Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 52
Filtrar
2.
J Evol Biol ; 30(4): 696-710, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28106948

RESUMO

Tropical herbivorous insects are astonishingly diverse, and many are highly host-specific. Much evidence suggests that herbivorous insect diversity is a function of host plant diversity; yet, the diversity of some lineages exceeds the diversity of plants. Although most species of herbivorous fruit flies in the Neotropical genus Blepharoneura are strongly host-specific (they deposit their eggs in a single host plant species and flower sex), some species are collected from multiple hosts or flowers and these may represent examples of lineages that are diversifying via changes in host use. Here, we investigate patterns of diversification within six geographically widespread Blepharoneura species that have been collected and reared from at least two host plant species or host plant parts. We use microsatellites to (1) test for evidence of local genetic differentiation associated with different sympatric hosts (different plant species or flower sexes) and (2) examine geographic patterns of genetic differentiation across multiple South American collection sites. In four of the six fly species, we find evidence of local genetic differences between flies collected from different hosts. All six species show evidence of geographic structure, with consistent differences between flies collected in the Guiana Shield and flies collected in Amazonia. Continent-wide analyses reveal - in all but one instance - that genetically differentiated flies collected in sympatry from different host species or different sex flowers are not one another's closest relatives, indicating that genetic differences often arise in allopatry before, or at least coincident with, the evolution of novel host use.


Assuntos
Deriva Genética , Simpatria , Tephritidae/genética , Animais , Drosophila , Geografia
3.
Nurse Educ Pract ; 13(6): 561-6, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23602694

RESUMO

Within intellectual disability nursing students are prepared within a biopsychosocialeducational model and curriculum address these challenges. Using a simulated learning environment has great potential for promoting competence and in-depth knowledge of substantive topics relevant to practice. This article presents an assignment designed to more closely resemble real-world activities to allow students develop and exercise skills that translate to practice activities and incorporates a student's reflective comments on the process. The assignment was designed to foster intellectual disability student nurses ability to facilitate family/client education. The aim of the assignment was fulfilled through the students designing a clinical skill teaching session that could be used with families/clients. The sessions were recorded and the student reviewed their recording to reflect on their performance and to self assess. To facilitate student learning the modules academic lecturer also reviewed the recording and both lecturer and student meet to discuss the reflection and self assessment.


Assuntos
Competência Clínica , Bacharelado em Enfermagem/métodos , Aprendizagem , Estudantes de Enfermagem/psicologia , Gravação em Vídeo , Atitude do Pessoal de Saúde , Feminino , Humanos , Deficiência Intelectual/enfermagem , Masculino , Relações Enfermeiro-Paciente , Pesquisa em Educação em Enfermagem , Pesquisa em Avaliação de Enfermagem , Pesquisa Metodológica em Enfermagem , Educação de Pacientes como Assunto , Relações Profissional-Família , Autoavaliação (Psicologia)
4.
Nurse Educ Pract ; 12(4): 232-7, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22475508

RESUMO

Assessment has long been recognised as the single most influential factor in shaping what and how students in higher education choose to learn and the quality of learning outcomes depends on the quality of assessment. Within intellectual disability nursing the student are prepared within a biopsychosocial educational model and curriculum address these challenges. Structured student debates have great potential for promoting competence and in-depth knowledge of substantive topics relevant to practice. Like other interactive assignments designed to more closely resemble real-world activities, issue-oriented debates actively engage students in course content. Allowing students to develop and exercise skills that translate to practice activities. Most importantly debates help to stimulate critical thinking by shaking students free from established opinions and helping them to appreciate the complexities involved in practice. This article identifies the use of a debate as an assessment method within an intellectual disability nursing programme and a student's reflective comment on the process, and their experience of a debate as their assessment method.


