106 research outputs found
PMTCT from research to reality - results from a routine service
Objectives. Assessment of the efficacy of a prevention of mother-to-child transmission (PMTCT) programme in a routine service setting in comparison to a research environment.Design. Descriptive study over a 13-month period utilising retrospective data obtained from hospital records complemented by prospective data on a sample of patients enrolled in a study to determine an affordable HIV diagnostic protocol for infants.Setting. Routine PMTCT service at Coronation Women and Children's Hospital (CWCH) situated in Johannesburg and affiliated to the University of the Witwatersrand.Subjects. Pregnant women known to be HIV infected who delivered at CWCH from 1 October 2001 to 31 October 2002.Outcome measures. The HIV transmission rate to infants, which reflects nevirapine (NVP) delivery and infant feeding practices, and follow-up rates of perinatally exposed children.Results. Of the 8 221 deliveries, 1 234 (15%) occurred in women known to be HIV infected, HIV transmission rates of 8.7% at 6 weeks and 8.9% at 3 months of age in the study population verifies the high rate of NVP administration and the ability of women to formula-feed their babies and abstain from breast-feeding. More than one-third of infants never return for follow-up and more than 70% are lost to follow-up by 4 months of age.Conclusions. The low HIV transmission rate confirms the efficacy of this routine service PMTCT programme. HIV infected children are not being identified for medical management as part of PMTCT follow-up. It is imperativethat record keeping is improved to facilitate ongoing monitoring
Afforestation Effects on Soil Carbon Storage in the United States: A Synthesis
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/152514/1/saj2sssaj20120236.pd
Leveraging the Road to Health booklet as a unique patient identifier to monitor the prevention of mother-to-child transmission programme
BACKGROUND. Currently there is no unique patient identification system in the South African public health sector. Therefore, routine
laboratory data cannot effectively be de-duplicated, thereby hampering surveillance of laboratory-diagnosed diseases such as mother-tochild
transmission of HIV.
OBJECTIVES. To determine the uptake of Road to Health booklet (RTHB) identifiers at HIV polymerase chain reaction (PCR) birth test and
describe their performance in linking follow-up test results in the early infant diagnosis programme.
METHODS. Between May 2016 and May 2017, Tshwane District Clinical Services implemented a unique patient identifier pilot project
in which a sticker-page of unique, readable, barcoded patient identifiers was incorporated in the patient-retained immunisation record
(the RTHB) before distribution. Uptake of RTHB identifiers at birth was calculated as the proportion of HIV PCR tests in infants aged <6 days
registered with an RTHB identifier over the total number of registered HIV PCR tests. Descriptive analysis of demographic details was
performed among infants with two registered HIV PCR tests linked by the RTHB identifier, and performance of the National Health
Laboratory Service Corporate Data Warehouse (NHLS CDW)-linking algorithm in matching RTHB-linked results was calculated using a
2 Ă 2 table.
RESULTS. A total of 5 309 HIV PCR birth tests registered with an RTHB identifier were extracted from the NHLS CDW over the 13-month
period of the pilot project. The number of registered RTHB identifiers increased from 24 (2% of birth PCR tests) in May 2016, peaking at
728 (56% of birth PCR tests) in May 2017. Among infants with a registered RTHB identifier at birth, 635 (12%) had a subsequent linked HIV
PCR test, as indicated by the same RTHB number registered for a later specimen. Demographic details at the time of birth and subsequent
PCR test were compared, demonstrating that <4% of infants had exact matches for name, surname, date of birth and sex; 74% of birth tests
had variations such as âborn toâ or âbaby of â in place of a first name; surnames matched exactly in 61% of cases; 18% (n=116) of infants had
both tests performed at the same facility, of which only 27% (n=31) had the same patient folder number on both test results.
