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Biomedical subjects

A Ferrari

Publications and source records attributed to A Ferrari.

At least 253 records · Page 14Linked to original sources
PubMed1991

Effects of long-term treatment with naltrexone on hepatic enzyme activity.

The influence of naltrexone on liver function in heroin addicts was studied, with respect to the metabolizing function by using the antipyrine clearance and to cellular damage by monitoring plasma levels of hepatic enzymes. The clearance of antipyrine was not affected by naltrexone treatment, and, during the study period, the use and withdrawal of benzodiazepines and alcohol did not change this parameter; moreover, there was no relationship between changes in plasma hepatic enzymes and antipyrine half-life. Mean plasma levels of hepatic enzymes did not show significant modification in the course of treatment with naltrexone.

Administration, Oral↗
PubMed1991

Snapping hip: a rare form with internal etiology.

"Internal" extraarticular snapping hip, rare and often misdiagnosed, can cause functional limitation of the hip and severe gait disturbances. It is provoked by the iliopsoas tendon which catches on the lesser trochanter or the iliopectineal eminence, as in the case described in this paper. Standard surgical treatment consists in lengthening the tendon, and the authors suggest an inguinal approach.

Adult↗
PubMed1991

[Indications and results of transcatheter ablation and surgery in paroxysmal reentry nodal tachycardia].

In patients with nodal tachycardia refractory to medical therapy, transcatheter or surgical ablation is necessary. From January 1989 to December 1990, in 26/42 patients with nodal tachycardia, referred to our institution for electrophysiologic evaluation, transcatheter ablation by radiofrequency (20 patients) or surgical ablation by perinodal cryo (6 patients) was performed. In all these cases, a total refractoriness to several antiarrhythmic drugs alone or in association had been observed. The radiofrequency current, generated by the Osypka HAT 100 device, was administered through a tripolar USCI 7 F catheter. The ideal site for energy delivery was defined on the basis of a mapping, performed in the A-V junction area. In order to find out the most premature retrograde atrial activation, the following areas were explored: right bundle, atrial His bundle, peri-nodal region, proximal His bundle and coronary sinus ostium. Local atrial activation time was evaluated during nodal tachycardia by delivering a premature ventricular extrastimulus to discover the atrial deflection from the ventricular one. In the selected area, 5 applications (range 1-12) of 20-25 W power radiofrequency energy for 5-30 s were delivered on average. A complete prevention of nodal tachycardia was achieved in 18/20 patients (90%). Only in 2 patients a total A-V block was induced. The pre- and post-procedure values are as follows: AH: pre 71 +/- 19, post 113.6 +/- 50; HV: pre 45.5 +/- 8, post 47 +/- 6; aWP: pre 353 +/- 57, post 391 +/- 87; rWP: pre 322 +/- 58, post 411 +/- 58. In 10/18 cases the AH interval was normal after radiofrequency application.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1991

Regulation of hepatic transferrin, transferrin receptor and ferritin genes in human siderosis.

Although many studies have examined the regulation of transferrin, transferrin receptor and ferritin subunit gene expression in experimental systems, no molecular biological data in humans have been documented to date. In this study we simultaneously analyzed the hepatic content of transferrin, transferrin receptor and heavy and light ferritin subunit messenger RNAs in tissue samples obtained from subjects with normal iron balance and patients with primary or secondary iron overload. Steady-state levels of transferrin messenger RNA were not depressed by iron overload. On the contrary, they were increased (p less than 0.001) in patients with severe hepatic siderosis (liver iron content greater than 200 mumol/gm dry wt) as compared with the control group. This indicates that, as already suggested by our previous data in experimental siderosis, iron maintains the ability to induce transferrin gene activity even when cellular iron content is significantly increased. Transferrin receptor gene expression was found to respond in the same manner to any cause of iron-tissue load, regardless of the cause. In fact, a lower signal for transferrin receptor messenger RNA was consistently detected in iron-overloaded patients vs. control subjects, particularly in patients with thalassemia major and idiopathic hemochromatosis (p less than 0.001). Ferritin light-subunit messenger RNA accumulation was significantly increased in those patients with severe siderosis (idiopathic hemochromatosis and thalassemia major = liver iron between 200 and 600 mumol/gm dry wt). The fact that no significant change in hepatic ferritin heavy-subunit gene expression was detected in iron-loaded patients confirms preferential production of light-subunit--enriched ferritins in long-term iron overload.(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗
PubMed1991

Sympathovagal interaction during mental stress. A study using spectral analysis of heart rate variability in healthy control subjects and patients with a prior myocardial infarction.

