Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 173
Filtrar
2.
Virology ; 566: 60-68, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34871905

RESUMO

The emergence of SARS-CoV-2 virus has resulted in a worldwide pandemic, but effective antiviral therapies are not widely available. To improve treatment options, we conducted a high-throughput screen to uncover compounds that block SARS-CoV-2 infection. A minimally pathogenic human betacoronavirus (OC43) was used to infect physiologically-relevant human pulmonary fibroblasts (MRC5) to facilitate rapid antiviral discovery in a preclinical model. Comprehensive profiling was conducted on more than 600 compounds, with each compound arrayed across 10 dose points. Our screening revealed several FDA-approved agents that can attenuate both OC43 and SARS-CoV-2 viral replication, including lapatinib, doramapimod, and 17-AAG. Importantly, lapatinib inhibited SARS-CoV-2 RNA replication by over 50,000-fold. Further, both lapatinib and doramapimod could be combined with remdesivir to improve antiviral activity in cells. These findings reveal novel therapeutic avenues that could limit SARS-CoV-2 infection.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Antivirais/farmacologia , Tratamento Farmacológico da COVID-19 , Lapatinib/farmacologia , SARS-CoV-2/efeitos dos fármacos , Monofosfato de Adenosina/farmacologia , Alanina/farmacologia , Animais , Benzoquinonas/farmacologia , COVID-19/virologia , Linhagem Celular , Chlorocebus aethiops , Combinação de Medicamentos , Descoberta de Drogas , Sinergismo Farmacológico , Ensaios de Triagem em Larga Escala , Humanos , Lactamas Macrocíclicas/farmacologia , Naftalenos/farmacologia , Compostos de Fenilureia/farmacologia , Pirazóis/farmacologia , RNA Viral/metabolismo , Células Vero , Replicação Viral/efeitos dos fármacos
3.
Rev Sci Instrum ; 91(11): 113302, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33261450

RESUMO

We report the characteristics of extracted beam current in the test plasma produced by direct current for sheet plasma upgrade producing negative ions by volume production without cesium (Cs) seeding. The negative hydrogen ion beam is extracted by a two-grid extraction system, which is located at the periphery of the sheet plasma. Experimental observations show that (i) negative hydrogen ions are successfully extracted from the sheet plasma by single/multi-aperture grids and (ii) the ratio of the extracted electron current IEG(e) and the hydrogen negative ion current IEG(H-), IEG(e)/Ic(H-), decreases from 8.0 to 2.0 with an increase in the height of the electron fence (HEF), which is a filter that prevents electron diffusion from the extraction region.

5.
Benef Microbes ; 9(3): 357-365, 2018 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-29482338

RESUMO

Ingestion of Bacillus subtilis C-3102 spores (C-3102) has relieved the symptoms of diarrhoea in piglets and changed the composition of gut microbiota in humans. Recently, it was suggested that the composition of the human gut microbiota affects stool consistency. In this study, a double-blind, randomised, placebo-controlled trial was conducted to assess the preventive effects of chronic diarrhoea in healthy volunteers with loose stools by ingestion of C-3102. The results showed that oral doses of C-3102 tablets significantly decreased the Bristol Stool Scale score and stool frequency, and also significantly improved abdominal sounds. With regard to gut microbiota, the relative abundance of Lachnospira, Actinomyces and SMB53 were significantly changed. This study shows that C-3102 could be effective for treating loose stools (Trial registration: UMIN000022583, http://tinyurl.com/ya4refqn ).


