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1.
Phys Med Biol ; 64(15): 155010, 2019 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-31234149

RESUMEN

Scanning small-angle x-ray scattering (SAXS) measurements were performed on 36 formalin-fixed breast tissue biopsies obtained from two patients. All samples contained microcalcifications of type II, i.e. formed by hydroxyapatite. We demonstrate the feasibility of classifying breast lesions by scanning SAXS of tissues containing microcalcifications with a resolution of 35 [Formula: see text]m [Formula: see text] 30 [Formula: see text]m. We report a characteristic Bragg peak found around q = 1.725 nm-1 that occurs primarily for malignant lesions. Such a clear SAXS fingerprint is potentially linked to structural changes of breast tissue and corresponds to dimensions of about 3.7 nm. This material property could be used as an early indicator of malignancy development, as it is readily assessed by SAXS. If this fingerprint is combined with other known SAXS features, which also indicate the level of malignancy, such as lipid spacing and collagen periodicity, it could complement traditional pathology-based analyses. To confirm the SAXS-based classification, a histopathological workup and a gold standard histopathological diagnosis were conducted to determine the malignancy level of the lesions. Our aim is to report this SAXS fingerprint, which is clearly related to malignant breast lesions. However, any further conclusion based on our dataset is limited by the low number of patients and samples. Running a broad study to increase the number of samples and patients is of great importance and relevance for the breast-imaging community.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Calcinosis/diagnóstico por imagen , Radiografía/métodos , Dispersión del Ángulo Pequeño , Difracción de Rayos X/métodos , Mama/patología , Femenino , Humanos , Radiografía/normas , Cintigrafía
2.
J Appl Crystallogr ; 51(Pt 5): 1378-1386, 2018 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-30279640

RESUMEN

In most cases, the analysis of small-angle and wide-angle X-ray scattering (SAXS and WAXS, respectively) requires a theoretical model to describe the sample's scattering, complicating the interpretation of the scattering resulting from complex heterogeneous samples. This is the reason why, in general, the analysis of a large number of scattering patterns, such as are generated by time-resolved and scanning methods, remains challenging. Here, a model-free classification method to separate SAXS/WAXS signals on the basis of their inflection points is introduced and demonstrated. This article focuses on the segmentation of scanning SAXS/WAXS maps for which each pixel corresponds to an azimuthally integrated scattering curve. In such a way, the sample composition distribution can be segmented through signal classification without applying a model or previous sample knowledge. Dimensionality reduction and clustering algorithms are employed to classify SAXS/WAXS signals according to their similarity. The number of clusters, i.e. the main sample regions detected by SAXS/WAXS signal similarity, is automatically estimated. From each cluster, a main representative SAXS/WAXS signal is extracted to uncover the spatial distribution of the mixtures of phases that form the sample. As examples of applications, a mudrock sample and two breast tissue lesions are segmented.

3.
Rev. chil. cir ; 70(2): 104-111, 2018. tab, ilus
Artículo en Español | LILACS | ID: biblio-959357

RESUMEN

Resumen Objetivo: El objetivo de este estudio fue evaluar el papel de los mastocitos en la respuesta inflamatoria posoperatoria tras el implante de mallas protésicas para la reparación de defectos de la pared abdominal en biomodelos rata Wistar. Materiales y Métodos: Se fabricó una malla de fibroma entretejiendo sus hilos. Se utilizaron 25 ratas Wistar macho adultas, a las cuales se les creó un defecto quirúrgico de 30 × 20 mm en la pared abdominal anterior. Este defecto anatómico fue posteriormente reparado con uno de los dos tipos de mallas previamente esterilizadas, las cuales fueron la malla de fibroína, y la malla comercial ultrapo monocryl prolene composite (Johnson & Johnson-Ethicon). A los 28 días después del procedimiento quirúrgico se sacrificaron los biomodelos y se extrajeron las muestras que posteriormente fueron tratadas con técnicas histoquímicas para su análisis histológico. Resultados: El estudio reportó adherencia a omento en los dos tipos de malla utilizadas, sin embargo, la malla comercial mostró adherencias de amplio espesor a colon, intestino delgado e hígado, incluyendo también al omento menor. Se encontró que la malla comercial presentaba mayor cantidad de mastocitos en las regiones estudiadas (dermis, perimisio, y la serosa visceral). Discusión: Estudios refieren que los mastocitos y sus productos como la histamina, la serotonina, entre otras juegan un papel clave en el control de la inflamación local, la cicatrización de heridas, adherencias y las reacciones a cuerpos extraños in vivo. Conclusión: Con base en la literatura consultada se puede concluir que el presente estudio es vanguardista en lo que respecta al posible papel que juegan los mastocitos en el proceso de reparación de defectos anatómicos de la pared abdominal.


