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Biomedical subjects

G Benzi

Publications and source records attributed to G Benzi.

At least 19 recordsLinked to original sources
PubMed1992

Natural history of small untreated hepatocellular carcinoma in cirrhosis: a multivariate analysis of prognostic factors of tumor growth rate and patient survival.

We analyzed the growth pattern of tumor masses and the survival of 39 asymptomatic Italian patients with a total of 59 small (less than or equal to 5 cm in diameter) hepatocellular carcinomas arising from cirrhosis. The total length of the observation period ranged from 90 to 962 days, with an average of 364 +/- 229 (mean +/- S.D.). Doubling time ranged from 27.2 to 605.6 days (mean +/- S.D., 204.2 +/- 135; median = 171.6 days). Three different growth patterns were recognized: (a) tumors with no or very slow initial growth pattern (doubling time greater than 200 days), 10 cases (37%); (b) tumors with declining growth rate over time, 9 cases (33.4%); and (c) tumors with almost constant growth rate, 8 cases (29.6%). Using the stepwise discriminant analysis, we found a score based on albumin, alcohol intake, number of nodules, echo pattern and histological type that allowed a correct prediction of short doubling time (less than or equal to 150 days) in 55.6%, medium doubling time (151 to 300 days) in 60% and long doubling time (greater than 300 days) in 100% of cases. The estimated survival rate of the 39 patients, calculated by the Kaplan-Meier method was 81% at 1 yr, 55.7% at 2 yr and 21% at 3 yr. Stepwise discriminant analysis showed that a score based on sex, HBsAg status, alcohol consumption, ascites, gamma-glutamyltranspeptidase, prothrombin time, Child-Pugh class and all the sonographical parameters could predict 2-yr survival in 100% of cases. We conclude that great variability of growth patterns exists among and within small hepatocellular carcinomas. Prediction of subsequent growth rate is unreliable in most cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Alcohol Drinking↗
PubMed1992

Outbreak of recurrent abdominal cramps associated with Arcobacter butzleri in an Italian school.

In the autumn of 1983, an outbreak of recurrent abdominal cramps occurred in a nursery and primary school in the Rovigo area in Italy. None of the 10 affected children had diarrhea. An atypical Campylobacter-like organism was isolated from feces in all cases. Conventional enteropathogens were searched for but not detected. The Campylobacter-like organism was identified as Arcobacter butzleri by using sodium dodecyl sulfate-polyacrylamide gel electrophoresis of whole-cell proteins and cellular fatty acid analysis. Its identity was confirmed by DNA-DNA hybridizations versus Arcobacter reference strains. All of the preserved outbreak strains have identical protein profiles and phenotypic characteristics and belong to serogroup 1 of the Lior serotyping scheme on the basis of slide agglutination of crude and absorbed antisera of A. butzleri reference strains versus heat-labile antigens of live bacteria. These data point to an epidemiological relationship. The successive timing of the cases suggests person-to-person transmission.

Campylobacter↗
PubMed1992

Ultrasonography and guided biopsy in the diagnosis of hepatocellular carcinoma.

Ultrasonographic screening and follow-up of patients with chronic liver disease lead to the detection of a large number of small asymptomatic hepatocellular carcinomas, so that the changing appearance of this neoplasm during its natural history has now been recognized. Ultrasonography provides information on shape, echogenicity, growth pattern and vascular involvement of the neoplasm. Three different shapes may be identified, depending upon the size and the invasiveness of the neoplasm: nodular, massive and diffuse. The echogenicity is variable and the tumour mass may appear hypo, hyper or isoechoic in comparison with the surrounding liver tissue. A mixed pattern and/or a hypoechoic ring may also be visualized. A tendency to change from a low echo pattern to a low periphery and finally to a massive pattern with increasing echogenicity has been shown in Japanese patients. The infiltrative growth pattern may be grossly distinguished from the expansive one on the basis of the aspect of the tumour boundary. Vascular invasion is easily recognizable as a mass within a major portal branch or even in the portal trunk. Duplex and color Doppler ultrasonography enable further insights on the vascular alterations related to this neoplasm. Abnormal signals, typical of HCC, are characterized by high-peak with broadening of spectrum. Low impedance continuous signals are less characteristic. Finally, ultra-sound guidance allows puncture of intrahepatic nodules as small as 1cm. The sensitivity of this procedure in the diagnosis of focal liver lesions is very high, varying between 91% and 95% with a specificity of 92%-100%.

