Search PubMed⌕ Search

Biomedical subjects

M Vecchi

Publications and source records attributed to M Vecchi.

At least 109 records · Page 6Linked to original sources
PubMed1982

[Prevalence of HBsAg and anti-HBs in hospital personnel].

The prevalence of serum HBsAg and Anti-HBs was studied in 201 staff members from two Renal Dialysis Units, one Medical and one Dermatological Division from two Hospitals in the Milano area. The overall prevalence of HBsAg was significantly greater among staff members (8.9%) as compared to controls (4.9%). On the contrary, the prevalence of Anti-HBs was only slightly higher in hospital personnel than in controls. Non-medical staff members (nurses, technicians) showed a prevalence of HBV markers (HBsAg and/or Anti-HBs) twice as high as medical staff members (46.1% vs 23.2%). When the prevalence of HBV markers was correlated to the duration of work in the hospital, a steady increase in the prevalence of Anti-HBs was observed. On the contrary, the prevalence of HBsAg rose in the first 3 years and remained constant thereafter. The prevalence of HBV markers was significantly higher among staff members from Renal Dialysis Units (HBsAg+ and/or Anti-HBs+:50%) than in the personnel from the Medical and Dermatological Divisions (32.4%). However, the difference was solely related to a higher prevalence of Anti-HBs in the former (42% vs 23%). This may reflect a higher risk of infection in Dialysis Units as compared to other Hospital Divisions. However, the difference might be magnified by the frequent use of HBIG in the Dialysis Units personnel.

Adult↗
PubMed1981

Stereoisomers of alpha-tocopheryl acetate--characterization of the samples by physico-chemical methods and determination of biological activities in the rat resorption-gestation test.

Stereoisomers of alpha-tocopheryl acetate (alpha-TA) have been identified and characterized by means of a recently developed gas-liquid chromatographic technique prior to the determination of their biopotency. It has been shown that totally synthetic all-rac-alpha-TA (dl-alpha-TA) is composed of four pairs of diastereomers (RRS-SSR, RRR-SSS, RSR-SRS, RSS-SRR) in virtually equal proportions. In addition, it has been verified that 2-ambo-alpha-TA (partially synthetic, ex phytol) is an equimolar mixture of RRR-alpha-TA and 2 epi-alpha-TA. Finally, it has been demonstrated that the RRR-alpha-TA (d-alpha-TA) tested was diastereomerically pure. The biopotencies of these alpha-tocopheryl acetate stereoisomers have been evaluated by standardized rat resorption-gestation test. Our first study concerned the comparison of all-rac-alpha-TA with RRR-alpha-TA and resulted in a potency ratio of 1:1.50 or 1:1.48. The first value was derived from the amounts weighed out while the second value was based on the analytically determined alpha-TA content of the stock solutions. Similarly, the comparison of 2-ambo-alpha-TA with RRR-alpha-TA yielded potency ratios of 1:1.32 (amount weighed out) and 1:11.36 (alpha-TA analysed). The influence of the configuration of the side-chain on biopotency has been analysed by a second series of investigations. Comparison of all-rac-alpha-TA with 2-ambo-alpha-TA resulted in a biopotency ratio of 1:1.09 (amount weight out) and 1:1.10 (alpha-TA analysed). However, these slightly higher values for 2-ambo-alpha-TA did not reach statistical significance. These studies demonstrate the validity of the established potency ratio of 1:1.36 for 2-ambo-alpha-TA to RRR-alpha-TA by direct comparison of these compounds. In addition, the experimental ratios for all-rac-alpha-TA to 2-ambo-alpha-TA and for all-rac-alpha-TA to RRR-alph-TA can be grouped into the expression (1:1.10)/(1:1.48) = 1.35. This indirect comparison further supports the accepted value of 1.36 USP Units for 1 mg d-alpha-tocopheryl acetate.

Animals↗
PubMed1980

Chronic asymptomatic HBSAg carriers: histologic abnormalities and diagnostic and prognostic value of serologic markers of the HBV.

Liver histology, the serum "e" antigen system, and DNA-polymerase activity were studied in 68 chronic asymptomatic HBSAg carriers with normal liver chemistries in order to assess the frequency of chronic hepatitis and the diagnostic and prognostic usefulness of serum HBV markers in these subjects. Liver histology was normal in 3 cases, showed nonspecific changes in 46, chronic-persistent hepatitis in 16, and moderate chronic active hepatitis in 3. The "e" antigen and DNA-polymerase activity were positive in 2 and 5 cases, respectively, and were associated with either minimal inflammatory changes or chronic-persistent hepatitis. The "e" antibody was found in 28, evenly distributed among the varios histologic categories; 2 out of 3 patients with chronic active hepatitis carried the "e" antibody. Sixty-four patients have been followed prospectively for 12-30 mo with serial liver tests. During follow-up, 1 patient, with minimal inflammatory changes on liver biopsy and negative for "e" antigen, antibody or DNA-polymerase activity, developed consistently abnormal transaminases, and showed progression to chronic active hepatitis on repeat biopsy. In another patient with chronic-persistent hepatitis, "e" antigen and DNA-polymerase activity reverted to entirely normal serologic status. In our large series, the frequency of chronic hepatitis among HBSAg carriers with normal liver chemistries was somewhat higher than previously reported. In these subjects, the "e" antigen status did not correlate closely with liver histology and did not seem to provide reliable short-term prognostic information.

