Observation of an a_{0}-like State with Mass of 1.817 GeV in the Study of D_{s}^{+}→K_{S}^{0}K^{+}π^{0} Decays

Using e^{+}e^{-} annihilation data corresponding to an integrated luminosity of 6.32  fb^{-1} collected at center-of-mass energies between 4.178 and 4.226 GeV with the BESIII detector, we perform the first amplitude analysis of the decay D_{s}^{+}→K_{S}^{0}K^{+}π^{0} and determine the relative branching fractions and phases for intermediate processes. We observe an a_{0}-like state with mass of 1.817 GeV in its decay to K_{S}^{0}K^{+} for the first time. In addition, we measure the ratio {B[D_{s}^{+}→K[over ¯]^{*}(892)^{0}K^{+}]/B[D_{s}^{+}→K[over ¯]^{0}K^{*}(892)^{+}]} to be 2.35_{-0.23stat}^{+0.42}±0.10_{syst}. Finally, we provide a precision measurement of the absolute branching fraction B(D_{s}^{+}→K_{S}^{0}K^{+}π^{0})=(1.46±0.06_{stat}±0.05_{syst})%.

Precise Measurements of Decay Parameters and CP Asymmetry with Entangled Λ-Λ[over ¯] Pairs

Based on 10 billion J/ψ events collected at the BESIII experiment, a search for CP violation in Λ decay is performed in the difference between CP-odd decay parameters α_{-} for Λ→pπ^{-} and α_{+} for Λ[over ¯]→p[over ¯]π^{+} by using the process e^{+}e^{-}→J/ψ→ΛΛ[over ¯]. With a five-dimensional fit to the full angular distributions of the daughter baryon, the most precise values for the decay parameters are determined to be α_{-}=0.7519±0.0036±0.0024 and α_{+}=-0.7559±0.0036±0.0030, respectively. The Λ and Λ[over ¯] averaged value of the decay parameter is extracted to be α_{avg}=0.7542±0.0010±0.0024 with unprecedented accuracy. The CP asymmetry A_{CP}=(α_{-}+α_{+})/(α_{-}-α_{+}) is determined to be -0.0025±0.0046±0.0012, which is one of the most precise measurements in the baryon sector. The reported results for the decay parameter will play an important role in the studies of the polarizations and CP violations for the strange, charmed and beauty baryons.

First Observation of the Direct Production of the χ_{c1} in e^{+}e^{-} Annihilation

We study the direct production of the J^{PC}=1^{++} charmonium state χ_{c1}(1P) in electron-positron annihilation by carrying out an energy scan around the mass of the χ_{c1}(1P). The data were collected with the BESIII detector at the BEPCII collider. An interference pattern between the signal process e^{+}e^{-}→χ_{c1}(1P)→γJ/ψ→γμ^{+}μ^{-} and the background processes e^{+}e^{-}→γ_{ISR}J/ψ→γ_{ISR}μ^{+}μ^{-} and e^{+}e^{-}→γ_{ISR}μ^{+}μ^{-} is observed by combining all the data samples. The χ_{c1}(1P) signal is observed with a significance of 5.1σ. This is the first observation of a C-even state directly produced in e^{+}e^{-} annihilation. The electronic width of the χ_{c1}(1P) resonance is determined to be Γ_{ee}=(0.12_{-0.08}^{+0.13})  eV, which is of the same order of magnitude as theoretical calculations.

Evidence for a Neutral Near-Threshold Structure in the K_{S}^{0} Recoil-Mass Spectra in e^{+}e^{-}→K_{S}^{0}D_{s}^{+}D^{*-} and e^{+}e^{-}→K_{S}^{0}D_{s}^{*+}D^{-}

