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BACKGROUND: Family-based strategies to reduce the risk of overweight in childhood are needed in the Caribbean. AIM: To investigate the associations between parental characteristics and risk of overweight and explore possible mechanisms. METHODS: Data from a parenting intervention were analysed. Parental characteristics were obtained by questionnaire at enrolment. At 18 months, 501 infants (82.9% of cohort) had weight and length measured using standardized methods. The association of parents' characteristics with risk of infant overweight was assessed using random-effects logistic regression. Four focus groups among mothers in Jamaica were conducted to explore mechanisms. RESULTS: Overall, 20.6% of infants were 'at risk of overweight'. Fathers were present in 52% of households. Fathers' presence [OR (95% CI) 0.60 (0.37-0.96)] was associated with reduced risk of overweight independent of socioeconomic status. Mothers reported that fathers encouraged healthier practices. CONCLUSION: Fathers may be important agents of change in intervention strategies to prevent childhood overweight.
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Glycosylphosphatidylinositol (GPI) anchors and glycoinositolphospholipids (GIPLs) from parasitic protozoa have been shown to exert a wide variety of effects on cells of the host innate immune system. However, the receptor(s) that are triggered by these protozoan glycolipids has not been identified. Here we present evidence that Trypanosoma cruzi-derived GPI anchors and GIPLs trigger CD25 expression on Chinese hamster ovary-K1 cells transfected with CD14 and Toll-like receptor-2 (TLR-2), but not wild-type (TLR-2-deficient) Chinese hamster ovary cells. The protozoan-derived GPI anchors and GIPLs containing alkylacylglycerol and saturated fatty acid chains or ceramide were found to be active in a concentration range of 100 nM to 1 microM. More importantly, the GPI anchors purified from T. cruzi trypomastigotes, which contain a longer glycan core and unsaturated fatty acids in the sn-2 position of the alkylacylglycerolipid component, triggered TLR-2 at subnanomolar concentrations. We performed experiments with macrophages from TLR-2 knockout and TLR-4 knockout mice, and found that TLR-2 expression appears to be essential for induction of IL-12, TNF-alpha, and NO by GPI anchors derived from T. cruzi trypomastigotes. Thus, highly purified GPI anchors from T. cruzi parasites are potent activators of TLR-2 from both mouse and human origin. The activation of TLR-2 may initiate host innate defense mechanisms and inflammatory response during protozoan infection, and may provide new strategies for immune intervention during protozoan infections.
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Proteínas de Drosophila , Glicosilfosfatidilinositóis/fisiologia , Glicoproteínas de Membrana/metabolismo , Receptores de Superfície Celular/metabolismo , Trypanosoma cruzi/imunologia , Animais , Células CHO , Linhagem Celular , Cricetinae , Relação Dose-Resposta Imunológica , Glicolipídeos/fisiologia , Glicosilfosfatidilinositóis/isolamento & purificação , Inflamação/imunologia , Inflamação/parasitologia , Macrófagos/imunologia , Macrófagos/metabolismo , Glicoproteínas de Membrana/deficiência , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/fisiologia , Camundongos , Camundongos Knockout , NF-kappa B/fisiologia , Fosfolipídeos/fisiologia , Receptores de Superfície Celular/deficiência , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/fisiologia , Receptores de Interleucina-2/biossíntese , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Receptor 2 Toll-Like , Receptor 4 Toll-Like , Receptores Toll-Like , Transfecção , Trypanosoma cruzi/química , Trypanosoma cruzi/crescimento & desenvolvimentoRESUMO
