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Biomedical subjects

F Ferrari

Publications and source records attributed to F Ferrari.

At least 37 records · Page 2Linked to original sources
PubMed2002

Influence of sildenafil on copulatory behaviour in sluggish or normal ejaculator male rats: a central dopamine mediated effect?

The present study investigates the effects induced by sildenafil (1 mg/kg, p.o.) and the dopamine agonist, SND 919 (0.1 mg/kg, i.p.) on copulatory behaviour of male rats, categorized, on the basis of seven consecutive mating pre-tests, as sluggish and normal ejaculators (SE and NE, respectively). The data obtained show that sildenafil modifies both sexual arousal and ejaculatory mechanisms of copulation. It appears that, although it induced a facilitatory effect on ejaculation of all rats, similarly to SND 919, the lowering of ejaculatory threshold was achieved by means of a reduction of mount frequency and intromission frequency in SE and NE groups, respectively. Differently from SND 919, sildenafil increased sexual arousal, diminishing post ejaculatory interval in SE animals and inter-intromission interval in both SE and NE rats. As the dopamine antagonist, (-)eticlopride (0.02 mg/kg, s.c.), significantly inhibited sildenafil-induced enhancement of sexual arousal in SE rats, it is suggested that the drug acts both peripherally and centrally.

Animals↗
PubMed2002

Modulatory activity of sildenafil on copulatory behaviour of both intact and castrated male rats.

The first experiment of the present study investigates the effects induced by sildenafil (1 or 10 mg/kg po) on the copulatory behaviour of intact male rats, categorized, on the basis of seven consecutive mating pretests, as sluggish or normal ejaculators (SE or NE, respectively). The data obtained show that sildenafil modifies both sexual arousal and the ejaculatory mechanisms of copulation, diminishing ejaculation latency in both categories and increasing copulatory efficacy in SE rats; in addition, it reduced the inter-intromission interval in both SE and NE animals and the post-ejaculatory interval only in SE animals. The second experiment, conducted on rats 3 weeks after their castration, shows that sildenafil alone (1 or 10 mg/kg) did not modify copulatory failure. However, 3 months after castration, and 24 h after the last injection of testosterone (25 microg/kg sc) given twice weekly for 4 weeks, sildenafil (1 or 10 mg/kg) ameliorated rat copulatory performance.

Animals↗
PubMed2002

The early markers for later dyskinetic cerebral palsy are different from those for spastic cerebral palsy.

Qualitative abnormalities of spontaneous motor activity in newborns and young infants are early predictive markers for later spastic cerebral palsy. Aim of this research was to identify which motor patterns may be specific for later dyskinetic cerebral palsy. In a large, prospectively performed longitudinal study involving four European hospitals we identified twelve cases with the relatively rare condition of dyskinetic cerebral palsy and compared their early motor development with twelve spastic cerebral palsy cases and twelve controls. From birth to the fifth month post-term, all infants were repeatedly videoed and their spontaneous motor patterns, including general movements, were assessed. Until the second month post-term, the infants that later became dyskinetic displayed a poor repertoire of general movements, "arm movements in circles" and finger spreading. Abnormal arm and finger movements remained until at least five months and were then concurrent with a lack of arm and leg movements towards the midline. Later dyskinetic infants share with later spastic infants the absence of fidgety movements, a spontaneous movement pattern that is normally present from three to five months. Qualitative assessment of spontaneous motor patterns enabled us to identify infants at high risk for dyskinetic cerebral palsy early in life. Additionally, we were able to discriminate them from those infants at high risk for later spastic cerebral palsy. This is a matter of significant clinical relevance because the two types of cerebral palsy ask for different management and early intervention.

Biomarkers↗
PubMed2002

p53 mutation in breast cancer. Correlation with cell kinetics and cell of origin.

