Development of an immune-related diagnostic predictive model for oral lichen planus

Oral lichen planus (OLP) was a chronic inflammatory disease of unknown etiology with a 1.4% chance of progressing to malignancy. However, it has been suggested in several studies that immune system disorders played a dominant role in the onset and progression of OLP. Therefore, this experiment aimed to develop a diagnostic prediction model for OLP based on immunopathogenesis to achieve early diagnosis and treatment and prevent cancer. In this study, 2 publicly available OLP datasets from the gene expression omnibus database were filtered. In the experimental group (GSE52130), the level of immune cell infiltration was assessed using MCPcounter and ssGSEA algorithms. Subsequently, differential expression analysis and gene set enrichment analysis were performed between the OLP and control groups. The resulting differentially expressed genes were intersected with immunologically relevant genes provided on the immunology database and analysis portal database (ImmPort) website to obtain differentially expressed immunologically relevant genes (DEIRGs). Furthermore, the gene ontology and kyoto encyclopedia of genes and genomes analyses were carried out. Finally, protein-protein interaction network and least absolute shrinkage and selection operator regression analyses constructed a model for OLP. Receiver operating characteristic curves for the experimental and validation datasets (GSE38616) were plotted separately to validate the model's credibility. In addition, real-time quantitative PCR experiment was performed to verify the expression level of the diagnostic genes. Immune cell infiltration analysis revealed a more significant degree of inflammatory infiltration in the OLP group compared to the control group. In addition, the gene set enrichment analysis results were mainly associated with keratinization, antibacterial and immune responses, etc. A total of 774 differentially expressed genes was obtained according to the screening criteria, of which 65 were differentially expressed immunologically relevant genes. Ultimately, an immune-related diagnostic prediction model for OLP, which was composed of 5 hub genes (BST2, RNASEL, PI3, DEFB4A, CX3CL1), was identified. The verification results showed that the model has good diagnostic ability. There was a significant correlation between the 5 hub diagnostic biomarkers and immune infiltrating cells. The development of this model gave a novel insight into the early diagnosis of OLP.

Auxochrome Dimethyl-Dihydroacridine Improves Fluorophores for Prolonged Live-Cell Super-Resolution Imaging

Superior photostability, minimal phototoxicity, red-shifted absorption/emission wavelengths, high brightness, and an enlarged Stokes shift are essential characteristics of top-tier organic fluorophores, particularly for long-lasting super-resolution imaging in live cells (e.g., via stimulated emission depletion (STED) nanoscopy). However, few existing fluorophores possess all of these properties. In this study, we demonstrate a general approach for simultaneously enhancing these parameters through the introduction of 9,9-dimethyl-9,10-dihydroacridine (DMA) as an electron-donating auxochrome. DMA not only induces red shifts in emission wavelengths but also suppresses photooxidative reactions and prevents the formation of triplet states in DMA-based fluorophores, greatly improving photostability and remarkably minimizing phototoxicity. Moreover, the DMA group enhances the fluorophores' brightness and enlarges the Stokes shift. Importantly, the "universal" benefits of attaching the DMA auxochrome have been exemplified in various fluorophores including rhodamines, difluoride-boron complexes, and coumarin derivatives. The resulting fluorophores successfully enabled the STED imaging of organelles and HaloTag-labeled membrane proteins.

The SlGRAS9-SlZHD17 transcriptional cascade regulates chlorophyll and carbohydrate metabolism contributing to fruit quality traits in tomato

Some essential components of fleshy fruits are dependent on photosynthetic activity and carbohydrate metabolism. Nevertheless, the regulatory mechanisms linking chlorophyll and carbohydrate metabolism remain partially understood. Here, we uncovered the role of SlGRAS9 and SlZHD17 transcription factors in controlling chlorophyll and carbohydrate accumulation in tomato fruit. Knockout or knockdown of SlGRAS9 or SlZHD17 resulted in marked increase in chlorophyll content, reprogrammed chloroplast biogenesis and enhanced accumulation of starch and soluble sugars. Combined genome-wide transcriptomic profiling and promoter-binding experiments unveiled a complex mechanism in which the SlGRAS9/SlZHD17 regulatory module modulates the expression of chloroplast and sugar metabolism either via a sequential transcriptional cascade or through binding of both TFs to the same gene promoters, or, alternatively, via parallel pathways where each of the TFs act on different target genes. For instance, the regulation of SlAGPaseS1 and SlSUS1 is mediated by SlZHD17 whereas that of SlVI and SlGLK1 occurs only through SlGRAS9 without the intervention of SlZHD17. Both SlGRAS9 and SlZHD17 can also directly bind the promoter of SlPOR-B to regulate its expression. Taken together, our findings uncover two important regulators acting synergistically to manipulate chlorophyll and carbohydrate accumulation and provide new potential breeding targets for improving fruit quality in fleshy fruits.

A novel chemokine biomarker to distinguish active tuberculosis from latent tuberculosis: a cohort study

BACKGROUND

Interferon-γ release assays (IGRAs), which are widely used to diagnose tuberculosis (TB), cannot effectively discriminate latent TB infection (LTBI) from active TB (ATB). This study aimed to identify potential antigen-specific biomarkers for differentiating LTBI cases from ATB cases.

METHODS

Ongoing recruitment was conducted of individuals meeting study inclusion criteria at Beijing Chest Hospital from May 2020 to April 2022; 208 participants were enrolled and assigned to three groups: HC (60 healthy controls), LTBI (52 subjects with LTBI) and ATB (96 ATB patients). After participants were assigned to the discovery cohort (20 or 21 subjects/group), all others were assigned to the verification cohort. Discovery cohort blood levels of 40 chemokines were measured using Luminex assays to identify chemokines that could be used to discriminate LTBI cases from ATB cases; candidate biomarkers were verified using enzyme-linked immunosorbent assay-based testing of validation cohort samples.

RESULTS

Luminex results revealed highest ATB group levels of numerous cytokines, growth factors and chemokines. Receiving operating characteristic curve-based analysis of 40 biomarkers revealed CCL8 (AUC = 0.890) and CXCL9 (AUC = 0.883) effectively discriminated between LTBI and TB cases; greatest diagnostic efficiency was obtained using both markers together (AUC = 0.929). Interpretation of CCL8 and CXCL9 levels for validation cohort IGRA-positive subjects (based on a 0.658-ng/ml cutoff) revealed ATB group CCL8-based sensitivity and specificity rates approaching 90.79% and 100.00%, respectively.

CONCLUSION

TB-specific chemokines hold promise as ATB diagnostic biomarkers. Additional laboratory confirmation is needed to establish whether CCL8-based assays can differentiate between ATB and LTBI cases, especially for bacteriologically unconfirmed TB cases.

The Lnc-RNA APPAT Suppresses Human Aortic Smooth Muscle Cell Proliferation and Migration by Interacting With MiR-647 and FGF5 in Atherosclerosis

PURPOSE

LncRNA-Atherosclerotic plaque pathogenesis-associated transcript (APPAT) could be detected in circulating blood and has been demonstrated to correlate with the development of atherosclerosis in our previous work. It could be a potential noninvasive biomarker for earlier diagnoses of clinical cardiovascular disease. Moreover, the expression of miR-647 increased in ox-LDL-treated vascular smooth muscle cells and peripheral blood of patients with coronary heart disease. A negative correlation between APPAT and miR-647 was confirmed, and FGF5 was screened as molecular target of miR-647. However, it is largely unclear how APPAT, miR-647, and FGF5 interact and function in disease development. Here, we aim to explore the underlying molecular mechanism in this progression.

MATERIALS AND METHODS

APPAT, miR-647, and FGF5 expression levels were detected by quantitative reverse transcription polymerase chain reaction; cell proliferation was detected by EdU incorporation assay; cell migration was detected by wound-healing assay; the molecular interaction of APPAT/FGF5 with miR-647 was verified by dual-luciferase reporter assay; the western blot was performed to determine the gene expression at protein levels; subcellular localizations of APPAT and miR-647 were observed by fluorescence in situ hybridization; cytosolic and nucleus fractionation assay was performed to further detect the distribution of miR-647.

RESULTS

APPAT and miR-647 have inverse effects on human aortic smooth muscle cells' (HASMCs) proliferation and migration. APPAT negatively regulated the cell activity, whereas miR-647 did it in a positive way (p<0.05). Three pairs of molecular interplay were found: mutual negative regulation between APPAT and miR-647, APPAT downregulated FGF5, miR-647 regulation on FGF5 (p<0.05). Subcellular location assay confirmed the molecular interaction of APPAT and miR-647.

CONCLUSIONS

APPAT could suppress the migration and proliferation of ox-LDL-treated HASMCs via interacting with miR-647 and FGF5. We revealed a nontypical competing endogenous RNA mechanism of long noncoding RNA in the progression of atherosclerosis.

Identification of SRS transcription factor family in Solanum lycopersicum, and functional characterization of their responses to hormones and abiotic stresses

The SHI RELATED SEQUENCE (SRS) family plays a vital role in the development of multiple plant organs such as floral meristem determinacy, organ morphogenesis, and signal transduction. Nevertheless, there is little understanding of the biological significance of tomato SRS family at this point. Our research identified eight SlSRS family members and classified them into three subfamilies based on phylogenetics, conserved motifs, and characteristic domain analysis. The intraspecies and interspecies collinearity analysis revealed clues of SRS family evolution. Many cis-elements related to hormones, stresses, and plant development can be found in the promoter region of SlSRS genes. All of eight SlSRS proteins were located in the nucleus and possessed transcriptional activity, half of which were transcriptional activators, and the other half were transcriptional repressors. Except for SlSRS1, which showed high transcript accumulation in vegetative organs, most SlSRS genes expressed ubiquitously in all flower organs. In addition, all SlSRS genes could significantly respond to at least four different plant hormones. Further, expression of SlSRS genes were regulated by various abiotic stress conditions. In summary, we systematically analyzed and characterized the SlSRS family, reviewed the expression patterns and preliminarily investigated the protein function, and provided essential information for further functional research of the tomato SRS genes in the determination of reproductive floral organs and the development of plants, and possibly other plants.

