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Objetivo: Revisar los estudios sobre violencia en el noviazgo (VN) de jóvenes, desarrollados en Colombia y América Latina (2016-2020), para dar cuenta de sus características metodológicas y principales hallazgos. Metodología: La búsqueda de artículos sobre VN se realizó en siete bases de datos y aquellos debían cumplir los siguientes criterios de inclusión: 1) muestra de jóvenes, 2) estudio realizado en Colombia o en otro país latinoamericano, y 3) publicados entre 2016 y 2020. Se clasifican los estudios teniendo en cuenta su metodología. Resultados: Se incluyeron 38 artículos, de los cuales 23 cumplieron con los criterios de análisis: 13 de Colombia, 4 de México, 4 de Brasil, 2 de Chile y 1 en Argentina. Solo 3 de 23 artículos utilizaron metodología mixta, dos en Brasil y uno en Colombia; el resto utilizó metodología cuantitativa. Se describe cómo se ha conceptualizado la VN y se clasifican los estudios en hallazgos epidemiológicos, estudios instrumentales y estudios sobre las creencias de los/as jóvenes sobre VN, clasificación dada por el objetivo de la investigación. Conclusiones: Conocer cómo se conceptualiza la VN y las prevalencias de la VN en jóvenes para entenderla en el contexto Latinoamericano resulta fundamental para prevenir este problema. Los hallazgos presentados en este artículo pueden servir de insumo para las instituciones y organizaciones sociales, para comprender la violencia en el noviazgo y generar herramientas para su prevención.
Objective: To review the studies on dating violence (dv) of young people, developed in Colombia and Latin America (2016-2020), to account for their methodological characteristics and main findings. Methodology: The search for articles on vn was carried out in seven databases and those had to meet the following inclusion criteria: 1) sample of young people, 2) study carried out in Colombia or in another Latin American country, and 3) published between 2016 and 2020. Studies are classified taking into account their methodology. Results: 38 articles were included, of which 23 met the analysis criteria: 13 from Colombia, 4 from Mexico, 4 from Brazil, 2 from Chile, and 1 from Argentina. Only 3 of 23 articles used mixed methodology, two in Brazil and one in Colombia; the rest used quantitative methodology. It describes how vn has been conceptualized and studies are classified into epidemiological findings, instrumental studies, and studies on young people's beliefs about vn, classification given by the objective of the research. Conclusions: Knowing how vn is conceptualized and the prevalence of vn in young people to understand it in the Latin American context is essential to prevent this problem. The findings presented in this article can serve as an input for social institutions and organizations to understand dating violence and generate tools for its prevention.
Objetivo: Revisar os estudos sobre violência no namoro (dv) de jovens, desenvolvidos na Colômbia e na América Latina (2016-2020), para dar conta de suas características metodológicas e principais achados. Metodologia: A busca de artigos sobre vn foi realizada em sete bases de dados e os mesmos deveriam atender aos seguintes critérios de inclusão: 1) amostra de jovens, 2) estudo realizado na Colômbia ou em outro país latino-americano e 3) publicado entre 2016 e 2020. Os estudos são classificados de acordo com sua metodologia. Resultados: foram incluídos 38 artigos, dos quais 23 atenderam aos critérios de análise: 13 da Colômbia, 4 do México, 4 do Brasil, 2 do Chile e 1 da Argentina. Apenas 3 dos 23 artigos utilizaram metodologia mista, dois no Brasil e um na Colômbia; o restante utilizou metodologia quantitativa. Descreve como o vn foi conceituado e os estudos são classificados em achados epidemiológicos, estudos instrumentais e estudos sobre as crenças dos jovens sobre o vn, classificação dada pelo objetivo da pesquisa. Conclusões: Saber como vn é conceituado e a prevalência de vn em jovens para entendê-lo no contexto latino-americano é essencial para prevenir esse problema. Os achados apresentados neste artigo podem servir de subsídio para que instituições e organizações sociais compreendam a violência no namoro e gerem ferramentas para sua prevenção.Palavras-chave: América Latina, Colômbia, violência de gênero, violência por parceiro íntimo, violência no namoro.
