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A Sabbatini

Publications and source records attributed to A Sabbatini.

At least 19 recordsLinked to original sources
PubMed2001

Recent trends in the HIV epidemic among injecting drug users in Northern Italy, 1993-1999.

OBJECTIVE: To monitor and describe the time trends of the HIV epidemic among intravenous drug users (IDU) attending drug dependence treatment centres (DDTC) in Northern Italy. DESIGN: A cohort of all seronegative IDU attending DDTC in Lombardy between 1993 and 1999; all had been tested for HIV at least twice. Periodic sample interview surveys were done to assess risk behaviours. METHODS: The incidence rates of HIV infection were calculated using the person-year (PY) method and expressed as the number of cases per 1000 PY at risk. Background HIV prevalence was calculated by dividing the number of positive cases by the total number of IDU tested at all DDTC in Lombardy. RESULTS: Between 1993 and 1999, 135 seroconversions occurred in 7945 subjects followed for 19 671 PY, yielding an incidence rate of 6.9/1000 PY. Ninety seroconversions occurred among the 6563 males and 45 seroconversions among 1382 females (incidence rates 5.5 and 14.0, respectively). Among the males, the incidence of HIV was 4.5 in those aged less than 25 years and 5.8 in those aged 25 years or more. Among the females, the corresponding figures were 21.1 and 10.3. HIV prevalence decreased over time, and it was higher among females. Sexual behaviours at risk were more common among females. CONCLUSIONS: The incidence of HIV infection among IDU in Northern Italy was stable between 1993 and 1999. The higher incidence and prevalence among females and the different prevalence of risk behaviours between genders suggest an increasing role of heterosexual transmission.

Adult↗
PubMed2000

Surface expression of a glycolytic enzyme, alpha-enolase, recognized by autoantibodies in connective tissue disorders.

In systemic autoimmune diseases, autoantibodies specific for alpha-enolase are detected more frequently in patients with active renal involvement. To analyze the properties of anti-alpha-enolase antibodies and the distribution of the enzyme in the cell, mouse monoclonal and polyclonal antibodies were obtained from mice immunized with a glutathione-S-transferase-alpha-enolase fusion protein. Anti-alpha-enolase antibodies were purified from patient sera on enolase from human kidney. Using these antibodies, the distribution of alpha-enolase in the cell was analyzed in subcellular fractions and in the cell membrane by flow cytometry and immunoprecipitation. Plasminogen binding was studied by an immunoenzymatic assay. We observed that alpha-enolase was present in the cytosol and membrane fractions obtained from kidney and U937 cells. By flow cytometry, mouse polyclonal anti-enolase antibodies, one monoclonal and 7/9 human anti-enolase antibodies bound the membrane of U937 cells. One monoclonal antibody and mouse polyclonal anti-enolase antibodies immunoprecipitated a 48-kDa molecule from surface-labeled U937 cells and this molecule was recognized by rabbit anti-enolase antibodies. Both immunization-induced antibodies and 7/9 autoantibodies from patient sera inhibited the binding of plasminogen to alpha-enolase. The results show that alpha-enolase, an autoantigen in connective tissue diseases, is a cytoplasmic enzyme which is also expressed on the cell membrane, with which it is strongly associated. Anti-alpha-enolase autoantibodies isolated from patient sera recognize the membrane-associated form of the enzyme and/or interfere with its receptor function, thus inhibiting the binding of plasminogen. Autoantibodies specific for alpha-enolase could play a pathogenic role, either by a cytopathic effect or by interfering with membrane fibrinolytic activity.

Animals↗
PubMed2000

Pleural tent after upper lobectomy: a prospective randomized study.

