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R Rossi

Publications and source records attributed to R Rossi.

At least 199 records · Page 11Linked to original sources
PubMed1997

Early predictors of late dilation and remodeling after thrombolized anterior transmural myocardial infarction.

BACKGROUND AND HYPOTHESIS: Dilation of the left ventricle after myocardial infarction is associated with an adverse prognosis. There are no clinical studies on the role viable myocardium in the infarcted area assumes in relation to the development of late ventricular remodeling. The hypothesis of this study was to define the relation between remodeling and the presence of viable but akinetic myocardium in the infarct area and to identify early predictors of left ventricular (LV) dilation at 1 year. METHODS: In all, 92 consecutive patients with myocardial infarction were divided into two groups according to their ventricular volumes. Group I included 57 patients with normal volumes at discharge (9 +/- 3 days after acute infarction) and after 12 months or with LV dilation at discharge who had a normalization of their volumes over a 12-month period. Group II included 35 patients who, independent of their initial volumes, developed LV dilation during follow-up. Low-dose dobutamine infusion was utilized at discharge for echocardiographic evaluation of contractile recovery of viable myocardial segments. RESULTS: At the first control, patients in Group I presented an end-diastolic volume index (EDVI) of 100 +/- 7 ml/m2 which decreased to 68.8 +/- 6.5 ml/m2 12 months later (p < 0.0001), and an end-systolic volume index (ESVI) of 47.6 +/- 6.7 ml/m2 at the first control and 30.5 +/- 8.8 ml/m2 after 12 months (p < 0.001). Patients in Group II presented a mean EDVI of 116.2 +/- 8.1 ml/m2 at the first control and 138.8 +/- 8 ml/m2 12 months later (p < 0.001), and a mean ESVI of 68.8 +/- 6.5 ml/m2 at the first control and 79.5 +/- 5.4 after 12 months (p < 0.01). Ventricular mass index (VMI) in Group I increased from 106.4 +/- 11 to 122.3 +/- 15 g/m2 (p < 0.01), while in Group II it decreased from 101.1 +/- 10 to 98.7 +/- 8 g/m2 (p = NS). In Group I, mass-to-volume ratio was 1.15 +/- 0.1 g/ml at the first control and 1.67 +/- 0.1 g/ml 12 months later (p < 0.001), while in Group II it declined from 0.88 +/- 0.1 to 0.69 +/- 0.1 g/ml (p < 0.01). The multivariate analysis revealed that ejection fraction < or = 40%, restrictive filling pattern, wall motion score index > 2.5 in response to dobutamine infusion, and mass-to-volume ratio < or = 1 g/ml, all at discharge, as well as an occluded left anterior descending artery discriminate in favor of late LV dilation and remodeling. CONCLUSIONS: Correct use of noninvasive strategies should result in early identification of postinfarct patients who are at risk of developing LV remodeling.

Aged↗
PubMed1997

Left atrial size is the major predictor of cardiac death and overall clinical outcome in patients with dilated cardiomyopathy: a long-term follow-up study.

HYPOTHESIS: This study was undertaken to determine whether echo-derived left atrial dimension and other echocardiographic, clinical, and hemodynamic parameters detected at the time of entry into the study may influence prognosis in patients with dilated cardiomyopathy during a long-term follow-up. METHODS: This was a prospective cohort analysis of 123 patients with dilated cardiomyopathy. Clinical evaluation, chest x-ray, M-mode and two-dimensional echocardiogram, exercise test, 72-h ambulatory electrocardiogram monitoring, and cardiac catheterization study were performed in all patients. The study was divided into two phases: in the first phase, patients were divided into two groups according to the left atrial size (> or = 45 mm; < 45 mm), with cardiac death as the end point. In the second phase, all patients were further divided into two groups according to their clinical course. A multivariate analysis was performed to determine independent correlated parameters of cardiac mortality and overall clinical outcome. RESULTS: Cardiac mortality rate was 47.9%: 29% in the group without left atrial dilation and 54.3% in the group with dilated left atrium. Multivariate analysis revealed that left atrium > or = 45 mm, New York Heart Association functional classes III/IV, and the presence of one or more episodes of ventricular tachycardia at Holter monitoring were independent predictors of cardiac mortality, while left atrium > or = 45 mm, left ventricular end-diastolic pressure > 17 mmHg, and exercise tolerance < or = 15 min were independent predictors of poor clinical outcome. CONCLUSIONS: Our results revealed that left atrial size is the principal independent predictor of prognosis in patients with dilated cardiomyopathy in that patients with left atrial dilation had an increase in mortality and a worse clinical outcome compared with those without left atrial dilation.

