Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 49
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Small ; 20(11): e2305459, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37922532

RESUMEN

Electrocatalyst engineering from the atomic to macroscopic level of electrocatalysts is one of the most powerful routes to boost the performance of electrochemical devices. However, multi-scale structure engineering mainly focuses on the range of atomic-to-particle scale such as hierarchical porosity engineering, while catalyst engineering at the macroscopic level, such as the arrangement configuration of nanoparticles, is often overlooked. Here, a 2D carbon polyhedron array with a multi-scale engineered structure via facile chemical etching, ice-templating induced self-assembly, and high-temperature pyrolysis processes is reported. Controlled phytic acid etching of the carbon precursor introduces homogeneous atomic phosphorous and nitrogen doping, as well as a well-defined mesoporous structure. Subsequent ice-templated self-assembly triggers the formation of a 2D particle array superstructure. The atomic-level doping gives rise to high intrinsic activity, while the well-engineered porous structure and particle arrangement addresses the mass transport limitations at the microscopic particle level and macroscopic electrode level. As a result, the as-prepared electrocatalyst delivers outstanding performance toward oxygen reduction reaction in both acidic and alkaline media, which is better than recently reported state-of-the-art metal-free electrocatalysts. Molecular dynamics simulation together with extensive characterizations indicate that the performance enhancement originates from multi-scale structural synergy.

2.
Virol J ; 21(1): 114, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38778344

RESUMEN

BACKGROUND: EV71 is one of the important pathogens of Hand-foot-and-mouth disease (HFMD), which causes serious neurological symptoms. Several studies have speculated that there will be interaction between 5'UTR and 3D protein. However, whether 5'UTR interacts with the 3D protein in regulating virus replication has not been clarified. METHODS: Four 5'UTR mutation sites (nt88C/T, nt90-102-3C, nt157G/A and nt574T/A) and two 3D protein mutation sites (S37N and R142K) were mutated or co-mutated using virulent strains as templates. The replication of these mutant viruses and their effect on autophagy were determined. RESULTS: 5'UTR single-point mutant strains, except for EGFP-EV71(nt90-102-3C), triggered replication attenuation. The replication ability of them was weaker than that of the parent strain the virulent strain SDLY107 which is the fatal strain that can cause severe neurological complications. While the replication level of the co-mutant strains showed different characteristics. 5 co-mutant strains with interaction were screened: EGFP-EV71(S37N-nt88C/T), EGFP-EV71(S37N-nt574T/A), EGFP-EV71(R142K-nt574T/A), EGFP-EV71(R142K-nt88C/T), and EGFP-EV71(R142K-nt157G/A). The results showed that the high replicative strains significantly promoted the accumulation of autophagosomes in host cells and hindered the degradation of autolysosomes. The low replicative strains had a low ability to regulate the autophagy of host cells. In addition, the high replicative strains also significantly inhibited the phosphorylation of AKT and mTOR. CONCLUSIONS: EV71 5'UTR interacted with the 3D protein during virus replication. The co-mutation of S37N and nt88C/T, S37N and nt574T/ A, R142K and nt574T/A induced incomplete autophagy of host cells and promoted virus replication by inhibiting the autophagy pathway AKT-mTOR. The co-mutation of R142K and nt88C/T, and R142K and nt157G/A significantly reduced the inhibitory effect of EV71 on the AKT-mTOR pathway and reduced the replication ability of the virus.


Asunto(s)
Regiones no Traducidas 5' , Enterovirus Humano A , Proteínas Proto-Oncogénicas c-akt , Serina-Treonina Quinasas TOR , Replicación Viral , Enterovirus Humano A/genética , Enterovirus Humano A/fisiología , Enterovirus Humano A/patogenicidad , Regiones no Traducidas 5'/genética , Humanos , Serina-Treonina Quinasas TOR/metabolismo , Serina-Treonina Quinasas TOR/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Autofagia , Animales , Proteínas no Estructurales Virales/genética , Proteínas no Estructurales Virales/metabolismo , Transducción de Señal , Chlorocebus aethiops , Mutación , Línea Celular , Células Vero
3.
Nature ; 543(7644): 234-238, 2017 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-28199307