Assuntos
Competência Clínica , Educação em Enfermagem/organização & administração , Avaliação Educacional/métodos , Estudantes de Enfermagem/psicologia , Aprendizagem Verbal , Atitude do Pessoal de Saúde , Humanos , Pesquisa em Educação em Enfermagem , Pesquisa em Avaliação de Enfermagem , Pesquisa Metodológica em Enfermagem
5.
J Oral Rehabil ; 38(7): 501-8, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21133984

RESUMO

This study was undertaken in a young Irish population to determine the dimensions and ratios of the six maxillary anterior teeth. One hundred and nine Irish subjects (age 18-25 inclusive) had irreversible hydrocolloid impressions made of their maxillary dentition poured in type V stone. Clinical crown dimensions were measured with a digital calliper. The stone casts were digitally photographed in a standardised manner enabling calculation of various ratios between the maxillary anterior teeth. Sexual dimorphism existed for various tooth dimensions; most notably canine teeth were in the region of 0·8 mm longer and 0·6 mm wider in males. Central and lateral incisors were found to be 0·5 mm wider in males. It is, therefore, recommended that dimensional tooth guidelines should be given for each of the sexes and not on a population basis. With regard to tooth proportion ratios, no significant differences were found between genders or the left and right sides for any of the measurements or ratios measured. The digitally recorded tooth proportions were similar for both sexes, and the Golden Proportion guidelines could only be applied to the lateral incisor/central incisor widths (0·618). Identified width proportions for the canine/central incisor were 0·58 and for canine/lateral incisor 0·89.


Assuntos
Dente Canino/anatomia & histologia , Maxila/anatomia & histologia , Adolescente , Adulto , Análise de Variância , Feminino , Humanos , Irlanda/etnologia , Masculino , Odontometria , Linhagem , Fotografia Dentária , Valores de Referência , Reprodutibilidade dos Testes , População Branca/etnologia , Adulto Jovem
6.
Mutat Res ; 629(1): 24-31, 2007 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-17276720

RESUMO

Although there has been a rapid rise in the application of fluorescent in situ hybridization (FISH) analysis of bone marrow tissue for the staging and prognosis determination of hematopoietic malignacies such as the chronic and acute leukemias, it's application as a surveillance tool for leukemogen exposed high risk occupational cohorts is understandably limited by the invasiveness of sample collection. While some small occupational studies have been performed using FISH in peripheral blood with promising results, some of the basic assumptions made in utilizing the FISH technique have not been fully explored. These include selection of the correct hematopoietic cell to assay (myeloid or lymphoid); selection of appropriate chromosomal markers and the sensitivity of peripheral blood FISH in detecting unbalanced genomic abnormalities. In this study, we performed a pilot 'validation' exercise utilizing the FISH technique and standard metaphase cytogenetics, comparing results in tandem pairs of peripheral blood with bone marrow cells, where clonal abnormalities arise. Samples were taken from patients with known chromosomal lesions associated with active leukemia. We carefully chose markers most frequently associated with leukemogen-inducing DNA damage and probes that have been utilized successfully in clinical practice. Ten de novo or therapy-related acute myeloid leukemia (t-AML) patients underwent bone marrow cell karyotyping and fluorescent in situ hybridization (FISH) analysis. Parallel peripheral blood samples were concommitently drawn and evaluated with FISH using the same probes. In six of eight paired samples treated with a 3-day phytohemagglutinin (PHA) stimulation, typically used to assay lymphocytes and their progenitors, we detected abnormal clones. In one of the two remaining cases, we identified an abnormal clone in both bone marrow and PHA-stimulated peripheral blood, although at a level in the peripheral blood sample that would typically be reported as "non-diagnostic" for clinical purposes. These results suggest that use of FISH in PHA stimulated peripheral blood samples with probes commonly employed in t-AML evaluations (chromosomes 5q, 7q, 8, 11q) to detect cytogenetic abnormalities in peripheral blood represents a potentially promising though as yet, under-utilized approach for the occupational surveillance of workers exposed to leukemogens, especially if it could be linked to automated high-throughput assays for increased sensitivity.


Assuntos
Células da Medula Óssea/patologia , Hibridização in Situ Fluorescente/métodos , Leucemia Mieloide Aguda/patologia , Leucócitos Mononucleares/metabolismo , Exposição Ocupacional/efeitos adversos , Vigilância da População , Cromossomos Humanos Par 11 , Cromossomos Humanos Par 5 , Cromossomos Humanos Par 7 , Cromossomos Humanos Par 8 , Estudos de Coortes , Análise Citogenética/métodos , Humanos , Cariotipagem , Projetos Piloto , Reprodutibilidade dos Testes
7.
An Sist Sanit Navar ; 28(1): 83-92, 2005.
Artigo em Espanhol | MEDLINE | ID: mdl-15827581

