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1.
Rev. chil. neuro-psiquiatr ; 57(2): 167-175, jun. 2019. tab
Article in Spanish | LILACS | ID: biblio-1042686

ABSTRACT

Resumen El objetivo del presente estudio fue determinar la estructura factorial y las características psicométricas de la Escala de Desesperanza de Beck (BHS), validando su utilización en Chile como instrumento útil para la pesquisa de riesgo suicida en jóvenes universitarios. Método: La muestra estuvo compuesta por 200 estudiantes de primer año de la Universidad Austral de Chile, quienes respondieron voluntariamente el consentimiento informado, la BHS y los otros cuestionarios que permitieron verificar la validez concurrente y discriminante de la escala. Se realizaron análisis de consistencia interna, correlacionales y de componentes principales. Resultados: Los distintos procedimientos de análisis permiten sostener que la escala BHS es un instrumento confiable y valido para detectar riesgo de suicidio en población universitaria chilena. Asimismo, los análisis arrojaron un modelo de cuatro factores, el que varía de lo propuesto por los autores de la BHS, aunque es concordante con lo encontrado en otros estudios internacionales. Conclusiones: La presente investigación permite suponer que la BHS es un instrumento confiable y válido para detectar riesgo suicida en estudiantes universitarios chilenos. Este instrumento breve y fácil de administrar permitiría detectar eficaz y tempranamente suicidalidad, siendo un aporte a la prevención de este fenómeno en nuestro país.


Introduction: The aim of present study is to determine the psychometric properties and the factorial structure of the Beck Hopelessness Scale (BHS), validating its use in Chile as a suicide risk screening tool among university students. Method: The sample included 200 college freshmen undergraduate belonging to the Austral University of Chile, who through the website of the university, answered voluntary the Informed Consent and the questionnaires that allowed verifying the concurrent and discriminant validity of the BHS scale. The internal consistency of this scale was evaluated by Cronbach's alpha internal consistency. The data were analyzed through correlational and principal component analyzes. Results: The different Statistical analysis revealed a high level of internal consistency in the BHS scale, being a reliability and valid instrument to detect suicide risk in Chilean university population. Likewise, Principal Component Analysis showed a four-factor model, which varies from that proposed by the BHS authors, although it is consistent with that found in other international studies. Conclusions: The present investigation allows us to suppose that the BHS is a reliable and valid instrument to detect suicidal risk in Chilean university students. This brief and easy to administer instrument would allow to detect effective and early suicidality, being a contribution to the prevention of this phenomenon in our country.


Subject(s)
Humans , Male , Female , Psychometrics , Students , Suicide , Universities , Risk , Chile , Surveys and Questionnaires
2.
Rev. chil. neuro-psiquiatr ; 52(3): 167-176, set. 2014. graf, tab
Article in Spanish | LILACS | ID: lil-726145

ABSTRACT

Introduction: In our country Chile it is estimated that approximately a third of the population would have had some psychiatric disorder during its life. Ifwe consider the university population, the evolutionary stage that it experiences and the psychosocial stress that affect them, we observe a group at risk to present psychiatric disorders. The aim of the present study was to estimate the prevalence of the principal mental disorders not psychotic in the population of students of the UACH, during the year 2008. Material and Method: The sample consisted of 804 undergraduate students, that answered individually the Patient Health Questionnaire (PHQ-9), the Scale of Beck's hopelessness (HBS), the Mood Disorder Questionnaire (MDQ), the Questionnaire of detection of problematic consumption of alcohol and drugs in teenagers (DEP-ADO), the questionnaire AUDIT, the Eating Disorder Diagnostic Scale (EDDS) and the Restrain Scale (RE). Results: 27% of the students fulfills with criteria for a depression, 10,4% deals with a bipolar disorder, 5,3% has a moderated risk to severe of committing suicide, 24,2% of the students presents a problematic consumption to alcohol and 15,3% it would have some type of disorder in his supplies when eating. Conclusions: Depression was significantly associated with a greater tendency to have abnormal eating behavior, harmful alcohol consumption and self-destructive behavior.


