Enzyme-linked Fluorescent Assay Research Articles

Performance of the Enzyme Linked Fluorescent Assay in Diagnosis of HIV Infection; Comparative Evaluation with other Methods.

Our study aimed to investigate the role of the enzyme linked fluorescent assay (ELFA) method in the diagnosis of Human Immunodeficiency Virus (HIV) infection by comparing it with enzyme-linked immunosorbent assay (ELISA) and chemiluminescent microplate immunoassay (CMIA) methods and its role in the HIV diagnostic algorithm and to update the recommended algorithm for HIV testing. We evaluated 101 HIV-reactive and 101 HIV-negative specimens. All samples were studied with the methods of anti HIV1/2 test micro-ELISA, ELFA, and CMIA. At the same time, HIV RNA PCR and western blot (WB)/rapid immunochromatographic test (RICT) were also studied with the same samples. All HIV RNA and WB positive samples (n = 101) were positive with micro-ELISA, CMIA and ELFA. Twenty-five negative samples of HIV RNA and WB were positive with micro-ELISA and CMIA, while just 6 samples were positive with ELFA. When all samples were evaluated together, the false positivity rate of the ELFA method was found to be 5.9%, and the false positivity rates of the micro-ELISA and CMIA methods were determined to be 31.7% and 30.7%, respectively. It was determined that there is a high level of agreement between the ELFA method and confirmation tests. It was thought that it might take place in the preconfirmation stage. As can be seen from the results obtained, the false positive rate by ELFA method was found to be about five times lower than that of micro-ELISA and CMIA methods. Considering that antigen (p24) and antibody positivity can be given separately with this aspect, it can be considered that there is a confirmation place in HIV diagnosis algorithm.

Seroprevalence of SARS-CoV-2 among the Healthcare Workers of a Tertiary Care Hospital of Northeast India during First Wave of COVID-19 Pandemic: A Hospital-based Cross-sectional Study

Introduction: During Coronavirus Disease-2019 (COVID19) pandemic, Healthcare Workers (HCWs) are the frontline personals who are engaged in different facilities of the health system. So they always remain at a greater risk of exposure and acquiring the disease. They may also become a potential source of infection to the other patients as well to the community. Aim: To estimate the seroprevalence of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-COV-2) specific Immunoglobulin G (IgG) antibodies among asymptomatic, COVID-19 negative HCWs of a tertiary care hospital. Materials and Methods: This hospital-based cross-sectional study was conducted in the Department of Microbiology in a tertiary care hospital of North-East India. A total of 215 HCWs were recruited from 15th October to 14th December 2020 after taking written and informed consent. Inclusion criteria were: a) >18 years of age and both genders, b) asymptomatic, negative for COVID19 either by Rapid Antigen Test (RAT) or Reverse Transcription Polymerase Chain Reaction (RT-PCR), c) working in the hospital for atleast last four months. Predesigned questionnaire was used for data collection. Serum samples were tested for SARSCoV-2 IgG antibodies by Enzyme Linked Fluorescence Assay (ELFA) using VIDAS (VITEK ImmunoDiagnostic Assay System) platform. Chi-square test was used (Epi Info version 7 software) for data analysis. Results: The prevalence of SARS-COV-2 IgG was 54 (25.12%) out of 215, which was highest in ≤30 years age group, 27 (32.14 %) out of 84 (p=0.0261). Significant seropositivity was found among cleaners 22 (61.11%) out of 36 (p<0.01) and participants who reported having COVID-19-related symptoms in the previous months (p<0.013). However gender, daily patient contact, close contact with COVID-19 cases and working in COVID-19 units showed no significance. Conclusion: The study highlighted a high burden of asymptomatic SARS-CoV-2 infection among HCWs. A proper surveillance system is needed for estimating the burden of COVID-19 among HCWs as well as in the community for better understanding of the dynamics of the infection.

Determination of Low IgG Class Antibody Avidity Percentage by IgM Levels Specific to Toxoplasma Gondii.

