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1.
IEEE J Transl Eng Health Med ; 9: 2700306, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33329944

RESUMO

Objective: To investigate the feasibility of using a wireless wearable device (WD) in differentiated thyroid cancer (DTC) patients undergoing radionuclide therapy with I-131 (RAI) and protected hospitalization, this study compared the measurements of residual radioactivity obtained with those registered by a permanent environmental home device (HD). Methods: Twenty consecutive patients undergoing RAI hospitalized in restricted, controlled areas were enrolled. The patients underwent comprehensive monitoring of vital/nonvital parameters. We obtained 45580± 13 measurements from the WD, detecting the residual radioactivity for each patient during approximately 56 hours of hospitalization, collecting data 53 times per hour. The samples, collected during daily activities, were averaged every two hours, and the results correlated with those from the HD. Bland-Altman analysis was also used to evaluate the agreement between the two techniques. Results: A significant relationship between the WD and HD was observed (r = 0.96, p < 0.0001). Bland-Altman analysis recognized the agreement between measurements by the WD and HD. The mean value at the end of the first day of hospitalization was 80.81 microSv/h and 60.77 microSv/h (p = ns for WD and HD), whereas those at the end of the second day were 47.08 and 24.96 (p = ns). In the generalized linear model (GLM), a similar trend in performance across time was found with the two techniques. Conclusion: This study demonstrates good agreement between the residual radioactivity measures estimated by the WD and HD modalities, rendering them interchangeable. This approach will allow both the optimization of medical staff exposure and safer patient discharge. Abbreviations: wireless device (WD); differentiated thyroid cancer (DTC); radionuclide therapy with I-131 (RAI); home device (HD); generalized linear model (GLM).


Assuntos
Radioatividade , Neoplasias da Glândula Tireoide , Dispositivos Eletrônicos Vestíveis , Estudos de Viabilidade , Humanos , Radioisótopos do Iodo/uso terapêutico , Neoplasias da Glândula Tireoide/radioterapia
2.
J Exp Zool A Ecol Integr Physiol ; 331(1): 52-60, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30246445

RESUMO

Mytilus galloprovincialis female specimens were collected from two mussel farms located in two sites next to Castel dell'Ovo, a historical complex located in the Naples Bay. Such sites were named, respectively, A-area and B-area for the different microbiological parameters so that mussels from A-area can be sold without purification, whereas mussels from B-area must be purified before sale. The mussels were collected during the nonreproductive (summer 2009) and reproductive periods (autumn 2009). Gonadosomatic index, structural organization of the ovary, presence of apoptosis, estrogen receptors expression, as well as the bisphenol A (BPA) content in the ovaries, were evaluated. Ovaries from specimens collected in area B showed a different and significant distribution of the investigated biomarkers as well as of BPA content in respect to those measured in the A-area specimens, confirming that mussels are valid sentinel organisms to biomonitor in the Naples bay too.


Assuntos
Distribuição Animal , Baías , Mytilus/anatomia & histologia , Ovário/anatomia & histologia , Ovário/fisiologia , Animais , Apoptose/fisiologia , Compostos Benzidrílicos/química , Feminino , Itália , Fenóis/química , Reação em Cadeia da Polimerase em Tempo Real , Poluentes Químicos da Água/química
3.
J Small Anim Pract ; 49(11): 552-61, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19006488

RESUMO

Cutaneous "sterile" granulomas represent a group of uncommon skin disorders of unknown aetiopathogenesis. Many diseases are included in this group (for example, sterile granuloma/pyogranuloma syndrome and reactive histiocytosis). The definition of sterile is based on the exclusion of other possible aetiological agents (for example, microorganisms or foreign body). Many techniques are used to rule out a microbial aetiology including cytology, histology, immunohistochemistry and culture. However, some organisms are "fastidious" and difficult to culture or to identify with routine methods, and molecular studies are necessary. This is particularly true for mycobacteria (for example, canine leproid granuloma syndrome) and Leishmania. Recently, studies in human and veterinary medicine have proved the presence of microorganisms (mycobacteria and Leishmania) using a polymerase chain reaction technique in specimens previously diagnosed as sterile. Therefore, it is very important, with the development of new technologies, to use a multidisciplinary diagnostic approach to definitively rule out any microorganism before declaring a disease sterile.


