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2.
Nutrients ; 12(8)2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32751086

RESUMO

Recent research studies have shown that vitamin C (ascorbic acid) may affect bone mineral density and that a deficiency of ascorbic acid leads to the development of osteoporosis. Patients suffering from an inflammatory bowel disease are at a risk of low bone mineral density. It is vital to notice that patients with Crohn's disease and ulcerative colitis also are at risk of vitamin C deficiency which is due to factors such as reduced consumption of fresh vegetables and fruits, i.e., the main sources of ascorbic acid. Additionally, some patients follow diets which may provide an insufficient amount of vitamin C. Moreover, serum vitamin C level also is dependent on genetic factors, such as SLC23A1 and SLC23A2 genes, encoding sodium-dependent vitamin C transporters and GSTM1, GSTP1 and GSTT1 genes which encode glutathione S-transferases. Furthermore, ascorbic acid may modify the composition of gut microbiota which plays a role in the pathogenesis of an inflammatory bowel disease.


Assuntos
Deficiência de Ácido Ascórbico/sangue , Ácido Ascórbico/sangue , Doenças Inflamatórias Intestinais/sangue , Osteoporose/etiologia , Deficiência de Ácido Ascórbico/etiologia , Deficiência de Ácido Ascórbico/genética , Densidade Óssea , Colite Ulcerativa/sangue , Colite Ulcerativa/complicações , Colite Ulcerativa/genética , Doença de Crohn/sangue , Doença de Crohn/complicações , Doença de Crohn/genética , Dieta/efeitos adversos , Feminino , Microbioma Gastrointestinal/fisiologia , Glutationa S-Transferase pi/sangue , Glutationa Transferase/sangue , Humanos , Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/genética , Masculino , Osteoporose/genética , Fatores de Risco , Transportadores de Sódio Acoplados à Vitamina C/sangue
3.
Nutrients ; 12(6)2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32599718

RESUMO

Patients undergoing myeloablative chemotherapy and hematopoietic stem cell transplantation (HSCT) experience profound neutropenia and vulnerability to infection. Previous research has indicated that patients with infections have depleted vitamin C status. In this study, we recruited 38 patients with hematopoietic cancer who were undergoing conditioning chemotherapy and HSCT. Blood samples were collected prior to transplantation, at one week, two weeks and four weeks following transplantation. Vitamin C status and biomarkers of inflammation (C-reactive protein) and oxidative stress (protein carbonyls and thiobarbituric acid reactive substances) were assessed in association with febrile neutropenia. The vitamin C status of the study participants decreased from 44 ± 7 µmol/L to 29 ± 5 µmol/L by week one (p = 0.001) and 19 ± 6 µmol/L by week two (p < 0.001), by which time all of the participants had undergone a febrile episode. By week four, vitamin C status had increased to 37 ± 10 µmol/L (p = 0.1). Pre-transplantation, the cohort comprised 19% with hypovitaminosis C (i.e., <23 µmol/L) and 8% with deficiency (i.e., <11 µmol/L). At week one, those with hypovitaminosis C had increased to 38%, and at week two, 72% had hypovitaminosis C, and 34% had outright deficiency. C-reactive protein concentrations increased from 3.5 ± 1.8 mg/L to 20 ± 11 mg/L at week one (p = 0.002), and 119 ± 25 mg/L at week two (p < 0.001), corresponding to the development of febrile neutropenia in the patients. By week four, these values had dropped to 17 ± 8 mg/L (p < 0.001). There was a significant inverse correlation between C-reactive protein concentrations and vitamin C status (r = -0.424, p < 0.001). Lipid oxidation (thiobarbituric acid reactive substances (TBARS)) increased significantly from 2.0 ± 0.3 µmol/L at baseline to 3.3 ± 0.6 µmol/L by week one (p < 0.001), and remained elevated at week two (p = 0.003), returning to baseline concentrations by week four (p = 0.3). Overall, the lowest mean vitamin C values (recorded at week two) corresponded with the highest mean C-reactive protein values and lowest mean neutrophil counts. Thus, depleted vitamin C status in the HSCT patients coincides with febrile neutropenia and elevated inflammation and oxidative stress.


