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1.
Nat Commun ; 9(1): 479, 2018 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-29396479

RESUMO

Nano-structured silicon is an attractive alternative anode material to conventional graphite in lithium-ion batteries. However, the anode designs with higher silicon concentrations remain to be commercialized despite recent remarkable progress. One of the most critical issues is the fundamental understanding of the lithium-silicon Coulombic efficiency. Particularly, this is the key to resolve subtle yet accumulatively significant alterations of Coulombic efficiency by various paths of lithium-silicon processes over cycles. Here, we provide quantitative and qualitative insight into how the irreversible behaviors are altered by the processes under amorphous volume changes and hysteretic amorphous-crystalline phase transformations. Repeated latter transformations over cycles, typically featured as a degradation factor, can govern the reversibility behaviors, improving the irreversibility and eventually minimizing cumulative irreversible lithium consumption. This is clearly different from repeated amorphous volume changes with different lithiation depths. The mechanism behind the correlations is elucidated by electrochemical and structural probing.

2.
Clin Exp Dermatol ; 40(7): 786-93, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25786502

RESUMO

BACKGROUND: The aryl hydrocarbon receptor (AhR) recognizes diverse small molecules such as dioxins, tryptophan photoproducts and phytochemicals. It also plays crucial roles in epidermal homeostasis by upregulating epidermal barrier proteins. In preliminary screening, we found that Galactomyces fermentation filtrate (GFF), a cosmetic compound, was capable of activating AhR. AIM: To examine whether GFF upregulates the expression of the filaggrin and loricrin genes, FLG and LOR, in an AhR-dependent manner. METHODS: The activation (cytoplasmic to nuclear translocation) of AhR was confirmed by immunofluorescence study and by upregulation of an AhR-specific marker, cytochrome P450-1A1 (CYP1A1). Gene expression levels were compared by quantitative reverse transcription PCR with or without GFF, interleukin (IL)-4 or IL-13 in normal human keratinocytes. AhR or control knockdown was carried out by transfection with AhR or control small interfering RNA. The protein expression of FLG and LOR was examined by immunohistochemistry using a three-dimensional epidermal equivalent treated with or without GFF or T helper (Th)2 cytokines. RESULTS: GFF induced the nuclear translocation of AhR with significant and dose-dependent upregulation of CYP1A1, FLG and LOR gene expression. The enhancing effects of GFF were abolished in AhR-knockdown keratinocytes. Th2 cytokines decreased expression of genes for FLG and LOR, and this expression was completely restored in the presence of GFF. The downregulated expression of the FLG gene with its restoration by GFF was also evident in the epidermal equivalent. GFF also upregulated the gene expression of genes encoding occludin, claudin-1 and 4, and kallikrein 5 and 7. CONCLUSIONS: Use of GFF is feasible to prevent the Th2-mediated reduction of FLG in an AhR-dependent fashion.


Assuntos
Proteínas de Filamentos Intermediários/metabolismo , Queratinócitos/fisiologia , Receptores de Hidrocarboneto Arílico/metabolismo , Saccharomycetales/metabolismo , Linfócitos T Auxiliares-Indutores/fisiologia , Análise de Variância , Células Cultivadas , Citocromo P-450 CYP1A1/metabolismo , Células Epidérmicas , Fermentação , Proteínas Filagrinas , Humanos , Proteínas de Membrana/metabolismo , Microscopia Confocal , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção , Regulação para Cima
3.
Kyobu Geka ; 63(12): 1028-31, 2010 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-21066841

RESUMO

A male baby was delivered by emergency cesarean section due to fetal distress at 30 weeks of gestational age with a birth weight of 813 g. By fetal echocardiography, the patient had been diagnosed with transposition of great arteries (type 1). Early two-staged arterial switch operation was planned after 34 gestational age avoiding intracranial hemorrhage under cardiopulmonary bypass. At 19 days of life, vegetation was revealed on the pulmonary valve by echocardiography, so he was diagnosed as infectious endocarditis. Cefotaxime and gamma-globulin were given intravenously for 4 weeks. While waiting for the increase in the body weight, desaturation from chronic respiratory distress syndrome was exacerbated. At 8 months old, urgent Senning operation was performed to improve desaturation. The patient was discharged at 20 post operative day. We conclude that Senning operation can be feasible operation in such a complicated case.


