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1.
Arch Suicide Res ; 27(4): 1312-1338, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36237124

RESUMEN

OBJECTIVE: Some countries have implemented systems to monitor suicides in real-time. These systems differ because of the various ways in which suicides are identified and recorded. The main objective of this study was to conduct an international comparison of major real-time suicide mortality surveillance systems to identify joint strengths, challenges, and differences, and thereby inform best-practice criteria at local, national, and international levels. METHODS: Five major real-time suicide mortality surveillance systems of various coverage levels were identified and selected for review via an internet-based scoping exercise and prior knowledge of existing systems. Key information including the system components and practices was collated from those organizations that developed and operate each system using a structured template. The information was narratively and critically synthesized to determine similarities and differences between the systems. RESULTS: The comparative review of the five established real-time suicide surveillance systems revealed more commonalities than differences overall. Commonalities included rapid, routine surveillance based on minimal, provisional data to facilitate timely intervention and postvention efforts. Identified differences include the timeliness of case submission and system infrastructure. CONCLUSION: The recommended criteria could promote replicable components and practices in real-time suicide surveillance while offering flexibility in adapting to regional/local circumstances and resource availability.HIGHLIGHTSEvidence-informed recommendations for current best practice in real-time suicide surveillance.Proposed comprehensive framework can be adapted based on available resources and capacity.Real-time suicide mortality data facilitates rapid data-driven decision-making in suicide prevention.

3.
mBio ; 12(2)2021 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-33653882

RESUMEN

Functional characterization of bacterial proteins lags far behind the identification of new protein families. This is especially true for bacterial species that are more difficult to grow and genetically manipulate than model systems such as Escherichia coli and Bacillus subtilis To facilitate functional characterization of mycobacterial proteins, we have established a Mycobacterial Systems Resource (MSR) using the model organism Mycobacterium smegmatis This resource focuses specifically on 1,153 highly conserved core genes that are common to many mycobacterial species, including Mycobacterium tuberculosis, in order to provide the most relevant information and resources for the mycobacterial research community. The MSR includes both biological and bioinformatic resources. The biological resource includes (i) an expression plasmid library of 1,116 genes fused to a fluorescent protein for determining protein localization; (ii) a library of 569 precise deletions of nonessential genes; and (iii) a set of 843 CRISPR-interference (CRISPRi) plasmids specifically targeted to silence expression of essential core genes and genes for which a precise deletion was not obtained. The bioinformatic resource includes information about individual genes and a detailed assessment of protein localization. We anticipate that integration of these initial functional analyses and the availability of the biological resource will facilitate studies of these core proteins in many Mycobacterium species, including the less experimentally tractable pathogens M. abscessus, M. avium, M. kansasii, M. leprae, M. marinum, M. tuberculosis, and M. ulceransIMPORTANCE Diseases caused by mycobacterial species result in millions of deaths per year globally, and present a substantial health and economic burden, especially in immunocompromised patients. Difficulties inherent in working with mycobacterial pathogens have hampered the development and application of high-throughput genetics that can inform genome annotations and subsequent functional assays. To facilitate mycobacterial research, we have created a biological and bioinformatic resource (https://msrdb.org/) using Mycobacterium smegmatis as a model organism. The resource focuses specifically on 1,153 proteins that are highly conserved across the mycobacterial genus and, therefore, likely perform conserved mycobacterial core functions. Thus, functional insights from the MSR will apply to all mycobacterial species. We believe that the availability of this mycobacterial systems resource will accelerate research throughout the mycobacterial research community.


