典当行与商业银行之服务对象细分机理探析

我国是典当行出现最早的国家之一。建国初期．典当曾被认为是剥削制度的残渣余孽而遭到禁止。改革开放以后．为了满足国民经济快速发展的需要．在党和政府一系列的政策的大力支持下．典当行又于20世纪80年代末期重新出现并开始快速发展。

Molecular mechanism of TNF signaling and beyond

Tumor necrosis factor (TNF) is a proinflammatory cytokine that plays a critical role in diverse cellular events, including cell proliferation, differentiation and apoptosis. TNF is also involved in many types of diseases. In recent years, the molecular mechanisms of TNF functions have been intensively investigated. Studies from many laboratories have demonstrated that the TNF-mediated diverse biological responses are achieved through activating multiple signal- ing pathways. Especially the activation of transcription factors NF-κB and AP-1 plays a critical role in mediating these cellular responses. Several proteins, including FADD, the death domain kinase RIP and the TNF receptor associated factor TRAF2 have been identified as the key effectors of TNF signaling. Recently, we found that the effector mol- ecules of TNF signaling, such as RIP and TRAF2, are also involved in other cellular responses. These finding suggests that RIP and TRAF2 serve a broader role than as just an effector of TNF signaling.

Taurolithocholate impairs bile canalicular motility and canalicular bile secretion in isolated rat hepatocyte couplets

AIM: To investigate the effects of taurolithocholate (TLC)on the canalicular motility in isolated rat hepatocyte cou-plets (IRHC).METHODS: TLC was added to IRHC at concentrationsof 10 and 50 μmol/L, respectively. In each group, fi vetime-lapse movies containing 3 representative bile cana-liculi were taken under phase-contrast microscopy for12 h. The number of bile canalicular contractions andthe intervals between consecutive canalicular contrac-tions were calculated. Furthermore, the effects of TLC onIRHC were examined by transmission electron micros-copy.RESULTS: The bile canalicular contractions were spon-taneous and forceful in the controls. Active vesicularmovement was observed in the pericanalicular region.Immediately after the addition of TLC, the bile canaliculiwere deformed, and canalicular bile was incorporatedinto the vacuoles. The canaliculi were gradually dilated,and canalicular contractions were markedly inhibited byTLC. The vesicular movements became extremely slowin the pericanalicular region. The number of canalicularcontractions significantly decreased in the TLC-treatedgroups, as compared with that in the controls. The timeintervals were prolonged, as the TLC dosage increased,indicating that bile secretion into the canaliculi wasimpaired with TLC. Transmission electron microscopyrevealed the lamellar transformation of the canalicularmembranes in IRHC treated with TLC.CONCLUSION: TLC impairs both the bile canalicularcontractions and the canalicular bile secretion, possiblyby acting directly on the canalicular membranes in TLC-induced cholestasis.

Preparation of ultrafine silver powders with controllable size and morphology

The ultrafine silver powders were prepared by liquid reduction method using Arabic gum as dispersant.The effects of different dispersants,pH values,and temperature on the morphology and particle size of silver powders were investigated.It is found that Arabic gum can better adsorb on silver particles via chemical adsorption,and it shows the best dispersive effect among all the selected dispersants.The particle size of silver powders can be finely tuned from 0.34 to 4.09μm by adjusting pH values,while the morphology of silver powders can be tuned by changing the temperature.The silver powders with high tap density higher than 4.0 g/cm3 were successfully prepared in a wide temperature range of 21.8-70°C.Especially,the tap density is higher than 5.0 g/cm3 when the temperature is optimized to be 50°C.The facile process and high silver concentration of this method make it a promising way to prepare high quality silver powders for electronic paste.

Calcium signaling in cholangiocytes

Cytosolic Ca^2＋ is an important second messenger in virtually every type of cell. Moreover, Ca^2＋ generally regulates multiple activities within individual cells. This article reviews the cellular machinery that is responsible for Ca^2＋ signaling in cholangiocytes. In addition, two Ca^2＋-mediated events in cholangiocytes are discussed： bicarbonate secretion and apoptosis. Finally, emerging evidence is reviewed that Ca^2＋ signaling is involved in the pathogenesis of diseases affecting the biliary tree and that Ca^2＋ signaling pathways can be manipulated to therapeutic advantage in the treatment of cholestatic disorders.

