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261.
Herpes simplex virus 2 (HSV-2) is the primary cause of genital herpes, which is one of the most common sexually transmitted viral infections worldwide and a major cofactor for human immunodeficiency virus infection. The lack of an effective vaccine or treatment and the emergence of drug-resistant strains highlight the need for developing new antivirals for HSV-2. Here, we demonstrate that a low-molecular-weight peptide isolated against 3-O-sulfated heparan sulfate (3-OS HS) can efficiently block HSV-2 infection. Treatment with the peptide inhibited viral entry and cell-to-cell spread both in vitro and in vivo using a mouse model of genital HSV-2 infection. Quite interestingly, the peptide showed a preferential binding to HSV-2-infected cells, with more than 200% increased binding compared to uninfected cells. Our additional results show that heparan sulfate expression is upregulated by 25% upon HSV-2 infection, which is a significant new finding that could be exploited for designing new diagnostic tests and treatment strategies against HSV-2-infected cells. In addition, our results also raise the possibility that 3-OS HS modifications within HS may be upregulated even more to accommodate for a significantly higher increase in the peptide binding to the infected cells. 相似文献
262.
Lemas DJ Wiener HW O'Brien DM Hopkins S Stanhope KL Havel PJ Allison DB Fernandez JR Tiwari HK Boyer BB 《Journal of lipid research》2012,53(1):175-184
Variants of carnitine palmitoyltransferase 1A (CPT1A), a key hepatic lipid oxidation enzyme, may influence how fatty acid oxidation contributes to obesity and metabolic outcomes. CPT1A is regulated by diet, suggesting interactions between gene variants and diet may influence outcomes. The objective of this study was to test the association of CPT1A variants with body composition and lipids, mediated by consumption of polyunsaturated fatty acids (PUFA). Obesity phenotypes and fasting lipids were measured in a cross-sectional sample of Yup'ik Eskimo individuals (n = 1141) from the Center of Alaska Native Health Research (CANHR) study. Twenty-eight tagging CPT1A SNPs were evaluated with outcomes of interest in regression models accounting for family structure. Several CPT1A polymorphisms were associated with HDL-cholesterol and obesity phenotypes. The P479L (rs80356779) variant was associated with all obesity-related traits and fasting HDL-cholesterol. Interestingly, the association of P479L with HDL-cholesterol was still significant after correcting for body mass index (BMI), percentage body fat (PBF), or waist circumference (WC). Our findings are consistent with the hypothesis that the L479 allele of the CPT1A P479L variant confers a selective advantage that is both cardioprotective (through increased HDL-cholesterol) and associated with reduced adiposity. 相似文献
263.
De-embryonated cotyledon explants of peanut were co-cultivated under different conditions with Agrobacterium tumefaciens harbouring pIG121hm plasmid carrying intron-containing β-glucuronidase as a reporter while hygromycin phosphotransferase and neomycin phosphotransferase as selectable marker genes.
Co-cultivation duration and temperature, various antioxidants and their concentrations, bacterial strains and explant characteristics
(incised and non-incised) were examined either alone or in combinations for optimization of transient expression of the reporter
gene. Up to 81% transformation was recorded when non-incised explants were co-cultivated with strain EHA101 for 5 days at
21°C on shoot induction medium containing 100 mg/L l-cysteine. Addition of the optimized concentration of augmentin (200 mg/L) along with cefotaxime (200 mg/L) to the shoot induction
medium not only effectively eliminated bacterial growth, but also facilitated high frequency of shoot induction. The 40 mg/L
hygromycin concentration prevented complete shoot regeneration of non-transgenic explants thus considered for the regeneration
of transgenics. Resistant shoots were successfully transferred to soil either by grafting or in vitro rooting. Survival rate
of the grafted shoots was nearly 100% in glass-house conditions. The optimized protocol took around 3 months to generate healthy
plants. Polymerase chain reaction, Southern blot hybridization, histochemical tests, segregation and hygromycin-leaf assays
of selected transgenic plants showed integration of the transgene into peanut genome. No chimeras were noticed during the
study. 相似文献
264.
265.
In vitro regeneration of Trifolium glomeratum, a leguminous forage species, was attempted through leaf, petiole, cotyledon, hypocotyl, collar and root explants and two
media combinations. Root and collar explants showed no callus induction. Medium with 0.05 mg dm−3 α-naphthaleneacetic acid (NAA) and 0.10 mg dm−3 N6-benzyladenine (BA) was more effective for hypocotyl explant whereas cotyledon and petiole explant were more responsive to
5.0 mg dm−3 NAA and 1.0 mg dm−3 BA. Friable, green calli obtained from petiole explant on this medium showed organogenetic potential. Modified root-inducing
medium having 0.21 mg dm−3 indole-3-acetic acid and 2.5 % sucrose was successful for root induction and plantlets were successfully transferred to field
after hardening and Rhizobium inoculation. 相似文献
266.
