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1.
Orthop Traumatol Surg Res ; 103(7): 1081-1085, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28827055

RESUMO

INTRODUCTION: Oncological margins and prognosis are the most important factors for operative planning of soft tissue sarcomas, but prediction of postoperative function is also necessary. The purpose of this study was to predict the knee flexion strength and postoperative function after knee flexor muscle resection for soft tissue sarcoma of the lower limbs. MATERIALS AND METHODS: Seventeen patients underwent knee flexor muscle resection for soft tissue sarcoma of the lower limbs between 1991 and 2015. The type of resected muscles was surveyed, knee flexion strength (ratio of affected to unaffected side) was evaluated using the Biodex System isokinetic dynamometer, and differences between the type of resected muscles were examined. The Musculoskeletal Tumor Society (MSTS) score, Toronto Extremity Salvage Score (TESS), European Quality of Life-5 Dimensions (EQ-5D), and Short Form 8 (SF-8) were used to assess postoperative function and examine correlations with flexion strength. The cutoff value for flexion strength to predict good postoperative results was calculated by a receiver operating characteristic (ROC) curve and Fisher's exact test. RESULTS: Median flexion strength decreased in the resection of sartorius (97.8%), gracilis (95.4%), gastrocnemius (85.2%; interquartile range (IQR): 85.0-86.2), medial hamstrings (semimembranosus and semitendinosus, 76.2%; IQR: 73.3-78.0), lateral hamstrings (long and short head of biceps femoris, 66.1%; IQR: 65.9-70.4), and bilateral hamstrings (27.3%; IQR: 26.6-31.5). A significant difference was observed between lateral and bilateral hamstrings resection (P=0.049). Flexion strength was associated with lower functional scales (MSTS score, P=0.021; TESS, P=0.008; EQ-5D, P=0.034). Satisfactory function was obtained at a flexion strength cutoff value of 65.7%, and strength remained above the cutoff value up to unilateral hamstrings resection. DISCUSSION: Greater knee flexor muscles resection can result in functional deficits that are associated with decreased flexion strength. If continuity of unilateral hamstrings is maintained, good postoperative results can be expected. LEVEL OF EVIDENCE: IV, retrospective study.


Assuntos
Joelho/cirurgia , Força Muscular , Músculo Esquelético/cirurgia , Recuperação de Função Fisiológica , Sarcoma/cirurgia , Neoplasias de Tecidos Moles/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Joelho/fisiopatologia , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/fisiopatologia , Qualidade de Vida , Curva ROC , Estudos Retrospectivos
2.
Bone Joint Res ; 5(6): 232-8, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27317788

RESUMO

OBJECTIVES: Our objective was to predict the knee extension strength and post-operative function in quadriceps resection for soft-tissue sarcoma of the thigh. METHODS: A total of 18 patients (14 men, four women) underwent total or partial quadriceps resection for soft-tissue sarcoma of the thigh between 2002 and 2014. The number of resected quadriceps was surveyed, knee extension strength was measured with the Biodex isokinetic dynamometer system (affected side/unaffected side) and relationships between these were examined. The Musculoskeletal Tumor Society (MSTS) score, Toronto Extremity Salvage Score (TESS), European Quality of Life-5 Dimensions (EQ-5D) score and the Short Form 8 were used to evaluate post-operative function and examine correlations with extension strength. The cutoff value for extension strength to expect good post-operative function was also calculated using a receiver operating characteristic (ROC) curve and Fisher's exact test. RESULTS: Extension strength decreased when the number of resected quadriceps increased (p < 0.001), and was associated with lower MSTS score, TESS and EQ-5D (p = 0.004, p = 0.005, p = 0.006, respectively). Based on the functional evaluation scales, the cutoff value of extension strength was 56.2%, the equivalent to muscle strength with resection of up to two muscles. CONCLUSION: Good post-operative results can be expected if at least two quadriceps muscles are preserved.Cite this article: A. Tanaka, Y. Yoshimura, K. Aoki, M. Kito, M. Okamoto, S. Suzuki, T. Momose, H. Kato. Knee extension strength and post-operative functional prediction in quadriceps resection for soft-tissue sarcoma of the thigh. Bone Joint Res 2016;5:232-238. DOI: 10.1302/2046-3758.56.2000631.

