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1.
Helminthologia ; 56(3): 219-228, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31662694

RESUMO

We morphologically and molecularly characterized segmented filamentous bacteria (SFB) associated with Rhigonema sp. nematodes in millipede hindguts. Seventy-three Riukiaria sp. millipedes were collected from a broad-leaf forest in Japan, and nematodes were excised from the millipede's hindguts. The occurrence rate of SFB associated with nematodes was 24 % (10/41) for males, 47 % (14/30) for females, and 100 % (2/2) for juveniles. Genomic DNA was extracted from four SFB-rich nematode heads, and we obtained 40 bacterial clones via analysis of nearly full-length 16S rDNA gene sequences. At the phylum level, Firmicutes, Proteobacteria, and Verrucomicrobia accounted for 55 %, 40 %, and 5 % of SFB, respectively. In Firmicutes, Clostridiaceae (28 %) and Lachnospiraceae (15 %) were the dominant groups. Our sequences were divided into seven and three subclades between Firmicutes and Proteobacteria in the phylogenetic tree. In the Firmicutes clade, eight sequences were classified as Lachnospiraceae with a bootstrap value >83 %. A phylogenetic tree involving known uncultured Lachnospiraceae sequences characterized the phylogenetic position of SFB associated with nematodes. Our results suggest that the association of SFB with nematode bodies was probably incidental and that SFB are not always present in millipede hindguts. Our bacterial groups corresponded to those of arthropod hindgut, and SFB associated with nematodes were inferred to belong to Lachnospiraceae. Because the Lachnospiraceae sequences obtained in this study showed specific lineages that differed from all the known deposited sequence data, these groups may be unique to Riukiaria sp.

2.
Osteoarthritis Cartilage ; 20(12): 1603-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22954457

RESUMO

OBJECTIVE: The p53 tumor-suppressor protein p53R2 is activated in response to various stressors that act on cell signaling. When DNA is damaged, phosphorylation of p53 at its Ser 15 residue induces p53R2 production. The role of p53R2 in chondrocytes remains poorly understood. In this study, we evaluated in chondrocytes, p53R2 expression and its regulation in response to mechanical stress. Furthermore, we investigated the function of p53R2 in relation to mechanotransduction. METHODS: Osteoarthritis (OA) cartilage obtained from total knee replacements and normal cartilage obtained from femoral neck fractures was used to measure p53R2 expression by using immunohistochemistry, western blotting, and real-time polymerase chain reaction (PCR). The OA chondrocytes were subjected to a high magnitude of cyclical tensile strain by using an FX-2000 Flexercell system. Next, sulfated glycosaminoglycan (sGAG) production was quantified in these cells. Protein expression of p53R2, and phosphorylation of Akt, p38MAPK, ERK1/2, and JNK was also detected using western blotting. Moreover, Akt phosphorylation was detected after transfecting the cells with p53R2-specific small interfering RNA (siRNA). RESULTS: Expression of p53R2 was significantly increased in OA chondrocytes and in chondrocytes after applying 5% tensile strain to the cells. However, Akt phosphorylation was down-regulated in OA chondrocytes after the strain, and was up-regulated after transfection of p53R2. sGAG protein as well as collagen type II and aggrecan mRNA was increased following transfection of p53R2-specific siRNA after 5% tensile strain. CONCLUSIONS: p53R2 could regulate matrix synthesis via Akt phosphorylation during chondrocyte mechanotransduction. Down-regulation of p53R2 may be a new therapeutic approach in OA therapy.


Assuntos
Cartilagem Articular/metabolismo , Proteínas de Ciclo Celular/genética , Condrócitos/metabolismo , Regulação da Expressão Gênica , Osteoartrite do Joelho/genética , Proteínas Proto-Oncogênicas c-akt/genética , RNA Mensageiro/genética , Ribonucleotídeo Redutases/genética , Western Blotting , Cartilagem Articular/patologia , Proteínas de Ciclo Celular/biossíntese , Células Cultivadas , Condrócitos/patologia , Reparo do DNA , Humanos , Imuno-Histoquímica , Osteoartrite do Joelho/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Ribonucleotídeo Redutases/biossíntese , Transdução de Sinais , Estresse Mecânico
3.
Osteoarthritis Cartilage ; 19(7): 903-10, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21420502

