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Biomedical subjects

F Rossi

Publications and source records attributed to F Rossi.

At least 865 records · Page 48Linked to original sources

Periaqueductal gray area and cardiovascular function.

The periaqueductal gray (PAG) area seems to play an important role in modulating several biological functions such as the triggering of stereotyped defence and reproductive behaviour, pain, anxiety and cardiovascular and respiratory activities. Anatomically this midbrain area is made up of symmetric neuronal columns arranged along the long axis of the aqueduct. In this paper we review the most important findings of the last 10-15 years about the interaction between the PAG area and the cardiovascular function. It is shown that these neuronal columns within the PAG area exhibit a viscerotropic organization which elicits both hypertensive and hypotensive responses. In particular, the stimulation of the ventral neuronal column evokes a hypotensive response associated with a regional decrease in the vascular resistance. On the contrary, the stimulation of the dorsal and lateral neuronal columns evokes arterial hypertension associated with specific changes of the vascular resistance. Recently the authors demonstrated that the glutamergic system in the PAG area (prevalently through NMDA subtype receptor) may also be involved in the control of cardiovascular system. Moreover, the involvement of the arginine vasopressin neuropeptide in the hypertension induced by administration of excitatory amino acids into the PAG area has been demonstrated.

Animals↗

Synthesis and anti-inflammatory activity of esters derived from 5-aryl-1,2-dihydro-2-(2-hydroxyethyl)-3H-1,2,4-triazole-3-thiones.

Some aliphatic and aromatic esters 2a-l were prepared starting from 5-aryl-1,2,4-triazoline-3-thiones bearing a 2-hydroxyethyl chain in position 2. The title compounds were evaluated for antipyretic and anti-inflammatory activities. Nearly all derivatives and in particular 2f, 2h, 2k exhibited antiphlogistic properties but were lacking in antipyretic activity.

Analgesics, Non-Narcotic↗

A novel aspect of lindane testicular toxicity: in vitro effects on peritubular myoid cells.

The in vitro effects of the insecticide lindane have been investigated in rat testis peritubular myoid cells (PMCs). Upon PMC exposure to lindane, polarity increase and decrease of dipole dynamics were seen at the membrane level (EC50 20 microM), leading to a partial dissipation of the membrane intrinsic dipole potential. The initial membrane depolarization was increased by Cl- efflux and limited by Ca(2+)-activated repolarizing currents. Concomitantly, lindane produced an increase in [Ca2+]i (EC50 125 microM) resulting from both Ca2+ release from an inositol 1,4,5-trisphosphate-sensitive intracellular store and a voltage-dependent Ca2+ influx from the extracellular medium. Of particular interest from a toxicologic point of view, insecticide concentrations well below those effective in altering ion homeostasis potently inhibited both [Ca2+]i increase and contraction induced by the natural agonists vasopressin and endothelin-1 (IC50s < 10 microM). These data demonstrate that PMCs are highly susceptible to lindane and suggest that the insecticide may exert testicular toxicity by interfering with hormone-regulated PMC function.

Animals↗

Radical radiotherapy of localised prostate cancer: the relationship between radiation dose and survival.

PURPOSE: This retrospective study aims to define the effects of different radiation dose levels on survival, local control and toxicity in a series of 208 patients with localised prostate cancer consecutively treated with radical radiation therapy. PATIENTS AND METHODS: From 1982 through 1996, 365 patients with prostate cancer have been consecutively treated with radical radiotherapy in Florence (n = 306) and Arezzo (n = 59). The 208 cases treated until January 1994 with Stage B (125/208, 60%) and C (83/208, 40%) are the objects of the present study. The treatment was most often limited to the prostatic area (81%), using a four-field "box technique" and 25 MV photon beams, up to a total dose of 60-65 Gy (21% of the patients), of 66-69 Gy (26%) and of 70 Gy (53%); conventional fractionation was used (fractional dose: 2 Gy; five fractions/week). Hormonal therapy was also given to 39% of the cases. The possible relationship between dose, stage, grading and survival has been analysed. The survival figures and the types of relapse observed (prostatic, lymphnodal or "biochemical") have been analysed also according to the extent of the target volume and to the prostate-specific antigen (PSA) value at diagnosis, in the entire series or in selected subgroups. RESULTS: In the whole series and also after radiation alone, the patients with Stage B, with more differentiated tumours and those treated with higher doses to the prostate obtained significantly better survival results. Multivariate analysis confirmed that the dose level has an independent prognostic value. The use of a limited target volume did not produce an excess of pelvic lymphnodal failures. Among the patients more recently treated with radiation alone, the PSA level at diagnosis is strongly related with the risk of local and "biochemical" failure, and also with the relapse-free survival. Toxicity was acceptable, also for the patients treated with higher doses, but late treatment-related damage is more frequent in patients treated on larger volumes. CONCLUSION: The results of this retrospective analysis confirm the good results of small volume, high dose radiation therapy of prostatic cancer, even taking into account the possible biases due to the retrospective nature of the study, and the relevance of the PSA level at diagnosis to define the risk of local failure.