RESUMO

INTRODUCTION: Disability produced by locomotor pathology causes a loss in working hours and indirect costs that are increasing at a growing rate. The aims of this study are to estimate the costs in total working hours lost caused by this pathology in two health areas of Navarra with 441,600 inhabitants, to obtain standards for the duration and incidence of sick leave and to study the relation between the average duration of sick leave and variables such as the geographical accessibility of the rehabilitation services, residence in a rural or urban milieu, and between the different health areas. METHODS: We study all the processes of temporary disability due to pathology of the locomotor system in Health Areas I and III of Navarra in 1997 and 1998, taking different variables into account. We make a descriptive study of the pathologies, counting the working days lost. We calculate the annual incidence of sick leave because of pathologies. We compare average duration with other variables. RESULTS: These represent 221,054 lost working days per year. Low back pain and sprained ankles are the most frequent processes. We find an increase in the incidence of temporary disability due to low back pain and lumbar/sciatica in the basic rural areas of the middle region. There are no statistically significant differences with a p<0.05 in the duration of temporary disability according to Health Area, rural or urban milieu or geographical accessibility to the Rehabilitation Services. A statistically significant fall can be observed in the first year of operation of a temporary disability management program.


Assuntos
Doenças Musculoesqueléticas/epidemiologia , Doenças Profissionais/epidemiologia , Absenteísmo , Avaliação da Deficiência , Humanos , Incidência , Serviços de Saúde do Trabalhador/estatística & dados numéricos , Licença Médica/estatística & dados numéricos , Espanha/epidemiologia
8.
An. sist. sanit. Navar ; 28(1): 83-92, ene.-mar. 2005. ilus, tab
Artigo em Es | IBECS | ID: ibc-038431

RESUMO

Introducción. La discapacidad producida por la patologíadel aparato locomotor ocasiona una pérdida de horas de trabajoy unos costes indirectos que están aumentando a un ritmocreciente. Los objetivos de este estudio son estimar los costesen horas de trabajo totales perdidas ocasionadas por la patologíadel aparato locomotor en 2 áreas sanitarias de Navarra con 441.600 habitantes, obtener estándares de duración e incidenciade bajas y estudiar la relación entre duración media de las bajasy variables como la accesibilidad geográfica a los servicios derehabilitación, vivir en entorno rural o urbano y entre diferentesáreas sanitarias.Material y métodos. Se han estudiado todos los procesosde incapacidad temporal por patología del aparato locomotoren las Áreas Sanitarias I y III de Navarra en 1997 y 1998, recogiendodiferentes variables. Se ha realizado un estudio descriptivode las patologías, contabilizando las jornadas laborales perdidas.Calculamos la incidencia anual de bajas por patologías.Comparamos duración media con otras variables.Resultados. La discapacidad producida por la patología delaparato locomotor supone pérdidas de 221.054 jornadas de trabajo/año. La lumbalgia, el esguince de tobillo son los procesosmás frecuentes. Encontramos un aumento en la incidencia deincapacidad temporal por lumbalgia y lumbociatalgia en laszonas básicas rurales de la zona media. No existen diferenciasestadísticamente significativas con una p<0,05 en la duración dela incapacidad temporal según área sanitaria, entorno rural ourbano ni accesibilidad geográfica a los servicios de rehabilitación.Se observa un descenso significativo estadísticamente elprimer año de funcionamiento de un programa de gestión deincapacidad temporal


pahtology causes a loss in working hours and indirect coststhat are increasing at a growing rate. The aims of this studyare to estimate the costs in total working hours lost caused bythis pathology in two health areas of Navarra with 441,600inhabitants, to obtain standards for the duration andincidence of sick leave and to study the relation between theaverage duration of sick leave and variables such as thegeographical accessibility of the rehabilitation services,residence in a rural or urban milieu, and between the differenthealth areas.Methods. We study all the processes of temporarydisability due to pathology of the locomotor system in HealthAreas I and III of Navarra in 1997 and 1998, taking differentvariables into account. We make a descriptive study of thepathologies, counting the working days lost. We calculate theannual incidence of sick leave because of pathologies. Wecompare average duration with other variables.Results. These represent 221,054 lost working days peryear. Low back pain and sprained ankles are the most frequentprocesses. We find an increase in the incidence of temporarydisability due to low back pain and lumbar/sciatica in the basicrural areas of the middle region. There are no statisticallysignificant differences with a p<0.05 in the duration oftemporary disability according to Health Area, rural or urbanmilieu or geographical accessibility to the RehabilitationServices. A statistically significant fall can be observed in thefirst year of operation of a temporary disability managementprogram