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For young women, the power imbalance in favor of males in dating relationships has been related to dating violence (DV) victimization. In addition, the use of rumination to cope with DV may increase their psychological distress. The purpose of the current study was to examine whether experiences of DV and rumination mediate the association between power imbalance and suicide risk (SR). The sample comprised 1,216 young women aged between 18 and 28 years from Colombia (n = 461) and Spain (n = 755), in a heterosexual dating relationship, not married or cohabiting with a partner and without children. The following scales were applied: The Sexual Relationship Power Scale-Modified, The Dating Violence Questionnaire--R (DVQ-R); Cyberdating Abuse Questionnaire, Measure of Affect Regulation Scale (MARS), and The Spanish Suicide Risk Scale. A sequential mediation paths model was tested. Results indicated that power imbalance was associated with DV victimization. Furthermore, DV was associated with more rumination, which was also linked to a greater SR in both countries. Rumination may be a mechanism through which experiences of DV victimization negatively influence mental health in young women and is an important variable related cross-culturally to SR. The findings suggest an equality approach, addressing the power imbalance in dating relationships, empowering girls to prevent DV, and teaching coping strategies for dealing with victimization and its consequences.
Assuntos
Vítimas de Crime , Violência por Parceiro Íntimo , Suicídio , Masculino , Humanos , Feminino , Criança , Adolescente , Adulto Jovem , Adulto , Colômbia , Comparação Transcultural , Violência/psicologia , Violência por Parceiro Íntimo/psicologia , Vítimas de Crime/psicologiaRESUMO
For decades, in a situation of armed conflict in Colombia, women have suffered polyvictimization and discrimination with severe consequences that last even during the post-war peace process. This study analyzes the impact on posttraumatic stress and recovery of war-related violence against women, discrimination, and social acknowledgment. A cross-sectional study was conducted in 2019-2020. Participants were 148 women with a mean age of 47.66years (range 18-83), contacted through the NGO Ruta Pacifica de las Mujeres who had experienced significant personal violence. Results show that levels of perceived discrimination and lack of social acknowledgment are mediators in the relationship between polyvictimization and posttraumatic stress symptoms. Recognition by significant others, disapproval by family and the larger social milieu affects different posttraumatic stress disorder (PTSD) dimensions and therefore how these women adapt to the effects of trauma. Findings provide strong evidence that the way society and family treats women after a traumatic event affects how the victim recovers from this event. Recognition as a victim and disapproval can coexist and be a burden for women if not adequately addressed. Results stress the importance of understanding and intervening in PTSD recovery through the analysis of social processes, and not only through and individual focus.
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Stump appendicitis is a rare complication of appendectomy. It may develop from a few weeks to several years after the surgical procedure. To achieve its diagnosis a high index of suspicion is necessary. The objective of this publication is to make a review of two cases of this entity that occurred in our institution and to mention its most frequent imaging findings. Computed tomography is an excellent method to assess this entity, not only for its diagnosis but also to rule out other pathologies that present similar clinical features.
La apendicitis del muñón es una complicación poco frecuente de la apendicectomía. Puede aparecer desde unas semanas a varios años luego del procedimiento quirúrgico. Para arribar a su diagnóstico es necesario un alto índice de sospecha. El objetivo de esta publicación es hacer una reseña de dos casos de esta entidad ocurridos en nuestra institución y mencionar sus hallazgos imagenológicos más frecuentes. La tomografía computarizada es un excelente método para valorar esta entidad, no solo para su diagnóstico sino también para descartar otras patologías que presentan un cuadro clínico similar.
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Apendicite , Apendicectomia , Apendicite/diagnóstico por imagem , Apendicite/etiologia , Apendicite/cirurgia , Diagnóstico Diferencial , Humanos , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/etiologia , Tomografia Computadorizada por Raios XRESUMO
Resumen La apendicitis del muñón es una complicación poco frecuente de la apendicectomía. Puede aparecer desde unas semanas a varios años luego del procedimiento quirúrgico. Para arribar a su diagnóstico es necesario un alto índice de sospecha. El objetivo de esta publicación es hacer una reseña de dos casos de esta entidad ocurridos en nuestra institución y mencionar sus hallazgos imagenológicos más frecuentes. La tomografía computarizada es un excelente método para valorar esta entidad, no solo para su diagnóstico sino también para descartar otras patologías que presentan un cuadro clínico similar.
