vitamin-b-12 and Hyperplasia

Topics: Anemia, Hemolytic; Anemia, Hypochromic; Anemia, Megaloblastic; Arthritis, Juvenile; Arthritis, Rheumatoid; Blood Volume; Collagen Diseases; Dermatomyositis; Felty Syndrome; Folic Acid; Hemolysis; Humans; Hyperplasia; Iron; Lupus Erythematosus, Systemic; Myositis; Polyarteritis Nodosa; Polymyalgia Rheumatica; Scleroderma, Systemic; Vitamin B 12

Vitamin deficiency may be related to carcinogenesis. Cytologic examinations of sputum have already found that the administration of folate and vitamin B12 suppressed the development of squamous metaplasia and atypia in smokers' airways. The authors investigated the effect of folic acid, vitamin B12, and vitamin A on the formation of metaplasia and hyperplasia in methylcholanthrene (MCA)-treated rats.. The SD strain of rats received 10 mg of MCA intratracheally and was divided into six groups as follows: (1) vitamin A; (2) folic acid; (3) vitamin B12; (4) vitamin B12 with folic acid; (5) a combination of vitamin A, folic acid, and vitamin B12; and (6) no vitamins. The Lower respiratory tract epithelia of the rats were examined histologically 20, 32, and 36 weeks after MCA administration and at the end of the experiment.. A clear difference was detected between the group receiving folic acid and that receiving vitamin A. In the former group, metaplasia was found in only one rat, atypia was not found, and hyperplasia with marked changes was present in less than 50% of other groups. In the latter group, atypia was found in all of the metaplastic foci.. It was suggested that the epithelial hyperplasia and metaplasia of respiratory tract induced by MCA can be suppressed by the administration of folic acid.

Topics: Animals; Body Weight; Bronchi; Epithelium; Folic Acid; Hyperplasia; Metaplasia; Methylcholanthrene; Rats; Rats, Sprague-Dawley; Vitamin A; Vitamin B 12

Topics: Anemia, Megaloblastic; Bone Marrow; Erythroid Precursor Cells; Female; Folic Acid; Hematopoietic Stem Cells; Humans; Hyperplasia; Middle Aged; Pancytopenia; Transcobalamins; Vitamin B 12

Preneoplastic changes in organ cultures of mouse embryonic kidney (OCEK) under transplacental N-nitrosoethyl urea (ENU) did not increase under the influence of Ado-Cbl. The frequency of focal proliferation in OCEK under transplacental influence of Ado-C bl and ENU was 2.2 times less than the combination of carcinogen with MeCbl (32.2% and 71.9%, respectively, P less than 0.01). The number of DNA-synthesising epithelial cells in OCEK were less under transplacental influence of Ado-Cbl (8.6 +/- 1.4%) than in MeCbl or FA (19.4 +/- 1.8% and 16.2 +/- 1.3% respectively, P less than 0.01).

Topics: Animals; Cobamides; Epithelium; Ethylnitrosourea; Female; Hyperplasia; Kidney; Leucovorin; Mice; Organ Culture Techniques; Placenta; Pregnancy; Time Factors; Vitamin B 12

Topics: Adolescent; Biomarkers, Tumor; Biopsy; Carcinoma, Hepatocellular; Humans; Hyperplasia; Liver; Liver Neoplasms; Male; Neurotensin; Tomography, X-Ray Computed; Vitamin B 12

Small intestinal absorptive function was investigated in six patients with the acquired immunodeficiency syndrome (AIDS) who had diarrhoea and weight loss. Proximal function was assessed by [14C]Triolein test of fat absorption. Distal function was determined by a test of bile acid absorption in which the loss of radio-labelled synthetic bile acid, 75seleno-23-homocholic acid-taurine ([75Se]HCAT), from the enterohepatic circulation was quantified by abdominal gamma-scanning and by a vitamin B12-intrinsic factor absorption test. Concurrently indirect tests of small intestinal bacterial overgrowth ([14C]glycocholate and breath hydrogen) were carried out. In addition, jejunal histological examination and stool microscopy and culture for enteropathogens were performed. Fat absorption was reduced in all six patients, four of whom had jejunal villous atrophy. Bile acid and vitamin B12 absorption were normal in four subjects. Enteropathogens were not detected in any of the four subjects with normal terminal ileal absorptive function. In contrast, reduced bile acid and vitamin B12 absorption were detected in two of six subjects. Both patients had an enteropathogen (Cryptosporidium spp. and Isospora belli) present on stool and jejunal histological examination. Neither subject had evidence of small-intestinal bacterial overgrowth. AIDS patients therefore may have normal ileal absorptive function in the presence of jejunal disease. Infection with Cryptosporidium spp. or I. belli may however, be associated with severe ileal dysfunction.

