Small clinical trials have reported that low-frequency repetitive transcranial magnetic stimulation (rTMS) might improve language recovery in patients with aphasia after stroke. However, no systematic reviews or meta-analyses studies have investigated the effect of rTMS on aphasia. The objective of this study was to perform a meta-analysis of studies that explored the effects of low-frequency rTMS on aphasia in stroke patients.
We searched PubMed, CENTRAL, Embase, CINAHL, ScienceDirect, and Journals@Ovid for randomized controlled trials published between January 1965 and October 2013 using the keywords “aphasia OR language disorders OR anomia OR linguistic disorders AND repetitive transcranial magnetic stimulation OR rTMS”. We used fixed- and random-effects models to estimate the standardized mean difference (SMD) and a 95% CI for the language outcomes.
Seven eligible studies involving 160 stroke patients were identified in this meta-analysis. A significant effect size of 1.26 was found for the language outcome severity of impairment (95% CI = 0.80 to 1.71) without heterogeneity (I2 = 0%, P = 0.44). Further analyses demonstrated prominent effects for the naming subtest (SMD = 0.52, 95% CI = 0.18 to 0.87), repetition (SMD = 0.54, 95% CI = 0.16 to 0.92), writing (SMD = 0.70, 95% CI = 0.19 to 1.22), and comprehension (the Token test: SMD = 0.58, 95% CI = 0.07 to 1.09) without heterogeneity (I2 = 0%). The SMD of AAT and BDAE comprehension subtests was 0.32 (95% CI = −0.08 to 0.72) with moderate heterogeneity (I2 = 32%,P = 0.22). The effect size did not change significantly even when any one trial was eliminated. None of the patients from the 7 included articles reported adverse effects from rTMS.
Low-frequency rTMS with a 90% resting motor threshold that targets the triangular part of the right inferior frontal gyrus (IFG) has a positive effect on language recovery in patients with aphasia following stroke. Further well-designed studies with larger populations are required to ascertain the long-term effects of rTMS in aphasia treatment.
Adaptive responses can be induced in cells by very low doses of ionizing radiation resulting in an enhanced resistance to much larger exposures. The inhibitor of apoptosis (IAP) protein, survivin, has been implicated in many adaptive responses to cellular stress. Computerized axial tomography (CAT) used in image guided radiotherapy to position and monitor tumor response utilizes very low radiation doses ranging from 0.5 to 100 mGy. We investigated the ability of these very low radiation doses administered along with two 2 Gy doses separated by 24 h, a standard conventional radiotherapy dosing schedule, to initiate adaptive responses resulting in the elevation of radiation resistance in exposed cells. Human colon carcinoma (RKO36), mouse sarcoma (SA-NH), along with transformed mouse embryo fibroblasts (MEF), wild type (WT) or cells lacking functional tumor necrosis factor receptors 1 and 2 (TNFR1−R2−) were used to assess their relative ability to express an adaptive response when grown either to confluence in vitro or as tumors in the flank of C57BL/6 mice. The survival of each of these cells was elevated from 5 to 20% (P ≤ 0.05) as compared to cells not receiving a 100 mGy or lesser dose. Additionally, the cells exposed to 100 mGy exhibited elevations in survivin levels, reductions in apoptosis frequencies, and loss of an adaptive response if transfected with survivin siRNA. This survivin-mediated adaptive response has the potential for affecting outcomes if regularly induced throughout a course of image guided radiation therapy.
Adaptive-response; Survivin; Computed Tomography; TNF receptors
Osteosarcoma is the most common primary tumor of the bone. It leads to many deaths because of its rapid proliferation and metastasis. Recent studies have shown that microRNAs are important gene regulators that are involved in various cancer-related processes. In this study, we found that miR-135b was down-regulated in both osteoscarcoma patient tumor tissues and osteoscarcoma cell lines in comparison to paired adjacent non-tumor bone tissue. We observed that a lower level of miR-135b was associated with metastasis. The ectopic expression of miR-135b markedly suppressed osteoscarcoma cell proliferation, migration, and invasion. Conversely, the inhibition of miR-135b expression dramatically accelerated cell proliferation, migration, and invasion. The forced expression of miR-135b in osteosarcoma cells resulted in a significant reduction in the protein level of c-Myc and repressed the activity of a luciferase reporter that contained the 3′-untranslated region of the c-Myc mRNA. These effects were abolished by the mutation of the predicted miR-135b-binding site, which indicates that c-Myc may be a miR-135b target gene. Moreover, the ectopic expression of c-Myc partially reversed the inhibition of cell proliferation and invasion that was caused by miR-135b. These data therefore suggest that miR-135b may function as a tumor suppressor to regulate osteosarcoma cell proliferation and invasion through a mechanism that targets the c-Myc oncogene. These findings indicate that miR-135b may play a role in the pathogenesis of osteosarcoma.