PURPOSE: Human T-cell lymphotrophic virus type 1 is a RNA retrovirus that primarily affects CD4+ T-cells. Human T-cell lymphotrophic virus type 1 infection is the established cause of adult T-cell leukemia/lymphoma, an aggressive malignancy of CD4+ T-cells, and two nonneoplastic conditions: human T-cell lymphotrophic virus type 1-associated myelopathy/tropical spastic paraparesis and human T-cell lymphotrophic virus type 1 uveitis. Other reported ophthalmic manifestations of human T-cell lymphotrophic virus type 1 infection include lymphomatous and leukemic infiltrates in the eye and ocular adnexa in patients with adult T-cell leukemia/lymphoma, retinal pigmentary degeneration, and neuro-ophthalmic disorders in patients with human T-cell lymphotrophic virus type 1-associated myelopathy/tropical spastic paraparesis and keratoconjunctivitis sicca, episcleritis, and sclerouveitis in asymptomatic human T-cell lymphotrophic virus type 1 carriers. This report describes the ocular findings in three Jamaican patients with human T-cell lymphotrophic virus type 1 infection and adult T-cell leukemia/lymphoma. METHODS: The clinical records of three patients with human T-cell lymphotrophic virus type 1 infection and adult T-cell leukemia/lymphoma examined at the National Eye Institute were reviewed. Each patient had one or more complete ophthalmic evaluations. RESULTS: All three patients had corneal abnormalities, including corneal haze and central opacities with thinning; bilateral immunoprotein keratopathy; and peripheral corneal thinning, scarring, and neovascularization. All three patients had elevated serum immunoglobulin levels. CONCLUSIONS: We believe that the novel corneal findings in these patients are most likely a consequence of the hypergammaglobulinemia induced by the human T-cell lymphotrophic virus type 1 infection or the T-cell malignancy.
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Doenças da Córnea/virologia , Infecções Oculares Virais , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Paraparesia Espástica Tropical , Adulto , Doenças da Córnea/diagnóstico , Doenças da Córnea/etnologia , Infecções Oculares Virais/diagnóstico , Infecções Oculares Virais/etnologia , Infecções Oculares Virais/virologia , Feminino , Anticorpos Anti-HTLV-I/análise , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Humanos , Hipergamaglobulinemia/imunologia , Hipergamaglobulinemia/virologia , Imunoglobulina G/imunologia , Jamaica/epidemiologia , Masculino , Pessoa de Meia-Idade , Paraparesia Espástica Tropical/diagnóstico , Paraparesia Espástica Tropical/etnologia , Paraparesia Espástica Tropical/virologia , Acuidade VisualRESUMO
OBJECTIVES: We have reported colitis with ileal lymphoid nodular hyperplasia (LNH) in children with regressive autism. The aims of this study were to characterize this lesion and determine whether LNH is specific for autism. METHODS: Ileo-colonoscopy was performed in 21 consecutively evaluated children with autistic spectrum disorders and bowel symptoms. Blinded comparison was made with 8 children with histologically normal ileum and colon, 10 developmentally normal children with ileal LNH, 15 with Crohn's disease, and 14 with ulcerative colitis. Immunohistochemistry was performed for cell lineage and functional markers, and histochemistry was performed for glycosaminoglycans and basement membrane thickness. RESULTS: Histology demonstrated lymphocytic colitis in the autistic children, less severe than classical inflammatory bowel disease. However, basement membrane thickness and mucosal gamma delta cell density were significantly increased above those of all other groups including patients with inflammatory bowel disease. CD8(+) density and intraepithelial lymphocyte numbers were higher than those in the Crohn's disease, LNH, and normal control groups; and CD3 and plasma cell density and crypt proliferation were higher than those in normal and LNH control groups. Epithelial, but not lamina propria, glycosaminoglycans were disrupted. However, the epithelium was HLA-DR(-), suggesting a predominantly T(H)2 response. INTERPRETATION: Immunohistochemistry confirms a distinct lymphocytic colitis in autistic spectrum disorders in which the epithelium appears particularly affected. This is consistent with increasing evidence for gut epithelial dysfunction in autism.
