Whole-exome sequencing in patients with maturation arrest: a potential additional diagnostic tool for prevention of recurrent negative testicular sperm extraction outcomes.

STUDY QUESTION: Could whole-exome sequencing (WES) be useful in clinical practice for men with maturation arrest (MA) after a first testicular sperm extraction (TESE)? SUMMARY ANSWER: WES in combination with TESE yields substantial additional information and may potentially be added as a test to predict a negative outcome of a recurrent TESE in patients with MA. WHAT IS KNOWN ALREADY: At present, the only definitive contraindications for TESE in men with non-obstructive azoospermia (NOA) are a 46,XX karyotype and microdeletions in the azoospermia factor a (AZFa) and/or AZFb regions. After a first negative TESE with MA, no test currently exists to predict a negative outcome of a recurrent TESE. STUDY DESIGN, SIZE, DURATION: In a cohort study, we retrospectively included 26 patients with idiopathic NOA caused by complete MA diagnosed after a first TESE. PARTICIPANTS/MATERIALS, SETTING, METHODS: Twenty-six men with MA at the spermatocyte stage in all seminiferous tubules, according to a histopathological analysis performed independently by two expert histologists, and a normal karyotype (i.e. no AZF gene microdeletions on the Y chromosome) were included. Single-nucleotide polymorphism comparative genomic hybridization array and WES were carried out. The results were validated with Sanger sequencing. For all the variants thought to influence spermatogenesis, we used immunohistochemical techniques to analyse the level of the altered protein. MAIN RESULTS AND THE ROLE OF CHANCE: Deleterious homozygous variants were identified in all seven consanguineous patients and in three of the 19 non-consanguineous patients. Compound heterozygous variants were identified in another 5 of the 19 non-consanguineous patients. No recurrent variants were identified. We found new variants in genes known to be involved in azoospermia or MA [including testis expressed 11 (TEX11), meiotic double-stranded break formation protein 1 (MEI1), proteasome 26s subunit, ATPase 3 interacting protein (PSMC3IP), synaptonemal complex central element protein 1 (SYCE1) and Fanconi anaemia complementation group M (FANCM) and variants in genes not previously linked to human MA (including CCCTC-binding factor like (CTCFL), Mov10 like RISC complex RNA helicase 1 (MOV10L1), chromosome 11 open reading frame 80 (C11ORF80) and exonuclease 1 (EXO1)]. LARGE SCALE DATA: Data available on request. LIMITATIONS, REASONS FOR CAUTION: More data are required before WES screening can be used to avoid recurrent TESE, although screening should be recommended for men with a consanguineous family background. WES is still a complex technology and can generate incidental findings. WIDER IMPLICATIONS OF THE FINDINGS: Our results confirmed the genetic aetiology of MA in most patients: the proportion of individuals with at least one pathologic variant was 50% in the overall study population and 100% in the consanguineous patients. With the exception of MEI1 (compound heterozygous variants of which were identified in two cases), each variant corresponded to a specific gene-confirming the high degree of genetic heterogeneity in men with MA. Our results suggest that WES screening could help to avoid recurrent, futile TESE in men with MA in general and in consanguineous individuals in particular, but these results need to be confirmed in future studies before clinical implementation. STUDY FUNDING/COMPETING INTEREST(S): The study was funded by the Fondation Maladies Rares (Paris, France), Merck (Kenilworth, NJ, USA), IRSF (Montigny le Bretonneux, France) and Agence de la Biomédecine (Saint Denis, France). There are no competing interests. TRIAL REGISTRATION NUMBER: N/A.

Resolving the apparent transmission paradox of African sleeping sickness.

Human African trypanosomiasis (HAT), or African sleeping sickness, is a fatal disease found throughout sub-Saharan Africa. The disease is close to elimination in many areas, although it was similarly close to elimination once before and subsequently reemerged, despite seemingly low rates of transmission. Determining how these foci persisted and overcame an apparent transmission paradox is key to finally eliminating HAT. By assessing clinical, laboratory, and mathematical data, we propose that asymptomatic infections contribute to transmission through the presence of an overlooked reservoir of skin-dwelling parasites. Our assessment suggests that a combination of asymptomatic and parasitaemic cases is sufficient to maintain transmission at foci without animal reservoirs, and we argue that the current policy not to treat asymptomatic HAT should be reconsidered.

Biennial surveillance of Plasmodium falciparum anti-malarial drug resistance markers in Democratic Republic of Congo, 2017 and 2019.

