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Biomedical subjects

R Russo

Publications and source records attributed to R Russo.

At least 55 records · Page 3Linked to original sources
PubMed1997

Role of tissue renin in the regulation of aldosterone biosynthesis in the adrenal cortex of nephrectomized rats.

The aim of the study was to investigate whether the adrenal renin-angiotensin system plays an independent role in the regulation of mineralocorticoid biosynthesis in the adrenal gland and to explore the mechanisms of this action. Twelve-week-old male Sprague-Dawley rats were studied: 22 rats were maintained on a regular diet; 27 and 22 rats received a low salt diet with and without treatment, respectively, with the angiotensin II (Ang II) AT1-subtype receptor antagonist losartan (10 mg/kg per day). A fraction of each group of rats underwent bilateral nephrectomy (n = 12, 15, and 10, respectively) and was killed 48 hours later. In an additional group of 24 (12 intact and 12 nephrectomized) rats, the effects of the Ang II AT2-subtype receptor antagonist PD123319 were investigated. In intact rats, plasma renin activity (PRA) and adrenal renin activity and expression were progressively raised by salt restriction and losartan, whereas aldosterone synthase mRNA and plasma aldosterone (PA) levels were increased by salt restriction and reduced by losartan. Forty-eight hours after nephrectomy, PRA fell to undetectable levels; in contrast, adrenal renin expression, assessed by semiquantitative reverse-transcriptase polymerase chain reaction (using GAPDH as a standard for gene expression), showed an 18-fold increase and was further increased after salt restriction and losartan (all P < .05). Also, adrenal renin activity was raised after nephrectomy and further increased after salt restriction (P < .05) and losartan. Cytochrome P450 aldosterone synthase expression in the adrenal cortex was stimulated by nephrectomy alone and by nephrectomy combined with low salt intake (P < .05), with consequent increases in PA concentrations. In losartan-treated salt-restricted nephrectomized rats, cytochrome P450 aldosterone synthase expression (P < .05 versus nephrectomy alone and nephrectomy plus salt restriction) and PA concentrations were diminished (P < .05) in spite of the observed increases of adrenal renin expression. The AT2-receptor antagonism did not significantly affect PRA, adrenal renin, and aldosterone biosynthesis and production in either intact or nephrectomized salt-restricted rats. These results demonstrate that the adrenal renin-angiotensin system plays an independent role in the regulation of mineralocorticoid biosynthesis in vivo. This action is mediated primarily via the Ang II AT1-subtype receptors.

Adrenal Glands↗
PubMed1997

Epidemiologic surveillance of visceral leishmaniasis in Sicily, Italy.

Visceral leishmaniasis (VL) is endemic in Sicily. Although it is a notifiable disease, there is evidence that the actual number of cases is higher than that reported. In 1987, a regional reference center for active surveillance of VL was established and it recorded a total of 284 cases through 1995, a mean of 31.5 cases/year and about four-fold more than previously reported. Of the 284 cases, 150 (53%) were children (< or = 14 years of age), and of the 134 adults, 39 (29%) were coinfected with human immunodeficiency virus (HIV). The commonest viscerotropic zymodeme of Leishmania infantum, MON 1, was identified in 40 (93%) of 43 HIV-negative and eight (57%) of 14 HIV-positive patients. Among 280 patients evaluated (i.e., all HIV-negative and 35 of 39 HIV-positive subjects), 254 (91%) were treated with meglumine antimoniate alone or in combination with other drugs; 23 (8%) received allopurinol or amphotericin B, either conventional or in liposomal form; and three terminally ill patients were not treated. Among the 245 HIV-negative patients, 236 (96%) were successfully cured, while nine (4%) (seven adults) died during the course of antimonial treatment. None of the 35 HIV-positive patients was definitively cured, although mortality was apparently associated with other opportunistic infections.

Adolescent↗
PubMed1997

[Static functional study with magnetic resonance of anterior shoulder instability].

We studied the glenohumeral joint, in its different components, with cine MRI. Ten asymptomatic volunteers and 6 patients with recurrent shoulder instability were examined with T2-weighted GE MR sequences on the axial plane with the subjects' arms rotated in different positions. The sections corresponding to the subcoracoid space and bicipital groove were recorded in closed-loop video format for cine display. Normal morphological glenoid labrum changes were demonstrated in different degrees of humerus rotation. The subscapularis tendon and the capsule were redundant and infolded toward the joint on internal rotation in 4/6 patients. We found capsular detachment in 2 patients, humeral head subluxation in 3 and subcoracoid impingement in 2 patients. Cine MRI permitted the accurate study of the changes in the glenoid labrum, capsule and subscapularis tendon in all patients and it also showed narrowed coracohumeral distance (< 11 mm) on internal rotation.

