| 1. |
- Alalam, Hanna, et al.
(author)
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A High-Throughput Method for Screening for Genes Controlling Bacterial Conjugation of Antibiotic Resistance.
- 2020
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In: mSystems. - 2379-5077. ; 5:6
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Journal article (peer-reviewed)abstract
- The rapid horizontal transmission of antibiotic resistance genes on conjugative plasmids between bacterial host cells is a major cause of the accelerating antibiotic resistance crisis. There are currently no experimental platforms for fast and cost-efficient screening of genetic effects on antibiotic resistance transmission by conjugation, which prevents understanding and targeting conjugation. We introduce a novel experimental framework to screen for conjugation-based horizontal transmission of antibiotic resistance between >60,000 pairs of cell populations in parallel. Plasmid-carrying donor strains are constructed in high-throughput. We then mix the resistance plasmid-carrying donors with recipients in a design where only transconjugants can reproduce, measure growth in dense intervals, and extract transmission times as the growth lag. As proof-of-principle, we exhaustively explore chromosomal genes controlling F-plasmid donation within Escherichia coli populations, by screening the Keio deletion collection in high replication. We recover all seven known chromosomal gene mutants affecting conjugation as donors and identify many novel mutants, all of which diminish antibiotic resistance transmission. We validate nine of the novel genes' effects in liquid mating assays and complement one of the novel genes' effect on conjugation (rseA). The new framework holds great potential for exhaustive disclosing of candidate targets for helper drugs that delay resistance development in patients and societies and improve the longevity of current and future antibiotics. Further, the platform can easily be adapted to explore interspecies conjugation, plasmid-borne factors, and experimental evolution and be used for rapid construction of strains.IMPORTANCE The rapid transmission of antibiotic resistance genes on conjugative plasmids between bacterial host cells is a major cause of the accelerating antibiotic resistance crisis. There are currently no experimental platforms for fast and cost-efficient screening of genetic effects on antibiotic resistance transmission by conjugation, which prevents understanding and targeting conjugation. We introduce a novel experimental framework to screen for conjugation-based horizontal transmission of antibiotic resistance between >60,000 pairs of cell populations in parallel. As proof-of-principle, we exhaustively explore chromosomal genes controlling F-plasmid donation within E. coli populations. We recover all previously known and many novel chromosomal gene mutants that affect conjugation efficiency. The new framework holds great potential for rapid screening of compounds that decrease transmission. Further, the platform can easily be adapted to explore interspecies conjugation, plasmid-borne factors, and experimental evolution and be used for rapid construction of strains.
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| 2. |
- Alalam, Hanna, et al.
(author)
-
Conjugation factors controlling F-plasmid antibiotic resistance transmission
- 2018
-
In: BioRxiv. - : Cold Spring Harbor Laboratory.
-
Journal article (other academic/artistic)abstract
- The rapid horizontal transmission of many antibiotic resistance genes between bacterial host cells on conjugative plasmids is a major cause of the accelerating antibiotic resistance crisis. Preventing understanding and targeting conjugation, there currently are no experimental platforms for fast and cost-efficient screening of genetic effects on antibiotic resistance transmission by conjugation. We introduce a novel experimental framework to screen for conjugation based horizontal transmission of antibiotic resistance between >60,000 pairs of cell populations in parallel. Plasmid-carrying donor strains are constructed in high throughput. We then mix the resistance plasmid carrying donors with recipients in a design where only transconjugants can reproduce, measure growth in dense intervals and extract transmission times as the growth lag. As proof-of-principle, we exhaustively explored chromosomal genes controlling F plasmid donation within E. coli populations, by screening the Keio deletion collection at high replication. We recover all six known chromosomal gene mutants affecting conjugation and identify >50 novel factors, all of which diminish antibiotic resistance transmission. We verify 10 of the novel genes' effects in a liquid mating assay. The new framework holds great potential for exhaustive disclosing of candidate targets for helper drugs that delay resistance development in patients and societies and improves the longevity of current and future antibiotics.
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| 3. |
- Bäckberg, Matilda, et al.