BACKGROUND: Because of the loss of chloroquine (CQ) effectiveness, the Democratic Republic of Congo (DRC)'s malaria treatment policy replaced CQ by sulfadoxine-pyrimethamine (SP) as first-line treatment of uncomplicated malaria in 2003, which in turn was replaced by artemisinin-based combination therapies (ACT) in 2005. The World Health Organization (WHO) recommends monitoring of anti-malarial drug resistance every 2 years. The study aimed to provide baseline data for biennial molecular surveillance of anti-malarial drug resistance by comparing data from a study conducted in 2019 to previously published data from a similar study conducted in 2017 in the DRC. METHODS: From July to November 2019, a cross-sectional study was conducted in ten sites which were previously selected for a similar study conducted in 2017 across the DRC. P. falciparum malaria was diagnosed by a rapid diagnostic test (RDT) or by microscopy and dried blood samples (DBS) were taken from patients who had a positive test. Segments of interest in pfcrt and pfk13 genes were amplified by conventional PCR before sequencing. RESULTS: Out of 1087 enrolled patients, 906 (83.3%) were PCR-confirmed for P. falciparum. Like in the 2017-study, none of the mutations known to be associated with Artemisinine (ART) resistance in Southeast Asia was detected. However, non-synonymous (NS) mutations with unknown functions were observed among which, A578S was detected in both 2017 and 2019-studies. The overall prevalence of pfcrt-K76T mutation that confers CQ-resistance was 22.7% in 2019-study compared to 28.5% in 2017-study (p-value = 0.069), but there was high variability between sites in the two studies. Like in 2017-study, the pfcrt 72-76 SVMNT haplotype associated with resistance to amodiaquine was not detected. CONCLUSION: The study reported, within 2 years, the non-presence of molecular markers currently known to be associated with resistance to ART and to AQ in P. falciparum isolated in the DRC. However, the presence of polymorphisms with as-yet unknown functions was observed, requiring further characterization. Moreover, an overall decrease in the prevalence of CQ-resistance marker was observed in the DRC, but this prevalence remained highly variable from region to region.

Determinants of the use of contraceptive methods by adolescents in the Democratic Republic of the Congo: results of a cross-sectional survey.

BACKGROUND: Family planning (FP) is an effective strategy to prevent unintended pregnancies of adolescents. We aimed at identifying the socio-demographic factors underlying the low use of contraceptive methods by teenage girls in the Democratic Republic of the Congo (DRC). METHODS: A secondary analysis targeting teenage girls aged 15-19 was carried out on the Performance, Monitoring and Accountability project 2020 (PMA 2020) round 7 data, collected in Kinshasa and Kongo Central provinces. The dependent variable was the "use of contraceptive methods by sexually active teenage girls", calculated as the proportion of teenagers using modern, traditional or any contraceptive methods. Independent variables were: level of education, age, province, religion, marital status, number of children, knowledge of contraceptive methods and household income. Pearson's chi-square and logistic regression tests helped to measure the relationship between variables at the alpha significance cut point of 0.05. RESULTS: A total of 943 teenagers were interviewed; of which 22.6, 18.1 and 19.9% ​​used any contraceptive method respectively in Kinshasa, Kongo Central and overall. The use of modern contraceptive methods was estimated at 9.9, 13.4 and 12.0% respectively in Kinshasa, Kongo Central and overall. However, the use of traditional methods estimated at 8.0% overall, was higher in Kinshasa (12.7%) and lower (4.7%) in Kongo Central (p < .001). Some factors such as poor knowledge of contraceptive methods (aOR = 8.868; 95% CI, 2.997-26.240; p < .001); belonging to low-income households (aOR = 1.797; 95% CI, 1.099-2.940; p = .020); and living in Kongo central (aOR = 3.170; 95% CI, 1.974-5.091; p < .001) made teenagers more likely not to use any contraceptive method. CONCLUSION: The progress in the use of contraceptive methods by adolescent girls is not yet sufficient in the DRC. Socio-demographic factors, such as living in rural areas, poor knowledge of FP, and low-income are preventing teenagers from using FP methods. These findings highlight the need to fight against such barriers; and to make contraceptive services available, accessible, and affordable for teenagers.

The use of contraceptive methods remains low among adolescents aged 15 to 19 in the Democratic Republic of the Congo. However, family planning (FP) methods can help to prevent unintended pregnancies. This study aimed at identifying the socio-demographic factors that prevent teenage girls from using FP methods. We analyzed the data from the Performance, Monitoring and Accountability project (PMA 2020), seventh round, collected in Kinshasa and Kongo Central provinces. The use of contraceptive methods by sexually active adolescents was measured according to the level of education, age, province, religion, marital status, number of children, knowledge of contraceptive methods and household income. For the 943 adolescent girls interviewed, the use of any contraceptive method was calculated at 22.6, 18.1 and 19.9%, respectively in Kinshasa, Kongo Central and overall. The use of traditional methods was estimated at 8.0% overall, higher in Kinshasa (12.7%) and lower (4.7%) in Kongo Central. However, the use of modern contraceptive methods was estimated at 9.9, 13.4 and 12.0% respectively in Kinshasa, Kongo Central and overall. Poor knowledge of contraceptive methods; low-income and living in Kongo central province were the factors associated with the low use of any contraceptive method. In conclusion, the progress in the use of contraceptive methods by adolescent girls is not yet sufficient, due to some socio-demographic barriers. These results suggest to fight against such factors; and to make contraceptive services available, accessible, and affordable for teenagers.

