Performance of immobilized bacterial alpha-amylases in methyltriethoxsilane / tetraetoxysilane sol-gel matrices

The large number of studies related to the field of biomolecules encapsulation in sol-gel hosts clearly indicates that this approach can be considered as a powerful alternative to traditional encapsulation procedures involving biopolymer hosts. In this study, α-amylase was immobilized, by using the sol-gel technique, in silica particles obtained from hydrolysis and polycondensation of tetraethoxysilane (TEOS) and a mixture of methyltriethoxysilane (MTES) and tetraethoxysilane. The influence of the pH and temperature of free and immobilized α-amylase were compared. It was shown that the relative activities of immobilized enzymes are higher than those of free enzymes over broader pH and temperature ranges. The Michaelis constant and the maximum rate of starch hydrolysis reaction were calculated by fitting the experimental data to the Michaelis-Menten equation. It was found that KM and Vmax values of the immobilized enzyme were smaller than those of the free enzyme

Adjuvant treatment for elderly patients with colon cancer. An observational study

Background: Adjuvant. 5-fluoruracil-based chemotherapysignificantly reduces mortality in. patients with: stage II-III colon cancer, but is less prescribed with rising age. In this study we were interested in the pattern of adjuvant treatment and possible effects on survival among elderly patients. Patients and methods: From January to December 2004, 63 questionnaires on the management of stage II-III resected colon cancer patients aged over 70 years, collected from 10 Italian Centres, were retrospectively examined. Determinants of receipt of adjuvant chemotherapy and their relation to survival were considered. Results: The proportion of elderly patients receiving adjuvant chemotherapy was 79.4%, distinct of age, gender, educational level and comorbidities. Grade 3-4 toxicities were the following: haematological in 4 (8.5.%) patients, mucositis in 4 (8.5%), diarrhoea in 2 (4.2%) and nausea in 1 (2.1%). The disease-free survival (DFS) and overall survival (OS) at two years were 79.9% and 95.6%, respectively. Due to the paucity of events, the impact of prognostic factors (patient's age and comorbidity, tumour stage and grade) on DFS and OS could not be assessed. Conclusion: An increasing proportion of elderly patients with colon cancer may be treated with a tolerability and OS similar to those observed in the younger population. Development of age-based guidelines and increased awareness of both physicians and patients through education is important to prevent undertreatment of those elderly patients who are eligible for chemotherapy

SYNTHESIS AND EFFECTS OF SOME NEW 2-ARYL-THIAZOLE AMMONIUM SALTS ON ISOLATED ILEUM MOTILITY

Quaternary ammonium compounds are considered among the substances which can influence the contractility of smooth muscles from the digestive tract, acting via cholinergic mechanisms. Based on structural considerations, we synthesized twelve new compounds, derivatives of 2-aryl-thiazole, being substituted in the 2 and 4 positions. In order to elucidate the structure of the obtained compounds, MS determinations and 1 H-NMR spectra were realized. The effect on the smooth muscles was tested using the guinea pig isolated ileum experimental model. The obtained results showed that the contractile effects or the antispasmodic activity of the compounds are influenced by the nature of the substituent in the 4 position, and the intensity of the effect is related to the type of substituent on the phenyl, from the 2 position of the thiazolic nucleus

SYNTHESIS AND IN VITRO ANTICANCER ACTIVITY OF NEW THIADIAZOLINES AND THIAZOLINONES CONTAINING A CHROMENYL SCAFFOLD

A series of 14 derivatives of chromenyl-dihydro-thiadiazole and chromenyl-methylenethiazolin-4-one were synthesized and screened (using the MTT colorimetric assay) for their in vitro growth inhibition capacity in six human cancer cell lines. Three cell lines displayed various levels of resistance to pro-apoptotic stimuli, while two cell lines were sensitive to pro-apoptotic stimuli. Structure Activity Relationship (SAR) analyses indicate that, of the two compound series that were investigated, chromenyl-thiadiazolines displayed higher in vitro anticancer activity than the thiazolinone derivatives. With respect to the thiadiazoline derivatives (3a-l compounds), the substitution of the exocyclic amine with a substituted-phenyl moiety increased the in vitro growth inhibition of cancer cells, and the 3-trifluoromethyl-phenyl-derivatives (3h, 3l) displayed the highest antiproliferative activity. In addition, compounds 3h, 3k and 3l overcame the intrinsic resistance of cancer cells to pro-apoptotic stimuli by induction of either cytostatic (3h, 3l) or cytotoxic (3k) effects, which was determined by quantitative videomicroscopy

Palliative treatment for elderly patients with colon cancer in ten Italian medical oncology units

Background: Palliative chemotherapy significantly reduces mortality in patients with stage IV colon cancer, but is less prescribed with rising age. In this paper, we highlight the pattern of palliative treatment and possible effects on survival among elderly patients. Patients and Methods: From January to December 2004, 78 files on the management of stage IV colorectal cancer (CRC) patients over 70 years, collected from 10 Italian Centres, were retrospectively examined. Determinants of receipt of palliative chemotherapy and their relation to toxicity and survival were considered. Results: The proportion of elderly patients receiving first-line palliative chemotherapy was 98.7% and it was evaluated according to age, gender, educational level and comorbidities; patients receiving second-line therapy comprised 47.4%, those receiving third-line therapy 14.1% and those treated with a fourth-line therapy totalled 2.6%. Forty-one percent of patients received best supportive care (BSC) alone. Conclusion: In Italy, a proportion of elderly patients with metastatic chemonaive CRC are usually treated with a tolerability and overall survival similar to those for the younger population. Among progressive patients after second-line therapy, 45.8% usually undergo third line therapy; the remaining 54.2% undergo BSC