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ObjectiveTo propose targeted prevention and control measures， improve product quality， and ensure food safety， Salmonella contamination in the production and processing of prefabricated crispy pork in a large food processing factory was analyzed.MethodsA total of 103 meat samples were collected during the production and processing of prefabricated crispy pork， and 165 environmental samples were collected before processing. Qualitative and quantitative analyses of Salmonella were performed. Finally， serological typing， multilocus sequence typing （MLST）， and pulsed filed gel electrophoresis （PFGE） typing of the isolated Salmonella strains were evaluated.ResultsThe isolation rate of Salmonella from meat samples was 47.6% （49/103）. The isolation rate of Salmonella from environmental samples was 1.2% （2/165）. Fifty-one Salmonella strains were divided into 9 serotypes and 9 STs. Among them， Salmonella enteritidis ST11 was dominant in the production and processing of prefabricated crispy pork， and was detected in the environment. Twenty-two strains of Salmonella enteritidis were divided into 7 PFGE bands， with a similarity of over 92.9%.ConclusionA high overall contamination rate of Salmonella was found in meat samples. Therefore， controlling Salmonella contamination of raw meat is key to improving product quality. The amount of Salmonella contamination in fried products can be effectively controlled. Furthermore， strict separation of processing and storage areas for poultry and stored products is necessary to prevent cross-contamination of microorganisms in food.

The development of electric arc furnace （EAF） short process steelmaking is an important way for the iron and steel industry to realize the goal of "double carbon". In recent years， the modern EAF technology has been developing rapidly， and the bottom-blowing stirring technology of EAF is also progressing and being promoted， which makes an important contribution to the high efficiency and energy saving in production with EAF. This paper summarizes the mechanism， process characteristics， system composition， gas type， bottom blowing element type and process arrangement of the electric arc furnace， and summarizes the application of the bottom blowing technology. Simulation calculations shows that the flow rate of molten steel is obviously low in the area far away from the bottom blowing device. By arranging the bottom blowingdevice and optimizing the volume of bottom blowing gas in conjunction with the furnace characteristics， it is possible to effectively enhance the dynamic conditions of the molten pool， facilitate the mass transfer of elements within the molten steel， thereby achieving the goal of reducing energy and raw material consumption， and enhancing production efficiency.Therefore， it can be inferred that conducting research， combining different techniques such as blowing， power supply andpowder injection， formulating bottom blowing process system according to the characteristics of different new furnaces， as well as realizing intelligent bottom blowing are important directions for the development of short process steelmaking of modern EAF

The experimental process of rebound testing of rubber material was simulated using finite element analysis software ABAQUS, and the energy changes during the rebound process were discussed, laying the foundation for further research on viscoelasticity of rubber materials. The results showed that the characterization results of the new method were basically consistent with the actual test results, proving that the fitted intrinsic equation was consistent with the properties of the material itself, and at the same time characterizing the accurate energy changes during the rebound process. During the impact process, the kinetic energy of the pendulum was mainly transformed into the elastic potential energy and dissipation energy of the specimen. In addition, by analyzing the changes in the temperature field of the sample model, it was more intuitive to observe the temperature rise due to the energy loss during rubber deformation, indicating that part of the lost kinetic energy was converted into thermal energy and dissipated into the environment.

ObjectiveTo understand the contamination and drug resistance characteristics of non-typhoidal Salmonella （NTS） during pig slaughter.MethodsA total of 170 carcasses and environmental samples were collected from two large-scale pig slaughterhouses in May and August 2021 in Shandong Province， China. Whole genome sequencing （WGS） combined with bioinformatics was used to analyze the data of the NTS isolates.ResultsNTS was detected in 29 of 170 pork samples， detection rate was 17.1%. Salmonella typhimurium was the predominant serotype （58.6%， 17/29） in the samples. The results of the drug sensitivity analysis showed that 29 NTS strains had 15 drug resistance spectra， with the highest rate of tetracycline resistance （100.0%， 29/29）， followed by ampicillin and chloramphenicol （79.3%， 23/29）. The multidrug resistance rate was 86.2% （25/29 patients）. Multilocus sequence typing （MLST） showed that ST19 was the main type， accounting for 48.3% （14/29） of cases. Analysis of drug resistance genes showed that they carried mainly tet（A）， tet（B）， tet（M）， blaTEM-1B， blaCMY-97， floR， cmlA1， etc.ConclusionThe phenomenon of NTS contamination exists in some pig slaughterhouses in Shandong Province. NTS has shown resistance to multiple antibiotics， suggesting that attention should be paid to the prevention of NTS in pig slaughterhouses.

