Live imaging of nitric oxide release in vascular endothelial cells in response to mechanical stimuli on an organ chip

Background

Nitric oxide (NO), released from vascular endothelial cells in response to mechanical stimuli, regulates cardiac contractility and are also involved in the prevention of the development of cardiac hypertrophy.

Purpose

To establish an experimental system for live observation of NO release in response to mechanical stimuli on an organ chip.

Methods

Organ chips, which we used for the development of a heart-on-a-chip in the previous study [1], were used.

We seeded 300,000 human umbilical vein endothelial cells on a stretchable elastic membrane coated with Matrigel of a chip channel. Shear stress was applied to the cells by increasing flow rate of a peristaltic pump connected to the chip channel (Figure 1A). Pressure stimulus was applied by hydrostatic pressure. Stretch stimulus was applied by suction to the side ports of a chip using an electric syringe pump (Figure 1B). Cells were stained with 10 μM 4,5-diaminofluorescein diacetate for fluorescent live NO imaging.

Results

Monolayers of the endothelial cells formed intercellular junctions confirmed by CD31 staining (Figure 1C, yellow). Apparent permeability, which was measured by Texas red dye (MW 3000), was maintained at a low level of ∼3x10–6 cm/s until day 30, suggested the formation of robust intercellular junction.

When the endothelial cells were subjected to a pressure stimulus of 60 mmHg for 60 s, NO release was observed that lasted for >2 minutes (Figure 2A). A peak value of 1.46±1.08 (mean ± standard deviation) times the baseline was observed 271 s after the beginning of the pressure stimulus (n=251 cells). When the cells were subjected to a 1% stretch for 60 s, a peak value of 1.29±0.33 times the baseline was observed 105 s after the beginning of the stretch stimulus (Figure 2B). A shear stress of 0.01 dyn/cm2 hardly increased NO release (1.20±0.27 times the baseline, Figure 2C).

Conclusion

The system for live NO imaging in vascular endothelial cells in response to mechanical stimuli was established using organ-on-a-chip. The heart-on-a-chip with endothelial cells will be useful in elucidating the effects of mechanical stimulus such as hypertension on the contractile function and the remodeling of the heart.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Japan Society for the Promotion of Science

Impact of metabolic syndrome and its components on clinical severity and long-term prognosis in patients with premature myocardial infarction

Background

Metabolic syndrome (MetS) is involved in the occurrence, development and prognosis of cardiovascular diseases, especially acute myocardial infarction (AMI). In recent years, the trend of AMI at a younger age has gradually attracted people's attention. Relevant studies have confirmed that MetS affects the prognosis of people aged ≥45 with AMI. However, there is still a lack of research on MetS in people with premature myocardial infarction (PMI).

Purpose

To explore the impact of MetS and its components on clinical severity and long-term prognosis in PMI patients.

Methods

772 Patients with AMI who aged ≤45 years old from 2015 to 2020 in a hospital were enrolled. The patients were divided into MetS group (n=417) and non-MetS group (n=355) according to the criteria proposed by NCEP ATP III in 2005 (Any 3 of the following 5): 1) Hypertension: BP ≥130/85 mmHg or consistent hypertensive patients undergoing treatment; 2) Hypertriglyceridemia: fasting plasma triglyceride ≥1.7 mmol/L; 3) Fasting HDL-C <1.0 mmol/L in men and <1.3 mmol/L in women. 4) Hyperglycemia: fasting blood glucose level ≥6.1 mmol/L or known diabetic patients undergoing treatment; 5) Central obesity: BMI ≥28.0 kg/m2. Patients were followed for median of 42 months for major adverse cardiovascular events (MACE). The parameters of clinical severity were compared using logistic regression analysis. Cox regression were used to analyze the relationship between MetS and its components and prognosis.

Results

A total of 772 patients were included in the analysis. Hyperglycemia was associated with multi-vessel disease (OR=1.700, 95% CI 1.172–2.464, P=0.005) and Syntax score ≥33 (OR=2.736, 95% CI 1.241–6.032, P=0.013).Increased MACE were observed in the MetS group (17.9% vs 10.3%, P=0.004) after 42 months follow-up. The Kaplan-Meier curve also showed significant differences (P<0.001). MetS was an independent risk factor for MACE (HR=2.181, 95% CI 1.392–3.418, P=0.001). Of each component of the definition, BMI ≥28.0 kg/m2 (HR=2.047, 95% CI 1.229–3.410, P=0.006) and hyperglycemia (HR=2.911, 95% CI 1.850–4.580, P<0.001) were independent risk factors for MACE.

Conclusions

In patients with PMI, (1) hyperglycemia usually indicates more severe lesions; (2) MetS as a whole was an independent risk factor for MACE; (3) Of each component of the MetS, BMI ≥28.0 kg/m2 and hyperglycemia were associated with MACE.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): This research was supported by the Key Project of Scientific and Technological Support Plan of Tianjin in 2020

[Transcriptomic analysis of tuberculosis peptide-based vaccine MP3RT in humanized mice]

Objective: To identify the differentially expressed genes (DEGs) induced by tuberculosis peptide-based vaccine MP3RT in a humanized mouse model using transcriptomics technology. Methods: This study was conducted from August 2019 to February 2022. We used edgeR software to screen DEGs with a fold change greater than or equal to 1.5 and a P value less than 0.05 as screening conditions. Gene ontology (GO), Kyoto encyclopedia of genes and genomes (KEGG), and protein interaction network analyses were performed on the screened DEGs. Then, these DEGs were verified by RT-qPCR and statistically analyzed by GraphPad Prism 8 software. Results: A total of 367 DEGs (214 up-regulated and 153 down-regulated) were identified by transcriptomics. Bioinformatics analysis showed that the GO enrichment of the DEGs mentioned above significantly focused on cell metabolism, growth, apoptosis, inflammation, and other terms. In contrast, the KEGG enrichment significantly focused on inflammatory pathways such as the MAPK signaling pathway. Protein interaction network analysis showed that protein Abl1 had the highest aggregation, the highest aggregation coefficient, and the best connectivity. RT-qPCR results showed that gene expressions of cpne4 (t=2.48, P=0.048 0), h2-q10 (t=2.95, P=0.025 6), mef2c (t=2.87, P=0.028 4), cr2 (t=3.23, P=0.178), ablim1 (t=2.91, P=0.033 5), dll1 (t=2.70, P=0.027 3) and ms4a2 (t=3.03, P=0.019 2) genes in the MP3RT group were significantly up-regulated than those in the PBS group, while gene expressions of cd163l1 (t=2.56, P=0.043 0), il1r1 (t=2.91, P=0.022 7) and cd34 (t=2.42, P=0.046 2) genes in the MP3RT group were significantly down-regulated than those in the PBS group. Conclusions: The MP3RT vaccine induced 367 DEGs in humanized mice, which were associated with metabolic and immune responses. Furthermore, we found that p38 MAPK and JNK/MAPK signaling pathways played an important role in the molecular mechanism of the MP3RT vaccine.

