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2.
J Clin Neurosci ; 34: 63-69, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27692502

RESUMO

Intraoperative rerupture (IOR) during clipping of cerebral aneurysms is a difficult complication of microneurosurgery. The aim of this study was to evaluate the incidence of IOR and analyze the strategies for controlling profound hemorrhage. A total of 165 patients with unruptured intracranial aneurysms and 46 patients with subarachnoid hemorrhage (SAH) treated surgically between April 2010 and March 2011, were reviewed. The data were collected with regard to age, sex, presence of symptoms, confounding factors and strategy for controlling intraoperative hemorrhage was analyzed in terms of location of aneurysms, timing of rupture and severity of IOR. 211 patients with 228 aneurysms were treated in this series. There were a total of six IORs which represented an IOR rate of 2.84% per patient and 2.63% per aneurysm. The highest ruptures rates occurred in patients with internal carotid artery aneurysms (25%). Surgeries in the group with ruptured aneurysms had a much higher rate of IOR compared with surgeries in the group with unruptured aneurysms. Of the six IOR aneurysms, one occurred during predissection, four during microdissection and one during clipping. One was major IOR, three were moderate and two were minor. Intraoperative rupture of an intracranial aneurysm can be potentially devastating in vascular neurosurgery. Aneurysm location, presence of SAH and surgical experience of the operating surgeon seem to be important factors affecting the incidence of IOR.


Assuntos
Aneurisma Roto/etiologia , Aneurisma Roto/cirurgia , Aneurisma Intracraniano/cirurgia , Complicações Intraoperatórias/cirurgia , Procedimentos Neurocirúrgicos/métodos , Adulto , Idoso , Aneurisma Roto/diagnóstico por imagem , Angiografia Digital , Procedimentos Endovasculares , Feminino , Humanos , Imageamento Tridimensional , Incidência , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/diagnóstico por imagem , Hemorragias Intracranianas/etiologia , Hemorragias Intracranianas/cirurgia , Complicações Intraoperatórias/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/terapia , Hemorragia Subaracnóidea/diagnóstico por imagem , Hemorragia Subaracnóidea/etiologia , Hemorragia Subaracnóidea/cirurgia , Transtornos da Visão/etiologia , Transtornos da Visão/terapia
3.
J Clin Neurosci ; 22(1): 69-72, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25443084

RESUMO

We present our experience with elective microsurgical clipping of unruptured intracranial aneurysms (UIA) and analyze this management. A total of 150 patients with UIA were reviewed and data were collected with regard to age, sex, presence of symptoms, location and size of the aneurysms, surgical complications and postoperative 1 year outcomes. Aneurysm size was assessed either by three-dimensional CT angiography or digital subtraction angiogram. Glasgow Outcome Scale was used to assess clinical outcomes. One hundred and fifty patients with 165 aneurysms were treated in this series. The mean size of the UIA was 5.6mm. Eighty aneurysms (48.5%) were less than 5mm in size, and 73 (44.2%) were from 5 to 10mm. Ten (6.1%) of the aneurysms were large and two (1.2%) were giant. One hundred and forty-three were asymptomatic and seven were symptomatic before surgery. The outcome was good in 147 patients (98%), and only three patients (2%) had a treatment-related unfavorable outcome. Five patients experienced transient neurological deficits and one patient experienced permanent neurological deficits. Overall 98.7% of the treated aneurysms were satisfactorily obliterated. Wound complications were seen only in three patients. In conclusion, UIA pose a significant challenge for neurosurgeons, where a delicate balance between benefits and possible risks must be weighed. If the requisite expertise is available, they can be treated surgically with low morbidity and a good outcome at specialized neurovascular centers.


