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1.
Rev Med Chil ; 146(11): 1294-1303, 2018 Nov.
Artículo en Español | MEDLINE | ID: mdl-30725043

RESUMEN

BACKGROUND: The high academic burden may hamper the quality of life of medical students. AIM: To evaluate the quality of life (QOL) for medical students attending a Chilean university. MATERIAL AND METHODS: Four hundred eleven medical students aged 22 ± 2 years (51% women), studying in Santiago, Chile, answered online a validated Spanish version of the WHOQOL-BREF quality of life survey (scored from 0 to 100). Overall scores were assessed for the questionnaire domains Physical health, Psychological health, Interpersonal relationships, and Environment. RESULTS: The global scores were 65.1 for Physical health, 63.1 for Psychological health, 61.3 for Interpersonal relationships and 67.2 for Environment. Students in clinical practice, females, those with sedentary behaviors and consuming modafinil had lower Physical health scores. Students coming from outside Santiago, with sedentary behaviors and who consumed modafinil had poorer Psychological health scores. Students coming from outside Santiago, males and those with sedentary behaviors had Lower Interpersonal relationship scores. Environment scores were also lower among students who were sedentary or from outside Santiago. CONCLUSIONS: The variables that had a greater negative impact in the quality of life of these students were the transition from theoretical courses to clinical practice, being from outside Santiago, being overweight or obese and consuming modafinil. Students that were physically active had better quality of life scores.


Asunto(s)
Calidad de Vida , Estudiantes de Medicina/estadística & datos numéricos , Adolescente , Adulto , Análisis de Varianza , Índice de Masa Corporal , Estimulantes del Sistema Nervioso Central/uso terapéutico , Chile , Estudios Transversales , Educación de Pregrado en Medicina/estadística & datos numéricos , Femenino , Estado de Salud , Humanos , Relaciones Interpersonales , Masculino , Modafinilo/uso terapéutico , Satisfacción Personal , Valores de Referencia , Estudiantes de Medicina/psicología , Encuestas y Cuestionarios , Adulto Joven
2.
Transfus Med ; 27(4): 286-291, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28524366

RESUMEN

BACKGROUND: Blood donors are, in principle, healthy individuals who may be revealed as infectious for blood-borne agents by the laboratory screening process, depicting the asymptomatic burden of the disease. Therefore, monitoring hepatitis C virus (HCV)-infected donor and human immunodeficiency virus (HIV)-infected donor and associating to their demographical and behavioural characteristics may shed light on the dynamics and contemporary changes in these viruses' epidemiology. METHODS: Donors presenting repeatedly reactive HCV or HIV serology/nucleic acid testing (NAT) screening results were submitted to confirmatory testing. Confirmed positive donors were invited to return to the blood bank for notification and counselling when a follow-up sample was obtained and an interview performed to eventually disclose potential risks. HCV- or HIV-infected donors identified over 11 years of screening (2004-2015) were evaluated for demographic and behavioural parameters. RESULTS: In the period, 139 160 donations were screened, and 36 (0.025%) were found positive for HIV, stemming from 29 male and 7 female donors. Among those, eight subjects were repeat donors. A total of 95 donations were found repeatedly reactive for HCV (0.068%), obtained from 60 men and 35 women. Noticeably, in despite of a higher HCV prevalence in the donor population, the incidence of HIV among repeat donors was 10 times that of HCV (18 × 1.6/100 000 persons-year, respectively). On average, HIV-seroreactive men were found to be younger (mean = 34 years old) than women (mean = 40 years old). A total of 10 donors acknowledged sexual behaviours not previously informed, including 2 who were aware of their HIV-positive status and another 2 who admitted to be seeking HIV testing. No window period donation was verified. DISCUSSION: The majority of the HIV-infected donors are young males who deny risk factors in the interview and also ignore the confidence self-exclusion opportunity. As they may reiterate this behaviour in serial donations, use of the most sensitive laboratory testing is justified in this setting.