Assuntos
Doenças do Gato/etiologia , Doenças do Cão/etiologia , Granuloma/veterinária , Leishmaniose/veterinária , Infecções por Mycobacterium/veterinária , Dermatopatias Infecciosas/veterinária , Animais , Doenças do Gato/microbiologia , Doenças do Gato/parasitologia , Gatos , Diagnóstico Diferencial , Doenças do Cão/microbiologia , Doenças do Cão/parasitologia , Cães , Reação a Corpo Estranho/complicações , Reação a Corpo Estranho/veterinária , Granuloma/diagnóstico , Granuloma/etiologia , Leishmaniose/diagnóstico , Infecções por Mycobacterium/diagnóstico , Reação em Cadeia da Polimerase , Dermatopatias Infecciosas/complicações , Dermatopatias Infecciosas/diagnóstico
4.
Br J Cancer ; 98(12): 1910-5, 2008 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-18506140

RESUMO

To our knowledge, very few data about the role of Topoisomerase IIalpha (TOPO-IIalpha), an enzyme involved in critical steps of tumour cell proliferation and chemoresistance are currently available in ovarian cancer patients. The aim of this study was to investigate the prognostic value of TOPO-IIalpha expression in a large, single institution series of 96 primary untreated advanced ovarian cancer patients admitted to the Gynecologic Oncology Unit, Catholic University of Campobasso and Rome. Immunohistochemistry was carried out by using the MoAb anti-human TOPO-IIalpha antibody (clone Ki-S1). TOPO-IIalpha immunoreaction was observed in 70 out of 96 cases (72.9%), and the percentages of positively stained cells ranged between 1 and 83% (median=10%). There was no association with clinico-pathological parameters. During the follow up period, progression and death of disease were observed in 76 (79.2%) and 45 (46.9%) cases. A statistically significant direct association between the percentages of positively immunostained tumour cells and the relative risk of death was observed (chi(2)=6.6, P-value=0.0101). In multivariate analysis, only platinum resistance, advanced stage of disease and high levels of TOPO-IIalpha expression retained an independent negative prognostic role for OS. The unfavourable role of high TOPO-IIalpha expression was maintained only in the subgroup of platinum resistant recurrent ovarian cancer patients, be TOPO-IIalpha expression evaluated as continuous variable (chi(2)=5.1, P-value=0.024), or by means of the defined cutoff point. Our study suggests that the assessment of TOPO-IIalpha could be helpful to identify poor prognosis platinum-resistant ovarian cancer patients, potentially candidates to investigational agents.


Assuntos
Antígenos de Neoplasias/metabolismo , DNA Topoisomerases Tipo II/metabolismo , Proteínas de Ligação a DNA/metabolismo , Neoplasias Ovarianas/enzimologia , Idoso , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Prognóstico
5.
Acta Trop ; 103(3): 231-41, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17698018

RESUMO

Asthma and other respiratory diseases have increased in the last years among Venezuelan children from helminthic endemic areas where the infection by Ascaris lumbricoides has been associated to bronchial airway inflammation in parasitized individuals. The aim of this work was to investigate the possible associations between the development of bronchial hyper reactivity and the immune response against A. lumbricoides in urban and rural children. We evaluated 470 school children from rural and urban communities. Pulmonary function tests were performed and >or=20% PC(20) changes were considered as a positive diagnostic of bronchial hyper reactivity. The prevalence and intensity of A. lumbricoides infection was determined by faecal examination. Specific serum IgE levels using a modified ELISA and skin prick tests against A. lumbricoides and the common allergen Dermatophagoides pteronyssinus were done. The number of circulating lymphocyte sub populations was determined by flow cytometry analysis. In rural children, bronchial hyper reactivity was associated with increased specific levels of anti-A. lumbricoides IgE (p<0.0001) and skin test positivity for A. lumbricoides (p<0.0001). The percentage of FEV1 predictive values correlated inversely (p<0.0001) with anti-A. lumbricoides IgE levels. Elevated numbers of circulating CD3+CD4+ and CD20+CD23+ cells were found in rural children with bronchial hyper reactivity compared to their asymptomatic counterparts. They correlated positively with anti-A. lumbricoides IgE levels (p<0.005 and <0.0001, respectively). In contrast, in urban children, bronchial hyper reactivity was associated with elevated anti-D. pteronyssinus IgE levels (p=0. 0089), skin hyper reactivity towards this aero allergen (p=0.003) and to an increase in the number of CD3+CD8+ (p<0.0001). Our results suggest that the IgE response against A. lumbricoides infection may be involved in the development of bronchial hyper reactivity among rural children from endemic areas and also that improved hygienic conditions in the urban environment is associated with increased responses to airborne allergens.