Humans↗
PubMed1997

p53 expression compared with other prognostic factors in OMS grade-I stage-Ta transitional cell carcinoma of the bladder.

OBJECTIVE: Recent studies have investigated the possibility that p53 protein and some macroscopic tumoral features, such as diameter and focality of the lesion, play a significant prognostic role in bladder cancer progression. A retrospective study was conducted on papillary grade-I stage-Ta transitional cell carcinoma (TCC) of the bladder. METHODS: p53 expression was evaluated using the immunohistochemical method. A group of 31 patients with papillary grade-I and stage-Ta TCC of the bladder with no recurrence or who recurred with no histological grading and staging variation in a 4-year mean follow-up period was compared with 28 grade-I and stage-Ta papillary TCC patients who underwent recurrences and a worsening in histological grading (grade II or grade III) or staging (T1) within the same period of time. The aim of this study was to investigate the hypothesis that altered patterns of expression of the protein products of the mutated p53 tumor-suppressor gene, when independently evaluated in comparison with other tumoral prognostic factors, are associated with tumor recurrence and progression in patients with Ta papillary grade-I TCC of the bladder. RESULTS: Our data show that when a p53 threshold of > 0% was considered, 53.6% of patients with tumor progression in the follow-up period were p53-positive compared with only 16.1% of the nonprogressing group (chi 2 = 6, p = 0.02). On the contrary, p53 failed to show any value in predicting progression when a 5% threshold was considered (chi 2 = 1.12, p = 0.92). The multifocality of the tumoral lesion and recurrent tumor was highly predictive of tumor progression for both variables (chi 2 = 5.16, p = 0.003, and chi 2 = 0.23, p = 0.006, respectively). Multivariate analysis revealed p53 nuclear overexpression (at a threshold of > 0%) to be a single valuable prognostic factor of progression (OR = 10.20, p = 0.009) and recurrence (OR = 54.19, p = 0.01). CONCLUSIONS: Our results lead to the conclusion that p53 immunohistochemical detection has no prognostic value in predicting tumoral relapse or progression of TaGI TCC of the bladder when a 5% positivity threshold is considered. On the contrary, when a p53 nuclear labelling of > 0% is considered as positive staining, this tumor marker becomes highly predictive of tumor recurrence and progression. These findings seem therefore to suggest the use of a slight p53 positivity (> 0%) as a valid tool in predicting the clinical behavior of TaGI bladder TCC. The prognostic impact of a multifocal lesion and a recurrent tumor as markers of progression is also confirmed by these results.

Aged↗
PubMed1997

Protein and amino acid metabolism in splanchnic organs in metabolic acidosis.

Metabolic acidosis causes a cooperative participation of different organs such as the liver, kidney, and muscle in restoring acid-base balance. In splanchnic organs, metabolic acidosis has repercussions on several nitrogen metabolism pathways. The decrease in urea synthesis due to reduced activity of urea cycle enzymes, ammonia uptake and amino acid transport, and changes in glutamine metabolism support renal ammoniagenesis thus offering a response to rid the body of excess protons. While some of the mechanisms are adaptive others may be harmful for the body. Metabolic acidosis may have effects on splanchnic protein turnover. In severe acidosis, synthesis of secreted liver proteins may be reduced. Acidosis may also modulate the response of the liver to growth hormone (GH) for insulin-like growth factor-I synthesis, thus inducing a state of GH resistance. Splanchnic abnormalities in acidosis might contribute to the malnutrition observed in uremia.

Acidosis↗
PubMed1997

[Doppler color US in the diagnosis and treatment of iatrogenic pseudoaneurysms].