Asunto(s)
Genes Bacterianos , Mycobacterium smegmatis/genética , Mycobacterium/genética , Investigación , Biología Computacional , Biblioteca de Genes , Mycobacterium/clasificación , Mycobacterium/patogenicidad , Mycobacterium smegmatis/crecimiento & desarrollo
4.
EClinicalMedicine ; 18: 100246, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31956857

RESUMEN

BACKGROUND: Self-harm in adolescents is common and repetition frequent. Evidence for effective interventions to reduce self-harm is limited. Long term follow-up of existing studies is rare. METHODS: Extended follow up, from 18 to at least 36-months, of the SHIFT trial: a pragmatic, multi-centre, individually-randomised, controlled trial involving young people (11-17) who had self-harmed at least twice and presented to Child & Adolescent Mental Health Services (CAMHS). SHIFT evaluated manualised family therapy (FT) versus treatment as usual (TAU) in reducing repetition of self-harm leading to hospital attendance 18 months post-randomisation.We obtained ONS mortality data, adult mental health data, and further details of hospital attendance from routine Hospital Episode Statistics (HES) data plus researcher follow-up. We assessed longer-term differences in outcome using multivariable Cox Proportional Hazards regression analysis, and assessed all-cause mortality and morbidity relating to hospital attendances for reasons other than self-harm. STUDY REGISTRATION: ISRCTN 59793150. OUTCOMES: The original sample of 832 were randomised between April 2010 and December 2013. Extended follow-up continued until February 2017 for a median 55·4 months (range 0-82·5 months), providing post 18-month data for 804 (96·6%) participants, of whom 785 (94·4%) had a minimum of 36-months follow-up.There was no evidence of a between-group difference in the primary outcome during the extended follow-up period (Hazard Ratio (HR) 1·03; 95% CI: 0·83, 1·28; p-value=0·78), consistent with our findings in the original trial with 18 months follow-up (HR 1·14, 95% CI 0·87, 1·49; p-value 0·33). There was a reduced rate of self-harm in older participants aged 15-17 (HR 0·7, 95% CI 0·56, 0·88), as compared with those aged 11-14; and significantly increased rates of self-harm in participants whose index episode combined self-injury and poisoning (HR 1·8, 95% CI 1·2, 2·7). Two deaths were reported during the extended follow up period. INTERPRETATION: For adolescents referred to CAMHS after self-harm, having self-harmed at least once before, trial FT confers no benefits over TAU in reducing subsequent hospitalisation for self-harm over 18 months or 36 months. FUNDING: NIHR HTA Reference: 07/33/01.

5.
Proc Natl Acad Sci U S A ; 102(30): 10676-81, 2005 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-16030141

RESUMEN

The ESX-1 locus is a region critical for full virulence in Mycobacterium tuberculosis, which encodes two secreted proteins as well as other genes involved in their secretion. The mechanism of secretion of the two proteins, ESAT-6 and CFP-10, and their function remain unknown. Using proteomic methods to search for additional proteins secreted by the ESX-1 locus, we discovered that a protein encoded by a chromosomally unlinked gene, espA, is also secreted by strains that contain the ESX-1 locus but not by strains with ESX-1 deletions. Mutations in individual ESX-1 genes, including those that encode ESAT-6 and CFP-10, were found to block EspA secretion. Surprisingly, mutants that lack espA reciprocally failed to secrete ESAT-6 and CFP-10 and were as attenuated as ESX-1 mutants in virulence assays. The results indicate that secretion of these proteins, which are each critical for virulence of pathogenic mycobacteria, is mutually dependent. The results further suggest that discerning the nature of the interaction and the structure of macromolecular complexes will provide insights into both an alternative mechanism of protein secretion and mycobacterial virulence.


Asunto(s)
Antígenos Bacterianos/metabolismo , Proteínas Bacterianas/metabolismo , Complejos Multiproteicos/metabolismo , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/patogenicidad , Tuberculosis/inmunología , Animales , Antígenos Bacterianos/genética , Proteínas Bacterianas/genética , Secuencia de Bases , Western Blotting , Vectores Genéticos/genética , Espectrometría de Masas , Ratones , Ratones SCID , Datos de Secuencia Molecular , Complejos Multiproteicos/genética , Proteómica , Virulencia
6.
J Opt Soc Am A Opt Image Sci Vis ; 21(7): 1131-9, 2004 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15260244

RESUMEN

Contrast optimization, also known as image sharpening, is a method that can be used to estimate phase errors in coherent images. However, the contrast measure of a coherent image is a random variable because of the speckle present in coherent images. The variance of this measure puts a limit on the ability of contrast optimization to focus an image. We derive the probability distribution function of the most common contrast measure, the sum of the pixel intensities raised to a power. These statistics are then verified by a number of speckle simulations and compared with measured statistics from synthetic aperture sonar images. The developed statistics can be used as a tool to understand and improve the method of contrast optimization as well as assess its performance for a given imaging system. They can also be used to predict the effect of certain image processing operations on the contrast.

