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991.
Choko AT Desmond N Webb EL Chavula K Napierala-Mavedzenge S Gaydos CA Makombe SD Chunda T Squire SB French N Mwapasa V Corbett EL 《PLoS medicine》2011,8(10):e1001102
Background
Although HIV testing and counseling (HTC) uptake has increased dramatically in Africa, facility-based services are unlikely to ever meet ongoing need to the full. A major constraint in scaling up community and home-based HTC services is the unacceptability of receiving HTC from a provider known personally to prospective clients. We investigated the potential of supervised oral HIV self-testing from this perspective.Methods and Findings
Adult members of 60 households and 72 members of community peer groups in urban Blantyre, Malawi, were selected using population-weighted random cluster sampling. Participants were offered self-testing plus confirmatory HTC (parallel testing with two rapid finger-prick blood tests), standard HTC alone, or no testing. 283 (95.6%) of 298 selected adults participated, including 136 (48.0%) men. 175 (61.8%) had previously tested (19 known HIV positive), although only 64 (21.5%) within the last year. HIV prevalence was 18.5%. Among 260 (91.9%) who opted to self-test after brief demonstration and illustrated instructions, accuracy was 99.2% (two false negatives). Although 98.5% rated the test “not hard at all to do,” 10.0% made minor procedural errors, and 10.0% required extra help. Most participants indicated willingness to accept self-test kits, but not HTC, from a neighbor (acceptability 94.5% versus 46.8%, p = 0.001).Conclusions
Oral supervised self-testing was highly acceptable and accurate, although minor errors and need for supervisory support were common. This novel option has potential for high uptake at local community level if it can be supervised and safely linked to counseling and care. Please see later in the article for the Editors'' Summary 相似文献992.
993.
994.
MacPherson P Webb EL Choko AT Desmond N Chavula K Napierala Mavedzenge S Makombe SD Chunda T Squire SB Corbett EL 《PloS one》2011,6(10):e26814
Background
HIV/AIDS related stigma is a major barrier to uptake of HIV testing and counselling (HTC). We assessed the extent of stigmatising attitudes expressed by participants offered community-based HTC, and their anticipated stigma from others to assess relationship with HIV test uptake. From these data, we constructed a brief stigma scale for use around the time of HIV testing.Methods and Findings
Adult members of 60 households in urban Blantyre, Malawi, were selected using population-weighted random cluster sampling and offered HTC with the option to self-test before confirmatory HTC. Prior to HTC a 15-item HIV stigma questionnaire was administered. We used association testing and principal components analysis (PCA) to construct a scale measure of stigma. Of 226 adults invited to participate, 216 (95.6%) completed questionnaires and 198/216 (91.7%) opted to undergo HTC (all self-tested). Stigmatising attitudes were uncommon, but anticipated stigma was common, especially fearing verbal abuse (22%) or being abandoned by their partner (11%). Three questions showed little association or consistency with the remaining 12 stigma questions and were not included in the final scale. For the 12-question final scale, Cronbach''s alpha was 0.75. Level of stigma was not associated with previously having tested for HIV (p = 0.318) or agreeing to HTC (p = 0.379), but was associated with expressed worry about being or becoming HIV infected (p = 0.003).Conclusions
Anticipated stigma prior to HTC was common among both men and women. However, the high uptake of HTC suggests that this did not translate into reluctance to accept community-based testing. We constructed a brief scale to measure stigma at the time of HIV testing that could rapidly identify individuals requiring additional support following diagnosis and monitor the impact of increasing availability of community-based HTC on prevalence of stigma. 相似文献995.
Drosophila larvae change from exhibiting attraction to aversion as the concentration of salt in a substrate is increased. However, some aversive concentrations appear to act as positive reinforcers, increasing attraction to an odour with which they have been paired. We test whether this surprising dissociation between the unconditioned and conditioned response depends on the larvae's experience of salt concentration in their food. We find that although the point at which a NaCl concentration becomes aversive shifts with different rearing experience, the dissociation remains evident. Testing larvae using a substrate 0.025 M above the NaCl concentration on which the larvae were reared consistently results in aversive choice behaviour but appetitive reinforcement effects. 相似文献
996.
Amankwah EK Wang Q Schildkraut JM Tsai YY Ramus SJ Fridley BL Beesley J Johnatty SE Webb PM Chenevix-Trench G;Australian Ovarian Cancer Study Group Dale LC Lambrechts D Amant F Despierre E Vergote I Gayther SA Gentry-Maharaj A Menon U Chang-Claude J Wang-Gohrke S Anton-Culver H Ziogas A Dörk T Dürst M Antonenkova N Bogdanova N Brown R Flanagan JM Kaye SB Paul J Bützow R Nevanlinna H Campbell I Eccles DM Karlan BY Gross J Walsh C Pharoah PD Song H Krüger Kjær S Høgdall E Høgdall C Lundvall L 《PloS one》2011,6(5):e19642
Alterations in stromal tissue components can inhibit or promote epithelial
tumorigenesis. Decorin (DCN) and lumican (LUM)
show reduced stromal expression in serous epithelial ovarian cancer (sEOC). We
hypothesized that common variants in these genes associate with risk.