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Transtorno Autístico/complicações , Doenças Inflamatórias Intestinais/imunologia , Doenças Linfáticas/imunologia , Linfócitos T/metabolismo , Adolescente , Transtorno Autístico/imunologia , Linfócitos T CD8-Positivos/metabolismo , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Doenças Linfáticas/complicações , Doenças Linfáticas/patologia , MasculinoRESUMO
Carotid percutaneous transluminal angioplasty, with or without stent implantation, is becoming another therapeutic option for carotid revascularization. To evaluate the feasibility and effectiveness of the technique, from October of 1995 to March of 1997, we performed 24 percutaneous transluminal angioplasty procedures in 22 patients with severe extracranial carotid artery stenosis. Three common carotid and 21 internal carotid arteries were treated, and 19 procedures included stent implantation using nonarticulated PALMAZ stents (P154 and P204). Twelve patients were asymptomatic and 10 patients were symptomatic; 2 of the symptomatic patients had complete obstruction of the internal carotid artery that was successfully recanalized. Technical and angiographic success was achieved in 23 of 24 procedures, with the carotid artery obstruction diminishing from 85.6% +/- 8.5% to 5.7% +/- 3.2% (P < 0.001). Average stenosis length was 12.5 +/- 3.1 mm, and mean time of carotid occlusion during balloon inflation was 11.5 +/- 2.5 seconds. Three patients experienced transitory seizures during the procedure prior to dilation, 1 patient had a minor stroke with complete recovery within 72 hours, and 1 patient had a major stroke and died 45 days after the procedure. Clinical follow-up was achieved in all patients (mean, 10.5 +/- 7.2 months) and angiographic follow-up in 16 patients (mean, 6.3 +/- 1.2 months). The results obtained in this initial experience provide adequate support to continue further evaluation of this new therapeutic strategy.
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Angioplastia com Balão/instrumentação , Isquemia Encefálica/terapia , Estenose das Carótidas/terapia , Stents , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/diagnóstico por imagem , Artéria Carótida Primitiva/diagnóstico por imagem , Artéria Carótida Interna/diagnóstico por imagem , Estenose das Carótidas/diagnóstico por imagem , Angiografia Cerebral , Desenho de Equipamento , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Ataque Isquêmico Transitório/diagnóstico por imagem , Ataque Isquêmico Transitório/terapia , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
Coeliac disease is uncommon in populations of non-European origin. Two English born West Indian children with coeliac disease are presented. The diagnosis should be considered in children of West Indian origin with chronic diarrhoea.
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Doença Celíaca/etnologia , Doença Celíaca/imunologia , Inglaterra , Feminino , Antígenos HLA-D/análise , Humanos , Lactente , Masculino , Índias Ocidentais/etnologiaRESUMO
Cow milk-sensitive enteropathy is a temporary disorder of infancy characterized by a variably abnormal small intestinal mucosa while milk is in the diet. This abnormality is reversed by a cow milk-free diet, only to recur on challenge. Important predisposing factors are age (< 3 years), transient IgA immunodeficiency, atopy, and early bottle feeding. The disorder is diagnosed histologically by evidence of mild-to-moderate partial villous atrophy with thin, often patchy mucosa. For an accurate clinical diagnosis, challenge with the offending food after a demonstrated response to cow milk elimination is critical. When available, serial small intestinal bowel biopsies related to elimination and challenge are also important. Treatment is elimination of cow milk and all foods based on cow milk, and substitution of cow milk feedings with commercially available formulas free of cow milk protein. Five types of cow milk substitutes are described; only nutritionally complete formulas are recommended. Later, a milk challenge will determine the timing of safe reintroduction of cow milk to the diet, at a time when the child is gaining weight, thriving, and symptom free. This dietary treatment is always temporary; reintroduction of a normal diet is nearly always possible between 1 and 2 years of age.
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Alimentos Infantis , Enteropatias/imunologia , Hipersensibilidade a Leite/imunologia , Proteínas do Leite/efeitos adversos , Causalidade , Pré-Escolar , Humanos , Lactente , Enteropatias/sangue , Enteropatias/diagnóstico , Enteropatias/dietoterapia , Hipersensibilidade a Leite/sangue , Hipersensibilidade a Leite/diagnóstico , Hipersensibilidade a Leite/dietoterapiaRESUMO
Behavioral economic analysis has shown food choice in normal weight adults is influenced by both liking and constraints on access to food. The present study assessed the contributions of food liking and environmental constraints to choice of moderately liked, low-calorie foods or highly liked high-calorie foods in obese children. Access to the moderately liked food remained on a VR2 schedule, while response requirements for the highly liked food ranged from VR2 to VR32. Subjects chose to work for the higher-rated food at comparisons up to VR2/VR4, showed no preference at VR2/VR8 and their choice shifted to the lower rated food when response requirements for the highly liked food were increased to VR16. These results show that both subjective and environmental factors contribute to children's choice of foods.