Objective: The objective of this study was to evalúate the role of mast cells in the postoperative inflammatory response after implantation of prosthetic mesh to repair abdominal wall defects in Wistar rat. Materials and Methods: An abdominal wall defect (30 × 20 mm) was created in the anterior abdominal wall of 25 adult male Wistar rats. The anatomical defect was then repaired with one of the two type's meshes. Fibroin and monocryl ultrapo prolene meshes. Fibroin meshes were manufactured by weaving its threads, the polypropylene mesh was bought to Johnson & Johnson-Ethicon. After 28 days of implantation Wistar rats were sacrificed and the mesh with abdominal tissue was extracted. Subsequently the samples were treated with histochemical techniques for histological analysis. Results: The study reported adherence to omentum in both types of meshes used, however, the polypropylene mesh showed widely adhesions to colon, slight to intestine and liver, also in a very lower amount, adhesions to omentum. It was found that mast cells were presented in all the studied regions for the polypropylene mesh (dermis, perimysium, and visceral serosa). Discussion: Studies indicate that mast cells and their products such as histamine, seroto- nin, and others play a key role in controlling local inflammation, wound healing, adhesions, and reactions to foreign bodies in vivo. Conclusion: We can conclude that this study is a good step to show the possible role of mast cells in the abdominal wall repair process.


Asunto(s)
Animales , Masculino , Ratas , Mallas Quirúrgicas , Pared Abdominal/cirugía , Mastocitos/metabolismo , Histamina/metabolismo , Serotonina/metabolismo , Ratas Wistar , Modelos Animales , Inflamación
4.
Rev. esp. investig. oftalmol ; 3(1): 36-39, ene.-mar. 2013. ilus
Artículo en Español | IBECS | ID: ibc-112466

RESUMEN

Caso clínico: Se presenta el caso de un varón mestizo de 33 años, con cuadro de conjuntivitis aguda purulenta en ojo izquierdo, lesión granulomatosa sobreelevada en el tercio externo de la conjuntiva tarsal y adenopatías preauricular y submandibular izquierdas. Se detectó serología IgM positiva para B. henselae. Se consiguió remisión completa con azitromicina oral y ciprofloxacino tópico. Conclusión: El síndrome oculoglandular de Parinaud (SOGP) es la manifestación ocular más frecuente de la enfermedad por arañazo de gato (EAG). La EAG debe considerarse entre los diagnósticos diferenciales ante cuadros de conjuntivitis unilateral asociada a adenopatías regionales (AU)


Case report: We report the case of a 33 year old mestizo male, with acute purulent conjunctivitis in his left eye, an elevated granulomatous lesion in the outer third of the tarsal conjunctiva and left preauricular and submandibular lymph nodes. IgM serology was positive for B. henselae. Complete remission was achieved with oral azithromycin and topical ciprofloxacin. Conclusion: Parinaud oculoglandular síndrome is the most common ocular manifestation of cat scratch disease (CSD). The CSD should be considered in the differential diagnosis in the case of unilateral conjunctivitis associated with regional lymphadenopathy (AU)


Asunto(s)
Humanos , Masculino , Adulto , Trastornos de la Motilidad Ocular/diagnóstico , Enfermedad por Rasguño de Gato/diagnóstico , Conjuntivitis Bacteriana/etiología , Granuloma/etiología , Azatioprina/uso terapéutico
5.
Angiología ; 63(6): 261-265, nov.-dic. 2011. tab, graf
Artículo en Español | IBECS | ID: ibc-97917

