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P Rossi

Publications and source records attributed to P Rossi.

At least 145 records · Page 8Linked to original sources
PubMed1999

Cross-sectional imaging in a case of adventitial cystic disease of the popliteal artery.

Adventitial cystic disease of the popliteal artery is an unusual condition of uncertain etiology, in which a mucin-containing cyst forms in the wall of the artery and produces lower extremity claudication, typically in young and middle-aged men. A diagnosis of adventitial cystic disease of the popliteal artery was made preoperatively in a 47-year-old man by means of several imaging modalities, including angiography, magnetic resonance imaging, and ultrasound. The pathological findings confirmed the suggested diagnosis.

Angiography↗
PubMed1999

Inhibition of poliovirus type 1 infection by iron-, manganese- and zinc-saturated lactoferrin.

In this study we investigated the inhibitory activity of different milk proteins on poliovirus infection in Vero cells. Proteins analyzed were mucin, alpha-lactalbumin, beta-lactoglobulin, and bovine and human lactoferrin. Viral cytopathic effect was not prevented by mucin, alpha-lactalbumin or beta-lactoglobulin, whereas the lactoferrins tested were able to inhibit the replication of poliovirus in a dose-dependent manner. Further experiments were carried out in which apo- and native lactoferrin or lactoferrin fully saturated with ferric, manganese or zinc ions were added to the cells during different phases of viral infection. Results obtained demonstrated that all lactoferrins were able to prevent viral replication when present during the entire cycle of poliovirus infection or during the viral adsorption step. Only zinc lactoferrin strongly inhibited viral infection when incubated with the cells after the viral attachment, being the inhibition directly correlated with the degree of zinc saturation. Our results demonstrated that all lactoferrins interfered with an early phase of poliovirus infection; zinc lactoferrin was the sole compound capable of inhibiting a phase of infection subsequent to virus internalization into the host cells.

Animals↗
PubMed1999

Resolution of microsporidial sinusitis and keratoconjunctivitis by itraconazole treatment.

PURPOSE: To report successful treatment of ocular infection caused by the microsporidium Encephalitozoon cuniculi in a person with acquired immunodeficiency syndrome (AIDS) and nasal and paranasal sinus infection. METHOD: Case report. RESULTS: Microsporidial infection in a person with AIDS and with chronic sinusitis and keratoconjunctivitis was diagnosed by Weber modified trichrome stain and transmission electron microscopy. Symptoms completely resolved with itraconazole treatment (200 mg/day for 8 weeks) after albendazole therapy (400 mg/day for 6 weeks) was unsuccessful. CONCLUSION: Itraconazole can be recommended in ocular, nasal, and paranasal sinus infection caused by E. cuniculi parasites when treatment with albendazole fails.

AIDS-Related Opportunistic Infections↗
PubMed1999

Trichinella papuae n.sp. (Nematoda), a new non-encapsulated species from domestic and sylvatic swine of Papua New Guinea.

Encapsulated and non-encapsulated species of the genus Trichinella are widespread in sylvatic animals in almost all zoogeographical regions. In sylvatic animals from Tasmania (Australian region), only the non-encapsulated species Trichinella pseudospiralis has been reported. Between 1988 and 1998, non-encapsulated larvae of Trichinella were detected in five domestic pigs and six wild boars from a remote area of Papua New Guinea. Morphological, biological, and molecular studies carried out on one strain isolated from a wild boar in 1997 suggest that these parasites belong to a new species, which has been named Trichinella papuae n.sp. This species can be identified by the morphology of muscle larvae, which lack a nurse cell in host muscles, and whose total length is one-third greater than that of the other non-encapsulated species, T. pseudospiralis. Adults of T. papuae do not cross with adults of the other species and genotypes. Muscle larvae of T. papuae are unable to infect birds, whereas those of T. pseudospiralis do. The expansion segment V of the large subunit of the ribosomal DNA differs from that of the other species and genotypes. All of these features allow for the easy identification of T. papuae, even in poorly equipped laboratories. The discovery and identification of a second non-encapsulated species in the Australian region strongly supports the existence of two evolutionary lines in the genus Trichinella, which differ in terms of the capacity of larvae to induce a modification of the muscle cell into a nurse cell.

