RESUMO
BACKGROUND AND AIM: The aim of this study is to evaluate the clinical, biological and hematological profiles of autoimmune hemolytic anemia (AIHA) in children and to specify its etiologies, therapeutic modalities, and treatment responses. METHODS: This is a 14-year retrospective study of AIHA cases collected at the department of pediatric emergency and reanimation of Hedi Chaker University Hospital in Sfax. We included patients under 14 years old with clinical and biological features of hemolysis and a positive direct antiglobulin test (DAT). The selected patients' demographic characteristics, physical signs, laboratory findings, and treatment responses were recorded. RESULTS: Thirteen cases of AIHA were collected, including 8 girls and 5 boys. The median age at diagnosis was 4 years and 6 months (range: 8 months to 13 years). Consanguinity was reported in 6 cases and 4 patients had a previous infection history. The onset of AIHA was progressive in 9 cases, marked by an anemic syndrome and hemolysis symptoms in 6 and 8 cases, respectively. The clinical triad (pallor, jaundice and splenomegaly) was found in only 4 cases. At the time of diagnosis, the median hemoglobin (Hb) level was 6g/dL (range: 4.2 to 9.2g/dL), anemia was non-regenerative in 2 patients. Thrombocytopenia and neutropenia were noted in 5 and 1 patient, respectively. Peripheral smear examination showed spherocytosis in 2 cases. All the patients had a positive DAT. Of these, 10 were positive with IgG and 3 with both IgG and C3d. AIHA was secondary to other conditions in 9 patients: infection (3 cases), autoimmune disease (4 cases), and immunodeficiency (2 cases). All the patients received first-line corticosteroid therapy but only 8 of them required blood transfusions due to severe anemia. Complete remission was obtained in 7 cases. Corticosteroid resistance and dependence were noted in 1 and 2 cases, respectively. During evolution, additional therapy was indicated in 4 patients and it included cyclosporine A, azathioprine, and mycophenolate mofetil (MMF). After a median follow-up of 4.5 years, the cure rate was 80% and only 1 patient (a boy) died due to his underlying pathology. CONCLUSION: Our study highlights the rarity, severity, and heterogeneity of etiological contexts of AIHA in children. The therapeutic difficulties justify specific expertise in pediatric hematology.
Assuntos
Anemia Hemolítica Autoimune , Leucopenia , Trombocitopenia , Adolescente , Anemia Hemolítica Autoimune/diagnóstico , Anemia Hemolítica Autoimune/terapia , Criança , Feminino , Hemólise , Humanos , Masculino , Estudos RetrospectivosRESUMO
BACKGROUND: Severe combined immunodeficiency (SCID) is a the most severe form of primary immunodeficiency and is highly heterogeneous. We report an atypical form of SCID revealed by exfoliative erythroderma. PATIENTS AND METHODS: A 3-month-old boy, born to consanguineous parents, was admitted to the dermatology department with exfoliative erythroderma associated with eczematous patches and alopecia of the scalp, eyelashes, and eyebrows, but with no lymphadenopathy or hepatosplenomegaly. He displayed chronic diarrhea and recurrent infection since birth. A complete blood count showed marked leukocytosis with eosinophilia and lymphocytosis. These clinical and biological findings improved partly with topical steroids. The patient no longer had erythroderma and showed regrowth of hair, eyelashes and eyebrows. The subsequent CBC showed less marked eosinophilia with mild lymphopenia and no leukocytosis. Immunoglobulin levels were undetectable. Primary immunodeficiency was discussed. Immunological investigations concluded on a diagnosis of T-B-NK+ SCID. Mutation analysis revealed a homozygous c.1338C>G (pCys446Trp) mutation in the RAG2 gene. Hematopoietic stem cell transplantation is planned in the near future. CONCLUSION: This case illustrates atypical T-B-NK+ SCID revealed by severe exfoliative erythroderma in a 3-month-old boy with RAG2 gene mutation. Neonatal erythroderma must be considered a warning sign of primary immunodeficiency requiring immediate immunological phenotyping as well as genetic testing for a definitive diagnosis.
