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1.
Sci Rep ; 11(1): 18975, 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34556805

RESUMO

The present study is focused on the development and characterization of innovative cementitious-based composite sensors. In particular, multifunctional cement mortars with enhanced piezoresistive properties are realized by exploiting the concept of confinement of Multiwall Carbon Nanotubes (MWCNTs) and reduced Graphene Oxide (rGO) in a three-dimensional percolated network through the use of a natural-rubber latex aqueous dispersion. The manufactured cement-based composites were characterized by means of Inelastic Neutron Scattering to assess the hydration reactions and the interactions between natural rubber and the hydrated-cement phases and by Scanning Electron Microscopy and X-Ray diffraction to evaluate the morphological and mineralogical structure, respectively. Piezo-resistive properties to assess electro-mechanical behavior in strain condition are also measured. The results show that the presence of natural rubber latex allows to obtain a three-dimensional rGO/MWCNTs segregate structure which catalyzes the formation of hydrated phases of the cement and increases the piezo-resistive sensitivity of mortar composites, representing a reliable approach in developing innovative mortar-based piezoresistive strain sensors.

2.
Epidemiol Infect ; 149: e109, 2021 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-33913410

RESUMO

Conflicting results have been obtained through meta-analyses for the role of obesity as a risk factor for adverse outcomes in patients with coronavirus disease-2019 (COVID-19), possibly due to the inclusion of predominantly multimorbid patients with severe COVID-19. Here, we aimed to study obesity alone or in combination with other comorbidities as a risk factor for short-term all-cause mortality and other adverse outcomes in Mexican patients evaluated for suspected COVID-19 in ambulatory units and hospitals in Mexico. We performed a retrospective observational analysis in a national cohort of 71 103 patients from all 32 states of Mexico from the National COVID-19 Epidemiological Surveillance Study. Two statistical models were applied through Cox regression to create survival models and logistic regression models to determine risk of death, hospitalisation, invasive mechanical ventilation, pneumonia and admission to an intensive care unit, conferred by obesity and other comorbidities (diabetes mellitus (DM), chronic obstructive pulmonary disease, asthma, immunosuppression, hypertension, cardiovascular disease and chronic kidney disease). Models were adjusted for other risk factors. From 24 February to 26 April 2020, 71 103 patients were evaluated for suspected COVID-19; 15 529 (21.8%) had a positive test for SARS-CoV-2; 46 960 (66.1%), negative and 8614 (12.1%), pending results. Obesity alone increased adjusted mortality risk in positive patients (hazard ratio (HR) = 2.7, 95% confidence interval (CI) 2.04-2.98), but not in negative and pending-result patients. Obesity combined with other comorbidities further increased risk of death (DM: HR = 2.79, 95% CI 2.04-3.80; immunosuppression: HR = 5.06, 95% CI 2.26-11.41; hypertension: HR = 2.30, 95% CI 1.77-3.01) and other adverse outcomes. In conclusion, obesity is a strong risk factor for short-term mortality and critical illness in Mexican patients with COVID-19; risk increases when obesity is present with other comorbidities.


Assuntos
COVID-19/mortalidade , Obesidade/complicações , Adulto , COVID-19/complicações , COVID-19/epidemiologia , Estudos de Coortes , Feminino , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Obesidade/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
3.
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
4.
J Psychiatr Res ; 136: 522-528, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33127073

