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1.
J Hum Evol ; 32(4): 323-44, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9085185

RESUMO

The African apes are a group of closely related taxa that differ considerably in body size. In spite of the large body size difference, the African apes are similar in many aspects of their morphology; it has been suggested that most of their differences result from selection for these body size differences (Shea, 1988). The influence of body size on locomotion has been well-documented, but what is less clear, is whether these behavioral differences occur throughout ontogeny because few studies have directly addressed the influence of ontogeny (and changing body size) on locomotion. This study documents the ontogeny of mountain gorilla locomotion and compares it with that of chimpanzees in order to consider how changing body size during ontogeny influences locomotion in the two species. Results indicate that gorilla locomotor development is greatly accelerated compared with chimpanzees, and that much of the interspecific variation in age can be explained by body size. When chimpanzees and gorillas are at similar sizes (although widely disparate ages), they perform very similar locomotor activities. However, it is incorrect to view a gorilla as a faster growing and ultimately larger chimpanzee. Throughout ontogeny, gorillas have broader scapulae and relatively shorter phalanges and metacarpals than chimpanzees (Susman, 1979; Shea, 1981; Jungers & Susman, 1984; Inouye, 1992) which are associated differences in mountain gorilla and chimpanzee suspensory behavior; gorillas never show as high an incidence of suspensory behavior as chimpanzees during ontogeny.


Assuntos
Envelhecimento/fisiologia , Gorilla gorilla/fisiologia , Locomoção , Pan troglodytes/fisiologia , Animais , Constituição Corporal , Feminino , Gorilla gorilla/anatomia & histologia , Masculino , Menarca , Atividade Motora , Pan troglodytes/anatomia & histologia , Caracteres Sexuais , Especificidade da Espécie
2.
Am J Phys Anthropol ; 91(1): 99-115, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8512057

RESUMO

Focal animal instantaneous sampling of adult male and female chimpanzee positional behavior was conducted during a 7-month study in the Tai Forest, Ivory Coast, in order to determine whether there are sex differences in the locomotion, posture, substrate use, and height preference of sexually dimorphic adult chimpanzees, and if so, whether these differences support predictions based on body size differences. Results indicate that as predicted, adult male and female chimpanzees differ in their arboreal locomotor behavior, with the larger males using less quadrupedalism and more climbing, scrambling, and aided bipedalism than females during feeding locomotion. There is a sex difference in height preference as well, with female chimpanzees consistently using more arboreal behavior than males, primarily during resting. Although it has been previously demonstrated that separate primate species of differing body size differ in locomotor and postural activities (Fleagle and Mittermeier, 1980; Crompton, 1984), this study clearly demonstrates that body size differences within a species can also be correlated with differences in locomotor behavior. These findings may influence how we interpret sex differences in body size of extinct species.


Assuntos
Constituição Corporal/fisiologia , Atividade Motora/fisiologia , Pan troglodytes/fisiologia , Postura/fisiologia , Caracteres Sexuais , Animais , Feminino , Masculino , Pan troglodytes/anatomia & histologia
3.
Am J Phys Anthropol ; 91(1): 83-98, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8512056

RESUMO

Results from a 10 month study of adult male and female bonobos (Pan paniscus) in the Lomako Forest, Zaire, and those from a 7 month study of adult male and female chimpanzees in the Tai Forest, Ivory Coast (Pan troglodytes verus), were compared in order to determine whether there are species differences in locomotor behavior and substrate use and, if so, whether these differences support predictions made on the basis of interspecific morphological differences. Results indicate that bonobos are more arboreal than chimpanzees and that male bonobos are more suspensory than their chimpanzee counterpart. This would be predicted on the basis of male bonobo's longer and more narrow scapula. This particular finding is contrary to the prediction that the bonobo is a "scaled reduced version of a chimpanzee" with little or no positional behavior difference as had been suggested. This study provides the behavioral data necessary to untangle contradictory interpretations of the morphological differences between chimpanzees and bonobos, and raises a previously discussed (Fleagle: Size and Scaling in Primate Biology, pp. 1-19, 1985) but frequently overlooked point--that isometry in allometric studies does not necessarily equate with behavioral equivalence. Several researchers have demonstrated that bonobos and chimpanzees follow the same scaling trends for many features, and are in some sense functionally equivalent, since they manage to feed and reproduce. However, as reflected in their morphologies, they do so through different types and frequencies of locomotor behaviors.