Assuntos
Antidiarreicos/administração & dosagem , Bacillus subtilis/crescimento & desenvolvimento , Voluntários Saudáveis , Probióticos/administração & dosagem , Administração Oral , Método Duplo-Cego , Microbioma Gastrointestinal , Humanos , Placebos/administração & dosagem , Comprimidos/administração & dosagem
6.
Int J Obes (Lond) ; 38(11): 1432-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24566854

RESUMO

BACKGROUND: Chronic inflammation in adipose tissue together with obesity induces insulin resistance. Inhibitors of chronic inflammation in adipose tissue can be a potent candidate for the treatment of diabetes; however, only a few compounds have been discovered so far. The objective of this study was to find a novel inhibitor that can suppress the inflammatory response in adipose tissue and to elucidate the intracellular signaling mechanisms of the compound. METHODS: To find the active compounds, we established an assay system to evaluate the inhibition of induced MCP-1 production in adipocyte/macrophage coculture in a plant extract library. The active compound was isolated by performing high-performance liquid chromatography (HPLC) and was determined as 4ß-hydroxywithanolide E (4ßHWE) by nuclear magnetic resonance (NMR) and mass spectroscopy (MS) spectral analyses. The effect of 4ßHWE on inflammation in adipose tissue was assessed with adipocyte culture and db/db mice. RESULTS: During the screening process, Physalis pruinosa calyx extract was found to inhibit production of MCP-1 in coculture strongly. 4ßHWE belongs to the withanolide family of compounds, and it has the strongest MCP-1 production inhibitory effect and lowest toxicity than any other withanolides in coculture. Its anti-inflammatory effect was partially dependent on the attenuation of NF-κB signaling in adipocyte. Moreover, in vivo experiments showed that the oral administration of 4ßHWE to db/db mice resulted in the inhibition of macrophage invasion and cytokine expression in adipose tissue after 2 weeks of treatment; improved the plasma adiponectin, non-esterified fatty acids and MCP-1 concentrations; and increased glucose tolerance after 3 to 4 weeks of treatment. CONCLUSIONS: These results suggest that 4ßHWE has anti-inflammatory effect via inhibition of NF-κB activation in adipocyte. Moreover, the attenuation of inflammation in adipocyte has an effect on the inhibition of macrophage accumulation in obese adipose tissue. Consequently, 4ßHWE improves impaired glucose tolerance. Thus, 4ßHWE is a useful natural anti-inflammatory compound to attenuate progression of diabetes and obesity.


Assuntos
Adipócitos/efeitos dos fármacos , Tecido Adiposo/patologia , Quimiocina CCL2/antagonistas & inibidores , Inflamação/tratamento farmacológico , Macrófagos/efeitos dos fármacos , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Physalis/química , Extratos Vegetais/farmacologia , Transdução de Sinais/efeitos dos fármacos , Vitanolídeos/farmacologia , Células 3T3-L1 , Adipócitos/metabolismo , Adipócitos/patologia , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Animais , Quimiocina CCL2/biossíntese , Cromatografia Líquida de Alta Pressão , Técnicas de Cocultura , Glucose/metabolismo , Immunoblotting , Resistência à Insulina , Macrófagos/metabolismo , Masculino , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos NOD/metabolismo , Ressonância Magnética Nuclear Biomolecular , Fitoterapia , Vitanolídeos/isolamento & purificação
8.
Eur J Clin Microbiol Infect Dis ; 29(5): 519-25, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20179982

RESUMO

The aim of this study is to confirm the usefulness of sputum sampling from the hypopharynx through the nose to identify causative bacteria of pediatric community-acquired lower respiratory tract infection (CA-LRTI) and compare its features between the patients with and without underlying diseases. A retrospective study was performed on 244 pediatric patients hospitalized for CA-LRTI of suspected bacterial etiology. Sputum sample was obtained from these patients by aspirating airway secretion through the nose or the tracheostomy orifice, or coughing up by themselves. Sputum samples were assessed as suitable in 119 (74.4%) of 160 patients with CA-LRTI of suspected pure bacterial etiology. Ninety-six (70.1%) of 137 samples suctioned from the hypopharynx through the nose were suitable for bacterial examination. Seventy-eight (73.6%) of 106 patients identified with causative bacteria had some underlying diseases, and the other 28 patients did not have any underlying diseases. Proportions and antibiotics susceptibility profiles of the identified causative bacteria were almost similar in the patients with and without underlying diseases. Sputum sampling from the hypopharynx through the nose might be significant in pediatric CA-LRTI of suspected bacterial etiology. The initial treatment for patients without underlying diseases would be applicable to those with underlying diseases in the CA-LRTI of children.


