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1.
Endoscopy ; 44(6): 556-64, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22638778

RESUMO

BACKGROUND AND STUDY AIM: Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are being used increasingly to treat superficial oropharyngeal and hypopharyngeal carcinomas. The aim of this study was to clarify whether ESD provided better results than EMR for en bloc and complete resection of superficial pharyngeal carcinomas. PATIENTS AND METHODS: A total of 76 superficial pharyngeal carcinomas in 59 consecutively treated patients were included. Patients underwent either conventional EMR (using a transparent cap or strip biopsy) (n = 45 lesions) or ESD (n = 31 lesions) between October 2006 and January 2011. The rates of en bloc resection, complete resection (defined as en bloc resection with tumor-free margins), major complications, and local recurrence were evaluated retrospectively as the therapeutic outcomes. RESULTS: ESD yielded significantly higher rates of both en bloc and complete resection compared with EMR (en bloc 77.4 % [24/31] vs. 37.8 % [17/45], P = 0.0002; complete 54.8 % [17/31] vs. 28.9 % [13/45], P = 0.0379). ESD was more frequently complicated by severe laryngeal edema (4/21 [19.0 %] vs. 1/31 [3.2 %], P = 0.1446) and was also more time-consuming (124.9 ± 65.1 minutes vs. 57.2 ± 69.6 minutes; P = 0.0014). Local recurrence was observed more often after EMR than after ESD (3/45 [6.7 %] vs. 0/31 [0 %]), although this difference did not reach statistical significance (P = 0.2658). CONCLUSIONS: ESD appears to be a superior method of endoscopic resection of superficial pharyngeal carcinomas for achieving both en bloc and complete resection, although these benefits were also associated with a higher incidence of complications and a significantly longer procedure time. Large prospective studies are needed to compare ESD with conventional EMR for superficial pharyngeal carcinomas.


Assuntos
Carcinoma/cirurgia , Endoscopia do Sistema Digestório/métodos , Mucosa/cirurgia , Recidiva Local de Neoplasia/etiologia , Neoplasias Faríngeas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma/patologia , Dissecação/efeitos adversos , Edema/etiologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Laringe , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Neoplasias Faríngeas/patologia , Estudos Retrospectivos , Estatísticas não Paramétricas , Fatores de Tempo
2.
Endoscopy ; 44(2): 122-7, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22271022

RESUMO

BACKGROUND AND STUDY AIM: Endoscopic submucosal dissection (ESD) of undifferentiated-type early gastric cancer (UD-EGC) is technically feasible; however, the long-term clinical outcomes of the procedure have not yet been fully investigated. The aim of our study was to elucidate long-term outcomes of ESD for UD-EGC. PATIENTS AND METHODS: Between September 2003 and October 2009, a total of 153 patients were diagnosed endoscopically as having UD-EGC fulfilling the expanded criteria for ESD. After informed consent was obtained, 101 patients were selected to undergo ESD and 52 to undergo surgical operation. We assessed the clinical outcomes of ESD in 101 consecutive patients with 103 UD-EGC lesions who were undergoing ESD for the first time. The overall mortality and disease-free survival rates after ESD were evaluated as the long-term outcomes. RESULTS: The rates of en bloc and curative resection were 99.0% (102/103) and 82.5% (85/103), respectively. We encountered one patient with nodal metastasis detected by computed tomography before diagnostic ESD, although curative resection of the primary lesion was achieved based on routine histological examination. Among the 78 patients without a past history of malignancy within the previous 5 years in whom curative resection of the primary lesion was achieved, no cases of local recurrence or distant metastasis were observed during follow-up; however, 1 synchronous and 2 metachronous lesions were detected in 2 patients (2.6%) after primary ESD. Thus, estimated over a median follow-up period of 40.0 months (range 19-92 months) and 36.0 months (range 9-92 months), the 3-and 5-year overall mortality rates were 1.9% and 3.9%, respectively, and the 3-and 5-year overall disease-free survival rates were both 96.7%. CONCLUSIONS: Although our single-center retrospective study may be considered to be only preliminary, our data indicate that ESD for UD-EGC may yield good long-term outcomes.


