Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 27
Filtrar
2.
Curr Opin Crit Care ; 24(4): 248-255, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29864039

RESUMO

PURPOSE OF REVIEW: Hypovitaminosis C and vitamin C deficiency are very common in critically ill patients due to increased needs and decreased intake. Because vitamin C has pleiotropic functions, deficiency can aggravate the severity of illness and hamper recovery. RECENT FINDINGS: Vitamin C is a key circulating antioxidant with anti-inflammatory and immune-supporting effects, and a cofactor for important mono and dioxygenase enzymes. An increasing number of preclinical studies in trauma, ischemia/reperfusion, and sepsis models show that vitamin C administered at pharmacological doses attenuates oxidative stress and inflammation, and restores endothelial and organ function. Older studies showed less organ dysfunction when vitamin C was administered in repletion dose (2-3 g intravenous vitamin C/day). Recent small controlled studies using pharmacological doses (6-16 g/day) suggest that vitamin C reduces vasopressor support and organ dysfunction, and may even decrease mortality. SUMMARY: A short course of intravenous vitamin C in pharmacological dose seems a promising, well tolerated, and cheap adjuvant therapy to modulate the overwhelming oxidative stress in severe sepsis, trauma, and reperfusion after ischemia. Large randomized controlled trials are necessary to provide more evidence before wide-scale implementation can be recommended.


Assuntos
Antioxidantes/administração & dosagem , Deficiência de Ácido Ascórbico/dietoterapia , Ácido Ascórbico/administração & dosagem , Cuidados Críticos , Estado Terminal/terapia , Estresse Oxidativo/efeitos dos fármacos , Ácido Ascórbico/sangue , Humanos , Necessidades Nutricionais/fisiologia , Escores de Disfunção Orgânica , Resultado do Tratamento
7.
Hemoglobin ; 40(4): 293-4, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27492769

RESUMO

Globally, ß-thalassemia major (ß-TM) is one of the most common hereditary disorders. Multiple blood transfusions, that are a life-saving therapy in patients with ß-TM, is a major source of iron overload. Iron overload can lead to significant morbidity and mortality. Research evidence indicates that oxidative stress induced by iron overload, is one of the major precipitating causes of vitamin C deficiency in ß-TM patients. It has previously been shown that patients with ß-TM have significantly lower levels of vitamin C as compared to healthy individuals. It is believed that vitamin C can reduce both ferric (Fe(3+)) and ferrous (Fe(2+)) ions, and also facilitate the accessibility of iron to chelators through increase of iron release from the reticuloendothelial system. Despite the potential benefits of vitamin C in patients with ß-TM, several areas of concern exist that should be addressed by high quality research designs. Some recommendations have been provided through this study.


Assuntos
Ácido Ascórbico/uso terapêutico , Talassemia beta/complicações , Deficiência de Ácido Ascórbico/dietoterapia , Deficiência de Ácido Ascórbico/etiologia , Contraindicações , Suplementos Nutricionais , Humanos , Sobrecarga de Ferro/etiologia , Política Nutricional , Estresse Oxidativo , Reação Transfusional , Talassemia beta/terapia
8.
BMJ Case Rep ; 20162016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26823349

RESUMO

A 10-year-old boy developed a perifollicular rash during interim maintenance of T-Cell acute lymphoblastic leukaemia. Differential diagnoses included drug reaction and inflammatory process. Before diagnosis, the patient had a limited diet--low in vegetables and fruits--due to selective eating, with later anorexia and taste aversions due to chemotherapy treatment. Despite nutritional counselling and starting a multivitamin, the patient incurred severe weight loss (18.5% of his usual body weight). Serum levels of ascorbic acid were non-detectable, at <5 µmol/L, indicative of vitamin C deficiency. The patient began vitamin C supplementation containing 125 mg ascorbic acid three times a day for 7 days, then 125 mg once daily for 3 months to normalise serum vitamin C. After ascorbic acid treatment was completed, the patient started a complete multivitamin and made efforts to eat fruits and vegetables rich in vitamin C. His serum ascorbic acid concentrations normalised to 52 µmol/L 3 months after receiving supplementation.


