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1.
BMC Musculoskelet Disord ; 23(1): 493, 2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35614404

RESUMO

BACKGROUND: A spinal cord injury (SCI) is a devastating, life-changing event that has profoundly deleterious effects on an individual's health and well-being. Dysregulation of neuromuscular, cardiometabolic, and endocrine organ systems following an SCI contribute to excess morbidity, mortality and a poor quality of life. As no effective treatments currently exist for SCI, the development of novel strategies to improve the functional and health status of individuals living with SCI are much needed. To address this knowledge gap, the current study will determine whether a Home-Based Multimodality Functional Recovery and Metabolic Health Enhancement Program that consists of functional electrical stimulation of the lower extremity during leg cycling (FES-LC) plus arm ergometry (AE) administered using behavioral motivational strategies, and testosterone therapy, is more efficacious than FES-LC plus AE and placebo in improving aerobic capacity, musculoskeletal health, function, metabolism, and wellbeing in SCI. METHODS: This single-site, randomized, placebo-controlled, parallel group trial will enroll 88 community-dwelling men and women, 19 to 70 years of age, with cervical and thoracic level of SCI, ASIA Impairment Scale grade: A, B, C, or D, 6 months or later after an SCI. Participants randomized to the multimodality intervention will undergo 16 weeks of home-based FES-LC and AE training plus testosterone undecanoate. Testosterone undecanoate injections will be administered by study staff in clinic or by a visiting nurse in the participant's home. The control group will receive 16 weeks of home-based FES-LC and AE exercise plus placebo injections. The primary outcome of this trial is peak aerobic capacity, measured during an incremental exercise testing protocol. Secondary outcomes include whole body and regional lean and adipose tissue mass; muscle strength and power; insulin sensitivity, lipids, and inflammatory markers; SCI functional index and wellbeing (mood, anxiety, pain, life satisfaction and depressive symptoms); and safety. DISCUSSION: We anticipate that a multimodality intervention that simultaneously addresses multiple physiological impairments in SCI will result in increased aerobic capacity and greater improvements in other musculoskeletal, metabolic, functional and patient-reported outcomes compared to the control intervention. The findings of this study will have important implications for improving the care of people living with an SCI. TRIAL REGISTRATION: ClinicalTrials.gov :  ( NCT03576001 ). Prospectively registered: July 3, 2018.


Assuntos
Qualidade de Vida , Traumatismos da Medula Espinal , Adulto , Idoso , Terapia por Exercício/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/terapia , Resultado do Tratamento
2.
Phys Rev Lett ; 118(13): 137202, 2017 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-28409964

RESUMO

The defining problem in frustrated quantum magnetism, the ground state of the nearest-neighbor S=1/2 antiferromagnetic Heisenberg model on the kagome lattice, has defied all theoretical and numerical methods employed to date. We apply the formalism of tensor-network states, specifically the method of projected entangled simplex states, which combines infinite system size with a correct accounting for multipartite entanglement. By studying the ground-state energy, the finite magnetic order appearing at finite tensor bond dimensions, and the effects of a next-nearest-neighbor coupling, we demonstrate that the ground state is a gapless spin liquid. We discuss the comparison with other numerical studies and the physical interpretation of this result.

3.
Rev Sci Instrum ; 85(7): 076101, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25085186

RESUMO

We present a dynamic strain field mapping method based on synchrotron X-ray digital image correlation (XDIC). Synchrotron X-ray sources are advantageous for imaging with exceptional spatial and temporal resolutions, and X-ray speckles can be produced either from surface roughness or internal inhomogeneities. Combining speckled X-ray imaging with DIC allows one to map strain fields with high resolutions. Based on experiments on void growth in Al and deformation of a granular material during Kolsky bar/gas gun loading at the Advanced Photon Source beamline 32ID, we demonstrate the feasibility of dynamic XDIC. XDIC is particularly useful for dynamic, in-volume, measurements on opaque materials under high strain-rate, large, deformation.

