Primary pigment dispersion syndrome(PDS)is characterized by pigment granules released from the pigment epithelium of iris, and their deposition in anterior segment of eye, particularly in the trabecular meshwork(TM). This condition may lead to elevated intraocular pressure(IOP),which further causes optic nerve damage, and progresses to pigmentary glaucoma(PG). PDS predominantly affects young myopic individuals and shows heterogeneous clinical manifestations. It may occur sporadically or in familial inheritance. It has been reported that the pathogenic genes include those involved in melanogenesis and melanosome homeostasis(e.g., PMEL, MC1R, SLC45A2, and TYR), and genes related to ocular development and anterior segment formation(e.g., CPAMD8, GSAP, and GRM5).The pathogenesis of PDS is closely associated with posterior iris concavity and reverse pupillary block, which may change the dynamics of aqueous humor, along with persistent liberation of pigmented granules by friction of iris and zonules. Pigmented granules accumulating in the TM may cause mechanical obstruction of TM, and increase the phagocytic burden of the cells, and result in cellular dysfunction and structural damage of TM. All these changes contribute to sustained elevation of IOP and optic neuropathy. Primary management of PDS involves regular follow-up and assessment of the risk of IOP elevation. Laser peripheral iridotomy may be considered to reduce posterior iris concavity in PDS. Treatment of PG focuses on IOP control for long term, which include topical medications, laser trabeculoplasty, and filtering or drainage surgery. Development of experimental animal models harboring human pathogenic genes and exhibiting PDS phenotypes is needed to facilitate in-depth research into the pathogenesis of PDS.

Background: Surgeons face challenges in selecting cost-effective and biologically active agents for rotator cuff healing, given the numerous commercial products available, such as polydeoxyribonucleotide (PDRN) and atelocollagen (ATC). However, the precise efficacy of PDRN and ATC in rotator cuff healing remains debatable, and there is currently a lack of studies directly comparing the effects of the 2 agents on repaired cuff tendons. Therefore, the purpose of this study was to compare the efficacy of PDRN and ATC on bone-to-tendon interface (BTI) healing using a chronic rotator cuff tear (RCT) model in rabbits. Methods: Forty-eight rabbits were randomly divided into 3 groups. To create chronic RCT models, transected tendons were left untreated for 6 weeks, and then were repaired in a transosseous manner with PDRN and ATC injection into the repair site according to group allocation (group A: saline, group B: PDRN, group C: ATC; n = 16 per group). Genetic and immunofluorescence analyses were performed at 4 weeks after surgery. Furthermore, genetic, histologic, and biomechanical analyses were performed at 12 weeks after surgery. Results: At 4 weeks after surgery, ATC-injected shoulders showed the highest mRNA expression levels of collagen type I alpha 1 and aggrecan compared to the other 2 groups (p < 0.001 and p = 0.002, respectively). Meanwhile, there was more preliminary fibrocartilaginous matrix formation in the ATC-injected group. At 12 weeks after surgery, ATC-injected shoulders demonstrated better collagen fiber continuity and orientation, denser collagen fibers, a more mature bone-to-tendon junction, and greater fibrocartilage layer formation compared to the other 2 groups (all p < 0.001). Furthermore, ATC-injected shoulders also demonstrated a significantly higher load-to-failure value (40.4 ± 4.5 N/kg) than the remaining groups (group A, 26.7 ± 3.0 N/kg; group B, 32.8 ± 4.2 N/kg; p < 0.001). Conclusions ATC demonstrated superior efficacy in promoting BTI healing following surgical repair in a chronic RCT model of rabbits.

Objective To construct a dynamic prediction model for JC polyomavirus (JCV) reactivation after kidney transplantation. Methods A retrospective analysis was conducted on the clinical data of 128 recipients who met the inclusion criteria and received kidney transplantation in Nanfang Hospital, Southern Medical University, from June 2021 to December 2024. Dynamic Cox regression and dynamic restricted mean survival time (RMST) regression based on the landmark method were adopted to establish the dynamic prediction models, and Monte Carlo cross-validation was used to evaluate model performance. Results The dynamic models could predict the incidence and onset time of JCV reactivation within the subsequent 3 months according to covariates at each landmark time point from the 1st to the 6th month after transplantation. Remuzzi score, body mass index and warm ischemia time were independent risk factors for JCV reactivation, while a history of urinary BK polyomavirus reactivation served as a protective factor. The median values of the area under the curve, C-index and Brier score of the dynamic Cox model were 0.873, 0.851 and 0.065 respectively, and the C-index of the dynamic RMST model was 0.829, all of which were superior to those of the static model. Conclusions The landmark-based dynamic models exhibit excellent predictive performance, which may integrate baseline data and post-transplant follow-up information to realize dynamic assessment of the risk and time window of JCV reactivation, thereby providing evidence for optimizing post-operative monitoring and individualized intervention strategies.

