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1.
Aquat Toxicol ; 185: 95-104, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28208108

RESUMO

Many man-made chemical compounds are recognized as endocrine disruptors and once released into the environment are likely to spread and bioaccumulate in wild species. Due to their lipophilic nature, these substances pass through the cell membrane or bind to specific receptors activating physiological responses that in the long run can cause reproductive impairment, physiological disorders, including the occurrence of metabolic syndromes. One significant source of contamination is represented by the consumption of polluted food. As a consequence, different environmental pollutants, with similar or different modes of action, can accumulate in organisms and biomagnify along the food web, finally targeting humans. The aim of this study was to analyze, under controlled conditions, the effects induced by the consumption of contaminated diets, focusing on the effects exerted at hepatic level. Juvenile seabream were fed for 21days a diet enriched with different combinations of pollutants, nonylphenol (NP), tert-octylphenol (t-OP) and bisphenol A (BPA). The different diets containing 5mg/kg bw of each contaminant, were formulated as follows: NP+tOP, BPA+NP, BPA+tOP and NP+BPA+tOP (NBO). EDCs, at the doses administered, showed low biomagnification factor (BMF), suggesting that these pollutants hardly accumulate in muscles. The results obtained at hepatic level pinpointed the steatotic effect of all the administered diets, associated to a modulation of the expression of genes involved in lipid metabolism (ppars, fas, lpl, and hsl). Results were compared to those obtained in previous studies in which fish were fed single pollutants evidencing that the administration of mixture of contaminants exerts a milder lipogenic effect, highlighting the contrasting/antagonistic interaction establishing among chemicals. Noteworthy was the setup of a new chromatographic method to detect the presence of the selected chemical in fish muscle and the application of Fourier Transform Infrared (FT-IR) analysis to evaluate pollutant-induced changes in the liver macromolecular building.


Assuntos
Dieta , Disruptores Endócrinos/toxicidade , Metabolismo dos Lipídeos/efeitos dos fármacos , Dourada/metabolismo , Ração Animal , Animais , Compostos Benzidrílicos/toxicidade , Biomarcadores/metabolismo , Ácidos Graxos/metabolismo , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Gônadas/efeitos dos fármacos , Gônadas/metabolismo , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Músculos/efeitos dos fármacos , Músculos/metabolismo , Fenóis/toxicidade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/toxicidade
2.
Environ Sci Pollut Res Int ; 23(18): 18869-82, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27324498

RESUMO

Multiple anthropogenic stressors act simultaneously on the environment, with consequences different from those caused by single-stressor exposure. We investigated how the combination of the invasive mussel Limnoperna fortunei and a widely applied herbicide, Roundup Max®, affected freshwater microscopic communities and water quality. Further, we compared these results with those induced by the combination of the mussel and technical-grade glyphosate. We carried out a 34-day experiment in outdoor mesocosms, applying the following six treatments: 6 mg L(-1) of technical-grade glyphosate (G), the equivalent concentration of glyphosate in Roundup Max® (R), 100 mussels (M), the combination of mussels and herbicide either in the technical-grade or formulated form (MG and MR, respectively), and control (C). Herbicides significantly increased total phosphorus in water; R and MR showed greater initial total nitrogen and ammonium. R increased picoplankton abundance and caused an eightfold increase in phytoplankton, with high turbidity values; G had a lower effect on these variables. Herbicide-mussel combination induced an accelerated dissipation of glyphosate in water (MG 6.36 ± 0.83 mg G g DW(-1) day(-1) and MR 5.16 ± 1.26 mg G g DW(-1) day(-1)). A synergistic effect on ammonium was observed in MR but not in MG. MR and MG had an antagonistic effect on phytoplankton, which showed a drastic reduction due to grazing, as revealed by M. We provide evidence of differential effects of Roundup Max® and technical-grade glyphosate over water quality and microscopic communities, and in combination with mussels. However, in the combination of mussels and herbicides, mussels seem to play a leading role. In the presence of L. fortunei, the effects of higher nutrient availability provided by herbicides addition were counteracted by the filtration activity of mussels, which released nutrients, grazed on picoplankton and phytoplankton, and boosted the development of other primary producers, periphyton and metaphyton.


