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Paxillin facilitates timely neurite initiation on soft-substrate environments by interacting with the endocytic machinery.
Neurite initiation is the first step in neuronal development and occurs spontaneously in soft tissue environments. Although the mechanisms regulating the morphology of migratory cells on rigid substrates in cell culture are widely known, how soft environments modulate neurite initiation remains elusive. Using hydrogel cultures, pharmacologic inhibition, and genetic approaches, we reveal that paxillin-linked endocytosis and adhesion are components of a bistable switch controlling neurite initiation in a substrate modulus-dependent manner. On soft substrates, most paxillin binds to endocytic factors and facilitates vesicle invagination, elevating neuritogenic Rac1 activity and expression of genes encoding the endocytic machinery. By contrast, on rigid substrates, cells develop extensive adhesions, increase RhoA activity and sequester paxillin from the endocytic machinery, thereby delaying neurite initiation. Our results highlight paxillin as a core molecule in substrate modulus-controlled morphogenesis and define a mechanism whereby neuronal cells respond to environments exhibiting varying mechanical properties
Spatial heterogeneity of tectonic stress and friction in the crust: new evidence from earthquake focal mechanisms in Taiwan
We performed inversions of earthquake focal mechanisms in central Taiwan to investigate the heterogeneity of the stress field and fault strength, and temporal variations of stress parameters, friction and pore pressure associated with the 1999 Chi-Chi earthquake. We divided the focal mechanism data into two groups: before and after the Chi-Chi earthquake, and analysed them separately. With the assumption of a uniform stress field, the friction coefficient is mostly within a range of 0.2–0.4 in central Taiwan, which is lower than the commonly quoted laboratory result, 0.6–0.85. The low friction coefficient is also inferred by the rotation of principal stress axes after the Chi-Chi earthquake. By contrast, if we assume that the friction is constant and failures occur on optimally oriented planes, we find that the resulting stress orientations must be spatially variable. However, a large dispersion of stress orientations is not seen in borehole breakouts and fault slip data, implying a constant friction model might be ruled out. Our analysis suggests that either the distribution of the coefficient of friction or pore pressure changed during the 1999 Chi-Chi earthquake. We infer that the pore pressure probably rose in the Chi-Chi rupture area and northern Longitudinal Valley and dropped in the areas south of the coseismic rupture area after the main shock
Comparison of laparoscopic versus open surgery in a three-stage operation for obstructive left-sided colorectal cancer
AbstractBackgroundTreatment for obstructive left-sided colorectal cancer (OLCC) typically consists of a three-staged procedure. During the first stage, the obstruction is managed with diversion colostomy. Traditionally in the second stage, we perform open resection for the primary tumor. In this study, we evaluated the feasibility of laparoscopic resection of OLCC with diversion colostomy in terms of operative results and short-term outcomes.MethodsA total of 20 patients underwent laparoscopic resection for OLCC (study group), 48 patients underwent open resection for OLCC (control group 1), and 53 patients underwent laparoscopic resection for non-OLCC (control group 2). Afterwards, results from the procedures were obtained and clinical data were analyzed.ResultsThe operative time was significantly longer in the study group than in the control group 1 (153 minutes vs. 126 minutes, p = 0.041), and the length of hospitalization was shorter in the study group than in the control group 1 (5.3 days vs. 7.6 days, p = 0.032). Regarding the operative results and short-term outcomes, there were no significant differences between the study group and control group 2. Colostomy retraction was a specific morbidity which occurred in two patients of the study group.ConclusionLaparoscopic resection of OLCC with diversion colostomy is feasible. Abdominal cavity adhesion is only limited. We strongly recommend that laparoscopic resection should be performed at least 2 weeks after diversion colostomy, and the plastic rod should be left in place during the pneumoperitoneum to reduce the risk of colostomy retraction