Genome-wide comparative analysis of type-A Arabidopsis response regulator genes by overexpression studies reveals their diverse roles and regulatory mechanisms in cytokinin signaling

Cytokinin is a critical growth regulator for various aspects of plant growth and development. In Arabidopsis, cytokinin signaling is mediated by a two-component system-based phosphorelay that transmits a signal from the receptors, through histidine phosphotransfer proteins, to the downstream response regulators （ARRs）. Of these ARRs, type-A ARR genes, whose transcription can be rapidly induced by cytokinin, act as negative regulators of eytokinin signaling. However, because of functional redundancy, the function of type-A ARR genes in plant growth and development is not well understood by analyzing loss-of-function mutants. In this study, we performed a comparative functional study on all ten type-A ARR genes by analyzing transgenic plants overexpressing these ARR genes fused to a MYC epitope tag. Overexpression of ARR genes results in a variety of cytokinin-associated phenotypes. Notably, overexpression of different ARR transgenes causes diverse phenotypes, even between phylogenetically closely-related gene pairs, such as within the ARR3-ARR4 and ARR5-ARR6 pairs. We found that the accumulation of a subset of ARR proteins （ARR3, ARR5, ARR7, ARR16 and ARR17; possibly ARR8 and ARR15） is increased by MG132, a specific proteasomal inhibitor, indicating that stability of these proteins is regulated by proteasomal degradation. Moreover, similar to that of previously characterized ARR5, ARR6 and ARR7, stability of ARR16 and ARR17, possibly including ARR8 and ARR15, is regulated by cytokinin. These results suggest that type-A ARR proteins are regulated by a combinatorial mechanism involving both the cytokinin and proteasome pathways, thereby executing distinctive functions in plant growth and development.

Advance in the Studies on Small Cell Neuroendocrine Carcinoma of the Paranasal Sinuses

Small cell neuroendocrine carcinoma (SCNEC) of the paranasal sinuses is extremely rare,with an unclear pathogenesis.The presence of neuroendocrine granules is suggestive of neuroendocrine differentiation.It was reported that this disease relates to the presence of accessory salivary glands,and some basic research has shown that it might originate from the multi-potent stem cells.There are no specific clinical symptoms but rhinal and ophthalmological symptoms are found in most cases.Diagnosis mainly depends on histopathological manifestations,immunohistochemical results and features of the electron microscopic ultra-structure.Pathological differentiation from poorly differentiated squamous carcinoma,melanoma,esthesioneuroblastoma and neuroglioma etc.is needed.No unified regimen has been employed in treating the disease.At present,combined therapy has a manifest therapeutic effect,such as success with the 2003 French regimen.Tumor relapse is common and prognosis is poor.A complete combined treatment plan will be helpful to improve the prognosis.

Mechanism Analyses for Elucidating the Role of LOXL2 Silencing in Hepatocellular Carcinoma

The paper aimed to study the effect of lysyl oxidase-like 2 （LOXL2） on hepatocellular carcinoma （HCC） and explore the biological mechanisms of tumorigenicity and progression in HCC. The authors used four HCC cell lines to identify LOXL2. A lentiviral vector containing LOXL2-siRNA was constructed to silence the LOXL2 gene in SMMC-7721 cell line, and mRNA of the target gene was detected by real-time polymerase chain reaction （RT-PCR）. The effect of LOXL2 silencing on the growth of SMMC-7721 cells was explored with flow cytometry profiling and BrdU labeling. Downstream genes of LOXL2 were selected by microarray and verified by Western Blotting. In the results, LOXL2 expression was significantly up-regulated in four types of HCC cell lines, therefore, SMMC-7721 cell line was selected for further exploration. When SMMC-7721 cell line was infected with LOXL2-siRNA, the expression of LOXL2 mRNA decreased. The silencing of LOXL2 resulted in the cell cycle arrest at the G 1-phase, the increased apoptosis and the decreased growth of SMMC-7721 cells on the indicated days by BrdU. Moreover, the MDM2, BIRC3, CDC42, FOS and TGFBR2 genes were selected and verified to be the downstream genes of LOXL2. In conclusion, LOXL2 contributes to the genesis and progression of HCC cells and works by regulating downstream genes of LOXL2 in certain pathways. Therefore, LOXL2 may play an important role in the progression and prognosis of HCC.

