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191.
In Arabidopsis , NPR1 ( AtNPR1 ) regulates salicylic acid (SA)-mediated activation of PR genes at the onset of systemic acquired resistance. AtNPR1 also modulates SA-induced suppression of jasmonic acid-responsive gene expression, and npr1 mutants manifest enhanced herbivore resistance. We have raised stable transgenic tobacco lines, expressing AtNPR1 constitutively, which showed elevated expression of PR1 and PR2 genes upon SA treatment. Herbivore bioassays with a generalist polyphagous pest, Spodoptera litura , revealed that the transgenic lines exhibited enhanced resistance compared to the wild-type plants, particularly with respect to younger larval populations. Insect-mediated injury induced several protease inhibitors (PIs), more significantly a 40-kDa serine PI in all the tobacco lines, but the induction was higher in the transgenic plants. We show in this communication that heterologous expression of AtNPR1 provides enhanced resistance to early larval populations of the herbivore, Spodoptera in transgenic tobacco plants.  相似文献   
192.
Kinesin-13, an end depolymerizer of cytoplasmic and spindle microtubules, also affects the length of cilia. However, in different models, depletion of kinesin-13 either lengthens or shortens cilia, and therefore the exact function of kinesin-13 in cilia remains unclear. We generated null mutations of all kinesin-13 paralogues in the ciliate Tetrahymena. One of the paralogues, Kin13Ap, localizes to the nuclei and is essential for nuclear divisions. The remaining two paralogues, Kin13Bp and Kin13Cp, localize to the cell body and inside assembling cilia. Loss of both Kin13Bp and Kin13Cp resulted in slow cell multiplication and motility, overgrowth of cell body microtubules, shortening of cilia, and synthetic lethality with either paclitaxel or a deletion of MEC-17/ATAT1, the α-tubulin acetyltransferase. The mutant cilia assembled slowly and contained abnormal tubulin, characterized by altered posttranslational modifications and hypersensitivity to paclitaxel. The mutant cilia beat slowly and axonemes showed reduced velocity of microtubule sliding. Thus kinesin-13 positively regulates the axoneme length, influences the properties of ciliary tubulin, and likely indirectly, through its effects on the axonemal microtubules, affects the ciliary dynein-dependent motility.  相似文献   
193.
Human Vγ9Vδ2 T cells are well known for their rapid and potent response to infection and tumorigenesis when in the presence of endogenous or exogenous phosphoisoprenoids. However, the molecular mechanisms behind the activation of this γδ T cell population remains unclear. Evidence pointing to a role for the CD277/butyrophilin-3 (BTN3A) molecules in this response led us to investigate the structures of these molecules and their modifications upon binding to an agonist antibody (20.1) that mimics phosphoisoprenoid-mediated Vγ9Vδ2 activation and an antagonist antibody (103.2) that inhibits this reactivity. We find that the three BTN3A isoforms: BTN3A1, BTN3A2, and BTN3A3, have high structural homology to the B7 superfamily of proteins and exist as V-shaped homodimers in solution, associating through the membrane proximal C-type Ig domain. The 20.1 and 103.2 antibodies bind to separate epitopes on the BTN3A Ig-V domain with high affinity but likely with different valencies based on their binding orientation. These structures directly complement functional studies of this system that demonstrate that BTN3A1 is necessary for Vγ9Vδ2 activation and begin to unravel the extracellular events that occur during stimulation through the Vγ9Vδ2 T cell receptor.  相似文献   
194.
Acinetobacter sp. evolved 14CO2 from 14C-(ring)DHP lignin and 14C-teakwood lignin. Veratrylglycerol-beta-guaiacyl ether, a lignin model compound with beta-o-4 linkage was cleaved by Acinetobacter sp. Veratrylglycerol-beta-guaiacyl ether into 2(o-methoxyphenoxy) ethanol and veratrylalcohol 2(o-methoxyphenoxy) ethanol was degraded to guaiacol and then to catechol whereas veratrylalcohol was converted to veratraldehyde, veratric acid, vanillic acid, protocatechuic acid and catechol. Both catechol 1,2-dioxygenase and protocatechuate 3,4-dioxygenase were detected in veratrylglycerol-beta-guaiacyl ether grown cultures.  相似文献   
195.
Following the infection of insect ovarian cells (Sf9) with recombinant bearing the cDNA coding for the rat muscarinic acetylcholine (ACh) receptor subtype m3, ionic flux across the membrane in response to the application of ACh was examined electrophysiologically. We show that ACh activates potassium currents. The response is abolished when cells are treated with pertussis toxin. No ACh-induced currents are observed from uninfected cells or cells infected with virus which do not contain the cDNA coding for ACh receptors in its genome. The characteristics of single channel currents show time-dependent changes following the application of ACh. Initially, ACh activates brief channel currents with a conductance of about 5 pS. The conductance level of channels gradually increases in steps to 10 pS and then to 20 pS and 40 pS. At the same time, channel open probability also increases. Thereafter, additional channels appear, opening and closing independently of, or at times in synchrony with, the original channel.  相似文献   
196.
Exopolysaccharide produced by a unique avirulent Bacillus anthracis strain PFAB2 of hot spring origin has been characterized and its functional properties are investigated which is a first report. Maximum yield of EPS is 7.66 g/l with 2% glucose and 1% peptone as optimum carbon and nitrogen source respectively. The EPS is found to be a homopolymer consisting of only glucose as principle monosaccharide component. Through 1H NMR study, different dextran-like proton peaks are observed. Molecular weight of the EPS resembles low molecular weight bacterial origin polysaccharides. Melting transition of the EPS has started after 276 °C which indicates good thermal stability. The EPS also shows potent antioxidant activity in terms of DPPH and ABTS mediated free radical scavenging property compared to standard ascorbic acid. Emulsifying property of the EPS is also observed and has shown good emulsification of vegetable oils. The polysaccharide forms a thermo resistant gel during the heating phase, with G′ higher than G″ indicating excellent shear-thinning behaviour and viscoelastic nature of the EPS.  相似文献   
197.

