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1.
J Immigr Minor Health ; 15(3): 472-5, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22752660

RESUMO

Colorectal cancer screening (CRC) disparities between non-Latino Whites and Latinos remain, and may have increased. The goal of this analysis was to examine the association between Latino race/ethnicity, gender, and English-proficiency and CRC screening. Analysis of the CDC's BRFSS 2008 survey. We estimated crude and adjusted screening rates and odds ratios of respondents' reported CRC test receipt stratified by self-reported Latino ethnicity, gender, and limited English proficiency (LEP) as determined by language of survey response (English vs Spanish). Of 99,883 respondents included in the study populations, LEP Latino men had the lowest adjusted screening rates (48.2%) which were lower that all other Latinos subgroups including Latina women with LEP (56.2%). Compared to non-Latino White men, LEP Latino men were 0.47 times as likely to report receiving CRC screening tests (AOR 0.47; 95% CI 0.35-0.63). Disparities in CRC screening are most dramatic for LEP Latino men.


Assuntos
Neoplasias Colorretais/diagnóstico , Barreiras de Comunicação , Hispânico ou Latino , Idioma , Programas de Rastreamento , Fatores Sexuais , Idoso , Intervalos de Confiança , Detecção Precoce de Câncer , Feminino , Pesquisas sobre Atenção à Saúde , Disparidades em Assistência à Saúde , Humanos , Masculino , Programas de Rastreamento/estatística & dados numéricos , Pessoa de Meia-Idade , Estados Unidos
2.
Value Health ; 14(4): 555-63, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21669380

RESUMO

OBJECTIVES: The purpose of our study was to use health-related quality of life data from the Women's Health Initiative to calculate health-related utility weights and examine differences in these health utility weights across different hemoglobin (Hgb) levels. These utility weights could then be used in future cost-effectiveness studies. METHODS: Health utility weights were measured by the Short Form-6D (SF-6D), a health utility index derived from the Short Form Medical Outcomes questionnaire. Adjusted least square means were calculated for each level of Hgb at baseline and in longitudinal regression analysis the relationship between change in Hgb and change in the SF-6D was examined. Both baseline and longitudinal analyses were performed for all postmenopausal women and separately for those with self-reported heart failure, cancer, and osteoarthritis. RESULTS: Women with Hgb in the anemic range had lower health utility weights than those with higher Hgb levels. Longitudinally, a loss of of 2 g/dl Hgb or more was associated with a statistically significant and clinically meaningfully decline in SF-6D in all participants and also in the group of participants with cancer and osteoarthritis, but not in those with heart failure. CONCLUSIONS: Lower levels of Hgb and a loss of Hgb are associated with a statistically significant and clinically meaningful decrement in health utility in all postmenopausal women we studied and also in those with chronic conditions.


Assuntos
Indicadores Básicos de Saúde , Hemoglobinas/metabolismo , Pós-Menopausa/sangue , Qualidade de Vida , Saúde da Mulher , Idoso , Anemia/sangue , Anemia/diagnóstico , Anemia/psicologia , Contagem de Células Sanguíneas/métodos , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Pós-Menopausa/psicologia , Qualidade de Vida/psicologia , Inquéritos e Questionários
3.
Hum Reprod ; 26(9): 2518-24, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21677061

RESUMO

BACKGROUND: American Samoa and Samoa are now characterized by one of the world's highest levels of adult overweight and obesity. Our objective was to investigate patterns of menstrual cyclicity reported by Samoan women and examine the relationship to adiposity and select hormone levels. METHODS: A cross-sectional analysis was performed among Samoan women, aged 18-39 years (n = 322), using anthropometric and biomarker measures of adiposity and reproductive health, including insulin, adiponectin, testosterone, sex hormone-binding globulin, free androgen index (FAI) and mullerian-inhibiting substance (MIS). Menstrual regularity was assessed from self-reported responses. Multivariable models were estimated to adjust for potential confounding of the associations between menstrual patterns and other measures. RESULTS: A high proportion of the women (13.7%) reported oligomenorrhea or amenorrhea (OM/AM). More than three-quarters, 80.7%, of women were either overweight or obese, using Polynesian-specific criteria, and OM/AM was significantly associated with higher BMI. Abdominal circumference and insulin levels were significantly higher, and adiponectin levels were lower, in those who reported OM/AM versus regular menstruation. The FAI was higher in women with increased BMI. MIS levels declined with age, more slowly in those reporting OM/AM. CONCLUSIONS: Self-reported OM/AM was associated with an elevated BMI, abdominal adiposity and serum insulin, and with reduced adiponectin levels. These findings support a high rate of metabolic syndrome, and perhaps PCOS and reproductive dysfunction, among Samoan women.