Abstract Stump appendicitis is a rare complication of appendectomy. It may develop from a few weeks to several years after the surgical procedure. To achieve its diagnosis a high index of suspicion is necessary. The objective of this publication is to make a re view of two cases of this entity that occurred in our institution and to mention its most frequent imaging findings. Computed tomography is an excellent method to assess this entity, not only for its diagnosis but also to rule out other pathologies that present similar clinical features.
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Humanos , Apendicite/cirurgia , Apendicite/etiologia , Apendicite/diagnóstico por imagem , Apendicectomia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Diagnóstico DiferencialRESUMO
Adipose tissue can affect the metabolic control of the cardiovascular system, and its anatomic location can affect the vascular function differently. In this study, biochemical and phenotypical characteristics of adipose tissue from periaortic fat were evaluated. Periaortic and subcutaneous adipose tissues were obtained from areas surrounding the ascending aorta and sternotomy incision, respectively. Adipose tissues were collected from patients undergoing myocardial revascularization or mitral valve replacement surgery. Morphological studies with hematoxylin/eosin and immunohistochemical assay were performed in situ to quantify adipokine expression. To analyze adipogenic capacity, adipokine expression, and the levels of thermogenic proteins, adipocyte precursor cells were isolated from periaortic and subcutaneous adipose tissues and induced to differentiation. The precursors of adipocytes from the periaortic tissue accumulated less triglycerides than those from the subcutaneous tissue after differentiation and were smaller than those from subcutaneous adipose tissue. The levels of proteins involved in thermogenesis and energy expenditure increased significantly in periaortic adipose tissue. Additionally, the expression levels of adipokines that affect carbohydrate metabolism, such as FGF21, increased significantly in mature adipocytes induced from periaortic adipose tissue. These results demonstrate that precursors of periaortic adipose tissue in humans may affect cardiovascular events and might serve as a target for preventing vascular diseases.
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It is now well established that in yeast, and likely most eukaryotic organisms, initial DNA replication of the leading strand is by DNA polymerase ε and of the lagging strand by DNA polymerase δ. However, the role of Pol δ in replication of the leading strand is uncertain. In this work, we use a reporter system in Saccharomyces cerevisiae to measure mutation rates at specific base pairs in order to determine the effect of heterozygous or homozygous proofreading-defective mutants of either Pol ε or Pol δ in diploid strains. We find that wild-type Pol ε molecules cannot proofread errors created by proofreading-defective Pol ε molecules, whereas Pol δ can not only proofread errors created by proofreading-defective Pol δ molecules, but can also proofread errors created by Pol ε-defective molecules. These results suggest that any interruption in DNA synthesis on the leading strand is likely to result in completion by Pol δ and also explain the higher mutation rates observed in Pol δ-proofreading mutants compared to Pol ε-proofreading defective mutants. For strains reverting via ATâGC, TAâGC, CGâAT, and GCâAT mutations, we find in addition a strong effect of gene orientation on mutation rate in proofreading-defective strains and demonstrate that much of this orientation dependence is due to differential efficiencies of mispair elongation. We also find that a 3'-terminal 8 oxoG, unlike a 3'-terminal G, is efficiently extended opposite an A and is not subject to proofreading. Proofreading mutations have been shown to result in tumor formation in both mice and humans; the results presented here can help explain the properties exhibited by those proofreading mutants.
