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1.
Lab Anim ; 43(2): 182-90, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19246505

RESUMEN

The manner in which an animal's environment is furnished may have significant implications for animal welfare as well as research outcomes. We evaluated four different housing conditions to determine the effects of what has been considered standard rodent enrichment and the exercise opportunities those environments allow on disease progression in the amyotrophic lateral sclerosis mouse model. Forty-eight copper/zinc superoxide dismutase mice (strain: B6SJL-TgN [SOD1-G931]1Gur) (SOD1) and 48 control (C) (strain: B6SJL-TgN[SOD1]2Gur) male mice were randomly assigned to four different conditions where 12 SOD1 and 12 C animals were allotted to each condition (n = 96). Conditions tested the effects of standard housing, a forced exercise regime, access to a mouse house and opportunity for ad libitum exercise on a running wheel. In addition to the daily all-occurrence behavioural sampling, mice were weighed and tested twice per week on gait and Rotor-Rod performance until the mice reached the age of 150 days (C) or met the criteria for our humane endpoint (SOD1). The SOD1 mice exposed to the forced exercise regime and wheel access did better in average lifespan and Rotor-Rod performance, than SOD1 mice exposed to the standard cage and mouse house conditions. In SOD1 mice, stride length remained longest throughout the progression of the disease in mice exposed to the forced exercise regime compared with other SOD1 conditions. Within the control group, mice in the standard cage and forced exercise regime conditions performed significantly less than the mice with the mouse house and wheels on the Rotor-Rod. Alpha motor neuron counts were highest in mice with wheels and in mice exposed to forced exercise regime in both mouse strains. All SOD1 mice had significantly lower alpha neuron counts than controls (P < 0.05). These data show that different enrichment strategies affect behaviour and disease progression in a transgenic mouse model, and may have implications for the effects of these strategies on experimental outcomes.


Asunto(s)
Esclerosis Amiotrófica Lateral/fisiopatología , Vivienda para Animales , Condicionamiento Físico Animal/fisiología , Esclerosis Amiotrófica Lateral/patología , Animales , Conducta Animal/fisiología , Modelos Animales de Enfermedad , Marcha/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Neuronas Motoras/fisiología , Distribución Aleatoria , Médula Espinal/patología
2.
Scand J Med Sci Sports ; 18(4): 427-35, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18067512

RESUMEN

Expansion of the extracellular matrix is a prominent but poorly characterized feature of tendinosis. The present study aimed to characterize the extent and distribution of the large aggregating proteoglycan versican in patients with patellar tendinosis. We obtained tendon from tendinopathy patients undergoing debridement of the patellar tendon and from controls undergoing intramedullary tibial nailing. Versican content was investigated by Western blotting and immunohistochemistry. Microvessel thickness and density were determined using computer-assisted image analysis. Markers for smooth muscle actin, endothelial cells (CD31) and proliferating cells (Ki67) were examined immunohistochemically. Western blot analysis and immunohistochemical staining revealed elevated versican content in the proximal patellar tendon of tendinosis patients (P=0.042). Versican content was enriched in regions of fibrocartilage metaplasia and fibroblast proliferation, as well as in the perivascular matrix of proliferating microvessels and within the media and intima of arterioles. Microvessel density was higher in tendinosis tissue compared with control tissue. Versican deposition is a prominent feature of patellar tendinosis. Because this molecule is not only a component of normal fibrocartilagenous matrices but also implicated in a variety of soft tissue pathologies, future studies should further detail both pathological and adaptive roles of versican in tendons.


Asunto(s)
Traumatismos en Atletas/metabolismo , Traumatismos de la Rodilla/metabolismo , Ligamento Rotuliano/metabolismo , Tendinopatía/metabolismo , Versicanos/metabolismo , Adulto , Traumatismos en Atletas/patología , Biopsia , Western Blotting , Estudios de Casos y Controles , Matriz Extracelular/metabolismo , Femenino , Humanos , Inmunohistoquímica , Traumatismos de la Rodilla/patología , Masculino , Ligamento Rotuliano/patología , Tendinopatía/patología
3.
Am J Psychiatry ; 135(8): 936-9, 1978 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-665837

RESUMEN

The author treated 12 patients who had demonstrated only a minimal response to psychiatric treatment alone for their obesity with a combination of psychotherapy and an anorectic, phentermine resin. Psychotherapy was directed toward developing an awareness of the underlying anxiety related to the problem of obesity and fostering the subsequent ability to change the pattern of overeating. All 12 patients were treated successfully, and 9 reached ideal weight. Weight loss was maintained or additional weight was lost when the medication was discontinued.


