MDT: semi-supervised medical image segmentation with mixup-decoupling training.

Objective. In the field of medicine, semi-supervised segmentation algorithms hold crucial research significance while also facing substantial challenges, primarily due to the extreme scarcity of expert-level annotated medical image data. However, many existing semi-supervised methods still process labeled and unlabeled data in inconsistent ways, which can lead to knowledge learned from labeled data being discarded to some extent. This not only lacks a variety of perturbations to explore potential robust information in unlabeled data but also ignores the confirmation bias and class imbalance issues in pseudo-labeling methods.Approach. To solve these problems, this paper proposes a semi-supervised medical image segmentation method 'mixup-decoupling training (MDT)' that combines the idea of consistency and pseudo-labeling. Firstly, MDT introduces a new perturbation strategy 'mixup-decoupling' to fully regularize training data. It not only mixes labeled and unlabeled data at the data level but also performs decoupling operations between the output predictions of mixed target data and labeled data at the feature level to obtain strong version predictions of unlabeled data. Then it establishes a dual learning paradigm based on consistency and pseudo-labeling. Secondly, MDT employs a novel categorical entropy filtering approach to pick high-confidence pseudo-labels for unlabeled data, facilitating more refined supervision.Main results. This paper compares MDT with other advanced semi-supervised methods on 2D and 3D datasets separately. A large number of experimental results show that MDT achieves competitive segmentation performance and outperforms other state-of-the-art semi-supervised segmentation methods.Significance. This paper proposes a semi-supervised medical image segmentation method MDT, which greatly reduces the demand for manually labeled data and eases the difficulty of data annotation to a great extent. In addition, MDT not only outperforms many advanced semi-supervised image segmentation methods in quantitative and qualitative experimental results, but also provides a new and developable idea for semi-supervised learning and computer-aided diagnosis technology research.

Terminal Residue and Dietary Risk Assessment of Atrazine and Isoxaflutole in Corn Using High-Performance Liquid Chromatography-Tandem Mass Spectrometry.

Isoxaflutole and atrazine are representative pesticides for weed control in corn fields. Formulations containing these two pesticides have been registered in China, and their residues may threaten food safety and human health. In this study, a method for simultaneous determination of isoxaflutole, atrazine, and their metabolites in fresh corn, corn kernels, and corn straw was established based on modified QuEChERS pre-treatment and high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The linearity of seven compounds was good (R2 ≥ 0.9912), and the matrix effect was 48.5-77.1%. At four spiked levels of 0.01, 0.02, 0.05, and 0.5 mg kg-1, all compounds' average recovery was 76% to 116%, with relative standard deviation (RSD) less than 18.9%. Field experiments were conducted in Liaoning, Heilongjiang, Inner Mongolia, Shanxi, Beijing, and Yunnan provinces to study the terminal residues. The terminal residues of all compounds were below the LOQ (0.01 mg kg-1) in fresh corn and corn kernels, and atrazine residues in corn straw ranged from <0.05 mg kg-1 to 0.17 mg kg-1. Finally, a dietary risk assessment was conducted based on residues from field trials, food consumption, and acceptable daily intake (ADI). For all populations, the chronic dietary risk probability (RQc) of atrazine was between 0.0185% and 0.0739%, while that of isoxaflutole was 0.0074-0.0296%, much lower than 100%. The results may provide scientific guidance for using isoxaflutole and atrazine in corn field ecosystems.

Simultaneous Determination of 54 Pesticides in Proso Millet Using QuEChERS with Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS).

To assess the potential risks posed to the environment and human health, analyzing pesticide residues in proso millet is important. This paper aimed to develop a modified QuEChERS method with liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the analysis of 54 pesticide residues in proso millet. Parameters including the mobile phase of the instrument, the acidity of the extraction solvent, and the type of absorbents were optimized to provide satisfactory performance. The method was validated concerning linearity, limit of quantification (LOQ), matrix effect, accuracy, and precision. In detail, the linearity of the matrix-matched calibration curve was acceptable with correlation coefficients (R2) higher than 0.99. The mean recovery was in the range of 86% to 114% with relative standard deviations (RSDs) ≤ 20% (n = 5). The LOQ was determined to be 0.25-10 µg/kg. The developed method was feasible for the determination of multiple pesticide residues in proso millet.

