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2.
Int J Lab Hematol ; 36(5): 521-30, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24373185

RESUMO

INTRODUCTION: The number of infused CD34(+) cells is crucial to the success of peripheral blood stem cell transplantation (PBSCT). Here, we present, for the first time, a new method of enumerating hematopoietic progenitor cells (HPCs) for PBSCT. METHOD: This novel method is based on hemolysis and chemical staining, followed by flow cytometry-based optical detection, conducted using an automated hematology analyzer (XN series, Sysmex). CD34(+) cells and HPCs were compared in 76 granulocyte colony-stimulating factor (G-CSF)-mobilized blood or apheresis samples taken from healthy donors (n = 18) or patients undergoing autologous PBSCT (n = 6). RESULTS: There was a strong correlation between the numbers of HPCs and CD34(+) cells (R(2)  = 0.958). The expected total number of HPCs in the final products, which was estimated from HPCs in pre-apheresis PB or mid-apheresis products, also correlated well with the total number of CD34(+) cells in the final products. The change in HPCs in PB closely resembled that of CD34(+) cells during mobilization. Experiments using immunomagnetic beads suggested that the majority of CD34(+) cells existed in HPCs, and vice versa. CONCLUSION: Hematopoietic progenitor cells may serve as surrogates for CD34(+) cells in PBSCT. However, further investigations are required to verify this.


Assuntos
Contagem de Células Sanguíneas/métodos , Células Sanguíneas/citologia , Neoplasias Hematológicas/terapia , Células-Tronco Hematopoéticas/citologia , Transplante de Células-Tronco de Sangue Periférico , Antígenos CD34/sangue , Automação Laboratorial , Biomarcadores/sangue , Contagem de Células Sanguíneas/instrumentação , Estudos de Casos e Controles , Fator Estimulador de Colônias de Granulócitos/farmacologia , Neoplasias Hematológicas/patologia , Mobilização de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/efeitos dos fármacos , Hemólise , Humanos , Transplante Autólogo
3.
Clin Exp Immunol ; 170(1): 86-93, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22943204

RESUMO

We investigated the non-genomic effects of glucocorticoids (GCs) on inhibition of plasma membrane lipid raft formation in activated human basophils. Human basophils obtained from house dust mite (HDM)-sensitive volunteers were pretreated with hydrocortisone (CORT) or dexamethasone (Dex) for 30 min and then primed with phorbol 12-myristate 13-acetate (PMA, 10 ng/ml) or HDM (10 µg/ml). The expression of CD63, a basophil activation marker, was assessed by flow cytometry. Membrane-bound GC receptors (mGCRs) were analysed by flow cytometry and confocal laser microscopy. Lipid rafts were assessed using a GM1 ganglioside probe and visualization by confocal laser microscopy. Pretreatment of basophils with CORT (10(-4) M and 10(-5) M) and Dex (10(-7) M) significantly inhibited CD63 expression 20 min after addition of PMA or HDM. The inhibitory effects of GCs were not altered by the nuclear GC receptor (GCR) antagonist RU486 (10(-5) M) or the protein synthesis inhibitor cycloheximide (10(-4) M) (P < 0·05). CORT coupled to bovine serum albumin (BSA-CORT) mimicked the rapid inhibitory effects of CORT, suggesting the involvement of mGCRs. mGCRs were detectable on the plasma membrane of resting basophils and formed nanoclusters following treatment with PMA or HDM. Pretreatment of cells with BSA-CORT inhibited the expression of mGCRs and nanoclustering of ganglioside GM1 in lipid rafts. The study provides evidence that non-genomic mechanisms are involved in the rapid inhibitory effect of GCs on the formation of lipid raft nanoclusters, through binding to mGCRs on the plasma membrane of activated basophils.


