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1.
J Clin Biochem Nutr ; 67(1): 84-88, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32801473

RESUMO

In this study, we employed a previously developed in vivo assay system to determine whether the flowers and leaves of Syringa vulgaris (S. vulgaris; commonly known as "lilac") can prevent blood stasis syndrome, known as oketsu in Japanese. This syndrome is considered an important pathology in traditional Chinese and Japanese medicine, and is related to diseases such as peripheral vascular disorders, blood vessel inflammation, and platelet aggregation, whose severities are augmented owing to lipid peroxidation, free radicals, and oxidative stress. The assay system employed in this study monitored the blood flow decrease in the tail vein of mice subjected to sensitization with hen egg white lysozyme. Through bioassay-guided fractionation of different S. vulgaris extracts, five polyphenols were isolated and identified. Among them, quercetine 3-glucoside, quercetin 3-rutinoside, and acteoside were identified as active compounds, as they significantly mitigated blood flow reduction. These findings indicate that the polyphenols obtained from S. vulgaris could be useful for preventing oketsu and improve the quality of life of individuals with disorders and diseases such as gynecopathy, cold sensitivity, poor circulation, allergy, and lifestyle-related diseases.

2.
Clin Nephrol ; 92(4): 174-179, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31272526

RESUMO

INTRODUCTION: High-dose erythropoietin (EPO) administration to hemodialysis (HD) patients with EPO hyporesponsiveness, due to iron deficiency, hyperparathyroidism, malnutrition, inflammation, and inadequate HD, results in increased risk of mortality and cardiovascular events. We investigated the relationship of the EPO dose requirement with 4-, 5-, and 6-hour HD treatment times. MATERIALS AND METHODS: This cross-sectional study enrolled 300 HD patients, including those on 4-hour HD (n = 78), 5-hour HD (n = 106), and 6-hour HD (n = 116). We studied the following parameters: weekly EPO dose, hemoglobin (Hb), serum ferritin, Kt/V, membrane surface area, quantity of blood flow, quantity of dialysate flow, age, HD vintage, serum albumin, C-reactive protein (CRP), intact parathyroid hormone (iPTH), and ß2-microglobulin. These parameters were analyzed with JMP9TM statistical software. FINDINGS: The EPO requirement (units per week) of the 6-hour HD group (4,035 ± 269) was significantly lower than that of the 5-hour HD group (6,628 ± 630), which was significantly lower than that of the 4-hour HD group (8,567 ± 684). The Hb level, mean corpuscular volume, quantity of blood flow, quantity of dialysate flow, age, gender, ratio of diabetic patients, body mass index, dry weight, CRP, iPTH, use of antiplatelet agents and anticoagulants were not significantly different among the three groups. Multiple regression analysis with the weekly EPO requirement as the dependent variable showed HD treatment time (p < 0.0001) and CRP level (p < 0.001) as the significant independent variables. DISCUSSION: The EPO dose can be reduced by ~ 2,000 U/week by extending the HD treatment time for 1 hour; annual cost savings were calculated to be USD 570 per patient.


Assuntos
Eritropoetina/administração & dosagem , Diálise Renal , Idoso , Proteína C-Reativa/análise , Estudos Transversais , Feminino , Humanos , Falência Renal Crônica/sangue , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Diálise Renal/métodos , Fatores de Tempo
3.
J Biochem ; 162(4): 287-294, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28460043