Topics: Acquired Immunodeficiency Syndrome; Adult; Atrophy; Cryptosporidiosis; Dietary Fats; Female; Humans; Hyperplasia; Ileal Diseases; Intestinal Absorption; Jejunal Diseases; Malabsorption Syndromes; Male; Middle Aged; Vitamin B 12; Weight Loss

Transplacental growth-stimulating effect of the Cbl-coenzyme methylcobalamine (MeCbl) was revealed in organ cultures of embryonic kidney tissue in DBA/2 mice. MeCbl improved the survival of embryonic kidney explants and decreased the incidence of degenerative damage in cultures. The frequency of regeneration development was 30%. Hyperplastic epithelial changes were much more marked after transplacental MeCbl administration (71.8%), than in the control (9.0%).

Topics: Animals; Female; Hyperplasia; Kidney; Mice; Mice, Inbred DBA; Organ Culture Techniques; Placenta; Pregnancy; Vitamin B 12

The influence of dietary protein content and dietary vitamin B12 supplement on the hepatotoxicity and carcinogenicity of aflatoxin in rat liver was studied. In animals fed a low-protein diet, aflatoxin induced extensive toxic and carcinogenic effects. Cirrhosis was significantly prevented to a certain level by vitamin B12 administration, but the incidence of cholangiofibrosis and hyperplastic nodules was unchanged. No toxic effect was observed in animals receiving high-protein diet with no vitamin B12 supplement in this study (33 weeks). Only one rat bearing a hepatoma was observed in this group. However, hepatoma and hyperplastic nodules were found in the group receiving high-protein diet plus vitamin B12. Cholangiofibrosis and cirrhosis were not observed in the high-protein group regardless of vitamin B12 administration.

Topics: Aflatoxins; Animals; Carcinoma, Hepatocellular; Dietary Proteins; Hyperplasia; Liver; Liver Cirrhosis, Experimental; Liver Neoplasms; Male; Neoplasms, Experimental; Rats; Vitamin B 12

Topics: Adenoma, Islet Cell; Bicarbonates; Celiac Disease; Diarrhea; Duodenum; Feces; Female; Gastric Juice; Humans; Hyperplasia; Hypokalemia; Intestinal Secretions; Malabsorption Syndromes; Middle Aged; Pancreas; Pancreatic Neoplasms; Pancreatitis; Potassium; Precancerous Conditions; Vitamin B 12

Topics: Aged; Anemia, Sideroblastic; Ascorbic Acid; Autopsy; Blood Cell Count; Blood Transfusion; Bone Marrow; Bone Marrow Cells; Bone Marrow Examination; Erythrocytes; Erythropoiesis; Folic Acid; Follow-Up Studies; Humans; Hyperplasia; Iron; Leukemia, Myeloid; Male; Middle Aged; Monocytes; Muramidase; Precancerous Conditions; Pyridoxine; Vitamin B 12

Topics: Aflatoxins; Animals; Autoradiography; Body Weight; Choline; Diet; DNA; Hyperplasia; Kidney; Lipids; Lipotropic Agents; Liver; Liver Neoplasms; Male; Methionine; Rats; Thymidine; Tritium; Vitamin B 12

Topics: Amino Acids; Animals; Avian Sarcoma Viruses; Chick Embryo; Chickens; Chorioallantoic Membrane; Enzymes; Extraembryonic Membranes; Fowlpox virus; Glycine; Hyperplasia; Hypertrophy; Liver; Neoplasms; Poxviridae; Proteins; Research; Rous sarcoma virus; Sarcoma, Avian; Vitamin B 12