Biomedical subjects

A Bertolini

Publications and source records attributed to A Bertolini.

At least 73 records · Page 4Linked to original sources

PubMed1997

Physostigmine has a life-saving effect in rats subjected to prolonged respiratory arrest.

We have previously reported that centrally-acting cholinomimetic drugs have a prompt and sustained resuscitating effect in pre-terminal conditions of hemorrhagic shock in rats. Here we have studied the effect of physostigmine in another experimental condition of hypoxia in anesthetized rats, which were endotracheally intubated and subjected to prolonged (5 min) interruption of ventilation. This led to a dramatic fall in mean arterial pressure (MAP), pulse pressure (PP), heart rate (HR), pH, PO2, SO2 and base excess, while PCO2 increased; the electroencephalogram (EEG) became isoelectric, and the electrocardiogram (ECG) showed marked bradycardia, P-wave inversion, partial atrio-ventricular block and S-T segment elevation; all saline-treated rats died of cardiac arrest within 7.01 +/- 0.85 min of ventilation being resumed. When ventilation resumption was associated with the simultaneous intravenous (i.v.) injection of physostigmine (70 microg/kg) there was an almost immediate and impressive increase in MAP, PP and HR, with normalization of ECG within 4 min and full recovery of EEG after 30-50 min. This was associated with a normalization of blood gases and pH. Fifteen days later 40% of treated animals were still alive and apparently in normal health, the mean survival time of the remaining 60% animals being 22.67 +/- 10.19 h. Pretreatment with atropine sulfate or hemicholinium-3 did not modify the response to physostigmine, which, however, was strongly antagonized by the intracerebroventricular injection of mecamylamine. These results suggest that centrally-acting cholinomimetic agents may have a resuscitating effect in pre-terminal conditions produced by prolonged asphyxia, probably through the direct activation of nicotinic receptors in the central nervous system.

Animals↗

PubMed1997

Galantide improves social memory in rats.

The role of galanin in memory paradigms has been largely evaluated. The galanin-antagonist galantide, a chimeric peptide obtained from amino acids 1-13 of galanin attached to the C-terminal fragment of bradykinin, has been found to improve social memory in 'social recognition' test when i.c.v. administered at doses varying from 6-6000 nmoles.

Animals↗

PubMed1997

Hepatitis C virus infection and related liver disease in children of mothers with antibodies to the virus.

OBJECTIVE: To evaluate the clinical, biochemical, and virologic features associated with hepatitis C virus (HCV) infection acquired early in life from mothers with antibodies to HCV (anti-HCV). STUDY DESIGN: Multicenter prospective-retrospective study in Italian children. PATIENTS: Two groups of children were investigated. Group 1 included 14 infants, born to mothers with anti-HCV but without human immunodeficiency virus infection, who became seropositive for HCV RNA during the first year of life and were thus considered infected. Group 2 included 16 children with chronic hepatitis C, aged 1 1/2 to 14 years, whose mothers were the unique potential source of infection. Both groups were followed for 12 to 48 months. METHODS: Alanine transaminase (ALT), anti-HCV, and HCV RNA were investigated by the polymerase chain reaction on entry to the study and during follow-up. RESULTS: All children in group 1 had anti-HCV throughout follow-up, and all had ALT abnormalities, ranging from 1.5 to 10.5 times the normal value during the first 12 months. During further follow-up, 5 of 10 children had HCV RNA with abnormal ALT values, 3 had a return to normal of the ALT values but continued to have viremia, and 2 eventually had normal ALT values and clearance of HCV RNA. Of the 16 children in group 2, all were free of symptoms and 62% had only slight ALT elevations; 7 who underwent liver biopsy had histologic features of minimal or moderate hepatitis. CONCLUSIONS: HCV infection acquired early in life from mothers with anti-HCV is usually associated with biochemical features of liver damage during the first 12 months of life. Progression to chronicity seems to occur in the majority of cases, although HCV-associated liver disease is likely to be mild throughout infancy and childhood.

Alanine Transaminase↗

PubMed1997

Effect of potassium channel modulators on male sexual behavior.