RESUMO

Mitochondrial dynamic by frequent fusion and fission have important roles in various cellular signalling processes and pathophysiology in vivo. However, the molecular mechanisms that regulate mitochondrial fusion, especially in mammalian cells, are not well understood. Accordingly, we developed a novel biochemical cell-free mitochondrial fusion assay system using isolated human mitochondria. We used a protease and its specific substrate that are essential for yeast autophagy; Atg4 protease is required for maturation and the de-conjugation of the ubiquitin-like modifier Atg8. Atg4-FLAG and Atg8-GFP were separately expressed in the mitochondrial matrix of HeLa cells. Isolated mitochondria were then mixed and packed in the presence of energy regeneration mix. Immunoblotting with an anti-GFP antibody revealed Atg8 processing, suggesting that the double membranes of isolated mitochondria were indeed fused. The mitochondrial fusion reaction required GTP hydrolysis, mitochondrial membrane potential and intact outer membrane proteins containing two mitofusin isoforms. Using this assay, we searched for stimulators of mitochondrial fusion and found that rabbit reticulocyte lysate and Ca2+ chelator EGTA stimulate mitochondrial fusion. This novel cell-free assay system using isolated human mitochondria is simple, sensitive and reproducible; thus, it is useful for screening proteins and molecules that modulate mitochondrial fusion.


Assuntos
Cálcio/metabolismo , GTP Fosfo-Hidrolases/metabolismo , Fusão de Membrana , Mitocôndrias/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Membranas Mitocondriais/metabolismo , Proteínas Mitocondriais/metabolismo , Peptídeo Hidrolases/metabolismo , Cálcio/farmacologia , Sistema Livre de Células , GTP Fosfo-Hidrolases/antagonistas & inibidores , Células HeLa , Humanos , Immunoblotting , Proteínas de Transporte da Membrana Mitocondrial/antagonistas & inibidores , Proteínas Mitocondriais/antagonistas & inibidores , Células Tumorais Cultivadas
4.
Genes Cells ; 22(5): 452-471, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28397381

RESUMO

Ribosomes routinely prepared from Escherichia coli strain K12 contain intact (70 amino acids) and short (62 amino acids) forms of ribosomal protein L31. By contrast, ribosomes prepared from ompT mutant cells, which lack protease 7, contain only intact L31, suggesting that L31 is cleaved by protease 7 during ribosome preparation. We compared ribosomal subunit association in wild-type and ompT - strains. In sucrose density gradient centrifugation under low Mg2+ , 70S content was very high in ompT - ribosomes, but decreased in the wild-type ribosomes containing short L31. In addition, ribosomes lacking L31 failed to associate ribosomal subunits in low Mg2+ . Therefore, intact L31 is required for subunit association, and the eight C-terminal amino acids contribute to the association function. In vitro translation was assayed using three different systems. Translational activities of ribosomes lacking L31 were 40% lower than those of ompT - ribosomes with one copy of intact L31, indicating that L31 is involved in translation. Moreover, in the stationary phase, L31 was necessary for 100S formation. The strain lacking L31 grew very slowly. A structural analysis predicted that the L31 protein spans the 30S and 50S subunits, consistent with the functions of L31 in 70S association, 100S formation, and translation.


Assuntos
Proteínas de Escherichia coli/metabolismo , Peptídeo Hidrolases/metabolismo , Proteínas Ribossômicas/metabolismo , Subunidades Ribossômicas/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Peptídeo Hidrolases/genética , Ligação Proteica , Biossíntese de Proteínas , Proteólise , Proteínas Ribossômicas/química , Proteínas Ribossômicas/genética , Subunidades Ribossômicas/química
5.
Genes Cells ; 21(5): 408-24, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26935475

RESUMO

Mitochondrial morphology is dynamically regulated by fusion and fission. Several GTPase proteins control fusion and fission, and posttranslational modifications of these proteins are important for the regulation. However, it has not been clarified how the fusion and fission is balanced. Here, we report the molecular mechanism to regulate mitochondrial morphology in mammalian cells. Ablation of the mitochondrial fission, by repression of Drp1 or Mff, or by over-expression of MiD49 or MiD51, results in a reduction in the fusion GTPase mitofusins (Mfn1 and Mfn2) in outer membrane and long form of OPA1 (L-OPA1) in inner membrane. RNAi- or CRISPR-induced ablation of Drp1 in HeLa cells enhanced the degradation of Mfns via the ubiquitin-proteasome system (UPS). We further found that UPS-related protein BAT3/BAG6, here we identified as Mfn2-interacting protein, was implicated in the turnover of Mfns in the absence of mitochondrial fission. Ablation of the mitochondrial fission also enhanced the proteolytic cleavage of L-OPA1 to soluble S-OPA1, and the OPA1 processing was reversed by inhibition of the inner membrane protease OMA1 independent on the mitochondrial membrane potential. Our findings showed that the distinct degradation systems of the mitochondrial fusion proteins in different locations are enhanced in response to the mitochondrial morphology.