Assuntos
Dermatite Esfoliativa/etiologia , Imunodeficiência Combinada Severa/complicações , Alopecia/etiologia , Alopecia/patologia , Doença Crônica , Consanguinidade , Proteínas de Ligação a DNA/genética , Dermatite Esfoliativa/patologia , Diarreia/etiologia , Eczema/etiologia , Eczema/patologia , Transplante de Células-Tronco Hematopoéticas , Humanos , Lactente , Masculino , Proteínas Nucleares/genética , Fotografação , Imunodeficiência Combinada Severa/genética , Imunodeficiência Combinada Severa/terapiaRESUMO
Autoimmune lymphoproliferative syndrome (ALPS) is a prototypic disorder of impaired apoptosis characterized by autoimmune features and lymphoproliferation. Heterozygous germline or somatic FAS mutations associated with preserved protein expression have been described. Very rare cases of homozygous germline FAS mutations causing severe autosomal recessive form of ALPS with a complete defect of Fas expression have been reported. We report two unrelated patients from highly inbred North African population showing a severe ALPS phenotype and an undetectable Fas surface expression. Two novel homozygous mutations have been identified underlying rare splicing defects mechanisms. The first mutation breaks a branch point sequence and the second alters a regulatory exonic splicing site. These splicing defects induce the skipping of exon 6 encoding the transmembrane domain of CD95. Our findings highlight the requirement of tight regulation of FAS exon 6 splicing for balanced alternative splicing and illustrate the importance of such studies in highly consanguineous populations.
Assuntos
Processamento Alternativo/genética , Síndrome Linfoproliferativa Autoimune/genética , Receptor fas/genética , Síndrome Linfoproliferativa Autoimune/sangue , Western Blotting , Consanguinidade , Proteína Ligante Fas/sangue , Mutação em Linhagem Germinativa , Humanos , Lactente , Interleucina-10/sangue , Líbia , Masculino , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Índice de Gravidade de Doença , Tunísia , Receptor fas/sangueRESUMO
BACKGROUND: Chronic granulomatous disease is a rare inherited primary immune deficiency disease characterized by recurrent infection and an increased susceptibility to autoimmunity disorders. We report on the case of a girl with autoimmune hepatitis in chronic granulomatous disease to describe the clinical and biological features and treatment implications for patients with chronic granulomatous disease associated with autoimmune disorders. CASE REPORT: An 18-month-old girl was referred to our department for investigation of hepatomegaly. She was the third child of non-consanguineous parents. Her two elder sisters had died from infectious diseases at an early age. She had elevated liver transaminase levels with a normal gamma globulin concentration. Negative results were found for all autoimmune markers (antinuclear antibody, anti-smooth muscle, anti-liver-kidney microsomal, anti-liver cytosol and anti-soluble liver antigen). Her liver biopsy showed features of interface hepatitis with portal fibrosis. The diagnosis of seronegative autoimmune hepatitis was established. Treatment with corticosteroids and azathioprine led to clinical improvement with normalization of transaminases. Six months after initial presentation, at the age of 2 years, she was readmitted for fever. Staphylococcus aureus bacteremia was identified with multiple foci of infection (skin infection, arthritis of the right elbow, pneumonia, buttock abscess). The immunological workup revealed chronic granulomatous disease. The course was marked by a fatal outcome despite appropriate antibiotics and intensive care. CONCLUSION: Early diagnosis of the association between chronic granulomatous disease and autoimmune disorders allows for appropriate treatments, improves the quality of life for affected patients, and reduces the risk of mortality.
Assuntos
Doença Granulomatosa Crônica/diagnóstico , Hepatite Autoimune/diagnóstico , Antibacterianos/uso terapêutico , Bacteriemia/diagnóstico , Pré-Escolar , Cuidados Críticos , Evolução Fatal , Feminino , Seguimentos , Doença Granulomatosa Crônica/genética , Doença Granulomatosa Crônica/terapia , Hepatite Autoimune/genética , Hepatite Autoimune/terapia , Humanos , Lactente , Infecções Estafilocócicas/diagnósticoRESUMO
Pneumocystis pneumonia is a severe opportunistic infection in immunocompromised patients, caused by Pneumocystis jirovecii (P. jirovecii). The co-infection with community-acquired P. jirovecii and Mycobacterium tuberculosis (M. tuberculosis) is exceptionally described in non immunocompromised patients. We herein report the case of a young woman, with no medical history, who developed an acute respiratory failure due to P. jirovecii pneumonia associated with miliary tuberculosis. An extensive immunological investigation ruled out any acquired or primary immunodeficiency, suggesting that she was most likely immunocompetent. This report shows that such infections are not restricted to immunocompromised hosts. Moreover, it is tempting to speculate that the development of M. tuberculosis infection in this patient could be a risk factor for transition from colonization status of respiratory tract by P. jirovecii to pneumocystosis.
