Ferroptosis is a key driver of the onset and progression of chronic obstructive pulmonary disease （COPD）. By exploring the role of ferroptosis in COPD from the perspective of "qi deficiency with retention and stagnation"， it is considered that mitochondrial dysfunction and imbalanced antioxidant defenses are the microscopic manifestations of "qi deficiency"， whereas iron accumulation and lipid peroxide deposition constitute the pathological basis of "retention and stagnation". In traditional Chinese medicine （TCM）， the treatment principle is tonifying deficiency and benefiting qi， scattering retention and unblocking stagnation. Its mechanism involves improving the antioxidant system and mitochondrial function to enhance cellular resistance to ferroptosis， as well as relieving pulmonary iron overload， excessive lipid peroxidation， and inflammatory factor release to reduce the accumulation of pathological products， thereby exerting therapeutic effects on COPD.

Objective:To investigate the completion rate of tumor evaluation at initial assessment and after neoadjuvant therapy for mid and low rectal cancer patients in the national multicenter real-world database.Methods:The prospective real-world study was conducted. The clinicopathological data of 1 074 patients who underwent surgical treatment for mid and low rectal cancer in 47 national medical institutions, including Peking Union Medical College Hospital et al, from May 12,2023 to May 11,2024 were collected. Observation indicators: (1) clinical characteristics of patients with mid and low rectal cancer; (2) initial colonoscopy and pathologic evaluation of tumors in patients with mid and low rectal cancer; (3) initial imaging evaluation of patients with mid and low rectal cancer; (4) imaging evaluation after neoadjuvant therapy for patients with mid and low rectal cancer. Measurement data with normal distribution were represented as Mean± SD, and measurement data with skewed distribution were represented as M( Q1, Q3). Count data were described as absoluter numbers and/or percentages. Results:(1) Clinical characteristics of patients with mid and low rectal cancer. Of the 1 074 patients, there were 713 males and 361 females, aged 63(56,70)years. The body mass index of 1 074 patients was 24(21,26)kg/m 2.For American Society of Anesthesiologists classification, there were 147 cases of stage Ⅰ, 641 cases of stage Ⅱ, 157 cases of stage Ⅲ, 2 cases of stage Ⅳ, and there were 127 cases missing data. (2) Initial colonoscopy and pathologic evaluation of tumors in patients with mid and low rectal cancer. Of the 1 074 patients, there were 787 cases (73.28%) undergoing complete colonoscopy, and there were only 197 cases (18.34%) undergoing immunohistochemical evaluation of all four mismatch repair proteins. (3) Initial imaging evaluation of patients with mid and low rectal cancer. Of the 1 074 patients, there were 842(78.40%) patients completing magnetic resonance imaging (MRI) or ultrasound evaluation, and there were 914(85.10%) patients completing chest, abdomen, and pelvis enhanced computed tomography (CT) evaluation. In the 149 patients completing rectal ultrasound evaluation, there were 122 cases (81.88%) comple-ting T staging evaluation, and there were 81 cases (54.36%) completing N staging evaluation. In the 808 patients completing rectal MRI evaluation, there were 708 cases (87.62%) completing T staging evaluation, and there were 590 cases (73.02%) completing N staging evaluation. (4) Imaging evalua-tion after neoadjuvant therapy for patients with mid and low rectal cancer. Of the 388 patients with neoadjuvant therapy, there were 332 patients (85.57%) completing MRI or ultrasound evaluation, and there were 327 patients (84.28%) completing chest, abdomen, and pelvis enhanced CT evalua-tion. In the 70 patients completing rectal ultrasound evaluation, there were 65 cases (92.86%) com-pleting T staging evaluation, and there were 49 cases (70.00%) completing N staging evaluation. In the 327 patients completing rectal MRI evaluation, there were 246 cases (75.23%) completing T staging, and there were 228 cases (69.72%) completing N staging evaluation. Conclusion:The com-pletion rate of tumor imaging evaluation at initial assessment and after neoadjuvant therapy for mid and low rectal cancer patients on a national scale is relatively good.