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DNA Polimerase III/metabolismo , DNA Polimerase II/metabolismo , Replicação do DNA , Saccharomyces cerevisiae/enzimologia , Animais , Reparo de Erro de Pareamento de DNA , DNA Fúngico/genética , DNA Fúngico/metabolismo , Escherichia coli/metabolismo , Humanos , Camundongos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismoRESUMO
Estado, mercado y disciplinamiento configuran el triple dispositivo a través del cual el occidente ha buscado conjurar la violencia con la esperanza de encuadrarla y eliminarla. A pesar o tal vez merced a los controles que se le quisieron imponer, la violencia está lejos de ser domesticada y en la modernidad ha adoptado formas más refinadas y novedosas. El monopolio estatal de la violencia ha tenido como contraparte la guerra civil y como forma paroxística el totalitarismo. La explotación ha sido la contracara de la "humanitaria" división capitalista del trabajo. El sujeto criminal y el terrorista fueron producto de una subjetivación que aspira a ubicar en la periferia social una violencia que en realidad le es inherente. Un sino trágico atraviesa al triple afán de control: a cada violencia que se pretende exorcizar sobreviene otra que no es más que el retorno de aquella forcluida. Así, la eliminación definitiva de la violencia deviene una posibilidad imposible que, no obstante su consabido fracaso, continúa como horizonte utópico de nuestras sociedades
Estado, mercado e disciplinamento configuram o tríplice dispositivo através do qual Ocidente tem procurado conjurar a violência com a esperança de enquadrá-la e eliminá-la. A pesar, ou talvez por causa dos controles que quiseram impor-lhe, a violência está longe de ser domesticada e, na modernidade, tem adotado formas mais refinadas e novas. O monopólio estatal da violência teve como contraparte a guerra civil e, como forma paroxística, o totalitarismo. A exploração tem sido a contra cara da "humanitária" divisão capitalista do trabalho. O sujeito criminal e o terrorista foram produto de una subjetivação que aspira a pôr na periferia social uma violência que na verdade é inerente a ela. Uma sina trágica atravessa a tríplice vontade de controle: a cada violência que se pretende exorcizar sobrevém outra, que não é outra coisa senão o retorno daquela forcluída. Assim, a eliminação definitiva da violência se torna una possibilidade impossível que, no entanto seu conhecido fracasso, continua como horizonte utópico de nossas sociedades
State, market, and disciplining configure a triple device through which the West has sought to avert violence hoping to frame it and eliminate it. Despite or perhaps thanks to the controls that were wanted to impose, violence is far from being domesticated and modernity has adopted more refined and innovative ways to express it. State monopoly on violence has had the civil war as counterpart and totalitarianism as a paroxysmal form. Exploitation has been the other side of the "humanitarian" capitalist division of labour. Criminal and terrorist subjects are product of a subjectivation that aspires to be located on the periphery of social violence but it is actually inherent. A tragic fate transpasses the triple control effort: every violence intended to be exorcised ensues its return. Thus, the ultimate violence elimination becomes an impossibility that, despite its well-known failure, it continues as an utopian horizon of our societies
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Humanos , Política , Violência , EstadoRESUMO
8-oxoG is one of the most common and mutagenic DNA base lesions caused by oxidative damage. However, it has not been possible to study the replication of a known 8-oxoG base in vivo in order to determine the accuracy of its replication, the influence of various components on that accuracy, and the extent to which an 8-oxoG might present a barrier to replication. We have been able to place a single 8-oxoG into the Saccharomyces cerevisiae chromosome in a defined location using single-strand oligonucleotide transformation and to study its replication in a fully normal chromosome context. During replication, 8-oxoG is recognized as a lesion and triggers a switch to translesion synthesis by Pol η, which replicates 8-oxoG with an accuracy (insertion of a C opposite the 8-oxoG) of approximately 94%. In the absence of Pol η, template switching to the newly synthesized sister chromatid is observed at least one third of the time; replication of the 8-oxoG in the absence of Pol η is less than 40% accurate. The mismatch repair (MMR) system plays an important role in 8-oxoG replication. Template switching is blocked by MMR and replication accuracy even in the absence of Pol η is approximately 95% when MMR is active. These findings indicate that in light of the overlapping mechanisms by which errors in 8-oxoG replication can be avoided in the cell, the mutagenic threat of 8-oxoG is due more to its abundance than the effect of a single lesion. In addition, the methods used here should be applicable to the study of any lesion that can be stably incorporated into synthetic oligonucleotides.
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DNA Polimerase Dirigida por DNA/genética , Desoxiguanosina/análogos & derivados , Mutagênese , Estresse Oxidativo/genética , Saccharomyces cerevisiae/genética , 8-Hidroxi-2'-Desoxiguanosina , Dano ao DNA/genética , Reparo do DNA/genética , Replicação do DNA/genética , DNA Polimerase Dirigida por DNA/metabolismo , Desoxiguanosina/genética , Guanina/metabolismoRESUMO
Oxidative damage to DNA constitutes a major threat to the faithful replication of DNA in all organisms and it is therefore important to understand the various mechanisms that are responsible for repair of such damage and the consequences of unrepaired damage. In these experiments, we make use of a reporter system in Saccharomyces cerevisiae that can measure the specific increase of each type of base pair mutation by measuring reversion to a Trp+ phenotype. We demonstrate that increased oxidative damage due to the absence of the superoxide dismutase gene, SOD1, increases all types of base pair mutations and that mismatch repair (MMR) reduces some, but not all, types of mutations. By analyzing various strains that can revert only via a specific CGâAT transversion in backgrounds deficient in Ogg1 (encoding an 8-oxoG glycosylase), we can study mutagenesis due to a known 8-oxoG base. We show as expected that MMR helps prevent mutagenesis due to this damaged base and that Pol η is important for its accurate replication. In addition we find that its accurate replication is facilitated by template switching, as loss of either RAD5 or MMS2 leads to a significant decrease in accurate replication. We observe that these ogg1 strains accumulate revertants during prolonged incubation on plates, in a process most likely due to retromutagenesis.
