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Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A study was undertaken to ascertain whether vitamin D has a direct action on the mineralization of the dentin in rats made rachitic by a diet low in calcium and deficient in vitamin D. Physiological amounts of vitamin D, given orally to rachitic rats, increased their serum calcium from 4.8±0.5 mg/100 ml to 7.5±0.4 mg/100ml. The mineralization of dentin recovered markedly, although osteoporosis occurred in bone trabeculae. The results suggest that vitamin D increases serum calcium by accelerating bone resorption and that the increased serum calcium level acts directly to mineralize the dentin. When calcium was given to rachitic rats by subcutaneous injection, the serum calcium level increased and mineralization of dentin recovered to the same extent as that observed in rats given vitamin D. These results indicate that recovery of mineralization of rachitic dentin depends primarily on recovery of the serum calcium level and that vitamin D is an indirect factor in the mineralization process. [ABSTRACT FROM AUTHOR]

A series of analogues of vitamin D have been tested for their ability to stimulate bone resorption in two test systems used previously to investigate the metabolites of vitamine D. These analogues were tested (a) by directly comparing their action on bone explants of mouse half-calvaria in vitro, and (b) by injecting them into young mice and measuring the degree of resorption in vitro when explants were prepared 18 hours after the injection. It is concluded that the key functional groups concerned with enhancing the activity of vitamin D are the 1α- and the 25-hydroxyl, both together; the cis ring structure for ring A appears necessary. 1α-Hydroxycholecalciferol (1α-OHD) is about as active as 25-OHD in the direct test, but its potency is much nearer to that of 1,25-(OH)D when tested by the second (indirect) method; it seems likely that 1α-OHD is converted into 1,25-(OH)D in vivo. The results are discussed in relation to the designing of analogues for clinical and experimental use. [ABSTRACT FROM AUTHOR]

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Klinische Wochenschrift is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article discusses developments in vitamin D research. Evidence that this activated sterol has an important role not only as a vitamin or nutritional supplement but also as a hormone that interacts with other calcium-regulative hormones, such as parathyroid hormone, to maintain mineral homeostasis. Two developments that illustrate this are the characterization of the stages of vitamin D deficiency and advances in the knowledge of the intermediary metabolism of vitamin D. The lack of appropriate public health measures in developing countries and the peculiarities of local diets or local customs account for the continued prevalence of nutritional rickets in many countries. The importance of health education and of periodic examinations of high-risk populations is evident from the experience of physicians in Glasgow, who recognized a rise in the number of cases of rickets in spite of a government subsidy program to provide fortified milk.

According to the vitamin D hypothesis, demyelination in multiple sclerosis results from a breakdown of myelin due to abnormal lipid composition and structure, produced during the period of brain development. The observed abnormalities (altered lipid concentrations and fatty acid profiles are viewed as a consequence of deficiencies in enzymes that govern myelin lipid synthesis and membrane assembly. The enzyme deficiencies, genetic in origin, are proposed to occur because of inadequate supplies of vitamin D and calcium at times of rapid myelination and growth, mainly in adolescence. If the theory proves to be correct, it may be possible to suppress the disease by dietary supplementation with vitamin D and calcium during puberty. [ABSTRACT FROM AUTHOR]

A new theory for the etiology of multiple sclerosis (MS) has been developed which is compatible with epidemiologic, biochemical and genetic evidence. A predisposition for the disease is held to result from the development of abnormal myelin during puberty. Vitamin D and calcium are proposed as being essential for normal myelination. Curtailed supplies of these substances (from inadequate sunlight and phytate-rich diets) correlate with geographic regions diets) correlate with geographic regions of high risk of MS. Conversely the prevalence of MS is lower where vitamin D is abundant, as in sunny climates, high altitudes, and littorals with dietaries rich in fish oils. [ABSTRACT FROM AUTHOR]

The intrarenal blood flow (IRBF) distribution has been studied in dogs during acute and chronic calcium intoxication, using clearance technique,Kr disappearance curves, autoradiograms, and silicone rubber injections. The purpose of this study was to determine whether a modification of the IRBF could be responsible for the decrease of the cortico-medullary osmotic gradient and the hyposthenuria generally observed in these conditions. Acute hypercalcemia was produced in 12 dogs by infusing a solution of CaCl into the left renal artery. 20 min after starting infusion (PCa in renal vein = 7.34 mEq/l), the urinary osmolarity and the TcHO were slightly decreased on the experimental side ( P<0.05). C.PAH was also depressed ( P<0.005), while E.PAH remained constant. TheKr curves and the autoradiograms reflected a redistribution of IRBF toward the deeper region of the kidney. In 10 dogs chronically intoxicated with vitamin D, (PCa=6.68 mEq/l) the U.osm and TcHO were markedly depressed ( P<0.001). Renal tissue analysis showed a significant fall of the cortico-medullary osmotic gradient of Na. In parallel, a decrease in C.PAH was observed.Kr curves demonstrated a significant redistribution of IRBF with a decrease of the percent of initial radioactivity in the cortex. Autoradiograms and silicone rubber vascular casts also demonstrated a vasodilatation of the vasa recta of the medulla. These data therefore support the conclusion that a redistribution of IRBF contributes to the hyposthenuria observed during hypercalcemia. [ABSTRACT FROM AUTHOR]