Introducción: Se estima que en Chile aproximadamente un tercio de la población ha tenido algún trastorno psiquiátrico durante su vida. Si tenemos en cuenta a la población universitaria, por la etapa evolutiva que experimenta y el estrés psicosocial asociado, ésta se constituye como un grupo en riesgo de presentar trastornos psiquiátricos. El presente estudio se propuso estimar la prevalencia de los principales trastornos mentales no psicóticos presentes en la población de estudiantes depregrado de la UACh, durante el año 2008. Método: La muestra estuvo compuesta por 804 estudiantes de pregrado, que respondieron de manera individual escalas de screening para la depresión (Patient Health Questionnaire-PHQ-9), para el riesgo de suicidio (Escala de desesperanza de Beck-HBS), para los trastornos bipolares (Mood Disorder Questionnaire-MDQ), para el consumo de alcohol y drogas (DEP-ADO y AUDIT), y para los trastornos de la conducta alimentaria (Eating Disorder Diagnostic Scale-EDDS; y Restrain Scale-RS). Resultados: Un 27% de los estudiantes cumple con los criterios diagnósticos para una depresión, un 10,4% estaría cursando con un trastorno bipolar, un 5,3% de los estudiantes tiene un riesgo moderado a severo de cometer suicidio; 24,2% de los estudiantes universitarios presenta un consumo problemático de alcohol y un 15,3% de la muestra tendría algún tipo de trastorno en la alimentación. Conclusiones: La depresión se asoció significativamente con una mayor tendencia a tener un comportamiento de alimentación anormal, el consumo nocivo de alcohol y el comportamiento autodestructivo.


Subject(s)
Humans , Male , Female , Students , Mental Health , Risk Factors , Mental Disorders , Universities , Epidemiology, Descriptive
3.
Rev. chil. neuro-psiquiatr ; 50(1): 10-22, mar. 2012. ilus, tab
Article in Spanish | LILACS | ID: lil-627277

ABSTRACT

Background: Depressive disorders (TD) is a set of prevalent diseases that require proper diagnosis and treatment. In Chile, the instruments of evaluation and diagnosis are scarce. As a way to address this difficulty, the objective of this study was to validate the Spanish version of the self-reported Patient Health Questionarie (PHQ-9), the consulting population in primary care in Chile. The PHQ-9 to detect depressive symptoms as mild, moderate or severe, and has proven to be an efficient diagnostic tool. Methods: 1327 patients evaluated in June 2005 from five urban general practices of the Commune of Valdivia answered individually the PHQ-9. A subsample was compared with the Hamilton scale for depression, ICD-10 criteria for depression and XX version of the PHQ-9. Results: The PHQ-9 demonstrated a sensitivity of 92 percent and 89 percent specificity in detecting depressive patients, when compared to the Hamilton-D scale. It presents a construct validity and predictive validity concurrent with the ICD-10 criteria for depression. Conclusions: The PHQ-9 showed a psychometric allowing clinical use in primary care patients in Chile.


Introducción: Los trastornos depresivos (TD) son un conjunto de enfermedades prevalentes que requieren de un adecuado diagnóstico y tratamiento. En Chile, los instrumentos de evaluación y diagnóstico son escasos. Como forma de enfrentar esta dificultad, el objetivo del presente estudio fue validar la versión en español del auto-reporte Patient Health Questionarie (PHQ-9), en la población consultante de la atención primaria en Chile. El PHQ-9 permite detectar sintomatología depresiva leve, moderada o severa, y ha demostrado ser un eficiente instrumento de diagnóstico. Material y Método: 1.327 pacientes evaluados en junio 2005, provenientes de 5 consultorios generales urbanos de la Comuna de Valdivia respondieron individualmente el PHQ-9. Una sub-muestra fue comparada con la escala de Hamilton para depresión, los criterios CIE-10 para depresión y la versión XX del PHQ-9. Resultados: El PHQ-9 demuestra una sensibilidad de un 92 por ciento y especificidad de 89 por ciento en la detección de pacientes depresivos, al compararla con la escala de Hamilton-D. Además, presenta una validez de constructo y una validez predictiva concurrente con los criterios de CIE-10 para depresión. Conclusiones: El PHQ-9 mostró un comportamiento psicométrico que permite su utilización clínica en pacientes de atención primaria en Chile.


