First Observation of a Doubly Charged Tetraquark and Its Neutral Partner

A combined amplitude analysis is performed for the decays B^{0}→D[over ¯]^{0}D_{s}^{+}π^{-} and B^{+}→D^{-}D_{s}^{+}π^{+}, which are related by isospin symmetry. The analysis is based on data collected by the LHCb detector in proton-proton collisions at center-of-mass energies of 7, 8, and 13 TeV. The full data sample corresponds to an integrated luminosity of 9  fb^{-1}. Two new resonant states with masses of 2.908±0.011±0.020  GeV and widths of 0.136±0.023±0.013  GeV are observed, which decay to D_{s}^{+}π^{+} and D_{s}^{+}π^{-} respectively. The former state indicates the first observation of a doubly charged open-charm tetraquark state with minimal quark content [cs[over ¯]ud[over ¯]], and the latter state is a neutral tetraquark composed of [cs[over ¯]u[over ¯]d] quarks. Both states are found to have spin-parity of 0^{+}, and their resonant parameters are consistent with each other, which suggests that they belong to an isospin triplet.

Search for Rare Decays of D^{0} Mesons into Two Muons

A search for the very rare D^{0}→μ^{+}μ^{-} decay is performed using data collected by the LHCb experiment in proton-proton collisions at sqrt[s]=7, 8, and 13 TeV, corresponding to an integrated luminosity of 9  fb^{-1}. The search is optimized for D^{0} mesons from D^{*+}→D^{0}π^{+} decays but is also sensitive to D^{0} mesons from other sources. No evidence for an excess of events over the expected background is observed. An upper limit on the branching fraction of this decay is set at B(D^{0}→μ^{+}μ^{-})<3.1×10^{-9} at a 90% C.L. This represents the world's most stringent limit, constraining models of physics beyond the standard model.

Observation of a J/ψΛ Resonance Consistent with a Strange Pentaquark Candidate in B^{-}→J/ψΛp[over ¯] Decays

An amplitude analysis of B^{-}→J/ψΛp[over ¯] decays is performed using 4400 signal candidates selected on a data sample of pp collisions recorded at center-of-mass energies of 7, 8, and 13 TeV with the LHCb detector, corresponding to an integrated luminosity of 9  fb^{-1}. A narrow resonance in the J/ψΛ system, consistent with a pentaquark candidate with strangeness, is observed with high significance. The mass and the width of this new state are measured to be 4338.2±0.7±0.4  MeV and 7.0±1.2±1.3  MeV, where the first uncertainty is statistical and the second systematic. The spin is determined to be 1/2 and negative parity is preferred. Because of the small Q-value of the reaction, the most precise single measurement of the B^{-} mass to date, 5279.44±0.05±0.07  MeV, is obtained.

Neurological complications of COVID-19

Corona Virus Disease 2019 (COVID-19) has caused several pandemic peaks worldwide due to its high variability and infectiousness, and COVID-19 has become a long-standing global public health problem. There is growing evidence that severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) frequently causes multi-organ injuries and more severe neurological manifestations. Therefore, increased awareness of possible neurological complications is beneficial in preventing and mitigating the impact of long-term sequelae and improving the prognostic outcome of critically ill patients with COVID-19. Here, we review the main pathways of SARS-CoV-2 neuroinvasion and the potential mechanisms causing neurological damage. We also discuss in detail neurological complications, aiming to provide cutting-edge basis for subsequent related basic research and clinical studies of diagnosis and treatment.

Correlation study between apparent diffusion coefficients and the prognostic factors in breast cancer

AIM

To analyse the correlation between apparent diffusion coefficients (ADC) derived from intratumoural and peritumoural regions with prognostic factors and immune-inflammatory markers in breast cancer (BC).

MATERIALS AND METHODS

In this retrospective study, 89 patients (age range, 28-66 years; median, 45 years) with a diagnosis of invasive BC who underwent routine blood tests and multiparametric magnetic resonance imaging (MRI) were enrolled. The study cohort was stratified according to tumour maximum cross-section ≥20 mm, lymph node metastasis (LNM), time-signal intensity curve (TIC) type, and receptor status. Minimum, maximum, mean, and heterogeneity values of tumour ADC (ADC_tmin, ADC_tmax, ADC_tmean, and ADC_heter), maximum values of peritumoural ADC (ADC_pmax), and the ratio of peritumoural-tumour ADC (ADC_ratio) were obtained on the ADC maps. Linear regression analyses were performed to investigate the correlation between immune-inflammatory markers, prognostic factors and ADC values.

