Context.—:Thyroid test standardization is hindered by interplatform variability, especially for immunoassays lacking metrologic traceability. Direct method-derived reference intervals (RIs) are gold standard but resource intensive. RI transference allows cost-effective multiplatform RI establishment but necessitates balanced consideration of statistical relevance, precision, and clinical feasibility. Objectives.—:To validate an RI transference framework for harmonizing RIs across platforms, using thyroid function testing as a model for assays with inconsistent reference standards. Design.—:Dual-platform framework (Roche Cobas e601 versus Beckman DxI 800) using euthyroid community midrange specimens (n = 2423) and pathology-enriched clinical leftovers (n = 300). Weighted Deming regression (constant coefficient of variation [CV]: thyroid-stimulating hormone [TSH], free thyroxine [FT4], total triiodothyronine [TT3]) and standard Deming regression (constant standard deviation: free triiodothyronine [FT3], total thyroxine [TT4]) were applied. Precision was evaluated via multiday temporal stability and concentration-dependent Monte Carlo sample size optimization. Spearman ρ, CV(b), and absolute value of bias ratio (|BR|) were benchmarked against direct RIs. Results.—:To explore multiday sampling, weighted Deming enabled accurate TSH transfer [CV(b) = 2.07%-2.89%] and acceptable precision for FT4/TT3/TT4 [CV(b) = 5.97%-10.82%]. Randomized multiday sampling reduced extreme |BR| outliers by 51% to 89%. To compare concentration-driven data sources, community-derived specimens showed superior alignment with direct RIs (FT3: |BR| = 0.581 versus 1.161 in residuals), despite weaker correlations (ρ = 0.33 versus 0.92) at n = 40. When using community-derived specimens, FT3 exhibited persistent challenges [ρ = 0.33-0.36; CV(b) = 3.07%-23.44%] attributable to methodologic heterogeneity. To determine the adaptive sample size, optimization suggested that 45 prestratified residuals with bootstrap resampling (100 × 40 pairs) improved efficiency but introduced pathologic bias (FT3 |BR| = 1.161). Conclusions：:This study established a comprehensive thyroid testing RI transference framework integrating multiday sampling, adaptive sample size, and concentration-driven data selection, identifying optimal solutions to enable cross-platform RI establishment for immunoassays. Resource-limited laboratories can further leverage multicenter direct RIs via transference to balance cost and clinical validity.

BackgroundThe regulation and secretion of hormones in the endocrine system change with aging. While these changes may influence age-related disease risks, the role of hypothalamic-pituitary-thyroid (HPT) axis sensitivity in metabolic and cardiovascular health remains unclear.MethodsThis study enrolled 13,646 participants (6,221 males, 7,425 females). Metabolic (BMI, SUA, FPG, lipoproteins) and cardiovascular (ECG, CK-MB, NT-proBNP) indices were measured. Multivariable logistic regression adjusted for age (per 10-year increment), sex, and outcome-specific confounders. Nonlinear relationships between age and TFQI were analyzed using restricted cubic splines (RCS).ResultRCS analysis revealed a significant age-dependent decline in TFQI-fT3 values, with an inflection point at 48 years (p<0.001); TFQI-fT4 showed a similar but attenuated trend. For metabolic outcomes, increased fT3 sensitivity (TFQI-fT3 Q1) was associated with lower MetS risk in older adults (>48 years) (OR 0.79, 95% CI 0.65-0.97, p=0.023), whereas no significant association was observed in younger adults (≤48 years) (all p>0.05). For cardiovascular outcomes, higher fT3 sensitivity was associated with reduced risk of abnormal ST segments in both age groups (younger: OR 0.57, 95% CI 0.32-0.97, p=0.046; older: OR 0.68, 95% CI 0.48-0.95, p=0.027). Conversely, decreased fT4 sensitivity (TFQI-fT4 Q4) specifically increased abnormal ST-segment risk in older adults (OR 1.43, 95% CI 1.04-1.96, p=0.025), with no significant effect in younger adults (OR 1.11, 95% CI 0.65-1.82, p=0.693).ConclusionEnhanced HPT axis sensitivity to fT3 increased with age (inflection point at 48 years in this study) and was associated with a lower prevalence of metabolic syndrome (in >48-year-olds) and ST-segment abnormalities (all adults).