Assuntos
GTP Fosfo-Hidrolases/metabolismo , Mitocôndrias/metabolismo , Dinaminas , Técnicas de Inativação de Genes , Células HeLa , Homeostase , Humanos , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Proteínas Mitocondriais/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Ubiquitinas/metabolismo
6.
J Biochem ; 158(3): 253-61, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25953913

RESUMO

The diazotrophic cyanobacterium Anabaena sp. strain PCC 7120 (A.7120) differentiates into specialized heterocyst cells that fix nitrogen under nitrogen starvation conditions. Although reducing equivalents are essential for nitrogen fixation, little is known about redox systems in heterocyst cells. In this study, we investigated thioredoxin (Trx) networks in Anabaena using TrxM, and identified 16 and 38 candidate target proteins in heterocysts and vegetative cells, respectively, by Trx affinity chromatography (Motohashi et al. (Comprehensive survey of proteins targeted by chloroplast thioredoxin. Proc Natl Acad Sci USA, 2001; 98: , 11224-11229)). Among these, the Fe-S cluster scaffold protein NifU that facilitates functional expression of nitrogenase in heterocysts was found to be a potential TrxM target. Subsequently, we observed that the scaffold activity of N-terminal catalytic domain of NifU is enhanced in the presence of Trx-system, suggesting that TrxM is involved in the Fe-S cluster biogenesis.


Assuntos
Anabaena/metabolismo , Proteínas de Bactérias/biossíntese , Tiorredoxinas/metabolismo , Anabaena/genética , Proteínas de Bactérias/genética , Cloroplastos/genética , Cloroplastos/metabolismo , Regulação Bacteriana da Expressão Gênica , Nitrogênio/metabolismo , Fixação de Nitrogênio/genética , Nitrogenase/genética , Tiorredoxinas/biossíntese
7.
Mol Cell Biol ; 35(1): 211-23, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25348719

RESUMO

Mitochondria are dynamic organelles, and their fusion and fission regulate cellular signaling, development, and mitochondrial homeostasis, including mitochondrial DNA (mtDNA) distribution. Cardiac myocytes have a specialized cytoplasmic structure where large mitochondria are aligned into tightly packed myofibril bundles; however, recent studies have revealed that mitochondrial dynamics also plays an important role in the formation and maintenance of cardiomyocytes. Here, we precisely analyzed the role of mitochondrial fission in vivo. The mitochondrial fission GTPase, Drp1, is highly expressed in the developing neonatal heart, and muscle-specific Drp1 knockout (Drp1-KO) mice showed neonatal lethality due to dilated cardiomyopathy. The Drp1 ablation in heart and primary cultured cardiomyocytes resulted in severe mtDNA nucleoid clustering and led to mosaic deficiency of mitochondrial respiration. The functional and structural alteration of mitochondria also led to immature myofibril assembly and defective cardiomyocyte hypertrophy. Thus, the dynamics of mtDNA nucleoids regulated by mitochondrial fission is required for neonatal cardiomyocyte development by promoting homogeneous distribution of active mitochondria throughout the cardiomyocytes.


