Spatiotemporal coordination of transcription preinitiation complex assembly in live cells.

Transcription initiation by RNA polymerase II (RNA Pol II) requires preinitiation complex (PIC) assembly at gene promoters. In the dynamic nucleus, where thousands of promoters are broadly distributed in chromatin, it is unclear how multiple individual components converge on any target to establish the PIC. Here we use live-cell, single-molecule tracking in S. cerevisiae to visualize constrained exploration of the nucleoplasm by PIC components and Mediator's key role in guiding this process. On chromatin, TFIID/TATA-binding protein (TBP), Mediator, and RNA Pol II instruct assembly of a short-lived PIC, which occurs infrequently but efficiently within a few seconds on average. Moreover, PIC exclusion by nucleosome encroachment underscores regulated promoter accessibility by chromatin remodeling. Thus, coordinated nuclear exploration and recruitment to accessible targets underlies dynamic PIC establishment in yeast. Our study provides a global spatiotemporal model for transcription initiation in live cells.

Colchicine usage for prevention of post atrial fibrillation ablation pericarditis in patients undergoing high-power short-duration ablation.

INTRODUCTION: Radiofrequency ablation (RFA) for atrial fibrillation (AF) has been associated with variable incidence (0.88%-10%) of pericarditis manifested as chest pain, possibly more prevalent with the advent of high-power short-duration (HPSD) ablation. This has led to the widespread use of colchicine in preventative protocols for postablation pericarditis. However, the efficacy of preventative colchicine has not been validated yet. OBJECTIVE: To evaluate the efficacy of a routine postoperative colchicine regimen (0.6 mg twice a day for 14 days post-AF ablation) for prevention of postablation pericarditis in patients undergoing HPSD ablation. METHOD: We retrospectively evaluated consecutive single-operator HPSD AF ablation procedures at our institution from June 2019 to July 2022. A colchicine protocol was introduced in June 2021 for the prevention of postablation pericarditis. All ablations were performed with 50 watts. Patients were divided into colchicine and noncolchicine groups. We recorded incidence of postablation chest pain, emergency room (ER) visit for chest pain, pericardial effusion, pericardiocentesis, any ER visit, hospitalization, AF recurrence, and cardioversion for AF within the first 30 days following ablation. We also recorded colchicine-related side effects and medication compliance. RESULTS: Two hundred and ninety-four consecutive HPSD AF ablation patients were screened for the study. After implementing the prespecified exclusion criteria, a total of 205 patients were included in the final analysis, yielding 101 patients in the colchicine group and 104 patients in the noncolchicine group. Both groups were well-matched for demographic and procedural parameters. There was no significant difference in postablation chest pain (9.9% vs. 8.6%, p = .7), pericardial effusion (2.9% vs. 0.9%, p = .1), ER visits (11.9% vs. 12.5%, p = .2), 30-day hospitalization for AF recurrence (0.9% vs. 0.96%, p = .3), and 30-day need for cardioversion for AF (3.9% vs. 5.7%, p = .2). Fifteen (15) patients had severe colchicine-related diarrhea, out of which 12 discontinued it prematurely. There were no major procedural complications in either group. CONCLUSION: In this single-operator retrospective analysis, prophylactic colchicine was not associated with significant reduction in the incidence of postablation chest pain, pericarditis, 30 day hospitalization, ER visits, or AF recurrence or need of cardioversion within first 30 days after HPSD ablation for AF. However, its usage was associated with significant diarrhea. This study concludes no additional advantage of prophylactic use of colchicine after HPSD AF ablation.

Safety of fluoroless radiofrequency catheter ablation for atrial fibrillation in patients with pre-existing cardiac implantable electronic device: A single-center study.