3.
Eur J Surg Oncol ; 41(3): 400-6, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25498358

RESUMO

AIMS: There is no consensus on the best surgical treatment for deep-seated atypical lipomatous tumor (ALT) of the extremities; furthermore, the appropriate duration for follow-up observation remains unclear. We investigated clinical and functional median-term outcomes in the primary operations for ALT of the extremities in order to find its best treatment methods and observation periods. METHODS: From 1996 to 2009, we diagnosed 41 patients with deep-seated ALT of the extremities. Wide resection was performed on 11 patients and marginal resection was performed on 30 patients. The minimum follow-up was 5 years (median, 8.5; range, 5-17.4). Patients were evaluated for their local recurrence, dedifferentiation, and post-operative function using the ISOLS/MSTS scoring system. RESULTS: Recurrence and dedifferentiation rates were both 0% for the wide resection group, while the rates were 23% (7/30) and 3% (1/30) for the marginal resection group, respectively. Median duration before recurrence was 7.2 years (range, 4.0-14.2). Local recurrence-free survival rate was significantly higher in the wide resection group (P = 0.013). In the marginal resection group, 10% (3/30) of the cases showed residual tumor. The localization of these tumors was all intermuscular. The ISOLS/MSTS scores were 98% (range, 90-100) for wide resection and 99% (range, 93-100) for marginal resection, with no statistical difference (P = 0.694). No ALT-related deaths occurred during the observation period. CONCLUSIONS: In addition to long-term (at least 8 years) of continuous observation, a wide resection is necessary in order to prevent recurrence, dedifferentiation, and residual tumor.


Assuntos
Lipoma/cirurgia , Lipossarcoma/cirurgia , Neoplasias de Tecidos Moles/cirurgia , Adulto , Idoso , Extremidades , Feminino , Humanos , Lipoma/patologia , Lipossarcoma/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias de Tecidos Moles/patologia , Resultado do Tratamento
4.
Appl Microbiol Biotechnol ; 72(1): 173-181, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16568315

RESUMO

Epsilon-poly-L-lysine (epsilon-PL) is one of the few naturally occurring biopolymers and is characterized by a peptide bond between the alpha-carboxyl and epsilon-amino groups. Previously, we purified and characterized the epsilon-PL-degrading enzyme (Pld) from Streptomyces albulus, which is an epsilon-PL producer, and this enzyme was expected to confer self-resistance to the epsilon-PL produced by the organism itself. The gene encoding Pld was cloned based on the N-terminal amino acid sequence determined in this study, and a sequencing analysis revealed eight open reading frames (ORFs), i.e., ORF1 to ORF8 in the flanking region surrounding the pld gene (present in ORF5). To investigate the biological function of Pld, we constructed a knockout mutant in which the pld gene is inactivated. Studies on epsilon-PL susceptibility, epsilon-PL-degrading activity, and epsilon-PL productivity demonstrated that the pld gene does play a partial role in self-resistance and that S. albulus was found to produce other epsilon-PL-degrading enzyme(s) in addition to Pld. To the best of our knowledge, this is the first report on a self-resistance gene for a biopolymer possessing antibacterial activity.


Assuntos
Antibacterianos/metabolismo , Peptídeo Hidrolases/metabolismo , Polilisina/metabolismo , Streptomyces/enzimologia , Sequência de Aminoácidos , Antibacterianos/farmacologia , Clonagem Molecular , DNA Bacteriano/química , DNA Bacteriano/genética , Deleção de Genes , Ordem dos Genes , Genes Bacterianos , Dados de Sequência Molecular , Fases de Leitura Aberta , Peptídeo Hidrolases/genética , Polilisina/farmacologia , Alinhamento de Sequência , Análise de Sequência de DNA , Análise de Sequência de Proteína , Streptomyces/genética
5.
Appl Microbiol Biotechnol ; 60(4): 442-8, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12466885

