Swertiamarin relieves radiation-induced intestinal injury by limiting DNA damage.

Radiotherapy is the conventional treatment for pelvic abdominal tumors. However, it can cause some damage to the small intestine and colorectal, which are very sensitive to radiation. Radiation-induced intestinal injury (RIII) affects the prognosis of radiotherapy, causing sequelae of loss of function and long-term damage to patients' quality of life. Swertiamarin is a glycoside that has been reported to prevent a variety of diseases including but not limited to diabetes, hypertension, atherosclerosis, arthritis, malaria, and abdominal ulcers. However, its therapeutic effect and mechanism of action on RIII have not been established. We investigated whether swertiamarin has a protective effect against RIII. In this article, we use irradiator to create cellular and mouse models of radiation damage. Preventive administration of swertiamarin could reduce ROS and superoxide anion levels to mitigate the cellular damage caused by radiation. Swertiamarin also attenuated RIII in mice, as evidenced by longer survival, less weight loss and more complete intestinal barrier. We also found an increase in the relative abundance of primary bile acids in irradiated mice, which was reduced by both FXR agonists and swertiamarin, and a reduction in downstream interferon and inflammatory factors via the cGAS-STING pathway to reduce radiation-induced damage.

Uncovering the anti-biofilm activity of Ilicicolin B against Staphylococcus aureus.

The formation of bacterial biofilms reduces the entry of antibiotics into bacteria and helps bacteria tolerate otherwise lethal concentrations of antimicrobials, leading to antibiotic resistance. Therefore, clearing bacterial biofilm is an effective strategy to tackle drug resistance. Currently, there are no approved antibiotics for inhibiting bacterial biofilm formation. We found that Ilicicolin B had excellent antibacterial activity against MRSA without obvious hemolytic activity. More importantly, Ilicicolin B effectively inhibited the biofilm formation in a concentration-dependent manner by crystal violet colorimetric assay and fluorescence microscopy analysis. Exposure of Staphylococcus aureus to Ilicicolin B for 24 h reduced the protein and polysaccharide components in EPS, suggesting that Ilicicolin B disintegrated the biofilms by dissociating the EPS in a matrix. In addition, Ilicicolin B demonstrated strong antibacterial effects in a murine abscess model of S. aureus. Our findings suggest that Ilicicolin B has the potential to treat S. aureus infection by inhibiting biofilm formation.

Fan beam CT-guided online adaptive external radiotherapy of uterine cervical cancer: a dosimetric evaluation.

PURPOSE: To discuss the dosimetric advantages and reliability of the accurate delivery of online adaptive radiotherapy(online ART) for uterine cervical cancer(UCC). METHODS AND MATERIALS: Six UCC patients were enrolled in this study. 95% of the planning target volume (PTV) reached 100% of the prescription dose (50.4 Gy/28fractions/6weeks) was required. The patients were scanned with uRT-Linac 506c KV-FBCT then the target volume (TV) and organs at risk (OARs) were delineated by doctors. The dosimeters designed and obtained a routine plan (Plan0). KV-FBCT was used for image guidance before subsequent fractional treatment. The online ART was processed after registration, which acquired a virtual nonadaptive radiotherapy plan (VPlan) and an adaptive plan (APlan). VPlan was the direct calculation of Plan0 on the fractional image, while APlan required adaptive optimization and calculation. In vivo dose monitoring and three-dimensional dose reconstruction were required during the implementation of APlan. RESULTS: The inter-fractional volumes of the bladder and rectum changed greatly among the treatments. These changes influenced the primary gross tumor volume (GTVp) and the position deviation of GTVp and PTV and positively affected the prescription dose coverage of TV. GTVp decreased gradually along with dose accumulation. The Dmax, D98, D95, D50, and D2 of APlan were superior to those of VPlan in target dose distribution. APlan had good conformal index, homogeneity index and target coverage. The rectum V40 and Dmax, bladder V40, the small bowel V40 and Dmax of APlan were better than that of VPlan. The APlan's fractional mean γ passing rate was significantly higher than the international standard and the mean γ passing rate of all cases after the three-dimensional reconstruction was higher than 97.0%. CONCLUSION: Online ART in external radiotherapy of UCC significantly improved the dose distribution and can become an ideal technology to achieve individualized precise radiotherapy.