Adult↗
PubMed1997

Piggy-back versus conventional technique in liver transplantation: report of a randomized trial.

Liver transplantation with preservation of the recipient vena cava (the "piggy-back" technique) has been proposed as an alternative to the traditional method. We performed a randomized study on 39 cirrhotic patients, 20 who underwent the piggy-back technique (group 1) and 19 the traditional method using venovenous bypass (group 2) to evaluate the feasibility and true advantages of the piggy-back technique compared to the traditional method. Two patients were switched to the conventional technique due to the presence of a caudate lobe embracing the vena cava in one patient and a caval lesion in the other. Statistically significant differences between the two groups were only found for the warm ischemia time (48.5 +/- 13 min for piggy-back vs 60 +/- 12 min for the conventional method) and for renal failure (zero cases in group 1 vs four cases in group 2). We therefore believe that liver transplantation with the piggy-back technique can easily be performed in almost all cases, and that only a few, specific situations, such as a very enlarged caudate lobe, do not justify its routine use.

Adult↗
PubMed1997

[Early care or quick transport? The effectiveness of preclinical treatment of emergency patients].

"Stay and play," especially in emergency patients with unstable vital functions, offers definite advantages compared to "scoop and run" policies. Typical medical and tactical aspects can be identified to judge the amount of diagnostic and therapeutic measures necessary at the site and during transport. Scoop and run seems to be appropriate only rarely in a area with an emergency medical system in the German style.

Emergency Medical Services↗
PubMed1997

Antioxidant status in various tissues of the mouse after fasting and swimming stress.

We studied the effect of fasting and swimming stress on a number of non-enzymatic and enzymatic antioxidant factors in various mouse tissues in order to see if their action was synergic. We examined levels of reduced (GSH), oxidized (GSSG) and total glutathione, total SH groups (TSH), sum of GSH and protein sulphydryl groups of cytosolic fractions, and the activities of superoxide dismutase (SOD), catalase, glutathione peroxidase, glutathione reductase in adductor muscle, heart and liver. We also studied blood levels of GSH and glutathione bound to protein by mixed disulphides (GSSP). The case series consisted of four groups of animals (n = 10 for each group), namely no swimming and no fast, no swimming and fast, swimming and no fast, and swimming and fast. Fasting (18 h) resulted in a significant GSH depletion in all of the organs studied (-39% in the liver, -30% in the adductor muscle, -21% in the heart); GSSG increased significantly in the heart (+19%). Swimming to exhaustion, which lasted 3.95 (0.18) min [mean (SD), n = 10] with no significant difference between fast and no fast, resulted in a significant GSH depletion, to a percentage lower than that observed after fasting, in the adductor muscle and heart (-12% and -11%, respectively). In the blood of swimming mice, significant increases in GSH (+10%) and GSSG (+21%) levels were observed, whereas GSSP decreased (-15%). Enzyme activities after swimming were modified in only a few cases, and in a complex way. The findings of GSH depletion and a decrease in SOD activity in the adductor muscle seems to confirm the sensitivity of this organ to an overproduction of reactive oxygen species. At the same time, the GSSP decrease observed in blood was a new and unexpected finding, one that indicates a very prompt adaptation of red cells to increased oxidant states.

