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1.
Tech Coloproctol ; 28(1): 71, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916755

RESUMO

BACKGROUNDS: Anastomotic leakage (AL) represents a major complication after rectal low anterior resection (LAR). Transanal drainage tube (TDT) placement offers a potential strategy for AL prevention; however, its efficacy and safety remain contentious. METHODS: A systematic review and meta-analysis were used to evaluate the influence of TDT subsequent to LAR as part of the revision of the surgical site infection prevention guidelines of the Japanese Society of Surgical Infectious Diseases (PROSPERO registration; CRD42023476655). We searched each database, and included randomized controlled trials (RCTs) and observational studies (OBSs) comparing TDT and non-TDT outcomes. The main outcome was AL. Data were independently extracted by three authors and random-effects models were implemented. RESULTS: A total of three RCTs and 18 OBSs were included. RCTs reported no significant difference in AL rate between the TDT and non-TDT groups [relative risk (RR): 0.69, 95% confidence interval (CI) 0.42-1.15]. OBSs reported that TDT reduced AL risk [odds ratio (OR): 0.45, 95% CI 0.31-0.64]. In the subgroup excluding diverting stoma (DS), TDT significantly lowered the AL rate in RCTs (RR: 0.57, 95% CI 0.33-0.99) and OBSs (OR: 0.41, 95% CI 0.27-0.62). Reoperation rates were significantly lower in the TDT without DS groups in both RCTs (RR: 0.26, 95% CI 0.07-0.94) and OBSs (OR: 0.40, 95% CI 0.24-0.66). TDT groups exhibited a higher anastomotic bleeding rate only in RCTs (RR: 4.28, 95% CI 2.14-8.54), while shorter hospital stays were observed in RCTs [standard mean difference (SMD): -0.44, 95% CI -0.65 to -0.23] and OBSs (SMD: -0.54, 95% CI -0.97 to -0.11) compared with the non-TDT group. CONCLUSIONS: A universal TDT placement cannot be recommended for all rectal LAR patients. Some patients may benefit from TDT, such as patients without DS creation. Further investigation is necessary to identify the specific beneficiaries.


Assuntos
Canal Anal , Fístula Anastomótica , Drenagem , Protectomia , Ensaios Clínicos Controlados Aleatórios como Assunto , Reto , Humanos , Fístula Anastomótica/prevenção & controle , Fístula Anastomótica/etiologia , Drenagem/instrumentação , Drenagem/métodos , Protectomia/efeitos adversos , Protectomia/métodos , Reto/cirurgia , Canal Anal/cirurgia , Neoplasias Retais/cirurgia , Resultado do Tratamento , Feminino , Masculino , Estudos Observacionais como Assunto , Pessoa de Meia-Idade
2.
Epidemiol Infect ; 145(14): 2896-2911, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28826420

RESUMO

The purpose of this study was to clarify the association between hand, foot, and mouth disease (HFMD) epidemics and meteorological conditions. We used HFMD surveillance data of all 47 prefectures in Japan from January 2000 to December 2015. Spectral analysis was performed using the maximum entropy method (MEM) for temperature-, relative humidity-, and total rainfall-dependent incidence data. Using MEM-estimated periods, long-term oscillatory trends were calculated using the least squares fitting (LSF) method. The temperature and relative humidity thresholds of HFMD data were estimated from the LSF curves. The average temperature data indicated a lower threshold at 12 °C and a higher threshold at 30 °C for risk of HFMD infection. Maximum and minimum temperature data indicated a lower threshold at 6 °C and a higher threshold at 35 °C, suggesting a need for HFMD control measures at temperatures between 6 and 35 °C. Based on our findings, we recommend the use of maximum and minimum temperatures rather than the average temperature, to estimate the temperature threshold of HFMD infections. The results obtained might aid in the prediction of epidemics and preparation for the effect of climatic changes on HFMD epidemiology.


