Glioma is the most common primary intracranial tumor. Despite surgical resection, radiation therapy, chemotherapy, and Tumor Treating Fields, the median survival period is still less than 21 months. In recent years, immunotherapy for glioma has become a research hotspot. The immune microenvironment of glioma plays an important role in immune escape, which is an important means of malignant progression. Exploring the immune escape mechanism of glioma, understanding the progress of immunotherapy, and extending the survival period of patients with glioma as much as possible are the major challenges facing glioma treatment. Therefore, this article reviews the new understanding of the immune system in the central nervous system, immune cells and immune escape in glioma, and immunotherapy for glioma, to help further understand the mechanism of glioma development and provide new ideas for immunotherapy.

Objective:To explore the normal ranges of perfusion parameters between cerebral hemisphere, cerebellar hemisphere and brain anatomical subregions (56 pairs) in different gender and age groups with multiple post labeling delay time (Multi-PLD) arterial spin labeling (ASL) imaging.Methods:From November 2020 to December 2020, 42 healthy adult volunteers (Male 25, Female 17) were recruited to perform 7 PLD ASL imaging, including 21 young adults (15 males and 6 females, aged 23—35 years) and 21 seniors (10 males and 11 females, aged 36—74 years). The data was processed offline by Cereflow software to obtain arterial arrival time (ATT) and corrected cerebral blood flow (CBF) and cerebral blood volume (CBV) perfusion parameters. SimpleITK standardization function was used to standardize the calculated perfusion image according to the anatomical automatic labeling (AAL) template. Therefore, CBF, ATT, CBV perfusion values of brain subregions were obtained. Paired samples t test, Wilcoxon rank sum test, independent samples t test and Mann-Whitney U test were used to compare the differences of perfusion parameters in the cerebral hemisphere, the cerebellar hemisphere, brain subregions depending on side, gender and age. Pearson correlation analysis was used to compare the correlations of perfusion parameters with age. Results:CBF in 62.5% (35/56) subregions and CBV in 44.6% (25/56) subregions were higher in right side than those in left side. ATT in most brain anatomical subregions (16/56) were higher in left side. The CBF [(35.30±8.31) vs. (34.34±7.53) ml·100g -1·min -1, P=0.021], CBV [(0.47±0.11) vs. (0.45±0.09) ml/100g, P<0.001], ATT [(1.30±0.10) vs. (1.24±0.11) s, P<0.001] in left cerebellar hemisphere were higher than that of right side. The CBF (28/56) of cerebral hemisphere, cerebellar hemisphere and brain subregions was higher in females than that in males, while ATT in 83.9% (47/56) subregions was lower than that in males (all P<0.05). CBV in female subjects was higher only in 5 brain regions (superior occipital gyrus, middle occipital gyrus, inferior occipital gyrus, superior parietal gyrus and cerebelum_7b) (all P<0.05). In young subjects, CBF in 44.6% (25/56) subregions and CBV in 33.9% (19/56) subregions were higher than those in the senior group (all P<0.05). The ATT in most subregions in young group were lower than those in senior group, but the difference was statistically significant only in rectus gyrus ( P=0.026) and paracentral lobule ( P=0.006). The CBF ( r=-0.430, P=0.005) and CBV ( r=-0.327, P=0.035) of cerebral hemisphere were negatively correlated with age. The CBF (24/25, r range:-0.497 —-0.343, all P<0.05) and CBV (16/19, r range:-0.474 —-0.322, all P<0.05) in most subregions were negatively correlated with age, while ATT was positively correlated (gyrus rectus: r=0.311, P=0.045; paracentral lobule: r=0.392, P=0.010). Conclusions:Multi-PLD ASL imaging could be applied for quantitative analysis of brain perfusion. The perfusion parameters of anatomical subregions are different depending on side, gender, and age.

