[Applications of stem cell disease models in liver metabolic research and drug development].

The high failure rate of the new drug development has been well recognized. Relying on the pre-clinical data obtained from animal experiments will inevitably cause a low concordance with human clinical trials, which will eventually lead to new drug development failure. Employing human induced pluripotent stem cells (iPSCs) or adult stem cells to simulate disease models can not only provide an unlimited cell materials, but also faithfully represent the genetic background of a certain disease, when iPSCs or adult stem cells derived from patients with a specific disease genetic variation are applied. In addition, gene editing methods can be used to introduce genetic variants of interest into stem cells to generate disease models. Furthermore, by establishing a cell bank with a population of iPSCs in petri dish, in vitro human genetic studies can be carried out in these cells, with GWAS and QTL studies applied to identify genetic variants that are associated with drug sensitivity or cytotoxicity. These efforts may offer valuable information for the recruitment of suitable patients for clinical trials. Therefore, stem cell-derived disease models can provide valuable resources for the pathophysiological studies of diseases as well as the drug development. In this review, we will briefly introduce the development of the liver disease models derived from stem cells and their applications in disease study and drug development.

Acid-sensing ion channel 1a mediates acid-induced pyroptosis through calpain-2/calcineurin pathway in rat articular chondrocytes.

The pyroptosis is a causative agent of rheumatoid arthritis, a systemic autoimmune disease merged with degenerative articular cartilage. Nevertheless, the precise mechanism of extracellular acidosis on chondrocyte pyroptosis is largely unclear. Acid-sensing ion channels (ASICs) belong to an extracellular H+ -activated cation channel family. Accumulating evidence has highlighted activation of ASICs induced by extracellular acidosis upregulate calpain and calcineurin expression in arthritis. In the present study, to investigate the expression and the role of acid-sensing ion channel 1a (ASIC1a), calpain, calcineurin, and NLRP3 inflammasome proteins in regulating acid-induced articular chondrocyte pyroptosis, primary rat articular chondrocytes were subjected to different pH, different time, and different treatments with or without ASIC1a, calpain-2, and calcineurin, respectively. Initially, the research results showed that extracellular acidosis-induced the protein expression of ASIC1a in a pH- and time-dependent manner, and the messenger RNA and protein expressions of calpain, calcineurin, NLRP3, apoptosis-associated speck-like protein, and caspase-1 were significantly increased in a time-dependent manner. Furthermore, the inhibition of ASIC1a, calpain-2, or calcineurin, respectively, could decrease the cell death accompanied with the decreased interleukin-1ß level, and the decreased expression of ASIC1a, calpain-2, calcineurin, and NLRP3 inflammasome proteins. Taken together, these results indicated the activation of ASIC1a induced by extracellular acidosis could trigger pyroptosis of rat articular chondrocytes, the mechanism of which might partly be involved with the activation of calpain-2/calcineurin pathway.

Self-assembly of biological networks via adaptive patterning revealed by avian intradermal muscle network formation.

Networked structures integrate numerous elements into one functional unit, while providing a balance between efficiency, robustness, and flexibility. Understanding how biological networks self-assemble will provide insights into how these features arise. Here, we demonstrate how nature forms exquisite muscle networks that can repair, regenerate, and adapt to external perturbations using the feather muscle network in chicken embryos as a paradigm. The self-assembled muscle networks arise through the implementation of a few simple rules. Muscle fibers extend outward from feather buds in every direction, but only those muscle fibers able to connect to neighboring buds are eventually stabilized. After forming such a nearest-neighbor configuration, the network can be reconfigured, adapting to perturbed bud arrangement or mechanical cues. Our computational model provides a bioinspired algorithm for network self-assembly, with intrinsic or extrinsic cues necessary and sufficient to guide the formation of these regenerative networks. These robust principles may serve as a useful guide for assembling adaptive networks in other contexts.

[Evaluation of continuous curvilinear buccal-cervical incision in combined radical resection of buccal cancer].

