6 research outputs found

    La susceptibilidad de los pacientes diabéticos frente a la tuberculosis, un enfoque desde la perspectiva inmunológica

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    Introduction: The interaction between diabetes and tuberculosis represents a topic of growing medical and public health interest. Both conditions, persistent and significant globally, impact millions of individuals. Diabetes mellitus, characterized by chronic hyperglycemia due to insufficient insulin production or resistance to this hormone, has seen an increase in prevalence. On the other hand, tuberculosis, caused by Mycobacterium tuberculosis (Mtb), remains one of the leading infectious causes of morbidity and mortality worldwide. Objective: To highlight the susceptibility of diabetic patients to tuberculosis from an immunological perspective. Methodology: The approach included a comprehensive literature review using high-impact databases such as PubMed, Google Scholar, and other relevant sources in the field. Results: Diabetic patients exhibit an altered immune response characterized by compromised macrophage and T-cell function, and a reduction in the production of antimicrobial peptides. These factors contribute to a higher bacterial load and a favorable environment for the proliferation of Mycobacterium tuberculosis. Conclusions: Diabetes mellitus intensifies susceptibility to tuberculosis through multiple immunological dysfunctions. It is essential to integrate glycemic management and immunological surveillance in the treatment of diabetic patients with tuberculosis to improve clinical outcomes and reduce the incidence of the disease.  Introducción: la interacción entre la diabetes y la tuberculosis representa un tema de creciente interés médico y de salud pública. Ambas condiciones, persistentes y significativas a nivel global, impactan a millones de individuos. La diabetes mellitus, caracterizada por la hiperglucemia crónica debido a la insuficiente producción de insulina o a la resistencia a esta hormona, ha experimentado un aumento en su prevalencia. Por otro lado, la tuberculosis, causada por Mycobacterium tuberculosis (Mtb), sigue siendo una de las principales causas infecciosas de morbilidad y mortalidad a nivel mundial. Objetivo: señalar la susceptibilidad de los pacientes diabéticos frente a la tuberculosis, desde una perspectiva inmunológica. Metodología: utilizada incluyó una revisión bibliográfica exhaustiva utilizando bases de datos de alto impacto como PubMed, Google Scholar, y otras fuentes relevantes en el campo. Resultados: los pacientes diabéticos muestran una respuesta inmunológica alterada caracterizada por una función comprometida de los macrófagos y células T, y una reducción en la producción de péptidos antimicrobianos. Estos factores contribuyen a una mayor carga bacteriana y a un entorno propicio para la proliferación de Mycobacterium tuberculosis. Conclusiones: La diabetes mellitus intensifica la susceptibilidad a la tuberculosis a través de múltiples disfunciones inmunológicas. Es esencial integrar el manejo de la glucemia y la vigilancia inmunológica en el tratamiento de pacientes diabéticos con tuberculosis para mejorar los resultados clínicos y disminuir la incidencia de la enfermedad. &nbsp

    Description of a novel adhesin of Mycobacterium avium subsp. paratuberculosis

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    The binding and ingestion of Mycobacterium avium subsp. paratuberculosis (MAP) by host cells are fibronectin (FN) dependent. In several species of mycobacteria, a specific family of proteins allows the attachment and internalization of these bacteria by epithelial cells through interaction with FN. Thus, the identification of adhesion molecules is essential to understand the pathogenesis of MAP. The aim of this study was to identify and characterize FN binding cell wall proteins of MAP. We searched for conserved adhesins within a large panel of surface immunogenic proteins of MAP and investigated a possible interaction with FN. For this purpose, a cell wall protein fraction was obtained and resolved by 2D electrophoresis. The immunoreactive spots were identified by MALDI-TOF MS and a homology search was performed. We selected elongation factor Tu (EF-Tu) as candidate for further studies. We demonstrated the FN-binding capability of EF-Tu using a ligand blot assay and also confirmed the interaction with FN in a dose-dependent manner by ELISA. The dissociation constant of EF-Tu was determined by surface plasmon resonance and displayed values within the μM range. These data support the hypothesis that this protein could be involved in the interaction of MAP with epithelial cells through FN binding.Fil: Viale, Mariana Noelia. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Echeverria Valencia, Gabriela Fernanda. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Romasanta, Pablo Nicolas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Estudios de la Inmunidad Humoral Prof. Ricardo A. Margni. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Estudios de la Inmunidad Humoral Prof. Ricardo A. Margni; ArgentinaFil: Mon, Maria Laura. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Fernández, Marisa Mariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Estudios de la Inmunidad Humoral Prof. Ricardo A. Margni. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Estudios de la Inmunidad Humoral Prof. Ricardo A. Margni; ArgentinaFil: Malchiodi, Emilio Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Estudios de la Inmunidad Humoral Prof. Ricardo A. Margni. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Estudios de la Inmunidad Humoral Prof. Ricardo A. Margni; ArgentinaFil: Romano, Maria Isabel. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gioffré, Andrea Karina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Santangelo, María de la Paz. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    Production and evaluation of a purified protein derivative from an Argentine strain of Mycobacterium avium subsp. paratuberculosis (MAP)

