PubMed Health⌕ Search

Biomedical subjects

F Raimondi

Publications and source records attributed to F Raimondi.

At least 37 records · Page 2Linked to original sources

[Hypertension and peripheral arterial hemodynamics].

Sixty uncomplicated hypertensive patients (40 stable and 20 borderline) were studied, by strain gauge plethysmography, in comparison with 25 normotensive subjects, in order to evaluate the arterial hemodynamics of the lower limbs in essential hypertension and to verify the different pattern in borderline and in stable hypertensives. Resting blood flow, even if lightly decreased in hypertensive groups, didn't show significant differences in its mean values; Peak Flow, instead, was reduced proportionally to the severity of hypertension in all the hypertensive patients, but only in the stable hypertensives did it prove statistically significant. Minimal Vascular Resistances showed a similar behaviour; they were significantly increased only in the stable hypertensives, whereas Basal Vascular Resistances, were raised in all hypertensive patients, in the borderline group too. Finally, half time and total hyperemic time, which indicate vascular reactivity, were significantly decreased in all hypertensives. These results suggest that the stable hypertensive patients principally develop arterial structural changes, while the borderline hypertensive patients have only functional modifications, such as a reduced compliance and a hyperdynamic condition.

Aged↗

Calcium-dependent intestinal chloride secretion by Vibrio parahaemolyticus thermostable direct hemolysin in a rabbit model.

BACKGROUND & AIMS: Vibrio parahaemolyticus is a major agent of seafood gastroenteritis that induces intestinal secretion in the rabbit through its thermostable direct hemolysin. The aim of this study was to characterize the enterotoxicity of purified hemolysin in vitro. METHODS: Rabbit ileum was mounted in Ussing chambers, and changes in potential difference and short-circuit current were monitored after addition of hemolysin. Intracellular calcium concentrations in the nontumoral rat crypt-derived cell line IEC-6 were measured using microspectrofluorometry. RESULTS: In Ussing chamber experiments, mucosal toxin addition up to 50 hemolytic units per milliliter induced a proportional increase of the electrical parameters in normal but not Cl(-)-free Ringer's solution. The response to the toxin was not additive to that of calcium ionophore A23187 and was eliminated by preloading the tissue with 1-2-bis(o-aminophenoxy)ethane N,N,N',N'-tetraacetic acid (BAPTA), a calcium buffer. In IEC-6 cells, a 10-fold increase in intracellular calcium level was found after addition of hemolysin. Such an increase was totally quenched by BAPTA. Finally, preincubation with trisialoganglioside GT1b, but not monosialoganglioside GM1, eliminated toxin-induced increases in potential difference and short-circuit current. CONCLUSIONS: These data support the hypothesis that the thermostable direct hemolysin induces intestinal chloride secretion using GT1b as a putative receptor and Ca2+ as a second messenger.

Animals↗

Treatment of acute renal failure in intensive care patients by continuous arteriovenous hemofiltration (CAVH): two years' experience in two centres.

The study objective was to evaluate the outcome of continuous arteriovenous hemofiltration (CAVH) as a first choice treatment for acute renal failure (ARF) in critically ill intensive care patients in two centres with a long experience in the field of continuous renal replacement therapies. Sixty consecutive intensive-care ARF patients from Uppsala Centre and 71 consecutive ARF patients from Vicenza Centre were included during a period of two years. Their age range was 58 +/- 16 and 52 +/- 15 years in Uppsala and Vicenza, respectively. CAVH was performed in the postdilution form using different types of hemofilters. Three choices of vascular access were utilised in each centre, namely: the Buselmeier shunt, femoral vessel catheter and the Scribner shunt. The pre-treatment serum urea level (mean +/- SD) in the Uppsala patients (30 +/- 14 mmol/l) was significantly higher (p < 0.001) than that of the Vicenza patients (17 +/- 10 mmol/l). The Uppsala patients had a longer treatment duration than the Vicenza patients; 8 +/- 6 vs 5 +/- 5 days (p < 0.05) perhaps because they were much older than the Vicenza patients (p < 0.05) in addition to their multi-organ failure. However, the total outcome of CAVH in the two centers was not significantly different (52 and 58% patient's survival in Uppsala and Vicenza, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Kidney Injury↗

Whole lung lavage.

