RESUMEN
A non-porous version of SU-101 (herein n-SU-101) was evaluated for the CO2 cycloaddition reaction. The findings revealed that open metal sites (Bi3+) are necessary for the reaction. n-SU-101 displays a high styrene oxide conversion of 96.6% under mild conditions (3 bar and 80 °C). The catalytic activity of n-SU-101 demonstrated its potential application for the cycloaddition of CO2 using styrene oxide.
RESUMEN
OBJECTIVE: Mortality in pregnancy due to coronavirus disease 2019 (COVID-19) is a current health priority in developing countries. Identification of clinical and sociodemographic risk factors related to mortality in pregnant women with COVID-19 could guide public policy and encourage such women to accept vaccination. We aimed to evaluate the association of comorbidities and socioeconomic determinants with COVID-19-related mortality and severe disease in pregnant women in Mexico. METHODS: This is an ongoing nationwide prospective cohort study that includes all pregnant women with a positive reverse-transcription quantitative polymerase chain reaction result for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from the Mexican National Registry of Coronavirus. The primary outcome was maternal death due to COVID-19. The association of comorbidities and socioeconomic characteristics with maternal death was explored using a log-binomial regression model adjusted for possible confounders. RESULTS: There were 176 (1.35%) maternal deaths due to COVID-19 among 13 062 consecutive SARS-CoV-2-positive pregnant women. Maternal age, as a continuous (adjusted relative risk (aRR), 1.08 (95% CI, 1.05-1.10)) or categorical variable, was associated with maternal death due to COVID-19; women aged 35-39 years (aRR, 3.16 (95% CI, 2.34-4.26)) or 40 years or older (aRR, 4.07 (95% CI, 2.65-6.25)) had a higher risk for mortality, as compared with those aged < 35 years. Other clinical risk factors associated with maternal mortality were pre-existing diabetes (aRR, 2.66 (95% CI, 1.65-4.27)), chronic hypertension (aRR, 1.75 (95% CI, 1.02-3.00)) and obesity (aRR, 2.15 (95% CI, 1.46-3.17)). Very high social vulnerability (aRR, 1.88 (95% CI, 1.26-2.80)) and high social vulnerability (aRR, 1.49 (95% CI, 1.04-2.13)) were associated with an increased risk of maternal mortality, while very low social vulnerability was associated with a reduced risk (aRR, 0.47 (95% CI, 0.30-0.73)). Being poor or extremely poor were also risk factors for maternal mortality (aRR, 1.53 (95% CI, 1.09-2.15) and aRR, 1.83 (95% CI, 1.32-2.53), respectively). CONCLUSION: This study, which comprises the largest prospective consecutive cohort of pregnant women with COVID-19 to date, has confirmed that advanced maternal age, pre-existing diabetes, chronic hypertension, obesity, high social vulnerability and low socioeconomic status are risk factors for COVID-19-related maternal mortality. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.
Asunto(s)
COVID-19/epidemiología , Muerte Materna/estadística & datos numéricos , Complicaciones Infecciosas del Embarazo/epidemiología , Vulnerabilidad Social , Adulto , Estudios de Cohortes , Comorbilidad , Femenino , Humanos , Mortalidad Materna , México , Pobreza , Embarazo , Nacimiento Prematuro/epidemiología , Estudios ProspectivosRESUMEN
OBJECTIVE: There are limited, unmatched data reporting low complication rates in pregnant women with coronavirus disease 2019 (COVID-19). The aim of this study was to compare COVID-19-related outcomes between pregnant and non-pregnant women after adjusting for potential risk factors for severe outcomes. METHODS: Data were obtained from the COVID-19 National Data Registry of Mexico, which is an ongoing prospective cohort of people of any age with clinically suspected severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and admitted to 475 monitoring hospitals. This study included pregnant and non-pregnant women of reproductive age (15-45 years) with COVID-19 confirmed by reverse transcription polymerase chain reaction. To adjust for underlying risk factors, propensity score matching was conducted for chronic obstructive pulmonary disease, asthma, smoking, hypertension, cardiovascular disease, obesity, diabetes, chronic renal disease, immunosuppression, age, language, nationality and level of health insurance. The primary outcome was death. Secondary outcomes were pneumonia, intubation and intensive care unit (ICU) admission. RESULTS: The cohort comprised 5183 pregnant and 175 905 non-pregnant women with COVID-19. The crude (unmatched) rates of death, pneumonia, intubation and ICU admission in pregnant compared with non-pregnant women were 1.5% vs 1.5%, 9.9% vs 6.5%, 8.1% vs 9.9% and 13.0% vs 6.9%, respectively. After propensity score matching (5183 pregnant and 5183 non-pregnant matched women), pregnant women had a higher odds of death (odds ratio (OR), 1.84; 95% CI, 1.26-2.69), pneumonia (OR, 1.86; 95% CI, 1.60-2.16) and ICU admission (OR, 1.86; 95% CI, 1.41-2.45) than non-pregnant women, but similar odds of intubation (OR, 0.93; 95% CI, 0.70-1.25). CONCLUSION: After adjusting for background demographic and medical factors, pregnancy is a risk factor for death, pneumonia and ICU admission in SARS-CoV-2-infected women of reproductive age. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.