Assuntos
Basófilos/efeitos dos fármacos , Glucocorticoides/farmacologia , Microdomínios da Membrana/efeitos dos fármacos , Pyroglyphidae/metabolismo , Receptores de Glucocorticoides/metabolismo , Animais , Basófilos/imunologia , Basófilos/metabolismo , Bovinos , Membrana Celular/imunologia , Membrana Celular/metabolismo , Células Cultivadas , Cicloeximida/farmacologia , Dexametasona/imunologia , Dexametasona/farmacologia , Citometria de Fluxo , Gangliosídeo G(M1)/metabolismo , Regulação da Expressão Gênica , Glucocorticoides/imunologia , Humanos , Hidrocortisona/imunologia , Hidrocortisona/farmacologia , Leucócitos Mononucleares/citologia , Microdomínios da Membrana/imunologia , Microdomínios da Membrana/metabolismo , Microscopia Confocal , Mifepristona/farmacologia , Pyroglyphidae/imunologia , Receptores de Glucocorticoides/análise , Receptores de Glucocorticoides/antagonistas & inibidores , Soroalbumina Bovina/metabolismo , Acetato de Tetradecanoilforbol/imunologia , Acetato de Tetradecanoilforbol/farmacologia , Tetraspanina 30/análise , Tetraspanina 30/antagonistas & inibidores
4.
Acta Neurochir (Wien) ; 150(8): 749-56; discussion 756, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18633571

RESUMO

OBJECT: Although a pre-temporal approach (PA) can provide a wide space for preservation of thalamoperforating atrteries in direct surgery for basilar bifurcation aneurysms (BBAs), it cannot always secure adequate proximal control. The authors described the advantages of plical resection added to PA for BBAs. METHODS: Between October 1998 and April 2000, eight consecutive patients with BBAs were treated in the neurosurgical department of Kurashiki Central Hospital. Among them, five patients received direct clipping using this method. There were four females and one male, ages ranging from 61 to 77 (mean 70.8 years). Mean aneurysmal size and distance between the in"terclinoidal line and the aneurysmal neck was 4.5 and 9.5 mm, respectively. The operative procedures consisted of the following components; 1) fronto-temporal craniotomy with translocation of orbito-zygomatico-malar bone for PA, 2) preservation of lateral branches of the superficial sylvian veins, 3) resection of plica dural folds to increase the operative field up to the oculomotor nerve (OMN). RESULTS: Complete clipping was achieved without thalamic infarction or temporal contusion in all patients. Three of the five patients suffered from transient right OMN palsy which recovered within two months after surgery. CONCLUSION: Plical resection in the pre-temporal approach might be beneficial in the surgical treatment of BBAs when proximal control seems difficult.


Assuntos
Artéria Basilar/cirurgia , Craniotomia/métodos , Aneurisma Intracraniano/cirurgia , Procedimentos Neurocirúrgicos/métodos , Idoso , Dura-Máter/cirurgia , Feminino , Osso Frontal/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Oftalmoplegia/etiologia , Complicações Pós-Operatórias/etiologia , Base do Crânio/cirurgia , Osso Temporal/cirurgia
5.
AJNR Am J Neuroradiol ; 29(5): 868-74, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18296548

RESUMO

BACKGROUND AND PURPOSE: In the treatment of carotid atherosclerosis, the rate of stenosis and characteristics of plaque should be assessed to diagnose vulnerable plaques that increase the risk for cerebral infarction. We performed carotid black-blood (BB) MR imaging to diagnose plaque components and assess plaque hardness based on MR signals. MATERIALS AND METHODS: Three images of BB-MR imaging per plaque were obtained from 70 consecutive patients who underwent carotid endarterectomy (CEA) to generate T1- and T2-weighted images. To evaluate the relative signal intensity (rSI) of plaque components and the relationship between histologic findings and symptoms, we prepared sections at 2-mm intervals from 34 intact plaques. We then calculated the relative overall signal intensity (roSI) of 70 plaques to assess the relationship between MR signal intensity and plaque hardness and symptoms. RESULTS: The characteristics of rSI values on T1- and T2-weighted images of fibrous cap (FC), fibrosis, calcification, myxomatous tissue, lipid core (LC) with intraplaque hemorrhage (IPH), and LC without IPH differed. Symptomatic plaques were associated with FC disruption (P < .001) and LC with IPH (P < .05). The roSI on T1-weighted images was significantly higher for soft than nonsoft plaques. When the roSI cutoff value was set at 1.25 (mean of the roSI), soft plaques were diagnosed with 79.4% sensitivity and 84.4% specificity. The roSI was also significantly higher for symptomatic than for asymptomatic plaques. Soft and nonsoft plaques as well as symptomatic and asymptomatic plaques did not significantly differ on T2-weighted images. CONCLUSION: BB-MR imaging can diagnose plaque components and predict plaque hardness. This procedure provides useful information for planning therapeutic strategies of carotid atherosclerosis.