Assuntos
Bactérias/isolamento & purificação , Infecções Bacterianas/microbiologia , Infecções Comunitárias Adquiridas/microbiologia , Infecções Respiratórias/microbiologia , Escarro/microbiologia , Adolescente , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Infecções Bacterianas/complicações , Infecções Bacterianas/epidemiologia , Criança , Pré-Escolar , Estudos de Coortes , Infecções Comunitárias Adquiridas/complicações , Feminino , Haemophilus influenzae/efeitos dos fármacos , Haemophilus influenzae/isolamento & purificação , Hospitais , Humanos , Lactente , Masculino , Testes de Sensibilidade Microbiana , Infecções Respiratórias/complicações , Estudos Retrospectivos , Estatísticas não Paramétricas , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pneumoniae/isolamento & purificação
9.
J Phys Condens Matter ; 20(46): 465221, 2008 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-21693859

RESUMO

Low-frequency spin fluctuation dynamics in paramagnetic spinel LiV(2)O(4), a rare 3d-electron heavy-fermion system, is investigated. A parametrized self-consistent renormalization (SCR) theory of the dominant AFM spin fluctuations is developed and applied to describe temperature and pressure dependences of the low-T nuclear spin-lattice relaxation rate 1/T(1) in this material. The experimental data for 1/T(1) available down to ∼1 K are well reproduced by the SCR theory, showing the development of AFM spin fluctuations as the paramagnetic metal approaches a magnetic instability under the applied pressure. The low-T upturn of 1/T(1)T detected below 0.6 K under the highest applied pressure of 4.74 GPa is explained as the nuclear spin relaxation effect due to the spin freezing of magnetic defects unavoidably present in the measured sample of LiV(2)O(4).

10.
Br Poult Sci ; 48(1): 90-7, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17364546

RESUMO

1. Effects of dietary supplementation of astaxanthin (Ax) provided from Phaffia rhodozyma on lipid peroxidation, hepatic drug metabolism, antibody titres to sheep red blood cells (SRBC) and splenocyte proliferation to mitogens were determined in male broiler chicks. 2. Chicks, one week old, were given diets with or without oxidised fat (0 or 3.7 meq of peroxide value (POV)/kg diet) and/or Ax (0 or 100 mg/kg diet) for 14 d, ad libitum. 3. Lipid peroxidation, estimated by 2-thiobarbituric acid reactants values in liver, spleen, heart, plasma and hepatic microsomes, were increased by feeding a diet containing oxidised fat (P<0.05) but were not affected by Ax feeding. 4. Cytochrome P-450 contents in hepatic microsome tended to be increased by feeding Ax. 5. Anti-SRBC titre was not affected by oxidised fat or Ax feeding, while plasma immunogloblin (Ig) G concentration was increased by Ax feeding but was not affected by oxidised fat feeding. 6. When chicks were fed on the diet without oxidised fat, Ax enhanced splenocyte proliferation stimulated by both concanavalin A and pokeweed mitogen, while in chicks fed on a diet containing oxidised fat, Ax reduced the proliferation (P<0.01 for Ax and oxidised fat interaction). 7. The results indicated that dietary supplementation of Ax from Phaffia rhodozyma had an impact on T cell proliferation and Ig G production as a part of acquired immunity, but was not effective in preventing lipid peroxidation in male broiler chicks.