Assuntos
Transposição dos Grandes Vasos/cirurgia , Procedimentos Cirúrgicos Cardiovasculares/métodos , Emergências , Endocardite/complicações , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Síndrome do Desconforto Respiratório do Recém-Nascido/complicações
4.
Lett Appl Microbiol ; 49(2): 267-73, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19496929

RESUMO

AIMS: Development of a simple, specific, rapid and inexpensive Dot-ELISA test for early diagnosis of human leptospirosis. METHODS AND RESULTS: Serum samples from 90 patients diagnosed with leptospirosis were analysed by Dot-ELISA test incorporating Glycolipoprotein (GLP) antigen from serovars Copenhageni and Patoc. Results were compared with those obtained with microscopic agglutination test, currently, the gold standard reference serological method. Serum samples from healthy blood bank donors and patients diagnosed with diseases other than leptospirosis were used as negative controls. The specificities of both GLP-based assays were 97.1% and 100% with serum samples from patients with other diseases and with serum samples from healthy control group, respectively. With serum samples from patients with acute leptospirosis, sensitivity was 76.6% with Dot-ELISA Copenhageni and 90.0% with Dot-ELISA Patoc. With serum samples from patients in convalescence, sensitivity was 100% with both GLP-based assays. CONCLUSIONS: This Dot-ELISA provides a candidate antigen for serodiagnosis of leptospirosis during all phases of illness and could be a good alternative method for the early diagnosis of leptospirosis. SIGNIFICANCE AND IMPACT OF THE STUDY: The Dot-ELISA test is simple, specific, rapid and inexpensive. It is suitable for identifying a large number of samples and, hence, reducing the death rate of patients with leptospirosis.


Assuntos
Anticorpos Antibacterianos/sangue , Antígenos de Bactérias , Proteínas de Bactérias , Ensaio de Imunoadsorção Enzimática/métodos , Leptospirose/diagnóstico , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Ensaio de Imunoadsorção Enzimática/economia , Humanos , Imunoglobulina M/sangue , Sensibilidade e Especificidade , Fatores de Tempo
5.
Neuroscience ; 161(3): 743-52, 2009 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-19368896

RESUMO

Calcium acts as an important second messenger in the intracellular signal pathways in a variety of cell functions. Strictly controlled intracellular calcium is required for proper neurite outgrowth of developing neurons. However, the molecular mechanisms of this process are still largely unknown. Neuronal calcium sensor-1 (NCS-1) is a high-affinity and low-capacity calcium binding protein, which is specifically expressed in the nervous system. NCS-1 was distributed throughout the entire region of growth cones located at a distal tip of neurite in cultured chick dorsal root ganglion neurons. In the central domain of the growth cone, however, NCS-1 was distributed in a clustered specific pattern and co-localized with the type 1 inositol 1,4,5-trisphosphate receptor (InsP(3)R1). The pharmacological inhibition of InsP(3) receptors decreased the clustered specific distribution of NCS-1 in the growth cones and inhibited neurite outgrowth but did not change the growth cone morphology. The acute and localized loss of NCS-1 function in the growth cone induced by chromophore-assisted laser inactivation (CALI) resulted in the growth arrest of neurites and lamellipodial and filopodial retractions. These findings suggest that NCS-1 is involved in the regulation of both neurite outgrowth and growth cone morphology. In addition, NCS-1 is functionally linked to InsP(3)R1, which may play an important role in the regulation of neurite outgrowth.


Assuntos
Cones de Crescimento/fisiologia , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Neuritos/fisiologia , Proteínas Sensoras de Cálcio Neuronal/metabolismo , Neuropeptídeos/metabolismo , Animais , Compostos de Boro/administração & dosagem , Cálcio/metabolismo , Bloqueadores dos Canais de Cálcio/administração & dosagem , Células Cultivadas , Embrião de Galinha , Imunofluorescência , Gânglios Espinais/citologia , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/fisiologia , Cones de Crescimento/efeitos dos fármacos , Immunoblotting , Imuno-Histoquímica , Receptores de Inositol 1,4,5-Trifosfato/antagonistas & inibidores , Microscopia Confocal , Microscopia de Fluorescência , Neuritos/efeitos dos fármacos , Pseudópodes/fisiologia , Rianodina/administração & dosagem , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Fatores de Tempo
6.
Braz J Med Biol Res ; 41(2): 126-34, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18235967

