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1.
Mol Ecol ; 21(20): 5027-41, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22998157

RESUMO

Arylalkylamine N-acetyltransferase-2 (AANAT2) is the enzyme responsible for the rhythmic production of the time-keeping hormone melatonin. It plays a crucial role in the synchronization of biological functions with changes in the environment. Annual and daily fluctuations in light are known to be key environmental factors involved in such synchronization. Previous studies have demonstrated that AANAT2 activity is also markedly influenced by temperature but the mechanisms through which it impacts the enzyme activity need to be further deciphered. We investigated AANAT2 primary to tertiary structures (3D models) and kinetics in relation to temperature for a variety of Teleost species from tropical to Arctic environments. The results extend our knowledge on the catalytic mechanisms of AANAT enzymes and bring strong support to the idea that AANAT2 diversification was limited by stabilizing selection conferring to the enzyme well conserved secondary and tertiary structures. Only a few changes in amino acids appeared sufficient to induce different enzyme activity patterns. It is concluded that AANAT2 evolution is mainly driven by phylogenetic relationships although catalytic properties (enzyme turnover and substrate affinity) are also under the influence of the respective species normal habitat temperature.


Assuntos
Arilalquilamina N-Acetiltransferase/genética , Ecossistema , Evolução Molecular , Peixes/genética , Temperatura , Sequência de Aminoácidos , Animais , Ritmo Circadiano , Clonagem Molecular , Estabilidade Enzimática , Regulação Enzimológica da Expressão Gênica , Melatonina/biossíntese , Modelos Moleculares , Dados de Sequência Molecular , Filogenia , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Proteínas Recombinantes/genética , Especificidade por Substrato
2.
Cytopathology ; 23(4): 242-9, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21736645

RESUMO

OBJECTIVE: In recent years, therapeutic approaches including cytoreductive surgery followed by intraperitoneal chemotherapy have proven effective in peritoneal carcinomatosis of colorectal origin. If cytology is to be used to include patients in aggressive treatment regimens, it is necessary to evaluate its performance, particularly in terms of specificity. The aim of this study was to assess interobserver agreement for the detection of intraperitoneal free cancer cells (IFCCs) in patients with non-gynaecological adenocarcinomas. METHODS: Over a 5-year period, 1223 patients were recruited in 19 French surgery departments. Peritoneal samples were examined in 14 dispersed pathology laboratories. Giemsa-stained slides were sent to a control reader blind to the previous diagnosis. Discordant cases, concordant positive results and a random selection of negative concordant cases were reviewed by a panel of seven cytopathologists. The 'final diagnosis' was that of the consensus meetings but took into account locally-processed slides. RESULTS: Gathering dubious cases with negative results, a 95.6% concordance was achieved between local readers and the control reader. IFCCs were ascertained by the panel in 85 cases (7.0%). Eight of 873 colorectal cancers cases viewed locally were falsely positive (0.9%). Radiotherapy and neoadjuvant therapy had no impact on the false-positive rate as assessed by final validation by the panel (P > 0.05). Samples initially considered as dubious were reclassified as negative by the panel in 24 of 25 cases (96.0%). CONCLUSIONS: The panel consensus allowed reclassification of most dubious/equivocal peritoneal cytology cases, whereas clearcut distinction between benign and malignant cases was correctly achieved in almost all cases.


Assuntos
Adenocarcinoma/diagnóstico , Neoplasias Colorretais/diagnóstico , Citodiagnóstico , Peritônio/patologia , Adenocarcinoma/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma/diagnóstico , Neoplasias Colorretais/patologia , Humanos , Pessoa de Meia-Idade , Prognóstico , Reprodutibilidade dos Testes , Estudos Retrospectivos
3.
Diabetes Metab Syndr ; 15(5): 102208, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34298274

