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1.
Int J Mol Sci ; 25(7)2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38612423

RESUMO

Periodontitis, characterized by persistent inflammation in the periodontium, is intricately connected to systemic diseases, including oral cancer. Bacteria, such as Porphyromonas gingivalis and Fusobacterium nucleatum, play a pivotal role in periodontitis development because they contribute to dysbiosis and tissue destruction. Thus, comprehending the interplay between these bacteria and their impacts on inflammation holds significant relevance in clinical understanding and treatment advancement. In the present work, we explored, for the first time, their impacts on the expressions of pro-inflammatory mediators after infecting oral keratinocytes (OKs) with a co-culture of pre-incubated P. gingivalis and F. nucleatum. Our results show that the co-culture increases IL-1ß, IL-8, and TNF-α expressions, synergistically augments IL-6, and translocates NF-kB to the cell nucleus. These changes in pro-inflammatory mediators-associated with chronic inflammation and cancer-correlate with an increase in cell migration following infection with the co-cultured bacteria or P. gingivalis alone. This effect depends on TLR4 because TLR4 knockdown notably impacts IL-6 expression and cell migration. Our study unveils, for the first time, crucial insights into the outcomes of their co-culture on virulence, unraveling the role of bacterial interactions in polymicrobial diseases and potential links to oral cancer.


Assuntos
Neoplasias Bucais , Periodontite , Humanos , Técnicas de Cocultura , Interleucina-6 , Receptor 4 Toll-Like , Inflamação , Mediadores da Inflamação , Queratinócitos
2.
Sci Total Environ ; 874: 162310, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-36828068

RESUMO

A pilot annual monitoring survey (April 2018-March 2019) was conducted to investigate the presence of pesticides in superficial water and fish in Laguna del Cisne, one of the most critical drinking water sources in Uruguay. A total of 25 pesticide residues were detected in superficial water (89.3 % of the samples). Pesticide's temporal distribution was associated with crops and livestock practices, with higher occurrences in spring and summer than in autumn and winter. The most frequent compounds in superficial water were the insecticide chlorantraniliprole, and the herbicides glyphosate (including its metabolite AMPA) and metolachlor. The levels of Organochlorine pesticide, p,p'-DDT, was in some cases two order of magnitude above the international water quality guidelines for Ambient Water Criteria. In fishes, eight different pesticides were detected, at concentrations from 1000 to 453,000 ng·kg-1. The most frequent pesticides found were propiconazole, chlorpyrifos, and p,p'-DDE. The widespread occurrence of pesticides in fish suggests potential exposure effects on fish populations and the aquatic ecosystem. The sampling approach of this work allowed monitoring the continuous concentrations of several pesticides in surface waters and fishes to establish the influence from past and current agriculture practices in Laguna del Cisne basin. For safety measures, continuous monitoring programs must be performed in this system to prevent toxicity impacts on aquatic organisms and human health.


Assuntos
Água Potável , Hidrocarbonetos Clorados , Praguicidas , Poluentes Químicos da Água , Animais , Humanos , Praguicidas/análise , Lagos , Uruguai , Ecossistema , Poluentes Químicos da Água/análise , Hidrocarbonetos Clorados/análise , DDT , Diclorodifenil Dicloroetileno , Monitoramento Ambiental
3.
Gac Med Mex ; 158(Supl 1): 38-44, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37734044

RESUMO

The objective of this work is to generate recommendations on the management of allogeneic stem cell transplantation (allo-SCT) in primary myelofibrosis (PMF). A comprehensive systematic review of articles published between 1999 and 2015 (January) was used as a source of scientific evidence. The recommendations were produced through a Delphi process involving a panel of 23 experts appointed by the European LeukemiaNet and the European Blood and Marrow Transplantation Group. Key questions included patient selection, donor selection, pre-transplant management, conditioning regimen, post-transplant management, prevention, and management of post-transplant relapse. Patients with intermediate-2 or high-risk disease and age < 70 years should be considered candidates for allo-SCT. Patients with intermediate-risk 1 disease and age < 65 years should be considered candidates if they have refractory transfusion-dependent anemia, or a peripheral blood (PB) blast percentage > 2%, or adverse cytogenetics. Splenectomy before transplantation must be decided on a case-by-case basis. Patients with intermediate-2 or high-risk disease who lack a human leukocyte antigen (HLA)-matched sibling or unrelated donor should be enrolled in a protocol that uses HLA non-identical donors. PB was considered the most appropriate source of hematopoietic stem cells for transplants from HLA-matched unrelated donors and siblings. The optimal intensity of the conditioning regimen has yet to be defined. Strategies such as discontinuation of immunosuppressive drugs, infusion of donor lymphocytes, or both were considered adequate to prevent clinical relapse. In conclusion, we provide consensus-based recommendations aimed at optimizing allo-SCT in PMF. Unmet clinical needs were highlighted.


