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Methods to produce rice alcohol by dried traditional yeast are unstable because the yeast system in dried traditional yeast has depended on nature and not been controlled. In this study, a total of 15 different kinds of dried traditional yeast were prepared and screened. Each yeast strain was evaluated by analyzing its fermentation property and alcohol tolerance. There are 19 yeast strains were isolated and their growth conditions and ethanol producing properties were examined. Results showed that three strains S1, BT, BL3 grew and produced ethanol at temperature 28-30oC, and pH 5-5.5. Especially, high concentration ethanol tolerance ability of the three strains was at 8-18%. Our results showed that these strains were valuable microorganisms and could be utilized as a basis for further study of dried traditional yeast in traditional alcoholic beverages.

Background and objectives Treatment guidelines do not recommend antibiotic use for acute respiratory infections (ARI), except for streptococcal pharyngitis/tonsillitis and pneumonia. However, antibiotics are prescribed frequently for children with ARI, often in absence of evidence for bacterial infection. The objectives of this study were 1) to assess the appropriateness of antibiotic prescriptions for mild ARI in paediatric outpatients in relation to available guidelines and detected pathogens, 2) to assess antibiotic use on presentation using questionnaires and detection in urine 3) to assess the carriage rates and proportions of resistant intestinal Enterobacteriaceae before, during and after consultation. Materials and methods Patients were prospectively enrolled in Children’s Hospital 1, Ho Chi Minh City, Vietnam and diagnoses, prescribed therapy and outcome were recorded on first visit and on follow-up after 7 days. Respiratory bacterial and viral pathogens were detected using molecular assays. Antibiotic use before presentation was assessed using questionnaires and urine HPLC. The impact of antibiotic usage on intestinal Enterobacteriaceae was assessed with semi-quantitative culture on agar with and without antibiotics on presentation and after 7 and 28 days. Results A total of 563 patients were enrolled between February 2009 and February 2010. Antibiotics were prescribed for all except 2 of 563 patients. The majority were 2nd and 3rd generation oral cephalosporins and amoxicillin with or without clavulanic acid. Respiratory viruses were detected in respiratory specimens of 72.5% of patients. Antibiotic use was considered inappropriate in 90.1% and 67.5%, based on guidelines and detected pathogens, respectively. On presentation parents reported antibiotic use for 22% of patients, 41% of parents did not know and 37% denied antibiotic use. Among these three groups, six commonly used antibiotics were detected with HPLC in patients’ urine in 49%, 40% and 14%, respectively. Temporary selection of 3rd generation cephalosporin resistant intestinal Enterobacteriaceae during antibiotic use was observed, with co-selection of resistance to aminoglycosides and fluoroquinolones. Conclusions We report overuse and overprescription of antibiotics for uncomplicated ARI with selection of resistant intestinal Enterobacteriaceae, posing a risk for community transmission and persistence in a setting of a highly granular healthcare system and unrestricted access to antibiotics through private pharmacies. Registration This study was registered at the International Standard Randomised Controlled Trials Number registry under number ISRCTN32862422: http://www.isrctn.com/ISRCTN32862422

In this study, we developed and validated two reliable high‐performance liquid chromatography (HPLC) methods for the qualitative detection of six oral β‐lactams, which are commonly used in pediatric patients with acute respiratory infections (ARIs). Two distinct reverse‐phase chromatographic separations of six β‐lactams were obtained. Four β‐lactams (cefadroxil, cephalexin, cefaclor and cefixime) in urine were separated using a gradient program with a mobile phase consisting of K2HPO4 buffer (20 mm, pH 2.8) and acetonitrile on a LichroCART 250 × 4.6 mm, Purospher STAR C18 end‐capped (5 μm) column. Two remained β‐lactams (amoxicillin and cefuroxime) were analyzed using a gradient elution with the mobile phase containing K2HPO4 buffer (20 mm, pH 3.0) and acetonitrile on a LichroCart® Purospher Star C8 end‐capped column (5 μm, 125 × 4.6 mm). Good linearity within the range of 0.3–30 μg/ml for cefadroxil, cephalexin, cefaclor and cefixime, and 0.2–20 μg/ml for amoxicillin and cefuroxime, was attained. The precisions were