Assuntos
Atividade Motora/fisiologia , Pan troglodytes/fisiologia , Animais , Feminino , Comportamento de Retorno ao Território Vital , Masculino , Pan troglodytes/anatomia & histologia , Especificidade da Espécie
4.
Am J Phys Anthropol ; 89(1): 85-99, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1530064

RESUMO

Currently two methods, instantaneous and locomotor bout sampling, are used most commonly in studies of locomotor behavior. To date, no study has addressed how comparable the results of the two methods are. This paper considers whether different sampling methods of locomotor behavior produce different results. Continuous locomotor bout and instantaneous sampling were carried out simultaneously on each focal animal during a seven month study of chimpanzee positional behavior in the Tai Forest of the Ivory Coast. Results provide two independent sets of data which describe the same events. Results indicate that as locomotor bouts are frequently presented (the percentage of bouts spent in an activity), they overrepresent the frequencies of activities that occur relatively often, but for short distances, and underrepresent activities that have a relatively large mean distance per bout. However, when bouts are weighted with distance, as originally defined by Fleagle (1976b), there are no significant differences in the results obtained by the two methods. Both provide similar results for the frequencies of locomotor activities, frequency of substrate use, and the relationship between substrate and locomotor activity. The advantage of instantaneous sampling is that because it is done at regular intervals, it can easily be carried out in conjunction with sampling other behavioral and ecological data. The advantages of locomotor bout sampling are that it permits the sampling of rare or brief locomotor events and allows for an analysis of sequences of locomotor activities. This paper demonstrates that the two methods can be conducted simultaneously and thus provide the richest return from which the effect of environment and morphology on locomotion can be addressed.


Assuntos
Locomoção , Atividade Motora , Pan troglodytes/fisiologia , Animais , Comportamento Animal , Coleta de Dados , Comportamento Alimentar , Masculino , Árvores
5.
Nature ; 356(6372): 799-801, 1992 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-1574119

RESUMO

The CD4 and CD8 molecules are transmembrane glycoproteins expressed by functionally distinct subsets of mature T cells. CD4+ and CD8+ T cells recognize antigens on major histocompatibility complex (MHC) class II-bearing and class I-bearing target cells respectively. The ability of monoclonal antibodies against CD4 and CD8 to block antigen recognition by T cells, as well as cell-cell adhesion assays, indicate that CD4 and CD8 bind to nonpolymorphic determinants of class II or class I MHC. Here we demonstrate that soluble recombinant HLA-DR4 molecules from insect cells and HLA-DR-derived peptides bind to immobilized recombinant soluble CD4. CD4 binds recombinant soluble DR4 heterodimers, as well as the soluble DR4-beta chain alone. Furthermore, two out of twelve DR4-beta peptides could interact specifically with CD4. These findings show that CD4 interacts with a region of MHC class II molecules analogous to a previously identified loop in class I MHC proteins that binds CD8 (refs 8, 9).


Assuntos
Antígenos CD4/metabolismo , Antígeno HLA-DR4/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Cromatografia de Afinidade , Immunoblotting , Técnicas In Vitro , Insetos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Proteínas Recombinantes/metabolismo , Especificidade por Substrato
7.
Nature ; 336(6201): 778-80, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-2462673

RESUMO

An ideal vaccine should elicit a long lasting immune response against the natural parasite, both at the T- and B-cell level. The immune response should occur in all individuals and be directed against determinants that do not vary in the natural parasite population. A major problem in designing synthetic peptide vaccines is that T cells generally recognize peptide antigens only in association with one or a few of the many variants of major histocompatibility complex (MHC) antigens. During the characterization of epitopes of the malaria parasite Plasmodium falciparum that are recognized by human T cells, we analysed a sequence of the circumsporozoite protein, and found that synthetic peptides corresponding to this sequence are recognized by T cells in association with many different MHC class II molecules, both in mouse and in man. This region of the circumsporozoite protein is invariant in different parasite isolates. Peptides derived from this region should be capable of inducing T-cell responses in individuals of most HLA-DR types, and may represent good candidates for inclusion in an effective anti-malaria peptide vaccine.


Assuntos
Antígenos de Protozoários/imunologia , Antígenos de Histocompatibilidade Classe II , Malária/imunologia , Plasmodium falciparum/imunologia , Linfócitos T/imunologia , Sequência de Aminoácidos , Animais , Epitopos , Humanos , Camundongos , Dados de Sequência Molecular
8.
Eur J Immunol ; 18(4): 633-6, 1988 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2452748

RESUMO

The circumsporozoite protein of the malaria parasite Plasmodium falciparum contains regions of nonrepetitive sequences which are predicted to be T cell recognition sites. We synthesized peptides corresponding to three of these regions, and tested their ability to stimulate proliferation of peripheral blood lymphocytes from donors living in a malaria-endemic area, or from nonimmune donors. Cells from 15 out of 22 donors (including 4 of 6 nonimmune individuals) were stimulated by one or more of the peptides. T cell clones specific for one of the peptides were obtained and shown to recognize the native protein purified from sporozoites. These data help to identify T cell epitopes which could be incorporated into a malaria vaccine.