Dissipation, Processing Factors and Dietary Exposure Assessment of Myclobutanil in Tomato.

Myclobutanil residue poses a potential threat to consumers' health. This work aims to investigate the degradation behavior, residue levels, processing factors (PFs) and dietary risk of myclobutanil in tomato. Myclobutanil was analyzed using a modified quick, easy, cheap, effective, rugged, safe (QuEChERS) method combined with ultra-performance liquid chromatography-mass spectrometry (UPLC-MS/MS), and average recoveries ranged from 82% to 102% with relative standard deviations RSDs ≤ 9.1%. After spraying myclobutanil miscible oil under field conditions, the initial concentration of myclobutanil was 0.055 mg/kg, and its dissipation followed the first-order kinetics equation with a half-life of 2.88 days. Myclobutanil was mainly present in the tomato skin, and its concentration was about four times that in the whole tomato. The initial concentration of myclobutanil in raw tomato was 0.100 mg/kg. After washing, peeling, homogenization, simmering and canning, the residual level of myclobutanil decreased to 0.067 mg/kg, 0.023 mg/kg, 0.013 mg/kg, 0.044 mg/kg and 0.041 mg/kg, respectively. Although the procedure of simmering led to an increase in myclobutanil concentration, the PFs were all less than 1 in the whole process, showing that the processing procedure significantly decreased the residual level of myclobutanil canned tomato paste in comparison with the raw agricultural commodity. Washing, peeling, and homogenization played critical roles in reducing pesticide residues. The residues of myclobutanil during the processing of tomato pose low dietary exposure risks to consumers in China, which were acceptable. However, the acute and chronic risk quotient for children revealed that it was necessary to monitor the dietary exposure of pesticide residues for children closely.

The Synaptic and Circuit Functions of Vitamin D in Neurodevelopment Disorders.

Vitamin D deficiency/insufficiency is a public health issue around the world. According to epidemiological studies, low vitamin D levels have been associated with an increased risk of some neurodevelopmental disorders, including autism spectrum disorder (ASD) and attention-deficit hyperactivity disorder (ADHD). Animal models reveal that vitamin D has a variety of impacts on the synapses and circuits in the brain. A lack of vitamin D affects the expression of synaptic proteins, as well as the synthesis and metabolism of various neurotransmitters. Depending on where vitamin D receptors (VDRs) are expressed, vitamin D may also regulate certain neuronal circuits through the endocannabinoid signaling, mTOR pathway and oxytocin signaling. While inconsistently, some data suggest that vitamin D supplementation may be able to reduce the core symptoms of ASD and ADHD. This review emphasizes vitamin D's role in the synaptic and circuit mechanisms of neurodevelopmental disorders including ASD and ADHD. Future application of vitamin D in these disorders will depend on both basic research and clinical studies, in order to make the transition from the bench to the bedside.

The Residue and Dietary Risk Assessment of Spirotetramat and Its Four Metabolites in Cabbage Using Ultra-High-Performance Liquid Chromatography-Tandem Mass Spectrometry.

Spirotetramat is a potential tetronic acid pesticide for controlling various pests with piercing-sucking mouthparts. To clarify its dietary risk on cabbage, we established an ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method and then investigated the residual levels of spirotetramat and its four metabolites in cabbage collected from field experiments under good agricultural practices (GAPs). The average recoveries of spirotetramat and its metabolites in cabbage were 74~110%, while the relative standard deviation (RSD) was 1~6%, and the limit of quantitation (LOQ) was 0.01 mg kg-1. The terminal residue of spirotetramat was in the range of <0.05~0.33 mg kg-1, the chronic dietary risk (RQc) was 17.56%, and the acute dietary risk (RQa) was 0.025~0.049%, which means an acceptable dietary intake risk. This study provides data to guide on the use of spirotetramat and to establish the maximum residue limits (MRLs) of spirotetramat on cabbage.

