Detection of Lyman agr Emission from the Saturnian Disk and from the Ring System.

A rocket-borne spectrograph detected H I Lyman alpha emission from the disk of Saturn and from the vicinity of the planet. The signal is consistent with an emission brightness of 700 rayleighs for the disk and 200 rayleighs for the vicinity of Saturn. The emission from the vicinity of the planet may be due to a hydrogen atmosphere associated with the saturnian ring system.

Functions of vitamin E in reproduction and in prostacyclin and immunoglobulin synthesis in rats.

The bioactivities of RRR-alpha-, beta-, gamma-, and delta-tocopherol (T) and R-alpha-tocotrienol (R-alpha-TT) were determined in rat resorption-gestation tests. The ranking order was RRR-alpha-T greater than RRR-beta-T greater than RRR-gamma-T greater than or equal to R-alpha-TT greater than RRE-delta-T. Accordingly, the biopotency of a palm-oil residue was assessed and expressed as alpha-tocopherol equivalents (alpha-TEs). The release of pyruvate kinase, a variable in the nutrition-linked necrotizing myopathy, into the plasma was dose-dependently inhibited by the RRR-alpha-T standard and the corresponding alpha-TE from this residue. Prostacyclin synthesis from aorta segments induced by thrombin or ionomycin was higher than the spontaneous release. However, there was no difference between the depleted group and groups treated with RRR-alpha-T or alpha-TEs from the palm-oil residue. Quantities of IgG in plasma of vitamin E-depleted rats were the highest. Upon supplementation with RRR-alpha-T or alpha-TEs from the palm-oil residue, reduced IgG concentrations were observed, similar to those of animals on a commercial diet containing adequate amounts of vitamin E.

Vitamin A in parenteral nutrition: uptake and distribution of retinyl esters after intravenous application.

Short-term parenteral application of vitamin A was examined in rats. Retinyl margarinate, which is chemically similar to physiological retinyl esters, was used in vitamin A-depleted rats to study uptake, distribution, and storage of retinyl esters in tissues. Vitamin A-depleted and Vitamin A-sufficient rats were infused with a micellar suspension of retinyl margarinate for 7 h and then killed at different times. Retinyl margarinate was directly taken up by all tissues examined. It appears that infusion of retinyl esters in micellar form provides a direct way to supply vitamin A to peripheral, vitamin A-dependent tissues. Therefore, a short-term infusion of retinyl esters with an emulsifier may be an effective means of preventing development of vitamin A-deficiency during long-term application of TPN, particularly in cases of liver dysfunction.

Modulation of the glycoconjugate expression in the tracheo-bronchial epithelium during sustained hypovitaminosis A.

The aim of this study was to determine the influence of sustained marginal vitamin A deficiency on the morphology of glycoconjugate expression in the tracheobronchial epithelium of guinea pigs. The distribution of oligosaccharide chains was investigated by applying a panel of 24 lectins. Glycosaminoglycans were detected by histochemical techniques. Number as well as morphology of ciliated cells showed no significant alterations in hypovitaminosis A. In contrast, the quantity of goblet cells was constantly decreased. A considerable reduction of secretory granules was also observed in these cells. Cytomembranes of ciliated cells (especially in the area of ciliar extensions) showed constant alterations in the patterns of lectin binding in vitamin A-depleted guinea pigs. Our results demonstrate a significant augmentation of accessibility of fucosyl molecules in proximal domains of glycoconjugates of ciliary membranes, whereas the presence of mannose structures seemed unchanged. In distal bronchioli, terminal N-acetylgalactosamine molecules were expressed. During marginal vitamin A deficiency, ciliary cells were specially labelled by GSA I(B), indicating presentation of terminal galactose molecules in alpha-position. Additionally, the cytoplasm of epithelial cells demonstrated enhanced concentrations of polyantennary oligosaccharide core structures. Staining of epithelial cells by VVA was restricted to control specimens. Abundance of N-acetylglucosamine residues on the non-reducing terminus of oligosaccharides was significantly enhanced in the connective tissue of depleted animals as demonstrated by the binding patterns of GSA II. We suggest that altered oligosaccharide patterns may contribute to enhanced predisposition to tracheobronchial infection in marginal vitamin A deficiency.