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DNA Glicosilases/genética , Replicação do DNA/genética , Guanina/análogos & derivados , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Superóxido Dismutase/genética , Dano ao DNA/genética , DNA Helicases/genética , Reparo de Erro de Pareamento de DNA/genética , Reparo do DNA/genética , Guanina/metabolismo , Mutagênese/genética , Mutação , Estresse Oxidativo , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1 , Ubiquitina-Proteína Ligases/genéticaRESUMO
Agricultural and industrial practices more than doubled the intrinsic rate of terrestrial N fixation over the past century with drastic consequences, including increased atmospheric nitrous oxide (N(2)O) concentrations. N(2)O is a potent greenhouse gas and contributor to ozone layer destruction, and its release from fixed N is almost entirely controlled by microbial activities. Mitigation of N(2)O emissions to the atmosphere has been attributed exclusively to denitrifiers possessing NosZ, the enzyme system catalyzing N(2)O to N(2) reduction. We demonstrate that diverse microbial taxa possess divergent nos clusters with genes that are related yet evolutionarily distinct from the typical nos genes of denitirifers. nos clusters with atypical nosZ occur in Bacteria and Archaea that denitrify (44% of genomes), do not possess other denitrification genes (56%), or perform dissimilatory nitrate reduction to ammonium (DNRA; (31%). Experiments with the DNRA soil bacterium Anaeromyxobacter dehalogenans demonstrated that the atypical NosZ is an effective N(2)O reductase, and PCR-based surveys suggested that atypical nosZ are abundant in terrestrial environments. Bioinformatic analyses revealed that atypical nos clusters possess distinctive regulatory and functional components (e.g., Sec vs. Tat secretion pathway in typical nos), and that previous nosZ-targeted PCR primers do not capture the atypical nosZ diversity. Collectively, our results suggest that nondenitrifying populations with a broad range of metabolisms and habitats are potentially significant contributors to N(2)O consumption. Apparently, a large, previously unrecognized group of environmental nosZ has not been accounted for, and characterizing their contributions to N(2)O consumption will advance understanding of the ecological controls on N(2)O emissions and lead to refined greenhouse gas flux models.
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Bactérias/classificação , Variação Genética , Nitrificação , Oxirredutases/genética , Microbiologia do Solo , Bactérias/enzimologia , Bactérias/genética , Sequência de Bases , Primers do DNA , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da PolimeraseRESUMO
We have studied single-strand oligonucleotide (oligo) transformation of yeast by using 40-nt long oligos that create multiple base changes to the yeast genome spread throughout the length of the oligos, making it possible to measure the portions of an oligo that are incorporated during transformation. Although the transformation process is greatly inhibited by DNA mismatch repair (MMR), the pattern of incorporation is essentially the same in the presence or absence of MMR, whether the oligo anneals to the leading or lagging strand of DNA replication, or whether phosphorothioate linkages are used at either end. A central core of approximately 15 nt is incorporated with a frequency of >90%; the ends are incorporated with a lower frequency, and loss of the two ends appears to be by different mechanisms. Bases that are 5-10 nt from the 5' end are generally lost with a frequency of >95%, likely through a process involving flap excision. On the 3' end, bases 5-10 nt from the 3' end are lost about 1/3 of the time. These results indicate that oligos can be used to create multiple simultaneous changes to the yeast genome, even in the presence of MMR.
