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Soluble Triggering Receptor Expressed on Myeloid Cells 2 (sTREM2) plays a crucial role in the pathogenesis of Alzheimer’s disease (AD). This review comprehensively examines sTREM2’s involvement in AD, focusing on its regulatory functions in microglial responses, neuroinflammation, and interactions with key pathological processes. We discuss the dynamic changes in sTREM2 levels in cerebrospinal fluid and plasma throughout AD progression, highlighting its potential as a therapeutic target. Furthermore, we explore the impact of genetic variants on sTREM2 expression and its interplay with other AD risk genes. The evidence presented in this review suggests that modulating sTREM2 activity could influence AD trajectory, making it a promising avenue for future research and drug development. By providing a holistic understanding of sTREM2’s multifaceted role in AD, this review aims to guide future studies and inspire novel therapeutic strategies.

Large-scale outbreaks of virus-associated severe diarrhea have occurred in pig populations since 2010. To investigate the prevalence and genetic evolution of the diarrhea-associated viruses responsible for the outbreaks, we tested 1,791 diarrhea samples collected from 213 pig farms in five provinces in southern China between 2021 and 2023. The test results showed that porcine epidemic diarrhea virus (PEDV) was the most frequently detected virus. The prevalence rates ranged from 47.40 to 52.22% in samples and 76.06% (162/213) in pig farms. Porcine rotavirus (PoRV) was the second common virus, with prevalence rates ranging from 25.81 to 50.81% in samples and 72.77%(155/213) in pig farms. Porcine delta coronavirus (PDCoV) was the third common virus, with prevalence rates ranging from 16.33 to 17.48% in samples and 38.50% (82/213) in pig farms. The detection rates of both transmissible gastroenteritis virus (TGEV) and porcine acute diarrheal syndrome coronavirus (SADS-CoV) were very low, less than 1.01% in samples and less than 3.76% in pig farms. In this study, we found SADS-CoV only in piglet diarrhea samples from Jiangxi, Guangdong, and Guangxi provinces in China, with a prevalence rate of 5.16% (11/213) in pig farms. Co-infection with these diarrhea-associated viruses is a common occurrence. The most common co-infections were PEDV and PoRV, with a prevalence rate of 6.64% (119/1,791), followed by PDCoV and PoRV, with a prevalence rate of 4.19% (75/1,791). Phylogenetic analyses showed that PEDV and PEDV variants prevalent in southern China during the past three years clustered into genotype GIIb and recombinant PEDV subtypes. Among the currently endemic PEDV, the most common mutations occurred in the collagenase equivalent (COE) and epitope regions of the spike gene. PoRV strains were mainly dominated by the G9 subtype, followed by the G5, G3 and G4 subtypes. Our results suggest that variant PEDV, PDCoV and PoRV are the main pathogens of swine diarrhea, and singular- or co-infection with pathogenic enteric CoV is common in pig herds in southern China. Therefore, prevention and control of porcine viral diarrhea should be given high attention.

Avian leukosis virus subgroup K (ALV-K) is a new subgroup of avian leukosis virus (ALV) that was first identified in Chinese native chickens in recent years. To further understand the molecular epidemiology and evolutionary diversity of ALV-K, this study investigated the molecular epidemiology of 73,664 chicken plasma samples collected from Jiangxi native chicken flocks. The results showed that ALV-J was the most predominant ALV subtype in Jiangxi native chickens, with a high positivity rate of 4.34%. From 2021 to 2023, there was a gradual upward trend in the proportion of positive numbers of ALV-K among ALV-positive samples, and there was a trend of outbreaks. ALV-J and ALV-K were the main co-infection patterns. Genetic evolutionary analysis based on ALV-K gp85 gene showed that the isolated ALV-K in this study were distributed in various branches of the evolutionary tree with genetic diversity. The homology results showed that the amino acid homology of the isolated ALV-K gp85 gene ranged from 33.9 to 88.1% with the reference strains of subtypes A, B, C, D, E, and J, and from 91.9 to 100% with the other ALV-K reference strains. Multiple mutations were present in the ALV-K gp85, and especially significant mutations were found in the highly variable region hr2. The results of ALV-K replication efficiency showed that the replication efficiency of ALV-K was significantly lower than that of ALV-J. These results enriched the genome sequence data of ALV-K in Chinese geoducks, and laid the foundation for further research on the pathogenesis and prevention of ALV-K.