El objetivo de este trabajo es generar recomendaciones sobre el manejo del trasplante alogénico de células madre (alo-SCT) en la mielofibrosis primaria (MFP). Se utilizó una revisión sistemática integral de artículos publicados entre 1999 y 2015 (enero) como fuente de evidencia científica. Las recomendaciones se produjeron mediante un proceso Delphi en el que participó un panel de 23 expertos designados por la European LeukemiaNet y el European Blood and Marrow Transplantation Group. Las preguntas clave incluyeron la selección de pacientes, la selección de donantes, el manejo previo al trasplante, el régimen de acondicionamiento, el manejo posterior al trasplante, la prevención y el manejo de la recaída después del trasplante. Los pacientes con enfermedad de riesgo intermedio 2 o alto y edad < 70 años deben ser considerados candidatos para alo-SCT. Los pacientes con enfermedad de riesgo intermedio 1 y edad < 65 años deben ser considerados candidatos si presentan anemia refractaria dependiente de transfusiones, o un porcentaje de blastos en sangre periférica > 2%, o citogenética adversa. La esplenectomía previa al trasplante debe decidirse caso por caso. Los pacientes con enfermedad de riesgo intermedio 2 o alto que carecen de un hermano compatible con el antígeno leucocitario humano (HLA) o de un donante no emparentado deben inscribirse en un protocolo que utilice donantes no idénticos de HLA. PB se consideró la fuente más apropiada de células madre hematopoyéticas para trasplantes de hermanos y donantes no emparentados compatibles con HLA. La intensidad óptima del régimen de acondicionamiento aún debe definirse. Se consideraron adecuadas estrategias como la suspensión de los fármacos inmunosupresores, la infusión de linfocitos del donante o ambas para evitar la recaída clínica. En conclusión, proporcionamos recomendaciones basadas en consenso destinadas a optimizar el alo-SCT en MFP. Se destacaron las necesidades clínicas insatisfechas.

4.
Gac Med Mex ; 158(Supl 1): 17-25, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37734042

RESUMO

Essential thrombocythemia (ET) is a chronic Philadelphia-negative myeloproliferative neoplasm that has its main involvement in the megakaryopoietic lineage, generating sustained thrombocytosis in peripheral blood and an increase in the number of mature megakaryocytes in the bone marrow. In addition to marked thrombocytosis, it is characterized by increased thrombotic or hemorrhagic risk and the presence of constitutional symptoms. Patients with ET have a low but known risk of disease progression to myelofibrosis and/or acute leukemia. The diagnosis is made based on the 2016 WHO criteria. At present, available treatments for patients with ET are mainly aimed at minimizing the risk of thrombosis and/or bleeding.


La trombocitemia esencial (TE) es una neoplasia mieloproliferativa crónica Filadelfia negativa que tiene su principal involucro en la línea megacariopoyética, generando trombocitosis sostenida en la sangre periférica y un incremento en el número de megacariocitos maduros en médula ósea. Además de una marcada trombocitosis, se caracteriza por un mayor riesgo trombótico o hemorrágico y la presencia de síntomas constitucionales. Los pacientes con TE tienen un riesgo bajo, pero conocido, de evolución de la enfermedad a mielofibrosis y/o leucemia aguda. El diagnóstico se realiza con base en los criterios de la Organización Mundial de la Salud del 2016. Los tratamientos actualmente disponibles para los pacientes con TE están dirigidos principalmente a minimizar el riesgo de trombosis y/o hemorragia.