Subject(s)
Humans , Male , Female , Adult , Primary Health Care , Surveys and Questionnaires , Depressive Disorder/diagnosis , Chile , Predictive Value of Tests , Psychometrics , Reproducibility of Results , Sensitivity and Specificity , Urban Area
4.
Rev. Méd. Clín. Condes ; 22(3): 303-309, mayo 2011. graf, ilus
Article in Spanish | LILACS | ID: lil-600329

ABSTRACT

Las conductas suicidas son un problema de Salud Pública en Chile y en el mundo, dentro de ellas se incluyen el intento de suicidio y el suicidio. En este artículo se realizará una revisión general del problema en Chile, pero se centrará en la conducta clínica y de intervención en crisis. Es necesario realizar un diagnóstico adecuado de la conducta suicida, el cual debe basarse en la evaluación de cinco aspectos principales, según el modelo sugerido por la Escuela de Medicina de Harvard, el cual es detallado en el presente artículo. Finalmente, debemos tener presente que el eje central del enfrentamiento de un paciente evaluado por intento de suicidio es la intervención en crisis, la cual debe ser realizada por el primer médico que tenga contacto con el paciente.


Suicidal behavior is a public health problem in Chile and the world which include suicide attempts and suicides. This article will perform a general review of the problem in Chile, but will focus on the clinical behavior and crisis intervention. It is necessary to make a proper diagnosis of suicidal behavior, which should be based on the assessment of 5 main aspects, according to the model proposed by the Harvard Medical School, which is detailed in this article. Finally, we note that the central axis of the confrontation of a patient evaluated for attempted suicide is the crisis intervention, which must be performed by the first doctor who has contact with the patient.


Subject(s)
Humans , Crisis Intervention , Suicide, Attempted/prevention & control , Chile
5.
Rev. chil. neuro-psiquiatr ; 49(3): 273-282, 2011. ilus
Article in Spanish | LILACS | ID: lil-608780

ABSTRACT

Introducción: El suicidio constituye un problema de salud pública importante pero en gran medida prevenible. En Chile, según la OMS, el año 2003 hubo una tasa de suicidio de 10,4 por 100.000 habitantes con tendencia creciente. Objetivos: Analizar las tasas de suicidio y sus características sociodemográficas en la región de Los Ríos, años 1996-2008. Material y Métodos: Revisión de Protocolos de Autopsia del Servicio Médico Legal de Valdivia, años 1996-2008, ingresando los "casos de suicidio" a una pauta preestablecida. El análisis estadístico se realizó mediante el programa Microsoft Excel 2007y PASW Statistics v17.0. Las tasas fueron analizadas a través de la prueba de diferencias de proporciones y las demás variables fueron comparadas con la prueba Ji cuadrado. Resultados: Hubo 498 suicidios en el período estudiado. Las tasas de suicidio mostraron un aumento progresivo, llegando a 17,2 el 2005. Respecto al género, 413 muertes fueron hombres (82,9 por ciento) y 85 mujeres (17,1 por ciento). La razón hombre/mujer fue de 4,86/1. El 72,8 por ciento eran solteros o viudos y 27,2 por ciento casados o convivientes (p < 0,001). Destacan los rangos etarios 20-34 y 40-49 (p < 0,001). Las mujeres se suicidaron con más frecuencia que los hombres en edades tempranas, situación que se invirtió en edades mayores. El 21,7 por ciento estaban desempleados y el 78,3 por ciento empleados (p < 0,001). La mayoría de los suicidios se producen en: domicilio, horario diurno, por ahorcamiento (p < 0,001), sin asociación a alcohol significativa. Conclusión: El aumento registrado sobrepasa las tasas nacionales. La tendencia se correlaciona con otras publicaciones; difiriendo la situación de empleo y la asociación a alcohol al momento del suicidio. Las cifras obligan a una mayor responsabilidad en su reducción y prevención.


