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121.
122.
Petros Isaakidis Roma Paryani Samsuddin Khan Homa Mansoor Mamta Manglani Asmaa Valiyakath Peter Saranchuk Jennifer Furin 《PloS one》2013,8(7)
Background
Little is known about the treatment of multidrug-resistant tuberculosis (MDR-TB) in HIV-co-infected adolescents. This study aimed to present the intermediate outcomes of HIV-infected adolescents aged 10–19 years receiving second-line anti-TB treatment in a Médecins Sans Frontières (MSF) project in Mumbai, India.Methods
A retrospective review of medical records of 11 adolescents enrolled between July 2007 and January 2013 was undertaken. Patients were initiated on either empirical or individualized second-line ambulatory anti-TB treatment under direct observation.Results
The median age was 16 (IQR 14–18) years and 54% were female. Five (46%) adolescents had pulmonary TB (PTB), two (18%) extrapulmonary disease (EPTB) and four (36%) had both. Median CD4 count at the time of MDR-TB diagnosis was 162.7 cells/µl (IQR: 84.8–250.5). By January 2013, eight patients had final and 3 had interim outcomes. Favourable results were seen in four (36.5%) patients: one was cured and three were still on treatment with negative culture results. Seven patients (64%) had poor outcomes: four (36.5%) died and three (27%) defaulted. Three of the patients who died never started on antiretroviral and/or TB treatment and one died 16 days after treatment initiation. Two of the defaulted died soon after default. All patients (100%) on-treatment experienced adverse events (AEs): two required permanent discontinuation of the culprit drug and two were hospitalized due to AEs. No patient required permanent discontinuation of the entire second-line TB or antiretroviral regimens.Conclusions
Early mortality and mortality after default were the most common reasons for poor outcomes in this study. Early mortality suggests the need for rapid diagnosis and prompt treatment initiation, and adolescents might benefit from active contact-tracing and immediate referral. Default occurred at different times, suggesting the need for continuous, intensified and individualized psychosocial support for co-infected adolescents. Operational research among co-infected adolescents will be especially important in designing effective interventions for this vulnerable group. 相似文献123.
P Isaakidis B Varghese H Mansoor HS Cox J Ladomirska P Saranchuk E Da Silva S Khan R Paryani Z Udwadia GB Migliori G Sotgiu T Reid 《PloS one》2012,7(7):e40781
Background
Significant adverse events (AE) have been reported in patients receiving medications for multidrug- and extensively-drug-resistant tuberculosis (MDR-TB & XDR-TB). However, there is little prospective data on AE in MDR- or XDR-TB/HIV co-infected patients on antituberculosis and antiretroviral therapy (ART) in programmatic settings.Methods
Médecins Sans Frontières (MSF) is supporting a community-based treatment program for drug-resistant tuberculosis in HIV-infected patients in a slum setting in Mumbai, India since 2007. Patients are being treated for both diseases and the management of AE is done on an outpatient basis whenever possible. Prospective data were analysed to determine the occurrence and nature of AE.Results
Between May 2007 and September 2011, 67 HIV/MDR-TB co-infected patients were being treated with anti-TB treatment and ART; 43.3% were female, median age was 35.5 years (Interquartile Range: 30.5–42) and the median duration of anti-TB treatment was 10 months (range 0.5–30). Overall, AE were common in this cohort: 71%, 63% and 40% of patients experienced one or more mild, moderate or severe AE, respectively. However, they were rarely life-threatening or debilitating. AE occurring most frequently included gastrointestinal symptoms (45% of patients), peripheral neuropathy (38%), hypothyroidism (32%), psychiatric symptoms (29%) and hypokalaemia (23%). Eleven patients were hospitalized for AE and one or more suspect drugs had to be permanently discontinued in 27 (40%). No AE led to indefinite suspension of an entire MDR-TB or ART regimen.Conclusions
AE occurred frequently in this Mumbai HIV/MDR-TB cohort but not more frequently than in non-HIV patients on similar anti-TB treatment. Most AE can be successfully managed on an outpatient basis through a community-based treatment program, even in a resource-limited setting. Concerns about severe AE in the management of co-infected patients are justified, however, they should not cause delays in the urgently needed rapid scale-up of antiretroviral therapy and second-line anti-TB treatment. 相似文献124.