Estimation of in situ stresses based on back-analysis of measured stress changes and displacements has become an alternative to the direct stress measurement methods. In order to help users conduct own measurement and analysis, this paper presents in detail a field stress back-analysis approach directly from borehole strain changes measured during nearby underground excavation. Essential formulations in major steps and the procedure for the entire analysis process are provided to allow users to follow. The instrument for borehole strain change measurement can be the CSIR or CSIRO stress cells and other borehole strain cells that can measure strains on borehole walls. Strain changes corresponding to the stress changes at a borehole location are calculated in borehole environment. The stress changes due to nearby excavation can be calculated by an analytical model for a single circular opening and simulated by a numerical model for non-circular and multiple openings. These models are based on isotropic, homogeneous and linear elastic assumptions. The analysis of borehole strain changes is accomplished by multiple linear regression based on error minimization and an integrated process provides the best-fit solution directly to the in situ stresses. A statistical technique is adopted for screening outliers in the measurement data, checking measurement compatibility and evaluating the reliability of analysis results. An application example is included to demonstrate the practical application and the analysis procedure.

Aimed at the low accuracy of loudspeaker abnormal sound classification, an abnormal sound classification method based on the combination of adaptive variational mode decomposition (AVMD) and residual convolutional neural network (RCNN) is proposed. In AVMD, the grey wolf optimizer (GWO) algorithm was used to optimize the quadratic penalty factor (α) and modal decomposition number (K) of the variational mode decomposition (VMD), and then the VMD was used to extract the features. Finally, the random forest recursive feature elimination (RF-RFE) algorithm was used to extract the optimal feature data, and residual network (ResNet) was introduced by RCNN-3 to classify abnormal sound based on convolutional neural network (CNN). The experimental results show that the proposed method has better classification accuracy and stability, and its average classification accuracy can reach 99.3%.

Abstract Objectives The objectives of this study were to describe the coronavirus disease caused by SARS-CoV-2 (COVID-19) reinfection evaluation algorithm used in the early phase of the pandemic in Singapore and analyze the clinical and laboratory characteristics of the cases evaluated. Methods We performed a retrospective case-control analysis including all COVID-19 cases evaluated for possible reinfection under the local COVID-19 reinfection evaluation programme between 1 June 2020-30 June 2021. Whole genome sequencing (WGS) was used as confirmatory testing. We compared all reinfection (“RI”) cases against those who were evaluated but eventually assessed not to be reinfection (“non-RI”). Results There were 74 possible reinfection cases evaluated through the programme, of which 32 were subsequently classified as RI. There was strong statistical evidence that RI cases had a longer interval between 1st and 2nd episode (mean 297 days; 95%-confidence interval (CI) 267–327) compared to non-RI cases (mean 186 days; 95%-CI 144–228). The cycle threshold (Ct) value of initial polymerase chain rection (PCR) at 2nd episode was also found to be significantly lower in RI cases (mean 23; 95%-CI 20–26) compared to non-RI cases (mean 34; 95%-CI 32–36). There was no significant difference in the proportion of individuals who had fever, acute respiratory symptoms or asymptomatic in both groups. Delta and beta variants were most commonly identified from WGS and provide indication of re-infection as these were not ‘wild-type’ and were not circulating during the time period of the index infection. Conclusions Using a combination of serologic, microbiologic and genomic criteria to evaluate possible reinfection cases is useful and can provide a framework for evaluation that may be modified for future similar situations.

