emperature and oil,and has a stable dis

ld,so we present the well logging series and gas drilling technique suited to Daqing area.Some proper logging evaluation approaches are used such as GR spectrometry log,CN log,induction log and NMR log,etc.well logging;technology;gas drilling;foam drilling;casing drilling;Daqing oilfield0测井技术Well Logging Technology20-22 104P631.8B019;B021;A011;A012;C;21;D3;A;B;B019_21;A011_D3;A012_C;B021_21;赵平;16-18 100高孔密复合射孔技术研究周志华;谭忠健;刘富奎;西安通源石油科技股份有限公司,中海石油(中国)有限公司天津分公司勘探部,中海石油(中国)有限公司天津分公司勘探部 陕西西安710065,天津300452,天津300452复合射孔;;高孔密;;p-t过程测试;;现场应用提出了一种新型装药结构并实现在高孔密条件下的复合射孔,所开发的产品进行了地面混凝土靶测试、地面动态压力-时间(p-t)过程测试和现场应用试验。试验结果表明,高孔密复合射孔器能够将高孔密的多孔道、多相位的射孔特点与高能气体压裂造缝机理有机地结合,形成了孔缝结合的深穿透、高孔密和多相位的沟通通道,有效地改善了近井带的渗流能力,实现了油井的高产和稳产。现场应用效果良好。On High Foramen Density Technology for the Fracture Perfo     

Hepatic antioxidant status and hematological parameters in rainbow trout,Oncorhynchus mykiss,after chronic exposure to carbamazepine

Recently, residual pharmaceuticals are generally recognized as relevant sources of aquatic environmental pollutants. However, the toxicological effects of these contaminants have not been adequately researched. In this study, the chronic toxic effect of carbamazepine (CBZ), an anticonvulsant drug commonly present in surface and ground water, on hepatic antioxidant status and hematological parameters of rainbow trout were investigated. Fish were exposed at sublethal concentrations of CBZ (1.0 μg/l, 0.2 mg/l and 2.0 mg/l) for 7, 21 and 42 days. Compared to the control group, fish exposed at higher concentration (0.2 mg/l or 2.0 mg/l) of CBZ showed significantly higher levels of hemoglobin, ammonia and glucose, and significantly higher plasma enzymes activities. During the exposure duration, erythrocyte count, hematocrit, mean erythrocyte hemoglobin, mean erythrocyte volume, mean color concentration and total protein content in all groups were not significantly different. At the highest test concentration (2.0 mg/l) of CBZ, oxidative stress was apparent as reflected by the significant higher lipid peroxidation and protein carbonyl levels in liver after 42 days exposure, associated with an inability to induce antioxidant enzymes activities including superoxide dismutase, glutathione peroxidase and glutathione reductase. After 42 days exposure, reduced glutathione level was significantly decreased in the fish exposed at 0.2 mg/l CBZ, compared with the control. In short, CBZ-induced physiological and biochemical responses in fish were reflected in the oxidant stress indices and hematological parameters. These results suggest that hepatic antioxidant responses and hematological parameter could be used as potential biomarkers for monitoring residual pharmaceuticals present in aquatic environment.     

Influence of environmental related concentrations of heavy metals on motility parameters and antioxidant responses in sturgeon sperm

The effects of heavy metals (Cd, Cr and Cd + Cr) on the motility parameters and oxidative stress of sterlet (Acipenser ruthenus) sperm were investigated in vitro. Sturgeon sperm were exposed for 2 h to heavy metals at environmental related concentrations (0.1 mg L^?1 Cr, 0.001 mg L^?1 Cd, 0.1 mg L^?1 Cr + 0.001 mg L^?1 Cd) and higher concentrations (5.0 mg L^?1 Cr, 0.05 mg L^?1 Cd, 5.0 mg L^?1 Cr + 0.05 mg L^?1 Cd). Results revealed that environmental concentrations of heavy metals had no significant influence on motility parameters and antioxidant responses indices in sturgeon sperm, except for LPO level and SOD activity. But higher concentrations of these metals induced oxidative tress in sturgeon sperm in vitro, associated with sperm motility parameters inhibition. Our results suggest that using of sperm in vitro assays may provide a novel and efficiently means for evaluating the effects of residual heavy metals in aquatic environment on sturgeon.     