Asunto(s)
Donantes de Sangre , Selección de Donante/métodos , Infecciones por VIH , Hepatitis C , Técnicas de Amplificación de Ácido Nucleico , ARN Viral/sangre , Adulto , Brasil/epidemiología , Femenino , Infecciones por VIH/sangre , Infecciones por VIH/epidemiología , Hepatitis C/sangre , Hepatitis C/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Estudios Seroepidemiológicos
3.
Rev Med Chil ; 144(11): 1391-1399, 2016 Nov.
Artículo en Español | MEDLINE | ID: mdl-28394955

RESUMEN

BACKGROUND: The delay in the diagnosis of AIDS results in higher treatment costs. AIM: To reveal the experiences of people who were diagnosed in the AIDS stage about the access to the ELISA test. MATERIAL AND METHODS: In depth interviews were carried out to 15 participants from public hospitals who were in the AIDS stage at the moment of the diagnosis. The main questions asked were about the motivations to take the test, the barriers found and the help received from the health care personnel. All interviews were recorded and analyzed according to Kripperdorff. RESULTS: The three categories that emerged were the motivations to take the test, the facilitators found and the difficulties to access to the test. The main motivation was a condition of vulnerability due to the suspicion or certainty of being infected. The main facilitator was the sensation of being accepted and not discriminated. The main difficulties were the fear of having a positive test and of being discriminated and the lack of information. CONCLUSIONS: Knowing these experiences will help to improve the early detection of HIV infections.


Asunto(s)
Serodiagnóstico del SIDA , Síndrome de Inmunodeficiencia Adquirida/diagnóstico , Síndrome de Inmunodeficiencia Adquirida/psicología , Ensayo de Inmunoadsorción Enzimática/psicología , Percepción , Adulto , Anciano , Chile , Diagnóstico Tardío , Diagnóstico Precoz , Femenino , Humanos , Masculino , Persona de Mediana Edad , Investigación Cualitativa , Asunción de Riesgos , Discriminación Social
4.
Ginecol Obstet Mex ; 84(5): 301-5, 2016 May.
Artículo en Español | MEDLINE | ID: mdl-27476251

RESUMEN

OBJECTIVE: To determine the frequency of menstrual disorders in gynecology and obstetrics residents. MATERIAL AND MET HODS: All residents of the 2015-2016 academic cycle were studied. In all them the menstrual cycle characteristics such as: rhythm, duration and quantity were analyzed. For statistical analysis Mann Whitney U test and Spearman's correlation analysis were done. RESULTS: 61 residents, 18 of 2nd, 21 of 3rd and 22 of 4th year were studied. Body mass index was significantly greater in those of 4th grade when compared with those of 2nd. The waist hip ratio (WHR) was significantly smaller in those of 3rd when compared with those of 4th. The reported frequency of menstrual disturbances was 22.8%, 28.6% and 22.7% for the 2nd, 3rd and 4th years respectively. After comparing the groups, between them the total volume was greater in those of 2nd when compared with those of 3rd (p<0.009) and 4th (p<0.04) In the correlation analysis in those of 2nd grade the WHR negatively correlated with the duration of bled (p <0.483, p<0.049). In those of 3rd year the WHR positively correlated with the duration (p 0.544, p<0.024) and with the total volume (p 0.553, p<0.02 1). In those of 4th year any correlation was found. CONCLUSION: The 2nd year residents women's are more likely to suffer menstrual disorders compared with those of 3rd and 4th ear of residence.


Asunto(s)
Ginecología , Internado y Residencia , Trastornos de la Menstruación/epidemiología , Obstetricia , Adulto , Femenino , Ginecología/educación , Humanos , Obstetricia/educación
6.
J Exp Med ; 194(4): 551-5, 2001 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-11514610

RESUMEN

Allergic asthmatic responses in the airway are associated with airway hyperreactivity, eosinophil accumulation in the lung, and cytokine production by allergen-specific, T helper cell type 2 (Th2) lymphocytes. Here, we show that in a cockroach antigen (CA) model of allergic pulmonary inflammation, the chemokine macrophage inflammatory protein (MIP)-3alpha is expressed in the lung within hours of allergen challenge. To determine the biologic relevance of this expression, mice lacking CCR6, the only known receptor for MIP-3alpha, were studied for their response to CA. CCR6-deficient mice were immunized to the same extent as their wild-type counterparts, as judged by cytokine production in antigen-challenged lymphocytes. However, compared with CA-challenged wild-type mice, challenged CCR6-deficient mice had reduced airway resistance, fewer eosinophils around the airway, lower levels of interleukin 5 in the lung, and reduced serum levels of immunoglobulin E. Together, these data demonstrate that MIP-3alpha and CCR6 function in allergic pulmonary responses and suggest that these molecules might represent novel therapeutic targets for treatment of asthma.


