Bacterial community variations in the South China Sea driven by different chemical conditions

In this study, Illumina MiSeq sequencing of the 16 S rRNA gene was used to describe the bacterial communities in the South China Sea (SCS) during the southwest monsoon period. We targeted different regions in the SCS and showed that bacterial community was driven by the effects of the river, upwelling, and mesoscale eddy through changing the environmental factors (salinity, temperature, and nutrients). Distinct bacterial communities were observed among different chemical conditions, especially between the estuary and the open sea. The abundance of Burkholderiales, Frankiales, Flavobacteriales, and Rhodobacterales dominated the estuary and its adjacent waters. Bacteria in cyclonic eddy were dominated by Methylophilales and Pseudomonadales, whereas Prochlorococcus, SAR11 clade, and Oceanospirillales had relatively high abundance in the anticyclonic eddy. Overall, the abundance of specific phylotypes significantly varied among samples with different chemical conditions. Chemical conditions probably act as a driver that shapes and controls the diversity of bacteria in the SCS. This study suggests that the interaction between microbial and environmental conditions needs to be further considered to fully understand the diversity and function of marine microbes.

     

Spatial variation of bacterial community structure of the Northern South China Sea in relation to water chemistry

Spatial distribution, diversity and composition of bacterial communities of the northern South China Sea (SCS) surface water and the relationship with the in situ environmental chemistry were investigated. Polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE) was used to investigate the bacterial community structure. The DGGE gel showed that each sample harbored a distinct bacterial community structure and spatial variations of bacterial community composition among all samples were obviously. A total of 17 intensive bands were excised and the sequence analysis of these DGGE bands revealed that Proteobacteria were the dominant bacterial group of surface water in the north part of SCS. Results of the taxonomic analysis showed that the communities consisted of Proteobacteria (α-subdivision, β-subdivision, γ-subdivision), Actinobacteria, Cyanobacteria, Bacteroidetes and Firmicutes. Unweighted pair group method with arithmetic averages clustering of the sampling stations indicated that all stations were classified mainly based on geographical proximity. Canonical correspondence analysis (CCA) was employed to further investigate the relationships between DGGE band pattern and the environmental variables and the first two CCA ordination axes suggested that the structure of the bacterial community was significantly correlated with the variables of nitrate (F = 1.24, P < 0.05).     

Microbial community structure shifts and potential Symbiodinium partner bacterial groups of bleaching coral Pocillopora verrucosa in South China Sea

Ecotoxicology - The community structure of coral associated microorganisms will change greatly in coral bleaching. However, the relationship between specific bacteria groups and Symbiodinium, which...     

近红外光谱—偏最小二乘方法同时测定复方磺胺甲唑片的两种有效成分

目的建立复方磺胺甲口恶唑片的两种有效成分磺胺甲口恶唑(SMZ)和甲氧苄啶(TMP)的快速同时测定方法。方法基于近红外漫反射光谱技术,利用偏最小二乘方法建立该复方中SMZ和TMP的定量分析多元校正模型。结果对于所建立的SMZ与TMP模型,相关系数分别为:100.00%与100.00%;校正集残差分别为:0.0163与0.008 36;预测均方差分别为:0.156与0.0815。结论本方法在样品不经任何预处理的情况下,实现了该制剂的两种有效成分SMZ和TMP的简单、快速、两组分同时准确测定。     

Simultaneous spectrophotometric determination of valsartan and hydrochlorothiazide by H-point standard addition method and partial least squares regression

Simultaneous determination of valsartan and hydrochlorothiazide by the H-point standard additions method (HPSAM) and partial least squares (PLS) calibration is described. Absorbances at a pair of wavelengths, 216 and 228 nm, were monitored with the addition of standard solutions of valsartan. Results of applying HPSAM showed that valsartan and hydrochlorothiazide can be determined simultaneously at concentration ratios varying from 20:1 to 1:15 in a mixed sample. The proposed PLS method does not require chemical separation and spectral graphical procedures for quantitative resolution of mixtures containing the titled compounds. The calibration model was based on absorption spectra in the 200-350 nm range for 25 different mixtures of valsartan and hydrochlorothiazide. Calibration matrices contained 0.5-3 μg mL-1 of both valsartan and hydrochlorothiazide. The standard error of prediction (SEP) for valsartan and hydrochlorothiazide was 0.020 and 0.038 μg mL-1, respectively. Both proposed methods were successfully applied to the determination of valsartan and hydrochlorothiazide in several synthetic and real matrix samples.     

