Showing papers by "University of Milan published in 1983"

Blood pressure and heart rate variabilities in normotensive and hypertensive human beings.

Abstract: Blood pressure and heart rate variabilities were studied in 89 ambulant normotensive or essential hypertensive subjects in whom blood pressure was recorded intra-arterially for 24 hours (Oxford method) under standardized living conditions. Data were analyzed beat to beat by a computer to provide mean values of the 48 half hours of the 24-hour period. Variabilities were assessed by the standard deviation and variation coefficients separately obtained for each half hour, as well as by the standard deviations and variation coefficients obtained by averaging the 48 mean values. In each subject, blood pressure and heart rate varied markedly either among or within half hours, indicating the existence of relatively longand short-term variabilities during the 24 hours. When averaged for all subjects, the long-term variabilities showed only one systematic component, i.e., the marked reduction occurring during sleep. Sleep was further responsible for a marked reduction in the short-term blood pressure and heart rate variabilities. These variabilities showed marked (though nonsystematic) modifications, even outside sleep, which were positively related to the blood pressure and heart rate means. Modifications in blood pressure and heart rate means and short-term variabilities were also positively related to each other. All these features were common to normotensives and hypertensives. In hypertensives, the absolute long and short-term blood pressure variabilities were greater than in normotensives, but the percent blood pressure variabilities were similar. Heart rate variabilities (both absolute and percent) were similar in normotensive and hypertensive subjects. Heart rate variabilities were also similar whether the subjects had impaired or preserved baroreflex control of heart rate (vasoactive drug technique). These findings uncover a number of factors that are associated with and responsible for blood pressure and heart rate variabilities in human beings. The nature of these factors suggest a primary role of central nervous mechanisms in the production of these phenomena and in the overall cardiovascular modulation, with no substantial difference between conditions of normal and chronically elevated blood pressure. (Circ Res 53: 96-104, 1983)

Deamino-8-D-Arginine Vasopressin Shortens the Bleeding Time in Uremia

Abstract: In a randomized double-blind cross-over trial we gave either 1-deamino-8-D-arginine vasopressin or placebo to 12 patients with uremia, hemorrhagic tendencies, and prolonged bleeding times. After vasopressin infusion, all patients had shortened bleeding times, with the effect lasting for at least four hours in most cases. Platelet count, platelet cyclic AMP levels, platelet retention on glass beads, plasma fibronectin, serum thromboxane B2 and residual prothrombin, hematocrit, and plasma osmolarity were unchanged after vasopressin. A consistent post-infusion increase in factor VIII coagulant activity and, to a lesser extent, in factor VIII-related antigen and ristocetin cofactor accompanied the shortening of bleeding time. In addition, vasopressin induced the appearance in plasma of larger von Willebrand-factor multimers than those present in the resting state. The compound was given to nine additional patients with acute or chronic renal failure and prolonged bleeding times, before major surgery or renal biopsy. In these patients, shortening of the bleeding time was associated with normal hemostasis. Our findings indicate that 1-deamino-8-D-arginine vasopressin can be used for temporary correction of bleeding time and may prevent surgical bleeding in patients with uremia.

Efficient direct chromosome analyses and enzyme determinations from chorionic villi samples in the first trimester of pregnancy

Abstract: Chorionic villi were obtained by an aspiration technique which proved to be the best of four alternative procedures. We report in detail the series of experiments which led to (1) successful, rapidly growing cell cultures practically free of maternal cell contamination (the use of hormone-supplemented Chang medium greatly increased the growth rate); (2) an efficient direct method to obtain high quality metaphases from the Langhans cells of the cytotrophoblast tissue and with which the fetal karyotype is defined within a few hours of chorionic villi sampling; and (3) successful testing for the activity of eight enzymes directly from the villi samples, thus showing that this material is suitable for a rapid, direct diagnosis of the related metabolic diseases.

Regulation of the macrophage content of neoplasms by chemoattractants.