Bronchoalveolar lavage is universally employed as a diagnostic procedure and also, both in the massive (whole lung) and limited forms, has important therapeutic applications. Since the second half of the century whole lung lavage (WLL) has been applied in patients with pulmonary alveolar proteinosis and has proved successful. The procedure has improved over the years in terms of safety and efficacy, whilst indications and methods for WLL are not yet completely defined and standardized. In this paper, we summarize the history of the development of WLL, and describe the procedure used eight times in five patients in our department.

Adult↗

Effects of deconjugated bile acids on electrolyte and nutrient transport in the rabbit small intestine in vitro.

To obtain new information on the poorly investigated mechanisms of the diarrheogenic effects of bile acids, we investigated the effects of the unconjugated bile acids chenodeoxycholate and ursodeoxycholate on the small intestine transport of electrolytes and nutrients in the rabbit jejunal and ileal mucosa mounted in vitro in Ussing or influx chambers. When added to the ileal mucosa at a concentration of 1 mM, both bile acids induced a secretory shift in ion transport; absorption of Na and Cl was abolished and secretion of bicarbonate was enhanced. No changes in short circuit current or electrolyte transport were observed when the bile acids were added to the jejunal mucosa. The addition of 1 mM chenodeoxycholate to the luminal side of the ileum induced a marked inhibition in the uptake of glucose, phenylalanine, and glutamic acid. A similar inhibition, though of a lesser magnitude, was also induced by both bile acids on jejunal nutrient transport. Further studies on the inhibitory effect of chenodeoxycholate on glucose influx showed that the inhibition was dose-dependent; at 1 mM it was maximal and resulted in the complete abolition of the active component, with only the diffusional pathway still operative. We conclude that unconjugated bile acids act as secretagogues in the ileum and significantly blunt the active transport of nutrients in the small intestine. Both effects may well play a role in the diarrheogenic action of these bile acids.

Animal Nutritional Physiological Phenomena↗

Efficacy and safety evaluation of lacidipine compared with amlodipine in mild-to-moderate hypertensive patients.

Hypertension is well recognized to be an important cardiovascular risk factor and antihypertensive therapy has been shown to decrease cardiovascular mortality and morbidity as blood pressure control is achieved. At present, management of hypertension is obtained with effective compounds that exhibit a satisfactory safety profile. Among the antihypertensive drugs, calcium antagonists have been proven to possess this property. In the present study, our objective was to compare the antihypertensive effect of two new long-acting dihydropyridines, lacidipine and amlodipine, as once-daily monotherapies in mild-to-moderate hypertensive patients. Eighty hypertensive patients were recruited and after a 3-week washout period were randomized to receive lacidipine 4 mg once daily or amlodipine 10 mg once daily. After 4 weeks, hydrochlorothiazide 12.5 mg was added in patients not adequately controlled, and patients were treated for a total of 8 weeks. At this time, supine mean diastolic blood pressure decrease was 16 mm Hg in the lacidipine group and 10 mm Hg in the amlodipine group (p < = 0.01). Adverse events were reported in 28% of patients treated with lacidipine and in 48% of patients receiving amlodipine. Results of our pilot clinical experience show that lacidipine is a well-tolerated and effective compound, compared with amlodipine, in mild-to-moderate hypertensive patients.

Adult↗

Liposomal amphotericin B (AmBisome) in Mediterranean visceral leishmaniasis: a multi-centre trial.

Thirty-one patients with visceral leishmaniasis (VL) caused by Leishmania infantum received liposomal amphotericin B (AmBisome) in a multi-centre study. Ten immunocompetent patients (six children) received 1-1.38 mg/kg/day for 21 days, and ten (nine children) received 3 mg/kg/day for 10 days. All were cured without significant adverse events and without relapse during 12-24 months of follow-up. Eleven immunocompromised adults, including seven co-infected with HIV (four with AIDS) received 100 mg (1.38-1.85 mg/kg) daily for 21 days. All were initially considered cured, but eight relapsed clinically and parasitologically at 3-22 months. Liposomal amphotericin B is a new, safe and effective drug for the treatment of VL.

