Background In 2021, chronic obstructive pulmonary disease (COPD) emerged as the forth leading cause of death in the world. However, the impact of air pollutants on COPD is still inconsistent across current studies. Objective To analyze the relationship between ambient sulfur dioxide (SO₂) exposure and hospital admissions for COPD in Lanzhou, and to examine the modified effects of SO₂ across different genders, age groups, and seasons. Methods A total of 20718 hospital admission records for COPD were collected from Lanzhou between 2016 and 2020, alongside synchronized data on SO₂ concentration and meteorological variables. A generalized additive model integrated with a distributed lag nonlinear model was used to assess the relationship and the lag effects between SO₂ exposure and COPD admissions. Potential confounders, including meteorological factors, day-of-the-week effect, and holidays, were controlled for, with a maximum lag period set at 7 d. Two-pollutant models and sensitivity analyses were conducted to ensure robustness. Results are expressed as relative risks (RR) with 95% confidence intervals (95%CI). Results During the study period, the average daily number of COPD admissions was 11.34±7.03. The average mass concentration of SO₂ was (23.72±12.35) μg·m⁻³. SO₂ exposure was positively correlated with COPD admissions; specifically, each 10 μg·m⁻³ increase in SO₂ concentration was associated with an RR of 1.440 (95%CI: 1.317, 1.573). Stratified analyses found that at a cumulative lag of 7 d, the RRs were higher among females, individuals aged ≥65 years, and during the cold season. Conversely, no significant increase in COPD admission risk related to SO₂ was observed during the warm season. For every 10 μg·m⁻³ increase in SO₂ concentration, the RR was 1.483 (95%CI: 1.311, 1.678) for females, 1.441 (95%CI: 1.311, 1.583) for those aged > 65 years， and 1.595 (95%CI: 1.313, 1.937) during the cold season. Conclusion Short-term exposure to ambient SO₂ exposure in Lanzhou is associated with an increased risk of COPD admission. The association is more pronounced among females, the elderly (aged> 65 years) and during the cold season.

Objective To explore the differences in terahertz(THz)signal characteristics between normal and ischemic liver tissues of New Zealand rabbits using THz time-domain spectroscopy(THz-TDS),thereby providing a novel detection technique for the pathological detection of liver tissues.Methods Liver ischemia models were established in New Zealand rabbits.The THz scanning signal maps of normal and ischemic liver tissues were obtained using a reflective THz-TDS system,and the acquired signals were subjected to principal component analysis.Results Both normal and ischemic liver tissues displayed two distinct peaks in their THz signals.However,the amplitude of the THz signal in ischemic liver tissue was higher than that in normal liver tissue,with significant differences also observed in their signal morphologies.Principal component analysis results revealed a clear clustered distribution between the signals of normal and ischemic liver tissues,indicating that THz-TDS could effectively distinguish between the two tissue types.Conclusion THz-TDS can be applied to the detection of ischemic liver tissue,providing experimental evidence to support further research on the early diagnosis of liver ischemia and exhibiting broad prospects for clinical application.

OBJECTIVE To analyze the chemical constituents of Heihuang Chizhu Granules and the blood composition of rats af-ter administration by UPLC-Q-TOF-MS/MS.METHODS A Waters ACQUITY UPLC HSS T3 column(3 mm×100 mm,1.8 μm)was eluted with acetonitrile-0.1%formic acid as mobile phase,and the data were collected in electrospray ion source positive and neg-ative ion mode and then identified with the reference retention time,precise molecular weight,secondary fragment ions,and references to relevant literature.RESULTS A total of 104 chemical components were identified from Heihuang Chizhu Granules,including 26 flavonoids,24 organic acids,14 triterpenoids,8 terpenoids,7 phenylpropanoids,11 monoglycosides,and 14 other components(phe-nols,alkaloids,etc.).On this basis,39 blood-entering components were identified in the plasma of rats administered via gavage,in-cluding 28 prototypes and 11 metabolites.CONCLUSION The chemical constituents of Heihuang Chizhu Granules and the compo-nents entering the blood of rats are analyzed and identified for the first time in this study,and the results provide a scientific basis for the basic research of Heihuang Chizhu Granules and the establishment of process quality control standards.

Objective To explore the difference in terahertz signal characteristics between rat skin scar and normal skin using terahertz time-domain spectroscopy technology,thereby providing a novel non-invasive detection technique for the pathological examination of skin scars.Methods A rat model of whole-layer skin defect was prepared,and a reflectance terahertz time-domain spectroscopy system was used to obtain the terahertz signal maps of normal skin and scarred area.Results The terahertz signals of normal skin showed two obvious reflection time-domain signal peaks,and the characteristics of the reflection peaks at different reflection points were relatively regular.The terahertz signals of skin scar also had two obvious reflection time-domain signal peaks,but the highest peak was lower than that of normal skin.In addition,principal component analysis revealed that skin scar signals and normal skin signals were clustered together separately.The terahertz signal at different sites differed significantly(P<0.05).Conclusion Terahertz time-domain spectroscopy technology can be applied to the non-invasive detection of skin scarring,exhibiting a good application prospect in biomedicine.

