Showing papers by "University of Milan published in 1977"
TL;DR: The mechanical power spent to accelerate the limbs relative to the trunk in level walking and running, Ẇint, has been measured at various ‘constant’ speeds with the cinematographic procedure used by Fenn (1930a) at high speeds of running.
Abstract: 1. The mechanical power spent to accelerate the limbs relative to the trunk in level walking and running, W(int), has been measured at various ;constant' speeds (3-33 km/hr) with the cinematographic procedure used by Fenn (1930a) at high speeds of running.2. W(int) increases approximately as the square of the speed of walking and running. For a given speed W(int) is greater in walking than in running.3. In walking above 3 km/hr, W(int) is greater than the power spent to accelerate and lift the centre of mass of the body at each step, W(ext) (measured by Cavagna, Thys & Zamboni, 1976b). In running W(int) W(ext).4. The total work done by the muscles was calculated as W(tot) = W(int) + W(ext). Except that at the highest speeds of walking, the total work done per unit distance W(tot)/km is greater in running than in walking.5. The efficiency of positive work was measured from the ratio W(tot)/Net energy expenditure: this is greater than 0.25 indicating that both in walking and in running the muscles utilize, during shortening, some energy stored during a previous phase of negative work (stretching).6. In walking the efficiency reaches a maximum (0.35-0.40) at intermediate speeds, as may be expected from the properties of the contractile component of muscle. In running the efficiency increases steadily with speed (from 0.45 to 0.70-0.80) suggesting that positive work derives mainly from the passive recoil of muscle elastic elements and to a lesser extent from the active shortening of the contractile machinery. These findings are consistent with the different mechanics of the two exercises.
771 citations
TL;DR: In this article, a deep-sea core over 16 m long from the crestal area of the Mediterranean Ridge has been investigated with different techniques, including quantitative micropaleontology, stable isotopes (measured on the epipelag species Globigerinoides ruber and on the mesopelagic species Globorotalia inflata), and clay mineralogy.
347 citations
TL;DR: The hypothesis that a soy protein has a hypocholesterolaemic action per se is supported by the results of a subsequent experiment in 8 type-II patients in whom the addition of cholesterol (500 mg/day) to soy protein did not modify the hypocholesterololaemic response.
308 citations
TL;DR: In this article, the depletion of δ18O in many of the sapropels is accompanied by the occurrence of poorly diversified planktonic faunas, and both phenomena are attributed to a strong dilution of the local eastern Mediterranean surface water mass by a combination of glacial run off from large continental ice sheets and by an important increase of regional precipitation synchronous with the transition from pleniglacial to kataglacial climate.
271 citations
TL;DR: Oral or sublingual administration of nifedipine (10 mg), a new coronary dilator, induced a prompt and large pressure reduction in patients with severe primary hypertension, mediated through diminished peripheral resistance associated with rise of cardiac output and pulse rate.
Abstract: Oral (17 cases) or sublingual (9 cases) administration of nifedipine (10 mg), a new coronary dilator, induced a prompt and large pressure reduction in patients with severe primary hypertension. Pressure started to fall within 20 and 5 min after oral and sublingual administration, respectively, and reached the lowest levels in the next 10 min. Maximal mean arterial pressure reduction averaged 36 mm Hg; 120 min after the drug, mean arterial pressure was diminished by 19.5% of control. The hypotension was mediated through diminished peripheral resistance associated with rise of cardiac output and pulse rate. Nifedipine was also administered siblingually in 3 cases with hypertensive encephalopathy and acute left ventricular failure with average systemic and pulmonary arterial pressures from 307/164 and 91/55 mm Hg, respectively, which fell to 237/115 and 68/35 mm Hg 15 min after 10 mg of the drug, and were further reduced to 176/89 and to 47/19 mm Hg by an additional 10 mg.
236 citations
TL;DR: The sedimentary products of euxinification are organic-rich sapropels which have accumulated an order of magnitude more carbon during the Cretaceous than that which is present in all the known world reserves of coal and petroleum as discussed by the authors.
209 citations
TL;DR: Phonemic identification defect (PID), defined with reference to the performance of the control group, was found to be virtually limited aphasics; some evidence pointed to disordered phonemic output as to one dimension of aphasia that is specifically related to it.