Adenocarcinoma↗

Comparison of the conventional 'box technique' with two different 'conformal' beam arrangements for prostate cancer treatment.

PURPOSE: To quantify the possible advantages arising from the use of 'conformal' radiotherapy of localized prostate cancer, and to compare the dose distributions obtained with two different 'conformal' techniques. PATIENTS AND METHODS: Twelve patients with localized prostate cancer were enrolled in the study. For each patient, three techniques were planned: the standard 'box technique' (A), a four-fields 'conformal' technique (B), and a 6-fields conformal technique (C). For each of the 36 3D plans, dose-volume histograms (DVH) were obtained, along with the mean, maximum and minimum doses for the clinical and planning target volumes (CTV, PTV) for the rectum, the bladder, and the femoral heads. The resulting data were compared. RESULTS: On average, the standard technique resulted in the exposure of a significantly larger bladder volume to the higher doses; a similar, but less remarkable difference has been observed for the rectal volume. The coverage of the PTV appears to be significantly more homogeneous with the two conformal techniques. CONCLUSIONS: The results presented here add to the evidence available in the literature and suggest a possible advantage of both the conformal techniques over the standard 'box technique' for the treatment of localized prostate cancer. The 6-field conformal technique does not seem superior to the four field one.

Aged↗

[Cost of psychiatric patients by disability type].

OBJECTIVE: The study of the relation between treatment costs and disability of psychiatric patient groups. DESIGN: Perspective assessment of costs and disability of 1371 adult psychiatric patients in charge at two Operative Psychiatric Units (OPU), followed during an average period of 9 months. Data are related to all OPU's psychiatric services, including ambulatory, full or half-residential and psychiatric departments of acute hospital services. SETTING: OPUs of Magenta (MI) and Desio (MI). METHOD: The disability level has been measured by Health of the Nation Outcome Scales (HoNOS) filled in at the inclusion of the patient in the study and every three-months on average thereafter. Besides other HoNOSs have been filled in both at admission and discharge from psychiatric departments of acute hospitals, Residential Centres of psychiatric Therapies and Rehabilitation and Guarded Communities. All patients have been grouped using the main psychiatric diagnosis (first digit ICD-10) and the maximum disability level shown in the whole period of the study. Direct costs of publicly financed psychiatric services have only been considered. Their attribution to each patient has been made applying standard costs or tariffs (diagnostic procedures) to the data perspectively collected by the regional Register and a purposely designed protocol. RESULTS: Total cost of 1371 patients has been 9771.1 million lire with a cost per patient of 7,127,000 lire (sd 19,499,000) and a cost per "day in charge" of 27,172 lire (sd 68,358). The cost per day has been found unrelated with the length of observed time frame. At the inclusion the mean level of disability has been 4.26 points (sd 3.73) and 3.19 points (sd 3.26) at the end of the study. Its value, measured at maximum level shown by each problem in the whole period of study, has been 6.00 points (sd 4.64). Disability and treatment cost of each patient did result directly related (r = 0.626, p = 0.0001). All patients have been grouped in 12 classes with a significant (p = 0.0001) overall difference on both their disability level and treatment cost. CONCLUSIONS: All adult psychiatric patients could be grouped in disability related classes which sometimes have also a different treatment cost. A study on a greater number of patients is needed to confirm these results. It may also provide a more reliable basis for a new financing system of psychiatric services.

Adult↗

Testicular peritubular myoid cells are a target for adrenomedullin.

Adrenomedullin (AM) is a recently cloned vasorelaxing peptide that belongs to the calcitonin gene-related peptide family. AM inhibits the contraction of several types of smooth muscle cells and is present in the testis as well as in many other organs. The authors investigated whether testicular peritubular myoid cells (PMC) possess specific receptors for AM. Binding of AM to PMC was saturable in a time-dependent manner and 125I-AM binding was effectively displaced by cold AM. The study documents that testicular peritubular myoid cells are a target for adrenomedullin and suggests a role for this peptide in the paracrine regulation of the testis.

