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1.
J Minim Invasive Gynecol ; 21(2): 245-51, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24126261

RESUMEN

STUDY OBJECTIVE: To identify factors that might contribute to pregnancies reported after hysteroscopic sterilization worldwide. DESIGN: Retrospective review of commercial data compiled from the MAUDE database, medical literature, and manufacturer reports received during commercial distribution of hysteroscopic sterilization micro-inserts from 2001 through 2010 (Canadian Taskforce classification III descriptive study). MEASUREMENTS AND MAIN RESULTS: From 2001 through 2010, 497 305 hysteroscopic sterilization kits were distributed worldwide, and 748 pregnancies were reported, i.e., 0.15% of the estimated user population based on the number of distributed kits. The data were sufficient to enable analysis of 508 pregnancies for potential contributing factors and showed most to be associated with patient or physician noncompliance (n = 264) or misinterpreted confirmation tests (n = 212). Conceptions deemed to have occurred within 2 weeks of the procedure and therefore too early for detection were identified in 32 cases. CONCLUSION: Although there are limitations to the dataset and the study design is retrospective, it represents the largest body of cumulative hysteroscopic sterilization data available to date. Of the 748 pregnancies reported, it is apparent that some might have been prevented with greater patient and clinician attention to interim contraceptive use and counseling and with more rigorous evaluation and informed interpretation of the procedure confirmation tests. Although the estimated pregnancy rate based on such a dataset is likely an underestimation, it does suggest that the evaluable field performance of hysteroscopic sterilization micro-inserts is consistent with the labeled age-adjusted effectiveness of 99.74% at 5 years.


Asunto(s)
Histeroscopía/métodos , Evaluación de Resultado en la Atención de Salud , Esterilización Tubaria/estadística & datos numéricos , Adulto , Bases de Datos Factuales , Femenino , Salud Global , Humanos , Cooperación del Paciente , Embarazo , Índice de Embarazo , Estudios Retrospectivos , Esterilización Reproductiva/estadística & datos numéricos , Salud de la Mujer
2.
Science ; 280(5366): 1073-7, 1998 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-9582120

RESUMEN

Detection of human immunodeficiency virus-type 1 (HIV-1) on only one or a few occasions in infants born to infected mothers has been interpreted to indicate that infection may be transient rather than persistent. Forty-two cases of suspected transient HIV-1 viremia among 1562 perinatally exposed seroreverting infants and one mother were reanalyzed. HIV-1 env sequences were not found in specimens from 20; in specimens from 6, somatic genetic analysis revealed that specimens were mistakenly attributed to an infant; and in specimens from 17, phylogenetic analysis failed to demonstrate the expected linkage between the infant's and the mother's virus. These findings argue that transient HIV-1 infection, if it exists, will only rarely be satisfactorily documented.


Asunto(s)
Infecciones por VIH/virología , VIH-1/genética , VIH-1/aislamiento & purificación , Manejo de Especímenes , ADN Viral/análisis , ADN Viral/genética , Errores Diagnósticos , Contaminación de Equipos , Femenino , Genes env , Infecciones por VIH/inmunología , Infecciones por VIH/transmisión , Humanos , Lactante , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , ARN Viral/análisis , Linfocitos T Citotóxicos/inmunología , Viremia/virología
3.
J Clin Invest ; 88(2): 505-11, 1991 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1677945

RESUMEN

Human mononuclear leukocytes (MNL) exposed to respiratory syncytial virus (RSV) produce net IL-1 inhibitor bioactivity with the anticipated consequences of cell cycle arrest, suppressed virus-specific proliferation, and reduced expression of activation markers. These studies were undertaken to investigate effects of exposure and resultant net IL-1 inhibitor activity on the expression of the intercellular adhesion molecule-1 (ICAM-1), and its ligand the lymphocyte function-associated antigen (LFA-1). MNL collected at 1, 4, and 24 h after exposure to influenza virus (which induces net IL-1 bioactivity) showed enhanced expression of ICAM-1 and LFA-1 relative to sham-exposed MNL and exhibited cell clustering. In contrast, exposure to RSV was associated with suppressed expression of both ICAM-1 and LFA-1 and with minimal detectable cell clustering throughout the culture period. Influenza virus-exposed MNL produced significantly more IL-1 and IFN-gamma (which require cell-cell collaboration for optimal production) than did RSV-exposed MNL. These data raise the possibility that exposure of MNL to RSV fails to elicit or blocks the early events necessary for cellular collaboration, contributing to early suppression of the clonal expansion of RSV-specific lymphocytes.