Lightest Higgs boson decays in the from supersymmetric standard model
We study the lightest Higgs boson decays in the framework
of the from supersymmetric standard model (SSM), where
is a vector meson . Compared to the minimal
supersymmetric standard model (MSSM), the SSM introduces three
right-handed neutrino superfields, which lead to the mixing of the Higgs
doublets with the sneutrinos. The mixing affects the lightest Higgs boson mass
and the Higgs couplings. Compared to the standard model, the SSM can
give large new physics contributions to the decay width of in
suitable parameter space, which may be detected by the HL-LHC or the other
future high energy colliders.Comment: 15 pages, 5 figures. arXiv admin note: substantial text overlap with
arXiv:2002.0437
Two variants on T2DM susceptible gene HHEX are associated with CRC risk in a Chinese population
Increasing amounts of evidence has demonstrated that T2DM (Type 2 Diabetes Mellitus) patients have increased susceptibility to CRC (colorectal cancer). As HHEX is a recognized susceptibility gene in T2DM, this work was focused on two SNPs in HHEX, rs1111875 and rs7923837, to study their association with CRC. T2DM patients without CRC (T2DM-only, n=300), T2DM with CRC (T2DM/CRC, n=135), cancer-free controls (Control, n=570), and CRC without T2DM (CRC-only, n=642) cases were enrolled. DNA samples were extracted from the peripheral blood leukocytes of the patients and sequenced by direct sequencing. The χ(2) test was used to compare categorical data. We found that in T2DM patients, rs1111875 but not the rs7923837 in HHEX gene was associated with the occurrence of CRC (p= 0.006). for rs1111875, TC/CC patients had an increased risk of CRC (p=0.019, OR=1.592, 95%CI=1.046-2.423). Moreover, our results also indicated that the two variants of HEEX gene could be risk factors for CRC in general population, independent on T2DM (p< 0.001 for rs1111875, p=0.001 for rs7923837). For rs1111875, increased risk of CRC was observed in TC or TC/CC than CC individuals (p<0.001, OR= 1.780, 95%CI= 1.385-2.287; p<0.001, OR= 1.695, 95%CI= 1.335-2.152). For rs7923837, increased CRC risk was observed in AG, GG, and AG/GG than AA individuals (p< 0.001, OR= 1.520, 95%CI= 1.200-1.924; p=0.036, OR= 1.739, 95%CI= 0.989-3.058; p< 0.001, OR= 1.540, 95%CI= 1.225-1.936). This finding highlights the potentially functional alteration with HHEX rs1111875 and rs7923837 polymorphisms may increase CRC susceptibility. Risk effects and the functional impact of these polymorphisms need further validation
Comparison of gene expression profiles in Bacillus megaterium treated tobacco leaves using microarray
The MP agent, prepared from Bacillus megaterium isolated from the soil near tobacco fields, can improve metabolic products, and hence the aroma, of tobacco (Nicotiana tabacum) leaf. To explore genes regulating metabolic responses in tobacco leaf, we used microarrays to analyze differentially expressed genes in tobacco leaves subjected to various treatments. The expressed genes were classified into six groups based on their expression profile. In total, 753 genes were significantly differentially expressed between microorganism-treated and water-treated samples. Gene ontology (GO) analyses showed that most of these genes were involved in metabolic and cellular processes. Some upregulated genes were related to the plant defense response, such as NtMMP1 and NtACRE231. Some genes were involved in metabolism responses, such as NtDXS. Semi-quantitative reverse transcriptase (RT)-PCR analysis of NtMMP1 and quantitative RT-PCR analysis of NtDXS showed that their expression levels increased after MP agent treatment, confirming the microarray results. We evaluated NtMMP1 and NtDXS in terms of their associations with Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Phylogenetic analyses of NtMMP1, NtACRE231, and NtDXS revealed their relationships with homologs in other species. These microarray data increase our understanding of the mechanisms by which MP agent induces a metabolic response in tobacco leavesKey words: Nicotiana tabacum, Microarray, MP agent, plant defense response, aroma