Asunto(s)
COVID-19/mortalidad , Neumonía/etiología , Complicaciones Infecciosas del Embarazo/mortalidad , Complicaciones Infecciosas del Embarazo/virología , Adolescente , Adulto , COVID-19/diagnóstico , COVID-19/virología , Estudios de Casos y Controles , Comorbilidad , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Unidades de Cuidados Intensivos/estadística & datos numéricos , México/epidemiología , Persona de Mediana Edad , Mortalidad , Pandemias , Neumonía/virología , Embarazo , Puntaje de Propensión , Estudios Prospectivos , Factores de Riesgo , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , Adulto JovenRESUMEN
Transforming growth factor-beta 1 (TGF-ß1) is a cytokine with marked pro-fibrotic action on cardiac fibroblasts (CF). TGF-ß1 induces CF-to-cardiac myofibroblast (CMF) differentiation, defined by an increase in α-smooth muscle cells (α-SMA), collagen secretion and it has a cytoprotective effect against stimuli that induce apoptosis. In the Endoplasmic Reticulum (ER) lumen, misfolded protein accumulation triggers ER stress and induces apoptosis, and this process plays a critical role in cell death mediated by Ischemia/Reperfusion (I/R) injury and by ER stress inducers, such as Tunicamycin (Tn). Here, we studied the regulation of CHOP, a proapoptotic ER-stress-related transcription factor in CF under simulated I/R (sI/R) or exposed to Tn. Even though TGF-ß1 has been shown to participate in ER stress, its regulatory effect on CF apoptosis and ER stress-induced by sI/R or TN has not been evaluated yet. CF from neonatal rats were exposed to sI/R, and cell death was evaluated by cell count and apoptosis by flow cytometry. ER stress was assessed by western blot against CHOP. Our results evidenced that sI/R (8/24) h or Tn triggers CF apoptosis and an increase in CHOP protein levels. TGF-ß1 pre-treatment partially prevented apoptosis induced by sI/R or Tn. Furthermore, TGF-ß1 pre-treatment completely prevented CHOP increase by sI/R or Tn. Additionally, we found a decrease in α-SMA expression induced by sI/R and in collagen secretion induced by Tn, which were not prevented by TGF-ß1 treatment. In conclusion, TGF-ß1 partially protects CF apoptosis induced by sI/R or Tn, through a mechanism that would involve ER stress.
Asunto(s)
Apoptosis/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Factor de Transcripción CHOP/metabolismo , Factor de Crecimiento Transformador beta1/farmacología , Actinas/metabolismo , Animales , Animales Recién Nacidos , Supervivencia Celular/efectos de los fármacos , Colágeno/metabolismo , Estrés del Retículo Endoplásmico/efectos de los fármacos , Fibroblastos/metabolismo , Daño por Reperfusión Miocárdica/metabolismo , Miocardio/citología , Ratas Sprague-Dawley , Tunicamicina/farmacologíaRESUMEN
Cardiac fibroblasts (CF) play a key role in the homeostasis of the extracellular matrix in cardiac tissue and are newly recognized as inflammatory supporter cells. Besides, CF-to-Cardiac myofibroblast differentiation is commanded by TGF-b, through SMAD signaling pathways, and these last cells are strongly implicated in cardiac fibrosis. In the heart IFN-ß is produced by CF; however, the role of IFN-ß, STAT proteins, and STAT-homo or heterodimers in the regulation of CF function with or without a fibrotic environment is unknown. CF were isolated from hearts of adult rats, and by western blot analysis we studied STAT1, STAT2, and STAT3 phosphorylation and through specific siRNA against these proteins we analyzed their role in CF functions such as differentiation (α-SMA expression); and pro-collagen type-I synthesis and secretion expression levels; collagen gels contraction and CF migration. In cultured adult rats CF, IFN-ß increases phosphorylation of STAT1, STAT2, and STAT3. Both STAT1 and STAT2 were involved in decreasing α-SMA and CF migration induced by TGF-ß1. Also, IFN-ß through STAT1 regulated pro-collagen type-I protein expression levels, and collagen gels contraction induced by TGF-ß1. STAT3 was not involved in any effects of IFN-ß studied. In conclusion, IFN-ß through STAT1 and STAT2 shows antifibrotic effects on CF TGF-ß1-treated, whereas STAT3 did not participate in such effect.