Animals↗
PubMed1999

[Severe agranulocytosis induced by carbamazepine (Tegretol)].

We describe a case of severe drug-induced agranulocytosis, with the risk of a lethal outcome in a patient with a posttraumatic tetraplegia. Intercurrent complications required numerous medicaments. One month after admission, the neutrophil count decreased for ten days until a nadir of 70.mm-3, associated with an infectious syndrome. The bone marrow biopsy showed a severe granulocyte hypoplasia with absence of final differentiation. Administration of ienograstime (granulocyte stimulating factor) was efficient. In this patient, carbamazepine was the most probable causal factor for agranulocytosis. However, other medicaments, mainly antibiotics, could have been contributing factors.

Acinetobacter Infections↗
PubMed1999

Use of medical resources and quality of life of patients with chronic heart failure: a prospective survey in a large Italian community hospital.

AIMS: To assess the prevalence, clinical characteristics, use of medical resources and quality of life in consecutive patients with chronic heart failure (CHF) hospitalized in a large community hospital during 3 months. METHODS AND RESULTS: The study group included 354 patients with CHF, admitted in the Departments of Internal Medicine (97%) and Cardiology. Median age was 78 years [72;85], 45% were males. CHF was the main diagnosis in 72%; 28% were in NYHA class III and 49% in class IV; 42% had atrial fibrillation. The median hospital stay was 8 days [5;14], in-hospital mortality 9% in those admitted for CHF and 19% in those admitted primarily for other diseases. Patients with CHF occupied 15% of the beds; 1330 ECGs, 389 chest X-rays, 112 echocardiograms and 10 coronary angiograms were performed. A quality of life questionnaire revealed that 82% had problems with mobility, 54% with self-care and 88% with everyday activity. Thirty-nine percent of patients had at least one hospitalization during the previous year. CONCLUSIONS: Ninety-seven percent of hospitalized patients with CHF are admitted in the Internal Medicine wards and occupy 15% of beds. The majority of the patients are 72 years or older, with severe heart failure. The frequency of rehospitalization(s) and mortality rate in this population remains high. Echocardiography is performed only in 27% of patients.

Aged↗
PubMed1999

Gastric cryptosporidiosis: correlation between intensity of infection and histological alterations.

AIMS: A retrospective study was carried out to determine the histopathological alterations of the gastric mucosa associated with the presence of Cryptosporidium parasites in the stomach. METHODS AND RESULTS: Gastric biopsies from eight patients with AIDS and cryptosporidiosis were reviewed. Most individuals were males (7/8, mean age 34.7 years) intravenous drug users (6/8), with very low peripheral blood CD4 lymphocyte counts (< 150/mm3; mean 56/mm3). Endoscopic examination showed no significant mucosal abnormalities in half of the individuals; inflammation was observed in the other four individuals and was associated with erosions in two cases. The lesions observed (reactive changes, oedema, erosions, etc.) are not pathognomonic, since they are seen in most common acute and chronic gastrititis of various aetiologies (toxic, infectious, mechanical). The histological examination showed Cryptosporidium parasites in the antrum-pylorus of all examined persons, whereas only two of them had parasites in the corpus. Modifications of histological features consisted mostly of hyperplastic reactive changes of the gland epithelial and inflammation in the connective tissue of the lamina propria. No clear correlation was found between endoscopy and histological findings, whereas a close correlation between intensity of the infection and degree of histological alterations was observed. CONCLUSION: These findings suggest that, in individuals with AIDS, cryptosporidiosis and severe immunodepression, upper endoscopy with random gastric biopsies should be performed, even in the absence of endoscopically appreciable lesions. The diagnosis of gastric cryptosporidiosis has to rely on histological findings, and pathologists must be aware of the fact that Cryptosporidium parasites are mainly found in areas showing reactive hyperplasia.

AIDS-Related Opportunistic Infections↗
PubMed1999

Diverse T-cell receptor CDR3 length patterns in human CD4+ and CD8+ T lymphocytes from newborns and adults.