5.
Gac Med Mex ; 158(Supl 1): 59-62, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37734045

RESUMO

Myeloproliferative neoplasms (MPN) are associated with a significant risk of thrombosis and the hypercoagulable environment of pregnancy increases this risk. The most frequent gestational complications consist of spontaneous abortion, thrombosis, bleeding, and hypertensive disease of pregnancy. Treatment depends on thrombotic risk, gestational trimester, and myeloproliferative neoplasm.


Las neoplasias mieloproliferativas (NMP) están asociadas a un riesgo notable de trombosis y el entorno de hipercoagulabilidad propio del embarazo aumenta este riesgo. Las complicaciones gestacionales más frecuentes consisten en: aborto espontáneo, trombosis, sangrado y enfermedad hipertensiva del embarazo. El tratamiento depende del riesgo trombótico, trimestre gestacional y neoplasia mieloproliferativa.

6.
Gac Med Mex ; 158(Supl 1): 11-16, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37734046

RESUMO

Polycythemia vera (PV) is mainly characterized by erythrocytosis, thrombotic and hemorrhagic predisposition, a variety of symptoms, and cumulative risks of fibrotic progression and/or leukemic evolution over time. The diagnosis is made based on the 2016 WHO criteria. The treatment of PV focuses on rapidly reducing the erythrocyte mass, either by means of phlebotomies or with cytoreductive treatment, and the reduction of thrombotic risk by correcting cardiovascular risk factors and the use of platelet antiaggregants.


La policitemia vera (PV) se caracteriza principalmente por eritrocitosis, predisposición trombótica y hemorrágica, una variedad de síntomas y riesgos acumulativos de progresión fibrótica y/o evolución leucémica a lo largo del tiempo. El diagnóstico se realiza con base en los criterios de la Organización Mundial de la Salud del 2016. El tratamiento de la PV se centra en reducir rápidamente la masa eritrocitaria, ya sea por medio de flebotomías o con tratamiento citorreductor, y la disminución del riesgo trombótico mediante la corrección de factores de riesgo cardiovascular y el uso de antiagregantes plaquetarios.

7.
Gac Med Mex ; 158(Supl 1): 63-65, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37734049

RESUMO

Patients with myeloproliferative neoplasms have an increased risk of thrombosis and bleeding. This risk must be identified, as well as individualizing the therapeutic strategy before invasive procedures; adequate cytoreduction reduces the risk of complications.


Los pacientes con neoplasias mieloproliferativas tienen un riesgo incrementado de trombosis y sangrado. Se debe identificar dicho riesgo, así como individualizar la estrategia terapéutica previo a los procedimientos invasivos; una adecuada citorreducción disminuye el riesgo de complicaciones.

8.
Gac Med Mex ; 158(Supl 1): 55-58, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37734050

RESUMO

In addition to symptoms secondary to splenomegaly, microvascular abnormalities, and thrombohemorrhagic complications, patients with MPN may experience a significant symptom burden attributed to an increase in circulating inflammatory cytokines. These symptoms can be severe and limit quality of life. Therefore, in addition to the prevention of complications, one of the objectives of the treatment of MPN is the control of symptoms.


Además de la sintomatología secundaria a la esplenomegalia, a las alteraciones microvasculares y a las complicaciones trombohemorrágicas, los pacientes con neoplasias mieloproliferativas (NMP) pueden experimentar una importante carga sintomática atribuida a un aumento de citocinas inflamatorias circulantes. Estos síntomas pueden ser severos y limitar la calidad de vida. Por ello, además de la prevención de las complicaciones, uno de los objetivos del tratamiento de las NMP es el control de los síntomas.

9.
Gac Med Mex ; 158(Supl 1): 45-54, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37734051

RESUMO

Major thrombotic complications in myeloproliferative neoplasms (MPNs) represent an important clinical problem due to their high morbidity, the complexity of their management, and their associated mortality. The appearance of a thrombosis implies a high thrombotic risk stratification of the MPN and determines the initiation or optimization of cytoreductive treatment and the use of antiplatelet or anticoagulant therapy as secondary prophylaxis. The incidence of thrombosis at the time of diagnosis is higher than during the course of the disease, being located in the arterial territory in 60-70% of cases. Once thrombosis has occurred, up to 20-33% of patients experience thrombotic recurrence in the same initial vascular territory.