We propose an automated algorithm for classifying diagnostic categories of otitis media (middle ear inflammation); acute otitis media, otitis media with effusion and no effusion. Acute otitis media represents a bacterial superinfection of the middle ear fluid and otitis media with effusion a sterile effusion that tends to subside spontaneously. Diagnosing children with acute otitis media is hard, leading to overprescription of antibiotics that are beneficial only for children with acute otitis media, prompting a need for an accurate and automated algorithm. To that end, we design a feature set understood by both otoscopists and engineers based on the actual visual cues used by otoscopists; we term this otitis media vocabulary. We also design a process to combine the vocabulary terms based on the decision process used by otoscopists; we term this otitis media grammar. The algorithm achieves 84% classification accuracy, in the range or outperforming clinicians who did not receive special training, as well as state-of-the-art classifiers.
otitis media; classification; vocabulary; grammar
Human pancreatic islet transplantation is a prospective curative treatment for diabetes. However, the lack of donor pancreases greatly limits this approach. One approach to overcome the limited supply of donor pancreases is to generate functional islets from human embryonic stem cells (hESCs), a cell line with unlimited proliferative capacity, through rapid directed differentiation. This study investigated whether pancreatic insulin-producing cells (IPCs) differentiated from hESCs could correct hyperglycemia in severe combined immunodeficient (SCID)/non-obese diabetic (NOD) mice, an animal model of diabetes.
We generated pancreatic IPCs from two hESC lines, YT1 and YT2, using an optimized four-stage differentiation protocol in a chemically defined culture system. Then, about 5–7×106 differentiated cells were transplanted into the epididymal fat pad of SCID/NOD mice (n = 20). The control group were transplanted with undifferentiated hESCs (n = 6). Graft survival and function were assessed using immunohistochemistry, and measuring serum human C-peptide and blood glucose levels.
The pancreatic IPCs were generated by the four-stage differentiation protocol using hESCs. About 17.1% of differentiated cells expressed insulin, as determined by flow cytometry. These cells secreted insulin/C-peptide following glucose stimulation, similarly to adult human islets. Most of these IPCs co-expressed mature β cell-specific markers, including human C-peptide, GLUT2, PDX1, insulin, and glucagon. After implantation into the epididymal fat pad of SCID/NOD mice, the hESC-derived pancreatic IPCs corrected hyperglycemia for ≥8 weeks. None of the animals transplanted with pancreatic IPCs developed tumors during the time. The mean survival of recipients was increased by implanted IPCs as compared to implanted undifferentiated hESCs (P<0.0001).
The results of this study confirmed that human terminally differentiated pancreatic IPCs derived from hESCs can correct hyperglycemia in SCID/NOD mice for ≥8 weeks.
Nutrient availability greatly regulates ecosystem processes and functions of tropical forests. However, few studies have explored impacts of N addition (aN), P addition (aP) and N×P interaction on tropical forests N2O fluxes. We established an N and P addition experiment in a tropical forest to test whether: (1) N addition would increase N2O emission and nitrification, and (2) P addition would increase N2O emission and N transformations. Nitrogen and P addition had no effect on N mineralization and nitrification. Soil microbial biomass was increased following P addition in wet seasons. aN increased 39% N2O emission as compared to control (43.3 μgN2O-N m−2h−1). aP did not increase N2O emission. Overall, N2O emission was 60% greater for aNP relative to the control, but significant difference was observed only in wet seasons, when N2O emission was 78% greater for aNP relative to the control. Our results suggested that increasing N deposition will enhance soil N2O emission, and there would be N×P interaction on N2O emission in wet seasons. Given elevated N deposition in future, P addition in this tropical soil will stimulate soil microbial activities in wet seasons, which will further enhance soil N2O emission.
AIM: To investigate the effect of Girdin knockdown on the chemosensitivity of colorectal cancer cells to oxaliplatin and the possible mechanisms involved.