Asunto(s)
Colágeno/metabolismo , Fibroblastos/metabolismo , Regulación de la Expresión Génica , Interferón beta/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Animales , Diferenciación Celular , Movimiento Celular , Colágeno/química , Matriz Extracelular/metabolismo , Silenciador del Gen , Masculino , Miofibroblastos/efectos de los fármacos , Fosforilación , ARN Interferente Pequeño/metabolismo , Ratas , Ratas Sprague-Dawley , Factor de Transcripción STAT1/biosíntesis , Factor de Transcripción STAT2/biosíntesis , Transducción de Señal/efectos de los fármacosRESUMEN
Here, we present the mitogenome of the blood feeding leech Haementeria acuecueyetzin (Hirudinida: Glossiphoniidae) based on specimens collected in Tabasco, Mexico. The circular genome is 14,985 bp in length, and consists of 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and an AT-rich control region. Phylogenetic analysis based on the 13 protein-coding genes and two rRNA genes places H. acuecueyetzin sister to H. officinalis within the family Glossiphoniidae. Mitochondrial gene order in H. acuecueyetzin is consistent with other members of Clitellata with no evidence of gene gain/loss, duplication, or rearrangement.
RESUMEN
Breast cancer (BC) is a malignant disease with a high prevalence worldwide. The main cause of death is not the primary tumor, but instead the spread of tumor cells to distant sites. The aim of the present study was to examine a new method for the detection of cancer cells in aqueous medium using bioimpedance spectroscopy assisted with magnetic nanoparticles (MNP's) exposure to a constant magnetic field. The spectroscopic patterns were identified for three breast cancer cell lines. Each BC cell line represents a different pathologic stage: the early stage (MCF-7), invasive phase (MDA-MB-231) and metastasis (SK-BR-3). For this purpose, bioimpedance measurements were carried out at a certain frequency range with the aid of nanoprobes, consisting of magnetic nanoparticles (MNPs) coupled to a monoclonal antibody. The antibody was specific for the predominant cell surface protein for each cell line, which was identified by using RT-qPCR and flow cytometry. Accordingly, EpCAM corresponds to MCF-7, MUC-1 to MDA-MB-231, and HER-2 to SK-BR-3. Despite their low concentrations, BC cells could be detected by impedance spectroscopy. Hence, this methodology should permit the monitoring of circulating tumor cells (CTC) and therefore help to prevent recurrences and metastatic processes during BC treatment.
Asunto(s)
Técnicas Biosensibles , Neoplasias de la Mama/diagnóstico , Detección Precoz del Cáncer/métodos , Molécula de Adhesión Celular Epitelial/genética , Mucina-1/genética , Células Neoplásicas Circulantes/metabolismo , Receptor ErbB-2/genética , Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/metabolismo , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Línea Celular Tumoral , Espectroscopía Dieléctrica , Molécula de Adhesión Celular Epitelial/metabolismo , Femenino , Expresión Génica , Humanos , Metástasis Linfática , Células MCF-7 , Campos Magnéticos , Nanopartículas de Magnetita/química , Mucina-1/metabolismo , Células Neoplásicas Circulantes/patología , Receptor ErbB-2/metabolismoRESUMEN
Resumen Antecedentes: la prueba diagnóstica de referencia para endometriosis es la visualización de focos endometriósicos en un procedimiento quirúrgico. Los valores de CA-125 > 35 UI/mL y de CA-19.9 > 37 UI/mL sugieren endometriosis o tumores de ovario (teratomas, endometriomas y mucinosos). Los valores de CA-19.9 > 300 UI/mL tienen un valor predictivo positivo mayor de 90% para cáncer de páncreas. Caso clínico: paciente de 32 años de edad, con infertilidad primaria de 10 años, tumoración compleja en el ovario derecho de 209 cc y en el ovario izquierdo de 14.81 cc, con CA-19.9 de 2,920 UI/mL y CA-125 de 142.37 UI/mL. Por tomografía y panendoscopia se descartó la posibilidad de malignidad en el aparato gastrointestinal. En la laparotomía exploradora, protocolizada para tumor de ovario, se encontró un tumor de 10 x 8.0 cm en el ovario derecho y uno de 3.0 x 2.0 cm en el izquierdo. El reporte de patología fue de quistes endometriósicos, sin malignidad coexistente. En el seguimiento a los 40 días se encontró un CA-19.9 de 41.38 U/mL y a los 60 días logró un embarazo espontáneo. Conclusiones: los marcadores tumorales se utilizan para descartar algún proceso maligno en el ovario. Se carece de pruebas suficientes para recomendarlos rutinariamente para diagnosticar endometriosis. Cuando inusualmente sus valores se encuentran por encima del punto de corte, es importante descartar cualquier malignidad en el aparato gastrointestinal. Se recomienda asumir el tratamiento de estas pacientes con un equipo multidisciplinario.