We study the processes e^{+}e^{-}→K_{S}^{0}D_{s}^{+}D^{*-} and e^{+}e^{-}→K_{S}^{0}D_{s}^{*+}D^{-}, as well as their charge conjugated processes, at five center-of-mass energies between 4.628 and 4.699 GeV, using data samples corresponding to an integrated luminosity of 3.8  fb^{-1} collected by the BESIII detector at the BEPCII storage ring. Based on a partial reconstruction technique, we find evidence of a structure near the thresholds for D_{s}^{+}D^{*-} and D_{s}^{*+}D^{-} production in the K_{S}^{0} recoil-mass spectrum, which we refer to as the Z_{cs}(3985)^{0}. Fitting with a Breit-Wigner line shape, we find the mass of the structure to be (3992.2±1.7±1.6)  MeV/c^{2} and the width to be (7.7_{-3.8}^{+4.1}±4.3)  MeV, where the first uncertainties are statistical and the second are systematic. The significance of the Z_{cs}(3985)^{0} signal is found to be 4.6σ including both the statistical and systematic uncertainty. We report the Born cross section multiplied by the branching fraction at different energy points. The mass of the Z_{cs}(3985)^{0} is close to that of the Z_{cs}(3985)^{+}. Assuming SU(3) symmetry, the cross section of the neutral channel is consistent with that of the charged one. Hence, we conclude that the Z_{cs}(3985)^{0} is the isospin partner of the Z_{cs}(3985)^{+}.

Observation of Resonance Structures in e^{+}e^{-}→π^{+}π^{-}ψ_{2}(3823) and Mass Measurement of ψ_{2}(3823)

Using a data sample corresponding to an integrated luminosity of 11.3  fb^{-1} collected at center-of-mass energies from 4.23 to 4.70 GeV with the BESIII detector, we measure the product of the e^{+}e^{-}→π^{+}π^{-}ψ_{2}(3823) cross section and the branching fraction B[ψ_{2}(3823)→γχ_{c1}]. For the first time, resonance structure is observed in the cross section line shape of e^{+}e^{-}→π^{+}π^{-}ψ_{2}(3823) with significances exceeding 5σ. A fit to data with two coherent Breit-Wigner resonances modeling the sqrt[s]-dependent cross section yields M(R_{1})=4406.9±17.2±4.5  MeV/c^{2}, Γ(R_{1})=128.1±37.2±2.3  MeV, and M(R_{2})=4647.9±8.6±0.8  MeV/c^{2}, Γ(R_{2})=33.1±18.6±4.1  MeV. Though weakly disfavored by the data, a single resonance with M(R)=4417.5±26.2±3.5  MeV/c^{2}, Γ(R)=245±48±13  MeV is also possible to interpret data. This observation deepens our understanding of the nature of the vector charmoniumlike states. The mass of the ψ_{2}(3823) state is measured as (3823.12±0.43±0.13)  MeV/c^{2}, which is the most precise measurement to date.

Rational development of mycobacteria cell factory for advancing the steroid biomanufacturing

Steroidal resource occupies a vital proportion in the pharmaceutical industry attributing to their important therapeutic effects on fertility, anti-inflammatory and antiviral activities. Currently, microbial transformation from phytosterol has become the dominant strategy of steroidal drug intermediate synthesis that bypasses the traditional chemical route. Mycobacterium sp. serve as the main industrial microbial strains that are capable of introducing selective functional modifications of steroidal intermediate, which has become an indispensable platform for steroid biomanufacturing. By reviewing the progress in past two decades, the present paper concentrates mainly on the microbial rational modification aspects that include metabolic pathway editing, key enzymes engineering, material transport pathway reinforcement, toxic metabolic intermediates removal and byproduct reconciliation. In addition, progress on omics analysis and direct genetic manipulation are summarized and classified that may help reform the industrial hosts with more efficiency. The paper provides an insightful present for steroid biomanufacturing especially on the current trends and prospects of mycobacteria.

Observation of a State X(2600) in the π^{+}π^{-}η' System in the Process J/ψ→γπ^{+}π^{-}η'

Based on (10087±44)×10^{6}  J/ψ events collected with the BESIII detector, the process J/ψ→γπ^{+}π^{-}η^{'} is studied using two largest decay channels of the η^{'} meson, η^{'}→γπ^{+}π^{-} and η^{'}→ηπ^{+}π^{-}, η→γγ. A new resonance, which we denote as the X(2600), is observed with a statistical significance larger than 20σ in the π^{+}π^{-}η^{'} invariant mass spectrum, and it has a connection to a structure around 1.5  GeV/c^{2} in the π^{+}π^{-} invariant mass spectrum. A simultaneous fit on the π^{+}π^{-}η^{'} and π^{+}π^{-} invariant mass spectra with the two η^{'} decay modes indicates that the mass and width of the X(2600) state are 2618.3±2.0_{-1.4}^{+16.3}  MeV/c^{2} and 195±5_{-17}^{+26}  MeV, where the first uncertainties are statistical, and the second systematic.