Assuntos
Ciclo Menstrual/fisiologia , Distúrbios Menstruais/etiologia , Obesidade/fisiopatologia , Adiponectina/sangue , Adiposidade , Adolescente , Adulto , Fatores Etários , Hormônio Antimülleriano/metabolismo , Estudos Transversais , Feminino , Humanos , Insulina/sangue , Análise Multivariada , Obesidade/complicações , Obesidade/epidemiologia , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/epidemiologia , Fatores de Risco , Samoa/epidemiologia , Globulina de Ligação a Hormônio Sexual/metabolismo , Testosterona/sangue
4.
J Hum Evol ; 59(5): 493-503, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20828787

RESUMO

In 1995-1996 two isolated hominin lower incisors were found at the middle Pleistocene site of Boxgrove in England, with Lower Palaeolithic archaeology. Boxgrove 2 is a permanent lower right central incisor and Boxgrove 3 a permanent lower left lateral incisor. They were found separately, but close to one another and appear to belong to the same individual. The Boxgrove 1 tibia discovered in 1993 came from a different stratigraphic context and is thus believed to represent a different individual. This paper describes the morphology of the incisors, which is similar to other middle Pleistocene hominin specimens and, as with the tibia, suggests that they could be assigned to Homo heidelbergensis (recognising that the taxonomic status of this species is still a matter of debate). The incisors show substantial attrition associated with secondary dentine deposition in the pulp chamber and clearly represent an adult. They also show extensive patterns of non-masticatory scratches on the labial surfaces of both crown and root, including some marks which may have been made postmortem. The roots were exposed in life on their labial sides by a large dehiscence, extending almost to the root apex. This is demonstrated by deposits of calculus, polishing, and scratching on the exposed surfaces. The dehiscence may have been caused by repeated trauma to the gingivae or remodelling of the tooth-supporting tissues in response to large forces applied to the front of the dentition.


Assuntos
Fósseis , Hominidae/anatomia & histologia , Incisivo/anatomia & histologia , Adulto , Animais , Cálculos Dentários , Inglaterra , Humanos , Incisivo/patologia , Microscopia Eletrônica de Varredura , Desgaste dos Dentes
5.
J Hum Evol ; 40(4): 331-8, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11312585

RESUMO

Histomorphometric analysis of a medial midshaft chip from the Middle Pleistocene (ca. 500 ka BP) hominid tibia from Boxgrove, U.K. provides a modal age-at-death estimate at the end of the fourth decade of life. This makes Boxgrove 1 one of the older known and systematically aged Middle Pleistocene hominid specimens, and it reinforces the pattern of an underrepresentation of older adults observed in Middle and Late Pleistocene archaic Homo samples.


Assuntos
Determinação da Idade pelo Esqueleto/métodos , Determinação da Idade pelo Esqueleto/veterinária , Fósseis , Hominidae/anatomia & histologia , Animais , Diáfises/anatomia & histologia , Humanos , Tíbia/anatomia & histologia
6.
J Hum Evol ; 37(1): 1-25, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10375475

RESUMO

Cross-sectional geometric analysis of the early Middle Pleistocene human tibia from Boxgrove, West Sussex, U.K. reveals a mosaic pattern relative to other archaic Homo tibiae. The specimen has relatively low percent cortical area within its cross sections. However, it exhibits the high mediolateral strength characteristic of archaic Homo tibiae. Scaled solely to tibial length it is robust, similar to those of the Neandertals and above those of early modern and pre-Late Pleistocene African and Asian humans. However, given ecogeographically-patterned variance in relative tibial length and body laterality, it is most likely that it exhibits a level of robusticity within the range encompassed by Late Pliocene to Late Pleistocene archaic Homo combined with arctic body proportions. Given its association with late interglacial cool temperate climatic indicators, the inferred body proportions of the Boxgrove hominid were probably promoted by their minimal level of cultural buffering, requiring a significant biological conservation of body heat.


