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Biomedical subjects

E Villa

Publications and source records attributed to E Villa.

At least 19 recordsLinked to original sources
PubMed1992

An anti-doxorubicin monoclonal antibody modulates kinetic and dynamic characteristics of the drug.

A monoclonal antibody (MAb) directed against doxorubicin (DXR), denominated MAD II, was found to exert an antidotal action by modulating the kinetic and dynamic characteristics of the drug. In vitro, MAD II has been found to reduce the cytotoxicity of DXR and the drug uptake on spleen lymphocytes more efficiently than on tumor cells (P388 leukemia cells). In vivo, the anti-DXR MAb modified the drug distribution; the drug uptake was found to be reduced in the intestine and myocardial tissues and increased in the tumor, liver and spleen. In mice treated with DXR, the administration of anti-DXR MAb exerted an antidotal activity which was proved by the reduction in body-weight loss and mortality. In contrast, the therapeutic efficacy of the drug in P388-tumor-bearing mice was not influenced by the anti-DXR MAb.

Animals↗
PubMed1992

Immunogenicity and safety of a recombinant hepatitis B vaccine produced in mammalian cells and containing the S and the preS2.

A group of 273 health care workers, at risk of HBV infection, underwent vaccination with recombinant HBsAg produced in mammalian cells and containing protein sequences coded by both the S and pre-S2 regions (Genhevac B). Preliminary results show that a very early pre-S2 response occurred which may be useful in post-exposure prophylaxis. This observation, in addition to reduced influence by the vaccination protocol, provides grounds for optimism in spite of the fact that the efficiency spectrum of this vaccine was not superior to that of recombinant vaccines produced in yeast.

Adolescent↗
PubMed1992

Presence of HCV RNA in serum of asymptomatic blood donors involved in post-transfusion hepatitis (PTH).

To study the causes of residual posttransfusion hepatitis, serum from implicated donors was tested by PCR for the presence of HCV RNA. Of 20 anti HCV negative donors, 4 were HCV RNA positive and thus, infective. The results suggest that higher-level investigations are necessary for prospective donors who present blood enzyme abnormalities or other questionable characteristics.

Alanine Transaminase↗
PubMed1992

Characterization of two monoclonal antibodies directed against the 67 kDa high affinity laminin receptor and application for the study of breast carcinoma progression.

Two monoclonal antibodies (mAbs), designated MLuC5 and MLuC6, were produced against a human small cell lung carcinoma cell line. They were found to exhibit a superimposable reactivity on different cell lines and on platelets. Moreover, they both immunoprecipitated a 67 kDa molecule from the membrane of the reference target cells. Immunodepletion and cross-inhibition tests indicated that the two mAbs recognize two epitopes closely localized on the same molecule. The MLuC5 mAb was further characterized for its reactivity on platelets. Immunoprecipitation and ELISA assays demonstrate that this mAb recognizes the 67 kDa high affinity laminin receptor. MLuC5 reactivity was evaluated by immunohistochemistry on a variety of normal and tumor tissues, in particular breast specimens including normal epithelium, dysplastic lesions, in situ carcinomas, invasive primary carcinomas and distant metastases. The laminin receptor was found to be strongly expressed in 50% of the infiltrating carcinomas, whereas in situ carcinomas and benign lesions, as well as the normal mammary epithelium, were only weakly and focally positive. In metastatic lesions MLuC5 reactivity was only found in 11% of the samples tested, independently of the site of origin of the lesion.

Animals↗
PubMed1992

Hepatitis C virus testing in primary biliary cirrhosis.