RESUMEN

The semiconductor industry is increasingly of the view that Moore's law-which predicts the biennial doubling of the number of transistors per microprocessor chip-is nearing its end. Consequently, the pursuit of alternative semiconducting materials for nanoelectronic devices, including single-walled carbon nanotubes (SWNTs), continues. Arrays of horizontal nanotubes are particularly appealing for technological applications because they optimize current output. However, the direct growth of horizontal SWNT arrays with controlled chirality, that would enable the arrays to be adapted for a wider range of applications and ensure the uniformity of the fabricated devices, has not yet been achieved. Here we show that horizontal SWNT arrays with predicted chirality can be grown from the surfaces of solid carbide catalysts by controlling the symmetries of the active catalyst surface. We obtained horizontally aligned metallic SWNT arrays with an average density of more than 20 tubes per micrometre in which 90 per cent of the tubes had chiral indices of (12, 6), and semiconducting SWNT arrays with an average density of more than 10 tubes per micrometre in which 80 per cent of the nanotubes had chiral indices of (8, 4). The nanotubes were grown using uniform size Mo2C and WC solid catalysts. Thermodynamically, the SWNT was selectively nucleated by matching its structural symmetry and diameter with those of the catalyst. We grew nanotubes with chiral indices of (2m, m) (where m is a positive integer), the yield of which could be increased by raising the concentration of carbon to maximize the kinetic growth rate in the chemical vapour deposition process. Compared to previously reported methods, such as cloning, seeding and specific-structure-matching growth, our strategy of controlling the thermodynamics and kinetics offers more degrees of freedom, enabling the chirality of as-grown SWNTs in an array to be tuned, and can also be used to predict the growth conditions required to achieve the desired chiralities.

4.
Nano Lett ; 22(5): 2147-2154, 2022 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-35041434

RESUMEN

To be considered as a promising candidate for mimicking biological nanochannels, carbon nanotubes (CNTs) have been used to explore the mass transport phenomena in recent years. In this study, the single nucleotide transport phenomena are comparatively studied using individual CNTs with a length of ∼15 µm and diameters ranging from 1.5 to 2.5 nm. In the case of CNTs with a diameter of 1.57-1.98 nm, the current traces of nucleotide transport are independent with the metallicity of CNTs and consist of single peak current pulses, whereas extraordinary stepwise current signals are observed in CNT with a diameter of 2.33 nm. It suggests that there is only one molecule in the nanochannel at a time until the diameter of CNT increases to 2.33 nm. Furthermore, it also demonstrates that the single nucleotides can be identified statistically according to their current pulses, indicating the potential application of CNT-based sensors for nucleotides identification.


Asunto(s)
Nanotubos de Carbono , Nucleótidos
5.
Opt Express ; 29(21): 32833-32841, 2021 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-34809106

RESUMEN

In this study, a long-distance phase-sensitive optical time domain reflectometry (Φ-OTDR) with a flexible frequency response based on time division multiplexing is proposed and experimentally demonstrated. Distributed flexible frequency vibration sensing over long distance can be realized by reconfiguring the system layout in a time-division-multiplexed manner by re-routing the Rayleigh backscattered signals for segmented processing with extra erbium-doped fiber amplifiers added only instead of any other complex signal amplification or pulse modulation mechanisms. Through time-division-multiplexed reconfiguration, the tradeoff between sensing distance and vibration frequency response in Φ-OTDR system is largely relieved. Compared with the traditional system layout, the proposed system allows a flexible frequency response in each sensing fiber segment without any crosstalk among them. In experiments, distributed vibration sensing with a frequency response up to 4.5 kHz is achieved over a sensing distance of 60km by the proposed system, which is not possible in a conventional Φ-OTDR system. Furthermore, the frequency response flexibility of the proposed system is further verified by successfully identifying a vibration event with a frequency of up to 20 kHz at the end of a 52-km-long fiber.