(author)
-
Using in vitro receptor activity studies of synthetic cannabinoids to support the risk assessment of new psychoactive substances – A Swedish strategy to protect public health from harm
- 2023
-
In: Forensic Science International. - : Elsevier Ireland Ltd. - 0379-0738 .- 1872-6283. ; 348
-
Journal article (peer-reviewed)abstract
- In the past 15 years, close to 1000 of new psychoactive substances (NPS) have been reported in Europe and globally. At the time of identification, data on safety, toxicity and carcinogenic potential of many NPS are not available or very limited. To work more efficiently, a strategy and collaboration between the Public Health Agency of Sweden (PHAS) and the National Board of Forensic Medicine was established involving in vitro receptor activity assays to demonstrate neurological activity of NPS. This report summarizes the first results on the synthetic cannabinoid receptor agonists (SCRAs), and subsequent actions taken by PHAS. A total of 18 potential SCRAs were selected by PHAS for in vitro pharmacological characterization. 17 compounds could be acquired and investigated for their activity on the human cannabinoid-1 (CB1) receptors expressed together with the AequoScreen system in CHO-K1 cells. Dose-response curves were established using eight different concentrations in triplicates at three occasions with JWH-018 as reference. For the MDMB-4en-PINACA, MMB-022, ACHMINACA, ADB-BUTINACA, 5F-CUMYL-PeGACLONE, 5C-AKB48, NM-2201, 5F-CUMYL-PINACA, JWH-022, 5Cl-AB-PINACA, MPhP-2201, 5F-AKB57 the half maximal effective concentration values ranged from 2.2 nM (5F-CUMYL-PINACA) to 171 nM (MMB-022). EG-018 and 3,5-AB-CHMFUPPYCA were none-active. The results contributed to 14 of these compounds being scheduled as narcotics in Sweden. In conclusion, many of the emerging SCRAs are potent activators of the CB1 receptor in vitro, although some lack activity or are partial agonists. The new strategy proved useful when data on psychoactive effects of the SCRAs under investigation were not available or limited. © 2023 The Authors
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| 4. |
- Cloetens, Lieselotte, et al.
(author)
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Role of dietary beta-glucans in the prevention of the metabolic syndrome.
- 2012
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In: Nutrition Reviews. - : Oxford University Press (OUP). - 1753-4887 .- 0029-6643. ; 70:8, s. 444-458
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Journal article (peer-reviewed)abstract
- The present review examines the evidence regarding the effect of β-glucan on variables linked to the metabolic syndrome (MetS), including appetite control, glucose control, hypertension, and gut microbiota composition. Appetite control can indirectly influence MetS by inducing a decreased energy intake, and promising results for a β-glucan intake to decrease appetite have been found using gut hormone responses and subjective appetite indicators. Beta-glucan also improves the glycemic index of meals and beneficially influences glucose metabolism in patients with type 2 diabetes or MetS, as well as in healthy subjects. Furthermore, a blood-pressure-lowering effect of β-glucan in hypertensive subjects seems fairly well substantiated. The gut microbiota composition might be an interesting target to prevent MetS, and preliminary results indicate the prebiotic potential of β-glucan. The evidence that β-glucan influences appetite control and gut microbiota in a positive way is still insufficient or difficult to interpret, and additional studies are needed in this field. Still, much evidence indicates that increased β-glucan intake could prevent MetS. Such evidence should encourage increased efforts toward the development of β-glucan-containing functional foods and promote the intake of β-glucan-rich foods, with the aim of reducing healthcare costs and disease prevalence.
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| 5. |
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| 6. |
- Folkenant, Matilda, et al.
(author)
-
Structure and properties of Cr–C/Ag films deposited by magnetron sputtering
- 2015
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In: Surface & Coatings Technology. - : Elsevier. - 0257-8972 .- 1879-3347. ; 281, s. 184-192
-
Journal article (peer-reviewed)abstract
- Cr–C/Ag thin films with 0–14 at.% Ag have been deposited by magnetron sputtering from elemental targets. The samples were analyzed by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) to study their structure and chemical bonding. A complex nanocomposite structure consisting of three phases; nanocrystalline Ag, amorphous CrCx and amorphous carbon is reported. The carbon content in the amorphous carbide phase was determined to be 32–33 at.% C, independent of Ag content. Furthermore, SEM and XPS results showed higher amounts of Ag on the surface compared to the bulk. The hardness and Young's modulus were reduced from 12 to 8 GPa and from 270 to 170 GPa, respectively, with increasing Ag content. The contact resistance was found to decrease with Ag addition, with the most Ag rich sample approaching the values of an Ag reference sample. Initial tribological tests gave friction coefficients in the range of 0.3 to 0.5, with no clear trends. Annealing tests show that the material is stable after annealing at 500 °C for 1 h, but not after annealing at 800 °C for 1 h. In combination, these results suggest that sputtered Cr–C/Ag films could be potentially applicable for electric contact applications.
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| 7. |
- Hallberg, Pär, et al.
