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1.
Annu Rev Biochem ; 86: 277-304, 2017 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-28654323

RESUMO

Metabolites are the small biological molecules involved in energy conversion and biosynthesis. Studying metabolism is inherently challenging due to metabolites' reactivity, structural diversity, and broad concentration range. Herein, we review the common pitfalls encountered in metabolomics and provide concrete guidelines for obtaining accurate metabolite measurements, focusing on water-soluble primary metabolites. We show how seemingly straightforward sample preparation methods can introduce systematic errors (e.g., owing to interconversion among metabolites) and how proper selection of quenching solvent (e.g., acidic acetonitrile:methanol:water) can mitigate such problems. We discuss the specific strengths, pitfalls, and best practices for each common analytical platform: liquid chromatography-mass spectrometry (LC-MS), gas chromatography-mass spectrometry (GC-MS), nuclear magnetic resonance (NMR), and enzyme assays. Together this information provides a pragmatic knowledge base for carrying out biologically informative metabolite measurements.


Assuntos
Cromatografia Líquida/normas , Cromatografia Gasosa-Espectrometria de Massas/normas , Espectroscopia de Ressonância Magnética/normas , Espectrometria de Massas/normas , Metabolômica/normas , Trifosfato de Adenosina/análise , Animais , Glutationa/análise , Guias como Assunto , Humanos , Microextração em Fase Líquida/métodos , Metabolômica/instrumentação , Metabolômica/métodos , Camundongos , NADP/análise , Solventes
2.
Blood ; 142(17): 1448-1462, 2023 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-37595278

RESUMO

Hematopoietic stem and progenitor cells (HSPCs) rely on a complex interplay among transcription factors (TFs) to regulate differentiation into mature blood cells. A heptad of TFs (FLI1, ERG, GATA2, RUNX1, TAL1, LYL1, LMO2) bind regulatory elements in bulk CD34+ HSPCs. However, whether specific heptad-TF combinations have distinct roles in regulating hematopoietic differentiation remains unknown. We mapped genome-wide chromatin contacts (HiC, H3K27ac, HiChIP), chromatin modifications (H3K4me3, H3K27ac, H3K27me3) and 10 TF binding profiles (heptad, PU.1, CTCF, STAG2) in HSPC subsets (stem/multipotent progenitors plus common myeloid, granulocyte macrophage, and megakaryocyte erythrocyte progenitors) and found TF occupancy and enhancer-promoter interactions varied significantly across cell types and were associated with cell-type-specific gene expression. Distinct regulatory elements were enriched with specific heptad-TF combinations, including stem-cell-specific elements with ERG, and myeloid- and erythroid-specific elements with combinations of FLI1, RUNX1, GATA2, TAL1, LYL1, and LMO2. Furthermore, heptad-occupied regions in HSPCs were subsequently bound by lineage-defining TFs, including PU.1 and GATA1, suggesting that heptad factors may prime regulatory elements for use in mature cell types. We also found that enhancers with cell-type-specific heptad occupancy shared a common grammar with respect to TF binding motifs, suggesting that combinatorial binding of TF complexes was at least partially regulated by features encoded in DNA sequence motifs. Taken together, this study comprehensively characterizes the gene regulatory landscape in rare subpopulations of human HSPCs. The accompanying data sets should serve as a valuable resource for understanding adult hematopoiesis and a framework for analyzing aberrant regulatory networks in leukemic cells.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core , Células-Tronco Hematopoéticas , Humanos , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Regulação da Expressão Gênica , Hematopoese/genética , Cromatina/metabolismo
3.
Anal Chem ; 96(17): 6566-6574, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38642077

