Retinoids are low molecular weight, lipophilic derivatives of vitamin A which have a profound effect upon the development of a diverse array of animals. Here, I review these effects on Invertebrates: a colonial hydroid, a colonial ascidian, and Vertebrates: the regenerating amphibian limb, the developing chick limb bud, the regenerating amphibian tail, the anteroposterior axis of the early embryo, the developing chick embryo skin. There is a striking uniformity of effect of retinoids on pattern formation when applied to these (...) diverse organisms. The majority react by being posteriorized in their development, although additional effects can also be seen. Several hypotheses which can explain these results are discussed along with the deduction that they lead to: retinoids may be components of a universal developmental mechanism or they may simply act in a similar way to alter a universal developmental mechanism. In either case the experimental analysis of retinoid effects on development has important implications for the evolution of developmental mechanisms. (shrink)

Over the past several years, discoveries from mouse genetics have had direct impact on our understanding of vitamin A metabolism. Although the metabolism of vitamin A in the mouse does have some special features (for example very large stores of liver and pulmonary retinyl esters), the ability to construct knockout and transgenic mouse models has yielded an impressive amount of information directly relevant to understanding the general principles of vitamin A transport, storage and degradation. We discuss below (...) the metabolism of vitamin A through a number of genetically engineered mouse strains with alterations in genes that affect this metabolism. The novelty of this experimental approach is evidenced by the fact that the oldest of these strains was first reported only eight years ago.1) BioEssays 23:409–419, 2001. © 2001 John Wiley & Sons, Inc. (shrink)

The conventional view of vitamins reflects a diverse group of small molecules that facilitate critical aspects of metabolism and prevent potentially fatal deficiency syndromes. However, vitamins also contribute to the shaping and maintenance of the human phenome over lifecycle and evolutionary timescales, enabling a degree of phenotypic plasticity that operates to allow adaptive responses that are appropriate to key periods of sensitivity (i.e., epigenetic response during prenatal development within the lifecycle or as an evolved response to environmental challenge over a (...) great many lifecycles). Individually, vitamins are important, but their effect is often based on nutrient‐nutrient (vitamin‐vitamin), nutrient‐gene (vitamin‐gene), and gene‐gene interactions, and the environmental influence of shifting geophysical cycles, as well as evolving cultural practices. These ideas will be explored within what I refer to as the “adaptive vitome (vitomics)” paradigm. (shrink)

Inborn errors of vitamin B12 (cobalamin) metabolism are associated with homocystinuria and methylmalonic aciduria, either alone or in combination. A number of these disorders have provided the first evidence for the existence of important steps in the transport or metabolism of cobalamin in eukaryotic cells. Eight complementation classes have been defined on the basis of somatic cell hybridization studies. Although the majority of patients present in infancy or early childhood, some are not diagnosed until adolescence or later. For some (...) of these disorders, prenatal diagnosis and therapy with cobalamin during pregnancy has been attempted. Although only males have been described with cblE disease, all of these disorders are presumed to be autosomal recessive in inheritance. The clinical and laboratory aspects of the different complementation classes (cblA–cblG) are reviewed here. (shrink)

Analysis of a diverse cross‐sample of plant‐insect interactions suggests that the abundance of vitamin C (L‐ascorbic acid, ascorbate or AsA) in plants influences their susceptibility to insect feeding. These effects may be mediated by AsAs roles as an essential dietary nutrient, as an antioxidant in the insect midgut, or as a substrate for plant‐derived ascorbate oxidase, which can lead to generation of toxic reactive oxygen species. Ascorbate can also influence the efficacy of plant defenses such as myrosinases and tannins, (...) and alter insects' susceptibility to natural enemies. Conversely, herbivores appear to influence both de novo synthesis and redox cycling of AsA in their host plants, thereby potentially altering the nutritional value of crops and their susceptibility to pests. The recent development of genetically modified crops with enhanced AsA content provides both an impetus and a tool set for further studies on the role of AsA in plant‐insect interactions. (shrink)

The US FDA currently encourages the addition of vitamin D to milk and cereals, with the aim of reducing rickets in children and osteoporosis in adults. However, vitamin D not only regulates the expression of genes associated with calcium homeostasis, but also genes associated with cancers, autoimmune disease, and infection. It does this by controlling the activation of the vitamin D receptor (VDR), a type 1 nuclear receptor and DNA transcription factor. Molecular biology is rapidly coming to (...) an understanding of the multiplicity of roles played by the VDR, but clinical medicine is having difficulty keeping up with the pace of change. For example, the FDA recently proposed a rule change that will encourage high levels of vitamin D to be added to even more foods, so that the manufacturers can claim those foods “reduce the risk of osteoporosis”. The FDA docket does not review one single paper detailing the transcriptional activity of vitamin D, even though, on average, one new paper a day is being published on that topic. Nor do they review whether widespread supplementation with vitamin D, an immunomodulatory secosteroid, might predispose the population to immune dysfunction. This BioEssay explores how lifelong supplementation of the food chain with vitamin D might well be contributing to the current epidemics of obesity and chronic disease. BioEssays 30:173–182, 2008. © 2008 Wiley Periodicals, Inc. (shrink)

Abstract: Potatoes are edible tubers, available worldwide and all year long. They are relatively cheap to grow, rich in nutrients, and they can make a delicious treat. The humble potato has fallen in popularity in recent years, due to the interest in low-carb foods. However, the fiber, vitamins, minerals, and phytochemicals it provides can help ward off disease and benefit human health. They are an important staple food in many countries around the world. There are an estimated 200 varieties of (...) potatoes, which can be classified into a number of categories based on the cooked texture and ingredient functionality. Using a public dataset of 2400 images of potatoes, we trained a deep convolutional neural network to identify 4 types (Red, Red Washed, Sweet, and White).The trained model achieved an accuracy of 99.5% of test set, demonstrating the feasibility of this approach. (shrink)

