Topoisomerases I and II facilitate condensin DC translocation to organize and repress X chromosomes in C. elegans.

Condensins are evolutionarily conserved molecular motors that translocate along DNA and form loops. To address how DNA topology affects condensin translocation, we applied auxin-inducible degradation of topoisomerases I and II and analyzed the binding and function of an interphase condensin that mediates X chromosome dosage compensation in C. elegans. TOP-2 depletion reduced long-range spreading of condensin-DC (dosage compensation) from its recruitment sites and shortened 3D DNA contacts measured by Hi-C. TOP-1 depletion did not affect long-range spreading but resulted in condensin-DC accumulation within expressed gene bodies. Both TOP-1 and TOP-2 depletion resulted in X chromosome derepression, indicating that condensin-DC translocation at both scales is required for its function. Together, the distinct effects of TOP-1 and TOP-2 suggest two distinct modes of condensin-DC association with chromatin: long-range DNA loop extrusion that requires decatenation/unknotting of DNA and short-range translocation across genes that requires resolution of transcription-induced supercoiling.

Endoscopic closure of large gastric defects with a novel through-the-scope closing device in a porcine model (with videos).

BACKGROUND AND AIMS: After endoscopic full-thickness resection (EFTR), defects require a reliable and sustained closure. We present a novel, through-the-scope "bow-tie" (TTS-BT) closing device enabling direct defect closure without scope withdrawal. This preclinical study aimed to evaluate the feasibility and safety of this device for large defect closure after EFTR in a porcine model. METHODS: Exposed EFTR was performed for virtual lesions >2 cm in the stomach of 12 pigs. Subsequently, TTS-BT closing devices were used for defect closure. Conventional metal clips were used to close any remaining defects. Gastroscopy was performed for 8 weeks to examine the wound sites, and the pigs were subsequently killed. After killing the pigs, the wound healing was histologically verified by hematoxylin and eosin staining. The primary outcome was a successful closure rate; secondary outcomes were complete healing rate, closure time, and incidence of adverse events. RESULTS: The median long and short diameters of perforations were 4.0 cm (range, 3.0-6.0 cm) and 3.0 cm (range, 2.0-4.0 cm), respectively. Defect closure using novel TTS-BT closure devices and conventional metal clips was successfully performed in all pigs. Complete healing was achieved in the defects of 12 pigs. The median closure time was 13 minutes (range, 9-38 minutes). No serious adverse events occurred during the 8-week follow-up. CONCLUSIONS: The novel TTS-BT closure device is feasible and safe for closing large gastric perforations and could be a promising tool for clinical practice.

First Fully Endoscopic End-to-End Colonic Anastomoses With a Novel Endoscopic Device: A Feasibility Study in a Porcine Model.

BACKGROUND: Continuous advancements and breakthroughs in flexible gastrointestinal endoscopy have led to alternatives to colonic anastomosis. OBJECTIVE: This study aimed to evaluate the feasibility and safety of end-to-end colonic anastomosis using a single flexible endoscope with the novel through-the-scope "bow-tie" (TTS-BT) device and conventional metal clips in a porcine model. DESIGN: Animal study. SETTINGS: Animal laboratory at China Medical University. PATIENTS: Eight healthy pigs were included. INTERVENTIONS: Eight animals underwent total colonic severance and anastomoses with through-the-scope "bow-tie" devices and metal clips. MAIN OUTCOME MEASURES: The primary outcomes were the success rate of the anastomosis and survival rate during 3-month follow-up. Furthermore, the secondary outcomes were anastomotic site healing, reintervention rate, and rate of anastomotic complications such as bleeding, leakage, stenosis, and obstruction. Six pigs were euthanized, and necropsies were performed 3 months postoperatively, while two pigs were fed for long-term observation. The anastomotic stoma was histologically analyzed using Hematoxylin-eosin and Masson's trichrome staining. RESULTS: End-to-end colonic anastomoses were successfully performed using through-the-scope "bow-tie" devices, and satisfactory healing was achieved in all pigs. The success rate of anastomosis was 100% (8/8). All animals survived postoperatively without anastomotic complications, including bleeding, leakage, or obstruction; however, two cases of stenosis occurred (25%), and one case (12.5%) required reintervention. LIMITATIONS: Large-scale studies should be conducted to verify the feasibility and safety of the through-the-scope "bow-tie" device in other parts of the intestine. CONCLUSIONS: Flexible endoscopy with the through-the-scope "bow-tie" device is feasible and safe for intraluminal colonic anastomosis. This study may expand the indications for full-thickness endoscopic resection in the future. See Video abstract.

