This study elucidated the structure-activity relationships (SAR) of three distinct opioid ligand series at the μ-opioid receptor (μ-OR) and investigated the ligand-dependent role of arrestin in downstream signaling. Radioligand binding assays across 13 compounds revealed that high-affinity μ-OR binding is not restricted to a single chemical scaffold. For fentanyl analogs, SAR analysis identified four key structural determinants: the N-phenethyl group (R1) is essential for μ-OR binding, the piperidine 4-position (R2) is sterically constrained and tolerates only small substituents such as carbomethoxy, the acyl side chain (R3) tolerates diverse chemical modifications including alkyl, alkoxy, and heteroaryl groups without substantial loss of affinity, and para-substitution on the phenethyl ring (R4) with electron-withdrawing groups like fluorine is well-tolerated. Analysis of non-fentanyl scaffolds (2-Methyl AP-237, W-15, and brorphine) demonstrated that specific side-chain functionalization, rather than core scaffold architecture, primarily determines binding potency. Comparison of classical opioids further revealed that structural flexibility, exemplified by methadone, can confer superior binding affinity compared to the rigid morphine scaffold. Consistent with this structural diversity, the contribution of arrestins to ERK activation varied substantially across compounds, suggesting that μ-OR-biased signaling is not dictated exclusively by intrinsic receptor properties but emerges from the interplay between receptor conformation and ligandspecific structural features. Collectively, our results provide a molecular framework for understanding opioid pharmacology with important implications for rational drug design aimed at minimizing adverse effects while maintaining analgesic efficacy.

Objective: To systematically analyze the stability and decay kinetics of coagulation factors in thawed cryoprecipitate stored at different temperatures under the new storage guidelines, and to provide an evidence basis for optimizing storage strategies. Methods: A total of 30 bags of 2U cryoprecipitate prepared at our blood center from January to June 2025 were selected. After thawing in a 37℃ water bath and thorough mixing, each bag was equally divided into two portions and stored at room temperature (20-24℃) or under refrigerated temperature (2~6℃), respectively. Dynamic sampling was performed at 0, 4, 6, 24, 30, and 120 h after thawing to measure fibrinogen (FIB) content, coagulation factor Ⅷ(FⅧ) activity, and von Willebrand factor (vWF) activity. Two-way repeated measures ANOVA was used to evaluate the effects of storage temperature, time, and their interaction. A one-phase exponential decay model was applied to fit the decay kinetics of FⅧ activity and vWF activity. Results: After thawing, FⅧ activity and vWF activity in cryoprecipitate showed a decreasing trend with prolonged storage time, and a time×temperature interaction was observed for both factors (all P< 0.001). The decay rates of FⅧ activity and vWF activity were lower under room temperature storage than under refrigerated storage, with statistically significant differences between the two groups starting from 24 h. Kinetic fitting revealed that the half-life of FⅧ activity in the room temperature group (19.83 h) was 3.4 times longer than that in the refrigerated group (5.85 h); the half-life of vWF activity in the room temperature group (204.6 h) was 5.9 times longer than that in the refrigerated group (34.6 h). FIB content remained stable throughout the observation period under both storage temperatures, with no statistically significant differences. Conclusion: Storage of thawed cryoprecipitate at room temperature effectively delays the loss of FⅧ activity and vWF activity and reduces cryoprecipitate formation induced by low temperature, providing experimental evidence for optimizing transfusion strategies based on the decay kinetics of different coagulation factors and improving the utilization efficiency of cryoprecipitate resources.

