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To reduce the content of free gossypol in cottonseed meal and improve the quality of cottonseed protein, this study used a two-stage fermentation method to treat cottonseed meal. Enterococcus faecalis (E) was first added, and then Aspergillus oryzae (M1) was added for staged fermentation. The fermentation conditions of mixed were optimized by single factor and orthogonal experiments. The results showed that when the inoculation amount of Enterococcus faecium was 1.5%, the fermentation temperature was 37 ℃, the fermentation time was 24 h, the inoculation amount of Aspergillus oryzae was 1.5%, the fermentation temperature was 30 ℃, the fermentation time 96 h, and the initial fermentation moisture of cottonseed meal was 50%, the crude protein content of cottonseed meal increased from 39.6% to 49.64%, the acid-soluble protein content increased from 4.79% to 36.58%, and the free gossypol content decreased from 1370 mg/kg to 45.32 mg/kg, and the detoxification rate reached 96.7%. The results would provide a scientific basis for the high-value utilization of cottonseed meal.

Abstract Background The efficacy of anti-PD-1 therapy is primarily hindered by the limited T-cell immune response rate and immune evasion capacity of tumor cells. Autophagy-related protein 7 (ATG7) plays an important role in autophagy and it has been linked to cancer. However, the role of ATG7 in the effect of immune checkpoint blockade (ICB) treatment on high microsatellite instability (MSI-H)/mismatch repair deficiency (dMMR) CRC is still poorly understood. Methods In this study, patients from the cancer genome altas (TCGA) COAD/READ cohorts were used to investigate the biological mechanism driving ATG7 development. Several assays were conducted including the colony formation, cell viability, qRT-PCR, western blot, immunofluorescence, flow cytometry, ELISA, immunohistochemistry staining and in vivo tumorigenicity tests. Results We found that ATG7 plays a crucial role in MSI-H CRC. Its knockdown decreased tumor growth and caused an infiltration of CD8+ T effector cells in vivo. ATG7 inhibition restored surface major histocompatibility complex I (MHC-I) levels, causing improved antigen presentation and anti-tumor T cell response by activating reactive oxygen species (ROS)/NF-κB pathway. Meanwhile, ATG7 inhibition also suppressed cholesterol accumulation and augmentation of anti-tumor immune responses. Combining ATG7 inhibition and statins improved the therapeutic benefit of anti-PD-1 in MSI-H CRC. Importantly, CRC patients with high expression of both ATG7 and recombinant 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR) experienced worse prognosis compared to those with low ATG7 and HMGCR expression. Conclusions Inhibition of ATG7 leads to upregulation of MHC-I expression, augments immune response and suppresses cholesterol accumulation. These findings demonstrate that ATG7 inhibition has therapeutic potential and application of statins can increase the sensitivity to immune checkpoint inhibitors.

Investigating the formation mechanisms of carbonate geothermal reservoirs is of theoretical and practical significance for summarizing the formation pattern of geothermal resources and further guiding their effective exploitation. The Beijing-Tianjin-Hebei Plain (BTHP), predominantly located within the Jizhong Depression and Cangxian Uplift in the Bohai Bay Basin, serves as the primary region for geothermal exploitation and utilization in China. More than 1500 geothermal wells have been drilled therein, with water temperature at the wellhead ranging from 55 to 110 °C, single-well flow rate ranging between 80 and 120 m3/h, and cumulative heating area exceeding 100 × 106 m3. However, the exploration and research in the region remain limited overall. As per the previous geothermal and petroleum exploration results and the latest geothermal drilling data, this study comprehensively evaluated the geothermal resources of karst geothermal reservoirs. The results show that two suites of carbonate karst reservoirs, namely the Jxw Formation and the Ordovician strata, have primarily developed in the BTHP, and their formation and evolution can be divided into four stages: the Mesoproterozoic-Early Paleozoic stage with carbonate sedimentation and the development of interlayer karst, the Late Paleozoic stage with the development of direct sedimentary cover, the Mesozoic stage with compressional uplifting and development of buried hill karst, and the Cenozoic stage with regional cover deposition and the modification and finalization of karst geothermal reservoirs. Accordingly, the porosity evolution history of the geothermal reservoirs is composed of three stages, namely a significant decrease followed by a minor increase, a gradual decline, and then a small fluctuation from increase to decrease before slowly rising again. The karstification in geothermal reservoirs can be summarized into quasi-syngenetic karstification, epigenetic karstification, and burial karstification, which can be subdivided into seven subcategories. The carbonate geothermal reservoirs in the study area boast total geothermal resources of 53.821 × 109 GJ, or 184.155 × 109 t of standard coal equivalent (tce), and the annual exploitable geothermal resources in the urban area can heat an area of (400‒500) × 106 m3, indicating great potential of geothermal exploitation.

As the world’s fourth most deadly cancer, colorectal cancer (CRC) still needed the novel therapeutic drugs and target urgently. Although cyclin-dependent kinase 12 (CDK12) has been shown to be implicated in the malignancy of several types of cancer, its functional role and mechanism in CRC remain largely unknown. Here, we found that suppression of CDK12 inhibited tumor growth in CRC by inducing apoptosis. And CDK12 inhibition triggered autophagy by upregulating autophagy related gene 7 (ATG7) expression. Inhibition of autophagy by ATG7 knockdown and chloroquine (CQ) further decreased cell viability induced by CDK12 inhibition. Further mechanism exploration showed that CDK12 interacted with protein kinase B (AKT) regulated autophagy via AKT/forkhead box O3 (AKT/FOXO3) pathway. FOXO3 transcriptionally upregulated ATG7 expression and autophagy when CDK12 inhibition in CRC. Level of CDK12 and p-FOXO3/FOXO3 ratio were correlated with survival in CRC patients. Moreover, CDK12 inhibition improved the efficacy of anti-programmed cell death 1(PD-1) therapy in CRC murine models by enhancing CD8 + T cells infiltration. Thus, our study founded that CDK12 inhibition upregulates ATG7 triggering autophagy via AKT/FOXO3 pathway and enhances anti-PD-1 efficacy in CRC. We revealed the roles of CDK12/FOXO3/ATG7 in regulating CRC progression, suggesting potential biomarkers and therapeutic target for CRC.

