A Low-Cost, Sensitive Reporter System Using Membrane-Tethered Horseradish Peroxidase for Efficient Gene Expression Analysis.

Reporter gene assays are essential for high-throughput analysis, such as drug screening or determining downstream signaling activation/inhibition. However, use of this technology has been hampered by the high cost of the substrate (e.g., d-Luciferin (d-Luc)) in the most common firefly luciferase (FLuc) reporter gene assay. Although alternate luciferase is available worldwide, its substrate has remained expensive, and a more affordable option is still in demand. Here, we present a membrane-tethered horseradish peroxidase (mHRP), a new reporter system composed of a cell membrane expressing HRP that can preserve its enzymatic function on the cell surface, facilitates contact with HRP substrates (e.g., ABTS and TMB), and avoids the cell lysis process and the use of the high-priced luciferase substrate. An evaluation of the light signal sensitivity of mHRP compared to FLuc showed that both had comparable signal sensitivity. We also identified an extended substrate half-life of more than 5-fold that of d-Luc. Of note, this strategy provided a more stable detection signal, and the cell lysis process is not mandatory. Furthermore, with this strategy, we decreased the total amount of time taken for analysis and increased the time of detection limit of the reporter assay. Pricing analysis showed a one-third to one twenty-eighth price drop per single test of reporter assay. Given the convenience and stability of the mHRP reporter system, we believe that our strategy is suitable for use as an alternative to the luciferase reporter assay.

Controlled Encapsulation of Gold Nanoparticles into Zr-Metal-Organic Frameworks with Improved Detection Limitation of Volatile Organic Compounds via Surface-Enhanced Raman Scattering.

Volatile organic compounds (VOCs) have harmful effects on human health and the environment but detecting low levels of VOCs is challenging due to a lack of reliable biomarkers. However, incorporating gold nanoparticles (Au NPs) into metal-organic frameworks (MOFs) shows promise for VOC detection. In this study, we developed nanoscale Au@UiO-66 that exhibited surface-enhanced Raman scattering (SERS) activity even at very low levels of toluene vapors (down to 1.0 ppm) due to the thickness of the shell and strong π-π interactions between benzenyl-type linkers and toluene. The UiO-66 shell also increased the thermal stability of the Au NPs, preventing aggregation up to 550 °C. This development may be useful for sensitive detection of VOCs for environmental protection purposes.

A Data-Driven Model with Feedback Calibration Embedded Blood Pressure Estimator Using Reflective Photoplethysmography.

Ambulatory blood pressure (BP) monitoring (ABPM) is vital for screening cardiovascular activity. The American College of Cardiology/American Heart Association guideline for the prevention, detection, evaluation, and management of BP in adults recommends measuring BP outside the office setting using daytime ABPM. The recommendation to use night-day BP measurements to confirm hypertension is consistent with the recommendation of several other guidelines. In recent studies, ABPM was used to measure BP at regular intervals, and it reduces the effect of the environment on BP. Out-of-office measurements are highly recommended by almost all hypertension organizations. However, traditional ABPM devices based on the oscillometric technique usually interrupt sleep. For all-day ABPM purposes, a photoplethysmography (PPG)-based wrist-type device has been developed as a convenient tool. This optical, noninvasive device estimates BP using morphological characteristics from PPG waveforms. As measurement can be affected by multiple variables, calibration is necessary to ensure that the calculated BP values are accurate. However, few studies focused on adaptive calibration. A novel adaptive calibration model, which is data-driven and embedded in a wearable device, was proposed. The features from a 15 s PPG waveform and personal information were input for estimation of BP values and our data-driven calibration model. The model had a feedback calibration process using the exponential Gaussian process regression method to calibrate BP values and avoid inter- and intra-subject variability, ensuring accuracy in long-term ABPM. The estimation error of BP (ΔBP = actual BP-estimated BP) of systolic BP was -0.1776 ± 4.7361 mmHg; ≤15 mmHg, 99.225%, and of diastolic BP was -0.3846 ± 6.3688 mmHg; ≤15 mmHg, 98.191%. The success rate was improved, and the results corresponded to the Association for the Advancement of Medical Instrumentation standard and British Hypertension Society Grading criteria for medical regulation. Using machine learning with a feedback calibration model could be used to assess ABPM for clinical purposes.

