Oxidants and antioxidants in atherogenesis. An appraisal

Oxidized low density lipoprotein (Ox-LDL) has a plethora of components that are not present in native LDL. Their presence and quantity depends on the nature, type, and extent of oxidation. Lipids esterified to oxidized fatty acids are the major components formed during the early phase of oxidation and these show a number of proatherogenic properties in in vitro cell culture systems. Recently, evidence has been forthcoming to suggest that some of these oxidized lipids also could elicit "antioxidant;-antiatherogenic" responses from cells. Moreover, some of the cellular effects of Ox-LDL that were previously interpreted as atherogenic could also be reinterpreted to suggest an antiatherogenic cellular response. In addition to the above, the antioxidants that are carried in lipoproteins could have anomalous behavior attributable to their metabolism, ability to be internalized by arterial cells, and the presence of oxidative systems that could render them prooxidants. In conclusion, there are numerous contributing factors that need to be studied and understood before antioxidant therapy becomes an option for the treatment for cardiovascular diseases.     

ARC: automated resource classifier for agglomerative functional classification of prokaryotic proteins using annotation texts

Functional classification of proteins is central to comparative genomics. The need for algorithms tuned to enable integrative interpretation of analytical data is felt globally. The availability of a general,automated software with built-in flexibility will significantly aid this activity. We have prepared ARC (Automated Resource Classifier), which is an open source software meeting the user requirements of flexibility. The default classification scheme based on keyword match is agglomerative and directs entries into any of the 7 basic non-overlapping functional classes: Cell wall, Cell membrane and Transporters (C), Cell division (D), Information (I), Translocation (L), Metabolism (M), Stress(R), Signal and communication (S) and 2 ancillary classes: Others (O) and Hypothetical (H).The keyword library of ARC was built serially by first drawing keywords from Bacillus subtilis and Escherichia coli K12. In subsequent steps,this library was further enriched by collecting terms from archaeal representative Archaeoglobus fulgidus, Gene Ontology, and Gene Symbols. ARC is 94.04% successful on 6,75,663 annotated proteins from 348 prokaryotes. Three examples are provided to illuminate the current perspectives on mycobacterial physiology and costs of proteins in 333 prokaryotes. ARC is available at http://arc.igib.res.in.     

ARC: Automated Resource Classifier for agglomerative functional classification of prokaryotic proteins using annotation texts

Functional classification of proteins is central to comparative genomics. The need for algorithms tuned to enable integrative interpretation of analytical data is felt globally. The availability of a general, automated software with built-in flexibility will significantly aid this activity. We have prepared ARC (Automated Resource Classifier), which is an open source software meeting the user requirements of flexibility. The default classification scheme based on keyword match is agglomerative and directs entries into any of the 7 basic non-overlapping functional classes: Cell wall, Cell membrane and Transporters (C), Cell division (

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), Information (I), Translocation (\(\mathcal{L}\)), Metabolism (

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), Stress (

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), Signal and communication(S) and 2 ancillary classes: Others (O) and Hypothetical (

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). The keyword library of ARC was built serially by first drawing keywords from Bacillus subtilis and Escherichia coli K12. In subsequent steps, this library was further enriched by collecting terms from archaeal representative Archaeoglobus fulgidus, Gene Ontology, and Gene Symbols. ARC is 94.04% successful on 6,75,663 annotated proteins from 348 prokaryotes. Three examples are provided to illuminate the current perspectives on mycobacterial physiology and costs of proteins in 333 prokaryotes. ARC is available at http://arc.igib.res.in .

     

Evidence in favor of linkage to human chromosomal regions 18q, 5q and 13q for bicuspid aortic valve and associated cardiovascular malformations

The aim of this study was to identify regions of the genome that harbor genes influencing inheritance of bicuspid aortic valve (BAV) and/or associated cardiovascular malformation (CVM). Aortic valve disease is an important clinical problem, which often results in valve replacement, the second most common cardiac surgery in the United States. In every age group, a majority of cases of valve disease involves a BAV. BAV is the most common CVM with a reported prevalence of 1–2%. Heritability studies indicate that BAV determination is almost entirely genetic. We used a family-based genome-wide linkage analysis with microsatellite markers. Parametric and nonparametric analyses were performed with the software GENEHUNTER and SOLAR (Sequential Oligogenic Linkage Analysis Routines). Thirty-eight families (353 subjects) with BAV and/or associated CVM were assessed. Each participant underwent a standardized echocardiographic examination. The highest LOD score, 3.8, occurred on chromosome 18q between markers D18S68 and D18S1161. Two other chromosomal regions, 5q15–21 (between D5S644 and D5S2027) and 13q33-qter (between D13S1265 and 13qter), exhibited suggestive evidence of linkage (LOD > 2.0). Further, two previously reported linkage peaks on 9q34 and 17q24 were replicated in family specific analyses. No significant X chromosome linkage peaks were identified. In this genome-wide scan we demonstrate for the first time, that BAV and/or associated CVM exhibit linkage to chromosomes 18q, 5q and 13q. These regions likely contain genes whose mutation results in BAV and/or associated CVM indicating their important role in valvulogenesis and cardiac development. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. Lisa J. Martin and Vijaya Ramachandran have contributed equally to this work.     