RESUMO

We compared the cost-benefit of two algorithms, recently proposed by the Centers for Disease Control and Prevention, USA, with the conventional one, the most appropriate for the diagnosis of hepatitis C virus (HCV) infection in the Brazilian population. Serum samples were obtained from 517 ELISA-positive or -inconclusive blood donors who had returned to Fundação Pró-Sangue/Hemocentro de São Paulo to confirm previous results. Algorithm A was based on signal-to-cut-off (s/co) ratio of ELISA anti-HCV samples that show s/co ratio > or =95% concordance with immunoblot (IB) positivity. For algorithm B, reflex nucleic acid amplification testing by PCR was required for ELISA-positive or -inconclusive samples and IB for PCR-negative samples. For algorithm C, all positive or inconclusive ELISA samples were submitted to IB. We observed a similar rate of positive results with the three algorithms: 287, 287, and 285 for A, B, and C, respectively, and 283 were concordant with one another. Indeterminate results from algorithms A and C were elucidated by PCR (expanded algorithm) which detected two more positive samples. The estimated cost of algorithms A and B was US$21,299.39 and US$32,397.40, respectively, which were 43.5 and 14.0% more economic than C (US$37,673.79). The cost can vary according to the technique used. We conclude that both algorithms A and B are suitable for diagnosing HCV infection in the Brazilian population. Furthermore, algorithm A is the more practical and economical one since it requires supplemental tests for only 54% of the samples. Algorithm B provides early information about the presence of viremia.


Assuntos
Algoritmos , Hepacivirus/genética , Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/sangue , Hepatite C/diagnóstico , RNA Viral/análise , Doadores de Sangue , Brasil , Análise Custo-Benefício , Ensaio de Imunoadsorção Enzimática/economia , Hepatite C/economia , Humanos , Immunoblotting/economia , Reação em Cadeia da Polimerase/economia , Kit de Reagentes para Diagnóstico/economia , Sensibilidade e Especificidade
7.
Braz. j. med. biol. res ; 41(2): 126-134, Feb. 2008. ilus, tab
Artigo em Inglês | LILACS | ID: lil-474770

RESUMO

We compared the cost-benefit of two algorithms, recently proposed by the Centers for Disease Control and Prevention, USA, with the conventional one, the most appropriate for the diagnosis of hepatitis C virus (HCV) infection in the Brazilian population. Serum samples were obtained from 517 ELISA-positive or -inconclusive blood donors who had returned to Fundação Pró-Sangue/Hemocentro de São Paulo to confirm previous results. Algorithm A was based on signal-to-cut-off (s/co) ratio of ELISA anti-HCV samples that show s/co ratio ≥95 percent concordance with immunoblot (IB) positivity. For algorithm B, reflex nucleic acid amplification testing by PCR was required for ELISA-positive or -inconclusive samples and IB for PCR-negative samples. For algorithm C, all positive or inconclusive ELISA samples were submitted to IB. We observed a similar rate of positive results with the three algorithms: 287, 287, and 285 for A, B, and C, respectively, and 283 were concordant with one another. Indeterminate results from algorithms A and C were elucidated by PCR (expanded algorithm) which detected two more positive samples. The estimated cost of algorithms A and B was US$21,299.39 and US$32,397.40, respectively, which were 43.5 and 14.0 percent more economic than C (US$37,673.79). The cost can vary according to the technique used. We conclude that both algorithms A and B are suitable for diagnosing HCV infection in the Brazilian population. Furthermore, algorithm A is the more practical and economical one since it requires supplemental tests for only 54 percent of the samples. Algorithm B provides early information about the presence of viremia.