Assuntos
Galinhas/metabolismo , Gorduras na Dieta/administração & dosagem , Suplementos Nutricionais , Fígado/metabolismo , Animais , Galinhas/imunologia , Sistema Enzimático do Citocromo P-450/metabolismo , Citocromos b5/metabolismo , Gorduras na Dieta/metabolismo , Imunoglobulina G/sangue , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/enzimologia , Masculino , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Xantofilas/administração & dosagem , Xantofilas/metabolismo
11.
Int J Gynecol Cancer ; 14(2): 388-94, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15086745

RESUMO

Undifferentiated endometrial carcinoma of the uterus is rare, and is thought to show a poor prognosis. To date, there is no consensus as to the optimal chemotherapy for this carcinoma. We report a rare case of this carcinoma in a patient who was treated surgically in combination with chemotherapy using a regimen designed by us. This chemotherapy consists of tetrahydropyranyl-adriamycin, paclitaxel, and carboplatin. This regimen is called TTJ [tetrahydropryanyl-adriamycin, taxan (paclitaxel), JM-8 (carboplatin)] chemotherapy and showed a marked effect. The patient was a 52-year-old woman with a giant tumor of the uterus measuring 28 x 18 x 13 cm and weighing 3386 g. She underwent total abdominal hysterectomy with bilateral salpingo-oophorectomy and omentectomy, but residual carcinoma remained on the surface of the small intestine. Pathologically tumor tissues comprised the whole uterus except for the uterine cervix and there were tumor tissues in the omentum. She was treated with six courses of TTJ chemotherapy without major side-effects. Currently, she remains alive without metastasis 41 months after hysterectomy. This report describes a rare case of undifferentiated endometrial carcinoma of the uterus and introduces TTJ chemotherapy resulting in the remarkable effect on this carcinoma.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Endometrioide/diagnóstico , Carcinoma Endometrioide/tratamento farmacológico , Neoplasias Uterinas/diagnóstico , Neoplasias Uterinas/tratamento farmacológico , Carboplatina/administração & dosagem , Carcinoma Endometrioide/sangue , Carcinoma Endometrioide/patologia , Carcinoma Endometrioide/cirurgia , Terapia Combinada , Diagnóstico Diferencial , Doxorrubicina/administração & dosagem , Feminino , Humanos , Histerectomia , L-Lactato Desidrogenase/sangue , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Neoplasia Residual , Ovariectomia , Paclitaxel/administração & dosagem , Neoplasias Uterinas/sangue , Neoplasias Uterinas/patologia , Neoplasias Uterinas/cirurgia
12.
Br Poult Sci ; 45(1): 133-8, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15115211

RESUMO

1. The experiments were conducted to evaluate astaxanthin (Ax) uptake in several tissues and plasma lipoproteins of male broiler chickens fed on Phaffia rhodozyma containing a high concentration of Ax. 2. Male broiler chicks (5 weeks of age) fasted for 16h were given 0 or 45 mg Ax as Phaffia rhodozyma through the crop and blood was collected over the following 24 h. Ax appeared in the plasma at 2 h after administration into the crop. Most (more than 70%) of the Ax was contained in the high density lipoprotein (HDL) fraction in the plasma irrespective of blood sampling times and administration procedure of Ax. 3. Male broiler chicks (2 weeks of age) were fed on a diet containing 0, 50 or 100 mg/kg of yeast Ax for 2 weeks. Of the tissues examined, Ax concentration in the small intestine was highest, followed by subcutaneous fat, abdominal fat, spleen, liver, heart, kidney and skin. The lowest concentration was in the muscles. Ax concentration in the small intestine, subcutaneous fat, abdominal fat, liver and skin rose as dietary content increased, but this was not the case for the spleen, heart, kidney and muscles except for M. pecloralis superficialis. 4. Over 50% of Ax deposited in liver tissues was detected in the microsomal fraction and 15% was in the mitochondrial fraction. In muscles, both fractions of mitochondria and sarcoplasmic reticulum contained Ax.


