Viral load measurements are an essential tool for the long-term clinical care of human immunodeficiency virus (HIV)-positive individuals. The gold standards in viral load instrumentation, however, are still too limi...Viral load measurements are an essential tool for the long-term clinical care of human immunodeficiency virus (HIV)-positive individuals. The gold standards in viral load instrumentation, however, are still too limited by their size, cost, and sophisticated operation for these measurements to be ubiquitous in remote settings with poor healthcare infrastructure, including parts of the world that are disproportionately affected by HIV infection. The challenge of developing a point-of-care platform capable of making viral load more accessible has been frequently approached but no solution has yet emerged that meets the practical requirements of low cost, portability, and ease-of-use. In this paper, we perform reverse-transcription loop-mediated isothermal amplification (RT-LAMP) on minimally processed HIV-spiked whole blood samples with a microfluidic and silicon microchip platform, and perform fluorescence measurements with a consumer smartphone. Our integrated assay shows amplification from as few as three viruses in a - 60 nL RT- LAMP droplet, corresponding to a whole blood concentration of 670 viruses per μL of whole blood. The technology contains greater power in a digital RT-LAMP approach that could be scaled up for the determination of viral load from a finger prick of blood in the clinical care of HIV-positive individuals. We demonstrate that all aspects of this viral load approach, from a drop of blood to imaging the RT-LAMP reaction, are compatible with lab-on-a-chip components and mobile instrumentation.展开更多
Background A considerable proportion of elderly patients with symptomatic severe heart valve disease are treated conservatively de- spite clear indications for surgical intervention. However, little is known about how...Background A considerable proportion of elderly patients with symptomatic severe heart valve disease are treated conservatively de- spite clear indications for surgical intervention. However, little is known about how advanced age and comorbidities affect treatment deci-sion-making and therapeutic outcomes. Methods Patients (n = 234, mean age: 78.5 ± 3.7 years) with symptomatic severe heart valve dis- ease hospitalized in our center were included. One hundred and fifty-one patients (65%) were treated surgically (surgical group) and 83 (35%) were treated conservatively (conservative group). Factors that affected therapeutic decision-making and treatment outcomes were investi- gated and long-term survival was explored. Results Isolated aortic valve disease, female sex, chronic renal insufficiency, aged _〉 80 years, pneumonia, and emergent status were independent factors associated with therapeutic decision-making. In-hospital mortality for the surgical group was 5.3% (8/151). Three patients (3.6%) in the conservative group died during initial hospitalization. Low cardiac output syndrome and chronic renal insufficiency were identified as predictors of in-hospital mortality in the surgical group. Conservative treatment was identi- fied as the single risk factor for late death in the entire study population. The surgical group had better 5-year (77.2% vs. 45.4%, P 〈 0.0001) and 10-year (34.5% vs. 8.9%, P 〈 0.0001) survival rates than the conservative group, even when adjusted by propensity score-matched analysis. Conclusions Advanced age and geriatric comorbidities profoundly affect treatment decision-making for severe heart valve disease. Valve surgery in the elderly was not only safe but was also associated with good long-term survival while conservative treatment was unfavorable for patients with symptomatic severe valve disease.展开更多
With the rapid development of location-aware devices such as smart phones,Location-Based Services(LBSs) are becoming increasingly popular. Users can enjoy convenience by sending queries to LBS servers and obtaining se...With the rapid development of location-aware devices such as smart phones,Location-Based Services(LBSs) are becoming increasingly popular. Users can enjoy convenience by sending queries to LBS servers and obtaining service information that is nearby.However, these queries may leak the users' locations and interests to the un-trusted LBS servers, leading to serious privacy concerns. In this paper, we propose a Privacy-Preserving Pseudo-Location Updating System(3PLUS) to achieve k-anonymity for mobile users using LBSs. In 3PLUS, without relying on a third party, each user keeps pseudo-locations obtained from both the history locations and the encountered users, and randomly exchanges one of them with others when encounters occur. As a result, each user's buffer is disordered. A user can obtain any k locations from the buffer to achieve k-anonymity locally. The security analysis shows the security properties and our evaluation results indicate that the user's privacy is significantly improved.展开更多