Assuntos
Mucosa Gástrica/cirurgia , Gastroscopia/métodos , Neoplasias Gástricas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Mucosa Gástrica/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Retrospectivos , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Análise de Sobrevida , Taxa de Sobrevida , Resultado do Tratamento
3.
J Microsc ; 234(2): 113-7, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19397739

RESUMO

The goal of specimen preparation for transmission electron microscopy is to obtain high-quality ultra-thin sections with which we can correlate cellular structure to physiological function. In this study, we newly developed a capsule-supporting ring that can be useful for resin embedding of glass-mounted specimens. The present device allowed us to re-embed a semi-thin section on a microscope slide into a resin block not only for efficient ultra-thin sectioning but also for a correlative light and electron microscopy. Similar to epoxy resins for morphological observations, semi-thin sections of low-viscosity hydrophilic resins, such as Lowicryl series, can be re-embedded into the resin, which can be useful for cytochemical gold labelling. A further application of the present device improved flat embedding of cultured cells on glass cover slips for electron microscopy, preserving in situ sub-cellular structures close to their native state. We practically describe the use of capsule-supporting ring and demonstrate representative micrographs as results.


Assuntos
Resinas Epóxi/química , Microscopia Eletrônica , Inclusão em Plástico/instrumentação , Animais , Mucosa Gástrica/ultraestrutura , Células HeLa/ultraestrutura , Humanos , Imuno-Histoquímica , Masculino , Células Parietais Gástricas/ultraestrutura , Ratos , Ratos Wistar
4.
Inflamm Res ; 51(1): 38-43, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11845997

RESUMO

OBJECTIVE: The effects of pretreatment with ONO-4007, a lipid A analog, on cutaneous plasma leakage induced by ONO-4007, lipopolysaccharide (LPS) and inflammatory mediators were investigated. MATERIAL: Male ddY strain mice. TREATMENT: Mice were pretreated with ONO-4007 (up to 6 mg/kg i.p.), 0-24 h prior to plasma leakage study. METHODS: Plasma extravasation was determined by dye leakage. RESULTS: Systemic ONO-4007 (6 mg/kg i. p.) pretreatment for 2 to 12 h inhibited plasma extravasation in the mouse skin elicited by ONO-4007 and LPS. The inhibition was dose-dependent. Plasma leakage induced by platelet-activating factor (PAF), histamine and 5-hydroxytryptamine (5-HT) was also inhibited by ONO-4007 pretreatment. Plasma corticosterone levels increased 2 and 4 h after systemic ONO-4007 (6 mg/kg) administration and returned to the control level 24 h later. Adrenalectomy and metyrapone but not propranolol reversed the inhibition by ONO-4007 pretreatment of LPS-induced plasma leakage. CONCLUSIONS: A single injection of ONO-4007 in mice induced transient tolerance to plasma leakage elicited by LPS, ONO-4007 and inflammatory mediators. Endogenous corticosterone, at least in part, plays a role in the development of tolerance.


Assuntos
Permeabilidade Capilar/efeitos dos fármacos , Lipídeo A/análogos & derivados , Lipídeo A/farmacologia , Glândulas Suprarrenais/fisiologia , Animais , Corticosterona/fisiologia , Lipopolissacarídeos/farmacologia , Masculino , Metirapona/farmacologia , Camundongos
5.
Opt Lett ; 27(1): 46-8, 2002 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-18007711

RESUMO

We have developed a 157-nm coherent light source by two-photon resonant four-wave mixing in Xe, with two tunable single-mode 1-kHz Ti:sapphire laser systems at 768 and 681 nm. This light source has been developed to determine the instrumental function of a vacuum ultraviolet spectrometer and to evaluate optical designs for ultra-line-narrowed F(2) laser lithography. The spectral linewidth of the source was less than 0.008 pm (FWHM), with an average power of 0.6 mW.

6.
Opt Lett ; 27(8): 637-9, 2002 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-18007887

RESUMO

By use of KBe(2)BO(3)F(2) (KBBF) crystal with a size of 10 mmx10 mm x1.2 mm and a special prism-coupling technique (PCT), fourth-harmonic generation of Ti:sapphire laser systems from 200 to 179.4 nm has been achieved. Moreover, with a Ti:sapphire laser with a 50-fs pulse duration and a 1-kHz repetition rate, conversion efficiency as high as 13% from 400 to 200 nm without any surface-loss correction has also been obtained. The data show that with the PCT a KBBF crystal can produce deep-UV coherent light with measurable power output.