Background

There is no convincing data on the trends of hospitalizations, mortality, cost, and demographic variations associated with inpatient admissions for gastric cancer in the USA. The aim of this study was to use a national database of US hospitals to evaluate the trends associated with gastric cancer.

Methods

We analyzed the National Inpatient Sample (NIS) database for all patients in whom gastric cancer (ICD-9 code: 151.0, 151.1, 151.2, 151.3, 151.4, 151.5, 151.6, 151.8, 151.9) was the principal discharge diagnosis during the period, 2003–2014. The NIS is the largest publicly available all-payer inpatient care database in the US. It contains data from approximately eight million hospital stays each year. The statistical significance of the difference in the number of hospital discharges, length of stay, and hospital costs over the study period was determined by regression analysis.

Results

In 2003, there were 23,921 admissions with a principal discharge diagnosis of gastric cancer as compared to 21,540 in 2014 (P?<?0.01). The mean length of stay for gastric cancer decreased by 17% between 2003 and 2014 from 10.9?days to 8.95?days (P?<?0.01). However, during this period, the mean hospital charges increased significantly by 21% from $ 75,341 per patient in 2003 to $ 91,385 per patient in 2014 (P?<?0.001). There was a more significant reduction in mortality over a period of 11?years from 2428 (10.15%) in 2003 to 1345 (6.24%) in 2014 (P?<?0.01). The aggregate charges (i.e., “national bill”) for gastric cancer increased significantly from 1.79 bn $ to 1. 96 bn $ (P?<?0.001), despite decrease in hospitalization (inflation adjusted).

Conclusion

Although the number of inpatient admissions for gastric cancer have decreased over the past decade, the healthcare burden and cost related to it has increased significantly. Inpatient mortality is decreasing which is consistent with overall decrease in gastric cancer-related deaths. Cost increase associated with gastric cancer contributed significantly to the national healthcare bill.
  相似文献   
198.
Protein deficiency was produced by feeding synthetic 8%-protein diet. Lithium carbonate at the dose level of 1.1g/kg diet was administered to normal and protein-deficient rats for a period of one mo. A significant inhibition in the levels of cytochrome (cyt) P450, cyt b5, glutathione (GSH), glutathione S-transferase (GST) and glutathione peroxidase (GPx), but an increase in γ-glutamyl transpeptidase (γ-GT), was observed in low-protein LP-fed rats. Lithium treatment to normal rats caused no significant change in the activities of cyt P450, cyt b5, GST, and GSH levels, whereas there was elevation in the activities of γ-GT and GPx and suppression in glutathione reductase (GRd) activity. Lithium administration to LP-fed rats resulted in significant increases in the hepatic γ-GT and GPx activities.  相似文献   
199.
A new bufonid amphibian, belonging to a new monotypic genus, is described from the Andaman Islands, in the Bay of Bengal, Republic of India, based on unique external morphological and skeletal characters which are compared with those of known Oriental and other relevant bufonid genera. Blythophryne gen. n. is distinguished from other bufonid genera by its small adult size (mean SVL 24.02 mm), the presence of six presacral vertebrae, an absence of coccygeal expansions, presence of an elongated pair of parotoid glands, expanded discs at digit tips and phytotelmonous tadpoles that lack oral denticles. The taxonomic and phylogenetic position of the new taxon (that we named as Blythophryne beryet gen. et sp. n.) was ascertained by comparing its 12S and 16S partial genes with those of Oriental and other relevant bufonid lineages. Resulting molecular phylogeny supports the erection of a novel monotypic genus for this lineage from the Andaman Islands of India.  相似文献   
200.
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