Assuntos
Deficiência de Ácido Ascórbico , Ácido Ascórbico/sangue , Neutropenia Febril Induzida por Quimioterapia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Agonistas Mieloablativos , Idoso , Deficiência de Ácido Ascórbico/complicações , Deficiência de Ácido Ascórbico/etiologia , Neutropenia Febril Induzida por Quimioterapia/complicações , Neutropenia Febril Induzida por Quimioterapia/etiologia , Feminino , Neoplasias Hematológicas/terapia , Humanos , Hospedeiro Imunocomprometido , Inflamação , Masculino , Pessoa de Meia-Idade , Agonistas Mieloablativos/efeitos adversos , Agonistas Mieloablativos/uso terapêutico , Estresse Oxidativo/fisiologia
4.
Nutrients ; 12(6)2020 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-32503297

RESUMO

To date, there are no recommendations about screening plasma vitamin C concentration and adjust its supplementation in patients on long-term home parenteral nutrition (HPN). The aim of this study was to evaluate vitamin C status and determine if a commercial multivitamin preparation (CMVP) containing 125 mg of vitamin C is sufficient in stable patients on HPN. All clinically stable patients receiving HPN or an intravenous fluid infusion at least two times per week for at least 6 months, hospitalized for nutritional assessment, were retrospectively included, for a total of 186 patients. We found that 29% of the patients had vitamin C insufficiency (i.e., <25 µmol/L). In univariate analysis, C-reactive protein (CRP) (p = 0.002) and intake of only 125 mg of vitamin C (p = 0.001) were negatively associated with vitamin C levels, and duration of follow-up in our referral center (p = 0.009) was positively associated with vitamin C levels. In multivariate analysis, only CRP (p = 0.001) and intake of 125 mg of vitamin C (p < 0.0001) were independently associated with low plasma vitamin C concentration. Patients receiving only CMVP with a low plasma vitamin C level significantly received personal compounded HPN (p = 0.008) and presented an inflammatory syndrome (p = 0.002). Vitamin C insufficiency is frequent in individuals undergoing home parenteral nutrition; therefore, there is a need to monitor plasma vitamin C levels, especially in patients on HPN with an inflammatory syndrome and only on CMVP.


Assuntos
Deficiência de Ácido Ascórbico/etiologia , Deficiência de Ácido Ascórbico/prevenção & controle , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/sangue , Ingestão de Alimentos/fisiologia , Monitorização Fisiológica , Avaliação Nutricional , Fenômenos Fisiológicos da Nutrição/fisiologia , Estado Nutricional , Nutrição Parenteral Total no Domicílio , Adulto , Idoso , Ácido Ascórbico/análise , Deficiência de Ácido Ascórbico/sangue , Deficiência de Ácido Ascórbico/diagnóstico , Biomarcadores/sangue , Feminino , Humanos , Inflamação/etiologia , Masculino , Pessoa de Meia-Idade , Nutrição Parenteral Total no Domicílio/efeitos adversos , Estudos Retrospectivos
5.
Nutrients ; 12(5)2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32384616