BACKGROUND: Radiofrequency catheter ablation (RFA) for atrial fibrillation (AF) is being increasingly performed without fluoroscopy. This study aims to determine the safety of fluoroless RFA for patients with pre-existing cardiac implantable electronic devices (CIED). METHODS: This is a single-center, single-operator, retrospective, observational study of 225 consecutive fluoroless RFA procedures for AF from June 1, 2019 to June 1, 2022. All procedures were performed with intracardiac echocardiography (ICE) support. Patients with pre-existing CIED were extracted from the database. Each CIED was interrogated at the start and end of each procedure and at 30-day follow-up. Pre- and post-procedure CIED interrogations were compared for any change in device or lead parameters. Patients were tracked for any subsequent device malfunction. RESULTS: Out of 225 fluoroless AF ablations, 25 (10.2%) had pre-existing CIED (14 dual-chamber pacemakers, three dual-chamber defibrillators, three single-chamber defibrillators, one single chamber pacemaker, and four biventricular devices). Mean patient age was 71 ± 6 years. The mean duration of indwelling CIED was 1804 ± 1645 days (range: 78-6267 days). One (4%) patient had lead-related fibrin on ICE imaging. There was no significant difference in lead(s) threshold, impedance, or sensing post procedure or at 30-day follow-up compared to pre procedure. None of the patients required lead revision. There were no intra- or post-op thromboembolic events or subsequent device infection. One patient underwent CIED extraction after 11 months for an unrelated secondary device infection. CONCLUSIONS: Radiofrequency catheter ablation for AF can be safely performed without fluoroscopy in patients with pre-existing CIED.

Complications and radiographic changes after implantation of interspinous process devices: average eight-year follow-up.

PURPOSE: This study aims to evaluate complications, clinical outcomes, and radiographic results following Coflex implantation. METHODS: We retrospectively studied 66 patients who had decompressive surgery combined with Coflex implantation to treat lumbar spinal stenosis. All imaging data were collected and examined for imaging changes. Clinical outcomes, included Oswestry Disability Index (ODI), back and leg visual analog scale (VAS) scores, were evaluated before surgery, six months after surgery and at the last follow-up. The number of complications occurring after five years of follow-up was counted. All reoperation cases were meticulously recorded. RESULTS: 66 patients were followed up for 5-14 years. The VAS and ODI scores were significantly improved compared with baseline. Heterotopic Ossification (HO) was detectable in 59 (89.4%). 26 (39.4%) patients had osteolysis at the contact site of Coflex with the spinous process. Coflex loosening was detected in 39 (60%) patients. Spinous process anastomosis was found in 34 (51.5%) patients. There was a statistically significant difference in the VAS score of back pain between patients with and without spinous process anastomosis. Nine cases of lumbar spinal restenosis were observed, and prosthesis fracture was observed in one case. CONCLUSION: Our study identified various imaging changes after Coflex implantation, and majority of them did not affect clinical outcomes. The majority of patients had HO, but osteolysis and Coflex loosening were relatively rare. The VAS score for back pain of these patients was higher if they have spinous process anastomosis. After five-year follow-up, we found lumbar spinal restenosis and prosthesis fracture cases.

Identification of gut microbiome and transcriptome changes in ulcerative colitis and pouchitis.

BACKGROUND: Pouchitis is the common postoperative complication of ulcerative colitis (UC) and is also considered as inflammatory bowel disease. The aim was to investigate the microbiological and transcriptional differences between the two illnesses. METHODS: Eighty-five participants were enrolled (37 UC, 15 healthy UC pouches, 15 pouchitis and 18 healthy volunteers) and stool samples were collected. Microbial populations were analyzed by pyrosequencing of 16S ribosomal DNA. Furthermore, transcriptome data of 119 UC and 28 pouch patients were obtained from two data sets for bioinformatics analysis. RESULTS: The results of gut microbiota community analysis showed that with aggravation of UC, intestinal microorganisms were characterized by a gradual decreased in diversity and numbers of butyrate-producing bacteria and Bacteroides. Besides, in addition to the decrease of probiotics, the proliferation of Escherichia-Shigella and Ruminococcus gnavus was observed in pouchitis which is related to multiple infection pathways. The function enrichment of differential expression genes and hub genes, as well as the immunological condition was shown to be distinct using transcriptome bioinformatics analysis between UC and pouchitis. A stronger immune response occurs in UC and may be associated with high expression of tumor necrosis factor and interleukin, while multiple hub genes such as CDK1 in pouchitis are associated with cell cycle regulation. CONCLUSIONS: The characteristics of gut microbiota disturbance and transcriptome alteration in UC and pouchitis are different. Our findings suggested that pouchitis may have a unique pathogenesis which was separated from UC.