Assessment of Plasmodium falciparum anti-malarial drug resistance markers in pfk13-propeller, pfcrt and pfmdr1 genes in isolates from treatment failure patients in Democratic Republic of Congo, 2018-2019.

BACKGROUND: The national policy for malaria treatment of the Democratic Republic of Congo recommends two first-line artemisinin-based combinations for the treatment of uncomplicated malaria: artesunate-amodiaquine and artemether-lumefantrine. This study investigated the presence of markers associated with resistance to the current first-line artemisinin-based combination therapy (ACT) in isolates of Plasmodium falciparum from treatment failure patients in the Democratic Republic of Congo. METHODS: From November 2018 to November 2019, dried blood spots were taken from patients returning to health centres for fever within 28 days after an initial malaria treatment in six sentinel sites of the National Malaria Control Programme across Democratic Republic of Congo. The new episode of malaria was first detected by a rapid diagnostic test and then confirmed by a real-time PCR assay to define treatment failure. Fragments of interest in pfk13 and pfcrt genes were amplified by conventional PCR before sequencing and the Pfmdr1 gene copy number was determined by a TaqMan real-time PCR assay. RESULTS: Out of 474 enrolled patients, 364 (76.8%) were confirmed positive by PCR for a new episode of P. falciparum malaria, thus considered as treatment failure. Of the 325 P. falciparum isolates obtained from 364 P. falciparum-positive patients and successfully sequenced in the pfk13-propeller gene, 7 (2.2%) isolates carried non-synonymous mutations, among which 3 have been previously reported (N498I, N554K and A557S) and 4 had not yet been reported (F506L, E507V, D516E and G538S). Of the 335 isolates successfully sequenced in the pfcrt gene, 139 (41.5%) harboured the K76T mutation known to be associated with chloroquine resistance. The SVMNT haplotype associated with resistance to amodiaquine was not found. None of the isolates carried an increased copy number of the pfmdr1 gene among the 322 P. falciparum isolates successfully analysed. CONCLUSION: No molecular markers currently known to be associated with resistance to the first-line ACT in use were detected in isolates of P. falciparum from treatment failure patients. Regular monitoring through in vivo drug efficacy and molecular studies must continue to ensure the effectiveness of malaria treatment in Democratic Republic of Congo.

Molecular surveillance of anti-malarial drug resistance in Democratic Republic of Congo: high variability of chloroquinoresistance and lack of amodiaquinoresistance.

BACKGROUND: The loss of chloroquine (CQ) effectiveness has led to its withdrawal from national policies as a first-line treatment for uncomplicated malaria in several endemic countries, such as the Democratic Republic of Congo (DRC). The K76T mutation on the pfcrt gene has been identified as a marker of CQ resistance and the SVMNT haplotype in codons 72-76 on the same gene has been associated with resistance to amodiaquine (AQ). In the DRC, the prevalence of K76T has decreased from 100% in 2000 to 63.9% in 2014. The purpose of this study was to determine the prevalence of K76T mutations in circulating strains of Plasmodium falciparum, 16 years after CQ withdrawal in the DRC and to investigate the presence of the SVMNT haplotype. METHODS: In 2017, ten geographical sites across the DRC were selected. Dried blood samples were collected from patients attending health centres. Malaria was first detected by a rapid diagnostic test (RDT) available on site (SD Bioline Malaria Ag Pf or CareStart Malaria Pf) or thick blood smear and then confirmed by a P. falciparum species-specific real-time PCR assay. A pfcrt gene segment containing a fragment that encodes amino acids at positions 72-76 was amplified by conventional PCR before sequencing. RESULTS: A total of 1070 patients were enrolled. Of the 806 PCR-confirmed P. falciparum positive samples, 764 were successfully sequenced. The K76T mutation was detected in 218 samples (28.5%; 95% CI 25.4%-31.9%), mainly (96%) with the CVIET haplotype. Prevalence of CQ resistance marker was unequally distributed across the country, ranging from 1.5% in Fungurume to 89.5% in Katana. The SVMNT haplotype, related to AQ resistance, was not detected. CONCLUSION: Overall, the frequency of the P. falciparum CQ resistance marker has decreased significantly and no resistance marker to AQ was detected in the DRC in 2017. However, the between regions variability of CQ resistance remains high in the country. Further studies are needed for continuous monitoring of the CQ resistance level for its prospective re-use in malaria management. The absence of the AQ resistance marker is in line with the use of this drug in the current DRC malaria treatment policy.