Assuntos
Glicina/análogos & derivados , Herbicidas/toxicidade , Mytilidae/fisiologia , Fitoplâncton/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Bivalves , Meio Ambiente , Água Doce , Glicina/farmacologia , Glicina/toxicidade , Herbicidas/análise , Nitrogênio/análise , Fósforo/análise , Água , Poluentes Químicos da Água/análise , Qualidade da Água
3.
Diabetes Obes Metab ; 16(10): 910-21, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24666399

RESUMO

AIMS: Recent reports in the literature have suggested that glucagon-like peptide-1 (GLP-1)-based therapies may lead to increased risk of pancreatic pathology leading to chronic pancreatic injury and pancreatic neoplasia. Extensive non-clinical and clinical safety testing was conducted to support the global development of exenatide twice daily, exenatide once weekly and saxagliptin. Our aim was to integrate these non-clinical data obtained with both mechanisms of GLP-1-based drugs to provide complementary data regarding the potential for drug-induced pancreatic safety signals. METHODS: More than 70 regulated non-clinical toxicology studies in rodents and non-rodents were conducted in accordance with International Conference on Harmonisation and US Food and Drug Administration guidance documents, current industry standards, animal welfare regulations and in compliance with Good Laboratory Practice regulations. Treatment duration was up to 2 years in rodents and up to 12 months in non-rodents using high doses representing large multiples of human exposures (up to 130× for exenatide and 2200× for saxagliptin). Comprehensive pancreas assessments involved more than 2400 pancreata from animals exposed to exenatide and over 1700 pancreata from animals exposed to saxagliptin. RESULTS: Neither exenatide nor saxagliptin treatment resulted in drug-related microscopic changes indicative of acute or chronic adverse effects (including neoplasia) in the endocrine or exocrine pancreas, at doses far exceeding the maximum human systemic exposures. CONCLUSIONS: These data substantially add to the weight of evidence supporting the lack of non-clinical drug-induced pancreatic safety signals in animals exposed to GLP-1-based therapies.


Assuntos
Adamantano/análogos & derivados , Diabetes Mellitus Experimental/tratamento farmacológico , Dipeptídeos/farmacologia , Peptídeo 1 Semelhante ao Glucagon/agonistas , Pâncreas/patologia , Peptídeos/farmacologia , Peçonhas/farmacologia , Adamantano/farmacologia , Animais , Cães , Exenatida , Haplorrinos , Injeções Subcutâneas , Dose Máxima Tolerável , Camundongos , Tamanho do Órgão , Pâncreas/efeitos dos fármacos , Ratos
4.
Mar Pollut Bull ; 73(2): 470-84, 2013 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-23428288

RESUMO

To reduce the negative effect of climate change on Biodiversity, the use of geological CO2 sequestration has been proposed; however leakage from underwater storages may represent a risk to marine life. As extracellular homeostasis is important in determining species' ability to cope with elevated CO2, we investigated the acid-base and ion regulatory responses, as well as the density, of sea urchins living around CO2 vents at Vulcano, Italy. We conducted in situ transplantation and field-based laboratory exposures to different pCO2/pH regimes. Our results confirm that sea urchins have some ability to regulate their extracellular fluid under elevated pCO2. Furthermore, we show that even in closely-related taxa divergent physiological capabilities underlie differences in taxa distribution around the CO2 vent. It is concluded that species distribution under the sort of elevated CO2 conditions occurring with leakages from geological storages and future ocean acidification scenarios, may partly be determined by quite subtle physiological differentiation.