Assuntos
Deficiência de Ácido Ascórbico/dietoterapia , Ácido Ascórbico/administração & dosagem , Transtornos da Alimentação e da Ingestão de Alimentos/psicologia , Cooperação do Paciente/psicologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Vitaminas/administração & dosagem , Deficiência de Ácido Ascórbico/etiologia , Deficiência de Ácido Ascórbico/psicologia , Criança , Suplementos Nutricionais , Aconselhamento Diretivo/métodos , Ingestão de Energia , Transtornos da Alimentação e da Ingestão de Alimentos/dietoterapia , Transtornos da Alimentação e da Ingestão de Alimentos/etiologia , Frutas , Humanos , Masculino , Leucemia-Linfoma Linfoblástico de Células T Precursoras/complicações , Leucemia-Linfoma Linfoblástico de Células T Precursoras/psicologia , Resultado do Tratamento , Verduras , Redução de Peso
9.
Clin Nutr ; 35(3): 626-37, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26164552

RESUMO

BACKGROUND & AIMS: Randomised controlled trials (RCTs) in humans revealed contradictory results regarding the effect of vitamin C supplementation on blood lipids. We aimed to conduct a systematic review and meta-analysis of RCTs investigating the effect of vitamin C supplementation on total cholesterol, low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C) and triglycerides and to determine whether the effects are modified by the participants' or intervention characteristics. METHODS: Four databases (PubMed, Embase, Scopus and Cochrane Library) were searched from inception until August 2014 for RCTs supplementing adult participants with vitamin C for ≥ 2 weeks and reporting changes in blood lipids. RESULTS: Overall, vitamin C supplementation did not change blood lipids concentration significantly. However, supplementation reduced total cholesterol in younger participants (≤52 years age) (-0.26 mmol/L, 95% CI: -0.45, -0.07) and LDL-C in healthy participants (-0.32 mmol/L, 95% CI: -0.57, -0.07). In diabetics, vitamin C supplementation reduced triglycerides significantly (-0.15 mmol/L, 95% CI: -0.30, -0.002) and increased HDL-C significantly (0.06 mmol/L, 95% CI: 0.02, 0.11). Meta-regression analyses showed the changes in total cholesterol (ß: -0.24, CI: -0.36, -0.11) and in triglycerides (ß: -0.17, CI: -0.30, -0.05) following vitamin C supplementation were greater in those with higher concentrations of these lipids at baseline. Greater increase in HDL-C was observed in participants with lower baseline plasma concentrations of vitamin C (ß: -0.002, CI: -0.003, -0.0001). CONCLUSIONS: Overall, vitamin C supplementation had no significant effect on lipid profile. However, subgroup and sensitivity analyses showed significant reductions in blood lipids following supplementation in sub-populations with dyslipidaemia or low vitamin C status at baseline. PROSPERO Database registration: CRD42014013487, http://www.crd.york.ac.uk/prospero/.


Assuntos
Antioxidantes/uso terapêutico , Ácido Ascórbico/uso terapêutico , Dislipidemias/dietoterapia , Hipolipemiantes/uso terapêutico , Estresse Oxidativo , Deficiência de Ácido Ascórbico/dietoterapia , Deficiência de Ácido Ascórbico/fisiopatologia , Deficiência de Ácido Ascórbico/prevenção & controle , Fármacos Cardiovasculares/uso terapêutico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Dislipidemias/etiologia , Dislipidemias/fisiopatologia , Dislipidemias/prevenção & controle , Humanos , Hiperlipidemias/dietoterapia , Hiperlipidemias/etiologia , Hiperlipidemias/fisiopatologia , Hiperlipidemias/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , Reprodutibilidade dos Testes , Risco
10.
J Bioeth Inq ; 12(4): 587-99, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26659866