Assuntos
DNA Mitocondrial/genética , Dinaminas/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Coração/embriologia , Mitocôndrias Cardíacas/metabolismo , Dinâmica Mitocondrial , Animais , Cardiomiopatia Dilatada/genética , Cardiomiopatia Dilatada/metabolismo , Células Cultivadas , Modelos Animais de Doenças , Camundongos , Camundongos Knockout , Microscopia Eletrônica , Proteínas Mitocondriais/metabolismo , Células Musculares/citologia , Miócitos Cardíacos/citologia , Consumo de Oxigênio , Espécies Reativas de Oxigênio/metabolismo
8.
PLoS One ; 9(10): e109123, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25302503

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC), the fifth most common cancer type and the third highest cause of cancer death worldwide, develops in different types of liver injuries, and is mostly associated with cirrhosis. However, non-alcoholic fatty liver disease often causes HCC with less fibrosis, and the number of patients with this disease is rapidly increasing. The high mortality rate and the pathological complexity of liver diseases and HCC require blood biomarkers that accurately reflect the state of liver damage and presence of HCC. METHODS AND FINDINGS: Here we demonstrate that a circulating protein, apoptosis inhibitor of macrophage (AIM) may meet this requirement. A large-scale analysis of healthy individuals across a wide age range revealed a mean blood AIM of 4.99 ± 1.8 µg/ml in men and 6.06 ± 2.1 µg/ml in women. AIM levels were significantly augmented in the younger generation (20s-40s), particularly in women. Interestingly, AIM levels were markedly higher in patients with advanced liver damage, regardless of disease type, and correlated significantly with multiple parameters representing liver function. In mice, AIM levels increased in response to carbon tetrachloride, confirming that the high AIM observed in humans is the result of liver damage. In addition, carbon tetrachloride caused comparable states of liver damage in AIM-deficient and wild-type mice, indicating no influence of AIM levels on liver injury progression. Intriguingly, certain combinations of AIM indexes normalized to liver marker score significantly distinguished HCC patients from non-HCC patients and thus could be applicable for HCC diagnosis. CONCLUSION: AIM potently reveals both liver damage and HCC. Thus, our results may provide the basis for novel diagnostic strategies for this widespread and fatal disease.


Assuntos
Carcinoma Hepatocelular/sangue , Neoplasias Hepáticas/sangue , Fígado/patologia , Receptores Depuradores/sangue , Adulto , Idoso , Animais , Proteínas Reguladoras de Apoptose , Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Adulto Jovem
9.
Curr Biol ; 24(20): 2451-8, 2014 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-25264261

RESUMO

Mitochondria are dynamic organelles that change their morphology by active fusion and fission in response to cellular signaling and differentiation. The in vivo role of mitochondrial fission in mammals has been examined by using tissue-specific knockout (KO) mice of the mitochondria fission-regulating GTPase Drp1, as well as analyzing a human patient harboring a point mutation in Drp1, showing that Drp1 is essential for embryonic and neonatal development and neuronal function. During oocyte maturation and aging, structures of various membrane organelles including mitochondria and the endoplasmic reticulum (ER) are changed dynamically, and their organelle aggregation is related to germ cell formation and epigenetic regulation. However, the underlying molecular mechanisms of organelle dynamics during the development and aging of oocytes have not been well understood. Here, we analyzed oocyte-specific mitochondrial fission factor Drp1-deficient mice and found that mitochondrial fission is essential for follicular maturation and ovulation in an age-dependent manner. Mitochondria were highly aggregated with other organelles, such as the ER and secretory vesicles, in KO oocyte, which resulted in impaired Ca(2+) signaling, intercellular communication via secretion, and meiotic resumption. We further found that oocytes from aged mice displayed reduced Drp1-dependent mitochondrial fission and defective organelle morphogenesis, similar to Drp1 KO oocytes. On the basis of these findings, it appears that mitochondrial fission maintains the competency of oocytes via multiorganelle rearrangement.


