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Find video protocols related to scientific articles indexed in Pubmed.
Impact of systematic HIV testing on case finding and retention in care at a primary care clinic in South Africa.
Trop. Med. Int. Health
PUBLISHED: 09-22-2014
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Systematic, opt-out HIV counselling and testing (HCT) may diagnose individuals at lower levels of immunodeficiency but may impact loss to follow-up (LTFU) if healthier people are less motivated to engage and remain in HIV care. We explored LTFU and patient clinical outcomes under two different HIV testing strategies.
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Hyperpolarized and Inert Gas MRI: The Future.
Mol Imaging Biol
PUBLISHED: 09-18-2014
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Magnetic resonance imaging (MRI) is a potentially ideal imaging modality for noninvasive, nonionizing, and longitudinal assessment of disease. Hyperpolarized (HP) agents have been developed in the past 20 years for MR imaging, and they have the potential to vastly improve MRI sensitivity for the diagnosis and management of various diseases. The polarization of nuclear magnetic resonance (NMR)-sensitive nuclei other than (1)H (e.g., (3)He, (129)Xe) can be enhanced by a factor of up to 100,000 times above thermal equilibrium levels, which enables direct detection of the HP agent with no background signal. In this review, a number of HP media applications in MR imaging are discussed, including HP (3)He and (129)Xe lung imaging, HP (129)Xe brain imaging, and HP (129)Xe biosensors. Inert fluorinated gas MRI, which is a new lung imaging technique that does not require hyperpolarization, is also briefly discussed. This technique will likely be an important future direction for the HP gas lung imaging community.
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Revisiting pneumonia and exposure status in infants born to HIV-infected mothers.
Pediatr. Infect. Dis. J.
PUBLISHED: 09-03-2014
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HIV-exposed uninfected infants are an increasing population. Past analyses have often categorized these infants as uninfected leading to inaccurate conclusions. We present a HIV exposure, rather than infection, based reanalysis of treatment failure among children with pneumonia to show that failure odds among HIV-exposed uninfected infants are intermediate between their unexposed and infected counterparts. Additional prospective studies aimed at better understanding this population are needed.
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Mortality in patients with HIV-1 infection starting antiretroviral therapy in South Africa, Europe, or North America: a collaborative analysis of prospective studies.
PLoS Med.
PUBLISHED: 09-01-2014
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High early mortality in patients with HIV-1 starting antiretroviral therapy (ART) in sub-Saharan Africa, compared to Europe and North America, is well documented. Longer-term comparisons between settings have been limited by poor ascertainment of mortality in high burden African settings. This study aimed to compare mortality up to four years on ART between South Africa, Europe, and North America.
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Anatomical, functional and metabolic imaging of radiation-induced lung injury using hyperpolarized MRI.
NMR Biomed
PUBLISHED: 08-25-2014
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MRI of hyperpolarized (129) Xe gas and (13) C-enriched substrates (e.g. pyruvate) presents an unprecedented opportunity to map anatomical, functional and metabolic changes associated with lung injury. In particular, inhaled hyperpolarized (129) Xe gas is exquisitely sensitive to changes in alveolar microanatomy and function accompanying lung inflammation through decreases in the apparent diffusion coefficient (ADC) of alveolar gas and increases in the transfer time (Ttr ) of xenon exchange from the gas and into the dissolved phase in the lung. Furthermore, metabolic changes associated with hypoxia arising from lung injury may be reflected by increases in lactate-to-pyruvate signal ratio obtained by magnetic resonance spectroscopic imaging following injection of hyperpolarized [1-(13) C]pyruvate. In this work, the application of hyperpolarized (129) Xe and (13) C MRI to radiation-induced lung injury (RILI) is reviewed and results of ADC, Ttr and lactate-to-pyruvate signal ratio changes in a rat model of RILI are summarized. These results are consistent with conventional functional (i.e. blood gases) and histological (i.e. tissue density) changes, and correlate significantly with inflammatory cell counts (i.e. macrophages). Hyperpolarized MRI may provide an earlier indication of lung injury associated with radiotherapy of thoracic tumors, potentially allowing adjustment of treatment before the onset of severe complications and irreversible fibrosis. Copyright © 2014 John Wiley & Sons, Ltd.
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In vivo regional ventilation mapping using fluorinated gas MRI with an x-centric FGRE method.
Magn Reson Med
PUBLISHED: 08-08-2014
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Inert fluorinated gas lung MRI is a new and promising alternative to hyperpolarized gas lung MRI; it is less expensive and does not require expensive isotopes/polarizers. The thermally polarized nature of signal obtained from fluorinated gases makes it relatively easy to use for dynamic lung imaging and for obtaining lung ventilation maps. In this study, we propose that the sensitivity and resolution of fluorine-19 ((19) F) in vivo images can be improved using the x-centric pulse sequence, thereby achieving a short echo time/pulse repetition time. This study is a transitional step for converting to more sustainable gases for lung imaging.
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Good practices for quantitative bias analysis.