Introduction: Suicide is an important public health problem but largely preventable. In Chile, according to the WHO, in 2003 there was a suicide rate of 10,4 per 100.000 inhabitants with a growing tendency. Objectives: To analyze suicide rates and their sociodemographic features in Los Rios region from 1996-2008. Material and Methods: Autopsy protocols belonging to Valdivia Legal Medical Service, from 1996 to 2008, were reviewed and entered the "suicide cases" to a predetermined pattern. We performed statistical analysis through Microsoft Excel 2007 and PASW Statistics v17.0 programs. Rates were analyzed with the test for difference between proportions and the rest of variables were compared using chisquare test. Results: There were 498 suicides during the studied period. Suicide rates showed a progressive increase, even reaching to 17,2 by 2005. According to gender, 413 deaths were men (82,9 percent) and 85 women (17,1 percent); the male/female ratio was 4,86/1. 58,16 percent were single or widow(er), and 41,84 percent were married or cohabitants (p < 0,001). The age ranged between 20-34 and 40-49 were prominent (p < 0.001). Women committed suicide more often than men at young ages, a situation which was reversed at older ages. 22,1 percent were unemployed and 77,9 percent employed (p < 0.001). Most suicides occurs at home, during daytime, by hanging (p < 0.001) without significant association with alcohol. Conclusions: The reported increase exceeded the national rates. The tendency is correlated to other publications; this is different in the employed status and the association of alcohol at the time of suicide. The numbers oblige further responsibility in their decrease and prevention.


Subject(s)
Humans , Male , Female , Autopsy , Cause of Death , Suicide/statistics & numerical data , Suicide/trends , Age and Sex Distribution , Age Factors , Alcohol Drinking , Cross-Sectional Studies , Chile/epidemiology , Employment , Forensic Medicine , Marital Status , Prevalence , Seasons , Sex Factors , Socioeconomic Factors
6.
Rozhl Chir ; 89(4): 231-3, 2010 Apr.
Article in Czech | MEDLINE | ID: mdl-20586158

ABSTRACT

Currently, peroperative palpatory examination of the lungs represents standard method, however the development of the new mini-invasive surgery techniques devoid of palpable facilities, demands utilization of different procedures. The authors present their experiences involving detection of pulmonary lesions during thoracoscopic surgery visually, by endoscopic instruments, preoperative dye marking and peroperative ultrasonography via an endoscopic ultrasonic probe (all performed in Liberec District Hospital a.s.). The article describes operation techniques and tactics of thoracoscopic surgeries performed with pulmonary pathological processes in both subpleural and pulmonary parenchyma locations.


Subject(s)
Lung Diseases/diagnosis , Thoracoscopy/methods , Humans , Lung Diseases/surgery , Minimally Invasive Surgical Procedures , Palpation
7.
Rozhl Chir ; 89(10): 638-41, 2010 Oct.
Article in Czech | MEDLINE | ID: mdl-21374949

ABSTRACT

The diaphragm is the main respiratory muscle. It has the most significant function in respiratory excursions and the ability to maintain the negative thoracic pressure. Diaphragm injuries are relatively rare and they are the result of blunt or, in our conditions less often, penetrating thoracoabdominal trauma. (The ratio of blunt traumas to penetrating ones is 9:1). The diaphragmatic injuries in blunt injuries occur as a result of the increased pressure gradient between the pleural and peritoneal cavity [1]. The first description of traumatic diaphragm rupture is ascribed to Sennertus from 1541. Other sources award the primacy to the French royal surgeon A. Pare in 1579 [2]. It is similar to the primacy of the surgical repair of diaphragmatic injuries. Rioffi in 1886 [3] versus Naumann in 1888 who operated on traumatic herniation of the stomach into the left chest cavity [2]. Diaphragmatic injury diagnosis is difficult even today [4]; up to 10-50% of cases are not recognized in time. Left-sided traumatic lesion of the diaphragm occurs in 80-90% of cases. Our paper focuses on the specifics of right-sided diaphragm ruptures where the protective ability of the liver is probably reflected.


Subject(s)
Diaphragm/injuries , Abdominal Injuries/complications , Diaphragm/surgery , Humans , Rupture , Thoracic Injuries/complications , Wounds, Nonpenetrating/complications , Wounds, Nonpenetrating/diagnosis
8.
Rozhl Chir ; 87(10): 542-5, 2008 Oct.
Article in Czech | MEDLINE | ID: mdl-19110949

ABSTRACT

The authors bring their first experience with a purely endoscopic anatomical lung resection - lobectomy with mediastinal lymphadenectomy. At the department of surgery, Liberec Hospital, we have, so far, done 5 operations using this new technique. Once left superior lobectomy and 4 left inferior lobectomies were carried out. We describe the procedures and surgical tactics in thoracoscopic operations using modern staplers and haemoclips. The aim was to compare the results and benefits of purely endoscopic versus "classical" operations and to dismantle the myth of the extreme finacial intensiveness of this procedure.