PURPOSE: To evaluate the clinical effect of continuous curvilinear buccal-cervical incision in combined radical resection of buccal cancer. METHODS: From January 2015 to December 2018, a total of 87 patients with buccal cancer were collected, of whom 42 underwent continuous curvilinear buccal-cervical incision (experimental group) and 45 underwent conventional cervical T shaped incision combined with a buccal incision (control group). Exposure of surgical filed in two groups was evaluated. The length of incision, duration of radical resection, and the incidence of postoperative complications were compared between two groups. The patients were followed-up for 7-43 months. Modified vancouver scar scale (VSS) and University of Washington Quality of Life (UW-QOL) were used to evaluate the postoperative scar and quality of life in both groups. Statistical analysis was performed on the data using SPSS 22.0 software package. RESULTS: The length of the incision in the experimental group was (36.40±5.08) cm, which was shorter than that of the control group (39.93±5.22) cm. Duration of combined radical resection in the experimental group was shorter than that of the control group. The incidence of neck complications in the experimental group was lower than that of the control group. The postoperative scar assessment and quality of life of the experimental group were better than that of the control group. The difference was statistically significant (P<0.05). There was no significant difference between the two groups in terms of the exposure of the surgical field, postoperative recurrence and metastasis rate. CONCLUSIONS: Continuous curvilinear buccal-cervical incision has good exposure of the surgical field and shorter duration of radical resection, which ensures en bloc resection of tumor and cervical lymph nodes. It limits the formation of skin cicatrix, reduces the occurrence of postoperative complications and results in a good aesthetic and functional effect, therefore it is a recommended incision for clinical practice.

[The influence of different modes of delivering postoperative instructions on the side effects of wisdom tooth extraction].

PURPOSE: To study the difference between the distinct ways of delivering postoperative instructions to reduce the side effects of wisdom tooth extraction, including pain, bleeding and swelling, and improve the degree of satisfaction of the patients. METHODS: A group of 150 patients who underwent wisdom tooth extraction in the Department of Oral and Maxillofacial Surgery of Xiangya Hospital, Central South University between Jan. 2018 to Oct. 2018 were selected in this research randomly. They were divided into 3 groups randomly and 50 patients in each group. Patients in group 1 received verbal postoperative instructions, patients in group 2 received written postoperative instructions, and patients in group 3 received verbal plus written postoperative instructions. The information of age, sex and education level was collected for each patient. The side effects of pain, bleeding and swelling, and the satisfactory degree of the patients were recorded 7 days after surgery. SPSS 22.0 software package was used for statistical analysis. RESULTS: There were 81 women and 69 men among 150 patients. The mean age was 24.6±2.6 years. The results showed that the degree of pain of group 1 was significantly higher than group 2 (P=0.001) and group 3 (P=0.000). The satisfactory degree of group 1 was the lowest, and group 3 was the highest. CONCLUSIONS: The way of delivering postoperative instructions affects pain and satisfactory degree after wisdom tooth extraction.

Interleukin-1ß and tumor necrosis factor-α augment acidosis-induced rat articular chondrocyte apoptosis via nuclear factor-kappaB-dependent upregulation of ASIC1a channel.