METHODS: Four siRNAs targeting Girdin were transfected into the chemoresistant colorectal cancer cell line DLD1. Real-time polymerase chain reaction (PCR) was employed to assess Girdin mRNA expression and the most effective siRNA was chosen for conversion into shRNA. Then, DLD1 cells were infected with lentiviruses expressing the Girdin shRNA and a scramble control, respectively, and Girdin mRNA and protein expression levels were assessed by real-time PCR and Western blotting. Furthermore, microarray experiments were used to assess global gene expression profile after Girdin suppression in DLD1 cells. Finally, the cytotoxic effect of simultaneous treatment with oxaliplatin and adriamycin (an inhibitor of a significantly downregulated gene after Girdin suppression in DLD1 cells) was examined by MTT assay.
RESULTS: The most effective siRNA suppressed Girdin expression with an inhibition efficiency of 57%. Compared with the scramble control, DLD1 cells infected with the Girdin shRNA displayed decreased Girdin mRNA and protein levels (P < 0.05), and Girdin knockdown significantly enhanced chemosensitivity to oxaliplatin in colorectal cancer cells (P < 0.05). Microarray data revealed that 381 and 162 genes were upregulated and downregulated in response to Girdin reduction, respectively, with ratios > 1.2 or < 0.8 (P < 0.01). Interestingly, TOP2B (DNA topoisomerase 2-β) was downregulated (ratio = 0.78, P = 0.0001) and oxaliplatin/adriamycin combination resulted in increased cell death compared with treatments with individual agents (P < 0.05).
CONCLUSION: Girdin knockdown enhances chemosensitivity of colorectal cancer cells to oxaliplatin via TOP2B down-regulation. These findings provide a promising approach to overcome the chemoresistance of colorectal cancer cells.
Oxaliplatin; Chemosensitivity; Girdin; Colorectal cancer; TOP2B
Glycated hemoglobin (HbA1c) predicts clinical cardiovascular disease or cardiovascular mortality. However, the relationship between HbA1c and myocardial injury following elective percutaneous coronary intervention (PCI) in patients with type 2 diabetes mellitus (DM) has not been investigated.
The study sought to assess the relationship between HbA1c and myocardial injury following elective PCI in patients with type 2 DM.
We studied a cohort of consecutive 994 diabetic patients with coronary artery disease (CAD) undergoing elective PCI. Periprocedural myocardial injury was evaluated by analysis of troponin I (cTnI). The association between preprocedural HbA1c levels and the peak values of cTnI within 24 hours after PCI was evaluated.
Peak postprocedural cTnI >1×upper limit of normal (ULN), >3×ULN and >5×ULN were detected in 543 (54.6%), 337 (33.9%) and 245 (24.6%) respectively. In the multivariate model, higher HbA1c levels were associated with less risk of postprocedural cTnI >1×ULN (odds ratio [OR], 0.85; 95% confidence interval [CI], 0.76–0.95; P = 0.005). There was a trend that higher HbA1c levels were associated with less risk of postprocedural cTnI >3×ULN (OR, 0.90; 95% CI, 0.81–1.02; P = 0.088). HbA1c was not associated with the risk of postprocedural cTnI elevation above 5×ULN (OR, 0.95; 95% CI, 0.84–1.08; P = 0.411).
The present study provided the first line of evidence that higher preprocedural HbA1c levels were associated with less risk of myocardial injury following elective PCI in diabetic patients.
The spinal cord is composed of distinct neuronal groups with well-defined anatomic connections. In some transgenic models of Alzheimer’s disease (AD) amyloid plaques develop in this structure, although the underlying cellular mechanism remains elusive. We attempted to explore the origin, evolution and modulation of spinal β-amyloid (Aβ) deposition using transgenic mice harboring five familiar AD-related mutations (5XFAD) as an experiential model. Dystrophic neuritic elements with enhanced β-secretase-1 (BACE1) immunoreactivity (IR) appeared as early as 2 months of age, and increased with age up to 12 months examined in this study, mostly over the ventral horn (VH). Extracellular Aβ IR emerged and developed during this same period, site-specifically co-existing with BACE1-labeled neurites often in the vicinity of large VH neurons that expressed the mutant human APP. The BACE1-labled neurites almost invariably colocalized with β-amyloid precursor protein (APP) and synaptophysin, and frequently with the vesicular glutamate transporter-1 (VGLUT). Reduced IR for the neuronal specific nuclear antigen (NeuN) occurred in the VH by 12 months of age. In 8 month-old animals surviving 6 months after an unilateral sciatic nerve transection, there were significant increases of Aβ, BACE1 and VGLUT IR in the VN of the ipsilateral relative to contralateral lumbar spinal segments. These results suggest that extracellular Aβ deposition in 5XFAD mouse spinal cord relates to a progressive and amyloidogenic synaptic pathology largely involving presynaptic axon terminals from projection neurons in the brain. Spinal neuritic plaque formation is enhanced after peripheral axotomy, suggesting a retrograde transneuronal modulation on pathogenesis.