Avi Shulman has taught thousands of people how to look at life and see positive ways to make everything better. In this precious collection of his astute observations, he shares a wealth of wisdom in his concise and simple manner that always hits the target and makes the reader ask himself, why didn't I think of that? With lessons on assuming responsibility, setting attainable goals, creating a warm atmosphere at home, and avoiding the feeling of burnout, Vitamins for the Spirit (...) is a joy to read and an incredible investment in your future happiness and success. (shrink)

The concept of quality of life is the basis for a new paradigm of clinical medicine. Its assessment is considered to be an important instrument in determining disease severity and effectiveness of different treatment modalities. Our studies are devoted to the problem of diabetes complications especially anemia in patients with diabetic kidney disease. Anemia in subjects with diabetic nephropathy may result from various pathogenic factors including erythropoietin deficiency, iron deficiency, vitamin B12 and/or folate deficiencies, the effects of proinflammatory cytokines (...) etc. Diabetic patients with anemia are at increased risk of cardiovascular accidents and death. The aim of this study was to assess the influence of anemia on the quality of life of patients with early stages of diabetic nephropathy. We investigated 127 patients with type 2 diabetes mellitus and early diabetic nephropathy. Anemia was defined according to the World Health Organization criteria. Anemic patients were divided into three groups according to the stage of chronic kidney disease. Patients’ quality of life was assessed with SF-36 health survey. Anemic patients had lower scores of physical role functioning and emotional role functioning as compared to the patients with normal hemoglobin level, irrespective of the stage of chronic kidney disease. Patients with anemia and chronic kidney disease stage 3 had lower scores of general health perceptions, physical functioning, bodily pain, vitality and mental health than patients in the non-anemic group. Social role functioning was similar in anemic and non-anemic patients. The possible mechanisms and implications of the above mentioned findings are discussed with a medical and humanitarian perspective. The directions of further studies are proposed. (shrink)

Abstract: Tomatoes are part of the major crops in food security. Tomatoes are plants grown in temperate and hot regions of South American origin from Peru, and then spread to most countries of the world. Tomatoes contain a lot of vitamin C and mineral salts, and are recommended for people with constipation, diabetes and patients with heart and body diseases. Studies and scientific studies have proven the importance of eating tomato juice in reducing the activity of platelets in diabetics, (...) which helps in protecting them from developing deadly blood clots. A tomato classification approach is presented with a data set containing approximately 5,266 images with 7 species belonging to tomatoes. The Neural Network Algorithms (CNN), a deep learning technique applied widely in image recognition, is used for this task. (shrink)

A high percent of oxidative energy metabolism is needed to support brain growth during infancy. Unhealthy diets and limited nutrition, as well as other environmental insults, can compromise these essential developmental processes. In particular, iron deficiency anemia has been found to undermine both normal brain growth and neurobehavioral development. Even moderate ID may affect neural maturation because when iron is limited, it is prioritized first to red blood cells over the brain. A primate model was used to investigate the neural (...) effects of a transient ID and if deficits would persist after iron treatment. The large size and postnatal growth of the monkey brain makes the findings relevant to the metabolic and iron needs of human infants, and initiating treatment upon diagnosis of anemia reflects clinical practice. Specifically, this analysis determined whether brain maturation would still be compromised at 1 year of age if an anemic infant was treated promptly once diagnosed. The hematology and iron status of 41 infant rhesus monkeys was screened at 2-month intervals. Fifteen became ID; 12 met clinical criteria for anemia and were administered iron dextran and B vitamins for 1–2 months. MRI scans were acquired at 1 year. The volumetric and diffusion tensor imaging measures from the ID infants were compared with monkeys who remained continuously iron sufficient. A prior history of ID was associated with smaller total brain volumes, driven primarily by significantly less total gray matter and smaller GM volumes in several cortical regions. At the macrostructual level, the effect on white matter volumes was not as overt. However, DTI analyses of WM microstructure indicated two later-maturating anterior tracts were negatively affected. The findings reaffirm the importance of iron for normal brain development. Given that brain differences were still evident even after iron treatment and following recovery of iron-dependent hematological indices, the results highlight the importance of early detection and preemptive supplementation to limit the neural consequences of ID. (shrink)

Vitamin D deficiency and its effect have attracted considerable research interest due to its relation to glucose homeostasis, insulin secretion, sensitivity and synthesis. This study aimed to evaluate vitamin D levels in patients with type II diabetes mellitus aged between 35-65 years and investigate their relations with glycemic control and obesity. The study included 74 Libyan patients with a known history of type II diabetes mellitus (33 males and 41 females). Serum glucose, glycosylated hemoglobin (HbA1c) and vitamin (...) D levels were biochemically estimated in these patients. Further, body mass index (BMI) was calculated for all diabetic patients (weight in kilogram per height in meter square). The mean level of plasma glucose level was 150.58±63.82 mg/dl (mean±SD). The mean of HbA1c level was 7.90±8.48% (mean±SD). The mean level of vitamin D was 22.75±14.97 ng/ml. The mean of BMI was 26.55±4.10 Kg per m2. The findings showed that 58.10% of the cases had vitamin D deficiency (Out of which 24.24% were males and 85.36% were females). This study showed significant differences in glucose, HbA1c, vitamin D and BMI between male and female patients. Moreover, elderly ages for both sexes had adverse effects on vitamin D status. Vitamin D levels have negatively been correlated with levels of glucose, HbA1c and BMI. It is concluded that vitamin D deficiency has an adverse effect on glucose homeostasis in patients with type II diabetes mellitus and this can be a contributing risk factor in complications of type II diabetes mellitus development in Libyan patients. (shrink)

The discovery that some B vitamins are constituents of respiratory coenzymes led to the development of an interfield theory of the kind discussed by Darden and Maull. In this paper it is shown that the development of a useful interfield connection was made possible by two reconceptualizations: a reconceptualization that united two then-distinct fields giving rise to the concept of vitamins as dietary substances; and another reconceptualization that united two approaches to respiratory metabolism producing the idea that coenzymes are transport (...) vehicles. (shrink)