Animals↗
PubMed1997

Different dysregulations in adrenal steroid biosynthesis as a prevalent cause of hyperandrogenism in women from southern Italy.

OBJECTIVE: To investigate the presence of a dysregulation in steroid biosynthesis in women from southern Italy. DESIGN: Controlled clinical study. SETTING: Normal and hyperandrogenic women referred to the Endocrinology Unit of Federico II University Medical School of Naples. PATIENT(S): One hundred fifty untreated young hyperandrogenic women and 50 normal age-matched women. INTERVENTION(S): Morning (basal) blood samples obtained in the early follicular phase and after a long (360 minute) ACTH stimulation test. MAIN OUTCOME MEASURE(S): The adrenal maximal response was calculated as stimulus under curve areas (AUCa), and all steroids were assayed using RIA methods. RESULT(S): A dysregulation of 21-hydroxylase was found in 22 patients (14.7%), with a prevalent increase of 17 alpha-hydroxyprogesterone AUC, whereas in 9 hirsute women (6%), there was a prevalent significant increase in 11-deoxycortisol AUC. In 5 women (3.3%), DHEA and DHEAS basal and AUCs plasma levels were increased, suggesting an impaired 3 beta-olo-dehydrogenase activity. The remaining 114 hyperandrogenic women (76%) compose the nonadrenal group, with a probable diagnosis of primitive functional ovarian hyperandrogenism. CONCLUSION(S): Considering the high prevalence of hirsutism and oligomenorrhea in our female hyperandrogenic population, we suggest an adrenal hyperresponsiveness likely due to a dysregulation in enzymes related to androgen adrenal steroidogenesis.

17-alpha-Hydroxyprogesterone↗
PubMed1997

Relationship between atrial function, left ventricular isovolumic relation time, and early filling in dual chamber-paced patients.

This investigation was performed to study atrial systolic function is response to modification of atrioventricular delay in a sample of 36 patients with a DDD pacemaker implanted for complete atrioventricular block. The relation between atrial systolic performance and diastolic-related parameters was also evaluated. Isovolumic relaxation time, early diastolic peak velocity, late (atrial) diastolic peak velocity, atrial filing fraction, and atrial ejection force were recorded at a pacing rate of 70 impulses/min and at atrioventricular delay of 200, 150, and 100 msec. Our data showed that the progressive shortening of atrioventricular delay induced a gradual increase in early peak velocity (median value 46 to 53 to 61.5 cm/sec, respectively, at 200, 150, and 100 msec intervals) and a gradual decrease in isovolumic relaxation time (median 92.6 to 81.5 to 69.7 msec at 200, 150, and 100 msec, respectively), atrial peak velocity (59 to 52 to 44.5 cm/sec at 200, 150, and 100 msec, respectively), atrial filling fraction (50.5% to 40% to 23.5% at 200, 150, and 100 msec, respectively), and atrial ejection force (17.2 to 14.7 to 8.5 kilodynes at 200, 150, and 100 msec, respectively). For every atrioventricular delay value detected, we found a significant correlation between isovolumic relaxation time and early peak velocity with atrial filling fraction and atrial ejection force. In addition, atrial ejection force was related directly to atrial filling fraction at studied atrioventricular delays. The two indexes of atrial systolic performance showed a parallel decrease by shortening the atrioventricular delay, and they can quantify atrial systolic performance equally in sequentially paced patients. Furthermore, our results are in accordance with the hypothesis that the interaction between the effectiveness of active left atrial emptying and isovolumetric relaxation time may play an important role in maintaining an ideal ventricular filling despite changes in atrial systolic function.

Aged↗
PubMed1997

Differential circadian eating patterns in two psychogenetically selected strains of rats fed low-, medium-, and high-fat diets.