RESUMEN

Introducción: La infección de injerto vascular es una entidad que tiene alta mortalidad y morbilidad entre los pacientes con enfermedad arterial periférica sometidos a estos procedimientos. Debido a la poca información sobre el comportamiento de las infecciones de injerto vascular en nuestro medio, es importante identificar los factores de riesgo que se asocian a las infecciones de injerto protésico vascular en reconstrucciones infrainguinales. Métodos: Estudio retrospectivo de casos y controles en pacientes sometidos a reconstrucción infrainguinal en el Hospital Universitario San Vicente de Paúl, Medellín, con injerto protésico, tomando como caso a quienes desarrollan infección, y como control a quienes no, según la clasificación de Szilagyi. Resultados: Se obtuvo un total de 34 casos y 34 controles, con una tasa de infección en reconstrucción infrainguinal protésica del 25,75%. No hubo diferencias significativas en la distribución por sexo, edad y clasificación de ASA. La mayoría de los casos se clasificaron como Szilagyi II y III (19,5 y 23,5%). La mayoría de los diagnósticos de infección se realizaron en los primeros 30 días del postoperatorio, siendo los microorganismos más aislados S. aureus y E. Coli. Se constituyeron como factores de riesgo para el desarrollo de infecciones la presencia de complicaciones en la herida quirúrgica (OR: 77,5; IC: 93,4-99,73), reintervenciones (OR: 7,23; IC: 1,82 - 28,4), el hábito de fumar (OR: 4,04 IC: 1,37-11,86) y el tiempo operatorio (p=0,002; IC: 21,74-91,25). Variables como comorbilidades, tipo de injerto o cirugías concomitantes no tuvieron influencia sobre la aparición de infecciones en la población estudiada. Conclusión: Las complicaciones en la herida quirúrgica, las reintervenciones, el tiempo operatorio prolongado y el hábito de fumar se relacionan con un riesgo elevado de sufrir infección de injerto vascular en la población estudiada(AU)


Vascular graft infection has high mortality and morbidity among patients with peripheral arterial disease undergoing limb artery bypass. Due to there being little information available in Latin American centers on this complication, it is important to identify risk factors associated with infrainguinal prosthetic graft infections. Vascular graft infections are a serious complication, with reports of up to 17% mortality and a morbidity of 41%, the loss of the limb being the most frequent outcome (1).Although the incidence of vascular graft infection is reported to be from 1% to 6% in most series, some studies in Latin American centers show incidences between 4% and 11.6% Methods: A retrospective case-control study was conducted on patients undergoing infrainguinal reconstruction with prosthetic graft at the Hospital Universitario San Vicente Fundacion, Medellín, taking as case patients who developed an infection; and controls, patients who did not, according to the classification of Szilagyi. Results: A total of 34 cases and 34 controls, no differences in gender distribution or age, were obtained over a period of 10 years. The most frequently isolated microorganism was S. aureus, with a significant proportion of methicillin resistant S. aureus. The variables found to be associated with significant vascular graft infection in the bivariate analysis were, the presence of wound complications (OR: 77.7, 95% CI; 15.9 to 375, P=.000), re- interventions (OR 7.23, 95% CI; 1.84 to 28.40, P=.002), smoking (OR 4.04, 95% CI; 1.37 to 11.86, P=.009), surgical time greater than 75 percentile for the population studied (OR 6.61, 95% CI; 1.2 to 2.82, P=.012).Variables such as comorbidities, type of graft or concomitant surgery had no influence of the appearance of infections in the population studied(AU)


Conclusion: Surgical wound complications, re-interventions, longer operating time, and smoking are associated with an increased risk of suffering from a vascular graft infection in the population studied(AU)


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Factores de Riesgo , Injerto Vascular/efectos adversos , Injerto Vascular/métodos , Injerto Vascular/tendencias , Infección de la Herida Quirúrgica/complicaciones , Infección de la Herida Quirúrgica/diagnóstico , Infección de la Herida Quirúrgica/terapia , Staphylococcus aureus/aislamiento & purificación , Escherichia coli/aislamiento & purificación , Infecciones por Escherichia coli/complicaciones , Infección de la Herida Quirúrgica/fisiopatología , Indicadores de Morbimortalidad , Estudios Retrospectivos , Profilaxis Antibiótica/métodos , Profilaxis Antibiótica
6.
Public Health Rep ; 116(6): 520-9, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-12196611