Assuntos
Pneumocystis carinii , Pneumonia por Pneumocystis/complicações , Tuberculose/complicações , Coinfecção , Feminino , Humanos , Imunocompetência , Adulto JovemRESUMO
This present case report describes two siblings with severe type V hyperlipoproteinaemia, diagnosed very early in life and due to the combination of the common apolipoprotein (Apo) E2 allele and rare mutant variant of ApoE, ApoE3 (Arg 136-->Ser). Phenotyping of ApoE falsely identified E2/E2 phenotype. The presence of mutated ApoE was suspected on an unusual restriction polymorphism of a Hha 1 restriction site and confirmed by sequence analysis of the cloned polymerase chain reaction fragment of exon 4 and familial segregation study. The severity of the hypertriacylglycerolaemia was modulated by the lipid content of the diet. A low-fat diet enriched in medium-chain triacylglycerol (TAG) decreased but did not normalize plasma TAG levels in both affected patients of the pedigree. A standardized lipid-enriched test meal showed a marked impairment of TAG-rich lipoprotein (TRL) clearance, especially the exogeneous TRL bearing ApoB-48 which still represented 79% of total TRL 7 h after the fat load. Finally, differences between the male and female siblings with the existence of a consanguine relationship in their parents suggested the involvement of other genetic factors in modulating the severity of phenotypic expression. This observation reinforces the usefulness of genotyping of ApoE for the characterization of genetic hypertriacylglycerolaemia and selection of the appropriate diet and treatment.
Assuntos
Apolipoproteínas E/genética , Hiperlipoproteinemia Tipo V/genética , Mutação Puntual/genética , Adulto , Apolipoproteínas E/sangue , Dieta com Restrição de Gorduras , Gorduras na Dieta/metabolismo , Feminino , Seguimentos , Humanos , Hiperlipoproteinemia Tipo V/dietoterapia , Hiperlipoproteinemia Tipo V/metabolismo , Lipoproteínas/sangue , Lipoproteínas/farmacocinética , Masculino , Triglicerídeos/sangue , Triglicerídeos/químicaAssuntos
Cardiopatias Congênitas/epidemiologia , Cardiopatias Congênitas/etiologia , Distribuição por Idade , Criança , Consanguinidade , Progressão da Doença , Feminino , Cardiopatias Congênitas/diagnóstico , Cardiopatias Congênitas/cirurgia , Departamentos Hospitalares , Humanos , Lactente , Mortalidade Infantil , Recém-Nascido , Masculino , Pediatria , Estudos Retrospectivos , Fatores de Risco , Distribuição por Sexo , Tunísia/epidemiologiaRESUMO
We know that upper body obesity is associated with metabolic complications, but we don't know how regional body fat distribution influences postprandial lipemia in obese adults. Thus, this study explored the respective effects of android or gynoid types of obesity and fasting triglyceridemia on postprandial lipid metabolism and especially triglyceride-rich lipoproteins. Twenty-four obese and 6 lean normotriglyceridemic women (control), age 24-57 yr, were enrolled. Among obese women with an android phenotype, 9 exhibited normal plasma triglyceride levels (mean: 1.38 mmol/L) (NTAO), and 7 displayed a frank hypertriglyceridemia (mean: 2.40 mmol/L) (HTAO). The 8 patients with a gynoid phenotype had normal triglyceride levels (mean: 1.00 mmol/L) (GO). All were given a mixed test meal providing 40 g triglycerides. Serum and incremental chylomicron triglycerides 0-7 h areas under the curve (AUCs) as well as triglyceride levels in apoB-48-containing triglyceride-rich lipoprotein (TRLs) or chylomicrons were significantly higher in HTAOs and NTAOs than in GOs and controls postprandially. The size of chylomicron particles was bigger in controls and GOs than in HTAOs and NTAOs postprandially. Android obese subjects showed abnormally elevated fasting apoB-48 and apoB-100 triglyceride-rich lipoprotein (TRL) levels. Most abnormalities that were found correlated to plasma levels of insulin and apoC-III. In conclusion, an abnormal postprandial lipid pattern is a trait of abdominal obesity even without fasting hypertriglyceridemia.
