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1.
J Orthop ; 45: 43-47, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37841906

RESUMEN

Purpose: This study examined the differences in the center of pressure movement in a one-leg standing position with bare feet, thin-soled shoes, and thick-soled shoes. Methods: In total, 21 male university students participated in this study. The task involved standing on one leg with the dominant foot for 30 s, and the center of pressure movement was measured using a grab coder (G-620; ANIMA, Tokyo, Japan). Three shoe-wearing states, including bare feet, thin-soled shoes, and thick-soled shoes, with the eyes closed and open in each condition. Statistical analysis was performed, with the significance level set as 5%. Results: In the multiple comparison results, the anteroposterior (AP) locus length, AP locus length per second, and maximum amplitude in the AP direction were significantly larger with thick-soled shoes than with bare feet in the closed eyes state. The locus length per unit area was significantly smaller with the thick-soled shoes than with the barefoot condition. Other items did not differ significantly between the shoe-wearing states. Conclusion: Thick-soled shoes caused a greater center of pressure movement in the AP direction in the static one-leg standing position than did the barefoot state. Our findings suggest that the condition with thick-soled shoes was more unstable in static environments.

2.
iScience ; 26(4): 106563, 2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-37123243

RESUMEN

Bromodomain-containing protein 8 (BRD8) is a subunit of the NuA4/TIP60-histone acetyltransferase complex. Although BRD8 has been considered to act as a co-activator of the complex, its biological role remains to be elucidated. Here, we uncovered that BRD8 accumulates in colorectal cancer cells through the inhibition of ubiquitin-dependent protein degradation by the interaction with MRG domain binding protein. Transcriptome analysis coupled with genome-wide mapping of BRD8-binding sites disclosed that BRD8 transactivates a set of genes independently of TIP60, and that BRD8 regulates the expression of multiple subunits of the pre-replicative complex in concert with the activator protein-1. Depletion of BRD8 induced cell-cycle arrest at the G1 phase and suppressed cell proliferation. We have also shown that the bromodomain of BRD8 is indispensable for not only the interaction with histone H4 or transcriptional regulation but also its own protein stability. These findings highlight the importance of bromodomain as a therapeutic target.

3.
Nat Mater ; 22(5): 591-598, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37012436

RESUMEN

Large spin-orbit torques (SOTs) generated by topological materials and heavy metals interfaced with ferromagnets are promising for next-generation magnetic memory and logic devices. SOTs generated from y spin originating from spin Hall and Edelstein effects can realize field-free magnetization switching only when the magnetization and spin are collinear. Here we circumvent the above limitation by utilizing unconventional spins generated in a MnPd3 thin film grown on an oxidized silicon substrate. We observe conventional SOT due to y spin, and out-of-plane and in-plane anti-damping-like torques originated from z spin and x spin, respectively, in MnPd3/CoFeB heterostructures. Notably, we have demonstrated complete field-free switching of perpendicular cobalt via out-of-plane anti-damping-like SOT. Density functional theory calculations show that the observed unconventional torques are due to the low symmetry of the (114)-oriented MnPd3 films. Altogether our results provide a path toward realization of a practical spin channel in ultrafast magnetic memory and logic devices.

4.
J Am Chem Soc ; 145(5): 3008-3015, 2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36710457

RESUMEN

The diversity and complexity of covalent organic frameworks (COFs) can be largely increased by incorporating multiple types of monomers with different topologies or sizes. However, an increase in the number of monomer types significantly complicates the COF formation process. Accordingly, much remains unclear regarding the viability of monomer combinations for ternary or higher-arity COFs. Herein, we show that, through an extensive examination of 12 two-nodes-one-linker ([2 + 1]) combinations, monomer-set viability is determined primarily by the conformational strain originating from disordered monomer arrangements, rather than other factors such as the difference in COF formation kinetics between monomers. When monomers cannot accommodate the strain associated with the formation of a locally disordered, yet crystalline framework, the corresponding [2 + 1] condensation yields a mixture of different COFs or an amorphous polymer. We also demonstrate that a node-linker pair that does not form a binary COF can be integrated to generate a single-phase framework upon addition of a small amount of the third component. These results will clarify the factors behind the successful formation of multicomponent COFs and refine their design by enabling accurate differentiation between allowed and disallowed monomer combinations.