The acute-phase proinflammatory cytokines interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α) demonstrate high-level expression and pleiotropic biological effects, and contribute to the progression and persistence of rheumatoid arthritis (RA). Acid hydrarthrosis is also an important pathological characteristic of RA, and the acid-sensing ion channel 1a (ASIC1a) plays a critical role in acidosis-induced chondrocyte cytotoxicity. However, the roles of IL-1ß and TNF-α in acid-induced apoptosis of chondrocytes remain unclear. Rat adjuvant arthritis and primary articular chondrocytes were used as in vivo and in vitro model systems, respectively. ASIC1a expression in articular cartilage was increased and highly colocalized with nuclear factor (NF)-κB expression in vivo. IL-1ß and TNF-α could upregulate ASIC1a expression. These cytokines activated mitogen-activated protein kinase and NF-κB pathways in chondrocytes, while the respective inhibitors of these signaling pathways could partially reverse the ASIC1a upregulation induced by IL-1ß and TNF-α. Dual luciferase and gel-shift assays and chromatin immunoprecipitation-polymerase chain reaction demonstrated that IL-1ß and TNF-α enhanced ASIC1a promoter activity in chondrocytes by increasing NF-κB DNA-binding activities, which was in turn prevented by the NF-κB inhibitor ammonium pyrrolidinedithiocarbamate. IL-1ß and TNF-α also decreased cell viability but enhanced LDH release, intracellular Ca2+ concentration elevation, loss of mitochondrial membrane potential, cleaved PARP and cleaved caspase-3/9 expression, and apoptosis in acid-stimulated chondrocytes, which effects could be abrogated by the specific ASIC1a inhibitor psalmotoxin-1 (PcTX-1), ASIC1a-short hairpin RNA or calcium chelating agent BAPTA-AM. These results indicate that IL-1ß and TNF-α can augment acidosis-induced cytotoxicity through NF-κB-dependent up-regulation of ASIC1a channel expression in primary articular chondrocytes.

ASIC2a overexpression enhances the protective effect of PcTx1 and APETx2 against acidosis-induced articular chondrocyte apoptosis and cytotoxicity.

Acid hydrarthrosis is another important pathological character in rheumatoid arthritis (RA), and acid-sensing ion channel 1a (ASIC1a) plays a destructive role in acidosis-induced articular chondrocyte cytotoxicity. Recently, ASIC2a has been reported to possess neuroprotective effect on acidosis-induced injury of neuronal cells. However, whether ASIC2a has an enhanced effect on the protective effect of blocking ASIC1a and ASIC3 against acid-induced chondrocyte apoptosis is still unclear. The aim of present study was to investigate the chondroprotective effect of ASIC2a with PcTx1 (ASIC1a specific blocker) and APETx2 (ASIC3 specific blocker) on acidosis-induced chondrocyte apoptosis. Our results revealed that acid (pH 6.0) decreased the cell viability and induced apoptosis of articular chondrocytes. PcTx1 and APETx2 combination significantly attenuated acidosis-induced chondrocyte cytotoxicity due to inhibit apoptosis, and this role could be enhanced by ASIC2a overexpression compared with the PcTx1 and APETx2 combination alone group. Moreover, both the [Ca2+]i levels and the levels of phosphorylated ERK1/2 as well as p38 were further reduced in acidosis-induced chondrocytes after ASIC2a overexpression in the presence of PcTx1 and APETx2. Furthermore, ASIC2a overexpression also reduced acid-induced the expression of ASIC1a. In addition, ASIC2a overexpression further promoted the PcTx1 and APETx2-increased levels of type II collagen in acidosis-induced chondrocytes. Taken together, the current data suggested that ASIC2a overexpression might enhance the anti-apoptotic and protective role of PcTx1 and APETx2 against acid-induced rat articular chondrocyte apoptosis by regulating ASIC1a expression and the [Ca2+]i levels and at least in part, suppressing p38 and ERK1/2 MAPK signaling pathways.

Homeobox protein MSX-1 inhibits expression of bone morphogenetic protein 2, bone morphogenetic protein 4, and lymphoid enhancer-binding factor 1 via Wnt/ß-catenin signaling to prevent differentiation of dental mesenchymal cells during the late bell stage.