In recent years, the advancement of photovoltaic power generation technology has led to a surge in the construction of photovoltaic power stations in desert gravel areas. However, traditional equal cross-section photovoltaic bracket pile foundations require improvements to adapt to the unique challenges of these environments. This paper introduces a new type of photovoltaic bracket pile foundation named the “serpentine pile foundation” based on the principle of biomimicry. Utilizing experimental data, numerical simulation technology was employed to comprehensively investigate the pullout resistance, compressive resistance, and horizontal bearing performance of the serpentine pile foundation. Comparative analysis with traditional square and circular pile foundations revealed the serpentine pile foundation’s significant advantages in all performance indexes. The serpentine pile exhibits a significantly higher ultimate uplift bearing capacity of 70.25 kN, which is 8.56 times that of the square pile and 10.94 times that of the circular pile. This study not only offers valuable technical support for the construction of photovoltaic power plants in desert gravel areas but also holds great significance in advancing the sustainable development of the global photovoltaic industry.

Abstract Background Surgical site infection (SSI) is a common complication following craniotomy that increases morbidity, mortality, and medical expenses. The objectives of this study were to determine the relevant risk factors associated with SSI after elective craniotomy for brain tumor and analyse the treatments for SSI. Methods A retrospective nested case‒control study was conducted using data from patients who underwent craniotomy for brain tumor resection at the Neurosurgical Oncology Department No. 6 of Beijing Tiantan Hospital, Capital Medical University, between January 2019 and December 2021. Risk factors for SSI were determined using multivariate logistic regression analysis. We analyzed microbiological and related treatment data for different SSI types. Results Among 2061 patients who underwent craniotomy for brain tumor, 31 had SSI (1.50%). In the multivariate logistic regression analysis, body mass index (BMI) and operative duration were identified as independent risk factors for SSI. The most common microorganism isolated from SSIs was Staphylococcus epidermidis (22.9%), and drug sensitivity results showed that gram-positive bacteria were sensitive to linezolid, vancomycin and tigecycline, whereas gram-negative bacteria were sensitive to meropenem, cefepime and ceftazidime. Six of the seven patients who underwent bone flap removal due to osteomyelitis were infected with gram-negative bacteria. Conclusions BMI and operative duration were identified as independent risk factors for SSI. Diabetes mellitus, previous ratio therapy, type of incision, recurrence tumor and other risk factors were not found to be associated with the occurrence of SSI in this study.

Abstract High-temperature hydrothermal systems are mainly distributed in the north–south graben systems of southern Tibet as an important part of the Mediterranean–Tethys Himalayan geothermal belt in mainland China. As the largest unit capacity and second stable operating geothermal power station in China, Yangyi is the fracture-controlled type geothermal field in the center of Yadong–Gulu Graben. In this paper, hydrogeological and hydrochemical characteristics, isotope composition (δD and δ18O, 87Sr/86Sr and δ11B) of borehole water, hot springs, and surface river samples were analyzed. From the conservative elements (such as Cl− and Li+) and δD and δ18O values, the geothermal water of the Yangyi high-temperature geothermal field is estimated to be of meteoric origin with the contributions of chemical components of the magmatic fluid, which is provided by partially molten granite as a shallow magmatic heat source. According to logging data, the geothermal gradient and terrestrial heat flow value of the Yangyi high-temperature geothermal field are 6.48 ℃/100 m and 158.37 mW m−2, respectively. Combining the hydrothermal tracer experiment, 87Sr/86Sr and δ11B ratios obtained with gradually decreasing reservoir temperatures from the Bujiemu stream geothermal zone to Qialagai stream geothermal zone, we suggested the deep geothermal waters were mixed with local cold groundwater and then flow northeastward, forming the shallow reservoir within the crushed zone and intersect spot of faults in the Himalayan granitoid. Furthermore, in the process of ascent, the geothermal water is enriched in K+, Na+, and HCO3 − during the interaction with underlying Himalayan granitoid and pyroclastic rocks that occur as wall rocks. The detailed description and extensive discussion are of great significance for the further exploitation and utilization of north–south trending geothermal belts in Tibet.

BackgroundAs a tonal language, Mandarin Chinese has the following pronunciation elements for each syllable: the vowel, consonant, tone, duration, and intensity. Revealing the characteristics of auditory-related cortical processing of these different pronunciation elements is interesting.MethodsA Mandarin pronunciation multifeature paradigm was designed, during which a standard stimulus and five different phonemic deviant stimuli were presented. The electroencephalogram (EEG) data were recorded with 256-electrode high-density EEG equipment. Time-domain and source localization analyses were conducted to demonstrate waveform characteristics and locate the sources of the cortical processing of mismatch negativity (MMN) and P3a components following different stimuli.ResultsVowel and consonant differences elicited distinct MMN and P3a components, but tone and duration differences did not. Intensity differences elicited distinct MMN components but not P3a components. For MMN and P3a components, the activated cortical areas were mainly in the frontal-temporal lobe. However, the regions and intensities of the cortical activation were significantly different among the components for the various deviant stimuli. The activated cortical areas of the MMN and P3a components elicited by vowels and consonants seemed to be larger and show more intense activation.ConclusionThe auditory processing centers use different auditory-related cognitive resources when processing different Mandarin pronunciation elements. Vowels and consonants carry more information for speech comprehension; moreover, more neurons in the cortex may be involved in the recognition and cognitive processing of these elements.

Carbon dots (CDs) have photoconversion performance and have a wide range of applications in agriculture. However, the solution of CDs is susceptible to quench under evaporation of sunlight and is easy to run-off when influenced by the external environment. Here, PVA-coated CDs were used to overcome the solid-state quenching and to prepare CDs microcapsules-polyurethane Film for plant cultivation. In this work, CDs microcapsules which can convert ultraviolet light into blue light for plant growth, were prepared by the “water/oil/water” method, and light-converting CDs microcapsules polyurethane film (CMPF) was prepared by doping CDs microcapsules with polyurethane. The study showed that polyurethane film has good mechanical properties and self-healing ability, the CMPF was able to effectively promote the growth of lettuce, and the effect was most significant at the CDs microcapsules concentration of 4000 mg/L. Compared with the blank group, the fresh and dry weights were increased by 177 % and 143.5 %, respectively, and the content of chlorophyll a, chlorophyll b, carotenoids, and soluble protein were increased by 14.5 %, 188.5 %, 43.3 %, and 17.9 %, respectively. Application of CDs to modulate plant lighting growth regulators for efficient use of ultraviolet (UV) light.