Spontaneous eating patterns in male, inbred Roman high- and low-avoidance rats (RHA/Verh, RLA/Verh) were continuously recorded while animals were successively offered three isocaloric (approximately 16.5-kJ/g) diets: a low-fat, high-carbohydrate diet (LF; 3.3% fat), a medium-fat diet (MF; 18% fat), and a high-fat diet (HF; 40% fat), the latter being followed once again by the LF diet. Under the conditions of this experiment, overall 24-h food intake did not differ significantly between RHA/Verh and RLA/Verh rats, but was significantly higher for both rat strains on the MF and HF diets than on the LF diet. Despite the similar 24 h-food intake, RHA/Verh rats ate transiently less than RLA/Verh rats during the third quarter of the dark phase under all dietary conditions. These differences were due to the RHA/Verh rats' longer intermeal intervals (with all diets) and smaller meals (with the MF and HF diets) and were compensated for during the last 3 h of the dark phase. On the LF diet, dark-phase meal frequency was higher and both nocturnal meal size and mean eating rate within meals were lower in RLA/Verh rats than in RHA/Verh rats. With the MF and HF diets, mean nocturnal meal size and meal duration were higher and mean eating rate was lower in RLA/Verh rats than in RHA/Verh rats. For both strains, nocturnal meal size was significantly higher with the MF and HF diets than with the LF diet, and nocturnal meal frequency was lower with the HF diet than with the other two diets. Although body weights were similar at the start of the study, RLA/Verh rats gained significantly more weight than did RHA/Verh rats by the end. As has often been the case with other aspects of behavior studied, differences in neuromodulatory systems (e.g., serotoninergic and dopaminergic) between RHA/Verh and RLA/Verh rats may directly or indirectly contribute to the subtle differences in eating patterns observed here.

Analysis of Variance↗
PubMed1997

G-cell density in the antral mucosa: a feasibility study.

In this work a new method for gastrin-secreting cell (G-cell) density measurement was employed in order to test the hypothesis that G-cell density of the antral mucosa can be estimated with an acceptable degree of error. The zone of antral mucosa where most G-cells are located was demarcated, its area was measured and the G-cells within this area were counted. The variation in the e error of the estimate according to normal distribution theory, and the size of the sampling expected to yield G-cell density values with a given error were assessed. Our data indicate that a very large surface of the G-cell zone should be explored in order to estimate G-cell density with an acceptable degree of error. G-cell density measurement appears not to be feasible on biopsy specimens or, for routine diagnosis, on gastrectomy specimens.

Aged↗
PubMed1997

Comparison of methods for personal sampling of inhalable and total lead and cadmium-containing aerosols in a primary lead smelter.

It has been proposed that future occupational aerosol exposure standards be based on particle size-selective sampling criteria that more accurately reflect worker exposure. In relation to methods currently used for determining individual workers' lead exposures, the widely used 37-mm, closed-face, plastic sampling cassette is known from laboratory wind tunnel studies to undersample significantly compared with estimations of aerosol actually inhaled, especially for large particles. The present study investigated the degree to which this is borne out in field sampling by using side-by-side sampling in selected work sites in a primary lead smelter. Exposures to "total" airborne lead and cadmium as measured using the 37-mm sampler (E37) were compared with exposure measurements using the institute of Occupational Medicine (IOM) personal inhalable aerosol sampler (EIOM). There were 166 good sample pairs for lead and 55 for cadmium. The ratio (reflecting the fractional undersampling of the 37-mm sampler, as represented by the ratio EIOM/E37) was consistently greater than unity, by factors obtained by regression analysis ranging (for different parts of the plant) from 1.39 to 2.14 for lead and 1.29 to 2.12 for cadmium. The factor tended to be greater for parts of the plant characterized by coarser aerosol, consistent with the physical sampling characteristics of the two instruments. This research is important (1) in assessing the impact of implementation of new standards for lead- and cadmium-containing aerosols in the primary lead production industry, and (2) in the development of new occupational exposure limits based on the inhalable aerosol fraction.