Assuntos
Células Sanguíneas/patologia , Estenose das Carótidas/patologia , Interpretação de Imagem Assistida por Computador/métodos , Armazenamento e Recuperação da Informação/métodos , Imageamento por Ressonância Magnética/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
J Exp Clin Cancer Res ; 25(2): 195-200, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16918130

RESUMO

Transplatin (TDDP), a trans-isomer of cisplatin (CDDP), is well known to have faint cytotoxicity because its geometric structure allows less adduct formation with DNA than does CDDP. However, TDDP might have the potential to enhance the anticancer effect of 5-fluorouracil (5-FU) as well as CDDP. In this study, five gastric cancer cell lines were used. Cells were treated with 5-FU, TDDP, TDDP+5-FU, CDDP, and CDDP+5-FU, for 72 hrs. Synergistic effects between TDDP and 5-FU were observed in OCUM-2MD3, OCUM-2M, and OCUM-11, though they were not observed in MKN-45 or MKN-28. The cell lines in which synergistic effects were observed between TDDP and 5-FU were the same ones in which synergistic effects are shown between CDDP and 5-FU. The cell lines without synergism between 5-FU +TDDP/CDDP had lower thymidylate synthase (TS) activities than those with synergism, suggesting TS might be attributable to the synergistic mechanism. TDDP alone, compared to CDDP alone, gave rather low cytotoxicity for these cell lines. In conclusion, TDDP might be a clinically useful modulator of 5-FU.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Cisplatino/farmacologia , Fluoruracila/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Sinergismo Farmacológico , Humanos , Estereoisomerismo , Células Tumorais Cultivadas/efeitos dos fármacos
7.
Br J Neurosurg ; 19(1): 55-6, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16147585

RESUMO

An Onodi cell is defined as the most posterior ethmoid cell, which pneumatizes laterally and superiorly to the sphenoid sinus. A rare case of an isolated mucocele in an Onodi cell with unilateral acute visual disturbance is presented. MRI was imperative for the early and accurate diagnosis, and prompt surgical drainage resulted in dramatic visual recovery.


Assuntos
Mucocele/complicações , Doenças do Nervo Óptico/etiologia , Doenças dos Seios Paranasais/complicações , Seio Esfenoidal/diagnóstico por imagem , Doença Aguda , Feminino , Humanos , Pessoa de Meia-Idade , Mucocele/diagnóstico por imagem , Doenças do Nervo Óptico/diagnóstico por imagem , Doenças dos Seios Paranasais/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Transtornos da Visão/etiologia
8.
Gene Ther ; 12(1): 95-100, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15385954

RESUMO

Increase of Skp-2, which is involved in the degradation of cell cycle regulators including p27Kip1, p21 and c-myc, is one of the important mechanisms for dysregulation of cell cycles in various cancers. We applied RNA interference (RNAi) for Skp-2 by using HIV-lentiviral or adenoviral vectors for a human small-cell lung carcinoma cell line with increased Skp-2 to evaluate RNAi strategy for cancer gene therapy. HIV-lentivirus-mediated RNAi for Skp-2 resulted in efficient inhibition of the in vitro cell growth of cancer cells with increased Skp-2 through the increase of p27Kip1 and p21, but no significant effect on the growth of cells without high Skp-2 expression. Furthermore, intratumoral administration of adenovirus siRNA vector for Skp-2 efficiently inhibited growth of established subcutaneous tumor on NOD/SCID mice. These results indicate that the Skp-2 RNAi may be a useful strategy for gene therapy of cancers with high Skp-2 expression.