Ig (Immunglobulin) M detection and low avidity index are markers of recent infection in differentiating acute and chronic stages of Toxoplasma gondii (T. gondii) infections. In this study, we aimed to evaluate whether the anti-T. gondii IgM antibody index threshold value could be a predictive factor in the estimation of low avidity and its use in improving the diagnosis of early toxoplasma infection. Anti-T. gondii IgM, IgG antibody and IgG avidity results were analyzed. Anti-T. gondii IgG and IgM antibodies in blood samples were studied with chemiluminescent microparticle immunoassay (CMIA), and IgG avidity test was performed with Enzyme Linked Fluorescent Assay (ELFA) technique. The overall seroprevalence of anti-T. gondii antibodies (IgG and/or IgM) was 19.4%. Of the 64 patients whose avidity tests were studied, 47 (73.4%) were female. Twenty seven (57.4%) of the women were pregnant. In the IgG avidity test, 7.8% low avidity was detected. Low avidity was detected in only 4 (15.4%) of 26 IgM positive cases. IgM analysis of a case (6-month-old baby) with low avidity was found to be negative. In the prediction of low avidity, the assay's IgM positivity cutoff value was ≥ 0.6, its sensitivity, specificity, positive predictive value, and negative predictive value were 80%, 62.7%, 2.3%, and 99.7%, respectively. With Architect, 37.3% of samples were false positive. Determining the IgM index cutoff value was unsuccessful in distinguishing low avidity. The area under the ROC curve was 0.574 (p = 0.60). In our study, the positive predictive value of the IgM test kit in estimating low avidity was low and the false positivity rate was 37.3%. It is thought that the index cutoff value of the anti-T. gondii IgM antibody test kit cannot be considered as a good predictor of recent infection. Studies with larger patient groups are needed.

Procena nivoa testosterona, dehidroepiandrosterona i prolaktina kod parova sa sterilitetom inficiranih i neinficiranih parazitom Toxoplasma gondii, koji su posećivali Centar za lečenje steriliteta Fatma Al-Zahra u Babolu, u Iranu

Introduction/Aims: Toxoplasmosis modifies various hormones and cytokines in the infected hosts which may result in several disorders. This study was conducted to assess testosterone, DHEA, and prolactin concentration levels among Toxoplasma gondii infected and uninfected infertile couples. Methods: Blood samples were collected and sera were separated. The sera were analyzed for the detection of anti-Toxoplasma (IgG& IgM) antibodies using commercial ELISA kits. The level of DHEA was measured by ELISA and the levels of testosterone and prolactin were evaluated by enzyme-linked fluorescent assay (ELFA, VIDAS). Results: The overall seroprevalence of toxoplasmosis was 58.0% (218/376). Among women, 56.9% (107/188) and 6.5% (7/107) were positive for anti-T. gondii antibodies IgG and IgM, respectively. The IgG and IgM were detected in the sera of 111/188 (59.0%) and 9/111 (8.1%) in male subjects, respectively. A positive association was observed between T. gondii infection and the upper and lower ranges of the normal value of testosterone in males (x 2 = 6.8, p = 0.033) but not in females (x 2 = 0.62, p = 0.99). A positive correlation was seen between toxoplasmosis and the upper and lower ranges of the normal value of prolactin in females (x 2 = 6.5, p = 0.039) but not in male cases (x 2 = 1.06, p = 0.59). Conclusion: Our results demonstrated no statistically significant differences between the level of sexual hormones between Toxoplasma-infected individuals and Toxoplasma-free subjects suffering from infertility. These findings suggest that further studies should be performed on infertile cases with large sample sizes in a case-control format.

