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Stress-strain relationship with soil structural parameters of collapse loess

SHAO Shengjun, LONG Jiyong, YU Qinggao

《结构与土木工程前沿（英文）》 2008年第2卷第2期页码 151-160 doi: 10.1007/s11709-008-0020-z

摘要： Through the tri-axial shearing tests of unsaturated intact loess and based on the concept of comprehensive soil structural potential, this paper reveals the changing laws of soil structural property under the tri-axial stress conditions and establishes a mathematical expression equation of structural parameters, whereby reflecting the effects of unsaturated loess water content, stress and strain states, which is introduced into the shearing stress and shearing strain relation to obtain the structural stress-strain relation. The tests reveal that the loess dilatancy is of shearing contraction and shearing expansion, whereby indicating that there is a good linear relation between the stress ratio and shearing expansion strain ratio. The larger consolidation confining pressure is, the larger the stress of shearing contraction and expansion critical point is; and the larger water content is, the smaller the strain ratio of shearing contraction and expansion critical point is. Finally, the constitutive model is established to reflect the variation in loess structure, stress-strain softening and hardening, and shearing contraction and shearing expansion features. Through the comparative analysis, the stress-strain curves described by the constitutive relationship are found to be in good conformity with test results, whereby testing the rationality of the model in this paper.

关键词： hardening shearing expansion unsaturated structural property mathematical expression

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数学推理挑战人工智能

Sean O’Neill

《工程（英文）》 2019年第5卷第5期页码 817-818 doi: 10.1016/j.eng.2019.08.009

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Blockage of receptor-interacting protein 2 expression by small interfering RNA in murine macrophages

LIU Hongchun, CAO Zhongwei, JIN Jianjun, WANG Jiyao

《医学前沿（英文）》 2008年第2卷第2期页码 166-170 doi: 10.1007/s11684-008-0030-1

摘要： This study aims to demonstrate that blocking the receptor-interacting protein2 (Rip2) expression can decrease inflammatory cytokine production by macrophage and protect mice from endotoxin lethality. Murine Rip2 small interfering RNA (siRNA) plasmids were constructed and transfected into macrophage and Rip2 expression was detected with reverse transcription-polymerase chain reaction (RT-PCR) and western blot. Cell proliferation was assayed with MTT. TNF-? concentration was assayed with ELISA and high-mobility group box 1 protein (HMGB1) level with semi-quantitative western blot after lipopolysaccharide (LPS) stimulation. LPS challenge was given after the plasmids were injected into mice and the survival rate was calculated. Rip2 siRNA plasmid could block the mRNA and protein expression of Rip2 and promote cell proliferation. Blocking Rip2 could attenuate LPS-induced TNF-? and HMGB1 production. The HMGB1 expression in the liver decreased to (40.21 ± 11.03) pg/g, and serum TNF-? level decreased to (300.43 ± 59.26) ng/L ( < 0.05). The survival rate of mice from endotoxemia was also improved ( < 0.05). The results demonstrate that Rip2 siRNA plasmid can block the expression of Rip2, decrease the production of TNF-? and HMGB1 and protect mice from fatal endotoxemia.

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MSI/LOH and extron expression of the FHIT gene in gastric carcinoma

XIAO Yuping, MAO Lili, HAN Chengbo, LI Jinyi, XU Lei, XIN Yan

《医学前沿（英文）》 2007年第1卷第1期页码 99-103 doi: 10.1007/s11684-007-0019-1

摘要： We detected loss of heterozygosity (LOH) and microsatellite instabilities (MSI), as well as extron expression of the fragile histidine triad (FHIT) gene in gastric carcinoma (GC), in order to evaluate their association with clinicopathological processes in gastric carcinogenesis. LOH and MSI of the FHIT were detected by using PCR at 4 microsatellite loci: D3S 1300, D3S 4103, D3S 1481, D3S 1234 in cancer tissues from 50 patients with primary GC, with normal mucosa acting as matched controls. FHIT transcripts were detected by nested RT-PCR in 30 cases of GC and their products were sequenced. Results show that the average frequencies of LOH and MSI of the FHIT gene in GC were 32.4% and 26.4%, respectively. There was no correlation between LOH and MSI of the FHIT gene in GC and the histological characteristics of gastric carcinoma (Bormann s or Lauren s classification). LOH of the FHIT gene in GC was related to depth invasiveness, and its frequency in GC where serosa was penetrated was significantly higher than that in GC without serosa penetration (73.5% 37.5%, <0.05). The frequency of MSI in GC without lymph node metastasis was significantly higher than that in GC with lymph node metastasis (66.7% 34.3%, <0.05). Aberrant transcripts were found in 11/30 GC tissues. Sequencing analysis of the aberrant fragments found a RT-PCR product missing exons 5 7 in one case of GC, and another product missing exons 4 7. Four of 10 (40.0%) cases of primary GC showed absent or decreased expression of the FHIT protein as compared to their matched normal tissues. The findings in this study suggest that LOH and MSI of FHIT gene may induce aberrant extron expression, which might play a role in gastric carcinogenesis.

