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Query: UMLS:C0011849 (
diabetes
)
277,896
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
In summary, the vitamin pantothenic acid is an integral part of the acylation carriers, CoA and acyl carrier protein (ACP). The vitamin is readily available from diverse dietary sources, a fact which is underscored by the difficulty encountered in attempting to induce pantothenate deficiency. Although pantothenic acid deficiency has not been linked with any particular disease, deficiency of the vitamin results in generalized malaise clinically. In view of the fact that pantothenate is required for the synthesis of CoA, it is surprising that tissue CoA levels are not altered in pantothenate deficiency. This suggests that the cell is equipped to conserve its pantothenate content, possibly by a recycling mechanism for utilizing pantothenate obtained from degradation of pantothenate-containing molecules. Although the steps involved in the conversion of pantothenate to CoA have been characterized, much remains to be done to understand the regulation of CoA synthesis. In particular, in view of what is known about the in vitro regulation of pantothenate kinase, it is surprising that the enzyme is active in vivo, since factors that are known to inhibit the enzyme are present in excess of the concentrations known to inhibit the enzyme. Thus, other physiological regulatory factors (which are largely unknown) must counteract the effects of these inhibitors, since the pantothenate-to-CoA conversion is operative in vivo. Another step in the biosynthetic pathway that may be rate limiting is the conversion of 4'-phosphopantetheine (4'-PP) to dephospho-CoA, a step catalyzed by 4'-phosphopantetheine adenylyl-transferase. In mammalian systems, this step may occur in the mitochondria or in the cytosol. The teleological significance of these two pathways remains to be established, particularly since mitochondria are capable of transporting CoA from the cytosol. Altered homeostasis of CoA has been observed in diverse disease states including starvation,
diabetes
, alcoholism, Reye syndrome (RS), medium-chain acyl CoA dehydrogenase deficiency,
vitamin B12 deficiency
, and certain tumors. Hormones, such as glucocorticoids, insulin, and glucagon, as well as drugs, such as clofibrate, also affect tissue CoA levels. It is not known whether the abnormal metabolism observed in these conditions is the result of altered CoA metabolism or whether CoA levels change in response to hormonal or nonhormonal perturbations brought about in these conditions. In other words, a cause-effect relation remains to be elucidated. It is also not known whether the altered CoA metabolism (be it cause or result of abnormal metabolism) can be implicated in the manifestations of a disease. Besides CoA, pantothenic acid is also an integral part of the ACP molecule.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Pantothenic acid in health and disease. 174 61
Many patients suffer from
vitamin B12 deficiency
and are thus exposed to irreversible sequelae if diagnosis occurs at a late stage. This prospective study undertaken by eight practitioners over a period of 12 months concerns early diagnosis. Blood vitamin B12 levels were measured in 152 patients presenting macrocytosis detected by systematic MCV analysis at the time of a blood test, a neuropathy or a recent cognitive, affective and behavioural problem, and were found to be lowered (< or = 175 pmol/l) in 54 patients of whom 43 had undergone vitamin B12 test treatment for 6 months. Haematological, neurological and psychiatric evaluation was carried out before and after treatment, and a diagnosis of deficiency was recorded in 24 patients based on unequivocal response to therapy. Improvement was greatest haematologically in 12 patients, neurologically in 6 patients and psychiatrically in 6 other patients, with 4 patients showing a combination of all modes. These 24 patients (mean age 69 years) suffered from numerous pathologies which were liable to complicate diagnosis in some of them: neurological (46%), psychiatric (37%), chronic alcoholism (33%), folic acid deficiency (29%), and
diabetes
(17%). The only diagnostic element used as a criterion of deficiency was an extremely low level of vitamin B12 (< or = 75 pmol/l). Marked macrocytosis or a combination of haematological and neuropsychiatric signs are strong indicators, but only improvement under treatment allowed a diagnosis to be made in the majority of patients. Macrocytosis was, however, not present in 6 of the 12 neuropsychiatric patients. The study thus identified a high proportion of patients with
vitamin B12 deficiency
who additionally presented, in equal proportions, both haematological and neuropsychiatric symptoms. Neither the clinical examination nor the vitamin B12 level in general permit early diagnosis based on a high probability index and long-term follow-up. Simpler methods for early diagnosis are therefore needed.
