Single-cell RNA sequencing reveals the altered innate immunity in immune checkpoint inhibitor-related myocarditis

Myocarditis has emerged as a rare but lethal immune checkpoint inhibitor (ICI)-associated toxicity. However, the exact mechanism and the specific therapeutic targets remain underexplored. In this study, we aim to characterise the transcriptomic profiles based on single-cell RNA sequencing from ICI-related myocarditis. Peripheral blood mononuclear cell (PBMC) samples were collected from four groups for single-cell RNA sequencing: (1) patients with newly diagnosed lung squamous cell carcinoma before treatment (Control Group); (2) patients with lung squamous cell carcinoma with PD-1 inhibitor therapy who did not develop myocarditis (PD-1 Group); (3) patients during fulminant ICI-related myocarditis onset (Myocarditis Group); and (4) Patients with fulminant ICI-related myocarditis during disease remission (Recovery Group). Subcluster determination, functional analysis, single-cell trajectory and cell-cell interaction analysis were performed after scRNA-seq. Bulk-RNA sequencing was performed for further validation. Our results revealed the diversity of cellular populations in ICI-related myocarditis, marked by their distinct transcriptional profiles and biological functions. Monocytes, NKs as well as B cells contribute to the regulation of innate immunity and inflammation in ICI-related myocarditis. With integrated analysis of scRNA-seq and bulk sequencing, we identified S100A protein family as a potential serum marker for ICI-related myocarditis. Our study has created a cell atlas of PBMC during ICI-related myocarditis, which would shed light on the pathophysiological mechanism and potential therapeutic targets of ICI-related myocarditis in continuous exploration.

Statins aggravate insulin resistance through reduced blood glucagon-like peptide-1 levels in a microbiota-dependent manner

Statins are currently the most common cholesterol-lowering drug, but the underlying mechanism of statin-induced hyperglycemia is unclear. To investigate whether the gut microbiome and its metabolites contribute to statin-associated glucose intolerance, we recruited 30 patients with atorvastatin and 10 controls, followed up for 16 weeks, and found a decreased abundance of the genus Clostridium in feces and altered serum and fecal bile acid profiles among patients with atorvastatin therapy. Animal experiments validated that statin could induce glucose intolerance, and transplantation of Clostridium sp. and supplementation of ursodeoxycholic acid (UDCA) could ameliorate statin-induced glucose intolerance. Furthermore, oral UDCA administration in humans alleviated the glucose intolerance without impairing the lipid-lowering effect. Our study demonstrated that the statin-induced hyperglycemic effect was attributed to the Clostridium sp.-bile acids axis and provided important insights into adjuvant therapy of UDCA to lower the adverse risk of statin therapy.

Predictive value of serum TBA for 2-year MACEs in ACS patients undergoing PCI: a prospective cohort study

Bile acids play important roles in lipid metabolism and glucose homeostasis. Limited research exist on the association between serum total bile acid (TBA) levels and major adverse cardiovascular events (MACEs) in patients with acute coronary syndrome (ACS), particularly those with comorbid type 2 diabetes mellitus (T2DM). This study was conducted to examine the relationship between baseline serum TBA level and T2DM status in patients with ACS after percutaneous coronary intervention (PCI) and to identify the predictive value of TBA levels for a 2-year risk of MACEs. 425 ACS patients underwent PCI were recruited and divided into three groups based on baseline serum TBA concentration. An analysis of the association between the T2DM status and baseline serum TBA levels was conducted using univariate linear regression and multivariate linear regression. The predictive relevance of serum TBA levels was evaluated using the receiver operating characteristic (ROC) curve and Cox regression. Kaplan-Meier curves were employed to analyze the differences among groups in predicting MACEs over a 2-year follow-up period. Baseline serum TBA levels were higher in ACS patients who were diagnosed with T2DM (the median 3.6 µmol/L) than those without T2DM (the median 3.0 µmol/L). T2DM status in ACS patients was positively correlated with baseline serum TBA concentrations (β: 1.7, 95% confidence interval [CI] 0.3-3.0), particularly in the male (β: 2.0, 95% CI 0.3-3.6) and 50-69-year-old (β: 2.5, 95% CI 0.6-4.4) populations. The areas under the ROC curve of baseline serum TBA levels predicted MACEs in ACS and ACS-T2DM patients following PCI were 0.649 (95% CI 0.595-0.703) and 0.783 (95% CI 0.685-0.881), respectively. Furthermore, Cox regression analysis showed that baseline serum TBA level was associated with the occurrence of MACEs in patients with ACS after PCI over a 2-year follow-up period, especially in those diagnosed with T2DM, whose baseline TBA concentration was lower than 10.0 µmol/L. ACS Patients with T2DM had higher serum TBA levels. TBA level at baseline was an independent predictor of MACEs in ACS patients who underwent PCI, especially with comorbid T2DM.

The Predictive Values of White Blood Cell Indices (Lymphocyte and Eosinophilic Granulocyte) for Heart Failure in Acute Coronary Syndrome Patients Following Percutaneous Coronary Intervention: A Prospective Cohort Study

Background

White blood cell (WBC) indices are strongly associated with cardiovascular disease, but data on the prognostic values of these parameters in patients with acute coronary syndrome (ACS) following percutaneous coronary intervention (PCI) are sparse. The current study aimed to investigate the relationship between baseline WBC indices levels and the incidence of heart failure (HF) in ACS patients after PCI and explore the predictive values over a 2-year follow-up period.

Methods

A total of 416 consecutive ACS patients treated with PCI were enrolled and received a median of 27.7 months follow-up. Univariate and multivariate Cox regression analyses and the receiver operating characteristic (ROC) curves were performed.

Results

Baseline lymphocyte (LYMPH) count, eosinophil (EO) count and eosinophil percentage (EO %) were higher in patients who experienced HF over a 2-year follow-up. In multivariate Cox proportional hazards analysis, LYMPH count, EO count and EO % were independently associated with the occurrence of HF (hazard ratio [HR] = 12.876, P = 0.025; HR = 16.625, P = 0.004; HR = 1.196, P = 0.031, respectively). The area under the ROC curve of baseline EO count predicting the occurrence of HF in ACS patients following PCI was 0.625 (P = 0.037). For patients aged 60 years and above, who had PCI or history of coronary artery bypass grafting, the higher EO count, the higher the risk of HF.

Conclusion

Elevated baseline LYMPH count, EO count and EO % were independently associated with the incidence of HF in ACS patients following PCI, suggesting that WBC indices might be available, simple, and cost-efficient biomarkers with predictive value, especially for patients aged more than 60 years.