152 citations
TL;DR: The results suggest that dopamine, released from nigral dendrites, may influence dopaminergic activity indirectly by modulating impulses transmitted to the nigrostriatal neurons through the crus cerebri.
Abstract: Nigral basal adenylate cyclase and dopamine-sensitive adenylate cyclase, glutamate decarboxylase, choline acetyltransferase, and tyrosine hydroxylase activities were measured in rats with hemitransections at various levels or with electrolytic lesions of the medial forebrain bundle or the crus cerebri. The loss of nigral dopamine-sensitive adenylate cyclase activity after the various brain lesions was correlated with loss of nigral glutamic acid decarboxylase but not that of tyrosine hydroxylase; nigral choline acetyltransferase was unaffected in all cases. The data indicate that the nigral dopamine-sensitive adenylate cylase activity may be localized on neurons afferent to the nigra, probably originating from the globus pallidus and possibly from the tail of the caudate. The results suggest that dopamine, released from nigral dendrites, may influence dopaminergic activity indirectly by modulating impulses transmitted to the nigrostriatal neurons through the crus cerebri.
151 citations
TL;DR: It is concluded that the variable-pressure neck chamber is a valid method for selectively studying the carotid baroreceptor reflex in man, however, transmission of external pneumatic pressure to theCarotid sinus is imperfect and greater for positive than for negative pressure.
Abstract: 1. The variable-pressure neck-chamber method was analysed in ten healthy volunteer subjects to determine its suitability for the study of the carotid baroreceptor reflex in man. 2. Positive and negative pressures applied to the neck (range ± 60 mmHg) were always transmitted linearly to a tissue catheter outside the carotid sinus, but only 86% of positive pressure, and 64% of negative pressure. Tissue pressures were confirmed by simultaneous measurement in the internal jugular vein adjacent to the carotid sinus. 3. Positive and negative pressure changes within the above range did not alter P o 2 of internal jugular venous blood, suggesting that cerebral blood flow was unaltered. 4. Positive pressure changes induced reflex pressor responses of similar magnitude at arterial P o 2 12·8 and 70·1 kPa (96 and 527 mmHg), suggesting that the carotid chemoreceptors were not involved. 5. It is concluded that the variable-pressure neck chamber is a valid method for selectively studying the carotid baroreceptor reflex in man. However, transmission of external pneumatic pressure to the carotid sinus is imperfect and greater for positive than for negative pressure. This must be recognized to avoid underestimation of gain and distortion of shape of the reflex.
142 citations
TL;DR: The carotid sinus baroreceptor reflex of the normotensive man is an effective antihypotensive and antihypertensive feedback system, though the former function may have more sensitivity.
Abstract: The carotid sinus baroreceptor reflex was studied in 11 normotensive subjects, using a variable pressure neck chamber and correcting for imperfect pressure transmission to the carotid sinus. Decreased carotid baroreceptor stimulation caused a sustaineded rise in arterial pressure, and increased carotid baroreceptor stimulation caused a sustain fall. The responses were in linear relation to the stimulus, and, after reaching the steady state, greater for the reduced than for the increased baroreceptor stimulation. Thus the carotid sinus baroreceptor reflex of the normotensive man is an effective antihypotensive and antihypertensive feedback system, though the former function may have more sensitivity. The increased and decreased baroreceptor stimulation by the neck chamber also caused bradycardia and tachycardia which were modest in magnitude and often transient. In eight subjects the reflex changes in heart rate induced by the neck chamber were compared with those induced by altering transmural pressure not merely at the carotid sinus but throughout the arterial tree (injection of phenylephrine and trinitroglycerin). The slopes of these relations were 3 times as great in the latter circumstance. Thus the carotid baroreceptors play a lesser role in heart rate control than do extracarotid baroreceptors.
132 citations
TL;DR: Zein extracted from maize endosperm has been fractionated into four polypeptide chains, having the following MWs 23 000, 21 000, 13 500 and 9600, and by amino acid analysis the two smaller MW chains (representing 30% of total zeins) have been found to be zein-type molecules.
TL;DR: In this article, a search for γ-ray sources using data from the ESA γray satellite COS B revealed 10 new unknown sources with a luminosity in excess of 1035 erg s−1.
Abstract: LOCALISED γ-ray sources contribute to the overall galactic emission; some of these sources have been identified with known astronomical objects1,2, while several unidentified γ-ray sources have also been reported3,4. We describe here a search for γ-ray sources using data from the ESA γ-ray satellite COS B which revealed 10 new unidentified sources. These sources seem to be galactic with typical γ-ray luminosities above 100 MeV in excess of 1035 erg s−1.