4.
Bull Entomol Res ; 104(3): 383-92, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24702985

RESUMO

Temperature is a key environmental factor in determining the population size of Cnaphalocrocis medinalis in summer. High temperatures inhibit survival, development and fecundity of this insect. However, biological responses of female and male adults to heat shock, and physiological mechanism of high temperature suppressing population development are still ambiguous. We experimentally tested the impact of heat shock (5 h day-1) on biological traits, spermatogenesis and sperm transfer of adults of C. medinalis. The result showed that heat exposure to 39 and 40 °C for 5 h reduced longevity and copulation frequency of adults, and hatchability of eggs. Immediate survival rate of males was lower than that of females after 3 days of exposure to 41 °C. The oviposition period, copulation frequency, fecundity of adults and hatchability of eggs were significantly lower when male adults were exposed to 40 or 41 °C for 3 days. Heat shock decreased frequency and success rate of mating when males were exposed, and it also resulted in postponement of mating behaviour and prolongation of mating duration as both the female and male adults were exposed. Heat shock did not affect spermatogenesis, but significantly inhibited sperms maturation. Moreover, males could not ejaculate sperm into females during copulation when these male moths received heat shock. Heat shock remarkably suppressed mating behaviour and sperm transfer, which led to a dramatic decline of rice leaf folder populations.


Assuntos
Temperatura Alta , Mariposas/fisiologia , Comportamento Sexual Animal/fisiologia , Animais , China , Feminino , Longevidade , Masculino , Mariposas/crescimento & desenvolvimento , Ovário/crescimento & desenvolvimento , Ovário/fisiologia , Óvulo/fisiologia , Reprodução
5.
Cell Death Dis ; 5: e1109, 2014 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-24603337

RESUMO

Helicobacter pylori (H. pylori) infection is associated with chronic gastritis, peptic ulcer and gastric cancer. Apoptosis induced by microbial infections is implicated in the pathogenesis of H. pylori infection. Here we show that human gastric epithelial cells sensitized to H. pylori confer susceptibility to TRAIL-mediated apoptosis via modulation of death receptor signaling. Human gastric epithelial cells are intrinsically resistant to TRAIL-mediated apoptosis. The induction of TRAIL sensitivity by H. pylori is dependent on the activation of caspase-8 and its downstream pathway. H. pylori induces caspase-8 activation via enhanced assembly of the TRAIL death-inducing signaling complex (DISC) through downregulation of cellular FLICE-inhibitory protein (FLIP). Overexpression of FLIP abolished the H. pylori-induced TRAIL sensitivity in human gastric epithelial cells. Our study thus demonstrates that H. pylori induces sensitivity to TRAIL apoptosis by regulation of FLIP and assembly of DISC, which initiates caspase activation, resulting in the breakdown of resistance to apoptosis, and provides insight into the pathogenesis of gastric damage in Helicobacter infection. Modulation of host apoptosis signaling by bacterial interaction adds a new dimension to the pathogenesis of Helicobacter.


Assuntos
Apoptose/efeitos dos fármacos , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/metabolismo , Células Epiteliais/efeitos dos fármacos , Infecções por Helicobacter/microbiologia , Helicobacter pylori/patogenicidade , Estômago/efeitos dos fármacos , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/metabolismo , Caspase 8/metabolismo , Linhagem Celular Tumoral , Citocromos c/metabolismo , Proteínas Adaptadoras de Sinalização de Receptores de Domínio de Morte/metabolismo , Relação Dose-Resposta a Droga , Ativação Enzimática , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Células Epiteliais/patologia , Mucosa Gástrica/metabolismo , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Proteínas Recombinantes/farmacologia , Transdução de Sinais/efeitos dos fármacos , Estômago/microbiologia , Estômago/patologia , Fatores de Tempo
6.
Brain Imaging Behav ; 6(2): 208-23, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22684770

RESUMO

Traumatic brain injury results in a metabolic cascade of changes that occur at the molecular level, invisible to conventional imaging methods such as computed tomography or magnetic resonance imaging. Non-invasive metabolic imaging tools such as single photon emission computed tomography (SPECT), positron emission tomography (PET), and magnetic resonance spectroscopy (MRS) are the ideal methods for providing insight to these changes by measuring regional cerebral blood flow, glucose metabolism, and brain metabolite concentrations, respectively, after mild traumatic brain injury (mTBI). The purpose of this review is to provide an overview of the different methodologies and provide an up-to-date summary of recent findings with SPECT, PET, and MRS technologies, specifically after mTBI, as defined by standardized criteria. Given that the different physiological and pathological responses are heterogeneous, efforts will be made to separate studies at different time points after injury (acute, subacute, and chronic stages) as well as to the different types of mTBI such sports-related head injury where repetitive head injuries are much more common and may present a unique signature.