Asunto(s)
Antígenos CD/biosíntesis , Moléculas de Adhesión Celular/biosíntesis , Leucocitos Mononucleares/inmunología , Antígeno-1 Asociado a Función de Linfocito/biosíntesis , Orthomyxoviridae/inmunología , Virus Sincitiales Respiratorios/inmunología , Adulto , Comunicación Celular , Células Cultivadas , Humanos , Molécula 1 de Adhesión Intercelular , Interferón gamma/biosíntesis , Interleucina-1/biosíntesis , Leucocitos Mononucleares/microbiología
4.
Mol Endocrinol ; 10(11): 1350-7, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8923461

RESUMEN

Expression of aromatase P450 (P450arom; the product of the CYP19 gene) in human adipose stromal cells in primary culture is markedly stimulated by serum in the presence of dexamethasone (DEX). Under these conditions, the majority of P450arom transcripts contain untranslated exon 1.4 at their 5'-ends. Previously, we observed that the region of the CYP19 gene upstream of exon 1.4 contains a TATA-less promoter, a glucocorticoid response element, and an interferon-gamma-activating sequence. These act to mediate the action of interleukin-6 and related cytokines to stimulate aromatase expression in the presence of DEX. In the present study, we found that tumor necrosis factor-alpha (TNF alpha) also acts synergistically with DEX to stimulate aromatase expression in adipose stromal cells in serum-free medium. We observed that the action of TNF alpha can be mimicked by ceramide. Maximal aromatase activity was obtained when cells were incubated with 5 ng/ml TNF alpha or 100 nM ceramide in the presence of 250 nM DEX. Levels of c-fos and c-jun proteins also were increased by TNF alpha or ceramide in the presence of DEX. Upstream of the interferon-gamma-activating sequence site there is an imperfect activating protein-1 (AP-1) binding site (2-bp mismatch). Gel retardation analysis using nucleotide probes containing the putative AP-1-binding sequence and nuclear extracts of human adipose stromal cells cultured in the presence of TNF alpha or ceramide plus DEX revealed that adipose stromal cells nuclear proteins bind to this site and that binding was competed by a 100-fold excess of a consensus AP-1 sequence. In addition, binding activity was competed by both anti-c-fos and anti-c-jun sera. Mutation or deletion of the putative AP-1 element resulted in the loss of TNF alpha- plus DEX-induced activity of reporter constructs comprised of 515 bp of the exon 1.4 flanking sequence linked to the luciferase gene. These results suggest that TNF alpha, probably acting through ceramide formation, stimulates the binding of both c-fos and c-jun to the AP-1 element upstream of exon 1.4. These act cooperatively with the ligand-activated glucocorticoid receptor to induce aromatase expression in adipose stromal cells in primary culture. We conclude that this TNF alpha signal transduction pathway may play an important role in the regulation of estrogen biosynthesis in adipose tissue.


Asunto(s)
Tejido Adiposo/citología , Aromatasa/genética , Células del Estroma/enzimología , Factor de Transcripción AP-1/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Tejido Adiposo/efectos de los fármacos , Administración Tópica , Antiinflamatorios/farmacología , Antineoplásicos Hormonales/farmacología , Aromatasa/efectos de los fármacos , Sitios de Unión , Células Cultivadas , Ceramidas/farmacología , Dexametasona/farmacología , Sinergismo Farmacológico , Femenino , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Genes Reporteros , Glucocorticoides , Humanos , Luciferasas/efectos de los fármacos , Luciferasas/genética , Regiones Promotoras Genéticas , Biosíntesis de Proteínas , Proteínas Proto-Oncogénicas c-fos/efectos de los fármacos , Proteínas Proto-Oncogénicas c-fos/genética , Proteínas Proto-Oncogénicas c-fos/metabolismo , Proteínas Proto-Oncogénicas c-jun/efectos de los fármacos , Proteínas Proto-Oncogénicas c-jun/genética , Proteínas Proto-Oncogénicas c-jun/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Células del Estroma/efectos de los fármacos , Factor de Transcripción AP-1/genética , Transcripción Genética/efectos de los fármacos
5.
J Leukoc Biol ; 46(3): 189-98, 1989 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2788203