(author)
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Genetic variants associated with angiotensin-converting enzyme inhibitor-induced cough : a genome-wide association study in a Swedish population
- 2017
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In: Pharmacogenomics (London). - : FUTURE MEDICINE LTD. - 1462-2416 .- 1744-8042. ; 18:3, s. 201-213
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Journal article (peer-reviewed)abstract
- Aim: We conducted a genome-wide association study on angiotensin-converting enzyme inhibitor-induced cough and used our dataset to replicate candidate genes iden-tified in previous studies. Patients & methods: A total of 124 patients and 1345 treated controls were genotyped using Illumina arrays. The genome-wide significance level was set to p < 5 x 10(-8). Results: We identified nearly genome-wide significant associations in CLASP1, PDE11A, KCNMB2, TGFA, SLC38A6 and MMP16. The strongest association was with rs62151109 in CLASP1 (odds ratio: 3.97; p = 9.44 x 10(-8)). All top hits except two were located in intronic or noncoding DNA regions. None of the candidate genes were significantly associated in our study. Conclusion: Angiotensin-converting enzyme inhibitor-induced cough is potentially associated with genes that are independent of bradykinin pathways.
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| 8. |
- Johansson Persson, Anna, et al.
(author)
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A high intake of dietary fiber influences C-reactive protein and fibrinogen, but not glucose and lipid metabolism, in mildly hypercholesterolemic subjects.
- 2014
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In: European Journal of Nutrition. - : Springer Science and Business Media LLC. - 1436-6215 .- 1436-6207. ; 53:1, s. 39-48
-
Journal article (peer-reviewed)abstract
- PURPOSE: The aim of the study was to investigate how a diet high in dietary fiber, with several fiber sources included, modulates glucose and lipid metabolism and the inflammatory response in humans. METHODS: Subjects (n = 25) aged 58.6 (1.1) years (mean and SD) with a BMI of 26.6 (0.5) kg/m(2) and a total cholesterol (TC) of 5.8 (0.1) mmol/L (mean and SEM) were given a high fiber (HF) and low fiber (LF) diet, in a randomized controlled 5-week crossover intervention, separated by a 3-week washout. The HF diet consisted of oat bran, rye bran, and sugar beet fiber incorporated into test food products; one bread roll, one ready meal, and two beverages consumed daily. Equivalent food products, without added fibers, were provided in the LF diet. RESULTS: Total dietary fiber intake was 48.0 g and 30.2 g per day for the HF and LF diet, respectively. Significant reduction in C-reactive protein (CRP) was observed between the diets (P = 0.017) and a significant reduction in fibrinogen within the HF diet (P = 0.044). There were no significant effects in other measured circulating cytokines or in glucose, insulin, and lipid levels. CONCLUSIONS: Our study suggests that a 5-week high dietary fiber intake of oat bran, rye bran, and sugar beet fiber might reduce the low-grade inflammatory response measured as CRP which could, together with reduced fibrinogen, help to prevent the risk of cardiovascular disease.
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| 9. |
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| 10. |
- Johansson Persson, Anna, et al.
(author)
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LC-QTOF/MS metabolomic profiles in human plasma after a 5-week high dietary fiber intake.
- 2013
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In: Analytical and Bioanalytical Chemistry. - : Springer Science and Business Media LLC. - 1618-2642 .- 1618-2650. ; 405:14, s. 4799-4809
-
Journal article (peer-reviewed)abstract
- The objective was to investigate the alterations of plasma metabolome profiles to identify exposure and effect markers of dietary fiber intake. Subjects (n = 25) aged 58.6 (1.1) years (mean and SD) with a body mass index of 26.6 (0.5) kg/m(2) were given a high fiber (HF) and a low fiber (LF) diet, in a 5-week randomized controlled crossover intervention. The HF diet consisted of oat bran, rye bran, and sugar beet fiber incorporated into test food products, whereas the LF diet was made of equivalent food products to the HF diet, but without adding fibers. Blood plasma samples were collected at the start and end of each intervention period and analyzed by LC-QTOF/MS. In total, 6 features in positive mode and 14 features in negative mode were significantly different between the HF and the LF diet (p < 0.01, q < 0.05). Two markers, 2,6-dihydroxybenzoic acid and 2-aminophenol sulfate, were increased after HF diet, along with a tentatively identified saponin derived from oat avenacosides. The untargeted metabolomics approach enabled the identification of two new markers of dietary fiber intake in human plasma. Further studies will be needed to verify if these markers could serve as compliance markers of fiber intake.
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| 11. |
- Kmoch, Laura, 1987, et al.
(author)
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Access mapping highlights risks from land reform in upland Myanmar
- 2021
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In: Journal of Land Use Science. - 1747-4248 .- 1747-423X. ; 16:1, s. 34-54
-
Journal article (peer-reviewed)abstract
- Secure land access is vital for Myanmar's upland households, who rely on crops and forests to meet their subsistence needs. But recent land reforms threaten to undermine customary tenure and land-use practices in Myanmar. This paper combines income accounting methods with access theory to assess how new legislation may affect four Chin communities in the country's north-west. Our assessment of 94 households' land-access mechanisms and economic benefits from different types of land reveals existing land-access inequalities among Chin households and demonstrates communities' continued dependence on environmental resources, especially those from swidden fields, home gardens and forests. A majority of households would lose all of their land-derived income, if they were denied access to communities' customarily governed land, e.g., under the Vacant, Fallow and Virgin Land Management Law. Policy stakeholders should therefore intervene, to alleviate land-access inequalities among Chin households and to direct Myanmar's land-system dynamics onto more just development trajectories.