Network Analysis of ADHD Symptoms and Cognitive Profiles in Children.

Purpose: Although many studies have reported the cognitive profiles in attention-deficit/hyperactivity disorder (ADHD), the interactions between ADHD symptoms and the patients' cognitive profiles have not been carefully examined through the network analysis. Here, in this study, we systematically analyzed the ADHD patents' symptoms and cognitive profiles, and identified a set of interactions between ADHD symptoms and cognitive domains using the network approach. Patients and Methods: A total of 146 children with ADHD, 6 to 15 years of age, were included in the study. All participants were assessed by the Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV) test. The patients' ADHD symptoms were evaluated by the Vanderbilt ADHD parent and teacher rating scales. GraphPad Prism 9.1.1 software was used for descriptive statistics and R 4.2.2 was used for network model construction. Results: The ADHD children in our sample showed lower scores for full scale intelligence quotient (FSIQ), verbal comprehension index (VCI), processing speed index (PSI) and working memory index (WMI). Among all the ADHD core symptoms and comorbid symptoms, the academic ability, inattention symptoms and mood disorder showed direct interaction with the cognitive domains of WISC-IV. In addition, oppositional defiant of the ADHD comorbid symptoms, and perceptual reasoning of the cognitive domains exhibited the highest strength centrality in the ADHD-Cognition network based on parent ratings. Classroom behaviors of the ADHD functional impairment, and verbal comprehension of the cognitive domains exhibited the highest strength centrality in the network based on teacher ratings. Conclusion: We highlighted the importance of considering the interactions between the ADHD symptoms and cognitive properties when designing the intervention plans for the ADHD children.

Generalized fiducial methods for testing the homogeneity of a three-sample problem with a mixture structure.

Recently, the likelihood ratio (LR) test was proposed to test the homogeneity of a three-sample model with a mixture structure. Because of the presence of the mixture structure, the null limiting distribution of the LR test has a complicated supremum form, which leads to challenges in determining p-values. In addition, the LR test cannot control type-I errors well under small to moderate sample size. In this paper, we propose seven generalized fiducial methods to test the homogeneity of the three-sample model. Via simulation studies, we find that our methods perform significantly better than the LR test method in controlling the type-I errors under small to moderate sample size, while they have comparable powers in most cases. A halibut data example is used to illustrate the proposed methods.

Efficacy and safety of Xuefu Zhuyu Granules combined with western medicine in the treatment of angina pectoris of coronary heart disease: A study protocol of a randomized, double-blind, placebo-controlled clinical trial.

BACKGROUND: Despite advances in treatment strategies for coronary heart disease, angina pectoris remains a major cardiovascular disease causing death worldwide. For patients with angina pectoris of coronary heart disease, new or adjuvant treatment regimens are needed. The available evidence suggests that Xuefu Zhuyu Granules combined with Western medicine has advantages in the treatment of angina pectoris of coronary heart disease, but whether its efficacy has a placebo effect and whether it can be used as an adjuvant regimen for the treatment of angina pectoris of coronary heart disease remains controversial. METHODS: This is a prospective, randomized, double-blind, placebo-controlled trial to study the efficacy and safety of Xuefu Zhuyu Granules combined with Western medicine in the treatment of angina pectoris of coronary heart disease. Participants will be randomly divided into a treatment group or a control group, and all patients will receive Western medicine treatment based on guideline recommendations. On this basis, the treatment group orally takes Xuefu Zhuyu Granules and the control group orally takes Xuefu Zhuyu Granules mimic, and are followed up for 24 weeks after 12 weeks of continuous treatment. The observation indexes include: cardiac function parameters (left ventricular end-diastolic diameter; left ventricular end-systolic diameter; left ventricular ejection fraction, blood lipid levels (total cholesterol; triacylglycerol; low-density lipoprotein cholesterol; high-density lipoprotein cholesterol), the number of angina attacks per week, total amount of nitroglycerin tablets taken, and adverse reactions. Finally, SPSS22.0 (IBM Company, New York, NY) software will be used for statistical analysis of the data. DISCUSSION: This study will evaluate the efficacy and safety of Xuefu Zhuyu Granules combined with Western medicine in the treatment of angina pectoris of coronary heart disease. The results of this study will verify whether the efficacy of Xuefu Zhuyu Granules in the treatment of angina pectoris of coronary heart disease belongs to the placebo effect, which will also provide a reference for the clinical use of Xuefu Zhuyu Granules as a supplementary scheme for the treatment of angina pectoris of coronary heart disease.