Abstract Background: Endometriosis is the presence of ectopic non-neoplastic endometrial tissue. The gold standard diagnosis is a visual inspection by laparoscopy. A CA-125 >35 IU/mL and a CA-19.9 >37 IU/mL have been present in endometriosis and ovarian tumors (teratomas, endometriomas or mucinous). However, an elevation >300 IU/mL have a positive predictive value >90% for pancreatic cancer. Case report: 32-year-old female, with 10-year primary infertility. With a complex tumor in the right ovary of 209cc and in the left one of 14.81cc. The CA-19.9 was at 2,920 IU/mL and the CA-125 at 142.37 IU/mL. In which have ruled out gastrointestinal malignancy with tomography and panendoscopy. A laparotomy exploratory was performed, finding a tumor of 10x8.0cm in the right ovary and 3.0x2.0cm in the left one. The pathology report was of endometriosis cysts, with no coexisting malignancy. At follow-up at 40 days a CA-19.9 of 41.38 IU/mL was found and at 60 days achieved a spontaneous pregnancy. Conclusions: Tumor biomarkers are generally used to rule out malignant ovary pathology. There is insufficient evidence to recommend its routine use to diagnose endometriosis. However, when they are unusually above the cut-off point, it is important to specifically rule out gastrointestinal malignancy, working in a multidisciplinary way.
RESUMEN
Resumen OBJETIVO: describir el tipo de atención médica, tratamiento y seguimiento de pacientes con neoplasia intraepitelial cervical (NIC 3) y carcinoma in situ durante el embarazo, su evolución y condiciones del recién nacido. MATERIALES Y MÉTODOS: estudio retrospectivo de pacientes atendidas en el Instituto Nacional de Perinatología entre los meses de enero de 2009 y diciembre de 2014. Se incluyeron pacientes con diagnóstico de NIC 3 durante el embarazo, con expediente completo y atendidas en el servicio de Obstetricia desde su ingreso para control prenatal hasta la terminación del embarazo y tratamiento oncológico definitivo. RESULTADOS: se identificaron 6 casos de pacientes embarazadas con diagnóstico de NIC 3 posterior a la toma de citología cervical. A todas se les realizó colposcopia y biopsia cervical, sin complicaciones secundarias al procedimiento. El diagnóstico histopatológico fue: carcinoma epidermoide in situ en 3 pacientes y en otras 3 neoplasia intraepitelial cervical. Todas las pacientes recibieron atención multidisciplinaria, sin complicaciones obstétricas ni neonatales. El seguimiento promedio fue de 2 años. CONCLUSIONES: el diagnóstico oportuno de las lesiones precursoras de cáncer cervicouterino es indispensable y no se relaciona con inconvenientes perinatales derivados del tipo de acceso.
Abstract OBJECTIVE: Describe the approach, management and monitoring of patients with cervical intraepithelial neoplasia (NIC) 3 and in situ carcinoma during pregnancy, its evolution and perinatal outcomes. MATERIALS AND METHODS: We made a retrospective study of cases from January 2009 to December 2014 in women of the National Institute of Perinatology . We included patients who were diagnosed with cervical intraepithelial neoplasia 3 during pregnancy, with complete file and that received medical consultation of the oncology and obstetrics service since their admission to the hospital for prenatal control until de resolution of pregnancy and oncological definitive treatment. RESULTS: During the study period, 6 cases of pregnant patients where diagnosed with CIN 3, after cervical cytology was taken, a cervical biopsy was performed without complications secondary to this procedure; the histopathological diagnosis was: In situ epidermoid carcinoma in 3 patients and Cervical Intraepithelial Neoplasia in the other 3. All patients were treated with a Multidisciplinary approach. None of the patients presented obstetric or neonatal complications; At the end of the puerperium, follow-up was continued,the mean follow-up after the definitive treatment was 2 years. CONCLUSIONS: The timely diagnosis of precursor lesions of CACU is indispensable, in turn, is not related to adverse perinatal outcomes derived from the approach and timely screening.