General knowledge of the role of vitamin D3 in human physiology has been shaped by its discovery as a preventive agent of nutritional rickets, a defect in bone development due to inadequate uptake of dietary calcium. Studies on the function of the hormonal form of vitamin D3, 1α,25‐dihydroxyvitamin D3, have been greatly accelerated by the molecular cloning and structural analysis of the vitamin D3 receptor, which is a ligand‐activated regulator of gene transcription. Molecular genetic techniques including genomics (...) have helped reveal that 1α,25‐dihydroxyvitamin D3 can control more than calcium homeostasis. It has widespread effects on cellular differentiation and proliferation, and can modulate immune responsiveness, and central nervous system function. Moreover, accumulating epidemiological and molecular evidence suggests that 1α,25‐dihydroxyvitamin D3 acts as a chemopreventive agent against several malignancies including cancers of the prostate and colon. Here, we survey the most‐recent findings and discuss their implications for the potential therapeutic uses of vitamin D analogues. BioEssays 26:21–28, 2004. © 2003 Wiley Periodicals, Inc. (shrink)

Biochemists investigating the problem of the vitamins in the early years of the twentieth century were working without an object, as such. Although they had developed a fairly elaborate idea of the character of the ‘vitamine’ and its role in metabolism, vitamins were not yet biochemical objects, but rather ‘functional ascriptions’ and ‘explanatory devices’. I suggest that an early instance of the changing status of the object of the ‘vitamins’ can be found in their stabilization, through the course of World (...) War I, as bio-political objects for the British and Allied war effort. Vitamins emerged as players, active agents, in Britain’s wartime bio-political problems of food distribution and population health and because of this they became increasingly real as bio-political objects, even prior to their isolation as bio-chemical molecules. I suggest that the materiality of our biology has agency in the development of political regimes and schemes. (shrink)

Introduction: Globally, vitamin D deficiency is one of the most common deficiencies, affecting nearly half the world's population. The objective of this survey was to assess and compare the knowledge about vitamin D and the perceived state of health in Emirati and international tourist female students in Dubai, UAE. Methods: This is a cross-sectional study that took place in universities in Dubai, UAE. This survey consisted of 17 multiple choice questions. The first part of the survey assessed levels (...) of supplementation, diet and UV exposure. Another section evaluated the participants’ self-assessed state of health regarding vitamin D testing, symptoms related to vitamin D deficiency and general welbeing. The collected data were statistically analyzed using SPSS statistics for windows version 26.0 (SPSS Inc., Chicago, IL). Statistical significance was set at P<0.05. Results: 105 respondents were Emiratis and 65 were international students. The average age was 21, with an average BMI 23.3. Almost one-third of each group reported using Vitamin D supplements once weekly. The majority of both groups reported rarely getting tanned. Almost all participants reported regular consumption of Vitamin-D rich foods. In both groups, more than half reported consuming milk and cheese regularly and up to one-third reported consuming fish in a regular manner. Although more than half of the students rated their health as good; more than two-thirds reported experiencing muscle pain; only half reported having their blood Vitamin D levels measured once; half reported experiencing problems with concentration and more than three-quarters reported experiencing bad mood in the past month. The prevalence of these symptoms was almost similar across different categories of vitamin D supplementation, tanning habits, dietary intake, or nationality. No statistically significant differences were noted between the 2 groups. Conclusion: more Emirati students were aware of the association between vitamin D and osteoporosis than International tourist students (40% vs. 21.9%, respectively; p<0.05). On the other hand, both groups had lower knowledge about the relationship between vitamin D deficiency and depression, Rheumatoid Arthritis and Hypertension, and the optimal vitamin D level; however, no statistically significant differences were noted regarding this knowledge of Emiratis and international students. (shrink)

It is estimated that over 800 million people are hungry each day and two billion are suffering from the consequences of vitamin and mineral deficiencies. While a paradigm shift towards a multi-dimensional and multi-sectoral approach to food and nutrition insecurity is emerging, technical approaches largely prevail to tackle the causes of hunger and malnutrition. Founded in original in-depth field research among smallholder farmers in southwest Kenya, we argue that incorporating cultural or social dimensions in this technical debate is imperative (...) and that by systematically overlooking these dimensions, food insecurity cannot be accurately captured nor properly addressed. Based on a sub-location in rural southwest Kenya where the food plate is rapidly narrowing towards a high-calorie low nutrient diet and where over 80 % of households experience food shortages at least once a year, conclusions suggest that preferences, the local function of food, and the practices that emerge therefrom can affect the regularity of meals and their composition. The findings allow us to complement emerging research and program development with a more comprehensive and locally adapted approach to tackle food and nutrition insecurity. (shrink)

Despite efforts from regulatory agencies (e.g. NIH, FDA), recent systematic reviews of randomised controlled trials (RCTs) show that top medical journals continue to publish trials without requiring authors to report details for readers to evaluate early stopping decisions carefully. This article presents a systematic way of modelling and simulating interim monitoring decisions of RCTs. By taking an approach that is both general and rigorous, the proposed framework models and evaluates early stopping decisions of RCTs based on a clear and consistent (...) set of criteria. The framework allows decision analysts to generate and quickly answer ‘what-if’ questions by simulating alternate trial scenarios. I illustrate the framework with a case study of an RCT that was stopped early due to harm. This was a trial of vitamin A supplement in relation to HIV transmission from mother-to-child through breastfeeding. (shrink)

Pyridoxal 5′‐phosphate, the vitamin B6 derivative, acts as the coenzyme of many enzymes involved in amino acid metabolism. Exceptionally, this compound was found covalently bound to glycogen phosphorylase, the key enzyme in the regulation of glycogen metabolism. Although it is essential for the function of phosphorylase, its direct role has remained an enigma. We have recently found that the glucose moiety of pyridoxal (5′)diphospho (1)‐α‐D‐glucose, a conjugate of pyridoxal 5′‐phosphate and glucose 1‐phosphate through a pyrophosphate linkage, is transferred to (...) the nonreducing end of glycogen, forming a new α‐1,4‐glucosidic linkage. This finding emphasizes the importance of the direct phosphate‐phosphate interaction between the coenzyme and the substrate in the phosphorylase catalytic reaction. We have proposed a catalytic mechanism for phosphorylase in which the phosphate group of pyridoxal 5′‐phosphate acts as an electrophile to the phosphate group of glucose 1‐phosphate. This appears to represent the first instance of the direct involvement of a phosphate group in catalysis by enzymes. (shrink)

