RNA extraction-free reduced graphene oxide-based RT-LAMP fluorescence assay for highly sensitive SARS-CoV-2 detection.

Infectious diseases have always been a seriously endanger for human life and health. A rapid, accurate and ultra-sensitive virus nucleic acid detection is still a challenge to deal with infectious diseases. Here, a RNA extraction-free reduced graphene oxide-based reverse transcription-loop-mediated isothermal amplification (EF-G-RT-LAMP) fluorescence assay was developed to achieve high-throughput, rapid and ultra-sensitive SARS-CoV-2 RNA detection. The whole detection process only took ∼36 min. The EF-G-RT-LAMP assay achieves a detection limit of 0.6 copies µL-1 with a wide dynamic range of aM-pM. A large number (up to 384) of samples can be detected simultaneously. Simulated detection of the COVID-19 pseudovirus and clinical samples in nasopharyngeal swabs demonstrated a high-throughput, rapid and ultra-sensitive practical detection capability of the EF-G-RT-LAMP assay. The results proved that the assay would be used as a rapid, easy-to-implement approach for epidemiologic diagnosis and could be extended to other nucleic acid detections.

Case report: Different clinical manifestations of the rare Loeffler endocarditis.

Background: Loeffler endocarditis is a rare and fatal disease, which is prone to be misdiagnosed, owing to its various clinical manifestations. Consequently, an early identification of Loeffler endocarditis and its effective treatment are crucial steps to be undertaken for good prognosis. Case presentation: This report describes two cases of Loeffler endocarditis with different etiologies and clinical manifestations. Case 1 was caused by idiopathic eosinophilia and presented with a thrombus involving the tricuspid valve and right ventricular inflow tract (RVIT). The patient suffered from recurrent syncope following activity. After the patient underwent tricuspid valve replacement and thrombectomy, he took oral prednisone and warfarin for 2 years, consequent to which he discontinued both drugs. However, the disease recurred 6 months later, this time manifesting as edema of both legs. Echocardiography showed that a thrombus had reappeared in the RVIT. Thus, oral prednisone and warfarin therapy was readministered. Three months later, the thrombus had dissolved. Low-dose prednisone maintenance therapy was provided long term. Case 2 involved a patient who presented with recurrent fever, tightness in the chest, and asthma, and whose condition could not be confirmed, despite multiple local hospitalizations. In our hospital, echocardiography revealed biventricular apical thrombi. After comprehensive examinations, the final diagnosis was eosinophilic granulomatosis polyangiitis (EGPA) involving multiple organs, including the heart (Loeffler endocarditis), lungs, and kidneys. After administration of corticosteroid, anticoagulant, and immunosuppressive agents along with drugs to improve cardiac function, the patient's symptoms improved significantly. Conclusion: In Loeffler endocarditis due to idiopathic eosinophilia, long-term corticosteroid use may be required. Diverse and non-specific symptoms cause Loeffler endocarditis to be easily misdiagnosed. So, when a patient shows a persistent elevation of the eosinophil count with non-specific myocardial damage, the possibility of this disease, should always be considered. Furthermore, even when an invasive clinical procedure such as endomyocardial biopsy (EMB) is not available or acceptable, corticosteroids should be administered promptly to bring the eosinophil count back to the normal range, thereby halting the progression of disease and reducing patient mortality.

Lys-AuNPs@MoS2 Nanocomposite Self-Assembled Microfluidic Immunoassay Biochip for Ultrasensitive Detection of Multiplex Biomarkers for Cardiovascular Diseases.

The progression of cardiovascular diseases is accompanied by myocardial injury and necrosis, heart failure, and inflammatory response. Accordingly, ultrasensitive and rapid detection of multiple biomarkers plays a vital role in clinical diagnosis and timely treatment. Here, we developed a novel Lys-AuNPs@MoS2 nanocomposite self-assembled microfluidic immunoassay biochip with digital signal output and applied it to the simultaneous detection of multiple serum biomarkers including inflammatory factors and cardiovascular biomarkers, PCT, CRP, IL6, cTnI, cTnT, and NT-BNP, with high throughput and sensitivity. The digital output signal was collected in the solid phase on the chip surface with two-dimensional distribution of targets. Lys-AuNPs@MoS2 nanocomposites self-assembled biochips could simultaneously detect all six biomarkers in 60 samples in 40 min with detection limit of a few to tens of pg/mL for all serum biomarkers. The microfluidic biochip based on Lys-AuNPs@MoS2 nanocomposites provides a promising method in applications for clinical diagnosis.