5.
PLoS One ; 17(12): e0279409, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36574389

RESUMEN

As chimeric antigen receptor (CAR)-T cell therapy has been recently applied in clinics, controlling the fate of blood cells is increasingly important for curing blood disorders. In this study, we aim to construct proliferation-inducing and differentiation-inducing CARs (piCAR and diCAR) with two different antigen specificities and express them simultaneously on the cell surface. Since the two antigens are non-cross-reactive and exclusively activate piCAR or diCAR, sequential induction from cell proliferation to differentiation could be controlled by switching the antigens added in the culture medium. To demonstrate this notion, a murine myeloid progenitor cell line 32Dcl3, which proliferates in an IL-3-dependent manner and differentiates into granulocytes when cultured in the presence of G-CSF, is chosen as a model. To mimic the cell fate control of 32Dcl3 cells, IL-3R-based piCAR and G-CSFR-based diCAR are rationally designed and co-expressed in 32Dcl3 cells to evaluate the proliferation- and differentiation-inducing functions. Consequently, the sequential induction from proliferation to differentiation with switching the cytokine from IL-3 to G-CSF is successfully replaced by switching the antigen from one to another in the CARs-co-expressing cells. Thus, piCAR and diCAR may become a platform technology for sequentially controlling proliferation and differentiation of various cell types that need to be produced in cell and gene therapies.


Asunto(s)
Receptores Quiméricos de Antígenos , Ratones , Animales , Receptores Quiméricos de Antígenos/genética , Interleucina-3/metabolismo , Receptores de Citocinas , Diferenciación Celular , Proliferación Celular , Factor Estimulante de Colonias de Granulocitos/farmacología , Células Progenitoras Mieloides/metabolismo
6.
J Phys Ther Sci ; 33(9): 641-645, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34539067

RESUMEN

[Purpose] This study aimed to clarify the relationship between the distance measurements in the Star Excursion Balance Test and participants' posture and lower limb muscle strength. [Participants and Methods] Nine healthy male college students participated in this study. Star Excursion Balance Test distance was measured in both lower limbs by performing anterior, posterolateral, and posteromedial trials; measuring the maximum reach; and performing three-dimensional motion analysis to determine the posture at maximum reach. Isokinetic muscle strength for knee flexion/extension, hip flexion/extension, and hip adduction/abduction were measured using an isokinetic machine. [Results] The hip extension strength, reach side ankle dorsiflexion angles, stance side knee flexion, reach side knee flexion, and knee flexion strength were selected as significant explanatory variables in the anterior direction. For the posteromedial direction, hip adduction and hip extension strength, reach side hip flexion angle, and stance side hip flexion angle were selected. For the posterolateral direction, reach side knee flexion angle and stance side ankle dorsiflexion, knee flexion strength and reach side hip flexion angle were selected. [Conclusion] The related factors differed between the dominant and non-dominant legs even in the same reach direction.

7.
ACS Synth Biol ; 10(5): 990-999, 2021 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-33909409

RESUMEN

Intervention in protein-protein interactions (PPIs) has tremendous effects in the molecular therapy of many diseases. To fulfill the requirements for targeting intracellular proteins, here we develop SOS-localization-based interaction screening (SOLIS), which elaborately mimics signaling via the Ras-mitogen-activated protein kinase pathway. SOLIS employs two chimeric proteins in which a membrane localization motif (CaaX) is fused at the C-terminus of a protein of interest and the catalytic domain of SOS is fused at the C-terminus of another protein of interest. Interaction between the two proteins of interest induces membrane localization of the SOS chimera and cell proliferation. Thus, the SOLIS system enables enrichment of superior binders based on cell proliferation in an intracellular PPI-dependent manner. This was verified by three major modalities against intracellular PPIs (small molecules, peptide aptamers, and intrabodies). The system worked over a broad range of affinities (KD = 0.32-140 nM). In a screening of a site-directed randomized library, novel intrabody clones were selected on the basis of the potency of cell proliferation. Three other PPI detection methods (NanoBiT, SPR, and pull-down assays) were employed to characterize the SOLIS system, and several intrabody clones were judged as false negatives in these assays. SOLIS signals would be less sensitive to the orientation/conformation of the chimeric proteins, and this feature emerges as the advantage of SOLIS as a mammalian cytosolic PPI detection system with few false negatives.


