[Establishment of acute graft-versus-host disease model after non-myeloablative haploidentical peripheral blood stem cell transplantation in aged mice].

Objective: To establish an acute graft-versus-host disease (aGVHD) model in aged mice after non-myeloablative haploidentical peripheral blood stem cell transplantation (haplo-PSCT). Methods: C57BL/6 (H-2b) male mice aged 6-8 weeks were used as donor mice, and CB6F1 (H-2b×d) female mice aged 14-16 months were used as recipient mice. The donor mice were injected subcutaneously with rehuman granulocyte-colony stimulating factor (rhG-CSF) 5 days before transplantation for hematopoietic stem cell mobilization.The recipient mice were divided into control group (CG), spleen cell low-dose group (SL), spleen cell medium-dose group (SM) and spleen cell high-dose group (SH) according to random number table method, with 16 rats in each group, all of which received total linear accelerator X-ray irradiation (TBI) with a total dose of 6 Gy. Peripheral blood mononuclear cells (PBMC) and spleen cells of different doses (0.5×107/each, 1.0×107/each and 2.0×107/each in SL group, SM group and SH group, respectively) were transfused through the tail vein within 4 hours after TBI, and only the same amount of normal saline was transfused in CG group. After transplantation, the survival and weight changes of mice in each group were observed for 30 days, and the changes of blood routine were monitored regularly. Mice peripheral blood was collected 21 days after transplantation to detect the chimerism rate of the donor. Hematoxylin-eosin staining was performed on the skin, liver and colon of mice 21 days after transplantation to analyze the histopathological changes of aGVHD target organs. Results: All the mice in each group were successfully transplanted. After TBI, the weight and activity of mice in all groups decreased, and the phenomenon of bone marrow suppression appeared. During the observation period, all mice in CG group and SL group survived, 3 mice in SM group died with survival time of (26.0±5.8) days, and 6 mice in SH group died with survival time of (20.9±7.3) days. The body weight of mice in SH group was lower than that in CG group, SL group and SM group 21days after transplantation [(25.0±0.7), (25.5±0.4), (25.0±1.4) vs (20.8±0.8) g, all P<0.05]. Compared with CG group, SL group and SM group, the levels of leukocyte, erythrocyte, hemoglobin and platelet in SH group decreased 21 days after transplantation (all P<0.05). There was no significant difference in donor chimerism rate among SL group, SM group and SH group [(95.8%±0.8%), (95.5%±1.4%) and (95.1%±1.3%), respectively, all P>0.05]. Compared with CG group, SL group and SM group, the tissue structure of aGVHD target organs in SH group was severely damaged, with a large number of inflammatory cells infiltratedand higher histopathological scores than SL group and SM group (all P<0.05). Conclusion: For aging CB6F1 mice, after 6 Gy TBI pretreatment with linear accelerator X-ray, PBMC (1×107/each) and spleen cells (2.0×107/each) were injected to successfully induce aGVHD model after non-myelablative haplo-PSCT.

Quantum Phase Transition in a Quantum Ising Chain at Nonzero Temperatures.

We study the response of a thermal state of an Ising chain to a nonlocal non-Hermitian perturbation, which coalesces the topological Kramer-like degeneracy in the ferromagnetic phase. The dynamic responses for initial thermal states in different quantum phases are distinct. The final state always approaches its half component with a fixed parity in the ferromagnetic phase but remains almost unchanged in the paramagnetic phase. This indicates that the phase diagram at zero temperature is completely preserved at finite temperatures. Numerical simulations for Loschmidt echoes demonstrate such dynamical behaviors in finite-size systems. In addition, it provides a clear manifestation of the bulk-boundary correspondence at nonzero temperatures. This work presents an alternative approach to understanding the quantum phase transitions of quantum spin systems at nonzero temperatures.

[The multicenter study on the registration and follow-up of low anticoagulation therapy for the heart valve operation in China].

OBJECTIVE: To investigate the optimal anticoagulation methods and monitoring strategy for Chinese patients undergoing heart valve replacement, which is potentially quite different from western populations. METHODS: In this multicenter prospective cohort study, the anticoagulation and monitoring strategy data was acquired from 25 773 in-hospital patients in 35 medical centers and 20 519 patients in outpatient clinic in 11 medical centers from January 1st, 2011 to December 31th, 2015. RESULTS: As for in-hospital patients, mean age of study population was (48.6±11.2) years old; main etiology of valve pathology was rheumatic (87.5%) origin among study cohort; 94.8% of study population received mechanical valve implantation; international normalized ratio (INR) monitoring (in all the study centers) and low-intensity anticoagulation strategy (31 hospitals chose target INR range of 1.5-2.5, and actual values of INR among 89.2% of 100 069 in-hospital monitoring samples were 1.5-2.5), with mean actual INR values of 1.84±0.53, and warfarin dosage of (2.82±0.93) mg/d were widely adopted among the study centers; strategies of in-hospital warfarin administration were similar in all the study centers; complication rates of low-intensity anticoagulation strategy were low in severe hemorrhage (0.02%), thrombosis (0.05%), and thromboembolism (0.05%) events, without anticoagulation-related death.As for 18 974 outpatient clinic patients, the follow-up rate was 92.47%, with a total of 30 012 patient-years (Pty). Anticoagulation-related morbidity and mortality rates were 0.67% and 0.15% Pty; major hemorrhage morbidity and mortality rates were 0.25% and 0.13% Pty; thromboembolism morbidity and mortality rates were 0.45% and 0.03% Pty.The mean dosage of warfarin daily dosage was (2.85±1.23) mg/d and INR value was 1.82±0.57.No significant regional difference in the intensity of anticoagulation therapy was noted during the study. CONCLUSIONS: INR can be used as a normalized indicator for intensity of anticoagulation therapy in China.The optimal anticoagulation intensity with INR range from 1.5 to 2.5 is safe and effective for Chinese patients with heart valve replacement, and there is no significant regional difference in the intensity of anticoagulation therapy.

