Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 49
Filtrar
1.
Arch. alerg. inmunol. clin ; 47(1): 6-13, 2016. ilus
Artigo em Espanhol | LILACS | ID: biblio-914879

RESUMO

Fundamento. La polución biológica natural puede causar o agravar procesos alérgicos. En la ciudad de Bahía Blanca se realizan monitoreos continuos de granos de polen desde 1994. Sin embargo, al no contar con información sistematizada sobre las enfermedades alérgicas, se desconoce si existe relación entre los efectos de la polución y la prevalencia de éstas en la población local. Objetivo. Conocer la prevalencia de enfermedades alérgicas y síntomas asociados en dos grupos poblacionales de la ciudad de Bahía Blanca. Lugar. Municipalidad de Bahía Blanca y Universidad Nacional del Sur. Diseño. Estudio de corte transversal con modalidad de encuesta, tomando una muestra representativa de cada población. Población. Empleados municipales y población universitaria. Método. Fue elaborado un cuestionario ad hoc, incluyendo preguntas del cuestionario ISAAC. Para todos los análisis se utilizó el software R, con el objetivo de realizar una regresión logística para el análisis de los resultados obtenidos. Para analizar el riesgo de padecimiento se utilizaron odds ratio y su correspondiente valor p (IC95% y un error del 2%). Resultados. El 22,72% de los encuestados refirió padecer alguna enfermedad alérgica diagnosticada. El 53,13% de quienes manifestaron síntomas no declararon padecer enfermedad. Se observó asociación estadísticamente significativa entre conjuntivitis y poseer mascotas (OR=2,5; p=0,02); y entre SIR y presencia de humedad en las paredes (OR=1,8; p<0,05). La regresión logística mostró asociación entre padecer enfermedad alérgica y antecedentes familiares de las mismas (p=3,97e­16) y entre padecer asma o SIA y el hábito de fumar (p=0,0002). Conclusiones. Las prevalencias encontradas para cada enfermedad alérgica indagada y sus síntomas coinciden con las halladas en estudios previos en la ciudad. Existe un alto subdiagnóstico manifestado en la referencia de síntomas asociados.(AU)


Background. The natural biological pollution can cause or exacerbate allergies. A continuous monitoring of pollen grains is performed in Bahía Blanca city since 1994. However, due to the lack of systematic information of these allergic diseases it is unknown whether there is or not a relationship between pollution effects and disease prevalence in the local population. Objective. Determine the prevalence of allergic diseases and its associated symptoms in two groups of people in Bahía Blanca's city. Location. Bahía Blanca's city hall and National University of the South. Design. Cross-sectional study, implementing a survey and taking a representative sample of each group. Population. Municipal employees and university population. Method. It was elaborated an ad hoc survey, including questions from the ISAAC questionnaire. The R software was used for all the analysis, in order to perform a logistic regression analysis. The odds ratio and its corresponding p value (CI95% and 2% error) were used in order to analyze the diseases index. Results. The 22.72% of the interviewed mentioned to suffer some diagnosed allergic disease. The 53.13% of those who showed symptoms denied suffering from any disease. Statistically significant association was observed between conjunctivitis and own pets (OR=2.5; p=0.02); and between SIR and the presence of damp walls (OR=1.8; p<0.05). The logistic regression analysis showed an association between allergic disease and family history of the same disease (p=3.97 e­16) and between asthma or SIA and smoking habits (p=0.0002). Conclusions. The prevalence found for each allergic disease and its investigated symptoms agreed with those previously found in other local studies. There was a high sub-diagnosis manifested in reference to associated symptoms.(AU)


Assuntos
Humanos , Asma , Rinite Alérgica , Hipersensibilidade , Prevalência
2.
Allergol. immunopatol ; 41(5): 310-314, sept.-oct. 2013. tab
Artigo em Inglês | IBECS | ID: ibc-116401