...
PMID:[Vitamin B 12 deficiency: early diagnosis in ambulatory care medicine]. 985 89
Non-insulin-dependent diabetes mellitus (NIDDM) and hyperhomocysteinemia are both associated with premature vascular disease. We tested the hypothesis that homocysteine is associated with vascular disease and other diabetic complications in patients with NIDDM. The current investigation is a cross-sectional analysis of baseline variables for participants in the Appropriate Blood Pressure Control in
Diabetes
(ABCD) Trial. Men and women aged 40 to 74 years with NIDDM and a mean diastolic blood pressure (BP) of 80 mm Hg or higher were eligible. We measured serum levels of total homocysteine (tHcy), cystathionine, and methylmalonic acid (MMA) and correlated these values with clinical and other laboratory measures of the complications of
diabetes mellitus
in 452 subjects. tHcy was higher in males than in females and correlated with the duration of hypertension and systolic BP. tHcy was significantly correlated with MMA (r = .35, P < .0001) and cystathionine (r = .53, P < .0001) levels and inversely correlated with serum B12 (r = -.23, P < .0001) and folate (r = -.18, P < .0001). It was significantly correlated with serum creatinine (r = .28, P < .0001 for males and r = .39, P < .0001 for females) and inversely correlated with creatinine clearance (r = -.19, P < .005 for males and r = -.30, P < .0001 for females). tHcy was not increased in subjects with cardiovascular disease or retinopathy, but it was increased in those with neuropathy (10.3 v 9.3 micromol/L, P < .05) and macroalbuminuria (11.0 v 9.2 micromol/L, P < .005). Of these subjects, 2.2% met the criteria for
vitamin B12 deficiency
and 1% met the criteria for folate deficiency. We conclude that elevations of tHcy in this population appear to be the result of a combination of vitamin deficiency and decreased renal function and do not appear to be a predictor of cardiovascular disease.
...
PMID:Total homocysteine is associated with nephropathy in non-insulin-dependent diabetes mellitus. 1048 47
Hyperhomocysteinemia is the result of a disturbed methionine metabolism. It results from enzyme and/or vitamin deficiency. Epidemiological studies have proven, that hyperhomocysteinemia is a risk factor for atherosclerotic cardiovascular diseases, stroke, peripheral arterial occlusive disease and venous thrombosis. Conflicting results come from prospective studies. Trials which are now in progress may clarify the "causality" of high homocysteine concentrations and will assess the value of homocysteine-lowering therapy. The induction of the atherogenic process by hyperhomocysteinemia seems to be associated with an alteration of endothelial and smooth muscle cell function leading to an accelerated formation of reactive oxygen species. An increased endothelial expression of adhesion molecules will then lead to an enhanced deposition of oxidized LDL in the vessel wall with the formation of foam cells. Additionally, hyperhomocysteinemia interferes with the coagulation system and thus also has prothrombotic effects. There is a high prevalence of hyperhomocysteinemia as a sign of a vitamin deficiency in elderly subjects which strongly increases with age. Elderly people have a high frequency of
vitamin B12 deficiency
which can be diagnosed more reliably by the measurement of serum methylmalonic acid (MMA) level than by serum vitamin B12. Subjects following a strict vegetarian diet also have a high prevalence of hyperhomocysteinemia caused by functional
vitamin B12 deficiency
(increased MMA level). Last but not least, hyperhomocysteinemia is a factor in the pathogenesis of neural tube defects and pre-eclampsia. An early diagnosis of
vitamin B12 deficiency
is important for the prevention of neurological damages. Homocysteine should be measured in patients with a history of atherothrombotic vessel diseases, in patients with
diabetes
or hyperlipidemia, in renal patients, in obese subjects, in elderly people, in postmenopausal women, and in early pregnancy. A specific diagnosis of an underlying vitamin deficiency is important for adequate treatment. Individuals with homocysteine level >12 micromol/l should increase and/or supplement their dietary intake of vitamins.
