[Factors influencing the vitamin A concentration in the liver of cattle]. / Einflussfaktoren auf die Leber-Vitamin-A-Konzentration bei Rindern.

Nineteen long-term individual- and group-feeding experiments with 180 male calves, 338 growing bulls, 302 heifers, and 344 dairy cows were carried out in order to measure the influence of feeding (straw, silages or green fodder as roughages) and different vitamin-A supplies (0-40,000 IU per 100 kg body weight per day in growing cattle or 0-120,000 IU per dairy cow per day) on liver vitamin-A concentration. All together, 2,127 biopsies from livers were taken for retinol analysis. At the end of six growth experiments animals were slaughtered. Liver vitamin-A concentration of calves depends on their term at birth and is associated with the carotene intake of their mothers. The carotene content of feeds and the vitamin-A supply are the most important influencing factors on liver vitamin-A concentration of growing and lactating cattle. On the average, livers of calves fed with colostrum contained 100-200 IU, those of growing cattle fed with grass and legumes or with silages contained 200-300 or 100-200 IU resp., and those of cows fed with green fodder or silage contained 300-600 or 100-300 IU vitamin A resp. per g fresh liver. There were also values outside of the variations mentioned above. The vitamin-A storage capacity of liver and the effects of oral and parenteral vitamin-A supply to depleted calves and growing cattle were also tested.

[The influence of oral niacin doses during different dietary protein levels on indexes of rumen fermentation, blood parameters and fattening performance of young bulls]. / Untersuchungen zum Einfluss oraler Niacingaben bei unterschiedlicher Proteinversorgung auf Kennzahlen der Pansenfermentation, Blutinhaltsstoffe und die Mastleistung von Jungbullen.

The influence of added niacin (0, 0.5 or 1 g per animal per day) and different crude protein contents (9.2 to 12.0% of DM) or the supply of various N-sources (urea, rape seed meal, soya bean meal, fish meal) were investigated on rumen fermentation, blood parameters, feed intake, weight gain and dry matter (DM) intake per weight gain in three individual feeding experiments with 156 growing bulls weighing between 175 and 300 kg per animal. Niacin supplementation did not significantly influence (P > 0.05) investigated parameters of rumen fermentation and blood. Ruminal propionate concentration increased insignificantly (from 18.9 to 19.5 moles per 100 moles on the average), inorganic P of blood serum somewhat decreased (from 2.98 to 2.82 mmol per 1) when niacin was added (P > 0.05). Protein level did not significantly influence rumen fermentation and blood parameters except an increased urea concentration in the blood of cattle fed with diets richer in protein. The DM intake of control bulls and niacin supplemented animals amounted to 6.35 and 6.46 kg per animal per day on average. Influence of niacin on DM intake varied in dependence on protein source. The daily weight gain increased from 1003 (control) to 1040 g per animal per day (+ niacin, P > 0.05). Niacin increased weight gain of bulls of urea (+ 43 g) and rape seed or soya bean meal added rations (+ 60 g per animal per day), but did not influence the weight gain in fish meal added rations. Increased weight gain resulted from ruminal and metabolic effects (about 2/3) as well as enhanced feed intake of bulls (about 1/3). Feed efficiency mostly improved.

U1 SnRNP association with HnRNP involves an initial non-specific splice-site independent interaction of U1 SnRNP protein with HnRNA.

Precursor mRNA is complexed with proteins in the cell nucleus to form heterogeneous nuclear ribonucleoprotein (hnRNP), and these hnRNPs are found associated in vivo with small nuclear RNPs (snRNPs) for the processing of pre-mRNA. In order to better characterize the ATP-independent initial association of U1 snRNP with hnRNP, an important early event in assembly of the spliceosome complex, we have determined some of the components essential to an in vitro reassociation of U1 snRNP with hnRNP. U1 snRNP reassociated in vitro with 40S hnRNP particles from HeLa cells and, similar to the in vivo hnRNP/U1 snRNP association, the in vitro interaction was sensitive to high salt concentrations. U1 snRNP also associated with in vitro reconstituted hnRNP in which bacteriophage MS2 RNA, which lacks introns, was used as the RNA component. Purified snRNA alone would not associate with the MS2 RNA-reconstituted hnRNP, however, intact U1 snRNP did interact with protein-free MS2 RNA. This indicates that the U1 snRNP proteins are required for the hnRNP/U1 snRNP association, but hnRNP proteins are not. Thus, the initial, ATP-independent association of U1 snRNP with hnRNP seems to be mediated by U1 snRNP protein(s) associating with hnRNA without requiring a splice-site sequence. This complex may then be further stabilized by intron-specific interactions and hnRNP proteins, as well as by other snRNPs.