ObjectiveThe nucleolar protein PES1 (Pescadillo homolog 1) plays critical roles in ribosome biogenesis and cell cycle regulation, yet its involvement in cellular senescence remains poorly understood. This study aimed to comprehensively investigate the functional consequences of PES1 suppression in cellular senescence and elucidate the molecular mechanisms underlying its regulatory role. MethodsInitially, we assessed PES1 expression patterns in two distinct senescence models: replicative senescent mouse embryonic fibroblasts (MEFs) and doxorubicin-induced senescent human hepatocellular carcinoma HepG2 cells. Subsequently, PES1 expression was specifically downregulated using siRNA-mediated knockdown in these cell lines as well as additional relevant cell types. Cellular proliferation and senescence were assessed by EdU incorporation and SA-β-gal staining assays, respectively. The expression of senescence-associated proteins (p53, p21, and Rb) and SASP factors (IL-6, IL-1β, and IL-8) were analyzed by Western blot or qPCR. Furthermore, Northern blot and immunofluorescence were employed to evaluate pre-rRNA processing and nucleolar morphology. ResultsPES1 expression was significantly downregulated in senescent MEFs and HepG2 cells. PES1 knockdown resulted in decreased EdU-positive cells and increased SA‑β‑gal-positive cells, indicating proliferation inhibition and senescence induction. Mechanistically, PES1 suppression activated the p53-p21 pathway without affecting Rb expression, while upregulating IL-6, IL-1β, and IL-8 production. Notably, PES1 depletion impaired pre-rRNA maturation and induced nucleolar stress, as evidenced by aberrant nucleolar morphology. ConclusionOur findings demonstrate that PES1 deficiency triggers nucleolar stress and promotes p53-dependent (but Rb-independent) cellular senescence, highlighting its crucial role in maintaining nucleolar homeostasis and regulating senescence-associated pathways.

Background Diesel engines are widely used in transportation, agriculture, construction, industry, and other fields. Diesel exhaust, classified as a Group 1 carcinogen, emits particles (DEP) that can penetrate deep into the respiratory tract, posing significant health risks. DEP pollution is particularly severe in confined environments, necessitating effective control measures. Objective Under laboratory simulation conditions, to explore the spatiotemporal distribution characteristics of the mass and number concentrations of DEP as it diffuses indoors and to reveal the effects of ventilation and additional airflow on indoor DEP pollution levels. Methods A diesel engine was placed in a laboratory (length 3.39 m × width 2.85 m × height 2.4 m) with its exhaust emitted from east to west. An air purifier was installed 1 m south of the engine. Eight measurement points (1 m horizontal distance from the exhaust outlet, height: 1 m/1.5 m) were setup to monitor DEP concentrations using portable laser particle sizers. The effects of engine power (4.05 kW vs. 5.15 kW), ventilation (maximum airflow: 600 m³·h⁻¹), additional airflow intensity (low and high), and direction (forward/reverse) on DEP pollution were analyzed. DEP levels of 5 diesel vehicle models were also compared. Results The mass and number concentrations of DEP indoors increased immediately after the diesel engine started. The peak mass concentration time at the eastern measurement point (−1, 0) m opposite to the exhaust direction (17.70 min) was significantly longer than that at the western (1, 0) m (16.20 min), southern (0, -1) m (14.45 min), and northern (0, 1) m (12.70 min) points (P<0.05), with no significant differences between the other points (western, southern, and northern) (P>0.05). The northern point (0, 1) m exhibited the highest DEP mass and number concentration peaks (174.62 μg·m⁻³, 1319.85 p·cm⁻³), significantly exceeding those at the southern (0, −1) m (129.89 μg·m⁻³, 1175.24 p·cm⁻³), eastern (−1, 0) m (140.12 μg·m⁻³, 1120.53 p·cm⁻³), and western (1, 0) m (147.60 μg·m⁻³, 818.62 p·cm⁻³) points (P<0.05), and no significant differences were observed among other points (P>0.05). There were no significant differences in peak DEP mass and number concentrations by measurement heights (P>0.05). Diesel engine power, ventilation, airflow intensity, and airflow direction had no significant effect on the time of peak DEP concentration (P>0.05). However, higher engine power (5.15 kW) produced greater DEP peaks [(186.66±19.29) μg·m⁻³, (1382.79±122.56) p·cm⁻³] than the 4.05 kW engine power [(168.41±12.65) μg·m⁻³, (1284.45±71.30) p·cm⁻³] (P<0.05). The peak mass concentration [(342.04±35.03) μg·m⁻³] and number concentration [(1886.87±57.91) p·cm⁻³] of DEP in the non-ventilated group were significantly higher than those in the ventilated group [(186.66±19.29) μg·m⁻³, (1382.79±122.56) p·cm⁻³] (P<0.001). Forward airflow elevated DEP mass concentrations compared to reverse airflow (287.71 μg·m⁻³ vs. 243.74 μg·m⁻³, t=−2.592, P=0.009), but no effects on DEP number concentration (P>0.05). Significant differences in mass concentration were observed among selected 5 vehicle models (Z=38.109, P<0.001). Conclusion The operation of diesel engines will emit a large amount of particulate matter, causing pollution in enclosed spaces. Diesel engines with greater power have higher levels of DEP pollution emissions. Based on the spatiotemporal distribution characteristics, it is recommended to set the operation position in the reverse direction of exhaust emissions and close to air purifiers, while avoiding the use of additional air flow equipment.