Background The regulation and secretion of hormones in the endocrine system change with aging, including a decline in serum free triiodothyronine (fT3) and an increase in thyroid-stimulating hormone (TSH) within their reference ranges. While these changes may influence age-related disease risks, the role of hypothalamic-pituitary-thyroid (HPT) axis sensitivity in metabolic and cardiovascular health remains unclear. Methods This study enrolled 13,646 participants (6,221 males, 7,425 females). Metabolic (BMI, SUA, FPG, lipoproteins) and cardiovascular (ECG, CK-MB, NT-proBNP) indices were measured. HPT sensitivity was quantified using Thyroid Feedback Quantile-Based Index (TFQI). Multivariable logistic regression adjusted for age (per 10-year increment), sex, and outcome-specific confounders (BMI, SUA, FPG, non-HDL for ST-segment analysis). Nonlinear relationships between age and TFQI were analyzed using restricted cubic splines (RCS). Result Metabolic indicators were generally elevated in participants with decreased HPT axis sensitivity to fT3 (Q4) compared to the reference group (Q1). Restricted cubic spline analysis revealed a significant age-dependent decline in TFQI-fT3 values, with an inflection point at 48 years (p < 0.001); TFQI-fT4 showed a similar but attenuated trend. For metabolic outcomes, increased fT3 sensitivity (TFQI-fT3 Q1) was associated with lower MetS risk in older adults (> 48 years) (OR 0.79, 95% CI 0.65–0.97, p = 0.023), whereas no significant association was observed in younger adults (≤ 48 years) (all p > 0.05). For cardiovascular outcomes, higher fT3 sensitivity was significantly associated with reduced risk of abnormal ST segments in both age groups (younger: OR 0.57, 95% CI 0.32–0.97, p = 0.046; older: OR 0.68, 95% CI 0.48–0.95, p = 0.027). Conversely, decreased fT4 sensitivity (TFQI-fT4 Q4) specifically increased ST-segment risk in older adults (OR 1.43, 95% CI 1.04–1.96, p = 0.025), with no significant effect in younger adults (OR 1.11, 95% CI 0.65–1.82, p = 0.693). Conclusion Enhanced HPT axis sensitivity to fT3 increased with age (inflection at 48 years) and was associated with reduced risks of metabolic syndrome (in > 48-year-olds) and ST-segment abnormalities (all adults). These findings suggest age-specific TH regulation influences metabolic and cardiovascular health, warranting further research into underlying mechanisms.

Curcumin (Cur), a natural bioactive compound extracted from Curcuma longa, has garnered extensive interest due to its modulation of inflammation, antioxidant, and anti-tumor properties. However, its therapeutic translation remains constrained by limited systemic bioavailability. Triple-negative breast cancer (TNBC), an aggressive variant of breast malignancies, exhibits strong resistance to conventional therapies and poor prognosis. The present study was designed to clarify the mechanism through which NGR-modified nanovesicles loaded with Cur (NGR-NVs@Cur) reverse immunotherapy resistance in TNBC. Using transcriptomic and network pharmacology analysis, we identified key genes involved in TNBC development and immunotherapy resistance to determine the targets of Cur. In vitro experiments, including SA-β-gal staining, flow cytometry, and glycolysis analysis, validated that TNBC cells induce glycolysis and CD8+ T cell senescence. NGR-NVs@Cur were successfully constructed and marked by transmission electron microscopy (TEM), dynamic light scattering (DLS), pH-responsive release, and cellular uptake assays. Further cell-based studies demonstrated that NGR-NVs@Cur suppressed TNBC cell proliferation, migration, glycolysis, and reversed CD8+ T cell senescence. In vivo, both subcutaneous xenograft and adoptive T cell transfer models were developed to evaluate the therapeutic effects of NGR-NVs@Cur in combination with immune checkpoint inhibitors (ICIs, e.g., J43). The results revealed that Cur inhibited TNBC cell glycolysis and T cell senescence by activating TLR9 and suppressing the mTOR pathway, and that NGR-NVs@Cur enhanced targeted Cur delivery and effectively reversed immunotherapy resistance. This study demonstrated a novel strategy by which Cur, delivered via tumor-targeted nanovesicles, modulates glycolysis and CD8+ T cell senescence through the TLR9–mTOR axis, offering promising insights into overcoming immune resistance in TNBC.