Assuntos
Basidiomycota , Galinhas/metabolismo , Lipoproteínas/sangue , beta Caroteno/análogos & derivados , beta Caroteno/farmacocinética , Animais , Galinhas/sangue , Fígado/metabolismo , Masculino , Microssomos Hepáticos/metabolismo , Mitocôndrias Hepáticas/metabolismo , Músculos Peitorais/metabolismo , Distribuição Tecidual , Xantofilas , beta Caroteno/administração & dosagem , beta Caroteno/sangue
13.
Eur J Cancer ; 40(5): 725-33, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15010074

RESUMO

A central pathology review system with an immunophenotyping laboratory was established in Japan to support the clinical trial, the Japan Association of Childhood Leukaemia Study (JACLS) NHL-98, for patients with paediatric non-Hodgkin's lymphoma (NHL). Pathology samples from 155 clinically-suspected NHL cases were evaluated centrally initially using the Revised European-American Lymphoma (REAL) classification in a rapid review (within 2 weeks after surgery/biopsy) and then later at the consensus review (once a year). The samples were subsequently re-classified according to the new World Health Organisation (WHO) classification. After the pathology review, 96 (62%) patients were eligible for the study, and 58 of them (60%) had extra-nodal primaries. These NHL cases included B-cell lymphomas (precursor B-cell, 11; Burkitt, 18; diffuse large B-cell, 18; not otherwise specified, 3) and T/Natural Killer (NK)-cell lymphomas (precursor T-cell, 23; anaplastic large cell, 20; others, 3). There was excellent concordance in making the diagnoses (95/96, 99%) and typing (93/96, 97%) of NHL between the rapid and consensus reviews. Five cases, initially diagnosed as diffuse large B-cell lymphoma by the review, were re-classified as Burkitt lymphoma according to the immunocytochemical criteria by the WHO classification. A total of 59 (38%) cases were excluded from the study: they were Hodgkin lymphoma (7), leukaemias (11), reactive lymphoid hyperplasia (20), necrotizing lymphadenitis (7), no consensus diagnosis (1), insufficient materials (2), and others (11). This is the first report of the central pathology review from the paediatric NHL group study in Japan. Because various diseases, either neoplastic or reactive, mimicked NHL, clinically and histopathologically, the central pathology review system was critical and essential for patient enrollment and protocol assignment in our clinical trial. Through the two-step review system, highly reliable data were generated to support this study.


Assuntos
Linfoma não Hodgkin/patologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Imunofenotipagem , Lactente , Recém-Nascido , Japão , Linfoma não Hodgkin/classificação , Masculino
15.
J Virol ; 75(23): 11384-91, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11689619

RESUMO

Paramyxoviruses are assembled at the surface of infected cells, where virions are formed by the process of budding. We investigated the roles of three Sendai virus (SV) membrane proteins in the production of virus-like particles. Expression of matrix (M) proteins from cDNA induced the budding and release of virus-like particles that contained M, as was previously observed with human parainfluenza virus type 1 (hPIV1). Expression of SV fusion (F) glycoprotein from cDNA caused the release of virus-like particles bearing surface F, although their release was less efficient than that of particles bearing M protein. Cells that expressed only hemagglutinin-neuraminidase (HN) released no HN-containing vesicles. Coexpression of M and F proteins enhanced the release of F protein by a factor greater than 4. The virus-like particles containing F and M were found in different density gradient fractions of the media of cells that coexpressed M and F, a finding that suggests that the two proteins formed separate vesicles and did not interact directly. Vesicles released by M or F proteins also contained cellular actin; therefore, actin may be involved in the budding process induced by viral M or F proteins. Deletion of C-terminal residues of M protein, which has a sequence similar to that of an actin-binding domain, significantly reduced release of the particles into medium. Site-directed mutagenesis of the cytoplasmic tail of F revealed two regions that affect the efficiency of budding: one domain comprising five consecutive amino acids conserved in SV and hPIV1 and one domain that is similar to the actin-binding domain required for budding induced by M protein. Our results indicate that both M and F proteins are able to drive the budding of SV and propose the possible role of actin in the budding process.