Asunto(s)
Obesidad/terapia , Fentermina/uso terapéutico , Psicoterapia , Adolescente , Adulto , Actitud Frente a la Salud , Imagen Corporal , Peso Corporal , Estudios de Evaluación como Asunto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Obesidad/tratamiento farmacológico , Obesidad/psicología , Remisión Espontánea
4.
J Acquir Immune Defic Syndr (1988) ; 6(12): 1353-7, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7504724

RESUMEN

A Peruvian female prostitute population was evaluated over a 3-year period to determine the incidence and risk factors of retroviral and viral hepatitis transmission. At three survey periods, a questionnaire was administered and serum samples were obtained. A total of 966 subjects were studied, with 34% followed for 38 months, 22% followed for 18 months, and 44% evaluated just once. On initial evaluation, 3 (0.3%) had HIV-1 antibody, 170 (17.6%) had HTLV-I antibody, 578 (59.8%) had anti-HBc, and 7 (0.7%) had antibody to hepatitis C virus. The mean annual incidence of HTLV-I and hepatitis B infection was 1.6% and 4.7%, respectively. Univariate and logistic regression analysis of prevalence data indicated an association between sexual activity and HTLV-I and hepatitis B infection, but no independent risk factors were identified in cohort analysis. Parenteral risk factors were not associated with transmission, except for a small percentage of subjects who may have acquired hepatitis B infection from blood transfusions. These findings suggest that there is a high incidence of HTLV-I and hepatitis B infection from heterosexual contact in this female prostitute population.


Asunto(s)
Infecciones por HTLV-I/epidemiología , Hepatitis B/epidemiología , Hepatitis C/epidemiología , Hepatitis Viral Humana/epidemiología , Trabajo Sexual , Adulto , Femenino , Anticuerpos Anti-VIH/sangre , VIH-1/inmunología , Anticuerpos Anti-HTLV-I/sangre , Infecciones por HTLV-I/transmisión , Hepacivirus/inmunología , Anticuerpos Antihepatitis/sangre , Hepatitis B/transmisión , Anticuerpos contra la Hepatitis B/sangre , Hepatitis C/transmisión , Anticuerpos contra la Hepatitis C , Hepatitis Viral Humana/transmisión , Humanos , Incidencia , Persona de Mediana Edad , Perú/epidemiología , Prevalencia , Modelos de Riesgos Proporcionales , Análisis de Regresión , Factores de Riesgo , Conducta Sexual , Parejas Sexuales , Reacción a la Transfusión
5.
Artículo en Inglés | MEDLINE | ID: mdl-1560340

RESUMEN

Geographic variation in the HIV-1 virus is extensive but incompletely documented. We herein report the first genetic characterization of HIV-1 isolates from Zambia. The genomic region encoding the GAG polyprotein has been compared among 22 Zambian isolates and 14 North American isolates using a combination of polymerase chain reaction (PCR) and DNA sequencing methods. The Zambian isolates were similar to one another but distinct from other HIV-1 isolates. They exhibited a characteristic PCR "fingerprint" wherein certain primer combinations were unable to amplify because of mispairing. The sequence of the complete gag gene of three isolates from Zambia has been determined, and phylogenetic tree analysis placed them in a branch distinct from other African isolates and North American isolates. The PCR procedure used here may be widely applicable for genetic characterization of HIV-1.


Asunto(s)
VIH-1/genética , Filogenia , Secuencia de Bases , Sondas de ADN , Genes gag , Variación Genética , VIH-1/química , VIH-1/aislamiento & purificación , Humanos , Datos de Secuencia Molecular , América del Norte , Sondas de Oligonucleótidos , Reacción en Cadena de la Polimerasa , Zambia
6.
J Acquir Immune Defic Syndr (1988) ; 6(2): 115-9, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8433277

RESUMEN

Six commercial rapid test kits for HIV-1 antibody were evaluated. Four laboratory technologists tested sera from four groups of U.S. military personnel or dependents: 202 subjects positive for HIV-1 antibody by Western blot, 200 seronegative voluntary blood donors, 199 seronegative obstetrics/gynecology patients, and 99 subjects with sera reactive by ELISA but negative by recombinant protein EIA and indeterminate by Western blot. The three tests using solid-phase immunoassay technology demonstrated the highest mean sensitivity (> 99%) and specificity (> 91%) for all groups tested, including sera indeterminate by Western blot. Two dot-immunoblot assays were less specific, possibly due to indistinct reaction end points, and a latex agglutination assay was also less specific because of difficulty distinguishing reactive results from the granular background. In an "ease-of-use" assessment, solid-phase capture immunoassays required less time and equipment and were easier to interpret than other testing methods. Solid-phase capture immunoassays for HIV-1 antibody may be suitable for use in emergency situations and in developing countries because they are highly sensitive and specific and are rapidly performed with minimal laboratory equipment.