Assuntos
Dinaminas/metabolismo , Regulação da Expressão Gênica/fisiologia , Células da Granulosa/fisiologia , Oócitos/fisiologia , Folículo Ovariano/fisiologia , Ovulação/fisiologia , Envelhecimento , Animais , Cálcio , Dinaminas/genética , Feminino , Fertilidade , Células da Granulosa/citologia , Humanos , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Mitocôndrias/fisiologia , Oócitos/citologia
10.
Congenit Anom (Kyoto) ; 54(3): 150-61, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24666250

RESUMO

Historical control data on rodent developmental toxicity studies, performed between 1994 and 2010, were obtained from 19 laboratories in Japan, including 10 pharmaceutical and chemical companies and nine contract research organizations. Rats, mice, and hamsters were used for developmental toxicity studies. Data included maternal reproductive findings at terminal cesarean sections and fetal findings including the spontaneous incidences of external, visceral, and skeletal anomalies. No noticeable differences were observed in maternal reproductive data between laboratories. Inter-laboratory variations in the incidences of fetuses with anomalies appeared to be due to differences in the selection of observation parameters, observation criteria, classification of the findings, and terminology of fetal alterations. Historical control data are useful for the appropriate interpretation of experimental results and evaluation of the effects of chemical on reproductive and developmental toxicities.


Assuntos
Avaliação Pré-Clínica de Medicamentos/história , Animais , Grupos Controle , Cricetinae , Feminino , Crescimento e Desenvolvimento/efeitos dos fármacos , História do Século XX , História do Século XXI , Masculino , Camundongos , Gravidez , Ratos , Reprodutibilidade dos Testes , Projetos de Pesquisa
11.
J Cell Sci ; 126(Pt 1): 176-85, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23077178

RESUMO

In yeast, C-tail-anchored mitochondrial outer membrane protein Fis1 recruits the mitochondrial-fission-regulating GTPase Dnm1 to mitochondrial fission sites. However, the function of its mammalian homologue remains enigmatic because it has been reported to be dispensable for the mitochondrial recruitment of Drp1, a mammalian homologue of Dnm1. We identified TBC1D15 as a Fis1-binding protein in HeLa cell extracts. Immunoprecipitation revealed that Fis1 efficiently interacts with TBC1D15 but not with Drp1. Bacterially expressed Fis1 and TBC1D15 formed a direct and stable complex. Exogenously expressed TBC1D15 localized mainly in cytoplasm in HeLa cells, but when coexpressed with Fis1 it localized to mitochondria. Knockdown of TBC1D15 induced highly developed mitochondrial network structures similar to the effect of Fis1 knockdown, suggesting that the TBC1D15 and Fis1 are associated with the regulation of mitochondrial morphology independently of Drp1. These data suggest that Fis1 acts as a mitochondrial receptor in the recruitment of mitochondrial morphology protein in mammalian cells.


Assuntos
Proteínas Ativadoras de GTPase/metabolismo , Proteínas de Membrana/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Proteínas Ativadoras de GTPase/genética , Células HeLa , Humanos , Imunoprecipitação , Proteínas de Membrana/genética , Microscopia de Fluorescência , Proteínas Mitocondriais/genética , Ligação Proteica/genética , Ligação Proteica/fisiologia , Interferência de RNA
12.
Congenit Anom (Kyoto) ; 52(3): 155-61, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22925216

RESUMO

Historical control data on rabbit prenatal developmental toxicity studies, performed between 1994-2010, were obtained from 20 laboratories, including 11 pharmaceutical and chemical companies and nine contract laboratories, in Japan. In this paper, data were incorporated from a laboratory if the information was based on 10 studies or more. Japanese White rabbits and New Zealand White rabbits were used for prenatal developmental toxicity studies. The data included maternal reproductive findings at terminal cesarean sections and fetal findings including spontaneous incidences of morphological alterations. No noticeable differences between strains or laboratories were observed in the maternal reproductive and fetal developmental data. The inter-laboratory variations in the incidences of fetal external, visceral, and skeletal alterations seem to be due to differences in the selection of observation parameters, observation criteria, and classification of the findings, and terminology of fetal alterations.