6.
Med Sci Monit ; 27: e929149, 2021 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-33608494

RESUMEN

BACKGROUND This retrospective study aimed to identify the factors associated with successful surgical correction of thoracic kyphosis (TK) in 43 patients with adolescent idiopathic scoliosis (AIS) with Lenke type 1 curvature, in which the major curve with the largest Cobb angle was mainly in the thoracic region. MATERIAL AND METHODS We collected data from patients with Lenke 1 AIS. The following parameters were measured: Cobb angle, side-bending Cobb angle, cervical lordosis (CL), TK, lumbar lordosis (LL), pelvic incidence (PI), sacral slope (SS), pelvic tilt (PT), the sagittal vertical axis (SVA), the center of a C7 plumb line to the center sacral vertical line (C7-CSVL), correction rate, Ponte osteotomy, flexibility, and screw density. Univariate analysis and multivariate logistic regression analyses were performed. RESULTS Among the 43 cases analyzed, the mean postoperative Cobb angle at the last follow-up, C7-CSVL, SVA, CL, TK, LL, PI, SS, and PT were respectively 21.33±9.47°, 10.41±8.45 mm, 19.68±14.33 mm, 16.19±7.45°, 23.12±7.45°, 50.33±11.37°, 49.70±9.83°, 39.42±8.11°, and 10.16±6.63°. Univariate analysis suggested that preoperative TK, preoperative LL, and Ponte osteotomy were statistically significant (P<0.05), and multivariate analysis suggested that preoperative LL and Ponte osteotomy were statistically significant (P<0.05). CONCLUSIONS The results of this study demonstrated that preoperative TK, preoperative LL, and Ponte osteotomy were related factors for maintaining normal TK. Multivariate analysis suggested that preoperative LL and the use of Ponte osteotomy with full-thickness segmental resection of the spinal posterior column resulted in the successful surgical correction of TK in patients with AIS with Lenke type 1 curvature.


Asunto(s)
Enfermedad de Scheuermann/cirugía , Enfermedad de Scheuermann/terapia , Escoliosis/cirugía , Adolescente , Vértebras Cervicales/cirugía , Niño , Femenino , Humanos , Cifosis/cirugía , Vértebras Lumbares/cirugía , Masculino , Osteotomía/métodos , Periodo Posoperatorio , Equilibrio Postural/fisiología , Postura/fisiología , Estudios Retrospectivos , Enfermedad de Scheuermann/rehabilitación , Fusión Vertebral/métodos , Vértebras Torácicas/cirugía
7.
J Exp Zool B Mol Dev Evol ; 332(1-2): 17-25, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30680935

RESUMEN

B-cell lymphoma-6 (Bcl6) is a transcriptional repressor that plays important roles in various physiological activities such as innate and adaptive immune response, lymphocyte differentiation, and cell cycle regulation in mammals. Two homologs of Bcl6a, namely Bcl6aa and Bcl6ab, are identified in teleost fish including medaka Oryzias latipes. The expression profiles of bcl6aa and bcl6ab in medaka were studied using reverse-transcription polymerase chain reaction and in situ hybridization. The transcripts of bcl6aa and bcl6ab were detected from very early embryos such as the four-cell stage until hatching. Bcl6aa and bcl6ab were clearly detected in the embryonic body from 5 days postfertilization onward by in situ hybridization. Bcl6aa was specifically expressed in the retina, whereas bcl6ab was expressed in entire embryonic body. The results referred to that both bcl6aa and bcl6ab originate maternally in the zygotes and may play major roles in embryogenesis of medaka. The transcripts of bcl6aa and bcl6ab were detected in all examined adult tissues, including immune organs such as the gill, spleen, kidney, liver, and intestine. The expression of bcl6aa and bcl6ab in the liver, spleen, head-kidney, and intestine could be upregulated or downregulated by lipopolysaccharide and polyriboinosinic-polyribocytidylic acid. These results indicate that both bcl6aa and bcl6ab may be involved in immune response in medaka.


Asunto(s)
Proteínas de Peces/metabolismo , Lipopolisacáridos/farmacología , Oryzias/metabolismo , Poli I-C/farmacología , Proteínas Represoras/metabolismo , Animales , Proteínas de Peces/genética , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Regulación del Desarrollo de la Expresión Génica/fisiología , Hibridación in Situ , Oryzias/embriología , Oryzias/genética , Filogenia , Proteínas Represoras/genética
8.
Gen Comp Endocrinol ; 277: 30-37, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-30395804

RESUMEN

Hepatitis A virus cellular receptor2 (Havcr2) also named T-cell immunoglobulin and mucin domain containing-3 (Tim-3) was initially described as a T helper 1-specific cell surface protein, a member of Tim family implicated in the regulating process of adaptive and innate immune responses. Here, medaka (Oryzias latipes) Havcr2 (OlHavcr2) was isolated and characterized. Unlike other Havcr2 proteins, OlHavcr2 possesses two Ig-like domains but lacks cytoplasmic and transmembrane domains. RT-PCR results revealed that OlHavcr2 mRNA was expressed strongly in the liver, moderately in the intestine, heart and ovary, and weakly in the muscle, gill, brain, eye, spleen, and testis. OlHavcr2 expression begun from gastrula stage and was maintained until hatching. The signal of OlHavcr2 was mainly identified in the blood system in the yolk sac by in situ hybridization. These results indicated that OlHavcr2 is expressed ubiquitously in adult tissues, and is a zygotic gene expressed from gastrula onwards in embryogenesis. OlHavcr2 may play a significant role in the blood system of medaka. In the immune organs, OlHavcr2 expression was affected by the immune stimulants, lipopolysaccharide and poly I:C, suggesting that OlHavcr2 was involved in innate immunity and adaptive immunity in medaka.


