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1.
Oecologia ; 202(1): 15-28, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37171625

RESUMO

Imaging spectroscopy has the potential to map closely related plant taxa at landscape scales. Although spectral investigations at the leaf and canopy levels have revealed relationships between phylogeny and reflectance, understanding how spectra differ across, and are inherited from, genotypes of a single species has received less attention. We used a common-garden population of four varieties of the keystone canopy tree, Metrosideros polymorpha, from Hawaii Island and four F1-hybrid genotypes derived from controlled crosses to determine if reflectance spectra discriminate sympatric, conspecific varieties of this species and their hybrids. With a single exception, pairwise comparisons of leaf reflectance patterns successfully distinguished varieties of M. polymorpha on Hawaii Island as well as populations of the same variety from different islands. Further, spectral variability within a single variety from Hawaii Island and the older island of Oahu was greater than that observed among the four varieties on Hawaii Island. F1 hybrids most frequently displayed leaf spectral patterns intermediate to those of their parent taxa. Spectral reflectance patterns distinguished each of two of the hybrid genotypes from one of their parent varieties, indicating that classifying hybrids may be possible, particularly if sample sizes are increased. This work quantifies a baseline in spectral variability for an endemic Hawaiian tree species and advances the use of imaging spectroscopy in biodiversity studies at the genetic level.


Assuntos
Variação Genética , Árvores , Havaí , Filogenia , Análise Espectral
2.
Acta Endocrinol (Buchar) ; 18(4): 488-493, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37152869

RESUMO

Introduction: Vitamin D is involved in differentiation and induction of erythropoiesis in bone marrow cells. Aim: We compared the serum 25(OH) vitamin D level in obese children versus control and found correlations between vitamin D level and hematological indices in obese children. Materials and methods: 25 overweight and obese patients and 15 normal weight children were enrolled in an observational study . Results: In obese children, the serum level of 25(OH) vitamin D was significantly (p<0.04) lower (20.60 ng/mL) compared with the value from normal weight ones (25.63 ng/mL) and the body fat percentage BFP was higher. We found a positive correlation (r=0.44, p<0.05) between serum vitamin D and hemoglobin level and a negative one between serum vitamin D and the number of platelets (r= -0.43, p<0.05). Also, the serum iron was at the lower normal limit in the obese children and negatively correlated with the percent of the body fat (r= -0,62, p<0.05). Conclusion: Obese children have vitamin D deficiency. The hemoglobin level and the number of platelets are correlated with the serum level of 25(OH) vitamin D. Supplements with vitamin D may have pleiotropic effects, including those on bone marrow activity.

3.
Oecologia ; 186(3): 765-782, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29302802

RESUMO

Trade-offs among plant functional traits indicate diversity in plant strategies of growth and survival. The leaf economics spectrum (LES) reflects a trade-off between short-term carbon gain and long-term leaf persistence. A related trade-off, between foliar growth and anti-herbivore defense, occurs among plants growing in contrasting resource regimes, but it is unclear whether this trade-off is maintained within plant communities, where resource gradients are minimized. The LES and the growth-defense trade-off involve related traits, but the extent to which these trade-off dimensions are correlated is poorly understood. We assessed the relationship between leaf economic and anti-herbivore defense traits among sunlit foliage of 345 canopy trees in 83 species on Barro Colorado Island, Panama. We quantified ten traits related to resource allocation and defense, and identified patterns of trait co-variation using multivariate ordination. We tested whether traits and ordination axes were correlated with patterns of phylogenetic relatedness, juvenile demographic trade-offs, or topo-edaphic variation. Two independent axes described ~ 60% of the variation among canopy trees. Axis 1 revealed a trade-off between leaf nutritional and structural investment, consistent with the LES. Physical defense traits were largely oriented along this axis. Axis 2 revealed a trade-off between investments in phenolic defenses versus other foliar defenses, which we term the leaf defense spectrum. Phylogenetic relationships and topo-edaphic variation largely did not explain trait co-variation. Our results suggest that some trade-offs among the growth and defense traits of outer-canopy trees may be captured by the LES, while others may occur along additional resource allocation dimensions.


