Enhancer-promoter communication is fundamental to the spatial and temporal control of gene expression. Cohesin-mediated loop extrusion has long been considered a major structural mechanism that brings distal regulatory elements into proximity with their target promoters. Recent findings from Aboreden et al. refine this view by showing that depletion of Nipped-B-like protein (NIPBL), a key regulator of cohesin loading and loop extrusion, markedly disrupts architectural chromatin loops, whereas many cis-regulatory contacts and broad post-mitotic transcriptional reactivation are only modestly affected. These observations suggest that loop extrusion is important, but not sufficient, for explaining productive regulatory communication. In this Comment, we discuss how transcriptional condensate-like assemblies may provide an additional biochemical and kinetic layer that helps convert regulatory proximity into transcriptional output. By locally enriching transcription factors, coactivators, mediator and RNA polymerase II(Pol II) around active loci, such regulatory hubs may stabilize productive enhancer-promoter encounters and modulate transcriptional activity. We further propose that transcriptional bursting provides a useful framework for understanding this conversion, because gene expression can be decomposed into burst frequency, burst duration and burst size. Integrating chromatin architecture, condensate organization and bursting dynamics may therefore provide a more complete view of how enhancer-promoter communication is re-established after mitosis and how regulatory proximity is converted into transcriptional output through mechanisms beyond loop extrusion.

Postoperative infection of internal fixation of closed fractures the lower limbs in adults represents a devastating complication, characterized by diagnostic challenges, prolonged treatment duration and high disability rates. Current management of these infections faces multiple challenges, such as difficulties in early accurate diagnosis, and various controversies about the treatment plan, leading to poor overall diagnosis and treatment results. To address these issues, based on evidence-based medicine and principles with emphasis on scientific rigor, clinical applicability and innovation, the Trauma Branch of the Chinese Medical Association, Orthopedic Branch of the Chinese Medical Doctor Association, Orthopedics Branch of the Chinese Medical Association, and Trauma Orthopedics and Polytrauma Group of the Resuscitation and Emergency Committee of the Chinese Medical Doctor Association have collaboratively organized a panel of relevant experts to develop the Guideline for diagnosis and treatment of infection after internal fixation of closed lower limb fractures in adults ( version 2025). The guideline proposed 10 recommendations, aiming to provide a foundation for standardized diagnosis and treatment of postoperative infection in adults with closed lower limb fractures.

Objective:To analyze the etiological characteristics of Clostridium ramosum DZS3717106 isolated from the blood of a patient with septic shock secondary to perianal abscess and the immunological characteristics of the patient. Methods:The isolate was subjected to morphological observation, mass spectrometry, antibiotic susceptibility testing, and 16S rRNA sequencing. Biochemical and cytological test results of the patient were collected. Flow cytometry was used to detect T cell subsets. Impacts of the virulence factors of the isolate on the host immune system were evaluated.Results:DZS3717106 was an anaerobic Clostridium with pleomorphic rod-shaped cells and spores. It was sensitive to penicillin G, piperacillin/tazobactam, and metronidazole, but resistant to clindamycin. It carried various virulence and resistance genes. The patient was immunocompromised with abnormal IL-6, IL-8, and IL-10 levels. Conclusions:Septic shock caused by Clostridium ramosum is rare, and more research is needed on the causes and epidemiology. DZS3717106 infection triggers over-activated inflammatory response in the patient, which may be closely related to the occurrence and development of septic shock.