TL;DR: It is concluded that the observed zein heterogeneity is partly based on in vivo deamidation of glutamine and asparagine and partly to spot mutations in some of the genes responsible for zein synthesis.
Abstract: The extensive charge heterogeneity of maize (Zea mays L.) zeins observed in isoelectric focusing (IEF) (about 15 bands with pI's in the pH range 6-9) has been found to be independent of extraction proce- dures or of endosperm development. Zeins do not stain for glycoproteins and exhibit only one lipo- protein component, with pI 3, representing 3-5% of the total protein. Zeins are very resistant to in vitro deamidation, at both acidic and alkaline pH, at high temperatures, and for rather prolonged times. On the basis of the zein content in acidic and basic amino acids, and of the respective pI's exhibited in IEF (mostly in the pH range 7-8) it has been calculated that at least 90% of the glutamic and aspartic acids ( ~ 52 residues out of a total of ~190) are present as asparagine and glutamine. Amino acid analysis of zein fractions isolated by preparative IEF has demonstrated changes in the composition of 18 amino acid residues. However, since these changes affect only neutral and hydropho- bic residues, it is concluded that the observed zein heterogeneity is partly based on in vivo deamidation of glutamine and asparagine and partly to spot muta- tions in some of the genes responsible for zein syn- thesis.
TL;DR: An exaggerated and sustained PRL rise was present after TRH in the subjects with liver disease, whose mean baseline plasma PRL levels were within normal range, while mean baseline GH levels wre higher in patients than in controls.
Abstract: Thyrotropin-releasing hormone (TRH) was administered iv to 10 patients with severe liver disease and 10 control subjects. Injection of 400 microgram TRH as a bolus induced in 7 out of 10 patients a clear-cut GH rise (larger than or equal 10 ng/ml) occurring 15-120 min after the injection, and no effect on GH levels in controls. Mean baseline GH levels wre higher in patients than in controls. An exaggerated and sustained PRL rise was present after TRH in the subjects with liver disease, whose mean baseline plasma PRL levels were within normal range.
TL;DR: The high risk values obtained for affective disorders were shown to be compatible with those found by other authors, although the prevalence of the illness in the population of Lombardy appears to be much lower than in other countries.
Abstract: First and second degree relatives of 99 probands with affective disorders (49 unipolar and 50 bipolar subjects) were studied. The high risk values obtained for affective disorders were shown to be compatible with those found by other authors, although the prevalence of the illness in the population of Lombardy appears to be much lower than in other countries. Very low rates of suicide and alcoholism were found in our sample. Data obtained by analysis of the affected pairs of relatives rule out the hypothesis of a dominant X-linked gene if the bipolar and the unipolar forms are considered genetically separated entities. Results compatible with a polygenic condition, partially shared by bipolar patients, were found using Slater's and Smith & Falconer's methods. Our data, however, cannot rule out the dominant hypothesis. Language: en
TL;DR: Three patients affected by a progressive myopathy with rapid lethal evolution are presented, and excessive lipid storage was found in type 1 fibres of muscle and in liver, kidney, and myocardium.
Abstract: Three patients affected by a progressive myopathy with rapid lethal evolution are presented. Excessive lipid storage was found in type 1 fibres of muscle and in liver, kidney, and myocardium. Carnitine concentrations were markedly reduced in muscle, plasma, and heart, significantly lower in the liver, and normal in kidney. D-L carnitine replacement therapy was ineffective in the only case treated. The relationship of the present cases with the syndrome of lipid storage myopathy and carnitine deficiency is discussed.
TL;DR: The upper Santonian to upper Paleocene pelagic sequence at Gubbio, Italy, yields a remarkably continuous succession of rich planktic foraminiferal faunas.
Abstract: The upper Santonian to upper Paleocene pelagic sequence at Gubbio, Italy, yields a remarkably continuous succession of rich planktic foraminiferal faunas. Seven zones are recognized in sediments of the Late Cretaceous period: Globotruncana concavata carinata , G. elevata , G. calcarata , G. tricarinata , G. gansseri , G. contusa , and Abathomphalus mayaroensis , and the Paleocene is represented by “ Globigerina” eugubina , Globorotalia pseudobulloides , G. trinidadensis , G. uncinata , G. angulata , G. pusilla pusilla , and G. pseudomenardii . These zones provide the biostratigraphic framework for the geomagnetic reversal sequence observed in the same section.