Subject(s)
Pneumonectomy/methods , Thoracoscopy/methods , Aged , Female , Humans , Lung Neoplasms/surgery , Male , Middle Aged
9.
Pharmacogenomics J ; 4(2): 110-3, 2004.
Article in English | MEDLINE | ID: mdl-14708000

ABSTRACT

Synaptic vesicle proteins (SVP) play a critical role in neurotransmitter release and neural plasticity, and have been implicated in the pathophysiology of psychiatric disorders such as depression. Antidepressant drugs not only alter the level of neurotransmitters, but also modulate de novo gene transcription and synthesis of proteins involved in neural plasticity. In order to investigate the effects of antidepressant compounds on SVP-mRNA levels, the expressions of synaptophysin, synaptotagmin, VAMP, and synapsin-I were analysed by in situ hybridization in rats which had been treated with desipramine, fluoxetine, tranylcypromine, or saline. The results demonstrate that chronic treatment with fluoxetine and tranylcypromine leads to an increased expression of synaptophysin, but decreased expression of synaptotagmin and VAMP in the hippocampus and cerebral cortex. Additionally, synapsin I-mRNA levels in the hippocampus and cerebral cortex are significantly reduced in tranylcypromine-treated animals. This identifies SVP genes as target genes of antidepressant treatment.


Subject(s)
Antidepressive Agents/pharmacology , Membrane Proteins/physiology , Synaptic Vesicles/drug effects , Animals , Hippocampus/drug effects , Hippocampus/metabolism , Male , Rats , Rats, Sprague-Dawley , Synaptic Vesicles/physiology
10.
J Neural Transm (Vienna) ; 108(10): 1175-80, 2001.
Article in English | MEDLINE | ID: mdl-11725820

ABSTRACT

In order to identify gene variants related to the serotonergic neurotransmitter system that possibly represent a hereditary risk factor for sporadic Alzheimer's disease (AD), patients suffering from AD and non-demented psychiatric inpatients without symptoms of dementia were genotyped for polymorphisms of HTR6 (267C/T) and HTR2A (-1438G/A). Although there was a tendency toward an increased number of the genotype TT of the 5-HT6 receptor polymorphism in AD patients when compared to controls (2.8% vs. 1.3%), neither this nor the 5-HT2A promoter polymorphism showed significant differences in their genotypic or allelic distribution among patients and controls. These polymorphisms probably do not represent major genetic risk factors of AD. However, further studies including other genetic variants of the serotonergic neurotransmitter system are needed in order to elucidate their role in AD.


Subject(s)
Alzheimer Disease/genetics , Polymorphism, Genetic/genetics , Receptors, Serotonin/genetics , Alleles , Chi-Square Distribution , Genetic Variation/genetics , Genotype , Humans , Promoter Regions, Genetic/genetics , Receptor, Serotonin, 5-HT2A
11.
Biol Psychiatry ; 50(10): 809-12, 2001 Nov 15.
Article in English | MEDLINE | ID: mdl-11720700

ABSTRACT

BACKGROUND: In view of the effects of stress on synaptic plasticity, the regulation of synaptophysin and synaptotagmin expression by immobilization was analyzed by in situ hybridization. METHODS: Rats were exposed to immobilization stress, which induced typical behavioral alterations, such as reduced locomotor activity after stress exposure. Determination of mRNA levels of the integral synaptic vesicle proteins was performed immediately after acute or chronic immobilization. RESULTS: The results demonstrate that stress exposure leads to reduced expression of synaptophysin but increased expression of synaptotagmin in the hippocampus. CONCLUSIONS: This rapid and differential regulation of synaptic vesicle proteins could be responsible for some of the morphological, biochemical, and behavioral changes observed after stress exposure. These changes may be relevant to such clinical disorders as psychoses, depression, and posttraumatic stress disorder that are sensitive to stress and involve changes in neural and synaptic plasticity.