Evaluation of Staphylococcus aureus growth and staphylococcal enterotoxin production in delicatessen and fine bakery products

Staphylococcal food poisoning is one of the most prevalent causes of foodborne intoxication worldwide. Sandwiches and desserts are susceptible to contamination by S. aureus due to the high proportion of manual work during their production. Our study aimed to evaluate the impact of storage conditions on staphylococcal enterotoxin production in sandwiches and buttercream puffs. Foods were inoculated with different S. aureus strains capable of producing type A, B, and C staphylococcal enterotoxins and incubated at 15, 25, and 30 °C. During the storage, samples were analysed for S. aureus counts and for staphylococcal enterotoxins. An enzyme-linked fluorescence assay was used to detect staphylococcal enterotoxins. The influence of inappropriate storage on S. aureus growth and staphylococcal enterotoxin production was evaluated. No staphylococcal enterotoxins were detected in sandwiches stored for 72 h at any of the tested temperatures. In buttercream puffs, enterotoxins type A, B, and C were detected within 24 h of storage at 25 °C.

Performance of immunochromatographic and immunoenzymatic techniques in the diagnosis of toxoplasmosis in pregnant women in Cameroon: need for harmonization.

in order to contribute to the improvement of the management of toxoplasmosis in pregnant women in Cameroon, performance of two techniques commonly used in the diagnosis of toxoplasmosis was evaluated. a total of 541 pregnant women were recruited from seven hospitals in two Regions of Cameroon, of which 63% (341: Batch1) were from health facilities (HF) using a immunochromatographic technique (ICT) as a screening test for toxoplasmosis, and 37% (200: Batch2) from those using an immunoenzymatic technique (IEZ). On each sample, Ig (Immunoglobulin) G (IgG) and IgM were tested by three techniques: a Rapid Diagnostic Test (RDT), an Enzyme Linked Immuno Sorbent Assay (ELISA) and a Vidas Enzyme-linked fluorescent assay taken as reference (VIDAS/ELFA). The results from the health facilities were recorded. for the IgG assay, our two laboratory methods were sensitive (96.0% and 97.5%) and specific (64.2% and 59.7%). Their concordance rates with the VIDAS/ELFA reference were above 60% (P<0.001). Moreover, for the IgM assay, the performances of the two methods were equivalent: Se= 18.2%, Sp= 99.4% with a low concordance rate (Kappa = 0.24). Considering the results provided by the selected hospitals, the ELISA used in Batch2 showed similar performances to the two techniques used in reference lab while the performances were low for the RDT used in Batch1. both methods showed similar performances (good for (IgG) and poor for IgM). However, for the immunochromatographic method, differences in performance were found between our results and those provided by the selected health facilities. These differences suggest a harmonization of diagnostic techniques for toxoplasmosis in pregnant women in Cameroonian health facilities.

Correlation of Vitamin D Levels with Polycystic Ovary Syndrome: A Cross-sectional Study

Objective: To compare vitamin D status in, women with PCOS &amp; fertile women without PCOS and its subsequent evaluation.&#x0D; Introduction: PCOS is an endocrine disorder of women in reproductive age, characterised by obesity, hyperandrogenaemia and insulin resistance. Women with PCOS tend to be overweight and have increased risk of development of Type II Diabetes and cardiovascular disease. Exact Etiology of PCOS still remain an enigmatic dilemma however various studies conducted till date include diet and lifestyle modification as the key factor to promote health, BMI, reduced hyperinsulinemia and reduce the risk of development of PCOS.&#x0D; Main aim of our study was to compare vitamin D status in women having PCOS, with fertile women in a tertiary care hospital in Uttarakhand.&#x0D; Methodology: The conducted study was cross sectional, involving the enrolment of 100 women comprising of 50 women with PCOS and 50 fertile women without PCOS. Participants were selected from gynaecological OPD at Shri Mahant Indiresh Hospital, associated with Shri Guru Ram Rai Institute of Medical Sciences, Dehradun from July 2019 to January 2020. The diagnostic criteria of PCOS used was the Rotterdam criteria. The serum 25-hydroxy vitamin D and other metabolic markers were measured. Vitamin D deficiency was defined as serum 25 (OH) D concentrations less than 20 ng/ml measured on an instrument named as miniVidas (BioMerieux, Germany) based on ELFA (enzyme linked fluorescent assay).&#x0D; Results: Serum 25-hydroxyvitamin D was significantly lower in women with PCOS compared to fertile controls (p&lt; 0.0001), and the prevalence rates of 25(OH) D deficiency and insufficiency were higher in women with PCOS than in fertile women (p &lt; 0.0001). The study results showed that the prevalence of 25 (OH) D deficiencies in PCOS women was significantly high. Serum 25 (OH) D concentrations were significantly negatively correlated with body mass index (BMI), waist-to-hip ratio (WHR), fasting insulin, total cholesterol and low-density lipoprotein cholesterol (LDL-C), (P &lt; 0.05). In comparison, serum 25 (OH) D concentrations were significantly positively correlated with high-density lipoprotein cholesterol (HDL-C) (P &lt; 0.05). Increased BMI and WHR, high levels of fasting insulin, total cholesterol and LDL-C were regarded as risk factors, but high level of HDL-C was considered to be protective factor of vitamin D deficiency in PCOS women.&#x0D; Conclusion: The study demonstrated that women with PCOS have a significantly lower 25(OH) D compared to fertile controls. A compromised vitamin D status in PCOS women is associated with a higher prevalence and metabolic risk of PCOS in women.