RESUMO

We constructed engineered CHO strains that can be used for high-level production of foreign proteins by gene-targeting. After transfecting dihydroforate reductase (DHFR)-deficient CHO cells with a plasmid carrying a loxP-green fluorescent protein (GFP) fusion gene and a DHFR gene, we screened colonies by fluorescent intensity. We selected 16 clones that expressed high levels of GFP and carried one copy of the plasmid in their chromosomes and treated them with methotrexate (MTX) to examine their ability for DHFR-mediated gene amplification. Two clones, MK1 and MK2, showed increased GFP expression upon gene amplification. In those clones, the loxP-GFP gene was integrated at a transcription-active, DHFR-mediated, gene-amplifiable locus in the chromosomes. A gene-targeting vector, carrying a loxP-fused hygromycin-resistance gene, was constructed to target desired genes in chromosomal loxP by Cre recombinase-mediated site-specific recombination. Using this cell-vector system, we could reproducibly obtain high producers of recombinant proteins by gene-targeting and gene amplification. In human monoclonal antibody production, after gene-targeting of loxP in MK2 and gene amplification with MTX, the MTX-resistant colonies showed high levels of antibody production. The most productive clone was able to produce 160 mg/l in 7 days in a low-protein medium in a spinner-flask.


Assuntos
Células CHO/fisiologia , Amplificação de Genes , Engenharia Genética/métodos , Plasmídeos/genética , Proteínas Recombinantes/biossíntese , Tetra-Hidrofolato Desidrogenase/biossíntese , Animais , Southern Blotting , Células CHO/enzimologia , Linhagem Celular , Cricetinae , Genes Reporter , Vetores Genéticos , Proteínas de Fluorescência Verde , Humanos , Integrases , Proteínas Luminescentes/metabolismo , Plasmídeos/química , Tetra-Hidrofolato Desidrogenase/genética , Transfecção , Proteínas Virais
6.
J Perinat Med ; 29(4): 357-9, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11565206

RESUMO

We describe a 4-month-old Japanese infant with West syndrome with gelastic seizures in clusters. Smile developed around 3 months and gradually increased in frequency and intensity. Positron emission tomography showed hypoperfusion in bilateral hypothalamus. Interictal electroencephalogram (EEG) showed hypsarrythmia. Simultaneous video/EEG monitoring was performed. At first, a smile-like episode developed every several seconds, gradually increased to an abrupt flexion of the neck and extremities, and gradually decreased to a smile-like episode at the end. Ictal EEG revealed desynchronization. ACTH was effective. Smiles are common emotional responses in infancy. However, EEG and neuroimaging should be considered in a case of perinatal asphyxia and delayed development.


Assuntos
Hemorragia/complicações , Doenças Hipotalâmicas/complicações , Espasmos Infantis/etiologia , Asfixia Neonatal/complicações , Eletroencefalografia , Feminino , Humanos , Lactente , Recém-Nascido , Imageamento por Ressonância Magnética , Espasmos Infantis/fisiopatologia , Tomografia Computadorizada de Emissão
7.
Biosci Biotechnol Biochem ; 65(5): 1071-5, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11440119

RESUMO

This study examined the effects of soybean beta-conglycinin, from which phytate was mostly removed, on the plasma lipids in young and adult rats. Male Wistar young (6 week-old) and adult (21 week-old) rats were fed high cholesterol diets containing 20% casein, soy protein isolate (SPI), or soybean beta-conglycinin for 10 days. In young rats, although the food intake of the beta-conglycinin group was higher than those of the casein and SPI groups, the weight gain was significantly lower than those of the other groups. However, in adult rats, the weight gain was not different among the groups. In young and adult rats, relative liver weights of SPI and beta-conglycinin groups were significantly lower than that of the casein group, and the degree of the reduction was more marked in the beta-conglycinin group than in the SPI group. In young rats, the plasma triglyceride level was significantly lower in the SPI and beta-conglycinin groups than that in the casein group. In addition, the plasma triglyceride level of the beta-conglycinin group was significantly lower than that of the SPI group. Plasma total cholesterol levels of the SPI and beta-conglycinin groups were significantly lower than that of the casein group. However, there was little difference in the lowering effect between SPI and beta-conglycinin. These results indicate that soybean beta-conglycinin may have lowering functions not only on plasma total cholesterol level, but also on plasma triglyceride level.