Asunto(s)
Proteínas de Peces/genética , Perfilación de la Expresión Génica , Oryzias/genética , Envejecimiento/genética , Animales , Desarrollo Embrionario/genética , Femenino , Proteínas de Peces/química , Proteínas de Peces/metabolismo , Regulación del Desarrollo de la Expresión Génica , Masculino , Oryzias/inmunología , Filogenia
9.
Int J Neurosci ; 126(12): 1112-9, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26707920

RESUMEN

PURPOSE: Preoperative embolization of meningiomas decreases intraoperative bleeding and shortens operation time. However, in meningiomas predominantly vascularized by the internal carotid artery (ICA) or vertebral artery (VA) branches, embolization of external carotid artery feeder branches may lead to a hemodynamic increase in blood supply from the ICA or VA, whereas embolization of ICA or VA feeder branches with particle embolic agents may be associated with complications. This study investigated the safety and efficacy of Glubran, a liquid embolic agent, for the embolization of this type of meningioma compared with polyvinyl-alcohol (PVA) particles. MATERIALS AND METHODS: From January 2006 to June 2015, 157 consecutive patients (98 females; mean age = 48.3 years) who suffered from meningiomas and were preoperatively referred for embolization were retrospectively analyzed. Glubran (n = 40) and PVA (n = 55) were used to devascularize tumors. Sixty-two patients were not embolized because of dangerous anastomosis or other tumor characteristics. Intraoperative blood loss, intraoperative time, degree of angiographic devascularization and embolization-related complications were analyzed. RESULTS: The intraoperative blood loss and operative time were significantly lower in the Glubran-embolized versus non-embolized group. Furthermore, Glubran embolization significantly reduced intraoperative blood loss and operative time for meningiomas that received their primary blood supply from the ICA and/or VA compared with PVA embolization. CONCLUSIONS: Preoperative meningioma embolization with Glubran decreases intraoperative blood loss and operative time. Furthermore, embolization with Glubran produces more effective devascularization compared with PVA for meningiomas supplied by the ICA and/or VA. Thus, Glubran may represent a better embolic agent for this meningioma subtype.


Asunto(s)
Cianoacrilatos/administración & dosificación , Embolización Terapéutica/métodos , Neoplasias Meníngeas/irrigación sanguínea , Neoplasias Meníngeas/cirugía , Meningioma/irrigación sanguínea , Meningioma/cirugía , Alcohol Polivinílico/administración & dosificación , Adulto , Anciano , Arteria Carótida Interna/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Estadísticas no Paramétricas , Resultado del Tratamiento , Arteria Vertebral/cirugía
10.
J Neuroinflammation ; 12: 61, 2015 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-25890011

RESUMEN

BACKGROUND: Mesenchymal stem cells (MSCs) are well known having beneficial effects on intracerebral hemorrhage (ICH) in previous studies. The therapeutic mechanisms are mainly to investigate proliferation, differentiation, and immunomodulation. However, few studies have used MSCs to treat blood-brain barrier (BBB) leakage after ICH. The influence of MSCs on the BBB and its related mechanisms were investigated when MSCs were transplanted into rat ICH model in this study. METHODS: Adult male Sprague-Dawley (SD) rats were randomly divided into sham-operated group, PBS-treated (ICH + PBS) group, and MSC-treated (ICH + MSC) group. ICH was induced by injection of IV collagenase into the rats' brains. MSCs were transplanted intravenously into the rats 2 h after ICH induction in MSC-treated group. The following factors were compared: inflammation, apoptosis, behavioral changes, inducible nitric oxide synthase (iNOS), matrix metalloproteinase 9 (MMP-9), peroxynitrite (ONOO(-)), endothelial integrity, brain edema content, BBB leakage, TNF-α stimulated gene/protein 6 (TSG-6), and nuclear factor-κB (NF-κB) signaling pathway. RESULTS: In the ICH + MSC group, MSCs decreased the levels of proinflammatory cytokines and apoptosis, downregulated the density of microglia/macrophages and neutrophil infiltration at the ICH site, reduced the levels of iNOS and MMP-9, attenuated ONOO(-) formation, and increased the levels of zonula occludens-1 (ZO-1) and claudin-5. MSCs also improved the degree of brain edema and BBB leakage. The protective effect of MSCs on the BBB in ICH rats was possibly invoked by increased expression of TSG-6, which may have suppressed activation of the NF-κB signaling pathway. The levels of iNOS and ONOO(-), which played an important role in BBB disruption, decreased due to the inhibitory effects of TSG-6 on the NF-κB signaling pathway. CONCLUSIONS: Our results demonstrated that intravenous transplantation of MSCs decreased the levels of ONOO(-) and degree of BBB leakage and improved neurological recovery in a rat ICH model. This strategy may provide a new insight for future therapies that aim to prevent breakdown of the BBB in patients with ICH and eventually offer therapeutic options for ICH.