Abstract: Factor chemotactic for mononuclear phagocytes was found in supernatant fluids of cultured human and mouse tumor cells In 11 mouse tumors there was a correlation observed between chemotactic activity and macrophage content of neoplastic tissues Tumor-derived chemoattractants appear to participate in the regulation of tumor-associated macrophages

Arterial Baroreflexes in Humans

Abstract: The sections in this article are: 1 Techniques 1.1 Carotid Sinus Massage 1.2 Electrical Stimulation of Carotid Sinus Nerves 1.3 Section or Anesthesia of Carotid Sinus Nerves and Vagi 1.4 Occlusion of Common Carotid Arteries 1.5 Neck Chamber 1.6 Vasoactive Drugs 1.7 Nonselective Techniques 2 Arterial Baroreceptor Control of Heart Rate 2.1 Autonomic Mediation 2.2 Other Properties 2.3 Relationship to Base-Line R-R Interval 2.4 Relationship to Respiratory Cycle 3 Arterial Baroreceptor Control of Atrioventricular Conduction and Ventricles 4 Carotid Baroreceptor Control of Blood Pressure 5 Carotid Baroreceptor Influence on Cardiac Output and Total Peripheral Resistance 6 Arterial Baroreceptor Control of Regional Circulations 7 Arterial Baroreceptor Control of Veins 8 Set Point of Carotid Baroreflex 9 Aortic Baroreflexes 10 Factors That Modify Arterial Baroreceptor Control of Circulation 10.1 Age 10.2 Exercise 10.3 Mental Stress 10.4 Sleep 10.5 Anesthesia 10.6 Central Blood Volume and Posture 11 Pathological States 11.1 Hypertension 11.2 Heart Disease 11.3 Carotid Sinus Syndrome 11.4 Other Pathological Conditions 12 Modification of Arterial Baroreflexes by Drugs 12.1 β-Adrenergic Antagonists 12.2 Cardiac Glycosides 12.3 Antihypertensive Drugs

Change of seizure frequency in pregnant epileptic women.

Abstract: The effect of pregnancy on seizure frequency was monitored prospectively in 136 pregnancies of 122 epileptic women. Pregnancy did not influence the seizure frequency in 68 pregnancies (50%). In 50 pregnancies (37%) the number of seizures increased during pregnancy or puerperium. The seizure frequency decreased in 18 pregnancies (13%). In 34 out of 50 pregnancies (68%) the increase was associated with non-compliance with the drug regimen or sleep deprivation. In seven out of 18 pregnancies (39%) improvement was related to correction of non-compliance or sleep deprivation during the pregestational nine months. Insufficiently low plasma concentrations of antiepileptic drugs were found in 47% of the women with uncontrolled epilepsy during pregnancy. The course of epilepsy during pregnancy is primarily influenced by non-compliance, sleep deprivation during pregnancy, and inadequate therapy before and during pregnancy. With good medical attention pregnancy itself seems to have only a minimal influence on the course of epilepsy.

Cardiopulmonary Baroreflexes in Humans

Abstract: The sections in this article are: 1 Techniques 1.1 Lower-Body Negative Pressure 1.2 Congesting Cuffs and Hemorrhage 1.3 Elevation of Legs and Lower-Body Positive Pressure 1.4 Head-Out Water Immersion 1.5 Upright Tilting and Respiratory Maneuvers 2 Cardiopulmonary Baroreceptor Control of Forearm Vascular Resistance and Sympathetic Nerve Activity 3 Cardiopulmonary Baroreceptor Control of Splanchnic Circulation 4 Cardiopulmonary Baroreceptor Control of Venous Tone 5 Cardiopulmonary Baroreceptor Control of Heart Rate 6 Cardiopulmonary Baroreceptor Control of Renin and Vasopressin 6.1 Renin Release 6.2 Vasopressin Secretion 7 Interaction of Cardiopulmonary, Carotid, and Somatic Reflexes 8 Myocardial Ischemia and Infarction 8.1 Mechanisms of Bradycardia and Hypotension With Inferoposterior Infarction 8.2 Mechanisms of Tachycardia and Hypertension With Anterior Myocardial Infarction 9 Pathological States 9.1 Bradycardia and Hypotension During Coronary Arteriography 9.2 Chronic Heart Failure 9.3 Hypertension 9.4 Syncope