9.
J Immunol ; 155(7): 3329-37, 1995 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-7561026

RESUMEN

The regulation of B cell death plays roles in the selection of Ag-specific B cells in humoral immune responses, controlling B cell homeostasis and perhaps limiting transformation. The present work addresses whether CD95 induces tonsillar B cells to undergo apoptosis and, if so, whether contact-dependent CD40-L:CD40 signaling can rescue tonsillar B cells from CD95-induced apoptosis. CD95 triggering by anti-CD95 mAb (APO-1) was studied in human tonsillar B cell populations that were separated by density centrifugation into fractions enriched for either low density, CD38+ B cells or high density, resting B cells. Low density tonsillar B cells express CD95 and undergo anti-CD95-mediated apoptosis by analysis of cellular morphology or DNA fragmentation by TUNEL assay. The induction of apoptosis in low density tonsillar B cells by anti-CD95 mAb is inhibited by CD40 signals provided by stably transfected CD40-L+ 293 cells, but not by control transfected 293 cells (expressing CD8). In addition, the rescuing effect of CD40-L+ cells is inhibited specifically by anti-CD40-L (mAb 5c8). The counteracting effects of CD95 and CD40 signaling were also studied in Ramos 2G6, a homogeneous B cell tumor line of germinal center phenotype that expresses CD95 and CD40. Similar to the behavior of low density tonsillar B cells, Ramos 2G6 undergoes anti-CD95-mediated apoptosis, which is prevented by CD40-mediated rescue. These data show that CD95 induces apoptosis in low density tonsillar B cells and that CD40-L:CD40 interactions rescue low density tonsillar B cells or the B cell tumor Ramos 2G6 from CD95-induced apoptosis, and suggest roles for CD95 and CD40 in B cell death and selection, respectively.


Asunto(s)
Apoptosis/inmunología , Linfocitos B/inmunología , Antígenos CD40/inmunología , Tonsila Palatina/inmunología , Receptor fas/inmunología , Linfocitos B/patología , Secuencia de Bases , Células Cultivadas , ADN/análisis , Daño del ADN , Humanos , Datos de Secuencia Molecular
10.
J Leukoc Biol ; 58(2): 209-16, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7543921

RESUMEN

CD40 was originally described as a functionally significant B cell surface molecule. However, CD40 is also expressed on monocytes, dendritic cells, epithelial cells, and basophils. We now report that synovial membrane (SM) or dermal fibroblasts also express cell surface CD40 in vitro. Fibroblast CD40 expression declines with increasing time in culture and recombinant interferon-gamma (rINF-gamma) induces fibroblast CD40 up-regulation. This effect of rINF-gamma is augmented by recombinant interleukin-1 alpha or recombinant tumor necrosis factor-alpha. CD40 expression on fibroblasts is functionally significant because CD40L-CD40 interactions induce SM fibroblast CD54 (intercellular adhesion molecule-1) and CD106 (vascular cell adhesion molecule-1) up-regulation. Moreover, ligation of CD40 augments IL-6 production by SM fibroblasts and induces fibroblasts to proliferate. In addition, rINF-gamma enhances the effect of CD40L-CD40 interactions on fibroblast proliferation. Taken together, these studies show that fibroblasts can express CD40, cytokines can regulate fibroblast CD40 expression, and CD40 ligation induces fibroblast activation and proliferation.


