Biomedical subjects
A Quintero
Publications and source records attributed to A Quintero.
p53 protein overexpression and response to induction chemoradiation therapy in patients with locally advanced rectal adenocarcinoma.
BACKGROUND: The association between mutations in the p53 gene and prognosis in colorectal cancer remains controversial. This report evaluates the role of p53 protein to predict the response of neoadjuvant chemoradiation therapy in patients with primary locally advanced rectal adenocarcinoma. METHODS: Between January 1993 and December 1994, 26 patients were seen with locally advanced primary rectal adenocarcinoma, located between 0 and 10 cm from the anal verge, demonstrated clinically and by CT scan. Each received 45 Gy of preoperative radiation therapy (RT) concomitantly with bolus infusion of 5-fluorouracil (5-Fu) (450/mg/m2 on days 1 to 5 and 28 to 33 of RT). Surgery was performed between 4 and 8 weeks later. All the primary tumors were mapped and sliced. The response rate was divided according to the percentage of malignant cells in the rectal wall and perirectal fat. Lymph nodes were studied with the manual or modified clearing technique. p53 mutant status was assessed immunohistochemically from sections of the formalin-fixed, paraffin-embedded pretreatment biopsy and the resected specimen. RESULTS: There were 14 females and 12 males, with a mean age of 54 years. All received the scheduled treatment. An abdominoperineal resection (n = 10), low anterior resection (n = 10), and pelvic exenteration (n = 6) were performed. The stages of tumors were as follows: no residual tumor (n = 4); T2 (n = 6); T3-4 (N = 9); and T3-4, N1,2 (n = 7). Fourteen specimens (54%) had mutated p53, and 10 (71%) had >50% of residual tumor, whereas only two (17%) of the specimens with normal p53 had >50% of residual tumor (P = .018). Eight of the 10 low anterior resections were performed in patients whose specimens expressed normal p53. CONCLUSION: Our results suggest that the determination of p53 is a factor in predicting tumor response in patients who undergo preoperative chemoradiation therapy for rectal adenocarcinoma.
Antitumoral activity of new pyrimidine derivatives of sesquiterpene lactones.
Sesquiterpene lactones display a wide variety of biological effects such as antiviral, anti-inflammatory and cytotoxic activity. In previous studies some derivatives of sesquiterpene lactones were prepared to be tested as antiviral and/or cytoxic agents. In the present report we describe the effects of seven modified sesquiterpene lactones on the proliferation of several cancer cell lines. We demonstrated antitumoral activity of two of them: III (JLNZ-106) and IV (EDAG-IV-Sme) in HeLa, C-33, CALO, INBL, VIPA, SW480, SW620, MCF-7 and CHO cancer cell lines. Compounds III (JLNZ-106) and IV (EDAG-IV-Sme-IV) presented cytotoxic activity (IC50) by inhibiting the incorporation of (14)C-thymidine to DNA. These experiments suggest that derivatives III and IV should inhibit DNA replication in cancer cell lines.
[Antibiotypes of bacterial strains isolated from patients at the intensive care units].
The indiscriminate use of antibiotics in intensive care units has permitted the selection of multiple resistant bacterial strains in the hospital setting. Antibiograms present the sensitivity or resistance of these strains to drugs in current use. In this study, 100 bacterial strains were isolated from patients on medical and surgical ICU wards. The strains were identified by API-20E and sensitivity testing was performed by the E-test procedure. MIC were further analyzed with the WHONET software wich permits the identification of antibiotypes. Acinetobacter anitratus, Pseudomona aeruginosa and Enterobacter cloacae were the most resistant strains. Nine antibiotypes were determinated for A. Anitratus. Predominant strain presented antibiotypes with multiple resistance to ten antibiotics. P. aeruginosa presented 10 antibiotypes, the predominant one being CTX, CRO, CTX. Antibiotype determination allows phenotypic identification or resistance patterns in particular species as well as facilitates follow up and recognition of its epidemiological distribution.
Immunoregulation with methisoprinol in Sjögren's syndrome.
In this work, we studied the therapeutic clinical efficacy and the immunoregulating effect of methisoprinol in 4 cases of primary SS and one case of secondary SS. After 12 weeks of treatment, no significant clinical improvement was detected in the glandular histology, in Schirmer's test and sialography. On the other hand, we have observed the following alterations: immunological changes characterized by an increase in the total population of T-lymphocytes (OKT3), a normalization and thereby a diminution in IgM, an increase in T-helper subpopulation (OKT4) in four cases and in T-suppressor subpopulation in one case. A noticeable fact was the best immunological response of the patient showing a negative histology, a functional alteration of the parotid and a short evolution of the syndrome. These findings support the hypothesis that methisoprinol can be an efficient coadjuvant in the treatment of primary Sjögren's syndrome in early stages when there is only functional alteration but no glandular atrophy.
Immunotherapy with standard bacterial and bacterial ribosomal antigens in childhood bronchial asthma.
UNLABELLED: In this study we compared the therapeutic effectiveness of a lyophilized bacterial vaccine (LBV) with that of a vaccine prepared from bacterial ribosomal antigens (ARB) in 150 children with bacterial bronchial asthma. The immunological response of the patients was assessed clinically at 6 months, 1 year and 3 years, by determining the intensity and frequency of the bronchospasm. The serum immunoglobulin levels, the only immunologic parametres studied, were determined at basal conditions and following immunotherapy. CLINICAL RESULTS: after 360 days we detected a better clinical response in those patients who received the ribosomal vaccine (ARB), whereas after 3 years there was no difference in the clinical response between this group of patients and the group who received the bacterial vaccine (LBV). Immunological results: we were not able to show a statistically significant increase in immunoglobulin levels during the three years of immunotherapy with the two vaccines. However, those patients who possessed a deficit in IgG displayed a statistically significant increase in IgG levels after 360 days (t = 3.58, p less than 0.01), and an even greater increase after 1080 days (t = 7.86, p less than 0.001), of treatment with the standard bacterial vaccine. The ribosomal vaccine produced a significant increase in IgG levels (t = 9.59, p less than 0.001) after 1080 days also in patients with a deficit in IgG. In patients with a previous deficit in IgA we did not observe an increase in serum IgA levels during immunotherapy with the bacterial vaccine, but with the ribosomal vaccine these patients displayed significantly higher levels of IgA (t = 13.09, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)
[Massive thrombosis of the left atrium and severe mitral stenosis in a patient with normal wedge pressure (author's transl)].
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[Obtaining viable protoplasts of tomato leaves (Lycopersicon esculentum)].
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