STUDIES ON FACTORS INFLUENCING HIGH-DENSITY LIPOPROTEIN FUNCTIONALITY AND REVERSE CHOLESTEROL TRANSPORT

Coronary artery disease (CAD) in dyslipidemic and diabetic subjects remains the leading cause of death in the Western society. Current therapeutic strategies to prevent cardiovascular diseases are primarily based on the use of statins, which inhibit key enzyme in the cholesterol synthesis, HMG-CoA reductase. Another prominent risk factor for developing premature atherosclerosis is the low levels of high-density lipoprotein cholesterol (HDL-C). Despite documented benefits of statins a good proportion of individuals still remain at a higher risk of developing CAD. Therefore, focus has shifted on HDL-raising therapeutics to further improve the CV outcome. While Niacin and fenofibrate have not shown clinical benefits in two separate trials, results from CETP inhibitors, Torcetrapib and Dalcetrapib, in phase 3 clinical studies have been disappointing despite substantial increase in HDL-C. One of the challenges encountered with measuring plasma HDL as a biomarker for cardiovascular risk is the fact that the antiinflammatory HDL becomes pro-inflammatory after it undergoes oxidative modification in diabetics. Pro-inflammatory states have also been shown to reduce HDL functionality. Thus, the lack of translatability of animal results to humans has further added challenges in the HDL therapeutics area. These findings necessitated rethinking about HDL therapeutics leading to transition in HDL therapy concept that seems to focus more around HDL functionality rather than HDL level. This PhD dissertation focuses on factors that influence HDL functionality and analyzes a correlation between HDL functionality and aortic lipid deposition. Several agents that raise HDL levels have been utilized to dissect HDL functionality. In addition, animal model of diabetes and atherosclerosis was employed to establish a correlation between HDL functionality, hyperglycemia and inflammation. Through a series of studies, it is shown that HDL function correlates with beneficial effects, and diabetes and inflammation dampens HDL functionality leading to increased accumulation of aortic lesion formation. Agents that attenuate hyperlipidemia, glycemic index and proinflammatory state improved HDL functionality leading to reductions in atherosclerotic burden

Sequencing of 28SrRNA Gene for Identification of Trichoderma longibrachiatum 28CP/7444 Species in Soil Sample

Most of the Trichoderma species are morphologically very similar and were considered for many years as a single species. Since new species were discovered, a consolidated taxonomical scheme was needed and proposed and defined nine morphological species aggregates. DNA methods brought additional valuable criteria to the taxonomy of Trichoderma which are being used today for studies that include identification and phylogenetic classification. Most isolates of the genus Trichoderma that were found to act as mycoparasites of many economically important aerial and soil-borne plant pathogens. Trichoderma has attained importance for substitute of chemical pesticides and hence an attempt was intended to corroborate the positive relatedness of molecular and morphological characters. A fungal strain of Trichoderma longibrachiatum 28CP/7444 was isolated from a soil sample collected from Barabanki district of Uttar Pradesh, India. The universal primers were used for amplification of the 28S rRNA gene fragment and strain characterized by using 28S rRNA gene sequence with the help of ITS marker. It is proposed that the identified strain Trichoderma longibrachiatum 28CP be assigned as the type strain of a species of the genus Trichoderma based on phylogenetic tree analysis together with the 28S rRNA gene sequence search in Ribosomal Database Project, small subunit rRNA and large subunit rRNA databases. The sequence was deposited in GenBank with the accession number JX978541. Thus an integrated approach of morphological and molecular markers can be employed to identify a superior strain of Trichoderma for its commercial exploitation

Correlation of clinical, biochemical and radiological characteristics with histopathology of ovarian masses: hospital based descriptive study

Background: Ovarian cancer is an important cause of morbidity and mortality in the middle aged women. A systematic study of all ovarian tumours encountered in a large institute over a period of years is more likely to produce a significant amount of useful data regarding the clinical manifestations, the incidence of various types of ovarian tumours and the type of treatment offered. In this study we correlate various clinical presentations, ultrasound features, and various tumour marker levels with histopathology of ovarian masses.Methods: The study was conducted in the department of obstetrics and gynaecology in collaboration with department of radiology and pathology and lab medicine, Deen Dayal Upadhyay hospital from April 2015 to December 2016.Results: In the present study, 97 ovarian masses have been operated out of total 708 gynaecological surgeries in the obstetrics and gynaecology department of Deen Dayal Upadhyay hospital over the stipulated period. Prevalence of ovarian masses was 13.7%. Most of the ovarian masses were prevalent in the reproductive age group i.e. 21-40 years of age group in the present study though malignant masses were commonest in post-menopausal age group in the present study. 2 out 11 malignant ovarian masses were in the age group of 10-20 years which were dysgerminoma and immature teratoma respectively. Intra-operative findings like presence of mural nodule, haemorrhage and necrosis, ascites, papillary excrescences and omental caking were also found to have strong correlation with malignancy.Conclusions: A detailed preoperative workup and a simple tool loke RMI can differentiate between benign and malignant masses pre-operatively especially in post-menopausal women

