Objective To explore the quality of life and its related factors among left‐behind children in Shandong and Si‐chuan provinces .Methods The cluster sampling method was used to select the study participants and thus each 3 rural primary schools were randomly chosen as the study sites in Shandong and Sichuan provinces .t‐test ,χ2 test and rank sum test were employed to perform univariate analysis ,and multivariate analysis was conducted using multiple linear regression .Results In this study ,there were totally 1804 participants with 778 left‐behind ones .There was statistical difference between left‐behind children and average children in each aspects of quality of life and the total score(P<0 .05) .Multiple linear regression analysis showed that the multiple influencing factors of the quality of life among left‐behind children in Shandong and Sichuan provinces were age ,the guardian、left‐behind time、parents′care and study result .Conclusion The quality of life among left‐behind children in Shandong and Sichuan provinces was not high and was affected by many factors .In order to improve the quality of life of left‐behind children ,the guardians should pay more attention to care and communicate with their children in the future education and management of left‐behind chil‐dren ,especially the elder ,long time left behind or poor grades ones .

Objective:To summarize and elucidate the impact of ambient air pollution on biological aging among middle-aged and older adults.Methods:"Air pollution""Biological age""Epigenetic age""Biological aging"and"Epigenetic aging", as well as specific names of air pollutants and biological age were used as search keywords. This study searched the databases of PubMed and Web of Science for eligible English articles and CNKI, CQVIP, Wanfang, CBM, CSTP and other Chinese databases for eligible Chinese articles from inception until June 30, 2023. The language was limited to Chinese and English.Results:Among the 14 included articles, five studies investigated the impact of air pollution on DNA methylation age using different algorithms, while six studies explored the relationship between air pollutants and telomere length. Six studies focused on frailty as an outcome, and an additional study revealed the relationship between fine particulate matter (PM 2.5) and its components with composite indicator age (KDM age). The results indicated that, although different forms of biological ages were susceptible to different ambient air pollutants at different degrees, previous studies had consistently found that the increased levels of PM 2.5 and one of its major components, black carbon (BC), could significantly accelerate the biological aging of middle-aged and older adults. Similar trends were observed with nitrogen oxides (NO x) and ozone (O 3) but with relatively limited evidence. Conclusion:Major air pollutants could accelerate the biological aging of middle-aged and older adults.

Objective:To summarize and elucidate the impact of ambient air pollution on biological aging among middle-aged and older adults.Methods:"Air pollution""Biological age""Epigenetic age""Biological aging"and"Epigenetic aging", as well as specific names of air pollutants and biological age were used as search keywords. This study searched the databases of PubMed and Web of Science for eligible English articles and CNKI, CQVIP, Wanfang, CBM, CSTP and other Chinese databases for eligible Chinese articles from inception until June 30, 2023. The language was limited to Chinese and English.Results:Among the 14 included articles, five studies investigated the impact of air pollution on DNA methylation age using different algorithms, while six studies explored the relationship between air pollutants and telomere length. Six studies focused on frailty as an outcome, and an additional study revealed the relationship between fine particulate matter (PM 2.5) and its components with composite indicator age (KDM age). The results indicated that, although different forms of biological ages were susceptible to different ambient air pollutants at different degrees, previous studies had consistently found that the increased levels of PM 2.5 and one of its major components, black carbon (BC), could significantly accelerate the biological aging of middle-aged and older adults. Similar trends were observed with nitrogen oxides (NO x) and ozone (O 3) but with relatively limited evidence. Conclusion:Major air pollutants could accelerate the biological aging of middle-aged and older adults.