[Purpose]To analyze the diagnostic yield of quantitative fecal immunochemical test(FIT)at different cut-offs in colorectal cancer(CRC)screening.[Methods]The sequential screening method was adapted in Jiashan CRC screening program for local residents aged 40～74 years old,which included a quantitative FIT and high-risk factor questionnaire for primary screening and subsequent colonoscopy for the diagnostic screening.Subjects who participated in quantitative FIT were included in this study between September,2021 and August,2023.The positive predictive values(PPVs)for colorectal neoplasms were calculated at the cut-offs of 100,120,140,160,180 and 200 ng/mL of FIT.The Cochran-Armitage trend test was performed to compare the trend of PPVs at different cut-offs.The effects of different starting age and FIT cut-offs on requirement of colonoscopy and advanced neoplasia detection were assessed.[Results]A total of 58 256 individuals completed the quantitative FIT,and 3 106 had fecal hemoglobin concentrations＞100 ng/mL,among whom 2 186 underwent colonoscopic examination with a compliance rate of 70.38％.The colonoscopy detected 588 cases of non-advanced adenomas and 355 cases of advanced neoplasms(AN),in-cluding 30 cases of CRC and 325 cases of advanced adenomas.Progressively increasing the cut-off showed a decrease in PPVs of non-advanced adenomas and an increase of AN.The ratio of the rate of reduced requirement of colonoscopy to the missed rate of the progressive lesions was the smallest when the screening start age was 45 years old and the positive FIT threshold was set at 100 ng/mL.[Conclusion]There were significant differences in the diagnostic yield at different cut-offs of FIT.Increasing the cut-offs of FIT will elevate PPVs for the advanced neoplasms.

Objective To construct a home care readiness program for caregivers of patients with chronic heart failure based on the McMaster Family Functioning Model and explore its application effects.Methods The pro-gram was developed through literature analysis,expert correspondence and pre-testing.86 pairs of patients with chronic heart failure and their caregivers who were admitted to the Department of Cardiology of a tertiary-level hos-pital in Bengbu City were conveniently selected from December 2023 to April 2024 as the study subjects.Using the coin-flip method,the patients were randomly divided into 43 pairs in an experimental group and 43 pairs in a control group on a ward-by-ward basis.The experimental group implemented the program on the basis of routine care,and the control group was given routine care.Differences in caregiver home care readiness,caregiver caregiv-ing ability and patients' quality of life were compared between the 2 groups at the time of admission,at the time of discharge,and 1 and 3 months after discharge.Results A total of 81 pairs of patients and their caregivers completed the intervention,with 41 in the experimental group and 40 in the control group.Repeated-measures ANOVA showed that there was an interaction effect between time and group for caregiver home care readiness,caregiver caregiving ability,and patient quality of life in both groups(F=320.995,P＜0.001;F=83.303,P＜0.001;F=113.283,P＜0.001).Simple effect analyses showed that caregiver home care readiness and caregiver caregiving com-petence scores were higher in the experimental group than those in the control group at the time of discharge and at 1 and 3 months post-discharge(P＜0.001);quality of life scores of patients in the experimental group were lower than it in the control group at 1 and 3 months post-discharge(P＜0.001).Conclusion The implemen-tation of the program can effectively improve the home care readiness and caregiving ability of caregivers of pa-tients with chronic heart failure,and improve the quality of life of patients.

Objective By exploring changes of six degrees of freedom(6DOF)kinematics of the knee joint during extra weight bearing of the body trunk,the influence of extra weight on knee joint movement patterns was studied.Methods A total of 24 healthy subjects were recruited to walk/run on a treadmill at four speeds under two states:self-weight and wearing a 16 kg vest,and gait analysis was conducted.A three-dimensional(3D)portable knee kinematics analysis system based on infrared stereophotography was used to capture 6DOF movement trajectory data of the tibia relative to the femur.Results Compared to the self-weight state,when additional trunk weight was added,the knee external rotation angle was reduced at 3.6 km/h speed(1.4°-2.1°)and 5.4 km/h speed(2.2°-2.7°);the knee internal rotation angle was reduced at 10.8 km/h speed(2.1°-4.2°);the knee flexion angles was increased significantly at the speed of 3.6 km/h(1.5°-1.8°),9 km/h(1.6°-3.3°)和 10.8 km/h(1.9°-3.1°);the knee adduction angle increased at 5.4 km/h speed(0.5°-0.6°),and decreased at 10.8 km/h speed(0.9°-1.3°).At 10.8 km/h speed,the distal knee displacement(0.2-0.4 mm)was increased,and the lateral knee displacement(0.1-0.2 mm),and anterior knee displacement(0.2-0.3 mm)were significantly reduced.Conclusions The 6DOF kinematics of human knee is significantly affected by the extra trunk weight.Performance is also different at lower and higher speeds.It is suggested that there may exist a hidden injury in military training,and this study provides a kinematic basis for the occurrence of sports injury.

