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1.
Am J Perinatol ; 35(2): 170-176, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28854447

RESUMO

INTRODUCTION: Antenatal magnesium sulfate (MgSO4) administration has shown to be effective in minimizing cerebral palsy and severe motor dysfunction at the age of 2 years. The aim of this study is to determine the relationship between the magnesium dose delivered to the mother and the magnesium concentration in the neonates. MATERIALS AND METHODS: A prospective cohort study was conducted on neonates of less than 32 weeks' gestation admitted to the neonatal intensive care unit of University Hospital Complex of Vigo from December 2012 to July 2015. Comparative analysis of magnesium levels between the groups of neonates exposed to MgSO4 and the control group. RESULTS: A total of 118 neonates were included in the study. The mothers of 62 of them had received MgSO4 as a neuroprotective agent. There was a significant correlation between the full dose of MgSO4 received by the mother and the levels of magnesium in the neonate in the first 24 hours of life (r2 = 0.397; p < 0.001). CONCLUSION: The MgSO4 dose received by the mother has a linear relationship with the magnesium levels obtained in neonates.


Assuntos
Recém-Nascido Prematuro/sangue , Sulfato de Magnésio/uso terapêutico , Magnésio/sangue , Fármacos Neuroprotetores/uso terapêutico , Estudos de Casos e Controles , Paralisia Cerebral/prevenção & controle , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Modelos Lineares , Masculino , Transtornos Motores/prevenção & controle , Gravidez , Cuidado Pré-Natal/métodos , Estudos Prospectivos
2.
Ann Hematol ; 92(1): 19-24, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22948274

RESUMO

Morphology is the basis of the diagnosis of myelodysplastic syndromes (MDS). The WHO classification offers prognostic information and helps with the treatment decisions. However, morphological changes are subject to potential inter-observer variance. The aim of our study was to explore the reliability of the 2008 WHO classification of MDS, reviewing 100 samples previously diagnosed with MDS using the 2001 WHO criteria. Specimens were collected from 10 hospitals and were evaluated by 10 morphologists, working in five pairs. Each observer evaluated 20 samples, and each sample was analyzed independently by two morphologists. The second observer was blinded to the clinical and laboratory data, except for the peripheral blood (PB) counts. Nineteen cases were considered as unclassified MDS (MDS-U) by the 2001 WHO classification, but only three remained as MDS-U by the 2008 WHO proposal. Discordance was observed in 26 of the 95 samples considered suitable (27 %). Although there were a high number of observers taking part, the rate of discordance was quite similar among the five pairs. The inter-observer concordance was very good regarding refractory anemia with excess blasts type 1 (RAEB-1) (10 of 12 cases, 84 %), RAEB-2 (nine of 10 cases, 90 %), and also good regarding refractory cytopenia with multilineage dysplasia (37 of 50 cases, 74 %). However, the categories with unilineage dysplasia were not reproducible in most of the cases. The rate of concordance with refractory cytopenia with unilineage dysplasia was 40 % (two of five cases) and 25 % with RA with ring sideroblasts (two of eight). Our results show that the 2008 WHO classification gives a more accurate stratification of MDS but also illustrates the difficulty in diagnosing MDS with unilineage dysplasia.


Assuntos
Exame de Medula Óssea , Medula Óssea/patologia , Síndromes Mielodisplásicas/diagnóstico , Variações Dependentes do Observador , Anemia Refratária com Excesso de Blastos/diagnóstico , Anemia Refratária com Excesso de Blastos/patologia , Biópsia , Linhagem da Célula , Aberrações Cromossômicas , Análise Citogenética , Hematologia , Humanos , Laboratórios Hospitalares , Ensaio de Proficiência Laboratorial , Síndromes Mielodisplásicas/classificação , Síndromes Mielodisplásicas/patologia , Reprodutibilidade dos Testes , Método Simples-Cego , Espanha , Organização Mundial da Saúde
3.
An Pediatr (Barc) ; 70(3): 278-81, 2009 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-19409245

RESUMO

Anti-TNF drugs are used increasingly in several diseases with immune-mediated inflammation, not only in rheumatological conditions, but also in inflammatory bowel disease and psoriasis. Different side effects have been described over the last few years, including the development of psoriasis or psoriasiform exanthemas. These drugs began to be used in paediatrics during the 90's, therefore paediatricians need to be aware of the adverse effects that may occur. We describe here a flexural psoriasis induced by both infliximab and adalimumab in a paediatric patient with Crohn's Disease. To the best of our knowledge, this is the first reported paediatric case of psoriasis triggered by an anti-TNF drug, as well as the first case of psoriasis induced by adalimumab in patients with inflammatory bowel disease.