Tiotropium in Patients with Bronchiectasis: A Prospective Cohort Study.

PURPOSE: There are limited studies on the use of bronchodilators for the treatment of bronchiectasis. This study investigated the efficacy of tiotropium in patients with bronchiectasis and airflow limitation. METHODS: This study was a prospective cohort study, including 169 patients with bronchiectasis and airflow limitation from 2015 to 2019. The clinical outcomes observed in our study were the effect of tiotropium on the frequency of moderate exacerbations, the time to the first severe exacerbation, and the annual decline in FEV1. RESULTS: After 12 months, the annual decline in the FEV1 after bronchodilator use was 27.08 ml or 42.9 ml per year in the group with or without tiotropium, respectively. Treatment with tiotropium was associated with a decreased risk of moderate exacerbation of bronchiectasis (Adjusted RR 0.618 95% CI 0.493-0.774; P < 0.005). The time to the first severe acute exacerbation of bronchiectasis in the tiotropium group was longer than the non-tiotropium group (Adjusted HR 0.333 95% CI 0.219-0.506; P < 0.001). CONCLUSION: In conclusion, prospective cohort study showed that tiotropium effectively ameliorated the annual decline in the FEV1, with a lower-risk rate of moderate exacerbations and prolonging the time to the first-time severe exacerbation in patients with bronchiectasis and airflow limitation.

Oropharyngeal administration of colostrum targeting gut microbiota and metabolites in very preterm infants: protocol for a multicenter randomized controlled trial.

BACKGROUND: Oropharyngeal administration of colostrum (OAC) has an immune-stimulating effect on oropharyngeal-associated lymphoid tissue, and can promote the maturation of the gastrointestinal tract. However, how OAC promotes intestinal maturation in preterm infants by altering gut microbiota remains unclear. We aim to assess changes in gut microbiota and metabolites after OAC in very preterm infants. METHODS: A multicenter, double-blind, randomized controlled trial will be conducted in three large neonatal intensive care units in Shenzhen, China, with preterm infants with gestational age less than 32 weeks at birth and birth weight less than 1500 g. It is estimated that 320 preterm infants will be enrolled in this study within one year. The intervention group will receive oropharyngeal administration of 0.2 ml colostrum every 3 h, starting between the first 48 to 72 h and continued for 5 consecutive days. Following a similar administration scheme, the control group will receive oropharyngeal administration of sterile water. Stool samples will be collected at the first defecation, as well as on the 7th, 14th, 21st and 28th days after birth for analysis of effect of OAC on gut microbiota and metabolites through 16sRNA gene sequencing and liquid chromatography-mass spectrometry. DISCUSSION: This proposal advocates for the promotion of OAC as a safe and relatively beneficial protocol in neonatal intensive care units, which may contribute to the establishment of a dominant intestinal flora. Findings of this study may help improve the health outcomes of preterm infants by establishment of targeted gut microbiota in future studies. TRIAL REGISTRATION: NCT05481866 (registered July 30, 2022 on ClinicalTrials.gov).

The relationship between glycosylated hemoglobin level and red blood cell storage lesion in blood donors.

