Nucleus pulposus cells degeneration model: a necessary way to study intervertebral disc degeneration.

The availability of an appropriate and reliable research model is helpful for researchers to understand the occurrence and development of diseases. Historically, animal models have been beneficial in the study of intervertebral disc degenerative diseases, but intervertebral disc degeneration (IDD) is a precise and complex process that needs to appear and occur in a specific tissue microenvironment, and animal degeneration models cannot fully simulate these parameters. These challenges must be overcome, especially when animal models cannot fully generalise the complex pathology of humans. In the past few years, the research on the cell disease model has made important progress, and the construction of the nucleus pulposus cell (NPC) degeneration model has become an indispensable step in studying the occurrence and development of IDD. Here, several different methods of constructing NPC degeneration models and indicators for testing the effect of modelling are introduced. The practical applications of cell models constructed by different methods are enumerated to screen and evaluate effective methods of establishing degenerative cell models and explore the mechanism of IDD.

A Scalable and Effective Course Design for Teaching Competency-Based Euthanasia Communication Skills in Veterinary Curricula.

Veterinary staff must be able to navigate end-of-life care with sensitivity and skill to create the best possible outcome for the patient, client, and veterinary team collectively. Despite the clear importance of euthanasia communication and procedural skills in veterinary practice, recent graduates of veterinary programs identified gaps between skills deemed important in clinical practice and skills emphasized in the curriculum. Little time is allocated to euthanasia procedural or communication training across the board in US veterinary programs. Thus, it is of paramount importance to establish intentional and well-designed instruction and assessment of euthanasia communication skills for veterinary trainees. A course on veterinary euthanasia communication skills was designed to emphasize themes and topics essential for a competent veterinarian. Through course evaluations, students expressed the sentiments that this course improved their euthanasia communication skills, that euthanasia communication skills are essential for their careers, and that the course content should be integrated into the core curriculum. This article presents a scaffold for the instruction and assessment of veterinary euthanasia communication skills in alignment with a competency-based veterinary education (CBVE) framework and outlines specific learning interventions used in the course that are scalable and may be extracted and incorporated into existing courses.

Two-dimensional magnetic monopole gas in an oxide heterostructure.

Magnetic monopoles have been proposed as emergent quasiparticles in pyrochlore spin ice compounds. However, unlike semiconductors and two-dimensional electron gases where the charge degree of freedom can be actively controlled by chemical doping, interface modulation, and electrostatic gating, there is as of yet no analogue of these effects for emergent magnetic monopoles. To date, all experimental investigations have been limited to large ensembles comprised of equal numbers of monopoles and antimonopoles in bulk crystals. To address these issues, we propose the formation of a two-dimensional magnetic monopole gas (2DMG) with a net magnetic charge, confined at the interface between a spin ice and an isostructural antiferromagnetic pyrochlore iridate and whose monopole density can be controlled by an external field. Our proposal is based on Monte Carlo simulations of the thermodynamic and transport properties. This proposed 2DMG should enable experiments and devices which can be performed on magnetic monopoles, akin to two-dimensional electron gases in semiconductor heterostructures.

[Clinical randomized controlled trial on influence of recombinant human growth hormone on the immune function of younger children with severe burn injuries].