RESUMO

INTRODUCTION: Decoy receptor 3 (DcR3), a soluble receptor belonging to the tumor necrosis factor (TNF) receptor superfamily, competitively binds and inhibits the TNF family including Fas-ligand (Fas-L), lymphotoxin-like inducible protein that competes with glycoprotein D for binding herpesvirus entry mediator on T-cells (LIGHT) and TNF-like ligand 1A (TL1A). In this study, we investigated the functions of DcR3 on osteoarthritis (OA) chondrocytes. METHODS: Expressions of DcR3 in chondrocytes were measured by realtime Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR). Expression of DcR3 in sera and joint fluids was measured by enzyme-linked immunosorbent assay (ELISA). Chondrocytes were incubated with DcR3-Fc chimera protein (DcR3-Fc) before induction of apoptosis by Fas-L and apoptosis was detected with terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labelling labeling (TUNEL) staining and Western blotting of caspase 8 and poly (ADP-ribose) polymerase (PARP). Chondrocytes were incubated with DcR3-Fc and the proliferation was analyzed by 4-[3-(4-iodophenyl)-2-(4-nitrophenyl)-2H-5-tetrazolio]-1,3-benzene disulfonate (WST) assay. Phosphorylation of Extracellular Signal-Regulated Kinase (ERK), P38 mitogen-activated protein kinase (MAPK) and Jun N-terminal Kinase (JNK) in chondrocytes was measured by Western blotting after incubation with DcR3-Fc, Mitogen-activated protein kinase kinase (MEK1/2) inhibitor, or P38 MAPK inhibitor. Chondrocytes were treated with DcR3-Fc after pre-incubation with blocking antibody of Fas-L, LIGHT and TL1A, and proliferation or phosphorylation of ERK was analyzed. RESULTS: DcR3 was expressed in OA and normal chondrocytes. DcR3-Fc protects chondrocytes from Fas-induced apoptosis. DcR3-Fc increased chondrocytes proliferation and induced the phosphorylation of ERK specifically. DcR3-induced chondrocytes proliferation was inhibited by pre-incubation of PD098059 or blocking Fas-L antibody. DcR3 increased chondrocytes proliferation in OA chondrocytes, but did not in normal. CONCLUSION: DcR3 regulates the proliferation of OA chondrocytes via ERK signaling and Fas-induced apoptosis.


Assuntos
Proliferação de Células/efeitos dos fármacos , Condrócitos/efeitos dos fármacos , Condrócitos/metabolismo , Osteoartrite do Quadril/metabolismo , Membro 6b de Receptores do Fator de Necrose Tumoral/metabolismo , Membro 6b de Receptores do Fator de Necrose Tumoral/farmacologia , Apoptose/fisiologia , Western Blotting , Cartilagem Articular/metabolismo , Células Cultivadas/metabolismo , Ensaio de Imunoadsorção Enzimática , Humanos , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
4.
Mol Ecol ; 18(5): 985-96, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19207247

RESUMO

Comparisons of nematode communities among ecosystems have indicated that, unlike many organisms, nematode communities have less diversity in the tropics than in temperate ecosystems. There are, however, few studies of tropical nematode diversity on which to base conclusions of global patterns of diversity. This study reports an attempt to estimate nematode diversity in the lowland tropical rainforest of La Selva Biological Research Station in Costa Rica. We suggest one reason that previous estimates of tropical nematode diversity were low is because habitats above the mineral soil are seldom sampled. As much as 62% of the overall genetic diversity, measured by an 18S ribosomal barcode, existed in litter and understorey habitats and not in soil. A maximum-likelihood tree of barcodes from 360 individual nematodes indicated most major terrestrial nematode lineages were represented in the samples. Estimated 'species' richness ranged from 464 to 502 within the four 40 x 40 m plots. Directed sampling of insects and their associated nematodes produced a second set of barcodes that were not recovered by habitat sampling, yet may constitute a major class of tropical nematode diversity. While the generation of novel nematode barcodes proved relatively easy, their identity remains obscure due to deficiencies in existing taxonomic databases. Specimens of Criconematina, a monophyletic group of soil-dwelling plant-parasitic nematodes were examined in detail to assess the steps necessary for associating barcodes with nominal species. Our results highlight the difficulties associated with studying poorly understood organisms in an understudied ecosystem using a destructive (i.e. barcode) sampling method.


