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1.
Breast Cancer Res Treat ; 113(3): 529-35, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18327706

RESUMEN

OBJECTIVES: This is a single center, randomized, double-blind placebo-controlled study to evaluate the NK(1)-receptor antagonist, aprepitant, in Chinese breast cancer patients. The primary objective was to compare the efficacy of aprepitant-based antiemetic regimen and standard antiemetic regimen for the prevention of chemotherapy-induced nausea and vomiting (CINV) in patients who received moderately emetogenic chemotherapy. The secondary objective was to compare the patient-reported quality of life in these two groups of patients. PATIENTS AND METHODS: Eligible breast cancer patients were chemotherapy-naive and treated with adjuvant AC chemotherapy (i.e. doxorubicin 60 mg/m(2) and cyclophosphamide 600 mg/m(2)). Patients were randomly assigned to either an aprepitant-based regimen (day 1, aprepitant 125 mg, ondansetron 8 mg, and dexamethasone 12 mg before chemotherapy and ondansetron 8 mg 8 h later; days 2 through 3, aprepitant 80 qd) or a control arm which consisted of standard regimen (day 1, ondansetron 8 mg and dexamethasone 20 mg before chemotherapy and ondansetron 8 mg 8 h later; days 2 through 3, ondansetron 8 mg bid). Data on nausea, vomiting, and use of rescue medication were collected with a self-report diary, patients quality of life were assessed by self-administered Functional Living Index-Emesis (FLIE). RESULTS: Of 127 patients randomized, 124 were assessable. For CINV in Cycle 1 AC, there was no significant difference in the proportion of patients with reported complete response, complete protection, total control, 'no vomiting', 'no significant nausea' and 'no nausea'. The requirement of rescue medication appears to be lesser in patients treated with the aprepitant-based regimen compared to those with the standard regimen (11% vs. 20%; P = 0.06). Assessment of FLIE revealed that while there was no difference in the nausea domain and the total score between the two groups; however, patients receiving standard antiemetic regimen had significantly worse quality of life in the vomiting domain (mean score [SD] = 23.99 [30.79]) when compared with those who received the aprepitant-based regimen (mean score [SD] = 3.40 [13.18]) (P = 0.0002). Both treatments were generally well tolerated. Patients treated with the aprepitant-based regimen had a significantly lower incidence of neutropenia (53.2% vs. 35.5%, P = 0.0468), grade >or= 3 neutropenia (21.0% vs. 45.2, P = 0.0042) and delay in subsequent cycle of chemotherapy (8.1% vs. 27.4%, P = 0.0048). CONCLUSION: The aprepitant regimen appears to reduce the requirement of rescue medication when compared with the control regimen for prevention of CINV in patients receiving both an anthracycline and cyclophosphamide, and is associated with a better quality of life during adjuvant AC chemotherapy.


Asunto(s)
Antieméticos/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , Morfolinas/administración & dosificación , Náusea/tratamiento farmacológico , Ondansetrón/administración & dosificación , Vómitos/tratamiento farmacológico , Adulto , Anciano , Antineoplásicos/efectos adversos , Aprepitant , Carcinoma Ductal de Mama/tratamiento farmacológico , China , Dexametasona/administración & dosificación , Método Doble Ciego , Femenino , Humanos , Persona de Mediana Edad , Náusea/inducido químicamente , Calidad de Vida , Vómitos/inducido químicamente
2.
Cancer Res ; 52(13): 3593-7, 1992 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-1617630