RESUMO

Public health advocates, government agencies, and commercial organizations increasingly use nutritional science to guide food choice and diet as a way of promoting health, preventing disease, or marketing products. We argue that in many instances such references to nutritional science can be characterized as nutritional scientism. We examine three manifestations of nutritional scientism: (1) the simplification of complex science to increase the persuasiveness of dietary guidance, (2) superficial and honorific references to science in order to justify cultural or ideological views about food and health, and (3) the presumption that nutrition is the primary value of food. This paper examines these forms of nutritional scientism in the context of biopolitics to address bioethical concerns related to the misuse of scientific evidence to make claims regarding the effect of diet on health. We argue that nutritional scientism has ethical implications (i) for individual responsibility and freedom, (ii) concerning iatrogenic harm, and (iii) for well-being.


Assuntos
Disciplinas das Ciências Biológicas , Deficiências Nutricionais/dietoterapia , Deficiências Nutricionais/diagnóstico , Dieta , Alimentos , Promoção da Saúde , Política Nutricional , Formulação de Políticas , Saúde Pública , Responsabilidade Social , Ácido Ascórbico/história , Ácido Ascórbico/isolamento & purificação , Deficiência de Ácido Ascórbico/diagnóstico , Deficiência de Ácido Ascórbico/dietoterapia , Liberdade , Saúde , Comportamentos Relacionados com a Saúde , História do Século XIX , História do Século XX , História do Século XXI , Humanos , Doença Iatrogênica , Política Nutricional/história , Política Nutricional/tendências , Saúde Pública/ética , Saúde Pública/métodos , Saúde Pública/normas , Saúde Pública/tendências , Recomendações Nutricionais/história , Recomendações Nutricionais/legislação & jurisprudência , Estados Unidos
11.
Br J Nutr ; 113(4): 603-9, 2015 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-25608928

RESUMO

Vitamin C (VC) is an essential nutrient for humans and certain other animals. It has antioxidant properties and has been reported to ameliorate oxidative damage to lipids, DNA and proteins. However, the effects of VC on immune function are poorly understood, especially the influence of long-term high-dose VC intake on the number and function of immune cells. In the present study, to evaluate the immune effects of VC, VC-deficient senescence marker protein-30 knockout (SMP30KO) mice were fed a diet containing the recommended level of VC (20 mg/kg per d; 0·02 % VC) or a high level of VC (200 mg/kg per d; 0·2 % VC) for 1 year. The plasma VC concentration of the 0·02 % group was the same as that of age-matched C57BL/6 mice after 1 year of feeding; however, plasma VC concentration and thymus weight were significantly higher in the 0·2 % VC group than in the 0·02 % VC group. The total counts of leucocytes, lymphocytes, granulocytes and monocytes in the peripheral blood, as well as the number of splenocytes and thymocytes, were all significantly higher in the 0·2 % VC group than in the 0·02 % VC group. In addition, the number of naive T cells in peripheral blood lymphocytes, the number of memory T-cell populations in splenocytes, and the number of cluster of differentiation (CD)4⁺CD8⁺ or CD4⁺CD8⁻ or CD4⁻CD8⁺ T cells in thymocytes were all markedly higher in the 0·2 % VC group than in the 0·02 % VC group after 1 year of dietary treatment. These results suggest that a long-term high-dose intake of VC is effective in the maintenance of immune cells, partly through the suppression of age-related thymic involution in VC-deficient SMP30KO mice.