Pulsatile masses occur increasingly as a complication of transfemoral or transaxillary percutaneous catheterization, as the number of catheterization procedures and their complexity has increased. These iatrogenic injuries may be represented by a pseudoaneurysm or by a periarterial hematoma with transmitted arterial pulsation: the 2 vascular injuries require prompt differentiation because pseudoaneurysms need treatment by means of US-guided compression or surgical repair. Nineteen patients (10 men and 9 women, aged 40-85 years, mean: 62 years) with a groin (no. = 17) or axillary (no. = 2) pulsatile mass following angiographic catheterization were prospectively examined with color Doppler sonography (US). A pseudoaneurysm was detected in 13 patients (12 femoral and one axillary injury), whereas the other 6 pulsatile masses were consistent with periarterial hematomas. US-guided compression was attempted in 13 pseudoaneurysms and the pulsatile mass was repaired in 11/13 cases (84.6%), including 10/12 femoral and 1/1 axillary lesions. All the vascular injuries successfully treated with US-guided therapy were repaired 1-4 days after the angiographic complication. On the other hand, two pseudoaneurysms unsuccessfully treated with US-guided compression were studied after 8 and 24 days, respectively, after the angiographic complication and subsequently submitted to surgical repair. The pseudoaneurysms size did not seem to affect the favorable outcome of the US-guided treatment. With the exception of the 2 surgical cases, the other 17 patients underwent clinical examination and color Doppler US one and 7 days after the US-guided compression of the pulsatile mass. Moreover, a 6-25 weeks clinical follow-up showed no late complications or recurrences in all the cases. In conclusion, color Doppler US is now the technique of choice to assess potential complications related to femoral or brachial artery catheterization.

Adult↗
PubMed1996

Kidney, splanchnic, and leg protein turnover in humans. Insight from leucine and phenylalanine kinetics.

The rate of kidney protein turnover in humans is not known. To this aim, we have measured kidney protein synthesis and degradation in postabsorptive humans using the arterio-venous catheterization technique combined with 14C-leucine, 15N-leucine, and 3H-phenylalanine tracer infusions. These measurements were compared with those obtained across the splanchnic bed, the legs (approximately muscle) and in the whole body. In the kidneys, protein balance was negative, as the rate of leucine release from protein degradation (16.8 +/- 5.1 mumol/min.1.73 m2) was greater (P < 0.02) than its uptake into protein synthesis (11.6 +/- 5.1 mumol/min. 1.73 m2). Splanchnic net protein balance was approximately 0 since leucine from protein degradation (32.1 +/- 9.9 mumol/min. 1.73 m2) and leucine into protein synthesis (30.8 +/- 11.5 mumol/min. 1.73 m2) were not different. In the legs, degradation exceeded synthesis (27.4 +/- 6.6 vs. 20.3 +/- 6.5 mumol/min. 1.73 m2, P < 0.02). The kidneys extracted alpha-ketoisocaproic acid, accounting for approximately 70% of net splanchnic alpha-ketoisocaproic acid release. The contributions by the kidneys to whole-body leucine rate of appearance, utilization for protein synthesis, and oxidation were approximately 11%, approximately 10%, and approximately 26%, respectively; those by the splanchnic area approximately 22%, approximately 27%, and approximately 18%; those from estimated total skeletal muscle approximately 37%, approximately 34%, and approximately 48%. Estimated fractional protein synthetic rates were approximately 42%/d in the kidneys, approximately 12% in the splanchnic area, and approximately 1.5% in muscle. This study reports the first estimates of kidney protein synthesis and degradation in humans, also in comparison with those measured in the splanchnic area, the legs, and the whole-body.

Adult↗
PubMed1996

Association and cosegregation of stroke with impaired endothelium-dependent vasorelaxation in stroke prone, spontaneously hypertensive rats.

While hypertension is a major risk factor for stroke, it is not its sole determinant. Despite similar blood pressures, spontaneously hypertensive rats (SHR) do not share the predisposition to cerebrovascular disease typical of stroke-prone spontaneously hypertensive rats (SHRSP). We investigated vascular function in male SHR and SHRSP as well as in SHRSP/SHR-F2 hybrid animals. Animals were maintained on the appropriate dietary regimen necessary for the manifestation of stroke. Among the hybrid animals, a group of stroke-prone and a group of stroke-resistant rats were selected. Blood pressure was similar in all groups. Endothelium-independent vascular reactivity tested on isolated rings of thoracic aorta and basilar artery after death showed similar contractile and dilatory responses to serotonin and nitroglycerin, respectively, in all groups. In contrast, endothelium-dependent relaxation, in response to acetylcholine or substance P, was markedly reduced in SHRSP compared with SHR. Similarly, reduced vasodilatory responses were present in aortae of F2 rats that had suffered a stroke when compared with SHR or F2 rats resistant to stroke. The observed association and cosegregation of stroke with significant and specific impairment of endothelium-dependent vasorelaxation among SHRSP and stroke-prone F2 hybrids, respectively, suggest a potential causal role of altered endothelium-dependent vascular relaxation in the pathogenesis of stroke.

