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FABP5 Inhibition against PTEN-Mutant Therapy Resistant Prostate Cancer. Cancers (Basel) 2023; 16:60. [PMID: 38201488 PMCID: PMC10871093 DOI: 10.3390/cancers16010060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Revised: 11/20/2023] [Accepted: 12/13/2023] [Indexed: 01/12/2024] Open
Abstract
Resistance to standard of care taxane and androgen deprivation therapy (ADT) causes the vast majority of prostate cancer (PC) deaths worldwide. We have developed RapidCaP, an autochthonous genetically engineered mouse model of PC. It is driven by the loss of PTEN and p53, the most common driver events in PC patients with life-threatening diseases. As in human ADT, surgical castration of RapidCaP animals invariably results in disease relapse and death from the metastatic disease burden. Fatty Acid Binding Proteins (FABPs) are a large family of signaling lipid carriers. They have been suggested as drivers of multiple cancer types. Here we combine analysis of primary cancer cells from RapidCaP (RCaP cells) with large-scale patient datasets to show that among the 10 FABP paralogs, FABP5 is the PC-relevant target. Next, we show that RCaP cells are uniquely insensitive to both ADT and taxane treatment compared to a panel of human PC cell lines. Yet, they share an exquisite sensitivity to the small-molecule FABP5 inhibitor SBFI-103. We show that SBFI-103 is well tolerated and can strongly eliminate RCaP tumor cells in vivo. This provides a pre-clinical platform to fight incurable PC and suggests an important role for FABP5 in PTEN-deficient PC.
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Identifying non-tuberculosis mycobacteria: Is it time to introduce new molecular assays? S Afr Med J 2023; 113:4-5. [PMID: 37278260 DOI: 10.7196/samj.2022.v113i6.16771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Indexed: 06/07/2023] Open
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Characterisation of patients referred to a tertiary-level inherited cardiac condition clinic with suspected arrhythmogenic right ventricular cardiomyopathy (ARVC). BMC Cardiovasc Disord 2023; 23:14. [PMID: 36635648 PMCID: PMC9837886 DOI: 10.1186/s12872-022-03021-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 12/19/2022] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Arrhythmogenic right ventricular cardiomyopathy (ARVC) or arrhythmogenic cardiomyopathy is a rare inherited disease with incomplete penetrance and an environmental component. Although a rare disease, ARVC is a common cause of sudden cardiac death in young adults. Data on the different stages of ARVC remains scarce. The purpose of this study is to describe the initial presentation and cardiac phenotype of definite and non-definite ARVC for patients seen at a tertiary service. METHODS This is a single centre, observational cohort study of patients with definite and non-definite ARVC seen at the Inherited Cardiac Conditions services at University Hospital Birmingham (UHB) in the period 2010-2021. Patients were identified by interrogation of digital health records, medical history, imaging and by examining 12-lead electrocardiograms (ECG). RESULT The records of 1451 patients were reviewed; of those, 165 patients were at risk of ARVC (mean age 41 ± 17 years, 56% male). 60 patients fulfilled task force criteria for definite ARVC diagnosis (n = 40, 67% males), and 38 (72%) of them carried a known pathogenic variant. The remaining 105 patients (50% males) were non-definite, and of these 45 (62%) carried a known pathogenic variant. Patients in the definite group were more symptomatic, with palpitations (57% vs. 17%), syncope (35% vs. 6%) and shortness of breath (28% vs. 5%, p < 0.001). T-wave inversion in V1-V3 and epsilon waves were observed only in the definite group. Both PR interval and QRS duration were longer in the definite (170 ± 34 ms and 100 ± 19 ms, p < 0.001) compared to (149 ± 25 and 91 ± 14 ms, p = 0.005). Patients with definite ARVC had significantly larger RV end diastolic areas and significantly reduced biventricular function (RVEDA = 27 ± 10 cm2, RVFAC = 37 ± 11% and EF = 56 ± 12%) compared to the non-definite group (RVEDA = 18 ± 4 cm2, RVFAC 49 ± 6% and LVEF 64 ± 7%, p < 0.001). Sustained ventricular tachycardia (VT) occurred more frequently in the definite group compared to the non-definite group (27% vs. 2%, p < 0.001). Ventricular fibrillation was observed in the definite group only (8 of 60 patients, 13%). CONCLUSION Our study showed differences between definite and non-definite ARVC patients in terms of clinical, electrophysiological and imaging features. Major adverse cardiac events occurred more commonly in the definite group, but also were observed in non-definite ARVC. This single centre observational cohort study forms a basis for further prospective multicentre interventional studies.
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A very sneaky bug: perspectives of front-line clinicians on whole-genome sequencing for drug-resistant TB. Int J Tuberc Lung Dis 2022; 26:1180-1182. [PMID: 36447309 PMCID: PMC9728944 DOI: 10.5588/ijtld.22.0335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
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A test of infection should not be a "standard" for guiding TB preventive therapy in at-risk populations. Int J Tuberc Lung Dis 2022; 26:1092-1093. [PMID: 36281036 DOI: 10.5588/ijtld.22.0445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Pediatric delamanid treatment for children with rifampicin-resistant TB. Int J Tuberc Lung Dis 2022; 26:986-988. [PMID: 36163672 PMCID: PMC9524514 DOI: 10.5588/ijtld.22.0264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Early mortality during rifampicin-resistant TB treatment. Int J Tuberc Lung Dis 2022; 26:150-157. [PMID: 35086627 PMCID: PMC8802559 DOI: 10.5588/ijtld.21.0494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Accepted: 09/30/2021] [Indexed: 12/05/2022] Open
Abstract
BACKGROUND: Data suggest that treatment with newer TB drugs (linezolid [LZD], bedaquiline [BDQ] and delamanid [DLM]), used in Khayelitsha, South Africa, since 2012, reduces mortality due to rifampicin-resistant TB (RR-TB).METHODS: This was a retrospective cohort study to assess 6-month mortality among RR-TB patients diagnosed between 2008 and 2019.RESULTS: By 6 months, 236/2,008 (12%) patients died; 12% (78/651) among those diagnosed in 2008-2011, and respectively 8% (49/619) and 15% (109/738) with and without LZD/BDQ/DLM in 2012-2019. Multivariable analysis showed a small, non-significant mortality reduction with LZD/BDQ/DLM use compared to the 2008-2011 period (aOR 0.79, 95% CI 0.5-1.2). Inpatient treatment initiation (aOR 3.2, 95% CI 2.4-4.4), fluoroquinolone (FQ) resistance (aOR 2.7, 95% CI 1.8-4.2) and female sex (aOR 1.5, 95% CI 1.1-2.0) were also associated with mortality. When restricted to 2012-2019, use of LZD/BDQ/DLM was associated with lower mortality (aOR 0.58, 95% CI 0.39-0.87).CONCLUSIONS: While LZD/BDQ/DLM reduced 6-month mortality between 2012 and 2019, there was no significant effect overall. These findings may be due to initially restricted LZD/BDQ/DLM use for those with high-level resistance or treatment failure. Additional contributors include increased treatment initiation among individuals who would have otherwise died before treatment due to universal drug susceptibility testing from 2012, an effect that also likely contributed to higher mortality among females (survival through to care-seeking).