Asunto(s)
Espacio Intracelular/metabolismo , Células Precursoras de Linfocitos B/metabolismo , Mapas de Interacción de Proteínas , Transducción de Señal/genética , Proteínas Son Of Sevenless/metabolismo , Animales , Anticuerpos/metabolismo , Antígenos/metabolismo , Aptámeros de Péptidos/metabolismo , Línea Celular , Membrana Celular/metabolismo , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Interleucina-3/genética , Interleucina-3/metabolismo , Interleucina-3/farmacología , Ratones , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Terapia Molecular Dirigida/métodos , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacología , Transducción de Señal/efectos de los fármacos , Transducción Genética , Transfección , Proteínas ras/metabolismo
8.
J Phys Ther Sci ; 32(6): 391-394, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32581431

RESUMEN

[Purpose] We examined and clarified the relationship between the maximum squat depth and the range of motion of the ankle, knee, and hip joints, and the knee and hip muscle strength. [Participants and Methods] Nine healthy males participated in this study and performed a deep squat with the upper extremities raised; the movement was analyzed by two-dimensional motion analysis. We measured the ankle dorsiflexion, hip flexion, and knee flexion ranges of motion, as well as the knee extension and hip flexion muscle strengths and analyzed the relationship between the squatting motion, the range of motion, and the muscle strength of each joint. [Results] The right ankle dorsiflexion range of motion was a significant predictor of the ankle dorsiflexion angle on both sides. The right knee flexion range of motion was a significant predictor of the knee flexion angle, and the left knee flexion range of motion was a significant predictor of the trunk anterior tilt angle on both sides. The right ankle dorsiflexion range of motion was a significant predictor of the right hip flexion angle and vice versa. [Conclusion] This study reveals that movement on one side affects contralateral movement, which is important when evaluating the deep squat motion as a functional test.

9.
Nano Lett ; 20(8): 5735-5740, 2020 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-32574061

RESUMEN

A variety of nickel oxide compounds have long been studied for their manifestation of various correlated electron phenomena. Recently, superconductivity was observed in nanoscale infinite layer nickelate thin films of Nd0.8Sr0.2NiO2, epitaxially stabilized on SrTiO3 substrates via topotactic reduction from the perovskite precursor phase. Here, we present the synthesis and properties of PrNiO2 thin films on SrTiO3. Upon doping in Pr0.8Sr0.2NiO2, we observe superconductivity with a transition temperature of 7-12 K and robust critical current density at 2 K of 334 kA/cm2. These findings indicate that superconductivity in the infinite layer nickelates is relatively insensitive to the details of the rare earth 4f configuration. Furthermore, they motivate the exploration of a broader family of compounds based on two-dimensional NiO2 planes, which will enable systematic investigation of the superconducting and normal state properties and their underlying mechanisms.

10.
Anal Sci ; 36(10): 1243-1247, 2020 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-32475895

RESUMEN

For improving quality control in the fermented tea production process and advancing the corresponding food labeling with function claims, a rapid and robust hesperidin analysis method using LC-MS/MS with the sample dilution approach was developed by following internationally accepted criteria of the Association of Official Analytical Chemists (AOAC). The linear correlation coefficient (r2) of the regression line was 0.9997 in the concentration range of 0.025 - 2.5 mg/L. The matrix effect evaluated using regression line slope values was negligible. The recovery rate of 100.7% indicated improved trueness. The performance of the newly developed method in determining the hesperidin content of fermented tea samples did not significantly vary from that of a well-established, conventional method. The HorRat values of intra- and inter-laboratory reproducibility studies were both within the acceptable range, indicating sufficient accuracy of the newly developed method according to the AOAC criteria.


