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1.
Hum Reprod ; 28(5): 1210-20, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23462389

RESUMO

STUDY QUESTION: Is it feasible to identify factors that significantly affect the clinical outcome of IVF-ICSI cycles and use them to reliably design a predictor of implantation? SUMMARY ANSWER: The Bayesian network (BN) identified top-history embryos, female age and the insemination technique as the most relevant factors for predicting the occurrence of pregnancy (AUC, area under curve, of 0.72). In addition, it could discriminate between no implantation and single or twin implantations in a prognostic model that can be used prospectively. WHAT IS KNOWN ALREADY: The key requirement for achieving a single live birth in an IVF-ICSI cycle is the capacity to estimate embryo viability in relation to maternal receptivity. Nevertheless, the lack of a strong predictor imposes several restrictions on this strategy. STUDY DESIGN, SIZE, DURATION: Medical histories, laboratory data and clinical outcomes of all fresh transfer cycles performed at the International Institute for Reproductive Medicine of Lugano, Switzerland, in the period 2006-2008 (n = 388 cycles), were retrospectively evaluated and analyzed. PARTICIPANTS/MATERIALS, SETTING, METHODS: Patients were unselected for age, sperm parameters or other infertility criteria. Before being admitted to treatment, uterine anomalies were excluded by diagnostic hysteroscopy. To evaluate the factors possibly related to embryo viability and maternal receptivity, the class variable was categorized as pregnancy versus no pregnancy and the features included: female age, number of previous cycles, insemination technique, sperm of proven fertility, the number of transferred top-history embryos, the number of transferred top-quality embryos, the number of follicles >14 mm and the level of estradiol on the day of HCG administration. To assess the classifier, the indicators of performance were computed by cross-validation. Two statistical models were used: the decision tree and the BN. MAIN RESULTS AND THE ROLE OF CHOICE: The decision tree identified the number of transferred top-history embryos, female age and the insemination technique as the features discriminating between pregnancy and no pregnancy. The model achieved an accuracy of 81.5% that was significantly higher in comparison with the trivial classifier, but the increase was so modest that the model was clinically useless for predictions of pregnancy. The BN could more reliably predict the occurrence of pregnancy with an AUC of 0.72, and confirmed the importance of top-history embryos, female age and insemination technique in determining implantation. In addition, it could discriminate between no implantation, single implantation and twin implantation with the AUC of 0.72, 0.64 and 0.83, respectively. LIMITATIONS, REASONS FOR CAUTION: The relatively small sample of the study did not permit the inclusion of more features that could also have a role in determining the clinical outcome. The design of this study was retrospective to identify the relevant features; a prospective study is now needed to verify the validity of the model. WIDER IMPLICATIONS OF THE FINDINGS: The resulting predictive model can discriminate with reasonable reliability between pregnancy and no pregnancy, and can also predict the occurrence of a single pregnancy or multiple pregnancy. This could represent an effective support for deciding how many embryos and which embryos to transfer for each couple. Due to its flexibility, the number of variables in the predictor can easily be increased to include other features that may affect implantation. STUDY FUNDING/COMPETING INTERESTS: This study was supported by a grant, CTI Medtech Project Number: 9707.1 PFLS-L, Swiss Confederation. No competing interests are declared.


Assuntos
Técnicas de Apoio para a Decisão , Transferência Embrionária/métodos , Fertilização in vitro/métodos , Injeções de Esperma Intracitoplásmicas/métodos , Algoritmos , Área Sob a Curva , Teorema de Bayes , Implantação do Embrião , Feminino , Humanos , Masculino , Idade Materna , Oócitos/citologia , Gravidez , Resultado da Gravidez , Probabilidade , Prognóstico , Reprodutibilidade dos Testes , Espermatozoides/metabolismo
2.
Cell Death Differ ; 12(11): 1378-89, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15947792