Assuntos
Humanos , Algoritmos , Hepacivirus/genética , Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/sangue , Hepatite C/diagnóstico , RNA Viral/análise , Doadores de Sangue , Brasil , Análise Custo-Benefício , Ensaio de Imunoadsorção Enzimática/economia , Hepatite C/economia , Immunoblotting/economia , Reação em Cadeia da Polimerase/economia , Kit de Reagentes para Diagnóstico/economia , Sensibilidade e Especificidade
8.
Exp Clin Endocrinol Diabetes ; 114(1): 35-8, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16450315

RESUMO

The occurrence of antinuclear antibody (ANA), rheumatoid factor (RF), antibodies to double-stranded DNA (anti-dsDNA) and to single-stranded DNA (anti-ssDNA) was investigated in 51 patients with autoimmune thyroid diseases (AITD), and in 25 matched control subjects. In comparison with controls, the prevalence of anti-dsDNA was 74.5% in AITD patients (p=0.0001), 82.0% in 39 hyperthyroid Graves' disease (GD) (p=0.0001), and 50.0% in 12 euthyroid Hashimoto's thyroiditis (HT) patients (p=0.0001). The prevalence of anti-ssDNA was 90.1% in AITD (94.8% in GD and 75% in HT; p=0.001). The concentration of both anti-dsDNA and anti-ssDNA were higher (p=0.002) in AITD, in GD (p=0.001), and in HT (p=0.01) patients than in controls. Two patients with AITD were identified as positive for ANA. RF was detected in 4 AITD patients. Positive correlation was noted between anti-dsDNA with T4 (p=0.001), T3 (p=0.002), thyroid peroxidase antibody (anti-TPO) (p=0.0001), and TSH (p=0.001) values but not with thyroglobulin antibody (anti-Tg). Serum anti-ssDNA values were also correlated with T3 (p=0.0001), TSH (p=0.003), and anti-TPO (p=0.0001). However, by using a multiple regression analysis only anti-TPO remained associated with anti-dsDNA and both anti-Tg and anti-TPO with anti-ssDNA values. The predisposition to develop systemic autoimmune disorders is not influenced by thyroid hormones. The elevated prevalence of serum anti-dsDNA and anti-ssDNA in AITD patients points out that we must be aware of the risk for predisposition for the development of other systemic autoimmune diseases.


Assuntos
Anticorpos Antinucleares/sangue , Anticorpos/sangue , DNA de Cadeia Simples/imunologia , DNA/imunologia , Doença de Graves/imunologia , Doença de Hashimoto/imunologia , Adulto , Anticorpos/genética , Anticorpos Antinucleares/genética , Feminino , Doença de Graves/genética , Doença de Hashimoto/genética , Humanos , Masculino , Valores de Referência , Testes de Função Tireóidea
9.
Parasitology ; 128(Pt 5): 483-91, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15180316

RESUMO

The Cytochrome b (Cyt b) gene has proved to be useful for identification and classification of many mammals and plants. In order to evaluate the utility of this gene for discrimination of Leishmania parasites as well as for exploring their phylogenetic relationships, we determined the nucleotide sequences of the Cyt b gene from 13 human-infecting Leishmania species (14 strains) from the New and Old Worlds. The Cyt b genes, approximately 1080 base pairs, were found to be A/T rich, and their 5' terminal-editing regions were highly conserved. The nucleotide sequence variation among them was enough to discriminate parasite species; 245 nucleotide positions were polymorphic and 190 positions were parsimony informative. The phylogenetic relationships based on this gene, showed good agreement with the classification of Lainson & Shaw (1987) except for the inclusion of L. (L.) major in the L. (L.) tropica complex and the placement of L. tarentolae in another genus. These data show that the Cyt b gene is useful for phylogenetic study of Leishmania parasites.


Assuntos
Citocromos b/genética , Leishmania/enzimologia , Leishmania/genética , Sequência de Aminoácidos , Animais , Composição de Bases , Sequência de Bases , Sequência Conservada , Citocromos b/química , DNA de Protozoário/química , DNA de Protozoário/genética , Variação Genética , Humanos , Leishmania/classificação , Leishmaniose/parasitologia , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Alinhamento de Sequência
10.
J Cell Biol ; 155(2): 193-200, 2001 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-11604418