Asunto(s)
Citrus/química , Frutas/química , Hesperidina/análisis , Hojas de la Planta/química , Té/química , Cromatografía Liquida , Citrus/metabolismo , Fermentación , Frutas/metabolismo , Hesperidina/metabolismo , Hojas de la Planta/metabolismo , Espectrometría de Masas en Tándem , Té/metabolismo
11.
Appl Microbiol Biotechnol ; 101(18): 6879-6889, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28756590

RESUMEN

Sulfate (SO42-) is an often-utilized and well-understood inorganic sulfur source in microorganism culture. Recently, another inorganic sulfur source, thiosulfate (S2O32-), was proposed to be more advantageous in microbial growth and biotechnological applications. Although its assimilation pathway is known to depend on O-acetyl-L-serine sulfhydrylase B (CysM in Escherichia coli), its metabolism has not been extensively investigated. Therefore, we aimed to explore another yet-unidentified CysM-independent thiosulfate assimilation pathway in E. coli. ΔcysM cells could accumulate essential L-cysteine from thiosulfate as the sole sulfur source and could grow, albeit slowly, demonstrating that a CysM-independent thiosulfate assimilation pathway is present in E. coli. This pathway is expected to consist of the initial part of the thiosulfate to sulfite (SO32-) conversion, and the latter part might be shared with the final part of the known sulfate assimilation pathway [sulfite → sulfide (S2-) â†’ L-cysteine]. This is because thiosulfate-grown ΔcysM cells could accumulate a level of sulfite and sulfide equivalent to that of wild-type cells. The catalysis of thiosulfate to sulfite is at least partly mediated by thiosulfate sulfurtransferase (GlpE), because its overexpression could enhance cellular thiosulfate sulfurtransferase activity in vitro and complement the slow-growth phenotype of thiosulfate-grown ΔcysM cells in vivo. GlpE is therefore concluded to function in the novel CysM-independent thiosulfate assimilation pathway by catalyzing thiosulfate to sulfite. We applied this insight to L-cysteine overproduction in E. coli and succeeded in enhancing it by GlpE overexpression in media containing glucose or glycerol as the main carbon source, by up to ~1.7-fold (1207 mg/l) or ~1.5-fold (1529 mg/l), respectively.


Asunto(s)
Vías Biosintéticas , Escherichia coli/metabolismo , Tiosulfato Azufretransferasa/metabolismo , Tiosulfatos/metabolismo , Cisteína/metabolismo , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Fermentación , Ingeniería Genética , Glucosa/metabolismo , Glicerol/metabolismo , Serina/metabolismo , Sulfatos/metabolismo , Sulfuros/metabolismo , Sulfitos/metabolismo , Azufre/metabolismo , Tiosulfato Azufretransferasa/genética
12.
Sci Rep ; 6: 20436, 2016 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-26853703

RESUMEN

We show a simple and effective way to improve the vortex irreversibility line up to very high magnetic fields (60T) by increasing the density of second phase BaZrO3 nanoparticles. (Y0.77,Gd0.23)Ba2Cu3Oy films were grown on metal substrates with different concentration of BaZrO3 nanoparticles by the metal organic deposition method. We find that upon increase of the BaZrO3 concentration, the nanoparticle size remains constant but the twin-boundary density increases. Up to the highest nanoparticle concentration (n ~ 1.3 × 10(22)/m(3)), the irreversibility field (Hirr) continues to increase with no sign of saturation up to 60 T, although the vortices vastly outnumber pinning centers. We find extremely high Hirr, namely Hirr = 30 T (H||45°) and 24 T (H||c) at 65 K and 58 T (H||45°) and 45 T (H||c) at 50K. The difference in pinning landscape shifts the vortex solid-liquid transition upwards, increasing the vortex region useful for power applications, while keeping the upper critical field, critical temperature and electronic mass anisotropy unchanged.