Petros D Grivas Kathleen C Day Andreas Karatsinides Alyssa Paul Nazia Shakir Iya Owainati Monica Liebert Lakshmi P Kunju Dafydd Thomas Maha Hussain Mark L Day 《Molecular medicine (Cambridge, Mass.)》2013,19(1):367-376
Members of the human epidermal growth factor receptor (HER) family play a significant role in bladder cancer progression and may underlie the development of chemotherapy resistance. Dacomitinib is an irreversible tyrosine kinase inhibitor with structural specificity for the catalytic domains of epidermal growth factor receptor (EGFR), HER2 and HER4 that has exhibited vigorous efficacy against other solid tumors. We evaluated the antitumor activity of dacomitinib in human bladder cancer cell lines expressing varying levels of HER family receptors. These cell lines also were established as bladder cancer xenografts in nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice to assess dacomitinib activity in vivo. Significant cytotoxic and cytostatic effects were noted in cells expressing elevated levels of the dacomitinib target receptors with apoptosis and cell cycle arrest being the predominant mechanisms of antitumor activity. Cells expressing lower levels of HER receptors were much less sensitive to dacomitinib. Interestingly, dacomitinib was more active than either trastuzumab or cetuximab in vitro, and exhibited increased growth inhibition of bladder tumor xenografts compared with lapatinib. Pharmacodynamic effects of dacomitinib included decreased E-cadherin (E-cad) expression, reduction of EGFR and extracellular signal-regulated kinase (ERK) phosphorylation and reduced mitotic count. Dacomitinib also inhibited tumor growth in a chemotherapy-resistant xenograft and, when combined with chemotherapy in a sensitive xenograft, exhibited superior antitumor effects compared with individual treatments. Evaluation in xenograft-bearing mice revealed that this combination was broadly feasible and well tolerated. In conclusion, dacomitinib exhibited pronounced activity both as a single agent and when combined with chemotherapy in human bladder cancer models. Further investigation of dacomitinib in the preclinical and clinical trial settings is being pursued. 相似文献
125.
The SfiI restriction endonuclease is a tetramer in which two subunits form a dimeric unit that contains one DNA binding cleft and the other two subunits contain a second cleft on the opposite side of the protein. Full activity requires both clefts to be filled with its recognition sequence: SfiI has low activity when bound to one site. The ability of SfiI to cleave non-cognate sites, one base pair different from the true site, was initially tested on substrates that lacked specific sites but which contained either one or multiple non-cognate sites. No cleavage of the DNA with one non-cognate site was detected, while a small fraction of the DNA with multiple sites was nicked. The alternative sequences were, however, cleaved in both strands, albeit at low levels, when the DNA also carried either a recognition site for SfiI or the termini generated by SfiI. Further tests employed a mutant of SfiI, altered at the dimer interface, which was known to be more active than wild-type SfiI when bound to a single site. This mutant similarly failed to cleave DNA with one non-cognate site, but cleaved the substrates with multiple non-cognate sites more readily than did the native enzyme. To cleave additional sites, SfiI thus needs to interact concurrently with either two non-cognate sites or one non-cognate and one cognate site (or the termini thereof), yet this arrangement is still restrained from cleaving the alternative site unless the communication pathway between the two DNA-binding clefts is disrupted. 相似文献
126.
Andrew Ramsay Luis E. Cuevas Catherine J. F. Mundy Carl-Michael Nathanson Petros Chirambo Russell Dacombe S. Bertel Squire Felix M. L. Salaniponi Sera Munthali 《PloS one》2009,4(11)
Background
To quantify the likely impact of recent WHO policy recommendations regarding smear microscopy and the introduction of appropriate low-cost fluorescence microscopy on a) case detection and b) laboratory workload.Methodology/Principal Findings
An audit of the laboratory register in an urban hospital, Lilongwe, Malawi, and the application of a simple modelling framework. The adoption of the new definition of a smear-positive case could directly increase case detection by up to 28%. Examining Ziehl-Neelsen (ZN) sputum smears for up to 10 minutes before declaring them negative has previously been shown to increase case detection (over and above that gained by the adoption of the new case definition) by 70% compared with examination times in routine practice. Three times the number of staff would be required to adequately examine the current workload of smears using ZN microscopy. Through implementing new policy recommendations and LED-based fluorescence microscopy the current laboratory staff complement could investigate the same number of patients, examining auramine-stained smears to an extent that is equivalent to a 10 minutes ZN smear examination.Conclusions/Significance
Combined implementation of the new WHO recommendations on smear microscopy and LED-based fluorescence microscopy could result in substantial increases in smear positive case-detection using existing human resources and minimal additional equipment. 相似文献127.