Objective:To investigate the association of regulatory T cell (Treg) levels in peripheral blood with bronchopulmonary dysplasia (BPD) in preterm infants and its predictive value for BPD.Methods:In this case-control study, a total of 102 infants with gestational age ≤32 weeks who were hospitalized in the Neonatal Intensive Care Unit of the First Affiliated Hospital of Xinxiang Medical University from April 2022 to April 2024 were included.They were divided into a BPD group (31 cases) and a non-BPD group (71 cases) based on the diagnostic criteria of BPD.Peripheral blood samples were collected on 0 day, 7 days, 14 days, 21 days and 28 days after birth.Differences in Treg levels between the 2 groups and the relationship between Treg levels and BPD were analyzed.The independent sample t test or χ2 test was used to analyze differences between the 2 groups.One-Way ANOVA was used to compare data between groups.Multivariate Logistic regression was used to analyze the risk factors of BPD.The receiver operating characteristic (ROC) curve was used to evaluate the predictive value of Treg levels on 7 days after birth for early diagnosis of BPD. Results:Gestational age[(28.1±1.4) weeks vs.(30.9±1.0) weeks], birth weight[(1 024±243) g vs.(1 301±188) g], Apgar score at 1 minute after birth[(4.3±1.9) points vs.(7.8±1.9) points], Apgar score at 5 minutes after birth[(7.2±1.7) points vs.(9.1±1.3) points], proportion of invasive mechanical ventilation time ≥7 days [87.1%(27/31) vs.45.1%(32/71)] and oxygen inhalation time[(45.1±11.7) days vs.(19.7±7.3) days] were statistically significantly different between BPD and non-BPD groups (all P<0.05).The Treg level in the peripheral blood of preterm infants increased first and then decreased after birth, with the peak observed on 7 days after birth.On 7 days after birth, the BPD group had a significantly higher Treg level than the non-BPD group[(10.4±1.2)% vs.(8.7±1.7)%] ( P<0.05).The multivariate Logistic regression analysis showed increased Treg levels in peripheral blood on 7 days after birth ( OR=3.320, 95% CI: 1.057-10.427, P=0.040), gestational age ( OR=0.040, 95% CI: 0.003-0.446, P=0.009), invasive mechanical ventilation time ≥7 days ( OR=4.126, 95% CI: 1.301-14.125, P=0.002), and oxygen inhalation time ( OR=1.716, 95% CI: 1.317-3.933, P=0.041) were risk factors of BPD in preterm infants.The ROC curve analysis showed that the area under the curve of Treg levels on 7 days after birth for BPD prediction was 0.794, the best cut-off value was 9.35%, the sensitivity was 90.3%, and the specificity was 66.2%. Conclusions:Treg levels in the peripheral blood of preterm infants increase first and then decrease in the early stage after birth, peaking at 7 days after birth.Elevated Treg levels at 7 days after birth may have early predictive value for the occurrence of BPD in preterm infants.

Objective:To evaluate the relationship between transverse sinus stenosis (TSS) and cerebral blood flow in normal adults based on four-dimensional flow (4D Flow) MRI.Methods:The study was a cross-sectional study. Totally 81 normal volunteers who underwent magnetic resonance venography (MRV) and 4D Flow MRI were prospectively enrolled at Beijing Friendship Hospital, Capital Medical University from January 2020 to December 2022. Based on MRV evaluation of transverse sinus dysplasia, the volunteers were divided into a dysplasia group (26 cases) and a non-dysplasia group (55 cases); The area of the stenosis and the normal transverse sinus at the distal end were measured. The degree of TSS and the bilateral average transverse sinus stenosis (BA-TSS) were calculated. TSS was determined using TSS levels of 1/3, 1/2, and 2/3 as thresholds, and was divided into three groups: no TSS group, unilateral TSS group, and bilateral TSS group, with 28, 39, and 14 cases, 37, 37, and 7 cases, and 43, 36, and 2 cases, respectively. Based on 4D Flow MRI, the blood flow of the internal carotid artery, vertebral artery, superior sagittal sinus, straight sinus, and transverse sinus distal and proximal ends were measured. The cerebral blood flow (bilateral internal carotid artery blood flow+bilateral vertebral artery blood flow), venous sinus return blood flow 1 (superior sagittal sinus blood flow+straight sinus blood flow), return blood flow 2 (sum of bilateral transverse sinus distal end blood flow), return blood flow 3 (sum of bilateral transverse sinus proximal end blood flow), and the ratio of return blood flow to cerebral blood flow were calculated. Independent sample t-test was used to compare the differences between the group with and without transverse sinus dysplasia; Single factor analysis of variance was used to compare the differences between the TSS free group, unilateral TSS group, and bilateral TSS group. Based on single factor linear regression, the relationships between BA-TSS and blood flow parameters were analyzed.Results:There was no statistically significant difference in various blood flow parameters between the group with and without transverse sinus dysplasia (all P>0.05). When using 1/3, 1/2, and 2/3 as thresholds, there was no statistically significant difference in various blood flow parameters between the non TSS group, unilateral TSS group, and bilateral TSS group (all P>0.05). BA-TSS was linearly positively correlated with cerebral blood flow (β=0.986, 95% CI 0.108-1.865, P=0.028), but not linearly correlated with return blood flow 1, 2, and 3 (all P>0.05). The degree of BA-TSS was linearly negatively correlated with return blood flow 1/cerebral blood flow (β=-0.001, 95% CI -0.002-0, P=0.009) and return blood flow 2/cerebral blood flow (β=-0.001, 95% CI -0.002-0, P=0.018), but not with return blood flow 3/cerebral blood flow ( P=0.076). Conclusion:The BA-TSS degree in normal adults is positively correlated with cerebral blood inflow and negatively correlated with the proportion of venous sinus outflow.