Correlation between Cytomegalovirus (CMV) Infection in Children with Cerebral Palsy (CP) and Future Anxiety among Parents

One of the causes of Cerebral Palsy (CP) is a viral infection in the mother during pregnancy. The most recorded infections were Cytomegalovirus (CMV) infections. Inappropriate parenting can affect the psychological condition of CP children. Psychological conditions that are not good can cause the child's immune system to decrease and increase the risk of CMV reactivation. This is one factor in the emergence of parental anxiety about the future sustainability of their CP children. It was to determine the relationship of anti-cytomegalovirus (CMV) Immunoglobulin G in children with CP with future anxiety among parents. The design of this study used a cross-sectional approach that using CP children and their parents. Serological examination used the ELFA (Enzyme-Linked Fluorescent Assay) method for 40 CP children and a questionnaire on the future anxiety of parents of children with special needs were answered directly by the parents of CP children, 40 fathers and 40 mothers. Analysis of the research data used Spearman Rank. The results of this study found an anti-CMV IgG seropositive relationship in CP children with future anxiety in fathers (p-value = 0.022; a 0.05) and mothers (p-value = 0.011; a 0.05). If anxiety in parents has not good treatment, it will impact the care of CP children, the developmental progress of CP children will not optimal.

Prevalence of HIV and hepatitis B virus among pregnant women in Luanda (Angola): geospatial distribution and its association with socio-demographic and clinical-obstetric determinants

BackgroundHIV and HBV infections remain responsible for high rate of morbidity and mortality in many African Countries, affecting women and newborns. This study aims to analyze the spatial pattern of HIV and HBV infections in pregnant women in Luanda, Angola, and the statistical association between HIV and HBV and socio-economic characteristics, hygiene, and health status.MethodsDetection of anti-HIV antibodies (total anti-HIV-1, anti-HIV-2 and HIV-1 p24 antigen) and Hepatitis B antigens (HBsAg, HBeAg) and antibodies (anti-HBc Total II, HBc IgM, Anti-HBsT II) was performed by Enzyme Linked Fluorescent Assay (ELFA) in serum samples of 878 pregnant women attended at the Lucrecia Paim Maternity Hospital (LPMH). Data were collected by questionnaire after written consent, and spatial distribution was assessed through a Kernel Density Function. The potential risk factors associated with HIV HBV infection were evaluated using bivariate and multivariate binomial logistic regression analysis.ResultsAnti-HIV antibodies were positive in 118 samples (13.4%) and HBV infection were positive in 226 (25.7%). The seroprevalence of HIV/HBV coinfection was of 6.3%. The results showed that the seroprevalence of HBV was similar in most municipalities: 25.8% in Belas; 26.6% in Viana; 27.6% in Luanda; 19.2% in Cacuaco; and 15.6% Cazenga. For HIV, the seroprevalence was also close ranges among the municipalities: 10.0% in Belas; 14.5% in Viana 14.9% in Luanda and 12.5% in Cazenga. However, the seroprevalence in municipality of in Cacuaco was lower (5.8%) and bivariate and multivariate analysis showed a lower risk for HIV in this area (OR 0.348, CI 0.083–0.986; OR 0.359, CI 0.085–1.021). The multivariate analysis had also showed a significant increased risk for HIV in women with 2 or 3 births (OR 1.860, CI 1.054–3.372).ConclusionsOur results underlined the need to improve the screening and clinical follow-up of HIV and HBV in Angola, as well the educational campaigns to prevent not only the morbidity and mortality associated with these diseases, but also their transmission, mainly in women in reproductive age and pregnant, encouraging the pre-natal consultations in order to avoid mother-to-child transmission.