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    Los derivados proteicos purificados (PPD) son mezclas antigénicas no definidas obtenidas de distintas micobacterias. Los PPD bovino (PPDb) y PPD aviar (PPDa) son los antígenos que se emplean para evaluar la respuesta inmunitaria celular en infecciones como tuberculosis y paratuberculosis en el bovino. El PPDa comercial se produce a partir de Mycobacterium avium subsp. avium, y no a partir de la subespecie paratuberculosis. En este trabajo se seleccionó una cepa local de Mycobacterium avium subsp. paratuberculosis cuyo patrón molecular por RFLP es el más frecuente entre los aislamientos de nuestro país que han sido estudiados, y a partir de esta, se obtuvo un derivado proteico purificado: PPDj-IB. Se emplearon tanto el PPDa comercial como el PPDj-IB como antígenos en la prueba de liberación de gamma-interferón en animales de un tambo con paratuberculosis y en animales control. Aun cuando ambos PPD fueron capaces de estimular diferencialmente la liberación de la citoquina en el tambo infectado (respecto de los tambos control), no hubo diferencias significativas en los niveles de estimulación producidos y solo dos animales fueron positivos mediante el empleo de PPDj-IB. A partir del análisis por Western blot se demostró que el contenido de lipoarabinomano y del antígeno Apa/ModD era distinto en los PDD evaluados. Estas diferencias podrían explicar, en parte, las diferencias en los niveles de estimulación en términos individuales. Si bien el empleo de PPDj-IB no mejoró significativamente los resultados de la prueba de liberación de γIFN, es importante destacar que se logró producir en el laboratorio un PPD apto para su empleo en ensayos in vitro.Purified Protein Derivatives (PPDs) are non-defined antigens prepared from mycobacteria cultures. They are usually employed to evaluate the specific cellular immune response both in animals and humans. Bovine and avian PPDs are usually employed as antigens in mycobacterial infections such as tuberculosis and paratuberculosis. Nevertheless, PPD from Mycobacterium avium subsp. paratuberculosis, (PPDj) is neither commonly used nor frequently available. However, PPD from Mycobacterium avium subsp. avium is in fact used. We aimed to obtain and evaluate the performance of a PPDj from a local isolate of MAP using the ãInterferon-release assay. The stimulation of ãInterferon-release was significantly different between infected and control cattle when this antigen, named PPDj-IB, was used. Stimulation in the infected animals was similar with both antigens (PPDa and PPDj-IB). However, some animals were positively stimulated with PPDj-IB and not with PPDa. We demonstrated by Western blot that two antigenic molecules, lipoarabinoman and APA/ModD antigen were differentially represented in both PPDs. This could explain the difference in stimulation induction of yIFN observed at individual level. Although PPDj-IB could not improve PPDa performance, we could easily produce an effective purified protein derivative for in vitro assays.Fil: Gioffré, Andrea Karina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; ArgentinaFil: Echeverria Valencia, Gabriela Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; ArgentinaFil: Zumárraga, Martín José. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; ArgentinaFil: Morsella, Claudia. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Departamento de Producción Animal; ArgentinaFil: Mon, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; ArgentinaFil: Viale, Mariana Noelia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; ArgentinaFil: Paolicchi, Fernando Alberto. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Departamento de Producción Animal; ArgentinaFil: Romano, Maria Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentin

    Global variation in postoperative mortality and complications after cancer surgery: a multicentre, prospective cohort study in 82 countries

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    © 2021 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 licenseBackground: 80% of individuals with cancer will require a surgical procedure, yet little comparative data exist on early outcomes in low-income and middle-income countries (LMICs). We compared postoperative outcomes in breast, colorectal, and gastric cancer surgery in hospitals worldwide, focusing on the effect of disease stage and complications on postoperative mortality. Methods: This was a multicentre, international prospective cohort study of consecutive adult patients undergoing surgery for primary breast, colorectal, or gastric cancer requiring a skin incision done under general or neuraxial anaesthesia. The primary outcome was death or major complication within 30 days of surgery. Multilevel logistic regression determined relationships within three-level nested models of patients within hospitals and countries. Hospital-level infrastructure effects were explored with three-way mediation analyses. This study was registered with ClinicalTrials.gov, NCT03471494. Findings: Between April 1, 2018, and Jan 31, 2019, we enrolled 15 958 patients from 428 hospitals in 82 countries (high income 9106 patients, 31 countries; upper-middle income 2721 patients, 23 countries; or lower-middle income 4131 patients, 28 countries). Patients in LMICs presented with more advanced disease compared with patients in high-income countries. 30-day mortality was higher for gastric cancer in low-income or lower-middle-income countries (adjusted odds ratio 3·72, 95% CI 1·70–8·16) and for colorectal cancer in low-income or lower-middle-income countries (4·59, 2·39–8·80) and upper-middle-income countries (2·06, 1·11–3·83). No difference in 30-day mortality was seen in breast cancer. The proportion of patients who died after a major complication was greatest in low-income or lower-middle-income countries (6·15, 3·26–11·59) and upper-middle-income countries (3·89, 2·08–7·29). Postoperative death after complications was partly explained by patient factors (60%) and partly by hospital or country (40%). The absence of consistently available postoperative care facilities was associated with seven to 10 more deaths per 100 major complications in LMICs. Cancer stage alone explained little of the early variation in mortality or postoperative complications. Interpretation: Higher levels of mortality after cancer surgery in LMICs was not fully explained by later presentation of disease. The capacity to rescue patients from surgical complications is a tangible opportunity for meaningful intervention. Early death after cancer surgery might be reduced by policies focusing on strengthening perioperative care systems to detect and intervene in common complications. Funding: National Institute for Health Research Global Health Research Unit

    Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

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    © 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licenseBackground: Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide. Methods: A multimethods analysis was performed as part of the GlobalSurg 3 study—a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital. Findings: Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3·85 [95% CI 2·58–5·75]; p<0·0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63·0% vs 82·7%; OR 0·35 [0·23–0·53]; p<0·0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer. Interpretation: Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised. Funding: National Institute for Health and Care Research
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