Higher serum triglyceride can predict recurrent coronary revascularization events in patients undergoing percutaneous coronary intervention with baseline LDL-C <55 mg/dL

Patients with low baseline low-density lipoprotein cholesterol (LDL-C) but experiencing recurrent coronary revascularization events have been rarely investigated. In this retrospective cohort study, we enrolled patients undergoing percutaneous coronary intervention (PCI) with baseline LDL-C <55 mg/dL at the First Affiliated Hospital of Xi'an Jiaotong University between January and December 2017. Subsequent ischemia-driven coronary revascularization events and all-cause death were documented during a 4-year follow-up. Cox analysis was used to evaluate the association between baseline clinical characteristics and long-term events. As a result, among 388 patients (mean age 63 years; 79.1% male) enrolled, 32 patients underwent recurrent revascularization events, and 38 patients occurred all-cause death. After adjustment for age, diabetes mellitus, multi-vessel disease, and lipoprotein(a), multivariate Cox analysis showed that baseline serum triglyceride (TG) (HR 1.691, 95% CI 1.178 to 2.428, p=0.004) was an independent predictor of recurrent coronary revascularization events. Kaplan-Meier analysis revealed that a higher TG level (≥1.17 mmol/L, determined by receiver operating characteristic curve) was associated with increased risk of recurrent revascularization events than lower TG level (<1.17 mmol/L) (p=0.021). Female (HR 2.647, 95% CI 1.350 to 5.190, p=0.005) and previous atrial fibrillation (HR 3.163, 95% CI 1.403 to 7.132, p=0.006) were associated with increased risk of all-cause death. In conclusion, for patients undergoing PCI with baseline LDL-C <55 mg/dL, higher baseline TG can predict recurrent coronary revascularization events.

MED1 Regulates BMP/TGF-β in Endothelium: Implication for Pulmonary Hypertension

BACKGROUND

Dysregulated BMP (bone morphogenetic protein) or TGF-β (transforming growth factor beta) signaling pathways are imperative in idiopathic and familial pulmonary arterial hypertension (PAH) as well as experimental pulmonary hypertension (PH) in rodent models. MED1 (mediator complex subunit 1) is a key transcriptional co-activator and KLF4 (Krüppel-like factor 4) is a master transcription factor in endothelium. However, MED1 and KLF4 epigenetic and transcriptional regulations of the BMP/TGF-β axes in pulmonary endothelium and their dysregulations leading to PAH remain elusive. We investigate the MED1/KLF4 co-regulation of the BMP/TGF-β axes in endothelium by studying the epigenetic regulation of BMPR2 (BMP receptor type II), ETS-related gene (ERG), and TGFBR2 (TGF-β receptor 2) and their involvement in the PH.

METHODS

High-throughput screening involving data from RNA-seq, MED1 ChIP-seq, H3K27ac ChIP-seq, ATAC-seq, and high-throughput chromosome conformation capture together with in silico computations were used to explore the epigenetic and transcriptional regulation of BMPR2, ERG, and TGFBR2 by MED1 and KLF4. In vitro experiments with cultured pulmonary arterial endothelial cells (ECs) and bulk assays were used to validate results from these in silico analyses. Lung tissue from patients with idiopathic PAH, animals with experimental PH, and mice with endothelial ablation of MED1 (EC-MED1^-/-) were used to study the PH-protective effect of MED1.

RESULTS

Levels of MED1 were decreased in lung tissue or pulmonary arterial endothelial cells from idiopathic PAH patients and rodent PH models. Mechanistically, MED1 acted synergistically with KLF4 to transactivate BMPR2, ERG, and TGFBR2 via chromatin remodeling and enhancer-promoter interactions. EC-MED1^-/- mice showed PH susceptibility. In contrast, MED1 overexpression mitigated the PH phenotype in rodents.

CONCLUSIONS

A homeostatic regulation of BMPR2, ERG, and TGFBR2 in ECs by MED1 synergistic with KLF4 is essential for the normal function of the pulmonary endothelium. Dysregulation of MED1 and the resulting impairment of the BMP/TGF-β signaling is implicated in the disease progression of PAH in humans and PH in rodent models.

In-hospital initiation of PCSK9 inhibitor and short-term lipid control in patients with acute myocardial infarction

Background

Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors have been shown to improve cardiovascular outcomes when added to conventional statin therapy. This study aims to investigate the efficacy and safety of in-hospital initiation of PCSK9 inhibitors among patients with acute myocardial infarction (AMI) based on real-world experience.

Methods and results

Data were collected from the Biobank of the First Affiliated Hospital of Xi’an Jiaotong University between January 2016 and December 2020. A total of 7556 AMI patients were screened for eligibility. Propensity Score Match (PSM) was employed, and covariates were age, sex, admission blood pressure and lipid profiles.

Eligible participants were (1) propensity-matched 1:2:2 of statin plus evolocumab (dual therapy) vs. statin vs. statin plus ezetimibe. Ninety-five statin plus evolocumab users achieved significantly decreased low density lipoprotein (LDL) levels (0.92 ± 0.62 mmol/L in the 1st month and 1.17 ± 0.73 in the 3rd month) and a promising attainment rate of LDL (79.5% in the 1st month and 80.0% in the 3rd month) compared to the other two groups. (2) Propensity-matched 1:2:2 of statin plus ezetimibe evolocumab (triple therapy) vs. statin vs. statin plus ezetimibe. Similarly, 75 triple medication users achieved significantly decreased LDL levels and a promising attainment rate of LDL compared to the other two groups. In-hospital mortality and readmission rates within 3 months were then analyzed, and a decreased readmission rate was observed with PCSK9i therapy.

Conclusions

Based on the present single-center real-world PSM-adjusted study, PCSK9i has been effective in short-term lipid control among AMI patients. The long-term effectiveness for reducing major cardiovascular events among AMI patients based on real-world experience remains to be explored.

Trial registration

The study was registered at ClinicalTrials.gov, ClinicalTrials.gov ID: NCT05184530

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12944-022-01724-9.

Case Report: Acute Myocarditis Due to PD-L1 Inhibitor Durvalumab Monotherapy in a Patient With Lung Squamous Cell Carcinoma

Background

Durvalumab, as a PD-L1 inhibitor, is commonly used for the treatment of various cancers. Adverse events associated with the therapy include hepatitis, nephritis, dermatitis, and myocarditis. Especially, myocarditis as an adverse event after PD-L1 inhibitor therapy is characterized for its low incidence and high mortality.

Case Summary

Here we present a rare case of a 67-year-old male with lung squamous cell carcinoma complicated with empyema who experienced myocarditis after only PD-L1 inhibitor durvalumab monotherapy. He presented with markedly decrease left ventricular ejection fraction, elevated Natriuretic peptide BNP, Troponin T, Troponin I, ESR, CRP and interleukin-6. The electrocardiogram showed sinus tachycardia, low voltage of limb leads, T wave inversion in anterior waves and V1-V3 QS type. Myocardial injury occurred in a short period and quickly returned to normal after glucocorticoids therapy.

Conclusion

This case report is of clinical value for the treatment of PD-L1 related myocarditis.

Cardiotoxicity Related to Immune Checkpoint Inhibitors: A Real-World Retrospective Analysis

Background

Cardiotoxicity related to immune checkpoint inhibitors (ICIs) is a rare but potentially lethal. In ICI-associated adverse events, evidence of cardiotoxicity and clinical predictive factors related to ICI is lacking. Here, we aim to assess the incidence and predictive factors of cardiotoxicity related to ICIs in real-world practice.

Objective

We retrospectively analyzed consecutive patients who received PD-1 or PD-L1 at the First Affiliated Hospital of Xi'an Jiaotong University. Clinical characteristics and cardiac lesion markers were collected both at baseline and during longitudinal follow-up from the Biobank database. Follow-up CKMB and NT-proBNP levels and ratios were then evaluated.