Assuntos
Vírus Sendai/fisiologia , Proteínas Virais de Fusão/fisiologia , Proteínas da Matriz Viral/fisiologia , Actinas/fisiologia , Sequência de Aminoácidos , Linhagem Celular , Meios de Cultura , Citoplasma/virologia , Humanos , Microscopia Eletrônica , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos , Proteínas Virais de Fusão/química
16.
Int J Hematol ; 74(1): 95-100, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11530814

RESUMO

We present a case of adenovirus (ADV) infection in a patient who had undergone nonmyeloablative stem cell transplantation (NST). A 50-year-old man with chronic myelogenous leukemia in the second chronic phase underwent NST from an HLA 2-loci-mismatched sibling. ADV hemorrhagic cystitis developed and progressed to lethal pneumonia. ADV was isolated from urine, bronchoalveolar lavage fluid, and postmortem specimens of kidney and liver. Because there are few reports of lethal pneumonia associated with ADV in Japan, we present the case and discuss the cause of and therapy for the infection.


Assuntos
Infecções por Adenoviridae/etiologia , Transplante de Células-Tronco Hematopoéticas , Pneumonia Viral/etiologia , Vidarabina/análogos & derivados , Adenovírus Humanos/isolamento & purificação , Soro Antilinfocitário , Líquido da Lavagem Broncoalveolar/virologia , Bussulfano , Cistite/complicações , Cistite/virologia , Evolução Fatal , Humanos , Hospedeiro Imunocomprometido , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico , Leucemia Mieloide de Fase Crônica/complicações , Leucemia Mieloide de Fase Crônica/terapia , Contagem de Linfócitos , Subpopulações de Linfócitos , Masculino , Metilprednisolona/efeitos adversos , Metilprednisolona/uso terapêutico , Pessoa de Meia-Idade , Pneumonia Viral/virologia , Linfócitos T , Tacrolimo/efeitos adversos , Tacrolimo/uso terapêutico , Condicionamento Pré-Transplante , Transplante Homólogo
17.
Eur J Biochem ; 268(18): 4928-39, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11559362

RESUMO

Sciadonic acid (20:3 Delta-5,11,14) is an n-6 series trienoic acid that lacks the Delta8 double bond of arachidonic acid. This fatty acid is not converted to arachidonic acid in higher animals. In this study, we characterized the metabolic behavior of sciadonic acid in the process of acylation to phospholipid of HepG2 cells. One of the characteristics of fatty acid compositions of phospholipids in sciadonic acid-supplemented cells is a higher proportion of sciadonic acid in phosphatidylinositol (PtdIns) (27.4%) than in phosphatidylethanolamine (PtdEtn) (23.2%), phosphatidylcholine (PtdCho) (17.3%) and phosphatidylserine (PtdSer) (20.1%). Similarly, the proportion of arachidonic acid was higher in PtdIns (35.8%) than in PtdEtn (29.1%), PtdSer (18.2%) and PtdCho (20.2%) in arachidonic-acid-supplemented cells. The extensive accumulation of sciadonic acid in PtdIns resulted in the enrichment of newly formed 1-stearoyl-2-sciadonoyl molecular species (38%) in PtdIns and caused the reduction in the level of pre-existing arachidonic-acid-containing molecular species. The kinetics of incorporation of sciadonic acid to PtdEtn, PtdSer and PtdIns of cells were similar to those of arachidonic acid. In contrast to sciadonic acid, neither eicosapentaenoic acid (20:5 Delta-5,8,11,14,17) nor juniperonic acid (20:4 Delta-5,11,14,17) accumulated in the PtdIns fraction. Rather, these n-3 series polyunsaturated fatty acids, once incorporated into PtdIns, tended to be excluded from PtdIns. In addition, the level of arachidonic-acid-containing PtdIns molecular species remained unchanged by eicosapentaenoic-acid-supplementation. These results suggest that sciadonic acid or sciadonic-acid-containing glycerides are metabolized in a similar manner to arachidonic acid or arachidonic-acid-containing glyceride in the biosynthesis of PtdIns and that sciadonic acid can effectively modify the molecular species composition of PtdIns in HepG2 cells. In this regard, sciadonic acid will be an interesting experimental tool to clarify the significance of arachidonic acid-residue of PtdIns-origin bioactive lipids.