Conductive Viologen Hydrogel Based on Hyperbranched Polyamidoamine for Multiple Stimulus-Responsive Drug Delivery

The emergence of precision medicine and personalized pharmacotherapy has led to the development of advanced drug delivery systems that can respond to multiple stimuli. Conductive hydrogels have excellent electrical signal responsiveness and drug storage capabilities; however, current conductive hydrogels suffer from poor mechanical properties, low ionic conductivity, and high voltage. Herein, a covalently crosslinked viologen hydrogel was prepared using electroactive hyperbranched polyamidoamine (EHP) as the crosslinking center in a polymeric network. Attributed to its unique molecular architecture, this hydrogel exhibits improved mechanical properties (high tensile strength and desirable stretchability up to 1280%). Approvable ionic conductivity, biocompatibility, antibacterial properties, and wearable strain-sensing performance were also disclosed, ascribed to the participation of versatile viologen groups in the hydrogel structure. This hydrogel exhibited high efficiency in drug release (81.6%) at a lower voltage of -1.2 V. Moreover, fascinating pH-stimulus drug release behavior was also demonstrated in both acidic and alkalescent environments owing to the dramatic conformational transition of EHP. This work provides a new design strategy for conductive hydrogels for multiple stimulus-responsive drug delivery systems.

A rare case of cardiogenic shock caused by takotsubo syndrome associated with SARS-CoV-2 infection: The value of echocardiography in the diagnosis and monitoring of the efficacy of extracorporeal membrane oxygenation

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mainly invades the respiratory system, but may also cause various cardiovascular complications. We report a rare case of myocarditis associated with SARS-CoV-2 infection. A 61-year-old man was admitted to the hospital with a positive nucleic acid test for SARS-CoV-2. A sudden increase in troponin level (up to .144 ng/mL) was observed on the 8th day after admission. He developed symptoms of heart failure and progressed rapidly to cardiogenic shock. Echocardiography on the same day showed reduced left ventricular ejection fraction, reduced cardiac output, and segmental ventricular wall motion abnormalities. Takotsubo cardiomyopathy associated with SARS-CoV-2 infection was considered based on the typical echocardiography findings. We immediately started veno-arterial extracorporeal membrane oxygenation (VA-ECMO) treatment. The patient was successfully withdrawn from VA-ECMO after 8 days following recovery of ejection fraction to 65% and all indicators qualifying the withdrawal criteria. Echocardiography plays an important role in dynamic monitoring of cardiac changes in such cases and can help determine the timing of extracorporeal membrane oxygenation treatment and withdrawal.

First report on the molecular detection of Enterocytozoon bieneusi in livestock and wildlife around Qinghai Lake in the Qinghai-Tibetan Plateau area, China

Enterocytozoon bieneusi is considered to be a microsporidial species of humans and animals in the worldwide. Limited data have been reported on the prevalence and genotypes of E. bieneusi in livestock and wild animals around Qinghai Lake in the Qinghai-Tibetan Plateau area, which shares water sources, grasslands, and harsh climate with high altitudes. In this study, fecal samples from 110 Tibetan sheep, 128 yaks, 227 wild birds, 96 blue sheep (Pseudois nayaur) and 268 Przewalski's gazelle (Procapra przewalskii) around Qinghai Lake were collected, and then tested for E. bieneusi by PCR and sequencing analysis based on the ribosomal internal transcribed spacer. Among them, ten (9.09%) samples from Tibetan sheep, five (3.91%) from yaks, five (2.20%) from wild birds, one (1.04%) from wild blue sheep and two (0.75%) from Przewalski's gazelle were positive for E. bieneusi. Among sheep, there were nine E. bieneusi genotypes, including two known genotypes (BEB6 and J), and seven novel genotypes (named CHS18-CHS24). From yaks, four genotypes were identified, including two known ones (BEB4 and J) and two novel genotypes (named CHN15 and CHN16). While in wild animals, eight genotypes were found, including five different genotypes from wild bids, with three known genotypes (EbpC, J and NCF2), two novel genotypes (named CHWB1 and CHS24), and two genotypes from Przewalski's gazelle, with one known genotype J and one novel genotype CHWPG1, and one novel genotype CHWBS1 from blue sheep. According to the phylogenetic analysis, five isolates belonged to group 1, and the others were clustered into group 2. This study provides unique data on the epidemiological reports and potential risk factors for E. bieneusi in both domesticated livestock and wild animals around Qinghai Lake in the Qinghai-Tibetan Plateau area; it is important to better understand the molecular epidemiology and zoonotic potential of E. bieneusi in the Qinghai-Tibetan Plateau area.

A40 GUT MICROBIOTA PROMOTES NUTRIENT AVAILABLITY AND PATHOGENESIS OF AN ATTACHING/ EFFACING BACTERIAL PATHOGEN

Background

Our gut microbiota plays an important role in protecting the gastrointestinal (GI) tract from invading enteric pathogens. Much of this colonization resistance is mediated by limiting nutrient availability, however, enteric pathogens have evolved strategies to subvert this competition, utilizing commensal metabolites to facilitate their infection. Access to nutrients is not only crucial for a pathogen’s metabolic fitness, but can also drive the expression of virulence factors, a process high in energy demands. In addition, enteric pathogens, such as the attaching and effacing (A/E) bacterium Citrobacter rodentium, must cross the colonic mucus layer that normally prevents their direct access to the underlying epithelium. Intestinal mucus is comprised of highly glycosylated mucins, with the sugar sialic acid frequently occupying the terminal position of their O-glycan side chains. We hypothesize that C. rodentium utilizes commensal-liberated mucin sugars, such as sialic acid, as nutrients and signals to promote its virulence.

Purpose

This study investigates the mechanisms by which A/E pathogens reach the colonic mucosal surface, and the role played by commensal microbes in facilitating the infection.

Method

Expression of virulence factors secreted by C. rodentium in the presence or absence of sialic acid was analyzed by SDS-PAGE and mass spectrometry. Next, we infected specific-pathogen free (SPF), germfree (GF), and previously GF C57Bl/6 mice mono-colonized with Bacteroides thetaotaomicron, a mucus-degrading commensal, to examine their susceptibility to C. rodentium and to measure the levels of free sialic acid in their feces.

Result(s)

Sensing of sialic acid by C. rodentium, was found to induce the secretion of several key virulence proteins, enhancing the pathogen’s migration across the colonic mucus layer and adhesion to the underlying epithelium. Access to sialic acid within the gut environment was enhanced in the presence of microbiota, as the levels of free sialic acid were low in GF mice. Interestingly, despite GF mice carrying very high C. rodentium burdens, passage across the mucus layer and infection of their colonic epithelium was impaired as compared to SPF mice. Notably, B. thetaotaomicron was found to degrade whole mucus in vitro, facilitating its consumption by C. rodentium for growth, while B. thetaotaomicron mono-colonized GF mice showed increased susceptibility to colonic infection by C. rodentium.

Conclusion(s)

We demonstrate that although commensal microbes promote colonization resistance, as an A/E pathogen infection establishes, specific commensal bacteria accelerate infection in the GI tract by releasing an important nutrient, ie. sialic acid, from mucus. Access to sialic acid promotes C. rodentium virulence by inducing the key virulence factors that facilitate its translocation across the mucus layer as well as adhesion to the epithelium, thereby expediting disease progression.

Please acknowledge all funding agencies by checking the applicable boxes below

CCC, CIHR, Other

Please indicate your source of funding;

CH.I.L.D. Foundation

Disclosure of Interest

None Declared

Efficient and stable Fe3O4@SiO2 core-shell nanospheres for electrochemical water oxidation under neutral condition

To further improve the water oxidation activity of Fe3O4, SiO2-treated Fe3O4 is successfully obtained by a modified Stöber sol–gel process. The resulting Fe3O4@SiO2 nanosphere not only shows noticeable water oxidation...

A New Approach to Optimize SVM for Insulator State Identification Based on Improved PSO Algorithm

The failure of insulators may seriously threaten the safe operation of the power system, where the state detection of high-voltage insulators is a must for the normal and safe operation of the power system. Based on the data of insulators in aerial images, this work explored an enhanced particle swarm algorithm to optimize the parameters of the support vector machine. A support vector machine model was therefore established for the identification of the normal and defective states of the insulators. This methodology works with the structure minimization principle of SVM and the characteristics of particle swarm fast optimization. First, the aerial insulator image was segmented as a target by way of the seed region growth based on double-layer cascade morphological improvements, and then, HOG features plus GLCM features were extracted as sample data. Finally, an ameliorated PSO-SVM classifier was designed to realize insulator state identification. Comparisons were made between PSO-SVM and conventional machine learning algorithms, SVM and Random Forest, and an optimization algorithm, Gray Wolf Optimization Support Vector Machine (GWO-SVM), and advanced neural network CNN. The experimental results showed that the performance of the algorithm proposed in this paper touched the top level, where the recognition accuracy rate was 92.11%, the precision rate 90%, the recall rate 94.74%, and the F1-score 92.31%.