BACKGROUND: The aim of the present study was to assess the cost/efficacy of the pleural tent procedure after upper lobectomy. METHODS: A prospective randomized analysis was performed on 50 patients submitted to upper lobectomy and divided into two groups: group 1 (25 patients) with pleural tent; group 2 (25 patients) without pleural tent. RESULTS: The univariate comparison between the two groups did not show any significant difference in terms of age, gender, spirometry, smoking history, chronic obstructive pulmonary disease index, side of tumor, arterial oxygen tension, arterial carbon dioxide tension, size and location of tumor, presence of pleural adhesions, length of the stapled parenchyma, and operative time. Pleural tent significantly reduced the days of postoperative air leak (1.2 versus 5.8, p = 0.01), chest tubes (5.4 versus 10.4, p = 0.01), and hospital stay (6.9 versus 10.8, p = 0.01). Moreover, no difference was noted between the two groups in terms of pleural effusion in the first postoperative 48 hours, need of postoperative blood transfusion, and occurrence of other complications. CONCLUSIONS: Pleural tenting after upper lobectomy is a safe and effective procedure and its routine use is warranted.

Adult↗
PubMed2000

Fetal pancreatic function in infants of diabetic and rhesus-isoimmunized women.

OBJECTIVE: To measure insulin and glucagon concentrations in amniotic fluid (AF) collected near term in basal conditions and after an arginine test in diabetic, rhesus-isoimmunized, and control pregnant women. METHODS: At baseline, AF was collected from 44 diabetic, 32 rhesus-isoimmunized, and 27 control pregnant women in late pregnancy. Fifty-two diabetic, six rhesus-isoimmunized, and nine control pregnant women had amniocentesis 2 hours after arginine infusion (30 g intravenous/30 minutes) at 33-36 weeks. RESULTS: Baseline AF glucose concentrations were significantly greater in diabetic women than the other conditions, and they related to the gestational age in the women with hemolytic disease of the newborn. Insulin and glucagon AF content of isoimmunized pregnancies overlapped controls, whereas insulin and insulin/glucagon molar ratios were significantly higher, and glucagon values lower, in diabetic pregnancies compared with isoimmunized and control pregnancies. In isoimmunized pregnancies, the AF concentrations of glucose, insulin, and glucagon were correlated with gestational age (less than 34, 34 weeks or more). The samples collected after arginine infusion, compared with those collected at baseline, showed significantly greater insulin and insulin/glucagon molar ratio values in diabetic (28 +/- 5 versus 11 +/- 1 microU/mL, P = .001; 29.4 +/- 1.7 versus 12.0 +/- 2.8, P = .001) and in Rh pregnant women (18 +/- 6 versus 7.7 +/- 0.7 microU/mL, P = .001; 30 +/- 9 versus 3.4 +/- 0.4 I/G, P = .001), whereas no significant difference was observed in the controls. CONCLUSION: Basal islet hormone concentrations in AF are modified by maternal diabetes and further influenced by arginine administration. Arginine produces an AF response that is similar in pregnancies complicated by diabetes mellitus and rhesus-isoimmunization, despite different (hyperglycemia and euglycemia) maternal blood glucose levels.

Adult↗
PubMed2000

Autoantibodies specific for alpha-enolase in systemic autoimmune disorders.

OBJECTIVE: To analyze the presence and specificity of anti-alpha-enolase antibodies in various systemic autoimmune diseases. METHODS: Sera from patients with systemic lupus erythematosus (SLE), mixed cryoglobulinemia (MC), systemic sclerosis (SSc), and rheumatoid arthritis (RA) were tested by immunoblot on partially purified a-enolase from human kidney and on beta- and gamma-enolase. The isotype of anti-enolase antibodies was determined by means of isotype-specific monoclonal antibodies. RESULTS: IgG anti-alpha-enolase antibodies were detected in 9/33 (27%) SLE sera (6/9 patients had active renal disease), in 6/19 sera from patients with MC and nephritis, in 0/15 sera from MC patients without renal involvement, in 6/20 (30%) SSc sera, in 2/35 (6%) disease controls with RA, and in 2/32 (6%) healthy controls. The antibodies were not species-specific, but in most cases were specific for the alpha isoform of enolase. The anti-enolase immune response was not isotypically restricted. In half of the patients with SLE the anti-alpha-enolase and anti-DNA antibodies constituted distinct antibody populations, while in the other half a partial overlap of the 2 antibody specificities was observed. CONCLUSION: Anti-alpha-enolase antibodies can frequently be detected in systemic autoimmune disorders. In SLE and MC they are associated with nephritis and in SSc they are associated with severe endothelial damage. Alpha-enolase is ubiquitous, but is highly expressed in the kidney and also on the membrane of several cell types including endothelial cells. Thus, anti-alpha-enolase antibodies could contribute to renal injury not only by the local formation of immune complexes, but also by direct damage to endothelial cells.