13.
Parasitol Int ; 65(2): 121-7, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26519611

RESUMEN

Human African trypanosomiasis (HAT) is a disease caused by Kinetoplastid infection. Serological tests are useful for epidemiological surveillance. The aim of this study was to develop a multiplex serological assay for HAT to assess the diagnostic value of selected HAT antigens for sero-epidemiological surveillance. We cloned loci encoding eight antigens from Trypanosoma brucei gambiense, expressed the genes in bacterial systems, and purified the resulting proteins. Antigens were subjected to Luminex multiplex assays using sera from HAT and VL patients to assess the antigens' immunodiagnostic potential. Among T. b. gambiense antigens, the 64-kDa and 65-kDa invariant surface glycoproteins (ISGs) and flagellar calcium binding protein (FCaBP) had high sensitivity for sera from T. b. gambiense patients, yielding AUC values of 0.871, 0.737 and 0.858 respectively in receiver operating characteristics (ROC) analysis. The ISG64, ISG65, and FCaBP antigens were partially cross-reactive to sera from Trypanosoma brucei rhodesiense patients. The GM6 antigen was cross-reactive to sera from T. b. rhodesiense patients as well as to sera from VL patients. Furthermore, heterogeneous antibody responses to each individual HAT antigen were observed. Testing for multiple HAT antigens in the same panel allowed specific and sensitive detection. Our results demonstrate the utility of applying multiplex assays for development and evaluation of HAT antigens for use in sero-epidemiological surveillance.


Asunto(s)
Anticuerpos Antiprotozoarios/sangre , Antígenos de Protozoos/inmunología , Pruebas Serológicas/métodos , Tripanosomiasis Africana/diagnóstico , Anticuerpos Antiprotozoarios/inmunología , Antígenos de Protozoos/genética , Reacciones Cruzadas , Humanos , Curva ROC , Sensibilidad y Especificidad , Trypanosoma brucei gambiense/genética , Trypanosoma brucei gambiense/inmunología , Trypanosoma brucei rhodesiense/inmunología , Tripanosomiasis Africana/sangre , Tripanosomiasis Africana/inmunología
14.
PLoS Negl Trop Dis ; 9(8): e0004021, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26291988

RESUMEN

BACKGROUND: Both Schistosoma mansoni and Schistosoma haematobium cause schistosomiasis in sub-Saharan Africa. We assessed the diagnostic value of selected Schistosoma antigens for the development of a multiplex serological immunoassay for sero-epidemiological surveillance. METHODOLOGY/PRINCIPAL FINDINGS: Diagnostic ability of recombinant antigens from S. mansoni and S. haematobium was assessed by Luminex multiplex immunoassay using plasma from school children in two areas of Kenya, endemic for different species of schistosomiasis. S. mansoni serine protease inhibitor (SERPIN) and Sm-RP26 showed significantly higher reactivity to patient plasma as compared to the control group. Sm-Filamin, Sm-GAPDH, Sm-GST, Sm-LAP1, Sm-LAP2, Sm-Sm31, Sm-Sm32 and Sm-Tropomyosin did not show difference in reactivity between S. mansoni infected and uninfected pupils. Sm-RP26 was cross-reactive to plasma from S. haematobium patients, whereas Sm-SERPIN was species-specific. Sh-SEPRIN was partially cross-reactive to S. mansoni infected patients. ROC analysis for Sm-RP26, Sm-SERPIN and Sh-SERPIN showed AUC values of 0.833, 0.888 and 0.947, respectively. Using Spearman's rank correlation coefficient analysis, we also found significant positive correlation between the number of excreted eggs and median fluorescence intensity (MFI) from the multiplex immunoassays for Sm-SERPIN (ρ = 0.430, p-value = 0.003) and Sh-SERPIN (ρ = 0.433, p-value = 0.006). CONCLUSIONS/SIGNIFICANCE: Sm-SERPIN is a promising species-specific diagnostic antigen. Sh-SEPRIN was partially cross-reactive to S. mansoni infected patients. SERPINs showed correlation with the number of excreted eggs. These indicate prospects for inclusion of SERPINs in the multiplex serological immunoassay system.


