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1.
Recent achievements in the whole-genome sequencing especially viral and bacterial ones together with the development of methods of bioinformatics and molecular biology, have created preconditions for transition from synthesis of genes to assembly of the whole genomes based on chemically synthesized blocks, oligonucleotides. The creation of artificial genomes and artificial cells will undoubtedly render huge influence on a deepening of knowledge on mechanisms of functioning of living systems at a cellular level, on a way of origin and evolution of life, and also on biotechnology of the future, and will generate preconditions for the further development of synthetic biology and nanobiotechnology.  相似文献   
2.
Human adenovirus has evolved to infect and replicate in terminally differentiated human epithelial cells, predominantly those within the airway, the gut, or the eye. To overcome the block to viral DNA replication present in these cells, the virus expresses the Early 1A proteins (E1A). These immediate early proteins drive cells into S-phase and induce expression of all other viral early genes. During infection, several E1A isoforms are expressed with proteins of 289, 243, 217, 171, and 55 residues being present for human adenovirus type 5. Here we examine the contribution that the two largest E1A isoforms make to the viral life cycle in growth-arrested normal human fibroblasts. Viruses that express E1A289R were found to replicate better than those that do not express this isoform. Importantly, induction of several viral genes was delayed in a virus expressing E1A243R, with several viral structural proteins undetectable by western blot. We also highlight the changes in E1A isoforms detected during the course of viral infection. Furthermore, we show that viral DNA replication occurs more efficiently, leading to higher number of viral genomes in cells infected with viruses that express E1A289R. Finally, induction of S-phase specific genes differs between viruses expressing different E1A isoforms, with those having E1A289R leading to, generally, earlier activation of these genes. Overall, we provide an overview of adenovirus replication using modern molecular biology approaches and further insights into the contribution that E1A isoforms make to the life cycle of human adenovirus in arrested human fibroblasts.  相似文献   
3.
Polymorphism of 11 microsatellite DNA loci was analysed in Polish Red (PR), Hereford and Holstein-Friesian (HF) cattle raised in Poland and genetic distance among these breeds was determined. At the 11 loci (TGLA227, BM2113, TGLA53, ETH10, SPS115, TGLA126, TGLA122, INRA23, ETH3, ETH225 and BM1824) analysed with automated DNA sizing technology, a total of 213 alleles were identified: 76 in PR, 76 in HF, and 61 in Hereford. All the microsatellite DNA markers showed high polymorphism. Polymorphism information content (PIC) calculated for each marker exceeded 0.5, except for the ETH3 locus in Hereford cattle (PIC=0.475), and heterozygosity (H) ranged from 54.1% to as much as 85.2%. The coefficient of genetic distance was 0.354 between PR and Hereford, 0.414 between HF and Hereford, and 0.416 between PR and HF cattle.  相似文献   
4.
Emerging evidence suggests that renal endothelial function may be altered in ischemia-reperfusion injury. Acute kidney injury is sexually dimorphic, and estrogen protects renal tubular function after experimental ischemic injury. This study tested the hypothesis that during ischemia-reperfusion, estrogen alters glomerular endothelial function to prevent hyperpermeability. Glomerular endothelial cells were exposed to 8-h oxygen-glucose deprivation (OGD) followed by 4- and 8-h reoxygenation-glucose repletion. After 4-h reoxygenation-glucose repletion, transendothelial permeability to Ficoll-70 was reduced, and transendothelial resistance increased, by 17β-estradiol vs. vehicle treatment during OGD (OGD-vehicle: 91.0 ± 11.8%, OGD-estrogen: 102.6 ± 10.8%, P < 0.05). This effect was reversed by coadministration of G protein-coupled receptor 30 (GPR30) antagonist G15 with 17β-estradiol (OGD-estrogen-G15: 89.5 ± 6.9, P < 0.05 compared with 17β-estradiol). To provide preliminary confirmation of this result in vivo, Ficoll-70 was administered to mice 24 h after cardiac arrest and cardiopulmonary resuscitation (CA/CPR). Blood urea nitrogen (BUN) and serum creatinine (SCr) in these mice were elevated within 12 h following CA/CPR and reduced at 24 h by pretreatment with 17β-estradiol (BUN/SCr 17β-estradiol: 34 ± 19/0.2 ± 0.1 vehicle: 92 ± 49/0.5 ± 0.3, n = 8-12, P < 0.05). Glomerular sieving of Ficoll 70 was increased by CA/CPR within 2 h of injury and 17β-estradiol treatment (θ; 17β-estradiol: 0.74 ± 0.26 vs. vehicle: 1.05 ± 0.53, n = 14-15, P < 0.05). These results suggest that estrogen reduces postischemic glomerular endothelial hyperpermeability at least in part through GPR30 and that estrogen may regulate post CA/CPR glomerular permeability in a similar fashion in vivo.  相似文献   
5.