基金supported by funding from the National Institutes of Health (NIH) Exploratory/Developmental Grant (R21) (AI106024)supported by a Ruth L.Kirschstein National Research Service Award for Individual Pred octoral MD/PhD and Other Dual Doctoral Degree Fellows (F30) (AI109825)
文摘Viral load measurements are an essential tool for the long-term clinical care of human immunodeficiency virus (HIV)-positive individuals. The gold standards in viral load instrumentation, however, are still too limited by their size, cost, and sophisticated operation for these measurements to be ubiquitous in remote settings with poor healthcare infrastructure, including parts of the world that are disproportionately affected by HIV infection. The challenge of developing a point-of-care platform capable of making viral load more accessible has been frequently approached but no solution has yet emerged that meets the practical requirements of low cost, portability, and ease-of-use. In this paper, we perform reverse-transcription loop-mediated isothermal amplification (RT-LAMP) on minimally processed HIV-spiked whole blood samples with a microfluidic and silicon microchip platform, and perform fluorescence measurements with a consumer smartphone. Our integrated assay shows amplification from as few as three viruses in a - 60 nL RT- LAMP droplet, corresponding to a whole blood concentration of 670 viruses per μL of whole blood. The technology contains greater power in a digital RT-LAMP approach that could be scaled up for the determination of viral load from a finger prick of blood in the clinical care of HIV-positive individuals. We demonstrate that all aspects of this viral load approach, from a drop of blood to imaging the RT-LAMP reaction, are compatible with lab-on-a-chip components and mobile instrumentation.
文摘Background A considerable proportion of elderly patients with symptomatic severe heart valve disease are treated conservatively de- spite clear indications for surgical intervention. However, little is known about how advanced age and comorbidities affect treatment deci-sion-making and therapeutic outcomes. Methods Patients (n = 234, mean age: 78.5 ± 3.7 years) with symptomatic severe heart valve dis- ease hospitalized in our center were included. One hundred and fifty-one patients (65%) were treated surgically (surgical group) and 83 (35%) were treated conservatively (conservative group). Factors that affected therapeutic decision-making and treatment outcomes were investi- gated and long-term survival was explored. Results Isolated aortic valve disease, female sex, chronic renal insufficiency, aged _〉 80 years, pneumonia, and emergent status were independent factors associated with therapeutic decision-making. In-hospital mortality for the surgical group was 5.3% (8/151). Three patients (3.6%) in the conservative group died during initial hospitalization. Low cardiac output syndrome and chronic renal insufficiency were identified as predictors of in-hospital mortality in the surgical group. Conservative treatment was identi- fied as the single risk factor for late death in the entire study population. The surgical group had better 5-year (77.2% vs. 45.4%, P 〈 0.0001) and 10-year (34.5% vs. 8.9%, P 〈 0.0001) survival rates than the conservative group, even when adjusted by propensity score-matched analysis. Conclusions Advanced age and geriatric comorbidities profoundly affect treatment decision-making for severe heart valve disease. Valve surgery in the elderly was not only safe but was also associated with good long-term survival while conservative treatment was unfavorable for patients with symptomatic severe valve disease.
基金supported by the National Natural Science Foundation of China under Grants No.61003300,No.61272457the Fundamental Research Funds for the Central Universities under Grant No.K5051201041the China 111 Project under Grant No.B08038
文摘With the rapid development of location-aware devices such as smart phones,Location-Based Services(LBSs) are becoming increasingly popular. Users can enjoy convenience by sending queries to LBS servers and obtaining service information that is nearby.However, these queries may leak the users' locations and interests to the un-trusted LBS servers, leading to serious privacy concerns. In this paper, we propose a Privacy-Preserving Pseudo-Location Updating System(3PLUS) to achieve k-anonymity for mobile users using LBSs. In 3PLUS, without relying on a third party, each user keeps pseudo-locations obtained from both the history locations and the encountered users, and randomly exchanges one of them with others when encounters occur. As a result, each user's buffer is disordered. A user can obtain any k locations from the buffer to achieve k-anonymity locally. The security analysis shows the security properties and our evaluation results indicate that the user's privacy is significantly improved.