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Background The PIK3CA gene mutation was found to associate with prognosis and might affect molecular targeted therapy in esophageal carcinoma (EC). The aim of this study is to compare different methods for analyzing the PIK3CA gene mutation in EC. Methods Genomic DNA was extracted from 106 surgically resected EC patient tissues. The PIK3CA mutation status (exons 9 and 20) were screened by mutant-enrich liquid chip (MELiquidchip), Sanger sequencing, and pyrosequencing. And all samples with mutations were independently reassessed using amplification refractory mutation system (ARMS) methods again. Results PIK3CA mutation rates were identified as 11.3% (12/106) by ME-Liquidchip. 10 mutations occurred in exon 9 and 2 in exon 20, including G1624A:E542K (n = 4), G1633A:E545K (n = 6) and A3140G:H1047R (n = 2). The results were further verified by ARMS methods. Among these 12 cases characterized for PIK3CA mutation, however, only 7 and 6 cases were identified by Sanger sequencing (6.6%,7/106) and pyrosequencing (5.7%,6/106), respectively. Conclusion Sanger sequencing and pyrosequencing are less sensitive and are not efficiently applicable to the detection of PIK3CA mutation in EC samples. Choosing between ME-Liquidchip and ARMS will depend on laboratory facilities and expertise. [ABSTRACT FROM AUTHOR]

PIK3CA gene mutations are found in numerous cancers but correlate differently with prognosis. Although the frequency of PIK3CA gene mutation in esophageal squamous cell carcinoma (ESCC) has been previously studied, a prognostic analysis has not been reported. Ninety-six surgically resected ESCC tissues were collected from Chinese patients and DNA was extracted. Gene mutations in PIK3CA (exons 9 and 20), EGFR (exons 18, 19, 20 and 21), KRAS (exons 2 and 3), and BRAF (exons 11 and 15) were screened using mutant-enriched liquid chip technology. PIK3CA gene mutations were identified in 12 of 96 ESCC cases (12.5%). No mutations were identified in EGFR, KRAS or BRAF genes in this study. Correlations between clinicopathological features and PIK3CA mutation status were analyzed and finally, patient survival information was used to determine the prognostic significance of PIK3CA mutation. Interestingly, the frequency of PIK3CA mutation was higher in female ESCC patients (31.3%, 5/16) than in males (8.8%, 7/80), and higher in patients with non-lymph node metastasis (19.6%, 10/51, P = .013) than in patients with lymph node metastasis (4.4%, 2/45, P = .025). Furthermore, patients with PIK3CA-mutated tumors showed a trend towards favorable overall survival (P = .085) but not disease-free survival (P = .238), suggesting that PIK3CA gene status may be a favorable predictive marker in ESCC patients. [ABSTRACT FROM AUTHOR]

Intra-abdominal fibromatosis (IAF) commonly develops in patients who had abdominal surgery. In rare instances, it occurs subsequent to gastrointestinal stromal tumor (GIST). This special situation has clinical significance in imatinib era. About 1000 patients with GIST in our institution from 1993 to 2010 were re-evaluated based on their clinical and pathological data, the treatment strategies and the follow-up information. We identified 2 patients who developed IAF after GIST resection. Patient 1 was a 54 year-old male and had 5 cm × 4.5 cm × 3.5 cm jejunal GIST excised on February 22, 1994. Three years later, an abdominal mass with 7 cm × 6 cm × 3 cm was identified. He was diagnosed as recurrent GIST from clinical point of view. After excision, the second tumor was confirmed to be IAF. Patient 2 was a 45-year-old male and had 6 cm × 4 cm × 3 cm duodenal GIST excised on August 19, 2008. One year later, a 4 cm mass was found at the original surgical site. The patient refused to take imatinib until the tumor increased to 8 cm six months later. The tumor continued to increase after 6 months’ imatinib therapy, decision of surgical resection was made by multidisciplinary team. The second tumor was confirmed to be IAF with size of 17 cm × 13 cm × 11 cm. Although IAF subsequent to GIST is very rare, it is of clinical significance in imatinib era as an influencing factor for making clinical decision. [ABSTRACT FROM AUTHOR]

