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1.
Tech Coloproctol ; 27(1): 1-9, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35986804

RESUMEN

Organ preservation strategies, especially watch and wait, after neoadjuvant treatment in locally advanced rectal cancer, have become topics that generate significant interest, for both patients and clinicians. The obvious advantage of these strategies is the avoidance of surgery with its associated risks and functional consequences. Over time, it has become evident that these strategies offer acceptable safety in oncological terms and, in most patients, allows preservation of the rectum without harming patients in terms of distant metastasis or survival. However, there is a small group of patients in whom the tumor returns after an initially diagnosed clinical complete response; patients with local tumor regrowth. The main threat in these patients is not simply local disease, which can be successfully managed in most cases, but the possible effects it may have on distant metastases. The pathophysiology of the phenomenon of local tumor regrowth is not well known and, therefore, strategies to minimize possible impact on survival are not well defined. Our aim is to review key issues in this subgroup that pose a substantial threat to the safety and viability of organ-preserving and watch-and-wait strategies. We also explore possible pathophysiologic explanations and future directions and perspectives that may improve both local and systemic disease control.


Asunto(s)
Terapia Neoadyuvante , Neoplasias del Recto , Humanos , Preservación de Órganos , Neoplasias del Recto/cirugía , Resultado del Tratamiento , Recto/patología , Recurrencia Local de Neoplasia , Quimioradioterapia
2.
Public Health ; 211: 5-13, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35988506

RESUMEN

OBJECTIVES: The SARS-CoV-2 virus has spread worldwide, leading governments to implement mitigation measures. Understanding the reluctance to adhere to non-pharmacological interventions might help promote adherence to these measures. This study aimed to identify factors associated with non-adherence to the first lockdown in Portugal. STUDY DESIGN: Cross-sectional study. METHODS: This study used data from a Portuguese community-based survey entitled 'COVID-19 Barometer: Social Opinion'. Data were collected on risk perception, health status and social experiences using a snowball sampling technique. The event of interest corresponded to participants who reported not staying home during the lockdown period, serving as a proxy for non-adherence to lockdown. Logistic regression was used to identify factors associated with non-adherence to the first lockdown. RESULTS: Responses from 133,601 individual questionnaires that were completed during the first week of the first lockdown in 2020 were analysed. A minority of participants (5.6%) reported non-adherence to lockdown (i.e. leaving home for reasons other than essential situations). Working in the workplace was the factor with the strongest association of non-adherence to the lockdown. Several other factors were also associated with non-adherence to the first lockdown; namely, being a man, being a student, having a low level of education, having a low income, living alone or with a high-infection-risk professional (e.g. doctor, nurse, pharmaceutical, health technician, firefighter, police officer, military, essential services worker), perceiving the risk of getting COVID-19 to be high, not having social support in case of infection, feeling agitated, sad or anxious every day, and considering the preventive measures to be unimportant or inadequate. CONCLUSIONS: Non-adherence to lockdown was associated with socio-economic, trust and perception factors. Future research should investigate the mechanisms underlying these associations to help identify the population groups who are most at risk of non-adherence.


Asunto(s)
COVID-19 , COVID-19/prevención & control , Control de Enfermedades Transmisibles , Estudios Transversales , Humanos , Masculino , Portugal/epidemiología , Cuarentena/métodos , SARS-CoV-2 , Aislamiento Social
3.
Transpl Immunol ; 70: 101519, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34958918

RESUMEN

Immunophenotyping lymphocytes in kidney transplant recipients often raises questions as to whether proportions or absolute counts should be considered, especially for longitudinal assessment. Several studies conclude the pathophysiology of rejection based on proportions of naive and memory B cells. We compared the two analytical methods for B cells sampled from 82 clinically stable, adult kidney transplant recipients. Time post-transplant was analyzed both as a continuous variable and as tertiles (<1.5 years, 1.5-8 years, and > 8 years). B cells were stained for CD38 and IgD and were classified according to mature B cells (Bm) classification. The proportion of cells in the naive Bm2 compartment decreased by more than half in the late versus the early tertile, whereas the percentages of memory early Bm5 tripled and that of memory Bm5 cells doubled. In contrast, we observed a substantial reduction in naive B cell counts, but very stable memory B cell counts. Linear regressions showed that the absolute reduction in the Bm2 cell compartment was independent of age, sex, graft function, immunosuppression scheme, and rejection occurrence. In conclusion, the physiological reservoir of naive cells decreases over time post-transplant in kidney recipients, whereas that of memory B cells remains stable. Peripheral B subset percentages should be interpreted cautiously when analyzing pathophysiological processes.