RESUMEN

A slight induction of granulocytic differentiation of HL-60 cells occurred after treatment with antileukemia chemotherapeutic agents Adriamycin (ADM) and daunomycin (DM). Addition of an inhibitor (sphinganine, SP) of protein kinase C (PKC) enhanced 2-4-fold the ADM or DM-induced differentiation. This phenomenon was accompanied by a slightly augmented antiproliferative effect. The enhancement of differentiation induction in these treatments seemed to be absolute, since the combination treatment (ADM-SP or DM-SP) showed about 2.5-3.6 times as many differentiated cells as the treatment with the anticancer drugs ADM or DM alone. Further characterization of the interaction of ADM and DM with SP on differentiation of HL-60 cells was carried out. Whereas the addition of SP in the fresh medium after the removal of ADM or DM (0.5 h treatment) enhanced the induction of differentiation, a pretreatment (24 h) of the cells with SP followed by continuous exposure to ADM or DM did not show such enhancement effect. The addition of SP at as late as 48 h after the administration of ADM or DM potentiated the induction of differentiation to the same extent as in the simultaneous combination of ADM-SP or DM-SP. Similar results were obtained in the experiments with another PKC inhibitor, staurosporine. These results indicated that inhibition of PKC activities may play an important role in the later events during the induction of differentiation elicited by ADM or DM. The use of the antileukemia drugs ADM and DM in combination with an inhibition of PKC activity results in enhancement of induction of differentiation and suggests a new strategy and a promising approach to the treatment of leukemia.


Asunto(s)
Daunorrubicina/farmacología , Doxorrubicina/farmacología , Leucemia Promielocítica Aguda/patología , Leucemia/tratamiento farmacológico , Esfingosina/análogos & derivados , Diferenciación Celular/efectos de los fármacos , Humanos , Proteína Quinasa C/fisiología , Esfingosina/farmacología , Células Tumorales Cultivadas
3.
Surg Endosc ; 19(12): 1627-30, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16247576

RESUMEN

BACKGROUND: "Three-stitch" laparoscopic Graham patch repair (LGPR) for perforated duodenal ulcer enjoyed the same advantage as open Graham patch repair. However, it was not a popular approach because it had problems of suture entanglement and difficult laparoscopic suturing and knotting. The authors describe their technique and results. METHODS: A prospective series from January 2000 to September 2004 was examined. In this study, 35 LGPRs were performed for 32 males and 3 females with a median age of 47 years (range, 18-76 years). RESULTS: No conversion occurred for any of the 35 LGPRs attempted. The median perforation size was 5 mm (3-10 mm), and the median operative time was 86 min (range, 55-163 min). The median time for ambulation was day 2, and the median time for discharge was day 4. Morbidity was 11%, involving one chest infection, one retention of urine, one pelvic collection, and one pyloric stenosis. There was no reoperation, leakage, or mortality. CONCLUSION: The authors' LGPR technique was safe and efficient, and might be the choice for laparoscopic repair of relatively large perforations.


Asunto(s)
Úlcera Duodenal/complicaciones , Úlcera Duodenal/cirugía , Laparoscopía , Úlcera Péptica Perforada/etiología , Úlcera Péptica Perforada/cirugía , Técnicas de Sutura , Adolescente , Adulto , Anciano , Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
5.
Exp Hematol ; 20(4): 454-61, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1568462

RESUMEN

Induction of differentiation, inhibition of cell growth, and localization of nucleophosmin in HL-60 cells under the treatment of retinoic acid (RA) were studied. Bright nucleolar fluorescence was observed in control promyelocytic growing cells. The addition of RA in the culture system resulted in time- and dose-dependent induction of differentiation, cell growth inhibition, and nucleophosmin translocation from nucleoli to nucleoplasm. Unlike the control cells, many fewer nucleophosmin-associated preribosomal ribonucleoprotein particles (pre-rRNPs) could be obtained from nucleoli of RA-treated cells. Addition of sphinganine, an inhibitor of protein kinase C, facilitated the RA-induced differentiation, nucleophosmin translocation, and cell growth inhibition. Cells treated with sphinganine were more responsive to RA. Differentiation, translocation of nucleophosmin, and inhibition of cell growth occurred with lesser doses of RA or in shorter incubation times in the presence of sphinganine. Significant numbers of HL-60 cells could be rescued from the effects of RA upon the removal of RA after 2-h drug exposure. Pretreatment but not posttreatment of HL-60 cells with sphinganine, however, modulated the reversibility of the effects induced by short-exposure RA treatment. These results indicated that RA therapy can be improved by the pretreatment or the concurrent use of a modulator of protein kinase C activity. Nucleophosmin translocation as observed by immunofluorescence may be a simple and rapid method for assessing inhibition of cellular growth in response to differentiation inducers such as RA in cancer chemotherapy.


