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51.
Shia T. Kent Samantha G. Bromfield Greer A. Burkholder Louise Falzon Suzanne Oparil Edgar T. Overton Michael J. Mugavero Joseph E. Schwartz Daichi Shimbo Paul Muntner 《PloS one》2016,11(2)
Introduction
Abnormal diurnal blood pressure (BP) rhythms may contribute to the high cardiovascular disease risk in HIV-positive (HIV+) individuals. To synthesize the current literature on ambulatory BP monitoring (ABPM) in HIV+ individuals, a systematic literature review and meta-analysis were performed.Methods
Medical databases were searched through November 11, 2015 for studies that reported ABPM results in HIV+ individuals. Data were extracted by 2 reviewers and pooled differences between HIV+ and HIV-negative (HIV-) individuals in clinic BP and ABPM measures were calculated using random-effects inverse variance weighted models.Results
Of 597 abstracts reviewed, 8 studies with HIV+ cohorts met the inclusion criteria. The 420 HIV+ and 714 HIV- individuals in 7 studies with HIV- comparison groups were pooled for analyses. The pooled absolute nocturnal systolic and diastolic BP declines were 3.16% (95% confidence interval [CI]: 1.13%, 5.20%) and 2.92% (95% CI: 1.64%, 4.19%) less, respectively, in HIV+ versus HIV- individuals. The pooled odds ratio for non-dipping systolic BP (nocturnal systolic BP decline <10%) in HIV+ versus HIV- individuals was 2.72 (95% CI: 1.92, 3.85). Differences in mean clinic, 24-hour, daytime, or nighttime BP were not statistically significant. I2 and heterogeneity chi-squared statistics indicated the presence of high heterogeneity for all outcomes except percent DBP dipping and non-dipping SBP pattern.Conclusions
An abnormal diurnal BP pattern may be more common among HIV+ versus HIV- individuals. However, results were heterogeneous for most BP measures, suggesting more research in this area is needed. 相似文献52.
53.
Unidirectional pulsed-field electrophoresis improves the separation of single-stranded DNA molecules longer than 20 kilobases (kb) in alkaline agarose gels compared to static-field electrophoresis. The greatest improvement in separation is for molecules longer than 100 kb. The improved resolution of long molecules with unidirectional pulsed-field electrophoresis makes possible the measurement of lower frequencies of single-strand breaks. The analytical function that relates the length and mobility of single-stranded DNA electrophoresed with a static field also applies to unidirectional pulsed field separations. Thus, the computer programs used to measure single-strand breaks are applicable to both undirectional pulsed- and static-field separations. Unidirectional pulsed-field electrophoresis also improves the separation of double-stranded DNA in neutral agarose gels. The function relating molecular length and mobility for double-stranded DNA separated by unidirectional pulsed-field electrophoresis is a superset of the function for single-stranded DNA. The coefficients of this function can be determined by iterative procedures. 相似文献
54.
Robert G. Sheath JoAnn M. Burkholder Julie A. Hambrook Amy M. Hogeland Elizabeth Hoy Michael E. Kane Mary O. Morison Alan D. Steinman Kathryn L. Van Alstyne 《Hydrobiologia》1986,140(2):183-191
The Wood River watershed, a small well-defined drainage basin in Rhode Island was monitored seasonally for all macrophytic
vegetation and various physical variables. Twenty-four segments, 20 m in length were sampled. Mean stream depth, width and
current velocity increased by 3 to 8 fold from 1st- to 4th-order segments. Light penetration was positively correlated with
the above variables (p < 0.05) and increased by 11 fold from the headwaters to the mouth during September when the riparian
canopy was maximum. 74 subgeneric taxa of macrophytes were collected in the Wood River basin, 36% algae, 13% bryophytes, 4%
vascular cryptograms and 45% angiosperms. The highest diversity occurred in the 4th-order segments throughout the year. Species
numbers were positively correlated with depth, width and light penetration (p < 0.05). Vascular plants dominated all orders,
but their proportion doubled from 1st- to 4th-order streams. Macrophyte cover was twice as high in the 4th-order segments
in June and September as in the other orders. Macrophyte abundance was positively correlated to light penetration and negatively
correlated to the ratio of nonvascular: vascular plants (p < 0.05). Two distinct clusters were found for the predominant species.
The first cluster contained mostly large angiosperms, which were rooted in sediments, while the second cluster was composed
of small epilithic algae and bryophytes. The moss, Fontinalis antipyretica, was the most frequent species, occurring in 51% of the samples and in all 4 orders throughout the year. 相似文献
55.
