past millennium. The LRA application revealed that in some forests a large cover of Tilia remained considerably longer than has traditionally been estimated by pollen percentages alone. Main conclusions: By using a large coherent dataset we found significant differences in how the abundance and distribution of Tilia changed through time between two adjacent vegetation zones. We interpret the initial decline in the northern hemi-boreal zone to be driven by cooling climate, and the later decline in the southern temperate zone to be driven more by human land-use.
|
|
| 2. |
- Reepalu, Anton, et al.
(författare)
-
Development of an algorithm for determination of the likelihood of virological failure in HIV-positive adults receiving antiretroviral therapy in decentralized care
- 2017
-
Ingår i: Global Health Action. - : Informa UK Limited. - 1654-9716 .- 1654-9880. ; 10:1
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Early identification of virological failure (VF) limits occurrence and spread of drug-resistant viruses in patients receiving antiretroviral treatment (ART). Viral load (VL) monitoring is therefore recommended, but capacities to comply with this are insufficient in many low-income countries. Clinical algorithms might identify persons at higher likelihood of VF to allocate VL resources. Objectives: We aimed to construct a VF algorithm (the Viral Load Testing Criteria; VLTC) and compare its performance to the 2013 WHO treatment failure criteria. Methods: Subjects with VL results available 1 year after ART start (n = 494) were identified from a cohort of ART-naïve adults (n = 812), prospectively recruited and followed 2011-2015 at Ethiopian health centres. VF was defined as VL≥1000 copies/mL. Variables recorded at the time of sampling, with potential association with VF, were used to construct the algorithm based on multivariate logistic regression. Results: Fifty-seven individuals (12%) had VF, which was independently associated with CD4 count <350 cells/mm3, previous ART interruption, and short mid-upper arm circumference (<24cm and <23cm, for men and women, respectively). These variables were included in the VLTC. In derivation, the VLTC identified 52/57 with VF; sensitivity 91%, specificity 43%, positive predictive value (PPV) 17%, negative predictive value (NPV) 97%. In comparison, the WHO criteria identified 38/57 with VF (sensitivity 67%, specificity 74%, PPV 25%, NPV 94%). Conclusions: The VLTC identified subjects at greater likelihood of VF, with higher sensitivity and NPV than the WHO criteria. If external validation confirms this performance, these criteria could be used to allocate limited VL resources. Due to its limited specificity, it cannot be used to determine treatment failure in the absence of a confirmatory viral load.
|
|
| 3. |
- Alaridah, Nader, et al.
(författare)
-
Impaired CXCR1-dependent oxidative defence in active tuberculosis patients.
- 2015
-
Ingår i: Tuberculosis. - : Elsevier BV. - 1873-281X .- 1472-9792. ; 95:6, s. 744-750
-
Tidskriftsartikel (refereegranskat)abstract
- Much of the pronounced host inflammatory response that occurs in tuberculosis (TB) is related to failed immunity against the invading pathogen. The G-protein coupled receptors CXCR1 and CXCR2 are implicated in important signal transduction pathways in lung inflammatory responses. We investigated the expression and function of these receptors in a simple whole blood model from 24 patients with pulmonary TB and in subjects with latent TB infection (LTBI). Healthy controls were recruited from close contacts to the pulmonary index patients. We found that pulmonary TB patients had significantly increased CXCR1 expression on blood cells compared to LTBI subjects and controls (p < 0.001). In contrast, LTBI subjects had a significant increase in CXCR2 expression compared to pulmonary TB patients (p < 0.001) and controls (p < 0.01). Leukocyte function, measured as oxidative capacity, was decreased in pulmonary TB patients compared to LTBI and controls (p < 0.001) and correlated with the increased CXCR1 expression. Leukocyte recruitment, measured as the expression of microRNA-223 was increased in pulmonary TB patients compared to LTBI (p < 0.05). We found that variations in receptor expression are linked to disease progression and affect the immune response against Mycobacterium tuberculosis (Mtb).
|
|
| 4. |
- Arimide, Dawit Assefa, et al.
