Three-Dimensional Bimetallic Ammonium K-Eu Nitrate with a Rare (6,6)-Connected Ion Topology Exhibiting Structural Phase Transition and Photoluminescence Properties.

A K-Eu bimetallic ammonium metal-nitrate three-dimensional (3D) framework incorporating R-N-methyl-3-hydroxyquinuclidine, (RM3HQ)2KEu(NO3)6 (RM3HQ = R-N-methyl-3-hydroxyquinuclidine, 1), was characterized and reported. Distinguishing from the former hybrid rare-earth double perovskites, 1 adopts a mixed corner- and face-sharing K+/Eu3+-centered polyhedral connectivity to form a 3D inorganic framework, showing a rare (6, 6)-connected ion topology with a 66 framework. Notably, 1 exhibits clear phase transition, and the switchable thermodynamic behavior is confirmed by variable-temperature dielectric measurements and second-harmonic generation response. Moreover, 1 also shows photoluminescence properties. The activator Eu3+ plays a crucial role in this process, leading to a significant narrow emission at 592 nm with a photoluminescence quantum yield (PLQY) of 20.76%. The fluorescence lifetime (FLT) of 1 is 4.32 ms. This finding enriches the bimetallic hybrid system for potential electronic and/or luminescence applications.

Gas-Liquid Interface Route to Hybrid Copper Bromine Perovskite Single-Crystal Membrane with Dielectric Transitions and Ferromagnetic Exchanges.

Single-crystal membranes (SCMs) show great promise in the fields of sensors, light-emitting diodes, and photodetection. However, the growth of a large-area single-crystal membranes is challenging. We report a new organic-inorganic SCMs [HCMA]2CuBr4 (HCMA = cyclohexanemethylamine) crystallized at the gas-liquid interface. It also has low-temperature ferromagnetic order, high-temperature dielectric anomalies, and narrow band gap indirect semiconductor properties. Specifically, the reversible phase transition of the compound occurs at 350/341 K on cooling/heating and exhibits dielectric anomalies and stable switching performance near the phase transition temperature. The ferromagnetic exchange interaction in the inorganic octahedra and the organic layer enables ferromagnetic ordering at low-temperature 10 K. Finally, the single crystal exhibits an indirect semiconducting property with a narrow band gap of 0.99 eV. Such rich multichannel physical properties make it a potential application in photodetection, information storage and sensors.

ADAMTS7-Mediated Complement Factor H Degradation Potentiates Complement Activation to Contributing to Renal Injuries.

BACKGROUND: The dysfunction of complement factor H (CFH), the main soluble complement negative regulator, potentiates various complement-induced renal injuries. However, insights into the underlying mechanism of CFH dysfunction remain limited. In this study, we investigated whether extracellular protease-mediated degradation accounts for CFH dysfunction in complement-mediated renal injuries. METHODS: An unbiased interactome of lupus mice kidneys identified CFH-binding protease. In vitro cleavage assay clarified CFH degradation. Pristane-induced SLE or renal ischemia-reperfusion (I/R) injury models were used in wild-type and ADAMTS7-/- mice. RESULTS: We identified the metalloprotease ADAMTS7 as a CFH-binding protein in lupus kidneys. Moreover, the upregulation of ADAMTS7 correlated with CFH reduction in both lupus mice and patients. Mechanistically, ADAMTS7 is directly bound to CFH complement control protein (CCP) 1-4 domain and degraded CCP 1-7 domain through multiple cleavages. In mice with lupus nephritis or renal I/R injury, ADAMTS7 deficiency alleviated complement activation and related renal pathologies, but without affecting complement-mediated bactericidal activity. Adeno-associated virus-mediated CFH silencing compromised these protective effects of ADAMTS7 knockout against complement-mediated renal injuries in vivo. CONCLUSION: ADAMTS7-mediated CFH degradation potentiates complement activation and related renal injuries. ADAMTS7 would be a promising anticomplement therapeutic target that does not increase bacterial infection risk.