RESUMEN

Net interleukin-1 (IL-1) inhibitor activity is induced by exposure of purified human monocytes-macrophages to respiratory syncytial virus (RSV). Furthermore, IL-1 inhibitor activity was produced by monocytes-macrophages exposed to RSV in the presence of lymphocytes, that is, by unseparated mononuclear leukocytes (MNL). Purified RSV-exposed lymphocytes, as well as the lymphocytes exposed within MNL preparations, produced net IL-1 inhibitor activity. In contrast, net IL-1 activity was produced when purified monocytes-macrophages or unseparated MNL were exposed to influenza virus. The RSV-induced IL-1 inhibitors demonstrated antiproliferative effects on mitogen-stimulated human lymphocytes as well as on the mouse thymocytes used in standard assays. The results raise the possibility that such antiproliferative activity is mediated, at least in part, by monocytes-macrophages. The data also suggest that IL-1 inhibitors produced by MNL after exposure to RSV may contribute along with other factors to the recurrence of RSV infection in immune individuals.


Asunto(s)
Interleucina-1/antagonistas & inhibidores , Leucocitos Mononucleares/inmunología , Linfocinas/biosíntesis , Orthomyxoviridae/inmunología , Virus Sincitiales Respiratorios/inmunología , Humanos , Interleucina-1/metabolismo , Leucocitos Mononucleares/metabolismo , Infecciones por Respirovirus/inmunología
6.
Mol Cell Endocrinol ; 118(1-2): 215-20, 1996 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-8735608

RESUMEN

The expression of transcripts of cytokines of the interleukin-6 (IL-6) family has been examined in human breast tumors, breast cancer cell lines, and adipose stromal cells, by means of reverse transcription polymerase chain reaction amplification. Of the six breast tumor samples examined, all expressed transcripts encoding IL-6 and Leukemia Inhibitory Factor (LIF). Four of the samples also expressed transcripts for oncostatin M (OSM) and IL-11, and three expressed the IL-6 receptor. Adipose stromal cells expressed IL-6, IL-11 and LIF, but not the IL-6 receptor, consistent with previous conclusions that IL-6 activity in these cells required addition of IL-6 soluble receptor. In the case of T47D cells, expression of IL-11 protein was confirmed by immunotitration. Moreover, in these cells, expression of IL-11 transcripts was induced 3-fold by addition of estradiol to the culture medium. These results add credence to our previous proposal that breast cancer development is regulated in part by local autocrine and paracrine mechanisms via epithelial/mesenchymal interactions, in which estrogen produced by stromal cells surrounding the tumor acts to stimulate the production of growth factors and cytokines by the tumor cells. Some of these may act to stimulate further the growth and development of the tumor, while these or other factors may act on the surrounding mesenchymal cells in a paracrine fashion to stimulate aromatase expression in the presence of glucocorticoids. Thus, a positive feedback loop is established which leads to the development and growth of the tumor.


Asunto(s)
Tejido Adiposo/inmunología , Neoplasias de la Mama/inmunología , Citocinas/genética , Interleucina-6/genética , Tejido Adiposo/metabolismo , Antígenos CD/genética , Antígenos CD/inmunología , Aromatasa/metabolismo , Neoplasias de la Mama/genética , Medios de Cultivo Condicionados , Citocinas/inmunología , Estradiol/farmacología , Femenino , Expresión Génica , Inhibidores de Crecimiento/genética , Inhibidores de Crecimiento/inmunología , Humanos , Interleucina-11/genética , Interleucina-11/inmunología , Interleucina-6/biosíntesis , Factor Inhibidor de Leucemia , Linfocinas/genética , Linfocinas/inmunología , Oncostatina M , Péptidos/genética , Péptidos/inmunología , Reacción en Cadena de la Polimerasa , ADN Polimerasa Dirigida por ARN , Receptores de Interleucina/genética , Receptores de Interleucina/inmunología , Receptores de Interleucina-6 , Células del Estroma/inmunología , Células del Estroma/metabolismo , Células Tumorales Cultivadas
7.
Fertil Steril ; 76(1): 80-4, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11438323

