RESUMEN
Detecting changes in the phenological responses of herbaceous species as a function of predicted climate change is important for forecasting future scenarios for the functioning of dry tropical forests, especially when predicting an increase in the frequency and intensity of extreme droughts. Because of the sensitivity of plants to water availability, our study hypothesizes that if years become drier or wetter, herbaceous plants will synchronously change the onset, duration, and intensity of their vegetative phenophases. We used a historical series of 60 years of precipitation observations for the Caatinga vegetation to define daily average of precipitation for rainy (Twet), median (Tcontrol), and dry (Tdry) years. We simulated past average daily rainfall (Twet, Tcontrol, and Tdry) while growing two herbaceous perennials and two herbaceous annuals. We monitored plant growth and measured the activity (absence or presence) and intensity of vegetative phenophases. We used circular statistical analysis to assess differences between treatments. Our results revealed that leaf production was seasonal but relatively uniform for perennial species and highly seasonal (wet season) for annual species. Simulated dry years induced lower leaf emergence concentrated over a few months in annual species, but this effect was more strongly significant in one of the two perennial species. Both annual and perennial species can experience delayed and less intense leaf abscission during the rainy season in years with below-average precipitation. In contrast, large voluminous rains in years with above-average precipitation can accelerate and intensify the process of leaf renewal. If future precipitation reductions occur, the changes in phenological response indicate that the cover of annual and perennial herbaceous species in this study will likely decrease, altering the landscape and functioning of dry tropical forests. However, the potential trade-offs observed may help populations of these species to persist during years of severe drought in the Caatinga.
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Bosques , Lluvia , Estaciones del Año , Brasil , Cambio Climático , Hojas de la Planta/fisiología , Hojas de la Planta/crecimiento & desarrollo , SequíasRESUMEN
PURPOSE: Studying breast and cervical cancers in space and time and verifying divergences of different territorially established socioeconomic profiles. METHODS: Ecological study using spatial scanning (with socioeconomic characterization), space-time, and spatial variation of temporal trends, in order to identify significant clusters of high- and low-risk or temporal trends, of deaths from breast cancer and cervical cancer, in the city of São Paulo, Brazil, during 2000-2016. RESULTS: High-risk spatial clusters were identified in the central areas, and low-risk clusters were identified in the peripheral areas, which were associated with better and worse socioeconomic conditions, respectively. As for cervical cancer, the pattern was the opposite. High-risk space-time clusters occurred in the early years of the study, whereas low-risk clusters occurred in the most recent years. For breast cancer, the central areas showed a temporal trend of decreasing mortality and the peripheral areas showed an increasing trend. While for cervical cancer, in general, the temporal trend was for the identified clusters to fall. CONCLUSIONS: It is expected that this study will provide insights for the formulation of public policies to implement prevention and control measures, in order to reduce mortality and inequalities related to breast and cervical cancers.
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Neoplasias de la Mama , Neoplasias del Cuello Uterino , Femenino , Humanos , Brasil/epidemiología , RegistrosRESUMEN
A placenta is defined as structural approximation of maternal and foetal tissues to perform physiological exchange. Associated processes of differentiation and the establishment of its cells take place within the extracellular matrix (ECM) that provides a rich environment of collagens, fibronectins, cytokines and other components. Placental ECM is promising for tissue regeneration purposes, because it has immune tolerance capacities that may cause only minimal rejections of transplants with immunological differences between donor and recipient. However, specific characteristics of ECM during evolution of the structurally very diverse mammalian placenta are not yet revealed. We here address the major aspects of placental types, that is non-invasive (epitheliochorial), medium (endotheliochorial)-to-high (haemochorial) invasive nature of the interhemal barrier between the foetal and maternal blood system as well as their main components of ECM with special reference to species that are commonly used as animal models for human placentation and in the potential applications for regenerative medicine.