Int J Epidemiol
PUBLISHED: 08-01-2014
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Quantitative bias analysis serves several objectives in epidemiological research. First, it provides a quantitative estimate of the direction, magnitude and uncertainty arising from systematic errors. Second, the acts of identifying sources of systematic error, writing down models to quantify them, assigning values to the bias parameters and interpreting the results combat the human tendency towards overconfidence in research results, syntheses and critiques and the inferences that rest upon them. Finally, by suggesting aspects that dominate uncertainty in a particular research result or topic area, bias analysis can guide efficient allocation of sparse research resources. The fundamental methods of bias analyses have been known for decades, and there have been calls for more widespread use for nearly as long. There was a time when some believed that bias analyses were rarely undertaken because the methods were not widely known and because automated computing tools were not readily available to implement the methods. These shortcomings have been largely resolved. We must, therefore, contemplate other barriers to implementation. One possibility is that practitioners avoid the analyses because they lack confidence in the practice of bias analysis. The purpose of this paper is therefore to describe what we view as good practices for applying quantitative bias analysis to epidemiological data, directed towards those familiar with the methods. We focus on answering questions often posed to those of us who advocate incorporation of bias analysis methods into teaching and research. These include the following. When is bias analysis practical and productive? How does one select the biases that ought to be addressed? How does one select a method to model biases? How does one assign values to the parameters of a bias model? How does one present and interpret a bias analysis?. We hope that our guide to good practices for conducting and presenting bias analyses will encourage more widespread use of bias analysis to estimate the potential magnitude and direction of biases, as well as the uncertainty in estimates potentially influenced by the biases.
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Detection of radiation induced lung injury in rats using dynamic hyperpolarized (129)Xe magnetic resonance spectroscopy.
Med Phys
PUBLISHED: 07-04-2014
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Radiation induced lung injury (RILI) is a common side effect for patients undergoing thoracic radiation therapy (RT). RILI can lead to temporary or permanent loss of lung function and in extreme cases, death. Combining functional lung imaging information with conventional radiation treatment plans may lead to more desirable treatment plans that reduce lung toxicity and improve the quality of life for lung cancer survivors. Magnetic Resonance Imaging of the lung following inhalation of hyperpolarized(129)Xe may provide a useful nonionizing approach for probing changes in lung function and structure associated with RILI before, during, or after RT (early and late time-points).
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Mortality among adults transferred and lost to follow-up from antiretroviral therapy programmes in South Africa: a multicenter cohort study.
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 07-01-2014
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Little is known about outcomes after transfer out (TFO) and loss to follow-up (LTF) and how differential outcomes might bias mortality estimates, as analyses generally censor or exclude TFOs/LTF. Using data linked to the National Population Register, we explored mortality among TFO and LTF patients compared with patients who were retained and investigated how linkage impacted on mortality estimates.
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T2* relaxometry of fetal brain at 1.5 Tesla using a motion tolerant method.
Magn Reson Med
PUBLISHED: 03-29-2014
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The aim of this study was to determine T2* values for the fetal brain in utero and to compare them with previously reported values in preterm and term neonates. Knowledge of T2* may be useful for assessing brain development, brain abnormalities, and for optimizing functional imaging studies.
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Incidence and predictors of herpes zoster among antiretroviral therapy-naïve patients initiating HIV treatment in Johannesburg, South Africa.
Int. J. Infect. Dis.
PUBLISHED: 03-25-2014
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To describe the characteristics of HIV-infected patients experiencing herpes zoster after antiretroviral therapy (ART) initiation and to describe the incidence and predictors of a herpes zoster diagnosis.
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Kaposi's Sarcoma in HIV-infected patients in South Africa: Multicohort study in the antiretroviral therapy era.
Int. J. Cancer
PUBLISHED: 03-07-2014
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The incidence of Kaposi's Sarcoma (KS) is high in South Africa but the impact of antiretroviral therapy (ART) is not well defined. We examined incidence and survival of KS in HIV-infected patients enrolled in South African ART programs. We analyzed data of three ART programs: Khayelitsha township and Tygerberg Hospital programs in Cape Town and Themba Lethu program in Johannesburg. We included patients aged >16 years. ART was defined as a regimen of at least three drugs. We estimated incidence rates of KS for patients on ART and not on ART. We calculated Cox models adjusted for age, sex and time-updated CD4 cell counts and HIV-1 RNA. A total of 18,254 patients (median age 34.5 years, 64% female, median CD4 cell count at enrolment 105 cells/?L) were included. During 37,488 person-years follow-up 162 patients developed KS. The incidence was 1,682/100,000 person-years (95% confidence interval [CI] 1,406-2,011) among patients not receiving ART and 138/100,000 person-years (95% CI 102-187) among patients on ART. The adjusted hazard ratio comparing time on ART with time not on ART was 0.19 (95% CI 0.13-0.28). Low CD4 cell counts (time-updated) and male sex were also associated with KS. Estimated survival of KS patients at one year was 72.2% (95% CI 64.9-80.2) and higher in men than in women. The incidence of KS is substantially lower on ART than not on ART. Timely initiation of ART is essential to prevent KS and KS-associated morbidity and mortality in South Africa and other regions in Africa with a high burden of HIV.
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Impact of choice of NRTI in first-line antiretroviral therapy: a cohort analysis of stavudine vs. tenofovir.
Trop. Med. Int. Health
PUBLISHED: 03-03-2014
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In April 2010, South Africa replaced stavudine with tenofovir in first-line antiretroviral therapy (ART) despite tenofovir's higher cost. We examined treatment outcomes over 24 months amongst patients initiated on tenofovir-based vs. stavudine-based first-line regimens.
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Inert fluorinated gas MRI: a new pulmonary imaging modality.
NMR Biomed
PUBLISHED: 02-10-2014
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Fluorine-19 ((19) F) MRI of the lungs using inhaled inert fluorinated gases can potentially provide high quality images of the lungs that are similar in quality to those from hyperpolarized (HP) noble gas MRI. Inert fluorinated gases have the advantages of being nontoxic, abundant, and inexpensive compared with HP gases. Due to the high gyromagnetic ratio of (19) F, there is sufficient thermally polarized signal for imaging, and averaging within a single breath-hold is possible due to short longitudinal relaxation times. Therefore, the gases do not need to be hyperpolarized prior to their use in MRI. This eliminates the need for an expensive polarizer and expensive isotopes. Inert fluorinated gas MRI of the lungs has been previously demonstrated in animals, and more recently in healthy volunteers and patients with lung diseases. The ongoing improvements in image quality demonstrate the potential of (19) F MRI for visualizing the distribution of ventilation in human lungs and detecting functional biomarkers. In this brief review, the development of inert fluorinated gas MRI, current progress, and future prospects are discussed. The current state of HP noble gas MRI is also briefly discussed in order to provide context to the development of this new imaging modality. Overall, this may be a viable clinical imaging modality that can provide useful information for the diagnosis and management of chronic respiratory diseases. Copyright © 2014 John Wiley & Sons, Ltd.