Assuntos
Dióxido de Carbono/análise , Ecossistema , Ouriços-do-Mar/fisiologia , Poluentes Químicos da Água/análise , Adaptação Fisiológica , Animais , Mudança Climática , Fenômenos Geológicos , Concentração de Íons de Hidrogênio , Itália , Água do Mar/química
5.
Nutr Metab Cardiovasc Dis ; 23(5): 473-80, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22209740

RESUMO

BACKGROUND AND AIMS: The relevance of folate, other B-vitamins and homocysteine (Hcy) for the occurrence or prevention of several diseases has induced growing interest. Unfortunately, little evidence is available regarding B-vitamin concentrations in Italy. This study evaluated in a region of middle-southern Italy, folate, vitamin B12 and Hcy concentrations and the prevalence of their ideal blood levels. The main determinants of B-vitamins and Hcy were also considered. METHODS AND RESULTS: Male and female blood donors (n=240), aged 18-66 years and living in Molise region (Italy), were enrolled in the study. They completed a brief questionnaire concerning fruit and vegetables intake, physical activity and smoking; serum and red blood cell (RBC) folate and serum vitamin B12 were measured by an immunoassay on an automated analyzer. Total Hcy was measured by high performance liquid chromatography (HPLC). Geometric means of serum folate, RBC folate and serum vitamin B12 were 10.8nmoll(-1), 426.0nmoll(-1) and 245.0pmoll(-1), respectively. Only 22.5%, 24.2% and 16.3% of blood donors showed an adequate level of serum folate, RBC folate or serum vitamin B12 respectively. When a cut-off of RBC folate ≥906nmoll(-1) was used no women of childbearing age had adequate levels. A geometric mean of 14.0µmoll(-1) was found for total Hcy, with an ideal concentration in 12.1% of subjects. Folate concentration was higher in women and non-smokers and in subjects with higher consumption of fruit and vegetable. CONCLUSION: This study shows a low-moderate B-vitamins status in middle-southern Italy, associated with an inadequate fruit and vegetable consumption. A public health strategy should be undertaken to encourage a B-vitamin-rich diet with the addition of vitamin supplements or vitamin fortified foods in population subgroups with special needs.


Assuntos
Doadores de Sangue , Comportamento Alimentar , Ácido Fólico/sangue , Homocisteína/sangue , Vitamina B 12/sangue , Adolescente , Adulto , Idoso , Cromatografia Líquida de Alta Pressão , Feminino , Frutas , Humanos , Itália , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Atividade Motora , Manejo de Espécimes , Inquéritos e Questionários , Verduras , Adulto Jovem
6.
Infect Dis Rep ; 4(2): e37, 2012 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-24470951

RESUMO

Zoonotic infections are on the increase worldwide, but most research into the biological, environmental and life science aspects of these infections has been conducted in separation. In this review we bring together contemporary research in these areas to suggest a new, symbiotic framework which recognises the interaction of biological, economic, psychological, and natural and built environmental drivers in zoonotic infection and transmission. In doing so, we propose that some contemporary debates in zoonotic research could be resolved using an expanded framework which explicitly takes into account the combination of motivated and habitual human behaviour, environmental and biological constraints, and their interactions.

7.
Pathologica ; 103(5): 271-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22393682

RESUMO

Synovial sarcoma (SS) is a soft tissue neoplasm with clearly defined histologic, immunohistochemical and molecular features that usually arises in the extremities of young adults. The occurrence of these tumors in the kidney is extremely rare and have been prevalently described in case reports. The objectives of this work were to evaluate the frequency of primary renal synovial sarcomas and the pathologic progression in recognition of this possibly under-diagnosed entity. A comprehensive review of the literature has also been performed with a focus on survival. We report the clinico-pathological features of an intrarenal SS occurring in a 67-year-old man. The tumour, measuring 4 cm in its greatest diameter, completely replaced the cortex and the medulla of the inferior region of the left kidney compressing the iliopsoas muscle. Radiological imaging was consistent with a renal cell carcinoma. Histologically, the tumour was composed of atypical monotonous vimentin+, CD99+, bcl-2+ spindle cells exhibiting a haphazard fascicular growth pattern and a high mitotic rate (3 to 5 mitoses per HPF). The diagnosis was supported by reverse transcription-polymerase chain reaction which demonstrated SYT-SSX2 gene fusion. The patient was alive with local recurrence of disease 24 months after surgery. Synovial sarcomas occurring in the kidney, in analogy to other sites, tend to have an aggressive biologic behaviour. Despite being extremely uncommon, with only 44 cases reported to date, they should be included in the differential diagnosis of benign and malignant spindle cell tumours of the kidney. This study also emphasizes the importance of a correct pathologic diagnosis for prognostic and therapeutic implications.