RESUMO

BACKGROUND: Diabetes mellitus, a metabolic disorder characterized by hyperglycaemia is due to impaired insulin secretion and deficiency. Though effective current drug therapies are available for diabetes, yet glycaemic maintenance remains a challenge without medication adherence. This necessitates a holistic approach to improve clinical outcomes for a better patient health care. METHODS: A prospective, interventional, randomized controlled study was conducted among 97 type 2 diabetic patients for 6 months. The primary outcome measures included patient satisfaction of care assessment by diabetes treatment satisfaction questionnaire (DTSQ) and medication adherence by medication adherence rating scale (MARS). Secondary outcomes included assessment of knowledge, attitude, and perception and laboratory parameters. The collected data was analyzed using paired and unpaired T-test. RESULTS: Of 97 patients randomized to group A (n = 49) and group B (n = 48), there were 3 and 1 drop-out in group A and B, respectively. The mean age of patients was found to be 56.82 ± 4.06 years. At the 6thmonth follow up, significant improvement of glycaemic parameters was observed in group A vs B. Mean MARS and DTSQ scores also improved in group A vs. B (P-value <0.05). CONCLUSION: Pharmacist-provided counselling improves patient compliance, quality of life and satisfaction of care in diabetic patients.


Assuntos
Biomarcadores/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Adesão à Medicação/estatística & dados numéricos , Satisfação do Paciente , Farmacêuticos/estatística & dados numéricos , Qualidade de Vida , Adulto , Idoso , Idoso de 80 Anos ou mais , Glicemia/análise , Feminino , Seguimentos , Hemoglobinas Glicadas/análise , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos
4.
J Fish Biol ; 74(5): 1104-28, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20735622

RESUMO

The phylogenetic relationships among populations of seaperch, Helicolenus spp., in the south-west Pacific were examined with mtDNA markers. Parts of the cytochrome b gene [459 base pair (bp)] and the control region (448 bp) were sequenced in 58 specimens from the south-west Pacific and four specimens of Helicolenus lengerichi from Chile. Only one clade was recognized in New Zealand coastal waters, despite a wide range of colour morphs. This clade also occurred in the mid Tasman Sea on the Norfolk Ridge and around Tasmania and Victoria. A second sympatric clade was identified around Tasmania and Victoria and to the west of New Zealand. A third allopatric clade was identified to the north of New Zealand and in deep water on the Chatham Rise and a fourth clade on the Foundation Seamounts and the Louisville Ridge. Helicolenus lengerichi from Chile formed a fifth clade. Assuming a molecular clock, the clades were estimated to have diverged c. 0.7-2.6 million years ago. Only two clades, around Tasmania and Victoria, were separated using morphology, colour (in live) and dorsal-fin soft ray counts and were confirmed as Helicolenus percoides and Helicolenus barathri. Two characters, orbit diameter and colour variation, previously used to identify two species in New Zealand waters were unreliable characters for species discrimination. Principle component analyses of 11 morphological measures from 67 individuals did not delineate the clades. A canonical discriminant analysis was able to separate four of the five clades, but mean discriminate probabilities were low (77.6%), except for the five Chilean specimens of H. lengerichi (100%).


Assuntos
Evolução Molecular , Percas/genética , Filogenia , Animais , Chile , DNA Mitocondrial/genética , Nova Zelândia , Oceano Pacífico , Percas/anatomia & histologia , Percas/classificação , Análise de Componente Principal , Alinhamento de Sequência , Análise de Sequência de DNA
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 69(5): 1294-300, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18006375