Biopsy↗
PubMed1992

[Clinical study for the evaluation of the tolerability of O-(beta-hydroxy-ethyl)-rutoside in the treatment of hemorrhoids during the 3d trimester of pregnancy and in the postpartum period].

Hemorrhoidal disease is particularly frequent in the last trimester of pregnancy and immediately after birth. The aim of the present study was to evaluate the efficacy and tolerability of high doses of O-(beta-hydroxyethyl)-rutoside in patients affected by this pathology. Forty-two women with hemorrhoid varices of varying severity which had appeared during the last trimester of pregnancy or immediately post-partum were treated by administering 3 g/day of the substance in question for 14 consecutive days. At the start and end of treatment a series of clinical and objective parameters were measured and at the end of treatment efficacy and tolerability were assessed. The latter was found to be excellent; in fact, it was not necessary to suspend treatment in any of the subjects treated. Clinical efficacy, assessed by the researcher, was judged to be positive in 95% of cases treated. Clinical improvements in the parameters examined were statistically significant (p < 0.01). The results obtained confirm the value of oral therapy using O-(beta-hydroxyethyl)-rutoside in pregnant or puerperal patients since the preparation was found to be efficacious and easily managed, above all significantly reducing pain, subjectively the most urgent symptom to be treated.

Adult↗
PubMed1991

Age-related acute depletion of cerebral glutathione by peroxidative stress.

Cyclohexene-1-one and cycloheptene-1-one cause a severe age-related depletion of reduced glutathione (GSH) in the forebrain of 5- or 15- or 25-month-old rats. Chronic pretreatment with phosphatidylcholine partially inhibits the GSH depletion in old forebrains by the prooxidants tested, suggesting that in aged animals alterations in mitochondrial inner membrane phospholipid composition and/or cytochrome oxidase activity might play a role in oxygen free-radical production.

Aging↗
PubMed1991

Sequential damage in mitochondrial complexes by peroxidative stress.

The biochemical characteristics of the electron transfer chain are evaluated in purified non-synaptic ("free") mitochondria from the forebrain of 60-week-old rats weekly subjected to peroxidative stress (once, twice, or three times) by the electrophilic prooxidant 2-cyclohexene-1-one. The following parameters are evaluated: (a) content of respiratory components, namely ubiquinone, cytochrome b, cytochrome c1, cytochrome c; (b) specific activity of enzymes, namely citrate synthase, succinate dehydrogenase, rotenone-sensitive NADH: cytochrome c reductase, cytochrome oxidase; (c) concentration of reduced glutathione (GSH). Before the first peroxidative stress induction, the rats are administered for 8 weeks by intraperitoneal injection of vehicle, papaverine, delta-yohimbine, almitrine or hopanthenate. The rats are treated also during the week(s) before the second or third peroxidative stress. The cerebral peroxidative stress induces: (a) initially, a decrease in brain GSH concentration concomitant with a decrease in the mitochondrial activity of cytochrome oxidase of aa3-type (complex IV), without changes in ubiquinone and cytochrome b populations; (b) subsequently, an alteration in the transfer molecule cytochrome c and, finally, in rotenone-sensitive NADH-cytochrome c reductase (complex I) and succinate dehydrogenase (complex II). The selective sensitivity of the chain components to peroxidative stress is supported by the effects of the concomitant subchronic treatment with agents acting at different biochemical steps. In fact, almitrine sets limits to its effects at cytochrome c content and aa3-type cytochrome oxidase activity, while delta-yohimbine sets limits to its effects at the level of tricarboxylic acid cycle (citrate synthase) and/or of intermediary between tricarboxylic acid cycle and complex II (succinate dehydrogenase).(ABSTRACT TRUNCATED AT 250 WORDS)

Almitrine↗
PubMed1991

Trends in multiple births in Italy: 1955-1983.

On the basis of the numbers of single and multiple births routinely collected by the Central Institute of Statistics, trends in multiple births in Italy over the period 1955-1983 were analyzed. Between 1955 and 1983 the frequency of multiple births declined by about 25% (from 12.6/1000 deliveries to 9.6/1000 deliveries). The downward trend was constant until the early 1970s when rates tended to level off and increase slightly. This finding was largely attributable to trends in dizygotic rates, monozygotic births being approximately constant over the period considered. Multiple birth rates rose till age 35-39, being more than two times higher in this age group than in teenagers, but flattened off in the subsequent strata of age: this finding was constant over the period considered. Despite the general decreasing trend, the regional differences persisted largely unchanged, multiple birth rates being about 30% higher in Southern (and less developed areas) of the country than in the North of Italy. Geographic differences were limited to dizygotic pregnancies, monozygotic rates being constant (about 4/1000 pregnancies) in various areas.