RESUMEN
The present study evaluates the superoxide dismutase (SOD) and catalase (CAT) activities in a wild strain of Drosophila melanogaster and the genotoxic potential induced by Cas II-gly (a new antineoplastic drug) using the somatic mutation and recombination test. Larvae 48h old were treated with Cas II-gly in a range of 0-1.5mM and aliquot were taken every 24h to have individuals treated for 24, 48, 72h and adulthood as well. A dose-dependent toxicity and a significant increase in SOD and CAT activities were found after a 24 and 48h treatment with 0.5-1.5mM concentrations. The comparison of the effect in enzymes with mutation indicated a positive correlation with increased genetic damage, after 24 and 48h of exposure for all concentrations tested. The addition of the genetic damage induced in each exposure time showed a significant effect, but only the small single spots had a concentration-related increase.
Asunto(s)
Antineoplásicos/toxicidad , Quelantes/toxicidad , Cobre/metabolismo , Mutágenos/toxicidad , Compuestos Organometálicos/toxicidad , Estrés Oxidativo/efectos de los fármacos , Animales , Catalasa/metabolismo , Relación Dosis-Respuesta a Droga , Drosophila melanogaster/efectos de los fármacos , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Femenino , Dosificación Letal Mediana , Peroxidación de Lípido/efectos de los fármacos , Peroxidación de Lípido/genética , Masculino , Estrés Oxidativo/genética , Recombinación Genética/efectos de los fármacos , Superóxido Dismutasa/metabolismo , Alas de Animales/efectos de los fármacosRESUMEN
BACKGROUND: Chagas disease or American Trypanosomiasis is caused by the flagellated protozoan parasite Trypanosoma cruzi (T. cruzi) and is recognized by the WHO as one of the world's 17 neglected tropical diseases. Only two drugs (Benznidazol, Bz and Nifurtimox, Nx) are currently accepted for treatment, however they cause severe adverse effects and their efficacy is still controversial. It is then important to explore for new drugs. PURPOSE: Programmed cell death (PCD) in parasites offers interesting new therapeutic targets. The aim of this work was to evaluate the induction of PCD in T. cruzi by two natural sesquiterpene lactones (STLs), dehydroleucodine (DhL) and helenalin (Hln) as compared with the two conventional drugs, Bz and Nx. MATERIAL AND METHODS: Hln and DhL were isolated from aerial parts of Gaillardia megapotamica and Artemisia douglassiana Besser, respectively. Purity of compounds (greater than 95%) was confirmed by (13)C-nuclear magnetic resonance, melting point analysis, and optical rotation. Induction of PCD in T. cruzi epimastigotes and trypomastigotes by DhL, Hln, Bz and Nx was assayed by phosphatidylserine exposure at the parasite surface and by detection of DNA fragmentation using the TUNEL assay. Trypanocidal activity of natural and synthetic compounds was assayed by measuring parasite viability using the MTT method. RESULTS: The two natural STLs, DhL and Hln, induce programmed cell death in both, the replicative epimastigote form and the infective trypomastigote form of T. cruzi. Interestingly, the two conventional antichagasic drugs (Bz and Nx) do not induce programmed cell death. A combination of DhL and either Bz or Nx showed an increased effect of natural compounds and synthetic drugs on the decrease of parasite viability. CONCLUSION: DhL and Hln induce programmed cell death in T. cruzi replicative epimastigote and infective trypomastigote forms, which is a different mechanism of action than the conventional drugs to kill the parasite. Therefore DhL and Hln may offer an interesting option for the treatment of Chagas disease, alone or in combination with conventional drugs.
Asunto(s)
Apoptosis/efectos de los fármacos , Lactonas/farmacología , Sesquiterpenos/farmacología , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Animales , Artemisia/química , Chlorocebus aethiops , Estructura Molecular , Nifurtimox/farmacología , Nitroimidazoles/farmacología , Sesquiterpenos de Guayano , Células VeroRESUMEN
Hummingbirds are specialized hoverers for which the vortex wake has been described as a series of single vortex rings shed primarily during the downstroke. Recent findings in bats and birds, as well as in a recent study on Anna's hummingbirds, suggest that each wing may shed a discrete vortex ring, yielding a bilaterally paired wake. Here, we describe the presence of two discrete rings in the wake of hovering Anna's hummingbirds, and also infer force production through a wingbeat with contributions to weight support. Using flow visualization, we found separate vortices at the tip and root of each wing, with 15% stronger circulation at the wingtip than at the root during the downstroke. The upstroke wake is more complex, with near-continuous shedding of vorticity, and circulation of approximately equal magnitude at tip and root. Force estimates suggest that the downstroke contributes 66% of required weight support, whereas the upstroke generates 35%. We also identified a secondary vortex structure yielding 8-26% of weight support. Lift production in Anna's hummingbirds is more evenly distributed between the stroke phases than previously estimated for Rufous hummingbirds, in accordance with the generally symmetric down- and upstrokes that characterize hovering in these birds.