Assuntos
Ácido Araquidônico/metabolismo , Ácidos Araquidônicos/metabolismo , Fosfatidilinositóis/química , Fosfatidilinositóis/metabolismo , Aciltransferases/metabolismo , Animais , Ácidos Araquidônicos/química , Cromatografia Líquida de Alta Pressão , Ácido Eicosapentaenoico/química , Ácido Eicosapentaenoico/metabolismo , Ácidos Graxos Dessaturases/metabolismo , Ácidos Graxos Insaturados/química , Ácidos Graxos Insaturados/metabolismo , Humanos , Hidrogenação , Cinética , Lisofosfolipídeos/química , Lisofosfolipídeos/metabolismo , Microssomos Hepáticos/química , Microssomos Hepáticos/metabolismo , Ratos , Especificidade por Substrato , Células Tumorais Cultivadas
18.
Virology ; 283(2): 306-14, 2001 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-11336555

RESUMO

The paramyxovirus P protein is an essential component of the viral RNA polymerase composed of P and L proteins. In this study, we characterized the physical and functional interactions between P and L proteins using human parainfluenza virus type 1 (hPIV1) and its counterpart Sendai virus (SV). The hPIV1 P and SV L proteins or the SV P and hPIV1 L proteins formed complexes detected by anti-P antibodies. Functional analysis using the minigenome SV RNA containing CAT gene indicated that the hPIV1 P--SV L complex, but not the SV P--hPIV1 L complex, was biologically active. Mutant SV P or hPIV1 P cDNAs, which do not express C proteins, showed the same phenotype with wild-type P cDNAs, indicating that C proteins are not responsible for the dysfunction of SV P--hPIV1 L polymerase complex. Using the chimeric hPIV1/SV P cDNAs, we identified two regions (residues 387--423 and 511--568) on P protein, which are required for the functional interaction with hPIV1 L. These regions overlap with a previously identified domain for oligomer formation and binding to nucleocapsids. Our results indicate that in addition to a P--L binding domain, hPIV1 L requires a specific region on P protein to be biologically functional as a polymerase.


Assuntos
RNA Polimerases Dirigidas por DNA/metabolismo , Fosfoproteínas/química , Fosfoproteínas/metabolismo , Proteínas Virais/química , Proteínas Virais/metabolismo , Sequência de Aminoácidos , Células HeLa , Humanos , Dados de Sequência Molecular , Nucleocapsídeo/metabolismo , Vírus da Parainfluenza 1 Humana/metabolismo , Fosfoproteínas/genética , Respirovirus/metabolismo , Transfecção , Proteínas Virais/genética
19.
J Virol ; 75(10): 4604-13, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11312330