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Resting State fMRI in the moving fetus: a robust framework for motion, bias field and spin history correction.
Neuroimage
PUBLISHED: 01-15-2014
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There is growing interest in exploring fetal functional brain development, particularly with Resting State fMRI. However, during a typical fMRI acquisition, the womb moves due to maternal respiration and the fetus may perform large-scale and unpredictable movements. Conventional fMRI processing pipelines, which assume that brain movements are infrequent or at least small, are not suitable. Previous published studies have tackled this problem by adopting conventional methods and discarding as much as 40% or more of the acquired data. In this work, we developed and tested a processing framework for fetal Resting State fMRI, capable of correcting gross motion. The method comprises bias field and spin history corrections in the scanner frame of reference, combined with slice to volume registration and scattered data interpolation to place all data into a consistent anatomical space. The aim is to recover an ordered set of samples suitable for further analysis using standard tools such as Group Independent Component Analysis (Group ICA). We have tested the approach using simulations and in vivo data acquired at 1.5 T. After full motion correction, Group ICA performed on a population of 8 fetuses extracted 20 networks, 6 of which were identified as matching those previously observed in preterm babies.
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Immunodeficiency at the start of combination antiretroviral therapy in low-, middle-, and high-income countries.
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 01-15-2014
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To describe the CD4 cell count at the start of combination antiretroviral therapy (cART) in low-income (LIC), lower middle-income (LMIC), upper middle-income (UMIC), and high-income (HIC) countries.
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The relation between efavirenz versus nevirapine and virologic failure in Johannesburg, South Africa.
J Int AIDS Soc
PUBLISHED: 01-01-2014
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Previous research has raised concerns that patients given nevirapine (NVP)-based regimens experience more virologic failure than patients given efavirenz (EFV)-based regimens. We investigated this hypothesis in a cohort of HIV-positive patients at a large HIV treatment clinic in South Africa.
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Attrition through Multiple Stages of Pre-Treatment and ART HIV Care in South Africa.
PLoS ONE
PUBLISHED: 01-01-2014
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While momentum for increasing treatment thresholds is growing, if patients cannot be retained in HIV care from the time of testing positive through long-term adherence to antiretroviral therapy (ART), such strategies may fall short of expected gains. While estimates of retention on ART exist, few cohorts have data on retention from testing positive through long-term ART care.
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CD4 criteria improves the sensitivity of a clinical algorithm developed to identify viral failure in HIV-positive patients on antiretroviral therapy.
J Int AIDS Soc
PUBLISHED: 01-01-2014
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Several studies from resource-limited settings have demonstrated that clinical and immunologic criteria are poor predictors of virologic failure, confirming the need for viral load monitoring or at least an algorithm to target viral load testing. We used data from an electronic patient management system to develop an algorithm to identify patients at risk of viral failure using a combination of accessible and inexpensive markers.
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Poor CD4 recovery and risk of subsequent progression to AIDS or death despite viral suppression in a South African cohort.
J Int AIDS Soc
PUBLISHED: 01-01-2014
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The prognostic role of CD4 response in the first six months of treatment in patients achieving early viral suppression during HIV treatment is unclear.
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Voice recognition is here comma like it or not period.
Indian J Radiol Imaging
PUBLISHED: 12-19-2013
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Voice recognition (VR) technology needs improvement, but is as integral to the current practice of radiology as Radiology Information Systems and Picture Archival and Communication Systems. In the 1990s, the radiology community gave VR technology a rather lukewarm reception, but since then it has emerged as the predominant method of radiology reporting in the United States. In this article, we examine how VR technology works, outline the positive and negative aspects of VR technology on work flow, identify common VR transcription errors and review the discussion on VR adoption in the recent literature. We add to the discussion our personal experiences in an international teleradiology group.
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Tenofovir or zidovudine in second-line antiretroviral therapy after stavudine failure in southern Africa.
Antivir. Ther. (Lond.)
PUBLISHED: 11-04-2013
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There is debate over using tenofovir or zidovudine alongside lamivudine in second-line antiretroviral therapy (ART) following stavudine failure. We analyzed outcomes in cohorts from South Africa, Zambia and Zimbabwe METHODS: Patients aged ?16 years who switched from a first-line regimen including stavudine to a ritonavir-boosted lopinavir-based second-line regimen with lamivudine or emtricitabine and zidovudine or tenofovir in seven ART programs in southern Africa were included. We estimated the causal effect of receiving tenofovir or zidovudine on mortality and virological failure using Cox proportional hazards marginal structural models. Its parameters were estimated using inverse probability of treatment weights. Baseline characteristics were age, sex, calendar year and country. CD4 cell count, creatinine and hemoglobin levels were included as time-dependent confounders.
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Pulmonary Ultrashort Echo Time (19)F MR Imaging with Inhaled Fluorinated Gas Mixtures in Healthy Volunteers: Feasibility.