Prevalence and risk factors of metabolic syndrome in HIV-infected adults at three urban clinics in a post-conflict setting, eastern Democratic Republic of the Congo.

OBJECTIVE: To determine the prevalence of and risk factors for metabolic syndrome (MS) in HIV-infected adults at three urban clinics in Bukavu, Democratic Republic of the Congo. DESIGN: Cross-sectional study. METHODS: From July to September 2016, baseline socio-demographics, risk factors and clinical characteristics were collected using a structured questionnaire or extracted from medical records. Fasting blood sugar and lipids were measured. MS was defined per the National Cholesterol Education Program (NCEP) Adult Treatment Panel III (ATP III) and the International Diabetes Federation (IDF) criteria. Adjusted odds ratio (OR) was generated through multivariate logistic regression models. RESULTS: Of 495 participants, 356 (72%) were women and 474 (95.8%) were receiving antiretroviral therapy (ART). The median age (years) [interquartile range (IQR)] was 43 [36-51]. The overall prevalence of MS per NECP/ATP III and IDF criteria was 27% [95% CI: 20-35%] or 30% [95% CI: 23-38%], respectively. In a multivariate logistic regression, low physical activity (OR 2.47, 95% CI: 1.40-4.36); daily exposure to biomass fuel smoke (BMF) for more than 2 h (OR 2.18, 95% CI: 1.01-4.68); protease inhibitor containing ART (OR: 2.96, 95% CI: 1.07-8.18); and stavudine-containing ART regimen (OR: 2.57, 95% CI: 1.11-5.93) were independently associated with MS. CONCLUSIONS: MS was highly prevalent in this hospital-based study population. Beside known traditional risk factors and contribution of specific ART regimens to MS, daily exposure to BMF is new and of specific concern, necessitating targeted urgent prevention and management interventions.

EG-VEGF controls placental growth and survival in normal and pathological pregnancies: case of fetal growth restriction (FGR).

Identifiable causes of fetal growth restriction (FGR) account for 30 % of cases, but the remainders are idiopathic and are frequently associated with placental dysfunction. We have shown that the angiogenic factor endocrine gland-derived VEGF (EG-VEGF) and its receptors, prokineticin receptor 1 (PROKR1) and 2, (1) are abundantly expressed in human placenta, (2) are up-regulated by hypoxia, (3) control trophoblast invasion, and that EG-VEGF circulating levels are the highest during the first trimester of pregnancy, the period of important placental growth. These findings suggest that EG-VEGF/PROKR1 and 2 might be involved in normal and FGR placental development. To test this hypothesis, we used placental explants, primary trophoblast cultures, and placental and serum samples collected from FGR and age-matched control women. Our results show that (1) EG-VEGF increases trophoblast proliferation ([(3)H]-thymidine incorporation and Ki67-staining) via the homeobox-gene, HLX (2) the proliferative effect involves PROKR1 but not PROKR2, (3) EG-VEGF does not affect syncytium formation (measurement of syncytin 1 and 2 and ß hCG production) (4) EG-VEGF increases the vascularization of the placental villi and insures their survival, (5) EG-VEGF, PROKR1, and PROKR2 mRNA and protein levels are significantly elevated in FGR placentas, and (6) EG-VEGF circulating levels are significantly higher in FGR patients. Altogether, our results identify EG-VEGF as a new placental growth factor acting during the first trimester of pregnancy, established its mechanism of action, and provide evidence for its deregulation in FGR. We propose that EG-VEGF/PROKR1 and 2 increases occur in FGR as a compensatory mechanism to insure proper pregnancy progress.

Ultrasensitive analyses of zearalenone in grain samples with a catalytic oxidation platform involving gold nanomaterials.

Zearalenone (ZEN) contamination in cereals poses a serious threat to human and animal health, yet existing rapid test methods still suffer from poor stability and low sensitivity. The studied sensor reduces inspection time while enabling applications for on-site grain inspection. Specifically, a ZEN detector that can sensitively detect ZEN content in grains was developed. Ion implantation is an effective method for modifying screen-printed electrodes (SPEs). Gold nanoparticles (AuNPs; 5-10 nm) were uniformly implanted using screen-printed electrodes as a catalytic oxidation medium to generate an electrochemical sensor. The surface structure of the modified electrode was characterized using scanning electron microscopy and X-ray photoelectron spectroscopy. The results showed that differential pulse voltammetry had good linear electrochemical response to ZEN at 10 ng/kg to 10 mg/kg, with a detection limit of 1.1 ng/kg. We used AuNP-SPE sensors to detect ZEN in grain samples such as maize and oats.