Assuntos
Epidemias , Doença de Mão, Pé e Boca/epidemiologia , Umidade , Chuva , Temperatura , Criança , Pré-Escolar , Doença de Mão, Pé e Boca/virologia , Humanos , Incidência , Lactente , Recém-Nascido , Japão/epidemiologia , Análise dos Mínimos Quadrados , Estações do Ano
3.
Heredity (Edinb) ; 116(1): 52-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26219230

RESUMO

Many lepidopteran insects exhibit body colour variations, where the high phenotypic diversity observed in the wings and bodies of adults provides opportunities for studying adaptive morphological evolution. In the silkworm Bombyx mori, two genes responsible for moth colour mutation, Bm and Ws, have been mapped to 0.0 and 14.7 cM of the B. mori genetic linkage group 17; however, these genes have not been identified at the molecular level. We performed positional cloning of both genes to elucidate the molecular mechanisms that underlie the moth wing- and body-colour patterns in B. mori. We successfully narrowed down Bm and Ws to ~2-Mb-long and 100-kb-long regions on the same scaffold Bm_scaf33. Gene prediction analysis of this region identified 77 candidate genes in the Bm region, whereas there were no candidate genes in the Ws region. Fluorescence in-situ hybridisation analysis in Bm mutant detected chromosome inversion, which explains why there are no recombination in the corresponding region. The comparative genomic analysis demonstrated that the candidate regions of both genes shared synteny with a region associated with wing- and body-colour variations in other lepidopteran species including Biston betularia and Heliconius butterflies. These results suggest that the genes responsible for wing and body colour in B. mori may be associated with similar genes in other Lepidoptera.


Assuntos
Bombyx/genética , Mapeamento Cromossômico , Ligação Genética , Pigmentação/genética , Asas de Animais , Animais , Genes de Insetos , Hibridização in Situ Fluorescente , Mutação , Fenótipo , Recombinação Genética , Sintenia
4.
Genet Mol Res ; 15(3)2016 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-27706791

RESUMO

Fifteen microsatellite loci were identified in the tetraploid spined loach, Cobitis biwae (Teleostei: Cobitidae). Among these, 14 were polymorphic (5-31 alleles) and showed moderate to high cross-species amplification transferability in four related species, Cobitis matsubarai, Cobitis taenia, Misgurnus anguillicaudatus, and Misgurnus fossilis. The loci, described herein, will be useful for population genetics, phylogeny, parentage analysis, and detection of hybridization among Cobitis species.


Assuntos
Cipriniformes/genética , Loci Gênicos , Repetições de Microssatélites/genética , Tetraploidia , Animais , Especificidade da Espécie
7.
Cytogenet Genome Res ; 140(2-4): 226-40, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23899809

RESUMO

The loach (Misgurnus anguillicaudatus) is an excellent animal model to elucidate biological origin and evolutionary significance of genome duplication and unisexual reproduction because artificially induced and naturally occurring polyploids and parthenogenetic (gynogenetic, androgenetic) animals can be compared. First, we summarize the chromosome manipulation techniques to induce triploids and tetraploids by inhibiting meiotic or mitotic divisions of inseminated eggs, respectively, as well as parthenogenetic animals, obtained after fertilization with genetically inactivated gametes. Then, we review the knowledge on natural polyploid and unisexual lineages found in Misgurnus loaches. A natural diploid-tetraploid complex occurs in wild populations in central China, and these diploid and tetraploid loaches reproduce bisexually. Chinese tetraploids are considered autotetraploid, which may have arisen by doubling of the entire genome of an ancestral diploid, based on cytogenetic results from FISH (fluorescence in situ hybridization) karyotypes and meiotic configurations. In contrast, gynogenetically reproducing clonal diploid lineages have been discovered in a few wild populations in Japan, although most wild-type individuals are bisexually reproducing diploids. Such clonal diploid loaches sometimes produce triploid progeny by accidental incorporation of a sperm nucleus into an unreduced diploid egg, and the resulting triploid generates haploid eggs by meiotic hybridogenesis. Unreduced diploid gametes of clonal loaches are generated by a cytological mechanism, premeiotic endomitosis, which likely occurs in the early (gonium stage) germ cells. Initiation of gynogenetic development is related to a failure of decondensation of the male (sperm) pronucleus in unreduced diploid eggs of a clonal loach. Clonal lineages may have arisen from a past hybrid event between genetically divergent groups, but their exact origins are unknown at present. See also the sister article focusing on plants by Hegarty et al. in this themed issue.