Radiology
PUBLISHED: 10-28-2013
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Purpose To perform static breath-hold fluorine 19 ((19)F) three-dimensional (3D) ultrashort echo time (UTE) magnetic resonance (MR) imaging of the lungs in healthy volunteers by using a mixture of 79% perfluoropropane (PFP) and 21% O2. Materials and Methods This study protocol was approved by the local research ethics board and by Health Canada. All volunteers provided written informed consent. Ten healthy volunteers underwent MR imaging at 3.0 T. Fluorine 19 3D UTE MR images were acquired during a 15-second breath hold according to one of two breathing protocols: protocol A, a 1-L inhalation of a mixture of 79% PFP and 21% O2, and protocol B, continuous breathing from a 5-L bag of a mixture of 79% PFP and 21% O2 followed by a 1-L inhalation of the same PFP-O2 mixture from a separate bag and a subsequent breath hold. The signal-to-noise ratio (SNR) was measured in the three most central image sections and was compared between breathing protocols by using an unpaired t test. Results Overall, the SNR was significantly greater for breathing protocol B (continuous breathing) than for breathing protocol A (single breath) (P = .018). The mean SNRs were 18 ± 6 (standard deviation) and 32 ± 6 for images acquired by using breathing protocols A and B, respectively. Breathing protocol B improves SNR by "washing out" the air from the lungs and increasing the PFP concentration prior to (19)F imaging. Conclusion This study demonstrates the feasibility of (19)F 3D UTE static breath-hold MR imaging of human lungs with inert fluorinated gases. © RSNA, 2013.
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Malignant melanoma arising in the setting of epidermolysis bullosa simplex: an important distinction from epidermolysis bullosa nevus.
JAMA Dermatol
PUBLISHED: 08-23-2013
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Patients with epidermolysis bullosa (EB) do not carry a significantly increased risk of melanoma but are prone to developing large, markedly atypical melanocytic nevi (EB nevi), which may mimic melanoma clinically and histologically. Many authors now favor a conservative approach in managing atypical pigmented lesions in patients with EB.
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Initiating antiretroviral therapy when presenting with higher CD4 cell counts results in reduced loss to follow-up in a resource-limited setting.
AIDS
PUBLISHED: 08-22-2013
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In August 2011, South Africa expanded its adult antiretroviral therapy (ART) guidelines to allow treatment initiation at CD4 cell values 350?cells/?l or less. Mortality and morbidity are known to be reduced when initiating at higher CD4 levels; we explored the impact on patient loss to follow-up.
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Rates and cost of hospitalization before and after initiation of antiretroviral therapy in urban and rural settings in South Africa.
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 08-21-2013
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Few studies have compared hospitalizations before and after antiretroviral therapy (ART) initiation in the same patients. We analyzed the cost of hospitalizations among 3906 adult patients in 2 South African hospitals, 30% of whom initiated ART. Hospitalizations were 50% and 40% more frequent and 1.5 and 2.6 times more costly at a CD4 cell count, 100 cells/mm(3) when compared with 200–350 cells/mm(3) in the pre-ART and ART period, respectively. Mean inpatient cost per patient year was USD 117 (95%confidence interval, 85 to 158) for patients on ART and USD 72(95% confidence interval, 56 to 89) for pre-ART patients. Raising ART eligibility thresholds could avoid the high cost of hospitalization before and immediately after ART initiation.
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The feasibility of using screening criteria to reduce clinic visits for stable patients on antiretroviral therapy in South Africa.
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 08-21-2013
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South African HIV care providers are exploring ways to reduce the intensity of patient visits while maintaining high quality of care. We used routinely collected data to model whether a simple screening tool could identify stable patients who would not need to see a doctor during a scheduled medical visit.
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Acute hemorrhagic leukoencephalopathy associated with influenza A (H1N1) virus.
Neurocrit Care
PUBLISHED: 08-15-2013
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Acute hemorrhagic leukoencephalopathy (AHLE) is a rare condition associated with H1N1. In this condition the infection triggers an autoimmune response which results in perivascular demyelination and hemorrhage in the brain parenchyma.
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Increases in regimen durability associated with the introduction of tenofovir at a large public-sector clinic in Johannesburg, South Africa.
J Int AIDS Soc
PUBLISHED: 07-04-2013
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Introduction: In April 2010, tenofovir replaced stavudine in public-sector first-line antiretroviral therapy (ART) in South Africa. The association of tenofovir with fewer side effects and toxicities compared to stavudine could translate to increased durability of tenofovir-based regimens. We evaluated changes over time in regimen durability at the Themba Lethu Clinic, Johannesburg, South Africa. Methods: This was a cohort analysis of treatment-naïve, non-pregnant adult patients initiated on ART between April 2004 and December 2011. First-line ART regimens before April 2010 consisted of stavudine or zidovudine with lamivudine and either efavirenz or nevirapine. Tenofovir was substituted for stavudine after April 2010. We evaluated the frequency and type of single-drug substitutions (excluding switches to second-line therapy). Cox models were used to evaluate the association of ART initiation year and antiretroviral drug type with single-drug substitutions in the first 12 months on treatment. Results: One thousand nine hundred and sixty-four (10%) substitutions occurred amongst 19,699 patients. Excluding 2004 (year of treatment roll-out), before 2010 one-year single-drug substitutions ranged from 10.0 to 13.1%. In 2011, well after integration of tenofovir, substitutions decreased to 5.6%. Single-drug substitution was lowest amongst patients on tenofovir (5.1%) versus zidovudine (11.3%), 30 mg stavudine (10.5%) or 40 mg stavudine (14.4%). Adjusted Cox models showed that patients initiating treatment between 2005 and 2010 (vs. 2011) had a twofold increased hazard of single-drug substitution, while those on zidovudine or stavudine had a two to threefold increase in single-drug substitution versus tenofovir patients in the first 12 months on ART. Conclusions: The decline in single-drug substitutions is associated with the introduction of tenofovir. Tenofovir use could improve regimen durability and treatment outcomes in resource-limited settings.