Background: Tissue microarray (TMA) is a high throughput research tool, which has greatly facilitated and accelerated in situ tissue analyses. However, its productivity has been restricted due to the confined thickness of traditional donor block. Here, we introduce an improved high output TMA method that is applicable to a broader range of tissue samples. Methods: In this method, a 3.6 cm long and 2.7 cm wide recipient block with 88 square lattices (3 mm in width) was first prepared using several commercial instruments. A 2 mm wide and 6 mm long tissue rod was then prepared using a self-made blade-shaped knife from each paraffin embedded donor block of gastrointestinal stromal tumors. These rods were manually arrayed one by one into the corresponding lattices of the 60°C pre-softened recipient block with the guide of holes drilled with a steel needle. A 70-rod TMA was made to testify this method. Results: The prepared TMA had well defined array configurations, good tissue morphology and fully preserved proteins and DNA. A total of 500-1000 TMA sections could be easily obtained from a TMA block. Conclusion: This low-cost and time-saving method provides an alternative sampling tool for high output TMA. [ABSTRACT FROM AUTHOR]

Background: Trastuzumab is currently approved for the clinical treatment of breast and gastric cancer patients with HER-2 positive tumors, but not yet for the treatment of esophageal carcinoma patients, whose tumors typically show 5 ~ 35% HER-2 gene amplification and 0 ~ 56% HER-2 protein expression. This study aimed to investigate the therapeutic efficacy of Trastuzumab in patient-derived esophageal squamous cell carcinoma xenograft (PDECX) mouse models. Methods: PDECX models were established by implanting patient esophageal squamous cell carcinoma (ESCC) tissues into immunodeficient (SCID/nude) mice. HER-2 gene copy number (GCN) and protein expression were determined in xenograft tissues and corresponding patient EC samples by FISH and IHC analysis. Trastuzumab anti-tumor efficacy was evaluated within these PDECX models (n = 8 animals/group). Furthermore, hotspot mutations of EGFR, K-ras, B-raf and PIK3CA genes were screened for in the PDECX models and their corresponding patient's ESCC tissues. Similarity between the PDECX models and their corresponding patient's ESCC tissue was confirmed by histology, morphology, HER-2 GCN and mutation. Results: None of the PDECX models (or their corresponding patient's ESCC tissues) harbored HER-2 gene amplification. IHC staining showed HER-2 positivity (IHC 2+) in 2 PDECX models and negativity in 3 PDECX models. Significant tumor regression was observed in the Trastuzumab-treated EC044 HER-2 positive model (IHC 2+). A second HER-2 positive (IHC 2+) model, EC039, harbored a known PIK3CA mutation and showed strong activation of the AKT signaling pathway and was insensitive to Trastuzumab treatment, but could be resensitised using a combination of Trastuzumab and AKT inhibitor AZD5363. In summary, we established 5 PDECX mouse models and demonstrated tumor regression in response to Trastuzumab treatment in a HER-2 IHC 2+ model, but resistance in a HER-2 IHC 2+/PIK3CA mutated model. Conclusions: This study demonstrates Trastuzumab-induced tumor regressions in HER-2 positive tumors, and highlights PIK3CA mutation as a potential resistance mechanism to Trastuzumab treatment in pre-clinical patient-derived EC xenograft models. [ABSTRACT FROM AUTHOR]

This study is to examine the effect of stem architecture on biomass allocation between leaf and stem and between leaf size and number in plant twigs of woody species. We investigated leaf size, leaf number, stem length, stem diameter, and mass for 282 woody species of subtropical evergreen broad-leaved forests in southwest China. Both stem diameter and stem length were positively correlated with individual leaf mass and area but were negatively associated with leaf number per unit stem mass and leaf number per stem length. This suggests that these stem architecture traits can be a physiological mechanism underlying the leaf size versus leaf number tradeoff. The ratio of stem length to stem diameter (LDR) was negatively correlated with leaf size and leaf number per stem length, due to the difference in the strength of the effects of stem length and stem diameter on leaf size and leaf number. Similarly, both stem diameter and stem length were positively correlated with leaf mass and stem mass. LDR was negatively correlated with leaf biomass fraction (the ratio of leaf mass to twig mass), due to the difference in the strength of the effect of stem length and stem diameter on leaf mass and stem mass. This indicates that stem architecture can significantly influence biomass allocation between leaf and stem. These relationships were generally strong when expressed as correlated evolutionary divergences. In addition, LDR was generally larger in the high-rainfall habitat than in the low-rainfall site. Accordingly, LDR can be regarded as a functional trait and an important component of the leading dimension of leaf size-twig size spectrum in plants. [ABSTRACT FROM AUTHOR]