RESUMEN

Funding from the Centers for Disease Control and Prevention and the Health Resources and Services Administration (HRSA) supports collaborations among health departments (CA, FL, GA, IL, MA, NJ, NY), correctional facilities, and community-based organizations to improve services to HIV-infected inmates, particularly as they return to the community. Additionally, HRSA funded the Evaluation and Program Support Center to guide the implementation of a multi-site evaluation of the Corrections Demonstration Project (CDP). The authors present a model approach to the problem of health disparities that involves forging collaborations among federal funders, public health departments, corrections, community-based organizations, and the scientific research community. They show how such collaboration can promote the reduction of racial/ethnic health disparities. The authors examined disease screening activities in five county jails. Screening for HIV and other sexually transmitted infections (STIs) was offered during the medical intake process and during HIV prevention education sessions. One thousand twenty inmates were tested from July 1, 2000, through December 31, 2000, for HIV infection, and 171 (17%) positive cases were identified (largely due to confirmatory testing). Of HIV-positive inmates, 83 (49%) were started on antiretroviral treatment. Additionally, 2,160 were tested for chlamydia, 1,327 for gonorrhea (largely duplicated), and 937 (duplicated) for syphilis. Across all three STIs, 78% of those who tested positive were treated. The remaining 22% either declined treatment, were released prior to notification of results, or were released prior to starting treatment. The CDP offers a model approach for addressing the poor health status of members of racial/ethnic minority groups by developing collaborations between corrections, public health departments, community-based organizations, and academia. An outgrowth of this collaboration is the improved capacity to detect and treat disease, which is a necessary component of a comprehensive HIV risk reduction program.


Asunto(s)
Relaciones Comunidad-Institución , Conducta Cooperativa , Infecciones por VIH/diagnóstico , Accesibilidad a los Servicios de Salud/organización & administración , Tamizaje Masivo/organización & administración , Modelos Organizacionales , Prisioneros , Prisiones/organización & administración , Administración en Salud Pública , Enfermedades de Transmisión Sexual/diagnóstico , Serodiagnóstico del SIDA , Centers for Disease Control and Prevention, U.S. , Atención Integral de Salud/economía , Atención Integral de Salud/organización & administración , Femenino , Financiación Gubernamental , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Accesibilidad a los Servicios de Salud/economía , Humanos , Gobierno Local , Masculino , Tamizaje Masivo/economía , Proyectos Piloto , Prisiones/economía , Enfermedades de Transmisión Sexual/tratamiento farmacológico , Enfermedades de Transmisión Sexual/epidemiología , Enfermedades de Transmisión Sexual/prevención & control , Factores Socioeconómicos , Estados Unidos/epidemiología , United States Health Resources and Services Administration
7.
Contraception ; 61(5): 309-16, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10906501

RESUMEN

A phase III clinical study was carried out among 534 fertile Latin American women to evaluate cycle control, side effects, and contraceptive efficacy of a once-a-month combined injectable, Mesigyna, consisting of 50 mg norethisterone enanthate and 5 mg estradiol valerate. The pregnancy rate at 1 year was 0 per 100 woman-years for a total experience of 4688 woman-months. The overall discontinuation rate at one year was 17.9%. Discontinuation rate for bleeding problems was 5.1%. The Colombian women had a significant increase (p <0.001) in bleeding problems compared to other countries. The discontinuation rate for amenorrhea was 1.1%. There were no significant differences between the groups regarding discontinuation for other medical or non-medical reasons. Mean weight gain after one year of use was 1.02 kg. Mesigyna is an appropiate once-a-month injectable contraceptive for Latin American women since it is highly effective and its perception of normal menstrual bleeding is of importance in the Latin American population.