Presents a study which evaluated the actions of 1,25 dihydroxy-vitamin D[sub3] in patients with advanced renal failure. Background on the therapeutic use of the vitamin; Clinical characteristics of the patients; Materials and methods used; Findings and discussion.

There is evidence that a derangement in vitamin D metabolism on the part of the mother, the fetus, or both may be responsible for supravalvular aortic stenosis, especially when the latter is associated with infantile hypercalcemia. It has been shown that the offspring of rabbits given large amounts of parenteral vitamin D throughout pregnancy may be born with aortic lesions resembling supravalvular aortic stenosis as seen in man. The present study was designed to explore experimentally the relationship between exposure to excessive amounts of vitamin D during pregnancy and the development of the craniofacial complex and dentition because children with the multiple system abnormalities of the supravalvular aortic stenosis syndrome (SASS) share a characteristic craniofacial appearance and exhibit, in common, many abnormalities of dentition. Examination of their jaws and teeth reveals hypoplasia of the mandible, congenital absence of teeth (usually the lateral incisors and second premolars of the maxilla), microdontia, dysgnathia, enamel hypoplasia, and a narrowed occlusal table. In the present study, analogous findings were observed in rabbit offspring whose mothers received large amounts of vitamin D during pregnancy. The most marked functional accompaniment of these abnormalities was severe malocclusion of the teeth. Peculiar facies, premature closure of the cranial bones, strabismus, odd shaped ears, and a low birth weight were additional features of SASS that were noted in many test animals. Buphthalmos was also noted occasionally, probably related to maldevelopment of the bony ocular orbits. Thus, these experimental observations suggest that the cranil, facial, and dental peculiarities as well as the aortic lesion of the supravalvular aortic stenosis syndrome may be related to a derangement in vitamin D metabolism during pregnancy. [ABSTRACT FROM AUTHOR]

Provides information on the proposed changes by the U.S. Food and Drug Administration concerning formula products and vitamin-mineral dietary supplements for infants. Protein concentration and quality; Recommendation on the intake of vitamin D; Requirement for ascorbic acid during infancy.

The article reports on the findings that calcium metabolism is disturbed by anticonvulsant drug therapy. It has been suggested that a drug-mediated enzyme induction may be the mechanism responsible by causing a greatly increased inactivation of vitamin D in these patients. In the previous study 71 percent of the 120 serum calcium determinations and nine percent of the 120 cerebrospinal fluid calcium determinations were subnormal. The anticonvulsant action of phenobarbitone and perhaps of other antiseizure drugs is linked with their interference with the cellular protein binding of calcium and other cations.

Determination of calcium absorption was studied in 25 consecutive and unselected patients aged 35-77 years, who had undergone gastric resection one to 24 years previously. There was evidence of bone disease in seven patients and in three of these the two-hour serum level45 of CA following oral administration of Ca45Cl2 was abnormally low. Following Vitamin D replacement, absorption returned to normal in one patient. In the other four patients with bone disease calcium absorption was normal, suggesting that calcium malabsorption is not the only etiologic factor in postgastrectomy bone disease. No relationship could be established between calcium malabsorption and the length of the postgastrectomy interval, type of surgical procedure or presence of steatorrhea. [ABSTRACT FROM AUTHOR]

A case of regional enteritis has been documented for a period of over 18 years, presenting the following progressive phases: Enteritis within the first and second years; the appearance of prestenosis or string sign in the fourth year; radiologically interpreted fistulous tracts in the sixth year; progressive obstruction by the 13th year, and unremittent obstruction by the 15th year; marked malnutrition existed as a constant factor for a period of 16 years. Surgical excision of what was considered all of the diseased tissue plus the right colon presented the challenge of a "short bowel syndrome" which in this case was characterized by: 1. A maximum absorptive surface limited to duodenum and two feet of jejunum. 2. Complete absence of ileum, ileocecal valve and right colon. 3. A resultant small bowel rapid transit time (six to seven bowel movements a day), an absence of B12 absorption, disturbance of enterohepatic bile circulation, potential water-electrolite disturbance. Aside from hypocholesteremia, the late effects of bile-dependent substances, Vitamin D, Vitamin K, carotene, have not yet presented a problem. In the two years of therapeutic management, the patient has gained 38 pounds and appears nutritionally balanced. He has freedom of movement which includes travel. Note contrasting pictures of patient immediately postoperative and two years postoperative. [ABSTRACT FROM AUTHOR]

