Forward and Inverse Energy Cascade in Fluid Turbulence Adhere to Kolmogorov's Refined Similarity Hypothesis.

We study fluctuations of the local energy cascade rate Φ_{ℓ} in turbulent flows at scales (ℓ) in the inertial range. According to the Kolmogorov refined similarity hypothesis (KRSH), relevant statistical properties of Φ_{ℓ} should depend on ε_{ℓ}, the viscous dissipation rate locally averaged over a sphere of size ℓ, rather than on the global average dissipation. However, the validity of KRSH applied to Φ_{ℓ} has not yet been tested from data. Conditional averages such as ⟨Φ_{ℓ}|ε_{ℓ}⟩ as well as of higher-order moments are measured from direct numerical simulations data, and results clearly adhere to the predictions from KRSH. Remarkably, the same is true when considering forward (Φ_{ℓ}>0) and inverse (Φ_{ℓ}<0) cascade events separately. Measured ratios of forward and inverse cascade probability densities conditioned on ε_{ℓ} also confirm the applicability of the KRSH to analysis of the fluctuation relation from nonequilibrium thermodynamics.

[Effect of HCMV infection on immune reconstitution of CD8+T cells in children with allogeneic hematopoietic stem cell transplantation].

Objective: To investigate the risk factors for human cytomegalovirus infection after allogeneic hematopoietic stem cell transplantation in children and the impact of human cytomegalovirus infection on post-transplant immune reconstitution. Methods: A Retrospective Co-Hort study design was used to include 81 children treated with allo-HSCT from January 2020 to March 2022 at the Department of Hematology, Capital Institute of Pediatrics, Beijing, China, and followed up for 1 year. Real-time quantitative PCR was used to detect positive detection of HCMV in children after allo-HSCT, multifactorial logistic regression modeling was used to analyze the risk factors leading to HCMV infection, and generalized estimating equation modeling was used to analyze the effect of HCMV infection on the T-cells of the children who received allo-HSCT. Results: The age M(Q1, Q3) of 81 children was 5.1 years (10 months, 13.8 years), and 50 (61.7%) were male. By the endpoint of follow-up, a total of 50 HCMV-positive cases were detected, with an HCMV detection rate of 61.7%; The results of multifactorial logistic regression modeling showed that children with grade 2-4 aGVHD had a higher risk of HCMV infection compared with grade 0-1 after transplantation [OR (95%CI) value: 2.735 (1.027-7.286)]. The results of generalized estimating equation modeling analysis showed that the number of CD3+T cells in HCMV-positive children after transplantation was higher than that in the HCMV-negative group [RR (95%CI) value: 1.34 (1.008-1.795)]; the ratio of CD4+T/CD8+T cells was smaller than that in the HCMV-negative group [RR (95%CI) value: 0.377 (0.202-0.704)]; the number of CD8+T cells was higher than that in the HCMV-negative group [RR (95%CI) value: 1.435 (1.025-2.061)]; the number of effector memory CD8+T cells was higher than that in the HCMV-negative group [RR (95%CI) value: 1.877 (1.089-3.236)]. Conclusion: Acute graft-versus-host disease may be a risk factor for HCMV infection in children after allo-HSCT; post-transplant HCMV infection promotes proliferation of memory CD8+T-cell populations and affects immune cell reconstitution.

Effect of pneumatic leg compression on phenylephrine dose for hypotension prophylaxis via variable rate infusion at cesarean delivery: an unblinded randomized controlled trial.

BACKGROUND: Phenylephrine infusion is recommended to prevent spinal hypotension during cesarean delivery (CD) but may be associated with dose-dependent side effects. We hypothesized that adding intermittent pneumatic compression (IPC) of the lower legs to a variable-rate phenylephrine infusion will reduce the dose of phenylephrine required during CD. METHODS: Seventy-six healthy women undergoing elective CD under combined spinal-epidural anesthesia were randomly assigned to IPC or control groups (n = 38 per group). After spinal anesthesia, IPC of the lower legs was initiated in the IPC group, and all women received a phenylephrine infusion starting at 25 µg·min-1 and increasing by 16.7 µg·min-1 for systolic blood pressure (SAP) < 90% baseline. If hypotension (SAP < 80% baseline) occurred, 100 µg phenylephrine bolus was administered. The primary outcome was the dose of phenylephrine per minute. RESULTS: The dose of phenylephrine per minute (34.4 ±â€¯7.3 µg·min-1 vs. 40.9 ±â€¯9.5 µg·min-1, P = 0.001; mean difference -6.6 µg·min-1, 95% CI -10.5 to -2.7 µg·min-1) and the incidence of hypotension (24% vs. 55%, P = 0.005) were lower in the IPC group than in the control group. There were no significant differences between the two groups in the total dose of phenylephrine (603.2 ±â€¯217.1 µg vs. 706.2 ±â€¯247.5 µg, P = 0.058; mean difference -102.9 µg, 95% CI -209.4 to 3.5 µg), maternal side effects, or neonatal outcomes. CONCLUSIONS: Intermittent pneumatic compression combined with a variable-rate phenylephrine infusion reduced the phenylephrine dose per minute and the incidence of hypotension during CD under spinal anesthesia.

