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1.
J Exp Med ; 180(4): 1541-6, 1994 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-7931086

RESUMEN

The mucosa of the gastrointestinal tract is presumably an important reservoir for human immunodeficiency virus type 1 (HIV-1), but the level of virus-expressing cells within the mucosa of infected patients is not known. To study this issue, we identified HIV-1 mRNA-expressing (positive) mononuclear cells by in situ hybridization in specimens of esophageal mucosa from eight patients with acquired immune deficiency syndrome (AIDS) and esophageal infections. Such cells were not found in four patients with AIDS and no esophageal disease. Immunocytochemical staining revealed that the mononuclear cells expressing HIV-1 mRNA were lamina propria macrophages. The prevalence of positive cells was measured by triplicate determinations in each of three experiments using an inverse sampling technique. No significant differences in prevalence were found among patients or among experiments. The overall prevalence of HIV-1 mRNA-expressing cells in the esophageal lamina propria was 0.059 +/- 0.01%. This prevalence of cells expressing HIV-1 mRNA in the mucosa of patients with mucosal infections may reflect the local abundance of stimuli such as bacterial endotoxin and certain cytokines capable of inducing viral transcription.


Asunto(s)
Esófago/microbiología , VIH-1/genética , ARN Mensajero/análisis , ARN Viral/análisis , Síndrome de Inmunodeficiencia Adquirida/microbiología , Esófago/citología , Humanos , Inmunohistoquímica , Hibridación in Situ , Membrana Mucosa/citología , Membrana Mucosa/microbiología
2.
J Exp Med ; 163(6): 1376-90, 1986 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-3086480

RESUMEN

The present study reports the surprising observation that IL-2-R+ cells can be detected in fresh, unstimulated, murine spleen T cells from unimmunized mice by flow cytometry using the monoclonal anti-receptor antibody 7D4. Also, unexpectedly, these cells were found exclusively in the L3T4+Lyt-2- population by two-color fluorescence, in contrast to receptor+ cells after stimulation, in which both L3T4+Lyt-2- and Lyt-2+L3T4- cells were found. The fraction of splenic T cells bearing IL-2-R reproducibly varies twofold under non-H-2-linked genetic control, with high expression in DBA/2 and BALB/c (approximately 6-7%) and low expression in B10.D2 and C57BL/6 (3%). This correlates quantitatively with a greater responsiveness of the DBA/2 and BALB/c splenic T cells to high doses of IL-2, compared with B10.D2 T cells; twice as many B10.D2 T cells as DBA/2 T cells were required to get the same response. Studies with 23 B X D RI strains revealed that the level of IL-2-R+ cells in unstimulated spleen cells was regulated by multiple genes, very likely including at least one gene on chromosome 7, near the HBB locus. The mapping makes novel use of nonparametric (Smirnov) statistics, which we suggest may be of general usefulness in similar analyses of RI strains.


Asunto(s)
Regulación de la Expresión Génica , Interleucina-2/farmacología , Receptores Inmunológicos/genética , Linfocitos T/metabolismo , Animales , Antígenos Ly/análisis , Ligamiento Genético , Inmunización , Ratones , Ratones Endogámicos , Receptores Inmunológicos/biosíntesis , Receptores de Interleucina-2 , Proteínas Recombinantes/farmacología , Bazo/citología , Linfocitos T/clasificación
3.
J Clin Invest ; 51(8): 2197-204, 1972 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-5054472

RESUMEN

Two grey collie dogs had regular cyclic fluctuations in the number of all formed elements of the blood. The period lengths for all elements for an individual dog were the same, but the pattern of fluctuation for each element was distinctive. Normal dogs lacked periodic fluctuations.The patterns of day-to-day variation in the normal dogs counts were consistent with a first-order autoregressive process of serial dependence (i.e., each observation of the series depends on the last preceding observation and no others). The grey collie counts showed the same pattern of serial dependence after the component of the over-all variability due to cyclic oscillation was removed. These data suggest that a defect of hematopoietic regulation at the stem cell level leads to periodic interruptions of production of all hematopoietic elements and accounts for the cycles seen in the peripheral blood counts.