Assuntos
Fósseis , Hominidae/anatomia & histologia , Tíbia/anatomia & histologia , Animais , Antropologia Física , Fenômenos Biomecânicos , Constituição Corporal , Clima Frio , Hominidae/fisiologia , Humanos , Modelos Biológicos , Tíbia/fisiologia , Tomografia Computadorizada por Raios X/métodos , Reino Unido
8.
J Hum Evol ; 34(5): 509-47, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9614636

RESUMO

The Boxgrove tibia was discovered in 1993, associated with Middle Pleistocene fauna, and Lower Palaeolithic archaeology. The sediments at Boxgrove were deposited during a temperate interglacial episode and ensuing cold stage. They thus represent a wide range of modes and environments of deposition. Archaeological remains have been excavated from all the major stratigraphic units, giving a continuity of occupation for this part of southern England over a 10(4) year timescale, through markedly changing climatic regimes. The stratigraphic, archaeological and sedimentological contexts of the tibia are described, as well as its preservation and morphology. Measurements are given, with discussion of reconstructed bone length, and stature estimates. Comparative measurements are provided for fossil and recent human samples: the large dimensions of its diaphysis place the Boxgrove tibia near or beyond the upper size limits of the comparative samples, but its reconstructed length and estimated stature are less exceptional. The elevated robusticity of the specimen indicates exceptional diaphyseal strength and/or cold adapted body proportions paralleling those of the Neanderthals. Disagreement about the taxonomy of Middle Pleistocene hominids and lack of comparable fossil material make a specific assignment for the Boxgrove tibia problematic. The tibia can only definitely be assigned to non-modern Homo sp., with possible further reference to Homo cf. heidelbergensis (Schoetensack, 1908) on temporal and geographic grounds, if the validity of that species is accepted.


Assuntos
Hominidae/anatomia & histologia , Tíbia/anatomia & histologia , Animais , Fósseis , Humanos , Paleontologia , Reino Unido
9.
Am J Health Promot ; 12(4): 246-53, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10178617

RESUMO

PURPOSE: This study compares the efficacy of a self-help intervention tailored to the individual's stage of motivational readiness for exercise adoption with a standard self-help exercise promotion intervention. DESIGN: Interventions were delivered at baseline and 1 month; assessments were collected at baseline and 3 months. SETTING: Eleven worksites participating in the Working Healthy Research Trial. SUBJECTS: Participants (n = 1559) were a subsample of employees at participating worksites, individually randomized to one of two treatment conditions. INTERVENTION: Printed self-help exercise promotion materials either (1) matched to the individual's stage of motivational readiness for exercise adoption (motivationally tailored), or (2) standard materials (standard). MEASURES: Measures of stage of motivational readiness for exercise and items from the 7-Day Physical Activity Recall. RESULTS: Among intervention completers (n = 903), chi-square analyses showed that, compared to the standard intervention, those receiving the motivationally tailored intervention were significantly more likely to show increases (37% vs. 27%) and less likely to show either no change (52% vs. 58%) or regression (11% vs. 15%) in stage of motivational readiness. Multivariate analyses of variance showed that changes in stage of motivational readiness were significantly associated with changes in self-reported time spent in exercise. CONCLUSIONS: This is the first prospective, randomized, controlled trial demonstrating the efficacy of a brief motivationally tailored intervention compared to a standard self-help intervention for exercise adoption. These findings appear to support treatment approaches that tailor interventions to the individual's stage of motivational readiness for exercise adoption.


Assuntos
Exercício Físico/psicologia , Promoção da Saúde/métodos , Motivação , Saúde Ocupacional , Adulto , Análise de Variância , Feminino , Humanos , Masculino , Análise de Regressão , Rhode Island
10.
J Immunol ; 160(4): 1992-9, 1998 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-9469463

RESUMO

In a case-control study based in two areas of Kenya, hepatosplenic schistosomiasis mansoni was shown to be linked with low levels of IL-5 and with correspondingly high IFN-gamma, TNF, and circulating soluble TNF receptor I (sTNFR-I), sTNFR-II, and sICAM-1. PBMC from the hepatosplenic cases responded to in vitro Ag stimulation with significantly higher levels of IFN-gamma and TNF, but lower levels of IL-5, compared with nonhepatosplenic controls matched for age and infection intensity. Most of these correlations were confounded by differences between geographical areas. However, principle component analysis identified a high IFN-gamma and TNF, and low IL-5 axis in the data as the first principle component; this was significantly associated with hepatosplenomegaly (p < 0.0005) even after controlling for area. High plasma levels of sTNFR-I (p < 0.001), sTNFR-II, (p < 0.0001), and sICAM-1 (p < 0.009) were also significantly associated with hepatosplenomegaly, independently of area, in the case of the soluble forms of both TNF receptors. These parameters were negatively related to IL-5. These results suggest that proinflammatory cytokines are involved in the hepatosplenic disease process in infected individuals who have low anti-inflammatory Th2 responses and that sTNFR may be a useful circulating marker for this disease process, perhaps reflecting the level of TNF activity in hepatic tissues.


