PubMed Health⌕ Search

Biomedical subjects

M Valenti

Publications and source records attributed to M Valenti.

At least 127 records · Page 7Linked to original sources

Bioavailability of intranasal neostigmine: comparison with intravenous route.

The pharmacokinetics of intranasal (i.n.) neostigmine was compared with the intravenous (i.v.) route in 6 healthy volunteers with a mean age of 25.5 years and a mean weight of 65.8 kg in a crossover design. The doses used were 0.5 mg i.v. and 21.6 mg i.n. Neostigmine was determined by HPLC. The plasmatic profiles of the two routes were similar. An early peak of plasmatic concentration after i.n. administration was observed. The absolute bioequivalence of the i.n. route was ten-fold greater than the oral one.

Administration, Intranasal↗

Antiulcer activity of some PG-like derivatives and their intermediates.

During a search on PG-like compounds as antiulcer drugs we synthetized some hetherocyclic derivatives. Some compounds of this series were found to be effective after oral administration in inhibiting restraint induced ulcers in the rat. Three of the most active compounds showed fairly good antiinflammatory activity in the carrageenin-induced rat paw oedema test and in the RPAR test.

Animals↗

Is there an abnormal fasting duodenogastric reflux in nonulcer dyspepsia?

A quantitatively and/or qualitatively abnormal duodenogastric reflux (DGR) could be involved in the pathogenesis of nonulcer dyspepsia (NUD). The aims of this prospective study were to look for (1) a pathological DGR profile during fasting and (2) an eventual correlation between DGR profile and clinical symptoms. Twenty-six NUD patients were investigated. Seven other operated patients with a surgical procedure facilitating DGR episodes and 27 healthy volunteers served as control groups. A clinical score was determined for each patient from a standardized questionnaire. Gastric aspiration was performed for 6 hr in fasting subjects. The aspirates were pooled into 17 samples. In each sample the concentration and the output of total bile acids was determined. If the concentration was larger than 30 mumol/liter in pooled samples, the concentrations of free bile acids and the distribution of the conjugated bile acids was determined. The percentage of aliquots with a total bile acid concentration larger than 50 mumol/liter (without upper limit), and the percentage with a concentration larger than 2500 mumol/liter was also obtained. No significant difference was demonstrated between the healthy volunteers and NUD patients, whatever the parameter considered. However, there was a significant increase in each of the quantitative parameters for the group of operated patients in comparison with the NUD patient group. No significant correlation was found between the clinical score and the DGR profile in NUD patients. Apparently, DGR episodes do not play a primary role in the pathogenesis of NUD.

Adult↗

Prostaglandins intermediates. Reduction of (E)-oxolactone by means of a chiral phase transfer catalyst.

Preparation of (15 S)-hydroxy derivative (1-b), a key intermediate in the synthesis of PG like compounds, by reduction the corresponding enone (2), is described. High yields in (S)-isomer was obtained by means of chiral phase-transfer catalyst: (-)-N-(1-dodecyl)-N-methylephedrinium bromide. Eleven ammonium quaternary salts derived from (-)-N-methylephedrine were prepared and tested as catalyst in the reduction of enone (2) with NaBH4. Synthesis of enone (2), from phosphonate (6) (via Wadsworth-Emmons reaction) is also described.

Biphenyl Compounds↗

The pharmacokinetics of clotiazepam after oral and sublingual administration to volunteers.

We have studied the single dose pharmacokinetics of 5 mg clotiazepam drops, oral tablets, and sublingual tablets in a cross-over study in 6 healthy volunteers (median age 28 years). The formulations had similar systemic availability. Compared with oral tablets the sublingual route gave a lower peak concentration and a delayed peak time, while drops gave a greater maximum concentration with a similar peak time. The use of drops is suggested for a more marked initial effect and the sublingual route for easier administration, especially in the elderly.

Administration, Oral↗

Single-dose pharmacokinetics of flurbiprofen granules and tablets in healthy volunteers.

The bioavailability of granules and tablet flurbiprofen in 100 mg single dose was crossover compared in 6 healthy volunteers (mean aged 26.8 years). The granules showed an earlier peaktime and a lower maximum concentration than the tablet. Area under the curve and half-time in terminal phase were similar, with the granule relative bioavailability of 0.98.

Adult↗

[Humoral markers of iron status in patients on maintenance hemodialysis].