Prevalence and Determinants of Vitamin D Deficiency in 9595 Mongolian Schoolchildren: A Cross-Sectional Study.

Population-based data relating to vitamin D status of children in Northeast Asia are lacking. We conducted a cross-sectional study to determine the prevalence and determinants of vitamin D deficiency in 9595 schoolchildren aged 6–13 years in Ulaanbaatar (UB), the capital city of Mongolia. Risk factors for vitamin D deficiency were collected by questionnaire, and serum 25-hydroxyvitamin D (25[OH]D) concentrations were measured using an enzyme-linked fluorescent assay, standardized and categorized as deficient (25[OH]D <10 ng/mL) or not. Odds ratios for associations between independent variables and risk of vitamin D deficiency were calculated using multivariate analysis with adjustment for potential confounders. The prevalence of vitamins D deficiency was 40.6% (95% CI 39.7% to 41.6%). It was independently associated with female gender (adjusted odds ratio [aOR] for girls vs. boys 1.23, 95% CI 1.11–1.35), month of sampling (aORs for December–February vs. June–November 5.28 [4.53–6.15], March–May vs. June–November 14.85 [12.46–17.74]), lower levels of parental education (P for trend <0.001), lower frequency of egg consumption (P for trend <0.001), active tuberculosis (aOR 1.40 [1.03–1.94]), household smoking (aOR 1.13 [1.02 to1.25]), and shorter time outdoors (P for trend <0.001). We report a very high prevalence of vitamin D deficiency among Mongolian schoolchildren, which requires addressing as a public health priority.

Programmed Cell Death Protein 1-overexpressed CD8+ T Lymphocytes Play a Role in Increasing Chronic Hepatitis B Disease Progression

BACKGROUND: T lymphocyte activation depends on the balance of co-stimulatory and co-inhibitory signals determined by Cluster of Diffrentiation (CD)28 and Programmed Cell Death Protein 1 (PD-1) expression. Alteration in CD28 and PD-1 expression might affect the progression of chronic hepatitis B (CHB). Current study was conducted to evaluate the correlations of the CD28 and PD-1 expressions of T lymphocytes and CHB progression.METHODS: Subjects were recruited, selected and divided into 3 groups, inactive CHB, active CHB and CHB with End-Stage Liver Disease (ESLD). HBeAg was determined by using Enzyme-Linked Fluorescence Assay while HBV-DNA was carried out by the RT-PCR method. Numbers of T lymphocytes expressing CD3, CD4, CD8, CD45, CD28 and PD-1 molecules were determined by flowcytometry. RESULTS: There was no significant difference in the expression of CD28 by CD4+ and CD8+ T lymphocytes of inactive CHB, active CHB and CHB with ESLD subjects. There was also no significant difference in the expression of PD-1 in CD4+ lymphocytes of inactive CHB, active CHB and ESLD subjects. In contrast there was a significant increase in the expression of PD-1 in CD8+ T lymphocytes of ESLD subjects.CONCLUSION: CD28 expression among CHB subjects was within normal range and not related to disease progression, but PD-1 expression of CD8+ T lymphocyte was increased along with disease progression, especially in CHB subjects with ESLD. This suggests that PD-1-overexpressed CD8+ T lymphocyte play a role in increasing CHB disease progression.KEYWORDS: chronic hepatitis B, CD28, PD-1, T lymphocyte, disease progression

Association between Suicide and Toxoplasma gondii Seropositivity.