RESUMEN

OBJECTIVE: To compare IVF outcomes between infertile African American and white women. DESIGN: Retrospective cohort study. SETTING: Hospital-based IVF practice. PATIENT(S): Women undergoing IVF procedures between November 1996 and June 2000. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Implantation and pregnancy rates. RESULT(S): There were 24 African American and 273 white women < or =40 years of age who underwent 25 and 333 IVF cycles, respectively. African American women were more likely to have had tubal factor as a primary diagnosis, to have had a child, and to have undergone fewer previous assisted reproductive technology (ART) cycles as compared to white women. No differences between the two groups for clinical variables were noted with the exception of body mass index (BMI [kg/m(2)], 27.1 in African Americans vs. 24.8 in whites). Implantation rates were higher in African American than in white women (35% vs. 23%, respectively). Pregnancy rates were 71% in African Americans and 48% in whites. After adjustment for tubal factor, BMI, and parity, the odds ratio for pregnancy in African American women versus white women increased from 2.6 to 3.3. CONCLUSION(S): This is the first study to demonstrate a significantly higher clinical pregnancy rate in African American women as compared to white women undergoing ART. These data strongly contradict a recent study comparing the same two groups of women undergoing ART. We urge other ART centers to report their data pertaining to race.


Asunto(s)
Negro o Afroamericano/estadística & datos numéricos , Implantación del Embrión , Índice de Embarazo , Técnicas Reproductivas , Población Blanca/estadística & datos numéricos , Adulto , Estudios de Cohortes , Femenino , Humanos , Oportunidad Relativa , Embarazo , Estudios Retrospectivos
8.
J Soc Gynecol Investig ; 2(1): 45-50, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-9420848

RESUMEN

OBJECTIVE: To determine whether serum-free (SF) conditioned media (CM) from several human breast cancer cell lines and primary stromal cell cultures contain factor(s) that mimic the marked stimulatory effects of serum on aromatase activity and aromatase P450 (P450arom) gene expression in adipose stromal cells in culture (ASC) in the presence of dexamethasone (DEX). METHODS: Adipose stromal cells, harvested from fresh adipose specimens, were grown to confluence, switched to SF media, and then incubated in the presence or absence of DEX with CM from T47-D breast cancer cells, pre-treated with or without 17 beta-estradiol (E2), and with CM from stromal cell cultures. Aromatase activity of the ASC was determined by the [3H] water release assay. Total RNA was isolated, and reverse transcription-polymerase chain reaction was performed to determine the expression of various 5'-termini. RESULTS: T47-D CM stimulated aromatase activity in a concentration-dependent manner, similar to that of serum, in ASC incubated with DEX. Estrogen potentiated this in a dose-dependent fashion. The ASC CM and endometrial stromal cell CM also markedly induced aromatase activity in ASC. Heat inactivation destroyed the stimulating ability of CM. The majority of P450arom 5'-termini expressed by ASC incubated with CM plus DEX contained the promoter I.4-specific sequence. CONCLUSIONS: Conditioned media from several breast cancer cell lines and primary stromal cell cultures can mimic the effects of serum in the presence of DEX to stimulate aromatase activity in ASC. These results suggest that undefined, heat-labile and proteinaceous factors are present in CM that stimulate P450arom expression in a fashion similar to that of serum.


Asunto(s)
Tejido Adiposo/citología , Tejido Adiposo/enzimología , Aromatasa/biosíntesis , Neoplasias de la Mama , Medios de Cultivo Condicionados , Medio de Cultivo Libre de Suero , Cartilla de ADN , Dexametasona/farmacología , Estradiol/análogos & derivados , Estradiol/farmacología , Antagonistas de Estrógenos/farmacología , Femenino , Fulvestrant , Humanos , Reacción en Cadena de la Polimerasa , Células del Estroma/enzimología , Células Tumorales Cultivadas
11.
J Am Dent Assoc ; 86(6): 1222, 1973 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-4512730
12.
J Med Virol ; 27(3): 179-87, 1989 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2786050