Background: The liver function tests and noninvasive tests (NITs) play important roles in the follow-up and monitoring of fatty liver disease (FLD). Our aim is to establish annual biological variation (BV) and personalized reference intervals (prRIs) of liver function tests for the first time in order to accurately assess the status and progress of FLD. Methods: 67 fatty liver patients who participated in regular physical examination once a year for six consecutive years, were enrolled. Based on these patients, we calculated annual BV and derived parameters, including reference change value (RCV), index of individuality (II), and total variation around the true homeostatic set point (TVset) which could further be used to derive prRI. Results: We calculated the annual within-subject BV (CVI), within-person BV (CVP), RCV, II, TVset of 8 liver function tests and 3 NITs for fatty liver patients. CVI estimates of fatty liver patients for half of liver function tests were significantly lower than those of healthy people and these could lead to a lower RCV. IIs of all measurands were < 1.4 except for total bile acids (TBA). The mean of CVP is similar to the CVI; however, there is a significant heterogeneity in CVP among different subjects. Annual TVset estimates for 7 measurands were lower and prRI was also narrower in fatty liver patients than that of healthy people. Conclusion: Annual BV and their derived parameters based on fatty liver patients can provide an objective basis for the monitoring and follow-up of FLD, a global epidemic disease.

Triple-negative breast cancer (TNBC) poses as a daunting and intricate manifestation of breast cancer, highlighted by few treatment options and a poor outlook. The crucial element in fostering tumor growth and immune resistance is the polarization of tumor-associated macrophages (TAMs) into the M2 state within the tumor microenvironment (TME). To address this, we developed M2 targeting peptide-chitosan-curcumin nanoparticles (M2pep-Cs-Cur NPs), a targeted delivery system utilizing chitosan (Cs) as a carrier, curcumin (Cur) as a therapeutic agent, and targeting peptides for specificity. These NPs effectively inhibited TNBC cell proliferation ( 70

Background:Predicting endoscopic remission is crucial for optimizing clinical treatment strategies and switching biologics in Crohn's disease (CD). Mucosal healing (MH) is a key therapeutic target. This study aimed to develop a clinically applicable prediction model for early MH in CD patients receiving biological therapy. Methods:This study retrospectively analyzed 120 CD patients diagnosed between 2018 and 2023, randomly divided into a training cohort and an internal validation cohort 1. Additionally, 34 prospectively enrolled CD patients diagnosed between 2024 and 2025 formed an internal validation cohort 2. Clinical indicators and conventional imaging features were evaluated to establish a clinical model. Radiomics features were extracted from computed tomography enterography (CTE) images, with regions of interest (ROIs) manually delineated to align with ulcerated intestinal segments identified through colonoscopy. A radiomics model was constructed, and a radiomics score (Rad-score) was derived. A clinical-radiomics nomogram was then developed by integrating Rad-score with clinical risk factors. Model performance was assessed using discrimination, calibration, decision curve analysis (DCA), and clinical impact curves. Results:The clinical-radiomics nomogram demonstrated strong predictive performance, with AUC values of 0.948 (95% CI: 0.902-0.995) in the training cohort, 0.925 (95% CI: 0.805-1.0) in the internal validation cohort 1, and 0.940 (95% CI: 0.802-0.993) in the internal validation cohort 2. The nomogram outperformed standalone clinical and radiomics models, with DCA confirming its clinical utility. Conclusion:The developed nomogram effectively predicts early MH in CD patients undergoing biological therapy, providing a practical tool for clinicians to optimize treatment strategies and improve outcomes.