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Diverse clinical and social circumstances: developing patient-centred care for DR-TB patients in South Africa. Public Health Action 2021; 11:120-125. [PMID: 34567987 PMCID: PMC8455019 DOI: 10.5588/pha.20.0083] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 04/12/2021] [Indexed: 11/10/2022] Open
Abstract
OBJECTIVE To describe the medical, socio-economic and geographical profiles of patients with rifampicin-resistant TB (RR-TB) and the implications for the provision of patient-centred care. SETTING Thirteen districts across three South African provinces. DESIGN This descriptive study examined laboratory and healthcare facility records of 194 patients diagnosed with RR-TB in the third quarter of 2016. RESULTS The median age was 35 years; 120/194 (62%) of patients were male. Previous TB treatment was documented in 122/194 (63%) patients and 56/194 (29%) had a record of fluoroquinolone and/or second-line injectable resistance. Of 134 (69%) HIV-positive patients, viral loads were available for 68/134 (51%) (36/68 [53%] had viral loads of >1000 copies/ml) and CD4 counts were available for 92/134 (69%) (20/92 [22%] had CD4 <50 cells/mm3). Patients presented with varying other comorbidities, including hypertension (13/194, 7%) and mental health conditions (11/194, 6%). Of 194 patients, 44 (23%) were reported to be employed. Other socio-economic challenges included substance abuse (17/194, 9%) and ill family members (17/194, 9%). Respectively 13% and 42% of patients were estimated to travel more than 20 km to reach their diagnosing and treatment-initiating healthcare facility. CONCLUSIONS RR-TB patients had diverse medical and social challenges highlighting the need for integrated, differentiated and patient-centred healthcare to better address specific needs and underlying vulnerabilities of individual patients.
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Drug-resistant tuberculosis patient care journeys in South Africa: a pilot study using routine laboratory data. Int J Tuberc Lung Dis 2021; 24:83-91. [PMID: 32005310 DOI: 10.5588/ijtld.19.0100] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
SETTING: Thirteen districts in Eastern Cape (EC), KwaZulu-Natal (KZN) and Western Cape (WC) Provinces, South Africa.OBJECTIVE: To pilot a methodology for describing and visualising healthcare journeys among drug-resistant tuberculosis (DR-TB) patients using routine laboratory records.DESIGN: Laboratory records were obtained for 195 patients with laboratory-detected rifampicin-resistant TB (RR-TB) during July-September 2016. Health facility visits identified from these data were plotted to visualise patient healthcare journeys. Data were verified by facility visits.RESULTS: In the 9 months after the index RR-TB sample was collected, patients visited a mean of 2.3 health facilities (95% CI 2.1-2.6), with 9% visiting ≥4 facilities. The median distance travelled by patients from rural areas (116 km, interquartile range [IQR] 50-290) was greater than for urban patients (51 km, IQR 9-140). A median of 21% of patient's time was spent under the care of primary healthcare facilities: this was respectively 6%, 37% and 39% in KZN, EC and WC. Journey patterns were generally similar within districts. Some reflected a semi-centralised model of care where patients were referred to regional hospitals; other journeys showed greater involvement of primary care.CONCLUSION: Routine laboratory data can be used to explore DR-TB patient healthcare journeys and show how the use of healthcare services for DR-TB varies in different settings.
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Continued use of stigmatising language in the scientific literature for TB. Int J Tuberc Lung Dis 2020; 24:1299-1301. [PMID: 33317675 DOI: 10.5588/ijtld.20.0493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Discovering a new drug is only the beginning: progress and challenges in expanding access to BDQ for MDR-TB treatment. Int J Tuberc Lung Dis 2020; 24:985-986. [DOI: 10.5588/ijtld.20.0562] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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SOAT1 promotes mevalonate pathway dependency in pancreatic cancer. J Exp Med 2020; 217:151922. [PMID: 32633781 PMCID: PMC7478739 DOI: 10.1084/jem.20192389] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 03/28/2020] [Accepted: 05/12/2020] [Indexed: 12/31/2022] Open
Abstract
Pancreatic ductal adenocarcinoma (PDAC) has a dismal prognosis, and new therapies are needed. Altered metabolism is a cancer vulnerability, and several metabolic pathways have been shown to promote PDAC. However, the changes in cholesterol metabolism and their role during PDAC progression remain largely unknown. Here we used organoid and mouse models to determine the drivers of altered cholesterol metabolism in PDAC and the consequences of its disruption on tumor progression. We identified sterol O-acyltransferase 1 (SOAT1) as a key player in sustaining the mevalonate pathway by converting cholesterol to inert cholesterol esters, thereby preventing the negative feedback elicited by unesterified cholesterol. Genetic targeting of Soat1 impairs cell proliferation in vitro and tumor progression in vivo and reveals a mevalonate pathway dependency in p53 mutant PDAC cells that have undergone p53 loss of heterozygosity (LOH). In contrast, pancreatic organoids lacking p53 mutation and p53 LOH are insensitive to SOAT1 loss, indicating a potential therapeutic window for inhibiting SOAT1 in PDAC.
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Novel insights into breast cancer copy number genetic heterogeneity revealed by single-cell genome sequencing. eLife 2020; 9:51480. [PMID: 32401198 PMCID: PMC7220379 DOI: 10.7554/elife.51480] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Accepted: 04/03/2020] [Indexed: 11/13/2022] Open
Abstract
Copy number alterations (CNAs) play an important role in molding the genomes of breast cancers and have been shown to be clinically useful for prognostic and therapeutic purposes. However, our knowledge of intra-tumoral genetic heterogeneity of this important class of somatic alterations is limited. Here, using single-cell sequencing, we comprehensively map out the facets of copy number alteration heterogeneity in a cohort of breast cancer tumors. Ou/var/www/html/elife/12-05-2020/backup/r analyses reveal: genetic heterogeneity of non-tumor cells (i.e. stroma) within the tumor mass; the extent to which copy number heterogeneity impacts breast cancer genomes and the importance of both the genomic location and dosage of sub-clonal events; the pervasive nature of genetic heterogeneity of chromosomal amplifications; and the association of copy number heterogeneity with clinical and biological parameters such as polyploidy and estrogen receptor negative status. Our data highlight the power of single-cell genomics in dissecting, in its many forms, intra-tumoral genetic heterogeneity of CNAs, the magnitude with which CNA heterogeneity affects the genomes of breast cancers, and the potential importance of CNA heterogeneity in phenomena such as therapeutic resistance and disease relapse. Cells in the body remain healthy by tightly preventing and repairing random changes, or mutations, in their genetic material. In cancer cells, however, these mechanisms can break down. When these cells grow and multiply, they can then go on to accumulate many mutations. As a result, cancer cells in the same tumor can each contain a unique combination of genetic changes. This genetic heterogeneity has the potential to affect how cancer responds to treatment, and is increasingly becoming appreciated clinically. For example, if a drug only works against cancer cells carrying a specific mutation, any cells lacking this genetic change will keep growing and cause a relapse. However, it is still difficult to quantify and understand genetic heterogeneity in cancer. Copy number alterations (or CNAs) are a class of mutation where large and small sections of genetic material are gained or lost. This can result in cells that have an abnormal number of copies of the genes in these sections. Here, Baslan et al. set out to explore how CNAs might vary between individual cancer cells within the same tumor. To do so, thousands of individual cancer cells were isolated from human breast tumors, and a technique called single-cell genome sequencing used to screen the genetic information of each of them. These experiments confirmed that CNAs did differ – sometimes dramatically – between patients and among cells taken from the same tumor. For example, many of the cells carried extra copies of well-known cancer genes important for treatment, but the exact number of copies varied between cells. This heterogeneity existed for individual genes as well as larger stretches of DNA: this was the case, for instance, for an entire section of chromosome 8, a region often affected in breast and other tumors. The work by Baslan et al. captures the sheer extent of genetic heterogeneity in cancer and in doing so, highlights the power of single-cell genome sequencing. In the future, a finer understanding of the genetic changes present at the level of an individual cancer cell may help clinicians to manage the disease more effectively.