RESUMO

Plasma membrane lipid microdomains have been considered as a sort of 'closed chamber', where several subcellular activities, including CD95/Fas-mediated proapoptotic signaling, take place. In this work we detected GD3 and GM3 gangliosides in isolated mitochondria from lymphoblastoid CEM cells. Moreover, we demonstrated the presence of microdomains in mitochondria by immunogold transmission electron microscopy. We also showed that GD3, the voltage-dependent anion channel-1 (VDAC-1) and the fission protein hFis1 are structural components of a multimolecular signaling complex, in which Bcl-2 family proteins (t-Bid and Bax) are recruited. The disruption of lipid microdomains in isolated mitochondria by methyl-beta-cyclodextrin prevented mitochondria depolarization induced by GD3 or t-Bid. Thus, mitochondrion appears as a subcompartmentalized organelle, in which microdomains may act as controllers of their apoptogenic programs, including fission-associated morphogenetic changes, megapore formation and function. These results disclose a new scenario in which mitochondria-associated lipid microdomains can act as regulators and catalysts of cell fate.


Assuntos
Apoptose/fisiologia , Gangliosídeo G(M3)/metabolismo , Microdomínios da Membrana/metabolismo , Mitocôndrias/metabolismo , Linfócitos T/metabolismo , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/metabolismo , Humanos , Membranas Intracelulares/metabolismo , Proteínas de Membrana , Microscopia Confocal , Mitocôndrias/efeitos dos fármacos , Proteínas Mitocondriais/metabolismo , Linfócitos T/citologia , Canal de Ânion 1 Dependente de Voltagem/metabolismo , Proteína X Associada a bcl-2/metabolismo , beta-Ciclodextrinas/farmacologia , Receptor fas/metabolismo
3.
Mech Dev ; 96(2): 215-8, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10960786

RESUMO

We examined the pattern of expression in hair follicles of the transcription factor gene Krox-20. During embryogenesis, Krox-20 is first expressed in the upper portion of the hair bud, then in the hair canal, in the sebaceous glands and in the outer root sheath. In the mature follicles, Krox-20, like Shh and TGFbetaRII, is also expressed in a sub-population of matrix keratinocytes located in a ring-like fashion in vibrissal follicles and clustered on one side of the papilla in pelage follicles. This polarized pattern rotates around the papilla as a result of sequential gene expression by individual groups of matrix cells. This peculiar pattern is not linked to follicle angling.


Assuntos
Proteínas de Ligação a DNA/genética , Folículo Piloso/embriologia , Folículo Piloso/metabolismo , Fatores de Transcrição/genética , Animais , Sequência de Bases , Primers do DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteína 2 de Resposta de Crescimento Precoce , Regulação da Expressão Gênica no Desenvolvimento , Genes Precoces , Imuno-Histoquímica , Hibridização In Situ , Óperon Lac , Camundongos , Camundongos Transgênicos , Fatores de Transcrição/metabolismo
4.
J Invest Dermatol ; 114(5): 901-8, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10771469

RESUMO

Members of the vertebrate hedgehog family (Sonic, Indian, and Desert) have been shown to be essential for the development of various organ systems, including neural, somite, limb, skeletal, and for male gonad morphogenesis. Sonic hedgehog and its cognate receptor Patched are expressed in the epithelial and/or mesenchymal cell components of the hair follicle. Recent studies have demonstrated an essential role for this pathway in hair development in the skin of Sonic hedgehog null embryos. We have further explored the role of the hedgehog pathway using anti-hedgehog blocking monoclonal antibodies to treat pregnant mice at different stages of gestation and have generated viable offspring that lack body coat hair. Histologic analysis revealed the presence of ectodermal placode and primodium of dermal papilla in these mice, yet the subsequent hair shaft formation was inhibited. In contrast, the vibrissae (whisker) development appears to be unaffected upon anti-hedgehog blocking monoclonal antibody treatment. Strikingly, inhibition of body coat hair morphogenesis also was observed in mice treated postnatally with anti-hedgehog monoclonal antibody during the growing (anagen) phase of the hair cycle. The hairless phenotype was reversible upon suspension of monoclonal antibody treatment. Taken together, our results underscore a direct role of the Sonic hedgehog signaling pathway in embryonic hair follicle development as well as in subsequent hair cycles in young and adult mice. Our system of generating an inducible and reversible hairless phenotype by anti-hedgehog monoclonal antibody treatment will be valuable for studying the regulation and mechanism of hair regeneration.