Asunto(s)
Agranulocitosis/veterinaria , Enfermedades de los Perros/fisiopatología , Hematopoyesis , Neutrófilos , Agranulocitosis/sangre , Agranulocitosis/fisiopatología , Animales , Enfermedades de los Perros/sangre , Perros , Femenino , Células Madre Hematopoyéticas , Recuento de Leucocitos , Masculino , Periodicidad , Factores de Tiempo
4.
J Clin Invest ; 76(4): 1581-4, 1985 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3863835

RESUMEN

In families with X-linked chronic granulomatous disease (CGD), heterozygous females have two stable populations of polymorphonuclear leukocytes (PMN) in their blood; one normal, the other, deficient in oxygen metabolism. The two types of PMN can be distinguished by the ability or lack of ability to reduce nitroblue tetrazolium dye. The variation in the percent normal PMN among 11 CGD heterozygotes was shown to follow a binomial distribution based on eight independent trials and a chance of success of 50%. This is consistent with the occurrence of X-chromosome inactivation (lyonization) when eight embryonic founder cells for the hematopoietic system are present. Serial determinations of the percent normal PMN in individual heterozygotes showed very limited variability (standard deviations ranged from 2.0% to 5.2%) most of which could be ascribed to experimental error. An estimate of the remaining variation (residual variance) was introduced into a well-known formula to calculate the appropriate number of pluripotent stem cells necessary to support hematopoiesis and a figure exceeding 400 was obtained. Thus, the data indicate that in humans there is a highly polyclonal system of hematopoiesis.


Asunto(s)
Compensación de Dosificación (Genética) , Marcadores Genéticos , Enfermedad Granulomatosa Crónica/genética , Hematopoyesis , Neutrófilos/metabolismo , Células Clonales/patología , Femenino , Enfermedad Granulomatosa Crónica/patología , Células Madre Hematopoyéticas/patología , Heterocigoto , Humanos , Neutrófilos/clasificación , Nitroazul de Tetrazolio/metabolismo , Oxidación-Reducción , Oxígeno/metabolismo
5.
J Clin Invest ; 89(5): 1403-10, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1569183

RESUMEN

To explore the mechanisms of antigen-specific immune unresponsiveness seen in microfilaremic patients with bancroftian filariasis, T and B cell precursor frequency analysis was performed using PBMC from individuals with either asymptomatic microfilaremia (MF, n = 7) or chronic lymphatic obstruction (CP, n = 20). Highly purified CD3+ cells were partially reconstituted with adherent cells and their proliferative response to parasite antigens determined in cultures of T cells by limiting dilution analysis. A filter immunoplaque assay also assessed the frequency of both total and parasite-specific Ig-producing B cells. While the lymphocyte proliferation to mitogens and to a nonparasite antigen (Streptolysin-O, [SLO]) were similar in all groups of patients, the frequency of parasite-specific CD3+ T cells was significantly lower (geometric mean [GM], 1/3,757) in MF patients when compared to that in CP patients (GM 1/1,513; P less than 0.001). Similarly, the proportion of lymphocytes producing parasite-specific IgE or IgG was significantly lower in MF patients (IgE mean, 0.2%; IgG mean, 0.33%) compared with CP patients (IgE mean, 3.2%; IgG mean, 1.76%; P less than 0.05 for both comparisons). These observations imply that low numbers of parasite-specific T and B lymphocytes may be partially responsible for the severely diminished capacity of lymphocytes from patients with MF to produce parasite-specific antibody and to proliferate to parasite antigen in vitro. Such differences in parasite-specific lymphocyte responses suggest that tolerance by clonal anergy may be a critical mechanism for maintaining the microfilaremic state.


Asunto(s)
Linfocitos B/inmunología , Filariasis Linfática/inmunología , Linfocitos T/inmunología , Animales , Anticuerpos Antihelmínticos/inmunología , Antígenos Helmínticos/análisis , Brugia/inmunología , Humanos , Tolerancia Inmunológica , Inmunidad Celular , Inmunoglobulina E/inmunología , Inmunoglobulina G/inmunología , Activación de Linfocitos
6.
J Clin Oncol ; 7(7): 947-58, 1989 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2738625