PAPR REDUCTION IN ACO-OFDM FOR VISIBLE LIGHT COMMUNICATION SYSTEM

Visible Light Communication (VLC) is gaining popularity in optical wireless. In conventional OFDM, bi-polar signals having both positive and negative values are considered. However, in optical OFDM uni-polar signals, which have only positive values, are used. Therefore, suitable changes have to be done in conventional OFDM to make it compatible with O-OFDM. These modifications lead to the generation of asymmetrically clipped optical Orthogonal Frequency Division Multiplexing (ACO-OFDM) technology. In ACO-OFDM systems Peak to Average Power Ratio (PAPR) is a detrimental effect and should be suppressed. In ACO-OFDM, the estimation of probability density function (pdf) is not straightforward; therefore, a very limited literature is available. In this paper, an attempt is made to estimate pdf and Complimentary Cumulative Distribution Function (CCDF) expression for an ACO-OFDM with intensity modulation and direct detection (IM/DD), and its validity is checked by using simulation results. For ACO-OFDM scheme PAPR reduction methodology is used by applying various clipping strategies along with non-linear µ-law companding scheme. The results presented in the paper are obtained through computer simulation using MATLAB software. As clipping increases Bit Error Rate (BER), therefore, at various clipping mechanism BER are also obtained. It has been found, that by choosing suitable clipping along with non-linear companding scheme, PAPR can be reduced significantly while maintaining reasonable good BER performance. It is found, that with the proposed technique, PAPR is reduced by 76.10% as compared to raw ACO-OFDM

Phylogenetic diversity analysis of Trichoderma species based on internal transcribed spacer (ITS) marker

The phylogeny of Trichoderma and the phylogenetic relationships of its species was investigated by maximum parsimony analysis and distance analysis of DNA sequences from multiple genetic loci 18S rDNA sequence analysis suggests that the genus Trichoderma evolved at the same time as Hypomyces and Fusarium and thus about 110 Myr ago 28S rDNA sequence analysis shows that the genus Trichoderma is part of a monophyletic branch within the Hypocreaceae. Most isolates of the genus Trichoderma were found to act as mycoparasites of many economically important aerial and soil-borne plant pathogens. Trichoderma has attained importance as a substitute for chemical pesticides and hence an attempt was intended to corroborate the positive relatedness of molecular and morphological characters. Two fungal strains, Trichoderma koningii Tk-5201/CSAU and Trichoderma virens Tvi-4177/CSAU were isolated from a soil sample collected from CSA Farm, Kanpur district of Uttar Pradesh, India. The universal primers (internal transcribed spacer, ITS) were used for the amplification of 18S rRNA gene fragment and strains were thus characterized with the help of ITS marker. It is proposed that the identified strains T. koningii Tk-5201/CSAU and T. virens Tvi-4177/CSAU be assigned as the type strains of a species of genus Trichoderma based on phylogenetic tree analysis together with the 18S rRNA gene sequence search in Ribosomal Database Project, small subunit rRNA and large subunit rRNA databases. The sequence was deposited in GenBank with the accession numbers KC800923 and KC800924, respectively. Thus an integrated approach of morphological and molecular markers can be employed to identify a superior strain of Trichoderma for its commercial exploitation.Keywords: 18S ribosomal RNA gene, Trichoderma, phylogenetic analysis, internal transcribed spacer (ITS), DNA sequencing, GenBankAfrican Journal of Biotechnology, Vol. 13(3), pp. 449-455, 15 January, 201

Estrogen Up-regulates Apolipoprotein E (ApoE) Gene Expression by Increasing ApoE mRNA in the Translating Pool via the Estrogen Receptor α-Mediated Pathway