In the adult sexually experienced male rat, the intracerebroventricular (i.c.v.) injection of pinacidil, a KATP channel opener, at the dose of 100-150-300 micrograms/rat worsened the copulatory performance in the presence of a receptive female, whereas the administration of glibenclamide, a KATP channel blocker, at the dose of 0.5 and 3 mg/kg intraperitoneally (i.p.) had an improving effect. These data indicate that KATP channels in target neurons may play an important role in the physiology of male sexual behavior.

Animals↗

PubMed1997

Streptozotocin-induced diabetes provokes changes in serotonin concentration and on 5-HT1A and 5-HT2 receptors in the rat brain.

Since reduced levels of brain serotonin are known to cause behavioural abnormalities, to which diabetics are also prone, we investigated the effect, in rats, of chronic diabetes on brain serotonin concentration and on the numbers of 5-HT(1A) and 5-HT2 receptors in cerebral cortex and brainstem. Our data show that streptozotocin induces a longlasting hyperglicemia that is associated with a decrease in cerebral concentration of serotonin and with an accompanying increase in the maximum number of 5-HT(1A) and 5-HT2 receptors in the brain areas studied. Our results may suggest that changes in serotonergic transmission in the CNS play a role in diabetes-related behavioural abnormalities.

Animals↗

PubMed1997

Inhibition of nitric oxide synthases enhances the effect of ACTH in hemorrhagic shock.

In a model of volume-controlled hemorrhagic shock in rats, invariably leading to death within 30 min of bleeding termination, the intravenous (i.v.) bolus injection of ACTH-(1-24) at the dose of 0.16 mg/kg restored cardiovascular and respiratory functions and greatly prolonged survival. I.v. or intracerebroventricular (i.c.v.) treatment with NG-nitro-L-arginine methylester (L-NAME), a non-isoform-selective inhibitor of nitric oxide synthases (NOSs), at the doses of 2.5-10 mg/kg i.v. or 0.015-0.135 mg/kg i.c.v., as well as i.v. treatment with S-methylisothiourea (SMT), a selective inhibitor of the inducible isoform of NOS, at the doses of 0.001-3 mg/kg, dose-dependently improved cardiovascular and respiratory functions and potentiated the effect of a subthreshold dose (0.02 mg/kg) of ACTH-(1-24). On the other hand, either intraperitoneal or i.c.v. pretreatment with L-arginine, the substrate of NOSs, prevented the effect of ACTH-(1-24). These data suggest that inhibition of NO overproduction is involved in the mechanism of action of ACTH-(1-24) in shock reversal.

Animals↗

PubMed1997

Relationship between left ventricular diastolic function and atrial natriuretic factor in never-treated mild hypertensives.

Using digitized M-mode echocardiograms, we evaluated the relationship between plasma atrial natriuretic factor (ANF) and morphofunctional characteristics of the left ventricle (LV) in 24 mild hypertensive men, never treated, with normal renal function. For each subject we collected a blood sample for plasma ANF evaluation and, immediately after, we recorded the LV echocardiogram. All the patients had normal LV diastolic diameter and systolic function; LV hypertrophy was present in 10 patients, 7 of whom had left atrial enlargement, and 13 patients had impaired LV diastolic function. ANF was similar between patients with and without LV hypertrophy, as well as between patients with and without left atrial enlargement, whereas ANF was significantly (P < .01) higher in patients with LV diastolic dysfunction than in patients with normal diastolic function. ANF was inversely correlated with both indices of diastolic function (peak lengthening rate and peak wall thinning rate), whereas it did not correlate with blood pressure, heart rate, end-systolic wall stress, and other LV parameters. In conclusion, from our results, ANF level in never-treated mild hypertensives is related neither to the degree of LV hypertrophy nor to the afterload, expressed as blood pressure or end-systolic wall stress, whereas it is mainly influenced by LV diastolic function: the diastolic impairment induces an increase in ANF level, probably through an increased atrial stretch.

Adult↗

PubMed1997

Bidirectional cavo-pulmonary anastomosis with an additional flow source to the lungs: clinical experience in 21 cases.