Revealing the magic of acupuncture based on biological mechanisms: A literature review.

Acupuncture has been used to treat various disease for more than 3,000 years in China and other Asian countries. As a complementary and alternative therapy, it has gained increasing popularity and acceptance among public and healthcare professionals in the West. Over the past few decades, basic and clinical research on acupuncture has made considerable progress. Internationally recognized evidence from clinical studies has been published, a preliminary system to clinically evaluate acupuncture has been created, and some clinical guidelines have been formulated. Moreover, scientists have strived to explore the physiological and biological mechanisms of acupuncture. Some basic studies have indicated that acupuncture has various actions, such as analgesic, muscle relaxing, anti-inflammatory, mild anxiolytic, and antidepressant actions, with possible biological mechanisms such as central sensitization, neurotransmitters, the intestinal flora, immune regulation, oxidative stress, and neuroinflammation. The current review describes the common indications for acupuncture recommended by the WHO and the use of acupuncture in China, the United States, Australia, and several other countries. This review then summarized the mechanisms by which acupuncture treats common conditions including lower back pain (LBP), ischemic stroke, depression, and irritable bowel syndrome (IBS) and it also cited specific acupuncture points for treating these conditions. The hope is that this review will provide useful information for both acupuncturists and researchers to better understand the mechanisms of acupuncture and reasons for its usage.

Use of the RBANS to Evaluate Cognition in Patients with Schizophrenia and Metabolic Syndrome: a Meta-Analysis of Case-Control Studies.

Schizophrenia is associated with an increased risk of metabolic syndrome (MetS), which is an important risk factor for developing cognitive impairment in the general population. A few case-control studies have explored the relationship between MetS and cognitive deficits in individuals with schizophrenia but with inconsistent findings. This meta-analysis of case-control studies was carried out to explore the association between MetS and cognitive performance in patients with schizophrenia. Only case-control studies assessing the association of cognitive function and MetS in patients with schizophrenia were identified. Cognitive function was assessed using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) scale. Six case-control studies (n = 992) comparing cognition between patients with schizophrenia with MetS (n = 426) and those without MetS (n = 566) using the RBANS were identified. Compared to patients with schizophrenia without MetS, patients with schizophrenia and MetS had significantly more impairments in RBANS total scores [standardized mean difference (SMD) = -0.26, 95% confidence interval (CI): -0.51 to -0.02; I2 = 72%; p = 0.03], immediate memory (SMD = -0.32, 95% CI: -0.54 to -0.10; I2 = 66%; p = 0.005), attention (SMD = -0.29, 95% CI: -0.56 to -0.02; I2 = 77%; p = 0.03), and delayed memory (SMD = -0.24, 95% CI: -0.46 to -0.03; I2 = 64%; p = 0.03). No group difference was found regarding visuospatial skills and language (p > 0.05). This meta-analysis found that schizophrenia patients with MetS had worse performance on certain cognitive tasks than non-MetS patients.

Finite Element Analysis of a Novel Anterior Locking Plate for Thoracolumbar Burst Fracture.