Assuntos
Lesões Encefálicas/diagnóstico por imagem , Lesões Encefálicas/metabolismo , Mapeamento Encefálico/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Neuroimagem Funcional/métodos , Tomografia Computadorizada de Emissão/métodos , Humanos
7.
Eur J Clin Invest ; 39(4): 296-303, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19292885

RESUMO

BACKGROUND: Previous reports have indicated that statins could prevent bone loss in ovariectomized (OVX) rats and increase the expressions of osteogenic genes in cultured osteoblasts. In this study, we hypothesized that simvastatin might increase osteoblast number and protein expressions of osteogenic markers localized in bones in concomitance with the prevention of bone loss in OVX rats. MATERIALS AND METHODS: Fifty-four 3-month-old OVX and sham-operated (SHAM) female Sprague-Dawley rats were used. Simvastatin (10-20 mg kg(-1) day(-1)) was administrated orally for 6 weeks. Trabecular volume, osteoblast number and osteogenic proteins including BMP2, collagen type I and osteocalcin on bone sections obtained from lumbar vertebral body, distal femur and proximal tibia were measured. RESULTS: The results showed that SHAM rats had significantly less trabecular bone volume and osteoblast number than that of OVX rats 6 weeks after operation. Oral simvastatin treatment (10-20 mg kg(-1) day(-1)) increased bone volume and osteoblast number in the distal femurs, proximal tibiae and vertebrae of OVX rats. Furthermore, the osteoblastic cells with immuno-stained BMP2, collagen type I and osteocalcin in vertebral bones were significantly increased by simvastatin treatment (20 mg kg(-1) day(-1)) in OVX rats. CONCLUSIONS: This study demonstrates that simvastatin enhances the production of osteogenic proteins in bone and this effect may contribute to the prevention of bone loss in OVX rats.


Assuntos
Densidade Óssea/efeitos dos fármacos , Proteínas Morfogenéticas Ósseas/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Sinvastatina/farmacologia , Análise de Variância , Animais , Modelos Animais de Doenças , Feminino , Ovariectomia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
8.
J Endocrinol Invest ; 27(1): 1-5, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15053235

RESUMO

Our previous study showed that estrogen stimulates membrane-type matrix metalloproteinases-1 (MT1-MMP) production in osteoblastic cells culture, but has no effect on MMP-2 and TIMP-2 synthesis. Osteoblast-derived MT1-MMP have been recently implied to play a role in bone metabolism by degrading tumor necrosis factor-alpha (TNF-alpha), resolving extracellular matrix and activating proMMP-2, which requires the process of activation mediated by MT1-MMP/tissue inhibitor of metalloproteinase (TIMP-2) complex on the cell surface. To investigate the mechanism of bone loss following estrogen deficiency, we examined the effects of estrogen on osteoblast synthesis of MT1-MMP, MMP-2 and TIMP-2. In situ hybridization and immunohistochemistry of rat bone samples were used to document the synthesis of MT1-MMP, MMP-2, and TIMP-2 mRNA and protein. Osteoblasts from distal femoral head showed an increase in the pattern of MT1-MMP mRNA and protein production in sham-operated controls and 17beta-estradiol (E2)-treated rats, compared with the ovariectomized group; the synthesis of MMP-2 and TIMP-2 mRNA and protein was unaffected. Our data show a down-regulation of MT1-MMP synthesis by osteoblast in vivo following estrogen withdrawal, and treatment with E2 resulted in induced MT1-MMP expression in vivo. There is evidence suggesting a role for MT1-MMP in the process of bone loss during the pathogenesis of osteoporosis.