Objective: To explore the effect of air frying pan treatment on the quality of arrowhead starch. Methods:Taking arrowhead starch as the research object, the effects of thermal cycle mode of air fryer （treated at 160 ℃ for 10 min） on the physical and chemical properties of arrowhead starch with different mesh numbers were investigated. Results: The properties of starch changed after treatment in air fryer, and the properties of starch with different particle sizes were also different after treatment. Under the treatment of air fryer, the viscosity of arrowhead starch with different mesh numbers was significantly different from that of the original starch, the light transmittance increased significantly and the transparency increased differently, and the transparency of starch decreased with the increase of mesh number; At the same time, the gelatinization properties such as freeze-thaw stability also decreased significantly, and the solubility and swelling degree increased. The modified Sagittaria starch particles have broken appearance, shrinkage, increased shape change, and obvious change of characteristic diffraction peak. Conclusion: The air fryer treatment destroyed the particle shape of arrowhead starch to a certain extent, changed the properties of starch itself, which was simpler than other modification methods.

Alzheimer’s disease (AD) is a neurodegenerative disorder characterized by protein aggregation in the brain. Recent studies have revealed the critical role of microglia in AD pathogenesis. This review provides a comprehensive summary of the current understanding of microglial involvement in AD, focusing on genetic determinants, phenotypic state, phagocytic capacity, neuroinflammatory response, and impact on synaptic plasticity and neuronal regulation. Furthermore, recent developments in drug discovery targeting microglia in AD are reviewed, highlighting potential avenues for therapeutic intervention. This review emphasizes the essential role of microglia in AD and provides insights into potential treatments.

ObjectiveTo evaluate the equivalence of 5 Salmonella selective enrichment procedures in standard methods worldwide.MethodsThe growth rates（PR） and the colony characteristics of 5 selective enrichment broths（SC， TTB， RV， MKTTn， SBG） and 5 selective mediums（CAS， XLD， XLT4， HE， BS） were validated according to the GB4789.28—2013. The sensitivity（SE）， the relative trueness（RT） and the acceptable limit（AL） were estimated on highly contaminated foods through the use of 5 protocols combined with 5 selective enrichment broths and 2 selective mediums according to the method of ISO 16140—2：2016. The sensitivity（Se）， the specificity（Sp）， the positive predictive value（PPV） and the negative predictive value（NPV） were simultaneously determined through the use of 10 compound modes combined with selective enrichment broths and selective mediums according to the classical statistical methods.ResultsThe results showed that SC broth had no efficacy in enriching Salmonella enterica serotype Cholerae and Salmonella enterica serotype Cholerae var. Kunzendorf. The CAS and XLD were significantly better than XLT4， HE and BS in identifying typhoidal Salmonella and nontyphoidal Salmonella as well as the phenotype of hydrogen sulfide.Totally 84 samples（22 pieces of meat， 32 pieces of poultry and 30 pieces of aquatic products） were tested. 25 out of the 84（29.76%） were confirmed positive by 5 protocols， and 16 serotypes from 42 isolates were identified. The SE of 5 protocols were 84.00%， 100.00%， 88.00%，88.00% and 92.00%， respectively， but showed no statistically significant difference between each other. The AL of one protocol （SC+TTB） went beyond the limitation of the ISO 16140—2：2016 due to the ineffectiveness of SC broth. The compound mode of RV-CAS had the best comprehensive benefits， while the Se， the Sp， the PPV and the NPV of which were 68.00%， 95.00%， 85.00% and 88.00%， respectively.ConclusionThe ineffectiveness of SC broth reduces the sensitivity of the detection protocol for Salmonella， which could cause a negative deviation， resulting in the threshold exceeding of the Acceptability Limit （AL）. The combinational selective enrichment broth of RV-CAS is recommended to be the optimal mode， with CAS+XLD being recommended to be the optimal selective medium combination. The process of Salmonella serotyping is suggested to be improved in the standard of GB4789.4 to cope with the multi-serotype Salmonella contamination in food chain and be consistent with the international standardization for food microbiology.