Assuntos
Ascaríase/epidemiologia , Ascaríase/imunologia , Ascaris lumbricoides , Hiper-Reatividade Brônquica/parasitologia , Doenças Endêmicas , Animais , Ascaríase/complicações , Subpopulações de Linfócitos B , Hiper-Reatividade Brônquica/diagnóstico , Criança , Meio Ambiente , Feminino , Humanos , Hipersensibilidade/diagnóstico , Imunoglobulina E/sangue , Contagem de Linfócitos , Masculino , Prevalência , Testes de Função Respiratória , Dermatopatias/complicações , Dermatopatias/diagnóstico , Testes Cutâneos , Subpopulações de Linfócitos T , Venezuela/epidemiologia
6.
Pathol Res Pract ; 203(9): 677-81, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17646054

RESUMO

Endometrial carcinosarcoma is a rare, aggressive disease, accounting for approximately 3% of all uterine neoplasms. The emergence of sarcomatous elements is considered the evolution of subclones arising from high grade endometrial carcinomas. Here, we report two cases of primary endometrial carcinomas recurring as carcinosarcoma. Case 1. a 58-year-old postmenopausal woman diagnosed to have a poorly differentiated endometrial endometrioid adenocarcinoma (FIGO stage IB) developed an intra-abdominal recurrence of disease after 17 months from diagnosis. Histopathological analysis documented a biphasic neoplasia consisting of an epithelial (grade 3 endometrial endometrioid adenocarcinoma) and a sarcomatous component. Salvage chemotherapy with cisplatin, ifosfamide, epirubicin, and then with taxotere was attempted. The patient died after 2 months. Case 2. A 56-year-old woman with a diagnosis of grade 3 endometrial adenosquamous carcinoma of the endometrium (FIGO stage IIIA) experienced pelvic recurrence after five months from completion of chemotherapy. Definitive histology was malignant mixed mesodermal tumor with focal areas of chondrosarcomatous elements. The patient was triaged to exclusive concomitant chemoradiotherapy and salvage chemotherapy. The patient died after 3 months. We describe two cases of high grade endometrial carcinomas recurring as carcinosarcoma, thus providing evidence that the metaplastic sarcomatous evolution is a very rare event which can occur in patients with anaplastic endometrial cancer.


Assuntos
Carcinoma Adenoescamoso/patologia , Carcinoma Endometrioide/secundário , Carcinossarcoma/secundário , Condrossarcoma/secundário , Neoplasias do Endométrio/patologia , Recidiva Local de Neoplasia/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Adenoescamoso/terapia , Carcinoma Endometrioide/terapia , Carcinossarcoma/terapia , Diferenciação Celular , Condrossarcoma/terapia , Terapia Combinada , Neoplasias do Endométrio/terapia , Evolução Fatal , Feminino , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Terapia de Salvação/métodos
7.
Oncogene ; 25(1): 32-42, 2006 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-16170362

RESUMO

Previous work has shown that the Simian Virus 40 T antigen (T antigen) cannot transform mouse embryo fibroblasts (MEFs) that do not express the type 1 insulin-like growth factor receptor (IGF-IR). We have now investigated the mechanism(s) by which the transforming activity of T antigen is affected by IGF-IR signaling. We demonstrate that transformation by T antigen of MEFs and several other cell lines requires an insulin receptor substrate-1 (IRS-1) phosphorylated on tyrosines. If IRS-1 is not expressed, or is serine phosphorylated or otherwise inactive, T antigen fails to transform cells in culture. For instance, while T antigen cannot transform 32D myeloid cells (that do not express IRS-1), its transforming activity is restored by the expression of a wild-type IRS-1, but not of an IRS-1 mutated at the PI3K binding sites. The importance of IRS-1 activation of PI3K in T-antigen transformation is supported by the finding that a constitutively activated p110 subunit of PI3K, a target of IRS-1, overcomes the inability of T antigen to transform MEFs with a serine phosphorylated IRS-1. Taken together, these results indicate that the IRS-1/PI3K signaling is one of the mechanisms regulating transformation by the SV40 T antigen. We propose that the requirement for a tyrosyl-phosphorylated IRS-1 provides a mechanism to explain the failure of T antigen to transform MEFs with deleted IGF-IR genes.