BACKGROUND: Glycosylated hemoglobin (HbA1c), not routinely screened in blood donors, is associated with morphological, biochemical, and functional abnormalities of red blood cells (RBCs) and with enhanced oxidative stress. We aimed to explore HbA1c levels in blood donors and their effect on RBC storage. STUDY DESIGN AND METHODS: An analytical cross-sectional study was conducted on 875 eligible blood donors aged 18-60 years from May 1, 2021, to August 30, 2021. Two selected groups of donors (HbA1c <6.5%, n = 10; HbA1c ≥ 6.5%, n = 10) exhibiting as similar as possible baseline values (such as age, sex, and living habits, etc.) were recruited for blood donation in leukoreduced CPDA-1 units. RBC morphological, biochemical, structural, and oxidative stress states were measured during 5-35 days of storage. RESULTS: Elevated HbA1c prevalence was 37%, including 31.7% (277/875) in the prediabetes range (HbA1c 5.7%-6.4%) and 5.4% (47/875) in the diabetes range (HbA1c ≥ 6.5%). Age, body mass index (BMI), smoking, and alcohol consumption were the main factors influencing the HbA1c levels. During storage, high-HbA1c group had abnormal RBC morphology, impaired membrane function, and ion imbalance (higher mean corpuscular volume, distribution width, hemolysis rate, potassium ion efflux, and phosphatidylserine exposure) as compared with low HbA1c group. Additionally, RBC oxidative stress was significantly increased in donors with high HbA1c levels during 21-35 days. DISCUSSION: Blood donors proportion with abnormal HbA1c levels was relatively high, and donor HbA1c levels may be associated with stored RBCs capacity. Our study provides new insights into the different effects of donor HbA1c levels on RBC storage lesions.

Comparisons of care practices for very preterm infants and their short-term outcomes in two tertiary centers in northwest and south China: A retrospective cohort study.

BACKGROUND: Care practices for very preterm infants and the mortality and morbidity of the infants vary widely among countries and regions with different levels of economic development, including the different areas in China. We aimed to compare the obstetric and delivery room practices of two representative tertiary newborn centers in the northwestern and southern regions of China and the mortality and morbidity of their very preterm infants. METHODS: A retrospective cohort study was conducted. Very preterm infants born between 220/7 and 316/7 weeks of gestation, and admitted to Qinghai Red Cross Hospital (QHH) and Shenzhen Baoan Women's and Children's Hospital (SZH) from January 1, 2018 to December 31, 2020, were included. The infants' characteristics and short-term outcomes, and the hospitals' care practices were compared between the two cohorts. RESULTS: Three hundred and two infants in QHH and 505 infants in SZH were enrolled, and the QHH cohort was more mature than the SZH cohort was (gestational age 30.14 (29.14-31.14) vs. 29.86 (27.86-31.00 weeks, respectively), p < 0.001). Fewer antenatal steroids and more tracheal intubations were used in QHH than in SZH [(73.8% vs. 90.9%, p < 0.001) and (68.2% vs. 35.0%, p < 0.001, respectively)]. The odds of mortality [aOR = 10.31, 95%CI: (6.04, 17.61)], mortality or major morbidity [aOR = 5.95, 95%CI: (4.05, 8.74)], mortality despite active treatment [aOR = 3.14, 95%CI: (1.31, 7.53)], mortality or major morbidity despite active treatment [aOR = 3.35, 95%CI: (2.17, 5.17)], moderate or severe bronchopulmonary dysplasia [aOR = 3.66, 95%CI: (2.20, 6.06)], and severe retinopathy of prematurity [aOR = 3.24, 95%CI: (1.19, 8.83)] were higher in the QHH cohort. No significant difference in the rate of severe neurological injury or necrotizing enterocolitis ≥ Stage 2 was found between the cohorts. CONCLUSION: Obstetric and delivery room care practices used in the management of very preterm infants differed considerably between the QHH and SZH cohorts. Very preterm infants born in QHH have higher odds of mortality or severe morbidity compared with those born in SZH.

Evaluation and countermeasures of contracted services of Chinese family doctors from demanders' point of view - a case study of a city.