Assuntos
Aneurisma Intracraniano/cirurgia , Microcirurgia/métodos , Procedimentos Neurocirúrgicos/métodos , Adulto , Idoso , Feminino , Seguimentos , Humanos , Aneurisma Intracraniano/diagnóstico , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/efeitos adversos , Resultado do Tratamento
4.
Int J Immunogenet ; 40(4): 292-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23442056

RESUMO

Oral squamous cell carcinoma (OSCC) is a worldwide health problem because it is a great cause of cancer morbidity and mortality. The transforming growth factor-ß1 (TGF-ß1) is involved in the regulation of numerous immunomodulatory processes. Thus, the aim of this case-control study was to investigate the possible association between the TGF-ß1T869C polymorphism and oral cancer. The genomic DNA extracted from peripheral blood of 62 male smoker patients diagnosed with OSCC and 62 smokers without cancer was analysed. The C allele was significantly more prevalent in the oral cancer group than in the controls, and individuals carrying this allele had an estimated 2.73-fold greater relative risk of developing cancer compared with C allele noncarriers (OR = 2.73, 95% CI = 1.19-6.28). Although T allele was not statistically significant among the controls, considering the genotypic analysis, the TT homozygous genotype showed a protector effect in relation to oral cavity cancer (OR = 0.37, 95% CI = 0.16-0.84). Some clinicopathological features were also analysed for genotype distribution, and no significant differences were observed: tumour size (P > 0.70), nodal status (P > 0.10) and tumour stage (P > 0.70). This is the first report of a study assessing the importance of T869C TGF-ß polymorphism in oral cancer. It is known that the TGF-ß T869C variation results in a Leu10Pro substitution in the signal peptide sequence. Our results suggested that the C allele could increase TGF-ß secretion which suppresses antitumour immune responses and may affect the OSCC risk.


Assuntos
Carcinoma de Células Escamosas/genética , Neoplasias Bucais/genética , Fator de Crescimento Transformador beta1/genética , Adulto , Alelos , Sequência de Bases , Carcinoma de Células Escamosas/imunologia , Estudos de Casos e Controles , Frequência do Gene , Marcadores Genéticos , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Neoplasias Bucais/imunologia , Polimorfismo de Nucleotídeo Único , Sinais Direcionadores de Proteínas/genética , Análise de Sequência de DNA , Fumar
5.
Dis Esophagus ; 26(2): 148-53, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22458712

RESUMO

A strong association between inactive aldehyde dehydrogenase-2 (ALDH2) and risk of esophageal cancer has been demonstrated in East Asian drinkers. An alcohol flushing questionnaire asking about past and current tendency for facial flushing to occur after drinking a glass (≈180 mL) of beer predicts the presence of inactive ALDH2 among Japanese aged 40 years or older with a sensitivity and specificity of approximately 90%. We invented a health-risk appraisal (HRA) model that makes it possible to identify Japanese men who are at high risk for esophageal cancer based on their past and current alcohol flushing tendency, drinking, smoking, and intake of vegetables and fruits. Between 2008 and 2009, 2221 Japanese men aged 50 years or older filled out the HRA questionnaire before undergoing a screening examination by upper gastrointestinal endoscopy at five medical facilities. The endoscopic examination resulted in a diagnosis of esophageal cancer in 19 subjects, and 117 (5.27%) subjects had an HRA score ≥ 11. The proportion of subjects with an HRA score ≥ 11 was higher in the 50-69 age group (6.11-6.88%) than in 70-89 age group (2.84-2.86%). The esophageal cancer detection rate was 4.27% among the subjects with an HRA score ≥ 11 and only 0.67% among the other subjects. Based on a receiver operating characteristic curve analysis, when an HRA score of ≥ 9 was used for subjects aged 50-69 years and of ≥ 8 for those aged 70-89 years as the cutoff value to select individuals with a high risk for esophageal cancer, its sensitivity and false-positive rate was 52.6% and 15.2%, respectively, and the cancer detection rate was 2.91% in the high-risk group, as opposed to 0.48% in the other group. In conclusion, the high detection rates for esophageal cancer in the high-risk groups encouraged screening based on our HRA model in larger Japanese populations.


