The Impact of Silver Nanoparticles Produced by Bacillus pumilus As Antimicrobial and Nematicide.

This study evaluates the potential application of silver nanoparticles (AgNPs) as antimicrobial or nematicidal agents produced by the extremophile Bacillus pumilus, which was isolated from the alkaline Wadi El-Natrun Lake in Egypt. The AgNPs were characterized by ultraviolet-visible absorption spectroscopy, transmission electron microscopy, and energy dispersive x-ray spectroscopy. The size of AgNPs formed ranged from 20.12 to 29.48 nm. Panagrellus redivivus was exposed to different concentrations (0, 50, 100, 150, and 200 µg/mL) of AgNPs in a 5 mL nematode suspension (1 × 103 mL-1). The best result occurred at AgNP concentrations of 150 and 200 µg/mL, with death rates of 80 and 91%, respectively, following 48 h of exposure. AgNPs also exhibited potent antimicrobial properties when using Gram-negative and Gram-positive human pathogens, with MIC and MBC values of 5 and 10 µg/mL, respectively. These laboratory assays prove that biologically synthesized AgNPs are an ecofriendly material that can be used in lieu of solvents or toxic chemicals.

Methylenetetrahydrofolate reductase gene polymorphisms in Egyptian Turner Syndrome patients.

BACKGROUND: Folate metabolism dysfunctions can result in DNA hypomethylation and abnormal chromosome segregation. Two common polymorphisms of the methylenetetrahydrofolate reductase (MTHFR) encoding gene (C677T and A1298C) reduce MTHFR activity, but when associated with aneuploidy, the results are conflicting. Turner Syndrome (TS) is an interesting model for investigating the association between MTHFR gene polymorphisms and nondisjunction because of the high frequency of chromosomal mosaicism in this syndrome. OBJECTIVE: To investigate the association of MTHFR gene C677T and A1298C polymorphisms in TS patients and their mothers and to correlate these polymorphisms with maternal risk of TS offspring. SUBJECTS AND METHODS: MTHFR C677T and A1298C polymorphisms were genotyped in 33 TS patients, their mothers and 15 healthy females with their mothers as controls using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and sequencing technique. RESULTS: Genotype and allele frequencies of both C677T and A1298C were not significantly different between TS cases and controls. There were no significant differences in C677T genotype distribution between the TS mothers and controls (p=1). The MTHFR 1298AA and 1298AC genotypes were significantly increased in TS mothers Vs. control mothers (p=0.002). The C allele frequency of the A1298C polymorphism was significantly different between the TS mothers and controls (p=0.02). The association of A1298C gene polymorphism in TS patients was found to increase with increasing age of both mothers (p=0.026) and fathers (p=0.044) of TS cases. CONCLUSION: Our findings suggest a strong association between maternal MTHFR A1298C and risk of TS in Egypt.

DNA barcode through cytochrome b gene information of mtDNA in native chicken strains.

This study was carried out to figure out the potentiality of a cytochrome b gene as a barcoding tool in discriminating native chicken strains and other Gallus gallus species. We performed PCR amplification using universal primer to amplify around 415 bp fragment of cytochrome b gene of mtDNA. The results revealed that all Saudi chicken strains were identical to each other but when compared with other species of Gallus the differences were exciting. The phylogenetic tree revealed that there were seven clusters represented for native strains and were clustered together especially in black strain and dark brown ones. The results have confirmed that using cytochrome b gene to discriminate between Saudi chicken strains and other species of G. gallus fowl was a very sufficient tool. Moreover, we can consider short fragment of cytochrome b gene of mtDNA as a universal DNA barcode region. It was a much more accurate and efficient tool to discriminate interspecies than intraspecies. We think it needs more studies to confirm this concept, and we have to apply that tool for many species of vertebrate and invertebrate as well.

Growth curves of Egyptian patients with Turner syndrome.

This study analyzes the body anthropometric measurements in females with Turner syndrome (TS) not treated with recombinant human growth hormone. Height, weight, head circumference, and body mass index (BMI) data were collected from 93 patients. Their ages ranged from 6 months to 24 years (mean 10 ± 4.3 years). Chromosomal analysis revealed: 55 patients with 45,X and 38 patients with mosaic karyotypes. Patients were divided into yearly age groups. Standard growth curves were constructed for these Egyptian Turner syndrome (TS) patients. Mean and standard deviations were estimated across the age groups. When comparing the mean heights of patients to the Egyptian standards, short stature (≤2 SD) was found in 96.8% of patients older than 6 years. Patients' mean weight and BMI were higher than controls. The mean height of the studied Egyptian patients was slightly lower than that of females with TS in UK and European patients. Therefore, local reference values are more appropriate than International standards. The charts presented here can be used to optimize routine healthcare for Egyptian TS patients. The use of growth charts specific for Egyptian TS patients can help to discover early physical developmental delay and suggests the necessity of looking for concomitant diseases affecting growth.

Phenotypic characterization of rare interstitial deletion of chromosome 4.

Interstitial deletion of the long arm of chromosome 4 is rare. Patients with interstitial deletion of the long arm of chromosome 4 differ from those with terminal deletions. Phenotypes may be variable, depending upon the specific length and location of the deleted portion. Here, we report on a boy exhibiting most of the congenital malformations encountered in terminal 4q syndrome. The conventional karyotyping and Fluorescence in-situ hybridization revealed a de novo interstitial del (4)(q31q32). The current report is a further document highlighting that deletion of segment q31 could be contributing to the expression of most of the phenotype of 4q deletion syndrome. Using array comparative genome hybridization methodology is recommended for investigating further cases with similar segmental interstitial deletions to support and delineate findings and to define genes implicated in the pathogenesis of the disorder.