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1.
Rev Sci Instrum ; 87(1): 013704, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26827325

RESUMO

We present a new compact instrument designed for scanning transmission X-ray microscopy. It has piezo-driven linear stages, making it small and light. Optical components from the virtual source point to the detector are located on a single optical table, resulting in a portable instrument that can be operated at a general-purpose spectroscopy beamline without requiring any major reconstruction. Careful consideration has been given to solving the vibration problem common to high-resolution microscopy, so as not to affect the spatial resolution determined by the Fresnel zone plate. Results on bacteriogenic iron oxides, single particle aerosols, and rare-earth permanent magnets are presented as examples of its performance under diverse applications.

2.
J Phys Chem B ; 111(35): 10365-72, 2007 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-17696390

RESUMO

Interchain interaction, i.e., pi-pi stacking, can benefit the carrier transport in conjugated regio-regular poly(3-hexylthiophene) (P3HT) thin films. However, the existence of the insulating side hexyl chains in the surface region may be detrimental to the charge transfer between the polymer backbone and overlayer molecules. The control of the molecular orientation in the surface region is expected to alter the distribution of the pi electron density at the surface to solve such problems, which can be achieved by controlling the solvent removal rate during solidification. The evidence that the pi-electron density distribution at the outermost surface can be controlled is demonstrated by the investigation using the powerful combination of near edge X-ray absorption fine structure spectroscopy, ultraviolet photoelectron spectroscopy, and the most surface-sensitive technique: Penning ionization electron spectroscopy. From the spectroscopic studies, it can be deduced that the slower removal rate of the solvent makes the polymer chains even at the surface have sufficient time to adopt a more nearly equilibrium structure with edge-on conformation. Thus, the side hexyl chains extend outside the surface, which buries the pi-electron density contributed from the polymer backbone. Contrarily, the quench of obtaining a thermo-equilibrium structure in the surface region due to the faster removal of the solvent residual can lead to the surface chain conformation without persisting to the strong bulk orientation preference. Therefore, the face-on conformation of the polymer chain at the surface of thin films coated with high spin coating speed facilitate the electron density of the polymer backbone exposed outside the surface. Finally, thickness dependence of the surface electronic structure of P3HT thin films is also discussed.

3.
Kyobu Geka ; 60(7): 599-601, 2007 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-17642226

RESUMO

We report a case of hemothorax in a patient with von Recklinghausen's disease. A 40-year-old male was transfered to our hospital because of sudden severe right back pain. Chest computed tomography (CT) scan showed right hemothorax that ruptured intercostal artery. He underwent selective angiography that demonstrated a pseud aneurhysm in the 10th intercostals artery and treated with endovascular coil embolization. We conducted surgical right thoracic drainage on post embolization day 7. In the 2 year since his embolization and operation, there has been no recurrence of hemothorax.


Assuntos
Hemotórax/etiologia , Neurofibromatose 1/complicações , Neurofibromatose 1/diagnóstico , Adulto , Angiografia , Drenagem , Embolização Terapêutica , Hemotórax/diagnóstico , Humanos , Masculino , Neurofibromatose 1/terapia , Tomografia Computadorizada por Raios X , Resultado do Tratamento
4.
Insect Biochem Mol Biol ; 36(12): 911-20, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17098166

RESUMO

In order to understand the molecular mechanism of development during early embryogenesis in diapause and non-diapause of the silkworm, mRNA from diapause and non-diapause eggs was compared using the differential display technique. We cloned the full length of a cDNA encoding a novel RNA helicase-like (RHL) protein by the RACE method using a cDNA fragment which was one of the specific cDNAs in the non-diapause eggs. A BLAST search using the predicted amino acid sequence of RHL revealed a low homology (21-25% identity of its partial length) with that of the DEAD-box RNA helicase. Gene expression of the RHL gene of the diapause and non-diapause eggs was investigated by RT-PCR until 60h after oviposition. Amplified RHL cDNA was observed through all the stages in the non-diapause eggs, while in the diapause eggs, cDNA was found in eggs 0-12h after oviposition but disappeared 24-60h after oviposition. When the diapause eggs were activated by HCl treatment after chilling at 4 degrees C for 6 days from 48h after oviposition (artificial diapause termination), cDNA was observed from 12h after HCl treatment. We also investigated the immunohistochemical distribution and localization of RHL in non-diapause eggs using anti-recombinant His-tag RHL antiserum. RHL was distributed in blastoderm cells and yolk cells and was localized in the nucleus and the cytosol of yolk cells. These data suggest that RHL has an important role in the early embryo of the silkworm.