We retrospectively investigated anti-HCV prevalence in a series of 160 consecutive patients with primary biliary cirrhosis who presented between 1980 and 1989. Of these, 19 (12%) were positive for anti-HCV by C-100 ELISA. Serum IgG levels were significantly higher in anti-HCV-positive patients and correlated to optical density values. A serum sample was again collected from all the patients from the same series who were seen in 1990 for follow-up, after a median period of 32 months. Anti-HCV positivity was found to be substantially unchanged in this subgroup of patients when the freshly drawn blood samples were retested with C-100 ELISA, while it increased from 10% to 17% when second generation ELISA was used. Three of the C-100 ELISA positive samples were C-100 RIBA reactive, and six of the second generation ELISA positive samples were 4-RIBA reactive. The HCV genome was not detected in any of the seven anti-HCV C-100 ELISA and second generation ELISA positive sera which were studied by polymerase chain reaction, including four cases confirmed by 4-RIBA. Life expectancy, as determined by survival analysis, did not differ significantly between anti-HCV-positive and -negative patients. These findings suggest that anti-HCV positivity does not influence the clinical presentation and course of primary biliary cirrhosis.

Adult↗
PubMed1992

Hepatitis C virus infection, HBsAg carrier state and hepatocellular carcinoma: relative risk and population attributable risk from a case-control study in Italy.

In 1990, a case-control study was conducted in Italy to investigate the possible association between HCV infection and hepatocellular carcinoma (HCC). Serum samples from 65 subjects with newly diagnosed hepatocellular carcinoma and 99 hospital control subjects were tested for the presence of anti-HCV by second-generation ELISA test; positive sera were assayed by RIBA anti-HCV second-generation test. In addition, samples were tested for hepatitis B surface antigen (HBsAg), antibodies to the hepatitis B core antigen (anti-HBc), and antibodies to HBsAg (anti-HBs). The presence of HCV and/or HBsAg serologic markers was significantly associated with hepatocellular carcinoma risk: the relative risk (RR) of HCC was 21.3 (95% CI = 8.8-51.5) for anti-HCV positivity in the absence of HBsAg; the relative risk of HCC was 13.3 (95% CI = 5.5-32.2) for the presence of HBsAg in the absence of anti-HCV. A higher risk (77.0) was observed when both markers were present. These findings indicate that HCV and HBsAg are independent risk factors for HCC. The results of multivariate analysis showed that the adjusted RR linking anti-HCV and HCC was 26.9 (95% CI = 9.9-72.5), the adjusted RR linking HBsAg and HCC was 11.4 (95% CI = 3.1-41.4), whereas no association (RR 1.5; 95% CI = 0.6-3.6) was found to link HCC with anti-HBc and/or anti-HBs positivity. Through the computation of population attributable risk we estimate that 25% of HCC cases occurring in Italy could be attributed to anti-HCV positivity alone and 20% to HBsAg carrier state alone.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Three-step monoclonal antibody tumor targeting in carcinoembryonic antigen-positive patients.

We describe a method to postlabel, in vivo, biotinylated monoclonal antibodies pretargeted onto tumor deposits when most of the non-tumor-bound antibodies have already been cleared as avidin-bound complexes. The application of this principle to tumor detection by immunoscintigraphy was tested in 20 patients with histologically documented cancer and increased circulating carcinoembryonic antigen levels. One mg of biotinylated anti-carcinoembryonic antigen monoclonal antibody (FO23C5) was administered i.v. (first step). After 3 days, 4-6 mg of cold avidin were injected i.v. (second step), followed 48 h later by 0.2-0.3 mg of a biotin derivative labeled with 111In (2-3 mCi) (third step). No evidence of toxicity was observed. Whole body radioactivity distribution was measured in five patients at various intervals postinjection by the conjugate counting technique. Tumors and metastases were detected in 18 of 19 patients (the remaining patient was a true negative) within 3 h after administration of 111In-biotin by planar or single photon emission tomography imaging. At the time of imaging, tumor/blood pool ratio was 5.5 +/- 3.2, and tumor/liver ratio was 6.7 +/- 3.9. Blood clearance of 111In-biotin was multiexponential, with the fast component having a t1/2 of 5 +/- 3 min. Urinary excretion of radioactivity over 3 h was 63.5 +/- 4.9% of the injected dose. Radioactivity at 3 h was 6.5 +/- 1.8% in blood, 1.6 +/- 0.3% in the kidney, and 2.4 +/- 0.6% in the liver. This approach represents an improvement in immunoscintigraphic techniques for tumor localization. The potential use for radioimmunotherapy is discussed.