Assuntos
Cipriniformes/genética , Variação Genética , Poliploidia , Reprodução , Animais , Núcleo Celular/genética , Pareamento Cromossômico , Cruzamentos Genéticos , Diploide , Hibridização Genética , Meiose , Cromossomos Sexuais/genética
8.
Clin Exp Immunol ; 173(2): 323-31, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23607908

RESUMO

Eotaxins induce the trafficking of eosinophils to the sites of inflammation via CC chemokine receptor 3 (CCR3). In this study, we investigated eotaxin-3/CC chemokine ligand 26 (CCL26) expression in the inflamed mucosa of patients with inflammatory bowel disease (IBD), and characterized the molecular mechanisms responsible for eotaxin-3 expression in human colonic myofibroblasts. Eotaxin-3 mRNA and protein expression was evaluated by real time-polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA), respectively. Eotaxin-3 mRNA expression was elevated significantly in the active lesions of ulcerative colitis (UC) patients. Significant elevations were also observed in the active lesions of Crohn's disease (CD) patients, but this was significantly lower than that detected in the active UC lesions. There were no significant increases in the inactive lesions of UC or CD patients. Colonic myofibroblasts were identified as a major source of eotaxin-3 in the colonic mucosa, and interleukin (IL)-4 and IL-13 enhanced eotaxin-3 mRNA and protein expression significantly in these cells. There was a significant positive correlation between mucosal eotaxin-3 and IL-4 mRNA expression in the active lesions of IBD patients. The IL-4- and IL-13-induced eotaxin-3 mRNA expression was regulated by the signal transducer and activator of transcription-6 (STAT-6) and suppressor of cytokine signalling (SOCS)1-mediated pathways. Interferon (IFN)-γ acts as a negative regulator on the IL-4- and IL-13-induced eotaxin-3 expression via STAT-1 activation. Eotaxin-3 expression was elevated specifically in the active lesions of IBD, in particular UC. Eotaxin-3 derived from colonic myofibroblasts may play an important role in the pathophysiology of UC.


Assuntos
Quimiocinas CC/metabolismo , Citocinas/imunologia , Doenças Inflamatórias Intestinais/imunologia , Mucosa Intestinal/imunologia , Miofibroblastos/imunologia , Células Th2/imunologia , Células Cultivadas , Quimiocina CCL26 , Quimiocinas CC/genética , Colo/patologia , Humanos , Miofibroblastos/patologia , RNA Mensageiro/análise , Receptores CCR3/metabolismo , Fator de Transcrição STAT6/metabolismo , Transdução de Sinais , Proteína 1 Supressora da Sinalização de Citocina , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Regulação para Cima
9.
Clin Exp Immunol ; 172(3): 410-6, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23600829

RESUMO

Interleukin (IL)-37 is a member of the IL-1 cytokine family. We investigated IL-37b expression in the inflamed mucosa of inflammatory bowel disease (IBD) patients. Furthermore, we analysed IL-37b expression in human colonic epithelial cells. The human colonic epithelial cell line T84 and human colonic subepithelial myofibroblasts (SEMFs) were used. IL-37b expression in the IBD mucosa was evaluated by immunohistochemistry. IL-37b mRNA and protein expression were determined by real time-polymerase chain reaction (PCR) and Western blotting, respectively. IL-37b was not detected in the normal colonic mucosa. In the inflamed mucosa of IBD patients, epithelial IL-37b expression was increased markedly. In ulcerative colitis (UC) and Crohn's disease (CD) patients, IL-37b expression was enhanced in the affected mucosa. In the intestinal epithelial cell line T84, the expression of IL-37b mRNA and protein was enhanced by tumour necrosis factor (TNF)-α. This IL-37b induction by TNF-α was mediated by nuclear factor (NF)-κB and activator protein (AP)-1 activation. Furthermore, IL-37b inhibited TNF-α-induced interferon-γ-inducible protein (IP)-10 expression significantly in human colonic SEMFs. Epithelial IL-37b expression was increased in IBD patients, especially UC patients. IL-37b may be involved in the pathophysiology of IBD as an anti-inflammatory cytokine and an inhibitor of both innate and acquired immune responses.