The Fontan operation is considered a palliative procedure for the treatment of complex congenital heart diseases with a morbidity and mortality that are not negligible, especially in high-risk patients. In these cases, a bidirectional cavopulmonary anastomosis with additional source of blood flow to the lungs can represent a valuable surgical option. Between November 1992 and December 1995, 21 patients with univentricular heart physiology were submitted to bidirectional cavopulmonary anastomosis with additional blood flow the additional flow consisted of an aortopulmonary shunt in 13 cases, pulmonary artery banding in seven cases, and pulmonary artery stenosis in one case. Mean age at operation was 35.5 months (range 4 months to 12 years) and mean body weight 10.9 (range 4-24.4) kg. Hospital mortality was zero. Morbidity (pleuropericardial effusions) was significant in one case. There were three late deaths (14%) caused by worsening atrioventricular valve regurgitation: two of these occurred in patients with right isomerism. Late haemodynamic evaluation documented a significant increase in cardiac output (P < 0.01) and oxygen saturation (P < 0.05) during pharmacological stress testing. Angiographic characterization of blood flow distribution to the lungs showed better results when the additional blood flow was represented by an anterograde source (pulmonary artery banding or native pulmonary artery stenosis). In conclusion, bidrectional cavopulmonary anastomosis with additional blood flow is a good alternative to classic or fenestrated Fontan technique in high-risk patients. Secondly, the diagnosis of isomerism could be a contraindication to this type of surgery, because the persistent volume overload could worsen atrioventricular valve regurgitation. Thirdly, the pharmacological stress testing shows a favourable behaviour of cardiac output and arterial oxygen saturation. Fourth, the type of additional blood flow seems to condition both pulsatility and distribution of pulmonary blood flow.

Child↗

PubMed1997

Noninvasive evaluation of cardiotoxicity of 5-fluorouracil and low doses of folinic acid: a one-year follow-up study.

PURPOSE: To conduct a serial evaluation of the cardiac effects of antineoplastic therapy with 5-fluorouracil (5-FU) and low-dose folinic acid. PATIENTS AND METHODS: Sixteen patients with colon-rectal carcinoma, without cardiac disease, treated with 400 mg/ m2/die of 5-FU and 20 mg/m2/die of folinic acid for five days, once a month, for six months. Parameters evaluated: blood pressure, ECG, two-dimensional and digitized M-mode echocardiograms before and after the first and fifth drug administrations of the first cycle, after the fifth drug administration of the sixth cycle and six months after the treatment. RESULTS: Blood pressure, heart rate, left ventricular (LV) diameter and LV mass index did not change; all of the patients showed a decrease in the peak shortening rate of the LV diameter index of systolic function, and of the peak lengthening rate of the LV diameter and peak thinning rate of LV posterior wall, indexes of diastolic function, with abnormal values in 11 patients at the end of treatment LV wall motion remained normal in all; two patients developed transient T wave inversion without chest pain and with normal cardiac enzymes and myocardial scintigraphy during dypiridamole stress test. Six months after the treatment all indexes of LV systolic and diastolic function had returned within the normal limits and were similar to pre-treatment values. CONCLUSIONS: 5-FU and low-dose folinic acid treatment induced a decrease of LV systolic function and an impairment of diastolic function, that developed without symptoms and were transient and reversible.

Adult↗

PubMed1997

Resuscitating effect of melanocortin peptides after prolonged respiratory arrest.

1. The resuscitating activity of melanocortin peptides (MSH-ACTH peptides) was tested in an experimental model of prolonged respiratory arrest. 2. Anaesthetized, endotracheally intubated rats subjected to a 5 min period of ventilation interruption, invariably died from cardiac arrest within 6-9 min of resumption of ventilation. 3. When resumption of ventilation was associated with the simultaneous intravenous (i.v.) injection of a melanocortin peptide (alpha-MSH or ACTH-(1-24)) (160 microg kg(-1) there was an almost immediate (within 1 min), impressive increase in cardiac output, heart rate, mean arterial pressure (+ 560% of the before-treatment value) and pulse pressure (+356% of the before-treatment value), with full recovery of electroencephalogram after 30-45 min. Blood gases and pH were normalized within 15-60 min after treatment, and all treated animals eventually recovered completely and survived indefinitely (= more than 15 days). 4. The same response was observed in adrenalectomized animals, as well as in animals pretreated with a beta1-adrenoceptor blocking agent (atenolol, 3 mg kg(-1), i.v.), or with an alpha1-adrenoceptor blocking agent (prazosin, 0.1 mg kg(-1), i.v.), or with an adrenergic neurone blocking agent (guanethidine, 10 mg kg(-1), intraperitoneally). 5. An effect quite similar to that produced by melanocortins was obtained with ouabain (0.1 mg kg(-1), i.v.); the antioxidant drug, glutathione (75 mg kg(-1), i.v.) also produced 100% resuscitation, but the effect was slower in onset. On the other hand, adrenaline (0.005 mg kg(-1), i.v.) was able to resuscitate only 1 out of 8 rats and dobutamine (0.02 mg kg(-1), i.v.) resuscitated 4 out of 8 rats; moreover, the effect of both catecholamines was much slower in onset than that of melanocortins and the initial, impressive stimulation of cardiovascular function was absent. 6. These results show that melanocortin peptides have a resuscitating effect in a pre-terminal condition produced in rats by prolonged asphyxia. This effect seems primarily due to the restoration of cardiac function, not mediated by catecholamines. These data also suggest that these peptides may have potential therapeutic value in conditions of transient cardiac hypoxia and re-oxygenation such as occur in coronary artery disease.