RESUMO

Quantitative liquid chromatography-mass spectrometry (LC-MS)-based metabolomics is becoming an important approach for studying complex biological systems but presents several technical challenges that limit its widespread use. Computing metabolite concentrations using standard curves generated from standard mixtures of known concentrations is a labor-intensive process that is often performed manually. Currently, there are few options for open-source software tools that can automatically calculate metabolite concentrations. Herein, we introduce SCALiR (standard curve application for determining linear ranges), a new web-based software tool specifically built for this task, which allows users to automatically transform LC-MS signals into absolute quantitative data (https://www.lewisresearchgroup.org/software). SCALiR uses an algorithm that automatically finds the equation of the line of best fit for each standard curve and uses this equation to calculate compound concentrations from the LC-MS signal. Using a standard mix containing 77 metabolites, we show a close correlation between the concentrations calculated by SCALiR and the expected concentrations of each compound (R2 = 0.99 for a y = x curve fitting). Moreover, we demonstrate that SCALiR reproducibly calculates concentrations of midrange standards across ten analytical batches (average coefficient of variation 0.091). SCALiR can be used to calculate metabolite concentrations either using external calibration curves or by using internal standards to correct for matrix effects. This open-source and vendor agnostic software offers users several advantages in that (1) it requires only 10 s of analysis time to compute concentrations of >75 compounds, (2) it facilitates automation of quantitative workflows, and (3) it performs deterministic evaluations of compound quantification limits. SCALiR therefore provides the metabolomics community with a simple and rapid tool that enables rigorous and reproducible quantitative metabolomics studies.


Assuntos
Espectrometria de Massas , Metabolômica , Software , Metabolômica/métodos , Espectrometria de Massas/métodos , Cromatografia Líquida/métodos , Internet , Algoritmos , Automação , Animais
4.
Anal Chem ; 96(8): 3382-3388, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38359900

RESUMO

Metabolomics is a powerful tool for uncovering biochemical diversity in a wide range of organisms. Metabolic network modeling is commonly used to frame metabolomics data in the context of a broader biological system. However, network modeling of poorly characterized nonmodel organisms remains challenging due to gene homology mismatches which lead to network architecture errors. To address this, we developed the Metabolic Interactive Nodular Network for Omics (MINNO), a web-based mapping tool that uses empirical metabolomics data to refine metabolic networks. MINNO allows users to create, modify, and interact with metabolic pathway visualizations for thousands of organisms, in both individual and multispecies contexts. Herein, we illustrate the use of MINNO in elucidating the metabolic networks of understudied species, such as those of the Borrelia genus, which cause Lyme and relapsing fever diseases. Using a hybrid genomics-metabolomics modeling approach, we constructed species-specific metabolic networks for threeBorrelia species. Using these empirically refined networks, we were able to metabolically differentiate these species via their nucleotide metabolism, which cannot be predicted from genomic networks. Additionally, using MINNO, we identified 18 missing reactions from the KEGG database, of which nine were supported by the primary literature. These examples illustrate the use of metabolomics for the empirical refining of genetically constructed networks and show how MINNO can be used to study nonmodel organisms.


Assuntos
Metabolômica , Software , Genômica , Genoma , Redes e Vias Metabólicas
5.
Breast Cancer Res Treat ; 197(1): 39-49, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36319906

RESUMO

PURPOSE: A James Lind Alliance priority setting partnership was developed to identify research priorities in breast cancer surgery from individuals with lived experience, at high genetic risk of breast cancer, and healthcare professionals (HCPs). METHODS: 'Uncertainties' were collected using an online survey. Following an evidence check and development of summary questions, an interim survey asked participants to rank their top 10 research priorities from the question list. Top-ranked questions from patient/carer, high-risk and professional groups were carried forward for discussion to a final online prioritisation workshop. RESULTS: 260 participants (101 patients/carers, 156 HCPs) submitted 940 uncertainties via the initial survey. These were analysed thematically into 128 summary questions in six topic areas. Following evidence checking, 59 questions were included in the interim survey which was completed by 572 respondents. Marked differences were seen in questions prioritised by patients/carers, HCPs and women at high-risk. The top eight priorities in patient/carer and professional groups and top two priorities for high-risk women were carried forward to the online workshop at which 22 participants discussed and agreed the final top 10. Key themes included de-escalation of breast and axillary surgery, factors impacting the development/detection of locoregional recurrence and optimal provision of support for informed treatment decision-making. CONCLUSION: The top 10 research priorities in breast cancer surgery have been agreed. However, the observed differences in research priorities identified by patients and professional groups were not anticipated. Top priorities from both groups should inform future UK breast cancer surgical research, to ensure that it addresses questions that are important to breast cancer community as a whole.