We tested the hypothesis that psychological stress testing in the clinical laboratory provokes changes in the sympathetic and vagal activities regulating heart rate that can be assessed noninvasively using spectral analysis of RR variability. To account for the effects on respiration produced by talking, this study was performed with two different procedures: the I.K.T. (i.e., a computer-controlled mental task that is performed in silence and does not entail human confrontation) and a stressful interview. Finally, we assessed whether ischemic heart disease modifies the spectral changes induced by psychological stress by comparing a group of healthy subjects (age, 38 +/- 2 years) with a group of patients (age, 52 +/- 3 years) recovering from 1-month-old myocardial infarctions. The findings indicate that psychological stress induced marked changes in the sympathovagal balance, which moved toward sympathetic predominance. The low-frequency component of RR variability, a marker of sympathetic activity, increased from 58 +/- 5 normalized units (NU) to 68 +/- 3 NU with the I.K.T. and to 76 +/- 3 NU with the interview. This increase was absent in the group of post-myocardial infarction patients. However, arterial pressure increased significantly in both groups of subjects. The possibility of age playing an important role in determining the differences observed was disproved by the findings of a marked increase in low frequency with mental stimuli in an additional group of borderline hypertensive subjects with ages (55 +/- 2 years) comparable to those of post-myocardial infarction patients.

Adult↗
PubMed1990

Analysis of short-term oscillations of R-R and arterial pressure in conscious dogs.

We studied the neural determinants of the second (i.e., high frequency, HF)- and third-order (i.e., low frequency, LF) spontaneous oscillations of heart period (R-R interval) and arterial pressure (AP) in conscious dogs, with the hypothesis that they might furnish quantitative markers of autonomic controlling activities. Spectral analysis of simultaneous R-R and AP variabilities quantified these oscillations that were also evaluated in units normalized by total power to focus on the balance of these two major components. At rest we observed a prevalent HF component (approximately 0.25 Hz) in R-R and AP variabilities that was synchronous with respiration. This HF component of R-R variability disappeared after atropine infusion and can be considered a marker mostly of vagal activity. When baroreceptor unloading, obtained by moderate hypotension, increased sympathetic activity the LF component increased in R-R, systolic, and diastolic AP variabilities. This increase in LF was not present after ganglionic blockade or after chronic arterial baroreceptor denervation. After chronic bilateral stellectomy, hypotension was not accompanied by an increase in LF component of R-R variability, while LF component remained in AP variability. An increase in LF component of R-R and AP variabilities was observed during transient coronary artery occlusion.

Animals↗
PubMed1990

Disseminated intravascular coagulation and myocardial infarction in a haemophilia B patient during therapy with prothrombin complex concentrates.

A case of disseminated intravascular coagulation (DIC) and fatal myocardial infarction in a haemophilia B patient is described. DIC occurred after 4 days of therapy with unactivated prothrombin complex concentrates during the post-operative period. Therapy with fresh frozen plasma, heparin and antithrombin III concentrates was started without efficacy; after autopsy myocardial infarction was evident.

Blood Coagulation Factors↗
PubMed1990

[Doppler flowmetry in the study of portal hypertension in patients with liver cirrhosis. Qualitative and quantitative analyses].