RESULTS

HER-2 was positively associated with ADC_tmax, ADC_tmean, and ADC_pmax values (β = 0.306, p=0.004; β = 0.283, p=0.007; β = 0.262, p=0.007, respectively), while platelet-to-lymphocyte ratio (PLR) was positively associated with ADC_pmax and ADC_ratio values (β = 0.227, p=0.020; β = 0.231, p=0.020, respectively). Among ADC parameters, ADC_pmax showed the highest predictive values for evaluating the presence of LNM (AUC, 0.751; sensitivity, 70.4%; specificity, 77.1%).

CONCLUSION

The ADC_pmax value could provide additional assistance in predicting prognostic factors of BC.

Effects of ruminal protozoa on methane emissions in ruminants-A meta-analysis

The effects of different ruminal protozoa (RP) on CH₄ emissions from ruminants were evaluated in a meta-analysis, using 64 publications reporting data from 79 in vivo experiments. Experiments included in the database reported CH₄ emissions (g/d) and total RP (TRP, log₁₀ cells/mL) from the same group of animals. The relationship between CH₄ emissions and RP (TRP, entodiniomorphids, and isotrichids), and TRP-, entodiniomorphid-, and isotrichid-based CH₄ emission prediction models, were evaluated as mixed models with experiment as a random effect and weighted by the reciprocal of the standard error of the mean and centered around one. Positive associations existed between TRP and isotrichids with CH₄ emissions but not between entodiniomorphids and CH₄ emissions. A reduction in CH₄ emissions was observed, averaging 7.96 and 4.25 g/d, per log unit reduction in TRP and isotrichid concentrations, respectively. Total RP and isotrichids were important variables in predicting CH₄ emissions from ruminants. Isotrichid CH₄ prediction model was more robust than the TRP, evidenciated by lower predicted sigma hat study (%), and error (%), and with higher concordance correlation coefficient. Both TRP and isotrichid models can accurately predict CH₄ emissions across different ruminant types, as shown by the low square root of the mean square prediction error, with 6.59 and 4.08% of the mean of root of the mean square prediction error in the TRP and isotrichid models, respectively. Our results confirm that isotrichids are more important than entodiniomorphids in methanogenesis. Distinguishing these 2 populations yielded a more robust CH₄ prediction model than combining them as total protozoa.

Feed efficiency of lactating Holstein cows is repeatable within diet but less reproducible when changing dietary starch and forage concentrations

Improving feed efficiency has become an important target for dairy farmers to produce more milk with fewer feed resources. With decreasing availability of arable land to produce feeds that are edible for human consumption, it will be important to increase the proportion of feeds in the diets for dairy cattle that are less edible for human consumption. The current research analyzed the ability of lactating dairy cows to maintain their feed efficiency when switching between a high starch diet (HS diet: 27% starch, 29% NDF, 47.1% forages on a DM basis) and a low starch diet (LS diet: 13% starch, 37% NDF, 66.4% forages on a DM basis). Sixty-two lactating Holstein cows (137 ± 23 days in milk (DIM) at the start of experiment), of which 29 were primiparous cows, were utilized in a crossover design with two 70-d experimental periods, including a 14-d adaption period for each. Feed efficiency was estimated as the individual deviation from the population average intercept in a mixed model predicting DM intake (DMI) with net energy in milk, maintenance and BW gain and loss. Repeatability was estimated within each diet by comparing feed efficiency estimated over the first 28-day period and the second 28-day period within each diet, using Pearson's and intraclass correlations, and the estimation of error of repeatability. Similarly, reproducibility was estimated by comparing the second 28-day period of one diet with the first 28-day period of the other diet. Feed efficiency was less reproducible across diets than repeatable within the same diet. This was shown by lower intraclass correlations (0.399) across diets compared to that in the HS diet (0.587) and LS diet (0.806), as well as a lower Pearson's correlation coefficient (0.418) across diets compared to that in the HS diet (0.630) and LS diet (0.809). In addition, the estimation of error of repeatability was higher (0.830 kg DM/d) across diets compared to that in the HS diet (0.761 kg DM/d) and LS diet (0.504 kg DM/d). This means that the feed efficiency of dairy cows is more likely to change after a diet change than over subsequent lactation stages. Other determinants, such as digestive processes, need to be further investigated to determine its effects on estimating feed efficiency.