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Adverse events among people on delamanid for rifampicin-resistant tuberculosis in a high HIV prevalence setting. Int J Tuberc Lung Dis 2020; 23:1017-1023. [PMID: 31615610 DOI: 10.5588/ijtld.18.0651] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
SETTING: Patients with rifampicin-resistant tuberculosis (RR-TB) in the township of Khayelitsha, South Africa, were offered delamanid (DLM) within a decentralised RR-TB treatment programme.OBJECTIVE: To describe adverse events (AEs) among HIV-positive and negative people receiving DLM for RR-TB in a programmatic setting.DESIGN: Patients were followed up monthly for blood, electrocardiography and clinical monitoring and AEs were assessed for severity grade, seriousness and relationship to DLM.RESULTS: Fifty-eight patients (55% male; median age 35 years, interquartile range [IQR] 28-42) started DLM; 46 (79%) were HIV-positive, median CD4 count 173 cells/mm³ (IQR 70-294). Fifty (86%) patients experienced ≥1 new or worsening AE after starting DLM, most commonly vomiting, QTcB >450 ms and/or myalgia. Serious and/or severe AEs were experienced by 22 (38%) patients; three HIV-positive patients died (not related to DLM). HIV status was not significantly associated with number (P = 0.089) or severity/seriousness (P = 0.11) of AEs during exposure to DLM. Two (3%) patients had DLM withdrawn due to AEs.CONCLUSION: AEs during RR-TB treatment, both before and during DLM exposure, were common, with relatively few serious/severe AEs considered related to DLM and no significant association with HIV status. Clinical and electrocardiography monitoring should be prioritised in the first two months after starting DLM.
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Health care gaps in the global burden of drug-resistant tuberculosis. Int J Tuberc Lung Dis 2020; 23:125-135. [PMID: 30808447 DOI: 10.5588/ijtld.18.0866] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The drug-resistant tuberculosis (DR-TB) cascade-from estimated or incident cases to numbers successfully treated or disease-free survival-has long been characterised by sharp declines at each step in the cascade. The losses along the cascade vary across different settings, and the reasons why some countries have a higher burden of DR-TB are complex and multifactorial; broadly, weak health systems, inadequate financing and poverty all impact differential access to DR-TB care. Within a human rights framework that mandates the right to health and the right to benefit from scientific progress, the aim of this review is to focus on describing inequities in access to DR-TB care at critical points in the cascade.
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Abstract
Drug-resistant tuberculosis (DR-TB) is challenging to diagnose, treat, and prevent, but this situation is slowly changing. If the world is to drastically reduce the incidence of DR-TB, we must stop creating new DR-TB as an essential first step. The DR-TB epidemic that is ongoing should also be directly addressed. First-line drug resistance must be rapidly detected using universal molecular testing for resistance to at least rifampin and, preferably, other key drugs at initial TB diagnosis. DR-TB treatment outcomes must also improve dramatically. Effective use of currently available, new, and repurposed drugs, combined with patient-centered treatment that aids adherence and reduces catastrophic costs, are essential. Innovations within sight, such as short, highly effective, broadly indicated regimens, paired with point-of-care drug susceptibility testing, could accelerate progress in treatment outcomes. Preventing or containing resistance to second-line and novel drugs is also critical and will require high-quality systems for diagnosis, regimen selection, and treatment monitoring. Finally, earlier detection and/or prevention of DR-TB is necessary, with particular attention to airborne infection control, case finding, and preventive therapy for contacts of patients with DR-TB. Implementing these strategies can overcome the barrier that DR-TB represents for global TB elimination efforts, and could ultimately make global elimination of DR-TB (fewer than one annual case per million population worldwide) attainable. There is a strong cost-effectiveness case to support pursuing DR-TB elimination; however, achieving this goal will require substantial global investment plus political and societal commitment at national and local levels.
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EMERGENCE OF BEDAQUILINE RESISTANCE AFTER COMPLETION OF BEDAQUILINE-BASED DRUGRESISTANT TB TREATMENT: A CASE STUDY FROM SOUTH AFRICA. ACTA ACUST UNITED AC 2019. [DOI: 10.15789/2220-7619-2018-4-6.11] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Time to treatment for rifampicin-resistant tuberculosis: systematic review and meta-analysis. Int J Tuberc Lung Dis 2018; 21:1173-1180. [PMID: 29037299 PMCID: PMC5644740 DOI: 10.5588/ijtld.17.0230] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND: To reduce transmission and improve patient outcomes, rapid diagnosis and treatment of rifampicin-resistant tuberculosis (RR-TB) is required. OBJECTIVE: To conduct a systematic review and meta-analysis assessing time to treatment for RR-TB and variability using diagnostic testing methods and treatment delivery approach. DESIGN: Studies from 2000 to 2015 reporting time to second-line treatment initiation were selected from PubMed and published conference abstracts. RESULTS: From 53 studies, 83 cohorts (13 034 patients) were included. Overall weighted mean time to treatment from specimen collection was 81 days (95%CI 70–91), and was shorter with ambulatory (57 days, 95%CI 40–74) than hospital-based treatment (86 days, 95%CI 71–102). Time to treatment was shorter with genotypic susceptibility testing (38 days, 95%CI 27–49) than phenotypic testing (108 days, 95%CI 98–117). The mean percentage of diagnosed patients initiating treatment was 76% (95%CI 70–83, range 25–100). CONCLUSION: Time to second-line anti-tuberculosis treatment initiation is extremely variable across studies, and often unnecessarily long. Reduced delays are associated with genotypic testing and ambulatory treatment settings. Routine monitoring of the proportion of diagnosed patients initiating treatment and time to treatment are necessary to identify areas for intervention.
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Missed opportunities for earlier diagnosis of rifampicin-resistant tuberculosis despite access to Xpert ® MTB/RIF. Int J Tuberc Lung Dis 2018; 21:1100-1105. [PMID: 28911352 DOI: 10.5588/ijtld.17.0372] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
OBJECTIVE To assess the proportion of rifampicin-resistant tuberculosis (RR-TB) patients with potential earlier RR-TB diagnoses in Khayelitsha, South Africa. DESIGN We conducted a retrospective analysis among RR-TB patients diagnosed from 2012 to 2014. Patients were considered to have missed opportunities for earlier diagnosis if 1) they were incorrectly screened according to the Western Cape diagnostic algorithm; 2) the first specimen was not tested using Xpert® MTB/RIF; 3) no specimen was ever tested; or 4) the initial Xpert test showed a negative result, but no subsequent specimen was sent for follow-up testing in human immunodeficiency virus-positive patients. RESULTS Among 543 patients, 386 (71%) were diagnosed with Xpert and 112 (21%) had had at least one presentation at a health care facility within the 6 months before the presentation at which RR-TB was diagnosed. Overall, 95/543 (18%) patients were screened incorrectly at some point: 48 at diagnostic presentation only, 38 at previous presentation only, and 9 at both previous and diagnostic presentations. CONCLUSIONS These data show that a significant proportion of RR-TB patients might have been diagnosed earlier, and suggest that case detection could be improved if diagnostic algorithms were followed more closely. Further training and monitoring is required to ensure the greatest benefit from universal Xpert implementation.