Enrichment efficiency of lutein in eggs and its function in improving fatty liver hemorrhagic syndrome in aged laying hens.

In this study, we evaluated the enrichment efficiency of lutein in eggs and its function in preventing fatty liver hemorrhagic syndrome (FLHS) in aged laying hens. Five groups of laying hens (65 wk old) were fed basal diets supplemented with 0, 30, 60, 90, or 120 mg/kg of lutein. The supplementation period lasted 12 wk followed by 2 wk of lutein depletion in feed. The results revealed that lutein efficiently enriched the egg yolks and improved their color with a significant increase in relative redness (P < 0.001). Lutein accumulation increased in the egg yolk until day 10, then depletion reached a minimum level after 14 d. Overall, zeaxanthin content in all the groups was similar throughout the experimental period. However, triglycerides and total cholesterol were significantly decreased in the liver (P < 0.05) but not significantly different in the serum (P > 0.05). In the serum, the lipid metabolism enzyme acetyl-CoA synthetase was significantly reduced (P < 0.05), whereas dipeptidyl-peptidase 4 was not significantly different (P > 0.05), and there was no statistical difference of either enzyme in the liver (P > 0.05). Regarding oxidation and inflammation-related indexes, malondialdehyde, tumor necrosis factors alpha, interleukin-6, and interleukin-1 beta were decreased, whereas superoxide dismutase and total antioxidant capacity increased in the liver (P < 0.001). The function of lutein for the same indexes in serum was limited. It was concluded that lutein efficiently enriched the egg yolk of old laying hens to improve their color and reached the highest level on day 10 without being subject to a significant conversion into zeaxanthin. At the same time, lutein prevented liver steatosis in aged laying hens by exerting strong antioxidant and anti-inflammatory functions, but also through the modulation of lipid metabolism, which may contribute to reducing the incidence of FLHS in poultry.

Carotenoid enrichment in eggs: From biochemistry perspective.

The emergence of safe and functional eggs for consumer acceptance has gained focus. The production of carotenoid-enriched eggs has received attention due to its multifunctional biological properties. Nutritional modification of laying hens' diet can be a strategy to produce such eggs. This review presents the chemistry of carotenoids in nature and eggs, the accumulation process of carotenoids into eggs, and the functions of carotenoids in eggs. Our findings showed that carotenoids can be deposited into the egg and contribute to improving its nutritive value. The biosynthesis, chemical structure, and metabolism pathways of carotenoids lead to the deposition of carotenoids into eggs in their original or metabolized forms. Also, some factors modulate the efficiency of carotenoids in fowls before accumulation into eggs. Carotenoid-enriched eggs may be promising, ensuring the availability of highly nutritive eggs. However, further studies are still needed to comprehend the full metabolism process and the extensive functions of carotenoids in eggs.

Matrix metalloproteinase-9 and intercellular adhesion molecule 1 are powerful staging markers for human African trypanosomiasis.

OBJECTIVES: A critical step before treatment of human African trypanosomiasis (HAT) is the correct staging of the disease. As late stage is established when trypanosomes cross the blood-brain barrier and invade the central nervous system, we hypothesized that matrix metalloproteinases and cell adhesion molecules could indicate, alone or in combination, the disease progression from the first to the second stage of HAT. METHODS: We measured the levels of MMP-2, MMP-9, ICAM-1, VCAM-1 and E-selectin in the cerebrospinal fluid (CSF) of 63 Trypanosoma brucei gambiense-infected patients (15 stage 1 and 48 stage 2). Staging was based on counting of white blood cells (WBC) and/or parasite detection in CSF. Concentrations were obtained either by ELISA or multiplex bead suspension assays, and results were compared with three known HAT staging markers (CXCL10, CXCL8 and H-FABP). RESULTS: ICAM-1 and MMP-9 accurately discriminated between stage 1 and stage 2 patients with HAT with 95% sensitivity (SE) for 100% specificity (SP), which was better than CXCL10 (93% SE for 100% SP), one of the most promising known markers. Combination of ICAM-1 and MMP-9 with H-FABP provided a panel that resulted in 100% of SE and SP for staging HAT. CONCLUSIONS: ICAM-1 and MMP-9, alone or in combination, appeared as powerful CSF staging markers of HAT. Final validation of all newly discovered staging markers on a large multi-centric cohort including both forms of the disease as well as patients with others infections should be performed.

Assessment of Response to Moderate and High Dose Supplementation of Astaxanthin in Laying Hens.