BACKGROUND: The "gatekeepers" for residents' health are their family doctors. The implementation of contracted services provided by family doctors is conducive to promoting hierarchical diagnosis and treatment and achieving the objective of providing residents comprehensive and full-cycle health services. Since its implementation in 2016, the contract service system for Chinese family doctors has yielded a number of results while also highlighting a number of issues that require further investigation. Consequently, the purpose of this study is to assess the impact of family doctors' contracted services in a Chinese city from the perspective of demanders (i.e., contracted residents), identify the weak links, and then propose optimization strategies. METHODS: In this study, a city in Shandong Province, China was selected as the sample city. In January 2020, 1098 contracted residents (including 40.5% men and 59.5% women) from 18 primary medical institutions (including township health centers and community health centers) were selected for on-site investigation. Take the PCAT-AS(Adult Short) scale revised in Chinese as the research tool to understand the medical experience of contracted residents in primary medical institutions, and interview some family doctors and residents to obtain more in-depth information. RESULTS: Among the four core dimensions of PCAT-AS, the score of Continuous was the highest (3.44 ± 0.58); The score of Coordinated was the lowest (3.08 ± 0.66); Among the three derived dimensions, the score of Family-centeredness was the highest (3.33 ± 0.65); The score of Culturally-competent was the lowest (2.93 ± 0.77). The types of contracting institutions, residents' age, marital status, occupation, and whether chronic diseases are confirmed are the influencing factors of PCAT scores. CONCLUSION: The family doctors' contracted services in the city has achieved certain results. At the same time, there are still some problems, such as difficult access to outpatient services during non-working hours, incomplete service items, an imperfect referral system, and inadequate utilization of traditional Chinese medicine services, it is recommended that the government continue to enhance and increase its investment in relevant policies and funds. Primary medical institutions should improve the compensation mechanism for family doctors and increase their work enthusiasm, improve and effectively implement the two-way referral system, gradually form an orderly hierarchical pattern of medical treatment, provide diversified health services in accordance with their own service capacity and the actual needs of residents, and improve the utilization rate of traditional Chinese medicine services in primary medical institutions.

Alarmone Ap4A is elevated by aminoglycoside antibiotics and enhances their bactericidal activity.

Second messenger molecules play important roles in the responses to various stimuli that can determine a cell's fate under stress conditions. Here, we report that lethal concentrations of aminoglycoside antibiotics result in the production of a dinucleotide alarmone metabolite-diadenosine tetraphosphate (Ap4A), which promotes bacterial cell killing by this class of antibiotics. We show that the treatment of Escherichia coli with lethal concentrations of kanamycin (Kan) dramatically increases the production of Ap4A. This elevation of Ap4A is dependent on the production of a hydroxyl radical and involves the induction of the Ap4A synthetase lysyl-tRNA synthetase (LysU). Ectopic alteration of intracellular Ap4A concentration via the elimination of the Ap4A phosphatase diadenosine tetraphosphatase (ApaH) and the overexpression of LysU causes over a 5,000-fold increase in bacterial killing by aminoglycosides. This increased susceptibility to aminoglycosides correlates with bacterial membrane disruption. Our findings provide a role for the alarmone Ap4A and suggest that blocking Ap4A degradation or increasing its synthesis might constitute an approach to enhance aminoglycoside killing potency by broadening their therapeutic index and thereby allowing lower nontoxic dosages of these antibiotics to be used in the treatment of multidrug-resistant infections.

Structural origin of hardness decrease in irradiated sodium borosilicate glass.

Mechanical properties such as hardness and modulus of sodium borosilicate (NBS) glasses in irradiation conditions were studied extensively in recent years. With irradiation of heavy ions, a trend that the hardness of NBS glasses decreased and then stabilized with increase of dose has been reported. Variations in network structures were suggested for the decrease of hardness after irradiation. However, details of these variations in a network of glass are not clear yet. In this paper, molecular dynamics was applied to simulate the network variations in a type of NBS glass and the changes in hardness after xenon irradiation. The simulation results indicated that hardness variation decreased with fluence in an exponential law, which was consistent with experimental results. The origin of hardness decrease after irradiation might be attributed to the break of Biv-O links that could be derived from the (1) decrease of average coordinate number of boron, (2) decrease of Si-O-Biv bonds, and (3) increase of non-bridging oxygen.