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Background: Obesity is defined as an imbalance between energy intake and expenditure, and it is a serious risk factor of non-communicable diseases. Recently many studies have shown that promoting browning of white adipose tissue (WAT) to increase energy consumption has a great therapeutic potential for obesity. Sesamol, a lignan from sesame oil, had shown potential beneficial functions on obesity treatment. Objective: In this study, we used C57BL/6J mice and 3T3-L1 adipocytes to investigate the effects and the fundamental mechanisms of sesamol in enhancing the browning of white adipocytes to ameliorate obesity. Methods: Sixteen-week-old C57BL/6J male mice were fed high-fat diet (HFD) for 8 weeks to establish the obesity models. Half of the obese mice were administered with sesamol (100 mg/kg body weight [b.w.]/day [d] by gavage for another 8 weeks. Triacylglycerol (TG) and total cholesterol assay kits were used to quantify serum TG and total cholesterol (TC). Oil red O staining was used to detect lipid droplet in vitro. Mito-Tracker Green was used to detect the mitochondrial content. Quantitative reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the levels of beige-specific genes. Immunoblotting was used to detect the proteins involved in beige adipocytes formation. Results: Sesamol decreased the content of body fat and suppressed lipid accumulation in HFD-induced obese mice. In addition, sesamol significantly upregulated uncoupling protein-1 (UCP1) protein in adipose tissue. Further research found that sesamol also significantly activated the browning program in mature 3T3-L1 adipocytes, manifested by the increase in beige-specific genes and proteins. Moreover, sesamol greatly increased mitochondrial biogenesis, as proved by the upregulated protein levels of mitochondrial biogenesis, and the inhibition of the proteins associated with mitophagy. Furthermore, β3-adrenergic receptor (β3-AR), protein kinase A-C (PKA-C) and Phospho-protein kinase A (p-PKA) substrate were elevated by sesamol, and these effects were abolished by the pretreatment of antagonists β3-AR. Conclusion: Sesamol promoted browning of white adipocytes by inducing mitochondrial biogenesis and inhibiting mitophagy through the β3-AR/PKA pathway. This preclinical data promised the potential to consider sesamol as a metabolic modulator of HFD-induced obesity.

Defocus is an important factor that causes image quality degradation of optoelectronic tracking equipment in the shooting range. In this paper, an improved blind/referenceless image spatial quality evaluator (BRISQUE) algorithm is formulated by using the image characteristic extraction technology to obtain a characteristic vector (CV). The CV consists of 36 characteristic values that can effectively reflect the defocusing condition of the corresponding image. The image is evaluated and scored subjectively by the human eyes. The subjective evaluation scores and CVs constitute a set of training data samples for the defocusing evaluation model. An image database that contains sufficiently many training samples is constructed. The training model is trained to obtain the support vector machine (SVM) model by using the regression function of the SVM. In the experiments, the BRISQUE algorithm is used to obtain the image feature vector. The method of establishing the image definition evaluation model via SVM is feasible and yields higher subjective and objective consistency.

Entry of circovirus into the host cell nucleus is essential for viral replication during the early stage of infection. However, the mechanisms by which nucleolar shuttle proteins are used during viral replication is still not well understood. Here, we report a previously unidentified nucleolar localization signal in circovirus capsid protein (Cap), and that circovirus hijacks the nucleolar phosphoprotein nucleophosmin-1 (NPM1) to facilitate its replication. Colocalization analysis showed that NPM1 translocates from the nucleolus to the nucleoplasm and cytoplasm during viral infection. Coimmunoprecipitation and glutathione S-transferase pull-down assays showed that Cap interacts directly with NPM1. Binding domain mapping showed that the arginine-rich N-terminal motif 1MTYPRRRYRRRRHRPRSHLG20 of Cap, and residue serine-48 of the N-terminal oligomerization domain of NPM1, are essential for the interaction. Virus rescue experiments showed that all arginine to alanine substitution in the N-terminal arginine-rich motif of Cap resulted in diminished viral replication. Knockdown of NPM1 and substitution of serine-48 in NPM1 to glutamic acid also decreased viral replication. In addition, binding assays showed that the arginine-rich motif of Cap is a nucleolar localization signal. Taken together, our findings demonstrate that circovirus protein Cap is a nucleolus-located, and regulates viral replication by directly binding to NPM1.