[Nutrition management of patients with acute exacerbation of chronic obstructive pulmonary disease hospitalized in Respiratory Intensive Care Unit]

Acute exacerbation of chronic obstructive pulmonary disease (COPD) is an important part of the course of COPD. Patients with life-threatening acute exacerbation need to be admitted to the respiratory intensive care unit (RICU) for treatment in time. Malnutrition is common in COPD patients, and nutritional risk also has a high prevalence in patients with COPD exacerbation, which is closely associated with the clinical outcome and mortality of these patients. Identifying patients with high nutritional risk and providing appropriate nutritional treatment will help to improve survival rate, shorten length of hospital stay and reduce complications. This review describes the potential mechanisms of malnutrition in patients with COPD, the nutritional risk assessment of patients with COPD exacerbation hospitalized in RICU, the selection of nutritional treatment methods and formulas, and the relevant problems of nutritional management of patients required noninvasive ventilation, hoping to provide information for the optimization of nutritional treatment strategy for acute exacerbation of COPD and the exploration of clinical research in the future.

Evidence for Nonlinear Gluon Effects in QCD and Their Mass Number Dependence at STAR

The STAR Collaboration reports measurements of back-to-back azimuthal correlations of di-π^{0}s produced at forward pseudorapidities (2.6<η<4.0) in p+p, p+Al, and p+Au collisions at a center-of-mass energy of 200 GeV. We observe a clear suppression of the correlated yields of back-to-back π^{0} pairs in p+Al and p+Au collisions compared to the p+p data. The observed suppression of back-to-back pairs as a function of transverse momentum suggests nonlinear gluon dynamics arising at high parton densities. The larger suppression found in p+Au relative to p+Al collisions exhibits a dependence of the saturation scale Q_{s}^{2} on the mass number A. A linear scaling of the suppression with A^{1/3} is observed with a slope of -0.09±0.01.

Residual feed intake in peripartal dairy cows is associated with differences in milk fat yield, ruminal bacteria, biopolymer hydrolyzing enzymes, and circulating biomarkers of immunometabolism

Residual feed intake (RFI) measures feed efficiency independent of milk production level, and is typically calculated using data past peak lactation. In the current study, we retrospectively classified multiparous Holstein cows (n = 320) from 5 of our published studies into most feed-efficient (M-eff) or least feed-efficient (L-eff) groups using performance data collected during the peripartal period. Objectives were to assess differences in profiles of plasma biomarkers of immunometabolism, relative abundance of key ruminal bacteria, and activities of digestive enzymes in ruminal digesta between M-eff and L-eff cows. Individual data from cows with ad libitum access to a total mixed ration from d -28 to d +28 relative to calving were used. A linear regression model including dry matter intake (DMI), energy-corrected milk (ECM), changes in body weight (BW), and metabolic BW was used to classify cows based on RFI divergence into L-eff (n = 158) and M-eff (n = 162). Plasma collected from the coccygeal vessel at various times around parturition (L-eff = 60 cows; M-eff = 47 cows) was used for analyses of 30 biomarkers of immunometabolism. Ruminal digesta collected via esophageal tube (L-eff = 19 cows; M-eff = 29 cows) was used for DNA extraction and assessment of relative abundance (%) of 17 major bacteria using real-time PCR, as well as activity of cellulase, amylase, xylanase, and protease. The UNIVARIATE procedure of SAS 9.4 (SAS Institute Inc.) was used for analyses of RFI coefficients. The MIXED procedure of SAS was used for repeated measures analysis of performance, milk yield and composition, plasma immunometabolic biomarkers, ruminal bacteria, and enzyme activities. The M-eff cows consumed less DMI during the peripartal period compared with L-eff cows. In the larger cohort of cows, despite greater overall BW for M-eff cows especially in the prepartum (788 vs. 764 kg), no difference in body condition score was detected due to RFI or the interaction of RFI × time. Milk fat content (4.14 vs. 3.75 ± 0.06%) and milk fat yield (1.75 vs. 1.62 ± 0.04 kg) were greater in M-eff cows. Although cumulative ECM yield did not differ due to RFI (1,138 vs. 1,091 ± 21 kg), an RFI × time interaction due to greater ECM yield was found in M-eff cows. Among plasma biomarkers studied, concentrations of nonesterified fatty acids, β-hydroxybutyrate, bilirubin, ceruloplasmin, haptoglobin, myeloperoxidase, and reactive oxygen metabolites were overall greater, and glucose, paraoxonase, and IL-6 were lower in M-eff compared with L-eff cows. Among bacteria studied, abundance of Ruminobacter amylophilus and Prevotella ruminicola were more than 2-fold greater in M-eff cows. Despite lower ruminal activity of amylase in M-eff cows in the prepartum, regardless of RFI, we observed a marked linear increase after calving in amylase, cellulase, and xylanase activities. Protease activity did not differ due to RFI, time, or RFI × time. Despite greater concentrations of biomarkers reflective of negative energy balance and inflammation, higher feed efficiency measured as RFI in peripartal dairy cows might be associated with shifts in ruminal bacteria and amylase enzyme activity. Further studies could help address such factors, including the roles of the liver and the mammary gland.

Fn1 Regulates the Third Pharyngeal Pouch Patterning and Morphogenesis

The parathyroid and thymus are derived from the common primordia, the third pharyngeal pouch. During their development, endodermal cells actively interact with surrounding mesenchymal cells, mainly derived from neural crest cells (NCCs). However, the mechanism by which NCCs regulate the development of the third pharyngeal pouch remains largely unknown. In this study, we showed that fibronectin 1 (Fn1), which is synthesized by NCCs, modulates the functions of NCCs in the third pharyngeal pouch patterning and in the morphogenesis of the thymus/parathyroid. Loss of Fn1 in NCCs leads to decreased Foxn1 expression in the presumptive thymus domain at E11.5. In the mutant, we detected upregulation of the Hedgehog signaling activity in the presumptive parathyroid domain and downregulation of Bmp4 in the presumptive thymus domain. Tbx1, a Hedgehog signaling target gene in endoderm development, was ectopically expanded to the presumptive mutant thymus domain at E11.5. Fgf10, an important gene regulating the proliferation of endoderm development, was downregulated in the mutant NCCs. At later organogenesis stages, derivatives of the third pharyngeal pouch endoderm of mutant embryos were abnormal, showing conditions such as hypoparathyroidism, hypoplastic thymus, and ectopic thymus and parathyroid. These data support that Fn1 plays an important role in NCCs by regulating the patterning of the third pharyngeal pouch and morphogenesis of the thymus/parathyroid.