This study aimed to determine the association between suicide and Toxoplasma gondii (T. gondii) seropositivity. Serum samples of 89 decedents who committed suicide (cases) and 58 decedents who did not commit suicide (controls) were tested for anti-T. gondii IgG and IgM antibodies using enzyme-linked immunosorbent assays. Anti-T. gondii IgM antibodies were further detected by enzyme-linked fluorescence assay (ELFA). A total of 8 (9.0%) of the 89 cases and 6 (10.3%) of the 58 controls were positive for anti-T. gondii IgG antibodies (OR: 0.85; 95% CI: 0.28–2.60; p = 0.78). Anti-T. gondii IgG levels were higher than 150 IU/mL in two (2.2%) cases and in five (8.6%) controls (OR: 0.24; 95% CI: 0.04–1.30; p = 0.11). Anti-T. gondii IgM antibodies were not found in any case or control using the enzyme immunoassay and were found in only one (1.7%) control using ELFA (p = 0.39). Rates of IgG seropositivity and high levels of anti-T. gondii antibodies were similar in cases and in controls regardless of their sex or age groups. The results do not support an association between T. gondii seropositivity and suicide. However, the statistical power of the test was low. Further research is necessary to confirm this lack of association.

Changes in serum levels of CEA and CA19-9 tumor markers in different stages of patients with colorectal cancer

Background: Colorectal cancer is one of the most common gastrointestinal cancers worldwide with a high prevalence among middle-aged people. This study aimed to evaluate and compare changes in serum levels of carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9), as two important tumor markers, in the diagnosis of different stages of colorectal cancer. Materials and Methods: This basic research was conducted on hospitalized patients with colorectal cancer (n=67). At first, tissue samples and venous blood samples were collected from patients. Subsequently, CEA and CA19-9 tumor markers were measured by enzyme-linked fluorescence assay and cellular changes were investigated by hematoxylin and eosin staining. Results: In this study, 57.6% and 43.3% of the patients were male and female, of which 59.7% (40 patients) cases were over 61 years old. The most common sites of tissue involvement were found to be the rectum and sigmoid. In the acute phase of the disease, a decrease was observed in the number of red blood cells (P=0.0091) and the level of hemoglobin (P=0.141); however, the number of platelets remained unchanged (P=0.212). In addition, lymphocyte and neutrophil counts increased at first, while they decreased later. The findings showed that there was a significant relationship between these two tumor markers and disease levels. Conclusion: Our results indicated that although these tumor markers are not suitable factors for the diagnosis of this cancer in the early stages, they can be used as two important markers to diagnose the progression of the disease.

Assessment of serum vitamin D level and seminal vitamin D receptor gene methylation in a sample of Egyptian men with idiopathic infertility

Vitamin D deficiency has been linked with different health problems including male infertility. Its function is mediated by the vitamin D receptor, which acts as a transcription factor. Epigenetic mechanisms such as DNA methylation may affect the vitamin D receptor gene and result in gene silencing. The present study aimed to assess serum vitamin D level and seminal methylation of vitamin D receptor gene in idiopathic male infertility. Blood and semen samples were collected from 60 men with idiopathic infertility and 40 healthy fertile men. Vitamin D levels were detected using enzyme-linked fluorescent assay technique and methylation status was assessed by methylation-specific PCR. Results revealed that serum levels of 25OHD were significantly lower in patients compared to controls. Positive correlation was found between serum level of 25OHD and sperm concentration in patients group and progressive motility in total studied group. Methylation of vitamin D receptor gene was significantly higher in patients compared to control group. Negative correlation was found between methylation of vitamin D receptor gene and both sperm concentration and progressive motility in total studied group. Results of the present study suggest that vitamin D deficiency and vitamin D receptor gene methylation may be involved in aetiopathogenesis of idiopathic male infertility.