Asunto(s)
Asma/fisiopatología , Hipersensibilidad/fisiopatología , Neumonía/fisiopatología , Receptores de Quimiocina/fisiología , Animales , Asma/inmunología , Asma/metabolismo , Citocinas/metabolismo , Hipersensibilidad/inmunología , Hipersensibilidad/metabolismo , Inmunoglobulina E/biosíntesis , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neumonía/inmunología , Neumonía/metabolismo , Receptores CCR6 , Receptores de Quimiocina/genética , Receptores de Quimiocina/metabolismo , Células Th2/inmunología , Células Th2/metabolismo
7.
J Exp Med ; 190(8): 1183-8, 1999 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-10523616

RESUMEN

6Ckine is an unusual chemokine capable of attracting naive T lymphocytes in vitro. It has been recently reported that lack of 6Ckine expression in lymphoid organs is a prominent characteristic of mice homozygous for the paucity of lymph node T cell (plt) mutation. These mice show reduced numbers of T cells in lymph nodes, Peyer's patches, and the white pulp of the spleen. The genetic reason for the lack of 6Ckine expression in the plt mouse, however, has remained unknown. Here we demonstrate that mouse 6Ckine is encoded by two genes, one of which is expressed in lymphoid organs and is deleted in plt mice. A second 6Ckine gene is intact and expressed in the plt mouse.


Asunto(s)
Quimiocinas CC/genética , Eliminación de Gen , Animales , Southern Blotting , Quimiocina CCL21 , Quimiocinas/genética , Clonación Molecular , Regulación de la Expresión Génica/inmunología , Marcación de Gen , Ratones , Ratones Endogámicos , Datos de Secuencia Molecular , Mutación , Reacción en Cadena de la Polimerasa , Análisis de Secuencia , Linfocitos T/metabolismo
8.
J Exp Med ; 191(3): 445-54, 2000 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-10662790

RESUMEN

Human herpesvirus 8 (HHV8, also known as Kaposi's sarcoma [KS]-associated herpesvirus) has been implicated as an etiologic agent for KS, an angiogenic tumor composed of endothelial, inflammatory, and spindle cells. Here, we report that transgenic mice expressing the HHV8-encoded chemokine receptor (viral G protein-coupled receptor) within hematopoietic cells develop angioproliferative lesions in multiple organs that morphologically resemble KS lesions. These lesions are characterized by a spectrum of changes ranging from erythematous maculae to vascular tumors, by the presence of spindle and inflammatory cells, and by expression of vGPCR, CD34, and vascular endothelial growth factor. We conclude that vGPCR contributes to the development of the angioproliferative lesions observed in these mice and suggest that this chemokine receptor may play a role in the pathogenesis of KS in humans.


Asunto(s)
Herpesvirus Humano 8/genética , Receptores de Quimiocina/genética , Sarcoma de Kaposi/virología , Infecciones Tumorales por Virus , Proteínas Virales/genética , Animales , Antígenos CD2/genética , Transformación Celular Neoplásica/genética , Células Cultivadas , Modelos Animales de Enfermedad , Factores de Crecimiento Endotelial/metabolismo , Endotelio Vascular/metabolismo , Endotelio Vascular/patología , Neoplasias Cardíacas/patología , Células Madre Hematopoyéticas/metabolismo , Linfocinas/metabolismo , Ratones , Ratones Transgénicos , Proteínas Tirosina Quinasas Receptoras/metabolismo , Receptores de Quimiocina/biosíntesis , Receptores de Factores de Crecimiento/metabolismo , Receptores de Factores de Crecimiento Endotelial Vascular , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sarcoma de Kaposi/patología , Sarcoma de Kaposi/ultraestructura , Neoplasias Cutáneas/patología , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular , Proteínas Virales/biosíntesis
9.
J Exp Med ; 180(6): 2039-48, 1994 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-7964481

RESUMEN

Transgenic mice expressing the chemokine N51/KC in thymus, skin, and tongue showed a marked infiltration of a single class of inflammatory cells (neutrophils) in the sites of transgene expression. In the thymus, neutrophils were most numerous in the cortex and juxta-medullary regions, often forming aggregates or clusters. A similar, but less intense, neutrophilic infiltrate occurred in close proximity to the epidermal basal layer of the tongue and skin. No morphologic evidence of injury was observed in the thymus, skin, or tongue of these transgenic mice, indicating that N51/KC expression induces recruitment but not inflammatory activation of neutrophils. The lack of activation in the thymus resulted in a large senescent neutrophilic population that was phagocytosed by thymic macrophages and epithelial-reticular cells. These results indicate that N51/KC is a neutrophil chemoattractant in vivo and establish these transgenic mice as effective models to study the phenomena of recruitment and clearance of neutrophils, events that are critical for the initiation and resolution of the inflammatory response.


