Maternal Exposure to Cadmium and Fetal Growth: a Systematic Review and Meta-Analysis

Biological Trace Element Research - This study aims to review the epidemiological studies on the association between cadmium (Cd) exposure during pregnancy and neonatal anthropometric measures....     

Evaluation of a new antigen for diagnosis of Helicobacter pylori infection in stool of adult and children

Background: Nowadays, there is an increasing interest in noninvasive methods to diagnose Helicobacter pylori infection. Indeed, they can profitably replace endoscopy in predicting the diagnosis. The stool antigen test for H. pylori is a noninvasive immunoassay to diagnose active infection with this bacterium in human fecal samples. The aim of this study was detection of alkyl hydroperoxide reductase protein (AhpC) antigen by immunoblotting in stool samples for diagnosis of H. pylori. Materials and Methods: Chromosomal DNA from H. pylori was isolated. AhpC gene was amplified by PCR, These amplicons were cloned into pTZ57R/T cloning vector then subcloned into pQE30 expression vector and overexpressed using isopropyl‐beta‐D‐thiogalactopyranoside in E. coli M15. AhpC protein was purified by affinity chromatography. Rabbits were immunized with the purified AhpC protein for the production of antibodies. To determine the accuracy of the test for diagnosing H. pylori infection from stool, we evaluated 84 patients (6–81 years old) using Western blot analysis by rabbit anti‐AhpC antibody. Positive rapid urease test on biopsy samples was considered as the gold standard. Results: AhpC gene was overexpressed, and AhpC protein was purified. Rabbit anti‐AhpC antibody produced after immunization with the purified AhpC protein. By immunoblotting, we detected AhpC protein in the positive stool samples. The test showed a 83.3% sensitivity (95% CI: 69.8–92.5%) and a 91.7% specificity (95% CI: 77.5–98.2). Among the children, the sensitivity was 88.2% (95% CI: 63.6–98.5) and the specificity was 100% (95% CI: 69.2–100); in adults, the sensitivity and specificity were 80.6% (95% CI: 62.5–92.5) and 88.5% (95% CI: 69.8–97.6), respectively. Conclusions: Using of AhpC antigen for diagnosis of H. pylori infection is a useful noninvasive method, accurate in adolescents and children, and can be used for the development of a stool antigen detection kit for H. pylori.     

Biofilm and Siderophore Effects on Secondary Waste Water Disinfection

The efficiency of ultraviolet (UV) light disinfection of wastewater effluent using a large-scale pilot system was studied. The relationship between biofilm and siderophore production and UV doses received by Pseudomonas aeruginosa strain ATCC 15442 was determined. UV decreased pyoverdine production and enhanced biofilm production. Consequently external factors conditioned by both pyoverdine and biofilm may affect the UV effect on bacterial disinfection.     

Analyse du statut oxydatif spermatique chez des patients infertiles

Introduction

Male infertility constitutes public health problems. Several factors are at the origin of this phenomenon. Currently, the oxidative stress is accused to be one of the leading causes. In our study, we sought a correlation between the markers of the oxidative stress and the sperm characteristics (morphology).

Material and methods

We evaluated the antioxidant status in the seminal plasma of 129 infertile men. Patients were characterized by infertility of variable duration. They were divided into four groups: normozoospermics who were considered as controls (n=34), asthenozoospermics (Astheno; n=43), oligozoospermics (Oligo; n=22) and teratozoospermics (Terato; n=30). Among the oxidative stress markers, we evaluated, in seminal plasma, zinc, calcium, magnesium and selenium by spectrophotometry of atomic absorption to flame and furnace. The malondialdehyde (MDA) is proportioned by spectrofluorometry.

Results

Our results show that the seminal concentrations of zinc and selenium are higher in the control group than the concentrations of these same elements in the three other groups. The seminal zinc concentration was significantly correlated with the sperm count (r=0.49; p < 0.001) and MDA (r=- 0.35; p<0.05). Sperm motility was correlated with calcium (r=0.41; p<0.001) and magnesium (r=0.31; p<0.05). The MDA concentration is higher in the three groups of patients: oligozoospermics (3.22±1.37 ??g/ml), asthenozoospermics (3.52±1.93 ??g/ml) and teratozoospermics (3.64±1.73 ??g/ml) compared with controls (2.32±0.94 ??g/ml). A single positive correlation was observed between the MDA and morphology (r=0.19; p<0.05).

Conclusion

Our study confirms that the oxidative stress plays an important role in the process of deteriorations of the spermatozoa. The free radicals can, indeed, modify the membrane structure as well as the membrane structure of the deoxyribonucleic acid. These deteriorations also lead to an increase in the percentage of sperm of abnormal forms.     