Evaluation of Selected Hypolipidemic Agents for the Induction of Peroxisomal Enzymes and Peroxisome Proliferation in the Rat Liver

Abstract: There is a considerable interest in developing potent and safe hypolipidemic drugs for the prevention and management of coronary heart disease in man. In rodents, many of these hypolipidemic compounds induce hepatomegaly, proliferation of peroxisomes and a polypeptide with an approximate mol. wt. of 80000 in liver cells. In the present study, we have examined 10 hypolipidemic compounds for the induction of peroxisome proliferation associated 80000 mol. wt. polypeptide (polypeptide PPA-80), peroxisomal enzymes and peroxisome proliferation in rat liver, in view of the emerging evidence that hepatic peroxisome proliferators as a class are carcinogenic in rats and mice. All ten compounds, fenofibrate (isopropyl-[4-(p-chlorobenzoyl)2-phenoxy-2-methyl] propionate; LS 2265 (taurine derivative of fenofibrate); bezafibrate (2-(4-(2-[4-chlorobenzamido)ethyl] phenoxy)-methyl propionic acid; gemfibrozil (5-2[2,5-dimethylphenoxy]2-2-dimethylpentanoic acid); methyl clofenapate (methyl-2-[4-(p-chlorophenyl)phenoxy]-2-methyl propionate); DG 5685 (5-[4-phenoxybenzyl]trans-2-(3-pyridyl)1,3-dioxane); DH 6463 (5-[4-phenoxybenzyl] trans-2-(3-pyrimidinyl)-1,3-dioxane); tiadenol(bis[hydroxyethylthio]-7, 10-decane); ciprofibrate (2,-[4-(2,2-dichlorocyclopropyl)-phenoxy]2-methyl propionic acid) and RMI-14,514 ( [5-tetradecycloxy]-2-furancarboxylic acid), produced a marked but variable increase in the activities of peroxisomal enzymes catalase, carnitine acetyltransferase, heat-labile enoyl-CoA hydratase and the fatty acid beta-oxidation system and in the amount of polypeptide PPA-80 as demonstrated by SDS-polyacrylamide gel electrophoresis. The peptide map patterns of polypeptide PPA-80 in liver induced by these compounds were strikingly similar. The ultrastructural studies demonstrate that fenofibrate, ciprofibrate, LS 2265, DG 5685 and DH 6463 can induce proliferation of peroxisomes in liver cells of rats, and further confirm the previous reports of hepatic peroxisome proliferative activity of methyl clofenapate, tiadenol, bezafibrate, gemfibrozil and RMI-14514, as shown morphologically. Whether these structurally unrelated chemicals or their metabolite(s) directly activate the peroxisome specific genes to induce this multi-enzyme system or they exert their action on peroxisomes indirectly by causing fatty acid overload in hepatocytes remains to be elucidated. These chemicals offer a simple and reproducible means of stimulating peroxisomal enzymes in liver and should serve as useful tools, for evaluating the implications of hepatic peroxisome proliferation and in elucidating the mechanism of peroxisome proliferator-induced carcinogenesis.

The fibre-type composition of the first branchial arch muscles in Carnivora and primates

Abstract: A combination of standard histochemical techniques and immunohistochemical staining using myosin type-specific antisera was used to determine the fibre-type composition of the muscles of first branchial arch origin (that is, masseter, temporalis, pterygoideus medialis and lateralis, tensor veli palatini, tensor tympani, anterior digastricus and mylohyoideus) in a wide range of the Carnivora and the Primates.