Insights into acylation mechanisms: co-expression of serine carboxypeptidase-like acyltransferases and their non-catalytic companion paralogs

Serine carboxypeptidase-like acyltransferases (SCPL-ATs) play a vital role in the diversification of plant metabolites. Galloylated flavan-3-ols highly accumulate in tea (Camellia sinensis), grape (Vitis vinifera), and persimmon (Diospyros kaki). To date, the biosynthetic mechanism of these compounds remains unknown. Herein, we report that two SCPL-AT paralogs are involved in galloylation of flavan-3-ols: CsSCPL4, which contains the conserved catalytic triad S-D-H, and CsSCPL5, which has the alternative triad T-D-Y. Integrated data from transgenic plants, recombinant enzymes, and gene mutations showed that CsSCPL4 is a catalytic acyltransferase, while CsSCPL5 is a non-catalytic companion paralog (NCCP). Co-expression of CsSCPL4 and CsSCPL5 is likely responsible for the galloylation. Furthermore, pull-down and co-immunoprecipitation assays showed that CsSCPL4 and CsSCPL5 interact, increasing protein stability and promoting post-translational processing. Moreover, phylogenetic analyses revealed that their homologs co-exist in galloylated flavan-3-ol- or hydrolyzable tannin-rich plant species. Enzymatic assays further revealed the necessity of co-expression of those homologs for acyltransferase activity. Evolution analysis revealed that the mutations of the CsSCPL5 catalytic residues may have taken place about 10 million years ago. These findings show that the co-expression of SCPL-ATs and their NCCPs contributes to the acylation of flavan-3-ols in the plant kingdom.

POS0274 PREDICTION OF VASCULAR COMPLICATIONS IN TAKAYASU ARTERITIS BY MACHINE LEARNING: A PROOF-OF-CONCEPT STUDY BASED ON A PROSPECTIVE COHORT

Background

Vascular complications are common poor prognosis in Takayasu arteritis (TAK). A reliable prediction model for this outcome has not been performed using machine learning (ML) due to the lack of a dataset with sufficient sample size.

Objectives

We aimed to develop ML models for prediction of vascular complications in TAK based on the prospective data of the largest sample in China from the East China Takayasu Arteritis (ECTA) cohort.

Methods

Data were collected from the ECTA cohort in which patients were enrolled from January 2009 to August 2020 and followed till February 2021 (n = 517). Predictor variables included 53 baseline features and outcome of interest was incident vascular complications. Data were randomly split into a training (85%) and test (15%) set. Logistic regression (LR), support vector machine, random forest (RF), k-nearest neighbors, XGBoost (XGB), and light gradient boosting machine models were trained using five-fold cross validation, and evaluated on the test set for recall, specificity, precision and area under ROC (AU-ROC) and precision-recall curves (AU-PRC). Permutation score was applied to assess feature importance to the outcome.

Results

Over a median follow-up of 30 (15–44) months, incident vascular complications were observed in 29.0% (150/517) patients. The RF model demonstrated the best overall predictive performance (AU-ROC = 0.84, AU-PRC = 0.63). Both the RF and LR models had the highest specificity (0.98), and the XGB model had the highest recall (0.87). Progressive clinical course was an important feature significantly associated with the outcome for all models.

Conclusion

It demonstrated the feasibility of developing ML models for prediction of vascular complications in TAK. The XGB model could help for early identification of high-risk patients, and RF and LR models could further confirm.

Figure 1.