Assuntos
Pesquisa Biomédica , Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/cirurgia , Prioridades em Saúde , Recidiva Local de Neoplasia , Inquéritos e Questionários , Reino Unido
6.
Anal Bioanal Chem ; 415(2): 269-276, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36443449

RESUMO

Liquid chromatography mass spectrometry (LC-MS) has emerged as a mainstream strategy for metabolomics analyses. One advantage of LC-MS is that it can serve both as a biomarker discovery tool and as a platform for clinical diagnostics. Consequently, it offers an exciting opportunity to potentially transition research studies into real-world clinical tools. One important distinction between research versus diagnostics-based applications of LC-MS is throughput. Clinical LC-MS must enable quantitative analyses of target molecules in hundreds or thousands of samples each day. Currently, the throughput of these clinical applications is limited by the chromatographic gradient lengths, which-when analyzing complex metabolomics samples-are difficult to conduct in under ~ 3 min per sample without introducing serious quantitative analysis problems. To address this shortcoming, we developed sequential quantification using isotope dilution (SQUID), an analytical strategy that combines serial sample injections into a continuous isocratic mobile phase to maximize throughput. SQUID uses internal isotope-labelled standards to correct for changes in LC-MS response factors over time. We show that SQUID can detect microbial polyamines in human urine specimens (lower limit of quantification; LLOQ = 106 nM) with less than 0.019 normalized root mean square error. Moreover, we show that samples can be analyzed in as little as 57 s. We propose SQUID as a new, high-throughput LC-MS tool for quantifying small sets of target biomarkers across large cohorts.


Assuntos
Metabolômica , Espectrometria de Massas em Tandem , Humanos , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida/métodos , Metabolômica/métodos , Biomarcadores/análise , Poliaminas
7.
Int Wound J ; 20(7): 2688-2699, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37203247

RESUMO

Skin tissue assessment is traditionally used to identify early signs of pressure damage from changes observed at the skin surface. However, the early onset of tissue damage induced by pressure and shear forces is likely to be on soft tissues beneath the surface of the skin. Subepidermal moisture (SEM) is a biophysical marker for the detection of early and deep pressure-induced tissue damage. Measurement of SEM can detect early pressure ulcers up to 5 days before visible skin changes occur. The aim of this study was to evaluate the cost-effectiveness of SEM measurement compared with visual skin assessment (VSA). A decision-tree model was developed. Outcomes are the incidence of hospital-acquired pressure ulcers, quality-adjusted life-years (QALYs) and costs to the UK National Health Service. Costs are at 2020/21 prices. The effects of parameter uncertainty are tested in univariate and probabilistic sensitivity analysis. In a representative NHS acute hospital, the incremental cost of SEM assessment as an adjunct to VSA is -£8.99 per admission, and SEM assessment is expected to reduce the incidence of hospital-acquired pressure ulcers by 21.1%, reduce NHS costs and lead to a gain of 3.634 QALYs. The probability of cost-effectiveness at a threshold of £30 000 per quality-adjusted life year is 61.84%. Pathways that include SEM assessment make it possible to implement early and anatomy-specific interventions which have the potential to improve the effectiveness of pressure ulcer prevention and reduce healthcare costs.


Assuntos
Úlcera por Pressão , Humanos , Úlcera por Pressão/diagnóstico , Úlcera por Pressão/prevenção & controle , Úlcera por Pressão/epidemiologia , Análise Custo-Benefício , Medicina Estatal , Pele , Hospitais
8.
Anal Chem ; 94(25): 8874-8882, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35700271

RESUMO

Metabolomics is a mainstream approach for investigating the metabolic underpinnings of complex biological phenomena and is increasingly being applied to large-scale studies involving hundreds or thousands of samples. Although metabolomics methods are robust in smaller-scale studies, they can be challenging to apply to larger cohorts due to the inherent variability of liquid chromatography mass spectrometry (LC-MS). Much of this difficulty results from the time-dependent changes in the LC-MS system, which affects both the qualitative and quantitative performances of the instrument. Herein, we introduce an analytical strategy for addressing this problem in large-scale microbial studies. Our approach quantifies microbial boundary fluxes using two zwitterionic hydrophilic interaction liquid chromatography (ZIC-HILIC) columns that are plumbed to enable offline column equilibration. Using this strategy, we show that over 397 common metabolites can be resolved in 4.5 min per sample and that metabolites can be quantified with a median coefficient of variation of 0.127 across 1100 technical replicates. We illustrate the utility of this strategy via an analysis of 960 strains of Staphylococcus aureus isolated from bloodstream infections. These data capture the diversity of metabolic phenotypes observed in clinical isolates and provide an example of how large-scale investigations can leverage our novel analytical strategy.