Acute tears of the posterior cruciate ligament: Clinical study and results of operative treatment in 27 cases

Abstract: Twenty-seven knees (in 27 patients) operated on for acute posterior cruciate ligament tears at the Istituto Ortopedico "G. Pini" of Milan from 1974 to 1979 are documented according to injury, type and degree of instability, surgical technique, and treatment.Materials for this study came from clinical evaluations, roentgenograms, and operative observations. Inability to obtain follow-up data eliminated two cases from the results. Followup on the other patients ranged from 2 to 5 years and consisted in part of individual interviews conducted after reintroduction into working and sport ing activity. Three separate gradings of the results were assessed: objective, subjective, and functional. The overall results in the objective category were 48% good, 44% fair, and 8% poor. Functional gradings were 55% good and 45% fair, while subjectively patients reported 70% good and 30% fair results.

The 11q;22q translocation: A collaborative study of 20 new cases and analysis of 110 families

Abstract: Following a previous collaborative study (Fraccaro et al. 1980), 20 new cases of 11q;22q translocation are described. Twelve families were ascertained through an unbalanced carrier of the translocation and eight cases were ascertained as balanced carriers. A segregation analysis was performed on the 110 families so far published. It was concluded that the 11q;22q translocation is a relatively frequent event, and that all the cases thus far reported might have the same breakpoints at 11q23.3 and 22q11.2. The translocation seems to be independent of environmental factors and it seems to have a low rate of mutation as indicated by the scarcity of de novo cases. The new data confirmed that only one type of unbalanced karyotype (47,XX or XY+der(22)t(11;22)(q23.3;q11.2)) is found among the offspring of the translocation carriers. The minimal overall recurrence risk for an unbalanced translocation was estimated to 2%. There was no difference between the recurrence risks for male and female balanced carriers, while the trend was confirmed of an excess of female balanced carriers among the phenotypically normal offspring of the t(11;22) female carriers.

Immunochemical Analysis of the Determinant Recognized by a Monoclonal Antibody (MBr1) Which Specifically Binds to Human Mammary Epithelial Cells

Abstract: A monoclonal antibody (MBr1) raised against a membrane preparation (CM) of a human breast cancer line (MCF-7) and characterized as mammary gland epithelium associated (S. Menard, E. Tagliabue, S. Canevari, G. Fossati, and M. I. Colnaghi. Generation of monoclonal antibodies reacting with normal and cancer cells of human breast. Cancer Res., 43:1295-1300, 1983), was used to biochemically define and partially purify its target antigen. The antigenic activity recognized by MBr1 was unaffected by treatment of MCF-7 cells with trypsin, protease K, or Vibrio cholerae neuraminidase and by heating at 100 degrees but was abolished by treatment with methanol. Since this behavior suggested a glycolipid nature of the MBr1-defined antigen, total lipids were obtained by chloroform:methanol or tetrahydrofuran:phosphate buffer extractions from crude membrane preparations of MCF-7 cells and of breast cancer surgical specimens. Total absorption of MBr1 activity was found by breast cancer lipid extracts, whereas no absorbing capability was detected with a series of highly purified acid and neutral glycolipids or with normal and neuraminidase-treated red blood cells of human, ox, and sheep species. The same pattern of inhibition of MBr1-binding activity was obtained with total lipid extract and both phases after diethyl ether partition. However, when the three extracts were chromatographed on diethylaminoethyl-Sepharose, the antigenic activity was recovered only in the neutral glycolipid fractions. Periodate oxidation of MCF-7 crude membrane preparation abolished MBr1-binding activity, suggesting that the carbohydrate portion of the molecule may constitute the antigenic determinant.

Secondary and essential cryoglobulinemias. Frequency, nosological classification, and long-term follow-up.

Abstract: The clinical and immunochemical classification of 166 patients with cryo-globulinemia are presented. 52% of the cryoglobulins were detected in patients hospitalized because of various causes. The most

Successful treatment of hyperthyroidism due to nonneoplastic pituitary TSH hypersecretion with 3,5,3'-triiodothyroacetic acid (TRIAC).