[Clinical characteristics and whole exome sequencing results of patients with Möbius syndrome]

Objective: To analyze the clinical characteristics of patients with Möbius syndrome (MBS) and to explore likely pathogenic genes. Methods: Cross-sectional study. The study enrolled 18 sporadic MBS patients who visited the Eye Center of Beijing Tongren Hospital Affiliated to Capital Medical University from July 2018 to December 2021. All patients completed the general information questionnaire and underwent detailed ophthalmic examinations and general physical examinations. Seventeen patients received MRI examination of cranial nerves and the orbit. The peripheral venous blood of all patients and their nuclear family members was collected, the genomic DNA was extracted, and the pathogenic gene variations that may lead to MBS were identified by whole exome sequencing and bioinformatics analysis. Results: Among the 18 patients, there were 8 males and 10 females, and the age was (4.5±4.0) years (range, 8 months to 17 years). All patients showed congenital, bilateral or unilateral abduction deficit and facial weakness, which met the minimum diagnostic criteria of MBS. Among them, bilateral abduction deficit (16/18) and bilateral facial weakness (15/18) were more common. Nine patients were orthotopic in primary position, eight presented with esotropia, and one showed hypotropia. All patients had ametropia, of which 4 patients were diagnosed as amblyopia. Fifteen patients were also accompanied by other multiple congenital malformations, mainly characterized by abnormal development of glossopharynx (14/18) and limbs (5/18), and 7 patients were also accompanied by motor retardation. In addition, 9 patients had intrauterine exposure to adverse factors. Among the 17 patients who underwent MRI, 15 patients had bilateral hypoplasia of the abducens nerve, two had unilateral hypoplasia of the abducens nerve, 14 showed bilateral hypoplasia of the facial nerve, and three showed hypoplasia of the left facial nerve. Besides, some patients were also accompanied by hypoplasia of other cranial nerves, mainly the glossopharyngeal nerve and the hypoglossal nerve. No definite pathogenic variations were found by whole exome sequencing and bioinformatics analysis. Conclusions: The main clinical features of MBS were congenital abduction deficit and facial weakness, with complicated manifestations and variable severity. MRI showed absence or thinning of the abducens nerve and the facial nerve. The results of MRI can be used as a supplement to the diagnostic criteria of MBS. The mutation detection rate of MBS was low, and half of patients had exposure to adverse factors during pregnancy, suggesting that there was a multifactorial pathogenic mechanism in MBS.

Susceptibility-weighted imaging cannot distinguish radionecrosis from recurrence in brain metastases after radiotherapy: a comparison with high-grade gliomas

AIM

To explore the efficiency of susceptibility-weighted imaging (SWI) in the differential diagnosis of recurrence from radionecrosis in brain metastases (BM) and in high-grade gliomas (HGG).

MATERIALS AND METHODS

From September 2016 to November 2018, 56 patients with BM and 42 patients with HGG were included in this retrospective study. BM and HGG were assigned to the recurrence and radionecrosis groups according to their histopathology or follow-up results. The proportion of dark signal intensity (proDSI), which was defined as the area of dark signal on SWI or the enhancing area on contrast-enhanced T1-weighted imaging (T1WI), was calculated for each patient. Analysis of variance (ANOVA) with Tukey's honestly significant difference test was used for the repeat multiple comparisons. Receiver operating characteristic curve analysis was performed to validate the diagnostic performance.

RESULTS

For HGG, the proDSI in the recurrence group was significantly lower than that in the radionecrosis group (0.13 ± 0.05 versus 0.43 ± 0.11, p<0.001); however, for BM, no statistical difference was found between groups (0.49 ± 0.09 versus 0.46 ± 0.08, p=0.26). proDSI had the best diagnostic performance (AUC = 0.87, 95% CI: 0.76-0.98; sensitivity = 0.87; specificity = 0.88) for HGG, when a cut-off value of 0.21 was selected.

CONCLUSIONS

Semi-quantitative analysis using SWI is feasible for the differential diagnosis between recurrence and radionecrosis in HGG, but is not feasible in BM. Semi-quantitative assessment based on SWI should interpreted with caution in BM after radiotherapy in clinical practice.

Measurements of Proton High-Order Cumulants in sqrt[s_{NN}]=3 GeV Au+Au Collisions and Implications for the QCD Critical Point

We report cumulants of the proton multiplicity distribution from dedicated fixed-target Au+Au collisions at sqrt[s_{NN}]=3.0  GeV, measured by the STAR experiment in the kinematic acceptance of rapidity (y) and transverse momentum (p_{T}) within -0.5<y<0 and 0.4<p_{T}<2.0  GeV/c. In the most central 0%-5% collisions, a proton cumulant ratio is measured to be C_{4}/C_{2}=-0.85±0.09 (stat)±0.82 (syst), which is 2σ below the Poisson baseline with respect to both the statistical and systematic uncertainties. The hadronic transport UrQMD model reproduces our C_{4}/C_{2} in the measured acceptance. Compared to higher energy results and the transport model calculations, the suppression in C_{4}/C_{2} is consistent with fluctuations driven by baryon number conservation and indicates an energy regime dominated by hadronic interactions. These data imply that the QCD critical region, if created in heavy-ion collisions, could only exist at energies higher than 3 GeV.

Measurements of _{Λ}^{3}H and _{Λ}^{4}H Lifetimes and Yields in Au+Au Collisions in the High Baryon Density Region

We report precision measurements of hypernuclei _{Λ}^{3}H and _{Λ}^{4}H lifetimes obtained from Au+Au collisions at sqrt[s_{NN}]=3.0  GeV and 7.2 GeV collected by the STAR experiment at the Relativistic Heavy Ion Collider, and the first measurement of _{Λ}^{3}H and _{Λ}^{4}H midrapidity yields in Au+Au collisions at sqrt[s_{NN}]=3.0  GeV. _{Λ}^{3}H and _{Λ}^{4}H, being the two simplest bound states composed of hyperons and nucleons, are cornerstones in the field of hypernuclear physics. Their lifetimes are measured to be 221±15(stat)±19(syst)  ps for _{Λ}^{3}H and 218±6(stat)±13(syst)  ps for _{Λ}^{4}H. The p_{T}-integrated yields of _{Λ}^{3}H and _{Λ}^{4}H are presented in different centrality and rapidity intervals. It is observed that the shape of the rapidity distribution of _{Λ}^{4}H is different for 0%-10% and 10%-50% centrality collisions. Thermal model calculations, using the canonical ensemble for strangeness, describes the _{Λ}^{3}H yield well, while underestimating the _{Λ}^{4}H yield. Transport models, combining baryonic mean-field and coalescence (jam) or utilizing dynamical cluster formation via baryonic interactions (phqmd) for light nuclei and hypernuclei production, approximately describe the measured _{Λ}^{3}H and _{Λ}^{4}H yields. Our measurements provide means to precisely assess our understanding of the fundamental baryonic interactions with strange quarks, which can impact our understanding of more complicated systems involving hyperons, such as the interior of neutron stars or exotic hypernuclei.