Alzheimer’s disease; amyloidogenesis; BACE1; neuritic dystrophy; synaptoplasticity
Colistin, administered intravenously as its inactive prodrug colistin methanesulfonate (CMS), is increasingly used as last-line therapy to combat multidrug-resistant Gram-negative bacteria. CMS dosing needs to be adjusted for renal function. The impact of continuous ambulatory peritoneal dialysis (CAPD) on the pharmacokinetics of both CMS and colistin has not been studied. No CMS dosing recommendations are available for patients receiving CAPD. Eight CAPD patients received a single intravenous CMS dose (150 mg colistin base activity [CBA]) over 30 min. Serial blood and dialysate samples, and cumulative urine where applicable, were collected over 25 h. CMS and colistin concentrations were determined by high-performance liquid chromatography. Population pharmacokinetic modeling and Monte Carlo simulations were conducted. The total body clearance of CMS (excluding CAPD clearance) was 1.77 liters/h (44%) [population mean (between-subject variability)], while CAPD clearance was 0.088 liter/h (64%). The population mean terminal half-life of CMS was 8.4 h. For colistin, the total clearance/fraction of CMS metabolized to colistin (fm) (excluding CAPD clearance) was 2.74 liters/h (50%), the CAPD clearance was 0.101 liter/h (34%), and the mean terminal half-life was 13.2 h. Monte Carlo simulations suggested a loading dose of 300 mg CBA on day 1 and a maintenance dose of either 150 mg or 200 mg CBA daily to achieve a target average steady-state plasma colistin concentration of 2.5 mg/liter. Clearance by CAPD was low for both CMS and formed colistin. Therefore, CMS doses should not be increased during CAPD. Modeling and simulation enabled us to propose the first evidence-based CMS dosage regimen for CAPD patients.
Though the compromised blood-brain barrier (BBB) is a pathological hallmark of Japanese encephalitis-associated neurological sequelae, the underlying mechanisms and the specific cell types involved are not understood. BBB characteristics are induced and maintained by cross talk between brain microvascular endothelial cells and neighboring elements of the neurovascular unit. In this study, we show a potential mechanism of disruption of endothelial barrier integrity during the course of Japanese encephalitis virus (JEV) infection through the activation of neighboring pericytes. We found that cultured brain pericytes were susceptible to JEV infection but were without signs of remarkable cytotoxicity. JEV-infected pericytes were found to release biologically active molecules which activated ubiquitin proteasome, degraded zonula occludens-1 (ZO-1), and disrupted endothelial barrier integrity in cultured brain microvascular endothelial cells. Infection of pericytes with JEV was found to elicit elevated production of interleukin-6 (IL-6), which contributed to the aforementioned endothelial changes. We further demonstrated that ubiquitin-protein ligase E3 component n-recognin-1 (Ubr 1) was a key upstream regulator which caused proteasomal degradation of ZO-1 downstream of IL-6 signaling. During JEV central nervous system trafficking, endothelial cells rather than pericytes are directly exposed to cell-free viruses in the peripheral bloodstream. Therefore, the results of this study suggest that subsequent to primary infection of endothelial cells, JEV infection of pericytes might contribute to the initiation and/or augmentation of Japanese encephalitis-associated BBB breakdown in concerted action with other unidentified barrier disrupting factors.
During liquid-phase synthesis of γ-Fe2O3 nanoparticles by chemically induced transition in FeCl2 solution, enhancement of surface modification by adding ZnCl2 was attempted by using NaOH. By using transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, energy-dispersive X-ray spectrometry, and vibrating sample magnetometry, the dependence of the synthesis on the amount of additional NaOH was studied.
The experimental results show that the surface of the γ-Fe2O3 nanoparticles could be modified by adding ZnCl2 to form composite nanoparticles with γ-Fe2O3/ZnFe2O4 ferrite core coated with Zn(OH)2 and adsorbed FeCl3, and that modification could be enhanced by adding NaOH.
In the experimental conditions, when the concentration of additional NaOH was below 0.70 M, the amounts of ZnFe2O4 and Zn(OH)2 phases increased slightly and that of adsorbed FeCl3 was unchanged. When the concentration of NaOH exceeded 0.70 M, the amount of FeCl3, ZnFe2O4, and Zn(OH)2 increased.
