Showing papers by "University of Zurich published in 1970"
TL;DR: The RNA replicating enzyme induced by RNA phage Qβ consists of a single phage specific and three host specific polypeptide chains, and none are known subunits of E. coli DNA-dependent RNA polymerase.
Abstract: The RNA replicating enzyme induced by RNA phage Qβ consists of a single phage specific and three host specific polypeptide chains. At least one of the host subunits is shown to be essential for enzymatic activity, and none are known subunits of E. coli DNA-dependent RNA polymerase.
188 citations
TL;DR: Qβ replicase comprises four different polypeptides, only one of which is coded for by the phage genome.
Abstract: Qβ replicase comprises four different polypeptides, only one of which is coded for by the phage genome.
163 citations
TL;DR: A transcription factor, Ψr, which preferentially stimulates the synthesis of ribosomal RNA in vitro has been identified in crude extracts of E. coli and is also a component of Qβ replicase.
Abstract: A transcription factor, Ψ r , which preferentially stimulates the synthesis of ribosomal RNA in vitro has been identified in crude extracts of E. coli. This factor activity is also a component of Qβ replicase.
140 citations
TL;DR: The normalization of growth hormone release after one injection of testosterone might be helpful to exclude isolated growth hormone deficiency in boys with delayed puberty and small stature who present a doubtful growth hormone response to hypoglycemia.
Abstract: The effect of testosterone on plasma growth hormone response to hypoglycemia was studied in 4 patients with anorchia, in a patient with delayed puberty, and in a patient with panhypopituitarism. Insulin tolerance tests were performed a) without testosterone therapy, b) 2 days after a single injection of testosterone, and c) in 3 patients after 2–3 months of full replacement therapy. Testosterone led to an increased release of growth hormone in all 4 patients with anorchia and in the boy with delayed puberty. This increase appeared 2 days after a single injection of testosterone; it became still higher after 2–3 months of full replacement therapy. In the patient with panhypopituitarism, no growth hormone response was observed. The normalization of growth hormone release after one injection of testosterone might be helpful to exclude isolated growth hormone deficiency in boys with delayed puberty and small stature who present a doubtful growth hormone response to hypoglycemia.
119 citations
TL;DR: The effect of a long-acting testosterone preparation on growth, on skeletal maturation and on secondary sex characteristics was studied in 24 boys with sexual immaturity of different causes, finding that in patients with growth hormone deficiency the response is less marked.
Abstract: The effect of a long-acting testosterone preparation1 on growth, on skeletal maturation and on secondary sex characteristics was studied in 24 boys with sexual immaturity of different causes. In patients without growth hormone deficiency dosages above 100 mg/m2/month lead to a maximum growth velocity during the first 6 months of treatment (catch-up growth). Smaller initial dosages followed by a gradual increase to 100–150 mg/m2/month, lead to an imitation of the normal pubertal growth spurt. The time from the start of treatment to the development of axillary hair is inversely proportional to the mean dosage. In patients with growth hormone (GH) deficiency the response is less marked with respect to growth and to the development of secondary sex characteristics. To exert its full growth-promoting anabolic effect, testosterone apparently needs the presence of GH. To exert its full androgenic effect on the secondary sex characteristics, pituitary hormones are also necessary, but it is not clear whet...
114 citations
TL;DR: Pathways of axons from antennal receptor organs into the brain have been traced by means of anterograde experimental degeneration in Calliphora vicina and Periplaneta americana and degenerating nervous processes were found in the glomeruli of the ipsilateral deutocerebrum.
Abstract: Bei Calliphora vicina und Periplaneta americana wurde mit Hilfe experimentell erzeugter anterograder Degeneration der Verlauf von Axonen antennaler Rezeptorzellen im Oberschlundganglion verfolgt. Nach Abtrennen einer Antennengeisel (die beiden proximalen Segmente bleiben intakt) findet man degenerierte Nervenfortsatze in den Glomeruli des ipsilateralen Deutocerebrum. Bei Calliphora laufen viele dieser Axone uber eine Bahn dorsal des Oesophagus in die Glomeruli des contralateralen Deutocerebrum. Ein groser Ast des Antennennerven Calliphora zieht vorbei an der Region der Glomeruli in posteriore Regionen des Oberschlundganglions. Nach Abtrennen der ganzen Antenne einschlieslich der proximalen Segmente findet sich in diesem Trakt eine grose Zahl degenerierter Axone. Die Synapsen in der Region der Glomeruli ahneln anderen Synapsen, wie sie im Zentralnervensystem von Insekten bisher beschrieben wurden.