Assuntos
Estradiol/fisiologia , Metaloendopeptidases/metabolismo , Osteoblastos/enzimologia , Osteoporose/fisiopatologia , Animais , Células Cultivadas , Regulação para Baixo , Feminino , Imuno-Histoquímica , Hibridização In Situ , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinases da Matriz Associadas à Membrana , Metaloendopeptidases/genética , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Inibidor Tecidual de Metaloproteinase-2/genética , Inibidor Tecidual de Metaloproteinase-2/metabolismo
9.
J Endocrinol Invest ; 26(11): 1111-6, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15008250

RESUMO

Our study previously showed that estrogen and progesterone stimulated the production of matrix metalloproteinase-14 [MMP-14, or also named membrane type matrix metalloproteinses-1 (MT1-MMP)] in osteoblastic cells. MMP-14 was implied to regulate the function of osteoblasts by degrading bone matrix or growth factors, but the mechanism is unclear. Since MMP-14 plays a role primarily through the catalytic domain, and truncated MMP-14 containing the catalytic domain and lacking transmembrane domain can be secreted into medium by cultured cells, our present study was performed to observe the direct effects of recombinant MMP-14 catalytic domain on cultured human osteoblastic osteogenic sarcoma (SaOS)-2 cells. Our data showed that recombinant MMP-14 catalytic domain activated proMMP-2 secreted into media by SaOS-2 cells, and this process was blocked by ethylenediamine tetraacetic acid (EDTA) treatment. Recombinant MMP-14 catalytic domain inhibited the adhesion of SaOS-2 cells to immobilized type I collagen or fibronectin in a dose-dependent manner, and these effects on SaOS-2 cells were abolished by EDTA. Recombinant MMP-14 catalytic domain induced SaOS-2 cells apoptosis in a dose-dependent manner, and apoptosis-inducing activity of MMP-14 catalytic domain was blocked if it was treated with EDTA. In conclusion, we revealed that recombinant MMP-14 catalytic domain induced SaOS-2 cells apoptosis. We also indirectly showed the activity of MMP-14 catalytic domain to degrade extracellular matrix (ECM) in cultures of SaOS-2 cells through Gelatin Zymograms and adhesion assay. This suggests that since adhesion of cells to ECM serves as a survival mechanism in osteoblasts, the catalytic activity of recombinant MMP-14 catalytic domain on matrix proteins contributes to its apoptosis-inducing activity.


Assuntos
Apoptose/efeitos dos fármacos , Metaloendopeptidases/farmacologia , Osteoblastos/efeitos dos fármacos , Apoptose/fisiologia , Western Blotting , Domínio Catalítico , Adesão Celular/efeitos dos fármacos , Adesão Celular/fisiologia , Linhagem Celular Tumoral , Ácido Edético/farmacologia , Humanos , Técnicas Imunoenzimáticas , Metaloproteinases da Matriz Associadas à Membrana , Metaloendopeptidases/antagonistas & inibidores , Metaloendopeptidases/metabolismo , Osteoblastos/citologia , Osteoblastos/enzimologia , Osteoblastos/metabolismo , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia
10.
Exp Cell Res ; 267(1): 28-36, 2001 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-11412035

RESUMO

Growth factor-dependent translocation of phospholipase C-gamma1 (PLC-gamma1) was investigated using a green fluorescent protein-tagged PLC-gamma1 (PLC-gamma1-GFP) expressed in human epidermoid carcinoma A-431 cells. In the absence of growth factors, PLC-gamma1-GFP was present throughout the cytoplasm of A-431 cells. Treatment of the cells with epidermal growth factor (EGF) produced a very rapid redistribution of PLC-gamma1-GFP to the plasma membrane in a nonuniform manner. This translocation to the plasma membrane was insensitive to an inhibitor of phosphatidylinositol 3-kinase and was independent of cell adhesion. However, the translocation was disrupted by an agent which depolymerizes the actin cytoskeleton. At later times following the addition of EGF, PLC-gamma1-GFP appeared associated with intracellular vesicles. Stimulation of A-431 cells by Texas red-conjugated EGF for more than 10 min resulted in punctate intracellular PLC-gamma1-GFP distribution that colocalized with Texas red-conjugated EGF. This suggests that PLC-gamma1 is translocated to endosomes after EGF treatment, probably by associating with the internalized and autophosphorylated EGF receptor. Fractionation studies demonstrated that the EGF-induced plasma membrane-localized PLC-gamma1 is concentrated in caveolae microdomains. Disruption of caveolae with methyl-beta-cyclodextrin resulted in the ablation of EGF-induced, but not bradykinin-induced, mobilization of intracellular Ca(2+). This treatment, however, only partially decreased PLC-gamma1 membrane translocation.