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Antiretroviral therapy, labor productivity, and sex: a longitudinal cohort study of tea pluckers in Kenya.
AIDS
PUBLISHED: 06-19-2013
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To estimate the impact of antiretroviral therapy (ART) on labor productivity and income using detailed employment data from two large tea plantations in western Kenya for HIV-infected tea pluckers who initiated ART.
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Effect of home based HIV counselling and testing intervention in rural South Africa: cluster randomised trial.
BMJ
PUBLISHED: 06-15-2013
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To assess the effect of home based HIV counselling and testing on the prevalence of HIV testing and reported behavioural changes in a rural subdistrict of South Africa.
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Kaposi sarcoma-associated herpes virus and response to antiretroviral therapy: a prospective study of HIV-infected adults.
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 04-26-2013
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The possible impact of coinfection with the Kaposi sarcoma-associated herpes virus (KSHV) on the response to antiretroviral therapy (ART) is unknown. Prospective studies are rare, particularly in Africa.
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Multidimensional analysis of fetal posterior fossa in health and disease.
Cerebellum
PUBLISHED: 04-05-2013
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Fetal magnetic resonance imaging (MRI) is now routinely used to further investigate cerebellar malformations detected with ultrasound. However, the lack of 2D and 3D biometrics in the current literature hinders the detailed characterisation and classification of cerebellar anomalies. The main objectives of this fetal neuroimaging study were to provide normal posterior fossa growth trajectories during the second and third trimesters of pregnancy via semi-automatic segmentation of reconstructed fetal brain MR images and to assess common cerebellar malformations in comparison with the reference data. Using a 1.5-T MRI scanner, 143 MR images were obtained from 79 normal control and 53 fetuses with posterior fossa abnormalities that were grouped according to the severity of diagnosis on visual MRI inspections. All quantifications were performed on volumetric datasets, and supplemental outcome information was collected from the surviving infants. Normal growth trajectories of total brain, cerebellar, vermis, pons and fourth ventricle volumes showed significant correlations with 2D measurements and increased in second-order polynomial trends across gestation (Pearson r, p?
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Same-Day CD4 Testing to Improve Uptake of HIV Care and Treatment in South Africa: Point-of-Care Is Not Enough.
AIDS Res Treat
PUBLISHED: 04-04-2013
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Background. We evaluated whether a pilot program providing point-of-care (POC), but not rapid, CD4 testing (BD FACSCount) immediately after testing HIV-positive improved retention in care. Methods. We conducted a retrospective record review at the Themba Lethu Clinic in Johannesburg, South Africa. We compared all walk-in patients testing HIV-positive during February, July 2010 (pilot POC period) to patients testing positive during January 2008-February 2009 (baseline period). The outcome for those with a ?250 cells/mm(3) when testing HIV-positive was initiating ART <16 weeks after HIV testing. Results. 771 patients had CD4 results from the day of HIV testing (421 pilots, 350 baselines). ART initiation within 16 weeks was 49% in the pilot period and 46% in the baseline period. While all 421 patients during the pilot period should have been offered the POC test, patient records indicate that only 73% of them were actually offered it, and among these patients only 63% accepted the offer. Conclusions. Offering CD4 testing using a point-of-care, but not rapid, technology and without other health system changes had minor impacts on the uptake of HIV care and treatment. Point-of-care technologies alone may not be enough to improve linkage to care and treatment after HIV testing.
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Stem cell factor expression in B cell malignancies is influenced by the niche.
Leuk. Lymphoma
PUBLISHED: 04-02-2013
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Our group has previously demonstrated that expression of the cytokine stem cell factor (SCF) by leukemic blasts is a frequent finding in pre-B acute lymphoblastic leukemia (ALL). Whether SCF expression is a feature of other B cell malignancies and whether cross-talk from the local microenvironment modulates malignant cell SCF production are, however, unknown. Here we show using immunohistochemistry that SCF is expressed by a wide variety of indolent and aggressive B cell malignancies involving the bone marrow (BM) or lymph nodes (LNs). In diseases such as follicular lymphoma (FL), however, where lymphoma cells uniquely associate with the BM endosteal niche, BM lymphoma does not express SCF, while LN involvement is SCF positive. In contrast, cases of FL with high-grade transformation in the BM are SCF positive. These data suggest that lymphoma cell interaction with the endosteal niche inhibits SCF production, and that FL cells become independent of this microenvironment effect following transformation.
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Life expectancies of South African adults starting antiretroviral treatment: collaborative analysis of cohort studies.
PLoS Med.
PUBLISHED: 04-01-2013
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Few estimates exist of the life expectancy of HIV-positive adults receiving antiretroviral treatment (ART) in low- and middle-income countries. We aimed to estimate the life expectancy of patients starting ART in South Africa and compare it with that of HIV-negative adults.
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Patient retention from HIV diagnosis through one year on antiretroviral therapy at a primary health care clinic in Johannesburg, South Africa.
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 03-09-2013
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To compare patient retention at 3 stages of pre-antiretroviral (ART) care and 2 stages of post-ART care to identify when greatest attrition occurs.
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Management options for metastatic melanoma in the era of novel therapies: a primer for the practicing dermatologist: part II: Management of stage IV disease.
J. Am. Acad. Dermatol.
PUBLISHED: 02-28-2013
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Part II of this continuing medical education article will discuss the treatment options for stage IV melanoma, including novel therapies, such as ipilimumab and vemurafenib; established therapies, including high-dose interleukin-2, conventional chemotherapy, and biochemotherapy; and additional therapies currently under investigation in the form of clinical trials. The approach to patients with brain metastases will be discussed, as will recommendations for distress screening and defining aspects of palliative care.