Assuntos
Antígenos de Superfície/imunologia , Plasmodium falciparum/imunologia , Proteínas de Protozoários , Linfócitos T/imunologia , Animais , Células Clonais , Epitopos , Humanos , Ativação Linfocitária
9.
J Reprod Immunol ; 9(3): 205-12, 1986 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3806528

RESUMO

Natural killer cell activity and antibody dependent cell-mediated cytotoxicity (NK and ADCC) of peripheral blood lymphocytes were measured against K-562 and antibody coated HSB target cells with a 4-h chromium release assay in 19 primigravidas with preeclampsia. Nineteen primigravidas with an uncomplicated pregnancy and 19 nonpregnant women served as controls. Lymphocyte NK and ADCC activities are significantly lower in primigravidas than in nonpregnant women. Primigravidas with preeclampsia have similar cell-mediated cytotoxic activities to primigravidas with an uncomplicated pregnancy. These findings support the hypothesis that maternal acceptance of the fetal-allograft is due to suppression of cell-mediated cytotoxicity. Altered cellular cytotoxicity appears unlikely as a cause of preeclampsia. Our results, however, do not preclude local changes in cellular immune activities that may occur at the implantation site.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos , Células Matadoras Naturais/imunologia , Pré-Eclâmpsia/imunologia , Feminino , Humanos , Gravidez , Transtornos Puerperais/imunologia , Valores de Referência
10.
Lancet ; 1(8388): 1212-4, 1984 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-6144926

RESUMO

A network of idiotypic and anti-idiotypic antibodies is often suggested as the basis for cellular interactions that maintain a steady-state immunological equilibrium. This hypothesis proposes that repeated exposure to certain external antigens--ie, both viral and sperm--stimulates an unregulated production of a uniquely potent immunomodulating idiotypic antibody(ies). In a genetically predisposed individual, this particular antibody(ies), which is also an autoantibody(ies), results in a cellular immune deficiency. This disruption in the immune system permits opportunistic infection and thus the acquired immune deficiency syndrome. This hypothesis, which is readily testable and which does not involve a primary pathogen, can explain both the active induction of this disease in, as well as its passive transfer to, all at-risk populations.


Assuntos
Síndrome da Imunodeficiência Adquirida/etiologia , Anticorpos Anti-Idiotípicos/biossíntese , Anticorpos Antivirais/imunologia , Idiótipos de Imunoglobulinas/imunologia , Espermatozoides/imunologia , Síndrome da Imunodeficiência Adquirida/imunologia , Síndrome da Imunodeficiência Adquirida/transmissão , Especificidade de Anticorpos , Homossexualidade , Humanos , Masculino , Modelos Biológicos
11.
Obstet Gynecol ; 61(6): 737-42, 1983 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6189035

RESUMO

Many of the components of amniotic fluid have been found to be valuable in prenatal diagnosis; however, the presence of erythrocytes is usually considered undesirable. The authors have used buoyant density centrifugation on 96 amniotic fluid specimens from 70 subjects to isolate small numbers of erythrocytes from a majority of these specimens. Through immunofluorescence, these specimens were found to have higher levels of fetal hemoglobin-containing cells than the adult, indicating that the erythrocytes were at least in part fetal in origin. Thus, erythrocytes present in amniotic fluid could also be used in prenatal diagnosis.


Assuntos
Amniocentese , Líquido Amniótico/citologia , Eritrócitos/análise , Hemoglobina Fetal/análise , Separação Celular/métodos , Feminino , Imunofluorescência , Humanos , Gravidez
12.
Tissue Antigens ; 19(1): 53-9, 1982 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7071816

RESUMO

A Black American family of four generations with 29 members was studied. Six family members spanning two generations were affected with myotonic dystrophy. HLA A, B, C and DR antigen specificities were determined for each family member using local typing trays. Twelve HLA haplotypes were identified in the family. No significant association was found between the disease and any HLA antigenic type or haplotype. This finding suggests that the involvement of the major histocompatibility complex in the etiology of myotonic dystrophy is unlikely. The cellular responses to twenty-eight family members and 20 unrelated Black Americans to phytohemagglutinin (PHA), Concanavalin A (Con A) and pokeweed mitogen (PWM), each in three concentrations, were tested with mononuclear cells prepared from peripheral blood. There was a significant difference in responses of the affected family members as compared to the unaffected family members and the unrelated Black Americans. The PHA and PWM responses of the unaffected family members are not significantly different from those of the unrelated Black American controls; however, the Con A responses of the unaffected family members are significantly higher than those of the control group at the lowest Con A dosage. The possible systemic defects of cytoskeletal structures of the affected family members are discussed.