Based on the unique syndrome characteristics of metabolic associated fatty liver disease （MAFLD） in Lingnan （岭南） area， this paper discussed the clinical experience of Huangqi （Radix Astragali） in the treatment of MAFLD in Lingnan area. It is summarized that spleen deficiency and yang weakness， and internal accumulation of damp-turbidity are the source of the disease， and at the early stage， Huangqi， commonly 15~30 g， could be used to fortify the spleen and warm the earth， thereby making the deficiency fire latent， as well as raise the clear and warm the exterior so as to inhibit damp-turbidity； medication needs to be progressively supplemented， and can be used together with Taizishen （Radix Pseudostellariae）， Baizhu （Rhizoma Atractylodis Macrocephalae）， Fuling （Poria）， and Fangfeng （Radix Saposhnikoviae） to back up the earth and inhibit dampness. Qi stagnation and blood constraint， yin dampness and heat accumulation are the pathogenesis of disease progression. Huangqi should be taken to invigorate the spleen and flourish the liver， unblock yang， and move stagnation. The dosage is often maintained at 30~60 g， to circulate the qi and unblock yang qi in the middle jiao （焦）， usually combined with Chaihu （Radix Bupleuri）， Baishao （Radix Paeoniae Alba） and Yujin （Radix Curcumae） integrating warm and cool medicinals. Stubborn turbid and fat condensing in the liver is a severe stage of the disease and may be concurrent with various pathogens such as dampness， phlegm， and heat， for which 60~90 g Huangqi should be used to invigorate blood and disperse fat， reinforce healthy qi and expel pathogens， often with medicinals that can disperse fat and direct the turbid downward such as Shanzha （Fructus Crataegi）， Juemingzi （Semen Cassiae）， Lulutong （Fructus Liquidambaris） and Zexie （Rhizoma Alismatis）. When prescribing， it is suggested to combine with other medicinals according to the season， thereby adjusting the ascending and descending of the property of Huangqi， thereby conforming to the nature of the four seasons.

The emergence of high virulent mutant strains of infectious bursal disease virus(IBDV)becomes a serious threat to the poultry industry.However,the live attenuated IBDV vaccine can potentially revert to a virulent strain.Therefore,it is a necessary to develop safe and effective IB-DV-associated vaccines.The construction of a recombinant Marek's disease(MD)vaccine strain,CVI988,expressing the IBDV VP2 protein,can protect against disease induced by both IBDV and Marek's disease virus(MDV).Here,the IBDV-VP2 gene was integrated into the UL55 locus of CVI988 by bacterial artificial chromosome(BAC)technique,resulting in the recombinant virus CVI988 BAC-VP2.The recombinant virus was characterized by PCR,IFA and subsequently the bi-ological properties of the recombinant virus were investigated.The results showed that the recom-binant virus CVI988 BAC-VP2 was successfully rescued.The VP2 protein stably expressed in chick-en embryo fibroblasts(CEF).The growth kinetics and plague size assays showed that there was comparable replication ability between recombinant virus and parental virus.This study provides the basis for the development of a low-cost vaccine against both IBDV and MDV infections.

