Multicentre validation of a machine learning model for predicting respiratory failure after noncardiac surgery.

BACKGROUND: Postoperative respiratory failure is a serious complication that could benefit from early accurate identification of high-risk patients. We developed and validated a machine learning model to predict postoperative respiratory failure, defined as prolonged (>48 h) mechanical ventilation or reintubation after surgery. METHODS: Easily extractable electronic health record (EHR) variables that do not require subjective assessment by clinicians were used. From EHR data of 307,333 noncardiac surgical cases, the model, trained with a gradient boosting algorithm, utilised a derivation cohort of 99,025 cases from Seoul National University Hospital (2013-9). External validation was performed using three separate cohorts A-C from different hospitals comprising 208,308 cases. Model performance was assessed by area under the receiver operating characteristic (AUROC) curve and area under the precision-recall curve (AUPRC), a measure of sensitivity and precision at different thresholds. RESULTS: The model included eight variables: serum albumin, age, duration of anaesthesia, serum glucose, prothrombin time, serum creatinine, white blood cell count, and body mass index. Internally, the model achieved an AUROC of 0.912 (95% confidence interval [CI], 0.908-0.915) and AUPRC of 0.113. In external validation cohorts A, B, and C, the model achieved AUROCs of 0.879 (95% CI, 0.876-0.882), 0.872 (95% CI, 0.870-0.874), and 0.931 (95% CI, 0.925-0.936), and AUPRCs of 0.029, 0.083, and 0.124, respectively. CONCLUSIONS: Utilising just eight easily extractable variables, this machine learning model demonstrated excellent discrimination in both internal and external validation for predicting postoperative respiratory failure. The model enables personalised risk stratification and facilitates data-driven clinical decision-making.

The Impact and Implications of the Flexner Report on Medical Education in Korea.

The recent debate surrounding the expansion of enrollment in Korean medical schools has reignited interest in the Flexner Report, published in the United States in 1910. Historically, medical education in the United States transitioned from small proprietary schools to university-affiliated institutions, emphasizing basic science and clinical experience. The Flexner Report advocated for scientific medicine and led to significant reforms in medical education, including standardization of curricula and strengthened admission requirements. The influence of this report extended to Korean medical education, shaping its curriculum, accreditation system, and emphasis on academic excellence. The expansion of medical school enrollment has led to a crucial dilemma. Should we prioritize the training of physicians who provide practical medical services or continue to emphasize academic medicine as we do now? There has been insufficient discussion of the individualized curricula, necessary investments, and societal efforts to accommodate these changes. It is imperative to move beyond mere enrollment expansion debates and collectively determine the future trajectory of Korean medical education, devising actionable plans to achieve overarching goals.

COVID-19 vaccination-related myocarditis: a Korean nationwide study.

AIMS: A comprehensive nationwide study on the incidence and outcomes of COVID-19 vaccination-related myocarditis (VRM) is in need. METHODS AND RESULTS: Among 44 276 704 individuals with at least 1 dose of COVID-19 vaccination, the incidence and clinical courses of VRM cases confirmed by the Expert Adjudication Committee of the Korea Disease Control and Prevention Agency were analyzed. COVID-19 VRM was confirmed in 480 cases (1.08 cases per 100 000 persons). Vaccination-related myocarditis incidence was significantly higher in men than in women (1.35 vs. 0.82 per 100 000 persons, P < 0.001) and in mRNA vaccines than in other vaccines (1.46 vs. 0.14 per 100 000 persons, P < 0.001). Vaccination-related myocarditis incidence was highest in males between the ages of 12 and 17 years (5.29 cases per 100 000 persons) and lowest in females over 70 years (0.16 cases per 100 000 persons). Severe VRM was identified in 95 cases (19.8% of total VRM, 0.22 per 100 000 vaccinated persons), 85 intensive care unit admission (17.7%), 36 fulminant myocarditis (7.5%), 21 extracorporeal membrane oxygenation therapy (4.4%), 21 deaths (4.4%), and 1 heart transplantation (0.2%). Eight out of 21 deaths were sudden cardiac death (SCD) attributable to VRM proved by an autopsy, and all cases of SCD attributable to VRM were aged under 45 years and received mRNA vaccines. CONCLUSION: Although COVID-19 VRM was rare and showed relatively favorable clinical courses, severe VRM was found in 19.8% of all VRM cases. Moreover, SCD should be closely monitored as a potentially fatal complication of COVID-19 vaccination.