Assuntos
Humanos , Doenças Musculoesqueléticas/epidemiologia , Doenças Profissionais/epidemiologia , Avaliação da Deficiência , Incidência , Licença Médica/estatística & dados numéricos , Espanha/epidemiologia , Absenteísmo , Serviços de Saúde do Trabalhador/estatística & dados numéricos
9.
Heart ; 89(7): 752-6, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12807849

RESUMO

OBJECTIVES: To determine whether pregnancy is well tolerated in hypertrophic cardiomyopathy. SETTING: Referral clinic. DESIGN: The study cohort comprised 127 consecutively referred women with hypertrophic cardiomyopathy. Forty (31.5%) underwent clinical evaluation before pregnancy. The remaining 87 (68.5%) were referred after their first pregnancy. All underwent history, examination, electrocardiography, and echocardiography. Pregnancy related symptoms and complications were determined by questionnaire and review of medical and obstetric records where available. RESULTS: There were 271 pregnancies in total. Thirty six (28.3%) women reported cardiac symptoms in pregnancy. Over 90% of these women had been symptomatic before pregnancy. Symptoms deteriorated during pregnancy in fewer than 10%. Of the 36 women with symptoms during pregnancy, 30 had further pregnancies. Symptoms reoccurred in 18 (60%); symptomatic deterioration was not reported. Heart failure occurred postnatally in two women (1.6%). No complications were reported in 19 (15%) women who underwent general anaesthesia and in 22 (17.4%) women who received epidural anaesthesia, three of whom had a significant left ventricular outflow tract gradient at diagnosis after pregnancy. Three unexplained intrauterine deaths occurred in women taking cardiac medication throughout pregnancy. No echocardiographic or clinical feature was a useful indicator of pregnancy related complications. CONCLUSIONS: Most women with hypertrophic cardiomyopathy tolerate pregnancy well. However, rare complications can occur and therefore planned delivery and fetal monitoring are still required for some patients.


Assuntos
Cardiomiopatia Hipertrófica/complicações , Complicações Cardiovasculares na Gravidez , Adulto , Idoso , Anestesia Geral/estatística & dados numéricos , Anestesia Obstétrica/estatística & dados numéricos , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Cardiomiopatia Hipertrófica/tratamento farmacológico , Estudos de Coortes , Dispneia/etiologia , Ecocardiografia , Feminino , Humanos , Pessoa de Meia-Idade , Complicações do Trabalho de Parto/etiologia , Gravidez , Resultado da Gravidez , Transtornos Puerperais/etiologia , Ultrassonografia Pré-Natal
10.
Shock ; 16(3): 189-95, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11531020

RESUMO

The objective of the present study was to determine whether hypoxia/reoxygenation in the absence or presence of intestinal bacteria would affect the integrity of the gut mucosal epithelium (as evidenced by histologic changes) and increase the local production of cytokines (interleukin 6 [IL-6] and tumor necrosis factor [TNF]). Rat ileal mucosal membranes were harvested and their electrophysiologic properties and barrier function were measured ex vivo in the Ussing chamber system. Membranes were exposed to normoxia, normoxia + Escherichia coli, hypoxia for 40 min followed by normoxia, or hypoxia for 40 min + E. coli followed by normoxia for 3 h. IL-6 and TNF levels were measured using cytokine-dependent cellular assays. Morphological changes and the degree of DNA fragmentation were used as quantitative markers of gut mucosal injury. Mucosal integrity was maintained in the normoxia group. The addition of bacteria increased the IL-6 response and reduced mucosal integrity. During the hypoxic period, a transient decline in resistance (R) occurred and cytokine production was reduced. In the hypoxic ileal membranes not exposed to E coli, reoxygenation reversed the change in R and increased IL-6 production. The combination of hypoxia/reoxygenation plus E. coli bacterial challenge resulted in the greatest extent of gut mucosal injury and increase in TNF production. The results of this study support the hypothesis that the combination of increased intestinal bacterial levels superimposed on an ischemia/reperfusion injury increases the magnitude of gut mucosal injury and the production and subsequent release of proinflammatory cytokines.