The Mechanism of Tigecycline Resistance in Acinetobacter baumannii under Sub-Minimal Inhibitory Concentrations of Tigecycline.

The presence of sub-minimal inhibitory concentration (sub-MIC) antibiotics in our environment is widespread, and their ability to induce antibiotic resistance is inevitable. Acinetobacter baumannii, a pathogen known for its strong ability to acquire antibiotic resistance, has recently shown clinical resistance to the last-line antibiotic tigecycline. To unravel the complex mechanism of A. baumannii drug resistance, we subjected tigecycline-susceptible, -intermediate, and -mildly-resistant strains to successive increases in sub-MIC tigecycline and ultimately obtained tigecycline-resistant strains. The proteome of both key intermediate and final strains during the selection process was analyzed using nanoLC-MS/MS. Among the more than 2600 proteins detected in all strains, we found that RND efflux pump AdeABC was associated with the adaptability of A. baumannii to tigecycline under sub-MIC pressure. qRT-PCR analysis also revealed higher expression of AdeAB in strains that can quickly acquire tigecycline resistance compared with strains that displayed lower adaptability. To validate our findings, we added an efflux pump inhibitor, carbonyl cyanide m-chlorophenyl hydrazine (CCCP), to the medium and observed its ability to inhibit tigecycline resistance in A. baumannii strains with quick adaptability. This study contributes to a better understanding of the mechanisms underlying tigecycline resistance in A. baumannii under sub-MIC pressure.

Anti-phospholipid autoantibodies in human diseases.

Anti-phospholipid autoantibodies are a group of antibodies that can specifically bind to anionic phospholipids and phospholipid protein complexes. Recent studies have reported elevated serum anti-phospholipid autoantibody levels in patients with antiphospholipid syndrome, systemic lupus erythematosus, rheumatoid arthritis, metabolic disorders, malaria, SARS-CoV-2 infection, obstetric diseases and cardiovascular diseases. However, the underlying mechanisms of anti-phospholipid autoantibodies in disease pathogenesis remain largely unclear. Emerging evidence indicate that anti-phospholipid autoantibodies modulate NETs formation, monocyte activation, blockade of apoptotic cell phagocytosis in macrophages, complement activation, dendritic cell activation and vascular endothelial cell activation. Herein, we provide an update on recent advances in elucidating the effector mechanisms of anti-phospholipid autoantibodies in the pathogenesis of various diseases, which may facilitate the development of potential therapeutic targets for the treatment of anti-phospholipid autoantibody-related disorders.

Long-term variations and potency of neutralizing antibodies against Omicron subvariants after CoronaVac-inactivated booster: A 7-month follow-up study.

The long-term protective efficacy of neutralizing antibodies (Nabs) against Omicron subvariants after inactivated booster vaccines remains elusive. During the follow-up study, 54 healthy volunteers aged 20-31 years received inactivated CoronaVac booster vaccinations and were monitored for 221 days. The dynamic efficacy and durability of Nab against Omicron subvariants BA.1, BA.2, BA.2.12.2, and BA4/5 were assessed using a pseudotyped virus neutralization assay at up to nine time points post immunization. The antibody response against Omicron subvariants was substantially weaker than D614G, with BA.4/5 being the least responsive. The geometric mean titer (GMT) of Nab against Omicron subvariants BA.1, BA.2, BA.2.12.1, and BA.4/5 was 2.2-, 1.7-, 1.8-, and 2.2-fold lower than that against D614G (ps < 0.0001). The gap in Nab response between Omicron subvariants was pronounced during the 2 weeks-2 months following booster vaccination (ps < 0.05). Seven months post booster, the antibody potency against D614G was maintained at 100% (50% for Nab titers ≥ 100 50% inhibitory dilution [EC50 ]), whereas at 77.3% for BA.1, 90.9% for BA.2, 86.4% for BA.2.12.1, and 86.4% for BA.4/5 (almost 20% for Nab titers ≥ 100 EC50 ). Despite the inevitable immune escape, Omicron subvariants maintained sustained and measurable antibody potency post-booster vaccination during long-term monitoring, which could help optimize immunization strategies.