In this study, we evaluated the impact of moderate and high dose dietary supplementation of astaxanthin on production performance, quality of eggs, and health status of laying hens. The experiment involved 480 laying hens, divided into four groups of eight replicates. The different groups named A1, A2, A3, and A4 were allocated the same diet supplemented with Haematococcus pluvialis powder to provide 0, 21.3, 42.6, and 213.4 mg of astaxanthin per kilogram of feed, respectively. One-way ANOVA and linear and quadratic regression analysis were used to assess the differences between the groups. The results showed that the production performance of laying hens and the physical quality of eggs did not significantly differ between the groups (p > 0.05). Astaxanthin distribution in tissues was typical per bird, whereas the egg yolk coloration and astaxanthin concentration increased with the supplementation dose (p < 0.001). However, there was a decrease in concentration and coloration efficacy of astaxanthin at high dose supplementation (213.4 mg/kg) compared to moderate doses (21.3 and 42.6 mg/kg). Blood biochemical tests showed some discrepancies that were not ascribed to the effect of diets, and the increase in liver weight in the A4 group compared to others was equated with an adaptation of laying hens to the high dose supplementation. Astaxanthin improved superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities and diminished malondialdehyde (MDA) content in both liver and serum; meanwhile, the activities of SOD and GSH-Px in serum were similar between the moderate doses and high dose supplementation. Additionally, astaxanthin alleviated interleukin 2, 4, and 6 (IL-2, IL-4, and IL-6, respectively) in serum, showing the best effect in A3 and A4 groups. Besides, immunoglobulin G and M (IgG and IgM), as well as tumor necrosis factor-alpha and beta (TNF-α and TNF-ß), were not much affected. It was concluded that although astaxanthin has no obvious adverse effect on the performance and health status of laying hens, it may not be valuable for egg fortification and health status improvement of laying hens at high dose supplementation. The high dose astaxanthin supplementation up to 213.4 mg/kg in the diet might be avoided.

Evaluation of the Elecsys SARS-CoV-2 antigen assay for the detection of SARS-CoV-2 in nasopharyngeal swabs.

AIMS: The aim of this study was to evaluate the performance of the automated Elecsys® SARS-CoV-2 antigen assay compared to RT-PCR taken as the gold standard for SARS-CoV-2 detection. METHODS: 225 nasopharyngeal swabs were randomly collected among which 123 were tested positive and 102 negatives for SARS-CoV-2 based on RT-PCR. Antigen dosing were performed on a Cobas 8000 e801 analyzer. RESULTS: The antigen test diagnosed SARS-CoV-2 infection status with an overall sensitivity of 65,85% (95% CI 56,76-74,16%), a specificity of 100% (95% CI 96,49-100%) with a Cut-off value ≥ 1. When the cut-off value for the antigen assay was set to > 0,673 COI, the accuracy reached its highest level with a sensitivity of 74,8% (95% CI 66,2 - 82,2%) and a specificity of 97,1% (95% CI 91,6 - 99,4%). Imprecision was estimated in accordance with manufacturer's claims. CONCLUSIONS: We obtained an overall sensitivity of 65,85% (95% CI 56,76-74,16%) and a specificity of 100% (95% CI 96,49-100%), slightly higher than the results reported by the manufacturer. Yet, it remains relatively low comparatively to what is generally acceptable for these antigenic assays (a relative sensitivity of 80%). We also noticed that the accuracy could reach its highest level if the cut-off is set above 0,673 which is lower than established by the manufacturer. Thus, our results suggest that the Elecsys® SARS-CoV-2 Antigen assays, should be improved prior to be used in a SARS-Cov-2 screening strategy. However, if one antigenic assay could demonstrate acceptable performance, it might be centralized in clinical laboratories, keeping the RT-PCR in a second phase for confirmation.

Effect of Replacing in-Feed Antibiotic Growth Promoters with a Combination of Egg Immunoglobulins and Phytomolecules on the Performance, Serum Immunity, and Intestinal Health of Weaned Pigs Challenged with Escherichia coli K88.