Asunto(s)
Serodiagnóstico del SIDA/métodos , Anticuerpos Anti-VIH/sangre , VIH-1/inmunología , Western Blotting , Ensayo de Inmunoadsorción Enzimática , Estudios de Evaluación como Asunto , Femenino , Humanos , Inmunoensayo/métodos , Pruebas de Fijación de Látex , Masculino , Juego de Reactivos para Diagnóstico , Sensibilidad y Especificidad
7.
Artículo en Inglés | MEDLINE | ID: mdl-1381438

RESUMEN

Human immunodeficiency virus type 1 (HIV-1) was isolated from five patients with late-stage disease treated with zidovudine (ZDV) for more than 1 year. Peripheral blood mononuclear cells (PBMCs) were used for all virus isolations and to assay for drug resistance. The isolates exhibited a 10- to 100-fold decrease in ZDV susceptibility compared to pretreatment isolates. Multiple clones of a 618 bp segment of the HIV reverse transcriptase gene encompassing codons 60-250 were sequenced for each isolate. The association of alterations at codons Asp67----Asn, Lys70----Arg, Thr215----Phe or Tyr, and Lys219----Gln with ZDV resistance has been previously noted (ref. 5). In this study, the most frequent alterations was Thr215----Tyr although genotypic mixtures of Thr/Tyr and Phe/Tyr were also observed. One isolate with a Tyr215 alteration and unaltered codons at 67, 70, and 219 had high-level ZDV resistance. Alterations at codons 67, 70, and 219 did not appear to increase resistance when seen in combination with Tyr215. Virus isolates obtained from each patient by cultivation with either 0 or 4 microM ZDV were compared and found to have similar alterations at codons 67, 70, 215, and 219, although one instance of apparent in vitro selection for Tyr215 over Phe215 was observed. Assays using PBMCs for virus propagation will permit susceptibility testing of HIV isolates from most patients on antiretroviral drugs to investigate the clinical significance of drug resistance.


Asunto(s)
Infecciones por VIH/microbiología , VIH-1/efectos de los fármacos , Zidovudina/uso terapéutico , Secuencia de Aminoácidos , Secuencia de Bases , Células Cultivadas , ADN Viral , Farmacorresistencia Microbiana/genética , Variación Genética , Genotipo , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/genética , Transcriptasa Inversa del VIH , VIH-1/enzimología , VIH-1/genética , VIH-1/aislamiento & purificación , Humanos , Pruebas de Sensibilidad Microbiana/métodos , Datos de Secuencia Molecular , Monocitos/microbiología , Fenotipo , ADN Polimerasa Dirigida por ARN/genética , Homología de Secuencia de Ácido Nucleico
8.
Virus Res ; 29(1): 59-70, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8105609

RESUMEN

Eighteen long-term T-cell lines were established from peripheral blood mononuclear cells of individuals infected with human T-lymphotropic virus type I (HTLV-I) or II (HTLV-II). These cell lines (10 HTLV-I and 8 HTLV-II), representing diverse pathologic profiles and geographic regions, have been in culture for over 6 months and have constitutively produced p24gag antigen. Antigenic characterization of the cell lines by Western blot analysis demonstrated that all but one produced gag (p24) and env (gp46 or gp52) structural proteins; one HTLV-I-infected cell line exhibited an aberrant protein profile. Phenotypic analysis of the HTLV-infected cell lines demonstrated phenotypes consistent with activated T-cells (CD5+, CD25+, HLA-DR+). The HTLV-I-infected cell lines were predominantly CD4+ (IR, FS, A212, SP, 1657, 1742, 3669, 1996, and 3614), whereas EG was CD8+. The HTLV-II-infected cell lines were either CD4+ (H2A, Y17, G12.1), CD8+ (H1H, H2E, Y03, Y06), or both (H1B). Restriction map analysis and subtyping of the viral genomes demonstrated heterogeneity among these isolates. Of the HTLV-I-infected cell lines, six were subtype II, one was subtype III and, on the basis of additional restriction sites, another subtype, tentatively classified as subtype IV, could be identified for three of the HTLV-I-infected cell lines. Of the HTLV-II-infected cell lines, six were subtype HTLV-IIa and two were subtype HTLV-IIb. While the majority of the cell lines resemble the prototypic HTLV-I-infected (MT-2) and HTLV-II-infected (MoT) cell lines, the antigenic, phenotypic, and genotypic data collectively demonstrate heterogeneity among viral isolates representing diverse geographic regions.