Acetylcholine↗
PubMed1996

Comparison of the indirect immunofluorescent antibody test and the direct agglutination test for serodiagnosis of visceral leishmaniasis in HIV-infected subjects.

One hundred subjects positive for anti-human immunodeficiency virus (HIV) antibodies were tested for anti-Leishmania antibodies by the indirect immunofluorescent antibody test (IFAT) and the direct agglutination test (DAT). Subjects were subsequently followed for two years to monitor the onset of visceral leishmaniasis. Fifteen subjects were positive for anti-Leishmania antibodies in either one or both tests. Eleven were positive only by IFAT, one only by DAT, and three by both tests. During the two-year follow-up period, nine subjects developed visceral leishmaniasis; of these, six were serologically positive, four by IFAT alone and two by both tests. The results indicate that IFAT and DAT have a similar specificity but that IFAT has a higher sensitivity and a greater diagnostic significance.

Adult↗
PubMed1996

Comparative effects of growth hormone on water and ion transport in rat jejunum, ileum, and colon.

Specific growth hormone (GH) receptors are located along the entire rat intestine. We have recently shown that GH induces water and ion absorption in the rat ileum. This raises the possibility that GH regulates water and ion transport throughout the intestine. To test this, we have evaluated the effects of GH administration on jejunal, ileal, and colonic water and ion transport, by the in vivo rat perfused intestine, and in vitro, in corresponding segments of intestine mounted in Ussing chambers. In vivo, GH increased water absorption by 250%, 180%, and 80% over baseline in the jejunum, ileum, and colon, respectively. The effect had similar kinetics in the three intestinal regions. In vitro, serosal GH administration induced a decrease in short-circuit current, consistent with an absorptive effect. The effect showed a proximal to distal decreasing pattern. These findings suggest that GH plays a role in the body fluid homeostatic control, promoting water and ion absorption.

Animals↗
PubMed1996

Laparoscopic choledochotomy with primary closure. Follow-up (5-44 months) of 31 patients.

BACKGROUND: Thirty-three patients were candidates for laparoscopic choledochotomy. The indications for this operation are described. METHODS: The procedure was completed 32 times (97%). We had 29 successful common bile duct (CBD) clearances, three negative explorations, and one failed clearance which needed to be converted to laparotomy. All the completed procedures ended with primary closure of the main duct. Median duration of surgery was 180 min (range 100-300), including three associated laparoscopic procedures. RESULTS: There were three postoperative complications (9.4%), none major. Average postoperative hospital stay was 7.1 days (range 4-14). In May-June 1995 we controlled 31 out of the 32 consecutive patients (one patient was lost to follow-up) who had a successful laparoscopic choledochotomy from October 1991 to December 1994. Median follow-up was 22 months (range 5-44). Besides clinical control, 23 patients also had ultrasound (US) controls and 24 had blood tests. Eleven had intravenous cholangiotomography. Two patients died 11 and 22 months after the operation for unrelated causes and without biliary symptoms. Two patients had umbilical hernias. One had a small residual asymptomatic stone, which was removed endoscopically. None had signs of postoperative CBD stricture. At US, CBD was </=7 mm in 15 patients, 8-10 mm in four patients, and 10-12 mm in three patients. The last group had preoperative CBD dilation, too. We could compare preoperative and postoperative CBD diameters in 22 patients: 11 had no change; in nine it decreased; and two had a slight increase (8-10 mm). CONCLUSIONS: We conclude that laparoscopic choledochotomy with primary closure is a very good operation: It has a high success rate and low morbidity. Mortality is nil so far. Medium-term results are very positive: We had no CBD stricture and only one case of asymptomatic residual stone, which could have been avoided. Our results suggest that intraductal biliary drainage is useless, and its specific complications are well known.

Adult↗
PubMed1996

Visceral leishmaniasis in HIV infected patients: treatment with high dose liposomal amphotericin B (AmBisome).

Visceral leishmaniasis (VL) in patients coinfected with human immunodeficiency virus (HIV) is often atypical, and characteristically relapses after treatment. We treated 10 HIV infected patients (9 men) with parasitologically confirmed VL with liposomal amphotericin B ("AmBisome': L-AMB) at a dose of 4 mg/kg/day on days 1, 2, 3, 4, 5, 10, 17, 24, 31, and 38. Patients were hospitalized for the first 5 days, and were monitored during, and 1 week and 1, 3 and 6 months after, L-AMB therapy. There were no serious adverse events, and L-AMB was well tolerated. 9/10 patients completed therapy, one patient defaulted at day 24. Clinical improvement was seen in all nine patients and the bone marrow aspirate was cleared of visible/culturable parasites in 8/9 patients. During follow-up, one patient defaulted. The seven remaining patients relapsed at 2, 3, 3, 5, 5, 6 and 7 months. Re-treatment with a variety of antileishmanial drugs was unsatisfactory. The time from first diagnosis of VL to death in six patients was 5-40 months (mean 18.8 months). Only one patient remained alive 26 months after treatment. L-AMB is safe and provides a good initial clinical response. Intermittent dosing enables a short period of hospitalization. However, relapse is probably inevitable.