Aerosols↗
PubMed1997

Parasitic sinusitis and otitis in patients infected with human immunodeficiency virus: report of five cases and review.

We describe five cases of parasitic sinusitis and otitis in patients infected with human immunodeficiency virus (HIV) and review 14 reported cases. The pathogens identified in our group of patients included agents such as Microsporidium, Cryptosporidium, and Acanthamoeba species. The clinical features common to these patients included a long history of HIV seropositivity associated with advanced immunosuppression and multiple opportunistic infections as well as long-standing local symptoms refractory to multiple courses of antibacterial agents. Symptoms often included fever and chills in addition to local tenderness and discharge. Invasive diagnostic procedures were necessary to obtain the final diagnosis and to initiate appropriate therapy. Although most patients responded at least partially to specific therapy, relapses and recurrences were frequent in patients who did not receive long-term suppressive therapy. The general outcome for HIV-infected patients with parasitic sinusitis and otitis was poor; however, deaths were generally associated with other complications of the underlying HIV infection.

AIDS-Related Opportunistic Infections↗
PubMed1997

Food-associated drinking in pygmy goats: importance of histamine receptors.

The combined effect of the histamine receptor antagonists Dexbrompheniramine (DXB: H1-receptor antagonist) and Cimetidine (C: H2-receptor antagonist) on food and water intake was investigated in pygmy goats. DXB (1 mg/kg BW0.75) and C (16 mg/kg BW0.75) were injected together intraperitoneally (i.p.). Cumulative food and water intake, as well as meal and draft pattern, were recorded. DXB and C significantly reduced cumulative water intake, whereas cumulative food intake did not change. Water to food ratio was also significantly diminished. Draft frequency and the percentage of drafts associated with meals were significantly reduced during the 6 h post injection, while meal frequency and meal size did not change during this period. The results show that blockade of the H1- and H2-histamine receptors attenuates the association between water and food intake in pygmy goats. Therefore, mechanisms responsible for meal-associated drinking seem to depend upon activation of histamine receptors.

Animals↗
PubMed1997

Hyperpolarization of hepatocytes by 2,5-AM: implications for hepatic control of food intake.

Because 2,5-anhydro-D-mannitol (2,5-AM) seems to stimulate feeding by acting on the liver and because the hepatic membrane potential has been suggested to play an important role in control of feeding ("potentiostatic" hypothesis), we investigated the effect of 2,5-AM on the membrane potential of liver cells with microelectrodes using a superfused liver slice technique. 2,5-AM (2.5 mM), which reduces intracellular ATP in rat liver, hyperpolarized the liver cell membrane in mouse and rat liver slices by 4-7 mV. This hyperpolarization was reversed by quinine (1 mM), an unspecific blocker of Ca2+-dependent K+ channels, and abolished by apamin (20 nM), a blocker of Ca2+-activated K+ channels with low conductance. Amiloride at 10(-3) M, but not at 10(-6) M, or a low-Na medium (26 mM) also eliminated the hyperpolarization. The K+ channel blockers cetiedil (50 microM), glibenclamide (30 microM), and Ba2+ (5 mM); flufenamic acid (100 microM), a blocker of nonselective cation channels; and ouabain (1 mM), an inhibitor of the Na+-K+-adenosinetriphosphatase, did not significantly influence the 2,5-AM-induced hyperpolarization. It is concluded that 2,5-AM hyperpolarizes the liver cell membrane by activating Ca2+-dependent K+ channels. This activation seems to be impaired when the Na+/H+ exchanger is inhibited by amiloride or a low-Na+ medium. The findings also imply that the hyperphagic effect of 2,5-AM observed in rats is not associated with a decrease in the hepatic membrane potential, as postulated by the potentiostatic hypothesis.

Amiloride↗
PubMed1997

Squamous carcinoma in situ of the ovary.