Comparison of survival between palliative surgery and no surgery for advanced tongue squamous cell carcinoma: an analysis of SEER data.

The aim of this study was to investigate the survival effect of palliative surgery in advanced tongue squamous cell carcinoma (TSCC). A retrospective analysis of data in the SEER database for 6151 patients with stage III/IV TSCC (American Joint Committee on Cancer (AJCC) staging), diagnosed between 2004 and 2015, was performed. The patients were divided into two groups: palliative surgery and no surgery. Kaplan-Meier and Cox proportional hazards regression analyses were applied to determine risk factors for overall survival (OS) and cancer-specific survival (CSS). A further analysis was performed using 1:1 propensity score matching (PSM) to balance 13 patient variables (sex, age at diagnosis, race, marital status, primary tumour site, SEER stage, AJCC stage, pathological differentiation grade, tumour size, lymph node metastasis, previous lymph node removal, radiotherapy, and chemotherapy). Among the 6151 patients, 706 underwent palliative surgery; the other 5445 did not undergo any kind of surgery. Those who underwent palliative surgery had a higher 5-year survival rate. After PSM, 1274 patients were included in the matched cohort. Multivariate Cox regression analysis showed that patients who underwent palliative surgery had a lower risk of death than those who did not (OS: hazard ratio 0.58, 95% confidence interval 0.49-0.69, P < 0.001; CSS: hazard ratio 0.60, 95% confidence interval 0.49-0.74, P < 0.001). In this comparative study it was found that compared with no surgery, palliative surgery has a positive impact on the survival rate of patients with advanced TSCC.

Effects of different mesh materials on complications after prophylactic placement for stoma formation: a systematic review and network meta-analysis.

PURPOSE: We primary aimed to synthesise the available data, assess the effectiveness of different mesh materials in prophylactic mesh placement, and rank these materials according to the incidence of parastomal hernia (PSH) and other stoma complications. METHOD: This network meta-analysis performed a systematic review and meta-analysis according to the Preferred Reporting Items for Systematic Review and Meta-Analysis statement. Four databases were searched for randomised controlled trials of prophylactic mesh placement. The aggregated results were performed in the STATA routine for Bayesian hierarchical random effects models. RESULT: Thirteen randomised controlled trials from 1203 articles, met the inclusion criteria, including 681 cases without meshes, 65 cases with mesh material of xenogeneic acellular dermis (porcine/bovine), 27 cases with polypropylene/PG910, 114 cases with polypropylene/polyglecaprone (Monocryl), 117 cases with polypropylene/cellulose (ORC), 233 cases with polypropylene, and 35 cases with polypropylene/PVDF. In network A, compared with no mesh, only polypropylene (RR 0.24, 95% CI 0.04-0.80) were significantly associated with a reduction in the incidence of PSH. In network B, no statistical difference regarding stoma complications was found between mesh and no mesh. CONCLUSION: Based on the network meta-analysis and ranking results, the polypropylene mesh material exhibited the best performance. However, this conclusion needs to be confirmed with larger sample sizes and high-quality randomised controlled trials.

[Construction of a model based on multipoint full-layer puncture biopsy for predicting pathological complete response after neoadjuvant therapy for locally advanced rectal cancer].