RESUMO

Two types of automatic fitting procedures for EPR spectra of disordered systems have been developed, one based on matrix diagonalization of a general spin Hamiltonian, the other on 2nd order perturbation theory. The first program is based on a previous Fortran code complemented with a newly written interface in Java to provide user-friendly in and output. The second is intended for the special case of free radicals with several relatively weakly interacting nuclei, in which case the general method becomes slow. A least squares' fitting procedure utilizing analytical or numerical derivatives of the theoretically calculated spectrum with respect to the g- and hyperfine structure (hfs) tensors was used to refine those parameters in both cases. 'Rigid limit' ESR spectra from radicals in organic matrices and in polymers, previously studied experimentally at low temperature, were analyzed by both methods. Fluorocarbon anion radicals could be simulated, quite accurately with the exact method, whereas automatic fitting on, e.g. the c-C(4)F(8)(-) anion radical is only feasible with the 2nd order approximative treatment. Initial values for the (19)F hfs tensors estimated by DFT calculations were quite close to the final. For neutral radicals of the type XCF(2)CF(2)* the refinement of the hfs tensors by the exact method worked better than the approximate. The reasons are discussed. The ability of the fitting procedures to recover the correct magnetic parameters of disordered systems was investigated by fittings to synthetic spectra with known hfs tensors. The exact and the approximate methods are concluded to be complementary, one being general, but limited to relatively small systems, the other being a special treatment, suited for S=1/2 systems with several moderately large hfs.


Assuntos
Espectroscopia de Ressonância de Spin Eletrônica/métodos , Fluorocarbonos/química , Compostos Inorgânicos/química , Simulação por Computador
6.
Morphologie ; 90(288): 21-5, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16929817

RESUMO

PURPOSE: Glass slides and standard microscopes associated to a brief review of the lectures with projection slides were used during practical training in histology and histopathology for many years. Today it is necessary to develop new tools to improve teaching, and to face a lower number of teachers, as well the increase of the microscope maintenance costs. The goal of this study was to evaluate the feasibility of virtual slide implantation in several medical schools, the feedback from students, and to develop the interest in microscopic histology. METHODS: We used virtual slides generated by the Samba 2050 system produced by Samba technologies. A collection of all organs for histology training was realized and overviewed by three MD, PhD. A questionnaire was distributed in middle of the year to evaluate the feedback. RESULTS: The feedback of the students is highly positive. Students works faster, on better resources, interactivity between students is increased, and the fact that this is a new modality of teaching raises the students' interest. CONCLUSION: Today the teaching program in two French medical schools (Lyon and Grenoble) include virtual slides alone or in addition to microscopic glass slide examination to teach histology or pathology.


Assuntos
Histologia/educação , Faculdades de Medicina , França , Processamento de Imagem Assistida por Computador/normas , Microscopia/métodos , Patologia/educação , Projetos Piloto , Ensino , Interface Usuário-Computador
7.
Oncogene ; 9(2): 509-16, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8290261

RESUMO

The RET proto-oncogene encodes a transmembrane receptor of the tyrosine kinase family and has frequently been found activated in human thyroid carcinomas of the papillary subtype. In most cases the activation consisted of the fusion of its tyrosine-kinase domain with the 5'-terminal region of a gene designated H4 or D10S170. We have named the resulting H4/RET chimeric oncogene RET/PTC. Another activated form of the RET oncogene has subsequently been found in a thyroid carcinoma and is now referred to as RET/PTC2. Here we report the identification and cloning of a novel rearranged version of the RET oncogene in a human thyroid papillary carcinoma. In this case the tyrosine-kinase domain of RET was fused to a sequence 790 bp long belonging to a new gene that we have named RFG (RET Fused Gene). This novel chimeric oncogene has been designated RET/PTC3. In order to have more insights into the function of RFG we have completely cloned and sequenced its cDNA. RFG predicted amino-acid sequence does not have any significant homology to any already known genes and is ubiquitously expressed in human and mouse tissues. Finally we provide evidence indicating that the rearrangement leading to the generation of RET/PTC3 occurred in vivo in the original tumor DNA.