Adolescent↗
PubMed1991

Caliber of splenic and hepatic arteries and spleen size in cirrhosis of different etiology.

The caliber of the splenic and hepatic arteries, the hepatic to splenic artery ratio and the spleen size (area of widest spleen section) were evaluated by real time ultrasonography (US) in 88 patients affected by liver cirrhosis of different etiology (26 alcoholic cirrhosis, 43 hepatitis B virus (HBV) related cirrhosis, 8 cryptogenic cirrhosis and 11 primary biliary cirrhosis) and in a control group of 21 normal subjects, in order to assess the possible influence of the etiology of the disease on these morphological parameters. The mean caliber of the hepatic artery was larger, and the mean caliber of the splenic artery smaller in alcoholic than in HBV-related, cryptogenic and in primary biliary cirrhosis. This difference is emphasized when considering the hepatic to splenic artery ratio: this parameter was never greater than 0.9 in all cases of primary biliary cirrhosis, in 38 out of 43 patients with HBV-related cirrhosis and in 6 out of 8 cryptogenic cirrhosis, while in the alcoholic group only in one out of 26 was it less than 0.9. The sensitivity, specificity and accuracy of this ratio in differentiating alcoholic from non-alcoholic cirrhosis was 96%, 88% and 91%, respectively. Splenomegaly resulted more in primary biliary cirrhosis, in HBV-related cirrhosis and in cryptogenic cirrhosis than in the alcoholic form. Finally, a significant correlation was found in all groups of cirrhotic patients between the diameter of the splenic artery and the spleen size. These results show that some ultrasonographic morphological features of liver cirrhosis differ according to its varied etiology, probably reflecting different pathophysiological mechanisms.(ABSTRACT TRUNCATED AT 250 WORDS)

Diagnosis, Differential↗
PubMed1991

Liver cirrhosis: changes of Doppler waveform of hepatic veins.

The authors compared the Doppler ultrasonographic pattern of hepatic veins (HVs) in a group of 60 patients affected by liver cirrhosis and in 65 healthy subjects comparable for sex and age to (a) detect possible differences in HV waveform in the two groups and (b) investigate the relationship of these differences with the severity of the disease (according to Child-Pugh classification) and the modifications of systemic hemodynamics. The waveform of HVs was arbitrarily classified into three patterns: HV0, a normal waveform; HV1, lower oscillations without the reversed phase; and HV2, completely flat waveform. The resistivity index of the superior mesenteric artery, reflecting the peripheral splanchnic impedance and the hyperdynamic circulation, was also measured in a subgroup of 45 cirrhotic patients. The waveform of HVs in all healthy subjects corresponded to the HV0 pattern. Among cirrhotic patients, HV0 was found in 30 (50%), HV1 in 19 (31.7%), and HV2 in 11 (81.3%). The severity of functional impairment was greatest in the HV2 group and least in the HV0 group. This was significantly correlated with the decrease of the resistivity index in the superior mesenteric artery in the subgroup of 45 patients. Changes in the normal HV waveform could be considered a useful adjunctive tool for the noninvasive evaluation of liver disease. The pathophysiology of these changes in HV blood flow is still unclear. The significant correlation with the severity of the disease and with the decrease of splanchnic resistances indicates that these changes in the HV waveform occur in the presence of marked rearrangements of liver tissue and of hyperdynamic systemic circulation.

Adult↗
PubMed1990

Evaluation of prevalence of "doping" among Italian athletes.

To evaluate knowledge of, attitudes to, and use of illegal drugs and other forms of "doping" in sport 1015 Italian athletes and 216 coaches, doctors, and managers (technicians) were interviewed after selection on a quota basis. Overall, 30% of athletes, managers, and coaches and 21% of doctors indicated that athletic performance can be enhanced by drugs or other doping practices. Over 10% of athletes indicated a frequent use of amphetamines or anabolic steroids at national or international level, fewer athletes mentioning blood doping (7%) and beta-blockers (2%) or other classes of drugs. These proportions were 2-3 times higher for occasional use than for frequent use. Estimates by managers and coaches were much the same as those of athletes when allowance was made for larger random variation. 62% of athletes who acknowledged doping reported pressure to do so from coaches and managers. According to over 70% of athletes access to illegal substances was not difficult. Both athletes and technicians awarded higher scores to risk than to efficacy for any substance, although 42-67% of athletes and technicians regarded amphetamines and anabolic steroids as efficacious. 82% wanted stricter controls not only during competitions but also during training.