Assuntos
Carcinoma de Células Pequenas/terapia , Terapia Genética/métodos , Neoplasias Pulmonares/terapia , Interferência de RNA , Proteínas Quinases Associadas a Fase S/genética , Adenoviridae/genética , Animais , Linhagem Celular Tumoral , Engenharia Genética , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , HIV/genética , Masculino , Camundongos , Camundongos SCID
9.
Kyobu Geka ; 57(12): 1113-6, 2004 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-15553027

RESUMO

We report use of a new bronchial blocker through a single-lumen endotracheal tube to achieve one-lung ventilation to perform thoracoscopic operation in patients in whom placement of the double-lumen tube failed and difficult intubation is predicted. The bronchial blocker tube was placed into the aimed bronchus under the bronchoscopic vision and the cuff of the blocker was inflated to achieve one-lung ventilation. In all of the 4 patients, the bronchial blocker could be inserted and placed safely, quickly, and exactly under the fiberoptic flexible bronchoscopic vision to perform thoracoscopic operation without any complications. The new bronchial blocker tube through the indwelling endotracheal tube may have advantages in situations where placement of double-lumen endotracheal tubes is technically impossible or inappropriate. The use of the new bronchial blocker tube will, however, require careful evaluation in larger series.


Assuntos
Brônquios , Intubação Intratraqueal/instrumentação , Toracoscopia/métodos , Idoso , Idoso de 80 Anos ou mais , Anestesia Geral , Biópsia , Desenho de Equipamento , Segurança de Equipamentos , Feminino , Tecnologia de Fibra Óptica , Humanos , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Pneumonectomia , Respiração Artificial/métodos
10.
Kyobu Geka ; 57(6): 450-4, 2004 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-15202263

RESUMO

We have performed 5 thoracoscopic pericardial resections for malignant pericardial effusions. An initial trocar was placed in the seventh or eighth intercostal space posterior to the midaxillary line. Two additional trocars were placed, usually in the sixth intercostals spaces in the anterior axillary and posterior axillary lines. Using an endoscopic grasping instrument and scissors through the working ports, a pericardial resection was performed. All patients were successfully managed by thoracoscopic pericardial resections. Two of the 5 patients had associated malignant pleural effusions that were able to be managed at the same time by thoracoscopy. The average chest tube duration was 1.8 days. There has been no reaccumulation of pericardial effusions in all patients at an average follow-up of 5 months. The thoracoscopic approach could be minimally invasive and the procedure of choice in performing pericardial resections in selected patients with malignant pericardial effusions who are expected to have a reasonable life expectancy.


Assuntos
Adenocarcinoma/complicações , Neoplasias Pulmonares/complicações , Derrame Pericárdico/cirurgia , Pericardiectomia/métodos , Pericardite/cirurgia , Toracoscopia , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Derrame Pericárdico/etiologia , Pericardite/etiologia
11.
Kyobu Geka ; 56(11): 913-7, 2003 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-14579692

RESUMO

The injury of the lung occurred during thoracoscopic operation, especially, of the fragile, severely emphysematous lung is often difficult to treat. A fibrin glue spraying device in which an air compressor was connected to an intravenous catheter was constructed, and connected to a Dupuloject syringe. Fibrin glue was administered by spraying on the target lesion under a thoracoscopic vision. The procedure was done while the tip of the intravenous catheter was held and manipulated with forceps through a thoracoport. And then, the polyglycolic acid (PGA) mesh that had been cut into small pieces was put on the target lesion with forceps. Fibrin glue was sprayed on the lesion again in the above-mentioned manner. When necessary, the procedure was repeated. Our technique during thoracoscopic operation may be easy to manipulate and be able to apply the target lesion uniformly within a short time with a successful repair.


Assuntos
Adesivo Tecidual de Fibrina/uso terapêutico , Complicações Intraoperatórias , Lesão Pulmonar , Pneumonectomia/métodos , Ácido Poliglicólico , Telas Cirúrgicas , Toracoscopia/métodos , Idoso , Humanos , Masculino , Enfisema Pulmonar/cirurgia
12.
Eur Respir J ; 22(3): 457-61, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14516135

RESUMO

Reactive nitrogen species (RNS) have been reported to be involved in the inflammatory process in chronic obstructive pulmonary disease (COPD). However, there are no studies on the modulation of RNS in COPD. It was hypothesised that inhibition of xanthine oxidase (XO) might decrease RNS production in COPD airways through the suppression of superoxide anion production. Ten COPD and six healthy subjects participated in the study. The XO inhibitor allopurinol (300 mg x day(-1) p.o. for 4 weeks) was administered to COPD patients. RNS production in the airway was assessed by 3-nitrotyrosine immunoreactivity and enzymic activity of XO in induced sputum as well as by exhaled nitric oxide (eNO) concentration. XO activity in the airway was significantly elevated in COPD compared with healthy subjects. Allopurinol administration to COPD subjects significantly decreased XO activity and nitrotyrosine formation. In contrast, eNO concentration was significantly increased by allopurinol administration. These results suggest that oral administration of the xanthine oxidase inhibitor allopurinol reduces airway reactive nitrogen species production in chronic obstructive pulmonary disease subjects. This intervention may be useful in the future management of chronic obstructive pulmonary disease.