Assuntos
Herbivoria , Folhas de Planta , Colorado , Panamá , Filogenia
4.
Ecol Appl ; 24(1): 84-93, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24640536

RESUMO

Information on landscape-scale patterns in species distributions and community types is vital for ecological science and effective conservation assessment and planning. However, detailed maps of plant community structure at landscape scales seldom exist due to the inability of field-based inventories to map a sufficient number of individuals over large areas. The Carnegie Airborne Observatory (CAO) collected hyperspectral and lidar data over Kruger National Park, South Africa, and these data were used to remotely identify > 500 000 tree and shrub crowns over a 144-km2 landscape using stacked support vector machines. Maps of community compositional variation were produced by ordination and clustering, and the importance of hillslope-scale topo-edaphic variation in shaping community structure was evaluated with redundancy analysis. This remote species identification approach revealed spatially complex patterns in woody plant communities throughout the landscape that could not be directly observed using field-based methods alone. We estimated that topo-edaphic variables representing catenal sequences explained 21% of species compositional variation, while we also uncovered important community patterns that were unrelated to catenas, indicating a large role for other soil-related factors in shaping the savanna community. Our results demonstrate the ability of airborne species identification techniques to map biodiversity for the evaluation of ecological controls on community composition over large landscapes.


Assuntos
Biodiversidade , Plantas/classificação , Demografia , África do Sul
5.
mBio ; 14(5): e0212323, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37800917

RESUMO

IMPORTANCE: Cryptococcosis studies often utilize the common C57BL/6J mouse model. Unfortunately, infection in these mice fails to replicate the basic course of human disease, particularly hampering immunological studies. This work demonstrates that SJL/J mice can recapitulate human infection better than other mouse strains. The immunological response to Cryptococcus infection in SJL/J mice was markedly different from C57BL/6J and much more productive in combating this infection. Characterization of infected mice demonstrated strain-specific genetic linkage and differential regulation of multiple important immune-relevant genes in response to Cryptococcus infection. While our results validate many of the previously identified immunological features of cryptococcosis, we also demonstrate limitations from previous mouse models as they may be less translatable to human disease. We concluded that SJL/J mice more faithfully recapitulate human cryptococcosis serving as an exciting new animal model for immunological and genetic studies.


Assuntos
Criptococose , Cryptococcus neoformans , Humanos , Camundongos , Animais , Cryptococcus neoformans/genética , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças
6.
Br J Cancer ; 107(12): 1917-24, 2012 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-23169286

RESUMO

BACKGROUND: Round 1 data of human papillomavirus (HPV) FOCAL, a three-arm, randomised trial, which aims to establish the efficacy of HPV DNA testing as a primary screen for cervical cancer, are presented. METHODS: The three arms are: Control arm - liquid based cytology with atypical squamous cells of unknown significance (ASC-US) triage with hrHPV testing; Intervention Arm - hrHPV at entry with liquid-based cytology (LBC) triage of hrHPV positives, with exit screen at 4 years; Safety check arm - hrHPV at entry with LBC triage of hrHPV positives with exit screen at 2 years. RESULTS: A total of 6154 women were randomised to the control arm and 12 494 to the HPV arms (intervention and safety check). In the HPV arm, the baseline cervical intraepithelial neoplasia (CIN)2+ and CIN3+ rate was 9.2/1000 (95%CI; 7.4, 10.9) and 4.8/1000 (95%CI; 3.6, 6.1), which increased to 16.1/1000 (95%CI 13.2, 18.9) for CIN2+ and to 8.0/1000 (95%CI; 5.9, 10.0) for CIN3+ after subsequent screening of HPV-DNA-positive/cytology-negative women. Detection rate in the control arm remained unchanged after subsequent screening of ASC-US-positive/hrHPV DNA-negative women at 11.0/1000 for CIN2+ and 5.0/1000 for CIN3+. CONCLUSION: After subsequent screening of women who were either hrHPV positive/cytology negative or ASC-US positive/HPV negative, women randomised to the HPV arms had increased CIN2+ detection compared with women randomised to the cytology arm.