T cells are essential in the initiation and maintenance of immune responses. Specific interaction between T cells and a presumptive antigen occurs through recognition of an MHC-peptide complex by the T-cell receptor (TCR). The complementarity-determining region (CDR) 3 of the TCR has direct contact with the peptide. Here we describe CDR3 length variability of six different TCRBV gene families of CD4+ and CD8+ umbilical cord (UC) and peripheral blood (PB) T cells. Amplified products spanning the TCR CDR3 regions from CD4+ PB, CD4+ UC and CD8+ UC blood T cells typically displayed Gaussian-like distributions. In contrast, profound and frequent perturbations were recorded in CD8+ PB lymphocytes, with a non-Gaussian pattern in more than half of the samples studied. A substantial portion of the perturbed CD8+ subsets were clonal or oligoclonal, as determined by CDR3-length restriction, TCRBJ gene usage and nucleotide sequencing. This implies that the conditions for shaping and maintenance of the peripheral TCR repertoire are profoundly different for CD8+ and CD4+ T cells.

Adult↗
PubMed1999

Improved high-temperature expansion and critical equation of state of three-dimensional Ising-like systems.

High-temperature series are computed for a generalized three-dimensional Ising model with arbitrary potential. Three specific "improved" potentials (suppressing leading scaling corrections) are selected by Monte Carlo computation. Critical exponents are extracted from high-temperature series specialized to improved potentials, achieving high accuracy; our best estimates are gamma=1.2371(4), nu=0.630 02(23), alpha=0.1099(7), eta=0.0364(4), beta=0.326 48(18). By the same technique, the coefficients of the small-field expansion for the effective potential (Helmholtz free energy) are computed. These results are applied to the construction of parametric representations of the critical equation of state. A systematic approximation scheme, based on a global stationarity condition, is introduced (the lowest-order approximation reproduces the linear parametric model). This scheme is used for an accurate determination of universal ratios of amplitudes. A comparison with other theoretical and experimental determinations of universal quantities is presented.

Journal Article↗
PubMed1999

Evidence for NMDA and mGlu receptor-dependent long-term potentiation of mossy fiber-granule cell transmission in rat cerebellum.

Long-term potentiation (LTP) is a form of synaptic plasticity that can be revealed at numerous hippocampal and neocortical synapses following high-frequency activation of N-methyl--aspartate (NMDA) receptors. However, it was not known whether LTP could be induced at the mossy fiber-granule cell relay of cerebellum. This is a particularly interesting issue because theories of the cerebellum do not consider or even explicitly negate the existence of mossy fiber-granule cell synaptic plasticity. Here we show that high-frequency mossy fiber stimulation paired with granule cell membrane depolarization (-40 mV) leads to LTP of granule cell excitatory postsynaptic currents (EPSCs). Pairing with a relatively hyperpolarized potential (-60 mV) or in the presence of NMDA receptor blockers [5-amino--phosphonovaleric acid (APV) and 7-chloro-kynurenic acid (7-Cl-Kyn)] prevented LTP, suggesting that the induction process involves a voltage-dependent NMDA receptor activation. Metabotropic glutamate receptors were also involved because blocking them with (+)-alpha-methyl-4-carboxyphenyl-glycine (MCPG) prevented potentiation. At the cytoplasmic level, EPSC potentiation required a Ca2+ increase and protein kinase C (PKC) activation. Potentiation was expressed through an increase in both the NMDA and non-NMDA receptor-mediated current and by an NMDA current slowdown, suggesting that complex mechanisms control synaptic efficacy during LTP. LTP at the mossy fiber-granule cell synapse provides the cerebellar network with a large reservoir for memory storage, which may be needed to optimize pattern recognition and, ultimately, cerebellar learning and computation.

Animals↗
PubMed1999

Endometrial morphology and ultrasound vascular findings. A randomized trial after intramuscular and vaginal progesterone supplementation in IVF.