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| 12. |
- Kmoch, Laura, 1987, et al.
(author)
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Cyclone Komen’s aftermath: Local knowledge shows how poverty and inequalities fuel climate risk in western Myanmar
- 2021
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In: Regional Environmental Change. - : Springer Science and Business Media LLC. - 1436-378X .- 1436-3798. ; 21:4
-
Journal article (peer-reviewed)abstract
- Cyclones and other extreme events exert increasing pressure on South-East Asia’s societies and put smallholder farmers at risk. Here, we draw on participatory causal-diagramming workshops, interviews and survey data, to provide contextually grounded knowledge about rural communities’ exposure and vulnerability to climate-related hazards in western Myanmar. By tracing how the 2015 cyclone Komen led to a prolonged humanitarian disaster, we show that climate-related risks in this area arise from the complex interplay of households’ pre-existing vulnerabilities, persistent farming challenges, extensive disasters and cascading effects, which disparately affect lowland and upland communities. The different household strata’s dissimilar vulnerabilities vis-à-vis Komen’s impacts were rooted in the distinct exposure of their production systems to landslides and floods. Pre-existing land-access barriers, land-degradation processes, climatic stressors, agricultural pests and diseases, and chronic lack of assets and food insecurity further mediated households’ vulnerability. Relief interventions did not stop the disaster’s escalation, although this could have been achieved with early technical and material assistance to address the cyclone’s impacts on farmers’ land. Targeted aid for households facing imminent food insecurity or debt crisis could have lessened engagement in precarious coping strategies and distress migration. A diversification of households’ livelihood and land-use practices and increased redundancies of critical assets and infrastructure could help to mitigate future cyclone-triggered disasters. By demonstrating the strengths of local knowledge approaches in untangling the complex interplay of extreme events with households’ everyday vulnerabilities and agricultural land-use practices, we make a case for more contextually grounded disaster risk and climate adaptation research.
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| 13. |
- Kmoch, Laura, 1987, et al.
(author)
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Upland Livelihoods between Local Land and Global Labour Market Dependencies: Evidence from Northern Chin State, Myanmar
- 2018
-
In: Sustainability. - : MDPI AG. - 2071-1050. ; 10:10
-
Journal article (peer-reviewed)abstract
- Livelihoods and agrarian change processes across upland South-East Asia have been explored for decades. Yet, knowledge gaps remain about contemporary livelihood strategies and land dependence in areas previously inaccessible to academic research, such as in upland Myanmar. Moreover, new strands of inquiry arise with continued globalisation, e.g., into the effects of remittances and labour migration on household incomes and livelihoods in distant upland areas. This study applied clustering techniques to income accounts of 94 households from northern Chin State, Myanmar to: (i) Identify households’ livelihood strategies; (ii) assess their dependence on access to land and natural resources; and (iii) compare absolute and relative incomes across strategies. We show that households engaged in six relatively distinct livelihood strategies: Relying primarily on own farming activities; making a living off the land with mixed income from agriculture and forest resources; engaging in wage employment; living from remittances; practicing non-forest tree husbandry; or engaging in self-employed business activities. We found significant income inequalities across clusters, with households engaging in remittance and wage-oriented livelihood strategies realizing higher incomes than those primarily involved in land-based activities. Our findings point to differentiated vulnerabilities associated with the identified livelihood strategies—to climate risks, shifting land-governance regimes and labour market forces.
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| 14. |
- Mosén, Henrik, et al.