A food-grade vector for Streptococcus thermophilus based on the α-complementation of β-galactosidase

Streptococcus thermophilus is a common yogurt starter that consumes lactose as its primary carbon source. The enzyme β-galactosidase is essential for the lactose metabolism and the growth of this species. Streptococcus thermophilus appears to be a promising cell factory. Food-grade vectors have advantages in heterologous protein expression. This study aimed to determine whether the β-galactosidase of S. thermophilus has the α-complementary characteristic and to develop a novel food-grade vector based on this phenomenon. The N-terminal 7 to 36 AA residues of the β-galactosidase in S. thermophilus were deleted. The obtained mutant S. thermophilus Δα lost β-galactosidase activity and growth ability in the lactose medium. Subsequently, plasmids expressing α-fragments with different lengths of 1 to 36 (Sα1), 1 to 53 (Sα2), and 1 to 88 (Sα3) AA were constructed and transformed into S. thermophilus Δα. Recombinant S. thermophilus Δα expressing Sα2 or Sα3 recovered the ability to grow in the lactose medium, and their β-galactosidase activity accounted for 24.5% or 11.5% of the wild strain, respectively. These results indicated that the α-complementation system of β-galactosidase existed in S. thermophilus. Based on the characteristic, a food-grade vector pSEα was constructed. Except for Sα2, vector pSEα expressed the α-donor derived from E. coli β-galactosidase. This facilitated the construction of recombinant plasmids in E. coli DH5α and thus improved the transformation efficiency of S. thermophilus. Green fluorescent protein as a reporter protein could be highly expressed in S. thermophilus using this vector. As a result, pSEα is an efficient and safe vector for S. thermophilus with potential food applications.

[Construction of a nomogram model for predicting 2-year survival rate of small cell lung cancer based on more comprehensive variables]

Objective: To construct a novel prognostic nomogram model based on more comprehensive variables for patients with small-cell lung cancer (SCLC). Methods: The data of 722 patients with SCLC confirmed by pathology in Affiliated Cancer Hospital of Shanxi Medical University from January 2015 to December 2018 were retrospectively analyzed [including 592 males and 130 females, aged from 23 to 82(61±9) years]. A random seed count of 133 was used to divide those patients into training set (n=422) and validation set (n=300). Kaplan-Meier was used for survival curves analysis and univariate Log-rank test was used for evaluating the influence of clinical variables on the prognosis of sclc, variables with P<0.05 in univariate analysis were included in a multivariate Cox regression model. The nomogram was constructed based on the variables which P<0.05 in multivariate analysis. Receiver operating characteristic (ROC) curve, calibration by Integrated Brier score (IBS) and clinical net benefit by decision curve analysis (DCA) were used to evaluate model discriminative power, prediction error value, and clinical net benefit, and compared with the American Joint Committee on Cancer 8th TNM. Results: Male, abnormal monocyte (MON) counts, abnormal neuron specific enolase (NSE), abnormal cytokeratin 19 fragment (Cyfra211), M1a stage, M1b stage, M1c stage, radiotherapy (RT), chemotherapy ≥4 cycles and prophylactic cranial irradiation (PCI) were prognostic factors for SCLC[HR(95%CI)=1.39(1.00-1.92), 1.29(1.02-1.63), 1.41(1.11-1.80), 2.02(1.48-2.76), 1.09(0.77-1.55), 1.44(0.94-2.22), 2.01(1.49-2.71), 0.75(0.57-0.98), 0.40(0.31-0.51)and 0.42(0.26-0.68), respectively, all P<0.05]. The area under ROC curve (AUC) of the nomogram in training set and validation set were 0.814(95%CI: 0.765-0.862)and 0.787 (95%CI: 0.725-0.849), which were higher than TNM [0.616(95%CI: 0.558-0.674) and 0.648(95%CI: 0.581-0.715)].The calibration curve showed a good correlation between the nomogram prediction and actual observation for the 2-year overall survival (OS). IBS indicted a lower prediction error rate (training set: 0.132 vs 0.169; validation set: 0.138 vs 0.169). DCA showed a wider threshold range than TNM (training set: 0.01-0.96 vs 0.01-0.85, validation set: 0.01-0.94 vs 0.01-0.86) and a greater improvement of the clinical net benefit (in training set the nomogram had a greater clinical benefit than TNM in the range of 0.19-0.96, and remained in validation set in the range of 0.19-0.94). Conclusion: The established nomogram model for predicting 2-year OS in patients with SCLC based on 8 variables, including gender, MON, NSE, Cyfra211, M stage, RT, CT cycles and PCI can be used for an more accurately prognosis prediction and reference for therapeutic regimen selection.

[The diagnosis and treatment of G3 neuroendocrine tumors according to the new NCCN guideline]

Gastrointestinal pancreas (GEP) is the most common site of neuroendocrine neoplasms (NENs). In 2019, the World Health Organization (WHO) classification for GEP NET was updated to include a new category of well-differentiated high-grade (Ki 67>20%) GEP-NET G3, distinct from high-grade poorly differentiated neuroendocrine carcinoma (NEC). As a new category, NET G3 are considered a molecularly, radiologically, and prognostically distinct entity compared to NEC and NET G1/G2. The management of NET G3 remains a challenge awaiting future trials taking into consideration the unique characteristics of this new category. The latest NCCN clinical guidelines of neuroendocrine and adrenal tumors firstly gave the recommendation of diagnosis and treatment of G3 NET separately from NEC and G1/G2 NET. Hereon,we aim to summarize the management of G3 NET in combination with the new NCCN guidelines and the current evidences.

[The function of auditory cortex in the elderly using functional near-infrared spectroscopy technology]

Objective: Functional near-infrared spectroscopy (fNIRS) was used to study the effect of aging on the neuroimaging characteristics of cerebral cortex in the process of speech perception. Method: Thirty-four adults with normal hearing were recruited from March 2021 to June 2021, including 17 in the young group, with 6 males, 11 females, age (32.1±5.0) years, age range 20-39 years. and 17 in the elderly group, with 6 males, 11 females, age (63.2±2.8) years, age range 60-70 years. The test material was the sentence table of the Mandarin Hearing Test in Noise (MHINT). The task state block experiment design was adopted, and the temporal lobe, Broca's area, Wernicke's area, motor cortex were used as regions of interest. Objective brain imaging technology (fNIRS) combined with subjective psychophysical testing method was used to analyze the activation area and degree of cerebral cortex related to auditory speech perception in the elderly and young people under different listening conditions (quiet, signal-to-noise ratio of 10 dB, 5 dB, 0 dB, -5 dB). SPSS 23 software was used for statistical analysis. Result: The activation area and degree of activation in the elderly group were lower than those in the young group under each task condition; The number of activation channels in the young group were significantly more than those in the old group, and the number of activation channels in the left hemisphere were more than those in the right hemisphere, but there was no difference in the number of activation channels. There were more channels affected by age in the left hemisphere than in the right hemisphere. The activation degree of the young group when the signal-to-noise ratio was 0 dB was significantly higher than that of other signal-to-noise ratio conditions (P<0.05), but there was no significant difference in the old group under the five conditions (P>0.05). The speech recognition score of the young group was higher than that of the old group under all conditions. When the quiet and signal-to-noise ratio was 10 dB, the correct score of the two groups was equal or close to 100%. With the gradual decrease of signal-to-noise ratio, there was a significant difference between the two groups when the signal-to-noise ratio was 5 dB. The speech recognition accuracy of the young group decreased significantly when the signal-to-noise ratio was 0 dB, while that of the old group decreased significantly when the signal-to-noise ratio was 5 dB. Conclusions: With the increase of age, the speech perception in noisy environment and the activity of cerebral cortex gradually deteriorate, and the speech dominance hemisphere (left hemisphere) will be significantly affected by aging. The overall activation area and activation degree of the elderly under different speech tasks are lower than those of the young.