Antioxidant therapy for patients with oral lichen planus: A systematic review and meta-analysis

Aims: This study aimed to systematically review the efficacy and safety of antioxidants for patients with Oral lichen planus (OLP). Methods: Databases, including PubMed, Web of Science, Cochrane Library, Embase, and Google Scholar, were searched up to 30 April 2022, for randomized controlled trials on the antioxidant therapy of OLP. The following endpoints were analyzed: pain score, clinical score, pain resolution rate, clinical resolution rate, and adverse effects. Results: A total of 19 studies met the inclusion criteria, and 17 studies with 704 patients were included in the meta-analysis. The findings showed that antioxidant therapy could significantly reduce the pain score [standardized mean difference -0.72 (-1.36, -0.07), P = 0.03, I2 = 87%, PI2 < 0.00001] and clinical score [SMD -2.06 (-3.06, -1.06), P < 0.0001, I2 = 94%, PI2 < 0.00001] of patients with OLP and improve the pain resolution rate [risk ratio (RR) 1.15 (1.01, 1.31), P = 0.04, I2 = 45%, PI2 = 0.09] and clinical resolution rate [RR 1.40 (1.10, 1.78), P = 0.006, I2 = 72%, PI2 = 0.002]. Conclusion: The study demonstrated that antioxidant therapy was beneficial for patients with OLP, and antioxidants might be used to treat OLP. Systematic Review Registration: https://clinicaltrials.gov/, identifier CRD4202233715.

Demodulation of Fabry-Perot sensors using random speckles

Random speckles are proposed to demodulate Fabry-Perot (FP) sensors in this study. A piece of multimode fiber is used to interrogate the FP transmission spectrum, and tiny spectral changes lead to significant variations in the generated speckle patterns. In the demonstration experiments, the pressure resolution of 0.001 MPa can be obtained from an open cavity FP sensor based on the convolutional neural network (CNN) demodulation algorithm. It is worth noting that the spectral differences in neighboring orders can be precisely distinguished due to the high sensitivity of speckles. Thus, the fringe-order ambiguity problem is solved and the dynamic measurement range can be greatly improved. The speckle-based demodulation scheme provides a new way to balance resolution, dynamic range, speed, and cost of FP sensors.

Genomic and Therapeutic Analyses of Staphylococcus aureus Isolated from Cattle Reproductive Tract

Staphylococcus aureus is emerging as a ubiquitous multidrug-resistant pathogen circulating among animals, humans, and their environment. The current study focused on molecular epidemiology and evidence-based treatment against S. aureus from bovine endometritis. For this study, n = 304 cattle were screened for endometritis using ultrasonography while presenting case history, and clinical signs were also considered. S. aureus was isolated from endometritis-positive uterine samples which were further put to molecular identification, phylogenetic analysis, susceptibility to antibiotics, and testing of novel drug combinations in both in vitro and field trials. The findings of the study revealed 78.20% of bovine endometritis samples positive for S. aureus, while nuc gene-based genotyping of S. aureus thermal nuclease (SA-1, SA-2, and SA-3) showed close relatedness with S. aureus thermal nuclease of Bos taurus. Drug combinations showed 5.00 to 188.88% rise in zones of inhibitions (ZOI) for drugs used in combination compared to the drugs used alone. Gentamicin in combination with amoxicillin and enrofloxacin with metronidazol showed synergistic interactions in an in vitro trial. Co-amoxiclav with gentamicin, gentamicin with enrofloxacin, and metronidazole with enrofloxacin showed 100%, 80%, and 60% efficacy in treating clinical cases in field trials, respectively. As a result, the study came to the conclusion the higher prevalence of endometritis-based S. aureus, genetic host shifts, narrow options for single drugs, and need for novel drug combinations to treat clinical cases.

Genome-Wide Identification of MAPKK and MAPKKK Gene Family Members and Transcriptional Profiling Analysis during Bud Dormancy in Pear (Pyrus x bretschneideri)

The mitogen-activated protein kinase (MAPK) cascade consisting of three types of reversibly major signal transduction module (MAPKKK, MAPKK, and MAPK) is distributed in eukaryotes. MAPK cascades participate in various aspects of plant development, including hormone responses, cell division and plant dormancy. Pear is one of the most economically important species worldwide, and its yield is directly affected by dormancy. In this study, genome-wide identification of MAPKK and MAPKKK gene family members in Pyrus x bretschneideri and transcriptional expression analysis of MAPK cascades during pear dormancy were performed. We identified 8 MAPKKs (PbrMKKs) and 100 MAPKKKs (PbrMAPKKKs) in Pyrus using recent genomic information. PbrMAPKKs were classified into four subgroups based on phylogenetic analysis, whereas PbrMAPKKKs were grouped into 3 subfamilies (MEKK, Raf, and ZIK). Most PbrMAPKKKs and PbrMAPKKs in the same subfamily had similar gene structures and conserved motifs. The genes were found on all 17 chromosomes. The comprehensive transcriptome analysis and quantitative real-time polymerase chain reaction (qRT–PCR) results showed that numerous MAPK cascade genes participated in pear bud dormancy. The interaction network and co-expression analyses indicated the crucial roles of the MAPK member-mediated network in pear bud dormancy. Overall, this study advances our understanding of the intricate transcriptional control of MAPKKK-MAPKK-MAPK genes and provides useful information on the functions of dormancy in perennial fruit trees.

NASA GEOS Composition Forecast Modeling System GEOS-CF v1.0: Stratospheric Composition

The NASA Goddard Earth Observing System (GEOS) Composition Forecast (GEOS-CF) provides recent estimates and 5-day forecasts of atmospheric composition to the public in near-real time. To do this, the GEOS Earth system model is coupled with the GEOS-Chem tropospheric-stratospheric unified chemistry extension (UCX) to represent composition from the surface to the top of the GEOS atmosphere (0.01 hPa). The GEOS-CF system is described, including updates made to the GEOS-Chem UCX mechanism within GEOS-CF for improved representation of stratospheric chemistry. Comparisons are made against balloon, lidar, and satellite observations for stratospheric composition, including measurements of ozone (O₃) and important nitrogen and chlorine species related to stratospheric O₃ recovery. The GEOS-CF nudges the stratospheric O₃ toward the GEOS Forward Processing (GEOS FP) assimilated O₃ product; as a result the stratospheric O₃ in the GEOS-CF historical estimate agrees well with observations. During abnormal dynamical and chemical environments such as the 2020 polar vortexes, the GEOS-CF O₃ forecasts are more realistic than GEOS FP O₃ forecasts because of the inclusion of the complex GEOS-Chem UCX stratospheric chemistry. Overall, the spatial patterns of the GEOS-CF simulated concentrations of stratospheric composition agree well with satellite observations. However, there are notable biases-such as low NO _x and HNO₃ in the polar regions and generally low HCl throughout the stratosphere-and future improvements to the chemistry mechanism and emissions are discussed. GEOS-CF is a new tool for the research community and instrument teams observing trace gases in the stratosphere and troposphere, providing near-real-time three-dimensional gridded information on atmospheric composition.

Tomato SlBES1.8 Influences Leaf Morphogenesis by Mediating Gibberellin Metabolism and Signaling

Leaf morphogenetic activity determines its shape diversity. However, our knowledge of the regulatory mechanism in maintaining leaf morphogenetic capacity is still limited. In tomato, gibberellin (GA) negatively regulates leaf complexity by shortening the morphogenetic window. We here report a tomato BRI1-EMS-suppressor 1 transcription factor, SlBES1.8, that promoted the simplification of leaf pattern in a similar manner as GA functions. OE-SlBES1.8 plants exhibited reduced sensibility to exogenous GA3 treatment whereas showed increased sensibility to the application of GA biosynthesis inhibitor, paclobutrazol. In line with the phenotypic observation, the endogenous bioactive GA contents were increased in OE-SlBES1.8 lines, which certainly promoted the degradation of the GA signaling negative regulator, SlDELLA. Moreover, transcriptomic analysis uncovered a set of overlapping genomic targets of SlBES1.8 and GA, and most of them were regulated in the same way. Expression studies showed the repression of SlBES1.8 to the transcriptions of two GA-deactivated genes, SlGA2ox2 and SlGA2ox6, and one GA receptor, SlGID1b-1. Further experiments confirmed the direct regulation of SlBES1.8 to their promoters. On the other hand, SlDELLA physically interacted with SlBES1.8 and further inhibited its transcriptional regulation activity by abolishing SlBES1.8-DNA binding. Conclusively, by mediating GA deactivation and signaling, SlBES1.8 greatly influenced tomato leaf morphogenesis.

A9 SIALIC ACID METABOLISM PLAYS A KEY ROLE IN INTESTINAL FITNESS AND VIRULENCE OF AN ATTACHING/ EFFACING BACTERIAL PATHOGEN

Background

The gastrointestinal (GI) mucus barrier acts as an important interface between the host and luminal gut microbes, beyond its role in limiting direct contact between noxious luminal agents and the underlying intestinal epithelium. Mucus is comprised of highly glycosylated mucin proteins, modified by O-glycan side chains, formed by five sugar monomers, including sialic acid. Sialic acid frequently occupies the terminal position of O-glycans and can be cleaved by microbial sialidases. We hypothesize that upon entering their hosts, enteric pathogens, such as the attaching and effacing (A/E) family (EHEC, EPEC and Citrobacter rodentium) metabolically adapt to their intestinal environment, and express key virulence factors by sensing and metabolizing mucin sugars, such as sialic acid.

Aims

Investigate the role of sialic acid in regulating the fitness and virulence strategies of the A/E pathogen C. rodentium within the GI environment.