Assuntos
Alphapapillomavirus/isolamento & purificação , Técnicas Citológicas/métodos , Detecção Precoce de Câncer/métodos , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/virologia , Adulto , Algoritmos , Alphapapillomavirus/genética , Canadá/epidemiologia , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/virologia , Colposcopia , DNA Viral/isolamento & purificação , Feminino , Humanos , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Infecções por Papillomavirus/epidemiologia , Parceiros Sexuais , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/prevenção & controle , Esfregaço Vaginal , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/virologia
7.
Bioorg Med Chem Lett ; 21(4): 1134-40, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-21269824

RESUMO

Structure-guided lead optimization of recently described benzimidazolyl acetamides addressed the key liabilities of the previous lead compound 1. These efforts culminated in the discovery of 4-{(S)-2-[2-(4-chloro-phenyl)-5,6-difluoro-benzoimidazol-1-yl]-2-cyclohexyl-acetylamino}-3-fluoro-benzoic acid 7g, a highly potent and selective FXR agonist with excellent physicochemical and ADME properties and potent lipid lowering activity after oral administration to LDL receptor deficient mice.


Assuntos
Benzimidazóis/química , Receptores Citoplasmáticos e Nucleares/agonistas , para-Aminobenzoatos , Ácido 4-Aminobenzoico/síntese química , Ácido 4-Aminobenzoico/química , Ácido 4-Aminobenzoico/farmacocinética , Administração Oral , Animais , Benzimidazóis/síntese química , Benzimidazóis/farmacocinética , Sítios de Ligação , Simulação por Computador , Cristalografia por Raios X , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microssomos Hepáticos/metabolismo , Conformação Molecular , Ratos , Ratos Wistar , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores de LDL/deficiência , Receptores de LDL/genética , Receptores de LDL/metabolismo , Relação Estrutura-Atividade
8.
Curr Microbiol ; 62(6): 1671-6, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21394509

RESUMO

Two formulations of acrylic varnish, with and without either of two dry film biocides--one a mixture of isothiazolinones and benzimidazole derivatives, and the other a carbamate--were tested in vitro for their activity against mixtures of filamentous fungi and cyanobacteria found on sandstone buildings. Growth on filter-paper squares coated with the varnishes was assessed semi-quantitatively by naked eye, quantitatively by image analysis and chemically by measurement of ergosterol and chlorophyll a. The lower solvent content (higher resin) varnish was more inhibitory to cyanobacteria than the higher varnish content, whilst the opposite was true for the fungal inoculum. The carbamate biocide was effective against cyanobacteria, unlike the isothiazolinone mixture, but the latter produced more inhibition of fungal growth. The three assay methods produced generally similar results, although visual observation was obviously the most imprecise. There was an anomaly in the ergosterol measurements, which was considered to be caused by the varying ergosterol content and unequal inhibition of the three fungal genera used in the inoculum. Fusarium sp. was shown to contain higher levels of this membrane component than Cladosporium sp. and Penicillium sp. For this reason, the most appropriate method overall, giving reliable quantitative results, was deemed to be the image analysis.


