Biomedical subjects

D Rossi

Publications and source records attributed to D Rossi.

At least 109 records · Page 6Linked to original sources

PubMed1997

[Anti-Chlamydia pneumoniae antibodies and production of interleukin 6 in acute myocardial infarct].

UNLABELLED: Chlamydia pneumoniae (C.p.) has been correlated with acute myocardial infarction (AMI). High levels of anti-C.p. antibodies and circulating immune complexes containing C.p. lypopolyaaccharide (LPS) antigens have been demonstrated in AMI. LPS antigen and especially Chlamydial LPS is one of the best antigen and it is also a very good Interleukin inductor. Moreover, interleukin 6 (IL-6) has been observed in AMI patients. The aim of our study was to assess the possible relationships between anti-C.p. immune response and IL-6 production in AMI patients. We studied 17 consecutive patients with myocardial infarction (12 males and 5 females; mean age 62; range 46-72). Blood samples were obtained immediately after hospital admission. There were 17 control subjects (HCM) (mean age 62; range 45-72) who were matched for the main coronary risk factors (gender, age, diabetes, hypertension, hypercolesterolemia, smoking, family history of ischemic heart disease). In addition, we evaluated the AMI patients in a one-year follow-up study (FU). RESULTS: High levels of C.p. IgG MIF were found in 82.3% of our AMI patients and in 29.4% of HCM subjects (p = 0.0000065). IgA-MIF were 70.5% in AMI patients and 29.4% in HCM (p = 0.0042). High levels of C.p. IgG and IgA anti-LPS were found, with a very high prevalence rate of 76.4% and 64.7% in AMI patients, and both rates were 47.0% (p = 0.158; p = 0.489) in HCM. Very high levels of IL-6 were found (m = 54.38 pg/ml) in 100% of the AMI patients (normal values in our population: 0-10.86 pg/ml) and only detectable levels in 5.8% of HCM. A good linear correlation was demonstrated between IL-6 and IgA levels in the first sample (r = 0.655). The high levels of anti-C.p. IgG, IgA and IL-6, with a good correlation between IL-6 and IgA levels, may confirm the presence of an active infection and probably of a reinfection.

Acute Disease↗

PubMed1997

[The complement system in kidney diseases].

The multifaceted relations between complement system and immune-mediated nephropathies are reviewed. Several conditions in which either the complement activation induces renal damage without hypocomplementemia or hypocomplementemia occurs in the absence of circulating IC are reported as well as disorders in which immune complexes promote hypocomplementemia. The complement system is involved in the clearance of immune complexes, both modifying the immune complex size and favouring the physiologic neutralization by the erythrocyte transport system. In certain pathological conditions the immune complex intrinsic characteristic or genetic abnormalities prevent efficient removal from the blood stream. The purpose of the present review is to summarize these conditions, briefly describing their pathological consequences, and indicate a simple scheme to correctly interpret the biochemical abnormalities of the complement system in nephropathology.

Complement System Proteins↗

PubMed1997

[Uretero-arterial fistulas: report of 2 cases and review of the literature].

Uretero-arterial fistulas are rare. The authors report two new cases complicating iliac vascular surgery. These fistulas occurred in a particular context: aorto-iliac disease, neoplasm and pelvic radiotherapy. Prolonged ureteric catheterisation is a risk factor found in 65% of cases. The clinical diagnosis is difficult and must be suggested in the presence of episodes of haematuria, sometimes minimal and intermittent, but often cataclysmic. The clinical context is highly suggestive of the diagnosis. The most useful complementary investigations are arteriography and retrograde ureteropyelography. Surgical treatment is complex, as it is performed in an emergency context in patients with a poor general state and it must treat both the vascular and the urological problem. Embolization can be proposed in some cases. The prognosis remains serious due to the frequency and severity of postoperative complications, which is why this disease must be investigated in all patients at risk.

Aged↗

PubMed1996

Assessment of right ventricular function in patients with congestive heart failure by echocardiographic automated boundary detection.

In patients with chronic heart failure, echocardiographic automated boundary detection (ABD) can reliably assess right ventricular function. The measurements obtained by ABD were highly reproducible, strongly correlated with radionuclide right ventricular ejection fraction, and superior to those obtained by conventional manual echocardiographic methods.