Impaired responses to sweet taste in vitamin A-deficient rats.

In brief-exposure, two-choice preference tests (sucrose solution v water), vitamin A-deficient (VAD) rats exhibited a decreased preference for sucrose relative to control rats. There was no difference in total fluid intake from both choices between the two groups, nor was any significant difference found in circumvallate taste papilla keratin size. It is concluded that the impaired preference for sucrose in VAD rats is due to a specific impairment in taste sensation rather than general malaise.

Characterization of glycoconjugate expression during development of Meckel's cartilage in the rat.

The staining patterns of 24 biotinylated lectins were analyzed in serial sections of the mandible of 13- to 21-day-old rat embryos by means of the avidin-biotin-peroxidase method. A ubiquitous distribution of binding sites was demonstrated after incubation with Con A (Canavalia ensiformis), DSL (Datura stramonium; except bone matrix), and WGA (Triticum vulgare). ECL (Erythrina cristagalli), GSL I (Griffonia simplicifolia), SJA (Saphora japonica), VVL (Vicia villosa), DBA (Dolichus biflorus), UEA I (Ulex europeus), and LTA (Lotus tetragonobolus) were constantly negative. In early stages of development, GSL II (Griffonia simplicifolia II) was a selective marker of prechondral blastema. In contrast, PNA (Arachis hypogaea) did not stain condensing mesenchyme. During chondrogenesis of Meckels's cartilage a general decrease of lectin binding was observed. Mature cartilage matrix was constantly negative. Chondrocytes were marked by the lectins PSA (Pisum sativum), WGA, PHA-E, and PHA-L (Phaseolus vulgaris E and L). A strong GSL II binding was restricted to the mesial-superior region of the perichondrium. In later stages, several lectins revealed significant differences between preskeletal ("central") areas and the remaining ("peripheral") mesenchyme. A clear binding reaction was noted in central regions by applying LEA (Lycopersicon esculentum) and STL (Solanum tuberosum), while the peripheral tissue was only faintly stained. Developing bone was specifically marked by succinylated WGA (sWGA). The lectins LCA (Lens culinaris) and RCA (Ricinus communis) bound to fibers and extracellular matrix of the connective tissue. Jacalin (Artocarpus integrifolia) and SBA (Glycine max) binding sites were found in macrophages. Affinity of VAA (Viscum album) increased parallel with maturation of endothelial cells. Specific lectin-binding patterns revealed no correlation with the distribution of glycosaminoglycans. The results demonstrate a general reduction of oligosaccharide structures during development of Meckel's cartilage. From our observations we conclude that intralaminar glucose and/or mannose sequences as well as terminal sialic acid molecules are ubiquitously distributed, while terminal alpha-fucose was constantly negative. Lectin-binding patterns of macrophages may reflect the presence of specifically linked terminal galactose. Our findings indicate that oligosaccharides terminating in N-acetylglucosamine are bone-specific. The significance of the restricted staining of the perichondrium by GSL II remains to be elucidated.

Vascular injuries within the hepatoduodenal ligament: recognition by laparoscopic color Doppler ultrasound.

BACKGROUND: Lesions of vascular structures are rare but serious complications of laparoscopic cholecystectomy. The purpose of this blind randomized animal study was to investigate the possibility of detecting different vascular lesions within the hepatoduodenal ligament using laparoscopic color Doppler ultrasound (LCDU). METHODS: Twenty-four lesions of the hepatic artery and portal vein were created laparoscopically in six farmer pigs using titanium clips. The following injuries were studied: (a) partial occlusion of the hepatic artery (eight cases), (b) complete occlusion of the hepatic artery (eight cases), (c) partial occlusion of the portal vein (eight cases). There were also eight cases without lesions of the vascular vessels. The order in which the injuries were created was randomly assigned. The study was performed in a blind fashion. Recognition of the injuries was attempted with LCDU. RESULTS: All injuries were recognized correctly by LCDU. There were no false positive results. The clips were reliably located. Using color Doppler imaging, partial occlusions of the hepatic artery and portal vein were visualized by changes of the blood flow from laminar to turbulent behind the clip. Complete occlusion of the hepatic artery was recognized as a complete cessation of the colored blood flow. CONCLUSION: LCDU is a very efficient tool for visualizing vascular structures and evaluating the bloodstream. Partial or complete vascular occlusion by clips that may occur as a result of difficult dissection during laparoscopic cholecystectomy can be visualized reliably using this technique.