Adrenocorticotropic Hormone↗

PubMed1997

Atrial natriuretic peptide and 24 h blood pressure.

BACKGROUND: Atrial natriuretic peptide (ANP) is a hormone involved in the cardiovascular modulation of blood pressure and volume homeostasis. OBJECTIVE: To compare ANP levels in normotensives and hypertensives and to correlate ANP levels with ambulatory blood pressure parameters. METHODS: Plasma samples for ANP determination (using a double-antibody radioimmunoassay Kit) were obtained from 33 consecutive subjects (24 hypertensives, nine normotensives) who had rested supine for 30 min. Afterwards, all of the subjects were subjected to 24 h non-invasive blood pressure monitoring. We found no significant difference between the two groups with regard to ANP levels (95.1+/-29 versus 96.9+/-33 pg/ml, in normotensives and hypertensives, respectively). Also, when hypertensive patients were divided according to their family history of hypertension, ANP levels were similar. There was no correlation between the ANP level and the pre-sampling blood pressure or between the ANP level and the following ambulatory blood pressure monitoring parameters: 24 h, diurnal and nocturnal systolic and diastolic blood pressures, systolic and diastolic loads, nocturnal blood pressure reduction and blood pressure variation coefficients. CONCLUSION: Both the pre-sampling blood pressure and ambulatory monitoring results (sustained blood pressures and pressure variations during the 24 h period) do not seem to influence basal ANP levels in patients with hypertension. These data do not account for a role of this peptide in cardiovascular control, in hypertension.

Journal Article↗

PubMed1997

[Differential types of pulmonary flow in bidirectional cavo-pulmonary anastomosis with an additional flow source].

While Fontan operation is considered a palliative procedure for the treatment of complex congenital heart disease, its morbidity and mortality are certainly not negligible, especially in high-risk patients. In our opinion, a bidirectional cavo-pulmonary anastomosis with an additional source of blood flow to the lungs (Blalock-Taussig shunt, pulmonary artery banding, native pulmonary stenosis) represents a valuable surgical option in this subset of patients. From November 1992 to September 1994, sixteen patients with complex congenital heart disease underwent bidirectional cavo-pulmonary anastomosis, leaving an additional source of blood flow in place (modified Blalock-Taussig shunt in 9 cases, pulmonary artery banding in 6 cases, native pulmonary stenosis in 1 case). Eight of these patients (50%) were reinvestigated after a mean follow-up of 15.7 months (range 1-26 m). It has been possible to differentiate two types of pulmonary blood flow, according to the nature of the additional flow source; in the case of cavo-pulmonary anastomosis and pulmonary artery banding or pulmonary stenosis, pulmonary blood flow was pulsatile and evenly distributed to both lungs, while in the case of bidirectional cavo-pulmonary anastomosis and Blalock-Taussig shunt, pulmonary flow was non pulsatile and asymmetric (angiographic criteria). There were no hospital deaths. Late mortality was 12.5% (2 pts) due to worsening of atrioventricular valve regurgitation. In one of these two patients, prolonged pleural and pericardial effusion occurred. In conclusion, bidirectional cavo-pulmonary anastomosis with an additional flow source is a good alternative to classic or fenestrated Fontan operation in the treatment of complex congenital heart disease. The best results are obtained with an additional flow source represented by pulmonary artery banding or pulmonary stenosis, due to pulsatility and uniform distribution of blood flow in the pulmonary district. Morbility and mortality compare favorably with the rates observed in classic or fenestrated Fontan operation.