Objective: To preliminarily investigate the influence of recombinant human growth hormone (rhGH) on the immune function of younger children with severe burn injuries. Methods: A total of 30 younger children with severe burn injuries, conforming to the study criteria, were admitted to our hospital from July 2016 to July 2018. They were enrolled in the prospective, randomized, double-blinded, controlled trial and divided into group rhGH [n=15, 10 boys and 5 girls, aged (22±10) months] and control group [n=15, 8 boys and 7 girls, aged (21±7) months] according to the random number table. The patients in control group received anti-shock, anti-infection, and wound caring therapies, etc. On the basis of above-mentioned treatment, the patients in group rhGH were subcutaneously injected with rhGH once every night before bedding, with a dosage of 0.2 IU·kg(-1)·d(-1), from the 3rd day post injury for 7 consecutive days. Before and on the 3rd and 7th day of rhGH treatments, the fasting peripheral venous blood was collected from patients in both groups. Blood glucose level was detected by glucometer. Percentages of CD4(+) T lymphocytes, CD8(+) T lymphocytes, CD3(+) T lymphocytes, CD19(+) B lymphocytes, and ratio of CD4(+) T lymphocytes to CD8(+) T lymphocytes were determined by flow cytometer. Mass concentration of serum immune globulin (Ig) A, IgG, and complement C3 were detected by enzyme-linked immunosorbent assay. Data were processed with Fisher's exact probability test, independent sample t test, analysis of variance for repeated measurement and Bonferroni correction, and Mann-Whitney U test. Results: (1) The blood glucose levels of children in the two groups were similar before and on the 3rd and 7th day of rhGH treatment (t=0.474, 1.652, 1.997, P>0.05). The glucose levels of children in group rhGH on the 3rd and 7th day of rhGH treatment [(6.9±1.0) and (7.7±1.1) mmol/L] were significantly higher than (5.9±0.9) mmol/L before rhGH treatment (P<0.05). The glucose level of children in control group on the 7th day of rhGH treatment was significantly higher than that before rhGH treatment (P<0.05). (2) The percentages of CD4(+) T lymphocytes of children in group rhGH before rhGH treatment and on the 7th day of rhGH treatment were (35.1±2.0)% and (38.5±2.2)%, which were close to (36.2±2.0)% and (33.6±2.2)% in control group, respectively (t=0.371, 1.553, P>0.05). The percentages of CD4(+) T lymphocytes of children in group rhGH on the 7th day of rhGH treatment[(44.7±2.2)%] was significantly higher than (36.5±2.2)% in control group (t=2.624, P<0.05). The percentage of CD4(+) T lymphocytes of children in group rhGH on the 7th day of rhGH treatment was significantly higher than that before rhGH treatment (P<0.05). The percentages of CD4(+) T lymphocytes of children in control group on the 3rd and 7th day of rhGH treatment were both close to the percentage before rhGH treatment (P>0.05). (3) The percentage of CD8(+) T lymphocytes of children in group rhGH on the 3rd day of rhGH treatment was significantly lower than that in control group (t=2.107, P<0.05). (4) The ratio of CD4(+) T lymphocytes to CD8(+) T lymphocytes of children in group rhGH on the 7th day of rhGH treatment (2.36±0.20) was significantly higher than 1.72±0.20 in control group (t=2.285, P<0.05). The ratio of CD4(+) T lymphocytes to CD8(+) T lymphocytes of children in group rhGH on the 7th day of rhGH treatment was significantly higher than 2.04±0.19 before rhGH treatment (P<0.05). (5) The percentages of CD3(+) T lymphocytes and CD19(+) B lymphocytes of children in the two groups were similar before and on the 3rd and 7th day of rhGH treatment (t=1.913, 0.552, 1.327, 1.465, 1.587, 0.407, P>0.05). The percentages of CD3(+) T lymphocytes of children in group rhGH on the 3rd and 7th day of rhGH treatment were significantly higher than the percentage before rhGH treatment (P<0.05). (6) The mass concentration of serum IgA, complement C3, and IgG of children in the two groups was similar before and on the 3rd and 7th day of rhGH treatment (t=-1.596, -0.100, 1.263, -0.220, 1.378, 1.631, Z=0.228, 0.519, 1.182, P>0.05). The mass concentration of serum IgA and complement C3 of children in group rhGH on the 3rd and 7th day of rhGH treatment was significantly higher than that before rhGH treatment(P<0.05). Conclusions: rhGH has little effect on humoral immunity of younger children with severe burn injuries with limited influence on CD19(+) B lymphocyte, mass concentration of serum IgA, IgG, and complement C3. It may improve the cellular immunity function mainly through promoting the release of CD4(+) T lymphocyte, reducing the release of CD8(+) T lymphocyte. It can be used in clinical treatment of younger children with severe burn injuries.

Observation of room-temperature polar skyrmions.