[Purpose]To analyze the diagnostic yield of quantitative fecal immunochemical test(FIT)at different cut-offs in colorectal cancer(CRC)screening.[Methods]The sequential screening method was adapted in Jiashan CRC screening program for local residents aged 40～74 years old,which included a quantitative FIT and high-risk factor questionnaire for primary screening and subsequent colonoscopy for the diagnostic screening.Subjects who participated in quantitative FIT were included in this study between September,2021 and August,2023.The positive predictive values(PPVs)for colorectal neoplasms were calculated at the cut-offs of 100,120,140,160,180 and 200 ng/mL of FIT.The Cochran-Armitage trend test was performed to compare the trend of PPVs at different cut-offs.The effects of different starting age and FIT cut-offs on requirement of colonoscopy and advanced neoplasia detection were assessed.[Results]A total of 58 256 individuals completed the quantitative FIT,and 3 106 had fecal hemoglobin concentrations＞100 ng/mL,among whom 2 186 underwent colonoscopic examination with a compliance rate of 70.38％.The colonoscopy detected 588 cases of non-advanced adenomas and 355 cases of advanced neoplasms(AN),in-cluding 30 cases of CRC and 325 cases of advanced adenomas.Progressively increasing the cut-off showed a decrease in PPVs of non-advanced adenomas and an increase of AN.The ratio of the rate of reduced requirement of colonoscopy to the missed rate of the progressive lesions was the smallest when the screening start age was 45 years old and the positive FIT threshold was set at 100 ng/mL.[Conclusion]There were significant differences in the diagnostic yield at different cut-offs of FIT.Increasing the cut-offs of FIT will elevate PPVs for the advanced neoplasms.

Objective To construct a home care readiness program for caregivers of patients with chronic heart failure based on the McMaster Family Functioning Model and explore its application effects.Methods The pro-gram was developed through literature analysis,expert correspondence and pre-testing.86 pairs of patients with chronic heart failure and their caregivers who were admitted to the Department of Cardiology of a tertiary-level hos-pital in Bengbu City were conveniently selected from December 2023 to April 2024 as the study subjects.Using the coin-flip method,the patients were randomly divided into 43 pairs in an experimental group and 43 pairs in a control group on a ward-by-ward basis.The experimental group implemented the program on the basis of routine care,and the control group was given routine care.Differences in caregiver home care readiness,caregiver caregiv-ing ability and patients' quality of life were compared between the 2 groups at the time of admission,at the time of discharge,and 1 and 3 months after discharge.Results A total of 81 pairs of patients and their caregivers completed the intervention,with 41 in the experimental group and 40 in the control group.Repeated-measures ANOVA showed that there was an interaction effect between time and group for caregiver home care readiness,caregiver caregiving ability,and patient quality of life in both groups(F=320.995,P＜0.001;F=83.303,P＜0.001;F=113.283,P＜0.001).Simple effect analyses showed that caregiver home care readiness and caregiver caregiving com-petence scores were higher in the experimental group than those in the control group at the time of discharge and at 1 and 3 months post-discharge(P＜0.001);quality of life scores of patients in the experimental group were lower than it in the control group at 1 and 3 months post-discharge(P＜0.001).Conclusion The implemen-tation of the program can effectively improve the home care readiness and caregiving ability of caregivers of pa-tients with chronic heart failure,and improve the quality of life of patients.