Assuntos
Técnicas de Apoio para a Decisão , Detecção Precoce de Câncer/métodos , Neoplasias Esofágicas/diagnóstico , Esofagoscopia , Programas de Rastreamento/métodos , Idoso , Idoso de 80 Anos ou mais , Aldeído Desidrogenase/genética , Aldeído-Desidrogenase Mitocondrial , Neoplasias Esofágicas/etiologia , Neoplasias Esofágicas/genética , Reações Falso-Positivas , Marcadores Genéticos , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Curva ROC , Medição de Risco , Fatores de Risco , Sensibilidade e Especificidade , Inquéritos e Questionários
6.
Surg Neurol Int ; 2: 42, 2011 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-21541008

RESUMO

OBJECTIVE: To evaluate the usefulness and limitations of the intraoperative near-infrared (NIR) indocyanine green videoangiography (ICG-VA) and analysis of fluorescence intensity in cerebrovascular surgery. METHODS: Forty-eight patients received ICG-VA during various surgical procedures from May 2010 to August 2010. Included among them were 45 cases of cerebral aneurysms and 3 cases of cerebral arteriovenous malformations (AVMs). The infrared fluorescence module integrated into the surgical microscope was used to visualize fluorescent areas in the surgical field. An integrated analytical visualization tool constantly analyzed the fluorescence video sequence and generated it in the form of an intensity diagram for objective interpretation. RESULTS: Overall, the procedure of ICG VA was done 158 times in 48 patients. There was no adverse effect of ICG dye. In cerebral aneurysm cases, the images obtained were of high resolution. In 4 cases, incomplete clipping was detected by ICG-VA and allowed suitable adjustment to completely obliterate the aneurysm. In 3 aneurysm cases, the intensity diagram of ICG VA provided valuable information. ICG-VA identified the feeding arteries, the draining veins, and nidus in all 3 AVM cases, which was confirmed by an immediate analysis of fluorescence intensity. CONCLUSIONS: ICG-VA provides high resolution images allowing real-time assessment of the blood flow in surgical field. The intensity analysis function, in addition, is a useful adjunct to improve the accuracy of the clipping and decrease the complication rates in cerebral aneurysm cases. In cerebral AVM cases, with the help of color map and intensity diagram function, the superficial feeders, drainers, and nidus can be identified easily.

7.
Minim Invasive Neurosurg ; 54(1): 1-4, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21506061

RESUMO

OBJECTIVE: The aim of this study was to present our experience with retrograde suction decompression in clipping of large and giant cerebral aneurysms and analyze its advantages and pitfalls. METHODS: A retrospective analysis of 27 patients with large and giant intracranial aneurysms treated by suction decompression assisted clipping between November 2005 and February 2010 was done. The surgical technique and the outcome of patients were reviewed. RESULTS: All aneurysms were successfully clipped, and postoperative 3-D CTA or DSA revealed no major branch occlusion or residual aneurysm. There was no surgical mortality in both giant and large aneurysm groups. CONCLUSION: Retrograde suction decompression is a successful adjunct to clipping of large and giant cerebral aneurysms.


Assuntos
Descompressão Cirúrgica/métodos , Aneurisma Intracraniano/cirurgia , Procedimentos Neurocirúrgicos/métodos , Instrumentos Cirúrgicos/estatística & dados numéricos , Procedimentos Cirúrgicos Vasculares/métodos , Adulto , Idoso , Descompressão Cirúrgica/instrumentação , Descompressão Cirúrgica/mortalidade , Feminino , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/patologia , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/instrumentação , Procedimentos Neurocirúrgicos/mortalidade , Radiografia , Estudos Retrospectivos , Sucção/instrumentação , Sucção/métodos , Sucção/mortalidade , Instrumentos Cirúrgicos/normas , Procedimentos Cirúrgicos Vasculares/instrumentação , Procedimentos Cirúrgicos Vasculares/mortalidade
8.
Mini Rev Med Chem ; 11(13): 1143-52, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22353223

RESUMO

Caveolae are highly enriched in numerous membrane-bound proteins and caveolin-1 is their major component. Caveolae and caveolin proteins are involved in a variety of cellular processes including lipid homeostasis, endocytosis, signal transduction, and tumorigenesis. Breast cancer is one of the most common cancers in women throughout the world. Clinical studies have shown that the correlation of caveolin-1 expression with tumor progression varies with tumor type. The data presented here extend the findings that caveolin-1 suppresses breast cancer but there are controversial studies. The potential function of caveolin-1 in scaffolding signaling factors also demonstrates the importance of its expression control and modulation, correlating with physiological or pathological conditions. Based on current research, this review presents the current understanding of their function and the involvement of caveolin-1 in breast cancer pathogenesis.