RESUMO

Background: Food allergy has been gaining increasing attention, mostly as causing gastrointestinal and cutaneous reactions. Its role in asthma seems to be under-recognised. Objectives: This study's aim is to explore the frequency of involvement of a common food, namely cow's milk, in childhood asthma.Methods32 children (5 months to 11 years; median 24 months; mean 34 months) with asthma and a suspected history of cow's milk allergy were studied. They underwent skin prick testing (SPT) and specific IgE (sIgE) testing to whole cow's milk (WCM), casein, α-lactalbumin, and β-lactoglobulin, followed by single-blind oral milk challenge. Results: Reactions to milk challenge occurred in 12 (37.5%) including wheezing in 5 (41.7%, or 15.6% of the whole group). Children who developed wheezing at the time of challenge were younger than those who had negative challenge (23.0 months vs. 34.8 months). Challenge was positive in 33.3% of subjects who had a positive SPT, and SPT was positive in 50% of challenge-positive subjects. Regarding sIgE, challenge was positive in 26.7% of sIgE-positive subjects, and sIgE was positive in 33.3% of challenge positive subjects. Skin or serum testing with individual protein fractions did not seem to add significant advantage over testing with WCM alone. Conclusion: This study shows that cow's milk can cause wheezing in children with asthma. Although SPT seemed to be more reliable than sIgE testing, both had suboptimal reliability. It is worth considering possible milk allergy in children with asthma, particularly when poorly controlled in spite of proper routine management (AU)


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Sons Respiratórios/etiologia , Leite/efeitos adversos , Asma/complicações , Substitutos do Leite Humano , Fatores de Risco
3.
Allergol Immunopathol (Madr) ; 41(5): 310-4, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23141754

RESUMO

BACKGROUND: Food allergy has been gaining increasing attention, mostly as causing gastrointestinal and cutaneous reactions. Its role in asthma seems to be under-recognised. OBJECTIVES: This study's aim is to explore the frequency of involvement of a common food, namely cow's milk, in childhood asthma. METHODS: 32 children (5 months to 11 years; median 24 months; mean 34 months) with asthma and a suspected history of cow's milk allergy were studied. They underwent skin prick testing (SPT) and specific IgE (sIgE) testing to whole cow's milk (WCM), casein, α-lactalbumin, and ß-lactoglobulin, followed by single-blind oral milk challenge. RESULTS: Reactions to milk challenge occurred in 12 (37.5%) including wheezing in 5 (41.7%, or 15.6% of the whole group). Children who developed wheezing at the time of challenge were younger than those who had negative challenge (23.0 months vs. 34.8 months). Challenge was positive in 33.3% of subjects who had a positive SPT, and SPT was positive in 50% of challenge-positive subjects. Regarding sIgE, challenge was positive in 26.7% of sIgE-positive subjects, and sIgE was positive in 33.3% of challenge positive subjects. Skin or serum testing with individual protein fractions did not seem to add significant advantage over testing with WCM alone. CONCLUSION: This study shows that cow's milk can cause wheezing in children with asthma. Although SPT seemed to be more reliable than sIgE testing, both had suboptimal reliability. It is worth considering possible milk allergy in children with asthma, particularly when poorly controlled in spite of proper routine management.


Assuntos
Asma/imunologia , Hipersensibilidade a Leite/imunologia , Alérgenos/imunologia , Animais , Asma/complicações , Asma/diagnóstico , Bovinos , Criança , Pré-Escolar , Feminino , Humanos , Imunoglobulina E/sangue , Lactente , Recém-Nascido , Masculino , Hipersensibilidade a Leite/complicações , Hipersensibilidade a Leite/diagnóstico , Proteínas do Leite/imunologia , Prevalência , Sons Respiratórios/etiologia , Testes Cutâneos
4.
Mil Med ; 166(11): 972-81, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11725326

RESUMO

BACKGROUND: Unexplained symptoms have frequently been observed in deployed Persian Gulf War veterans (GWVs). Using factor analysis, the Centers for Disease Control and Prevention (CDC) has established criteria for Gulf War illness (GWI). We report here on the prevalence of GWI, identify comorbidities, and compare these with those of veterans without GWI. METHODS: GWVs who consented to complete questionnaires and laboratory measures were given complete physical and mental health examinations. Outcome measures included CDC criteria for GWI, the Medical Outcomes Study Short Form 36 (SF-36), clinical and laboratory evaluations, and structured psychiatric interviews. RESULTS: One hundred twenty GWVs were enrolled, and 89 received complete physical and mental health examinations; 83% met CDC criteria for GWI. Veterans with GWI (1) were older, (2) reported more combat exposure, (3) scored higher on measures of depression, post-traumatic stress disorder, and fibromyalgia, and (4) had poorer health-related quality of life. More than half had anxiety or depressive disorders, and 93% had at least one medical and/or psychiatric diagnosis. The SF-36 predicted mental health status with a positive predictive value of 81.58. By adding the Hamilton D rating for depression, the positive predictive value increased to 88.57. INTERPRETATION: The CDC criteria accurately identified GWVs negative for GWI. Most GWVs were positive for GWI. Neither CDC criteria nor CDC severity rankings distinguish between veterans with psychiatric syndromes and those without: both groups endorsed the same symptoms. More than half of those with GWI had a treatable anxiety or depressive disorder. The SF-36 was a valid predictor of mental health status, particularly when paired with the Hamilton depression interview.