Fluorescent nanomaterials (NMs) are widely used in imaging techniques in biomedical research. Especially in bioimaging systems, with the rapid development of imaging nanotechnology, precious metal clusters such as Au, Ag, and Cu NMs have emerged with different functional agents for biomedical applications. Compared with traditional fluorescent molecules, precious metal clusters have the advantages of high optical stability, easy regulation of shape and size, and multifunctionalization. In addition, NMs possess strong photoluminescent properties with good photostability, high release rate, and sub-nanometer size. They could be treated as fundamental agents in bioimaging usability. This review summarizes the recent advances in bioimaging utilization, it conveys that metal clusters refer to Au, Ag, and Cu fluorescent clusters and could provide a generalized overview of their full applications. It includes optical property measurement, precious metal clusters in bioimaging systems, and a rare earth element-doped heterogeneous structure illustrated in biomedical imaging with specific examples, that provide new and innovative ideas for fluorescent NMs in the field of bioimaging usability.

BackgroundLower-grade glioma (LGG) is a primary intracranial tumor that carry a high risk of malignant transformation and limited therapeutic options. Emerging evidence indicates that the tumor microenvironment (TME) is a superior predictor for tumor progression and therapy response. PLEKHA4 has been demonstrated to be a biomarker for LGG that correlate with immune infiltration. However, the fundamental mechanism by which PLEKHA4 contributes to LGG is still poorly understood.MethodsMultiple bioinformatic tools, including Tumor Immune Estimation Resource (TIMER), Gene Expression Profiling Interactive Analysis (GEPIA2), Shiny Methylation Analysis Resource Tool (SMART), etc., were incorporated to analyze the PLEKHA4. ESTIMATE, ssGSEA, CIBERSORT, TIDE and CellMiner algorithms were employed to determine the association of PLEKHA4 with TME, immunotherapy response and drug sensitivities. Immunohistochemistry (IHC)-based tissue microarrays and M2 macrophage infiltration assay were conducted to verify their associations.ResultsPLEKHA4 expression was found to be dramatically upregulated and strongly associated with unfavorable overall survival (OS) and disease-specific survival (DSS) in LGG patients, as well as their poor clinicopathological characteristics. Cox regression analysis identified that PLEKHA4 was an independent prognostic factor. Methylation analysis revealed that DNA methylation correlates with PLEKHA4 expression and indicates a better outcome in LGG. Moreover, PLEKHA4 was remarkably correlated with immune responses and TME remodeling, as evidenced by its positive correlation with particular immune marker subsets and the putative infiltration of immune cells. Surprisingly, the proportion of M2 macrophages in TME was strikingly higher than others, inferring that PLEKHA4 may regulate the infiltration and polarization of M2 macrophages. Evidence provided by IHC-based tissue microarrays and M2 macrophage infiltration assay further validated our findings. Moreover, PLEKHA4 expression was found to be significantly correlated with chemokines, interleukins, and their receptors, further supporting the critical role of PLEKHA4 in reshaping the TME. Additionally, we found that PLEKHA4 expression was closely associated with drug sensitivities and immunotherapy responses, indicating that PLEKHA4 expression also had potential clinical significance in guiding immunotherapy and chemotherapy in LGG.ConclusionPLEKHA4 plays a pivotal role in reshaping the TME of LGG patients, and may serve as a potential predictor for LGG prognosis and therapy.

Objectives: The mechanism of olfactory disorder (OD) in patients with COVID-19 is unclear. Our study aimed to elucidate the relationships between inflammatory factors and OD in a sample of patients infected with the Omicron variant, with a high vaccination rate in China. Methods: The Sniffin’ Sticks 12-item test was performed in a cross-sectional study of 148 recovered patients who were infected with the Omicron variant to evaluate OD severity. We compared demographic, laboratory, and clinical data. Results: A total of 148 patients infected with the Omicron variant were enrolled. A total of 129 cases of OD were detected. Increased inflammation contributed to OD severity, especially in the adult group. OD was shown to be aggravated by an increase in interleukin-6 levels. The adjusted odds ratio (OR) was 2.22 (95% confidence interval 0.98-5.05, P = 0.056) after adjustment for age, sex, and vaccine characteristics. Conclusion: These findings indicated that the prevalence of OD remains high in vaccinated patients infected with the Omicron variant and that the Sniffin’ Sticks 12-item test might be a feasible method to screen for OD. Interleukin-6 may play a role in the biochemical and pathological processes underlying OD.

Local drug delivery has received increasing attention in recent years. However, the therapeutic efficacy of local delivery of drugs is still limited under certain scenarios, such as in the oral cavity or in wound beds after resection of tumors. In this study, we introduce a bioinspired adhesive hydrogel derived from the skin secretions of Andrias davidianus (SSAD) as a wound dressing for localized drug elution. The hydrogel was loaded with aminoguanidine or doxorubicin, and its controlled drug release and healing-promoting properties were verified in a diabetic rat palatal mucosal defect model and a C57BL/6 mouse melanoma-bearing model, respectively. The results showed that SSAD hydrogels with different pore sizes could release drugs in a controllable manner and accelerate wound healing. Transcriptome analyses of the palatal mucosa suggested that SSAD could significantly upregulate pathways linked to cell adhesion and extracellular matrix deposition and had the ability to recruit keratinocyte stem cells to defect sites. Taken together, these findings indicate that property-controllable SSAD hydrogels could be a promising biofunctional wound dressing for local drug delivery and promotion of wound healing.

Although the involvement of the ubiquitin-proteasome system (UPS) in several coronavirus-productive infections has been reported, whether the UPS is required for infectious bronchitis virus (IBV) and porcine epidemic diarrhea virus (PEDV) infections is unclear. In this study, the role of UPS in the IBV and PEDV life cycles was investigated. When the UPS was suppressed by pharmacological inhibition at the early infection stage, IBV and PEDV infectivity were severely impaired. Further study showed that inhibition of UPS did not change the internalization of virus particles; however, by using R18 and DiOC-labeled virus particles, we found that inhibition of UPS prevented the IBV and PEDV membrane fusion with late endosomes or lysosomes. In addition, proteasome inhibitors blocked the degradation of the incoming viral protein N, suggesting the uncoating process and genomic RNA release were suppressed. Subsequently, the initial translation of genomic RNA was blocked. Thus, UPS may target the virus-cellular membrane fusion to facilitate the release of incoming viruses from late endosomes or lysosomes, subsequently blocking the following virus uncoating, initial translation, and replication events. Similar to the observation of proteasome inhibitors, ubiquitin-activating enzyme E1 inhibitor PYR-41 also impaired the entry of IBV, enhanced the accumulation of ubiquitinated proteins, and depleted mono-ubiquitin. In all, this study reveals an important role of UPS in coronavirus entry by preventing membrane fusion and identifies UPS as a potential target for developing antiviral therapies for coronavirus.