RESUMO

Drop-out from follow-up visits carries significant burden for people diagnosed with depression. The present study assesses multiple clinical moderators of drop-out among depressed outpatients. We retrospectively followed-up 131 outpatients over 6 months: 78 major depressive disorder (MDD), and 53 bipolar disorder (BD-I = 24; BD-II = 29) patients diagnosed according to the Diagnostic and Statistical Manual for Mental Disorders, Fifth Edition. Participants were assessed with standard rating scales administered by experienced psychiatrists. Upon descriptive and Cox regression analyses, 17/53 BDs (32%) dropped-out; the overall survival time until drop-out was 57.94 ± 17.79 days. BD drop-outs were younger, had an earlier age at onset, shorter illness duration, lower rates of lifetime obsessive-compulsive disorder/suicidal behavior, higher rates of substance use disorder (SUD), anxious and mixed features of depression compared to BDs attending up to six months. Among MDD patients, 10/78 cases (13%) dropped-out by month-6 with an average survival of 42.40 ± 16.45 days. Earlier age of onset, younger age, positive family history for mood disorders, lower rates of lifetime generalized anxiety disorder were significantly more frequent among drop-outs than completers, as opposite to SUD, and lifetime recurrent depression. Older age predicted lower drop-out among BDs and MDDs, although with almost null hazard ratio (HR) = 0.928, p < 0.01 vs. HR = 0.941, p < 0.01, respectively. Higher rates of lifetime SUD predicted higher drop-out rates by month-6 among MDDs (HR = 5.477, p = 0.02). Limitations of the study: retrospective design, small sample size, lack of objective measures of treatment-adherence/mood rating during follow-up. Drop-out is common in the real-world setting, warranting specific interventions since the beginning of the treatment.


Assuntos
Transtorno Bipolar , Transtorno Depressivo Maior , Idoso , Transtorno Bipolar/epidemiologia , Transtorno Depressivo Maior/epidemiologia , Manual Diagnóstico e Estatístico de Transtornos Mentais , Humanos , Pacientes Ambulatoriais , Estudos Retrospectivos
5.
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
6.
J Fish Biol ; 80(5): 2112-21, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22497418

RESUMO

The aim of this investigation was to assess the effects of nonylphenol (NP), an oestrogen-like environmental pollutant, on the vitellogenin (VTG) synthesis in adult males of the aplacental viviparous cartilaginous fish Torpedo marmorata. The VTG recovery in males is considered a biomarker of xeno-oestrogenic pollution as this lipophosphoglycoprotein is physiologically induced by oestrogens only in females of oviparous and ovoviparous vertebrates. Using in situ hybridization and immunohistochemistry, T. marmorata males injected with nonylphenol showed the presence of VTG in the liver and the kidney. In particular, vtg messenger (m)RNA and VTG protein were expressed in the liver, whereas in the kidney cells only the presence of VTG was recorded. By contrast, no expression for VTG was detected in the testis. These results demonstrate that in T. marmorata NP induces the expression of vtg only in the liver; the presence of VTG in the kidney and its absence in the testis are discussed.


Assuntos
Fenóis/farmacologia , Torpedo/metabolismo , Vitelogeninas/biossíntese , Animais , Imuno-Histoquímica , Hibridização In Situ , Rim/efeitos dos fármacos , Rim/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Testículo/efeitos dos fármacos , Testículo/metabolismo , Poluentes Químicos da Água/farmacologia
7.
Mol Reprod Dev ; 78(3): 161-71, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21308852

RESUMO

Our knowledge of the molecules that interact with sperm at the egg membrane is restricted to a short list. In the eggs of Discoglossus pictus, fusion with sperm is limited to a differentiated structure, the dimple, offering several advantages for detecting molecules involved in fertilization. Previous studies have identified fucosylated glycoproteins of 200, 260, and 270 kDa located at the surface of the dimple that are able to bind sperm in vitro. Here, we show that dimple glycoproteins and a protein represented by a 120-kDa band released following gel-into-gel SDS-PAGE of both glycoproteins share the same N-terminal amino acid sequence, which itself is similar to the N-termini of Xenopus liver-synthesized vitellogenin (VTG) and the lipovitellin 1. MALDI/MS mass spectrometry indicated that the 120-kDa band is part of both gps 200 and 270/260. A 117-kDa major protein of the egg lysate exhibits the same MALDI/MS spectrum, and LC-MSMS indicates that this is a lipovitellin 1 (DpLIV) that coincides with the 120-kDa band and is responsible for the formation of the 200-270-kDa dimers. Therefore, lipovitellin 1 constitutes the protein backbone of the dimple glycoconjugates. In vitro assays using polystyrene beads coated with DpLIV or with its dimers indicate that significant sperm binding occurs only with DpLIV dimers. In amphibians, VTG is taken up by the oocyte, where it releases lipovitellins destined to form yolk. In Discoglossus, our data suggest that yolk proteins are also synthesized by the oocyte. The dimple forms in the ovulated oocyte following the exocytosis of vesicles that likely expose DpLIVs at their membrane. Indeed, in whole mounts of immunostained eggs, anti-vitellogenin antibodies label only the surface of the dimple.