Culture of Helicobacter pylori from stool samples in children

We evaluated two protocols for isolation of Helicobacter pylori in stool from biopsied and nonbiopsied children. Twenty-three child patients whose presumptive positivity or negativity was diagnosed by endoscopy and a rapid urease test at site were used to compare biopsy-based tests with stool-based tests (H. pylori stool antigen test and stool culture). Their gastric activity and bacterial density were graded by the updated Sydney system. Biopsy and stool specimens were cultured on Campy-blood and Belo horizonte agar plates after enrichment in selective Campy-Thio medium. To compare two stool culture protocols, stools from 20 nonbiopsied children were tested by the HpSA test and cultured either as above or after treatment with cholestyramine. Grown colonies were screened by Gram staining, slide agglutination using anti-H. pylori monoclonal IgG; positive isolates were tested by biochemical tests and polymerase chain reaction for H. pylori-specific ureA gene. Coccoid H. pylori was isolated in stool samples from the biopsied patients whose bacterial density was two to four in histology. Their oxidase was slightly positive but became positive after two subcultures, while additional biochemical tests confirmed the isolation of H. pylori. Similar coccoid but oxidase positive H. pylori was isolated from three nonbiopsied children with the protocol of cholestyramine treatment only. The density of bacteria in the stomach may influence the recovery of H. pylori from stool; inactivation of bile with cholestyramine improves the yield in culture and favors isolation of an enhanced metabolic form of bacteria.     

Effects of Selenium Supplementation on Gene Expression Levels of Inflammatory Cytokines and Vascular Endothelial Growth Factor in Patients with Gestational Diabetes

Selenium is known to exert multiple beneficial effects including anti-inflammatory actions. The aim of the study was to evaluate the effects of selenium supplementation on gene expression levels of inflammatory cytokines and vascular endothelial growth factor (VEGF) in women with gestational diabetes (GDM). This randomized double-blind, placebo-controlled trial was carried out among 40 subjects diagnosed with GDM aged 18–40 years old. Subjects were randomly allocated into two groups to receive either 200 μg/day selenium supplements (n = 20) or placebo (n = 20) for 6 weeks. Gene expression of inflammatory cytokines and VEGF were assessed in lymphocytes of GDM women with RT-PCR method. Results of RT-PCR indicated that after the 6-week intervention, compared with the placebo, selenium supplementation downregulated gene expression of tumor necrosis factor alpha (TNF-α) (P = 0.02) and transforming growth factor beta (TGF-β) (P = 0.01), and upregulated gene expression of VEGF (P = 0.03) in lymphocytes of patients with GDM. There was no statistically significant change following supplementation with selenium on gene expression of interleukin (IL)-1β and IL-8 in lymphocytes of subjects with GDM. Selenium supplementation for 6 weeks in women with GDM significantly decreased gene expression of TNF-α and TGF-β, and significantly increased gene expression of VEGF, but did not affect gene expression of IL-1β and IL-8. Clinical trial registration number http://www.irct.ir: IRCT201612045623N95.     

Characterization of the Humoral Immune Response during Staphylococcus aureus Bacteremia and Global Gene Expression by Staphylococcus aureus in Human Blood

Attempts to develop an efficient anti-staphylococcal vaccine in humans have so far been unsuccessful. Therefore, more knowledge of the antigens that are expressed by Staphylococcus aureus in human blood and induce an immune response in patients is required. In this study we further characterize the serial levels of IgG and IgA antibodies against 56 staphylococcal antigens in multiple serum samples of 21 patients with a S. aureus bacteremia, compare peak IgG levels between patients and 30 non-infected controls, and analyze the expression of 3626 genes by two genetically distinct isolates in human blood. The serum antibody levels were measured using a bead-based flow cytometry technique (xMAP®, Luminex corporation). Gene expression levels were analyzed using a microarray (BµG@s microarray). The initial levels and time taken to reach peak IgG and IgA antibody levels were heterogeneous in bacteremia patients. The antigen SA0688 was associated with the highest median initial-to-peak antibody fold-increase for IgG (5.05-fold) and the second highest increase for IgA (2.07-fold). Peak IgG levels against 27 antigens, including the antigen SA0688, were significantly elevated in bacteremia patients versus controls (P≤0.05). Expression of diverse genes, including SA0688, was ubiquitously high in both isolates at all time points during incubation in blood. However, only a limited number of genes were specifically up- or downregulated in both isolates when cultured in blood, compared to the start of incubation in blood or during incubation in BHI broth. In conclusion, most staphylococcal antigens tested in this study, including many known virulence factors, do not induce uniform increases in the antibody levels in bacteremia patients. In addition, the expression of these antigens by S. aureus is not significantly altered by incubation in human blood over time. One immunogenic and ubiquitously expressed antigen is the putative iron-regulated ABC transporter SA0688.     

Antiproliferative activity of morpholine-based compounds on MCF-7 breast cancer,colon carcinoma C26, and normal fibroblast NIH-3T3 cell lines and study of their binding affinity to calf thymus-DNA and bovine serum albumin

Abstract

This report describes the results of a study on the antiproliferative activity of the morpholine-based ligand 1,3-bis(1-morpholinothiocarbonyl)benzene (HL) and its nickel(II) complex (NiL) against human breast cancer cells (MCF-7), colon carcinoma cells (C26), and normal fibroblast NIH-3T3 cells. NiL showed better cytotoxicity on both cancerous cells relative to normal cells in vitro with the highest selective index of 2.22 in MCF-7 cells. The interaction of both compounds with calf thymus DNA (CT DNA) and bovine serum albumin (BSA) was studied using various spectroscopic techniques and analytical methods such as UV???vis titrations, thermal denaturation, circular dichroism, competitive fluorescent intercalator displacement assays, as well as molecular modeling. The fluorescence intensity of the probe molecule increases clearly when HL and NiL are added to the methylene blue (MB)–DNA system. Furthermore, the binding of HL and NiL quenches the BSA fluorescence, revealing a 1:1 interaction with a binding constant of about 10⁵?M^?1.

Communicated by Ramaswamy H. Sarma