Assuntos
Biodiversidade , Nematoides/classificação , Chuva , Árvores , Clima Tropical , Animais , Costa Rica , Isópteros/parasitologia , Funções Verossimilhança , Dados de Sequência Molecular , Parasitos/classificação , Plantas/parasitologia , Dinâmica Populacional , Solo/parasitologia
5.
Bone Joint Res ; 7(3): 252-262, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29922443

RESUMO

OBJECTIVES: This study aimed to examine the effects of SRT1720, a potent SIRT1 activator, on osteoarthritis (OA) progression using an experimental OA model. METHODS: Osteoarthritis was surgically induced by destabilization of the medial meniscus in eight-week-old C57BL/6 male mice. SRT1720 was administered intraperitoneally twice a week after surgery. Osteoarthritis progression was evaluated histologically using the Osteoarthritis Research Society International (OARSI) score at four, eight, 12 and 16 weeks. The expression of SIRT1, matrix metalloproteinase 13 (MMP-13), a disintegrin and metalloproteinase with thrombospondin motifs-5 (ADAMTS-5), cleaved caspase-3, PARP p85, and acetylated nuclear factor (NF)-κB p65 in cartilage was examined by immunohistochemistry. Synovitis was also evaluated histologically. Primary mouse epiphyseal chondrocytes were treated with SRT1720 in the presence or absence of interleukin 1 beta (IL-1ß), and gene expression changes were examined by real-time polymerase chain reaction (PCR). RESULTS: The OARSI score was significantly lower in mice treated with SRT1720 than in control mice at eight and 12 weeks associated with the decreased size of osteophytes at four and eight weeks. The delayed OA progression in the mice treated with SRT1720 was also associated with increased SIRT1-positive chondrocytes and decreased MMP-13-, ADAMTS-5-, cleaved caspase-3-, PARP p85-, and acetylated NF-κB p65-positive chondrocytes and decreased synovitis at four and eight weeks. SRT1720 treatment partially rescued the decreases in collagen type II alpha 1 (COL2A1) and aggrecan caused by IL-1ß, while also reducing the induction of MMP-13 by IL-1ß in vitro. CONCLUSION: The intraperitoneal injection of SRT1720 attenuated experimental OA progression in mice, indicating that SRT1720 could be a new therapeutic approach for OA.Cite this article: K. Nishida, T. Matsushita, K. Takayama, T. Tanaka, N. Miyaji, K. Ibaraki, D. Araki, N. Kanzaki, T. Matsumoto, R. Kuroda. Intraperitoneal injection of the SIRT1 activator SRT1720 attenuates the progression of experimental osteoarthritis in mice. Bone Joint Res 2018;7:252-262. DOI: 10.1302/2046-3758.73.BJR-2017-0227.R1.

6.
J Med Chem ; 43(10): 2049-63, 2000 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-10821717

RESUMO

The search for new small-molecule CCR5 antagonists by high-throughput screening (HTS) of the Takeda chemical library using [(125)I]RANTES and CHO/CCR5 cells led to the discovery of lead compounds (A, B) with a quaternary ammonium or phosphonium moiety, which were synthesized to investigate new MCP-1 receptor antagonists. A series of novel anilide derivatives 1 with a quaternary ammonium moiety were designed, synthesized, and tested for their CCR5 antagonistic activity. Through the optimization of lead compounds, we have found N,N-dimethyl-N-[4-[[[2-(4-methylphenyl)-6, 7-dihydro-5H-benzocyclohepten-8-yl]carbonyl]amino]benzyl]tetrahydr o-2 H-pyran-4-aminium chloride (1r, TAK-779) as a highly potent and selective nonpeptide CCR5 antagonist with a IC(50) value of 1.4 nM in the binding assay. Compound 1r also inhibited the replication of macrophage (M)-tropic HIV-1 (Ba-L strain) in both MAGI-CCR5 cells and PBMCs with EC(50) values of 1.2 and 3.7 nM, respectively. The synthesis and structure-activity relationships of 1r and its related compounds are detailed.