Asunto(s)
Quimiocinas CXC , Factores Quimiotácticos/biosíntesis , Expresión Génica , Sustancias de Crecimiento/biosíntesis , Péptidos y Proteínas de Señalización Intercelular , Neutrófilos/metabolismo , Piel/metabolismo , Timo/metabolismo , Envejecimiento/metabolismo , Animales , Secuencia de Bases , Quimiocina CXCL1 , Hormona del Crecimiento/biosíntesis , Hormona del Crecimiento/genética , Humanos , Inflamación/fisiopatología , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Ratones Transgénicos , Microscopía Electrónica , Datos de Secuencia Molecular , Neutrófilos/fisiología , Oligodesoxirribonucleótidos , Timo/crecimiento & desarrollo , Timo/ultraestructura , Lengua/metabolismo
10.
J Exp Med ; 193(5): 573-84, 2001 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-11238588

RESUMEN

Chemokine receptors transduce signals important for the function and trafficking of leukocytes. Recently, it has been shown that CC chemokine receptor (CCR)8 is selectively expressed by Th2 subsets, but its functional relevance is unclear. To address the biological role of CCR8, we generated CCR8 deficient (-/-) mice. Here we report defective T helper type 2 (Th2) immune responses in vivo in CCR8(-/)- mice in models of Schistosoma mansoni soluble egg antigen (SEA)-induced granuloma formation as well as ovalbumin (OVA)- and cockroach antigen (CRA)-induced allergic airway inflammation. In these mice, the response to SEA, OVA, and CRA showed impaired Th2 cytokine production that was associated with aberrant type 2 inflammation displaying a 50 to 80% reduction in eosinophils. In contrast, a prototypical Th1 immune response, elicited by Mycobacteria bovis purified protein derivative (PPD) was unaffected by CCR8 deficiency. Mechanistic analyses indicated that Th2 cells developed normally and that the reduction in eosinophil recruitment was likely due to systemic reduction in interleukin 5. These results indicate an important role for CCR8 in Th2 functional responses in vivo.


Asunto(s)
Eosinófilos/inmunología , Hipersensibilidad/inmunología , Receptores de Quimiocina/deficiencia , Células Th2/inmunología , Administración por Inhalación , Animales , Antígenos/administración & dosificación , Antígenos/inmunología , Cucarachas/inmunología , Citocinas/genética , Citocinas/metabolismo , Relación Dosis-Respuesta Inmunológica , Eosinófilos/citología , Granuloma/inmunología , Granuloma/patología , Hipersensibilidad/genética , Hipersensibilidad/patología , Inmunidad Celular/genética , Inmunidad Celular/inmunología , Inyecciones Subcutáneas , Interleucina-5/sangre , Pulmón/metabolismo , Pulmón/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ovalbúmina/administración & dosificación , Ovalbúmina/inmunología , Óvulo/inmunología , ARN Mensajero/metabolismo , Receptores CCR8 , Receptores de Quimiocina/genética , Schistosoma mansoni/inmunología , Células TH1/inmunología
11.
Int J Tuberc Lung Dis ; 24(10): 1000-1008, 2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-33126931

RESUMEN

SETTING: Two consecutive trials were conducted to evaluate the effectiveness of a public health approach to identify and correct problems in the care cascade for household contacts (HHCs) of TB patients in three Brazilian high TB incidence cities.METHODS: In the first trial, 12 clinics underwent standardised evaluation using questionnaires administered to TB patients, HHCs and healthcare workers, and analysis of the cascade of latent TB care among HHCs. Six clinics were then randomised to receive interventions to strengthen management of latent TB infection (LTBI), including in-service training provided by nurses, work process organisation and additional clinic-specific solutions. In the second trial, a similar but streamlined evaluation was conducted in two clinics, who then received initial and subsequent intensive in-service training provided by a physician.RESULTS: In the evaluation phase of both trials, many HHCs were identified, but few started LTBI treatment. After the intervention, the number of HHCs initiating treatment per 100 active TB patients increased by 10 (95%CI - 11 to 30) in the first trial, and by 44 (95%CI 26 to 61) in the second trial.DISCUSSION: A public health approach with standardised evaluation, local decisions for improvements, followed by intensive initial and in-service training appears promising for improved LTBI management.