Observation of J/ψ Electromagnetic Dalitz Decays to X(1835), X(2120), and X(2370)

Using a sample of about 10^{10}  J/ψ events collected at a center-of-mass energy sqrt[s]=3.097  GeV with the BESIII detector, the electromagnetic Dalitz decays J/ψ→e^{+}e^{-}π^{+}π^{-}η^{'}, with η^{'}→γπ^{+}π^{-} and η^{'}→π^{+}π^{-}η, have been studied. The decay J/ψ→e^{+}e^{-}X(1835) is observed with a significance of 15σ, and also an e^{+}e^{-} invariant-mass dependent transition form factor of J/ψ→e^{+}e^{-}X(1835) is presented for the first time. The intermediate states X(2120) and X(2370) are also observed in the π^{+}π^{-}η^{'} invariant-mass spectrum with significances of 5.3σ and 7.3σ. The corresponding product branching fractions for J/ψ→e^{+}e^{-}X, X→π^{+}π^{-}η^{'} [X=X(1835), X(2120), and X(2370)] are reported.

[Clinical and genetic characteristics of congenital isolated adrenocorticotropic hormone deficiency]

Objective: To investigate the clinical and genetic characteristics of congenital isolated adrenocorticotropic hormone (ACTH) deficiency. Methods: The clinical and laboratory characteristics of 5 cases with congenital isolated ACTH deficiency diagnosed in the Department of Endocrinology of the Children's Hospital, Capital Institute of Pediatrics from January 2019 to March 2021 were retrospectively analyzed. The general conditions, clinical manifestations, laboratory examinations, genetic charcteistics, treatment and follow-up (up to October 2021) were analyzed. Results: Of the 5 cases, 1 was female and 4 were males, aged from 13 months to 6 years at the time of consultation. The symptoms of hypoglycemia and convulsion were presented in infancy, and 4 cases had infantile cholestasis. Glucose level of 5 cases ranged from 0.79-2.20 mmol/L, ACTH ranged from <1.00-4.17 ng/L, and cortisol ranged from 0.2-3.8 μg/L. Whole exon sequencing revealed that 3 cases carried homozygous TBX19 variations, and 2 cases had compound heterozygous TBX19 variations, including 3 variants that had been reported before and 3 novel variants were found. After the diagnosis was confirmed, all the cases were treated with hydrocortisone. Hypoglycemia was all corrected during the follow-up, and 4 cases no longer had convulsions. Conclusion: Congenital isolated ACTH deficiency should be considered in neonates and infants with cholestasis and hypoglycemia, and the diagnosis can be confirmed by genetic testing.

Rerouting Fluxes of the Central Carbon Metabolism and Relieving Mechanism-Based Inactivation of l-Aspartate-α-decarboxylase for Fermentative Production of β-Alanine in Escherichia coli

β-Alanine, with the amino group at the β-position, is an important platform chemical that has been widely applied in pharmaceuticals and feed and food additives. However, the current modest titer and productivity, increased fermentation cost, and complicated operation are the challenges for producing β-alanine by microbial fermentation. In this study, a high-yield β-alanine-producing strain was constructed by combining metabolic engineering, protein engineering, and fed-batch bioprocess optimization strategies. First, an aspartate-α-decarboxylase from Bacillus subtilis was introduced in Escherichia coli W3110 to construct an initial β-alanine-producing strain. Production of β-alanine was obviously increased to 4.36 g/L via improving the metabolic flux and reducing carbon loss by rerouting fluxes of the central carbon metabolism. To further increase β-alanine production, mechanism-based inactivation of aspartate-α-decarboxylase was relieved by rational design to maintain the productivity at a high level in β-alanine fed-batch fermentation. Finally, fed-batch bioprocess optimization strategies were used to improve β-alanine production to 85.18 g/L with 0.24 g/g glucose yield and 1.05 g/L/h productivity in fed-batch fermentation. These strategies can be effectively used in the construction of engineered strains for β-alanine and production of its derivatives, and the final engineered strain was a valuable microbial cell factory that can be used for the industrial production of β-alanine.