Assuntos
Anticorpos Monoclonais/efeitos adversos , Doença de Crohn/tratamento farmacológico , Psoríase/induzido quimicamente , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adalimumab , Adolescente , Anticorpos Monoclonais Humanizados , Humanos , Infliximab , Masculino
4.
Neuron ; 28(3): 741-52, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11163263

RESUMO

Cell adhesion molecules (CAMs) implement the process of axon guidance by promoting specific selection and attachment to substrates. We show that, in Drosophila, loss-of-function conditions of either the Neuroglian CAM, the FGF receptor coded by the gene heartless, or the EGF receptor coded by DER display a similar phenotype of abnormal substrate selection and axon guidance by peripheral sensory neurons. Moreover, neuroglian loss-of-function phenotype can be suppressed by the expression of gain-of-function conditions of heartless or DER. The results are consistent with a scenario where the activity of these receptor tyrosine kinases is controlled by Neuroglian at choice points where sensory axons select between alternative substrates for extension.


Assuntos
Axônios/metabolismo , Proteínas de Drosophila , Receptores ErbB/metabolismo , Cones de Crescimento/metabolismo , Neuroglia/metabolismo , Proteínas Tirosina Quinases , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Animais , Axônios/ultraestrutura , Drosophila , Receptores ErbB/genética , Cones de Crescimento/ultraestrutura , Mutação , Neuroglia/citologia , Neurônios Aferentes/citologia , Neurônios Aferentes/metabolismo , Fenótipo , Pupa/citologia , Pupa/genética , Pupa/metabolismo , Receptores de Fatores de Crescimento de Fibroblastos/genética
5.
Neuron ; 20(2): 221-33, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9491984

RESUMO

We have isolated and characterized mutations in Drosophila neurotactin, a gene that encodes a cell adhesion protein widely expressed during neural development. Analysis of both loss and gain of gene function conditions during embryonic and postembryonic development revealed specific requirements for neurotactin during axon outgrowth, fasciculation, and guidance. Furthermore, embryos of some double mutant combinations of neurotactin and other genes encoding adhesion/signaling molecules, including neuroglian, derailed, and kekkon1, displayed phenotypic synergy. This result provides evidence for functional cooperativity in vivo between the adhesion and signaling pathways controlled by neurotactin and the other three genes.


Assuntos
Moléculas de Adesão Celular/genética , Proteínas de Drosophila , Drosophila/genética , Glicoproteínas de Membrana/genética , Neuritos/fisiologia , Proteínas Tirosina Fosfatases , Alelos , Animais , Moléculas de Adesão Celular/metabolismo , Moléculas de Adesão Celular Neuronais/genética , Moléculas de Adesão Celular Neuronais/metabolismo , Sistema Nervoso Central/citologia , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Mutagênese , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Neurônios Aferentes/química , Neurônios Aferentes/enzimologia , Neurônios Aferentes/ultraestrutura , Fenótipo , Receptores Proteína Tirosina Quinases/genética , Receptores Proteína Tirosina Quinases/metabolismo
6.
An Pediatr (Barc) ; 66(2): 184-7, 2007 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-17306106

RESUMO

Childhood obesity is the most frequent nutritional disorder in developed countries and has been described as a global epidemic by the World Health Organization. In children, as in adults, obesity is the most significant risk factor for the development of non-alcoholic fatty liver disease. Therefore, it may become the most frequent chronic liver disease in children. However, pediatric publications on this disorder, which can progress to severe liver disease with risk of mortality, are scarce, with small series and few histological studies. The present article describes an obese adolescent who presented severe steatosis and steatohepatitis, which responded to weight loss with clinical and histological normalization. The risk of obesity comorbidity is increasing significantly in the pediatric population.