Assuntos
Membrana Celular/metabolismo , Endossomos/metabolismo , Fator de Crescimento Epidérmico/farmacologia , Isoenzimas/metabolismo , Fosfolipases Tipo C/metabolismo , Cavéolas/enzimologia , Cavéolas/metabolismo , Proteínas de Fluorescência Verde , Humanos , Isoenzimas/genética , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Microdomínios da Membrana/enzimologia , Microdomínios da Membrana/metabolismo , Fosfolipase C gama , Transporte Proteico , Proteínas Recombinantes de Fusão/metabolismo , Células Tumorais Cultivadas , Fosfolipases Tipo C/genética
11.
J Biol Chem ; 276(12): 8627-30, 2001 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-11254653

RESUMO

To explore the functional role of phospholipase C-gamma1 (PLC-gamma1) in the induction of immediate early genes (IEGs), we have examined the influence of Plcg1 gene disruption on the expression of 14 IEG mRNAs induced by platelet-derived growth factor (PDGF). Plcg1-null embryos were used to produce immortalized fibroblasts genetically deficient in PLC-gamma1 (Null cells), and retroviral infection of those cells was used to derive PLC-gamma1 re-expressing cells (Null+ cells). In terms of PDGF activation of PDGF receptor tyrosine phosphorylation as well as the mitogen-activated protein kinases Erk1 and Erk2, Null and Null+ cells responded equivalently. However, the PDGF-dependent expression of all IEG mRNAs was diminished in cells lacking PLC-gamma1. The expression of FIC, COX-2, KC, JE, and c-fos mRNAs were most strongly compromised, as the stimulation of these genes was reduced by more than 90% in cells lacking PLC-gamma1. The combination of PMA and ionomycin, downstream analogs of PLC activation, did provoke expression of mRNAs for these IEGs in the Null cells. We conclude that PLC-gamma1 is necessary for the maximal expression of many PDGF-induced IEGs and is essential for significant induction of at least five IEGs.


Assuntos
Regulação da Expressão Gênica/fisiologia , Genes Precoces , Isoenzimas/metabolismo , Fator de Crescimento Derivado de Plaquetas/fisiologia , Transcrição Gênica/fisiologia , Fosfolipases Tipo C/metabolismo , Animais , Linhagem Celular , Camundongos , Camundongos Knockout , Fosfolipase C gama , Transdução de Sinais/fisiologia
12.
J Nat Toxins ; 9(1): 63-71, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10701182

RESUMO

To establish the safety data of shellfish in southern Taiwan, a total of 3,074 specimens of 30 shellfish species were seasonally collected from August 1995 to March 1997. These samples were assayed for the presence of tetrodotoxin (TTX) and paralytic shellfish poisons (PSP) by the bioassay methods. It was found that some major shellfish including oyster, clam, ear shell, and purple clam were nontoxic, but four species, Babylonia formosae, Niotha clathrata, Natica lineata, and Natica vitellus, were toxic. The toxic percentages of these four species was 1% in B. formosae, 56% in N. clathrata, 37% in N. lineata, and 23% in N. vitellus. The toxic composition was TTX in B. formosae. In the other three shellfish types the toxic composition was TTX and PSP.