Electrocardiography↗

PubMed1996

Anion conductance behavior of the glutamate uptake carrier in salamander retinal glial cells.

Glutamate uptake is driven by the cotransport of Na+ ions, the countertransport of K+ ions, and either the countertransport of OH- or the cotransport of H+ ions. In addition, activating glutamate uptake carriers has been shown to lead to activation of an anion conductance present in the carrier structure. Here we characterize the ion selectivity and gating of this anion conductance. The conductance is small with Cl- as the permeant anion, but it is large with NO3- or ClO4- present, undermining the earlier use of NO3- and ClO4- to suggest that OH- countertransport rather than H+ cotransport helps drive uptake. Activation of the anion conductance can be evoked by extra- or intracellular glutamate and can occur even when glutamate transport is inhibited. By running the carrier backward and detecting glutamate release with AMPA receptors in neurons placed near the glial cells, we show that anion flux is not coupled thermodynamically to glutamate movement, but OH-/H+ transport is. The possibility that cell excitability is modulated by the anion conductance associated with glutamate uptake suggests a target for therapeutic drugs to reduce glutamate release in conditions like epilepsy.

Amino Acid Transport System X-AG↗

PubMed1996

cDNA cloning reveals a tissue specific expression of alternatively spliced transcripts of the ryanodine receptor type 3 (RyR3) calcium release channel.

Ryanodine receptors (RyRs) are a family of intracellular calcium release channels. Three cDNAs encoding different isoforms of RyR have been identified and cloned. We report the complete sequence of the mink RyR3 cDNA and the characterization of three alternative spliced regions. The first two splicing sites are represented by insertions of five and six amino acids, respectively. The third site is represented by a mutually exclusive splicing. The tissue distribution of the alternatively spliced transcripts revealed a ubiquitous expression of splicing site I and a differential distribution of sites II and III, indicating that a further level of complexity in RyR3 expression may result from alternative splicings in this gene.

Alternative Splicing↗

PubMed1996

Peroxynitrite inhibits glutamate transporter subtypes.

The reuptake of glutamate in neurons and astrocytes terminates excitatory signals and prevents the persistence of excitotoxic levels of glutamate in the synaptic cleft. This process is inhibited by oxygen radicals and hydrogen peroxide (H2O2). Here we show that another biological oxidant, peroxynitrite (ONOO-), formed by combination of superoxide (O2-) and nitric oxide (NO), potently inhibits glutamate uptake by purified or recombinant high affinity glutamate transporters reconstituted in liposomes. ONOO- reduces selectively the Vmax of transport; its action is fast (reaching > or = 90% within 20 s), dose-dependent (50% inhibition at 50 microM), persistent upon ONOO- (or by product) removal, and insensitive to the presence of the lipid antioxidant vitamin E in the liposomal membranes. Therefore, it likely depends on direct interaction of ONOO- with the glutamate transporters. Three distinct recombinant glutamate transporters from the rat brain, GLT1, GLAST, and EAAC1, exhibit identical sensitivity to ONOO . H2O2 also inhibits reconstituted transport, and its action matches that of ONOO- on all respects; however, this is observed only with 5-10 mM H202 and after prolonged exposure (10 min) in highly oxygenated buffer. NO, released from NO donors (up to 10 mM), does not modify reconstituted glutamate uptake, although in parallel conditions it promotes cGMP formation in synaptosomal cytosolic fraction. Overall, our results suggest that the glutamate transporters contain conserved sites in their structures conferring vulnerability to ONOO- and other oxidants.

ATP-Binding Cassette Transporters↗

PubMed1996

Synthesis and activity of the glutathione analogue gamma-(L-gamma-oxaglutamyl)-L-cysteinyl-glycine.

An efficient synthesis of the backbone modified glutathione analogue gamma-(L-gamma-oxaglutamyl)-L-cysteinyl-glycine (7), characterized by the presence of an urethane O-CO-NH linkage replacing the gamma-glutamylic CH2CO-NH fragment is described. The new analogue has been fully characterized by 1H- and 13C-NMR, and FAB-MS. Compound 7 was tested for inhibition of gamma-glutamyl-transferase activity and was found to be a non-competitive inhibitor of hog kidney gamma-glutamyltransferase (EC 2.3.2.2).

Animals↗

PubMed1996

Multimodal biochemical modulation of 5-fluorouracil by leucovorin, methotrexate, and interferon alpha in patients with advanced colorectal cancer.