Background: Serratia marcescens (S. marcescens) is associated with nosocomial infections with significant morbidity and mortality in the neonatal intensive care units (NICU). We describe the control of a multi-clonal S. marcescens infections outbreak in our tertiary-level NICU and the application of molecular typing using repetitive element palindromic PCR (rep-PCR) and next generation sequencing (NGS) in the investigation. Methods: Outbreak investigation was performed where clinical, spatial and epidemiologic links were established. Screening of all infants in the NICU and the environment was performed. Rep-PCR and NGS methods were used to identify potential environmental sources of infections and clustering among cases. Results: Eleven cases were detected during the outbreak period: mean gestational age 27 weeks (range: 24–32), predominantly male (82%), mean age of infection 24 days (range: 6–51). Six infants were treated for conjunctivitis and one for bacteraemia. Identification of colonized infant via a point prevalence survey and cohorting of all infected/colonized patients were implemented. We performed environmental swabbing of surfaces, water outlets, chlorhexidine hand wash solutions and hand hygiene hand rubs. Both rep-PCR and NGS classified the 11 case isolates into 5 types. No point source was identified except for a single positive environmental isolate from a sink which was clonally distinct from the cases. Conclusion: Identification and cohorting of infected/colonized patient was important in the control of S. marcescens outbreak in the NICU. The utility of rep-PCR was comparable to NGS in providing molecular information to develop S. marcescens outbreak control strategies.

Objective: Ultraviolet B (UVB) mainly acts on the skin epidermis, causing oxidative damage and apoptosis of keratinocytes. Jin Bai Mei Yan Prescription (JBMYP) comprises a variety of antioxidant traditional Chinese medicines (TCM). In this study, we aimed to evaluate the effects of JBMYP on the oxidative damage induced by UVB in human immortalized epidermal keratinocytes (HaCaT) cells. Methods: HaCaT cells were divided into six groups: control group, model (UVB) group, positive (UVB + vitamin E) group, UVB + JBMYP low dose group (160 μg/mL), UVB + JBMYP mode- rate dose group (800 μg/mL), and UVB + JBMYP high dose group (1 600 μg/mL). HaCaT cells were irradiated with UVB and treated with JBMYP for 24 h. Methyl thiazolyl tetrazolium (MTT) assay and real-time unlabeled cell function analyzer were used to assess the cell survival and proliferation rates, respectively. At the same time, the levels of intracellular reactive oxygen species (ROS), lipid peroxide malondialdehyde (MDA), glutathione (GSH), and hydroxyproline (HYP), as well as the activities of antioxidant enzyme superoxide dismutase (SOD) and catalase (CAT) were evaluated using enzyme linked immunosorbent assay (ELISA). Results: Compared with the model group, the survival rate of HaCaT cells in each dosage group of JBMYP was significantly improved (P < 0.05). Further, JBMYP could promote the proliferation of HaCaT cells, leading to a reduction in the contents of MDA and ROS, and increase in the contents of SOD, CAT, GSH and HYP in HaCaT cells. Conclusions: JBMYP has enhanced protective effect on oxidative damage induced by UVB in HaCaT cells.