CONCLUSIONS. Leveraging RTHBs as unique patient identifiers, even if used temporarily until linkage to other future national unique
identifiers, promises to be an effective scalable approach to laboratory-based surveillance, facilitating healthcare provider access to all test
results from birth.AHM acknowledges support from the Discovery Foundation
(ref. no. 034203).http://www.samj.org.zaam2018Medical VirologyPaediatrics and Child Healt
Quality and turnaround times of viral load monitoring under prevention of mother-to-child transmission of HIV Option B+ in six South African districts with a high antenatal HIV burden
BACKGROUND : Barriers to monitoring maternal HIV viral load (VL) and achieving 90% viral suppression during pregnancy and breastfeeding
still need to be understood in South Africa (SA).
OBJECTIVES : To measure quality of VL care and turnaround times (TATs) for returning VL results to women enrolled in the prevention of
mother-to-child transmission of HIV (PMTCT) programme in primary healthcare facilities.
METHODS : Data were obtained from a 2018 cross-sectional evaluation of the PMTCT Option B+ programme in six SA districts with high
antenatal and infant HIV prevalence. Quality of VL care was measured as the proportion of clients reporting that results were explained to
them. TATs for VL results were calculated using dates abstracted from four to five randomly selected facility-based client records to report
overall facility âshort TATâ (â„80% of records with TAT â€7 days). Logistical regression and logit-based risk difference statistics were used.
RESULTS : Achieving overall short TAT was uncommon. Only 50% of facilities in one rural district, zero in one urban metro district and
9 - 38% in other districts had short TAT. The significant difference between districts was influenced by the duration of keeping results
in facilities after receipt from the laboratory. Expected quality of VL care received ranged between 66% and 85%. Client-related factors
significantly associated with low quality of care, observed in two urban districts and one rural district, included lower education, recent
initiation of antiretroviral treatment and experiencing barriers to clinic visits. Experiencing clinic visit barriers was also negatively associated
with short TATs.
CONCLUSIONS : We demonstrate above-average quality of care and delayed return of results to PMTCT clients. Context-specific interventions
are needed to shorten TATs.The Presidentâs Emergency Plan for AIDS Relief (PEPFAR) through the Centers for Disease Control and Prevention (CDC). The publication of this manuscript was funded by the South African Medical Research Council.http://www.samj.org.zadm2022Paediatrics and Child Healt
A role for XRCC2 gene polymorphisms in breast cancer risk and survival
Background
The XRCC2 gene is a key mediator in the homologous recombination repair of DNA double strand breaks. It is hypothesised that inherited variants in the XRCC2 gene might also affect susceptibility to, and survival from, breast cancer.
Methods
The study genotyped 12 XRCC2 tagging single nucleotide polymorphisms (SNPs) in 1131 breast cancer cases and 1148 controls from the Sheffield Breast Cancer Study (SBCS), and examined their associations with breast cancer risk and survival by estimating ORs and HRs, and their corresponding 95% CIs. Positive findings were further investigated in 860 cases and 869 controls from the Utah Breast Cancer Study (UBCS) and jointly analysed together with available published data for breast cancer risk. The survival findings were further confirmed in studies (8074 cases) from the Breast Cancer Association Consortium (BCAC).
Results
The most significant association with breast cancer risk in the SBCS dataset was the XRCC2 rs3218408 SNP (recessive model p=2.3Ă10â4, minor allele frequency (MAF)=0.23). This SNP yielded an ORrec of 1.64 (95% CI 1.25 to 2.16) in a two-site analysis of SBCS and UBCS, and a meta-ORrec of 1.33 (95% CI 1.12 to 1.57) when all published data were included. This SNP may mark a rare risk haplotype carried by two in 1000 of the control population. Furthermore, the XRCC2 coding R188H SNP (rs3218536, MAF=0.08) was significantly associated with poor survival, with an increased per-allele HR of 1.58 (95% CI 1.01 to 2.49) in a multivariate analysis. This effect was still evident in a pooled meta-analysis of 8781 breast cancer patients from the BCAC (HR 1.19, 95% CI 1.05 to 1.36; p=0.01).
