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1.
An early diagnosis of nutrition deficiency and metabolic disorders in autism and proper therapeutic interventions in some patients significantly improve both cognitive abilities and behavioral deficiencies. Some authors suggested that support for the nutritional and metabolic problems by increasing nutrient intake may reduce the symptoms and co-morbidities that are associated with autism. In this respect, the nutritional intervention and proper supplementation plays a more and more important role in the treatment of autism. In this paper we summarize current knowledge about importance of metabolic factors in autistic spectrum disorders and present influence of suitable and personalized diet on symptoms of this disorder.  相似文献   

2.
Cell-mediated immunity in nutritional deficiency   总被引:7,自引:0,他引:7  
Dietary deficiencies of specific nutrients profoundly alter cell-mediated immune responses in man and experimental animals. Both moderate and severe deficiencies are associated with significant changes in immunocompetence. Diets with inadequate levels of protein, calories, vitamin A, pyridoxine, biotin and zinc result in loss of thymic cellularity. Secondary to thymic atrophy, the production of thymic hormones critical for the differentiation of T lymphocytes is reduced, especially in protein-calorie malnutrition and zinc deficiency. Confirmation of a T cell maturational defect in nutritional deprivation comes from the observations of decreased total (T3 and rosette-forming) T cells in the peripheral blood of children with kwashiorkor and marasmus, with preferential loss of helper/inducer (T4) T cell subsets. Reduced number and in vitro function of T cells have also been reported in experimental deficiencies of iron, zinc, copper, and vitamins A and E. Loss of cutaneous hypersensitivity to mitogens and antigens is a consistent sequela of dietary deficiencies of protein, vitamins A and C, pyridoxine, iron and zinc. Cell-mediated immunity directed against allogeneic histocompatibility antigens (e.g. mixed leukocyte cultures, graft versus host, skin graft rejection) may actually be enhanced by experimental protein and polyunsaturated fat deficiencies. Alternatively, pyridoxine, ascorbate and biotin deficiencies resulted in delayed rejection of skin allografts. Cytotoxic T lymphocyte (CTL) activity is impaired in zinc-, iron- and copper-deficient mice, as well as in scorbutic guinea pigs. Natural killer (NK) cell function may be either enhanced or depressed, depending upon the nutrient and its effects on interferon production. Several authors have demonstrated normal or enhanced macrophage activity in a variety of experimental deficiencies. The extrapolation of these observations to infectious disease resistance is not straightforward, and depends upon the nature of the microbe, its own nutrient needs, and the relative importance of innate, as opposed to immunologic, defense mechanisms.  相似文献   

3.
Malnutrition and tuberculosis are both problems mostly of the developing countries. Tuberculosis can lead to malnutrition and malnutrition may predispose to tuberculosis. Poor nutrition leads to protein–energy malnutrition and micronutrients deficiencies which lead to immunodeficiency. This secondary immunodeficiency increases the host's susceptibility to infection and hence increase the risk for developing tuberculosis. Tuberculosis itself leads to reduction in appetite, nutrient malabsorption, micronutrient malabsorption, and altered metabolism leading to wasting and poor nutritional status. Nutritional status and dietary intake and hence nutritional status of patients get improved during antituberculosis treatment.  相似文献   

4.
Nutrition, immune response, and outcome   总被引:3,自引:0,他引:3  
The immune system plays a key role in the body's ability to fight infection and reduce the risk of developing tumors, autoimmune and degenerative disease. Nutritional deficiencies and excesses influence various components of the immune system. Early studies investigating the association between nutrition and immunity focused on generalized protein-energy malnutrition, particularly in children in developing countries. The extent of immunological impairment depends not only on the severity of malnutrition but on the presence of infection and on the age of onset of nutritional deprivation, among other factors. In industrialized nations, immune function has been shown to be compromised in many malnourished hospitalized patients, small-for-gestational age infants, and the elderly. Obesity also may adversely influence immune function. Imbalances of single nutrients are relatively uncommon in humans, and investigations of protein and amino acids and specific vitamins, minerals, and trace elements generally are carried out in experimental animals. Deficiencies of protein and some amino acids, as well as vitamins A, E, B6 and folate, are associated with reduced immunocompetence. In contrast, excessive intake of fat, in particular polyunsaturated fatty acids (e.g. linoleic and arachidonic acids), iron, and vitamin E are immunosuppressive. Trace elements modulate immune responses through their critical role in enzyme activity. Both deficiency and excess of trace elements have been recognized. Although dietary requirements of most of these elements are met by a balanced diet, there are certain population groups and specific disease states which are likely to be associated with deficiency of one or more of these essential elements. The role of trace elements in maintenance of immune function and their causal role in secondary immunodeficiency is increasingly being recognized. There is growing research concerning the role of zinc, copper, selenium, and other elements in immunity and the mechanisms that underlie such roles. The problem of interaction of trace elements and immunity is a complex one because of the frequently associated other nutritional deficiencies, the presence of clinical or subclinical infections which in themselves have a significant effect on immunity, and finally the altered metabolism due to the underlying disease. There are many practical applications of our recently acquired knowledge regarding nutritional regulation of immunity.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