ObjectivesThe objective of this study was to develop a predictive nomogram for intermediate-risk differentiated thyroid cancer (DTC) patients after fixed 3.7GBq (100mCi) radioiodine remnant ablation (RRA).MethodsData from 265 patients who underwent total thyroidectomy with central lymph node dissection (CND) and received RRA treatment at a single institution between January 2018 and March 2023 were analyzed. Patients with certain exclusion criteria were excluded. Univariate and multivariate logistic regression analyses were performed to identify risk factors for a non-excellent response (non-ER) to RRA. A nomogram was developed based on the risk factors, and its performance was validated using the Bootstrap method with 1,000 resamplings. A web-based dynamic calculator was developed for convenient application of the nomogram.ResultsThe study included 265 patients with intermediate-risk DTC. Significant differences were found between the ER group and the non-ER group in terms of CLNM>5, Hashimoto’s thyroiditis, sTg level, TgAb level (P < 0.05). CLNM>5 and sTg level were identified as independent risk factors for non-ER in multivariate analysis. The nomogram showed high accuracy, with an area under the curve (AUC) of 0.833 (95% CI = 0.770–0.895). The nomogram’s predicted probabilities aligned closely with actual clinical outcomes.ConclusionsThis study developed a predictive nomogram for intermediate-risk DTC patients after fixed 3.7GBq (100mCi) RRA. The nomogram incorporates CLNM>5 and sTg levels as risk factors for a non-ER response to RRA. The nomogram and web-based calculator can assist in treatment decision-making and improve the precision of prognosis information. Further research and validation are needed.

ObjectiveThis study aimed to clarify the heat inactivation mechanics of Salmonella in commercial crispy meat and provide guidance for its safe consumption by studying the inactivation pattern of Salmonella in crispy meat at different heating temperatures.MethodsThe crispy meat inoculated with 108 CFU/g Salmonella typhimurium was heat treated at 80 ℃， 90 ℃， 100 ℃， 110 ℃， and 120 ℃ for a certain time. The thermal inactivation curves of Salmonella in crispy meat were fitted using a linear model， a Logistic model， and a Weibull model， and the optimal model was verified by external experiments.ResultsThe results showed that compared with the linear model and the Logistic model， the Weibull model was more suitable to describe the thermal inactivation of Salmonella in crispy meat. The judgment coefficient R2 of the primary model was more than 0.992 1， and the R2 of the secondary model was 0.949 2 and 0.995 9， respectively. The accuracy Af and deviation Bf of the model verified at 95 ℃ and 105 ℃ were within the acceptable range， which indicated that the model constructed in this experiment can better describe the inactivation pattern of Salmonella in crispy meat in the temperature range of 80 ℃-120 ℃.ConclusionThis study is expected to guide the safe heating of crispy meat to reduce microbial risk during consumption.

Objectives Hypertension is one of the most important risk factors for cardio-cerebral vascular diseases, which brings a heavy economic burden to society and becomes a major public health problem. At present, the pathogenesis of hypertension is unclear. Increasing evidence has proven that the pathogenesis of hypertension is closely related to the dysbiosis of gut microbiota. We briefly reviewed relevant literature on gut microbiota and hypertension to summarize the relationship between gut microbiota and hypertension, linked the antihypertension effects of drugs with their modulation on gut microbiota, and discussed the potential mechanisms of various gut microbes and their active metabolites to alleviate hypertension, thus providing new research ideas for the development of antihypertension drugs. Methods The relevant literature was collected systematically from scientific database, including Elsevier, PubMed, Web of Science, China National Knowledge Infrastructure (CNKI), Baidu Scholar, as well as other literature sources, such as classic books of herbal medicine. Results Hypertension can lead to gut microbiota imbalance and gut barrier dysfunction, including increased harmful bacteria and hydrogen sulfide and lipopolysaccharide, decreased beneficial bacteria and short-chain fatty acids, decreased intestinal tight junction proteins and increased intestinal permeability. Gut microbiota imbalance is closely related to the occurrence and development of hypertension. At present, the main methods to regulate the gut microbiota include fecal microbiota transplantation, supplementation of probiotics, antibiotics, diet and exercise, antihypertensive drugs, and natural medicines. Conclusions Gut microbiota is closely related to hypertension. Investigating the correlation between gut microbiota and hypertension may help to reveal the pathogenesis of hypertension from the perspective of gut microbiota, which is of great significance for the prevention and treatment of hypertension.