AIDS-Related Opportunistic Infections↗

Comparative effects of atrial natriuretic peptide and E. coli heat-stable toxin on rat intestinal transport.

Conflicting data have been published in favor of or against a secretory effect of atrial natriuretic peptide (ANP) in the intestine. The reported effects resemble that of Escherichia coli heat-stable enterotoxin (ST). In this work the effects of ANP were studied in well established experimental systems and compared with that of ST. Both peptides induced a prompt secretion of water, Na, and Cl with no effects on K net transport in the in vivo rat perfused jejunum. The addition of ST, but not of ANP, evoked an increase of short circuit current in rat intestinal mucosa mounted in Ussing chambers. ST induced a significant increase in guanylate cyclase activity in intestinal homogenates, whereas ANP showed no effect. No binding sites for ANP were detected in basolateral or brush border membranes, nor in isolated enterocytes by a suction filtration technique. In conclusion, ANP acts as a short-lived intestinal secretagogue in the rat. Its mechanism of action is different from that of E. coli ST and appears to be indirect, since is not mediated by specific intestinal receptors and is not evident in vitro.

Animals↗

Louis-Bar syndrome: spontaneous and induced chromosomal aberrations in lymphocytes and micronuclei in lymphocytes, oral mucosa and hair root cells.

Louis-Bar (L-B) syndrome, also called ataxia-telangiectasia, is cytogenetically characterized by an increased frequency of spontaneous and induced chromosomal aberrations (CA) in cultured lymphocytes and skin fibroblasts. However, it is not yet clear whether the chromosomal instability is also present in uncultured cells. The spontaneous and bleomycin-induced CA in peripheral lymphocytes of 8 L-B patients were evaluated. The micronucleus test was also performed, for the first time in lymphocytes by the cytokinesis-block method, and in uncultured cells of the oral cavity and hair root. The spontaneous frequency of CA and micronuclei in lymphocytes was about 3 times higher in L-B patients than in controls, these two cytogenetic parameters being highly correlated. Moreover, the induction by bleomycin of CA was higher in patients than in controls. The micronuclei in buccal and hair root cells of patients were normal. It remains to be determined whether the different responses obtained with cultured and uncultured cells are the result of the different L-B gene expression of chromosomal instability or whether they arise because of a particular cell sensitivity to culture conditions. The spontaneous and induced CA in lymphocytes of heterozygotes cultured in the presence of L-B serum were studied to evaluate a possible increased sensitivity of heterozygotes to a possible diffusible clastogenic factor present in the plasma of L-B patients. We could not demonstrate the presence of any factor that enhances CA in normal subjects or in heterozygote carriers.

Adolescent↗

Evaluation of chromosomal aberrations in lymphocytes and micronuclei in lymphocytes, oral mucosa and hair root cells of patients under antiblastic therapy.

In 7 patients undergoing antiblastic chemotherapy for the first time, the structural chromosomal aberration (CA) test in peripheral lymphocytes was compared with the micronucleus (Mn) test in lymphocytes, in oral cavity cells and in hair root cells of the scalp. The last test is being proposed for the first time. The CA and Mn frequencies induced by chemotherapy were compared with the baseline (pretreatment) frequencies of the patients and with confidence limits calculated in 4 control groups studied for CA, Mn in lymphocytes, Mn in oral cavity cells and Mn in hair root cells, respectively. The studied chemotherapies induced a clear cytogenetic effect in at least 2 of the tests studied with the exception of interferon-alpha 2b (patient 6) and interferon + low doses of cis-platinum (patient 2) which did not appear to cause evident chromosomal damage. The response to chemotherapy is generally characterized by an increase in Ca and Mn, reaching a peak value and then decreasing in the following weeks. The CA test proves to be the most sensitive despite the fact that CA were analyzed in an average of 100 cells per sample against the 500-3000 cells analyzed for Mn. The efficiency of Mn to detect CA is in the following order: Mn in lymphocytes greater than Mn in buccal cells greater than Mn in hair root cells. The last test appears to be very promising but, used following the current method, does not appear suitable to monitor acute exposure.

Adult↗