Dynamic analysis of phospholipid metabolism of mouse macrophages treated with common non-steroidal anti-inflammatory drugs.

Through studying the changes of the total phospholipid components in mouse macrophages under the inflammatory status and the drug intervention status, we found the targets of non-steroidal anti-inflammatory drugs on phospholipids, thus providing the basis for the targets of in vitro anti-inflammatory effects of non-steroidal anti-inflammatory drugs. After RAW264.7 cells were pretreated with common non-steroidal anti-inflammatory drugs (aspirin and ibuprofen) and, respectively, stimulated with KLA for various periods (0.5, 4, 12, 16, and 24 h), the phospholipids were extracted. The dynamic changes of phospholipids in cells under various stimulations were analyzed with UPLC-Q-TOF-MS technique. Through the statistical analysis of Simca-P, we explored the potential targets of non-steroidal anti-inflammatory drugs on phospholipids. Through the dynamic analysis of phospholipids, we found two biomarkers (PC(17:1/18:1), PA(18:0/18:4)) which might be in vitro intervention inflammatory response targets of non-steroidal anti-inflammatory drugs. The analysis results show that in anti-inflammatory effects, non-steroidal anti-inflammatory drugs can inhibit COX, induce the cellular fatty acid desaturation and the changes of phospholipid components, stimulate free fatty acids, activate calcium ion channels of endoplasmic reticulum, and promote cell endocytosis, thus controlling inflammation and activating cells. Non-steroidal anti-inflammatory drugs can promote endocytosis, alter cell inflammatory response, and activate the process cells, thus realizing the anti-inflammatory effects.

Radical 1,2-aryl migration in α,α-diaryl allylic alcohols toward ß-silyl ketones.

A copper-catalyzed radical 1,2-aryl migration in α,α-diaryl allylic alcohols is developed, leading to ß-silyl carbonyl compounds in moderate to good yields. The migration of aryls with lower aromaticity is favored. This procedure features the employment of silanes as commercially available materials.

The N-silylation of sulfoximines.

The copper-catalyzed N-silylation of sulfoximines was achieved in the presence of di-tert-butyl peroxide. Notably, alkyl, phenyl and alkoxyl silanes were all suitable reaction partners. Mechanistic studies revealed that N-silyl acetamide serves as the intermediate.

Rhodium-catalyzed annulation between 2-arylimidazo[1,2-a]pyridines and alkynes leading to pyrido[1,2-a]benzimidazole derivatives.

A rhodium-catalyzed annulation between 2-arylimidazo[1,2-a]pyridines and alkynes was developed, leading to pyrido[1,2-a]benzimidazole derivatives in moderate to excellent yields. Notably, the ring C in pyrido[1,2-a]benzimidazole and the naphthalene framework were constructed consecutively, which provided a potential pathway leading to such a structure. This procedure tolerated chloro, bromo, cyano and methoxycarbonyl groups.

Di-tert-butyl peroxide-promoted α-alkylation of α-amino carbonyl compounds by simple alkanes.

A di-tert butyl peroxide (DTBP)-promoted α-alkylation of α-amino carbonyl compounds by simple alkanes is developed, proceeding through dual sp(3) C-H bonds cleavage. The reaction was applicable for α-amino ketones and α-amino esters, providing a facile pathway for the α-functionalization of these substrates. The radical pathway is involved in this transformation.

Study on the evaluation and influencing factors of contracted residents on the coordination of primary medical institutions.

