Search PubMed⌕ Search

Biomedical subjects

G Rossi

Publications and source records attributed to G Rossi.

At least 415 records · Page 23Linked to original sources
PubMed1994

Influence of thyroid status on the paradoxical growth hormone response to thyrotropin-releasing hormone in human obesity.

Thyrotropin-releasing hormone (TRH) tests were performed in 38 age- and weight-matched obese but otherwise healthy men. In all subjects, total thyroxine (T4) and triiodothyronine (T3) concentrations were in the normal range. According to basal and TRH-stimulated serum thyrotropin (TSH) levels, subjects were divided into the following three groups: group I (n = 14), euthyroid subjects; group II (n = 11), euthyroid subjects with normal basal but abnormally elevated TSH responses to TRH; group III (n = 13), subjects with elevated basal and TRH-induced TSH levels (subclinical hypothyroidism). Basal TSH levels were 1.8 +/- 0.4 mU/L in group I, 1.7 +/- 0.3 in group II, and 6.0 +/- 0.7 in group III. In both groups II and III, TRH-induced TSH increments were above the normal range (maximal increment > 14 mU/L) and were significantly higher than in group I. The definition of euthyroidism for groups I and II and of subclinical hypothyroidism for group III according to the basal levels of TSH was confirmed by clinical (Billewicz index), hormonal (serum free-T4 levels), and metabolic (serum apoprotein [apo] AI levels) parameters. Basal concentrations of growth hormone (GH) were similar in all groups. When GH levels after TRH stimulation were measured, significant increments (peak minus baseline > 5 micrograms/L) were observed in nine of 13 hypothyroid obese men. The overall mean peak GH increase in group III was 4.5 times higher than baseline and was observed at 45 minutes. None of the euthyroid obese subjects of groups I and II showed any significant change in GH levels in response to TRH.(ABSTRACT TRUNCATED AT 250 WORDS)

Growth Hormone↗
PubMed1994

Echo Doppler diastolic function and exercise tolerance.

OBJECTIVE: To investigate the possible association between Doppler left ventricular filling pattern and exercise capacity in a group of normotensives to severe hypertensive patients. BACKGROUND: Invasive left ventricular filling indexes evaluated at rest are reported to be related to exercise capacity in heart failure. Whether exercise capacity is limited by abnormalities of left ventricular filling also in other less severe conditions is however unclear. METHODS: Fifty-one subjects with normal to severely elevated blood pressure underwent a standard exercise test on cycle ergometer, negative for myocardial ischemia, and a complete echo Doppler evaluation showing a basal systolic function within normal limits. RESULTS: Basal systolic function indexes were not significantly related to exercise duration. On the contrary, exercise duration was highly significantly correlated to the relative atrial contribution to left ventricular filling (0.001 < P < 0.05), in both the overall group and the two subgroups in whom exercise was interrupted because of fatigue (n = 30) or because of attaining target heart rate (n = 21). Significant correlations were also observed between exercise time and resting blood pressure, whereas no association with resting heart rate, age and body surface area was found. Exercise time also correlated to left ventricular mass and mass index but not to left ventricular volume. Multiple regression analysis showed that exercise tolerance was significantly related to diastolic blood pressure and left ventricular filling. Echo Doppler indexes of left ventricular filling are associated with exercise duration; left ventricular diastole could thus influence effort tolerance, not only in patients with cardiac insufficiency, but also in subjects with normal to elevated blood pressure levels and normal systolic function at rest.

Blood Pressure↗
PubMed1994

Effect of subthreshold ouabain on the tone of guinea-pig aortic strips following repeated noradrenaline stimulation.

1. The effect of ouabain at a concentration (0.8 microM) that does not induce contractile response in guinea-pig aortic strips has been studied on endothelium-denuded strips repeatedly stimulated with 1 microM noradrenaline or 60 mM K+ applied for 5 min every 30 min. 2. The resting tone (i.e. the tone between one noradrenaline stimulation and the following) of the aortic strips exposed to ouabain increased progressively, whereas the control strips (no ouabain) completely relaxed on washout of the agonist. In the aortic strips stimulated by 60 mM K+, the resting tone did not increase. 3. The calcium antagonist, verapamil, did not affect the increase in tone, that was nevertheless strictly dependent on external calcium, since the contracted strips completely relaxed on calcium removal and promptly contracted again on calcium readdition. This finding indicates a mechanism independent of voltage-gated calcium channels. 4. Caffeine-induced contractions, taken as a measure of sarcoplasmic reticulum calcium content, were amplified by the presence of ouabain in aortic strips either stimulated by noradrenaline or unstimulated, with a larger increase in the former. 5. These results suggest that the repeated stimulation of guinea-pig aortic strips by noradrenaline in the presence of ouabain, by raising both intracellular Na+ and Ca2+, decreases the ouabain threshold concentration required for contraction, thus increasing the responsiveness of vascular smooth muscle to the glycoside.

