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排序方式: 共有443条查询结果,搜索用时 31 毫秒
31.
Expression of IFI 16 in epithelial cells and lymphoid tissues 总被引:3,自引:1,他引:2
32.
Minutolo F Bertini S Betti L Danesi R Gervasi G Giannaccini G Papi C Placanica G Barontini S Rapposelli S Macchia M 《Bioorganic & medicinal chemistry letters》2003,13(24):4405-4408
Phosphonoacetamido(oxy) groups have proven to be good mimics of the diphosphate portion in geranylgeranyl protein transferase I (GGTase I) inhibitors. The introduction of small alkyl groups (Me, Et) into the diphosphate mimic moiety caused a further decrease in collateral farnesyl protein transferase (FTase) inhibitory activity, thereby improving GGTase I over FTase selectivity. 相似文献
33.
Functional Analysis of the Core Human Immunodeficiency Virus Type 1 Packaging Signal in a Permissive Cell Line 总被引:7,自引:5,他引:2
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Geoffrey P. Harrison Gino Miele Eric Hunter Andrew M. L. Lever 《Journal of virology》1998,72(7):5886-5896
Packaging of type C retrovirus genomic RNAs into budding virions requires a highly specific interaction between the viral Gag precursor and unique cis-acting packaging signals on the full-length RNA genome, allowing the selection of this RNA species from among a pool of spliced viral RNAs and similar cellular RNAs. This process is thought to involve RNA secondary and tertiary structural motifs since there is little conservation of the primary sequence of this region between retroviruses. To confirm RNA secondary structures, which we and others have predicted for this region, disruptive, compensatory, and deletion mutations were introduced into proviral constructs, which were then assayed in a permissive cell line. Disruption of either of two predicted stem-loops was found to greatly reduce RNA encapsidation and replication, whereas compensatory mutations restoring base pairing to these stem-loops had a wild-type phenotype. A GGNGR motif was identified in the loops of three hairpins in this region. Results were consistent with the hypothesis that the process of efficient RNA encapsidation is linked to dimerization. Replication and encapsidation were shown to occur at a reduced rate in the absence of the previously described kissing hairpin motif. 相似文献
34.
Manfred Accrombessi Sma?la Ouédraogo Gino Cédric Agbota Raquel Gonzalez Achille Massougbodji Clara Menéndez Michel Cot 《PloS one》2015,10(6)
Background
Anaemia is an increasingly recognized health problem in Africa, particularly in infants and pregnant women. Although malaria is known to be the main risk factor of anaemia in both groups, the consequences of maternal factors, particularly malaria in pregnancy (MiP), on infant haemoglobin (Hb) concentrations during the first months of life are still unclear.Methods
We followed-up a cohort of 1005 Beninese pregnant women from the beginning of pregnancy until delivery. A subsample composed of the first 400 offspring of these women were selected at birth and followed until the first year of life. Placental histology and blood smear at 1st clinical antenatal visit (ANC), 2nd ANC and delivery were used to assess malaria during pregnancy. Infant Hb concentrations were measured at birth, 6, 9 and 12 months of age. A mixed multi-level model was used to assess the association between MiP and infant Hb variations during the first 12 months of life.Results
Placental malaria (difference mean [dm] = - 2.8 g/L, 95% CI [-5.3, -0.3], P = 0.03) and maternal peripheral parasitaemia at delivery (dm = - 4.6 g/L, 95% CI [-7.9, -1.3], P = 0.007) were the main maternal factors significantly associated with infant Hb concentrations during the first year of life. Poor maternal nutritional status and malaria infection during infancy were also significantly associated with a decrease in infant Hb.Conclusion
Antimalarial control and nutritional interventions before and during pregnancy should be reinforced to reduce specifically the incidence of infant anaemia, particularly in Sub-Saharan countries. 相似文献35.
Michael P. Lerario Gino Gialdini Daniel M. Lapidus Mesha M. Shaw Babak B. Navi Alexander E. Merkler Gregory Y. H. Lip Jeff S. Healey Hooman Kamel 《PloS one》2015,10(12)
Background
We aimed to estimate the risk of ischemic stroke after intracranial hemorrhage in patients with atrial fibrillation.Materials and Methods
Using discharge data from all nonfederal acute care hospitals and emergency departments in California, Florida, and New York from 2005 to 2012, we identified patients at the time of a first-recorded encounter with a diagnosis of atrial fibrillation. Ischemic stroke and intracranial hemorrhage were identified using validated diagnosis codes. Kaplan-Meier survival statistics and Cox proportional hazard analyses were used to evaluate cumulative rates of ischemic stroke and the relationship between incident intracranial hemorrhage and subsequent stroke.Results
Among 2,084,735 patients with atrial fibrillation, 50,468 (2.4%) developed intracranial hemorrhage and 89,594 (4.3%) developed ischemic stroke during a mean follow-up period of 3.2 years. The 1-year cumulative rate of stroke was 8.1% (95% CI, 7.5–8.7%) after intracerebral hemorrhage, 3.9% (95% CI, 3.5–4.3%) after subdural hemorrhage, and 2.0% (95% CI, 2.0–2.1%) in those without intracranial hemorrhage. After adjustment for the CHA2DS2-VASc score, stroke risk was elevated after both intracerebral hemorrhage (hazard ratio [HR], 2.8; 95% CI, 2.6–2.9) and subdural hemorrhage (HR, 1.6; 95% CI, 1.5–1.7). Cumulative 1-year rates of stroke ranged from 0.9% in those with subdural hemorrhage and a CHA2DS2-VASc score of 0, to 33.3% in those with intracerebral hemorrhage and a CHA2DS2-VASc score of 9.Conclusions
In a large, heterogeneous cohort, patients with atrial fibrillation faced a substantially heightened risk of ischemic stroke after intracranial hemorrhage. The risk was most marked in those with intracerebral hemorrhage and high CHA2DS2-VASc scores. 相似文献36.