Assuntos
Anormalidades Induzidas por Medicamentos/etiologia , Teratogênicos/toxicidade , Animais , Modelos Animais de Doenças , Feminino , Feto/anormalidades , Feto/efeitos dos fármacos , Gravidez , Coelhos
14.
Chem Biodivers ; 7(6): 1634-43, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20564677

RESUMO

During storage of shell eggs, an egg-white protein, ovalbumin is converted into a molecular species with higher thermostability (Delta T(m)=8 degrees), which is named as S-ovalbumin. Since the pH of egg white is raised to 9.5 in that process, particular chemical modifications could occur. Although any evidence for relationship between chemical modifications and the thermostabilization had not been established, our X-ray crystallographic model for S-ovalbumin demonstrated that three serine residues (S164, S236, and S320) might be in D-configuration. Then, whether these serine residues contribute to the thermostabilization in S-ovalbumin is investigated by protein-engineering approach. By alkaline treatment, S236G mutant was converted to a more thermostable form, as well as ovalbumin has been converted to S-ovalbumin. Hence, the Ser236 is regarded to have no contribution to S-ovalbumin formation. On the contrary, S164G and S320G did show accelerated conversion to thermostable forms in comparison with ovalbumin or wild-type recombinant protein. When these residues were replaced with valine, which has a slower racemization rate, Delta T(m) after alkaline treatment had become half of that for the wild-type recombinant ovalbumin. Therefore, the process of S-ovalbumin formation is deduced to consist of two steps, which is closely related to the two serine residues.


Assuntos
Ovalbumina/química , Serina/química , Substituição de Aminoácidos , Dicroísmo Circular , Cristalografia por Raios X , Concentração de Íons de Hidrogênio , Mutagênese Sítio-Dirigida , Ovalbumina/genética , Engenharia de Proteínas , Estabilidade Proteica , Estrutura Terciária de Proteína , Temperatura
15.
Nat Cell Biol ; 11(8): 958-66, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19578372

RESUMO

Mitochondrial morphology is dynamically controlled by a balance between fusion and fission. The physiological importance of mitochondrial fission in vertebrates is less clearly defined than that of mitochondrial fusion. Here we show that mice lacking the mitochondrial fission GTPase Drp1 have developmental abnormalities, particularly in the forebrain, and die after embryonic day 12.5. Neural cell-specific (NS) Drp1(-/-) mice die shortly after birth as a result of brain hypoplasia with apoptosis. Primary culture of NS-Drp1(-/-) mouse forebrain showed a decreased number of neurites and defective synapse formation, thought to be due to aggregated mitochondria that failed to distribute properly within the cell processes. These defects were reflected by abnormal forebrain development and highlight the importance of Drp1-dependent mitochondrial fission within highly polarized cells such as neurons. Moreover, Drp1(-/-) murine embryonic fibroblasts and embryonic stem cells revealed that Drp1 is required for a normal rate of cytochrome c release and caspase activation during apoptosis, although mitochondrial outer membrane permeabilization, as examined by the release of Smac/Diablo and Tim8a, may occur independently of Drp1 activity.


Assuntos
Desenvolvimento Embrionário/fisiologia , GTP Fosfo-Hidrolases/metabolismo , Proteínas Mitocondriais/metabolismo , Sinapses/enzimologia , Animais , Animais Recém-Nascidos , Western Blotting , Encéfalo/citologia , Encéfalo/embriologia , Encéfalo/metabolismo , Linhagem Celular , Células Cultivadas , Citocromos c/metabolismo , Embrião de Mamíferos/citologia , Embrião de Mamíferos/embriologia , Embrião de Mamíferos/metabolismo , Desenvolvimento Embrionário/genética , Feminino , Fibroblastos/citologia , Fibroblastos/metabolismo , Fibroblastos/ultraestrutura , GTP Fosfo-Hidrolases/genética , Imuno-Histoquímica , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica , Microscopia de Fluorescência , Mitocôndrias/enzimologia , Mitocôndrias/ultraestrutura , Proteínas Mitocondriais/genética , Neurônios/citologia , Neurônios/metabolismo , Sinapses/metabolismo , Sinapses/ultraestrutura , Fatores de Tempo
16.
Masui ; 58(6): 762-4, 2009 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-19522273