The recent development of the duplex-Doppler technique, which combined real-time US with pulsed Doppler flowmetry, has allowed the flowmetric hemodynamic study of large abdominal vessels. As yet, however, both accuracy and possible applications of this method in the study of portal hypertension have not been fully investigated. This study was aimed at assessing whether or not the combined use of Doppler flowmetry and bidimensional US is able to detect portal hypertension in patients with liver cirrhosis (LC), and could therefore represent a valid alternative to endoscopic, angiographic, and direct pressure measurement techniques. Twenty-six patients with LC and 25 control patients were studied with a strictly standardized method; portal hypertension was detected in the patients with LC by EGDS and laparoscopy. The results demonstrated pulsed duplex-Doppler US to be able to detect portal hypertension in 92.4% of LC patients, with 2 false negatives only (7.6%). The difference in the flowmetric data of normal and LC patients was highly significant (p less than 0.001 Student's t test). In conclusion, duplex-Doppler US can be considered as a valid technique to detect portal hypertension in LC patients, and can thus be used as an alternative to more invasive techniques of general use in clinics.

Adult↗
PubMed1990

[Defibrotide in the prevention of deep venous thrombosis in gynecologic surgery. A controlled study versus calcium heparin in 120 patients].

The efficacy of defibrotide and calcium heparin in the prevention of Deep Vein Thrombosis (DVT) in gynecological surgery were compared in a randomized study. Seventy patients candidate to gynecological surgery (for benign conditions) and 50 candidate to surgery for malignancies were randomly allocated either to defibrotide (400 mg b.i.d. IM from the day before operation to the 7th postoperative day, n = 60) or to calcium heparin (5000 IU t.i.d. SC from the operation to the 7th postoperative day, n = 70). The diagnosis of DVT was made with impedance plethysmography and if necessary confirmed with phlebography. No patient developed established DVT in either groups and no adverse reactions were observed. These results indicate that defibrotide may be considered as an alternative to heparin in the DVT prophylaxis in gynecological surgery.

Female↗
PubMed1990

[Percutaneous transhepatic sphincterotomy].

The authors describe the technique employed for percutaneous transhepatic sphincterotomy as performed on 3 patients with common bile duct (CBD) stones. In all patients, previous endoscopic attempt had failed for anatomical reasons (Billroth II gastric resection or partial gastric resection with Brown anastomosis), and the ampulla could not be correctly incannulated with the sphincterotome. In all patients endoscopy was useful to check the position of the diathermic loop inserted percutaneously. Complete and immediate success was obtained in all 3 cases. No major complications occurred during transhepatic treatment. To date, 1 recurrence has been observed, and the patient has been retreated with bilioplasty. All patients were followed after 5-6 months with US, plain X-rays of the abdomen and blood tests (gamma Gt, alkaline phosphatase, and bilirubinemia). The authors suggest that percutaneous transhepatic sphincterotomy be employed electively in patients with biliary tree diseases in case the endoscopic approach failes.

Aged↗
PubMed1989

Colorectal adenomas containing invasive carcinoma. Pathologic assessment of lymph node metastatic potential.

Adenomas that contain early invasive carcinoma (ACIC) represent the earliest form of clinically relevant cancer of the colorectum in most patients. In order to assess the incidence of nodal metastases of ACIC, we studied 31 patients in whom the colon was resected after endoscopic polypectomy (EP) done from 1975 to 1987. We also reviewed the pathologic features reported in individual cases and in literature series of ACIC with lymph node metastases published from 1958 to 1986. The lymph node metastatic potential of ACIC is relatively high, ranging from an average value of 8.5% in the literature of to 16.1% in our own study, and is equivalent to the range of 10%-17% that occurs in colorectal carcinomas that invade the submucosa. When an ACIC is seen in an EP specimen in which the polypectomy margin is normal, the decision as to whether the patient should enter a follow-up protocol or have radical surgical resection is determined by the assessment of the probability of the occurrence of nodal metastases. According to several authors, certain histopathologic features make it possible to distinguish between an ACIC with a high-risk of nodal metastases versus those with a low-risk. The most relevant pathologic parameters include the state of the resection margins, the grade of the invasive carcinoma, and the presence or absence of vascular invasion. Of 351 cases of ACIC that were operated on, derived from 16 literature series, 45.6% were high-risk cases and 8.5% had lymph node metastases. In our group of high-risk ACIC that had surgical resection subsequently, the lymph node metastatic rate was 35.7%. Our results help to estimate the nodal metastatic potential of early colorectal carcinomas and stress the importance of adequate pathologic evaluation in order to assess metastatic risk in these patients accurately.