Asunto(s)
Trasplante de Riñón , Adulto , Linfocitos B , Rechazo de Injerto/diagnóstico , Humanos , Terapia de Inmunosupresión , Inmunosupresores , Receptores de Trasplantes
4.
Arq. bras. med. vet. zootec. (Online) ; 72(4): 1172-1184, July-Aug. 2020. tab, ilus
Artículo en Portugués | LILACS, VETINDEX | ID: biblio-1131494

RESUMEN

Diante da carência de estudos sobre a frequência de dermatopatias que acometem cães por região geográfica no Brasil, o presente estudo objetivou conhecer a frequência das principais doenças cutâneas que afetam cães na região metropolitana de João Pessoa, Paraíba, Brasil. Os dados foram coletados de cães que passaram por atendimento dermatológico no período de setembro de 2014 a dezembro de 2016. Além dos exames clínicos e dermatológicos os cães foram submetidos a exames complementares (citológico, raspado de pele, parasitológico, tricograma, bacteriológico, micológico, histopatológico e molecular). No período do estudo, foram atendidos 1.083 cães, em que 18,65% (202/1.083) apresentavam algum tipo de dermatopatia não tumoral. Dos 202 cães acometidos, 51,49% (104/202) eram machos e 48,51% (98/202), fêmeas. Desses 202 cães, 13 tinham dois diagnósticos, totalizando 215 dermatopatias. Dos cães afetados, 62,87% (127/202) eram de raça definida e 37,13% (75/202), sem raça definida (SRD). As lesões observadas com mais frequência caracterizaram-se por áreas alopécicas, hipotricoicas, maculosas, erosivas e ulcerativas, placoides, eritematosas, assim como comedões, colaretes, seborreia. As dermatopatias parasitárias foram as mais frequentes (35,35%; 76/215), seguidas pelas dermatopatias bacterianas (24,19%; 52/215), dermatopatias alérgicas (20,00%; 43/215), dermatopatias fúngicas (17,21%; 37/215), dermatopatias por outras causas (2,32%; 5/215) e pelas dermatopatias autoimunes (0,93%; 2/215). Os exames físicos e dermatológicos, incluindo anamnese detalhada, histórico clínico apurado, associado a exames complementares, são ferramentas importantes para o diagnóstico das dermatopatias em cães. Presume-se que a frequência de dermatopatias em cães na região de estudo possa ser maior do que a observada.(AU)


Faced with the lack of studies on the frequency of dermatopathies that affect dogs by geographical region in Brazil, the present study aimed to evaluate the frequency of dermatopathies that affect the canine species in the metropolitan region of João Pessoa, Paraíba, Brazil. Data was collected from dogs that underwent dermatological care from September 2014 to December 2016. In addition to the clinical and dermatological examinations, dogs underwent complementary exams, such as cytological, skin scraping, parasitological skin examination, trichogram, bacteriological, mycological, histopathological and/or polymerase chain reaction. During the study period, 1,083 dogs were examined, in which 18.65% (202 /1,083) had some form of non-tumoral dermatopathy. Of the 202 dogs affected, 51.49% (104/202) were males and 48.51% (98/202) females. Of these 202 dogs, thirteen had two diagnoses, totaling 215 dermatopathies. 62.87% (127/202) of the affected dogs were purebred and 37.13% (75/202) were without a defined breed (WDB). The most frequently observed lesions were alopecia, hypotric, macular, erosive and ulcerative, placoid, erythematous areas, as well as comedones, collaretes and seborrhoea. The parasitic dermatopathies were the most frequent (35.35%; 76/215), followed by bacterial dermatopathies (24,19%; 52/215), allergic dermatopathies (20,00%; 43/215), dermatomycosis (17,21%; 37/215), dermatopathies for other causes (2,32%; 5/215) and autoimmune dermatopathies (0.93%; 2/215). Clinical and dermatological examination, including a detailed anamnesis, accurate clinical history and associated complementary exams are important tools for the diagnosis of dermatopathies in dogs. Available literature present some studies with canine dermatopathies frequencies superior to that obtained in the present study; however, the number of animals examined was smaller. In this survey, it was possible to establish the primary and secondary diagnoses in 100.0% of the non-tumoral dermatopathies in dogs, results higher than in previous studies. Probably, the frequency of canine dermatopathies in this region is higher than that observed, thus requiring additional studies with greater sampling.(AU)