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Preferências Alimentares/psicologia , Obesidade/psicologia , Criança , Ingestão de Energia , Feminino , Humanos , Masculino , Fatores de TempoRESUMO
Although the SAC generally are healthy and tolerant of a wide variety of management schemes, a number of noninfectious diseases have been documented to occur, affecting all body systems. Gastrointestinal diseases appear to be the most common afflictions, particularly dental diseases, indigestion, ulceration of the third compartment, and the various causes of colic, such as enteritis, peritonitis, and intestinal accidents. Diseases of the urinary system (urolithiasis, amyloidosis, and glomerulonephritis in particular), the nervous system (especially various compressive lesions of the spinal cord), and the respiratory system (such as obstructive pulmonary diseases) are not uncommon. Diseases of the cardiovascular system (other than congenital defects), hemolymphatic system, and nonsurgical diseases of the musculoskeletal system only rarely are encountered. Heat stress appears to be a very common problem in certain areas, but other metabolic diseases (ketosis, hypocalcemia, and hypothyroidism) are of minor importance. It is assumed that SAC are susceptible to most of the same toxicities that affect domestic livestock species. The best documented examples appear to be the Ericaceae family of plants (laurels, rhododendrons, and so on) and the organophosphate chlorpyrifos. Neoplasia occasionally is seen; examples include lymphosarcoma, gastric squamous cell carcinoma, and adenocarcinoma. As the longevity of these species increases because of their pet status, neoplasia can be expected to become more common. The treatment of most of these conditions is based upon extrapolation from domestic ruminants.
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Artiodáctilos , Camelídeos Americanos , Doenças Metabólicas/veterinária , Neoplasias/veterinária , Intoxicação/veterinária , Animais , Mordeduras e Picadas/veterinária , Doenças Ósseas/veterinária , Doenças Cardiovasculares/veterinária , Gastroenteropatias/veterinária , Doenças Musculares/veterinária , Doenças do Sistema Nervoso/veterinária , Intoxicação por Plantas/veterinária , Doenças Respiratórias/veterinária , América do Sul , Doenças Urológicas/veterináriaRESUMO
A comparison of the performance of two epiphytes with crassulacean acid metabolism (CAM) was made during the rainy season and dry season at the Ciénega el Ostional, Chichiriviche in northern Venezuela. The epiphytic bromeliad, Tillandsia flexuosa has water-retaining tanks and leaf trichomes, and propagates mainly vegetatively to produce large populations in the shrubby island vegetation. The epiphytic orchid, Schomburgkia humboldtiana formed smaller populations, and had large succulent leaves with uniform chlorenchyma and no distinct water-storage parenchyma, unlike T. flexuosa. Both epiphytes were myrmecophilous. Leaf succulence (kg m-2 ) declined by â¼ 10% in the dry season for both plants. Both epiphytes showed reduced CO2 uptake during Phase I (dark period) and (dawn-dusk) titratable acidity (ΔH+ ) in the dry season. Water-use efficiency (WUE) was higher for S. humboldtiana (16.0 × 10-3 mol CO2 per mol H2 O compared with 5.0 × 10 -3 for T. flexuosa) although WUE remained constant during rainy and dry season for each species. Sixty to seventy per cent of the dawn dusk titratable acidity was derived internally from respiratory CO2 (recycling) for both species, and in absolute terms, recycling decreased in the dry season, in contrast to the expected progression under drought stress. Recycling is an important facet of carbon balance for both species in both rainy and dry seasons. Leaf Na+ concentration was higher than values quoted for terrestrial salt stressed CAM plants. Fructose and glucose declined in leaf bases of T. flexuosa during the dark period, but not in the more distal regions of the leaf. S. humboldtiana showed a decrease in sucrose at night, and mannitol was also an important constituent of the leaves. Xylem sap tension maxima increased from 0.38 ± 0.09 MPa (rainy season) to only 0.55 ± 0.06 MPa (dry season) for T. flexuosa, these values being much lower than those found for terrestrial shrubs and herbs at the same site, the two epiphytes use CAM in conjunction with differing morphological adaptations to maintain growth throughout the year at the Ciénega el Ostional, but it would seem that T. flexuosa has better physiological characteristics for maintenance of carbon acquisition during the dry season.