RESUMO

Through their hemagglutinin-neuraminidase glycoprotein, parainfluenza viruses bind to sialic acid-containing glycoconjugates to initiate infection. Although the virus-receptor interaction is a key factor of infection, the exact nature of the receptors that human parainfluenza viruses recognize has not been determined. We evaluated the abilities of human parainfluenza virus types 1 (hPIV-1) and 3 (hPIV-3) to bind to different types of gangliosides. Both hPIV-1 and hPIV-3 preferentially bound to neolacto-series gangliosides containing a terminal N-acetylneuraminic acid (NeuAc) linked to N-acetyllactosamine (Galbeta1-4GlcNAc) by the alpha2-3 linkage (NeuAcalpha2-3Galbeta1-4GlcNAc). Unlike hPIV-1, hPIV-3 bound to gangliosides with a terminal NeuAc linked to Galbeta1-4GlcNAc through an alpha2-6 linkage (NeuAcalpha2-6Galbeta1-4GlcNAc) or to gangliosides with a different sialic acid, N-glycolylneuraminic acid (NeuGc), linked to Galbeta1-4GlcNAc (NeuGcalpha2-3Galbeta1-4GlcNAc). These results indicate that the molecular species of glycoconjugate that hPIV-1 recognizes are more limited than those recognized by hPIV-3. Further analysis using purified gangliosides revealed that the oligosaccharide core structure is also an important element for binding. Gangliosides that contain branched N-acetyllactosaminoglycans in their core structure showed higher avidity than those without them. Agglutination of human, cow, and guinea pig erythrocytes but not equine erythrocytes by hPIV-1 and hPIV-3 correlated well with the presence or the absence of sialic acid-linked branched N-acetyllactosaminoglycans on the cell surface. Finally, NeuAcalpha2-3I, which bound to both viruses, inhibited virus infection of Lewis lung carcinoma-monkey kidney cells in a dose-dependent manner. We conclude that hPIV-1 and hPIV-3 preferentially recognize oligosaccharides containing branched N-acetyllactosaminoglycans with terminal NeuAcalpha2-3Gal as receptors and that hPIV-3 also recognizes NeuAcalpha2-6Gal- or NeuGcalpha2-3Gal-containing receptors. These findings provide important information that can be used to develop inhibitors that prevent human parainfluenza virus infection.


Assuntos
Gangliosídeos/metabolismo , Vírus da Parainfluenza 1 Humana/metabolismo , Vírus da Parainfluenza 3 Humana/metabolismo , Receptores Virais/metabolismo , Animais , Sequência de Carboidratos , Galactose/metabolismo , Humanos , Macaca mulatta , Dados de Sequência Molecular , Ácido N-Acetilneuramínico/metabolismo , Células Tumorais Cultivadas
20.
J Virol ; 75(3): 1117-23, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11152484

RESUMO

The paramyxovirus nucleoproteins (NPs) encapsidate the genomic RNA into nucleocapsids, which are then incorporated into virus particles. We determined the protein-protein interaction between NP molecules and the molecular mechanism required for incorporating nucleocapsids into virions in two closely related viruses, human parainfluenza virus type 1 (hPIV1) and Sendai virus (SV). Expression of NP from cDNA resulted in in vivo nucleocapsid formation. Electron micrographs showed no significant difference in the morphological appearance of viral nucleocapsids obtained from lysates of transfected cells expressing SV or hPIVI NP cDNA. Coexpression of NP cDNAs from both viruses resulted in the formation of nucleocapsid composed of a mixture of NP molecules; thus, the NPs of both viruses contained regions that allowed the formation of mixed nucleocapsid. Mixed nucleocapsids were also detected in cells infected with SV and transfected with hPIV1 NP cDNA. However, when NP of SV was donated by infected virus and hPIV1 NP was from transfected cDNA, nucleocapsids composed of NPs solely from SV or solely from hPIVI were also detected. Although almost equal amounts of NP of the two viruses were found in the cytoplasm of cells infected with SV and transfected with hPIV1 NP cDNA, 90% of the NPs in the nucleocapsids of the progeny SV virions were from SV. Thus, nucleocapsids containing heterologous hPIV1 NPs were excluded during the assembly of progeny SV virions. Coexpression of hPIV1 NP and hPIV1 matrix protein (M) in SV-infected cells increased the uptake of nucleocapsids containing hPIV1 NP; thus, M appears to be responsible for the specific incorporation of the nucleocapsid into virions. Using SV-hPIV1 chimera NP cDNAs, we found that the C-terminal domain of the NP protein (amino acids 420 to 466) is responsible for the interaction with M.


Assuntos
Nucleocapsídeo/fisiologia , Vírus da Parainfluenza 1 Humana/fisiologia , Respirovirus/fisiologia , Proteínas da Matriz Viral/fisiologia , Montagem de Vírus , Animais , Embrião de Galinha , Transfecção , Vírion/fisiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...