Assuntos
Técnicas de Cultura de Células , Metabolômica , Cromatografia Líquida/métodos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Espectrometria de Massas/métodos , Metabolômica/métodos
9.
FASEB J ; 35(5): e21513, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33811704

RESUMO

Human male reproductive development has a prolonged prepubertal period characterized by juvenile quiescence of germ cells with immature spermatogonial stem cell (SSC) precursors (gonocytes) present in the testis for an extended period of time. The metabolism of gonocytes is not defined. We demonstrate with mitochondrial ultrastructure studies via TEM and IHC and metabolic flux studies with UHPLC-MS that a distinct metabolic transition occurs during the maturation to SSCs. The mitochondrial ultrastructure of prepubertal human spermatogonia is shared with prepubertal pig spermatogonia. The metabolism of early prepubertal porcine spermatogonia (gonocytes) is characterized by the reliance on OXPHOS fuelled by oxidative decarboxylation of pyruvate. Interestingly, at the same time, a high amount of the consumed pyruvate is also reduced and excreted as lactate. With maturation, prepubertal spermatogonia show a metabolic shift with decreased OXHPOS and upregulation of the anaerobic metabolism-associated uncoupling protein 2 (UCP2). This shift is accompanied with stem cell specific promyelocytic leukemia zinc finger protein (PLZF) protein expression and glial cell-derived neurotropic factor (GDNF) pathway activation. Our results demonstrate that gonocytes differently from mature spermatogonia exhibit unique metabolic demands that must be attained to enable their maintenance and growth in vitro.


Assuntos
Regulação da Expressão Gênica , Células Germinativas/metabolismo , Estresse Oxidativo , Células-Tronco/metabolismo , Testículo/metabolismo , Animais , Células Germinativas/citologia , Glicólise , Humanos , Masculino , Potencial da Membrana Mitocondrial , Fenótipo , Células-Tronco/citologia , Suínos , Testículo/citologia
10.
Brain Behav Immun ; 102: 266-278, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35259427

RESUMO

Inflammatory bowel diseases (IBD) are chronic inflammatory conditions of the gastrointestinal tract. IBD are associated with a high prevalence of cognitive, behavioural and emotional comorbidities, including anxiety and depression. The link between IBD and the development of behavioural comorbidities is poorly understood. As the intestinal microbiota profoundly influences host behaviour, we sought to determine whether the altered gut microbiota associated with intestinal inflammation contributes to the development of behavioural abnormalities. Using the dextran sulphate sodium (DSS) model of colitis, we characterized intestinal inflammation, behaviour (elevated plus maze and tail suspension test) and the composition of the microbiota in male mice. Cecal contents from colitic mice were transferred into germ-free (GF) or antibiotic (Abx)-treated mice, and behaviour was characterized in recipient mice. Gene expression was measured using qPCR. DSS colitis was characterized by a significant reduction in body weight and an increase in colonic inflammatory markers. These changes were accompanied by increased anxiety-like behaviour, an altered gut microbiota composition, and increased central Tnf expression. Transfer of the cecal matter from colitic mice induced similar behavioural changes in both GF and Abx-treated recipient mice, with no signs of colonic or neuroinflammation. Upon characterization of the microbiota in donor and recipient mice, specific taxa were found to be associated with behavioural changes, notably members of the Lachnospiraceae family. Behavioural abnormalities associated with intestinal inflammation are transmissible via transfer of cecal matter, suggesting that alterations in the composition of the gut microbiota play a key role in driving behavioural changes in colitis.


Assuntos
Colite , Doenças Inflamatórias Intestinais , Microbiota , Animais , Colite/induzido quimicamente , Sulfato de Dextrana/farmacologia , Modelos Animais de Doenças , Inflamação , Masculino , Camundongos , Camundongos Endogâmicos C57BL
11.
Anal Bioanal Chem ; 414(2): 969-991, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34668998

RESUMO

Biopharmaceuticals have revolutionized the field of medicine in the types of active ingredient molecules and treatable indications. Adoption of Quality by Design and Process Analytical Technology (PAT) frameworks has helped the biopharmaceutical field to realize consistent product quality, process intensification, and real-time control. As part of the PAT strategy, Raman spectroscopy offers many benefits and is used successfully in bioprocessing from single-cell analysis to cGMP process control. Since first introduced in 2011 for industrial bioprocessing applications, Raman has become a first-choice PAT for monitoring and controlling upstream bioprocesses because it facilitates advanced process control and enables consistent process quality. This paper will discuss new frontiers in extending these successes in upstream from scale-down to commercial manufacturing. New reports concerning the use of Raman spectroscopy in the basic science of single cells and downstream process monitoring illustrate industrial recognition of Raman's value throughout a biopharmaceutical product's lifecycle. Finally, we draw upon a nearly 90-year history in biological Raman spectroscopy to provide the basis for laboratory and in-line measurements of protein quality, including higher-order structure and composition modifications, to support formulation development.