New Meroterpenoid and Isocoumarins from the Fungus Talaromyces amestolkiae MST1-15 Collected from Coal Area.

Three new compounds including a meroterpenoid (1) and two isocoumarins (8 and 9), together with thirteen known compounds (2-7, 10-16) were isolated from the metabolites of Talaromyces amestolkiae MST1-15. Their structures were identified by a combination of spectroscopic analysis. The absolute configuration of compound 1 was elucidated on the basis of experimental and electronic circular dichroism calculation, and compounds 8 and 9 were determined by Mo2(OAc)4-induced circular dichroism experiments. Compounds 7-16 showed weak antibacterial activities against Stenotrophomonas maltophilia with MIC values ranging from 128 to 512 µg/mL (MICs of ceftriaxone sodium and levofloxacin were 128 and 0.25 µg/mL, respectively).

Development of a Deep-Learning Model for Diagnosing Lumbar Spinal Stenosis Based on CT Images.

STUDY DESIGN: Retrospective study. OBJECTIVES: This study aimed to develop an initial deep-learning (DL) model based on computerized tomography (CT) scans for diagnosing lumbar spinal stenosis. SUMMARY OF BACKGROUND DATA: Magnetic resonance imaging is commonly used for diagnosing lumbar spinal stenosis due to its high soft tissue resolution, but CT is more portable, cost-effective, and has wider regional coverage. Using DL models to improve the accuracy of CT diagnosis can effectively reduce missed diagnoses and misdiagnoses in clinical practice. MATERIALS AND METHODS: Axial lumbar spine CT scans obtained between March 2022 and September 2023 were included. The data set was divided into a training set (62.3%), a validation set (22.9%), and a control set (14.8%). All data were labeled by two spine surgeons using the widely accepted grading system for lumbar spinal stenosis. The training and validation sets were used to annotate the regions of interest by the two spine surgeons. First, a region of interest detection model and a convolutional neural network classifier were trained using the training set. After training, the model was preliminarily evaluated using a validation set. Finally, the performance of the DL model was evaluated on the control set, and a comparison was made between the model and the classification performance of specialists with varying levels of experience. RESULTS: The central stenosis grading accuracies of DL Model Version 1 and DL Model Version 2 were 88% and 83%, respectively. The lateral recess grading accuracies of DL Model Version 1 and DL Model Version 2 were 75% and 71%, respectively. CONCLUSIONS: Our preliminarily developed DL system for assessing the degree of lumbar spinal stenosis in CT, including the central canal and lateral recess, has shown similar accuracy to experienced specialist physicians. This holds great value for further development and clinical application.

Enhancing Diagnostic Accuracy of Fresh Vertebral Compression Fractures with Deep Learning Models.

STUDY DESIGN: Retrospective study. OBJECTIVES: The study aimed to develop and authenticated a deep learning model based on X-ray images to accurately diagnose fresh thoracolumbar vertebral compression fractures. SUMMARY OF BACKGROUND DATA: In clinical practice, diagnosing fresh vertebral compression fractures often requires MRI. However, due to the scarcity of MRI resources and the high time and economic costs involved, some patients may not receive timely diagnosis and treatment. Using a deep learning model combined with X-rays for diagnostic assistance could potentially serve as an alternative to MRI. METHODS: In this study, the main collection included X-ray images suspected of thoracolumbar vertebral compression fractures from the municipal shared database between December 2012 and February 2024. Deep learning models were constructed using frameworks of EfficientNet, MobileNet, and MnasNet respectively. We conducted a preliminary evaluation of the deep learning model using the validation set. The diagnostic performance of the models was evaluated using metrics such as AUC value, accuracy, sensitivity, specificity, F1 score, precision, and ROC curve. Finally, the deep learning models were compared with evaluations from two spine surgeons of different experience levels on the control set. RESULTS: This study included a total of 3025 lateral X-ray images from 2224 patients. The dataset was divided into a training set of 2388 cases, a validation set of 482 cases, and a control set of 155 cases. In the validation set, the three groups of DL models had accuracies of 83.0%, 82.4%, and 82.2%, respectively. The AUC values were 0.861, 0.852, and 0.865, respectively. In the control set, the accuracies of the three groups of DL models were 78.1%, 78.1%, and 80.7%, respectively, all higher than spinal surgeons and significantly higher than junior spine surgeon. CONCLUSION: This study developed deep learning models for detecting fresh vertebral compression fractures, demonstrating high accuracy.