Association of CYP27B1 Polymorphism and Vitamin D Levels with Multiple Sclerosis Development in Lebanese Population of Bekaa Region: A Preliminary Study

Multiple sclerosis (MS) is a neurodegenerative disease of the central nervous system (CNS). Interaction between genetic and environmental factors guides the development of the disease. Among environmental factors, vitamin D deficiency is shown to increase the risk of MS development. Several single nucleotide polymorphisms (SNPs) in cytochrome P450 family 27 subfamily B (CYP27B1) gene that encodes the rate-limiting enzyme involved in vitamin D metabolism, were shown to be correlated with MS. We aimed at investigating the association of CYP27B1 gene polymorphisms and vitamin D level with MS development in a sample of Lebanese MS patients living in the Bekaa region. Enrolled MS patients and controls were age and gender matched. Genotyping was performed by sequencing the amplified CYP27B1 PCR products. Vitamin D levels were measured using a VIDAS® 25 OH Vitamin D total assay based on enzyme linked fluorescent assay (ELFA). Chi-square and Mann-Whitney U tests were used for statistical analysis. A significant association was shown between vitamin D deficiency and MS without any association between CYP27B1 studied SNPs and the disease. We confirmed that vitamin D deficiency was associated with MS with no implication of the studied SNPs of CYP27B1 gene with disease susceptibility among the Lebanese MS patients living in the Bekaa region.

STUDY OF TOXIN PRODUCTION IN PATIENTS WITH CLOSTRIDIUM DIFFICILE ASSOCIATED DIARRHOEA

Introduction: Clostridium difcile infection (CDI) is dened as the presence of diarrheal symptoms and either a stool test result positive for C. difcile toxins or detection of toxigenic C. difcile, or colonoscopic ndings demonstrating pseudomembranous colitis. C.difcile produces toxin A (enterotoxin) and B (cytotoxin), under favorable conditions. Both toxins severely affect GIT. The relationship between the amount of toxins in the feces and the severity of symptoms has been found. Aim &amp; Objectives : To detect C.difcile toxin production in stool samples with laboratory conrmed CDI and to correlate the presence of toxin with disease severity Material &amp; Methods: A prospective laboratory based study done in a tertiary care Medical college and allied hospitals in Gwalior (MP) in a duration of 11 months, which included stool samples of 118 patients with laboratory conrmed CDI. Toxin levels in stool samples were detected and correlated with the clinical condition. Toxin A &amp; B study were performed on stool sample with ELFA (Enzyme Linked Fluorescent Assay) technology (VIDAS instruments). Results and Discussion: 118 patients with laboratory conrmed CDI. Toxin levels in stool samples were detected in 08 patients. The toxin positivity rate was 6.79%. All of these hospitalized patients had severe diarrhea and history of administration of broad spectrum antibiotics Conclusion: Signicant toxin load in the fecal samples may be associated with the signicant deterioration of the general condition of the patient.

Detection and Virulence Characterization of Listeria monocytogenes Strains in Ready-to-Eat Products

The public health risk posed by Listeria monocytogenes in ready-to-eat (RTE) foods depends on the effectiveness of its control at every stage of the production process and the strain involved. Analytical methods currently in use are limited to the identification/quantification of L. monocytogenes at the species level, without distinguishing virulent from hypovirulent strains. In these products, according to EU Regulation 2073/2005, L. monocytogenes is a mandatory criterion irrespective of strain virulence level. Indeed, this species encompasses a diversity of strains with various pathogenic potential, reflecting genetic heterogeneity of the species itself. Thus, the detection of specific L. monocytogenes virulence genes can be considered an important target in laboratory food analysis to assign different risk levels to foods contaminated by strains carrying different genes. In 2015-2016, a severe invasive listeriosis outbreak occurred in central Italy, leading to the intensification of routine surveillance and strain characterization for virulence genetic markers. A new multiplex real-time polymerase chain reaction targeting main virulence genes has been developed and validated against the enzyme-linked fluorescent assay (ELFA) culture-based method. Results of the improved surveillance program are now reported in this study.

Serological identification of past and recent SARS-CoV-2 infection through antibody screening in Luanda, Angola.

Serological identification of past and recent SARS-CoV-2 infection through antibody screening in Luanda, Angola.