Assuntos
Antígenos HLA , Ativação Linfocitária , Distrofia Miotônica/imunologia , População Negra , Feminino , Antígenos HLA/genética , Humanos , Masculino , Mitógenos/farmacologia , Distrofia Miotônica/genética , Linhagem
13.
J Immunol Methods ; 39(1-2): 155-63, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-7462645

RESUMO

The iodine monochloride (IC1) technique is used to radiolabel proteins under mild experimental conditions. Proteins labeled by this technique have been shown to have both in vitro in vivo characteristics often superior to those proteins labeled by the more frequently used chloramine-T method. Although first published more than two decades ago, use of the IC1 technique has largely been superceded by other more recently developed iodination methods. This paper attempts to reintroduce th oxidative IC1 method to the research community. This is accomplished by the presentation of a detailed protocol for a convenient modification of the original technique. A review of the qualities of the iodinated proteins produced by the IC1 and other iodination methods is also discussed.


Assuntos
Iodoproteínas/síntese química , Humanos , Iodetos , Radioisótopos do Iodo , Métodos , Albumina Sérica/metabolismo
14.
Proc Natl Acad Sci U S A ; 76(11): 5631-5, 1979 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-392508

RESUMO

Escherichia coli strain chi 1776 carrying recombinant DNA plasmids containing cDNA copies of human beta or gamma globin mRNAs has been shown by radioimmunoassay to synthesize polypeptides antigenically related to the beta and gamma chains of human hemoglobin. The gamma and beta polypeptides have been enriched from lysates on immunoabsorbent columns containing hemoglobin antibodies and shown to specifically inhibit the antigen-antibody binding between 125I-labeled hemoglobin and the homologous antibody but not other hemoglobin-antihemoglobin reactions. Clone JW151, which is known to contain a complete copy of the coding portion of the gamma globin mRNA, has been shown to produce a protein that reacts specifically with antibody to the chain of fetal hemoglobin, hemoglobin Kenya, and hemoglobin Bart's.


Assuntos
DNA Recombinante , Globinas/genética , Sequência de Bases , Enzimas de Restrição do DNA/metabolismo , Escherichia coli/genética , Genes , Ligação Genética , Globinas/análise , Humanos , Plasmídeos , Radioimunoensaio
15.
Rheumatol Rehabil ; 18(3): 188-9, 1979 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-493807

RESUMO

A case of myositis ossificans, following a hemiparesis due to a cerebral haemorrhage and treated with synthetic slamon calcitonin, is described. An improvement in joint range and a cessation of further ectopic calcification was seen but, because of the remitting nature of myositis ossificans itself, the therapeutic role of calcitonin in this case is unproven.


Assuntos
Calcitonina/uso terapêutico , Miosite Ossificante/tratamento farmacológico , Feminino , Humanos
16.
Br Med J ; 2(5964): 161-4, 1975 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-123815

RESUMO

In a multicentre trial 456 selected patients with low back pain were randomly allocated to one of four treatments-manipulation, definitive physiotherapy, corset, or analgesic tablets. Patients were reassessed clinically after three weeks' treatment and again after a further three weeks. Questionnaires were used to find out the patients' condition three months and one year after admission to the trial. There were never any important differences among the four groups of patients. A few patients responded well and quickly to manipulation, but there was no way of identifying such patients in advance. The response to a corset was slow, but the long-tern effects were at least as good as those of the other treatments. Patients treated only with analgesics fared marginally worse than those on the other three treatments. There is no strong reason, however, for recommending manipulation over physiotherapy or corset.


Assuntos
Dor nas Costas/terapia , Acetaminofen/uso terapêutico , Adulto , Dor nas Costas/tratamento farmacológico , Ensaios Clínicos como Assunto , Feminino , Seguimentos , Humanos , Imobilização , Masculino , Manipulação Ortopédica , Pessoa de Meia-Idade , Modalidades de Fisioterapia , Inquéritos e Questionários , Fatores de Tempo
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