The blast loading direction and in-situ stress field have an effect on the destruction process in the surrounding rock around the tunnel. Five blasting directions are considered in the experiment and simulation. The static stress distribution by confining pressure and the superposition stress waves process are discussed by simulation in LS-DYNA. Results indicated that the hoop stress accelerates the radial cracks growing, and the damage around the hole is not influenced by the blasting direction. The stress wave superposition and failure process along the tunnel are affected by the blasting direction. The distribution of static prestress is symmetrical under the uniform confining pressure (k = 1) and decelerates the crack extension by confining pressure. Under the non-uniform confining pressure loading (k ≠ 1), the tensile prestress is formed with a k increase and accelerates the horizontal crack propagation after blast loading. The concentrated stress is serious in the partial region along the tunnel, especially in the vault position under the static-dynamic coupling loading. Notably, the horizontal destruction area between the hole and the tunnel further expands when k increases.

Abstract Background There is limited information about the types of recreational drugs used by men who have sex with men (MSM) in China or the consequent impact on sexual health and human immunodeficiency virus (HIV) acquisition. Methods We recruited MSM from seven cities in China between 2012 and 2013 using multiple approaches including advertisements on gay websites, collaborating with local MSM community-based organizations, peer referrals, and venues such as gay bars and bathrooms visited by MSM. We divided participants into four subgroups based on the number of recreational drugs (RDs) used in the previous 6 months. We defined use of multiple RDs as use of ≥2 types of RDs. Demographics and HIV-related high-risk behaviors were collected, and blood samples were tested for recent HIV infection by the HIV-1 subtypes B, E, and D immunoglobulin G capture enzyme immunoassay (BED-CEIA). We used multivariable logistic regression adjusted for sociodemographics to determine the adjusted odds ratios (aORs) and associated 95% confidence intervals (CIs) of the subgroups of RD use for recent or established HIV infection. Results A total of 4496 Chinese MSM participated; 28.4% used RDs, and 5% used multiple types of RDs. The prevalence of each RD use was as follows: poppers (25.9%), ecstasy (2.4%), ketamine (1.2%), amphetamine (0.6%), tramadol (0.4%), methamphetamine (3.8%), and codeine (1.9%). Users of multiple RDs commonly used poppers combined with one or more other types of RDs. Multiple RD users were likely to be aged 26–30 years (vs. 18–25 and > 30 years), live in non-local cities (vs. local cities), never married (vs. married), have a high monthly income (vs. no income and 1–599 USD), use versatile positions during anal intercourse (vs. top or bottom), and have inadequate HIV-related prevention knowledge (vs. adequate). As the number of RDs used in the previous 6 months increased, the prevalence of HIV-related high-risk behaviors increased (P

Dexamethasone has been widely used after various neurosurgical procedures due to its anti-inflammatory property and the abilities to restore vascular permeability, inhibit free radicals, and reduce cerebrospinal fluid production. According to the latest guidelines for the treatment of traumatic brain injury in the United States, high-dose glucocorticoids cause neurological damage. To investigate the reason why high-dose glucocorticoids after traumatic brain injury exhibit harmful effect, rat controlled cortical impact models of traumatic brain injury were established. At 1 hour and 2 days after surgery, rat models were intraperitoneally administered dexamethasone 10 mg/kg. The results revealed that 31 proteins were significantly upregulated and 12 proteins were significantly downregulated in rat models of traumatic brain injury after dexamethasone treatment. The Ingenuity Pathway Analysis results showed that differentially expressed proteins were enriched in the mitochondrial dysfunction pathway and synaptogenesis signaling pathway. Western blot analysis and immunohistochemistry results showed that Ndufv2, Maob and Gria3 expression and positive cell count in the dexamethasone-treated group were significantly greater than those in the model group. These findings suggest that dexamethasone may promote a compensatory increase in complex I subunits (Ndufs2 and Ndufv2), increase the expression of mitochondrial enzyme Maob, and upregulate synaptic-transmission-related protein Gria3. These changes may be caused by nerve injury after traumatic brain injury treatment by dexamethasone. The study was approved by Institutional Ethics Committee of Beijing Neurosurgical Institute (approval No. 201802001) on June 6, 2018.

ObjectiveThe relationship between subclinical atherosclerosis and hearing impairment (HI) has not been widely considered. Brachial ankle pulse wave velocity (baPWV) is a good indicator of muscular artery elasticity and could be a feasible method to screen for subclinical atherosclerosis. Our study aimed to elucidate the relationship between baPWV and HI.MethodsThis cross-sectional study was based on the Kailuan cohort. All participants completed a standardized questionnaire and underwent physical examinations and laboratory assessments at recruitment. Since 2010, some participants received additional baPWV testing during follow-up visits, and some who were exposed to occupational hazards such as noise received a pure-tone average hearing threshold (PTA) test after 2014. Male subjects with a complete physical examination, baPWV, and PTA data were recruited for this study. HI was defined as PTA > 25 dB. Multivariate linear and multivariate logistic regression analyses were used to evaluate the relationship between baPWV and PTA or HI.ResultsAmong 11,141 subjects, the age range was 18–65 years, with mean age of 43.3 ± 8.9 years, the average PTA was 20.54 ± 10.40 dB, and the detection rate of HI was 1,821/11,141 (16.3%). Subjects were divided into four subgroups according to baPWV quartile. As the baPWV quartile increased, age, systolic blood pressure, diastolic blood pressure, body mass index, total cholesterol, high-density-lipoprotein cholesterol, fasting blood glucose, PTA, and proportions of subjects reporting smoking, alcohol consumption, hypertension, and diabetes increased significantly (p < 0.05 for trend). The odds of HI were higher in the fourth quartile group [adjusted odds ratio (aOR): 1.33, 95% CI: 1.10–1.62] than in the first quartile group. For every 100 m/s increase in baPWV, the PTA increased by 13 dB (95% CI: 4–23). When we divided the subjects into young (5,478 subjects; age range 22–44 years; mean age 35.6 ± 5.5 years) or non-young subgroups (5,663 subjects; age range 45–65 years; mean age 50.7 ± 3.7 years) based on a cut-off age of 45 years, the aOR of the fourth quartile group increased to 2.65 (95% CI: 1.68–4.19), and the PTA increment increased to 18 dB (95% CI: 10–27) for every 100 m/s increase in baPWV in the young subgroup. However, this relationship became statistically insignificant in the non-young subgroup.ConclusionOur study revealed the quantitative relationship between baPWV and HI in the Kailuan cohort subjects, although the results are not universally consistent in different populations.