Asunto(s)
Anticonceptivos Femeninos , Estradiol/análogos & derivados , Noretindrona/análogos & derivados , Adolescente , Adulto , Amenorrea/inducido químicamente , Presión Sanguínea , Anticonceptivos Femeninos/administración & dosificación , Anticonceptivos Femeninos/efectos adversos , Combinación de Medicamentos , Femenino , Humanos , Inyecciones , América Latina , Embarazo , Hemorragia Uterina/inducido químicamente , Aumento de Peso
8.
GMHC Treat Issues ; 12(6): 7-8, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11365724

RESUMEN

AIDS: Community-based organizations are involved in a program to recycle HIV drugs to patients in developing countries. Unused drugs from patients who have died or who have switched to other medications are donated to organizations which distribute them outside the United States. Initially, the program mostly provided drugs for opportunistic infections, but the scope of the program has expanded to include protease inhibitors and other drugs. A number of ethical and health care issues are involved, including the issue of treatment continuity.^ieng


Asunto(s)
Fármacos Anti-VIH/provisión & distribución , Países en Desarrollo , Infecciones por VIH/tratamiento farmacológico , Fármacos Anti-VIH/economía , Fármacos Anti-VIH/uso terapéutico , Femenino , Infecciones por VIH/prevención & control , Accesibilidad a los Servicios de Salud , Necesidades y Demandas de Servicios de Salud , Humanos , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Masculino , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Zidovudina/economía , Zidovudina/provisión & distribución , Zidovudina/uso terapéutico
9.
Sidahora ; : 32-7, 1997.
Artículo en Español | MEDLINE | ID: mdl-11364828

RESUMEN

AIDS: Recommendations are provided to determine what guidelines to use to treat HIV patients. Principles such as fast progression of the virus, T-cell count, individual treatments, and combinations of drugs and therapies are discussed in detail. The recommendations include the use of laboratory tests for T-cell count, when and which treatment to initiate, types of therapy to use for advanced HIV infection, when to stop the treatment and when to change treatments. A table gives information on initial anti-retroviral therapy and several combinations of drugs, from the preferred to the least recommended, are presented. A detailed report on how to approach the disease and its treatment is included.^ieng


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Recuento de Linfocito CD4 , Humanos , Guías de Práctica Clínica como Asunto
10.
GMHC Treat Issues ; 11(7-8): 31-2, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-11364651

RESUMEN

AIDS: Although treatment recommendations for pregnant HIV-positive women are addressed in Federal guidelines, there are no firmly-defined answers to when treatment should begin and how the existing drugs should be used. There is a lack of research on the safety and efficacy of the available drugs, with the exception of AZT, 3TC, and nevirapine. Pregnant women do not have enough scientific information available to make an informed decision. The Food and Drug Administration (FDA) classify drugs based on clinical data relevant to their use in pregnancy; that table is included. Some treatment-naive patients are counseled to delay therapy until after 10 to 12 weeks of gestation, but after that point, treatment should continue.^ieng


Asunto(s)
Infecciones por VIH/tratamiento farmacológico , Guías de Práctica Clínica como Asunto , Complicaciones Infecciosas del Embarazo/tratamiento farmacológico , Femenino , Infecciones por VIH/transmisión , Humanos , Embarazo , Factores de Riesgo , Estados Unidos
11.
Sidahora ; : 8-13, 1997.
Artículo en Español | MEDLINE | ID: mdl-11364503

RESUMEN

AIDS: Visual manifestations of HIV infection and AIDS can present in a variety of ways. Different types of ocular infections are classified and factors that affect diagnosis and treatment are explained. Complications to the eyelids and anterior and posterior parts of the eye are addressed. Steps to determine the presence of ophthalmic herpes, Kaposi's sarcoma (KS), syphilis, conjunctivitis, and CMV retinitis are given. Cytomegalovirus and toxoplasmosis infections, and diseases that effect the retina and cause blindness are discussed.^ieng


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/complicaciones , Infecciones del Ojo/complicaciones , Infecciones por VIH/complicaciones , Trastornos de la Visión/complicaciones , Infecciones Oportunistas Relacionadas con el SIDA/complicaciones , Infecciones por Citomegalovirus/complicaciones , Infecciones por Herpesviridae/complicaciones , Humanos , Sífilis/complicaciones , Toxoplasmosis/complicaciones
12.
Sidahora ; : 14-7, 1997.
Artículo en Español | MEDLINE | ID: mdl-11364489

RESUMEN

AIDS: The Fourth Conference on Retroviruses and Opportunistic Infections was held in Washington, D.C. in January 1997. Topics that were presented at the conference include reduced AIDS mortalities in New York, reduced hospitalizations for opportunistic infections, clinical advances in antiretroviral therapies, and treatment and prevention of opportunistic infections. Drug therapies, viral load change, T4 cell counts, and peripheral neurodegeneration are discussed. Special attention is given to combination therapies.^ieng


