Aerosolized Colistin for the Treatment of Multidrug-resistant Acinetobacter baumannii Pneumonia: Experience in a Tertiary Care Hospital in Northern Taiwan

Background/PurposeVentilator-associated pneumonia (VAP) due to multidrug-resistant (MDR) Acinetobacter baumannii in critically ill patients presents an emerging challenge to clinicians. Administration of aerosolized colistin as an adjunctive therapy is one therapeutic option mentioned in limited evidence-based studies. This study aimed to evaluate the effectiveness of adjunctive aerosolized colistin treatment for VAP due to MDR pathogens.MethodsWe retrospectively reviewed the medical records of patients who had received aerosolized colistin for treatment of VAP due to MDR A. baumannii in our hospital from August to December 2008.ResultsForty-five patients were enrolled in our study. The mean age was 71 ± 15 years. The mean Acute Physiological and Chronic Health Evaluation II (APACHE II) scores on the day of intensive care unit admission and on the first day of aerosolized colistin administration were 22.5 ± 6.7 and 18.9 ± 5.7, respectively. The mean duration of intensive care unit stay was 34 ± 16 days. The mean daily dosage of aerosolized colistin was 4.29 ± 0.82 million IU, and the mean duration of administration was 10.29 days. Seventeen patients (37.8%) had a favorable microbiological outcome and 26 (57.8%) showed a clinical response. Mortality due to all causes was 42.2%. No adverse effects related to inhaled colistin were recorded.ConclusionAerosolized colistin may be considered as an adjunct to intravenous treatments in patients with VAP due to colistin-susceptible MDR A. baumannii in critically ill patients

Clinical characteristics and treatment outcomes of patients with tubo-ovarian abscess at a tertiary care hospital in Northern Taiwan

Background/PurposeControversy exists regarding the need for surgical intervention in patients with tubo-ovarian abscess (TOA). This study was aimed at investigating the clinical characteristics and treatment outcomes in patients with TOA at a tertiary care hospital in Taiwan.MethodsThe medical records of 83 patients who presented at the hospital with TOA between January 1, 2006, and December 31, 2007, were retrospectively reviewed. Outcomes of patients who received medical treatment alone or underwent surgical intervention were analyzed using univariate and logistic regression analyses.ResultsAmong the 83 patients with TOA, 13 patients (15.7%) underwent surgical intervention, and 70 patients (84.3%) received medical treatment alone. Significant variables related to surgical treatment in the univariate analysis were length of stay (short vs. long; t = −2.267, p = 0.026), department of admission (emergency room vs. outpatient department; χ2 = 7.459, p = 0.006), number of live births (nulliparous vs. multiparous; χ2 = 18.202, p = 0.001), and C-reactive protein (CRP) level (high vs. low; t = −2.250, p = 0.028). Logistic regression analysis performed to determine influential factors for surgical treatment showed that the operation odds ratio of three to four live births versus no live births was 33.995 (p = 0.043) and that of two live births versus no live births was 13.598 (p = 0.026).ConclusionPatients with TOA who underwent surgery had a longer duration of hospitalization. Among the patients who underwent surgical intervention, those admitted to the emergency room had higher CRP levels and were more likely to be multiparous

Planning and Implantation of NetFPGA Platform on Network Emulation Testbed

The concepts of cloud computing and Internet applications have expanded gradually and have become more and more important. Researchers need a new, high-speed network to build experimental environments for testing new network protocolswithout affecting existing traffic. In this paper, we describe a way to integrate NetFPGA platform, OpenFlow concept and NetFPGA reference designs into anetwork testbed to improve the packet processing speed and the dynamic adjustability for network emulation experiments. Furthermore, combined with Tunneling and VPLS, the proposed network testbed can be connected to distributed network, thus providing researchers a traffic-controllable and NIC-programmable experimental networking testbed in intra-communicating part

Detecting critical nodes for network vulnerability assessment under cascading failures