Disclosure of Interests

None declared

POS0812 CAROTID INTIMA-MEDIA THICKNESS/DIAMETER RATIO AND PEAK SYSTOLIC VELOCITY AS RISK FACTORS FOR NEUROLOGICAL SEVERE ISCHEMIC EVENTS IN TAKAYASU’S ARTERITIS

Background

Takayasu’s arteritis (TAK) is an idiopathic systemic vasculitis characterized by the involvement of the aorta and its major branches [1]. The supra-aortic arteries are often involved in TAK, with the reported prevalence ranging from 40% to 84% [2-3]. Importantly, patients with supra-aortic involvement carry a higher risk of neurological severe ischemic events (SIE) [4-5]. The common carotid artery (CCA) is the most affected artery and is more closely associated with neurologic symptoms than other supra-aortic arteries [6]. Ultrasonography (US) has been regarded as the most popular, user-friendly, and repeatable tool for the diagnosis and follow-up of CCA injuries.

Objectives

Our aim was to characterize TAK with supra-aortic involvement and determine the associations between clinical features, carotid US parameters, and neurological SIE.

Methods

Patients with supra-aortic involvement including brachiocephalic trunk, bilateral common carotid artery and internal carotid artery, and bilateral subclavian and vertebral artery and baseline carotid US examination were enrolled. Bilateral carotid diameter, intima-media thickness (IMT), and peak systolic velocity (PSV) were measured by US. Then, IMT/diameter ratio (IDR) was calculated. Risk factors associated with neurological SIE were analyzed by multivariate logistic regression.

Results

Totally, 295 patients were included, of whom 93 (31.5%) experienced neurological SIE, with common carotid artery involved (81.7%). Involved supra-aortic artery distribution (p=0.04) and number (p<0.01) differed between neurologic and non-neurologic SIE subjects, showing higher prevalence of common carotid and vertebral artery involvement in cases with neurological SIE and 57.1% neurological SIE patients having more than four involved arteries. The left carotid IMT (p=0.03) and IDR (p<0.01) differed between patients with and without neurological SIE. The left carotid IDR (cut-off value ≥0.55, odds ratio [OR] 4.46; 95% confidence interval [CI] 2.05-9.71; p<0.01) and PSV (≤76 cm/s, OR 3.38; 95% CI 1.62-7.04; p<0.01) and involved supra-aortic artery number (≥4, OR 3.16; 95% CI 1.54-6.47; p<0.01) were independently associated with neurological SIE.

Conclusion

The left carotid IDR, PSV and involved supra-aortic artery number would perform as valuable markers for recognizing neurological SIE in TAK patients with supra-aortic lesions.

References

[1]Kerr GS, Hallahan CW, Giordano J, et al. Takayasu arteritis. Ann Intern Med 1994; 120: 919-29.

[2]Cong XL, Dai SM, Feng X, et al. Takayasu’s arteritis: clinical features and outcomes of 125 patients in China. Clin Rheumatol 2010; 29: 973-81.

[3]Mirouse A, Biard L, Comarmond C, et al. Overall survival and mortality risk factors in Takayasu’s arteritis: a multicenter study of 318 patients. J Autoimmun 2019; 96: 35-9.

[4]Porter A, Youngstein T, Tombetti E, Mason JC. Biologic therapy in supra-aortic Takayasu arteritis can improve symptoms of cerebral ischaemia without surgical intervention. Rheumatology (Oxford) 2020; 59 Suppl 3: iii28-32.

[5]Michailidou D, Rosenblum JS, Rimland CA, Marko J, Ahlman MA, Grayson PC. Clinical symptoms and associated vascular imaging findings in Takayasu’s arteritis compared to giant cell arteritis. Ann Rheum Dis 2020; 79: 262-7.

[6]Schäfer VS, Jin L, Schmidt WA. Imaging for diagnosis, monitoring, and outcome prediction of large vessel vasculitides. Curr Rheumatol Rep 2020; 22: 76.

Disclosure of Interests

None declared

POS0799 BIOMARKER CHANGES IN TAKAYASU ARTERITIS AFTER TOFACITINIB TREATMENT AND THE MOLECULAR SIGNATURE ASSOCIATED WITH DISEASE CHARACTERISTICS

Background

Takayasu’s arteritis (TAK) is a chronic, non-specific, granulomatous macrovasculitis and its pathogenesis is still unclear. The increasing evidence indicated that multiple pathological process involved in the development of TAK. According to previous reports, multiple biomarkers representative different pathological process (1-3), However, which biomarker can closely reflect disease activity or vascular changes and whether these abnormal processes can be prevented by current therapies remained unknown.