Asunto(s)
Animales , Perros , Enfermedades Cutáneas Parasitarias , Enfermedades Cutáneas Bacterianas , Dermatitis Seborreica , Dermatomicosis , Alopecia , Brasil , Reacción en Cadena de la Polimerasa/veterinaria
5.
Tech Coloproctol ; 23(9): 831-842, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31388861

RESUMEN

BACKGROUND: An organ-preserving strategy may be a valid alternative in the treatment of selected patients with rectal cancer after neoadjuvant radiotherapy. Preoperative assessment of the risk for tumor recurrence is a key component of surgical planning. The aim of the present study was to increase the current knowledge on the risk factors for tumor recurrence. METHODS: The present study included individual participant data of published studies on rectal cancer surgery. The literature was reviewed according to according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses of Individual Participant Data checklist (PRISMA-IPD) guidelines. Series of patients, whose data were collected prospectively, having neoadjuvant radiotherapy followed by transanal local excision for rectal cancer were reviewed. Three independent series of univariate/multivariate binary logistic regression models were estimated for the risk of local, systemic and overall recurrence, respectively. RESULTS: We identified 15 studies, and 7 centers provided individual data on 517 patients. The multivariate analysis showed higher local and overall recurrences for ypT3 stage (OR 4.79; 95% CI 2.25-10.16 and OR 6.43 95% CI 3.33-12.42), tumor size after radiotherapy > 10 mm (OR 5.86 95% CI 2.33-14.74 and OR 3.14 95% CI 1.68-5.87), and lack of combined chemotherapy (OR 3.68 95% CI 1.78-7.62 and OR 2.09 95% CI 1.10-3.97), while ypT3 was the only factor correlated with systemic recurrence (OR 5.93). The analysis of survival curves shows that the overall survival is associated with ypT and not with cT. CONCLUSIONS: Local excision should be offered with caution after neoadjuvant chemoradiotherapy to selected patients with rectal cancers, who achieved a good response to neoadjuvant chemoradiotherapy.


Asunto(s)
Terapia Neoadyuvante/estadística & datos numéricos , Recurrencia Local de Neoplasia/etiología , Proctectomía/estadística & datos numéricos , Radioterapia Adyuvante/estadística & datos numéricos , Neoplasias del Recto/terapia , Anciano , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/mortalidad , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Periodo Posoperatorio , Proctectomía/métodos , Neoplasias del Recto/mortalidad , Neoplasias del Recto/patología , Factores de Riesgo , Cirugía Endoscópica Transanal/métodos , Cirugía Endoscópica Transanal/estadística & datos numéricos , Resultado del Tratamiento
6.
Colorectal Dis ; 20 Suppl 1: 12-15, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29878677

RESUMEN

The surgical management of rectal cancer has evolved from a disease without any possibility of cure in the early 1700s where surgical management consisted of the palliative drainage of disease related abscesses to the present day where surgical cure is not only possible but also possible with sphincter or even organ preservation. Prof Habr-Gama's lecture describes the evolution of the surgical management of rectal cancer and the current focus on organ preservation.