Fluorescence molecular tomography based on an online maximum a posteriori estimation algorithm.

Fluorescence molecular tomography (FMT) is a non-invasive, radiation-free, and highly sensitive optical molecular imaging technique for early tumor detection. However, inadequate measurement information along with significant scattering of near-infrared light within the tissue leads to high ill-posedness in the inverse problem of FMT. To improve the quality and efficiency of FMT reconstruction, we build a reconstruction model based on log-sum regularization and introduce an online maximum a posteriori estimation (OPE) algorithm to solve the non-convex optimization problem. The OPE algorithm approximates a stationary point by evaluating the gradient of the objective function at each iteration, and its notable strength lies in the remarkable speed of convergence. The results of simulations and experiments demonstrate that the OPE algorithm ensures good reconstruction quality and exhibits outstanding performance in terms of reconstruction efficiency.

Corneal densitometry in Chinese adults with healthy corneas: associations with sex, age, ocular metrics, and optical characteristics.

BACKGROUND: Standardized corneal densitometry (CD) values in large samples of healthy Chinese individuals are scarce. Therefore, we aimed to determine the standard CD values using a Scheimpflug camera in healthy corneas, investigate the correlations of sex, age, and ocular parameters with corneal density, and explore the impact of corneal density on the forward scattering and optical quality of the eye. METHODS: This retrospective observational study involved 990 healthy Chinese individuals, including 494 males and 496 females (mean age: 23.88 ± 6.90 years). The CD values at various depths and radial areas of 0-12 mm were measured using a Scheimpflug camera. Densitometric measurements were expressed in standardized grayscale units (GSU). The optical scatter index (OSI), modulation transfer function cutoff values (MTFcutoff), and Strehl's ratio (SR) were also determined using an optical quality analysis system. RESULTS: The average CD within a 12 mm diameter area was 16.26 ± 1.35 GSU. The highest and lowest optical densities at different depths were observed in the anterior (21.41 ± 2.16 GSU) and posterior (12.00 ± 1.01 GSU) layers, respectively (P < 0.001). Similarly, the maximum and minimum optical densities at different radial areas were observed in the 10-12 mm (14.09 ± 0.93 GSU) and 2-6 mm (25.93 ± 4.77 GSU) circles, respectively (P < 0.001). There was no significant difference in the average CD within a 12 mm diameter area between males and females (P > 0.05). However, upon adjusting for age, central corneal thickness (CCT), corneal curvature, white-to-white (WTW) corneal diameter, and axial length, females exhibited a greater average CD within the 12 mm diameter and in the 6-10 mm and 10-12 mm circles than males. Age-related changes in CD were evident, except in the 2-6 mm circle. CCT, corneal curvature, WTW corneal diameter, and partial depth correlated with CD in the radial area, and CD in different areas correlated with the OSI, MTFcutoff, and SR (P < 0.05). CONCLUSIONS: This study provides the normative CD measurement data of Chinese adults with healthy corneas, emphasizing the significance of sex, age, CCT, corneal curvature, and WTW corneal diameter in CD evaluation. Notably, elevated CD can lead to increased forward scattering within the eye, thereby affecting the optical quality.

Associations between type 2 diabetes mellitus and risk of falls among community-dwelling elderly people in Guangzhou, China: a prospective cohort study.