Assuntos
Fígado Gorduroso/etiologia , Fígado Gorduroso/terapia , Obesidade/complicações , Redução de Peso , Adolescente , Criança , Humanos , Masculino
7.
Ann Hepatol ; 5(3): 184-6, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17060879

RESUMO

The pregnant woman experiences physiological changes to support fetal growth and development. Particularly the physiological changes of the liver are the results of the increment of estrogens and progesterone during the pregnancy, and also the hemodynamics changes. (hemodilution). Telangiectasia may appear in up to 60% of normal pregnancies. Liver function test (LFT) abnormalities occurs in 3% of the pregnancies, and the Preeclampsia is the most frequent cause. Most of the articles agree that in normal pregnancy the LFT are either normal or slightly increase o decrease but within normal range. Thus, an increase in serum ALT, AST and GGT activities and serum bilirubin and total bile acid concentration during pregnancy may be pathologic and should prompt further evaluation. In the same way the serum albumin levels is significantly low and the serum alkaline phosphatase concentrations are considerably higher and are a normal component of the pregnancy , and if they are within normal range, do not usually indicate the presence of liver disease. The prothrombine time and the partial prothrombine time remain unchanged during pregnancy and serum fibrinogen increase in late pregnancy. Most of the articles related to plasma lipids in pregnancy agree that cholesterol. Triglyceride and lipoprotein increase during pregnancy. Use of gestational age of the pregnancy are the best guide to the differential diagnosis of liver disease in the pregnancy.


Assuntos
Hepatopatias/fisiopatologia , Complicações na Gravidez/fisiopatologia , Colesterol/sangue , Feminino , Humanos , Fígado/metabolismo , Hepatopatias/metabolismo , Testes de Função Hepática , Pré-Eclâmpsia/fisiopatologia , Gravidez , Triglicerídeos/sangue
8.
Leukemia ; 13(10): 1501-5, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10516749

RESUMO

The surface expression of CD79b, using the monoclonal antibody (Mab) CB3-1, on B lymphocytes from normal individuals and patients with B cell chronic lymphocytic leukemia (CLL) has been analyzed using triple-staining cells for flow cytometry. In addition, the clinical significance of CD79b expression in CLL patients and its possible value for the evaluation of minimal residual disease (MRD) was explored. A total of 15 peripheral blood (PB) samples from healthy blood donors, five bone marrow (BM) samples from normal donors and 40 PB samples from CLL untreated patients were included in the study. In addition we studied the expression of CD79b in B lymphocytes from five CLL patients after fludarabine treatment in order to support our method. The expression of CD79b in B lymphocytes from PB was analyzed by flow cytometry, using simultaneous staining with the Mabs CD22, CD79b, CD19 and CD5, CD79b and CD19. Since normal immature bone marrow B cells are CD79b-/dim+ on their surface, in BM samples we used the combination CD45, CD79b and CD19 selecting mature B lymphocytes according to their bright CD45 intensity. Cell acquisition was performed in two consecutive steps using a live gate drawn on SSC/CD19+ cells. For data analysis, the PAINT-A-GATE PRO software (Becton Dickinson) was used. Dilution experiments of CD79b- CLL cells and CD79bdim+ CLL cells with normal PB and BM cells were performed in order to assess the sensitivity level of the technique for detection of CD79b-/dim+residual CLL cells. All B lymphocytes from normal samples showed reactivity for the CD79b antigen. In contrast, CD79b was absent in 18/40 CLL patients (42.5%) and 20/40 CLL cases (50%) exhibited a low CD79b expression. Therefore, CD79b- B lymphocytes would be restricted to the CLL population and thus could be considered a 'tumor phenotype' for monitoring MRD in CLL patients. Dilution experiments indicate that the detection limit with this marker almost reaches the levels obtained by molecular biology methods as the PCR technique. All cases studied after fludarabine presented leukemic cells in their PB or BM samples detected by flow cytometry. Upon comparing the clinical and morphological characteristics of CD79b- and CD79b+ cases, all atypical CLL cases included in the present study were CD79b+ and advanced clinical stage (B and C Binet stage) was most frequently observed in CD79b+ cases than in CD79b- cases.