Asunto(s)
Tratamientos Conservadores del Órgano/métodos , Mejoramiento de la Calidad , Neoplasias del Recto/terapia , Manejo de la Enfermedad , Historia del Siglo XVIII , Historia del Siglo XIX , Historia del Siglo XX , Humanos , Tratamientos Conservadores del Órgano/historia , Neoplasias del Recto/mortalidad , Neoplasias del Recto/patología , Análisis de Supervivencia , Resultado del Tratamiento
7.
Br J Surg ; 105(2): e192-e203, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29341150

RESUMEN

BACKGROUND: Neoadjuvant chemoradiotherapy (CRT) is one of the preferred initial treatment strategies for locally advanced rectal cancer. Responses are variable, and most patients still require surgery. The aim of this study was to identify molecular mechanisms determining poor response to CRT. METHODS: Global gene expression and pathway enrichment were assessed in pretreatment biopsies from patients with non-metastatic cT2-4 N0-2 rectal cancer within 7 cm of the anal verge. Downstream Akt activation was assessed in an independent set of pretreatment biopsies and in colorectal cancer cell lines using immunohistochemistry and western blot respectively. The radiosensitizing effects of the Akt inhibitor MK2206 were assessed using clonogenic assays and xenografts in immunodeficient mice. RESULTS: A total of 350 differentially expressed genes were identified, of which 123 were upregulated and 199 downregulated in tumours from poor responders. Mitochondrial oxidative phosphorylation (P < 0·001) and phosphatidylinositol signalling pathways (P < 0·050) were identified as significantly enriched pathways among the set of differentially expressed genes. Deregulation of both pathways is known to result in Akt activation, and high immunoexpression of phosphorylated Akt S473 was observed among patients with a poor histological response (tumour regression grade 0-2) to CRT (75 per cent versus 48 per cent in those with a good or complete response; P = 0·016). Akt activation was also confirmed in the radioresistant cell line SW480, and a 50 per cent improvement in sensitivity to CRT was observed in vitro and in vivo when SW480 cells were exposed to the Akt inhibitor MK2206 in combination with radiation and 5-fluorouracil. CONCLUSION: Akt activation is a key event in the response to CRT. Pharmacological inhibition of Akt activation may enhance the effects of CRT. Surgical relevance Organ preservation is an attractive alternative in rectal cancer management following neoadjuvant chemoradiotherapy (CRT) to avoid the morbidity of radical surgery. Molecular steps associated with tumour response to CRT may provide a useful tool for the identification of patients who are candidates for no immediate surgery. In this study, tumours resistant to CRT were more likely to have activation of specific genetic pathways that result in phosphorylated Akt (pAkt) activation. Pretreatment biopsy tissues with high immunoexpression of pAkt were more likely to exhibit a poor histological response to CRT. In addition, the introduction of a pAkt inhibitor to cancer cell lines in vitro and in vivo led to a significant improvement in sensitivity to CRT. Identification of pAkt-activated tumours may thus allow the identification of poor responders to CRT. In addition, the concomitant use of pAkt inhibitors to increase sensitivity to CRT in patients with rectal cancer may constitute an interesting strategy for increasing the chance of a complete response to treatment and organ preservation.


Asunto(s)
Quimioradioterapia/métodos , Terapia Neoadyuvante/métodos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Neoplasias del Recto/metabolismo , Anciano , Animales , Western Blotting , Línea Celular Tumoral , Ensayo de Unidades Formadoras de Colonias , Femenino , Compuestos Heterocíclicos con 3 Anillos/farmacología , Humanos , Inmunohistoquímica , Masculino , Ratones , Ratones Endogámicos BALB C , Persona de Mediana Edad , Neoplasias del Recto/terapia , Transducción de Señal/efectos de los fármacos , Resultado del Tratamiento
8.
J Epidemiol Glob Health ; 8(3-4): 106-109, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30864750

RESUMEN

The relationship between dietary intake and overweight-risk was assessed in 4349 children aged 3-5 years. Eating and sedentary behaviours were assessed by questionnaire. Logistic regressions were used. Children who consumed daily soft-drinks were 1.52 times more likely to be obese, and 72% more likely to be classified as overweight children.