Influence of vitamin A deficiency on the excretion of uromucoid and other substances in the urine of rats.

Male Fü-albino rats were weaned at the age of four weeks and maintained on a vitamin A-deficient diet. When they were 14-18 and 21-26 weeks old, the concentration of uromucoid, calcium and other substances possibly important for the pathogenesis of urinary calculi were determined. Reduced uromucoid excretion with hypercalciuria and reduced phosphate levels were observed. Subsequent examination of the kidneys did not demonstrate the presence of nephrocalcinosis or lithiasis. The relation between vitamin A, the synthesis of uromucoid and AMPS and calcium metabolism in the renal tubules is discussed.

Asymptomatic carotid arterial disease in patients presenting with angiographically proven coronary artery disease.

Atherosclerosis is a systemic and progressive disease process. However, the patterns of disease and the sequence of arterial involvement need further definition. A select group of patients initially presenting with coronary arterial disease was evaluated for evidence of hemodynamically significant carotid arterial disease. Eight per cent of patients were found to have hemodynamically significant carotid arterial disease by the oculopneumoplethysmography (Gee OPG). This low incidence of carotid arterial disease is in contrast to patients who present with carotid arterial disease who are found to have a high incidence of coronary artery disease. This would suggest that either the coronary artery disease develops first or that there is a specific pattern of atherosclerotic vascular disease where patients have coronary artery disease without hemodynamically significant carotid disease. Long-term follow-up on patients initially presenting with coronary arterial disease will help further define this question.

Cerebral monoamine metabolism in guinea-pigs with ascorbic acid deficiency.

Guinea-pigs kept on a diet deficient in vitamin C showed, after 3 weeks, a marked decrease of ascorbic acid in brain and blood leucocytes as well as of the activity of alkaline phosphatase in blood plasma. Pair-fed animals did not exhibit these changes. The alpha-methyl-p-tyrosine (alpha MpT)-induced diminution of noradrenaline in the hypothalamus and the rest of the brain was attenuated in pair-fed animals, but restored in guinea-pigs deficient in ascorbic acid. The cerebral noradrenaline content (without administration of alpha MpT) showed a decrease in both pair-fed and ascorbic acid deficient animals. The noradrenaline of the heart exhibited a similar tendency. The alpha MpT-induced dopamine decrease in the striatum of ascorbic acid deficient animals was attenuated and the dopamine content (without alpha MpT administration) decreased. Pair-fed animals showed a similar tendency. The striatal concentration of homovanillic acid (HVA) was diminished in both pair-fed and ascorbic acid deficient guinea-pigs. The cerebral content of 5-hydroxyindoleacetic acid showed a decrease in pair-fed as well as in ascorbic acid deficient animals. It is concluded that ascorbic acid deficiency enhances the turnover of brain noradrenaline, whereas under-nutrition without ascorbic acid deficiency (pair-feeding) diminishes the turnover of cerebral noradrenaline, 5-hydroxytryptamine and striatal dopamine.

Topical application of vitamin A reverses metaplasia of rat vaginal epithelium: a rapid and efficient approach to improve mucosal barrier function.

Retinyl palmitate and its metabolites retinol and retinoic acid control growth and epithelial differentiation. Systemic or local vitamin A deficiency induced by malnutrition, continuous chemical irritation or locally induced by inflammation causes squamous metaplastic changes in the epithelium of mucous membranes. We demonstrate that in an animal model topically applied retinyl palmitate can be taken up by the mucosal cells independently from the systemic supply. Under in vivo conditions metabolic changes in vaginal epithelium of rats were shown to be reversed by treatment with topical retinyl palmitate. - After only two days treatment squamous metaplastic vaginal epithelium in rats shows a reversal of the epithelium into a normal phenotype which continues after cessation of the treatment for 7 to 11 days. Higher concentrations and longer retention times lead to a statistically significant (p = 0.025) increase in the protection time. These data demonstrate that squamous changes induced by vitamin A deficiency can be totally reversed with topically applied retinyl palmitate.