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

1. The quantitative distribution of alkaline phosphatase and glucose-6-phosphate dehydrogenase in proliferating and hypertrophic zones of rachitic rat cartilage during healing induced by vitamin D administration or starvation is presented. 2. Alkaline phosphatase activity in the hypertrophic zone is about three times greater than that of the proliferating zone of the normal weanling rat and approximately four times greater in the rachitic rats. 3. Following a single dose of vitamin D (8000 I. U.) there was a significant elevation in alkaline phosphatase activity of the proliferating zone. A less significant increase was observed in the proliferating zone of rats which had breen fasted 48 hours. 4. There was a significant decrease in the alkaline phosphatase activity of the central region of hypertrophic zone of cartilage after vitamin D treatment. No such decrease was observed in the fasted rats. 5. In the normal weanling rat glucose-6-phosphate dehydrogenase (G-6-PDH) activity was greater in the proliferating zone as compared to the hypertrophic zone. In the untreated rachitic rat the enzyme content was about the same in the two zones. 6. Following vitamin D treatment there was an appreciable decrease in the G-6-PDH activity. No such decrease was observed in the fasted rat. [ABSTRACT FROM AUTHOR]

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Calcified Tissue Research is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Cites the case of a fifty-seven-year-old female with systemic sclerosis and vitamin D intoxication. Medical history; Clinical diagnosis; Therapeutics.

The article explores the mineral ash content of bones and teeth in rats recovering from phosphorus deficiency. Details are provided about the correlation of body weight gain and mineral ash content among phosphorus deficiency-recovering rats. The role of Vitamin D in helping rats recovery from phosphorus deficiency is also examined.

The article focuses on experiments concerning the periodic precipitation of calcium salts in organic substances. The conclusion is that lecithin, vitamin D, cholesterin, and aspartic acid are factors in the process of rhythmic strata formation and that the pH level of the medium affects the development of a periodic ring structure.

The article discusses a study that investigated the impact that vitamin D has on the health of teeth and jaws in both humans and rats. The impact that vitamin D had on the dentin apposition and tooth eruption of rats is mentioned. The author states that there were no big differences between the skeletal calcification of treated and untreated animals.

The article discusses a study on the effects of vitamin D on dentin in dogs. It was found that vitamin D applied to carious teeth in dogs has the same effects as vitamin D that is eaten. Secondary dentin formed in the pulp cavity is not influenced by vitamin D. Additionally, vitamin D caused systemic side effects such as hypercalcia and hypercalcemia.

Eighteen black and white weanling rats were divided equally into three groups, and each group received a diet which was either adequate in an respects, deficient in calcium only or in calcium and vitamin D. After 7 weeks each rat received an intra-peritoncal injection of 3H-protine (5μ Cl/g body weight; 578 m Ci/mM) and was sacrificed 5 hours later. The buccal mucosa and the attached gingiva were removed, the unbound labelled proline. removed by dialysis and salt soluble and insoluble tissue fractions were separated by dialysis and filtration. Each fraction was gelatinised then hydrolysed and hydroxyproline estimation and tritium counting were carried out on the hydrolysate. Larger amounts of insoluble than of salt soluble collagen were recovered. Labelled proline was incorporated in measurable amounts into the insoluble collagen in the relatively short interval before sacrifice. The specific activities of the salt soluble collagen were greater than those of the insoluble collagen and showed greater variation within each dietary group. The rate of incorporation of labelled proline into insoluble oral collagen in rats deficient in calcium was significantly (p> 0.01) greater than normal and was significantly decreased (p >.0.01) in rats deficient in calcium and vitamin D. [ABSTRACT FROM AUTHOR]