Assuntos
Envelhecimento/sangue , Globulinas/farmacologia , Glycine max/química , Ácido Fítico/isolamento & purificação , Proteínas de Soja , Triglicerídeos/sangue , Animais , Antígenos de Plantas , Masculino , Ratos , Ratos Wistar , Proteínas de Armazenamento de Sementes
8.
Biosci Biotechnol Biochem ; 65(4): 884-7, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11388468

RESUMO

A novel method for separating soybean beta-conglycinin and glycinin from defatted soymilk by a phytase treatment was developed. Phytase was added to defatted soymilk (1000FYT/100 g of protein) at pH 6.0, and the mixture incubated for 1 h at 40 degrees C. This procedure separated beta-conglycinin and glycinin without needing a reducing agent or cooling into the soluble and insoluble fractions, respectively. Simultaneously, most of the phytate in both proteins was removed.


Assuntos
6-Fitase/química , Globulinas/isolamento & purificação , Glycine max/química , Proteínas de Soja , Antígenos de Plantas , Eletroforese em Gel de Poliacrilamida , Proteínas de Armazenamento de Sementes
9.
Arch Biochem Biophys ; 386(2): 205-12, 2001 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-11368343

RESUMO

We have recently shown that 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, an endoplasmic reticulum (ER) membrane protein, is degraded in ER membranes prepared from sterol pretreated cells and that such degradation is catalyzed by a cysteine protease within the reductase membrane domain. The use of various protease inhibitors suggested that degradation of HMG-CoA reductase in vitro is catalyzed by a cathepsin L-type cysteine protease. Purified ER contains E-64-sensitive cathepsin L activity whose inhibitor sensitivity was well matched to that of HMG-CoA reductase degradation in vitro. CLIK-148 (cathepsin L inhibitor) inhibited degradation of HMG-CoA reductase in vitro. Purified cathepsin L also efficiently cleaved HMG-CoA reductase in isolated ER preparations. To determine whether a cathepsin L-type cysteine protease is involved in sterol-regulated degradation of HMG-CoA reductase in vivo, we examined the effect of E-64d, a membrane-permeable cysteine protease inhibitor, in living cells. While lactacystin, a proteasome-specific inhibitor, inhibited sterol-dependent degradation of HMG-CoA reductase, E-64d failed to do so. In contrast, degradation of HMG-CoA reductase in sonicated cells was inhibited by E-64d, CLIK-148, and leupeptin but not by lactacystin. Our results indicate that HMG-CoA reductase is degraded by the proteasome under normal conditions in living cells and that it is cleaved by cathepsin L leaked from lysosomes during preparation of the ER, thus clarifying the apparently paradoxical in vivo and in vitro results. Cathepsin L-dependent proteolysis was observed to occur preferentially in sterol-pretreated cells, suggesting that sterol treatment results in conformational changes in HMG-CoA reductase that make it more susceptible to such cleavage.


Assuntos
Acetilcisteína/análogos & derivados , Catepsinas/metabolismo , Cisteína Endopeptidases/metabolismo , Endopeptidases , Retículo Endoplasmático/metabolismo , Hidroximetilglutaril-CoA Redutases/metabolismo , Leucina/análogos & derivados , Esteróis/farmacologia , Acetilcisteína/farmacologia , Animais , Catepsina L , Catepsinas/antagonistas & inibidores , Catepsinas/isolamento & purificação , Extratos Celulares , Linhagem Celular , Permeabilidade da Membrana Celular , Cricetinae , Cisteína Endopeptidases/isolamento & purificação , Retículo Endoplasmático/enzimologia , Compostos de Epóxi/farmacologia , Concentração de Íons de Hidrogênio , Hidroximetilglutaril-CoA-Redutases NADP-Dependentes , Membranas Intracelulares/efeitos dos fármacos , Membranas Intracelulares/enzimologia , Membranas Intracelulares/metabolismo , Leucina/farmacologia , Lisossomos/enzimologia , Lisossomos/metabolismo , Complexos Multienzimáticos/antagonistas & inibidores , Complexos Multienzimáticos/metabolismo , Inibidores de Proteases/farmacologia , Complexo de Endopeptidases do Proteassoma , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Piridinas/farmacologia , Sonicação
11.
Jpn J Clin Oncol ; 30(7): 313-7, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11007165