[Analysis on psychoactive substances use in men who have sex with men in Tianjin]

Objective: To understand the use of psychoactive substances and its related factors in men who have sex with men (MSM) in Tianjin. Methods: A cross-sectional survey was conducted in MSM recruited in Tianjin by snowball sampling from September 2017 to December 2020, the information about their social demographic information, use of psychoactive substances and behavioral characteristics were collected, meanwhile the blood samples were taken from them for HIV/syphilis detections. Multivariate logistic regression was used to explore related factors about psychoactive substances use. Results: A total of 9 218 MSM were included in the study, in whom 43.5% (4 013/9 218) had ever used psychoactive substances, including 92.6% (3 718/4 013)who used Rush and 17.2% (692/4 013) who used multi substances. Multivariate analysis showed that, the OR of psychoactive substances use in MSM who were in Han ethnic group was 0.68 (95%CI:0.51-0.91) compared with those who were in minor ethnic group; the OR of psychoactive substances use in MSM who were married or cohabited, divorced or widowed were 0.65 (95%CI: 0.57-0.71), 0.80 (95%CI: 0.65-0.97) respectively compared with those who were unmarried; the OR of psychoactive substances use in MSM who had the first homosexual sex at age of ≥30 years was 0.57 (95%CI: 0.44-0.74) compared with those who had the first homosexual sex at age of <30 years; the OR of psychoactive substances use in local MSM in Tianjin was 1.12 (95%CI: 1.03-1.23) compared with those who were not local residents in Tianjin; the OR of psychoactive substances use in MSM with education level of college or above was 1.29 (95%CI: 1.12-1.49) compared with those with education level of junior middle school or below; the OR of psychoactive substances use in MSM who had anal sex in the past six months was 1.93 (95%CI: 1.34-2.77) compared with those who had no anal sex; the OR of psychoactive substances use in MSM who had >2 homosexual partners in the last week was 1.62 (95%CI: 1.41-1.87) compared with those who had ≤2 homosexual partners; the OR of psychoactive substances use in MSM who had homosexual commercial sex in the past six months was 1.99 (95%CI: 1.62-2.45) compared with those who had no homosexual commercial sex; the OR of psychoactive substances use in MSM who had sexually transmitted diseases in the last year was 2.39 (95%CI: 1.82-3.12) compared with those who had no sexually transmitted diseases and the OR of psychoactive substances use in MSM who received peer education services in the last year was 1.63 (95%CI: 1.50-1.78) compared with those who received no peer education services. Conclusion: The prevalence of psychoactive substances use is high in MSM in Tianjin, and there are many influencing factors. It is necessary to conduct targeted interventions according to the influencing factors.

Module engineering coupled with omics strategies for enhancing D-pantothenate production in Escherichia coli

Biosynthesis of D-pantothenate has been widely studied as D-pantothenate is one kind of important vitamins used in food and pharmaceuticals. However, the engineered strain for D-pantothenate production was focused solely on the main biosynthetic pathway, while other important factors such as one carbon unit were ignored. Here the systematic modular engineering on different factors coupled with omics analysis were studied in Escherichia coli for efficient D-pantothenate production. Through reinforcing the precursor pool, refactoring the one carbon unit generation pathway, optimization of reducing power and energy supply, the D-pantothenate titer reached 34.12 g/L with the yield at 0.28 g/g glucose under fed-batch fermentation in 5-L bioreactor. With a further comparative transcriptome and metabolomics studies, the addition of citrate was implemented and 45.35 g/L D-pantothenate was accumulated with a yield of 0.31 g/g glucose. The systematic modular engineering coupled with omics studies provide useful strategies for the industrial production of D-pantothenate.

Two-Photon Excited Fluorescent 3,3'-Diamino-5,5'-Diboryl-2,2'-Bithienyls Featuring a Quadrupolar Structure

The quest for fluorophores exhibiting large two-photon absorption cross sections and high fluorescence efficiency is an important topic. Two 2,2'-bithienyl derivatives are disclosed which contain two N,N-disubstituted amino and two dimesitylboryl groups at 3,3'- and 5,5'-positions, respectively. Despite the great steric effect of amino groups, the bithienyl skeleton still adopts a coplanar geometry. Herein, they are characterized by a quadrupolar structure and display good fluorescence efficiency and large two-photon absorption cross sections up to 473 GM.