5.
The number and proportion of older adults are increasing globally, and it is predicted that in 2020, there will be 723 million people worldwide aged 66 and older. In recent decades, numerous studies showed that healthy eating is positively associated with better nutritional status and quality of life, and the decreased incidence of noncommunicable diseases. As older adults become health conscious, the demand for foods and beverages rich in nutrients and bioactive compounds has increased. The increased demand for healthy food stimulated a recent rapid increase in designing, producing, and marketing functional foods to prevent or correct nutrient deficiencies and to improve the nutritional status of older adults. These functional products contain and/or are enriched with dietary fiber; omega‐3 polyunsaturated fatty acids; phytoestrogens; polyphenols; carotenoids such as alpha‐ and beta‐carotene; lutein and zeaxanthin; pre‐, pro‐, and synbiotics; and plant sterols and stanols. A limited number of publications have thoroughly addressed the effect of functional foods on the nutritional status of older adults. The goal of this review was to review existing recent research on the role of functional foods in healthy and active aging.  相似文献   

6.
Intensification of the industrial brewing process, particularly the use of higher gravity worts, has been driven by increasing competition within the industry as well as the need to maximise the use of raw materials and minimise energy expenditure. These developments have, however, placed greater demands on brewing yeast strains, whose evolutionary history has not prepared them for the extreme conditions associated with higher gravity brewing. Various yeast nutrient supplements have been used or proposed to maintain yeast performance under stressful conditions. These have included specific metal ions, lipids and lipid components such as fatty acids and sterols and free amino nitrogen, usually supplied in the form of a complex yeast food. Correction of wort nutritional deficiencies may reduce stress sensitivity of yeast and improve fermentation performance. Potential negative consequences of altering wort composition must however be considered, as important beer quality attributes such as taste, stability and foam can be affected. Here, the various options for nutrient supplementation and their influence on yeast physiology and performance, as well as beer characteristics are considered.  相似文献   

7.
The maternal nutritional status is considered as one of the most important factors influencing the pregnancy and the state of the offspring. There are limited data available on inadequate intake, especially before conception. A variety of nutritional and non-nutritional factors can act during the preconceptional period. Prepregnancy body weight and gestational weight gain have an independent but cumulative influence on the birth weight. The vitamin deficiency in preconceptional period, especially of folates, seems to be associated with neural tube defects. The infants of women with total gestational weight gain below 9 kg have the mean birth weight always lower than those of women with weight gain more than 9 kg in all three categories of preconceptional relative weight (i.e. less than 95%, from 95% to 105% and greater than 105%). Also the proportion of infants with birth-weight greater than 2500 g is higher in average (6.2%) and under-weight (4.4%) groups than in those over-weight (1.8%). Several other maternal nutritional as well as non nutritional variables are related with the pregnancy outcome. Among those with harmful effect on pregnancy outcome since preconceptional period, are alcohol drinking and smoking. Work outside the home can be associated with preterm deliveries and low-birth-weight infants, but the results are not consistent. Nutritional intervention, energy and/or protein supplementation also contribute to an increase of the birth-weight. As far as the antenatal care is concerned, only few studies investigated, with a scientific rigour the relation if any between prenatal care and pregnancy outcome. We concluded that the available evidence confirms a significant impact of preconceptional nutrition on pregnancy outcome. A sensitive evaluation of nutritional status in preconceptional period seems to be a positive strategy for prevention of at risk pregnancies. There is a clear need of prospective human studies with aim to relate the nutrient status of future mother to the evolution of her pregnancy.  相似文献   