Native state of metals in non-digested tissues by partial least squares regression analysis of visible and near-infrared spectra

A procedure has been used for the classification and quantification of metals on the basis of a chemometric analysis of visible and near-infrared (Vis-NIR) spectra of metals such as Cu, Mn and Fe in the brain, liver, kidney and testis of mice without digestion. Transmittance spectra in the 600- to 1000-nm region subjected to partial least-squares (PLS) regression analysis and leave-out cross-validation facilitated development of chemometrics models for predicting metal concentration. From the models, Cu, Mn and Fe yielded the coefficients of determination in cross-validation (R(2)(VAL)) as 0.8013, 0.9021 and 0.8295 with standard errors of cross-validation (SECV) of 3.399, 0.8237 and 76.512 microg per g tissue, respectively. The respective detection limits of Cu, Mn and Fe were 12.19, 2.616 and 266.32 microg per g tissue. Furthermore, the regression coefficients of the models showed specific patterns for the respective metals. These results suggest that Vis-NIR spectroscopy may have a great potential for analysis of native state of metals in tissues.     

Direct determination of diclofenac in pharmaceutical formulations containing B vitamins by using UV spectrophotometry and partial least squares regression

This work proposes a simple and rapid analytical procedure for determination of diclofenac (DCF) in the presence of B vitamins, based on UV measurements and partial least squares (PLS). The interference of thiamine (THI) and pyridoxine (PYR) were modelled using an experimental design constructed in the ranges of 10-50 micromoll(-1) for DCF and THI and 15-75 micromoll(-1) for PYR. The procedure was repeated at five different pH values (between 3 and 6) and the best results were observed at pH 5, presenting a root mean square error of prediction (RMSEP) of 0.80 micromoll(-1) for DCF. The procedure was successfully applied to simultaneous determination of DCF, THI and PYR in synthetic mixtures and in a pharmaceutical formulation that contains a simple excipient (lactose). For determination of a more complex formulation that contains 15 different substances in the excipient, including some UV absorbing ones, the procedure was only able to determine DCF, since the excipient interferences disturbed THI and PYR predictions. Figures of merit, such as selectivity, analytical sensitivity, limit of detection and precision were determined for the DCF prediction model and the determinations were verified by an independent method, HPLC.     

Phytoplankton diversity and community responses to physicochemical variables in mangrove zones of Guangzhou Province,China

Ecotoxicology - The phytoplankton diversity and community response to physicochemical variables in mangrove zones of Guangdong Province along the South China coast was investigated from October to...     

The influence of assay error weight on gentamicin pharmacokinetics using the bayesian and nonlinear least square regression analysis in appendicitis patients

The purpose of this study was to determine the influence of weight with gentamicin assay error on the Bayesian and nonlinear least squares regression analysis in 12 Korean appendicitis patients. Gentamicin was administered intravenously over 0.5 h every 8 h. Three specimens were collected at 48 h after the first dose from all patients at the following times, just before regularly scheduled infusion, at 0.5 h and 2 h after the end of 0.5 h infusion. Serum gentamicin levels were analyzed by fluorescence polarization immunoassay technique with TDxFLx. The standard deviation (SD) of the assay over its working range had been determined at the serum gentamicin concentrations of 0, 2, 4, 8, 12, and 16 microg/mL in quadruplicate. The polynominal equation of gentamicin assay error was found to be SD (microg/mL) = 0.0246 - (0.0495C) + (0.00203C2). There were differences in the influence of weight with gentamicin assay error on pharmacokinetic parameters of gentamicin using the nonlinear least squares regression analysis but there were no differences on the Bayesian analysis. This polynominal equation can be used to improve the precision of fitting of pharmacokinetic models to optimize the process of model simulation both for population and for individualized pharmacokinetic models. The result would be improved dosage regimens and better, safer care of patients receiving gentamicin.     

The epidemiology of fetal alcohol syndrome and partial FAS in a South African community

OBJECTIVES: The prevalence and characteristics of fetal alcohol syndrome (FAS) and partial fetal alcohol syndrome (PFAS) were determined in a third primary school cohort in a community in South Africa (SA). METHODS: An active case ascertainment, two-tier screening methodology, and the revised Institute of Medicine diagnostic criteria were employed among 818 first grade pupils. Characteristics of children with FAS and PFAS are contrasted with a randomly selected control group. Data were collected and analyzed for children in the study regarding: (1) physical growth and development, including dysmorphology, (2) intelligence and behavioral characteristics, and (3) their mother's social, behavioral, and physical characteristics. RESULTS: The rate of FAS and PFAS in this area continues as the highest reported in any overall community and is much higher than rates elsewhere. In this cohort it is 68.0-89.2 per 1000. Severe episodic drinking on weekends among mothers of children with FAS and PFAS accounts for 96% of all alcohol consumed. Various measures of maternal drinking are significantly correlated with negative outcomes of children in the areas of non-verbal intelligence (-0.26), verbal intelligence (-0.28), problem behavior (0.31), and overall dysmorphology score (0.59). Significantly more FAS and PFAS exists among children of rural residents (OR=3.79). CONCLUSIONS: A high rate of FAS and PFAS was again documented in this community, and it has increased. Given population similarities, we suspect that other communities in the Western Cape Province of South Africa also have high rates. Programs for prevention are needed.     