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Utility of Single-Cell Genomics in Diagnostic Evaluation of Prostate Cancer. Cancer Res 2017; 78:348-358. [PMID: 29180472 DOI: 10.1158/0008-5472.can-17-1138] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Revised: 08/23/2017] [Accepted: 11/10/2017] [Indexed: 12/18/2022]
Abstract
A distinction between indolent and aggressive disease is a major challenge in diagnostics of prostate cancer. As genetic heterogeneity and complexity may influence clinical outcome, we have initiated studies on single tumor cell genomics. In this study, we demonstrate that sparse DNA sequencing of single-cell nuclei from prostate core biopsies is a rich source of quantitative parameters for evaluating neoplastic growth and aggressiveness. These include the presence of clonal populations, the phylogenetic structure of those populations, the degree of the complexity of copy-number changes in those populations, and measures of the proportion of cells with clonal copy-number signatures. The parameters all showed good correlation to the measure of prostatic malignancy, the Gleason score, derived from individual prostate biopsy tissue cores. Remarkably, a more accurate histopathologic measure of malignancy, the surgical Gleason score, agrees better with these genomic parameters of diagnostic biopsy than it does with the diagnostic Gleason score and related measures of diagnostic histopathology. This is highly relevant because primary treatment decisions are dependent upon the biopsy and not the surgical specimen. Thus, single-cell analysis has the potential to augment traditional core histopathology, improving both the objectivity and accuracy of risk assessment and inform treatment decisions.Significance: Genomic analysis of multiple individual cells harvested from prostate biopsies provides an indepth view of cell populations comprising a prostate neoplasm, yielding novel genomic measures with the potential to improve the accuracy of diagnosis and prognosis in prostate cancer. Cancer Res; 78(2); 348-58. ©2017 AACR.
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The devil we know: is the use of injectable agents for the treatment of MDR-TB justified? Int J Tuberc Lung Dis 2017; 21:1114-1126. [DOI: 10.5588/ijtld.17.0468] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Whole-genome single-cell copy number profiling from formalin-fixed paraffin-embedded samples. Nat Med 2017; 23:376-385. [PMID: 28165479 PMCID: PMC5608257 DOI: 10.1038/nm.4279] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 01/09/2017] [Indexed: 12/16/2022]
Abstract
A substantial proportion of tumors consist of genotypically distinct subpopulations of cancer cells. This intratumor genetic heterogeneity poses a substantial challenge for the implementation of precision medicine. Single-cell genomics constitutes a powerful approach to resolve complex mixtures of cancer cells by tracing cell lineages and discovering cryptic genetic variations that would otherwise be obscured in tumor bulk analyses. Because of the chemical alterations that result from formalin fixation, single-cell genomic approaches have largely remained limited to fresh or rapidly frozen specimens. Here we describe the development and validation of a robust and accurate methodology to perform whole-genome copy-number profiling of single nuclei obtained from formalin-fixed paraffin-embedded clinical tumor samples. We applied the single-cell sequencing approach described here to study the progression from in situ to invasive breast cancer, which revealed that ductal carcinomas in situ show intratumor genetic heterogeneity at diagnosis and that these lesions may progress to invasive breast cancer through a variety of evolutionary processes.
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TGF-β reduces DNA ds-break repair mechanisms to heighten genetic diversity and adaptability of CD44+/CD24- cancer cells. eLife 2017; 6:e21615. [PMID: 28092266 PMCID: PMC5345931 DOI: 10.7554/elife.21615] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2016] [Accepted: 01/14/2017] [Indexed: 12/21/2022] Open
Abstract
Many lines of evidence have indicated that both genetic and non-genetic determinants can contribute to intra-tumor heterogeneity and influence cancer outcomes. Among the best described sub-population of cancer cells generated by non-genetic mechanisms are cells characterized by a CD44+/CD24- cell surface marker profile. Here, we report that human CD44+/CD24- cancer cells are genetically highly unstable because of intrinsic defects in their DNA-repair capabilities. In fact, in CD44+/CD24- cells, constitutive activation of the TGF-beta axis was both necessary and sufficient to reduce the expression of genes that are crucial in coordinating DNA damage repair mechanisms. Consequently, we observed that cancer cells that reside in a CD44+/CD24- state are characterized by increased accumulation of DNA copy number alterations, greater genetic diversity and improved adaptability to drug treatment. Together, these data suggest that the transition into a CD44+/CD24- cell state can promote intra-tumor genetic heterogeneity, spur tumor evolution and increase tumor fitness.
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Acute care - an important component of the continuum of care for HIV and tuberculosis in developing countries. Anaesthesia 2016; 72:147-150. [PMID: 27869303 DOI: 10.1111/anae.13604] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Abstract P1-16-03: Quantitative versus semi-quantitative assessments of radiation-induced pulmonary fibrosis post adjuvant breast radiotherapy. Cancer Res 2016. [DOI: 10.1158/1538-7445.sabcs15-p1-16-03] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Objective
To evaluate the quantitative versus semi-quantitative assessments of radiation induced pulmonary fibrosis (RIPF) post adjuvant breast radiotherapy (RT).
Methods
High resolution computed tomography (HRCT) assessed lung physical density changes (CTD) and physician identified HRCT visual grading scores (CTS) were analysed at the minimum of 12 months post RT at one institution. The treated side in-portal lung regions for CTD and CTS assessments were: central-axis (CA) + regions 5cm superior & inferior to CA and the corresponding mid anterolateral region respectively. Respiratory motion was accounted for by subtracting the untreated side lung density from the treated side. Mean lung densities correspond to each voxels were automatically calculated by Pinnacle software (Phillips, Eindhoven, The-Netherlands). Grading of CTS was according to the RTOG/EORTC (grade 0, 1, 2, and 3 defined as none, slight, patchy, and dense HRCT appearance respectively) and analysed by a radiologist (JL) and re-checked a radiation oncologist (PG).
Results
Total numbers of 403 patients were analysed. A substantial association was verified between CTD and CTS assessment. An increase of ∼0.01 g/ml (95% CI 0.003-0.02) in CTD with each CTS score increase of 1 was observed (Table-1a). The RIPF can be categorised quantitatively into three groups of CTS 0 vs. 1-2 vs. 3 based on the mean CTD (Table-1b).
Table-1a. Correlation between CTD and CTS method. Table-1b. Grouping of CTS based on CTD methodTable-1a. Correlation between CTD and CTS methodCTSTreated side mean CTD - LeftTreated side mean CTD - RightMean Total00.055 (119)-0.011 (136)0.020 (255)10.065 (60)0.005 (56)0.036 (116)20.083 (15)0.012 (13)0.050 (28)30.108 (4)00.108 (4)Total0.061 (198)-0.005 (205)0.028 (403)Table-1b. Grouping of CTS based on CTD methodCTSTreated side mean CTD - LeftTreated side mean CTD - RightMean Total95% Confidence interval00.055 (119)-0.011 (136)0.020 (255)0.012-0.0271-20.069 (75)0.006 (69)0.039 (144)0.029-0.04830.108 (4)00.108 (4)0.079-0.137
A cut off CTD of 0.089 g/ml exemplified the best compromise between sensitivity (100%) and specificity (88.2%) for dense HRCT appearance. However, there was no good compromise of CTD cut off for slight and patchy HRCT score possibly due to intra observer variation and the scale of the CTD measure (small increase in CTD may not be detected visually by the observer). Multivariable analysis revealed increasing age, current smoker, V20 ≥ 10% (the volume of lung that was covered by the 20Gy isodose line), central lung distance ≥ 2cm (the distance between posterior RT tangents and the chest wall), combined endocrine & chemotherapy, and treated side mean CTD to be significantly associated with development of grade ≥1 RIPF.
Conclusions
There was a good correlation between quantitative (CTD) and semi-quantitative (CTS) assessment of RIPF post adjuvant breast RT. The CTD method could be advantageous for both routine clinical practice and future clinical trials that require more detailed quantification of dense RIPF.
Citation Format: Pramana A, Browne L, Cox H, Saba A, Pham K, Trakis S, Crawford K, Hall M, Batchelor N, Lim J, Graham P. Quantitative versus semi-quantitative assessments of radiation-induced pulmonary fibrosis post adjuvant breast radiotherapy. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-16-03.