Asunto(s)
Antígenos CD/biosíntesis , Antígenos de Diferenciación de Linfocitos B/biosíntesis , Moléculas de Adhesión Celular/biosíntesis , Citocinas/farmacología , Molécula 1 de Adhesión Intercelular/biosíntesis , Interleucina-6/biosíntesis , Piel/inmunología , Membrana Sinovial/inmunología , Animales , Anticuerpos Monoclonales/farmacología , Antígenos CD/inmunología , Antígenos de Diferenciación de Linfocitos B/inmunología , Artritis Reumatoide/inmunología , Antígenos CD40 , División Celular , Células Cultivadas , Fibroblastos/efectos de los fármacos , Fibroblastos/inmunología , Fibroblastos/patología , Regulación de la Expresión Génica , Humanos , Interferón gamma/farmacología , Interleucina-1/farmacología , Interleucina-4/farmacología , Ratones/inmunología , Osteoartritis/inmunología , Proteínas Recombinantes/farmacología , Piel/efectos de los fármacos , Membrana Sinovial/efectos de los fármacos , Factor de Necrosis Tumoral alfa/farmacología , Molécula 1 de Adhesión Celular Vascular
11.
Laryngoscope ; 104(4): 420-5, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8164480

RESUMEN

Investigation of the effects of various factors on nerve regeneration has been compromised by the lack of an accurate and objective technique which can monitor dynamic changes in the status of nerve-muscle innervation over the entire course of regeneration. The approach of evoked electromyography (EEMG) was adopted to obtain temporal and quantitative data during nerve regeneration. Initially, transcutaneous nerve stimulation and percutaneous muscle recording was performed, but the approach was abandoned because of the high interest variability (20% average deviation) and requirement for anesthesia during testing. A new approach using chronically implanted stimulation and recording electrodes was adopted in an attempt to circumvent these problems. Initial acute studies performed in the hindlimb of the anesthetized rat identified stable EEMG recording sites with sciatic nerve stimulation. In a second study conducted in chronically implanted unanesthetized unrestrained animals, EEMG recording from these sites demonstrated remarkable stability with an average interest variability of only 5%. Preliminary results have been obtained with this technique in monitoring the progression of hindlimb reinnervation following crush and transection nerve injuries.


Asunto(s)
Electrodos Implantados , Electromiografía , Nervio Ciático/fisiopatología , Animales , Potenciales Evocados/fisiología , Miembro Posterior/inervación , Modelos Biológicos , Regeneración Nerviosa/fisiología , Unión Neuromuscular/fisiopatología , Ratas , Nervio Ciático/lesiones , Factores de Tiempo , Estimulación Eléctrica Transcutánea del Nervio
13.
J Med Microbiol ; 35(1): 49-52, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1906545

RESUMEN

Possible Haemophilus influenzae colonies in cultures of sputum samples are currently identified by tests for dependence on X and V factors. This method requires further overnight culture and may give a relatively high number of false negative results. Identification of suspected H. influenzae colonies by a 5-min test for production of indole and beta-galactosidase followed by a 1-h porphyrin test was compared with tests for dependence on X and V factors. A commercially produced form of the rapid tests (Haemstrip, Lab M, Bury, Lancs) was used to test 252 potential haemophilus colonies from cultures of sputum samples on heated blood agar. Colonies that were beta-galactosidase-positive after 5 min were considered to be non-H. influenzae and those that were beta-galactosidase-negative but indole-positive were considered to be H. influenzae. At this stage the test had a sensitivity of 99.4% and a specificity of 90.9%. After 1 h, only colonies that were beta-galactosidase- and porphyrin-negative were considered to be H. influenzae, the sensitivity was then 99.5% and the specificity 100%. Similar results were found with colonies from sputum cultures on selective heated blood agar containing bacitracin. The X and V dependence and Haemstrip results were in 97.6% agreement in a double blind test. Of 100 non-haemophilus colonies tested by Haemstrip, two pseudomonads could have been identified as H. influenzae by this method. The high positive predictive value of Haemstrip results depends partly on the initial recognition of potential haemophilus colonies.


Asunto(s)
Técnicas Bacteriológicas , Haemophilus influenzae/aislamiento & purificación , Esputo/microbiología , beta-Galactosidasa/análisis , Haemophilus influenzae/enzimología , Haemophilus influenzae/crecimiento & desarrollo , Porfirinas/análisis
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