An histological investigation has been carried out on the periodontal tissues of young rats fed for eight weeks on diets deficient either in calcium (calcium content 0.026 per cent; calcium to phosphorus ratio 0.058), vitamin D, or calcium and vitamin D, in which protein was supplied either as blood albumen or egg albumen. When the diet contained blood albumen, the deficiency of calcium resulted in alveolar changes resembling osteoporosis and in a reduction in the number and diameter of the fibres of the periodontal ligament. When the diet contained blood albumen, the deficiency of calcium and vitamin D caused alveolar changes resembling osteoporosis and a reduction in the number and diameter of the fibres of the periodontal ligament. The deficiency of vitamin D had no obvious effect on the periodontal tissues of the rat. The substitution of egg albumen for the blood albumen in the diets intensified the osteoperotic changes caused by the deficiency of calcium. In rats deficient in calcium and vitamin D it superimposed an osteomalacic change, resulting in a condition of the alveolar process which resembled a combination of osteomalacia and osteoporosis. It also increased the incidence of areas of resorption of primary cementum in all dietary groups. The cementoid on the surface of secondary cementum behaved under these conditions of dietary stress in the same way as the osteoid. The manner in which the dietary deficiencies may produce these changes is discussed. [ABSTRACT FROM AUTHOR]

Toxic doses of vitamin D2 (5 × 100000 U) were administered to lathyritic rats which received amino-acetonitrile in drinking water for 15 days. The peridontal membrane (PD M) of the molars was examined both histologically and biochemically. The PDM collagen of' the lathyritic animals could be extracted with cold 0.15 M NaCI, whereas that of the normal controls, or of the animals which received either the vitamin alone or both the lathyrogen and the vitamin was not extractable. Ossification of the PDM and supraalveolar connective tissue was apparent in the lathyritic group which received toxic doses of the vitamin but not in either lathyrism or hypervitaminosis alone. It is concluded that whereas the release of calcium from bone or the increased absorption of the mineral from the intestine is affected by vitamin D, its deposition in the soft connective tissues may depend on the nature of the protein matrix. [ABSTRACT FROM AUTHOR]

The article presents a study examining the influence of vitamin D, fats, and fatty oils upon the susceptibility of laboratory rats to dental caries. The discovery in a previous study that the presence of corn oil or oily preparations of vitamin D reduced the occurrence of caries in rats fed a diet of coarsely ground rice is noted, mentioning that the study in the article seeks to determine whether the effect of the vitamin D preparations was due to the fact that they contained oil.

The article discusses a study on the influence of diet on the control of dental caries in children. Researchers experimented with various diets in children and watched for increases and reductions of dental caries. They were unable to discover any particular dietary factors that significantly influenced dental caries. However, the experiments showed that vitamin D is important for overall dental health.

The article discusses a study on the induction of dental caries in rats. Researchers experimented with the diets of rats and studied the teeth throughout the experiments. It was discovered that vitamin D deficiencies caused by a reduction in calcium and phosphorus in the diet caused lesions to appear on the teeth.

The article looks at a studies conducted to assess the dietary factors relevant to the development and maintenance of teeth. Studies which consider the relevance of vitamin C deficiencies to instances of pain within unerupted teeth are discussed. The author reviews the importance of vitamins A, B, C, and D in the maintenance of normal teeth structures.

The article focuses on the use of nutrition in preventative dentistry. It comments on the discovery of Vitamins A, B, C, and D and on the effect that Vitamin C deficiency has on the teeth and gums. It mentions that a diet consisting primarily of cereal grains will retard growth in young rats and be insufficient to maintain the health of adult rats. It comments on different groups of foods, including meat, milk, cereal grains, and green leafy vegetables.

Thyroid parafollicular cells of normocalcemic and vitamin D-treated rats were investigated by electron microscopy and with the histochemical fluorescence technique of Hillarp and Falck. Administration of high doses of vitamin D caused hypercalcemia and an extensive degranulation of the parafollicular cells. The formation and storage of monoamines in granulated and degranulated parafollicular cells was investigated by fluorescence microscopy after injection of monoamine precursors (DOPA, 5-HTP), alone or in combination with Ro 4-4602, nialamide or reserpine. No fluorescence was observed in parafollicular cells of untreated rats. l-DOPA and l-5-HTP (but not the corresponding D-amino acids) were taken up by a process closely linked to the decarboxylation of the amino acids to the corresponding amines (dopamine and 5-hydroxytryptamine). Treatment with vitamin D did not seem to affect the formation of amines in the parafollicular cells or the formation and storage of amines in other cell systems investigated. The amine itself (dopamine) was not taken up by the parafollicular cells. In normocalcemic rats, the amine formed was retained in the cytoplasm of the parafollicular cells by a partially reserpine-resistant mechanism. The storage of amines is concluded to occur in association with the calcitonin-containing granules. In parafollicular cells of vitamin D-treated rats, a certain amount of amine was bound in the cytoplasm in the absence of typical granules. As a considerable amount of calcitonin is known to remain in the thyroid of vitamin D-treated rats, the present observations may indicate an association between the amine and the polypeptide hormone calcitonin, whether the latter is confined to typical granules or not. [ABSTRACT FROM AUTHOR]