Results

A total of 2,304 patients with either PD-1 or PDL-1 utilization between August 2018 and April 2021 were collected. The average age was 59.44 ± 11.45 among PD-1 inhibitor utilizer and 58.97 ± 12.16 among PDL-1 inhibitor utilizer. The baseline creatine kinase isoenzyme MB (CKMB) levels were 17 ± 19 U/L in PD-1 inhibitor users and 17 ± 23 U/L in PDL-1 inhibitor users. Majority of patients were male, with advanced stage cancer, and received ICIs as second-line therapy. The longitudinal change of cardiac enzymes and NT-pro BNP were collected. Cardiac lesion as defined by three times increase of CKMB happens in only minority of patients receiving ICIs therapy. It is also identified that increased CKMB happened in PD-1 inhibitor groups, but not PDL-1 inhibitor groups.

Conclusion

We evaluated the profile of cardiotoxicities caused by ICIs based on real-world experience. The cardiac lesion markers are generally unaltered, but it appears that the increased CKMB happened in PD-1 inhibitor groups, but not PDL-1 inhibitor groups.

Interplay Between Gut Microbiota and Amino Acid Metabolism in Heart Failure

Heart failure (HF) is a complex clinical syndrome of which the incidence is on the rise worldwide. Cardiometabolic disorders are associated with the deterioration of cardiac function and progression of HF. Recently, there has been renewed interest in gut microbiota (GM) and its metabolites in the cardiovascular disease. HF-caused hypoperfusion could increase intestinal permeability, and a “leaky” bowel leads to bacterial translocation and make its metabolites more easily enter the circulation. Considerable evidence shows that the composition of microbiota and amino acids (AAs) has been altered in HF patients, and AAs could serve as a diagnostic and prognostic biomarker in HF. The findings indicate that the gut–amino acid–HF axis may play a key role in the progression of HF. In this paper, we focus on the interrelationship between the AA metabolism and GM alterations during the development of heart failure. We also discuss the potential prognostic and therapeutic value of the gut–amino acid–HF axis in the cortex of HF.

Targeted metabolomic analysis of plasma fatty acids in acute myocardial infarction in young adults

BACKGROUND AND AIMS

Acute myocardial infarction (AMI) in young adults has distinct clinical features and risk profile as compared with that in elder adults. The pathophysiologic mechanism of AMI in young adults remains unclear. In this study, we used targeted metabolomics to measure metabolic profile and analyzed plasma fatty acids levels in young adults with AMI, seeking to determine whether circulating fatty acid metabolism was correlated with the occurrence of AMI in young adults.

METHODS AND RESULTS

Consecutive young and elder patients admitted to hospital for AMI were enrolled. Plasma samples of all participants were obtained after overnight fast and then measured using ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS) based targeted metabolomic platform. A total of 201 plasma metabolites were measured using UPLC-MS/MS. Several plasma fatty acids were significantly altered in young AMI patients compared with control or elder AMI patients, which also showed significant prediction value for AMI in young adults. Percentage of short chain fatty acids (SCFAs) was decreased and long chain increased in AMI as compared with control. Moreover, alpha-linolenic acid and linoleic acid metabolism (ALALAM) pathway metabolites were gradually increased in control, young, and elder AMI patients. Altered fatty acid correlation network further identified fatty acid metabolism disorder in AMI in young adults.

CONCLUSION

By utilizing targeted metabolomic technique, we have found several altered fatty acids and respective pathways that show diagnostic value for AMI in young adults. SCFA and long-chain fatty acid (LCFA) were differentially altered in AMI patients.

ARNI versus ACEI/ARB in Reducing Cardiovascular Outcomes after Myocardial Infarction

Aims

This study aimed to compare the efficacy of angiotensin receptor‐neprilysin inhibitor (ARNI) therapy with angiotensin converting enzyme inhibitor or angiotensin receptor blocker (ACEI/ARB) therapy for cardiovascular outcomes in patients with acute myocardial infarction (AMI).

Methods and results

Data were collected from the Biobank of the First Affiliated Hospital of Xi'an Jiaotong University between January 2016 and December 2020. A total of 7556 AMI patients were screened for eligibility. Propensity score matching based on age, sex, blood pressure, kidney function, baseline left ventricular ejection fraction (LVEF), and cardiovascular medication were conducted, resulting in 291 patients with AMI being assigned to ARNI, ACEI, and ARB group, respectively. Patients receiving ARNI had significantly lower rates of the composite cardiovascular outcome than ACEI {hazard ratio [HR] 0.51, [95% confidence interval (CI), 0.27–0.95], P = 0.02}, and ARB users [HR 0.47, (95%CI, 0.24–0.90), P = 0.02]. Patients receiving ARNI showed lower rates of cardiovascular death than ACEI [HR 0.37, (95%CI, 0.18–0.79), P = 0.01] and ARB users [HR 0.41, (95%CI, 0.18–0.95), P = 0.04]. Subgroup analysis indicated that patients with LVEF no more than 40% tend to benefit more from ARNI as compared with ACEI [HR 0.30, (95%CI, 0.11–0.86), P = 0.01] or ARB [HR 0.21, (95%CI, 0.04–1.1), P = 0.05]. Patients aged no more than 60 years exhibited reduced composite endpoints [HR for ARNI vs. ARB: 0.11, (95%CI, 0.03–0.46), P = 0.002].

Conclusions

In patients with AMI, ARNI was superior to ACEI/ARB in reducing the long‐term adverse cardiovascular outcomes. Subgroup analysis further indicates that ARNI is more likely to benefit patients with LVEF less than 40% and aged less than 60 years.

Long-chain noncoding RNA-GAS5/hsa-miR-138-5p attenuates high glucose-induced cardiomyocyte damage by targeting CYP11B2

OBJECTIVE

Diabetic cardiomyopathy (DCM) is one of the complications experienced by patients with diabetes. In recent years, long noncoding RNAs (lncRNAs) have been investigated because of their role in the progression of various diseases, including DCM. The purpose of the present study was to explore the role of lncRNA GAS5 in high glucose (HG)-induced cardiomyocyte injury and apoptosis.

MATERIALS AND METHODS

We constructed HG-induced AC16 cardiomyocytes and a streptozotocin (STZ)-induced rat diabetes model. GAS5 was overexpressed and knocked out at the cellular level, and GAS5 was knocked down by lentiviruses at the animal level to observe its effect on myocardial injury. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to detect the expression of GAS5. Cell proliferation and apoptosis after GAS5 knockout were detected by CCK-8, TUNEL, and flow cytometry assays. ELISA was used to detect the changes in myocardial enzyme content in cells and animal myocardial tissues during the action of GAS5 on myocardial injury.

RESULTS

GAS5 expression was up-regulated in HG-treated AC16 cardiomyocytes and the rat diabetic myocardial injury model. The down-regulation of GAS5 could inhibit HG-induced myocardial damage. This work proved that the down-regulation of GAS5 could reverse cardiomyocyte injury and apoptosis by targeting miR-138 to down-regulate CYP11B2.

