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Plasmodium knowlesi is the only Plasmodium that causes zoonotic disease among the Plasmodium that cause infection in humans. It is fatal due to its short asexual growth cycle within 24 h. Lactate dehydrogenase (LDH), an enzyme that catalyzes the final step of glycolysis, is a biomarker for diagnosing infection by Plasmodium spp. parasite. Therefore, this study aimed to efficiently produce the soluble form of P. knowlesi LDH (PkLDH) using a bacterial expression system for studying malaria caused by P. knowlesi. Recombinant pET-21a(+)-PkLDH plasmid was constructed by inserting the PkLDH gene into a pET-21a(+) expression vector. Subsequently, the recombinant plasmid was inserted into the protein-expressing Escherichia coli Rosetta(DE3) strain, and the optimal conditions for overexpression of the PkLDH protein were established using this strain. We obtained a yield of 52.0 mg/L PkLDH from the Rosetta(DE3) strain and confirmed an activity of 483.9 U/mg through experiments. This methodology for high-efficiency PkLDH production can be utilized for the development of diagnostic methods and drug candidates for distinguishing malaria caused by P. knowlesi. [ABSTRACT FROM AUTHOR]

Malaria is one of the most prevalent diseases worldwide with high incidence and mortality. Among the five species that can infect humans, Plasmodium ovale morphologically resembles Plasmodium vivax, resulting in misidentification and confusion in diagnosis, and is responsible for malarial disease relapse due to the formation of hypnozoites. P. ovale receives relatively less attention compared to other major parasites, such as P. falciparum and P. vivax, primarily due to its lower pathogenicity, mortality rates, and prevalence rates. To efficiently produce lactate dehydrogenase (LDH), a major target for diagnosing malaria, this study used three Escherichia coli strains, BL21(DE3), BL21(DE3)pLysS, and Rosetta(DE3), commonly used for recombinant protein production. These strains were characterized to select the optimal strain for P. ovale LDH (PoLDH) production. Gene cloning for recombinant PoLDH production and transformation of the three strains for protein expression were performed. The optimal PoLDH overexpression and washing buffer conditions in nickel-based affinity chromatography were established to ensure high-purity PoLDH. The yields of PoLDH expressed by the three strains were as follows: BL21(DE3), 7.6 mg/L; BL21(DE3)pLysS, 7.4 mg/L; and Rosetta(DE3), 9.5 mg/L. These findings are expected to be highly useful for PoLDH-specific diagnosis and development of antimalarial therapeutics. [ABSTRACT FROM AUTHOR]

Electrophysiological recording technologies can provide valuable insights into the functioning of the central and peripheral nervous systems. Surface electrode arrays made of soft materials or implantable multi-electrode arrays with high electrode density have been widely utilized as neural probes. However, neither of these probe types can simultaneously achieve minimal invasiveness and robust neural signal detection. Here, we present an ultra-thin, minimally invasive neural probe (the "NeuroWeb") consisting of hexagonal boron nitride and graphene, which leverages the strengths of both surface electrode array and implantable multi-electrode array. The NeuroWeb open lattice structure with a total thickness of 100 nm demonstrates high flexibility and strong adhesion, establishing a conformal and tight interface with the uneven mouse brain surface. In vivo electrophysiological recordings show that NeuroWeb detects stable single-unit activity of neurons with high signal-to-noise ratios. Furthermore, we investigate neural interactions between the somatosensory cortex and the cerebellum using transparent dual NeuroWebs and optical stimulation, and measure the times of neural signal transmission between the brain regions depending on the pathway. Therefore, NeuroWeb can be expected to pave the way for understanding complex brain networks with optical and electrophysiological mapping of the brain. Minimal invasiveness and robust signal detection are required in neural probes. Here, the authors develop NeuroWeb, an ultra-thin, minimally invasive surface electrode array. In vivo electrophysiological and optogenetic experiments show single-unit activity of neurons with high signal-to-noise ratio. [ABSTRACT FROM AUTHOR]

The demand for ambipolar organic thin-film transistors (OTFTs) is growing daily owing to their direct applications in single-component organic logic circuits, light-emitting transistors, and other types of integrated circuits. Donor–acceptor (DA) organic polymer semiconductors are the best option for developing the semiconducting channel layer in ambipolar OTFTs because they simplify the fabrication of various circuits with low power consumption and high noise margin. Because of its easy solution processability, well-controlled molecular structure, environmental stability, and operational stability, poly naphthalene diimide-thienylene-vinylene-thienylene (PNDI-TVT) is one of the best choices for the DA semiconducting layer of ambipolar OTFTs, which can then be used to develop organic integrated circuits on a single substrate. Due to a considerable mismatch between electron and hole mobility, little investigation has been done on the applications of PNDI-TVT-based ambipolar OTFTs in complementary organic integrated circuits. In this study, we developed high-performance ambipolar OTFTs using PNDI-TVT as a semiconductor and self-assembled monolayer (SAM)-treated gold as the source–drain electrodes, where the SAM treatment was used to achieve a balance between electron and hole mobilities, and thus to improve the performance of the complementary organic inverters fabricated in a single substrate using these ambipolar OTFTs. The SAM-based OTFTs exhibited the improved average electron and hole mobilities of 0.44 cm2 V−1 s−1 (0.21 cm2 V−1 s−1 without SAM) and 0.29 cm2 V−1 s−1 (0.06 cm2 V−1 s−1 without SAM), respectively, while the inverter showed a maximum voltage gain of ∼36 at 50 V which is ∼3 times higher than that without SAM treatment. [ABSTRACT FROM AUTHOR]