[Effect of up-regulation of Decorin on expression of EGFR, C-Myc and p21 in nude mice with oral squamous cell carcinoma].

PURPOSE: To explore the effect of overexpression of DCN（decorin） gene on the expression of epidermal growth factor receptor (EGFR), cellular-myelocytomatosis viral oncogene (C-Myc) and cyclin dependent kinase inhibitor (p21)in tumor-bearing nude mice with oral squamous cell carcinoma（OSCC）. METHODS: The expression of DCN gene in human oral squamous cell carcinoma(HSC-3) was up-regulated by liposome transfection. Nude mice were used as the carrier of OSCC. H-E staining was used to determine the pathological grade of tumor-bearing tissues in each group. Immunohistochemistry was used to detect the expression of EGFR, C-Myc and p21 protein in tumor-bearing tissues of each group after DCN overexpression. RT-qPCR and Western blot were used to quantitatively detect the expression of EGFR, C-Myc and p21 in tumor-bearing tissues of each group after DCN overexpression, and to determine the effects of DCN overexpression on the expression of EGFR, C-Myc and p21 in tumor-bearing tissues of OSCC nude mice. SPSS 20.0 software package was used for statistical analysis. RESULTS: H-E staining showed that the animal model of OSCC was successfully constructed. The tumor-bearing tissues of nude mice in the plasmid group were significantly lighter than those in the empty vector group and non-transfected group(P＜0.05). IHC results showed that DCN, EGFR, C-Myc and p21 proteins were expressed in the tumor-bearing tissues of nude mice in each group, the expression of DCN,EGFR and C-Myc proteins in the plasmid group was significantly different from the other groups(P＜0.05).There was no significant differece in p21 protein expression in each group(P＞0.05). RT-qPCR and Western blot results showed that DCN, EGFR, C-Myc and p21 were expressed in diffrent degrees in tumor-bearing tissues of nude mice（P＜0.05）. CONCLUSIONS: DCN can inhibit the growth of tumor in OSCC nude mice. In tumor-bearing tissues of nude mice with OSCC, overexpression of DCN can down-regulate the expression of EGFR and C-Myc, and up-regulate the expression of p21.DCN may play an inhibitory role in the occurrence and development of OSCC.

Fecal calprotectin as an indicator in risk stratification of pouchitis following ileal pouch-anal anastomosis for ulcerative colitis.

BACKGROUND: Pouchitis is the most common complication following restorative proctocolectomy and ileal pouch-anal anastomosis (IPAA) for ulcerative colitis (UC). Fecal calprotectin (FC) is a noninvasive indicator of the intestinal inflammatory status. This study was conducted to evaluate the clinical value of the FC concentration for the diagnosis and risk assessment of pouchitis. PATIENTS AND METHODS: This retrospective study involved patients who underwent IPAA for UC at Tianjin Medical University General Hospital from January 2015 to January 2019. The patients were categorized into pouchitis and non-pouchitis groups based on their Pouchitis Disease Activity Index (PDAI) score. Laboratory indicators, including the FC concentration, were collected from both groups. RESULTS: Sixty-six patients with UC after IPAA were included in the study and divided into the non-pouchitis group (n = 40) and pouchitis group (n = 26). The correlation coefficient between the FC concentration and the PDAI score was 0.651 (p < 0.001). Receiver operating characteristic analysis showed that the FC cut-off value for predicting pouchitis was 579.60 µg/g (area under the curve, 0.938). The patients were then divided into three subgroups according to their PDAI score (0-2, 3-6, and ≥7), and significant differences in the FC concentration were found among the three subgroups. The best FC cut-off value for predicting a high risk of pouchitis (PDAI score of 3-6) was 143.25 µg/g (area under the curve, 0.876). CONCLUSIONS: FC is a useful biomarker in patients with pouchitis. Patients are advised to regularly undergo FC measurement to monitor for pouchitis. An FC concentration in the range of 143.25-579.60 µg/g is predictive of a high risk for pouchitis, and further examination and preventive treatment are necessary in such patients.KEY MESSAGESFecal calprotectin can be used to quantify pouch inflammation.Fecal calprotectin can be used to predict a high risk of pouchitis.