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Matriz Extracelular/fisiología , Mamíferos/fisiología , Placenta/anatomía & histología , Placentación/fisiología , Medicina Regenerativa , Animales , Femenino , Humanos , EmbarazoRESUMEN
Meta-analytical evidence suggests that brain-derived neurotrophic factor (BDNF) is altered in various psychiatric disorders. However, meta-analyses may be hampered by the heterogeneity of BDNF assays, lack of BDNF standard values and heterogeneity among the populations included in the studies. To address these issues, our study aimed to test, in a 'true-to-life' setting, the hypothesis that the serum BDNF level is nonspecifically reduced in acute severe mental illness (SMI) patients and increases during inpatient treatment. Consecutive samples of 236 inpatients with SMI and 100 healthy controls were recruited. SMI includes schizophrenia and severe mood disorders, and is characterized in the sample by the presence of at least 2 years of psychiatric treatment and disability. Generalized estimating equations were used to analyze BDNF serum levels at admission and upon discharge controlled by confounding factors. BDNF levels increased significantly between admission and discharge in SMI patients. BDNF levels showed significant reductions compared with controls both at admission and upon discharge. In addition, BDNF levels showed no difference among SMI patient diagnostic subgroups (unipolar depression, bipolar depression, schizophrenia and manic episode). The increase but non-restoration of BDNF levels, even with the general acute improvement of clinical scores, may reflect the progression of the disorder characteristically seen in these patients. BDNF levels could be considered as a marker for the presence of a nonspecific psychiatric disorder and possibly a transdiagnostic and nonspecific marker of disease activity.
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Factor Neurotrófico Derivado del Encéfalo/sangre , Hospitalización , Trastornos Mentales/sangre , Trastornos Mentales/terapia , Adulto , Trastorno Bipolar/sangre , Trastorno Bipolar/diagnóstico , Trastorno Bipolar/psicología , Trastorno Bipolar/terapia , Brasil , Trastorno Depresivo Mayor/sangre , Trastorno Depresivo Mayor/diagnóstico , Trastorno Depresivo Mayor/psicología , Trastorno Depresivo Mayor/terapia , Femenino , Estudios de Seguimiento , Hospitales Generales , Humanos , Masculino , Trastornos Mentales/diagnóstico , Trastornos Mentales/psicología , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Servicio de Psiquiatría en Hospital , Esquizofrenia/sangre , Esquizofrenia/diagnóstico , Esquizofrenia/terapia , Psicología del EsquizofrénicoRESUMEN
BACKGROUND: Liver transplantation is indicated at the end stage of chronic liver failure, and severity of disease will determine the precocity of this happening. At this stage, the presence of chronic dyspnea is one of several manifestations of progression of the disease, which leads the patient to inactivity. A rehabilitation program can positively influence the evolution of liver transplant recipients. The objective of this study was to establish an association between the perception of dyspnea and the severity of liver disease in patients at a single center of a Brazilian liver pre-transplantation clinic. METHODS: Measurements were performed at a liver pre-transplantation clinic. The severity of liver disease was assessed with the use of the Model for End-Stage Liver Disease (MELD) score, and dyspnea was assessed with the use of a modified Medical Research Council scale of dyspnea (mMRC). RESULTS: Men had a higher prevalence of viral hepatitis. Dyspnea was reported only during intense exercise. Duration of disease and MELD score showed medians of 49 months and 20, respectively. CONCLUSIONS: We found no correlation between mMRC and the MELD score. In addition, no correlation was found between duration of disease and MELD score or mMRC.
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Disnea/epidemiología , Cirrosis Hepática/epidemiología , Trasplante de Hígado , Adulto , Brasil/epidemiología , Enfermedad Hepática en Estado Terminal , Femenino , Hepatitis Autoinmune/complicaciones , Hepatitis Viral Humana/complicaciones , Humanos , Cirrosis Hepática/etiología , Cirrosis Hepática/cirugía , Cirrosis Hepática Alcohólica/epidemiología , Cirrosis Hepática Alcohólica/cirugía , Masculino , Persona de Mediana Edad , Proyectos Piloto , Periodo Preoperatorio , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Listas de EsperaRESUMEN
OBJECTIVE: Frontiers between pediatric bipolar disorder (PBD) and attention-deficit/hyperactivity disorder (ADHD) are not well defined. Few studies have addressed potentially different neurobiological factors between the two disorders. Brain-derived neurotrophic factor (BDNF) has been increasingly recognized for its etiologic and prognostic role in adult bipolar disorder (BD) studies. This study aimed to examine the BDNF gene polymorphism and potential alterations in BDNF serum levels in the pediatric ADHD patients with or without comorbid BD illness. METHOD: We assessed the non-synonymous single-nucleotide polymorphism in the BDNF gene (rs6265/Val66Met) and its serum levels in children and adolescents with BD comorbid with ADHD (BD + ADHD) and ADHD alone. Children and adolescents were assessed for psychiatric diagnoses using the Kiddie-Sads-Present and Lifetime Version (K-SADS-PL). RESULTS: Using Analysis of covariance (ancova) we detected a significant group effect (patients with BD + ADHD had higher serum levels than those with ADHD - F80,3 = 8.73, P = 0.005). CONCLUSION: Although the Val66Met polymorphism at the BDNF gene does not seem to play a significant role in children and adolescents with BD or ADHD, BDNF serum levels deserve further attention in future research on neurobiological aspects of BD and ADHD.