Assuntos
Tecido Adiposo/metabolismo , Obesidade/sangue , Período Pós-Prandial/fisiologia , Triglicerídeos/sangue , Adulto , Apolipoproteína C-III , Apolipoproteínas C/sangue , Feminino , Humanos , Insulina/sangue , Mucosa Intestinal/metabolismo , Lipase Lipoproteica/sangue , Lipoproteínas/sangue , Fígado/metabolismo , Pessoa de Meia-IdadeRESUMO
The aim of this study was to assess the interindividual variability of chylomicron beta-carotene response to a pharmacological load of beta-carotene in the population, to identify the mechanisms responsible for this variability, and to evaluate its consequences on beta-carotene status and metabolism. The variability, as estimated by the 3-h chylomicron beta-carotene response to 120 mg beta-carotene in 79 healthy male volunteers, was high (CV = 61%), but it was unimodal and all the subjects had detectable chylomicron beta-carotene. In 16 subjects randomly selected among the 79, the interindividual variability of the triglyceride-adjusted chylomicron (beta-carotene + retinyl palmitate) response (0-12.5 h area under the curve) was high (CV = 54%), suggesting that there is a high interindividual variability in the efficiency of intestinal absorption of beta-carotene. The chylomicron beta-carotene response was correlated (r = 0.50, P < 0.05) with the chylomicron triglyceride response. The beta-carotene status, as assessed by beta-carotene concentration in buccal mucosal cells, was correlated (r = 0.73, P < 0.05) with the triglyceride-adjusted chylomicron beta-carotene response, i.e., with the ability to respond to beta-carotene. The triglyceride-adjusted chylomicron retinyl-palmitate response was correlated (r = 0.55, P < 0.05) with the triglyceride-adjusted chylomicron beta-carotene response. Plasma all-trans retinoic acid slightly, but significantly, increased (+40%) 3 h after the beta-carotene load, but this increase was not related to the triglyceride-adjusted beta-carotene response. In conclusion, the ability to respond to beta-carotene is highly variable, but there is probably a very small proportion of true non-responders to pharmacological doses of beta-carotene in the healthy population. This variability is apparently mainly due to interindividual differences in the efficiency of intestinal absorption of beta-carotene and in chylomicron metabolism. The ability to respond to beta-carotene can affect the beta-carotene status and the provitamin A activity of beta-carotene, but it has apparently no effect on the amount of retinoic acid appearing in the plasma after the ingestion of a pharmacological dose of beta-carotene.
Assuntos
Antioxidantes/farmacologia , beta Caroteno/farmacologia , Administração Oral , Adulto , Quilomícrons/sangue , Relação Dose-Resposta a Droga , Ingestão de Energia , Comportamento Alimentar , Humanos , Isotretinoína/sangue , Masculino , Tretinoína/sangue , beta Caroteno/administração & dosagemRESUMO
The effect of the ingestion of beta-carotene with medium-chain triglycerides (MCT) or long-chain triglycerides (LCT) on the bioavailability and the provitamin A activity of beta-carotene was investigated in humans. Sixteen healthy young men ingested, on two different days, a test meal containing 120 mg beta-carotene incorporated into 40 g LCT (LCT meal) or 40 g MCT (MCT meal). This meal was followed 6 h later by a beta-carotene-free meal containing 40 g LCT. Chylomicron beta-carotene, retinyl palmitate and triglycerides were measured every hour for 12.5 h after the first meal. No significant increase in chylomicron triglycerides was detected for the 6 h after the MCT meal intake, whereas a significant increase in chylomicron triglycerides was observed after the LCT meal intake. The chylomicron beta-carotene and retinyl palmitate responses to the MCT meal (0-6 h area under the curves, AUC) were significantly (P < 0.05) lower [AUC = 68.1 +/- 26.8 and 43. 4 +/- 10.4 nmol/(L.h), for beta-carotene and retinyl palmitate, respectively] than those obtained after the LCT meal [301.4 +/- 64.0 and 166.0 +/- 29.0 nmol/(L.h), respectively]. The chylomicron beta-carotene and retinyl palmitate responses obtained after the beta-carotene-free meal (6-12.5 h AUC) were also significantly lower when the first meal provided MCT rather than LCT. The chylomicron (retinyl palmitate/beta-carotene) ratios were constant during the postprandial periods, whatever the meal ingested. We conclude that the chylomicron beta-carotene response is markedly diminished when beta-carotene is absorbed with MCT instead of LCT. This phenomenon is apparently due to the lack of secretion of chylomicrons in response to MCT; however, a lower intestinal absorption of beta-carotene or a higher transport of beta-carotene via the portal way in the presence of MCT cannot be ruled out. Finally, the data obtained show that MCT do not affect the rate of intestinal conversion of beta-carotene into vitamin A.