7.
Gastroenterology ; 121(6): 1460-72, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11729125

RESUMO

BACKGROUND & AIMS: Tissue recruitment of dendritic cells (DCs) is essential for antigen presentation. This study aimed to examine cellular and molecular mechanisms for DC recruitment to the liver. METHODS: Purified rat DCs were injected into circulation and their traffics were analyzed in normal and Kupffer cell-depleted rats by intravital confocal microscopy and immunohistology. Affinities of DCs to sinusoidal cells were examined by a cell-binding assay. DC precursor recruitment was induced by particulate injection. RESULTS: Both DC precursors and DCs at the antigen-transporting stage could be recruited to the liver, and their majority initially showed a selective binding to Kupffer cells. In the Kupffer cell-depleted rats, DCs could neither be recruited to the liver nor adhere to sinusoidal walls. Pretreatment with varied monosaccharides showed that sugar residues consisting of N-acetylgalactosamine were necessary for this binding. The binding was calcium-dependent, implying the C-type lectin involvement. Furthermore, DCs could endocytose N-acetylgalactosamine polymers in a receptor-specific manner. CONCLUSIONS: The DC-Kupffer cell binding through N-acetylgalactosamine-specific C-type lectin-like receptors is crucial for DC recruitment to the liver. Rat DCs at least partly possess receptors for endocytosis of galactosylated antigens. These DC receptors as well as Kupffer cell lectins are presumably responsible for this binding.


Assuntos
Acetilgalactosamina/metabolismo , Metabolismo dos Carboidratos , Células Dendríticas/fisiologia , Células de Kupffer/fisiologia , Fígado/citologia , Receptores de Superfície Celular/fisiologia , Animais , Movimento Celular/fisiologia , Fenômenos Químicos , Físico-Química , Células Dendríticas/citologia , Endocitose , Polímeros/metabolismo , Ratos , Ratos Endogâmicos , Receptores de Superfície Celular/metabolismo , Células-Tronco/fisiologia
8.
Histochem Cell Biol ; 116(4): 361-9, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11702194

RESUMO

High-pressure freezing/freeze substitution followed by Lowicryl K4M embedding provided an excellent morphology and antigenicity of the gastric glands, as well as the intraluminal fluid contents. Taking advantage of this, we histochemically investigated the secretory dynamics of the zymogenic contents in rat gastric gland, with special references to phospholipase A(2) (PLA(2)) and phospholipase Cgamma1 (PLCgamma1). The combination of immunogold labeling and KMnO4-uranyl acetate-lead citrate staining for zymogenic contents clearly demonstrated the rapid diffusion of PLA(2) molecules from the exocytosed zymogenic contents into the mucinous contents in gastric glandular lumens. In contrast, the exocytosed PLCgamma1 molecules remained within the zymogenic contents in the glandular lumens. These findings indicated the distinction between the exocytosed PLA(2) and PLCgamma1 in their diffusion rate. In addition, the mucinous contents surrounding the exocytosed zymogenic contents were intensely labeled with Griffonia simplicifolia II lectin which specifically recognizes the mucin of mucous neck cells. Interestingly, some of the PLA(2) immunolabeling on the mucinous contents was associated with the apical membranes of gastric epithelial cells, especially that of parietal cells. The secretory dynamics of the zymogenic contents in rat gastric glands, including their interaction with the mucinous contents are discussed.


Assuntos
Precursores Enzimáticos/metabolismo , Mucosa Gástrica/metabolismo , Imuno-Histoquímica/métodos , Isoenzimas/metabolismo , Fosfolipases A/metabolismo , Fosfolipases Tipo C/metabolismo , Resinas Acrílicas , Animais , Exocitose , Substituição ao Congelamento , Congelamento , Mucosa Gástrica/ultraestrutura , Chumbo , Masculino , Microscopia Eletrônica/métodos , Compostos Organometálicos , Fosfolipase C gama , Permanganato de Potássio , Pressão , Ratos , Ratos Wistar , Coloração e Rotulagem/métodos
9.
Histochem Cell Biol ; 115(5): 421-8, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11449890