Background Reference intervals (RIs) play an important role in clinical decision-making. However, due to the time, labor, and financial costs involved in establishing RIs using direct means, the use of indirect methods, based on big data previously obtained from clinical laboratories, is getting increasing attention. Different indirect techniques combined with different data transformation methods and outlier removal might cause differences in the calculation of RIs. However, there are few systematic evaluations of this. Objective This study used data derived from direct methods as reference standards and evaluated the accuracy of combinations of different data transformation, outlier removal, and indirect techniques in establishing complete blood count (CBC) RIs for large-scale data. Methods The CBC data of populations aged ≥18 years undergoing physical examination from January 2010 to December 2011 were retrieved from the First Affiliated Hospital of China Medical University in northern China. After exclusion of repeated individuals, we performed parametric, nonparametric, Hoffmann, Bhattacharya, and truncation points and Kolmogorov–Smirnov distance (kosmic) indirect methods, combined with log or BoxCox transformation, and Reed–Dixon, Tukey, and iterative mean (3SD) outlier removal methods in order to derive the RIs of 8 CBC parameters and compared the results with those directly and previously established. Furthermore, bias ratios (BRs) were calculated to assess which combination of indirect technique, data transformation pattern, and outlier removal method is preferrable. Results Raw data showed that the degrees of skewness of the white blood cell (WBC) count, platelet (PLT) count, mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), and mean corpuscular volume (MCV) were much more obvious than those of other CBC parameters. After log or BoxCox transformation combined with Tukey or iterative mean (3SD) processing, the distribution types of these data were close to Gaussian distribution. Tukey-based outlier removal yielded the maximum number of outliers. The lower-limit bias of WBC (male), PLT (male), hemoglobin (HGB; male), MCH (male/female), and MCV (female) was greater than that of the corresponding upper limit for more than half of 30 indirect methods. Computational indirect choices of CBC parameters for males and females were inconsistent. The RIs of MCHC established by the direct method for females were narrow. For this, the kosmic method was markedly superior, which contrasted with the RI calculation of CBC parameters with high |BR| qualification rates for males. Among the top 10 methodologies for the WBC count, PLT count, HGB, MCV, and MCHC with a high-BR qualification rate among males, the Bhattacharya, Hoffmann, and parametric methods were superior to the other 2 indirect methods. Conclusions Compared to results derived by the direct method, outlier removal methods and indirect techniques markedly influence the final RIs, whereas data transformation has negligible effects, except for obviously skewed data. Specifically, the outlier removal efficiency of Tukey and iterative mean (3SD) methods is almost equivalent. Furthermore, the choice of indirect techniques depends more on the characteristics of the studied analyte itself. This study provides scientific evidence for clinical laboratories to use their previous data sets to establish RIs.

PURPOSE To investigate the effect of nutritional factors on bone mineral density (BMD) using quantitative computed tomography (QCT) combined with blood biochemistry in patients on maintenance hemodialysis (MHD). METHODS Sixty patients on MHD were divided into the osteopenia (n=20) or non-osteopenia (n=40) group. BMD, fat, and muscle mass were measured by QCT. The calcification of coronary artery (CCA) and hilar lymph node, CT attenuation values of the liver and spleen were also analyzed. Differences between the two groups were compared, and the risk factors of osteopenia were analyzed by logistic regression analysis. RESULTS Patients in the osteopenia group had lower albumin levels than those in the non-osteopenia group (37.84±3.00 vs 42.03±4.05 g/L, p<0.001). Logistic regression showed that patients with lower albumin levels had a higher risk of osteopenia (odds ratio: 1.462; 95% confidence interval: 1.313-1.801; p=0.003). BMD was negatively correlated with fat mass (r=-0.365, p=0.004) and positively correlated with the ratio of muscle mass to fat mass (r=0.431, p=0.001). There was no significant difference in the rate of CCA or hilar lymph nodes between the two groups. CT values of the liver and spleen were positively correlated with the duration of dialysis (r=0.55, p=0.001; r=0.42, p<0.001, respectively). CONCLUSION Low albumin levels are associated with an increased risk of osteopenia in patients on MHD. Abdominal fat is a risk factor for reduction in BMD in MHD patients, and the ratio of abdominal muscle mass to fat mass is a protective factor for BMD.