We report a case of a squamous cell carcinoma in situ of the ovary in a patient previously submitted to radical hysterectomy and pelvic lymphadenectomy for an epidermoid carcinoma of the uterine cervix. The histogenesis of epidermoid tumors of the ovary and their association with squamous malignancies of the uterine cervix are discussed.

Adult↗
PubMed1997

Effect of duration of ampullary gallstone obstruction on severity of lesions of acute pancreatitis.

BACKGROUND: This study was done to determine the effects of duration of obstruction on severity of lesions in patients with acute pancreatitis of biliary origin. STUDY DESIGN: This case controlled study used patient data collected prospectively on protocol during a 27-year period in a university teaching hospital. We studied a group of 97 patients with acute pancreatitis, all with an impacted stone at the ampulla of Vater at exploration (Group Ob), and a control group of 49 patients with acute gallstone pancreatitis who experienced spontaneous ampullary disobstruction within 24 hours from the onset of symptoms and who showed a patent ampulla at exploration (Group Cont). Duration of obstruction was defined as the time elapsed between the onset of symptoms and exploration in Group Ob, and from the onset of symptoms until the appearance of signs of ampullary disobstruction in Group Cont. Severity of disease in both groups was determined by the appearance of the pancreas at exploration. Patients in Group Ob were divided into three subgroups according to duration of obstruction: under 24 hours, 25 to 48 hours, and more than 48 hours. RESULTS: The incidence of severe pancreatic lesions was higher in Group Ob than in Group Cont (19.7 percent compared to 6.1 percent, p < .01). Mean duration of obstruction was also significantly longer in Group Ob than in Group Cont (42.4 hours compared to 10.6 hours). In the subgroups of patients whose obstruction lasted under 48 hours, the incidence of severe lesions was low: in the 24 hours or fewer group, severe lesions were observed in 8.1 percent (3 of 37); and in the 25 to 48 hours group, the incidence was 10.6 percent (5 of 47). Neither subgroup differed significantly from Group Cont (6.1 percent, 3 of 49). When duration of obstruction exceeded 48 hours, however, frequency of severe lesions increased significantly to 84.6 percent (11 of 13) (p < .001). CONCLUSIONS: The findings in this study suggest that duration of ampullary obstruction is a major factor determining the severity of pancreatic lesions: severe pancreatic lesions are rare in patients whose obstruction lasts not more than 48 hours. In contrast, pancreatic necrosis develops in nearly all patients with obstruction beyond 48 hours. It may be safe to treat patients conservatively during the first day of the illness. If obstruction is not resolved by the second day, endoscopic retrograde cholangiopancreatography or surgical intervention must be carried out.

Adolescent↗
PubMed1997

Quiescence, cycling, and turnover in the primitive hematopoietic stem cell compartment.

Continuous oral bromodeoxyuridine (BrdU) administration was used for the non-invasive measurement of the in vivo cell cycling characteristics of hematopoietic stem and progenitor cell populations of increasing maturity, isolated on the basis of their relative levels of Rhodamine 123 (Rh) and Hoechst 33342 (Ho) fluorescence. The results showed that whereas primitive hematopoietic stem cells (PHSCs) are hierarchically ordered on the basis of quiescence, the most primitive of these, characterized by their Rh/Ho(dull) phenotype and their capacity for long-term hematopoietic reconstitution, are not dormant, but cycle slowly in normal steady-state bone marrow (BM). Cell cycle analysis showed that 30 +/- 7% of Rh/Ho(dull) PHSCs had cycled and incorporated BrdU following continuous administration over 1 week, whereas 60 +/- 14% and 89 +/- 3% of these cells were BrdU positive at 4 and 12 weeks, respectively. Linear regression analysis of these data showed that Rh/Ho(dull) PHSCs cycle with an average turnover time of 4.3 weeks (30 days), and a t1/2 (time to 50% cycled) of 2.75 weeks (19 days).

Animals↗