RESUMO

A monoclonal antibody against insect CALNUC was shown to recognize an 85-kDa nuclear protein specifically in mammalian cells. Amino acid sequencing of the protein purified from rat liver revealed it to be EWS, a prooncoprotein for Ewing sarcomas and related tumors. Using the antibody, distribution of EWS was studied in rat tissues fixed with 4% paraformaldehyde by immunohistochemical methods. On thaw-fixed cryosections or those of perfusion-fixed tissues, almost all cell nuclei showed the specific staining. In immersion-fixed tissues, the staining unexpectedly disappeared in particular tissues (kidney cortex, liver, etc.), although it was recovered by autoclaving the cryosections. Western blotting also demonstrated the ubiquitous expression of EWS in the tissues. In extracts from the liver, the 85-kDa band rapidly disappeared in a Ca(2+)-dependent manner, but never in the testis. The antigen was very labile in kidney homogenates even without Ca2+. Biochemical studies with digoxigenin-labeled EWS showed that the Ca(2+)-dependent disappearance was associated with upward mobility shifts of EWS. These suggested that EWS was ubiquitously expressed in rat tissues, and that the antigen was masked in particular tissues during the immersion fixation.


Assuntos
Anticorpos Monoclonais , Especificidade de Anticorpos/efeitos dos fármacos , Proteínas de Ligação a DNA/imunologia , Substâncias de Crescimento/imunologia , Ribonucleoproteínas/análise , Animais , Cálcio/farmacologia , Proteínas de Ligação ao Cálcio , Epitopos/análise , Epitopos/efeitos dos fármacos , Formaldeído/farmacologia , Ribonucleoproteínas Nucleares Heterogêneas , Humanos , Imuno-Histoquímica , Proteínas de Insetos/imunologia , Masculino , Mamíferos , Camundongos , Proteínas do Tecido Nervoso , Nucleobindinas , Especificidade de Órgãos , Proteína EWS de Ligação a RNA , Ratos , Ratos Wistar , Ribonucleoproteínas/imunologia , Distribuição Tecidual , Fixação de Tecidos/métodos , Células Tumorais Cultivadas
10.
Br J Pharmacol ; 133(2): 237-42, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11350859

RESUMO

Anti-inflammatory effects of cyclic AMP elevating agents were examined in a mouse model of lipopolysaccharide (LPS)-induced microvascular permeability change. Vascular permeability on the back skin was measured by the local accumulation of Pontamine sky blue (PSB) after subcutaneous injection of LPS (400 microg site-1) from Salmonella typhimurium. Dye leakage in the skin was significantly increased 2 h after injection of LPS. This LPS-induced dye leakage was suppressed by phosphodiesterase inhibitors, including pentoxifylline (160 mg kg-1), milrinone (5 - 10 mg kg-1), rolipram (0.5 - 10 mg kg-1) and zaprinast (5 - 10 mg kg-1). The dye leakage was also inhibited by beta-adrenoceptor agonists, including isoproterenol (0.5 - 5 mg kg-1) and salbutamol (0.05 - 5 mg kg-1), an adenylate cyclase activator, forskolin (5 mg kg-1), and a cell permeable cyclic AMP analogue, 8-bromo-cyclic AMP (8-Br-cAMP, 10 mg kg-1). LPS caused a transient increase in serum TNF-alpha level peaking at 1 h after the injection. This increase in serum TNF-alpha was completely blocked by a pretreatment with pentoxifylline (160 mg kg-1), milrinone (5 mg kg-1), rolipram (1 mg kg-1), zaprinast (10 mg kg-1), salbutamol (0.5 mg kg-1), forskolin (1 mg kg-1) and 8-Br-cAMP (10 mg kg-1). LPS caused an increase in serum IL-1alpha level peaking at 3 h after injection. This increase in serum IL-1alpha was not significantly suppressed by the cyclic AMP elevating agents. Our study suggests that cyclic AMP elevating agents attenuate LPS-induced microvascular permeability change by suppressing TNF-alpha up regulation.