Assuntos
Quilomícrons/metabolismo , Triglicerídeos/administração & dosagem , Vitamina A/análogos & derivados , beta Caroteno/administração & dosagem , beta Caroteno/farmacocinética , Adulto , Disponibilidade Biológica , Diterpenos , Interações Medicamentosas , Alimentos , Humanos , Cinética , Masculino , Ésteres de Retinil , Triglicerídeos/sangue , Triglicerídeos/química , Vitamina A/sangue , beta Caroteno/sangueRESUMO
To assess the influence of age on vitamin A intestinal and liver metabolism in humans, the postprandial plasma concentrations of intestinal-originated vitamin A, i.e., retinyl esters, and liver-originated vitamin A, i.e., retinol, were compared in eight young (20-30 years old) and eight elderly (64-72 years old) healthy men. Plasma and chylomicron retinyl esters and retinol concentrations were measured for up to 24 h following the intake of a test meal that contained 23,300 RE retinyl palmitate. The chylomicron retinyl palmitate response (area under the curve) was not significantly different between the two groups, but its peak was slightly delayed (1 h) in the elderly men. The proportion of the different retinyl esters secreted in the chylomicrons was not significantly different between the two groups. The postprandial plasma retinol concentration did not change in the young participants, whereas it significantly increased in the elderly. These results suggest that vitamin A intestinal absorption and retinol intestinal esterification processes are not markedly modified in the elderly, whereas the chylomicron clearance and the regulation of postprandial plasma retinol concentration are apparently altered in these subjects.
Assuntos
Envelhecimento/sangue , Ingestão de Alimentos/fisiologia , Vitamina A/sangue , Adulto , Idoso , Quilomícrons/sangue , Diterpenos , Jejum , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Concentração Osmolar , Ésteres de Retinil , Triglicerídeos/sangue , Vitamina A/análogos & derivadosRESUMO
The aim of this study was to evaluate the cholesterol-lowering effects of reducing fat and increasing or not increasing dietary fiber in subjects consuming a mixed Mediterranean-Western diet. Thirty-one free-living, mildly hypercholesterolemic subjects were randomly allocated to two groups. Subjects in both groups first shifted for 4 wk to a low-fat, low-fiber diet (LFLFD). For an additional 4-wk period, subjects in group 1 continued consuming the LFLFD whereas subjects in group 2 consumed a low-fat, high-fiber diet (LFHFD). Most dietary fatty acids were monounsaturated (38-41%) and fibers, when provided (up to 35 g/d), came from unrefined cereals, legumes, and soluble-fiber-enriched ready-to-eat cereals. After period 1 of the LFLFD, mean serum and low-density-lipoprotein (LDL)-cholesterol concentrations of subjects in groups 1 (-12.5% and -15.5%, respectively) and 2 (-10.5% and -15.5%, respectively) decreased significantly from baseline (P < 0.05). After period 2, mean serum and LDL-cholesterol concentrations of subjects consuming the LFLFD (group 1) were still lower (by 8.8% and 9.2%, respectively, from baseline) whereas in subjects consuming the LFHFD (group 2) these values decreased further to significantly lower values (14.2% and 17.6% from baseline, respectively). Fasting high-density-lipoprotein (HDL) cholesterol, apolipoprotein A-I, glycemia, and insulinemia did not change significantly. In seven men, postprandial lipemia transiently increased more after a breakfast test meal at the completion of the LFHFD period than after the LFLFD period. In conclusion, an LFHFD more comparable with the traditional Mediterranean diet may improve the dietary management of moderate hypercholesterolemia.