(author)
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A study of structural and heart characteristics in male triathletes compared to normals
- 2006
-
Conference paper (peer-reviewed)abstract
- Normal hjärtfunktion hos förstorade idrottshjärtan – en MR-studie av manliga elittriatleters hjärtan Henrik Mosén1, Mathilda Eliasson1, Marcus Carlsson1, Andreas Persson1, Torsten Buhre2 och Håkan Arheden1. Avdelningen för klinisk fysiologi, Universitetssjukhuset i Lund1, Idrottsvetenskap, Malmö högskola2. Bakgrund: Endast ett fåtal studier av uthållighetstränade elitidrottares hjärtan har gjorts med kardiovaskulär MR-teknik (CMR). Tidigare studier har ofta använt ekokardiografi som undersökningsmodalitet, men MR-tekniken är i många avseenden en bättre metod när särskild exakthet i mätningar och mycket god reproducerbarhet är önskvärd. Syftet med studien var därför att med modern CMR-teknik jämföra elitidrottares hjärtan med hjärtan hos normalt tränade personer, med avseende på struktrella och funktionella parametrar. Metod: 13 svenska manliga elittriatleter, 33,3 5,7 år gamla, genomförde ett maximalt arbetsprov med gasanalys för att fastställa deras arbetsfysiologiska status. Hjärtparametrarna studerades med moderna MR-sekvenser, som steady state free precession (SSFP). Studien gjordes som 4 delstudier, där målet var att klargöra om man kan finna några hjärtfysiologiska skillnader mellan elitidrottarna och normaltränade individer. Vänsterkammarmassa (LVM), vänsterkammarvolymer och cardiac index (CI) studerades. Dessutom gjordes mätningar av total hjärtvolym (THV) och total hjärtvolymsvariation (THVV) hos elitidrottarna, något som inte gjorts tidigare. Resultat: CI var något, men inte signifikant (p = 0,10), förhöjt hos elitidrottarna jämfört med normala. LVM och slutdiastoliska och slutsystoliska volymer var högre än referensvärden för åldersmatchade normala, men ejektionsfraktionen hos idrottarna skilde sig inte från de normalas. Idrottarna hade en signifikant (p<0,001) större THV men skilde sig inte från normaler vad gäller THVV. Sammanfattning: Vi konstaterar att hjärtat hos de uthållighetstränade elitidrottare vi studerat skiljer sig från normala hjärtan vad gäller storleken, där både vänsterkammaren såväl som hela hjärtat är större hos elitidrottarna. Vad gäller funktionen är den helt normal vad gäller alla studerade parametrar, vilket kan tolkas som att förstoringen av idrottshjärtat är en väl balanserad anpassning till högre krav på hjärtat som pump.
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| 15. |
- Munksgaard Persson, Matilda, et al.
(author)
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HIF-2 alpha Expression Is Suppressed in SCLC Cells, Which Survive in Moderate and Severe Hypoxia When HIF-1 alpha Is Repressed
- 2012
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In: American Journal of Pathology. - : Elsevier. - 0002-9440 .- 1525-2191. ; 180:2, s. 494-504
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Journal article (peer-reviewed)abstract
- Small cell lung carcinoma (SCLC) is extremely aggressive and frequently metastasizes widely in its early stage. Because tumor hypoxia is related to aggressive tumor behavior and the hypoxic adaptation of SCLC is poorly documented, we stained SCLC tumors arranged in a tissue microarray for hypoxia-inducible factor (HIF)-1 alpha and HIF-2 alpha proteins. We found an overall lack of HIF-2 alpha protein expression, which was confirmed in large tumor sections. HIF-1 alpha protein was strongly expressed in most tumors, frequently adjacent to necrotic regions. In concordance, cultured SCLC but not non-small cell lung carcinoma cells showed no or extremely low levels of HIF-2 alpha mRNA and no HIF-2 alpha protein at hypoxia. HIF-1 alpha was stabilized after 4 hours at hypoxia, and its accumulation increased up to 96 hours. SCLC cells survived well and showed net proliferation and low cell death in modest (1% oxygen) and severe (0.1% oxygen) hypoxia. HIF-1 alpha repression virtually did not influence cell death or viability despite reduced levels of hypoxia-inducible genes, such as BNIP3 and BNIP3L. At 1% oxygen no increased autophagy (LC3B-II activation) or NF-kappa B signaling were detected, whereas the unfolded protein response was activated at severe hypoxia. Our data indicate that HIFs are not exclusively required for SCLC cell survival at modest or severe hypoxia and that additional, yet uncharacterized, hypoxia-driven adaptation pathways may become activated.
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| 16. |
- Nilsson, Anna Matilda, et al.
(author)
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Mixed Airway and Pulmonary Parenchymal Disease in Patients With Primary Sjögren Syndrome : A 6-year Follow-up
- 2021
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In: Journal of Rheumatology. - Toronto, Canada : Journal Of Rheumatology Publishing Co. - 0315-162X .- 1499-2752. ; 48:2, s. 232-240
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Journal article (peer-reviewed)abstract
- To assess pulmonary function and chronic obstructive pulmonary disease (COPD) development over time in patients with primary Sjögren syndrome (pSS), as well as the association between pulmonary function, radiographic findings, respiratory symptoms, and clinical features of pSS, taking cigarette consumption into account.
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| 17. |
- Pettersson, Helen, et al.
(author)
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Arsenic trioxide is highly cytotoxic to small cell lung carcinoma cells.