RESUMO

Pneumonia is a severe lower respiratory tract infection that is a common complication and a major cause of mortality of the vitamin C-deficiency disease scurvy. This suggests an important link between vitamin C status and lower respiratory tract infections. Due to the paucity of information on the vitamin C status of patients with pneumonia, we assessed the vitamin C status of 50 patients with community-acquired pneumonia and compared these with 50 healthy community controls. The pneumonia cohort comprised 44 patients recruited through the Acute Medical Assessment Unit (AMAU) and 6 patients recruited through the Intensive Care Unit (ICU); mean age 68 ± 17 years, 54% male. Clinical, microbiological and hematological parameters were recorded. Blood samples were tested for vitamin C status using HPLC with electrochemical detection and protein carbonyl concentrations, an established marker of oxidative stress, using ELISA. Patients with pneumonia had depleted vitamin C status compared with healthy controls (23 ± 14 µmol/L vs. 56 ± 24 µmol/L, p < 0.001). The more severe patients in the ICU had significantly lower vitamin C status than those recruited through AMAU (11 ± 3 µmol/L vs. 24 ± 14 µmol/L, p = 0.02). The pneumonia cohort comprised 62% with hypovitaminosis C and 22% with deficiency, compared with only 8% hypovitaminosis C and no cases of deficiency in the healthy controls. The pneumonia cohort also exhibited significantly elevated protein carbonyl concentrations compared with the healthy controls (p < 0.001), indicating enhanced oxidative stress in the patients. We were able to collect subsequent samples from 28% of the cohort (mean 2.7 ± 1.7 days; range 1-7 days). These showed no significant differences in vitamin C status or protein carbonyl concentrations compared with baseline values (p = 0.6). Overall, the depleted vitamin C status and elevated oxidative stress observed in the patients with pneumonia indicates an enhanced requirement for the vitamin during their illness. Therefore, these patients would likely benefit from additional vitamin C supplementation to restore their blood and tissue levels to optimal. This may decrease excessive oxidative stress and aid in their recovery.


Assuntos
Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/metabolismo , Infecções Comunitárias Adquiridas/metabolismo , Infecções Comunitárias Adquiridas/terapia , Suplementos Nutricionais , Estresse Oxidativo , Pneumonia/metabolismo , Pneumonia/terapia , Idoso , Idoso de 80 Anos ou mais , Ácido Ascórbico/sangue , Ácido Ascórbico/farmacologia , Deficiência de Ácido Ascórbico/etiologia , Deficiência de Ácido Ascórbico/metabolismo , Deficiência de Ácido Ascórbico/terapia , Estudos de Coortes , Infecções Comunitárias Adquiridas/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo/efeitos dos fármacos , Pneumonia/complicações , Carbonilação Proteica
6.
Crit Care ; 23(1): 165, 2019 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-31077227

RESUMO

BACKGROUND: At least a third of the world's population consumes alcohol regularly. Patients with alcohol use disorders (AUDs) are frequently hospitalized for both alcohol-related and unrelated medical conditions. It is well recognized that patients with an AUD are thiamine deficient with thiamine replacement therapy being considered the standard of care. However, the incidence of vitamin C deficiency in this patient population has been poorly defined. METHODS: In this retrospective, observational study, we recorded the admission vitamin C level in patients with an AUD admitted to our medical intensive care unit (MICU) over a 1-year period. In addition, we recorded relevant clinical and laboratory data including the day 2 and day 3 vitamin C level following empiric treatment with vitamin C. Septic patients were excluded from this study. RESULTS: Sixty-nine patients met the inclusion criteria for this study. The patients' mean age was 53 ± 14 years; 52 patients (75%) were males. Severe alcohol withdrawal syndrome was the commonest admitting diagnosis (46%). Eighteen patients (26%) had cirrhosis as the admitting diagnosis with 18 (13%) patients admitted due to alcohol/drug intoxication. Forty-six patients (67%) had evidence of acute alcoholic hepatitis. The mean admission vitamin C level was 17.0 ± 18.1 µmol/l (normal 40-60 µmol/l). Sixty-one (88%) patients had a level less than 40 µmol/l (subnormal) while 52 patients (75%) had hypovitaminosis C (level < 23 µmol/l). None of the variables recorded predicted the vitamin C level. Various vitamin C replacement dosing strategies were used. A 1.5-g loading dose, followed by 500-mg PO q 6, was effective in restoring blood levels to normal by day 2. CONCLUSION: Our results suggest that hypovitaminosis C is exceedingly common in patients with an AUD admitted to an intensive care unit and that all such patients should receive supplementation with vitamin C in addition to thiamine. Additional studies are required to confirm the findings of our observational study and to determine the optimal vitamin C dosing strategy.