[Relationship between body mass index and sexual development in Chinese children]

Objective: To investigate the relationship between body mass index (BMI) and sexual development in Chinese children. Methods: A nationwide multicenter and population-based large cross-sectional study was conducted in 13 provinces, autonomous regions and municipalities of China from January 2017 to December 2018. Data on sex, age, height, weight were collected, BMI was calculated and sexual characteristics were analyzed. The subjects were divided into four groups based on age, including ages 3-<6 years, 6-<10 years, 10-<15 years and 15-<18 years. Multiple Logistic regression models were used for evaluating the associations of BMI with sexual development in children. Dichotomous Logistic regression was used to compare the differences in the distribution of early and non-early puberty among normal weight, overweight and obese groups. Curves were drawn to analyze the relationship between the percentage of early puberty and BMI distribution in girls and boys at different Tanner stages. Results: A total of 208 179 healthy children (96 471 girls and 111 708 boys) were enrolled in this study. The OR values of B2, B3 and B4+ in overweight girls were 1.72 (95%CI: 1.56-1.89), 3.19 (95%CI: 2.86-3.57), 7.14 (95%CI: 6.33-8.05) and in obese girls were 2.05 (95%CI: 1.88-2.24), 4.98 (95%CI: 4.49-5.53), 11.21 (95%CI: 9.98-12.59), respectively; while the OR values of G2, G3, G4+ in overweight boys were 1.27 (95%CI: 1.17-1.38), 1.52 (95%CI: 1.36-1.70), 1.88 (95%CI: 1.66-2.14) and in obese boys were 1.27 (95%CI: 1.17-1.37), 1.59 (95%CI: 1.43-1.78), and 1.93 (95%CI: 1.70-2.18) (compared with normal weight Tanner 1 group,all P<0.01). Analysis in different age groups found that OR values of obese girls at B2 stage and boys at G2 stage were 2.02 (95%CI: 1.06-3.86) and 2.32 (95%CI:1.05-5.12) in preschool children aged 3-<6 years, respectively (both P<0.05). And in the age group of 6-10 years, overweight girls had a 5.45-fold risk and obese girls had a 12.54-fold risk of B3 stage compared to girls with normal BMI. Compared with normal weight children, the risk of early puberty was 2.67 times higher in overweight girls, 3.63 times higher in obese girls, and 1.22 times higher in overweight boys, 1.35 times higher in obese boys (all P<0.01). Among the children at each Tanner stages, the percentage of early puberty increased with the increase of BMI, from 5.7% (80/1 397), 16.1% (48/299), 13.8% (27/195) to 25.7% (198/769), 65.1% (209/321), 65.4% (157/240) in girls aged 8-<9, 10-<11 and 11-<12 years, and 6.6% (34/513), 18.7% (51/273), 21.6% (57/264) to 13.3% (96/722), 46.4% (140/302), 47.5% (105/221) in boys aged 9-<10, 12-<13 and 13-<14 years, respectively. Conclusions: BMI is positively correlated with sexual development in both Chinese boys and girls, and the correlation is stronger in girls. Obesity is a risk factor for precocious puberty in preschool children aged 3-<6 years, and 6-<10 years of age is a high risk period for early development in obese girls.

Short-term outcomes of intracorporeal and extracorporeal anastomosis in robotic right colectomy: a systematic review and meta-analysis

Ileocolic anastomosis is performed via extracorporeal or intracorporeal techniques in robotic right hemicolectomy. The aim of this meta-analysis was to compare the short-term outcomes of intracorporeal anastomosis (IA) and extracorporeal anastomosis (EA) for robotic right colectomy. The EMBASE, PubMed, and Cochrane Library databases were searched systematically (from inception until March 1, 2020) for randomized and non-randomized control trials reporting the short-term outcomes of IA and EA for robotic right colectomy. Five observational cohort studies involving 585 participants were included in our meta-analysis. Compared to the EA group, the IA group showed significantly longer operation time [weighted mean difference (WMD): 28.88, 95% confidence interval (CI) 13.88-43.89, p = 0.0002], lower rate of anastomotic leak (odds ratio: 0.26, 95% CI 0.08-0.85, p = 0.03), and shorter time to first flatus (WMD: - 0.57, 95% CI - 0.95 to 0.19, p = 0.003). However, pooled results revealed no difference in blood loss, complications, wound infection, incisional hernia, length of incision, and hospital stay between the IA and EA groups (p < 0.05). This meta-analysis indicated that IA was superior to EA in terms of anastomotic leak and time to first flatus, but inferior in terms of operation time. Large-scale, multicenter, randomized studies are needed to confirm our findings.

Probing the Gluonic Structure of the Deuteron with J/ψ Photoproduction in d+Au Ultraperipheral Collisions

Understanding gluon density distributions and how they are modified in nuclei are among the most important goals in nuclear physics. In recent years, diffractive vector meson production measured in ultraperipheral collisions (UPCs) at heavy-ion colliders has provided a new tool for probing the gluon density. In this Letter, we report the first measurement of J/ψ photoproduction off the deuteron in UPCs at the center-of-mass energy sqrt[s_{NN}]=200  GeV in d+Au collisions. The differential cross section as a function of momentum transfer -t is measured. In addition, data with a neutron tagged in the deuteron-going zero-degree calorimeter is investigated for the first time, which is found to be consistent with the expectation of incoherent diffractive scattering at low momentum transfer. Theoretical predictions based on the color glass condensate saturation model and the leading twist approximation nuclear shadowing model are compared with the data quantitatively. A better agreement with the saturation model has been observed. With the current measurement, the results are found to be directly sensitive to the gluon density distribution of the deuteron and the deuteron breakup process, which provides insights into the nuclear gluonic structure.

Search for the Chiral Magnetic Effect via Charge-Dependent Azimuthal Correlations Relative to Spectator and Participant Planes in Au+Au Collisions at sqrt[s_{NN}]=200 GeV

The chiral magnetic effect (CME) refers to charge separation along a strong magnetic field due to imbalanced chirality of quarks in local parity and charge-parity violating domains in quantum chromodynamics. The experimental measurement of the charge separation is made difficult by the presence of a major background from elliptic azimuthal anisotropy. This background and the CME signal have different sensitivities to the spectator and participant planes, and could thus be determined by measurements with respect to these planes. We report such measurements in Au+Au collisions at a nucleon-nucleon center-of-mass energy of 200 GeV at the Relativistic Heavy-Ion Collider. It is found that the charge separation, with the flow background removed, is consistent with zero in peripheral (large impact parameter) collisions. Some indication of finite CME signals is seen in midcentral (intermediate impact parameter) collisions. Significant residual background effects may, however, still be present.

Interaction of biofilm and efflux pump in clinical isolates of carbapenem resistant P. aeruginosa

OBJECTIVE

Carbapenem-resistant P. aeruginosa (CRPA) is particularly worrisome because of its resistance against multiple antimicrobial agents which reduces treatment options. The efflux pump decreases antibiotic abundance, and biofilm impairs the penetration of antibiotics. The aim of the present study was to evaluate the role and relationship of efflux pump and biofilm formation in CRPA isolates obtained from different clinical samples.