HLA-DRB1*11:106, a variant of HLA-DRB1*11, discovered in a Chinese bone marrow donor.

HLA-DRB1*11:106 has 1 nucleotide change from HLA-DRB1*11:01:01 at nucleotide 155 (G → A).

A new human leukocyte antigen class II allele, DRB1*09:12.

HLA-DRB1*09:12 allele differs from HLA-DRB1*09:01:02 by a single nucleotide substitution at codon 41 (AAG → AAC).

A novel HLA allele, HLA-B*55:50, was identified by sequence-based typing.

HLA-B*55:50 has one nucleotide change from HLA-B*55:02:01 where 169 R is changed to L.

Identification of a novel HLA allele, HLA-A*11:101, in a platelet donor from China.

HLA-A*11:101 has one nucleotide change from HLA-A*11:02:01 where 120 Q is changed to R.

Exploring Putative Causal Associations between Diet and Periodontal Disease Susceptibility.

INTRODUCTION: Dietary factors may play an important role in periodontal health. However, current evidence from observational studies remains inconclusive. OBJECTIVE: This study aimed to investigate the causal relationships between dietary exposures and periodontal disease risks using Mendelian randomization analysis. METHODS: Large-scale genome-wide association study summary statistics for 20 dietary factors were obtained from the MRC-IEU consortium. Multivariable and univariable 2-sample Mendelian randomization analyses were performed to assess the causal effects of each dietary exposure on 6 periodontal outcomes, including gingivitis and periodontitis. RESULTS: Genetically predicted higher dried fruit intake was significantly associated with reduced risks of acute gingivitis (odds ratio [OR]: 0.02; 95% confidence interval [CI]: 0.00-0.42; P = 0.01) and bleeding gums (OR: 0.96; 95% CI: 0.93-0.99; P = 0.01). Higher fresh fruit and water intake showed protective effects against chronic gingivitis (OR: 0.18; 95% CI: 0.04-0.91; P = 0.04 and OR: 0.15; 95% CI: 0.04-0.53; P = 0.00) and bleeding gums (OR: 0.95; 95% CI: 0.92-0.981; P = 0.00 and OR: 0.98; 95% CI: 0.96-0.99; P = 0.02). Alcohol intake frequency and processed meat intake were risk factors for bleeding gums (OR: 1.01; 95% CI: 1.00-1.02; P = 0.01 and OR: 1.05; 95% CI: 1.01-1.08; P = 0.00) and painful gums (OR: 1.01; 95% CI: 1.00-1.01; P = 0.00 and OR: 1.02; 95% CI: 1.01-1.03; P = 0.00). Most of the causal relationships between genetic predisposition to the specified dietary factors and periodontal diseases remained statistically significant (P < 0.05) after adjusting for genetic risks associated with dentures, smoking, and type 2 diabetes in multivariable Mendelian randomization models. CONCLUSIONS: The findings suggest potential protective effects of higher fruit and water intake against gingivitis and other periodontal problems, while alcohol and processed meat intake may increase the risks of periodontal disease. Our study provides preliminary causal evidence on the effects of diet on periodontal health and could inform prevention strategies targeting dietary habits to improve oral health. KNOWLEDGE TRANSFER STATEMENT: This study suggests that fruit and water intake may protect against periodontal disease, while alcohol and processed meats increase risk, informing dietary guidelines to improve oral health.

Sequencing of a novel HLA-DRB1*09:01:07 allele in a Chinese individual.

The novel DRB1*09:01:07 allele differs from DRB1*09:01:02 by only one nucleotide substitution in exon 2.

Detection of the new HLA-B*08:57 allele in a voluntary platelet donor.

HLA-B*08:57 has 1 nt change from HLA-B*08:01:01 at nt 108 where G→C (codon 36 ATG→ATC).

A novel HLA-B*40 allele, HLA-B*40:74, detected in a Chinese individual.

The HLA-B*40:74 allele has two nucleotide changes at positions 103 and 106 of exon 2 from the closest matching allele HLA-B*40:01:01.