Assuntos
Materiais de Construção/microbiologia , Cianobactérias/efeitos dos fármacos , Desinfetantes/farmacologia , Fungos/efeitos dos fármacos , Testes de Sensibilidade Microbiana/métodos , Pintura/análise , Química Farmacêutica , Cianobactérias/crescimento & desenvolvimento , Desinfetantes/química , Fungos/crescimento & desenvolvimento
9.
Neuroscience ; 153(4): 1300-8, 2008 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-18455883

RESUMO

Although the posterior oral cavity and oropharynx play a major role in swallowing, their central representation is poorly understood. High-field functional magnetic resonance imaging of the brain was used to study the central processing of brief air-pulses, delivered to the peritonsillar region of the lateral oropharynx, in six healthy adults. Bilateral air-pulse stimulation was associated with the activation of a bilateral network including the primary somatosensory cortex and the thalamus, classic motor areas (primary motor cortex, supplementary motor area, cingulate motor areas), and polymodal areas (including the insula and frontal cortex). These results suggest that oropharyngeal stimulation can activate a bilaterally distributed cortical network that overlaps cortical regions previously implicated in oral and pharyngeal sensorimotor functions such as tongue movement, mastication, and swallowing. The present study also demonstrates the utility of air-pulse stimulation in investigating oropharyngeal sensorimotor processing in functional brain imaging experiments.


Assuntos
Mapeamento Encefálico , Encéfalo/irrigação sanguínea , Imageamento por Ressonância Magnética , Orofaringe/inervação , Adulto , Feminino , Lateralidade Funcional , Humanos , Processamento de Imagem Assistida por Computador/métodos , Oxigênio/sangue , Estimulação Física/métodos
10.
Biomed Res Int ; 2018: 3904139, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29682540

RESUMO

OBJECTIVES: (1) To determine whether manual (MTB), or electric, tooth brushing (ETB) modulates whole salivary flow rate in older adults who are free of systemic disease. (2) To determine the duration of the brushing-related modulation of salivary flow rate. (3) To compare salivary flow rate modulation associated with MTB and ETB. METHOD: Twenty-one adults aged 60 years and older participated in two experimental sessions during which they used a manual, or electric, toothbrush to brush their teeth, tongue, and palate. Whole salivary flow rates were determined using the draining method before, during, and after brushing. Differences in salivary flow rates across time periods, and between conditions, were examined using paired samples t-tests applying a Holm-Bonferroni sequential procedure (pcorr < 0.0045). The relationship between tooth brushing and age with respect to maximum salivary flow rate increase was examined using Pearson's correlation coefficient (p < 0.05). RESULTS/CONCLUSION: Whole salivary flow rates increased during, and for up to 5 minutes following, tooth brushing in adults aged 60 years and older who were free of systemic disease. The salivary effects of MTB and ETB were not significantly different. A moderate, positive correlation was observed between tooth-brushing-related maximum salivary flow rate increase and age.


Assuntos
Saliva/fisiologia , Idoso , Idoso de 80 Anos ou mais , Placa Dentária/fisiopatologia , Índice de Placa Dentária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Palato/fisiologia , Língua/fisiologia , Dente/fisiologia , Escovação Dentária/métodos
11.
JDR Clin Trans Res ; 2(4): 330-342, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30931751

RESUMO

While the oral health of persons with dementia has been shown to be poor, no systematic reviews have been published that examined the topic in depth, including participants with dementia representing the full spectrum of disease severity, and evaluating a broad scope of oral health assessments. The aim of this study was to conduct a current literature review to fill this gap in knowledge. A systematic search of 5 databases (CINAHL, PubMed, EMBASE, Scopus, and ISI Web of Science) was conducted to identify all relevant studies published up to May 2016. There were no exclusions related to study type, severity of dementia, dentate status, or living arrangements. Results were reported descriptively and summarized. Meta-analyses were performed where possible and reported as mean difference (MD) or standardized mean difference (SMD), with a 95% confidence interval (CI). Twenty-eight studies were identified. Assessments were conducted of tooth status, active dental caries, hygiene (plaque/calculus) of natural and artificial teeth, periodontal diseases, denture status (retention, stability, denture-related mucosal lesions), and oral health-related quality of life. Across all evaluations, persons with dementia generally had scores/results suggestive of poor oral health. In meta-analyses, compared with persons without dementia, those with dementia had a significantly fewer number of teeth (MD, -1.52; 95% CI, -0.2.52 to -0.52; P = 0.003; n = 13 studies), more carious teeth (SMD, 0.29; 95% CI, 0.03 to 0.48; P = 0.028; n = 9), significantly worse oral hygiene evaluated using a broad range of assessment tools (SMD, 0.88; 95% CI, 0.57 to 1.19, P < 0.0001; n = 7), and significantly poorer periodontal health (SMD, 0.38; 95% CI, 0.06 to 0.70; P = 0.02; n = 6 studies). The oral health status of persons with mild to severe forms of dementia, who were living in both the community and residential care facilities, was found to be poor across a broad range of dental assessments. Knowledge Transfer Statement: The results of this study define the scope of oral issues and quantify the degree of impairment in individuals with dementia, evaluated using a variety of oral health measures. The results revealed that poor oral health is associated with dementia.