Assuntos
Síndrome do Golfo Pérsico , Veteranos , Guerra , Adulto , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Oriente Médio , Síndrome do Golfo Pérsico/diagnóstico , Síndrome do Golfo Pérsico/epidemiologia , Síndrome do Golfo Pérsico/terapia , Estatística como Assunto , Estados Unidos/epidemiologia , Veteranos/psicologia
5.
J Med Chem ; 44(21): 3343-6, 2001 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-11585438

RESUMO

Truncation of the original piperidino-2(S)-methyl piperazine lead structure 2, from a family of muscarinic antagonists, gave compound 8 which has improved selectivity for the HIV-1 co-receptor CCR5 over muscarinic receptors. Further optimization for pharmacokinetic properties afforded Sch-350634 (1), a prototypical piperazine-based CCR5 antagonist, which is a potent inhibitor of HIV-1 entry and replication in PBMCs. The title compound (1) has excellent oral bioavailability in rat, dog, and monkey.


Assuntos
Fármacos Anti-HIV/síntese química , Antagonistas dos Receptores CCR5 , Óxidos N-Cíclicos/síntese química , Piperazinas/síntese química , Administração Oral , Animais , Fármacos Anti-HIV/química , Fármacos Anti-HIV/farmacocinética , Fármacos Anti-HIV/farmacologia , Disponibilidade Biológica , Linhagem Celular , Óxidos N-Cíclicos/química , Óxidos N-Cíclicos/farmacocinética , Óxidos N-Cíclicos/farmacologia , Cães , HIV-1/efeitos dos fármacos , Técnicas In Vitro , Leucócitos Mononucleares/virologia , Macaca fascicularis , Piperazinas/química , Piperazinas/farmacocinética , Piperazinas/farmacologia , Ratos , Relação Estrutura-Atividade
6.
Nature ; 409(6819): 510-3, 2001 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-11206546

RESUMO

Hamilton's theory of kin selection suggests that individuals should show less aggression, and more altruism, towards closer kin. Recent theoretical work has, however, suggested that competition between relatives can counteract kin selection for altruism. Unfortunately, factors that tend to increase the average relatedness of interacting individuals--such as limited dispersal--also tend to increase the amount of competition between relatives. Therefore, in most natural systems, the conflicting influences of increased competition and increased relatedness are confounded, limiting attempts to test theory. Fig wasp taxa exhibit varying levels of aggression among non-dispersing males that show a range of average relatedness levels. Thus, across species, the effects of relatedness and competition between relatives can be separated. Here we report that--contrary to Hamilton's original prediction but in agreement with recent theory--the level of fighting between males shows no correlation with the estimated relatedness of interacting males, but is negatively correlated with future mating opportunities.


Assuntos
Vespas/fisiologia , Animais , Comportamento Competitivo , Feminino , Masculino , Modelos Biológicos , Dados de Sequência Molecular , Comportamento Sexual Animal , Especificidade da Espécie , Vespas/classificação , Vespas/genética
7.
Schizophr Res ; 46(2-3): 203-7, 2000 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11120432

RESUMO

In this study we examined the correlations of actual pre-morbid IQ scores (obtained from routine educational assessments) and estimated current IQ scores in 27 treatment-resistant schizophrenia patients. Pre-morbid (mean = 93) and current (mean = 83) IQ scores were significantly correlated (r = 0.807, P < 0.0001), while duration of illness (10-40 years) was unrelated to the magnitude of IQ score decline (r = -0.103, P = 0.575). These data suggest that pre-morbid IQ test scores are highly predictive of post-morbid scores.