Assess to quality diets is a basic human right. Geographical challenges and cultural traditions have contributed to the widespread malnutrition present among ethnic minorities of mountainous areas in Northwest Vietnam. Home gardens can play a role in increased diet diversity and micronutrient intakes. However, low production yields and plant diversity in ethnic home gardens have limited their contributions to household food security and nutrition. The pilot study tested a home garden intervention in weekly vegetable harvests and increasing household production and (...) consumption of diverse vegetables year-round. Food ethics issues encountered included limited access to quality food by resource-poor groups, conflicts arising from low preference and value given to some nutritious foods, limited access to information and technology for food production and consumption, each of which were addressed in the study design. The intervention includes: (1) nutrition-focused home garden training and (2) locally-adapted home garden packages consisting of garden planning, technical assistance, and high-yielding seed varieties. Twenty households from two ethnic villages in Son La province participated in the study and were randomly assigned into two groups (intervention and non-intervention). The total vegetable supply from weekly harvests of home garden produce was significantly higher in the intervention households (226 kg) compared to the non-intervention households (39 kg). The intervention group yielded 5.8 and 1.7 times more vegetables by weight and weight per area than those without the intervention. The vegetables were mainly consumed at home for both groups, but the intervention households gave more vegetables as gifts to neighbors. The intervention group cultivated a higher diversity of vegetables with a total of 42 different vegetables compared to 24 in the non-intervention group, which is reflected in an overall higher nutritional yield of vitamin A, iron, other micronutrients and phytochemicals. The home garden training significantly improved the amount, diversity and continuity of household food and nutrient supply. The home garden model is effective and could be scaled up to improve household vegetable supply and consumption, particularly in Northwest Vietnam. (shrink)

The physiology of plant hormones was one of the most dynamic fields in experimental biology in the 1930s, and an important part of T. H. Morgan's influential life science division at the California Institute of Technology. I describe one episode of plant physiology research at the institution in which faculty member James Bonner discovered that the B vitamin thiamin is a plant growth regulator, and then worked in close collaboration with the Merck pharmaceutical firm to develop it as a (...) growth-boosting agrichemical. This episode allows one to draw continuities between certain fields of life science in the United States circa 1940 and the biotechnology industry today, and also foregrounds a number of similarities between plant physiology of the late 1930s and the molecular biology of the period. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:A Response to Susan Laird, “Musical Hunger: A Philosophical Testimonial of Miseducation”Heidi WesterlundCan hunger and satisfaction, which according to John Dewey form “the arsis and thesis of a child’s life,”1 create the rhythm and heartbeat of music education? Susan Laird shows us through her autobiographical experiences how this heartbeat was missed in her case, while the undertone of her narrative and testimonial begs a wider self-reflection upon the culture (...) of music education. Indeed, Laird’s testimonial assumes that musical hunger has something to do with professional music educators; that musical hunger and satisfaction while setting the beat for a person’s musical life are not simply biological functions—something that exists and stays no matter how and what the person is fed or where and with whom the person eats. As Dewey wrote,[t]he very tendency of the child, while hungry, to recall his previous satisfaction, and to anticipate the coming one, is the beginning of the recognition of time. It grows more definite and accurate just in the degree in which all experiences are related to each other as members of one whole.2The imaginative musical dinner table that Laird’s testimonial lays out calls for music educators to reflect upon what kind of meal is served, not only from their own perspective but also from that of their students. Yet, reconstructing the menu is demanding in a profession that struggles with the pros and cons of a tradition in which teachers have learnt to teach in the same way that they themselves have been taught, also teaching using the same order in which they have learned—only hoping to do it more effectively.Quite recently, when visiting the recording studio at the Sibelius Academy department of music education to listen to one of my student’s work with her own rock band, I was reminded by my own remembrances of the difficulty, as well as the necessity, of reconstructing traditions in music teacher education. My thoughts led me fleetingly back to the ‘70s when making arrangements, improvisations, or working in recording studios were part of my musical life, until they were overwhelmed by the then-prevalent diet of professional music studies. Although my experiences of general music education were similar to those of Laird, teachers in the specialized music school fed me with goal-directed instruction in more than one instrument, in music theory, solfege, and the history of Western [End Page 81] art music. Looking back, however, I was lucky in more ways than one: my adolescent leisure time was blessed with numerous choirs, orchestras, and gigging bands—bringing a self-organized satisfaction and motivation to all kinds of music and musical activities. Multiple diets were feeding my musical life: I obtained the strengthening vitamin drops and enjoyed my self-made smorgasbord with family and friends, none of which had been enough by themselves to lead me into the profession. Yet, when entering the university to pursue my professional music studies, I experienced events in reverse order to that which Lucy Green describes in How Popular Musicians Learn.3 As I then did not have a piano of my own, I only had the opportunity to practice what was necessary for exams and so I practically stopped playing for fun. I also realized that not all flute teachers were able to accompany their students as did my first teacher, and so I had to play my flute repertoire for most of the year only imagining how the pieces would sound as a whole with no community with whom to share the joy of music making. While watching my student working in front of the studio desk searching for the right bass sound for her own song—a song that she was performing with friends and fellow students—to give the song the final touch for her work for the pedagogy of African-American music (popular music) course, to my own surprise I suddenly felt a long-forgotten hunger and desire. I was reminded of the challenges facing teacher education in exemplifying by its own practices a music education that does not take for granted that particular subject content or official... (shrink)