AIM: Several studies have investigated the expression of the cytokeratins (CKs), vimentin, the epithelial growth factor receptor (EGFR), the oestrogen receptor (ER), and the progesterone receptor (PgR), in breast cancer, but no study has directly compared p53 mutations with these phenotypic and differentiation markers in the same case. The present study was designed to provide some of this information. METHODS: The expression of the p53 and bcl-2 proteins was evaluated by immunohistochemistry in relation to phenotypic characteristics and cellular kinetic parameters (mitotic index and apoptotic index) in 37 cases of ductal carcinoma in situ (DCIS) and 27 cases of infiltrating ductal carcinoma (IDC) of the breast. In addition, p53 gene mutation was examined by polymerase chain reaction single strand conformation polymorphism analysis (SSCP). RESULTS: Thirteen cases (eight DCIS and five IDC) showed expression of CK8, CK14, CK18, vimentin, and EGFR, consistent with a stem cell phenotype, whereas 44 cases (27 DCIS and 17 IDC) showed expression of CK8 and CK1, weak or negative expression of CK18, but were negative for vimentin and EGFR, consistent with a luminal cell phenotype. DCIS and IDC cases with a stem cell phenotype were ER/PgR negative and intermediately or poorly differentiated. In contrast, the cases with luminal cell phenotype were ER/PgR positive and well or intermediately differentiated. In addition, intermediately or poorly differentiated cases with a stem cell phenotype showed higher proliferative activity (per cent of MIB-l positive cells) than did intermediately or well differentiated cases with a luminal cell phenotype. Both DCIS and IDC cases with a stem cell phenotype were p53 positive and bcl-2 negative by immunohistochemistry. In IDC, p53 expression was associated with a reduction of both mitotic index and apoptotic index compared with DCIS. Most of the tumours showing a more differentiated phenotype (luminal) were p53 negative and bcl-2 positive. In these cases, cell kinetic parameters increased from DCIS to IDC. These data suggest the existence of subsets of DCIS and IDC that, because of their phenotypic characteristics, could be derived from subpopulations of normal breast cells having different control mechanisms of cell proliferation and neoplastic progression. CONCLUSIONS: These results are compatible with the hypothesis that the phenotype of the cell of origin constrains both tumour phenotype and the choice of genetic events; however, the occurrence of p53 mutants by chance during neoplastic transformation cannot be excluded.

Adult↗
PubMed2002

High occurrence rate of glaucoma among patients with Alzheimer's disease.

The purpose of the current study was to reveal the occurrence rate of glaucoma among patients with Alzheimer's disease (AD). All 112 patients of four nursing homes in Upper Bavaria, Germany, who met the diagnostic criteria of probable AD, were incorporated into the study. Visual field defects and/or optic disc cupping compatible with the diagnosis of glaucoma were found in 29 out of 112 patients with AD (25.9%). When compared to a control group (5.2%) and to the prevalence of glaucoma in western countries revealed in a number of glaucoma surveys (2.6-4.7%), patients with AD may have a significantly increased occurrence rate of glaucoma. In addition, ocular hypertension with normal visual fields and normal optic nerve heads was not found in patients with AD. The prevalence of ocular hypertension in the control group was 7.8% and parallels previous surveys. Therefore, we assume that the optic nerve seems to be less resistant to elevated intraocular pressure levels in AD patients.

Aged↗
PubMed2002

[Integrated clinical record: unique document for diverse uses].

Technological and scientific development and changes in the health system have led to modifications and greater complexity in health documents and clinical records, without there being at the same time definition of guidelines on their correct compilation and formulation. The present study was designed to develop a single Integrated Clinical Record that combines, on the one hand, data of all medical, nursing and technical interventions and, on the other, involves the patient in all decisional processes of diagnosis and treatment during the hospitalization period. All phases of the project related to development of the Integrated Clinical Record are discussed. The data of 240 new clinical records regarding patients admitted consecutively over a period of 6 months are reported. The results show a progressive reduction of compilation errors and an improved management of the patient's clinical course. The innovative aspects of the new clinical record are discussed, with particular reference to the system of quality management, within which context the clinical record has to function, and to the modalities of check, audit and improvement.

Humans↗
PubMed2001

Complete atrioventricular block during renal transplantation in a patient with Alport's syndrome: case report.

CONTEXT: Patients with Alport's syndrome (causing 5% of end-stage renal disease) have a higher risk of heart conduction abnormalities. OBJECTIVE: To report a case of Alport's syndrome developing complete atrioventricular block during renal transplantation. CASE REPORT: A 21-year-old man with chronic renal failure due to Alport's syndrome was submitted to a renal transplantation under epidural anesthesia and, during the intraoperative period, a complete atrioventricular block was diagnosed and promptly treated with a transcutaneous pacemaker. This extensive sympathetic block can contribute towards disturbances in the heart conduction system, particularly in patients with chronic renal disease in hemodialysis. Even in patients with a normal preoperative electrocardiogram or no conduction system disturbances, some degree of atrioventricular block, including complete atrioventricular block, can occur. In this situation, a transcutaneous pacemaker provides rapid and effective treatment in the operating room, thereby permitting the planning of a definitive treatment.

Adult↗
PubMed2001

Characterization of chitosan hydrochloride--mucin rheological interaction: influence of polymer concentration and polymer:mucin weight ratio.