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Management options for metastatic melanoma in the era of novel therapies: a primer for the practicing dermatologist: part I: Management of stage III disease.
J. Am. Acad. Dermatol.
PUBLISHED: 02-28-2013
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The incidence of melanoma has increased for decades, and while surgical treatment of early stage disease is often curative, metastatic disease continues to carry a significantly less promising outlook with high associated health burden and economic cost. An expanding number of dermatologists are playing a key role in coordinating the care of patients with melanoma, including in an increasingly important role among multidisciplinary melanoma clinics, many of which are anchored in dermatology departments. Advances in the understanding of the genetic and immunoregulatory aspects of melanoma development and progression have yielded a wave of novel therapeutics that has made significant impact on the approach to patients with metastatic disease. Frequently updated management guidelines and unfamiliarity with approved adjuvant treatment options, including interferon, clinical trials, or radiation therapy, can pose a challenge for dermatologists seeking to effectively coordinate the care of and establish proper expectations for patients with stage III disease. Moreover, greater awareness of treatment modalities for in-transit disease may allow dermatologists to play a more active role in the treatment of these patients and to expand their ability to explain and coordinate options, such as limb perfusion or infusion. Part I of this continuing medical education article will use clinical scenarios to outline the current management options for patients with stage III melanoma, including both adjuvant treatment options for resected stage III disease and primary treatment options for in-transit metastases. Part II of this series will address stage IV disease.
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The interplay between CD4 cell count, viral load suppression and duration of antiretroviral therapy on mortality in a resource-limited setting.
Trop. Med. Int. Health
PUBLISHED: 02-18-2013
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To examine the interaction between CD4 cell count, viral load suppression and duration of antiretroviral therapy (ART) on mortality.
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Loss to follow-up before and after delivery among women testing HIV positive during pregnancy in Johannesburg, South Africa.
Trop. Med. Int. Health
PUBLISHED: 02-03-2013
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HIV-positive pregnant women are at heightened risk of becoming lost to follow-up (LTFU) from HIV care. We examined LTFU before and after delivery among pregnant women newly diagnosed with HIV.
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CD4 count slope and mortality in HIV-infected patients on antiretroviral therapy: multicohort analysis from South Africa.
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 01-25-2013
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In many resource-limited settings monitoring of combination antiretroviral therapy (cART) is based on the current CD4 count, with limited access to HIV RNA tests or laboratory diagnostics. We examined whether the CD4 count slope over 6 months could provide additional prognostic information.
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Cough aerosols of Mycobacterium tuberculosis predict new infection: a household contact study.
Am. J. Respir. Crit. Care Med.
PUBLISHED: 01-12-2013
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Airborne transmission of Mycobacterium tuberculosis results from incompletely characterized host, bacterial, and environmental factors. Sputum smear microscopy is associated with considerable variability in transmission.
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Comparison of hyperpolarized (3) He and (129) Xe MRI for the measurement of absolute ventilated lung volume in rats.
Magn Reson Med
PUBLISHED: 01-03-2013
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PURPOSE: MRI using hyperpolarized noble gases, (3) He and (129) Xe, provides noninvasive assessments of lung structure and function. Previous work demonstrated that absolute ventilated lung volumes (aVLV) measured in rats using hyperpolarized (3) He agree well with micro-CT. METHODS: In this work, aVLV measurements were performed in rats using hyperpolarized (129) Xe MRI and compared with hyperpolarized (3) He measurements of aVLV under matched ventilation conditions. Whole-lung compliance was also determined. Partial volume, apparent diffusion coefficient, and effective transverse relaxation time corrections were applied during postprocessing to reduce bias between methods. RESULTS: Mean apparent diffusion coefficient of the trachea was 0.83?±?0.09 cm(2) /s and 0.067?±?0.011 cm(2) /s for (3) He and (129) Xe, respectively. Mean apparent diffusion coefficient of parenchyma was 0.21?±?0.07 cm(2) /s and 0.027?±?0.008 cm(2) /s for (3) He and (129) Xe, respectively. Mean transverse relaxation time values were 1.57?±?0.25 ms and 2.80?±?0.25 ms for (3) He and (129) Xe, respectively, in a model trachea and 3.18?±?1.00 ms and 4.88?±?0.60 ms for (3) He and (129) Xe, respectively, for lung parenchyma. Mean aVLV values were 7.07?±?0.67 mL and 6.99?±?1.00 mL at 14 cmH2 O and 4.88?±?0.71 mL and 5.36?±?0.76 mL at 10 cmH2 O obtained with (3) He and (129) Xe, respectively, demonstrating good agreement between (129) Xe and (3) He. CONCLUSIONS: (129) Xe offers an important alternative to (3) He for hyperpolarized gas MRI of aVLV in rats. Magn Reson Med, 2013. © 2013 Wiley Periodicals, Inc.
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The impact of choice of NNRTI on short-term treatment outcomes among HIV-infected patients prescribed tenofovir and lamivudine in Johannesburg, South Africa.
PLoS ONE
PUBLISHED: 01-01-2013
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Recent WHO guidelines for resource-limited settings recommend tenofovir in first-line antiretroviral therapy (ART) yet there are suggestions that patients receiving nevirapine with tenofovir have worse outcomes than those receiving efavirenz. We sought to compare outcomes among those taking nevirapine vs. efavirenz with tenofovir and lamivudine.
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A novel approach to accounting for loss to follow-up when estimating the relationship between CD4 Count at ART initiation and mortality.
PLoS ONE
PUBLISHED: 01-01-2013
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While CD4 strongly predicts mortality on antiretroviral therapy (ART), estimates from programmatic data suffer from incomplete patient outcomes.