Breast microcalcifications is a characteristic feature in diagnostic imaging and a prognostic factor of breast cancer. However, the underlying mechanisms of breast microcalcifications formation are not fully understood. Previous studies have shown that upregulation of bone morphogenetic protein 2 (BMP-2) is associated with the occurrence of microcalcifications and tumor-associated macrophages (TAMs) in the tumor microenvironment can secrete BMP-2. The aim of this study is to elucidate the role of secretion of BMP-2 by TAMs in promoting microcalcifications of breast cancer through immunohistochemical staining and co-culturing of breast cancer cells with TAMs. A total of 272 patients diagnosed with primary invasive breast cancer from January 2010 to January 2012 in the First Hospital of China Medical University were included in this study. Immunohistochemical staining of CD68 (marker of entire macrophages), CD168 (marker of the M2-like macrophages) and BMP-2 were performed on 4-μm tissue microarray (TMA) sections. Following induction, THP-1 cells were differentiated to M2-like TAMs and were then co-cultured with breast cancer cells (MCF-7). Calcifications and BMP-2 expression were analyzed by Alizarin Red S staining and western blot, respectively. Immunohistochemical analysis showed that the expression of CD168 was significantly increased in tissues with microcalcifications and was correlated with the expression of BMP-2 and poor prognosis. The formation of cellular microcalcifications and BMP-2 expression were significantly increased in MCF-7 cells co-cultured with TAMs compared with MCF-7 cells alone. These findings support the hypothesis that TAMs secrete BMP-2 to induce microcalcifications in breast cancer cells and influence prognosis via multiple pathways including BMP-2 and its downstream factors.

Ovarian cancer (OV) is the most common gynaecological cancer worldwide. Immunotherapy has recently been proven to be an effective treatment strategy. The work here attempts to produce a prognostic immune-related gene pair (IRGP) signature to estimate OV patient survival. The Gene Expression Omnibus (GEO) and Cancer Genome Atlas (TCGA) databases provided the genetic expression profiles and clinical data of OV patients. Based on the InnateDB database and the least absolute shrinkage and selection operator (LASSO) regression model, we first identified a 17-IRGP signature associated with survival. The average area under the curve (AUC) values of the training, validation, and all TCGA sets were 0.869, 0.712, and 0.778, respectively. The 17-IRGP signature noticeably split patients into high- and low-risk groups with different prognostic outcomes. As suggested by a functional study, some biological pathways, including the Toll-like receptor and chemokine signalling pathways, were significantly negatively correlated with risk scores; however, pathways such as the p53 and apoptosis signalling pathways had a positive correlation. Moreover, tumour stage III, IV, grade G1/G2, and G3/G4 samples had significant differences in risk scores. In conclusion, an effective 17-IRGP signature was produced to predict prognostic outcomes in OV, providing new insights into immunological biomarkers.

OBJECTIVES:A large number of people undergo annual health checkup but accurate laboratory criterion for evaluating their health status is limited. The present study determined annual biological variation (BV) and derived parameters of common laboratory analytes in order to accurately evaluate the test results of the annual healthcare population. METHODS:A total of 43 healthy individuals who had regular healthcare once a year for six consecutive years, were enrolled using physical, electrocardiogram, ultrasonography and laboratory. The annual BV data and derived parameters, such as reference change value (RCV) and index of individuality (II) were calculated and compared with weekly data. We used annual BV and homeostatic set point to calculate personalized reference intervals (RIper) which were compared with population-based reference intervals (RIpop). RESULTS:We have established the annual within-subject BV (CVI), RCV, II, RIper of 24 commonly used clinical chemistry and hematology analytes for healthy individuals. Among the 18 comparable measurands, CVI estimates of annual data for 11 measurands were significantly higher than the weekly data. Approximately 50% measurands of II were <0.6, the utility of their RIpop were limited. The distribution range of RIper for most measurands only copied small part of RIpop with reference range index for 8 measurands <0.5. CONCLUSIONS:Compared with weekly BV, for annual healthcare individuals, annual BV and related parameters can provide more accurate evaluation of laboratory results. RIper based on long-term BV data is very valuable for "personalized" diagnosis on annual health assessments.

Neonatal hypoxic-ischemic (HI) brain injury is associated with long-term neurological disorders, and protective strategies are presently scarce. Sodium 4-phenylbutyrate (4-PBA) reportedly acts as a chemical chaperone that alleviates endoplasmic reticulum (ER) stress, which plays a critical role in neurological diseases. The present study aimed to evaluate the neuroprotective effects of 4-PBA on HI-induced neonatal brain injury in a rat model, and to characterize possible underlying mechanisms. The HI brain injury model was established by ligating the left common carotid artery in 7-day-old rats, followed by exposure to 8% oxygen for 2 h. The 4-PBA or vehicle was administered by an intracerebroventricular injection 30 min before HI. The protein expression levels of ER stress markers (GRP78, ATF6, and CHOP) were detected by western blotting at 24 h after HI insult. The activation of cAMP-response element-binding protein (CREB) was evaluated by western blotting and immunofluorescence. TUNEL and Nissl staining were performed to detect the histomorphological changes in the hippocampal neurons at 24 h and 7 days, respectively, after HI injury. From days 29 to 34 after brain HI, rats underwent Morris water maze tests to assess cognitive functioning. The results showed that pretreatment with 4-PBA decreased HI-induced excessive ER stress and neuronal injury. Moreover, CREB activation might be involved in the beneficial effects of 4-PBA on HI-induced learning and memory deficits in rats. In conclusion, the present study suggested a potential therapeutic approach of ER stress inhibition in the treatment of neonatal HI brain injury.

