The effect of peritoneal dialysis with alkaline dialysate in peritonitis carcinomatosis: an experimental study in mice.

OBJECTIVE: The aim of this study was to neutralize acidic pH using an alkaline dialysate for continuous ambulatory peritoneal dialysis (CAPD) in mice with peritoneal carcinomatosis (PC) and to investigate the change of the pH level in the acidic fluid along with its effects on liver oxidative stress, liver and kidney histopathology and the lifespan of the body. MATERIALS AND METHODS: A total of 38 mice were randomly divided into 4 groups.PC development was inhibited by intraperitoneal injection of Ehrlich tumor cells in all mice in each group. RESULTS: In the group-1 receiving CAPD, the pH levels of acidic liquid were higher; and the levels of liver TBARS were lower with higher reduced glutathione levels. Histopathological damage in group-1 was less than in group-2. In Group 3 receiving CAPD, the average lifespan extended by 10.4%. The average lifespan extended by 26.1%. CONCLUSION: This study indicated that applying CAPD with alkaline dialysate in PC contributed to the neutralization of acidosis of the intraperitoneal acid structure;had favorable effects on oxidative stress markers in liver tissue; prevented histopathological injury in liver and kidney tissues, and extended the life span of the body in mice. As this is a simple, inexpensive, and easily available method, larger studies are warranted to evaluate its effects.

Heavy Metals in the Blue Crab (Callinectes sapidus) in Mersin Bay, Turkey.

The concentrations of four metals (copper, cadmium, zinc and lead) were quantified in blue crabs (Callinectes sapidus) tissues collected in January, April, June and September at two stations in Mersin Bay, northeastern Mediterranean Sea, using ICP-MS. The metal concentrations in crabs from the two stations differed significantly. The hepatopancreas was the major organ accumulating metals, followed by gill and muscle tissues. Except for lead, the highest concentrations of metals were measured in the hepatopancreas. The hepatopancreas had higher concentrations of all heavy metals (Cu 321.1 ± 4.30; Zn 182.2 ± 3.40; Cd 48.2 ± 2.00) compared to gill (Cu 90.2 ± 1.35; Zn 104.3 ± 2.30; Cd 22.3 ± 3.40) and muscle (Cu 19.1 ± 1.10; Zn 55.1 ± 3.25; Cd 2.5 ± 0.20). Among the metals analyzed, Cu, Zn and Pb were the most abundant in the different tissues while Cd was the least abundant in C. sapidus. Seasonality in the levels of the four metals was determined.The highest concentrations of all metals were observed in the June (Zn 55.1 ± 3.25; Cu 19.1 ± 1.10; Cd 2.5 ± 0.20; Pb 5.1 ± 0.18) compared to all other months (Zn 34.1 ± 3.23; Cu 11.1 ± 1.15; Cd 0.9 ± 0.20; Pb 3.1 ± 0.21).

QSARs of some novel isosteric heterocyclics with antifungal activity.

QSAR analysis of a set of previously synthesized 2,5,6-trisubstituted benzoxazole, benzimidazole and 2-substituted oxazolo(4,5-b)pyridine derivatives tested for growth inhibitory activity against Candida albicans, was performed by using the computer-assisted multiple regression procedure. The activity contributions for either heterocyclic ring systems or substituent effects of these compounds were determined from the correlation equation and the predictions for the lead optimization were described. The resulting QSAR revealed that the oxazolo(4,5-b)pyridine ring system with the substitution of a benzyl moiety at position 2 was the most favourable structure among the heterocyclic nuclei. Moreover, the fifth position in the fused ring system is found more significant than the other positions in improving the activity.

Synthesis and antimicrobial activity of some novel 2,5- and/or 6-substituted benzoxazole and benzimidazole derivatives.

A new series of 2,5- and/or 6-substituted benzoxazoles (7a-f), benzimidazoles (8a-g) holding cyclohexyl or cyclopentyl moieties at position 2 and 5- or 6-substituted-2-cyclohexylaminomethylbenzoxazoles (9a, b) was synthesized in order to determine their antimicrobial activities and feasible structure-activity relationships. The synthesized compounds were tested in vitro against three Gram-positive, two Gram-negative bacteria and the yeast Candida albicans in comparison with several control drugs. Microbiological results showed that the synthesized compounds were possessing a broad spectrum of antibacterial activity against the tested microorganisms. 5-Chloro-2-(2-cyclohexylethyl)benzimidazole (8g) was found as the most active compound against the screened Gram-positive bacteria strains at a minimum inhibitory concentration (MIC) value of 12.5 microg/ml. However, it exhibited lower antibacterial potency than the compared control drugs. On the other side, compounds 7-9 indicated significant antibacterial activity against the Gram-negative enterobacter Pseudomonas aeruginosa having MIC values of 50 microg/ml, providing either the same effect as tetracycline or higher activity than streptomycin, but showing less potency than the compared control drug gentamycin. Moreover, the synthesized compounds also possessed antimycotic activity against the yeast C. albicans showing MIC values between 25-50 microg/ml.