Asunto(s)
Aves/fisiología , Vuelo Animal , Movimientos del Aire , Animales , Fenómenos Biomecánicos , Aves/anatomía & histología , Alas de Animales/anatomía & histología , Alas de Animales/fisiologíaRESUMEN
Systemic lupus erythematosus (SLE) is characterized by abnormalities in the function of T and B lymphocytes and in the signaling pathways induced through their receptors. Cbl-b is an intracellular adaptor protein that plays a key role in the negative regulation of lymphocyte activity. We explored the expression and function of Cbl-b in T lymphocytes from SLE patients. In addition, the possible association of SLE and a single nucleotide polymorphism (SNP) of the Cblb gene was determined. We studied 150 SLE patients, 163 healthy individuals, and 14 patients with rheumatoid arthritis (RA). The expression of Cbl-b was analyzed in the peripheral blood mononuclear cells, and the negative regulatory function of Cbl-b was assessed by analyzing actin polymerization and the phosphorylation of JNK and c-Jun induced through CD3. Furthermore, the 2126(A/G) SNP of the Cblb gene was detected by real-time polymerase chain reaction. We found a significant small reduction in the expression of Cbl-b as well as increased levels of activation of c-Jun and actin polymerization in T lymphocytes from patients with SLE compared with healthy controls or RA patients. In addition, a significant association between the 2126(A/G) SNP and SLE was detected. Our data suggest that Cbl-b may contribute to the deregulated activation of T lymphocytes observed in SLE.
Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Lupus Eritematoso Sistémico/inmunología , Proteínas Proto-Oncogénicas c-cbl/genética , Linfocitos T/metabolismo , Actinas/metabolismo , Proteínas Adaptadoras Transductoras de Señales/inmunología , Artritis Reumatoide/genética , Artritis Reumatoide/inmunología , Estudios de Casos y Controles , Humanos , Leucocitos Mononucleares/metabolismo , Lupus Eritematoso Sistémico/genética , México , Fosforilación , Reacción en Cadena de la Polimerasa , Polimerizacion , Polimorfismo de Nucleótido Simple , Proteínas Proto-Oncogénicas c-cbl/inmunología , Proteínas Proto-Oncogénicas c-jun/metabolismoRESUMEN
Epidemiological studies demonstrate an association between chronic consumption of arsenic contaminated water and cognitive deficits, especially when the exposure takes place during childhood. This study documents structural changes and nitrergic deficits in the striatum of adult female Wistar rats exposed to arsenic in drinking water (3 ppm, approximately 0.4 mg/kg per day) from gestation, throughout lactation and development until the age of 4 months. Kainic acid injected animals (10mg/kg, i.p.) were also analyzed as positive controls of neural cell damage. Morphological characteristics of cells, fiber tracts and axons were analyzed by means of light microscopy as well as immunoreactivity to neuronal nitric oxide synthase (nNOS). As nitrergic markers, nitrite/nitrate concentrations, nNOS levels and expression of nNOS-mRNA were quantified in striatal tissue. Reactive oxygen species (ROS) and lipid peroxidation (LPx) were determined as oxidative stress markers. Arsenic exposure resulted in moderate to severe alterations of thickness, organization, surrounding space and shape of fiber tracts and axons, while cell bodies remained healthy. These anomalies were not accompanied by ROS and/or LPx increases. By contrast, except the expression of nNOS-mRNA, all nitrergic markers including striatal nNOS immunoreactivity presented a significant decrease. These results indicate that arsenic targets the central nitrergic system and disturbs brain structural organization at low exposure levels.
