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1.
Philos Trans R Soc Lond B Biol Sci ; 379(1906): 20230228, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-38853557

RESUMEN

Rodents actively learn new motor skills for survival in reaction to changing environments. Despite the classic view of the primary motor cortex (M1) as a simple muscle relay region, it is now known to play a significant role in motor skill acquisition. The secondary motor cortex (M2) is reported to be a crucial region for motor learning as well as for its role in motor execution and planning. Although these two regions are known for the part they play in motor learning, the role of direct connection and synaptic correlates between these two regions remains elusive. Here, we confirm M2 to M1 connectivity with a series of tracing experiments. We also show that the accelerating rotarod task successfully induces motor skill acquisition in mice. For mice that underwent rotarod training, learner mice showed increased synaptic density and spine head size for synapses between activated cell populations of M2 and M1. Non-learner mice did not show these synaptic changes. Collectively, these data suggest the potential importance of synaptic plasticity between activated cell populations as a potential mechanism of motor learning. This article is part of a discussion meeting issue 'Long-term potentiation: 50 years on'.


Asunto(s)
Aprendizaje , Corteza Motora , Destreza Motora , Sinapsis , Animales , Corteza Motora/fisiología , Ratones , Aprendizaje/fisiología , Destreza Motora/fisiología , Sinapsis/fisiología , Plasticidad Neuronal/fisiología , Ratones Endogámicos C57BL , Masculino
2.
Int J Mol Sci ; 25(11)2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38891805

RESUMEN

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.


Asunto(s)
Clonación Molecular , L-Lactato Deshidrogenasa , Malaria , Plasmodium knowlesi , Plasmodium knowlesi/genética , Plasmodium knowlesi/enzimología , L-Lactato Deshidrogenasa/genética , L-Lactato Deshidrogenasa/metabolismo , Clonación Molecular/métodos , Malaria/parasitología , Malaria/diagnóstico , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Animales , Humanos , Expresión Génica , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismo
3.
Microorganisms ; 12(5)2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38792706

RESUMEN

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.

4.
Int J Mol Sci ; 24(13)2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37446261

RESUMEN

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.


Asunto(s)
Malaria Vivax , Malaria , Humanos , Plasmodium vivax/genética , L-Lactato Deshidrogenasa/genética , L-Lactato Deshidrogenasa/química , Escherichia coli/genética , Malaria Vivax/parasitología , Malaria/genética , Codón/genética
5.
Biomedicines ; 11(4)2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-37189638

RESUMEN

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.

6.
RSC Adv ; 12(45): 29535-29542, 2022 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-36320752

RESUMEN

Herein, we report a sensitive and selective enzyme-linked aptamer-based sandwich assay (ELASA) to detect Plasmodium falciparum lactate dehydrogenase (PfLDH), which is an attractive biomarker for malaria diagnosis and antimalarial medication. We performed the sandwich assay with a single aptamer sequence, called 2008s, owing to the structural properties of the PfLDH tetramer instead of using a conventional sandwich assay with two different aptamers (or antibodies) for capturing and probing a target molecule. First, the biotinylated PfLDH aptamer was linked with immobilized streptavidin on a microwell plate for binding flexibility, and then PfLDH was bound to the aptamer. Next, a horseradish peroxidase-conjugated aptamer of the same sequence was used to analyze PfLDH quantitatively. Using this approach, the limit of detection (LOD) of PfLDH with the naked eye was 100 ng mL-1, and the LOD and limit of quantification from the absorbance measurements were 34.9 ng mL-1 and 95.5 ng mL-1, respectively, based on PfLDH spiked blood samples. Our proposed method selectively binds PfLDH, not human lactate dehydrogenase. Therefore, this method may be a valuable tool for diagnosing, monitoring, and quarantining malaria cases easily and rapidly.

7.
Biosensors (Basel) ; 12(9)2022 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-36140125

RESUMEN

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.