Asunto(s)
Barrera Hematoencefálica/fisiopatología , Hemorragia Cerebral/patología , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/fisiología , Animales , Encéfalo/metabolismo , Encéfalo/patología , Edema Encefálico/etiología , Moléculas de Adhesión Celular/uso terapéutico , Citocinas/metabolismo , Modelos Animales de Enfermedad , Regulación de la Expresión Génica/fisiología , Masculino , Metaloproteinasa 9 de la Matriz/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Ácido Peroxinitroso/metabolismo , Ratas , Ratas Sprague-Dawley , Transducción de Señal/fisiología , Factores de Tiempo
11.
J Stroke Cerebrovasc Dis ; 24(8): 1951-6, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26082343

RESUMEN

BACKGROUND: Management of intracranial basilar dissecting aneurysms has been controversial and challenging, and surgical and conservative treatments usually have a bad prognosis. Our study aimed at evaluating the outcomes of endovascular treatment for these lesions and exploring the predictors of favorable outcome. METHODS: We retrospectively reviewed 50 consecutive patients with basilar dissecting aneurysms from January 2006 to January 2013. Twenty-four patients underwent stent-assisted coiling whereas 26 patients underwent conservative treatment. Follow-up outcomes were evaluated using modified Rankin Scale (mRS) score. RESULTS: Of the patients treated with stent-assisted coiling, 20 patients had a favorable outcome (mRS score, 0-1), post-treatment recurrence occurred in 3 patients, 1 had rebleeding, and 2 had no rebleeding. Of the patients treated with conservative therapy (observation or anticoagulation), 10 patients had an unfavorable outcome, 2 patients with ruptured aneurysms developed rebleeding, and 8 patients had poor outcome because of infarct progression. Stent-assisted coiling group had a more favorable outcome than the conservatively treated group (83.3% versus 55.2%, P = .019). Initial complete obliteration was related to the favorable outcome in endovascular-treated group (P = .042). Stent placement was the only independent predictor of favorable outcome in the logistic regression analysis (P = .030; odds ratio = 5.828; 95% confidence interval, 1.192-28.503). CONCLUSIONS: Patients with basilar artery dissecting aneurysms treated with stent-assisted coiling had a more favorable outcome than the conservatively treated patients. Stent placement and initial complete occlusion were the favorable factors in patients with basilar dissecting aneurysm.


Asunto(s)
Disección Aórtica/terapia , Embolización Terapéutica/métodos , Aneurisma Intracraneal/terapia , Resultado del Tratamiento , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Disección Aórtica/complicaciones , Disección Aórtica/diagnóstico , Angiografía Cerebral , Niño , Femenino , Estudios de Seguimiento , Humanos , Aneurisma Intracraneal/complicaciones , Aneurisma Intracraneal/diagnóstico , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Stents , Adulto Joven
12.
J Stroke Cerebrovasc Dis ; 24(9): 2134-42, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26150084