100 citations
TL;DR: Biopsies of marginal gingiva obtained still attached to extracted premolars 6–24 months after onset of tooth eruption from 10 children were processed according to standardized electron microscopic techniques and there was no statistically significant correlation between any of these parameters, and the % V VL and A I were not related to the time since onset of Tooth eruption.
99 citations
TL;DR: The conclusion seems warranted that the ballooning of synaptic vesicles is an early sign of terminal degeneration, it appears to precede vesicular disintegration.
Abstract: The terminal degeneration of retino-tectal fibres was studied electron microscopically in the pigeon Synaptic vesicles seem to undergo systematic changes which can best be observed in aldehyde-fixed material. Initially (i.e. within 12-24 h) the vesicles begin to swell. The enlargement is clearly visible after 4 days (40 % increase in diameter) and reaches a maximum at 14 days (100% increase). At the latter stage, the enlargement is almost invariably associated with the well known opacity of degenerating terminals. In contrast, normal control tissue contains nerve endings with only a few enlarged and no ballooning vesicles. The conclusion seems warranted that the ballooning of synaptic vesicles is an early sign of terminal degeneration, it appears to precede vesicular disintegration.
96 citations
TL;DR: In this article, it was shown that unsymmetrically substituted ketenes add to cyclopentadiene in such a manner that the larger substituent has a greater tendency to take up the endo-position in the adduct.
Abstract: Earlier work has shown that the cyclo-addition of a ketene to a conjugated diene is always (a) 2 + 2, (b) polarily directed, and (c) suprafacial with respect to the diene CC. The adducts of ketenes and cyclopentadiene are thus always 7-substituted bicyclo [3.2.0] hept-2-ene-6-ones. New evidence is presented to show that unsymmetrically substituted ketenes add to cyclopentadiene in such a manner that the larger substituent has a greater tendency to take up the endo- position in the adduct. This is interpreted to mean that a ketene participates in such reactions antarafacially. Thus the ketene approaches cyclopentadiene (a) with its functional plane perpendicular to that of the ring, (b) with the carbonyl carbon over the middle of the ring, and (c) with the larger of the two substituents oriented preferentially away from the ring (transition state 11).
This endo-specificity for the larger ketene substituent is demonstrated by the indicated endo/exo ratios observed in the cyclo-adducts from ketenes with the following substituent pairs: C6H5/H = >95/ 95/ 95/ 95/<5, CH3/Cl = 80/20, CH3/CHCH2 = ∼65/35, C2H5/CH3 = ∼60/40, n-C3H7/CH3 = ∼60/40, CH3/Br = 56/44.
These ratios enable a list to be compiled indicating the endo-specificity of the ketene substituents. The order closely parallels the space filling capacity as derived by other methods.
The establishment of such ratios required reliable configurational assignments at carbon 7. These were derived by five methods based upon the following effects: (1) Both HC7 and CH3C7 cause nmr. signals at higher field in endo-position (compared with exo). (2) The CH3C7 group in exo-position gives rise to a nuclear Overhauser effect with the vicinal HC1, and in one case also with the trans-annular HC5. (3) The nmr.-coupling constants of HC7-exo (observed at HC7) with HC1 is always larger than of HC7-endo. (4) The coupling constant of HC7-exo with HC6 (known to be exo-) of the LiAlH4 reduction products of the cyclo-adducts (observed at HC6) is always larger than that of HC7-endo. (5) The nmr. signals of most protons in the cyclo-adducts are at higher field in benzene than in chloroform solution; this “benzene shift” is larger for HC7 or for CH3C7 when in exo- than when in endo-position.
89 citations
TL;DR: Artificial cyanmet intermediates of haemoglobin were obtained by mixing cyanmet chains with their oxygenated partners and the alkaline Bohr effect is very similar for the two intermediates, but the acid BohR effect is lacking in (α + β+ CN).
83 citations
TL;DR: Decortication is strongly recommended as a means of treating osteomyelitis of the jaws as it arrested the symptoms of the disease and complete healing was encountered in patients with acute/subacute or secondary chronic osteomyelsitis.
TL;DR: Das entstehende Fe3+ bildet sofort ein (FeOOH)-Mikropräzipitat, welches bald so gross ist, dass es nicht mehr durch die Lücken der Apoferritinhohlkugel entweichen kann.