High Throughput Screening of Signal Peptide Library with Novel Fluorescent Probe

Nitrile hydratase (NHase) is an excellent bio-catalyst for the synthesis of amide compounds, was composed of two heterologous subunits. However, the secretory expression of NHase has been difficult to achieve because of its complex expression mechanism. In this work, a novel fluorescent probe Rho-IDA-CoII was synthesized by the one-pot method. Rho-IDA-CoII could specifically label His-tagged proteins in vitro specifically, such as staining in-gel, western blot and ELISA. Furthermore, Rho-IDA-CoII combined with dot blot could quantitatively detect His-tagged proteins between 1 - 10 pmol and perform high-throughput screening for the NHase signal peptide library. The recombinant Bacillus subtilis WB800/phoB-HBA with the extracellular expression of NHase was screened from ca. 6500 clones. After optimization of fermentation conditions, the NHase activity in the culture supernatant reached to 17.34 ± 0.16 U/mL. It was the first time to express secretory NHase in Bacillus subtilis successfully.

Observation of the Singly Cabibbo Suppressed Decay Λ_{c}^{+}→nπ^{+}

The singly Cabibbo-suppressed decay Λ_{c}^{+}→nπ^{+} is observed for the first time with a statistical significance of 7.3σ by using 3.9  fb^{-1} of e^{+}e^{-} collision data collected at center-of-mass energies between 4.612 and 4.699 GeV with the BESIII detector at BEPCII. The branching fraction of Λ_{c}^{+}→nπ^{+} is measured to be (6.6±1.2_{stat}±0.4_{syst})×10^{-4}. By taking the upper limit of branching fractions of Λ_{c}^{+}→pπ^{0} from the Belle experiment, the ratio of branching fractions between Λ_{c}^{+}→nπ^{+} and Λ_{c}^{+}→pπ^{0} is calculated to be larger than 7.2 at the 90% confidence level, which disagrees with most predictions of the available phenomenological models. In addition, the branching fractions of the Cabibbo-favored decays Λ_{c}^{+}→Λπ^{+} and Λ_{c}^{+}→Σ^{0}π^{+} are measured to be (1.31±0.08_{stat}±0.05_{syst})×10^{-2} and (1.22±0.08_{stat}±0.07_{syst})×10^{-2}, respectively, which are consistent with previous results.

Tuning the catalytic performances of a sucrose isomerase for production of isomaltulose with high concentration

Obtaining a sucrose isomerase (SIase) with high catalytic performance is of great importance in industrial production of isomaltulose (a reducing sugar). In order to obtain such SIase mutant, a high-throughput screening system in microtiter plate format was developed based on a widely used 2,4-dinitrosalicylic acid (DNS) method for determination of reducing sugar. An SIase from Erwinia sp. Ejp617 (ErSIase) was selected to improve its catalytic efficiency. After screening of ~ 8000 mutants from a random mutagenesis library, Q209 and R456 were identified as beneficial positions. Saturation mutagenesis of the two positions resulted in a double-site mutant ErSIase_Q209S-R456H that showed the highest catalytic efficiency, and its specific activity reached 684 U/mg that is 17.5-fold higher than that of the wild-type ErSIase. By employing the lyophilized Escherichia coli (E. coli) cells harboring ErSIase_Q209S-R456H, a high space-time yield (STY = 3.9 kg/(L·d)) was achieved toward 600 g/L sucrose. Furthermore, the in silico analysis suggested that the hydrogen bond network was improved and steric hindrance was reduced due to the beneficial substitutions.Key points• A sucrose isomerase mutant with high catalytic efficiency was obtained.• The highest space-time yield was achieved toward high-concentration sucrose.• The optimized H-bond network contributed to the enhanced catalytic efficiency.

[Analysis on incidence trend of liver cancer in China, 2005-2016]