The spindle-shaped β-FeOOH/polyacrylonitrile-amidoxime (PAN-amidhydrazone)/silver composite particles with a stable core-shell structure were successfully fabricated in the mixed solvent of dimethylformamide (DMF) and methanol using a seed-mediated growth technique, where metal silver nanoparticles tethered on β-FeOOH served as the nucleation sites for the growth of the silver nanoshell overlayer. The closed silver shell was finally formed after the seed catalyzed growing process repeated several cycles. The results of transmission electron microscopy (TEM) showed that the composite nanoparticles were spindleshape. The resulting nanoparticles showed good stability under various conditions. [ABSTRACT FROM AUTHOR]

为提高核桃壳仁混合物的分级效果，对现有核桃壳仁混合物分级设备进行三维实体建模，利用EDEM软件模拟核桃壳仁混合物的分级过程，以筛面上物料的运动速度、质量以及各等级颗粒在统计区域的数量为指标，以振幅、振动频率、振动方向角、筛面倾角为考察因素，对振动筛分级工艺进行优化。结果表明：在振动频率12 Hz、振幅5 mm、振动方向角45°、筛面倾角4°的工艺参数组合下，各等级核桃壳仁的透筛率最高，分级效果最好。In order to improve the grading effect of walnut shell and kernel mixture, the existing classification equipment of walnut shell and kernel mixture was modeled by 3D entity, and the grading process of the walnut shell and kernel mixture was simulated by EDEM. Based on the movement speed, mass of the material on the sieve surface and quantity of particles of each grade material in the statistical area as indicators, the grading process by vibrating screen was optimized with the amplitude, vibration frequency, vibrating direction angle and the sieve surface inclination as factors. The results showed that the screening rate of each grade of walnut shell and kernel was the highest and the grading effect was the best under the conditions of vibration frequency 12 Hz, amplitude 5 mm, vibrating direction angle 45°, and sieve surface inclination 4°.

The xenia effect refers to the phenomenon whereby the pollen genotype directly affects seed and fruit development during the period from fertilization to seed germination, which leads to different characteristics in phenotypic traits. The xenia effect can create differences in the endosperm and embryo formed after double fertilization and can also alter various fruit parameters, such as the fruit-ripening period; the fruit shape, size, and color; the flavor quality, such as sugars and acids; as well as the nutrient quality, such as anthocyanins. The xenia effect manifests in various ways, playing an important role in increasing the yield of fruit trees, improving fruit appearance and internal quality, as well as in directional breeding. Compared with other pomology research areas, our understanding of the xenia effect is still in its infancy. Currently, xenia is classified into two types: xenia and metaxenia. In the former, the direct effects of the pollen genotype are exhibited in the syngamous parts of the ovules; that is, the embryo and endosperm only. In the latter, the effects of the pollen genotype are demonstrated in structures other than the embryo and endosperm; that is, in tissues derived wholly from the mother plant material, in seed parts such as the nucellus and testa, as well as in the carpels and accessory tissues. However, the current classification has various shortcomings. In the present study, we propose a novel classification based on whether the appearance of xenia results from the tissue formed by double fertilization. Three xenia types are proposed: double-fertilization xenia, non–double-fertilization xenia, and combined xenia. The new classification has great theoretical and practical significance for future studies on the xenia effect and its mechanisms and also provides a more effective, broader application of xenia in improving the yield and quality of fruit trees. [ABSTRACT FROM AUTHOR]