This article is aimed to compare the efficacy and acceptability of exercise intervention with other nonpharmacological therapies in improving attention in ADHD patients and then rank those therapies. Methods. Relevant RCT studies from the Cochrane Library, Web of Science, Psycinfo, and PubMed were systematically searched from January 2011 to January 2020. The literature was screened, and the researchers extracted and used Stata16 and WinBugs1.4 independently to analyze the data. Results. The improvement of “attention deficit” in ADHD patients was measured in (...) 83 independent studies with 4,998 participants and 14 nonpharmacological therapies. Therapies were ranked as follows, according to the efficacy and acceptability of the cumulative probability area under the curve : meditation and cognitive; sport intervention therapy; vitamin and mineral; cognitive behavioral therapy; computer training; psychological education; working memory training; neurofeedback therapy; polyunsaturated fatty acids; mineral supplements; meditation; vitamin; biofeedback therapy; and school-based training. However, because the effect size of meditation and cognitive therapy was at a marginally significant level ), the robustness of the results was far lower than that of sport intervention therapy. Therefore, careful interpretation is needed in practice. Conclusion. Considering the efficacy and acceptability of various nonpharmacological therapies, sport intervention has a more stable effect on the improvement of attention deficit. Secondly, meditation and cognitive therapy, cognitive behavioral therapy, and computer training can also be effective complementary tools. (shrink)

Modern medicine has produced many successful theories concerning the causes of diseases. For example, we know that tuberculosis is caused by the bacterium Mycobacterium tuberculosis, and that scurvy is caused by a deficiency of vitamin C. This chapter discusses the nature of medical theories from the perspective of the philosophy, history, and psychology of science. I will review prominent philosophical accounts of what constitutes a scientific theory, and develop a new account of medical theories as representations of mechanisms that (...) explain disease. An account of the nature of medical theories should illuminate many aspects of the development and application of medical knowledge. Most importantly, it should contribute to understanding of medical explanation, both at the general level of causes of diseases and at the individual level of diagnosis of particular cases of a disease. Medical researchers seek to explain the causes of diseases such as tuberculosis, while physicians seek to identify diseases that explain symptoms such as fever. A medical theory such as the bacterial theory of tuberculosis provides good explanations at both the general and individual levels. The primary aim of this chapter is to show how these explanations work. A secondary aim is to show how an account of medical theories can shed light on other aspects of medical research and practice, including the nature of medical discovery, the process of evaluation of competing medical theories, and the ways in which effective treatments of disease depend on the development of good mechanistic theories about diseases. (shrink)

Related to the research of working conditions, the link between organizational factors and health was traditionally analyzed using linear models. However, the literature analysis suggests inconsistencies in linear models predicting workers’ health levels. To clarify this issue, this exploratory research compares the linear and non-linear relationships between job demands-resources, and the psychological and physical symptoms of employees working in the main five service subsectors: commerce, horeca, public administration, education, and healthcare. With a final sample of 4,047 participants, our study data (...) were extracted from the II Andalusian Working Conditions Survey. Following the theoretical framework of JD-R Model and considering the Vitamin Model theoretical approach for non-linear relationships, our results showed that there were significant differences among the five subsectors analyzed regarding the linear and non-linear relationships between job demands-resources and psychological and physical symptoms of employees. Furthermore, task complexity generated non-linear relationships in higher proportion than time pressure and contact with users. Likewise, non-linear relationships found showed a U-shape. Moreover, the findings of non-linear relationships suggested that medium levels of task complexity should not be exceeded to avoid further negative impact on psychological and physical symptoms for service sector employees, preserving their health. Finally, some general practical implications of work environment interventions are suggested. (shrink)

Alzheimer's disease remains the most common form of dementia. Dementia symptoms vary depending on individual personality, life experience, and social and cultural influences. As dementia progresses, involvement of multi-disciplinary health care professionals is needed to manage the disease. Alzheimer research is progressing rapidly. While 5% of all Alzheimer's disease may be genetically determined, the majority is not. Susceptibility genes can reveal the risk of contracting Alzheimer's disease. Early life risk factors such as education, nutrition, and vascular disease may increase the (...) likelihood of dementia in later life. In the United States, two acetylcholinesterase inhibitors have been approved as cognitive enhancers. Possible prevention and symptomatic treatment interventions have focused on estrogen replacement therapy, antioxidants, and anti-inflammatory medications. Research advances have improved the clinical management of dementia. Ethical implications to the patient, family, and society are multiple and remain challenging. (shrink)

I here defend some of the positions taken in National Responsibility and Global Justice against criticisms by Nils Holtug. I reinforce my suggestion that claims about national membership being ‘morally arbitrary’ are question begging and try to show how such membership can legitimately serve as a source of special obligations. I examine the claim that the problems involved in constructing a ‘currency’ of global justice also arise in the domestic context and suggest that appealing to ‘welfare’ as the relevant currency (...) is not a useful way of responding to cultural differences. Finally, I respond to the hypothetical case of an unequally distributed life-extending vitamin by arguing that the discovery of such a substance would change our understanding of a normal human life, and thereby raise the bar of sufficiency. Keywords: moral arbitrariness; obligation; national identity; global egalitarianism; sufficiency (Published: 16 September 2011) Citation: Ethics & Global Politics, Vol. 4 , No. 3, 2011, pp. 165-171. DOI: 10.3402/egp.v4i3.8489. (shrink)

Objectives: To explore how subjects in a placebo-controlled vitamin A supplementation trial among Ghanaian women aged 15–45 years perceive the trial and whether they know that not all trial capsules are the same, and to identify factors associated with this knowledge.Methods: 60 semistructured interviews and 12 focus groups were conducted to explore subjects’ perceptions of the trial. Steps were taken to address areas of low comprehension, including retraining fieldworkers. 1971 trial subjects were randomly selected for a survey measuring their (...) knowledge that not all trial capsules are the same. The subjects’ fieldworkers were also interviewed about their characteristics and trial knowledge. Factors associated with knowledge were explored using multi-level modeling.Results: Although subjects knew they were taking part in research, most thought they were receiving an active and beneficial medication. Variables associated with knowledge were education and district of residence. Radio broadcasts benefited those with some schooling. Fieldworkers’ characteristics were not associated with subjects’ knowledge.Conclusions: Research and debate on new or improved consent procedures are urgently required, particularly for subjects with little education. (shrink)