A Study of Molecular Resection Margins for Esophageal Squamous Cell Carcinoma Using Large Pathologic Sections

OBJECTIVE It has been shown that application of molecular biological techniques to surgical margins of some cancers could predict risk of local recurrence. However, the optimal length of surgical resection with tumor-free surgical margins for esophageal squamous cell carcinoma （ES- CC） is unknown. This study was conducted to evaluate the optimal length of surgical resection for ESCC with molecularly tumor-free surgical margins marked by p53 and Ki67.METHODS Surgical specimens from 70 patients with ESCC were collected for study. The lengths of the upper margin, tumor, and lower margin of every specimen were measured during the operation. Each specimen was divided into three large pathologic sections, stained with H＆E and immunohistochemically for p53 and Ki67, and examined microscopically. The lengths of the upper and lower resection ends were measured for p53 and Ki67 positive expression. The actual surgical lengths were calculated by the principle of rational shrinkage.RESULTS All surgical margins were histologically tumor-free, while the positive rates of p53 and Ki67 were 66% and 54%. The positive rates of p53 and Ki67 in the upper resecti0n end were 17% and 20%. The mean lengths of the upper resection end showing p53 and Ki67 positive expression were 1.08±1.12 cm and 1.64±1.01 cm, and the maximum lengths were 3.73 cm and 3.26 cm. The positive,rates of p53 and Ki67 in the lower resection end were 20% and 23%. The mean lengths of the lower resection end of p53 and Ki67 with positive expression were 1.11±1.15 cm and 1.34±0.94 cm, and the maximum lengths were 3.73 cm and 3.61 cm.CONCLUSION The optimal length of surgical resection with molecularly tumor-free surgical margins of ESCC is not more than 5 cm.

ANALYSIS OF EFFICACY IN TREATMENT OF LOW-RISK WELL-DIFFERENTIATED THYROID CANCER WITHOUT CERVICAL LYMPH NODE INVOLVEMENT: 42 CASES REPORT

Objective To assess the more appropriate surgical treatment for low-risk group differentiated thyroid cancer. Methods A total of 42 low-risk patients with DTC, according to the AMES system (male, n = 6; female, n = 36) , were chosen for total thyroidectomy or subtotal thyroidectomy with center compartment lympha-dectomy. Results Nineteen patients had cervical lymph node involvement. Two patients had recurrent nerve injured. One patient had hypoparathyroidism. There were no mortality or local lymph recurrent up to present. Conclusion Total thyroidectomy or subtotal thyroidectomy with prophylactic center compartment lymphadectomy is an appropriate approach for the treatment of low-risk group differentiated thyroed cancer, to prevent recurrent and improve life quality.

Changes of gap junctional intercellular communication in detrusor instability

Objective: To demonstrate the functional changes of gap junctional mediation of intercellular communication in detrusor instability (DI) and its mechanisms. Methods: The function of gap junctional intercellular communication in the cultured bladder detrusor cells was detected by fluorescence redistribution after photobleaching. Results: At the fourth minute after bleaching, the mean fluorescences recovery rates of DI group bladder detrusor cells were (35 791±0 836)%, that of control group (8 645±0 673)%. The mean fluorescence recovery rates of DI group were significantly higher than those of control group ( P <0 01). Conclusion: It shows that the increase of intercellular excitatory communication is one of the important reasons of pathogenesis of DI.