Inappropriate secretion of antidiuretic hormone as a postoperative complication in a child with a medulloblastoma.

We report the case of a child with a medulloblastoma who developed inappropriate secretion of antidiuretic hormone postoperatively. The etiology of this condition and the related literature are discussed.

A cerebrospinal fluid glucose biosensor for diabetes mellitus.

A cerebrospinal fluid (CSF) glucose biosensor is introduced. The biosensor is a polarimeter that measures the rotation of plane polarized light proportional to glucose concentration. Preliminary in vitro studies revealed a linear response with good sensitivity over a range of glucose solutions (0-400 mg/dl). Anesthetized, adult dogs underwent intravenous glucose loading, and these preliminary in vivo studies resulted in good correlation (r = 0.98) between CSF polarimeter readings and CSF glucose by laboratory assay. This in vivo correlation suggests that both mutarotation of glucose anomer and changes from other optically active substances present in CSF are either negligible or constant over the range of glucose concentrations studied. The CSF polarimeter showed a significant rise soon after the intravenous loading of glucose (1-30 min) but a longer lag time (45-60 min) between the peak blood glucose and peak CSF polarimeter reading. This preliminary work extends, to the CSF, the concept of measuring optical rotation.

Expression patterns of complex glycoconjugates and endogenous lectins during fetal development of the viscerocranium.

Experimental evidence suggests that carbohydrates and their corresponding receptors (endogenous lectins) decode biological information. Therefore, the expression of complex oligosaccharides--the potential ligand part of this recognition system--during chondrogenesis and osteogenesis was determined in the viscerocranium of fetal rats by mapping the staining patterns of exogenous lectins. Results were compared with the expression of bone- and/or cartilage-specific core proteins and the binding profiles of neoglycoconjugates. These synthetic tools make possible the localization of sugar-ligand-binding sites. The spatial and temporal distribution patterns of glycoconjugates were highly dynamic and demonstrated a clear correlation with characteristic morphological modifications. The glycobiological characterization of precartilage mesenchymal cells revealed distinct differences compared to prospective bone anlagen. Especially the binding of the exogenous lectin from Griffonia simplicifolia II, that selectively visualized prechondral aggregations, reveals that regulation of early chondral growth is at least phenomenologically correlated with a relatively atypical oligosaccharide composition terminating with N-acetylglucosamine.

Bioactivity of cis and dicis isomers of vitamin A esters.

In order to declare the accurate vitamin A effectiveness of foodstuffs and synthetic vitamin A preparations, the biological activity of the individual isomers has to be known. Total activity is expressed as all-trans vitamin A equivalents which are calculated by multiplication of analytical content of each isomer with the corresponding biopotency factor. The biological activity of four cis and three or four dicis isomers of vitamin A acetate and palmitate was determined by means of rat vaginal smear assays. The purity of the compounds, the content and isomerisation in stock solutions were checked by HPLC methods prior to their dilution and application to the experimental animals. Based on analytical contents the following activities were found for vitamin A acetate isomers: all-trans 1.00, 13-cis 0.76, 11-cis 0.31, 9-cis 0.19, 7-cis 0.18, 9,13-dicis 0.16, 11,13-dicis 0.18, 9,11-dicis approx. 0.03. The corresponding values for vitamin A palmitate were: all-trans 1.00, 13-cis 0.73, 11-cis 0.34, 9-cis 0.19, 7-cis 0.14, 9,13-dicis 0.21, 11,13-dicis 0.20, 9,11-dicis approx. 0.04, 7,11-dicis approx. 0.12. The vitamin A activity of the cis isomers ranged from about 0.75 for 13-cis to about 0.05 for 9,11-dicis. For the cis series, a biopotency relationship depending on the distance between the beta-ionone ring system and the cis configuration could be observed.