Assuntos
Neoplasias da Mama/metabolismo , Mama/metabolismo , Caveolina 1/metabolismo , Transformação Celular Neoplásica/metabolismo , Animais , Mama/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Cavéolas/metabolismo , Cavéolas/patologia , Caveolina 1/genética , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Transdução de Sinais
11.
Neurol Med Chir (Tokyo) ; 41(8): 415-8, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11561355

RESUMO

A 69-year-old woman was treated by local irradiation for a malignant lymphoma of the left parotid gland. Three years after the radiation therapy, magnetic resonance imaging revealed heterogeneously enhanced masses in the left temporal lobe and left cerebellum. Thallium-201 chloride single photon emission computed tomography (Tl-SPECT) revealed high uptake and [11C]methionine positron emission tomography (Met-PET) revealed moderate uptake in both masses. Stereotactic biopsy was performed. The histological diagnosis was radiation necrosis. She was treated with steroids. Neurosurgeons should be aware of the difficulty in differentiating tumor recurrence from radiation necrosis even with Tl-SPECT and Met-PET, and the importance of obtaining a histological diagnosis for radiation necrosis.


Assuntos
Cerebelo/efeitos da radiação , Lesões por Radiação/diagnóstico por imagem , Lobo Temporal/efeitos da radiação , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada de Emissão , Idoso , Radioisótopos de Carbono , Cerebelo/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Linfoma de Zona Marginal Tipo Células B/diagnóstico por imagem , Metionina , Necrose , Neoplasias Parotídeas/radioterapia , Radiografia , Medula Espinal/diagnóstico por imagem , Medula Espinal/efeitos da radiação , Lobo Temporal/diagnóstico por imagem , Radioisótopos de Tálio
12.
Urology ; 56(6): 1056, 2000 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-11113763

RESUMO

The hand-assist technique offers the urologic surgeon several advantages. The technique provides the novice laparoscopist a logical segue into minimally invasive surgery by literally allowing one hand to remain in the realm of open surgery. Hand-assist access affords the laparoscopist the use of tactile sensation and blunt manual dissection and retraction. We describe an additional benefit of the hand-assist technique. In clinical situations in which more than one procedure is required, a properly positioned hand-assist device will avoid the need for two large incisions. We present simultaneous hand-assisted laparoscopic radical nephrectomy and open radical prostatectomy performed through a single midline incision.


Assuntos
Músculos Abdominais/cirurgia , Laparoscopia/métodos , Nefrectomia/métodos , Prostatectomia/métodos , Procedimentos Cirúrgicos Urológicos/métodos , Adenocarcinoma/cirurgia , Anestesia Geral , Carcinoma de Células Renais/cirurgia , Comorbidade , Humanos , Neoplasias Renais/epidemiologia , Neoplasias Renais/cirurgia , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/cirurgia
13.
Gan To Kagaku Ryoho ; 26(3): 361-4, 1999 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-10065101

