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  • Author: Mahmoud Amer x
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Treatment of ethyl α-phenylthiocarbamylacetoacetate (1) with aromatic diazonium salts effects acetyl cleavage with the formation of ethyl α-phenylthiocarbamylglyoxalate arylhydrazones derivatives (2 a-e) which afford the anilinopyrazolones (5) and (7) on treatment with hydrazine or phenylhydrazine. The pyrazolones 5 a-e undergo aminoalkylation with formaldehyde and piperidine to give the N-Mannich bases 7 a-e, also obtained by treating the N-hydroxymethyl derivatives (9 a-e) with piperidine.

Bio-guided fractionation of the ethanolic extract of the leaves of Alstonia scholaris (Apocynaceae) growing in Egypt was carried out to evaluate its antihyperglycemic acti vity in alloxan-induced diabetic rats and its hepatoprotective activity against CCl4-induced hepatotoxicity in rats. The ethyl acetate fraction of the ethanolic extract showed the highest antihyperglycemic [(133.6 ± 4.2) mg/mL, relative to metformin with (92.3 ± 2.7) mg/mL] and hepatoprotective [(37.9 ± 1.4) U/L, relative to silymarin with (29.7 ± 0.8) U/L] activities. Four compounds were isolated from this fraction, and identifi ed by spectroscopic techniques and by comparison with reported data: caffeic acid and isoquercitrin for the fi rst time from this plant, in addition to quercetin 3-O-β-D-xylopyranosyl (1''' →2")-β-D-galactopyranoside (major compound) and chlorogenic acid. A validated reversed phase-high-performance liquid chromatography (RP-HPLC) method was developed for the standardization of the bio active ethyl acetate fraction. The calibration curve showed good linearity (r2 > 0.999) within tested ranges. The relative standard deviation of the method was less than 3% for intra- (0.4 - 2.0%) and inter-day (1.9 - 2.8%) assays. Mean recovery of the method was within the range of 98.5 - 102.5%. The minimum detectable concentration of the analyte (LOD) was found to be 0.04 μg/mL. This developed HPLC method was shown to be simple, rapid, precise, reproducible, robust, specifi c, and accurate for quality assessment of the bioactive fraction

Abstract

Garcinia mangostana L. (the queen of fruits, mangosteen, family Guttiferae) is a wealthy source of xanthones. The CHCl3 soluble fraction of the air-dried pericarps of G. mangostana provided a new xanthone: mangostanaxanthone VII (5), along with four known xanthones: mangostanaxanthones I (1) and II (2), gartanin (3) and γ-mangostin (4). The structural verification of these metabolites was achieved by different spectral techniques, including UV, IR, 1D and 2D NMR and HRESIMS. The new metabolite was assessed for cytotoxic potential, using sulforhodamine B (SRB) assay towards the A549 and MCF-7 cancer cell lines. Moreover, its antimicrobial effects were evaluated against various bacterial and fungal strains, using agar disc diffusion assay. Mangostanaxanthone VII showed moderate cytotoxic activity against the A549 and MCF7 cell lines with IC50s 26.1 and 34.8 μM, respectively, compared with doxorubicin (0.74 and 0.41 μM, respectively).

Abstract

An indole alkaloid, 2-(5-hydroxy-1H-indol-3-yl)-2-oxo-acetic acid (1) isolated for the first time from nature, in addition to the nine known compounds 5-hydroxy-1H-indole-3-carboxylic acid methyl ester (2), alocasin B (3), hyrtiosin B (4), α-monopalmitin (5), 1-O-β-D-glucopyranosyl-(2S, 3R, 4E, 8Z)-2-[(2(R)-hydroctadecanoyl) amido]-4,8-octadecadiene-1,3-diol (6), 3-epi-betulinic acid (7), 3-epi-ursolic acid (8), β-sitosterol (9) and β-sitosterol 3-O-β-D-glucoside (10) were isolated from the rhizomes of Alocasia macrorrhiza (Araceae). Their structures were elucidated by 1D and 2D NMR spectroscopic data. Of these compounds, 6 exhibited the strongest cytotoxicity against the four tested human cancer cell lines (IC50 of about 10 µM against Hep-2 larynx cancer cells).

Abstract

Background: The detection and diagnosis of β-thalassaemia for populations with molecular heterogeneity, or diverse ethnic groups, has increased the need for the development of an array high-throughput diagnostic tool that can deliver large scale genetic detection. We report on the update and validation of the ThalassoChip, a β-thalassaemia genetic diagnostic tool which is based on arrayed primer extension (APEX) technology.

Methods: ThalassoChip slides with new and redesigned probes were prepared for testing the microarray. Six hundred and sixty DNA samples collected from eight Mediterranean countries were used for standardisation, optimisation and validation of the ThalassoChip. The β-globin gene region was amplified by PCR, the products were hybridised to the probes after fragmentation and the APEX reaction followed.

Results: The ThalassoChip was updated with new probes and now has the ability to detect 57 β-globin gene mutations and three single nucleotide polymorphisms (SNPs) in a single test. The ThalassoChip as well as the PCR and APEX reactions were standardised and optimised using 500 DNA samples that were previously genotyped using conventional diagnostic techniques. Some probes were redesigned in order to improve the specificity and sensitivity of the test. Validation of the ThalassoChip performed using 160 samples analysed in blinded fashion showed no error.

Conclusions: The updated version of the ThalassoChip is versatile, robust, cost-effective and easily adaptable, but most notably can provide comprehensive genetic diagnosis for β-thalassaemia and other haemoglobinopathies.

Clin Chem Lab Med 2010;48:1713–8.

Abstract

Objectives

Congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency (21-OHD) is a common autosomal recessive disorder caused by defects in the CYP21A2 gene. We aimed to determine the prevalence of the most commonly reported mutations among 21-OHD Egyptian patients and correlate genotype with phenotype.

Methods

Molecular analysis of the CYP21A2 gene was performed for the detection of the six most common point mutations (p.P30L, p.I172N, p.V281L, p.Q318X, the splice site mutation Int2 [IVS2–13A/C>G], and the cluster of three mutations [p.I236N, p.V237E, and p.M239K] designed as CL6). Polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) method was performed on 47 unrelated Egyptian 21α-OH deficiency patients and their available parents to detect the presence of the six most common point mutations.

Results

Screening for the six most common point mutations in CYP21A2 gene, revealed mutations in 87.2% (82/94) of the studied alleles corresponding to 47 Egyptian patients. The most common mutation among the studied cases was IVS2-13C/A>G that was found to be presented in a frequency of 46.8% (44/94). The genotype/phenotype correlations related to null, A, and B groups were with PPV of 100, 55.5, and 83.3%, respectively.

Conclusions

The described method diagnosed CAH in 80.8% of the studied patients. Good correlation between genotype and phenotype in salt wasting and simple virilizing forms is determined, whereas little concordance is seen in nonclassical one. Furthermore, studying the carrier frequency of 21-OHD among the normal population is of great importance.