Nanoparticles; Composite; Surface modification; γ-Fe2O3; ZnFe2O4
The aim of this study was to investigate the effects of 131I gelatin microspheres (131I-GMS) on human breast cancer cells (MCF-7) in nude mice and the biodistribution of 131I-GMSs following intratumoral injections.
A total of 20 tumor-bearing mice were divided into a treatment group and control group and received intratumoral injections of 2.5 mci 131I-GMSs and nonradioactive GMSs, respectively. Tumor size was measured once per week. Another 16 mice received intratumoral injections of 0.4 mci 131I-GMSs and were subjected to single photon emission computed tomography (SPECT) scans and tissue radioactivity concentration measurements on day 1, 4, 8 and 16 postinjection. The 20 tumor-bearing mice received intratumoral injections of 0.4 mci [131I] sodium iodide solution and were subjected to SPECT scans and intratumoral radioactivity measurements at 1, 6, 24, 48 and 72 h postinjection. The tumors were collected for histological examination.
The average tumor volume in the 131I-GMSs group on post-treatment day 21 decreased to 86.82 ± 63.6%, while it increased to 893.37 ± 158.12% in the control group (P < 0.01 vs. the 131I-GMSs group). 131I-GMSs provided much higher intratumoral retention of radioactivity, resulting in 19.93 ± 5.24% of the injected radioactivity after 16 days, whereas the control group retained only 1.83 ± 0.46% of the injected radioactivity within the tumors at 1 h postinjection.
131I-GMSs suppressed the growth of MCF-7 in nude mice and provided sustained intratumoral radioactivity retention. The results suggest the potential of 131I-GMSs for clinical applications in radiotherapy for breast cancer.
131I; Gelatin microspheres; Breast neoplasms; Intratumoral injection; Treatment outcome; Biodistribution
Chronic administration of cocaine attenuates delta opioid receptor (DOPR) signaling in the striatum and the desensitization is mediated by the indirect actions of cocaine on dopamine D1 receptors (D1R). In addition, DOPR and D1R co-exist in some rat striatal neurons. In the present study, we examined the underlying mechanism of DOPR desensitization by D1R activation.
NG 108-15 cells stably expressing HA-rat D1 receptor (HA-D1R) and Chinese hamster ovary (CHO) cells stably expressing both FLAG-mouse DOPR (FLAG-DOPR) and HA-D1R were used as the cell models. Receptor binding, [35S]GTPγS binding, receptor phosphorylation and western blot were conducted to examine DOPR affinity, expression, internalization, downregulation, desensitization, phosphorylation and phosphorylated ERK1/2.
Pretreatment with either the DOPR agonist DPDPE or the D1R agonist SKF-82958 for 30 min attenuated DPDPE-stimulated [35S]GTPγS binding to G proteins, demonstrating homologous and heterologous desensitization of the DOPR, respectively. SKF-82958 pretreatment did not affect the level of DOPR or affinity of DOPR antagonist or agonists, nor did it induce phosphorylation, internalization or down-regulation of the DOPR in the CHO-FLAG-DOPR/HA-D1R cells. Pretreatment of cells with inhibitors of PKA, MEK1 and PI3K, but not PKC, attenuated SKF-82958-induced desensitization of the DOPR. The D1R agonist SKF-82958 enhanced phosphorylation of ERK1/2, and pretreatment with inhibitors of MEK1 and PI3K, but not PKA and PKC reduced the effect. These results indicate that activation of ERK1/2 and/or PKA, but not PKC, is involved in D1 receptor-induced heterologous desensitization of the DOPR.
This study provides possible mechanisms underlying D1R activation-induced DOPR desensitization.
Heterologous desensitization; delta opioid receptor; dopamine D1 receptor; PKA; ERK1/2
Tangzhiqing fomula (TZQ-F), the mixture of Red Paeony root, Mulberry leaf, Lotus leaf, Danshen root and Hawthorn leaf, regulates the abnormal glucose and lipids in prediabetic patients. In this study, we focus on the mechanism of TZQ-F and its fractions on glucose metabolism.
After orally administration of TZQ-F for 4 weeks in KK-Ay mice, we dissected out the liver and muscle, and employed PCR and western blotting to screening the PI3K/AKT pathway. The following PI3K/AKT signaling pathway were performed in L-6 myotube and HepG2 cells.
In the liver of KK-Ay mice, no significance was observed on PI3K, AKT and their phosphorylation between TZQ-F and controls , while, in the muscle, up-regulation of PI3K, AKT, Glycogen synthase (GYS) and their phosphorylation type, as well as GluT4, was deteced in TZQ-F. In HepG2 cells, TZQ-F increased IRS-2 by 10 folds, without interrupting AKT, IRS-1 and GluT4. In L-6 myotube cells, TZQ-F and its fractions treatment significantly increased IRS-1 and AKT at mRNA level.