Assuntos
Proteínas de Drosophila , Cabelo/embriologia , Proteínas de Insetos/fisiologia , Animais , Anticorpos Monoclonais/imunologia , Feminino , Cabelo/fisiologia , Proteínas Hedgehog , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Morfogênese , Gravidez , Regeneração
5.
FEBS Lett ; 506(1): 45-50, 2001 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-11591368

RESUMO

Efficiency of Fas-mediated apoptosis of lymphoid cells is regulated, among other means, by a mechanism involving its association with ezrin, a cytoskeletal protein belonging to the 4.1 family of proteins. In the present work, we provide evidence for a further molecule that associates to ezrin in Fas-triggered apoptosis, the disialoganglioside GD3. In fact, as an early event, GD3 redistributed in membrane-associated domains in uropods and co-localized with ezrin. Co-immunoprecipitation analyses confirmed this result, indicating a GD3-ezrin association. Altogether, these results are suggestive for a role of GD3 in Fas/ezrin-mediated apoptosis, supporting the view that uropods contain a multimolecular signaling complex involved in Fas-mediated apoptosis.


Assuntos
Apoptose/fisiologia , Gangliosídeos/fisiologia , Fosfoproteínas/metabolismo , Receptor fas/fisiologia , Linhagem Celular , Cromatografia em Camada Fina , Proteínas do Citoesqueleto , Gangliosídeos/metabolismo , Humanos , Microscopia Confocal , Microscopia Eletrônica de Varredura , Microscopia de Fluorescência , Testes de Precipitina
6.
Biosystems ; 43(2): 73-81, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9231906

RESUMO

We describe an artificial ant colony capable of solving the travelling salesman problem (TSP). Ants of the artificial colony are able to generate successively shorter feasible tours by using information accumulated in the form of a pheromone trail deposited on the edges of the TSP graph. Computer simulations demonstrate that the artificial ant colony is capable of generating good solutions to both symmetric and asymmetric instances of the TSP. The method is an example, like simulated annealing, neural networks and evolutionary computation, of the successful use of a natural metaphor to design an optimization algorithm.


Assuntos
Formigas/fisiologia , Modelos Biológicos , Algoritmos , Animais , Simulação por Computador , Locomoção , Feromônios/fisiologia , Processos Estocásticos
7.
Int J Clin Pharmacol Res ; 15(5-6): 175-9, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8835615