Assuntos
Citocinas/metabolismo , Fragmentação do DNA , Escherichia coli/fisiologia , Hipóxia/fisiopatologia , Mucosa Intestinal/fisiopatologia , Traumatismo por Reperfusão/fisiopatologia , Animais , Eletrofisiologia , Hipóxia/genética , Hipóxia/metabolismo , Técnicas In Vitro , Mucosa Intestinal/patologia , Masculino , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/metabolismo
11.
J Clin Pharmacol ; 40(7): 708-12, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10883411

RESUMO

Medieval and Renaissance teaching techniques using linkage between course content and tangentially related visual symbols were applied to the teaching of the pharmacological principles of addiction. Forty medical students randomly divided into two blinded groups viewed a lecture. One lecture was supplemented by symbolic slides, and the second was not. Students who viewed symbolic slides had significantly higher scores in a written 15-question multiple-choice test 30 days after the lecture. These results were consistent with learning and semiotic models. These models hypothesize a linkage between conceptual content and perception of visual symbols that thereby increases conceptual retention. Recent neurochemical research supports the existence of a linkage between two chemically distinct memory systems. Simultaneous stimulation of both chemical systems by teaching formats similar to those employed in the study can augment neurochemical signaling in the neocortex.


Assuntos
Recursos Audiovisuais , Educação Médica/métodos , Memória , Farmacologia Clínica/educação , Adulto , Comunicação , Feminino , Humanos , Aprendizagem , Masculino , Estudantes de Medicina , Transtornos Relacionados ao Uso de Substâncias
12.
Psychiatry Res ; 93(1): 83-7, 2000 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-10699232

RESUMO

The authors compared the antimanic effects of a verapamil-magnesium oxide (V-M) combination with a verapamil-placebo combination (V-P) in patients pretreated with verapamil. BPRS scores and serum magnesium levels were compared. The V-M combination was found to be significantly more effective than V-P in reducing manic symptoms (P=0.015). Serum magnesium levels were significantly higher in the V-M group (P<0.04). These data suggest that magnesium may increase antimanic efficacy of verapamil by mechanisms which may operate at the intracellular level. The magnesium-verapamil combination may have clinical application as an adjunct to verapamil in the maintenance therapy of mania.


Assuntos
Antimaníacos/uso terapêutico , Transtorno Bipolar/tratamento farmacológico , Magnésio/uso terapêutico , Verapamil/uso terapêutico , Adulto , Antimaníacos/administração & dosagem , Transtorno Bipolar/sangue , Dieta , Quimioterapia Combinada , Humanos , Magnésio/administração & dosagem , Magnésio/sangue , Masculino , Escalas de Graduação Psiquiátrica , Resultado do Tratamento , Verapamil/administração & dosagem
13.
Am J Ther ; 7(6): 389-91, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11304647

RESUMO

In an open, double-blind study of phencyclidine intoxication, 21 white male subjects were later found to have instead ingested ketamine. These subjects were divided into two cohorts, one treated with 5 mg intramuscular haloperidol and the second with an active placebo. Assessment with the Brief Psychiatric Rating Scale revealed significant reduction in symptoms with haloperidol.


Assuntos
Anestésicos Dissociativos/intoxicação , Antipsicóticos/uso terapêutico , Haloperidol/uso terapêutico , Ketamina/intoxicação , Psicoses Induzidas por Substâncias/tratamento farmacológico , Adulto , Método Duplo-Cego , Humanos , Masculino
14.
Ir Med J ; 92(6): 396-8, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10598420

RESUMO

In February 1996, four serologically confirmed cases of hepatitis A virus (HAV) occurred in one household. Investigation showed that the source was a family member with sub-clinical HAV who attended a Unit for Learning Disabilities. Reports of two further cases in the institution followed and control measures were instigated. Contacts were unwilling to accept human normal immunoglobulin (HNIG). Following salivary antibody and serological testing, hepatitis A vaccine was offered to the non-immune. An investigation found that sub-clinical infection was significantly associated with being less than 5 years old (RR = 6.07, p < 0.005) and being in one particular classroom (RR = 6.21, p < 0.0005). None of the staff in the institution became infected. In all, 31 cases of hepatitis A (18 clinical and 13 subclinical cases) occurred. This paper (a) describes an outbreak of hepatitis A (b) refers to the use of a salivary antibody test (assay performance to be published elsewhere) (c) identifies factors associated with the acquisition of HAV and (d) endeavours to assess the effectiveness of the vaccine to contain the outbreak.


