1,2,4-Triazine Chemistry Part II: Synthetic approaches for phosphorus containing 1,2,4-triazine derivatives

This review represents the methods developed for the synthesis of phosphorus containing 1,2,4-triazine moieties. These methods depends on the phosphorylation of side functional groups of 1,2,4-triazines and cyclization of side functional groups of 1,2,4-triazines with phosphorus reagents to give isolated and fused phosphorus heterocyclic systems

Effects of dietary baker’s yeast extract on the growth, blood indices and histology of Nile tilapia ( Oreochromis niloticus L.) fingerlings

Nile tilapia, Oreochromis niloticus (average initial weight, 5.91 ± 0.04 g), were fed four isonitrogenous and isolipidic diets for 84 days. The diets contained four levels of yeast extract (CW‐I) rich in nucleotides and β‐glucan: 0 (control), 5, 10 and 15 g/kg diet. Weight gain increased linearly, whereas the feed conversion ratio decreased linearly with increasing levels of yeast extract. The diet containing 15 g/kg yeast extract resulted in significantly better (p 0.05) differences were found in dry matter, protein, lipid or ash contents or in haematocrit, haemoglobin or total protein contents among the treatment groups. Blood sample profiles showed an increase in white and red blood cells in fish fed 15 g/kg yeast extract in comparison with the other treatment groups. The fish fed the diets with 10 and 15 g/kg yeast extract had significantly higher albumin and globulin levels than the control group, whereas decreased levels of cholesterol and triglycerides, aspartate aminotransferase and alanine aminotransferase were noted in fish fed the diet with 15 g/kg yeast extract. Histological analysis of the liver and intestine in fish fed the control diet showed a slightly abnormal structure in these organs. Only in fish fed diets supplemented with the highest amount of yeast extract was the structure of the hepatocytes and villi almost unchanged, which indicated that the yeast nucleotides could improve hepatic function and promote liver and gut restoration

Multidrug resistance and extended-spectrum β-lactamases genes among0 Escherichia coli from patients with urinary tract infections in Northwestern Libya

Introduction: Multidrug resistance (MDR) and emergence of extended-spectrum β-lactamases (ESBLs) that mediate resistance to b-lactam drugs among Escherichia coli and other uropathogens have been reported worldwide. However, there is little information on the detection of ESBLs genes in E. coli from patients with urinary tract infections (UTIs) in the Arab countries using polymerase chain reaction (PCR), and in Libya such information is lacking.Methods: All patients attending Zawiya Teaching Hospital in Zawiya city between November 2012 and June 2013 suspected of having UTIs and from whom midstream urine samples were taken as part of the clinical workup were included in this prospective study. Samples were examined for uropathogens by standard bacteriological procedures. VITEK-2 automated microbiology system was used to identify the isolated uropathogens and determine the susceptibility of E. coli and Klebsiella spp. isolates to antimicrobials. In addition, phenotypically ESBLs-positive E. coli isolates were tested for ESBLs genes by PCR.Results: The present study enrolled 1,790 patients with UTIs. Uropathogens were found in 371 (20.7%) urine specimens examined. Mixed pathogens were detected in two specimens with 373 total pathogens isolated. E. coli and Klebsiella spp. were the predominant uropathogens at 55.8% (208/373) and 18.5% (69/373), respectively. Other pathogens were detected in 25.7% (96/373) of urine samples. Of the E. coli and Klebsiella spp. tested, 69.2 and 100% were resistant to ampicillin, 6.7 and 33.3% to ceftriaxone, and 23.1 and 17.4% to ciprofloxacin, respectively. MDR (resistance to ]3 antimicrobial groups) was found in 69 (33.2%) of E. coli and in 29 (42%) of Klebsiella spp. isolates. ESBLs were detected phenotypically in 14 (6.7%) of E. coli and in 15 (21.7%) of Klebsiella spp. isolates. Thirteen out of the 14 phenotypically ESBL-positive E. coli were positive for ESBL genes by PCR. blaTEM gene was detected in seven isolates, blaOXA gene in 10 isolates and blaCTX-M gene in six isolates. blaSHV gene was not detected in the present study.Conclusion: The isolation of MDRESBL-producing uropathogens undoubtedly will limit the choices clinicians have to treat their patients with UTIs. Therefore, there is an urgent need for surveillance studies on antimicrobial resistance and prevalence of ESBLs among uropathogens to guide the clinical treatment of UTIs in Libya in the future.Keywords: urinary tract infections; Escherichia coli; extended-spectrum β-lactamases; multidrug resistance; Liby