RESUMO

We present a rare case of primary extracranial meningioma in a 36-year-old man, who had a solitary multinodular mass located in the plantar muscle of the foot. The histology of specimens from simple excision was typical of meningioma, showing bland spindle cell proliferation with a whorl pattern. Immunohistochemical analysis demonstrated that the tumor cells showed diffuse and strong positivity for epithelial membrane antigen as well as moderate reactivity for cytokeratin and vimentin. Ultrastructurally, the tumor cells were characterized by thin bipolar cytoplasmic processes and joined by multiple small desmosomes. There were frequent pinocytotic vesicles and a distinct external lamina on the cell surface. These findings suggest that this primary ectopic meningioma, arising in the soft tissue, may have been derived from perineurial cells of the peripheral nerve, but was morphologically distinguishable from perineurioma. Primary extracranial meningioma should be included in the differential diagnosis of soft-tissue spindle cell tumors, especially those of peripheral nerve origin.


Assuntos
Doenças do Pé/patologia , Meningioma/patologia , Neoplasias de Tecidos Moles/patologia , Adulto , Diagnóstico Diferencial , Humanos , Imuno-Histoquímica , Queratinas/análise , Masculino , Meningioma/ultraestrutura , Neoplasias de Bainha Neural/patologia , Neoplasias de Tecidos Moles/ultraestrutura , Vimentina/análise
12.
J Biochem ; 127(2): 211-20, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10731687

RESUMO

The accumulation and degradation in the endoplasmic reticulum (ER) of a truncated ER-60 protease, from which the C-terminal 89 amino acid residues have been deleted (K 417 ochre), was examined. K 417 ochre overexpressed in COS-1 cells is not secreted into the medium, but accumulates as insoluble aggregates in non-ionic detergent without degradation in unusual clump membrane structures. K 417 ochre, stably expressed, forms soluble aggregates in non-ionic detergent and is distributed in the reticular structures of ER. Under these conditions, K 417 ochre is not secreted into the medium but is degraded with a half-life time of more than 8 h. Since K 417 ochre/C all S, in which all the Cys residues of K 417 ochre are replaced by Ser, also forms aggregates, an inter-disulfide bond appears unnecessary for aggregation. In both types of aggregates, Ig heavy chain binding protein, calnexin, glucose regulated protein 94, calreticulin, ERp72, and protein disulfide isomerase are scarcely found. Since degradation of the stably expressed K 417 ochre was not inhibited by lactacystin, leupeptin, NH(4)Cl, or cytocharasin B, but was inhibited by N-acetyl-leucyl-leucyl-norleucinal, the self-aggregated abnormal protein in the lumen of ER is assumed to be degraded by an unknown protease system other than proteasome, lysosome or autophagy.


Assuntos
Cisteína Endopeptidases/metabolismo , Retículo Endoplasmático/metabolismo , Proteínas de Choque Térmico , Acetilcisteína/análogos & derivados , Acetilcisteína/farmacologia , Animais , Células COS/efeitos dos fármacos , Células COS/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Calnexina , Calreticulina , Proteínas de Transporte/metabolismo , Membrana Celular/metabolismo , Membrana Celular/ultraestrutura , Meios de Cultura , Cisteína Endopeptidases/efeitos dos fármacos , Cisteína Endopeptidases/genética , Inibidores de Cisteína Proteinase/farmacologia , Citocalasina B/farmacologia , Retículo Endoplasmático/efeitos dos fármacos , Chaperona BiP do Retículo Endoplasmático , Proteínas de Choque Térmico HSP70/metabolismo , Meia-Vida , Leupeptinas/farmacologia , Proteínas de Membrana/metabolismo , Chaperonas Moleculares/metabolismo , Isomerases de Dissulfetos de Proteínas/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Ribonucleoproteínas/metabolismo
13.
FEBS Lett ; 465(2-3): 145-7, 2000 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-10631322