PURPOSE: The finite element analysis method was used to explore the biomechanical stability of a novel locking plate for thoracolumbar burst fracture fusion fixation. METHODS: The thoracolumbar CT imaging data from a normal volunteer was imported into finite software to build a normal model and three different simulated surgical models (the traditional double-segment fixation model A, the novel double-segment fixation model B, and the novel single-segment fixation model C). An axial pressure (500 N) and a torque (10 Nm) were exerted on the end plate of T12 to simulate activity of the spine. We recorded the range of motion (ROM) and the maximum stress value of the simulated cages and internal fixations. RESULTS: Model A has a larger ROM in all directions than model B (flexion 5.63%, extension 38.21%, left rotation 46.51%, right rotation 39.76%, left bending 9.45%, and right bending 11.45%). Model C also has a larger ROM in all directions than model B (flexion 555.63%, extension 51.42%, left rotation 56.98%, right rotation 55.42%, left bending 65.67%, and right bending 59.47%). The maximum stress of the cage in model A is smaller than that in model B except for the extension direction (flexion 96.81%, left rotation 175.96%, right rotation 265.73%, left bending 73.73%, and right bending 171.28%). The maximum stress value of the internal fixation in model A is greater than that in model B when models move in flexion (20.23%), extension (117.43%), and left rotation (21.34%). CONCLUSION: The novel locking plate has a smaller structure and better performance in biomechanical stability, which may be more compatible with minimally invasive spinal tubular technology.

Cyclic Mechanical Stretch Ameliorates the Degeneration of Nucleus Pulposus Cells through Promoting the ITGA2/PI3K/AKT Signaling Pathway.

BACKGROUND: Intervertebral disc degeneration (IVDD) is one of the major causes of low back pain and motor deficiency. Nucleus pulposus (NP) degeneration plays a key role in the process of IVDD. The mechanical and biological interactions involved in NP degeneration have not been elucidated. The present study is aimed at investigating the effect and mechanism of cyclic mechanical stretch in regulating the function and degeneration of NP cells. METHODS: NP cells were subjected to cyclic tensile stress (10% deformation) of 0.1 Hz for 8640 cycles. Cell proliferation was conducted through the MTT assay. The cell cycle and apoptosis were detected by flow cytometry. A gene expression profile chip was used to analyze the differentially expressed genes between the tensile stress group and the control group. Enrichment analysis of Gene Ontology (GO) annotation and signaling pathways were analyzed. Western blot and RNA interference were carried out to investigate the role of the ITGA2/PI3K/AKT pathway in the effect of cyclic mechanical stretch on NP cells. RESULTS: NP cells exhibited a greater (P < 0.05) growth rate in the tensile stress group compared to the control group. Cyclic mechanical stress significantly promoted the cell cycle transition of NP cells from the S phase to the G2/M phase. A fewer proportion of apoptotic cells were found in the tensile stress group (P < 0.05), indicating that cyclic mechanical stretch inhibits NP cell apoptosis. Microarray analysis revealed 689 significant differentially expressed genes between the two groups (P < 0.05), of which 333 genes were upregulated and another 356 genes were downregulated. Cyclic mechanical stretch altered the expression of 31 genes involved in the ITGA2/PI3K/AKT pathway and remarkably promoted this pathway in NP cells. Downregulation of ITGA2 and AKT further demonstrated that the PI3K/AKT pathway was responsible for the proliferation and COL2A1 expression of NP cells upon cyclic mechanical stretch. CONCLUSIONS: Cyclic mechanical stretch promoted the proliferation and cell cycle and reversely inhibited the apoptosis of NP cells. Cyclic mechanical stretch promoted COL2A1 expression and ameliorated the degeneration of NP cells via regulation of the ITGA2/PI3K/AKT signaling pathway. Our results may provide a potential target and a possibility of IVDD disease treatment by ameliorating the degenerative changes.