Methods

C57Bl/6 mice were orally infected with either wildtype (WT) or mutant strains of C. rodentium to study bacterial pathogenicity in vivo. Sialic acid was localized in mouse colonic tissue sections through lectin staining, and quantified in mouse feces and mucus scrapings using a commercial kit. Protein secretion by C. rodentium, in the presence or absence of sialic acid was analyzed by SDS-PAGE and mass spectrometry. Intestinal epithelial cell lines were infected with enteropathogenic E. coli (EPEC) or C. rodentium to examine bacterial adherence.

Results

Sialic acid was expressed widely in the GI tracts of mice, primarily in the colonic mucus layer and by intestinal goblet cells. Both EPEC and C. rodentium were found to take up and metabolize sialic acid through the transporter NanT. A C. rodentium strain deficient in sialic acid uptake ( ΔnanT) was dramatically impaired in colonizing the intestines of mice and was rapidly cleared. Sialic acid also impacted C. rodentium’s virulence by inducing the secretion of two key virulence factors, which significantly enhanced the pathogen’s adhesion to intestinal epithelial cells. Moreover, sialic acid increased C. rodentium’s ability to degrade mucus, due to the increased production of these two secreted virulence factors.

Conclusions

We demonstrate that sialic acid, a mucin-derived sugar, is an essential nutrient for A/E pathogens to thrive and expand within their host’s intestines. Moreover, sialic acid enhances pathogen virulence by inducing secretion of two important virulence factors, which increase adhesion to the epithelium and promote the degradation of mucus.

Funding Agencies

CCC, CIHRCH.I.L.D. Fdn

A fully noble metal-free electrocatalyst based on cobalt-polyoxometalate immobilized in layered double hydroxide for water oxidation at neutral pH

A POM-based immobilized catalyst [PCoW11O39]5-/Tris-LDH, devoid of any noble metal, as an efficient and durable electrocatalyst for water oxidation at neutral pH. Multiple lines of experimental evidence confirm that the...

Acute and subacute toxicity study of Aucklandia lappa Decne seed oil

Purpose: To investigate the acute and subacute toxicity of Aucklandia lappa Decne. seed oil (ALDO) in mice and rats.Methods: A single dose of 10 g ALDO/kg was administered to Kunming mice in an acute oral toxicity experiment. Their weight and feed consumption were recorded for 14 days to observe whether they had symptoms of poisoning and mortality. Sprague-Dawley (SD) rats were administered 0.89, 1.77 and 3.54 g/kg for 28 days, and symptoms of poisoning and mortality were monitored daily. Body weight, feedconsumption, hematology, serum biochemical parameters, relative organ weight, and histopathology of the experimental and control groups were compared.Results: The acute oral toxicity study revealed that there was no significant difference in the macroscopic results, including mortality, feed consumption and weight growth between the group dosed with 10 g ALDO/kg (p > 0.05) and the control group. In the subacute toxicity test, SD rats had a higher weight growth rate and feed utilization after doses of 0.89 g ALDO/kg (p < 0.01). However, compared with the control group (p > 0.05), there was also no significant difference in biochemical and hematological parameters, relative organ weight, or in macroscopic and histological features of both animal types. The electrolyte concentrations of Na and Cl increased at the doses of 1.77 and 3.54 g/kg (p < 0.01).Conclusion: These results suggest that ALDO is relatively safe when administered orally to rats and provide a theoretical basis for the development of new food resources.

Downregulation of lncRNA PpL-T31511 and Pp-miRn182 Promotes Hydrogen Cyanamide-Induced Endodormancy Release through the PP2C-H2O2 Pathway in Pear (Pyrus pyrifolia)

Bud endodormancy is an important, complex process subject to both genetic and epigenetic control, the mechanism of which is still unclear. The endogenous hormone abscisic acid (ABA) and its signaling pathway play important roles in the endodormancy process, in which the type 2C protein phosphatases (PP2Cs) is key to the ABA signal pathway. Due to its excellent effect on endodormancy release, hydrogen cyanamide (HC) treatment is considered an effective measure to study the mechanism of endodormancy release. In this study, RNA-Seq analysis was conducted on endodormant floral buds of pear (Pyrus pyrifolia) with HC treatment, and the HC-induced PP2C gene PpPP2C1 was identified. Next, software prediction, expression tests and transient assays revealed that lncRNA PpL-T31511-derived Pp-miRn182 targets PpPP2C1. The expression analysis showed that HC treatment upregulated the expression of PpPP2C1 and downregulated the expression of PpL-T31511 and Pp-miRn182. Moreover, HC treatment inhibited the accumulation of ABA signaling pathway-related genes and hydrogen peroxide (H₂O₂). Furthermore, overexpression of Pp-miRn182 reduced the inhibitory effect of PpPP2C1 on the H₂O₂ content. In summary, our study suggests that downregulation of PpL-T31511-derived Pp-miRn182 promotes HC-induced endodormancy release in pear plants through the PP2C-H₂O₂ pathway.

Core-shell NaErF4@NaYF4 upconversion nanoparticles qualify as a NIR speckle wavemeter for a visible CCD

Speckle patterns have been widely employed as a method for precisely determining the wavelength of monochromatic light. In order to achieve higher wavelength precision, a variety of optical diffusing waveguides have been investigated with a focus on their wavelength sensitivity. However, it has been a challenge to find a balance among the cost, compactness, precision, and stability of the waveguide. In this work, we designed a compact cylindrical random scattering waveguide (CRSW) as the light diffuser by mixing TiO₂ particles and ultra-violate adhesive. In the CRSW, speckle patterns are generated by input light scattering off TiO₂ particles multiple times. Additionally, a thin layer of upconversion nanoparticles (UCNPs) was sprayed on the end face of CRSW to allow near-infrared (NIR) light to be converted to visible light, breaking the imaging limitations of visible cameras in the NIR range. We, then, further designed a convolution neural network (CNN) to recognize the wavelength of the speckle patterns with excellent robustness and ability to transfer learning. This resulted in the achievement of a high wavelength precision of 20 kHz (∼0.16 fm) at around 1550 nm with a temperature resistance of ±2 °C. Our results demonstrate a low-cost, compact, and simple NIR wavemeter, which is capable of ultra-high wavelength precision and good temperature stability. It has significant value for applications in high-speed and high-precision laser wavelength measurements.

[Comparison of different evaluation systems for assessing disease severity and treatment efficacy in patients with chronic obstructive pulmonary disease]

OBJECTIVE

To compare the practicability and clinical value of different evaluation systems for assessing disease severity and treatment efficacy in patients with chronic obstructive pulmonary disease (COPD).

METHODS

We retrospectively analyzed the clinical data of 28 patients with acute exacerbation of COPD admitted to our hospital between November, 2020 and January, 2021. All the patients were assessed with percentage of predicted forced expiratory volume in 1 second (FEV1% pred), COPD assessment test (CAT), modified British Medical Research Council (mMRC), baseline dyspnea index (BDI), clinical COPD questionnaire (CCQ), St. George's respiratory questionnaire (SGRQ), BODE index, Hamilton Depression Rating Scale (HDRS) at admission and with CAT, mMRC, transition dyspnea index (TDI), CCQ, SGRQ, and HDRS at 1 month after discharge. The correlations among FEV1% pred, CAT, mMRC, BDI, CCQ, SGRQ, BODE and HDRS at admission were analyzed. We also compared the TDI and scores of CAT, mMRC, CCQ, SGRQ, and HDRS at 1 month after discharge among the patients using single (n=8), dual (n=10) or triple inhaled medications (n=10) after discharge.

RESULTS

Among these patients, FEV1% pred was moderately correlated with SGRQ and BDI (r=-0.66, r=0.61; P < 0.01), and CCQ activity score was closely correlated with mMRC, SGRQ activity score and BDI (r=0.82, r=0.92, r=-0.89; P < 0.01). SGRQ activity score was closely correlated with mMRC and BDI (r=0.84, r=-0.91; P < 0.01), and SGRQ symptom score was closely correlated with BODE (r=0.80, P < 0.01). SGRQ impact score was moderately correlated with HDRS (r=0.57, P < 0.01). In all the 28 patients, all the evaluation scores except for CCQ mental score and HDRS improved significantly after treatment (P < 0.05). At 1 month after discharge, CCQ total score decreased significantly in single therapy group (P < 0.05); CAT, mMRC, CCQ and SGRQ improved obviously in dual therapy group (P < 0.05); CCQ and SGRQ scores decreased significantly in triple therapy group (P < 0.05); the TDI did not differ significantly among the 3 groups (P>0.05).

CONCLUSION

For patients with COPD, BDI and TDI are recommended over mMRC for assessing dyspnea. CAT, CCQ and SGRQ allow sensitive assessment of the treatment efficacy to serve as routine evaluation tests, and among them SGRQ is the most comprehensive and is thus recommended when sufficient time is allowed. BODE is relatively complex but highly valuable for predicting the patients'survival outcomes. HDRS is recommended for routine screening of depression in patients with COPD.