Objective To observe the difference of bone micro-structure in different regions of proximal femur,micro-CT scanning was performed on 30 proximal femur specimens to explain the mechanism of proximal femur fracture and to provide anatomical basis for prosthesis design.Methods Totally 30 intact proximal femur specimens were obtained from 60-80 year-old cadavers.Micro-CT scanning was used to measure the trabecular thickness(Tb.Th),trabecular number(Tb.N),trabecular space(Tb.Sp),connectivity(Conn)and bone mineral density(BMD)and other parameters in 7 regions of proximal femur,including proximal pressure trabecular(PPT),distal pressure trabecular(DPT),femoral head-neck junction(FHNJ),head and neck of femoral neck(HNFN),the base of femoral neck(BPFN),intertrochanteric line(IL)and greater trochanter(GT).Results The bone mineral density of IL and GT were higher than those of BPFN,FHNJ,DPT and PPT.The trabecular thickness of GT was the largest,followed by IL,BPFN and HNFN,and the smallest was FHNJ,DPT and PPT.The trabecular space of IL was larger than that of GT,and the data of both were larger than those of other parts,among which DPT and PPT were the smallest.The trabecular number of IL and GT were the smallest,BPFN,HNFN and FHNJ were larger,and DPT was the largest.The volume fraction of IL was the smallest,BPFN and HNFN were larger,DPT and PPT were the largest.Conclusion The bone density,trabecular thickness,bone volume,and total volume of GT and IL in the proximal femur of elderly patients are all relatively large,so the reason for the high incidence of fractures is not due to weak internal bone microstructure;The bone density,trabecular thickness,and trabecular gap at the proximal and distal ends of the vertical trabecular bone are relatively small.If it is necessary to perform core decompression for prosthesis filling at this location,the design should be conducive to the mechanical conduction of the prosthesis and the regeneration of surrounding bone tissue.

Objective: To evaluate the feasibility of dynamic contrast-enhanced MRI (DCE-MRI) in differentiating tumor deposits (TDs) from metastatic lymph nodes (MLNs) in rectal cancer. Materials and Methods: A retrospective analysis was conducted on 70 patients with rectal cancer, including 168 lesions (70 TDs and 98 MLNs confirmed by histopathology), who underwent pretreatment MRI and subsequent surgery between March 2019 and December 2022. The morphological characteristics of TDs and MLNs, along with quantitative parameters derived from DCE-MRI (K trans , kep, and v e) and DWI (ADCmin, ADCmax, and ADCmean), were analyzed and compared between the two groups.Multivariable binary logistic regression and receiver operating characteristic (ROC) curve analyses were performed to assess the diagnostic performance of significant individual quantitative parameters and combined parameters in distinguishing TDs from MLNs. Results: All morphological features, including size, shape, border, and signal intensity, as well as all DCE-MRI parameters showed significant differences between TDs and MLNs (all P < 0.05). However, ADC values did not demonstrate significant differences (all P > 0.05). Among the single quantitative parameters, v e had the highest diagnostic accuracy, with an area under the ROC curve (AUC) of 0.772 for distinguishing TDs from MLNs. A multivariable logistic regression model incorporating short axis, border, v e, and ADC mean improved diagnostic performance, achieving an AUC of 0.833 (P = 0.027). Conclusion The combination of morphological features, DCE-MRI parameters, and ADC values can effectively aid in the preoperative differentiation of TDs from MLNs in rectal cancer.