Adolescent↗
PubMed1990

Influence of oxidative stress on the age-linked alterations of the cerebral glutathione system.

The glutathione system (reduced and oxidized glutathione; redox index) was studied in the forebrain of male Wistar rats of 5, 15, and 25 months of age following the administration for 2 months in drinking water of chemicals that induce oxidative stress: paraquat and diethyldithiocarbamate (DDC) to increase superoxide radical formation, aminotriazole and hydrogen peroxide to increase hydroxyl radical generation, as well as diamide and ferrous chloride to decrease the glutathione cycle activity. Chronic oral administration of phosphatidylcholine for 2 months was evaluated in 25-month-old rats. Aging accentuated the changes produced by chemicals that induce oxidative stress; i.e., the changes in the glutathione redox index were most pronounced in the forebrains of the older paraquat-, DDC-, H2O2-, and diamide-treated rats. Markedly different adaptative changes occurred within the various drug groups. The reduced glutathione was increased (by paraquat, DDC and aminotrazole), decreased (by H2O2) or unchanged (by iron and diamide). Furthermore, in older rats, paraquat and DDC increased the glutathione redox index, whereas H2O2 and diamide decreased the glutathione redox index or were ineffective (i.e., aminotriazole, iron). The glutathione redox index altered by chronic drug administration was modified by the concomitant administration of phosphatidylcholine.

Administration, Oral↗
PubMed1990

Influence of aging and drug treatment on the bioenergetics of hypoxic brain.

Synaptosomes isolated from the forebrain of rats of different ages (20, 60 and 100 weeks of age) were incubated in Krebs-Henseleit-Hepes (pH 7.4) buffer, for 10 min at 24 degrees C. The energetic state was defined by the redox state of the intramitochondrial NAD-couple (delta Gox-red) and the phosphorylation state of adenine nucleotide system (delta GATP). The biological energy "lost" by the system during the coupled reactions was estimated by the delta delta G = delta Gox-red - delta GATP. The animals were submitted for 10 min to different degrees of in vivo hypoxia. To elucidate the mechanism of action, the effect of the pretreatment with drugs acting on oxygen availability (almitrine) or on microcirculation and metabolism (delta-yohimbine) was tested. In synaptosomes isolated from the forebrain of animals submitted to moderate degree of hypoxia (oxygen arterial partial pressure ranging between 32 and 29 mmHg) the efficiency of the system was quite similar to that observed in normoxia, with the exception of the older rats. In synaptosomes isolated from the forebrain of rats submitted to severe degree of hypoxia (oxygen arterial partial pressure ranging between 20 and 18 mmHg) the efficiency of the system was markedly altered as a function of both aging and severity of hypoxemia. The pretreatment with the agent increasing the oxygen availability partially modified the efficiency of the system, the alpha-blocking agent being less important. The drug action was markedly related to both the age and the degree of hypoxia.

Adenosine Triphosphate↗
PubMed1990

Endometrioma of the liver.

Hepatic endometriosis is extremely rare. We describe a patient sent to us with epigastric pain as the only symptom and who was found to have associated endometrioma of the liver and left ovary. We suggest a gynecologic evaluation before surgery for hepatic cyst of unknown cause.

Adult↗
PubMed1990

Factors involved in the age-related alteration in the efficiency of the brain bioenergetics.

The synaptic energy state may be defined by the redox state of the intramitochondrial NAD-couple (delta Gox-red) and the phosphorylation state of adenine nucleotide system (delta GATP). The biological energy 'lost' by the system during the coupled reactions is calculated as delta delta G = delta Gox-red-delta GATP. These evaluations are performed in synaptosomes isolated from the forebrain of rats of different ages (20, 60 and 100 weeks of age) and incubated in Krebs-Henseleit-Hepes (pH 7.4) buffer, for 10 min at 24 degrees C. The animals are submitted for 10 min to different degrees of in vivo hypoxia. To better elucidate the mechanism of action, the effects of the pretreatment with agents inducing vasodilation (papaverine), or acting on cerebral carbohydrate metabolism (hopanthenate), or on neurotransmission and cerebral metabolism (theniloxazine) are tested. In synaptosomes isolated from the forebrain of animals submitted to moderate degree of hypoxia (PaO2 = 32-29 mmHg) the efficiency of the system is quite similar to that observed in normoxia, with the exception of the older rats. In synaptosomes isolated from the forebrain of rats submitted to severe degree of hypoxia (PaO2 = 20-18 mmHg) the efficiency is altered as a function of both aging and severity of hypoxemia. Drug pretreatment may partially interfere with the delta delta G by hypoxemia, the action being related to the rat age and hypoxic degrees. The age-related decrease in the efficiency of the coupled states seems to be related to alteration in the phosphorylation state of adenine nucleotides.