Tasha M. Santiago-Rodriguez Gino Fornaciari Stefania Luciani Scot E. Dowd Gary A. Toranzos Isolina Marota Raul J. Cano 《PloS one》2015,10(9)
The process of natural mummification is a rare and unique process from which little is known about the resulting microbial community structure. In the present study, we characterized the microbiome of paleofeces, and ascending, transverse and descending colon of an 11th century A.D. pre-Columbian Andean mummy by 16S rRNA gene high-throughput sequencing and metagenomics. Firmicutes were the most abundant bacterial group, with Clostridium spp. comprising up to 96.2% of the mummified gut, while Turicibacter spp. represented 89.2% of the bacteria identified in the paleofeces. Microbiome profile of the paleofeces was unique when compared to previously characterized coprolites that did not undergo natural mummification. We identified DNA sequences homologous to Clostridium botulinum, Trypanosoma cruzi and human papillomaviruses (HPVs). Unexpectedly, putative antibiotic-resistance genes including beta-lactamases, penicillin-binding proteins, resistance to fosfomycin, chloramphenicol, aminoglycosides, macrolides, sulfa, quinolones, tetracycline and vancomycin, and multi-drug transporters, were also identified. The presence of putative antibiotic-resistance genes suggests that resistance may not necessarily be associated with a selective pressure of antibiotics or contact with European cultures. Identification of pathogens and antibiotic-resistance genes in ancient human specimens will aid in the understanding of the evolution of pathogens as a way to treat and prevent diseases caused by bacteria, microbial eukaryotes and viruses. 相似文献
37.
Haifeng Tang Yan Yan Zhe Feng Reynalda K. de Jesus Lihu Yang Dorothy A. Levorse Karen A. Owens Taro E. Akiyama Raynald Bergeron Gino A. Castriota Thomas W. Doebber Kenneth P. Ellsworth Michael E. Lassman Cai Li Margaret S. Wu Bei B. Zhang Kevin T. Chapman Sander G. Mills Joel P. Berger Alexander Pasternak 《Bioorganic & medicinal chemistry letters》2010,20(20):6088-6092
A new series of thiazole-substituted 1,1,1,3,3,3-hexafluoro-2-propanols were prepared and evaluated as malonyl-CoA decarboxylase (MCD) inhibitors. Key analogs caused dose-dependent decreases in food intake and body weight in obese mice. Acute treatment with these compounds also led to a drop in elevated blood glucose in a murine model of type II diabetes. 相似文献
38.
39.
Mechanical stimulation of tissue engineered tendon constructs: effect of scaffold materials 总被引:1,自引:0,他引:1
Nirmalanandhan VS Dressler MR Shearn JT Juncosa-Melvin N Rao M Gooch C Bradica G Butler DL 《Journal of biomechanical engineering》2007,129(6):919-923
Our group has shown that numerous factors can influence how tissue engineered tendon constructs respond to in vitro mechanical stimulation. Although one study showed that stimulating mesenchymal stem cell (MSC)-collagen sponge constructs significantly increased construct linear stiffness and repair biomechanics, a second study showed no such effect when a collagen gel replaced the sponge. While these results suggest that scaffold material impacts the response of MSCs to mechanical stimulation, a well-designed intra-animal study was needed to directly compare the effects of type-I collagen gel versus type-I collagen sponge in regulating MSC response to a mechanical stimulus. Eight constructs from each cell line (n=8 cell lines) were created in specially designed silicone dishes. Four constructs were created by seeding MSCs on a type-I bovine collagen sponge, and the other four were formed by seeding MSCs in a purified bovine collagen gel. In each dish, two cell-sponge and two cell-gel constructs from each line were then mechanically stimulated once every 5 min to a peak strain of 2.4%, for 8 h/day for 2 weeks. The other dish remained in an incubator without stimulation for 2 weeks. After 14 days, all constructs were failed to determine mechanical properties. Mechanical stimulation significantly improved the linear stiffness (0.048+/-0.009 versus 0.015+/-0.004; mean+/-SEM (standard error of the mean ) N/mm) and linear modulus (0.016+/-0.004 versus 0.005+/-0.001; mean+/-SEM MPa) of cell-sponge constructs. However, the same stimulus produced no such improvement in cell-gel construct properties. These results confirm that collagen sponge rather than collagen gel facilitates how cells respond to a mechanical stimulus and may be the scaffold of choice in mechanical stimulation studies to produce functional tissue engineered structures. 相似文献
40.
Gelmi ML Caputo F Clerici F Pellegrino S Giannaccini G Betti L Fabbrini L Schmid L Palego L Lucacchini A 《Bioorganic & medicinal chemistry》2007,15(24):7581-7589
Enantiopure constrained 1-aminocyclopentane-1,2,4-tricarboxylic acids containing the glutamic acid skeleton were prepared as two diastereomers characterized by having the carboxylic groups in position two and four cis-oriented to each other and trans with respect to 1-carboxylic group and all cis-oriented carboxylic groups, respectively. A biochemical screening of activity of the above amino acids was investigated on glutamate and 5-HT receptors to find a possible metabotropic agonist, acting on the serotoninergic system. 相似文献