Assuntos
Carcinoma Papilar/genética , DNA de Neoplasias/genética , Proteínas de Drosophila , Proteínas Proto-Oncogênicas/genética , Proto-Oncogenes/genética , Receptores Proteína Tirosina Quinases/genética , Neoplasias da Glândula Tireoide/genética , Sequência de Aminoácidos , Sequência de Bases , Northern Blotting , Southern Blotting , Clonagem Molecular , Rearranjo Gênico , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-ret , Proteínas Recombinantes de Fusão/genética , Homologia de Sequência de Aminoácidos , Transfecção
8.
J Phys Chem B ; 109(27): 13312-21, 2005 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-16852661

RESUMO

This paper presents an experimental infrared spectroscopic study of the physisorption of trichloroethylene (TCE) and tetrachloroethylene (PCE) on a self-supported high silica ZSM5 zeolite. The evolution of the shape, area, and location of vibration bands of both the adsorbent and the adsorbate is analyzed with respect to the number of sorbed molecules. The state of the adsorbed phase is characterized upon adsorption by comparing the location of the investigated vibration bands with the location of the corresponding vibration bands of the chloroalkenes in gaseous, liquid, and solid phases. The singular behavior of PCE with respect to TCE is seen from the modification of vibration bands of both the adsorbed phase and the adsorbent upon loading. The adsorption process proceeds by stages for PCE, whereas it appears continuous for TCE. Particular micropore loadings are evidenced at 4 and 6.5 molec.uc(-1) for PCE and at 6 molec.uc(-1) for TCE, in agreement with previous macroscopic and microscopic data. In addition, the presence of admolecules induces at least one emerging vibration band located at around 1715 cm(-1), mainly due to a contribution of the microporous surface of the adsorbent.

9.
Hum Gene Ther ; 8(1): 15-25, 1997 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-8989991

RESUMO

Ad CFTR, a replication-deficient adenovirus expressing the human cystic fibrosis transmembrane conductance regulator (CFTR), was administered by aerosolization in a single escalating dose to three pairs (cohorts) of cystic fibrosis (CF) patients. Buffer only was administered to the nose and lungs 9-14 days before nasal instillation of virus followed the day after by aerosolization of Ad CFTR to the lung. Nasal doses (defined in terms of viral plaque forming units, pfu) were 10(5), 10(7), and 4 x 10(8), whereas aerosolized doses were 10(7), 10(8), 5.4 x 10(8) for each cohort, respectively. No acute toxic effects were observed in the first 4 weeks after virus treatment. Shedding of infectious Ad CFTR was never detected, whereas detection of vector DNA sequences and CFTR expression demonstrated DNA transfer to the nose and airways of patients. No significant deviations in immunological and inflammatory parameters were observed in serum and in bronchoalveolar lavage (BAL). Importantly, for all patients, the serum anti-adenovirus antibody levels did not change significantly from baseline and no antibodies against adenovirus were found in BAL.


Assuntos
Adenoviridae/metabolismo , Aerossóis/uso terapêutico , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Terapia Genética , Adolescente , Adulto , Southern Blotting , Lavagem Broncoalveolar , Regulador de Condutância Transmembrana em Fibrose Cística/análise , Regulador de Condutância Transmembrana em Fibrose Cística/genética , DNA/análise , Feminino , Expressão Gênica/genética , Vetores Genéticos/genética , Humanos , Imuno-Histoquímica , Masculino , Mucosa Nasal/citologia , Mucosa Nasal/metabolismo , Reação em Cadeia da Polimerase , RNA Mensageiro/análise
10.
J Comp Neurol ; 223(3): 415-23, 1984 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-6368616

RESUMO

The distribution of enkephalin-like immunoreactivity in the human fetus and infant spinal cord have been studied by indirect immunofluorescence. Enkephalin-like immunoreactive fibers were detectable in the lateral funiculus of fetal spinal cord as early as 10 weeks. At the other fetal ages examined, ranging from 12 to 28 weeks, and in infant, enkephalinlike immunoreactivity was found widely distributed throughout the whole spinal cord. In fetus spinal cord several enkephalin-like immunoreactive cells were sometimes seen scattered in the intermediate gray region. Most of the labeling was, however, represented by thin, varicose, immunofluorescent fibers mainly localized in the intermediate gray regions, in the ventral horn and in the superficial dorsal horn layers where they progressively increased in number. Further, the white matter exhibited enkephalin-like immunoreactive fibers particularly in the lateral funiculus where a dense punctiform immunofluorescence could be seen. On the whole, similar patterns were also visible in infant spinal cord. Thus, the superficial layers of the dorsal horn and the intermediolateral and reticular nuclei areas displayed dense plexuses of immunoreactive fibers. In contrast, the white matter showed only little labeling. In addition, no immunoreactivity was found in fetus and infant dorsal root ganglia. Our results emphasize the wide distribution of the enkephalin-like immunoreactivity in the fetus as in the infant spinal cord and further suggest its first appearance early in fetal life, possibly at the embryonic stage.


