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1.
Brain ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38875478

RESUMO

USP25 encodes ubiquitin-specific proteases 25, a key member of deubiquitinating enzyme family and is involved in neural fate determination. Although abnormal expression in Down's syndrome was reported previously, the specific role of USP25 in human diseases has not been defined. In this study, we performed trio-based whole exome sequencing in a cohort of 319 cases (families) with generalized epilepsy of unknown etiology. Five heterozygous USP25 variants including two de novo and three co-segregated variants were determined in eight individuals affected by generalized seizures and/or febrile seizures from five unrelated families. The frequency of USP25 variants showed a significantly high aggregation in this cohort compared to the East Asian population and all populations in the gnomAD database. The mean onset ages of febrile and afebrile seizures were 10 months (infancy) and 11.8 years (juvenile), respectively. The patients achieved seizure freedom except one had occasional nocturnal seizures at the last follow-up. Two patients exhibited intellectual disability. Usp25 was ubiquitously expressed in mouse brain with two peaks on embryonic days (E14‒E16) and postnatal day 21, respectively. Similarly, USP25 expressed in fetus/early childhood stage with a second peak at approximately 12‒20 years old in human brain, consistent with the seizure onset age at infancy and juvenile in the patients. To investigate the functional impact of USP25 deficiency in vivo, we established Usp25 knock-out mice, which showed increased seizure susceptibility compared to wild-type mice in pentylenetetrazol-induced seizure test. To explore the impact of USP25 variants, we employed multiple functional detections. In HEK293T cells, the severe phenotype associated variant (p.Gln889Ter) led to a significant reduction of mRNA and protein expressions but formed a stable truncated dimers with increment of deubiquitinating enzyme activities and abnormal cellular aggregations, indicating a gain-of-function effect. The p.Gln889Ter and p.Leu1045del increased neuronal excitability in mice brain, with a higher firing ability in p.Gln889Ter. These functional impairments align with the severity of the observed phenotypes, suggesting a genotype-phenotype correlation. Hence, a moderate association between USP25 and epilepsy was noted, indicating USP25 is potentially a predisposing gene for epilepsy. Our results from Usp25 null mice and the patient-derived variants indicated that USP25 would play epileptogenic role via loss-of-function or gain-of-function effects. The truncated variant p.Gln889Ter would have profoundly different effect on epilepsy. Together, our results underscore the significance of USP25 heterozygous variants in epilepsy, thereby highlighting the critical role of USP25 in the brain.

2.
Anal Chem ; 96(18): 7179-7186, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38661266

RESUMO

This study uses real-time monitoring, at microsecond time scales, with a charge-sensing particle detector to investigate the evaporation and fission processes of methanol/micrometer-sized polystyrene beads (PS beads) droplets and bacterial particles droplets generated via electrospray ionization (ESI) under elevated temperatures. By incrementally raising capillary temperatures, the solvent, such as methanol on 0.75 µm PS beads, experiences partial evaporation. Further temperature increase induces fission, and methanol molecules continue to evaporate until PS ions are detected after this range. Similar partial evaporation is observed on 3 µm PS beads. However, the shorter period of the fission temperature range is necessary compared to 0.75 µm PS beads. For the spherical-shaped bacterium, Staphylococcus aureus, the desolvation process shows a similar fission period as compared to 0.75 µm PS beads. Comparably, the rod-shaped bacteria, Escherichia coli EC11303, and E. coli strain W have shorter fission periods than S. aureus. This research provides insights into the evaporation and fission mechanisms of ESI droplets containing different sizes and shapes of micrometer-sized particles, contributing to a better understanding of gaseous macroion formation.


Assuntos
Escherichia coli , Poliestirenos , Espectrometria de Massas por Ionização por Electrospray , Staphylococcus aureus , Poliestirenos/química , Escherichia coli/química , Tamanho da Partícula , Temperatura , Volatilização , Metanol/química , Microesferas
3.
Exp Physiol ; 109(7): 1188-1198, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38774964

