Comparison of vegetative anatomy of piperales. I. Juvenile xylem of twigs

Medullary bundles of Piperaceae resemble those of Ranunculaceae. The nature of tracheary elements of primary xylem suggests that Houttuynia cordata (Saururaceae), Piper cubeba (Piperaceae) and Chloranthus officinalis (Chloranthaceae) are of lower evolutionary status than others. Among these three, P. cubeba shows stratification of secondary xylem, a specialized character. Lateral wall of metaxylem tracheary elements and distribution of bundles of Peperomia, suggest their primitive status and distinctness, supporting separation of "Peperomiacea:" (of NOVAK). Piper cubeba, Houttuynia and Chloranthus bear one important Ranunculaceous character: scalariform perforation in primary vessels. Primitive species of Peperomia carry probably another Ranunculaceous character, i.e., many circles of medullary bundles. Shape and pattern of vascular bundles of Piper cubeba, Houttuynia and Chloranthus are similar. Other species of Piper show modifications. Peperomia represents another distinct pattern.     

Mitochondrial DNA mutations in respiratory complex-I in never-smoker lung cancer patients contribute to lung cancer progression and associated with EGFR gene mutation

Mitochondrial DNA (mtDNA) mutations were reported in different cancers. However, the nature and role of mtDNA mutation in never‐smoker lung cancer patients including patients with epidermal growth factor receptor (EGFR) and KRAS gene mutation are unknown. In the present study, we sequenced entire mitochondrial genome (16.5 kb) in matched normal and tumors obtained from 30 never‐smoker and 30 current‐smoker lung cancer patients, and determined the mtDNA content. All the patients' samples were sequenced for KRAS (exon 2) and EGFR (exon 19 and 21) gene mutation. The impact of forced overexpression of a respiratory complex‐I gene mutation was evaluated in a lung cancer cell line. We observed significantly higher (P = 0.006) mtDNA mutation in the never‐smokers compared to the current‐smoker lung cancer patients. MtDNA mutation was significantly higher (P = 0.026) in the never‐smoker Asian compared to the current‐smoker Caucasian patients' population. MtDNA mutation was significantly (P = 0.007) associated with EGFR gene mutation in the never‐smoker patients. We also observed a significant increase (P = 0.037) in mtDNA content among the never‐smoker lung cancer patients. The majority of the coding mtDNA mutations targeted respiratory complex‐I and forced overexpression of one of these mutations resulted in increased in vitro proliferation, invasion, and superoxide production in lung cancer cells. We observed a higher prevalence and new relationship between mtDNA alterations among never‐smoker lung cancer patients and EGFR gene mutation. Moreover, a representative mutation produced strong growth effects after forced overexpression in lung cancer cells. Signature mtDNA mutations provide a basis to develop novel biomarkers and therapeutic strategies for never‐smoker lung cancer patients. J. Cell. Physiol. 227: 2451–2460, 2012. © 2011 Wiley Periodicals, Inc.     

Genome-wide analysis of genetic alterations in testicular primary seminoma using high resolution single nucleotide polymorphism arrays

Testicular germ cell tumors (TGCT) represent the most common malignancy among young males. To our knowledge no comprehensive Copy Number Variation (CNVs) studies of TGCT using high-resolution Single Nucleotide Polymorphism (SNP) array have been performed. By a genome-wide analysis of CNV and loss of heterozygosity (LOH) in 25 primary seminomas, we confirmed several previously reported genomic alterations and discovered eight novel genomic alterations including amplifications and homozygous deletions. Moreover, a comparison of genomic alterations of early and late stage seminoma identified CNVs that correlate with progression, which included deletions in chromosomes 4q, 5p, 9q, 13q and 20p and amplifications in chromosomes 9q and 13q. We compared previously perform Affymetrix expression analysis in a subset of samples and found robust correlation between expression and genomic alterations. Furthermore, high correlations (40-75%) were observed between CNV by SNP analysis and quantitative PCR. Our findings may lead to better understanding of TGTC's pathogenesis.     

Effect of green tea polyphenols on angiogenesis induced by an angiogenin-like protein

Angiogenesis is a fundamental process by which new blood vessels are formed. The angiogenesis process is induced by several growth factors. Among them angiogenin is the most potent blood vessel inducer known. In this paper, we have investigated the effect of green tea polyphenols, mainly the catechins, on an angiogenin-like protein induced angiogenesis process. The angiogenin-like protein was isolated from goat serum and the effect of green tea components was tested by the chicken chorioallantoic membrane (CAM) assay. The results show that green tea components are capable of reducing the vascularization on CAM that is induced by the angiogenin-like protein.     

Gametic embryogenesis and callogenesis in Isolated microspore culture of Jatropha curcas L. a recalcitrant bioenergy crop

Plant Cell, Tissue and Organ Culture (PCTOC) - Jatropha curcas is an undomesticated crop and its plantations did not meet commercial expectation due to absence of high yielding commercial line with...     

Intergenerational paternal effect of adult density in Drosophila melanogaster

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