Assuntos
Envelhecimento , Ácido Ascórbico/uso terapêutico , Proteínas de Ligação ao Cálcio/metabolismo , Suplementos Nutricionais , Fatores Imunológicos/uso terapêutico , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Doenças Linfáticas/prevenção & controle , Timo/patologia , Animais , Antioxidantes/administração & dosagem , Antioxidantes/efeitos adversos , Antioxidantes/análise , Antioxidantes/uso terapêutico , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/efeitos adversos , Ácido Ascórbico/sangue , Deficiência de Ácido Ascórbico/sangue , Deficiência de Ácido Ascórbico/dietoterapia , Deficiência de Ácido Ascórbico/metabolismo , Deficiência de Ácido Ascórbico/fisiopatologia , Atrofia , Proteínas de Ligação ao Cálcio/genética , Suplementos Nutricionais/efeitos adversos , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/efeitos adversos , Fatores Imunológicos/sangue , Peptídeos e Proteínas de Sinalização Intracelular/genética , Contagem de Leucócitos , Doenças Linfáticas/etiologia , Doenças Linfáticas/imunologia , Doenças Linfáticas/patologia , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Tamanho do Órgão , Distribuição Aleatória , Organismos Livres de Patógenos Específicos , Baço/imunologia , Baço/metabolismo , Baço/patologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/patologia , Timo/imunologia , Timo/metabolismo
12.
Curr Opin Obstet Gynecol ; 26(6): 487-92, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25379767

RESUMO

PURPOSE OF REVIEW: The aim of this review was to evaluate recently published review articles which examine the use of nutritional supplements to prevent preterm birth (PTB) by modifying vaginal bacteria. RECENT FINDINGS: Probiotics, vitamin D and vitamin C were all identified as nutritional supplements that have the potential to alter bacterial flora and consequently reduce PTB and treat or prevent genital infections. Evidence shows that probiotics may reduce the incidence of PTB as well as being effective at treating bacterial vaginosis, a known cause for PTB. Low vitamin D levels may be associated with bacterial vaginosis, although no evidence was identified which demonstrated that vitamin D supplementation reduced the risk of having bacterial vaginosis or PTB.There is little evidence regarding vitamin C supplementation, although it does suggest a possible benefit with regard to preterm rupture of membranes; however, this did not appear to reduce rates of PTB. SUMMARY: Although there is evidence that taking probiotics in pregnancy may reduce the incidence of PTB, it is mainly derived from small, poor quality studies. Vitamin D and vitamin C may have potential benefits, but these remain to be proven. Large randomized controlled trials are needed to more accurately evaluate the potential benefits of these low-cost interventions for reducing PTB and its consequences.


Assuntos
Medicina Baseada em Evidências , Trabalho de Parto Prematuro/prevenção & controle , Fenômenos Fisiológicos da Nutrição Pré-Natal , Probióticos/uso terapêutico , Vagina/microbiologia , Vaginose Bacteriana/prevenção & controle , Ácido Ascórbico/uso terapêutico , Deficiência de Ácido Ascórbico/dietoterapia , Deficiência de Ácido Ascórbico/fisiopatologia , Deficiência de Ácido Ascórbico/prevenção & controle , Suplementos Nutricionais , Feminino , Ruptura Prematura de Membranas Fetais/epidemiologia , Ruptura Prematura de Membranas Fetais/etiologia , Ruptura Prematura de Membranas Fetais/microbiologia , Ruptura Prematura de Membranas Fetais/prevenção & controle , Humanos , Trabalho de Parto Prematuro/epidemiologia , Trabalho de Parto Prematuro/etiologia , Trabalho de Parto Prematuro/microbiologia , Gravidez , Risco , Vaginose Bacteriana/epidemiologia , Vaginose Bacteriana/microbiologia , Vaginose Bacteriana/fisiopatologia , Vitamina D/uso terapêutico , Deficiência de Vitamina D/dietoterapia , Deficiência de Vitamina D/fisiopatologia , Deficiência de Vitamina D/prevenção & controle
14.
J Diet Suppl ; 10(2): 93-104, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23725523