Identification of a novel allele, HLA-B*37:04:02, from a registered donor of the China Marrow Donor Program.

B*37:04:02 has 1 nt change from B*37:04:01 at nt 618 where G→A (codon 206 GCG→GCA) resulting in no coding change.

Exceptional spectrum and dynamic magnetization.

A macroscopic effect can be induced by a local non-Hermitian term in a many-body system, when it manifests simultaneously level coalescence of a full real degeneracy spectrum, leading to exceptional spectrum. In this paper, we propose a family of systems that support such an intriguing property. It is generally consisted of two arbitrary identical Hermitian sub-lattices in association with unidirectional couplings between them. We show exactly that all single-particle eigenstates coalesce in pairs even only single unidirectional coupling appears. It means that all possible initial states obey the exceptional dynamics, resulting in some macroscopic phenomena, which never appears in a Hermitian system. As an application, we study the dynamic magnetization induced by complex fields in an itinerant electron system. It shows that an initial saturated ferromagnetic state at half-filling can be driven into its opposite state according to the dynamics of high-order exceptional point. Any Hermitian quench term cannot realize a steady opposite saturated ferromagnetic state. Numerical simulations for the dynamical processes of magnetization are performed for several representative situations, including lattice dimensions, global random and local impurity distributions. It shows that the dynamic magnetization processes exhibit universal behavior.

A new human leukocyte antigen-B allele, HLA-B*52:11.

A new HLA-B*52 allele differs from B*52:01:01 by a single nucleotide exchange at position 583 where a 'C' to 'T'.

Recapturing public health sciences for HIV/AIDS in China.

In recent years, human immunodeficiency virus (HIV) has spread from high-risk groups to the general population in China. Scientific interpretation of HIV figures, prevalence and proportion vs. incidence is displayed to correctly guide politicians and lay people in understanding the situation. Although behaviour-focused studies have been conducted in China, many have focused on 'scientific' issues, with limited attention given to human dimensions or contexts. An evidence-based public health approach, with strict evaluation in terms of cost-effectiveness and behavioural outcomes, needs to be developed, together with activity to encourage decentralization and community engagement of programmes. Policies and strategies on HIV prevention and control need to be mindful of Chinese culture and reality, including the expansion of screening and surveillance.

A quasi-experimental study on a community-based behaviour change programme among injecting drug users in Sichuan, China.

The objective of this study is to explore an effective model of comprehensive intervention on HIV/AIDS among injecting drug users (IDUs) in communities located in urban areas and to evaluate its feasibility in Sichuan Province, China. A quasi-experimental study was designed so that various intervention measures were conducted in the intervention city but not in the control city. A Behaviour Surveillance Survey was introduced to evaluate intervention exposure and the effect of behaviour change. In the intervention city, services received by IDUs increased over time (P < 0.001). Awareness of HIV increased from 34.2% in 2003 to 58.3% in 2004, and to 67.4% in 2005 (P < 0.001). The proportion of IDUs surveyed who shared a needle the last time they injected drugs decreased from 17.1% in 2003 to 7.0% in 2005, and in terms of the past month from 42.4% in 2003 to 18.4% in 2005 (P < 0.001). Data from a multivariate logistic regression analysis showed that comprehensive intervention was a protective factor for behaviour change (odds ratio [OR] =0.561; 95% confidence interval [CI], 0.424-0.741). A well-designed and organized comprehensive intervention programme will effectively change the high-risk behaviour among IDUs in these communities. A more comprehensive, expanded and integrated response is needed when conducting an HIV/AIDS prevention programme.

Synthesis and performance of colloidal silica nano-abrasives with controllable size for chemical mechanical planarization.

Under the analysis of particle growth mechanism, the monodisperse colloidal silica abrasives for chemical mechanical planarization (CMP) slurry were synthesized by the modified ion-exchanged and hydrothermal step-polymerization process. After the colloidal silica with controllable size was synthesized, its microstructure, stability and CMP performance was characterized and tested by SEM, HRTEM, Zeta potential Analyzer and CMP tester. Results show that the spherical, high stable (Zeta potential: -52.8 mV) colloidal silica with controllable size was achieved. About its CMP performance, the polishing rate for silicon double-side CMP is increased to be 317 nm/min and the polished surface roughness (RMS) was reduced to 0.32 nm.

Majorana flat band edge modes of topological gapless phase in 2D Kitaev square lattice.

We study a Kitaev model on a square lattice, which describes topologically trivial superconductor when gap opens, while supports topological gapless phase when gap closes. The degeneracy points are characterized by two vortices in momentum space, with opposite winding numbers. We show rigorously that the topological gapless phase always hosts a partial Majorana flat band edge modes in a ribbon geometry, although such a single band model has zero Chern number as a topologically trivial superconductor. The flat band disappears when the gapless phase becomes topologically trivial, associating with the mergence of two vortices. Numerical simulation indicates that the flat band is robust against the disorder.