Abstract: Es wurde eine neue Hypothese fur die Eisenaufnahme durch Ferritin experimentell gepruft. Es scheint, dass die zweiwertigen Eisenionen in die Apoferritinhohlkugel eindringen konnen und im Innern an histidinhaltigen aktiven Stellen katalytisch oxydiert werden; das entstehende Fe3+ bildet sofort ein (FeOOH)-Mikroprazipitat, welches bald so gross ist, dass es nicht mehr durch die Lucken der Apoferritinhohlkugel entweichen kann.
TL;DR: Electron-microscopic investigations of the spinal cord in adult chickens poisoned with TOCP show pathological alterations as early as the first day after appearance of the clinical symptoms, attributed to axo-somatic synapses.
Abstract: Electron-microscopic investigations of the spinal cord in adult chickens poisoned with TOCP (Tri-Ortho-Cresyl Phosphate) show pathological alterations as early as the first day after appearance of the clinical symptoms. Of the same qualitative order as in the peripheral nervous system, they refer to the nerve fibres in the white matter in form of primarily diseased axons, with proliferation of the endoplasmic reticulum and disintegration of the neurofilaments. In the grey substance of the anterior horn, in particular, one sees severe structural alterations in the boutons terminaux while the motoneurons are hardly modified. The most striking finding already in the early stage is a massive swelling of the spherical synaptic vesicles in the boutons of theS-type, attributed to axo-somatic synapses.
TL;DR: Quantitative evaluation of other chromatographic peaks on the analyser demonstrated that 8-day-old female flies contain twice as much free methionine as males of the same age, and the content of β-alanine amounts to about 50% higher in male than in female adults.
TL;DR: The 3-C-hydroxymethylriburonic acid, isolated as one of the components of the hexuronosylhexuronide, is the first natural branched-chain hexuronic Acid to be detected, and the first branches-chain sugar ever detected in humans.
Abstract: Structure elucidations have been performed on the bilirubin conjugates isolated from human hepatic bile as the phenylazo derivatives. The major bilirubin conjugates are excreted, not as was formerly thought in the form of glucuronides, but as the acyl glycosides of aldobiouronic acid, pseudoaldobiouronic acid and hexuronosylhexuronic acid. The isolated aldobiouronides are proposed to have the structures of an acyl 6- O -hexopyranosyluronic acid-hexopyranoside, an acyl 4- O -hexofuranosyluronic acid-d-glucopyranoside, and an acyl 4- O -β-d-glucofuranosyluronic acid-d-glucopyranoside respectively, with the acyl radicals being those of the phenylazo derivative of bilirubin. The pseudoaldobiouronide is suggested to be the acyl 4- O -α-d-glucofuranosyl-β-d -glucopyranosiduronic acid, with the acyl radical being that of the phenylazo derivative of vinylneoxanthobilirubinic acid. The hexuronosylhexuronide presumably is the acyl 4- O -(3- C -hydroxymethylribofuranosyluronic acid)-β-d-glucopyranosiduronic acid, with the acyl radical being that of the phenylazo derivative of bilirubin. The 3- C -hydroxymethylriburonic acid, isolated as one of the components of the hexuronosylhexuronide, is the first natural branched-chain hexuronic acid to be detected, and the first branched-chain sugar ever detected in humans.
TL;DR: The type of sampling used for the present study is suitable for comparative morphometric studies and differences were markedly smaller than those between comparable strata of both epithelia.
Abstract: SUMMARY
Stereologic point-counting procedures were applied to estimate quantitative tissue and cytoplasm parameters of the oral and the junctional epithelium of the human gingiva. Three gingival biopsies of female children, obtained and processed under standardized conditions, served (1) to determine the minimal sample size of cytoplasmic area required for estimating representative volumetric parameters in different strata of both epithelia, and (2) to compare average volume and surface density data derived from standardized samples in epithelial cross sections cut at two planes orientated perpendicular to each other. Sampling of electron micrographs, performed at two levels of magnifications according to a systematic stratified random sampling procedure consisted of recording field strips parallel to the epithelial or tooth surface within each of the various strata. The optimal sample size required varied for different organelles and epithelial strata. Minimal sample size of cytoplasmic area per biopsy were 300–440 μm2 for basal, and 450 μm2 for stratum spinosum cells of oral epithelium, and 130–185 μm2 for basal cells of the junctional epithelium. Average morphometric parameters for gross tissue components (cells, nuclei, cytoplasm, intercellular space) which resulted from analysing 4900 μm2 tissue area in each of the epithelia in each biopsy, were almost identical when determined in two different section planes. Volume and surface density data of cytoplasmic organelles (mitochondria, rough and smooth endoplasmic reticulum, cytoplasmic filaments) resulting from a sample of 280 μm2 cytoplasmic area per stratum and biopsy, revealed differences of varying magnitude, when determined in the two section planes. These differences were markedly smaller than those between comparable strata of both epithelia. Discussion of sampling procedures concluded that the type of sampling used for the present study is suitable for comparative morphometric studies.