Assuntos
Alcoolismo/complicações , Deficiência de Ácido Ascórbico/etiologia , Adulto , Idoso , Alcoolismo/epidemiologia , Deficiência de Ácido Ascórbico/epidemiologia , Citrus sinensis/metabolismo , Suplementos Nutricionais , Feminino , Humanos , Unidades de Terapia Intensiva/organização & administração , Unidades de Terapia Intensiva/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Musa/metabolismo , Estudos Retrospectivos , Escorbuto/tratamento farmacológico , Escorbuto/prevenção & controle , Virginia/epidemiologia
7.
Nutrition ; 60: 185-190, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30612038

RESUMO

Vitamin C exhibits interesting properties in the context of critical illness, with benefits described in neurologic, cardiovascular, renal, and hematologic systems, both in in vitro and in animal models. Through direct effects on bacterial replication, immunomodulation, and antioxidant reserve of the organism, vitamin C directly affects the pathophysiological process of sepsis, trauma, burn, and systemic inflammation. Even if several observational trials have linked vitamin C deficiency to worse outcomes, the evidence is not such as to provide us with a distinction between causality effects or simple epiphenomenon, and the current focus is on interventional trials. Pharmacokinetic data suggest that a minimal supplementation of 3 g/d intravenously is required to restore normal serum values in critically ill patients with known deficiency. According to these data, only five trials, including a retrospective analysis, studied pharmacologic dose: three as an antioxidant cocktail and two as monotherapy. The largest trial, conducted in 2002, reported reduced incidence of multiorgan failure and duration of mechanical ventilation. Recently a retrospective analysis reported impressive results after administration of vitamin C, thiamine, and hydrocortisone. The two most recent trials reported improved clinical outcomes, including improved mortality, but contained significant methodological limitations. A recent systematic review did not find clinical benefits with the most-studied low-dose oral supplementation, potentially because of suboptimal or insufficient repletion. Current guidelines do not support the administration of high-dose vitamin C in critically ill patients. Future larger trials are required to support any therapy, but the low cost and safety profile can justify supplementation in the meantime. Metabolomics study will further help understand biological effect.


Assuntos
Deficiência de Ácido Ascórbico/terapia , Ácido Ascórbico/administração & dosagem , Estado Terminal/terapia , Suplementos Nutricionais , Vitaminas/administração & dosagem , Administração Intravenosa , Deficiência de Ácido Ascórbico/etiologia , Humanos , Índice de Gravidade de Doença , Resultado do Tratamento
9.
Int J Psychiatry Med ; 54(1): 64-73, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30079810

RESUMO

BACKGROUND: Autism spectrum disorder is a heterogenous neurodevelopmental condition accompanied by a variety of associated features. Case reports suggest one such associated feature, food selectivity, increases risk for nutritional deficiencies; however, little attention has been given to prevent and treat nutritional deficiencies in youth with autism spectrum disorder. METHOD: Single case report. RESULTS: This single case report presents a child with autism spectrum disorder and food selectivity difficulties that resulted in severe vitamin C deficiency. Although eventually corrected, the nutritional deficiency was debilitating, required invasive interventions, and resulted in significant social/emotional and economic costs. CONCLUSIONS: We review the course of treatment and highlight strategies to prevent and more effectively treat nutritional deficiencies in youth with autism spectrum disorder.


Assuntos
Deficiência de Ácido Ascórbico , Ácido Ascórbico/administração & dosagem , Transtorno do Espectro Autista , Preferências Alimentares/psicologia , Desnutrição , Adolescente , Deficiência de Ácido Ascórbico/etiologia , Deficiência de Ácido Ascórbico/fisiopatologia , Deficiência de Ácido Ascórbico/psicologia , Deficiência de Ácido Ascórbico/terapia , Transtorno do Espectro Autista/complicações , Transtorno do Espectro Autista/fisiopatologia , Transtorno do Espectro Autista/psicologia , Dietoterapia/métodos , Diagnóstico Precoce , Humanos , Masculino , Desnutrição/etiologia , Desnutrição/psicologia , Desnutrição/terapia , Administração dos Cuidados ao Paciente/métodos , Medição de Risco , Vitaminas/administração & dosagem
10.
Crit Care ; 22(1): 70, 2018 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-29558975

RESUMO

This article is one of ten reviews selected from the Annual Update in Intensive Care and Emergency Medicine 2018. Other selected articles can be found online at https://www.biomedcentral.com/collections/annualupdate2018 . Further information about the Annual Update in Intensive Care and Emergency Medicine is available from http://www.springer.com/series/8901 .