Assuntos
Molécula 1 de Adesão Intercelular/sangue , Interferon gama/sangue , Interleucina-5/sangue , Hepatopatias Parasitárias/imunologia , Receptores do Fator de Necrose Tumoral/sangue , Esquistossomose mansoni/imunologia , Esplenopatias/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Adolescente , Biomarcadores/sangue , Estudos de Casos e Controles , Criança , Citocinas/biossíntese , Citocinas/sangue , Feminino , Humanos , Hepatopatias Parasitárias/patologia , Masculino , Esquistossomose mansoni/patologia , Esplenopatias/parasitologia , Esplenopatias/patologia
11.
Ann Behav Med ; 20(3): 174-80, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9989324

RESUMO

This study compared the efficacy of two low-cost interventions for physical activity adoption. Sedentary (N = 194) adults recruited through newspaper advertisements were randomized to receive either a motivationally-matched, individually-tailored intervention (IT) or a standard self-help intervention (ST). Assessments and interventions were delivered by repeated mailings at baseline, one, three, and six months. Participants were assessed regarding current physical activity behavior, motivational readiness to adopt regular physical activity, and psychological constructs associated with physical activity participation (e.g. self-efficacy, decisional balance). Repeated measures analyses of variance (ANOVAs) revealed significant increases in physical activity participation between baseline and six months for both groups with a significantly greater increase among IT participants. The IT group outperformed the ST group on all primary outcome measures: (a) minutes of physical activity per week, (b) reaching Centers for Disease Control and American College of Sports Medicine (CDC/ACSM) recommended minimum physical activity criteria, and (c) achieving the Action stage of motivational readiness for physical activity adoption. Both groups showed significant improvement between baseline and six months on the psychological constructs associated with physical activity adoption (e.g. self-efficacy), with no significant differences observed between the treatment groups. Utilizing computer expert systems and self-help manuals to provide individually-tailored, motivationally-matched interventions appears to be an effective, low-cost approach for enhancing physical activity participation in the community.


Assuntos
Motivação , Atividade Motora , Adulto , Feminino , Humanos , Masculino , Apoio Social , Inquéritos e Questionários , Fatores de Tempo
12.
Nature ; 369(6478): 311-3, 1994 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-8183368

RESUMO

Fossil hominids from the earlier Middle Pleistocene of Europe are very rare and the Mauer mandible is generally accepted as the most ancient, with an estimated age of 500 kyr. We report here on the discovery of a human tibia, in association with stone tools, from calcareous silts at the Lower Palaeolithic site of Boxgrove, West Sussex, UK (Fig. 1). The silt units are correlated by mammalian biostratigraphy to an, as yet unnamed, major temperate stage or interglacial that immediately pre-dates the Anglian cold stage. Accordingly, the temperate sediments are equated with oxygen isotope stage 13 (ref. 6) and are therefore roughly coeval with the Mauer mandible. The massive tibia is the oldest hominid fragment from the British Isles and provides the first information about the manufacturers of the early Acheulian industries of Europe. It is assigned to Homo cf. heidelbergensis.


Assuntos
Fósseis , Hominidae/anatomia & histologia , Tíbia/anatomia & histologia , Animais , Arqueologia , Evolução Biológica , Clima , Humanos , Reino Unido
14.
Eur J Immunol ; 17(11): 1669-72, 1987 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3479333