TL;DR: Freeze-fracture has confirmed the presence of desmosomes, gap junctions, and tight junctions in fixed human epidermis as discussed by the authors, showing that the area occupied by the junctions is at a different level than that of the adjacent nonjunctional membrane.
TL;DR: Morphine, intracerebroventricularly or intraperitoneally administered to rats, inhibited intestinal propulsion as tested by a charcoal meal, shown to be linearly related to the log of administered doses for both routes of administration and the two linear regressions are parallel, so that morphine was calculated to be 206 times more potent when administered i.c.v. than i.p. routes.
TL;DR: Fusicoccin, a diterpene glucoside very active in stimulating proton/K + exchange in higher plant tissues, is shown to increase in vitro the K + Mg 2+ -stimulated ATPase activity of plasmalemma-enriched membrane preparations from maize coleoptiles and from spinach leaves.
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TL;DR: The phytochemical components of olive oil include fatty acid,glyceride, phospholipids, and triterpenes, which are composed of fatty acid esters, glucose, phosphate, and alcohol.
Abstract: Il. LIPID CONTENT OF OLMS A. Fatty acid composition of olive oil B. Glyceride composition of olive oil C. Nonglyceridic components of olive oil I. Hydrocarbons 2. Fatty acid esters 3. Tocopherols 4. Aliphatic alcohols 5. Monohydroxy triterpenes 6. 4a-Methylsterols 7. Sterols 8. Dihydroxy triterpenes 9. Hydroxy triterpenic acids IO. Chlorophylls 1 I. Phospholipids D. Flavoring components of olive oil
TL;DR: The changes in structure of the plasmalemma and intercellular junctions of rat oral epithelium have been investigated by freeze-fracture and lanthanum impregnation after in vitro treatment of mucosal strips with trypsin support the idea that desmosomes are complex structures composed of cytoplasmic, membranous and extracellular components.
TL;DR: Results indicate that: 1) Leu5-enkephalin stimulates both GH and PRL release; 2) the release of GH by Leu4-enkphalin but likely not that of PRL involves specific opiate receptors; 3) morphine releases GH andPRL through specific opiates receptors.
TL;DR: Differential centrifugation and isopycnic sucrose density gradients with parallel determination of markers indicate the localization of the FC binding sites at the plasmalemma, in agreement with the known in vivo effects of this fungal toxin.
TL;DR: Stimulation of juxtaglomerular cells by tilting is entirely due to sympathoadrenergic activation; stimulation by furosemide is also entirely neural when the diuretic drug is given in moderate doses, but is partly independent of innervation when larger doses are administered.
Abstract: In anesthetized cats head-up tilting for 30 min and infusion of furosemide at 0.75 mg/kg in 30 min significantly raised renin release from the innervated kidney (increments of 90.7 +/- 21.4 ng/min on tilting and 105.4 +/- 26.4 ng/min after furosemide); a small and inconstant increase from the contralateral denervated kidney (increments of 16.8 +/- 16.0 and 16.3 +/- 17.7 ng/min, respectively) was abolished by acute bilateral adrenalectomy. Larger doses of furosemide (6.0 mg/kg) could release renin from the denervated kidney also, but the response was still more marked on the innervated side especially in the early period of infusion (increments of 132.7 +/- 23.8 and 33.7 +/- 23.8 ng/min of innervated and denervated sides at 10 min). The response of the denervated kidney to 6.0 mg furosemide/kg was not affected by adrenalectomy. Stimulation of juxtaglomerular cells by tilting is entirely due to sympathoadrenergic activation; stimulation by furosemide is also entirely neural when the diuretic drug is given in moderate doses, but is partly independent of innervation when larger doses are administered.
TL;DR: Administration of baclofen, 30 mg daily for 4 days, caused a significant reduction of GH response to hypoglycemia and arginine infusion, respectively, and the response of PRL to the above stimuli was increased after bacl ofen administration.