Assuntos
Antígenos CD/sangue , Leucemia Linfocítica Crônica de Células B/imunologia , Neoplasia Residual/imunologia , Idoso , Antígenos CD79 , Estudos de Casos e Controles , Citometria de Fluxo , Humanos , Imunofenotipagem , Pessoa de Meia-Idade , Neoplasia Residual/diagnóstico
9.
Cir Pediatr ; 18(2): 73-6, 2005 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-16044643

RESUMO

The most generally accepted therapy of choledochal cyst is cystectomy and biliar derivation by laparotomy. Last years, endoscopic papilotomy by ERCP has been a valuable therapeutic alternative, no only a diagnostic method. In this study, we reviewed five pediatric patients operated in our Deparment in last five years for choledochal cyst. The initial therapy was laparotomy (n=4) and endoscopic papilotomy by ERCP (n=1) This one was made in other Hospital. Follow-up has been between one and five years. All patients are living. Four patients who were operated by laparotomy are asyntomatic. Patient who was treated by ERCP needed a new ERCP in first posoperative month. Five years ago, she had a seriuos acute pancreatitis and we decided laparotomy and biliar derivation. Since laparotomy, she had two new episodes of acute pancreatitis and she has needed a new endoscopic dilatation with ballon by ERCP. She has been asyntomatic for four months. In conclusion, we think laparotomy with biliar derivation is safer than ERCP in management of children with choledochal cyst. ERCP must be reserved to emergency situations before laparotomy or after postoperative complications, never as exclusive therapy.


Assuntos
Cisto do Colédoco/cirurgia , Laparoscopia/métodos , Laparotomia/métodos , Pré-Escolar , Feminino , Humanos , Lactente , Masculino
10.
In Vivo ; 9(4): 413-5, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8555443

RESUMO

Since sister chromatid exchange (SCE) relates directly to DNA synthesis which is circadian periodic, this study examines whether a circadian rhythm also characterizes SCEs. In 4-hourly blood samples collected for 48 hours on three diurnally active, nocturnally resting subjects with no family history of chromosome aberrations or instability, a circadian rhythm is demonstrable with an acrophase occurring around 14:45. The circadian amplitude is only of the order of 10% of the MESOR in untreated cultures or in cultures exposed to cefodizime. It remains more or less unchanged in cultures exposed to mitomycin-C, while the MESOR increases by about a factor of 2. In studies of human chromosome aberrations, the circadian rhythmicity of SCE should be taken into consideration.


Assuntos
Cromossomos/genética , Ritmo Circadiano/genética , Troca de Cromátide Irmã/fisiologia , Adulto , Cefotaxima/análogos & derivados , Cefotaxima/farmacologia , Células Cultivadas/efeitos dos fármacos , Cefalosporinas/farmacologia , Feminino , Humanos , Masculino , Mitomicina/farmacologia , Linfócitos T/efeitos dos fármacos
11.
Ginecol Obstet Mex ; 72: 385-93, 2004 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-15526554

RESUMO

BACKGROUND: Preterm labor continues to be the first cause (after congenital malformations) of morbidity and mortality during the perinatal period. One of the markers showing the highest sensitivity to predict preterm labor seems to be fetal fibronectin (fFN) determined in the cervicovaginal secretion. OBJECTIVES: To identify patients at risk of preterm labor based on the presence of fFN in cervicovaginal secretions and to analyze the cost-benefit of medical attention and hospital stay depending on the fFN results. MATERIAL AND METHODS: Four hundred and sixty two patients were admitted in a 6 month period to the Maternal-Fetal Medicine Department. All of them had symptoms of preterm labor. Their gestational ages were between 24 and 34 weeks, the fFN analyses were taken from cervical vaginal secretion. One hundred and fifty eight were fFN positive and 304 were negative. Patients with positive fFN were hospitalized and received specific treatment for preterm labor. The patients with negative fFN were sent home with no medical treatment. In order to calculate the economic impact of the hospital's medical attention we considered the total cost in pesos which included patient's hospital care when admitted with preterm labor symptoms, hospital stay, and neonatal attention. The total costs were compared and analyzed in the two groups. RESULTS: The average cost generated for fFN positive and negative patients was 23,059 and 7,859 pesos, respectively. Approximately 15,200 pesos were saved per patient in this group. Multiplying this amount among patients with negative fFN (n=304), we would have saved 4,620,000 pesos in a 6 month period. Our established medical management did not affect negatively maternal-fetal well being. For statistical purposes of variables the Mann Whitney U, chi square and McNemar's tests were calculated. CONCLUSION: By determining fFN for the diagnosis of preterm labor, we obtained savings of 4,620,000 pesos in a 6 month period avoiding unnecessary treatments and hospital stay in patients with negative fFN. Determination of fFN in cervical vaginal secretion in patients with symptoms of preterm labor showed to have high sensitivity and specificity in predicting preterm labor between 24-34 weeks of gestation, permitting a more rational use of medical management and resources and avoiding unnecessary treatments. The treatment instituted on the basis of an opportune diagnosis in patients with positive fFN showed to prolong weeks of gestation. Although a persistence of morbidity and mortality of prematurity has been reported, these have diminished in comparison with studies previously done in the institution.