Background There is an issue of mismatch between supply and demand of medical care resources in China. The implementation of contracted family doctor services is an effective measure to address the issue, and to improve the hierarchical diagnosis and treatment system. Therefore, it is urgent to speed up the training and ensure the training quality of general practice workforce. Objective To develop a comprehensive and systematic general practitioner (GP) competency model after analyzing the concept and structural domains of competencies (including inner competencies) required for GPs to deliver contracted healthcare services, providing insights into the realization of training eligible GPs in terms of quantity and quality, and the improvement of quality and efficiency of contracted services. Methods From December 2020 to September 2021, we conducted in-depth, semi-structured interviews with 38 GPs from 10 medical institutions in four cities (Zhenjiang, Taizhou and Suzhou in Jiangsu Province, and Foshan in Guangdong Province) , then treated the interview results applying the three-level coding and theoretical saturation used in the grounded theory. After that, we developed a General Practitioner Competency Model. Results The model consists of 10 items, which belong to four domains: general care capability, humanistic practice capability, team cooperation capability, learning and development capability. General care capability and learning and development capability belong to external competencies, which represent the external performance and driving force of competencies, and determine the level of competencies of GPs to provide contracted services. Humanistic practice capability and team cooperation capability reflect the internal traits and competencies, which belong to the inner competencies, and determine the potential of GPs to provide contracted services. Conclusion The model developed by us is complete and comprehensive, in which the inner competencies of GPs have been fully explored, which may be contributive to the training of GPs delivering contracted services, and to the development of a GP competency assessment system using quantitative empirical methods.

Coronary microvascular dysfunction (CMD) is a high-risk factor for a variety of cardiovascular events. Due to its complex aetiology and concealability, knowledge of the pathophysiological mechanism of CMD is still limited at present, which greatly restricts its clinical diagnosis and treatment. Studies have shown that CMD is closely related to a variety of cardiovascular diseases, can aggravate the occurrence and development of cardiovascular diseases, and is closely related to a poor prognosis in patients with cardiovascular diseases. Improving coronary microvascular remodelling and increasing myocardial perfusion might be promising strategies for the treatment of cardiovascular diseases. In this paper, the pathogenesis and functional assessment of CMD are reviewed first, along with the relationship of CMD with cardiovascular diseases. Then, the latest strategies for the treatment of CMD and cardiovascular diseases are summarized. Finally, urgent scientific problems in CMD and cardiovascular diseases are highlighted and future research directions are proposed to provide prospective insights for the prevention and treatment of CMD and cardiovascular diseases in the future.

Hypertension has become one of the major public health problems in the world. At present, the pathogenesis of hypertension has still not been completely elucidated. In recent years, an increasing evidence shows that intestinal microecology is closely related to hypertension, which provides a new thinking for the prevention and treatment of hypertension. Traditional Chinese medicine (TCM) has unique advantages in the treatment of hypertension. Taking intestinal microecology as the target, it is possible to interpreting the scientific connotation of TCM prevention and treatment of hypertension by updating the treatment concept of hypertension, so as to improve the therapeutic effect. In our study, the clinical evidence for TCM treatment of hypertension was systematicly summarized. And the relationship among TCM, intestinal microecology and hypertension was analyzed. In addition, the methods by which TCM regulates intestinal microecology to prevent and treat hypertension were presented, to provide new research ideas for prevention and treatment of hypertension.