12.
Science ; 355(6323): 385-389, 2017 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-28126815

RESUMO

Functional biogeography may bridge a gap between field-based biodiversity information and satellite-based Earth system studies, thereby supporting conservation plans to protect more species and their contributions to ecosystem functioning. We used airborne laser-guided imaging spectroscopy with environmental modeling to derive large-scale, multivariate forest canopy functional trait maps of the Peruvian Andes-to-Amazon biodiversity hotspot. Seven mapped canopy traits revealed functional variation in a geospatial pattern explained by geology, topography, hydrology, and climate. Clustering of canopy traits yielded a map of forest beta functional diversity for land-use analysis. Up to 53% of each mapped, functionally distinct forest presents an opportunity for new conservation action. Mapping functional diversity advances our understanding of the biosphere to conserve more biodiversity in the face of land use and climate change.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Florestas , Clima , Geologia , Hidrologia , Lasers , Peru , Análise Espectral/métodos
13.
Curr Top Microbiol Immunol ; 295: 325-56, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16265897

RESUMO

Membrane transport proteins are integral membrane proteins that mediate the passage across the membrane bilayer of specific molecules and/or ions. Such proteins serve a diverse range of physiological roles, mediating the uptake of nutrients into cells, the removal of metabolic wastes and xenobiotics (including drugs), and the generation and maintenance of transmembrane electrochemical gradients. In this chapter we review the present state of knowledge of the membrane transport mechanisms underlying the cell physiology of the intraerythrocytic malaria parasite and its host cell, considering in particular physiological measurements on the parasite and parasitized erythrocyte, the annotation of transport proteins in the Plasmodium genome, and molecular methods used to analyze transport protein function.


Assuntos
Eritrócitos/parasitologia , Proteínas de Membrana Transportadoras/metabolismo , Plasmodium/metabolismo , Proteínas de Protozoários/metabolismo , Animais , Transporte Biológico/genética , Membrana Celular/fisiologia , Permeabilidade da Membrana Celular , Membrana Eritrocítica/fisiologia , Genes de Protozoários , Membranas Intracelulares/fisiologia , Proteínas de Membrana Transportadoras/química , Proteínas de Membrana Transportadoras/genética , Permeabilidade , Plasmodium/química , Plasmodium/genética , Proteínas de Protozoários/química , Proteínas de Protozoários/genética
14.
J Food Prot ; 69(7): 1561-4, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16865886