Flux calibration is an important test item in laboratory calibration experiments of space gaze cameras, which is the basis for obtaining high-precision scientific application data. In the flux calibration of a space gaze camera, the multi-field calibration method is adopted. The instability of the calibration light source will introduce uncertainty during the calibration process. When the spatial camera adopts the gaze imaging mode, the stability of the light source indicates the change in the total energy received by the image plane during the gaze time, which is characterized by relative uncertainty. When the luminous intensity standard lamp runs for the long-term calibration of the stability of the calibration light source, real-time performance and accuracy cannot be guaranteed. Therefore, it is proposed to use a photodetector to measure the stability of the calibration light source for long-term and real-time accurate measurements. First, the stability of the photodetector is calibrated using the light emitting diode; then, the stability of the calibration light source is measured using the photodetector; finally, the stability uncertainty of the calibration light source and the measurement uncertainty of the method is evaluated. The results of the simulation analysis and experimental verification indicate that the gaze time is 5 min and the sampling frequency of the photodetector is 15 Hz; for example, when the flux calibration time is 8 h, the stability uncertainty of the calibration source is 0.42%, and the relative measurement uncertainty is 0.01%.

Background: Obesity has currently become a serious social problem to be solved. Sesamol, a natural bioactive substance extracted from sesame oil, has shown multiple physiological functions, and it might have an effect on the treatment of obesity. Objective: This study was conducted to investigate the therapeutic effect and potential mechanisms of sesamol on the treatment of obesity and metabolic disorders in high-fat diet (HFD)-induced obese mice. Methods: C57BL/6J male mice were fed HFD for 8 weeks to induce obesity, followed by supplementation with sesamol (100 mg/kg body weight [b.w.]/day [d] by gavage) for another 4 weeks. Hematoxylin and eosin staining was used to observe lipid accumulation in adipose tissues and liver. Chemistry reagent kits were used to measure serum lipids, hepatic lipids, serum alanine aminotransferase (ALT), and aspartate aminotransferase (AST) levels. ELISA kits were used to determine the serum insulin and free fatty acid (FFA) levels. Western blotting was used to detect the protein levels involved in lipid metabolism in the liver. Results: Sesamol significantly reduced the body weight gain of obese mice and suppressed lipid accumulation in adipose tissue and liver. Sesamol also improved serum and hepatic lipid profiles, and increased insulin sensitivity. In the sesamol-treated group, the levels of serum ALT and AST decreased significantly. Furthermore, after sesamol treatment, the hepatic sterol regulatory element binding protein-1 (SREBP-1c) decreased, while the phosphorylated hormone sensitive lipase (p-HSL), the carnitine palmitoyltransferase 1α (CPT1α), and the peroxisome proliferator-activated receptor coactivator-1α (PGC1α) increased, which were responsible for the fatty acid synthesis, lipolysis, and fatty acid β-oxidation, respectively. Conclusions: Sesamol had a positive effect on anti-obesity and ameliorated the metabolic disorders of obese mice. The possible mechanism of sesamol might be the regulation of lipid metabolism in the liver.

Summary: Circovirus, comprising one capsid protein, is the smallest nonenveloped virus and induces lymphopenia. Circovirus can be used to explore the cell adhesion mechanism of nonenveloped viruses. We developed a single-molecule fluorescence resonance energy transfer (smFRET) assay to directly visualize the capsid's conformational feature. The capsid underwent reversible dynamic transformation between three conformations. The cell surface receptor heparan sulfate (HS) altered the dynamic equilibrium of the capsid to the high-FRET state, revealing the HS-binding region. Neutralizing antibodies restricted capsid transition to a low-FRET state, masking the HS-binding domain. The lack of positively charged amino acids in the HS-binding site reduced cell surface affinity and attenuated virus infectivity via conformational changes. These intrinsic characteristics of the capsid suggested that conformational dynamics is critical for the structural changes occurring upon cell surface receptor binding, supporting a dynamics-based mechanism of receptor binding.