Assuntos
Antígenos Transformantes de Poliomavirus/química , Linhagem Celular Transformada , Fibroblastos/metabolismo , Fosfoproteínas/metabolismo , Receptor IGF Tipo 1/metabolismo , Ágar/química , Animais , Antígenos Transformantes de Poliomavirus/metabolismo , Antígenos Virais de Tumores/química , Sítios de Ligação , Western Blotting , Neoplasias da Mama/metabolismo , Linhagem Celular , Sobrevivência Celular , Transformação Celular Neoplásica , Células Cultivadas , Deleção de Genes , Proteínas Substratos do Receptor de Insulina , Camundongos , Mutação , Neurônios/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Proteínas Pol1 do Complexo de Iniciação de Transcrição/metabolismo , RNA/química , RNA Ribossômico/química , Ribossomos/metabolismo , Serina/química , Transdução de Sinais , Fatores de Tempo , Transfecção , Tirosina/química
9.
G Ital Med Lav Ergon ; 25(3): 396-7, 2003.
Artigo em Italiano | MEDLINE | ID: mdl-14582273

RESUMO

Since many years research programs have been set up to study the relationship between asbestos occupational exposure and development of asbestos-related lung diseases in electricity production plants workers. In the year 2000 a new study of asbestos-related lung abnormalities prevalence in italian geothermal and idrothermal power plant maintenance workers was planned. The cohort comprised 3891 subjects. To meet the criteria, only workers in service for at least six months before 1990 and still in service at power plants in May 2000 were included in the study; chest X-rays were taken and made anonymous. Independent reading of X-rays was made by two groups of specialists, and a third reading of selected discordant readings X-rays was made by another group of specialists. A further diagnostic protocol (including HRCT) was planned when two out of three readings showed the presence of asbestos related lung abnormalities. The analysis was made on 3063 subjects (78.7% of the cohort). The number of asbestos-related abnormalities in two out of three X-ray readings was 122 (4%). The further diagnostic protocol, that included occupational and pathological anamnesis and HRCT, confirmed an asbestos-related occupational lung abnormalities in 41 cases (1.3% out of 3063 subjects). The prevalence of asbestos-related lung abnormalities among 3063 power plant maintenance workers was 1.3%. If all the cases of lung abnormalities so far detected (data are still provisional) had developed only in the power plant environment, and not in previous working activities, the prevalence of lung abnormalities would be extremely low. These data support the evidence of limited exposure levels to asbestos in this working environment And bears witness to the success of preventive measures to control this specific risk.


Assuntos
Amianto/efeitos adversos , Pneumopatias/epidemiologia , Doenças Profissionais/epidemiologia , Centrais Elétricas , Humanos , Itália , Pneumopatias/etiologia , Doenças Profissionais/etiologia , Prevalência
10.
Histol Histopathol ; 18(4): 1005-11, 2003 10.
Artigo em Inglês | MEDLINE | ID: mdl-12973669

RESUMO

Lectins constitute a class of proteins/glycoproteins that specifically bind to terminal glycoside residues. The present investigation aimed to identify lectin-binding sites in developing follicles of Torpedo marmorata. Using eleven lectins (WGA, GSI-A4, GSI-B4, PSA, UEA-I, PNA, MPA, Con-A, DBA, LCA, BPA, SBA), we demonstrated that the biochemical nature and the distribution of carbohydrate residues significantly change during oogenesis in the granulosa cells and the vitelline envelope. In fact, a progressive appearance of surface glycoproteins bearing terminated ss-GlcNAc O-linked side chains was observed in the granulosa during the differentiation of pyriform-like cells from the small ones via intermediate cells simultaneously with a significant reduction of the D-Gal chains present in their nucleus. Glycoproteins bearing ss-GlcNAc O-linked side chains were first evident on the surface of small cells in contact with the oocyte, then on the intermediate ones, and finally on pyriform-like cells. The distribution pattern of such glycoproteins over the differentiated granulosa cells remained unchanged during the subsequent stages of the oocyte growth so granulosa cells preserved the same sugar distribution pattern. Furthermore, a progressive loss of D-Gal residues was evident in the nucleus of granulosa cells. In fact, staining for D-Gal was intense in the nucleus of small follicle cells and progressively reduced till disappearing in differentiated pyriform-like cells. Conversely, the small follicle cells located under the basal lamina were devoid of ss-GlcNAc residues, and the nuclear content in D-Gal remained unchanged. This finding strongly suggests that surface glycoproteins containing ss-GlcNAc residues, and the nuclear content in D-Gal might be related to the differentiation of pyriform-like cells. The present investigation also demonstrates that the content of the sugar residues of the vitelline envelope (VE) changes during oocyte growth, suggesting that pyriform-like cells may contribute to its formation.