Synthesis and microbiological activity of some novel 5- or 6-methyl-2-(2,4-disubstituted phenyl) benzoxazole derivatives.

The synthesis of a new series of 5-or 6-methyl-2-(2,4-disubstituted phenyl) benzoxazoles (4, 5) is described in order to determine their antimicrobial activities and feasible structure-activity relationships. The synthesized compounds were tested in vitro against three Gram-positive bacteria, three Gram-negative bacteria and the yeast Candida albicans, in comparison with several control drugs. Microbiological results exhibited that the synthesized compounds possess a broad spectrum of antibacterial activity against the tested microorganisms. The compounds 4b and 4c indicated some antibacterial activity against Staphylococcus aureus having a minimum inhibitory concentration (MIC) of 12.5 micrograms/ml. Moreover, the compound 5a revealed a significant antibacterial activity against the enterobacter Pseudomonas aeruginosa showing a MIC value of 25 micrograms/ml, i.e. more potent than the control drugs tetracycline and streptomycin. For the antimycotic activity against the yeast C. albicans, the derivative 4c was found to be more active than the other synthesized compounds with a MIC value of 12.5 micrograms/ml, but one-fold less potent than the control drugs oxiconazole and haloprogin.

Synthesis and structure-activity relationships of some 2,5-disubstituted benzoxazoles and benzimidazoles as antimicrobial agents.

The synthesis of a new series of 2,5-disubstitutedbenzoxazoles 5a-e, and 2,5-disubstitutedbenzimidazoles 6a-h are described in order to determine their antimicrobial activities and feasible structure-activity relationships (SAR). The synthesized compounds were tested in vitro against 3 Gram-positive, 3 Gram-negative, bacteria and a fungus Candida albicans. 5c, and 5e were found most active than the others against Bacillus subtilis at a MIC value of 3.12 micrograms/ml and the compounds 5e, 6a and 6e indicated significant antibacterial activity against the enterobacter Pseudomonas aeruginosae. 5a, 5c, 5d and 6d also exhibited antimycotic activity against C. albicans. The antibacterial and antimycotic activities of 5-6 are compared with several control drugs.

Synthesis and microbiological activity of 5(or 6)-methyl-2-substituted benzoxazole and benzimidazole derivatives.

The synthesis and microbiological activity of a new series of 5(or 6)-methyl-2-substituted benzoxazoles (IVa-n) and benzimidazoles (Va-h) were described. The in vitro microbiological activity of the compounds was determined against gram-positive, gram-negative bacteria and the yeast Candida albicans in comparison to reference drugs. Microbiological results indicated that the derivatives possessed a broad spectrum of activity against the tested microorganisms and the compounds IVa-g, IVi-k, IVn, Vb-c and Vh showed significant activity against Pseudomonas aeruginosa having MIC values of 25 micrograms/ml, providing higher potencies than the reference drugs tetracycline and streptomycin. Moreover, the derivative 5-methyl-2-(p-chlorobenzyl)benzoazole (IVb) possessed the same potency against Candida albicans as the reference drugs oxiconazole and haloprogin having a MIC value of 6.25 mg/ml. However, none of the derivatives showed a better spectrum of activity than the reference drugs.

Synthesis and microbiological activity of some novel N-(2-hydroxyl-5-substitutedphenyl)benzacetamides, phenoxyacetamides and thiophenoxyacetamides as the possible metabolites of antimicrobial active benzoxazoles.

Synthesis of some novel N-(2-hydroxyl-5-substitutedphenyl)benzacetamides, phenoxyacetamides and thiophenoxyacetamides (5a-k) were described in order to determine their in vitro antimicrobial activity against 3 Gram-positive, 3 Gram-negative bacteria and the fungus Candida albicans comparing with several control drugs. The derivative 5e was found active at a MIC value of 25 micrograms/ml against the whole tested Gram-positive bacteria strains and the Gram-negative microorganism Klebsiella pneumoniae. Moreover, the synthesized compounds 5a-k exhibited significant antibacterial activity against the enterobacter Pseudomonas aureginosae when compared to the control drugs. For the antifungal avtivity against C. albicans, the compound 5k was found more active than the other synthesized derivatives. On the other hand, the antimicrobial activity of some of these acetamide derivatives (5c, 5d, 5e, 5j and 5k) which are the possible metabolites of benzoxazoles, were also compared with their cyclic analogues 6-10. However, most of the MIC values of the benzoxazole derivatives provided better activity than the compared acetamides, while some others of the acetamide derivatives possessed either one fold improved (5d, 5e and 5j) or the same potency (5c, 5d, 5e, 5j and 5k) against the tested microorganisms.