RESUMO

Previous studies have shown that podocyte injury is involved in the development of proteinuria in rats under hypobaric hypoxia conditions. Prolyl hydroxylase inhibitors (PHIs) may reduce proteinuria. This study aimed to further investigate whether the protective effects of hypoxia-inducible factor 1α (HIF1α) on podocyte injury induced by hypobaric hypoxia are related to Krüppel-like factor 4 (KLF4). Rats were housed in a low-pressure oxygen chamber to simulate a high-altitude environment (5000 m), and a PHI was intraperitoneally injected. Urinary protein electrophoresis was performed and the morphology of the podocytes was observed by electron microscopy. Rat podocytes were cultured under 1% O2, and siRNA was used to interfere with KLF4 expression. The protein expression levels of HIF1α, KLF4, CD2-associated protein (CD2AP) and nephrin were determined by western blotting. Compared with those in the experimental group, the rats in the intervention group on day 14 had lower urinary protein levels, increased protein expression levels of CD2AP and nephrin, and reduced podocyte injury. The results of in vitro experiments showed that the protein expression levels of KLF4, CD2AP and nephrin were greater in the PHI intervention group and lower in the HIF1α inhibitors group than in the low-oxygen group. The protein expression of CD2AP and nephrin in the siKLF4-transfected podocytes treated with PHI and HIF1α inhibitors did not differ significantly from that in the low-oxygen group. HIF1α may be involved in reducing progressive high-altitude proteinuria by regulating KLF4 expression and contributing to the repair of podocyte injury induced by hypobaric hypoxia.


Assuntos
Altitude , Subunidade alfa do Fator 1 Induzível por Hipóxia , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like , Podócitos , Ratos Sprague-Dawley , Regulação para Cima , Animais , Podócitos/metabolismo , Podócitos/patologia , Fator 4 Semelhante a Kruppel/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Masculino , Ratos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Proteinúria/metabolismo , Proteínas de Membrana/metabolismo , Proteínas do Citoesqueleto/metabolismo , Proteínas do Citoesqueleto/genética , Hipóxia/metabolismo , Proteínas Adaptadoras de Transdução de Sinal
4.
Appl Microbiol Biotechnol ; 108(1): 350, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38809284

RESUMO

The African swine fever virus (ASFV) has the ability to infect pigs and cause a highly contagious acute fever that can result in a mortality rate as high as 100%. Due to the viral epidemic, the pig industry worldwide has suffered significant financial setbacks. The absence of a proven vaccine for ASFV necessitates the development of a sensitive and reliable serological diagnostic method, enabling laboratories to effectively and expeditiously detect ASFV infection. In this study, four strains of monoclonal antibodies (mAbs) against p72, namely, 5A1, 4C4, 8A9, and 5E10, were generated through recombinant expression of p72, the main capsid protein of ASFV, and immunized mice with it. Epitope localization was performed by truncated overlapping polypeptides. The results indicate that 5A1 and 4C4 recognized the amino acid 20-39 aa, 8A9 and 5E10 are recognized at 263-282 aa, which is consistent with the reported 265-280 aa epitopes. Conserved analysis revealed 20-39 aa is a high conservation of the epitopes in the ASFV genotypes. Moreover, a blocking ELISA assay for detection ASFV antibody based on 4C4 monoclonal antibody was developed and assessed. The receiver-operating characteristic (ROC) was performed to identify the best threshold value using 87 negative and 67 positive samples. The established test exhibited an area under the curve (AUC) of 0.9997, with a 95% confidence interval ranging from 99.87 to 100%. Furthermore, the test achieved a diagnostic sensitivity of 100% (with a 95% confidence interval of 95.72 to 100%) and a specificity of 98.51% (with a 95% confidence interval of 92.02 to 99.92%) when the threshold was set at 41.97%. The inter- and intra-batch coefficient of variation were below 10%, demonstrating the exceptional repeatability of the method. This method can detect the positive standard serum at a dilution as high as 1:512. Subsequently, an exceptional blocking ELISA assay was established with high diagnostic sensitivity and specificity, providing a novel tool for detecting ASFV antibodies. KEY POINTS: • Four strains of ASFV monoclonal antibodies against p72 were prepared and their epitopes were identified. • Blocking ELISA method was established based on monoclonal antibody 4C4 with an identified conservative epitope. • The established blocking ELISA method has a good effect on the detection of ASFV antibody.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Anticorpos Monoclonais , Anticorpos Antivirais , Proteínas do Capsídeo , Ensaio de Imunoadsorção Enzimática , Mapeamento de Epitopos , Animais , Anticorpos Monoclonais/imunologia , Vírus da Febre Suína Africana/imunologia , Vírus da Febre Suína Africana/genética , Ensaio de Imunoadsorção Enzimática/métodos , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Suínos , Febre Suína Africana/diagnóstico , Febre Suína Africana/imunologia , Febre Suína Africana/virologia , Camundongos , Proteínas do Capsídeo/imunologia , Proteínas do Capsídeo/genética , Camundongos Endogâmicos BALB C , Sensibilidade e Especificidade , Epitopos/imunologia
5.
Nano Lett ; 23(21): 9811-9816, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37708490