Recently, the major challenge in the robustness evaluation of networks is to enhance the detecting the most critical nodes. Many researchers have studied the problem of detecting the list of attacked nodes, which are the number of failed nodes is maximum, in order to protect these nodes. However, there is no any previous works to consider the cost of attacks that the budget is limited is very practical in the real attacks. In this paper, we study the problem of attacking nodes in networks to maximize the total profits of attacked nodes, where the total cost of attacks is remained under the budget. In addition, an algorithm is proposed to solve problem of attacking nodes in the network with limited budget while guaranteeing the high total profits of attacked nodes. Simulation results show that the proposed method provides good performance

LC4SV: A Denoising Framework Learning to Compensate for Unseen Speaker Verification Models

The performance of speaker verification (SV) models may drop dramatically in noisy environments. A speech enhancement (SE) module can be used as a front-end strategy. However, existing SE methods may fail to bring performance improvements to downstream SV systems due to artifacts in the predicted signals of SE models. To compensate for artifacts, we propose a generic denoising framework named LC4SV, which can serve as a pre-processor for various unknown downstream SV models. In LC4SV, we employ a learning-based interpolation agent to automatically generate the appropriate coefficients between the enhanced signal and its noisy input to improve SV performance in noisy environments. Our experimental results demonstrate that LC4SV consistently improves the performance of various unseen SV systems. To the best of our knowledge, this work is the first attempt to develop a learning-based interpolation scheme aiming at improving SV performance in noisy environments

Survival Prediction of Initial Blood pH for Nontraumatic Out-of-hospital Cardiac Arrest Patients in the Emergency Department

SummaryBackgroundMost nontraumatic out-of-hospital cardiac arrest (NTOHCA) patients who fail in prehospital resuscitation receive continued cardiopulmonary resuscitation in the emergency department (ED). Initial blood pH, which can be assessed rapidly in the ED, was examined to see whether it is a strong survival predictor for these patients.MethodsA 1-year retrospective study included consecutive 225 NTOHCA patients at a medical center in northern Taiwan who presented through the emergency medical services system. On arrival at the ED, these patients received continued cardiopulmonary resuscitation, and their initial blood pH data were assessed.ResultsThe pH value was positively correlated with variables such as return of spontaneous circulation, witnessed arrest, short prehospital time (≤20 minutes), and survival. The best cut-off value of initial blood pH, revealed by the receiver operating characteristic curve, was 7.068. The lowest pH value of the survivors was 6.856. The results of logistic regression model analysis shows that the odds ratios of survival was 10.0 (95% confidence interval [CI], 2.1–47.7) for patients with initial blood pH ≥ 7.068, 5.3 (95% CI, 1.48–18.9) for those with nonasystole rhythm, 4.0 (95% CI, 1.1–14.8) for those with prehospital time ≤20 minutes, and 9.1 (95% CI, 2.3–35.2) for those without NaHCO3 administration during resuscitation, respectively.ConclusionA cut-off value of an initial blood pH of 7.068 can serve as a predictor for survival among NTOHCA patients. In addition, patients whose initial blood pH is lower than 6.85 in the ED may not survive until hospital discharge

Drastic population fluctuations explain the rapid extinction of the passenger pigeon

To assess the role of human disturbances in species' extinction requires an understanding of the species population history before human impact. The passenger pigeon was once the most abundant bird in the world, with a population size estimated at 3-5 billion in the 1800s; its abrupt extinction in 1914 raises the question of how such an abundant bird could have been driven to extinction in mere decades. Although human exploitation is often blamed, the role of natural population dynamics in the passenger pigeon's extinction remains unexplored. Applying high-throughput sequencing technologies to obtain sequences from most of the genome, we calculated that the passenger pigeon's effective population size throughout the last million years was persistently about 1/10,000 of the 1800's estimated number of individuals, a ratio 1,000-times lower than typically found. This result suggests that the passenger pigeon was not always super abundant but experienced dramatic population fluctuations, resembling those of an "outbreak" species. Ecological niche models supported inference of drastic changes in the extent of its breeding range over the last glacial-interglacial cycle. An estimate of acorn-based carrying capacity during the past 21,000 y showed great year-to-year variations. Based on our results, we hypothesize that ecological conditions that dramatically reduced population size under natural conditions could have interacted with human exploitation in causing the passenger pigeon's rapid demise. Our study illustrates that even species as abundant as the passenger pigeon can be vulnerable to human threats if they are subject to dramatic population fluctuations, and provides a new perspective on the greatest human-caused extinction in recorded history