RESUMEN

Cardiac toxicity was evaluated in 24 patients who received epirubicin as a single chemotherapeutic agent, in doses of either 30 mg/m2 every week (11 patients) or 90 mg/m2 every 3 weeks (13 patients). The total doses of epirubicin ranged from 180 mg/m2 to 918 mg/m2 (mean, 491 +/- 187). No patient had prior heart disease, hypertension, mediastinal irradiation, or chemotherapy with other anthracycline agents. None of the patients developed overt heart failure, significant arrhythmias, ECG alterations, or roentgenographic changes in heart size. There was no significant change in the mean value of echocardiographic percent fractional shortening before and after epirubicin therapy. Patients receiving epirubicin doses less than 450 mg/m2 had minimal hemodynamic disturbances; however, no cut-off point separating two significantly different subpopulations could be demonstrated. Endomyocardial biopsy was performed on all patients; 20 biopsies were evaluable. Histologic and ultrastructural changes were similar to those caused by other anthracycline agents. A strong correlation was demonstrated between total dose of epirubicin and pathologic change as quantified using the Billingham scale (r = .7, P = .0006). A cut-off point beyond which there was a probability of increased pathologic damage was statistically defined at 450 mg/m2 of epirubicin. Severe pathologic alterations and moderate hemodynamic changes were observed in only one patient, who received 918 mg/m2 of epirubicin. Patients who are expected to receive epirubicin in excess of 450 mg/m2 should be monitored for cardiac toxicity, and continuation of epirubicin therapy beyond 900 mg/m2 should be based on the results of monitoring.


Asunto(s)
Epirrubicina/efectos adversos , Cardiopatías/inducido químicamente , Adulto , Neoplasias de la Mama/tratamiento farmacológico , Epirrubicina/uso terapéutico , Femenino , Cardiopatías/patología , Cardiopatías/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico
7.
Endocrinology ; 119(5): 2193-200, 1986 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3021435

RESUMEN

3H-Labeled inositol phosphate accumulation is observed when prelabeled FRTL-5 cells (a rat thyroid cell line) are exposed to norepinephrine (NE) or TSH. The presence of inositol trisphosphate among the products implicates a phosphodiesterase-catalyzed hydrolysis of phosphatidylinositol 4,5-bisphosphate. The response to NE is much greater than that to TSH. This may be explained by the ability of cAMP to inhibit inositol phosphate accumulation in these cells. The stimulation by NE is inhibited by alpha 1-adrenergic receptor antagonists and is markedly potentiated in medium of reduced Ca2+ concentration. After chronic withdrawal of TSH from the growth medium, the magnitude of the response to NE is considerably reduced; however, there is no substantial shift in the dose-response curve. This reflects the dependency of alpha 1-adrenergic receptor expression on TSH in the FRTL-5 cell. In contrast, the characteristics of inositol phosphate accumulation induced by acute treatment with TSH are similar in cells maintained in the presence or absence of a low concentration of this hormone, and correlate well with the iodide efflux and iodination of thyroglobulin observed in response to TSH. These results support the hypothesis that TSH may mediate certain of its physiological effects through cAMP-independent mechanisms, such as phospholipid/Ca2+ and C-kinase pathways.


Asunto(s)
Fosfatos de Inositol/metabolismo , Norepinefrina/farmacología , Fosfatos de Azúcar/metabolismo , Glándula Tiroides/efectos de los fármacos , Tirotropina/farmacología , Animales , Bucladesina/farmacología , Línea Celular , Cloruros/farmacología , Litio/farmacología , Cloruro de Litio , Fentolamina/farmacología , Prazosina/farmacología , Propranolol/farmacología , Ratas , Glándula Tiroides/metabolismo , Factores de Tiempo , Factores de Virulencia de Bordetella/farmacología
8.
Am J Med ; 78(1): 9-14, 1985 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3917606

RESUMEN

Both antihistamines and cromolyn sodium have been suggested for the treatment of systemic mastocytosis. To determine if one drug regimen was superior to the other, eight patients with systemic mastocytosis were admitted to a double-blind, double-crossover study in which the therapeutic efficacy of cromolyn sodium was compared with that of a combination of chlorpheniramine and cimetidine. Response to therapy was assessed by the patients using symptom scores and by the attending physicians during clinic examinations in addition to sequential plasma and urinary histamine determinations. In the six patients who completed the trial, the patient symptom scores and the physician evaluations indicated that there was no advantage of one drug regimen over the other. Plasma and urinary histamine levels, markedly elevated in most of the patients, were not consistently altered by administration of either cromolyn sodium or the combined antihistamines. Thus, cromolyn sodium and the combined antihistamines were indistinguishable when used for the symptomatic treatment of systemic mastocytosis, and neither regimen altered systemic histamine levels.