Assuntos
Amidas/síntese química , Fármacos Anti-HIV/síntese química , Antagonistas dos Receptores CCR5 , HIV-1/efeitos dos fármacos , Compostos de Amônio Quaternário/síntese química , Amidas/farmacologia , Animais , Fármacos Anti-HIV/farmacologia , Células CHO , Linhagem Celular , Quimiocina CCL11 , Quimiocina CCL2/metabolismo , Quimiocina CCL5/metabolismo , Quimiocinas CC/metabolismo , Cricetinae , Citocinas/metabolismo , Radioisótopos do Iodo , Macrófagos/virologia , Estrutura Molecular , Compostos de Amônio Quaternário/farmacologia , Receptores CCR5/metabolismo , Relação Estrutura-Atividade , Replicação Viral/efeitos dos fármacos
7.
Biomaterials ; 22(21): 2921-9, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11561898

RESUMO

The potential energy surfaces associated with [Ca3(PO4)2n clusters are analyzed in detail using ab initio calculations for n ranging from one to four. Considering separated clusters, energy criteria favor the so-called Posner's cluster Ca9(PO4)6, which is the core of the actual structural model of amorphous calcium phosphate. This is rationalized through the existence of a distinct CaO bonding pattern in this cluster. Considering aggregated clusters as a possible model for amorphous calcium phosphate, the aggregation of Ca3(PO4)2 clusters appears as an alternative to Posner's hypothesis.


Assuntos
Materiais Biocompatíveis/química , Fosfatos de Cálcio/química , Substâncias Macromoleculares , Teste de Materiais , Modelos Químicos , Propriedades de Superfície , Termodinâmica
8.
Biomaterials ; 24(4): 579-85, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12437952

RESUMO

The in vitro bioactivity of a composite composed by a biodegradable starch-based polymeric matrix and hydroxyapatite fillers was investigated, in situ, as a function of immersion time in a simulated body fluid (SBF) using atomic force microscopy (AFM). The surface roughness of the composite started to increase after the initial 8h because of both the degradation of the polymer matrix and the nucleation of calcium phosphate. After 24h of immersion the surface of the composite was fully covered with calcium phosphate nuclei with diameters around 126 nm. As the immersion time increased, the nuclei increased both in number and size, and coalesced leading to the formation of a dense and uniform calcium phosphate layer on the surface of the composite only after 126 h of SBF immersion. The results of in situ AFM observation agreed with those of standard in vitro bioactivity tests in combination with scanning electron microscopy observations. Thin-film X-ray diffraction demonstrated that the ratio of apatite to the polymer matrix was higher within the surface layer (40 microm deep from the surface) than that in the bulk after the immersion for 7 days. The water-uptake capability of the polymer contributes to the nucleation and growth of the calcium phosphate layer. These results suggest the great potential of the composite for a range of temporary applications in which bone-bonding ability is a desired property.


Assuntos
Hidroxiapatitas/química , Amido/química , Materiais Biocompatíveis/química , Líquidos Corporais/química , Fosfatos de Cálcio/química , Humanos , Técnicas In Vitro , Teste de Materiais , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Polímeros/química , Propriedades de Superfície , Difração de Raios X
9.
Ann Nucl Med ; 12(4): 225-9, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9795711

RESUMO

UNLABELLED: Iodine-123 MIBG is a biochemical marker that can be used to monitor pulmonary norepinephrine (NE) metabolism. The purpose of this study was to characterize pulmonary I-123 MIBG kinetics in relation to age and gender. MATERIALS AND METHODS: Seventeen healthy volunteers and 14 patients with no cardiac or pulmonary disorders were included in this study (age range: 24 to 88 years, mean age 50.2 +/- 17.6 years; 16 males, 15 females). Planar images were obtained 15 min (early) and 3 h (delayed) after injection of I-123 MIBG (111 MBq). Pulmonary uptake of I-123 MIBG was quantified based on the lung-to-mediastinum ratio (LMR) on early and delayed images. The lung clearance rate (LCR) was calculated form both the early and delayed images. RESULTS: Both early and delayed LMR values increased slightly, although they showed no significant correlations with age. There was a significant inverse correlation between LCR and age (r = -0.57, p < 0.001). Neither LCR nor LMR differed significantly between male and female patients, but the mean age of the men was lower than that of the women. CONCLUSIONS: Pulmonary I-123 MIBG kinetics may reflect age-dependent changes in NE metabolism. The effects of age should be taken into account when assessing pulmonary NE metabolism with I-123 MIBG.