Asunto(s)
Arsenitos/toxicidad , Cuerpo Estriado/efectos de los fármacos , Neuronas Nitrérgicas/efectos de los fármacos , Óxido Nítrico/metabolismo , Efectos Tardíos de la Exposición Prenatal , Compuestos de Sodio/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Cuerpo Estriado/enzimología , Cuerpo Estriado/patología , Agonistas de Aminoácidos Excitadores/toxicidad , Femenino , Edad Gestacional , Ácido Kaínico/toxicidad , Lactancia , Peroxidación de Lípido/efectos de los fármacos , Nitratos/metabolismo , Neuronas Nitrérgicas/enzimología , Neuronas Nitrérgicas/patología , Óxido Nítrico Sintasa/metabolismo , Óxido Nítrico Sintasa de Tipo I , Nitritos/metabolismo , Embarazo , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Trypanosoma cruzi, a parasitic protozoan, is the agent of Chagas' disease or American trypanosomiasis, an endemic pathology in Latin America, affecting up to 18 million people, with high public health costs. Programmed cell death (PCD) has many functions in development and tissue remodeling in metazoans. In protozoa, it could represent concomitant or alternative mechanisms for clonal selection, immune response evasion, and population size regulation. In this work, we describe the natural occurrence of PCD in T. cruzi epimastigotes during the stationary phase of growth in axenic culture or under nutrient deprivation. Thus, we have observed phosphatidylserine externalization, cellular volume decrease, caspase-like protein activity, and DNA fragmentation. Additionally, serum deprivation also induces autophagic characteristics such as monodansylcadaverine-labeled vesicles accumulation and redistribution of proteins homologous to Atg8. In agreement with our results, apoptosis may play an important role in parasite survival. Then, identification and modulation of molecular targets inducing programmed cell death in T. cruzi may lead to new potential therapeutic approaches for Chagas' disease.
Asunto(s)
Apoptosis , Trypanosoma cruzi/crecimiento & desarrollo , Animales , Caspasas/metabolismo , Células Cultivadas , Enfermedad de Chagas/inmunología , Enfermedad de Chagas/parasitología , Fosfatidilserinas/metabolismo , Proteínas Protozoarias/metabolismo , Trypanosoma cruzi/metabolismoRESUMEN
Se realizó una revisión bibliográfica con el objetivo de proponer un material de consulta dirigido a profesores, por la importancia de la vinculación de los contenidos de acuerdo con el perfil de salida del egresado y de los campos de acción y esferas de actuación en los que se desempeñarán los estudiantes, encaminado a alcanzar la vinculación de la teoría con la práctica y estimular la independencia y la creatividad del estudiante en el proceso del desarrollo de habilidades y conocimientos.(AU)
Asunto(s)
Educación Profesional , Educación Basada en CompetenciasRESUMEN
Echinococcus granulosus is a parasitic cestode causing hydatidosis in intermediate hosts (human and herbivorous). Most symptoms of the disease occur by the pressure exerted on viscera by cysts that are formed upon ingestion of the parasite eggs excreted by definitive hosts (canines). Protoscoleces, the developmental form of the parasite infective to definitive hosts, are formed in the germinal nucleated layer of fertile hydatid cysts. For unknown reasons, some cysts are unable to produce protoscoleces (infertile hydatid cysts). In this study, analysis of DNA fragmentation using TUNEL and agarose gel electrophoresis showed higher levels of apoptosis in infertile cysts as compared to fertile cysts. Additionally, caspase 3 was detected both in fertile and infertile cysts; the activity of this enzyme was found to be higher in infertile cysts. We conclude that apoptosis may be involved in hydatid cyst infertility. This is the first report on the presence of programmed cell death in E. granulosus.
Asunto(s)
Apoptosis , Equinococosis Hepática/metabolismo , Equinococosis Pulmonar/metabolismo , Echinococcus granulosus/fisiología , Infertilidad , Animales , Caspasa 3/metabolismo , Bovinos , Equinococosis Hepática/parasitología , Equinococosis Pulmonar/parasitología , Echinococcus granulosus/aislamiento & purificación , Etiquetado Corte-Fin in SituRESUMEN
Embryogenic callus and suspension cultures of carrot (Daucus carota L., cv. Nantaise), growing on/in medium including 1 mg/l 2,4-dichlorophenoxy acetic acid (2,4-D), were transferred to medium with or without this plant growth regulator, to impair or induce, respectively, further development of somatic embryos. The endogenous hormone levels of the cultures were determined over 7 days by means of radio-immunoassay, to characterize their evolution in the initial stages of embryo development. In general, levels of indoleacetic acid (IAA) and abscisic acid (ABA) showed only short-lived differences among treatments during this time in both types of tissue analyzed (i.e., a peak of IAA in callus cultures in the absence of 2,4-D, 48 h after medium change, and higher ABA contents 144 h after subculture of suspension cultures in the presence of 2,4-D). Gibberellins (1, 3 and 20) were detected only in suspension cultures devoid of 2,4-D, starting 24 h after subculture. Concerning the evaluated cytokinins-zeatin/zeatin riboside and N6(Delta2-isopentenyl) adenine/N6(Delta2-isopentenyl) adenosine-the most remarkable observation is that high levels of the former generally coincided with low concentrations of the latter, indicating a shift from precursor to the active form, and vice versa.