RESUMO

On a B10 genetic background noncure and cure phenotypes for murine visceral leishmaniasis are controlled by H-2. In this report results are presented which show the effects of administering specific anti-I-A and anti-I-E monoclonal antibodies to B10.D2/n (H-2d) noncure mice prior to and during 85 days of infection with Leishmania donovani LV9. The effects of the two anti-Ia antibodies were precisely equivalent in diminishing circulating anti-leishmanial IgG levels throughout infection, possibly as a direct effect of the anti-Ia antibodies in reducing the splenic B cell population. In terms of resolution of liver and spleen parasite loads, which is known to be dependent upon induction of a cell-mediated immune response, dramatically different results were obtained with the two anti-Ia antibodies. Anti-I-A treatment resulted in prolonged exacerbation of disease in liver and spleen. Anti-I-E treatment was associated with enhanced clearance of liver and spleen parasite loads beyond 30 days of infection. The results are consistent with the hypothesis that blocking major histocompatibility complex-restricted antigen presentation by one class II molecule allows T cell responses controlled by the other to predominate. Hence, in H-2d mice, I-E controls suppressor activity while I-A is associated with helper activity for cell-mediated control of infection. The results offer some prospect for the development of haplotype- and class II molecule-specific immunotherapeutic regimens in the host which might prevent the undesirable expansion of T cell populations which exacerbate disease without compromising development of a curative cell-mediated immune response.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antígenos de Histocompatibilidade Classe II/imunologia , Leishmaniose Visceral/terapia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Antiprotozoários/biossíntese , Feminino , Imunoglobulina G/biossíntese , Leishmania donovani/isolamento & purificação , Leishmaniose Visceral/parasitologia , Fígado/parasitologia , Camundongos , Camundongos Endogâmicos/imunologia , Baço/parasitologia
17.
J Exp Med ; 162(1): 324-31, 1985 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-3891904

RESUMO

We have examined the relative roles of the macrophage (M phi) plasma membrane receptor for the cleaved third complement component (iC3b, CR3) and of the mannosyl/fucosyl receptor (MFR) in binding and ingestion of Leishmania donovani. In the absence of exogenous complement, the binding and ingestion of promastigotes, which are good activators of the alternative complement pathway, were inhibited by the anti-CR3 monoclonal antibody M1/70, by the Fab portion of an anti-C3 antibody, or by the nucleophile, sodium salicyl hydroxamate, an inhibitor of C3 fixation. This provides strong evidence that M phi-derived, cleaved C3 (iC3b) present on the promastigote surface mediates binding to CR3. Equivalent inhibition of promastigote binding and ingestion was also observed using the soluble inhibitors of MFR activity, mannan or ribonuclease B. No additive effect for blocking the two M phi receptors simultaneously was observed. For amastigotes, which are poor activators of the alternative pathway, a lesser but nevertheless equivalent effect was observed for the three soluble inhibitors of CR3-mediated binding vs. the two soluble inhibitors of MFR-mediated binding. Modulation experiments in which either CR3 or MFR had been rendered inaccessible demonstrated that both receptors must be present on the segment of M phi membrane to which the parasite binds. The combined function of these two distinct M phi receptors may provide a general mechanism for recognition and ingestion of other pathogenic protozoa known to activate the alternative pathway.


Assuntos
Lectinas Tipo C , Leishmania/imunologia , Macrófagos/imunologia , Lectinas de Ligação a Manose , Receptores de Superfície Celular , Receptores de Complemento/imunologia , Receptores Mitogênicos/imunologia , Animais , Sítios de Ligação , Feminino , Técnicas In Vitro , Antígeno de Macrófago 1 , Macrófagos/parasitologia , Masculino , Receptor de Manose , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Opsonizantes/imunologia , Receptores Imunológicos/imunologia
18.
Immunogenetics ; 21(4): 385-95, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3997209

RESUMO

The courses of visceral infection following intravenous injection of Leishmania donovani amastigotes, or lesion growth following subcutaneous injection of L. major promastigotes, were examined in B10.129(10M) (H-2b, H-11b) mice and compared with disease profiles observed in congenic C57BL/10ScSn(= B10) (H-2b, H-11a) and B10.D2/n (H-2d, H-11a) mice, and in BALB/mice. Possession of alternative alleles at H-11 and closely linked loci transformed the normal curing/healing phenotype of B10 mice into a characteristically different noncuring/nonhealing phenotype affecting both visceral and subcutaneous infections in B10.129(10M) mice. In reciprocal radiation bone marrow chimeras made between the congenic B10 and B10.129(10M) strains, both cure and noncure phenotypes were transferable with the donor hematopoietic system. Although it was possible to demonstrate transfer of suppression with T-enriched spleen cells from day 61 L. donovani-infected B10.129(10M) donor mice into 550 rad syngeneic recipients, the pretreatment of mice with sublethal irradiation did not, as in the earlier studies of Scl-controlled L. major nonhealing or H-2-controlled L. donovani noncure phenotypes, have a clear or consistent prophylactic effect. Together with the progressive disease profile observed even for L. donovani at low parasite doses this suggests that, despite their ability to develop initial delayed-type hypersensitivity reactions to parasite antigen early in L. major infection, B10.129(10M) mice possess some inherent defect in ability to mount a cell-mediated response effective at the level of macrophage antileishmanial activity in vivo even when suppressor T cells are not generated. Further elucidation of this characteristically different noncuring/nonhealing phenotype may provide important insight into common events involved in the development of the cell-mediated immune response to both visceral and subcutaneous forms of leishmaniasis.