...
PMID:The importance of hyperhomocysteinemia as a risk factor for diseases: an overview. 1159 31
Orthostatic hypotension in patients with cobalamin (Cbl) deficiency has been reported previously in isolated cases but we are not aware of detailed systematic studies of hemodynamic and autonomic nervous system function in patients with cobalamin deficiency. We investigated hemodynamic and autonomic responses to 60 degrees passive head up tilt (HUT) in 21 patients with
vitamin B12 deficiency
, 21 healthy age-matched control subjects and 9 age-matched patients with
diabetes mellitus
(DM) and established diabetic neuropathy. To systematically assess hemodynamic and autonomic nervous system function, we performed measurements of heart rate, beat-to-beat systolic and diastolic blood pressure, stroke index, cardiac index, total peripheral resistance index, total power, low (LF) and high (HF) frequency oscillatory component of heart rate variability, LF/HF ratio and spontaneous baroreflex sensitivity. As compared to controls, we found a significant fall of systolic blood pressure during 60 consecutive beats directly after head up tilt; furthermore, a significantly blunted fall of stroke index, cardiac index and a lack of increase of total peripheral resistance index for the duration of tilt in patients with
diabetes mellitus
and in patients with
vitamin B12 deficiency
. As compared to controls, we observed an altered response of spectral indices of sympathetic activation and vagal withdrawal and an impaired modulation of baroreflex sensitivity during head up tilt suggestive of a complex modification in the neural control activities in patients with cobalamin deficiency, which was comparable to that observed in patients with
diabetes mellitus
and established autonomic neuropathy. The results suggest that
vitamin B12 deficiency
causes autonomic dysfunction with similar hemodynamic consequences and patterns of autonomic failure as seen in diabetic autonomic neuropathy. Defective sympathetic activation may be the cause for orthostatic hypotension, which is occasionally seen in patients with
vitamin B12 deficiency
. It is concluded that patients with orthostatic hypotension should be screened for cobalamin deficiency.
...
PMID:Autonomic dysfunction and hemodynamics in vitamin B12 deficiency. 1203 86
The recent development of acetylcholinesterase inhibitors to treat patients with Alzheimer's disease has increased interest in the use of biochemical markers for the early detection and diagnosis of dementia, but only the measurement of the protein 14-3-3 in cerebrospinal fluid (CSF) to help diagnose sporadic Creutzfeldt-Jakob disease has become accepted clinical practice. CSF concentrations of tau protein and beta-amyloid peptide 42 have been widely investigated as potential diagnostic tests for Alzheimer's disease, but neither has shown sufficient sensitivity and specificity for clinical use. Preliminary investigations suggest that beta-amyloid peptide 42 may be useful in monitoring disease progression, but this needs to be verified. In addition, biochemical investigations may help to identify the small number of patients with treatable causes of dementia such as hypothyroidism and
vitamin B12 deficiency
, as well as any other compounding condition such as anaemia or
diabetes mellitus
that increase morbidity.
...
PMID:Biochemical investigations in patients with dementia. 1203 95
Hyperhomocysteinemia (HHCY) is a consequence of disturbed methionine metabolism. It results from enzyme and/or vitamin deficiency. Epidemiological and clinical studies have proven HHCY to be an independent risk factor for atherosclerotic cardiovascular diseases, stroke, peripheral arterial occlusive disease and venous thrombosis. Trials in progress may clarify the "causality" of high homocysteine (HCY) concentrations and will assess the value of HCY lowering therapy. HHCY is also seen as a risk factor for neurodegenerative diseases such as cognitive impairment, dementia, Alzheimer's disease, and also for depression. There is a high prevalence of HHCY as a syndrome of vitamin shortage in elderly subjects, which strongly increases with advancing age. Elderly people have a high frequency of
vitamin B12 deficiency
which is more reliably diagnosed by measurement of serum methylmalonic acid and holotranscobalamin II, the metabolically active B12 fraction, than by total serum vitamin B12. Subjects who follow a strict vegetarian diet also have a high prevalence of HHCY caused by
vitamin B12 deficiency
. For prevention of neurological damages an early diagnosis of
vitamin B12 deficiency
is important. Furthermore, HHCY is a factor in the pathogenesis of neural tube defects and preeclampsia. HCY should be measured in patients with a history of atherothrombotic vessel diseases, in patients with
diabetes
or hyperlipidemia, in renal patients, in adipose subjects, in elderly people, in vegetarians, in postmenopausal women, and in early pregnancy.