A total of 26 patients with advanced colorectal cancer received 60 mg/m2 methotrexate i.v. on days 1-4; 400 mg/m2 5-fluorouracil i.v. on days 2, 3, 5, and 6; and 100 mg/m2 6S-leucovorin i.v. on days 2, 3, 5, and 6. Interferon-alpha 2b at a dose of 3 million U was given i.m. daily for the 6 days of chemotherapy. Courses were repeated every 3 weeks. There were four partial responses for a response rate of 15% (95% confidence interval 2-28%): In all, 14 patients expressed grade 3 toxicity; 9 patients had diarrhea, 3 had stomatitis, and 2 developed leukopenia. In conclusion, multimodal biochemical modulation of 5-fluorouracil, at least on this schedule, does not seem to be effective, as it results in severe toxicity.

Adult↗

PubMed1996

Microsatellite instability in IVS3 of murine c-fes gene: tumor-associated rearrangement and mammalian divergence.

The murine lymphomacrophage hybrids ESb, EbF1, EbF2-c4, which express c-fes constitutively, were found by Southern analysis to bear a c-fes deletion of almost 100 bp. The deleted allele was transmitted to the metastatic hybrids by their nonexpressing, poorly metastatic T-lymphoma progenitor Eb, which also has a structurally normal c-fes allele. PCR amplification and sequencing of fes cDNA spanning exons 3-5, where the deletion mapped, ruled out any involvement of coding sequences in the rearrangement. PCR amplification of the as yet unsequenced murine c-fes IVS3 and IVS4 showed they are about 50% longer than their human and feline homologs. Sequencing of IVS4 showed no difference between tumor and control DNA. Sequencing of part of the approximately 2600-bp IVS3 was guided by the restriction analysis of PCR products from control and hybrid DNAs. This showed that differences from the control appeared to be mainly located in the 900-bp HindIII-EcoRI fragment, localized in the middle of IVS3. As all three hybrids had the same restriction map, this fragment was sequenced in one of them (ESb). A run of >200 CA repeats was found in control DNA, and a reduction in the CAn microsatellite accounted for most of the c-fes deletion in the ESb hybrid. Interestingly, the 50% reduction in the size of human and feline c-fes IVS3 as compared with the murine homolog is mostly due to contraction of the same microsatellite.

Animals↗

PubMed1996

Sexual functioning among women with physical disabilities.

OBJECTIVE: Three a priori hypotheses were tested: (1) There are significant differences in sociosexual behaviors of women with physical disabilities compared with women without disabilities; (2) the sexual functioning of women with disabilities is significantly related to age at onset of disability; (3) psychological factors explain more of the variance in the sexual functioning of women with physical disabilities than do disability, social and environmental factors. DESIGN: Case-comparison study using written survey. SETTING: General community. PARTICIPANTS: The questionnaire was mailed to 1,150 women with physical disabilities who were recruited as volunteers or through independent living centers. Each woman gave a second copy of the questionnaire to an able-bodied female friend, which comprised the comparison group. The response rate was 45%, with 475 cases and 425 comparisons eligible to participate. The most common disability type was spinal cord injury (24%), followed by polio (18%), muscular dystrophy (11%), cerebral palsy (11%), multiple sclerosis (10%), joint disorders (7%), and skeletal abnormalities (5%). INTERVENTIONS: None. MAIN OUTCOME MEASURES: Sexual-functioning, consisting of four factors: (1) sexual desire, (2) sexual activity, (3) sexual response, (4) sexual satisfaction. RESULTS: Highly significant differences were found in level of sexual activity (p = .000001), response (p = .000009), and satisfaction (p=.000001) between women with and without disabilities. No significant differences were found between groups on sexual desire. Severity of disability was not significantly related to level of sexual activity. CONCLUSIONS: Psychological and social factors exert a strong impact on the sexual functioning of women with physical disabilities. Further investigations is needed of the effect of social environment on development of self-esteem and sexual self-image, and how these influences affect levels of sexual functioning in women with physical disabilities.

Adolescent↗

PubMed1996

Expression pattern of c-sis, c-fos and c-jun in human placenta and embryofetal organs.