Subject(s)
Calcium-Binding Proteins , Hippocampus/pathology , Membrane Glycoproteins/genetics , Nerve Tissue Proteins/genetics , Stress, Psychological/complications , Synaptophysin/genetics , Animals , Gene Expression Regulation/physiology , Neuronal Plasticity/genetics , RNA, Messenger/genetics , Rats , Rats, Sprague-Dawley , Restraint, Physical , Stress, Psychological/pathology , Synaptotagmins
13.
Neurosci Lett ; 294(1): 63-5, 2000 Nov 10.
Article in English | MEDLINE | ID: mdl-11044587

ABSTRACT

The role of the deletion/insertion polymorphism within the promoter region of the serotonin transporter gene (5-HTT) is under discussion as a potential genetic risk factor for Alzheimers's disease (AD). Here we report significant differences in the allelic distribution of this polymorphism with a higher frequency of the short variant allele in AD patients when compared to controls. This difference was independent of the apolipoproteinE genotype. Thus, our study supports the notion that genetic alterations in the serontonergic neurotransmitter system may be involved in the etiopathogenesis of AD. However, given the reported negative findings, we are presently trying to identify diagnostic subgroups for which the 5-HTT promoter polymorphism represents a susceptibility locus.


Subject(s)
Alzheimer Disease/genetics , Carrier Proteins/genetics , Membrane Glycoproteins/genetics , Membrane Transport Proteins , Nerve Tissue Proteins , Polymorphism, Genetic , Promoter Regions, Genetic/genetics , Alleles , Alzheimer Disease/epidemiology , Apolipoprotein E4 , Apolipoproteins E/genetics , Female , Gene Frequency , Genetic Carrier Screening , Genetic Predisposition to Disease , Genetic Testing , Humans , Male , Prevalence , Risk Factors , Serotonin Plasma Membrane Transport Proteins , White People/genetics
14.
Nat Cell Biol ; 2(4): 205-11, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10783238

ABSTRACT

Mutations in the presenilin-1 (PS1) gene are associated with Alzheimer's disease and cause increased secretion of the neurotoxic amyloid-beta peptide (Abeta). Critical intramembraneous aspartates at residues 257 and 385 are required for the function of PS1 protein. Here we investigate the biological function of a naturally occurring PS1 splice variant (PS1 Deltaexon 8), which lacks the critical aspartate 257. Cell lines that stably express PS1 Deltaexon 8 or a PS1 protein in which aspartate residue 257 is mutated secrete significant levels of Abeta, whereas Abeta generation is severely reduced in cells transfected with PS1 containing a mutation of aspartate 385. In contrast, endoproteolytic processing of Notch is almost completely inhibited in cell lines expressing any of the PS1 variants that lack one of the critical aspartates. These data indicate that PS1 may differentially facilitate gamma-secretase-mediated generation of Abeta and endoproteolysis of Notch.


Subject(s)
Amyloid beta-Protein Precursor/metabolism , Membrane Proteins/genetics , Membrane Proteins/metabolism , Point Mutation , Alternative Splicing/physiology , Antibodies, Monoclonal , Aspartic Acid , Cell Line , Cell Membrane/chemistry , Cell Membrane/metabolism , Epitopes/genetics , Exons , Gene Expression/physiology , Humans , Kidney/cytology , Membrane Proteins/immunology , Presenilin-1 , Receptors, Notch , Signal Transduction/physiology
15.
Arch Biochem Biophys ; 373(2): 375-84, 2000 Jan 15.
Article in English | MEDLINE | ID: mdl-10620362

ABSTRACT

CYP3As represent a family of cytochromes P450 involved in the metabolism of both endogenous and exogenous natural and synthetic compounds. Well described in mammals, none have yet been cloned and characterized in avian species. In this paper, we report the cloning and analysis of an avian CYP3A (CYP3A37). Using an RNA differential display approach, an 80-bp phenobarbital-inducible cDNA fragment was amplified from chicken embryo liver. Based on its homology with mammalian CYP3As, this fragment was used to clone a full-length cDNA consisting of 1638 bp encoding a putative protein of 509 amino acids. The sequence shares between 57.4 and 62% identity at the amino acid level with CYP3As of other species. This cDNA was designated CYP3A37 according to the current cytochrome P450 nomenclature. When expressed in COS1 cells, the CYP3A37 cDNA produced a protein of congruent with55 kDa, which was recognized by polyclonal anti-rat CYP3A1 antiserum. In a bacterial expression system, the CYP3A37 cDNA produced a protein capable of steroid 6beta-hydroxylation. At a substrate concentration of 100 microM, progesterone, testosterone, and androstenedione were found to be 6beta-hydroxylated at a rate of 15.4, 11.7, 12.2 nmol/min/nmol P450, respectively. Used as control, the human CYP3A4 gave similar hydroxylation rates. Finally, in both chicken embryo liver and chicken hepatoma cells (LMH), CYP3A37 mRNA was increased after treatment with typical CYP3A inducers, such as metyrapone, phenobarbital, dexamethasone, and pregnenolone 16alpha-carbonitrile, but not rifampicin. CYP2H1, a well-characterized inducible chicken cytochrome P450, also was induced by the same compounds, suggesting similar regulation of CYP3 and CYP2 genes in this species.