- 2009
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In: Molecular Cancer Therapeutics. - 1538-8514 .- 1535-7163. ; 8:1, s. 160-170
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Journal article (peer-reviewed)abstract
- Small cell lung carcinoma (SCLC) is an extremely aggressive form of cancer and current treatment protocols are insufficient. SCLC have neuroendocrine characteristics and show phenotypical similarities to the childhood tumor neuroblastoma. As multidrug-resistant neuroblastoma cells are highly sensitive to arsenic trioxide (As2O3) in vitro and in vivo, we here studied the cytotoxic effects of As2O3 on SCLC cells. As2O3 induced pronounced cell death in SCLC cells at clinically relevant concentrations, and also at hypoxia. SCLC cells were more sensitive than non-SCLC cells to As2O3. Cell death was mainly due to necrosis, although apoptotic responses were also seen. A significant in vivo effect of As2O3 on SCLC growth was shown in a nude mice-xenograft model, although a fraction of the treated tumor-bearing animals did not respond. The nonresponding SCLC tumors differed in morphology and cell organization compared with treatment-responsive tumors, which in turn, showed decreased vascularization and higher expression of neuroendocrine markers compared with control tumors. Our results suggest a potential clinical application of As2O3 in SCLC therapy. In addition to cell death induction, antiangiogenic induction of differentiation may also be part of the in vivo effect of As2O3 on SCLC growth, as suggested by an increase in neuroendocrine markers in cultured cells.
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| 18. |
- Sahi, Maryam, et al.
(author)
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Profiling of Surface Protein Epitopes on Viral Particles by Multiplex Dual-Reporter Strategy
- 2024
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In: Journal of Visualized Experiments. - : MyJove Corporation. - 1940-087X. ; 2024:203
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Journal article (peer-reviewed)abstract
- Membrane proteins on enveloped viruses play an important role in many biological functions involving virus attachment to target cell receptors, fusion of viral particles to host cells, host-virus interactions, and disease pathogenesis. Furthermore, viral membrane proteins on virus particles and presented on host cell surfaces have proven to be excellent targets for antivirals and vaccines. Here, we describe a protocol to investigate surface proteins on intact severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) particles using the dual-reporter flow cytometric system. The assay exploits multiplex technology to obtain a triple detection of viral particles by three independent affinity reactions. Magnetic beads conjugated to recombinant human angiotensin-converting enzyme-2 (ACE2) were used to capture viral particles from the supernatant of cells infected with SARS-CoV-2. Then, two detection reagents labeled with R-phycoerythrin (PE) or Brilliant Violet 421 (BV421) were applied simultaneously. As a proof-of-concept, antibody fragments targeting different epitopes of the SARS CoV-2 surface protein Spike (S1) were used. The detection of viral particles by three independent affinity reactions provides strong specificity and confirms the capture of intact virus particles. Dose-dependency curves of SARS-CoV-2 infected cell supernatant were generated with replicate coefficient variances (mean/SD) ˂14%. Good assay performance in both channels confirmed that two virus surface target protein epitopes are detectable in parallel. The protocol described here could be applied for (i) high-multiplex, high-throughput profiling of surface proteins expressed on enveloped viruses; ii) detection of active intact viral particles; and (iii) assessment of specificity and affinity of antibodies and antiviral drugs for surface epitopes of viral antigens.The application can be potentially extended to any type of extracellular vesicles and bioparticles, exposing surface antigens in body fluids or other liquid matrices.
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| 19. |
- Thomsen, Hanna, 1989, et al.
(author)
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Increased antibiotic efficacy and noninvasive monitoring of Staphylococcus epidermidis biofilms using per-cysteamine-substituted γ-cyclodextrin - A delivery effect validated by fluorescence microscopy.
- 2020
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In: International journal of pharmaceutics. - : Elsevier BV. - 1873-3476 .- 0378-5173. ; 587
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Journal article (peer-reviewed)abstract
- Limited and poor delivery of antibiotics is cited as one reason for the difficulty in treating antibiotic-resistant biofilms associated with chronic infections. We investigate the effectiveness of a positively charged, single isomer cyclodextrin derivative, octakis[6-(2-aminoethylthio)-6-deoxy]-γ-CD (γCys) to improve the delivery of antibiotics to biofilms. Using multiphoton laser scanning microscopy complemented with super-resolution fluorescence microscopy, we showed that γCys tagged with fluorescein (FITC) is uniformly distributed throughout live S. epidermidis biofilm cultures in vitro and results suggest it is localized extracellularly in the biofilm matrix. NMR spectroscopic data in aqueous solution confirm that γCys forms inclusion complexes with both the antibiotics oxacillin and rifampicin. Efficacy of γCys/antibiotic (oxacillin and rifampicin) was measured in the biofilms. While treatment with γCys/oxacillin had little improvement over oxacillin alone, γCys/rifampicin reduced the biofilm viability to background levels demonstrating a remarkable improvement over rifampicin alone. The strong synergistic effect for γCys/rifampicin is at this stage not clearly understood, but plausible explanations are related to increased solubility of rifampicin upon complexation and/or synergistic interference with components of the biofilm. The results demonstrate that designed cyclodextrin nanocarriers, like γCys, efficiently deliver suitable antibiotics to biofilms and that fluorescence microscopy offers a novel approach for mechanistic investigations.
