Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “AVITAMINOSIS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,045 records · Page 58Linked to original sources

Neural-tube defects and vitamins: the need for a randomized clinical trial.

It has been suggested that taking extra vitamins around the time of conception may reduce the risk of fetal neural-tube defects. We have examined the evidence for this and conclude that there is considerable doubt about the efficacy of such a regimen. Also, it cannot be assumed that the taking of extra vitamins has no adverse medical effects. We give reasons for our view that a large randomized clinical trial is ethical and the only satisfactory way of resolving the matter. The Medical Research Council is currently conducting such a study in centres in Britain and abroad, involving women who have already had a pregnancy with a fetal neural-tube defect. The design of the Medical Research Council study is described briefly.

Anencephaly↗

Hyperhomocysteinaemia in chronic liver diseases: role of disease stage, vitamin status and methylenetetrahydrofolate reductase genetics.

BACKGROUND/AIMS: The liver plays a key role in sulphur aminoacid metabolism hence, homocysteine metabolism may be impaired in chronic liver diseases. The aim of this study was to investigate, in patients affected by chronic liver diseases, (1) the prevalence of hyperhomocysteinaemia and (2) the role of its determinants such as the stage and the aetiology of disease, vitamin status, genetic documented alterations (methylenetetrahydrofolate reductase deficiency) and presence/absence of documented malignant evolution (hepatocellular carcinoma). MATERIAL AND METHODS: One hundred and thirty patients with chronic liver disease (34 with chronic active hepatitis, 12 with fatty liver and 88 with liver cirrhosis) and 50 healthy age-matched control subjects were included into the study. RESULTS: Hyperhomocysteinaemia was defined as homocysteine plasma levels greater than 12.6 micromol/l. Hyperhomocysteinaemia prevalence in liver cirrhosis group was 40.9%, significantly higher (all P<0.01) with respect to controls (12%), chronic active hepatitis (14.7%) and fatty liver (25%) groups and increased with Child-Pugh stage [Child A: 22.2%, Child B (50%); Child C (58.3%)]. In chronic-active hepatitis and liver cirrhosis, the prevalence of subjects with methylenetetrahydrofolate reductase C677-->T mutation (both as CT and as TT) and hyperhomocysteinaemia results in significantly higher levels with respect to controls. Methylenetetrahydrofolate reductase C677-->T mutation and disease stage showed to be the most important predictive factors of hyperhomocysteinaemia in liver cirrhosis whereas the influence of homocysteine-related vitamin status seems to have a secondary role. CONCLUSIONS: In conclusion hyperhomocysteinaemia is highly prevalent in liver cirrhosis but not in other chronic liver diseases; it may contribute to fibrogenesis and vascular complication of liver cirrhosis.

Avitaminosis↗

Managing erythropoietin hyporesponsiveness.

The anemia of chronic kidney disease is associated with cardiovascular disease, decreased quality of life, and mortality. The introduction of recombinant human erythropoietin (rHuEPO) has transformed the management of this condition. However, a significant proportion of patients fail to respond to even high doses of rHuEPO. Several factors have been implicated in the hyporesponsiveness to rHuEPO. Iron deficiency, whether absolute or functional, is considered the most important, and maintenance of adequate iron stores reduces rHuEPO requirements among patients on hemodialysis. However, traditional indices of iron that are currently utilized may not reflect iron stores accurately, and there is also increasing concern regarding the potential long-term toxicity of parenteral iron therapy. Infection and inflammation also influence the response to rHuEPO, both by disruption of iron metabolism and by eliciting the release of cytokines that inhibit erythropoiesis. Oxidative stress may contribute to rHuEPO hyporesponsiveness directly by promoting lipid peroxidation in cell membranes, leading to increased erythrocyte fragility and reduced life span and also through its strong association with inflammation. Severe hyperparathyroidism can lead to a reduced number of erythroid progenitor cells. Inadequate dialysis dose, aluminum overload, nutritional factors such as deficiencies of carnitine, vitamin B12, folic acid, and vitamin C can also reduce the efficacy of rHuEPO therapy. Hyporesponsiveness to rHuEPO presents a challenge to both diagnosis and management in an era where optimizing response to rHuEPO is critical both in limiting the burgeoning costs of anemia management and improving clinical outcomes in the dialysis population.

Aluminum↗

Mechanisms of vitamin deficiencies in alcoholism.

Chronic alcoholic patients are frequently deficient in one or more vitamins. The deficiencies commonly involve folate, vitamin B6, thiamine, and vitamin A. Although inadequate dietary intake is a major cause of the vitamin deficiency, other possible mechanisms may also be involved. Alcoholism can affect the absorption, storage, metabolism, and activation of many of these vitamins. Possible factors which cause alterations in the absorption, storage, and metabolism of these vitamins are discussed. Suggestions for management of vitamin deficiencies in chronic alcoholics are also discussed.

Alcoholism↗

Appropriateness of vitamin and mineral prescription orders for residents of health related facilities.