Assuntos
Antipsicóticos/uso terapêutico , Esquizofrenia/tratamento farmacológico , Adolescente , Adulto , Método Duplo-Cego , Resistência a Medicamentos , Feminino , Humanos , Inteligência , Masculino , Pessoa de Meia-Idade , Escalas de Wechsler
8.
J Virol ; 74(22): 10430-7, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11044087

RESUMO

The hepatitis C virus (HCV) internal ribosome entry site (IRES) is a highly structured RNA element that directs cap-independent translation of the viral polyprotein. Morpholino antisense oligonucleotides directed towards stem loop IIId drastically reduced HCV IRES activity. Mutagenesis studies of this region showed that the GGG triplet (nucleotides 266 through 268) of the hexanucleotide apical loop of stem loop IIId is essential for IRES activity both in vitro and in vivo. Sequence comparison showed that apical loop nucleotides (UUGGGU) were absolutely conserved across HCV genotypes and the GGG triplet was strongly conserved among related Flavivirus and Pestivirus nontranslated regions. Chimeric IRES elements with IIId derived from GB virus B (GBV-B) in the context of the HCV IRES possess translational activity. Mutations within the IIId stem loop that abolish IRES activity also affect the RNA structure in RNase T(1)-probing studies, demonstrating the importance of correct RNA folding to IRES function.


Assuntos
Hepacivirus/metabolismo , Biossíntese de Proteínas , RNA Viral/química , RNA Viral/genética , Ribossomos/metabolismo , Regiões 5' não Traduzidas , Sequência de Bases , Linhagem Celular , Sequência Conservada , Hepacivirus/genética , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Oligonucleotídeos Antissenso/metabolismo , Filogenia , Mutação Puntual , RNA não Traduzido/química , RNA não Traduzido/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Ribonucleases/metabolismo , Transcrição Gênica , Repetições de Trinucleotídeos/genética
9.
Psychiatr Serv ; 51(3): 380-2, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10686248

RESUMO

In a sample of 104 medically stable male veterans with alcohol dependence, rates of health service utilization were compared for 48 patients with a primary diagnosis of antisocial personality disorder and 56 patients without this diagnosis. Patients were diagnosed using DSM-IV lifetime criteria; previous utilization of health services was based on self-reports. Although a similar proportion of both groups reported previous service use, patients with antisocial personality disorder reported using more substance abuse treatment services than those with a primary diagnosis of alcohol dependence. Between-group multiple regression analysis showed that an earlier age at onset of alcoholism and a history of a comorbid substance-induced mental disorder best predicted higher rates of use of substance abuse treatment.


Assuntos
Alcoolismo/complicações , Alcoolismo/terapia , Transtorno da Personalidade Antissocial/complicações , Transtorno da Personalidade Antissocial/terapia , Serviços de Saúde Mental/estatística & dados numéricos , Adolescente , Adulto , California , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Veteranos/psicologia
10.
J Infect Dis ; 181(1): 331-4, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10608783

RESUMO

Amantadine, a drug known to inhibit influenza A viral matrix (M2) protein function, was reported to be an effective treatment in some patients with chronic hepatitis C virus (HCV) infection. Sequence comparison shows no homology between M2 and any of the HCV proteins. The effects of amantadine and a related analogue, rimantadine, on viral protease, helicase, ATPase, RNA-dependent RNA polymerase, and HCV internal ribosomal entry site (IRES) translation were tested by established in vitro biochemical assays. No inhibition (>15%) of HCV protease, helicase, ATPase, and polymerase was observed with concentrations up to 400 microgram/mL. IRES-specific inhibition was not observed at clinically relevant concentrations, but both cap and IRES reporter genes were suppressed at higher levels, suggesting nonspecific translation inhibition. In conclusion, amantadine and rimantadine have no direct and specific inhibitory effects against HCV protease, helicase, ATPase, polymerase, and IRES in vitro.


Assuntos
Amantadina/farmacologia , Hepacivirus/efeitos dos fármacos , Rimantadina/farmacologia , Adenosina Trifosfatases/efeitos dos fármacos , Relação Dose-Resposta a Droga , Endopeptidases/efeitos dos fármacos , Hepacivirus/enzimologia , Biossíntese de Proteínas/efeitos dos fármacos , RNA Helicases/efeitos dos fármacos , RNA Polimerase Dependente de RNA/efeitos dos fármacos , Proteínas da Matriz Viral/genética , Proteínas Virais/genética
11.
J Mol Biol ; 292(3): 513-29, 1999 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-10497018

