JoVE Visualize What is visualize?
Stop Reading. Start Watching.
Advanced Search
Stop Reading. Start Watching.
Regular Search
Find video protocols related to scientific articles indexed in Pubmed.
Prospective cross-sectional evaluation of the small membrane filtration method for diagnosis of pulmonary tuberculosis.
J. Clin. Microbiol.
PUBLISHED: 05-07-2014
Show Abstract
Hide Abstract
Smear microscopy has suboptimal sensitivity, and there is a need to improve its performance since it is commonly used to diagnose tuberculosis (TB). We prospectively evaluated the diagnostic accuracy of the small membrane filtration (SMF) method, an approach that uses a vacuum manifold and is designed to concentrate bacilli onto a filter that can be examined microscopically. We enrolled hospitalized adults suspected to have pulmonary TB in Kampala, Uganda. We obtained a clinical history and three spontaneously expectorated sputum specimens for smear microscopy (direct, concentrated, and SMF), MGIT (mycobacterial growth indicator tube) 960 and Lowenstein-Jensen (LJ) cultures, and Xpert MTB/RIF testing. We performed per-specimen (primary) and per-patient analyses. From October 2012 to June 2013, we enrolled 212 patients (579 sputum specimens). The participants were mostly female (63.2%), and 81.6% were HIV infected; their median CD4 cell count was 47 cells/?l. Overall, 19.0%, 20.4%, 27.1%, 25.2%, and 25.9% of specimens tested positive by direct smear, concentrated smear, MGIT culture, LJ culture, and Xpert test, respectively. In the per-specimen analysis, the sensitivity of the SMF method (48.5%; 95% confidence interval [CI], 37.4 to 59.6) was lower than those of direct smear (60.9%; 51.4 to 70.5 [P = 0.0001]) and concentrated smear (63.3%; 53.6 to 73.1 [P < 0.0001]). Subgroup analyses showed that SMF performed poorly in specimens having a low volume or low bacterial load. The SMF method performed poorly compared to standard smear techniques and was sensitive to sample preparation techniques. The optimal laboratory SMF protocol may require striking a fine balance between sample dilution and filtration failure rate.
Related JoVE Video
Diagnostic accuracy of a rapid urine lipoarabinomannan test for tuberculosis in HIV-infected adults.
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 03-29-2014
Show Abstract
Hide Abstract
In settings of high HIV prevalence, tuberculosis control and patient management are hindered by lack of accurate, rapid tuberculosis diagnostic tests that can be performed at point-of-care. The Determine TB LAM Ag (TB LAM) test is a lateral flow immunochromatographic test for detection of mycobacterial lipoarabinomannan (LAM) in urine. Our objective was to determine sensitivity and specificity of the TB LAM test for tuberculosis diagnosis.
Related JoVE Video
Comparative performance of urinary lipoarabinomannan assays and Xpert MTB/RIF in HIV-infected individuals.
AIDS
PUBLISHED: 03-19-2014
Show Abstract
Hide Abstract
Xpert MTB/RIF ('Xpert') and urinary lipoarabinomannan (LAM) assays offer rapid tuberculosis (TB) diagnosis, but have suboptimal sensitivity when used individually in HIV-positive patients. The yield of these tests used in combination for the diagnosis of active TB among HIV-infected TB suspects is unknown.
Related JoVE Video
Clinical utility of a novel molecular assay in various combination strategies with existing methods for diagnosis of HIV-related tuberculosis in Uganda.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Low income, high-tuberculosis burden, countries are considering selective deployment of Xpert MTB/RIF assay (Xpert) due to high cost per test. We compared the diagnostic gain of the Xpert add-on strategy with Xpert replacement strategy for pulmonary tuberculosis diagnosis among HIV-infected adults to inform its implementation.
Related JoVE Video
Point-of-care lateral flow assays for tuberculosis and cryptococcal antigenuria predict death in HIV infected adults in Uganda.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Mortality in hospitalized, febrile patients in Sub-Saharan Africa is high due to HIV-infected, severely immunosuppressed patients with opportunistic co-infection, particularly disseminated tuberculosis (TB) and cryptococcal disease. We sought to determine if a positive lateral flow assay (LFA) result for urine lipoarabinomannan (LAM) and cryptococcal antigenuria was associated with mortality.
Related JoVE Video
Importance of cough and M. tuberculosis strain type as risks for increased transmission within households.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
The degree to which tuberculosis (TB) is transmitted between persons is variable. Identifying the factors that contribute to transmission could provide new opportunities for TB control. Transmission is influenced by host, bacterial and environmental factors. However, distinguishing their individual effects is problematic because measures of disease severity are tightly correlated, and assessing the virulence of Mycobacterium tuberculosis isolates is complicated by epidemiological and clinical confounders.