Background: The implementation of family doctor contract service is a pivotal measure to enhance primary medical services and execute the hierarchical diagnosis and treatment system. Achieving service coordination among various institutions is both a fundamental objective and a central element of contract services. Objective: The study aims to assess residents' evaluations and determining factors related to the coordination of health services within primary medical institutions across different regions of Shandong Province. The findings intend to serve as a reference for enhancing the coordination services offered by these institutions. Methods: The study employed a multi-stage stratified random sampling method to select three prefecture-level cities in Shandong Province with different economic levels. Within each city, three counties (districts) were randomly sampled using the same method. Within each county (district), three community health service centers and township health centers implementing family doctor contract services were selected randomly. Face-to-face questionnaire surveys were conducted with contracted residents using the coordination dimension of the revised Primary Care Assessment Tools Scale (PCAT) developed by the research team. Data analysis was conducted using such methods as one-way analysis of variance and multiple linear regression. Results: The sample included 3,859 contracted residents. The coordination dimension score of primary medical institutions averaged 3.41 ± 0.18, with the referral service sub-dimension scoring 3.60 ± 0.58 and the information system sub-dimension scoring 3.34 ± 0.65. The overall score of the referral service sub-dimension surpassed that of the information system sub-dimension. Regression results indicated that the city's economic status, the type of contracted institutions, gender, education, marital status, income, occupation, health status, and endowment insurance payment status significantly influenced the coordinated service score of primary medical institutions (p < 0.05). Conclusion: The coordination of primary medical institutions in Shandong Province warrants further optimization. Continued efforts should focus on refining the referral system, expediting information infrastructure development, enhancing the service standards of primary medical institutions, and fostering resident trust. These measures aim to advance the implementation of the hierarchical diagnosis and treatment and two-way referral system.

Discovery of novel Thymol-TPP antibiotics that eradicate MRSA persisters.

The high prevalence of methicillin-resistant Staphylococcus aureus (MRSA) strains and the formation of non-growing, dormant "persisters" subsets help bacteria evade antibiotic treatment and enhance bacterial resistance, which poses a serious threat to human life and health. It is urgent to discover novel antibacterial therapies effective against MRSA persisters. Thymol is a common nutraceutical with weak antibacterial and antitumor activities. A series of Thymol triphenylphosphine (TPP) conjugates (TPP-Thy3) was designed and synthesized. These compounds showed significantly improved inhibitory activity against Gram-positive bacteria compared with Thymol. Among them, Thy3d displayed a low probability of resistance selection and showed excellent biocompatibility. Interestingly, Thy3d elicited a rapid killing effect of MRSA persisters (99.999%) at high concentration. Fluorescence experiments, electron microscopy, molecular dynamics simulation and bilayer experiment confirmed that Thy3d conjugates exerted potent antimicrobial activity by disrupting the integrity of the membrane of bacterial even the persister. Furthermore, Thy3d exhibited considerable efficacy in a mouse model of subcutaneous murine MRSA infection. In summary, TPP-Thy3 conjugates are a series of novel antibacterial agents and could serve as a new therapeutic strategy for combating antibiotic resistance.

Short-term prognosis of very-preterm infants of ethnic minorities and Han nationality at high altitude: a single-center, retrospective study.

OBJECTIVE: We aimed to analyze the perinatal care of very-preterm infants (VPIs) in plateau areas of China and to explore any differences in short-term outcomes between ethnic minorities and Han nationality. METHODS: VPIs with gestational age (GA) <32 weeks admitted to Qinghai Red Cross Hospital from 1 January 2018 to 31 December 2020 were enrolled. Maternal information, neonatal information, perinatal care and discharge outcomes were retrospectively collected and analyzed. RESULTS: A total of 302 VPIs were examined, including 143 (47.4%) ethnic minority infants and 159 (52.6%) Han infants. Mothers of ethnic minority infants were significantly younger than those of Han infants (27 y vs. 30 y, p < .001). There were no differences in the incidence of assisted reproduction, multiple pregnancies, maternal hypertension, clinical chorioamnionitis or premature rupture of membranes >18 h between ethnic minority mothers and Han mothers. Lower proportions of cesarean section and incidence of maternal diabetes were observed in ethnic minority mothers than in Han mothers [(9.1 vs.17.6%, p < .05) and (42.7 vs. 57.9%, p < .05, respectively)]. Meanwhile, fewer antenatal steroids were used in minority group than Han group (65.7 vs. 81.1%, p < .05). No significant differences in rates of death, active treatment, necrotizing enterocolitis stage ≥2, moderate-to-severe BPD, and incidence of severe retinopathy of prematurity in VPIs were found between the two groups and in all GA subgroups. Severe neurological injury was significantly less common in the minority newborns than in the Han infants (1.2 vs. 6.1%, p < .05). Compared with Han group, no excess risk of death, death or major morbidity, death despite active treatment, death or major morbidity despite active treatment was observed in ethnic minorities, with or without adjusting for gestational age and prenatal steroids. CONCLUSIONS: Short-term prognosis of VPIs of ethnic minorities were similar to those of Han nationality.