Objective To investigate the relationship between biological aging and the rate of cognitive decline in middle-aged and elderly populations.Methods Longitudinal tracking data of cognitive function were obtained from the China Health and Retirement Longitudinal Study(CHARLS).We employed the Klemera and Doubal method(KDM)to estimate biological age(BA),and calculate the biological aging index(BAI)and biological aging type(BAT).A multivariate linear regression model was employed to analyze the relationships between baseline BAI,BAT,and cognitive function scores.Based on the baseline analysis,a mixed-effects model was used to examine the longitudinal associations between baseline BAI,BAT,and cognitive function during follow-up.Results A total of 5 897 participants were included in the study.BAI was found to be negatively associated with baseline cognitive function scores,with the partial regression coefficient(β)(95％CI)being-0.185(—0.231,—0.139)(P＜0.001).Compared with the lagged aging group,the premature aging group had lower cognitive function scores(β[95％CI]:—0.741[—0.966,—0.516]).For age and sex,for each additional year of baseline BAI,cognitive function scores declined by an average of 0.012(95％CI:—0.019,—0.005)points per year after adjusting for age and sex,and declined by 0.011(95％CI:—0.018,—0.004)points per year after adjusting for other covariates.Compared with participants with lagged aging,those with premature aging experienced,on average,an additional decline of 0.042(95％CI:—0.075,0.009)points per year in cognitive function scores after adjusting for age and sex alone,and by 0.039(95％CI:—0.072,—0.007)points per year after adjusting for other covariates.Conclusion Biological aging affects the rate of cognitive decline in middle-aged and elderly populations.A higher BAI is associated with a faster decline in cognitive function.Compared with those with lagged aging,individuals with premature aging exhibit a more rapid rate of cognitive decline.

The N-methyl-D-aspartate receptor (NMDA-R) subunit GluN2B is abundantly expressed in brain regions critical for synaptic plasticity and cognitive processes. This study investigated the structure-activity relationships (SAR) of NMDA-R ligands using GluN2B as a molecular target. Thirty potential NMDA-R antagonists were categorized into two structural classes: 1-(1-phenylcyclohexyl) amines (series A) and α-amino-2-phenylcyclohexanone derivatives (series B). In series A compounds, the phenyl ring and R1 substituents were positioned at the carbon center of the cyclohexyl ring, with R2 substituents at the para- or meta-positions of the phenyl ring. SAR analysis revealed optimal binding affinity when R1 was carbonyl (C=O) and R2 was 4-methoxy (4-OMe). Series B compounds featured a cyclohexanone scaffold with NH-R1 at the α-position and a phenyl ring bearing R2 substituents at ortho-, meta-, or para-positions. Maximum binding affinity was achieved with R1 as hydrogen (H) and R2 as hydroxyl (OH). Compounds were assessed for GluN2B-mediated ERK activation to evaluate potential metabotropic signaling properties. Approximately 50% of the compounds demonstrated ERK activation through a non-ionotropic signaling cascade involving Src, phosphatidylinositol 3-kinase, and protein kinase C. This study elucidated key structural determinants for NMDA-R binding and characterized a novel metabotropic signaling pathway. Notably, our findings suggest that compounds acting as antagonists at the ionotropic site may simultaneously function as agonists through non-ionotropic mechanisms.

The N-methyl-D-aspartate receptor (NMDA-R) subunit GluN2B is abundantly expressed in brain regions critical for synaptic plasticity and cognitive processes. This study investigated the structure-activity relationships (SAR) of NMDA-R ligands using GluN2B as a molecular target. Thirty potential NMDA-R antagonists were categorized into two structural classes: 1-(1-phenylcyclohexyl) amines (series A) and α-amino-2-phenylcyclohexanone derivatives (series B). In series A compounds, the phenyl ring and R1 substituents were positioned at the carbon center of the cyclohexyl ring, with R2 substituents at the para- or meta-positions of the phenyl ring. SAR analysis revealed optimal binding affinity when R1 was carbonyl (C=O) and R2 was 4-methoxy (4-OMe). Series B compounds featured a cyclohexanone scaffold with NH-R1 at the α-position and a phenyl ring bearing R2 substituents at ortho-, meta-, or para-positions. Maximum binding affinity was achieved with R1 as hydrogen (H) and R2 as hydroxyl (OH). Compounds were assessed for GluN2B-mediated ERK activation to evaluate potential metabotropic signaling properties. Approximately 50% of the compounds demonstrated ERK activation through a non-ionotropic signaling cascade involving Src, phosphatidylinositol 3-kinase, and protein kinase C. This study elucidated key structural determinants for NMDA-R binding and characterized a novel metabotropic signaling pathway. Notably, our findings suggest that compounds acting as antagonists at the ionotropic site may simultaneously function as agonists through non-ionotropic mechanisms.