RESUMO

We report a 16-year-old woman with dentatorubral pallidoluysian atrophy (DRPLA) on a ketogenic diet. She was scheduled for dental treatment under general anesthesia. She was diagnosed as having DRPLA at the age of 10. Medication included clonazepam, chlordiazepoxide, ethosuximide, sodium valproate and piracetam. She had been placed on a ketogenic diet at the age of 15, and seizures decreased. Preoperative laboratory data were normal except for serum cholesterol level (228 mg x dl(-1)) and blood ketones (1.8 mmol x l(-1)) with the use of Medisense Xtra. General anesthesia was induced using thiamylal, vecuronium, sevoflurane and maintained with sevoflurane and nitrous oxide-oxygen. Fluid infusion employed Solita T1 (glucose content of 2.6%: total 150 ml). Operation and general anesthesia presented no problems. We continued to infuse Solita T1 (total 350ml) for about 4 hours postoperatively. Ketogenic diet and additional medicine were started after 5 hours postoperatively. We measured perioperative and postoperative BS and blood ketones with the use of Medisense Xtra. She recovered from anesthesia without any significant complication.


Assuntos
Anestesia Geral , Dieta Cetogênica , Epilepsias Mioclônicas Progressivas , Assistência Perioperatória , Adolescente , Epilepsia/etiologia , Epilepsia/terapia , Feminino , Humanos , Corpos Cetônicos/sangue , Corpos Cetônicos/urina , Monitorização Intraoperatória , Epilepsias Mioclônicas Progressivas/terapia
17.
Infect Immun ; 75(5): 2090-100, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17296756

RESUMO

Gingipains are cysteine proteinases that are responsible for the virulence of Porphyromonas gingivalis. Recent studies have shown that P. gingivalis is trapped within autophagic compartments of infected cells, where it promotes survival. In this study we investigated the role of gingipains in the intracellular trafficking and survival of this bacterium in human aortic endothelial cells and any possible involvement of these enzymes in the autophagic pathway. Although autophagic events were enhanced by infection with either wild-type (WT) P. gingivalis strains (ATCC 33277, 381, and W83) or an ATCC 33277 mutant lacking gingipains (KDP136), we have found that more than 90% of intracellular WT and KDP136 colocalized with cathepsin B, a lysosome marker, and only a few of the internalized cells colocalized with LC3, an autophagosome marker, during the 0.5- to 4-h postinfection period. This was further substantiated by immunogold electron microscopic analyses, thus implying that P. gingivalis evades the autophagic pathway and instead directly traffics to the endocytic pathway to lysosomes. At the late stages after infection, WT strains in phagolysosomes retained their double-membrane structures. KDP136 in these compartments, however, lost its double-membrane structures, representing a characteristic feature of its vulnerability to rupture. Together with the ultrastructural observations, we found that the number of intracellular viable WT cells decreased more slowly than that of KDP136 cells, thus suggesting that gingipains contribute to bacterial survival, but not to trafficking, within the infected cells.