Abstract. Benign paroxysmal positional vertigo (BPPV) is the most common vestibular peripheral disease, and has increasingly become the focus of research on vertigo diseases in recent years. In particular, otolaryngology and neurology societies worldwide have placed a greater focus on the study of BPPV. This article reviews the current diagnosis and treatment status and research progress of benign paroxysmal positional vertigo in China from the aspects of disease etiology, pathology, and pathophysiology. We will also consider potential future research in this field.

Interleukin 17 (IL-17) and its main producer, T cell receptor γδ cells, have neurotoxic effects in the pathogenesis of intracerebral hemorrhage (ICH), aggravating brain injuries. To investigate the correlation between IL-17 and ICH, we dynamically screened serum IL-17 concentrations using enzyme-linked immunosorbent assay and explored the clinical values of IL-17 in ICH patients. There was a significant negative correlation between serum IL-17 level and neurological recovery status in ICH patients (r = –0.498, P < 0.01). To study the neurotoxic role of IL-17, C57BL/6 mice were used to establish an ICH model by injecting autologous blood into the caudate nucleus. Subsequently, the mice were treated with mouse neural stem cells (NSCs) and/or IL-17 neutralizing antibody for 72 hours. Flow cytometry, brain water content detection, Nissl staining, and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling results indicated that NSC transplantation significantly reduced IL-17 expression in peri-hematoma tissue, but there was no difference in T cell receptor γδ cells. Compared with the ICH group, there were fewer apoptotic bodies and more Nissl bodies in the ICH + NSC group and the ICH + NSC + IL-17 group. To investigate the potential effect of IL-17 on directional differentiation of NSCs, we cultured mouse NSCs (NE-4C) alone or co-cultured them with T cell receptor γδ cells, which were isolated from mouse peripheral blood mononuclear cells, for 7 days. The results of western blot assays revealed that IL-17 secreted by T cell receptor γδ cells reduced the differentiation of NSCs into astrocytes and neurons, while IL-17 neutralization relieved the inhibition of directional differentiation into astrocytes rather than neurons. In conclusion, serum IL-17 levels were elevated in the early stage of ICH and were negatively correlated with outcome in ICH patients. Animal experiments and cytological investigations therefore demonstrated that IL-17 probably has neurotoxic roles in ICH because of its inhibitory effects on the directional differentiation of NSCs. The application of IL-17 neutralizing antibody may promote the directional differentiation of NSCs into astrocytes. This study was approved by the Clinical Research Ethics Committee of Anhui Medical University of China (For human study: Approval No. 20170135) in December 2016. All animal handling and experimentation were reviewed and approved by the Institutional Animal Care and Use Committee of Anhui Medical University (approval No. 20180248) in December 2017.

Objective: To explore the utility of ear molding in the treatment of congenital auricular deformations.Study Design: A retrospective chart/photograph review of a consecutive series of infants treated with the EarWell System from 2017 to 2020 was performed. Data on type of auricular deformity, treatment side, and auricular length and width were collected weekly for all study participants.Result: A total of 173 patients (274 ears) with congenital auricular anomalies were included. The treatment duration for lop ears and Stahl's ears was shorter than for other deformations. The mean treatment EarWell duration of participants who started ear molding within 14 days of birth was shorter than that of those who started treatment more than 14 days after birth with the same ear deformation. For participants with unilateral ear deformities, the length and width of both the affected and healthy ears increased over the course of treatment, equalizing after 3 weeks. For participants with bilateral ear deformities, the length and width of both ears increased rapidly over the first 3 weeks of treatment, and the length and width of both ears gradually equalized after treatment.Conclusion: Ear molding is an important intervention for treating congenital auricular deformations, and can increase auricular length and width. Early identification and initiation of treatment is crucial in the management of congenital auricular deformation.

BackgroundHIV self-testing (HIVST) kits are common in key sexually active populations. Direct secondary distribution of HIVST kits (DSDHK) is effective in improving the uptake of HIVST. However, there are concerns about the various limitations of DSDHK, including limited geographic reach, payment problems, and need for face-to-face interactions. ObjectiveIn this study, we aim to evaluate the feasibility and characteristics of indirect secondary distribution of HIVST kits (ISDHK) via WeChat (distributing HIVST application links and follow-up HIVST kits to partners) among men who have sex with men (MSM). MethodsFrom October 2017 to September 2019, an HIVST recruitment advertisement was disseminated on the WeChat social media platform to invite MSM to apply for the HIVST kits (referred to as index participants [IPs]). All MSM participants were encouraged to distribute the HIVST application link to their friends and sexual partners (referred to as alters) through their social networks. All the alters were further encouraged to continue distributing the HIVST application link. All participants paid a deposit (US $7), which was refundable upon completion of the questionnaire, and uploaded the test results via a web-based survey system. ResultsA total of 2263 MSM met the criteria and successfully applied for HIVST. Of these, 1816 participants returned their HIVST results, including 1422 (88.3%) IPs and 394 (21.7%) alters. More alters had condomless anal intercourse, a higher proportion of them had never previously tested for HIV, and they showed a greater willingness to distribute HIVST kits to their sexual partners (P=.002) than the IPs. After controlling for age, education, and income, the alters had a greater proportion of MSM who had never tested for HIV before (adjusted odds ratio [aOR] 1.29, 95% CI 1.00-1.68), were more willing to distribute the HIVST application link (aOR 1.71, 95% CI 1.21-2.40), had a lower number of sexual partners (aOR 0.71, 95% CI 0.57-0.90), and were less likely to search for sexual partners on the web (aOR 0.78, 95% CI 0.60-1.02) than IPs. In comparison, the rates of reactive HIVST results, conducting HIV confirmatory tests, HIV seropositivity, and initiation of HIV antiretroviral therapy were similar for IPs and alters. ConclusionsThe ISDHK model of distributing HIVST application links among the MSM population via social media is feasible. The ISDHK model should be used to supplement the DSDHK model to enable a greater proportion of the MSM population to know their HIV infection status.

