Distinct cagA EPIYA Motifs are Associated with Ethnic Diversity in Malaysia and Singapore

Background:  In vitro studies have shown that the biologic activity of CagA is influenced by the number and class of EPIYA motifs present in its variable region as these motifs correspond to the CagA phosphorylation sites. It has been hypothesized that strains possessing specific combinations of these motifs may be responsible for gastric cancer development. This study investigated the prevalence of cagA and the EPIYA motifs with regard to number, class, and patterns in strains from the three major ethnic groups within the Malaysian and Singaporean populations in relation to disease development.
Materials and methods:  Helicobacter pylori isolates from 49 Chinese, 43 Indian, and 14 Malay patients with functional dyspepsia (FD) and 21 gastric cancer (GC) cases were analyzed using polymerase chain reaction for the presence of cagA and the number, type, and pattern of EPIYA motifs. Additionally, the EPIYA motifs of 47 isolates were sequenced.
Results:  All 126 isolates possessed cagA , with the majority encoding EPIYA-A (97.6%) and all encoding EPIYA-B. However, while the cagA of 93.0% of Indian FD isolates encoded EPIYA-C as the third motif, 91.8% of Chinese FD isolates and 81.7% of Chinese GC isolates encoded EPIYA-D ( p  < .001). Of Malay FD isolates, 61.5% and 38.5% possessed EPIYA-C and EPIYA-D, respectively. The majority of isolates possessed three EPIYA motifs; however, Indian isolates were significantly more likely to have four or more ( p  < .05).
Conclusion:  Although, H. pylori strains with distinct cagA -types are circulating within the primary ethnic groups resident in Malaysia and Singapore, these genotypes appear unassociated with the development of GC in the ethnic Chinese population. The phenomenon of distinct strains circulating within different ethnic groups, in combination with host and certain environmental factors, may help to explain the rates of GC development in Malaysia.     

Regioselective facile one-pot Friedländer synthesis of sugar-based heterocyclic biomolecules

Regioselective facile one-pot synthesis of 16 different sugar-based quinoline, naphthyridine, and xanthone derivatives is reported. The compounds are characterized by NMR spectroscopy and elemental analysis. The β-Anomeric form of the sugar moiety was identified from ¹H NMR studies. Antimicrobial studies of these sugar-heterocyclic derivatives, 3a, 3b, 3f, 5c, 7a, 7b, and 7c show excellent activity against different microbes.     

New bacterial culture medium for production of mosquito pathogenic bacilli using agro-poultry industrial wastes

A cost-effective technology has been developed to utilise bioorganic wastes as culture media, to produce mosquitocidal biopesticides, Bacillus sphaericus and B. thuringiensis serovar israelensis. The mosquitocidal spore/crystal toxins produced from the experimental medium (chicken feather waste, CFW+paddy husk waste, PHW) was higher than that of the conventional medium (Nutrient Yeast Extract Salt Medium, NYSM). The bacterial toxins produced from different media (NYSM, CFW, PHW, CFW+PHW) were bioassayed against mosquito vectors and the toxic effect was found to be significant. The use of chicken feathers and paddy husk wastes as bacterial culture media is cost-effective and economical for the production of these mosquito pathogenic bacilli.     

Myocardial ischemia and reperfusion injury in rats: lysosomal hydrolases and matrix metalloproteinases mediated cellular damage

The aim of this study was to evaluate the time course events of cellular damage during myocardial ischemia and reperfusion injury in rats and to find out a correlation between the structural alterations with respect to the biochemical changes. Cardiac biomarkers and lysosomal enzymes viz. cathepsin D, acid phosphatase and β-glucuronidase and matrix metalloproteinases (MMPs) were evaluated at different time points, in response to ischemia-reperfusion induced oxidative stress in an isolated rat heart model perfused in Langendorff mode. Microscopically, changes in myocardial architecture, myofibrillar degradation, and collagen (COL) integrity were studied using hematoxylin-eosin, Masson’s trichrome and toluidine blue staining techniques. A three-fold increase in the level of myoglobin was observed after 30 min of ischemia followed by 120 min of reperfusion as compared to 15 min ischemia, 120 min reperfusion. Similarly, a significant increase (P < 0.05) in the levels of lipid peroxides and superoxide anion coupled with a decrease in enzymatic and nonenzymatic antioxidant levels were observed. A concomitant increase in the activity of cathepsin D (24.07 ± 0.95) and a higher expression of MMPs after 120 min of reperfusion following 30 min ischemia were shown to correlate with the myocardial damage as shown by histopathology, suggesting that free radical induced activation of cathepsin D and MMPs could mediate early damage during myocardial ischemia and reperfusion.     