Two essential periods may be identified in the early stages of the history of vitamin D-resistant rickets. The first was the period during which a very well known deficiency disease, rickets, acquired a scientific status: this required the development of unifying principles to confer upon the newly developing science of pathology a doctrine without which it would have been condemned to remain a collection of unrelated facts with very little practical application. One first such unifying principle was provided by (...) the notion of hygiene; while the blanket explanations provided by this notion alone were much too general to enable rickets to achieve scientific status, it did point out the need to look for specific external causes for the disease and to examine the life-style and dietary habits of the patients. The second phase of the conceptualization of the disease was the assumption of a specific cause — that is, using concepts developed in the area of infectious diseases. This was made possible by fundamental similarities between deficiency and infectious diseases, in spite of their apparent differences. Both types of illness have some of the characteristics of what Georges Canguilhem calls the ontological representation of disease as opposed to dysharmonic representations, which primarily concern the endocrine diseases. It is precisely this shift from one to the other manner of perceiving ill health that enabled the identification of the vitamin D-resistant rickets. Conceptualization of the notion of vitamin D resistancy required that the conditions causing the disease be looked for within the organism rather than outside it; this was thus the first time that endocrine concepts were applied to studying the physiology of vitamin D.The history of resistant rickets therefore represents an interesting model for understanding the growth of biomedical knowledge. It allows the development of a number of more general ideas on the question of the relationship between biology and medicine and on the thorny problem of specificity in medical thinking. As far as this topic is concerned it can be seen that there was an ongoing exchange between medical and biological thinking during the initial period up until 1937, and that one could deny any such specificity in medical thinking during this same period. Albright, for example, used human diseases as spontaneously produced models for experimental biology. It was also more feasible for an experimental biologist to administer toxic doses than for a clinician to do so.What, then, if any, is the place of the specificity of medical thinking in this history? The fact that medicine is characterized not only by it ccognitive content78 but also by its final aim, which is to restore health, makes it necessary to take factors other than objective knowledge into consideration. This is particularly evident in two aspects of medicine, therapeutics and nosology, and in approaching the notion of pathological individuality.Therapeutic activity has a largely empirical approach. Many drugs, such as cod-liver oil, were discovered empirically. Treatment often in the past, and still now, has proceeded by trial and error, upon no established theoretical basis. At this level the relationship between biology and medicine is roughly comparable to that between science and technology79 \3- that is, it is impossible to reduce either therapeutics or technical activities to the simple application of basic science. In this sense, the application of vitamin D to vitamin-resistant rickets is quite typical. Further-more, in the case studied here, the therapeutic activity heralds a definite breaking away from the medicatrix naturae of conventional medicine dating back to ancient times, and it embodies a new concept of the organism and of disease: no longer can the diseased organism be thought of as merely having a perturbed equilibrium requiring restoration by means of a natural style of medicine. On the contrary, vitamin D resistance is an obstacle that indicates profound biological dysfunction, to be rectified only by means of an extremely aggressive and therefore dangerous therapy. The therapy thus serves to reveal the severity of the dysfunction, thereby leading inevitably to conceptual innovation. This sheds light on the theoretical innovations of which the therapeutic activity is capable.Therapeutic activity is also influenced by notions of health and illness, normal and pathological states, none of which may be determined entirely objectively. For example, the term healing as used by Albright in the case of resistant rickets that he described may be discussed in this light.Nosology, or the classification of diseases, depends largely on the description of clinical syndromes, which are themselves mainly based on subjective elements (discomfort, disability, or the extent of a patient's suffering). The advent of pathological anatomy at the beginning of the nineteenth century disrupted classification by introducing the concept of localized anatomical lesions81-and, hence, an element of material objectivity \3- into nosology. Radiological examination further complicated matters by enabling the equivalent of an autopsy on living matter. Lastly, biological examination complicated nosology by showing that biological anomalies may exist in human beings without necessarily leading to a pathological condition. Medical thinking can choose to combine all these elements to describe a disease, but can also separate them and retain only a few, or a single one, according to requirements - as did Albright.The notion of biological and pathological individuality is fundamental to the development of medical thinking. Whatever its theoretical origin, medical thinking has since ancient times incorporated the idea that each individual reacts differently to the same treatment and his own specific pathological tendencies. I mentioned earlier that in the history of vitamin D-resistant rickets the notion of rachitic tendency reflected this type of thinking. After 1937, this history progressed by successively separating new individual entities, affecting smaller and smaller groups of individuals in each case. In other words, the need to understand and to define individual illness more closely required the development of new concepts and the construction of new individual categories of disease linking these concepts to older clinical, radiological, and biochemical elements. (shrink)

Due to the outbreak of COVID-19 many families experience the threat of the COVID-19. This study aims to explore the lived experiences, challenges, and coping mechanisms of COVID-19 Family Survivors. The study employed the Interpretative Phenomenological Analysis with ten (10) participants. Based on the findings, the following conclusions were drawn: (1) Most of the participants consulted health professionals for their medications and advised herbal medicines in boosting their immune system. (2) Family survivors had to make adaptations to their daily routines (...) and established stringent health standards in their homes, such as separating the parents' and children's rooms, using disposable utensils, and ensuring that every surface of their homes was clean. (3) They were able to meet their necessities due to the generosity of their neighbors. These people were helped financially by their employers, neighbors, churchmates, and loved ones. Similarly, the government offered a different forum for the COVID-19 Family survivors to receive help and assistance. (4) Despite the hardships they faced, COVID-19 family survivors did not lose hope that they would be cured of COVID-19. These people tried their hardest to maintain their health by eating good meals, sleeping early, obtaining enough sunlight in the morning, and carefully selecting the vitamins they took. (5) Finally, despite the difficult battle against COVID19, these individuals grew resilient by building their spiritual lives, exercising their faith, and being brave for the sake of their loved ones. (shrink)