RESUMO

In this retrospective trial we report the immediate and long-term effects of rIFN-alpha therapy on serum aminotransferases, especially on their behaviour in relation to the disappearance of serum HCV-RNA at the end of the treatment and one year later. Eighty-eight subjects were eligible in our study. The diagnosis of hepatitis was based on clinical, serological and histological data in all patients. They showed ALT and AST levels at least twice the upper maximum normal value and detectable serum HCV-RNA before the study. These patients were treated with rIFN-alpha 3MU, 3 times a week, in 54 cases for 6 months and in 34 for 1 year. Patients were examined at monthly intervals. Serum HCV-RNA was assessed before and at the end of the treatment and every six months during the follow-up. A complete response was defined exclusively as a normalization of aminotransferases and disappearance of serum HCV-RNA. The two groups were homogeneous. During the treatment drop-outs were 5 (5.7%), and 7 patients (7.9%) stopped the therapy for side-effects. The treatment induced a complete response in 13 (25.4%) of 51 patients treated for 6 months, and in 8 (32%) of 25 cases treated for 12 months. The patients with normalization of aminotransferase levels but with still detectable HCV-RNA in serum were 20 (39.2%) of 51 treated for 6 months and 13 (41.9%) of 31 treated for 12 months. The cases with normalization of aminotransferases were followed up for one year after IFN withdrawal. Serum liver function tests and HCV-RNA were performed every 6 months in these patients. One year after IFN withdrawal the numbers with persistent normalization of liver enzymes and absence of serum HCV/RNA were 9 (69.2%) of 13 cases with complete response after a 6-month course, and 5 (62.5%) of 8 subjects with complete response after a 12-month course. The subjects with continuous normalization or liver enzymes but persistence of serum HCV-RNA at the end of the trial were 3 (15.7%) of 19 patients with normalization of liver enzymes and still detectable HCV-RNA after a 6-month course, and 2 (15.3%) of 13 cases with normalization of liver enzymes and still detectable HCV-RNA after a 12-month course. Overall at the end of our study the patients with normal aminotransferases were 19 (21.5%) of 88 cases studied. 14 of them (73.6%) being from the subjects with disappearance of serum HCV-RNA just after IFN treatment.


Assuntos
Antivirais/administração & dosagem , Hepatite C/tratamento farmacológico , Interferon Tipo I/administração & dosagem , Viremia/tratamento farmacológico , Adulto , Esquema de Medicação , Feminino , Hepacivirus/genética , Hepatite C/virologia , Humanos , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Proteínas Recombinantes
8.
Int J Clin Pharmacol Res ; 17(1): 17-22, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9403349

RESUMO

The aim of this prospective research was to compare, in a seven-year follow-up, the clinical outcome of ulcerative pancolitis with that of non-progressive ulcerative colitis. The activity of the disease was evaluated by a Clinical Activity Index and an Endoscopic Index. Of 112 cases of ulcerative colitis observed, 95 showed no change in extent and were studied as examples of non-progressive UC, and in this group the extension of the disease was: pancolitis in 19%, left-sided colitis in 39%, proctosigmoiditis in 17% and proctitis in 25%. A colectomy had to be performed in 5%. None of the enrolled cases developed a cancer during the follow-up. The patients with ulcerative pancolitis or left-sided colitis were treated with 5-ASA 1.6 g/day in a delayed-release formulation, while the cases with proctosigmoiditis or proctitis were treated with 5-ASA enemas 4 g/day. The cases with more than one relapse/year were 39%. The proportion of patients with only one relapse/year was 53%. The patients with steady remission for all the seven years of the trial were only 8%, but with a statistically significant difference between the groups with initial diagnosis of proctosigmoiditis or proctitis and the group with initial diagnosis of pancolitis or left-sided colitis (12% versus 5%). Among the cases with continuous remission, 37% showed colonic alterations, with an endoscopic score higher than 4 but a clinical score less than 6. Side-effects were observed in 6% patients but without treatment withdrawal. Non-progressive ulcerative colitis throughout the colon has a relatively good prognosis which seems to be independent of the location of the disease, even if we have found a statistically significant higher percentage of cases with steady remission among the patients with more distal disease.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Mesalamina/uso terapêutico , Administração Oral , Adulto , Idoso , Anti-Inflamatórios não Esteroides/administração & dosagem , Colite Ulcerativa/patologia , Enema , Estudos de Avaliação como Assunto , Feminino , Humanos , Masculino , Mesalamina/administração & dosagem , Pessoa de Meia-Idade , Recidiva
9.
Int J Tissue React ; 12(4): 243-6, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-1980911

RESUMO

The therapeutic effectiveness and tolerance of 5-aminosalicylic acid (5ASA), compared with Salazosulphapyridine (SASP) in treatment of ulcerative colitis have been evaluated in 86 patients with the disease at a low or medium phase of activity. After a treatment of six weeks, an improvement was noted in 63.6% (5ASA) and 61.3% (SASP) of these patients. However in no case was a complete remission of the disease observed on the basis of endoscopic inspection. In patients with pancolitis the improvement was lower (37.5% with 5ASA, 40% with SASP). The only side-effect was gastric intolerance, which occurred in 18.1% of the 5ASA and in 19% of the SASP patients. In conclusion we can assume that 5ASA and SASP largely overlap each other as regards both therapeutic effectiveness and occurrence of side-effects.