Asunto(s)
Diferenciación Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Inhibidores de Crecimiento , Leucemia Mieloide/patología , Proteínas Nucleares/metabolismo , Esfingosina/análogos & derivados , Tretinoina/administración & dosificación , Compartimento Celular/efectos de los fármacos , Esquema de Medicación , Sinergismo Farmacológico , Técnicas In Vitro , Nucleofosmina , Ribonucleoproteínas/metabolismo , Esfingosina/administración & dosificación , Células Tumorales Cultivadas
6.
FEBS Lett ; 318(2): 193-9, 1993 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-7680007

RESUMEN

The efficiency of retinoic acid (RA)-induced differentiation was dependent on the position of HL-60 cells in the cell cycle. Our results demonstrated that cells at the G1/S border were more efficiently induced to differentiate by short exposure to RA than cells at other phases of the cell cycle. Synchronization of cells in G1/S phase by aphidicolin (APH) or mimosine (MIMO) increased the sensitivity of cells to RA short exposure treatment. Pretreatment with sphinganine (SP), a protein kinase C (PKC) inhibitor, potentiated RA-induced cell differentiation. By cell cycle analysis, SP was found to block the cell progression through the G1/S phase. Consequently, cells accumulated in the G1/S phase of the cell cycle. The present data therefore suggest a possible mechanism of action of SP to enhance RA-induced differentiation.


Asunto(s)
Ciclo Celular , Diferenciación Celular/efectos de los fármacos , Granulocitos/citología , Tretinoina/farmacología , Afidicolina/farmacología , Ciclo Celular/efectos de los fármacos , ADN/biosíntesis , Humanos , Técnicas In Vitro , Leucemia Mieloide/patología , Mimosina/farmacología , ARN/biosíntesis , Esfingosina/análogos & derivados , Esfingosina/farmacología , Tretinoina/metabolismo , Células Tumorales Cultivadas
7.
Virus Res ; 77(1): 61-9, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11451488

RESUMEN

Influenza virus assembly and morphogenesis require transport of viral components to the assembly site at the apical plasma membrane of polarized epithelial cells and interaction among the viral components. In this report we have discussed the apical determinants present in the transmembrane domain (TMD) of influenza virus hemagglutinin (HA) and neuraminidase (NA), and the interaction of M1 with influenza virus HA and NA. Earlier studies have shown that the NA and HA TMDs possess determinant(s) for apical sorting and raft-association (Kundu et al., 1996. J. Virol 70, 6508-6515; Lin et al., 1998. J. Cell Biol. 142, 51-57). Analysis of chimeric constructs between NA and TR (human transferring receptor) TMDs and the mutations in the NA and HA TMD sequences showed that the COOH terminus of the NA TMD and NH(2) terminus of the HA TMD encompassing the exoplasmic leaflet of the lipid bilayers were significantly involved in lipid raft-association and that apical determinants were not discrete sequences but rather dispersed within the TMD of HA and NA. These analyses also showed that although both signals for apical sorting and raft-association resided in the NA TMD, they were not identical and varied independently. Interactions of M1 protein with HA or NA, the influenza virus envelope glycoproteins, were investigated by TX-100 detergent treatment of membrane fractions and floatation in sucrose gradients. Results from these analyses showed that the interaction of M1 with mature HA and NA, which associated with the detergent-resistant lipid rafts caused an increased detergent-resistance of the membrane-bound M1 and that M1 interacted with HA and NA both in influenza virus-infected cells as well as in recombinant vaccinia virus-infected cells coexpressing M1 with HA and/or NA. Furthermore, both the cytoplasmic tail and the TMD of HA caused an increased detergent-resistance of the membrane-bound M1 supporting their interaction with M1. Immunofluorescence analysis by confocal microscopy also showed colocalization supporting the interaction of M1 with HA and NA at the cell surface and during exocytic transport both in influenza virus-infected cells as well as in coexpressing cells.