Adrenomedullin↗

Effect of ethanol exposure on Xenopus embryo lipid composition.

Exposure to ethanol is known to alter cell membranes both chemically and biophysically; these effects may be related to the development of tolerance and physical dependence. In the present study, the effects of various concentrations of ethanol (1-250 mM) on the lipid composition after the first 6 days of Xenopus embryo development were investigated, using an in vitro fertilization technique. Lipid analysis revealed: (1) a decrease of the cholesterol/phospholipid molar ratio mainly derived from a higher content of phospholipids; (2) an increase of phospholipid unsaturated fatty acids, especially C20:4 and C20:5, with ethanol concentration of 150-250 mM; (3) a decrease of lipid-bound sialic acid with ethanol concentrations of > or =5 mM. These results underline that sialoglycoconjugates are a more sensitive target of alcohol in comparison with other lipid components. The cultured embryo method certainly represents a useful model for investigation of the direct effects of ethanol on lipid metabolism, excluding maternal interference which can lead to misinterpretation of data.

Animals↗

Cardiopulmonary bypass through peripheral cannulation with percutaneous decompression of the left heart in a model of severe myocardial failure.

Prolonged closed chest cardiopulmonary bypass for severe total biventricular myocardial dysfunction requires invasive decompression of the left heart. The authors have developed an elongated helical coil that is permanently attached to the distal 8-10 cm of a flow directed Swan-Ganz catheter. When properly positioned, the helical coil kept the pulmonary artery (PA) and the tricuspid valves open, and allowed closed chest retrograde decompression of the left heart. The authors have evaluated the merits of closed chest cardiopulmonary bypass with decompression of the left heart in this manner in four sheep subjected to 30 min of warm global myocardial ischemia, along with induced ventricular fibrillation. All sheep developed severe global myocardial failure, with no left ventricular (LV) ejection. The authors have shown that pulmonary blood flow during cardiopulmonary bypass was reversed from the left heart, across the lungs, and into the right heart. The wedge pressure never exceeded 12 mmHg at any time, attesting to good decompression during periods of total ventricular failure, during partial recovery with some LV ejection, and after good recovery of LV function, followed by weaning from bypass after 44, 67, and 78 h of such support. One sheep could not be weaned from bypass, even after 5 days of CPBP. Lung function in all sheep remained unimpaired throughout, and there was no wound bleeding. The authors conclude that in this model of total myocardial failure, and while on closed chest CPBP, at all times and with all degrees of myocardial dysfunction, excellent LV decompression with the helical coil catheter was attained.

Animals↗

Spinal subarachnoid cyst in a cat.

A 7-year-old neutered female domestic short hair cat was presented with hind limb ataxia. A subarachnoid cyst in the T10-T11 spinal cord region was identified by myelography as a collection of contrast medium in the subarachnoid space.

Animals↗

Magnetic resonance imaging of articular process joint geometry and intervertebral disk degeneration in the caudal lumbar spine (L5-S1) of dogs with clinical signs of cauda equina compression.

The geometry of the lumbosacral region has been suspected to play a role in the development of degenerative lumbosacral stenosis in the dog. In this study, 50 dogs (21 German Shepherd dogs and 29 dogs of other breeds) with clinical signs of cauda equina compression were studied by magnetic resonance (MR) imaging. The orientation of the articular process joints in the L5-S1 region and the angle difference between two adjacent motion segments were calculated. Intervertebral disc degeneration of the same region was identified and classified in four stages. A positive association between MR-imaging stage and articular process joint angle difference in the transverse plane was found in the two groups of animals. German Shepherd dogs and dogs of other breeds had different geometry of the lumbosacral region with different articular process joint angles in the transverse plane and statistically different stages of disc degeneration.

Animals↗

Pharmacokinetics of cefodizime in patients with various degrees of renal failure.