Assuntos
Encefalinas/metabolismo , Feto/metabolismo , Medula Espinal/metabolismo , Embrião de Mamíferos/metabolismo , Imunofluorescência , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Medula Espinal/embriologia , Distribuição Tecidual
11.
Neuroscience ; 10(1): 41-55, 1983 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6196680

RESUMO

Using the indirect immunofluorescence method, the distribution of substance P-like-immunoreactivity was studied in spinal cord and dorsal root ganglia of 25 human foetuses ranging from 12 to 29 weeks of gestational age. The spinal cord and dorsal root ganglia of three infants (1 day-, 2 and 4 month-old) were also investigated as a post-natal reference. On the whole, the substance P distribution patterns seen in infants were already visible throughout most of foetal life. The highest density of substance P-like-immunoreactive fibres was localized over the superficial layers of the dorsal grey horn. Punctiform immunofluorescence was often found over the white matter especially in the funiculi dorsalis et lateralis. In the ventral horn, substance P immunoreactive fibres were few and far between in the grey matter and were only detected from foetal stage 16 weeks. In addition, longitudino-frontal sections through the dorsal regions revealed repetitive arrangements of substance P-like-immunoreactive fibres along the whole spinal cord. In dorsal root ganglia only a few immunoreactive cells were observed. These findings demonstrate the wide and early occurrence of substance P-like-immunoreactivity in the human foetus spinal cord and dorsal root ganglia. They suggest that the development of the substance P neuronal system begins early in ontogenesis and is regionally differentiated.


Assuntos
Gânglios Espinais/imunologia , Medula Espinal/imunologia , Substância P/imunologia , Feto , Humanos , Lactente , Recém-Nascido , Distribuição Tecidual
12.
J Endocrinol ; 183(1): 79-90, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15525576

RESUMO

In utero exposure to exogenous anti-androgenic compounds induces a wide range of abnormalities of the reproductive system, including hypospermatogenesis, cryptorchidism and hypospadias. By using rats exposed in utero to the anti-androgenic compound flutamide (0.4, 2 or 10 mg/kg per day), it has been shown that hypospermatogenesis in adult testes could be related to (i) a long-term apoptosis in germ cells but not in somatic Leydig and Sertoli cells as evidenced by the TUNEL approach and (ii) alterations in the mRNA and protein expression of pro- (Bax, Bak, Bid) and anti-apoptotic (Bcl-2, Bcl-w) members of the Bcl-2 family. Indeed, the number of apoptotic germ cells increased with the dose of flutamide administered and the apoptotic germ cells were mainly detected at androgen-dependent stages VII-VIII. Moreover, for the Bcl-2-related proteins that were expressed mainly in the germ cells, a decrease in the levels of anti-apoptotic peptides Bcl-w (60%, P=0.003) and Bcl-2 (90%, P=0.0001) was observed at 2 mg/kg per day flutamide and an increase in levels of the pro-apoptotic Bax (2.3-fold, P=0.0004) was detected at 10 mg/kg per day. In contrast, the levels of pro-apoptotic peptide Bak that was mainly expressed in somatic cells decreased (70%, P=0.0008) at 10 mg/kg per day. Such alterations in Bcl-2-related peptides occurred mainly at the protein level except for Bcl-2 (72%, P=0.0001) and Bak (43%, P=00002) transcripts. Together, these results showed that the apoptosis observed in adult germ cells from rats exposed in utero to flutamide may result from a long-term alteration in the balance between pro- and anti-apoptotic Bcl-2-related molecules in favour of pro-apoptotic proteins. These data further supported the concept of an androgen-dependent fetal programming that is in relation with an alteration of the expression of Bcl-2-related genes/proteins promoting apoptosis in testicular germ cells of adult rats with fetal androgen disruption.