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Patients' costs associated with seeking and accessing treatment for drug-resistant tuberculosis in South Africa. Int J Tuberc Lung Dis 2015; 19:1513-9. [PMID: 26614194 PMCID: PMC6548556 DOI: 10.5588/ijtld.15.0341] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
SETTING South Africa is one of the world's 22 high tuberculosis (TB) burden countries, with the second highest number of notified rifampicin-resistant TB (R(R)-TB) and multidrug-resistant TB (MDR-TB) cases. OBJECTIVE To estimate patient costs associated with the diagnosis and treatment of R(R)-TB/MDR-TB in South Africa. DESIGN Patients diagnosed with R(R)-TB/MDR-TB and accessing care at government health care facilities were surveyed using a structured questionnaire. Direct and indirect costs associated with accessing R(R)-TB/MDR-TB care were estimated at different treatment durations for each patient. RESULTS A total of 134 patients were surveyed: 84 in the intensive phase and 50 in the continuation phase of treatment, 82 in-patients and 52 out-patients. The mean monthly patient costs associated with the diagnosis and treatment of R(R)-TB/MDR-TB were higher during the intensive phase than the continuation phase (US$235 vs. US$188) and among in-patients than among out-patients (US$269 vs. US$122). Patients in the continuation phase and those accessing care as out-patients reported higher out-of-pocket costs than other patients. Most patients did not access social protection for costs associated with R(R)-TB/MDR-TB illness. CONCLUSION Despite free health care, patients bear high costs when accessing diagnosis and treatment services for R(R)-TB/MDR-TB; appropriate social protection mechanisms should be provided to assist them in coping with these costs.
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Decentralised care for the management of child contacts of multidrug-resistant tuberculosis. Public Health Action 2015; 2:66-70. [PMID: 26392954 DOI: 10.5588/pha.12.0023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Accepted: 08/05/2012] [Indexed: 11/10/2022] Open
Abstract
SETTING Cape Town, South Africa. OBJECTIVE To determine the number of multidrug-resistant tuberculosis (MDR-TB) child contacts routinely identified by health services, and whether a model of decentralised care improves access. METHODS All MDR-TB source cases registered in Cape Town from April 2010 to March 2011 were included. All child contacts assessed at hospital and outreach clinics were recorded from May 2010 to June 2011. Electronic probabilistic matching was used to match source cases with potential child contacts; the number of children accessing decentralised (Khayelitsha) and hospital-based care was compared. RESULTS Of 1221 MDR-TB source cases identified, 189 (15.5%) were registered in Khayelitsha; 31 (16.4%) had at least one child contact assessed. In contrast, 95 (9.2%) of the 1032 source cases diagnosed in the other Cape Town subdistricts (hospital-based care) had at least one child contact assessed (P = 0.003). Children in Khayelitsha were seen at a median of 71 days (interquartile range [IQR] 37-121 days) after source case diagnosis compared to 90 days (IQR 56-132 days) in other subdistricts (P = 0.15). CONCLUSION Although decentralised care led to an increased number of child contacts being evaluated, both models led to the assessment of a small number of potential child MDR-TB contacts, with considerable delay in assessment.
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Abstract 4735: Single-cell sequencing from formalin-fixed paraffin-embedded breast cancers: a powerful tool to address intratumor genetic heterogeneity. Cancer Res 2015. [DOI: 10.1158/1538-7445.am2015-4735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: At diagnosis, tumors often consist of multiple, genotypically distinct cell populations. Genome sequencing of single cells has opened new avenues of investigation, yet the application of this technology remains limited to fresh/frozen tissue samples. Here, we describe and validate a method to perform single-cell massively parallel sequencing using DNA extracted from individual nuclei from FFPE tumor samples.
Methods: Tissue sections are deparaffinized and the area of interest microdissected, DNA is reverse-crosslinked and the extracellular matrix is digested. Extracted single nuclei are then FACS-sorted, lysed and the whole genome repaired using a broad-spectrum DNA-repair enzyme cocktail. Repaired DNA is whole genome amplified (WGA) using GenomePlex WGA4 (Sigma-Aldrich) with modifications for heavily damaged genomic templates. Illumina sequencing libraries are generated using standard approaches followed by multiplex sequencing on an Illumina HiSeq2000. To obtain copy number (CN) profiles, single-cell sequencing data are mapped to the reference genome with PCR duplicates removed. Uniquely mapped reads are allocated and counted in genomic intervals of variable length (bins) with CN states roughly proportional to the number of allocated sequencing reads. Bin counts are then normalized on the basis of GC-content, segmented and transformed to CN values to identify long contiguous regions of equivalent CN.
Results: As a proof-of-principle we performed single-cell CN profiling on two aneuploid synchronous ductal carcinomas in situ (DCIS)/invasive ductal carcinomas (IDCs), where both FFPE and frozen material was available. Using our novel methodology, 24 single nuclei were multiplexed/lesion. An average of 3 million reads/cell (average coverage of 0.1X/cell) was obtained, providing sufficient data to infer CN profiles of single cells accurately. These data were successfully employed to identify non-neoplastic cells and distinct clonal lineages of neoplastic cells within each lesion. The data obtained from the analysis of FFPE samples were concordant with those obtained from the analysis of matched frozen samples.
Conclusions: We developed a robust procedure to perform single-cell massively parallel sequencing of individual nuclei isolated from FFPE samples, providing the opportunity to unlock pathology archives for studies aiming to catalog and dissect the biological and clinical relevance of intra-tumor genetic heterogeneity.
Citation Format: Luciano G. Martelotto, Rita A. Sakr, Timour Baslan, Linda Rodgers, Hilary Cox, Jude Kendall, Tari A. King, Britta Weigelt, James Hicks, Jorge S. Reis-Filho. Single-cell sequencing from formalin-fixed paraffin-embedded breast cancers: a powerful tool to address intratumor genetic heterogeneity. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4735. doi:10.1158/1538-7445.AM2015-4735
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Abstract 2989: Intra-tumor heterogeneity and clonal changes in the progression of DCIS to invasiveness: Combined tumor bulk and single cell analysis. Cancer Res 2015. [DOI: 10.1158/1538-7445.am2015-2989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
INTRODUCTION: Ductal carcinoma in situ (DCIS) is a clonal intraductal proliferation of epithelial cells which acts as a non-obligate precursor of invasive breast cancer (IBC), yet the genetic events leading to the acquisition of invasive behavior remain unclear. We hypothesize that DCIS is composed of mosaics of genetically diverse tumor cell clones, and that the process of invasion is an evolutionary bottleneck. To test this hypothesis we performed a detailed characterization of the repertoire of genetic alterations and intra-tumor genetic heterogeneity in synchronously diagnosed DCIS and IBC using NextGen sequencing of bulk tumor and single cells.
METHODS: DNA extracted from fresh frozen, microdissected DCIS, IBC and adjacent normal tissue was subjected to whole exome sequencing on an Illumina HiSeq2000. Reads were aligned to the reference human genome hg19. Single nucleotide variants (SNVs) were called by MuTect, and gene copy number alterations were determined using VarScan2. Single nuclei were isolated from 100μm serial sections microdissected to separate DCIS and IBC. Individual nuclei were FACS-sorted into a 96-well plate, lysed and whole genome amplified. Amplified DNA samples were barcoded, pooled and sequenced on a HiSeq2000. Single cell sequencing data were mapped to the reference genome and uniquely mapped reads were allocated into bins, normalized, segmented and CN values generated.