TL;DR: The present data suggest that the intrinsic contractile state of the myocardium of the left ventricle is impaired in patients with left ventricular hypertrophy from aortic stenosis but without heart failure.
TL;DR: Topically applied retinoic acid induces partial or complete clinical regressions of senile or actinic keratoses as well as of basal cell carcinomas of the skin in patients with premalignant and malignant lesions.
Abstract: Topically applied retinoic acid induces partial or complete clinical regressions of senile or actinic keratoses as well as of basal cell carcinomas of the skin. 15 out of 16 treated basal cell carcinomas regressed by more than 50%, regressions being complete in 5 cases. The mode of action of retinoic acid on premalignant and malignant lesions is discussed.
TL;DR: The patient shows some unusual features compared to the classic description of the syndrome: the external genitalia are normal, the predominant 17-ketosteroid was androsterone and not dehydroepiandrosterone, and pregnanetriol was present.
Abstract: The case of a girl, aged 6 1/2 yr, with probable 3β-hydroxysteroid dehydrogenase deficiency is described. To our knowledge, this is the second surviving patient with this condition. After ACTH administration, the predominant urinary steroid was Δ5-pregnenetriol. Δ5-Pregnenediol was also identified. Testosterone and pregnanetriolone were not detectable. The patient shows some unusual features compared to the classic description of the syndrome: the external genitalia are normal, the predominant 17-ketosteroid was androsterone and not dehydroepiandrosterone, and pregnanetriol was present. Possible explanations of these findings are discussed.
TL;DR: In this article, the optical spectra of commercial and human bile bilirubin conjugates were recorded and the structure of the phenylazo derivatives of conjugate molecules was investigated.
Abstract: N.m.r., i.r. and optical spectra of model compounds were recorded. These were to help in elucidating the structures of the phenylazo derivatives of bilirubin conjugates isolated from human bile. Model compounds included commercial and human bile bilirubin, mesobilirubin, bilirubin dimethyl ester, dimethoxybilirubin dimethyl ester and the corresponding phenylazo derivatives. The phenylazo derivative of vinylneoxanthobilirubinic acid was also investigated. All compounds were of the type IXα, and no other isomer could be detected with the spectroscopic methods employed. The compounds crystallize as the lactams, except for dimethoxybilirubin dimethyl ester and its phenylazo derivative, which are held in the lactim ether configuration. With all other compounds no tautomeric forms other than the lactams could be detected, although small proportions of bilirubin must exist as the lactim. Bilirubin does not form a betaine, a structure that has been proposed by von Dobeneck & Brunner (1965) to explain the bathochromic shift of its optical spectrum as compared with the expected position of the absorption maximum at 420nm. However, this shift to 453nm can be explained on the basis of internal hydrogen bonds occurring between the carboxylic protons and the pyrrole rings of bilirubin, as proposed by Fog & Jellum (1963), and new evidence for such a bonding has been accumulated. The bilirubin sulphate described by Watson (1958), which is formed by treatment of bilirubin with concentrated sulphuric acid and acetic anhydride, was also investigated. The main product of this reaction was isolated as its phenylazo derivative, and was shown to be 3,18-di(ethylidene sulphate)-2,7,13,17-tetramethylbiladiene-ac-8,12-dipropionic acid. The reaction leading to this compound is an addition of sulphuric acid to the vinyl side chains of bilirubin according to Markownikoff's rule.
TL;DR: It is concluded that free, 3′-adenosineless Q β RNA is not an intermediate in Qβ synthesis and that only nascent Qβ RNA can serve as an acceptor for the 3′/3′-terminal pA.
TL;DR: Results indicate a zone specificity of certain stimulators and confirm that they act at an early stage in the corticosteroid biosynthetic pathway preceding the formation of deoxycorticosterone.