The study was conducted to investigate the effects of replacing antibiotic growth promoters (AGPs) with an egg immunoglobulin (IgY) combined with phytomolecules (PM) on the growth rate, serum immunity, and intestinal health of weaned pigs challenged with Escherichia coli K88 (E. coli K88). A total of 192 piglets were weaned at 28 days old with an average weight of 7.29 (± 0.04) kg. They were randomly divided into four treatments containing eight replicates with six piglets per replicate. The treatment groups were NC and PC fed a basal diet, AGP fed a basal diet supplemented with 75 mg/kg chlortetracycline, 50 mg/kg oxytetracycline calcium, and 40 mg/kg zinc bacitracin, IPM fed a basal diet supplemented with IgY at dose of 2.5 g/kg and 1.0 g/kg and PM at dose of 300 mg/kg and 150 mg/kg during days 1 to 17 and 18 to 42, respectively. On days 7 to 9 of the experiment, piglets in the PC, AGP, and IPM groups were orally challenged with 20 mL E. coli K88 (109 CFU/mL), while piglets in the NC group were challenged with 20 mL medium without E. coli K88. The E. coli K88 challenge model was successful as the incidence of post-weaning diarrhea (PWD) of piglets challenged with E. coli K88 was significantly higher than that of those unchallenged piglets during the challenge time (days 7 to 9) and days 1 to 7 of post-challenge (p < 0.05). A diet with combinations of IgY and PM and AGPs significantly decreased the incidence of PWD during the challenge time and days 1 to 7 of post-challenge (p < 0.05) compared to the PC group and significantly improved the ratio of feed to weight gain (F:G) during days 1 to 17 of the experiment compared to the NC and PC groups (p < 0.05). In comparison with the PC group, piglets in the IPM group had significantly higher serum levels of IgA, IgG, and IgM (p < 0.05), but lower serum IL-1ß on day 17 of experiement (p < 0.05). Besides, diet supplementation with AGP significantly decreased serum IL-1ß, IL-6, and TNF-α on days 17 and 42 (p < 0.05) with comparison to the PC group. Piglets in the IPM group showed a significantly lower level of fecal coliforms (p < 0.05), but a higher villus height of jejunum and ileum and higher ratio of villus height to crypt depth of duodenum and jejunum (p < 0.05) than those piglets in the PC group. In summary, diet supplementation with a mixture of IgY and PM decreased the incidence of PWD and coliforms, increased feed conversion ratio, and improved intestinal histology and immune function.

Effects of duration and supplementation dose with astaxanthin on egg fortification.

Long-term and graded dose of astaxanthin supplementation in laying hen's diet was assessed for egg fortification. Five groups of laying hens with 8 replications each were fed for 24 wk with diet supplemented astaxanthin at 0 mg/kg (control), 7.1 mg/kg, 14.2 mg/kg, 21.3 mg/kg, and 42.6 mg/kg (Basal, A7, A14, A21, and A42, respectively). The performance of laying hens, egg quality, astaxanthin concentration as well as conversion efficiency and geometric isomers proportion in yolks were assessed on wk 8 and 24. One-way analysis of variance (ANOVA) and linear and quadratic regression analyses were used to evaluate the dose effect. In parallel, the Student's t test compared the values between wk 8 and wk 24 of test within a group. Overall, the results revealed that neither production performance nor egg physical quality was affected by astaxanthin dose level and feeding duration. Following the supplementation dose, the redness of yolks (a*) increased (P < 0.001). But, the a* score in A42 (23.48) was just 3-folds the a* score in A7 (8.89). Concentration of astaxanthin in eggs was dose-level dependent showing a linear relationship (P < 0.001) with a slight declination observed in all groups on wk 24 compared to wk 8. The deposition rate of astaxanthin into egg yolk was higher in A21 and A42. The proportion of geometric isomers in egg yolk were not affected by the feeding duration. As the supplementation dose increased, all-trans isomer proportion gradually decreased in the egg yolk, while 13-cis isomer proportion rose. It was concluded that astaxanthin is an efficient carotenoid for egg fortification, which can be supplemented in diet up to 42.6 mg/kg for 24 wk without compromising the performance of laying hens or physical quality of eggs. This appreciably affects the egg yolk color and confers a better accumulation of total astaxanthin and cis isomers into eggs as the supplementation dose increases.

Spatial and molecular mapping of Pfkelch13 gene polymorphism in Africa in the era of emerging Plasmodium falciparum resistance to artemisinin: a systematic review.

The spread of Plasmodium falciparum isolates carrying mutations in the kelch13 (Pfkelch13) gene associated with artemisinin resistance (PfART-R) in southeast Asia threatens malaria control and elimination efforts. Emergence of PfART-R in Africa would result in a major public health problem. In this systematic review, we investigate the frequency and spatial distribution of Pfkelch13 mutants in Africa, including mutants linked to PfART-R in southeast Asia. Seven databases were searched (PubMed, Embase, Scopus, African Journal Online, African Index Medicus, Bioline, and Web of Science) for relevant articles about polymorphisms of the Pfkelch13 gene in Africa before January, 2019. Following PRISMA guidelines, 53 studies that sequenced the Pfkelch13 gene of 23 100 sample isolates in 41 sub-Saharan African countries were included. The Pfkelch13 sequence was highly polymorphic (292 alleles, including 255 in the Pfkelch13-propeller domain) but with mutations occurring at very low relative frequencies. Non-synonymous mutations were found in only 626 isolates (2·7%) from west, central, and east Africa. According to WHO, nine different mutations linked to PfART-R in southeast Asia (Phe446Ile, Cys469Tyr, Met476Ile, Arg515Lys, Ser522Cys, Pro553Leu, Val568Gly, Pro574Leu, and Ala675Val) were detected, mainly in east Africa. Several other Pfkelch13 mutations, such as those structurally similar to southeast Asia PfART-R mutations, were also identified, but their relevance for drug resistance is still unknown. This systematic review shows that Africa, thought to not have established PfART-R, reported resistance-related mutants in the past 5 years. Surveillance using PfART-R molecular markers can provide valuable decision-making information to sustain the effectiveness of artemisinin in Africa.