Objective:To investigate the differences in acute intestinal injury and regulatory mechanisms in mice following carbon ion FLASH radiotherapy (FLASH-RT) and conventional dose rate radiotherapy (CONV-RT).Methods:Healthy C57BL/6J mice were randomly divided into three groups: control group, FLASH-RT group (100 Gy/s), and CONV-RT group (0.1 Gy/s), with 9 mice in each group. All mice received carbon ion whole abdominal radiotherapy. DNA double-strand breaks (DSB) and cell proliferation were evaluated by measuring the expression of phosphorylated histone H2AX (γ-H2AX) and nuclear-associated antigen 67 (Ki67) using immunohistochemistry; apoptosis was analyzed using terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL); transcriptome sequencing was used to analyze the differences in molecular pathways between FLASH-RT and CONV-RT.Results:Compared with the CONV-RT group, the FLASH-RT group showed significantly reduced intestinal γ-H2AX signal at 3 h after radiotherapy ( t=3.80, P<0.01), significantly increased expression of Ki67 at the base of intestinal crypts at 6 h after radiotherapy ( t=4.30, P<0.001), and a significantly decreased number of TUNEL-positive cells at 12 h after radiotherapy ( t=3.08, P<0.01). Transcriptome sequencing analysis showed that FLASH-RT specifically activated the insulin-like growth factor (IGF) pathway, avoiding the excessive activation of CONV-RT-induced nuclear factor-κB and B cell receptor inflammatory pathways as well as the inhibition of energy metabolism. Conclusions:Compared with CONV-RT, carbon ion FLASH-RT can reduce DSB damage, preserve the proliferative activity of intestinal stem cells, activate the IGF pathway, and regulate inflammatory, immune, and metabolic pathways, thereby significantly alleviating acute intestinal epithelial injury. Specifically, the regulation of repair pathways mediated by reduced DSB and the inhibition of inflammatory pathways are potential protective mechanisms for normal tissues.

FLASH irradiation (FLASH-IR) is one of the cutting-edge research directions in the field of tumor radiotherapy. Previous studies have demonstrated that FLASH-IR can effectively eradicate tumors while significantly reducing damage to normal tissues, exhibiting unique biological effects characterized by high efficiency and low toxicity. Monte Carlo simulation at the microscopic scale is a critical method for studying radiobiological effects and has been widely applied in conventional radiotherapy research. In recent years, its application in microscopic reaction analysis and mechanistic exploration of FLASH-IR has grown rapidly. This article systematically reviews the latest advances and key challenges in microscopic Monte Carlo simulation studies of FLASH-IR, aiming to provide theoretical insights and method ological guidance for future research.

Objective:To analyze the effects of fluorine exposure on calcium ion metabolism and the expression of related calcium-regulating proteins in the kidneys of rats.Methods:Forty-five 5-week-old specific pathogen-free male Wistar rats (weighed 90 - 120 g) were selected and divided into three groups according to the randomized numeric table: 0 (control), 50, and 100 mg/L fluorine exposure groups, with 15 rats in each group. The control group was given deionized water, while the 50 and 100 mg/L fluorine exposure groups were given sodium fluoride solutions containing 50 and 100 mg/L fluorine ions, respectively. After 12 weeks, urine samples were collected, and kidneys and blood were harvested. Urinary fluorine levels were measured using a fluoride ion-selective electrode method. Calcium ion levels in the urine, kidneys, and serum were determinated using the methylthymol blue microplate method. The protein expression levels of transient receptor potential vanilloid receptor 5 (TRPV5), calbindin-D28K (CB-D28K), sodium-calcium exchanger-1 (NCX1), Klotho and plasma membrane calcium ATPase 1b (PMCA1b) in the kidneys were detected by Western blotting and immunohistochemistry.Results:The urinary fluorine levels in the control group and the 50 and 100 mg/L fluorine exposure groups were (0.48 ± 0.09), (20.01 ± 1.68), (37.45 ± 2.45) mg/L, respectively, with statistically significant differences between the groups ( F = 929.58, P < 0.001). Significant differences in calcium ion levels in urine, kidneys, and serum were observed among the three groups ( F = 14.66, 11.09, 10.31, P < 0.05). Compared with the control group, the 100 mg/L fluorine exposure group exhibited higher levels of calcium ion in the urine and kidneys, and lower serum calcium ion levels ( P < 0.05). The results of Western blotting analysis revealed that the protein expression levels of TRPV5 and CB-D28K in the kidneys increased with the increase of fluorine exposure level ( Z = 2.11, 2.11, P = 0.035). The protein expression level of NCX1 in the kidneys showed a decreasing trend with increasing fluorine exposure level ( Z = - 2.11, P = 0.035). Significant differences were also observed in the protein expression levels of Klotho and PMCA1b among the three groups ( F = 8.93, 7.08, P < 0.05). Compared with the control group, the 100 mg/L fluorine exposure group showed higher level of Klotho protein expression and lower level of PMCA1b protein expression in the kidneys ( P < 0.05). Immunohistochemical results indicated significant differences in the protein expression levels of TRPV5, CB-D28K, NCX1, and Klotho in the kidneys of the three groups ( F = 27.56, 24.94, 16.05, 32.72, P < 0.05). Compared with the control group, the protein expression levels of TRPV5, CB-D28K, and Klotho in kidneys of 50 and 100 mg/L fluorine exposure groups were higher, while the protein expression levels of NCX1 were lower ( P < 0.05). Conclusion:Fluorine exposure may cause calcium ion metabolism disorders by regulating the expression levels of Klotho and other calcium-regulating proteins in the kidneys.