RESUMEN

Previous studies demonstrated that in vitro infection with influenza A viruses altered several functions of human monocytes-macrophages but did not detectably alter functions of human lymphocytes. However, both types of cells were infected, as determined by production and surface expression of viral antigens. In the current studies, human mononuclear leukocytes were infected in vitro and assayed for both influenza virus-induced proliferation and mitogen (phytohemagglutinin [PHAl)-induced proliferation, as well as for ability to stimulate proliferative responses by normal autologous leukocytes. The leukocytes showed proliferation in response to the infectious virus, but concomitant depressed proliferative responses to PHA. Coculture experiments suggested suppression of PHA-induced responses by the virus-infected cells. However, upon coculture with fresh autologous leukocytes (without PHA stimulation), both virus-infected macrophages and virus-infected lymphocytes induced autologous lymphocyte proliferative responses. Altered proliferative responses to mitogen stimulation after exposure to the virus were not due to diminished interleukin-1 production or diminished expression of HLA-DR by monocytes-macrophages. The expression of influenza virus antigens and resulting induction of autologous proliferative responses, combined with depressed mitogen-induced proliferation, may be important in human antiviral defense.


Asunto(s)
Virus de la Influenza A/fisiología , Leucocitos Mononucleares/citología , Activación de Linfocitos , Adulto , Células Presentadoras de Antígenos/inmunología , Antígenos Virales/inmunología , Células Cultivadas , Concanavalina A/farmacología , Femenino , Antígenos HLA-DR/biosíntesis , Humanos , Interleucina-1/biosíntesis , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/microbiología , Activación de Linfocitos/efectos de los fármacos , Linfocitos/citología , Linfocitos/inmunología , Linfocitos/microbiología , Macrófagos/inmunología , Macrófagos/microbiología , Masculino , Monocitos/microbiología , Fitohemaglutininas/farmacología
13.
J Clin Ultrasound ; 21(3): 171-4, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8382218

RESUMEN

The recognition of peritoneal fluid is of considerable clinical importance; however, the sensitivity of modern techniques for the detection of this finding has not been determined. The purpose of this study was to assess the utility of transvaginal sonography for the detection of free peritoneal fluid. Nineteen infertile women scheduled to undergo diagnostic laparoscopy were scanned with a 5-MHz transvaginal probe just before the surgical procedure. Peritoneal fluid was then aspirated laparoscopically, and the volume and location was compared to the sonographic findings. The volume of fluid obtained at laparoscopy ranged from 0 mL to 45 mL (median 8 mL). All patients with fluid volumes > or = 0.8 mL had free fluid identified sonographically. The location of fluid observed sonographically corresponded to that noted at laparoscopy in all cases. Free peritoneal fluid was visualized in 8 (73%) of 11 patients with regular menstrual cycles who were in the follicular phase at the time of the study. We conclude that transvaginal sonography is a sensitive and reliable method for the detection of free peritoneal fluid in anatomically normal women. This finding should not necessarily be considered abnormal, at least in women of reproductive age, nor should it be considered diagnostic of oocyte release.


Asunto(s)
Líquido Ascítico/diagnóstico por imagen , Femenino , Humanos , Infertilidad Femenina/diagnóstico , Infertilidad Femenina/diagnóstico por imagen , Laparoscopía , Ciclo Menstrual/fisiología , Ovulación/fisiología , Sensibilidad y Especificidad , Ultrasonografía/métodos
14.
J Food Prot ; 43(7): 514-519, 1980 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30822958

RESUMEN

Electrical stimulation of prerigor beef carcasses produced a rapid initial drop in pH of longissimus muscles excised and vacuum-packaged at 1, 2 or 4 h postmortem. This initial drop was further increased by delayed excision and was severe enough that even -30-C storage did not retard the overall decline. Through the first 10 h of the 30-h sampling period at -30 C, pH was higher for nonstimulated than for stimulated muscle and was substantially affected by the time of muscle excision. Compared to -30-C storage, a 3-C storage temperature resulted in an even faster decline of pH in electrically stimulated muscle but still hindered the decline in nonstimulated muscle. Although the decline in pH was affected by electrical stimulation, excision time and storage method, initial (time of excision) and final (5 days postmortem) sarcomere length were not. Electrical stimulation of prerigor beef carcasses did not affect the appearance of hot-boned or cold-boned longissimus or semimembranosus muscles. Excision time, however, did affect the color and color uniformity of semimembranosus muscles, apparently because of alteration of the temperature and pH relationship. Excision times of 1 or 2 h appear preferable to 4 or 48 h because combinations of high temperature and low pH within deeper areas of the carcass could cause severe non-uniformity of color in muscles set deep within the carcass.

