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61.
Plasma triglyceride (TG) concentration is reemerging as an important cardiovascular disease risk factor. More complete understanding of the genes and variants that modulate plasma TG should enable development of markers for risk prediction, diagnosis, prognosis, and response to therapies and might help specify new directions for therapeutic interventions. Recent genome-wide association studies (GWAS) have identified both known and novel loci associated with plasma TG concentration. However, genetic variation at these loci explains only ~10% of overall TG variation within the population. As the GWAS approach may be reaching its limit for discovering genetic determinants of TG, alternative genetic strategies, such as rare variant sequencing studies and evaluation of animal models, may provide complementary information to flesh out knowledge of clinically and biologically important pathways in TG metabolism. Herein, we review genes recently implicated in TG metabolism and describe how some of these genes likely modulate plasma TG concentration. We also discuss lessons regarding plasma TG metabolism learned from various genomic and genetic experimental approaches. Treatment of patients with moderate to severe hypertriglyceridemia with existing therapies is often challenging; thus, gene products and pathways found in recent genetic research studies provide hope for development of more effective clinical strategies.  相似文献   
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63.
Fish scales, which are hitherto discarded as waste, were collected and cleaned thoroughly. The scales were hydrolyzed under controlled acidic conditions, neutralized and made in to a sheet, i.e., fish scale collagen sheet (FCS). The FCS was characterized for its infrared spectroscopy (IR), thermo-gravimetric analysis (TGA), scanning electron microscopy (SEM), and mechanical properties. The IR study has shown that the sheet contains both organic and inorganic phases revealing that the scales are partially deminaralized. The tensile strength of FCS is enough if it is used as a wound dressing material. The SEM studies have shown that FCS is porous and exhibited fibrous nature.  相似文献   
64.
Agrobacterium-mediated transformation of rice was done using the binary vector pNSP3, harbouring the rice chitinase (chi11) gene under maize ubiquitin promoter and the tobacco β-1,3-glucanase gene under CaMV 35S promoter in the same T-DNA. Four of the six T0 plants had single copies of complete T-DNAs, while the other two had complex integration patterns. Three of the four single-copy lines showed a 3:1 segregation ratio in the T1 generation. Northern and western blot analyses of T1 plants revealed constitutive expression of chitinase and β-1,3-glucanase genes. Homozygous T2 plants of the single-copy lines CG20, CG27 and CG53 showed 62-, 9.6- and 11-fold higher chitinase activity over the control plants. β-1,3-Glucanase activity was 1.1- to 2.5-fold higher in the transgenic plants. Bioassay of homozygous T2 plants of the three single-copy transgenic lines against Rhizoctonia solani revealed a 60% reduction in sheath blight Disease Index in the first week. The Disease Index increased from 61.8 in the first week to 90.6 in the third week in control plants, while it remained low (26.8–34.2) in the transgenic T3 plants in the corresponding period, reflecting the persistence of sheath blight resistance for a longer period.  相似文献   
65.
An Internet computing server has been developed to identify all the occurrences of the internal sequence repeats in a protein and DNA sequences. Further, an option is provided for the users to check the occurrence(s) of the resultant sequence repeats in the other sequence and structure (Protein Data Bank) databases. The databases deployed in the proposed computing engine are up-to-date and thus the users will get the latest information available in the respective databases. The server is freely accessible over the World Wide Web (WWW). AVAILABILITY: http://bioserver1.physics.iisc.ernet.in/fair/  相似文献   
66.
V Sekar  B C Carlton 《Gene》1985,33(2):151-158
A transformant of Bacillus megaterium, VB131, was isolated which carries a 6.3-kb XbaI segment of the crystal toxin gene of Bacillus thuringiensis var. israelensis (BTI) cloned in a vector plasmid pBC16 to yield pVB131. The chimeric plasmid DNA from VB131 was introduced into a transformable Bacillus subtilis strain by competence transformation. Both the B. megaterium VB131 strain and the B. subtilis strain harboring the chimeric plasmid produced irregular, parasporal, phase-refractile, crystalline inclusions (Cry+) during sporulation. The sporulated cells as well as the isolated crystal inclusions of the pVB131-containing B. megaterium and B. subtilis strains were highly toxic to the larvae of Aedes aegypti. Also, the solubilized crystal protein preparation from VB131[pVB131] showed clear immuno cross-reaction with antiserum to the BTI crystal toxin. 32P-labeled pVB131 plasmid DNA showed specific hybridization with a 112-kb plasmid DNA of Cry+ strains of BTI, and no hybridization with other plasmid or chromosomal DNA of either Cry+ or Cry- variants. These results are in agreement with our previous findings (González and Carlton, 1984) that the 112-kb plasmid of BTI is associated with the production of the crystal toxin.  相似文献   
67.