Molecular mechanism of damage and repair of mouse thymus lymphocytes induced by radiation

OBJECTIVE: To investigate the role of apoptosis in radiation-induced mouse thymus lymphocyte damage and repair and provide the basis for understanding the molecular mechanism of radiation-induced lymphocyte damage and repair as well as the prevention and treatment of acute radiation sickness. METHODS: We studied the dynamic changes of apoptosis of mouse thymus lymphocytes and the expression of bax and bcl-2 gene products after 2, 4, 6 and 8 Gy of whole body gamma-irradiation using in situ terminal labeling, DNA electrophoresis and immunohistochemical techniques. RESULTS: At the early stage after irradiation, the percentage of apoptotic lymphocytes increased rapidly in accordance with the increasing of radiation doses, while the counts of the thymus and peripheral lymphocytes decreased sharply, showing an opposite change to lymphocyte apoptosis. After 6 Gy gamma-irradiation, typical morphological characteristics of thymus apoptotic lymphocytes in early, middle and late stages were found by transmission electron microscopy. The thymus lymphocytes displayed characteristic DNA ladders 4 hr and 8 hr after 2-6 Gy gamma-irradiation,using DNA gel electrophoresis techniques. Abnormal expression of bcl-2 and bax gene products were shown in irradiated lymphocytes. CONCLUSIONS: Apoptosis plays an important role in the process of radiation-induced mouse thymus lymphocyte damage and repair. Bcl-2 and Bax proteins may regulate the process of lymphocyte apoptosis.

Paneth cells: the hub for sensing and regulating intestinal flora

The complex interplay between symbiotic bacteria and host immunity plays a key role in shaping intestinal homeostasis and maintaining host health. Paneth cells, as one of the major producers of antimicrobial peptides in the intestine under steady-state conditions, play a vital role in regulating intestinal flora. Many studies on inflammatory bowel disease(IBD)-associated genes have put Paneth cells at the center of IBD pathogenesis. In this perspective, we focus on mechanistic studies of different cellular processes in Paneth cells that are regulated by various IBD-associated susceptibility genes, and we discuss the hypothesis that Paneth cells function as the central hub for sensing and regulating intestinal flora in the maintenance of intestinal homeostasis.

Exploring the mechanism of Peganum harmala L.seeds on hepatocellular carcinoma based on network pharmacology and molecular docking

Peganum harmala L.is a medicinal plant,and its seeds have been used to treat gastrointestinal cancer and malaria for a long time in North-Western China.In the present study,we aimed to probe the potential molecular targets and pharmacological mechanisms of Peganum harmala L.seeds(PHS)on hepatocellular carcinoma(HCC)using network analysis and molecular docking.First,the chemical ingredients of PHS were obtained from TCMID and BATMAN-TCM databases,and the effective ingredients were screened by SwissADME.Furthermore,the target information of the effective ingredients was acquired from PharmMapper and SwissTargetPrediction databases.Secondly,HCC-related targets were obtained from Liverome,DisGeNET,and GeneCards databases.The intersection with the PHS was obtained.The“compounds-targets”was drawn using Cytoscape software,and PPI network diagrams were drawn using their intersection targets.GO analysis and KEGG enrichment analysis were carried out using the DAVID database.Finally,molecular docking was conducted between protein receptors and the active components using AutoDockTools.Our results showed 105 intersection targets of PHS with HCC.Moreover,10 core targets included ALB,AKT1,EGFR,CASP3,SRC,ESR1,MAPK3,MMP9,ANXA5,and MAPK1.Besides,404 GO functional annotations were obtained,including 287 biological processes,37 cell compositions,and 80 molecular functions.In addition,110 signaling molecules and pathways,including chemical oncogene receptors,PI3K-Akt pathway,HCC,and hepatitis B,were identified.The molecular docking results showed that the binding energies of the 10 core targets and the 12 active components were all less than–5 kcal/mol.In conclusion,this study expounded on the“component-target-pathway”interaction mechanism of PHS for the treatment of HCC,and it also provided a scientific basis for the clinical application of PHS.

The formation of liquid bridge in different operating modes of AFM

The liquid bridge is one of the principal factors that cause artifacts in ambient-pressure atomic force microscope(AFM) images.Additionally, it is the main component of the adhesion force in ambient conditions. To understand the AFM imaging mechanism and the sample characteristics, it is essential to study the liquid bridge. This study interprets the physical mechanism involved in liquid bridge formation, which is composed of three different physical processes: the squeezing process, capillary condensation,and liquid film flow. We discuss the contributions of these three mechanisms to the volume and the capillary force of the liquid bridge in different AFM operation modes.