Objective:To investigate the influencing factors of adult dental fluorosis in drinking water-borne endemic fluorosis areas of Inner Mongolia Autonomous Region.Methods:A case-control study was conducted in January 2024 to select adult fluorosis patients (case group) and healthy individuals (control group) from the drinking water-borne endemic fluorosis areas in Helinger County, Hohhot City, Inner Mongolia Autonomous Region as the survey subjects. Urine samples were collected to determine urinary fluoride concentration. A questionnaire survey was conducted. SPSS 25.0 software was used for χ 2 test and multivariate logistic regression analysis. Restricted cubic spline (RCS) was used to analyze the association between urinary fluoride concentration and the risk of dental fluorosis in adults. Results:A total of 161 individuals were included in the survey, including 100 in the case group and 61 in the control group. The results of univariate analysis showed that there were statistically significant differences in the distribution of gender, smoking, and urinary fluoride concentration between the case group and the control group (χ 2 = 7.54, 5.02, 9.69, P < 0.05). The results of multivariate logistic regression analysis indicated that gender ( OR = 0.36, 95% CI: 0.18 - 0.73, P = 0.005) and urinary fluoride concentration ( OR = 3.08, 95% CI: 1.46 - 6.67, P = 0.003) were the influencing factors of adult fluorosis. RCS analysis showed a significant linear dose-response relationship between the risk of dental fluorosis and urinary fluoride concentration ( Poverall trend = 0.001, Pnonlinear = 0.071). When the urinary fluoride concentration was greater than 1.57 mg/L, the risk of dental fluorosis increased with the increase of urinary fluoride concentration. Conclusion:Gender and urinary fluoride concentration are the risk factors of dental fluorosis in adults in drinking water-borne endemic fluorosis areas of Inner Mongolia Autonomous Region.

Objective To explore the clinical effect of applying an improved"outside-in"technique in hip arthroscopic surgery.Methods Totally 136 patients undergoing hip arthroscopic surgery between June 2021 and July 2023 were selected and studied retrospectively.According to their different surgi-cal approach,they were divided into a modified approach group(n=75,including 30 males and 45 fe-males,with an average age of 36±14)and a classic approach group(n=61,including 33 males and 28 females,with an average age of 31±11).Before as well as 4 weeks,3 months and 6 months after the surgery,both groups were evaluated using the visual analog scale(VAS)and Harris hip score,and observed their surgical complications.Moreover,the surgical outcomes and time of sur-gical approach establishment were compared between the two groups.Results There was no significant difference between the two groups in general information,preoperative VAS and Harris scores.More-over,no significant difference was found between the two groups in the Harris score after surgery.Compared with the classic approach group,the improved group had significantly less surgical time(49.0±16.9 min vs.66.0±13.3 min,P<0.05),without using the C-arm fluoroscopy during surgery.Moreover,in the modified approach group,the time for establishing the mid-anteriorapproach was sig-nificantly shortened(10.4±5.9 min vs.25.9±15.1 min,P<0.05),along with the traction time during surgery(66.0±13.3 min vs.49.0±16.9 min,P<0.05).Conclusion The modified"outside-in"hip ar-throscopy technique is a safe and effective surgical method,easier to operate,with shorter surgical time.

OBJECTIVE To analyze the ethanol extracts,total phenols,total flavonoids contents and HPLC fingerprints of typi-cal propolis samples from 6 foreign countries and 5 domestic regions,optimize the extraction process and evaluate the antioxidant activi-ty,so as to provide data support for improving the quality control system of propolis.METHODS The optimization of the propolis ex-traction process utilized flavonoid content as an indicator.Three flavonoid detection methods-namely,the aluminum trichloride meth-od,aluminum nitrate method,and polyamide method-were compared.The content of ethanol extract,total phenol content,and the scavenging ability of DPPH free radicals for each sample were determined.Further analysis was conducted using HPLC fingerprint pro-filing.RESULTS The propolis extract with the highest flavonoid content was obtained using 80%ethanol as the extraction solvent,operating at 50℃,with a stirring time of 3 h,ultrasonic power of 180 W,and ultrasonic time of 15 min.The aluminum trichloride method was proved to be the most effective for determining total flavonoids in propolis.While the ethanol extract,total flavonoids,and total phenols of propolis from Xinjiang,China were relatively low,their antioxidant activity exhibited superiority.HPLC analysis re-vealed,Brazilian red propolis lacked of chrysin,galangin,caffeic acid phenethyl ester and Brazilian green propolis lacked ferulic acid,apigenin,p-coumaric acid,chrysin,and pinocembrin.In contrast,the content of these four compounds in other samples varied,with the antioxidant capacity of the extracts not precisely corresponding to the compound content.CONCLUSION Propolis exhibits a complex chemical composition with significant variations among varieties.Key quality control indexes must be comprehensively consid-ered,encompassing physicochemical characteristics and biological activity.Establishing a multi-angle assessment system with a mate-rial basis-functional linkage is essential.This approach facilitates the realization of high quality and cost-effectiveness,thereby promo-ting the healthy development of the industry.