Stereoisomers of alpha-tocopheryl acetate--characterization of the samples by physico-chemical methods and determination of biological activities in the rat resorption-gestation test.

Stereoisomers of alpha-tocopheryl acetate (alpha-TA) have been identified and characterized by means of a recently developed gas-liquid chromatographic technique prior to the determination of their biopotency. It has been shown that totally synthetic all-rac-alpha-TA (dl-alpha-TA) is composed of four pairs of diastereomers (RRS-SSR, RRR-SSS, RSR-SRS, RSS-SRR) in virtually equal proportions. In addition, it has been verified that 2-ambo-alpha-TA (partially synthetic, ex phytol) is an equimolar mixture of RRR-alpha-TA and 2 epi-alpha-TA. Finally, it has been demonstrated that the RRR-alpha-TA (d-alpha-TA) tested was diastereomerically pure. The biopotencies of these alpha-tocopheryl acetate stereoisomers have been evaluated by standardized rat resorption-gestation test. Our first study concerned the comparison of all-rac-alpha-TA with RRR-alpha-TA and resulted in a potency ratio of 1:1.50 or 1:1.48. The first value was derived from the amounts weighed out while the second value was based on the analytically determined alpha-TA content of the stock solutions. Similarly, the comparison of 2-ambo-alpha-TA with RRR-alpha-TA yielded potency ratios of 1:1.32 (amount weighed out) and 1:11.36 (alpha-TA analysed). The influence of the configuration of the side-chain on biopotency has been analysed by a second series of investigations. Comparison of all-rac-alpha-TA with 2-ambo-alpha-TA resulted in a biopotency ratio of 1:1.09 (amount weight out) and 1:1.10 (alpha-TA analysed). However, these slightly higher values for 2-ambo-alpha-TA did not reach statistical significance. These studies demonstrate the validity of the established potency ratio of 1:1.36 for 2-ambo-alpha-TA to RRR-alpha-TA by direct comparison of these compounds. In addition, the experimental ratios for all-rac-alpha-TA to 2-ambo-alpha-TA and for all-rac-alpha-TA to RRR-alph-TA can be grouped into the expression (1:1.10)/(1:1.48) = 1.35. This indirect comparison further supports the accepted value of 1.36 USP Units for 1 mg d-alpha-tocopheryl acetate.

Interaction of erythorbic acid with ascorbic acid catabolism.

After a vitamin C depletion period of 12 days supplementing erythorbic acid (50 mg/day/kg bodyweight) over 16 days significantly accelerated the catabolism of a newly ingested tracer dose of (1-14C) ascorbic aicd in guinea pigs in comparison to animals supplemented with ascorbic acid (5 mg/day/kg bodyweight), but this effect of erythorbic acid could not be normalized by additional supplementation with ascorbic acid. Half-lives for (1-14C) ascorbic acid (50% of the dose excreted) were drastically reduced from 97 h to 50 h and 59 h, respectively. Also figures on the retention of radioactivity showed the availability of ascorbic acid to be reduced. This is in accordance with the significant reduction in size of ascorbic acid bodypool, and in weight gain in the groups receiving erythorbic acid, or erythorbic and ascorbic acids. The bioavailability was calculated to be strongly depressed to nearly 50% of the total ingested biologically active material (ascorbic plus erythorbic acids), assuming erythorbic acid to have only one-twentieth of the biological activity of ascorbic acid.

Stereoisomers of alpha-tocopheryl acetate. IV. USP units and alpha-tocopherol equivalents of all-rac-, 2-ambo- and RRR-alpha-tocopherol evaluated by simultaneous determination of resorption-gestation, myopathy and liver storage capacity in rats.