Assuntos
Ácido Ascórbico/farmacocinética , Traumatismo por Reperfusão/tratamento farmacológico , Fatores de Tempo , Síndrome Coronariana Aguda/complicações , Síndrome Coronariana Aguda/tratamento farmacológico , Administração Intravenosa , Ácido Ascórbico/uso terapêutico , Deficiência de Ácido Ascórbico/tratamento farmacológico , Deficiência de Ácido Ascórbico/etiologia , Humanos , Traumatismo por Reperfusão/fisiopatologia , Traumatismo por Reperfusão/prevenção & controle , Vitaminas/farmacocinética , Vitaminas/uso terapêutico
11.
Adv Clin Exp Med ; 26(4): 581-586, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28691410

RESUMO

BACKGROUND: The increasing incidence of metabolic diseases such as obesity or diabetes have made them a major public health problem. Increasing oxidative stress induced by reactive oxygen species, which initiate the oxidative adverse changes in the cell, is mentioned, among other risk factors, to underlie these diseases. Vitamin A, C and E are listed among the non-enzymatic mechanisms counteracting this phenomenon. Vitamin D deficiency is also associated with cardiovascular diseases. OBJECTIVES: The aim of the study was to assess the risk of vitamin A, C, E and D deficit in the plasma of metabolic syndrome (MS) patients. MATERIAL AND METHODS: The study included 191 patients with MS and 98 subjects without MS. Loglinear analysis was used in the assessment of mutual interactions between the vitamin concentration and the analysis of classification by ROC curves to predict the frequency of vitamin deficiency in MS patients. RESULTS: A correlation was found between the plasma level of vitamins in the group of MS patients. Vitamin A concentration correlated with that of vitamin C (r = 0.51, p = 0.0000), vitamin D (r = 0.49, p = 0.0000) and E (r = 0.32, p = 0.0001). The plasma level of vitamin D correlated with the level of vitamin E (r = 0.46, p = 0.00000) and vitamin C (r = 0.37, p = 0.0000). Regression analysis showed a correlation between the concentration of the tested vitamins in patients with MS. Interactions were observed between vitamins C and A and between C and D. HDL cholesterol level was lower in patients with vitamin A deficiency compared to patients with its normal level. CONCLUSIONS: The plasma levels of vitamin A, C, E and D were significantly lower in patients with MS than in healthy subjects and they mutually correlated with each other. The normalization of glucose and HDL level may contribute to the regulation of the concentration of vitamin A in patients with MS.


Assuntos
Deficiência de Ácido Ascórbico/etiologia , Síndrome Metabólica/complicações , Deficiência de Vitamina A/etiologia , Deficiência de Vitamina D/etiologia , Deficiência de Vitamina E/etiologia , Adulto , Idoso , Ácido Ascórbico/sangue , Estudos de Casos e Controles , HDL-Colesterol/sangue , Feminino , Humanos , Masculino , Síndrome Metabólica/sangue , Pessoa de Meia-Idade , Espécies Reativas de Oxigênio/metabolismo , Risco , Vitamina A/sangue , Vitamina D/sangue , Vitamina E/sangue
12.
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
13.
J Health Popul Nutr ; 35: 11, 2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-27093922