Objective: To explore the expression levels of matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1) protein and the change of MMP-9/TIMP-1 ratio in wound exudates of patients with stages Ⅲ and Ⅳ pressure ulcers during wound healing. Methods: From July 2017 to July 2018, 30 patients with stage Ⅲ pressure ulcers [30 wounds, 16 males and 14 females, aged (65±10) years] and 34 patients with stage Ⅳ pressure ulcers [50 wounds, 17 males and 17 females, aged (65±9) years] admitted to Hebei General Hospital who met the inclusion criteria were enrolled in this prospective cohort study. According to the principle of wound treatment and the characteristics and needs of wound in different periods, individualized intervention measures were formulated for patients and appropriate dressings were selected. At the time of admission and on 7, 14, 21, 28 days of treatment, the healing of pressure ulcer wounds was evaluated by Pressure Ulcer Healing Scale. Afterwards, the wound exudate was collected at each time point to detect the expression levels of MMP-9 and TIMP-1 protein by enzyme-linked immunosorbent assay, and the MMP-9/TIMP-1 ratio was calculated. Data were processed with analysis of variance for repeated measurements of single group and linear trend test. Results: (1) There were significantly statistical differences in wound healing scores of patients with stages Ⅲ and Ⅳ pressure ulcers among the time of admission and on 7, 14, 21, 28 days of treatment within each stage (F=145.382, 153.234, P<0.01), and they all showed a gradually decreasing trend (F=170.466, 284.585, P<0.01). (2) At the time of admission and on 7, 14, 21, 28 days of treatment, the expression levels of MMP-9 protein in wound exudates of patients with stages Ⅲ and Ⅳ pressure ulcers were (171±104), (138±88), (110±70), (85±55), (62±41) ng/L and (193±107), (173±104), (139±83), (114±70), (89±56) ng/L, respectively. There were significantly statistical differences within each stage (F=58.007, 111.680, P<0.01), and they all showed a gradually decreasing trend (F=62.901, 134.628, P<0.01). At the time of admission and on 7, 14, 21, 28 days of treatment, the expression levels of TIMP-1 protein in wound exudates of patients with stages Ⅲ and Ⅳ pressure ulcers were (6.2±3.9), (5.6±3.4), (5.1±3.1), (4.4±2.5), (3.8±2.3) ng/L and (4.8±2.5), (4.7±2.6), (4.4±2.6), (4.6±2.7), (4.1±2.4) ng/L, respectively. There were significantly statistical differences within each stage (F=25.479, 7.778, P<0.01), and there was a gradually decreasing trend in stage Ⅲ (F=62.901, P<0.01) and a decreasing trend in stage Ⅳ (F=134.628, P<0.01). At the time of admission, the expression levels of MMP-9 and TIMP-1 in wound exudates of patients with stage Ⅲ pressure ulcers were similar to those of patients with stage Ⅳ pressure ulcers (t=-1.03, 1.47, P>0.05). (3) At the time of admission and on 7, 14, 21, 28 days of treatment, the MMP-9/TIMP-1 ratios in the wound exudates of patients with pressure ulcers of stages Ⅲ and Ⅳ were 30±13, 25±9, 22±9, 20±8, 17±6 and 43±19, 37±13, 32±10, 26±9, 22±9, respectively. There were significantly statistical differences within each stage (F=37.173, 97.191, P<0.01), and they all showed a gradually decreasing trend (F=54.183, 130.088, P<0.01). At the time of admission, the MMP-9/TIMP-1 ratio in wound exudates of patients with stage Ⅳ pressure ulcers was significantly higher than that of patients with stage Ⅲ pressure ulcers (t=-3.42, P<0.01). Conclusions During the wound healing process of patients with stages Ⅲ and Ⅳ pressure ulcers, the expression levels of MMP-9 and TIMP-1 protein and the MMP-9/TIMP-1 ratio in wound exudates show a decreasing trend. The stage of wound healing can be predicted according to the expression level of MMP-9 protein and the MMP-9/TIMP-1 ratio.

Chronic wounds are with characteristics of long last time and cannot heal in time, which is a problem in clinic. Wound pH value plays an important role in the process of healing of chronic wounds. In this paper, we review the relative researches on wound pH value and wound microenvironment, summarize the potential relationship between wound pH value and healing of chronic wounds, as well as the method to change pH value of chronic wounds, thereby to provide theoretical basis for the treatment of chronic wounds in clinic.

METTL3 and METTL14 are two components that form the core heterodimer of the main RNA m6A methyltransferase complex (MTC) that installs m6A. Surprisingly, depletion of METTL3 or METTL14 displayed distinct effects on stemness maintenance of mouse embryonic stem cell (mESC). While comparable global hypo-methylation in RNA m6A was observed in Mettl3 or Mettl14 knockout mESCs, respectively. Mettl14 knockout led to a globally decreased nascent RNA synthesis, whereas Mettl3 depletion resulted in transcription upregulation, suggesting that METTL14 might possess an m6A-independent role in gene regulation. We found that METTL14 colocalizes with the repressive H3K27me3 modification. Mechanistically, METTL14, but not METTL3, binds H3K27me3 and recruits KDM6B to induce H3K27me3 demethylation independent of METTL3. Depletion of METTL14 thus led to a global increase in H3K27me3 level along with a global gene suppression. The effects of METTL14 on regulation of H3K27me3 is essential for the transition from self-renewal to differentiation of mESCs. This work reveals a regulatory mechanism on heterochromatin by METTL14 in a manner distinct from METTL3 and independently of m6A, and critically impacts transcriptional regulation, stemness maintenance, and differentiation of mESCs.
Animals ; Mice ; Methylation ; Chromatin ; Histones/metabolism* ; RNA, Messenger/genetics* ; Methyltransferases/metabolism* ; RNA/metabolism*