Tuberculosis is a significant problem globally for domestic animals as well as captive and free ranging wild life. Rapid point of care (POC) serology kits are well suited for the diagnosis of TB in wild animals. However, wild animals are invariably exposed to environmental non-pathogenic mycobacterium species with the development of cross reacting antibodies. In the present study, POC TB diagnosis kit was developed using a combination of pathogenic Mycobacteria specific recombinant antigens and purified protein derivatives of pathogenic and non-pathogenic Mycobacteria. To benchmark the TB antibody detection kit, particularly in respect to specificity which could not be determined in wildlife due to the lack of samples from confirmed uninfected animals, we first tested well-characterized sera from 100 M. bovis infected and 100 uninfected cattle. Then we investigated the kit’s performance using sera samples from wildlife, namely Sloth Bears (n = 74), Elephants (n = 9), Cervidae (n = 14), Felidae (n = 21), Cape buffalo (n = 2), Wild bear (n = 1) and Wild dog (n = 1).In cattle, a sensitivity of 81% and a specificity of 90% were obtained. The diagnostic sensitivity of the kit was 94% when the kit was tested using known TB positive sloth bear sera samples. 47.4% of the in-contact sloth bears turned seropositive using the rapid POC TB diagnostic kit. Seropositivity in other wild animals was 25% when the sera samples were tested using the kit. A point of care TB sero-diagnostic kit with the combination of proteins was developed and the kit was validated using the sera samples of wild animals.  相似文献   
68.
The highest values of consanguinity was found among “Kamma” (45.0%), “Ediga” (47.5%) and “Mala” (55.7%) who occupy different strata of Indian caste hierarchy. In the way of searchout the factors influencing consanguineous marriages, the present paper finda the negative relationship between educational levels of the spouses and consanguinity. The educational levels of men has significant effect on the frequency of consanguinious marriages among “Kamma” and “Mala”. However, further analysis deplore significant differences in the mean levels consanguinity between educational groups. It divulge low level of higher education among the populations. Only 12% of men and 1.6% of women have degree level and above education in the total sample.  相似文献   
69.
Computational genomic analysis of hemorrhagic fever viruses   总被引:6,自引:0,他引:6  
A number of distinct viruses are known as hemorrhagic fever viruses based on a shared ability to induce hemorrhage by poorly understood mechanisms, typically involving the formation of blood clots (“disseminated intravascular coagulation”). It is well documented that selenium plays a significant role in the regulation of blood clotting via its effects on the thromboxane/prostacyclin ratio, and effects on the complement system. Selenium has an anticlotting effect, whereas selenium deficiency has a proclotting or thrombotic effect. It is also well documented that extreme dietary selenium deficiency, which is almost never seen in humans, has been associated with hemorrhagic effects in animals. Thus, the possibility that viral selenoprotein synthesis might contribute to hemorrhagic symptoms merits further consideration. Computational genomic analysis of certain hemorrhagic fever viruses reveals the presence of potential protein coding regions (PPCRs) containing large numbers of in-frame UGA codons, particularly in the −1 reading frame. In some cases, these clusterings of UGA codons are very unlikely to have arisen by chance, suggesting that these UGAs may have some function other than being a stop codon, such as encoding selenocysteine. For this to be possible, a downstream selenocysteine insertion element (SECIS) is required. Ebola Zaire, the most notorious hemorrhagic fever virus, has a PPCR with 17 UGA codons, and several potential SECIS elements can be identified in the viral genome. One potential viral selenoprotein may contain up to 16 selenium atoms per molecule. Biosynthesis of this protein could impose an unprecedented selenium demand on the host, potentially leading to severe lipid peroxidation and cell membrane destruction, and contributing to hemorrhagic symptoms. Alternatively, even in the absence of programmed selenoprotein synthesis, it is possible that random slippage errors would lead to increased encounters with UGA codons in overlapping reading frames, and thus potentially to nonspecific depletion of SeC in the host.  相似文献   
70.
M C Sekar  B D Roufogalis 《Life sciences》1984,35(14):1527-1533
The effects of muscarinic and alpha-adrenergic receptor stimulation on phosphoinositide turnover in rat atria have been compared. Despite the similar densities of muscarinic receptors in rat left and right atria, 0.1 mM carbachol increased [32P]phosphate incorporation into phosphatidylinositol (PI) by 35% (p less than 0.05) in left atria but had no effect in right atria. By contrast to the small muscarinic receptor effect, stimulation of alpha 1-adrenergic receptors by 0.1 mM methoxamine produced a more than two fold increase in [32P]phosphate incorporation into PI in both left and right atria, despite the reported smaller density of alpha-adrenergic receptors in rat atria compared to muscarinic receptors. Enhanced phosphate labelling by methoxamine did not occur in phospholipids other than PI, and was blocked by the alpha-adrenergic antagonist, phentolamine (20 microM). The results indicate that the majority of the muscarinic receptors in rat atria are not coupled to phosphoinositide turnover. If indeed the observed enhancement in [32P]-phosphate labelling by carbachol reflects phosphoinositide turnover, and assuming equal coupling efficiencies of muscarinic and adrenergic receptors, it is calculated that not more than 2% of the muscarinic receptors in rat left atria are coupled to this response.  相似文献   
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