Assuntos
Permeabilidade Capilar/efeitos dos fármacos , AMP Cíclico/agonistas , Lipopolissacarídeos/farmacologia , Pele/metabolismo , 8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , Adenilil Ciclases/metabolismo , Agonistas Adrenérgicos beta/farmacologia , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Colforsina/farmacologia , AMP Cíclico/análogos & derivados , Ativadores de Enzimas/farmacologia , Interleucina-1/metabolismo , Masculino , Camundongos , Inibidores de Fosfodiesterase/farmacologia , Salmonella typhimurium , Pele/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo
11.
Gastroenterology ; 120(4): 967-74, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11231950

RESUMO

BACKGROUND & AIMS: Wilson disease is a genetic disorder characterized by the accumulation of copper in the body as a result of a defect of copper excretion from hepatocytes. The intracellular localization of the Wilson disease gene product, ATP7B, was recently identified as the late endosomes. Various mutations have been documented in patients with Wilson disease. The clinical manifestations vary greatly among the patients; however, there is little information on the genotype-phenotype correlation. METHODS: We investigated the distribution of a common ATP7B mutant His1069Gln and a mutant Asp1270Ser by expressing the mutants tagged with green fluorescent protein in Huh7 and HEK293 cells. Intracellular organelles were visualized by fluorescence microscopy. RESULTS: Although the wild-type ATP7B and Asp1270Ser mutant localized in the late endosomes, His1069Gln mutant did not locate in the late endosomes and was degraded by the proteasomes in the cytoplasm. Furthermore, His1069Gln formed aggresomes composed of the degradates and intermediate filaments at the microtubule-organizing center. These aggresomes were similar to Mallory bodies on electron microscopy. CONCLUSIONS: The different protein properties of ATP7B mutants may explain the variety of clinical spectrums in patients with Wilson disease.


Assuntos
Acetilcisteína/análogos & derivados , Adenosina Trifosfatases/genética , Proteínas de Transporte/genética , Proteínas de Transporte de Cátions , Cisteína Endopeptidases/fisiologia , Complexos Multienzimáticos/fisiologia , Mutação/fisiologia , Acetilcisteína/farmacologia , Adenosina Trifosfatases/metabolismo , Proteínas de Transporte/metabolismo , Linhagem Celular , ATPases Transportadoras de Cobre , Cisteína Endopeptidases/efeitos dos fármacos , Cisteína Endopeptidases/ultraestrutura , Citoesqueleto/ultraestrutura , Imunofluorescência , Humanos , Leupeptinas/farmacologia , Microscopia Confocal , Microscopia Eletrônica , Complexos Multienzimáticos/efeitos dos fármacos , Complexos Multienzimáticos/ultraestrutura , Complexo de Endopeptidases do Proteassoma , Distribuição Tecidual
12.
Biochem Biophys Res Commun ; 281(2): 569-75, 2001 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-11181085

RESUMO

The transcriptional coactivator p300, a histone acetyltransferase (HAT), plays key roles in the regulation of cell proliferation and differentiation. p300 is targeted by viral oncoproteins, and mutations of p300, accompanied by inactivation of the second allele, have been reported in certain types of cancers originating in the epithelium. Here, we identified a homozygous p300 deletion of exons 15--18 in the SiHa cervical carcinoma cell line, which results in an in-frame deletion that causes specific loss of the bromodomain, a conserved domain implicated in the regulation of HAT activity. Furthermore, we show that the mutation severely impaired its ability to activate the p21(WAF1/CIP1) promoter in transient reporter assay. These results suggest a critical role for the bromodomain in p300 functions as a tumor-suppressor gene.


Assuntos
Mutação , Proteínas Nucleares/genética , Transativadores/genética , Neoplasias do Colo do Útero/genética , Sequência de Bases , Sítios de Ligação/genética , Western Blotting , Linhagem Celular , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/genética , DNA Complementar/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Células HeLa , Humanos , Células K562 , Luciferases/genética , Luciferases/metabolismo , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Regiões Promotoras Genéticas/genética , Estrutura Terciária de Proteína , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Deleção de Sequência , Transativadores/química , Transativadores/metabolismo , Células Tumorais Cultivadas , Células U937 , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia
13.
J Biol Chem ; 276(13): 9742-8, 2001 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-11133995