A study was made of the medical charts of 433 elderly patients admitted to four Health Related Facilities in upper New York State, to determine whether the respective prescription orders for vitamins and minerals were appropriate to the given diagnoses and, if not, identify the variables correlated with inappropriateness. For 11.1 percent of the patients, vitamins or minerals were prescribed when there was no specific diagnostic indication, or they were not prescribed when the medical diagnosis indicated that they should have been. Women and medicaid patients were more likely than men and self-paying patients to be treated inappropriately with respect to vitamins and minerals, but the differences were not satistically significant.

Aged↗

Oral versus intramuscular vitamin supplementation for hypovitaminosis in the elderly.

Thiamin, folate, biotin, riboflavin, nicotinates, pantothenate, carotenes, and vitamins B6, B12, A, E and C were measured in the blood of 228 elderly ambulatory residents of a nursing home. Their mean age was 87 years (range, 60-102). None had undergone major surgical procedures; their diet was good, and each had received at least one multivitamin pill every day for 3 to 5 months before the study. A comparison group of 204 healthy volunteers, aged 20-50 was also studied. Of the 228 elderly subjects, 88 (39 percent) showed vitamin deficits despite oral vitamin supplementation. Single and multiple deficits of vitamin B6, nicotinate, vitamin B12, folate, and thiamin were found. Three months after a single intramuscular injection of multivitamins (with no other vitamin supplementation), these deficits were no longer detectable in the blood of 89-100 percent of the vitamin-deficient elderly. Intramuscular rather than oral vitamin supplementation is a more effective method for maintaining adequate blood levels of vitamins in the elderly; the intramuscualr route apparently promotes saturation of tissue stores with enough vitamins to meet the needs, and thus obviates problems of vitamin malabsorption possibly due to drug interference or small-bowel atrophy.

Administration, Oral↗

Effects of diet and nutrition on drug therapy.

Foods containing biochemically active substances have been used therapeutically throughout the ages and continue to function as important adjuncts to drug therapy. But naturally-occurring substances can also have adverse effects, as can the food additives of today. Food--drug interactions can alter the effect of therapeutic agents or cause adverse reactions where none had existed. These problems are often aggravated in elderly patients, who may suffer from malnutrition (e.g., protein insufficiency) or altered food metabolism. Malnutrition in the elderly can be caused by disease, socioeconomic factors, or simply by the deterioration of eating habits. Although nutritional requirements decrease with age, the elderly still need nutrients for the repair of normal structures and for energy. The nutritional needs of the elderly remain poorly defined. Drugs can alter food metabolism, which, in turn, can affect drug action. Many food--drug interactions are well documented; drug absorption and drug elimination are often affected by an altered food metabolism. Particular problems include salicylate-induced iron deficiency, poor monitoring of vitamin metabolism and the effects of vitamin underuse and overuse, and lack of knowledge about the effects of long-term drug use on vitamin metabolism. An additional problem is the presence of potentially harmful materials in non-prescription products.

Aged↗

Circulating vitamins in Alzheimer's dementia as compared with other dementias.

Blood levels of 12 vitamins were compared in 55 patients with Alzheimer's disease and 58 control subjects (10 intellectually alert, 12 depressed, 28 multi-infarct dementias, 8 with other specific dementias). No significant differences in vitamin blood levels were found between the Alzheimer's disease group and the control groups either individually or in total. Conventional parenteral vitamin treatment of seven patients with vitamin deficits did not benefit their cognitive state. Conventional vitamin malnutrition did not seem to contribute to the disability in these subjects.

Aged↗

Discordant microform cleft lip in a dizygotic female twin.

Details are given regarding a pair of dizygotic twins, discordant for microform cleft lip. The maternal history is reviewed, indicating three environmental factors as relevant to the origin of the cleft, using the multifactoral threshold model. Nurses are encouraged to survey and report cases concerning microform cleft lip.

Adult↗

Myopathy and neuropathy associated with osteomalacia.

Thirty unselected females with proven osteomalacia were evaluated clinically, electromyographically and histopathologically for muscle dysfunction. Clinical evidence of myopathy was found in all the patients except one; the electromyograms were abnormal in 25 of them, and histopathological abnormalities, although slight and nonspecific, were seen in all the 17 patients who underwent muscle biopsy. Electromyographic findings revealed a myopathic pattern as evidenced by a significant reduction in motor unit potential duration and amplitude, and an increased percentage polyphasicity as compared to the controls. There was a complete absence of denervation potentials. The histopathological abnormalities were nonspecific and slight, and consisted of fatty infiltration, interstitial fibrosis, sarcolemmal nuclear proliferation and variation in muscle fibre thickness. A statistically significant reduction in motor nerve conduction velocities of the ulnar and peroneal nerves was found. It was considered that this reduction in the velocities was due to subclinical neuropathy. Our data suggest that myopathy, neuropathy and osteomalacia in our patients are due to nutritional deficiencies of multiple vitamins.

Abortion, Spontaneous↗