Increased cholesterol uptake is associated with the altered gene expression in white adipose tissue of ApoE-/- mice fed a high-fat high-cholesterol diet.

Apolipoprotein E knock out (ApoE-/-) mice, the widely used model for atherosclerosis, exhibits anti-obesity characteristics due to the impaired lipoprotein internalization. Since excessive accumulation of triglycerides and cholesterol in white adipose tissue (WAT) is shown to increase the risk of metabolic diseases, we investigated the effects of dietary high-fat high-cholesterol (HFHC) on gene expression profile and the possible role of cholesterol accumulation in WAT of ApoE-/- mice. Control (CON) and HFHC diets were provided to wild-type mice (WC, WH) and ApoE-/- mice (EC, EH) for 10 weeks. Although body and WAT weights were lower in the ApoE-/- group compared to the wild-type group, increases in cholesterol and lipid peroxides in WAT were only observed in the ApoE-/- group. Transcriptome analysis revealed 3660 and 839 differentially expressed genes (DEGs) in the EC/WC and EH/WH comparison, respectively. "Thermogenesis" and "Oxidative phosphorylation" KEGG pathways were found in the EC/WC comparison, but not in the EH/WH comparison. We identified 142 and 2585 DEGs in the WH/WC and EH/EC comparison respectively, indicating a stronger effect of HFHC on WAT of ApoE-/- mice. Gene ontology analysis of DEGs revealed the association of DEGs with "Regulation of inflammatory response" term, in the EH/EC comparison, but not in the WH/WC comparison. Especially, genes encoding scavenger receptors and toll-like receptors were associated with cholesterol and lipid peroxide levels in WAT of ApoE-/- mice, but not in wild-type mice. In conclusion, changes in gene expression profile of WAT were more pronounced in ApoE-/- mice compared to wild-type mice in response to HFHC, and these altered genes were related to inflammatory response. These data suggest that increased cholesterol accumulation in WAT by dietary HFHC may play a pivotal role in the regulation of gene expression in ApoE-/- mice.

Balloon-occluded transarterial chemoembolization versus conventional transarterial chemoembolization for the treatment of single hepatocellular carcinoma: a propensity score matching analysis.

OBJECTIVES: To compare the safety and efficacy of balloon-occluded transarterial chemoembolization (B-TACE) and conventional TACE (C-TACE) in treating single hepatocellular carcinoma (HCC). METHODS: This single-center retrospective study included 523 patients who underwent C-TACE and 44 who underwent B-TACE as first-line treatment for single HCCs between November 2017 and December 2019. After propensity score matching (PSM), initial tumor response rates, local tumor progression (LTP), and major complication rates were evaluated in the 32 pairs of PSM matched population. RESULTS: In the 32 pairs of PSM cohort, B-TACE showed distinct superiority over C-TACE in treating single HCCs, with significantly higher initial complete response (CR) rates (93.8% vs. 62.5%, p = 0.005). During a median follow-up of 37 months (range, 12.7-46.5 months), 13 patients (40.6%) who underwent B-TACE and 16 (50%) who underwent C-TACE showed LTP of treated lesions. Size-based sub-group analysis showed that the median times to LTP in patients with medium- to large-sized tumors (> 3 cm) were significantly longer in the B-TACE (27 months; 95% confidence interval [CI], 19.7-34.3 months) than in the C-TACE (13 months; 95% CI, 3.9-22.1 months) group (p = 0.019). The major complication rate was similar between the two groups. CONCLUSIONS: B-TACE had a higher initial CR rate than C-TACE in treating single HCCs. Moreover, size-based subgroup analysis showed that time to LTP was significantly longer in patients with medium- to large-sized HCCs (> 3 cm) who underwent B-TACE rather than C-TACE. KEY POINTS: • B-TACE was superior to C-TACE in treating single HCC, with a significantly higher initial complete response rate after one session of treatment. • In size-based subgroup analysis, time to LTP was significantly longer in patients with medium- to large-sized HCCs (>3 cm) who underwent B-TACE rather than C-TACE. • B-TACE should be considered an alternative treatment option for medium- to large-sized single HCCs (>3 cm) in patients with a nonresectable condition and those who prefer nonsurgical treatment.