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Trastorno por Déficit de Atención con Hiperactividad/genética , Trastorno Bipolar/genética , Factor Neurotrófico Derivado del Encéfalo/genética , Polimorfismo de Nucleótido Simple , Adolescente , Factor Neurotrófico Derivado del Encéfalo/sangre , Niño , Preescolar , Femenino , Humanos , Masculino , Escalas de Valoración PsiquiátricaRESUMEN
OBJECTIVE: The impact of childhood trauma (CT) on brain-derived neurotrophic factor (BDNF) and cytokines levels remains unclear. We investigated the association between CT and changes in BDNF and cytokines plasma levels in children. METHOD: We recruited 36 children with trauma (CT+) and 26 children without trauma (CT-). The presence of CT was based on a clinical interview and by Criteria A of DSM-IV criteria for PTSD. Blood samples were drawn from all children to assess BDNF and cytokines. ancova was performed with psychiatric symptoms and BMI as covariates to evaluate group differences in plasma levels. RESULTS: CT+ showed increased levels of BDNF and TNF-α after excluding children with history of inflammatory disease (P<0.05) when compared with those CT-. IL-12p70, IL-6, IL-8, IL-10, and IL-1ß levels were not statistically different between groups. CONCLUSION: CT+ showed increased BDNF and proinflammatory cytokines levels. The increase in BDNF levels may be an attempt to neutralize the negative effects of CT, while an increase in TNF-a levels be associated with a proinflammatory state after CT. How these changes associated with trauma relate to other biological changes and illness trajectory later in life remain to be further studied.
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Factor Neurotrófico Derivado del Encéfalo/sangre , Maltrato a los Niños/psicología , Citocinas/sangre , Trastornos por Estrés Postraumático , Factor de Necrosis Tumoral alfa/sangre , Biomarcadores/sangre , Niño , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Femenino , Humanos , Inflamación/sangre , Masculino , Psicopatología , Trastornos por Estrés Postraumático/sangre , Trastornos por Estrés Postraumático/diagnóstico , Trastornos por Estrés Postraumático/etiología , Trastornos por Estrés Postraumático/fisiopatologíaRESUMEN
BACKGROUND: Helicobacter pylori (H. pylori) is the main risk factor for the development of chronic gastritis, gastric ulcer, and gastric cancer. In H. pylori-infected individuals, the clinical result is dependent on various factors, among which are bacterial components, the immune response, and environmental influence. AIMS: To compare IFN-γ expression with the H. pylori vacA and cagA genotypes in patients with chronic gastritis and patients with gastric cancer. METHODS: Ninety-five patients diagnosed with chronic gastritis and 20 with gastric cancer were included in the study. Three gastric biopsies were taken; one was used for the molecular detection and genotyping of H. pylori; another was fixed in absolute alcohol and histologic sections were made for determining IFN-γ expression through immunohistochemistry. RESULTS: No differences were found in the cells that expressed IFN-γ between the patients with chronic gastritis (median percentage of positive cells: 82.6% in patients without H. pylori and 82% in infected persons) and those with gastric cancer (70.5% in H. pylori-negative patients and 78.5% in infected persons). IFN-γ expression was 69% in chronic gastritis patients infected with H. pylori vacAs2m2/cagAâ» it was 86.5% in patients infected with H. pylori vacAs1m2/cagAâ», 86.5% in vacAs1m1/cagAâ», and 82% in vacAs1m1/cagAâº. Similar data were found in the patients with gastric cancer. CONCLUSIONS: IFN-γ expression varied depending on the H. pylori vacA and cagA genotype, but not in accordance with the presence of chronic gastritis or gastric cancer.