CONCLUSION

We confirmed for the first time that the down-regulation of GAS5 could reverse CYP11B2 via the miR-138 axis to reverse HG-induced cardiomyocyte injury. This research might provide a new direction for explaining the developmental mechanism of DCM and potential targets for the treatment of myocardial injury.

Impact of Age, Sex, and Renal Function on the Efficacy and Safety of Direct Oral Anticoagulants vs. Vitamin K Antagonists for the Treatment of Acute Venous Thromboembolism: A Meta-Analysis of 22,040 Patients

Objective: In this study, we conducted a meta-analysis to assess the impact of age, sex, and renal function on the efficacy and safety of direct oral anticoagulants (DOACs) vs. vitamin K antagonists (VKAs) for the treatment of acute venous thromboembolism (VTE).

Methods: Electronic databases (accessed till June 2021) were systematically searched to investigate randomized clinical trials evaluating apixaban, dabigatran, edoxaban, and rivaroxaban vs. VKAs for the treatment of acute VTE. Results were presented as odds ratio (OR) and 95% CIs.

Results: Direct oral anticoagulants were associated with a borderline higher efficacy in women (OR: 0.79, 95% CI: 0.62–1.02), a significantly higher efficacy in patients with age more than 75 years (OR: 0.51, 95% CI: 0.32–0.80), and creatinine clearance <50 ml/min (OR: 0.57, 95% CI: 0.32–0.99). The primary safety endpoint of major or clinically relevant non-major bleeding was significantly reduced in DOACs as compared to VKAs in both patients with age <75 years (OR: 0.79, 95% CI: 0.70–0.89) and patients with age more than 75 years (OR: 0.75, 95% CI: 0.59–0.96). DOACs also show an advantage in terms of major or clinically relevant non-major bleeding in men (OR: 0.72, 95% CI: 0.60–0.86) and patients with creatinine clearance of more than 50 ml/min (OR: 0.75, 95% CI: 0.67–0.84).

Conclusions: Direct oral anticoagulants have exhibited clinical preference among patients with acute VTE with decreased thrombosis and bleeding events, especially in patients with age more than 75 years and creatinine clearance <50 ml/min.

Circulating lipid and lipoprotein profiles and their correlation to cardiac function and cardiovascular outcomes in patients with acute myocardial infarction

Recent studies showed that lipoproteins represent major risk factors, both positive and negative, for atherosclerotic cardiovascular disease. The aim of the present study was to describe the relationship between plasma lipid profile and cardiac function and cardiovascular outcomes in patients with acute myocardial infarction (AMI) after percutaneous coronary intervention (PCI). Two independent groups of subjects including a total of 797 patients diagnosed of AMI undergoing PCI admitted to the First Affiliated Hospital of Xi’an Jiaotong University were included in the present study. We performed a cross-sectional study for the correlation between plasma lipid profile and cardiac function based on the first group, including 503 patients with AMI. We further validated the correlation and did the follow-up of 2.4 years of major cardiovascular outcomes on the second group, including 294 patients with AMI. Our results showed that apolipoprotein A-I (ApoA-I) level was significantly reduced, and the high-density lipoprotein cholesterol (HDL-C):ApoA-I ratio was increased in the patients with lower LVEF or higher N-terminal pro-B-type natriuretic peptide levels compared with the control; there was a positive correlation between cardiac function and ApoA-I, and a negative correlation between cardiac function and the HDL-C:ApoA-I ratio. Meanwhile, multivariate Cox analysis showed that ApoA-I was independent predictors of major adverse cardiovascular events (MACEs). Kaplan-Meier survival analysis showed the ApoA-I levels exhibited a significant effect on predicting the incidence of MACEs. In sum, plasma ApoA-I level is positively associated with the cardiac function of patients with AMI after PCI, and ApoA-I is an independent indicator to predict the incidence of MACEs.

The gut microbiota is associated with clinical response to statin treatment in patients with coronary artery disease

BACKGROUND

The structure and composition of the gut microbiota influence patients' response to therapeutic interventions. It is also known that the response to statin treatment can vary greatly from one patient to another, suggesting a possible connection between microbiome composition and response to statins. In the present study, we aim to explore the influence of the microbiome composition on the response to statin treatment among patients with coronary artery disease (CAD).

METHODS

A prospective cohort of 836 CAD patients enrolled from January 2016 to December 2017 was used to perform a nested case-control study. We divided 110 CAD patients into two groups according to their response to statins (good response group and poor response group) and compared their gut microbiota.

RESULTS

Our analysis reveals no significant difference in microbiome between the two groups. However, significant differences were found in the relative proportion of numerous genera between GR and PR groups. Most remarkably, we could observe that a poor response to statin treatment correlates to a significant decrease in the abundance of beneficial bacteria for the lipid metabolism (Akkermansia muciniphila (A. muciniphila) and Lactobacillus) and a significant increase in the abundance of bacteria (Holdemanella and Facecallibacterium).

CONCLUSIONS

Gut microbiota structure is associated with the response to statin. Our results suggest that manipulation of the gut microbiota composition can be an interesting and effective treatment strategy to blood lipid control among CAD patients.

Different associations between left atrial size and 2.5-year clinical outcomes in patients with anterior versus non-anterior wall ST-elevation myocardial infarction

Objective

To investigate associations between left atrial diameter (LAD) and long-term outcomes in patients with anterior or non-anterior wall ST-elevation myocardial infarction (STEMI).

Methods

Patients with STEMI were included in this secondary analysis of data from a prospective cohort study in which the primary outcome was major adverse cardiovascular event (MACE) occurrence during a 2.5-year follow-up. A LAD cut-off value was obtained through receiver operating characteristic curve analysis. Kaplan-Meier curve and Cox regression analyses were applied. Subgroup Cox regression analysis was also performed, with patients stratified based on left ventricular diastolic diameter (LVEDD, > 55 mm and ≤55 mm). The relationship between LAD and outcomes in patients with anterior or non-anterior wall STEMI was explored using restricted cubic spline functions.

Results

Out of 464 patients, adjusted Cox regression showed that dichotomous (>40 mm) LAD was significantly associated with MACE (hazard ratio 2.978, 95% confidence interval 1.763, 5.030) in patients with anterior wall but not non-anterior wall STEMI. The association was not different between normal and enlarged LVEDD groups.

Conclusions

A left atrium > 40 mm may indicate higher risk of MACE in patients with anterior wall STEMI, even in patients with normal left ventricular structure. This relationship was not observed in patients with non-anterior wall STEMI.

Coexistent pulmonary cryptococcal infection and pulmonary sarcoidosis: a case report and literature review

Cryptococcus is an encapsulated, yeast-like fungus commonly responsible for infections in individuals with impaired T cell-mediated immune responses, including those with acquired immune deficiency syndrome or taking immunosuppressive agents such as steroids or cyclosporine. However, pulmonary fungal infection is rare in patients with untreated sarcoidosis. We report a case of coexistent pulmonary cryptococcal infection in a 43-year-old man with pulmonary sarcoidosis in North-western China. The patient was diagnosed with sarcoidosis via right anterior mediastinal lymph node biopsy and lung biopsy by bronchoscopy. He was treated with oral prednisone 25 mg/day and achieved complete remission of all symptoms. However, repeat chest computed tomography examination revealed enlarged nodules in the left lower lobe, but decreased bilateral diffuse small nodules in the lungs. Computed tomography-guided percutaneous lung puncture biopsy revealed cryptococcal infection. This case highlights the need to consider fungal infection in patients with sarcoidosis at initial presentation, irrespective of their use of immunosuppressive medication.