Related JoVE Video
Discordance of tuberculin skin test and interferon gamma release assay in recently exposed household contacts of pulmonary TB cases in Brazil.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
Interferon-gamma (IFN-?) release assays (IGRAs) such as the Quantiferon Gold In-tube test are in vitro assays that measure IFN-? release from T cells in response to M. tuberculosis (Mtb)-specific antigens. Unlike the tuberculin skin test (TST), IGRA is specific and able to distinguish Mtb-infection from BCG vaccination. In this study we evaluated the concordance between TST and IGRA and the efficacy of IGRA in diagnosing new Mtb infection in household contacts (HHC) of pulmonary tuberculosis (PTB) cases. A total of 357 HHC of TB cases in Vitória, Brazil were studied. A TST was performed within 2 weeks following enrollment of the HHC and if negative a second TST was performed at 8-12 weeks. HHC were categorized as initially TST positive (TST+), persistently TST negative (TST-), or TST converters (TSTc), the latter representative of new infection. IGRA was performed at 8-12 weeks following enrollment and the test results were positive in 82% of TST+, 48% of TSTc, and 12% of TST-, indicating poor concordance between the two test results among HHC in each category. Evaluating CXCL10 levels in a subset of IGRA supernatants or lowering the IGRA cutoff value to define a positive test increased agreement between TST and IGRA test results. However, ROC curves demonstrated that this resulted in a trade-off between sensitivity and specificity of IGRA with respect to TST. Together, the findings suggest that until the basis for the discordance between TST and IGRA is fully understood, it may be necessary to utilize both tests to diagnose new Mtb infection in recently exposed HHC. Operationally, in IGRA negative HHC, it may be useful to employ a lower cutoff value for IGRA to allow closer monitoring for potential conversion.
Related JoVE Video
Treatment outcomes of new tuberculosis patients hospitalized in Kampala, Uganda: a prospective cohort study.
PLoS ONE
PUBLISHED: 01-01-2014
Show Abstract
Hide Abstract
In most resource limited settings, new tuberculosis (TB) patients are usually treated as outpatients. We sought to investigate the reasons for hospitalisation and the predictors of poor treatment outcomes and mortality in a cohort of hospitalized new TB patients in Kampala, Uganda.
Related JoVE Video
Sensititre MYCOTB MIC Plate for Testing Mycobacterium tuberculosis Susceptibility to First- and Second-Line Drugs.
Antimicrob. Agents Chemother.
PUBLISHED: 10-07-2013
Show Abstract
Hide Abstract
For Mycobacterium tuberculosis, phenotypic methods for drug susceptibility testing of second-line drugs are poorly standardized and technically challenging. The Sensititre MYCOTB MIC plate (MYCOTB) is a microtiter plate containing lyophilized antibiotics and configured for determination of MICs to first- and second-line antituberculosis drugs. To evaluate the performance of MYCOTB for M. tuberculosis drug susceptibility testing using the Middlebrook 7H10 agar proportion method (APM) as the comparator, we conducted a two-site study using archived M. tuberculosis isolates from Uganda and the Republic of Korea. Thawed isolates were subcultured, and dilutions were inoculated into MYCOTB wells and onto 7H10 agar. MYCOTB results were read at days 7, 10, 14, and 21; APM results were read at 21 days. A total of 222 isolates provided results on both platforms. By APM, 106/222 (47.7%) of isolates were resistant to at least isoniazid and rifampin. Agreement between MYCOTB and APM with respect to susceptibility or resistance was ?92% for 7 of 12 drugs when a strict definition was used and ?96% for 10 of 12 drugs when agreement was defined by allowing a ± one-well range of dilutions around the APM critical concentration. For ethambutol, agreement was 80% to 81%. For moxifloxacin, agreement was 83% to 85%; incorporating existing DNA sequencing information for discrepant analysis raised agreement to 91% to 96%. For MYCOTB, the median time to plate interpretation was 10 days and interreader agreement was ?95% for all drugs. MYCOTB provided reliable results for M. tuberculosis susceptibility testing of first- and second-line drugs except ethambutol, and results were available sooner than those determined by APM.
Related JoVE Video
Optimal Triage Test Characteristics to Improve the Cost-Effectiveness of the Xpert MTB/RIF Assay for TB Diagnosis: A Decision Analysis.
