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31.
Ingrid Eshun-Wilson Ajibola A. Awotiwon Ashley Germann Sophia A. Amankwaa Nathan Ford Sheree Schwartz Stefan Baral Elvin H. Geng 《PLoS medicine》2021,18(5)
BackgroundAntiretroviral therapy (ART) initiation in the community and outside of a traditional health facility has the potential to improve linkage to ART, decongest health facilities, and minimize structural barriers to attending HIV services among people living with HIV (PLWH). We conducted a systematic review and meta-analysis to determine the effect of offering ART initiation in the community on HIV treatment outcomes.Methods and findingsWe searched databases between 1 January 2013 and 22 February 2021 to identify randomized controlled trials (RCTs) and observational studies that compared offering ART initiation in a community setting to offering ART initiation in a traditional health facility or alternative community setting. We assessed risk of bias, reporting of implementation outcomes, and real-world relevance and used Mantel–Haenszel methods to generate pooled risk ratios (RRs) and risk differences (RDs) with 95% confidence intervals. We evaluated heterogeneity qualitatively and quantitatively and used GRADE to evaluate overall evidence certainty. Searches yielded 4,035 records, resulting in 8 included studies—4 RCTs and 4 observational studies—conducted in Lesotho, South Africa, Nigeria, Uganda, Malawi, Tanzania, and Haiti—a total of 11,196 PLWH. Five studies were conducted in general HIV populations, 2 in key populations, and 1 in adolescents. Community ART initiation strategies included community-based HIV testing coupled with ART initiation at home or at community venues; 5 studies maintained ART refills in the community, and 4 provided refills at the health facility. All studies were pragmatic, but in most cases provided additional resources. Few studies reported on implementation outcomes. All studies showed higher ART uptake in community initiation arms compared to facility initiation and refill arms (standard of care) (RR 1.73, 95% CI 1.22 to 2.45; RD 30%, 95% CI 10% to 50%; 5 studies). Retention (RR 1.43, 95% CI 1.32 to 1.54; RD 19%, 95% CI 11% to 28%; 4 studies) and viral suppression (RR 1.31, 95% CI 1.15 to 1.49; RD 15%, 95% CI 10% to 21%; 3 studies) at 12 months were also higher in the community-based ART initiation arms. Improved uptake, retention, and viral suppression with community ART initiation were seen across population subgroups—including men, adolescents, and key populations. One study reported no difference in retention and viral suppression at 2 years. There were limited data on adherence and mortality. Social harms and adverse events appeared to be minimal and similar between community ART initiation and standard of care. One study compared ART refill strategies following community ART initiation (community versus facility refills) and found no difference in viral suppression (RD −7%, 95% CI −19% to 6%) or retention at 12 months (RD −12%, 95% CI −23% to 0.3%). This systematic review was limited by few studies for inclusion, poor-quality observational data, and short-term outcomes.ConclusionsBased on data from a limited set of studies, community ART initiation appears to result in higher ART uptake, retention, and viral suppression at 1 year compared to facility-based ART initiation. Implementation on a wider scale necessitates broader exploration of costs, logistics, and acceptability by providers and PLWH to ensure that these effects are reproducible when delivered at scale, in different contexts, and over time.Ingrid Eshun-Wilson and co-workers assess the available evidence on community-based treatment initiation for people with HIV. 相似文献
32.
Right- and left-handed (Z) helical conformations of the hairpin d(C-G)5T4(C-G)5 monomer and dimer 总被引:7,自引:0,他引:7
The partial self-complementary 24-mer oligodeoxynucleotide d(C-G)5T4(C-G)5 forms a hairpin which can be enzymatically dimerized to a dumbbell structure. The blunt-ended nature of the hairpin is indicated by its ability to inhibit the T4 DNA ligase catalyzed joining of phi X174 HaeIII fragments. The hairpin monomer and dimer (dumbbell) undergo a reversible B to Z transition as shown by ultraviolet, circular dichroism, and 31P NMR spectroscopy. The Z form of the hairpin monomer and dimer is supported by monovalent ions (Na+), divalent ions (Mg2+ but not Mn2+), and dehydrating (ethanol) conditions. The conformational transition of d(C-G)5T4(C-G)5 monomer requires higher ionic or dehydrating conditions than those necessary for the corresponding linear oligomer d(C-G)5. The contribution of the loop (-T4-) of the hairpin to the apparent free energy change for the B to Z conformational transition at the midpoint was calculated to be 3.8 kJ mol-1. 相似文献
33.
