39 research outputs found
A Novel Loop-Mediated Isothermal Amplification Assay for Serogroup Identification of \u3cem\u3eNeisseria meningitidis\u3c/em\u3e in Cerebrospinal Fluid
We have developed a novel Neisseria meningitidis serogroup-specific loop-mediated isothermal amplification (LAMP) assay for six of the most common meningococcal serogroups (A, B, C, W, X, and Y). The assay was evaluated using a set of 31 meningococcal LAMP assay positive cerebrospinal fluid (CSF) specimens from 1574 children with suspected meningitis identified in prospective surveillance between 1998 and 2002 in Vietnam, China, and Korea. Primer specificity was validated using 15 N. meningitidis strains (including serogroups A, B, C, E, W, X, Y, and Z) and 19 non-N. meningitidis species. The N. meningitidis serogroup LAMP detected down to ten copies and 100 colony-forming units per reaction. Twenty-nine CSF had N. meningitidis serogroup identified by LAMP compared with two CSF in which N. meningitidis serogroup was identified by culture and multi-locus sequence typing. This is the first report of a serogroup-specific identification assay for N. meningitidis using the LAMP method. Our results suggest that this assay will be a rapid, sensitive, and uniquely serogroup-specific assay with potential for application in clinical laboratories and public health surveillance systems
Clinical Evaluation of Loop-Mediated Isothermal Amplification (LAMP) Assay for Rapid Detection of \u3cem\u3eNeisseria meningitidis\u3c/em\u3e in Cerebrospinal Fluid
Background
Neisseria meningitidis (Nm) is a leading causative agent of bacterial meningitis in humans. Traditionally, meningococcal meningitis has been diagnosed by bacterial culture. However, isolation of bacteria from patients’ cerebrospinal fluid (CSF) is time consuming and sometimes yields negative results. Recently, polymerase chain reaction (PCR)-based diagnostic methods of detecting Nm have been considered the gold standard because of their superior sensitivity and specificity compared with culture. In this study, we developed a loop-mediated isothermal amplification (LAMP) method and evaluated its ability to detect Nm in cerebrospinal fluid (CSF).
Methodology/Principal Findings
We developed a meningococcal LAMP assay (Nm LAMP) that targets the ctrA gene. The primer specificity was validated using 16 strains of N. meningitidis (serogroup A, B, C, D, 29-E, W-135, X, Y, and Z) and 19 non-N. meningitidis species. Within 60 min, the Nm LAMP detected down to ten copies per reaction with sensitivity 1000-fold more than that of conventional PCR. The LAMP assays were evaluated using a set of 1574 randomly selected CSF specimens from children with suspected meningitis collected between 1998 and 2002 in Vietnam, China, and Korea. The LAMP method was shown to be more sensitive than PCR methods for CSF samples (31 CSF samples were positive by LAMP vs. 25 by PCR). The detection rate of the LAMP method was substantially higher than that of the PCR method. In a comparative analysis of the PCR and LAMP assays, the clinical sensitivity, specificity, positive predictive value, and negative predictive value of the LAMP assay were 100%, 99.6%, 80.6%, and 100%, respectively. Conclusions/Significance Compared to PCR, LAMP detected Nm with higher analytical and clinical sensitivity. This sensitive and specific LAMP method offers significant advantages for screening patients on a population basis and for diagnosis in clinical settings
Analysis of Market Potential for Škoda Auto in South Korea
While ŠKODA AUTO, the biggest Czech automobile maker, has achieved strong performance in the Asian markets, especially in China and India with ŠKODA growth strategy, the home ground for ŠKODA AUTO has witnessed that the South Korean car manufacturer, Hyundai, has continuously expanded its market shares in Czech Republic. In this regard, this paper aims to evaluate whether ŠKODA AUTO can win the competition and explore an unseen profit opportunity by serving the South Korean market. The first phase of the research reveals ŠKODA AUTO's internationalization motives and expectation about South Korean market regarding its mission and strategy. Having identified the ŠKODA AUTO motives, the second phase of the research begins to analyze the current situation of ŠKODA AUTO in order to diagnose ŠKODA AUTO internal strengths and weaknesses as well as external opportunities and threats and to clarify ŠKODA AUTO international markets portfolio. The third phase of the research is designed to discover whether South Korea provides ŠKODA AUTO with favorable conditions to enter by examining political, economic, social, technological factors as well as cultural factors and psychic distance. Lastly, the fourth phase of this research deals with industry specific factors in order to assess market attractiveness of the South Korean automobile industry and to analyze the competitor as well as to reveal South Korean consumers' perception about imported cars in terms of barriers and drives to purchase imported cars
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Glycemic Choreoballism
This letter was written in response to the following two Case Reports:Roy U, Das SK, Mukherjee A, et al. Irreversible hemichoreahemiballism in a case of nonketotic hyperglycemia presenting as the initial manifestation of diabetes mellitus. Tremor Other Hyperkinet Mov. 2016; 6. doi: 10.7916/D8QZ2B3FCosentino C, Torres L, Nuñez Y, et al. Hemichorea/hemiballism associated with hyperglycemia: report of twenty cases. Tremor Other Hyperkinet Mov. 2016; 6. doi: 10.7916/D8DN454PThis letter prompted response letters from the authors of the original Case Reports:Cosentino C, Torres L, Nunez Y, et al. Reply #1 to: Glycemic choreoballism. Tremor Other Hyperkinet Mov. 2016; 6. doi: 10.7916/D8KW5GBFRoy U, Das SK, Mukherjee A, et al. Reply #2 to: Glycemic choreoballism. Tremor Other Hyperkinet Mov. 2016; 6. doi: 10.7916/D8G44QM1 </p
Forced entrainment by using light therapy, modafinil and melatonin in a sighted patient with non-24-hour sleep-wake disorder