Adult↗
PubMed1999

Paraneoplastic syndromes in 68 cases of resectable non-small cell lung carcinoma: can they help in early detection?

The aim of this study was to assess the importance of paraneoplastic syndromes as an early sign of non-small cell lung cancer (NSCLC). A procedure for searching paraneoplastic syndromes, based on 40 years of reports in the literature, was established and the prevalence of paraneoplastic syndromes estimated in 68 patients with resectable NSCLC. Stages I and II were considered eligible for surgery straight away. Patients in Stage IIIA underwent surgery if partially or completely responsive to three courses of neo-adjuvant chemotherapy. Paraneoplastic syndromes were assessed and confirmed in nine patients (13%). Motor-sensory neuropathy, arthritis and arthralgias to the knees, periarthritis to the shoulder, hypertrophic osteopathy, clubbing, pruritus were observed. Only three patients with painful osteoarthropathies were diagnosed with NSCLC by tracing their paraneoplastic syndrome, whereas most of them (36/68) were diagnosed incidentally through a chest radiograph taken for tumour-unrelated symptoms. A careful research of paraneoplastic syndromes in high risk patients may guide the doctor to a resectable NSCLC diagnosis. Recent onset arthritis and arthralgias, which cannot be explained otherwise, should be considered to be early clues of lung cancer.

Adult↗
PubMed1997

Association of purified skeletal-muscle AMP deaminase with a histidine-proline-rich-glycoprotein-like molecule.

Denaturation of rabbit skeletal-muscle AMP deaminase in acidic medium followed by chromatography on DEAE-cellulose in 8 M urea atpH 8.0 allows separation of two main peptide components of similar apparent molecular mass (75-80 kDa) that we tentatively assume correspond to two different enzyme subunits. Whereas the amino acid composition of one of the two peptides is in good agreement with that derived from the nucleotide sequence of the known rat and human AMPD1 cDNAs, the second component shows much higher contents of proline, glycine and histidine. N-Terminal sequence analysis of the fragments liberated by limited proteolysis with trypsin of the novel peptide reveals a striking similarity to the fragments produced by plasmin cleavage of the rabbit plasma protein called histidine-proline-rich glycoprotein (HPRG). However, some divergence is observed between the sequence of one of the fragments liberated from AMP deaminase by a more extensive trypsinization and rabbit plasma HPRG in the region containing residues 472-477. A fragment with a blocked N-terminus, which was found among those liberated by proteolysis with pepsin of either whole AMP deaminase or the novel component of the enzyme, shows an amino acid composition quite different from that of the N-terminus of the known subunit of AMP deaminase. By coupling this observation with the detection in freshly prepared AMP deaminase of a low yield of the sequence (LTPTDX) corresponding to that of HPRG N-terminus, it can be deduced that in comparison with HPRG, the putative HPRG-like component of AMP deaminase contains an additional fragment with a blocked N-terminus, which is liberated by a proteolytic process during purification of the enzyme. The implications of the association to rabbit skeletal-muscle AMP deaminase of a HPRG-like protein species are discussed.

AMP Deaminase↗
PubMed1997

Phenotypic characteristics and tendency to apoptosis of peripheral blood mononuclear cells from HIV+ long term non progressors.