RESUMO

Extreme ultraviolet (EUV) radiation with wavelengths of 10-121 nm has drawn considerable attention recently for its use in photolithography to fabricate nanoelectronic chips. This study demonstrates, for the first time, fluorescent nanodiamonds (FNDs) with nitrogen-vacancy (NV) centers as scintillators to image and characterize EUV radiations. The FNDs employed are ∼100 nm in size; they form a uniform and stable thin film on an indium-tin-oxide-coated slide by electrospray deposition. The film is nonhygroscopic and photostable and can emit bright red fluorescence from NV0 centers when excited by EUV light. An FND-based imaging device has been developed and applied for beam diagnostics of 50 nm and 13.5 nm synchrotron radiations, achieving a spatial resolution of 30 µm using a film of ∼1 µm thickness. The noise equivalent power density is 29 µW/(cm2 Hz1/2) for the 13.5 nm radiation. The method is generally applicable to imaging EUV radiation from different sources.

6.
Compr Rev Food Sci Food Saf ; 23(2): e13327, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38517017

RESUMO

Food sensory evaluation mainly includes explicit and implicit measurement methods. Implicit measures of consumer perception are gaining significant attention in food sensory and consumer science as they provide effective, subconscious, objective analysis. A wide range of advanced technologies are now available for analyzing physiological and psychological responses, including facial analysis technology, neuroimaging technology, autonomic nervous system technology, and behavioral pattern measurement. However, researchers in the food field often lack systematic knowledge of these multidisciplinary technologies and struggle with interpreting their results. In order to bridge this gap, this review systematically describes the principles and highlights the applications in food sensory and consumer science of facial analysis technologies such as eye tracking, facial electromyography, and automatic facial expression analysis, as well as neuroimaging technologies like electroencephalography, magnetoencephalography, functional magnetic resonance imaging, and functional near-infrared spectroscopy. Furthermore, we critically compare and discuss these advanced implicit techniques in the context of food sensory research and then accordingly propose prospects. Ultimately, we conclude that implicit measures should be complemented by traditional explicit measures to capture responses beyond preference. Facial analysis technologies offer a more objective reflection of sensory perception and attitudes toward food, whereas neuroimaging techniques provide valuable insight into the implicit physiological responses during food consumption. To enhance the interpretability and generalizability of implicit measurement results, further sensory studies are needed. Looking ahead, the combination of different methodological techniques in real-life situations holds promise for consumer sensory science in the field of food research.


Assuntos
Preferências Alimentares , Alimentos , Preferências Alimentares/fisiologia , Preferências Alimentares/psicologia , Comportamento do Consumidor , Percepção
7.
Anal Chem ; 95(32): 12080-12088, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37534668

RESUMO

Nanodiamonds (NDs) are carbon nanoparticles with a large refractive index, a high density, and exceptional chemical stability. When excited by green light, they can emit bright red fluorescence from implanted nitrogen-vacancy (NV) centers. Taking advantage of these properties, we have developed antibody-conjugated NDs as in vitro diagnostic sensors for two complementary assays: particle-enhanced turbidimetric immunoassay (PETIA) and spin-enhanced lateral flow immunoassay (SELFIA). To achieve this goal, monocrystalline diamond powders (∼100 nm in diameter) with or without NV implantation were first treated in molten KNO3 to reduce their size and shape inhomogeneity, followed by surface carboxylation in strong oxidative acids and non-covalent conjugation with antibodies in water. PETIA and SELFIA were carried out separately with a microplate reader and a magnetically modulated fluorescence analyzer. Using C-reactive protein (CRP) as the target antigen, we found that anti-CRP-conjugated NDs exhibited high colloidal stability over 1 month at 4 °C in buffer solution. The limits of detection for 3 µL of CRP sample solution were 0.06 µg/mL and 1 ng/mL with variation coefficients of less than 10 and 15% for PETIA and SELFIA, respectively. These two methods together provide a detection range of 1 ng/mL-10 µg/mL, potentially useful for clinical applications. This work represents the first practical use of rounded monocrystalline NDs as in vitro diagnostic reagents.