RESUMO

Listeria monocytogenes can pose a serious threat in several areas of the nation's food supply including ready-to-eat seafood products. Use of irradiation processing can potentially reduce the risk of listeriosis caused by consumption of ready-to-eat seafood products. This study measured the effect of X-ray irradiation on reducing the population of L. monocytogenes on ready-to-eat, vacuum-packaged smoked mullet. Smoked mullet were inoculated with a five-strain mixture of L. monocytogenes (10(4) CFU/g), vacuum packaged, and irradiated (0, 0.5, 1.0, 1.5, and 2.0 kGy). The packaged fish were then stored at 3 and 10 degrees C for 90 and 17 days, respectively. Radiation doses of 0.5, 1.0, and 1.5 kGy reduced the initial population of L. monocytogenes by 1.1, 1.6, and 2.1 log CFU/g, respectively. The 2.0-kGy dose reduced L. monocytogenes to undetectable levels with no recovery growth at either temperature. Compared to the control, irradiation at 1.5 kGy demonstrated 1.0 and 1.7 log CFU/g less growth at 3 degrees C after 60 days and 10 degrees C after 17 days, respectively. Sensory flavor analysis was conducted to determine if a difference existed between irradiated samples. Panelists indicated that there were no differences among treated and untreated samples. An X-ray dose of 2 kGy effectively eliminated 10(4) CFU/g L. monocytogenes on smoked mullet without changing sensory quality.


Assuntos
Irradiação de Alimentos/métodos , Embalagem de Alimentos/métodos , Conservação de Alimentos/métodos , Listeria monocytogenes/efeitos da radiação , Listeriose/epidemiologia , Alimentos Marinhos , Animais , Contagem de Colônia Microbiana , Qualidade de Produtos para o Consumidor , Relação Dose-Resposta à Radiação , Manipulação de Alimentos/métodos , Microbiologia de Alimentos , Humanos , Fatores de Risco , Alimentos Marinhos/microbiologia , Alimentos Marinhos/normas , Smegmamorpha , Paladar , Temperatura , Fatores de Tempo , Vácuo , Raios X
15.
Diabetes Care ; 17(4): 316-7, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8026288

RESUMO

OBJECTIVE: To determine whether didanosine (DDI), one of the drugs commonly used to treat infection with human immunodeficiency virus (HIV), contributes to the development of diabetes and hyperosmolar nonketotic diabetic syndrome (HNKDS). CASE SUMMARY: One female patient was treated with DDI for infection with HIV during pregnancy. Soon after starting DDI treatment, she developed diabetes, which progressed to HNKDS. CONCLUSIONS: Although not reported in the literature, hyperglycemia following treatment with DDI has been noted in 82 patients and is usually associated with pancreatitis. DDI should be recognized as one of the drugs known to potentially cause diabetes and HNKDS. With the increasing use of DDI and other drugs that cause hyperglycemia, such as pentamidine and dapsone, blood glucose should be monitored frequently in the HIV-infected patients.


Assuntos
Didanosina/efeitos adversos , Infecções por HIV/tratamento farmacológico , Soropositividade para HIV/tratamento farmacológico , Hiperglicemia/induzido quimicamente , Coma Hiperglicêmico Hiperosmolar não Cetótico/induzido quimicamente , Complicações Infecciosas na Gravidez/tratamento farmacológico , Gravidez em Diabéticas/induzido quimicamente , Adulto , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Didanosina/uso terapêutico , Feminino , Humanos , Monitorização Fisiológica , Gravidez , Zidovudina/uso terapêutico
16.
J Bone Miner Res ; 6(10): 1137-42, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1665677

RESUMO

Synthetic analogs of chicken and human CGRP were used to define structure-function relationships in a murine osteoblast precursor cell line, KS-4, that exhibits a substantial cyclic AMP response to CGRP but no response to calcitonin. Human CGRP had 40% of the activity of chicken CGRP, but [Asp-14]-human CGRP was equipotent with chicken CGRP. Similar observations were made previously for calcium- and phosphate-lowering effects. Des-1-Ala,deamino CGRP compounds of both human and chicken origin were three-fold more potent than the respective native CGRPs. The [4-F-Phe)-37]-chicken CGRP analog had a four-fold enhanced activity. In all of the 13 analogs either truncated amino-terminally or missing the (2-7)-disulfide bridge, biologic activity was greatly reduced (0.1% of chicken CGRP), as it was in chicken CGRP-(1-36)-OH, which lacks the C-terminal amino acid. The same analog has been shown to retain a hypocalcemic effect, which is most likely mediated through calcitonin receptors. In confirmation of their antagonistic effect reported in liver, analogs that lack the N-terminal ring structure exhibited significant antagonistic activity. The data illustrate the specificity of CGRP receptors in promoting cyclic AMP formation in osteoblast-like cells. Such CGRP analogs will be useful in investigating structure-function relationships of CGRP.


