Tailoring the properties and functions of phosphate/silk/Ag/chitosan scaffolds.

Two novel silk composites of phosphatic phases with nanosilver/chitosan having enhanced biocompatibility were achieved. Hydroxyapatite and octa calcium phosphates were synthesized in situ within silk fibroin/chitosan/nanosilver composites recently studied. Thermo-gravimetric analysis (TGA) and Differential Scanning Calorimetry (DSC) verified their thermal behavior. The structural aspects were characterized applying X-ray diffraction analysis (XRD), transmission electron microscopy (TEM) and field emission scanning electron microscope (FESEM) with EDAX. Additionally X-ray Photoelectron Spectroscopy (XPS) and Fourier Transform Infrared spectroscopy (FTIR) were applied. Mercury porosimeter was used to verify the pore size distribution. The in vitro degradation was followed in D-MEM for 48 h in a cumulative manner for five successive periods. Biochemical analyses of Ca, P and total protein using relevant chemical kits and atomic absorption for silver were performed. ANOVA statistics was carried out. Phosphatic crystalline phases along with the presence of silk, chitosan and nano-silver were developed. The diameters of hydroxyapatite and octa calcium phosphate particles were ~8-17 nm and 15-22 nm respectively. Comparatively higher degradation of Octa composite possessing higher porosity proved in turn more osteoinduction with in situ apatitic development.

Hepatic transcriptomic profiles of European flounder (Platichthys flesus) from field sites and computational approaches to predict site from stress gene responses following exposure to model toxicants.

Genomic technologies offer opportunities to gain a more global assessment of the health status of an organism through an understanding of the functional pathways that are responding to pollutant exposure. We have developed a 13,000 clone cDNA toxicogenomics microarray for Platichthys flesus, the European flounder (EU-GENIPOL Project). We aimed to distinguish the origins of flounder taken from six sampling sites of different pollution status in Northern Europe according to their hepatic gene expression profile using bioinformatic approaches. To determine which gene expression differences may relate to pollutant impact, we have completed complementary laboratory exposures of flounder to selected toxicants and determined the associated gene expression profiles. Using multivariate variable selection coupled with a statistical modelling procedure (GALGO) we can predict geographical site but the accuracy is limited to specific sites. The search space for a combination of genes that effectively predicts class membership is very large, however, by combining the signatures derived from acute laboratory exposure to individual chemicals to limit the search space, a very accurate model for classification of all the different environmental sites was achieved. The final model utilised the expression profiles of 16 clones and validation with a qPCR array comprising these genes correctly assigned the site of origin for fish obtained from three of the sites in an independent sampling. These data would imply that the gene expression fingerprints obtained with these arrays are primarily attributable to variations in chemical pollutant responses at the different sites, indicating their potential utility in environmental impact assessment.

Detection of the bacterium Flavobacterium psychrophilum from a natural infection in rainbow trout, Oncorhynchus mykiss (Walbaum), using formalin-fixed, wax-embedded fish tissues.

The bacterial pathogen Flavobacterium psychrophilum was successfully identified from formalin-fixed, wax-embedded tissue blocks of infected rainbow trout heart and spleen tissues, using a polymerase chain reaction (PCR)-based assay. Filamentous bacteria were observed in haematoxylin and eosin and Giemsa-stained sections but no bacteria were recovered from the diseased fish using standard bacteriology isolation techniques. All infected fish had histopathological evidence of myocarditis or rainbow trout fry syndrome. Immunohistochemistry was attempted using three different anti-F. psychrophilum sera but the results were inconclusive, and an alternative molecular approach was therefore attempted. This paper describes the use of a PCR-based assay to help identify bacteria present in formalin-fixed, wax-embedded tissue samples. This is the first time that this technique has been used for the detection of fish bacteria from diagnostic samples.

Mutations in exons 6 and 7 of TP53 gene correlate positively with serum tumor necrosis factor alpha independent of microsatellite instability in BAT26 gene in Egyptian patients with endometrial carcinoma.