Assuntos
Técnicas Biossensoriais , Imunoconjugados , Nanodiamantes , Nanodiamantes/química , Imunoensaio , Diamante , Nitrogênio/química , Anticorpos
8.
J Environ Manage ; 343: 118252, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37247544

RESUMO

The study aimed to investigate the PM2.5 variations in different periods of COVID-19 control measures in Northern Taiwan from Quarter 1 (Q1) 2020 to Quarter 2 (Q2) 2021. PM2.5 sources were classified based on long-range transport (LRT) or local pollution (LP) in three study periods: one China lockdown (P1), and two restrictions in Taiwan (P2 and P3). During P1 the average PM2.5 concentrations from LRT (LRT-PM2.5-P1) were higher at Fuguei background station by 27.9% and in the range of 4.9-24.3% at other inland stations compared to before P1. The PM2.5 from LRT/LP mix or pure LP (Mix/LP-PM2.5-P1) was also higher by 14.2-39.9%. This increase was due to higher secondary particle formation represented by the increase in secondary ions (SI) and organic matter in PM2.5-P1 with the largest proportion of 42.17% in PM2.5 from positive matrix factorization (PMF) analysis. A similar increasing trend of Mix/LP-PM2.5 was found in P2 when China was still locked down and Taiwan was under an early control period but the rapidly increasing infected cases were confirmed. The shift of transportation patterns from public to private to avoid virus infection explicated the high correlation of the increasing infected cases with the increasing PM2.5. In contrast, the decreasing trend of LP-PM2.5-P3 was observed in P3 with the PM2.5 biases of ∼45% at all the stations when China was not locked down but Taiwan implemented a semi-lockdown. The contribution of gasoline vehicle sources in PM2.5 was reduced from 20.3% before P3 to 10% in P3 by chemical signatures and source identification using PMF implying the strong impact of strict control measures on vehicle emissions. In summary, PM2.5 concentrations in Northern Taiwan were either increased (P1 and P2) or decreased (P3) during the COVID-19 pandemic depending on control measures, source patterns and meteorological conditions.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Humanos , Poluentes Atmosféricos/análise , Taiwan/epidemiologia , Material Particulado/análise , COVID-19/epidemiologia , Pandemias , Controle de Doenças Transmissíveis , Poluição do Ar/análise , Emissões de Veículos/análise , Monitoramento Ambiental
9.
Anal Chem ; 94(51): 17819-17826, 2022 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-36512513

RESUMO

Dengue fever is a global mosquito-borne viral infectious disease that has, in recent years, rapidly spread to almost all regions of the world. Lack of vaccination and directed treatment makes detection at the infection's early stages extremely important for disease prevention and clinical care. In this paper, we developed a rapid and highly sensitive dengue detection tool using a novel platform of diagnosis, called spin-enhanced lateral flow immunoassay (SELFIA) with a fluorescent nanodiamond (FND) as a reporter. Taking advantage of the unique magneto-optical properties of negatively charged nitrogen-vacancy centers in the FND, the SELFIA platform utilizes alternating electromagnetic fields to modulate signals from FND's fluorescence to provide sensitive and specific results. With sandwich SELFIA, we could efficiently detect all four dengue non-structural protein (NS1) serotypes (DV1, DV2, DV3, and DV4). The lowest detection concentration of the dengue NS1 antigens varied from 0.1 to 1.3 ng/mL, which is among the lowest limits of detection to date. The FND-based SELFIA technique is up to 500 and 5000 times more sensitive than carbon black and conventional gold nanoparticles, respectively. By using different anti-NS1 antibodies, we could differentiate the NS1 antigen serotypes contained in the tested samples via three simultaneous assays. Proposed SELFIA allows for both qualitative and quantitative differentiation between different NS1 protein serotypes, which will assist in the development of a highly sensitive and specific detection platform for dengue screening that has the potential to detect the disease at its early stages, especially in high-risk and limited-resource areas.