We consider the evidence that RA†, the vitamin A metabolite, is involved in three fundamental aspects of the development of the CNS: (1) the stimulation of axon outgrowth in particular neuronal sub‐types; (2) the migration of the neural crest; and (3) the specification of rostrocaudal position in the developing CNS (forebrain, midbrain, hindbrain, spinal cord). The evidence we discuss involves RA‐induction of neurites in cell cultures and explants of neural tissue; the teratological effects of RA on the embryo's nervous (...) system; the observation that RA can be detected endogenously in the spinal cord; and the fact that the receptors and binding proteins for RA are expressed in precise domains and neuronal cell types within the nervous system. (shrink)

Light can kill the photoreceptors of the eye, not only very bright direct sunlight, but more moderate illumination if the light is present continuously. Recent experiments show that rod apoptosis can be triggered by strong and constant activation of transduction, and that death can be prevented if transduction is inhibited even though the eye is illuminated. Vitamin A deficiency and genetically inherited diseases, such as some forms of retinitis pigmentosa and Leber congenital amaurosis, appear to kill like this: transduction (...) is activated at a high rate and continuously, and this causes the rods to die. Why does transduction kill? Our best guess is that continuous activation produces a prolonged lowering of the Ca2+ concentration, which is also thought to kill neurons in tissue culture and during the development of the nervous system. To prevent death in constant light, rods have evolved protective mechanisms including modulation of channels and ion transport to keep the Ca2+ from going too low. Prolonged light exposure also causes migration of transduction proteins from one part of the cell to another and a reversible shortening of the rod outer segments, the part of the cell that contains the pigment rhodopsin. All of these mechanisms are at work in the normal eye to reduce transduction and prevent the Ca2+ concentration from dropping too low for too long a time. That most of us retain our vision our entire lives is a testament to their effectiveness. BioEssays 28: 344–354, 2006. © 2006 Wiley Periodicals, Inc. (shrink)

Recent evidence, from both epidemiological and animal experimental studies, suggest that the very first environment, the intrauterine, is extremely important in determining the future health of the individual. Genetic and ‘lifestyle’ factors impinge on, and can exacerbate, a ‘programming’ effect of an adverse fetal environment. In this review, we present compelling evidence to suggest that one of the major organs affected by an unfavourable prenatal environment is the kidney. Many of the factors that can affect fetal renal development (i.e. exposure (...) to excess glucocorticoids, insufficient vitamin A, protein/calorie malnutrition (in rats) and alterations in the intrarenal renin angiotensinogen system), also produce hypertension in the adult animal. When nephron number is compromised during kidney development, maladaptive functional changes occur and can lead, eventually, to hypertension and/or renal disease. Surprisingly, it is during the very earliest stages of kidney development that the vulnerability to these effects occurs. BioEssays 25:212–220, 2003. © 2003 Wiley Periodicals, Inc. (shrink)

Retinoic acid (RA), a derivative of vitamin A, is essential for normal mammalian development. Developmental abnormalities induced by RA excess and vitamin A deficiency are different even though they affect the same organ systems, and it is clear that there are intraembryonic tissue differences in the requirement for RA. The developmental functions of RA are mediated by its effects on gene expression. In the nucleus, two different forms of RA bind to and activate two families of nuclear receptors, (...) which themselves co‐operate in initiating the transcription of target genes. In this article I propose that the amount of RA reaching the nucleus in different embryonic tissues is modulated by a mechanism involving three cytoplasmic binding proteins for retinol (CRBP I) and retinoic acid (CRABP I and II). Abnormalities of craniofacial development resulting from exposure of early neural plate stage embryos to RA excess have been studied in some detail; their initial stages involve alteration of both morphological development and the segment‐specific pattern of gene expression in the early hindbrain and its derived neural crest. This system is ideal for studying the relationships between retinoic acid receptors, retinoid binding proteins, and the development of genetic and morphological pattern. (shrink)

In vertebrate development, the HOX genes act to specify cell identity along much of the anterior‐posterior axis of the embryonic central nervous system. In all vertebrates examined to date, the vitamin A metabolite retinoic acid is implicated in the patterning of the anterior posterior axis and the induction of HOX gene expression. Two recent papers have extended the study of retinoic acid induction of HOX genes to the closest relatives of the vertebrates, amphioxus and tunicates(1,2). In both these species, (...) exogenous retinoic acid is able to induce ectopic expression of HOX 1 genes in the anterior central nervous system. This suggests that retinoic acid control of anterior‐posterior axis formation and HOX induction is not specific to vertebrates. However, in the more distantly related echinoderms and arthropods, retinoic acid does not seem to act in the same way. Thus the role of retinoic acid in anterior‐posterior axis specification may be a chordate innovation, perhaps linked to the evolution of another chordate character, the dorsal neural tube. (shrink)

Secondary lymphoid organs form in utero through an inherited and well‐established developmental program. However, maternal non‐heritable features can have a major impact on the gene expression of the embryo, hence influencing the future health of the offspring. Recently, maternal retinoids were shown to regulate the formation of immune structures, shedding light on the role of maternal nutrition in the genetic signature of emergent immune cells. Here we highlight evidence showing how the maternal diet influences the establishment of the immune system, (...) and we also discuss how unbalanced maternal diets may set the response to infection and vaccination in the progeny. (shrink)

Albert (von) Szent-Györgyi started his studies on biological oxidation processes - which also resulted in the discovery of vitamin C, for which he received the Nobel Price in 1937 - in the Laboratory of Physiology of the University in Groningen in 1922-1926. These studies were later continued in Cambridge (UK) and Szeged (Hungary). When he had already received the invitation as well as the financial means to come and work in Cambridge, he still did experiments in Groningen to find (...) out whether the adrenal extract, isolated by him and later found to be a major source of vitamin C, contained the hormone essential for the survival of cats whose adrenals were removed. He was rather upset by the negative results of this experiment, judging by the recollections of a former student of his. This history constitutes an interesting example of the difference between serendipitous discovery and planned invention. (shrink)