Assuntos
Peptídeo Relacionado com Gene de Calcitonina/farmacologia , AMP Cíclico/metabolismo , Osteoblastos/efeitos dos fármacos , Animais , Peptídeo Relacionado com Gene de Calcitonina/análogos & derivados , Peptídeo Relacionado com Gene de Calcitonina/química , Peptídeo Relacionado com Gene de Calcitonina/genética , Cálcio/metabolismo , Linhagem Celular , Galinhas , Humanos , Osteoblastos/metabolismo , Fosfatos/metabolismo , Relação Estrutura-Atividade
17.
Am J Clin Nutr ; 32(8): 1659-69, 1979 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-463803

RESUMO

For 6 weeks, 10 men and nine women aged 35 to 55 consumed each of two diets in a cross-over design. The diets were comprised of identical natural foods with 30% of the calories as either sucrose or cooked wheat starch. Carbohydrate, fat and protein supplied 43, 42, and 15% of the calories, respectively. Of the calories 10% were eaten at breakfast (7:00 to 8:30 AM) and 90% at dinner (4:30 to 6:30 PM). Initial body weights were essentially maintained. Total serum lipids, triglycerides, and total cholesterol levels were significantly higher when the subjects consumed the sucrose diet than when they consumed the starch diet. Increases associated with the sucrose diet were greatest for triglycerides (33.0%). In a subgroup of nine subjects with triglyceride levels above the normal range, sucrose feeding increased triglyceride levels 45.2%. Triglycerides and pre-beta lipoproteins were significantly higher in males than in females. Pre-beta lipoproteins were 32% higher when the subjects consumed sucrose than when they consumed starch. For alpha and beta lipoproteins, small, nonsignificant increases were associated with sucrose feeding. Serum free fatty acids were not affected by diet. These results indicate that the consumption of sucrose can increase blood lipids that are considered to be risk factors in heart disease and that males and carbohydrate-sensitive individuals may be more susceptible than others to the effects of sucrose.


Assuntos
Carboidratos da Dieta , Jejum , Lipídeos/sangue , Amido , Sacarose , Adulto , Peso Corporal , Colesterol/sangue , Ingestão de Energia , Ácidos Graxos não Esterificados/sangue , Feminino , Humanos , Lipoproteínas/sangue , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Triglicerídeos/sangue
18.
Mol Vis ; 5: 36, 1999 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-10617773

RESUMO

PURPOSE: Lysophosphatidic acid induces neurite retraction; it is also present in tears and aqueous humor. We determined whether lysophosphatidic acid induces HSV-1 reactivation in latently infected rabbits and whether the nerve growth associated protein GAP-43 undergoes posttranslational modification during the course of HSV-1 infection. METHODS: Rabbits were infected with HSV-1 and acute infection was documented by slit lamp examination. Corneas of latently infected rabbits were treated with lysophosphatidic acid or lysophosphatidylserine (structurally similar but lacking biological potency). For application to the cornea, these compounds were impregnated into collagen shields, applied as topical drops, or iontophoresed. In another experiment, corneas of latently infected rabbits were either untreated or treated iontophoretically with lysophosphatidic acid, lysophosphatidylserine, or saline. Ocular swabs detected shedding of infectious virus. Western blot and immunoprecipitation identified GAP-43 in corneal extracts and densitometry of silver-stained isoelectric focusing gels measured changes in GAP-43 isoform abundance. RESULTS: Iontophoresis of lysophosphatidic acid induced HSV-1 shedding more frequently than lysophosphatidylserine or saline. Viral shedding induced by collagen shield and topical drop administration was low and not significantly different for lysophosphatidic acid and lysophosphatidylserine. Five discrete GAP-43 isoforms predominated in the IEF gels. Most abundant were the pI 4.7 band in uninfected cornea and the pI 5.05 band in latently-infected cornea. Compared to latently-infected cornea, there was no significant change in isoform abundance 1 h after lysophosphatidic acid iontophoresis, but 24 and 72 h later, the pI 5. 05 band was diminished. CONCLUSIONS: Lysophosphatidic acid can induce HSV-1 reactivation and changes in GAP-43 pI suggest that posttranslational modifications, possibly related to phosphorylation and ADP-ribosylation, are occurring during HSV-1 latency and after LPA is iontophoretically applied to the cornea. How lysophosphatidic acid-induced signaling, HSV-1 reactivation, and GAP-43 pI are related remains to be determined.