Adenoma↗
PubMed1989

Characterization of a novel mouse reticular cell sarcoma M5076 subline resistant to cisplatin.

A novel murine tumor resistant to cis-diamminedichloroplatinum (cisplatin, DDP) was obtained (M5/DDP) after 22 passages in which mice bearing the ovarian reticular cell sarcoma M5076 (M5) were treated with DDP. Although DDP conserved some inhibitory activity on growth of M5/DDP, it was much less effective than on M5. Treatment with DDP did not prolong the survival time of mice with M5/DDP, whereas it markedly prolonged survival of M5-bearing mice. M5 and M5/DDP tumors shared many biological and biochemical features. They were similar histologically, they metastasized reproducibly to the liver and were poorly immunogenic. Their growth rates were comparable; their DNA index, percentage of cells in S phase and intra-cellular glutathione content were also similar. In both tumors, DDP caused an accumulation of cells in S late-G2-M within 24 hr after drug treatment. However, this was efficiently reversed in M5/DDP, whereas it worsened and persisted longer in M5. Cross-resistance was observed between DDP and its analogues carboplatin and iproplatin, but tetraplatin retained marginal activity on M5/DDP tumor. Several alkylating agents tested [L-phenyalanine mustard (L-PAM); cyclophosphamide (CTX); chlorambucil (CLB); 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) and dacarbazine (DTIC)] were not totally cross-resistant to DDP, but showed greater activity on M5 than on M5/DDP. Other non-alkylating anti-neoplastic drugs showed a similar degree of activity on M5 and M5/DDP. 5-Aza-2'-deoxycytidine (Aza-d-Cyd) was very effective on both tumors, etoposide (VP-16) and cytosine arabinoside (Ara-C) had no activity and Adriamycin (ADR) was weakly effective.

Animals↗
PubMed1989

Biological osteosynthesis in osteochondral lesions of the talus.

Osteochondral lesions of the dome of the talus whether medial or lateral are rare. Surgical treatment is required when there is a loose body, or when the lesion is symptomatic and resistant to nonsurgical treatment. Usually, the degenerated fragment is removed, followed by curettage and multiple perforations of the subchondral bed, but different methods may be used to reinsert the osteocartilaginous fragment. Having been satisfied with our first studies conducted both on animals and man, we began to reinsert the osteochondral fragment by using resorbable means of synthesis. The purpose of this study is to report our experiences with 3 such cases at a minimum follow-up of one year.

Adolescent↗
PubMed1989

[Prevention of acute neonatal respiratory insufficiency. A method of conditioning the baboon lung during cesarean section].

Preterm baboons at 140 +/- 3 day gestation (term 182 +/- 7 days) have been subjected to lung conditioning, consisting of a series of prolonged inflations of the lungs at 35 cm H2O, followed by approximately 10 min of application of continuous positive airway pressure (CPAP) equal to 15-20 cm H2O, before umbilical cord interruption. The aim of this study was to evaluate, in a primate experimental model, the safety and efficacy in the prevention of neonatal RDS of a technique so far experimented on only in ovine models. Thoraco-pulmonary compliance exceeded the value of 0.2 ml (cm H2O)-1.kg-1 in only 1 animal out of 5 (20%), which didn't develop illness, versus 69% of positive results achieved with the same technique in lambs at 128-130 day gestation, an experimental model considered in the literature as equivalent to a 140 +/- 3 day gestation baboon as far as it concerns incidence and severity of RDS. The application of lung conditioning was easy and safe (as previously reported), but its effectiveness in a primate model is still to be defined.

Animals↗