Assuntos
Gorduras na Dieta/administração & dosagem , Fibras na Dieta/administração & dosagem , Hipercolesterolemia/sangue , Lipídeos/sangue , Adulto , Idoso , Glicemia , Índice de Massa Corporal , Peso Corporal , Feminino , Humanos , Hipercolesterolemia/dietoterapia , Insulina/sangue , Masculino , Região do Mediterrâneo , Pessoa de Meia-Idade , Período Pós-PrandialRESUMO
OBJECTIVE: Assessing the effect of the dose of dietary triglycerides on preformed vitamin A (retinyl esters) bioavailability in humans. DESIGN: Four test meals containing 15,000 RE retinyl-palmitate and either 0, 15, 30 or 40 g added triglycerides were ingested by eight healthy volunteers, at different days and in a randomized order. SETTING: The study was done in the Hospital Sainte Marguerite, Marseille, France. SUBJECTS: Eight healthy male volunteers were recruited by advertisement. INTERVENTION: Blood samples were collected every hour for seven hours after the test meals intake. Serum and chylomicron (Svedberg flotation unit > 1000) were prepared by centrifugation and retinyl esters were measured by HPLC. RESULTS: The serum retinyl ester response was not significantly lower after the intake of the meal without added triglycerides (7944 +/- 3262 nmol/L h) than after the intake of the fat meals (10012 +/- 2182, 7869 +/- 3157 and 10777 +/- 2067 nmol/L h for the 15, 30 and 40 g-fat meal, respectively), indicating that the serum retinyl ester response was not related to the amount of meal triglycerides. Chylomicron retinyl linoleate response stepwise increased when the amount of meal triglycerides increased while retinyl palmitate and retinyl stearate responses reached a maximum since 15 g triglycerides. Postprandial serum retinol concentration did not change whatever the meal ingested. CONCLUSIONS: (i) a significant amount of preformed vitamin A is apparently absorbed when ingested with trace amount of meal triglycerides only; (ii) meal triglycerides, up to 40 g/meal, do not increase preformed vitamin A bioavailability; (iii) the retinyl ester pattern recovered in the chylomicrons, and probably the esterification process of retinol, is affected by the amount of meal triglycerides; (iv) postprandial retinol homeostasis is not affected by dietary triglycerides.
Assuntos
Triglicerídeos/farmacologia , Vitamina A/farmacocinética , Adulto , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão , Quilomícrons/metabolismo , Dieta , Relação Dose-Resposta a Droga , Humanos , Masculino , Período Pós-Prandial , Triglicerídeos/administração & dosagem , Vitamina A/sangueRESUMO
The effect of ageing on vitamin E bioavailability in humans was assessed by comparing chylomicron and plasma alpha-tocopherol postprandial concentrations after a dose of vitamin E (432 or 937 IU as d1-alpha-tocopherol acetate), in eight young (20-30 years old) and eight healthy elderly men (64-72 years old). The fasting plasma alpha-tocopherol concentration was significantly higher in the elderly (33 +/- 2 mumol L-1) than in the young (22 +/- 2 mumol L-1). In both groups, the plasma and chylomicron alpha-tocopherol postprandial concentrations were significantly, approximately twofold, higher after the 937-IU meal than after the 432-IU meal. For both test meals, the chylomicron alpha-tocopherol areas under the curve were significantly lower in the elderly than in the young subjects: 98.9 +/- 16.5 (young group) vs. 55.3 +/- 7.8 (elderly group) mumol L-1 h for the 937-IU test meal and 60.4 +/- 14.1 (young group) vs. 26.0 +/- 7.6 (elderly group) mumol L-1 h for the 432-IU test meal, whereas the plasma alpha-tocopherol area under the curve was significantly higher in elderly than in young subjects: 337.56 +/- 16.11 (937-IU test meal) vs. 159.81 +/- 35.55 (432-IU test meal) mumol L-1 h in the young group and 709.55 +/- 69.33 (937-IU test meal) vs. 436.39 +/- 41.08 (432-IU test meal) mumol L-1 h in the elderly group. We concluded that (a) the amount of vitamin E appearing in plasma is proportional to the dose ingested (up to 937 IU); (b) the intestinal absorption of vitamin E is not increased, even possibly decreased, in the elderly; and (c) the amount of vitamin E transported by non-chylomicron lipoproteins is apparently higher in the elderly. This suggests that vitamin E postprandial transport is affected by ageing, mainly as the consequence of age-related modifications of lipoprotein metabolism.