Asunto(s)
Daucus carota/crecimiento & desarrollo , Reguladores del Crecimiento de las Plantas/fisiología , Ácido 2,4-Diclorofenoxiacético/farmacología , Técnicas de Cultivo de Célula/métodos , Daucus carota/efectos de los fármacos , Hipocótilo/efectos de los fármacos , Hipocótilo/fisiología , Ácidos Indolacéticos/farmacología , Reguladores del Crecimiento de las Plantas/farmacologíaRESUMEN
Introducción: Desde la introducción de la hemodiálisis por Kolff en 1944, se abre un nuevo camino para los enfermos renales crónicos, sin embargo, persistía un problema sin resolver: un acceso arterial y venoso confiable que Brescia resuelve en 1966, con la introducción de la fístula arteriovenosa radiocefálica, asegurando accesos vasculares expeditos, duraderos y eficientes en relación con el territorio vascular intervenido. Material y Método: Se analizan en forma retrospectiva, las fichas clínicas de 166 pacientes, 101 (60,84 por ciento) hombres y 65 (39,15 por ciento) mujeres, a quienes se les realizó una FAV en el período comprendido entre 01/01/1990 y 31/12/1999, con técnica estandarizada utilizando lidocaína 2 por ciento como anestésico local, anastomosis término-lateral de vena-arteria, arteriotomía en longitud 2,5 veces el diámetro de la arteria y profilaxis con Cloxacilina 1 g ev 30 minutos preoperatorio completando 24 horas con tratamiento oral (500 mg c/6 horas). Resultados: El tiempo medio de enfermedad fue de 7 años fluctuando entre 1 y 30. En 95 por ciento de los casos (158 pacientes), se realizó FAV radiocefálica, localización más frecuente muñeca izquierda en 98 casos (59,63 por ciento) sguida de la derecha en 60 casos (36,14 por ciento), las 8 restantes localizaciones se deben a la anatomía del paciente. Complicaciones técnicas hubo en 36 casos; en 22 casos (13,25 por ciento) fibrosis del territorio venoso. Hubo complicaciones en 35 pacientes, siendo la más frecuente la trombosis en 19 casos (11,44 por ciento). Tiempo medio de maduración de 1 mes fluctuando entre 5 días y 3 meses. Treinta y seis pacientes requirieron nueva FAV y 40 recibieron transplante renal. Duración media de la FAV fue de 4 años fluctuando entre 20 días y 5 años. Discusión: A lo largo del tiempo la técnica descrita por Brescia con trombosis y estenosis. En nuestra serie los casos en que se perdió la FAV, exceptuando aquellos por condiciones propias de los pacientes, se deben a mal manejo de los sitios de punción y poco tiempo de maduración, en todos en los que duró menos de un mes hubo trombosis o estenosis. Si logramos cambiar estos conceptos en nuestro medio optimizaremos la sobrevida de la FAV sin tener que someter a los pacientes a procedimientos seriados, que finalmente conducen al rechazo.
Asunto(s)
Humanos , Masculino , Femenino , Fístula Arteriovenosa/complicaciones , Fístula Arteriovenosa/terapia , Diálisis Renal , Anestésicos Locales/uso terapéutico , Chile , Lidocaína/uso terapéutico , Estudios RetrospectivosRESUMEN
Human placental syncytiotrophoblast is the main barrier for materno-fetal exchange. Analysis of transplacental transport involves the study of ion channels in both the maternal-facing microvillous membrane (MVM) and the fetal-facing basal membrane (BM). Difficulties in having access to intact placenta with conventional electrophysiological methods favour alternative methodologies, such as isolation and reconstitution of membranes in artificial lipid systems. Pre-eclampsia is a major health problem of human pregnancy. The search for altered physiological processes in pre-eclamptic placentae requires the investigation of events at both the microvillous and basal surfaces. The aim of this study was to obtain reliable syncytiotrophoblast plasma membranes from human normal (N) and pre-eclamptic (PE) pregnancies. We describe a protocol which allows for the simultaneous isolation of MVM and BM. The purity of the membranes isolated was evaluated using enzymatic assays, binding studies, Western blotting and immunohistochemistry. Enrichment of alkaline phosphatase activity for MVM was 17 to 21-fold, with 13-16 per cent protein recovery, for both N and PE. Enrichment of adenylate cyclase activity for BM was 9-fold for N, and enrichment of dihydroalprenolol binding to beta-adrenergic receptors was 12-fold for N and 6-fold for PE, with 14 per cent protein recovery for both N and PE. Cross contamination was low and mitochondrial membrane contamination was negligible. We conclude that MVM and BM isolated from placentae of pre-eclamptic women are similar in enrichment and purity to those of healthy women, thus allowing their use in comparative electrophysiological studies.