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Seasonal effects on leaf gas exchange and water relations were compared for Avicennia germinans, a true mangrove, and Conocarpus erectus, a mangrove associate, at coastal sites in northern Venezuela. On the Ciénega el Ostional at Chichiriviche, A. germinans was most abundant around lagoons on the seaward side of the vegetation-free alluvial sand plain. C. erectus was the dominant shrub in inland communities, but the two species co-occurred on vegetation islands at the landward edge of the alluvial plain. On the vegetation islands of the Ciénega el Ostional, gas exchange in A. germinans (a species with foliar salt glands) was less severely curtailed in the dry season compared with the rainy season than was gas exchange in C. erectus (a species lacking salt glands). Average rates of photosynthesis at near-saturating light intensities and total diurnal CO2 uptake were reduced in the dry season to 69 and 61%, respectively, of their values in the rainy for A. germinans, but to 48 and 30%, respectively, of their rainy-season values for C. erectus. Similarly, stomatal conductance and transpirational water loss were more reduced in the dry season for C. erectus than for A. germinans, with the result that C. erectus showed a 3.4-fold increase in water-use efficiency in the dry season compared with the rainy season. The importance of the soil environment in determining plant gas-exchange Patterns was evidenced by large seasonal shifts in dawn xylem tension for the two species (which increased from 1.34 MPa in the rainy season to 5.50 MPa in the dry season for A. germinans, and from 0.40 to 5.78 MPa for C. erectus). These values reflected changes in the soil environment caused by inundation of the upper soil layers by fresh water in the rainy season and a progressive increase in salt concentrations (to almost twice those in sea water) by evaporation from the soil in the dry season. Large changes in xylem tension were observed for both species during individual day-night cycles, reaching a maximum of 2.36 MPa for A. germinans. For C. erectus, the magnitude of these day-night changes was greatly reduced in the dry season, consistent with its very low transpiration rates at this time of year. Leaf-cell osmotic pressures also tended to be higher in A. germinans than C. erectus (attaining a maximum of 8.3 MPa for A. germinans in the dry season), and were related to the more seaward distribution of the true mangrove on the alluvial plain. Whereas leaves of A. germinans did not show any changes in succulence, leaf succulence in C. erectus increased with leafage and was slightly higher in the dry season than the rainy season. The more succulent leaves also had higher cell-sap osmotic pressures and NaCl concentrations. The most succulent leaves of C. erectus were observed for exposed shrubs growing on the shoreline. During the dry season, these shoreline plants showed high rates of gas exchange and low values for dawn xylem tension (0.89 MPa), indicating that they had access to relatively non-saline water from the shallow water table. On individual plants, exposed shoots had more succulent leaves and higher osmotic pressure and NaCl concentrations than sheltered leaves, demonstrating the importance of foliar absorption of salt borne in sea spray for the ionic relations of C. erectus. Thus, although the distribution of C. erectus is centred on brackish-water zones, this species can apparently extend from habitats with permanent access to a shallow water table through to areas where it is seasonally exposed to low soil water potentials and high salt concentrations in the substratum.