Intermediate-stage (BCLC stage B) infiltrative hepatocellular carcinoma: safety and efficacy of chemoembolization.

OBJECTIVES: To evaluate the safety and efficacy of chemoembolization in patients with intermediate-stage infiltrative Hepatocellular carcinoma (HCC). MATERIALS AND METHODS: This retrospective study evaluated outcomes in treatment-naïve patients who received chemoembolization as first-line treatment for intermediate-stage infiltrative HCC between 2002 and 2022. Of the 2029 treatment-naïve patients who received chemoembolization as first-line treatment for intermediate-stage HCC, 244 (12%) were identified as having the infiltrative type. After excluding two patients lost to follow-up, 242 patients were evaluated. RESULTS: Median post-chemoembolization overall survival (OS) was 16 months. Multivariable Cox analysis identified four factors predictive of OS: Child-Pugh class B (hazard ratio [HR], 1.84; p = 0.001), maximal tumor size ≥ 10 cm (HR, 1.67; p < 0.001), tumor number ≥ 4 (HR, 1.42; p = 0.037), and bilobar tumor involvement (HR, 1.64; p = 0.003). These four factors were used to create pretreatment prediction models, with risk scores of 0-1, 2-4, and 5-7 defined as low, intermediate, and high risk, respectively. Median OS times in these three groups were 34, 18, and 8 months, respectively (p < 0.001). The objective tumor response rate following chemoembolization was 53%. The major complication rate was 9% overall and was significantly higher in the high-risk group (22%) than in the low (2%) and intermediate (3%) risk groups (p < 0.001). CONCLUSION: Chemoembolization is safe and effective in selected patients with intermediate-stage infiltrative HCC. Chemoembolization is not recommended in high-risk patients with intermediate-stage infiltrative HCC because of poor OS and high rates of major complications. CLINICAL RELEVANCE STATEMENT: A pretreatment prediction model was developed using four risk factors associated with overall survival following chemoembolization for intermediate-stage infiltrative hepatocellular carcinoma. This model may provide valuable information for clinical decision-making. KEY POINTS: • Four risk factors (Child-Pugh score B, maximal tumor size ≥ 10 cm, tumor number ≥ 4, and bilobar tumor involvement) were used to create pretreatment prediction models, with risk scores of 0-1, 2-4, and 5-7 defined as low, intermediate, and high risk, respectively. • Median overall survival (OS) times and major complication rate in these three groups were 34, 18, and 8 months, and 2%, 3%, and 22%, respectively (p < 0.001). Chemoembolization is not recommended in high-risk patients with intermediate-stage infiltrative Hepatocellular carcinoma (HCC) because of poor OS and high rates of major complications.

Biotrickling Filtration for the Reduction of N2O Emitted during Wastewater Treatment: Results from a Long-Term In Situ Pilot-Scale Testing.

Wastewater treatment plants (WWTPs) are a major source of N2O, a potent greenhouse gas with 300 times higher global warming potential than CO2. Several approaches have been proposed for mitigation of N2O emissions from WWTPs and have shown promising yet only site-specific results. Here, self-sustaining biotrickling filtration, an end-of-the-pipe treatment technology, was tested in situ at a full-scale WWTP under realistic operational conditions. Temporally varying untreated wastewater was used as trickling medium, and no temperature control was applied. The off-gas from the covered WWTP aerated section was conveyed through the pilot-scale reactor, and an average removal efficiency of 57.9 ± 29.1% was achieved during 165 days of operation despite the generally low and largely fluctuating influent N2O concentrations (ranging between 4.8 and 96.4 ppmv). For the following 60-day period, the continuously operated reactor system removed 43.0 ± 21.2% of the periodically augmented N2O, exhibiting elimination capacities as high as 5.25 g N2O m-3·h-1. Additionally, the bench-scale experiments performed abreast corroborated the resilience of the system to short-term N2O starvations. Our results corroborate the feasibility of biotrickling filtration for mitigating N2O emitted from WWTPs and demonstrate its robustness toward suboptimal field operating conditions and N2O starvation, as also supported by analyses of the microbial compositions and nosZ gene profiles.

Effect of driving pressure-guided positive end-expiratory pressure on postoperative pulmonary complications in patients undergoing laparoscopic or robotic surgery: a randomised controlled trial.