TZQ-F prevents pre-diabetes through increasing effect on IRS-1-dependent PI3K/AKT signaling pathway in muscle.
IRS-1-dependent PI3K signaling pathway; Insulin resistance; Paeonia lactiflora; Morus alba; Nelumbo nucifera; Salvia miltiorrhiza; Crataegus pinnatifida
Shuang-huang-lian injection (SHLI) is a famous Chinese patent medicine, which has been wildly used in clinic for the treatment of acute respiratory tract infection, pneumonia, influenza, etc. The existing randomized controlled trial (RCT) studies suggested that SHLI could afford a certain anti-febrile action. However, seldom does research concern the pharmacological mechanisms of SHLI. In the current study, we explored plasma metabolomic profiling technique and selected potential metabolic markers to reveal the antipyretic mechanism of SHLI on yeast-induced pyrexia rat model using UPLC-Q-TOF/MS coupled with multivariate statistical analysis and pattern recognition techniques. We discovered a significant perturbance of metabolic profile in the plasma of fever rats and obvious reversion in SHLI-administered rats. Eight potential biomarkers, i.e. 1) 3-hydeoxybutyric acid, 2) leucine, 3) 16∶0 LPC, 4) allocholic acid, 5) vitamin B2, 6) Cys-Lys-His, 7) 18∶2 LPC, and 8) 3-hydroxychola-7, 22-dien-24-oic acid, were screened out by OPLS-DA approach. Five potential perturbed metabolic pathways, i.e. 1) valine, leucine, and isoleucine biosynthesis, 2) glycerophospholipid metabolism, 3) ketone bodies synthesis and degradation, 4) bile acid biosynthesis, and 5) riboflavin metabolism, were revealed to relate to the antipyretic mechanisms of SHLI. Overall, we investigated antipyretic mechanisms of SHLI at metabolomic level for the first time, and the obtained results highlights the necessity of adopting metabolomics as a reliable tool for understanding the holism and synergism of Chinese patent drug.
The shortage of physicians is an evolving problem throughout the world. In this study we aimed to identify to what extent junior doctors’ training and working conditions determine their intention to leave clinical practice after residency training.
A prospective cohort study was conducted in 557 junior doctors undergoing residency training in German hospitals. Self-reported specialty training conditions, working conditions and intention to leave clinical practice were measured over three time points. Scales covering training conditions were assessed by structured residency training, professional support, and dealing with lack of knowledge; working conditions were evaluated by work overload, job autonomy and social support, based on the Demand–Control–Support model. Multivariate ordinal logistic regression analyses with random intercept for longitudinal data were applied to determine the odds ratio of having a higher level of intention to leave clinical practice.
In the models that considered training and working conditions separately to predict intention to leave clinical practice we found significant baseline effects and change effects. After modelling training and working conditions simultaneously, we found evidence that the change effect of job autonomy (OR 0.77, p = .005) was associated with intention to leave clinical practice, whereas for the training conditions, only the baseline effects of structured residency training (OR 0.74, p = .017) and dealing with lack of knowledge (OR 0.74, p = .026) predicted intention to leave clinical practice.
Junior doctors undergoing specialty training experience high workload in hospital practice and intense requirements in terms of specialty training. Our study indicates that simultaneously improving working conditions over time and establishing a high standard of specialty training conditions may prevent junior doctors from considering leaving clinical practice after residency training.
Intention to leave clinical practice; Postgraduate residency training; Training conditions; Working conditions
TANK-binding kinase 1 (TBK1) is an important enzyme in the regulation of cellular antiviral effects. TBK1 regulates the activity of the interferon regulatory factors IRF3 and IRF7, thereby playing a key role in type I interferon (IFN) signaling pathways. The structure of TBK1 consists of an N-terminal kinase domain, a middle ubiquitin-like domain (ULD), and a C-terminal elongated helical domain. It has been reported that the ULD of TBK1 regulates kinase activity, playing an important role in signaling and mediating interactions with other molecules in the IFN pathway. In this study, we present the crystal structure of the ULD of human TBK1 and identify several conserved residues by multiple sequence alignment. We found that a hydrophobic patch in TBK1, containing residues Leu316, Ile353, and Val382, corresponding to the “Ile44 hydrophobic patch” observed in ubiquitin, was conserved in TBK1, IκB kinase epsilon (IKKε/IKKi), IκB kinase alpha (IKKα), and IκB kinase beta (IKKβ). In comparison with the structure of the IKKβ ULD domain of Xenopus laevis, we speculate that the Ile44 hydrophobic patch of TBK1 is present in an intramolecular binding surface between ULD and the C-terminal elongated helices. The varying surface charge distributions in the ULD domains of IKK and IKK-related kinases may be relevant to their specificity for specific partners.