Assuntos
Bombyx/embriologia , Bombyx/enzimologia , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Insetos/metabolismo , RNA Helicases/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Bombyx/citologia , DNA Complementar/genética , Proteínas de Insetos/química , Dados de Sequência Molecular , Óvulo/citologia , Óvulo/metabolismo , Transporte Proteico , RNA Helicases/química , RNA Mensageiro/metabolismo
5.
J Nephrol ; 18(4): 436-41, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16245250

RESUMO

A 59 year-old woman showed rapidly progressive glomerulonephritis during immunotherapy for metastatic renal cell carcinoma. She received unilateral nephrectomy and cytotoxic T lymphocyte (CTL) therapy for the treatment of retroperitoneal lymph node metastasis of renal cell carcinoma. With CTL therapy, her retroperitoneal lymph node mass decreased in size. One year after the third round of CTL therapy, her serum creatinine was increased and massive proteinuria occurred. Her renal biopsy specimen revealed necrotizing and crescentic glomerulonephritis with immune complex deposition. Her retroperitoneal lymph node mass continued to decrease in size. Consequently, for the purpose of avoiding interfering with the CTL therapy, we performed double filtration plasmapheresis (DFPP) monotherapy for removal of immune complexes without using immunosuppressive drugs or prednisolone. After 24 sessions of DFPP, her serum IgG was reduced from 3,942 mg/dL to 2,400 mg/dL, and proteinuria (from 9.0 g/day to 0.9 g/day) and renal function (serum creatinine; from 5.6 mg/dL to 2.2 mg/dL) also improved. However, 3 months after the final DFPP, she expired due to perforation of the colon. The autopsy sample of the kidney showed that most of the glomeruli were obsolescent, but immunoglobulin depositions were reduced and necrotizing lesions were diminished. In the patients with RPGN associated with renal cell carcinoma, renal functional recovery has not been observed upon immunosuppressive treatment. Consequently, plasmapheresis is considered to be one of the effective and safe methods for patients with this association. We also discuss previous reports of RPGN associated with renal cell carcinoma, or RPGN after cancer immunotherapy.


Assuntos
Carcinoma de Células Renais/tratamento farmacológico , Glomerulonefrite/induzido quimicamente , Fatores Imunológicos/efeitos adversos , Interferon-alfa/efeitos adversos , Neoplasias Renais/tratamento farmacológico , Biópsia , Carcinoma de Células Renais/patologia , Progressão da Doença , Evolução Fatal , Feminino , Glomerulonefrite/patologia , Humanos , Fatores Imunológicos/uso terapêutico , Interferon-alfa/uso terapêutico , Neoplasias Renais/patologia , Pessoa de Meia-Idade
6.
Histopathology ; 43(2): 173-9, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12877733

RESUMO

AIMS: To investigate the expression of the cadherin complex in human crescentic glomerulonephritis to elucidate the role of intercellular adherens junction molecules in crescent formation. METHODS AND RESULTS: Immunostaining revealed cadherin complexes localized in Bowman's epithelial cells, but not in podocytes, of normal human glomeruli. Eight adult cases with myeloperoxidase anti-neutrophil cytoplasmic autoantibodies (MPO-ANCA)-related (pauci-immune type) crescentic glomerulonephritis were examined on immunofluorescence microscopy with anti-pan cadherin, p120 catenin, and beta-catenin antibodies. The specimens provided six cellular crescents, 12 fibrocellular crescents, and four fibrotic crescents. Immunofluorescence was semiquantitatively estimated by the rate of the field of localization within the whole area of the crescent, according to the four-grade system [(-) - (++)]. All the tested molecules consisting of the cadherin complex were abundantly observed in cytokeratin-positive epithelial components in crescents, each with an equivalent area of localization. The expression of the cadherin complex was closely associated with that of cytokeratin and both diminished as the crescents developed from cellular to fibrotic. CONCLUSIONS: The cadherin-catenin complex is a specific marker of Bowman's epithelial cells in human glomeruli. The cellular crescents in pauci-immune-type crescentic glomerulonephritis possess adherens junction molecules, indicating a principle parietal epithelial cell phenotype.