Asunto(s)
Técnicas Analíticas Microfluídicas , Microfluídica , Bioensayo/métodos , Fosfatasas de Especificidad Dual , Inhibidores Enzimáticos , Colorantes Fluorescentes , Técnicas Analíticas Microfluídicas/métodos , Microfluídica/métodos
8.
Neuroscience ; 485: 163-170, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35051529

RESUMEN

The primary motor cortex, a dynamic center for overall motion control and decision making, undergoes significant alterations upon neural stimulation. Over the last few decades, data from numerous studies using rodent models have improved our understanding of the morphological and functional plasticity of the primary motor cortex. In particular, spatially specific formation of dendritic spines and their maintenance during distinct behaviors is considered crucial for motor learning. However, whether the modifications of specific synapses are associated with motor learning should be studied further. In this review, we summarized the findings of prior studies on the features and dynamics of the primary motor cortex in rodents.


Asunto(s)
Espinas Dendríticas , Corteza Motora , Animales , Espinas Dendríticas/fisiología , Corteza Motora/fisiología , Plasticidad Neuronal/fisiología , Roedores , Sinapsis/fisiología
9.
BMC Musculoskelet Disord ; 21(1): 800, 2020 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-33267845

RESUMEN

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.


Asunto(s)
Fracturas del Húmero , Fracturas del Hombro , Placas Óseas , Tornillos Óseos , Fijación Interna de Fracturas , Humanos , Fracturas del Hombro/diagnóstico por imagen , Fracturas del Hombro/cirugía , Resultado del Tratamiento
10.
IEEE Trans Vis Comput Graph ; 26(11): 3133-3146, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31199260

RESUMEN

We present an interactive visual analytics system that enables traffic congestion exploration, surveillance, and forecasting based on vehicle detector data. Through domain expert collaboration, we have extracted task requirements, incorporated the Long Short-Term Memory (LSTM) model for congestion forecasting, and designed a weighting method for detecting the causes of congestion and congestion propagation directions. Our visual analytics system is designed to enable users to explore congestion causes, directions, and severity. Congestion conditions of a city are visualized using a Volume-Speed Rivers (VSRivers) visualization that simultaneously presents traffic volumes and speeds. To evaluate our system, we report performance comparison results, wherein our model is more accurate than other forecasting algorithms. We demonstrate the usefulness of our system in the traffic management and congestion broadcasting domains through three case studies and domain expert feedback.

11.
J Craniofac Surg ; 29(5): 1220-1223, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29521744

RESUMEN

BACKGROUND: Nasal septal cartilage and conchal cartilages are preferred sources of grafts in augmentation rhinoplasty. Rib cartilage can also be used, but it may evoke a patient's concerns about a scar and an extensive surgery. In such cases, irradiated homologous costal cartilage (IHCC) can be a useful alternative. However, controversy still exists in many literatures regarding complications with use of IHCC. Therefore, the authors reviewed our experiences with IHCC in rhinoplasty and analyzed the complications in relation to graft location. METHODS: A retrospective chart review was made of all patients who underwent rhinoplasty with IHCC between 2007 and 2015. A total of 323 patients were included. The authors considered the cases that required revision surgery for external aesthetic changes as complications. The authors defined major complications, including resorption, infection, fracture, or warping. RESULTS: The total complication rate was 8%. Two fractures (0.6%), 4 fragmentation (1.2%), 4 resorptions (1.2%), 4 infections (1.2%), and 2 warpings (0.6%) were noted. Most of these complications occurred for the septal extension graft. Other complications, including 1 nasal obstruction, 2 visible contours, 3 caudal septal deviations, and 4 cases of unfavorable results (patient unsatisfactions), were noted. CONCLUSIONS: Based on the outcomes of this study, the authors concluded that IHCC is a useful and reliable source of cartilage graft and can serve as an alternative graft material for rhinoplasty. However, care must be taken in use of IHCC graft in areas under tension such as septal extension graft, though its complication rate is low.