The aim of the present work was to investigate the influence of polymer concentration and polymer:mucin weight ratio on chitosan--mucin interaction, assessed by means of viscosimetric measurements. Two hydration media, distilled water and 0.1 M HCl, were used. Chitosan solutions were prepared at concentrations greater than the characteristic entanglement concentration and mixed with increasing amounts of porcine gastric mucin. Viscosity measurements were performed on the polymer--mucin mixtures and on polymer and mucin solutions having the same concentrations as in the mixtures. The flow curves were fitted according to a modified form of Cheng--Evans equation in order to obtain the relevant model parameters: low shear viscosity eta(0) and high shear viscosity eta(infinity), indexes of the sample structure at rest and upon high shear, respectively. The formation of chitosan--mucin interaction products was determined on the basis of the changes in eta(0) and eta(infinity) of the mixtures as a function of polymer:mucin weight ratio. Rheological synergism parameter was also calculated. The results obtained suggest that two different types of rheological interaction occur between chitosan and mucin in both media, depending on polymer concentration and polymer:mucin weight ratio: one is characterized by a minimum in viscosity and occurs at higher polymer:mucin weight ratio, the other one produces a positive rheological synergism and is observed in presence of an excess of mucin. Only the last one causes a 'strengthening' of the mucoadhesive interface and it is responsible for the mucoadhesive joint. This hypothesis is confirmed by tensile stress measurements performed on HCS solutions in presence of mucin dispersions at different concentrations.

Animals↗
PubMed2001

Synthesis and biosynthesis of isocordoin.

In the search of a convenient synthesis for isocordoin (1), a potential anticancer natural product, 2',4'-dihydroxychalcone was inoculated in cell suspension cultures of Morus nigra, which were expected to contain an active prenyltransferase. After 24 hours the target compound was easily isolated from the metabolite extract. Optimization of the biotransformation resulted in a 85% yield of the prenyl derivative.

Acetophenones↗
PubMed2001

Aromatic hydrocarbon degradation patterns and catechol 2,3-dioxygenase genes in microbial cultures from deep anoxic hypersaline lakes in the eastern Mediterranean sea.

Several mixed cultures able to grow on different aromatic hydrocarbons were obtained from different depths (between 3500 and 3660 m under the sea surface) of water/brine interfaces (1 to 5 m over the estimated brine surface) of three deep hypersaline anoxic basins (Urania, Discovery and Atalante) in the eastern Mediterranean sea. Eight strains which completely removed toluene from the medium in six to 10 days were isolated from one of the mixed cultures obtained from the Urania basin. The strains grew on toluene and yeast extract in the presence of NaCl concentrations of up to 50 and 100 g l(-1), respectively, indicating that they are halotolerant rather than halophilic. Even though DNA fingerprinting methods showed that the strains were strictly related, two groups could be found on the basis of the plasmid profile. Metabolic profiling and partial sequencing (350 bp) of the 16S rDNA showed that the strains were related to Pseudomonas mendocina. A 320 bp fragment of the catechol 2,3-dioxygenase gene from all the strains was aimplified by PCR. The sequence of the fragment showed 100% identity with xylE from pWW53 of Pseudomonas putida MT53 isolated from soil. Southern hybridisation experiments showed that catechol 2,3-dioxygenase is plasmid encoded.

Catechol 2,3-Dioxygenase↗
PubMed2001

Early intracardiac thrombosis in preterm infants and thrombolysis with recombinant tissue type plasminogen activator.

OBJECTIVES: To determine the incidence of catheter related thrombosis and to test the efficacy of recombinant tissue type plasminogen activator (rt-PA) in preterm infants. STUDY DESIGN: From January 1995 to December 1998, echocardiography was performed in the first few days of life in 76 very low birthweight (< or = 1500 g) infants out of a total of 147 having an umbilical catheter placed. When intracardiac thrombosis was diagnosed, rt-PA infusion was performed. RESULTS: Four infants (5%) developed an intracardiac thrombosis during the first few days of life. In three of them, rt-PA at a dose of 0.4-0.5 mg/kg in a 20-30 minute bolus led to dissolution of the clot. One patient received a three hour infusion after the bolus, at a dose of 0.1 mg/kg/h, with resolution of the thrombus. No systemic effects were observed after rt-PA infusion. CONCLUSIONS: Early thrombosis may occur as a complication of umbilical catheterisation in preterm infants; early echocardiographic detection of this disorder allows complete, safe, and rapid lysis with rt-PA.

Catheterization, Peripheral↗
PubMed2001

Role of vision on early motor development: lessons from the blind.

For a better understanding of the contribution vision makes to the development of other sensory systems and to movement and posture, we studied effects of early blindness by examining video recordings of 14 totally blind infants. Infants were born at term or preterm and showed no evidence of brain damage. During preterm and term periods no noticeable changes in motor activity were observed. Around 2 months postterm all infants showed clear delay in head control and abnormal, exaggerated type of 'fidgety movements'. Later, postural control was characterized by a prolonged period of ataxic features. Results indicate a lack of normal calibration exerted by vision on proprioceptive and vestibular systems. Early visuomotor coordination such as coordinated eye-head scanning and head orientating were present but disappeared after several weeks.