8.
Breast cancer, which presents the highest global incidence of all female cancers, is caused by the interaction of genetic and environmental factors. Among the latter, diet has attracted considerable attention, as it is a modifiable risk factor and thus offers an opportunity to design preventive strategies. Nevertheless, only alcohol consumption has been unequivocally related to increased breast cancer risk. Despite the failure of observational studies in human populations to clearly define the nature of the relationship between specific nutrient exposures and breast cancer risk, in vivo and in vitro studies strongly suggest its existence. Moreover, studies at the molecular level have identified the putative action mechanism by which the nutritional constituents of specific foodstuffs may exert protective or enhancing effects with respect to breast cancer risk. The inadequate experimental design of some observational studies, or the occurrence of measurement errors and/or recall bias during data collection, or insufficient follow-up and subject characterization, may underlie these controversies. By improving the methods used to study the relationship between diet and breast cancer risk, and by applying new technologies linked to novel approaches such as “nutrigenomics,” it might be possible to derive effective recommendations for breast cancer prevention and thus improve anti-cancer treatment.  相似文献   

9.
Nutritional deficiencies are eminent at all socioeconomic levels of the world population and have created a critical need for a reevaluation of the nutritional quality of the food supply. A particular group of vitamers, collectively referred to as folates, has received a great deal of attention due to their significance in human metabolism, their prevalent deficiency worldwide, as well as their complexity of analysis. Severe folate deficiency may result in megaloblastic anemia and is generally attributed to low dietary intake, although it may also result from malabsorption. Such concerns have instigated increased interest in food-fortification programs. In order to ensure appropriate levels of nutrient fortification and optimization of food processes for maximum folate retention, it is of great importance to have a basic understanding of the kinetic behavior of individual vitamers with respect to processing parameters and various environmental conditions. This article reviews kinetic stability of folates as affected by processing conditions, discusses problems associated with current methodology for folate analyses, and integrates this information with the nutritional aspects of folates.  相似文献   

10.
Dietary fiber     
Studies done on dietary fiber (DF) over the past five years are presented in this Review. The involvement of dietary fiber in the control of plasma glucose and lipid levels is now established. Two dietary fiber sources (soybean and fenugreek) were studied in our laboratory and are discussed herein. These sources were found to be potentially beneficial in the reduction of plasma glucose in non-insulin dependent diabetes mellitus subjects. They are shown to be acceptable by human subjects and are easy to use either in a mixture of milk products and in cooking. The mechanism by which dietary fiber alters the nutrient absorption is also discussed. The effect of DF on gastric emptying, transit time, adsorption and glucose transport may contribute to reducing plasma glucose and lipid levels. DF was found to be effective in controlling blood glucose and lipid levels of pregnant diabetic women. Dietary fiber may also be potentially beneficial in the reduction of exogenous insulin requirements in these subjects. However, increased consumption of DF may cause adverse side effects; the binding capabilities of fiber may affect nutrient availability, particularly that of minerals and prolonged and high DF dosage supplementation must be regarded cautiously. This is particularly true when recommending such a diet for pregnant or lactating women, children or subjects with nutritional disorders. Physiological effects of DF appear to depend heavily on the source and composition of fiber. Using a combination of DF from a variety of sources may reduce the actual mass of fiber required to obtain the desired metabolic effects and will result in a more palatable diet. Previously observed problems, such as excess flatus, diarrhea and mineral malabsorption would also be minimized.  相似文献   

11.
A review of methods of low alcohol and alcohol-free beer production   总被引:1,自引:0,他引:1  
The increasing interest of consumers in health and alcohol abuse issues motivates breweries to expand the assortment of products with low alcohol content. The goal of producing beers with low alcohol content can be achieved by two main strategies; namely by gentle removal of alcohol from regular beer and by limited ethanol formation during the beer fermentation. Within these two basic strategies, there are a number of techniques that vary in performance, efficiency and usability. This paper presents an overview and comparison of these techniques and provides an evaluation of sensorial properties of low-alcohol and an alcohol-free beer produced as well as suggests possibilities for their additional improvement.  相似文献   

12.
铁缺乏是全球最为常见的营养缺乏病之一,也是各国的重要公共卫生问题。针对铁缺乏现状,各国制定了一系列铁强化的政策和法规,以改善缺铁性贫血以及铁缺乏相关疾病。本文就目前国内和部分国家食品铁强化法律法规体系、铁强化剂、铁强化食物载体等方面进行论述,为今后我国铁强化政策的修订提供参考。  相似文献   