Luteal-phase supplementation has proved necessary in Gn-RH analog and human gonadotropin-stimulated cycles. We studied the effects of vaginally and intramuscularly delivered progesterone on the endometrium. Thirty patients enrolled in an IVF program without embryo transfer due to absence of fertilization were included in the study. Patients were randomly allocated to two treatment groups. Group A (n = 15) was administered 200 mg progesterone b.i.d. by the vaginal route (Esolut, Angelini) starting on the day of oocyte pick up and group B (n = 15) was given 100 mg intramuscular progesterone once daily (Prontogest, Amsa). Six days after HCG administration, biopsies were obtained for endometrial histological maturation and estrogen (ER) and progesterone (PR) receptor analyses. In addition, ultrasound measurements of endometrial thickness were made and uterine and myometrial artery flow was determined. Serum concentrations of estriol and progesterone were measured on the day of HCG, at oocyte pick up and at endometrial biopsy. The two treatment groups were similar in terms of follicular phase parameters during superovulation with Gn-RH analog and gonadotropin. Histologic, receptor and ultrasonographic analyses showed no significant differences between the two treatment groups. Our results indicate that both intramuscular and vaginal progesterone are equally effective on the endometrium.

Administration, Intravaginal↗
PubMed1999

Effects of weight loss on body composition and pulmonary function.

BACKGROUND: The relationship between obesity, impaired respiratory function and weight loss is established. OBJECTIVE: Some aspects need further elucidation: the different impact of the pathological modifications of body compartments (total and regional fat mass and lean body mass) on respiratory function, the choice of a restricted diet, the relationship between the modifications of body compartments and the variations in respiratory parameters after weight loss. METHODS: The restricted diet was elaborated according to the traditional Mediterranean diet. In a series of 16 obese patients, respiratory function was assessed by spirometry; body composition was assessed by dual-energy X-ray absorptiometry, allowing the direct estimation of total and segmental body fat and lean body mass. RESULTS: Weight loss was sustained mainly by fat mass decrease, mostly upper body fat. Total and truncal lean body mass were not affected. Lung volumes and function were improved. A correlation was observed between lean body mass and respiratory parameters, and was unmodified after weight loss. CONCLUSIONS: Mediterranean-style restricted diet was well accepted and enabled a selective decrease in fat mass, with a good improvement in lung function. Truncal fat (as well as abdominal fat) was decreased, while truncal lean body mass (i.e. respiratory muscles) were not affected, as expected in obese subjects with respiration problems.

Absorptiometry, Photon↗
PubMed1999

Measuring evoked responses in multiple sclerosis.

Evoked potentials (EPs) have been widely utilised in Multiple Sclerosis (MS) patients to demonstrate the involvement of sensory and motor pathways. Their diagnostic value is based on the ability to reveal clinically silent lesions and to objectivate the central nervous system damage in patients who complain frequently of vague and indefinite disturbances which frequently occurs in the early phases of the disease. The advent of magnetic resonance imaging (MRI) techniques has greatly reduced the clinical utilisation of EPs, which is not fully justifiable, as the information provided by EPs are quite different from those provided by MRI. The abnormalities of evoked responses reflect the global damage of the evoked nervous pathway and are significantly correlated with the clinical findings, while the vast majority of MRI lesions are not associated to symptoms and signs. Transversal and longitudinal studies have demonstrated that EP changes in MS are more strictly related to disability than MRI lesion burden. On the contrary, MRI is more sensitive than EPs in revealing the disease activity. Evoked responses modifications observed in MS are not disease-specific; moreover longitudinal studies showed latency and morphology changes of evoked responses not always related to clinical changes. Such a dissociation can be explained both by technical factors and by subclinical disease activity. To reduce the negative impact of technical aspects, only reproducible parameters of the evoked responses should be used to monitor disease evolution and therapeutic interventions.

Brain↗
PubMed1999

Local invasion of gastric cancer: CT findings and pathologic correlation using 5-mm incremental scanning, hypotonia, and water filling.