Adult↗
PubMedDate not supplied

Intrafamilial spread of hepatitis B virus infection. (Role of chronic hepatitis and of the hepatitis B e antigen).

Two hundred and forty household contacts of 85 chronic HBsAg carriers were studied to assess the relationship between liver histology and 'e' antigen or antibody positivity in the index carrier, and evidence of HBV infection within the family. Liver biopsy results were available in 54 index carriers. The prevalence of HBsAg and anti-HBs in the families of 29 carriers with chronic hepatitis and 25 carriers with either a normal liver or minimal inflammatory changes was not significantly different. Serum from 72 index carriers was available for HBeAg and anti-HBe testing. The prevalence of HBsAg and anti-HBs in the families of 5 HBeAg positive carriers, 59 anti-HBs positive subjects, and 8 carriers negative for both HBeAg and anti-HBe was again not significantly different. Infectivity of a carrier thus does not appear to correlate either with histological evidence of liver damage or with the 'e' antigen or antibody positivity of the carrier.

Adult↗
PubMedDate not supplied

Case-control study of hepatitis B virus infection in chronic liver disease and hepatocellular carcinoma.

The prevalence of serum hepatitis B virus markers was studied in three groups of age- and sex-matched patients: a. 31 patients with liver cirrhosis and hepatocellular carcinoma (c-HCC); b. 31 patients with chronic liver disease (CLD) and c. 62 hospitalized control subjects. The overall exposure rate to the hepatitis B virus was 90% in c-HCC, 80% in CLD and 58% in control subjects. The prevalence of hepatitis B surface antigen (HBsAg) was 29%, 13% and 1.6% in the three groups, respectively. The prevalence of hepatitis B surface antibody was significantly lower in c-HCC (9.6%) than CLD (42%) and control subjects (40%). The serological evidence of continuous viral replication (HBsAg positivity or isolated high titre hepatitis B core antibody positivity) was more common in c-HCC (39%) than CLD (12%) and control subjects (1.6%). The prevalence and patterns of aggregation of serum hepatitis B virus markers were similar in the 31 patients with c-HCC and in 11 patients with HCC without concomitant liver cirrhosis (n-HCC). In conclusion, the overall exposure rate to the hepatitis B virus is similar in c-HCC and CLD. However, serological evidence of continuous viral replication is more common in the former group. A defective clearance of the hepatitis B virus in hepatocellular carcinoma is a possible explanation of the phenomenon. The strength of the association between hepatitis B virus infection and hepatocellular carcinoma appears to be similar in c-HCC and n-HCC.

Adult↗
PubMedDate not supplied

Diagnostic value of serum cholylglycine radioimmunoassay in chronic asymptomatic HBsAg carriers.

The correlation between histological liver abnormalities and fasting serum cholylglycine levels was investigated in 75 chronic asymptomatic HBsAg carriers with normal conventional liver tests, to clarify whether serum CG radioimmunoassay could help in distinguishing the carriers with histological liver damage from those with normal histological findings. Mean (+/- SEM) fasting serum CG levels were 11.6 +/- 1.5 micrograms/dl in 56 carriers with normal liver histology, 14.6 +/- 4.2 micrograms/dl in 16 subjects with CPH and 95.6 +/- 54 micrograms/dl in three carriers with CAH. The incidence of abnormal values (greater than 40 micrograms/dl) among carriers with CAH (66%) was significantly higher than in the other two groups (1.8 and 12.5%, respectively). It is concluded that, among chronic asymptomatic HBsAg carriers with normal conventional liver tests, those who show abnormal serum CG levels are likely to have severe histological damage. This justifies the inclusion of CG radioimmunoassay in the routine follow-up of these subjects. The occurrence of false-positive and false-negative results must be considered if the test is used as an aid in the selection of patients for liver biopsy.

Carrier State↗
PubMedDate not supplied

Prevalence of duodenal and jejunal lesions in dermatitis herpetiformis.