RESUMO

BACKGROUND: Among the studies published after the year 2000 which focused on nutrition at preschool, only three aimed to assess children's intake of energy and selected nutrients at preschool. The purpose of this study was to assess dietary intake in children during their stay at preschool. METHODS: The studied population comprised 128 4-6-year-old children who attended preschools in Pila, Poland. Intakes of energy and macronutrients were estimated from a 5-day weighed food record completed by the preschool staff. Weight and height were measured, and BMI was calculated. Statistical analysis was carried out using the IBM SPSS Statistics 21.0 computer programme. The data were analysed according to gender. RESULTS: Energy intake was the lowest in children with underweight, 2004 kJ (478 kcal), and the highest in obese children, 3388 kJ (809 kcal). Energy intake from lactose was statistically significantly higher in boys than in girls, 3.0 vs 2.6 %. Statistically significantly higher percentage of boys in comparison to girls had intakes of vitamin C below 70 % of EAR, 56.9 vs 38.1 %. It is important to highlight the excessive intake of energy from saturated fatty acids and energy from sucrose, along with inadequate intake of energy from polyunsaturated fatty acids. We also found excessive intake of sodium and inadequate intakes of dietary fibre, water, vitamin D, vitamin E, folate, niacin, calcium and potassium. CONCLUSIONS: Preschool diets need urgent improvement to prevent diet-related diseases in the studied preschoolers in the future. The inadequacies observed in these diets are in accordance with the previously reported inadequacies in menus planned for preschoolers. More research is needed to investigate dietary intake of children during their stay at preschool. Common regulations worked out for all preschools in the European Union would be a good way to provide adequate nutrition to preschool children.


Assuntos
Fenômenos Fisiológicos da Nutrição Infantil , Deficiências Nutricionais/etiologia , Dieta/efeitos adversos , Serviços de Alimentação , Obesidade Pediátrica/etiologia , Escolas Maternais , Magreza/etiologia , Deficiência de Ácido Ascórbico/epidemiologia , Deficiência de Ácido Ascórbico/etiologia , Índice de Massa Corporal , Criança , Fenômenos Fisiológicos da Nutrição Infantil/etnologia , Pré-Escolar , Deficiências Nutricionais/epidemiologia , Dieta/etnologia , Registros de Dieta , Ingestão de Energia , Feminino , Humanos , Masculino , Obesidade Pediátrica/epidemiologia , Polônia/epidemiologia , Prevalência , Fatores de Risco , Fatores Sexuais , Magreza/epidemiologia
14.
Muscle Nerve ; 54(6): 1120-1132, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27074419

RESUMO

INTRODUCTION: There is evidence that supports a role for Vitamin D (Vit. D) in muscle. The exact mechanism by which Vit. D deficiency impairs muscle strength and function is not clear. METHODS: Three-week-old mice were fed diets with varied combinations of Vit. D and Ca2+ deficiency. Behavioral testing, genomic and protein analysis, and muscle histology were performed with a focus on neuromuscular junction (NMJ) -related genes. RESULTS: Vit. D and Ca2+ deficient mice performed more poorly on given behavioral tasks than animals with Vit. D deficiency alone. Genomic and protein analysis of the soleus and tibialis anterior muscles revealed changes in several Vit. D metabolic, NMJ-related, and protein chaperoning and refolding genes. CONCLUSIONS: These data suggest that detrimental effects of a Vit. D deficient or a Vit. D and Ca2+ deficient diet may be a result of differential alterations in the structure and function of the NMJ and a lack of a sustained stress response in muscles. Muscle Nerve 54: 1120-1132, 2016.


Assuntos
Deficiência de Ácido Ascórbico/patologia , Dieta/efeitos adversos , Regulação da Expressão Gênica/fisiologia , Membro Posterior/patologia , Fibras Musculares Esqueléticas/fisiologia , Junção Neuromuscular/fisiopatologia , Fatores Etários , Animais , Deficiência de Ácido Ascórbico/sangue , Deficiência de Ácido Ascórbico/etiologia , Deficiência de Ácido Ascórbico/metabolismo , Cálcio/metabolismo , Modelos Animais de Doenças , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Locomoção , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Força Muscular , Hormônio Paratireóideo/sangue , Fósforo/sangue , Equilíbrio Postural , Desempenho Psicomotor , Vitamina D/metabolismo
15.
BMJ Case Rep ; 20162016 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-26994047

RESUMO

In Switzerland, vitamin C deficiency is a rare condition. Nonetheless, in clinical practice, there are some patients exhibiting a vitamin C deficiency as a result of an unbalanced diet or intestinal malabsorption. We report the clinical history of a 55-year-old man known for alcoholism and insufficient intake of fresh fruits and vegetables. He was admitted to the intensive care unit, for haemodynamic instability caused by blood loss due to fragile vessels (skin, gastrointestinal). Further analyses revealed a severe lack of vitamin C. The patient received a high dose of intravenous substitutive treatment, leading to a favourable clinical outcome.