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Gene expression disparity in giant cell tumor of bone

Xiaohua PAN, Shuhua YANG, Deming XIAO, Yong DAI, Lili REN

《医学前沿（英文）》 2009年第3卷第1期页码 49-56 doi: 10.1007/s11684-009-0012-y

摘要： The aim of this paper was to study the differential gene expression of giant cell tumor of bone (GCTB) by gene chip technology. Total RNA of 8 fresh GCTB specimens (Jaffe I∶6 cases, II∶1 case, III∶1 case; Campanacci I∶6 cases, II∶1 case, III∶1 case; Enneking Staging G T M : 5 cases, G T M : 2 cases, G T M : 1 case) and 4 normal bony callus specimens (the control group) were extracted and purified to get mRNA and then reverse transcribed to complementary DNA, respectively. Microarray screening with a set of 8064 human cDNA genes was conducted to analyze the difference among the samples and the control. The hybridization signals were scanned. The gene expression disparity between the GCTB samples and normal bony callus was significantly different ( <0.01), and the disparity of over 5-fold was found in 47 genes in the GCTB specimens, with 25 genes up-regulated and 22 down-regulated including the extracellular matrix and transforming-related genes, oncogene and its homolog genes, cytokine and its receptor genes. Specific gene spectrum associated with GCTB can be identified by cDNA microarray, which will be the foundation of progressive etiology elucidation, diagnosis and treatment of GCTB.

关键词： giant cell tumor of bone gene microarray cDNA

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Distinct gene expression pattern of mutations coordinated by target repression and promoter hypermethylation

《医学前沿（英文）》 2022年第16卷第4期页码 627-636 doi: 10.1007/s11684-020-0815-4

摘要： Runt-related transcription factor 1 (RUNX1) is an essential regulator of normal hematopoiesis. Its dysfunction, caused by either fusions or mutations, is frequently reported in acute myeloid leukemia (AML). However, RUNX1 mutations have been largely under-explored compared with RUNX1 fusions mainly due to their elusive genetic characteristics. Here, based on 1741 patients with AML, we report a unique expression pattern associated with RUNX1 mutations in AML. This expression pattern was coordinated by target repression and promoter hypermethylation. We first reanalyzed a joint AML cohort that consisted of three public cohorts and found that RUNX1 mutations were mainly distributed in the Runt domain and almost mutually exclusive with NPM1 mutations. Then, based on RNA-seq data from The Cancer Genome Atlas AML cohort, we developed a 300-gene signature that significantly distinguished the patients with RUNX1 mutations from those with other AML subtypes. Furthermore, we explored the mechanisms underlying this signature from the transcriptional and epigenetic levels. Using chromatin immunoprecipitation sequencing data, we found that RUNX1 target genes tended to be repressed in patients with RUNX1 mutations. Through the integration of DNA methylation array data, we illustrated that hypermethylation on the promoter regions of RUNX1-regulated genes also contributed to dysregulation in RUNX1-mutated AML. This study revealed the distinct gene expression pattern of RUNX1 mutations and the underlying mechanisms in AML development.

关键词： RUNX1 gene mutation acute myeloid leukemia transcriptional repression DNA methylation