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Gastritis/metabolismo , Gastritis/microbiología , Helicobacter pylori/genética , Interferón gamma/biosíntesis , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/microbiología , Adulto , Anciano , Enfermedad Crónica , Femenino , Genes Bacterianos/genética , Variación Genética , Genotipo , Infecciones por Helicobacter/microbiología , Humanos , Masculino , Persona de Mediana EdadRESUMEN
In this study, we examined the distribution of genotype and allele frequencies of the C677T and A1298C polymorphisms in the methylenetetrahydrofolate-reductase gene (MTHFR) in two ethnic groups in the State of Guerrero, Mexico, which were compared with those of the Mestizo population of the region. A comparative study was conducted on 455 women from two ethnic groups and a group of Mestizo women of the State of Guerrero, Mexico: 135 Nahuas, 124 Mixtecas, and 196 Mestizas. Genotyping of both polymorphisms were performed by using polymerase chain reaction-restriction fragment length polymorphism methods. We found that the 677TT genotype was more frequent in Nahua and Mixteca women compared to Mestiza women (P = 0.008), and the most prevalent genotype in both ethnic groups was the 1298AA genotype (P < 0.001). We also compared the 677T allele frequency obtained from the groups studied with the frequencies reported in other ethnic groups of Mexico (Huichol, Tarahumara, and Purepecha). There were significant differences between the three ethnic groups compared to Nahuas (Huicholes, P = 0.004; Tarahumaras, P < 0.001; Purepechas, P = 0.042). Our results indicated significant differences in the frequencies of the C677T and A1298C polymorphisms between the two ethnic groups and the Mestizo population of the State of Guerrero. In addition, we found strong differences with other ethnic groups in Mexico. These results could be useful for future studies investigating diseases related to folate metabolism, and could help the government to design specific nutrition programs for different ethnic groups.
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Etnicidad/genética , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Polimorfismo Genético , Femenino , Frecuencia de los Genes , Genotipo , Humanos , MéxicoRESUMEN
BACKGROUND: Cyclin-A and cyclin-E are regulators of G1-S phase of normal cell cycle. Integration of human papilloma virus high-risk (HR-HPV) could alter this mechanism, and its overexpression has been associated with poor prognosis in cervical cancer. AIM: To determine the expression of cyclin-A and cyclin-E, types of HR-HPV and physical state of DNA in cytologies with the diagnosis of low-grade squamous intraepithelial lesion (LSIL). MATERIALS AND METHODS: 115 cytological specimens in liquid base (liquid-PREP(™)) were analyzed. 25 specimens were with no signs of SIL (NSIL) and without HPV; 30 with NSIL with low-risk HPV (LR-HPV); 30 with NSIL with HR-HPV; and 30 with both LSIL and HR-HPV. The expression of cyclins was evaluated by immunocytochemistry; and the detection of viral DNA was done by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLPs) for genotyping or sequencing of HPV. The physical state of HPV was evaluated by in situ hybridization with amplification with tyramide. RESULTS: In the cytologies NSIL with LR-HPV, the expression of cyclin-A and cyclin-E was found respectively in 23.3% and 33.3% of the specimens. Among the specimens of NSIL with HR-HPV, 33.3% expressed cyclin-A and 40% cyclin-E, while 100% of the LSILs expressed the 2 cyclins. On the other hand, 100% of the samples NSIL with LR-HPV presented an episomal pattern. Of the specimens of NSIL with HR-HPV, 56.6% exhibited an episomal pattern, 23.3% integrated and 20%, mixed. Among the LSILs, 90% were mixed and 10% integrated. CONCLUSIONS: The cyclins A and E are present in the LSILs that occur predominantly in mixed state in the presence of HR-HPV.
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Variants in the C-reactive protein (CRP) gene have been found to be associated with various phenotypic traits. We evaluated the effect of four SNPs in the CRP gene on serum levels of protein and body mass index (BMI) in 150 unrelated Mexican subjects from 18 to 25 years old, without hypertension, non-overweight, and without inflammatory diseases, non-smoking and non-consumers of alcohol. Subjects were measured for BMI, waist circumference, blood pressure, and serum glucose and triglycerides. The identification of SNPs was performed by PCR-RFLP. Three of the four SNPs were associated with variation in serum levels of CRP, increased in TT (rs1130864) and GG (rs2794521) genotypes, and decreased in the AA genotype of rs1205. The TT genotype was associated with a significant increase in BMI (ß = 1.1 kg/m², P = 0.04). Two haplotypes were significantly associated with increased serum levels of CRP, but not with BMI. We conclude that variation in the CRP gene affects serum protein levels.