The pharmacokinetics of cefodizime, a new expanded-spectrum cephalosporin for parenteral use, was studied in 45 subjects with various degrees of renal failure. Patients were divided into five groups according to the following creatinine clearances: group I >80 ml/min; group II <80-30 ml/min; group III <30-15 ml/min; group IV <15-5 ml/min and group V <5 ml/min. Cefodizime was administered as a 1 g i.v. bolus. Plasma and urinary concentrations of cefodizime were determined by high-performance liquid chromatography, using for detection UV absorbance. The following pharmacokinetic parameters were calculated: maximum plasma concentration (C5 min), area under the plasma concentration-time curve (AUC), terminal half-life (T1/2), terminal rate constant (lambda-z), total clearance (Clt), volume of distribution (Vd), mean residence time (MRT), urine data-derived terminal half-life (T1/2 r), renal clearance (Clr). The results of this study showed that renal failure induced changes in cefodizime pharmacokinetics. Our data demonstrated a close correlation between degree of renal impairment and pharmacokinetic changes. The maximum plasma concentration (C5 min) was higher in patients with renal failure; T1/2 was increased; AUC also increased from 470.40 +/- 17.80 mg.h/l in the control group to 1,562.30 +/- 170.8 mg.h/l in group V. Moreover, no side effect was observed after treatment with 1 g i.v. of cefodizime. Although renal failure induces significant changes of cefodizime pharmacokinetics, the drug was well tolerated and only in patients with severe renal insufficiency we advise to monitor the interval dose of cefodizime or adjust doses to renal function.

Adolescent↗

Gene expression and morphological changes in surgically injured carotids of spontaneously hypertensive rats.

The expression profiles of genes involved in cell proliferation, differentiation and programmed death were investigated in carotids of spontaneously hypertensive rats (SHR) treated with a model of surgical injury that mimics events occurring during arterial grafts, endarterectomy and organ transplantation. The mRNA level of the c-myc, angiotensin II receptor 1 (AT1), Rb/p105, Rb2/p130, Bcl-2 and Bax-alpha genes was assessed by a semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) technique at different times up to 48 h after injury, while the morphological changes were evaluated 30 days after injury. The proliferation marker c-myc increases almost immediately, peaks after 4 h and returns to basal levels after 24 h; the AT1 receptor mRNA reaches its maximal level 48 h after injury. The level of cell cycle exit markers Rb/p105 and Rb2/p130 gradually decreases after injury. The apoptosis marker Bcl-2/Bax-alpha ratio shows a significant reduction only 4 h after injury, resuming the initial value after 24 and 48 h. Morphological analysis reveals that surgical injury in SHR induces adventitial and medial constrictive remodeling changes rather than intima proliferation as in balloon angioplasty. Both molecular and histological data show substantial differences with respect to normotensive rats.

Animals↗

Plasma cortisol and testosterone in hypercholesterolaemia treated with clofibrate and lovastatin.

Plasma testosterone and cortisol concentrations were measured in 32 familial heterozygous hypercholesterolaemic subjects, aged 40-45 years. The subjects were divided into two groups of 16, each containing eight men and eight women. The women had normal menstrual cycles. After a period on placebo, one group of patients was given 40 mg/day lovastatin and the other was given 1500 mg/day clofibrate. Both drugs significantly reduced the plasma cholesterol concentration, however, unlike clofibrate, lovastatin did not decrease plasma levels of testosterone and cortisol. The response to stimulation by adrenocorticotrophic hormone of plasma cortisol and urinary 17-hydroxy levels was significantly reduced by treatment with clofibrate, but unchanged by lovastatin. The different effects produced by the two drugs probably reflect different mechanisms and sites of action.

Adult↗

Effect of atenolol and ramipril on regression of left ventricular hypertrophy: comparative echocardiographic assessment.

Left ventricular hypertrophy (LVH) dramatically worsens hypertensive illness. Because the genesis of LVH appears to be multifactorial, antihypertensive treatment should aim to reduce not only pressor values but also the hypertrophic ventricular mass. This result can be obtained only when drugs able to act on both pathogenetic factors are used. To evaluate the effectiveness of antihypertensive therapy on regression of LVH, 21 patients with stage 2 essential hypertension were treated for a year with either atenolol (120 mg/d orally), a cardioselective beta-blocker without intrinsic sympathomimetic activity, or ramipril (5 mg/d orally), an angiotensin-converting enzyme inhibitor with high tissue activity. Both treatments produced significant control of hypertension and regression of LVH. No statistically significant difference between treatments was noted, except for heart rate, which was substantially unchanged by ramipril but significantly decreased by atenolol. Both drugs were well tolerated. Atenolol and ramipril have a major role in the long-term treatment of hypertension and in the regression of hypertension-associated LVH.

Aged↗