Adenine Nucleotides↗
PubMed1990

Age-related modifications of cytochrome C oxidase activity in discrete brain regions.

The apparent Km for cytochrome c of cytochrome oxidase does not change but the Vmax decreases in synaptosomes and non-synaptic mitochondria isolated from the cerebral cortex as a whole of 30-month-old rats compared with 4-month-old ones. When the subcellular organelles are submitted to stressful conditions, namely incubation in media of altered osmolality, the percentage of cytochrome oxidase activity released is much higher in senescent rats. The activity of cytochrome oxidase evaluated in non-synaptic mitochondria and synaptosomes isolated from cortical and subcortical regions and cerebellum of rats aged 4 and 30 months shows a highly significant decrease (P less than 0.001) in the parietotemporal cortex of senescent rats (both in non-synaptic mitochondria and synaptosomes) and in the cerebellum (in synaptosomes).

Age Factors↗
PubMed1990

Role of synaptosomal enzymatic alterations and drug treatment in brain aging.

The activity patterns of enzyme linked to energy transduction are measured as an estimate of the energy potential capacity of the brain during aging. Early investigations provided information on age-related modifications in the apparent activity of these enzymes in the brain as a whole without taking into account the anatomical, morphological, and functional heterogeneity of the discrete brain regions, the metabolic compartments, and their different time course of aging processes. These considerations prompted the investigators to focus their efforts on subcellular organelles, representative of metabolic compartments, isolated from selected brain regions. In the present study, to better elucidate the role of the synaptic compartment during aging, the maximum rate (Vmax) of enzymes involved in energy metabolic pathways is evaluated in synaptosomes isolated from the cerebral cortex of rats aged 4, 12, and 24 months. The potential catalytic activity of phosphofructokinase and citrate synthase is not affected by aging. In contrast, the Vmax of pyruvate dehydrogenase and particularly of cytochrome oxidase decreases in aged rats. A marked increase is found in the Vmax of glucose-6-phosphate dehydrogenase in 24-month-old rats and could support the availability of nicotinamide adenine dinucleotide phosphate (NADPH) for antiperoxidative processes. Pretreatments of the animals with certain drugs are performed in order to check the responsiveness of the tissue and the plasticity of enzyme proteins during aging. Papaverine (acting on macrocirculation) is ineffective, but raubasine (acting on microcirculation and metabolism) and almitrine (acting on oxygen availability) both interfere with the potential activity of some of the enzymes tested. Their influence differs with the age of the animal and are in agreement with their action on brain carbohydrate and phospholipid metabolism.

Aging↗
PubMed1990

Arachidonic acid metabolism and pathophysiologic aspects of subarachnoid hemorrhage in rats.

We studied the ex vivo production of prostaglandin D2, prostaglandin E2, 6-ketoprostaglandin F1 alpha, and leukotriene C4 in the brain tissue of rats subjected to experimental subarachnoid hemorrhage. The ex vivo method allows the study of arachidonic acid metabolites released from brain slices at different times after subarachnoid hemorrhage induction and reflects the residual capacity for arachidonic acid metabolism after the pathologic event. The rats were sacrificed 30 minutes, 1 and 6 hours, and 2 days after subarachnoid hemorrhage was induced by the injection of 0.30 ml autologous arterial blood into the cisterna magna. Concentration of prostaglandin D2 and 6-ketoprostaglandin F1 alpha was increased significantly relative to control 2 days after induction. The concentration of prostaglandin E2 was increased significantly 6 hours after induction, while ex vivo production of leukotriene C4 was increased significantly at 1 and 6 hours and 2 days. The correlation between these results and the occurrence of vasospasm after subarachnoid hemorrhage is discussed. The results obtained from the ex vivo incubation of brain tissue slices after experimental subarachnoid hemorrhage suggest that after the hemorrhage there is a significant modification of brain eicosanoid metabolism, which could be of great importance in interpreting the pathogenesis of subarachnoid hemorrhage-related neuronal impairment.

Animals↗