The objective of this study was to better understand the molecular mechanisms of microbial adaptation to the cheese habitat by functional genomic approaches using Brevibacterium as a model microorganism. This bacterium is widely used for the manufacturing of cheese but its growth on the cheese surface is sometimes difficult to control.Comparative genomic analysis of 23 Brevibacterium strains, including 12 strains isolated from cheeses, revealed differences in genetic determinants involved in the growth on the cheese surface. Some of them are correlated to strain phylogeny and others are the result of gene transfers, especially those involved in iron acquisition and bacteriocin biosynthesis. We identified genomic islands corresponding to transfers of genes involved in iron acquisition between cheese-associated Brevibacterium strains and cheese-associated strains belonging to other genera. We also detected a conjugative transposon encoding bacteriocin production, which is present in cheese-associated Brevibacterium strains as well as in a cheese-associated Corynebacterium strain.Functional study of biotic interactions between Brevibacterium and Hafnia alvei, another cheese-ripening bacterium, was performed in a model cheese developed in this study. By coupling microbial, biochemical and transcriptomic (RNA-seq) analyses, we revealed several interaction mechanisms between these bacteria. These concern, in particular, iron acquisition, proteolysis, lipolysis, sulfur metabolism and D-galactonate catabolism. Our findings suggest that in the mutualistic relationship between some Brevibacterium strains and H. alvei, the latter stimulates Brevibacterium growth by the secretion of siderophores, which can be used by Brevibacterium to capture iron more efficiently. In return, Brevibacterium secretes lipases and proteases, which degrade cheese caseins and triglycerides into energetic substrates that stimulate H. alvei growth. This type of interaction is interesting to consider in the formulation of ripening cultures because it results in a better ability of all partners to colonize the cheese, and thus to generate the desired technological properties.; L’objectif de ce travail était de mieux comprendre les mécanismes moléculaires de l’adaptation microbienne à l’environnement fromager par des approches de génomique fonctionnelle via le modèle de Brevibacterium, un genre bactérien largement utilisé en technologie fromagère, mais dont l’implantation est parfois difficile à maîtriser.L’analyse génomique comparative de 23 souches de Brevibacterium, dont 12 issues de fromages, a révélé des différences en déterminants génétiques impliqués dans la capacité à croître à la surface du fromage. Parmi ces différences, plusieurs sont corrélées à la phylogénie des souches, et d’autres résultent de transferts horizontaux, notamment dans le cas des gènes liés à l’acquisition du fer et à la biosynthèse de bactériocines. Nous avons identifié des îlots génomiques correspondant à des transferts de gènes d’acquisition du fer entre des souches fromagères de Brevibacterium et des bactéries d’affinage appartenant à d’autres genres. Nous avons également mis en évidence un transposon conjugatif codant pour la synthèse de bactériocines présent chez des souches de Brevibacterium d'origine fromagère mais aussi chez une souche fromagère du genre Corynebacterium.L’étude fonctionnelle des interactions biotiques entre Brevibacterium et Hafnia alvei, une autre bactérie d’affinage du fromage, a été menée dans un modèle fromager développé au cours de ce travail. En couplant des analyses microbiologiques, biochimiques et transcriptomiques (RNA-seq), nous avons mis en évidence l’existence de différents mécanismes d’interaction entre ces bactéries. Ceux-ci concernent notamment l’acquisition du fer, la protéolyse, la lipolyse, le métabolisme soufré et le catabolisme du D-galactonate. Nos résultats suggèrent que dans la relation mutualiste observée entre certaines souches de Brevibacterium et H. alvei, cette dernière sécrète des sidérophores qui sont utilisés par Brevibacterium pour capter le fer plus efficacement, stimulant ainsi sa croissance. En contrepartie, Brevibacterium sécrète des lipases et des protéases qui dégradent les caséines et triglycérides du fromage en constituants énergétiques favorisant la croissance de H. alvei. Ce type d’interaction est intéressant à considérer pour la formulation des ferments d'affinage car il en résulte une meilleure capacité de tous les partenaires à coloniser le fromage, et ainsi à générer les propriétés technologiques recherchées.