RESUMO

Hepatitis C virus (HCV) contains an internal ribosome entry site (IRES) located in the 5' untranslated region of the genomic RNA that drives cap-independent initiation of translation of the viral message. The approximate secondary structure and minimum functional length of the HCV IRES are known, and extensive mutagenesis has established that nearly all secondary structural domains are critical for activity. However, the presence of an IRES RNA tertiary fold and its functional relevance have not been established. Using chemical and enzymatic probes of the HCV IRES RNA in solution, we show that the IRES adopts a unique three-dimensional structure at physiological salt concentrations in the absence of additional cofactors or the translation apparatus. Folding of the IRES involves cooperative uptake of magnesium and is driven primarily by charge neutralization. This tertiary structure contains at least two independently folded regions which closely correspond to putative binding sites for the 40 S ribosomal subunit and initiation factor 3 (eIF3). Point mutations that inhibit IRES folding also inhibit its function, suggesting that the IRES tertiary structure is essential for translation initiation activity. Chemical and enzymatic probing data and small-angle X-ray scattering (SAXS) experiments in solution show that upon folding, the IRES forms an extended structure in which functionally important loops are exposed. These results suggest that the 40 S ribosomal subunit and eIF3 bind an HCV IRES that is prefolded to spatially organize recognition domains.


Assuntos
Hepacivirus/genética , RNA Viral/química , Ribossomos/genética , Sequência de Bases , Sítios de Ligação , Cátions/farmacologia , Ácido Edético/farmacologia , Compostos Ferrosos/farmacologia , Magnésio/farmacologia , Dados de Sequência Molecular , Mutação , Conformação de Ácido Nucleico , Fatores de Iniciação de Peptídeos/genética , Fator de Iniciação 3 em Procariotos , Ribonuclease T1/metabolismo , Sais , Difração de Raios X
12.
Community Ment Health J ; 35(6): 505-14, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10863987

RESUMO

Negative attitudes toward people who have serious mental illnesses held by mental health professionals threaten the effectiveness of psychiatric treatment. In this study, attitudes held by case managers working within the public sector were investigated. Differences between supportive and intensive case managers were compared with community controls using the Opinions about Mental Illness Scale. The results showed a complex interplay among client level of functioning, type of case management approach, case management philosophy, and attitudes. Among other findings, intensive case managers held more authoritarian attitudes than did their supportive case manager counterparts.


Assuntos
Atitude do Pessoal de Saúde , Administração de Caso , Transtornos Mentais/psicologia , Preconceito , Adulto , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Masculino , Relações Profissional-Paciente , Serviço Social
13.
J Neuropathol Exp Neurol ; 57(12): 1168-74, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9862640

RESUMO

The presence of diffuse or primitive senile plaques in the neocortex of cognitively normal elderly at autopsy has been presumed to represent normal aging. Alternatively, these patients may have developed dementia and clinical Alzheimer disease (AD) if they had survived. In this setting, these patients could be subjects for cognitive or pharmacologic intervention to delay disease onset. We have thus followed a cohort of cognitively normal elderly subjects with a Clinical Dementia Rating (CDR) of 0 at autopsy. Thirty-one brains were examined at postmortem according to Consortium to Establish a Registry for Alzheimer Disease (CERAD) criteria and staged according to Braak. Ten patients were pathologically normal according to CERAD criteria (1a). Two of these patients were Braak Stage II. Seven very elderly subjects exhibited a few primitive neuritic plaques in the cortex and thus represented CERAD 1b. These individuals ranged in age from 85 to 105 years and were thus older than the CERAD la group that ranged in age from 72 to 93. Fourteen patients displayed Possible AD according to CERAD with ages ranging from 66 to 95. Three of these were Braak Stage I, 4 were Braak Stage II, and 7 were Braak Stage III. The Apolipoprotein E4 allele was over-represented in this possible AD group. Neuropsychological data were available on 12 individuals. In these 12 individuals, Possible AD at autopsy could be predicted by cognitive deficits in 1 or more areas including savings scores on memory testing and overall performance on some measures of frontal executive function.


Assuntos
Envelhecimento/patologia , Doença de Alzheimer/patologia , Cognição/fisiologia , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/psicologia , Doença de Alzheimer/psicologia , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Valores de Referência , Sistema de Registros
16.
Virology ; 225(2): 328-38, 1996 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-8918919