RESUMO

BACKGROUND: Deficient ascorbic acid levels (AALs) and Type 2 diabetes mellitus (T2DM) are associated with periodontal disease. This study evaluated the relationship between plasma AAL and periodontitis in systemically healthy and T2DM subjects, which to the best of our knowledge is being reported for the first time. METHODS: One hundred twenty subjects were categorized into four groups of 30 each as group 1: without periodontal disease; group 2: chronic gingivitis; group 3: chronic periodontitis, and group 4: chronic periodontitis and freshly diagnosed T2DM. Plaque index (PlI), sulcus bleeding index (SBI), and probing pocket depths (PPDs) were evaluated. Venous blood was evaluated for plasma AAL spectrophotometrically. Randomized subjects were subgrouped within groups 2-4, to receive either scaling and root planing (SRP) with dietary supplementation (450 mg) of ascorbic acid (AA) for two weeks or only SRP. After two weeks, the clinical parameters were reassessed. Tukey's multiple post hoc procedures and paired t test were used with the level of statistical significance adjusted to p ≤ .05. RESULTS: AAL plasma levels were significantly greater in group 1 than in group 2 (p = .0007) and in group 4 (p = .0003). A significant reduction in the SBI was seen in the subgroups that received dietary supplementation of vitamin C within group 2 (p = .0012) and group 4 (p = .036). CONCLUSIONS: Plasma AAL is below the normal range in systemically healthy subjects with gingivitis and diabetics with periodontitis. Dietary AA supplementation with SRP improves the SBI in subjects with gingivitis and diabetics with periodontitis.


Assuntos
Deficiência de Ácido Ascórbico/dietoterapia , Ácido Ascórbico/uso terapêutico , Diabetes Mellitus Tipo 2/complicações , Suplementos Nutricionais , Periodontite/terapia , Adulto , Ácido Ascórbico/sangue , Deficiência de Ácido Ascórbico/complicações , Deficiência de Ácido Ascórbico/epidemiologia , Deficiência de Ácido Ascórbico/fisiopatologia , Índice de Placa Dentária , Raspagem Dentária , Método Duplo-Cego , Bolsa Gengival/etiologia , Bolsa Gengival/prevenção & controle , Gengivite/sangue , Gengivite/complicações , Gengivite/etiologia , Gengivite/terapia , Humanos , Índia/epidemiologia , Pessoa de Meia-Idade , Índice Periodontal , Periodontite/sangue , Periodontite/complicações , Periodontite/etiologia , Aplainamento Radicular
15.
Eur J Clin Nutr ; 67(1): 36-41, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23232585

RESUMO

BACKGROUND/OBJECTIVES: A multiple micronutrient-fortified drink could be an effective strategy to combating micronutrient deficiencies in school going children. To assess the efficacy of a multiple micronutrient-fortified drink in reducing iron deficiency (ID), ID anemia (IDA), anemia and improving micronutrient status among schoolchildren with low iron stores. The study employed a school-based, randomized, double-blind, placebo-controlled design. SUBJECTS/METHODS: Schoolchildren with low serum ferritin (SF <20 µg/l) (n=246), aged 6-12 years were randomly assigned to receive either a multi-micronutrient fortified or an unfortified identical control drink. The drinks were provided 6 days/week for 8 weeks. Anthropometric and biochemical assessments were taken at baseline and endline. RESULTS: Study groups at baseline were comparable, and compliance to the intervention was similar. The overall prevalence of ID, IDA and anemia was 64%, 19% and 24%, respectively. The prevalence of ID, IDA, vitamin C and vitamin B12 deficiencies significantly reduced by 42%, 18%, 21% and 5%, respectively, in the intervention arm (P<0.01) as compared with the control arm at the end of the study. Similarly, the concentration of hemoglobin, SF, vitamin A, vitamin B12, vitamin C and body iron stores were significantly higher in the intervention arm in comparison to the control arm (P<0.001). Red cell folate levels also improved significantly in the intervention arm (P=0.04), however, serum zinc status did not change in either of the study arms. Children who had received the fortified drink had significantly lower odds of being ID (0.15; 95% confidence interval (CI): 0.09-0.27), IDA (0.14; 95% CI: 0.04-0.52), vitamin B12 deficient (0.36; 95% CI: 0.18-0.73) and vitamin C deficient (0.24; 95% CI: 0.13-0.46), after adjusting for baseline age, gender and weight. CONCLUSIONS: The multi micronutrient-fortified drink was efficacious in reducing the prevalence of ID, IDA, vitamin C and vitamin B12 deficiency and improved micronutrient status in schoolchildren.