Shifty salamanders: transient trophic polymorphism and cannibalism within natural populations of larval ambystomatid salamanders

Introduction

Many species of ambystomatid salamanders are dependent upon highly variable temporary wetlands for larval development. High larval densities may prompt the expression of a distinct head morphology that may facilitate cannibalism. However, few studies have characterized structural cannibalism within natural populations of larval salamanders. In this study we used two species of larval salamanders, long-toed (Ambystoma macrodactylum) and ringed salamanders (A. annulatum). Head morphometrics and stable isotopic values of carbon (δ¹³C) and nitrogen (δ¹⁵N) were used to identify the presence or absence of structural cannibalism. Weather conditions were also analyzed as a potential factor associated with the expression of cannibalistic morphology.

Results

Populations of salamander larvae did not consistently exhibit cannibalistic morphologies throughout collection periods. Larval long-toed salamanders exhibited trophic polymorphisms when relatively lower precipitation amounts were observed. Larval ringed salamanders were observed to be cannibalistic but did not exhibit polymorphisms in this study.

Conclusions

Structural cannibalism may be transient in both species; however in long-toed salamanders this morphology is necessary for cannibalism. Ringed salamanders can be cannibalistic without morphological adaptations; however the cannibal morph may prolong the viable time period for cannibalism. Additionally, weather conditions may alter pond hydroperiod, subsequently influencing head morphology and cannibalism.

     

Biochemical responses in gills of rainbow trout exposed to propiconazole

The aim of this study is to investigate the toxic effect of PCZ, a triazole fungicide commonly present in surface and ground water, on the ROS defense system and Na₊-K₊-ATPase in gills of rainbow trout exposed to sublethal concentrations (0.2, 50 and 500 μg L⁻¹) for 7, 20 and 30 days. After prolonged exposure of PCZ at higher test concentrations (50 and 500 μg L⁻¹), oxidative stress was apparent as reflected by the significant higher ROS levels in fish gill, as well as the significant inhibition of SOD and CAT activities. In addition, Na₊-K₊-ATPase activities were significantly lower than those of the control with increasing PCZ concentration and prolonged exposure period. The results of this study indicate that chronic exposure to PCZ has altered multiple physiological indices in fish gill; however, before these parameters are used as unique biomarkers for monitoring residual pharmaceuticals in aquatic environments, more detailed laboratory experiments need to be performed.     

X4 tropic multi-drug resistant quasi-species detected at the time of primary HIV-1 infection remain exclusive or at least dominant far from PHI

Our objective was to analyze the evolution of resistance mutations (RM) and viral tropism of multi-drug-resistant (MDR) strains detected at primary HIV-1 infection (PHI). MDR HIV strain was defined as the presence of genotypic resistance to at least 1 antiretroviral of the 3 classes. Tropism determinations (CCR5 or CXCR4) were performed on baseline plasma HIV-RNA and/or PBMC-HIV-DNA samples, then during follow-up using population-based sequencing of V3 loop and phenotypic tests. Clonal analysis was performed at baseline for env, RT and protease genes, and for HIV-DNA env gene during follow-up. Five patients were eligible. At baseline, RT, protease and env clones from HIV-RNA and HIV-DNA were highly homogenous for each patient; genotypic tropism was R5 in 3 (A,B,C) and X4 in 2 patients (D,E). MDR strains persisted in HIV-DNA throughout follow-up in all patients. For patient A, tropism remained R5 with concordance between phenotypic and genotypic tests. Clonal analysis on Month (M) 78 HIV-DNA evidenced exclusively R5 (21/21) variants. In patient B, clonal analysis at M36 showed exclusively R5 variants (19/19) using both genotypic and phenotypic tests. In patient C, baseline tropism was R5 by genotypic test and R5/X4 by phenotypic test. An expansion of these X4 clones was evidenced by clonal analysis on M72 HIV-DNA (12/14 X4 and 2/14 R5 variants). In patient D, baseline tropism was X4 with concordance between both techniques and HIV-RNA and HIV-DNA remained X4-tropic up to M72, confirmed by the clonal analysis. Patient E harboured highly homogenous X4-using population at baseline; tropism was unchanged at M1 and M18. In all patients, the initial MDR population was highly homogenous initially, supporting the early expansion of a monoclonal population and its long-term persistence. X4-tropic variants present at baseline were still exclusive (patients D and E) or dominant (at least one time point, patient C) far from PHI.     