Assuntos
Vírus da Dengue , Dengue , Nanopartículas Metálicas , Animais , Humanos , Sorogrupo , Ouro , Proteínas não Estruturais Virais , Imunoensaio/métodos , Anticorpos Antivirais , Dengue/diagnóstico , Sensibilidade e Especificidade , Ensaio de Imunoadsorção Enzimática/métodos
10.
J Phys Chem A ; 126(21): 3347-3357, 2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35584043

RESUMO

We investigated the formation of small organosilicon molecules─potential precursors to silicon-carbide dust grains ejected by dying carbon-rich asymptotic giant branch stars─in the gas phase via the reaction of atomic carbon (C) in its 3P electronic ground state with silane (SiH4; X1A1) using the crossed molecular beams technique. The reactants collided under single collision conditions at a collision energy of 13.0 ± 0.2 kJ mol-1, leading to the formation of the silylenemethyl radical (HCSiH2; X2B2) via the unimolecular decomposition of triplet silaethylene (H2CSiH2; a3A″). The silaethylene radical was formed via hydrogen migration of the triplet silylmethylene (HCSiH3; X3A″) radical, which in turn was identified as the initial collision complex accessed via the barrierless insertion of atomic carbon into the silicon-hydrogen bond of silane. Our results mark the first observation of the silylenemethyl radical, where previously only its thermodynamically more stable methylsilylidyne (CH3Si; X2A″) and methylenesilyl (CH2SiH; X2A') isomers were observed in low-temperature matrices. Considering the abundance of silane and the availability of atomic carbon in carbon-rich circumstellar environments, our results suggest that future astrochemical models should be updated to include contributions from small saturated organosilicon molecules as potential precursors to pure gaseous silicon-carbides and ultimately to silicon-carbide dust.

11.
Anal Chem ; 93(18): 7140-7147, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33913330

RESUMO

The negatively charged nitrogen-vacancy center in fluorescent nanodiamonds (FNDs) is a point defect with unique magneto-optical properties. It emits far-red fluorescence at ∼700 nm, and its intensity can be magnetically modulated with a depth of more than 10% at a field strength of 30 mT. We have closely examined this property and illustrated its practical use in biomedicine by applying a periodic, time-varying magnetic field to FNDs deposited on a surface or dispersed in a solution with a lock-in detection method. We achieved selective and sensitive detection of 100 nm FNDs on a nitrocellulose membrane at a particle density of 0.04 ng/mm2 (or ∼2 × 104 particles/mm2) and in an aqueous solution with a particle concentration of 1 ng/mL (or ∼1 fM) in 10 s as the detection limits. The utility and versatility of the technique were demonstrated with an application to background-free detection of FNDs as reporters for FND-based lateral flow immunoassays as well as selective quantification of FNDs in tissue digests for in vivo studies.


Assuntos
Nanodiamantes , Fluorescência , Nitrogênio
12.
J Biomed Sci ; 28(1): 28, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33849537

RESUMO

Mesenchymal stem/stromal cells (MSCs) are a promising resource for cell-based therapy because of their high immunomodulation ability, tropism towards inflamed and injured tissues, and their easy access and isolation. Currently, there are more than 1200 registered MSC clinical trials globally. However, a lack of standardized methods to characterize cell safety, efficacy, and biodistribution dramatically hinders the progress of MSC utility in clinical practice. In this review, we summarize the current state of MSC-based cell therapy, focusing on the systemic safety and biodistribution of MSCs. MSC-associated risks of tumor initiation and promotion and the underlying mechanisms of these risks are discussed. In addition, MSC biodistribution methodology and the pharmacokinetics and pharmacodynamics of cell therapies are addressed. Better understanding of the systemic safety and biodistribution of MSCs will facilitate future clinical applications of precision medicine using stem cells.


Assuntos
Transplante de Células-Tronco Mesenquimais/estatística & dados numéricos , Células-Tronco Mesenquimais/fisiologia , Humanos
13.
FASEB J ; 33(11): 12036-12046, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31365830

RESUMO

Uremic pruritus with elevated levels of calcium phosphate (CaP) in skin is a common symptom in patients with chronic kidney disease (CKD). In this study, we demonstrate that intradermal injection of CaP into mice triggered scratching by up-regulating the IL-6 in skin and phosphorylation of ERKs in dorsal root ganglion (DRG) in a dose-dependent manner. IL-6 is essential because the CaP-induced up-regulation of phosphorylated (p)-ERK in DRG was considerably reduced in the IL-6 knockout mice. Microarray analysis in conjunction with real-time PCR revealed a higher mRNA expression of Bruton's tyrosine kinase (BTK) gene in DRG after CaP injection. The inhibition of BTK by ibrutinib noticeably diminish the CaP-induced up-regulation of IL-6 and p-ERK in mice. A high amount of IL-6 was detected in itchy skin and blood of patients with CKD. The expressions of p-BTK and p-ERK in DRG primary cells reached maximum levels at 1 and 10 min, respectively, after treatment of recombinant IL-6 and were significantly reduced by treatment of IL-6 along with ibrutinib. The mechanism by which the CaP-induced pruritus mediated by the IL-6/p-BTK/p-ERK signaling was revealed.-Keshari, S., Sipayung, A. D., Hsieh, C.-C., Su, L.-J., Chiang, Y.-R., Chang, H.-C., Yang, W.-C., Chuang, T.-H., Chen, C.-L., Huang, C.-M. IL-6/p-BTK/p-ERK signaling mediates calcium phosphate-induced pruritus.