RESUMEN

BACKGROUND: Isolated dissecting aneurysms of the posterior inferior cerebellar artery (PICA) are rare lesions, which carry high risk of rebleeding and mortality. However, the existing literature concerning predictors of outcome after endovascular treatment is limited and controversial. Our present study retrospectively reviewed and analyzed the clinical outcome of endovascular treatment-ruptured PICA-dissecting aneurysms and explored the predictors of outcome. METHODS: We retrospectively reviewed 17 consecutive patients with ruptured PICA dissecting aneurysms that underwent endovascular treatment from January 2003 to January 2014. Nine patients underwent selective coiling, whereas 7 patients underwent parent artery occlusion and 1 patient underwent stent-assisted coiling. Follow-up outcomes were evaluated using the modified Rankin Scale. The clinical outcomes of patients were categorized as favorable (modified Rankin Scale [mRS] score 0-1) or unfavorable (mRS score 2-6). RESULTS: Favorable outcomes (mRS score 0-1) were obtained in 13 of 17 patients. Post-treatment recurrence occurred in 1 patient with selective coiling in the 15-month follow-up, and the patient received stent-assisted coiling. The only patients with stent-assisted coiling developed PICA occlusion during follow-up. Aneurysm located in distal segment usually presented with intraventricular hemorrhage (P = .015). Hypertension, coexisting hydrocephalus, and time to operation (latter than 2 weeks) were associated with unfavorable outcome. CONCLUSIONS: Endovascular treatment of isolated dissecting aneurysm of PICA had excellent clinical outcomes, hypertension, coexisting hydrocephalus, and time to operation (latter than 2 weeks), which were associated with unfavorable outcome. Long-term follow-ups are necessary to provide stronger conclusions.


Asunto(s)
Disección Aórtica/patología , Disección Aórtica/cirugía , Arterias Cerebrales/patología , Procedimientos Endovasculares/métodos , Adulto , Anciano , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Angiografía Cerebral , Femenino , Estudios de Seguimiento , Humanos , Angiografía por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estadísticas no Paramétricas , Hemorragia Subaracnoidea/cirugía , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
13.
Infect Med (Beijing) ; 3(2): 100115, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38974347

RESUMEN

Hand, foot, and mouth disease (HFMD) is one of the most common class C infectious diseases, posing a serious threat to public health worldwide. Enterovirus A71 (EV-A71) and coxsackievirus A16 (CV-A16) have been regarded as the major pathogenic agents of HFMD; however, since an outbreak caused by coxsackievirus A6 (CV-A6) in France in 2008, CV-A6 has gradually become the predominant pathogen in many regions. CV-A6 infects not only children but also adults, and causes atypical clinical symptoms such as a more generalized rash, eczema herpeticum, high fever, and onychomadesis, which are different from the symptoms associated with EV-A71 and CV-A16. Importantly, the rate of genetic recombination of CV-A6 is high, which can lead to changes in virulence and the rapid evolution of other characteristics, thus posing a serious threat to public health. To date, no specific vaccines or therapeutics have been approved for CV-A6 prevention or treatment, hence it is essential to fully understand the relationship between recombination and evolution of this virus. Here, we systematically review the genetic recombination events of CV-A6 that have occurred worldwide and explore how these events have promoted virus evolution, thus providing important information regarding future HFMD surveillance and prevention.

14.
Oncol Res ; 32(5): 911-923, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38686054

RESUMEN

Photodynamic therapy (PDT) is a promising cancer treatment. This study investigated the antitumor effects and mechanisms of a novel photosensitizer meso-5-[ρ-diethylene triamine pentaacetic acid-aminophenyl]-10,15,20-triphenyl-porphyrin (DTP) mediated PDT (DTP-PDT). Cell viability, reactive oxygen species (ROS), and apoptosis were measured with a Cell Counting Kit-8 assay, DCFH-DA fluorescent probe, and Hoechst staining, respectively. Cell apoptosis- and autophagy-related proteins were examined using western blotting. RNA sequencing was used to screen differentially expressed mRNAs (DERs), and bioinformatic analysis was performed to identify the major biological events after DTP-PDT. Our results show that DTP-PDT inhibited cell growth and induced ROS generation in MCF-7 and SGC7901 cells. The ROS scavenger N-acetyl-L-cysteine (NAC) and the P38 MAPK inhibitor SB203580 alleviated DTP-PDT-induced cytotoxicity. DTP-PDT induced cell apoptosis together with upregulated Bax and downregulated Bcl-2, which could also be inhibited by NAC or SB203580. The level of LC3B-II, a marker of autophagy, was increased by DTP-PDT. A total of 3496 DERs were obtained after DTP-PDT. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses indicated that DERs included those involved in cytosolic ribosomes, the nuclear lumen, protein binding, cell cycle, protein targeting to the endoplasmic reticulum, and ribosomal DNA replication. Disease Ontology and Reactome enrichment analyses indicated that DERs were associated with a variety of cancers and cell cycle checkpoints. Protein-protein interaction results demonstrated that cdk1 and rps27a ranked in the top 10 interacting genes. Therefore, DTP-PDT could inhibit cell growth and induce cell apoptosis and autophagy, partly through ROS and the P38 MAPK signaling pathway. Genes associated with the cell cycle, ribosomes, DNA replication, and protein binding may be the key changes in DTP-PDT-mediated cytotoxicity.