OBJECTIVE: Our purpose was to assess the accuracy of CT with drug-induced hypotonia and water filling in revealing the depth of tumor invasion of the gastric wall, according to the T factor of TNM classification, and to verify the capability of this technique in differentiating diffuse from intestinal gastric cancer. SUBJECTS AND METHODS: Forty patients (age range, 35-78 years) with histologically proven gastric tumors underwent CT, in the prone position, with drug-induced hypotonia and water filling. The images were prospectively reviewed by two radiologists who were asked to assess the depth of tumor invasion in the gastric wall. The thickening of the hypodense layer and the contrast enhancement of lesion were measured. RESULTS: CT correctly assessed gastric wall invasion in 77% and 82% of cases for observers A and B, respectively; overstaging was 20% and 15%, respectively; and understaging occurred in 3% of cases for both observers. Diagnostic sensitivity for serosal invasion was 100% for both observers; specificity was 80% and 87%, respectively. Substantial agreement between the observers was obtained (kappa = .6). Diffuse and intestinal cancers could be differentiated by CT in 92% of cases, considering the thickening of the hypoattenuating layer of the gastric wall (diffuse cancer: 7 +/- 1.2 mm; intestinal cancer: 1.4 +/- 0.4 mm) and contrast enhancement (diffuse cancer: 85 +/- 8.2 H; intestinal cancer: 51 +/- 3 H). CONCLUSION: CT with patients in a drug-induced hypotonia and in a prone position, and using water filling, is a promising technique for evaluating the depth of tumor invasion and for differentiating intestinal from diffuse gastric cancer.

Adult↗
PubMed1999

Mothers and vaccination: knowledge, attitudes, and behaviour in Italy.

The study evaluates knowledge, attitudes, and behaviour of mothers regarding the immunization of 841 infants who attended public kindergarten in Cassino and Crotone, Italy. Overall, 57.8% of mothers were aware about all four mandatory vaccinations for infants (poliomyelitis, tetanus, diphtheria, hepatitis B). The results of a multiple logistic regression analysis showed that this knowledge was significantly greater among mothers with a higher education level and among those who were older at the time of the child's birth. Respondents' attitudes towards the utility of vaccinations for preventing infectious diseases were very favourable. Almost all children (94.4%) were vaccinated with all three doses of diphtheria-tetanus (DT), oral poliovirus vaccine (OPV), and hepatitis B. The proportion of children vaccinated who received all three doses of OPV, DT or diphtheria-tetanus-pertussis (DTP), and hepatitis B vaccines within 1 month of becoming age-eligible ranged from 56.6% for the third dose of hepatitis B to 95.7% for the first dose of OPV. Results of the regression analysis performed on the responses of mothers who had adhered to the schedule for all mandatory vaccinations indicated that birth order significantly predicted vaccination nonadherence, since children who had at least one older sibling in the household were significantly less likely to be age-appropriately vaccinated. The coverage for the optional vaccines was only 22.5% and 31% for measles-mumps-rubella and for all three doses against pertussis, respectively. Education programmes promoting paediatric immunization, accessibility, and follow-up should be targeted to the entire population.

Adult↗
PubMed1999

Interventional radiology in the treatment of renal artery stenosis.

Percutaneous transluminal renal angioplasty (PTRA) alone or in combination with stent implantation, is increasingly used as an alternative technique to surgical revascularization for treatment of renal artery stenosis (RAS) wich may cause hypertension or jeopardize renal function. Herein we report the results obtained with 305 PTRAs performed in 242 hypertensive patients, 144 of whom had atherosclerotic RAS, 69 fibromuscolar dysplasia, 15 Ras in transplanted kidneys, 6 restenosis in surgically revascularized kidneys, 4 Takayasu arteritis and 4 neurofibromatosis. Stents were implanted in 68 cases, mostly in atherosclerotic stenoses. The technical success was achieved in 261 arteries (85.6%), with 33 failures (10.8%) and 11 (3.6%) procedures not completed for anatomical reasons. PTRA related complications were observed in 23 cases (7.5%), but no fatalities occurred. An overall benefit on blood pressure control was observed in 41% of patients with atherosclerotic RAS and in 68% of those with fibromuscolar dysplasia. It appears that independently from the ethiology PTRA is technically effective in correcting RAS; yet the position of PTRA with respect to that of medical or surgical treatment needs to be better delineated through randomized, controlled studies aimed at comparing the clinical efficacies of these different approaches.

Adult↗