BACKGROUND: Individualised positive end-expiratory pressure (PEEP) improves respiratory mechanics. However, whether PEEP reduces postoperative pulmonary complications (PPCs) remains unclear. We investigated whether driving pressure-guided PEEP reduces PPCs after laparoscopic/robotic abdominal surgery. METHODS: This single-centre, randomised controlled trial enrolled patients at risk for PPCs undergoing laparoscopic or robotic lower abdominal surgery. The individualised group received driving pressure-guided PEEP, whereas the comparator group received 5 cm H2O fixed PEEP during surgery. Both groups received a tidal volume of 8 ml kg-1 ideal body weight. The primary outcome analysed per protocol was a composite of pulmonary complications (defined by pre-specified clinical and radiological criteria) within 7 postoperative days after surgery. RESULTS: Some 384 patients (median age: 67 yr [inter-quartile range: 61-73]; 66 [18%] female) were randomised. Mean (standard deviation) PEEP in patients randomised to individualised PEEP (n=178) was 13.6 cm H2O (2.1). Individualised PEEP resulted in lower mean driving pressures (14.7 cm H2O [2.6]), compared with 185 patients randomised to standard PEEP (18.4 cm H2O [3.2]; mean difference: -3.7 cm H2O [95% confidence interval (CI): -4.3 to -3.1 cm H2O]; P<0.001). There was no difference in the incidence of pulmonary complications between individualised (25/178 [14.0%]) vs standard PEEP (36/185 [19.5%]; risk ratio [95% CI], 0.72 [0.45-1.15]; P=0.215). Pulmonary complications as a result of desaturation were less frequent in patients randomised to individualised PEEP (8/178 [4.5%], compared with standard PEEP (30/185 [16.2%], risk ratio [95% CI], 0.28 [0.13-0.59]; P=0.001). CONCLUSIONS: Driving pressure-guided PEEP did not decrease the incidence of pulmonary complications within 7 days of laparoscopic or robotic lower abdominal surgery, although uncertainty remains given the lower than anticipated event rate for the primary outcome. CLINICAL TRIAL REGISTRATION: KCT0004888 (http://cris.nih.go.kr, registration date: April 6, 2020).

Temporal Changes in Demography and Genetic Diversity of Oriental Storks at the Stage of Long-Term Captive Propagation and Reintroduction Initiation.

Captive propagation and reintroduction are the major steps in the ex-situ conservation of locally extirpated endangered species in a historical region. In a species restoration project conducted in South Korea, we examined temporal changes in demographics and genetic diversity of oriental storks (Ciconia boyciana). Demographic and genetic data from 1996-2018 were analyzed for 80% of all captive and recently reintroduced individuals. Founder establishment and pair formation induced increases in population size and genetic diversity during the early stage of captive propagation. The degree of genetic diversity was found to become saturated and stable with long-term captive propagation. However, this might be a concern for future genetic diversity of both captive and reintroduced populations simultaneously due to the extraction of captive populations at the early stage of reintroduction. Our findings suggest that periodic evaluation of genetic diversity and selection for releasing individuals, using effective genetic markers, would assist in balancing the genetic diversity of the captive and reintroduced oriental storks at the early stage of reintroduction.

Dietary quality and the gut microbiome in early-stage Parkinson's disease patients.

BACKGROUND: The prevalence of Parkinson's disease (PD) has increased steadily with the increase of the elderly population. PD may influence dietary intake and quality, and the gut microbiome composition. The present study examined differences in dietary intake and quality between PD patients and controls according to sex. In addition, we assessed the gut microbiome composition. METHODS: This cross-sectional study was conducted at A Medical Center, Seoul, South Korea. PD severity, swallowing function, olfactory function, and constipation status were examined by a skilled nurse. Dietary data were collected through a semi-quantitative food frequency questionnaire. Stool samples were subjected to microbiome analysis. To examine dietary quality, the Dietary Quality Index-International (DQI-I), Healthy Eating Index (HEI), Index of Nutritional Quality (INQ), Dietary Diversity Score (DDS), and Mediterranean Diet Score (MDS) were used. An independent t-test was used to determine differences between patients and controls. A chi-square test was used to examine frequency differences. RESULTS: Dietary intake did not differ between the PD patient and control groups. Regarding dietary quality, the patients consumed more saturated fat compared to controls. Overall, the dietary differences between the groups were minor. The composition of the gut microbiome differed between PD patients and controls. Lactobacillus and Bifidobacterium genus were most abundant in PD patients. Prevotella VZCB and other Faecalibacterium were most abundant in controls. CONCLUSIONS: Our results indicated that PD patients may experience gut microbiome change even in the early stage, while nutritional needs can be met when a balanced diet including various food groups are consumed.