The expression pattern of c-sis, c-fos and c-jun was investigated in placenta and embryofetal organ specimens from the first trimester. Northern analysis of the placentae showed c-sis transcripts and c-fos expression. Northern analysis of the same genes in embryofetal organs pointed to the brain as the only organ where consistent transcriptional activity could be observed. RT-PCR analysis of c-fos and c-jun in placentae, staged at four different time periods in pregnancy, allowed to detect the expected fragments in all cases. The same was true when c-fos and c-jun were analyzed at the 13th week of gestation in all the embryofetal organs.

Blotting, Northern↗

PubMed1996

[The Miami pouch: a reliable continent urinary diversion after pelvic exenteration].

OBJECTIVES: To describe the technique and present the results obtained with the Miami reservoir, a continent urinary diversion, after pelvic exenteration for advanced gynaecological tumours. METHODS: A Miami reservoir was performed in 12 patients between January 1993 and January 1995. A detubed right colonic reservoir was created using automatic resorbable staples. The ureters were reimplanted into the reservoir using an anti-reflux system and continence was ensured by forming a tube with the terminal loop of ileum and by using a Bauhin valve, which can be reinforced when it is incompetent. Regular postoperative follow-up was conducted (6 to 26 months) with monitoring of laboratory parameters, intravenous urography, opacification of the reservoir, urodynamic assessment of the continent diversion. RESULTS: There were no surgical complications related to the urinary diversion. Urinary continence was obtained in every case and after medical treatment of residual peristaltic contractions of the detubed colonic reservoir in 2 patients. Protection of the upper urinary tract was satisfactory after 2 years of follow-up, without stenosis or reflux of the uretero-colonic anastomoses. The mean capacity of the colonic reservoir was 465.5 +/- 101 ml at 6 months, with filling pressures lower than 20 cm H2O. CONCLUSION: The Miami reservoir is a continent urinary diversion which is relatively easy to perform and reliable in terms of continence and protection of upper tract. However, a longer postoperative follow-up is required. The quality of life of young patients after pelvic exenteration is improved due to this type of contingent diversion which avoids the need for an abdominal urine collector, although it requires intermittent self-catheterization.

Adult↗

PubMed1996

[Glomerulonephritis in the elderly].

The authors present a clinical analysis of the literature data regarding aged patients affected with glomerulonephritis (GN) and of 115 GN patients aged more than 65 years, biopsied in their own Center. Complications of renal biopsy, including the subclinical ones, were found in 19.1% of old patients compared to 19.2% of younger patients (p = NS), major complications in 5 and 1.4% respectively (p = NS). The most frequent GN was membranous GN (MGN) (27.8%), followed by IgA-GN (12%) and rapidly progressive GN (RPGN), idiopathic (8.6%) or secondary to vasculitis (8.6%). Eighteen out of 32 old MGN patients treated with alternated courses of steroids and immunosuppressive drugs for 6 months were compared to 32 MGN patients aged < 65 years identically treated. Complete remission was observed in 27.7% of cases and partial remission in 38.8% (p = NS). Complications of treatment were similar in the two groups of patients (p = NS). Patients with RPGN were treated with steroids (17 patients) plus immunosuppressive drugs (15 patients) and plasma exchange (13 patients). Systemic symptoms disappeared in 13/14 patients; ANCA became negative in all the 5 patients in whom they were detected; a 50% reduction of serum creatinine was obtained in 12 patients. These patients were compared to a control group of 26 patients aged < 65 years. Amelioration of renal function was evidenced more frequently among old patients with vasculitis (p < 0.05). Complications of treatment were more frequent among old patients with idiopathic RPGN (p < 0.05), but severe in only 1 case. Our data and data from the literature support the opportunity to perform renal biopsy in aged people, because it is as safe as in the younger population and allows a rational basis for treatment of GN. Clinical responses are similar to those of younger patients. Complications of treatment seem to be more frequent in old patients, but can be limited by some technical precautions and careful clinical monitorization.

Age Distribution↗

PubMed1996

[Surgical treatment of La Peyronie's disease].

Lapeyronie disease is responsible for curvature of the penis, making sexual intercourse painful or even impossible. Surgical treatment can be proposed when the plaque has remained stable for at least 6 months and after failure of medical treatment. It is designed to restore erection allowing penetration. Examination after an intracavernous test allows assessment of the deformity and the quality of erection. These two objective parameters appear to be decisive in the choice of the most appropriate technique. Two types of methods are available: cavernoplasties (resection-plication of the tunica albuginea, excision-graft) and prosthesis implantations (semirigid, inflatable and flexible implants). This paper reviews the various surgical techniques and proposes a decisional flow-chart based on the results of the intracavernous test.