Asunto(s)
Línea Celular/microbiología , Virus Linfotrópico T Tipo 1 Humano/crecimiento & desarrollo , Virus Linfotrópico T Tipo 2 Humano/crecimiento & desarrollo , Linfocitos T/microbiología , Adulto , Secuencia de Bases , Niño , Antígenos de Deltaretrovirus/análisis , Demografía , Femenino , Variación Genética , Genoma Viral , Genotipo , Virus Linfotrópico T Tipo 1 Humano/genética , Virus Linfotrópico T Tipo 1 Humano/inmunología , Virus Linfotrópico T Tipo 2 Humano/genética , Virus Linfotrópico T Tipo 2 Humano/inmunología , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Fenotipo , Polimorfismo de Longitud del Fragmento de Restricción , Mapeo Restrictivo
9.
Biochem Pharmacol ; 46(9): 1601-6, 1993 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-8240417

RESUMEN

The kinetics of phosphoinositol 4,5 bisphosphate hydrolysis products in activated Plasmodium falciparum gametocytes suggests a role for inositol trisphosphate [Ins(1,4,5)P3] and diacylglycerol (DAG) in the signal transduction pathway of malaria gametocytes. To investigate further this role, compounds that have an effect on the metabolism and biologic functions of these second messengers were tested in an in vitro system. Gentamycin, 2,3 diphosphoglycerate (2,3 DPG) and magnesium ion (Mg2+), inhibitors of Ins(1,4,5)P3 5' phosphatase, all stimulated gametocytes to exflagellate in suspended animation buffer, pH 7.4, at room temperature. In addition, methylxanthines, caffeine and theobromine, calcium ionophore (A-23187), and external calcium also stimulated exflagellation. In contrast, neomycin, an aminoglycoside that inhibits phospholipase C activity, and heparin, an antagonist of Ins(1,4,5)P3 binding to its receptor, inhibited microgamete formation. Quinine and chloroquine which can inhibit both phospholipase A and C activity also inhibited gametocyte exflagellation. The consistent manner in which these various compounds affect gametocyte activation further implicates phosphoinositol turnover in the signal transduction pathway of falciparum gametocytes.


Asunto(s)
Fosfatidilinositoles/metabolismo , Plasmodium falciparum/fisiología , 2,3-Difosfoglicerato , Animales , Cafeína/farmacología , Calcio/metabolismo , Diglicéridos/metabolismo , Ácidos Difosfoglicéricos/farmacología , Gentamicinas/farmacología , Inositol Polifosfato 5-Fosfatasas , Magnesio/farmacología , Malaria/prevención & control , Malaria/transmisión , Monoéster Fosfórico Hidrolasas/antagonistas & inhibidores , Plasmodium falciparum/efectos de los fármacos , Plasmodium falciparum/metabolismo , Transducción de Señal , Teobromina/farmacología , Xantinas/farmacología
10.
Hum Pathol ; 11(5): 449-57, 1980 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7429491

RESUMEN

This report concerns the finding of round to ovoid electron dense, membrane bound structures 100 to 300 nm. in average diameter in four non-Hodgkin lymphoma cases studied ultrastructurally. In three of the cases the material for electron microscopy was obtained from lymph nodes. Two of the lymph nodes were replaced by nodular, poorly to moderately differentiated lymphocytic lymphoma, and the third was effaced by a diffuse histiocytic lymphoma. In the fourth case the specimen examined consisted of a spleen also replaced by nodular, poorly differentiate lymphocytic lymphoma. All cases appear to be primary abdominal lymphomas. The structures identified in the four lymphomas were similar in appearance to membrane bound neurosecretory granules when viewed by electron microscopy. It is proposed that the electron dense particles may represent peculiar lysosomes. Further cytochemical examination is needed to adequately characterize them. Although the presence of typical lysosomal granules in normal lymphocytes is a well known finding, we have not seen the type of granules described here i normal lymphocytes. Owing to the frequent use of electron microscopy examination to differentiate small cell undifferentiated (oat cell) carcinomas and, occasionally, other neuroendocrine neoplasms from lymphomas, the finding of these neurosecretory-like structures in lymphomas creates significant difficulty in the differential diagnosis and separation of these neoplasms by ultrastructural analysis.


Asunto(s)
Gránulos Citoplasmáticos/ultraestructura , Linfoma/metabolismo , Adulto , Anciano , Diagnóstico Diferencial , Femenino , Humanos , Neoplasias Pulmonares/diagnóstico , Linfoma/diagnóstico , Linfoma/ultraestructura , Lisosomas , Masculino , Persona de Mediana Edad
11.
J Heart Lung Transplant ; 15(12): 1223-32, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8981208