Assuntos
Anemia Ferropriva/dietoterapia , Bebidas/análise , Alimentos Fortificados/análise , Micronutrientes/deficiência , Micronutrientes/uso terapêutico , Estado Nutricional , Anemia Ferropriva/sangue , Anemia Ferropriva/epidemiologia , Anemia Ferropriva/fisiopatologia , Deficiência de Ácido Ascórbico/sangue , Deficiência de Ácido Ascórbico/dietoterapia , Deficiência de Ácido Ascórbico/epidemiologia , Bebidas/efeitos adversos , Criança , Desenvolvimento Infantil , Método Duplo-Cego , Feminino , Serviços de Alimentação , Alimentos Fortificados/efeitos adversos , Humanos , Índia/epidemiologia , Perda de Seguimento , Masculino , Micronutrientes/análise , Micronutrientes/sangue , Cooperação do Paciente , Prevalência , Instituições Acadêmicas , Índice de Gravidade de Doença , Deficiência de Vitamina B 12/sangue , Deficiência de Vitamina B 12/dietoterapia , Deficiência de Vitamina B 12/epidemiologia
16.
J Nutr ; 143(1): 1-11, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23173175

RESUMO

Dietary antioxidants are essential nutrients that inhibit the oxidation of biologically important molecules and suppress the toxicity of reactive oxygen or nitrogen species. When the total antioxidant capacity is insufficient to quench these reactive species, oxidative damage occurs and contributes to the onset and progression of chronic diseases, such as neurodegenerative diseases, cardiovascular diseases, and cancer. However, epidemiological studies that examine the relationship between antioxidants and disease outcome can only identify correlative associations. Additionally, many antioxidants also have prooxidant effects. Thus, clinically relevant animal models of antioxidant function are essential for improving our understanding of the role of antioxidants in the pathogenesis of complex diseases as well as evaluating the therapeutic potential and risks of their supplementation. Recent progress in gene knockout mice and virus-based gene expression has potentiated these areas of study. Here, we review the current genetically modified animal models of dietary antioxidant function and their clinical relevance in chronic diseases. This review focuses on the 3 major antioxidants in the human body: vitamin C, vitamin E, and uric acid. We examine genetic models of vitamin C synthesis (guinea pig, Osteogenic Disorder Shionogi rat, Gulo(-/-) and SMP30(-/-) mouse mutants) and transport (Slc23a1(-/-) and Slc23a2(-/-) mouse mutants), vitamin E transport (Ttpa(-/-) mouse mutant), and uric acid synthesis (Uox(-/-) mouse mutant). The application of these models to current research goals is also discussed.


Assuntos
Antioxidantes/administração & dosagem , Deficiências Nutricionais/fisiopatologia , Modelos Animais de Doenças , Estresse Oxidativo , Animais , Animais Geneticamente Modificados , Antioxidantes/efeitos adversos , Antioxidantes/metabolismo , Antioxidantes/uso terapêutico , Deficiência de Ácido Ascórbico/dietoterapia , Deficiência de Ácido Ascórbico/metabolismo , Deficiência de Ácido Ascórbico/fisiopatologia , Deficiências Nutricionais/dietoterapia , Deficiências Nutricionais/metabolismo , Humanos , Ácido Úrico/administração & dosagem , Ácido Úrico/efeitos adversos , Ácido Úrico/metabolismo , Ácido Úrico/uso terapêutico , Deficiência de Vitamina E/dietoterapia , Deficiência de Vitamina E/metabolismo , Deficiência de Vitamina E/fisiopatologia
17.
Ann Nutr Metab ; 61(3): 259-64, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23183299