Background: Non-alcoholic fatty liver (NAFL) refers to a disease in which fat builds up in the liver, similar to what occurs for those who drink a lot of alcohol, even in cases of not drinking alcohol at all or only in a small amount. Along with non-alcoholic steatohepatitis (NASH), NAFL is a type of non-alcoholic fatty liver disease (NAFLD). Currently, the prevalence of NAFLD is increasing worldwide. A wide range of comorbidities that can increase the risk of NAFLD includes obesity, type 2 diabetes, dyslipidemia, and metabolic syndrome. Objective: This study aimed to discover genetic variants for NAFL in the Korean population. Methods: Differing from previous studies, we conducted a genome-wide association study for NAFL in the selected subjects without comorbidities to rule out bias due to the inclusion of confounding effects of comorbidities. We grouped 424 NAFL cases and 5,402 controls from the Korean Genome and Epidemiology Study (KoGES) subjects without comorbidities such as dyslipidemia, type 2 diabetes, and metabolic syndrome. All subjects including cases and controls did not consume alcohol at all, or consumed less than 20 g/day for men and less than 10 g/day for women. Results: The logistic association analysis adjusting for sex, age, BMI, and waist circumference identified one novel genome-wide significant variant (rs7996045, P = 2.3 × 10−8) for NAFL. This variant was located in the intron of CLDN10 and was not detected using previous conventional approaches in which confounding effects resulting from comorbidities were not considered in the study design stage. In addition, we detected several genetic variants showing suggestive association for NAFL (P < 10−5). Conclusion: The unique strategy in our association analysis of excluding major confounding factors provides, for the first time, an insight into the genuine genetic basis influencing NAFL. [ABSTRACT FROM AUTHOR]

Plasmodium vivax is the most widespread cause of malaria, especially in subtropical and temperate regions such as Asia-Pacific and America. P. vivax lactate dehydrogenase (PvLDH), an essential enzyme in the glycolytic pathway, is required for the development and reproduction of the parasite. Thus, LDH from these parasites has garnered attention as a diagnostic biomarker for malaria and as a potential molecular target for developing antimalarial drugs. In this study, we prepared a transformed Escherichia coli strain for the overexpression of PvLDH without codon optimization. We introduced this recombinant plasmid DNA prepared by insertion of the PvLDH gene in the pET-21a(+) expression vector, into the Rosetta(DE3), an E. coli strain suitable for eukaryotic protein expression. The time, temperature, and inducer concentration for PvLDH expression from this E. coli Rosetta(DE3), containing the original PvLDH gene, were optimized. We obtained PvLDH with a 31.0 mg/L yield and high purity (>95%) from this Rosetta(DE3) strain. The purified protein was characterized structurally and functionally. The PvLDH expressed and purified from transformed bacteria without codon optimization was successfully demonstrated to exhibit its potential tetramer structure and enzyme activity. These findings are expected to provide valuable insights for research on infectious diseases, metabolism, diagnostics, and therapeutics for malaria caused by P. vivax. [ABSTRACT FROM AUTHOR]

Dual drug delivery has become the choice of interest nowadays due to its increased therapeutic efficacy in targeting the tumor site precisely. As quoted in recent literature, it has been known to treat several cancers with an acute course of action. Even so, its use is restricted due to the drug's low pharmacological activity, which leads to poor bioavailability and increases first-pass metabolism. To overcome these issues, a drug delivery system using nanomaterials which would not only encapsulate the drugs of interest but also carry them to the target site of action is needed. Given all these attributes, we have formulated dual drug-loaded nanoliposomes with cisplatin (cis-diamminedichloroplatinum(II) (CDDP)), an effective anti-cancer drug, and diallyl disulfide (DADS), an organosulfur compound derived from garlic. The CDDP and DADS-loaded nanoliposomes (Lipo-CDDP/DADS) exhibited better physical characteristics such as size, zeta potential, polydispersity index, spherical shape, optimal stability, and satisfactory encapsulation percentage. The in vitro anti-cancer activity against MDA-MB-231 and A549 cell lines revealed that Lipo-CDDP/DADS showed significant efficacy against the cancer cell lines, depicted through cell nucleus staining. We conclude that Lipo-CDDP/DADS hold exceptional pharmacological properties with better anti-cancer activity and would serve as a promising formulation to treat various cancers. [ABSTRACT FROM AUTHOR]