Objective: To understand the incidence trend of liver cancer in China from 2005 to 2016, and explore the correlation between the incidence trend of liver cancer and the incidence trend of hepatitis B. Methods: The incidence data of liver cancer in China from 2005 to 2016 were collected from the Annual Report of Cancer Registry in China. The incidence data of hepatitis B were collected from China Public Health Science Data Center. World standardized incidence rate (WSR) was calculated according to the World Segi's population. Joinpoint regression model was used to analyze the trend of WSR of liver cancer [measured by average annual percentage change (AAPC)]. The age-period-cohort model was fitted to analyze the age, period and cohort effects in people aged 20- years and above. Pearson correlation coefficient was used to explore the correlation between the incidence of liver cancer and the incidence of hepatitis B. Results: The crude incidence of liver cancer in China showed a trend of first increase before 2009 and then relatively stable. The world standardized morbidity rate of liver cancer in China decreased from 19.11 per 100 000 in 2005 to 17.74 per 100 000 in 2016 (AAPC=-0.5%, 95%CI: -1.3%-0.3%, P=0.240). The incidence of liver cancer in male decreased significantly (AAPC=-1.0%, 95%CI: -1.5%--0.5%, P=0.001). The incidence of liver cancer in women increased from 2005 to 2010 [annual percentage change (APC)=1.7%, 95%CI: -0.1%-3.4%, P=0.059] but showed a significant decrease trend from 2010 to 2016 (APC=-1.6%, 95%CI: -2.3%--1.0%, P=0.001). From 2005 to 2016, the incidence of liver cancer showed a decreasing trend in urban areas (AAPC=-0.3%, 95%CI: -0.8%-0.3%, P=0.316) and rural areas (AAPC=-3.9%, 95%CI: -4.4%--3.3%, P<0.001). Risk for liver cancer increased with age, while the period effect showed a trend of first increase then decrease and cohort effect showed a decrease trend. The morbidity rates of both hepatitis B and liver cancer showed decrease trends from 2009 to 2016, and there was a significant correlation (r=0.71, 95%CI: 0.01-0.94, P=0.048). Conclusions: From 2005 to 2016, the morbidity rate of liver cancer in China showed a decrease trend, and there were significant gender and urban-rural area specific differences. Age effect had a great impact on the risk for liver cancer. With the progress of population aging in China, liver cancer is still a public health problem, to which close attention needs to be paid.

The duration of beta-blocker therapy and outcomes in patients without heart failure or left ventricular systolic dysfunction after acute myocardial infarction: A multicenter prospective cohort study

Background

The duration of beta‐blocker therapy in patients without heart failure (HF) or left ventricular systolic dysfunction after acute myocardial infarction (AMI) is unclear.

Hypothesis

Continuous beta‐blocker therapy is associated with an improved prognosis.

Methods

This is a prospective, multicenter, cohort study. One thousand four hundred and eighty‐three patients eventually met the inclusion criteria. The study groups included the continuous beta‐blocker therapy group (lasted ≥6 months) and the discontinuous beta‐blocker therapy group (consisting of the no‐beta‐blocker therapy group and the beta‐blocker therapy <6 months group). The inverse probability treatment weighting was used to control confounding factors. The study tried to learn the role of continuous beta‐blocker therapy on outcomes. The median duration of follow‐up was 13.0 months. The primary outcomes were cardiac death and major adverse cardiovascular events (MACE). The secondary outcomes were all‐cause death, stroke, unstable angina, rehospitalization for HF, and recurrent myocardial infarction (MI).

Results

Compared with discontinuous beta‐blocker therapy, continuous beta‐blocker therapy was associated with a reduced risk of unstable angina, recurrent MI, and MACE (hazard ratio [HR]: 0.51; 95% CI: 0.32–0.82; p = 0.006); but this association was not available for cardiac death (HR: 0.57; 95% CI: 0.24–1.36; p = 0.206). When compared to the subgroups of no‐beta‐blocker therapy and beta‐blocker therapy <6 months, respectively, continuous beta‐blocker therapy was still observed to be associated with a reduced risk of unstable angina, recurrent MI, and MACE.

Conclusions

Continuous beta‐blocker therapy was associated with a reduced risk of unstable angina or recurrent MI or MACE in patients without HF or left ventricular systolic dysfunction after AMI.

Measurement of the Cross Section for e^{+}e^{-}→Hadrons at Energies from 2.2324 to 3.6710 GeV

Based on electron-positron collision data collected with the BESIII detector operating at the Beijing Electron-Positron Collider II storage rings, the value of R≡σ(e^{+}e^{-}→hadrons)/σ(e^{+}e^{-}→μ^{+}μ^{-}) is measured at 14 center-of-mass energies from 2.2324 to 3.6710 GeV. The resulting uncertainties are less than 3.0% and are dominated by systematic uncertainties.