RESUMEN

BACKGROUND: Transplant arteriopathy (TA) is characterized by vessel wall thickening with prominent glycosaminoglycan and lipid deposits. In this light, we have recently demonstrated the distribution of proteoglycans in allograft coronary arteries. The aim of this study is to examine the distribution of apolipoproteins within allograft coronary arteries and to investigate their localization in relation to proteoglycans. METHOD: Particular transverse sections of left and right epicardial coronary arteries from 46 human cardiac allografts, 11 normal hearts, and 11 hearts with native atherosclerosis were stained immunohistochemically for apolipoprotein B, apolipoprotein (a) (apo[a]), apolipoprotein E (apoE), biglycan, decorin, and versican by use of an automated immunostainer. RESULTS: Apo(a) and apoE immunopositivity in TA was much more intense than that in native atherosclerosis, whereas the reverse was true for apoB. Prominent apoE deposits were evident circumferentially in endothelia and extracellularly in superficial intima of mildly diseased TA, as well as in deeper intima of severely diseased TA. Apo(a) had a staining pattern very similar to apoE except for a patchy deposition also seen in TA media. The intimal areas staining prominently with apoE or apo(a) in TA arteries corresponded very closely to the areas with proteoglycan deposits, especially versican. CONCLUSION: The distinctive patterns of apolipoprotein accumulation in TA and native atherosclefosis appear to reflect different pathogenetic processes in the two conditions. The colocalization of proteoglycans and apolipoproteins in TA intima supports the hypothesis that interactions between proteoglycans and apolipoproteins influence lipid retention and overload in allograft coronary arteries.


Asunto(s)
Apolipoproteínas B/análisis , Apolipoproteínas E/análisis , Apolipoproteínas/análisis , Vasos Coronarios/química , Trasplante de Corazón , Lipoproteína(a) , Proteoglicanos/análisis , Apoproteína(a) , Enfermedad de la Arteria Coronaria/metabolismo , Femenino , Humanos , Masculino , Túnica Íntima/química
12.
J Heart Lung Transplant ; 15(12): 1233-47, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8981209

RESUMEN

BACKGROUND: Histochemical staining has demonstrated previously dramatic deposits of glycosaminoglycans associated with prominent lipid accumulations in thickened vessel walls of allograft coronary arteries. In this study, we characterized the amount, distribution, and types of proteoglycan in the walls of coronary arteries from human cardiac allografts and from native atherosclerotic (NA) controls as part of a strategy to understand the pathogenesis of transplant arteriopathy (TA). METHOD: We used polyclonal rabbit antibodies against human biglycan, decorin, and versican localize the proteoglycan molecules in standardized transverse sections of the proximal left anterior descending and right coronary arteries. Slides were scored in a blinded fashion for intensity of proteoglycan staining (0 to 6+) and for localization in the vessel walls. RESULTS: Unique patterns of proteoglycan distribution were present in TA and NA. Biglycan was particularly prominent in intima and evolving atheromata in severely diseased TA coronary arteries, but not in NA. Decorin was present mainly in adventitia of all vessels and in the intima of NA. Prominent versican accumulation occurred in intima and media of TA coronaries, associated with smooth muscle cells and foam cells. There was a reciprocal pattern of biglycan and decorin staining. Versican colocalized with biglycan. Intimal biglycan and versican deposits were positively correlated to the extent of luminal narrowing in TA. CONCLUSION: The distinctive staining patterns for biglycan, decorin and versican in both native and allograft disease indicate that the synthesis and distribution of these proteoglycans are regulated by different local mechanisms in different atheromatous diseases.


Asunto(s)
Proteoglicanos Tipo Condroitín Sulfato/análisis , Enfermedad de la Arteria Coronaria/metabolismo , Enfermedad Coronaria/metabolismo , Vasos Coronarios/química , Trasplante de Corazón , Proteoglicanos/análisis , Biglicano , Decorina , Proteínas de la Matriz Extracelular , Femenino , Humanos , Inmunohistoquímica , Lectinas Tipo C , Masculino , Trasplante Homólogo , Túnica Íntima/química , Versicanos
13.
J Appl Physiol (1985) ; 72(1): 219-25, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1537717

RESUMEN

Biomechanical changes in airway cartilage could influence the mechanics of maximal expiratory flow and cough and the degree of shortening of activated airway smooth muscle. We examined the tensile stiffness of small samples of human tracheal cartilage rings in specimens obtained at autopsy from 10 individuals who ranged in age from 17 to 81 yr. The tensile properties of the cartilage were compared with its content of water (%water), glycosaminoglycans (chondroitin sulfate equivalents, mg/mg dry wt), and hydroxyproline content (mg hydroxyproline/mg dry weight). The average values for tensile stiffness ranged between 1 and 15 MPa and increased significantly with increasing age [tensile stiffness = 0.19 x (age in yr) + 2.02; r = 0.83, P less than 0.05]. The outermost layer of cartilage was the most stiff in all individuals, and the deeper layers were progressively less stiff. Water content and hydroxyproline content both decreased with increasing age. Thus tensile stiffness correlated inversely with water content and hydroxyproline content [tensile stiffness = -0.83 x (%water) + 16.4; r = 0.82, P less than .05 and tensile stiffness = -342 x (hydroxyproline content) + 25; r = 0.87, P less than 0.05]. Total tissue content of glycosaminoglycans did not change with age, although changes in glycosaminoglycan type and proteoglycan structure with increasing age have been described. We conclude that there are age-related changes in the biomechanical properties and biochemical composition of airway cartilage that could influence airway dynamics.