Asunto(s)
Apoptosis , Fotoquimioterapia , Fármacos Fotosensibilizantes , Especies Reactivas de Oxígeno , Transcriptoma , Humanos , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/farmacología , Especies Reactivas de Oxígeno/metabolismo , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Porfirinas/farmacología , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Autofagia/efectos de los fármacos , Células MCF-7 , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Neoplasias/metabolismo , Neoplasias/genética , Perfilación de la Expresión Génica
15.
Comput Assist Surg (Abingdon) ; 29(1): 2345066, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38860617

RESUMEN

BACKGROUND: Machine learning (ML), a subset of artificial intelligence (AI), uses algorithms to analyze data and predict outcomes without extensive human intervention. In healthcare, ML is gaining attention for enhancing patient outcomes. This study focuses on predicting additional hospital days (AHD) for patients with cervical spondylosis (CS), a condition affecting the cervical spine. The research aims to develop an ML-based nomogram model analyzing clinical and demographic factors to estimate hospital length of stay (LOS). Accurate AHD predictions enable efficient resource allocation, improved patient care, and potential cost reduction in healthcare. METHODS: The study selected CS patients undergoing cervical spine surgery and investigated their medical data. A total of 945 patients were recruited, with 570 males and 375 females. The mean number of LOS calculated for the total sample was 8.64 ± 3.7 days. A LOS equal to or <8.64 days was categorized as the AHD-negative group (n = 539), and a LOS > 8.64 days comprised the AHD-positive group (n = 406). The collected data was randomly divided into training and validation cohorts using a 7:3 ratio. The parameters included their general conditions, chronic diseases, preoperative clinical scores, and preoperative radiographic data including ossification of the anterior longitudinal ligament (OALL), ossification of the posterior longitudinal ligament (OPLL), cervical instability and magnetic resonance imaging T2-weighted imaging high signal (MRI T2WIHS), operative indicators and complications. ML-based models like Lasso regression, random forest (RF), and support vector machine (SVM) recursive feature elimination (SVM-RFE) were developed for predicting AHD-related risk factors. The intersections of the variables screened by the aforementioned algorithms were utilized to construct a nomogram model for predicting AHD in patients. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve and C-index were used to evaluate the performance of the nomogram. Calibration curve and decision curve analysis (DCA) were performed to test the calibration performance and clinical utility. RESULTS: For these participants, 25 statistically significant parameters were identified as risk factors for AHD. Among these, nine factors were obtained as the intersection factors of these three ML algorithms and were used to develop a nomogram model. These factors were gender, age, body mass index (BMI), American Spinal Injury Association (ASIA) scores, magnetic resonance imaging T2-weighted imaging high signal (MRI T2WIHS), operated segment, intraoperative bleeding volume, the volume of drainage, and diabetes. After model validation, the AUC was 0.753 in the training cohort and 0.777 in the validation cohort. The calibration curve exhibited a satisfactory agreement between the nomogram predictions and actual probabilities. The C-index was 0.788 (95% confidence interval: 0.73214-0.84386). On the decision curve analysis (DCA), the threshold probability of the nomogram ranged from 1 to 99% (training cohort) and 1 to 75% (validation cohort). CONCLUSION: We successfully developed an ML model for predicting AHD in patients undergoing cervical spine surgery, showcasing its potential to support clinicians in AHD identification and enhance perioperative treatment strategies.


Asunto(s)
Vértebras Cervicales , Tiempo de Internación , Aprendizaje Automático , Espondilosis , Humanos , Masculino , Femenino , Vértebras Cervicales/cirugía , Vértebras Cervicales/diagnóstico por imagen , Persona de Mediana Edad , Tiempo de Internación/estadística & datos numéricos , Espondilosis/cirugía , Espondilosis/diagnóstico por imagen , Nomogramas , Anciano , Adulto , Algoritmos
16.
Carbohydr Polym ; 327: 121656, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38171677