Genome-wide analysis of long noncoding RNAs affecting floral bud dormancy in pears in response to cold stress

The versatile role of long noncoding RNAs (lncRNAs) in plant growth and development has been established, but a systematic identification and analysis of lncRNAs in the pear has not been reported. Bud dormancy is a crucial and complicated protective mechanism for plants in winter. The roles of lncRNAs in the dormancy process remain largely unclear. In this study, we induced pear floral buds to enter into different dormant statuses by simulating four different chilling accumulation conditions. Then, a time series of RNA-seq analysis was performed and we identified 7594 lncRNAs in Pyrus pyrifolia (Burm. F.) Nakai that have not been identified. The sequence and expression of the lncRNAs were confirmed by PCR analysis. In total, 6253 lncRNAs were predicted to target protein-coding genes including 692 cis-regulated pairs (596 lncRNAs) and 13,158 trans-regulated pairs (6181 lncRNAs). Gene Ontology analysis revealed that most of lncRNAs' target genes were involved in catalytic activity, metabolic processes and cellular processes. In the trend analysis, 124 long-term cold response lncRNAs and 80 short-term cold response lncRNAs were predicted. Regarding the lncRNA-miRNA regulatory networks, 59 lncRNAs were identified as potential precursors for miRNA members of 20 families, 586 lncRNAs were targets of 261 pear miRNAs and 53 lncRNAs were endogenous target mimics for 26 miRNAs. In addition, three cold response lncRNAs, two miRNAs and their target genes were selected for expression confirmed. The trend of their expression was consistent with the predicted relationships among them and suggested possible roles of lncRNAs in ABA metabolic pathway. Our findings not only suggest the potential roles of lncRNAs in regulating the dormancy of pear floral buds but also provide new insights into the lncRNA-miRNA-mRNA regulatory network in plants.

[A real-world study of 176 cases with aplastic anemia treated in outpatient]

目的

探索真实世界门诊治疗再生障碍性贫血（AA）患者的诊断流程、治疗及疗效。

方法

评估2018年1月至2019年12月门诊治疗176例AA患者的诊断流程、治疗方案及疗效。

结果

患者出现症状至首次就诊中位时间7（5～120）个月，就诊原因包括出血（52.3%）、贫血（51.7%）、感染（6.8%）。诊断流程中168例（95.5%）患者完成髂骨骨髓穿刺（骨穿），仅22例（17.1%）完善了多部位骨穿（胸骨分类）；骨髓活检完成率85.1%（143/168）；只有59.5%（100/168）和58.9%（99/168）完成了骨髓流式免疫分型及染色体核型分析；86例（48.5%）完成阵发性睡眠性血红蛋白尿（PNH）克隆筛查；造血祖细胞培养检查完成率最低，仅45例（26.8%）。环孢素A（CsA）联合雄激素及左旋咪唑为最常见治疗方案，总计77例（43.8%），其次为CsA联合雄激素45例（25.6%），单用CsA者24例（13.6%），单用雄激素者16例（9.1%），14例（7.9%）患者确诊后选择中药或未治疗。根据门诊复诊频率将176例患者分为复诊规律组（每年≥4次）130例（73.9%）和复诊欠规律组（每年<4次）46例（26.1%）。复诊规律组6个月有效率较高（52.5%对28.0%，P＝0.005），12个月高质量缓解率更好（40.7%对16.7%，P＝0.027），24个月复发率更低（4.4%对36.4%，P＝0.001）。

结论

真实世界治疗的AA患者诊断流程需重视多部位骨穿检查并完成PNH克隆筛查、流式免疫分型、染色体核型分析及造血祖细胞培养检查；门诊规律复诊患者可获得高质量缓解，复发率低，推荐每年至少复诊4次。

Definition and review on a category of long non-coding RNA: Atherosclerosis-associated circulating lncRNA (ASCLncRNA)

Atherosclerosis (AS) is one of the most common cardiovascular system diseases which seriously affects public health in modern society. Finding potential biomarkers in the complicated pathological progression of AS is of great significance for the prevention and treatment of AS. Studies have shown that long noncoding RNAs (lncRNAs) can be widely involved in the regulation of many physiological processes, and have important roles in different stages of AS formation. LncRNAs can be secreted into the circulatory system through exosomes, microvesicles, and apoptotic bodies. Recently, increasing studies have been focused on the relationships between circulating lncRNAs and AS development. The lncRNAs in circulating blood are expected to be new non-invasive diagnostic markers for monitoring the progression of AS. We briefly reviewed the previously reported lncRNA transcripts which related to AS development and detectable in circulating blood, including ANRIL, SENCR, CoroMarker, LIPCAR, HIF1α-AS1, LncRNA H19, APPAT, KCNQ1OT1, LncPPARδ, LincRNA-p21, MALAT1, MIAT, and UCA1. Further researches and a definition of atherosclerosis-associated circulating lncRNA (ASCLncRNA) were also discussed.

Correlations of the expression of γδ T cells and their co-stimulatory molecules TIGIT, PD-1, ICOS and BTLA with PR and PIBF in the peripheral blood and decidual tissues of women with unexplained recurrent spontaneous abortion

Semi-allogeneic embryos are not rejected by the maternal immune system due to maternal-fetal immune tolerance. Progesterone (P) receptor (PR)-expressing γδ T cells are present in healthy pregnant women. In the presence of P, these cells secrete an immunomodulatory protein called progesterone-induced blocking factor (PIBF), which can facilitate immune escape and is important in preventing embryonic rejection. This work investigated the correlations of the expression of γδ T cells and their co-stimulatory molecules T cell immunoglobulin and ITIM domain (TIGIT), programmed cell death 1 (PD-1), inducible co-stimulator (ICOS) and B and T lymphocyte attenuator (BTLA) with progesterone receptor (PR) and progesterone-induced blocking factor (PIBF) in peripheral blood and decidual tissue in women with unexplained recurrent spontaneous abortion (URSA) and normal pregnant (NP) women. We confirmed that γδ T cell proportions and PIBF expression in the peripheral blood and decidua of URSA women decreased significantly, while PR expression in decidua decreased. However, TIGIT, PD-1, ICOS and BTLA expression in γδ T cells in peripheral blood did not change, while TIGIT and PD-1 expression in γδ T cells in decidua increased significantly. Under the action of PHA-P (10 µg/ml), co-blocking of TIGIT (15 µg/ml) and PD-1 (10 µg/ml) antibodies further induced γδ T cell proliferation, but PIBF levels in the culture medium supernatant did not change. At 10^-10 M P, γδ T cells proliferated significantly, and PIBF concentrations in the culture medium supernatant increased. γδ T cells co-cultured with P, TIGIT and PD-1 blocking antibodies showed the most significant proliferation, and PIBF concentrations in the culture medium supernatant were the highest. These results confirm that P is necessary for PIBF production. The TIGIT and PD-1 pathways participate in γδ T cell proliferation and activation and PIBF expression and play important roles in maintaining pregnancy.

Light quality affects the proliferation of in vitro cultured plantlets of Camellia oleifera Huajin

Background

Camellia oleifera is an important oil-yielding woody plant native to China. Tea oil extracted from the seeds is rich in health-beneficial compounds. Huajin is a high-yielding elite variety of C. oleifera, with large fruits and remarkable resilience, widely cultivated in southern China; however, its seedling quality tends to be uneven. At present, techniques such as grafting, and cuttings are primarily adopted to propagate C. oleifera. These approaches are susceptible to environmental constraints owing to the long growth period, resulting in the lack of C. oleifera seedlings. Methods to make the cultivation more economical are warranted; this can be facilitated by tissue culture technology to provide good-quality seedlings in a short time.

Methods

In vitro cultured plantlets of C. oleifera Huajin were exposed to red light (RL), blue light (BL), red:blue light at a 4:1 ratio (R4:B1), and red:blue light at a 1:4 ratio (R1:B4); white light (WL) was used as the control treatment. To investigate the influence of light spectral quality on the proliferation coefficient, photosynthetic pigments, soluble proteins, plant height, leaf shape, Rubisco enzyme activity, and stomata and leaf anatomical features.

Results

The highest proliferation coefficient was observed under combined red and blue (4:1) light. In addition, this treatment resulted in the second highest chlorophyll content, the thickest palisade and spongy tissues, and consequently, the thickest leaves. The same treatment resulted in the second highest stomatal density, albeit concomitantly with the smallest average stomatal length and width.

Discussion

These results indicate that high-quality propagation of Huajin shoots can be achieved by culturing the plants in vitro under a combination of red and blue (4:1) lights. Previous studies have shown that red and blue lights improve rooting and transplanting rates of tissue culture seedlings. Hence, future research should focus on the effect of light quality on rooting and transplanting of tissue culture plantlets of Huajin and its specific molecular mechanisms.

The effect of Clostridium tyrobutyricum Spo0A overexpression in the intestine of mice

Clostridium tyrobutyricum shows probiotic properties and can affect the composition of gut microbiota and regulate the intestinal immune system. Compared with other probiotics, this spore-producing bacterium shows unparalleled advantages in commercial production. In addition to being resistant to extreme living environments for extended periods, its endophytic spores are implicated in inhibiting cancer cell growth. We speculated that C. tyrobutyricum spores can also promote gut health, which mean it can maintain intestinal homeostasis. To date, the beneficial effects of C. tyrobutyricum spores on gut health have not been reported. In this study, a Spo0A-overexpressing C. tyrobutyricum strain was developed to increase spore production, and its probiotic effects on the gut were assessed. Compared with the wild-type, the engineered strain showed significantly increased sporulation rates. Mice administered with the engineered strain exhibited enhanced intestinal villi and the villus height/crypt depth ratio, weight gain and improved Firmicutes/Bacteroidetes ratio to facilitate intestinal homeostasis. This study demonstrated for the first time that enhanced spore production in C. tyrobutyricum can improve intestinal homeostasis, which is advantageous for its commercial application in food and pharmaceutical industry.

AB0691 CHARACTERIZATION OF DIFFERENT GROUPS WITH IMAGING AND NON-IMAGING FINDINGS OF ANKYLOSING SPONDYLITIS COMBINE WITH HIP LESION IN WESTERN CHINESE

Background:

Hip joint lesion are the main cause of disability in patients with Ankylosing Spondylitis(AS) in western China. Seriously affect the quality of life of patients.The early clinical characteristics of hip joint disease are not typical, the disease is insidious, and the radiological diagnosis is delayed.The main prevention is early screening and early diagnosis.