...
PMID:Hyperhomocysteinemia: a new risk factor for degenerative diseases. 1238 6
Psychiatric manifestations are frequently associated with pernicious anemia including depression, mania, psychosis, dementia. We report a case of a patient with
vitamin B12 deficiency
, who has presented severe depression with delusion and Capgras' syndrome, delusion with lability of mood and hypomania successively, during a period of two Months. Case report - Mme V., a 64-Year-old woman, was admitted to the hospital because of confusion. She had no history of psychiatric problems. She had history of
diabetes
, hypertension and femoral prosthesis. The red blood count revealed a normocytosis with anemia (hemoglobin=11,4 g/dl). At admission she was uncooperative, disoriented in time and presented memory and attention impairment and sleep disorders. She seemed sad and older than her real age. Facial expression and spontaneous movements were reduced, her speech and movements were very slow. She had depressed mood, guilt complex, incurability and devaluation impressions. She had a Capgras' syndrome and delusion of persecution. Her neurologic examination, cerebral scanner and EEG were postponed because of uncooperation. Further investigations confirmed anemia (hemoglobin=11,4 g/dl) and revealed
vitamin B12 deficiency
(52 pmol/l) and normal folate level. Antibodies to parietal cells were positive in the serum and antibodies to intrinsic factor were negative. An iron deficiency was associated (serum iron=7 micromol/l; serum ferritin concentration=24 mg/l; serum transferrin concentration=3,16 g/l). This association explained normocytocis anemia. Thyroid function, hepatic and renal tests, glycemia, TP, TCA, VS, VDRL-TPHA were normal. Vitamin B12 replacement therapy was started with hydroxycobalamin 1 000 ng/day im for 10 days and iron replacement therapy. Her mental state improved dramatically within a few days. After one week of treatment the only remaining symptoms were lability of mood, delusion of persecution, Capgras' syndrome but disappeared totally 9 days after the beginning of the treatment. A neurologic examination was possible because of cooperation. All the tendon reflexes of inferior members were absent. The plantars were in flexion and there was a left inferior member hypoesthesia. The cerebral scan and EEG were normal. Fundic biopsy, realized by fibroscopy, revealed fundic atrophia and intestinal metaplasia compatible with Biermers' disease. The iron deficiency exploration concluded diet deficiency. Mme V. appeared euphoric, her speech was very rapid with play on words and overactivity. This hypomania state totally disappeared 3 days after. Six Months after her hospitalisation, she presented an hypothyroidism (TSH=3,780; T3=1,35; T4=1,08). A thyroid hormones replacement was started and she continued to receive Monthly B12 replacement. Discussion - This case report illustrates psychiatric manifestations of Biermers' disease. The clinical arguments in favour are: white woman, more than 60 Years old, no history of psychiatric problems, atypical symptoms (confusional state with psychiatric symptoms), fluctuation of symptoms (severe depression with confusional state, delusion of persecution and Capgras' syndrome; delusion with lability of mood and hypomania), dramatic improvement after 9 days of vitamin B12 replacement therapy. The biological arguments are: anemia,
vitamin B12 deficiency
, normal folate level, atrophia and fundic metaplasia, positive antibodies to parietal cells in the serum, association between Biermers' disease and autoimmune disease (Haschimoto thyroidite). Psychiatric manifestations can occur in the presence of low serum B12 levels but in the absence of the other well recognized neurological and haematological abnormalities of pernicious anemia. Mental or psychological changes may precede haematological signs by Months or Years. They can be the initial symptoms or the only ones. Verbank et al. described the case of a patient with
vitamin B12 deficiency