Assuntos
Produtos Biológicos/análise , Análise Espectral Raman/métodos , Tecnologia Farmacêutica/métodos , Controle de Qualidade , Espectroscopia de Luz Próxima ao Infravermelho/métodos
12.
Lancet Oncol ; 22(10): e435-e445, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34592193

RESUMO

The 2013 SPIRIT (Standard Protocol Items: Recommendations for Interventional Trials) Statement provides evidence-based recommendations for the minimum content to be included in a clinical trial protocol. Assessment of biospecimens is often required for trial eligibility or as part of an outcome evaluation, and precision molecular approaches are increasingly used in trial design. However, cellular and molecular pathology practices within trials have not been codified or formalised. We developed international consensus reporting guidelines for cellular and molecular pathology content in clinical trial protocols (the SPIRIT-Path extension) using an international Delphi process, which assesses candidate items generated from a previous systematic review, followed by an expert consensus meeting. 74 individuals from five continents responded, including clinicians, statisticians, laboratory scientists, patient advocates, funders, industry representatives, journal editors, and regulators. The SPIRIT-Path guidelines recommend 14 additional items (seven extensions to the SPIRIT checklist and seven elaborations) that should be addressed in trial protocols containing pathology content, alongside the SPIRIT 2013 Statement items. SPIRIT-Path recommends that protocols should document the individuals, processes, and standards for all cellular and molecular pathology components of the trial, including all stages of the specimen pathway and any digital pathology methods, with specific consideration of the value of trial data and biological tissues for additional translational studies.


Assuntos
Protocolos de Ensaio Clínico como Assunto , Ensaios Clínicos como Assunto/normas , Patologia Molecular/normas , Projetos de Pesquisa/normas , Lista de Checagem , Consenso , Técnica Delphi , Humanos
13.
J Biol Chem ; 295(34): 11949-11962, 2020 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-32601062

RESUMO

Pel is a GalNAc-rich bacterial polysaccharide that contributes to the structure and function of Pseudomonas aeruginosa biofilms. The pelABCDEFG operon is highly conserved among diverse bacterial species, and Pel may therefore be a widespread biofilm determinant. Previous annotation of pel gene clusters has helped us identify an additional gene, pelX, that is present adjacent to pelABCDEFG in >100 different bacterial species. The pelX gene is predicted to encode a member of the short-chain dehydrogenase/reductase (SDR) superfamily, but its potential role in Pel-dependent biofilm formation is unknown. Herein, we have used Pseudomonas protegens Pf-5 as a model to elucidate PelX function as Pseudomonas aeruginosa lacks a pelX homologue in its pel gene cluster. We found that P. protegens forms Pel-dependent biofilms; however, despite expression of pelX under these conditions, biofilm formation was unaffected in a ΔpelX strain. This observation led us to identify a pelX paralogue, PFL_5533, which we designate here PgnE, that appears to be functionally redundant to pelX In line with this, a ΔpelX ΔpgnE double mutant was substantially impaired in its ability to form Pel-dependent biofilms. To understand the molecular basis for this observation, we determined the structure of PelX to 2.1 Å resolution. The structure revealed that PelX resembles UDP-GlcNAc C4-epimerases. Using 1H NMR analysis, we show that PelX catalyzes the epimerization between UDP-GlcNAc and UDP-GalNAc. Our results indicate that Pel-dependent biofilm formation requires a UDP-GlcNAc C4-epimerase that generates the UDP-GalNAc precursors required by the Pel synthase machinery for polymer production.