TBK1; ubiquitin-like domain; crystal structure; hydrophobic patch
Pausing of RNA polymerase II (Pol II) 20-60 bp downstream of transcription start sites is a major checkpoint during transcription in animal cells. Mechanisms that control pausing are largely unknown. We developed permanganate-ChIP-seq to evaluate the state of Pol II at promoters throughout the Drosophila genome, and a biochemical system that reconstitutes promoter-proximal pausing to define pausing mechanisms. Stable open complexes of Pol II are largely absent from the transcription start sites of most mRNA genes, but are present at snRNA genes and the highly transcribed heat shock genes following their induction. The location of the pause is influenced by the timing between when NELF loads onto Pol II and how fast Pol II escapes the promoter region. Our biochemical analysis reveals that the sequence-specific transcription factor, GAF, orchestrates efficient pausing by recruiting NELF to promoters before transcription initiation and by assisting in loading NELF onto Pol II after initiation.
promoter proximal pausing; RNA polymerase II; GAGA factor; NELF; permanganate-ChIP-seq
The biological role of interleukin-37 (IL-37) in cancer is large unknown. Through immunohistochemical detection using 163 primary hepatocellular carcinoma (HCC) clinical specimens, we found the expression of IL-37 was decreased in tumor tissues, and the expression level was negatively correlated with tumor size. High expression of IL-37 in HCC tumor tissues was associated with better overall survival (OS) and disease-free survival (DFS). IL-37 expression in tumor tissues was positively associated with the density of tumor-infiltrating CD57+ natural killer (NK) cells, but not with the CD3+ and CD8+ T cells. Consistently, in vitro chemotaxis analysis showed that IL-37- overexpressing HCC cells could recruit more NK cells. The in vivo mouse model experiments also revealed that overexpression IL-37 in HCC cells significantly delayed tumor growth and recruited more NK cells into tumors tissues. Our finding suggested that IL-37 might play an important role for the prognosis of HCC patients via regulating innate immune-action.
The structural health monitoring system (SHMS) provides an effective tool to conduct full-scale measurements on existing bridges for essential research on bridge wind engineering. In July 2008, Typhoon Fung-Wong lashed China and hit Sutong cable-stayed bridge (SCB) in China. During typhoon period, full-scale measurements were conducted to record the wind data and the structural vibration responses were collected by the SHMS installed on SCB. Based on the statistical method and the spectral analysis technique, the measured data are analyzed to obtain the typical parameters and characteristics. Furthermore, this paper analyzed the measured structural vibration responses and indicated the vibration characteristics of the stay cable and the deck, the relationship between structural vibrations and wind speed, the comparison of upstream and downstream cable vibrations, the effectiveness of cable dampers, and so forth. Considering the significance of damping ratio in vibration mitigation, the modal damping ratios of the SCB are identified based on the Hilbert-Huang transform (HHT) combined with the random decrement technique (RDT). The analysis results can be used to validate the current dynamic characteristic analysis methods, buffeting calculation methods, and wind tunnel test results of the long-span cable-stayed bridges.
Manganese superoxide dismutase (MnSOD), a major antioxidant enzyme within the mitochondria, is responsible for the detoxification of free radicals generated by cellular metabolism and environmental/therapeutic irradiation. Cell cycle-dependent kinase Cdk1, along with its regulatory partner CyclinB1, plays important roles in the regulation of cell cycle progression as well as in genotoxic stress response. Herein, we identified the presence of the minimal Cdk1 phosphorylation consensus sequence ([S/T]-P; Ser106) in human MnSOD, suggesting Cdk1 as a potential upstream kinase of MnSOD. A substantial amount of CyclinB1/Cdk1 was found to localize in the mitochondrion upon irradiation. The enhanced Cdk1/MnSOD interaction and MnSOD phosphorylation were detected in both the irradiated human cells and mouse tissues. We report that CyclinB1/Cdk1 can regulate MnSOD through reversible Ser106 phosphorylation, both in vivo and in vitro. The CyclinB1/Cdk1-mediated MnSOD Ser106 resulted in increased MnSOD activity and stability, along with improved mitochondrial function and cellular resistance to radiation-induced apoptosis. These results demonstrate a unique pro-survival mechanism by which cells enhance the survival via CyclinB1/Cdk1-mediated MnSOD activation under genotoxic stress conditions.