Homeobox protein MSX-1 (hereafter referred to as MSX-1) is essential for early tooth-germ development. Tooth-germ development is arrested at bud stage in Msx1 knockout mice, which prompted us to study the functions of MSX-1 beyond this stage. Here, we investigated the roles of MSX-1 during late bell stage. Mesenchymal cells of the mandibular first molar were isolated from mice at embryonic day (E)17.5 and cultured in vitro. We determined the expression levels of ß-catenin, bone morphogenetic protein 2 (Bmp2), Bmp4, and lymphoid enhancer-binding factor 1 (Lef1) after knockdown or overexpression of Msx1. Our findings suggest that knockdown of Msx1 promoted expression of Bmp2, Bmp4, and Lef1, resulting in elevated differentiation of odontoblasts, which was rescued by blocking the expression of these genes. In contrast, overexpression of Msx1 decreased the expression of Bmp2, Bmp4, and Lef1, leading to a reduction in odontoblast differentiation. The regulation of Bmp2, Bmp4, and Lef1 by Msx1 was mediated by the Wnt/ß-catenin signaling pathway. Additionally, knockdown of Msx1 impaired cell proliferation and slowed S-phase progression, while overexpression of Msx1 also impaired cell proliferation and prolonged G1-phase progression. We therefore conclude that MSX-1 maintains cell proliferation by regulating transition of cells from G1-phase to S-phase and prevents odontoblast differentiation by inhibiting expression of Bmp2, Bmp4, and Lef1 at the late bell stage via the Wnt/ß-catenin signaling pathway.

Effects of autophagy on acid-sensing ion channel 1a-mediated apoptosis in rat articular chondrocytes.

Rheumatoid arthritis (RA) is a degenerative joint disease that is caused by multiple pathogenic factors. However, the precise etiology of RA is still unknown. Our previous studies demonstrated that acid-sensing ion channel 1a (ASIC1a)-mediated articular chondrocyte apoptosis played a key role in the progression of RA. In this study, we aim to explore whether ASIC1a mediates autophagy or not and the effect of autophagy on ASIC1a-mediated apoptosis. Primary articular chondrocytes, extracted from rat knee joints, were exposed to different concentrations of concentrated hydrochloric acid for different time intervals in vitro. The results indicated that extracellular acid treatment induced autophagy of rat articular chondrocytes. Moreover, inhibition of ASIC1a with either psalmotoxin 1 or ASIC1a short hairpin RNA reduced the autophagy flux. The results suggested that ASIC1a mediated acid-induced autophagy. Pretreatment with autophagy antagonist 3-methyladenine decreased the autophagy, but increased the apoptosis mediated by ASIC1a. Furthermore, knockdown of Beclin 1 by small interfering RNA attenuated autophagy but potentiated ASIC1a-mediated apoptosis of rat articular chondrocytes. Taken together, these findings suggested that both inhibition and silencing of autophagy could enhance ASIC1a-mediated apoptosis in rat articular chondrocytes, and therefore, autophagy is likely to be a new mechanism involved in ASIC1a-mediated apoptosis of articular chondrocytes during the pathogenesis of RA.

Optimization of dispersive liquid-phase microextraction based on solidified floating organic drop combined with high-performance liquid chromatography for the analysis of glucocorticoid residues in food.

A rapid, simple, cost-effective dispersive liquid-phase microextraction based on solidified floating organic drop (SFOD-LPME) was developed in this study. Along with high-performance liquid chromatography, we used the developed approach to determine and enrich trace amounts of four glucocorticoids, namely, prednisone, betamethasone, dexamethasone, and cortisone acetate, in animal-derived food. We also investigated and optimized several important parameters that influenced the extraction efficiency of SFOD-LPME. These parameters include the extractant species, volumes of extraction and dispersant solvents, sodium chloride addition, sample pH, extraction time and temperature, and stirring rate. Under optimum experimental conditions, the calibration graph exhibited linearity over the range of 1.2-200.0ng/ml for the four analytes, with a reasonable linearity(r2: 0.9990-0.9999). The enrichment factor was 142-276, and the detection limits was 0.39-0.46ng/ml (0.078-0.23µg/kg). This method was successfully applied to analyze actual food samples, and good spiked recoveries of over 81.5%-114.3% were obtained.