Duration of Viral Shedding of Discharged Patients With Severe COVID-19

The 2019 coronavirus disease (COVID-19) has drawn global intensive attention^1-3. Most of studies paid attention to epidemiological, clinical, and radiological features of inpatients with COVID-19^1-3. However, little studies have focused on clinical characteristics of discharged patients with severe COVID-19, especially the duration of viral shedding.

Altered exosomal microRNA profiles in bronchoalveolar lavage fluid can mediate metabolism in patients with Acinetobacter baumannii ventilator-associated pneumonia

Background

Ventilator-associated pneumonia (VAP) is a major public health problem and is most commonly caused by Acinetobacter baumannii (Ab) infection. In our study, we investigated the profiles of exosomal microRNAs (miRNAs) extracted from the bronchoalveolar lavage fluid (BALF) and serum of patients with Acinetobacter baumannii ventilator-associated pneumonia (Ab-VAP). We also examined the serum metabolomic profiles of these patients. Our aim was to study the associations between lung tissue-derived exosomal miRNAs and changes in global metabolism in patients with Ab-VAP.

Methods

Consecutively sampled patients admitted to an intensive care unit (ICU) for pulmonary infection treatment were enrolled in this study. Demographic information and biochemical measurements were collected. Serum samples were obtained following overnight fasting on admission. Bronchoscopies were performed and BALF samples were collected from each patient. Exosomes were extracted using kits from System Biosciences (SBI) and miRNA sequencing was performed. Non-targeted metabolomics were used to express metabolic profiles.

Results

We found significant changes in the miRNA profiles of patients with Ab-VAP; these changes occurred in both BALF exosomal miRNA and serum exosomal miRNA. Gene Ontology analysis further identified the function of miRNA in system metabolism. Serum metabolomic profiles and ratios of biological significance were found to be differentially regulated in Ab-VAP patients. This differential regulation was correlated with the differential expression of miRNAs.

Conclusions

Our data summarizes the dysregulation of serum metabolism and exosomal miRNA excretion that occurs in Ab-VAP patients. The correlation found between BALF exosomal miRNA and dysregulated metabolism, as indicated by the irregular expression of metabolites in the cellular metabolic pathway, highlights potential biomarkers for the diagnosis and treatment of Ab infection.

Meta-analysis comparing impact of age, sex and renal function on the efficacy and safety of new oral anticoagulants vs. vitamin K antagonists for the treatment of acute venous thromboembolisms

Background

New direct oral anticoagulants (NOACs), as a preferable treatment option for acute venous thromboembolism (VTE) have been recommended with practical advantages as compared to Vitamin K antagonists (VKAs) in clinical practice.

Purpose

In our study, we performed a meta-analysis to determine the efficacy and safety of NOACs vs. VKAs in patients with different age, sex and renal function for the treatment of VTE.

Methods

Electronic databases (accessed October 2019) were systematically searched to identify RCTs evaluating apixaban, dabigatran, edoxaban, and rivaroxaban versus VKAs for the treatment of acute venous thromboembolism.

Results

NOACs was associated with a borderline higher efficacy in female (OR 0.79, 95% CI 0.62–1.02), and a significantly higher efficacy in patients with age more than 75 (OR 0.51, 95% CI 0.32–0.80) and creatinine clearance less than 50 mL/min (OR 0.57, 95% CI 0.32–0.99). NOACs also show advantage in terms of major or clinically relevant non-major bleeding in male (OR 0.72, 95% CI 0.60–0.86), and patients with creatinine clearance more than 50 mL/min (OR 0.75, 95% CI 0.67–0.84).

Conclusions

NOACs have exhibited clinical preference among patients with acute VTE as compared to VKA with significantly decreased thrombosis events and lower bleeding complications, especially in patients with age more than 75 and creatinine clearance less than 50 mL/min.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): This study was supported by the National Natural Science Foundation of China (81800390) and the Natural Science Foundation of Shaanxi province (2018KW067).

Serum lipids profiling perturbances in patients with ischemic heart disease and ischemic cardiomyopathy

Background

Ischemic heart disease (IHD) is a common cardiovascular disorder associated with inadequate blood supply to the myocardium. Chronic coronary ischemia leads to ischemic cardiomyopathy (ICM). Despite their rising prevalence and morbidity, few studies have discussed the lipids alterations in these patients.

Methods

In this cross-sectional study, we analyzed serum lipids profile in IHD and ICM patients using a lipidomics approach. Consecutive consenting patients admitted to the hospital for IHD and ICM were enrolled. Serum samples were obtained after overnight fasting. Non-targeted metabolomics was applied to demonstrate lipids metabolic profile in control, IHD and ICM patients.

Results

A total of 63 and 62 lipids were detected in negative and positive ion mode respectively. Among them, 16:0 Lyso PI, 18:1 Lyso PI in negative ion mode, and 19:0 Lyso PC, 12:0 SM d18:1/12:0, 15:0 Lyso PC, 17:0 PC, 18:1–18:0 PC in positive ion mode were significantly altered both in IHD and ICM as compared to control. 13:0 Lyso PI, 18:0 Lyso PI, 16:0 PE, 14:0 PC DMPC, 16:0 ceramide, 18:0 ceramide in negative ion mode, and 17:0 PE, 19:0 PC, 14:0 Lyso PC, 20:0 Lyso PC, 18:0 PC DSPC, 18:0–22:6 PC in positive ion mode were significantly altered only in ICM as compared to IHD and control.

Conclusion

Using non-targeted lipidomics profiling, we have successfully identified a group of circulating lipids that were significantly altered in IHD and ICM. The lipids metabolic signatures shed light on potential new biomarkers and therapeutics for preventing and treating ICM.

A Case of Coronavirus Disease 2019 With Concomitant Acute Cerebral Infarction and Deep Vein Thrombosis

We report a case of a 75-year-old woman diagnosed with severe coronavirus disease 2019 (COVID-19) complicated by acute cerebral infarction. The patient was admitted to our hospital on 5 February 2020 with severe COVID-19. On 20 February 2020, she was diagnosed with concomitant acute cerebral infarction via head computed tomography (CT) and deep vein thrombosis in both lower limbs. After symptomatic and supportive treatments, the patient was discharged on 13 March 2020. She will comply with quarantine for another 2 weeks and receive rehabilitation training from a specialist doctor. Cerebral infarction should be considered and promptly managed in patients with COVID-19.

Dysregulated serum lipid profile and its correlation to disease activity in young female adults diagnosed with systemic lupus erythematosus: a cross-sectional study

BACKGROUND

Recent studies showed that dyslipidemia could be a critical factor in the progression of cardiovascular disease in systemic lupus erythematosus (SLE). The aim of the present study was to describe the relationship between serum lipid profile and SLE disease activity in young female adults with SLE.