Las complicaciones trombóticas mayores en las neoplasias mieloproliferativas (NMP) representan un importante problema clínico debido a su elevada morbilidad, la complejidad de su manejo y su mortalidad asociada. La aparición de una trombosis comporta una estratificación de alto riesgo trombótico de la NMP y determina el inicio o la optimización del tratamiento citorreductor y el uso de terapia antiplaquetaria o anticoagulante como profilaxis secundaria. La incidencia de trombosis en el momento del diagnóstico es mayor que durante la evolución de la enfermedad, localizándose en territorio arterial en el 60-70% casos. Una vez se ha producido una trombosis, hasta el 20-33% de los pacientes sufre una recurrencia trombótica en el mismo territorio vascular inicial.

10.
Gac Med Mex ; 158(Supl 1): 1-10, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37734052

RESUMO

The objective of the consensus is to make available to the professionals of the different public health institutions in our country, who are in charge of these diseases, the most relevant and up-to-date information about their diagnosis and treatment in clinical practice. With this inter-institutional consensus we hope to contribute to improving the quality of care for patients with chronic myeloproliferative neoplasms throughout the Mexican Republic, to unify criteria in both diagnosis and treatment of the different myeloproliferative diseases.


OBJETIVO: El objetivo del consenso es poner a disposición de los profesionales de las diferentes instituciones de salud pública en nuestro país, quienes se encuentran a cargo de estas enfermedades, la información más relevante y actualizada acerca de su diagnóstico y tratamiento en la práctica clínica. Con este consenso interinstitucional esperamos contribuir a mejorar la calidad de la atención de los pacientes con neoplasias mieloproliferativas crónicas a todo lo ancho y largo de la República Mexicana, con el fin de unificar criterios tanto en diagnóstico como en tratamiento de las diferentes enfermedades mieloproliferativas.

11.
Gac Med Mex ; 158(Supl 1): 26-37, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37734057

RESUMO

Myelofibrosis (MF) is a BCR-ABL1-negative myeloproliferative neoplasm characterized by clonal myeloproliferation, dysregulated kinase signaling, and release of abnormal cytokines. In recent years, important progress has been made in the knowledge of the molecular biology and the prognostic assessment of MF. Conventional treatment has limited impact on the patients' survival; it includes a wait-and-see approach for asymptomatic patients, erythropoiesis-stimulating agents, androgens, or immunomodulatory agents for anemia, cytoreductive drugs such as hydroxyurea for the splenomegaly and constitutional symptoms, and splenectomy or radiotherapy in selected patients. The discovery of the Janus kinase (JAK) 2 mutation triggered the development of molecular targeted therapy of MF. The JAK inhibitors are effective in both JAK2-positive and JAK2-negative MF; one of them, ruxolitinib, is the current best available therapy for MF splenomegaly and constitutional symptoms. Although ruxolitinib has changed the therapeutic scenario of MF, there is no clear indication of a disease-modifying effect. Allogeneic stem cell transplantation remains the only curative therapy of MF, but due to its associated morbidity and mortality, it is usually restricted to eligible high- and intermediate-2-risk MF patients. To improve current therapeutic results, the combination of JAK inhibitors with other agents is currently being tested, and newer drugs are being investigated.


La mielofibrosis (MF) es una neoplasia mieloproliferativa negativa para BCR-ABL1 caracterizada por mieloproliferación clonal, señalización de cinasa desregulada y liberación de citocinas anormales. En los últimos años se han realizado importantes avances en el conocimiento de la biología molecular y la valoración pronóstica de la MF. El tratamiento convencional tiene un impacto limitado en la supervivencia de los pacientes; incluye un enfoque de espera para pacientes asintomáticos, agentes estimulantes de la eritropoyesis, andrógenos o agentes inmunomoduladores para la anemia, fármacos citorreductores como la hidroxiurea para la esplenomegalia y los síntomas constitucionales, y esplenectomía o radioterapia en pacientes seleccionados. El descubrimiento de la mutación Janus cinasa (JAK) 2 desencadenó el desarrollo de la terapia dirigida molecular de la MF. Los inhibidores de JAK son efectivos tanto en MF con JAK2 positivo como con JAK2 negativo; uno de ellos, el ruxolitinib, es la mejor terapia disponible actualmente para la esplenomegalia y los síntomas constitucionales de la MF. Sin embargo, aunque el ruxolitinib ha cambiado el escenario terapéutico de la MF, no hay indicios claros de un efecto modificador de la enfermedad. El alotrasplante de células madre sigue siendo la única terapia curativa de la MF, pero debido a su morbilidad y mortalidad asociadas, generalmente se restringe a pacientes elegibles con MF de riesgo alto e intermedio 2. Para mejorar los resultados terapéuticos actuales, actualmente se está probando la combinación de inhibidores de JAK con otros agentes y se están investigando fármacos más nuevos.