Complex topological configurations are fertile ground for exploring emergent phenomena and exotic phases in condensed-matter physics. For example, the recent discovery of polarization vortices and their associated complex-phase coexistence and response under applied electric fields in superlattices of (PbTiO3)n/(SrTiO3)n suggests the presence of a complex, multi-dimensional system capable of interesting physical responses, such as chirality, negative capacitance and large piezo-electric responses1-3. Here, by varying epitaxial constraints, we discover room-temperature polar-skyrmion bubbles in a lead titanate layer confined by strontium titanate layers, which are imaged by atomic-resolution scanning transmission electron microscopy. Phase-field modelling and second-principles calculations reveal that the polar-skyrmion bubbles have a skyrmion number of +1, and resonant soft-X-ray diffraction experiments show circular dichroism, confirming chirality. Such nanometre-scale polar-skyrmion bubbles are the electric analogues of magnetic skyrmions, and could contribute to the advancement of ferroelectrics towards functionalities incorporating emergent chirality and electrically controllable negative capacitance.

The efficacy of tranexamic acid for orthognathic surgery: a meta-analysis of randomized controlled trials.

The efficacy of tranexamic acid in orthognathic surgery remains controversial. We conducted a systematic review and meta-analysis to explore the influence of tranexamic acid on blood loss for orthognathic surgery. We performed a search of PubMed, Embase, Web of science, EBSCO, and Cochrane library databases through October 2017 for randomized controlled trials (RCTs) assessing the effects of tranexamic acid versus placebo on orthognathic surgery. Meta-analysis was performed using the random-effects model. Six RCTs were included in the meta-analysis. Overall, compared with placebo in orthognathic surgery, tranexamic acid administration results in significantly decreased blood loss [mean difference (MD)=-159.73; 95% confidence interval (CI)=-236.42 to -83.03; P<0.0001], and higher postoperative haemoglobin (MD=0.71; 95% CI=0.11 to 1.31; P=0.02), but has no remarkable impact on postoperative haematocrit (MD=1.23; 95% CI=-1.22 to 3.69; P=0.33) and operation time (MD=-2.35; 95% CI=-18.05 to 13.36; P=0.77). In addition, patients with orthognathic surgery need decreased amounts of irrigant fluid (MD=-229.23; 95% CI=-399.63 to -58.83; P=0.008) after using tranexamic acid. We concluded that tranexamic acid promotes the bleeding control in orthognathic surgery.

[Meta-analysis on the diagnostic value of laser Doppler imaging for burn depth].

Objective: To evaluate the value of laser Doppler imaging (LDI) in diagnosing deep or superficial partial-thickness burn wound with meta-analysis. Methods: Databases including PubMed, Cochrane Library were searched using key words " burn, burns, burn depth, laser Doppler imaging, laser Doppler perfusion imaging, LDI, LDPI" , and Chinese Journals Full-text Database, Wanfang Database, VIP Database were searched using Chinese key words ",,,," to obtain the published trials of LDI in diagnosing deep or superficial partial-thickness burn wound from the establishment of each database to October 2015. The risk of bias and applicability concerns of the included studies were evaluated by Quality Assessment of Diagnostic Accuracy Studies-2. Data were processed with Meta-DiSc 1.4 statistical software. The heterogeneity among the included studies was evaluated. The pooled estimates of LDI in diagnosing deep or superficial partial-thickness burn wound in the included studies, including sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, as well as the area under the curve of summary receiver operating characteristic and index of Q(*) were calculated. The stability of results of the overall pooled estimates of the included studies was validated by sensitivity analysis. The sources of heterogeneity among the included studies were sought through subgroup analysis. The publication bias caused by the results of the included studies was evaluated by drawing the Deek's funnel plot. Results: A total of 5 articles conforming to the inclusion criteria, involving 138 patients and 179 burn wounds, were included. One of the included studies had low risk of bias, while the other 4 studies had high/unclear risk of bias. In applicability concern aspect, one of the included studies had high/unclear concerns regarding applicability, while the other 4 studies had low concerns regarding applicability. There was no heterogeneity caused by threshold effects among the included studies (no " shoulder arm" plot of the scattered-point distribution was observed in the space of the receiver operating characteristic, ß(s)=0.01, P>0.05). There was a high heterogeneity caused by non-threshold effects among the included studies (sensitivity I(2)=54%). The overall pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio of the included studies on LDI in diagnosing deep or superficial partial-thickness burn wound were 95% (with 95% confidence interval 88%-99%), 96% (with 95% confidence interval 90%-99%), 9.75 (with 95% confidence interval 4.35-21.81), 0.11 (with 95% confidence interval 0.05-0.22), and 257.93 (with 95% confidence interval 58.96-1 128.41), respectively. The area under the curve of summary receiver operating characteristic was 0.98, with index of Q(*) 94%. The results of the overall pooled estimates of the included studies was stable. The risk of bias of the selection of the patients, equipment type of LDI, and the selection of diagnostic method in control might be sources of the heterogeneity of the included studies. The Deek's funnel plot indicated that there was no publication bias caused by the results of the included studies (P>0.05). Conclusions: LDI has high sensitivity, specificity, positive likelihood ratio, diagnostic odds ratio and index of Q(*,) large area under the curve of summary receiver operating characteristics, and low negative likelihood ratio in diagnosing deep or superficial partial-thickness burn wound, which has relatively high diagnostic value.