A Novel Mathematical Model for Correcting the Physiologic Variance of Two-Dimensional Echocardiographic Measurements in Healthy Chinese Adults.

BACKGROUND: To facilitate differentiation between normal and abnormal values, it is necessary to correct echocardiographic measurements for physiologic variance induced by age, gender, and body size variables. METHODS: A total of 34 two-dimensional echocardiographic parameters were measured in 1,224 healthy Chinese adults with body mass index < 25.0 kg/m2. An optimized multivariate allometric model and scaling equations were first developed in 858 subjects (group A), and their reliability was then verified in the remaining 366 subjects (group B). The traditional single-variable isometric model in which parameters are linearly corrected by a single body size variable (height, weight, body mass index, or body surface area) was used for comparison. The success of correction was defined as the absence of significant correlations (r > 0.20, P < .05) between the corrected values and age or any body size variables, while maintaining high correlations (r > 0.80) between the corrected and uncorrected values. RESULTS: Before correction, all 34 parameters correlated significantly with one or more of the physiologic variables of age and body size and differed significantly between men and women on 29 parameters (85.3%) in both groups. The success rate of correction with the single-variable isometric model was only 11.0% (15 of 136 corrections due to four variable corrections used for each parameter), while use of the optimized multivariate allometric model successfully corrected all 34 parameters (100%) for physiologic variance induced by age and body size variables and eliminated the gender differences in 32 parameters (94.1%). A new set of reference values for corrected echocardiographic measurements independent of age, gender, and body size variables were established. CONCLUSIONS: The novel optimized multivariate allometric model developed in this study is superior to traditional the single-variable isometric model in the correction of echocardiographic parameters for physiologic effects of age, gender, and body size variables and thus should be encouraged in both scientific research and clinical practice.

Effects of radiofrequency catheter ablation on left ventricular structure and function in patients with atrial fibrillation: a meta-analysis.

INTRODUCTION: Radiofrequency catheter ablation (RFCA) is an effective therapy for atrial fibrillation (AF). This study was designed to investigate the effects of RFCA on left ventricular (LV) structure and function in AF patients. METHODS AND RESULTS: A systematic literature search in MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials was performed to identify trials involving changes of LV structure and function in AF patients undergoing RFCA. Effect size was expressed as weighted mean difference (WMD) with 95% confidence interval (CI). LV end-diastolic diameter (LVEDD), LV end-systolic diameter (LVESD), LV end-diastolic volume (LVEDV), LV end-systolic volume (LVESV), and LV ejection fraction (LVEF) were estimated. A total of 21 trials including 1,135 participants were qualified for this meta-analysis. Compared to the baseline values, there were significant decreases in LVEDV (WMD, -6.39 ml; 95%CI, -12.46 to -0.33) and LVESV (WMD, -6.39 ml; 95%CI, -11.35 to -1.42) and a significant improvement in LVEF (WMD, 6.23%; 95%CI, 3.70 to 8.75), but no significant changes were observed in LVEDD (WMD, -0.64 mm; 95%CI, -2.40 to 1.13) and LVESD (WMD, -0.38 mm; 95%CI, -1.32 to 0.56) after RFCA. Subgroup analysis demonstrated that patients with low LVEF (WMD, 11.90%; 95%CI, 9.16 to 14.64) gained more benefits than those with normal LVEF (WMD, 1.56%; 95%CI, 0.38 to 2.74). Besides, patients with chronic AF (WMD, 10.96%; 95%CI, 4.92 to 17.01) improved more than those with paroxysmal AF (WMD, 1.93%; 95%CI, -0.27 to 4.12). CONCLUSIONS: RFCA in AF patients could reverse LV structural remodeling and improve LV systolic function, especially in patients with low LVEF and chronic AF.