Anastomosis, Surgical↗

PubMed1997

[Classification of congenital heart diseases and surgical interventions in pediatric cardiology for the standardization of hospitalization records].

The utilization of DRGs for the evaluation of hospital activity requires the availability, on a current basis, of coded in-patient records (Hospital Discharge Form, SDO) with information concerning nosology of the patient and procedures performed. Consequently, the promotion of a standardized use of ICD.9 and ICD.9.CM code systems (International Classification of Diseases, 9th Revision, and International Classification of Diseases, 9th Revision, Clinical Modification) among clinicians is necessary. The National Research Council, Council Research Hospital for Cardiology and Cardiac Surgery (CREAS-IFC-CNR) has promoted the establishment of a permanent work group for the evaluation of the activity in the field of pediatric cardiology and cardiosurgery at a national level. In co-operation with two leading institution (AO "Bambino Gesù", Rome; AO "G. Gaslini", Genoa) an in-patient survey has been promoted including an overall revision of the ICD.9.CM code systems both for diagnosis and procedures in order to improve the standardization of data. Besides, the fitness of DRGs allocation by different codes has been judged. Some general and specific suggestions upon codes adequacy and DRGs identification have emerged from this study. The aim of this paper is to spread this preliminary standardization activity of the group as a contribution to the improvement of in-patient coded records quality.

Age Factors↗

PubMed1997

Ambulatory blood pressure, nocturnal blood pressure reduction and plasma catecholamines.

OBJECTIVE AND DESIGN: Controversial data have been reported on plasma catecholamines in hypertensives. Aims of this study were to find whether 24-hour ambulatory blood pressure was correlated with circulating catecholamines and to investigate whether nocturnal blood pressure reduction was associated with baseline plasma catecholamines. Samples for catecholamine determination were obtained in 34 consecutive male subjects after a 30-minute rest and before ambulatory blood pressure monitoring. RESULTS: Hypertensive patients (n = 22; 24-hour blood pressure: 145 +/- 14/94 +/- 6 mm Hg) showed similar norepinephrine and epinephrine levels when compared with normotensives (n = 12; 24-hour blood pressure: 124 +/- 6/81 +/- 6 mm Hg), and higher dopamine values (hypertensives: 64.6 +/- 58; normotensives: 26.2 +/- 31 pg/ml; p < 0.05). A positive correlation was observed between dopamine and diastolic nocturnal blood pressure (p < 0.05) while a negative correlation was found between dopamine and nocturnal diastolic blood pressure reduction (p < 0.025). No significant relationship was observed between both norepinephrine and epinephrine, and 24-hour blood pressures. CONCLUSIONS: Since previous reports have documented malfunctioning of dopaminergic system in hypertension, the higher levels of circulating plasma dopamine found in hypertensive patients in the present study may account for a peripheral compensatory increase. The correlation between dopamine and nocturnal blood pressure fall seems to indicate that the impairment of dopaminergic system may influence the 24-hour blood pressure profile, affecting the nocturnal blood pressure reduction.

Adult↗

PubMed1996

Endogenous beta-endorphins in hypertension: correlation with 24-hour ambulatory blood pressure.