Dye degradation is a key reaction in organic decomposition production through electron donor transferring. Palladium (Pd) is the best-known element for synthesis Pd-based catalyst, the surface status determines the scope of relative applications. Here we first prepare Pd-Cu alloy nanoparticles (NPs) by co-reduction of Cu(acac)2 (acac = acetylacetonate) and Pd(C5HF6O2)2 in the presence of sodium borohydride (NaBH4) and glutathione (GSH). The obtained Pd-Cu is about ~10 nm with super-hydrophilicity in aqueous mediums. The structural analysis clearly demonstrated the uniform distribution of Pd and Cu element. The colloidal solution keeps stability even during 30 days. Bimetallic Pd-Cu NPs shows biocompatibility in form of cell lines (IMEF, HACAT, and 239 T) exposed to colloidal solution (50 µg mL−1) for 2 days. It shows the catalytic multi-performance for dye degradation such as methyl orange (MO), rhodamine B (RhB), and methylene blue (MB), respectively. The as-synthesized nanoparticles showed one of the best multiple catalytic activities in the industrially important (electro)-catalytic reduction of 4-nitrophenol (4-NP) to corresponding amines with noticeable reduced reaction time and increased rate constant without the use of any large area support. In addition, it exhibits peroxidase-like activity in the 3, 3′, 5, 5′-Tetramethylbenzidine (TMB) color test and exhibit obvious difference with previous individual metal materials. By treated with high intensity focused ultrasound filed (HIFU), Pd-Cu NPs might be recrystallized and decreased the diameters than before. The enhancement in catalytic performance is observed obviously. This work expedites rational design and synthesis of the high-hierarchy alloy catalyst for biological and environment-friendly agents.

Metal-based enzyme mimics are considered to be acceptable agents in terms of their biomedical and biological properties; among them, iron oxides (Fe3O4) are treated as basement in fabricating heterogeneous composites through variable valency integrations. In this work, we have established a facile approach for constructing Fe3O4@Ag composite through assembling Fe3O4 and Ag together via polyethyleneimine ethylenediamine (PEI) linkages. The obtained Fe3O4@PEI@Ag structure conveys several hundred nanometers (~150 nm). The absorption peak at 652 nm is utilized for confirming the peroxidase-like activity of Fe3O4@PEI@Ag structure by catalyzing 3,3′,5,5′-tetramethylbenzidine (TMB) in the presence of H2O2. The Michaelis–Menten parameters (Km) of 1.192 mM and 0.302 mM show the higher catalytic activity and strong affinity toward H2O2 and TMB, respectively. The maximum velocity (Vmax) value of 1.299 × 10−7 M·s−1 and 1.163 × 10−7 M·s−1 confirm the efficiency of Fe3O4@PEI@Ag structure. The biocompatibility illustrates almost 100% cell viability. Being treated as one simple colorimetric sensor, it shows relative selectivity and sensitivity toward the detection of glucose based on glucose oxidase. By using indocyanine green (ICG) molecule as an additional factor, a remarkable temperature elevation is observed in Fe3O4@PEI@Ag@ICG with increments of 21.6 ∘C, and the absorption peak is nearby 870 nm. This implies that the multifunctional Fe3O4@PEI@Ag structure could be an alternative substrate for formatting acceptable agents in biomedicine and biotechnology with enzymatic and photothermal properties.

In this work, we firstly report the preparation of heterogeneously assembled structures Au-Ag nanoclusters (NCs) as good drug carriers with high loading performance and biocompatible capability. As glutathione-protected Au and Ag clusters self-assembled into porous Au-Ag NCs, the size value is about 1.358 (±0.05) nm. The morphology characterization revealed that the diameter of Au-Ag NCs is approximately 120 nm, as well as the corresponding potential ability in loading performance of the metal cluster triggered-assembling process. Compared with individual components, the stability and loading performance of heterogeneous Au-Ag NCs were improved and exhibit that the relative biocompatibility was enhanced. The exact information about this is that cell viability was approximately to 98% when cells were incubated with 100 µg mL−1 particle solution for 3 days. The drug release of Adriamycin from Au-Ag NCs was carried out in PBS at pH = 7.4 and 5.8, respectively. By simulating in vivo and tumor microenvironment, the release efficiency could reach over 65% at pH = 5.8 but less than 30% at pH = 7.2. Using an ultrasound field as external environment can accelerate the assembling process while metal clusters triggered assembling Au-Ag NCs. The size and morphology of the assembled Au-Ag NCs can be controlled by using different power parameters (8 W, 13 W, 18 W) under ambient atmosphere. Overall, a novel approach is exhibited, which conveys assembling work for metal clusters triggers into heterogeneous structures with porous characteristic. Its existing properties such as water-solubility, stability, low toxicity and capsulation can be considered as dependable agents in various biomedical applications and drug carriers in immunotherapies.

This paper analyzes the stability problem of continuous-time switched systems with all subsystems unstable. With each switched system having a minimum dwell time, this paper considered that the Lyapunov function converges in the minimum dwell time and diverges beyond the minimum dwell time, respectively. Based on that, a new globally uniformly exponentially stability (GUES) result under average dwell time (ADT) method is proposed. By using a time-dependent quadratic Lyapunov function method, convex sufficient conditions for switched linear systems are derived. The resulting conditions in this paper are enforced using the sum of squares (SOS) programming. In real-world, equipment noise is unavoidable, which may result in inaccurate system matrices measurements. Therefore, it is necessary to analyze the stability of uncertain systems. Therefore, the condition for switched linear systems is extended to uncertain systems and the robust stability condition is derived. Some numerical examples are given to illustrate the advantages of our established results.

In this paper, the stability problem of discrete-time switched nonlinear systems with all subsystems unstable is investigated. The nonlinear subsystems are represented by the Takagi-Sugeno (T-S) fuzzy models. By constructing a novel piecewise multiple Lyapunov function approach, an exponential stability condition of switched T-S fuzzy systems is first established with the bounded maximum average dwell time. A numerical example is finally provided to illustrate the effectiveness of the obtained theoretical results.

The prognosis of glioma is significantly correlated with the pathological grades; however, the correlations between the prognostic biomarkers with pathological grades have not been elucidated. S100A11 is involved in a variety of malignant biological processes of tumor, whereas its biological and clinicopathological features on glioma remain unclear. In this study, the S100A11 expression and clinical information were obtained from the public databases (TCGA, GEPIA2) to analyze its correlations with the pathological grade and the prognosis of glioma patients. We then verified the expression of S100A11 by immunohistochemistry staining. The effects of S100A11 on the proliferation of glioma cells were confirmed by cytological function assays (CCK-8, Flow cytometry, Clone formation assay) in vitro , the role of S100A11 in regulation of glioma growth was determined by xenograft model assay. We observed that S100A11 expression positively correlated with the pathological grades, while negatively correlated with the survival time of patients. In cytological analysis, we found the proliferations of glioma cell lines were significantly inhibited in vitro ( P < 0.05) after interfering S100A11 expression via shRNAs. The cell cycle was blocked at G0/G1 stage. The ability of clone formation was significantly decreased, and the tumorigenicity in vivo was weakened ( P < 0.05). In summary, S100A11 was over-expressed in gliomas and positively correlated with the pathological grades. Interfering the expression of S100A11 significantly inhibited the proliferation of glioma in vitro and the tumorigenicity in vivo ( P < 0.05). In conclusion, S100A11 might be considered as a potential biomarker in glioma.