Assuntos
Moléculas de Adesão Celular/metabolismo , Glomerulonefrite por IGA/metabolismo , Glomérulos Renais/metabolismo , Fosfoproteínas/metabolismo , Junções Aderentes/metabolismo , Adulto , Idoso , Anticorpos Anticitoplasma de Neutrófilos/sangue , Biomarcadores/análise , Cateninas , Moléculas de Adesão Celular/análise , Feminino , Glomerulonefrite por IGA/patologia , Humanos , Glomérulos Renais/patologia , Masculino , Microscopia de Fluorescência , Pessoa de Meia-Idade , Peroxidase/sangue , Fosfoproteínas/análise , delta Catenina
7.
Insect Mol Biol ; 11(5): 443-51, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12230543

RESUMO

A cDNA library of maternal messages was constructed from non-fertilized Bombyx mori eggs collected just after oviposition without mating. cDNA clones were identified by their nucleotide sequences and evaluated as probes for RFLP linkage analysis. Back crossed F1 segregants - by crossing an F1 female (RF02 x RF50) and a male (RF02) - were used, which takes advantage of the phenomenon that no crossing over occurs in Bombyx females. Fifteen ordered BF1 segregants gave either homozygous (homo) or heterozygous (hetero) RFLP patterns with each cDNA probe. cDNA probes on the same linkage group gave the same homo/hetero order. One hundred and fifty one out of 248 cDNA clones showed polymorphisms between RF02 and RF50, and were therefore suitable as probes for RFLP linkage analysis in the present BF1 cross. They were sorted into twenty-seven linkage groups and one independent group, by the homo/hetero pattern matrix, covering all twenty-eight chromosomes in B. mori.


Assuntos
Bombyx/genética , Ligação Genética , Animais , Sequência de Bases , Cromossomos , Clonagem Molecular , DNA Complementar , Etiquetas de Sequências Expressas , Feminino , Humanos , Masculino , Dados de Sequência Molecular , Polimorfismo de Fragmento de Restrição
8.
Microbiol Immunol ; 45(4): 285-90, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11386418

RESUMO

Extracellular proteases of Staphylococcus aureus are emerging as potential virulence factors that are relevant to the pathogenicity of staphylococcal infections. These proteases may also be involved in the proteolytic cleavage of other exoproteins released from this organism. To define the target exoproteins and their sites of cleavage by proteases, high-resolution two-dimensional polyacrylamide gel electrophoresis followed by N-terminal amino acid sequencing of exoprotein spots was performed. Two to three hundred exoprotein spots were detected at the early-stationary phase of cultures of S. aureus NCTC8325, and then at the late-stationary stage most of these high molecular protein spots became invisible due to further proteolytic degradation. As the result of N-terminal analysis, lipase, triacylglycerol lipase, orf619 protein and orf388 protein were detected as multiple spots at the early-stationary phase. We found that these exoproteins were cleaved at 3, 7, 4 and 4 different sites, respectively, by proteases. According to the M.W. and pI of each peptide spot obtained from the gel and their matches with calculated values in addition to their N-terminal sequences, we showed that the positions of putative peptides resulted from proteolytic cleavage of these proteins.


Assuntos
Proteínas de Bactérias/isolamento & purificação , Endopeptidases/isolamento & purificação , Staphylococcus aureus/enzimologia , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Sítios de Ligação , Eletroforese em Gel Bidimensional , Endopeptidases/genética , Humanos , Lipase/genética , Lipase/isolamento & purificação , Dados de Sequência Molecular , Staphylococcus aureus/genética , Staphylococcus aureus/patogenicidade , Virulência
9.
Microbiol Immunol ; 44(8): 653-6, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11021395

RESUMO

Staphylococcus aureus and S. epidermidis are common pathogens in hospitals, and care should be taken not to disseminate these organisms among patients. We have focused on human hair as a source of bacterial contamination. We treated hair with culture solutions of S. aureus and S. epidermidis, and then performed scanning electron microscopy. Bacteria were detected on the surface of the cuticles of the hair, and the attached bacteria were not completely removed even by repeated washing with detergents. These results suggested that hair could be a source of bacterial contamination and indicated the importance of decontamination of hair.