Trifluridine-tipiracil(TAS-102),as a novel fluorouracil-based chemotherapeutic agent,effectively overcomes fluorouracil resistance in colorectal cancer(CRC)through its unique pharmacological mechanisms,providing a critical treatment option for advanced CRC patients.Probiotics have shown unique value in CRC prevention and adjuvant therapy by regulating intestinal flora homeostasis and modulating host immune response.It is worth noting that the combination of chemotherapeutic drugs and probiotics not only enhances the anti-tumor activity through synergistic effects,but also reduces the adverse effects caused by chemotherapeutic drugs.Based on this,this paper systematically reviews the pharmacological properties of TAS-102 and describes its synergistic effects in combination with other antitumor drugs.It also summarizes the synergistic effect of fluorouracil drugs combined with probiotics to enhance the effectiveness and reduce the toxicity,and discusses the potential value of the combination of TAS-102 and probiotics,which provides a new research direction for optimizing the precision treatment of CRC and a scientific basis for improving the quality of life of patients.

Objective:To analyze the effects of fluorine exposure on calcium ion metabolism and the expression of related calcium-regulating proteins in the kidneys of rats.Methods:Forty-five 5-week-old specific pathogen-free male Wistar rats (weighed 90 - 120 g) were selected and divided into three groups according to the randomized numeric table: 0 (control), 50, and 100 mg/L fluorine exposure groups, with 15 rats in each group. The control group was given deionized water, while the 50 and 100 mg/L fluorine exposure groups were given sodium fluoride solutions containing 50 and 100 mg/L fluorine ions, respectively. After 12 weeks, urine samples were collected, and kidneys and blood were harvested. Urinary fluorine levels were measured using a fluoride ion-selective electrode method. Calcium ion levels in the urine, kidneys, and serum were determinated using the methylthymol blue microplate method. The protein expression levels of transient receptor potential vanilloid receptor 5 (TRPV5), calbindin-D28K (CB-D28K), sodium-calcium exchanger-1 (NCX1), Klotho and plasma membrane calcium ATPase 1b (PMCA1b) in the kidneys were detected by Western blotting and immunohistochemistry.Results:The urinary fluorine levels in the control group and the 50 and 100 mg/L fluorine exposure groups were (0.48 ± 0.09), (20.01 ± 1.68), (37.45 ± 2.45) mg/L, respectively, with statistically significant differences between the groups ( F = 929.58, P < 0.001). Significant differences in calcium ion levels in urine, kidneys, and serum were observed among the three groups ( F = 14.66, 11.09, 10.31, P < 0.05). Compared with the control group, the 100 mg/L fluorine exposure group exhibited higher levels of calcium ion in the urine and kidneys, and lower serum calcium ion levels ( P < 0.05). The results of Western blotting analysis revealed that the protein expression levels of TRPV5 and CB-D28K in the kidneys increased with the increase of fluorine exposure level ( Z = 2.11, 2.11, P = 0.035). The protein expression level of NCX1 in the kidneys showed a decreasing trend with increasing fluorine exposure level ( Z = - 2.11, P = 0.035). Significant differences were also observed in the protein expression levels of Klotho and PMCA1b among the three groups ( F = 8.93, 7.08, P < 0.05). Compared with the control group, the 100 mg/L fluorine exposure group showed higher level of Klotho protein expression and lower level of PMCA1b protein expression in the kidneys ( P < 0.05). Immunohistochemical results indicated significant differences in the protein expression levels of TRPV5, CB-D28K, NCX1, and Klotho in the kidneys of the three groups ( F = 27.56, 24.94, 16.05, 32.72, P < 0.05). Compared with the control group, the protein expression levels of TRPV5, CB-D28K, and Klotho in kidneys of 50 and 100 mg/L fluorine exposure groups were higher, while the protein expression levels of NCX1 were lower ( P < 0.05). Conclusion:Fluorine exposure may cause calcium ion metabolism disorders by regulating the expression levels of Klotho and other calcium-regulating proteins in the kidneys.