Glutaminolysis is required in maintaining immune regulatory functions in B cells

IL-10-expressing regulatory B cells (B10 cells) are dysfunctional in patients with many immune disorders. The underlying mechanism remains to be further elucidated. Glutamine is an essential nutrient for cell metabolism. This study aims to elucidate the role of glutaminolysis in maintaining the immune regulatory capacity in B10 cells. Peripheral blood samples were collected from 50 patients with allergic rhinitis and 50 healthy control subjects. B cells were isolated from blood samples by cell sorting with flow cytometry. The role of glutaminolysis in regulating B10 cell activities was assessed by immunological and biochemical approaches. The results showed that B cells from patients with allergic rhinitis expressed low levels of the transporter of glutamine and neutral amino acid. Glutaminolysis was required in the IL-10 expression in B cells. The glutamine catabolism was required in B10 cell generation. The mTOR activation mediated the glutaminolysis-associated B10 cell induction, and the suppression of the B cell glycogen synthase kinase-3 (GSK3) activation. GSK3 activation suppressed IL-10 expression in B cells. Inhibition of GSK3 enhanced IL-10 expression in B cells and alleviated experimental allergic rhinitis by generating immune competent type 1 regulatory T cells.

Immobilization of Sucrose Isomerase from Erwinia sp. with Graphene Oxide and Its Application in Synthesizing Isomaltulose

Sucrose isomerase (SIase) is a key enzyme used for the production of isomaltulose from sucrose. In this study, an SIase gene from Erwinia sp. Ejp617 (ErSIase) was heterologously expressed in Escherichia coli BL21(DE3), and the recombinant ErSIase was served as biocatalyst combined with the graphene oxide (GO) as carrier for ErSIase immobilization. The Fourier transform infrared spectroscopy, transmission electron microscope, and confocal laser microscopy analyses showed that ErSIase was successfully immobilized on the surface of GO to form ErSIase-GO. The loading capacity of ErSIase on GO reached up to 460 mg/g with a specific activity of 727.04 U/mg protein when the optimal immobilization time of 12 h and the ErSIase/GO ratio of 7.4:4 (w/w) were applied. A high conversion rate of 95.3% was reached from sucrose to isomaltulose using ErSIase-GO as biocatalyst with 600 g/L sucrose as substrate, after 180 min at 40 °C and pH 6.0. Moreover, stabilities of the immobilized ErSIase-GO in the aspects of thermal, pH, and storage were improved, and its activity after 10 batches still remained around 80% under the optimal conditions. The Km value of ErSIase-GO was 29.32 mM, and the kcat/Km was increased to 27.34 s-1 mM-1 when 0.1% (w/v) detergent NP40 was added. These results indicated that the ErSIase was well immobilized onto GO, and the ErSIase-GO is a promising biocatalyst with high operational stability and catalytic activity for industrial production of isomaltulose.

[The Relationship between the Expressions of CD33 and CD13 and the Prognosis of Patients with Multiple Myeloma]

OBJECTIVE

To investigate the expressions of CD33 and CD13 in newly diagnosed multiple myeloma (MM) patients and its relationship with prognosis.

METHODS

It was retrospectively observed that the expression of CD33 and CD13 in 121 MM patients who were newly diagnosed from January 2014 to January 2020, and the relationship between the expressions of CD33 and CD13 and patients prognosis was analyzed.

RESULTS

Among the 121 newly diagnosed MM patients, there were 30 patients (24.8%) in the CD33⁺ group and 12 patients (9.9%) in the CD13⁺ group. Kaplan-Meier analysis showed that, compared with the CD33^- group, the progression-free survival (PFS) time and overall survival (OS) time were significantly shortened in MM patients in CD33⁺ group (PFS 17.5 vs 23 months, P=0.000; OS 18.5 vs 25 months, P=0.000); and the PFS time and OS time of MM patients in the CD13⁺ group were also significantly shortened than those in CD13^- group (PFS 21 vs 22 months, P=0.012; OS 25 vs 26 months, P=0.006). Cox regression analysis showed that CD33 and CD13 were independent adverse prognostic factors in MM patients (CD33: P=0.000;CD13: P=0.003).

CONCLUSION

CD33 and CD13 are prognostic risk factors in patients with MM.

First Measurement of Polarizations in the Decay D^{0}→ωφ

Using a data sample corresponding to an integrated luminosity of 2.93  fb^{-1} collected at a center-of-mass energy sqrt[s]=3.773  GeV by the BESIII detector, the decay D^{0}→ωϕ is observed for the first time. The branching fraction is measured to be (6.48±0.96±0.40)×10^{-4} with a significance of 6.3σ, where the first and second uncertainties are statistical and systematic, respectively. An angular analysis reveals that the ϕ and ω mesons from the D^{0}→ωϕ decay are transversely polarized. The 95% confidence level upper limit on longitudinal polarization fraction is set to be less than 0.24, which is inconsistent with current theoretical expectations and challenges our understanding of the underlying dynamics in charm meson decays.