Patient and Perioperative Factors Influencing the Functional Outcomes and Mortality in Elderly Hip Fractures.

This study aimed to evaluate the functional outcomes and mortality following hip fracture surgery in elderly patients, and to identify the associated risk factors. Between January 2016 and December 2017, 480 consecutive patients were finally included for data analyses. The Harris score and Barthel index were used to evaluate the hip function and ability to perform activities of daily living (ADL). Univariate and multivariate logistics regression analyses were performed to determine the independent risk factors for mortality, poor hip function or poor ability to perform ADL. The mortality rate was 15.6% (75/480). In the survivors, poor outcome developed in 133 (32.8%) patients and poor ADL was in 72 (17.8%) patients. The independent factors that influenced mortality were advanced age (p = 0.033), male gender (0.031), living in rural area (p < 0.001), self-reported diabetes (p = 0.005), tumor (p = 0.024), preoperative delay >7 days (p = 0.020), postoperative drainage use (p = 0.034), WBC > 10 × 109/L (p = 0.005), reduced RBC (p = 0.011), PLT < 100 × 109/L (p < 0.001), ALB < 35 g/L (p < 0.001) and CK > 200 U/L (p = 0.003). The independent factors that influenced the hip function were male gender (p = 0.009), WBC > 10 × 109/L (p < 0.001), lower HBG (p = 0.005), and ALB < 35 g/L (p < 0.001). The independent factors that influenced the ability to perform ADL were diagnosis of trochanteric fracture (p = 0.048), preoperative delay > 7 days (p = 0.027), postoperative drainage use (p = 0.010), elevated WBC (p = 0.020), lower HGB (p < 0.001), PLT < 100 × 109/L (p = 0.002), and ALB < 35 g/L (p < 0.001). Although most of risk factors were not modifiable, they aid in patient individual risk evaluation, risk stratification, and counseling patients or relatives.

Therapeutic effects of coronary granulocyte colony-stimulating factor on rats with chronic ischemic heart disease.

BACKGROUND: The aim of this study was to evaluate the therapeutic effects of coronary granulocyte colony-stimulating factor (G-CSF) on rats with chronic ischemic heart disease (CIHD). METHODS: Thirty healthy rats were randomly divided into control, subcutaneous and intracoronary G-CSF injection groups (n = 10) after the CIHD model was established. Left ventricular ejection fraction (LVEF), myocardial injury area, myocardial perfusion area and viable myocardium were observed by coronary angiography, dual-isotopic myocardial imaging and first-pass delayed myocardial perfusion magnetic resonance imaging (MRI) before modeling as well as 2 and 4 weeks after surgery. RESULTS: The peak times of peripheral blood and subcutaneous G-CSF levels were 3 and 5 days after mobilization, respectively. The peripheral blood CD34+/CD133+ cell ratio of subcutaneous or intracoronary G-CSF injection group significantly exceeded that of the control group (P < 0.05). The distal stenosis degrees of target lesions in subcutaneous and intracoronary G-CSF injection groups were significantly lower than that of the control group (P < 0.05). Compared with the situation before mobilization, LVEF was significantly improved after 2 weeks in intracoronary and subcutaneous G-CSF injection groups (P < 0.01). Their infarcted myocardial areas were reduced, the left ventricular remodeling was relieved, the percentage of viable myocardium was increased, angiogenesis was promoted and cardiomyocyte apoptosis was inhibited. CONCLUSION: Intracoronary G-CSF injection is safe and effective as subcutaneous injection, improving the cardiac function of CIHD rats.

The effect of methamphetamine abuse on dental caries and periodontal diseases in an Eastern China city.