Assuntos
Proteínas de Bactérias/metabolismo , Biofilmes , Carboidratos Epimerases/metabolismo , Polissacarídeos Bacterianos/metabolismo , Pseudomonas aeruginosa/fisiologia , Pseudomonas/fisiologia , Proteínas de Bactérias/genética , Carboidratos Epimerases/genética , Polissacarídeos Bacterianos/genética , Uridina Difosfato N-Acetilglicosamina/genética , Uridina Difosfato N-Acetilglicosamina/metabolismo
14.
Eur J Cancer Care (Engl) ; 30(5): e13448, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33774876

RESUMO

OBJECTIVE: The objective of this exploratory study was to determine the presence and correlates of self-reported cognition in a sample of haematological cancer patients who had undergone allogeneic stem cell transplantation (SCT). METHODS: Haematological cancer patients (n = 30) who had undergone allogeneic SCT between one and five years previously and age-matched control participants (n = 30) completed questionnaires assessing cognition, affect, sleep quality and fatigue and an assessment of premorbid IQ. RESULTS: Patients reported significantly poorer perceived cognitive ability (d = 1.12) and greater perceived cognitive impairment (d = 0.96) than controls. Lower fatigue was significantly associated with greater perceived cognitive ability (r = 0.75 patients and controls) and less perceived cognitive impairment (r = 0.80 patients; r = 0.57 controls). Interestingly, depression was significantly correlated with perceived cognitive ability in the control group only (r = 0.80). Hierarchical multiple regressions showed that fatigue was a significant predictor of perceived cognitive ability in patients, accounting for 56% of the variance. CONCLUSIONS: This study established that self-reported cognitive ability and cognitive impairment was significantly poorer in haematological cancer patients than controls. Furthermore, fatigue was significantly associated with perceived cognitive ability in patients. Future research should focus on identifying interventions that target fatigue in allogeneic SCT recipients in order to improve quality of life throughout survivorship.


Assuntos
Neoplasias Hematológicas , Transplante de Células-Tronco Hematopoéticas , Cognição , Fadiga/etiologia , Neoplasias Hematológicas/terapia , Humanos , Qualidade de Vida
15.
S Afr J Psychiatr ; 27: 1524, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33604071

RESUMO

BACKGROUND: Although there is a growing body of literature on the epidemiology of deliberate self-harm (DSH) in South Africa, comparatively few studies have investigated the motives for self-harm. No studies have investigated the motives for DSH in Cape Town. AIM: The objective of the study was to identify the range of motives for DSH in Cape Town, and how these motives are associated with different socio-demographic factors, the severity of self-injury and levels of suicidal intent. SETTING: Groote Schuur Hospital in Cape Town, South Africa. METHODS: Data were collected from 238 consecutive patients presenting with DSH to the emergency department. The data were analysed by using bivariate and multivariate analyses. RESULTS: Patients engaged in DSH for a range of motives. Interpersonal issues were the most common motive (70%), followed by financial concerns (22%). Male patients were twice as likely as female patients to report interpersonal motives for their self-harm. Patients who reported interpersonal issues were more likely to engage in methods of DSH that involved damage to body tissues. Patients without tertiary education were more likely to report academic concerns as a motive, and patients who reported psychiatric illness as motive for DSH were more likely to require medical interventions than those who did not. CONCLUSION: This study contributes novel insights into the motives for DSH in the Cape Town context and provides the foundation for continued research on the subject. The study also gives impetus to the development of therapeutic interventions focussed on the motives for self-harm.

16.
Biol Blood Marrow Transplant ; 26(2): 421-427, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31627016

RESUMO

Hematopoietic stem cell transplantation (HSCT) recipients are vulnerable to invasive pneumococcal disease (IPD), with reported IPD rates ranging from 3.81 to 22.5/1000 HSCT. This IPD risk could relate to immunodeficiency, low vaccination uptake, and poor immunogenicity of pneumococcal polysaccharide vaccine (PPV). Literature comparing the clinical effectiveness of pneumococcal conjugate vaccination (PCV) and PPV after HSCT is limited. In this retrospective analysis of HSCT recipients at our center from 2004 to 2015, we evaluated vaccination uptake and compared IPD rates in patients receiving PPV (pre-2010 group) and PCV (post-2010 group). IPD was determined from microbiological results for all HSCT recipients from January 2004 to June 30, 2019. Eight hundred patients had a total of 842 HSCT events, including autologous HSCT (auto-HSCT; n = 562) and allogeneic HSCT (allo-HSCT; n = 280). More than 90% of the HSCT recipients were enrolled, and >93% of surviving HSCT recipients completed the vaccination protocol. Fifteen IPD episodes occurred in 13 patients between 2004 and June 30, 2019. Thirteen episodes occurred in the pre-2010 group, even though 9 of 13 (69%) serotyped isolates were covered by PPV. Two episodes occurred in the post-2010 group; neither serotype was covered by PCV. Thus, with PCV introduction, IPD rate was significantly reduced from 38.5/1000 unique HSCTs pre-2010 to 4.0/1000 unique HSCTs post-2010 (P < .001). A significant reduction was seen in both auto-HSCTs (from 29.4 to 3.1 /1000 unique auto-HSCTs; P = .011) and allo-HSCTs (from 58.3 to 5.6/1000 unique allo-HSCTs; P = .011). PCV demonstrated superior clinical effectiveness over PPV, highlighting its importance in preventing infectious complications after HSCT. Robust vaccination programs at transplantation centers are needed to optimize vaccination uptake and completion.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Vacinas Pneumocócicas , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Vacinação
17.
Int J Psychiatry Clin Pract ; 24(2): 163-172, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31928103