Assuntos
Quilomícrons/sangue , Período Pós-Prandial , Vitamina E/sangue , Adulto , Fatores Etários , Idoso , Disponibilidade Biológica , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Vitamina A/sangueRESUMO
To investigate the mechanisms behind the serum cholesterol-lowering effect of oat fiber, we simultaneously measured postprandial lipid responses, serum lathosterol concentrations, and small bowel excretion of fat and sterols in ileostomy subjects given test meals high or low in oat fiber. Six ileostomy subjects (three women and three men) were served an oat-bran test meal (OB; 16.3 g fiber) and a wheat test meal (6.3 g fiber) in random order. After the postprandial 7-h period, a controlled, low-fat, cholesterol-free diet was served and ileostomy effluent was sampled throughout the 24-h period. Bile acid and fat excretion (24 h) increased by 93% and 146%, respectively (P < 0.05), and total and endogenous cholesterol excretion decreased by 14% and 19%, respectively (P < 0.05), after the OB test meal. The change in hepatic cholesterol synthesis was strongly related to the change in bile acid excretion (Spearman r = 0.89, P < 0.02). The postprandial chylomicron lipid concentration tended to be lower after the OB test meal (-43% for cholesterol, P = 0.07) whereas there was no difference in cholesterol absorption measured by isotope in five subjects. The main effect of the viscous oat beta-glucan seems to be related to increased bile acid excretion and subsequent changes in synthesis and endogenous excretion of cholesterol. An additional effect may have been a delay in the micellar lipid solubilization process and a consequent reduction in the secretion of chylomicrons into the circulation.
Assuntos
Colesterol/metabolismo , Fibras na Dieta/administração & dosagem , Ileostomia , Lipídeos/sangue , Período Pós-Prandial , Adulto , Apolipoproteínas E/genética , Avena , Colesterol/biossíntese , Colesterol/sangue , Gorduras na Dieta/análise , Fezes/química , Feminino , Humanos , Insulina/sangue , Lipase/sangue , Lipídeos/análise , Lipase Lipoproteica/sangue , Fígado/enzimologia , Masculino , Pessoa de Meia-Idade , Fenótipo , TriticumRESUMO
The physiological effects of dietary fibres in humans are due to their physico-chemical properties. However, it is difficult to predict these effects simply by measuring certain characteristics in vitro. Studies in human subjects are still required to assess the effectiveness of new substrates. The aim of the present study in healthy human subjects was to evaluate the effects of two novel fibres, potato (PF) and maize (MF), on fasting and postprandial blood concentrations of carbohydrate and lipid metabolites as well as on stool output and transit time. The chemical composition, water-binding capacity (WBC) and fermentative properties of the fibres were also characterized in order to determine their possible involvement in digestive and metabolic effects. Stools, as well as breath and blood samples, were collected after consumption for 1 month of either a basal diet (control) or a basal diet supplemented with fibre (15 g/d). MF resisted fermentation better than PF and had lower digestibility. However, both fibres increased faecal output of dry matter, neutral sugars and water. There was an inverse relationship between stool weight and orofaecal transit time, although only MF significantly reduced transit time. Orocaecal transit was lengthened by PF, probably because of its high WBC. PF ingestion also decreased postprandial plasma levels of total and esterified cholesterol but had no effect on fasting concentrations. In contrast, MF lowered fasting cholesterolaemia and increased free:esterified cholesterol. These particular physiological and fermentative properties suggest that PF and MF would be suitable ingredients in a healthy diet.