Assuntos
Adesinas Bacterianas/metabolismo , Aorta/microbiologia , Cisteína Endopeptidases/metabolismo , Células Endoteliais/microbiologia , Fagossomos/microbiologia , Porphyromonas gingivalis , Aorta/citologia , Infecções por Bacteroidaceae/microbiologia , Catepsina B/metabolismo , Células Cultivadas , Endocitose , Cisteína Endopeptidases Gingipaínas , Humanos , Porphyromonas gingivalis/crescimento & desenvolvimento , Porphyromonas gingivalis/patogenicidade , Porphyromonas gingivalis/fisiologia
18.
Genome Res ; 16(5): 686-91, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16606699

RESUMO

Protein-protein interactions play key roles in protein function and the structural organization of a cell. A thorough description of these interactions should facilitate elucidation of cellular activities, targeted-drug design, and whole cell engineering. A large-scale comprehensive pull-down assay was performed using a His-tagged Escherichia coli ORF clone library. Of 4339 bait proteins tested, partners were found for 2667, including 779 of unknown function. Proteins copurifying with hexahistidine-tagged baits on a Ni2+-NTA column were identified by MALDI-TOF MS (matrix-assisted laser desorption ionization time of flight mass spectrometry). An extended analysis of these interacting networks by bioinformatics and experimentation should provide new insights and novel strategies for E. coli systems biology.


Assuntos
Escherichia coli K12/química , Proteínas de Escherichia coli/metabolismo , Proteoma/análise , Proteínas de Escherichia coli/química , Biblioteca Gênica , Histidina/química , Modelos Biológicos , Fases de Leitura Aberta , Proteômica , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
19.
Microbiology (Reading) ; 151(Pt 8): 2721-2735, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16079349

RESUMO

It has been shown that Escherichia coli cells with increased expression of the rpoE gene encoding sigma(E) exhibit enhanced cell lysis in early stationary phase. Further analysis of the lysis phenomenon was performed using a transient expression system of the rpoE gene and by DNA microarray. The former analysis revealed a sigma(E)-directed cell lysis, specific for early stationary phase but not for the exponential phase. The microarray analysis with RNAs from exponential and early stationary phase cells revealed that a large number of genes were up- or down-regulated when the rpoE gene was induced, and that several genes were induced in a phase-specific manner. The upregulated genes include many previously identified sigma(E) regulon genes, suggesting that a large number of genes are under the control of sigma(E) in this organism. These genes are involved in various cellular activities, including the cell envelope, cellular processes, regulatory functions, transport and translation. Genes that are presumably related to phase-specific cell lysis in E. coli are discussed.


Assuntos
Proteínas de Escherichia coli/fisiologia , Escherichia coli/crescimento & desenvolvimento , Regulação Bacteriana da Expressão Gênica , Fator sigma/fisiologia , Fatores de Transcrição/fisiologia , Escherichia coli/genética , Escherichia coli/metabolismo
20.
Genes Cells ; 10(5): 393-408, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15836769

RESUMO

Obg proteins belong to a subfamily of GTP binding proteins, which are highly conserved from bacteria to human. Mutations of obgE genes cause pleiotropic defects in various species but the function remained unclear. Here we examine the function of ObgE, the Obg homolog in Escherichia coli. The growth rate correlates with the amount of ObgE in cells. Co-fractionation experiments further suggest that ObgE binds to 30S and 50S ribosomal subunits, but not to 70S ribosome. Pull-down assays suggest that ObgE associates with several specific ribosomal proteins of 30S and 50S subunits, as well as RNA helicase CsdA. Purified ObgE cosediments with 16S and 23S ribosomal RNAs in vitro in the presence of GTP. Finally, mutation of ObgE affects pre-16Sr-RNA processing, ribosomal protein levels, and ribosomal protein modification, thereby significantly reducing 70S ribosome levels. This evidence implicates that ObgE functions in ribosomal biogenesis, presumably through the binding to rRNAs and/or rRNA-ribosomal protein complexes, perhaps as an rRNA/ribosomal protein folding chaperone or scaffold protein.


Assuntos
Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Ribossomos/metabolismo , Citosol/metabolismo , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Proteínas de Escherichia coli/genética , Imuno-Histoquímica , Proteínas Monoméricas de Ligação ao GTP/genética , Mutação , RNA Ribossômico 16S/metabolismo , RNA Ribossômico 23S/metabolismo , Temperatura , Fatores de Tempo
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