Proteinase-activated receptor-2 activating peptides: distinct canine coronary artery receptor systems

In canine coronary artery preparations, the proteinase-activated receptor-2 (PAR(2)) activating peptides (PAR(2)-APs) SLIGRL-NH(2) and 2-furoyl-LIGRLO-NH(2) caused both an endothelium-dependent relaxation and an endothelium-independent contraction. Relaxation was caused at peptide concentrations 10-fold lower than those causing a contractile response. Although trans-cinnamoyl-LIGRLO-NH(2), like other PAR(2)-APs, caused relaxation, it was inactive as a contractile agonist and instead antagonized the contractile response to SLIGRL-NH(2). RT-PCR-based sequencing of canine PAR(2) revealed a cleavage/activation (indicated by underlines) sequence (SKGR/SLIGKTDSSLQITGKG) that is very similar to the human PAR(2) sequence (R/SLIGKV). As a synthetic peptide, the canine PAR-AP (SLIGKT-NH(2)) was a much less potent agonist than either SLIGRL-NH(2) or 2-furoyl-LIGRLO-NH(2), either in the coronary contractile assay or in a Madin-Darby canine kidney (MDCK) cell PAR(2) calcium signaling assay. In the MDCK signaling assay, the order of potencies was as follows: 2-furoyl-LIGRLO-NH(2) > SLIGRL-NH(2) = trans-cinnamoyl-LIGRLO-NH(2) > SLIGKT-NH(2), as expected for PAR(2) responses. In the coronary contractile assay, however, the order of potencies was very different: SLIGRL-NH(2) > 2-furoyl-LIGRLO-NH(2) > SLIGKT-NH(2), trans-cinnamoyl-LIGRLO-NH(2) = antagonist. Because of 1) the distinct agonist (relaxant) and antagonist (contractile) activity of trans-cinnamoyl-LIGRLO-NH(2) in the canine coronary contractile assays, 2) the different concentration ranges over which the peptides caused either relaxation or contraction in the same coronary preparation, and 3) the markedly distinct structure-activity profiles for the PAR-APs in the coronary contractile assay, compared with those for PAR(2)-mediated MDCK cell calcium signaling, we suggest that the canine coronary tissue possesses a receptor system for the PAR-APs that is distinct from PAR(2) itself.     

Identification of calcitonin expression in the chicken ovary: influence of follicular maturation and ovarian steroids

Calcitonin (CALCA), a hormone primarily known for its role in calcium homeostasis, has recently been linked to reproduction, specifically as a marker for embryo implantation in the uterus. Although CALCA expression has been documented in several tissues, there has been no report of production of CALCA in the ovary of any vertebrate species. We hypothesized that the Calca gene is expressed in the chicken ovary, and its expression will be altered by follicular maturation or gonadal steroid administration. Using RT-PCR, we detected Calca mRNA and the calcitonin receptor (Calcr) mRNA in the granulosa and theca layers of preovulatory and prehierarchial follicles. Both CALCA and Calca mRNA were localized in granulosa and thecal cells by confocal microscopy. Using quantitative PCR analysis, F1 follicle granulosa layer was found to contain significantly greater Calca mRNA and Calcr mRNA levels compared with those of any other preovulatory or prehierarchial follicle. The granulosa layer contained relatively greater Calca and Calcr mRNA levels compared with the thecal layer in both prehierarchial and preovulatory follicles. Progesterone (P(4)) treatment of sexually immature chickens resulted in a significantly greater abundance of ovarian Calca mRNA, whereas estradiol (E(2)) or P(4) + E(2) treatment significantly reduced ovarian Calca mRNA quantity. Treatment of prehierarchial follicular granulosa cells in vitro with CALCA significantly decreased FSH-stimulated cellular viability. Collectively, our results indicate that follicular maturation and gonadal steroids influence Calca and Calcr gene expression in the chicken ovary. We conclude that ovarian CALCA is possibly involved in regulating follicular maturation in the chicken ovary.     

Cytologic diagnosis of metastatic hepatocellular carcinoma presenting as an orbital mass. A case report

BACKGROUND: Hepatocellular carcinoma (HCC) metastasizing to the orbit is extremely rare. In the 13 cases reported in the English-langnage literature, the diagnosis was confirmed by fine needle aspiration (FNA) cytology only once. This is the second such case to be diagnosed by FNA cytology and the first to be reported from the Indian subcontinent. CASE: A 76-year-old woman presented with progressive proptosis, bulging of the globe and loss of vision in the right eye. Clinical and radiologic evidence favored a primary orbital tumor with liver metastasis. Cytologic examination of aspirated material from the orbital and liver masses showed features similar to those of HCC. CONCLUSION: Recognition of the cytologic features of HCC permits its diagnosis in metastatic sites. FNA can be employed as an effective tool for diagnosing HCC at metastatic sites, especially when biopsy is technically difficult.     

Antitumor and cytotoxic effects of Phyllanthus polyphyllus on Ehrlich ascites carcinoma and human cancer cell lines

To evaluate the antitumor and cytotoxic activity of methanol extract of Phyllanthus polyphyllus (MPP) in mice and human cancer cell lines, the antitumor activity of MPP was evaluated against an Ehrlich ascites carcinoma (EAC) tumor model. The activity was assessed using survival time, hematological studies, lipid peroxidation (LPO), antioxidant enzymes such as superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx), glutathione S-transferase (GST), solid tumor mass, and short-term in vitro cytotoxicity. The cytotoxic activity of MPP was evaluated using human breast cancer (MCF7), colon cancer (HT29), and liver cancer (HepG2) cell lines Oral administration of MPP (200 and 300 mg/kg) increased the survival time and significantly reduced the solid tumor volume in a dose-dependent manner. Hematological parameters, protein, and packed cellular volume (PCV), which were altered by tumor inoculation, were restored. MPP significantly decreased the levels of LPO, GPx, GST, and significantly increased the levels of SOD and CAT. In a cytotoxicity study against human cancer cell lines, MPP was found to have IC50 values of 27, 42 and 38 microg/ml on MCF-7, HT-29, and HepG2 cells respectively. MPP possessed significant antitumor and cytotoxic activity on EAC and human cancer cell lines.