Assuntos
Alopurinol/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Espécies Reativas de Nitrogênio/biossíntese , Tirosina/análogos & derivados , Tirosina/biossíntese , Xantina Oxidase/antagonistas & inibidores , Idoso , Testes Respiratórios , Feminino , Humanos , Pulmão/metabolismo , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/análise , Doença Pulmonar Obstrutiva Crônica/metabolismo , Escarro/citologia
13.
Kyobu Geka ; 56(1): 23-7, 2003 Jan.
Artigo em Japonês | MEDLINE | ID: mdl-12607249

RESUMO

When a metastatic lung tumor is found to be deep to the visceral surface of the pleura, or when it is found to be a small lesion, it may important to help identify the lesion by preoperative methods in order to localize it at the time of thoracoscopic operation. We performed computed tomography-guided localization of metastatic lung tumors with use of a needle with a suture in 11 cases prior to thoracoscopic resection. Placement of the needle, immediately before moving to the operation room were successfully performed in all patients. It took from 16 to 25 minutes (20.3 minutes on average). Complications included minimal pneumothorax in 8 patients, mild airway bleeding in 2, and penetration through the middle lobe to the lower lobe of the right lung in 1. However, treatment was not necessary in any of the patients. Thoracoscopic resections were successfully achieved in all patients. Our technique may be a simpler technique and advantageous for identification of small lesions and lesions deep to the visceral surface of the pleura during the thoracoscopic operation for metastatic lung tumors.


Assuntos
Neoplasias Pulmonares/secundário , Neoplasias Pulmonares/cirurgia , Pneumonectomia/métodos , Cirurgia Torácica Vídeoassistida/métodos , Tomografia Computadorizada por Raios X , Idoso , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Masculino , Agulhas , Suturas , Resultado do Tratamento
14.
Int J Cancer ; 94(3): 328-34, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11745410

RESUMO

We previously reported that ganglioside GD1a, which is highly expressed in poorly metastatic FBJ-S1 cells, inhibits the serum-induced motility of FBJ-LL cells and that the metastatic potential of FBJ-LL cells is completely suppressed by enforced GD1a expression (Hyuga et al., Int J Cancer 1999;83:685-91). We recently discovered that hepatocyte growth factor (HGF) induces FBJ-LL cell motility. In the present study, the HGF-induced motility of FBJ-S1 cells was found to be one-thirtieth that of FBJ-LL cells. This motility of GD1a-expressing transfectants, which were produced by transfection of FBJ-LL cells with GM2/GD2 synthase cDNA, decreased with increases in their GD1a expression and HGF induced almost no motility in GD1a-pretreated FBJ-LL cells, indicating that GD1a inhibits the HGF-induced motility of FBJ-LL cells. The expression of the HGF receptor c-Met on FBJ-S1 cells, FBJ-LL cells, transfectants and a mock-transfectant was almost the same. The level of tyrosine phosphorylation of c-Met after HGF stimulation in FBJ-S1 cells, GD1a-pretreated FBJ-LL cells and a GD1a-expressing transfectant was significantly lower than in FBJ-LL cells and a mock-transfectant. These findings suggested that GD1a inhibits the HGF-induced motility of FBJ-LL cells through suppression of tyrosine phosphorylation of c-Met. HepG2 cells, a human hepatoma cell line, were used to investigate whether GD1a interferes with other cancer cells expressing c-Met. HepG2 cells did not express GD1a. HGF induced cell scattering of HepG2 cells and the scattering was inhibited by pretreating the cells with GD1a. The c-Met in the cells was autophosphorylated by stimulation with HGF, but after treating the cells with GD1a, the HGF-induced autophosphorylation of c-Met was suppressed. These results suggest that GD1a acts as a negative regulator of c-Met in cancer cells.