The Mechanism of Tigecycline Resistance in Acinetobacter baumannii Revealed by Proteomic and Genomic Analysis.

The mechanism of tigecycline resistance in A. baumannii remains largely unclear. In this study, we selected a tigecycline-resistant and a tigecycline-susceptible strain from a tigecycline-susceptible and a resistant strain, respectively. Proteomic and genomic analyses were performed to elucidate the variations associated with tigecycline resistance. Our study showed proteins associated with efflux pump, biofilm formation, iron acquisition, stress response, and metabolic ability are upregulated in tigecycline resistant strains, and efflux pump should be the key mechanism for tigecycline resistance. By genomic analysis, we found several changes in the genome that can explain the increased level of efflux pump, including the loss of the global negative regulator hns in the plasmid and the disruption of the hns gene and acrR gene on the chromosome by the insertion of IS5. Collectively, we not only revealed the phenomenon that the efflux pump is mainly responsible for tigecycline resistance, but also highlighted the mechanism at the genomic level, which will help in understanding the resistance mechanism in detail and provide clues for the treatment of clinical multiple drug-resistant A. baumannii.

The type VI secretion system in Acinetobacter baumannii clinical isolates and its roles in antimicrobial resistance acquisition.

Acinetobacter baumannii is a successful pathogen that can acquire various antibiotic resistance in a short time. However, little is known about how it can evolve from an antibiotic sensitive to a resistant phenotype. In this study, we investigated the roles of the type VI secretion system (T6SS) in the acquisition of antibiotic resistance of A. baumannii. T6SS gene cluster was found to be present in 51 of 77 A. baumannii clinical isolates, of which, it was found in 62% (8/13) of the multiple drug resistant (MDR) isolates, 90% (36/40) of the extensively drug-resistant (XDR) isolates and 26% (6/23) of the antibiotic sensitive isolates. There is a close relationship between the antimicrobial resistance and the presence of T6SS. Besides, T6SS + isolates showed lower biofilm formation activity and higher survival ability in the presence of normal human serum than T6SS- isolates. A. baumannii A152 with complete T6SS can outcompete E.coli effectively and can acquire the antibiotic resistance plasmids released by E.coli. In contrast, the T6SS core gene mutant A152Δhcp showed significantly decreased ability to acquire antimicrobial resistance plasmids from the prey bacteria. These results suggest that T6SS mediated bacterial competition plays important roles in the antimicrobial resistance of A. baumannii, which points out a new direction for us to study the antimicrobial resistance of A. baumannii.

Comparative genomics analysis of Acinetobacter baumannii multi-drug resistant and drug sensitive strains in China.

The incidence of multidrug-resistant Acinetobacter baumannii has posed a major challenge for clinical treatment. There is still a significant gap in understanding the mechanism causing multi-drug resistance (MDR). In this study, the genomes of 10 drug sensitive and 10 multi-drug resistant A.baumannii strains isolated from a hospital in China were sequenced and compared. The antibiotic resistance genes, virulence factors were determined and CRIPSR-Cas system along with prophages were detected. The results showed that MDR strains are significantly different from the drug sensitive strains in the CARD entries, patterns of sequences matching up to plasmids, VFDB entries and CRISPR-Cas system. MDR strains contain unique CARD items related to antibiotic resistance which are absent in sensitive strains. Furthermore, sequences from genomes of MDR strains can match up with plasmids from more diversified bacteria genera compared to drug sensitive strains. MDR strains also contain a lower level of CRISPR genes and larger amount of prophages, along with higher levels of spacer sequences. These findings provide new experimental evidences for the study of the antibiotic resistance mechanism of A. baumannii.

