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Biomedical subjects

E Ismail

Publications and source records attributed to E Ismail.

7 recordsLinked to original sources
PubMed2000

Effects of

Effects of cetyltrimethylammonium bromide (CTABr) micelles on second-order rate constants (k(n)(obs)) for nucleophilic reactions of amines (piperidine and n-butylamine) with ionized phenyl salicylate (PS(-)) reveal a nonlinear decrease with the increase in [D(n)] (where [D(n)] = [CTABr](T) - cmc) at a constant [NaBr] and 35 degrees C. The observed data, at a constant [NaBr], fit reasonably well to a pseudophase model of micelles, and such a data fit gives kinetic parameters such as CTABr micellar binding canstant (K(S)) of PS(-). The effect of [NaBr] upon K(S) is explained with the empirical relationship K(S) = K(S)(0)/(1 + psi[NaBr]), where psi is an empirical parameter.

Journal Article↗
PubMed2000

Carbonyl reductase: a novel metastasis-modulating function.

To explore reasons for differences in the malignancy of tumors, we have compared two cell lines derived from a mouse lung adenocarcinoma cell line that differ 10-fold in their capacity to form lung metastases from s.c. primary tumors or after i.v. injection. One mRNA encoding carbonyl reductase was identified at a relatively high abundance in the subline with low metastatic capacity but was not detectable in the highly metastatic subline. Transfection of the former subline with a plasmid construct expressing antisense carbonyl reductase rendered the cells highly metastatic. Conversely, the capacity of the highly metastatic cells to metastasize was markedly reduced after transfection with a construct expressing carbonyl reductase. We also found that human prostate cancers show loss of carbonyl reductase expression compared with normal prostate epithelia. These data suggest that carbonyl reductase has an important function in modifying the metastatic behavior of malignant tumors.

Adenocarcinoma↗
PubMed1999

Effects of Nonionic, Cationic, and Mixed Nonionic-Cationic Surfactants on the Acid-Base Behavior of Phenyl Salicylate.

The effects of Brij 35 micelles, CTABr micelles, and mixed Brij 35-CTABr micelles on the acid-base behavior of phenyl salicylate (PST) have been studied in aqueous solution containing 2% v/v acetonitrile. The apparent pK(b) (pK(app)(b)) of PST is decreased by 1.5 pK units with the increase in [Brij 35] from 0 to 0.02 M which is attributed to micellar medium effect. The values of pK(app)(b) remain almost independent of [CTABr] within its range 0.01-0.03 M. The increase in [CTABr] from 0 to 0.03 M in aqueous solution containing 0.02 M Brij 35 has not resulted in a change in pK(app)(b). This shows that the characeristic structural features of nonionic Brij 35 micelles remain essentially unchanged on addition of CTABr under the present experimental conditions. Copyright 1999 Academic Press.

Journal Article↗
PubMed1977

Antibacterial and anthelminthic properties of visnaginone and khellinone derivatives.

The compounds tested, derivatives of visnaginone and khellinone, showed antibacterial activity on gram negative and gram positive micro-organisms. Some of the compounds possess an antibacterial activity on some pathogenic bacteria, i.e. Brucella abortus, for which there is no remedy as yet. All the chalcones tested were inactive except Ib, which showed antiparasitic broad spectrum.

Animals↗
PubMedDate not supplied

MIB-1 index, S-phase fraction, mitotic figure count, and SBR histologic grading in invasive breast carcinoma: a comparative study.

Proliferative activity has been proven to be of prognostic significance in breast carcinoma. This study was performed to compare the different proliferative fractions in the Egyptian population and to define the most suitable one for daily routine use in our surgical pathology laboratories. The proliferative activity of 63 invasive ductal carcinomas was evaluated by immunohistochemical staining of paraffin-embedded tissue sections with MIB-1 rabbit polyclonal antibody and the heat-induced epitope retrieval method, flow cytometric determination of the S-phase fraction (SPF) on frozen tissues, and estimation of the Scarff-Bloom-Richardson (SBR) grading and mitotic figure count (MFC) on hematoxylin and eosin-stained tissue sections. Fifty-two percent of invasive ductal carcinoma were aneuploid. The mean values of MIB-1 index, SPF, and MFC were 17.7 +/- 12.3, 4.9 +/- 3.8, and 5.2 +/- 4.5, respectively, for diploid tumors; while for aneuploid tumors, they were 58.6 +/- 31.9, 19.9 +/- 12.2, and 23.1 +/- 16.9, respectively. These values were significantly higher in aneuploid versus diploid tumors (p < 0.0001). A close correlation was found between MIB-1 index, SPF, MFC, and SBR grading (p < 0.0001). In conclusion, in surgical pathology laboratories that cannot afford the costs of flow cytometry and/or immunostaining, proper SBR grading and MFC can provide an estimation of the proliferation fraction similar to the flow cytometric SPF and MIB-1 immunostaining.

Antigens, Nuclear↗
PubMedDate not supplied

Relation between carotid intima-media thickness, platelet surface activation and endothelial cell markers.

BACKGROUND: The role of platelet activation and endothelial cell damage in the pathogenesis of atherosclerosis was investigated. METHODS: Flow-cytometric detection of platelet activity was accomplished by measuring the surface expression of activated platelet glycoprotein IIb/IIIa (activated CD41) and the lysosomal integral membrane protein (CD63). Levels of thrombomodulin (TM) and von Willebrand factor (vWF) were estimated by the ELISA technique as markers of endothelial cell damage. These procedures were performed in healthy male subjects without obvious signs of atherosclerosis. Also, the intima-media thickness of the carotid artery was measured with high-resolution B- mode ultrasound to quantitate the presence and/or the extent of carotid atherosclerosis. RESULTS: According to ultrasound findings patients were divided into those with apparent evidence of atherosclerosis (AS+) with intima-media thickness >1.1 mm (n = 19) and those without such evidence (AS-) with intima-media thickness <1.1 mm (n = 17). The percentages of activated CD41 and CD63 surface antigen expression were significantly increased in the AS+ compared to AS- subjects. TM levels were elevated in the former group compared to the latter, while vWF levels were not different in the two groups. Multivariate analysis indicated the independent association of carotid atherosclerosis with each of the expression of activated CD41, CD63 as well as TM levels after adjustment of other risk factors. CONCLUSION: This study demonstrates that platelets circulate in an enhanced activation state in asymptomatic atherosclerosis, which is closely related to the degree of endothelial cell damage as expressed by increased plasma levels of TM. The detection of platelet activation can be used as a potential marker for oncoming atherosclerosis.

Adult↗