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , Infecciones Oportunistas Relacionadas con el SIDA/prevención & control , Infecciones Oportunistas Relacionadas con el SIDA/terapia , Síndrome de Inmunodeficiencia Adquirida/complicaciones , Síndrome de Inmunodeficiencia Adquirida/tratamiento farmacológico , Síndrome de Inmunodeficiencia Adquirida/mortalidad , Fármacos Anti-VIH/administración & dosificación , Fármacos Anti-VIH/uso terapéutico , Recuento de Linfocito CD4 , Farmacorresistencia Microbiana , Quimioterapia Combinada , Financiación Gubernamental , VIH-1/genética , VIH-1/aislamiento & purificación , Humanos , Mutación , New York , Enfermedades del Sistema Nervioso Periférico , Carga Viral
13.
Sidahora ; : 34-5, 1997.
Artículo en Español | MEDLINE | ID: mdl-11364805

RESUMEN

AIDS: Wasting syndrome is a condition in which there is an unexplained loss of weight (about ten percent of normal weight). The differences between losing weight due to an opportunistic infection and losing weight for unexplained reasons are reviewed. Some listed reasons include oral pain that prevents eating, an improperly working digestive system, and the body's inability to absorb nutrients. Colonoscopy and stool analysis can detect these conditions. Ways to prevent wasting disorder are presented, including the use of hormones.^ieng


Asunto(s)
Síndrome de Emaciación por VIH/fisiopatología , Colonoscopía , Sistema Digestivo/fisiopatología , Ingestión de Alimentos , Heces , Síndrome de Emaciación por VIH/prevención & control , Hormonas/uso terapéutico , Humanos , Dolor , Pérdida de Peso
14.
Sidahora ; : 12-4, 1997.
Artículo en Español | MEDLINE | ID: mdl-11364947

RESUMEN

AIDS: Although the United States Public Health Service has recommended guidelines for the use of antiretrovirals during pregnancy, the treatments for HIV-positive pregnant women are still inconclusive. Contradictions within the guidelines are explained. The Food and Drug Administration's (FDAs) treatment study classifications and results for HIV-positive women are listed. Fetal risk, animal studies, treatments using protease inhibitors and/or reverse transcriptase inhibitors, and the effect of starting treatment during different trimesters are discussed. Recommendations for when to begin treatment are provided.^ieng


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Inhibidores de la Proteasa del VIH/uso terapéutico , Complicaciones Infecciosas del Embarazo , Inhibidores de la Transcriptasa Inversa/uso terapéutico , Fármacos Anti-VIH/efectos adversos , Contraindicaciones , Femenino , Feto/efectos de los fármacos , Inhibidores de la Proteasa del VIH/efectos adversos , Humanos , Guías de Práctica Clínica como Asunto , Embarazo , Inhibidores de la Transcriptasa Inversa/efectos adversos
15.
Dev Biol ; 125(1): 217-25, 1988 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3119401

RESUMEN

Enriched populations of guinea pig spermatogenic cells were isolated by sedimentation velocity at unit gravity. Each cell population was analyzed for the presence of members of the proacrosin/acrosin family by enzymography, immunoblotting, and immunofluorescence. Following sodium dodecyl sulfate-polyacrylamide gel electrophoresis in gels containing 0.1% gelatin, protease activities with molecular weights of 55,000 (major) and 50,000 (minor) were detected in round spermatid extracts. Condensing spermatid extracts contained protease activities with molecular weights between 55,000 and 50,000. These major protease activities had molecular weights similar to antigens detected by immunoblotting with a monospecific rabbit antiserum directed against purified boar acrosin. Extracts of guinea pig sperm and the soluble acrosomal components released following the acrosome reaction induced with ionophore A23187 contained three major protease activities (Mr 32,000, 34,000, 47,000) but only the 47,000 Mr protease cross-reacted with the antibody. The spermatid and sperm protease activities were inhibited and activated by classical effectors of acrosin activity from other species. Immunofluorescence demonstrated that proacrosin/acrosin was present as early as the Golgi phase of spermiogenesis. In addition, immunoreactivity was confined to the acrosomes in a manner characteristic of each spermatid stage. These results demonstrate that proacrosin/acrosin can be detected in the earliest spermiogenic stages by electrophoretic and immunological techniques and suggest that changes in the molecular weights of proacrosin/acrosin occur as spermatids mature.