PATIENTS AND METHODS

A total of 110 different clinical samples were collected from three tertiary medical hospitals. The samples were subjected to isolation and identification by standard operating procedures. Species level were identified using Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry system. Antibiotic susceptibility testing was done by broth microdilution method. Crystal violet (CV) staining for observing the biofilm forming ability and amplification of efflux pump mexA gene were also performed on clinical CRPA isolates. Three efflux pump MexAB-OprM regulatory genes were analyzed using sequencing methods. The expression of mexA gene both in biofilm and planktonic bacteria was observed by Quantitative real-time PCR (qRT-PCR).

RESULTS

The results showed that 110 samples were CRPA and among them 83 (75.5%) were MDR isolates. The CV staining showed 105 (95.5%) isolates as biofilm producers while 78 (74.3%) MDR isolates showed biofilm formation. mexA hyperexpression was detected in 27 (24.5%) CRPA isolates while 26 (96.3%) in biofilm forming isolates and 96.3% (26/27) in MDR P. aeruginosa. Multiple mutations in nalC, nalD, and mexR genes were detected. The distinct difference confirmed that the expression of mexA gene in P. aeruginosa biofilm producer was significantly higher than that of planktonic bacteria in vitro, and the efflux pump inhibitor PAβN significantly inhibited biofilms in CRPA isolated from clinical samples.

CONCLUSIONS

The biofilm and efflux pumps might be two intertwined processes involved in CRPA isolates. Their synergistic effect magnified the drug resistance characteristics of P. aeruginosa.

Complete Genomic Data of Pantoea ananatis Strain TZ39 Associated with New Bacterial Blight of Rice in China

Pantoea ananatis is a phytopathogen infecting many economically important crops, including rice worldwide. Here, we report the complete genome of P. ananatis strain TZ39 identified as causative agent of a new bacterial blight of rice that emerged in China in 2020. The assembled genome consists of one circular chromosome of 4,483,976 bp and two plasmids of 135,135 and 276,579 bp. This complete genome of the first Chinese pathogenic P. ananatis strain will provide new insights into the traits of pathogenicity on genomic level from China and worldwide.

Preoperative MRI of breast squamous cell carcinoma: diagnostic value of distinguishing between two subtypes

AIM

To retrospectively analyse the clinical and MRI data of primary squamous cell carcinoma (SCC), particularly pure squamous cell carcinoma (PSCC) and mixed squamous cell carcinoma (MSCC).

MATERIALS AND METHODS

The MRI data and clinicopathological characteristics of 20 patients with histopathologically confirmed SCC of the breast, including eight PSCC patients and 12 MSCC patients, from multiple centres between January 2013 and December 2020 were analysed retrospectively.

RESULTS

Nine of 12 patients in the MSCC group showed hyperintensity on T1-weighted imaging (WI), while this feature was not observed in the PSCC group (p=0.001). Most of the PSCC group showed rim enhancement, whereas most of the MSCC group showed heterogeneous enhancement (p=0.007). In addition, there was no significant difference in the thickness of the rim enhancement and the percentage of necrotic components in the tumours between the two types of SCCs of the breast (p=0.545 and p=0.662, respectively). Four patients (4/12) in the MSCC group had sentinel lymph node metastasis, while only one patient (1/8) in the PSCC group showed lymph node metastasis (p=0.603). Metastatic disease occurred in 25% of patients with PSCC and in approximately 41.7% of patients with MSCC.

CONCLUSION

The signal on T1WI and internal enhancement characteristics were the key features for differentiating PSCC and MSCC. Therefore, MRI phenotypes may provide additional information for the pathological classification of breast SCC.

Measurement of the Sixth-Order Cumulant of Net-Proton Multiplicity Distributions in Au+Au Collisions at sqrt[s_{NN}]=27, 54.4, and 200 GeV at RHIC

According to first-principle lattice QCD calculations, the transition from quark-gluon plasma to hadronic matter is a smooth crossover in the region μ_{B}≤T_{c}. In this range the ratio, C_{6}/C_{2}, of net-baryon distributions are predicted to be negative. In this Letter, we report the first measurement of the midrapidity net-proton C_{6}/C_{2} from 27, 54.4, and 200 GeV Au+Au collisions at the Relativistic Heavy Ion Collider (RHIC). The dependence on collision centrality and kinematic acceptance in (p_{T}, y) are analyzed. While for 27 and 54.4 GeV collisions the C_{6}/C_{2} values are close to zero within uncertainties, it is observed that for 200 GeV collisions, the C_{6}/C_{2} ratio becomes progressively negative from peripheral to central collisions. Transport model calculations without critical dynamics predict mostly positive values except for the most central collisions within uncertainties. These observations seem to favor a smooth crossover in the high-energy nuclear collisions at top RHIC energy.

[Prognostic evaluation value of (18)F-FDG PET-CT in Hodgkin's lymphoma after treatment]

Objective: To investigate the prognostic value of (18)F-fluorodeoxygen-D-glucose-positron emission tomography /computerized tomography ((18)F-FDG-PET-CT) in Hodgkin's lymphoma (HL) at the end of first-line treatment (PET-end), by comparing the ratio of maximum standardized uptake value (SUV(max)) of lesion and liver SUV (rLL), SUV(max) reduction between baseline PET (PET-0) and PET-end (ΔSUV(max)), and Deauville 5-point scale (5-PS). Methods: Patients with HL newly treated in our hospital from August 2006 to December 2015 were retrospectively analyzed. All the patients enrolled in the study underwent post-treatment FDG PET-CT. The rLL and ΔSUV(max) were calculated, and all the cases were scored using Deauville 5-PS. The receiver operating characteristic (ROC) approach was applied to identify the optimal cut-point value, and survival curves according to different PET-CT assessment methods were estimated using the Kaplan-Meier analysis. The prognostic efficacy of different PET-CT assessment methods was compared, and DeLong test was used to verify it. Kaplan-Meier method and multivariate analysis using the Cox proportional hazards model were performed to analyze the potential independent risk factors. Results: There were 5 patients progressed within a 3-year follow-up. In the three PET-CT assessment methods, the predictive value of rLL and Deauville 5-PS were significant effective. ROC analysis for rLL as a progression predictor showed an optimal cut-point of 1.29. Deauville 5-PS=4 and rLL=1.29 showed the best prognostic accuracy. The sensitivity of rLL and Deauville 5-PS were both 80.0%, and the specificity of each was 98.0% and 93.7%, respectively. The positive predictive value (PPV) and negative predictive value (NPV) of rLL were 66.7% and 98.7%, while the PPV and NPV of 5-PS were 44.4% and 98.7%. The 3-years progression-free survival (PFS) rates of rLL≥1.29 group and rLL<1.29 group were 33.3% and 98.7%, with significant difference (P<0.001). The 3-years PFS rates of post-treatment Deauville 5-PS<4 group and Deauville 5-PS≥4 group were 98.7% and 55.6%, with significant difference (P<0.001). The prognostic evaluation efficacy of rLL was positively correlated with that of Deauville 5-PS (r=0.75, P<0.05). Area under curves (AUC) of rLL and Deauville 5-PS were 0.93 (95%CI: 0.825-1.000) and 0.91 (95%CI: 0.757-1.000), respectively. DeLong test showed the significant difference between the two methods (P<0.05). The univariate analysis results showed that clinical baseline stage, post-treatment rLL and Deauville 5-PS were associated with the prognoses of HL patients (P<0.05). The multivariate analysis results showed that post-treatment rLL and Deauville 5-PS were independent prognostic factors of HL (P<0.05). Conclusions: The rLL and Deauville 5-PS are potential prognostic factors for HL response assessment. The new semi-quantitative method rLL has methodological advantages over visual analysis, and it is a good supplement for Deauville 5-PS. rLL can improve prognostic evaluation accuracy of PET-CT and is useful to early identify patients with HL at a high risk of relapsing after first-line treatment.