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The terrestrial CAM plant Bromelia humilis was examined in the salinas of the Ciénega el Ostional, on the north coast of Venezuela, in the rainy and dry seasons. Three colour forms were distinguished; yellow (in full sun), green exposed (also in sun) and green shaded (beneath woodland). Plant size decreased with increasing irradiance. An examination was made of the three phenotypes in terms of CO2 exchange (Jco2 ), dawn-dusk changes in titratable acidity (ΔH+ ) and malate and citrate levels, osmotic pressure, xylem tension, sugar and amino acids levels, nitrogen and ion concentrations and ambient temperature fluorescence. All phenotypes exhibited lowered Jco2 and ΔH+ in the dry as compared to the rainy season. Citrate, as well as malate, showed dawn-dusk fluctuations. Soluble sugars were the major source of carbon skeletons for nocturnal organic acid production. The dawn-dusk changes in osmotic pressure were negligible. Yellow plants performed poorly in contrast to shaded plants in both seasons. The former showed higher dawn-dusk changes of citrate levels and contained much less nitrogen than shaded plants. Nocturnal recycling of respiratory CO2 was more important in yellow plants and, in the dry season, reached 87%. These differences were reflected in the overall productivity, shaded plants showing increases in size whereas yellow plants utilized energy mainly for leaf replacement. Water availability and nitrogen supply appear to be the overriding factors determining higher productivity and CO2 assimilation in partially shaded plants as compared with plants in full sun.
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The perennial halophytes, Batis maritima L., Sesuvium portulacastrum L., and Portulaca rubricaulis H.B.K. which inhabit the extreme environment on parts of the salt plain and at the edges of the vegetation islands of Ciénega el Ostional were examined to determine their strategies for growth and survival in the rainy and dry seasons. All of the three species are leaf-succulents. High leaf-sap osmotic pressures, xylem tensions and Na+ and Cl- levels indicated that S. portulacastrum and B. maritima are salt-accumulating halophytes. Succulence, leaf-sap osmolalities and Na+ and Cl- levels increased in the dry season in B. maritima by a factor of 1.5-2.0 and in S. Portulacastrum by a factor of 1.9-2.7. B. maritima also accumulated sulphate with a two-fold increase of concentrations in the dry season. In S. portulacastrum Na+ accumulation much exceeded Cl- accumulation and oxalate synthesis was found to serve charge balance. In this species the compatible solutes, proline and pinitol, were clearly detectable in both seasons; their levels increased by a factor of about 6 in the dry season. Exchange of water vapour and CO2 was measured with a portable steady-state porometer. Photosynthesis in B. maritima showed little response to the transition from the rainy to the dry season while S. portulacastrum was severely impaired in the dry season, showing pronounced midday depressions of gas exchange and about 40% inhibition of light-saturated rates of CO2 uptake. P. rubricaulis shed its leaves in the dry season. According to carbon isotope ratios (δ13 C), B. maritima (δ13 C =-26.4) and S. portulacastrum (δ13 C =-25.8 ) are C3 plants while P. rubricaulis (δ13 C =-12.3) performed C4 photosynthesis.
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This paper describes the ecology of a coastal alluvial plain at Chichiriviche in northern Venezuela. The area supports a great diversity of plant communities, ranging from mangroves on the seaward edge of the plain to non-halophytic, fresh-water communities on the landward side. Small differences on topography result in a mosaic of saline and less-saline environments. Rainfall is strongly seasonal, causing superficial flooding of the alluvial plain in the rainy season and the creation of a hypersaline Substratum during the dry season. As a consequence, much of the plain is devoid or vegetation. Towards the landward side of the plain there are numerous small 'vegetation islands', fringed by halophilic succulent herbs, and made up of deciduous and semi-deciduous shrubs and trees together with non-halophytic CAM plants such as cacti and bromeliads. In subsequent papers the results of ecophysiological studies of these diverse plant species are presented.
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In an ecophysiological field investigation of plant communities of vegetation islands of an alluvial plain in northern Venezuela the members of the Cactaceae, Pereskia guamacho, and a columnar ceroid cactus, Subpilosocereus ottonis, were studied. The alluvial plain was flooded by fresh water in the rainy season in November/December 1985 and was dry and saline in the dry season in March/April 1986. The highly succulent leaves of P. guamacho were shed in the dry season. They performed C3 photosynthesis in the wet season and did not show signs of considerable salt accumulation. P. guamacho avoids stress due to drought and salinity by leaf-shedding. The columnar stem succulent ceroids are salt-excluding plants with crassulacean acid metabolism (CAM). Rapid die back and regeneration of absorptive roots, water parenchyma and CAM, with the possibility of nocturnal stomatal closure and CO2 recycling, are traits of adaptive value under fluctuating conditions between rainy and dry seasons on the alluvial plain.