The prevalence of ocular diseases in primary and junior high school students on Orchid Island
AbstractObjectiveTo assess the prevalence of refractive error and ocular diseases in primary and junior high school students on Orchid Island.Materials and MethodsThis is a cross-sectional study of all students in the primary and junior high schools on Orchid Island conducted within 1 week in 2008. Each student received a visual acuity examination without correction with the Landolt-C chart. An experienced ophthalmologist performed associated assessments through retinoscopy, slit lamp, and fundoscopy.ResultsOf the 403 student residents, 260 were primary school students (139 boys and 121 girls) and 143 were junior high school students (74 boys and 69 girls). Visual acuity in two eyes was < 0.1, in 14 eyes was between 0.1 and 0.3, in 34 eyes was between 0.4 and 0.7, in 225 eyes was between 0.8 and 1.0, and in 531 eyes was between 1.2 and 2.0. Myopia was found in 21 students (21/403, 5.21%; 9 primary school students and 12 junior high school students). Four students (4/403, 0.99%) had amblyopia, of whom two had anisometropia (unilateral high hyperopia), one had high astigmatism in both eyes, and the other had unilateral esotropia. Lens dislocation was found in one student (0.25%) with Marfan syndrome. Retinal vasculitis and optic atrophy were found in one student (0.25%) with systemic lupus erythematosus.ConclusionBecause it is a small, isolated island, Orchid Island still has a unique traditional culture and life style. Therefore the prevalence of myopia in primary school and junior high school students on Orchid Island is low, and 94% of all the students had uncorrected visual acuity above 0.8
Low-cell-number, single-tube amplification (STA) of total RNA revealed transcriptome changes from pluripotency to endothelium
Table S1. Summary of the sequencing results. The alignments against the GRCh38 genome assembly (Aligned Reads) were counted for exon reads (exon) and transcript reads based on GENCODE v22. Intronic counts (intron) were defined by transcript counts minus exon ones. Nontranscript reads were used to obtain tRNA counts (tRNA) based on the tRNA database of GENCODE v22. Nontranscript and non-tRNA reads were used for counts on repetitive sequences (repeats) based on RepeatMasker. Those not belonging to any category were defined as unannotated reads (unannotated). The counting of exonic features was based on the “gene_type” attribute in GENCODE v22. The percentages of mature miRNA reads were defined by reads aligned exclusively to the mature “miRNA” feature divided by reads aligned to the “miRNA_primary_transcript” feature of miRBase v21. (DOCX 42 kb
Extract from Periostracum cicadae
Periostracum cicadae is widely used for the treatment of skin diseases such as eczema, pruritus, and itching. The current study sought to evaluate the effect of P. cicadae extract on ultraviolet B (UVB) irradiation and identify the mechanisms involved. Photodamage-protective activity of P. cicadae extracts against oxidative challenge was screened using HaCaT keratinocytes. P. cicadae extracts did not affect cell viability but decreased reactive oxygen species (ROS) production. The extract attenuates the expression of interleukin-6 (IL-6), matrix metalloproteinase-2 (MMP-2), and MMP-9 in UVB-treated HaCaT cells. Also, P. cicadae abrogated UVB-induced activation of NF-κB, p53, and activator protein-1 (AP-1). The downmodulation of IL-6 by P. cicadae was inhibited by the p38 inhibitor (SB203580) or JNK inhibitor (SP600125). Moreover, the extract attenuated the expression of NF-κB and induced thrombomodulin in keratinocytes and thereby effectively downregulated inflammatory responses in the skin. The nuclear accumulation and expression of NF-E2-related factor (Nrf2) were increased by P. cicadae treatment. Furthermore, treatment with P. cicadae remarkably ameliorated the skin’s structural damage induced by irradiation. This study demonstrates that P. cicadae may protect skin cells against oxidative insult by modulating ROS concentration, IL-6, MMPs generation, antioxidant enzymes activity, and cell signaling pathways
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