Assuntos
Tirosina Quinase da Agamaglobulinemia/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Gânglios Espinais/metabolismo , Interleucina-6/metabolismo , Prurido/metabolismo , Adenina/análogos & derivados , Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Tirosina Quinase da Agamaglobulinemia/genética , Animais , Fosfatos de Cálcio , MAP Quinases Reguladas por Sinal Extracelular/genética , Feminino , Gânglios Espinais/efeitos dos fármacos , Perfilação da Expressão Gênica/métodos , Interleucina-6/genética , Interleucina-6/farmacologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosforilação/efeitos dos fármacos , Piperidinas , Prurido/induzido quimicamente , Prurido/genética , Pirazóis/farmacologia , Pirimidinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Pele/efeitos dos fármacos , Pele/metabolismo , Pele/patologia
14.
Nano Lett ; 19(8): 5697-5702, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31348663

RESUMO

Two-dimensional superconductors have attracted growing interest because of their scientific novelty, structural tunability, and useful properties. Studies of their magnetic responses, however, are often hampered by difficulties to grow large-size samples of high quality and uniformity. We report here an imaging method that employed NV- centers in diamond as a sensor capable of mapping out the microwave magnetic field distribution on an ultrathin superconducting film of micron size. Measurements on a 33 nm thick film and a 125 nm thick bulklike film of Bi2Sr2CaCu2O8+δ revealed that the alternating current (ac) Meissner effect (or repulsion of ac magnetic field) set in at 78 and 91 K, respectively; the latter was the superconducting transition temperature of both films. The unusual ac magnetic response of the thin film presumably was due to thermally excited vortex-antivortex diffusive motion in the film. Spatial resolution of our ac magnetometer was limited by optical diffraction and the noise level was at 14 µT/Hz1/2. The technique could be extended with better detection sensitivity to extract local ac conductivity/susceptibility of ultrathin or monolayer superconducting samples as well as ac magnetic responses of other two-dimensional exotic thin films of limited lateral size.

15.
Am J Physiol Renal Physiol ; 316(6): F1094-F1102, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30892932

RESUMO

The incidence of urothelial carcinoma (UC) is higher in patients undergoing chronic dialysis than in the general population. This study investigated plasma miRNA profiling as the ancillary diagnosis biomarker associated with UC in patients undergoing chronic hemodialysis. We successfully screened out and detected miRNA expression from plasma in eight patients undergoing dialysis through quantitative real-time PCR array analysis and identified eight candidate miRNAs. The candidate miRNAs were then validated using single quantitative RT-PCR assays from 52 plasma samples. The miRNA classifier for ancillary UC detection was developed by multiple logistic regression analyses. Moreover, we validated the classifier by testing another nine samples. Expression levels of miR-150-5p, miR-150-5p/miR-155-5p, miR-378a-3p/miR-150-5p, miR-636/miR-150-5p, miR-150-5p/miR-210-3p, and miR-19b-1-5p/miR-378a-3p were shown to be significantly different between UC and non-UC samples (P = 0.035, 0.0048, 0.016, 0.024, 0.038, and 0.048). Kaplan-Meier curve analysis also showed that low miR-19b-1-5p expression was associated with a worse prognosis (P = 0.0382). We also developed a miRNA classifier based on five miRNA expression levels to predict UC and found that the area under curve was 0.882. The classifier had a sensitivity of 80% (95% confidence interval: 0.5191% to 0.9567%) and a specificity of 83.7% (95% confidence interval: 0.6799% to 0.9381%). This classifier was tested by nine samples with 100% accuracy. The miRNA classifier offers higher sensitivity and specificity than the existing makers. Thus, this approach will improve the prospective diagnosis of UC in patients undergoing chronic hemodialysis.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma/sangue , MicroRNA Circulante/sangue , Detecção Precoce de Câncer/métodos , Perfilação da Expressão Gênica , Diálise Renal/efeitos adversos , Neoplasias Urológicas/sangue , Idoso , Biomarcadores Tumorais/genética , Carcinoma/diagnóstico , Carcinoma/epidemiologia , Carcinoma/genética , MicroRNA Circulante/genética , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Medição de Risco , Fatores de Risco , Taiwan/epidemiologia , Transcriptoma , Neoplasias Urológicas/diagnóstico , Neoplasias Urológicas/epidemiologia , Neoplasias Urológicas/genética , Urotélio/patologia
16.
Bioconjug Chem ; 30(8): 2228-2237, 2019 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-31268690