Male gender is a risk factor for progression of polycystic kidney disease (PKD). 17β-Estradiol (E2) protects experimentally, but clinical use is limited by adverse effects. Novel E2 metabolites provide many benefits of E2 without stimulating the estrogen receptor, and thus may be safer. We hypothesized that E2 metabolites are protective in a model of PKD. Studies were performed in male control Han:SPRD rats, and in cystic males treated with orchiectomy, 2-methoxyestradiol, 2-hydroxyestradiol (2-OHE), or vehicle, from age 3 to 12 wk. Cystic rats exhibited renal functional impairment (~50% decrease in glomerular filtration and renal plasma flow rates, P < 0.05) and substantial cyst development (20.5 ± 2.0% of cortex area). 2-OHE was the most effective in limiting cysts (6.0 ± 0.7% of cortex area, P < 0.05 vs. vehicle-treated cystic rats) and preserving function, in association with suppression of proliferation, apoptosis, and angiogenesis markers. Downregulation of p21 expression and increased expression of Akt, the mammalian target of rapamycin (mTOR), and some of its downstream effectors were significantly reversed by 2-OHE. Thus, 2-OHE limits disease progression in a cystic rodent model. Mechanisms include reduced renal cell proliferation, apoptosis, and angiogenesis. These effects may be mediated, at least in part, by preservation of p21 and suppression of Akt and mTOR. Estradiol metabolites may represent a novel, safe intervention to slow progression of PKD.  相似文献   
6.
7.
Utilization of capillary electrophoresis (CE) for characterization and analytical separation of submicron- and micron-sized organic and inorganic particles as well as biological vesicles is reviewed. CE has been applied to charged polystyrene size standards, inorganic and organic colloidal particles, lipoprotein particles, liposomes, microsomes and viruses. These particle separations generally occur in a size-dependent manner and provide values of electrophoretic mobility which are in good agreement with those obtained by other electrophoretic techniques.  相似文献   
8.
Russian Journal of Bioorganic Chemistry - The synthesis of deoxyuridine triphosphate derivatives with alkyl groups of various chain length attached to the pyrimidine base by the trans-alkene linker...  相似文献   
9.
The factors that determine the characteristic seasonality of influenza remain enigmatic. Current models predict that occurrences of influenza outside the normal surveillance season within a temperate region largely reflect the importation of viruses from the alternate hemisphere or from equatorial regions in Asia. To help reveal the drivers of seasonality we investigated the origins and evolution of influenza viruses sampled during inter-seasonal periods in Australia. To this end we conducted an expansive phylogenetic analysis of 9912, 3804, and 3941 hemagglutinnin (HA) sequences from influenza A/H1N1pdm, A/H3N2, and B, respectively, collected globally during the period 2009-2014. Of the 1475 viruses sampled from Australia, 396 (26.8% of Australian, or 2.2% of global set) were sampled outside the monitored temperate influenza surveillance season (1 May – 31 October). Notably, rather than simply reflecting short-lived importations of virus from global localities with higher influenza prevalence, we documented a variety of more complex inter-seasonal transmission patterns including “stragglers” from the preceding season and “heralds” of the forthcoming season, and which included viruses sampled from clearly temperate regions within Australia. We also provide evidence for the persistence of influenza B virus between epidemic seasons, in which transmission of a viral lineage begins in one season and continues throughout the inter-seasonal period into the following season. Strikingly, a disproportionately high number of inter-seasonal influenza transmission events occurred in tropical and subtropical regions of Australia, providing further evidence that climate plays an important role in shaping patterns of influenza seasonality.  相似文献   
10.
Adrenergic stimulation is important for osteoclast differentiation and bone resorption. Previous research shows that this happens through β2‐adrenergic receptor (AR), but there are conflicting evidence on presence and role of α2A‐AR in bone. The aim of this study was to investigate the presence of α2A‐AR and its involvement in neuro‐endocrine signalling of bone remodelling in humans. Real‐time polymerase chain reaction (PCR) and immunohistochemistry were used to investigate α2A‐AR receptor presence and localization in bone cells. Functionality of rs553668 and rs1800544 single nucleotide polymorphism SNPs located in α2A‐AR gene was analysed by qPCR expression on bone samples and luciferase reporter assay in human osteosarcoma HOS cells. Using real‐time PCR, genetic association study between rs553668 A>G and rs1800544 C>G SNPs and major bone markers was performed on 661 Slovenian patients with osteoporosis. α2A‐AR is expressed in osteoblasts and lining cells but not in osteocytes. SNP rs553668 has a significant influence on α2A‐AR mRNA level in human bone samples through the stability of mRNA. α2A‐AR gene locus associates with important bone remodelling markers (BMD, CTX, Cathepsin K and pOC). The results of this study are providing comprehensive new evidence that α2A‐AR is involved in neuro‐endocrine signalling of bone turnover and development of osteoporosis. As shown by our results the neurological signalling is mediated through osteoblasts and result in bone resorption. Genetic study showed association of SNPs in α2A‐AR gene locus with bone remodelling markers, identifying the individuals with higher risk of development of osteoporosis.  相似文献   
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