Automatic body region localization in medical three-dimensional (3D)-CT images is a critical step of computerized body-wide Automatic Anatomy Recognition (AAR) system, which can be applied for radiotherapy planning and interest slices retrieving. Currently, the complex internal structure of human body and time consuming computation are the main challenges for the localization. Therefore, this paper introduces and improves the YOLO-v3 model into the body region localization for these problems. First, seven categories of body regions in a CT volume image I are defined based on the modification version of our previous work. Second, an improved YOLO-v3 model is trained to classify each axial slice into one of the seven categories. Then, the effectiveness of the proposed method is evaluated on 3D-CT images that collected from 220 subjects. The experimental results demonstrate that the slice localizing error is less than 3 NoS (Number of slices), which is competitive to the state-of-the-art methods. Beyond this, our method is simple and computationally efficient owing to its less training time, and the average computational time for localizing a volume CT images is about 3 second, which shows potential for a further application.

Objective To evaluate the efficacy of the local injection of Salvia miltiorrhiza combined with triamcino⁃ lone acetonide and triamcinolone acetonide alone in the treatment of oral submucous fibrosis (OSF). Methods A meta⁃ analysis was performed by searching the related literature. Three randomized controlled trials meeting the inclusion crite⁃ ria were identified. Changes in the Visual Analogue Scale (VAS) score and the degree of mouth opening were included in 172 cases (86 cases in the experimental group and 86 in the control group), and changes in the oral mucosal lesion area were included in 152 cases (76 cases in the experimental group and 76 in the control group). Changes in the VAS score, the degree of mouth opening and the oral mucosal lesion area were compared in the context of the local injection of Salvia miltiorrhiza combined with triamcinolone acetonide and triamcinolone acetonide alone. Results There were no signifi⁃ cant differences between the treatment with Salvia miltiorrhiza combined with triamcinolone acetonide and triamcinolone acetonide alone in reducing the VAS score (P > 0.05). Salvia miltiorrhiza combined with triamcinolone acetonide resulted in a greater increase in the degree of mouth opening than did triamcinolone acetonide (P = 0.05). The reduction in the oral mucosal lesion area induced by Salvia miltiorrhiza combined with triamcinolone acetonide was significantly greater than that induced by triamcinolone acetonide alone (P < 0.05). Conclusion The local injection of Salvia miltiorrhiza com⁃ bined with triamcinolone acetonide is more effective than triamcinolone acetonide alone in the treatment of OSF.

An improved Least Squares Reverse Time Migration (LSRTM) method is proposed in the paper, which can effectively improve convergence speed and imaging accuracy. Firstly, the key techniques in the implementation of LSRTM are discussed. Secondly, a condition factor is introduced in the iteration process of conjugate gradient method. Finally, the imaging effect and performance of the algorithm are analyzed. The experiment results indicate that it can speed up the convergence speed and improve the convergence accuracy, so as to improve the imaging effect. Compared with the conventional LSRTM, the data residual of improved LSRTM can be reduced by about 5%.

This study aimed to investigate the effect of sesamol (SEM) on the protein kinase A (PKA) pathway in obesity-related hepatic steatosis treatment by using high-fat diet (HFD)-induced obese mice and a palmitic acid (PA)-treated HepG2 cell line. SEM reduced the body weight gain of obese mice and alleviated related metabolic disorders such as insulin resistance, hyperlipidemia, and systemic inflammation. Furthermore, lipid accumulation in the liver and HepG2 cells was reduced by SEM. SEM downregulated the gene and protein levels of lipogenic regulator factors, and upregulated the gene and protein levels of the regulator factors responsible for lipolysis and fatty acid β-oxidation. Meanwhile, SEM activated AMP-activated protein kinase (AMPK), which might explain the regulatory effect of SEM on fatty acid β-oxidation and lipogenesis. Additionally, the PKA-C and phospho-PKA substrate levels were higher after SEM treatment. Further research found that after pretreatment with the PKA inhibitor, H89, lipid accumulation was increased even with SEM administration in HepG2 cells, and the effect of SEM on lipid metabolism-related regulator factors was abolished by H89. In conclusion, SEM has a positive therapeutic effect on obesity and obesity-related hepatic steatosis by regulating the hepatic lipid metabolism mediated by the PKA pathway.