The influence of weight with assay error on gentamicin pharmacokinetics using the Bayesian and nonlinear least square regression analysis in appendicitis patients

The purpose of this study was to determine the influence of weight with gentamicin assay error on the Bayesian and nonlinear least squares regression analysis in 12 Korean appendicitis patients. Gentamicin was administered intravenously over 0.5 h every 8 h. Three specimens were collected 48 h after the first dose from all patients at the following times, just before the regularly scheduled infusion, at 0.5 h and 2 h after the end of the 0.5 h infusion. Serum gentamicin levels were analysed by fluorescence polarization immunoassay technique with TDxFLx. The standard deviation (SD) of the assay over its working range had been determined at the serum gentamicin concentrations of 0, 2, 4, 8, 12 and 16 microg/ml in quadruplicate. The polynominal equation of gentamicin assay error was found to be SD (microg/ml) = 0.0246-(0.0495C) + (0.00203C(2)). There were differences in the influence of weight with gentamicin assay error on pharmacokinetic parameters of gentamicin using the nonlinear least squares regression analysis but there were no differences on the Bayesian analysis. This polynominal equation can be used to improve the precision of fitting of pharmacokinetic models to optimize the process of model simulation both for population and for individualized pharmacokinetic models. The result would be improved dosage regimens and the better, safer care of patients receiving gentamicin.     

基于灰色关联度和偏最小二乘回归分析的芩苏胶囊抑菌谱效关系研究

目的 基于灰色关联度法和偏最小二乘法研究芩苏胶囊抑菌作用的谱效关系。方法 使用高效液相色谱(HPLC)法建立10批芩苏胶囊的指纹图谱,采用管碟法测定芩苏胶囊(0.3 g·mL^-1)对5种常见致病菌(金黄色葡萄球菌、大肠埃希菌、铜绿假单胞菌、肺炎克雷伯菌、肺炎链球菌)的抑菌活性,使用灰色关联度分析法结合偏最小二乘法构建谱效关系。结果 10批样品指纹图谱中有37个共有峰,芩苏胶囊对5种致病菌均具有一定的抑菌作用,对金黄色葡萄球菌有较好的抑菌作用。6、10(迷迭香酸)、14、17(丹酚酸B)号峰为芩苏胶囊抑制金黄色葡萄球菌的主要成分;10(迷迭香酸)、17(丹酚酸B)、35(苦参碱)、37(氧化苦参碱)号峰为抑制大肠埃希菌的主要成分;6、7、8、9、10(迷迭香酸)、14、17(丹酚酸B)、27、31(丹参酮Ⅰ)、37(氧化苦参碱)号峰为抑制铜绿假单胞菌的主要成分;8、9、10(迷迭香酸)、14、17(丹酚酸B)、37(氧化苦参碱)为抑制肺炎克雷伯菌的主要成分;5、23(汉黄芩素)、27、30、31(丹参酮Ⅰ)、32、33(丹参酮Ⅱ_A)、34(槐果碱)、36(氧化槐定碱)、37(氧化苦参碱)号峰为抑制肺炎链球菌的主要成分。结论 通过谱效关系研究明确了芩苏胶囊抑菌药效作用是多种成分共同作用的结果,可为芩苏胶囊的药效物质基础研究与质量控制提供参考。     

一种南海软珊瑚多糖的提取、分离及活性评价D

目的 从南海软珊瑚Sinularia sp.中提取、分离和纯化多糖,分析其基本理化性质,并对其生物活性进行初步评价。方法 采用酸性蛋白酶从软珊瑚Sinularia sp.中提取粗多糖,利用碱性蛋白酶和732型阳离子交换树脂去除蛋白,利用Q Sepharose Fast Flow强阴离子交换柱层析对多糖进行分离纯化,并对多糖组分进行总糖含量、蛋白含量和单糖组成分析。将得到的多糖组分采用三氧化硫-吡啶法进行硫酸酯化修饰并对其进行抗病毒、抗凝血生物活性评价。结果 从软珊瑚Sinularia sp.中提取分离得到3种多糖组分,单糖组成较复杂,主要含有Ara, Gal及Rha;软珊瑚多糖硫酸酯可以明显抑制HBsAg和HBeAg的表达量;体外抗凝实验中可延长APTT和PT值。结论 从软珊瑚Sinularia sp.中得到了3种多糖组分,硫酸酯化修饰的软珊瑚多糖具有良好的抗病毒、抗凝血活性,为软珊瑚多糖的深入研究提供了基础。