Assuntos
Antagonistas de Androgênios/toxicidade , Desenvolvimento Embrionário/efeitos dos fármacos , Flutamida/toxicidade , Efeitos Tardios da Exposição Pré-Natal , Espermatozoides/efeitos dos fármacos , Antagonistas de Androgênios/metabolismo , Animais , Apoptose/genética , Relação Dose-Resposta a Droga , Feminino , Flutamida/metabolismo , Expressão Gênica/efeitos dos fármacos , Genes bcl-2 , Imuno-Histoquímica/métodos , Marcação In Situ das Extremidades Cortadas , Masculino , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Gravidez , Ratos , Ratos Sprague-Dawley , Espermatogênese/efeitos dos fármacos , Espermatozoides/citologia
13.
Int J Oncol ; 5(3): 489-93, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21559603

RESUMO

Thymomas are thymic tumors composed of epithelial cells with various number of lymphocytes. On the basis of lymphocytes number, they can be histologically classified into predominantly lymphocytic, predominantly epithelial and mixed lympho-epithelial. These tumors are rare and their prognosis is not well known yet. In this study we demonstrate by in situ hybridization the presence of RET transcripts in the medullary part of normal murine thymus and in epithelial thymomas. Conversely RET expression was not detected in the cortical part of the thymus and in thymomas with the predominance of the lymphocytic component, suggesting that its expression could be a specific marker of the predominantly epithelial histotype.

14.
Int J Oncol ; 4(3): 623-6, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21566968

RESUMO

The RET proto-oncogene has been demonstrated to be expressed in medullary thyroid carcinomas and pheochromocytomas, and was mutated in patients with the multiple endocrine neoplasia type 2A (MEN 2A). The results presented herein show its expression in normal human thyroid parafollicular C cells. Since RET is predicted to encode a receptor for a still unknown ligand, these data confirm its involvement in the regulation and growth of these cells.

15.
Int J Oncol ; 7(3): 657-60, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21552887

RESUMO

The B-CPAP cell line was obtained from a human differentiated papillary thyroid carcinoma. Previous studies showed that the cells present thyroid characteristics such as thyroglobulin production, phenotypic alterations such as synthesis of human chorionic gonadotropin hormone (HCG), expression of neuron specific enolase (NSE) and protein S100, and also somatic mutations of p53 and K-rns oncogenes. The present data further characterize this cell line and show an overexpression of transforming growth factor (TGF beta 1) and c-met gene product i.e. the receptor for human growth factor (HGF). The relation between the phenotypic and somatic alterations in the process of malignancy are discussed.

16.
Eur J Endocrinol ; 139(2): 209-16, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9724079

RESUMO

Structural alterations to proto-oncogene sequences may be involved in the pathogenesis of human thyroid neoplasms. We studied 128 thyroid tumours (35 benign and 93 malignant) for ras gene point mutations in three different codons (12, 13 and 61) using a restriction fragment length polymorphism technique and direct sequencing of double-stranded DNA on polymerase chain-reaction-amplified tumour DNA. We found a high frequency of ras mutation for the Ha-ras codon 12 in follicular adenomas (7 of 35), particularly in atypical adenomas (5 of 17), in follicular carcinomas (6 of 19), with a high percentage for Hurthle cell carcinomas (6 of 11), and in papillary carcinomas (4 of 66). Point mutations for other ras genes in different codons studied were weak to absent. No mutation was found in undifferentiated carcinomas (n = 8). The predominant amino acid substitution both in the adenomas and in the differentiated tumours was glycine to valine (GGC to GTC) at position 12 of the Ha-ras gene. Our results obtained on a large series confirm the frequent occurrence of Ha-ras codon 12 gene mutations both in adenomas and in carcinomas. The frequency of ras mutations is linked to the geographical origin of the population studied and varies (0-85%) from one cancer type to another according to published data. Therefore, these mutations are merely an expression of cellular transformation.