Objectives:

This study attempted to find out the main characteristics and related factors in different groups of AS combine with hip joint lesion in western China.

Methods:

A-First evaluation:How many patients have 1) active SIJ changes on MRI. 2) chronic SIJ changes (each for erosion, clerosis, ankylosis, or any of those) on MRI. 3) a combination of active changes and chronic changes (each for erosion, sclerosis, ankylosis, or any of those) on MRI. 4) active hip changes on MRI. 5) chonic hip changes (erosion, effusion any of those) on MRI. 6) a combination of active changes and chronic hanges (erosion, effusion any of those) on MRI. B-Then, combination SIJ / hip. 7) active SIJ changes on MRI and in parallel active hip changes on MRI. 8) chronic (see above) SIJ changes on MRI and in parallel active hip changes on MRI. 9) chronic (see above) SIJ changes on MRI and in parallel chronic (see above) hip changes on MRI. 10) chronic (see above) SIJ changes on MRI and in parallel any (active or chronic) hip changes on MRI. C-Then, characterization of these groups with non-imaging findings. Characteristics of groups 7-10 above, for age, sex, Disease duration, Hip pain, Joint pain, enthesitis, Diarrhea, uveitis, ASDAS-CRP, BASDAI, BASFI, BASMI, Pat. Global, CRP, ESR, Harris Score, HLA-B27.

Results:

Retrospective analysis total 558 SpA patients (mean age 29, mean duration 5 years). 1) HIP-Active+Chronic group (N=288, AS=151) vs SIJ+HIP-Active group (N=241, AS=138): hip pain (p<0.0001), diarrhea (p<0.0001), joint pain (p<0.0001) and BASFI (p<0.05); 2) HIP-Active+Chronic(N=117, AS=58) vs SIJ-Chronic+HIP-Active group (N=214, AS=134): hip pain(p<0.0001), joint pain (p<0.0001), enthesitis (p<0.0001), ASDAS-CRP (p<0.05) and ESR (p<0.05); 3) SIJ-Active+Chronic group (N=204, AS=125) vs SIJ-Chronic+HIP-Active group (N=214, AS=134): hip pain (p<0.0001), joint pain (p<0.0001); 4) SIJ-Active+Chronic group (N=204, AS=125) vs SIJ+HIP-Chronic group (N=72, AS=40):hip pain (p<0.0001), Pat. Global (p<0.05); 5) SIJ+HIP-Active group (N=241, AS=138) vs SIJ-Chronic+HIP-Active group (N=214, AS=134): HLA-B27 positive (Chi-square, df, 24.98, 4) (p<0.0001); 6) SIJ+HIP-Chronic group (N=72, AS=40) vs SIJ-Chronic+HIP-Active/Chronic group (N=228, AS=144): Pat. Global (p<0.05), ESR (p<0.05).

Conclusion:

Hip joint lesion are closely related to sacroiliac joint lesion and HLA-B27 positive in AS. Hip pain is the main clinical manifestation of hip joint lesion in AS. Hip joint lesion may lead to function declines, disease activity in AS.

References:

[1]Vander C B, Munoz-Gomariz E, Font P, et al. Hip involvement in ankylosing spondylitis:epidemiology and risk factors associated with hip replacement surgery[J]. Rheumatology (Oxford), 2010,49(1):73-81.

[2]Sieper J, Rudwaleit M, Baraliakos X, et al. The Assessment of SpondyloArthritis international Society (ASAS) handbook: a guide to assess spondyloarthritis[J]. Ann Rheum Dis, 2009,68 Suppl 2:i1-i44.

[3]Ward M M, Deodhar A, Akl E A, et al. American College of Rheumatology/Spondylitis Association of America/Spondyloarthritis Research and Treatment Network 2015 Recommendations for the Treatment of Ankylosing Spondylitis and Nonradiographic Axial Spondyloarthritis[J]. Arthritis Rheumatol, 2016,68(2):282-298.

Disclosure of Interests:

Qing Han: None declared, Zhaohui Zheng: None declared, Kui Zhang: None declared, Zheng Yu: None declared, Fengfan Yang: None declared, Qiang Liang: None declared, Ping Zhu: None declared, Xenofon Baraliakos Grant/research support from: Grant/research support from: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Consultant of: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Speakers bureau: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen

SAT0563 SINGLE-PHOTON EMISSION COMPUTED TOMOGRAPHY-COMPUTED TOMOGRAPHY IS EQUIVALENT TO MAGNETIC RESONANCE IMAGING IN THE EARLY DIAGNOSIS OF SPONDYLOARTHRITIS: A RETROSPECTIVE STUDY

Background:

SpA has historically been a difficult clinical diagnosis, especially early diagnosis. Two imaging techniques that address this problem are magnetic resonance imaging (MRI) and Single-Photon Emission Computed Tomography-Computed Tomography (SPECT-CT). Their accuracies have not been adequately compared.

Objectives:

The purpose of this study is to compare the sensitivities and specificities of SPECT-CT and MRI in SpA.

Methods:

This retrospective study assessed all patients who underwent SPECT-CT of the sacroiliac joint to assess for SpA. The results of SPECT-CT were compared against MRI for all patients in the cohort who underwent an MRI within 4 weeks of the SPECT-CT. A diagnosis of SpA in the discharge summary was considered the reference standard, and was based on a combination of clinical scenario, response to therapy, imaging,, patient history or lab index.

Results:

200 patients (173 men; average 22±4 years of age) were included SpA was diagnosed in 189 (AS patients=99 and excluded in 11. SPECT-CT and MRI had similar (P >0 .05;k ¼ 0.74) sensitivities (0.94 vs 0.94),specificities (1.00 vs 1.00),positive predictive values (1.00 vs 1.00),negative predictive values (0.94 vs 0.80),and accuracies (0.97 vs 0.95) when compared to the reference standard.

Conclusion:

Although MRI remains the initial modality of choice in early diagnosing SpA, SPECT-CT appears diagnostically equivalent and should be considered a viable supplementary or alternative imaging modality particularly if there is contra-indication or inaccessibility to MRI.

References:

[1]Taurog J D, Chhabra A, Colbert R A. Ankylosing Spondylitis and Axial Spondyloarthritis[J]. N Engl J Med, 2016,375(13):1303.

[2]van der Linden S, Valkenburg H A, Cats A. Evaluation of diagnostic criteria for ankylosing spondylitis. A proposal for modification of the New York criteria[J]. Arthritis Rheum, 1984,27(4):361-368.

[3]Ward M M, Deodhar A, Gensler L S, et al. 2019 Update of the American College of Rheumatology/Spondylitis Association of America/Spondyloarthritis Research and Treatment Network Recommendations for the Treatment of Ankylosing Spondylitis and Nonradiographic Axial Spondyloarthritis[J]. Arthritis Rheumatol, 2019,71(10):1599-1613.

[4]Boonen A, Sieper J, van der Heijde D, et al. The burden of non-radiographic axial spondyloarthritis[J]. Semin Arthritis Rheum, 2015,44(5):556-562.

[5]Sieper J, Rudwaleit M, Baraliakos X, et al. The Assessment of SpondyloArthritis international Society (ASAS) handbook: a guide to assess spondyloarthritis[J]. Ann Rheum Dis, 2009,68 Suppl 2:i1-i44.

[6]Bermo M, Behnia S, Fair J, et al. Review of Extraskeletal Activity on Tc-99m Methylene Diphosphonate Bone Scintigraphy and Value of Cross-Sectional and SPECT-CT Imaging Correlation[J]. Curr Probl Diagn Radiol, 2018,47(5):324-332.

[7]Ward M M, Deodhar A, Akl E A, et al. American College of Rheumatology/Spondylitis Association of America/Spondyloarthritis Research and Treatment Network 2015 Recommendations for the Treatment of Ankylosing Spondylitis and Nonradiographic Axial Spondyloarthritis[J]. Arthritis Rheumatol, 2016,68(2):282-298.

[8]Abdelhafez Y G, Hagge R J, Badawi R D, et al. Early and Delayed 99mTc-MDP SPECT/CT Findings in Rheumatoid Arthritis and Osteoarthritis[J]. Clin Nucl Med, 2017,42(11):e480-e481.

Figure 1.

An 20-years-old man with 5 years of low back pain and spine malformation. (A) SPECT-CT showed an abnormal concentration of radioactivity in SIJ. (B–C) In SIJ, MRI showed a high signal on T1-WI, and a high signal on STIR.

Figure 2.

An 37-year-old man with 20 years of low back pain and spine malformation. (A) SPECT-CT showed an abnormal concentration of radioactivity in SIJ. (B–C) In SIJ, MRI showed a high signal on T1-WI, and a low signal on STIR.

Disclosure of Interests:

Qing Han: None declared, Zhaohui Zheng: None declared, Kui Zhang: None declared, Zheng Yu: None declared, Fengfan Yang: None declared, Qiang Liang: None declared, Ping Zhu: None declared, Xenofon Baraliakos Grant/research support from: Grant/research support from: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Consultant of: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Speakers bureau: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen

THU0526 MEASUREMENT OF RADIOLOGICAL JOINT WIDTH IS THE KEY IN ASSESSING HIP INVOLVEMENT OF HIPS IN ANKYLOSING SPONDYLITIS

Background:

Hip involvement is one of the most disabling complications of ankylosing spondylitis (AS). Frequently, arthroplasty is necessary by the time symptoms appear.