Assuntos
Alcoolismo/complicações , Deficiência de Ácido Ascórbico/etiologia , Desnutrição/complicações , Púrpura/etiologia , Anemia/etiologia , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/sangue , Deficiência de Ácido Ascórbico/diagnóstico , Dieta , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Suíça
16.
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
17.
Eur J Haematol ; 96(3): 318-26, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26018112

RESUMO

BACKGROUND: Vitamin C, as antioxidant, increases the efficacy of deferoxamine (DFO). AIM: To investigate the effects of vitamin C as an adjuvant therapy to the three used iron chelators in moderately iron-overloaded young vitamin C-deficient patients with ß-thalassemia major (ß-TM) in relation to tissue iron overload. METHODS: This randomized prospective trial that included 180 ß-TM vitamin C-deficient patients were equally divided into three groups (n = 60) and received DFO, deferiprone (DFP), and deferasirox (DFX). Patients in each group were further randomized either to receive vitamin C supplementation (100 mg daily) or not (n = 30). All patients received vitamin C (group A) or no vitamin C (group B) were followed up for 1 yr with assessment of transfusion index, hemoglobin, iron profile, liver iron concentration (LIC) and cardiac magnetic resonance imaging (MRI) T2*. RESULTS: Baseline vitamin C was negatively correlated with transfusion index, serum ferritin (SF), and LIC. After vitamin C therapy, transfusion index, serum iron, SF, transferrin saturation (Tsat), and LIC were significantly decreased in group A patients, while hemoglobin and cardiac MRI T2* were elevated compared with baseline levels or those in group B without vitamin C. The same improvement was found among DFO-treated patients post-vitamin C compared with baseline data. DFO-treated patients had the highest hemoglobin with the lowest iron, SF, and Tsat compared with DFP or DFX subgroups. CONCLUSIONS: Vitamin C as an adjuvant therapy possibly potentiates the efficacy of DFO more than DFP and DFX in reducing iron burden in the moderately iron-overloaded vitamin C-deficient patients with ß-TM, with no adverse events.


Assuntos
Ácido Ascórbico/uso terapêutico , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Talassemia beta/complicações , Ácido Ascórbico/administração & dosagem , Deficiência de Ácido Ascórbico/tratamento farmacológico , Deficiência de Ácido Ascórbico/etiologia , Biomarcadores , Suplementos Nutricionais , Quimioterapia Combinada , Feminino , Humanos , Ferro/metabolismo , Quelantes de Ferro/administração & dosagem , Sobrecarga de Ferro/diagnóstico , Fígado/metabolismo , Fígado/patologia , Imageamento por Ressonância Magnética , Masculino , Resultado do Tratamento , Talassemia beta/terapia
18.
Am J Clin Nutr ; 102(6): 1416-24, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26537939

RESUMO

BACKGROUND: Vitamin C sufficiency may help prevent osteoporosis and fractures by mediating osteoclastogenesis, osteoblastogenesis, and bone collagen synthesis. OBJECTIVE: We determined whether dietary intakes and plasma concentrations of vitamin C were associated with a heel ultrasound and hip and spine fracture risks in older men and women. DESIGN: Participants were recruited from the European Prospective Investigation into Cancer in Norfolk study with 7-d diet diary estimates of vitamin C intake and plasma concentrations. A random subset (4000 of 25,639 subjects) was available for the cross-sectional (ultrasound) study of broadband ultrasound attenuation (BUA) and velocity of sound (VOS), which were determined during the second health examination. The prospective (fracture) study was a case-cohort sample of all participants with a fracture up to March 2009 and the random subset (n = 5319). ANCOVA-determined associations between quintiles of vitamin C intake and plasma status with adjusted BUA and VOS and adjusted Prentice-weighted Cox proportional HRs were calculated for fracture risk. RESULTS: Women were 58% of the population (39-79 y old), and the median follow-up was 12.6 y (range: 0-16 y). Positive associations across all quintiles of vitamin C intake but not plasma status were significant for VOS in men (ß = 2.47 m/s, P = 0.008) and BUA in women (ß = 0.82 dB/MHz, P = 0.004). Vitamin C intake was not associated with fracture risk, but there was an inverse association with plasma concentrations in men, with quintile 4 having significantly lower risks of hip fractures (HR: 0.35; 95% CI: 0.16, 0.80) and spine fractures (HR: 0.26; 95% CI: 0.10, 0.69) than quintile 1. CONCLUSIONS: Higher vitamin C intake was significantly associated with higher heel ultrasound measures in men and women, and higher plasma vitamin C concentrations were significantly associated with reduced fracture risk in men only. Our findings that vitamin C intake and status were inconsistently associated with bone health variables suggest that additional research is warranted.