Background Serum total N-terminal propeptide of type I collagen (P1NP) and serum C-terminal telopeptide of type I collagen (CTX) are used as reference analytes of bone turnover in clinical application. Biological variation is important for clinical application of these biomarkers. However, the biological variation data of these biomarkers are not consistent. The present study determined biological variations of total P1NP and CTX and their confidence intervals in China using electrochemiluminescence. Methods We collected samples from 25 healthy individuals (17 women and 8 men, ranging from 22 to 49 years of age) at weekly intervals for six weeks. Samples were analysed in a single run in duplicate. Biological variations and their related parameters, such as reference change value and index of individuality (II) were calculated. The results were compared with individual studies in the EFLM database. Results Within-subject and between-subject biological variations were 8.0% and 32.5% for total P1NP and 11.4% and 38.7% for CTX, respectively. The index of individuality for total P1NP and CTX was 0.25 and 0.30, while the reference change value for P1NP values and CTX was 22.4% and 31.9%, respectively. Conclusions No difference was found in weekly biological variation of bone turnover markers between men and premenopausal women. Compared with daily and monthly variation, the present study based on weekly variation provided additional support for clinical application.

Background: When neonatal rats suffer hypoxic-ischemic brain injury (HIBI), autophagy is over-activated in the hippocampus, and inhibition of autophagy provides neuroprotection. The aim of this study was to investigate the possible roles of autophagy and Ezh2-regulated Pten/Akt/mTOR pathway in sevoflurane post-conditioning (SPC)-mediated neuroprotection against HIBI in neonatal rats. Methods: Seven-day-old Sprague-Dawley rats underwent left common artery ligation followed by 2 h hypoxia as described in the Rice-Vannucci model. The roles of autophagy and the Ezh2-regulated Pten/Akt/mTOR signaling pathway in the neuroprotection conferred by SPC were examined by left-side intracerebroventricular injection with the autophagy activator rapamycin and the Ezh2 inhibitor GSK126. Results: SPC was neuroprotective against HIBI through the inhibition of over-activated autophagy in the hippocampus as characterized by the rapamycin-induced reversal of neuronal density, neuronal morphology, cerebral morphology, and the expression of the autophagy markers, LC3B-II and Beclin1. SPC significantly increased the expression of Ezh2, H3K27me3, pAkt, and mTOR and decreased the expression of Pten induced by HI. The Ezh2 inhibitor, GSK126, significantly reversed the SPC-induced changes in expression of H3K27me3, Pten, pAkt, mTOR, LC3B-II, and Beclin1. Ezh2 inhibition also reversed SPC-mediated attenuation of neuronal loss and behavioral improvement in the Morris water maze. Conclusion: These results indicate that SPC inhibits excessive autophagy via the regulation of Pten/Akt/mTOR signaling by Ezh2 to confer neuroprotection against HIBI in neonatal rats.