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Índice de Masa Corporal , Proteína C-Reactiva/genética , Estudios de Asociación Genética , Salud , Polimorfismo de Nucleótido Simple/genética , Adolescente , Adulto , Alelos , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/genética , Demografía , Femenino , Frecuencia de los Genes/genética , Predisposición Genética a la Enfermedad , Haplotipos/genética , Humanos , Masculino , México , Factores de Riesgo , Adulto JovenRESUMEN
The purpose of the present study was to evaluate the effect of treatment with oxamniquine on the portal pressure of mice infected with Schistosoma mansoni. The animals were infected with 30 cercariae and portal pressure was measured with a polygraph at 70 (acute phase) and 160 (chronic phase) days after infection. On days 70 and 160 two other groups of infected mice were treated with 400 mg/kg of oxamniquine and portal pressure was measured 90 days later (160 and 250 days after infection). A group of uninfected mice was used as control. The measured portal pressures, in mmHg, were: matched uninfected control mice 8.7+/-2.1 and acute phase group, measured at day 70, 13.4+/-3.5. Matched uninfected control 7.5+/-0.6 and chronic phase group, measured at day 160 post-infection, 11.6+/-1.5. Matched uninfected mice 6.9+/-0.9 and chronic phase group, measured at day 250, 10.4+/-1.8. Oxamniquine-treated at day 70 and measured at day 160 7.9+/-0.4; oxamniquine-treated at day 160 and measured at day 250, 7.6+/-1.7. The infection of mice with 30 cercariae of S. mansoni induced portal hypertension, both during the acute and chronic phases and treatment with oxamniquine caused portal pressure to return to normal levels.
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Hipertensión Portal/tratamiento farmacológico , Oxamniquina/uso terapéutico , Esquistosomiasis mansoni/tratamiento farmacológico , Esquistosomicidas/uso terapéutico , Animales , Hipertensión Portal/etiología , Masculino , Ratones , Esquistosomiasis mansoni/complicacionesRESUMEN
Outbred male albino mice normal or infected with 30 cercariae of Schistosoma mansoni (LE strain) were submitted to 65% hepatectomy during the acute (70 days) and chronic phase (160 days) phases of the disease. A group of the infected animals was treated with 400 mg/kg of oxamniquine during the acute phase before hepatectomy. Non-infected, infected and treated but not hepatectomized animals were kept as controls. Hepatic regeneration was evaluated by incorporation of tritiated thymidine, intraperitoneally injected into non-hepatectomized and hepatectomized animals, 24 hours after surgery. The results showed that removal of 65% of the hepatic parenchyma, during the acute phase, led to a statistically significant increase of thymidine incorporation, when compared with the uninfected hepatectomized controls. This phenomenon was not observed at the chronic phase. Treatment with oxamniquine administered during the acute phase led to a decrease in thymidine incorporation rate 160 days after infection (90 days after treatment) and 24 hours after hepatectomy. The data suggest that infection with S. mansoni represents a considerable stimulus for the regenerative capacity of the liver during the acute, but not the chronic phase of disease.
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Hepatectomía , Regeneración Hepática , Oxamniquina/uso terapéutico , Schistosoma mansoni , Esquistosomiasis mansoni/tratamiento farmacológico , Esquistosomicidas/uso terapéutico , Enfermedad Aguda , Animales , Enfermedad Crónica , Masculino , Ratones , Esquistosomiasis mansoni/inducido químicamente , Timidina/metabolismoRESUMEN
Outbred male albino mice normal or infected with 30 cercariae of Schistosoma mansoni (LE strain) were submitted to 65 percent hepatectomy during the acute (70 days) and chronic phase (160 days) phases of the disease. A group of the infected animals was treated with 400 mg/kg of oxamniquine during the acute phase before hepatectomy. Non-infected, infected and treated but not hepatectomized animals were kept as controls. Hepatic regeneration was evaluated by incorporation of tritiated thymidine, intraperitoneally injected into non-hepatectomized and hepatectomized animals, 24 hours after surgery. The results showed that removal of 65 percent of the hepatic parenchyma, during the acute phase, led to a statistically significant increase of thymidine incorporation, when compared with the uninfected hepatectomized controls. This phenomenon was not observed at the chronic phase. Treatment with oxamniquine administered during the acute phase led to a decrease in thymidine incorporation rate 160 days after infection (90 days after treatment) and 24 hours after hepatectomy. The data suggest that infection with S. mansoni represents a considerable stimulus for the regenerative capacity of the liver during the acute, but not the chronic phase of disease