RESUMO

In February, 1996, a 73-year-old male with liver dysfunction was admitted to our hospital for further examination and treatment of liver tumor. The liver tumor was revealed by imaging examination, which was mainly in the S4-S8 of liver with a thrombus growing from the right anterior branch to the right branch of the portal vein, and from the right hepatic vein to the inferior vena cava and right atrium. The serum AFP and PIVKA-II levels were elevated to 3.610 ng/ml and 54 AU/ml, respectively. The patient was diagnosed as having hepatocellular carcinoma, and was treated by arterial administration of anticancer drugs (epirubicin hydrochloride, mitomycin C and carboplatin) and TAE. Though the main tumor (S4-S8 of liver) was reduced by TAE, the portal and atrial tumor thrombus did not respond. One month after TAE (20 May, 1996), the first arterial administration of Lipiodol-SMANCS was given, followed by 4 successive procedures with an interval of about 1.5 months (total dose 15 mg), resulting in remarkable tumor thrombus shrinkage and reduction of AFP levels to 80 ng/ml. This case shows that arterial administration of SMANCS may be one of the effective treatments for hepatocellular carcinoma, even with tumor thrombus of hepatic vein, IVC and right atrium.


Assuntos
Antineoplásicos/administração & dosagem , Carcinoma Hepatocelular/tratamento farmacológico , Óleo Iodado/administração & dosagem , Neoplasias Hepáticas/tratamento farmacológico , Anidridos Maleicos/administração & dosagem , Células Neoplásicas Circulantes , Poliestirenos/administração & dosagem , Zinostatina/análogos & derivados , Idoso , Carcinoma Hepatocelular/patologia , Átrios do Coração/patologia , Veias Hepáticas/patologia , Humanos , Infusões Intra-Arteriais , Neoplasias Hepáticas/patologia , Masculino , Invasividade Neoplásica , Veia Cava Inferior/patologia , Zinostatina/administração & dosagem
14.
J Mol Biol ; 286(4): 1137-45, 1999 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-10047487

RESUMO

The crystal structure of tobacco PR-5d, an antifungal thaumatin-like protein isolated from cultured tobacco cells, was determined at the resolution of 1.8 A. The structure consists of 208 amino acid residues and 89 water molecules with a crystallographic R-factor of 0.169. The model has good stereochemistry, with respective root-mean-square deviations from the ideal values for bond and angle distances of 0.007 A and 1.542 degrees. Of the homologous PR-5 proteins, only those with antifungal activity had a common motif, a negatively charged surface cleft. This cleft is at the boundary between domains I and II, with a bottom part consisting of a three-stranded antiparallel beta-sheet in domain I. The acidic residues located in the hollow of the cleft form the beta-sheet region. Sequence and secondary structure analyses showed that the amino acid residues comprising the acidic cleft of PR-5d are conserved among other antifungal PR-5 proteins. This is the first report on the high-resolution crystal structure of an antifungal PR-5 protein. This structure provides insight into the function of pathogenesis-related proteins.


Assuntos
Nicotiana/química , Proteínas de Plantas/química , Plantas Tóxicas , Edulcorantes , Sequência de Aminoácidos , Antifúngicos/química , Sequência Conservada , Cristalografia por Raios X , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica , Homologia de Sequência de Aminoácidos
15.
Bioorg Med Chem ; 6(10): 1935-53, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9839023

RESUMO

Phosphinic acid-, sulfoximine- and sulfone-based transition-state analogues were synthesized and evaluated as inhibitors of Escherichia coli gamma-glutamylcysteine synthetase. These compounds have a carboxyl function at the beta-carbon to the tetrahedral central hetero atom so as to mimic the carboxyl group of the attacking cysteine in the transition state. The phosphinic acid- and the sulfoximine-based compounds were found to be potent ATP-dependent inactivators, both showing a slow-binding kinetics with overall affinities and second-order inactivation rates of one to two orders of magnitude greater than those of L-buthionine (SR)-sulfoximine (L-BSO). The sulfone was a simple reversible inhibitor without causing ATP-dependent enzyme inactivation, but its affinity toward the enzyme was still five times greater than that of L-BSO, indicating that the beta-carboxyl function plays a key role in the recognition of the inhibitors by the enzyme. The sulfoximine with (S)-beta-carbon to the sulfur was synthesized stereoselectively, and the two diastereomers with respect to the chiral sulfur atom were separated as a cyclic sulfoximine derivative. The sulfoximine with R-configuration around the sulfur served as an extremely powerful ATP-dependent inactivator with an overall inhibition constant of 39 nM and an inactivation rate of 6750 M-1 s-1, which correspond to 1260-fold higher affinity and almost 1400-fold greater inactivation rate as compared with L-BSO. The sulfoximine with (S)-sulfur was a simple reversible inhibitor with an inhibition potency comparable to that of the sulfone. The synthesis and inhibition profile of the N-phosphoryl sulfoximine is also described.