Effects of 17beta-estradiol on preadipocyte proliferation in human adipose tissue: Involvement of IGF1-R signaling.

Estrogens are known to stimulate the proliferation of human preadipocytes. However, the molecular mechanisms underlying the increased cell growth by these steroids are poorly understood. In the present study, we have demonstrated that the proliferative effect of 17beta-estradiol involves the induction of both cell cycle gene expressions, c-myc and cyclin D1. Moreover, the mitogenic effects of 17beta-estradiol are suppressed by the pure antagonist ICI 182780 suggesting that estradiol action is mediated by estrogen receptor (ER). We have also shown that 17beta-estradiol is able to inhibit human preadipocyte apoptosis capacity as reflected by DNA fragmentation experiments and the mRNA expression of the pro- and antiapoptotic genes. Finally, 17beta-estradiol significantly induces both mRNA and protein expression of RIGF1 in human preadipose cells via ER and thus reinforces the signaling pathway of the proliferative factor, IGF1. Taken together, these data reinforce the concept of cross-talk between IGF1- and ER-signaling pathways in preadipocytes and indicate that IGFI may be a critical regulator of estrogen-mediated preadipose growth.

Improved localization of cellular membrane receptors using combined fluorescence microscopy and simultaneous topography and recognition imaging.

The combination of fluorescence microscopy and atomic force microscopy has a great potential in single-molecule-detection applications, overcoming many of the limitations coming from each individual technique. Here we present a new platform of combined fluorescence and simultaneous topography and recognition imaging (TREC) for improved localization of cellular receptors. Green fluorescent protein (GFP) labeled human sodium-glucose cotransporter (hSGLT1) expressed Chinese Hamster Ovary (CHO) cells and endothelial cells (MyEnd) from mouse myocardium stained with phalloidin-rhodamine were used as cell systems to study AFM topography and fluorescence microscopy on the same surface area. Topographical AFM images revealed membrane features such as lamellipodia, cytoskeleton fibers, F-actin filaments and small globular structures with heights ranging from 20 to 30 nm. Combined fluorescence and TREC imaging was applied to detect density, distribution and localization of YFP-labeled CD1d molecules on alpha-galactosylceramide (alphaGalCer)-loaded THP1 cells. While the expression level, distribution and localization of CD1d molecules on THP1 cells were detected with fluorescence microscopy, the nanoscale distribution of binding sites was investigated with molecular recognition imaging by using a chemically modified AFM tip. Using TREC on the inverted light microscope, the recognition sites of cell receptors were detected in recognition images with domain sizes ranging from approximately 25 to approximately 160 nm, with the smaller domains corresponding to a single CD1d molecule.

[Pulmonary involvement in the course of cytomegalovirus infection in an immunocompetent adult]. / Atteinte pulmonaire au cours d'une infection à Cytomegalovirus chez un adulte immunocompétent.

INTRODUCTION: Cytomegalovirus (CMV) infection in the immunocompetent is generally silent or it may present as a mononucleosis like syndrome but, rarely, it can lead to symptomatic manifestations. CASE REPORT: An immunocompetent and previously healthy 43- year-old woman presented with fever, dyspnoea, liver cell necrosis and a mononucleosis syndrome. The CT scan showed diffuse ground-glass opacity. BAL and blood cultures were sterile. Urinary antigens (Legionella pneumophila, Streptococcus pneumoniae) and serology for atypical respiratory pathogens (Mycoplasma pneumoniae and Chlamydia sp.) were negative. A diagnosis of CMV pneumonia was established on serology (presence of anti-CMV IgM) and PCR detection of viral DNA in the serum. Without antiviral therapy, there was a favourable clinical outcome 1 week later and 1 month later the CT scan was normal. CONCLUSION: CMV infection can lead, exceptionally. to a hypoxic pneumonia in the immunocompetent host. Antiviral therapy should not be prescribed systematically.