Assuntos
Aderência Bacteriana/efeitos dos fármacos , Cabelo/microbiologia , Staphylococcus aureus/isolamento & purificação , Staphylococcus epidermidis/isolamento & purificação , Detergentes/farmacologia , Humanos , Microscopia Eletrônica de Varredura , Staphylococcus aureus/ultraestrutura , Staphylococcus epidermidis/ultraestrutura
10.
Cancer ; 90(4): 258-63, 2000 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-10966568

RESUMO

BACKGROUND: Cytologic specimens are one of the most important materials for lung carcinoma diagnosis, because they can be used in mass screening for lung carcinoma and early detection of cancer recurrence by examination of sputum and pleural fluid. METHODS: To prove the potentiality of the cytologic specimens to be subjected to molecular detection of recurrent lung carcinomas, the authors enrolled 16 patients who had undergone surgical treatment for lung carcinoma with recurrence detected by malignant pleural fluid. First, they examined K-ras gene and p53 tumor suppressor gene abnormalities in resected tumors by polymerase chain reaction-based single-strand conformation polymorphism (PCR-SSCP) analysis. Next, using a microdissection method, they investigated the use of cytologic specimens such as pleural fluid for the detection of recurrence by finding the same mutations observed in the initially resected tumor. RESULTS: Seven abnormally shifted bands were detected among six patients by PCR-SSCP analysis of surgical materials. Five of 7 abnormally shifted bands (71.4%) also were detected from microdissected malignant cells in cytologic smears. In two cases, they detected mutations by using single malignant cells in pleural fluid. CONCLUSIONS: The authors successfully detected the same mutations in recurrent cytologic specimens as those in the initially resected tumors by PCR-SSCP analysis. These findings suggest that the p53 and K-ras gene mutation patterns are effective markers for the detection of recurrent lung carcinoma in cytologic specimens. Cancer (Cancer Cytopathol)


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Genes ras/genética , Neoplasias Pulmonares/genética , Mutação/genética , Recidiva Local de Neoplasia/genética , Idoso , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Citodiagnóstico/métodos , DNA de Neoplasias/genética , Dissecação/métodos , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico , Derrame Pleural Maligno/genética , Derrame Pleural Maligno/patologia , Reação em Cadeia da Polimerase/métodos , Polimorfismo Conformacional de Fita Simples
11.
Artigo em Inglês | MEDLINE | ID: mdl-10818276

RESUMO

Dark-red pigment granules were found in the brain and ganglion of the normal strain of the silkworm, Bombyx mori, by light microscopy. No other pigmentation was seen in the brain or ganglia. Electron microscopy showed that the granules were electron-dense. The granules were similar to the ommochrome-containing pigment granules that are present in the epidermal cells of the quail mutant, as previously reported. The pigment in the larval central nervous system (CNS) of the normal silkworm was identical to the ommin standard with respect to the absorption spectrum, the infrared spectrum, and the Rf value in thin-layer chromatography (TLC). After acid hydrolysis of the pigment, 3-hydroxykynurenine was detected by TLC. The pigment granules in the CNS contained mainly ommin. An ommochrome-binding protein was also detected in the CNS by in vitro binding studies and Western blotting. The ommochrome granules may have an important function in the CNS of the silkworm.


Assuntos
Bombyx/química , Grânulos Citoplasmáticos/química , Pigmentos Biológicos/análise , Animais , Western Blotting , Bombyx/anatomia & histologia , Bombyx/crescimento & desenvolvimento , Química Encefálica , Sistema Nervoso Central/citologia , Sistema Nervoso Central/ultraestrutura , Cromatografia em Camada Fina , Larva/anatomia & histologia , Larva/química , Pigmentos Biológicos/imunologia
12.
Int J Cancer ; 89(1): 19-25, 2000 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-10719726