Tumour necrosis factor inhibitor combined with intravenous immunoglobulin and heparin for treatment of recurrent spontaneous abortion: A two-centre, retrospective, cohort study.

WHAT IS KNOWN AND OBJECTIVE: Immune disorder is a key trigger of recurrent spontaneous abortion (RSA); meanwhile, tumour necrosis factor inhibitor (TNFi) is a fundamental therapeutic for multiple immune and inflammatory diseases. Hence, this real-world study aimed to explore the efficacy and safety of TNFi combined with intravenous immunoglobin (IVIG) and heparin therapy in RSA patients. METHODS: A total of 105 RSA patients who received TNFi+IVIG+Heparin (enoxaparin) (n = 48) or IVIG+Heparin (enoxaparin) (n = 57) were retrospectively included in this two-centre cohort study. RESULTS AND DISCUSSION: The live birth rate of RSA patients in the TNFi+IVIG+heparin group was 72.9% (95% confidence interval [CI]: 69.6%-85.9%). Besides, the live birth rate in the IVIG+heparin group was 52.6% (95% CI: 42.8%-62.4%). By comparison, the live birth rate was higher in the TNFi+IVIG+heparin group compared to the IVIG+heparin group (p = 0.033). After adjustment by the multivariate logistic regression model using the enter method, TNFi+IVIG+Heparin was also superior to IVIG+Heparin regarding increased live birth rate (odds ratio [OR] = 2.941, p = 0.015). Moreover, TNFi+IVIG+Heparin (vs. IVIG+Heparin) also served as an independent factor for increased live birth rate (OR = 2.423, p = 0.035) by the forward stepwise method in the multivariate analysis. Gestational weeks at delivery (38.3 ± 1.3 vs. 37.7 ± 2.0 weeks, p = 0.155), newborn weight (3123.9 ± 332.1 vs. 3056.6 ± 287.4 g, p = 0.390), Apgar score of newborns (9.8 ± 0.5 vs. 9.7 ± 0.7, p = 0.271) were of no difference between TNFi+IVIG+Heparin and IVIG+Heparin groups. In terms of safety profile, the adverse events were of no difference between the TNFi+IVIG+Heparin and the IVIG+Heparin groups (all p > 0.05), either. WHAT IS NEW AND CONCLUSION: TNFi combined with IVIG and heparin therapy improves the live birth rate but does not elevate the adverse events compared to IVIG and heparin therapy in RSA patients.

Salmonella Regulator STM0347 Mediates Flagellar Phase Variation via Hin Invertase.

Salmonella enterica is one of the most important food-borne pathogens, whose motility and virulence are highly related to flagella. Flagella alternatively express two kinds of surface antigen flagellin, FliC and FljB, in a phenomenon known as flagellar phase variation. The molecular mechanisms by which the switching orientation of the Hin-composed DNA segment mediates the expression of the fljBA promoter have been thoroughly illustrated. However, the precise regulators that control DNA strand exchange are barely understood. In this study, we found that a putative response regulator, STM0347, contributed to the phase variation of flagellin in S. Typhimurium. With quantitative proteomics and secretome profiling, a lack of STM0347 was confirmed to induce the transformation of flagellin from FliC to FljB. Real-time PCR and in vitro incubation of SMT0347 with the hin DNA segment suggested that STM0347 disturbed Hin-catalyzed DNA reversion via hin degradation, and the overexpression of Hin was sufficient to elicit flagellin variation. Subsequently, the Δstm0347 strain was outcompeted by its parental strain in HeLa cell invasion. Collectively, our results reveal the crucial role of STM0347 in Salmonella virulence and flagellar phase variation and highlight the complexity of the regulatory network of Hin-modulated flagellum phase variation in Salmonella.

Complete genome sequence and virulence characterization of a neonatal meningitis Escherichia coli isolate.