RESULTS: In 6 cases of synchronous DCIS and IBC, a median of 41 and 47 non-synonymous mutations were found in each component, respectively. The somatic mutations identified in both DCIS and adjacent IBC components affected known driver breast cancer genes, including AKT1, PIK3CA, GATA3, MAP2K4 and TP53. Interestingly, we also found mutations restricted to either DCIS or IBC: ATRX (IBC-3); ALK and PKD2 (IBC-5); ESR1 (DCIS-5). The gene copy number profiles of matched DCIS and IBC were similar in all 6 pairs, however we also identified gene copy number alterations restricted either to DCIS or IBC: 1q gain (IBC-5); 3p and 3q losses (DCIS-6); 12p homozygous deletion (DCIS-4). Single cell sequencing of two cases (3 and 4) revealed that the majority of cells from both DCIS and IBC were derived from a common precursor lineage with shared copy number losses and gains. Both sets of DCIS-IBC pairs in these cases displayed elements of a subclonal structure with dominant clones alongside genetically diverse derivatives as well as genetic heterogeneity reflected in variable copy number alterations and non-modal clones.
CONCLUSION: Synchronous DCIS and IBC share founder genetic events, but also harbor somatic genetic alterations restricted to either the DCIS or IBC components, demonstrating that although DCIS is a precursor of IBC, intra-tumor genetic heterogeneity is present at the DCIS stage. Changes in clonal composition likely take place in the progression from DCIS to IBC.
Citation Format: Rita A. Sakr, Luciano G. Martelotto, Timour Baslan, Charlotte KY Ng, Jude Kendall, Linda Rodgers, Hilary Cox, Mike Riggs, Sean D'Itali, Asya Stepansky, Narciso Olvera, Tari A. King, Britta Weigelt, Jorge S. Reis-Filho, James Hicks. Intra-tumor heterogeneity and clonal changes in the progression of DCIS to invasiveness: Combined tumor bulk and single cell analysis. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2989. doi:10.1158/1538-7445.AM2015-2989
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Optimizing sparse sequencing of single cells for highly multiplex copy number profiling. Genome Res 2015; 25:714-24. [PMID: 25858951 PMCID: PMC4417119 DOI: 10.1101/gr.188060.114] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Accepted: 03/19/2015] [Indexed: 12/12/2022]
Abstract
Genome-wide analysis at the level of single cells has recently emerged as a powerful tool to dissect genome heterogeneity in cancer, neurobiology, and development. To be truly transformative, single-cell approaches must affordably accommodate large numbers of single cells. This is feasible in the case of copy number variation (CNV), because CNV determination requires only sparse sequence coverage. We have used a combination of bioinformatic and molecular approaches to optimize single-cell DNA amplification and library preparation for highly multiplexed sequencing, yielding a method that can produce genome-wide CNV profiles of up to a hundred individual cells on a single lane of an Illumina HiSeq instrument. We apply the method to human cancer cell lines and biopsied cancer tissue, thereby illustrating its efficiency, reproducibility, and power to reveal underlying genetic heterogeneity and clonal phylogeny. The capacity of the method to facilitate the rapid profiling of hundreds to thousands of single-cell genomes represents a key step in making single-cell profiling an easily accessible tool for studying cell lineage.
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QTc prolongation and treatment of multidrug-resistant tuberculosis. Int J Tuberc Lung Dis 2015; 19:385-91. [DOI: 10.5588/ijtld.14.0335] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Large-scale discovery of novel genetic causes of developmental disorders. Nature 2015; 519:223-8. [PMID: 25533962 PMCID: PMC5955210 DOI: 10.1038/nature14135] [Citation(s) in RCA: 773] [Impact Index Per Article: 85.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Accepted: 12/04/2014] [Indexed: 12/23/2022]
Abstract
Despite three decades of successful, predominantly phenotype-driven discovery of the genetic causes of monogenic disorders, up to half of children with severe developmental disorders of probable genetic origin remain without a genetic diagnosis. Particularly challenging are those disorders rare enough to have eluded recognition as a discrete clinical entity, those with highly variable clinical manifestations, and those that are difficult to distinguish from other, very similar, disorders. Here we demonstrate the power of using an unbiased genotype-driven approach to identify subsets of patients with similar disorders. By studying 1,133 children with severe, undiagnosed developmental disorders, and their parents, using a combination of exome sequencing and array-based detection of chromosomal rearrangements, we discovered 12 novel genes associated with developmental disorders. These newly implicated genes increase by 10% (from 28% to 31%) the proportion of children that could be diagnosed. Clustering of missense mutations in six of these newly implicated genes suggests that normal development is being perturbed by an activating or dominant-negative mechanism. Our findings demonstrate the value of adopting a comprehensive strategy, both genome-wide and nationwide, to elucidate the underlying causes of rare genetic disorders.
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Impact of reduced hospitalisation on the cost of treatment for drug-resistant tuberculosis in South Africa. Int J Tuberc Lung Dis 2015; 19:172-8. [PMID: 25574915 PMCID: PMC4447891 DOI: 10.5588/ijtld.14.0421] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
SETTING The cost of multidrug-resistant tuberculosis (MDR-TB) treatment is a major barrier to treatment scale-up in South Africa. OBJECTIVE To estimate and compare the cost of treatment for rifampicin-resistant tuberculosis (RR-TB) in South Africa in different models of care in different settings. DESIGN We estimated the costs of different models of care with varying levels of hospitalisation. These costs were used to calculate the total cost of treating all diagnosed cases of RR-TB in South Africa, and to estimate the budget impact of adopting a fully or partially decentralised model vs. a fully hospitalised model. RESULTS The fully hospitalised model was 42% more costly than the fully decentralised model (US$13,432 vs. US$7753 per patient). A much shorter hospital stay in the decentralised models of care (44-57 days), compared to 128 days of hospitalisation in the fully hospitalised model, was the key contributor to the reduced cost of treatment. The annual total cost of treating all diagnosed cases ranged from US$110 million in the fully decentralised model to US$190 million in the fully hospitalised model. CONCLUSION Following a more decentralised approach for treating RR-TB patients could potentially improve the affordability of RR-TB treatment in South Africa.
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Community-based treatment of drug-resistant tuberculosis in Khayelitsha, South Africa. Int J Tuberc Lung Dis 2014; 18:441-8. [DOI: 10.5588/ijtld.13.0742] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Use of complementary markers in assessing glycaemic control in people with diabetic kidney disease undergoing iron or erythropoietin treatment. Diabet Med 2013; 30:1250-4. [PMID: 23758176 DOI: 10.1111/dme.12249] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Revised: 04/29/2013] [Accepted: 06/06/2013] [Indexed: 11/28/2022]
Abstract
AIMS HbA(1c) values are unreliable in patients with diabetes who have chronic kidney disease who receive iron and/or erythropoiesis stimulating agents. The study aimed to evaluate the utility of the complementary glycaemic markers glycated albumin, fructosamine and 1,5 anhydroglucitol in this group of patients. METHODS A prospective study of patients with Type 2 diabetes and chronic kidney disease stage IIIB/IV undergoing intravenous iron or erythropoiesis-stimulating agent therapy. Glycaemic control was monitored using HbA(1c), seven-point daily glucose thrice weekly, continuous glucose monitoring, glycated albumin, fructosamine and 1,5 anhydroglucitol. RESULTS Fifteen patients [9 men; median age 72 years (interquartile range 68-74), follow-up period (16.4 ± 3.7 weeks)] received parenteral iron; 15 patients [11 men; 70 years (interquartile range 62-75), (17.3 ± 3.3 weeks)] received erythropoiesis-stimulating agent. HbA(1c) fell following treatment with both iron [57 mmol/mol (7.4%) to 53 mmol/mol (7.0%), P < 0.001] and erythropoiesis-stimulating agent [56 mmol/mol (7.3%) to 49 mmol/mol (6.6%), P = 0.01] despite mean blood glucose remaining unchanged (iron: 9.55 to 9.71 mmol/l, P = 0.07; erythropoiesis-stimulating agent: 8.72 to 8.78 mmol/l, P = 0.89). Unlike HbA1c , the glycated albumin, fructosamine and 1,5 anhydroglucitol levels did not change following iron [glycated albumin (16.8 to 16.3%, P = 0.10); fructosamine (259.5 to 256 μmol/l, P = 0.89); 1,5 anhydroglucitol (54.2 to 50.9 μmol/l, P = 0.89)] or erythropoiesis-stimulating agent [glycated albumin (17.9 to 17.5%, P = 0.29), fructosamine (324.3 to 306.0 μmol/l, P = 0.52), 1,5 anhydroglucitol (58.2 to 46.7 μmol/l, P = 0.35)]. Despite this, HbA(1c) was consistently the marker most closely related to mean blood glucose before and after each treatment (R range 0.7-0.88). CONCLUSIONS These data indicate that HbA(1c) was statistically most closely related to mean blood glucose, but clinical trends in glycaemia in patients undergoing iron or erythropoiesis-stimulating agent therapy are likely best assessed by including one of these additional glycaemic markers.