Assuntos
Genes ras/genética , Mutação Puntual , Neoplasias da Glândula Tireoide/genética , Adenocarcinoma Folicular/genética , Adenocarcinoma Papilar/genética , Adenoma/genética , Carcinoma/genética , Análise Mutacional de DNA , DNA de Neoplasias/análise , Humanos , Proto-Oncogene Mas , Análise de Sequência de DNA
17.
Eur J Endocrinol ; 134(2): 177-83, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8630516

RESUMO

OBJECTIVE: p53 is a well-known nuclear phosphoprotein encoded by a suppressor gene know to be mutated in various kinds of human tumours. A relationship between p53 gene mutation and tumour progression seems to be a common feature of several neoplasias. DESIGN: In order to investigate the role of p53 mutations in human thyroid tumours, DNA samples derived from fifty-six neoplastic tissues, ranging from benign adenomas to undifferentiated carcinomas, were examined for the presence of p53 gene mutations. METHODS: The analysis has been conducted using polymerase chain reaction (PCR) amplification of the exons 5-9 of the p53 gene followed by single strand conformation polymorphism (SSCP) and sequence analyses. RESULTS: One anaplastic carcinoma and one papillary carcinoma showed p53 gene mutations in exons 5 and 8, respectively. A cell line established from the papillary carcinoma showed the same mutation present in the original tumour. Both p53 mutations were heterozygous. The p53 positive samples were analysed for other genetic alterations frequently detected in human thyroid carcinomas (mutations of the RET, TRK, and ras oncogenes): both p53-mutated samples proved to be mutated at level of codon 13 of the c-Ki-ras gene. CONCLUSIONS: Our data confirm that p53 gene alterations are rare in well-differentiated thyroid tumours, that they are an important requirement for the establishment in culture of human thyroid carcinoma cell lines, and that they can be associated with other genetic alterations, namely ras mutations, in the malignant progression of thyroid tumours.


Assuntos
Genes p53 , Genes ras , Mutação , Neoplasias da Glândula Tireoide/genética , Sequência de Bases , DNA de Neoplasias/análise , Éxons , Humanos , Imuno-Histoquímica , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples
18.
Regul Pept ; 6(3): 219-30, 1983 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6353491

RESUMO

The time of the first appearance and distribution of substance(s) reacting with the bovine pancreatic polypeptide (BPP) antiserum No. 146-6, i.e., BPP-like immunoreactivity, were studied in the gastrointestinal tract of 5-24-week-old human fetuses using an indirect immunoperoxidase method. The first immunostaining was identified at the 12th week of gestation in the oxyntic and colonic mucosa, and at the 10th week in the ileum. Serial sections alternately labelled with BPP and glicentin (GLI-1) antisera show several patterns. In the enteric and oxyntic mucosa, there is a cell population reacting only with the GLI-1 antiserum intermixed with cells containing both BPP-like and GLI-1-like immunoreactivities. In the oxyntic mucosa, however, certain cells might store BPP-like material only. Specificity tests illustrate cross-reactivity occurring in immunocytochemical studies of extrapancreatic BPP. The ability of synthetic BPP or a chemically related peptide, peptide YY to abolish the BPP antiserum immunoreaction, as well as previous radioimmunoassay data, raise the question of the presence of authentic BPP in GLI-1-containing cells.