Humans↗

PubMed1995

Arachidonic acid inhibits a purified and reconstituted glutamate transporter directly from the water phase and not via the phospholipid membrane.

Glutamate is believed to be the major excitatory transmitter in the mammalian central nervous system. Keeping the extracellular concentration of glutamate low, the glutamate transporters are required for normal brain function. Arachidonic acid (AA) inhibits glutamate uptake in relatively intact preparations (cells, tissue slices, and synaptosomes (Rhoads, D.E., Ockner, R. K., Peterson, N. A., and Raghupathy, E. (1983) Biochemistry 22, 1965-1970 and Volterra, A., Trotti, D., Cassutti, P., Tromba, C., Salvaggio, A., Melcangi, R. C., and Racagni, G. (1992b) J. Neurochem. 59, 600-606). The present study demonstrates that the effect of AA occurs also in a reconstituted system, consisting of a purified glutamate transporter protein incorporated into artificial cell membranes (liposomes). The characteristics of the AA effect in this system and in intact cells are similar with regard to specificity, sensitivity, time course, changes in Vmax, and affinity. AA-ethyl ester is inactive, suggesting that the free carboxylic group is required for inhibitory activity. When incubated with proteoliposomes, AA (300 microM, 15 min) mostly partitions to the lipid phase (lipid/water about 95:5). However, uptake inhibition is abolished by rapid dilution (6.5-fold) of the incubation medium (water phase), a procedure that does not modify the amount of AA associated with lipids. On the contrary, inhibition remains sustained if the same dilution volume contains as little as 5 microM AA, a concentration inactive before saturation of liposome lipids with 300 microM AA. The same degree of inhibition (60%) is obtained by 5 microM AA following preincubation with the inactive AA-ethyl ester (300 microM) instead of AA. The lipids apparently inactivate AA by extracting it from the water phase. The results suggest that AA acts on the transporter from the water phase rather than via the membrane. This could be true for other proteins as well since gamma-aminobutyric acid uptake is similarly affected by AA.

ATP-Binding Cassette Transporters↗

PubMed1995

Effect of severity of surgery on metabolic control and insulin requirements in insulin-dependent diabetic patients.

We have evaluated insulin requirements and the relationship between hormonal variables, changes in blood glucose and insulin requirements in insulin-dependent diabetic patients undergoing two degrees of severity of surgery: minor (vitrectomy) and major (gastrectomy, bowel resection, hip replacement). The study began just before induction and ended 2 h after surgery. Blood glucose concentrations were comparable in both groups but the total amount of insulin given was significantly greater in the major surgery group. Plasma noradrenaline and cortisol concentrations increased significantly during major surgery and there were significant correlations between the increase in these counter-regulatory hormones and the amount of insulin administered. We conclude that the metabolic changes occurring during surgery were small, but at the cost of a marked increase in insulin requirements during major surgery. Increased sympathetic nervous system activity seems to have been implicated in the increase in insulin requirements.

Adult↗

PubMed1995

Synthesis and activity of the glutathione analogue gamma-(L-gamma-azaglutamyl)-L-cysteinyl-glycine.

The backbone-modified glutathione analogue gamma-(L-gamma-azaglutamyl)-L-cysteinyl-glycine 7, characterized by the presence of a NHCONH urea linkage deriving from the replacement of the native Glu gamma-CH2 with the aza (NH) group, was synthesized and fully characterized by FAB-MS, 1H- and 13C-NMR. Potential of 7 and its oxidized form 6 as gamma-glutamyltransferase inhibitors was investigated. Both compounds 7 and 6 were found to be competitive inhibitors of hog kidney gamma-glutamyltransferase (EC 2.3.2.2.) by binding at the donor site: the reduced analogue is a more efficient inhibitor than glutathione of the gamma-glutamyl transfer reaction. Inhibition at the acceptor site, which is also present, appears to be more complex. In particular, un-competitive inhibition is observed for compound 7. The results indicate that gamma-azapeptides of type 7 may represent interesting targets in the search for stable inhibitors of gamma-glutamyltransferases.

Animals↗