Assuntos
Contaminação de Alimentos/estatística & dados numéricos , Toxinas Marinhas/toxicidade , Frutos do Mar , Animais , Coleta de Dados , Toxinas Marinhas/análise , Estações do Ano , Taiwan
13.
Virology ; 264(1): 187-94, 1999 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-10544144

RESUMO

In order to obtain a mutant of Sindbis virus (SV) with a low methionine-resistant (LMR) phenotype, i.e., able to replicate in methionine-deprived Aedes albopictus mosquito cells, standard SV (SV(STD)) was passaged 17 times in mosquito cells maintained in a low methionine medium and then plaque-purified, also in mosquito cells. Although the virus obtained by this procedure, SV(LM17), did have the desired LMR phenotype, it also appeared to have acquired a host-range phenotype. We have now characterized the host-range phenotype of SV(LM17) in greater detail. In yield assays, the titer of SV(LM17) produced by chick embryo fibroblasts (CEF) was 100- to 1000-fold lower than that from mosquito cells. SV(STD), in contrast, produced a similar titer of virus from the two cell types. On the other hand, when SV(LM17) was assayed directly by plaque formation on CEF and on mosquito cell monolayers, no host restriction in CEF was observed. When CEF were infected with SV(LM17), viral proteins were synthesized normally, pE2 was processed to E2, and E2 was demonstrated by the fluorescent antibody method to reach the cell surface. However, electron microscopy of SV(LM17)-infected cells revealed an absence of extracellular virions and of budding particles; also, nucleocapsids were not aligned beneath the plasma membrane. By sequence determination and by site-directed mutagenesis, it was determined that the host restriction of SV(LM17) was due to a change from Ala to Val at position 251 of the E2 protein. Substitution of Gly or Leu at this position also resulted in the same host range phenotype.


Assuntos
DNA Viral/genética , Sindbis virus/fisiologia , Transcrição Gênica , Proteínas do Envelope Viral/fisiologia , Aedes/virologia , Substituição de Aminoácidos , Animais , Embrião de Galinha , Células Clonais , Fibroblastos/citologia , Fibroblastos/virologia , Mutagênese Sítio-Dirigida , Fenótipo , Proteínas Recombinantes/metabolismo , Sindbis virus/genética , Proteínas do Envelope Viral/genética
14.
Proc Natl Acad Sci U S A ; 95(15): 8514-9, 1998 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-9671709

RESUMO

Most human adenoviruses encode two virus-associated (VA) RNAs, VA RNAI and VA RNAII, that accumulate to high levels in the cytoplasm of infected cells. The function of VA RNAI in blocking the activation of the cellular kinase PKR is well known, but the role of VA RNAII is obscure. Herein we characterize and purify several human proteins that interact preferentially with VA RNAII in Northwestern blot assays. Two of these proteins were identified as RNA helicase A and NF90, a component of the heterodimeric nuclear factor of activated T cells (NFAT). They copurified with the smaller NFAT subunit, NF45, which did not bind VA RNAII, and with an unidentified protein, p97, which did bind VA RNAII. Both RNA helicase A and NF90 contain two copies of a double-stranded (ds) RNA binding motif and bind strongly to dsRNA. NF90 interacts with RNAs in the following order of affinity: dsRNA > VA RNAII > VA RNAI > single-stranded RNA. Furthermore, VA RNAII is more effective than VA RNAI as an inhibitor of RNA helicase activity. These data identify RNA helicase A and NF90 as cellular proteins with an affinity for dsRNA and other structured RNA molecules and suggest that their functions are subject to regulation by RNA ligands including VA RNAII.


Assuntos
Adenoviridae/genética , Proteínas Nucleares , RNA Viral/genética , Proteínas de Ligação a RNA/isolamento & purificação , Sequência de Aminoácidos , Northern Blotting , Western Blotting , Linhagem Celular , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/isolamento & purificação , Proteínas de Ligação a DNA/metabolismo , Humanos , Dados de Sequência Molecular , Fatores de Transcrição NFATC , Proteína do Fator Nuclear 45 , Proteínas do Fator Nuclear 90 , RNA Helicases , RNA Nucleotidiltransferases/química , RNA Nucleotidiltransferases/isolamento & purificação , RNA Nucleotidiltransferases/metabolismo , RNA Viral/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/isolamento & purificação , Fatores de Transcrição/metabolismo
15.
Virology ; 235(2): 235-40, 1997 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-9281503