RESUMO

Objective: We aimed to describe patterns of substance use among patients admitted to an emergency psychiatric unit for non-fatal suicidal behaviour (NFSB) or another psychiatric reason and establish whether there were significant differences in patterns of substance use between the two groups.Methods: We employed a case-control design (N = 50) and collected data about participants' substance use in Cape Town, South Africa. Data were analysed using Chi-square and Mann-Whitney tests, factor analysis, and logistic regressions.Results: Prevalence of lifetime Alcohol Use Disorder (AUD) was 60% in the NFSB group and 28% in the control group. 12% of the NFSB group and 20% of the control group had a lifetime Tobacco Use Disorder. Prevalence of lifetime illicit Substance Use Disorder was 44% in the NFSB group and 60% in the control group. Hospital admission for NFSB was associated with: any past 24-hour alcohol use; quantity of past 24-hour alcohol use; quantity of past-month alcohol use; lifetime AUD; past 12-month AUD; and current AUD; and was not associated with the use of any other substances (p<.05). Past 12-month AUD was the best predictor of hospital admission for NFSB, controlling for, respectively, any past 24-hour alcohol use (aOR = 13.33, p = .023) and quantity of past 24-hour alcohol use (aOR = 9.01, p = .022)Conclusions: Patients admitted to emergency psychiatric units for NFSB have increased needs for the treatment of AUDs compared to patients admitted for another psychiatric emergency. Findings support calls for interventions to prevent NFSB among psychiatric patients with a history of AUD.Key pointsRates of substance use among patients admitted to emergency psychiatric units in South Africa were high compared to the general population.Hazardous alcohol use was uniquely associated with hospital admission for non-fatal suicidal behaviour compared to another psychiatric emergency.Tobacco use and illicit substance use were not associated with hospital admission for non-fatal suicidal behaviour compared to another psychiatric emergency.The association between hazardous alcohol use and hospital admission for non-fatal suicidal behaviour did not appear to be affected by demographic variables.Patients admitted to hospital for non-fatal suicidal behaviour have increased needs for the treatment of alcohol use disorders compared to other psychiatric patients.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Alcoolismo/epidemiologia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Serviços de Emergência Psiquiátrica/estatística & dados numéricos , Tentativa de Suicídio/estatística & dados numéricos , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , África do Sul/epidemiologia
18.
S Afr J Psychiatr ; 26: 1399, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32391183

RESUMO

BACKGROUND: Little is known about the methods of deliberate self-harm (DSH) in South Africa (SA), despite the importance of means restriction as a public health strategy to reduce the morbidity and mortality associated with self-harm. AIM: The aim of this study was to investigate the range of methods used in DSH and identify the socio-demographic and clinical factors associated with violent and non-violent methods of DSH among patients treated at a tertiary hospital in SA. SETTING: The study was conducted at an urban, tertiary level emergency department at Groote Schuur hospital in Cape Town, South Africa. METHOD: Data were collected from 238 consecutive DSH patients who presented for emergency department treatment at the hospital. Logistic regression models were used to explore the factors associated with violent and non-violent methods of DSH. RESULTS: Self-poisoning was the most common method of self-harm (80.3%). Prescription medication was the most common form of self-poison (57.6%), while a large number of patients used non-prescription paracetamol (40.9%). In the regression analysis, male gender, stating that the reason for DSH was to escape a situation and history of substance use were associated with violent method of DSH. CONCLUSION: Improved monitoring of prescription medications commonly used in DSH is integral to public health suicide prevention strategies in SA. This study underscores the need for substance use interventions in the healthcare setting.