Assuntos
Ácidos Aminossalicílicos/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Ácidos Aminossalicílicos/efeitos adversos , Colite Ulcerativa/patologia , Gastroscopia , Humanos , Mesalamina , Estômago/efeitos dos fármacos , Estômago/patologia , Sulfassalazina/efeitos adversos , Sulfassalazina/uso terapêutico , Fatores de Tempo
10.
Comput Biol Med ; 43(11): 1783-92, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24209924

RESUMO

We present a Bayesian network model for predicting the outcome of in vitro fertilization (IVF). The problem is characterized by a particular missingness process; we propose a simple but effective averaging approach which improves parameter estimates compared to the traditional MAP estimation. We present results with generated data and the analysis of a real data set. Moreover, we assess by means of a simulation study the effectiveness of the model in supporting the selection of the embryos to be transferred.


Assuntos
Teorema de Bayes , Transferência Embrionária/estatística & dados numéricos , Fertilização in vitro/estatística & dados numéricos , Adulto , Algoritmos , Área Sob a Curva , Simulação por Computador , Embrião de Mamíferos , Feminino , Humanos , Gravidez/estatística & dados numéricos
11.
Med Image Comput Comput Assist Interv ; 13(Pt 2): 488-95, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20879351

RESUMO

We propose a technique for recovering the position and depth of pronuclei of human zygotes, from Z-stacks acquired using Hoffman Modulation Contrast microscopy. We use Local Binary Pattern features for describing local texture, and integrate information from multiple neighboring areas of the stack, including those where the object to be detected would appear defocused; interestingly, such defocused areas provide very discriminative information for detection. Experimental results confirm the effectiveness of our approach, which allows one to derive new 3D measurements for improved scoring of zygotes during In Vitro Fertilization.


Assuntos
Algoritmos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Microscopia de Contraste de Fase/métodos , Reconhecimento Automatizado de Padrão/métodos , Zigoto/citologia , Humanos , Aumento da Imagem/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
Artif Life ; 5(2): 137-72, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10633574

RESUMO

This article presents an overview of recent work on ant algorithms, that is, algorithms for discrete optimization that took inspiration from the observation of ant colonies' foraging behavior, and introduces the ant colony optimization (ACO) metaheuristic. In the first part of the article the basic biological findings on real ants are reviewed and their artificial counterparts as well as the ACO metaheuristic are defined. In the second part of the article a number of applications of ACO algorithms to combinatorial optimization and routing in communications networks are described. We conclude with a discussion of related work and of some of the most important aspects of the ACO metaheuristic.


Assuntos
Algoritmos , Formigas , Comportamento Social , Animais , Comportamento Alimentar
13.
Minerva Dietol Gastroenterol ; 36(1): 31-3, 1990.
Artigo em Italiano | MEDLINE | ID: mdl-1970855

RESUMO

The aim of the study was to compare the efficacy and side-effects of 5-ASA and SASP in the treatment of active ulcerative colitis. An improvement was seen in 71.4% (5-ASA) and 70.3% (SASP) but there were no complete remissions. The incidence of improvements was only 36.3% (5-ASA) and 37.5% (SASP) in pancolitis. The side-effects appeared in 14.2% (5-ASA) and 21% (SASP).