Validation of shock index for predicting mortality in older patients with dengue fever.

BACKGROUND: Older adults have a higher mortality for dengue fever (DF). However, the best method for predicting mortality is still unclear. AIMS: We conducted this study to evaluate the shock index (SI) for this issue. METHODS: A retrospective case-control study was conducted by recruiting older patients (≥ 65 years old) with DF who visited the study hospital in southern Taiwan during the 2015 DF outbreak. Demographic data, vital signs, past histories, decision groups, complications, and mortality were included in the analyses. We evaluated the accuracy of SI ≥ 1 for predicting 30-day mortality in this population. RESULTS: A total of 626 patients with a mean age of 74.1 years and nearly equal sex distribution were recruited. The mean of SI (± standard deviation [SD]) was 0.6 (± 0.2) and patients with a SI ≥ 1 accounted for 3.5% of the total patients. Logistic regression showed that patients with SI ≥ 1 had a higher mortality than those with SI < 1 (odds ratio: 8.49; 95% confidence interval: 1.76-17.92). The area under the receiver-operating characteristic was 0.76, and the Hosmer-Lemeshow goodness of fit test was 0.48. The SI ≥ 1 had a sensitivity, specificity, positive predictive value, and negative predictive value of 14.8%, 97.0%, 18.2%, and 96.2% for predicting mortality. CONCLUSIONS: The SI ≥ 1 is an easy tool that can be potentially used to predict 30-day mortality in older DF patients, especially in DF outbreak. It has a high specificity and negative predictive value for excluding patients with high-risk mortality.

Standing Posture at Work Does Not Increase the Risk of Varicose Veins among Health Care Providers in Taiwan.

OBJECTIVE: This study compared the risk of varicose veins (VV) among physicians, nonphysician health care providers (HCP), and the general population. SUBJECTS AND METHODS: The Taiwan National Health Insurance Research Database was used to identify 28,844 physicians and 26,099 nonphysician HCP and an identical number of age- and sex-matched patients from the general population. Using logistic regression analyses, VV risks between physicians and the general population, nonphysician HCP and the general population, and physicians and nonphysician HCP, and among physician specialists were compared by tracing their medical histories between 2007 and 2011. RESULTS: Physicians and nonphysician HCP had cumulative VV incidences of 0.12% (34/28,844) and 0.13% (33/26,099), respectively, during the 5-year period, compared to that of the general population within the same 5-year period. Physicians and nonphysician HCP did not have a higher VV risk than the general population after adjusting for deep vein thrombosis (DVT) history (adjusted odds ratio [AOR] 0.86; 95% confidence interval [CI] 0.53-1.40, and AOR 1.43; 95% CI 0.82-2.50, respectively). Physicians did not a have higher VV risk than nonphysician HCP (AOR 0.80; 95% CI 0.43-1.51) after adjusting for age, sex, and DVT history. Surgery had the highest incidence (0.22%) while pediatrics and emergency medicine had the lowest incidence (0%) of VV risk among physician specialists; however, the difference was not significant (all p values >0.05). CONCLUSION: In this study, VV risk did not differ among physicians, nonphysician HCP, and the general population.

Exploring Enzyme Encapsulation Efficiency in MOFs Using Eco-friendly Approaches.