RESUMO

The mouse carcinoma cell line SX10 is a hypersensitive mutant to x-rays and bleomycin. An earlier complementation test suggests that SX10 would belong to x-ray-cross complementing group (XRCC) 4. However, in this study, a human XRCC4 expression vector failed to complement the SX10 phenotype. Consistent with the previous report, SX10 showed the same level of DNA-dependent protein kinase activity as the wild-type SR-1. We isolated and analyzed hybrids between SX10 and human diploid fibroblast cells and found that human chromosome 13 conferred the x-ray resistance to the hybrids, suggesting that a candidate gene would be located on this chromosome. Polymerase chain reaction analysis with these hybrids and x-ray-resistant transformants obtained by introducing human chromosomes into SX10 indicated that the mutant was likely to be defective in DNA ligase IV. Sequence analysis of the DNA ligase IV gene confirmed that a defect in SX10 was attributed to a transition of G to A at nucleotide position 1413 of the gene, leading to an amino acid substitution from Trp at residue 471 to a stop codon. Revertant clones (Rev1-3) derived from SX10 showed a restored x-ray resistance; Rev1 reverted to the original nucleotide G at position 1413, whereas Rev2 and Rev3 to C. Transfection of a mouse DNA ligase IV cDNA vector into SX10 restored the resistance to both x-rays and bleomycin. SX10 showed a reduced frequency of chromosomal integration of transfected DNA, but the revertants restored the frequency found in the wild-type cells. These results suggest a possible involvement of DNA ligase IV in the integration event of foreign DNA as well as a crucial role in DNA double-strand break repair.


Assuntos
DNA Ligases/genética , Mutação , Animais , Bleomicina/farmacologia , Southern Blotting , Cromossomos Humanos Par 13 , Códon , DNA/metabolismo , DNA Ligase Dependente de ATP , DNA Complementar/metabolismo , Relação Dose-Resposta à Radiação , Eletroporação , Vetores Genéticos , Humanos , Camundongos , Modelos Genéticos , Fenótipo , Mutação Puntual , Reação em Cadeia da Polimerase , Tolerância a Radiação/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Transfecção , Células Tumorais Cultivadas , Raios X
14.
J Microsc ; 201(Pt 1): 77-83, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11136442

RESUMO

A simple contrast enhancement method is presented for Lowicryl K4M ultrathin sections prepared by high pressure freezing/freeze substitution. The sections were treated with an acidified potassium permanganate oxidizing solution followed by uranyl acetate and lead citrate staining. The method, designated KMnO4-UA/Pb staining, provided a much greater contrast in electron microscopy than conventional UA/Pb staining. In detail, the visibility of plasma membrane was especially improved and the nuclear heterochromatin, mitochondria and cytoplasmic ribosomes showed an adequate increase in electron density. In the mucous cells of rat Brunner's glands, the Golgi cisternae were well defined with the KMnO4-UA/Pb staining. Interestingly, the membranes of the intermediate compartments were moderately reactive to the KMnO4-UA/Pb staining, whereas the cis and the trans compartments were only faintly stained. It should be emphasized that the KMnO4 oxidation following colloidal gold labelling did not cause a remarkable reduction of immunogold labelling and the enhanced contrast helped us to examine the gold particles with high accuracy. This contrast enhancement method is highly promising, with the potential to become a useful tool for histochemical investigation, including immunocytochemistry with the Lowicryl K4M ultrathin sections prepared by high pressure freezing/freeze substitution techniques.


Assuntos
Resinas Acrílicas , Histocitoquímica/métodos , Permanganato de Potássio , Animais , Ácido Cítrico , Duodeno/ultraestrutura , Microanálise por Sonda Eletrônica , Células Epiteliais/ultraestrutura , Congelamento , Aumento da Imagem/métodos , Jejuno/ultraestrutura , Chumbo , Microscopia Eletrônica , Compostos Organometálicos , Oxirredução , Pressão , Ratos , Ratos Wistar , Coloração e Rotulagem , Estômago/ultraestrutura , Inclusão do Tecido
15.
Biol Sci Space ; 15 Suppl: S64-6, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12101352

RESUMO

Several attempts have been made to investigate the effects of microgravity on the growth and function of animal cells. Cellular activation of immune T lymphocytes is greatly affected by microgravity. On the other hand, little is known about the effects of microgravity on B lymphocytes, another major class of immune lymphocytes, their growth or antibody production. Our approach to investigate the human B lymphocytes was to compare cell growth, nutrient consumption, and antibody secretion by a human B cell hybridoma between the cells cultured in space and the ground culture.