[The vitamin A requirement and the vitamin A status of growing cattle. 2. Studies of fattening cattle]. / Untersuchungen zum Vitamin-A-Bedarf und zum Vitamin-A-Status wachsender Rinder. 2. Mitteilung. Untersuchungen an Mastrindern.

Three long time individual feeding experiments (greater than 258 days) with 48 beef cattle each (dairy breed and beef breed, 50% each) were carried out in order to measure the influence of various vitamin A supply (0, 2,500, 5,000 and 10,000 IU vitamin A per 100 kg body weight and day) on fattening and slaughtering performance, vitamin A concentration of liver and serum as well as carotene concentration of serum. The bulls consumed corn silage (experiments 1 and 2; 9.4 and 18.3 mg carotene per kg dry matter) or NaOH-treated and pelleted straw (experiment 3; no carotene). The roughages were supplemented with 2 (exp. 1 and 2) and 3 kg (exp. 3) concentrate per day. The vitamin A supply of corn silage diet did not significantly influence the dry matter intake (exp. 1: means: 6.95; 6.91 to 7.05; exp. 2: means: 6.54; 6.53 to 6.54 kg dry matter per animal and day) and the daily weight gain of bulls (exp. 1: means: 1076; 1028 to 1157; exp. 2: means: 1058; 1041 to 1057 g per animal). The bulls consumed 8.87 kg dry matter per day, the daily weight gain amounted to 1030 g per animal and day in experiment 3. The bulls of unsupplemented group reduced feed intake and weight gain after 150 days, an additional vitamin A supply was necessary. At the end of experiments 1 and 2 the liver vitamin A concentration of unsupplemented groups amounted to 38.8 and 65.9 mumol/kg, it increased after vitamin A supply (up to 153.4 mumol/kg). Feeding of pelleted straw effected a liver vitamin A concentration lower than 10 mumol/kg except the group supplemented with 10,000 IU vitamin A per 100 kg body weight and day (35.7 mumol per kg fresh matter of liver). The vitamin A concentration of blood is unsuitable for evaluation of vitamin A status of cattle. The carotene content of feeds and level of vitamin A supply determined the carotene concentration of blood. Recommendations for a suitable vitamin A supply of ration of growing cattle were given depending on body weight and type of diet.

[The vitamin A requirement and the vitamin A status of growing cattle. 1. Studies of calves]. / Untersuchungen zum Vitamin-A-Bedarf und zum Vitamin-A-Status wachsender Rinder. 1. Mitteilung. Untersuchungen an Kälbern.

Five experiments with 18 to 36 male calves each of the black and white dairy cattle breed (age: 14-21 days, initial live weight: approximately 45 kg per animal) were carried out in order to investigate the influence of various vitamin A supply (0-80,000 IU per 100 kg LW and day) on dry matter intake and weight gain as well as the vitamin A status of liver and blood plasma over 84 days. The calves consumed a diet free of carotene and vitamin A consisting of milk replacer, concentrate and chopped wheat straw. The calves were fed in three experiments for a longer time in order to observe the further vitamin A depletion. Nine animals consumed an unsupplemented ration, nine other one got 10,000 IU vitamin A per 100 kg LW and day. Biopsies of liver and plasma samples were taken from 4 animals per group every four weeks. The various vitamin A supplementation did not significantly influence the dry matter intake (Mean: 1.67; 1.48 to 1.80 kg DM per animal and day) and the weight gain of calves (Mean: 702, 599 to 770 g per animal and day). First vitamin A deficiency symptoms (reduced feed intake, decreased weight gain, diarrhoea etc.) were observed in animals of unsupplemented group after 100 days of experiments. After 84 days the vitamin A concentration of liver of animals of unsupplemented groups decreased to 1.3-32.2% compared with the begin of experiments (60.6-155.7 mumol/kg fresh matter). Up to 51% of initial concentration were found when 10,000 IU vitamin A per 100 kg LW and day were fed. About 25,000 IU vitamin A per 100 kg LW and day were required in order to keep the initial level of vitamin A concentration of liver. The plasma vitamin A concentration is unsuitable for estimation of vitamin A status of calves. The concentration of vitamin A of liver and plasma amounted to 114 mumol per kg and 0.25 mumol per litre at the begin of experiments. The vitamin A concentration of liver of unsupplemented group decreased to 20 mumol per kg, that of plasma increased to 0.28 mumol per 1 at the end. A strong vitamin A deficiency (liver concentration: less than 10 mumol/kg) may cause a decrease of vitamin A concentration of blood.

The core proteins of 35S hnRNP complexes. Characterization of nine different species.