15.
Artículo en Inglés | MEDLINE | ID: mdl-1146011

RESUMEN

The composite findings described above suggest that the relatively mild blood trauma (and possibly altered arterial pulse waveforms), which were produced during the prolonged pump perfusions, sufficed to produce a modest but distinct measure of compromise in the phagocytic function of the RES in the majority of animals. Among possible factors contributing to the observed decreases in the RES phagocytic function of perfused animals are 1) pump-induced alteration of blood flow pattern RES elements (particularly decreased hepatic perfusion), 2) impaired opsonization, and 3) depressed phagocytic capability of RES cellular elements (due possibly to partial RES blockade by blood breakdown products. The specific role of these and possibly other factors requires furher clarification. The findings thus suggest that fixed tissue elements, as well as circulating blood cells, may be vulnerable to the hematological, and possibly the hemodynamic derangements which accompany prolonged perfusion with mechanical circulatory devices.


Asunto(s)
Máquina Corazón-Pulmón , Sistema Mononuclear Fagocítico/citología , Fagocitosis , Animales , Recuento de Células Sanguíneas , Plaquetas , Presión Sanguínea , Carbono/sangre , Perros , Hematócrito , Hemoglobinas/análisis , Macrófagos del Hígado/fisiología , Recuento de Leucocitos , Hígado/citología , Macrófagos/fisiología , Masculino , Sistema Porta
16.
Clin Diagn Lab Immunol ; 1(5): 487-92, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8556490

RESUMEN

The feasibility of measuring virus-specific human cytotoxic T-lymphocyte (CTL) activity by using cryopreserved mononuclear leukocytes to support clinical vaccine trials was addressed. Autologous fresh and cryopreserved cells from the same sample of peripheral blood were used as sources of CTL precursors and were tested for influenza virus-specific activity. The data indicated that virus-specific CTL activity could be measured by using cryopreserved cells; this could also be done in assays that are designed to characterize the responsible effector cell population.


Asunto(s)
Criopreservación , Gripe Humana/prevención & control , Linfocitos T Citotóxicos/inmunología , Vacunas Virales/inmunología , Femenino , Humanos , Inmunofenotipificación , Gripe Humana/inmunología , Gripe Humana/virología , Leucocitos Mononucleares/virología , Masculino , Reproducibilidad de los Resultados , Linfocitos T Citotóxicos/virología
17.
Vaccine ; 11(1): 36-42, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8427035

RESUMEN

Interactions between influenza viruses and human macrophages were examined to detect potential mechanisms for enhanced febrile reactions previously associated with administration of an avian-human H1N1 reassortant vaccine. Cells exposed to that strain were compared with cells exposed to wild-type and cold-adapted H1H1 and H3H2 strains and an avian-human H3N2 strain. Cells exposed to the avian-human H1N1 virus showed increased synthesis of viral neuraminidase, previously reported to induce fever-producing cytokines, but no detectable increase in production of interleukin-1 beta, interleukin-6 and tumour necrosis factor-alpha measured by immunoassay, or decrease in interleukin-1 inhibitor activity by bioassay.