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| 20. |
- Tijani, Muyideen Kolapo, et al.
(author)
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How to Detect Antibodies Against Babesia divergens in Human Blood Samples
- 2024
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In: Open Forum Infectious Diseases. - : OXFORD UNIV PRESS INC. - 2328-8957. ; 11:2
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Journal article (peer-reviewed)abstract
- Background. Today only indirect fluorescent antibody assays (IFAs) are commercially available to detect antibodies against Babesia divergens in humans. IFA is subjective and requires highly experienced staff. We have therefore developed an enzyme-linked immunosorbent assay (ELISA)-based method for measuring anti-B. divergens immunoglobulin G antibodies in human blood samples. Methods. Crude merozoite extract from in vitro cultures of a new B. divergens isolate was used in ELISA to detect antibodies in different sets of samples: Borrelia burgdorferi-positive samples, healthy individuals, tick-bitten individuals including follow-up samples 3 months later, positive control samples from patients with an active Babesia infection, and samples from malaria-endemic regions. As a reference, IFA was used to detect antibodies in the tick-bitten samples. Western blot was used to evaluate reactions against specific bands in extracts with/without parasites. Results. Using IFA as the reference method, the sensitivity and specificity of the ELISA were 86% (12/14) and 100% (52/52). There was a very high correlation (r = -0.84; P = .0004) between IFA dilution factors and ELISA absorbances among the samples classified as positive. Five percent of the B. burgdorferi-positive samples were judged as weakly positive and 5% as strongly positive in our ELISA. Western blot showed that the immunodominant antigens (∼120 kDa) were from merozoites and not from erythrocytes. Conclusions. This ELISA can detect antibodies directed against B. divergens, and it can be a useful and easy assay to handle compared with IFA. The ELISA can also measure high and low levels of antibodies, which could give insight into the recency of a B. divergens infection.
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| 21. |
- Ulmius, Matilda, et al.
(author)
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An oat branmeal influences blood insulin levels and related gene sets in peripheral blood mononuclear cells of healthy subjects
- 2011
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In: Genes & Nutrition. - : Springer Science and Business Media LLC. - 1555-8932 .- 1865-3499. ; 6:4, s. 429-439
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Journal article (peer-reviewed)abstract
- The understanding of how fibre-rich meals regulate molecular events at a gene level is limited. This pilot study aimed to investigate changes in gene expression in peripheral blood mononuclear cells (PBMCs) from healthy subjects after consumption of an oat bran-rich meal. Fifteen subjects (8 men and 7 women, aged 20-28 years) ingested meals with oat bran or a control meal after an overnight fast. Blood samples for analysis of postprandial glucose, insulin and triglyceride concentrations were taken during 3 h, while PBMCs for microarray gene expression profiling from five men and five women were taken before and 2 h after the meal. Analysis of transcriptome data was performed with linear mixed models to determine differentially expressed genes in response either to meal intake or meal content, and enrichment analysis was used to identify functional gene sets responding to meal intake and specifically to oat bran intake. Meal intake as such affected gene expression for genes mainly involved in metabolic stress; indicating increased inflammation due to the switch from fasting to fed state. The oat bran meal affected gene sets associated with a lower insulin level, compared with the control meal. The gene sets included genes involved in insulin secretion and β-cell development, but also protein synthesis and genes related to cancer diseases. The oat bran meal also significantly lowered postprandial blood insulin IAUC compared to control. Further studies are needed to compare these acute effects with the long-term health effects of oat bran.
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| 22. |
- Ulmius, Matilda, et al.
(author)
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Gastrointestinal Release of beta-Glucan and Pectin Using an In Vitro Method
- 2011
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In: Cereal Chemistry. - 0009-0352. ; 88:4, s. 385-390
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Journal article (peer-reviewed)abstract
- The release of soluble dietary fiber is a prerequisite for viscous effects and hence beneficial health properties. A simple in vitro method was adapted to follow the release during gastrointestinal digestion, and the percentage of solubilized fiber was measured over time. beta-Glucan from oat bran was mainly released during gastric digestion while the release of pectin from sugar beet fiber continued in the small intestine. Unmilled fractions of sugar beet fiber released more soluble fiber than oat bran flakes, probably due to the porous structure of sugar beet fiber as a result of manufacturing processes, but also clue to differences in source. Milling to smaller fiber particles significantly improved releasability (from 20 to 55% released beta-glucan and from 50 to 70% released pectin, respectively, after digestion). When milled fibers were included in individual food matrices, the release was reduced by protein and starch matrices (5% beta-glucan and 35% pectin released, respectively) and slowed by fat (45% beta-glucan and 60% pectin released). This may result in a too low or too late release in the upper small intestine to be able to interfere with macronutrient uptake. The method may be suitable for predicting the gastrointestinal release of soluble dietary fibers from food matrices in the development of healthy food products.