The aim of this study was to analyze (i) phenotype, (ii) in vitro spontaneous and induced apoptosis, (iii) glutathione (GSH) intracellular content and (iv) inhibitors of apoptosis of potential therapeutical use in peripheral blood mononuclear cells (PBMC) from HIV+ long term non progressors (LTNP), in comparison with progressors (HIV+P) and seronegative controls (HIV-). Three groups of subjects were studied: 15 HIV+P (patients losing >150 CD4+/year), 9 LTNP (subjects infected by HIV for at least 7 years without clinical and immunological signs of progression, with a mean of 898 CD4+/microL) and 18 HIV-. All subjects were living in a large community for former drug addicts, and were matched for age and sex. We used flow cytometry for analyzing PBMC phenotype and apoptosis; high performance liquid chromatography for measuring intracellular GSH content. PBMC phenotype of LTNP shared characteristics with those of both HIV- and HIV+P. Indeed, LTNP showed a normal number CD4+ cells (an inclusion criteria), but significantly increased numbers of CD8+ lymphocytes, activated T cells, CD19+, CD5+ B lymphocytes and CD57+ cells, as well as a decrease in CD19+, CD5- B lymphocytes and CD16+ cells. In LTNP, spontaneous apoptosis was similar to that of HIV- and significantly lower than that of HIV+P. Adding interleukin-2 (IL-2) or nicotinamide (NAM) significantly decreased spontaneous apoptosis in LTNP and HIV+P. Pokeweed mitogen-induced apoptosis was also similar in LTNP and HIV-, but significantly lower than that of HIV+P. In HIV+P, but also in LTNP, spontaneous apoptosis was inversely correlated to the absolute number and percentage of CD4+ cells and directly correlated to the number and percentage of activated T cells present in peripheral blood. GSH intracellular content was greatly decreased in PBMC from HIV+P and slightly, but significantly, reduced in LTNP. Adding 2-deoxy-D-ribose, an agent provoking apoptosis through GSH depletion, to quiescent PBMC resulted in similar levels of massive cell death in the three groups. This phenomenon was equally prevented in the three groups by N-acetyl-cysteine but not by IL-2. A complex immunological situation seems to occur in LTNP. Indeed, PBMC from LTNP are characterized by a normal in vitro tendency to undergo apoptosis despite the presence of a strong activation of their immune system, unexpectedly similar to that of HIV+P. Our data suggest that NAM and IL-2 are possible candidates for reducing spontaneous apoptosis in HIV infection.

Journal Article↗
PubMed1997

Mitochondria alterations and dramatic tendency to undergo apoptosis in peripheral blood lymphocytes during acute HIV syndrome.

OBJECTIVE: To study alterations of mitochondrial membrane potential (delta psi) and the propensity to undergo apoptosis in peripheral blood lymphocytes (PBL) from subjects with acute HIV syndrome; and to evaluate possible modulations of these phenomena by antioxidants that can be used in therapy, such as N-acetyl-cysteine (NAC), nicotinamide (NAM), or L-acetyl-carnitine (LAC). METHODS: Mitochondrial function and the tendency of PBL to undergo spontaneous apoptosis were studied on freshly collected PBL from patients with symptomatic, acute HIV-1 primary infection, which were cultured for different durations in the presence of absence of NAC. NAM or LAC. By a cytofluorimetric method allowing analysis of delta psi in intact cells, we studied the function of these organelles under the different conditions. PBL apoptosis was evaluated by the classic cytofluorimetric method of propidium iodide staining, capable of revealing the typical DNA hypodiploid peak. RESULTS: Significant delta psi alterations and tendency to undergo apoptosis were present in PBL from the subjects we studied. Indeed, when cultured even for a few hours in the absence of any stimulus, a consistent number of cells died. However, the presence of even different levels of NAC, NAM or LAC was able to rescue most of them from apoptosis. Both a fall in delta psi and apoptosis were evident in PBL collected in the earliest phases of the syndrome (before seroconversion), and changed significantly after a few days. A significant correlation was found between spontaneous apoptosis and tumour necrosis factor (TNF)-alpha or p24 plasma levels, as well as between apoptosis and the percentages of circulating CD4+ or CD8+ T cells. CONCLUSIONS: PBL from patients with acute HIV syndrome are characterized by both significant mitochondrial alterations and a dramatic tendency to undergo apoptosis. The use of NAC, NAM or LAC seems to rescue cells through a protective effect on mitochondria, a well-known target for the action of TNF-alpha and for reactive oxygen species, the production of which is strongly induced by this cytokine. Thus, our data could provide the rationale for the use of such agents in addition to antiviral drugs in primary infection.