Assuntos
3-Iodobenzilguanidina/farmacocinética , Pulmão/metabolismo , Compostos Radiofarmacêuticos/farmacocinética , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Radioisótopos do Iodo , Pulmão/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Cintilografia , Fatores Sexuais
10.
Clin Nucl Med ; 22(10): 697-9, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9343727

RESUMO

A 72-year-old woman with Parkinson's disease and autonomic dysfunction underwent I-123 MIBG cardiac imaging to study sympathetic neuronal integrity. This revealed a defect in the infero-posterior wall. Tc-99m sestamibi myocardial perfusion imaging revealed no abnormalities. On follow-up I-123 MIBG SPECT, the defect was less prominent and the parkinsonian symptoms were ameliorated by drug therapy. Cardiac I-123 MIBG imaging may be a promising new method for evaluating drug therapy in patients with Parkinson's disease.


Assuntos
3-Iodobenzilguanidina , Antiparkinsonianos/uso terapêutico , Coração/diagnóstico por imagem , Radioisótopos do Iodo , Doença de Parkinson/tratamento farmacológico , Compostos Radiofarmacêuticos , Tomografia Computadorizada de Emissão de Fóton Único , Idoso , Doenças do Sistema Nervoso Autônomo/diagnóstico por imagem , Circulação Coronária , Droxidopa/uso terapêutico , Feminino , Seguimentos , Imagem do Acúmulo Cardíaco de Comporta , Cardiopatias/diagnóstico por imagem , Humanos , Pergolida/uso terapêutico , Volume Sistólico , Sistema Nervoso Simpático/diagnóstico por imagem , Tecnécio Tc 99m Sestamibi , Tomografia Computadorizada de Emissão de Fóton Único/métodos
11.
Gan To Kagaku Ryoho ; 27(7): 1039-42, 2000 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-10925691

RESUMO

The patient was a 69-year-old woman who had been diagnosed with a bowel obstruction due to colonic cancer, with simultaneous multiple pulmonary metastases. The primary lesion was resected and 5'-DFUR was administered for 2 years at an out-patient clinic. During those 2 years, there was no change in CEA value and the pulmonary lesions were fading on the roentogenograms. It then became doubtful whether the pulmonary shadows were real metastases or not, and 5'-DFUR administration was discontinued. After stopping the medication, her CEA value rose and the tumor shadows increased in intensity. 5'-DFUR was therefore re-administrated and her CEA value declined. Afterwards, a re-elevation in CEA value was seen, and low-dose FP therapy was added on an out-patient basis. Anti-cancer chemotherapy of 5'-DFUR (oral) and low-dose FP (i.v.) was contributed to her 5-year survival.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Neoplasias do Colo/patologia , Floxuridina/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/secundário , Administração Oral , Idoso , Antígeno Carcinoembrionário/sangue , Neoplasias do Colo/cirurgia , Esquema de Medicação , Feminino , Humanos
12.
Gan To Kagaku Ryoho ; 26 Suppl 2: 321-5, 1999 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-10630241