UNLABELLED: Abnormalities in the TP53 gene are the most frequent genetic alterations in human cancers. The role and mechanism of TP53 mutations have been well studied in many types of human cancer. Similarly, the presence of microsatellite instability (MSI) in the DNA mismatch repair system (hMSH2) may provide evidence of faulty DNA mismatch repair. One of the most important locations of MSI is the BAT26 gene. In addition, deranged serum cytokines, especially elevated levels of the tumor necrosis factor (TNF) alpha, have been found in many gynecological conditions. AIMS: The current study aimed at evaluating mutations in exons 6 and 7 of TP53 and the presence of microsatellite instability in BAT26 of the hMSH2 system in Egyptian patients with endometrial carcinoma. The study also evaluated whether there was a correlation between any of these genetic mutations/instability and the tissue expression of estrogen and progesterone receptors and the serum TNF-alpha level. PATIENTS AND METHODS: The current study included 2 groups: a control group comprising 20 healthy women aged 52.21 +/- 5.80 years attending the clinic for routine checkups and 40 patients with endometrial cancer aged 55.30 +/- 6.21 years. Mutations in TP53 and BAT26 were evaluated using polymerase chain reaction-single-strand conformational polymorphism (PCR-SSCP) and automated sequencing while serum TNF-alpha was measured using an ELISA technique. Estrogen and progesterone receptor expression in biopsy tissue was evaluated using immunohistochemical staining. RESULTS: Seven of the 40 patients (17.5%) were positive for TP53 gene alterations in exon 6, while 9 patients (22.5%) were positive for TP53 alterations in exon 7. Cases positive for TP53 mutations had higher tumor stages. Ten patients (25%) showed MSI in BAT26. Nearly all patients with mutations in BAT26 had a strong family history for endometrial cancer (chi2=13.33, p<0.05). There was no positive correlation between the presence of MSI in the BAT26 gene and mutations in the TP53 gene or high serum TNF-alpha levels. Cases positive for TP53 mutations had a significantly higher level of TNF-alpha than cases negative for TP53 mutations (p<0.05). Cases showing mutations in exon 6 or 7 of TP53 showed a significantly higher intensity of immunohistochemical staining for estrogen and progesterone receptor expression in biopsy tissue than cases negative for mutations. (chi2=8.11, p<0.05). CONCLUSION: Our results suggest that the development of endometrial carcinoma is probably mediated through a multi-step carcinogenesis pathway and mutation of TP53 does not necessarily result from the presence of microsatellite instability in BAT26. The high serum TNF-alpha levels detected in our patients may represent an immunological antitumor response that was particularly evident in cases positive for TP53 mutations.

Sugarhydrazones of 2-hydrazinoquinolines and their antimicrobial activity.

Sugar hydrazones from 2-hydrazinoquinoline, 2-hydrazino-6-methyllepidine, 6-chloro-2-hydrazino lepidine, 7-chloro-2-hydrazinolepidine, and 7-chloro-2-hydrazino-3-nitroquinoline were prepared. Their acetylation, benzoylation, periodate oxidation, oxidation with lead tetraacetate and bromination have been investigated. The antimicrobial activities of the hydrazones were evaluated. Some compounds showed moderate activity.

Bacterial contamination of water wells in Wadi el-Sheikh area, in southern Sinai.

A bacterial assessment of water supplies must be done in Egypt as in order to improve the quality of useable water. Saint Katherine, Southern Sinai, was selected as being a populated area where wells are the only source of water for the local population. During one year, water of seven wells in Wadi El-Shiekh were bactiologically studied (El-Arbaien, Haron, Eid, Zitona, Farhan, Sahab and Gofa). The pouring plate technique was used to estimate the total viable bacterial count (TVB). The most probable number (MPN) technique was used to estimate total coliform (TC) and fecal coliform (FC) bacterial count. A result indicates that Al-Arabaien well has the least count of TVB throughout the year of study, possibly because of to geologic nature, low content of salts, low pH value of the water of this well. Zitona and Eid gave relatively the highest counts of TVB. This might had been due to the way in which these well were used. Intermediate counts were recorded in other wells. TC counts reached their maximum in Gofa and Farhan in Autumn. Percentages of FC among the TC counts were higher also in Autum in five wells (Al-Arbaien, Haron, Zitona, Eid and Sahab). This might had had been due to the increased agricultural activities around these wells. TC counts reached their minimum in Zitona during Winter, Spring and Summer. Five families of bacteria were identified form water samples, namely: Bacillaceae, Streptococcaceae Micrococcaceae, Neisseriaceae and Enterobacteriaceae. The geological condition of each well, some meteorological factors, and inhabitants activities around the well were found to play an important role in variability of TVB, TC, and FC counts. It is suggested that the inhabitants be educated of the best and healthy ways of using water and the good healthy habits.