We determined the seroprevalence of chikungunya virus (CHIKV) infection in the adult resident population in Singapore following local outbreaks of chikungunya fever (CHIKF) in 2008-2009.Our cross-sectional study involved residual sera from 3,293 adults aged 18-79 years who had participated in the National Health Survey in 2010. Sera were tested for IgG antibodies against CHIKV and dengue virus (DENV) and neutralizing antibodies against CHIKV.The prevalence of CHIKV-neutralizing antibodies among Singapore residents aged 18-79 years was 1.9% (95% confidence interval: 1.4%- 2.3%). The CHIKV seroprevalence was highest in the elderly aged 70-79 years at 11.5%, followed by those aged 30-39 years at 3.1%. Men had significantly higher CHIKV seroprevalence than women (2.5% versus 1.3%, p = 0.01). Among the three main ethnic groups, Indians had the highest seroprevalence (3.5%) compared to Chinese (1.6%) and Malays (0.7%) (p = 0.02 and p = 0.01, respectively). Multivariable logistic regression identified adults aged 30-39 years and 70-79 years, men, those of Indian ethnicity and ethnic minority groups, and residence on ground floor of public and private housing apartments as factors that were significantly associated with a higher likelihood of exposure to CHIKV. The overall prevalence of anti-DENV IgG antibodies was 56.8% (95% CI: 55.1%- 58.5%), while 1.5% (95% CI: 1.1%- 2.0%) of adults possessed both neutralizing antibodies against CHIKV and IgG antibodies against DENV.Singapore remains highly susceptible to CHIKV infection. There is a need to maintain a high degree of vigilance through disease surveillance and vector control. Findings from such serological study, when conducted on a regular periodic basis, could supplement surveillance to provide insights on CHIKV circulation in at-risk population.

An oseltamivir-resistant influenza A pandemic (H1N1) 2009 virus evolved and emerged from zero to 52% of detectable virus within 48 hours of a patient’s exposure to oseltamivir. Phylogenetic analysis and data gathered by pyrosequencing and cloning directly on clinical samples suggest that the mutant emerged de novo.

We describe incidence and risk factors for pandemic (H1N1) 2009 virus infection in healthcare personnel during the June–September 2009 epidemic in Singapore. Personnel contributed 3 serologic samples during June–October 2009, with seroconversion defined as a >4-fold increase in hemagglutination inhibition titers to pandemic (H1N1) 2009. Of 531 participants, 35 showed evidence of seroconversion. Seroconversion rates were highest in nurses (28/290) and lowest in allied health staff (2/116). Significant risk factors on multivariate analysis were being a nurse (adjusted odds ratio [aOR] 4.5, 95% confidence interval [CI] 1.0–19.6) and working in pandemic (H1N1) 2009 isolation wards (aOR 4.5, 95% CI 1.3–15.6). Contact with pandemic (H1N1) 2009–infected colleagues (aOR 2.5, 95% CI 0.9–6.6) and larger household size (aOR 1.2, 95% CI 1.0–1.4) were of borderline significance. Our study suggests that seroconversion was associated with occupational and nonoccupational risk factors.

Nanostructures possessing plasmonic and magnetic properties can enhance the transverse magneto-optical Kerr effect (TMOKE) by exciting surface plasmon resonances (SPRs). This provides a promising platform for magneto-optical SPR sensors with significantly improved sensing performance. Here, we propose a high-performance magneto-optical SPR sensor, which consists of a bilayer Au/Co grating placed on a gold film. By tuning the structural parameters, a Fano-like TMOKE spectrum with a linewidth of only 0.0135 nm and an amplitude approaching the theoretical maximum is obtained. We attribute the optimal TMOKE signal achieved by the sensor to the critical coupling concept which is associated with the trade-off between scattering and intrinsic decay rates of the system. The optimized nanostructure sensor demonstrates a sensitivity of 1432 nm/RIU to refractive index fluctuations as small as 0.0001 in air, and all figures of merit (FOM) up to 105 RIU−1, making it suitable for gas sensor fabrication. [ABSTRACT FROM AUTHOR]