Assuntos
Glicosídeos/metabolismo , Células da Granulosa/fisiologia , Folículo Ovariano/metabolismo , Folículo Ovariano/fisiologia , Torpedo/fisiologia , Membrana Vitelina/crescimento & desenvolvimento , Animais , Sítios de Ligação , Diferenciação Celular/fisiologia , Feminino , Fluoresceína-5-Isotiocianato , Corantes Fluorescentes , Glicoproteínas/metabolismo , Lectinas , Proteínas/metabolismo
11.
J Exp Zool ; 290(7): 769-76, 2001 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11748625

RESUMO

The present investigation demonstrates that in squamate reptiles, as already reported for Podarcis sicula (Andreuccetti et al., 2001), the differentiation of pyriform cells from small, stem follicle cells is characterized by the progressive appearance on the cell surface of glycoproteins bearing alpha-GalNAc terminated O-linked side chains. Using a lectin panel (WGA, GSI-A4, GSI-B4, PSA UEA-I, PNA, Con-A, DBA, LCA, BPA, SBA), we demonstrated that, during previtellogenesis, the pattern of distribution of DBA binding sites over the follicular epithelium dramatically changes. In fact, binding sites first appear in follicular epithelium at the time that small cells begin to differentiate; in such follicles, labeling is evident on the cell surfaces of small and intermediate cells. Later on, as the differentiation progresses, the binding sites also become evident on the cell surface of pyriform cells. Once differentiated, the pattern of the distribution of DBA binding sites over the follicular epithelium does not change. By contrast, during the phase of intermediate and pyriform cell regression, DBA binding sites gradually decrease, so that the monolayered follicular epithelium of vitellogenic follicles, constituted only by small cells, shows no binding sites for DBA. It is noteworthy that binding sites for DBA are present on small cells located in contact with the oocyte membrane, but not on those located under the basal lamina or among pyriform cells, and therefore not engaged in the differentiation into pyriform cells. This finding demonstrates that, in squamates, the pattern of distribution of alpha-N-GalNAc containing glycoproteins significantly changes during previtellogenesis, and that these modifications are probably related to the differentiation of small stem cells into highly specialized pyriforms.


Assuntos
Acetilgalactosamina/biossíntese , Diferenciação Celular , Lagartos/fisiologia , Glicoproteínas de Membrana/biossíntese , Oócitos/crescimento & desenvolvimento , Folículo Ovariano/fisiologia , Células-Tronco/fisiologia , Acetilgalactosamina/análise , Animais , Sítios de Ligação , Feminino , Lectinas , Glicoproteínas de Membrana/análise , Vitelogênese
12.
Mol Cell Biol ; 21(16): 5447-58, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11463827

RESUMO

Id proteins are known to play important roles in the proliferation and differentiation of many cell types. The type 1 insulin-like growth factor receptor (IGF-IR), activated by its ligand, induces the differentiation of 32D IGF-IR cells, a murine hematopoietic cell line, expressing a human IGF-IR. Expression in 32D IGF-IR cells of a dominant negative mutant of Stat3 (DNStat3) inhibits IGF-I-mediated differentiation. DNStat3 causes a dramatic increase in Id2 gene expression. This increase, however, is IGF-I dependent and is abrogated by a mutation at tyrosine 950 of the IGF-IR. These results indicate that in 32D cells, the IGF-IR regulates the expression of the Id2 gene and that this regulation is modulated by both positive and negative signals. Our results also suggest that in this model, Id2 proteins influence the differentiation program of cells but are not sufficient for the full stimulation of their proliferation program.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Fator de Crescimento Insulin-Like I/fisiologia , Receptor IGF Tipo 1/fisiologia , Proteínas Repressoras , Transativadores/fisiologia , Fatores de Transcrição/fisiologia , Animais , Linhagem Celular , Humanos , Proteína 1 Inibidora de Diferenciação , Camundongos , Fator de Transcrição STAT3 , Transdução de Sinais , Tirosina
13.
J Biol Chem ; 276(28): 25990-6, 2001 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-11352919

RESUMO

The type 1 insulin-like growth factor receptor (IGF-IR) sends a strong anti-apoptotic signal by at least three different pathways. By using mutants of the IGF-IR, we showed that one of the pathways depends on residues of the IGF-IR (serines 1280--1283) that interact with 14.3.3 proteins. The result is the activation of Raf-1 and the mitochondrial translocation of both Raf-1 and Nedd4, a target of caspases. A mutant IGF-IR in which the serines at positions 1280--1283 have been mutated to alanine does not protect from apoptosis and fails to translocate Nedd4 or Raf-1 to the mitochondria. This failure is accompanied by a loss of cytochrome c from the mitochondria. The 14.3.3/Raf-1/Nedd4 pathway is operative in the presence or absence of the insulin receptor substrate-1.