In forty-nine patients on regular dialysis treatment (RDT) we evaluated following parameters for a period of twenty-four months: serum ferritin (SF), transferrin, T.I.B.C. percental saturation (Fe/TIBC%), haemoglobin (Hb). Twenty-five patients had received more than 5 g intra-venous iron or several blood transfusions, before the beginning of the study, while the other twenty four patients had never received iron treatment nor transfusions. Serum ferritin and Fe/TIBC% proved to be a good estimate of iron stores in RDT patients. In fact both parameters showed significantly higher levels in iron loaded patients than in never treated patients. Furthermore, in patients who no longer received iron loads during the study period, both SF and Fe/TIBC% showed a significant decrease, without changes in haematologic values. This study demonstrated that oral ferritinic iron (40 mg/day for 6 months) doesn't increase either SF and Fe/TIBC% levels, or modifies haematologic values.

Anemia, Hypochromic↗

[Acute renal insufficiency caused by diflunisal. Description of a case].

A case of kidney failure in a patient with cirrhosis of the liver in the ascitic stage after treatment of a non-steroid anti-inflammatory drug, diflunisal, is reported. The pathogenesis of the kidney impairment, quickly reversed by withdrawal of the drug, is attributed to pharmacological inhibition of cyclo-oxygenase and prostaglandin synthesis with consequent alterations of intrarenal haemodynamics and renal blood flow.

Acute Kidney Injury↗

[Effects of long-term treatment with L-carnitine on dyslipemia in hemodialysis patients].

The effect of long-term intravenous administration of L-carnitine on the lipid pattern of 18 patients on intermittent haemodialysis has been evaluated. Serum levels of carnitine were assayed at the beginning and after 4 months of treatment: no significant change was observed. At the end of our investigation, we found a significant reduction of HDL-cholesterol and a significant increase of triglyceride levels, compared with basal values. On the contrary cholesterol levels did not change. Five of the patients though behaved as responders to the treatment: their triglyceride levels decrease while their carnitine values rose significantly. The Authors discuss the therapeutic importance of L-carnitine and its possible influence on dyslipaemia of uremic haemodialysed patients.

Carnitine↗

Correlation between the direct IgG MAR test (mixed antiglobulin reaction test) and seminal analysis in men from infertile couples.

The direct IgG mixed antiglobulin reaction (IgG MAR) test was carried out in 395 male subjects from infertile couples, selected on the basis of their seminal characteristics (sperm concentration greater than 10 X 10(6)/ml, sperm motility greater than 10%); attempts were made to correlate results with the seminologic aspects of the ejaculate. A significant correlation was observed between a positive MAR test and spontaneous sperm autogglutination. No correlation was observed, however, between test positivity and concentration, motility and sperm morphologic features, the macroscopic aspects studied (viscosity, fluidification), or increased concentration of leukocytes.

Female↗

[Nephrotoxicity of contrast media for urography in patients with chronic renal insufficiency].

The incidence of nephrotoxicity caused by intravenous pielography (IVP) contrast media was retrospectively evaluated in 42 patients with chronic renal failure. In 14 patients renal function was acutely impaired after IVP. In most cases the dysfunction was only temporary; in 3 cases permanent damage was induced, one of which required dialytic treatment. In the cases described there appears to be no correlation between the degree of renal failure and the incidence of nephrotoxicity but the former is clearly linked to the severity of the nephrotoxic response.

Contrast Media↗

[Surgical treatment through embolectomy of embolism of the superior mesenteric artery (author's transl)].

The Authors present four cases of embolism of the superior mesenteric artery treated surgically, with satisfactory results, through embolectomy with Fogarty's catheter. The Authors affirm the necessity of always following this type of intervention, given its simplicity and the high rate of mortality of non treated embolism. Some anatomical and physio-pathological considerations are remembered and diagnostic and surgical promptness are recommended.

Adult↗

Response bias in category and magnitude estimation of difference and similarity for loudness and pitch.

Interval scales of sensory magnitude were derived from magnitude and category estimates of loudness differences, loudness similarities, pitch differences, and pitch similarities. In each of the four loudness experiments, a loudness scale was constructed from a nonmetric analysis of the rank order of the judgments. The four loudness scales so constructed were found to be equivalent to one another and indicated that loudness was a power function of sound pressure with an exponent of .29. A similar analysis for the four pitch experiments found the pitch scales derived in each case to be equivalent to one another and linear with the mel scale of pitch. Thus the same sensory and similarities for two distinct perceptual continua. For both pitch and loudness, these sensory scales were used to generate scales of sensory differences. A comparison of the category and magnitude estimates of sensory differences with the scale of sensory differences derived from the nonmetric analyses indicated the presence of significant response biases in both category and magnitude estimation procedures.

Acoustic Stimulation↗