Subject(s)
Aryl Hydrocarbon Hydroxylases , Cytochrome P-450 Enzyme System/genetics , Oxidoreductases, N-Demethylating/genetics , Amino Acid Sequence , Androstenedione/metabolism , Animals , Base Sequence , COS Cells , Cells, Cultured , Chick Embryo , Chickens , Cloning, Molecular , Cytochrome P-450 CYP3A , Cytochrome P-450 Enzyme System/biosynthesis , Cytochrome P-450 Enzyme System/chemistry , Enzyme Induction/drug effects , Molecular Sequence Data , Oxidoreductases, N-Demethylating/biosynthesis , Oxidoreductases, N-Demethylating/chemistry , Phenobarbital/pharmacology , Phylogeny , Progesterone/metabolism , RNA, Messenger/metabolism , Sequence Alignment , Substrate Specificity , Testosterone/metabolism
16.
Biochemistry ; 38(44): 14600-5, 1999 Nov 02.
Article in English | MEDLINE | ID: mdl-10545183

ABSTRACT

Alzheimer's disease (AD) is characterized by the invariant accumulation of senile plaques predominantly composed of the pathologically relevant 42-amino acid amyloid beta-peptide (Abeta42). The presenilin (PS) proteins play a key role in Abeta generation. FAD-associated mutations in PS1 and PS2 enhance the production of Abeta42, and PS1 is required for physiological Abeta production, since a gene knockout of PS1 and dominant negative mutations of PS1 abolish Abeta generation. PS proteins undergo endoproteolytic processing, and current evidence indicates that fragment formation may be required for the amyloidogenic function of PS. We have now determined the sequence requirements for endoproteolysis of PS1. Mutagenizing amino acids at the previously determined major cleavage site (amino acid 298) had no effect on PS1 endoproteolysis. In contrast, mutations or deletions at the additional cleavage site around amino acid 292 blocked endoproteolysis. The uncleavable PS1 derivatives accumulated as full-length proteins and replaced the endogenous PS1 proteins. In contrast to the previously described aspartate mutations within transmembrane domains 6 and 7, the uncleaved PS1 variants do not act as dominant negative inhibitors of Abeta production. Moreover, when a FAD-associated mutation (M146L) was combined with a mutation blocking endoproteolysis, Abeta42 production still reached pathological levels. These data therefore demonstrate that endoproteolysis of presenilins is not an absolute prerequisite for the amyloidogenic function of PS1. These data also show that accumulation of the PS1 holoprotein is not associated with the pathological activity of PS1 mutations as suggested previously.


Subject(s)
Alzheimer Disease/metabolism , Amyloid beta-Peptides/biosynthesis , Membrane Proteins/metabolism , Alzheimer Disease/genetics , Amino Acid Sequence , Binding Sites/genetics , Cell Line , DNA, Complementary/genetics , Endopeptidases/metabolism , Humans , Membrane Proteins/chemistry , Membrane Proteins/genetics , Mutation , Point Mutation , Presenilin-1 , Transfection
17.
J Biol Chem ; 274(40): 28669-73, 1999 Oct 01.
Article in English | MEDLINE | ID: mdl-10497236