Asunto(s)
Acrosina/biosíntesis , Precursores Enzimáticos/biosíntesis , Serina Endopeptidasas/biosíntesis , Espermatogénesis , Acrosoma/análisis , Animales , Reacciones Cruzadas , Técnica del Anticuerpo Fluorescente , Cobayas , Yodoacetatos/farmacología , Ácido Yodoacético , Masculino , Péptido Hidrolasas/metabolismo , Espermátides/análisis
16.
J Exp Zool ; 244(2): 277-87, 1987 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3323410

RESUMEN

The major proteases associated with guinea pig sperm were investigated by using immunological and electrophoretic techniques. Three major proteases were detected following sodium dodecyl sulfate-polyacryl-amide gel electrophoresis in gels containing 0.1% gelatin. These enzymes had molecular weights of 47,000, 34,000, and 32,000 relative to reduced protein standards and 58,500, 40,000, and 37,500 relative to unreduced standards. All three protease activities were present in acid extracts of sperm, detergent extracts of sperm, and the soluble acrosomal components of sperm released following induction of the acrosome reaction with the Ca2+-ionophore A23187. As determined by indirect immunofluorescence, an antibody to purified boar acrosin specifically cross-reacted with the acrosomes of guinea pig sperm. Decreased fluorescence was associated with sperm that had lost their acrosomes. Immunoblot analysis demonstrated that this antibody reacted with the 47,000 Mr protease but not the 32,000 and 34,000 Mr proteases. All three proteases were maximally active in the pH 7.0-8.5 region and were inhibited by classical inhibitors of acrosin activity. During a 3-hour incubation period, MgCl2 (10 mM) inhibited the activities of the 32,000 and 34,000 Mr proteases while the 47,000 Mr protease was stimulated. Although these proteases shared properties that would classify them as trypsin-like proteases, only the 47,000 Mr protease could be definitely classified as a member of the proacrosin-acrosin family based upon cross-reaction with an antibody to purified boar acrosin.


Asunto(s)
Acrosoma/enzimología , Péptido Hidrolasas/análisis , Espermatozoides/enzimología , Acrosina/análisis , Animales , Cloruro de Calcio/farmacología , Reacciones Cruzadas , Electroforesis en Gel de Poliacrilamida , Técnica del Anticuerpo Fluorescente , Cobayas , Concentración de Iones de Hidrógeno , Inmunoensayo , Magnesio/farmacología , Cloruro de Magnesio , Masculino , Peso Molecular , Inhibidores de Proteasas/farmacología
17.
J Biol Chem ; 262(23): 10903-6, 1987 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-3301845

RESUMEN

Cultured human cytotrophoblasts synthesize and secrete urokinase-type plasminogen activator (uPA) during the first 24 h of culture, but secretion declines during the subsequent day. In contrast, synthesis and secretion of fibronectin increases during the 2 days of culture. The levels of uPA mRNA parallel the changes in synthesis and secretion of uPA. Treatment of cytotrophoblasts with 8-bromo-cAMP (1.5 mM) transiently raises uPA mRNA levels and uPA secretion. This treatment reduces fibronectin mRNA levels and causes a sustained increase in beta chorionic gonadotropin mRNA content and chorionic gonadotropin secretion. We conclude that a cAMP-mediated process up-regulates uPA expression in cytotrophoblasts. However, the stimulatory effect of the cyclic nucleotide analog on uPA is transient.