Objectives: This study aims to examine and explain the differences at city level in cumulative COVID-19 cases and time from first to last infection during the first 6 weeks of the epidemic in China. Methods: A quantitative study is conducted in China based on the multisource spatial data of 315 Chinese cities. Firstly, the spatial discrepancy of COVID-19 transmission was examined based on spatial autocorrelation analysis and hot pot analysis. Next, a comprehensive indicator framework was established by including a wide range of factors such as human mobility, geographical features, public health measures, and residents’ awareness. Finally, multivariate regression models using these variables were constructed to identify the determinants of COVID-19 transmission. Results: Significant spatial discrepancy of transmission was proved, and 10 determinants were identified. Conclusions: The transmission consequence (measured by the number of cumulative cases) was mostly correlated with the migration scale from Wuhan, followed by socioeconomic factors. Transmission duration (measured as the time from the first to last case within the city) was mostly determined by total migration scale and lockdown speed, which suggests that timely implementation of public health measures facilitated fast control of transmission. Residents’ attention to COVID-19 was proved to be not only helpful for reducing confirmed cases, but also in favor of rapid transmission control. Altitude produced slight but significant effect on transmission duration. These conclusions are expected to provide decision support for the local governments of China and other jurisdictions.

Objective To observe the clinical significance of miR-135b-5p in oral squamous cell carcinoma (OSCC) tissues and to conduct a bioinformatics analysis of its predicted target genes. Methods The expression levels of miR-135b-5p in OSCC tissues and adjacent normal tissues were compared using data from TCGA and GEO databases, and the correlations of miR-135b-5p expression level with clinicopathologic characteristics were analyzed. Fresh tissues were collected in the clinic, and the expression of miR-135b-5p was verified by quantitative real-time PCR. The target genes with enriched pathways were analyzed by using bioinformatics methods. A protein-protein interaction network was constructed to screen hub genes. Results The expression levels of miR-135b-5p were significantly upregulated in OSCC tissues compared to adjacent normal tissues (P < 0.001) and had a good diagnostic capability (AUC=0.960, P < 0.001). The expression level of miR-135b-5p was positively correlated with histopathological grading (P=0.011). Enrichment analyses revealed that the target genes of miR-135b-5p were significantly associated with tumor-related signaling pathways, such as the calcium signaling pathway, the cGMP-PKG signaling pathway and the cAMP signaling pathway. Ten core target genes were obtained by screening: DLG2, ANK3, ERBB4, SCN2B, NBEA, GABRB2, ATP2B2, SNTA1, CACNA1D, and SPTBN4. Conclusion miR-135b-5p may act as an oncogene miRNA in OSCC and has the potential value of acting as a diagnostic biomarker and therapeutic target for OSCC.

The emergence of big data is breaking the spatial and time limitations of urban waterlogging scenario description. The scenario data of different dimensions (e.g., administrative levels, sectors, granularities, and time) have become highly integrated. Accordingly, a structural and systematic model is needed to represent waterlogging scenarios for more efficient waterlogging response decision-making. In this article, a full-view urban waterlogging scenario is first defined and described from four dimensions. Next a structured representation of scenario element is given based on knowledge unit method. The full-view scenario model is then constructed by extracting the scenario correlation structures between different dimensions (called scenario nesting), i.e., inheritance nesting, feedback nesting, aggregation nesting, and selection nesting. Finally, a real-world case study in Wuhan East Lake High-tech Development Zone, China is evaluated to verify the reasonability of the full-view model. The results show that the proposed model effectively integrates scenario data from different dimensions, which helps generate the complete key scenario information for urban waterlogging decision-making. The full-view scenario model is expected to be applicable for other disasters under big data environment.

Coronary microvascular disease (CMVD) is common in patients with cardiovascular risk factors and is associated with an increased risk of adverse cardiovascular events. Although the study of CMVD in modern medicine is ongoing, there is still no effective treatment for it. Traditional Chinese medicine (TCM) has some clinical advantages based on syndrome differentiation and individualized treatment. In this review, we review the clinical significance, pathogenesis, and current treatments of CMVD and systematically summarize the clinical efficacy and potential action mechanisms of TCM for CMVD. In addition, the scientific problems that need to be solved urgently and the research strategy of TCM for CMVD are described. CMVD has great clinical significance, but there are still many gaps in the related research. This review aims to attract the attention of clinicians to CMVD and promote research on CMVD in TCM.

