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41.
Mammalian palatogenesis is a highly regulated morphogenetic process during which the embryonic primary and secondary palatal shelves develop as outgrowths from the medial nasal and maxillary prominences, respectively, remodel and fuse to form the intact roof of the oral cavity. The complexity of control of palatogenesis is reflected by the common occurrence of cleft palate in humans. Although the embryology of the palate has long been studied, the past decade has brought substantial new knowledge of the genetic control of secondary palate development. Here, we review major advances in the understanding of the morphogenetic and molecular mechanisms controlling palatal shelf growth, elevation, adhesion and fusion, and palatal bone formation. 相似文献
42.
Identifying the reproductive consequences of insect migration is critical to understanding its ecological and evolutionary significance. However, many empirical studies are seemingly contradictory, making recognition of unifying themes elusive and controversial. The beet webworm, Loxostege sticticalis L. is a long-range migratory pest of many crops in the northern temperate zone from 36 °N to 55 °N, with larval populations often exploding in regions receiving immigrants. In laboratory experiments, we examined (i) the reproductive costs of migratory flight by tethered flight, and (ii) the reproductive traits contributing to larval outbreaks of immigrant populations. Our results suggest that the beet webworm does not initiate migratory flight until the 2nd or 3rd night after emergence. Preoviposition period, lifetime fecundity, mating capacity, and egg hatch rate for adults that experienced prolonged flight after the 2nd night did not differ significantly from unflown moths, suggesting these traits are irrelevant to the severity of beet webworm outbreaks after migration. However, the period of first oviposition, a novel parameter developed in this paper measuring synchrony of first egg-laying by cohorts of post-migratory females, for moths flown on d 3 and 5 of adulthood was shorter than that of unflown moths, indicating a tightened time-window for onset of oviposition after migration. The resulting synchrony of egg-laying will serve to increase egg and subsequent larval densities. A dense population offers potential selective advantages to the individual larvae comprising it, whereas the effect from the human standpoint is intensification of damage by an outbreak population. The strategy of synchronized oviposition may be common in other migratory insect pests, such as locust and armyworm species, and warrants further study. 相似文献
43.
Juan Li Tianyi Krupka Jinpeng Yao Ronghui Wang Lin Jiang Yang Zhou Guoqing Zuo Zhibiao Wang Lili Dai Jianli Ren Yuanyi Zheng Dong Wang 《PloS one》2015,10(2)
BackgroundHIFU has been shown to be a more suitable alternative for the treatment of primary solid tumors and metastatic diseases than other focal heat ablation techniques due to its noninvasive and extracorporeal nature. However, similar to other focal heat ablation techniques, HIFU is still in need of refinements due to tumor recurrence.MethodsIn this work, we investigated the effectiveness of an adjunct treatment regimen using doxorubicin (DOX)-loaded, injectable, in situ-forming, and phase-inverting PLGA as the second line of defense after HIFU ablation to destroy detrimental residual tumors and to prevent tumor recurrence. All of the statistical analyses were performed using the Statistical Package for the Social Sciences 18.0(SPSS, Inc., Chicago, IL, USA), and p< 0.05 was considered statistically significant. All of the results are presented as the means ± STDEV (standard deviation). For multiple comparisons, ANOVA (differences in tumor volumes, growth rates, apoptosis, proliferation indexes, and Bcl-2 and Bax protein levels) was used when the data were normally distributed with homogenous variance, and rank sum tests were used otherwise. Once significant differences were detected, Student-t tests were used for comparisons between two groups.ResultsOur results revealed that DOX diffused beyond the ablated tissue regions and entered tumor cells that were not affected by the HIFU ablation. Our results also show that HIFU in concert with DOX-loaded PLGA led to a significantly higher rate of tumor cell apoptosis and a lower rate of tumor cell proliferation in the areas beyond the HIFU-ablated tissues and consequently caused significant tumor volume shrinkage (tumor volumes:0.26±0.1,1.09±0.76, and 1.42±0.9cm3 for treatment, sham, and no treatment control, respectively).ConclusionsFrom these results, we concluded that the intralesional injection of DOX-loaded PLGA after HIFU ablation is significantly more effective than HIFU alone for the treatment of solid tumors. 相似文献
44.
