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341.
Dana R. Thompson Florence M. Momplaisir Jo?lla W. Adams Baligh R. Yehia Emily A. Anderson Gregg Alleyne Kathleen A. Brady 《PloS one》2015,10(12)
Objective
Current guidelines call for HIV-infected women to deliver via scheduled Caesarean when the maternal HIV viral load (VL) is >1,000 copies/ml. We describe the mode of delivery among HIV-infected women and evaluate adherence to relevant recommendations.Study Design
We performed a population-based surveillance analysis of HIV-infected pregnant women in Philadelphia from 2005 to 2013, comparing mode of delivery (vaginal, scheduled Caesarean, or emergent Caesarean) by VL during pregnancy, closest to the time of delivery (≤1,000 copies/ml versus an unknown VL or VL >1,000 copies/ml) and associated factors in multivariable analysis.Results
Our cohort included 824 deliveries from 648 HIV-infected women, of whom 69.4% had a VL ≤1,000 copies/ml and 30.6% lacked a VL or had a VL >1,000 copies/ml during pregnancy, closest to the time of delivery. Mode of delivery varied by VL: 56.6% of births were vaginal, 30.1% scheduled Caesarean, and 13.3% emergent Caesarean when the VL was ≤1,000 copies/ml; when the VL was unknown or >1,000 copies/ml, 32.9% of births were vaginal, 49.9% scheduled Caesarean and 17.5% emergent Caesarean. In multivariable analyses, Hispanic women (adjusted odds ratio (AOR) 0.17, 95% Confidence Interval (CI) 0.04–0.76) and non-Hispanic black women (AOR 0.27, 95% CI 0.10–0.77) were less to likely to deliver via scheduled Caesarean compared to non-Hispanic white women. Women who delivered prior to 38 weeks’ gestation (AOR 0.37, 95% CI 0.18–0.76) were also less likely to deliver via scheduled Caesarean compared to women who delivered after 38 weeks’ gestation. An interaction term for race and gestational age at delivery was significant in multivariable analysis. Non-Hispanic black (AOR 0.06, 95% CI 0.01–0.36) and Hispanic women (AOR 0.03, 95% CI 0.00–0.59) were more likely to deliver prematurely and less likely to deliver via scheduled C-section compared to non-Hispanic white women. Having a previous Caesarean (AOR 27.77, 95% CI 8.94–86.18) increased the odds of scheduled Caesarean delivery.Conclusions
Only half of deliveries for women with an unknown VL or VL >1,000 copies/ml occurred via scheduled Caesarean. Delivery prior to 38 weeks, particularly among minority women, resulted in a missed opportunity to receive a scheduled Caesarean. However, even when delivering at or after 38 weeks’ gestation, a significant proportion of women did not get a scheduled Caesarean when indicated, suggesting a need for focused public health interventions to increase the proportion of women achieving viral suppression during pregnancy and delivering via scheduled Caesarean when indicated. 相似文献342.
Circadian rhythms are certain periodic behaviours exhibited by living organism at different levels, including cellular and system-wide scales. Recent studies have found that the circadian rhythms of several peripheral organs in mammals, such as the liver, are able to entrain their clocks to received signals independent of other system level clocks, in particular when responding to signals generated during feeding. These studies have found SIRT1, PARP1, and HSF1 proteins to be the major influencers of the core CLOCKBMAL1:PER-CRY circadian clock. These entities, along with abstracted feeding induced signals were modelled collectively in this study using Petri Nets. The properties of the model show that the circadian system itself is strongly robust, and is able to continually evolve. The modelled feeding regimens suggest that the usual 3 meals/day and 2 meals/day feeding regimens are beneficial with any more or less meals/day negatively affecting the system. 相似文献
343.
John Haskew Veronica Kenyi Juma William Rebecca Alum Anu Puri Yehia Mostafa Robert Davis 《PloS one》2015,10(8)
Background
Use of mobile information technology may aid collection of real-time, standardised data to inform and improve decision-making for polio programming and response. We utilised Android-based smartphones to collect data electronically from more than 8,000 households during a national round of polio immunisation in South Sudan. The results of the household surveys are presented here, together with discussion of the application of mobile information technology for polio campaign planning, implementation and evaluation in a real-time setting.Methods
Electronic questionnaires were programmed onto Android-based smartphones for mapping, supervision and survey activities during a national round of polio immunisation. National census data were used to determine the sampling frame for each activity and select the payam (district). Individual supervisors, in consultation with the local district health team, selected villages and households within each payam. Data visualisation tools were utilised for analysis and reporting.Results
Implementation of mobile information technology and local management was feasible during a national round of polio immunisation in South Sudan. Red Cross visits during the polio campaign were equitable according to household wealth index and households who received a Red Cross visit had significantly higher odds of being aware of the polio campaign than those who did not. Nearly 95% of children under five were reported to have received polio immunisation (according to maternal recall) during the immunisation round, which varied by state, county and payam. A total of 11 payams surveyed were identified with less than 90% reported immunisation coverage and the least poor households had significantly higher odds of being vaccinated than the most poor. More than 95% of households were aware of the immunisation round and households had significantly higher odds of being vaccinated if they had prior awareness of the campaign taking place.Conclusion
Pre-campaign community education and household awareness of polio is important to increase campaign participation and subsequent immunisation coverage in South Sudan. More emphasis should be placed on ensuring immunisation is equitable according to geographic area and household socio-economic index in future rounds. We demonstrate the utility of mobile information technology for household mapping, supervision and survey activities during a national round of polio immunisation and encourage future studies to compare the effectiveness of electronic data collection and its application in polio planning and programming. 相似文献344.