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Treatment response and mortality among patients starting antiretroviral therapy with and without Kaposi sarcoma: a cohort study.
PLoS ONE
PUBLISHED: 01-01-2013
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Improved survival among HIV-infected individuals on antiretroviral therapy (ART) has focused attention on AIDS-related cancers including Kaposi sarcoma (KS). However, the effect of KS on response to ART is not well-described in Southern Africa. We assessed the effect of KS on survival and immunologic and virologic treatment responses at 6- and 12-months after initiation of ART.
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Community case management of severe pneumonia with oral amoxicillin in children aged 2-59 months in Haripur district, Pakistan: a cluster randomised trial.
Lancet
PUBLISHED: 11-10-2011
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First dose oral co-trimoxazole and referral are recommended for WHO-defined severe pneumonia. Difficulties with referral compliance are reported in many low-resource settings, resulting in low access to appropriate treatment. The objective in this study was to assess whether community case management by lady health workers (LHWs) with oral amoxicillin in children with severe pneumonia was equivalent to current standard of care.
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Outcomes of stable HIV-positive patients down-referred from a doctor-managed antiretroviral therapy clinic to a nurse-managed primary health clinic for monitoring and treatment.
AIDS
PUBLISHED: 10-15-2011
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To compare clinical, immunologic and virologic outcomes among stable HIV-positive patients down-referred to a nurse-managed primary healthcare clinic (PHC) for treatment maintenance to those who remained at a doctor-managed treatment-initiation site.
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Poorer ART outcomes with increasing age at a large public sector HIV clinic in Johannesburg, South Africa.
J Int Assoc Physicians AIDS Care (Chic)
PUBLISHED: 09-27-2011
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As the current HIV-positive population ages, the absolute number of patients >50 years on treatment is increasing.
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Prevalence and predictors of kaposi sarcoma herpes virus seropositivity: a cross-sectional analysis of HIV-infected adults initiating ART in Johannesburg, South Africa.
Infect. Agents Cancer
PUBLISHED: 08-03-2011
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Kaposi sarcoma (KS) is the most common AIDS-defining tumour in HIV-infected individuals in Africa. Kaposi sarcoma herpes virus (KSHV) infection precedes development of KS. KSHV co-infection may be associated with worse outcomes in HIV disease and elevated KSHV viral load may be an early marker for advanced HIV disease among untreated patients. We examined the prevalence of KSHV among adults initiating antiretroviral therapy (ART) and compared immunological, demographic and clinical factors between patients seropositive and seronegative for KSHV.
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Outcomes of antiretroviral treatment in programmes with and without routine viral load monitoring in Southern Africa.
AIDS
PUBLISHED: 06-18-2011
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To compare outcomes of antiretroviral therapy (ART) in South Africa, where viral load monitoring is routine, with those in Malawi and Zambia, where monitoring is based on CD4 cell counts.
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Relationship between renal dysfunction, nephrotoxicity and death among HIV adults on tenofovir.
AIDS
PUBLISHED: 06-08-2011
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In April 2010, the South African government added tenofovir disoproxil fumarate to its first-line antiretroviral therapy (ART) for HIV patients. We analyzed the relationship between renal dysfunction at tenofovir initiation, nephrotoxicity and mortality.
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Low rates of nucleoside reverse transcriptase inhibitor resistance in a well-monitored cohort in South Africa on antiretroviral therapy.
Antivir. Ther. (Lond.)
PUBLISHED: 05-29-2011
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The emergence of complex HIV-1 drug resistance mutations has been linked to the duration of time patients are on a failing antiretroviral drug regimen. This study reports on resistance profiles in a closely monitored subtype C infected cohort.
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The net cost of incorporating resistance testing into HIV/AIDS treatment in South Africa: a Markov model with primary data.
J Int AIDS Soc
PUBLISHED: 05-15-2011
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Current guidelines for providing antiretroviral therapy (ART) in South Africas public sector programme call for switching patients from first-line to second-line treatment upon virologic failure as indicated by two consecutive viral loads above 5000 copies/ml, but without laboratory evidence of viral resistance. We modelled the net cost of adding resistance testing for patients with virological failure and retaining patients without resistance on first-line therapy, rather than switching all failures to second-line therapy.
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Outpatient treatment of children with severe pneumonia with oral amoxicillin in four countries: the MASS study.
Trop. Med. Int. Health
PUBLISHED: 05-04-2011
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A recent randomized clinical trial demonstrated home-based treatment of WHO-defined severe pneumonia with oral amoxicillin was equivalent to hospital-based therapy and parenteral antibiotics. We aimed to determine whether this finding is generalizable across four countries.
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Effect of training traditional birth attendants on neonatal mortality (Lufwanyama Neonatal Survival Project): randomised controlled study.
BMJ
PUBLISHED: 02-05-2011
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To determine whether training traditional birth attendants to manage several common perinatal conditions could reduce neonatal mortality in the setting of a resource poor country with limited access to healthcare.
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Correcting mortality for loss to follow-up: a nomogram applied to antiretroviral treatment programmes in sub-Saharan Africa.
PLoS Med.
PUBLISHED: 01-18-2011
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The World Health Organization estimates that in sub-Saharan Africa about 4 million HIV-infected patients had started antiretroviral therapy (ART) by the end of 2008. Loss of patients to follow-up and care is an important problem for treatment programmes in this region. As mortality is high in these patients compared to patients remaining in care, ART programmes with high rates of loss to follow-up may substantially underestimate mortality of all patients starting ART.
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Treatment outcomes and cost-effectiveness of shifting management of stable ART patients to nurses in South Africa: an observational cohort.
PLoS Med.