There is a lack of an HSV-2 vaccine, in part as the result of various factors that limit robust and long-term memory immune responses at the mucosal portals of viral entry. We previously demonstrated that chemokine CCL19 augmented mucosal and systemic immune responses to HIV-1 envelope glycoprotein. Whether such enhanced immunity can protect animals against virus infection remains to be addressed. We hypothesized that using CCL19 in a fusion form to direct an immunogen to responsive immunocytes might have an advantage over CCL19 being used in combination with an immunogen. We designed two fusion constructs, plasmid (p)gBIZCCL19 and pCCL19IZgB, by fusing CCL19 to the C- or N-terminal end of the extracellular HSV-2 glycoprotein B (gB) with a linker containing two (Gly4Ser)2 repeats and a GCN4-based isoleucine zipper motif for self-oligomerization. Following immunization in mice, pgBIZCCL19 and pCCL19IZgB induced strong gB-specific IgG and IgA in sera and vaginal fluids. The enhanced systemic and mucosal Abs showed increased neutralizing activity against HSV-2 in vitro. Measurement of gB-specific cytokines demonstrated that gB-CCL19 fusion constructs induced balanced Th1 and Th2 cellular immune responses. Moreover, mice vaccinated with fusion constructs were well protected from intravaginal lethal challenge with HSV-2. Compared with pgB and pCCL19 coimmunization, fusion constructs increased mucosal surface IgA+ cells, as well as CCL19-responsive immunocytes in spleen and mesenteric lymph nodes. Our findings indicate that enhanced humoral and cellular immune responses can be achieved by immunization with an immunogen fused to a chemokine, providing information for the design of vaccines against mucosal infection by HSV-2 and other sexually transmitted viruses. [ABSTRACT FROM AUTHOR]

Recruitment of CD4+ T cells to infection areas after HSV-2 infection may be one of the mechanisms that account for increased HIV-1 sexual transmission. Lymphocytes recruited by chemokine CXCL9 are known to be important in control of HSV-2 infection in mice, although the underlying mechanism remains to be addressed. Based on our observation that CXCL9 expression is augmented in the cervical mucus of HSV-2-positive women, in this study we demonstrate that HSV-2 infection directly induces CXCL9 expression in primary cervical epithelial cells and cell lines, the principal targets of HSV-2, at both mRNA and protein levels. Further studies reveal that the induction of CXCL9 expression by HSV-2 is dependent upon a binding site for C/EBP-β within CXCL9 promoter sequence. Furthermore, CXCL9 expression is promoted at the transcriptional level through phosphor-ylating C/EBP-β via p38 MAPK pathway, leading to binding of C/EBP-β to the CXCL9 promoter. Chemotaxis assays indicate that upregulation of CXCL9 expression at the protein level by HSV-2 infection enhances the migration of PBLs and CD4+ T cells, whereas neutralization of CXCL9 or inhibition of p38-C/EBP-β pathway can significantly decrease the migration. Our data together demonstrate that HSV-2 induces CXCL9 expression in human cervical epithelial cells by activation of p38-C/EBP-β pathway through promoting the binding of C/EBP-β to CXCL9 promoter, which may recruit activated CD4+ T cells to mucosal HSV-2 infection sites and potentially increase the risk of HIV-1 sexual transmission. [ABSTRACT FROM AUTHOR]

More than 400 types of syndromic hearing loss (SHL) have been reported so far, in which Waardenburg syndrome (WS), congenital microtia syndrome (CMS), and large vestibular aqueduct syndrome (LVAS) are the most common ones in clinic. However, it is difficult to study the genetic basis and pathogenesis of SHL in a systematical way because of the strong clinical and genetic heterogeneity of SHL. Dysfunction of neural crest cells (NCC), which are caused by the gene interaction network extended from SOX10 and PAX3, are relevant to the phenotype of WS, CMS and LVAS. Our previous study also confirmed that the gene network was involved in the pathogenesis of WS. In this review, we summarize research progress in the pathogenic mechanisms of SHL resulted from defects in neural crest decelopment, and provide the gene interaction network of neural crest abnormalities resulting in SHL, and hope to provide research ideas and theoretical basis for the systematical study on pathogenesis of common SHL.