OBJECTIVES: The aims of this study were to determine whether hypertensive patients showed increased endogenous opioid tone and to find a possible correlation between beta-endorphin levels and 24-h ambulatory blood pressure. We also investigated whether circulating beta-endorphin levels were associated with pain perception at rest. BACKGROUND: Experimental studies suggest an involvement of the endogenous opioid system in cardiovascular control mechanisms. METHODS: We determined baseline beta-endorphin plasma levels by radioimmunoassay in 81 consecutive subjects (48 hypertensive, 33 normotensive) after a 30-min rest and before 24-h ambulatory blood pressure monitoring. In 72 of 81 subjects with a dental formula suitable for the pulpar test (graded increase of test current -0 to 0.03 mA applied to three healthy teeth), pain perception was also investigated. RESULTS: Hypertensive patients showed higher beta-endorphin plasma levels than normotensive subjects (p < 0.002). Circulating endogenous opioid levels correlated with 24-h diastolic blood pressure (p < 0.01), whereas the relation with systolic pressure did not reach statistical significance. When 24-h blood pressure recordings were divided into daytime and nighttime values, and blood pressure loads (percent of measurements > or = 140 mm Hg for systolic blood pressure and > or = 90 mm Hg for diastolic pressure) were calculated, a significant correlation was found between beta-endorphin levels and diastolic pressures and load. Similarly, presampling diastolic blood pressure was significantly correlated with beta-endorphin levels. Of the 72 subjects tested, hypertensive patients showed a lower pain sensitivity than normotensive subjects. A positive correlation was found between pain threshold and circulating beta-endorphin levels (p < 0.05). CONCLUSIONS: Sustained arterial pressure is probably involved in the tonic activation of cardiovascular mechanisms linked to endogenous opioid tone. Circulating plasma endorphins may account, at least in part, for the pain perception pattern relating to blood pressure levels at rest.

Adult↗

PubMed1996

Blockade of the polyamine site of NMDA receptors produces antinociception and enhances the effect of morphine, in mice.

The possible effect of ifenprodil--a potent antagonist at the polyamine site of the NMDA receptor complex--on nociceptive threshold and morphine analgesia was investigated in mice. In the hot plate test, the intraperitoneal (i.p.) injection of ifenprodil significantly prolonged the reaction time of mice at the dose of 30 mg/kg, and increased the analgesic effect of morphine. In the phenylquinone writhing test, ifenprodil reduced the number of abdominal constrictions of mice starting from the dose of 2.5 mg/kg i.p., and increased the effect of morphine. The effect of ifenprodil on pain threshold was prevented by naloxone. Moreover, ifenprodil antagonized the pain threshold-reducing effect of alpha-melanocyte-stimulating hormone (0.05 microgram/mouse, intracerebroventricularly). These data show that blockade of the polyamine site of the NMDA receptor complex produces analgesia and increases the analgesic effect of morphine.

Analgesia↗

PubMed1996

Effect of acute and chronic treatment with triiodothyronine on serotonin levels and serotonergic receptor subtypes in the rat brain.

Hyperthyroidism is often associated with behavioral disorders, and thyroid hormones modify receptor sensitivity as well as the synthesis and/or turnover rate of many neurotransmitters. We evaluated the influence in adult rats of triiodothyronine (T3), administered s.c. (100 micrograms/kg) acutely (once only) or chronically (once a day for 3 or 7 consecutive days), on brain serotonin concentration and on the density and affinity of two brain serotonin (5-HT) receptor subtypes mainly involved in behavioral effects. After both acute and chronic T3 treatment, serotonin levels increased in the cerebral cortex but not in the hippocampus. The density and affinity of 5-HT1A receptors (using [3H]-8-OH-DPAT as ligand) were not affected, while there was a significant decrease in the number of 5-HT2 receptors in the cerebral cortex (using [3H]ketanserin as ligand). This observation might indicate that thyroid hormones enhance 5-HT concentration in certain brain areas, thus causing a down-regulation of 5-HT2 receptors. The serotonergic system could be involved in the complex brain-neurotransmitter imbalance underlying hyperthyroidism-linked behavioral changes.

Animals↗

PubMed1996

The reversal of experimental hemorrhagic shock induced by nicotine and dimethylphenylpiperazinium is adrenal-dependent.

In a rat model of volume-controlled hemorrhagic shock causing the death of all control animals within 30 min, the intravenous injection of either nicotine (50 micrograms/kg) or dimethylphenylpiperazinium (DMPP) (0.5 micrograms/kg) produced a rapid and sustained reversal of the shock condition, with 100% survival 2 h after treatment. Bilateral adrenalectomy completely prevented the anti-shock effect of the two drugs, even though administered at higher doses (150 micrograms/kg in the case of nicotine; 10 micrograms/kg in the case of DMPP). It is concluded that stimulation of adrenaline release plays a fundamental role in the mechanism of action of nicotine- and DMPP-induced shock reversal.

Adrenal Glands↗