MnSOD; CyclinB1/Cdk1; radioadaptive response
Due to the popularity of video-assisted thoracic surgery (VATS) techniques in clinical, thymoma patients via VATS thymectomy are increasing rapidly. However, compared with open thymectomy, the potential superiorities and defects of VATS thymectomy remain controversial.
A number of 129 patients who underwent thymectomy of early stage thymoma (Masaoka stage I and stage II) in one single center from January 2007 to September 2013 were selected in this retrospective study. Of those patients, 38 thymoma patients underwent VATS thymectomy (VATS group) and 91 underwent open thymectomy (open group) via either transsternal  or transthoracic approach  in the same period. The postoperative variables, which included postoperative hospital length of stay (LOS), the intensive care unit (ICU) LOS, the entire resection ratio, the number of thoracic drainage tubes, the quantity of output and duration of drainage, were analyzed. Meanwhile, the operation time and blood loss were considered as intraoperative variables.
All thymoma patients in the analysis included 19 thymoma patients with myasthenia gravis, among which five patients via VATS thymectomy and 14 patients via open thymectomy respectively. There was no death or morbidity due to the surgical procedures perioperatively. The ICU LOS, operation time, entire resection ratio, and the number of chest tubes were not significantly different in two groups. The postoperative hospital LOS of VATS thymectomy was shorter than that of open thymectomy (5.26 versus 8.32 days, P<0.001). The blood loss of VATS thymectomy was less than open thymectomy (114.74 versus 194.51 mL, P=0.002). Postoperatively, the quantity of chest tubes output in VATS group was less than that in open thymectomy group (617.86 versus 850.08 mL, P=0.007) and duration of drainage in VATS group was shorter than that in open thymectomy group (3.87 versus 5.22 days, P<0.001).
VATS thymectomy is a safe and practicable treatment for early-stage thymoma patients. Thymoma according with Masaoka staging I-II without evident invading seems to be performed through VATS approach appropriately, which has shorter postoperative hospital LOS, less blood loss and less restrictions to activities, hence patients will recover sooner.
Thymoma; thymectomy; video-assisted thoracic surgery (VATS); open surgery
Depression is a major mental health problem during adolescence. This study, using a sample of Chinese adolescents, examined the separate and combined effects of perceived school-related stress and of family socioeconomic status (SES) on the prevalence of depressive symptoms. A total of 1774 Chinese students from Grades 7–12 were recruited into our questionnaire survey. School-related stress was measured by the Effort-Reward Imbalance Questionnaire-School Version, family SES was assessed by a standardized question, and depressive symptoms were evaluated by the Center for Epidemiological Studies Depression Scale for Children. Multivariate logistic regression was applied, adjusting for age, gender, grade, smoking, alcohol drinking and physical activity. It was found that high school-related stress and low family SES were associated with elevated odds of depressive symptoms, respectively. The effect of school-related stress was particularly strong in low SES group. In adolescents with both high stress at school and low SES, the odds ratio was 9.18 (95% confidence interval = 6.53–12.89) compared to the reference group (low stress at school and high SES). A significant synergistic interaction effect was observed (synergy index = 2.28, 95% confidence interval = 1.56–3.32). The findings indicated that perceived school-related stress, in terms of effort-reward imbalance, was related to depressive symptoms in this sample of Chinese adolescents. The strong interaction with family SES suggests that health promoting efforts in school settings should be targeted specifically at these socially deprived groups.
school-related stress; effort-reward imbalance; socioeconomic status; depression; adolescents; China
Effectiveness of drinking water treatment, in particular pathogen control during the water treatment process, is always a major public health concern. In this investigation, the application of PCR-DGGE technology to the analysis of microbial community structures and dynamics in the drinking water treatment process revealed several dominant microbial populations including: α-Proteobacteria, β-Proteobacteria, γ-Proteobacteria, Bacteroidetes, Actinobacteria Firmicutes and Cyanobacteria. α-Proteobacteria and β-Proteobacteria were the dominant bacteria during the whole process. Bacteroidetes and Firmicutes were the dominant bacteria before and after treatment, respectively. Firmicutes showed season-dependent changes in population dynamics. Importantly, γ-Proteobacteria, which is a class of medically important bacteria, was well controlled by the O3/biological activated carbon (BAC) treatment, resulting in improved effluent water bio-safety.
drinking water; advanced treatment; bacteria; microbial community structures