RESUMO

Endophilin 1 is a presynaptically enriched protein which binds the GTPase dynamin and the polyphosphoinositide phosphatase synptojanin. Perturbation of endophilin function in cell-free systems and in a living synapse has implicated endophilin in endocytic vesicle budding (Ringstad, N., H. Gad, P. Low, G. Di Paolo, L. Brodin, O. Shupliakov, and P. De Camilli. 1999. Neuron. 24:143-154; Schmidt, A., M. Wolde, C. Thiele, W. Fest, H. Kratzin, A.V. Podtelejnikov, W. Witke, W.B. Huttner, and H.D. Soling. 1999. Nature. 401:133-141; Gad, H., N. Ringstad, P. Low, O. Kjaerulff, J. Gustafsson, M. Wenk, G. Di Paolo, Y. Nemoto, J. Crun, M.H. Ellisman, et al. 2000. Neuron. 27:301-312). Here, we show that purified endophilin can directly bind and evaginate lipid bilayers into narrow tubules similar in diameter to the neck of a clathrin-coated bud, providing new insight into the mechanisms through which endophilin may participate in membrane deformation and vesicle budding. This property of endophilin is independent of its putative lysophosphatydic acid acyl transferase activity, is mediated by its NH2-terminal region, and requires an amino acid stretch homologous to a corresponding region in amphiphysin, a protein previously shown to have similar effects on lipid bilayers (Takei, K., V.I. Slepnev, V. Haucke, and P. De Camilli. 1999. Nat. Cell Biol. 1:33-39). Endophilin cooligomerizes with dynamin rings on lipid tubules and inhibits dynamin's GTP-dependent vesiculating activity. Endophilin B, a protein with homology to endophilin 1, partially localizes to the Golgi complex and also deforms lipid bilayers into tubules, underscoring a potential role of endophilin family members in diverse tubulovesicular membrane-trafficking events in the cell.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Proteínas de Transporte/metabolismo , Membrana Celular/metabolismo , Membrana Celular/ultraestrutura , Aciltransferases/metabolismo , Sequência de Aminoácidos , Animais , Transporte Biológico , Proteínas de Transporte/química , Tamanho Celular , Dinaminas , GTP Fosfo-Hidrolases/metabolismo , Complexo de Golgi/fisiologia , Humanos , Bicamadas Lipídicas/metabolismo , Substâncias Macromoleculares , Dados de Sequência Molecular , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/metabolismo , Filogenia , Estrutura Terciária de Proteína , Ratos , Homologia de Sequência de Aminoácidos , Vesículas Sinápticas/ultraestrutura
11.
Electrophoresis ; 22(16): 3365-70, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11669511

RESUMO

Exposure of the skin to sunlight results in an increase in the content of epidermal urocanic acid, a key metabolite of L-histidine, and some portions of the metabolite penetrate into the body fluid. S-[2-Carboxy-1-(1H-imidazol-4-yl)ethyl]glutathione (GS(CIE)), an adduct of glutathione and urocanic acid, was proposed to be an origin of a urinary compound, S-[2-carboxy-1-(1 H-imidazol-4-yl)ethyl]-L-cysteine (Cys(CIE)). Various catabolites of Cys(CIE) were also isolated from human urine previously. However, no direct evidence to show the existence of GS(CIE) as a biological material had been found. By using capillary electrophoresis, the glutathione adduct has now been found in the extracts of rat tissues from the kidney, liver, skin and blood when the rat was kept under conditions of sunlight irradiation after the fur on the dorsal skin had been clipped. On the other hand, no or a trace of GS(CIE) was determined in rat tissue extracts when the animal was kept indoor in usual manner. The glutathione adduct was isolated from the kidney extract of the sunlight-irradiated rat using ion-exchangers and high-voltage paper electrophoresis, and determined by fast-atom-bombardment mass spectrometry. These results indicate that GS(CIE) formation actually occurs in the body and that the formation is accelerated by exposing the rat to sunlight irradiation. From these findings, we propose an alternative pathway of histidine metabolism which is initiated by the adduction of urocanic acid to glutathione to form GS(CIE) and terminates with the formation of the urinary compounds via Cys(CIE).


Assuntos
Glutationa/análogos & derivados , Glutationa/análise , Histidina/metabolismo , Imidazóis/análise , Animais , Eletroforese Capilar/métodos , Glutationa/sangue , Humanos , Imidazóis/sangue , Fígado/química , Fígado/efeitos da radiação , Masculino , Estrutura Molecular , Ratos , Ratos Wistar , Pele/química , Pele/efeitos da radiação , Espectrometria de Massas de Bombardeamento Rápido de Átomos/métodos , Luz Solar , Extratos de Tecidos/química
12.
J Dermatol ; 28(9): 475-80, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11603387