Assuntos
Neoplasias Renais/patologia , Sarcoma Sinovial/patologia , Idoso , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Renais/diagnóstico , Carcinoma de Células Renais/diagnóstico por imagem , Diagnóstico Diferencial , Humanos , Neoplasias Renais/genética , Neoplasias Renais/metabolismo , Masculino , Mitose , Recidiva Local de Neoplasia , Fusão Oncogênica , Proteínas de Fusão Oncogênica/genética , Radiografia , Sarcoma Sinovial/genética , Sarcoma Sinovial/metabolismo , Resultado do Tratamento
8.
J Neurophysiol ; 105(1): 305-20, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21068269

RESUMO

How is the macaque monkey extrastriate cortex organized? Is vision divisible into separate tasks, such as object recognition and spatial processing, each emphasized in a different anatomical stream? If so, how many streams exist? What are the hierarchical relationships among areas? The present study approached the organization of the extrastriate cortex in a novel manner. A principled relationship exists between cortical function and cortical topography. Similar functions tend to be located near each other, within the constraints of mapping a highly dimensional space of functions onto the two-dimensional space of the cortex. We used this principle to re-examine the functional organization of the extrastriate cortex given current knowledge about its topographic organization. The goal of the study was to obtain a model of the functional relationships among the visual areas, including the number of functional streams into which they are grouped, the pattern of informational overlap among the streams, and the hierarchical relationships among areas. To test each functional description, we mapped it to a model cortex according to the principle of optimal continuity and assessed whether it accurately reconstructed a version of the extrastriate topography. Of the models tested, the one that best reconstructed the topography included four functional streams rather than two, six levels of hierarchy per stream, and a specific pattern of informational overlap among streams and areas. A specific mixture of functions was predicted for each visual area. This description matched findings in the physiological literature, and provided predictions of functional relationships that have yet to be tested physiologically.


Assuntos
Macaca/anatomia & histologia , Macaca/fisiologia , Modelos Anatômicos , Modelos Biológicos , Córtex Visual/anatomia & histologia , Córtex Visual/fisiologia , Algoritmos , Animais , Comportamento Animal/fisiologia , Mapeamento Encefálico , Vias Visuais/fisiologia
9.
Minerva Ginecol ; 61(1): 35-43, 2009 Feb.
Artigo em Italiano | MEDLINE | ID: mdl-19204659

RESUMO

The role of minimally invasive surgery in the management of gynecologic cancers is continuously expanding. Although few trials have focused on the safety of laparoscopy in oncology, laparoscopy is now widely used for most gynecological malignancies. Laparoscopy is widely used to manage benign ovarian masses, but its role in managing ovarian cancer still needs to be defined. The role of laparoscopy in ovarian cancer surgery may be divided into three following categories: 1) laparoscopic staging of apparent early ovarian cancer; 2) laparoscopic assessment of disease extent and potential for resectability; 3) laparoscopic reassessment, or second-look operation, or rule out recurrence. Laparoscopic approach has shown several advantages like a reduction in operating time, blood loss, hospital stay, and total hospital charges. The limitations of laparoscopic practice include inadequate port-site metastasis, tumour dissemination due to cyst rupture and incomplete staging. In addition, there were limitations in performing extensive laparoscopic sampling of areas of tumor persistence including retroperitoneal lymph nodes. In literature there are no randomized studies assessing the use of laparoscopy in the management of ovarian cancer. Moreover, most of the studies in literature comparing laparoscopy and laparotomy are carried out by surgeons specialized in one of two approaches, so that the results can not be compared.