Asunto(s)
Tuberculosis Latente , Brasil , Ciudades , Humanos , Incidencia , Tuberculosis Latente/diagnóstico , Tuberculosis Latente/tratamiento farmacológico , Tuberculosis Latente/epidemiología , Salud Pública
12.
Neuron ; 1(4): 311-20, 1988 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3078520

RESUMEN

Gene expression may occur in unexpected ectopic sites when diverse genetic elements are juxtaposed as chimeric genes in transgenic mice. To determine the specific contribution of the promoter and reporter gene in ectopic expression, we have analyzed the expression of 14 different fusion genes in transgenic mice. Chimeric genes containing the mouse metallothionein-I promoter linked to either the rat or human growth hormone gene or the calcitonin/CGRP gene are expressed in a very similar pattern of neuronal regions. This ectopic expression is not a unique feature of the metallothionein promoter, since transferring the human growth hormone gene to four other heterologous promoters resulted in varying degrees of ectopic expression in overlapping subsets of cortical and hypothalamic neurons. The novel pattern of ectopic expression suggests that these otherwise unrelated neurons share a common developmental regulatory machinery for activation of gene transcription.


Asunto(s)
Quimera , Expresión Génica , Genes , Neuronas/metabolismo , Animales , Calcitonina/genética , Péptido Relacionado con Gen de Calcitonina/genética , Técnica del Anticuerpo Fluorescente , Hormona del Crecimiento/genética , Metalotioneína/genética , Ratones , Ratones Transgénicos , Hibridación de Ácido Nucleico , Regiones Promotoras Genéticas , Sondas ARN
13.
J Clin Invest ; 98(2): 529-39, 1996 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-8755666

RESUMEN

Chemokines (pro-inflammatory chemoattractant cytokines) are expressed in pathological conditions of the central nervous system (CNS). Previous studies suggested that the CNS is relatively resistant to leukocyte diapedesis after chemokine injection, leaving their functional role unresolved. The CNS function of N51/KC, a neutrophil-selective chemokine, was addressed by expressing N51/KC under control of the myelin basic protein (MBP) promoter in transgenic (tg) mice (MBP-N51/KC mice). CNS-specific N51/KC expression produced remarkable neutrophil infiltration into perivascular, meningeal, and parenchymal sites, demonstrating that this chemokine exerts the multiple functions in vivo required to recruit leukocytes into the CNS. MBP-N5 1/KC mice represent an incisive model for the molecular dissection of neutrophil entry into the CNS. Unexpectedly, MBP-N51/KC mice developed a neurological syndrome of pronounced postural instability and rigidity at high frequency beginning at 40 days of age, well after peak chemokine expression. 68/182 mice in one tg fine were found dead before one year of age, with prominent neurological symptoms premortem in 26 (38%). Florid microglial activation and blood-brain barrier disruption without dysmyelination were the major neuropathological alterations. Late-onset neurological symptoms in MBP-N51/KC mice may indicate unanticipated consequences of CNS chemokine expression.


Asunto(s)
Quimiocinas CXC , Factores Quimiotácticos/biosíntesis , Citocinas/biosíntesis , Sustancias de Crecimiento/biosíntesis , Péptidos y Proteínas de Señalización Intercelular , Enfermedades del Sistema Nervioso/fisiopatología , Neuroglía/fisiología , Neutrófilos/fisiología , Oligodendroglía/fisiología , Animales , Astrocitos/patología , Secuencia de Bases , Encéfalo/patología , Encéfalo/fisiopatología , Quimiocina CXCL1 , Quimiocinas , Factores Quimiotácticos/genética , Citocinas/genética , Cartilla de ADN , Femenino , Sustancias de Crecimiento/genética , Intrones , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Ratones Endogámicos ICR , Ratones Transgénicos , Microscopía Electrónica , Datos de Secuencia Molecular , Proteína Básica de Mielina/biosíntesis , Proteína Básica de Mielina/genética , Enfermedades del Sistema Nervioso/genética , Enfermedades del Sistema Nervioso/patología , Neuroglía/patología , Neutrófilos/patología , Neutrófilos/ultraestructura , Oligodendroglía/patología , Reacción en Cadena de la Polimerasa , Postura , Regiones Promotoras Genéticas , Proteínas Recombinantes de Fusión/biosíntesis , Mapeo Restrictivo
14.
J Clin Invest ; 108(12): 1789-96, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11748262