Diversity and functions of microbes in surface sediments under heavy metal pollution of western Chaohu Lake

Heavy metal pollution is a global concern. Targeting at the surface sediments in western Chaohu Lake and using metagenome sequencing, we probed into the mechanism of how microbes adapted to heavy metal-polluted sediments under natural conditions. It was found the heavy metal pollution intensity of the three typical sampling places ranked as estuary of Nanfeihe River (NFH) > Zhongmiao Town (HZ) > Hongshizui (HSZ). Totally 129 phyla, 2631 genera and 12 989 species were detected in the sediment samples, and HSZ, HZ and NFH had 35, 51 and 67 exclusive genera, respectively. The bacterial biomass and virus quantity from NFH accounted for 22·84 and 70·69% of total quantities, respectively, and the microbial community compositions in NFH were also different from those in HSZ and HZ. Metagenomics sequencing and functional gene annotation showed NFH contained many functional genes related to nucleic acid transport and metabolism, ribosome structures and biological origin, replication recombining and repair and inorganic ion transport and metabolism. Kyoto Encyclopedia of Genes and Genomes analysis suggested the sediments from NFH were rich in enzymes correlated with heavy metal transport and reduction. Our findings offer some scientific basis for Chaohu Lake control and microbe resource utilization.

The potential mechanism of PPP2R3A in myocardial cells and its interacting proteins

OBJECTIVE

PPP2R3A plays a key role in the cardiac pathological and physiological processes, yet little is known about how the protein involved in normal myocardium formation and the protein-protein interaction pathways involved. To address this issue, we investigated the role of PPP2R3A in cardiac myocytes and identify PPP2R3A specific protein interaction partners to accelerate the developmental process of the mechanistic studies.

MATERIALS AND METHODS

PPP2R3A-silenced primary myocardial cell of neonatal rats and H9c2 cells were established by infecting shRNA lentiviral particles. RT-PCR and Western blot were used to determine the expression of PPP2R3A and silencing efficiency. The cell viability was analyzed by CCK-8 kit, then the cell cycles and apoptosis assays were detected by flow cytometry. Novel protein-protein interactions of PPP2R3A were detected by Yeast Two-Hybrid assays using a high-quality human primary cardiomyocyte cDNA library.

RESULTS

PPP2R3A-silencing rat primary cardiomyocytes and H9c2 cells were established successfully, and the expression of PPP2R3A was downregulated significantly as confirmed by RT-PCR and Western blot. PPP2R3A silencing can inhibit the myocardial cell proliferation, arrest the cell cycle in the S phase and promote the cardiomyocytes apoptosis. 19 potential candidates like COL1A2, GIPC1and BCL6 specifically interact with PPP2R3A, and COL1A2 was the highest screening frequency, covering 12.5% of the 24 clones. These partners are highly enriched in signaling pathways associated with a variety of cellular processes.

CONCLUSIONS

A series of studies have discovered that PPP2R3A was closely associated with heart failure and arrhythmia. Our data further confirmed PPP2R3A plays an important role in the cardiomyocytes and PPP2R3A in the regulation of cardiac events via its interaction partners. Therefore, it is a potential therapeutic target for the disease.

Speciation and Potential Ecological Risk of Heavy Metals in Soils from Overlapped Areas of Farmland and Coal Resources in Northern Xuzhou, China

Contamination caused by heavy metals (HMs) in soil of overlapped area of farmland and coal resources (OAFCR) has impact on crops. The concentrations and speciation of As, Cd, Cr, Cu, Pb and Zn were investigated in topsoil of an OAFCR in Xuzhou, China. The results showed that mean concentrations of all six metals were higher than the background values of Xuzhou city and Cd was moderate accumulated with the maximum I_geo equalled to 2.13. Cd showed moderate contamination level (IP_i = 1.75) and potential ecological risk (Er = 44.06). Most of the total Cr, Cu, Ni, Pb, and Zn were presented in the residual forms (above 60%), and the percentages of reducible, oxidisable and residual forms of Pb were 23%, 21% and 43% respectively. Pb and Cd reflected a moderate degree of potential ecological risk and a considerable migration risk and ecotoxicity.

Stoichioproteomics study of differentially expressed proteins and pathways in head and neck cancer

Hypoxia is a prominent feature of head and neck cancer. However, the oxygen element characteristics of proteins and how they adapt to hypoxia microenvironments of head and neck cancer are still unknown. Human genome sequences and proteins expressed data of head and neck cancer were retrieved from pathology atlas of Human Protein Atlas project. Then compared the oxygen and carbon element contents between proteomes of head and neck cancer and normal oral mucosa-squamous epithelial cells, genome locations, pathways, and functional dissection associated with head and neck cancer were also studied. A total of 902 differentially expressed proteins were observed where the average oxygen content is higher than that of the lowly expressed proteins in head and neck cancer proteins. Further, the average oxygen content of the up regulated proteins was 2.54% higher than other. None of their coding genes were distributed on the Y chromosome. The up regulated proteins were enriched in endocytosis, apoptosis and regulation of actin cytoskeleton. The increased oxygen contents of the highly expressed and the up regulated proteins might be caused by frequent activity of cytoskeleton and adapted to the rapid growth and fast division of the head and neck cancer cells. The oxygen usage bias and key proteins may help us to understand the mechanisms behind head and neck cancer in targeted therapy, which lays a foundation for the application of stoichioproteomics in targeted therapy and provides promise for potential treatments for head and neck cancer.

Development of a human heart-on-a-chip model using induced pluripotent stem cells, fibroblasts and endothelial cells

Background

The use of animal models in cardiovascular research is associated with two serious, intrinsic problems: inaccuracy in the extrapolation of data obtained from animals such as rodents due to different cardiac physiology and animal ethics.

Purpose

To develop an artificial human heart model for cardiovascular research using organ-on-a-chip technology and human cells

Methods

Organ chips made of silicone (polydimethylsiloxane) that have two microfluidic channels, a top channel and a bottom channel, separated by a 50-μm thick membrane with 7-μm pores hexagonally packed at 40-μm intervals (Figure 1), were used in this study.