Coronavirus disease 2019 (COVID-19) is an acute respiratory infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and it has become a public health concern worldwide. In addition to respiratory symptoms, some COVID‑19 patients also show various gastrointestinal symptoms and even consider gastrointestinal symptoms to be the first manifestation. A large amount of evidence has shown that SARS-CoV-2 infection could disrupt the gut microbiota balance, and disorders of the gut microbiota could aggravate the condition of COVID-19 patients. Therefore, maintaining the gut microbiota balance is expected to become a potential new therapeutic target for treating COVID-19. Traditional Chinese medicine (TCM) has significant effects in all stages of the prevention and treatment of COVID-19. It can adjust the gut microbiota and is an ideal intestinal microecological regulator. This review summarizes the advantages and clinical efficacy of TCM in the treatment of COVID-19 and expounds on the relationship between TCM and the gut microbiota, the relationship between COVID-19 and the gut microbiota, the mechanism of gut microbiota disorders induced by SARS-CoV-2, the relationship between cytokine storms and the gut microbiota, and the role and mechanism of TCM in preventing and treating COVID-19 by regulating the gut microbiota to provide new research ideas for TCM in the prevention and treatment of COVID-19.

Background: Heart failure as an important issue in global public health, has brought a heavy economic burden. Traditional Chinese medicine injections (TCMIs) have significant effects on heart failure with reduced ejection fraction (HFrEF). However, it is difficult for clinicians to identify the differences in clinical efficacy and safety of various TCMIs. The purpose of this study is to compare the efficacy and safety of various TCMIs for treating HFrEF by conducting a Bayesian network meta-analysis (NMA) and to further provide references for clinical decision-making.Methods: The clinical randomized controlled trials of TCMIs for treating HFrEF were searched in seven database from inception to August 3rd, 2021. The Cochrane collaboration’s tool was used to assess the risk of bias. NMA was performed in a Bayesian hierarchical framework. The surface under the cumulative ranking curve (SUCRA), the multi-dimensional efficacy analysis, the comparison-adjusted funnel plot, and the node-splitting analysis were conducted using R software.Results: A total of 107 eligible RCTs involving 9,073 HFrEF patients and 6 TCMIs were included. TCMIs include Huangqi injection (HQ) also called Astragalus injection, Shenfu injection (SF), Shengmai injection (SGM), Shenmai injection (SM), Xinmailong injection (XML), and Yiqifumai lyophilized injection (YQFM). The results of NMA and SUCRA showed that with conventional treatment (CT) as a common control, in terms of clinical efficacy, CT + XML was most effective in New York Heart Association cardiac functional classification efficiency, brain natriuretic peptide, and N-terminal pro-brain natriuretic peptide; the CT + SM was most effective in 6-min walking test, left ventricular end-diastolic diameter, left ventricular end-systolic diameter and cardiac output; the CT + YQFM was most effective in left ventricular ejection fraction; the CT + HQ was most effective in stroke volume; the CT + SF was most effective in Minnesota Living with Heart Failure Questionnaire. In terms of safety, there was no significant difference between CT + TCMIs and CT.Conclusion: This Bayesian network meta-analysis results show that the combination of qualified TCMIs and CT is more effective for HFrEF patients than CT alone, and CT + XML and CT + SM may be one of the potential optimal treatments. Also, the safety of these TCMIs needs to be further observed. However, due to some limitations, the conclusions need to be verified by more large-sample, double-blind, multi-center RCTs.