The antiatherogenic property of estrogens is mediated via at least two mechanisms: first by affecting plasma lipoprotein profiles, and second by affecting the components of the vessel wall. Raising plasma apolipoprotein E (apoE) in mice protects them against diet-induced atherosclerosis (Shimano, H., Yamada, N., Katsuki, M., Gotoda, T., Harada, K., Murase, T., Fukuzawa, C., Takaku, F., and Yazaka, Y. (1992) Proc. Natl. Acad. Sci. U. S. A. 89, 1750-1754). It is possible that estrogen may be antiatherogenic at least in part by increasing plasma apoE levels. Therefore, we studied the regulation of apoE by estrogen. A survey of 15 inbred strains of mice showed that some mouse strains responded to injections or subcutaneously implanted pellets of estradiol by raising their apoB and apoE levels and some did not. We performed detailed studies in two "responder" strains, C57L and C57BL, and two "non-responder" strains, C3H and BALBc. Responders increased their plasma apoE levels 2.5-fold. Non-responders' levels were altered +/-10%. In the responders the distribution of apoE among the plasma lipoproteins shifted from high density lipoprotein toward the apoB-containing lipoprotein fractions. In nonresponders the shift was toward high density lipoprotein. Hepatic apoE mRNA levels and relative rates of apoE mRNA transcription were unchanged in all strains, suggesting that apoE regulation occurred at posttranscriptional loci. Therefore, we measured apoE synthesis in fresh liver slices and on isolated hepatic polysomes. Two-fold increases were noted but only in responders accompanied by selective 1.5-fold increases in polysomal apoE mRNA levels. Similar increases in apoE synthesis were also observed in castrated C57BL mice given either physiological or pharmacological replacement doses of estradiol, but not testosterone, suggesting that the effect of estradiol was specific on the distribution of apoE mRNA in the translationally active polysomal pool. Next, we examined whether the effects of estrogen on apoE translation were mediated by estrogen receptors (ER). ER-alpha knock-out mice and their wild-type littermates were administered estradiol. As expected, apoE levels and hepatic apoE synthesis increased more than 2-fold in the wild-type littermates, but only 20% increases in the plasma apoE and hepatic synthesis were observed in the ER knock-out mice. Hepatic apoE mRNA levels did not change in either the wild-type or the ER knock-out mice. Thus, estradiol up-regulates apoE gene expression by increasing levels of apoE mRNA in the polysomal translating pool. Furthermore, the increased polysomal recruitment of apoE mRNA is largely mediated by estrogen receptors

Lack of Correlation of Plasma HDL With Fecal Cholesterol and Plasma Cholesterol Efflux Capacity Suggests Importance of HDL Functionality in Attenuation of Atherosclerosis

A number of clinical findings suggested HDL-raising as a plausible approach to treat residual risk of CVD. However, lack of CVD risk reduction by elevated HDL cholesterol (HDL-C) through cholesterol ester transfer protein (CETP) inhibition and enhanced risk reduction in apolipoprotein A-I Milano (apoAI-M) individuals with low HDL-C shifted the focus from HDL-C level to HDL function. In the present study, we investigated correlations between HDL-C, HDL function, fecal cholesterol excretion, and ex vivo plasma cholesterol efflux capacity (CEC) in animal models using two HDL modulators, LXR and PPAR-α agonists. In C57Bl mice, LXR agonist, T1317, raised HDL-C by 30%, while PPAR-α agonist, fenofibrate, reduced HDL-C by 30%, but fecal cholesterol showed twofold increase in both cases. CEC showed a 30–40% increase. Combination of LXR and PPAR-α agonists showed no changes in HDL-C, but, interestingly, fecal cholesterol increased by 4.5-fold, and CEC by 40%, suggesting existence of additional pathway for fecal cholesterol excretion. Regression analysis showed a lack of correlation between HDL-C and fecal cholesterol and CEC, while fecal cholesterol showed significant correlation with CEC, a measure of HDL function. ABCA1 and G1, the two important players in RCT showed greater induction with LXR agonist than PPAR-α agonist. HDL-C increased by 40 and 80% in LXR and PPAR-α treated apoA-I transgenic mice, respectively, with 80% increase in fecal cholesterol. A fivefold increase in fecal cholesterol with no correlation with either plasma HDL-C or CEC following co-treatment with LXR and PPAR-α agonists suggested existence of an HDL-independent pathway for body cholesterol elimination. In hyperlipidemic diabetic ob/ob mice also combination of LXR and PPAR-α agonists showed marked increases in fecal cholesterol content (10–20-fold), while HDL-C rise was only 40%, further suggesting HDL-independent elimination of body cholesterol in mice treated with combination of LXR and PPAR-α agonists. Atherosclerosis attenuation by LXR and PPAR-α agonists in LDLr-deficient mice was associated with increased fecal cholesterol, but not HDL-C. However, fecal cholesterol counts showed inverse correlation with aortic cholesteryl ester content. These data suggest: (a) lack of correlation between HDL-C and fecal or aortic cholesterol content; (b) HDL function (CEC) correlated with fecal cholesterol content; (c) association of reduced aortic lipids in LDLr−/− mice with increased fecal cholesterol, but not with HDL-C, and (d) existence of an HDL-independent pathway for fecal cholesterol excretion following co-treatment with LXR and PPAR-α agonists

Theoretical Investigation of Different Diversity Combining Techniques in Cognitive Radio, Journal of Telecommunications and Information Technology, 2018, nr 3

In this paper, the performance of an energy detector in cognitive radio, using different diversity combining techniques, is evaluated. Among many diversity combining techniques, maximal ratio combining (MRC) gives the best results but at the cost of the highest complexity. To design a simpler receiver, it is suggested to use less complex combining techniques, i.e. switched diversity, which provides one of the least complex solutions to combat fading. The paper analyzes two switched diversity schemes, switch examine combining (SEC), and switch examine combining with post examining selection (SECp). A closed form expression determining the probability of detection using MRC, SEC and SECp is derived for various numbers of branches. Detection performance with different diversity combining techniques is compared and the complexity trade-off is observed