A more provocative subject than “lying in politics” is difficult to imagine. Everybody, from the proverbial “Joe Sixpack” to ivory-tower philosophers, can wax eloquently on the subject, if only because easy-to-find, shocking examples abound. If moral outrage were judged an essential vitamin, then condemning dishonesty undoubtedly guarantees a daily megadose. Unfortunately, at least for those who crave self-indulgent outrage, the anti-lying case is less than 100 percent compelling. It is a quagmire of the first order, if only because those (...) who cherish frankness also usually confess to lying. Hannah Arendt once suggested that lies are a necessary and justifiable tool of the statesman's trade. Formulating damnation criteria invites mind-boggling paradoxes, and strident defenders of truth-telling, with scant exception, admit that falsehoods are “sometimes” permitted for “good” reasons. And what might be these “good reasons”? Who can say for sure? Centuries of erudite scholarship on this point might be encapsulated as “Lying to me is bad, but I can consent to deceiving others for noble purposes, as artfully decided by myself.”. (shrink)

A major programme of irrigated rice extension in the Middle Senegal River Valley has further limited the river’s natural flooding in the floodplain (Waalo), initially reduced by drought. We conducted a transdisciplinary (TD) and gendered study in the region to explore links between agricultural biodiversity and family diets using a social analysis of women’s practices. The results showed how rice expansion impacts local agrobiodiversity, diet quality and the cultural way of life. Disappearance of the singular agropastoral and fishing system of (...) the Senegal River Valley is profoundly modifying the landscape, limiting wooded riverine settings, and is undermining the traditional diversified flood-recession cropping system in the Waalo. This is causing an overconsumption of rice by reducing alternative food sources, such as sorghum, vegetables and animal products (fish, milk and meat). In particular, flood-recession sorghums are in danger of disappearing, yet they are more nutritious than rice and now sell for twice as much, or more. The way of life is being disrupted, notably sociabilities previously based on territorial complementarities, and women are disadvantaged in terms of recognition and added workload. Women’s groups have launched collective irrigated gardens, organic or not, only supported by the local NGO, but any surplus is hardly ever sold on the weekly markets in the neighbourhood. Moreover, this diet imbalance increases nutritional risk factors for health, such as vitamin and iron deficiencies, especially for women, hypertension and diabetes. We argue that, firstly, gendered TD experiences are relevant for documenting women’s activities in order for them to gain political support and, secondly, that targeting women’s care tasks gives more value and impact to TD research results. (shrink)

A Nobel Prize winner, Dr. Szent-Györgyi concerns himself with the underlying forces and conditions that have prevented the realization of the higher possibilities of the American Dream, and, by extension, of all mankind. He addresses himself especially to the youth of the world in his attempt to show how man, the more he progresses technologically, seems the more to regress psychologically and socially, until he resembles his primate ancestors in a state of high schizophrenia. The fundamental question asked by this (...) book is: Why is it that most of the scientific research that is done to elevate human life serves in the end to destroy it? That this phenomenon exists is unarguable. How to alter it is the problem the author tackles. He finds the possibility, indeed the instrument of our survival, in our youth. Dr. Szent-Györgyi calls upon youth the world over to organize and exercise their power to create a new world. He implores them not to waste their energies in petulance and frustration-the world is ripe for the radical changes needed for man's survival, and for youth to fritter away their opportunity would be to compound the tragedy and seal the fate of mankind. Born into the fourth generation of a noted family of scientists in Hungary, Albert Szent-Györgyi decided at an early age to devote his life to biological research. As a medical student he required international recognition for his studies in microscopic anatomy. The First World War, which he spent in the service of the Austro-Hungarian army, caused a break in his career. After the war he left his devastated country to work for ten years in various countries, notably Germany, Holland, England and the United States. He then returned to his native Hungary to help rebuild science there. In 1937, he won the Nobel Prize for his studies on metabolism and for the discovery of ascorbic acid (Vitamin C). He soon found himself in conflict with the growing movement of Nazism, was arrested, escaped, and was hunted for years by the secret service of Hitler. After World War II, disappointed by Soviet colonialism and the terrorist methods of Stalin, he left Hungary and found refuge at the Marine Biological Laboratory of Woods Hole, Massachusetts. (shrink)

Despite the practical knowledge throughout the nineteenth century that citrus fruit cured scurvy, and that rickets and beriberi were diseases caused by poor diet, it was not until 1901 that animal feeding experiments led one investigator to propose the existence of 'accessory food factors,' a lack of which was determined to be the cause of some illnesses (Hopkins, 1949. In Joseph Needham and E. Baldwin (eds.), Hopkins and Biochemistry, 1861-1947: Papers Concerning Sir Frederick Gowland Hopkins, O.M., P.R.S., with a Selection (...) of His Addresses and a Bibliography of His Publications. Cambridge: W. Heifer and Sons Ltd). The discovery of vitamins has long been considered as a delayed discovery. This delay has been attributed to the power of the germ theory in physiology at the time. While the germ theory and theories of autointoxication certainly played a role in delaying the discovery of vitamins, I argue further that it is important to consider the difference made to physiology by understanding the vitamins’ catalytic function. The profound difference made to physiology by the vitamins’ catalytic function suggests that a vitamin concept had previously been systematically inaccessible to researchers working within the conceptual framework of Bernardian physiology. (shrink)

A “functional food” is a food-based product that provides a demonstrable physiological benefit beyond its dietary or nutritional value. This class of foods for specific health uses are designed to assist in the prevention or treatment of disease, or to enhance and improve human capacities. They include products like vitamin-fortified grains, energy bars, low-fat or low-sodium foods, and sports drinks. Three sets of concerns about functional foods deserve attention. 1) Their health benefits are greatly exaggerated and, in many cases, (...) non-existent; practical questions remain about their efficacy. 2) Their medicinal properties blur the boundaries between food and drugs; public health questions remain about their appropriate use, distribution, and regulation. 3) Their proliferation is fueled by the food industry, not by the medical profession; political questions remain about the role of market forces that too often benefit producers more than consumers. (shrink)