RESUMO

JKT-7400 virus is an orbivirus originally isolated from Culex mosquitoes. In earlier work we had described the viral structural proteins and presented evidence suggesting that a minor protein, VP6, located in the viral core was the viral guanylyltransferase. We now show that gradient-purified JKT-7400 virions possess a methyltransferase (MTase) activity which can use GTP or GDP as the methyl acceptor. The apparent Km of the MTase for S-adenosylmethionine (AdoMet) was 25 microM. Photoaffinity labeling experiments in which 3H-[methyl]-AdoMet was incubated with virions or viral cores demonstrated labeling of VP4, a minor protein present in the viral core, suggesting that this protein is the viral MTase. Labeling of VP4 was inhibited by addition of unlabeled AdoMet or S-adenosylhomocysteine (AdoHcy).


Assuntos
Aedes/virologia , Proteínas do Capsídeo , Capsídeo/metabolismo , Metiltransferases/metabolismo , Orbivirus/enzimologia , Marcadores de Afinidade/metabolismo , Animais , Células Cultivadas , Guanosina Trifosfato/metabolismo , Nucleotídeos/metabolismo , S-Adenosilmetionina/metabolismo , Especificidade por Substrato , Proteínas Virais/metabolismo
16.
Virology ; 228(1): 19-28, 1997 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-9024806

RESUMO

JKT-7400 virus, an orbivirus originally isolated from Culex mosquitos, was plaque purified and adapted to Aedes albopictus mosquito cells. Conditions which enhance viral cytopathic effect and optimize plaque formation are described. In contrast to bluetongue virus, the prototype orbivirus, no replication of JKT-7400 virus in vertebrate cells was observed. The core particle of JKT-7400 virus contains 10 segments of dsRNA and three minor proteins, VP1, VP4, and VP6. The inner shell contains two major proteins, VP2 and VP7, and the outer shell consists of the other two major proteins, VP3 and VP5. Evidence is presented suggesting that the viral protein associated with the capping of virus mRNA, i.e., the guanylyltransferase, is VP6, one of the core proteins.


Assuntos
Culex/virologia , Nucleotidiltransferases/metabolismo , Orbivirus/enzimologia , Proteínas Estruturais Virais/metabolismo , Aedes/citologia , Animais , Capsídeo/isolamento & purificação , Linhagem Celular , Efeito Citopatogênico Viral , Genoma Viral , Nucleotidiltransferases/química , Nucleotidiltransferases/isolamento & purificação , Orbivirus/genética , Orbivirus/crescimento & desenvolvimento , Orbivirus/isolamento & purificação , Proteínas do Core Viral/isolamento & purificação , Proteínas Estruturais Virais/química , Proteínas Estruturais Virais/isolamento & purificação , Vírion
17.
Mol Reprod Dev ; 42(2): 141-8, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8562059

RESUMO

In the preceding study (Okamura et al., 1992; Biol Reprod 47:1040-1052) we suggested that a 135-kDa protein secreted by porcine epididymis is involved in the sperm maturation. In this work, we have isolated the cDNA clone coding the 135-kDa protein in an effort to investigate its structure and function. The 135-kDa protein was purified from porcine cauda epididymal fluid. Three oligonucleotide probes were synthesized according to the amino acid sequences of N-termini of the native protein and trypsin-digested peptides. A cDNA clone hybridizing with these three probes was isolated from the cDNA library derived from the porcine proximal corpus epididymis. It encodes a novel protein with 1,006 amino acid residues in an open reading frame. Its overall amino acid sequence was significantly homologous (25.7%) to the alpha-mannosidase precursor of Dictiostelium discoideum (P34098). The 135-kDa protein could digest both p-nitro-phenyl-alpha-D-mannoside and high mannose oligo saccharide (Man8-GlcNAc2), strongly suggesting that it is an alpha-mannosidase homologue. The expression of this protein was specific to porcine and was localized to the very narrow parts of epididymis: the border of the caput and corpus epididymis. This protein may serve as a good marker for the functional differentiation in porcine epididymis. A possible role of this protein in the species-specific sperm-egg interaction is discussed.