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Preventive Therapy for Child Contacts of Multidrug-Resistant Tuberculosis: A Prospective Cohort Study. Clin Infect Dis 2013; 57:1676-84. [DOI: 10.1093/cid/cit655] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Strategies for reducing treatment default in drug-resistant tuberculosis: systematic review and meta-analysis [Review article]. Int J Tuberc Lung Dis 2013; 17:299-307. [DOI: 10.5588/ijtld.12.0537] [Citation(s) in RCA: 104] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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P98. The cost of consumables in the surgical management of breast cancer. Eur J Surg Oncol 2012. [DOI: 10.1016/j.ejso.2012.07.219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Linezolid for the treatment of complicated drug-resistant tuberculosis: a systematic review and meta-analysis. Int J Tuberc Lung Dis 2012; 16:447-54. [PMID: 22325685 DOI: 10.5588/ijtld.11.0451] [Citation(s) in RCA: 110] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Current treatment for drug-resistant tuberculosis (DR-TB) is inadequate, and outcomes are significantly poorer than for drug-susceptible TB, particularly for patients previously treated with second-line drugs, treatment failures or extensively drug-resistant (XDR-) TB patients (complicated DR-TB). Linezolid is not recommended for routine DR-TB treatment due to the lack of efficacy data, but is suggested for patients where adequate second-line regimens are difficult to design. OBJECTIVE To conduct a systematic review and meta-analysis to assess existing evidence of efficacy and safety of linezolid for DR-TB treatment. METHODS We searched PubMed, Embase and abstracts from World Conferences of The Union for studies published through February 2011. We included all studies in which linezolid was given systematically to DR-TB patients and where treatment outcomes were reported. RESULTS A total of 11 studies were included in our review, representing 148 patients. The pooled proportion for treatment success was 67.99% (95%CI 58.00-78.99, τ2 129.42). There were no significant differences in success comparing daily linezolid dose (≤600 vs. >600 mg) and mean linezolid duration (≤7 vs. >7 months). The pooled estimate for the frequency of any adverse events was 61.48% (95%CI 40.15-82.80), with 36.23% (95%CI 20.67-51.79) discontinuing linezolid due to adverse events. CONCLUSION Treatment success with linezolid was equal to or better than that commonly achieved for uncomplicated DR-TB, and better than previous reports for previously treated patients and those with XDR-TB. While data are limited, linezolid appears be a useful drug, albeit associated with significant adverse events, and should be considered in the treatment of complicated DR-TB.
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Abstract
Defects at the level of pre-mRNA splicing are a common source of genetic mutation but such mutations are not always easy to identify from DNA sequence data alone. Clinical practice has only recently begun to incorporate analysis for this type of abnormality. Some base changes at the DNA level currently viewed as unclassified variants or missense mutations may influence RNA splicing. To address this problem for fibrillin 1 (FBN1) gene missense mutations we have carried out RNA analysis and in silico analysis with splice site prediction programs on 40 cases with 36 different mutations. Direct analysis of RNA from blood was performed by cDNA preparation, PCR amplification of specific FBN1 fragments, gel electrophoresis and sequencing of the PCR products. Of the 36 missense base changes, direct RNA analysis identified 2 which caused an abnormality of splicing. In silico analysis using five splice site prediction programs did not always accurately predict the splicing seen by direct RNA analysis. In conclusion, some apparent missense mutations have an effect on splicing which can be identified by direct RNA analysis, however, in silico analysis of splice sites is not always accurate, should be carried out with more than one prediction program and results should be used with caution.
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A national audit of pollen immunotherapy for children in the United Kingdom: patient selection and programme safety. Clin Exp Allergy 2011; 41:1313-23. [PMID: 21762222 DOI: 10.1111/j.1365-2222.2011.03803.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND Specific immunotherapy (SIT) is an effective treatment for grass and/or tree pollen-induced severe allergic rhinoconjunctivitis. However, there are limited detailed data on the use of immunotherapy in children in the United Kingdom. OBJECTIVES We audited NHS paediatric practice against current national guidelines to evaluate patient selection, SIT modalities and adverse events (AEs). METHODS Paediatricians offering pollen SIT were identified through the British Society of Allergy and Clinical Immunology Paediatric Allergy Group (BSACI-PAG) and the database of SIT providers compiled for the Royal College of Physicians and Royal College of Pathologists 2010 joint working group. Standardized proformas were returned by 12 of 20 centres (60%), including 12 of 14 centres offering subcutaneous immunotherapy (SCIT) (85%). RESULTS Three hundred and twenty-three children, with mean age 11 years at initiation (69% boys), had undergone 528 SIT cycles (SCIT 31%) over 10 years. Fifty-five percent of all patients had asthma. Among SCIT programmes 24.5% patients had perennial (± seasonal) asthma; 75.6% of asthmatics undertaking SCIT had treatments at BTS/SIGN step 2 or above. AEs occurred frequently (50.4% of all SIT cycles) but were mild. In sublingual immunotherapy (SLIT) treatment, local intraoral immediate reactions were most common (44.9% SLIT cycles), as compared with delayed reactions around the injection site in SCIT (28.3% SCIT cycles). An asthma diagnosis had no impact on the number of cycles with AEs, or the severity reported. Few cycles (2.9%) were discontinued as a result of AE(s). CONCLUSIONS AND CLINICAL RELEVANCE Pollen SIT is available across England, though small numbers of children are being treated. Current national guidelines to exclude asthmatic children in SIT programmes are not being adhered to by most specialist paediatric allergy centres. SCIT and SLIT has been well tolerated. Review of patient selection criteria is needed and may allow greater use of this therapeutic option in appropriate clinical settings.