1,2,4-Triazine Chemistry Part I: Orientation of cyclization reactions of functionalized 1,2,4-triazine derivatives

Orientation of heterocyclization reactions of functionalized 1,2,4-triazines were studied by effect of substituents in 1,2,4-triazine moieties, type of the solvent used in the reaction and the temperature effect. Also, it was found that cyclization process depended mainly on the chemoselective and regioselectivity states of the parent substrate as well as preferring cite of ring closure

Thiazolidinone Steroids Impregnated Polyurethane Foams as a Solid Phase Extractant for the Extraction and Preconcentration of Cadmium(II) from Industrial Wastewater

Abstract: Two new thiazolidinone steroids namely sulfadiazino-imino-steroid (I) and 3-sulfonamoyl-phenyl-spiro[4-oxo-thiazolidin-2, 2`steroid] (II) were prepared and characterized from their molecular weight determination and spectroscopic measurements. Compound II were physically immobilized onto polyurethane foams (PUFs) for the preconcentration of cadmium(II) from acidic aqueous media containing iodide ions. The kinetics of the retention step of cadmium(II) from aqueous solutions by compound II treated PUFs was studied. Particle diffusion was the most probable operating mechanism and did not control the kinetics of cadmium(II) retention by compound II immobilized PUFs. A preconcentration / separation procedure is presented for the solid phase extraction of trace cadmium(II) from aqueous media as its ternary complex ion associate with compound II in industrial wastewater samples onto compound II treated PUFs prior to determination by flame atomic absorption spectrometry (FAAS). Compound II treated PUFs sorbent was successfully packed in glass column for complete extraction and / or determination of trace concentrations of cadmium(II) in wastewater samples with satisfactory recovery (95 ±2.6). The cyclic voltammetry of compound II showed two well defined irreversible redox couples and suggested its possible use as complexing agent in stripping voltammetric determination of trace concentrations of toxic metal ions in wastewater

Human Norovirus prevalence in Africa:a review of studies from 1990 to 2013

OBJECTIVES: To assess the contribution of Human Norovirus to diarrheal diseases in Africa.   METHODS: We conducted a systematic review of the PubMed and EMBASE databases for published articles of Human Norovirus in Africa between 1990 and 2013. Data were extracted from selected studies and analysed.   RESULTS: A total of 208 eligible studies were identified, of which 55 (from 19 countries) met the inclusion criteria. Many cases were of sporadic gastroenteritis (70.9%) in children (82%), 65.4% of which were seen in an outpatient setting. Over half (59.4%) of affected children were under 5 years of age. The pooled prevalence rate of Human NoV was 11% (95% CI 8-14%) and the meta-analysis indicated significant heterogeneity between the studies. However, the conditional negative binomial regression could not clearly find the factors affecting the Human NoV prevalence rates reported. A close relationship was found between Human Norovirus strains from environmental and clinical samples.   CONCLUSION: Unreported sporadic gastroenteritis cases of Human Norovirus are common in Africa. Most are community-associated infections. Possible environmental transmission routes have been documented. Combined environmental and clinical studies are required for targeted actions to control transmission of Human Norovirus in Africa. Systematic surveillance of Human Norovirus is needed to measure the burden of Norovirus-induced gastroenteritis in Africa and support any requirements for vaccine development. This article is protected by copyright. All rights reserved

Facile Development, Characterization, and Optimization of New Nano-Demulsifiers System for Treating Water in-Crude Oil Emulsions

A novel series of new nano-demulsifiers based on a polymerizable nonionic surfactant for treating water-in-crude oil emulsions were prepared, characterized and evaluated. The results were obtained from various characterizations such as Fourier transform infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD), Size Exclusion Chromatography (SEC), Zeta-sizer and Zeta-potential revealed that the polymer were prepared in amorphous form with the variety of particle sizes 30-120 nm. The efficiency of these demulsifiers was tested in water-in-oil emulsions (w/o) at different concentrations (50, 100 and 200 ppm).The results showed that, the nano-demulsifier samples are effective and achieved, the complete separation of the water during 30 min at 200 ppm. Furthermore, the newly formulated samples showed the nano-demulsifier possess very interesting physicochemical properties such as good flow, rheological and remarkable properties at both room and high aging temperature which make them suitable for the injection through the crude oil production pipelines