Assuntos
Carcinoma/patologia , Carcinoma/cirurgia , Laparoscopia/métodos , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/cirurgia , Carcinoma/diagnóstico , Ensaios Clínicos como Assunto , Medicina Baseada em Evidências , Feminino , Humanos , Laparoscopia/efeitos adversos , Tempo de Internação , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Inoculação de Neoplasia , Estadiamento de Neoplasias , Neoplasias Ovarianas/diagnóstico , Resultado do Tratamento
10.
J Exp Psychol Hum Percept Perform ; 34(5): 1066-77, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18823195

RESUMO

Human subjects practiced navigation in a virtual, computer-generated maze that contained 4 spatial dimensions rather than the usual 3. The subjects were able to learn the spatial geometry of the 4-dimensional maze as measured by their ability to perform path integration, a standard test of spatial ability. They were able to travel down a winding corridor to its end and then point back accurately toward the occluded origin. One interpretation is that the brain substrate for spatial navigation is not a built-in map of the 3-dimensional world. Instead it may be better described as a set of general rules for manipulating spatial information that can be applied with practice to a diversity of spatial frameworks.


Assuntos
Adaptação Fisiológica , Aprendizagem em Labirinto , Orientação , Percepção Espacial , Adulto , Feminino , Humanos , Masculino , Resolução de Problemas , Rotação , Interface Usuário-Computador
11.
Bioorg Med Chem Lett ; 16(18): 4917-21, 2006 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-16824753

RESUMO

A series of potent and selective inhibitors of h-MCH-R1 has been developed based on the piperidine glycineamide compounds I and II. These structurally more rigid tetrahydroisoquinolines (III and IV) showed better pharmacokinetics. The highly potent compounds 12d and 12g displayed excellent rat pk.


Assuntos
Receptores de Somatostatina/antagonistas & inibidores , Tetra-Hidroisoquinolinas/síntese química , Tetra-Hidroisoquinolinas/farmacologia , Animais , Benzimidazóis/química , Humanos , Estrutura Molecular , Ratos , Receptores de Somatostatina/metabolismo , Relação Estrutura-Atividade , Tetra-Hidroisoquinolinas/química , Tetra-Hidroisoquinolinas/farmacocinética
12.
Artigo em Inglês | MEDLINE | ID: mdl-17209294

RESUMO

Brain disorders (psychiatric, neurological and neurosurgical diseases) are leading causes of disease and disability. According to WHO data they cause 35% of the burden of all diseases in Europe. The present study aims to estimate the cost of defined brain disorders and adds all selected disorders to arrive at the total cost for Luxembourg. A model combining published economic and epidemiological data retrieved from the OECD (Organization for Economic Co-operation and Development) and Eurostat databases on brain disorders in Europe (EU member countries, Iceland, Norway and Switzerland) was used. We transformed and converted data for a defined period into the same currency (Euro 2004) and adjusted country specific economic data for purchasing power and relative size of economy and imputed data where no local data were available. There are an estimated 123000 people in Luxembourg currently living with a brain disorder. The total annual cost of brain disorders is estimated at Euro 500 million in 2004 or an average of Euro 1100 per inhabitant. Mental disorders constitute 62% of the total cost (excluding dementia), followed by neurological diseases (excluding dementia) 22%, neurosurgical diseases excluding herniated discs 2.2%. Direct medical expenditures (outpatient care, hospitalization, drugs) have a share of 32%, direct non-medical costs (social services, informal care, adaptation, transportation) 18% and indirect costs (sick leave, early retirement and premature death) 51%.


Assuntos
Encefalopatias/economia , Encefalopatias/epidemiologia , Efeitos Psicossociais da Doença , União Europeia , Humanos , Luxemburgo/epidemiologia , Transtornos Mentais/economia , Transtornos Mentais/epidemiologia , Organização Mundial da Saúde
13.
Ann Ig ; 16(5): 627-32, 2004.
Artigo em Italiano | MEDLINE | ID: mdl-15552728

RESUMO

The authors have analysed vaccination coverage for measles. The active offer of the vaccine brought about an increase of the vaccination coverage but participation to vaccination proved unsatisfactory between 1995 and 2000. The measles epidemic reported 1367 cases, of which 125 were hospitalised (3 cases presented complications). The target for the next years is to reach a vaccination coverage of 95% or more and recuperate the non vaccinated, starting with the 1990 birth cohort.