Assuntos
Doenças Inflamatórias Intestinais/imunologia , Interleucina-1/metabolismo , Imunidade Adaptativa , Células CACO-2 , Estudos de Casos e Controles , Células Cultivadas , Quimiocina CXCL10/genética , Quimiocina CXCL10/metabolismo , Colite Ulcerativa/genética , Colite Ulcerativa/imunologia , Colite Ulcerativa/metabolismo , Colite Ulcerativa/patologia , Doença de Crohn/genética , Doença de Crohn/imunologia , Doença de Crohn/metabolismo , Doença de Crohn/patologia , Expressão Gênica/efeitos dos fármacos , Humanos , Imunidade Inata , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/patologia , Interleucina-1/genética , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Sistema de Sinalização das MAP Quinases , Miofibroblastos/efeitos dos fármacos , Miofibroblastos/imunologia , Miofibroblastos/metabolismo , Miofibroblastos/patologia , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fator de Transcrição AP-1/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
10.
Clin Exp Immunol ; 174(1): 1-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23701206

RESUMO

The regenerating gene (Reg) was isolated originally as a gene specifically over-expressed in regenerating pancreatic islets and constitute a growth factor family. Reg gene product (Reg) is important in the pathophysiology of various human inflammatory diseases. Recently, the possible involvement of human REG in the regeneration of salivary ductal epithelial cells of patients with primary Sjögren's syndrome (SS) was reported. However, the expression of the REG family genes in minor salivary glands (MSG) and the occurrence of anti-REG Iα autoantibodies in SS patients were obscured. In this study, we examined the expression of REG family genes in the MSG of SS and screened anti-REG Iα autoantibodies in SS. The mRNA levels of REG family genes in MSG were quantified using real-time reverse transcription-polymerase chain reaction (RT-PCR) and REG Iα expression in the MSG was analysed by immunohistochemistry. The mRNA level of REG Iα in the MSG of SS patients was significantly higher than that of control. REG Iα protein was expressed highly in SS ductal epithelial cells. Anti-REG Iα autoantibodies in the sera were found in 11% of SS. All the MSG in the anti-REG Iα autoantibody-positive group showed REG Iα expression, whereas only 40% showed REG Iα expression in the anti-REG Iα autoantibody-negative group. The anti-REG Iα autoantibody-positive group showed significantly lower saliva secretion and a higher ratio of grade 4 (by Rubin-Holt) in sialography. These data suggest strongly that autoimmunity to REG Iα might play a role in the degeneration of MSG ductal epithelial cells in primary SS.


Assuntos
Doenças Autoimunes/imunologia , Litostatina/imunologia , Síndrome de Sjogren/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Autoanticorpos/biossíntese , Autoanticorpos/fisiologia , Doenças Autoimunes/complicações , Doenças Autoimunes/genética , Criança , Feminino , Humanos , Interleucina-6/biossíntese , Interleucina-6/genética , Interleucina-8/biossíntese , Interleucina-8/genética , Litostatina/biossíntese , Litostatina/genética , Masculino , Pessoa de Meia-Idade , Glândulas Salivares Menores/imunologia , Glândulas Salivares Menores/metabolismo , Síndrome de Sjogren/complicações , Síndrome de Sjogren/genética , Adulto Jovem
12.
Eur J Gynaecol Oncol ; 33(4): 353-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23091889

RESUMO

OBJECTIVE: Radical hysterectomy (RH) is a standard treatment for locally advanced non-squamous cell carcinoma (N-SCC) of the uterine cervix, but there have been no reports on whether neoadjuvant chemotherapy (NAC) followed by radical hysterectomy could improve the outcome of patients with this disease. MATERIALS AND METHODS: This multicenter retrospective study enrolled 77 patients with Stage IB2 to IIB N-SCC of the uterine cervix. Of these, 27 patients were treated with NAC prior to radical hysterectomy (NAC group) and 50 with RH alone (RH group). The two-year recurrence-free survival (RFS) rate, progression-free survival (PFS), and overall survival (OS) were compared between the two groups. Clinical parameters such as clinical stage, histological type, and postoperative treatment were also examined between the groups. RESULTS: While the two-year RFS rates were 81.5% and 70.0% in NAC and RH groups, respectively (p = 0.27) and the median PFS was 51 months and 35 months in NAC and RH groups, respectively (p = 0.35), the median OS was 58 months and 48 months in NAC and RH groups, respectively, which was significant (p = 0.0014). The median OS of patients with mucinous adenocarcinoma in NAC group was significantly higher than that in RH group: 58 months versus 37 months (p = 0.03). CONCLUSION: NAC prior to RH may offer the prognostic advantage of patients with locally advanced N-SCC of the uterine cervix, especially mucinous adenocarcinoma.