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Immunohistochemical measurement and expression of Mcl-1 in infertile testes

null

《医学前沿（英文）》 2015年第9卷第3期页码 361-367 doi: 10.1007/s11684-015-0395-x

摘要：

The diagnosis of azoospermia represents a major challenge to andrologists as this condition may occur despite normal spermatogenesis and genital tracts. Myeloid cell leukemia-1 (Mcl-1) is a member of the Bcl-2 family of proteins involved in regulation of apoptosis in various cell types. This study aimed to investigate the immunohistochemical expression of Mcl-1 in testicular biopsies of subjects with azoospermia. Eighty-six cases with azoospermia were obtained from 509 infertile patients admitted to the Andrology Unit of the Zagazig University Hospitals from January 2010 to December 2011. Biopsies were diagnosed and classified using H&E-stained slide sections. The specimens were subjected to immunohistochemical staining for Mcl-1 and examined through light microscopy. Forty-five cases of maturation arrest (25 at spermatids and 20 at the spermatocytes), 31 cases of hypospermatogenesis (20 moderate and 11 severe), 5 cases of Sertoli?cell-only syndrome, 2 cases of basement membrane hyalinization, and 1 case of tubular and peritubular sclerosis were observed. Normal spermatogenesis was detected in 2 cases. A strong positive immunoreaction in Leydig cells was observed among all investigated specimens. A moderate reaction was detected in spermatocytes and spermatozoa in cases of normal spermatogenesis and hypospermatogenesis, but a negative reaction was detected in cases of maturation arrest and germ cell aplasia. Apoptosis was found to be associated with decreased rate of spermatogenesis. High apoptosis rates may result in azoospermia, which can occur despite normal spermatogenesis and absence of duct obstruction.

关键词： spermatogenesis testis Mcl-1 expression immunohistochemical study infertility

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Prediction of cutting force in turning of UD-GFRP using mathematical model and simulated annealing

Meenu GUPTA, Surinder Kumar GILL

《机械工程前沿（英文）》 2012年第7卷第4期页码 417-426 doi: 10.1007/s11465-012-0343-2

摘要：

Glass fiber reinforced plastics (GFRPs) composite is considered to be an alternative to heavy exortic materials. According to the need for accurate machining of composites has increased enormously. During machining, the obtaining cutting force is an important aspect. The present investigation deals with the study and development of a cutting force prediction model for the machining of unidirectional glass fiber reinforced plastics (UD-GFRP) composite using regression modeling and optimization by simulated annealing. The process parameters considered include cutting speed, feed rate and depth of cut. The predicted values radial cutting force model is compared with the experimental values. The results of prediction are quite close with the experimental values. The influences of different parameters in machining of UD-GFRP composite have been analyzed.

关键词： UD-GFRP ANOVA radial cutting force PCD tool Taguchi method regression analysis simulated annealing multi objective techniques

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Construction of a universal recombinant expression vector that regulates the expression of human lysozyme

Shen LIU, Shengzhe SHANG, Xuezhen YANG, Huihua ZHANG, Dan LU, Ning LI

《农业科学与工程前沿（英文）》 2018年第5卷第3期页码 382-389 doi: 10.15302/J-FASE-2018211

摘要：

The mammary gland provides a novel method for producing recombinant proteins in milk of transgenic animals. A key component in the technology is the construction of an efficient milk expression vector. Here, we established a simple method to construct a milk expression vector, by a combination of homologous recombination and digestion-ligation. Our methodology is expected to have the advantages of both plasmid and bacterial artificial chromosome (BAC) vectors. The BAC of mouse whey acidic protein gene (mWAP) was modified twice by homologous recombination to produce a universal expression vector, and the human lysozyme gene (hLZ) was then inserted into the vector by a digestion-ligation method. The final vector containing the 8.5 kb mWAP 5′ promoter, 4.8 kb hLZ genomic DNA, and 8.0 kb mWAP 3′ genomic DNA was microinjected into pronuclei of fertilized mouse embryos, to successfully generate two transgenic mouse lines that expressed recombinant human lysozyme (rhLZ) in milk. The highest expression level of rhLZ was 0.45 g·L⁻¹, and rhLZ exhibited the same antibacterial activity as native hLZ. Our results have provided a simple approach to construct a universal milk expression vector, and demonstrated that the resulting vector regulates the expression of hLZ in milk.