PLoS ONE
PUBLISHED: 01-01-2013
Show Abstract
Hide Abstract
High costs are a limitation to scaling up the Xpert MTB/RIF assay (Xpert) for the diagnosis of tuberculosis in resource-constrained settings. A triaging strategy in which a sensitive but not necessarily highly specific rapid test is used to select patients for Xpert may result in a more affordable diagnostic algorithm. To inform the selection and development of particular diagnostics as a triage test we explored combinations of sensitivity, specificity and cost at which a hypothetical triage test will improve affordability of the Xpert assay.
Related JoVE Video
Elucidating emergence and transmission of multidrug-resistant tuberculosis in treatment experienced patients by whole genome sequencing.
PLoS ONE
PUBLISHED: 01-01-2013
Show Abstract
Hide Abstract
Understanding the emergence and spread of multidrug-resistant tuberculosis (MDR-TB) is crucial for its control. MDR-TB in previously treated patients is generally attributed to the selection of drug resistant mutants during inadequate therapy rather than transmission of a resistant strain. Traditional genotyping methods are not sufficient to distinguish strains in populations with a high burden of tuberculosis and it has previously been difficult to assess the degree of transmission in these settings. We have used whole genome analysis to investigate M. tuberculosis strains isolated from treatment experienced patients with MDR-TB in Uganda over a period of four years.
Related JoVE Video
Effectiveness of the standard WHO recommended retreatment regimen (category II) for tuberculosis in Kampala, Uganda: a prospective cohort study.
PLoS Med.
PUBLISHED: 02-07-2011
Show Abstract
Hide Abstract
Each year, 10%-20% of patients with tuberculosis (TB) in low- and middle-income countries present with previously treated TB and are empirically started on a World Health Organization (WHO)-recommended standardized retreatment regimen. The effectiveness of this retreatment regimen has not been systematically evaluated.
Related JoVE Video
Immunoregulation in TB: observations and implications.
Clin Transl Sci
PUBLISHED: 05-07-2010
Show Abstract
Hide Abstract
Regulation of the immune response during active tuberculosis (TB) has been partly deciphered. In pulmonary TB there is transient systemic immunosuppression due to overexpression of transforming growth factor beta and interleukin-10. This is superimposed on a primary T-cell defect. Locally there is intense inflammation (lung, pleural fluid) with overexpression of immunosuppressive factors (bronchoalveolar lavage) and extensive apoptosis. These observations suggest that immune therapies should be aimed at neutralizing the negative regulatory factors rather than accentuating an already intense immune response. Also a partially effective vaccine carries the potential risk of exacerbating disease.
Related JoVE Video
Differential expression of Toll-like receptors on human alveolar macrophages and autologous peripheral monocytes.
Respir. Res.
PUBLISHED: 01-05-2010
Show Abstract
Hide Abstract
Toll-like receptors (TLRs) are critical components in the regulation of pulmonary immune responses and the recognition of respiratory pathogens such as Mycobacterium Tuberculosis (M.tb). Through examination of human alveolar macrophages this study attempts to better define the expression profiles of TLR2, TLR4 and TLR9 in the human lung compartment which are as yet still poorly defined.
Related JoVE Video
Compartmentalized bronchoalveolar IFN-gamma and IL-12 response in human pulmonary tuberculosis.
Tuberculosis (Edinb)
PUBLISHED: 09-26-2009
Show Abstract
Hide Abstract
Human tuberculosis (TB) principally involves the lungs, where local immunity impacts on the load of Mycobacterium tuberculosis (M.tb). Because concomitants of local Th1 immunity are still under-explored in humans, we characterized immune responses in bronchoalveolar cells (BACs) and systemically in peripheral blood mononuclear cells (PBMCs) in persons with active pulmonary TB and in healthy community controls. PPD- and live M.tb-induced IFN-gamma-production were observed in CD4(+), CD8(+), gammadeltaTCR(+), and CD56(+) alveolar T cell subpopulations and NK cells (CD3(-)CD56(+)). IFN-gamma-producing CD4(+) T cells (mostly CD45RO(+)) were more abundant (p<0.05). M.tb-induced IL-12p70, but interestingly also IL-4, was increased (p<0.05) in BACs from TB patients. Constitutive expression of IL-12Rbeta1 and IL-12Rbeta2 mRNA in BACs and PBMCs and IFN-gammaR1 in BACs was similar in both study groups. Data were normalized to account for differences in proportions of alveolar T cells and macrophages in the study groups. IFN-gamma-production and its induction by IL-12R engagement occur virtually unimpaired in the bronchoalveolar spaces of patients with pulmonary TB. The reasons for the apparent failure to control M. tuberculosis growth during active pulmonary TB disease is unknown but could be the expression of locally acting immunosuppressive mechanisms that subvert the antimycobacterial effects of IFN-gamma.