Background There is no common consensus on how to define the reference population for determination of high-sensitivity cardiac troponin (hs-cTn) upper reference limit (URL). This study aimed to establish 99th percentile URLs of hs-cTnT under both 2018 AACC/IFCC criteria and improved selection criteria for further judging whether two URLs are different. Methods Applying the stratified cluster sampling protocol, this study took 1848 apparently healthy subjects in communities of Shenyang China as the screening objects. We first followed 2018 AACC/IFCC criteria using surrogate biomarker for diabetes, myocardial dysfunction, renal dysfunction, and electrocardiogram. Then, we followed improved selection criteria to exclude hypertension, overweight and obesity, and dyslipidemia by physical examination and laboratory screening. Accordingly, 99th percentile URLs of hs-cTnT were established. Results If the 2018 AACC/IFCC criteria were applied, 99th percentile URLs (90% confidence interval) of hs-cTnT male, female, and total were 19 (17-20) ng/L, 16 (15-17) ng/L, and 18 (16-19) ng/L, respectively. If added a single supplementary selection criteria, 99th percentile URLs of hs-cTnT total reduced to 16 ng/L, 17 ng/L, and 16 ng/L, respectively. If the improved selection criteria were applied, 99th percentile URLs (90% confidence interval) of hs-cTnT male, female, and total were 18 (14-24) ng/L, 13 (11-16) ng/L, and 16 (13-17) ng/L, respectively. The 99th percentile URLs of hs-cTnT male were higher than those of female in every age group. Conclusions Improved selection criteria through questionnaire survey, physical examination, and laboratory screening to further exclude hypertension, overweight and obesity, and dyslipidemia can avoid overestimation of the 99th percentile URL of hs-cTnT.

Background Reference intervals (RIs) transference can expand the applicability of established RIs. However, the study on transference methodology is insufficient, and RIs validation based on small samples cannot adequately identify transferred risk under complex situations. This study aimed to find appropriate conditions to ensure the effect of transference. Methods We established the RIs of Roche and Beckman systems for 27 analytes based on 681 healthy individuals. Roche RIs were converted into the Beckman RIs using linear regression (least squares method) which is divided into two methods - Methodref (500 test numbers with relatively narrow data range) and Methodep (80 test numbers with relatively wide data range). Taking the RIs established by Beckman results as standard, we assessed the accuracy, precision and trueness of transferred results under various conditions. Results A total of 29.6% and 48.1% of analytes were consistent between the two systems for the lower and upper reference limits, respectively. The concordance rates between transferred and measured RIs for Methodref were up to 74.1% and 92.6%, which were better than Methodep (44.4% and 59.3%). The CV of transferred reference limits decreased gradually with increasing test number under the same data range. For most analytes, excluding some electrolyte tests, we could obtain accurate results when r > 0.800 and the test number was sufficient regardless of the regression equation types. Conclusions Transferability of RIs is affected by many factors, such as correlation, test number, regression equation type, and quality requirement. To reduce the risk of transference, it is very important to select right method with reasonable conditions.

Hypoxic-ischemic brain injury (HIBI) in neonates is one of the major contributors of newborn death and cognitive impairment. Numerous animal studies have demonstrated that autophagy is substantially increased in HIBI and that sevoflurane postconditioning (SPC) can attenuate HIBI. However, if SPC-induced neuroprotection inhibits autophagy in HIBI remains unknown. To investigate if cerebral protection induced by SPC is related to decreased autophagy in the setting of HIBI. Postnatal rats at day 7 (P7) were randomly assigned to 7 different groups: Sham, HIBI, SPC–HIBI, HIBI + rapamycin, SPC–HIBI + rapamycin, HIBI + p-extracellular signal-regulated kinase (p-ERK) inhibitor, and SPC–HIBI + p-ERK inhibitor. To induce HIBI, neonatal rats underwent left common carotid artery ligation, followed by 2 h of hypoxia (8% O2). Rats in the SPC groups were treated with 1 minimum alveolar concentration ([MAC], 2.4%) SPC for 30 min after HIBI induction. Markers of autophagy and expression of ERK cascade components were measured in the rat brains after 24 h. Spatial learning and memory function were examined 29–34 days after administration of an autophagy agonist or a p-ERK inhibitor. The expression of microtubule-associated proteins 1A/1B, light chain 3B II (LC3-II) and tuberous sclerosis complex 2 (TSC2) were decreased in the SPC–HIBI group compared to the HIBI group. Expression of the p62 sequestosome 1 (P62/SQSTM1) protein, p-ERK/ERK, phospho-mammalian target of rapamycin (p-mTOR) and phospho-p70S6 were increased in SPC–HIBI group. Rats within the SPC–HIBI groups that also received the p-ERK inhibitor or autophagy inhibitor demonstrated reduced cross platform times and increased escape latency. Approximately 30 min of 2.4% SPC treatment in the P7 rat HIBI model attenuated excessive autophagy in the brain by elevating the ERK cascade. This finding provides additional insight into HIBI and identifies new targets for therapeutic approaches to treat HIBI.