Assuntos
Gangliosídeo G(M1)/análogos & derivados , Gangliosídeo G(M1)/farmacologia , Fator de Crescimento de Hepatócito/metabolismo , Neoplasias/metabolismo , Actinas/metabolismo , Animais , Western Blotting , Movimento Celular , DNA Complementar/metabolismo , Citometria de Fluxo , Gangliosídeos/metabolismo , Camundongos , Fosforilação , Testes de Precipitina , Proteínas Proto-Oncogênicas c-met/imunologia , Transdução de Sinais , Fibras de Estresse/metabolismo , Fatores de Tempo , Transfecção , Células Tumorais Cultivadas , Tirosina/metabolismo
15.
Biochim Biophys Acta ; 1549(1): 61-72, 2001 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-11566369

RESUMO

The oah1 gene of an extremely thermophilic bacterium, Thermus thermophilus HB8, was cloned, sequenced, and overexpressed in Escherichia coli cells. The gene product having a high O-acetyl-L-homoserine sulfhydrylase (EC 4.2.99.10) activity was purified to homogeneity, with a recovery of approximately 40% and a purification ratio of 81-fold, both calculated from the cell-homogenate. The protein showed molecular masses of approximately 163000 (for the native form) and 47000 (for the subunit). The isoelectric point was pH 6.0. The optimum temperature and pH for the activity were approximately 70 degrees C and pH 7.8, respectively. The enzyme was also shown to be very stable at high temperature (90% activity remaining at 90 degrees C for 60 min at pH 7.8) and in a wide range of pH (pH 4-12 at room temperature). The absorption spectrum showed a peak at 425 nm, and hydroxylamine hydrochloride (0.1 mM) inhibited approximately 90% of the activity, suggesting formation of a Schiff base with pyridoxal 5'-phosphate. The enzyme showed an apparent K(m) value of 6.8 mM for O-acetyl-L-homoserine, a V(max) value of 165 micromol/min per mg of protein at a fixed sulfide concentration of 5 mM, and also an apparent K(m) value of approximately 1.3 mM for sulfide (with 25 mM acetylhomoserine). L-Methionine (1 mM) inhibited the enzyme activity by 67%. Based on these findings, it was discussed that this enzyme might be inactive under ordinary conditions but might become active as an alternative homocysteine synthase in T. thermophilus HB8, only under such conditions as deficiency in transsulfuration, bringing about a sufficient amount of sulfide available in the cell.


Assuntos
Carbono-Oxigênio Liases/genética , Genes Bacterianos , Complexos Multienzimáticos , Proteínas de Saccharomyces cerevisiae , Thermus thermophilus/genética , Carbono-Oxigênio Liases/biossíntese , Carbono-Oxigênio Liases/química , Catálise , Clonagem Molecular , Cisteína Sintase , Inibidores Enzimáticos/química , Estabilidade Enzimática , Escherichia coli/genética , Escherichia coli/metabolismo , Concentração de Íons de Hidrogênio , Focalização Isoelétrica , Dados de Sequência Molecular , Espectrofotometria Ultravioleta , Temperatura , Thermus thermophilus/enzimologia
16.
J Bacteriol ; 183(6): 2086-92, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11222609

RESUMO

A cell extract of an extremely thermophilic bacterium, Thermus thermophilus HB8, cultured in a synthetic medium catalyzed cystathionine gamma-synthesis with O-acetyl-L-homoserine and L-cysteine as substrates but not beta-synthesis with DL-homocysteine and L-serine (or O-acetyl-L-serine). The amounts of synthesized enzymes metabolizing sulfur-containing amino acids were estimated by determining their catalytic activities in cell extracts. The syntheses of cystathionine beta-lyase (EC 4.4.1.8) and O-acetyl-L-serine sulfhydrylase (EC 4.2.99.8) were markedly repressed by L-methionine supplemented to the medium. L-Cysteine and glutathione, both at 0.5 mM, added to the medium as the sole sulfur source repressed the synthesis of O-acetylserine sulfhydrylase by 55 and 73%, respectively, confirming that this enzyme functions as a cysteine synthase. Methionine employed at 1 to 5 mM in the same way derepressed the synthesis of O-acetylserine sulfhydrylase 2.1- to 2.5-fold. A method for assaying a low concentration of sulfide (0.01 to 0.05 mM) liberated from homocysteine by determining cysteine synthesized with it in the presence of excess amounts of O-acetylserine and a purified preparation of the sulfhydrylase was established. The extract of cells catalyzed the homocysteine gamma-lyase reaction, with a specific activity of 5 to 7 nmol/min/mg of protein, but not the methionine gamma-lyase reaction. These results suggested that cysteine was also synthesized under the conditions employed by the catalysis of O-acetylserine sulfhydrylase using sulfur of homocysteine derived from methionine. Methionine inhibited O-acetylserine sulfhydrylase markedly. The effects of sulfur sources added to the medium on the synthesis of O-acetylhomoserine sulfhydrylase and the inhibition of the enzyme activity by methionine were mostly understood by assuming that the organism has two proteins having O-acetylhomoserine sulfhydrylase activity, one of which is cystathionine gamma-synthase. Although it has been reported that homocysteine is directly synthesized in T. thermophilus HB27 by the catalysis of O-acetylhomoserine sulfhydrylase on the basis of genetic studies (T. Kosuge, D. Gao, and T. Hoshino, J. Biosci. Bioeng. 90:271-279, 2000), the results obtained in this study for the behaviors of related enzymes indicate that sulfur is first incorporated into cysteine and then transferred to homocysteine via cystathionine in T. thermophilus HB8.