RESUMO

Delivering functional proteins (such as enzymes) into cells is important in various biological studies and is often accomplished indirectly by transfection with DNA or mRNA encoding recombinant proteins. However, the transfection efficiency of conventional plasmid methods is low for primary cells, which are crucial sources of cell therapy. Here, we present a new platform based on the use of fluorescent nanodiamond (FND) as a biocompatible nanocarrier to enable rapid, effective, and homogeneous labeling of human mesenchymal stem cells (MSCs) with luciferase for multiplex assays and ultrasensitive detection. More than 100 pg of FND and 100 million copies of firefly luciferase can be delivered into each MSC through endocytosis. Moreover, these endocytic luciferase molecules are catalytically active for hours, allowing the cells to be imaged and tracked in vitro as well as in vivo by both fluorescence and bioluminescence imaging. Our results demonstrate that luciferase-conjugated FNDs are useful as multifunctional labels of human stem cells for diverse theranostic applications.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Luciferases/administração & dosagem , Imagem Multimodal/métodos , Nanodiamantes/uso terapêutico , Células-Tronco/metabolismo , Fluorescência , Humanos , Luciferases/metabolismo , Células-Tronco Mesenquimais/metabolismo , Nanomedicina Teranóstica
17.
BMC Public Health ; 19(1): 1352, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31646989

RESUMO

BACKGROUND: Physical activity is related to health-related quality of life, but little evidence from multiple waves of panel data in Asian countries area available. This study aims to explore the impacts of different degree of regular exercise on the trajectories of physical and mental dimensions of health-related quality of life (HRQOL) for community-dwelling Taiwanese adults during 2006-2014. METHODS: Data were derived from the "Landseed Integrated Outreaching Neighborhood Screening (LIONS)" study, with 6182 adults enrolled at the baseline and subsequently followed up to three times till 2014. Linear mixed-effects modeling approach was employed to evaluate the growth curve models of HRQOL (with 16,281 observations) by linear & quadratic time effects, regular exercise (5-level moderate-intensity physical activity), and major influential factors of HRQOL. RESULTS: Regular exercise showed significantly positive dose-response effects on physical HRQOL (ß =1.27~2.54), and regular exercise of 150 min or more showed positive effects on mental HRQOL (ß = 1.55~2.03). Besides, irregular exercise could also improve both physical and mental HRQOL (ß = 1.27 & ß = 0.87). However, such effects were not significant over time (at time slope) on HRQOL. In addition, physical and mental HRQOL improved across time (ß = 1.01 and 1.49, respectively), but the time quadratic effect would significantly offset a little bit on physical dimension (ß = - 0.22). Moreover, being female, increasing age, living alone, or poorer health status were related to lower physical HRQOL; and being younger, living alone, or poorer health status were associated with lower mental HRQOL. CONCLUSIONS: The positive dose-response relationship between regular exercise and HRQOL or its domains was demonstrated for community-dwelling Taiwanese adults. Thus, a regular exercise habit (better ≧150 min per week) is advised for community-based healthcare professionals and the government to incorporate into health promotion strategies and plans.


Assuntos
Exercício Físico , Qualidade de Vida , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Taiwan
18.
J Enzyme Inhib Med Chem ; 34(1): 692-702, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30777474

RESUMO

Matriptase is ectopically expressed in neoplastic B-cells, in which matriptase activity is enhanced by negligible expression of its endogenous inhibitor, hepatocyte growth factor activator inhibitor (HAI)-1. HAI-1, however, is also involved in matriptase synthesis and intracellular trafficking. The lack of HAI-1 indicates that other related inhibitor, such as HAI-2, might be expressed. Here, we show that HAI-2 is commonly co-expressed in matriptase-expressing neoplastic B-cells. The level of active matriptase shed after induction of matriptase zymogen activation in 7 different neoplastic B-cells was next determined and characterised. Our data reveal that active matriptase can only be generated and shed by those cells able to activate matriptase and in a rough correlation with the levels of matriptase protein. While HAI-2 can potently inhibit matriptase, the levels of active matriptase are not proportionally suppressed in those cells with high HAI-2. Our survey suggests that matriptase proteolysis might aberrantly remain high in neoplastic B-cells regardless of the levels of HAI-2.