Objectives

To analyze changes of serum cytokine, chemokine, and growth factor profiles in patients with Takayasu arteritis (TAK) after tofacitinib treatment and explore potential molecular signatures related with various disease characteristics

Methods

Seventeen patients from a TAK cohort treated with tofacitinib and 12 healthy controls were recruited in this study. Potential biomarkers with TAK including cytokines, MMPs, chemokines and growth factors were detected in these patients (0, 6, 12 months) and healthy controls. Molecular changes, disease activity, disease remission, and vascular imaging changes were analyzed in these patients after treatment. Furthermore, molecule signatures associated with these clinical features/outcomes were explored via radar plot and correlation analysis.

Results

At baseline, all the patients were in active status. Meanwhile, patients’ cytokines (PTX3, IL-6, IFN-γ), chemokines (IL-16, CCL22, CCL2), growth factor (VEGF) and MMP9 were significantly higher than those of healthy controls (all p<0.05), while FGF-2 was significantly lower in patients with TAK (p=0.02). After treatment, 94.12% of patients achieved complete remission at 6 and 12 months; patients’ ESR and CRP levels were significantly reduced at 6 months (p=0.02, p=0.046 respectively); vascular improvement were observed in 6 (35.29%) patients at 12 months. With regards to these molecules, IL-10 was increased at 6 months compared with its baseline level (p=0.007). No changes were observed in other cytokines, chemokines, or growth factors. Besides, the radar plot demonstrated that PTX3 was closely correlated with disease activity. In addition, patients with vascular imaging improvement had relatively higher baseline levels of TNFα, ESR, and CRP (p=0.04, p=0.056, p=0.07, respectively), lower CCL22, FGF, and PDGF-AB levels (p=0.056, p=0.06 and p=0.08 respectively) compared with patients without it.

Conclusion

Multiple molecules representative different pathological mechanism participated in the pathogenesis of TAK. PTX3 was a prominent marker for disease activity, and CCL22 may have a predictive value for vascular imaging changes.

References

[1]Dagna L, Salvo F, Tiraboschi M, et al. Pentraxin-3 as a marker of disease activity in Takayasu arteritis. Ann Intern Med. 2011;155(7):425-433. doi:10.7326/0003-4819-155-7-201110040-00005

[2]Sun Y, Kong X, Wu S, et al. YKL-40 as a new biomarker of disease activity in Takayasu arteritis. Int J Cardiol. 2019; 293: 231-237

[3]Dong H, Zhang Y, Zou Y, et al. Elevated chemokines concentration is associated with disease activity in Takayasu arteritis. Cytokine. 2021; 143: 155515

Disclosure of Interests

None declared

POS0491 A COMPREHENSIVE PROFILE OF CHEMOKINES IN THE PERIPHERAL BLOOD AND VASCULAR TISSUE OF PATIENTS WITH TAKAYASU ARTERITIS

Background

Takayasu arteritis (TAK) is a chronic granulomatous large vessel vasculitis with multiple immune cells involved [1]. In TAK, vascular lesions originate from the vascular adventitia. The vascular adventitia is rich in vasa vasorum, which can transport peripheral immune cells to active vascular lesions in the early stage of lesion development [2]. Thus, chemokines played critical roles in the pathogenesis of TAK. It has been reported that the levels of RANTES, CCL2, CCL20, CXCL8, and CXCL10 were elevated in TAK, and their levels were correlated with disease activity [3, 4]. However, the profile of chemokines in TAK has not been clearly elucidated.

Objectives

This study aimed to investigate chemokine profile in peripheral blood and vascular tissue of patients with TAK.

Methods

A total of 58 patients with TAK and 53 healthy controls were enrolled. Chemokine array assay was performed in five patients with TAK and three controls. Chemokines with higher levels were preliminarily validated in 20 patients and controls. The validated chemokines were further confirmed in another group of samples with 25 patients and 25 controls. Their expression and distribution were also examined in vascular tissue from 8 patients and 5 controls. Correlations between these chemokines and peripheral immune cells, cytokines, disease activity parameters were analyzed. Their serum changes were also investigated in these 45 patients after glucocorticoids and immunosuppressive treatment.