Related JoVE Video
Comparison of rapid tests for detection of rifampicin-resistant Mycobacterium tuberculosis in Kampala, Uganda.
BMC Infect. Dis.
PUBLISHED: 02-06-2009
Show Abstract
Hide Abstract
Drug resistant tuberculosis (TB) is a growing concern worldwide. Rapid detection of resistance expedites appropriate intervention to control the disease. Several technologies have recently been reported to detect rifampicin resistant Mycobacterium tuberculosis directly in sputum samples. These include phenotypic culture based methods, tests for gene mutations and tests based on bacteriophage replication. The aim of the present study was to assess the feasibility of implementing technology for rapid detection of rifampicin resistance in a high disease burden setting in Africa.
Related JoVE Video
The emergence of extensively drug-resistant tuberculosis: a global health crisis requiring new interventions: Part II: scientific advances that may provide solutions.
Clin Transl Sci
PUBLISHED: 02-01-2009
Show Abstract
Hide Abstract
The need for new tuberculosis (TB) diagnostics has never been greater as TB in the HIV-infected is often sputum smear negative or extrapulmonary and may progress rapidly unless diagnosed and treated appropriately. In addition, the empirical treatment of patients with drug-resistant TB leads to the acquisition of additional resistance. Fortunately there is a robust and adequately funded developments pipeline including investigational rapid diagnostics that may replace smear, culture, and drug susceptibility testing. The dogma that drug resistance usually develops as a consequence of patient nonadherence has never been entirely plausible. Recent observations indicate that certain mutations in drug resistance genes promote the acquisition of additional resistance. Further, Mycobacterium tuberculosis (MTB) may demonstrate tolerant phenotypes due to induction of a multidrug-resistant like pump. It will be difficult to "treat our way" out of the problem of extensively drug-resistant (XDR)-TB without access to new interventions. Vaccines in development offer a distant hope. Promising new therapeutics in clinical trials may shorten the duration of treatment of TB, which will lessen the development of drug resistance or provide potent new and MTB specific agents that should be effective in treatment of XDR-TB.
Related JoVE Video
Variability of infectious aerosols produced during coughing by patients with pulmonary tuberculosis.
Am. J. Respir. Crit. Care Med.
Show Abstract
Hide Abstract
Mycobacterium tuberculosis is transmitted by infectious aerosols, but assessing infectiousness currently relies on sputum microscopy that does not accurately predict the variability in transmission.
Related JoVE Video
Clinical research and development of tuberculosis diagnostics: moving from silos to synergy.
J. Infect. Dis.
Show Abstract
Hide Abstract
The development, evaluation, and implementation of new and improved diagnostics have been identified as critical needs by human immunodeficiency virus (HIV) and tuberculosis researchers and clinicians alike. These needs exist in international and domestic settings and in adult and pediatric populations. Experts in tuberculosis and HIV care, researchers, healthcare providers, public health experts, and industry representatives, as well as representatives of pertinent US federal agencies (Centers for Disease Control and Prevention, Food and Drug Administration, National Institutes of Health, United States Agency for International Development) assembled at a workshop proposed by the Diagnostics Working Group of the Federal Tuberculosis Taskforce to review the state of tuberculosis diagnostics development in adult and pediatric populations.
Related JoVE Video
Ten challenges for TB biomarkers.
Tuberculosis (Edinb)
Show Abstract
Hide Abstract
The availability of tuberculosis (TB) biomarkers of protection (or: "surrogate endpoints of protection against active TB" (Biomarkers Definitions Working Group, 2001)) would greatly facilitate and accelerate TB vaccine development and increase the likelihood of success. TB biomarkers of protection could determine which vaccines in clinical trials are the most efficacious; which vaccine candidates and strategies are the most promising in early stages in the preclinical development pipeline (including relevant antigens, antigen delivery, live vaccines); and which combination vaccines (prime/boost) would be the most effective. Here we discuss ten major challenges for biomarker identification and validation in TB. Current major roadblocks and critical limitations in understanding TB pathogenesis are highlighted, and new solutions and strategies proposed.
Related JoVE Video
Coinfection-helminthes and tuberculosis.
Curr Opin HIV AIDS
Show Abstract
Hide Abstract
Tuberculosis (TB) continues to be a significant problem and a major cause of morbidity and mortality in the developing world despite decades of intensive efforts to combat the disease. The poverty in these endemic areas is associated with an increased incidence of tropical helminthic infections. The purpose of this review is to bring to the fore, the urgent need to unravel the potential consequences of helminth coinfection to tuberculosis disease pathogenesis and transmission.
Related JoVE Video

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.

How does it work?

We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

Video X seems to be unrelated to Abstract Y...

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.