Asunto(s)
Orthomyxoviridae/metabolismo , Proteínas de la Matriz Viral/metabolismo , Proteínas Virales/metabolismo , Ensamble de Virus , Secuencia de Aminoácidos , Animales , Línea Celular , Membrana Celular/metabolismo , Membrana Celular/virología , Polaridad Celular , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Glicoproteínas Hemaglutininas del Virus de la Influenza/metabolismo , Microdominios de Membrana/metabolismo , Datos de Secuencia Molecular , Neuraminidasa/genética , Neuraminidasa/metabolismo
8.
J Biomed Sci ; 2(2): 154-159, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11725051

RESUMEN

Pretreatment of cells with staurosporine, a protein kinase C (PKC) inhibitor, was found to potentiate the granulocytic differentiation induced by a brief (2 h) retinoic acid treatment. By cell cycle analysis, staurosporine was found to have little effect on the cell cycle. Retinoic acid was distributed equally in the nuclei (40%) and in the plasma membrane (40%) of staurosporine-pretreated cells while less than 20% of retinoic acid was found in the membrane of control non-staurosporine-pretreated cells during the retinoic acid-induced differentiation. These results indicate that the enhancing effect of staurosporine may be somehow associated with the localization of retinoic acid in the plasma membrane of the cell. Copyright 1995 S. Karger AG, Basel

9.
J Virol Methods ; 92(1): 83-90, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11164921

RESUMEN

Although hepatitis B virus (HBV) DNA has been detected in the human hepatoma cell line, HAGS 2.1, viral and cellular junction sequences have not been investigated fully. To facilitate the analysis of HBV DNA integration sites in HAGS 2.1 cells, a combination of conventional polymerase chain reaction (PCR) and inverse PCR (IPCR) was carried out to identify the junction between the viral and the cellular gene. The HBV integrant and its cellular counterpart sequence were cloned and analyzed. The sequencing data indicated that the breakpoints on the HBV integrant are at nucleotide 2111 of the C gene and nucleotide 1558 of the X gene. The length of the integrated HBV DNA in HAGS 2.1 was approximately 2.6 kb, which includes partial C, P, and X genes and an intact S gene. The cellular sequence flanking the integrated HBV gene was very similar to a human satellite III repetitive sequence with 43 and 56 of GGAAT repeats on the left- and right-hand side, respectively. Although the findings on the viral-cellular junction in HAGS 2.1 cells cannot explain the liver tumorigenesis, the current study shows that by choosing the nearest restriction site, which can be determined by conventional PCR rather than using a unique site within the integrated viral sequence to do IPCR, gives a higher successful rate for cloning and the subsequent analysis of the viral-cellular junctions.


Asunto(s)
ADN Viral/genética , Virus de la Hepatitis B/genética , Reacción en Cadena de la Polimerasa , Integración Viral , Clonación Molecular , ADN Satélite/efectos de los fármacos , ADN Viral/química , Humanos , Análisis de Secuencia de ADN , Células Tumorales Cultivadas
10.
Life Sci ; 51(6): 415-22, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1635422

RESUMEN

The differentiation of HL-60 promyelocytic cells toward mature granulocytic cells induced by retinoic acid (RA) was accompanied by a decrease in protein kinase C (PKC) activity. The enhancement of RA-induced differentiation and the potentiation of the decrease of PKC activity by sphinganine (SP) seemed to correlate with each other. Kinetically, PKC activity during RA-induced differentiation without SP decreased to its lowest (75% of the control) after 48h; about 50% of the reduction was observed at 24h. In the presence of SP, PKC activity decreased more rapidly to its lowest (60% of the control) within 24h of incubation of RA. SP, added 24h before or concomitantly with the addition of RA, could potentiate the RA-induced differentiation and the reduction of PKC activity. Our results indicate that the effect of SP and the role of PKC during RA-induced differentiation may be critical at the early stages of induction of differentiation (within 24h of RA exposure).


Asunto(s)
Granulocitos/enzimología , Leucemia Promielocítica Aguda/enzimología , Proteína Quinasa C/metabolismo , Esfingosina/análogos & derivados , Tretinoina/farmacología , Diferenciación Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Línea Celular , Sinergismo Farmacológico , Granulocitos/citología , Granulocitos/efectos de los fármacos , Humanos , Leucemia Promielocítica Aguda/tratamiento farmacológico , Leucemia Promielocítica Aguda/metabolismo , Esfingosina/metabolismo , Esfingosina/farmacología , Células Tumorales Cultivadas
11.
Life Sci ; 51(12): 915-20, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1518368

RESUMEN

HeLa nucleoli were isolated using the NP-40 method and subsequently extracted with 3M urea. The extract was incubated at 60 degrees C for 30 min, and precipitated proteins were removed by centrifugation. The supernatant was analyzed by one- and two-dimensional SDS polyacrylamide gel electrophoresis (PAGE). Protein B23 was the only major protein extracted from HeLa nucleoli by this procedure. Using this procedure, 1 mg of protein B23 was obtained from 2 g of HeLa cells. The purity of the extracted protein B23 was 98%, as measured by one- and two-dimensional gel electrophoresis.