Assuntos
Antígenos de Histocompatibilidade/genética , Leishmaniose Visceral/genética , Leishmaniose/genética , Animais , Feminino , Ligação Genética , Hipersensibilidade Tardia , Imunização Passiva , Leishmaniose/imunologia , Leishmaniose/parasitologia , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/parasitologia , Masculino , Camundongos , Camundongos Endogâmicos , Quimera por Radiação
19.
Immunology ; 53(2): 345-55, 1984 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6490087

RESUMO

Acridine orange and ethidium bromide and a combination of fluorescent and transmitted light microscopy used in conjunction with the qualitative nitroblue tetrazolium assay for superoxide anion (O2-) release demonstrated dramatic differences in the binding of and respiratory burst (RB) activity elicited by promastigotes and amastigotes of Leishmania donovani in resident peritoneal macrophages (M phi) from C57BL/10ScSn mice. When amastigotes were incubated with M phi for 30 min the number of parasites per 100 M phi was 2-4-fold higher, a higher proportion of M phi became infected and the mean number of parasites per infected M phi was higher than in promastigote infections. RB activity was higher for promastigotes than amastigotes both in terms of the percentage of infected M phi containing formazan positive parasites and the percentage of individual formazan positive parasites. In an attempt to explain the differential response to promastigotes and amastigotes, RB activity was examined for sodium azide-treated, glutaraldehyde-fixed and heat-killed parasites and for various transformation intermediates between amastigotes and promastigotes. Binding and RB activity were also examined in conjunction with competitive binding assays designed to determine the specific receptors involved in ligand binding of both forms of the parasite to the M phi. The results indicate that, while amastigotes may possess an azide-sensitive mechanism which either competes for O2- produced or causes localized inactivation of RB activity, this cannot account for the full magnitude of the difference between the two forms of the parasite. The transformation and competitive binding studies suggest that the more likely explanation lies in both qualitative and quantitative differences in the distribution of surface ligands involved in binding the parasite to the M phi plasma membrane and that the well characterized mannose/fucose receptor may be important in promastigote, but not amastigote, binding and RB activity.


Assuntos
Leishmania/fisiologia , Macrófagos/parasitologia , Oxigênio/metabolismo , Animais , Líquido Ascítico , Azidas/farmacologia , Ligação Competitiva , Feminino , Leishmania/crescimento & desenvolvimento , Ativação de Macrófagos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Monossacarídeos/metabolismo , Azida Sódica
20.
Clin Exp Pharmacol Physiol ; 9(1): 69-75, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-7094435

RESUMO

1. Morphine pretreatment (8.0 mg/kg s.c.) induced no overt tolerance to its antinociceptive effect in mice 4 h later, but enhanced by the antagonistic potency of naloxone. 2. Pretreatment with chlorpromazine hydrochloride (0.5 2.0 mg/kg s.c.) potentiated the antinociceptive effect of morphine measured 4.5 h later. The antagonistic effect of naloxone was also enhanced. 3. The observed effect of chlorpromazine on naloxone potency was augmented when naloxone hydrochloride 0.2 mg/kg was administered in the pretreatment regime. 4. The enhanced naloxone potency induced by morphine pretreatment was inhibited by chlorpromazine administered 0.5 hr before the morphine pretreatment. 5. These results indicate that pretreatment with either morphine or chlorpromazine increased the antagonistic potency of naloxone. However, it appears that these two drugs act by different mechanisms.


Assuntos
Clorpromazina/farmacologia , Naloxona/farmacologia , Analgésicos , Animais , Relação Dose-Resposta a Droga , Interações Medicamentosas , Masculino , Camundongos , Morfina/farmacologia
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