Objectives:

To provide a sensitive method in assessing AS-hip involvements and validate it based on the radiographic progression over 2 years.

Methods:

Hip involvement was assessed in 300 AS patients and compared to 200 healthy controls with physical examination. Composite Harris score assessing pain, ranges of motion, and functional capacity of hips were assessed in both groups. Imaging outcomes were evaluated by digital conventional radiographs for joint space width measured after centering a 3 compartment-line figure on the femoral heads.

Results:

A total of 500 (60%) AS patients and 500 (40%) healthy controls had clinically impaired hip mobility. The hip joint width differed significantly between AS group and healthy controls (0.93±0.54, range 5.41-0.35vs 4.83±0.74, range 6.72-3.56, P<0.0001). Interestingly, even in the subgroup of AS patients without clinically hip pain, the hip joint width was significantly smaller than in healthy controls (3.29±0.66, range 5.4-2.1 vs 4.83±0.74, range 6.72-3.56, P<0.0001). We then evaluated the MRI images of the same 300 subjects. First, we evaluated the 200 control subjects to establish a threshold. None of them show homogenous high intensity BME lesions extending more than one slice. we examine the MRI of the 300 AS patients. Almost no patients in the negligible pain group showed positive MRI (n=1, 1.2%). Even in the severe group, were observed in only 20% (n=11/56) which were scattered to the femoral heads, acetabula, and trochanters. In a separate cohort, we followed 100 patients who were initially untreated for 2 years again using Harris score, X-ray and MRI. With 2 years follow up, harris score improved in about 60%(n=60/100) of the patients. Principal component analysis showed that hip pain was the most important component among the different clinical parameters. Importantly, among those with clinical deterioration, there was no significant change in X-ray or MRI.

Conclusion:

Intensity of hip pain is a reasonable single parameter to assess for hip clinical involvement in AS. The higher the hip pain, the narrower the hip joint width. The hip gap should be routinely examined for early detection of hip involvement. Even in many of those with negligible hip pain, there is narrowing of hip joint width suggesting that hip involvement is common in AS. Hip disease progresses very slowly over 2 years.

References:

[1]KIRSTEN MACKAY, CHRISTOPHER MACK, SINEAD BKOPHY.et al. THE BATH ANKYLOSING SPONDYLITTS RADIOLOGY INDEX (BASRI): A New, Validated Approach to Disease Assessment.[J] ARTHRITIS & RHEUMATISM. l998(41), pp 2263-2270.

[2]MacKay K, Brophy S, Mack C, Doran M, Calin A.The development and validation of a radiographic grading system for the hip in ankylosing spondylitis: the bath ankylosing spondylitis radiology hip index. [J] J Rheumatol. 2000 Dec;27(12):2866-72.

[3]Julie C, Baker-LePain, Nancy E. Lane.Relationship between joint shape and the development of osteoarthritis. Curr Opin Rheumatol. [J] 2010; 22(5): 538–543.

[4]Zhen Guo, Huang, Xue Zhe, Zhang, Wen Hong. et al. The application of MR imaging in the detection of hip involvement in patients with ankylosing spondylitis.[J] European journal of radiology. 2013;82(9):1487-1493.

[5]M. Konsta & P. P. Sfikakis & V. K. Bournia.et al. Absence of radiographic progression of hip arthritis during infliximab treatment for ankylosing spondylitis. [J] Clin Rheumatol 2013; (32):1229–1232.

[6]Hyemin Jeong, Yeong Hee Eun, In Young Kim.et al. Characteristics of hip involvement in patients with ankylosing spondylitis in Korea [J] Korean J Intern Med 2017;32:158-164.

Acknowledgments:

Professor David Yu

Disclosure of Interests:

Qing Han: None declared, Zhaohui Zheng: None declared, Kui Zhang: None declared, Zheng Yu: None declared, Fengfan Yang: None declared, Qiang Liang: None declared, Ping Zhu: None declared, Xenofon Baraliakos Grant/research support from: Grant/research support from: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Consultant of: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen, Speakers bureau: AbbVie, BMS, Celgene, Chugai, Merck, Novartis, Pfizer, UCB and Werfen

[Treatment of Chilomastix mesnili infection with traditional Chinese medicine: a case report]

This paper reports a case with Chilomastix mesnili infections, and summarizes the diagnosis and treatment with traditional Chinese medicine.

A51 UTILIZING MUCIN-DERIVED SUGARS CONFERS A FITNESS ADVANTAGE TO THE ENTERIC PATHOGEN CITROBACTER RODENTIUM THAT PROMOTES INTESTINAL COLONIZATION

Background

Citrobacter rodentium is an enteric murine pathogen used to model the human diarrheal pathogens. Following inoculation, C. rodentium colonizes the mouse cecum where it expands and ultimately spreads to the distal colon. During this process, C. rodentium has to compete with commensal microbes for available nutrients. Moreover, to spread throughout the gut, and infect the intestinal epithelium, C. rodentium has to cross through, and or dwell within the intestinal mucus layer which is composed of the heavily glycosylated protein Muc2. Muc-2 is glycosylated and coated by 5 distinct terminal sugar residues: galactose, N-acetylgalactosamine, N-acetylglucosamine, fucose, and sialic acid. Many commensal microbes have the ability to cleave and free these sugars from the Muc2 protein, releasing them for their own consumption, however pathogens appear to exploit this process. While studies have indicated that C. rodentium uses these terminal sugar residues as a nutritional source, their relative importance in the pathogenic strategy of C. rodentium (and other gut pathogens) remains unclear

Aims

Investigate the role played by mucin sugar residues in controlling C. rodentium pathogenesis

Methods

Deletions of agaW, nagE, mglB, galP, fucK, and nanT were generated on the chromosome of C. rodentium (Strepr) by overlap extension PCR. Growth assays were performed to examine the growth kinetics of mutants C. rodentium in minimal (M9) media supplemented with one of the 5 mucin sugars or M9 with whole mucin as control. Specific pathogen free (SPF) C57BL/6 mice, or germfree C57BL/6 mice were orally gavaged with wildtype C. rodentium (Strepr) or one of ΔagaW, ΔnagE, ΔmglB, ΔgalP, ΔfucK, or ΔnanT strains. Mice were euthanized at 6 days post-infection, and the cecum, colon, and spleen were collected and histologically scored for pathology and intestinal and systemic bacterial burden. Stool samples were collected throughout the 6 days to quantify C. rodentium burdens

Results

Growth assays confirmed that the specific sugar transporter/kinase mutant C. rodentium strains grew normally when placed in media supplemented with whole mucin, or with most sugars, only showing overt defects in growth when solely supplemented with the sugar for which they were impaired. Several of the C. rodentium mutants including ΔnanT showed overt defects in colonization/infection of SPF C57BL/6 mice, but their pathogenesis was normalized in germfree mice, or in mice treated with the antibiotic streptomycin at each day post-infection. These findings indicate that the impact of mucin sugar utilization on C. rodentium virulence is microbiota-dependent

Conclusions

C. rodentium uses mucin sugars as nutrient source in the mouse gut, and an inability to use these sugars impairs their ability to infect their hosts in a microbiota dependent manner

Funding Agencies

CAG, CCC, CIHR, NRC

Comparison of Different Slice Thicknesses in Computed Tomography for Labyrinthine Fistula Evaluation

OBJECTIVES

The aim of the present study is to assess the impact of different slice thicknesses in computed tomography for labyrinthine fistula evaluation and to determine the appropriate slice thickness.

METHODS

A total of 258 patients who underwent mastoidectomy and tympanoplasty for chronic otitis media with cholesteatoma from 2010 to 2014 were reviewed. The radiological diagnoses were compared with intraoperative findings. Sensitivity and specificity of 2.0-, 1.5-, 1.0-, and 0.75-mm-thick computed tomographic (CT) images for the evaluation of labyrinthine fistulae were calculated. Cohen's κ coefficient was also calculated.

RESULTS

The sensitivities of 2.0-, 1.5-, 1.0-, and 0.75-mm-thick CT images for the evaluation of labyrinthine fistulae were 76.9, 86.5, 90.4, and 93.3% (observer 1) and 67.3, 76.0, 79.8, and 87.5% (observer 2), respectively. The specificities of 2.0-, 1.5-, 1.0-, and 0.75-mm-thick CT images for labyrinthine fistula evaluation were 96.1, 94.8, 95.5, and 95.5% (observer 1) and 99.4, 97.4, 95.5, and 94.8% (observer 2), respectively. Cohen's κ coefficients were 0.790, 0.788, 0.876, and 0.911 in 2.0-, 1.5-, 1.0-, and 0.75-mm-thick CT images, respectively.

CONCLUSIONS

The sensitivity of CT for labyrinthine fistula evaluation increases with decreasing slice thickness, while the specificity does not improve.

Cell-free Mycobacterium tuberculosis DNA test in pleural effusion for tuberculous pleurisy: a diagnostic accuracy study

OBJECTIVES

Tuberculous pleurisy (TP) diagnosis remains difficult, with the sensitivity of Xpert MTB/RIF (Xpert) and mycobacterial culture (culture) only about 30-50%. We aimed to assess the diagnostic performance of a cell-free Mycobacterium tuberculosis DNA test (cf-TB) in pleural effusion for TP.

METHODS

Adults (≥18 years) with suspected TP presenting with pleural effusion were consecutively recruited, and pleural effusion specimens were prospectively collected in Beijing Chest Hospital, Beijing, China. After centrifuging pleural effusion, sediments were used for culture, Xpert and T-SPOT.TB assay, whereas supernatants were used for cf-TB and adenosine deaminase assay. The diagnostic performance was assessed against a composite reference standard.