Assuntos
Vacina contra Sarampo/administração & dosagem , Sarampo/epidemiologia , Sarampo/prevenção & controle , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Programas de Imunização , Lactente , Itália/epidemiologia , Masculino
14.
Transplant Proc ; 36(3): 502-4, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15110572

RESUMO

AIM: To evaluate the results of treatment of erectile dysfunction (ED) in kidney transplant recipients before and after the advent of sildenafil. MATERIALS AND METHODS: From 1981 through 2002, 971 male patients of mean age 53.4 years received a renal graft. Erectile dysfunction (ED) was investigated in all patients at the first urologic visit posttransplantation. Psycho-sexual support was offered to all patients. Before sildenafil use (1998), our diagnostic approach was complex. From 1998 we tested: serum levels of testosterone, prolactin, and glucose with penile duplex ultrasonography and NPT reserved for selected cases. RESULTS: From 1981 through 1998, 365 male kidney transplant recipients (45%) reported ED. Only 169 patients chose to be treated: 27 responded to psycho-sexual therapy; 3 received testosterone with benefit; 133 had a good results from intracavernosal injection of vasoactive drugs; and 6 received a penile prosthesis. Since 1998, 126 patients reported ED (78.3%). Only 78 chose treatment: 24 patients had a satisfactory response to sildenafil (65% with 50 mg and 35% with 100 mg). PGE1 alone or in combination with papaverine and phentolamine produced a good response in 37 patients; 17 patients did not respond to pharmacotherapy; and 5 received a tricomponent penile prosthesis without complications. The side effects of sildenafil and PGE1 therapy were similar to those reported in the literature. CONCLUSIONS: ED is an important problem in male renal transplant recipients. Cultural resistance to treatment is common. However, treatment with sildenafil citrate and intracavernosal self-injection of PGE1 are well accepted, and prosthetic devices may help in resistant cases.


Assuntos
Disfunção Erétil/etiologia , Transplante de Rim/efeitos adversos , Disfunção Erétil/epidemiologia , Disfunção Erétil/prevenção & controle , Humanos , Falência Renal Crônica/complicações , Masculino , Pessoa de Meia-Idade , Piperazinas/uso terapêutico , Purinas , Estudos Retrospectivos , Citrato de Sildenafila , Sulfonas , Vasodilatadores/uso terapêutico
15.
J Endocrinol Invest ; 26(10): 1008-12, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14759075

RESUMO

The aim of this study was to investigate the regional expression of thyroid hormone nuclear receptor forms (TR(alpha) and TR(beta)) and isoform (TR(alpha1) and TR(beta2)) mRNAs in normal and neoplastic (benignant and malignant) human thyroid tissue. Tumor specimens from patients with thyroid carcinomas (papillary: 5 cases; follicular: 5 cases; anaplastic: 2 cases), thyroid follicular adenomas (7 cases) and tissue from normal thyroid glands (12 cases) were analyzed by in situ hybridization and semiquantitative RT-PCR for the expression of TR(alpha1) and beta, as well as for the isoform alpha2 that does not bind the hormone. In normal tissues, TR(alpha2) was expressed at lower levels compared to TR(alpha1) (alpha1/alpha2 = 4.3). In papillary and follicular carcinomas, the expression of TR(alpha1) and TR(beta) did not change as compared with normal thyroid tissue and adenomas (0.87 +/- 0.15 SD vs 0.89 +/- 0.17 densitometric units, DU, and 0.15 +/- 0.02 vs 0.14 +/- 0.03 DU, respectively). However, the expression of TR(alpha2) was significantly higher in differentiated carcinomas compared to normal thyroid tissue and adenomas (0.47 +/- 0.05 vs 0.20 +/- 0.05 DU, p < 0.05) with alpha1/alpha2 = 1.4. In anaplastic carcinoma all TRs were absent. We concluded that both normal and pathological thyroid tissues, with the exception of anaplastic carcinoma, express all TRs in thyreocites and that differentiated thyroid carcinomas are associated in enhancing the expression of TR(alpha2) mRNA.