RESUMO

The term 'scurvy' for the disease resulting from prolonged vitamin C deficiency had origins in 'scorbutus' (Latin), 'scorbut' (French), and 'Skorbut' (German). Scurvy was a common problem in the world's navies and is estimated to have affected 2 million sailors. In 1747, James Lind conducted a trial of six different treatments for 12 sailors with scurvy: only oranges and lemons were effective in treating scurvy. Scurvy also occurred on land, as many cases occurred with the 'great potato famine' in Ireland in 1845. Many animals, unlike humans, can synthesize their own vitamin C. Axel Holst and Theodor Frölich fortuitously produced scurvy in the guinea pig, which like humans requires vitamin C in the diet. In 1928, Albert Szent-Györgyi isolated a substance from adrenal glands that he called 'hexuronic acid'. Four years later, Charles Glen King isolated vitamin C in his laboratory and concluded that it was the same as 'hexuronic acid'. Norman Haworth deduced the chemical structure of vitamin C in 1933.


Assuntos
Ácido Ascórbico/química , Ácido Ascórbico/história , Ácido Ascórbico/farmacologia , Animais , Deficiência de Ácido Ascórbico/complicações , Deficiência de Ácido Ascórbico/dietoterapia , Deficiência de Ácido Ascórbico/fisiopatologia , Citrus/química , Cobaias , História do Século XVIII , História do Século XIX , História do Século XX , Humanos , Escorbuto/dietoterapia , Escorbuto/etiologia , Escorbuto/fisiopatologia
18.
Rev. esp. nutr. comunitaria ; 16(4): 174-180, oct.-dic. 2010. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-89456

RESUMO

Fundamentos: Evaluar, en mayores de 65 años, institucionalizados, de la ciudad de Lleida (España), el estado nutricional con respecto a vitamina C y retinol. Métodos: Se incluyó a 46 mujeres y 17 varones, residentes permanentes en dos residencias geriátricas de la ciudad de Lleida. Se registraron edad, peso, historia clínica y consumo promedio semanal de alimentos (junio a septiembre). Se determinó, en sangre extraída en ayunas, método habitual de laboratorio, vitamina C (método de Roe) y retinol mediante un micrométodo de HPLC, de fácil realización, que permite efectuar un diagnóstico bioquímico asequible a los laboratorios de mediana complejidad que no dispongan de cromatógrafos de última generación. Resultados: Para los grupos de mujeres y varones, respectivamente, se obtuvo: índice de masa corporal, mediana (intervalo), 23,5 (16,7-35,6) y 24,5 (18,3-36,5). Vitamina C (mg/ dl), 0,879 (0,273-1,592) y 0,884 (0,37-1,398), con adecuación en el 98% de las mujeres y el 100% de los varones. Retinol (μg/dl), 32 (5-117) y 41 (14-61). Los valores de retinol fueron indicativos de deficiencia ( < 20 μg/dl) en el 24,4% de las mujeres y el 13,3% de los varones. Conclusiones: Estos resultados evidencian: a) adecuación nutricional con respecto a vitamina C en la mayoría de los casos, y b) preocupante deficiencia de vitamina A tanto en la población femenina como en la masculina, pese al predominio de sobrepeso. La metodología utilizada permite realizar fácilmente la detección precoz de la deficiencia de vitamina A e implementar estrategias que corrijan los problemas detectados. Se deberá encarar y corregir esta deficiencia mediante intervenciones a corto y mediano plazo, que redundarán en beneficios en la calidad de vida y en los costes de los sistemas de salud(AU)