Asunto(s)
Antígenos Helmínticos/sangre , Inmunoensayo/métodos , Schistosoma haematobium/inmunología , Schistosoma mansoni/inmunología , Esquistosomiasis Urinaria/diagnóstico , Esquistosomiasis mansoni/diagnóstico , Inhibidores de Serina Proteinasa/sangre , Serpinas/sangre , Secuencia de Aminoácidos , Animales , Anticuerpos Antihelmínticos/sangre , Anticuerpos Antihelmínticos/inmunología , Antígenos Helmínticos/genética , Antígenos Helmínticos/inmunología , Reacciones Cruzadas , Estudios Transversales , Femenino , Humanos , Kenia , Masculino , Datos de Secuencia Molecular , Schistosoma haematobium/genética , Schistosoma haematobium/aislamiento & purificación , Schistosoma mansoni/genética , Schistosoma mansoni/aislamiento & purificación , Esquistosomiasis Urinaria/sangre , Esquistosomiasis Urinaria/parasitología , Esquistosomiasis mansoni/sangre , Esquistosomiasis mansoni/parasitología , Inhibidores de Serina Proteinasa/genética , Inhibidores de Serina Proteinasa/inmunología , Serpinas/genética , Serpinas/inmunología , Especificidad de la Especie
15.
PLoS Negl Trop Dis ; 8(7): e3040, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25078404

RESUMEN

BACKGROUND: A strategy to combat infectious diseases, including neglected tropical diseases (NTDs), will depend on the development of reliable epidemiological surveillance methods. To establish a simple and practical seroprevalence detection system, we developed a microsphere-based multiplex immunoassay system and evaluated utility using samples obtained in Kenya. METHODS: We developed a microsphere-based immuno-assay system to simultaneously measure the individual levels of plasma antibody (IgG) against 8 antigens derived from 6 pathogens: Entamoeba histolytica (C-IgL), Leishmania donovani (KRP42), Toxoplasma gondii (SAG1), Wuchereria bancrofti (SXP1), HIV (gag, gp120 and gp41), and Vibrio cholerae (cholera toxin). The assay system was validated using appropriate control samples. The assay system was applied for 3411 blood samples collected from the general population randomly selected from two health and demographic surveillance system (HDSS) cohorts in the coastal and western regions of Kenya. The immunoassay values distribution for each antigen was mathematically defined by a finite mixture model, and cut-off values were optimized. FINDINGS: Sensitivities and specificities for each antigen ranged between 71 and 100%. Seroprevalences for each pathogen from the Kwale and Mbita HDSS sites (respectively) were as follows: HIV, 3.0% and 20.1%; L. donovani, 12.6% and 17.3%; E. histolytica, 12.8% and 16.6%; and T. gondii, 30.9% and 28.2%. Seroprevalences of W. bancrofti and V. cholerae showed relatively high figures, especially among children. The results might be affected by immunological cross reactions between W. bancrofti-SXP1 and other parasitic infections; and cholera toxin and the enterotoxigenic E. coli (ETEC), respectively. INTERPRETATION: A microsphere-based multi-serological assay system can provide an opportunity to comprehensively grasp epidemiological features for NTDs. By adding pathogens and antigens of interest, optimized made-to-order high-quality programs can be established to utilize limited resources to effectively control NTDs in Africa.


Asunto(s)
Enfermedades Transmisibles/diagnóstico , Enfermedades Transmisibles/epidemiología , Monitoreo Epidemiológico , Pruebas Serológicas , Adolescente , Adulto , Animales , Anticuerpos Antibacterianos/sangre , Anticuerpos Antihelmínticos/sangre , Anticuerpos Antiprotozoarios/sangre , Niño , Preescolar , Femenino , Anticuerpos Anti-VIH/sangre , Humanos , Lactante , Recién Nacido , Kenia , Masculino , Microesferas , Sensibilidad y Especificidad , Estudios Seroepidemiológicos , Adulto Joven
16.
Rev. Inst. Med. Trop. Säo Paulo ; 55(6): 401-406, Nov-Dec/2013. tab, graf
Artículo en Inglés | LILACS | ID: lil-690351