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P190 The usefulness of an education pathway in supporting cardiac nurses continuing professional development. Eur J Cardiovasc Nurs 2011. [DOI: 10.1016/s1474-5151(11)60144-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Interstitial microduplication of Xp22.31: Causative of intellectual disability or benign copy number variant? Eur J Med Genet 2010; 53:93-9. [PMID: 20132918 DOI: 10.1016/j.ejmg.2010.01.004] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2009] [Accepted: 01/23/2010] [Indexed: 12/16/2022]
Abstract
The use of comparative genomic hybridization (CGH) and single nucleotide polymorphism (SNP) arrays has dramatically altered the approach to identification of genetic alterations that can explain intellectual disability and /or congenital anomalies. However, the discovery of numerous copy number changes with benign or unknown clinical significance has made interpretation problematic. Submicroscopic duplication of Xp22.31 has been reported as either a possible cause of intellectual disability and/or developmental delay or a benign variant. Here we report 29 individuals with the microduplication found as part of microarray analysis of 7793 samples submitted to an international group of 13 clinical laboratories. The referral reasons varied and included developmental delay, intellectual disability, autism, dysmorphic features and/or multiple congenital anomalies. The size of the Xp22.31 duplication varied between 149 kb and 1.74 Mb and included the steroid sulfatase (STS) gene with the male to female ratio of 0.7. Duplication within this segment is seen at a frequency of 0.15% in a healthy control population, whereas a frequency of 0.37% was observed in our cohort of individuals with abnormal phenotypes. We present a detailed comparison of the breakpoints, inheritance, X-inactivation and clinical phenotype in our cohort and a review of the literature for a total of 41 patients. To date, this report is the largest compilation of clinical and array data regarding the microduplication of Xp22.31 and will serve to broaden the knowledge of regions involving copy number variation (CNV).
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Fragile x mental retardation 1 and filamin a interact genetically in Drosophila long-term memory. Front Neural Circuits 2010; 3:22. [PMID: 20190856 PMCID: PMC2813723 DOI: 10.3389/neuro.04.022.2009] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2009] [Accepted: 12/03/2009] [Indexed: 11/13/2022] Open
Abstract
The last decade has witnessed the identification of single-gene defects associated with an impressive number of mental retardation syndromes. Fragile X syndrome, the most common cause of mental retardation for instance, results from disruption of the FMR1 gene. Similarly, Periventricular Nodular Heterotopia, which includes cerebral malformation, epilepsy and cognitive disabilities, derives from disruption of the Filamin A gene. While it remains unclear whether defects in common molecular pathways may underlie the cognitive dysfunction of these various syndromes, defects in cytoskeletal structure nonetheless appear to be common to several mental retardation syndromes. FMR1 is known to interact with Rac, profilin, PAK and Ras, which are associated with dendritic spine defects. In Drosophila, disruptions of the dFmr1 gene impair long-term memory (LTM), and the Filamin A homolog (cheerio) was identified in a behavioral screen for LTM mutants. Thus, we investigated the possible interaction between cheerio and dFmr1 during LTM formation in Drosophila. We show that LTM specifically is defective in dFmr1/cheerio double heterozygotes, while it is normal in single heterozygotes for either dFmr1 or cheerio. In dFmr1 mutants, Filamin (Cheerio) levels are lower than normal after spaced training. These observations support the notion that decreased actin cross-linking may underlie the persistence of long and thin dendritic spines in Fragile X patients and animal models. More generally, our results represent the first demonstration of a genetic interaction between mental retardation genes in an in vivo model system of memory formation.
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Excess protein synthesis in Drosophila fragile X mutants impairs long-term memory. Nat Neurosci 2008; 11:1143-5. [PMID: 18776892 PMCID: PMC3038669 DOI: 10.1038/nn.2175] [Citation(s) in RCA: 167] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2008] [Accepted: 06/27/2008] [Indexed: 12/18/2022]
Abstract
We used Drosophila olfactory memory in order to understand in vivo the molecular basis of cognitive defect in Fragile X syndrome. We observed that Fragile X protein (FMRP) was required acutely and interacted with argonaute1 and staufen in long-term memory (LTM). Occlusion of long-term memory formation in Fragile X mutants could be rescued by protein synthesis inhibitors, suggesting that excess baseline protein synthesis could impact negatively on cognition.
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The investigation of chronic urticaria in childhood: which investigations are being performed and which are recommended? Clin Exp Allergy 2008; 38:1061-2. [DOI: 10.1111/j.1365-2222.2008.02975.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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A brief cognitive behavioural preimplantation and rehabilitation programme for patients receiving an implantable cardioverter-defibrillator improves physical health and reduces psychological morbidity and unplanned readmissions. Heart 2007; 95:63-9. [PMID: 18070951 DOI: 10.1136/hrt.2007.129890] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
OBJECTIVE To assess the clinical and cost effectiveness of a brief home-based cognitive behavioural rehabilitation programme (the ICD Plan) for patients undergoing implantation of a cardiac defibrillator. DESIGN A prospective multicentred, intention-to-treat, cluster-randomised controlled trial. SETTING Eight implantable cardioverter-defibrillator (ICD) implantation centres in the UK. PATIENTS Consecutive series of patients undergoing implantation with an ICD. INTERVENTIONS The control group received usual care and advice from an experienced healthcare professional. The intervention group received usual care plus the ICD Plan. The plan was introduced before implantation, with three further brief telephone contacts with the nurse over the next 12 weeks. MAIN OUTCOME MEASURES Health-related quality of life (Short Form Health Survey (SF-12)), anxiety and depression (Hospital Anxiety and Depression Scale (HADS)), activity limitations (subscale from the Seattle Angina Questionnaire (SAQ)), unplanned admissions and other economic data using a questionnaire developed for the study. RESULTS 192 patients were recruited to the study (71 intervention, 121 control). At 6 months after surgery the intervention group had better physical health (37.83 vs 34.24; p<0.01), fewer limitations in physical activity (34.02 vs 31.72; p = 0.04), a greater reduction in the proportion of patients with a borderline diagnosis of anxiety (21% vs 13%; p = 0.60) and depression (13% vs 2%; p = 0.30), more planned ECGs (89% vs 66%; p = 0.04) and 50% fewer unplanned admissions (11% vs 22%; p<0.01). CONCLUSIONS The ICD Plan improved health-related quality of life, reduced the incidence of clinically significant psychological distress and significantly reduced unplanned readmissions. It is a cost effective and easily implemented method for delivering rehabilitation and psychological care to patients undergoing ICD implantation. TRIAL REGISTRATION NUMBER ISRCTN70212111.
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Abstracts of presentations to the Annual Meetings of the Canadian Society of Colon and Rectal Surgeons Canadian Association of General Surgeons Canadian Association of Thoracic Surgeons: Canadian Surgery Forum, Toronto, Ont., September 6-9, 2007. Can J Surg 2007; 50:1-32. [PMID: 37353894 PMCID: PMC10390043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/25/2023] Open
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Injections for health-related reasons amongst injecting drug users in New Delhi and Imphal, India. Public Health 2006; 120:634-40. [PMID: 16753193 DOI: 10.1016/j.puhe.2006.01.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2005] [Revised: 10/04/2005] [Accepted: 01/31/2006] [Indexed: 11/30/2022]
Abstract
OBJECTIVES In many parts of the world where unsafe injection practices in health settings are common, the prevalence of blood-borne viruses (BBVs) is high amongst injecting drug users (IDUs). If IDUs in these settings are receiving injections for health-related reasons, the possibility of amplification of BBV transmission via medical injections exists. The aim of this study is to describe the nature and extent of injections received for health-related reasons amongst IDUs in two Indian cities, New Delhi and Imphal. METHODS A cross-sectional survey of 200 IDUs was conducted in late 2004. Trained peer outreach workers asked participants about health problems experienced, consultations with healthcare providers and health-related injections received in the preceding 4 weeks. RESULTS Most participants (99.5%) were male, the average age was 29 years, and the average time since first injection of illicit drugs was 6 years. A total of 133 injections were received for health-related reasons during the preceding 4 weeks by 15% of the participants. The average number of injections was 8.6/participant/year. CONCLUSION Injections for health-related reasons were commonplace amongst these IDUs. Therefore, amplification of BBV transmission within communities due to unsafe injections is possible and warrants further investigation.
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