关键词： BAC recombinant methods gene expression human lysozyme transgenic mice milk expression vector

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Relationship of adrenomedullin expression and microvessel density and prognosis in smooth muscle tumor

JIANG Yuan, TIAN Xuehong, YUAN Jie, JIN Yuemei, TAN Yusong

《医学前沿（英文）》 2007年第1卷第4期页码 398-400 doi: 10.1007/s11684-007-0077-4

摘要： The aim of this paper was to investigate the relationship between the expression of adrenomedullin (ADM) and microvessel density (MVD) and prognosis in smooth muscle tumor of uterus. The expression of ADM was detected using immunohistochemical staining in specimens from 15 normal controls, 28 cases of uterine leiomyoma (LE) and 19 cases of uterine leiomyosarcoma (LES). The MVD was assayed by immunostainting with CD. There was a positive correlation between the ADM expression and MVD in LE and LES respectively ( = 0.823, <0.01; = 0.793, <0.01). The expression of ADM in LE was statistically lower than that in LES (<0.05). There was a positive correlation between the ADM expression and mitotic figures in LES (<0.05): the more mitotic figures, the higher levels of the ADM expression and poor prognosis. The ADM is an important angiogenic factor in smooth muscle tumor of uterus. The ADM can be used as an accessory marker in estimating the malignant potency of LE and judging the pro gnosis of LES, and as a novel molecular target of anti-angiogenic and anticarcinogenic strategies.

关键词： anticarcinogenic microvessel density malignant potency muscle uterine leiomyosarcoma

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大型农业生态工程的数学模型

卞有生,王天喜,陈正龙,崔斌

《中国工程科学》 2002年第4卷第7期页码 17-22

摘要：

文章在对胜利油田生态农场系统结构分析的基础上，根据农场规划目标，建立了由投入产出模型和线性规划模型相结合的经济发展数学模型。应用该模型指导农场的经济建设，取得了极好的效果，证明所建立的模型是正确的。

关键词：农业生态工程数学模型胜利油田

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Heterologous expression of signal protein 14-3-3 in and the subsequent immune response in mice

ZHENG Meijuan, SHEN Jilong, LUO Qingli, XU Yuanhong

《医学前沿（英文）》 2008年第2卷第1期页码 95-99 doi: 10.1007/s11684-008-0017-y

摘要： Schistosomiasis japonica, a zoonosis caused by , is endemic to the Philippines and China. Several vaccine candidates have been identified and tested in different animal models, but it is still unclear which will be optimal for testing in the field. Therefore, new antigens and strategies are necessary for vaccine development against schistosomiasis japonica. The Sj14-3-3 gene was amplified and subcloned into the expression vector pPICZ?-B and transformed into X-33 by electroporation. Three transformants were induced with methanol. The cultural supernatant was collected and tested by SDS-PAGE and Western blotting. The protein of rSj14-3-3 was prepared and purified and BALB/c mice were immunized which was followed by a challenging infection. The immuno-protection was then evaluated. The Sj14-3-3 gene was expressed and secreted into the medium and its molecular weight was about 35000 as determined by SDS-PAGE. Western blotting showed that the protein had a high specificity against mouse-anti-Sj14-3-3 monoclonal antibody and rSj14-3-3 had a promising immune reactivity. The results of the immuno-protective experiments revealed that the worm reduction was 26.0%, 32.2%, and 36.8%, respectively. The number of eggs in liver tissue was reduced by 36.8%, 43.2%, and 46.1%, respectively. The recombinant Sj14-3-3 of eukaryotic expression in was successfully harvested. The molecular vaccine of Sj14-3-3 could partially induce resistance to the infection with in BALB/c mice. The recombinant protein Sj14-3-3 has promising immunological potentials for further approach to the diagnosis and development of molecular vaccine.

关键词： development challenging rSj14-3-3 resistance cultural supernatant

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Increased expression of coronin-1a in amyotrophic lateral sclerosis: a potential diagnostic biomarker

《医学前沿（英文）》 2022年第16卷第5期页码 723-735 doi: 10.1007/s11684-021-0905-y

摘要： Amyotrophic lateral sclerosis (ALS) is the most common motor neuron disease. At present, no definite ALS biomarkers are available. In this study, exosomes from the plasma of patients with ALS and healthy controls were extracted, and differentially expressed exosomal proteins were compared. Among them, the expression of exosomal coronin-1a (CORO1A) was 5.3-fold higher than that in the controls. CORO1A increased with disease progression at a certain proportion in the plasma of patients with ALS and in the spinal cord of ALS mice. CORO1A was also overexpressed in NSC-34 motor neuron-like cells, and apoptosis, oxidative stress, and autophagic protein expression were evaluated. CORO1A overexpression resulted in increased apoptosis and oxidative stress, overactivated autophagy, and hindered the formation of autolysosomes. Moreover, CORO1A activated Ca²⁺-dependent phosphatase calcineurin, thereby blocking the fusion of autophagosomes and lysosomes. The inhibition of calcineurin activation by cyclosporin A reversed the damaged autolysosomes. In conclusion, the role of CORO1A in ALS pathogenesis was discovered, potentially affecting the disease onset and progression by blocking autophagic flux. Therefore, CORO1A might be a potential biomarker and therapeutic target for ALS.