RESUMEN

SUMMARY The use of a “direct PCR” DNA polymerase enables PCR amplification without any prior DNA purification from blood samples due to the enzyme's resistance to inhibitors present in blood components. Such DNA polymerases are now commercially available. We compared the PCR performance of six direct PCR-type DNA polymerases (KOD FX, Mighty Amp, Hemo KlenTaq, Phusion Blood II, KAPA Blood, and BIOTAQ) in dried blood eluted from a filter paper with TE buffer. GoTaq Flexi was used as a standard DNA polymerase. PCR performance was evaluated by a nested PCR technique for detecting Plasmodium falciparum genomic DNA in the presence of the blood components. Although all six DNA polymerases showed resistance to blood components compared to the standard Taq polymerase, the KOD FX and BIOTAQ DNA polymerases were resistant to inhibitory blood components at concentrations of 40%, and their PCR performance was superior to that of other DNA polymerases. When the reaction mixture contained a mild detergent, only KOD FX DNA polymerase retained the original amount of amplified product. These results indicate that KOD FX DNA polymerase is the most resistant to inhibitory blood components and/or detergents. Thus, KOD FX DNA polymerase could be useful in serological studies to simultaneously detect antibodies and DNA in eluents for antibodies. KOD FX DNA polymerase is thus not limited to use in detecting malaria parasites, but could also be employed to detect other blood-borne pathogens. .


RESUMO O propósito deste estudo foi avaliar 6 polimerases de DNA disponíveis comercialmente que são resistentes aos inibidores do PCR para uma amplificação potencial de DNA de amostras de sangue total. O DNA genômico do parasita humano da malária, Plasmodium falciparum, foi analisado sob condições que incluíram os componentes inibidores do sangue extraído de sangue ressacado em papel de filtro. Nossos resultados sugerem que a polimerase KOD FX DNA é superior a outras polimerases. .


Asunto(s)
Humanos , ADN Protozoario/genética , ADN Polimerasa Dirigida por ADN/genética , Malaria Falciparum/diagnóstico , Plasmodium falciparum/genética , Reacción en Cadena de la Polimerasa/métodos , ADN Protozoario/sangre , ADN Polimerasa Dirigida por ADN/sangre , Juego de Reactivos para Diagnóstico , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
17.
Rev Inst Med Trop Sao Paulo ; 55(6): 401-6, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24213192

RESUMEN

The use of a "direct PCR" DNA polymerase enables PCR amplification without any prior DNA purification from blood samples due to the enzyme's resistance to inhibitors present in blood components. Such DNA polymerases are now commercially available. We compared the PCR performance of six direct PCR-type DNA polymerases (KOD FX, Mighty Amp, Hemo KlenTaq, Phusion Blood II, KAPA Blood, and BIOTAQ) in dried blood eluted from a filter paper with TE buffer. GoTaq Flexi was used as a standard DNA polymerase. PCR performance was evaluated by a nested PCR technique for detecting Plasmodium falciparum genomic DNA in the presence of the blood components. Although all six DNA polymerases showed resistance to blood components compared to the standard Taq polymerase, the KOD FX and BIOTAQ DNA polymerases were resistant to inhibitory blood components at concentrations of 40%, and their PCR performance was superior to that of other DNA polymerases. When the reaction mixture contained a mild detergent, only KOD FX DNA polymerase retained the original amount of amplified product. These results indicate that KOD FX DNA polymerase is the most resistant to inhibitory blood components and/or detergents. Thus, KOD FX DNA polymerase could be useful in serological studies to simultaneously detect antibodies and DNA in eluents for antibodies. KOD FX DNA polymerase is thus not limited to use in detecting malaria parasites, but could also be employed to detect other blood-borne pathogens.