Objective:To investigate the value of biparametric-MRI (bpMRI) based peritumoral radiomics for preoperative prediction of extraprostatic extension (EPE) in prostate cancer (PCa).Methods:In this cross-sectional study, consecutive bpMRI of patients undergoing prostatectomy for PCa were retrospectively collected from the First Medical Center (center 1) and the Third Medical Center (center 2) of Chinese PLA General Hospital. A total of 274 patients were finally enrolled. Patients at center 1 from January 2020 to December 2022 were randomly divided into a training set (149 cases) and an internal validation set (63 cases) by stratified random sampling. Patients at center 2 from January 2023 to March 2024 were assigned to the external test set (62 cases). Patients were categorized into EPE-positive group and EPE-negative group according to pathological assessment postoperatively. In the training set, there were 49 cases in EPE-positive group and 100 cases in EPE-negative group. In the internal validation set, there were 26 cases in EPE-positive group and 37 cases in EPE-negative group. In the external test set, there were 22 cases in EPE-positive group and 40 cases in EPE-negative group. Axial T 2WI and apparent diffusion coefficient (ADC) images were manually annotated to obtain index lesion regions of interest (ROIs), with the peritumoral ROIs subsequently delineated by semi-automatic segmentation technique. Radiomics features were extracted from intra-tumoral, peri-tumoral, and intra-tumoral plus peri-tumoral ROIs. The training set data was employed to select and optimize features to build the radiomics models. The logistic regression analysis was used to develop radiomics, clinical, and integrated models. The predictive performance was assessed by the area under the receiver operating characteristic curve (AUC) in the external test set, and compared by the DeLong test. The sensitivity and specificity were compared by the exact McNemar test. Results:In the external test set, the peri-tumoral radiomics model based on bpMRI showed the highest performance in evaluating EPE, with an AUC of 0.739 (95% CI 0.611-0.842), which was identified as the optimal radiomics model. EPE grade ( OR=6.151, 95% CI 3.371-11.226, P<0.001) was incorporated into the clinical model, with an AUC of 0.780 (95% CI 0.657-0.875) in the external test set. The integrated model had an AUC of 0.817 (95% CI 0.698-0.904) in the external test set. There was no statistically significant difference in comparisons of AUCs among the three models (all P>0.05). The sensitivity of the integrated model (68.2%) showed no significant difference from those of the clinical model and the optimal radiomics model (77.3% and 86.4%, respectively; P=0.500 and P=0.289). However, the specificity of the integrated model (85.0%) was significantly higher than those of the clinical model (67.5%, P=0.016) and the optimal radiomics model (50.0%, P<0.001). Conclusion:A bpMRI-based peritumoral radiomics integrating clinical model demonstrates high performance for preoperative prediction of EPE in PCa.

The medical mask,which is used as an important tool of preventing the spread of respiratory diseases,can effectively block the transmission of biological aerosols.The detection for the filtration efficiency of bacteria in medical mask is particular importance.The Andersen sampler,is one kind of device that samples microbial aerosols,is widely used in the inspection for the filtration efficiency for bacteria in medical masks.It mainly consists of six impactors with different pore sizes.It simulates the deposition process of the most of particles at different positions in respiratory system through the bacterial particles in biological aerosols impact respectively the surface of petri dishes with agar under different pore sizes.This paper explored the development background,structure and sampling principle,operation and counting procedures of the Andersen sampler,as well as its application and importance in the inspection for the filtration efficiency for bacteria in medical mask.

Objective To compare the application effects of plankton multiplex polymerase chain reac-tion-capillary electrophoresis(PCR-CE),SYBR Green Ⅰ real-time quantitative PCR(qPCR)and microwave digestion-vacuum filtration-automated scanning electron microscopy(MD-VF-Auto SEM)in the diagnosis of drowning.Methods Lung,liver and kidney tissues from 212 drowned corpses and 30 non-drowned corpses were examined respectively by the three drowning-related plankton testing methods,and the detection rates of plankton in each tissue by three methods were compared.Results In drowned corpses,the total detection rates of PCR-CE,qPCR,and MD-VF-Auto SEM were 93.9%,96.2%,and 95.3%,respectively,with no statistically significant difference(P>0.05).The detection rate of lung tissue by MD-VF-Auto SEM(100%)was higher than those of PCR-CE and qPCR(P<0.05),and there was no significant difference in the detection rates of the three methods in liver or kidney tissues(P>0.05).In non-drowning corpses,a small number of diatoms(less than 10 cells/10 g)were detected by MD-VF-Auto SEM method,only in liver and kidney tissues,while the other two methods yielded negative results for all tissues.Conclusion All three methods have good efficacy in the examination of drowned corpses.The MD-VF-Auto SEM method directly observes diatom morpho-logical characteristics through scanning electron microscopy,and the qualitative and quantitative analy-ses are intuitive and accurate.It has great advantages in the examination of difficult degradation samples.The PCR-CE method and qPCR method have a low sample demand(0.5 g),are easy to operate and have short detection time(4-7 h).They are easy to be applied in the grassroots depart-ments and are suitable for the rapid determination of drowned corpses in routin cases.The combina-tion of the two DNA methods with the MD-VF-Auto SEM method can increase the detection rate of plankton,ensuring the reliability of examination results.This combined use is of significant importance in the application of drowning diagnosis.