Assuntos
Surtos de Doenças , Hepatite A/epidemiologia , Vacinas contra Hepatite Viral/administração & dosagem , Academias e Institutos , Adulto , Criança , Vacinas contra Hepatite A , Humanos , Irlanda/epidemiologia , Deficiências da Aprendizagem , Vacinação
15.
Infect Immun ; 67(9): 4787-93, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10456932

RESUMO

Multicellular organisms utilize a battery of extracellular and cellular mechanisms to defend against microbial infiltration. Among the armamentarium used by the small intestine to defend against microbial invasion are antimicrobial peptides called defensins. We previously have shown that gut barrier function is impaired following hemorrhagic shock, resulting in translocation of bacteria or endotoxin. Using a rat model, we examined the effect of hemorrhagic shock on alpha-defensin expression. We utilized the anchored reverse transcriptase PCR strategy to isolate a rat enteric defensin cDNA. The cDNA is 406 bases in length and encodes a putative prepro-enteric defensin that we have named rat defensin 5 (RD-5). RD-5 expression is restricted to the small intestine and is specifically localized by in situ hybridization to the Paneth cells. A 10-fold increase in its steady state levels was observed in the distal intestine immediately after the termination of shock. This is the first study to show that enteric defensins are inducible following injury. We suggest that enteric defensins may contribute to the complex and integrated barrier function of the intestinal mucosal surface.


Assuntos
Proteínas/genética , Choque Hemorrágico/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA Complementar , Defensinas , Modelos Animais de Doenças , Expressão Gênica , Masculino , Camundongos , Dados de Sequência Molecular , Biossíntese de Proteínas , RNA Mensageiro , Ratos , Ratos Sprague-Dawley , Choque Hemorrágico/imunologia , Choque Hemorrágico/patologia , Distribuição Tecidual
16.
Mol Carcinog ; 25(3): 179-86, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10411144

RESUMO

Treatment of rats with N-methyl-N-nitrosourea (MNU) and testosterone results in a high incidence of metastasizing dorsolateral prostate tumors. In previous studies, a high frequency (> or = 70%) of a G35 --> A transition mutation at the second position of codon 12 of the Ki-ras oncogene was found in these tumors. This was confirmed in the study reported here, and the frequency of this mutation appeared similar in tumors induced in four different rat strains, regardless of differences in sensitivity among these strains to the induction of prostate cancers by MNU and testosterone: Wistar Furth (62% incidence of grossly visible prostate tumors) > Lobund Wistar (55%) > Fisher 344 (40%) > Copenhagen (37%). A method was developed to isolate and separately culture epithelial and stromal cells from these rat prostate carcinomas. Of 20 primary cell cultures established from histologically confirmed rat prostate carcinomas, 19 (95%) displayed one or more of the following characteristics: the Ki-ras mutation (17 of 20; 85%), anchorage-independent growth in soft agar at early passage (12 of 20; 60%), or tumorigenicity at later passage (eight of eight; 100%). One epithelial cell culture and all five stromal cell cultures established from prostate tumors had none of these characteristics. Epithelial cultures that had the Ki-ras mutation and grew in soft agar constitute the predominant genotype/phenotype (55%), cultures with the mutation that did not grow in soft agar were less frequent (30%), 10% of the cultures had neither characteristic, and only one grew in soft agar but did not have the mutation. These findings suggest that there are at least two and perhaps more different molecular pathways of prostate carcinogenesis in rats treated with MNU plus testosterone. Furthermore, these data suggest that these pathways and the mechanisms determining strain differences in sensitivity to prostate cancer induction are unrelated.


Assuntos
Transformação Celular Neoplásica/efeitos dos fármacos , Metilnitrosoureia/farmacologia , Próstata/efeitos dos fármacos , Testosterona/farmacologia , Animais , Sequência de Bases , Adesão Celular , Células Cultivadas , Primers do DNA , Genes ras , Genótipo , Masculino , Mutação , Fenótipo , Próstata/citologia , Neoplasias da Próstata/induzido quimicamente , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Ratos , Especificidade da Espécie
17.
In Vivo ; 13(1): 61-5, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10218135