Assuntos
Sistema Digestório/embriologia , Mucosa Gástrica/citologia , Mucosa Intestinal/citologia , Polipeptídeo Pancreático/análise , Peptídeos/análise , Animais , Complexo Antígeno-Anticorpo , Bovinos , Sistema Digestório/citologia , Feminino , Feto , Idade Gestacional , Humanos , Soros Imunes , Técnicas Imunoenzimáticas , Pâncreas , Peptídeo YY , Gravidez
19.
Regul Pept ; 5(3): 245-56, 1983 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6844665

RESUMO

Immunocytochemistry and radioimmunoassay were used to assess the appearance time and tissue distribution of vasoactive intestinal peptide (VIP) in the digestive tract of the human fetus. By radioimmunoassay, VIP was measurable from 10 weeks of gestation. The peptide was abundantly distributed in the jejuno-ileum and colon, where the tissue peptide concentration rose from 9-14 weeks of gestation (18.4 +/- 4.4 and 22.0 +/- 5.0 pmol/g wet weight, respectively) to 15-21 weeks (83.0 +/- 21.1 and 98.6 +/- 36.4 pmol/g, respectively). Lower concentrations were recorded in pancreas from 9-14 weeks of gestation (4.3 +/- 0.8 pmol/g) to 15-21 weeks (13.9 +/- 3.7 pmol/g). The peptide concentration was 15.6 +/- 1.9 pmol/g in fundus and 25.5 +/- 3.2 pmol/g in antrum from 15 to 21 weeks of gestation. The highest concentration was recorded in duodenum from 15 to 21 weeks of gestation (118.4 +/- 40.8 pmol/g wet weight). Tissue VIP concentration and age were positively correlated in the jejuno-ileum. By immunofluorescence, immunoreactive VIP was localized in nervous fibers in the muscularis externa, in the submucosa and in the lamina propria. Scarce cell bodies were also found in the myenteric plexus. No immunofluorescent endocrine cells were observed. These results suggest: (1) the early appearance of immunoreactive VIP in gut, as early as 10 weeks of gestation; (2) the peptide, localized in nervous structures only, follows the same distribution pattern as that in adults; (3) the development of VIPergic structures is a continuous process, initiated during the 3rd month of pregnancy.


Assuntos
Colo/embriologia , Hormônios Gastrointestinais/biossíntese , Intestino Delgado/embriologia , Pâncreas/embriologia , Estômago/embriologia , Peptídeo Intestinal Vasoativo/biossíntese , Colo/metabolismo , Feminino , Feto , Mucosa Gástrica/metabolismo , Idade Gestacional , Humanos , Intestino Delgado/metabolismo , Pâncreas/metabolismo , Gravidez , Radioimunoensaio
20.
Regul Pept ; 14(2): 145-53, 1986 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2424053

RESUMO

The time of appearance and tissue concentrations of substance P-like immunoreactivity (SP-LI) were studied in 53 human fetuses aged 8-21 weeks. Detectable amounts were present at 8 weeks of gestation in available fragments of spinal cord and intestine. Thereafter, the tissue concentrations were highest in spinal cord, intermediate in hypothalamus and lowest in digestive tract. Except for a significant increase in the intestinal wall, the concentrations did not vary from the 8-14 to the 15-21 week period. At chromatography, SP-LI in extracts of spinal cord and intestine was essentially eluted in the volume of the synthetic undecapeptide. Using the indirect immunofluorescence technique, the localization of SP-LI positive structures in the digestive tract was studied in 5 fetuses aged 12-18 weeks. Scarce cell bodies were observed in the myenteric plexus. Nerve fibers were recognized in the muscular layer, in the myenteric plexus and in connective tissue of pancreas. The present results demonstrate the early appearance of SP-LI positive structures both in central nervous system and in the enteric nervous system in the human fetus. In the age range tested, SP-LI concentrations were noticeably higher in spinal cord and hypothalamus than in the digestive tract.


Assuntos
Sistema Digestório/análise , Feto/análise , Hipotálamo/análise , Medula Espinal/análise , Substância P/análise , Sistema Digestório/embriologia , Desenvolvimento Embrionário e Fetal , Feto/fisiologia , Humanos , Hipotálamo/embriologia , Peptídeos/análise , Medula Espinal/embriologia
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