Scientific reports
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The COVID-19 pandemic has resulted in an urgent need for a rapid, point of care diagnostic testing that could be rapidly scaled on a worldwide level. We developed and tested a highly sensitive and robust assay based on reverse transcription loop mediated isothermal amplification (RT-LAMP) that uses readily available reagents and a simple heat block using contrived spike-in and actual clinical samples. ⋯ Our optimized RT-LAMP based testing method is a scalable system that is sufficiently sensitive and robust to test for SARS-CoV-2 directly on clinical nasopharyngeal swab samples in viral transport media in 30 min at the point of care without the need for specialized or proprietary equipment or reagents. This cost-effective and efficient one-step testing method can be readily available for COVID-19 testing world-wide, especially in resource poor settings.
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Traumatic brain injury (TBI) is often accompanied by hemorrhage, and treatment of hemorrhagic shock (HS) after TBI is particularly challenging because the two therapeutic treatment strategies for TBI and HS often conflict. Ischemia/reperfusion injury from HS resuscitation can be exaggerated by TBI-induced loss of autoregulation. In HS resuscitation, the goal is to restore lost blood volume, while in the treatment of TBI the priority is focused on maintenance of adequate cerebral perfusion pressure and avoidance of secondary bleeding. ⋯ Finally, sympathetic nervous system (SNS) modulation was higher for the LR group and lower for the PolyhHb group compared to the blood group after reperfusion. In conclusion, our results suggest that PolyhHb could be an alternative to blood for resuscitation from HS after TBI when blood is not available, assuming additional testing demonstrate similar favorable results. PolyhHb restored hemodynamics and oxygen delivery, without the logistical constraints of refrigerated blood.
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Reverse transcriptase-polymerase chain reaction (RT-PCR) testing is an important tool for diagnosing coronavirus disease 2019 (COVID-19). However, performance concerns have emerged recently, notably regarding sensitivity. We hypothesized that the clinical, biological, and radiological characteristics of patients with a false-negative first RT-PCR test and a final diagnosis of COVID-19 might differ from those of patients with a positive first RT-PCR test. ⋯ By multivariate analysis, two factors were independently associated with a lower risk of a first false-negative test, namely, headache (adjusted OR [aOR], 0.07; 95% confidence interval [95% CI], 0.01-0.49]; P = 0.007) and fatigue/malaise (aOR, 0.16; 95% CI, 0.03-0.81; P = 0.027); two other factors were independently associated with a higher risk of a first false-negative test, namely, platelets > 207·103 mm-3 (aOR, 3.81; 95% CI, 1.10-13.16]; P = 0.034) and C-reactive protein > 79.8 mg·L-1 (aOR, 4.00; 95% CI, 1.21-13.19; P = 0.023). Patients with suspected COVID-19 whose laboratory tests indicating marked inflammation were at higher risk of a first false-negative RT-PCR test. Strategies involving serial RT-PCR testing must be rigorously evaluated.
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The development of alternative isothermal amplification assays including multiple cross displacement amplification (MCDA) may address speed and portability limitations of real-time PCR (rt-PCR) methods for SARS-CoV-2 detection. We developed a novel SARS-CoV-2 MCDA assay and compared its speed and sensitivity to loop-mediated isothermal amplification (LAMP) and rt-PCR. Two MCDA assays targeting SARS-CoV-2 N gene and ORF1ab were designed. ⋯ In conclusion, different nucleic acid amplification methods provide different advantages. MCDA is the fastest nucleic acid amplification method for SARS-CoV-2 while rt-PCR is the most sensitive. These advantages should be considered when determining the most suitable nucleic acid amplification methods for different applications.
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Heart failure is a major cause of death with an increasing population of elderly individuals. Several studies have demonstrated the involvement of soluble alpha-Klotho (sαKl) in various diseases. However, the correlation between sαKl and heart failure remains to be understood. ⋯ Interestingly, sαKl levels increased in male patients with heart failure, but not in female patients. Our data suggest that soluble αKl may be a novel biomarker for the responsiveness against treatment in patients with heart failure with reduced ejection fraction. Our findings may help developing a personalized therapy for different patients with heart failure.