BACKGROUND:As the high proliferation and low apoptosis of the bone marrow in polycythemia vera patients, hematopoietic stem cels transplanted into NOD/SCID mice can differentiate into erythroid cels, but whether hematopoietic stem cels transplantation could improve the hematopoietic function of aplastic anemia mice is not yet reported. OBJECTIVE:To investigate whether transplantation of bone marrow mononuclear cels with JAK2V617F mutation from polycythemia vera patients can influence hematopoietic reconstruction in aplastic anemia mice. METHODS:Severe aplastic anemia mouse models were established by using recombinant human interferon-γplus busulfan, and then, these mouse models were randomly divided into experimental group (n=10) and control group (n=10). Bone marrow mononuclear cels isolated from polycythemia vera patients with positive JAK2V617F mutation were transplanted into the mice in the experimental group via tail vein at 5 days after drug withdrawal.The same volume of normal saline was administered to the control group. Routine peripheral blood test, morphology of bone marrow cels, bone marrow biopsy, and percentage of CD45+ cels in the peripheral blood and marrow were determined at 14 days after transplantation. RESULTS AND CONCLUSION: At 14 days after transplantation, pancytopenia occurred in the experimental group, bone marrow smears showed scattered lymphocytes and hematopoietic progenitors, and bone marrow biopsy presented that hematopoietic tissues were reduced and a smal amount of granulocyte cels and erythroblasts could be seen, but megakaryocytes were rare. In contrast to the control group, there was no improvement in the hematopoietic function of mice in the experimental group. CD45+ cels were detectable in the peripheral blood and bone marrow in the experimental group, but not in the control group; and a higher percentage of CD45+ cels was measured in the bone marrow than in the peripheral blood of experimental group mice. Experimental findings indicate that bone marrow mononuclear cels from polycythemia vera patients with positive JAK2V617F mutation can be engrafted into aplastic anemia mice, but cannot improve the hematopoietic function of mice.

Objective To establish a county-level trauma treatment model,designed to prioritize efficiency and guided by a multidisciplinary approach for emergency green channels.Methods Adhering to the Consensus of Experts on the Construc-tion and Management of Trauma Centers in Municipal Comprehensive Hospitals(2020),and using the trauma center creation plan from Guangdong Province as a reference,we established a county-level trauma center,leveraging its strengths and unique at-tributes,with the emergency department as its core.Results The application of information technology facilitated the establish-ment of a two-way referral information platform and a three-tiered diagnosis and treatment system for county medical communities,thereby enhancing the efficiency and quality of healthcare.The implementation of the emergency green channel multidisciplinary treatment team model significantly improved the admission rates for complex and critical cases and increased the utilization of new technologies.Conclusion The development of a county-level emergency treatment system,spearheaded by the establishment of a provincial-level trauma center and a multidisciplinary team model for emergency green channels,can expedite trauma patient care,augment diagnostic efficiency and treatment efficacy,and catalyze advancements in medical technology within county hospitals.

Objective:To investigate personal exposures to nitrogen oxides(NOX)and nitrogen di-oxide(NO2)and the influence of baseline personal characteristics,living environment and daily activity patterns of the participants on the exposures among adults over 35 in Tianjin and Shanghai.Methods:In this panel study,91 healthy nonsmoking adults aged over 35 from Tianjin and Shanghai participated in our study.The study was conducted in summer and winter.The participants were followed for three times with an interval of at least two weeks.Only participants in Shanghai were followed once in winter because of the COVID-19 pandemic.Twenty-seven participants completed follow-up visits in both seasons.We measured their 24 h personal exposures to NOX and NO2and collected their baseline and time-activity in-formation through questionnaire/diary.The linear mixed model was used to analyze the associations be-tween potential influencing factors and personal NOX and NO2 exposure levels.Results:There were 349 follow-up visits with valid 24 h personal NO2 and NOX exposure measurements in the two cities.The ave-rage 24 h personal exposures to NO2 and NOX(volume fraction)in Tianjin participants were 18.0 x 10-9 and 26.2 × 10-9 in summer,and 31.0 x 10-9 and 54.9 x 10-9in winter,respectively;and the average 24 h personal exposures to NO2 and NOX in Shanghai participants were 38.7 x 10-9and 100.0x10-9in summer,and 45.5 x10-9 and 139.2 x 10-9 in winter,respectively.The results of univariate regression analysis showed that their personal NOX exposure levels were significantly associated with city,season,gender,average daily cooking times,and ambient NO2 concentrations measured at fixed-site monitoring stations.In addition to the above factors,the personal NOX exposure levels were also significantly associ-ated with educational level and the personal NO2 exposure levels were also significantly associated with passive smoking,average daily home time,cooking energy type,residential distance from main traffic road,and use of kitchen ventilators.Multivariate regression analysis showed that the personal exposure levels of NO2 and NOX were significantly lower in Tianjin than that in Shanghai,were significantly lower in summer than that in winter,and were significantly and positively associated with ambient NO2 concen-trations measured at fixed-site monitoring stations.In addition,personal NOX exposure levels were signifi-cantly lower in females than in males,and personal NO2 exposure levels were significantly positively asso-ciated with average daily cooking times and significantly inversely associated with average daily home time.For every interquartile range(IQR)increase(12.7 × 10-9)in ambient NO2,the personal NO2 exposure levels increased by 27.5％(95％CI:17.0％-38.9％),and personal NOX exposure levels in-creased by 16.1％(95％CI:7.1％-25.8％).Conclusion:Season,city and ambient NO2 concentra-tions are significant influencing factors of personal exposure levels of NO2and NOX At the same time,the personal exposures levels of NO2 are also affected by lifestyle factors.Our study provides scientific evi-dence for making precise air pollution control decisions and reducing the exposure levels of NOX in the population.