Assuntos
Histerectomia , Neoplasias do Colo do Útero/terapia , Adulto , Idoso , Quimioterapia Adjuvante , Intervalo Livre de Doença , Feminino , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estudos Retrospectivos , Neoplasias do Colo do Útero/mortalidade
13.
Mymensingh Med J ; 19(1): 110-5, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20046182

RESUMO

Positron emission tomography (PET) is widely used in the fields of clinical and basic medicine. The PET device utilizes coincidence logic to detect annihilation photons emitted from positrons and estimates physiological functions of human organs in vivo. Radiopharmaceutical 18F- fluorodeoxyglucose (FDG), an analogue of glucose, is trapped metabolically in cells after being administered into the body, and can be substantially used for evaluating physiological and biochemical functions in vivo. Here, we attempted to describe the basics of PET as well as to apply the technique together with 18F-FDG as a tracer for evaluating organ glucose metabolism induced by exercise. Three-dimensional (3D) FDG-PET was applied to normal volunteers who performed exercise to evaluate whole-body glucose metabolism. Regions of interest analysis were drawn on visually defined regions (i.e., lower limbs, thigh, liver, intestine, brain, heart, etc.) to determine radioactivity distribution. FDG-PET clearly showed the recruitment of energy resources from abdominal organs to lower limb skeletal muscles to balance energy expenditures. The results suggested that 3D FDG-PET can be applied as an imaging tool to physical medicine.


Assuntos
Glicemia/metabolismo , Metabolismo Energético/fisiologia , Tomografia por Emissão de Pósitrons , Corrida/fisiologia , Imagem Corporal Total , Adolescente , Adulto , Fluordesoxiglucose F18 , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Descanso/fisiologia , Adulto Jovem
14.
J Cell Biol ; 120(5): 1147-57, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8382206

RESUMO

The Ca2+ pump in the plasma membrane plays a key role in the fine control of the cytoplasmic free Ca2+ concentration. In the present study, its subcellular localization was examined with immunocytochemical techniques using a specific antibody generated against the erythrocyte membrane Ca2+ pump ATPase. By immunofluorescence microscopy of cultured cells, the labeling with the antibody was seen as numerous small dots, often distributed in linear arrays or along cell edges. Immunogold EM of cryosections revealed that the dots correspond to caveolae, or smooth invaginations of the plasma membrane. The same technique applied to mouse tissues in vivo showed that the Ca2+ pump is similarly localized in caveolae of endothelial cells, smooth muscle cells, cardiac muscle cells, epidermal keratinocytes and mesothelial cells. By quantitative analysis of the immunogold labeling, the Ca2+ pump in capillary endothelial cells and visceral smooth muscle cells was found to be concentrated 18-25-fold in the caveolar membrane compared with the noncaveolar portion of the plasma membrane. In renal tubular and small intestinal epithelial cells, which have been known to contain the Ca2+ pump but do not have many caveolae, most of the labeling was randomly distributed in the basolateral plasma membrane, although caveolae were also positively labeled. The results demonstrate that the caveolae in various cells has the plasmalemmal Ca2+ pump as a common constituent. In conjunction with our recent finding that an inositol 1,4,5-trisphosphate receptor-like protein exists in the caveolae (Fujimoto, T., S. Nakade, A. Miyawaki, K. Mikoshiba, and K. Ogawa. 1992. J. Cell Biol. 119:1507-1513), it is inferred that the smooth plasmalemmal invagination is an apparatus specialized for Ca2+ intake and extrusion from the cytoplasm.


Assuntos
Canais de Cálcio , ATPases Transportadoras de Cálcio/metabolismo , Membrana Celular/enzimologia , Receptores Citoplasmáticos e Nucleares , Células 3T3 , Animais , Especificidade de Anticorpos , ATPases Transportadoras de Cálcio/imunologia , Membrana Celular/ultraestrutura , Polaridade Celular , Células Cultivadas , Endotélio Vascular/ultraestrutura , Epitélio/ultraestrutura , Membrana Eritrocítica/enzimologia , Fibroblastos/ultraestrutura , Humanos , Imuno-Histoquímica , Receptores de Inositol 1,4,5-Trifosfato , Túbulos Renais Distais/ultraestrutura , Camundongos , Receptores de Superfície Celular/metabolismo , Suínos
15.
J Cell Biol ; 103(6 Pt 2): 2775-86, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3539944