Functions of interleukin-34 and its emerging association with rheumatoid arthritis.

Rheumatoid arthritis (RA) is a systemic autoimmune disease characterized by chronic, synovial inflammation affecting multiple joints, finally leading to extra-articular lesions for which limited effective treatment options are currently available. Interleukin-34 (IL-34), recently discovered as the second colony-stimulating factor-1 receptor (CSF-1R) ligand, is a newly discovered cytokine. Accumulating evidence has disclosed crucial roles of IL-34 in the proliferation and differentiation of mononuclear phagocyte lineage cells, osteoclastogenesis and inflammation. Recently, IL-34 was detected at high levels in patients with active RA and in experimental models of inflammatory arthritis. Blockade of functional IL-34 with a specific monoclonal antibody can reduce the severity of inflammatory arthritis, suggesting that targeting IL-34 or its receptors may constitute a novel therapeutic strategy for autoimmune diseases such as RA. Here, we have comprehensively discussed the structure and biological functions of IL-34, and reviewed recent advances in our understanding of the emerging role of IL-34 in the development of RA as well as its potential utility as a therapeutic target.

Novel Insights into Acid-Sensing Ion Channels: Implications for Degenerative Diseases.

Degenerative diseases often strike older adults and are characterized by progressive deterioration of cells, eventually leading to tissue and organ degeneration for which limited effective treatment options are currently available. Acid-sensing ion channels (ASICs), a family of extracellular H(+)-activated ligand-gated ion channels, play critical roles in physiological and pathological conditions. Aberrant activation of ASICs is reported to regulate cell apoptosis, differentiation and autophagy. Accumulating evidence has highlighted a dramatic increase and activation of ASICs in degenerative disorders, including multiple sclerosis, Parkinson's disease, Huntington's disease, intervertebral disc degeneration and arthritis. In this review, we have comprehensively discussed the critical roles of ASICs and their potential utility as therapeutic targets in degenerative diseases.

[Comparison of the effect between early anatomical open reduction, internal fixation and closed reduction, internal fixation for treatment of children displaced femoral neck fracture].

OBJECTIVE: To compared the effect between early anatomical open reduction, internal fixation (ORIF) and closed reduction, internal fixation (CRIF) for treatment of children displaced femoral neck fracture. METHODS: From March 2006 to May 2010,34 children with displaced femoral neck fractures were reviewed retrospectively. These patients were divided into two groups. Among them, 19 cases were treated by open reduction and internal fixation (ORIF) as group A, included 11 males and 8 females with an average age of (8.1 +/- 1.3), the other 15 cases were treated by closed reduction and internal fixation (CRIF) as group B, included 9 males and 6 females with an average age of (7.9 +/- 1.5). Complications were observed and the short term effectiveness was evaluated by Ratliff standard. RESULTS: All children were followed-up from 1 to 3 years (means 1.2 years). All fractures were healed. There was statistical different in the curative effects between the two groups (Z=2.389, P= 0.017). The incidence of complications in two groups had statistical different (P=0.046). CONCLUSION: The early ORIF could get better reduction with fewer complications than CRIF in fractures of the displaced femoral neck in children in Delbet type-II and type-III, therefore, ORIF should be considered.

Investigation of anthropometric measurements of anatomic structures of orbital soft tissue in 102 young han chinese adults.