Association between the number of pregnancies and cardiac target organ damages: a cross-sectional analysis of data from the Korean women's chest pain registry (KoROSE).

BACKGROUND: Pregnancy increases long-term cardiovascular risk after childbirth, but the mechanisms are unclear. This study was performed to investigate the association between the number of pregnancies and several cardiac target organ damage (TOD) in middle-aged and elderly women. METHODS: Using the database of the nation-wide registry, a total of 1,137 women (mean age 63.0 ± 10.9 years) with stable chest pain undergoing invasive coronary angiography (CAG) were analyzed. Information on the number of pregnancies was obtained through a questionnaire. Obstructive coronary artery disease (CAD), left ventricular (LV) mass index (LVMI) and LV septal annular (e') velocity were assessed as indicators of cardiac TOD. RESULTS: Women with higher number of pregnancies (≥ 3) were older (66.3 ± 9.6 vs. 57.4 ± 10.7 years; P < 0.001), had more cardiovascular risk factors, and took more cardiovascular medications than those with lower number of pregnancies (< 3). In multivariable analyses, higher number of pregnancies (≥ 3) was associated with obstructive CAD (odds ratio [OR], 1.62; 95% confidence interval [CI], 1.21-2.17; P = 0.001), a higher LVMI (> 95 g/m2) (OR, 1.46; 95% CI, 1.08-1.98; P = 0.013) and a lower septal e' velocity (< 7 cm/s) (OR, 1.55; 95% CI, 1.12-2.14; P = 0.007) even after controlling for potential confounders. As the number of pregnancies increased, the prevalence of CAD and LVMI increased, and the septal e' velocity gradually decreased (P < 0.001 for each). CONCLUSIONS: In women with chest pain undergoing invasive CAG, higher number of pregnancies was associated with multiple cardiac TOD. Parity information should be checked when assessing a woman's cardiovascular risk.

The effect of goal-directed hemodynamic therapy on clinical outcomes in patients undergoing radical cystectomy: a randomized controlled trial.

BACKGROUND: This study investigated the effects of intraoperative goal-directed hemodynamic therapy (GDHT) on postoperative outcomes in patients undergoing open radical cystectomy. METHODS: This prospective, single-center, randomized controlled trial included 82 patients scheduled for open radical cystectomy between September 2018 and November 2021. The GDHT group (n = 39) received the stroke volume index- and cardiac index-based hemodynamic management using advanced hemodynamic monitoring, while the control group (n = 36) received the standard care under the discretion of attending anesthesiologists during surgery. The primary outcome was the incidence of a composite of in-hospital postoperative complications during hospital stays. RESULTS: A total of 75 patients were included in the final analysis. There was no significant difference in the incidence of in-hospital postoperative complications (28/39 [71.8%] vs. 30/36 [83.3%], risk difference [95% CI], -0.12 [-0.30 to 0.07], P = 0.359) between the groups. The amounts of intraoperative fluid administered were similar between the groups (2700 [2175-3250] vs. 2900 [1950-3700] ml, median difference [95% CI] -200 [-875 to 825], P = 0.714). The secondary outcomes, including the incidence of seven major postoperative complications, duration of hospital stay, duration of intensive care unit stay, and grade of complications, were comparable between the two groups. Trends in postoperative estimated glomerular filtration rate, serum creatinine, and C-reactive protein did not differ significantly between the two groups. CONCLUSIONS: Intraoperative GDHT did not reduce the incidence of postoperative in-hospital complications during the hospital stay in patients who underwent open radical cystectomy. TRIAL REGISTRATION: This study was registered at http://www. CLINICALTRIALS: gov (Registration number: NCT03505112; date of registration: 23/04/2018).

Gender Difference in the Association of Hyperuricemia with Insulin Resistance and beta-cell Function in Nondiabetic Korean Adults: The 2019 Korea National Health and Nutrition Examination Survey.