Assuntos
Formação de Anticorpos/fisiologia , Linfócitos B/metabolismo , Imunoglobulina M/biossíntese , Voo Espacial , Ausência de Peso , Amônia/metabolismo , Linfócitos B/citologia , Divisão Celular , Linhagem Celular , Glutamina/metabolismo , Humanos
16.
Endocrinology ; 141(11): 4255-61, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11089560

RESUMO

Ghrelin, a novel GH-releasing acylated peptide, was recently isolated from rat stomach. It stimulated the release of GH from the anterior pituitary through the GH secretagogue receptor (GHS-R). Ghrelin messenger RNA and the peptide are present in rat stomach, but its cellular source has yet to be determined. Using two different antibodies against the N- and C-terminal regions of rat ghrelin, we identified ghrelin-producing cells in the gastrointestinal tracts of rats and humans by light and electron microscopic immunohistochemistry and in situ hybridization combined with immunohistochemistry. Ghrelin-immunoreactive cells, which are not enterochromaffin-like cells, D cells, or enterochromaffin cells, accounted for about 20% of the endocrine cell population in rat and human oxyntic glands. Rat ghrelin was present in round, compact, electron-dense granules compatible with those of X/A-like cells whose hormonal product and physiological functions have not previously been clarified. The localization, population, and ultrastructural features of ghrelin-producing cells (Gr cells) indicate that they are X/A-like cells. Ghrelin also was found in enteric endocrine cells of rats and humans. Using two RIAs for the N- and C-terminal regions of ghrelin, we determined its content in the rat gastrointestinal tract. Rat ghrelin was present from the stomach to the colon, with the highest content being in the gastric fundus. Messenger RNAs of ghrelin and GHS-R also were found in these organs. Ghrelin probably functions not only in the control of GH secretion, but also in the regulation of diverse processes of the digestive system. Our findings provide clues to additional, as yet undefined, physiological functions of this novel gastrointestinal hormone.


Assuntos
Células Enteroendócrinas/metabolismo , Hormônios Peptídicos , Peptídeos/análise , Animais , Cromatografia Líquida de Alta Pressão , Fundo Gástrico/química , Grelina , Humanos , Imuno-Histoquímica , Hibridização In Situ , Intestino Grosso/química , Intestino Delgado/química , Jejuno/química , Masculino , Microscopia Imunoeletrônica , Peptídeos/genética , RNA Mensageiro/análise , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
J Vet Med Sci ; 62(8): 897-9, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10993189

RESUMO

With radiography and ultrasound, reversed positioning of the fundus ventriculi and pylorus, a duodenum running on the left side, transposition of the kidneys, and normal thoracic organs were found in a 5-month-old miniature dachshund that presented with anorexia and weight loss. The case was diagnosed as partial heterotaxia. Gross observation revealed partial heterotaxia, polysplenia, abnormal lobulation of the liver, and absence of the greater omentum. These findings were consistent with those observed in asplenia-polysplenia syndrome in humans.


Assuntos
Doenças do Cão/diagnóstico por imagem , Situs Inversus/veterinária , Animais , Cães , Evolução Fatal , Feminino , Radiografia , Situs Inversus/diagnóstico por imagem , Ultrassonografia
18.
Eur J Morphol ; 38(4): 227-31, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10980672

RESUMO

The fine structure of tuft cells in the main excretory duct of rat submandibular gland was investigated using the high pressure freezing and freeze substitution (HPF-FS) method and compared with that seen with both conventional chemical fixation (CF) method and en bloc treatment with ruthenium red. Some MEDs also were subjected to histochemistry for lectins. The apical vesicles and tubules of tuft cells observed by TEM after the HPF-FS method were different in shape from those treated by CF. With the first method, these vesicles and tubules, which may represent sections of a tubular system, appeared more slender and filled with a material of moderate density. A prominent glycocalyx covering the microvillar plasma membrane was observed in tuft cells processed both with the HPF-FS method and with ruthenium red. The surface of microvilli and the tubulo-vesicular structures of these cells exhibited the same soybean agglutinin (SBA) reactivity, suggesting a relationship between them.