We seeded 10,000 human umbilical vein endothelial cells on the membrane surface in the bottom channel to mimic the vasculature. Next, we seeded a mixture of 100,000 human-induced pluripotent stem cells (hiPSCs) and 50,000 human gingival fibroblasts on the membrane surface in the top channel (Figure 1). Human gingival fibroblasts facilitate cardiac differentiation of hiPSCs [1]. We performed the cardiac differentiation of hiPSCs using a previously described protocol [1]. Culture medium was perfused at a constant rate of 60 μl/h to maintain the culture.

Results

We observed spontaneous contraction of hiPSC-derived cardiomyocytes 20–26 days after the start of the differentiation protocol. Simultaneously, we conducted live intracellular calcium imaging using a fluorogenic calcium-sensitive dye, Cal-520 AM (5 μM in the culture medium). hiPSC-derived cardiomyocytes exhibited a periodic, coordinated pattern of calcium influx synchronised with their contraction under fluorescence microscopy (Figure 2A). Moreover, we found that the β-adrenergic agonist noradrenaline elevated the heart rate of hiPSC-derived cardiomyocytes on the organ chips in a dose-dependent manner (Figures 2A, B).

After observing the contraction and intracellular calcium influx of hiPSC-derived cardiomyocytes, we performed immunocytochemistry. Confocal microscopy indicated that the fluorescent signal obtained from anti-cardiac troponin T antibody staining in the top channel exhibited a typical striated pattern with 1.56±0.12-μm interval that reflected sarcomere structure (Figure 2C, yellow). Moreover, the fluorescent signal obtained from anti-CD31 antibody staining in the bottom channel exhibited a typical pattern at the boundary between cells, which is expected at the cell–cell junction of endothelial cells.

Conclusion

We developed a human heart-on-a-chip model that was confirmed by the functional response to noradrenaline and the histological evidence of sarcomere structure and vasculature, with a capability of live imaging. We expect that this model would be useful for examining the physiological function and for the pharmacological analysis of not only the normal heart but also the heart that reflects specific patient's pathophysiology using patient-derived hiPSCs.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Japan Society for the Promotion of Science Figure 1Figure 2

5-hydroxymethylcytosine profiles in circulating cell-free DNA as candidate diagnostic and predictive biomarkers for coronary artery disease

Background

DNA 5-hydroxymethylcytosine (5hmC) modification is an epigenetic marker involved in a range of biological processes. However, little information is available about its role in coronary artery disease (CAD), particularly in the acute phase of acute coronary syndrome (ACS).

Aims

To investigate whether 5hmC modification correlates with the pathogenesis and progression of CAD and whether 5hmC in cfDNA can be used as biomarkers.

Methods

We utilized 5hmC-Seal to generate genome-wide 5hmC profiles in plasma cell-free DNA (cfDNA) of normal coronary artery (NCA, n=200) controls and CAD patients, including stable coronary artery disease (sCAD, n=200) patients and ACS patients (n=371). To investigate the correlation between 5hmC modifications and CAD subtypes, we separated samples into training and validation cohorts and developed a 5hmC-based logistic regression model from the training cohort to predict the progression of CAD in the validation cohort.

Results

We detected a significant difference of 5hmC enrichment in gene bodies from CAD patients compared with NCA individuals. Particularly, our results showed that patients of CAD subgroups can be well separated from NCA individuals by 5hmC markers. The prediction performance of the model established by differentially regulated 5hmC modified genes achieved an AUC of 0.81 (sCAD vs. NCA) and 0.74 (ACS vs. NCA) in validation cohorts.

Conclusions

Our results demonstrated that patients of CAD subtypes and NCA individuals had distinct differences in 5hmC enrichment. 5hmC markers derived from plasma cfDNA may potentially serve as a clinical-applicable, minimally invasive, and liquid biopsy-based approach to diagnose CAD, particularly used to predict the occurrence of fetal ACS.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): Chinese Academy of Medical Science (CAMS) Innovation Fund for Medical Sciences Figure 1Figure 2

Methionine supplementation during a hydrogen peroxide challenge alters components of insulin signaling and antioxidant proteins in subcutaneous adipose explants from dairy cows

Enhanced postruminal supply of methionine (Met) during the peripartal period alters protein abundance of insulin, AA, and antioxidant signaling pathways in subcutaneous adipose tissue (SAT). Whether SAT is directly responsive to supply of Met and can induce molecular alterations is unknown. Our objective was to examine whether enhanced Met supply during an oxidative stress challenge in vitro alters insulin, AA, inflammation, and antioxidant signaling-related protein networks. Four late-lactation Holstein cows (average 27.0 kg of milk per day) were used for SAT collection. Tissue was incubated in duplicate for 4 h in a humidified incubator with 5% CO₂ at 37°C according to the following experimental design: control medium with an "ideal" profile of essential AA (CTR; Lys:Met 2.9:1), CTR plus 100 μM H₂O₂ (HP), or CTR with greater Met supply plus 100 μM H₂O₂ (HPMET; Lys:Met 2.5:1). Molecular targets associated with insulin signaling, lipolysis, antioxidant nuclear factor, erythroid 2 like 2 (NFE2L2), inflammation, and AA metabolism were determined through reverse-transcription quantitative PCR and western blotting. Data were analyzed using the MIXED procedure of SAS 9.4 (SAS Institute Inc.). Among proteins associated with insulin signaling, compared with CTR, HP led to lower abundance of phosphorylated AKT serine/threonine kinase (p-AKT) and solute carrier family 2 member 4 (SLC2A4; insulin-induced glucose transporter). Although incubation with HPMET restored abundance of SLC2A4 to levels in the CTR and upregulated abundance of fatty acid synthase (FASN) and phosphorylated 5'-prime-AMP-activated protein kinase (p-AMPK), it did not alter p-AKT, which remained similar to HP. Among proteins associated with AA signaling, compared with CTR, challenge with HP led to lower abundance of phosphorylated mechanistic target of rapamycin (p-MTOR), and HPMET did not restore abundance to CTR levels. Among inflammation-related targets studied, incubation with HPMET led to greater protein abundance of nuclear factor kappa B subunit p65 (NFKB-RELA). The response in NFKB observed with HPMET was associated with a marked upregulation of the antioxidant transcription regulator NFE2L2 and the antioxidant enzyme glutathione peroxidase 1 (GPX1). No effects of treatment were detected for mRNA abundance of proinflammatory cytokines or antioxidant enzymes, underscoring the importance of post-transcriptional regulation. Overall, data indicated that short-term challenge with H₂O₂ was particularly effective in reducing insulin and AA signaling. Although a greater supply of Met had little effect on those pathways, it seemed to restore the protein abundance of the insulin-induced glucose transporter. Overall, the concomitant upregulation of key inflammation and antioxidant signaling proteins when a greater level of Met was supplemented to oxidant-challenged SAT highlighted the potential role of this AA in regulating the inflammatory response and oxidant status. Further studies should be conducted to assess the role of postruminal supply of Met and other AA in the regulation of immune, antioxidant, and metabolic systems in peripartal cow adipose tissue.