AIDS-Related Opportunistic Infections↗
PubMed1996

Defective 'gut processing' of gliadin in mice with graft-versus-host enteropathy.

The gut mucosa plays an important role in the induction of oral tolerance. Extending previous observations, we have here shown that serum containing gut-absorbed gliadin induces suppression of the specific systemic immune response in recipient mice parenterally immunized with gliadin. Graft-versus-host reaction (GvHR) has profound effects on the gut mucosa, representing a model of immune-mediated enteropathy. The aim of our work was to investigate the gut handling and processing of gliadin in mice with GvHR. Binding to enterocytes, passage through the epithelium, and ability of the epithelium to convert this antigen into a tolerogenic form were assessed in BDF1 mice weaned on gluten-free diet, 2 weeks after the induction of a semiallogeneic GvHR. Binding of gliadin peptide B3144 to enterocytes was similar in controls and GvHR mice. After feed, serum levels of gliadin were comparable in the two groups of mice, but when serum collected from GvHR mice and containing gut-absorbed gliadin was transferred intraperitoneally into naive recipient mice, this did not induce suppression of the specific immune response. These experiments indicate that during GvHR enteropathy the ability of the intestine to convert gliadin into a tolerogenic form is lost. Defective antigen gut processing may contribute to the observed failure in oral tolerance induction.

Animals↗
PubMed1996

Evaluation of c-ras oncogene product (p21) in superficial bladder cancer.

OBJECTIVES: The aim of our study is the evaluation of the prognostic importance of p21 protein in superficial bladder cancer. METHODS: One hundred and fourteen patients with an initial diagnosis of monofocal bladder cancer (stage Ta-T1) following TUR were investigated. On the tissue removed by TUR, besides the usual pathological evaluation, an immuno-histochemical investigation was carried out in order to ascertain the presence of c-ras oncogene product (protein p21). The actuarial curves concerning the time free from the first recurrence were computed, comparing different subgroups in regard to protein p21 presence, grade and stage of the tumour. RESULTS: The analysis of the results shows the importance of tumour stage as a predictor of recurrence, as well as that of the presence of c-ras products. This last factor increases the risk of recurrence almost 2-fold, in the same time lag, for c-ras-positive patients (p < 0.001). The prognostic significance of c-ras is independent of stage. CONCLUSION: Our data underline the possibility of acquiring important information on the prognosis of superficial bladder cancer patients, pointing out the significance of c-ras oncogene product.

Actuarial Analysis↗
PubMed1996

Muscle protein turnover in chronic renal failure patients with metabolic acidosis or normal acid-base balance.

It is currently unknown if metabolic acidosis has any effect on muscle protein metabolism in patients with chronic renal failure (CRF). To address this question, muscle protein turnover was studied in patients with CRF and controls in the postabsorptive state by using the forearm perfusion method together with the 3H-phenylalanine kinetics. Nine patients were acidotic ([HCO-3]a = 20 +/- 0.5 mEq/l) whereas 4 patients had a normal acid-base balance ([HCO-3]a = 25 +/- 0.3 mEq/l). In patients with metabolic acidosis the rates of phenylalanine appearance and disposal from the forearm were increased as compared to controls. Phenylalanine net balance, i.e. net proteolysis, was only slightly higher than in controls. In patients under a normal acid-base balance both rates of appearance and disposal of phenylalanine as well as phenylalanine net balance were similar to controls. These preliminary data suggest that metabolic acidosis can enhance the rate of muscle protein degradation in patients with CRF.

Acidosis↗
PubMed1996

[The clinical experiences of abortions on demand in a group of 221 adolescents].

The authors studied about planned abortion performed by girls under 19 years of age, during the period 1991-1994. The aim of this study was to evaluate the entity of planned abortion also concerning the number of adolescent pregnancy. Our study show the percentage of pregnancy was progressively diminished, while regarding the planned abortion even if reduced along the time, the percentage remain steady in the course of years examined.

Abortion, Legal↗