Asunto(s)
Clorfeniramina/uso terapéutico , Cimetidina/uso terapéutico , Cromolin Sódico/uso terapéutico , Urticaria Pigmentosa/tratamiento farmacológico , Adulto , Anciano , Análisis de Varianza , Clorfeniramina/efectos adversos , Cimetidina/efectos adversos , Cromolin Sódico/efectos adversos , Método Doble Ciego , Evaluación de Medicamentos , Quimioterapia Combinada , Femenino , Histamina/sangre , Histamina/orina , Humanos , Masculino , Persona de Mediana Edad , Distribución Aleatoria
9.
Am J Med ; 70(3): 655-8, 1981 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7011019

RESUMEN

To evaluate the efficacy of daily cleansing of the urethral meatus-catheter junction in preventing bacteriuria during closed urinary drainage, randomized, controlled trials of two widely recommended regimens for meatal care were completed. In 32 (16.0 percent) of 200 patients given twice daily applications of a povidone-iodine solution and ointment bacteriuria was acquired, as compared with 24 (12.4 percent) of 194 patients not given this treatment. In 28 (12.2 percent) of 229 patients given once daily meatal cleansing with a nonantiseptic solution of green soap and water bacteriuria was acquired, as compared with 18 (8.1 percent) of 23 patients not given special meatal care. There was no evidence in either trial of a beneficial effect of meatal care. Moreover, each of four different statistical methods indicated that the rates of bacteriuria were higher in the treated groups than in the untreated groups. In subsets of female patients at high risk in both studies significantly higher rates of bacteriuria were noted in the treated groups than in the untreated groups. Current methods of meatal care appear to be hazardous, as well as expensive, and cannot be recommended as measures to control infection.


Asunto(s)
Cateterismo Urinario/efectos adversos , Infecciones Urinarias/prevención & control , Administración Tópica , Adulto , Bacteriuria/prevención & control , Ensayos Clínicos como Asunto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pomadas , Povidona Yodada/administración & dosificación , Jabones , Uretra/microbiología , Infecciones Urinarias/etiología
10.
Mol Biochem Parasitol ; 64(1): 55-63, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8078523

RESUMEN

Invasion of erythrocytes by malaria parasites involves multiple receptor-ligand interactions. To elucidate these pathways, we made use of four parasite clones with differing specificities for invasion, erythrocytes that are mutant for either glycophorin A or B, and enzyme modification of the erythrocyte surface with neuraminidase and trypsin. Neuraminidase alone abolishes invasion of two parasite clones (Dd2, FCR3/A2); these invade after trypsin treatment alone. A third clone (7G8) is unable to invade trypsin-treated erythrocytes. The fourth clone (HB3) can invade after either neuraminidase or trypsin treatment. The receptor for invasion of trypsin-treated erythrocytes was explored in two ways: treatment of trypsin-treated normal cells with neuraminidase, and trypsin treatment of glycophorin B-deficient cells. Both treatments eliminated invasion by all clones, indicating that the trypsin-independent pathway uses sialic acid and glycophorin B. To identify parasite proteins involved in the different pathways, erythrocyte binding assays were performed with soluble parasite proteins from each clone. Based on binding assays using erythrocytes that lack glycophorin A, the parasite protein known as EBA-175 appears to bind predominantly to glycophorin A. In contrast, the glycophorin B pathway does not appear to involve EBA-175, as binding of EBA-175 was similarly reduced to trypsin-treated normal and trypsin-treated glycophorin B-deficient erythrocytes. Thus, the glycophorin B-dependent, sialic acid-dependent invasion of trypsin-treated normal erythrocytes uses a different parasite ligand, indicating two or more sialic-dependent pathways for invasion. Clone 7G8, which cannot invade trypsin-treated erythrocytes, may be missing the ligand for invasion via glycophorin B.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Antígenos de Protozoos , Proteínas Portadoras , Membrana Eritrocítica/metabolismo , Eritrocitos/parasitología , Glicoforinas/metabolismo , Plasmodium falciparum/fisiología , Proteínas Protozoarias , Animales , Células Clonales , Membrana Eritrocítica/efectos de los fármacos , Glicoforinas/genética , Humanos , Ligandos , Malaria Falciparum/sangre , Malaria Falciparum/parasitología , Neuraminidasa/farmacología , Tripsina/farmacología
11.
AIDS Res Hum Retroviruses ; 11(2): 297-306, 1995 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7742043