Abstract: In 2 groups of 6 normal subjects each, we have investigated the effects of oral administration of a gamma aminobutyric acid (GABA) derivative, baclofen [β-(4-chlorophenyl)-gamma aminobutyric acid, Lioresal, Ciba-Geigy] on growth hormone (GH) and prolactin (PRL) secretion in response to insulin hypoglycemia and arginine infusion, respectively. Administration of baclofen, 30 mg daily for 4 days, caused a significant reduction of GH response to hypoglycemia (mean peak values decreased from 30.7 ± 6.30to 21.5 ± 5.74 ng/ml, P < 0.01) and to arginine infusion (21.8 ± 2.94 vs. 13.6 ± 2.16 ng/ml, P < 0.05). In contrast, the responseof PRL to the above stimuli was increased after baclofen administration: mean peak plasmalevels increased from 22.0 ± 4.01 to 30.1 ± 3.85 ng/ml, P < 0.05, in the insulin tolerance test, and from 22.6 ± 4.83 to 36.7 ± 6.60 ng/ml, P < 0.05, after arginine infusion. The pattern of plasma free fatty acids (FFA) and blood glucose was not changed by baclofen treatment during either of the te...
TL;DR: It is concluded that the inhibition of photosynthesis by CN(-) and N(3) (-) is due to H( 2)O(2) accumulation, which is a consequence of catalase inhibition.
Abstract: Cyanide and azide inhibit photosynthesis and catalase activity of isolated, intact spinach (Spinacia oleracea) chloroplasts. When chloroplasts are illuminated in the presence of CN(-) or N(3) (-), accumulation of H(2)O(2) is observed, parallel to inhibition of photosynthesis. Photosynthetic O(2) evolution is inhibited to the same extent, under saturating light, whether CO(2) or phosphoglycerate is present as electron acceptor.The illumination of chloroplasts with CN(-) or N(3) (-) inactivates the NADPH- and ATP-dependent phosphoglycerate reduction. This enzyme system can be reactivated by dithiothreitol. In reconstituted, envelope-less chloroplasts, the phosphoglycerate-dependent and the ribose 5-phosphate-dependent O(2) evolution are inhibited to the same extent, while electron transport to NADP is unaffected.It is concluded that the inhibition of photosynthesis by CN(-) and N(3) (-) is due to H(2)O(2) accumulation, which is a consequence of catalase inhibition.The inhibition of phosphoglycerate reduction, but not of CO(2) reduction, is abolished under conditions where ATP is available in excess of NADPH (low light, supply of ATP). This is taken as an indication that electron flow from photosystem I is diverted to O(2) (Mehler reaction, which produces H(2)O(2)) when the unavailability of ATP is limiting the rate of reoxidation of NADPH. The Mehler reaction is considered a physiological process supplying ATP for photosynthesis.
TL;DR: The functional status of dopaminergic nerve terminals has been studied with a method that allows the simultaneous determination of the specific activities of dopamine, tyrosine, 3‐methoxytyramine and 3,4‐dihydroxyphenylacetic acid after administration of [3H]tyrosine.
Abstract: —
The functional status of dopaminergic nerve terminals has been studied with a method that allows the simultaneous determination of the specific activities of dopamine (DM), tyrosine (Tyr), 3-methoxytyramine (3-MT) and 3,4-dihydroxyphenylacetic acid (DOPAC), after administration of [3H]tyrosine ([3H]Tyr).
Combined fluorimetric, mass fragmentographic and radiometric techniques have been used. [3H]Tyrosine was given intraventricularly to unanaesthetized rats and the animals were killed by exposure for 4 s to high energy microwave radiations.
The specific activities of 3-MT and DOPAC measured 5 and 20 min after administration of [3H]Tyr, i. e. at time intervals in which the specific activity of DM is rising, are much higher than those their physiological precursor, suggesting that they are generated by more than one DM compartment.
This hypothesis seems to be supported by the finding that in animals killed by decapitation instead of microwave radiations the post mortem accumulation of 3-MT occurs to a much smaller extent for the radioactive fraction than for the endogenous one, indicating that 3-MT formed after death may be mainly derived from DM coming from a compartment where this monoamine has been poorly labeled by the radioactive precursor.
TL;DR: Tumours of the fifth cranial nerve are very rare, comprising only 0.2% of all intracranial neoplasms, and as a consequence they usually reach a large size before causing sufficient symptoms to lead the patient to a neurosurgical clinic.
Abstract: Tumours of the fifth cranial nerve are very rare, comprising only 0.2% of all intracranial neoplasms.