RESUMEN

ORF74 (or KSHV-vGPCR) is a highly constitutively active G protein-coupled receptor encoded by HHV8 that is regulated both positively and negatively by endogenous chemokines. When expressed in transgenic mice, this chemokine receptor induces an angioproliferative disease closely resembling Kaposi sarcoma (KS). Here we demonstrate that several lines of mice carrying mutated receptors deficient in either constitutive activity or chemokine regulation fail to develop KS-like disease. In addition, animals expressing a receptor that preserves chemokine binding and constitutive activity but that does not respond to agonist stimulation have a much lower incidence of angiogenic lesions and tumors. These results indicate that induction of the KS-like disease in transgenic mice by ORF74 requires not only high constitutive signaling activity but also modulation of this activity by endogenous chemokines.


Asunto(s)
Quimiocinas/fisiología , Receptores de Quimiocina/fisiología , Sarcoma de Kaposi/etiología , Proteínas Virales/fisiología , Secuencia de Aminoácidos , Animales , Células COS , Ligandos , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Ratones Transgénicos , Datos de Secuencia Molecular , Neovascularización Patológica/etiología , Sarcoma de Kaposi/prevención & control , Transducción de Señal
15.
J Clin Invest ; 107(12): 1591-8, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11413167

RESUMEN

ADP plays a critical role in modulating thrombosis and hemostasis. ADP initiates platelet aggregation by simultaneous activation of two G protein-coupled receptors, P2Y1 and P2Y12. Activation of P2Y1 activates phospholipase C and triggers shape change, while P2Y12 couples to Gi to reduce adenylyl cyclase activity. P2Y12 has been shown to be the target of the thienopyridine drugs, ticlopidine and clopidogrel. Recently, we cloned a human orphan receptor, SP1999, highly expressed in brain and platelets, which responded to ADP and had a pharmacological profile similar to that of P2Y12. To determine whether SP1999 is P2Y12, we generated SP1999-null mice. These mice appear normal, but they exhibit highly prolonged bleeding times, and their platelets aggregate poorly in responses to ADP and display a reduced sensitivity to thrombin and collagen. These platelets retain normal shape change and calcium flux in response to ADP but fail to inhibit adenylyl cyclase. In addition, oral clopidogrel does not inhibit aggregation responses to ADP in these mice. These results demonstrate that SP1999 is indeed the elusive receptor, P2Y12. Identification of the target receptor of the thienopyridine drugs affords us a better understanding of platelet function and provides tools that may lead to the discovery of more effective antithrombotic therapies.


Asunto(s)
Plaquetas/efectos de los fármacos , Fibrinolíticos/farmacología , Proteínas de la Membrana , Antagonistas del Receptor Purinérgico P2 , Ticlopidina/farmacología , Adenosina Difosfato/farmacología , Adenilil Ciclasas/metabolismo , Animales , Tiempo de Sangría , Coagulación Sanguínea , Plaquetas/metabolismo , Células Cultivadas , Clopidogrel , Marcación de Gen , Cinética , Ratones , Ratones Noqueados , Agregación Plaquetaria/efectos de los fármacos , Receptores Purinérgicos P2/genética , Receptores Purinérgicos P2Y12 , Ticlopidina/análogos & derivados
16.
Mol Cell Biol ; 15(7): 3523-30, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7791759