Colorimetric assay of quinine and quinidine in raw materials, formulations, and biological fluids.

The two characteristic erythroquinine and thalleioquin tests for quinine and quinidine were studied to optimize the experimental conditions for quantitative analysis. Both methods were quantitatively sensitive for either quinine or quinidine in a concentration range of 0.1--10 microgram/ml with the erythroquinine method and of 3--50 microgram/ml with the thalleioquin method. A TLC--colorimetric method also is described for the assay of quinine and quinidine in the presence of cinchonine, cinchonidine, and other cinchona alkaloids. The results were compared with those obtained with a spectrophotometric method.

Selective estimation of aconitine in presence of aconine and benzoylaconine.

A selective and simple colorimetric method is presented for the estimation of aconitine in drugs in the presence of aconine and benzoylaconine. The method is based on the formation of an iron hydroxamate complex through the acetate ester group to which the biological activity is due. The color is measured at 530 nm (5--250 microgram/ml). Under the experimental conditions, neither the benzoyl group of benzoylaconine nor aconine is involved in the process of hydroxylaminolysis.

Spectrophotometric assay of nicotinic acid in blood. Assessment of its daily profile in humans.

A sensitive, simple, and specific spectrophotometric method is developed for estimating nicotinic acid in blood. The method depends upon reducing nicotinic acid by Zn/HCl to piperidine-3-carboxylic acid. The latter is complexed with CS2 and ammoniacal CuSO4 to form the yellow Cu-dithiocarbamate complex. The color is measured at 445 nm, obeys Beer's law (20--900 microgram/ml), and remains stable for more than 4 h. Efficiency of recoveries from standards and blood samples was tested and proved satisfactory at different levels of concentrations. The method shows good recovery (99.66%) and reasonable standard deviation (+/- 0.29%) in comparison with the cyanogen bromide method (98.3% and +/- 0.73%, respectively). The results obtained show a natural gradual decline in blood nicotinic acid level during the course of the day.

Colorimetric assay of reserpine in formulations and biological fluids.

Two colorimetric methods are presented for determining reserpine. In the first method, an iron hydroxamate complex is formed through the ester group in position 16 in the reserpine molecule. The color is measured at 535 nm (0.5-6 mg/25 ml). This method is useful for routine and control analyses of reserpine formulations. In the second method the tertiary amino group of reserpine reacts with 2% citric acid in acetic anhydride to form a red-violet complex which is measured at 505 nm (5-400 mug/10 ml). This method could be useful in measuring trace amounts of reserpine present in biological fluids.

Colorimetric determination of aconitine in galenicals and in biological samples.

A sensitive method is presented for determining aconitine. Aconitine is complexed with Co2+, the aconitine-cobalt complex is extracted with chloroform, and the absorbance is measured at 320 nm. The sensitivity of the method ranged between 0.06 and 3 mg/25 ml, and the color was stable for 6 hr. The method was successfully applied for the quantitative determination of aconitine in animal tissues.

Spectrophotometric assay of salsolidine hydrochloride.

The proposed method is based on the reaction of salsolidine HCl with carbon disulfide and ammoniacal copper sulfate. The resulting salsolidine-copper-dithiocarbamate complex is extracted with benzene and measured spectrophotometrically at 448 nm. The method is applicable for the detection of 40-500 mug salsolidine/5 ml.

Colorimetric and volumetric assays of colchicine in galenicals and in pharmaceutical preparations.

In the method described the amide group in the colchicine molecule is reduced with lithium aluminum hydride to the corresponding secondary amine. The latter is extracted with chloroform and then determined either colorimetrically by the copper dithiocarbamate reaction or volumetrically by dissolving in acid and titrating with sodium hydroxide or perchloric acid. The results were comparable with those obtained by the Egyptian Pharmacopoeia spectrophotometric method.