RESUMO

It is currently believed that the intermediate filaments of endothelial cells contain vimentin subunits exclusively. This inference, however, is derived from studies of only a few types of endothelial cells. By double indirect immunofluorescence and immunoelectron microscopy, we have now examined the endothelial cells of the micro- and macrovasculature of a variety of tissues and organs of adult chicken in vivo for their content of desmin and vimentin. Endothelial cells of the peritubular capillary in the renal cortex, the hepatic sinusoid, and the splenic sinusoid were found to contain only desmin; those of the exocrine pancreas capillary contained both desmin and vimentin; and the endothelial cells of the macrovasculatures and of all the other microvasculatures examined, including the vasa recta of the renal medulla, contained only vimentin. Such heterogeneity suggests that different types of adult chicken endothelial cells may have different embryological origins. To the extent that desmin and vimentin intermediate filaments may be functionally distinct, these results also suggest that different capillary endothelial cells may have different functional properties.


Assuntos
Citoesqueleto/ultraestrutura , Desmina/metabolismo , Endotélio/ultraestrutura , Filamentos Intermediários/ultraestrutura , Vimentina/metabolismo , Animais , Artérias/ultraestrutura , Encéfalo/irrigação sanguínea , Capilares/ultraestrutura , Galinhas , Vasos Coronários/ultraestrutura , Endotélio/metabolismo , Imunofluorescência , Filamentos Intermediários/metabolismo , Córtex Renal/irrigação sanguínea , Medula Renal/irrigação sanguínea , Fígado/irrigação sanguínea , Pâncreas/irrigação sanguínea , Baço/irrigação sanguínea , Veias/ultraestrutura
16.
J Cell Biol ; 119(6): 1507-13, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1334960

RESUMO

Activation of various receptors by extracellular ligands induces an influx of Ca2+ through the plasma membrane, but its molecular mechanism remains elusive and seems variable in different cell types. In the present study, we utilized mAbs generated against the cerebellar type I inositol 1,4,5-trisphosphate (InsP3) receptor and performed immunocytochemical and immunochemical experiments to examine its localization in several non-neuronal cells. By immunogold electron microscopy of ultrathin frozen sections as well as permeabilized tissue specimens, we found that a mAb to the type I InsP3 receptor (mAb 4C11) labels the plasma membrane of the endothelium, smooth muscle cell and keratinocyte in vivo. Interestingly, the labeling with the antibody was confined to caveolae, smooth vesicular inpocketings of the plasma membrane. The reactive protein, with an M(r) of 240,000 by SDS-PAGE, could be biotinylated with a membrane-impermeable reagent, sulfo-NHS-biotin, in intact cultured endothelial cells, and recovered by streptavidin-agarose beads, which result further confirmed its presence on the cell surface. The present findings indicate that a protein structurally homologous to the type I InsP3 receptor is localized in the caveolar structure of the plasma membrane and might be involved in the Ca2+ influx.


Assuntos
Canais de Cálcio , Membrana Celular/química , Receptores de Superfície Celular/isolamento & purificação , Receptores Citoplasmáticos e Nucleares , Animais , Anticorpos Monoclonais , Biotina , Western Blotting , Membrana Celular/imunologia , Membrana Celular/ultraestrutura , Endotélio Vascular/química , Endotélio Vascular/imunologia , Endotélio Vascular/ultraestrutura , Epiderme/química , Epiderme/imunologia , Epiderme/ultraestrutura , Imuno-Histoquímica , Receptores de Inositol 1,4,5-Trifosfato , Queratinócitos/química , Queratinócitos/imunologia , Queratinócitos/ultraestrutura , Camundongos , Camundongos Endogâmicos , Microscopia Imunoeletrônica , Músculo Liso/química , Músculo Liso/imunologia , Músculo Liso/ultraestrutura , Receptores de Superfície Celular/imunologia
17.
J Cell Biol ; 152(5): 1079-85, 2001 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-11238462