Predation on coral spawn by planktivorous fish 总被引:1,自引:1,他引:0
The stomach contents of three species of coral reef fish were examined for changes in diet during the annual mass spawning of scleractinian corals on the Great Barrier Reef, Australia. Acanthochromis polyacanthus, Abudefduf bengalensis (Pomacentridae), and Caesio cuning (Caesionidae) were collected before and immediately after the coral spawning to determine whether the composition of the diet changed after the mass coral spawning. The diet of Caesio cuning did not change. The stomach contents of Acanthochromis and Abudefduf showed that these fish: (1) switched from an omnivorous diet to one consisting predominantly of coral spawn, and (2) that they appeared satiated with stomachs >90% full when coral spawn was present in the water column. Fish predation during coral spawning may be an important source of larval coral mortality. 相似文献
56.
Natalia Soriano-Sarabia Nancie M. Archin Rosalie Bateson Noelle P. Dahl Amanda M. Crooks JoAnn D. Kuruc Carolina Garrido David M. Margolis 《PLoS pathogens》2015,11(10)
Eradication of HIV infection will require the identification of all cellular reservoirs that harbor latent infection. Despite low or lack of CD4 receptor expression on Vδ2 T cells, infection of these cells has previously been reported. We found that upregulation of the CD4 receptor may render primary Vδ2 cells target for HIV infection in vitro and we propose that HIV-induced immune activation may allow infection of γδ T cells in vivo. We assessed the presence of latent HIV infection by measurements of DNA and outgrowth assays within Vδ2 cells in 18 aviremic patients on long-standing antiretroviral therapy. In 14 patients we recovered latent but replication-competent HIV from highly purified Vδ2 cells demonstrating that peripheral Vδ2 T cells are a previously unrecognized reservoir in which latent HIV infection is unexpectedly frequent. 相似文献
57.
58.
JoAnn C. Radway Jorge W. Santo-Domingo Terry C. Hazen Edward W. Wilde 《Biotechnology letters》1998,20(7):663-666
Foam embedded Burkholderia cepacia G4 removed up to 80 % and 60 % of a 3 mg/l solution of trichloroethylene (TCE) and a 2 mg/l solution of benzene, respectively. Removal of TCE and benzene decreased more than 50% when readily metabolizable carbon sources were present. TCE degradative activity was observed with G4 cells induced with phenol or benzene prior or after immobilization of cells. © Rapid Science Ltd. 1998 相似文献
59.
JoAnn S. Roberts Chao Ma Sarah Y.T. Robertson Stephen Kang Christiana S. Han Sophie X. Deng Jie J. Zheng 《Biochemistry and Biophysics Reports》2022
Etodolac is an FDA-approved nonsteroidal anti-inflammatory drug (NSAID) used to treat a variety of inflammatory diseases. The drug is administered as a racemate (50/50 mixture of R- and S- enantiomers), however, studies have shown that the two enantiomers have distinct biologic and pharmacokinetic differences. Wnt signaling, which plays key roles in cell proliferation, polarity, and differentiation, has been shown to be inhibited by R-etodolac; however, comparative analyses of R- and S-etodolac in this function have not been conducted. We used in silico molecular docking and TOPflash functional biologic assays to compare R- and S-enantiomers effect on Wnt signaling inhibition. Further, we used a cultivated limbal stem epithelial cell (cLSCs) model to investigate enantiospecific changes in the colony-forming efficiency (CFE) of cLSCs. The data shows that R-etodolac is a more potent inhibitor of Wnt signaling. In addition, consistently, while both enantiomers demonstrate a dose-dependent decrease in CFE of cLSCs, R-etodolac is a more potent inhibitor. 相似文献
60.
Frahm MA Picking RA Kuruc JD McGee KS Gay CL Eron JJ Hicks CB Tomaras GD Ferrari G 《Journal of immunology (Baltimore, Md. : 1950)》2012,188(9):4289-4296
Previous studies have revealed that HIV-infected individuals possess circulating CD4(+)CD8(+) double-positive (DP) T cells specific for HIV Ags. In the present study, we analyzed the proliferation and functional profile of circulating DP T cells from 30 acutely HIV-infected individuals and 10 chronically HIV-infected viral controllers. The acutely infected group had DP T cells that showed more proliferative capability and multifunctionality than did both their CD4(+) and CD8(+) T cells. DP T cells were found to exhibit greater proliferation and higher multifunctionality compared with CD4 T cells in the viral controller group. The DP T cell response represented 16% of the total anti-HIV proliferative response and >70% of the anti-HIV multifunctional response in the acutely infected subjects. Proliferating DP T cells of the acutely infected subjects responded to all HIV Ag pools with equal magnitude. Conversely, the multifunctional response was focused on the pool representing Nef, Rev, Tat, VPR, and VPU. Meanwhile, the controllers' DP T cells focused on Gag and the Nef, Rev, Tat, VPR, and VPU pool for both their proliferative and multifunctional responses. Finally, we show that the presence of proliferating DP T cells following all HIV Ag stimulations is well correlated with proliferating CD4 T cells whereas multifunctionality appears to be largely independent of multifunctionality in other T cell compartments. Therefore, DP T cells represent a highly reactive cell population during acute HIV infection, which responds independently from the traditional T cell compartments. 相似文献