Asunto(s)
Nucléolo Celular/química , Proteínas Nucleares/aislamiento & purificación , Centrifugación , Electroforesis en Gel Bidimensional , Células HeLa/química , Humanos , Punto Isoeléctrico , Peso Molecular , Nucleofosmina , Fosfoproteínas/aislamiento & purificación , Urea
12.
Life Sci ; 52(25): 2035-43, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8502130

RESUMEN

Sphinganine (SP) pre-treatment potentiated the retinoic acid (RA)-induced (4-96h exposures) differentiation and increase of alkaline phosphatase (ALP) activity. A higher percentage of SP pre-treated cells in RA exposures resembled mature myelocytes or granulocytes; greater increase in ALP activity was observed. In cells exposed to RA alone for only a period of 24h, the ALP activity could still increase and reach a similar maximum ALP activity (8.5-10.0 units/mg protein) at 48h as it was under continuous RA treatment. In all cells with longer exposures (24-96h) to RA, SP pre-treatment increased ALP activity to more or less the same higher maximum (14.0-15.5 units/mg protein). SP, added 24h before or concomitantly, but not 24 nor 48h after the addition of RA, could potentiate the RA-induced differentiation and increase of ALP activity.


Asunto(s)
Fosfatasa Alcalina/metabolismo , Diferenciación Celular/efectos de los fármacos , Esfingosina/análogos & derivados , Tretinoina/farmacología , Línea Celular , Sinergismo Farmacológico , Humanos , Cinética , Leucemia Promielocítica Aguda , Esfingosina/farmacología , Factores de Tiempo , Células Tumorales Cultivadas
13.
Br J Educ Psychol ; 65 ( Pt 1): 15-25, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7727264

RESUMEN

The tripartite components of burnout and eight coping strategies were assessed in a sample of 415 Chinese secondary school teachers in Hong Kong. While emotional exhaustion and depersonalisation were relatively undifferentiated among these teachers, a reduced sense of accomplishment as a distinct component of burnout was generally reported. The findings that avoidant coping strategies were consistently related to all three aspects of burnout suggested that teachers employing escape-avoidance to cope with stressors might be more prone to burnout. Implications for promoting certain patterns of coping to combat burnout were discussed.


Asunto(s)
Adaptación Psicológica , Agotamiento Profesional/psicología , Comparación Transcultural , Enseñanza , Adulto , Agotamiento Profesional/etnología , Agotamiento Profesional/prevención & control , Femenino , Hong Kong , Humanos , Satisfacción en el Trabajo , Masculino , Persona de Mediana Edad
14.
J Adolesc ; 23(2): 189-203, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10831142

RESUMEN

This study investigated the personal concerns and causes of difficulties perceived by Hong Kong adolescent students. A survey of 2103 secondary school students in Year 1 to Year 3 indicated that both students' concerns and causes are multi-dimensional. Academic achievement was perceived as the most pressing concern, while problems at home and maladjusted behaviour were seen as lesser concerns. Students attributed their difficulties more to personal deficiencies, and least to family factors. Results also showed significant gender, age and school banding effects. Implications of the findings for educationalists and psychologists working with adolescents in school contexts are discussed.