Down-regulation of WW domain-containing oxidoreductase induces Tau phosphorylation in vitro. A potential role in Alzheimer's disease

Numerous enzymes hyperphosphorylate Tau in vivo, leading to the formation of neurofibrillary tangles (NFTs) in the neurons of Alzheimer's disease (AD). Compared with age-matched normal controls, we demonstrated here that the protein levels of WW domain-containing oxidoreductase WOX1 (also known as WWOX or FOR), its Tyr33-phosphorylated form, and WOX2 were significantly down-regulated in the neurons of AD hippocampi. Remarkably knock-down of WOX1 expression by small interfering RNA in neuroblastoma SK-N-SH cells spontaneously induced Tau phosphorylation at Thr212/Thr231 and Ser515/Ser516, enhanced phosphorylation of glycogen synthase kinase 3beta (GSK-3beta) and ERK, and enhanced NFT formation. Also an increased binding of phospho-GSK-3beta with phospho-Tau was observed in these WOX1 knock-down cells. In comparison, increased phosphorylation of Tau, GSK-3beta, and ERK, as well as NFT formation, was observed in the AD hippocampi. Activation of JNK1 by anisomycin further increased Tau phosphorylation, and SP600125 (a JNK inhibitor) and PD-98059 (an MEK1/2 inhibitor) blocked Tau phosphorylation and NFT formation in these WOX1 knock-down cells. Ectopic or endogenous WOX1 colocalized with Tau, JNK1, and GSK-3beta in neurons and cultured cells. 17Beta-estradiol, a neuronal protective hormone, increased the binding of WOX1 and GSK-3beta with Tau. Mapping analysis showed that WOX1 bound Tau via its COOH-terminal short-chain alcohol dehydrogenase/reductase domain. Together WOX1 binds Tau via its short-chain alcohol dehydrogenase/reductase domain and is likely to play a critical role in regulating Tau hyperphosphorylation and NFT formation in vivo.     

Novel fermentation media for production of Bacillus thuringiensis subsp. israelensis

The production of Bacillus thuringiensis subsp. israelensis (deBarjac) (Bti) as a biopesticide is not cost-effective using existing fermentation technology. In this study, we explored the use of several less expensive alternative culture media (potato, common sugar, and Bengal gram) for the growth and production of Bti. Growth was obtained in all tested media and was comparable to that obtained in conventional medium (Luria-Bertani). Toxicity assays showed that the toxin produced from the novel growth media were effective in killing larvae of Culex quinquefasciatus, Anopheles stephensi, and Aedes aegypti and toxicity was comparable to that produced from Luria-Bertani medium. These observations suggest that potato can be used as a cheap source of culture medium for the production of Bti toxin in mosquito control programs.     

Genetics of drought tolerance during seed germination in tomato: inheritance and QTL mapping.