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Genoma Fúngico , Oligonucleotídeos/genética , Transformação Genética , Leveduras/genética , Pareamento Incorreto de Bases , Reparo do DNA , Reação em Cadeia da PolimeraseRESUMO
Mismatch repair (MMR) is a major DNA repair pathway in cells from all branches of life that removes replication errors in a strand-specific manner, such that mismatched nucleotides are preferentially removed from the newly replicated strand of DNA. Here we demonstrate a role for MMR in helping create new phenotypes in nondividing cells. We show that mispairs in yeast that escape MMR during replication can later be subject to MMR activity in a replication strand-independent manner in nondividing cells, resulting in either fully wild-type or mutant DNA sequence. In one case, this activity is responsible for what appears to be adaptive mutation. This replication strand-independent MMR activity could contribute to the formation of tumors arising in nondividing cells and could also contribute to mutagenesis observed during somatic hypermutation of Ig genes.
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Reparo de Erro de Pareamento de DNA/genética , Mutação , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Sequência de Bases , Dano ao DNA , Replicação do DNA/genética , DNA Fúngico/genética , DNA Fúngico/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Genótipo , Modelos Genéticos , Mutagênese , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Triptofano Sintase/genética , Triptofano Sintase/metabolismoRESUMO
PURPOSE: To estimate the occurrence and correlates of anorexia nervosa and bulimia nervosa-related symptoms in a Latina sample of U.S. adolescents. METHOD: Approximately 1866 Latinas ranging in age from 11-20 years old are included in this study. These adolescents are a sub-sample from the National Longitudinal Survey on Adolescent Health. Along with self-reports of eating disorder-related variables, we measured related biological, contextual, behavioral, and psychosocial correlates, including use of various substances. CONCLUSION: Chi-square analysis showed the prevalence in all Latina sub-groups was relatively consistent with the U.S. trends. Latinas of higher socioeconomic status were more at risk for eating disorders. Body dissatisfaction, negative affectivity, substance use, and low self-esteem were all positively correlated with eating disorder symptoms. These results suggest screening and treatment services are needed across groups of Latina adolescents.
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Anorexia Nervosa/etnologia , Anorexia Nervosa/epidemiologia , Bulimia/etnologia , Bulimia/epidemiologia , Hispânico ou Latino/psicologia , Transtornos Relacionados ao Uso de Substâncias/complicações , Adolescente , Adulto , Criança , Feminino , Inquéritos Epidemiológicos , Humanos , Estudos Longitudinais , Estados Unidos/epidemiologiaRESUMO
OBJECTIVES: To compare the performance of two rapid systems for the diagnosis of cholera with the culture method, and to propose a strategy for improving the specificity and sensitivity of these systems and reducing the costs involved in making a diagnosis. METHODS: The following institutions participated in the study: the National Bacteriology Referral Center (Centro Nacional de Referencia en Bacteriologia, CNRB) of the Costa Rican Institute for Research and Teaching in Nutrition and Health (Instituto Costarricense de Investigacion y Ensenanza en Nutricion y Salud, INCIENSA) and various hospitals in the provinces of Alajuela, Guanacaste and San Jose, in Costa Rica. A total of 237 feces samples were used to asses the performance of two tests for the rapid detection of Vibrio cholerae 01: the Pathogen Detection Kit (PDK, Intelligent Monitoring Systems, Gainesville, Florida, USA) and Cholera-SMART (New Horizons Diagnostics Corp., Columbia, Maryland, USA), both when applied directly (direct SMART and direct PDK) and when applied to specimens cultured in broth-enriched medium for 6 hours (SMART-6 and CPK-6) and for 18 hours (SMART-18 and PDK-18) at 37 degrees C in alkaline peptone water. Liquid and partially formed stools were cultured and examined by means of the rapid direct test; when the initial result was negative, the tests were repeated after culture for periods of 6 and 18 hours. Rectal and fecal swabs were obtained from feces cultured in enriched-broth medium for 6 and 18 hours. In addition, we studied the sensitivity of the rapid testing systems by using pure cultures of V. cholerae 01 (strain SOS-833, CNRB, Costa Rica) that were incubated for 18 to 24 hours, and we assessed the usefulness of observing