Top-down approach from satellite to terrestrial rover application for environmental monitoring of landfills.

This paper describes a methodology to perform chemical analyses in landfill areas by integrating multisource geomatic data. We used a top-down approach to identify Environmental Point of Interest (EPI) based on very high-resolution satellite data (Pleiades and WorldView 2) and on in situ thermal and photogrammetric surveys. Change detection techniques and geostatistical analysis supported the chemical survey, undertaken using an accumulation chamber and an RIIA, an unmanned ground vehicle developed by CNR IIA, equipped with a multiparameter sensor platform for environmental monitoring. Such an approach improves site characterization, identifying the key environmental points of interest where it is necessary to perform detailed chemical analyses.

[Construction and preliminary applications of a Saccharomyces cerevisiae detection plasmid using for screening promoter elements].

Synthetic biology of natural products is the design and construction of new biological systems by transferring a metabolic pathway of interest products into a chassis. Large-scale production of natural products is achieved by coordinate expression of multiple genes involved in genetic pathway of desired products. Promoters are cis-elements and play important roles in the balance of the metabolic pathways controlled by multiple genes by regulating gene expression. A detection plasmid of Saccharomyces cerevisiae was constructed based on DsRed-Monomer gene encoding for a red fluorescent protein. This plasmid was used for screening the efficient promoters applying for multiple gene-controlled pathways. First of all, eight pairs of primers specific to DsRed-Monomer gene were synthesized. The rapid cloning of DsRed-Monomer gene was performed based on step-by-step extension of a short region of the gene through a series of PCR reactions. All cloned sequences were confirmed by DNA sequencing. A vector named pEASYDs-M containing full-length DsRed-Monomer gene was constructed and was used as the template for the construction of S. cerevisiae expression vector named for pYeDP60-Ds-M. pYeDP60-Ds-M was then transformed into S. cerevisiae for heterologous expression of DsRed-Monomer gene. SDS-PAGE, Western blot and fluorescence microscopy results showed that the recombinant DsRed-Monomer protein was expressed successfully in S. cerevisiae. The well-characterized DsRed-Monomer gene was then cloned into a yeast expression vector pGBT9 to obtain a promoter detection plasmid pGBT9Red. For determination efficacy of pGBT9Red, six promoters (including four inducible promoters and two constitutive promoters) were cloned by PCR from the S. cerevisiae genome, and cloned into pGBT9Red by placing upstream of DsRed-Monomer gene, separately. The fluorescence microscopy results indicated that the six promoters (GAL1, GAL2, GAL7, GAL10, TEF2 and PGK1) can regulate the expression of DsRed-Monomer gene. The successful construction of pGBT9Red lays the foundation for further analysis of promoter activity and screening of promoter element libraries.

Two novel mutations of the NCSTN gene in Chinese familial acne inverse.