Assuntos
Apoptose/fisiologia , Proteínas de Ligação ao Cálcio/fisiologia , Ligases/fisiologia , Proteínas Proto-Oncogênicas c-raf/fisiologia , Receptor IGF Tipo 1/fisiologia , Ubiquitina-Proteína Ligases , Animais , Transporte Biológico/fisiologia , Linhagem Celular , Complexos Endossomais de Distribuição Requeridos para Transporte , Camundongos , Mitocôndrias/fisiologia , Ubiquitina-Proteína Ligases Nedd4 , Transdução de Sinais
14.
Anat Rec ; 263(1): 1-9, 2001 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-11331965

RESUMO

The present histochemical and cytochemical study using a lectin panel (WGA, GSI-A4, GSI-B4, PSA UEA-I, PNA, LCA, Con-A, DBA, MPA, BPA) has demonstrated that, in Podarcis sicula, the differentiation of small follicle cells into pyriform cells by means of intermediate cells is accompanied by the appearance of glycoproteins bearing alpha-GalNAc terminated O-linked side chains on the cell surface. The distribution of DBA- and MPA-binding sites over the follicular epithelium changed during the different stages of oocyte growth. DBA- and MPA-binding sites first appeared at the beginning of folliculogenesis within the zona pellucida (ZP) and on the surface of small cells, i.e., the stem cells of pyriform cells. Afterward, labeling was evident on the cell surfaces of intermediate cells and, later on, also of pyriform cells. On the other hand, no labeling was detected on the small cells located under the basal lamina, which, reportedly, do not differentiate into pyriform cells (Filosa et al. J. Embryol. Exp. Morphol., 1979; 15:297-316). Once pyriform cells were differentiated, the distribution of DBA- and MPA-binding sites over the follicular epithelium remained unchanged until intermediate and pyriform cells underwent apoptosis (Motta et al. J. Exp. Zool., 1996; 276:233-241) and the follicular epithelium transformed into a monolayer composed of small follicle cells only (Filosa Mon. Zool. Ital., 1973; 7:151-165). During this stage of oocyte growth, DBA and MPA labeling gradually decreased to completely disappear in the follicular epithelium of vitellogenic follicles. It is noteworthy that the observed changes in the distribution of DBA- and MPA-binding sites represent the first evidence recognized by lectins of a gradual modification of surface glycoprotein distribution over the follicular epithelium in the ovarian follicles of nonmammalian vertebrates so far studied. Finally, the zona pellucida (ZP), characterized by the presence of GalNAc, GluNAc, Man, and Gal, was demonstrated to be first synthetized by the oocyte and later on by the follicle cells.


Assuntos
Acetilgalactosamina/análogos & derivados , Lagartos/fisiologia , Glicoproteínas de Membrana/metabolismo , Oogênese/fisiologia , Folículo Ovariano/metabolismo , Folículo Ovariano/fisiologia , Vitelogênese/fisiologia , Acetilgalactosamina/metabolismo , Animais , Sítios de Ligação , Diferenciação Celular/fisiologia , Feminino , Lectinas/química , Lectinas/fisiologia , Lectinas/ultraestrutura , Microscopia Eletrônica , Microscopia de Fluorescência , Folículo Ovariano/ultraestrutura , Ligação Proteica
15.
J Biol Chem ; 276(17): 13867-74, 2001 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-11278691