Objective : To determine the relative validity of specific bioelectrical impedance analysis (BIA) prediction equations and BMI as predictors of physiologically relevant general adiposity. Research Methods and Procedures : Subjects were >12, 000 men and women from the Third National Health and Nutrition Examination Survey population. We examined the correlations between BMI and percentage body fat based on 51 different predictive equations, blood pressure, and blood levels of glucose, high‐density lipoprotein cholesterol, and triglycerides, which are known to reflect adiposity, while controlling for other determinants of these physiological measures. Results : BMI consistently had one of the highest correlations across biological markers, and no BIA‐based measure was superior. Percent body fat estimated from BIA was minimally predictive of the physiological markers independent of BMI. Discussion : These results suggest that BIA is not superior to BMI as a predictor of overall adiposity in a general population. 相似文献
45.
c-Myc and Sp1 contribute to proviral latency by recruiting histone deacetylase 1 to the human immunodeficiency virus type 1 promoter 总被引:1,自引:1,他引:1 下载免费PDF全文
Histone deacetylase (HDAC) inhibitors such as valproic acid (VPA) induce the expression of quiescent proviral human immunodeficiency virus type 1 (HIV-1) and may deplete proviral infection in vivo. To uncover novel molecular mechanisms that maintain HIV latency, we sought cellular mRNAs whose expression was diminished in resting CD4(+) T cells of HIV-1-infected patients exposed to VPA. c-Myc was prominent among genes markedly downregulated upon exposure to VPA. c-Myc expression repressed HIV-1 expression in chronically infected cell lines. Chromatin immunoprecipitation (ChIP) assays revealed that c-Myc and HDAC1 are coordinately resident at the HIV-1 long terminal repeat (LTR) promoter and absent from the promoter after VPA treatment in concert with histone acetylation, RNA polymerase II recruitment, and LTR expression. Sequential ChIP assays demonstrated that c-Myc, Sp1, and HDAC1 coexist in the same DNA-protein complex at the HIV promoter. Short hairpin RNA inhibition of c-Myc reduces both c-Myc and HDAC1 occupancy, blocks c-Myc repression of Tat activation, and increases LTR expression. These results expand the understanding of mechanisms that recruit HDAC and maintain the latency of HIV-1, suggesting novel therapeutic approaches against latent proviral HIV infection. 相似文献
46.
The lesion of nucleus robustus archistriatalis (RA) has no effect on normal short calls in the bramble finch, but affects
significantly the temporal and acoustic features of learned long calls. It causes the principal frequency of basic sound in
monotone long calls to increase 500 cents, and to lose two upper partials. The lesion of RA not only results in the increased
sound length of loud-sound and shortened coda of variable-tone long calls by 13.4%–22.1% and 21.2%–24.2% on average, respectively,
but also makes the frequency rising coefficient (FRC) of even order partial tone in loud-sound drop 18.5%–25.8% on an average,
and the step-up rate decrease 22.7% –24.0% on an average with the increase of frequencies. These results show that the control
of temporal and frequency features of learned calls by RA matches to each other. Moreover, the lesion of bilateral RA can
confuse the vocal pattern, and the produced long call has the character of both the mono- and variable-tone long calls. The
prelude shows rising frequency, and the loud sound is monotone sound. 相似文献
47.
Three spoils from Bold Moss Tip, St. Helens, and one from Neston, England were collected for experiment to find the problems and solutions to reclaim the coal-mine lands of Bold Moss Tip, from seeds and tillers of Agrostis stolonifera, A. capillaris and Hocus lanatus. Low pH (3.0 to 6.8), deficient in nutrient, especially N (0. 24 to 0. 28 ppm), P(0. 016 to 6.1 ppm). and excess of Mg(>1000ppm), Na(84 to 325ppm), and Fe (>20 000ppm)were found in the spoils of Bold Moss Tip, which was supposed to be the most difficult problems of restoration. Tillers of A. stolonifera and A. capillaris could not be planted directly to the bare spoils of Bold Moss Tip, but those of vegetated spoils (Site 2 and Site 3) could support the growth of tillers. The pH value was found to be the key factor to control seed germinations of the three species, below pH 3, there were no germination. A. stolonifera and A. capillaris germinated with the highest rates (97% and 96%) at pH 5 and pH7(p<0. 01)respectively. The application of lime stone could increase spoil pH significantly (p<0. 001), from 2.2 to 7. 3, when 40 t·ha-1 lime stone was added. Lime stone had the best effect to the four spoils. Lime stone +NP significantly increased the yield of dry matters of Site 2 (p<0. 001); The highest yield, 735.6 g · m-1, was gained from the treatment of spoils of Neston with lime stone + N; Lime could also increase the yield of Site 1 from 0 to 125. l g·m-1(p<0. 05). Gypsum had some effect to spoils of Site 2 and Neston, compared with the bland treatment, but did no influence to the spoils of Site 1. Washing had minimum effect toward the spoils of Site 2, and showed no effect to Site 1 and Neston; Throughout the 8-weed% experiment there was little change in the pH of Site 1, even though the spoils were washed everyday. Fertilisers alone had no effect to the bare spoils of Bold Moss Tip, and Neston, but they could enhance the growth of seedling of Site 2, however together with lime stone, the role of fertilisers were significant (p<0. 001). Both nitrogen and phosphorus were essential to the spoils of Bold Moss Tip . Without top-soils, the bare of Bold Moss Tip can be revegetated only by application of lime stone, but better effect coult be obtained by addition of nitrogen and phosphorus. The rates of 20 to 60 t·ha-1, 75 kg N ha-1 and 50 kg P ha-1 of lime stone, nitrogen, phosphorus respectively, are suggested for application. 相似文献
48.