RESUMO

Caveolin-1 and -2 constitute a framework of caveolae in nonmuscle cells. In the present study, we showed that caveolin-2, especially its beta isoform, is targeted to the surface of lipid droplets (LD) by immunofluorescence and immunoelectron microscopy, and by subcellular fractionation. Brefeldin A treatment induced further accumulation of caveolin-2 along with caveolin-1 in LD. Analysis of mouse caveolin-2 deletion mutants revealed that the central hydrophobic domain (residues 87-119) and the NH(2)-terminal (residues 70-86) and COOH-terminal (residues 120-150) hydrophilic domains are all necessary for the localization in LD. The NH(2)- and COOH-terminal domains appeared to be related to membrane binding and exit from ER, respectively, implying that caveolin-2 is synthesized and transported to LD as a membrane protein. In conjunction with recent findings that LD contain unesterified cholesterol and raft proteins, the result implies that the LD surface may function as a membrane domain. It also suggests that LD is related to trafficking of lipid molecules mediated by caveolins.


Assuntos
Caveolinas/metabolismo , Metabolismo dos Lipídeos , Microdomínios da Membrana/química , Microdomínios da Membrana/metabolismo , Organelas/química , Organelas/metabolismo , Animais , Transporte Biológico/efeitos dos fármacos , Brefeldina A/farmacologia , Caveolina 1 , Caveolina 2 , Caveolinas/química , Caveolinas/genética , Linhagem Celular , Retículo Endoplasmático/metabolismo , Fibroblastos , Imunofluorescência , Humanos , Camundongos , Microscopia Imunoeletrônica , Organelas/efeitos dos fármacos , Organelas/ultraestrutura , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Sinais Direcionadores de Proteínas , Transporte Proteico/efeitos dos fármacos , Ratos , Deleção de Sequência/genética
18.
J Cell Biol ; 143(1): 95-106, 1998 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-9763423

RESUMO

Cell polarity is fundamental to differentiation and function of most cells. Studies in mammalian epithelial cells have revealed that the establishment and maintenance of cell polarity depends upon cell adhesion, signaling networks, the cytoskeleton, and protein transport. Atypical protein kinase C (PKC) isotypes PKCzeta and PKClambda have been implicated in signaling through lipid metabolites including phosphatidylinositol 3-phosphates, but their physiological role remains elusive. In the present study we report the identification of a protein, ASIP (atypical PKC isotype-specific interacting protein), that binds to aPKCs, and show that it colocalizes with PKClambda to the cell junctional complex in cultured epithelial MDCKII cells and rat intestinal epithelia. In addition, immunoelectron microscopy revealed that ASIP localizes to tight junctions in intestinal epithelial cells. Furthermore, ASIP shows significant sequence similarity to Caenorhabditis elegans PAR-3. PAR-3 protein is localized to the anterior periphery of the one-cell embryo, and is required for the establishment of cell polarity in early embryos. ASIP and PAR-3 share three PDZ domains, and can both bind to aPKCs. Taken together, our results suggest a role for a protein complex containing ASIP and aPKC in the establishment and/or maintenance of epithelial cell polarity. The evolutionary conservation of the protein complex and its asymmetric distribution in polarized cells from worm embryo to mammalian-differentiated cells may mean that the complex functions generally in the organization of cellular asymmetry.


Assuntos
Proteínas de Caenorhabditis elegans , Proteínas de Transporte , Moléculas de Adesão Celular , Polaridade Celular/fisiologia , Células Epiteliais/fisiologia , Proteínas de Helminto/metabolismo , Mucosa Intestinal/fisiologia , Proteína Quinase C/metabolismo , Junções Íntimas/fisiologia , Células 3T3 , Proteínas Adaptadoras de Transdução de Sinal , Sequência de Aminoácidos , Animais , Caenorhabditis elegans/fisiologia , Proteínas de Ciclo Celular , Linhagem Celular , Cães , Células Epiteliais/ultraestrutura , Proteínas de Helminto/química , Proteínas de Helminto/genética , Mucosa Intestinal/ultraestrutura , Isoenzimas , Mamíferos , Camundongos , Dados de Sequência Molecular , Proteínas Serina-Treonina Quinases , RNA Mensageiro/biossíntese , Ratos , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Junções Íntimas/ultraestrutura , Transcrição Gênica , Transfecção
19.
J Cell Biol ; 141(2): 397-408, 1998 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-9548718