RESUMO

ER-60 protease contains two CGHC motifs that appear to include an active site cysteine residue(s). Its proteolytic activity was lost with a double mutation of the C-terminal cysteines of the two motifs to alanine, but not with a single mutation of the C-terminal cysteine of either of the motifs to alanine. This suggests that these C-terminal cysteines independently constitute the catalytic active site. A mutation of both histidine residues in the two CGHC motifs to serine did not abolish the proteolytic activity, suggesting these histidine residues in the CGHC motifs do not constitute the catalytic dyad of ER-60 protease.


Assuntos
Cisteína Endopeptidases/metabolismo , Cisteína/metabolismo , Sequência de Aminoácidos , Domínio Catalítico , Cisteína Endopeptidases/química , Humanos , Dados de Sequência Molecular
14.
J Orthop Sci ; 5(5): 449-56, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11180901

RESUMO

The prognosis for malignant pelvic bone tumors is worse than that for malignant bone tumors of the extremities because definitive surgery in the pelvis is often difficult to accomplish. The results for eight patients who were treated consecutively with a multidisciplinary approach, from 1990, were analyzed. The histologic diagnosis was osteosarcoma in five patients, chondrosarcoma in two, and Ewing's sarcoma in one. Five lesions arose in the ilium and three in the pubis. The extraosseous tumors decreased in size and/or were encapsulated as a result of preoperative chemotherapy in six patients, four of these achieving a wide surgical margin. With respect to tumor location and surgical margin, all five lesions in the ilium involved the sacrum, four of these being resected with an inadequate margin. The three lesions in the pubis were resected with an adequate margin. Local recurrence was observed in two patients who had been treated with an inappropriate margin. During the period between 18 and 57 months after the first operation, five patients were continuously free of disease and one was still alive but had lung metastases. Our results indicate that a patient's chances of definitive surgery may be enhanced by a multidisciplinary approach, although the management of sacroiliac involvement remains challenging.


Assuntos
Neoplasias Ósseas/cirurgia , Osteossarcoma/cirurgia , Ossos Pélvicos , Adulto , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/tratamento farmacológico , Quimioterapia Adjuvante , Condrossarcoma/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Procedimentos de Cirurgia Plástica , Tomografia Computadorizada por Raios X
15.
Nagoya J Med Sci ; 62(1-2): 39-45, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10504826

RESUMO

Voltage-dependent calcium currents (ICa), which developed in cultured human neuroblastoma cells (NB-I), were studied using a whole-cell recording technique. Three types (T-, N- and L-type) of ICa were identified based on their biological and pharmacological properties. The T-type ICa was observed in about 60% of the cells from day 2 to day 12 and in about 20% after day 14. Likewise, the amplitude gradually decreased from -61.7 +/- 10.1 pA on day 2 to -18.3 +/- 9.1 pA on day 18. The N-type ICa appeared on day 6, with the number of cells exhibiting this current increasing up to 90.9% (-73.4 +/- 16.0 pA) on day 14 and immediately decreasing thereafter. The L-type ICa was observed in 50.0% of the cells on day 2, increasing to 84.6% of the cells on day 6 and remaining thereafter, while the amplitude gradually increased from -37.8 +/- 14.0 pA on day 2 to -158.8 +/- 22.8 pA on day 18, and decreased thereafter. These findings indicate that the expression of the voltage-dependent Ca2+ channels is strongly regulated by the developmental stage of the cell.