Assuntos
DNA Complementar/genética , Epididimo/enzimologia , Manosidases/genética , Manosidases/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Sequência de Carboidratos , Membrana Celular/enzimologia , Clonagem Molecular , Dictyostelium/enzimologia , Dictyostelium/genética , Epididimo/citologia , Feminino , Masculino , Manosidases/fisiologia , Dados de Sequência Molecular , Oligossacarídeos/química , Homologia de Sequência de Aminoácidos , Maturação do Esperma/fisiologia , Interações Espermatozoide-Óvulo/fisiologia , Espermatozoides/enzimologia , Especificidade por Substrato , Suínos , Distribuição Tecidual , alfa-Manosidase
18.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 15(4): 202-4, 1995 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-7647539

RESUMO

Our previous study had demonstrated that Chinese medicine Epimedium Sagittatum (ES) exerted immuno-enhancing effect on the animal model of chronic renal insufficiency. In present study, we investigated the therapeutic effect of ES on patients of hemodialysis maintenance. 22 cases of regular hemodialytic patients were treated with ES in the form of decoction. 12 patients with hemodialysis were served as controls. It was found that ES had sexual potentiation effect and improved the quality of life in the patients of chronic renal failure with regular hemodialysis. Interleukin 2 (IL-2) activity of peripheral blood monocytes (PBMC) stimulated by PHA was increased significantly in the patients treated with ES. It was suggested that Chinese medicine ES had therapeutic effect on sexual disorder and immunologic inadequacy in the patients of chronic renal failure undergoing hemodialysis.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Medicamentos de Ervas Chinesas/uso terapêutico , Falência Renal Crônica/terapia , Qualidade de Vida , Diálise Renal , Adulto , Feminino , Humanos , Imunidade Celular , Interleucina-2/biossíntese , Falência Renal Crônica/imunologia , Masculino , Pessoa de Meia-Idade
19.
Zhonghua Yi Xue Za Zhi ; 74(10): 629-31, 648, 1994 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-7842344

RESUMO

A multiparametric analysis was made to demonstrate that brief period of ischemia can initiate extensive loss in a rat kidney through the process of apoptosis during early reperfusion. Microscopic examination of mouse renal tissues subject to a 5, 30, or 45 minute period of complete ischemia showed the presence of apoptotic bodies both within and occasionally between renal tubular, appearing as early 6 hours after reperfusion and increasing in numbers at 12 hours. Furthermore, DNA extracted from such reperfusion renal tissue demonstrated the appearance of a distinct "ladder pattern" of DNA fragments after electrophoresis in agarose gels. It was suggested that renal reperfusion injury after ischemia can initiate a form of cell death-apoptosis that is drastically different from cellular necrosis induced by prolonged severe ischemia.


Assuntos
Apoptose , Isquemia/patologia , Rim/irrigação sanguínea , Traumatismo por Reperfusão/patologia , Animais , DNA/análise , Eletroforese , Camundongos
20.
Antiviral Res ; 22(4): 285-94, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8279817

RESUMO

Earlier work in our laboratory has shown that the replication of Sindbis virus in Aedes albopictus mosquito cells is inhibited by ribavirin (Rbv) and mycophenolic acid (MPA) (Sarver and Stollar (1978) Virology 91, 267-282; Malinoski and Stollar (1980) Virology 102, 473-476). We report here that the antiviral effect of Rbv and MPA can be reversed by depriving infected cells of methionine or isoleucine, or by treating them with fluorodeoxyuridine (FUdR) or cycloleucine. We suggest that, as was the case when the antiviral activity of Rbv was reversed by actinomycin D (Malinoski and Stollar (1981a) Virology 110, 281-291), these effects may be mediated by changes in the GTP pools of treated cells.


Assuntos
Antivirais/antagonistas & inibidores , Ribavirina/antagonistas & inibidores , Sindbis virus/efeitos dos fármacos , Aedes , Animais , Antivirais/farmacologia , Divisão Celular , Células Cultivadas , Floxuridina/farmacologia , Isoleucina/farmacologia , Metionina/farmacologia , Ácido Micofenólico/farmacologia , Ribavirina/farmacologia
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