Sixty-eight patients with dermatitis herpetiformis underwent jejunal suction biopsies and/or multiple endoscopic duodenal biopsies to evaluate the incidence of small bowel mucosal atrophy and to compare the diagnostic yield of the two methods. Small bowel function tests were also performed to evaluate the extent of functional impairment. Small bowel lesions were observed in 89.4% of jejunal suction biopsies and in 100% of endoscopic duodenal biopsies. Of the 10 patients who underwent both procedures, one had lesions only in the duodenum, one had more severe lesions in the duodenum than in the jejunum, while the remaining 8 patients showed identical lesions at both sites. The 1-h blood d-xylose test after a dose of 5 g proved more sensitive than xylosuria or serum folic acid assay in detecting subclinical malabsorption. Finally, histological features of gluten-sensitive enteropathy can be found in nearly 100% of patients with dermatitis herpetiformis. Upper gastrointestinal endoscopy with duodenal biopsies is at least as sensitive as jejunal suction biopsy in assessing small bowel involvement in dermatitis herpetiformis.

Adolescent↗
PubMedDate not supplied

Electroclinical diagnosis of Angelman syndrome: a study of 7 cases.

The authors describe 7 new cases of Angelman syndrome (AS: 3 males and 4 females) diagnosed on the basis of clinical features (dysmorphic facial features, severe mental retardation with absent speech, peculiar jerky movements, ataxic gait and paroxysms of inappropriate laughter) and neurophysiological findings. Failure to detect deletion of the long arm of chromosome 15 or the absence of epileptic seizure were not considered sufficient to exclude a diagnosis of AS. Feeding problems, developmental delay and early signs of ataxia, especially tremor on handling objects and unstable posture when seated, proved effective as clinical markers for early diagnosis of AS. The EEG patterns characteristic of AS were found within the first 2 years of life (under 18 months in the majority of cases). The authors conclude that AS should be included in differential diagnosis in a child aged under 12 months having cryptogenic psychomotor retardation with prevalent language compromise. Repeat EEG recordings are needed to check for the typical trace, and cytogenetic investigations are mandatory.

Angelman Syndrome↗
PubMedDate not supplied

Ulcerative colitis: specific antibodies against a colonic epithelial Mr 40,000 protein.

A colon tissue-bound disease specific IgG (CCA-IgG) antibody can be eluted from the colonic tissue of patients with ulcerative colitis (UC). CCA-IgG recognizes an Mr 40,000 protein present in both normal and diseased colon. Using an anti-Mr 40,000 murine monoclonal antibody this protein has been localized exclusively in colonic epithelial cells mainly along the baso-lateral domains of plasma membrane. Non-colonic epithelial tissues from 12 different organs including small intestine did not react with the anti-Mr 40,000 monoclonal antibody. The Mr 40,000 protein is present in the RPMI-4788 colon cancer cells but not in HeLa. The antibody dependent cell-mediated cytolysis by UC sera against RPMI-4788 cells was inhibited by anti-Mr 40,000 polyclonal antibody. These findings suggest that CCA-IgG and the Mr 40,000 colonic epithelial protein are involved in an autoimmune reaction and may be important in the pathogenesis of UC.

Antibodies, Monoclonal↗
PubMedDate not supplied

Contribution of immunofluorescence to the identification and characterization of anti-neutrophil cytoplasmic autoantibodies. The role of different fixatives.

OBJECTIVE: To study the sera from selected groups of antineutrophil cytoplasmic antibody (ANCA) positive patients by means of the indirect immunofluorescence test (ANCA-IIF) with different fixatives, in order to better discriminate among the various ANCAs (Ag-specificity and disease associations), especially those for which the antigen targets have not yet been identified. METHODS: Eighty pathological serum samples and 15 normal sera were evaluated. Pathological samples included sera from 30 ulcerative colitis (UC) ANCA positive patients, 30 P-ANCA/myeloperoxidase (MPO-ANCA) positive microscopic polyangiitis (MPA) patients, 10 C-ANCA/proteinase 3 (PR3-ANCA) positive Wegener's granulomatosis (WG) patients, and 10 antinuclear antibody (ANA) positive (ANCA negative) systemic lupus erythematosus (SLE) patients. ANCA were detected by IIF on ethanol, methanol and formalin-fixed granulocytes and by ELISAs specific for MPO, PR3, lactoferrin (LF) and bactericidal/permeability-increasing protein (BPI). Additionally, sera were tested for the presence of antinuclear antibodies on IIF. RESULTS: 96% of serum samples from UC patients, positive by IIF on ethanol-fixed granulocytes, became negative when tested on formalin-fixed neutrophil slides. On the contrary, 95% of sera from vasculitic patients showed a clear diffuse granular cytoplasmic pattern on the same substrate; sera from all 10 SLE patients did not show any reactivity when formalin was used as fixative. On methanol-fixed neutrophils, 100% of UC P-ANCA positive sera were positive with the same pattern versus only 20% of vasculitic P-ANCA positive (MPO positive). Methanol fixation had no effect on PR3-ANCA and ANA positive sera. CONCLUSION: The comparison of IIF patterns of sera tested on different fixed cells may be useful to distinguish vasculitis-related P-ANCA versus ANA and vasculitis-related P-ANCA versus UC-related P-ANCA.

Antibodies, Antineutrophil Cytoplasmic↗