RESUMEN

Rabbits can be infected with human immunodeficiency virus (HIV-1), but no disease signs similar to acquired immunodeficiency syndrome (AIDS) have been reported to date. In our attempt to develop types of HIV-1 more virulent for rabbits, an immunodeficiency characterized by CD4+ lymphocytopenia and opportunistic infection was induced by transfusion from HIV-1-infected rabbits. The original donor was infected for 27 months; initial passage resulted in infection of two rabbits. Transfusions from these two infected rabbits. Transfusions from these two infected rabbits caused immunodeficiency in 12 recipients. One rabbit died at 3 months and a second at 8 months postransfusion with lymphocyte depletion in lymphoid organs; one of these and another of the CD4+ lymphocytopenic rabbits had opportunistic infections. Lentivirus-like particles were detected in thymus and spleen from an affected rabbit. Despite appearance of AIDS-like disease signs, antibodies to HIV-1 probes were detected in rabbits receiving passaged blood. However, RNA transcripts hybridizing with HIV-1 probes were detected in organs of some rabbits, implicating the initial HIV infection in the disease. Transfusion from uninfected donors produced no signs of immunodeficiency, which suggests the involvement of an HIV-related agent. The present data do not allow definitive characterization of the agent(s) involved in the immunodeficiency. Possibilities include activation of a rabbit retrovirus or, alternatively, development of a mutated HIV-1 strain.


Asunto(s)
Sangre/virología , Linfocitos T CD4-Positivos/patología , Infecciones por VIH/transmisión , VIH-1/patogenicidad , Síndromes de Inmunodeficiencia/virología , Animales , Transfusión Sanguínea , Infecciones por VIH/inmunología , Infecciones por VIH/fisiopatología , VIH-1/inmunología , Humanos , Síndromes de Inmunodeficiencia/inmunología , Síndromes de Inmunodeficiencia/fisiopatología , Ganglios Linfáticos/virología , Microscopía Electrónica , ARN Viral/análisis , Conejos , Bazo/ultraestructura , Bazo/virología , Timo/ultraestructura , Timo/virología
12.
Inflamm Bowel Dis ; 1(3): 184-92, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-23282388

RESUMEN

: In this study the TCR-Vß repertoire expressed in T cells of lamina propria mononuclear cells (LPMC) and peripheral blood mononuclear cells (PBMC) was examined using a reverse transcription-PCR (RT-PCR) technique for TCR-Vß mRNA. Using a qualitative RT-PCR method, LPMC of patients with IBD and control individuals were shown to contain mRNA for each of 20 TCR-Vß families, indicating that IBD is not associated with a major deletion or expansion of any TCR-Vß family. Subsequently, using a quantitative method for four frequently expressed TCR-Vß families, it was shown that the pattern of TCR-Vß expression was different in PBMC and LPMC of both IBD patients and control individuals. In addition, it was shown that the LPMC/PBMC ratio of mean mRNA values for TCR-Vß2, but not for TCR-Vß6, 7, and 14 was lower in IBD patients than control individuals. These results show that the TCR-Vß repertoire in PBMC and LPMC is different both in IBD patients and control individuals. In addition, they show that the TCR-Vß repertoire is altered in IBD, possibly due to an immune response to disease specific antigens, superantigens or neoantigens.

13.
Am J Med Genet ; 10(1): 77-89, 1981.
Artículo en Inglés | MEDLINE | ID: mdl-7294063

RESUMEN

We present cytogenetic findings in 7 familial and 5 sporadic Alzheimer disease (AD) patients and 34 unaffected relatives, spouses, and normal controls. Our study was prompted by reports of increased chromosome abnormalities in patients and family members at risk for AD. Coded peripheral blood chromosome preparations were evaluated for aneuploidy, aberration rates, and banding patterns. Statistical analyses of our results showed no increase in aneuploidy or aberrations in AD patients, their relatives, or normals. Chromosome loss or gain in aneuploid cells was not specific except in two individuals. These two older persons studied, one with AD and one unaffected, were observed to have increased sex chromosome aneuploidy. This finding was attributed to aging and was not considered to be an effect of AD.