RESUMO

The Id proteins play an important role in proliferation, differentiation, and tumor development. We report here that Id gene expression can be regulated by the insulin-like growth factor I receptor (IGF-IR), a receptor that also participates in the regulation of cellular proliferation and differentiation. Specifically, we found that the IGF-IR activated by its ligand was a strong inducer of Id2 gene expression in 32D murine hemopoietic cells. This activation was not simply the result of cellular proliferation, as Id2 gene expression was higher in 32D cells stimulated by IGF-I than in cells exponentially growing in interleukin-3. The up-regulation of Id2 gene expression was largely dependent on the presence of insulin receptor substrate-1, a major substrate of the IGF-IR and a potent activator of the phosphatidylinositol 3-kinase (PI3K) pathway. The role of PI3K activity in the up-regulation of Id2 gene expression by the IGF-IR was confirmed by different methods and in different cell types. In 32D cells, the up-regulation of Id2 gene expression by the PI3K pathway correlated with interleukin-3 independence and inhibition of differentiation.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica , Fosfatidilinositol 3-Quinases/metabolismo , Receptor IGF Tipo 1/metabolismo , Proteínas Repressoras , Transdução de Sinais , Fatores de Transcrição , Proteínas Supressoras de Tumor , Animais , Northern Blotting , Western Blotting , Diferenciação Celular , Divisão Celular , Linhagem Celular , Humanos , Proteína 2 Inibidora de Diferenciação , Proteínas Substratos do Receptor de Insulina , Interleucina-3/metabolismo , Ligantes , Camundongos , PTEN Fosfo-Hidrolase , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Plasmídeos/metabolismo , Estrutura Terciária de Proteína , RNA Mensageiro/metabolismo , Retroviridae/genética , Fatores de Tempo , Células Tumorais Cultivadas , Regulação para Cima
16.
Cancer Res ; 60(15): 4222-30, 2000 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-10945634

RESUMO

R- cells are 3T3 cells derived from mouse embryos with a targeted disruption of the type 1 insulin-like growth factor receptor (IGF-IR) genes. R- cells are refractory to transformation by a variety of viral and cellular oncogenes, including an activated Ras. R- cells stably transfected with an activated Ha-Ras (R-Ras cells) fail to form colonies in soft agar. An IGF-IR truncated at residue 1245 cannot transform R- cells, even when strongly overexpressed. However, the combination of the truncated IGF-IR and an activated Ras induces transformation of R- cells. We show here that the Ras oncoprotein is rapidly degraded when R-Ras cells are grown under anchorage-independent conditions and that signaling from the truncated IGF-IR stabilizes Ras. In monolayer cultures, Ras levels remain constant regardless of the presence or absence of IGF-IR signaling. These results directly explain why Ras cannot transform mouse embryo fibroblasts devoid of IGF-IR. They also suggest a more generalized, alternative mechanism for transformation by Ras and, implicitly, another possible way for targeting Ras in tumor cells.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Proteínas Adaptadoras de Transporte Vesicular , Receptor IGF Tipo 1/fisiologia , Transformação Genética/fisiologia , Proteínas ras/fisiologia , Células 3T3/fisiologia , Animais , Adesão Celular/fisiologia , Divisão Celular/fisiologia , Células Cultivadas , Regulação para Baixo , Humanos , Proteínas Substratos do Receptor de Insulina , Camundongos , Fosfoproteínas/fisiologia , Fosforilação , Poli-Hidroxietil Metacrilato , Proteínas/metabolismo , Receptor IGF Tipo 1/genética , Proteínas Adaptadoras da Sinalização Shc , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src , Proteínas ras/metabolismo
17.
J Parasitol ; 86(4): 859-62, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10958474

RESUMO

This report examines the presence of proteolytic activity detected in media collected from in vitro cultures of Giardia intestinalis, and the partial characterization by gelatin-substrate polyacrylamide gel electrophoresis and inhibition studies. Gelatin-substrate polyacrylamide gel electrophoresis revealed 6 bands with proteolytic activity, with estimated molecular weights of 36, 59, 63, 72, 103, and 175 kDa. These bands were not present in the control medium. On the other hand, G. intestinalis trophozoite lysates showed proteolytic bands at 16, 20, 66, 82, 108, and 120 kDa, thus indicating that intracellular proteases could be different from the excretory/secretory (E/S) products. Based on inhibition studies, 2 bands of 59 and 63 kDa were inhibited by iodoacetic acid, indicating the presence of cysteine proteases. Partial inhibition of a band of 36 kDa was found with EDTA, a metal-chelating agent, suggesting the possible presence of metalloproteases. The presence of aspartic and serine proteases were not detected under the assay conditions used. As G. intestinalis E/S may be involved in differentiation mechanisms of the parasite and also be responsible for the mucosal alterations that occur in giardiasis, the characterization of these proteases may facilitate their evaluation as targets in the therapy of the disease.