13.
Health professionals concerned with improving the nutritional status of populations are facing numerous problems ranging from emaciation to overnutrition. This review article addresses the complexity, the relative significance and the interaction of factors leading to the nutritional profile of specific groups and individuals. When availability of food is threatened, the programs designed to reduce the incidence of malnutrition must balance the food supply with energy resources and population needs as well as encourage economic improvement of food distribution systems. For those persons having access to an abundant food supply, social forces and technological factors may affect food patterns, resulting in unbalanced diets associated with chronic diseases. Misinterpretation of reliable scientific findings is a major cause of abnormal nutrition behaviour. Overreaction to health messages may precipitate such conditions as anorexia nervosa or nutrient toxicity. Adverse food reactions, real or imagined, lead to restrictions in food selection. Excessive austerity in food use negates the pleasure of eating, a useful mechanism in food choice ensuring food diversity.  相似文献   

14.
BACKGROUND: In spite of the strides made globally in reducing hunger, the problems of micronutrient deficiencies and coexisting obesity and related cardiovascular and degenerative diseases constitute a formidable challenge for the future. Attempts to reverse this trend with single-nutrient intervention strategies have met with limited success, resulting in renewed calls for food-based approaches. The deployment of agricultural biodiversity is an approach that entails greater use of local biodiversity to ensure dietary diversity. OBJECTIVE: To outline a new strategy proposed by the International Plant Genetic Resources Institute (IPGRI) that employs agricultural biodiversity as the primary resource for food security and health. METHODS: The authors carried out a meta-analysis to review and assemble existing information on the nutritional and healthful properties of traditional foods based on a diverse set of case studies and food composition and nutritional analysis studies. The methods highlight particular examples of foods where analysis of nutrient and non-nutrient composition reveals important traits to address the growing problems of malnutrition associated with the rise of chronic diseases. Finally, the authors analyze social, economic, and cultural changes that undermine the healthful components of traditional diets. RESULTS: Based on this multidisciplinary and comparative approach, the authors suggest a holistic food-based approach that combines research to assess and document nutritional and healthful properties of traditional foods, investigating options in which nutritionally valuable traditional foods can contribute to better livelihoods, and ways that awareness and promotional campaigns can identify healthful components of traditional diets that fit the needs of urban and market-oriented consumers. CONCLUSIONS: There is an urgent need for agricultural research centers, national agricultural research systems, universities, and community-based organizations to work together under a shared policy framework with the aim of developing a strong evidence base linking biodiversity, nutrition, and health. Although these initiatives are still ongoing, the gains realized in small-scale and local pilot efforts have encouraged IPGRI to work with local partners toward the implementation of scale-up efforts in various regions.  相似文献   

15.
Rice is a staple food for more than 3 billion people in more than 100 countries of the world but ironically it is deficient in many bioavailable vitamins, minerals, essential amino- and fatty-acids and phytochemicals that prevent chronic diseases like type 2 diabetes, heart disease, cancers, and obesity. To enhance the nutritional and other quality aspects of rice, a better understanding of the regulation of the processes involved in the synthesis, uptake, transport, and metabolism of macro-(starch, seed storage protein and lipid) and micronutrients (vitamins, minerals and phytochemicals) is required. With the publication of high quality genomic sequence of rice, significant progress has been made in identification, isolation, and characterization of novel genes and their regulation for the nutritional and quality enhancement of rice. During the last decade, numerous efforts have been made to refine the nutritional and other quality traits either by using the traditional breeding with high through put technologies such as marker assisted selection and breeding, or by adopting the transgenic approach. A significant improvement in vitamins (A, folate, and E), mineral (iron), essential amino acid (lysine), and flavonoids levels has been achieved in the edible part of rice, i.e., endosperm (biofortification) to meet the daily dietary allowance. However, studies on bioavailability and allergenicity on biofortified rice are still required. Despite the numerous efforts, the commercialization of biofortified rice has not yet been achieved. The present review summarizes the progress and challenges of genetic engineering and/or metabolic engineering technologies to improve rice grain quality, and presents the future prospects in developing nutrient dense rice to save the everincreasing population, that depends solely on rice as the staple food, from widespread nutritional deficiencies.  相似文献   