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| 23. |
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| 24. |
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| 25. |
- Ulmius, Matilda, et al.
(author)
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The influence of dietary fibre source and gender on the postprandial glucose and lipid response in healthy subjects.
- 2009
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In: European Journal of Nutrition. - : Springer Science and Business Media LLC. - 1436-6215 .- 1436-6207. ; 48, s. 395-402
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Journal article (peer-reviewed)abstract
- BACKGROUND: Consumption of soluble dietary fibre is correlated with decreased postprandial glucose and insulin responses and hence has beneficial effects on the metabolic syndrome. AIM OF THE STUDY: To investigate the effects on postprandial glucose, insulin and triglyceride concentrations of meals enriched with soluble dietary fibres from oats, rye bran, sugar beet fibre or a mixture of these three fibres. METHODS: Thirteen healthy human volunteers (6 men and 7 women, aged 20-28 years) were included in the study. The subjects came to the study centre once a week after an overnight fast to ingest test meals and a control meal in random order. The meals contained either oat powder (62 g, of which 2.7 soluble fibre), rye bran (31 g, of which 1.7 g soluble fibre), sugar beet fibre (19 g, of which 5 g soluble fibre), a mixture of these three fibres (74 g, of which 1.7 g soluble fibre from each source, giving 5 g soluble fibre) or no added fibre (control) and were all adjusted to contain the same total amount of available carbohydrates. Blood samples were drawn before and every 30 min up to 180 min after the meals. RESULTS: Meals with rye bran gave a lower postprandial glucose peak when compared with the control meal, and this effect was more pronounced in women compared to men. Oat powder, containing a low amount of total fibre and a high amount of carbohydrates in liquid matrix, gave a higher incremental glucose peak concentration compared to rye bran and sugar beet fibre and higher insulin incremental area under curve compared to control. The oat powder also influenced the effects of the mixed meal, diminishing the glucose-lowering effects. Postprandial triglyceride levels tended to be higher after all fibre-rich meals, but only significant for oat powder and the mixed meal when compared with the control meal. CONCLUSIONS: Postprandial glucose, insulin and triglyceride concentrations are influenced by dietary fibre-rich meals, depending on fibre source, dose of soluble and total fibre and possibly gender.
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| 26. |
- Zirath, Hanna, et al.
(author)
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MYC inhibition induces metabolic changes leading to accumulation of lipid droplets in tumor cells
- 2013
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In: Proceedings of the National Academy of Sciences. - : Proceedings of the National Academy of Sciences. - 1091-6490 .- 0027-8424. ; 110:25, s. 10258-10263
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Journal article (peer-reviewed)abstract
- The MYC genes are the most frequently activated oncogenes in human tumors and are hence attractive therapeutic targets. MYCN amplification leads to poor clinical outcome in childhood neuroblastoma, yet strategies to modulate the function of MYCN do not exist. Here we show that 10058-F4, a characterized c-MYC/Max inhibitor, also targets the MYCN/Max interaction, leading to cell cycle arrest, apoptosis, and neuronal differentiation in MYCN-amplified neuroblastoma cells and to increased survival of MYCN transgenic mice. We also report the discovery that inhibition of MYC is accompanied by accumulation of intracellular lipid droplets in tumor cells as a direct consequence of mitochondrial dysfunction. This study expands on the current knowledge of how MYC proteins control the metabolic reprogramming of cancer cells, especially highlighting lipid metabolism and the respiratory chain as important pathways involved in neuroblastoma pathogenesis. Together our data support direct MYC inhibition as a promising strategy for the treatment of MYC-driven tumors.
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| 27. |
- Önning, Gunilla, et al.
(author)
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Nutrigenomik: Metoder för att undersöka hur gener påverkar kostens hälsoeffekter
- 2008
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In: Nordisk Nutrition. - 1654-8337. ; :3, s. 26-28
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Journal article (pop. science, debate, etc.)abstract
- Hälsoeffekter av näringsämnen har traditionellt undersökts genom att analysera en eller ett fåtal fysiologiska markörer, exempelvis blodkolesterolnivå. Med nutrigenomik blir det möjligt att ta ett större grepp om hur kosten påverkar vår hälsa och även koppla det till individens genuppsättning.
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