Assuntos
Canais de Cálcio/fisiologia , Neuroblastoma/fisiopatologia , Células Cultivadas , Humanos , Neuroblastoma/patologia , Técnicas de Patch-Clamp
16.
J Biochem ; 125(6): 1077-85, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10348910

RESUMO

Diacylglycerol lipase (DGL) was solubilized from human platelet microsomes with heptyl-beta-D-thioglucoside, and purified to homogeneity on SDS-PAGE using a combination of chromatographic and electrophoretic methods. The molecular mass of the purified DGL was estimated to be 33 kDa. Its apparent pI was pH 6.0, as determined by Immobiline isoelectro-focusing. The enzymatic activity of the partially purified DGL was investigated in the presence of a variety of inhibitors and reagents, as well as its pH and calcium dependence. Thiol reagents such as p-chloromercurubenzoic acid (pCMB), N-ethylmaleimide (NEM), and HgCl2 inhibited the activity, while dithiothreitol (DTT) and reduced glutathione (GSH) enhanced it. In addition, the enzymatic activity was inhibited by two serine blockers, phenylmethylsulfonyl fluoride (PMSF) and diisopropyl fluorophosphate (DFP), and by a histidine modifying reagent, p-bromophenacyl bromide (pBPB). These results suggest that cysteine, serine and histidine residues are required for the enzymatic activity of DGL. DGL was optimally active in the pH range of 7-8 and its activity did not change significantly in the presence of various calcium concentrations, even in the presence of 2 mM EGTA. This indicates that DGL can hydrolyze substrates with a basal cytosolic free Ca2+ level in the physiological pH range. A DGL inhibitor, RHC-80267, inhibited DGL activity in a dose-dependent manner with an IC50 (the concentration required for 50% inhibition) of about 5 microM. Unexpectedly, several phospholipase A2 (PLA2) inhibitors were potent inhibitors of DGL activity (IC50<5 microM), suggesting that the catalytic mechanisms of DGL and PLA2 may be similar. Finally, we show that DGL activity was inhibited by 2-monoacylglycerols (2-MGs), the reaction products of this enzyme. Among the three 2-MGs tested (2-arachidonoyl glycerol, 2-stearoyl glycerol, and 2-oleoyl glycerol), 2-arachidonoyl glycerol was the most potent inhibitor.


Assuntos
Plaquetas/enzimologia , Lipase Lipoproteica/isolamento & purificação , Domínio Catalítico , Detergentes , Inibidores Enzimáticos/farmacologia , Humanos , Técnicas In Vitro , Ponto Isoelétrico , Lipase Lipoproteica/sangue , Lipase Lipoproteica/química , Microssomos/enzimologia , Peso Molecular , Solubilidade
17.
Biosci Biotechnol Biochem ; 63(3): 610-3, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10227155

RESUMO

Protein disulfide isomerase (PDI) and its degradation products were found in HepG2, COS-1, and CHO-K1 cells. Whether or not the products were formed through autodegradation of PDI was examined, since PDI contains the CGHC motif, which is the active center of proteolytic activity in ER-60 protease. Commercial bovine PDI was autodegraded to produce a trimmed PDI. In addition, human recombinant PDI also had autodegradation activity. Mutant recombinant PDIs with CGHC motifs of which cysteine residues were replaced with serine or alanine residues were prepared. However, they were not autodegraded, suggesting the cysteine residues of motifs are necessary for autodegradation.


Assuntos
Isomerases de Dissulfetos de Proteínas/metabolismo , Animais , Células CHO , Células COS , Bovinos , Linhagem Celular , Cricetinae , Retículo Endoplasmático Liso/enzimologia , Humanos , Camundongos , Mutagênese Sítio-Dirigida , Isomerases de Dissulfetos de Proteínas/biossíntese , Isomerases de Dissulfetos de Proteínas/genética , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/isolamento & purificação
18.
Biochem Biophys Res Commun ; 257(3): 771-6, 1999 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-10208858

RESUMO

The growth of SW480 colon cancer cells following the transfection with the human interferon beta (hIFNbeta) gene entrapped in cationic multilamellar liposomes was effectively inhibited, but not that of the cells transfected with the gene from which the secretion signal sequence of hIFNbeta had been deleted. The amount of hIFNbeta secreted in the medium from SW480 cells transfected with hIFNbeta gradually increased and became maximum 3 days after the transfection, but no hIFNbeta was detected in the medium of the cells transfected with the secretion signal-deleted hIFNbeta. These findings indicate that the growth inhibition of SW480 cells after the transfection with hIFNbeta was caused by hIFNbeta secreted from the transfected cells. At that time, SW480 cells were induced to undergo apoptosis, which was identified by morphological aspects, viz., chromatin condensation, nuclear segmentation, and nucleosomal DNA fragmentation. The hIFNbeta-induced apoptosis was found to be linked to the activation of caspases 3 and 8 as evidenced by immunoblot, enzymological, and cell death inhibition analyses.