Asunto(s)
Aloinjertos/trasplante , Cartílago Costal/trasplante , Rinoplastia , Humanos , Complicaciones Posoperatorias , Estudios Retrospectivos , Rinoplastia/efectos adversos , Rinoplastia/instrumentación , Rinoplastia/métodos , Rinoplastia/estadística & datos numéricos
12.
Int J Syst Evol Microbiol ; 68(3): 745-750, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29458473

RESUMEN

A novel actinobacterial strain, designated EPI-7T, was isolated on R2A agar from human skin (keratinocytes) and subjected to a taxonomic study using a polyphasic approach. Strain EPI-7T showed a Gram-positive reaction, was non-motile, non-spore-forming, and cells had a rod-shape. Colonies were round, convex and pale yellow. Phylogenetic analysis based on 16S rRNA gene sequences showed that the novel isolate formed a cluster with several uncultured bacterial clones and with cultured members of the genera Modestobacter and Sporichthya. The 16S rRNA gene sequence similarities with respect to the type strains of recognized species from the above genera and other phylogenetic neighbours ranged from 92.6 to 93.4 %. The G+C content of the genomic DNA was 68.9 mol%. The only isoprenoid quinone was MK-9(H4), and the major fatty acids detected were C17 : 1ω8c, C16 : 0, iso-C15 : 0 and summed feature 3. The major polar lipids were found to be phosphatidylethanolamine, phosphatidylinositol, three unidentified phospholipids, phosphatidylglycerol, phosphatidylcholine, two unidentified amino lipids and three unidentified lipids. The cell-wall peptidoglycan contained meso-diaminopimelic acid, glutamic acid and alanine. Whole-cell sugars present included rhamnose, glucose and galactose. The combination of the genotypic and phenotypic data allowed differentiation of strain EPI-7T from its closest phylogenetic neighbours and provided evidence that strain EPI-7T represents a novel genus and species in the family Sporichthyaceae. The name Epidermidibacterium keratini gen. nov., sp. nov. is proposed with the type strain being EPI-7T (=KCCM 90264T=JCM 31644T).


Asunto(s)
Actinomycetales/clasificación , Epidermis/microbiología , Queratinocitos/microbiología , Filogenia , Actinomycetales/genética , Actinomycetales/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Grasos/química , Humanos , Peptidoglicano/química , Fosfolípidos/química , Pigmentación , ARN Ribosómico 16S/genética , República de Corea , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/química
13.
Arch Plast Surg ; 43(4): 316-20, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27462563

RESUMEN

Cosmetic lateral canthoplasty, in which the size of the eye is increased by extending the palpebral fissure and decreasing the degree of the eye slant, has become a prevalent procedure for East Asians. However, it is not uncommon for there to be complications or unfavorable results after the surgery. With this in mind, the authors have designed a surgical method to reduce complications in cosmetic lateral canthoplasty by preserving the lateral canthal angle. We discuss here the anatomy required for surgery, the surgical methods, and methods for reducing complications during cosmetic lateral canthoplasty.

14.
Orthop Surg ; 5(4): 289-92, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24254453

RESUMEN

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.


Asunto(s)
Artroscopía/métodos , Calcinosis/cirugía , Lesiones del Manguito de los Rotadores , Tendinopatía/cirugía , Traumatismos de los Tendones/cirugía , Adulto , Artroscopía/efectos adversos , Calcinosis/diagnóstico , Enfermedad Crónica , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Manguito de los Rotadores/cirugía , Técnicas de Sutura , Tendinopatía/diagnóstico , Traumatismos de los Tendones/diagnóstico
15.
Arch Plast Surg ; 40(5): 616-20, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24086819

RESUMEN

BACKGROUND: Nasal tip support is an essential consideration for rhinoplasty in East Asians. There are many techniques to improve tip projection, and among them, the columellar strut is the most popular technique. However, the conventional design is less supportive for rotating the tip. The amount of harvestable septal cartilage is relatively small in East Asians. For an optimal outcome, we propose an L-shaped design for applying the columellar strut. METHODS: To evaluate the anthropometric outcomes, the change in nasal tip projection and the columella-labial angle were analyzed by comparing preoperative and postoperative photographs. The anthropometric study group consisted of 25 patients who underwent the same operative technique of an L-shaped strut graft using septal cartilage and were followed up for more than 9 months. RESULTS: There were statistically significant differences between the preoperative and postoperative values in the nasal tip projection ratio and columella-labial angle. We did not observe any complications directly related to the L-shaped columellar strut in the anthropometric study group. CONCLUSIONS: The L-shaped columellar strut has advantages not only in the controlling of tip projection and rotation, but in that it needs a smaller amount of cartilage compared to the conventional septal extension graft. It can therefore be an alternative technique for nasal tip plasty when there is an insufficient amount of harvestable septal cartilage.

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