RESUMO

In this study, an attempt was made to identify different Leishmania species by polymerase chain reaction (PCR). Fourteen Leishmania strains from stock were tested by PCR and Southern blotting. A pair of primers were employed that anneal to the kinetoplast DNA sequence conserved among subgenus Leishmania. Of the 14 Leishmania strains used in this study, six showed strong bands of approximately 170 bp, and all the positive strains belonged to the species of the subgenus Leishmania viz., Leishmania (Leishmania) garnhami, L. (L.) amazonensis, L. (L.) pifanoi, L. (L.) mexicana, L. (L.) chagasi, and L. (L.) major All the species belonging to the subgenus Viannia used in this study were negative by PCR. These results suggest that the primer pair may be useful for identification of the species belonging to the subgenus Leishmania of the New World as well as to distinguish subgenus Leishmania from subgenus Viannia.


Assuntos
Southern Blotting/métodos , Leishmania/classificação , Leishmania/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Animais , Sequência de Bases , Humanos , Leishmaniose Cutânea/diagnóstico , Dados de Sequência Molecular , Sensibilidade e Especificidade
13.
Plant Cell Physiol ; 42(9): 1017-23, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11577198

RESUMO

Common histidine-to-aspartate (His-->Asp) phosphorelay is a paradigm of signal transduction in both prokaryotes and eukaryotes for the propagation of certain environmental stimuli, in which histidine (His)-kinases play central roles as sensors for environmental signals. For the higher plant, Arabidopsis thaliana, it was recently suggested that the His-kinase (AHK4 / CRE1 / WOL) is a sensor for cytokinins, which are a class of plant hormones important for the regulation of cell division and differentiation. Interestingly, AHK4 is capable of functioning as a cytokinin sensor in the eubacterium, Escherichia coli (Suzuki et al. 2001, Plant Cell Physiol. 42: 107). Here we further show that AHK4 is a primary receptor that directly binds a variety of natural and synthetic cytokinins (e.g. not only N(6)-substituted aminopurines such as isopentenyl-adenine, trans-zeatin, benzyl-adenine, but also diphenylurea derivatives such as thidiazuron), in a highly specific manner (K(d) = 4.55+/-0.48x10(-9) M). AHK4 has a presumed extracellular domain, within which a single amino acid substitution (Thr-301 to Ile) was shown to result in loss of its ability to bind cytokinins. This particular mutation corresponds to the previously reported wol allele (wooden leg) that causes a striking phenotype defective in vascular morphogenesis. Collectively, evidence is presented that AHK4 and its homologues (AHK3 and possibly AHK2) are receptor kinases that can transduce cytokinin signals across the plasma membrane of A. thaliana.


Assuntos
Adenina/análogos & derivados , Arabidopsis/enzimologia , Citocininas/metabolismo , Proteínas Quinases/metabolismo , Adenina/metabolismo , Sequência de Aminoácidos , Arabidopsis/genética , Proteínas de Arabidopsis , Diferenciação Celular , Divisão Celular , Membrana Celular/metabolismo , Histidina Quinase , Isopenteniladenosina/metabolismo , Dados de Sequência Molecular , Proteínas Quinases/genética , Homologia de Sequência de Aminoácidos , Transdução de Sinais , Distribuição Tecidual , Zeatina/metabolismo , beta-Galactosidase/metabolismo
14.
Blood ; 98(6): 1882-8, 2001 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-11535525

RESUMO

Unusual Epstein-Barr virus (EBV) infection into T or natural killer cells plays a pivotal role in the pathogenesis of acute EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH) and chronic active EBV infection (CAEBV). The precise frequency and localization of EBV genome in lymphocyte subpopulations especially within T-cell subpopulations are unclear in these EBV-related disorders. This study analyzed the frequency of EBV-infected cells in circulating lymphocyte subpopulations from 4 patients with acute EBV-HLH and 4 with CAEBV. EBV- encoded small RNA-1 in situ hybridization examination of peripheral blood lymphocytes showed a significantly higher frequency of EBV-infected cells of 1.0% to 13.4% in EBV-HLH and 1.6% to 25.6% in CAEBV, respectively. The patterns of EBV infection in lymphocyte subpopulations were quite different between acute EBV-HLH and CAEBV. EBV infection was predominant in CD8(+) T cells in all EBV-HLH patients, whereas the dominant EBV-infected cell populations were non-CD8(+) lymphocyte subpopulations in CAEBV patients. Phenotypical analysis revealed that EBV-infected cell populations from both EBV-HLH and CAEBV were activated. There was no predominance of any EBV substrain of latent membrane protein-1, EBV-associated nuclear antigen (EBNA)-1, and EBNA-2 genes between the 2 abnormal EBV-associated disorders, and self-limited acute infectious mononucleosis. These results showing differential virus-cell interactions between acute EBV-HLH and CAEBV indicated different pathogenic mechanisms against EBV infection between the 2 EBV-associated diseases, which accounts for the difference in clinical manifestations between the 2 diseases.