Asunto(s)
Enfermedad de Alzheimer/genética , Aneuploidia , Aberraciones Cromosómicas , Demencia/genética , Adulto , Anciano , Niño , Bandeo Cromosómico , Femenino , Heterocigoto , Humanos , Cariotipificación , Masculino , Persona de Mediana Edad , Aberraciones Cromosómicas Sexuales
14.
Infect Control Hosp Epidemiol ; 12(3): 157-62, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2022861

RESUMEN

OBJECTIVE: To determine the efficacy of meatal treatment with a polyantibiotic cream in the prevention of bacteriuria during transurethral bladder catheterization. DESIGN: Randomized controlled trial. SETTING: Community teaching hospital. PATIENTS: Adult patients who underwent closed urinary catheter drainage for short and intermediate durations (two to 30 days). INTERVENTION: Polyantibiotic cream containing polymyxin B sulfate, neomycin sulfate, and gramicidin was applied to the urethral meatus-catheter interface three times daily from the first day of catheterization until bacteriuria was found. The onset of bacteriuria was defined as the day the colonizing species first achieved a colony count of greater than or equal to 1000 colonies/ml. Patients randomized to the control group received routine meatal care with cleansing of the meatal surface during daily bathing. RESULTS: Among 2,923 patients who were randomly allocated to receive either the protocol meatal care or routine care, the evaluable study population consisted of 747 patients who were nonbacteriuric and who remained catheterized for more than two days. Overall, 26 (6.8%) of 383 patients given the polyantibiotic treatment acquired bacteriuria, as compared to 37 (10.1%) of 364 patients not given this treatment (p = .167). A Cox proportional hazards regression analysis showed that, among putative risk factors including lack of meatal care, only female gender, a meatal swab culture yielding gram-negative rods or enterococci, and lack of antibiotic use during catheterization were independently associated with the development of bacteriuria. CONCLUSIONS: The adverse effect of meatal care noted in earlier studies of a disinfectant ointment applied twice daily was not found in this study of an antimicrobial preparation in a cream vehicle applied three times daily. However, the results do not support meatal care as an efficacious method to prevent catheter-associated bacteriuria in all patients.


Asunto(s)
Antibacterianos , Bacteriuria/prevención & control , Quimioterapia Combinada/administración & dosificación , Uretra/microbiología , Cateterismo Urinario/efectos adversos , Anciano , Bacteriuria/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pomadas
15.
J Appl Physiol (1985) ; 70(5): 2155-63, 1991 May.
Artículo en Inglés | MEDLINE | ID: mdl-1864798

RESUMEN

The hemodynamic response to inhalation anesthesia is influenced by three factors: 1) the specific drug, 2) the dose, and 3) individual characteristics of the subject. To investigate the importance of these factors on the cardiovascular response, we administered five doses [0, 0.5, 1.0, 1.5, and 2.0 minimum alveolar concentration (MAC)] of enflurane, halothane, and isoflurane to each of six dogs. Twelve hemodynamic variables were measured. For all variables, a change in the dose of each drug produced a consistent effect in each dog. Increases in dose resulted in significant decreases in seven variables [left ventricular ejection fraction, cardiac index (CI), stroke volume index (SVI), mean arterial pressure (MAP), mean pulmonary arterial pressure (MPAP), left ventricular stroke work index (LVSWI), and heart rate (HR)] and a significant increase in one variable [central venous pressure (CVP)]. In contrast, the response of individual dogs to different drugs was not consistent. For seven variables [MAP, MPAP, LVSWI, CVP, pulmonary capillary wedge pressure (PCWP), end-diastolic volume index (EDVI), and end-systolic volume index (ESVI)], a significant difference in the responses of a dog to two drugs was greater than zero, whereas a significant difference in the response of at least one other dog to the same two drugs was less than zero (discordant dog-drug interactions). Thus, in contrast to the consistency of the cardiovascular response to changes in dose, the hemodynamic response to different drugs was inconsistent among dogs. We also studied the effect of fluid challenge on hemodynamic response at 1.5 or 2.0 MAC of the three drugs given to each dog.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Anestésicos/farmacología , Hemodinámica/efectos de los fármacos , Administración por Inhalación , Anestésicos/administración & dosificación , Animales , Presión Sanguínea/efectos de los fármacos , Perros , Relación Dosis-Respuesta a Droga , Enflurano/administración & dosificación , Enflurano/farmacología , Gases/sangre , Halotano/administración & dosificación , Halotano/farmacología , Frecuencia Cardíaca/efectos de los fármacos , Isoflurano/administración & dosificación , Isoflurano/farmacología , Masculino , Circulación Pulmonar/efectos de los fármacos , Volumen Sistólico/efectos de los fármacos
16.
Science ; 202(4372): 1105, 1978 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-715462
17.
J Virol Methods ; 79(1): 41-50, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10328534