Assuntos
Homocisteína/biossíntese , Enxofre/metabolismo , Thermus thermophilus/metabolismo , Meios de Cultura , Cistationina/biossíntese , Cistationina/metabolismo , Cistationina gama-Liase/metabolismo , Cisteína/biossíntese , Cisteína/metabolismo , Cisteína Sintase/biossíntese , Cisteína Sintase/metabolismo , Regulação Bacteriana da Expressão Gênica , Liases/biossíntese , Liases/metabolismo , Metionina/metabolismo , S-Adenosilmetionina/metabolismo , Temperatura , Thermus thermophilus/genética , Thermus thermophilus/crescimento & desenvolvimento
17.
Carbohydr Res ; 329(4): 755-63, 2000 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11125817

RESUMO

A lactoside primer, 12-azidododecyl beta-lactoside, was synthesized via the Koenigs-Knorr method by glycosylation of 1,12-dodecyldiol with perbenzoylated lactosyl bromide. The presence of the 2-O-acyl substituent in the donor gave the beta-lactoside, and an excess of acceptor ensured monoglycosylation of the diol. Mesylation of the omega-hydroxyl group in the aglycon, followed by displacement of the mesylate with azide and subsequent O-debenzoylation gave the desired omega-azidododecyl beta-lactoside. The azido glycoside primer was examined in mouse B16 melanoma cells for its feasibility as a building block for oligosaccharide biosynthesis. Uptake of the azido glycoside primer by B16 cells resulted in the sialylation of the galactose residue of the primer to give a glycosylated product having the same glycan as in ganglioside GM3. After 24 h incubation of B16 cells with the primers, the amount of sialylated omega-azidododecyl beta-lactoside primer was 75% of the amount of sialylated n-dodecyl beta-lactoside. However, after 48 h incubation, both primers gave equal amounts of the sialylated products. Interestingly, the remaining azido glycoside primer after 48 h incubation was 5.6-fold greater than that of the alkyl primer, indicating degradation of the alkyl primer to a larger extent than the omega-azido glycoside primer. The facile chemical synthesis and the efficient uptake in cells make the azido glycoside primer a versatile building block for the biocombinatorial synthesis of glycolipid oligosaccharides.


Assuntos
Azidas/química , Azidas/síntese química , Glicosídeos/síntese química , Glicosídeos/metabolismo , Glicoesfingolipídeos/biossíntese , Glicoesfingolipídeos/química , Lactose/química , Lactose/síntese química , Animais , Azidas/metabolismo , Azidas/farmacologia , Transporte Biológico , Divisão Celular/efeitos dos fármacos , Gangliosídeo G(M3)/análogos & derivados , Gangliosídeo G(M3)/química , Glicosídeos/química , Glicosídeos/farmacologia , Glicosilação , Humanos , Lactose/análogos & derivados , Lactose/metabolismo , Lactose/farmacologia , Melanoma Experimental , Camundongos , Estrutura Molecular , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Células Tumorais Cultivadas
18.
No Shinkei Geka ; 28(10): 885-9, 2000 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-11070909