Abstract: The effects of 3,5,3′-triiodothyroacetic acid (TRIAC) or bromocriptine oral administration on serum TSH and thyroid hormone concentrations were studied in a 47 yr old woman affected with hyperthyroidism due to nonneoplastic pituitary hypersecretion of TSH. The diagnosis was made on the basis of elevated thyroid hormone levels (total T4 and T3:170–198 and 2.9–3.5 nmol/l;free T4 and T3:20.7–25.5 and 12.5–14.5 pmol/l, respectively) and inappropriately high serum TSH (9.7–15.6 μU/ml) in the absence of radiological evidence of pituitary tumor. Typical alterations of several parameters of peripheral thyroid hormone action [BMR: + 25%, pulse wave arrival time: 130 msec, pre-ejection period/left ventricular ejection time (PEP/LVET): 0.26] were indicative of hyperthyroidism. Abnormal thyroid stimulators, as well as substances known to interfere in RIA determination were absent. TSH secretion was suppressed by T3 (-90%), dopamine (-52%), bromocriptine (-44%), somatostatin (-45%) and dexamethasone (-36%) administration, and stimulated by TRH (+ 438%), domperidone (+ 123%) and methimazole (+426%). As these findings were suggestive of intact regulatory mechanisms for TSH secretion operating at a higher set point, therapeutical trials with either TRIAC or bromocriptine were carried out owing to the ability of these compounds to suppress TSH secretion. No significant variations in serum TSH, total and free thyroid hormone concentrations were observed after 2 months of bromocriptine treatment (10 mg/day). On the contrary, during TRIAC administration (3 mg/day for 3 weeks) serum TSH, total and free thyroid hormone concentrations fell to within the euthyroid range (TSH: 4.8 μU/ml; total T4 and T3:142 and 2.5 nmol/l; free T4 and T3:14.2 and 7.8 pmol/l, respectively) and all the parameters of peripheral thyroid hormone action reverted to normal (BMR: + 5%, pulse wave arrival time: 198 msec, PEP/LVET: 0.34), without any appreciable untoward effect. Lower TRIAC dose (1 mg/day was ineffective and its withdrawal was followed by a rapid elevation of serum TSH and thyroid hormone levels and reappearance of hyperthyroidism. Long term treatment with 2.1 mg/day caused the remission of clinical hyperthyroidism, though serum TSH levels still remained little above the normal range (5.2–7.1 μU/ml). It is concluded that the nonneoplastic pituitary TSH hypersecretion can be successfully treated with TRIAC.

Recurrent ischemic attacks in two young adults with lupus anticoagulant.

Abstract: Two young adults with lupus anticoagulant had multiple attacks of cerebrovascular ischemia in different arterial territories. Cerebral angiography was normal. One patient had a new episode during anticoagulant therapy, but has remained asymptomatic on antiplatelet treatment. In the other, further events occurred during treatment with platelet-inhibiting drugs, but there have been no recurrences with adequate anticoagulant therapy. Lupus anticoagulants are possible causes of otherwise unexplained thromboembolic events. Due to the variable mode of action of these immunoglobulins, platelet-inhibiting drugs may in some cases be considered as a prophylactic alternative to anticoagulant treatment.

Repetitive passive Q-switching and bistability in lasers with saturable absorbers

Abstract: We report detailed experimental data on the passive Q-switching operation in a CO2 laser with CH3I saturable absorber, and on the transient behaviour in the near-Q-switching situation. Under suitable operating conditions, we found bistability in the output power. In some cases, we observed the simultaneous presence of bistability and passive Q-switching. The theoretical part of the paper starts from the four-level model of laser with saturable absorber, as formulated by other authors. By adiabatically eliminating the variables of the resonant levels, we reduce the problem to a set of three differential equations, from which we derive explicit analytical conditions for the rise of passive Q-switching. These conditions turn out to be in good qualitative and partially quantitative agreement with our experimental findings as well as with other experimental data previously obtained by other authors. Finally we classify the possible combinations of passive Q-switching and bistability that one can find in this type of experiments.