Wamidh H. Talib Asma Ismail Mahmod Ayah Kamal Hasan M. Rashid Aya M. D. Alashqar Samar Khater Duaa Jamal Mostafa Waly 《Current issues in molecular biology》2021,43(2):558
Although cancer is still one of the most significant global challenges facing public health, the world still lacks complementary approaches that would significantly enhance the efficacy of standard anticancer therapies. One of the essential strategies during cancer treatment is following a healthy diet program. The ketogenic diet (KD) has recently emerged as a metabolic therapy in cancer treatment, targeting cancer cell metabolism rather than a conventional dietary approach. The ketogenic diet (KD), a high-fat and very-low-carbohydrate with adequate amounts of protein, has shown antitumor effects by reducing energy supplies to cells. This low energy supply inhibits tumor growth, explaining the ketogenic diet’s therapeutic mechanisms in cancer treatment. This review highlights the crucial mechanisms that explain the ketogenic diet’s potential antitumor effects, which probably produces an unfavorable metabolic environment for cancer cells and can be used as a promising adjuvant in cancer therapy. Studies discussed in this review provide a solid background for researchers and physicians to design new combination therapies based on KD and conventional therapies. 相似文献
345.
Samar E Makhlouf Lyman E Davis Deepika Paul Byron Anderson 《Glycoconjugate journal》1986,3(4):351-362
The (1–4)-linked oligosaccharides ofN-acetyl-d-glucosamine (GlcNAc) isolated from chitin were used to prepare synthetic immunogens and antigens by reductive amination of (GicNAc)n to bovine serum albumin (BSA). The rabbit antisera produced to the (GlcNAc)n-BSA conjugates were characterized using an enzyme-linked immunosorbent assay (ELISA) system under conditions that, only the antibodies with carbohydrate specificity were reactive with the solid-phase adsorbed (GlcNAc)n-BSA antigens. Inhibition assays using the (GlcNAc)n-BSA, (GlcNAc)n oligosaccharides, and the reduced oligosaccharides showed a relative specificity of the antisera for the chain length of the (GlcNAc)n sequences. For example, the anti-(GlcNAc)5-and anti-(GlcNAc)4-sera were inhibited best by the longer chain (GlcNAc)n ologosaccharides with the antibody combining sites directed mainly to the cyclic GlcNAc residues of the (GlcNAc)n-BSA conjugates. The antibody combining sites were in part directed to the acyclic moiety of the reducing end of the oligosaccharides as shown by the increased inhibitory activities of the reduced (GlcNAc)n oligosaccharides particularly, with the anti-(GlcNAc)2-and anti-(GlcNAc)3-sera. The best hapten inhibitors for the anti-(GlcNAc)2-BSA and anti-(GlcNAc)1-BSA sera were theN-butylamine derivatives of (GlcNAc)2 and (GlcNAc)1, respectively, indicating that the antibodies were also reactive with the secondary amine formed between the reducing end of the oligosaccharides and the -amino groups of lysine.Abbreviations ELISA
enzyme-linked immunosorbent assay
- BSA
bovine serum albumin
- GicNAc
N-acetyl-d-glucosamine
- (GlcNAc)n
Oligosaccharides containing GlcNAc in 1–4 linkages
- (GlcNAc)2
DGlcNAc(1–4)-d-GlcNAc
- (GlcNAc)3
(GlcNAc)4 and (GlcNAc)5, the homologous oligosaccharides of (GlcNAc)2
- PBS
phosphate buffered saline (0.01 M sodium phosphate, pH73 containing 0.15%M (NaCl)
- PBSA
PBS containing 1% BSA and 0.1% Tween-20
- ONPG
o-nitrophenyl--d-galactopyranoside 相似文献
346.