New perspectives on robotic pancreaticoduodenectomy: An analysis of the National Cancer Database.

BACKGROUND: Pancreatic ductal adenocarcinoma is a common malignancy. Despite all advancements, the prognosis remains, poor with an overall 5-year survival of only 10.8%. Recently, a robotic platform has become an attractive tool for treating pancreatic cancer (PC). While recent studies indicated improved lymph node (LN) harvest during robotic pancreaticoduodenectomy (PD), data on long-term outcomes are insufficient. AIM: To evaluate absolute LN harvest during PD. Secondary outcomes included evaluating the association between LN harvest and short- and long-term oncological outcomes for three different surgical approaches. METHODS: We conducted an analysis of the National Cancer Database, including patients diagnosed with PC who underwent open, laparoscopic, or robotic PD in 2010-2018. One-way analysis of variance was used to compare continuous variables, chi-square test - for categorical. Overall survival was defined as the time between surgery and death. Median survival time was estimated with the Kaplan-Meier method, and groups were compared with the Wilcoxon test. A Cox proportional hazards model was used to assess the association of covariates with survival after controlling for patient characteristics and procedure type. RESULTS: 17169 patients were included, 8859 (52%) males; mean age 65; 14509 (85%) white. 13816 (80.5%) patients had an open PD, 2677 (15.6%) and 676 (3.9%) - laparoscopic and robotic PD respectively. Mean comorbidity index (Charlson-Deyo Score) 0.50. On average, 18.84 LNs were harvested. Mean LN harvest during open, laparoscopic and robotic PD was 18.59, 19.65 and 20.70 respectively (P < 0.001). On average 2.49 LNs were positive for cancer and did not differ by the procedure type (P = 0.26). Vascular invasion was noted in 42.6% of LNs and did differ by the approach: 42.1% for open, 44.0% for laparoscopic and 47.2% for robotic PD (P = 0.015). Median survival for open PD was 26.1 mo, laparoscopic - 27.2 mo, robotic - 29.1 mo (P = 0.064). Survival was associated with higher LN harvest, while higher number of positive LNs was associated with higher mortality. CONCLUSION: Our study suggests that robotic PD is associated with increased intraoperative LN harvest and has comparable short-term oncological outcomes and survival compared to open and laparoscopic approaches.

Chemical constituents of Aspergillus udagawae isolated from the soil of the Xingren coal areas and their antibacterial activities.

A new helvolic acid derivative (1), together with nine known compounds (2-10) were isolated from the metabolites of Aspergillus udagawae MST1-10 with the bioassay-guided fractionation method. Their structures were identified on the basis of spectroscopic analysis. The absolute configuration of compound 1 was elucidated through NOESY and ECD spectra. Compound 2 displayed significant antibacterial activities against Stenotrophomonas maltophilia with MIC value of 2 µg/mL (Trimethoprim, MIC = 64 µg/mL), and with biofilm inhibition rates of 96.41%, 87.77%, and 41.70% at 4MIC, 2MIC, and MIC, respectively.

[Effects of Biochar Application on Yellow Soil Nutrients and Enzyme Activities].