BACKGROUND: Several studies have demonstrated that older adults with type 2 diabetes mellitus (T2DM) have a higher risk of falls compared to those without T2DM, which may lead to disability and a lower quality of life. While, limited prospective studies have quantified the associations in southern China. We conducted a longitudinal cohort study to quantify the associations between T2DM and falls and investigate the risk factors of falls among community-dwelling elderly people in Guangzhou, China. METHODS: The population-based study included 8800 residents aged 65 and over in 11 counties of Guangzhou at baseline in 2020 and then prospectively followed up through 2022. Of 6169 participants had complete follow-up and were included in the present study. A fall event was identified by self-reported. The Cox regression was applied to quantify the associations between T2DM and falls, and hazard ratios (HRs) were calculated to the factors associated with falls among participants. RESULTS: The median follow-up time for participants was 2.42 years. During the follow-up period, the incidence of falls among all participants was 21.96%. After adjusting for covariates in Cox regression models, T2DM remained a significant risk factor for falls, with HR of 1.781 (95% CI: 1.600-1.983) in the unadjusted covariates model and 1.757 (1.577-1.957) in the adjusted covariates model. Female (1.286, 1.136-1.457), older age (≥ 80: 1.448, 1.214-1.729), single marital status (1.239, 1.039-1.477), lower education level (primary school and below: 1.619, 1.004-1.361), hypertension (1.149, 1.026-1.286) and stroke (1.619, 1.176-2.228) were associated with a higher risk of falls, whereas everyday physical exercise (0.793, 0.686-0.918) was associated with a lower risk of falls. CONCLUSION: Falls are common, with risks between T2DM and falls quantified and several factors investigated in the longitudinal cohort study among community-dwelling elderly people in Guangzhou, China. Targeted action on the risk factors may reduce the burden of falls in elderly people with T2DM in the future.

Association between abdominal obesity indices and falls among older community-dwellers in Guangzhou, China: a prospective cohort study.

BACKGROUND: Central obesity was considered as a risk factor for falls among the older population. Waist circumference (WC), lipid accumulation product (LAP), visceral adiposity index (VAI), and the Chinese visceral adiposity index (CVAI) are considered as surrogate markers for abdominal fat deposition in increasing studies. Nevertheless, the longitudinal relationship between these indices and falls among the older population remains indistinct. This study aimed to explore the association between abdominal obesity indices and falls among older community-dwellers. METHODS: Our study included 3501 individuals aged ≥ 65 years from the Guangzhou Falls and Health Status Tracking Cohort at baseline in 2021 and then prospectively followed up in 2022. The outcome of interest was the occurrence of falls. The Kaplan-Meier curves and multivariable Cox regression analysis were used to explore the associations between abdominal obesity indices and falls. Moreover, the restricted cubic spline analysis (RCS) was conducted to test the non-linear relationships between abdominal obesity indices and hazards of falls incident. RESULTS: After a median follow-up period of 551 days, a total of 1022 participants experienced falls. The cumulative incidence rate of falls was observed to be higher among individuals with central obesity and those falling within the fourth quartile (Q4) of LAP, VAI, and CVAI. Participants with central obesity and those in Q4 of LAP, VAI, and CVAI were associated with higher risk of falls, with hazard ratios (HRs) of 1.422 (HR 95%CI: 1.255-1.611), 1.346 (1.176-1.541), 1.270 (1.108-1.457), 1.322 (1.154-1.514), respectively. Each 1-SD increment in WC, LAP, VAI, and CVAI was a significant increased risk of falls among participants. Subgroup analysis further revealed these results were basically stable and appeared to be significantly stronger among those females, aged 65-69 years, and with body mass index (BMI) ≥ 28 kg/m2. Additionally, RCS curves showed an overall upward trend in the risk of falls as the abdominal indices increased. CONCLUSIONS: Abdominal obesity indices, as WC, LAP, VAI, and CVAI were significantly associated with falls among older community-dwellers. Reduction of abdominal obesity indices might be suggested as the strategy of falls prevention.

Efficacy and Safety of Corticosteroid in Combination with 5-Fluorouracil in the Treatment of Keloids and Hypertrophic Scars: A Systematic Review and Meta-analysis.