METHODS

Seventy-one female subjects diagnosed with SLE aged 20~30 years were enrolled. Serum lipid profile including TC, TG, HDL-C, LDL-C, VLDL-C, Apo A, Apo B, and Apo E were evaluated between control and young female SLE patients. Univariate correlation analyses were performed to explore the correlation between serum lipid levels and SLE disease activity.

RESULTS

Our results showed that TG and VLDL-C levels were significantly increased in young female SLE as compared to control, with TC, HDL-C, LDL-C, Apo A, and Apo B significantly reduced. Meanwhile, univariate correlation analyses showed negative correlations between SLE disease activity index and HDL-C, LDL-C, Apo A, and Apo B; with positive correlations between SLE disease activity index and TG and VLDL-C.

CONCLUSION

Serum lipid profile was significantly dysregulated in young female SLE patients. Moreover, SLE disease activity was correlated to the serum lipid levels, supporting the notion that the young patients with SLE might also have a higher risk of cardiovascular disease.

Piperine, a functional food alkaloid, exhibits inhibitory potential against TNBS-induced colitis via the inhibition of IκB-α/NF-κB and induces tight junction protein (claudin-1, occludin, and ZO-1) signaling pathway in experimental mice

BACKGROUND

Inflammatory bowel disease is a chronic immunoinflammatory disease of the gastrointestinal tract. Piperine, an alkaloid, has been reported to possess antioxidant, anti-inflammatory, antiapoptotic, and antiulcer potential.

AIM

To elucidate the plausible mechanisms of action of piperine on experimental trinitrobenzenesufonic acid (TNBS)-induced colitis by assessing various biochemical, molecular, histological, and ultrastructural modifications.

METHODS

Colitis was induced in male Sprague-Dawley rats via intrarectal instillation of TNBS. Then, the rats were treated with piperine (10, 20, and 40 mg/kg, p.o.) for 14 days.

RESULTS

TNBS induced significant (p < 0.05) colonic damage, which was assessed by disease activity index, macroscopic score, and stool consistency. The administration of piperine (20 and 40 mg/kg) significantly inhibited (p < 0.05) these damages. Treatments with piperine (20 and 40 mg/kg) notably inhibited (p < 0.05) the TNBS-induced elevation of oxido-nitrosative stress (superoxide dismutase, glutathione, malondialdehyde, and nitric oxide), 5-hydroxytryptamine, and hydroxyproline content in the colon. Furthermore, colonic inducible nitric oxide synthase (iNOs), tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1β, IL-6, interferon-gamma, and cyclooxygenase-2 (COX-2) messenger RNA (mRNA) expressions were upregulated after TNBS instillation and piperine (20 and 40 mg/kg) significantly attenuated (p < 0.05) these elevated mRNA expressions. TNBS decreased the expressions of tight junction (TJ) protein (claudin-1, occludin, and zonula occludens-1 (ZO-1)) and increased the expressions of proapoptotic (caspase-1) protein. These expressions were markedly inhibited (p < 0.05) by piperine treatment. Histological and ultrastructural studies of transmission electron microscopy suggested that piperine significantly ameliorated (p < 0.05) TNBS-induced colonic aberrations.

CONCLUSION

Piperine ameliorated the progression of TNBS-induced colitis by modulating the nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor-alpha/nuclear factor-kappa B signaling pathway, thus inhibiting the overexpression of proinflammatory cytokines (TNF-α and IL's), COX-2, iNOs, oxido-nitrosative stress, and proapoptotic proteins (caspase-1) that may improve the expression of TJ protein (claudin-1, occludin, and ZO-1).

Applying sinus node function testing to evaluate perioperative management for patients suffering from tachycardia-bradycardia syndrome before atrial fibrillation ablation

Sinus node (SN) function is an important prognostic factor of atrial fibrillation (AF). However, AF ablation guideline has not recommended SN function test before ablation. SN function testing before AF ablation in patients with tachycardia-bradycardia syndrome should be beneficial to determine further therapy strategies and prognosis.

[Renal clear cell carcinoma transferred to infratemporal fossa and pterygopalatine fossa: A case report]

SummaryRenal clear cell carcinoma is prone to distant metastasis, especially in the head and neck, but it is rare to transfer to infratemporal fossa and pterygopalatine fossa. We reported a 62-year-old male patient with complains of numbness and burning sensation on the left side of the face for more than 3 months. Left kidney removal was performed 8 years ago due to renal cancer. Preoperative enhancement CT showed a large blood-rich occupation in the left nasopharyngeal and pterygopalatine with adjacent paranasal sinus and skull base bone destruction. Under the general anesthesia, the anterior lacrimal recess approach was used for tumor resection. Preoperative interventional embolization of the feeding artery, intraoperative pathology, frozen section showed metastasis of renal cell carcinoma, and postoperative immunohistochemical examination, confirmed metastatic renal clear cell carcinoma（infratemporal fossa and pterygopalatine fossa）. The patients were transferred to the oncology department for further radiotherapy and chemotherapy.

Genetic compensation by epob in pronephros development in epoa mutant zebrafish

Zebrafish erythropoietin a (epoa) is a well characterized regulator of red blood cell formation. Recent morpholino mediated knockdown data have also identified epoa being essential for physiological pronephros development in zebrafish, which is driven by blocking apoptosis in developing kidneys. Yet, zebrafish mutants for epoa have not been described so far. In order to compare a transient knockdown vs. permanent knockout for epoa in zebrafish on pronephros development, we used CRISPR/Cas9 technology to generate epoa knockout zebrafish mutants and we performed structural and functional studies on pronephros development. In contrast to epoa morphants, epoa^-/- zebrafish mutants showed normal pronephros structure; however, a previously uncharacterized gene in zebrafish, named epob, was identified and upregulated in epoa^-/- mutants. epob knockdown altered pronephros development, which was further aggravated in epoa^-/- mutants. Likewise, epoa and epob morphants regulated similar and differential gene signatures related to kidney development in zebrafish. In conclusion, stable loss of epoa during embryonic development can be compensated by epob leading to phenotypical discrepancies in epoa knockdown and knockout zebrafish embryos.

Clinical characteristics and protective factors in patients with acute myocardial infarction undergoing in-hospital myocardial free wall rupture: a single-center, retrospective analysis

Myocardial free wall rupture (MFWR) refers to laceration of the heart ventricle or atria, which is a rare but fatal complication of acute myocardial infarction (AMI). In this study, we aim to identify the clinical characteristics and protective factors of free wall rupture after myocardial infarction. This is a single-center, retrospective observational analysis. The study screened all patients admitted to the cardiology department of the First Affiliated Hospital of Xi'an Jiaotong University between January 2013 and April 2018. The biochemical, clinical, angiographic and echocardiographic features of these patients were then collected and analyzed. Among the 5946 screened patients with AMI, 23 patients with a diagnosis of MFWR after AMI were enrolled in the present study. 18 (78.3%) patients were diagnosed with acute ST segment elevated myocardial infarction and the remaining 5 (21.7%) have acute non-ST segment elevated myocardial infarction. Early-phase MFWR happened in 12 (52.2%) and late-phase accounted for 8 (34.8%) in total. Late-phase MFWR had lower left ventricle ejection fraction value (45.8%±5.6% vs 63.0±3.8%, p<0.001) as compared with early-phase. Patients who survived from MFWR has higher ACE inhibitor/angiotensin II receptor blocker (ACEI/ARB) and β-blocker coverage in the in-hospital treatment of AMI (ACEI/ARB: 100.0% vs 35.3%, p=0.014; β-blocker: 100.0% vs 47.1%, p=0.048). The present study provides evidence for better understanding of the clinical characteristics and protective functions in MFWR after AMI. Reduced cardiac function is correlated with higher incidence of later phase free wall rupture. Higher ACEI/ARB and β-blocker coverage in the AMI treatment strategy is associated with lower MFWR incidence.