Asunto(s)
Cartílago/fisiología , Mecánica Respiratoria/fisiología , Tráquea/fisiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Envejecimiento/fisiología , Fenómenos Biomecánicos , Agua Corporal/metabolismo , Femenino , Glicosaminoglicanos/metabolismo , Humanos , Hidroxiprolina/metabolismo , Técnicas In Vitro , Masculino , Persona de Mediana Edad , Resistencia a la Tracción
14.
Am J Trop Med Hyg ; 45(6): 653-9, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1763791

RESUMEN

A seroepidemiologic survey was conducted to determine the prevalence of human immunodeficiency virus type 1 (HIV-1), HIV-2, human T cell lymphotropic virus type I (HTLV-I), and Treponema pallidum infection among southern Somalis. Sera were collected from 1,269 study subjects in the urban area of the capital city, Mogadishu, and in the rural towns of Merka, Qoryoley, and Kismayo. The subjects included 57 prostitutes, 79 sexually transmitted disease (STD) patients, and 1,133 others, including outpatient and hospitalized patients with leprosy, tuberculosis, other infectious diseases, individuals from rehabilitation camps and secondary schools, and Ethiopian immigrants. Results indicated that none of the sera were positive for HIV-1 and HIV-2 by Western blot, but one was positive for HTLV-I. The prostitutes had a significantly higher prevalence of treponemal antibody (50.8%; P less than 0.0001) than either the STD patients (12.6%) or the other subjects (5.2%). Epidemiologic data indicated that 94% of the males and females were circumcised and only 2.6% of the males used condoms. Overall, the results of this study suggested a very low prevalence of HIV-1, HIV-2, and HTLV-I infections, especially among prostitutes and STD patients, who were considered at greatest risk of contracting these retroviral infections.


Asunto(s)
Infecciones por VIH/epidemiología , VIH-1 , VIH-2 , Infecciones por HTLV-I/epidemiología , Adolescente , Adulto , Femenino , Infecciones por VIH/microbiología , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Seroepidemiológicos , Enfermedades de Transmisión Sexual/epidemiología , Somalia/epidemiología
15.
Am J Trop Med Hyg ; 43(1): 31-43, 1990 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2382763

RESUMEN

The extrinsic development of Leishmania major was observed in 2 man-biting sand flies, Phlebotomus duboscqi, a known vector, and Sergentomyia schwetzi, an assumed non-vector. Flies fed on a leishmanial lesion on the nose of a hamster were examined for infection at 0, 6, 12, 18, 24, 36, 48, and 60 hr and at approximately 24 hr intervals from day 3 to day 14 post-feeding. Infection rates, determined by light microscopy, were 47% (n = 258) in P. duboscqi and 5% (n = 162) in S. schwetzi. Transformation from amastigotes to "procyclic" promastigotes occurred in both species at 6-18 hr post-feeding. In P. duboscqi, the parasites multiplied rapidly and developed through as many as 10 forms, including at least 3 dividing-promastigote forms. Metacyclic promastigotes, the "infective" form, appeared at 6 days post-feeding, first in the region of the stomodeal valve, then in the pharynx, cibarium, and proboscis. In a single attempt 14 days post-feeding, a P. duboscqi transmitted L. major to a mouse by bite. In contrast, the parasites multiplied slowly in S. schwetzi, and did not develop beyond "procyclic" promastigotes. The parasites did not migrate anteriorly nor survive beyond 90 hr post-feeding, indicating that S. schwetzi is not a vector of L. major. Classical strategies for vector incrimination may be confounded by the isolation of non-infective early developmental forms of Leishmania from wild-caught non-vectors.


Asunto(s)
Insectos Vectores/parasitología , Leishmania tropica/crecimiento & desarrollo , Phlebotomus/parasitología , Psychodidae/parasitología , Animales , Femenino , Interacciones Huésped-Parásitos
16.
Am J Trop Med Hyg ; 45(3): 290-6, 1991 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1928563