19.
Blood ; 129(6): 771-782, 2017 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-27956387

RESUMO

Acute myeloid leukemia (AML) is an aggressive malignancy where despite improvements in conventional chemotherapy and bone marrow transplantation, overall survival remains poor. Sphingosine kinase 1 (SPHK1) generates the bioactive lipid sphingosine 1-phosphate (S1P) and has established roles in tumor initiation, progression, and chemotherapy resistance in a wide range of cancers. The role and targeting of SPHK1 in primary AML, however, has not been previously investigated. Here we show that SPHK1 is overexpressed and constitutively activated in primary AML patient blasts but not in normal mononuclear cells. Subsequent targeting of SPHK1 induced caspase-dependent cell death in AML cell lines, primary AML patient blasts, and isolated AML patient leukemic progenitor/stem cells, with negligible effects on normal bone marrow CD34+ progenitors from healthy donors. Furthermore, administration of SPHK1 inhibitors to orthotopic AML patient-derived xenografts reduced tumor burden and prolonged overall survival without affecting murine hematopoiesis. SPHK1 inhibition was associated with reduced survival signaling from S1P receptor 2, resulting in selective downregulation of the prosurvival protein MCL1. Subsequent analysis showed that the combination of BH3 mimetics with either SPHK1 inhibition or S1P receptor 2 antagonism triggered synergistic AML cell death. These results support the notion that SPHK1 is a bona fide therapeutic target for the treatment of AML.


Assuntos
Regulação Leucêmica da Expressão Gênica , Leucemia Mieloide Aguda/tratamento farmacológico , Proteína de Sequência 1 de Leucemia de Células Mieloides/antagonistas & inibidores , Fosfotransferases (Aceptor do Grupo Álcool)/antagonistas & inibidores , Receptores de Lisoesfingolipídeo/antagonistas & inibidores , Clorometilcetonas de Aminoácidos/farmacologia , Amino Álcoois/farmacologia , Animais , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Inibidores de Caspase/farmacologia , Caspases/genética , Caspases/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/patologia , Lisofosfolipídeos/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Terapia de Alvo Molecular , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Quinolinas/farmacologia , Receptores de Lisoesfingolipídeo/genética , Receptores de Lisoesfingolipídeo/metabolismo , Transdução de Sinais , Esfingosina/análogos & derivados , Esfingosina/metabolismo , Análise de Sobrevida , Ensaios Antitumorais Modelo de Xenoenxerto
20.
MMWR Morb Mortal Wkly Rep ; 68(38): 825-829, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31557146

RESUMO

Among the three wild poliovirus (WPV) types, type 2 (WPV2) was declared eradicated globally by the Global Commission for the Certification of Poliomyelitis Eradication (GCC) in 2015. Subsequently, in 2016, a global withdrawal of Sabin type 2 oral poliovirus vaccine (OPV2) from routine use, through a synchronized switch from the trivalent formulation of oral poliovirus vaccine (tOPV, containing vaccine virus types 1, 2, and 3) to the bivalent form (bOPV, containing types 1 and 3), was implemented. WPV type 3 (WPV3), last detected in 2012 (1), will possibly be declared eradicated in late 2019.* To ensure that polioviruses are not reintroduced to the human population after eradication, World Health Organization (WHO) Member States committed in 2015 to containing all polioviruses in poliovirus-essential facilities (PEFs) that are certified to meet stringent containment criteria; implementation of containment activities began that year for facilities retaining type 2 polioviruses (PV2), including type 2 oral poliovirus vaccine (OPV) materials (2). As of August 1, 2019, 26 countries have nominated 74 PEFs to retain PV2 materials. Twenty-five of these countries have established national authorities for containment (NACs), which are institutions nominated by ministries of health or equivalent bodies to be responsible for poliovirus containment certification. All designated PEFs are required to be enrolled in the certification process by December 31, 2019 (3). When GCC certifies WPV3 eradication, WPV3 and vaccine-derived poliovirus (VDPV) type 3 materials will also be required to be contained, leading to a temporary increase in the number of designated PEFs. When safer alternatives to wild and OPV/Sabin strains that do not require containment conditions are available for diagnostic and serologic testing, the number of PEFs will decrease. Facilities continuing to work with polioviruses after global eradication must minimize the risk for reintroduction into communities by adopting effective biorisk management practices.


Assuntos
Erradicação de Doenças , Saúde Global/estatística & dados numéricos , Poliomielite/prevenção & controle , Humanos , Poliomielite/epidemiologia
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