The loss of auditory sensory hair cells (HCs) is the most common cause of sensorineural hearing loss (SNHL). As the main sound transmission structure in the cochlea, it is necessary to maintain the normal shape and survival of HCs. In this review, we described and summarized the signaling pathways that regulate the development and survival of auditory HCs in SNHL. The role of the mitogen-activated protein kinase (MAPK), phosphoinositide-3 kinase/protein kinase B (PI3K/Akt), Notch/Wnt/Atoh1, calcium channels, and oxidative stress/reactive oxygen species (ROS) signaling pathways are the most relevant. The molecular interactions of these signaling pathways play an important role in the survival of HCs, which may provide a theoretical basis and possible therapeutic interventions for the treatment of hearing loss.

High-temperature Daqu, also called Jiang-flavor Daqu, is the saccharifying and fermenting agent for brewing Jiang-flavor Baijiu. During the spontaneous solid-state fermentation of high-temperature Daqu, variations in temperature and moisture lead to microbial diversity and various metabolites, contributing to the different colors of high-temperature Daqu (customarily referred to as white Daqu, black Daqu, yellow Daqu, and red Daqu in production). We aimed to investigate the differences in microbial communities, physicochemical indices, and potential functions among different high-temperature Daqu with different colors (labeled as QW, QB, QY, and QR) by amplicon sequencing. We found that Kroppenstedtia, Bacillus, and Thermoascus were predominant in all samples; Saccharopolyspora and Thermomyces were predominant in QB and QR; and Unclassfied_O_Eurotiales were predominant in QY. The results on the physicochemical characteristics indicated that compared with other Daqu samples, QW exhibited higher protease activity and lower acidity, whereas QB showed the opposite results. QR had the highest esterification yield, and QY exhibited the highest saccharification but lowest esterification yield. Functional prediction demonstrated that the higher abundances of genes encoding bacterial enzymes of QW and QY were related to the considerably higher abundances of Kroppenstedtia in QW (59%) and QY (87%), respectively. The highest abundance of Thermomyces in QB (80%) contributed to the highest abundance of genes encoding fungal enzymes in QB. This study revealed the microbial and functional dissimilarities of color-based high-temperature starters and helped facilitate the liquor fermentation process.

In the auditory system, ribbon synapses are vesicle-associated structures located between inner hair cells (IHCs) and spiral ganglion neurons that are implicated in the modulation of trafficking and fusion of synaptic vesicles at the presynaptic terminals. Synapse loss may result in hearing loss and difficulties with understanding speech in a noisy environment. This phenomenon happens without permanent hearing loss; that is, the cochlear synaptopathy is “hidden.” Recent studies have reported that synapse loss might be critical in the pathogenesis of hidden hearing loss. A better understanding of the molecular mechanisms of the formation, structure, regeneration, and protection of ribbon synapses will assist in the design of potential therapeutic strategies. In this review, we describe and summarize the following aspects of ribbon synapses: (1) functional and structural features, (2) potential mechanisms of damage, (3) therapeutic research on protecting the synapses, and (4) the role of synaptic regeneration in auditory neuropathy and the current options for synapse rehabilitation.

Powder solid sampling atomic emission spectrometry is a simple sample pretreatment method with high sensitivity, low detection limit, and little environmental pollution. This method has been applied to the simultaneous analysis of trace Ag, B and Sn in geochemical samples. However, the serious matrix effect limits the application of this method. Based on the Scanning Electron Microscopy (SEM) technique, the differences in the composition of the reaction products at different times for specific formulations and different samples was compared. Combined with the evaporation curve to reverse the reaction process, a carrier buffer suitable for different types of geochemical samples was developed. In order to realize the improvement of the arc burning process, K2S2O7 and NaF were used as flux during preparing carrier buffer to catalytically decompose the matrix. Synergizing with PTFE and sedimentation S promotes rapid evaporation of analyzed elements in various forms. The formation of Al2O3-SiO2-CaO-BaO mutual melt lowers the Tammann temperature and can absorb matrix oxides in-situ, suppressing the interferences. Compared with the available method, the sensitivity increased by 1.2 times, and the precision, accuracy and detection limit are superior to a number of geochemical survey specifications.

Abstract Intimate partner violence (IPV) and HIV are highly prevalent worldwide among MSM. However, the association between IPV and HIV seroconversion is virtually unknown. This 12-month prospective cohort study was conducted among MSM in Shenyang, China to explore the causality between IPV and the incidence of HIV. Adjusted Hazard Ratios (aHRs) of HIV acquisition were derived from a multivariate time-dependent Cox model and applied to calculate population attributable fractions (PAFs). Among 476 HIV-negative MSM subjects, 89(18.7%) reported being victims of IPV in the past 3 months (P3M). IPV was significantly correlated with lower education, having more condomless anal intercourse (CAI) and being depressed (each P

Metal-based magnetic materials have been used in different fields due to their particular physical or chemical properties. The original magnetic properties can be influenced by the composition of constituent metals. As utilized in different application fields, such as imaging monitoring, thermal treatment, and combined integration in cancer therapies, fabricated metal-based magnetic materials can be doped with target metal elements in research. Furthermore, there is one possible new trend in human activities and basic cancer treatment. As has appeared in characterizations such as magnetic resonance, catalytic performance, thermal efficiency, etc., structural information about the real morphology, size distribution, and composition play important roles in its further applications. In cancer studies, metal-based magnetic materials are considered one appropriate material because of their ability to penetrate biological tissues, interact with cellular components, and induce noxious effects. The disruptions of cytoskeletons, membranes, and the generation of reactive oxygen species (ROS) further influence the efficiency of metal-based magnetic materials in related applications. While combining with cancer cells, these magnetic materials are not only applied in imaging monitoring focus areas but also could give the exact area information in the cure process while integrating ultrasound treatment. Here, we provide an overview of metal-based magnetic materials of various types and then their real applications in the magnetic resonance imaging (MRI) field and cancer cell treatments. We will demonstrate advancements in using ultrasound fields co-worked with MRI or ROS approaches. Besides iron oxides, there is a super-family of heterogeneous magnetic materials used as magnetic agents, imaging materials, catalytic candidates in cell signaling and tissue imaging, and the expression of cancer cells and their high sensitivity to chemical, thermal, and mechanical stimuli. On the other hand, the interactions between magnetic candidates and cancer tissues may be used in drug delivery systems. The materials’ surface structure characteristics are introduced as drug loading substrates as much as possible. We emphasize that further research is required to fully characterize the mechanisms of underlying ultrasounds induced together, and their appropriate relevance for materials toxicology and biomedical applications.