Associations with sEOC among Caucasians were estimated with odds ratios (OR)
among 397 cases and 920 controls in two U.S.-based studies (discovery set), 436
cases and 1,098 controls in Australia (replication set 1) and a consortium of 15
studies comprising 1,668 cases and 4,249 controls (replication set 2). The
discovery set and replication set 1 (833 cases and 2,013 controls) showed
statistically homogeneous (Pheterogeneity≥0.48) decreased risks of
sEOC at four variants: DCN rs3138165, rs13312816 and rs516115,
and LUM rs17018765 (OR = 0.6 to 0.9;
Ptrend = 0.001 to 0.03). Results from
replication set 2 were statistically homogeneous
(Pheterogeneity≥0.13) and associated with increased risks at
DCN rs3138165 and rs13312816, and LUM
rs17018765: all ORs = 1.2; Ptrend≤0.02. The
ORs at the four variants were statistically heterogeneous across all 18 studies
(Pheterogeneity≤0.03), which precluded combining. In post-hoc
analyses, interactions were observed between each variant and recruitment period
(Pinteraction≤0.003), age at diagnosis
(Pinteraction = 0.04), and year of diagnosis
(Pinteraction = 0.05) in the five studies
with available information (1,044 cases, 2,469 controls). We conclude that
variants in DCN and LUM are not directly
associated with sEOC, and that confirmation of possible effect modification of
the variants by non-genetic factors is required. 相似文献
997.
998.
Yi Kai Ng Amitha K. Hewavitharana Richard Webb P. Nicholas Shaw John A. Fuerst 《Applied microbiology and biotechnology》2013,97(7):3097-3108
The developmental cycle of the obligate marine antibiotic producer actinobacterium Salinispora arenicola isolated from a Great Barrier Reef marine sponge was investigated in relation to mycelium and spore ultrastructure, synthesis of rifamycin antibiotic compounds, and expression of genes correlated with spore formation and with rifamycin precursor synthesis. The developmental cycle of S. arenicola M413 on solid agar medium was characterized by substrate mycelium growth, change of colony color, and spore formation; spore formation occurred quite early in colony growth but development of black colonies occurred only at late stages, correlated with a change in spore maturity in relation to cell wall layers. Rifamycins were detected throughout the growth cycle, but changed in relative quantity at particular phases in the cycle, with a marked increase after 32 days. Expression of the spore division gene ssgA and the rifK gene for 3-amino-5-hydroxybenzoate synthase responsible for rifamycin precursor synthesis was seen even at early stages of the growth cycle. ssgA expression significantly increased between days 26 and 31, but rifK expression effectively remained constant throughout the growth cycle, consistent with the early synthesis of rifamycin. Factors other than precursor synthesis may be responsible for an observed late increase in rifamycin production. A useful approach for measuring and exploring the regulation of antibiotic synthesis and gene expression in the marine natural product producer S. arenicola has been established. 相似文献
999.
Jafar Hasan Hayden K. Webb Vi Khanh Truong Sergey Pogodin Vladimir A. Baulin Gregory S. Watson Jolanta A. Watson Russell J. Crawford Elena P. Ivanova 《Applied microbiology and biotechnology》2013,97(20):9257-9262
The nanopattern on the surface of Clanger cicada (Psaltoda claripennis) wings represents the first example of a new class of biomaterials that can kill bacteria on contact based solely on its physical surface structure. As such, they provide a model for the development of novel functional surfaces that possess an increased resistance to bacterial contamination and infection. Their effectiveness against a wide spectrum of bacteria, however, is yet to be established. Here, the bactericidal properties of the wings were tested against several bacterial species, possessing a range of combinations of morphology and cell wall type. The tested species were primarily pathogens, and included Bacillus subtilis, Branhamella catarrhalis, Escherichia coli, Planococcus maritimus, Pseudomonas aeruginosa, Pseudomonas fluorescens, and Staphylococcus aureus. The wings were found to consistently kill Gram-negative cells (i.e., B. catarrhalis, E. coli, P. aeruginosa, and P. fluorescens), while Gram-positive cells (B. subtilis, P. maritimus, and S. aureus) remained resistant. The morphology of the cells did not appear to play any role in determining cell susceptibility. The bactericidal activity of the wing was also found to be quite efficient; 6.1?±?1.5?×?106 P. aeruginosa cells in suspension were inactivated per square centimeter of wing surface after 30-min incubation. These findings demonstrate the potential for the development of selective bactericidal surfaces incorporating cicada wing nanopatterns into the design. 相似文献
1000.
Song Ha Nguyen Hayden K. Webb David E. Mainwaring Peter J. Mahon Russell J. Crawford 《Biofouling》2013,29(3):297-307
Aliphatic crystallites, characteristic of the eicosane and docosane components of naturally occurring lipids, were found to form microtextures that were structured by specific interactions with ordered graphite (HOPG) used as the underlying substratum, as confirmed by scanning electron microscopy (SEM) and fast Fourier transform (FFT) analysis. Confocal scanning laser microscopy (CLSM) showed highly directed bacterial alignment for two bacterial species (spherical and rod-shaped), reflecting the preferential orientation of the crystallite–air–water interfaces to give linear and triangular bacterial patterning. The mechanisms of bacterial attachment are demonstrated in terms of the balance between effective radial adhesional forces and the capillary forces resulting from the water contact angle of the bacteria at the three-phase line (TPL) of the lipid surface. It is suggested that these microtextured surfaces, which exhibit the ability to limit bacterial adhesion to a precise patterning at the lipid TPL, could be used as a means of controlling bacterial colonization. 相似文献