Assuntos
Anuros/metabolismo , Proteínas do Ovo/genética , Proteínas do Ovo/metabolismo , Interações Espermatozoide-Óvulo/fisiologia , Sequência de Aminoácidos , Animais , Anuros/fisiologia , Western Blotting , Cromatografia Líquida , Dimerização , Eletroforese em Gel de Poliacrilamida , Feminino , Imunofluorescência , Imuno-Histoquímica , Masculino , Microscopia Eletrônica , Dados de Sequência Molecular , Oócitos/ultraestrutura , Alinhamento de Sequência , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrometria de Massas em Tandem
8.
Acta Trop ; 117(3): 189-95, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21172297

RESUMO

We evaluated the effect of Ascaris lumbricoides on Giardia duodenalis infection and TH1/TH2 type immune mechanisms toward this parasite in 251 rural parasitized and 70 urban non-parasitized school children. The children were classified according to light (0-5000 eggs/g faeces) or moderate (>5001-50,000 eggs/g faeces) A. lumbricoides infection. Anti G. duodenalis skin hyper-reactivity, IgE, IgG, IL-13, IFN γ, IL6 and IL-10 levels were compared among G. duodenalis infected and non-infected children according to light or moderate A. lumbricoides infection. It was found that 62% of the A. lumbricoides moderately infected children were co-infected by G. duodenalis compared to 45% of the lightly infected group. After treatment, 42% of the A. lumbricoides moderately group were infected with G. duodenalis compared to 11% of their lightly counterparts, being A. lumbricoides IL-10 levels higher (p<0.0001) in the moderately infected group. In the A. lumbricoides lightly parasitized children, G. duodenalis infection was associated to a significant increase (p<0.005) of the levels of G. duodenalis IL-13, IFN-γ, IL-6, IgE, IgG and skin test hyper reactivity. In contrast, there was no effect of G. duodenalis infection in the elevation of these parameters among the A. lumbricoides moderately parasitized group, being those levels similarly lower as those observed in the control group. Inverse correlations were found between the levels of anti G duodenalis antibodies, skin test hyper-reactivity and cytokines with the intensity of A. lumbricoides infection (p>0.0001) and A. lumbricoides IL-10 levels (p>0.0001), suggesting that co-infection with A. lumbricoides may affect both TH1 and TH2 type immunity against G. duodenalis that may play an important role in the susceptibility to the infection after chemotherapy in children from endemic areas.


Assuntos
Ascaríase/imunologia , Giardíase/imunologia , Imunomodulação , Animais , Anticorpos/imunologia , Ascaríase/complicações , Ascaríase/epidemiologia , Ascaríase/parasitologia , Ascaris lumbricoides/fisiologia , Estudos de Casos e Controles , Criança , Citocinas/imunologia , Giardia lamblia/fisiologia , Giardíase/complicações , Giardíase/epidemiologia , Giardíase/parasitologia , Interações Hospedeiro-Patógeno , Humanos , Hipersensibilidade/imunologia , Imunoglobulinas/imunologia , Contagem de Ovos de Parasitas , População Rural , Índice de Gravidade de Doença , Testes Cutâneos , Equilíbrio Th1-Th2 , Venezuela/epidemiologia
10.
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
11.
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
12.
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
13.
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
14.
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
15.
Diabetes Res Clin Pract ; 68(3): 258-64, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15936469