RESUMO

Home anti-cancer chemotherapy was performed for patients with advanced cancer of the digestive plantable venous port placed beneath the skin via the subclavian vein. 128 patients under 75 years old (enrolled: 6 patients with esophageal, 65 with gastric, 44 with colorectal, 5 with cholangio, 5 with pancreatic, one with hepatic and one with ileal cancer) were treated. Continuous intravenous infusion of 5-FU (300-400 mg/body/day) combined with low-dose injection of cisplatin (5 mg/body/day) was continued for 10 days, and repeated 3 times for 6 weeks. The response rate was 23.6% in 72 patients with valuation of tumor mass. In 83 patients for whom a tumor marker evaluation was also performed, an effect was seen in 30.1%. No severe side effects such as renal dysfunction were observed, and no special infusions were needed. Therefore, a quality of life was maintained in which bathing was possible and patients were released from the hospital. Hyperalimentation through the venous port, and palliation during the terminal stage, is easily accomplished. It is useful method for surgery, chemotherapy and palliative therapy in the treatment of cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias do Sistema Digestório/tratamento farmacológico , Terapia por Infusões no Domicílio , Bombas de Infusão Implantáveis , Idoso , Cisplatino/administração & dosagem , Equipamentos Descartáveis , Esquema de Medicação , Feminino , Fluoruracila/administração & dosagem , Humanos , Bombas de Infusão Implantáveis/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Veia Subclávia
15.
Br J Cancer ; 92(6): 1130-6, 2005 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-15770218

RESUMO

To seek for a candidate gene that would regulate tumour progression and metastasis in gastric cancer, we investigated gene expression profiles by using DNA microarray. Tumour tissue and adjacent normal tissue were obtained from 21 patients with gastric cancer and then examined for their gene expression profiles by the Gene Chip Human U95Av2 array, which includes 12 000 human genes and EST sequences. A total of 25 genes were upregulated and two genes were downregulated by at least four-fold in the tumour tissue. In a further analysis according to lymph node metastasis, the expressed levels of maspin, as well as carcinoembryonic antigen and nonspecific crossreacting antigen were significantly higher in tumours with lymph node metastasis than in those without it. Maspin expression in 85 gastric cancer patients was further investigated by using immunohistochemistry. Maspin expression was not observed in normal gastric epithelia without intestinal metaplasia. In contrast, maspin was expressed in 74 of 85 tumour tissues. There was a significant correlation between the incidence of maspin-positive tumour staining and lymph node metastasis. These results suggest that maspin has a potential role for tumour metastasis in gastric cancer.


Assuntos
Perfilação da Expressão Gênica , Serpinas/genética , Neoplasias Gástricas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Metilação de DNA , Feminino , Genes Supressores de Tumor , Humanos , Imuno-Histoquímica , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Regiões Promotoras Genéticas , Serpinas/análise , Neoplasias Gástricas/patologia
16.
Appl Opt ; 17(16): 2556-61, 1978 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-20203821

RESUMO

Effects of ion etching on the optical properties and lattice disorder of GaAs were studied by means of photoluminescence, He backscattering, and enhanced chemical etching. The photoluminescence intensity excited by a He-Cd laser (3250 A), which penetrates a distance of approximately 150 A into GaAs, is decreased to less than 20% of the initial value after ion etching by 100-eV Ar and recovered almost completely by 450 degrees C annealing. Helium backscattering and electron diffraction pattern indicate the existence of an amorphous layer, the thickness of which is 20% larger than the value estimated by LSS theory. Photoluminescence measurement shows that beyond this amorphous region there are distributed a lot of nonradiative recombination centers as well as radiative recombination centers which diffuse into the bulk. The depth of this distribution is larger than that of the amorphous region by 1 order of magnitude.

17.
J Clin Gastroenterol ; 32(2): 172-5, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11205658

RESUMO

Ulcerative colitis (UC) is a chronic inflammatory disease of the colon of unknown etiology. There are varied manifestations in the natural course of UC. However, duodenum is not generally considered a target organ of UC. Here, we report two patients with steroid-responsive ulcerative duodenitis with colitis that was consistent with UC, but not with Crohn's disease. We also reviewed six cases of ulcerative duodenitis with UC. Duodenal lesion with UC may be a more common phenomenon, although infrequently clinically manifested under steroid therapy. Upper gastrointestinal tract inflammation in UC warrants further studies to ascertain whether the duodenum is a target organ in UC, especially in steroid-free conditions.