A BC1 population (N = 1000) of an F1 hybrid between a stress-sensitive Lycopersicon esculentum breeding line (NC84173; maternal and recurrent parent) and a germination stress-tolerant Lycopersicon pimpinellifolium accession (LA722) was evaluated for seed germination rate under drought stress (DS) (14% w/v polyethyleneglycol-8000, water potential approximately -680 kPa), and the most rapidly germinating seeds (first 3% to germinate) were selected. The 30 selected BC1 seedlings were grown to maturity and self pollinated to produce BC1S1 progeny seeds. Twenty of the 30 selected BC1S1 progeny families were evaluated for germination rate under DS and their average performance was compared with that of a "nonselected" BC1S1 population of the same cross. Results indicated that selection for rapid germination under DS significantly improved progeny germination rate under DS (selection gain = 19.6%), suggesting a realized heritability of 0.47 for rate of germination under DS in this population. The 30 selected BC1 plants were subjected to restriction fragment length polymorphism (RFLP) analysis, and marker allele frequencies for 119 RFLP markers which spanned 1153 cM of the 12 tomato chromosomes were determined. A distributional extreme marker analysis, which measures statistical differences in marker allele frequencies between a selected and a nonselected population, detected four quantitative trait loci (QTLs) for rate of germination under DS in this population. Of these, two QTLs, located on chromosomes 1 and 9, were contributed by the L. pimpinellifolium donor parent and had larger effects than the other two QTLs, located on chromosomes 8 and 12, which were contributed by the L. esculentum recurrent parent. A few BC1S1 families were identified with all or most of the identified QTLs and with germination rates comparable with that of LA722. These families should be useful for the development of germination drought-tolerant tomato lines using marker-assisted selection (MAS). The overall results indicate that drought tolerance during seed germination in tomato is genetically controlled and potentially could be improved by directional phenotypic selection or MAS.     

The dyad gene is required for progression through female meiosis in Arabidopsis

In higher plants the gametophyte consists of a gamete in association with a small number of haploid cells, specialized for sexual reproduction. The female gametophyte or embryo sac, is contained within the ovule and develops from a single cell, the megaspore which is formed by meiosis of the megaspore mother cell. The dyad mutant of Arabidopsis, described herein, represents a novel class among female sterile mutants in plants. dyad ovules contain two large cells in place of an embryo sac. The two cells represent the products of a single division of the megaspore mother cell followed by an arrest in further development of the megaspore. We addressed the question of whether the division of the megaspore mother cell in the mutant was meiotic or mitotic by examining the expression of two markers that are normally expressed in the megaspore mother cell during meiosis. Our observations indicate that in dyad, the megaspore mother cell enters but fails to complete meiosis, arresting at the end of meiosis 1 in the majority of ovules. This was corroborated by a direct observation of chromosome segregation during division of the megaspore mother cell, showing that the division is a reductional and not an equational one. In a minority of dyad ovules, the megaspore mother cell does not divide. Pollen development and male fertility in the mutant is normal, as is the rest of the ovule that surrounds the female gametophyte. The embryo sac is also shown to have an influence on the nucellus in wild type. The dyad mutation therefore specifically affects a function that is required in the female germ cell precursor for meiosis. The identification and analysis of mutants specifically affecting female meiosis is an initial step in understanding the molecular mechanisms underlying early events in the pathway of female reproductive development.     

Investigation on<Emphasis Type="Italic"> Semecarpus Lehyam</Emphasis>—a<Emphasis Type="Italic"> Siddha</Emphasis> medicine for breast cancer

The use of complementary and alternative medicines for breast cancer patients has been increasing every year. Traditional Indian systems of medicine, such as Siddha, have been reported to benefit patients in India through herbal interventions for cancer. One such herbal medicine is Semecarpus Lehyam (SL), and this study aims at providing a scientific basis for the anti-tumor property of SL with respect to breast cancer. SL was subjected to serial extraction with four organic solvents of increasing polarity (n-hexane, chloroform, ethyl acetate, n-butanol and water). The solvents from all fractions were removed, dried and dissolved in dimethyl sulfoxide for testing their anti-tumor activity against two breast cancer cell lines, MCF-7 [estrogen receptor (ER)-positive] and MDA 231 (ER-negative) using cell viability and apoptosis assays. The most potent SL fractions were also combined with radiation and doxorubicin to determine the radio- and chemo-sensitizing effects of SL on these breast cancer cell lines. In terms of cytotoxicity as well as induction of apoptosis, the n-hexane and chloroform fractions of SL were more significantly active against MDA 231 cells than MCF-7 cells. The n-butanol fraction of SL showed some activity against MCF-7 cells. When combined with radiation or doxorubicin, the n-hexane and chloroform fractions enhanced the radio-sensitivity (11.8-fold) and chemo-sensitivity (6.5-fold) of MDA 231 cells. This study demonstrated SL to be a potent anti-tumor agent against the ER-negative breast cancer cell line. The study is also the first step in the scientific validation of SL for use against breast cancer, particularly the ER-negative type.