Assuntos
Butiratos/síntese química , Butiratos/farmacologia , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Escherichia coli/enzimologia , Glutamato-Cisteína Ligase/antagonistas & inibidores , Compostos Organofosforados/síntese química , Compostos Organofosforados/farmacologia , Glutamato-Cisteína Ligase/metabolismo , Organofosfonatos/síntese química
16.
Protein Eng ; 11(6): 467-72, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9725625

RESUMO

LipB, lipase activator protein from Pseudomonas aeruginosa TE3285, specifically recovers the enzymatic activity of denatured inactive lipase. To find important amino acid residues of LipB in this reactivation, random mutagenesis using error-prone PCR was performed on a gene encoding the functional region of LipB. The resultant DNA library was introduced into the lipase expression system using Escherichia coli, and LipB mutants lacking lipase activity were selected by two screening procedures. First, on agar plates containing tributyrin as a substrate for lipase, single colonies lacking active lipase secretion were selected as clones missing the active LipB. Second, to exclude nonsense and frameshift mutants, the molecular size of LipB in the given clones was confirmed by Western blotting. From the selected mutants, of which multiple residues are replaced, five single-residue substituted mutants were newly prepared. Consequently, Y99C, Y99H, S102R and R115C mutants formed no detectable complex with the lipase and lost the in vitro reactivation activity. In the case of Y99C and R115C, their single cysteine residue formed the intermolecular disulfide bridge. Thus, Tyr99 and Arg115 are likely to exist on the molecular surface of LipB, and are candidates for residues that make direct interaction with the denatured lipase in the reactivation process.


Assuntos
Mutagênese , Pseudomonas aeruginosa/química , Transativadores/química , Transativadores/genética , Proteínas de Bactérias , Western Blotting , Ativação Enzimática/efeitos dos fármacos , Reativadores Enzimáticos , Escherichia coli/genética , Expressão Gênica , Lipase/metabolismo , Peso Molecular , Plasmídeos/genética , Reação em Cadeia da Polimerase , Desnaturação Proteica , Pseudomonas aeruginosa/genética , Relação Estrutura-Atividade , Transativadores/farmacologia , Triglicerídeos/metabolismo
17.
Biosci Biotechnol Biochem ; 62(7): 1455-7, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9720231

RESUMO

Incubation of Escherichia coli gamma-glutamylcysteine synthetase with L-glutamic acid gamma-monohydroxamate and ATP caused slow but irreversible inhibition of the enzyme, and more than 90% activity was lost in three days. The enzyme was not inactivated when ATP was absent or L-aspartic acid beta-monohydroxamate was substituted for L-glutamic acid gamma-monohydroxamate, suggesting that the inactivation process reflected a mechanism-based reaction of L-glutamic acid gamma-monohydroxamate and ATP.


Assuntos
Trifosfato de Adenosina/farmacologia , Inibidores Enzimáticos/farmacologia , Escherichia coli/enzimologia , Glutamato-Cisteína Ligase/antagonistas & inibidores , Glutamatos/farmacologia , Ácidos Hidroxâmicos/farmacologia , Aspartato Aminotransferases/antagonistas & inibidores , Fosforilação
18.
Biosci Biotechnol Biochem ; 62(5): 907-14, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-27392587