Ribonucleoprotein complexes (hnRNP) containing fragments of heterogeneous nuclear (hn)RNA and sedimenting at 35-40 S were isolated from the nuclei of HeLa S3 cells using the pH 8.0/diffusion technique. These hnRNP complexes are thought to be part of the hnRNA processing apparatus. The major protein components (core proteins) were identified by their constant ratios in native particles and in 35S hnRNP particles reconstituted in vitro. All of the core proteins, with one exception, show an increase in Mr on sodium dodecylsulfate (NaDodSO4)/polyacrylamide gels containing 8 M urea, indicative of secondary structure elements resistant to denaturation by NaDodSO4. The nine core proteins found by us are: A1 [Mr(NaDodSO4) 31 X 10(3)/Mr (urea) 38 X 10(3), apparent isoelectric point, pIapp 9.3], A2 (32.5 X 10(3)/39 X 10(3), 8.4), B1a (35.5 X 10(3)/41 X 10(3), 8.8), B1b (35.5 X 10(3)/44 X 10(3), 8.3), B1c (35.5 X 10(3)/43 X 10(3), 5.7) B2 (37 X 10(3)/42 X 10(3), 9.15), C1 (39 X 10(3)/46 X 10(3), 9.2), C2 (40.5 X 10(3)/45 X 10(3), 5.55) and C3 (38.5 X 10(3)/37 X 10(3), 4.8). Individual proteins were electroeluted from two-dimensional gels and their amino acid composition determined. Difference indices were calculated and show a group of closely related basic proteins (A1, A2, B1a, B1b, B2, C1), two related slightly acidic proteins (B1c, C2) and a distinct acidic member (C3). Two-dimensional analysis of tryptic fragments and one-dimensional separation of peptides after V8 protease treatment support these data. Peptide mapping of the proteins A1 and A2 from bovine and human cells yields identical fragments indicating a high degree of cross-species conservation. An additional protein (D4: 44 X 10(3)/55 X 10(3), greater than 9.5) was found, which preferentially associates with heavier, oligomeric hnRNP structures. Only traces of actin are present in the 35S hnRNP fraction. All core proteins are modified by charge. A large part of the charge isomers arises by phosphorylation, which has been shown by labeling with 32PO4 in vivo and with [gamma-32P]ATP in vitro. In vitro the phosphate transfer is mediated by an endogenous protein kinase associated with the 35S hnRNP complexes. The major core protein A1 exists in two conformeric forms (A1 and A1x) of which only A1x serves as phosphate acceptor in vivo.

In vitro reconstitution of 35S ribonucleoprotein complexes.

Ribonucleoprotein complexes (hnRNP) sedimenting at 30-40 S and containing fragments of heterogeneous nuclear RNA (hnRNA) have been extracted from HeLa cell nuclei. Besides hnRNA fragments (8-12 S), the complexes contain eight mostly basic core proteins of Mr 31 000-41 000 as shown by two-dimensional gel electrophoresis. Other proteins (mostly of higher molecular weight) seem to be peripherally associated since they are lost after pelleting and recentrifugation of the hnRNP complexes. The particle dissociates into its protein components after digestion of the endogenous hnRNA fragments by micrococcal nuclease. After inactivation of the nuclease and addition of a wide variety of exogenous RNAs [MS2 phage RNA, poly(U), poly(C), poly(A), and poly(A,U)], a RNP particle is re-formed which resembles the native hnRNP complex according to its sedimentation value (35 S), its appearance in the electron microscope, its density in metrizamide, and its protein composition. No particles are formed on double-stranded RNA [poly(A) . poly(U)] or native DNA whereas denatured DNA allows complex formation. On MS2 RNA (3569 nucleotides), the formation of tri- and tetrameric complexes is observed. This indicates the presence of 900-1200 nucleotides per particle. In vivo, 40S hnRNP particles are a unit component of larger RNP structures. Hence, we conclude from our results that the hnRNP core proteins have the intrinsic capability to associate with nascent single-stranded hnRNA regions to form these RNP complexes. Because of the lack of any sequence specificity, the complexes may function in packaging of the hnRNA and in connection with other nuclear components may provide a scaffold for subsequent processing reactions.

m-Aminophenylboronate agarose specifically binds capped snRNA and mRNA.

m-Aminophenylboronate-substituted agarose binds specifically RNA chains carrying a mature 5' cap. The binding occurs most effectively at pH greater than 8 and involves diester formation between the negatively charged tetrahedric boronate group and the cisdiol of the ribose of the cap. The positive charge introduced by the m7G methylation is necessary for efficient binding although two closely spaced cis-diol groups alone (as in the cap analog NADH) are sufficient for binding. Non-capped RNA (like poly (U) and rRNA) or decapped RNA are not bound. It is shown that the matrix can be used for the isolation of capped small nuclear RNA and mRNA.

Malignant (androblastoma) Sertoli cell tumor of testes.

A case of malignant testicular tumor which originated in the Sertoli cells is reported. Metastases were studied by aortography and computerized axial tomography. The tumor presented no clinical evidence of hormonal activity and a long recurrence-free survival.