Assuntos
Receptores dos Hormônios Tireóideos/metabolismo , Receptores alfa dos Hormônios Tireóideos/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Adenocarcinoma Folicular/genética , Adenocarcinoma Folicular/patologia , Adulto , Northern Blotting , Carcinoma/genética , Carcinoma/metabolismo , Carcinoma Papilar/genética , Carcinoma Papilar/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Hibridização In Situ , RNA Neoplásico/química , RNA Neoplásico/genética , Receptores dos Hormônios Tireóideos/biossíntese , Receptores dos Hormônios Tireóideos/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Glândula Tireoide/metabolismo , Receptores alfa dos Hormônios Tireóideos/biossíntese , Receptores alfa dos Hormônios Tireóideos/genética , Receptores beta dos Hormônios Tireóideos , Neoplasias da Glândula Tireoide/genética
18.
Immunol Lett ; 77(3): 143-50, 2001 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-11410246

RESUMO

Thymic medullary epithelial cells (TMECs) constitute a major stromal cell type, the function of which is incompletely understood. Some TMECs express L-fucose-glycosylated proteins on their plasma membrane; these have been shown to specifically bind the lectin UEA-I. We exploited this observation to investigate the consequences of in situ blockage of TMECs in FTOCs by UEA-I. In UEA-I-treated FTOCs, we noted a decreased cellularity among TCRalphabeta+ but not TCRgammadelta+ cells. In fact, CD3- and CD3lo cortical cells were markedly depleted, while CD3hi cells were unaffected. Since the affected cell subsets are in a different compartment from that where UEA-I binding occurs, it is likely that the effect is mediated through a soluble factor. Two possible mechanisms are proposed: a reduced activation of either TMECs or of medullary thymocytes which normally bind to them, results in lowered production of soluble factors responsible for cortical thymocyte proliferation. Alternately, the binding of UEA-I to TMECs could activate the latter to produce signals inhibitory to cortical thymocytes.


Assuntos
Lectinas/metabolismo , Lectinas de Plantas , Receptores de Antígenos de Linfócitos T alfa-beta/análise , Subpopulações de Linfócitos T/citologia , Timo/citologia , Animais , Complexo CD3/análise , Adesão Celular , Contagem de Células , Sobrevivência Celular , Células Cultivadas , Técnicas de Cocultura , Células Epiteliais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Técnicas de Cultura de Órgãos , Receptores de Antígenos de Linfócitos T gama-delta/análise , Subpopulações de Linfócitos T/imunologia , Timo/embriologia , Timo/metabolismo
19.
Rev Neurosci ; 12(2): 175-85, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11392457

RESUMO

There are currently three main views on the neural basis of visually guided reaching: 1) neurons in the superior parietal lobe guide arm movements in a spatial framework that is centered on the body; 2) neurons in the intraparietal sulcus guide arm movements in a spatial framework that is centered on the eye; 3) neurons in the caudal part of premotor cortex guide arm movements in a spatial framework that is centered on the arm and hand. The three viewpoints are mutually compatible and may fit into a larger pattern. Eye-centered representations of target position, and body-centered representations of arm and hand position, may be integrated to form a hand-centered representation close to the output stage in caudal premotor and primary motor cortex.


Assuntos
Força da Mão/fisiologia , Mãos/fisiologia , Córtex Motor/fisiologia , Movimento/fisiologia , Lobo Parietal/fisiologia , Desempenho Psicomotor/fisiologia , Percepção Espacial/fisiologia , Animais , Mãos/inervação , Humanos , Córtex Motor/citologia , Neurônios/fisiologia , Orientação/fisiologia , Lobo Parietal/citologia
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