Asunto(s)
Conducta Alimentaria , Sobrepeso , Conducta Sedentaria , Índice de Masa Corporal , Bebidas Gaseosas/efectos adversos , Preescolar , Femenino , Humanos , Masculino , Sobrepeso/diagnóstico , Sobrepeso/epidemiología , Sobrepeso/prevención & control , Sobrepeso/psicología , Portugal/epidemiología , Medición de Riesgo , Factores de Riesgo , Encuestas y Cuestionarios
10.
Biotech Histochem ; 92(8): 584-594, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29172705

RESUMEN

Dysregulation of cellular iron homeostasis in human breast cancer is reflected by the altered expression of regulatory proteins. The expressions of iron-related proteins in the mammary glands of cats and dogs have not been assessed. We evaluated the expressions of ferritin, ferroportin, hepcidin and transferrin receptor 1 in benign and malignant mammary gland lesions in cats and dogs. Iron deposition was detected using Perls' Prussian blue staining. We found no major differences in the expression of iron-related proteins between benign and malignant mammary gland lesions in either cats or dogs; however, these species exhibited accumulation of iron in benign lesions. Our findings provide an explanation for the absence of higher iron requirements by tumor cells in these animals. Further investigation of local iron homeostasis in cats and dogs and differences in their physiology compared to human breast cancer is required.


Asunto(s)
Proteínas Reguladoras del Hierro/metabolismo , Hierro/química , Glándulas Mamarias Animales/metabolismo , Neoplasias Mamarias Animales/química , Animales , Neoplasias de la Mama , Proteínas de Transporte de Catión/metabolismo , Gatos , Perros , Femenino , Ferritinas/metabolismo , Hepcidinas/metabolismo , Inmunohistoquímica , Glándulas Mamarias Animales/química , Glándulas Mamarias Animales/ultraestructura , Neoplasias Mamarias Animales/patología , Estándares de Referencia , Coloración y Etiquetado
12.
Colorectal Dis ; 19(6): O196-O203, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28436197

RESUMEN

AIM: Full-thickness local excision after neoadjuvant chemoradiotherapy (CRT) for patients with rectal cancer and incomplete clinical response has been a treatment strategy for organ preservation. Follow-up of these patients is challenging since anatomic distortion and postoperative changes may be clinically indistinguishable from tumour recurrence. MRI may have a role in detecting recurrence. The aim of this study was to describe the MRI findings during follow-up in patients having local excision following CRT with and without local recurrence. METHOD: The data were collected retrospectively from a single centre. Fifty-three patients with rectal cancer who had full-thickness local excision after neoadjuvant CRT and near-complete response were eligible for the study. Patients with local recurrence were treated by radical salvage surgery. The main outcome was local MRI assessment findings during follow-up. RESULTS: Fifteen patients (five who developed local recurrence and 10 with no evidence of local recurrence) had MR images available for review and were included in the study. High signal intensity and thickening of the rectal wall were present in all patients with recurrent disease within the rectal wall. Overall, 80% of the patients with recurrence showed diffusion restriction. MRI mesorectal fascia status and circumferential resection margin showed agreement in all cases. A low signal intensity scar was seen in all patients without recurrent disease. CONCLUSION: MRI shows high signal intensity and thickening of the rectal wall in recurrent disease in comparison to a low signal intensity fibrotic scar in non-recurrent disease. These findings may be useful in surveillance of these patients.


Asunto(s)
Quimioradioterapia Adyuvante/métodos , Imagen por Resonancia Magnética , Recurrencia Local de Neoplasia/diagnóstico por imagen , Neoplasias del Recto/diagnóstico por imagen , Microcirugía Endoscópica Transanal/métodos , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante/métodos , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/cirugía , Estadificación de Neoplasias , Periodo Posoperatorio , Neoplasias del Recto/patología , Neoplasias del Recto/terapia , Recto/diagnóstico por imagen , Recto/cirugía , Estudios Retrospectivos , Terapia Recuperativa , Resultado del Tratamiento
13.
Int J STD AIDS ; 28(13): 1299-1304, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28399709