Paul J. Converse Kathleen D. Eisenach Sue A. Theus Eric L. Nuermberger Sandeep Tyagi Lan H. Ly Deborah E. Geiman Haidan Guo Scott T. Nolan Nicole C. Akar Lee G. Klinkenberg Radhika Gupta Shichun Lun Petros C. Karakousis Gyanu Lamichhane David N. McMurray Jacques H. Grosset William R. Bishai 《PloS one》2010,5(4)
Background
It has been hypothesized that the virulence of lab-passaged Mycobacterium tuberculosis and recombinant M. tuberculosis mutants might be reduced due to multiple in vitro passages, and that virulence might be augmented by passage of these strains through mice before quantitative virulence testing in the mouse or guinea pig aerosol models.Methodology/Principal Findings
By testing three M. tuberculosis H37Rv samples, one deletion mutant, and one recent clinical isolate for survival by the quantitative organ CFU counting method in mouse or guinea pig aerosol or intravenous infection models, we could discern no increase in bacterial fitness as a result of passaging of M. tuberculosis strains in mice prior to quantitative virulence testing in two animal models. Surface lipid expression as assessed by neutral red staining and thin-layer chromatography for PDIM analysis also failed to identify virulence correlates.Conclusions/Significance
These results indicate that animal passaging of M. tuberculosis strains prior to quantitative virulence testing in mouse or guinea pig models does not enhance or restore potency to strains that may have lost virulence due to in vitro passaging. It is critical to verify virulence of parental strains before genetic manipulations are undertaken and comparisons are made. 相似文献128.
129.
Background
HIV infection has been modifying both the epidemiology and outcome of parasite infections. Hence, this study was undertaken to determine the prevalence of Cryptosporidium and other intestinal parasite infections among HIV positives with and without Antiretroviral Treatment(ART) and its association with CD4+ T-cell count.Methods
A cross-sectional study was conducted at Fitche hospital focusing on HIV positives who came to hospital for follow-ups. A total of 378 HIV positive persons with and without ART participated in the study. Data on socio-demographic factors and diarrhoea status were obtained by interviewing all 214 with ART and 164 without ART. Stool samples were collected from all patients and examined for intestinal parasites using direct, formol-ether and modified acid-fast staining techniques.Results
The prevalence of intestinal parasite infections in this study was significantly higher among HIV positive persons not on ART. Specifically, the rate of infection with Cryptosporidium species, Blastocystis spp., Giardia lamblia, and Entamoeba histolytica/E. dispar were higher, particularly in those with CD4+ T-cell counts less than 200 cells/µL. Fifty seven percent of the study participants were on ART. Out of these 164/378 (43%) of the non-ART study participants were infected with at least one intestinal parasite species. Significant association was observed between lower CD4+ T-cell count (<200 cells/µL) and the prevalence of Cryptosporidium spp. and Blastocystis spp. The two parasites were significantly more prevalent in HIV positive non-ART patients.Conclusion
HIV infection increased the risk of having Cryptosporidium and other intestinal parasites and diarrhoea. Therefore, raising HIV positive’s immune status and screening for intestinal parasites is important. This study showed that patients who are taking ART had a lower prevalence of diarrhoea causing parasites and Cryptosporidium suggesting that ART through improvement of immune status of the patients may have contributed to controlling diarrhoea-causing parasites in HIV positive patients. 相似文献130.
Bineyam Taye Bereket Alemayehu Asaye Birhanu Kassu Desta Sisay Addisu Beyene Petros Gail Davey Aster Tsegaye 《PLoS neglected tropical diseases》2013,7(3)