RESUMO

The NS3 proteinase of hepatitis C virus utilizes NS4A as a cofactor for cleavages at four sites (3/4A, 4A/4B, 4B/5A, and 5A/5B) in the nonstructural region of the viral polyprotein. To characterize NS4A for its role in modulating the NS3 proteinase activity at various cleavage sites, synthetic peptides spanning various parts of NS4A were synthesized and tested in a cell-free trans-cleavage reaction using purified NS3 proteinase domain and polyprotein substrates. The NS3 proteinase domain was expressed in Escherichia coli, purified, denatured, and refolded to an enzymatically active form. We found that a 12-amino-acid peptide containing amino acid residues 22 to 33 in NS4A (CVVIVGRIVLSG) was sufficient for cofactor activity in NS3-mediated proteolysis. The peptide enhanced the cleavage at the NS5A/5B site and was necessary for NS3-mediated cleavage at NS4A/4B and NS4B/5A. Sequential amino acid substitution within the designated peptide identified residues I29 and I25 as critical for potential cofactor activity. We provide evidence that the NS4A peptide and the NS3 catalytic domain form an enzymatically active complex. These data suggest that the central 12-amino-acid peptide (aa 22-33) of NS4A is primarily important for the cofactor activity through complex formation with NS3, and the interaction may represent a new target for antiviral drug development.


Assuntos
Hepacivirus/metabolismo , Peptídeos/metabolismo , Proteínas não Estruturais Virais/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Ativação Enzimática , Humanos , Dados de Sequência Molecular , Peptídeos/química , Peptídeos/genética , RNA Helicases , Análise de Sequência , Serina Endopeptidases , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/genética
18.
J Anat ; 188 ( Pt 2): 455-72, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8621345

RESUMO

A quantitative histochemical study was made of superficial thigh muscle specimens (semimembranosus and some vastus lateralis) from topi, hartebeest, wildebeest and waterbuck (species listed in order of increasing size). Fibres were largest (up to 120 microns diameter) in waterbuck but smallest (maximum approximately 90 microns) in wildebeest. Type 2B fibres, most of them large, highly glycolytic and weakly aerobic, constituted approximately 75% of the cross-section of topi specimens and approximately 83% of the others, greater area fractions than in other large herbivores. Type 1 fibres, highly aerobic but weakly glycolytic, occupied only 2-3.5% of the area fractions, very low figures, even for these superficial sites. Type 2A fibres occupied > 20% areas in topi, approximately 15% in the other species. In waterbuck they were never more than moderately aerobic, but quite highly glycolytic; elsewhere their characteristic metabolic profiles were close to those of type 1 fibres. The 2B fractions indicate that glycolytic metabolism predominates over lipolytic in all 4 species. Mean enzymic capacities were compared semiquantitatively between species on the basis of wide-area photometric readings. Much the greatest difference was in aerobic (succinate dehydrogenase) capacities: the mean reading in topi was x 2.6 that in waterbuck, but wildebeest capacity came close to that of topi. These latter are the 2 most active species. Readings for the force-generating enzyme, actomyosin ATPase, were slightly weaker in the heavier species. This could be predicted on allometric grounds, but mass considerations appear to be overridden by behavioural differences in relation to metabolism.


Assuntos
Animais Selvagens/anatomia & histologia , Músculo Esquelético/anatomia & histologia , Ruminantes/anatomia & histologia , África Oriental , Animais , Feminino , Histocitoquímica , Masculino , Coxa da Perna
20.
AIDS Res Hum Retroviruses ; 10(3): 309-13, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8018392

RESUMO

The V3- and C4-coding regions in the envelope gene of the infectious, pathogenic SIVmac239 clone were replaced by the corresponding HIV-1 sequences. Viral particles were obtained after transfection of COS-1 cells. Chimeric SIVmac constructs were not replication competent in the human T cell lines CEMx174, AA2, H9, and MT-4 or in primary cultures of rhesus monkey peripheral blood mononuclear cells. The lack of infectivity of the hybrid constructs was associated with inefficient proteolytic processing of the gp160env precursor. Unlike the modular nature of some proteins, gp120 appears to be a highly ordered molecule whose function is dependent on the integration of many discontinuous, interactive regions.


Assuntos
Proteína gp120 do Envelope de HIV/genética , HIV-1/fisiologia , Vírus da Imunodeficiência Símia/fisiologia , Proteínas do Envelope Viral/biossíntese , Replicação Viral/fisiologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , DNA Viral , HIV-1/genética , Humanos , Dados de Sequência Molecular , Fragmentos de Peptídeos/genética , Ensaio de Radioimunoprecipitação , Proteínas Recombinantes de Fusão/genética , Vírus da Imunodeficiência Símia/genética , Vírus da Imunodeficiência Símia/imunologia , Transfecção , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/imunologia , Replicação Viral/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...