Assuntos
Fibronectinas/análise , Glicoproteínas/análise , Trabalho de Parto Prematuro/economia , Líquidos Corporais/química , Colo do Útero , Análise Custo-Benefício , Feminino , Humanos , Gravidez , Estudos Prospectivos , Fatores de Risco
12.
Cir Pediatr ; 17(4): 195-8, 2004 Oct.
Artigo em Espanhol | MEDLINE | ID: mdl-15559207

RESUMO

In pigs, orthotopic liver-intestine transplantation (LITX) has high per operative morbidity and mortality. It is due to hemodynamic, coagulation and metabolism disorders during native liver hepatectomy (total hepatic vascular exclusion) and the postoperative diarrhea secondary to initial dysfunction of the graft and enterectomy of native intestine. To avoid those disturbances and to increase the survival, we have developed a porcine model of auxiliary heterotopic LITX. The allograft was harvested in-bloc, containing the liver, duodenum, pancreas, and jejunum. In the recipient, the liver and intestine were left intact. The allograft was implanted heterotopically, caudal to the native liver. Venous drainage was achieved with anastomosis of donor (D) to recipient (R) infrahepatic cava; and arterialization with anastomosis of D aortic conduit containing the celiac axis and SMA to infra-renal R aorta. The D jejunum was hooked-up to R jejunum. The experiment was performed in 16 animals without intraoperative deaths, hemodynamic stability and no blood requirements. Four animals were left alive 7 days with functioning grafts, suggesting the model viability.


Assuntos
Intestinos/transplante , Transplante de Fígado/métodos , Animais , Suínos
16.
Cell Mol Life Sci ; 55(11): 1386-98, 1999 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-10518988

RESUMO

The peripheral sensory system of the Drosophila adult has been used for the genetic analysis of axon guidance because of its accessibility for experimental manipulation and mutant screens. Wing, leg, antenna, or eye sensory axons are able to pathfind normally under different perturbations, indicating that sensory axon guidance is a highly canalized process. Similarly to other model systems, sensory growth cones seem to use multiple, simultaneous cues for guidance. In addition, sensory axons from peripheral structures seem to be capable of using alternative substrates for pathfinding. Developmental regulation could account for the high stability of axon guidance under experimental and natural perturbation conditions. Despite this flexibility, functional characterization of genes involved in sensory axon guidance is being carried out in situations where there appears to be less system redundancy.


Assuntos
Axônios/ultraestrutura , Drosophila/crescimento & desenvolvimento , Animais , Células Quimiorreceptoras/crescimento & desenvolvimento , Células Quimiorreceptoras/ultraestrutura , Drosophila/fisiologia , Drosophila/ultraestrutura , Mecanorreceptores/crescimento & desenvolvimento , Mecanorreceptores/ultraestrutura , Vias Neurais/crescimento & desenvolvimento , Vias Neurais/ultraestrutura , Neurônios Aferentes/ultraestrutura , Células Fotorreceptoras de Invertebrados/crescimento & desenvolvimento , Células Fotorreceptoras de Invertebrados/ultraestrutura
17.
Development ; 122(9): 2611-21, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8787736

RESUMO

Genetic analysis of the Laminin A (LamA) gene in Drosophila reveals that distinct classes of sensory axons have different requirements for extracellular matrix (ECM) containing laminin A versus epithelial cell surfaces. In the eye-antenna imaginal disc, the nerve from the three simple eyes (ocelli) to the brain is pioneered by a population of transient ocellar neurons whose axons extend on an ECM that covers and connects the disc epithelium and brain. Axons from neighboring mechanosensory (bristle) neurons extend under the ECM in direct contact with the surface of the disc cells, and pioneer a different axon pathway that enters the brain in a different location. In LamA mutants, the ocellar pioneer axons display striking pathfinding defects, while neighboring bristle axons appear normal; the ocellar pioneers usually extend in the proper direction, adhering to the epithelium and sometimes fasciculating with mechanosensory axons, but they invariably fail to reach the brain.