Targeting erythropoietin protects against proteinuria in type 2 diabetic patients and in zebrafish

Objective

Adult human kidneys produce erythropoietin (EPO), which regulates red blood cell formation; however, whether EPO also functions directly on kidney development and controls diabetic kidney disease remains unknown. Here we analyzed the role of EPO in kidney development and under hyperglycemic conditions in zebrafish and in humans.

Methods

Diabetic patients and respective controls were enrolled in two cohorts. Serum EPO level and urine protein change upon human EPO administration were then analyzed. Transient knockdown and permanent knockout of EPO and EPOR in renal TG(WT1B:EGFP) zebrafish were established using the morpholino technology and CRISPR/Cas9 technology. Zebrafish embryos were phenotypically analyzed using fluorescence microscopy, and functional assays were carried out with the help of TexasRed labeled 70 kDa Dextran. Apoptosis was determined using the TUNEL assay and Annexin V staining, and caspase inhibitor zVADfmk was used for rescue experiments.

Results

In type 2 diabetic patients, serum EPO level decreased with the duration of diabetes, which was linked to reduced kidney function. Human recombinant EPO supplementation ameliorated proteinuria in diabetic nephropathy patients. In zebrafish, loss-of-function studies for EPO and EPOR, showed morphological and functional alterations within the pronephros, adversely affecting pronephric structure, leading to slit diaphragm dysfunction by increasing apoptosis within the pronephros. Induction of hyperglycemia in zebrafish embryos induced pronephros alterations which were further worsened upon silencing of EPO expression.

Conclusions

EPO was identified as a direct renal protective factor, promoting renal embryonic development and protecting kidneys from hyperglycemia induced nephropathy.

•

EPO exhibited renal protective and proteinuria ameliorating function in type 2 DM patients and in hyperglycemic zebrafish embryos.

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Enhanced co-expression of EPO and EPOR was identified in both glomeruli and tubuli of DN patients.

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EPO and its receptor directly regulate physiological kidney development via repressing apoptosis.

Hemoglobin A1c is associated with severity of coronary artery stenosis but not with long term clinical outcomes in diabetic and nondiabetic patients with acute myocardial infarction undergoing primary angioplasty

Background

Acute myocardial infarction (AMI) patients with type 2 diabetes mellitus are known to present with multiple vessel lesions during coronary angiography. The underlying mechanism remains elusive and there is a shortage of serum prediction markers. In this study, we investigate the relationship between admission HbA_1c and severity of coronary artery stenosis and subsequent prognosis in AMI patients with or without diabetes.

Research design and methods

We measured admission HbA_1c, and vessel scores based on the number of diseased coronary vessels with significant stenosis in 628 patients diagnosed with AMI. Simple and multi-regression analysis were performed to investigate the correlation between HbA_1c and the severity of coronary artery stenosis. Major adverse cardiovascular events (MACE), including new-onset myocardial infarction, acute heart failure and cardiac death, were documented during the follow-up. 272 non-DM participants and 137 DM participants were separated into two groups based on HbA_1c levels for survival analysis during a 2-year follow up.

Results

448 non-DM patients and 180 DM patients were included in the initial observational analysis. 272 non-DM patients and 137 DM patients were included in the follow-up survival analysis. The admission HbA_1c level was found to be significantly positively correlated to the number of affected vessels suffering from significant coronary artery stenosis both in DM (R square = 0.012; 95% CI 0.002 to 0.623, P = 0.049) and non DM patients (R square = 0.025; 95% CI 0.009 to 0.289, P = 0.037). Kaplan–Meier survival analysis revealed no significant difference with regard to different HbA_1c levels either in DM or non-DM patients at the end of follow-up.

Conclusions

In patients with AMI, admission HbA_1c is an important predictor for the severity of coronary artery stenosis in non-DM and DM patients. Further studies are needed to determine whether longer term follow-up could further identify the prognosis effect of HbA_1c on MACE.

Chest Pain after Aortic Valve Replacement: Rupture of Right Sinus of Valsalva Presenting as Myocardial Infarction

Background: A 47-year-old male presented with retrosternal chest pain, which had started 4 days previously and had become excruciating for the past 6 h. He had undergone mechanical aortic valve replacement surgery 4 months previously. Investigation: Electrocardiography, echocardiography, computed tomography-angiography of the aorta. Diagnosis: Rupture of the right sinus of Valsalva and right coronary artery dissection. Management: The defect in the right coronary sinus was closed, and the dissection at the root of the right coronary artery was resected and the right coronary artery bypassed to the root of the aorta.

Clinical observation of atrial threshold monitoring algorithm: a single center experience

OBJECTIVE

To observe the atrial capture management in an atrial threshold monitoring algorithm. By calculating the enabling rate of the atrial threshold monitoring algorithm and comparing atrial thresholds measured automatically and manually, we evaluate its safety, reliability and applicability in clinical practice.

METHODS AND RESULTS

Data were collected at implant, start of atrial threshold monitoring, visits scheduled 1 month, 2 months and 4 months thereafter, and upon notification of adverse events. Atrial threshold monitoring algorithm was enabled in 94 patients, while in 38 not, indicating an enabling rate of 71.2%. Causes of the unsuccessful attempts to enable automatic atrial threshold include tachycardia (2, 5.3%), and atrial safety margin not met (36, 94.7%). A total of 88 pairs of atrial thresholds measured automatically and manually were gained. The auto threshold was 0.528 ± 0.270 V, and the manual threshold was 0.580 ± 0.223 V. There is a strict correlation between the automatic measurements and those conducted manually by the physician with a P < 0.05. No significant differences were observed during the 1-month, 2-month and 4-month follow-up.

CONCLUSION

Atrial threshold monitoring algorithm is safe, reliable and applicable over time. Atrial threshold monitoring tested atrial threshold was demonstrated to be clinically equivalent to the manual atrial threshold test. The addition of atrial threshold monitoring will benefit the patients by reducing energy cost and enhancing pacemaker safety.