BACKGROUND: Dental diseases are among the most frequently reported health problems in drug abusers. However, few studies have been conducted on oral health of methamphetamine (meth) abusers in China. The aim of the present study was to investigate the caries and periodontal health profile of former meth abusers in Eastern China. METHODS: A cross-sectional study was conducted on 162 former meth abusers in the male Zhoushan Compulsory Detoxification Center. A standardized questionnaire, which collected information about age, drug-use duration / pattern, oral hygiene habit and systemic diseases, was administered. Then, a dental examination was performed to investigate the severity of dental caries and periodontal diseases. In evaluating dental caries, the prevalence of dental caries, the scores of decayed teeth (DT), missing teeth (MT), filled teeth (FT), and decayed, missing, filled teeth (DMFT) were recorded. In evaluating periodontal diseases, community periodontal index (CPI), and the prevalence of gingival bleeding, dental calculus, periodontal pocket and loose teeth, were recorded. Additionally, the non-parametric test was adopted to analyze the potential risk factors via SPSS. RESULTS: All the participants abused meth by inhalation. The mean scores of DT, MT, FT and DMFT in the former meth users were 2.72 ± 2.78, 3.07 ± 3.94, 0.33 ± 1.03 and 6.13 ± 5.20 respectively. The prevalence of gingival bleeding, dental calculus, periodontal pocket and loose teeth was 97.53%, 95.68%, 51.23% and 9.26% respectively. The DT, DMFT and CPI scores in those who had abused meth for longer than 4 years were significantly higher than those who abused for less than 4 years (P = 0.039, 0.045, P < 0.001, respectively). The DT score in those who brushed their teeth more than twice a day were significantly lower than those who brushed less (P = 0.018). CONCLUSIONS: The status of caries and periodontal diseases among former male meth users in Eastern China was poor. Prolonged drug abuse and lower frequency of tooth brushing may be the risk factors of their poor status of caries and periodontal diseases.

Efficacy of dexmedetomidine on postoperative nausea and vomiting: a meta-analysis of randomized controlled trials.

PURPOSE: Postoperative nausea and vomiting (PONV) is a frequent complication in postoperative period. The aim of the current meta-analysis was to assess the efficacy of dexmedetomidine on PONV. METHODS: Two researchers independently searched PubMed, Embase and Cochrane Central Register of Controlled Trials for randomized controlled trials (RCTs). The meta-analysis was performed with Review Manager. RESULTS: Eighty-two trials with 6,480 patients were included in this meta-analysis. Dexmedetomidine reduced postoperative nausea (Risk Ratio (RR) = 0.61, 95% confidence interval (CI): 0.50 to 0.73) and vomiting (RR = 0.48, 95% CI: 0.36 to 0.64) compared with placebo, with an effective dose of 0.5 ug/kg (RR = 0.46, 95% CI: 0.34 to 0.62) and 1.0 ug/kg (RR = 0.29, 95% CI: 0.12 to 0.75), respectively. The antiemetic effect can only be achieved intravenously, not epidurally or intrathecally. The efficacy of dexmedetomidine was similar to that of widely used agents, such as propofol, midazolam etc., but better than opioid analgesics. Moreover, application of dexmedetomidine reduced intraoperative requirement of fentanyl (Standard Mean Difference = -1.91, 95% CI: -3.20 to -0.62). CONCLUSIONS: The present meta-analysis indicates that dexmedetomidine shows superiority to placebo, but not to all other anesthetic agents on PONV. And this efficacy may be related to a reduced consumption of intraoperative opioids.

Efficacy of dexmedetomidine on postoperative nausea and vomiting: a meta-analysis of randomized controlled trials.