Abstract: Capsular and decapsulated adrenal glands of rats kept on different diets were separately incubated with and without stimulators of aldosterone biosynthesis. The steroidogenic effect of serotonin, potassium ions and angiotensin II was limited to the capsular portion (zona glomerulosa), whereas ACTH and cyclic AMP acted on both the capsular and the decapsulated portion (zona fasciculata-reticularis) of the adrenal cortex. In capsular adrenal glands of normal and sodium-deficient rats all these agents stimulated aldosterone production severalfold and had a smaller effect on corticosterone output. Sodium deficiency led to a decreased response in corticosterone and deoxycorticosterone output. In capsular glands of potassium-deficient rats the stimulators did not enhance aldosterone production but actsd mainly on deoxycorticosterone output. ACTH enhanced corticosteron e and deoxycorticosterone output to a similar extent in decapsulated glands of all groups of experimental animals. These results indicate a zone specificity of certain stimulators and confirm that they act at an early stage in the corticosteroid biosynthetic pathway preceding the formation of deoxycorticosterone. On the other hand, changes in sodium and potassium balance induce alterations in the activity of the enzymes involved in the conversion of deoxycorticosterone to aldosterone and thus influence the steroidogenic response of the zona glomerulosa to stimulating agents.
TL;DR: Ten mU of NSILA‐S injected intravenously stimulated the incorporation of [6‐14C] glucose into the diaphragm of streptozotocin‐diabetic rats to a much greater extent than 6mU of insulin, whereas their effects on the incorporationof carbon 14 into the fat pad were equal.
Abstract: 10 mU of NSILA-S, as determined by the fat pad assay, lowered blood glucose and free fatty acids of adrenalectomized rate for a much longer period than 10 mU of crystalline insulin. NSILA-S was not measurably inactivated by the liver during a 2 h cyclical perfusion, whereas insulin rapidly lost activity with a half-life of 42 min. 6 mU of NSILA-S injected intravenously stimulated the incorporation of [6-14C] glucose into the diaphragm of streptozotocin-diabetic rats to a much greater extent than 6 mU of insulin, whereas their effects on the incorporation of carbon 14 into the fat pad were equal.
When injected intraperitoneally in maximal doses to normal rats both agents stimulated the incorporation of [U-14C] glucose into adipose tissue and diaphragm to the same extent. There was no potentiation of either agent by the other on adipose tissue in vitro, indicating that they affect the same transport site of the cell membrane. Insulin and NSILA-S influenced the metabolism of adipose tissue of fasted-refed rats in the same manner.
It is concluded that i.v. injected NSILA-S is more effective in vivo than comparable doses of insulin because it is not inactivated by the liver. Furthermore, it seems to have a particular affinity to receptors of the muscle cell membrane. This may be an additional factor in protecting it from inactivation by other tissues.
TL;DR: The reproducibility of single determinations using the readings after 60-sec contact of a valinomycin liquid-membrane electrode with the sample is 0.07 mequiv/1 K+ (standard deviation).
TL;DR: The influence of the pericruciate cortex on 481 neurons of the contralateral LRN was studied in cats anesthetized with α-chloralose and about 80% of the neurons were excited by a cortical train stimulus.
TL;DR: Testosterone administration to normal male and female rats causes increased erythropoiesis and granulocytosis at the same time that bone marrow and thymus lymphocytic cellularity is being diminished as discussed by the authors.
TL;DR: The lung deflation reflex plays no part in the self-regulation of breathing and should be regarded as a nociceptive reflex tending to prevent and suppress pulmonary compression and pulmonary collapse.
TL;DR: Responses of single neurons of the lateral reticular nucleus (LRN) were investigated after stimulation of the red nucleus, of the fastigial nucleus, and of peripheral nerves in 42 cats anesthetized with chloralose to demonstrate the existence of monosynaptic excitatory pathways from both nuclei to the LRN which possibly end in two different groups of LRN neurons.
TL;DR: In this paper, the proton-NMR spectra of amino- and hydroxypyrimidines including biologically important bases have been measured in four solvents: CF3COOH, CF3cOOHSO2, FSO3H and FSO-3HSbF5-SO2 at 27° and −55°C.
Abstract: Proton-NMR. spectra of amino- and hydroxypyrimidines including biologically important bases have been measured in four solvents: CF3COOH, CF3COOHSO2, FSO3H and FSO3HSbF5–SO2 at 27° and −55°C. In CF3COOH mono-cations are formed, whereas in FSO3H and FSO3HSbF5–SO2 double protonation occurs. In each case the structures of the protonated species are derived from the chemical shifts of CH, NH and OH protons and proton-proton spin coupling constants. A combination of the measurements described leads to a complete assignment of all proton resonances of the protonated pyrimidines. This approach is also recommended for the structural determination of heterocyclic compounds.