267.
Synthesis and antibacterial activity of substituted 1,2,3,4-tetrahydropyrazino [1,2-a] indoles 总被引:1,自引:0,他引:1
Tiwari RK Singh D Singh J Yadav V Pathak AK Dabur R Chhillar AK Singh R Sharma GL Chandra R Verma AK 《Bioorganic & medicinal chemistry letters》2006,16(2):413-416
A series of substituted 1,2,3,4-tetrahydropyrazino [1,2-a] indole derivatives have been synthesized and tested against the Gram positive and Gram negative strains of bacteria namely Staphylococcus aureus (MTCCB 737), Salmonella typhi (MTCCB 733), Pseudomonas aeruginosa (MTCCB 741), Streptomyces thermonitrificans (MTCCB 1824) and Escherichia coli (MTCCB 1652). All synthesized compounds showed mild to moderate activity. However, compounds 4d-f were found to have potent activity against pathogenic bacteria used in the study. Their MIC ranged from 3.75 to 60 microg/disc. In vitro toxicity tests demonstrated that toxicity of 4d-f was not significantly different than that of gentamycin. However, at higher concentration (1000-4000 microg/ml) difference was highly significant. 相似文献
268.
Kumar VS Sharma VL Tiwari P Singh D Maikhuri JP Gupta G Singh MM 《Bioorganic & medicinal chemistry letters》2006,16(9):2509-2512
The study investigated spermicidal and antitrichomonas activities of selective serotonin reuptake inhibitor (SSRI) antidepressants with a view to generate new lead for development of dual-function spermicidal microbicides, which is an urgent global need. Fluoxetine, Sertraline, and Fluvoxamine exhibited both spermicidal and anti-STI (antitrichomonas) activities in vitro, whereas Paroxetine and Citalopram showed only the spermicidal activity. Fluoxetine exhibited better activity profile than the other antidepressant drugs with its spermicidal and antitrichomonas activities being comparable to that of the OTC contraceptive Nonoxynol-9. The non-detergent nature of Fluoxetine and a much lower spermicidal ED50 value (than N-9) may add considerably to its merit as a candidate for microbicidal contraceptive. Thus, the antidepressants exhibiting both spermicidal and antitrichomonas activities might provide useful lead for the development of novel, dual-function spermicidal contraceptives. 相似文献
269.
Gudewar J Pan D Bera AK Das SK Konar A Rao JR Tiwari AK Bhattacharya D 《Molecular biology reports》2009,36(6):1381-1385
Sixty-six isolates of larval stage of Echinococcus granulosus, a known pathogenic parasite of man and animals were collected from cattle, buffalo, sheep, and goats. Single-stranded conformation
polymorphism (SSCP) for analysis of variation after denaturation of amplicon of intron of actin II (ACTII) revealed six SSCP
phenotypes. Intron portion was analyzed considering introns-early and introns-late theories. Isolates belonging to different
conformers were further screened for mitochondrial ATPase subunit 6 (ATP6) and NADH dehydrogenase subunit II (nadII) genotypes. Assignment of each isolate to its specific strain was achieved after comparing with standard genotypes of E. granulosus. Variants deduced by nuclear targets did not match with mitochondrial haplotypes. A possible explanation for this observation
can be attributed toward interspecific hybridization since cross-fertilization occurs less frequently in hermaphrodite organisms.
A phylogenetic tree drawn on the basis of predicted aminoacid sequence of ATP6 and nadII revealed two distinct clusters i.e. E. granulosus sensu stricto and E. ortleppi/cattle strain (EG5). To the best of our knowledge, this is the first report of genetic characterization of two distinct ATP6
and nadII genotypes of zoonotic importance living in sympatry. 相似文献
270.
R. Ranga Rao Ashok K. Tiwari P. Prabhakar Reddy K. Suresh Babu Amtul Z. Ali K. Madhusudana J. Madhusudana Rao 《Bioorganic & medicinal chemistry》2009,17(14):5170-5175
A bioassay-guided fractionation and chemical examination of antihyperglycemic root extract of Derris indica resulted in isolation and characterization of two new furanoflavanoids (1, 2) along with thirteen known compounds (3–15). Their structures were determined on the basis of extensive spectroscopic (IR, MS, 1D and 2D NMR) data analysis and by comparison with the literature data. All the compounds were tested in vitro for intestinal α-glucosidase inhibitory and DPPH radical activity. New compounds (1, 2) displayed moderate intestinal α-glucosidase inhibitory as well as free radical scavenging activity. Other compounds also displayed varying degrees of moderate intestinal α-glucosidase inhibitory activity. Pongamol (6) displayed potent intestinal α-glucosidase inhibition. 相似文献