Results

Patients and controls were age and sex-matched. Twelve higher chemokines and 4 lower chemokines were found based on the chemokine array. After validation, increase of 5 chemokines were confirmed in patients with TAK, including CCL22, RANTES, CXCL16, CXCL11, and IL-16. Their expressions were also increased in vascular tissue of patients with TAK. In addition, levels of RANTES and IL-16 were positively correlated with peripheral CD3+CD4+ T cell numbers. Close localization of CCL22, CXCL11 or IL-16 with inflammatory cells were also observed in TAK vascular tissue. No correlations were found between these chemokines and cytokines (IL-6, IL-17, IFN-γ) or inflammatory parameters (ESR, CRP). No differences were observed regarding with these chemokines between active and inactive patients. After treatment, increase of CCL22 and decrease of RANTES, CXCL16 were found, while no changes were showed in levels of CXCL11 and IL-16.

Conclusion

CCL22, RANTES, CXCL16, CXCL11, and IL-16 were identified as the major chemokines involved in the recruitment of immune cells in the vascular tissue of patients with TAK. Additionally, the persistently high levels of CCL22, CXCL11, and IL-16 observed after treatment indicate their role in vascular chronic inflammation or fibrosis and demonstrate the need for developing more efficacious treatment options.

References

[1]Seyahi E. Takayasu arteritis: an update. Curr Opin Rheumatol. 2017 Jan;29(1):51-56.

[2]Corbera-Bellalta M, Planas-Rigol E, Lozano E, Terrades-García N, Alba MA, Prieto-González S, García-Martínez A, Albero R, Enjuanes A, Espígol-Frigolé G, Hernández-Rodríguez J, Roux-Lombard P, Ferlin WG, Dayer JM, Kosco-Vilbois MH, Cid MC. Blocking interferon γ reduces expression of chemokines CXCL9, CXCL10 and CXCL11 and decreases macrophage infiltration in ex vivo cultured arteries from patients with giant cell arteritis. Ann Rheum Dis. 2016 Jun;75(6):1177-86.

[3]Noris M, Daina E, Gamba S, Bonazzola S, Remuzzi G. Interleukin-6 and RANTES in Takayasu arteritis: a guide for therapeutic decisions? Circulation. 1999 Jul 6;100(1):55-60.

[4]Dong H, Zhang Y, Zou Y, Chen Y, Yue J, Liu H, Jiang X. Elevated chemokines concentration is associated with disease activity in Takayasu arteritis. Cytokine. 2021 Jul;143:155515.

Disclosure of Interests

None declared.

Functional analysis of the dihydroflavonol 4-reductase family of Camellia sinensis: exploiting key amino acids to reconstruct reduction activity

Anthocyanins and proanthocyanidins (PAs) are important types of flavonoids, plant secondary metabolites with a wide range of industrial and pharmaceutical applications. DFR (dihydroflavonol 4-reductase) is a pivotal enzyme that plays an important role in the flavonoid pathway. Here, four CsDFR genes were isolated from Camellia sinensis, and their overexpression was analyzed in vitro and in vivo. Based on transcription and metabolic analyses, CsDFR expression was closely consistent with catechins and PAs accumulation. Moreover, enzyme activity analyses revealed that the two recombinant proteins CsDFRa and CsDFRc exhibited DFR activity, converting dihydroflavonols into leucoanthocyanins in vitro, but CsDFRb1 and CsDFRb3 did not. CsDFRa and CsDFRc overexpression in AtDFR mutants (tt3) revealed that CsDFRs are involved in the biosynthesis of anthocyanins and PAs, as CsDFRa and CsDFRc restored not only the purple petiole phenotype but also the seed coat color. Site-directed mutagenesis revealed that the two amino acid residues S117 and T123 of CsDFRa play a prominent role in controlling DFR reductase activity. Enzymatic assays indicated that CsDFRa and CsDFRc exhibited a higher affinity for DHQ and DHK, respectively, whereas CsDFRb1^N120S and CsDFRb1^C126T exhibited a higher affinity for DHM. Our findings comprehensively characterize the DFRs from C. sinensis and shed light on their critical role in metabolic engineering.