Asunto(s)
Adaptación Psicológica , Psicología del Adolescente , Estudiantes/psicología , Logro , Adolescente , Factores de Edad , Análisis de Varianza , Niño , China/etnología , Análisis Factorial , Femenino , Hong Kong , Humanos , Relaciones Interpersonales , Masculino , Grupo Paritario , Autoimagen , Factores Sexuales , Factores Socioeconómicos
15.
Cell Mol Life Sci ; 59(6): 920-31, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12169022

RESUMEN

Many purified virions, particularly enveloped virus particles (such as retrovirus, hepadnavirus, herpesvirus, orthomyxovirus, and paramyxovirus), contain protein kinase (PK) activity. This type of PK has been called virion-associated protein kinase (VAPK). Even though some VAPKs are identified either as a cellular PK or viral-encoded kinase, many remain to be identified. Although the roles of VAPKs are not yet well characterized, there is ample evidence to suggest their importance in viral infectivity, uncoating, transcription, and replication.


Asunto(s)
Proteínas Quinasas/fisiología , Virión/enzimología , Animales , Virus ADN/enzimología , Humanos , Virus de Insectos/enzimología , Virus de Plantas/enzimología , Virus ARN/enzimología
16.
Biochem Biophys Res Commun ; 196(3): 1390-400, 1993 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-8250895

RESUMEN

Differential changes in the expression of PKC isoenzymes in the RA-induced differentiation were noted. As measured by Western blot analysis, our results indicated the expressions of PKC-alpha, and -beta isoenzymes decreased in the cell membrane but increased in the cytosol during the RA-induced granulocytic differentiation. The amounts of PKC-gamma, on the other hand, decreased in the cell membrane while there was no significant changes in the cytosol. Similarly, the expression of PKC-delta was not altered in the cytosol, but was slightly reduced during the SP enhancement of RA-induced differentiation. In contrast, there were virtually little changes in the expression of PKC-epsilon and -zeta in the cell membrane or in the cytosol during the RA-induced differentiation in the absence or presence of SP. Concomitant with the decreased total PKC activity, there was a decline in the generation of sn-1,2-diacylglycerol (DAG) during the RA-induced differentiation. SP, enhancing the RA-induced differentiation, also potentiated the decrease of DAG content.


Asunto(s)
Diferenciación Celular/fisiología , Granulocitos/citología , Isoenzimas/metabolismo , Proteína Quinasa C/metabolismo , Esfingosina/análogos & derivados , Tretinoina/farmacología , Western Blotting , Diferenciación Celular/efectos de los fármacos , Línea Celular , Diglicéridos/metabolismo , Sinergismo Farmacológico , Electroforesis en Gel de Poliacrilamida , Granulocitos/efectos de los fármacos , Granulocitos/enzimología , Humanos , Isoenzimas/aislamiento & purificación , Leucemia Promielocítica Aguda , Proteína Quinasa C/aislamiento & purificación , Esfingosina/farmacología , Células Tumorales Cultivadas
17.
Virology ; 290(2): 329-41, 2001 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-11883197

RESUMEN

Influenza viruses bud from the plasma membrane of virus-infected cells. Although budding is a critical step in virus replication, little is known about the requirements of the budding process. In this report, we have investigated the role of ATP in influenza virus budding by treating influenza virus infected Madin-Darby canine kidney (MDCK) cells with a number of metabolic inhibitors. When WSN virus-infected MDCK cells were exposed to antimycin A, carbonyl cyanide m-chlorophenylhydrazone, carbonyl cyanide p-trifluoromethoxy-phenylhydrazone, or oligomycin for a short time (15 min or 1 h) late in the infectious cycle, the rate of virus budding decreased. This inhibitory effect was reversible upon removal of the inhibitors. The role of ATP hydrolysis was analyzed by treating lysophosphatidylcholine (LPC)-permeabilized live filter-grown virus-infected MDCK cells with nonpermeable ATP analogues from the basal side and assaying virus budding from the apical side. In LPC-permeabilized cells, membrane-impermeable ATP analogues such as adenosine 5'-O-(3-thiotriphosphate) or 5'-adenylylimidodiphosphate caused reduction of virus budding which could be partially restored by adding excess ATP. These data demonstrated that ATP hydrolysis and not just ATP binding was required for virus budding. However, inhibitors of ion channel (ATPases) and protein ubiquitinylation, which also required the ATP as energy source, did not affect influenza virus budding, suggesting that neither ion channel nor protein ubiquitinylation activity was involved in influenza virus budding. On the other hand, treatment with dimethyl sulfoxide (DMSO), which decreases membrane viscosity, reduced the rate of virus budding, demonstrating that the physical state of membrane viscosity and membrane fluidity had an important effect on virus budding. Data presented in the report indicate that influenza virus budding is an active ATP-dependent process and suggest that reduced virus budding by ATP depletion and DMSO treatment may be partly due to decreased membrane viscosity.