Due to its special physical and chemical properties, biochar is widely used as a multi-beneficial amendment to improve soil quality. Soil nutrient content and enzyme activities are important chemical and biological factors indicating soil quality. Despite increased interest and studies, a knowledge gap remains regarding the ability of biochar to assess soil nutrient content and enzyme activities due to differences in biochar application amount and soil texture. In the present study, the effects of different amounts of biochar application (CK:0 t·hm-2, B5:5 t·hm-2, B10:10 t·hm-2, B20:20 t·hm-2, and B50:50 t·hm-2) on soil nutrient content and enzyme activities were studied based on a field experiment on typical yellow soil in Guizhou province, southwest China. Structural equation models (SEM) were used to quantitatively evaluate the direct or indirect effects of biochar application on soil nutrient content and enzyme activities. The results showed that soil pH, electrical conductivity (EC), soil organic carbon (SOC), alkaline hydrolysis nitrogen (AHN), available phosphorus (AP), and available potassium (AK) increased with the applied amount of biochar. With the increase in biochar application amount, the activities of soil catalase and urease showed first an increasing and then a decreasing trend, and the activities of soil sucrase and phosphatase showed an almost constant increasing trend (P<0.05). The highest activities of soil catalase, urease, and phosphatase were recorded under treatment B10. A relatively high activity of soil sucrose was also observed under treatment B10. With the same amount of biochar application, soil pH and the content of soil AHN, AP, and AK in treatments after four months of biochar application were greater than those after 12 months. After 12 months of biochar application treatment, the contents of SOC and EC were greater than those at four months. Compared to those in treatments after four months of biochar application, activities of soil urease and phosphatase increased, activities of soil catalase decreased, and activities of soil sucrose did not obviously change after 12 months of biochar application. The results of SEM showed that biochar application directly decreased activities of soil catalase and indirectly promoted activities of soil sucrase and phosphatase by increasing soil pH, EC, AHN, AK, and AP. In conclusion, the amount and duration of biochar application significantly increased soil nutrient content, directly and indirectly affecting soil enzyme activities. Based on the results of the presents study, biochar application at 10 t·hm-2 was recommended for acidic yellow soil.

Catheter ablation for atrial fibrillation can be safely performed without invasive hemodynamic monitoring: A multi-center study.

BACKGROUND: Arterial invasive monitoring is the most common method in the USA for hemodynamic monitoring during atrial fibrillation (AF) ablation. Although studies have shown favorable comparison between non-invasive and invasive hemodynamic monitoring (IHM) in non-cardiac procedures under general anesthesia, limited data is available for complex cardiac procedures such as AF ablation in the USA. With progressive improvement in AF ablation procedural safety, particularly with routine use of intracardiac echocardiography (ICE) to monitor for pericardial effusion, it is unclear if invasive hemodynamic monitoring provides any advantage over non-invasive methods. Therefore, the purpose of this study is to determine whether noninvasive hemodynamic monitoring is non-inferior to invasive hemodynamic monitoring during AF ablation under general anesthesia in patients without major cardiac structural abnormality. METHODS: A multi-center retrospective data of AF ablation from July 2019 to December 2020 was extracted. A total of three hundred and sixty-two patients (362) were included, which were divided into group A (non-invasive hemodynamic monitoring) and group B (invasive hemodynamic monitoring). The primary outcome was to compare procedural safety between the two groups. RESULTS: Out of 362 patients, 184 (51%) received non-invasive and 178 (49%) received invasive hemodynamic monitoring with similar baseline characteristics. There was no significant difference between the two groups in complication rates (groin hematoma, pericardial effusion, cardiac tamponade). Mean procedure time was longer in group B with 3.35% arterial site discomfort. Urgent arterial access was required in only 1 patient in group A. CONCLUSION: This retrospective multicenter study strongly suggests that catheter ablation for atrial fibrillation under general anesthesia can be safely performed with noninvasive hemodynamic monitoring without requiring arterial access, with potential benefit in procedural duration and cost.

Antibacterial activities of the chemical constituents of Schizophyllum commune MST7-3 collected from coal area.

Two fusidane-type active compounds (6 and 7) and five new ones (1-5), along with other nine known compounds (8-16) were isolated from the metabolites of Schizophyllum commune MST7-3. Their structures were elucidated on the basis of spectroscopic analysis. The absolute configurations of compounds 2 and 3 were established by Mosher's method and optical rotation. Compounds 6 and 7 showed significant antibacterial activities against Stenotrophomonas maltophilia with MIC values of 4 µg/mL and 16 µg/mL, respectively.

A New Rat Model of Pouchitis After Proctocolectomy and Ileal Pouch-Anal Anastomosis Using 2,4,6-Trinitrobenzene Sulfonic Acid.