Objective:To investigate the impact of minocycline on myocardial injury in diabetes cardiomyopathy(DCM)rats by regulating 5'-AMP activated protein kinase(AMPK)/sirtuin 1(SIRT1)/peroxisome proliferator activator receptor gamma coactiva-tor 1α(PGC-1α)signal pathway.Methods:SD rats were fed with high-fat diet for 4 weeks,and then a single intraperitoneal injection of 35 mg/kg streptozotocin was used to induce the DCM model.They were randomly grouped into model group,low-dose minocycline(20 mg/kg)group,high-dose minocycline(40 mg/kg)group,high-dose minocycline+Dorsomorphin(AMPK inhibitor,0.2 mg/kg)group,with 12 rats in each group,another 12 normal rats were fed with normal feed for 4 weeks,and then were given a single intraper-itoneal injection of the same dose of citric acid buffer,which was set as a sham operation group,after the intervention with minocy-cline and Dorsomorphin,and the fasting blood glucose(FBG),total cholesterol(TC)and triglyceride(TG)were measured;left ven-tricular ejection fraction(LVEF)and left ventricular short axis shortening(FS)were measured by ultrasound;HE staining and Mas-son staining were applied to detect the pathological morphology of myocardial tissue of rats in each group;the levels of serum and myo-cardial tissue inflammation IL-6,IL-18,and myocardial tissue oxidative stress indicators-superoxide dismutase(SOD)and malondial-dehyde(MDA)were measured with the kit;Western blot was applied to detect the expression of AMPK/SIRT1/PGC-1α pathway pro-tein in myocardial tissue of rats in each group.Results:Compared with the sham operation group,the myocardial tissue in the model group was seriously damaged,the levels of FBG,TC and TG,the cross-sectional area of myocardial cells and the proportion of myocar-dial fiber area,the levels of IL-6 and IL-18 in serum and myocardial tissue,and the level of MDA in myocardial tissue were obviously increased(P<0.05),the levels of LVEF,FS and SOD in myocardial tissue,and the protein expression of p-AMPK/AMPK,SIRT1 and PGC-1α were obviously decreased(P<0.05);compared with the model group,the myocardial tissue damage of rats in the low-dose and high-dose minocycline groups were reduced,the levels of FBG,TC and TG,the cross-sectional area of myocardial cells and the proportion of myocardial fiber area,the levels of IL-6 and IL-18 in serum and myocardial tissue,and the level of MDA in myocardial tissue were decreased(P<0.05),the LVEF,the levels of FS and SOD in myocardial tissue,and the protein expression of p-AMPK/AMPK,SIRT1 and PGC-1α were increased(P<0.05);compared with the low-dose minocycline group,the myocardial tissue damage in the high-dose minocycline group was further reduced,the levels of FBG,TC and TG,the cross-sectional area of myocardial cells and the proportion of myocardial fiber area,the levels of IL-6 and IL-18 in serum and myocardial tissue,and the level of MDA in myo-cardial tissue were further decreased(P<0.05),the levels of LVEF,FS and SOD in myocardial tissue,and the protein expression of p-AMPK/AMPK,SIRT1 and PGC-1α were further increased(P<0.05);compared with the high-dose minocycline group,the myocar-dial tissue damage of rats in the high-dose minocycline+Dorsomorphin group increased,the levels of FBG,TC and TG,the cross-sec-tional area of myocardial cells and the proportion of myocardial fiber area,the levels of IL-6 and IL-18 in serum and myocardial tis-sue,and the level of MDA in myocardial tissue were increased(P<0.05),the LVEF,the levels of FS and SOD in myocardial tissue,and the protein expression of p-AMPK/AMPK,SIRT1 and PGC-1α were decreased(P<0.05).Conclusion:Minocycline can reduce oxidative stress and inflammation in DCM rats by activating AMPK/SIRT1/PGC-1α signal,and improve glycolipid metabolism,thereby reducing myocardial injury and repairing cardiac function in rats.