BACKGROUND: Acne inversa (AI; MIM 142690), or hidradenitis suppurativa (HS), is a type of autosomal-dominant genodermatosis caused by mutations in γ-secretase. The complex of γ-secretase is a transmembrane protease that catalyses the cleavage of a set of membrane proteins and is comprised of four subunits encoded by four genes, including PSEN1, PSENEN, NCSTN and APH1. However, mutations associated with AI vary significantly, and it is important to define the specific mutation with a particular AI patient. OBJECTIVE: To determine specific mutations in the γ-secretase gene associated with two Chinese AI families. METHODS: Two families of three generations with apparent AI symptoms were examined through proband analysis. Genomic DNAs of the family members and a cohort of 100 healthy individuals were isolated and subjected to polymerase chain reaction (PCR) and direct DNA sequencing. RESULTS: Two heterozygous missense mutations, c.647A>C (p.Q216P) in the exon 6, and c.223G>A (p.V75I) in the exon 3 of the NCSTN gene, were identified in the two families respectively. No mutations were found in 100 healthy individuals. CONCLUSIONS: We have identified two novel mutations within the NCSTN gene associated with AI.

Lysine 63-linked ubiquitination modulates mixed lineage kinase-3 interaction with JIP1 scaffold protein in cytokine-induced pancreatic ß cell death.

The mixed lineage kinase MLK3 plays a crucial role in compromising mitochondrial integrity and functions as a proapoptotic competence factor in the early stages of cytokine-induced pancreatic ß cell death. In an effort to identify mechanisms that regulate MLK3 activity in ß cells, we discovered that IL-1ß stimulates Lys-63-linked ubiquitination of MLK3 via a conserved, TRAF6-binding peptapeptide motif in the catalytic domain of the kinase. TRAF6-mediated ubiquitination was required for dissociation of inactive monomeric MLK3 from the scaffold protein IB1/JIP1, facilitating the subsequent dimerization, autophosphorylation, and catalytic activation of MLK3. Inability to ubiquitinate MLK3, or the presence of A20, an upstream Lys-63-linked deubiquitinase, strongly curtailed the ability of MLK3 to affect the proapoptotic translocation of BAX in cytokine-stimulated pancreatic ß cells, an early step in the progression toward ß cell death. These studies suggest a novel mechanism for MLK3 activation and provide new clues for therapeutic intervention in promoting ß cell survival.

Mixed lineage kinase-3 stabilizes and functionally cooperates with TRIBBLES-3 to compromise mitochondrial integrity in cytokine-induced death of pancreatic beta cells.

Mixed lineage kinases (MLKs) have been implicated in cytokine signaling as well as in cell death pathways. Our studies show that MLK3 is activated in leukocyte-infiltrated islets of non-obese diabetic mice and that MLK3 activation compromises mitochondrial integrity and induces apoptosis of beta cells. Using an ex vivo model of islet-splenocyte co-culture, we show that MLK3 mediates its effects via the pseudokinase TRB3, a mammalian homolog of Drosophila Tribbles. TRB3 expression strongly coincided with conformational change and mitochondrial translocation of BAX. Mechanistically, MLK3 directly interacted with and stabilized TRB3, resulting in inhibition of Akt, a strong suppressor of BAX translocation and mitochondrial membrane permeabilization. Accordingly, attenuation of MLK3 or TRB3 expression each prevented cytokine-induced BAX conformational change and attenuated the progression to apoptosis. We conclude that MLKs compromise mitochondrial integrity and suppress cellular survival mechanisms via TRB3-dependent inhibition of Akt.

Past environmental sun exposure and risk of multiple sclerosis: a role for the Cdx-2 Vitamin D receptor variant in this interaction.

Multiple studies have provided evidence for an association between reduced sun exposure and increased risk of multiple sclerosis (MS), an association likely to be mediated, at least in part, by the vitamin D hormonal pathway. Herein, we examine whether the vitamin D receptor (VDR), an integral component of this pathway, influences MS risk in a population-based sample where winter sun exposure in early childhood has been found to be an important determinant of MS risk. Three polymorphisms within the VDR gene were genotyped in 136 MS cases and 235 controls, and associations with MS and past sun exposure were examined by logistic regression. No significant univariate associations between the polymorphisms, rs11574010 (Cdx-2A > G), rs10735810 (Fok1T > C), or rs731236 (Taq1C > T) and MS risk were observed. However, a significant interaction was observed between winter sun exposure during childhood, genotype at rs11574010, and MS risk (P = 0.012), with the 'G' allele conferring an increased risk of MS in the low sun exposure group (

Grb10: more than a simple adaptor protein.