in whom hypomania, paranoia and depression had been successively presented during a period of 5 Years before anemia have been developed. The case of Mme V. is similar in the succession of severe depression with delusion of persecution and Capgras' syndrome, delusion with lability of mood and hypomania, during a period of two Months. This report seems to be the first one of a sequence of several psychiatric states with pernicious anemia during a period of two Months with normocytosis anemia. To illustrate this illness we reviewed the literature regarding psychopathology associated with B12 deficiency. The most common psychiatric symptoms were depression, mania, psychotic symptoms, cognitive impairment and obsessive compulsive disorder. The neuropsychiatric severity by
vitamin B12 deficiency
and the therapeutic efficacy depends on the duration of signs and symptoms. Conclusion - We recommend consideration of B12 deficiency and serum B12 determinations in all the patients with organic mental disorders, atypical psychiatric symptoms and fluctuation of symptomatology. B12 levels should be evaluated with treatment resistant depressive disorders, dementia, psychosis or risk factors for malnutrition such as alcoholism or advancing age associated with neurological symptoms, anemia, malabsorption, gastrointestinal surgery, parasite infestation or strict vegetarian diet. In first intention, B12 deficiency should be researched by serum B12 determination (normal 200-950 pg/ml). Studies of methylmalonic acid and homocysteine showed that they are very sensitive functional indicators of cobalamin status especially when other evidence of cobalamin (B12) deficiency was equivocal. Measurement of methylmalonic acid (normal 73-271 nmol/l) and homocysteine (normal 5,4-13,9 micromol/l) should not replace the measurement of serum cobalamin.
...
PMID:[Psychiatric manifestations of vitamin B12 deficiency: a case report]. 1502 91
A case of peripheral neuropathy in a patient with
diabetes
who had atypical clinical findings is presented. Because of the atypical initial manifestations and short duration of insulin-dependent
diabetes
, another cause of the neuropathy was suspected. The presence of vitiligo, hypothyroidism, and
diabetes
prompted a search for evidence of pernicious anemia. Despite a normal blood cell count, the diagnosis of pernicious anemia was confirmed on the basis of an increased serum gastrin level and antiparietal cell antibody titer. Treatment with vitamin B12 resulted in an arrest, but not a reversal, of the signs of peripheral neuropathy. In patients with
diabetes
,
vitamin B12 deficiency
should be suspected; its early diagnosis and treatment are important in minimizing neurologic damage.
...
PMID:Nondiabetic neuropathy in a patient with diabetes. 1525 65
A study was designed to generate epidemiological and clinical data on dementia, in a teaching hospital in India. It was conducted on 124 (94 male and 30 female) elderly patients (aged more than 60 years) presenting with clinical syndrome of dementia (DSM-3). Their age range was 64-78 (mean 65.7 4.1) years. Detailed clinical, biochemical, radiological and electrophysiological evaluation was done to establish etiology. Patients with psychiatric ailments, cranial trauma and tumors were excluded. The study period was 4.2 years. Multi-infarct dementia (MID) was observed to be commonest cause of dementia and was present in 59 (47.6%) cases. There were 10 (8%) patients each of tuberculosis (TB) and neurocysticercosis (NCC). Alcohol-related dementia was present in 13 (10.5%), while malnutrition (
Vitamin B12 deficiency
) was present in 9 (7.2%). Alzheimer's Disease (AD) was present (NINCDS-ADRDA criteria) in 6 patients (4.8%). There were 3 (2.4%) cases 1 each of Huntington's disease, Parkinson's and Normal Pressure Hydrocephalus and 2 each of
diabetes
, hypothyroidism, hyperthyroidism and Creutzfeldt' Jakob Disease. We conclude that AD, which is irreversible and common in the west, is relatively uncommon in India as compared to MID, infections and malnutrition, which are potentially treatable.
...
PMID:Some observations on the spectrum of dementia. 1526 74
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