ABSTRACT

Presenilin-1 (PS1) facilitates gamma-secretase cleavage of the beta-amyloid precursor protein and the intramembraneous cleavage of Notch1. Although Alzheimer's disease-associated mutations in the homologous presenilin (PS2) gene elevate amyloid beta-peptide (Abeta42) production like PS1 mutations, here we demonstrate that a gene ablation of PS2 (unlike that of PS1) in mice does not result in a severe phenotype resembling that of Notch-ablated animals. To investigate the amyloidogenic function of PS2 more directly, we mutagenized a conserved aspartate at position 366 to alanine, because the corresponding residue of PS1 is known to be required for its amyloidogenic function. Cells expressing the PS2 D366A mutation exhibit significant deficits in proteolytic processing of beta-amyloid precursor protein indicating a defect in gamma-secretase activity. The reduced gamma-secretase activity results in the almost complete inhibition of Abeta and p3 production in cells stably expressing PS2 D366A, whereas cells overexpressing the wild-type PS2 cDNA produce robust levels of Abeta and p3. Using highly sensitive in vivo assays, we demonstrate that the PS2 D366A mutation not only blocks gamma-secretase activity but also inactivates PS2 activity in Notch signaling by inhibiting the proteolytic release of the cytoplasmic Notch1 domain. These data suggest that PS2 is functionally involved in Abeta production and Notch signaling by facilitating similar proteolytic cleavages.


Subject(s)
Amyloid beta-Peptides/antagonists & inhibitors , Membrane Proteins/genetics , Membrane Proteins/metabolism , Mutation , Peptide Fragments/antagonists & inhibitors , Signal Transduction/genetics , Amyloid beta-Peptides/biosynthesis , Animals , Animals, Genetically Modified , Cell Line , Humans , Hydrolysis , Membrane Proteins/physiology , Mice , Mice, Knockout , Peptide Fragments/biosynthesis , Presenilin-2 , Receptors, Notch
18.
Rozhl Chir ; 75(1): 5-7, 1996 Jan.
Article in Czech | MEDLINE | ID: mdl-8768948

ABSTRACT

The authors submit an account of five patients with a perforated duodenal and prepyloric ulcer. All patients were treated by laparoscopy only. A laparoscopic suture of the perforated ulcer was made without omentoplasty with lavage and drainage. The patients recovered without complications. Early mobilisation and rapid convalescence are the greatest advantage of the minimal invasive approach in general. Laparoscopic treatment of a perforated ulcer is safe method when handled by an experienced laparoscopic surgeon.


Subject(s)
Duodenal Ulcer/surgery , Laparoscopy , Peptic Ulcer Perforation/surgery , Adult , Humans , Laparoscopy/methods , Sutures
19.
Rozhl Chir ; 74(6): 253-6, 1995 Sep.
Article in Czech | MEDLINE | ID: mdl-8658271

ABSTRACT

In the submitted review of the literature the authors evaluate contemporary therapeutic possibilities of mesenterial desmoids. A more detailed pattern of cytotoxic and non-cytotoxic chemotherapy, actinotherapy and hormonal therapy is presented. Surgical resection is limited by the size of the tumour and above all by early detection before the size of 15 cm is reached. In larger tumours conservative treatment by a combination of non-cytotoxic and hormonal treatment is better. Actinotherapy of the intraabdominal region is not suitable. The percentage of relapses is high, a standard therapeutic procedure has not been elaborated so far. Despite rather surprising remissions of desmoids in individual cases the general results of different groups are not encouraging. In a case-history the authors describe their experience with the treatment of a young female patient with a mesenterial desmoid which, however, was not successful.


Subject(s)
Fibromatosis, Aggressive/therapy , Mesentery , Peritoneal Neoplasms/therapy , Adult , Female , Fibromatosis, Aggressive/surgery , Humans , Peritoneal Neoplasms/surgery
20.
Rev. méd. Chile ; 122(6): 691-3, jun. 1994. ilus
Article in Spanish | LILACS | ID: lil-136208

ABSTRACT

We report two patients with hemobilia caused by hepatic artery aneurism that ruptured to the biliary tract. In the first patient, the diagnosis was made during an exploratory laparotomy. In the second patient, the aneurism was diagnosed with a selective hepatic artery arteriography and embolized during the procedure. The evolution of both patients was satisfactory


Subject(s)
Humans , Male , Female , Adolescent , Aged , Hemobilia/physiopathology , Angiography , Hemobilia/etiology , Gastrointestinal Hemorrhage/etiology , Aneurysm/complications , Hepatic Artery/physiopathology , Embolization, Therapeutic , Rupture, Spontaneous/complications
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