RESUMEN

Syphilis is a systemic and sexually transmitted infection caused by Treponema pallidum ssp. pallidum. This spirochete causes different clinical and subclinical stages depending on the duration of infection and immune status of the host. Several tests have been developed for diagnosis, and are classified into direct and indirect methods. The first one includes dark field microscopy, direct fluorescent antibody test in fluids or tissue, and molecular biology techniques. In the indirect method (serologic), the routine tests are used, and are divided in two categories: non-treponemal and treponemal ones. The objective of this work was to identify T. pallidum ssp. pallidum in paraffin-embedded skin biopsies positive by immunohistochemistry, using conventional polymerase chain reaction (PCR) and quantitative real time PCR (qPCR). We included a sample of 17 paraffin-embedded biopsies. DNA was extracted and processed by conventional PCR and real-time PCR with a TaqMan® probe to identify the polA gene. Using PCR, 11 tested positive (64.7%) and 6 (35.3%) were negative. With qPCR and TaqMan® probe, 100% of samples tested positive. The minimum number of spirochetes detected in each sample was 2. With this work, we can conclude that qPCR is a fast and very accurate method for diagnosis of syphilis in tissue specimens.


Asunto(s)
Genes pol/genética , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Piel/microbiología , Sífilis Cutánea/diagnóstico , Treponema pallidum/genética , Treponema pallidum/aislamiento & purificación , Biopsia , ADN Bacteriano/análisis , ADN Bacteriano/genética , Humanos , Inmunohistoquímica , Adhesión en Parafina , Piel/patología , Serodiagnóstico de la Sífilis , Sífilis Cutánea/inmunología , Polimerasa Taq , Treponema pallidum/inmunología
14.
Acta Physiol (Oxf) ; 219(4): 803-813, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27228549

RESUMEN

AIM: Exercise training has been suggested as a non-pharmacological approach to prevent skeletal muscle wasting and improve muscle function in cancer cachexia. However, little is known about the molecular mechanisms underlying such beneficial effect. In this study, we aimed to, firstly, examine the contribution of TWEAK signalling to cancer-induced skeletal muscle wasting and, secondly, evaluate whether long-term exercise alters TWEAK signalling and prevents muscle wasting. METHODS: Female Sprague-Dawley rats were randomly assigned to control and exercise groups. Fifteen animals from each group were exposed to N-Methyl-N-nitrosourea carcinogen. Animals in exercise groups were submitted to moderate treadmill exercise for 35 weeks. After the experimental period, animals were killed and gastrocnemius muscles were harvested for morphological and biochemical analysis. RESULTS: We verified that exercise training prevented tumour-induced TWEAK/NF-κB signalling in skeletal muscle with a beneficial impact in fibre cross-sectional area and metabolism. Indeed, 35 weeks of exercise training promoted the upregulation of PGC-1α and oxidative phosphorylation complexes. This exercise-induced muscle remodelling in tumour-bearing animals was associated with less malignant mammary lesions. CONCLUSION: Data support the benefits of an active lifestyle for the prevention of muscle wasting secondary to breast cancer, highlighting TWEAK/NF- κB signalling as a potential therapeutic target for the preservation of muscle mass.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/biosíntesis , Caquexia/metabolismo , Neoplasias Mamarias Experimentales/complicaciones , Proteínas de la Membrana/biosíntesis , Condicionamiento Físico Animal/métodos , Transducción de Señal , Factores de Necrosis Tumoral/biosíntesis , Animales , Caquexia/etiología , Citocina TWEAK , Modelos Animales de Enfermedad , Femenino , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Atrofia Muscular/etiología , Atrofia Muscular/metabolismo , FN-kappa B/metabolismo , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Transducción de Señal/fisiología
15.
Braz. j. biol ; 76(3): 718-725, graf
Artículo en Inglés | LILACS | ID: lil-785043