RESUMO

Prostate cancer is one of the most common malignancies in males, and tumor progression critically determines its clinical significance. Prostatic stromal cells may be critically involved in growth and progression of prostate cancer. There is substantial evidence that the stromal component of the embryological tissue of origin, the urogenital sinus, is essential in directing outgrowth and prostatic differentiation of the epithelial anlage of the prostate. The presence of a stromal androgen receptor is required for this effect, and humoral factors, such as keratinocyte growth factor, have been shown to be able to mediate it in a paracrine fashion. The adult prostate is also under control of multiple steroid hormone and paracrine peptide factors, and there is evidence that the prostatic stroma plays a major role in mediation of androgen effects on prostatic epithelium. Normal seminal vesicle mesenchyme can cause differentiation of the Dunning R3327H prostate carcinoma. Normal rat prostatic fibroblasts influence the in vivo and soft agar growth of epithelial cells derived from chemically/hormonally induced rat prostate carcinomas, as do fibroblasts that are isolated from these tumors. Both growth-enhancing and growth-inhibiting effects were observed, apparently depending on the stage of progression of both cell types as well as on whether fibroblasts were derived from the same or a different tumor than the epithelial cells. These findings indicate that stromal cells critically influence epithelial prostate cancer growth, and they suggest that these effects can significantly vary in different tumors as well as in different stages of tumor progression.


Assuntos
Neoplasias da Próstata/fisiopatologia , Células Estromais/fisiologia , Androgênios , Animais , Progressão da Doença , Humanos , Masculino , Ratos
18.
Dig Dis Sci ; 44(3): 465-78, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10080136

RESUMO

Increased mucosal apoptosis is seen in H. pylori-infected gastric tissue; however, the precise mechanism by which this organism triggers programmed cell death is poorly understood and is investigated in this study. One pathway for induction of apoptosis is the Fas Ag pathway. Normal gastric and small bowel tissue express low levels of Fas antigen and nondetectable levels of Fas ligand. Consequent to H. pylori infection, there is elevated expression of Fas antigen in mucosal cells concurrent with Fas ligand expressing lymphocytes. This prompted us to investigate the potential role of Fas in mediating H. pylori-related apoptosis. It has been shown that inflammatory cytokines are abundant in H. pylori-infected tissue and that cytokines regulate the expression of Fas Ag in various tissue types. Using cell culture, we examine the role of specific inflammatory cytokines in activating this pathway. This communication presents the first evidence to implicate the Fas pathway in mediating apoptosis in H. pylori-associated gastric and duodenal ulcer disease.


Assuntos
Apoptose , Úlcera Duodenal/patologia , Infecções por Helicobacter/patologia , Helicobacter pylori , Úlcera Gástrica/patologia , Receptor fas/fisiologia , Linhagem Celular , Células Cultivadas , Úlcera Duodenal/microbiologia , Mucosa Gástrica/patologia , Humanos , Mucosa Intestinal/patologia , Úlcera Gástrica/microbiologia
19.
J Learn Disabil ; 32(2): 150-8, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-15499715

RESUMO

A few studies have shown more central auditory processing deficits in children with attention-deficit/hyperactivity disorder (ADHD) than in nondisabled children. Because these studies failed to screen participants with ADHD for learning disabilities (LD), it is not clear whether these deficits are correlates of ADHD or LD or both. In the present study, the central auditory processing ability of children with ADHD, ADHD with LD, and no disabilities was examined. Results indicated lower central auditory processing ability, and significant correlations between reading and ADHD symptoms and reading and central auditory processing ability in the ADHD with LD group compared with the other two groups. These findings suggest that central auditory processing deficits are more likely to be associated with LD than ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtornos da Percepção Auditiva/diagnóstico , Deficiências da Aprendizagem/diagnóstico , Criança , Comorbidade , Educação Inclusiva , Feminino , Humanos , Masculino , Testes Neuropsicológicos/estatística & dados numéricos , Psicometria/estatística & dados numéricos , Valores de Referência , Estatística como Assunto , Baixo Rendimento Escolar
20.
J Bacteriol ; 180(24): 6773-5, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9852030

RESUMO

A mutant of Mycobacterium smegmatis unable to use the dipeptide carnosine (beta-alanyl-L-histidine) as a sole carbon or nitrogen source was isolated. Carnosinase activity and the ability to grow on beta-Ala and/or L-His were similar in the mutant and the wild type. However, the mutant showed significant impairment in the uptake of carnosine. This study is the first description of a peptide utilization mutant of a mycobacterium.


Assuntos
Dipeptídeos/metabolismo , Mutação , Mycobacterium smegmatis/metabolismo , Transporte Biológico , Carnosina/metabolismo , Mycobacterium smegmatis/genética , Mycobacterium smegmatis/crescimento & desenvolvimento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...