This paper aims to discuss the key accomplishments and further prospects of active-matrix (AM) quantum-dot (QD) light-emitting diodes (QLEDs) display. We present an overview and state-of-the-art of QLEDs as a frontplane and non-Si-based thin-film transistors (TFTs) as a backplane to meet the requirements for the next-generation displays, such as flexibility, transparency, low power consumption, fast response, high efficiency, and operational reliability. After a brief introduction, we first review the research on non-Si-based TFTs using metal oxides, transition metal dichalcogenides, and semiconducting carbon nanotubes as the driving unit of display devices. Next, QLED technologies are analyzed in terms of the device structure, device engineering, and QD patterning technique to realize high-performance, full-color AM-QLEDs. Lastly, recent research on the monolithic integration of TFT–QLED is examined, which proposes a new perspective on the integrated device. We anticipate that this review will help the readership understand the fundamentals, current state, and issues on TFTs and QLEDs for future AM-QLED displays. [ABSTRACT FROM AUTHOR]

We report analysis of phosphatase activity and inhibition on droplet-based microfluidic chips. Phosphatases are such attractive potential drug targets because abnormal phosphatase activity has been implicated in a variety of diseases including cancer, neurological disorders, diabetes, osteoporosis, and obesity. So far, several methods for assessing phosphatase activity have been reported. However, they require a large sample volume and additional chemical modifications such as fluorescent dye conjugation and nanomaterial conjugation, and are not cost-effective. In this study, we used an artificial phosphatase substrate 3-O-methylfluorescein phosphate as a fluorescent reporter and dual specificity phosphatase 22. Using these materials, the phosphatase assay was performed from approximately 340.4 picoliter (pL) droplets generated at a frequency of ~40 hertz (Hz) in a droplet-based microfluidic chip. To evaluate the suitability of droplet-based platform for screening phosphatase inhibitors, a dose–response inhibition study was performed with ethyl-3,4-dephostatin and the half-maximal inhibitory concentration (IC50) was calculated as 5.79 ± 1.09 μM. The droplet-based results were compared to microplate-based experiments, which showed agreement. The droplet-based phosphatase assay proposed here is simple, reproducible, and generates enormous data sets within the limited sample and reagent volumes. [ABSTRACT FROM AUTHOR]

Arthroscopic removal, now the main treatment option, has almost replaced open surgery for treatment of resistant calcific tendinitis. In some cases of chronic calcific tendinitis of the shoulder, the calcific materials are hard and adherent to the tendon. Removal of these materials can cause significant intratendinous tears between the superficial and deep layers of the degenerated rotator cuff. Thus far, there are no established surgical techniques for removing the calcific materials while ensuring cuff integrity. Good clinical results for rotator cuff repair were achieved by using an arthroscopic suture bridge technique in patients with long-standing calcific tendinitis. Intact rotator cuff integrity and recovery of signal change on follow-up magnetic resonance imaging scans were confirmed. This is a technical note about a surgical technique and its clinical results with a review of relevant published reports. [ABSTRACT FROM AUTHOR]

Background: Locking plate fixation is one of the treatment strategies for the management of proximal humeral fractures. However, stiffness after locking plate fixation is a clinical concern. The mechanical stiffness of the standard locking plate system may suppress the interfragmentary motion necessary to promote secondary bone healing by callus formation. The far cortical locking (FCL) technique was developed to address this limitation in 2005. FCL increases construct flexibility and promotes callus formation. Our study aimed to evaluate the clinical and radiological outcomes of the FCL technique when implemented in proximal humeral fracture management. Furthermore, we compared the surgical outcomes of FCL with those of the conventional bicortical locking (BCL) screw fixation technique.Methods: Forty-five consecutive patients who had undergone locking fixation for proximal humeral fractures were included in this study. A proximal humeral locking plate (PHILOS) system with BCL screw fixation was used in the first 27 cases, and the periarticular proximal humeral locking plate with FCL screw fixation was used in the final 18 consecutive cases. Functional capacity was assessed using the constant score, American Shoulder and Elbow Surgeons (ASES) score, and range of motion. Radiographic outcomes were evaluated using the Paavolainen method of measuring the neck-shaft angle (NSA).Results: No significant differences in clinical outcomes (ASES score, constant score, and range of motion) were found between the two groups. The union rate at 12 weeks was significantly higher in the FCL group (94.4%) than in the BCL group (66.7%, p = 0.006). No significant differences in NSA were found between the two treatment strategies. The complication rate was not significantly different between the two groups.Conclusions: When implemented in proximal humeral fractures, the FCL technique showed satisfactory clinical and radiological outcomes as compared with the conventional BCL technique. The bone union rate at 12 weeks after surgery was significantly higher in the FCL group than in the BCL group. However, no significant difference in the final bone union rate was found between the two groups. [ABSTRACT FROM AUTHOR]