Objective: To study vitamin A and C status biochemically in individuals aged more than 65 years old, living in two institutions in Lleida (Spain). Methods: Forty-six women and 17 men, living permanently in two institutions in Lleida city were studied. Age, weight, clinical history, and mean weekly food consumption (between June and September) were recorded. Fasting serum was extracted to determine vitamin C (Roe method) and vitamin A levels, though an easy-to-perform high-performance liquid chromatography (HPLC) micromethod that allows a biochemical diagnosis to be made in medium-complexity laboratories without state-of-the art chromatographic methods. Results. The results (median and ranges) in women and men, respectively, were as follows: BMI (Kg/m2) 23.5 (16.7—35.6) and 24.5 (18.3-36.5); vitamin C (mg/dL): 0.879 (0.273-1.592) and 0.884 (0.370-1.398), with adequate status in 98% of the women and in 100 % of the men; retinol (μg/dL): 32 (5-117) and 41 (14-61), presenting deficiency ... (AU)


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Ácido Ascórbico/análise , Saúde do Idoso Institucionalizado , Índice de Massa Corporal , Sobrepeso/dietoterapia , Qualidade de Vida , Deficiência de Ácido Ascórbico/dietoterapia , Deficiência de Vitamina A/dietoterapia , Avaliação Nutricional , Estado Nutricional/fisiologia , Carotenoides/análise , Cromatografia , Estilo de Vida , Ácido Ascórbico/sangue , Protocolos Clínicos , 28599
19.
Int J Rheum Dis ; 12(4): 361-5, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20374377

RESUMO

We report three cases of scurvy, with differing musculoskeletal presentations, from a tertiary teaching hospital in Sydney, Australia. Case 1 was a man with cerebral palsy who presented with knee swelling following a minor injury. In Case 2, a patient with thalassaemia major presented with purpuric rash, difficulty walking and distal thigh swelling and ecchymosis. Case 3 was a man with Down's syndrome who presented with acute ankle arthritis. Scurvy in Cases 1 and 3 were related to abnormal dietary preferences, whereas in Case 2, scurvy was thought to be related to thalassaemia. All three cases responded rapidly to vitamin C replacement. The subjects did not appear malnourished as they had adequate carbohydrate and protein intake.


Assuntos
Escorbuto/diagnóstico , Adulto , Ácido Ascórbico/administração & dosagem , Deficiência de Ácido Ascórbico/complicações , Deficiência de Ácido Ascórbico/diagnóstico , Deficiência de Ácido Ascórbico/dietoterapia , Paralisia Cerebral/complicações , Paralisia Cerebral/dietoterapia , Paralisia Cerebral/patologia , Síndrome de Down/complicações , Síndrome de Down/patologia , Comportamento Alimentar , Hospitais de Ensino , Humanos , Masculino , Escorbuto/complicações , Escorbuto/dietoterapia , Resultado do Tratamento , Talassemia beta/complicações , Talassemia beta/dietoterapia , Talassemia beta/patologia
20.
Med Hypotheses ; 62(4): 533-6, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15050101

RESUMO

The findings of subdural hematoma and retinal hemorrhages in infants, without any documented history of major trauma, do not always indicate child abuse. A combination of ascorbate depletion and the injection of foreign proteins can cause a very high blood histamine level, leading to capillary fragility and venular bleeding. This can be prevented by the administration of vitamin C.


Assuntos
Deficiência de Ácido Ascórbico/sangue , Histamina/sangue , Síndrome do Bebê Sacudido/prevenção & controle , Vacinação/efeitos adversos , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/sangue , Deficiência de Ácido Ascórbico/dietoterapia , Deficiência de Ácido Ascórbico/patologia , Fragilidade Capilar , Hematoma Subdural/etiologia , Humanos , Recém-Nascido , Hemorragia Retiniana/etiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...