Schizophrenia (SZ) stands as a severe psychiatric disorder. This study applied diffusion tensor imaging (DTI) data in conjunction with graph neural networks to distinguish SZ patients from normal controls (NCs) and showcases the superior performance of a graph neural network integrating combined fractional anisotropy and fiber number brain network features, achieving an accuracy of 73.79% in distinguishing SZ patients from NCs. Beyond mere discrimination, our study delved deeper into the advantages of utilizing white matter brain network features for identifying SZ patients through interpretable model analysis and gene expression analysis. These analyses uncovered intricate interrelationships between brain imaging markers and genetic biomarkers, providing novel insights into the neuropathological basis of SZ. In summary, our findings underscore the potential of graph neural networks applied to multimodal DTI data for enhancing SZ detection through an integrated analysis of neuroimaging and genetic features.
Humans ; Schizophrenia/pathology* ; Diffusion Tensor Imaging/methods* ; Male ; Female ; Adult ; Brain/metabolism* ; Young Adult ; Middle Aged ; White Matter/pathology* ; Gene Expression ; Nerve Net/diagnostic imaging* ; Graph Neural Networks

This study was aimed at developing an in vitro fluorescent substrate assay for the activity of leucyl aminopeptid-ase(LAP)from Echinococcus multilocularis and comparing it with the chemical chromogenic substrate enzyme activity assay.Through the establishment of reaction conditions for the fluorescent substrate-based in vitro enzyme activity assay,we com-pared the differences between the fluorescent substrate L-Leucine-7-amido-4-methylocoumarin(Leu-AMC)and the chemical chromogenic substrate L-Leucine-4-nitroanilide(Leu-pNA)through molecular docking,inhibition rates,and precision measures.Molecular docking revealed that the fluorescent substrate Leu-AMC had higher affinity for the protein than the chemical chromogenic substrate Leu-pNA.Through analysis of the effects of varying reaction conditions on fluorescence intensi-ty,we optimized the fluorescent substrate enzyme activity assay to demonstrate favorable performance at a reaction temperature of 37℃,a pH of 9.0,a protein concentration of 800 nmol/L,and a reaction duration of 60 minutes.Leu-AMC exhibited significant and distinct responses at a 5 μmol/L substrate concentration,under varying substrate conditions.The fluo-rescent substrate assay demonstrated more significant intergroup differences than the chemical chromogenic substrate assay when various inhibitors were added.This study established a fluorescence-based enzyme activity assay for leucyl aminopeptidase from Echinococcus multilocularis by using Leu-AMC as the substrate;this method demonstrated a more significant intergroup difference and sensitivity than the chemical chromogenic substrate assay.

Objective:To establish a liquid chromatography tandem mass spectrometry (LC-MS/MS) method for accurate determination of plasma Lyso-GL-3 concentration.Method:Solid phase extraction technology was used to process plasma samples, and under positive ion mode and multiple reaction monitoring (MRM) conditions, LC-MS/MS was used to determine the concentration of Lyso-GL-3. The linear range, detection and quantification limits, accuracy, precision, matrix effect, carrier effect of the method, and plasma sample stability were validated. And the accuracy of Lyso-GL-3 positive patients was compared by combining enzymatic and genetic testing results.Result:Lyso-GL-3 had good linearity in the range of 1.25-400 nmol/L. The detection limit and quantification limit were 0.15 nmol/L and 0.50 nmol/L, respectively. The spiked recovery rate was 88.78%-108.96%. The coefficient of variation ( CV) for intra batch precision, inter batch precision, and matrix effect were all less than 15%, the result of carrier effect was 0.55%. Plasma samples could be stably stored for 30 days under refrigeration conditions. The clinical conformity of the patient was 100%. Conclusion:The established LC-MS/MS detection method for plasma Lyso-GL-3 concentration takes 2.5 minutes, which is simple, fast, accurate, and reliable.