Assuntos
Apoptose , Neoplasias do Colo/patologia , Interferon beta/metabolismo , Apoptose/efeitos dos fármacos , Western Blotting , Caspase 3 , Caspase 8 , Caspase 9 , Inibidores de Caspase , Caspases/metabolismo , Divisão Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Tamanho Celular/efeitos dos fármacos , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Fragmentação do DNA , Ativação Enzimática , Humanos , Interferon beta/genética , Peso Molecular , Sinais Direcionadores de Proteínas/genética , RNA Mensageiro/metabolismo , Deleção de Sequência , Fatores de Tempo , Transfecção , Células Tumorais Cultivadas
19.
Biosci Biotechnol Biochem ; 63(2): 314-8, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10192912

RESUMO

The composition of nutritionally and physiologically important molecules in transgenic rice with the soybean glycinin gene was determined and compared with that of a non-transgenic control. Except for the levels of protein, amino acids and moisture, no marked differences were found between the two kinds of rice. The protein content of the transgenic rice was about 20% higher than the control (control, 6.5 g/100 g; transgenic, 8.0 g/100 g) with a concomitantly lower moisture content. This increased protein content mainly resulted from the increased glycinin expressed in the transgenic rice, and the protein was susceptible to gastric and intestinal digestion juices. In parallel with the increased protein content, some important amino acids lacking in quantity in normal rice were replenished.


Assuntos
Regulação da Expressão Gênica de Plantas , Globulinas/genética , Glycine max/química , Oryza/genética , Aminoácidos/análise , Western Blotting , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Digestão/fisiologia , Eletroforese em Gel de Poliacrilamida , Ácidos Graxos/análise , Engenharia Genética/normas , Globulinas/metabolismo , Minerais/análise , Oryza/química , Proteínas de Plantas/análise , Plantas Geneticamente Modificadas/química , Proteínas de Soja , Glycine max/genética , Espectrofotometria Atômica , Vitaminas/análise
20.
Biosci Biotechnol Biochem ; 63(11): 1942-6, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10635558

RESUMO

Feeding studies of transgenic potatoes with native and designed soybean glycinins in rats were done for four weeks. The designed glycinin has four additional methioninyl residues in the middle of the glycinin molecule. Rats were divided into four groups fed (I) only a commercial diet, (II) the diet plus non-transgenic potatoes, (III) the diet plus transgenic potatoes with native glycinin, and (IV) the diet plus transgenic potatoes with designed glycinin. Rats were fed 2,000 mg/kg-weight potatoes every day by oral administration. During the period tested, rats in each group (groups II, III, and IV) grew well without marked differences in appearance, food intake, body weight, or in cumulative body weight gain. No significant differences were also found in blood count, blood composition, and in internal organ weights among the rats after feeding potatoes (groups II, III, and IV) for four weeks. Necropsy at the end of experiment indicated neither pathologic symptoms in all rats tested nor histopathological abnormalities in liver and kidney. Judging from these results, the transgenic potatoes with glycinins are confirmed to have nearly the same nutritional and biochemical characteristics as non-transgenic one.


Assuntos
Ração Animal , Globulinas/genética , Glycine max/genética , Plantas Geneticamente Modificadas , Solanum tuberosum , Animais , Contagem de Células Sanguíneas , Peso Corporal , Ingestão de Energia , Masculino , Tamanho do Órgão , Ratos , Ratos Endogâmicos , Segurança , Solanum tuberosum/genética , Proteínas de Soja , Aumento de Peso
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