Animals↗
PubMed1994

Pleural mesothelioma associated with non-Hodgkin's lymphoma.

Occupational exposure to asbestos has been associated with an increased incidence of lung and gastric cancers, mesotheliomas, and myelolymphoid malignancies. A new observation of a patient with indirect exposure to asbestos who developed mesothelioma and plasmacytoid lymphocytic non-Hodgkin's lymphoma is described. This report and the previously described stimulation of B lymphocytes by asbestos suggests that the association of mesothelioma with lymphoid and plasma cell malignancies is not merely a coincidence.

Asbestosis↗
PubMed1994

Gene expression, localization, and characterization of endothelin A and B receptors in the human adrenal cortex.

Compelling evidence indicates that the endothelium-derived potent vasoconstrictor endothelin-1 (ET-1) stimulates aldosterone secretion by interacting with specific receptors. Although two different ET-1 receptors have been identified and cloned, the receptor subtype involved in mediating aldosterone secretion is still unknown. Accordingly, we wished to investigate whether the genes of ET-1 and of its receptors A and B are expressed in the normal human adrenal cortex. We designed specific primers for ET-1 and the ETA and ETB receptors genes and developed a reverse transcription polymerase chain reaction (RT-PCR) with chemiluminescent quantitation of the cDNA. In addition, we carried out 125I ET-1 displacement studies with cold ET-1, ET-3 and the specific ETA and ETB ligands BQ123 and sarafotoxin 6C. Localization of each receptor subtype was also investigated by autoradiography. Binding experiments were first individually analyzed by Scatchard and Hofstee plot and then coanalyzed by the nonlinear iterative curve fitting program Ligand. Histologically normal adrenal cortex tissue, obtained from kidney cancer patients (n = 7), and an aldosterone-producing adenoma (APA), which is histogenetically derived from the zona glomerulosa (ZG) cells, were studied. Results showed that the ET-1, ETA and ETB mRNA can be detected by RT-PCR in all adrenal cortices as well as in the APA. The best fitting of the 125I ET-1 displacement binding data was consistently provided by a two-site model both in the normal adrenal cortex (F = 22.1, P < 0.0001) and in the APA (F = 18.4, P < 0.0001). In the former the density (Bmax) of the ETA and ETB subtype was 2.6 +/- 0.5 pmol/mg protein (m +/- SEM) and 1.19 +/- 0.6, respectively. The dissociation constant (Kd) of ET-1, ET-3, S6C, and BQ-123 for each receptor subtype resulted to be within the range reported for human tissue for the ETA and ETB receptors. In the APA tissue the Bmax tended to be lower (1.33 and 0.8 pmol/mg protein, for the ETA and ETB, respectively) but the Kd were similar. Autoradiographic studies confirmed the presence of both receptor subtypes on the ZG as well as on APA cells. Thus, the genes of ET-1 and both its receptor subtypes ETA and ETB are actively transcribed in the human adrenal cortex. Furthermore, both receptor subtypes are translated into proteins in ZG and APA cells.

Adrenal Cortex↗
PubMed1994

Clozapine in Huntington's chorea.

In an open-label trial, we evaluated the efficacy of clozapine on abnormal involuntary movements in five patients with Huntington's chorea. We administered clozapine at increasing doses of 25, 50, and 150 mg/d for 3 weeks. Subjective self-evaluation of all patients reported reduction of chorea and improvement of daily living activities. At the end of the trial, all patients requested to continue with clozapine. Objective evaluation with the Abnormal Involuntary Movements Scale demonstrated in all patients moderate-to-marked reduction of abnormal involuntary movements without any significant side effects; the improvement was dose-dependent and markedly decreased 1 week after drug withdrawal.

Clozapine↗
PubMed1994

Ultrasonic endarterectomy: experimental and initial clinical results in carotid stenosis.