Assuntos
Proteína GAP-43/metabolismo , Herpesvirus Humano 1/crescimento & desenvolvimento , Lisofosfolipídeos/administração & dosagem , Ativação Viral/efeitos dos fármacos , Animais , Herpesvirus Humano 1/efeitos dos fármacos , Iontoforese , Ponto Isoelétrico , Ceratite Herpética/metabolismo , Ceratite Herpética/virologia , Lisofosfolipídeos/farmacologia , Isoformas de Proteínas , Processamento de Proteína Pós-Traducional , Coelhos , Fatores de Tempo , Eliminação de Partículas Virais/efeitos dos fármacos
19.
Int J Parasitol ; 19(6): 585-96, 1989 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2807715

RESUMO

Muscle, hypodermis and gastrointestinal epithelial cells from adult female Ascaris lumbricoides var. suum were found to contain serotonin based upon glyoxylic acid induced histofluorescence and indirect immunolabeling with an antiserotonin monoclonal antibody conjugated to protein A-colloidal gold. Histofluorescence indicated that muscle-hypodermis and intestinal epithelial cells contained significant concentrations of 5-hydroxytryptamine while fluorescence was absent in the nerve cord and cuticle. Immunolabeling at the ultrastructural level indicated that serotonin was sequestered in electron-opaque patches, dense vesicles and mitochondria of the muscle-hypodermis and intestinal tissue. Perfusion of whole worms and isolated tissues with 10(4) M-serotonin further indicated: (1) immunolabeled patches and dense vesicles were often associated with cytoskeletal elements, (2) serotonin did not appear to enter the intestinal or muscle cells by endocytosis, (3) immunolabeled patches examined with energy dispersive X-ray spectrometry (X-ray microanalysis) were found to contain iron at concentrations approximately double that of the surrounding cytoplasm.


Assuntos
Ascaris/análise , Serotonina/análise , Animais , Microanálise por Sonda Eletrônica , Feminino , Histocitoquímica , Imuno-Histoquímica , Microscopia Eletrônica de Varredura
20.
Novartis Found Symp ; 226: 55-66; discussion 66-73, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10645538

RESUMO

The malaria-infected erythrocyte shows an increased permeability to a wide range of solutes. The increase is mediated in part by parasite-induced new permeation pathways (NPP) and in part (for some solutes, under some conditions) by increased activity of endogenous transporters. The NPP provide the major route for the influx into the infected cell of a number of essential nutrients, but although the functional characteristics of these pathways are understood in some detail, they are yet to be identified at a molecular level. Lucifer yellow, a fluorescent anion, is taken up by malaria-infected erythrocytes to a much greater extent than uninfected erythrocytes via a pathway that differs in its pharmacological characteristics from the NPP. The nature, origin and location of this pathway remain to be established.


Assuntos
Eritrócitos/parasitologia , Interações Hospedeiro-Parasita , Plasmodium , Animais , Transporte Biológico Ativo
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