Objective: To investigate the value of transanal multipoint full-layer puncture biopsy (TMFP) in predicting pathological complete response (pCR) after neoadjuvant radiotherapy and chemotherapy (nCRT) in patients with locally advanced rectal cancer (LARC) and to establish a predictive model for providing clinical guidance regarding the treatment of LARC. Methods: In this multicenter, prospective, cohort study, we collected data on 110 LARC patients from four hospitals between April 2020 and March 2023: Beijing Chaoyang Hospital of Capital Medical University (50 patients), Beijing Friendship Hospital of Capital Medical University (41 patients), Qilu Hospital of Shandong University (16 patients), and Zhongnan Hospital of Wuhan University (three patients). The patients had all received TMFP after completing standard nCRT. The variables studied included (1) clinicopathological characteristics; (2) clinical complete remission (cCR) and efficacy of TMFP in determining pCR after NCRT in LARC patients; and (3) hospital attended, sex, age, clinical T- and N-stages, distance between the lower margin of the tumor and the anal verge, baseline and post-radiotherapy serum carcinoembryonic antigen (CEA) and carbohydrate antigen (CA)19-9 concentrations, chemotherapy regimen, use of immunosuppressants with or without radiotherapy, radiation therapy dosage, interval between surgery and radiotherapy, surgical procedure, clinical T/N stage after radiotherapy, cCR, pathological results of TMFP, puncture method (endoscopic or percutaneous), and number and timing of punctures. Single-factor and multifactorial logistic regression analysis were used to determine the factors affecting pCR after NCRT in LARC patients. A prediction model was constructed based on the results of multivariat analysis and the performance of this model evaluated by analyzing subject work characteristics (ROC), calibration, and clinical decision-making (DCA) curves. pCR was defined as complete absence of tumor cells on microscopic examination of the surgical specimens of rectal cancer (including lymph node dissection) after NCRT, that is, ypT0+N0. cCR was defined according to the Chinese Neoadjuvant Rectal Cancer Waiting Watch Database Study Collaborative Group criteria after treatment, which specify an absence of ulceration and nodules on endoscopy; negative rectal palpation; no tumor signals on rectal MRI T2 and DWI sequences; normal serum CEA concentrations, and no evidence of recurrence on pelvic computed tomography/magnetic resonance imaging. Results: Of the 110 patients, 45 (40.9%) achieved pCR after nCRT, which was combined with immune checkpoint inhibitors in 34 (30.9%). cCR was diagnosed before puncture in 38 (34.5%) patients, 43 (39.1%) of the punctures being endoscopic. There were no complications of puncture such as enterocutaneous fistulae, vaginal injury, prostatic injury, or presacral bleeding . Only one (2.3%) patient had a small amount of blood in the stools, which was relieved by anal pressure. cCR had a sensitivity of 57.8% (26/45) for determining pCR, specificity of 81.5% (53/65), accuracy of 71.8% (79/110), positive predictive value 68.4% (26/38), and negative predictive value of 73.6% (53/72). In contrast, the sensitivity of TMFP pathology in determining pCR was 100% (45/45), specificity 66.2% (43/65), accuracy 80.0% (88/110), positive predictive value 67.2% (45/67), and negative predictive value 100.0% (43/43). In this study, the sensitivity of TMFP for pCR (100.0% vs. 57.8%, χ2=24.09, P<0.001) was significantly higher than that for cCR. However, the accuracy of pCR did not differ significantly (80.0% vs. 71.8%, χ2=2.01, P=0.156). Univariate and multivariate logistic regression analyses showed that a ≥4 cm distance between the lower edge of the tumor and the anal verge (OR=7.84, 95%CI: 1.48-41.45, P=0.015), non-cCR (OR=4.81, 95%CI: 1.39-16.69, P=0.013), and pathological diagnosis by TMFP (OR=114.29, the 95%CI: 11.07-1180.28, P<0.001) were risk factors for pCR after NCRT in LARC patients. Additionally, endoscopic puncture (OR=0.02, 95%CI: 0.05-0.77, P=0.020) was a protective factor for pCR after NCRT in LARC patients. The area under the ROC curve of the established prediction model was 0.934 (95%CI: 0.892-0.977), suggesting that the model has good discrimination. The calibration curve was relatively close to the ideal 45° reference line, indicating that the predicted values of the model were in good agreement with the actual values. A decision-making curve showed that the model had a good net clinical benefit. Conclusion: Our predictive model, which incorporates TMFP, has considerable accuracy in predicting pCR after nCRT in patients with locally advanced rectal cancer. This may provide a basis for more precisely selecting individualized therapy.

Biological significance of miR-126 expression in atrial fibrillation and heart failure

We investigated the biological significance of microRNA-126 (miR-126) expression in patients with atrial fibrillation (AF) and/or heart failure (HF) to examine the possible mechanism of miR-126-dependent AF and development of HF. A total of 103 patients were divided into three groups: AF group (18 men and 17 women, mean age: 65.62±12.72 years), HF group (17 men and 15 women, mean age: 63.95±19.71 years), and HF-AF group (20 men and 16 women, mean age: 66.56±14.37 years). Quantitative real-time PCR was used to measure relative miR-126 expression as calculated by the 2−ΔΔCt method. miR-126 was frequently downregulated in the 3 patient groups compared with controls. This reduction was significantly lower in permanent and persistent AF patients than in those with paroxysmal AF (P<0.05, t-test). Moreover, miR-126 expression was markedly lower in the HF-AF group compared with the AF and HF groups. The 3 patient groups had higher N-terminal prohormone brain natriuretic peptide (NT-proBNP) levels, lower left ventricular ejection fraction (LVEF), larger left atrial diameter, and higher cardiothoracic ratio compared with controls. There were significant differences in NT-proBNP levels and LVEF among the AF, HF, and HF-AF groups. Pearson correlation analysis showed that relative miR-126 expression was positively associated with LVEF, logarithm of NT-proBNP, left atrial diameter, cardiothoracic ratio, and age in HF-AF patients. Multiple linear regression analysis showed that miR-126 expression was positively correlated with LVEF, but negatively correlated with the logarithm of NT-pro BNP and the cardiothoracic ratio (all P<0.05). Serum miR-126 levels could serve as a potential candidate biomarker for evaluating the severity of AF and HF. However, to confirm these results, future studies with a larger and diverse patient population are necessary.