AIMS: This study was conducted to assess the association of uric acid (UA) with the homeostasis model assessment of insulin resistance (HOMA-IR) and beta-cell function (HOMA-B) by gender in nondiabetic Korean adults. MATERIALS AND METHODS: The study was carried out using data from the 2019 Korean National Health and Nutrition Examination Survey and included nondiabetic Korean men, premenopausal women, and postmenopausal women aged 20 years or older. RESULTS: First, after adjusted for the related variables (excluding obesity), the prevalence of hyperuricemia (UA ≥ 7.0 mg/dL in men or UA ≥ 6.0 mg/dL in women) was positively associated with the quartiles of HOMA-IR and HOMA-B in men, premenopausal women, and postmenopausal women. Second, when further adjusted for obesity, hyperuricemia was positively associated with the quartiles of HOMA-IR and HOMA-B in men and postmenopausal women but not in premenopausal women. Third, after adjusted for the related variables (including obesity), UA level was positively associated with the quartiles of HOMA-IR and HOMA-B in men and postmenopausal women but not in premenopausal women. CONCLUSIONS: hyperuricemia is positively associated with insulin resistance and beta-cell function in nondiabetic Korean men and postmenopausal women but not in premenopausal women.

Relationships between common carotid artery blood flow and anesthesia, pneumoperitoneum, and head-down tilt position: a linear mixed-effect analysis.

This study investigated the effects of pneumoperitoneum and the head-down tilt position on common carotid artery (CCA) blood flow in surgical patients. METHODS: This prospective observational study included 20 patients who underwent gynecological surgery. CCA blood flow was measured using Doppler ultrasound at four-time points: awake in the supine position [T1], 3 min after anesthesia induction in the supine position [T2], 3 min after pneumoperitoneum in the supine position [T3], and 3 min after pneumoperitoneum in the head-down tilt position [T4]. Hemodynamic and respiratory parameters were also recorded at each time point. Linear mixed-effect analyses were performed to compare CCA blood flow across the time points and assess its relationship with hemodynamic parameters. RESULTS: Compared with T1, CCA blood flow decreased significantly at T2 (345.4 [288.0-392.9] vs. 293.1 [253.0-342.6], P = 0.048). CCA blood flow were also significantly lower at T3 and T4 compared with T1 (345.4 [288.0-392.9] vs. 283.6 [258.8-307.6] and 287.1 [242.1-321.4], P = 0.005 and 0.016, respectively). CCA blood flow at T3 and T4 did not significantly differ from that at T2. Changes in CCA blood flow were significantly associated with changes in cardiac index and stroke volume index (P = 0.011 and 0.024, respectively). CONCLUSION: CCA blood flow was significantly decreased by anesthesia induction. Inducing pneumoperitoneum, with or without the head-down tilt position, did not further decrease CCA blood flow if the cardiac index remained unchanged. The cardiac index and stroke volume index were significantly associated with CCA blood flow. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov (NCT04233177, January 18, 2020).

SPARC Is Highly Expressed in Young Skin and Promotes Extracellular Matrix Integrity in Fibroblasts via the TGF-ß Signaling Pathway.

The matricellular secreted protein acidic and rich in cysteine (SPARC; also known as osteonectin), is involved in the regulation of extracellular matrix (ECM) synthesis, cell-ECM interactions, and bone mineralization. We found decreased SPARC expression in aged skin. Incubating foreskin fibroblasts with recombinant human SPARC led to increased type I collagen production and decreased matrix metalloproteinase-1 (MMP-1) secretion at the protein and mRNA levels. In a three-dimensional culture of foreskin fibroblasts mimicking the dermis, SPARC significantly increased the synthesis of type I collagen and decreased its degradation. In addition, SPARC also induced receptor-regulated SMAD (R-SMAD) phosphorylation. An inhibitor of transforming growth factor-beta (TGF-ß) receptor type 1 reversed the SPARC-induced increase in type I collagen and decrease in MMP-1, and decreased SPARC-induced R-SMAD phosphorylation. Transcriptome analysis revealed that SPARC modulated expression of genes involved in ECM synthesis and regulation in fibroblasts. RT-qPCR confirmed that a subset of differentially expressed genes is induced by SPARC. These results indicated that SPARC enhanced ECM integrity by activating the TGF-ß signaling pathway in fibroblasts. We inferred that the decline in SPARC expression in aged skin contributes to process of skin aging by negatively affecting ECM integrity in fibroblasts.