Von Willebrand factor in follicular fluid in women undergoing IVF/ICSI: a “ghost” associated with oocyte and embryo quality

Introduction: The purpose of the present study to determine the presence of Von Willebrand factor (vWF) in the follicular fluid of women undergoing IVF/ICSI and to investigate the association of its concentration with oocyte and embryo quality. Methods: We conducted a prospective observational study based in women undergoing in vitro fertilization treatment. vWF concentrations in follicular fluid samples collected during transvaginal oocyte retrieval were measured using an enzyme-linked immunosorbent assay (Elisa). They were also analyzed by the VIDAS® vWF method for confirmation of the results. The latter is an automated quantitative test for the measurement of vWF in human plasma, using the ELFA technique (enzyme-linked fluorescent assay). vWF concentrations were correlated to oocyte and embryo quality. Results: Contrary to previous reports, vWF was determined in follicular fluid. A higher percentage of good quality oocytes were found in the presence of lower vWF follicular fluid levels. Similarly, better quality embryos were derived from oocytes retrieved from follicles with lower vWF follicular fluid levels. Conclusions: Contrary to existing evidence to date, vWF was found in the follicular fluid of women undergoing IVF/ICSI treatment. In addition, the quality of oocytes and embryos was adversely related to vWF follicular fluid levels. In fact, a better outcome of IVF/ICSI treatment was suggested when the levels of vWF in follicular fluid were low. In this context, vWF follicular fluid levels could be used as a prognostic factor for oocyte and embryo quality.

L-GLUTAMINE IMPROVES ADIPOSE FUNCTION AND AMELIORATES EXCESS HEPATIC LIPID IN ESTROGEN-PROGESTIN ORAL CONTRACEPTIVE-TREATED FEMALE RATS

Objective: Adipose dysfunction and inflammation with or without hepatic defects underlie metabolic obesity. Glutamine (GLU) improves glucoregulation and metabolic indices but its effects on adipose function and hepatic lipid deposition in estrogen-progestin oral contraceptive (EPOC) users are unknown. We therefore hypothesized that GLUT supplementation would protect against adipose dysfunction and excess hepatic lipid influx and deposition in animals treated with EPOC by suppressing adenosine deaminase (ADA) activity and improving glucose-6-phosphate dehydrogenase (G6PD)-dependent antioxidant defense. Design and method: Female Wistar rats weighing between 150–180 g were allotted into control, GLUT, EPOC and EPOC + GLUT groups (six rats per group). The groups received vehicle (distilled water, p.o.), GLUT (1 g/kg), EPOC containing 1.0 μg ethinylestradiol plus 5.0 μg levonorgestrel and EPOC plus GLUT respectively, daily for 8 weeks. Glucoregulatory parameters were determined by homeostatic model of assessment (HOMA-IR) and quantitative insulin sensitivity check index (QUICKI), while metabolically-induced obesity was determined using triglyceride-glucose index. Plasma and tissue biochemical analysis were estimated with enzyme-linked immunosorbent assay kits or fluorescence assay as appropriate Results: Results showed that the administration of EPOC caused glucose dysregulation and increased triglyceride-glucose index and visceral adiposity, but the body weight and liver weight were not affected. However, EPOC significantly decreased adipose lipid, G6PD and glutathione, and increased glycogen synthesis, ADA, XO, uric acid, lipid peroxidation, lactate production and Gamma-glutamyl transferase activity (GGT). On the other hand, EPOC significantly increased hepatic lipid, ADA, XO, uric acid, lipid peroxidation and lactate production, and decreased glycogen synthesis, G6PD and glutathione. Nevertheless, supplementation with glutamine attenuated these alterations. Conclusions: Collectively, the present results indicate that EPOC causes metabolically-induced obesity which is associated with adipose dysfunction and hepatic metabolic defection. The findings also suggest that glutamine confers metabo-protection with corresponding improvement in adipose and hepatic metabolic function by suppression of ADA activity and enhancement of G6PD-dependent antioxidant defense (Figure 1).