Asunto(s)
ADN Protozoario/genética , ADN Polimerasa Dirigida por ADN/genética , Malaria Falciparum/diagnóstico , Plasmodium falciparum/genética , Reacción en Cadena de la Polimerasa/métodos , ADN Protozoario/sangre , ADN Polimerasa Dirigida por ADN/sangre , Humanos , Juego de Reactivos para Diagnóstico , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
18.
Nat Commun ; 4: 2499, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24051678

RESUMEN

The high upper critical field and low anisotropy of the iron-based superconductor BaFe2As2 make it promising for its use in the construction of superconducting magnets. However, its critical current density in high magnetic fields needs to be improved. Here we demonstrate a simple, one-step and industrially scalable means of achieving just this. We show that introducing controlled amounts of uniformly dispersed BaZrO3 nanoparticles into carrier-doped BaFe2As2 significantly improves its superconducting performance without degrading its structural or superconducting properties. Our BaFe2(As0.66P0.33)2 films also exhibit an increase in both the irreversibility line and critical current density at all magnetic-field orientations. These films exhibit nearly isotropic critical current densities in excess of 1.5 MA cm⁻² at 15 K and 1 T--seven times higher than previously reported for BaFe2As2 films. The vortex-pinning force in these films reaches ~59 GN m⁻³ at 5 K and 3-9 T, substantially higher than that of the conventional Nb3Sn wire.

19.
PLoS One ; 8(2): e55960, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23409096

RESUMEN

Enterohemorrhagic Escherichia coli (EHEC) Sakai strain encodes two homologous type III effectors, EspO1-1 and EspO1-2. These EspO1s have amino acid sequence homology with Shigella OspE, which targets integrin-linked kinase to stabilize formation of focal adhesions (FAs). Like OspE, EspO1-1 was localized to FAs in EHEC-infected cells, but EspO1-2 was localized in the cytoplasm. An EHEC ΔespO1-1ΔespO1-2 double mutant induced cell rounding and FA loss in most of infected cells, but neither the ΔespO1-1 nor ΔespO1-2 single mutant did. These results suggested that EspO1-2 functioned in the cytoplasm by a different mechanism from EspO1-1 and OspE. Since several type III effectors modulate Rho GTPase, which contributes to FA formation, we investigated whether EspO1-2 modulates the function of these type III effectors. We identified a direct interaction between EspO1-2 and EspM2, which acts as a RhoA guanine nucleotide exchange factor. Upon ectopic co-expression, EspO1-2 co-localized with EspM2 in the cytoplasm and suppressed EspM2-mediated stress fiber formation. Consistent with these findings, an ΔespO1-1ΔespO1-2ΔespM2 triple mutant did not induce cell rounding in epithelial cells. These results indicated that EspO1-2 interacted with EspM2 to regulate EspM2-mediated RhoA activity and stabilize FA formation during EHEC infection.


Asunto(s)
Escherichia coli Enterohemorrágica/fisiología , Proteínas de Escherichia coli/metabolismo , Adhesiones Focales/metabolismo , Proteínas de Microfilamentos/metabolismo , Proteína de Unión al GTP rhoA/metabolismo , Actinas/metabolismo , Secuencia de Aminoácidos , Línea Celular , Forma de la Célula , Citoplasma/metabolismo , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Interacciones Huésped-Patógeno , Humanos , Proteínas de Microfilamentos/química , Proteínas de Microfilamentos/genética , Modelos Biológicos , Datos de Secuencia Molecular , Unión Proteica , Estabilidad Proteica , Transporte de Proteínas , Alineación de Secuencia , Transducción de Señal , Fibras de Estrés/metabolismo
20.
J Colloid Interface Sci ; 387(1): 141-5, 2012 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-22981512

RESUMEN

Fluoroalkyl end-capped vinyltrimethoxysilane oligomer [R(F)-(VM)(n)-R(F)] underwent the sol-gel reaction under alkaline conditions in the presence of anatase titanium oxide nanoparticles (an-TiO(2)) in tetrahydrofuran to give the corresponding fluorinated oligomer/anatase titanium oxide nanocomposites [R(F)-(VM-SiO(2))(n)-R(F)/an-TiO(2)]. Crystalline structure of an-TiO(2) in the nanocomposites thus obtained was found to keep completely its structure without phase transformation to rutile even after calcination at 1000°C, although crystalline structure of the original an-TiO(2) nanoparticles underwent a complete phase transformation to the rutile under similar conditions. Interestingly, R(F)-(VM-SiO(2))(n)-R(F)/an-TiO(2) nanocomposites before and after calcination at 1000°C exhibited the similar photocatalytic activity for the decolorization of methylene blue under UV light irradiation.

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