Neonatal bacterial meningitis is a life-threatening disease in newborns, and neonatal meningitis Escherichia coli (NMEC) is the second most frequent bacteria causing this disease worldwide. In order to further understand the characteristics of this pathogen, an E. coli isolate W224 N from newborns with meningitis was sequenced for detailed genetic characterization and the virulence was tested by a series of phenotypic experiments. W224 N has a circular chromosome and three plasmids. It belongs to ST95 and the serotype is O18:H7. Comparative genomic analysis showed that W224 N was closely related to E. coli neonatal meningitis isolates RS218 and NMEC O18. There are 11 genomic islands in W224 N and most of the GIs are specific to W224 N. W224 N has most of the virulence factors other neonatal meningitis isolates have. The virulence genes located both on the genome and plasmid. At the same time, we found a virulence factor cdiA only present in W224 N but absent in the other five genomes analyzed. In vitro experiment showed that W224 N has strong serum resistance ability, low biofilm formation ability and high flagellar motility. It also has a very strong toxicity to mice and amoeba. The whole genome as well as in vitro and in vivo experiments showed that W224 N is a high virulent strain. The results can help us better learn about the pathogenicity of neonatal meningitis E. coli.

Validation of new classification criteria of rheumatoid arthritis in an international multicentre study.

OBJECTIVES: Early identification of patients with rheumatoid arthritis (RA) is essential to allow prompt therapy. In this study, we aimed to evaluate the performance of the newly proposed ERA criteria, compared to the 1987 ACR and 2010 ACR/EULAR criteria in an international multicentre study. METHODS: A total of 606 patients with disease duration ≤2 years and age ≥16 years who were diagnosed as RA or non-RA were enrolled from China, Sweden and India. The clinical and laboratory parameters were recorded. We compared the sensitivity, specificity, predictive value, likelihood ratio (LR), and the area under the ROC curve (AUC) of three criteria in these cohorts. Concordance between the three criteria was calculated with the Kappa coefficient. RESULTS: Three hundred and twelve RA and 294 non-RA patients were included. The Early Rheumatoid Arthritis (ERA) criteria had significantly higher specificity compared to the 2010 ACR/ EULAR criteria (83.7% vs. 78.2%, p=0.02) and sensitivity were similar (79.2% vs. 78.5%, p=0.883). In comparison with the 1987 ACR criteria, the ERA criteria had higher sensitivity (79.2% vs. 54.5%, p<0.001) but lower specificity (83.7% vs. 89.1%, p<0.001), and the AUC of the ERA criteria (0.878) was comparable to the 2010 ACR/EULAR criteria (0.849) and higher than the 1987 ACR criteria (0.791, p<0.0001). Patients from the three countries, seronegative and very early arthritis cohorts yielded consistent results. CONCLUSIONS: The ERA criteria demonstrate a better performance across ethnics in early RA diagnosis, and is more feasible in daily practice.

Correlation of Polymorphisms of Natural Resistance-Associated Macrophage Protein 1 (NRAMP1) Gene and Smoking with the Risk of Rheumatoid Arthritis in Chinese Han People.

BACKGROUND In this study we report on the possible connection between single nucleotide polymorphisms (SNPs) in natural resistance-associated macrophage protein 1 (NRAMP1) gene and the risk of rheumatoid arthritis (RA) in the Chinese Han population. MATERIAL AND METHODS A total of 248 participants consisting of 116 RA cases and 132 healthy individuals were recruited for the current study. Genotyping for NRAMP1 gene polymorphisms was implemented using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The chi-square test was used to detect discrepancies in genotype and allele frequencies between the RA case group and the control group. Odds ratios (ORs) with 95% confidence intervals (CIs) was used to evaluate relative risk of RA. The results were adjusted by logistic regression analysis. RESULTS The TT genotype and T allele in rs17221959 showed dramatically different distribution between RA cases and healthy controls. After adjustment, TT genotype (OR=0.338, 95%CI=0.278-1.214, P=0.028) and T allele (OR=0.608, 95%CI=0.298-0.956, P=0.005) showed close association with reduced risk of RA. For rs1059823, no obvious diversity was uncovered in either genotype or allele distribution between the 2 groups. Interaction analysis showed that smoking decreased the protective function of TT in rs17221959. CONCLUSIONS This study suggested that the TT genotype and T allele in rs17221959 decreased RA risk. Smoking could decrease the protective effect of TT.