Asunto(s)
Acetilcisteína/análogos & derivados , Adenosina Trifosfato/fisiología , Virus de la Influenza A/fisiología , Acetilcisteína/farmacología , Adenosina Trifosfato/análogos & derivados , Adenosina Trifosfato/antagonistas & inhibidores , Animales , ATPasas Transportadoras de Calcio/antagonistas & inhibidores , Línea Celular , Permeabilidad de la Membrana Celular , Cisteína Endopeptidasas , Inhibidores de Cisteína Proteinasa/farmacología , Perros , Inhibidores Enzimáticos/farmacología , Humanos , Indoles/farmacología , Cinética , Leupeptinas/farmacología , Lisofosfatidilcolinas/farmacología , Complejos Multienzimáticos/antagonistas & inhibidores , Oligopéptidos/farmacología , Ouabaína/farmacología , Complejo de la Endopetidasa Proteasomal , ATPasa Intercambiadora de Sodio-Potasio/antagonistas & inhibidores , Sulfonas/farmacología , Tapsigargina/farmacología , Viscosidad
18.
Virus Genes ; 16(2): 147-8, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9608658

RESUMEN

The latency associated transcript (LAT) of herpes simplex virus (HSV) appears to exist as an RNA molecule only. This phenomenon is consistent with the concept of functioning at an RNA level, and several lines of evidence suggest that the LAT may be a ribozyme. This provides an insight into understanding the role of LAT during HSV reactivation.


Asunto(s)
Herpesvirus Humano 1/fisiología , Herpesvirus Humano 2/fisiología , ARN Catalítico/fisiología , Activación Viral/fisiología , Latencia del Virus/fisiología , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/crecimiento & desarrollo , Herpesvirus Humano 2/genética , Herpesvirus Humano 2/crecimiento & desarrollo , Humanos , ARN Viral/fisiología
19.
Cell Mol Life Sci ; 54(12): 1403-11, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9893713

RESUMEN

Many virus and transposon DNAs can integrate into the host genome. In this review, techniques, including inverse polymerase chain reaction (IPCR), novel Alu-PCR and vectorette- or splinkerette-PCR are introduced as possible strategies for cloning flanking DNA regions of the integrants. Targeted gene-walking PCR, restriction-site PCR, capture PCR, and panhandle PCR and boomerang DNA amplification are also described. The principles, advantages and limitations of each approach are discussed.


Asunto(s)
Clonación Molecular/métodos , ADN Viral/genética , Animales , ADN Viral/análisis , Humanos , Reacción en Cadena de la Polimerasa/métodos , Análisis de Secuencia de ADN
20.
Biochem Biophys Res Commun ; 199(2): 888-96, 1994 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-8135836

RESUMEN

The differentiation of HL-60 promyelocytic cells toward mature granulocytic cells induced by dimethyl sulfoxide (DMSO) was accompanied by a quantitative similar increase in alkaline phosphatase (ALP) activity and decrease in protein kinase C (PKC) activity. The combination of DMSO and sphinganine (SP), a potent inhibitor of PKC, increased in parallel the percentage of mature cells and the ALP activity. The enhancement of DMSO-induced differentiation and the potentiation of the decrease of PKC activity by SP also seemed to correlate with each other. Our results indicate that both ALP and PKC may play a role in the DMSO-induced granulocytic differentiation.


Asunto(s)
Fosfatasa Alcalina/metabolismo , Diferenciación Celular/efectos de los fármacos , Dimetilsulfóxido/farmacología , Granulocitos/citología , Proteína Quinasa C/metabolismo , Esfingosina/análogos & derivados , Fosfatasa Alcalina/aislamiento & purificación , Línea Celular , Sinergismo Farmacológico , Granulocitos/efectos de los fármacos , Humanos , Cinética , Leucemia Promielocítica Aguda , Proteína Quinasa C/aislamiento & purificación , Esfingosina/farmacología , Factores de Tiempo , Células Tumorales Cultivadas
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