PUBLISHED: 01-14-2011
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To address human resource and infrastructure shortages, resource-constrained countries are being encouraged to shift HIV care to lesser trained care providers and lower level health care facilities. This study evaluated the cost-effectiveness of down-referring stable antiretroviral therapy (ART) patients from a doctor-managed, hospital-based ART clinic to a nurse-managed primary health care facility in Johannesburg, South Africa.
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Retention in HIV care between testing and treatment in sub-Saharan Africa: a systematic review.
PLoS Med.
PUBLISHED: 01-13-2011
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Improving the outcomes of HIV/AIDS treatment programs in resource-limited settings requires successful linkage of patients testing positive for HIV to pre-antiretroviral therapy (ART) care and retention in pre-ART care until ART initiation. We conducted a systematic review of pre-ART retention in care in Africa.
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The importance of clinic attendance in the first six months on antiretroviral treatment: a retrospective analysis at a large public sector HIV clinic in South Africa.
J Int AIDS Soc
PUBLISHED: 08-11-2010
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Adherence to care and treatment are essential for HIV-infected individuals to benefit from antiretroviral therapy (ART). We sought to quantify the effects on treatment outcomes of missing visits soon after initiating ART.
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Temporal changes in programme outcomes among adult patients initiating antiretroviral therapy across South Africa, 2002-2007.
AIDS
PUBLISHED: 08-05-2010
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Little is known about the temporal impact of the rapid scale-up of large antiretroviral therapy (ART) services on programme outcomes. We describe patient outcomes [mortality, loss-to-follow-up (LTFU) and retention] over time in a network of South African ART cohorts.
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Initiating patients on antiretroviral therapy at CD4 cell counts above 200 cells/microl is associated with improved treatment outcomes in South Africa.
AIDS
PUBLISHED: 07-09-2010
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To compare treatment outcomes by starting CD4 cell counts using data from the Comprehensive International Program of Research on AIDS-South Africa trial.
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Measurement of alveolar oxygen partial pressure in the rat lung using Carr-Purcell-Meiboom-Gill spin-spin relaxation times of hyperpolarized 3He and 129Xe at 74 mT.
Magn Reson Med
PUBLISHED: 07-02-2010
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Regional measurement of alveolar oxygen partial pressure can be obtained from the relaxation rates of hyperpolarized noble gases, (3) He and (129) Xe, in the lungs. Recently, it has been demonstrated that measurements of alveolar oxygen partial pressure can be obtained using the spin-spin relaxation rate (R(2) ) of (3) He at low magnetic field strengths (<0.1 T) in vivo. R(2) measurements can be achieved efficiently using the Carr-Purcell-Meiboom-Gill pulse sequence. In this work, alveolar oxygen partial pressure measurements based on Carr-Purcell-Meiboom-Gill R(2) values of hyperpolarized (3) He and (129) Xe in vitro and in vivo in the rat lung at low magnetic field strength (74 mT) are presented. In vitro spin-spin relaxivity constants for (3) He and (129) Xe were determined to be (5.2 ± 0.6) × 10(-6) Pa(-1) sec(-1) and (7.3 ± 0.4) × 10(-6) Pa(-1) s(-1) compared with spin-lattice relaxivity constants of (4.0 ± 0.4) × 10(-6) Pa(-1) s(-1) and (4.3 ± 1.3) × 10(-6) Pa(-1) s(-1), respectively. In vivo experimental measurements of alveolar oxygen partial pressure using (3) He in whole rat lung show good agreement (r(2) = 0.973) with predictions based on lung volumes and ventilation parameters. For (129) Xe, multicomponent relaxation was observed with one component exhibiting an increase in R(2) with decreasing alveolar oxygen partial pressure.
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Early loss to follow up after enrolment in pre-ART care at a large public clinic in Johannesburg, South Africa.
Trop. Med. Int. Health
PUBLISHED: 07-01-2010
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To estimate loss to follow up (LTFU) between initial enrollment and the first scheduled return medical visit of a pre-antiretroviral therapy (ART) care program for patients not eligible for ART.
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Patient retention in antiretroviral therapy programs up to three years on treatment in sub-Saharan Africa, 2007-2009: systematic review.
Trop. Med. Int. Health
PUBLISHED: 07-01-2010
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To estimate the proportion of all-cause adult patient attrition from antiretroviral therapy (ART) programs in service delivery settings in sub-Saharan Africa through 36 months on treatment.
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Nurse versus doctor management of HIV-infected patients receiving antiretroviral therapy (CIPRA-SA): a randomised non-inferiority trial.
Lancet
PUBLISHED: 06-19-2010
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Expanded access to combination antiretroviral therapy (ART) in resource-poor settings is dependent on task shifting from doctors to other health-care providers. We compared outcomes of nurse versus doctor management of ART care for HIV-infected patients.
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Synthesis and structure of Na+-intercalated WO3(4,4-bipyridyl)0.5.
Chem. Commun. (Camb.)
PUBLISHED: 06-16-2010
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WO3(4,4-bipyridyl)0.5 was doped with Na+ by ion implantation so as to alter the electronic structure. Single-crystal X-ray diffraction reveals layers of corner-shared WO5N octahedra linked by bipyridine. In the observed space group of Pbca, the fully-ordered bipyridyls form cages with Na+ disordered bimodally about the cage centre.
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Economic outcomes of patients receiving antiretroviral therapy for HIV/AIDS in South Africa are sustained through three years on treatment.
PLoS ONE
PUBLISHED: 05-21-2010
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Although the medical outcomes of antiretroviral therapy (ART) for HIV/AIDS are well described, less is known about how ART affects patients economic activities and quality of life, especially after the first year on ART. We assessed symptom prevalence, general health, ability to perform normal activities, and employment status among adult antiretroviral therapy patients in South Africa over three full years following ART initiation.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.