Acetylcarnitine↗
PubMed1997

Pulmonary arteriovenous fistula in a patient with Rendu-Osler-Weber syndrome.

Pulmonary arteriovenous fistula (PAVF) is an abnormal connection between pulmonary arteries and veins. Patients with PAVF may have the Rendu-Osler-Weber syndrome, a disease transmitted by autosomal dominant mechanisms. Here we describe a case of PAVF in a 56-year-old woman, who was admitted to our department because of dyspnea, hemoptysis, and a mass in the left lower lung found on chest X-ray. The diagnosis of PAVF was suspected according to clinical and physiological criteria and confirmed by magnetic resonance imaging of the chest. The PAVF was removed by left lower lobectomy. Anamnestic and clinical investigations of the patient's relatives led to the diagnosis of the Rendu-Osler-Weber syndrome.

Adult↗
PubMed1997

Blood pressure monitoring in diabetic pregnancy.

Hypertensive disorders which complicate 5-10% of all pregnancies are more frequent in diabetic women. We longitudinally monitored blood pressure (BP) for a 24 h period in 54 diabetic out patients, at each trimester of pregnancy, in order to observe the relationship between the blood pressure behaviour and the main clinical features of these subjects. A relationship was found between blood pressure and the diabetes type. In insulin-dependent diabetes mellitus (IDDM) women, the age of diagnosis and the diabetes duration played the major role whereas, in non insulin-dependent diabetes mellitus (NIDDM) women only the patients' age was correlated with the BP levels. Higher BP levels were found in women belonging to the White class D, and whose diabetes duration was more than 10 years. An interesting correlation was also demonstrated between BP and insulin requirement, in late pregnancy as well as the time of delivery. Early in pregnancy, BP levels, even if within normal range, were undoubtedly higher in those women who developed hypertension compared to those who continued to be normotensive. Daytime BP values were always found higher than night-time BP values but, the physiological biorhythm seemed to be altered at the end of pregnancy.

Adolescent↗
PubMed1997

Telemedicine in the treatment of diabetic pregnancy.

Good diabetic control requires that treatment be continuously adapted to the patient behavior. We investigated whether the use of telemedicine could present an advantage to the management of the diabetic woman during pregnancy. A system completely automatic (DIANET system) was used. Twenty IDDM women participated in the study: 10 treated by telemedicine and 10 by conventional system, at times "entry" (9.5 weeks), "basal" (9.5-16.8 weeks), "1st month" of investigation, and "end" (near delivery). All women used intensified protocols of insulin administration. The treatment with DIANET vs conventional showed a better metabolic control as estimated by profile of blood glucose absolute values (at time "end": values significantly lower before breakfast: 87 +/- 6 vs 104 +/- 4 mg, lunch: 85 +/- 5 vs 104 +/- 4 mg, and after dinner: 102 +/- 5 vs 124 +/- 6 mg). These results were associated with higher insulin doses in the DIANET vs conventional treatment, and a significant reduction of hypoglycemic reaction in both group. Our results suggest that telemedicine-DIANET is a practical way of providing specialist care in the pregnancy area.

Adult↗
PubMed1997

IGF-1 levels in diabetic pregnant women and their infants.