Objective: The aim was to investigate the genotype distribution of two major epitopes of large surface protein (PreS1) of hepatitis B in Chinese patients and to explore the association between the genotypes of these two epitopes, and to determine whether PreS1 full-length genotype could be revealed according to the polypeptide sequence of key epitopes. Methods: HBV DNA was extracted from the serum of patients for PCR amplification. 278 samples amplified successfully were sequenced and compared with the known HBV sequences in Genbank to determine the two key epitopes of HBV PreS1 genotype (amino acid epitope 21-47 and 94-117, abbreviated as P21 and P94) and PreS1 full-length genotypes. The correlation among three genotyping approaches was analyzed by Cohen’s kappa coefficient to verify the consistency between the key-epitope genotyping and the full-length preS1 genotyping. Results: 232 samples were successfully sequenced. The genotyping based on the kind of P21 epitope protein sequence, 201 cases for genotype C, 23 cases for genotype B and 8 cases for uncertain genotypes and genotyping based on the form of P94 epitope protein sequence, 199 cases for genotype C, 25 cases for genotype B and 8 cases for indeterminate genotypes. Lastly, the genotyping based on sequence of the full-length PreS1 sequence, 207 and 25 cases for genotype C and B. P21 or P94 epitope genotyping and PreS1 full length genotyping were highly consistent, respectively, 96.55% and 96.12%, and the two epitopes (P21and P94) genotyping have parallel consistency (93.10%). Conclusion In this study, an innovatively genotyping method based on the amino acid sequence of key epitopes was proposed. The genotypes of HBV in china were mainly B and C genotypes, and the genotypes of key conserved epitopes of HBV PreS1 were highly consistent with the full-length genotyping ( > 96%). Moreover, genotyping with one or two key epitopes can be used in place of the full-length genotyping.

BACKGROUND: Asthma imposes a large healthcare burden in China and the United States (US). However, the trends of asthma mortality and the relative risk factors have not been comparatively analyzed between the countries. The aim of this study was to compare the mortality and risk factors between China and the US. METHODS: The deaths, and mortality rates of asthma in China and the US during 1990-2019 were obtained from the Global Burden of Disease Study 2019. The age-period-cohort model was used to estimate these mortality rates based on a log-linear scale with additive age, period, and cohort effects. The population attributable fractions of risk factors for asthma were estimated. RESULTS: In 1990-2019, the asthma mortality rate was higher in China than in the US. The crude and age-standardized asthma mortality rates trended downward in both China and the US from 1990 to 2019. The decline in mortality was more obvious in China. Mortality gap between the two countries was narrowing. A sex difference in asthma mortality was observed with higher mortality in males in China and females in the US. The age effects showed that mortality increased with age in adults older than 20 years, particularly in the elderly. Downward trends were generally observed in the period and cohort rate ratios in both countries, with China experiencing a more obvious decrease. Smoking and high body mass index (BMI) were the leading risk factors for asthma mortality in China and the US, respectively. Mortality attributable to occupational asthmagens and smoking decreased the most in China and the US, respectively. CONCLUSIONS In 1990-2019, the asthma mortality rate was higher in China than in the US; however, the mortality gap has narrowed. Mortality increased with age in adults. The improvements in asthma death risk with period and birth cohort were more obvious in China than in the US. Smoking, high BMI, and aging are major health problems associated with asthma control. The role of occupational asthmagens in asthma mortality underscores the importance of management and prevention of occupational asthma.
Adult ; Humans ; Male ; Female ; United States/epidemiology* ; Aged ; Young Adult ; Asthma/epidemiology* ; Risk Factors ; Smoking ; China/epidemiology*

In recent years, due to precise control of the amorphous mineral precursor in the demineralization of dentine collagen fibers in orderly deposition, forming apatite crystals similar to the natural mineralized dentin, the bottom-up remineralization approach which does not depend on the existence of seed crystallites, dentin biomimetic mineralization techniques gradually become a hotspot in the research field of restoration of demineralized dentin caused by dental caries. This paper reviews the changing concepts and practices of the remineralization of demineralized dentin, emphasizing biomimetic remineralization studies. The results of the literature review show that the traditional dentin remineralization method is usually a disordered mixture of demineralized dentin and minerals, so mineralized dentin is not comparable to natural mineralized dentin in terms of the morphological characteristics and mechanical properties. With its gradual increase in recent years, dentine biomimetic mineralization technology perfectly resembles the minerals in the dentin overlapping sequence arranged with the dentine collagen fiber structure characteristics, leading to greatly improved microstructural, physical and chemical properties. As a result, dentine biomimetic mineralization technology is expected to achieve new breakthroughs in the fields of resin-dentin bonding mixing layers and the decay of dentin. At present, the technical obstacles that need to be overcome in the clinical application of the biomimetic remineralization of dentin are how to continuously supplement all the active ingredients needed for mineralization in the process of remineralization and how to keep the mechanical properties of the parent material unchanged while slowly releasing all ingredients. Researchers have successively proposed three-step transportation of the biomimetic remineralization of raw materials, as well as the preparation of mineralization precursors stabilized by polymers in advance and the reuse of mesoporous silicon nanomaterials for the transportation of the mineralized ingredient system. The concept described above provides the preliminary in vitro experimental basis for the transformation of the biomimetic remineralization strategy of dentin in clinical applications.