Assuntos
Ácidos Aminossalicílicos/administração & dosagem , Colite Ulcerativa/tratamento farmacológico , Adulto , Idoso , Ácidos Aminossalicílicos/efeitos adversos , Avaliação de Medicamentos , Feminino , Humanos , Masculino , Mesalamina , Pessoa de Meia-Idade , Sulfassalazina/administração & dosagem , Sulfassalazina/efeitos adversos , Fatores de Tempo
14.
Biochem J ; 355(Pt 3): 587-95, 2001 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-11311119

RESUMO

Multidrug resistance caused by P-glycoprotein (P-170) is a phenomenon by which cells exposed to a single drug acquire resistance to other structurally and functionally unrelated drugs. This is a widespread phenomenon described in vivo in the management of infectious as well as non-infectious diseases. Several in vitro models have been developed in order to evaluate physiopathological properties of P-170. Among these are P-170-expressing variants of the human T-lymphoblastoid CEM cell line called VBL100. As a general rule, drug resistance normally results in resistance to apoptosis induction. By contrast, a paradoxical activity is exerted in this cell model by the cytokine tumour necrosis factor-alpha (TNF-alpha), which is capable of inducing apoptosis in P-170-expressing variants better than in wild-type (wt) cells. In the present study we partially address the mechanisms underlying this activity. In fact, the susceptibility of VBL100 cells to TNF-alpha appears to be specifically due to the depolarization of their mitochondrial membrane, a key factor for apoptotic induction. The same was observed with staurosporine, a specific mitochondrion-mediated proapoptotic chemical probe. Conversely, other proapoptotic stimuli, such as Fas/CD95 or the anti-cancer drug etoposide, did induce significant cell death in wild type cells only. Thus, schematically, mitochondrially dependent stimuli appeared to be more effective in VBL100-cell killing, while 'physiological' stimuli showed the opposite behaviour. Importantly, under steady-state conditions, VBL100 cells displayed per se a mitochondrial membrane hyperpolarization that appeared strictly related to their high susceptibility to specific apoptotic stimuli. In conclusion, the study of a well-established cell model such as that represented by the wt/VBL CEM lymphoid cell line seems to suggest that the multidrug resistance phenotype can specifically sensitize cells towards 'unphysiological', mitochondria-associated cell death cascade or, in the same fashion, it could shift cells from type I (mainly plasma membrane-associated) towards type II (mainly mitochondrial membrane-associated) phenotype.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/fisiologia , Apoptose/fisiologia , Mitocôndrias/fisiologia , Citometria de Fluxo , Humanos , Membranas Intracelulares/fisiologia , Potenciais da Membrana , Permeabilidade , Células Tumorais Cultivadas
15.
Development ; 128(23): 4815-27, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11731461

RESUMO

The stem cell leukaemia gene (Scl) encodes a basic helix-loop-helix transcription factor with a pivotal role in both haematopoiesis and endothelial development. During mouse development, Scl is first expressed in extra-embryonic mesoderm, and is required for the generation of all haematopoietic lineages and normal yolk sac angiogenesis. Ectopic expression of Scl during zebrafish development specifies haemangioblast formation from early mesoderm. These results suggest that SCL is essential for establishing the transcriptional programme responsible for the formation of haematopoietic stem cells and have focused attention on the transcriptional regulation of Scl itself. Previous studies have identified a panel of Scl enhancers each of which directed expression to a subdomain of the normal Scl expression pattern. Among them, a 3' enhancer directed expression during development to vascular endothelium and haematopoietic progenitors but not to Ter119(+) erythroid cells. The expression in haematopoietic stem cells, however, remained undetermined. We demonstrate that this 3' enhancer directs lacZ expression in transgenic mice to most foetal and adult long-term repopulating haematopoietic stem cells, and therefore functions as a stem cell enhancer. Consistent with these results, expression in Scl(-/-) embryos of exogenous Scl driven by the stem cell enhancer rescued the formation of early haematopoietic progenitors and also resulted in normal yolk sac angiogenesis. By contrast, erythropoiesis remained markedly deficient in rescued embryos. This observation is consistent with the inactivity of the stem cell enhancer in erythroid cells and reveals an essential role for SCL during erythroid differentiation in vivo.