BACKGROUND: Pouchitis is a common complication after ileal pouch-anal anastomosis (IPAA) in patients with ulcerative colitis. However, an ideal model remains lacking. Therefore, we aimed to establish an appropriate model resembling human pouchitis. METHODS: Sprague-Dawley rats were randomly assigned to five groups: TNBS group, DSS group, NS group (following IPAA procedure, administrated with TNBS enema, DSS orally, normal saline enema, respectively), NI group (underwent IPAA), and sham group (underwent switch abdominal surgery). General status, weight change, hematochezia, and fecal scores were recorded. Fecal microbiota were counted under a microscope and analyzed by 16S rRNA gene high-throughput sequencing. Specimens of ileal pouch and small intestine (proximal, mid, distal) were collected to evaluate myeloperoxidase and occludin expression by immunohistochemistry and mRNA expression of pro-inflammatory markers by PCR. RESULTS: General status, hematochezia, fecal score, and increased mRNA expression of interleukin-6 and TNF-α in the TNBS group were similar to those in the DSS group, whereas the TNBS-induced model displayed a more stable weight change and more serious dysbacteriosis, not only was fecal bacterial diversity reduced, the dominant microbiota was altered. Histopathology scores of the distal small intestine in the TNBS group were lower compared with those in the DSS group (P < 0.05). A significant difference in myeloperoxidase and occludin expression in the small intestine was also detected between the TNBS and DSS groups. CONCLUSIONS: Our model mimicked the characteristics of human pouchitis and avoided potential side effects in the small intestine, and thus could be employed for further research.

Single-molecule imaging of chromatin remodelers reveals role of ATPase in promoting fast kinetics of target search and dissociation from chromatin.

Conserved ATP-dependent chromatin remodelers establish and maintain genome-wide chromatin architectures of regulatory DNA during cellular lifespan, but the temporal interactions between remodelers and chromatin targets have been obscure. We performed live-cell single-molecule tracking for RSC, SWI/SNF, CHD1, ISW1, ISW2, and INO80 remodeling complexes in budding yeast and detected hyperkinetic behaviors for chromatin-bound molecules that frequently transition to the free state for all complexes. Chromatin-bound remodelers display notably higher diffusion than nucleosomal histones, and strikingly fast dissociation kinetics with 4-7 s mean residence times. These enhanced dynamics require ATP binding or hydrolysis by the catalytic ATPase, uncovering an additional function to its established role in nucleosome remodeling. Kinetic simulations show that multiple remodelers can repeatedly occupy the same promoter region on a timescale of minutes, implicating an unending 'tug-of-war' that controls a temporally shifting window of accessibility for the transcription initiation machinery.

Enteral nutrition combined with glutamine promotes recovery after ileal pouch-anal anastomosis in rats.

AIM: To assess the effect of enteral nutrition (EN) supplemented with glutamine on recovery after ileal pouch-anal anastomosis (IPAA) in rats, to provide an experimental basis for nutritional support in patients with ulcerative colitis (UC) after IPAA. METHODS: Male Sprague-Dawley (SD) rats were randomly divided into three groups (n = 8) after IPAA operation using a microsurgical technique. From the third postoperative day, rats in the control group, EN group, and immune nutrition (IN) group were fed standard rat chow, short peptide EN, and short peptide EN combined with glutamine ad libitum, respectively. The rats' general condition was observed throughout the study. Serum levels of total protein (TP), albumin (ALB), prealbumin (PA), and transferrin (TF) were detected on the 30th postoperative day, using an automatic biochemical analyzer. The ileal pouch mucosa was stained with hematoxylin and eosin (HE), and occludin protein levels were detected by immunohistochemistry. RESULTS: The body weight of rats in the EN group (359.20 ± 10.06 g) was significantly higher than that in the control group (344.00 ± 9.66 g) (P < 0.05) and lower than that in the IN group (373.60 ± 9.86 g) (P < 0.05) on the 30th postoperative day. The levels of serum TP, ALB, PA, and TF in the EN group were significantly higher than those in the control group (P < 0.01 for all) and lower than those in the IN group (P < 0.05 for all). Histopathological score (EN: 0.80 ± 0.37; IN: 0.60 ± 0.40; control group: 2.29 ± 0.18) and expression level of occludin protein (EN: 0.182 ± 0.054; IN: 0.188 ± 0.048; control group: 0.127 ± 0.032) were significantly lower in the control group compared with the EN and IN groups (P < 0.05 for all), but there were no significant differences between the latter two groups (P > 0.05 for all). CONCLUSION: EN combined with glutamine may effectively improve nutritional status after IPAA. Our results suggest a benefit of glutamine supplementation in EN for UC patients undergoing IPAA, although human studies are required to confirm this finding.