BACKGROUND: Addressing hypertrophic scars and keloids poses a significant challenge in the realm of preventive and curative medicine. Combination corticosteroid with 5-fluorouracil (5-FU) is presumed to enhance the treatment of hypertrophic scars and keloids, although supportive evidence is lacking. This study is aimed at comparing the efficacy and safety profile of a combined corticosteroid and 5-FU regimen in treating hypertrophic scars and keloids. METHODS: A comprehensive search was conducted for pertinent studies across various databases, including Web of Science, PubMed, Google Scholar, Cochrane Library, and Medline. The calculation of weighted mean difference (WMD), risk ratios (RR), odds ratios (OR), and 95% confidence intervals (CIs) was executed. Additionally, the Cochrane Collaboration's Risk of Bias Tool was utilized to evaluate potential bias risks. RESULTS: A total of 15 studies were involved. The effectiveness based on patient self-assessment and the effectiveness based on observer assessment were significantly higher in the corticosteroid+5-FU group compared to those treated with control. A meta-analysis of scar height showed that the corticosteroid+5-FU group performed better than the control group (WMD = -0.38, 95% CI -0.58 to -0.18). There was no significant difference between the corticosteroid+5-FU group and the control group in improving scar vascularity, pliability and pigmentation. The result revealed that the corticosteroid+5-FU group of patients had less adverse effect of hypopigmentation, skin atrophy and telangiectasia than the control group. CONCLUSION: The combined use of corticosteroids and 5-FU appears to be a more effective strategy for the treatment and prevention of hypertrophic scars and keloids, as evidenced by greater improvements in scar height and overall effectiveness, coupled with a reduced incidence of side effects. LEVEL OF EVIDENCE II: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Exploration the interaction of cadmium and copper toxic effects in pakchoi (Brassica chinensis L) roots through combinatorial transcriptomic and weighted gene co-expression network analysis.

The interaction between cadmium(Cd) and copper(Cu) during combined pollution can lead to more complex toxic effects on humans and plants.However, there is still a lack of sufficient understanding regarding the types of interactions at the plant molecular level and the response strategies of plants to combined pollution. To assess this, we investigated the phenotypic and transcriptomic patterns of pakchoi (Brassica chinensis L) roots in response to individual and combined pollution of Cd and Cu. The results showed that compared to single addition, the translocation factor of heavy metals in roots significantly decreased (p < 0.05) under the combined addition, resulting in higher accumulation of Cd and Cu in the roots. Transcriptomic analysis of pakchoi roots revealed that compared to single pollution, there were 312 and 1926 differentially expressed genes (DEGs) specifically regulated in the Cd2Cu20 and Cd2Cu100 combined treatments, respectively. By comparing the expression of these DEGs among different treatments, we found that the combined pollution of Cd and Cu mainly affected the transcriptome of the roots in an antagonistic manner. Enrichment analysis indicated that pakchoi roots upregulated the expression of genes involved in glucosetransferase activity, phospholipid homeostasis, proton transport, and the biosynthesis of phenylpropanoids and flavonoids to resist Cd and Cu combined pollution. Using weighted gene co-expression network analysis (WGCNA), we identified hub genes related to the accumulation of Cd and Cu in the roots, which mainly belonged to the LBD, thaumatin-like protein, ERF, MYB, WRKY, and TCP transcription factor families. This may reflect a transcription factor-driven trade-off strategy between heavy metal accumulation and growth in pakchoi roots. Additionally, compared to single metal pollution, the expression of genes related to Nramp, cation/H+ antiporters, and some belonging to the ABC transporter family in the pakchoi roots was significantly upregulated under combined pollution. This could lead to increased accumulation of Cd and Cu in the roots. These findings provide new insights into the interactions and toxic mechanisms of multiple metal combined pollution at the molecular level in plants.

The effect of neoadjuvant chemotherapy on surgical site wound infection after immediate breast reconstruction in patients with breast cancer: A meta-analysis.

Using a meta-analysis approach, we conducted a comprehensive evaluation of the effect of neoadjuvant chemotherapy (NACT) on the incidence of surgical site wound infection during immediate breast reconstruction (IBR) following breast cancer. The aim was to provide evidence-based support for the prevention of wound surgical site infection during IBR after breast cancer surgery. Relevant literature on the effects of NACT on IBR in patients with breast cancer published up until May 2023, was retrieved from various databases, including PubMed, Cochrane Library, EMBASE, China National Knowledge Infrastructure (CNKI), Wanfang databases, and China Biology Medicine Database. Two researchers performed the literature screening, data collection, and quality assessment of the included studies independently. The meta-analysis was conducted using Stata version 17.0. Fourteen studies involving 3401 patients (599 in the intervention group and 2802 in the control group) were included in the analysis. The incidence of surgical site infection in the NACT group was higher than that in the control group, but the difference between the two groups was not statistically significant (7.17% vs. 4.85%, odds ratio: 1.02, 95% confidence interval: 0.70-1.50, p = 0.902). These findings suggest that NACT does not increase the risk of surgical site infection during IBR. However, owing to the variation in sample size and literature quality among the included studies, randomised controlled trials are needed to confirm the safety of IBR in patients receiving neoadjuvant chemotherapy.