Inflammation may play a major role in the pathogenesis of preeclampsia (PE). In this meta-analysis, we determined whether maternal polymorphisms and serum concentrations of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and interleukin-10 (IL-10) were associated with PE. All studies investigating the associations between PE and maternal polymorphisms of TNF-α-308G/A, IL-6-174G/C, and IL-10-1082A/G or serum concentrations of TNF-α, IL-6, and IL-10 were reviewed. We found that neither maternal TNF-α-308G/A (p=0.86, odds ratio [OR]=0.98, 95% confidence interval [CI], 0.76-1.25), IL-6 174G/C (p=0.14, OR=1.23, 95% CI, 0.93-1.61), nor IL-10-1082A/G (p=0.72, OR=1.07, 95% CI, 0.75-1.52) were associated with PE. On the other hand, maternal TNF-α (p<0.00001, weighted mean difference [WMD]=19.63 pg/ml, 95% CI, 18.54-20.72 pg/ml), IL-6 (p<0.00001, WMD=6.58 pg/ml, 95% CI, 5.49-7.67 pg/ml), and IL-10 (p=0.0005, WMD=19.30 pg/ml, 95% CI, 8.42-30.17 pg/ml) concentrations were significantly higher in PE patients versus controls. Our findings strengthen the clinical evidence that PE is accompanied by exaggerated inflammatory responses, but do not support TNF-α-308G/A, IL-6-174G/C, and IL-10-1082A/G as candidate susceptibility loci in PE. 相似文献
49.
Diao Y Guo X Li Y Sun K Lu L Jiang L Fu X Zhu H Sun H Wang H Wu Z 《Cell Stem Cell》2012,11(2):231-241
In mouse skeletal muscles, Pax7 uniquely marks muscle satellite cells and plays some important yet unknown functions at the perinatal stage. To elucidate its in vivo functions, we initiated a yeast two-hybrid screening to look for Pax7-interacting proteins and identified a previously uncharacterized Pax7- and Pax3-binding protein (Pax3/7BP). Pax3/7BP is a ubiquitously expressed nuclear protein, enriched in Pax7+ muscle precursor cells (MPCs), and serves as an indispensable adaptor for Pax7 to recruit the histone 3 lysine 4 (H3K4) methyltransferase (HMT) complex by bridging Pax7 and Wdr5. Knockdown of Pax3/7BP abolished the Pax3/7-associated H3K4 HMT activity and inhibited the proliferation of Pax7+ MPCs from young mice both in culture and in vivo. Id3 and Cdc20 were direct target genes of Pax7 and Pax3/7BP involved in the proliferation of Pax7+ MPCs. Collectively, our work establishes Pax3/7BP as an essential adaptor linking Pax3/7 with the H3K4 HMT to regulate the proliferation of MPCs. 相似文献
50.
Identification of a stable quantitative trait locus for percentage grains with white chalkiness in rice (Oryza sativa) 总被引:1,自引:0,他引:1
Guo T Liu X Wan X Weng J Liu S Liu X Chen M Li J Su N Wu F Cheng Z Guo X Lei C Wang J Jiang L Wan J 《植物学报(英文版)》2011,53(8):598-607
High chalkiness is a major problem in many rice-producing areas of the world, especially in hybrid rice (Oryza sativa L.) in China. We previously showed a major quantitative trait locus for the percentage of grains with white chalkiness (QTLqPGWC-8) in the interval G1149-R727 on chromosome 8 using a chromosome segment substitution line (CSSL). Here, we selected the line-CSSL50 harboring the QTLqPGWC-8 allele from the CSSLs derived from a cross between Asominori (as a recurrent parent) and IR24 (as a donor parent), which had higher percentage chalkiness, markedly different from that of Asominori. There were also significant differences in starch granules, appearance of amylose content (AAC) and milling qualities between Asominori and CSSL50, but not in grain size or thousand grain weight (TGW). The BC(4) F(2) and BC(4) F(3) populations from a cross between CSSL50 and Asominori were used for fine mapping of qPGWC-8. We narrowed down the location of this QTL to a 142 kb region between Indel markers 8G-7 and 8G-9. QTLqPGWC-8 accounted for 50.9% of the difference in PGWC between the parents. The markers tightly linked to qPGWC-8 should facilitate cloning of the gene underlying this QTL and will be of value for marker-assisted selection in breeding rice varieties with better grain quality. 相似文献