Plasma IGF-1 was measured in 38 diabetic pregnant women (DPW) and in 12 non diabetic pregnant women (NDPW) during the 1st, 2nd and 3rd trimester of pregnancy. IGF-1 was measured in the cord blood of 24 infants of diabetic mothers (IDDM) and IGF-1 in 11 infants of non diabetic mothers (NIDDM). A progressive and significant (p < 0.0001) increase of IGF-1 values was found throughout the pregnancy both in DPW and NDPW IGF-1 (149 +/- 18 ng/ml vs 181 +/- 14 ng/ml, 184 +/- 17 ng/ml vs 232 +/- 25 ng/ml, 279 +/- 20 ng/ml vs 325 +/- 17 ng/ml). Furthermore IGF-1 decreased significantly soon after delivery in both groups of women. In type 1 diabetic pregnant women IGF-1 values were significantly lower than the controlled non diabetic patients. IGF-1 in the cord blood was significantly higher in IDDM than in NIDDM 86 +/- 7 ng/ml and 62 +/- 7 ng/ml respectively (p < 0.03). In addition, DPW plasma levels IGF-1 were positively correlated with the weight of the placenta (r = 0.233, p < 0.03) and negatively correlated with the diabetes duration (r = 0.412, p < 0.05). No correlations were found between IGF-1 cord blood concentrations and gestational age, birth weight and length, but there was a significant correlation with weight percentile (r = 0.846, p < 0.001). No correlation was found between maternal IGF-1 plasma levels and other parameters like insulin need, weight gain, metabolic control and time of delivery.

Adult↗
PubMed1996

Descending necrotizing mediastinitis. Surgical drainage and tracheostomy.

OBJECTIVE: To outline the most appropriate treatment of descending necrotizing mediastinitis. DESIGN: Case series. SETTING: General community, institutional practice, hospitalized care. PATIENTS: Five consecutive cases of descending necrotizing mediastinitis that were treated at our institution from 1983 to 1995. Selection criteria included clinical manifestations of severe cervical infection, characteristic radiographic features, documentation of the mediastinal infection at operation, and establishment of the relationship of the oropharingeal infection with the mediastinal process. Cases of mediastinitis due to perforation of the cervical esophagus were excluded. A cervicothoracic computed tomographic scan was obtained in the last 4 patients on admission. In the first case, computed tomographic scanning was not yet available at our institution. INTERVENTIONS: All patients underwent drainage of the cervical infection through a cervical incision. Mediastinitis was drained by thoracotomy in 2 patients, since the lower mediastinum was involved, whereas 3 patients underwent cervicomediastinal drainage alone. Tracheostomy was performed in 2 patients. RESULTS: All patients survived, with a short hospital stay (mean, 35 days). CONCLUSIONS: Cervicomediastinal drainage is adequate when the descending mediastinitis is limited to the upper mediastinum. Thoracotomy has to be performed only when the process has diffusely spread below the carina. Early diagnosis is crucial, and we strongly recommend a cervicothoracic computed tomographic scan in every patient with deep cervical infection. We consider tracheostomy not always necessary. Adequate early drainage, with the cervical wounds left open, and antibiotic and anti-inflammatory therapy should prevent upper airway obstruction.

Adult↗
PubMed1995

Regulation of skeletal-muscle AMP deaminase: involvement of histidine residues in the pH-dependent inhibition of the rabbit enzyme by ATP.

Reaction of rabbit skeletal-muscle AMP deaminase with a low molar excess of diethyl pyrocarbonate results in conversion of the enzyme into a species with one or two carbethoxylated histidine residues per subunit that retains sensitivity to ATP at pH 7.1 but, unlike the native enzyme, it is not sensitive to regulation by ATP at pH 6.5. This effect mimics that exerted on the enzyme by limited proteolysis with trypsin, which removes the 95-residue N-terminal region from the 80 kDa enzyme subunit. These observations suggest involvement of some histidine residues localized in the region HHEMQAHILH (residues 51-60) in the regulatory mechanism which stabilizes the binding of ATP to its inhibitory site at acidic pH. Carbethoxylation of two histidine residues per subunit abolishes the inhibition by ATP of the proteolysed enzyme at pH 7.1, suggesting the obligatory participation of a second class of histidine residues, localized in the 70 kDa subunit core, in the mechanism of the pH-dependent inhibition of the enzyme by ATP. At a slightly acidic pH, these histidine residues would be positively charged, resulting in a desensitized form of the enzyme similar to that obtained with the carbethoxylation reaction.

AMP Deaminase↗