The encapsulation of protein enzymes in metal-organic frameworks (MOFs) has been recognized as an effective enzyme immobilization approach. In this study, we demonstrated the influence of enzyme amount and the isoelectric points (pI) of different enzymes on the enzyme loading capacity in both mechanochemical (ball-milling) and water-based approaches. We found that increasing enzyme amounts enhances MOF enzyme loading without compromising activity, while the MOF shell protects encapsulated enzymes from proteinase K degradation through its size-sheltering mechanism. However, an excess of enzymes can hinder the formation of ZIF-90. Moreover, enzymes with low pI values (e.g., catalase, pI 5.4) facilitate encapsulation in MOFs, whereas enzymes with high pI values (e.g., lysozyme, pI 11.35) are more challenging to encapsulate. The simulation results revealed that increasing the enzyme amounts and pI values raises the activation energy necessary for MOF formation. This study highlights the crucial role of enzyme properties in the encapsulation process within MOFs, providing valuable insights for fabricating enzyme-MOF biocomposites for diverse applications, such as protein drug delivery.

Fibrinogen-Like Protein 1 Serves as an Anti-Inflammatory Agent for Collagen-Induced Arthritis Therapy in Mice.

Fibrinogen-like protein 1 (FGL1) was recently identified as a major ligand of lymphocyte-activation gene-3 (LAG-3) on activated T cells and serves as an immune suppressive molecule for regulation of immune homeostasis. However, whether FGL1 has therapeutic potential for use in the T cell-induced the autoimmune disease, rheumatoid arthritis (RA), is still unknown. Here, we attempted to evaluate the effect of FGL1 protein on arthritis progression. We also evaluated potential adverse events in a collagen-induced arthritis (CIA) mouse model. We first confirmed that soluble Fgl1 protein could specifically bind to surface Lag-3 receptor on 3T3-Lag-3 cells and further inhibit interleukin (IL-2) and interferon gamma (IFNγ) secretion from activated primary mouse T cells by 95% and 43%, respectively. Intraperitoneal administration of Fgl1 protein significantly decreased the inflammatory cytokine level (i.e., IL-1ß and IL-6) in local paw tissue, and prevented joint inflammation, cellular infiltration, bone deformation and attenuated collagen-induced arthritis progression in vivo. We further demonstrated that exogenous Fgl1 does not cause obvious adverse events during treatment by monitoring body weight and liver weight, and assessing the morphology of several organs (i.e., heart, liver, spleen, lung and kidney) by pathological studies. We expect that Fgl1 protein may be suitable to serve as a potential therapeutic agent for treatment of RA or even other types of T cell-induced autoimmune or inflammatory diseases in the future.

Cyclopentadithiophene-benzoic acid copolymers as conductive binders for silicon nanoparticles in anode electrodes of lithium ion batteries.

Cyclopentadithiophene and methyl-2,5-dibromobenzoate have been copolymerised via palladium complex catalysed direct arylation. The methyl ester group in the benzoate unit is converted to the carboxyl group via saponification. The polymers are mixed with Si nanoparticles for use as conducting binders in the fabrication of an anode electrode in lithium ion batteries. The battery with the electrode incorporating the saponified polymer shows much higher specific capacity of up to 1820 mA h g-1 (total weight) and a higher stability compared with the battery including the polymer before the saponification.

A cell-based screening identifies compounds from the stem of Momordica charantia that overcome insulin resistance and activate AMP-activated protein kinase.

Treatment of insulin resistance is a critical strategy in the prevention and management of type 2 diabetes. The crude extracts from all parts of Momordica charantia L. have been reported by many studies for the effective treatment of diabetes and related complications. However, the exact ingredients responsible for the hypoglycemic effect and the underlying mechanism of their actions have not been well characterized because of the lack of a proper assay and screening system. A new cell-based, nonradioactive, and nonfluorescent screening method was demonstrated in this study to screen for natural products from the stem of M. charantia, aiming to identify hypoglycemic components that can overcome cellular insulin resistance. The results suggest triterpenoids being potential hypoglycemic components of the plant and the mechanism underlying their action involving AMP-activated protein kinase.