The solution structures of two alternating purine-pyrimidine octamers, [d(G-T-A-C-G-T-A-C)]2 and the reverse sequence [d(C-A-T-G-C-A-T-G)]2, are investigated by using nuclear magnetic resonance spectroscopy and restrained molecular dynamics calculations. Chemical shift assignments are obtained for non-exchangeable protons by a combination of two-dimensional correlation and nuclear Overhauser enhancement (NOE) spectroscopy experiments. Distances between protons are estimated by extrapolating distances derived from time-dependent NOE measurements to zero mixing time. Approximate dihedral angles are determined within the deoxyribose ring from coupling constants observed in one and two-dimensional spectra. Sets of distance and dihedral determinations for each of the duplexes form the bases for structure determination. Molecular dynamics is then used to generate structures that satisfy the experimental restraints incorporated as effective potentials into the total energy. Separate runs start from classical A and B-form DNA and converge to essentially identical structures. To circumvent the problems of spin diffusion and differential motion associated with distance measurements within molecules, models are improved by NOE-based refinement in which observed NOE intensities are compared to those calculated using a full matrix analysis procedure. The refined structures generally have the global features of B-type DNA. Some, but not all, variations in dihedral angles and in the spatial relationships of adjacent base-pairs are observed to be in synchrony with the alternating purine-pyrimidine sequence. 相似文献
34.
Wiesawa Rudnicka Magorzata Kaczmarek Jacek Szeliga Tieno Germann Marzena Wickowska Barbara Ralska 《Microbiology and immunology》1997,41(11):847-853
Several genes involved in the determination of Listeria monocytogenes pathogenesis have been identified. Among them, plcA gene encodes phosphatidylinositol-specific phospholipase C (PI-PLC), plcB gene encodes a broad-range phospholipase C (PC-PLC), and actA encodes a protein contributing to actin assembly in infected cells. The interaction of L. monocytogenes wild type (LO 28) strain and two derivative mutants, plcA? (BUG 206) and actA?/plcB? (LUT 12), with macrophages and T lymphocytes was investigated in a mouse model of listeriosis. Both mutants showed evidence of attenuation. The plcA? mutant, but not the plcB? mutant, expressed an increase in susceptibility to the anti-listerial activity of macrophages. Both mutants showed a decreased ability to induce IL-12 production by bone marrow macrophages when co-stimulated with E. coli LPS or IFN-γ. In vivo, L. monocytogenes plcA? mutant was found to be a more effective stimulator of T cells than the wild LO 28 strain. 相似文献
35.
NM Kouyoumdzian NL Rukavina Mikusic G Cao MR Choi SL Della Penna BE Fernández 《Biotechnic & histochemistry》2016,91(8):510-521
We studied the effects of tempol, an oxygen radical scavenger, on hydrosaline balance in rats with acute sodium overload. Male rats with free access to water were injected with isotonic (control group) or hypertonic saline solution (0.80 mol/l NaCl) either alone (Na group) or with tempol (Na-T group). Hydrosaline balance was determined during a 90 min experimental period. Protein expressions of aquaporin 1 (AQP1), aquaporin 2 (AQP2), angiotensin II (Ang II) and endothelial nitric oxide synthase (eNOS) were measured in renal tissue. Water intake, creatinine clearance, diuresis and natriuresis increased in the Na group. Under conditions of sodium overload, tempol increased plasma sodium and protein levels and increased diuresis, natriuresis and sodium excretion. Tempol also decreased water intake without affecting creatinine clearance. AQP1 and eNOS were increased and Ang II decreased in the renal cortex of the Na group, whereas AQP2 was increased in the renal medulla. Nonglycosylated AQP1 and eNOS were increased further in the renal cortex of the Na-T group, whereas AQP2 was decreased in the renal medulla and was localized mainly in the cell membrane. Moreover, p47-phox immunostaining was increased in the hypothalamus of Na group, and this increase was prevented by tempol. Our findings suggest that tempol causes hypernatremia after acute sodium overload by inhibiting the thirst mechanism and facilitating diuresis, despite increasing renal eNOS expression and natriuresis. 相似文献
36.