[The clinical phenotype and gene analysis of syndromic deafness with PTPN11 gene mutation]

Objective: To analyze the clinical phenotype and screen the genetic mutations of hereditary deafness in three deaf families to clarify their molecular biology etiology. Methods: From January 2019 to January 2020, three deaf children and family members were collected for medical history, physical examination, audiology evaluation, electrocardiogram and cardiac color Doppler ultrasound, temporal bone CT examination, and peripheral blood DNA was obtained for high-throughput sequencing of deafness genes. Sanger sequencing was performed to verify the variant sites among family members. The pathogenicity of the variants was evaluated according to the American College of Medical Genetics and Genomics. Results: The probands in the three families had deafness phenotypes. In family 1, proband had multiple lentigines, special facial features, growth retardation, pectus carinatum, abnormal skin elasticity, cryptorchidism and other manifestations. In family 2, proband had special facial features, growth retardation and abnormal heart, and the proband in family 3 had growth retardation and abnormal electrocardiogram. Genetic testing of three families detected three heterozygous mutations in the PTPN11 gene: c.1391G>C (p.Gly464Ala), c.1510A>G (p.Met504Val), c.1502G>A (p.Arg501Lys). All three sites were missense mutations, and the mutation sites were highly conserved among multiple homologous species. Based on clinical manifestations and genetic test results, proband 1 was diagnosed with multiple lentigines Noonan syndrome, and probands 2 and 3 were diagnosed with Noonan syndrome. Conclusion: Missense mutations in the PTPN11 gene may be the cause of the disease in the three deaf families. This study enriches the clinical phenotype and mutation spectrum of the PTPN11 gene in the Chinese population.

Two UDP-Glycosyltransferases Catalyze the Biosynthesis of Bitter Flavonoid 7-O-Neohesperidoside through Sequential Glycosylation in Tea Plants

Flavonoid glycosides are typical bitter and astringent tasting compounds that contribute to the taste of tea beverages. However, the genes that contribute to the biosynthesis of bitter compounds (e.g., flavanone 7-O-neohesperidoside) in tea plants have yet to be identified. In this study, we identified 194 UDP-glycosyltransferases (UGTs) from the tea transcriptome database. Among them, two genes, CsUGT75L12 and CsUGT79B28, encoding flavonoid 7-O-glycosyltransferase and 7-O-glucoside(1→2)rhamnosyltransferase, respectively, were identified from Camellia sinensis. In vitro, the purified recombinant enzyme rCsUGT75L12 specifically transports the glucose unit from UDP-glucose to the 7-OH position of the flavonoid to produce the respective 7-O-glucoside. rCsUGT79B28 regiospecifically transfers a rhamnose unit from UDP-rhamnose to the 2″-OH position of flavonoid 7-O-glucosides to produce flavonoid 7-O-di-glycosides. Additionally, the expression profiles of the two CsUGTs were correlated with the accumulation patterns of 7-O-glucoside and 7-O-neohesperidoside, respectively, in tea plants. These results indicated that the two CsUGTs are involved in the biosynthesis of bitter flavonoid 7-O-neohesperidoside through the sequential glucosylation and rhamnosylation of flavonoids in C. sinensis. Taken together, our findings provided not only molecular insights into flavonoid di-glycoside metabolism in tea plants but also crucial molecular markers for controlling the bitterness and astringent taste of tea.

Effects of lactic acid-producing bacteria as direct-fed microbials on the ruminal microbiome