RESUMEN

Abstract This study aimed to model the habitat suitability for an invasive clam Corbicula fluminea in a coastal shallow lagoon in the southern Neotropical region (–30.22, –50.55). The lagoon (19km2, maximum deep 2.5m) was sampled with an Ekman dredge in an orthogonal matrix comprising 84 points. At each sampling point, were obtained environmental descriptors as depth, organic matter content (OMC), average granulometry (Avgran), and the percentage of sand (Pcsand). Prediction performance of Generalized Linear Models (GLM), Generalized Additive Models (GAM) and Boosted Regression Tree (BRT) were compared. Also, niche overlapping with other native clam species (Castalia martensi, Neocorbicula limosa and Anodontites trapesialis) was examined. A BRT model with 1400 trees was selected as the best model, with cross-validated correlation of 0.82. The relative contributions of predictors were Pcsand-42.6%, OMC-35.8%, Avgran-10.9% and Depth-10.8%. Were identified that C. fluminea occur mainly in sandy sediments with few organic matter, in shallow areas nor by the shore. The PCA showed a wide niche overlap with the native clam species C. martensi, N. limosa and A. trapesialis.


Resumo O objetivo de deste estudo foi modelar a adequabilidade de habitat do bivalve invasor Corbicula fluminea em uma lagoa costeira na região Neotropical (–30.22, –50.55). A lagoa (19km2, 2,5 m de profundidade máxima) foi amostrada com uma draga Ekman em uma matriz ortogonal compreendendo 84 pontos. Em cada ponto de amostragem foram obtidos descritores ambientais como a profundidade, teor de matéria orgânica (OMC), granulometria média (Avgran), e a percentagem de areia (Pcsand). O poder preditivo dos métodos Modelos Lineares Generalizados (GLM), Modelos Aditivos Generalizados (GAM) e Boosted Regression Trees (BRT) foram comparados. Além disso, a sobreposição de nicho com espécies de moluscos nativos (Castalia martensi, Neocorbicula limosa e Anodontites trapesialis) foi examinada. Um modelo BRT com 1.400 árvores foi selecionado como o melhor modelo, com correlação da validação cruzada de 0,82. As contribuições relativas dos preditores foram Pcsand-42,6%, OMC-35,8%, Avgran-10,9% e profundidade-10,8%. Foi demonstrado que C. fluminea está associada a sedimentos arenosos com pouca matéria orgânica, em áreas rasas próximo às margens. A PCA mostrou uma ampla sobreposição de nicho com as espécies de moluscos nativos C. martensi, N. limosa e A. trapesialis.


Asunto(s)
Animales , Ecosistema , Corbicula , Especies Introducidas/estadística & datos numéricos , Brasil , Dinámica Poblacional , Monitoreo del Ambiente , Densidad de Población , Modelos Teóricos
16.
Biomed Pharmacother ; 81: 273-280, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27261604

RESUMEN

BACKGROUND: Breast cancer remains a leading cause of death by cancer worldwide. It is commonly accepted that angiogenesis and the expression of angiogenic factors such as vascular endothelial growth factor-A (VEGF-A) is associated with the increased risk of metastasis and poor patient outcome. OBJECTIVE: This work aimed to evaluate the effects of long-term exercise training on the growth and vascularization of mammary tumors in a rat model. MATERIALS AND METHODS: Fifty female Sprague-Dawley rats were divided into four groups: two N-methyl-N-nitrosourea (MNU)-exposed groups (exercised and sedentary) and two control groups (exercised and sedentary). MNU was administered once, intraperitoneally at 7 weeks-old. Animals were then exercised on a treadmill for 35 weeks. Mammary tumors were evaluated using thermography, ultrasonography [Power Doppler (PDI), B Flow and contrast-enhanced ultrasound (CEUS)], and immunohistochemistry (VEGF-A). RESULTS: Both, MNU sedentary and exercised groups showed 100% of tumor incidence, but exercised animals showed less tumors with an increased latency period. Exercise training also enhanced VEGF-A immunoexpression and vascularization (microvessel density, MVD) (p<0.05), and reduced histological aggressiveness. Ultrasound and thermal imaging analysis confirmed the enhanced vascularization of tumors on exercised animals. CONCLUSION: Long-term exercise training increased VEGF-A expression, leading to enhanced tumor vascularization and reduced tumor burden, multiplicity and histological aggressiveness.