Assuntos
Giardia lamblia/enzimologia , Peptídeo Hidrolases/isolamento & purificação , Animais , Meios de Cultura , Ácido Edético/farmacologia , Eletroforese em Gel de Poliacrilamida , Ácido Iodoacético/farmacologia , Peso Molecular , Pepstatinas/farmacologia , Peptídeo Hidrolases/química , Peptídeo Hidrolases/metabolismo , Fluoreto de Fenilmetilsulfonil/farmacologia , Inibidores de Proteases/farmacologia
18.
Nurse Pract ; 25(4): 30-2, 35-6, 38 passim; quiz 50-1, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10790797

RESUMO

Neck masses often present a diagnostic challenge to the primary care provider: Etiologies range from benign inflammations to life-threatening malignancies. Categorizing the etiologies into three broad categories is helpful when considering the extensive differential diagnosis for a neck mass: congenital, inflammatory/infectious, and neoplastic causes. This article discusses the evaluation and subsequent determination of whether a neck mass is significant and warrants further evaluation or is insignificant and may simply be observed. By performing a through history and physical examination, primary care providers can narrow the possibilities, differentiate between significant and insignificant neck masses, and select the appropriate treatment.


Assuntos
Cistos/diagnóstico , Neoplasias de Cabeça e Pescoço/diagnóstico , Infecções/diagnóstico , Doenças Linfáticas/diagnóstico , Pescoço , Adolescente , Adulto , Criança , Cistos/congênito , Cistos/terapia , Diagnóstico Diferencial , Feminino , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Infecções/terapia , Doenças Linfáticas/terapia , Masculino
19.
Endocrinology ; 141(4): 1289-300, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10746631

RESUMO

The type 1 insulin-like growth factor receptor (IGF-IR) activates the extracellular signal-regulated kinases (ERK1 and -2). The two major substrates of the IGF-IR, insulin receptor substrate-1 (IRS-1) and the Shc proteins, are known to contribute to this activation. We investigated the domains of the IGF-IR required for the activation of the ERK proteins. To facilitate this study, we used a cell line (32D cells) that lacks IRS-1. In the absence of IRS-1, ERK activation is inhibited if the IGF-IR is mutated at two domains: tyrosine Y950 and a serine quartet at 1280-1283. Expression of IRS-1 in 32D cells expressing the double mutant IGF-IR restores ERK activation. The importance of the C-terminus of the IGF-IR in ERK activation (in the absence of IRS-1) is confirmed by the failure of the insulin receptor to give a sustained activation of ERK. In this model system, there is a good, but not exact, correlation between ERK activation and cell survival after withdrawal of growth factors.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Proteínas Adaptadoras de Transporte Vesicular , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/fisiologia , Linhagem Celular/fisiologia , Sobrevivência Celular , Ativação Enzimática/fisiologia , Inibidores Enzimáticos/farmacologia , Flavonoides/farmacologia , Proteínas Substratos do Receptor de Insulina , Fosfoproteínas , Fosforilação , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas/metabolismo , Proteínas Proto-Oncogênicas/fisiologia , Proteínas Proto-Oncogênicas c-akt , Proteínas Adaptadoras da Sinalização Shc
20.
Mol Cell Biol ; 19(10): 7203-15, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10490655

RESUMO

The type 1 insulin-like growth factor receptor (IGF-1R), activated by its ligands, protects several cell types from a variety of apoptotic injuries. The main signaling pathway for IGF-1R-mediated protection from apoptosis has been previously elucidated and rests on the activation of phosphatidylinositol 3-kinase, Akt/protein kinase B, and the phosphorylation and inactivation of BAD, a member of the Bcl-2 family of proteins. In 32D cells (a murine hemopoietic cell line devoid of insulin receptor substrate 1 [IRS-1]), the IGF-1R activates alternative pathways for protection from apoptosis induced by withdrawal of interleukin-3. One of these pathways leads to the activation of mitogen-activated protein kinase, while a third pathway results in the mitochondrial translocation of Raf and depends on the integrity of a group of serines in the C terminus of the receptor that are known to interact with 14.3.3 proteins. All three pathways, however, result in BAD phosphorylation. The presence of multiple antiapoptotic pathways may explain the remarkable efficacy of the IGF-1R in protecting cells from apoptosis.


Assuntos
Apoptose , Proteínas Serina-Treonina Quinases , Receptor IGF Tipo 1/metabolismo , Proteínas de Transporte/metabolismo , Proteínas Substratos do Receptor de Insulina , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mutação , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Fosfoproteínas/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt , Receptor IGF Tipo 1/genética , Receptor de Insulina/metabolismo , Serina/genética , Transdução de Sinais , Proteína de Morte Celular Associada a bcl
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