Essential thrombocythemia (ET) can cause arterial embolism. Patients with arterial thrombosis usually have additional risk factors, such as smoking and hypertension. We report a 70-year-old woman with ET who had no risk factors, except for age. Cranial magnetic resonance imaging showed fresh lacunar infarction in several lobes. Electrocardiography showed ST-segment elevation in leads II, III, and aVF. Coronary angioplasty and stenting were successfully performed. We checked the bone marrow and performed genetic testing. The Janus kinase 2 (JAK2) V617F gene mutation was found. This case was a rare initial presentation of previously undiagnosed ET with embolism of cardiovascular and cerebral vessels. Anti-platelet drugs and hydroxyurea were used to prevent further thrombosis in the coronary and cerebral arteries.

KT/HAK/KUP (KUP) family is responsible for potassium ion (K+) transport, which plays a vital role in the response of plants to abiotic stress by maintaining osmotic balance. However, our understanding of the functions of the KUP family in the drought-resistant crop cassava (Manihot esculenta Crantz) is limited. In the present study, 21 cassava KUP genes (MeKUPs) were identified and classified into four clusters based on phylogenetic relationships, conserved motifs, and gene structure analyses. Transcriptome analysis revealed the expression diversity of cassava KUPs in various tissues of three genotypes. Comparative transcriptome analysis showed that the activation of MeKUP genes by drought was more in roots than that in leaves of Arg7 and W14 genotypes, whereas less in roots than that in leaves of SC124 variety. These findings indicate that different cassava genotypes utilize various drought resistance mechanism mediated by KUP genes. Specific KUP genes showed broad upregulation after exposure to salt, osmotic, cold, H2O2, and abscisic acid (ABA) treatments. Taken together, this study provides insights into the KUP-mediated drought response of cassava at transcription levels and identifies candidate genes that may be utilized in improving crop tolerance to abiotic stress.

The concept of Geosynchronous Circular SAR (Geo-CSAR) is introduced in this paper. With the design of the geosynchronous orbit parameters, a near-circular satellite sub-track could be formed to enable the staring imaging mode, which supports the advanced applications for wide-field and 3-D information acquisition under long-term consistent observation. This paper also analyzes Geo-CSAR's imaging formation capabilities, and concludes its attractive advantages over low-earth orbit spaceborne SAR in terms of instantaneous coverage, consistent observing area, 3-D positioning accuracy and etc.. Encouraging expectations for Geo-CSAR thus could be positively predicted in military investigation and disaster monitoring management applications.

The Normalized Least-Mean-Squares (NLMS) algorithm is widely used to cancel the direct and multiple path interferences in Passive Coherent Location (PCL) radar systems. This study proposes that the interference cancelation using the NLMS algorithm and the calculation of the radar Cross Ambiguity Function (CAF) can be modeled as a notch filter, with the notch located at zero Doppler frequency in the surface of the radar CAF. The analysis shows that the notch’s width and depth are closely related to the step size of the NLMS algorithm. Subsequently, the effect of the notch in PCL radar target detection is analyzed. The results suggest that the detection performance of the PCL radar deteriorates because of the wide notch. Furthermore, the Nonuniform NLMS (NNLMS) algorithm is proposed for removing the clutter with the Doppler frequency by using notch filtering. A step-size matrix is adopted to mitigate the low Doppler frequency clutter and lower the floor of the radar CAF. With the step-size matrix, can be obtained notches of different depths and widths in different range units of the CAF, which can filter the low Doppler frequency clutter. In addition, the convergence rate of the NNLMS algorithm is better than that of the traditional NLMS algorithm. The validity of the NNLMS algorithm is verified by experimental results.

This study presents the development and evaluation of a novel partially open-loop heat pump dryer with a unit-room (HPDU). The unit-room was designed to enable the ambient air to be mixed with the return air, thereby reducing the influence of the ambient air on the system performance, while maintaining a high system thermal efficiency. A modelling system for the HPDU was developed and validated based on a real-scale experimental study. By using the modelling system, the system characteristics under different ambient conditions and bypass factors were analyzed. The energy benefit of the proposed HPDU was quantified through a comparative study with a closed-loop heat pump dryer (CHPD). It is evident that a maximal specific moisture extraction rate (SMER) and a minimal total energy consumption (TEC) existed when changing the bypass factor of the HPDU under certain ambient temperatures. Compared to the CHPD, the coefficient of performance (COP) of the HPDU increased by up to 39.56%, presenting a significant energy benefit for the application of HPDU.

Streptococcus suis has emerged as an important zoonotic pathogen that causes meningitis, arthritis, septicemia and even sudden death in pigs and humans. Quorum sensing is the signaling network for cell-to-cell communication that bacterial cells can use to monitor their own population density through production and exchange of signal molecules. S-Ribosylhomocysteinase (LuxS) is the key enzyme involved in the activated methyl cycle. Autoinducer 2 (AI-2) is the adduct of borate and a ribose derivative and is produced from S-adenosylhomocysteine (SAH). AI-2 can mediate interspecies communication and in some species facilitate the bacterial behavior regulation such as biofilm formation and virulence in both Gram-positive and Gram-negative bacteria. Here, we reported the overexpression, purification and crystallographic structure of LuxS from S. suis. Our results showed the catalytically active LuxS exists as a homodimer in solution. Inductively coupled plasma-mass spectrometry (ICP-MS) revealed the presence of Zn2+ in LuxS. Although the core structure shares the similar topology with LuxS proteins from other bacterial species, structural analyses and comparative amino acid sequence alignments identified two key amino acid differences in S. suis LuxS, Phe80 and His87, which are located near the substrate binding site. The results of site-directed mutagenesis and enzymology studies confirmed that these two residues affect the catalytic activity of the enzyme. These in vitro results were corroborated in vivo by expression of the LuxS variants in a S. suis ΔluxS strain. The single and two amino acid of LuxS variant decreased AI-2 production and biofilm formation significantly compared to that of the parent strain. Our findings highlight the importance of key LuxS residues that influence the AI-2 production and biofilm formation in S.suis.