An accurate and reliable high-performance liquid chromatography with time-programmed fluorescence detection was developed and validated to measure levofloxacin in human plasma and cerebrospinal fluid (CSF). After solid phase extraction process using Evolute ® ABN 96 fixed well plate; levofloxacin and internal standard-enoxacin were separated using a mobile phase consisting of phosphate buffer 10 mM with 0.025% triethylamine pH 3.0 - acetonitrile (88:12, v/v) on a Purosphere RP-8e column (5 μm, 125 × 4.0mm) at a flow rate of 1.2 mL/min at 35 °C. The excitation/emission wavelengths were set to 269/400 nm and 294/500 nm, for enoxacin and levofloxacin, respectively. The method was linear over the concentration range of 0.02 to 20.0 μg/mL with a limit of detection of 0.01 μg/mL. The relative standard deviation of intra-assay and inter-assay precision for levofloxacin at four quality controls concentrations (0.02, 0.06, 3.0 and 15.0 μg/mL) were less than 7% and the accuracies ranged from 96.75% to 101.9% in plasma, and from 93.00% to 98.67% in CSF. The validated method was successfully applied to quantify levofloxacin in a considerable quantity of plasma (826) and CSF (477) samples collected from 232 tuberculous meningitis patients, and the preliminary intensive pharmacokinetics analysis from 14 tuberculous meningitis patients in Vietnam is described in this paper.

BACKGROUND\ud Among the various forms of TB, tuberculous meningitis (TBM) is the most severe, with about 30% mortality and 50% of survivors left with neurological sequelae. Children suffer more frequently from TBM than adults and outcomes are often poor due to difficulties in making the diagnosis and uncertainty regarding the best anti-tuberculosis drug regimen. The aim of this prospective study was to describe the pharmacokinetics of pyrazinamide, isoniazid and rifampicin in plasma and cerebrospinal fluid of children with tuberculous meningitis treated with the standard TBM regimen.\ud \ud METHODS\ud We performed a prospective observational study of 100 consecutively treated children (≤ 15 years of age) with tuberculous meningitis in Ho Chi Minh City, Vietnam. Children were treated according to the 2006 WHO recommended pediatric treatment regimen consisting of isoniazid (5 mg/kg), rifampicin (10 mg/kg) and ethambutol (15 mg/kg) for 8 months, with the addition of pyrazinamide (25 mg/kg) for the first 3 months and streptomycin (15 mg/kg) for the first 2 months. Pyrazinamide, isoniazid and rifampicin concentrations were measured in plasma at day 14 and in cerebrospinal fluid (CSF) at 1 month by HPLC-UV. A naïve-pooled non-compartmental data analysis was used to describe the pharmacokinetic properties of drugs in the two-age groups of children ≤ 4 years or > 4 years of age.\ud \ud RESULTS\ud Younger children, when compared to older children, presented a higher body weight-normalized clearance and volume of distribution, and lower median total plasma exposures for the three studied drugs with -14%, -22% and -16% for Pyrazinamide, Isoniazid and Rifampicin, respectively. In CSF, individual concentrations of isoniazid and pyrazinamide were comparable to that in plasma in both age groups; but rifampicin concentrations were lower than the minimum inhibitory concentration of susceptible bacteria in all but two children.\ud \ud CONCLUSIONS\ud There is an age-dependent variation in the plasma and cerebrospinal fluid pharmacokinetics of rifampicin, isoniazid and pyrazinamide. The safety and efficacy of higher doses of rifampicin should be investigated for the treatment of childhood tuberculous meningitis.