Blindness↗
PubMed2000

Factorial analysis of the influence of dissolution medium on drug release from carrageenan-diltiazem complexes.

This research studied the influence of buffer composition, pH, and ionic strength on the release of diltiazem hydrochloride from a complex of the drug with lambda carrageenan. Two viscosity grades of carrageenan were also compared. A factorial analysis was used to evaluate the influence of individual variables and their interactions. Both the complex solubility, measured as the drug concentration in equilibrium with the solid complex, and the drug release rate from constant surface area were considered. The increase of ionic strength significantly increased complex solubility in all the buffer systems. A significant effect of polymer grade on complex solubility was evidenced only in phosphate buffer with a pH of 6.8, indicating lower solubility of the complex when higher polymer molecular weight was involved. In most cases, drug release rate decreased when high polymer grade was involved in the complex. Ionic strength did not always have a significant effect on drug release rate and was quantitatively less important than for solubility. Ionic strength especially affected the drug release profiles. At higher ionic strength drug release was no longer constant, but decreased with time, probably because of lower polymer solubility.

Buffers↗
PubMed2000

Characterization of a diltiazem-lambda carrageenan complex.

In the present paper the interaction between lambda carrageenan, a natural sulphated polysaccharide, and diltiazem HCl, a Ca channel blocking agent, was studied. Dialysis equilibria were performed to quantify the binding capacity of lambda carrageenan for diltiazem. The relevance of the interaction to hydrophilic matrix systems was confirmed: a relationship was found between the binding capacity and the release profiles of matrix tablets containing a fixed amount of drug and different percentages of lambda carrageenan. Dialysis equilibria in buffered media showed that the interaction is quite insensitive to the pH of the medium (in the range 1.8-6.8), while it is reduced by increasing ionic strength; this behaviour is in line with the importance of ionic bonds in diltiazem-carrageenan interaction. On the basis of the calculated binding capacity, the complex was prepared, dried and milled. A preliminary characterization of the diltiazem-carrageenan complex in the solid state was effected by means of X-ray and DSC analysis. The amount of drug going into solution from the complex was not significantly affected by the pH of the medium (in the range 1.8-6.8), while it was increased by increasing ionic strength.

Calcium Channel Blockers↗
PubMed2000

Effects of the cannabinoid receptor agonist, HU 210, on ingestive behaviour and body weight of rats.

The effect of the synthetic cannabinoid receptor agonist, (-)11-hydroxy-Delta(8)-tetrahydrocannabinol-dymethylheptyl (HU 210), on rat body weight and eating and drinking behaviour was examined. In Experiment 1, the drug (25, 50 or 100 microg/kg), sub-chronically administered for 4 days, produced a dose- and time-dependent loss of body weight that, at the highest dose, was not regained by 7 days after the drug was stopped, and remained markedly below that of vehicle-treated animals. In Experiment 2, food and water intakes, which were evaluated in fasted rats, tested as in Experiment 1, were significantly inhibited only by the dose of 100 microgram/kg, and this effect was still present 7 days after the last injection of the drug. The possibility that the effects observed are not directly dependent on the control of appetite and might be ascribable to stress-related phenomena is discussed.

Animals↗
PubMed2000

The cannabinoid agonist HU 210 modifies rat behavioural responses to novelty and stress.

Experiments were performed on groups of rats after acute and sub-chronic treatment (once daily for 9 days) with the cannabinoid agonist HU 210 (25-100 microg kg(-1), i.p.) as well as 24 h and 7 days after the last drug injection. The animals underwent three behavioural tests in novel environments. In the observation cages (Test 1), rat locomotor activity was found to be dose-dependently reduced after acute and sub-chronic treatment at all doses and virtually unchanged during abstinence; grooming was potently inhibited by acute treatment but potentiated by the sub-chronic one at doses of 50 and 100 microg kg(-1), the effect of the higher dose persisting after 24 h and 7 days abstinence. Vocalization in animals in response to a tactile stimulus was highest after HU 210 at 100 microg kg(-1) in all experimental modes except after 7 days abstinence. In the X-maze (Test 2), sub-chronic HU 210 dose- dependently enhanced rat natural aversion for open arms, and this behaviour persisted during abstinence after the highest dose. Grooming in the X-maze was completely absent in rats acutely injected with HU 210 but potentiated in those sub-chronically treated or abstinent. In the swimming test (Test 3) rats sub-chronically treated at 50 and 100 pg kg(-1) displayed relevant wall-hugging and the same occurred 24 h after last injection. On the whole, our results are indicative of an anxiogenic-like effect of sub-chronic HU 210 at high doses and reflect the persistence of enhanced emotional response to novel environments when the treatment is discontinued.

Animals↗