Molecular Dynamics Simulation Study of the Selective Inhibition of Coagulation Factor IXa over Factor Xa.

Thromboembolic disorders, arising from abnormal coagulation, pose a significant risk to human life in the modern world. The FDA has recently approved several anticoagulant drugs targeting factor Xa (FXa) to manage these disorders. However, these drugs have potential side effects, leading to bleeding complications in patients. To mitigate these risks, coagulation factor IXa (FIXa) has emerged as a promising target due to its selective regulation of the intrinsic pathway. Due to the high structural and functional similarities of these coagulation factors and their inhibitor binding modes, designing a selective inhibitor specifically targeting FIXa remains a challenging task. The dynamic behavior of protein-ligand interactions and their impact on selectivity were analyzed using molecular dynamics simulation, considering the availability of potent and selective compounds for both coagulation factors and the co-crystal structures of protein-ligand complexes. Throughout the simulations, we examined ligand movements in the binding site, as well as the contact frequencies and interaction fingerprints, to gain insights into selectivity. Interaction fingerprint (IFP) analysis clearly highlights the crucial role of strong H-bond formation between the ligand and D189 and A190 in the S1 subsite for FIXa selectivity, consistent with our previous study. This dynamic analysis also reveals additional FIXa-specific interactions. Additionally, the absence of polar interactions contributes to the selectivity for FXa, as observed from the dynamic profile of interactions. A contact frequency analysis of the protein-ligand complexes provides further confirmation of the selectivity criteria for FIXa and FXa, as well as criteria for binding and activity. Moreover, a ligand movement analysis reveals key interaction dynamics that highlight the tighter binding of selective ligands to the proteins compared to non-selective and inactive ligands.

Time-Dependent Biosensor Fluorescence as a Measure of Bacterial Arsenic Uptake Kinetics and Its Inhibition by Dissolved Organic Matter.

Microbe-mediated transformations of arsenic (As) often require As to be taken up into cells prior to enzymatic reaction. Despite the importance of these microbial reactions for As speciation and toxicity, understanding of how As bioavailability and uptake are regulated by aspects of extracellular water chemistry, notably dissolved organic matter (DOM), remains limited. Whole-cell biosensors utilizing fluorescent proteins are increasingly used for high-throughput quantification of the bioavailable fraction of As in water. Here, we present a mathematical framework for interpreting the time series of biosensor fluorescence as a measure of As uptake kinetics, which we used to evaluate the effects of different forms of DOM on uptake of trivalent arsenite. We found that thiol-containing organic compounds significantly inhibited uptake of arsenite into cells, possibly through the formation of aqueous complexes between arsenite and thiol ligands. While there was no evidence for competitive interactions between arsenite and low-molecular-weight neutral molecules (urea, glycine, and glyceraldehyde) for uptake through the aquaglyceroporin channel GlpF, which mediates transport of arsenite across cell membranes, there was evidence that labile DOM fractions may inhibit arsenite uptake through a catabolite repression-like mechanism. The observation of significant inhibition of arsenite uptake at DOM/As ratios commonly encountered in wetland pore waters suggests that DOM may be an important control on the microbial uptake of arsenite in the environment, with aspects of DOM quality playing an important role in the extent of inhibition. IMPORTANCE The speciation and toxicity of arsenic in environments like rice paddy soils and groundwater aquifers are controlled by microbe-mediated reactions. These reactions often require As to be taken up into cells prior to enzymatic reaction, but there is limited understanding of how microbial arsenic uptake is affected by variations in water chemistry. In this study, we explored the effect of dissolved organic matter (DOM) quantity and quality on microbial As uptake, with a focus on the role of thiol functional groups that are well known to form aqueous complexes with arsenic. We developed a quantitative framework for interpreting fluorescence time series from whole-cell biosensors and used this technique to evaluate effects of DOM on the rates of microbial arsenic uptake. We show that thiol-containing compounds significantly decrease rates of As uptake into microbial cells at environmentally relevant DOM/As ratios, revealing the importance of DOM quality in regulating arsenic uptake, and subsequent biotransformation, in the environment.

Indices of ACTH-stimulated adrenal venous sampling as predictors of postsurgical outcomes in primary aldosteronism.