Antibodies, Monoclonal↗
PubMed1991

Conserved core protein sequences in hepatitis B virus infected patients without anti-HBc.

The absence of detectable anti-HBc antibodies in some hepatitis B virus (HBV) infected patients may be due to altered core-protein (HBc) sequences. To investigate this possibility we sequenced the pre-C/C-region of HBV isolated from 12 juvenile cancer patients who incurred a nosocomial infection of HBV during chemotherapy but did not develop anti-HBc antibodies or acute cytolytic episodes. The sequences demonstrated the highest sequence homology to the pre-C/C region of a previously cloned HBV genome (subtype ayw) and no deletions or striking mutations were detected. Up to 7 years after infection almost all the survivors developed low titers of anti-HBc antibodies but no clinical signs of hepatic damage. These results suggest that chemotherapy may induce a tolerance status to HBcAg, the most immunogenic HBV protein.

Base Sequence↗
PubMed1991

HCV RNA in serum of asymptomatic blood donors involved in post-transfusion hepatitis (PTH).

A group of blood donors involved in post-transfusion hepatitis was investigated for the presence of the anti-HCV antibody and of HCV RNA as a more direct infection marker. RNA was extracted from serum, reverse transcribed and amplified using primers which belonged to the non structural region. The amplified product of the PCR reaction was 582 base pairs. Seven (25.9%) of the 27 blood donors examined were found anti-HCV-positive by ELISA; five (71.4%) of these were HCV RNA positive. Among the 20 anti-HCV-negative blood donors, four (20.0%) were HCV RNA positive. ALT levels were below 45 UI/l in 18 donors, while the other nine had ALTs over the limit accepted for transfusion. The anti-HCV-negative HCV RNA-positive blood donors had normal ALTs. Our study offers a direct explanation for the substantial proportion of residual cases of anti-HCV-positive post-transfusion hepatitis and suggests the necessity of creating a register of blood donors who have at some time presented blood enzyme abnormalities and for whom second level investigations such as HCV RNA should be used.

Base Sequence↗
PubMed1991

Antibodies to hepatitis C virus in patients with hepatocellular carcinoma.

To study the potential relationship between the hepatitis C virus (HCV), the major etiologic agent of parenterally transmitted non-A, non-B hepatitis, and the development of hepatocellular carcinoma (HCC), we tested the presence of anti-HCV antibodies in sera from a large panel of HCC patients of different racial and geographical origins. Anti-HCV antibodies were detected in 82 out of 114 (71.9%) HBsAg-negative HCC patients and in 15 out of 53 (28.3%) HBsAg-positive patients. No significant difference in the prevalence of anti-HCV antibodies was found in the HBsAg-negative HCC patients when they were divided according to presence of anti-HBs and/or anti-HBc antibodies, or absence of all hepatitis B virus (HBV) serological markers. The prevalence of anti-HCV antibodies was similar in HCC patients of Caucasian and African origin. No differences were noted when the patients were grouped according to sex. The mechanisms by which HCV might contribute to the development of HCC need to be further investigated. As for HBV infection, the necro-inflammation associated with HCV infection may induce cirrhosis, regeneration and eventually malignant transformation. The finding that few anti-HCV patients had HCC which is not superimposed on cirrhosis suggests that HCV could, however, exert some direct effect on the development of HCC.

Adolescent↗
PubMed1991

Systemic preoperative chemotherapy with cisplatin, methotrexate and vinblastine for locally advanced bladder cancer: local tumor response and early followup results.