Assuntos
Proteínas de Ligação a DNA/genética , Elementos Facilitadores Genéticos , Células-Tronco Hematopoéticas/metabolismo , Proteínas Proto-Oncogênicas , Fatores de Transcrição/genética , Proteínas de Peixe-Zebra , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Ensaio de Unidades Formadoras de Colônias , Regulação da Expressão Gênica no Desenvolvimento , Sequências Hélice-Alça-Hélice/genética , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/citologia , Óperon Lac , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Neovascularização Fisiológica/genética , Proteína 1 de Leucemia Linfocítica Aguda de Células T , Saco Vitelino/irrigação sanguínea , Saco Vitelino/embriologia
16.
Biochem Biophys Res Commun ; 279(2): 552-6, 2000 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-11118324

RESUMO

A key role has been proposed for reactive oxygen species (ROS) in chronic obstructive pulmonary disease (COPD). Aim of the present work was to evaluate possible implications of ROS in the integrity and function of the cell type mainly involved in oxygen uptake and delivery to the peripheral tissues: the erythrocyte. Red blood cells (RBCs) were thus collected from blood samples from COPD patients. Furthermore, blood samples from the same patients treated with the antioxidizing drug of widespread use in such disease i.e., N-acetylcysteine (NAC), were also considered. Morphometric and analytical cytology studies were then conducted. We report herein that: (i) alterations of RBC ultrastructure were detectable in RBCs from COPD patients, that (ii) relevant changes of spectrin cytoskeleton and glycophorin expression were also found and that (iii) NAC treatment was capable of significantly counteracting these changes. These results are consistent with a reappraisal of the role of RBCs in this disease.


Assuntos
Acetilcisteína/farmacologia , Eritrócitos/fisiologia , Pneumopatias Obstrutivas/sangue , Idoso , Eritrócitos/efeitos dos fármacos , Eritrócitos/ultraestrutura , Glicoforinas/metabolismo , Humanos , Técnicas In Vitro , Microscopia Eletrônica de Varredura , Espécies Reativas de Oxigênio/fisiologia , Valores de Referência
17.
Genes Dev ; 15(17): 2307-19, 2001 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-11544187

RESUMO

The mammalian Cutl1 gene codes for the CCAAT displacement protein (CDP), which has been implicated as a transcriptional repressor in diverse processes such as terminal differentiation, cell cycle progression, and the control of nuclear matrix attachment regions. To investigate the in vivo function of Cutl1, we have replaced the C-terminal Cut repeat 3 and homeodomain exons with an in-frame lacZ gene by targeted mutagenesis in the mouse. The CDP-lacZ fusion protein is retained in the cytoplasm and fails to repress gene transcription, indicating that the Cutl1(lacZ) allele corresponds to a null mutation. Cutl1 mutant mice on inbred genetic backgrounds are born at Mendelian frequency, but die shortly after birth because of retarded differentiation of the lung epithelia, which indicates an essential role of CDP in lung maturation. A less pronounced delay in lung development allows Cutl1 mutant mice on an outbred background to survive beyond birth. These mice are growth-retarded and develop an abnormal pelage because of disrupted hair follicle morphogenesis. The inner root sheath (IRS) is reduced, and the transcription of Sonic hedgehog and IRS-specific genes is deregulated in Cutl1 mutant hair follicles, consistent with the specific expression of Cutl1 in the progenitors and cell lineages of the IRS. These data implicate CDP in cell-lineage specification during hair follicle morphogenesis, which resembles the role of the related Cut protein in specifying cell fates during Drosophila development.