A mutation in CFTR modifies the effects of the adenylate kinase inhibitor Ap5A on channel gating

Mutations in the gene that encodes the cystic fibrosis transmembrane conductance regulator (CFTR) cause cystic fibrosis. The CFTR anion channel is controlled by ATP binding and enzymatic activity at the two nucleotide-binding domains. CFTR exhibits two types of enzymatic activity: 1), ATPase activity in the presence of ATP and 2), adenylate kinase activity in the presence of ATP plus physiologic concentrations of AMP or ADP. Previous work showed that P¹,P⁵-di(adenosine-5′)pentaphosphate (Ap₅A), a specific adenylate kinases inhibitor, inhibited wild-type CFTR. In this study, we report that Ap₅A increased activity of CFTR with an L1254A mutation. This mutation increased the EC50 for ATP by >10-fold and reduced channel activity by prolonging the closed state. Ap₅A did not elicit current on its own nor did it alter ATP EC50 or maximal current. However, it changed the relationship between ATP concentration and current. At submaximal ATP concentrations, Ap₅A stimulated current by stabilizing the channel open state. Whereas previous work indicated that adenylate kinase activity regulated channel opening, our data suggest that Ap₅A binding may also influence channel closing. These results also suggest that a better understanding of the adenylate kinase activity of CFTR may be of value in developing new therapeutic strategies for cystic fibrosis.     

Durability and Effectiveness of Maraviroc-Containing Regimens in HIV-1-Infected Individuals with Virological Failure in Routine Clinical Practice

Introduction

Limited data are available on the durability and effectiveness of maraviroc in routine clinical practice. We assessed the durability of maraviroc-containing regimens during a 30-month period, as well as their immunovirological and clinical efficacy, according to viral tropism in treatment-experienced individuals with viral load (VL) >50 copies/ml in the French Hospital Database on HIV.

Methods

Virological success was defined as VL<50 copies/ml, immunological success as a confirmed increase of at least 100 CD4 cells/mm³ measured twice at least one month apart, and clinical failure as hospitalization for a non-AIDS event, an AIDS event, or death. Multivariable Cox regression models adjusted for potential confounders were used to assess the influence of viral tropism on durability, the immunovirological responses, and clinical outcome.

Results

356 individuals started maraviroc with VL>50 copies/ml of whom 223 harbored R5 viruses, 44 non-R5 viruses and 89 viruses of unknown tropism. Individuals with non-R5 viruses were more likely than individuals with R5 viruses to discontinue maraviroc (75% vs 34%, p<0.0001). At 30 months, the estimated rates of virological and immunological success were respectively 89% and 51% in individuals with R5 viruses and 48% and 23% in individuals with non-R5 viruses. In multivariable analysis, non-R5 viruses were associated with a lower likelihood of both virological success (hazard ratio (HR): 0.42; 95% confidence interval (CI), 0.25–0.70) and immunological success (HR: 0.37; 95% CI, 0.18–0.77). No difference in clinical outcome was found between individuals with R5 and non-R5 viruses. The effectiveness of maraviroc-containing regimens in individuals with unknown viral tropism was not significantly different from that in individuals with R5 viruses. A limitation of the study is the absence of genotypic susceptibility score.

Conclusion

In this observational study, maraviroc-containing regimens yielded high rates of viral suppression and immunological responses in individuals with R5 viruses in whom prior regimens had failed.     

Ecotoxocological effects of short-term exposure to a human pharmaceutical Verapamil in juvenile rainbow trout (Oncorhynchus mykiss)

Verapamil (VRP) is a calcium channel blocker that is a highly prescribed compound and commonly present in aquatic environment, but the ecotoxicological effects of this pharmaceutical in fish have not been fully documented. In this study, the toxic effects of VRP were studied in juvenile rainbow trout, Oncorhynchus mykiss, by acute static bioassay. In the acute test, the median lethal concentration (LC50, 2.72 mg/L) was evaluated and the behavioral changes were obviously intensified with increasing VRP concentrations. Compared to the control, oxidative stress was observed in fish tissues with different levels after short-term exposure to sublethal concentrations (0.27 and 1.35 mg/L) of VRP. Activities of SOD and GPx in fish brain were induced at 0.27 mg/L VRP, but all the antioxidant enzymes (SOD, GPx and GR) in fish brain were decreased at 1.35 mg/L VRP. When compared to the control, all the antioxidant enzymes in gill were decreased in both treated groups, but there was no significant change in muscle. Additional, muscle DNA/RNA ratio in fish exposed at 1.35 mg/L VRP was significantly lower than that in the control. Furthermore, through chemometrics of all parameters measured in fish exposed to sublethal VRP concentrations using principal component analysis, two groups with 89.8% of total accumulated variance were distinguished. In short, the physiological and biochemical responses in of fish indicated that VRP-induced environmental stress; but according to VRP residual status in the natural environment, more long-term experiments at lower concentrations will be necessary in the future.