Assuntos
Colite Ulcerativa/diagnóstico , Úlcera Duodenal/diagnóstico , Duodenite/diagnóstico , Adulto , Biópsia , Colite Ulcerativa/patologia , Colite Ulcerativa/cirurgia , Colo/patologia , Terapia Combinada , Úlcera Duodenal/patologia , Úlcera Duodenal/cirurgia , Duodenite/patologia , Duodenite/cirurgia , Duodenoscopia , Duodeno/patologia , Feminino , Humanos , Mucosa Intestinal/patologia , Masculino , Prednisolona/administração & dosagem
18.
J Bacteriol ; 171(6): 3187-91, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2722746

RESUMO

The nucleotide sequences of the genes for 6-aminohexanoate-cyclic-dimer hydrolases of Flavobacterium sp. strain K172 (F-nylA) and Pseudomonas sp. NK87 (P-nylA), enzymes essential for the degradation of a by-product of the nylon-6 industry, were obtained by the dideoxynucleotide chain-termination method. A 1,479-base-pair open reading frame starting at a GTG and terminating at a TGA was found for the both of the genes. The P-nylA and F-nylA genes encoded polypeptides of 493 amino acids and had only 10 base substitutions in the coding region, which caused seven amino acid substitutions.


Assuntos
Amidoidrolases/genética , Flavobacterium/enzimologia , Pseudomonas/enzimologia , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , DNA Bacteriano/genética , Flavobacterium/genética , Genes Bacterianos , Dados de Sequência Molecular , Pseudomonas/genética
19.
Scand J Gastroenterol ; 35(12): 1330-4, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11199376

RESUMO

The characteristic features of surgically curable mucin-producing extrahepatic bile duct carcinoma (MPEBC) have not previously been elucidated. Three (6.5%) of 46 patients who underwent surgery in our department for bile duct carcinoma between 1986 and 1997 had MPEBC. Clinicopathological features, diagnostic procedures and operative methods for patients with MPEBC were investigated. Tumors in the bile duct were identified by cholangioscopy combined with cholangiography after removal of mucin balls. Tumors were located close to the hepatic confluence in these patients. Two patients underwent hepatic lobectomy together with caudate lobectomy while the other underwent resection of the hepatic confluence. Absence of residual tumors was confirmed histologically in these patients. All three patients remain alive without evidence of recurrence, 22-54 months after surgery. MPEBC is a curable disease. Accurate localization in the biliary tree is essential and can only be obtained after, i) removal of mucin balls, and ii) extensive diagnostic work-up including cholangiography, cholangioscopy and intraoperative pathological examination.


Assuntos
Neoplasias dos Ductos Biliares/metabolismo , Neoplasias dos Ductos Biliares/cirurgia , Ductos Biliares Extra-Hepáticos , Mucinas/metabolismo , Adenocarcinoma Mucinoso/diagnóstico , Adenocarcinoma Mucinoso/cirurgia , Idoso , Neoplasias dos Ductos Biliares/diagnóstico , Humanos , Pessoa de Meia-Idade
20.
J Biomed Mater Res ; 62(1): 82-8, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12124789

RESUMO

The present work investigates, in situ, the in vitro bioactivity of partially crystallized 45S5 Bioglass (BG) as a function of immersion time in a simulated body fluid (SBF) using atomic force microscopy (AFM). The results obtained for the crystallized BG were compared to those of hydroxyapatite c- and a-faces. The calcium phosphate layer grows on the crystallized 45S5 B by multiple two-dimensional nucleation and fusion of these two-dimensional islands, which is essentially the same mode as for the hydroxyapatite c-face. The surface of the crystallized 45S5 BG was almost fully covered with a dense and compact calcium phosphate layer after 24 h. The calcium phosphate formation on the crystallized BG arises from a low surface energy of the surface layer and/or an effect of the layer to lower the resistance when the growth units of calcium phosphate incorporate into the growing island. These results indicate that the crystallized 45S5 BG is suitable to be used as a filler for polymeric matrix bioactive composites, as it maintains a high bioactivity associated with a stiffer behavior (as compared to standard BG).


Assuntos
Cerâmica/farmacocinética , Durapatita/farmacocinética , Materiais Biocompatíveis/farmacocinética , Biotransformação , Líquidos Corporais/metabolismo , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacocinética , Cristalização , Vidro , Cinética , Microscopia de Força Atômica , Propriedades de Superfície
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