Assuntos
Células Epiteliais/metabolismo , Pulmão/citologia , Proteínas Nucleares/fisiologia , Proteínas Repressoras/fisiologia , Alelos , Animais , Diferenciação Celular , Citoplasma/metabolismo , DNA Complementar/metabolismo , Drosophila , Éxons , Regulação da Expressão Gênica no Desenvolvimento , Cabelo/embriologia , Proteínas Hedgehog , Proteínas de Homeodomínio , Imuno-Histoquímica , Hibridização In Situ , Pulmão/embriologia , Pulmão/patologia , Camundongos , Modelos Genéticos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Mutação , Estrutura Terciária de Proteína , Fatores de Tempo , Transativadores/metabolismo , Transcrição Gênica , Transfecção , beta-Galactosidase/metabolismo
18.
J Clin Gastroenterol ; 26(3): 222-7, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9600375

RESUMO

Fifty cirrhotic patients with portal hypertension but without colonic or systemic disease underwent lower gastrointestinal endoscopy in order to investigate the effects, if any, of portal hypertension on the colon. Fifty patients without liver or systemic disease, examined by colonoscopy because of irritable bowel syndrome in the same period served as controls. Rectosigmoid varices were observed in 34% of the cirrhotic patients and 2% of the controls. Hemorrhoids were observed in 70% of the cirrhotic patients and 48% of the controls. Multiple vascular-appearing lesions were found in 16% of the cirrhotic patients and 6% of the controls. Nonspecific inflammatory changes were noted in 10% of the cirrhotic patients and 4% of the controls. Simultaneous presence, in the same patient, of rectosigmoid varices, hemorrhoids, multiple vascular-appearing lesions, and nonspecific inflammatory changes, was observed in only five (10%) of the cirrhotic patients. We found polyps in 12% of the cirrhotic patients and 14% of the controls, and a malignant tumor in 4% of the cirrhotic patients. The patients with normal colonoscopic findings were 8% of the cirrhotic patients and 36% of the controls. All patients and controls were followed up for 1 year; there was no gastrointestinal hemorrhage among controls, whereas 34% of the cirrhotic patients had an upper gastrointestinal hemorrhage (88% from esophageal varices, 12% from the stomach) and 4% had a lower gastrointestinal hemorrhage (one from rectosigmoid varices and one from nonspecific inflammatory lesions). Colonic lesions were significantly more frequent in the cirrhotic patients (92%) than in the control group (64%); however, such lesions did not seem specific to the disease and were not statistically correlated with the degree of esophageal varices by Child's grading, the etiology of cirrhosis, or the bleeding risk from the lower gastrointestinal tract.


Assuntos
Doenças do Colo/diagnóstico , Colonoscopia , Hipertensão Portal/diagnóstico , Cirrose Hepática/diagnóstico , Adulto , Idoso , Angiodisplasia/diagnóstico , Angiodisplasia/patologia , Biópsia , Colite/diagnóstico , Colite/patologia , Colo/irrigação sanguínea , Colo/patologia , Doenças do Colo/patologia , Feminino , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/patologia , Hemorroidas/diagnóstico , Hemorroidas/patologia , Humanos , Hipertensão Portal/patologia , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Varizes/diagnóstico , Varizes/patologia
19.
J Clin Microbiol ; 32(1): 232-4, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8126188

RESUMO

Hepatitis C viruses (HCV) present in 110 Italian patients were characterized by genotype-specific PCRs. Among the 65 cases of community-acquired hepatitis, HCV genotype II was dominant (60%), followed by genotypes IV (15%), III (11%), and I (3%). Among the 45 hemophilia-associated cases, the distribution of the four HCV genotypes was markedly different: genotype I was the most prevalent (61%), followed by genotypes II (25%), III (4%), and IV (2%). Double infections were observed in eight patients. Two HCV remained unclassified. For the 45 community-acquired cases from which a liver biopsy was available, genotype II was associated with more severe liver damage than the other types.


Assuntos
Hepatite C/epidemiologia , Hepatite C/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Biópsia , Genótipo , Hemofilia A/complicações , Hepatite C/etiologia , Humanos , Itália/epidemiologia , Fígado/microbiologia , Pessoa de Meia-Idade , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Prevalência
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