Assuntos
Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/virologia , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/isolamento & purificação , Histiocitose de Células não Langerhans/virologia , Células Matadoras Naturais/virologia , Doença Aguda , Linfócitos B/virologia , Pré-Escolar , Doença Crônica , Infecções por Vírus Epstein-Barr/imunologia , Feminino , Genes Virais , Herpesvirus Humano 4/genética , Histiocitose de Células não Langerhans/imunologia , Humanos , Hibridização In Situ , Lactente , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , RNA Viral/análise
15.
Trends Cell Biol ; 11(9): 385-91, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11514193

RESUMO

Clathrin-mediated endocytosis is a vesicular transport event involved in the internalization and recycling of receptors participating in signal transduction events and nutrient import as well as in the reformation of synaptic vesicles. Recent studies in vitro and in living cells have provided a number of new insights into the initial steps of clathrin-coated vesicle formation and the membrane factors involved in this process. The unexpected complexity of these interactions at the cytosol-membrane interface suggests that clathrin-coated vesicle assembly is a highly cooperative process occurring under tight regulatory control. In this review, we focus on the role of membrane proteins and lipids in the nucleation of clathrin-coated pits and provide a hypothetical model for the early steps in clathrin-mediated endocytosis.


Assuntos
Proteínas de Ligação ao Cálcio , Vesículas Revestidas por Clatrina/metabolismo , Endocitose/fisiologia , Transdução de Sinais/fisiologia , Proteínas Adaptadoras de Transporte Vesicular , Animais , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Vesículas Revestidas por Clatrina/ultraestrutura , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Lipídeos de Membrana/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Modelos Biológicos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Sinaptotagminas
16.
J Biol Chem ; 276(44): 41133-42, 2001 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-11498538

RESUMO

We have previously identified synaptojanin 1, a phosphoinositide phosphatase predominantly expressed in the nervous system, and synaptojanin 2, a broadly expressed isoform. Synaptojanin 1 is concentrated in nerve terminals, where it has been implicated in synaptic vesicle recycling and actin function. Synaptojanin 2A is targeted to mitochondria via a PDZ domain-mediated interaction. We have now characterized an alternatively spliced form of synaptojanin 2 that shares several properties with synaptojanin 1. This isoform, synaptojanin 2B, undergoes further alternative splicing to generate synaptojanin 2B1 and 2B2. Both amphiphysin and endophilin, two partners synaptojanin 1, bind synaptojanin 2B2, whereas only amphiphysin binds synaptojanin 2B1. Sequence similar to the endophilin-binding site in synaptojanin 1 is present only in synaptojanin 2B2, and this sequence was capable of affinity purifying endophilin from rat brain. The Sac1 domain of synaptojanin 2 exhibited phosphoinositide phosphatase activity very similar to that of the Sac1 domain of synaptojanin 1. Site-directed mutagenesis further illustrated its functional similarity to the catalytic domain of Sac1 proteins. Antibodies raised against the synaptojanin 2B-specific carboxyl-terminal region identified a 160-kDa protein in brain and testis. Immunofluorescence showed that synaptojanin 2B is localized at nerve terminals in brain and at the spermatid manchette in testis. Active Rac1 GTPase affects the intracellular localization of synaptojanin 2, but not of synaptojanin 1. These results suggest that synaptojanin 2B has a partially overlapping function with synaptojanin 1 in nerve terminals, with additional roles in neurons and other cells including spermatids.