OBJECTIVE: This study aimed to investigate the impact of indices of adrenal venous sampling (AVS) on postsurgical outcomes in patients with primary aldosteronism (PA). DESIGN AND PATIENTS: This retrospective study determined biochemical and clinical outcomes based on ACTH-stimulated AVS parameters (lateralisation index [LI], contralateral ratio [CLR], and ipsilateral ratio [ILR]) in 251 patients with PA at 3 months after surgery. RESULTS: Modified complete biochemical success was achieved in 8 of 12 (66.7%) patients with LI = 3-4, 39 of 47 (83.0%) with LI = 4-10, and 155 of 169 (91.7%) with LI ≥ 10 (p = .004 for trend). Modified complete biochemical success was achieved in 29 of 38 (76.3%) patients with CLR ≥ 1 and ILR ≤ 2, 73 of 86 (84.9%) with CLR = 0.25-1 and ILR > 2, and 100 of 104 (96.2%) with CLR < 0.25 and ILR > 2 (p = .001 for trend). After adjusting for confounders, modified complete biochemical success was associated with an LI ≥ 10 (odds ratio [OR] = 6.32; 95% confidence interval [CI] = 1.33-29.93) using LI = 3-4 as a reference and combined CLR < 0.25 and ILR > 2 (OR = 11.49; 95% confidence interval [CI] = 2.49-53.01) using combined CLR ≥ 1 and ILR ≤ 2 as a reference. Using combined CLR ≥ 1 and ILR ≤ 2 as a reference, complete clinical success was associated with combined CLR < 0.25 and ILR > 2 (OR = 3.10; 95% CI = 1.03-9.28) and combined CLR = 0.25-1 and ILR > 2 (OR = 4.92; 95% CI = 1.64-14.76). CONCLUSION: LI ≥ 10 may be appropriate for achieving biochemical success. With ILR > 2, CLR < 0.25, and CLR < 1 may be appropriate for achieving biochemical and clinical success, respectively.

Rotation-Time Symmetry Breaking in Frustrated Chiral Nematic Driven by a Pulse-Train Waveform.

We report waveform-induced rotation-time symmetry breaking in liquid crystal director motion. Homeotropic cells filled with a negative dielectric anisotropy chiral nematic exhibit persistent and visually observable waves of director orientation with a time period of at least 30 driving field cycles. Their existence in the space of driving waveform parameters is explored. The possibility of utilizing this system, which exhibits both spatial and temporal long-range order, as a modeling tool for experimental studies on discrete time crystals is discussed.

Impact of hemodynamic instability during cytoreductive surgery on survival in high-grade serous ovarian carcinoma.

BACKGROUND: To evaluate the impact of intraoperative hypotension and hemodynamic instability on survival outcomes in patients with high-grade serous ovarian carcinoma (HGSOC). METHODS: We retrospectively identified patients with HGSOC, who underwent primary or interval debulking surgery between August 2013 and December 2019. We collected anesthesia-related variables, including the arterial blood pressure measurements (at 1-min intervals) during the surgery of patients. The cumulative duration of mean arterial blood pressure (MAP) readings under 65 mmHg and two performance measurements (median performance error [MDPE] and wobble) were calculated. We investigated associations between the factors indicating hemodynamic instability and prognosis. RESULTS: In total, 338 patients were included. Based on the cumulative duration of MAP under 65 mmHg, we divided patients into two groups: ≥30 min and <30 min. The progression-free survival (PFS) was worse in the ≥30 min group (n = 107) than the <30 min group (n = 231) (median, 18.2 vs. 23.7 months; P = 0.014). In multivariate analysis adjusting for confounders, a duration of ≥30 min of MAP under 65 mmHg was identified as an independent poor prognostic factor for PFS (adjusted HR, 1.376; 95% CI, 1.035-1.830; P = 0.028). Shorter PFS was observed in the group with a MDPE <-4.0% (adjusted HR, 1.351; 95% CI, 1.024-1.783; P = 0.033) and a wobble ≥7.5% (adjusted HR, 1.445; 95% CI, 1.100-1.899; P = 0.008). However, no differences were observed in overall survival. CONCLUSION: This study suggests that the three intraoperative variables for hemodynamic instability, cumulative duration of MAP <65 mmHg, MDPE, and wobble, might be novel prognostic biomarkers for disease recurrence in patients with HGSOC.