Higher ETCOc predicts longer phototherapy treatment in neonatal hyperbilirubinemia.

Objective: This study aimed to evaluate the predictive performance of end-tidal carbon monoxide corrected to ambient carbon monoxide (ETCOc) values phototherapy in neonates with significant hyperbilirubinemia. Methods: A prospective study was conducted on neonates with significant hyperbilirubinemia who received phototherapy between 3 and 7 days of life. The breath ETCOc and serum total bilirubin of the recruited infants were measured on admission. Results: The mean ETCOc at admission in 103 neonates with significant hyperbilirubinemia was 1.70 ppm. The neonates were categorized into two groups: phototherapy duration ≤72 h (n = 87) and >72 h (n = 16) groups. Infants who received phototherapy for >72 h had significantly higher ETCOc (2.45 vs. 1.60, P = 0.001). The cutoff value of ETCOc on admission for predicting longer phototherapy duration was 2.4 ppm, with a sensitivity of 62.5% and specificity of 88.5%, yielding a 50% positive predictive value and a 92.7% negative predictive value. Conclusion: ETCOc on admission can help predict the duration of phototherapy in neonates with hyperbilirubinemia, facilitate clinicians to judge disease severity, and make clinical communication easier and more efficient.

Prevalence of High-Altitude Polycythemia and Hyperuricemia and Risk Factors for Hyperuricemia in High-Altitude Immigrants.

Song Zhen, Anxin Zhang, Jie Luo, Guanghai Xiong, Haibo Peng, Rang Zhou, Yuanfeng Li, Hongqiang Xu, Zhen Li, Wei Zhao, and Haoxiang Zhang. Prevalence of high-altitude polycythemia and hyperuricemia and risk factors for hyperuricemia in high-altitude immigrants. High Alt Med Biol. 24:132-138, 2023. Background: Few studies have investigated the epidemiology of chronic mountain sickness (CMS) in high-altitude immigrants. This study evaluated the prevalence of polycythemia and hyperuricemia (HUA) and risk factors for HUA in high-altitude immigrants. Methods: A cross-sectional study was conducted with 7,070 immigrants 15-45 years of age living on the Tibetan Plateau between January and December 2021. Information from routine physical examinations was obtained from each participant. Binary logistic regression analysis was performed to determine the correlation of several risk factors for HUA. Results: The prevalence of high-altitude polycythemia (HAPC) and HUA was 25.8% (28.7% in males and 9.4% in females) and 54.2% (59.9% in males and 22.5% in females), respectively. The highest prevalence of HAPC in males and females was observed in participants 26-30 and 21-25 years of age, respectively. The highest prevalence of HUA in both males and females was observed in participants 26-30 years of age. Binary logistic regression analysis showed that age, sex, and hemoglobin (Hb) concentration were risk factors for HUA, among which age was a negative factor and male sex and Hb concentration were positive factors. Conclusions: Immigrants are more susceptible to HAPC and HUA. The high prevalence of CMS of immigrants may be associated with Hb concentration, age, and sex.