Objective To explore the differences in terahertz(THz)signal characteristics between normal and ischemic liver tissues of New Zealand rabbits using THz time-domain spectroscopy(THz-TDS),thereby providing a novel detection technique for the pathological detection of liver tissues.Methods Liver ischemia models were established in New Zealand rabbits.The THz scanning signal maps of normal and ischemic liver tissues were obtained using a reflective THz-TDS system,and the acquired signals were subjected to principal component analysis.Results Both normal and ischemic liver tissues displayed two distinct peaks in their THz signals.However,the amplitude of the THz signal in ischemic liver tissue was higher than that in normal liver tissue,with significant differences also observed in their signal morphologies.Principal component analysis results revealed a clear clustered distribution between the signals of normal and ischemic liver tissues,indicating that THz-TDS could effectively distinguish between the two tissue types.Conclusion THz-TDS can be applied to the detection of ischemic liver tissue,providing experimental evidence to support further research on the early diagnosis of liver ischemia and exhibiting broad prospects for clinical application.

Objective:To establish a rapid and precise dose measurement method with EBT4 film and ensure its measurement accuracy to be within the required range through strict operational procedures for the purpose of addressing the two essential issues of poor measurement accuracy and timeliness of EBT film under FLASH conditions.Methods:After storing under different humidity conditions for a certain period of time, the film was exposed to radiation for analyzing the influence of air humidity on the intrinsic performance of EBT film. By means of repeated scanning operations and the film angle rotation, the influences of repeated scanning and film placement angle were analuzed. Parabolic correction method was used to reduce the spatial position influence during the scanning process. By analying the relationship between net optical density (netOD) and absorbed dose through the comparison of three fitting method, the optimal fitting curve was selected. After irradiation of the same batch of films for 5 min and 24 h, the film doses were calibrated and then compared with ionization chamber-measured result. The rapid and precise film dosimetry method was used to measure both the percentage depth dose from X-rays at ultra-high dose rate and the dose distribution at a depth of 2 cm in water.Results:Air humidity had the greatest influence on the intrinsic performance of EBT film (approximately 20%). The average deviation of repeated scans is within 0.5%. The angle at which the film is placed significantly affected the readouts of the film with the maximum influence approximately 70%. The net optical density combined with polynomial fitting can control the fitting residuals of 1-16 Gy within 3%. The change rate of light channels at 5 min already mostly met the requirements of the rapid mode (< 0.5%). Compared with the measurement result obtained using the reference ionization chamber, the deviations of the 5 min or 24 h dose calibration curves were all within 2%.Conclusions:The EBT4 film can be employed as a precise dosimeter to quickly measure the FLASH radiation dose. Rapid and precise FLASH dose measurements can meet the stringent requirements of both preclinical and clinical FLASH research.

Objective To construct a uricase-deficient mouse model with stable inheritance using the CRISPR/Cas9 system,and evaluate its ability to simulate the disease characteristics of patients with hyperuricemia.Methods Double single guide RNAs(sgRNAs)were designed on both sides of exon 2～4 of the Uox gene.sgRNA and Cas9 mRNA for gene knockout were microinjected into the fertilized eggs of mice.After culture for 2～4 h,the embryos were transferred to surrogate mother mice to produce an F0 generation.Uox-knockout mice were identified by polymerase chain reaction and sequencing analysis.Positive mice were then mated with wild-type(WT)mice to produce an F1 generation,and heterozygous female and male F1 mice were then selected to obtain homozygous F2 mice.Serum and urine levels of uric acid,creatinine,and urea,and serum alanine aminotransferase(ALT)and aspartate aminotransferase(AST)levels were detected and compared between homozygous and wild-type mice.Pathological changes in kidney and liver tissues were observed by hematoxylin and eosin and Masson staining.Results Urine levels of serum uric acid(male:(4116.8±1928.1)μmol/L,P＜0.001;female:(2998.0±547.7)μmol/L,P＜0.01)and serum levels of uric acid(male:(478.4±114.6)μmol/L,P＜0.001;female:(507.7±129.6)μmol/L,P＜0.001),creatinine((91.8±55.6)μmol/L,P＜0.001),urea((28.6±13.9)mmol/L,P＜0.05),ALT((53.3±23.3)U/L,P＜0.01),and AST((203.3±70.3)U/L,P＜0.001)were significantly increased in Uox-/-mice compared with WT mice.Histopathological examination showed moderate hepatocyte degeneration in the liver,moderate-to-severe tubular cystic dilation,degeneration,and fibrosis in the kidney,glomerular hypertrophy and hyperplasia,small-vessel dilation and congestion,and infiltration of stromal monocytes and lymphocytes in Uox-/-mice.Conclusions We successfully established a homozygous uricase-deficient mouse strain using CRISPR/Cas9 technology,as a suitable animal model for research in the field of hyperuricemia.