RESUMEN

The tumorigenicity of adenovirus (Ad) 12-transformed mouse cells was evaluated by analyzing the relationship of tumor cell dose to tumor incidence and tumor latency. The tumor producing dose 50% endpoint values used to define these relationships remained stable during 52 weeks of serial passage in tissue culture and were not determined by low frequency events within the cell population. The data from these analyses suggest that the phenotype of Ad12-transformed mouse cells is influenced by two set of traits--those traits that determine the threshold number of cells required for tumor formation and those that extend the cell dose-dependent tumor latency period. Both traits are established independently of cell immortalization, and both can be influenced by the immunological status of tumor-challenged animals. These observations were verified by using mouse cells transformed by Ad5 and SV40. The biological and molecular processes that contribute to these traits remain to be determined. The approach developed by this analysis provides a reliable, quantitative means of evaluating endogenous traits that determine transformed cell tumorigenicity. This method can also be used to test the effects of tumor cell manipulations or changes in host response that could alter expression or detection of these neoplastic cell traits.


Asunto(s)
Adenoviridae/fisiología , Transformación Celular Neoplásica , Transformación Celular Viral/fisiología , Neoplasias Experimentales/virología , Virus 40 de los Simios/fisiología , Animales , Línea Celular Transformada , Trasplante de Células , Cricetinae , Estudios de Evaluación como Asunto , Ratones , Ratones Endogámicos BALB C , Fenotipo
18.
J Invest Surg ; 14(2): 109-20, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11396618

RESUMEN

Diminished tissue injury and shortened clinical recovery are benefits of using an endoscopic approach for patients needing operative procedure. In the course of developing an experimental model requiring procurement of topographically precise lung biopsy specimens, we sought to apply thoracoscopy as a research alternative to thoracotomy. In addition, we investigated the influence of thoracoscopy on postprocedure recovery practices using rabbits divided into four treatment groups. Rabbit groups 1 and 2 underwent thoracoscopy and lung biopsy while maintained by one-lung anesthesia. Additionally, group 2 had ketoprofen and bupivacaine HCl analgesics injected for treatment during postprocedure recovery. These two groups were compared to control rabbits in groups 3 and 4, which underwent inhalant anesthesia without thoracoscopy. Control group 3 also received the injection analgesic combination. During recovery, rabbit behavior was systematically assessed for evidence of pain. No behavior considered indicative of pain needing intervention was observed regardless of treatment group. Limited changes in plasma corticosterone, catecholamines, and prostaglandin E2 levels measured during recovery were difficult to associate with any treatment. Unexpectedly, significantly different mean corticosterone and catecholamines levels were detected in rabbits given the injection analgesic combination in the absence of thoracoscopic procedure, as compared to other treatment groups. The results highlight the importance of awareness that analgesic drug administration has the potential to alter homeostasis and affect interpretation of some study findings by its own guise. Correlation of the mean pain study results with plasma biochemical data supports preferential use of thoracoscopy as a refinement for limiting postprocedural pain in research models.


Asunto(s)
Pulmón/cirugía , Dolor Postoperatorio/prevención & control , Toracoscopía , Anestesia por Inhalación/métodos , Bienestar del Animal , Animales , Antiinflamatorios no Esteroideos/farmacología , Conducta Animal , Biopsia/métodos , Análisis de los Gases de la Sangre , Broncoscopía , Corticosterona/sangre , Dinoprostona/sangre , Modelos Animales de Enfermedad , Femenino , Pulmón/patología , Masculino , Norepinefrina/sangre , Conejos , Organismos Libres de Patógenos Específicos
20.
Biophys J ; 9(3): 347-59, 1969 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-5780713

RESUMEN

A unified mathematical model is presented of the reversible effects of ultraviolet (UV) and photoreactivating (PR) light on the chloroplast-forming ability of dark-grown Euglena gracilis (var. bacillaris). This model is an extension of several aspects of target theory and also of a model for the decay of photoreactivability in Euglena proposed by Schiff et al. The data presented in several earlier papers are compared with the predictions of the proposed unified model and reasonably good agreement is found.


Asunto(s)
Euglena/efectos de la radiación , Luz , Efectos de la Radiación , Rayos Ultravioleta , Adaptación Fisiológica , Animales , Cloroplastos/efectos de la radiación , Cinética , Matemática , Modelos Biológicos , Modelos Teóricos
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