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21.
Vegetable crops in the southeastern United States are commonly grown on plastic mulch with two crop cycles produced on a single mulch application. Field trials were conducted in 2013 and 2014 in two locations to evaluate the efficacy of fluensulfone for controlling Meloidogyne spp. when applied through drip irrigation to cucumber in a tomato–cucumber double-cropping system. In the spring tomato crop, 1,3-dichloropropene (1,3-D), fluensulfone, and a resistant cultivar significantly decreased root galling by 91%, 73%, and 97%, respectively, compared to the untreated control. Tomato plots from the spring were divided into split plots for the fall where the main plots were the spring treatment and the subplots were cucumber either treated with fluensulfone (3.0 kg a.i./ha. via drip irrigation) or left untreated. The fall application of fluensulfone improved cucumber vigor and reduced gall ratings compared to untreated subplots. Fluensulfone reduced damage from root-knot nematodes when applied to the first crop as well as provided additional protection to the second crop when it was applied through a drip system.  相似文献   
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Recent studies have implicated the dying cell as a potential reservoir of modified autoantigens that might initiate and drive systemic autoimmunity in susceptible hosts. A number of subunits of the exosome, a complex of 3'→5' exoribonucleases that functions in a variety of cellular processes, are recognized by the so-called anti-PM/Scl autoantibodies, found predominantly in patients suffering from an overlap syndrome of myositis and scleroderma. Here we show that one of these subunits, PM/Scl-75, is cleaved during apoptosis. PM/Scl-75 cleavage is inhibited by several different caspase inhibitors. The analysis of PM/Scl-75 cleavage by recombinant caspase proteins shows that PM/Scl-75 is efficiently cleaved by caspase-1, to a smaller extent by caspase-8, and relatively inefficiently by caspase-3 and caspase-7. Cleavage of the PM/Scl-75 protein occurs in the C-terminal part of the protein at Asp369 (IILD369↓G), and at least a fraction of the resulting N-terminal fragments of PM/Scl-75 remains associated with the exosome. Finally, the implications of PM/Scl-75 cleavage for exosome function and the generation of anti-PM/Scl-75 autoantibodies are discussed.  相似文献   
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Through the use of computational modeling, a series of pyrimidinetrione-based inhibitors of MMP-13 was designed based on a lead inhibitor identified through file screening. Incorporation of a biaryl ether moiety at the C-5 position of the pyrimidinetrione ring resulted in a dramatic enhancement of MMP-13 potency. Protein crystallography revealed that this moiety binds in the S(1)(') pocket of the enzyme. Optimization of the C-4 substituent of the terminal aromatic ring led to incorporation of selectivity versus MMP-14 (MT-1 MMP). Structure activity relationships of the biaryl ether substituent are presented as is pharmacokinetic data for a compound that meets our in vitro potency and selectivity goals.  相似文献   
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In species that lack parental care and whose larvae are restricted to a given space throughout development, choice of egg-laying or reproductive sites often greatly influences fitness. Furthermore, reproductive success of individuals may be affected not only by conditions of the breeding area but also by the time when they start to breed, because intraspecific variation in the timing of breeding may result in asymmetric competition between larvae. We addressed these issues in an experimental and field study of the Japanese brown frog, Rana japonica. We tested whether the survival success of larvae decreased with an increase in the number of deposited egg masses and with a greater delay in oviposition. We found that the number of egg masses and timing of oviposition together significantly predicted larval survival per clutch. Moreover, we observed the natural oviposition of R. japonica to examine the prediction that if the density of larvae and the timing of oviposition affect survivorship of larvae, R. japonica will avoid depositing eggs in pools in which egg masses have already been deposited. We found that for small pools only, R. japonica tended to favor oviposition at unoccupied pools (those lacking egg masses and larvae) in the spawning season. For large pools, however, adults favored those already occupied by egg masses in the spawning period. The density of egg masses and tadpoles or the timing of oviposition may have less effect on spawning or the survival of tadpoles in large pools than in small pools.  相似文献   
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The extracellular glycoproteins fibrillin-1 and fibrillin-2 are major components of connective tissue microfibrils. Mutations in the fibrillin-1 and fibrillin-2 genes are responsible for the phenotypical manifestations of Marfan syndrome and congenital contractural arachnodactyly respectively, which emphasizes their essential roles in developmental processes of various tissues. Consistent with this last notion, organ culture experiments have indirectly suggested morphogenic roles for fibrillins in lung and kidney development. In order to contribute to the understanding of the roles of fibrillins in developmental and morphogenetic events, we have investigated the distribution of fibrillin-1 and fibrillin-2 in human embryonic and early fetal tissues between the 5th and the 12th gestational week, i.e. at the beginning of organogenesis. Fibrillin-1 and fibrillin-2 were localized immunohistochemically using specific monoclonal antibodies, mAb 69 and mAb 48, respectively. Both fibrillins are widely distributed in various human anlagen, from early developmental stages. In most embryonic and early fetal human organs such as skin, lung, heart, aorta, central nervous system anlage, nerves, and ganglia, fibrillin-1 and fibrillin-2 follow the same temporo-spatial pattern of distribution. However, in other organs such as kidney, liver, rib anlagen, notochord fibrillin-1 and fibrillin-2 are distributed differentially. The present paper is focused on this aspect. These results suggest different roles for fibrillin-1 and -2 in the development of these structures.  相似文献   
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The efficacy of the regular elicitation of the relaxation response in reducing surgical anxiety and pain in an ambulatory surgery setting was studied in a population of patients scheduled for the surgical removal of a skin cancer. Forty-nine patients with skin cancer were enrolled in the study immediately after being informed of the ned for surgery; 21 of these patients elicited the relaxation response 20 minutes per day until the day of surgery, 21 read for 20 minutes per day, and 7 were noncompliant and were excluded from the study. Contrary to expectations, neither group of patients showed any increase in anxiety immediately before or after surgery on either psychological or physiological measures. Thus, there were no differences between the two groups on any of the psychological or physiological measures of anxiety, nor were there any differences in pain perception. There were statistically significant subjective differences; the experimental patients stated that the relaxation-response technique had reduced their anxiety several days before surgery and reportedly experienced their highest levels of anxiety prior to entering the study, while the controls experienced their highest levels of anxiety during and after surgery. This suggests that (1) minor outpatient surgery does not lead to detectable increased anxiety levels on the day of surgery and (2) regular elicitation of the relaxation response can alter subjective reports of distress associated with surgery.  相似文献   
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