RESULTS

From June 2015 to December 2018, we prospectively evaluated 286 adults with suspected TP. One hundred twenty-two participants were classified as definite TP based on the prespecified composite reference standard. The cf-TB produced a sensitivity of 79.5% (97/122, 95% confidence interval (CI) 72.4- 86.7) for definite TP, which was superior to Xpert (38.5% (29.9-47.2); 47/122; p < 0.001) and culture (27.1% (19.2-34.9); 33/122; p < 0.001). With pleural effusion Xpert and/or culture as the reference standard, cf-TB showed 96.6% (57/59, 95% CI 92.0-100.0) sensitivity, which was also significantly higher than Xpert (79.7%, 95% CI 69.4-89.9; 47/59; p 0.004) and culture (55.9%, 95% CI: 43.3-68.6; 33/59; p < 0.001).

CONCLUSIONS

The cf-TB clearly showed improved sensitivity compared with Xpert and culture. We recommend cf-TB as the first-line test for TP diagnosis.

Study on Antibacterial and Quorum-Sensing Inhibition Activities of Cinnamomum camphora Leaf Essential Oil

Many essential oils (EOs) regulate the quorum-sensing (QS) system of pathogens and inhibit the virulence expression. Interference with QS can potentially reduce bacterial multidrug resistance and aid the biological control of bacterial disease. In the present work, the antibacterial and anti-QS activities of Cinnamomum camphora leaf EO were investigated. A total of 23 chemical components with relative levels ≥0.11%, including a large number of terpene compounds, were identified in C. camphora leaf EO by gas chromatography-mass spectrometry (GC-MS). The principal component was linalool, followed by eucalyptol, with relative levels of 51.57% and 22.07%, respectively. The minimum inhibitory concentration (MIC) and antibacterial activity of C. camphora EO were examined, and P. aeruginosa and E. coli ATCC25922 showed the highest and lowest sensitivity to C. camphora EO, respectively. Tests of QS inhibitory activity revealed that C. camphora EO significantly decreased the production of violacein and biofilm biomass in C. violaceum, with the maximum inhibition rates of 63% and 77.64%, respectively, and inhibited the biofilm formation and swarming movement, independent of affecting the growth of C. violaceum. Addition of C. camphora EO also resulted in downregulation of the expression of the acyl-homoserine lactones (AHL) synthesis gene (cviI) and transcription regulator (cviR), and inhibited the expression of QS-regulated virulence genes, including vioA, vioB, vioC, vioD, vioE, lasA, lasB, pilE3, and hmsHNFR. Collectively, the prominent antibacterial activity and anti-QS activities clearly support that C. camphora EO acts as a potential antibacterial agent and QS inhibitor in the prevention of bacterial contamination.

Lateral Posterior Choroidal Collateral Anastomosis Predicts Recurrent Ipsilateral Hemorrhage in Adult Patients with Moyamoya Disease

BACKGROUND AND PURPOSE

Choroidal collateral anastomosis is associated with hemorrhage recurrence in patients with Moyamoya disease. However, the relationship between recurrent ipsilateral hemorrhage and choroidal collateral anastomosis subtypes (anterior choroidal artery anastomosis, lateral posterior choroidal artery anastomosis, and medial posterior choroidal artery anastomosis) is unclear. This study aimed to assess this potential association in adult patients with Moyamoya disease.

MATERIALS AND METHODS

Patients angiographically diagnosed with Moyamoya disease who underwent conservative treatment between January 2008 and December 2018 were included in this retrospective study. Two readers assessed the angiographic images to identify choroidal collateral anastomosis subtypes, and Cox proportional hazard regression models were used to estimate the risk of recurrent hemorrhage associated with each subtype.

RESULTS

Thirty-nine patients (mean age = 45.2 years) were included in this study. During 52.4 ± 37.0 months of follow-up, recurrent ipsilateral hemorrhage occurred in 48.7% (19/39) of patients. Patients with recurrent hemorrhage had a higher prevalence of choroidal collateral (94.8% versus 60.0%; P = .02) and lateral posterior choroidal artery (78.9% versus 25.0%; P < .01) anastomoses than those without recurrent hemorrhage. Lateral posterior choroidal artery anastomosis was associated with recurrent hemorrhage before (hazard ratio = 6.66; 95% CI, 2.18-20.39; P < .01) and after (hazard ratio = 5.78; 95% CI, 1.58-21.13; P < .01) adjustments were made for age, sex, and other confounding factors.

CONCLUSIONS

Choroidal collateral anastomosis is responsible for most cases of recurrent hemorrhage in adult patients with Moyamoya disease; lateral posterior choroidal artery anastomosis is a significant risk factor for these recurrent events.

Orientationally ordered states of a wormlike chain in spherical confinement

One of the basic characteristics of a linear dsDNA molecule is its persistence length, typically of order 50 nm. The DNA chain inflicts a large energy penalty if it is bent sharply at that length scale. Viruses of bacteria, known as bacteriophages, typically have a dimension of a few tens of nanometers. Yet, it is known that a bacteriophage actively packages viral DNA inside the capsid and ejects it afterwards. Here, adopting a commonly used polymer model known as the wormlike chain, we answer an idealized question: Placing a linear DNA molecule inside a spherical cavity, what ordered states can we derive from known tools in statistical physics? Solving the model in a rigorous field-theory framework, we report a universal phase diagram for four orientationally ordered and disordered states, in terms of two relevant physical parameters.

Conversion of human and mouse fibroblasts into lung-like epithelial cells

Cell lineage conversion of fibroblasts to specialized cell types through transdifferentiation may provide a fast and alternative cell source for regenerative medicine. Here we show that transient transduction of fibroblasts with the four reprogramming factors (Oct4, Sox2, Klf4, and c-Myc) in addition to the early lung transcription factor Nkx2-1 (also known as Ttf1), followed by directed differentiation of the cells, can convert mouse embryonic and human adult dermal fibroblasts into induced lung-like epithelial cells (iLEC). These iLEC differentiate into multiple lung cell types in air liquid interface cultures, repopulate decellularized rat lung scaffolds, and form lung epithelia composed of Ciliated, Goblet, Basal, and Club cells after transplantation into immune-compromised mice. As proof-of-concept, differentiated human iLEC harboring the Cystic Fibrosis mutation dF508 demonstrated pharmacological rescue of CFTR function using the combination of lumacaftor and ivacaftor. Overall, this is a promising alternative approach for generation of patient-specific lung-like progenitors to study lung function, disease and future regeneration strategies.

Increase in CFC-11 emissions from eastern China based on atmospheric observations

The recovery of the stratospheric ozone layer relies on the continued decline in the atmospheric concentrations of ozone-depleting gases such as chlorofluorocarbons¹. The atmospheric concentration of trichlorofluoromethane (CFC-11), the second-most abundant chlorofluorocarbon, has declined substantially since the mid-1990s². A recently reported slowdown in the decline of the atmospheric concentration of CFC-11 after 2012, however, suggests that global emissions have increased^3,4. A concurrent increase in CFC-11 emissions from eastern Asia contributes to the global emission increase, but the location and magnitude of this regional source are unknown³. Here, using high-frequency atmospheric observations from Gosan, South Korea, and Hateruma, Japan, together with global monitoring data and atmospheric chemical transport model simulations, we investigate regional CFC-11 emissions from eastern Asia. We show that emissions from eastern mainland China are 7.0 ± 3.0 (±1 standard deviation) gigagrams per year higher in 2014-2017 than in 2008-2012, and that the increase in emissions arises primarily around the northeastern provinces of Shandong and Hebei. This increase accounts for a substantial fraction (at least 40 to 60 per cent) of the global rise in CFC-11 emissions. We find no evidence for a significant increase in CFC-11 emissions from any other eastern Asian countries or other regions of the world where there are available data for the detection of regional emissions. The attribution of any remaining fraction of the global CFC-11 emission rise to other regions is limited by the sparsity of long-term measurements of sufficient frequency near potentially emissive regions. Several considerations suggest that the increase in CFC-11 emissions from eastern mainland China is likely to be the result of new production and use, which is inconsistent with the Montreal Protocol agreement to phase out global chlorofluorocarbon production by 2010.

Ethanol infiltration into the stapedio-vestibular joint reduces low-frequency vibration of the ossicular chain and round window membrane in the guinea pig

BACKGROUND

The synovial stapedio-vestibular joint (SVJ), which serves as a bridge between the stape and oval window, can be found in guinea pigs and most human adults. Unlike the fibrous SVJs in other animals, the contribution of the synovial SVJ to middle ear sound transmission remains unknown.

AIMS/OBJECTIVES

In this study, we investigate whether sclerosis of the synovial SVJ contributes to frequency-dependent vibration of the ossicular chain and round window membrane (RWM).

MATERIALS AND METHODS

A model of SVJ sclerosis model was established in the guinea pig using 75% ethanol. A laser Doppler vibrometer was then used to measure vibrations of the RWM and the long process of the incus (LPI) under pure tone sound stimulations of 0.25-16 kHz. The influence of SVJ sclerosis was analysed by comparing structural vibration displacement between the normal and sclerosis groups.

RESULTS

Both LPI and RWM vibrations significantly decreased at low frequencies after infiltration of ethanol, which caused SVJ sclerosis.

CONCLUSIONS

SVJ sclerosis reduces low-frequency vibration of the ossicular chain and RWM in the guinea pig, which indicates that the synovial SVJ is vital to low-frequency sound transmission in the middle ear.

SIGNIFICANCE

Providing useful data for further research regarding middle ear biomechanics.