RESUMO

The arbitrarily primed polymerase chain reaction (AP-PCR) was used to detect somatic genetic alterations in lung carcinomas. DNA fingerprints generated by a single arbitrary primer were compared between normal and tumor tissues of the same individuals. We adapted the technique to the use of tissue fixed with methanol, which allowed the analysis of small areas of tissue by microdissection. This improvement of the fingerprinting technique permitted the study of tumors at early stages of progression. Loss of sequences from chromosome 7 was detected in 41.7% of adenocarcinomas and from chromosome 22 in 84.6% of small-cell carcinomas. Gains of sequences from chromosomes 1, 8 and 13 were detected in more than 40% of adenocarcinomas and in chromosome 2 in 63.3% of squamous-cell carcinomas. Our results indicate that allelic imbalances at these chromosomal regions are common genetic abnormalities in lung carcinomas. Loss of sequences from chromosome 22q13.3, found in 11 of 13 small-cell carcinomas, were confirmed by microsatellite PCR analysis. We show that the use of our improved AP-PCR fingerprinting permits the detection of both losses and gains of novel chromosomal regions early during lung cancer development. Our results indicate that early-stage tumors tend to have more allelic imbalances than relatively advanced tumors, suggesting a high tumor genetic heterogeneity in the early stages of lung tumor progression.


Assuntos
Aberrações Cromossômicas , Impressões Digitais de DNA/métodos , Neoplasias Pulmonares/genética , Reação em Cadeia da Polimerase/métodos , Adenocarcinoma/genética , Adenocarcinoma/patologia , Carcinoma de Células Pequenas/genética , Carcinoma de Células Pequenas/patologia , DNA de Neoplasias/análise , Humanos , Neoplasias Pulmonares/patologia , Metanol , Fixação de Tecidos
13.
Int J Cancer ; 84(6): 609-13, 1999 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-10567907

RESUMO

The p16 (CDKN2/MTS-1/INK4A) tumor-suppressor gene is frequently inactivated by DNA methylation in lung carcinomas. To clarify whether background anthracosis may play a role in DNA methylation and inactivation of the p16 gene, we examined DNA methylation of the p16-promoter region by methylation-specific polymerase chain reaction, and p16 expression immunohistochemically, and compared the results with the level of background anthracosis which was measured by an original quantitative method. At autopsy, DNA methylation of the p16 gene was observed in 6/19 tumors (32%) from patients who had died of pulmonary adenocarcinoma. The degree of background anthracosis (the effect of extrinsic carcinogenic factors) (mean absorbance value, A = 0.715) of the cases with p16-gene methylation was significantly higher than that without methylation (mean A value = 0.298). p16 expression was inactivated in all tumors with p16-gene methylation. The mean A value of black dust matter deposition in cases with normal expression of p16 (A = 0.151) was significantly lower than cases with abnormal expression of p16 (A = 0.531). These results indicate that the level of background anthracosis is closely associated with inactivation of p16 expression and also DNA methylation of the p16-gene promoter region in pulmonary adenocarcinogenesis. Int. J. Cancer (Pred. Oncol.) 84:609-613, 1999.


Assuntos
Adenocarcinoma/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Metilação de DNA , Neoplasias Pulmonares/metabolismo , Pneumoconiose/metabolismo , Adenocarcinoma/diagnóstico , Poeira/efeitos adversos , Poeira/análise , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/diagnóstico , Pneumoconiose/etiologia , Reação em Cadeia da Polimerase
20.
J Synchrotron Radiat ; 5(Pt 6): 1363-8, 1998 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-16687849

RESUMO

An ultrahigh-vacuum reaction apparatus to study synchrotron-radiation-stimulated processes has been constructed and placed on beamline 4B of the synchrotron radiation storage ring (UVSOR) at the Institute for Molecular Science. The apparatus is designed so that multiple synchrotron radiation processes such as etching and chemical vapour deposition can be carried out successively without breaking the high vacuum. It is equipped with IR reflection absorption spectroscopy (IRRAS) apparatus and reflective high-energy electron diffraction (RHEED) apparatus for in situ observations. The basic parameters of the apparatus including etching and deposition rates have been measured. IRRAS using buried metal layer substrates has been confirmed to be a very useful method of analyzing the reaction mechanisms of the synchrotron-radiation-stimulated processes.

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