Assuntos
Axônios/fisiologia , Drosophila/crescimento & desenvolvimento , Matriz Extracelular/fisiologia , Laminina/fisiologia , Células Fotorreceptoras de Invertebrados/fisiologia , Animais , Encéfalo/crescimento & desenvolvimento , Diferenciação Celular , Drosophila/genética , Matriz Extracelular/genética , Genes de Insetos , Genótipo , Imuno-Histoquímica , Laminina/genética , Larva/crescimento & desenvolvimento , Microscopia Eletrônica , Mutação , Vias Neurais , Neurônios Aferentes/fisiologia , Células Fotorreceptoras de Invertebrados/citologia , Pupa/crescimento & desenvolvimento
18.
Cell ; 44(2): 303-12, 1986 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-3002632

RESUMO

Hairy-wing (Hw) mutations cause the differentiation of extra chaetes on the cuticle of Drosophila. They are associated with modifications of the achaete-scute complex that consist, in the mutants studied, of insertions of the transposable elements gypsy (Hw1, HwBS) or copia (HwUa). gypsy and copia are inserted in achaete and scute transcribed regions, respectively. Transcription of the insertion-split genes starts at the normal site but terminates within the transposable element sequences. The RNA truncated within gypsy is 5-20 times more abundant than its homolog in wild-type flies. The abundance is reduced in Hw1 revertants and Hw1 stocks carrying su(Hw) mutations. These and other data suggest that the excess function phenotypes of Hw mutations are generated by an increase in achaete or scute transcripts.


Assuntos
Drosophila melanogaster/genética , Animais , Mapeamento Cromossômico , Elementos de DNA Transponíveis , Regulação da Expressão Gênica , Genes , Mutação , Fenótipo , RNA Mensageiro/genética , Sequências Repetitivas de Ácido Nucleico , Transcrição Gênica , Asas de Animais/anatomia & histologia
19.
Development ; 118(2): 325-37, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8223265

RESUMO

In order to dissect the functions of laminin A in vivo, we have undertaken a molecular and genetic characterization of the laminin A subunit (lamA) gene in Drosophila. Sequence analysis predicts a multidomain structure similar to mammalian homologs. We generated a series of complete and partial loss-of-function mutant alleles of the lamA gene; complete loss-of-function mutations lead to late embryonic lethality. Certain combinations of partial loss-of-function lamA alleles give rise to escaper adults, which have rough eyes associated with changes in cell fate and pattern, misshapen legs and defects in wing structure. These phenotypes suggest that laminin A has diverse functions during morphogenesis in Drosophila.


Assuntos
Drosophila/embriologia , Laminina/genética , Fases de Leitura Aberta/genética , Animais , Sequência de Bases , Extremidades/anatomia & histologia , Extremidades/embriologia , Olho/ultraestrutura , Humanos , Laminina/fisiologia , Camundongos , Microscopia Eletrônica de Varredura , Dados de Sequência Molecular , Morfogênese/genética , Morfogênese/fisiologia , Mutagênese Insercional , Fases de Leitura Aberta/fisiologia , Fenótipo , Homologia de Sequência de Aminoácidos , Asas de Animais/embriologia
20.
EMBO J ; 15(23): 6394-9, 1996 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-8978666

RESUMO

Formation of neural precursors in Drosophila is determined by proneural genes. The distinctive pattern of expression of some genes of the achaete-scute complex in the embryonic neuroectoderm has prompted the speculation that they could also function in the specification of neural precursor identity in the CNS. To test this hypothesis, we have analysed the capacity of different proneural proteins to promote the development of a particular CNS precursor, the MP2 precursor. Our results indicate that: (i) all known proneural proteins are similarly able to support the formation of a neural precursor at the position of MP2; (ii) different proneural proteins promote the expression of different characteristics of MP2; and (iii) a totally normal specification of the MP2 fate can only be attained by the proneural genes achaete or scute.


Assuntos
Proteínas de Drosophila , Drosophila melanogaster/embriologia , Embrião não Mamífero/fisiologia , Sistema Nervoso/embriologia , Neurônios/fisiologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/genética , Drosophila melanogaster/genética , Ectoderma/citologia , Ectoderma/fisiologia , Elementos Facilitadores Genéticos , Genes de Insetos , Sistema Nervoso/citologia , Neurônios/citologia , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética
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