Jér?me Maury Susanne M. Germann Simo Abdessamad Baallal Jacobsen Niels B. Jensen Kanchana R. Kildegaard Markus J. Herrg?rd Konstantin Schneider Anna Koza Jochen Forster Jens Nielsen Irina Borodina 《PloS one》2016,11(3)
Saccharomyces cerevisiae is widely used in the biotechnology industry for production of ethanol, recombinant proteins, food ingredients and other chemicals. In order to generate highly producing and stable strains, genome integration of genes encoding metabolic pathway enzymes is the preferred option. However, integration of pathway genes in single or few copies, especially those encoding rate-controlling steps, is often not sufficient to sustain high metabolic fluxes. By exploiting the sequence diversity in the long terminal repeats (LTR) of Ty retrotransposons, we developed a new set of integrative vectors, EasyCloneMulti, that enables multiple and simultaneous integration of genes in S. cerevisiae. By creating vector backbones that combine consensus sequences that aim at targeting subsets of Ty sequences and a quickly degrading selective marker, integrations at multiple genomic loci and a range of expression levels were obtained, as assessed with the green fluorescent protein (GFP) reporter system. The EasyCloneMulti vector set was applied to balance the expression of the rate-controlling step in the β-alanine pathway for biosynthesis of 3-hydroxypropionic acid (3HP). The best 3HP producing clone, with 5.45 g.L-1 of 3HP, produced 11 times more 3HP than the lowest producing clone, which demonstrates the capability of EasyCloneMulti vectors to impact metabolic pathway enzyme activity. 相似文献
37.
Adenosine cyclic 3',5'-monophosphate uptake and regulation of membrane protein kinase in intact human erythrocytes 总被引:1,自引:0,他引:1
The uptake of adenosine cyclic 3',5'-monophosphate (cAMP) and stimulation of membrane-associated protein kinase in mature human erythrocytes were investigated. cAMP transport across the membrane was temperature dependent, and cAMP binding to the isolated membrane had less temperature dependence. More than 99% of the [3H]-cAMP taken up by erythrocytes was nonmembrane bound. Maximal stimulation of membrane protein kinase and maximal occupancy of membrane cAMP binding sites by extracellular cAMP cccurred at 30 degrees C within 30 min after initiation of the incubation of erythrocytes with cAMP. The concentration of extracellular cAMP that gave half-maximal stimulation of membrane protein kinase was 5.4 X 10-4 M, a value consistent with the concentrations of cAMP (5.2 X 10-4 M) found to occupy half-maximally the membrane cAMP binding sites in erythrocytes. Extracellular cAMP and to a lesser extent guanosine cyclic 3',5'-monophosphate and inosine cyclic 3',5'-monophosphate stimulated membrane protein kinase in erythrocytes. The cAMP uptake by human erythrocytes as well as cAMP binding to membranes in the erythrocyte was blocked by an inhibitor [4,4'-bis(isothiocyano)stilbene-2,2-disulfonate] of the anion channel. These studies indicate that cAMP can be transported across membranes into human erythrocytes and can bind to membranes to activate membrane protein kinase. It appears that there is a shared transport channel for cAMP and anion transport. 相似文献
38.
39.
Zhang X Germann S Blus BJ Khorasanizadeh S Gaudin V Jacobsen SE 《Nature structural & molecular biology》2007,14(9):869-871
Polycomb proteins are required for maintenance of silent chromatin states via histone H3 Lys27 trimethylation (H3K27me3) in animals, but homologs are not found in plant genomes. Using a DamID-chip method, we found that the Arabidopsis thaliana chromodomain-containing protein LHP1 colocalizes with H3K27me3 genome-wide. The LHP1 chromodomain also binds H3K27me3 with high affinity, suggesting that LHP1 has functions similar to those of Polycomb. 相似文献