DETECTION OF LACTOBACILLI IN MONTHLY MAIL-IN STOOL SAMPLES FROM 3-18 MONTHS OLD INFANTS AT GENETIC RISK FOR TYPE 1 DIABETES

The feasibility to detect lactobacilli in mail-in infant stools collected monthly from 3-18 months old children was investigated. The aim was to determine total lactobacilli and Lactobacillus plantarum (L. plantarum) content (ng/g feces) in 50 infants each from Colorado (648 samples), Finland (624 samples) and Sweden (685 samples) who participated in the TEDDY (The Environmental Determinants of Diabetes in the Young) study. Total lactobacilli content varied markedly between 5 and 16,800 ng/g feces in the three clinical sites within and between individuals especially in infants. L.plantarum also varied markedly intra- and inter-individually from <0.5 - 736 ng/g feces. A higher variability of total lactobacilli was found before 10 months of age than after in the three different clinical sites. Sweden had the lowest total lactobacilli content compared to Colorado and Finland while the L.plantarum content was higher in Sweden. Mail-in stool samples from infants should prove useful in analyzing probiotics in childhood.

Stress failure plays a major role in the development of high-altitude pulmonary oedema in rats

Hypoxia and exertion are considered as the two main factors in the development of high-altitude pulmonary oedema (HAPE), however its pathophysiology remains unclear. Therefore, we established a model in which 32 Sprague-Dawley rats were randomly assigned to normoxic rest, hypoxic rest, normoxic exercise and hypoxic exercise. An altitude of 4,700 m was simulated using hypobaric hypoxia, while exercise consisted 48 h walk with 15-20 min breaks every 4 h. Arterial blood gas, bronchoalveolar lavage (BAL), lung wet-to-dry weight (W/D) ratio and histological measurements were conducted on each animal. In rats exercising in hypoxia, BAL protein and lung W/D ratio were significantly increased but no changes in BAL leukotriene B(4) and immunoglobulin M were observed. In the same group, lung histology showed typical haemorrhagic lung oedema and disruption of both alveolar epithelium and capillary endothelium while hypoxia or exertion alone only induced slight endothelium and epithelium swelling/disruption. Our study established a direct link between histological and physiological evidence of HAPE-like symptoms and we demonstrated that hypoxia and exertion can synergistically induce HAPE-like symptoms in Sprague-Dawley rats without inducing lung inflammation. We therefore propose that alveolar epithelium and capillary endothelium stress failure play a major role in the development of HAPE.

Improving auscultatory blood pressure measurement with electronic and computer technology: the visual auscultation method

BACKGROUND

The auscultatory method is used as the reference standard in all prevalent protocols for validation of noninvasive blood pressure measuring devices, and a validation study is essentially based on the comparison between the device and observer measurements. Thus, the objectivity and accuracy of observer measurements are crucial to the validation result.

METHODS

To provide observers with more objective information about an auscultatory measurement so that sufficient information to make measurements with greater potential objectivity and accuracy can be available, a computerized data acquisition and analysis system has been developed. It cannot only acquire and store Korotkoff sound, cuff pressure, and oscillometric pulse signals, as well as the sphygmomanometer image, but it also can display the waveforms of the three signals and the sphygmomanometer video while playing the synchronous Korotkoff sounds. With this system, observers can make their measurements via the visual auscultation method, that is to say, by watching those waveforms, instead of the sphygmomanometer, while listening for synchronized Korotkoff sounds. The system was validated according to the International Protocol (IP).

RESULTS

The result showed that all the differences between system measurements by the visual auscultation method and observer measurements by the conventional auscultatory method were within 4 mm Hg.

CONCLUSIONS

The visual auscultation method achieved a high degree of accuracy, and human observers can be replaced by the system in the validation study of blood pressure measuring devices.

Early chronic aluminium exposure impairs long-term potentiation and depression to the rat dentate gyrus in vivo

As an important neurotoxin, aluminium can cause cognitive dysfunctions and mental diseases. Previous studies have reported that aluminium impaired long-term potentiation (LTP) in vivo and in vitro. Here, we utilise two models of synaptic plasticity, LTP and long-term depression (LTD) to study the effects of aluminium on synaptic plasticity in vivo. Neonatal Wistar rats were chronically exposed to aluminium from birth to weaning via the milk of dams fed with 0.3% aluminium chloride solution. Excitatory postsynaptic potential (EPSP) and population spikes (PS) were recorded from the dentate gyrus (DG) of adult rats by electrically stimulating the perforant path. THE FOLLOWING RESULTS WERE OBTAINED: (1) The input/output function indicated that, as compared to controls, aluminium increased the baseline amplitude of the PS, but decreased the baseline slope of EPSP. (2) Aluminium significantly prevented LTD in PS (controls: 77.36+/-6.7%, n=7; aluminium-exposed: 102.01+/-9.1%, n=7; P<0.05) and decreased the LTD amplitude in EPSP (controls: 76.61+/-4.1%, n=7; aluminium-exposed: 94.31+/-7.9% n=7, P<0.05). (3) Aluminium reduced the amplitude of LTP in both PS (controls: 190+/-16.1%, n=7; aluminium-exposed: 135+/-9.7%, n=7; P<0.05) and EPSP (control: 132+/-9.3%, n=7; aluminium-exposed: 115+/-10.6%, n=7; P<0.05). As for LTD and LTP, PS was impaired more seriously than EPSP in aluminium-exposed rats. (4) Aluminium exposure decreased the paired-pulse facilitation (PPF) of PS at 30-150 ms interpulse interval (IPI), and reduced 93.5% of PPF at 80 ms IPI in PS (controls: 243.4+/-39.8%, n=7; aluminium-exposed: 149.9+/-12.3%, n=7). There was no significant difference in EPSP of PPF. From these results we conclude that aluminium exposure in neonatal rats thus reduces the amplitude of LTP and PPF and blocks the induction of LTD in the DG. We suggest that aluminium affects both presynaptic and postsynaptic mechanisms of synaptic transmission.

Inhibitory effects of sodium quercetin monosulfate on pig platelet aggregation induced by thrombin

AIM

To study the inhibitory effects of sodium quercetin monosulfate (SQMS) on pig platelet aggregation induced by thrombin.

METHODS

Platelet aggregation was analyzed by turbidimetry. Cytosolic free calcium concentration ([Ca2+]i) was determined by Fura-2 fluorescence. Activity of protein kinase C (PKC) was assayed by incubating PKC with histone III S and [gamma-32 P] ATP. The cytoskeletal proteins were precipitated by Triton X-100 and separated by SDS-PAGE.

RESULTS

SQMS inhibited the platelet aggregation induced by thrombin 500 U.L-1 with IC50 132 (50-347) mumol.L-1. SQMS inhibited Ca2+ influx in blood platelets induced by thrombin 500 U.L-1 in the presence of extracellular Ca2+ 1 mmol.L-1 with IC50 20 (9-46) mumol.L-1; SQMS inhibited the internal Ca2+ release in the absence of extracellular Ca2+. SQMS also decreased [Ca2+]i level in quiescent blood platelets. SQMS (10-160 mumol.L-1) inhibited the activity of cytosolic PKC from blood platelets in a concentration-dependent manner, but had no effect on membrane PKC. SQMS (20-80 mumol.L-1) inhibited the actin polymerization induced by thrombin 500 U.L-1 inblood platelets in a concentration-dependent manner.

CONCLUSION

SQMS inhibited pig platelet aggregation induced by thrombin and its mechanism might be due to its inhibitions of Ca2+ influx, internal Ca2- release, PKC activity, and actin polymerization.