PURPOSE: Postoperative nausea and vomiting (PONV) is a frequent complication in postoperative period. The aim of the current meta-analysis was to assess the efficacy of dexmedetomidine on PONV. METHODS: Two researchers independently searched PubMed, Embase and Cochrane Central Register of Controlled Trials for randomized controlled trials (RCTs). The meta-analysis was performed with Review Manager. RESULTS: Eighty-two trials with 6,480 patients were included in this meta-analysis. Dexmedetomidine reduced postoperative nausea (Risk Ratio (RR) = 0.61, 95% confidence interval (CI): 0.50 to 0.73) and vomiting (RR = 0.48, 95% CI: 0.36 to 0.64) compared with placebo, with an effective dose of 0.5 µg/kg (RR = 0.46, 95% CI: 0.34 to 0.62) and 1.0 µg/kg (RR = 0.29, 95% CI: 0.12 to 0.75), respectively. The antiemetic effect can only be achieved intravenously, not epidurally or intrathecally. The efficacy of dexmedetomidine was similar to that of widely used agents, such as propofol, midazolam etc., but better than opioid analgesics. Moreover, application of dexmedetomidine reduced intraoperative requirement of fentanyl (Standard Mean Difference = -1.91, 95% CI: -3.20 to -0.62). CONCLUSIONS: The present meta-analysis indicates that dexmedetomidine shows superiority to placebo, but not to all other anesthetic agents on PONV. And this efficacy may be related to a reduced consumption of intraoperative opioids.

Protective role of isoflurane pretreatment in rats with focal cerebral ischemia and the underlying molecular mechanism.

Inflammation and immunity are important in the pathogenesis of cerebral ischemia. Toll-like receptor 4 (TLR4) is involved in the inflammatory responses of injured brain tissues. Emerging studies have focused on the effect of isoflurane (ISO) pretreatment on cerebral ischemia, however, the association between ISO pretreatment and TLR4 during cerebral ischemia remains to be elucidated. In the present study, the protective role of ISO pretreatment in rats with focal cerebral ischemia reperfusion was investigated and the molecular mechanism was discussed. Using a middle cerebral artery occlusion (MCAO) model, triphenyltetrazolium chloride staining was utilized to measure the infarct volume and brain edema and immunofluorescence staining was used to detect the MCAO-induced TLR4 expression and localization. Western blot analyses were conducted to quantify the protein expression levels of TLR4, myeloid differentiation primary response 88 (MyD88) and nuclear factor (NF)-κB in ischemic brain tissue at different time points. The results demonstrated that, following ISO pretreatment, the neurological deficits, brain edema and cerebral infarct size caused by ischemia/reperfusion were attenuated. The astrocyte and microglial activation in the brain tissue was decreased. In addition, the expression levels of TLR4, MyD88 and NF-κB were decreased. The present study indicated that ISO pretreatment may protect the brain from ischemic damage by downregulating the expression levels of TLR4, MyD88 and NF-κB.

Down-regulation of Homer1b/c attenuates group I metabotropic glutamate receptors dependent Ca²âº signaling through regulating endoplasmic reticulum Ca²âº release in PC12 cells.

The molecular basis for group I metabotropic glutamate receptors (mGluR1 and 5) coupling to membrane ion channels and intracellular calcium pools is not fully understood. Homer is a family of post synaptic density proteins functionally and physically attached to target proteins at proline-rich sequences. In the present study, we demonstrate that Homer1b/c is constitutively expressed in PC12 cells, whereas Homer1a, the immediate early gene product, can be up-regulated by brain derived neurotrophic factor (BDNF) and glutamate. Knockdown of Homer1b/c using specific target small interfering RNA (siRNA) did not interfere the expression of mGluR1, mGluR5 and their downstream effectors, including inositol-1,4,5-trisphosphate receptors (IP3R), phospholipase C (PLC) and Gq proteins. By analyzing Ca(2+) imaging in PC12 cells, we demonstrated that Homer1b/c is an essential regulator of the Ca(2+) release from the endoplasmic reticulum (ER) induced by the activation of group I mGluRs, IP3R and ryanodine receptors (RyR). Furthermore, the group I mGluRs activation-dependent refilling of the Ca(2+) stores in both resting and depolarizing conditions were strongly attenuated in the absence of Homer1b/c. Together, our results demonstrate that in PC12 cells Homer1b/c is a regulator of group I mGluRs related Ca(2+) homeostasis that is essential for the maintenance of normal Ca(2+) levels in the ER.