PURPOSE: The effects of ultrasonic endarterectomy, evaluated experimentally and clinically, were compared with the results obtained with controversial endarterectomy. METHODS EXPERIMENTAL: An ultrasonic vascular dissector with a frequency of 29 kHz was used for ultrasonic endarterectomy. Gross and histologic observation was made on 22 fresh human cadaver atherosclerotic vessels, of which 16 were treated with ultrasound endarterectomy and 6 conventionally. Clinical: Twenty-eight patients requiring carotid endarterectomy were chosen at random. Seven patients underwent ultrasonic endarterectomy after traditional access surgery, while 21 patients were treated with conventional endarterectomy. In the clinical study, an intraoperative gross observation of the endarterectomized surfaces was made, followed by duplex scanning after 18 and 24 months. RESULTS: Histologic observation of the cadaveric revealed particularly smooth surfaces in 87.5%; there was no debris, flaps, or vessel damage in any of the ultrasonically treated samples. In contrast, the traditional technique produced regular surfaces without residual debris in only 50% of the experimental cases. Favorable results were also seen in the clinical carotid experience, in which there was no need to surgically correct the ultrasonically endarterectomized surface in any case. In fact, achieving a satisfactory outcome was greatly facilitated by the use of ultrasound. In the conventionally treated patients, however, only 19% (4) demonstrated a smooth luminal surface on gross observation even after surgical correction. No postoperative complications were encountered in either group, and no restenosis has occurred in ultrasonic endarterectomy-treated patients after 2 years. CONCLUSIONS: Favorable experimental results using ultrasonic endarterectomy prompted the successful clinical application of this new technique in carotid stenosis treatment. Whether or not ultrasonic endarterectomy can reduce postoperative morbidity and restenosis is still under study.

Aged↗
PubMed1994

Long term results of interferon treatment in hairy cell leukemia. Italian Cooperative Group of Hairy Cell Leukemia (ICGHCL).

Eighty nine of 104 patients with hairy cell leukemia (HCL), enrolled between 1985 and 1987 in a multicenter prospective study on human lymphoblastoid IFN alpha-n1, were evaluable for long-term follow-up. The induction treatment, 3 MU/mq daily for a median of 5.7 months, produced a response of 93%, complete+partial response (CR+PR) = 80%, minor (MR) = 13%. Neither prior splenectomy nor pre-treatment variables were associated with the rate of response to IFN. However maintenance treatment of 3 MU/mq weekly given randomly had a slightly significant effect on failure free survival (FFS). Of the 43 patients who relapsed, 31/36 (86%) obtained a new response with IFN. No differences in FFS were recorded between first and second response. At the third induction 7/11 patients were treated again with IFN, 4/7 obtaining some response, but the FFS was significantly worse. The overall survival is still 85%. We conclude that (1) IFN should be used as chronic uninterrupted treatment for HCL, (2) reduced dosage is sufficient to prolong the disease free status and (3) continuous lymphoblastoid IFN administration seems not to be associated with the development of resistance to retreatment.

Aged↗
PubMed1994

[Molecular biology and cardiac and vascular changes in hypertension: focus on the renin-angiotensin system].

Arterial hypertension is the leading cause of cardiovascular disease in Western countries. In the last few years a widespread application of molecular medicine techniques has led to unprecedent progress in unravelling both the pathogenetic mechanisms of cardiac hypertrophy and accelerated atherosclerosis as well as the genetical markers of susceptibility to cardiovascular disease. Available data demonstrate the presence of all components of the renin-angiotensin system in the heart and arterial wall and suggest that they may play a crucial role in causing both myocardial hypertrophy and atherosclerosis in hypertension. The current research strategies along with the most recent results in this field are reviewed.

Adult↗
PubMed1994

[Transcatheter arterial chemoembolization technique in cirrhotic patients with hepatocarcinoma. Considerations on the procedure and evaluation of survival].

Two hundred and eight cirrhotic patients with HCC underwent TACE with a standardized technique. Kaplan-Meier survival rates and 12, 24 at 36 months were 62%, 44% and 25%, respectively. Compared with 407 untreated patients, our series had a longer life expectancy, i.e., from 15 months after treatment on. Life experience was statistically different with the L-R test between the groups selected by Child-Pugh cirrhosis staging (p = 0.00000); all 8 Child-Pugh C patients died within 7 months; a high statistical difference was found between Child-Pugh A and B groups (p = 0.00012). Life experience was statistically different with the L-R test between the four groups selected by tumor size and spread (p = 0.012); statistical significance was not reached between contiguous groups in group vs. group comparisons. The patients with monofocal tumors, regardless of size, survive longer than those with multifocal and infiltrative (p = 0.0010) and those with multifocal (p = 0.0029) lesions. Hazard analysis, according to the stratified Cox model, proved tumor-size and Child-Pugh staging to be prognostic factors (p = 0.00027; p = 0.00000) which exhibit a highly significant correlation with each other (p = 0.00000). With the proportional hazard Cox model, tumor characteristics and Child-Pugh stage resulted to be highly significant independent prognostic factors (p = 0.013 and p = 0.000, respectively). Patient survival rates were graphically plotted against literature rates in 407 untreated patients classified by tumor size and by the Child-Pugh method: the two-year survival rates were higher in the subgroups of patients submitted to TACE. To conclude, TACE is an effective treatment not only for multifocal HCCs, but also for large monofocal and infiltrative HCCs. In contrast, TACE is quite useless in the patients with Child-Pugh C cirrhosis.