RESUMO

Occludin is the only known integral membrane protein of tight junctions (TJs), and is now believed to be directly involved in the barrier and fence functions of TJs. Occludin-deficient embryonic stem (ES) cells were generated by targeted disruption of both alleles of the occludin gene. When these cells were subjected to suspension culture, they aggregated to form simple, and then cystic embryoid bodies (EBs) with the same time course as EB formation from wild-type ES cells. Immunofluorescence microscopy and ultrathin section electron microscopy revealed that polarized epithelial (visceral endoderm-like) cells were differentiated to delineate EBs not only from wild-type but also from occludin-deficient ES cells. Freeze fracture analyses indicated no significant differences in number or morphology of TJ strands between wild-type and occludin-deficient epithelial cells. Furthermore, zonula occludens (ZO)-1, a TJ-associated peripheral membrane protein, was still exclusively concentrated at TJ in occludin-deficient epithelial cells. In good agreement with these morphological observations, TJ in occludin-deficient epithelial cells functioned as a primary barrier to the diffusion of a low molecular mass tracer through the paracellular pathway. These findings indicate that there are as yet unidentified TJ integral membrane protein(s) which can form strand structures, recruit ZO-1, and function as a barrier without occludin.


Assuntos
Células Epiteliais/citologia , Proteínas de Membrana/fisiologia , Células-Tronco/citologia , Junções Íntimas/fisiologia , Animais , Biotina/análogos & derivados , Diferenciação Celular , Permeabilidade da Membrana Celular , Polaridade Celular , Células Cultivadas , Técnica de Fratura por Congelamento , Marcação de Genes , Proteínas de Membrana/análise , Camundongos , Ocludina , Fosfoproteínas/análise , Succinimidas , Junções Íntimas/química , Junções Íntimas/ultraestrutura , Proteína da Zônula de Oclusão-1
20.
J Cell Biol ; 139(2): 517-28, 1997 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-9334353

RESUMO

A novel actin filament (F-actin)-binding protein with a molecular mass of approximately 205 kD (p205), which was concentrated at cadherin-based cell-to-cell adherens junction (AJ), was isolated and characterized. p205 was purified from rat brain and its cDNA was cloned from a rat brain cDNA library. p205 was a protein of 1,829 amino acids (aa) with a calculated molecular mass of 207,667 kD. p205 had one F-actin-binding domain at 1,631-1,829 aa residues and one PDZ domain at 1,016- 1,100 aa residues, a domain known to interact with transmembrane proteins. p205 was copurified from rat brain with another protein with a molecular mass of 190 kD (p190). p190 was a protein of 1,663 aa with a calculated molecular mass of 188,971 kD. p190 was a splicing variant of p205 having one PDZ domain at 1,009-1,093 aa residues but lacking the F-actin-binding domain. Homology search analysis revealed that the aa sequence of p190 showed 90% identity over the entire sequence with the product of the AF-6 gene, which was found to be fused to the ALL-1 gene, known to be involved in acute leukemia. p190 is likely to be a rat counterpart of human AF-6 protein. p205 bound along the sides of F-actin but hardly showed the F-actin-cross-linking activity. Northern and Western blot analyses showed that p205 was ubiquitously expressed in all the rat tissues examined, whereas p190 was specifically expressed in brain. Immunofluorescence and immunoelectron microscopic studies revealed that p205 was concentrated at cadherin-based cell-to-cell AJ of various tissues. We named p205 l-afadin (a large splicing variant of AF-6 protein localized at adherens junction) and p190 s-afadin (a small splicing variant of l-afadin). These results suggest that l-afadin serves as a linker of the actin cytoskeleton to the plasma membrane at cell-to-cell AJ.


Assuntos
Encéfalo/metabolismo , Adesão Celular , Junções Intercelulares/metabolismo , Proteínas dos Microfilamentos/análise , Proteínas dos Microfilamentos/biossíntese , Actinas/metabolismo , Sequência de Aminoácidos , Animais , Anticorpos , Química Encefálica , Caderinas/análise , Mapeamento Cromossômico , Clonagem Molecular , DNA Complementar , Feto , Humanos , Junções Intercelulares/ultraestrutura , Cinesinas , Camundongos , Proteínas dos Microfilamentos/química , Dados de Sequência Molecular , Peso Molecular , Miosinas , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/imunologia , Mapeamento de Peptídeos , Ratos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Baço/metabolismo , Vinculina/análise
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