RESUMO

A 61-year-old man was admitted to our hospital for mild left hemiparesis and speech disturbance. An initial angiogram revealed occlusion of the right internal carotid artery (ICA) but with sufficient collateral flow by compensated the contralateral carotid artery. Severe stenosis (70%) in the intracavernous (C4-5) portion was identified in the left ICA. Cerebral blood flow was remarkably decreased in both hemispheres. The patient's hemiparesis fluctuated according to the systemic blood pressure in such a manner that induced hypertension therapy was mandatory. On the 19th hospital day, we performed stenting of the left ICA stenosis using a coronary stent. A flexible coronary stent, NIR PRIMO stent 3.0 mm/16 mm (SCIMED, Boston Scientific) was deployed after the predilatation (2.5 mm/10 atm). The initial 70% stenosis was reduced to 6% after the postdilatation (3.75 mm/8 atm). The neurological status was stable after the procedure and we stopped the induced hypertension therapy the next day. We consider that intracranial artery stenting will be a common therapeutic modality in the near future.


Assuntos
Estenose das Carótidas/cirurgia , Vasos Coronários/cirurgia , Stents , Artéria Carótida Interna , Estenose das Carótidas/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada de Emissão de Fóton Único
19.
J Hepatobiliary Pancreat Surg ; 7(1): 63-71, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10982594

RESUMO

The early diagnosis of pancreatic carcinoma is essential for increasing patient survival rates. In this study, 52 patients with suspected pancreatic diseases were examined to investigate the value of K-ras codon 12 point mutation, levels of carcinoembryonic antigen (CEA) and carbohydrate antigen (CA19-9), and cytology of pancreatic juice in the diagnosis of pancreatic carcinoma. Pancreatic juice was taken without secretin stimulation. K-ras mutation was detected by enriched polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP). K-ras mutation in pancreatic juice was more frequent in carcinoma than in benign diseases (P = 0.0448). The positive predictive value of K-ras mutation for the diagnosis of neoplastic disease was 83%. The CEA level in pancreatic juice in carcinoma was significantly greater than that in benign disease (P< 0.0001). When the cutoff level of CEA was set at 50 ng/ml, its accuracy for the diagnosis of carcinoma was 85%. A multivariate analysis showed that K-ras mutation and CEA level in pancreatic juice, as well as serum CA19-9 level and age of the patient were independent variables for the diagnosis of carcinoma, and the accuracy of diagnosis by this analysis was increased to 90%. In conclusion, both K-ras mutation and CEA level in pancreatic juice may be valuable for the diagnosis of carcinoma. Better discrimination was possible with a multivariate analysis.


Assuntos
Biomarcadores Tumorais/análise , Antígeno Carcinoembrionário/análise , Carcinoma/diagnóstico , Genes ras , Neoplasias Pancreáticas/diagnóstico , Mutação Puntual , Adulto , Idoso , Sequência de Bases , Carcinoma/genética , Carcinoma/patologia , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Suco Pancreático/química , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Valor Preditivo dos Testes , Probabilidade , Prognóstico , Sensibilidade e Especificidade , Estatísticas não Paramétricas
20.
No Shinkei Geka ; 28(4): 367-71, 2000 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-10769836

RESUMO

We report herein the case of a 56-year-old woman who presented with repeated transient ischemic attacks (TIAs). Cerebral angiography revealed that the left redundant internal carotid artery (ICA) uncharacteristically curved medially. These findings were highly suggestive of an internal carotid artery aneurysm at the level between the first and second cervical vertebral bodies. The lesion was presumed to be difficult to access by the surgical procedure usually adopted in carotid endarterectomy. Thus, we decided to employ a modified vertical mandibular osteotomy. The operative view revealed that the lesion was atherosclerotic stenosis with ulceration, so carotid endarterectomy was indicated. This mandibular osteotomy not only provided us with wide, satisfactory exposure of the distal cervical internal carotid artery but also afforded good mandibular stability during the postoperative period.


Assuntos
Doenças das Artérias Carótidas/cirurgia , Artéria Carótida Interna , Mandíbula/cirurgia , Osteotomia/métodos , Doenças das Artérias Carótidas/complicações , Endarterectomia/métodos , Feminino , Humanos , Ataque Isquêmico Transitório/etiologia , Pessoa de Meia-Idade
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