Assuntos
Deficiência de Ácido Ascórbico/fisiopatologia , Ácido Ascórbico/sangue , Dieta/efeitos adversos , Fraturas do Quadril/etiologia , Osteoporose/etiologia , Fraturas por Osteoporose/etiologia , Fraturas da Coluna Vertebral/etiologia , Adulto , Idoso , Ácido Ascórbico/uso terapêutico , Deficiência de Ácido Ascórbico/etiologia , Deficiência de Ácido Ascórbico/prevenção & controle , Densidade Óssea , Estudos de Casos e Controles , Estudos de Coortes , Estudos Transversais , Registros de Dieta , Inglaterra/epidemiologia , Feminino , Fraturas do Quadril/epidemiologia , Fraturas do Quadril/prevenção & controle , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Osteoporose/sangue , Osteoporose/fisiopatologia , Osteoporose/prevenção & controle , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/prevenção & controle , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco , Fraturas da Coluna Vertebral/epidemiologia , Fraturas da Coluna Vertebral/prevenção & controle
19.
Br J Nutr ; 113(5): 859-64, 2015 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-25735881

RESUMO

Women show higher vitamin C plasma concentrations than men, but the reasons for this observation still require elucidation. The objective of the present study was to investigate whether sex differences in vitamin C plasma concentrations are present in elderly subjects and whether these differences are due to sex-specific lifestyles, total antioxidant status (TAOS) and/or body composition. Fasting plasma concentrations of vitamin C were assessed by photometric detection in a cross-sectional study of 181 women and eighty-nine men aged 62-92 years. Body composition was determined by bioelectrical impedance analysis. Vitamin C intake was assessed with a 3 d estimated dietary record. Stepwise multiple regression analyses were performed to investigate whether sex is an independent predictor of vitamin C plasma concentrations by controlling for age, vitamin C intake, lifestyle factors, TAOS and body composition. Women showed higher vitamin C plasma concentrations than men (76 v. 62 µmol/l, P< 0·0001). In the multiple regression analysis, male sex was a negative predictor of vitamin C plasma concentrations (ß = -0·214), as long as absolute fat-free mass (FFM) was not considered as a confounder. When absolute FFM was included, sex was no longer a predictor of vitamin C plasma concentrations, whereas absolute FFM (ß = -0·216), physical activity level (ß = 0·165), intake of vitamin C supplements (ß = 0·164), age (ß = 0·147) and smoking (ß = -0·125) affected vitamin C plasma concentrations. The results indicate that a higher absolute FFM, and thus a higher distribution volume of vitamin C, contributes to lower vitamin C plasma concentrations in men than women.


Assuntos
Envelhecimento , Deficiência de Ácido Ascórbico/epidemiologia , Ácido Ascórbico/sangue , Regulação para Baixo , Idoso , Idoso de 80 Anos ou mais , Ácido Ascórbico/uso terapêutico , Deficiência de Ácido Ascórbico/sangue , Deficiência de Ácido Ascórbico/etiologia , Deficiência de Ácido Ascórbico/prevenção & controle , Constituição Corporal , Estudos de Coortes , Estudos Transversais , Suplementos Nutricionais , Feminino , Alemanha/epidemiologia , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Atividade Motora , Prevalência , Reprodutibilidade dos Testes , Fatores Sexuais , Fumar/efeitos adversos
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