Assuntos
Terminações Nervosas/metabolismo , Proteínas do Tecido Nervoso/química , Monoéster Fosfórico Hidrolases/química , Isoformas de Proteínas/química , Splicing de RNA , Sequência de Aminoácidos , Animais , Sequência de Bases , Cromatografia de Afinidade , Clonagem Molecular , Primers do DNA , GTP Fosfo-Hidrolases/metabolismo , Humanos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Monoéster Fosfórico Hidrolases/genética , Monoéster Fosfórico Hidrolases/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Ratos , Homologia de Sequência de Aminoácidos , Proteínas rac1 de Ligação ao GTP/metabolismo
17.
Eur Urol ; 39(5): 544-50, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11464035

RESUMO

OBJECTIVES: To prospectively assess the efficacy of transurethral holmium (Ho):YAG laser prostatectomy using a side-firing fiber in patients with bladder outlet obstruction due to benign prostatic enlargement (BPE) from the standpoint of urodynamics. METHODS: 32 male patients with BPE aged 53-83 (mean 69.4) years were operated on. All patients, excluding 3 with urinary retention, were evaluated with the International Prostatic Symptom Score (IPSS), Quality of Life (QOL) score and uroflowmetry up to 12 months postoperatively, and a pressure/flow study was performed before and 3 months after the operation. RESULTS: The total IPSS score, QOL score, average and maximum flow rates improved significantly (p<0.0001) at 12 months postoperatively. In the pressure/flow study, detrusor opening pressure, maximum detrusor pressure, detrusor pressure at maximum flow, minimum urethral opening pressure, and Abrams-Griffiths number decreased significantly (p<0.0001, p = 0.0001, p<0.0001, p = 0.0019 and p<0.0001, respectively) 3 months postoperatively. Detrusor instability disappeared in 12 of 17 patients and remained in 2. CONCLUSIONS: Transurethral Ho:YAG laser prostatectomy was found to be effective for the treatment of bladder outlet obstruction due to BPE.


Assuntos
Terapia a Laser/métodos , Hiperplasia Prostática/cirurgia , Ressecção Transuretral da Próstata/métodos , Obstrução do Colo da Bexiga Urinária/cirurgia , Idoso , Idoso de 80 Anos ou mais , Hólmio , Humanos , Terapia a Laser/instrumentação , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Hiperplasia Prostática/complicações , Resultado do Tratamento , Obstrução do Colo da Bexiga Urinária/etiologia , Obstrução do Colo da Bexiga Urinária/fisiopatologia , Urodinâmica/efeitos da radiação
20.
Genomics ; 72(2): 169-79, 2001 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11401430

RESUMO

Here, we report the complete genomic sequence and the characterization of the 311-kb region of 18q21, a candidate tumor suppressor locus containing a region of homozygous deletion in a lung cancer cell line, Ma29. This region contained two known genes, SMAD4 and ME2 (mitochondrial malate oxydoreductase), and two novel genes, D29 (deleted in Ma29 HGMW-approved symbol ELAC1), encoding an evolutionarily conserved protein, and B29 (beside the Ma29 deletion HGMW-approved symbol C18orf3), with no significant homology to any known genes. The deleted DNA segment in Ma29, which was estimated to be 195 kb in size, included all the coding exons of ME2 and D29, but not the coding exons of SMAD4 and B29. The deleted region also included exon 0, a 5'-noncoding exon, of SMAD4, and the expression of SMAD4 was greatly reduced in Ma29 cells. Mutations of SMAD4 and D29 were detected in 1 of 45 lung cancer cell lines examined, while those of ME2 and B29 were not detected, indicating that these four genes are not major targets for 18q21 deletions. The physical and transcriptional map constructed in this study will provide basic information for the identification of a tumor suppressor gene(s) at 18q21 involved in lung carcinogenesis.


Assuntos
Cromossomos Humanos Par 18 , Genes Supressores de Tumor , Neoplasias Pulmonares/genética , Proteínas Supressoras de Tumor , Antígenos CD/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Antígenos CD79 , Mapeamento de Sequências Contíguas , DNA de Neoplasias , Proteínas de Ligação a DNA/genética , Deleção de Genes , Expressão Gênica , Humanos , Dados de Sequência Molecular , Mutação , Proteínas de Neoplasias/genética , Proteínas do Tecido Nervoso/genética , Análise de Sequência de DNA , Proteína Smad4 , Fatores de Transcrição TCF , Transativadores/genética , Fator de Transcrição 4 , Fatores de Transcrição/genética , Transcrição Gênica , Células Tumorais Cultivadas
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