Asunto(s)
Vacunas contra la Influenza/farmacología , Macrófagos/inmunología , Orthomyxoviridae/inmunología , Fiebre/etiología , Humanos , Técnicas In Vitro , Vacunas contra la Influenza/efectos adversos , Interleucina-1/antagonistas & inhibidores , Interleucina-1/biosíntesis , Interleucina-6/biosíntesis , Linfocinas/biosíntesis , Neuraminidasa/biosíntesis , Orthomyxoviridae/metabolismo , ARN Viral/biosíntesis , Factor de Necrosis Tumoral alfa/biosíntesis , Proteínas Virales/biosíntesis
18.
J Virol ; 75(13): 5921-9, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11390593

RESUMEN

Infection of humans with influenza A virus (IAV) results in a severe transient leukopenia. The goal of these studies was to analyze possible mechanisms behind this IAV-induced leukopenia with emphasis on the potential induction of apoptosis of lymphocytes by the virus. Analysis of lymphocyte subpopulations after exposure to IAV showed that a portion of CD3(+), CD4(+), CD8(+), and CD19(+) lymphocytes became apoptotic (terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling positive). The percentage of cells that are infected was shown to be less than the percentage of apoptotic cells, suggesting that direct effects of cell infection by the virus cannot account fully for the high level of cell death. Removal of monocytes-macrophages after IAV exposure reduced the percent of lymphocytes that were apoptotic. Treatment of virus-exposed cultures with anti-tumor necrosis factor alpha did not reduce the percentage of lymphocytes that were apoptotic. In virus-exposed cultures treated with anti-FasL antibody, recombinant soluble human Fas, Ac-DEVD-CHO (caspase-3 inhibitor), or Z-VAD-FMK (general caspase inhibitor), apoptosis and production of the active form of caspase-3 was reduced. The apoptotic cells were Fas-high-density cells while the nonapoptotic cells expressed a low density of Fas. The present studies showed that Fas-FasL signaling plays a major role in the induction of apoptosis in lymphocytes after exposure to IAV. Since the host response to influenza virus commonly results in recovery from the infection, with residual disease uncommon, lymphocyte apoptosis likely represents a part of an overall beneficial immune response but could be a possible mechanism of disease pathogenesis.


Asunto(s)
Apoptosis , Virus de la Influenza A/fisiología , Linfocitos/fisiología , Clorometilcetonas de Aminoácidos/farmacología , Proteína Ligando Fas , Humanos , Glicoproteínas de Membrana/análisis , Oligopéptidos/farmacología , Receptor fas/análisis
19.
Arch Virol ; 130(3-4): 441-55, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8517795

RESUMEN

The binding of influenza virus to the surface of cells and the internalization of virus particles by all or a subset of cells are key points in the pathogenesis of viral infection. The current studies established a method for discrimination of surface-bound from internalized influenza virus. Fluorescein isothiocyanate (FITC) was attached to the viral hemagglutinin and neuroaminidase proteins; the fluorescent virus retained infectivity. A flow cytometric technique was then adapted for study of virus-cell interactions, with addition of ethidium bromide to quench green fluorescence associated with FITC-labeled virus that was cell-bound but remained external. Ethidium bromide was excluded by intact cell membranes, and internalized virions retained green fluorescence. Cells could be examined by fluorescence microscopy or flow cytometry, with flow cytometry allowing rapid, kinetic assessment of large numbers of cells and subsets of virus-exposed cells. The data showed that, whereas a majority of both monocytes-macrophages and lymphocytes bound influenza virus, a large percentage of monocytes-macrophages but only a very small percentage of lymphocytes internalized the virus. This procedure provides a simple and effective method to distinguish surface-bound from internalized influenza virus, and allows precise kinetic analyses on large numbers of cells.


Asunto(s)
Virus de la Influenza A/fisiología , Linfocitos/microbiología , Macrófagos/microbiología , Monocitos/microbiología , Adulto , Etidio , Citometría de Flujo , Fluoresceína-5-Isotiocianato , Humanos , Técnicas In Vitro , Microscopía Fluorescente
20.
J Food Prot ; 43(7): 555-557, 1980 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30822956

RESUMEN

Effects of eight grinding methods on textural properties of cooked beef patties were tested on beef from two sources. The methods tested were representative of those used by processors throughout the country and the sources were U.S. Choice chucks and U.S. Utility grade triangles. Patties from the .32 × .32 cm and silent cutter methods scored highest for tenderness and were lowest in amounts of subjectively determined connective tissue for both Choice and Utility grade beef. Sensory panel and Instron means indicated that the size of plate for initial grind was related (P < .10) to tenderness and the amount of connective tissue in the final product. Patties prepared by the 2.54 × .32 cm grinding method were generally inferior to patties prepared by the .32 × .32 cm grinding method.

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