Adult↗
PubMed1994

[Cystic papillary tumors of the pancreas: 3 new cases].

Three cases of papillary cystic tumor of the pancreas (PCTP) are described. They were observed in two female patients aged 42 and 39, and in a male patient aged 55. A fine-needle ultrasound-guided aspiration biopsy was performed in the man. The cytologic and histologic features turned out to be diagnostic and in compliance with literature data. In the three cases immunohistochemical analyses showed positive reaction to vimentin and alpha-1-antitrypsin. Two cases expressed neuron-specific enolase. Ultrastructural examination revealed similarities between neoplastic cells and normal centroacinar cells of the pancreas. Flow cytometric study revealed a diploid G0/1 peak in two cases. The patients underwent wide surgical excision of the neoplasia. No recurrences or metastases are found with follow-up of 10 years, 8 years and 10 month respectively.

Adult↗
PubMed1994

[Preservation of the pylorus in duodenocephalopancreatectomy in pancreatic and periampullary carcinoma].

The aim of this retrospective study is to evaluate whether the pylorus preserving pancreatoduodenectomy (PPPD) is as safe as the standard Whipple's procedure (PD) in the treatment of pancreatic and periampullary cancer. Between January 1980 and December 1993, 473 patients with carcinoma of the head of the pancreas or periampullary region were admitted to the Department of General Surgery of Pisa University Hospital. 201 of these patients underwent pancreatoduodenectomy (115 ductal carcinoma, 61 periampullary cancer, 25 other neoplasms). In each group patients received a PPPD or a PD (ductal carcinoma 76 PPPD and 33 PD; periampullary cancer 46 PPPD and 15 PD). Overall, postoperative mortality rate for PPPD was 7.5% and for PD 8.9%, decreasing in the last 6 years to 3.2% (3 out of 92 consecutive cases). Variables examined were age, sex, T and N status, tumour stage, histological grade, residual tumour, cancer recurrence, death from recurrence and survival time. No patient was treated with antiblastic therapy. Survival times were estimated for both PPPD and PD using the Kaplan-Meier method and thereafter compared with each other using the Breslow and Mantel-Cox test. The 5-year survival rate in PPPD was 12.3% and 63.01% for ductal and periampullary carcinoma respectively. Survival time was not statistically different between PPPD and PD for both ductal and periampullary cancer. As regards pancreatic cancer, the presence of lymph node metastasis appeared to be a poor prognostic factor, even though it did not reach statistical significance (p = 0.075). In conclusion PPPD may be considered a valid surgical option even when dealing with pancreatic or periampullary cancer.

Adult↗
PubMed1994

[Genetic basis of arterial hypertension: new findings in molecular research methods].

Arterial hypertension is thought to derive from an interaction between genetic and environmental factors. Primary hypertension is currently deemed to be under complete polygenic control but highly heterogeneous both from the genetic and the pathophysiologic standpoint. In the last few years a widespread application of molecular medicine techniques to epidemiological genetic studies has led to unprecedented progress in unravelling the genetical basis of human hypertension. The current research strategies along with the most recent results in this field are reviewed.

Animals↗
PubMed1994

[Arterial hypertension in relation to life style and other cardiovascular risk factors. Epidemiologic study of a population of blood donors. Project AVIS].

The objectives of this research were to determine the prevalence of essential and borderline hypertension in a population of blood donors and their families and to determine if there is a correlation between blood pressure and lifestyle and/or other cardiovascular risk factors. The study was comprised of 1976 individuals, of whom 1290 were men and 686 were women, aged 18-65 years. The prevalence of essential hypertension was 15.1% for males and 12.5% for females: the prevalence of borderline hypertension was 22.3% for males and 15.7% for females. The population was divided into two groups: the first group included only subjects (1170 men, 543 women) who did not regularly use drugs that could modify the blood pressure and the heart rate, the second group included the entire population. In the first group, the multiple regression analysis indicated, in order of importance: age, BMI (body mass index), and heart rate. These variables were important in determining the systolic blood pressure in both sexes, uricemia for males and glycemia for females. The diastolic blood pressure was dependent on BMI, heart rate, and alcohol in both sexes, and glycemia, LDL cholesterol, and uricemia in the men. In the second group, primary and borderline hypertension are significantly correlated with age, BMI, and uricemia in both sexes and glycemia in females. A program of health and nutritional education could modify some factors related to blood pressure, such as obesity and alcohol consumption. The result would be a reduction of the prevalence not only of essential and borderline hypertension, but also of metabolic diseases such as dyslipidaemias, diabetes and hyperuricemia, with a global reduction of the cardiovascular risk.

Adolescent↗