Effects of anti-Helicobacter pylori concomitant therapy and probiotic supplementation on the throat and gut microbiota in humans.

The microbiota within humans maintains homeostasis and plays important roles in human health. However, some situations such as the use of antibiotics may disrupt the microbiota balance and result in a series of adverse effects. This study aimed to investigate the effects of a commonly used anti-Helicobacter pylori concomitant therapy on the composition of the gut and throat microbiota and any antibiotic resistance that may develop. In addition to the standard regimen, two different supplementary probiotic regimens that both used Saccharomyces boulardii were included. Microbiological culture-based techniques were used to analyse the microbiota composition and antibiotic resistance. Our results showed marked quantitative and qualitative alterations in both the gut and throat microbiota after treatment with not only the standard concomitant therapy but also with either supplementary probiotic regimen. Nevertheless, most of the changes in the gut microbiota (except for yeast and Bacteroides spp. counts) reverted by Day 71, whereas the alterations in the throat microbiota appeared to persist. Patients treated with the eradication therapy in the absence of probiotic supplementation experienced the most pronounced disturbances in the throat microbiota, whereas changes in the throat microbiota appeared to stabilize in the groups that received probiotic supplementation. We also detected higher antibiotic resistance rates for Enterobacteriaceae, Enterococcus spp. and Bacteroides spp. after treatment with the eradication therapy. Co-administration of probiotics is likely to be more effective than post-antibiotic supplementation, and although some beneficial effects were observed, the probiotic combination did not exert significant effects on the unbalanced commensal gut and throat microbiota composition.

Mix-breeding with HEV-infected swine induced inapparent HEV infection in SPF rabbits.

Studies have shown that swine HEV (sHEV) and rabbit HEV (rHEV) can experimentally infect rabbits and swine, respectively. However, no published data have documented isolating sHEV strains from rabbits in natural environment so far. To clarify the possibility of natural cross-species transmission of sHEV to rabbits, the pigs with HEV infection were farmed along with SPF rabbits in the same enclosed space. Five of 10 rabbits had seroconversion for anti-HEV antibody from the third week after mix-breeding. However, HEV RNA remained undetectable in feces, serum, liver and bile of the ten rabbits; and no obvious elevation of ALT was observed. The results possibly suggested that sHEV might lead to an inapparent infection of SPF rabbits by fecal-oral route.

Correlation of Axial Spondyloarthritis with Anxiety and Depression.

BACKGROUND This study compared anxiety and depression in patients with nonradiographic axial spondyloarthritis (nr-axSpA) versus patients with ankylosing spondylitis (AS), and examined the relationship between clinical characteristics and psychological status. MATERIAL AND METHODS Patients diagnosed with axial spondyloarthritis (axSpA) were recruited for the study. Disease status was evaluated by the bath ankylosing spondylitis disease activity index (BASDAI), the bath ankylosing spondylitis functional index, visual analog scale, and the level of inflammatory markers. Psychological status was evaluated by the self-rating anxiety scale (SAS) and the self-rating depression scale (SDS). RESULTS Sixty patients with axSpA were enrolled in the study, including 40 patients with AS and 20 patients with nr-axSpA. Patients with AS and patients with nr-axSpA had similar disease status and psychological status. Anxiety was significantly associated with disease status and SDS score (P<0.05 for all), whereas BASDAI (odds ratio [OR]=0.28, 95% CI=0.08-0.97, P=0.045) and SDS (OR=0.90, 95% CI=0.82-0.98, P=0.014) protected against anxiety. Depression was obviously correlated with smoking history, disease status, and SAS score (P<0.05 for all). Smoking history (OR=10.18, 95% CI=1.23-84.23, P=0.031) and SAS score (OR=0.85, 95% CI=0.75-0.97, P=0.014) were negatively correlated with risk of depression. CONCLUSIONS Patients with AS and patients with nr-axSpA had similar psychological status in terms of anxiety and depression. Disease status and smoking were significantly correlated with psychological status. Patients with higher SAS scores were more likely to have depression. The results of this study may be helpful to clinically guide psychological interventions for patients with axSpA.