关键词： amyotrophic lateral sclerosis coronin-1a autophagy pathogenesis

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Cooling strategies and transport theories for brain hypothermia resuscitation

LIU Jing

《能源前沿（英文）》 2007年第1卷第1期页码 32-57 doi: 10.1007/s11708-007-0004-z

摘要： The brain is one of the most important organs in a biological body whose normal function depends heavily on an uninterrupted delivery of oxygen. Unlike skeletal muscles that can survive for hours without oxygen, neuron cells in the brain are easily subjected to an irreversible damage within minutes from the onset of oxygen deficiency. With the interruption of cardiopulmonary circulation in many cardiac surgical procedures or accidental events leading to cerebral circulation arrest, an imbalance between energy production and consumption will occur which causes a rapid depletion of oxygen due to the interrupted blood-flow to the brain. Meanwhile, the cooling function of the blood flow on the hot tissue will be stopped, while metabolic heat generation in the tissues still keeps running for awhile. Under such adverse situations, the potential for cerebral protection through hypothermia has been intensively investigated in clinics by lowering brain temperature to restrain the cerebral oxygen demands. The reason can be attributed to the decreased metabolic requirements of the cold brain tissues, which allows a longer duration for the brain to endure reduced oxygen delivery. It is now clear that hypothermia would serve as the principal way for neurologic protection in a wide variety of emergency medicines, especially in cerebral damage, anoxia, circulatory arrest, respiratory occlusion, etc. However, although brain cooling has been found uniquely significant in clinical practices, the serious lack of knowledge on the mechanisms involved prevents its further advancement in brain resuscitation. Compared with the expanded trials in clinics, only very limited efforts were made to probe the engineering issues involved, which turns out to be a major obstacle for the successful operation of brain hypothermia resuscitation. From the viewpoint of biothermal medical engineering, the major theories and strategies for administering brain cooling can generally be classified into three categories: heat transfer, oxygen transport and cooling strategy. Aiming to provide a complete overview of the brain hypothermia resuscitation, this article comprehensively summarizes the recent progresses made in theoretical, practical and experimental techniques in the area. Particularly, attention is paid to the mathematical models to quantify the heat and oxygen transport inside the cerebral tissues. Typical cooling strategies to effectively lower brain temperature and thus decrease oxygen consumption rate in the cerebral tissues are analyzed. Approaches to deliver oxygen directly to the target tissues are discussed. Meanwhile, some future efforts worth pursuing within the area of brain cooling are suggested.

关键词： mathematical interruption hypothermia metabolic generation

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Effect of arsenic trioxide on proliferation and apoptosis of U266 cells and its relationship with the expression

ZHAN Rong, YU Qinghong, HUANG Haobo

《医学前沿（英文）》 2008年第2卷第4期页码 356-360 doi: 10.1007/s11684-008-0068-0

摘要： The aim of this article is to explore the effect of arsenic trioxide (AsO) on the proliferation and apoptosis of myeloma cell line U266 and its relationship with the expression variation of vascular endothelial growth factor (VEGF). The viability and apoptosis of U266 cells were observed by methylthiazolyl- tetrazolium (MTT) assay and terminal-deoxynucleotidyl transferase mediated nick end labeling (TUNEL). The effect of AsO on the VEGF expression of U266 cells were tested by enzyme linked immunosorbent assay (ELISA) and reverse transcription-polymerase chain reaction (RT-PCR) analysis. We found that AsO could significantly inhibit the growth of U266 cells, and the concentration for 50% growth inhibition (IC) was 2 ?mol/L. After treatment with 2, 5, 10 ?mol/L AsO for 36 hours, dose-dependent apoptosis of U266 cells was observed. After treatment with 2, 5, 10 ?mol/L AsO for 72 hours, a dose-dependent reduction of VEGF in the supernatant of U266 cells culture was found. As far as single cells are concerned, nevertheless, the expression of VEGF mRNA did not vary. So we draw the conclusion that AsO could induce the apoptosis of U266 cells and inhibit their proliferation, decrease the tumor load, and lead to the reduction of VEGF in the culture supernatant, but not change the expression of VEGF in single U266 cells.

关键词： VEGF expression expression variation culture supernatant labeling concentration