Sahar M. Gadelhaq Shawky M. Aboelhadid Abdel-Azeem S. Abdel-Baki Khaled M. Hassan Waleed M. Arafa Samar M. Ibrahium Saleh Al-Quraishy Ahmed O. Hassan Shams G. Abd El-Kareem 《Medical and veterinary entomology》2023,37(1):63-75
The current study was conducted to investigate the efficacy and stability of D-limonene (DL) and its nanoemulsion (DLN) against pigeon feather lice (Columbicola columbae) and their mode of action. DL pure form and DLN were prepared and characterized freshly and after storage for 50 days. In vitro bioassay on live lice was conducted with different concentrations of DL, DLN, and deltamethrin (DM). The results revealed significant mortality rates in the DL-, DLN-, DM-treated groups when compared with the control (p < 0.05). The scanning electron micrographs of lice treated with DL and DLN revealed collapsed bodies with destruction in the cuticle of the mouthparts and damaged antennae. The 50 days stored DLN showed stability in their effectiveness when compared with the freshly prepared formulation. DL and DLN caused significant inhibition (p ≤ 0.05) in acetylcholinesterase activity (AchE). Malondialdehyde level (MDA) was significantly increased while glutathione was significantly decreased in DL- and DLN-treated lice. In conclusion, DL and DLN have significant lousicidal activities. DLN showed better stability than DL after storage for 50 days. In addition, the mode of action of DL may associate with its effect on the cuticle of the lice body, inhibition of AchE, and increasing oxidative stress in the treated lice. 相似文献
347.
Novotny MV Soini HA Mechref Y 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2008,866(1-2):26-47
This review discusses the current trends in molecular profiling for the emerging systems biology applications. Historically, the methodological developments in separation science were coincident with the availability of new ionization techniques in mass spectrometry. Coupling miniaturized separation techniques with technologically-advanced MS instrumentation and the modern data processing capabilities are at the heart of current platforms for proteomics, glycomics and metabolomics. These are being featured here by the examples from quantitative proteomics, glycan mapping and metabolomic profiling of physiological fluids. 相似文献
348.
Two groups of fluconazole mucoadhesive buccal discs were prepared: (a) Fluconazole buccal discs prepared by direct compression
containing bioadhesive polymers, namely, Carbopol 974p (Cp), sodium carboxymethyl cellulose (SCMC), or sodium alginate (SALG)
in combination with hydroxypropyl methylcellulose (HPMC) or hydroxyethyl cellulose (HEC). (b) Fluconazole buccal discs prepared
by freeze drying containing different polymer combinations (SCMC/HPMC, Cp/HPMC, SALG/HPMC, and chitosan/SALG). The prepared
discs were evaluated by investigating their release pattern, swelling capacity, mucoadhesion properties, and in vitro adhesion time. In vivo evaluation of the buccal disc and in vivo residence times were also performed. Fluconazole salivary concentration after application of fluconazole buccal systems to
four healthy volunteers was determined using microbiological assay and high-performance liquid chromatography. SCMC/HPMC buccal
disc prepared by direct compression could be considered comparatively superior mucoadhesive disc regarding its in vitro adhesion time, in vivo residence time, and in vitro/in vivo release rates of the drug. Determination of the amount of drug released in saliva after application of the selected fluconazole
disc confirmed the ability of the disc to deliver the drug over a period of approximately 5 h and to reduce side effects and
possibility of drug interaction encountered during systemic therapy of fluconazole, which would be beneficial in the case
of oral candidiasis. 相似文献
349.
Daniel Villarreal Garry Reams Huma Samar Robert Spear Ronald H. Freeman 《Obesity (Silver Spring, Md.)》2004,12(6):1006-1010
Objective: Previous investigations have demonstrated that leptin promotes natriuresis with a renal tubular effect. However, the mechanisms involved in this response are unclear. The present study was designed to examine the hypothesis that the natriuretic response to leptin in normotensive Sprague‐Dawley rats is regulated by nitric oxide (NO). Research Methods and Procedures: The hemodynamic and renal excretory effects of intravenous bolus administration of pharmacological doses of synthetic murine leptin were examined in groups of control Sprague‐Dawley rats (n = 8), Sprague‐Dawley rats treated for 4 days with the NO synthase inhibitor Nω‐nitro‐l‐arginine methyl ester (l‐NAME) (n = 8), and Sprague‐Dawley rats treated for 4 days with l‐NAME followed by acute treatment with sodium nitroprusside (n = 8). Results: In the control group (n = 8), an intravenous bolus of leptin, 400 μg/kg body weight, increased urinary sodium excretion 4‐ to 6‐fold. In the Sprague‐Dawley rats chronically administered l‐NAME (n = 8), an intravenous bolus of 400 μg/kg of leptin did not increase sodium excretion. Acute sodium nitroprusside infusion to Sprague‐Dawley rats chronically treated with l‐NAME (n = 8) was associated with partial restoration of the sodium excretory response to leptin administration. Discussion: Collectively, these results are interpreted to suggest that the natriuretic and diuretic responses to leptin observed in the Sprague‐Dawley rat require a functional NO system. 相似文献
350.