RESUMEN

Leishmania isolates aspirated a few months apart from the spleen of an indigenous adult male kala-azar patient from Baringo District, Kenya, were biochemically characterized and compared. The patient lived within a dual focus of L. donovani kalazar and L. major cutaneous leishmaniasis. A primary Leishmania isolate from splenic aspirates was cryopreserved (NLB-294). The patient was treated with sodium stibogluconate for kala-azar and discharged. Three months later, he had clinical relapse and returned for retreatment. During his second visit, the patient participated in a diagnostic study in which urine and nasopharyngeal samples were cultured for leishmaniasis. Urine, nasopharyngeal, and splenic samples were positive for Leishmania. Secondary isolates from splenic (NLB-294-I) and urine (NLB-318) cultures were cryopreserved and characterized by cellulose acetate electrophoresis (CAE) using 20 enzymes. Whereas the urine isolate was typed as L. donovani, the splenic aspirate culture revealed a mixed infection with L. donovani and L. major. The primary isolate (NLB-294) was then characterized and also showed a mixed infection. To exclude the possibility of protein post-translational modifications in electrophoretic assays, the primary and secondary isolates were grown and processed under identical cultural and lysis conditions, and compared using CAE. The results were identical to the first electrophoretic assays showing mixed promastigote banding patterns. Stationary-phase promastigotes of the secondary splenic isolate (NLB-294-I) inoculated subcutaneously, intraperitoneally, and intracardially into Syrian hamsters and BALB/c mice produced both kala-azar and cutaneous leishmaniasis within 6.5 months.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Leishmania donovani/aislamiento & purificación , Leishmania tropica/aislamiento & purificación , Leishmaniasis Cutánea/complicaciones , Leishmaniasis Visceral/complicaciones , Adolescente , Animales , Cricetinae , Electroforesis en Acetato de Celulosa , Estudios de Seguimiento , Humanos , Isoenzimas/análisis , Kenia , Leishmania donovani/clasificación , Leishmania donovani/enzimología , Leishmania tropica/clasificación , Leishmania tropica/enzimología , Leishmaniasis Cutánea/parasitología , Leishmaniasis Visceral/parasitología , Masculino , Mesocricetus , Ratones , Ratones Endogámicos BALB C , Bazo/parasitología
17.
Am J Trop Med Hyg ; 49(1): 25-9, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8352388

RESUMEN

The environment of Plasmodium falciparum gametocytes changes when they make the transition from the vertebrate to the invertebrate host. Gametocytes of this species cultivated in vitro were used to evaluate the effect of serum, pH, pCO2 tension, bicarbonate ion, and temperature on gamete formation. Temperature was the only factor responsible for keeping P. falciparum gametocytes in the inactivated state. Mature gametocytes held at temperatures above 30 degrees C remained quiescent in 10% serum, even at low ambient pCO2 tension, alkaline pH, and in the presence of 25 mM bicarbonate ion. When the temperature of the medium was allowed to drop below 30 degrees C, gametocytes emerged from the red blood cells and microgametocytes consistently exflagellated at pH 7.4, even in the absence of bicarbonate ion. With regard to bicarbonate ion, exflagellation in P. falciparum is similar to P. berghei and different from P. gallinaceum gametocytes, which have an obligate requirement for bicarbonate ion.


Asunto(s)
Plasmodium falciparum/fisiología , Animales , Bicarbonatos/farmacología , Sangre , Dióxido de Carbono/farmacología , Medios de Cultivo , Flagelos/efectos de los fármacos , Flagelos/fisiología , Concentración de Iones de Hidrógeno , Plasmodium falciparum/efectos de los fármacos , Plasmodium falciparum/ultraestructura , Temperatura
18.
Am J Trop Med Hyg ; 49(3): 335-40, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8396859

RESUMEN

The elimination of serum from Plasmodium falciparum culture media could decrease costs, enhance procurement, and improve the feasibility of large-scale production of parasite material. We provide a semi-defined, serum-free formulation, of commercially available constituents that supports P. falciparum parasite growth at rates comparable with those obtained with serum-supplemented media. The medium is composed of RPMI 1640 to which HEPES, extra glucose, bicarbonate, and hypoxanthine have been added. Bovine albumin and serum-derived, lipids-cholesterol-rich mixture are then used in place of serum.


Asunto(s)
Medio de Cultivo Libre de Suero , Plasmodium falciparum/crecimiento & desarrollo , Animales , Bicarbonatos/metabolismo , Colesterol/metabolismo , Glucosa/metabolismo , Hipoxantina , Hipoxantinas/metabolismo , Metabolismo de los Lípidos , Albúmina Sérica Bovina/metabolismo , Sodio/metabolismo , Bicarbonato de Sodio
19.
Am J Trop Med Hyg ; 47(6): 852-92, 1992 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1471744