16.
To improve the difficulties related to malnutrition, nutritional support has become an essential part of multidisciplinary comprehensive treatment for cancer. Lipids are essential nutrient source for the human body, and nowadays in clinical practices, it has a positive interventional effect on patients suffering from cancer. However, contribution of lipids in nutritional support of cancer patients is still poorly understood. Moreover, the sensory and physicochemical properties of lipids can severely restrict their applications in lipid-rich formula foods. In this review article, for the first time, we have presented a summary of the existing studies which were related to the associations between different lipids and improved malnutrition in cancer patients and discussed possible mechanisms. Subsequently, we discussed the challenges and effective solutions during processing of lipids into formula foods. Further, by considering existing problems in current lipid nutritional support, we proposed a novel method for the treatment of malnutrition, including developing individualized lipid nutrition for different patients depending on the individual's genotype and enterotype. Nonetheless, this review study provides a new direction for future research on nutritional support and the development of lipid-rich formula foods for cancer patients, and probably will help to improve the efficacy of lipids in the treatment of cancer malnutrition.  相似文献   

17.
酵母菌与我们生活密不可分,已在食品、饮料、饲料、工业乙醇等领域得到广泛应用。酵母菌除了发酵功能外,在益生方面也显示出了重要作用。与传统益生菌相比,酵母菌在治疗腹泻疾病、提高免疫力、增强营养等方面都有显著效果,且酵母菌的代谢产物(二氧化碳和乙醇)对食品种类和风味都有积极贡献。酵母菌在食品中应用的文献数不胜数,但描述其益生功能的文献却不多。本文综述了近几年有关酵母菌在抑菌、降胆固醇、治疗腹泻方面的研究进展以及在酒、乳品、酵素生产中的应用,同时对酵母菌的安全性、应用局限及未来发展做了展望。  相似文献   

18.
Immobilized lipase from Candida antarctica was employed to convert triglycerides to biodiesel using alcohol. Immobilized lipase is frequently deactivated by lower alcohols with deactivation being caused by the immiscibility between triglycerides and methanol or ethanol. When the lower alcohol is adsorbed to the immobilized enzyme, the entry of triglycerides is blocked, which causes the reaction to stop. An alcohol with three or more carbon atoms, preferably 2-butanol or tert-butanol, can regenerate the deactivated immobilized enzyme. The present work established that the activity of immobilized lipase could be significantly increased when such alcohols were used for an immersion pretreatment of the enzyme. The activity of the commercially available immobilized enzyme, Novozyme 435, increased about tenfold in comparison to the enzyme not subjected to any pretreatment. Following complete deactivation of the enzyme by methanol, washing with 2-butanol and tert-butanol successfully regenerated the enzyme and restored it to about 56% and 75% of its original activity level, respectively.  相似文献   

19.
Gene-nutrient interactions during fetal development   总被引:1,自引:0,他引:1  
Eukaryotic cells have evolved a complex series of nutrient sensors that protect them from damage caused by acute deficiencies and also mediate adaptive responses to prolonged excess or deficiency of particular nutrients. In adults gene expression is regulated by nutrients interacting with pathways involving mammalian target of rapamycin (mTOR), CCAAT/enhancer-binding proteins (C/EBPs) and peroxisome proliferator activator proteins (PPARs). These systems are also present in key cells of the developing oocyte, embryo and fetus. In this review we will consider the role of interactions between genes and nutrients during reproduction with a particular emphasis on their possible involvement in the prenatal programming of glucose metabolism in the adult.  相似文献   

20.
Zinc, exercise, and thyroid hormone function.   总被引:1,自引:0,他引:1  
During the last 3 decades, remarkable advances have taken place in the field of zinc metabolism. Thirty years ago, only three enzymes that required zinc for their activities were identified; today more than 200 such enzymes have been classified. Zinc plays a vital role in human nutrition and biochemical function. Prior to 1963, zinc deficiency in humans was unknown. Today, it is recognized that a nutritional deficiency of zinc is common throughout the world, including the U.S.A marginal deficiency of zinc appears to be prevalent in many segments of populations in developed countries, and more severe deficiencies are widespread in many parts of the world. Therefore, it is important that proper steps to correct zinc deficiency are taken. However, the assessment of zinc nutriture has always proven to be a difficult problem because no reliable measure of zinc status currently exists. More recently, it has been recognized that zinc may play an important role in thyroid hormone metabolism, although the exact mechanism by which zinc affects thyroid hormone function is far from clear. In addition, exercise has been shown to alter zinc status. This review will focus on the relationship among zinc status, exercise, and thyroid hormone function.  相似文献   

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