Assuntos
Linfócitos B/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Glicoproteínas de Membrana/biossíntese , Proteólise/efeitos dos fármacos , Serina Endopeptidases/metabolismo , Linfócitos B/metabolismo , Linhagem Celular Tumoral , Humanos , Glicoproteínas de Membrana/metabolismo , Serina Endopeptidases/biossíntese
19.
J Vet Pharmacol Ther ; 42(2): 197-206, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30350369

RESUMO

Sanguinarine (SA) and chelerythrine (CHE) are the main active components of the phytogenic livestock feed additive, Sangrovit®. However, little information is available on the pharmacokinetics of Sangrovit® in poultry. The goal of this work was to study the pharmacokinetics of SA, CHE, and their metabolites, dihydrosanguinarine (DHSA) and dihydrochelerythrine (DHCHE), in 10 healthy female broiler chickens following oral (p.o.) administration of Sangrovit® and intravenous (i.v.) administration of a mixture of SA and CHE. The plasma samples were processed using two different simple protein precipitation methods because the parent drugs and metabolites are stable under different pH conditions. The absorption and metabolism of SA following p.o. administration were fast, with half-life (t1/2 ) values of 1.05 ± 0.18 hr and 0.83 ± 0.10 hr for SA and DHSA, respectively. The maximum concentration (Cmax ) of DHSA (2.49 ± 1.4 µg/L) was higher that of SA (1.89 ± 0.8 µg/L). The area under the concentration vs. time curve (AUC) values for SA and DHSA were 9.92 ± 5.4 and 6.08 ± 3.49 ng/ml hr, respectively. Following i.v. administration, the clearance (CL) of SA was 6.79 ± 0.63 (L·h-1 ·kg-1 ) with a t1/2 of 0.34 ± 0.13 hr. The AUC values for DHSA and DHCHE were 7.48 ± 1.05 and 0.52 ± 0.09 (ng/ml hr), respectively. These data suggested that Sangrovit® had low absorption and bioavailability in broiler chickens. The work reported here provides useful information on the pharmacokinetic behavior of Sangrovit® after p.o. and i.v. administration in broiler chickens, which is important for the evaluation of its use in poultry.


Assuntos
Benzofenantridinas/farmacocinética , Galinhas/metabolismo , Isoquinolinas/farmacocinética , Administração Oral , Animais , Benzofenantridinas/administração & dosagem , Benzofenantridinas/sangue , Galinhas/sangue , Cromatografia Líquida de Alta Pressão/veterinária , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/farmacocinética , Feminino , Meia-Vida , Injeções Intravenosas/veterinária , Isoquinolinas/administração & dosagem , Isoquinolinas/sangue , Espectrometria de Massas/veterinária
20.
Anal Chem ; 90(3): 1566-1571, 2018 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-29257684

RESUMO

Containing an ensemble of nitrogen-vacancy centers in crystal matrices, fluorescent nanodiamonds (FNDs) are a new type of photostable markers that have found wide applications in light microscopy. The nanomaterial also has a dense carbon core, making it visible to electron microscopy. Here, we show that FNDs encapsulated in biotinylated lipids (bLs) are useful for subdiffraction imaging of antigens on cell surface with correlative light-electron microscopy (CLEM). The lipid encapsulation enables not only good dispersion of the particles in biological buffers but also high specific labeling of live cells. By employing the bL-encapsulated FNDs to target CD44 on HeLa cell surface through biotin-mediated immunostaining, we obtained the spatial distribution of these antigens by CLEM with a localization accuracy of ∼50 nm in routine operations. A comparative study with dual-color imaging, in which CD44 was labeled with FND and MICA/MICB was labeled with Alexa Fluor 488, demonstrated the superior performance of FNDs as fluorescent fiducial markers for CLEM of cell surface antigens.


Assuntos
Antígenos de Superfície/química , Corantes Fluorescentes/química , Luz , Nanoestruturas/química , Células HeLa , Humanos , Microscopia Eletrônica , Estrutura Molecular , Tamanho da Partícula , Propriedades de Superfície
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