[Distribution in different Salmonella serovars and integration sites of Salmonella paratyphi C phage SPC-P1].

OBJECTIVE: To determine the prevalence of Salmonella paratyphi C phage (SPC-P1) in different Salmonella serovars and to identify the integration sites in host genome. METHODS: Based on the complete genome of SPC-P1 in S. paratyphi C RKS4594, 6 pairs of primers were designed and used to amplify the fragments of SPC-P1 in 11 S. typhi, 11 S. paratyphi A, 12 S. paratyphi B and 23 S. paratyphi C strains. At the same time, 100 complete genomes of Salmonella including 20 serovars available in National Center for Biotechnology Information (NCBI) database were downloaded and aligned by Mauve 2.3.1 to determine the prevalence of SPC-P1 in these serovars. Primers were designed according to the integration sites of SPC-P1 in the genome of RKS4594, and used to amplify ten strains having SPC-P1 in the genome. The PCR products were sequenced to investigate the integration sites of SPC-P1. RESULTS: SPC-P1 was widely distributed in S.paratyphi C genome. In the study, 14 strains had all 6 fragments and 2 strains had 3-5 fragments. All the amplified fragments showed expected sizes. In contrast, in the genomes of S. typhi, S. paratyphi A and S. paratyphi B, no or only 1-2 fragments could be amplified, and the sizes were smaller than expected. The results from Mauve showed that only in the genome of S.choleraesuis, which was a close relative of S. paratyphi C, there existed an almost complete genome of SPC-P1. The insertion site of SPC-P1 in all the ten S. paratyphi C strains tested was between pgtE and yfdC genes. CONCLUSION: SPC-P1 is a unique virulence factor of S. paratyphi C. It may play roles in the host range and pathogenicity of S.paratyphi C.

Classification criteria of early rheumatoid arthritis and validation of its performance in a multi-centre cohort.

OBJECTIVES: To develop classification criteria for early rheumatoid arthritis (ERA) based on a large cohort of early inflammatory arthritis patients and to evaluate the performance of these criteria. METHODS: The study population comprised a cohort of early inflammatory arthritis patients with symptom duration less than one year. Classification criteria of ERA were developed by incorporating the most sensitive or specific variables. Performance of the ERA criteria, 1987 ACR and 2010 ACR/EULAR criteria were evaluated. RESULTS: A total of 803 patients were enrolled in this study. By the end of the one year follow-up, 514 patients were diagnosed with RA, 251 with other rheumatic diseases, and 38 patients with undifferentiated arthritis. The ERA criteria are as follows: 1) morning stiffness ≥30 minutes; 2) arthritis of 3 or more joint areas; 3) arthritis of hand joints; 4) positive RF; 5) positive anti-CCP antibody. Rheumatoid arthritis is defined by the presence of 3 or more of the criteria. The sensitivity (84.4%) of the ERA classification criteria was much higher than the 1987 ACR criteria (58.0%). In a validation cohort of early inflammatory arthritis patients, the area under the ROC curves (AUC) showed a better performance for the ERA criteria (0.906, 95%CI 0.866 to 0.945) than the 1987 ACR criteria (0.786, 95%CI 0.725 to 0.848) and the 2010 ACR/EULAR criteria (0.745, 95%CI 0.677 to 0.814). CONCLUSIONS: A set of ERA classification criteria has been developed with good performance for early RA. It is applicable in clinical practice and research.