A total of 44 patients with infiltrating, locally advanced bladder cancer (stages T 3a-b, T 4a-b and N+/N0) were treated with the systemic chemotherapy regimen of cisplatin, methotrexate and vinblastine (CMV) in the neoadjuvant setting, of whom 39 were evaluable for response. After planned radical cystectomy and 2 to 3 cycles of chemotherapy no tumor was found on the pathological specimen of 4 patients (10%), the tumor was downstaged in 19 (49%) and no change was observed in 16 (41%). Toxicity included leukopenia in 29 patients (66%), 1 of whom died of granulocytopenic sepsis, nausea and vomiting in 39 (89%) and mild to moderate mucositis in 18 (41%). Median followup is 12 months with a range of 6 to 39 months. Of 32 patients followed for longer than 6 months 6 (19%) experienced progression or recurrence of disease. We conclude that preoperative CMV chemotherapy is effective in inducing downstaging of the tumor, although systemic toxicity limits its use to cautiously selected patients.

Adult↗
PubMed1991

[Analysis of the results of 264 cases of small breast carcinoma treated with conservative surgery and radiotherapy].

From January 1981 to December 1987, 264 patients affected with small breast cancers were treated with quadrantectomy plus axillary dissection and radiation therapy on the breast remnant (QUART). Mean age of the patients was 53 years; 124 of them were less than or equal to 50 years old (46.9%); 85 had axillary nodal metastases (32.2%), and 58 presented a primary tumor with pathologic size (greater than 2 cm) (22.9%). Overall actuarial survival at 3 and 7 years, according to the Kaplan and Meyer method, was 95.5% and 85.3%, respectively; NED survival was 85.9% and 77.4%. Twenty patients died (19 of cancer). Local relapses were 6 (2.3% on the whole and 13.3% on the whole of recurrences observed at follow-up). Local relapses were central in the quadrantectomy scar in 4/6 patients. Histology and site of the primary lesion were not correlated with a major risk of local failure. Isolated recurrences in the breast did not worsen survival. Nodal failures were 5 (1.9% on the whole of cases; 11.1% on the whole of failures). Our study confirms the role of QUART as an effective and reliable method in the treatment of small breast carcinomas.

Adult↗
PubMed1990

Sequential and synchronous chemo-radiotherapy in the management of locally advanced carcinoma of the head and neck.

Thirty-nine consecutive patients with stage III-IV squamous cell carcinoma of the head and neck entered a pilot study of sequential and synchronous chemo-radiotherapy. The study was planned as follows: two cycles of induction chemotherapy (MTX, BLM, DDP) followed by radical radiotherapy (66 Gy) with synchronous weekly administration of DDP (20 mg/m2) as a radiosensitizer. Out of the 39 patients evaluable for induction chemotherapy 25 (64%) achieved partial or complete response. Two patients underwent radical surgery after induction chemotherapy and 3 patients died of treatment. Out of the remaining 34 patients, 25 were untreated and 9 presented recurrence after primary surgery. Grade 4 mucositis was the major side effect of concurrent chemo-radiotherapy. Local control after synchronous therapy was obtained in 11 (44%) previously untreated patients and only in 1 (11%) patient of the surgically pre-treated group. At the time of the analysis 11 patients were alive, 8 of them free from disease (4 after salvage surgery). Actuarial 2-year survival for previously untreated patients was 33% and 24% for all the patients. This survival is not significantly different (log rank test) from that of a similar group of 24 patients treated at the same institution with radiotherapy alone. The important toxicity of the induction chemotherapy regimen and the poor 2-year survival do not show any benefit from such a combined approach in locally advanced head and neck carcinoma. Nevertheless, despite our disappointing results many data in the literature suggest a role for chemotherapy-based treatments of locally advanced head and neck cancer. Further controlled randomized studies are required to better define the place of chemotherapy in the multi-modality management of stage III-IV head and neck cancer.

Adult↗