RESUMO

OBJECTIVE: Strict metabolic control during the 1st year of type 1 diabetes is thought to be a key factor for achieving clinical remission. The aims of this study were two-fold: (i) to evaluate the frequency and duration of spontaneous remission (defined according to the parameters issued by the International Diabetic Immunotherapy Group (IDIG)) in a European population of consecutive recent onset type 1 diabetes patients (aged 5-35 years), followed-up for a period of 36 months with a common protocol of intensive insulin therapy and without adjunct immune-intervention; and (ii) to identify the predictive factors for clinical remission. RESEARCH DESIGN AND METHOD: A total of 189 consecutive patients with newly diagnosed type 1 diabetes according to ADA criteria were recruited in participating centres (Belgium, Czech Republic, Estonia, France, Germany, Hungary, Italy, Poland, Romania, Sweden and Turkey) and followed-up for a period of up to 36 months. In all patients, intensive insulin therapy was implemented consisting of three or four injections of regular insulin daily with NPH insulin at bedtime. Adjustment of insulin dose was made according to a common protocol. Various clinical characteristics (age, gender, severity of presentation, etc.), history (presence of diabetic siblings in the family, etc.) and integrated parameters of metabolic control (HbA(1c), blood glucose, the total insulin dose at hospital discharge adjusted for body weight) were collected. RESULTS: Twenty-two patients (11.6%) experienced remission. The median duration of remission was 9.6 months and the range was 31 months. There was a wide variation among centres. Logistic regression analysis focused on the centre as the main variable in achieving remission. CONCLUSION: Remission was shown to be very heterogeneous between centres depending on 'other factors' such as patient care and family awareness of the disease rather than on 'measurable factors' such as sex, age, HbA(1c) and severity of presentation at diagnosis. Using intensive insulin therapy and optimisation of metabolic control, remission occurred in nearly one out of eight patients.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Adolescente , Adulto , Criança , Pré-Escolar , Esquema de Medicação , Feminino , Seguimentos , Humanos , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Insulina Isófana/administração & dosagem , Insulina Isófana/uso terapêutico , Modelos Logísticos , Masculino , Valor Preditivo dos Testes , Indução de Remissão , Fatores de Tempo
17.
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
18.
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
19.
J Trop Pediatr ; 49(3): 136-42, 2003 06.
Artigo em Inglês | MEDLINE | ID: mdl-12848201

RESUMO

It is well established that malnutrition affects the immune response and increases the susceptibility to parasitic infection. In the present study we evaluated some aspects of the cellular and cytokine network that regulate the IgE responses, which are important components of host defence mechanisms against helminthic parasites in children infected with the intestinal helminth Ascaris lumbricoides, and with differing degrees of malnutrition. We found a defective T cell response in malnourished children, as indicated by diminished levels of circulating total (CD3+), helper (CD4+), IL-2-receptor-bearing (CD4+CD25+) and memory helper T cell responses (CD4+CD45RO+) in keeping with the decreased specific IgE levels against Ascaris lumbricoides. In contrast, the proportions of total B cells (CD20+), and those bearing the low-affinity IgE receptor (CD23+) were increased in the moderated malnourished children. Moreover, serum IL-4 levels and total IgE were also increased in these children. We suggest that malnutrition can cause an imbalance in T cell subpopulations that may lead to a defective T cell maturation and a decreased specific anti-Ascaris IgE response thus increasing the susceptibility to such infections. The high levels of total IgE observed may be related to a non-specific stimulation of the proliferation of activated B cells, probably caused by helminthic parasites and other infectious agents that are frequent in malnourished children.


Assuntos
Anticorpos Anti-Helmínticos/biossíntese , Antígenos de Diferenciação de Linfócitos T/sangue , Ascaríase/imunologia , Ascaris lumbricoides/imunologia , Imunoglobulina E/biossíntese , Distúrbios Nutricionais/imunologia , Análise de Variância , Animais , Antígenos CD/metabolismo , Criança , Fezes/parasitologia , Citometria de Fluxo , Humanos , Imunoglobulina E/sangue , Interleucina-4/sangue , Contagem de Linfócitos , Distúrbios Nutricionais/epidemiologia , Distúrbios Nutricionais/parasitologia , Contagem de Ovos de Parasitas , Teste de Radioimunoadsorção , Venezuela/epidemiologia
20.
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
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