RESUMEN

RelA (p65) is one of the strongest activators of the Rel/NF-kappa B family. As a first step to elucidate the mechanisms that regulate its activity in vivo, we have generated transgenic mice overexpressing RelA in the thymus. Although the levels of RelA were significantly increased in thymocytes of transgenic mice, the overall NF-kappa B-binding activity in unstimulated cells was not augmented compared with that in control thymocytes. This could be explained by the dramatic increase of endogenous I kappa B alpha levels observed in RelA-overexpressing cells in both cytoplasmic and nuclear compartments. The ikba mRNA levels were not augmented by overexpressed RelA, but I kappa B alpha inhibitor was found to be stabilized through association with RelA. Although a fraction of RelA was associated with cytoplasmic p105, no changes in the precursor levels were observed. Upon stimulation of RelA-overexpressing thymocytes with phorbol 12-myristate 13-acetate and lectin (phytohemaglutinin), different kappa B-binding complexes, including RelA homodimers, were partially released from I kappa B alpha. Association of RelA with I kappa B alpha prevented complete degradation of the inhibitor. No effect of phorbol 12-myristate 13-acetate-lectin treatment was detected on RelA associated with p105. Our data indicate that cytoplasmic retention of overexpressed RelA by I kappa B alpha is the major in vivo mechanism controlling the potential excess of NF-kappa B activity in long-term RelA-overexpressing thymocytes.


Asunto(s)
Proteínas de Unión al ADN/biosíntesis , Proteínas I-kappa B , FN-kappa B/metabolismo , Timo/metabolismo , Transactivadores/metabolismo , Animales , Secuencia de Bases , Northern Blotting , Western Blotting , Células Cultivadas , Ratones , Ratones Endogámicos , Ratones Transgénicos , Datos de Secuencia Molecular , Inhibidor NF-kappaB alfa , FN-kappa B/antagonistas & inhibidores , FN-kappa B/genética , Subunidad p50 de NF-kappa B , Fitohemaglutininas/farmacología , Pruebas de Precipitina , Unión Proteica , Precursores de Proteínas/metabolismo , Linfocitos T/metabolismo , Acetato de Tetradecanoilforbol/farmacología , Timo/citología , Distribución Tisular , Transactivadores/genética , Factor de Transcripción ReIA
17.
Mol Cell Biol ; 12(1): 120-7, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1729594

RESUMEN

The gene encoding mZP3, the mouse sperm receptor, is expressed exclusively in growing oocytes during oogenesis. To investigate the molecular basis of oocyte-specific mZP3 gene expression, we generated several lines of mice harboring a transgene that contains 470 bp of mZP3 gene 5'-flanking sequence (nucleotides -470 to +10) fused to the firefly luciferase gene coding region. Three of four expressing transgenic lines exhibited luciferase activity only in growing oocytes, suggesting that the 470-bp fragment is sufficient to direct Iocyte-specific expression of the luciferase gene. Results of DNase I footprinting and gel mobility shift assays suggested the presence of an ovary-specific protein that binds to a small region (nucleotides-99 to -86) within the 470-bp fragment of the mZP3 promoter, with 5'-G(G/A)T(G/A)A-3' representing the minimal sequence required for binding. Southwestern (DNA-protein) gel blots revealed the presence of an oocyte-specific, approximately 60,000-Mr protein, called OSP-1, that binds to the minimal sequence. Changes in levels of OSP-1 during oogenesis and early cleavage are consistent with the pattern of mZP3 gene expression during these developmental stages in mice. Therefore, OSP-1 may be a mammalian oocyte-specific transcription factor involved in regulating oocyte-specific mZP3 gene expression.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Proteínas del Huevo , Regulación de la Expresión Génica , Glicoproteínas/genética , Glicoproteínas de Membrana , Oocitos/metabolismo , Regiones Promotoras Genéticas , Receptores de Superficie Celular , Animales , Secuencia de Bases , Unión Competitiva , ADN , Luciferasas/metabolismo , Ratones , Ratones Transgénicos , Datos de Secuencia Molecular , Glicoproteínas de la Zona Pelúcida
18.
Mol Cell Biol ; 16(4): 1342-8, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8657107

RESUMEN

Previous studies have indicated that Bcl-3 interacts through its ankyrin repeats with the transcriptional factors NF-kappaB1 (p50) and NF-kappaB2 (p52), affecting their biological activities. To further investigate the role of Bcl-3 in vivo and its association with the NF-kappaB proteins, we have generated transgenic mice constitutively expressing Bcl-3 in thymocytes. The results indicate that Bcl-3 is associated with endogenous p50 and p52 in nuclear extracts from transgenic animals. Remarkably, constitutive expression of Bcl-3 in these cells augments the DNA binding activity of p52 homodimers. This effect could be reproduced in vitro and is blocked by anti-Bcl-3 antibodies. We have also shown that Bcl-3 is phosphorylated in thymocytes and that its dephosphorylation greatly decreases the effect on p50 homodimers.