Genetic factors are often involved in the pathogenesis of young adult stroke, and its subtype, atherosclerotic type of large arteries, may be caused by a combination of genetic and environmental factors, but little is known about its underlying pathogenesis. To provide clues for better understanding of identifying relevant stroke etiological genetic factors and adopting effective preventive strategies, the role of genetic factors in atherosclerosis and related risk factors was described, and the possible genetic mechanisms of large-artery atherosclerotic stroke in young people were explored, which may be further investigated in future research in the following areas: etiological typing of stroke in young people and the related genetic mechanisms; modifiable vascular risk factors and the development of secondary prevention strategies; high-resolution vascular imaging magnetic resonance imaging in the etiological typing of stroke in young people and the pathogenesis of premature atherosclerosis and vulnerable plaques.

Approximately 30%-40% of epilepsy patients do not respond well to adequate anti-seizure medications (ASMs), a condition known as pharmacoresistant epilepsy. The management of pharmacoresistant epilepsy remains an intractable issue in the clinic. Its early prediction is important for prevention and diagnosis. However, it still lacks effective predictors and approaches. Here, a classical model of pharmacoresistant temporal lobe epilepsy (TLE) was established to screen pharmacoresistant and pharmaco-responsive individuals by applying phenytoin to amygdaloid-kindled rats. Ictal electroencephalograms (EEGs) recorded before phenytoin treatment were analyzed. Based on ictal EEGs from pharmacoresistant and pharmaco-responsive rats, a convolutional neural network predictive model was constructed to predict pharmacoresistance, and achieved 78% prediction accuracy. We further found the ictal EEGs from pharmacoresistant rats have a lower gamma-band power, which was verified in seizure EEGs from pharmacoresistant TLE patients. Prospectively, therapies targeting the subiculum in those predicted as "pharmacoresistant" individual rats significantly reduced the subsequent occurrence of pharmacoresistance. These results demonstrate a new methodology to predict whether TLE individuals become resistant to ASMs in a classic pharmacoresistant TLE model. This may be of translational importance for the precise management of pharmacoresistant TLE.
Epilepsy, Temporal Lobe/diagnosis* ; Animals ; Drug Resistant Epilepsy/drug therapy* ; Electroencephalography/methods* ; Rats ; Anticonvulsants/pharmacology* ; Neural Networks, Computer ; Male ; Humans ; Phenytoin/pharmacology* ; Adult ; Disease Models, Animal ; Female ; Rats, Sprague-Dawley ; Young Adult ; Convolutional Neural Networks

Objective:To establish a rapid and precise dose measurement method with EBT4 film and ensure its measurement accuracy to be within the required range through strict operational procedures for the purpose of addressing the two essential issues of poor measurement accuracy and timeliness of EBT film under FLASH conditions.Methods:After storing under different humidity conditions for a certain period of time, the film was exposed to radiation for analyzing the influence of air humidity on the intrinsic performance of EBT film. By means of repeated scanning operations and the film angle rotation, the influences of repeated scanning and film placement angle were analuzed. Parabolic correction method was used to reduce the spatial position influence during the scanning process. By analying the relationship between net optical density (netOD) and absorbed dose through the comparison of three fitting method, the optimal fitting curve was selected. After irradiation of the same batch of films for 5 min and 24 h, the film doses were calibrated and then compared with ionization chamber-measured result. The rapid and precise film dosimetry method was used to measure both the percentage depth dose from X-rays at ultra-high dose rate and the dose distribution at a depth of 2 cm in water.Results:Air humidity had the greatest influence on the intrinsic performance of EBT film (approximately 20%). The average deviation of repeated scans is within 0.5%. The angle at which the film is placed significantly affected the readouts of the film with the maximum influence approximately 70%. The net optical density combined with polynomial fitting can control the fitting residuals of 1-16 Gy within 3%. The change rate of light channels at 5 min already mostly met the requirements of the rapid mode (< 0.5%). Compared with the measurement result obtained using the reference ionization chamber, the deviations of the 5 min or 24 h dose calibration curves were all within 2%.Conclusions:The EBT4 film can be employed as a precise dosimeter to quickly measure the FLASH radiation dose. Rapid and precise FLASH dose measurements can meet the stringent requirements of both preclinical and clinical FLASH research.