Asunto(s)
Trofoblastos/enzimología , Activador de Plasminógeno de Tipo Uroquinasa/biosíntesis , 8-Bromo Monofosfato de Adenosina Cíclica/farmacología , Células Cultivadas , Fibronectinas/biosíntesis , Fibronectinas/metabolismo , Técnicas de Inmunoadsorción , Cinética , ARN Mensajero/metabolismo , Trofoblastos/efectos de los fármacos , Activador de Plasminógeno de Tipo Uroquinasa/metabolismo
18.
Biol Reprod ; 37(1): 201-10, 1987 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3477294

RESUMEN

Guinea pig (GP) acrosin was purified following acid extraction of testicular acetone powder, pH precipitation of the soluble extract, gel filtration on Sephadex G-100, ion-exchange chromatography on SP-Sephadex, and affinity chromatography on Concanavalin A-Sepharose. Final purification was achieved by re-chromatography on Sephadex G-100. Enzymatic activity was detected by following the hydrolysis of N-benzyloxycarbonylarginyl amide of 7-amino-4-trifluoromethylcoumarin at 37 degrees C, pH 8.0, before and after activation. GP testicular acrosin exhibited a molecular weight of 48,000 by gel filtration and 34,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Following SDS-PAGE in gels containing 0.1% gelatin, protease activity was observed to comigrate with the major protein detected by silver staining. The purified GP acrosin showed cross-reactivity with a monospecific polyclonal rabbit antiserum directed against boar sperm acrosin and exhibited reversible pH-dependent activation. The physiochemical characteristics of the purified protein, including the amino acid composition, resemble those reported for acrosins from other species.


Asunto(s)
Acrosina/aislamiento & purificación , Serina Endopeptidasas/aislamiento & purificación , Testículo/análisis , Aminoácidos/análisis , Animales , Cromatografía en Gel , Electroforesis en Gel de Poliacrilamida , Cobayas , Masculino , Peso Molecular
19.
Arch Gen Psychiatry ; 42(10): 1004-13, 1985 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-4037984

RESUMEN

The Thought Disorder Index, which has been shown to be a reliable and valid measure of the degree of thought disorder in adult psychotic patients, was used to assess thought disorder in children. Normal children aged 5 to 16 years, hospitalized psychotic children, children hospitalized for nonpsychotic behavioral problems, and children born to a psychotic mother (high-risk) were tested. In the normal sample, thought disorder decreases with age. The level of thought disorder in psychotic children and high-risk children was about three times higher than that of the normal children, whereas the level of thought disorder of the nonpsychotic hospitalized children was no different from that of the normal children. The study also detected differences in the kinds of thought disorder that characterize the psychotic and high-risk groups vs the other children. The presence of thought disorder may be thought of as a useful indicator of the diathesis for functional psychosis. The Thought Disorder Index merits selection as a tool for investigating thought disorder as a potential precursor variable in studies of children at risk for schizophrenia and manic-depressive illness.


Asunto(s)
Trastornos del Conocimiento/diagnóstico , Trastornos Psicóticos/psicología , Pensamiento , Adolescente , Adulto , Factores de Edad , Trastorno Bipolar/diagnóstico , Trastorno Bipolar/genética , Trastorno Bipolar/psicología , Niño , Desarrollo Infantil , Preescolar , Trastornos del Conocimiento/psicología , Femenino , Hospitalización , Humanos , Pruebas de Inteligencia , Masculino , Escalas de Valoración Psiquiátrica , Trastornos Psicóticos/diagnóstico , Trastornos Psicóticos/genética , Riesgo , Prueba de Rorschach , Esquizofrenia/diagnóstico , Esquizofrenia/genética , Psicología del Esquizofrénico , Conducta Verbal
20.
Theor Appl Genet ; 48(2): 67-73, 1976 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24413653

RESUMEN

Selection indexes to maximize net income for egg laying chickens were constructed with information on egg mass output, body weight and individual feed records. Relative selection efficiencies were then compared with different kinds of information in the index. If the genetic variation in feed consumption is completely determined by egg mass output (M) and body weight (W), using reliable estimates of genetic correlations or pehnotypic regressions of these traits with feed consumption in the index is equally efficient to an index with individual feed records. If real genetic differences in feed efficiency exist which are independent of egg mass and body weight, (h u (2) ), then there is greater justification in using individual feed consumption records. Forexample, if h u (2) =0.2, h W (2) =0.6, h M (2) =0.15 and rGWM (genetic correlation)=0.2, the use of individual feed records is expected to improve efficiency of the selection for net income by 9 p. On the other hand, if the genetic correlations of feed consumption on body weight and on egg mass are substituted in the index for records on individual feed consumption, only slightly less selection efficiency would result.

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