Asunto(s)
ADN/metabolismo , FN-kappa B/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Timo/metabolismo , Activación Transcripcional , Animales , Ancirinas/metabolismo , Proteínas del Linfoma 3 de Células B , Western Blotting , Células Cultivadas , Citometría de Flujo , Ratones , Ratones Transgénicos , Fosforilación , Secuencias Repetitivas de Ácidos Nucleicos , Timo/citología , Factores de Transcripción
19.
Mol Cell Biol ; 21(9): 3159-65, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11287620

RESUMEN

Fractalkine (CX(3)CL1) is the first described chemokine that can exist either as a soluble protein or as a membrane-bound molecule. Both forms of fractalkine can mediate adhesion of cells expressing its receptor, CX(3)CR1. This activity, together with its expression on endothelial cells, suggests that fractalkine might mediate adhesion of leukocytes to the endothelium during inflammation. Fractalkine is also highly expressed in neurons, and its receptor, CX(3)CR1, is expressed on glial cells. To determine the biologic role of fractalkine, we used targeted gene disruption to generate fractalkine-deficient mice. These mice did not exhibit overt behavioral abnormalities, and histologic analysis of their brains did not reveal any gross changes compared to wild-type mice. In addition, these mice had normal hematologic profiles except for a decrease in the number of blood leukocytes expressing the cell surface marker F4/80. The cellular composition of their lymph nodes did not differ significantly from that of wild-type mice. Similarly, the responses of fractalkine(-/-) mice to a variety of inflammatory stimuli were indistinguishable from those of wild-type mice.


Asunto(s)
Quimiocinas CX3C , Quimiocinas CXC/inmunología , Proteínas de la Membrana/inmunología , Animales , Linfocitos T CD4-Positivos/citología , Linfocitos T CD8-positivos/citología , Quimiocina CX3CL1 , Quimiocinas CXC/análisis , Quimiocinas CXC/genética , Citometría de Flujo/métodos , Expresión Génica , Marcación de Gen , Intestino Delgado/citología , Intestino Delgado/inmunología , Listeria monocytogenes/inmunología , Proteínas de la Membrana/análisis , Proteínas de la Membrana/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , ARN/análisis , Tioglicolatos/administración & dosificación , Tioglicolatos/inmunología
20.
Braz J Med Biol Res ; 50(10): e6361, 2017 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-28876366

RESUMEN

Diabetes mellitus is one of the most common chronic degenerative diseases, and it is estimated to increase worldwide to around 415 million and to impact 642 million in 2040. Research shows that some plants are sources of bioactive compounds against diabetes. Thus, the objective of this work was to evaluate the oral toxicity and the hypoglycemic effect of the aqueous extract of the leaves of Cnidoscolus quercifolius Pohl. Diabetes was induced in Swiss mice with streptozotocin and the mice were treated with an aqueous extract of C. quercifolius leaves for a period of 30 days. Phytochemical analysis showed that the extract was rich in flavonoids, catechins and triterpenoid, which did not show any mortality and behavioral alterations in mice treated with 200, 1000, and 2000 mg/kg body weight of the extract for 14 days. Histopathological analysis of organs (kidney, pancreas, liver) from mice treated with the 2000 mg/kg extract revealed no architectural change. In the present study, we found a 29% reduction in glucose levels in animals receiving 200 mg/kg body weight. These results are very promising because they showed that C. quercifolius had a hypoglycemic effect and did not present oral toxicity, thus being a new source of compounds for the control of diabetes.


Asunto(s)
Diabetes Mellitus Experimental/tratamiento farmacológico , Euphorbiaceae/química , Hipoglucemiantes/uso terapéutico , Extractos Vegetales/uso terapéutico , Animales , Femenino , Hipoglucemiantes/toxicidad , Riñón/efectos de los fármacos , Dosificación Letal Mediana , Hígado/efectos de los fármacos , Masculino , Ratones , Páncreas/efectos de los fármacos , Extractos Vegetales/toxicidad , Estreptozocina , Pruebas de Toxicidad
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