Asunto(s)
Neoplasias Mamarias Experimentales/irrigación sanguínea , Neoplasias Mamarias Experimentales/fisiopatología , Neovascularización Patológica/fisiopatología , Condicionamiento Físico Animal , Animales , Femenino , Inmunohistoquímica , Neoplasias Mamarias Experimentales/diagnóstico por imagen , Neoplasias Mamarias Experimentales/patología , Tamaño de los Órganos , Ratas Sprague-Dawley , Termografía , Factores de Tiempo , Ultrasonografía , Factor A de Crecimiento Endotelial Vascular/metabolismo
17.
Braz J Biol ; 76(3): 718-25, 2016 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-27097092

RESUMEN

This study aimed to model the habitat suitability for an invasive clam Corbicula fluminea in a coastal shallow lagoon in the southern Neotropical region (-30.22, -50.55). The lagoon (19km2, maximum deep 2.5m) was sampled with an Ekman dredge in an orthogonal matrix comprising 84 points. At each sampling point, were obtained environmental descriptors as depth, organic matter content (OMC), average granulometry (Avgran), and the percentage of sand (Pcsand). Prediction performance of Generalized Linear Models (GLM), Generalized Additive Models (GAM) and Boosted Regression Tree (BRT) were compared. Also, niche overlapping with other native clam species (Castalia martensi, Neocorbicula limosa and Anodontites trapesialis) was examined. A BRT model with 1400 trees was selected as the best model, with cross-validated correlation of 0.82. The relative contributions of predictors were Pcsand-42.6%, OMC-35.8%, Avgran-10.9% and Depth-10.8%. Were identified that C. fluminea occur mainly in sandy sediments with few organic matter, in shallow areas nor by the shore. The PCA showed a wide niche overlap with the native clam species C. martensi, N. limosa and A. trapesialis.


Asunto(s)
Corbicula , Ecosistema , Especies Introducidas/estadística & datos numéricos , Animales , Brasil , Monitoreo del Ambiente , Modelos Teóricos , Densidad de Población , Dinámica Poblacional
19.
Pediatr Obes ; 11(3): 202-9, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26178147

RESUMEN

BACKGROUND: Maternal smoking during pregnancy has been associated with increased risk of childhood overweight/obesity defined by body mass index (BMI). We examined its association with a range of adiposity measures and cardiovascular indicators in children aged 3-10 years. METHODS: We used data from a cross-sectional study of schoolchildren across mainland Portuguese districts (2009-2010). We applied quantile regressions to examine maternal smoking associations with adiposity (n = 17 286), blood pressure (BP) and resting pulse rate (RPR) (n ≈ 2500) measures across the age range, adjusting for prenatal and early life factors. RESULTS: Maternal smoking during pregnancy was associated with increases in offspring adiposity levels. The difference in median BMI between children of smokers and non-smokers was 0.39 kg m(-2) (95% confidence interval: 0.25, 0.53) in boys and 0.46 kg m(-2) (0.31, 0.62) in girls; 0.55 cm (0.24, 0.87) and 0.82 cm (0.45, 1.19), respectively, in median waist circumference; and 0.94 mm (0.49, 1.40) and 1.47 mm (0.87, 2.07) in median sum of (triceps, subscapular, suprailiac) skin-folds. The associations appeared to be stronger with increasing age. The differences in the 90th centile tended to be greater than those in median. There was no consistent association of maternal smoking with BP and RPR. CONCLUSIONS: Children whose mother smoked during pregnancy had higher adiposity levels than children of non-smokers, across several measures, particularly among older children. Although there was no consistent association with cardiovascular indicators, maternal smoking association with childhood obesity may have implications for cardiovascular risk factors over the life course.


Asunto(s)
Adiposidad/fisiología , Presión Sanguínea , Efectos Tardíos de la Exposición Prenatal , Fumar/efectos adversos , Índice de Masa Corporal , Enfermedades Cardiovasculares/etiología , Niño , Preescolar , Estudios Transversales , Femenino , Humanos , Masculino , Madres , Sobrepeso/complicaciones , Obesidad Infantil/complicaciones , Obesidad Infantil/fisiopatología , Embarazo , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Factores de Riesgo , Grosor de los Pliegues Cutáneos , Circunferencia de la Cintura
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