Anapole mediated giant photothermal nonlinearity in nanostructured silicon

Featured with a plethora of electric and magnetic Mie resonances, high index dielectric nanostructures offer a versatile platform to concentrate light-matter interactions at the nanoscale. By integrating unique features of far-field scattering control and near-field concentration from radiationless anapole states, here, we demonstrate a giant photothermal nonlinearity in single subwavelength-sized silicon nanodisks. The nanoscale energy concentration and consequent near-field enhancements mediated by the anapole mode yield a reversible nonlinear scattering with a large modulation depth and a broad dynamic range, unveiling a record-high nonlinear index change up to 0.5 at mild incident light intensities on the order of MW/cm2. The observed photothermal nonlinearity showcases three orders of magnitude enhancement compared with that of unstructured bulk silicon, as well as nearly one order of magnitude higher than that through the radiative electric dipolar mode. Such nonlinear scattering can empower distinctive point spread functions in confocal reflectance imaging, offering the potential for far-field localization of nanostructured Si with an accuracy approaching 40 nm. Our findings shed new light on active silicon photonics based on optical anapoles

AMiBA: Broadband Heterodyne CMB Interferometry

The Y. T. Lee Array for Microwave Background (AMiBA) has reported the first science results on the detection of galaxy clusters via the Sunyaev Zel'dovich effect. The science objectives required small reflectors in order to sample large scale structures (20') while interferometry provided modest resolutions (2'). With these constraints, we designed for the best sensitivity by utilizing the maximum possible continuum bandwidth matched to the atmospheric window at 86-102GHz, with dual polarizations. A novel wide-band analog correlator was designed that is easily expandable for more interferometer elements. MMIC technology was used throughout as much as possible in order to miniaturize the components and to enhance mass production. These designs will find application in other upcoming astronomy projects. AMiBA is now in operations since 2006, and we are in the process to expand the array from 7 to 13 elements.Comment: 10 pages, 6 figures, ApJ in press; a version with high resolution figures available at http://www.asiaa.sinica.edu.tw/~keiichi/upfiles/AMiBA7/mtc_highreso.pd

Patchouli Alcohol Modulates the Pregnancy X Receptor/Toll-like Receptor 4/Nuclear Factor Kappa B Axis to Suppress Osteoclastogenesis

The incidence of osteoporosis, which is primarily characterized by plethoric osteoclast (OC) formation and severe bone loss, has increased in recent years. Millions of people worldwide, especially postmenopausal women, suffer from osteoporosis. The drugs commonly used to treat osteoporosis still exist many disadvantages, but natural extracts provide options for the treatment of osteoporosis. Therefore, the identification of cost-effective natural compounds is important. Patchouli alcohol (PA), a natural compound extracted from Pogostemon cablin that exerts anti-inflammatory effects, is used as a treatment for gastroenteritis. However, no research on the use of Patchouli alcohol in osteoporosis has been reported. We found that PA dose-dependently inhibited the receptor activator of nuclear factor kappa-B ligand (RANKL)-induced formation and function of OCs without cytotoxicity. Furthermore, these inhibitory effects were reflected in the significant effect of PA on the NF-κB signaling pathway, as PA suppressed the transcription factors NFATc1 and c-Fos. We also determined that PA activated expression of the nuclear receptor pregnane X receptor (PXR) and promoted the PXR/Toll-like receptor 4 (TLR4) axis to inhibit the nuclear import of NF-κB (p50 and p65). Additionally, PA exerted therapeutic effects against osteoporosis in ovariectomized (OVX) mice, supporting the use of PA as a treatment for osteoporosis in the future