Conclusions
These findings suggest that XRCC2 SNPs may influence breast cancer risk and survival
Heterogeneity of luminal breast cancer characterised by immunohistochemical expression of basal markers
Background: Luminal A breast cancer defined as hormone receptor positive and human epidermal growth factor receptor 2 (HER2) negative is known to be heterogeneous. Previous study showed that luminal A tumours with the expression of basal markers ((cytokeratin (CK) 5 or CK5/6) or epidermal growth factor receptor (EGFR)) were associated with poorer prognosis compared with those that stained negative for basal markers. Prompted by this study, we assessed whether tumour characteristics and risk factors differed by basal marker status within luminal A tumours.
Methods: We pooled 5040 luminal A cases defined by immunohistochemistry (4490 basal-negative ((CK5 (or CK5/6))â and EGFRâ) and 550 basal-positive ((CK5 (or CK5/6+)) or EGFR+)) from eight studies participating in the Breast Cancer Association Consortium. Caseâcase comparison was performed using unconditional logistic regression.
Results: Tumour characteristics and risk factors did not vary significantly by the expression of basal markers, although results suggested that basal-positive luminal tumours tended to be smaller and node negative, and were more common in women with a positive family history and lower body mass index.
Conclusions: Most established breast cancer risk factors were similar in basal-positive and basal-negative luminal A tumours. The non-significant but suggestive differences in tumour features and family history warrant further investigations
Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in âs = 7 TeV pp collisions with the ATLAS detector
A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fbâ1 of protonâproton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results
Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC
Measurements of inclusive jet suppression in heavy ion collisions at the LHC
provide direct sensitivity to the physics of jet quenching. In a sample of
lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated
luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with
a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the
transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the
anti-kt algorithm with values for the distance parameter that determines the
nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of
the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp.
Jet production is found to be suppressed by approximately a factor of two in
the 10% most central collisions relative to peripheral collisions. Rcp varies
smoothly with centrality as characterized by the number of participating
nucleons. The observed suppression is only weakly dependent on jet radius and
transverse momentum. These results provide the first direct measurement of
inclusive jet suppression in heavy ion collisions and complement previous
measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables,
submitted to Physics Letters B. All figures including auxiliary figures are
available at
http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02
Measurement of the cross section for isolated-photon plus jet production in pp collisions at âs=13 TeV using the ATLAS detector
The dynamics of isolated-photon production in association with a jet in protonâproton collisions at a centre-of-mass energy of 13 TeV are studied with the ATLAS detector at the LHC using a dataset with an integrated luminosity of 3.2 fbâ1. Photons are required to have transverse energies above 125 GeV. Jets are identified using the anti- algorithm with radius parameter and required to have transverse momenta above 100 GeV. Measurements of isolated-photon plus jet cross sections are presented as functions of the leading-photon transverse energy, the leading-jet transverse momentum, the azimuthal angular separation between the photon and the jet, the photonâjet invariant mass and the scattering angle in the photonâjet centre-of-mass system. Tree-level plus parton-shower predictions from Sherpa and Pythia as well as next-to-leading-order QCD predictions from Jetphox and Sherpa are compared to the measurements
Measurement of W± and Z-boson production cross sections in pp collisions at âs=13 TeV with the ATLAS detector
See paper for full list of authors - 17 pages plus author list + cover pages (34 pages total), 5 figures, 3 tables, submitted to Phys. Lett. B, All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2015-03/International audienceMeasurements of the and production cross sections (where ) in proton-proton collisions at TeV are presented using data recorded by the ATLAS experiment at the Large Hadron Collider, corresponding to a total integrated luminosity of 81 pb. The total inclusive -boson production cross sections times the single-lepton-flavour branching ratios are nb and nb for and , respectively. The total inclusive -boson production cross section times leptonic branching ratio, within the invariant mass window GeV, is nb. The , , and -boson production cross sections and cross-section ratios within a fiducial region defined by the detector acceptance are also measured. The cross-section ratios benefit from significant cancellation of experimental uncertainties, resulting in and . Theoretical predictions, based on calculations accurate to next-to-next-to-leading order for quantum chromodynamics and next-to-leading order for electroweak processes and which employ different parton distribution function sets, are compared to these measurements
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