The objective of this study was to evaluate ruminal microbiome changes associated with feeding Lactobacillus plantarum GB-LP1 as direct-fed microbials (DFM) in high-producing dairy cow diets. A dual-flow continuous culture system was used in a replicated 4 × 4 Latin square design. A basal diet was formulated to meet the requirements of a cow producing 45 kg of milk per day (16% crude protein and 28% starch). There were 4 experimental treatments: the basal diet without any DFM (CTRL); a mixture of Lactobacillus acidophilus, 1 × 10⁹ cfu/g, and Propionibacterium freudenreichii, 2 × 10⁹ cfu/g [MLP = 0.01% of diet dry matter (DM)]; and 2 different levels of L. plantarum, 1.35 × 10⁹ cfu/g (L1 = 0.05% and L2 = 0.10% of diet DM). Bacterial samples were collected from the fluid and particulate effluents before feeding and at 2, 4, 6, and 8 h after feeding; a composite of all time points was made for each fermentor within their respective fractionations. Bacterial community composition was analyzed through sequencing the V4 region of the 16S rRNA gene using the Illumina MiSeq platform. Sequenced data were analyzed on DADA2, and statistical analyses were performed in R (RStudio 3.0.1, https://www.r-project.org/) and SAS 9.4 (SAS Institute Inc.); orthogonal contrasts were used to compare treatments. Different than in other fermentation scenarios (e.g., silage or beef cattle high-grain diets), treatments did not affect pH or lactic acid concentration. Effects were mainly from overall DFM inclusion, and they were mostly observed in the fluid phase. The relative abundance of the phylum Firmicutes, family Lachnospiraceae, and 6 genera decreased with DFM inclusion, with emphasis on Butyrivibrio_2, Saccharofermentans, and Ruminococcus_1 that are fibrolytic and may display peptidase activity during fermentation. Lachnospiraceae_AC2044_group and Lachnospiraceae_XPB1014_group also decreased in the fluid phase, and their relative abundances were positively correlated with NH₃-N daily outflow from the fermentors. Specific effects of MLP and L. plantarum were mostly in specific bacteria associated with proteolytic and fibrolytic functions in the rumen. These findings help to explain why, in the previous results from this study, DFM inclusion decreased NH₃-N concentration without altering pH and lactic acid concentration.

Contrarians Synchronize beyond the Limit of Pairwise Interactions

We give evidence that a population of pure contrarian globally coupled D-dimensional Kuramoto oscillators reaches a collective synchronous state when the interplay between the units goes beyond the limit of pairwise interactions. Namely, we will show that the presence of higher-order interactions may induce the appearance of a coherent state even when the oscillators are coupled negatively to the mean field. An exact solution for the description of the microscopic dynamics for forward and backward transitions is provided, which entails imperfect symmetry breaking of the population into a frequency-locked state featuring two clusters of different instantaneous phases. Our results contribute to a better understanding of the powerful potential of group interactions entailing multidimensional choices and novel dynamical states in many circumstances, such as in social systems.

[Pravelance and risk factors of frailty in community-dwelling Chinese elderly population]

OBJECTIVE

To investigate the incidence of frailty in community-dwelling Chinese elderly population and explore the risk factors and protective factors of frailty in the elderly.

METHODS

This study was conducted based on the 2011-2015 survey data provided by the China Health and Retirement Longitudinal Study (CHARLS). A research cohort was established consisting of non-debilitated elderly individuals aged 60 years and above at the 2011 baseline survey to assess the incidence of debilitation in the cohort population followed up till 2015. A nested case-control study was conducted to analyze the contributing factors to frailty in the elderly.

RESULTS

In this study, the cohort population was followed up for a total of 14351 person-years. A total of 248 individuals had newly developed frailty during the follow-up period, resulting in an incidence of 17.28/1000 person-years; the incidence was lower in elderly men than in elderly women (14.63/1000 vs 20.14/1000 person-years). The incidence of debilitation increased progressively with ageing: 8.90/1000 person-years in 60-64 years group, 16.77/ 1000 person-years in 65-69 years group, 24.04/1000 person-years in 70-74 years group, and 64.67/1000 person-years in 80 years or older group. Multivariate conditional logistic regression analysis showed that depressive symptoms (OR=2.534, 95% CI: 1.714-3.748), smoking (OR=1.713, 95% CI: 1.081-2.715) and self-care difficulties (OR=1.684, 95% CI: 1.155-2.456) were the risk factors contributing to frailty in the elderly; the marital status (unmarried, divorced and widowed) (OR=0.432, 95%CI: 0.278-0.673), a high cognitive function score (OR=0.919, 95% CI: 0.870-0.970), a primary school education (OR=0.453, 95% CI: 0.254- 0.806) and drinking (OR=0.520, 95%CI: 0.323-0.837) were the protective factors against frailty in the elderly.

CONCLUSIONS

The incidence of frailty in community-dwelling Chinese elderly population is lower than the average incidence globally. The incidence of frailty in the elderly differs with gender and age, and depressive symptoms, smoking, and self-care difficulties are the main risk factors for frailty in the community-dwelling elderly.