(författare)
-
HIV-genetic diversity and drug resistance transmission clusters in Gondar, Northern Ethiopia, 2003-2013
- 2018
-
Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 13:10
-
Tidskriftsartikel (refereegranskat)abstract
- Background The HIV-1 epidemic in Ethiopia has been shown to be dominated by two phylogenetically distinct subtype C clades, the Ethiopian (C'-ET) and East African (C-EA) clades, however, little is known about the temporal dynamics of the HIV epidemic with respect to subtypes and distinct clades. Moreover, there is only limited information concerning transmission of HIV-1 drug resistance (TDR) in the country. Methods A cross-sectional survey was conducted among young antiretroviral therapy (ART)-naïve individuals recently diagnosed with HIV infection, in Gondar, Ethiopia, 2011-2013 using the WHO recommended threshold survey. A total of 84 study participants with a median age of 22 years were enrolled. HIV-1 genotyping was performed and investigated for drug resistance in 67 individuals. Phylogenetic analyses were performed on all available HIV sequences obtained from Gondar (n = 301) which were used to define subtype C clades, temporal trends and local transmission clusters. Dating of transmission clusters was performed using BEAST. Result Four of 67 individuals (6.0%) carried a HIV drug resistance mutation strain, all associated with non-nucleoside reverse transcriptase inhibitors (NNRTI). Strains of the C-EA clade were most prevalent as we found no evidence of temporal changes during this time period. However, strains of the C-SA clade, prevalent in Southern Africa, have been introduced in Ethiopia, and became more abundant during the study period. The oldest Gondar transmission clusters dated back to 1980 (C-EA), 1983 (C-SA) and 1990 (C'-ET) indicating the presence of strains of different subtype C clades at about the same time point in Gondar. Moreover, some of the larger clusters dated back to the 1980s but transmissions within clusters have been ongoing up till end of the study period. Besides being associated with more sequences and larger clusters, the C-EA clade sequences were also associated with clustering of HIVDR sequences. One cluster was associated with the G190A mutation and showed onward transmissions at high rate. Conclusion TDR was detected in 6.0% of the sequenced samples and confirmed pervious reports that the two subtype C clades, C-EA and C'-ET, are common in Ethiopia. Moreover, the findings indicated an increased diversity in the epidemic as well as differences in transmission clusters sizes of the different clades and association with resistance mutations. These findings provide epidemiological insights not directly available using standard surveillance and may inform the adjustment of public health strategies in HIV prevention in Ethiopia.
|
|
| 5. |
|
|
| 6. |
- Björk, Yvonne, et al.
(författare)
-
Androgens in women after allogeneic hematopoietic cell transplantation : Impact of chronic GvHD and glucocorticoid therapy
- 2017
-
Ingår i: Bone Marrow Transplantation. - : Springer Science and Business Media LLC. - 0268-3369 .- 1476-5365. ; 52:3, s. 431-437
-
Tidskriftsartikel (refereegranskat)abstract
- Low androgen levels may contribute to sexual dysfunction in women after allogeneic hematopoietic cell transplantation (alloHCT). However, data on serum androgens in women after alloHCT are limited. The aim of this study was to assess androgen levels and their association with chronic GvHD (cGvHD) and glucocorticoid (GC) therapy. Included were 65 allografted women, 33 with cGvHD, and 23 of these were on GC therapy. Controls were 94 healthy, age-matched women. Supportive study groups were women after autologous HCT (autoHCT; n=20) and non-transplanted women on GC therapy (n=26). Compared with controls, free testosterone (free T) and dehydroepiandrosterone sulfate (DHEAS) levels were lower in both the alloHCT group and GC groups; P<0.0001 and P<0.05, respectively. Androgens in the autoHCT group were similar or higher than controls. In the subgroup of alloHCT patients without cGvHD, free T was similar to controls (7.2 vs 8.6 pmol/L; P=0.42), whereas DHEAS levels was lower than controls (1.7 vs 2.5 μmol/L; P=0.008). Compared with controls, cGvHD without GC (n=10) was associated with lower free T and DHEAS; P=0.004 and P=0.0004, respectively). The lowest androgen levels were seen in women with both cGvHD and GC therapy. In conclusion, low serum androgens were associated with cGvHD and GC therapy, prompting for studies assessing a possible association between low androgens and sexual dysfunction and quality of life in allografted women.
|
|
| 7. |
- Björkman, Andrea, et al.
(författare)
-
Aberrant recombination and repair during immunoglobulin class switching in BRCA1-deficient human B cells.