Effect of Dosing Interval on Compliance of Osteoporosis Patients on Bisphosphonate Therapy: Observational Study Using Nationwide Insurance Claims Data
Only a few studies are available on the effect of the dosing interval of bisphosphonate on drug compliance. We analyzed the data of patients who were newly prescribed bisphosphonate using a national insurance claims database. Drug compliance was assessed by calculating medication possession ratio (MPR) over a minimum of a 1-year follow-up. This analysis included 281,996 new bisphosphonate users with a mean age of 68.9 years (92% women). The patients were divided into daily, weekly, monthly, 3-monthly, and switch groups (who changed the drug to other dosing intervals). The average MPR was the highest in the switch group (66%), and the longer the dosing interval, the higher the compliance (3-monthly, 56% vs. daily, 37%). “Non-compliant” was defined as an MPR under 80%. Various factors which were possibly associated with “non-compliant” MPR were investigated using multiple regression analysis. Multivariate analysis showed that male patients were more likely to be non-compliant with pharmacotherapy than female patients, with as odds ratio of 1.389. Younger patients had a significantly lower likelihood of being non-compliant than older patients for age 60–69 vs. age 80+. Long dosing intervals were recommended to improve compliance and special attention was given to older and male patients
GuardiaNN: Fast and Secure On-Device Inference in TrustZone Using Embedded SRAM and Cryptographic Hardware
As more and more mobile/embedded applications employ Deep Neural Networks (DNNs) involving sensitive user data, mobile/embedded devices must provide a highly secure DNN execution environment to prevent privacy leaks. Aimed at securing DNN data, recent studies execute part of a DNN in a trusted execution environment (e.g., TrustZone) to isolate DNN execution from the other processes; however, as the trusted execution environments for mobile/embedded devices provide limited memory protection, DNN data remain unencrypted in DRAM and become vulnerable to physical attacks. The devices can prevent the physical attacks by keeping DNN data encrypted in DRAM; when DNN data get referenced during DNN execution, they get loaded to the SRAM and get decrypted by a CPU core. Unfortunately, using the SRAM with demand paging greatly increases DNN execution time due to the inefficient use of the SRAM and the high CPU consumption of data encryption/decryption. In this paper, we present GuardiaNN, a fast and secure DNN framework which greatly accelerates DNN execution without sacrificing security guarantees. To accelerate secure DNN execution, GuardiaNN first reduces slow DRAM accesses with direct convolutions and maximizes the reuse of SRAM-stored data with DNN-friendly SRAM management. Then, aimed at dedicating the limited CPU resources to DNN execution, GuardiaNN offloads DNN data encryption/decryption onto secure cryptographic hardware and employs pipelining to overlap DNN execution with the encryption/decryption. For eight DNNs chosen from five representative mobile/embedded application domains, our implementation of GuardiaNN on STM32MP157C-DK2 development board achieves a geomean speedup of 15.3x and a geomean energy efficiency improvement of 15.2x over a baseline secure DNN framework which employs demand-paged SRAM to secure sensitive data.N
(NH4)2V7O16 as a Cathode Material for Rechargeable Calcium-Ion Batteries: Structural Transformation and Co-Intercalation of Ammonium and Calcium Ions
Calcium-ion batteries (CIBs) are viable alternatives to lithium-ion batteries. However, few cathode materials can reversibly intercalate Ca ions in anhydrous electrolytes. Most high-capacity materials contain crystal water, causing unwanted reactions on the anode. Herein, we report a crystal-water-free ammonium vanadate, (NH4)2V7O16, as a CIB host material. Synthesized via a microwave-assisted hydrothermal method, (NH4)2V7O16 exhibits a layered structure with stacked V7O16 layers and interlayer ammonium ions hydrogen-bonded to adjacent oxygen atoms. We demonstrate the reversible electrochemical intercalation of Ca2+ ions into (NH4)2V7O16, achieving a reversible capacity of 89 mA h g-1 and an average discharge voltage of ∼3.21 V vs Ca/Ca2+. Although (NH4)2V7O16 displays poor rate capability and cycling performance, we reveal a unique reaction mechanism. During the initial charge, an irreversible structural change occurs, removing all ammonium ions and inserting a small amount of Ca ions, forming Ca0.37V7O16. This suggests an ion-exchange reaction between calcium and ammonium ions. Subsequent cycles exhibit the reversible coinsertion and coextraction of calcium and ammonium ions. We observe that V7O16 lacks structural stability without interlayer cations. Our findings offer insight into electrochemical reaction processes in crystal-water-free layered materials containing interlayer ammonium ions, highlighting the importance of cointercalation between ammonium and carrier ions for reversible cycling. © 2023 American Chemical Society.FALS
Draft genome sequence of the extremely halophilic Halorubrum sp. SAH-A6 isolated from rock salts of the Danakil depression, Ethiopia
The draft genome sequence of Halorubrum sp. SAH-A6, isolated from commercial rock salts of the Danakil depression, Ethiopia. The genome comprised 3,325,770 bp, with the G + C content of 68.0%. The strain has many genes which are responsible for secondary metabolites biosynthesis, transport and catabolism as compared to other Halorubrum archaea members. Abundant genes responsible for numerous transport systems, solute accumulation, and aromatic/sulfur decomposition were detected. The first genomic analysis encourages further research on comparative genomics, and biotechnological applications. The NCBI accession number for this genome is SAMN04278861 and ID: 4278861 and strain deposited with accession number KCTC 43215