Coronavirus disease 2019 (COVID-19) is an emergent infectious pneumonia caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is highly contagious and pathogenic. COVID-19 has rapidly swept across the world since it was first discovered in December 2019 and has drawn significant attention worldwide. During the early stages of the outbreak in China, traditional Chinese medicines (TCMs) were involved in the whole treatment process. As an indispensable part of TCM, Chinese patent medicines (CPMs) played an irreplaceable role in the prevention and treatment of this epidemic. Their use has achieved remarkable therapeutic efficacy during the period of medical observation and clinical treatment of mild, moderate, severe, and critical cases and during convalescence. In order to better propagate and make full use of the benefits of TCM in the treatment of COVID-19, this review will summarize the potential target of SARS-CoV-2 as well as the theoretical basis and clinical efficacy of recommended 22 CPMs by the National Health Commission and the Administration of TCM and local provinces or cities in the treatment of COVID-19. Additionally, the study will further analyze the drug composition, potential active ingredients, potential targets, regulated signaling pathways, and possible mechanisms for COVID-19 through anti-inflammatory and immunoregulation, antiviral, improve lung injury, antipyretic and organ protection to provide meaningful information about the clinical application of CPMs.

Transformer insulation paper is a key indicator for transformer remaining operational life. Paper decomposition is evaluated using the degree of polymerization (DP) which calls for samples of insulation paper from operating transformers. Since collecting such paper samples is extremely difficult, other indicators have been used to indirectly reveal the DP value of insulation paper. This includes dissolved gases in transformer oil such as carbon oxides and hydrocarbon gases, furan compounds, methanol, ethanol, and moisture along with some oil characteristics such as interfacial tension. However, for the same oil sample, these individual parameters lead to different DP values. This is attributed to the lack of accuracy of the established mathematical and artificial intelligence models correlating DP with each of the above mentioned individual parameters. This paper presents a self-learning method to estimate the DP value of transformer insulation paper based on multiple transformer oil aging parameters. The proposed method comprises data processing, fuzzy c-means and linear regression. Results reveal that estimating the DP value based on multiple aging parameters is more accurate than estimating it using one single parameter as per the current practice. The proposed method not only helps to understand the correlation between multiple oil aging parameters and the DP value of paper insulation, but also promotes the establishment of more accurate life assessment models for power transformers based on these oil aging parameters.

Distributed optical fiber vibration sensing (DVS) can measure vibration information along with an optical fiber. Accurate classification of vibration events is a key issue in practical applications of DVS. In this paper, we propose a convolutional neural network (CNN) to analyze DVS data and achieve high-accuracy event recognition fully. We conducted experiments outdoors and collected more than 10,000 sets of vibration data. Through training, the CNN acquired the features of the raw DVS data and achieved the accurate classification of multiple vibration events. The recognition accuracy reached 99.9% based on the time–space data, a higher than used time-domain, frequency–domain, and time–frequency domain data. Moreover, considering that the performance of the DVS and the testing environment would change over time, we experimented again after one week to verify the method’s generalization performance. The classification accuracy using the previously trained CNN is 99.2%, which is of great value in practical applications.

According to the requirement of IGBT's over-current turn-off capability, this paper analyzes the factors affecting the dynamic latch-up of IGBT chip during the over-current turn-off process, including the gate width of IGBT cell, the doping concentration of back P + collector and the dVce/dt when the IGBT is turned off. The simulation results show that the anti-dynamic latch-up capability of IGBT can be effectively improved by decreasing the gate width and back P + collector doping concentration. Through multi-cell parallel simulation, it is found that current concentration exists in the process of overcurrent trun-off, which leads to the further increase of the lattice temperature, and the overcurrent turn-off capability declines.

In this paper, a 4500V IGBT is investigated by device simulation. The substrate resistivity and thickness of 4500V IGBT are determined by simulation, and the appropriate implantation dose of field stop layer is determined by the simulation. The test results show that the device can not meet the application requirements of power system, so we optimize the key parameters such as saturation voltage and safe operating area. The optimized device was fabricated and the experimental results show that the breakdown voltage is 6110V, the saturation voltage is 2.6V, and the maximum controllable turn-off current is 160A, which can well meet the simulation expectation and application requirements of power system.