- 2015
-
Ingår i: Proceedings of the National Academy of Sciences. - : Proceedings of the National Academy of Sciences. - 1091-6490 .- 0027-8424. ; 112:7, s. 2157-2162
-
Tidskriftsartikel (refereegranskat)abstract
- Breast cancer type 1 susceptibility protein (BRCA1) has a multitude of functions that contribute to genome integrity and tumor suppression. Its participation in the repair of DNA double-strand breaks (DSBs) during homologous recombination (HR) is well recognized, whereas its involvement in the second major DSB repair pathway, nonhomologous end-joining (NHEJ), remains controversial. Here we have studied the role of BRCA1 in the repair of DSBs in switch (S) regions during immunoglobulin class switch recombination, a physiological, deletion/recombination process that relies on the classical NHEJ machinery. A shift to the use of microhomology-based, alternative end-joining (A-EJ) and increased frequencies of intra-S region deletions as well as insertions of inverted S sequences were observed at the recombination junctions amplified from BRCA1-deficient human B cells. Furthermore, increased use of long microhomologies was found at recombination junctions derived from E3 ubiquitin-protein ligase RNF168-deficient, Fanconi anemia group J protein (FACJ, BRIP1)-deficient, or DNA endonuclease RBBP8 (CtIP)-compromised cells, whereas an increased frequency of S-region inversions was observed in breast cancer type 2 susceptibility protein (BRCA2)-deficient cells. Thus, BRCA1, together with its interaction partners, seems to play an important role in repairing DSBs generated during class switch recombination by promoting the classical NHEJ pathway. This may not only provide a general mechanism underlying BRCA1's function in maintaining genome stability and tumor suppression but may also point to a previously unrecognized role of BRCA1 in B-cell lymphomagenesis.
|
|
| 8. |
- Dahlman, Disa, et al.
(författare)
-
Both localized and systemic bacterial infections are predicted by injection drug use : A prospective follow-up study in Swedish criminal justice clients
- 2018
-
Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 13:5
-
Tidskriftsartikel (refereegranskat)abstract
- Background Both skin and soft tissue infections (SSTI) and systemic bacterial infections are common in people who inject drugs (PWID), but data on incidence and risk factors are lacking. We compared registered diagnoses for such infections in Swedish criminal justice clients with regard to injecting drug use. Methods Baseline interview data from the Swedish Prison and Probation Service on drug use in PWID and non-PWID with problematic alcohol use were linked to follow-up data from national Swedish registers on hospital diagnoses and/or death. Associations between drug use and later diagnosis of SSTI and systemic bacterial infection (septicemia or bacterial infection of the heart, bone/joints or central nervous system) were analyzed by Cox regression. Results Incidence rates of SSTI was 28.3 per 1,000 person-years for PWID (n = 2,444) and 10.0 for non-PWID with problematic alcohol use (n = 735). Incidence rates of systemic bacterial infection was 9.1 per 1,000 person-years for PWID and 2.7 per 1,000 person-years for non-PWID. Injection drug use was associated with a significantly increased risk of bacterial infections, for main drugs heroin (SSTI: Hazard ratio [HR] 2.45; systemic infection: HR 2.75), amphetamine (SSTI: HR 1.60; systemic infection: HR 2.19), and polysubstance use (SSTI: HR 1.92; systemic infection: HR 2.01). In relation to injection use of amphetamine and polysubstance use, PWID mainly using heroin had higher risk of SSTI. Conclusions Injection drug use predicted both SSTI and systemic bacterial infection, with a particularly high risk of SSTI in PWID mainly using heroin. The results imply the need for increased attention to bacterial infections among PWID, in terms of clinical management, prevention and research.
|
|
| 9. |
|
|
| 10. |
- Dahlman, Disa, et al.
(författare)
-
Opioid and amphetamine dependence is associated with methicillin-resistant Staphylococcus aureus (MRSA) : An epidemiological register study with 73,201 Swedish in- and outpatients 1997–2013
- 2017
-
Ingår i: Infectious Diseases. - : Informa UK Limited. - 2374-4243 .- 2374-4235. ; 49:2, s. 120-127
-
Tidskriftsartikel (refereegranskat)abstract
- Background: While methicillin-resistant Staphylococcus aureus (MRSA) is increasing in prevalence globally, Sweden is still a low-prevalence country enabling studies on the natural MRSA spread in subpopulations unaffected by a surrounding highly infected population. Substance dependence and injection drug use have been risk factors for MRSA carriage and infection in other countries. In this retrospective, longitudinal register study, we investigated MRSA epidemiology 1997–2013 in opioid and amphetamine-dependent individuals, in comparison with alcohol-dependent subjects. Methods: Data from the national Swedish in- and outpatients registers included 73,201 individuals from 1997, 1999, 2004, 2009 and 2013. We analyzed substance use disorder and demographic predictors for MRSA using generalized estimating equations. Results: The main finding was that both opioid (adjusted odds ratio [AOR] = 2.82; 95% confidence interval [CI] = 2.16, 3.67) and amphetamine dependence (AOR = 2.71; 95% CI = 1.70, 4.16) were significantly associated with MRSA diagnosis compared with alcohol dependence, when adjusting for age, sex and year. Conclusions: These findings are of value to understand the dynamics of MRSA epidemiology among substance dependent persons with presumably low socioeconomic status and potential injection drug use, and implicate repeated surveillance of MRSA among these patients.
|
|