RESUMEN

A total of 407 Leishmania and other Leishmania-like isolates obtained from patients, other vertebrates, sand fly vectors, and other arthropods from Kenya and other countries were characterized and compared with several World Health Organization and other well-characterized reference strains of Leishmania, Trypanosoma, Crithidia, Herpetomonas, and Leptomonas by cellulose acetate electrophoresis (CAE), using 20 enzyme systems. Analysis of the isoenzyme banding patterns (IBP) of the isolates generated isoenzyme profiles that were resolved as zymodemes and tabulated. Isolates that produced similar isoenzyme profiles in all 20 enzyme systems were placed into a particular Leishmania isoenzyme taxon, with the zymodeme designated numerically as Zn. A total of 66 zymodemes were recorded for the 407 isolates studied. To obviate the need to draw all 66 representative IBP for each of the 20 enzyme systems, the 66 zymodemes (Z1-Z66) were again placed into similarity groups represented by pattern number or Pn. This resulted in 23-50 IBP (Pn) per enzyme system. The highest number of IBP scored was for malate dehydrogenase (MDH) (P1-50) and the lowest score was for glucose-6-phosphate isomerase (GPI) (P1-23). From these different isoenzyme profiles or zymodemes, IBP of 14 (MDH, GPI, nucleoside hydrolase, phosphoglucomutase, malic enzyme, isocitrate dehydrogenase, glucose-6-phosphate dehydrogenase, mannose-6-phosphate isomerase, 6-phosphogluconate dehydrogenase, glutamate oxaloacetate transferase/aspartate aminotransferase, glutathione reductase, superoxide dismutase, fumarase, and glyceraldehyde-3-phosphate dehydrogenase) of the 20 enzyme systems were selected for computer-calculated numerical taxonomy. Consistent individual isoenzyme bands with similar relative mobilities of the 14 enzyme systems were scored into groups (allelomorphs, allozymes, or electromorphs) and used in cluster analysis. For each pattern in every profile, the presence of a consistent band was entered as 1 and its absence as 0. A total of 419 allozyme characters (variables) were scored for the 14 enzyme systems. Lastly, all different zymodemes sharing a particular IBP (Pn) within an enzyme system were counted and the total number was shown as a zymodeme frequency (Zf). Final analysis of the CAE isoenzyme profiles and cluster-dendrograms resulted in the identification of several potentially new species and subspecies of Leishmania and other Leishmania-like isolates from patients, sand flies, and animal reservoir hosts collected from Kenya and other locations in Africa. Zymodeme analysis of the Kenyan visceral and cutaneous leishmaniasis isolates resulted in the identification of 11 subpopulations of the L. donovani species complex and six subpopulations of the L. tropica species complex endemic to different geographic areas of Kenya.


Asunto(s)
Vectores Artrópodos/parasitología , Reservorios de Enfermedades , Leishmania/clasificación , Leishmaniasis/parasitología , Psychodidae/parasitología , Animales , Análisis por Conglomerados , Electroforesis en Acetato de Celulosa , Humanos , Isoenzimas/análisis , Kenia/epidemiología , Leishmania/enzimología , Leishmaniasis/epidemiología , Polimorfismo Genético
20.
Am J Trop Med Hyg ; 48(4): 530-5, 1993 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8480861

RESUMEN

In the early 1930s, investigators of visceral leishmaniasis stated that Leishman-Donovan bodies are found in body fluids of kala-azar patients, for example, in urine, feces, semen, and nasal and pharyngeal secretions. Based on this finding, we investigated the diagnostic potential of nasal secretions, tonsillopharyngeal mucosal swabs, and urine centrifugates inoculated into Schneider's Drosophila Medium (containing antibiotics and antifungal agents) as well as with Giemsa-stained smears. Consequently, 64 randomly selected patients with visceral leishmaniasis from Kenya (59 who were splenic culture or Giemsa stain positive and five who were culture negative but Giemsa stain positive) were tested by three noninvasive methods. These tests were all performed before the patients were treated with Pentostam. Cultures of nasal and tonsillopharyngeal swabs and urine centrifugates produced 28 positive samples representing 24 patients (37.5%). Moreover, a set of 25 Giemsa-stained slide smears made from the nasal and tonsillopharyngeal mucosa of 25 patients with visceral leishmaniasis who had not tested positive in cultures produced nine positives. Therefore, the overall total of patients who tested positive by all of the above methods was 33 or 51.6%. The cryopreserved Leishmania isolates were characterized by cellulose acetate electrophoresis using 20 enzyme systems. The isoenzyme profiles produced by the parasites were represented in five different L. donovani s.l. zymodemes. Representatives of these isolates were also characterized by DNA Southern blotting analysis, which corroborated the isoenzyme results.


Asunto(s)
Leishmania donovani/aislamiento & purificación , Leishmaniasis Visceral/parasitología , Mucosa Nasal/parasitología , Faringe/parasitología , Orina/parasitología , Adolescente , Adulto , Animales , Niño , Preescolar , Criopreservación , Electroforesis en Acetato de Celulosa , Humanos , Lactante , Isoenzimas/análisis , Kenia/epidemiología , Leishmania donovani/clasificación , Leishmania donovani/enzimología , Leishmaniasis Visceral/diagnóstico , Leishmaniasis Visceral/epidemiología , Persona de Mediana Edad , Membrana Mucosa/parasitología , Tonsila Palatina/parasitología
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