Abstract Background Osseointegration depends on the implant surface, bone quality and the local and systemic host environment, which can differ in male and female patients. This study was undertaken in order to determine if male and female cells respond differently to titanium surfaces that have micron-scale roughness and if interactions of calciotropic hormones [1α,25(OH)2D3 and 17β-oestradiol (E2)] and microstructured surfaces on osteoblasts are sex dependent. Methods Osteoblasts from 6-week old Sprague-Dawley rats were cultured on tissue culture polystyrene (TCPS) or on titanium (Ti) disks with two different surface topographies, a smooth pretreated (PT) surface and a coarse grit-blasted/acid-etched (SLA) surface, and treated with 1α,25(OH)2D3, E2, or E2 conjugated to bovine serum albumin (E2-BSA). Results Male and female cells responded similarly to Ti microstructure with respect to cell number and levels of osteocalcin, transforming growth factor-β1, osteoprotegerin and prostaglandin E2 in their conditioned media, exhibiting a more differentiated phenotype on SLA than on PT or TCPS. E2 and E2-BSA increased differentiation and local factor production, an effect that was microstructure dependent and found only in female osteoblasts. 1α,25(OH)2D3 increased osteoblast differentiation and local factor production in female and male cells, but the effect was more robust in male cells. Conclusions Male and female rat osteoblasts respond similarly to surface microstructure but exhibit sexual dimorphism in substrate-dependent responses to systemic hormones. Oestrogen affected only female cells while 1α,25(OH)2D3 had a greater effect on male cells. These results suggest that successful osseointegration in males and females may depend on the implant surface design and correct levels of calciotropic hormones.

Abstract Background Shigella flexneri is a gram-negative, facultative pathogen that causes the majority of communicable bacterial dysenteries in developing countries. The virulence factors of S. flexneri have been shown to be produced at 37 degrees C but not at 30 degrees C. To discover potential, novel virulence-related proteins of S. flexneri, we performed differential in-gel electrophoresis (DIGE) analysis to measure changes in the expression profile that are induced by a temperature increase. Results The ArgT protein was dramatically down-regulated at 37 degrees C. In contrast, the ArgT from the non-pathogenic E. coli did not show this differential expression as in S. flexneri, which suggested that argT might be a potential anti-virulence gene. Competitive invasion assays in HeLa cells and in BALB/c mice with argT mutants were performed, and the results indicated that the over-expression of ArgTY225D would attenuate the virulence of S. flexneri. A comparative proteomic analysis was subsequently performed to investigate the effects of ArgT in S. flexneri at the molecular level. We show that HtrA is differentially expressed among different derivative strains. Conclusion Gene argT is a novel anti-virulence gene that may interfere with the virulence of S. flexneri via the transport of specific amino acids or by affecting the expression of the virulence factor, HtrA.

Abstract Background The effects of enterolignans, e.g., enterodiol (END) and particularly its oxidation product, enterolactone (ENL), on prevention of hormone-dependent diseases, such as osteoporosis, cardiovascular diseases, hyperlipemia, breast cancer, colon cancer, prostate cancer and menopausal syndrome, have attracted much attention. To date, the main way to obtain END and ENL is chemical synthesis, which is expensive and inevitably leads to environmental pollution. To explore a more economic and eco-friendly production method, we explored biotransformation of enterolignans from precursors contained in defatted flaxseeds by human intestinal bacteria. Results We cultured fecal specimens from healthy young adults in media containing defatted flaxseeds and detected END from the culture supernatant. Following selection through successive subcultures of the fecal microbiota with defatted flaxseeds as the only carbon source, we obtained a bacterial consortium, designated as END-49, which contained the smallest number of bacterial types still capable of metabolizing defatted flaxseeds to produce END. Based on analysis with pulsed field gel electrophoresis, END-49 was found to consist of five genomically distinct bacterial lineages, designated Group I-V, with Group I strains dominating the culture. None of the individual Group I-V strains produced END, demonstrating that the biotransformation of substrates in defatted flaxseeds into END is a joint work by different members of the END-49 bacterial consortium. Interestingly, Group I strains produced secoisolariciresinol, an important intermediate of END production; 16S rRNA analysis of one Group I strain established its close relatedness with Klebsiella. Genomic analysis is under way to identify all members in END-49 involved in the biotransformation and the actual pathway leading to END-production. Conclusion Biotransformation is a very economic, efficient and environmentally friendly way of mass-producing enterodiol from defatted flaxseeds.