Assuntos
Carboidratos/sangue , Fibras na Dieta/administração & dosagem , Digestão/fisiologia , Lipídeos/sangue , Solanum tuberosum , Zea mays , Adulto , Colesterol/sangue , Jejum/fisiologia , Ácidos Graxos Voláteis/metabolismo , Fezes/química , Feminino , Trânsito Gastrointestinal , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Prandial , Água/metabolismoRESUMO
Our aim was to determine the effects of increasing amounts of dietary cholesterol (0-710 mg) on the postprandial plasma lipid responses and lipoprotein changes in normolipidemic human subjects. Ten subjects were fed five different test meals in a random order: one meal did not contain fat or cholesterol while the four others contained a fixed amount of lipids (45 g) and 0, 140, 280, and 710 mg cholesterol, respectively. Fasting and post-meal blood samples were obtained for 7 h. Large and small triglyceride-rich lipoproteins (TRL), low density (LDL), and high density (HDL) lipoproteins were isolated. Compared to the no-fat, no-cholesterol meal, the fat-enriched meals raised (P < 0.05) plasma triglycerides, phospholipids, and free cholesterol and lowered cholesteryl esters postprandially. The meals containing zero or 140 mg cholesterol generally elicited comparable postprandial plasma and lipoprotein lipid responses. The meals providing 280 or 710 mg cholesterol significantly increased postprandial plasma phospholipids and large TRL triglycerides and decreased plasma esterified cholesterol. The lipid composition of the large TRLs and the concentrations of the small TRL lipid components were not altered postprandially by cholesterol intake. On the other hand, LDL free cholesterol increased after 3 h, LDL cholesteryl esters dropped after 3 and 7 h, HDL cholesteryl esters dropped after 3 h, and HDL phospholipids increased 7 h after ingesting meals highly enriched in cholesterol. Blood insulin, apoA-I and apoB were not altered postprandially by cholesterol intake. Thus, the data show that ingesting more than 140 mg cholesterol per meal significantly alters the postprandial lipoprotein response in healthy subjects.
Assuntos
Colesterol na Dieta/administração & dosagem , Alimentos , Lipídeos/sangue , Lipoproteínas/sangue , Adulto , Colesterol/sangue , Ésteres do Colesterol/sangue , Humanos , Cinética , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Lipoproteínas VLDL/sangue , Masculino , Triglicerídeos/sangueRESUMO
Iron status was assessed using a combination of several biochemical indicators (serum ferritin, erythrocyte protoporphyrin, serum iron, MCV, hemoglobin) in 3,676 apparently healthy children. Children who were 10 months, 2 years and 4 years of age were selected from the population undergoing a free medical check up in a Paris Child Health Center. The prevalence of iron deficiency in children of parents from continental France was 29% in the 10 month olds, 13% in the 2 year olds and 7% in those who were 4 years of age. Corresponding figures in children born of immigrant parents were 50%, 44% and 15% respectively. Iron deficiency anemia was found in 8% of 10 month olds from continental France versus 23% in the other group. Children born of parents from the South Sahara were found to be at high risk for iron deficiency.
Assuntos
Anemia Hipocrômica/sangue , Deficiências de Ferro , Fatores Etários , Anemia Hipocrômica/etnologia , Pré-Escolar , Feminino , Humanos , Lactente , Ferro/sangue , Masculino , Paris , Distribuição Aleatória , MigrantesRESUMO
Prevalence of anemia was estimated by two methods in 1235 healthy children 10 months old undergoing a free-of-charge medical checkup in a Parisian Child Health Examination Center. According to the classical method, the frequency of anemia, defined as the percentage of children with hemoglobin concentration below the WHO cut-off point (11 g/dl), amounts to 16.8% of 797 French children, 24.0% of 289 North African children and 43.6% of 149 sub-saharan children. The second method defines the frequency of anemia as the percentage of children whose hemoglobin values are shifted downwards relative to a gaussian hemoglobin distribution in non-anemic children. According to this method, anemia was present in 0.8%, 5.4% and 12.6% of children, respectively. The conventional cut-off point probably tends to overestimate the true frequency of anemia in this age group.
Assuntos
Anemia Hipocrômica/epidemiologia , Hemoglobinas/análise , África do Norte , África Austral , Anemia Hipocrômica/diagnóstico , Feminino , França , Humanos , Lactente , Masculino , Valores de ReferênciaRESUMO
Indicators of iron status, markers of inflammatory processes, serum immunoglobulins and C3 and C4 components of complement were assessed in 142 children 10-months old. All the iron parameters and most of the indicators of humoral immunity were correlated with markers of inflammation. Sixty-two children presented biochemical indications of inflammation (high CRP or orosomucoid level, or hyperleukocytosis), while 80 children were free of it. In the latter group, the use of a combination of iron indicators enabled separation of iron-sufficient children from those with different degrees of iron deficiency, ranging from iron depletion to iron-deficiency anemia. Serum IgG and IgA were significantly lower only in the group of iron-depleted children. Serum ferritin was significantly positively correlated with IgA, IgM and C4. Iron depletion may be responsible for a decrease humoral immunity. This effect was not visible at more advanced stages of iron deficiency.