12.
PLoS Comput Biol ; 16(5): e1007930, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32469859

RESUMO

Phenotypic delay-the time delay between genetic mutation and expression of the corresponding phenotype-is generally neglected in evolutionary models, yet recent work suggests that it may be more common than previously assumed. Here, we use computer simulations and theory to investigate the significance of phenotypic delay for the evolution of bacterial resistance to antibiotics. We consider three mechanisms which could potentially cause phenotypic delay: effective polyploidy, dilution of antibiotic-sensitive molecules and accumulation of resistance-enhancing molecules. We find that the accumulation of resistant molecules is relevant only within a narrow parameter range, but both the dilution of sensitive molecules and effective polyploidy can cause phenotypic delay over a wide range of parameters. We further investigate whether these mechanisms could affect population survival under drug treatment and thereby explain observed discrepancies in mutation rates estimated by Luria-Delbrück fluctuation tests. While the effective polyploidy mechanism does not affect population survival, the dilution of sensitive molecules leads both to decreased probability of survival under drug treatment and underestimation of mutation rates in fluctuation tests. The dilution mechanism also changes the shape of the Luria-Delbrück distribution of mutant numbers, and we show that this modified distribution provides an improved fit to previously published experimental data.


Assuntos
Evolução Biológica , Farmacorresistência Bacteriana/genética , Modelos Genéticos , Mutação , Fenótipo , Poliploidia
13.
Sci Rep ; 7: 41515, 2017 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-28128355

RESUMO

Antibody light chain amyloidosis is a rare disease caused by fibril formation of secreted immunoglobulin light chains (LCs). The huge variety of antibody sequences puts a serious challenge to drug discovery. The green tea polyphenol epigallocatechin-3-gallate (EGCG) is known to interfere with fibril formation in general. Here we present solution- and solid-state NMR studies as well as MD simulations to characterise the interaction of EGCG with LC variable domains. We identified two distinct EGCG binding sites, both of which include a proline as an important recognition element. The binding sites were confirmed by site-directed mutagenesis and solid-state NMR analysis. The EGCG-induced protein complexes are unstructured. We propose a general mechanistic model for EGCG binding to a conserved site in LCs. We find that EGCG reacts selectively with amyloidogenic mutants. This makes this compound a promising lead structure, that can handle the immense sequence variability of antibody LCs.


Assuntos
Amiloide/metabolismo , Catequina/análogos & derivados , Cadeias Leves de Imunoglobulina/metabolismo , Agregados Proteicos , Sequência de Aminoácidos , Amiloide/química , Sítios de Ligação , Catequina/química , Catequina/farmacologia , Precipitação Química , Humanos , Cadeias Leves de Imunoglobulina/química , Cinética , Espectroscopia de Ressonância Magnética , Mutação/genética , Prolina/metabolismo , Alinhamento de Sequência
15.
J Phys Chem B ; 120(12): 2991-9, 2016 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-26965454

RESUMO

Protein aggregation into highly structured amyloid fibrils is associated with various diseases including Alzheimer's disease, Parkinson's disease, and type II diabetes. Amyloids can also have normal biological functions and, in the future, could be used as the basis for novel nanoscale materials. However, a full understanding of the physicochemical forces that drive protein aggregation is still lacking. Such understanding is crucial for the development of drugs that can effectively inhibit aberrant amyloid aggregation and for the directed design of functional amyloids. Atomistic simulations can help understand protein aggregation. In particular, atomistic simulations can be used to study the initial formation of toxic oligomers which are hard to characterize experimentally and to understand the difference in aggregation behavior between different amyloidogenic peptides. Here, we review the latest atomistic simulations of protein aggregation, concentrating on amyloidogenic protein fragments, and provide an outlook for the future in this field.


Assuntos
Simulação de Dinâmica Molecular , Peptídeos/química , Agregados Proteicos , Amiloide/química , Humanos
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