Assuntos
Glândula Submandibular/ultraestrutura , Animais , Masculino , Microscopia Eletrônica , Ratos , Ratos Wistar , Fixação de Tecidos/métodos
19.
J Agric Food Chem ; 48(8): 3448-54, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10956132

RESUMO

The cell wall materials (CWMs) from sweetpotato (Ipomoea batatas cv. Kokei 14), cassava (Manihot esculenta), and potato (Solanum tuberosum cv. Danshaku) and commercial sweetpotato fiber as well as their polysaccharide fractions were analyzed for sugar composition by the high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD) method. The separation of arabinose and rhamnose, and xylose and mannose, by this method has been improved using a CarboPac PA 10 column. Pretreatment of the CWMs and cellulose fractions with 12 M H(2)SO(4) was required for complete hydrolysis to occur. Commercial sweetpotato fiber was found to be mainly composed of glucose (88.4%), but small amounts of other sugars were also detected. Among the root crops, sweetpotato CWM had the highest amount of pectin and galacturonic acid. Fucose was detected only in cassava CWM and its hemicellulose fraction, while galactose was present in the highest amount in potato CWM. Among the polysaccharide fractions, it was only in the hemicellulose fraction where significant differences in the sugar composition, especially in the galactose content, were observed among the root crops.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cromatografia por Troca Iônica/métodos , Monossacarídeos/análise , Polissacarídeos/química , Solanaceae/química , Resinas de Troca Aniônica , Parede Celular/química , Fibras na Dieta/análise , Eletroquímica
20.
Eur J Cell Biol ; 79(3): 208-17, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10777113

RESUMO

A mouse monoclonal antibody 12B1 was raised against Golgi fractions from Sf21 insect cells and selected as Golgi-specific by immunostaining of the cells. The antigen was purified from the cells by immunoaffinity chromatography with the monoclonal antibody, and its N-terminal and internal amino acid sequences were determined. Based on the partial amino acid sequences, cDNA encoding the antigen protein was cloned and sequenced. The amino acid sequence deduced from the cDNA nucleotide sequence showed a homology to those of CALNUC family proteins, CALNUC (or nucleobindin, a calcium-binding Golgi protein with DNA-binding activity) and protein NEFA (a cell surface protein with DNA-binding, EF-hand, and acidic domains). The insect protein had two EF-hand loops at the same sites as the mammalian CALNUC family proteins, but had no leucine zipper which the mammalian homologues commonly have. An electron microscopic immunoperoxidase study demonstrated that the insect protein was localized in the cis-Golgi cisternae and cis-Golgi networks. Since this localization is identical to that of mammalian CALNUC, the insect protein was considered to be a homologue of CALNUC rather than that of NEFA. Assays involving proteinase K digestion, sodium carbonate extraction and Triton X-114 extraction revealed that the insect CALNUC-like protein was a soluble protein tightly associated with the luminal surface of Golgi membranes as reported for mammalian CALNUC. The insect protein was also shown to have calcium-binding activity as does mammalian CALNUC. These data verify that the insect protein is CALNUC. The existence of CALNUC in insect cells suggests that CALNUC is an essential calcium-binding Golgi protein in a wide range of the animal kingdom. A phylogenetic tree analysis, however, suggested that NEFA was derived from CALNUC long after the segregation of a mammalian ancestor from an insect ancestor.


Assuntos
Proteínas de Ligação a DNA/biossíntese , Complexo de Golgi/metabolismo , Substâncias de Crescimento/biossíntese , Acetilglucosaminidase/metabolismo , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/metabolismo , Western Blotting , Cálcio/metabolismo , Proteínas de Ligação ao Cálcio , Linhagem Celular , Centrifugação com Gradiente de Concentração , DNA Complementar/metabolismo , Feminino , Imunofluorescência , Imunoglobulina G/metabolismo , Imuno-Histoquímica , Insetos , Manosidases/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica , Dados de Sequência Molecular , Proteínas do Tecido Nervoso , Nucleobindinas , Filogenia , Ligação Proteica , Homologia de Sequência de Aminoácidos , alfa-Manosidase
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