Grb10 is a member of a superfamily of adaptor proteins that includes Grb7 and Grb14. This family of proteins shares a common overall structure, including an N-terminal region harboring a conserved proline-rich motif, a central Pleckstrin homology (PH) domain, a C-terminal Src homology 2 (SH2) domain, and a conserved region located between the PH and the SH2 domains (BPS). Grb10 directly interacts with a number of mitogenic receptor tyrosine kinases including the insulin (IR) and insulin-like growth factor-I (IGF-IR) receptor. Grb10 binds to the regulatory kinase loop of the insulin receptor (IR) via its SH2 and BPS domains. In addition to receptor tyrosine kinases, Grb10 has also been found to interact with non-receptor tyrosine kinases such as Tec and Bcr-Abl, and other cellular signaling molecules such as Raf-1 and the mitogen activated protein (MAP) kinase kinase, MEK. Overexpression of Grb10 has been shown to inhibit or stimulate insulin/IGF-I signaling depending on the expression levels of the specific isoforms, specific cell context, and/or physiologic endpoint. Genetic imprinting of Grb10 has been linked to the congenital disease, Silver-Russell syndrome, which is characterized by pre- and post-natal growth deficiency. This data suggests that Grb10 may function during embryogenesis in regulating insulin/IGF-I signaling as these growth factors play important roles during development. A role of Grb10 as a potent growth inhibitor during was implicated when disruption of the mGrb10 gene in mice resulted in overgrowth of mutant embryos and neonates. Grb10 is expressed in the central nervous system of mice and rats, which suggests that this protein may regulate neuronal insulin signaling and energy metabolism, consistent with its reported role in metabolic insulin action in fat and muscle cells. An important area of future investigation will be to elucidate the mechanism underlying Grb10's ability to regulate peptide hormone action including insulin/IGF-I signaling and to study the physiological role of this adaptor protein in cellular and animal models.

Nuclear translocation of 3'-phosphoinositide-dependent protein kinase 1 (PDK-1): a potential regulatory mechanism for PDK-1 function.

3'-Phosphoinositide-dependent protein kinase 1 (PDK-1) phosphorylates and activates members of the AGC protein kinase family and plays an important role in the regulation of cell survival, differentiation, and proliferation. However, how PDK-1 is regulated in cells remains elusive. In this study, we demonstrated that PDK-1 can shuttle between the cytoplasm and nucleus. Treatment of cells with leptomycin B, a nuclear export inhibitor, results in a nuclear accumulation of PDK-1. PDK-1 nuclear localization is increased by insulin, and this process is inhibited by pretreatment of cells with phosphatidylinositol 3-kinase (PI3-kinase) inhibitors. Consistent with the idea that PDK-1 nuclear translocation is regulated by the PI3-kinase signaling pathway, PDK-1 nuclear localization is increased in cells deficient of PTEN (phosphatase and tensin homologue deleted on chromosome 10). Deletion mapping and mutagenesis studies unveiled that presence of a functional nuclear export signal (NES) in mouse PDK-1 located at amino acid residues 382 to 391. Overexpression of constitutively nuclear PDK-1, which retained autophosphorylation at Ser-244 in the activation loop in cells and its kinase activity in vitro, led to increased phosphorylation of the predominantly nuclear PDK-1 substrate p70 S6KbetaI. However, the ability of constitutively nuclear PDK-1 to induce anchorage-independent growth and to protect against UV-induced apoptosis is greatly diminished compared with the wild-type enzyme. Taken together, these findings suggest that nuclear translocation may be a mechanism to sequestrate PDK-1 from activation of the cytosolic signaling pathways and that this process may play an important role in regulating PDK-1-mediated cell signaling and function.