PURPOSE: The aim is to measure and investigate the anatomic structures of orbital soft tissue and the relationships between the adjacent regions in 102 normal young Han Chinese adults using a computer-assisted photography system to provide reference data for periocular cosmetic and reconstructive surgery. METHODS: A random sample of 102 Han young Chinese adults (53 males and 49 females) aged from 18 to 25 years in Changsha, Hunan Province, was obtained. Standard digital images were taken and then processed using Image-Pro Plus 6.0 software. The linear and angular measurements, including intercanthal distance, outer canthal distance, palpebral fissure width (PFW), palpebral fissure height (PFH), orbit height (OH), upper lid height, lower lid height, nasal eyebrow height, central eyebrow height, temporal eyebrow height, reference line to lateral canthus'inclination of palpebral fissure, were measured. The proportional indices, including intercanthal distance/outer canthal distance, PFH/PFW, PFH/OH, OH/PFW, upper lid height/OH, lower lid height/OH, nasal eyebrow height/OH, central eyebrow height/OH, and temporal eyebrow height/OH, were investigated. RESULTS: Means and standard deviations of all the items had been obtained and differences between male and female subjects were assessed. CONCLUSIONS: The normal measurement values of anatomic structures of orbital soft tissue and the proportional indices for normal young Han Chinese adults provided reference data for periorbital cosmetic and reconstructive surgery.

Development of the research on the application of chlorotoxin in imaging diagnostics and targeted therapies for tumors.

Precisely locating tumors always proves to be difficult. To find a molecule that can specifically bind to tumor cells is the key. Recently, chlorotoxin (CTX) has been proved to be able to bind to many kinds of tumor cells. The CTX receptor on the cell surface has been demonstrated to be matrix metalloproteinase-2 (MMP-2). Many researchers have combined CTX with other molecules, including 131I, Cy5.5, iron oxide nanoparticles coated by polyethylene glycol (NP-PEG), and so on, and thus synthesized various types of probes that can be detected by gamma-camera, single photon emission computed tomography (SPECT) or magnetic resonance imaging (MRI). With these methods, the binding degree of CTX could be assessed. These studies demonstrated that CTX has a highly specific binding ability, high stability, and security. CTX could also inhibit or kill the tumor cells. A nonviral nanovector has been developed for gene therapy. As a result, it gradually develops into a new method of diagnosis and targeted therapy of tumors. This article reviews the current progress on CTX including the origin, chemical construction, the mechanism of binding with tumor cells, and the application to tumor imaging diagnosis and therapy.

Anthropometric measurement and analysis of the external nasal soft tissue in 119 young Han Chinese adults.

A random sample of 119 young, healthy Han Chinese adults (56 men and 63 women) between the age of 18 and 25 years (mean, 22.7 y) in PR China was obtained for this study. By the guidance of standard methods, based on Farkas's anthropometric measurements in craniofacial region, 12 nasal soft tissue landmarks and 12 linear and 3 angular measurements were chosen. The linear measurements were taken directly, whereas the angular measurements were taken by photogrammetric method. Eight nasal proportion indices were calculated according to the linear measurements. The application of the independent-samples t-test showed sex dimorphism in most parameters of the nasal region. All the linear measurements were larger in men than in women, whereas all the angular measurements were smaller in men than in women. The significant differences in partial parameters between men and women have been proved. Ten of 12 linear measurements, 1 of 3 angular measurements, and 3 of 8 nasal proportion indices showed significant sexual dimorphism (P < 0.01). Compared with other racial/ethnic groups, the nasal anthropometric measurements and proportion indices of Han Chinese adults were different, to some extent. This study could provide credible and objective reference material for plastic and maxillofacial surgeons for the external nasal soft tissue evaluation and planning of the cosmetic nasal surgery. Besides, these results could be a useful guidance for preoperative and postoperative evaluations of secondary rhinoplasty in nasal deformity associated with cleft lip and palate.

[A case report of sparganosis mansoni in the cheek].

Sparganosis mansoni is a kind of parasitic infective disease, rarely seen in clinic. A case of sparganosis mansoni is reported in this article. The patient was a 25-year-old male, who came to Xiangya Hospital on September 26, 2007 because of a mass in the left cheek. A white tape-like body was found during the operation and recognized to be a live parasite. Enzyme linked immunosorbent assay of the serum revealed positivity against Spirometra mansoni. The final identification proved that the white tape-like body was Sparganum mansoni. The disease of this patient was caused by eating raw flesh of frogs infected with the Sparganum mansoni.