RESUMO

Aspergillus oryzae O-1018 (FERM P-15834) separated from industrial koji for brewing sake was found to produce five papain-inhibitory compounds in the culture supernatant. The five isolated inhibitors were named CPI-1 to CPI-5, and their structures were elucidated by spectroscopic analyses and chemical degradation. We determined the structures of CPI-2, CPI-3 and CPI-4 as 4-amino-1-[[N- [(2S, 3S)-3-trans-carboxyoxiran-2-carbonyl]-L-isoleucyl] amino]butane, 5-amino-1-[[N-[(2S, 3S)-3-trans-carboxyoxiran-2-carbonyl]-L-isoleucyl]amino]pentane and N (8)- [N-[(2S, 3S)-3-trans-carboxyoxiran-2-carbonyl]-L-isoleu-cyl]spermidine, respectively. We also confirmed by a degradation experiment that CPI-1 consisted of L-trans-epoxysuccinic acid, L-tyrosine and spermidine, and that CPI-5 was composed of L-trans-epoxysuccinic acid, L-phenylalanine and spermidine. Although CPI-4 was identified as kojistatin A,(1)) the other CPIs seemed to be novel compounds. All CPIs were cysteine protease-specific inhibitors with appreciable selectivity toward cathepsin B and L. The inhibition potency of CPIs against cysteine proteases was as high as or higher than that of E-64. In particular, CPI-2, -3 and -4 were ten times more effective than E-64 toward cathepsin B and L, and CPI-1 and -5 were about 100 times more inhibitory than E-64 toward cathepsin L.

19.
Plant Cell Physiol ; 38(7): 783-91, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9297844

RESUMO

Cultured tobacco cells accumulate several pathogenesis-related proteins. A neutral PR-5 protein, PR-5d, was purified to homogeneity from such cells. PR-5d has highly hydrophobic characteristics, but hydropathy analysis of its primary structure did not show a hydrophobic domain. In a series of bioassays, purified PR-5d showed inhibitory activity against several phytopathogenic and non-phytopathogenic fungi as do other members of the PR-5 protein family. To study the antifungal mechanism based on three dimensional structure of PR-5d, purified PR-5d was crystallized. The preliminary X-ray analysis of the crystal revealed that the crystals belong to space group C2, with cell dimensions a = 80.2 A, b = 63.8 A, c = 45.7 A, and beta = 107.2 degrees, and diffract at least 1.8 A resolution.


Assuntos
Antifúngicos/química , Nicotiana/química , Proteínas de Plantas/química , Plantas Tóxicas , Edulcorantes , Sequência de Aminoácidos , Antifúngicos/farmacologia , Bioensaio , Células Cultivadas , Dicroísmo Circular , Cristalografia por Raios X , Dados de Sequência Molecular , Proteínas de Plantas/farmacologia , Análise de Sequência , Homologia de Sequência de Aminoácidos , Nicotiana/citologia
20.
Arch Biochem Biophys ; 339(1): 151-6, 1997 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-9056244

RESUMO

A derivative of glutathione synthetase (GSHase) with the multifunctional loop cleaved (nicked GSHase) was compared to both a deletion mutant of the loop (loopless GSHase) and wild-type with the intact loop (wild-type GSHase). The loop had been shown to be in a closed state in order to protect a catalytic intermediate and accelerate the reaction. Data indicated that cleavage of the loop resulted in a drastic decrease in glutathione synthetic activity which was similar to the results for the loop deletion. Kinetic analyses indicated that the manipulations of the loop impaired the substrate affinity, especially for glycine, and also catalytic efficiency. The nicked loop did not accelerate the reaction as fast as the intact loop; however, the catalytic intermediate was protected from hydrolysis by the cleaved loop as effectively as by the intact loop. These results suggest that the fragmental loop assumed the closed state. High concentrations of ATP showed some inhibitory effects on wild-type GSHase, while both nicked and loopless GSHase were not inhibited, indicating that the fragments of the nicked loop functioned independently. In conclusion, it is postulated that the two fragments of the nicked loop independently assumed the closed state to protect the catalytic intermediate and have lost the ability to accelerate glutathione synthesis.


Assuntos
Glutationa Sintase/química , Trifosfato de Adenosina/metabolismo , Proteínas de Bactérias/química , Sítios de Ligação , Escherichia coli/enzimologia , Glutationa/metabolismo , Cinética , Movimento (Física) , Conformação Proteica , Relação Estrutura-Atividade , Tripsina
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