motility under the microscope in order to rationalize the use of rapid methods. RESULTS: The sensitivity of the direct SMART test and of the direct PDK test was 100% when samples obtained from liquid and partially formed stools and from the intestinal contents of dead bodies were used. With these samples, the direct SMART procedure showed a specificity of 100%, whereas the direct PDK procedure showed a specificity that ranged from 85.7% to 77.4%, depending on the type of sample. False positives obtained with the direct PDK method turned out to be negative with PDK-6 and PDK-18. Among the rectal and fecal swabs of persons with and without diarrhea or who had received prior treatment with antibiotics, three results that were negative with the SMART-6 procedure and two that were negative with the PDK-6 procedure turned out to be positive with the SMART-18 and PDK-18 procedures, respectively. Both systems showed excellent concordance (kappa index above 0.9) throughout. Both systems were sensitive to 6 x 10(7) colony-forming units per milliliter (cfu/mL), which was concordant with the microscopic observation of 10 microorganisms or more per field with the type of motility that characterizes vibrios (at 1000 x magnification). Samples having fewer than 10 microorganisms with the motility that characterizes vibrios had concentrations between 6 x 10(3) and 6 x 10(6) cfu/mL and became positive only after incubation in enriched-broth medium for 6 to 18 hours. We propose a strategy for diagnosing the presence of V. cholerae 01 infection in less time than it takes with traditional methods, with positive and negative predictive values of 100%. CONCLUSIONS: The SMART and PDK systems make it possible to accurately diagnose cholera quickly, don't require sophisticated equipment or highly qualified technical personnel, and perform satisfactorily in field conditions. Through the proposed strategy, it becomes possible to improve the specificity and sensitivity of these systems and to reduce the cost of making a diagnosis, thus making them suitable for use in cholera surveillance in low-income settings where this disease is a serious public health problem.
Assuntos
Cólera/diagnóstico , Fezes/microbiologia , Vibrio cholerae/isolamento & purificação , Testes de Aglutinação/estatística & dados numéricos , Costa Rica , Humanos , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Vibrio cholerae/imunologiaRESUMO
OBJETIVOS: Comparar el desempeño de dos sistemas rápidos de diagnóstico de cólera con el método de cultivo y proponer una estrategia que permita mejorar la especificidad y la sensibilidad de estos sistemas y disminuir los costos del diagnóstico. MÉTODOS: En el estudio participaron el Centro Nacional de Referencia en Bacteriología (CNRB) del Instituto Costarricense de Investigación y Enseñanza en Nutrición y Salud (INCIENSA) y hospitales de las provincias de Alajuela, Guanacaste y San José, en Costa Rica. Se emplearon 237 muestras de heces para evaluar el desempeño de dos pruebas rápidas para el diagnóstico de Vibrio cholerae O1: Pathogen Detection Kit® (PDK, Intelligent Monitoring Systems, Gainsville, Florida, EUA) y Cholera-SMART® (New Horizons Diagnostics Corp., Columbia, Maryland, EUA), tanto en forma directa (SMART directo y PDK directo) como a partir de cultivos de enriquecimiento de 6 horas (SMART-6 y PDK-6) y de 18 horas (SMART-18 y PDK-18) a 37 ºC en agua de peptona alcalina. Las muestras diarreicas y semiformadas se cultivaron y se evaluaron con las pruebas rápidas directas; cuando el resultado inicial era negativo se repitieron a las 6 y 18 horas de cultivo. Los hisopados rectales y fecales se evaluaron a partir de cultivos de enriquecimiento de 6 y de 18 horas. Adicionalmente se estudió la sensibilidad analítica de los sistemas rápidos con cultivos puros de 18 a 24 horas de incubación de V. cholerae O1 (cepa SOS-833, CNRB, Costa Rica) y se evaluó la utilidad del análisis microscópico de la motilidad para racionalizar el uso de las técnicas rápidas. RESULTADOS: La sensibilidad, tanto de SMART directo como de PDK directo, fue de 100 por ciento en muestras de heces diarreicas y semiformadas y en contenido intestinal de cadáveres. Con estas muestras, el procedimiento SMART directo mostró una especificidad de 100 por ciento, mientras que con el PDK directo esta fue de 85,7 por ciento a 77,4 por ciento, en dependencia del tipo de muestra. Los resultados positivos falsos obtenidos mediante PDK directo resultaron negativos con PDK-6 y PDK-18. Entre los hisopados rectales y fecales de personas con y sin diarrea o que recibieron tratamiento previo con antibióticos se observaron tres resultados negativos falsos...