Whereas the alpha-tocopheryl acetate (alpha-TA) stereoisomers have frequently been compared in various vitamin E tests, only little studies have been made on the free alpha-tocopherols. For this reason, comparative tests of the alpha-tocopherol (alpha-TOH) stereoisomers were made by means of the resorption-gestation method, not only individually but also against the USP standard all-rac-alpha-TA. In some of these tests, the parameter resorption-gestation was supplemented by determination of pyruvate kinase (PK) activity as well as by measurement of the vitamin E level in the liver. Quantitative statistical evaluation of the results was made by weighted probit analysis or by symmetrical parallel line assays. Comparison of all-rac-alpha-TOH (dl-alpha-TOH) with RRR-alpha-TOH (d-alpha-TOH) in the resorption-gestation test revealed an activity ratio of 1:1.38. Compared with 2-ambo-alpha-TOH, RRR-alpha-TOH was more active by a factor of 1.34 (resorption-gestation) or 1.45 (myopathy). On account of its great importance in practice, the comparison between RRR-alpha-TOH and the USP standard was repeated three times. With the parameters resorption-gestation and myopathy, mean activities on a weight basis of 0.69 and 0.74, respectively, were measured. These results fail to confirm the established activity of 1 mg RRR-alpha-TOH = 1.49 USP units. If vitamin E activity is to be given in alpha-tocopherol equivalents (alpha-TE), the values are referred to RRR-alpha-TOH and the calculation is made with their reciprocals. Depending on the parameter used, the activity of 1 mg all-rac-alpha-TA was equivalent to 1.45 alpha-TE (resorption-gestation) or 1.35 alpha-TE (myopathy) and was thus noticeably higher than the established value of 0.67 alpha-TE. For the first time, three parameters were determined simultaneously in the comparison of all-rac-alpha-TOH with the USP standard. Quantitative evaluation yielded the following activities: Resorption-gestation, 0.52; Myopathy, 0.63; liver storage, 0.68. The currently accepted value of 1.10 USP units for 1 mg all-rac-alpha-TOH was thus not even reached approximately. In the light of our experimental findings as well as of those of other laboratories, the activities of the alpha-tocopherol stereoisomers expressed in USP units and of their esters expressed in alpha-tocopherol equivalents need to be corrected.

Biopotency of vitamin K. I. Antihemorrhagic properties of structural analogs of phylloquinone as determined by curative prothrombin time tests.

Relative antihemorrhagic properties of structural analogs of transphylloquinone (vitamin K1) have been determined by curative prothrombin time tests with vitamin K-deficient chicks. Analogs (where applicable) and the phylloquinone standard had (all-) rac-trans configuration, and all compounds were well characterized (structure, purity, trans: cis). Compounds were administered as single oral doses according to the up-and-down procedure. Estimation of mean effective doses allowed a reliable calculation of relative activities for analogs in comparison with vitamin K1 standard. 2', 3'-Dihydro-phylloquinone had a relative activity of only 6.7%, i.e. it was about 15 times less active than phylloquinone. Further reduction of this analog led to 2',3',5,6,7,8-hexahydro-phylloquinone which was completely inactive. Analogs with oxygen functions in the side chain, 6'-hydroxy-K1, 6'-oxo-K1, and 7'-hydroxy-6'-oxo-K1, displayed relative activities of 20.5%, 31.9%, and 30.5%, respectively. Phylloquinone-2,3-epoxide was 1.7 times more active than the phylloquinone standard. An analog with a 7-carbon side chain ending with a carboxy group (in mammals a urinary metabolite of vitamin K1) and its corresponding ethyl ester derivative were practically inactive.

Stabilization of rat heart mitochondria by alpha-tocopherol in rats.

alpha-Tocopherol (alpha-T) acts by different mechanisms: scavenging free oxygen radicals (FOR) and stabilizing membranes; both may contribute to the prevention of the pathogenesis of diseases like cardiovascular events. The present work shows that alpha-T breaks the vicious cycle generated by damaged mitochondria. The latter stimulate the immune system increasing FOR formation that leads to more damaged mitochondria. alpha-T inhibits lipid peroxidation induced by recombinant human tumor necrosis factor (rh-TNF). Polymorphonuclear neutrophils (PMN) are activated by TNF to produce FOR causing lipid peroxidation of cardiomyocyte membranes. Since TNF is used as a therapeutic agent against certain tumors, treating patients with alpha-T could protect them against systemic side effects of TNF.