RESUMEN

In recent years, renewable cellulose-based ion exchange membranes have emerged as promising candidates for capturing green, abundant osmotic energy. However, the low power density and structural/performance instability are challenging for such cellulose membranes. Herein, cellulose-molecule self-assembly engineering (CMA) is developed to construct environmentally friendly, durable, scalable cellulose membranes (CMA membranes). Such a strategy enables CMA membranes with ideal nanochannels (∼7 nm) and tailored channel lengths, which support excellent ion selectivity and ion fluxes toward high-performance osmotic energy harvesting. Finite element simulations also verified the function of tailored nanochannel length on osmotic energy conversion. Correspondingly, our CMA membrane shows a high-power density of 2.27 W/m2 at a 50-fold KCl gradient and super high voltage of 1.32 V with 30-pair CMA membranes (testing area of 22.2 cm2). In addition, the CMA membrane demonstrates long-term structural and dimensional integrity in saline solution, due to their high wet strength (4.2 MPa for N-CMA membrane and 0.5 MPa for P-CMA membrane), and correspondingly generates ultrastable yet high power density more than 100 days. The self-assembly engineering of cellulose molecules constructs high-performance ion-selective membranes with environmentally friendly, scalable, high wet strength and stability advantages, which guide sustainable nanofluidic applications beyond the blue energy.

17.
Biomol Biomed ; 24(2): 401-410, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-37897663

RESUMEN

This study focused on the development and validation of a diagnostic model to differentiate between spinal tuberculosis (STB) and pyogenic spondylitis (PS). We analyzed a total of 387 confirmed cases, out of which 241 were diagnosed with STB and 146 were diagnosed with PS. These cases were randomly divided into a training group (n = 271) and a validation group (n = 116). Within the training group, four machine learning (ML) algorithms (least absolute shrinkage and selection operator [LASSO], logistic regression analysis, random forest, and support vector machine recursive feature elimination [SVM-RFE]) were employed to identify distinctive variables. These specific variables were then utilized to construct a diagnostic model. The model's performance was subsequently assessed using the receiver operating characteristic (ROC) curves and the calibration curves. Finally, internal validation of the model was undertaken in the validation group. Our findings indicate that PS patients had an average platelet-to-neutrophil ratio (PNR) of 277.86, which was significantly higher than the STB patients' average of 69.88. The average age of PS patients was 54.71 years, older than the 48 years recorded for STB patients. Notably, the neutrophil-to-lymphocyte ratio (NLR) was higher in PS patients at 6.15, compared to the 3.46 NLR in STB patients. Additionally, the platelet volume distribution width (PDW) in PS patients was 0.2, compared to 0.15 in STB patients. Conversely, the mean platelet volume (MPV) was lower in PS patients at an average of 4.41, whereas STB patients averaged 8.31. Hemoglobin (HGB) levels were lower in PS patients at an average of 113.31 compared to STB patients' average of 121.64. Furthermore, the average red blood cell (RBC) count was 4.26 in PS patients, which was less than the 4.58 average observed in STB patients. After evaluation, seven key factors were identified using the four ML algorithms, forming the basis of our diagnostic model. The training and validation groups yielded area under the curve (AUC) values of 0.841 and 0.83, respectively. The calibration curves demonstrated a high alignment between the nomogram-predicted values and the actual measurements. The decision curve indicated optimal model performance with a threshold set between 2% and 88%. In conclusion, our model offers healthcare practitioners a reliable tool to efficiently and precisely differentiate between STB and PS, thereby facilitating swift and accurate diagnoses.


Asunto(s)
Espondiloartritis , Espondilitis , Tuberculosis de la Columna Vertebral , Humanos , Persona de Mediana Edad , Algoritmos , Aprendizaje Automático
18.
Microbiol Spectr ; 12(7): e0001824, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38757960

RESUMEN

Monkeypox virus (MPXV) poses a global health threat. Droplet digital PCR (ddPCR) holds potential as an accurate diagnostic tool for clinical microbiology. However, there is limited literature on the applicability of ddPCR in clinical settings. In this study, the clinical features of patients with MPXV during the initial outbreak in China in June 2023 were reviewed, and an optimized ddPCR method with dilution and/or inhibitor removal was developed to enhance MPXV detection efficiency. Eighty-two MPXV samples were tested from nine different clinical specimen types, including feces, urine, pharyngeal swabs, anal swabs, saliva, herpes fluid, crust, and semen, and the viral load of each specimen was quantified. A comparative analysis was performed with qPCR to assess sensitivity and specificity and to investigate the characteristics of MPXV infection by analyzing viral loads in different clinical specimens. Consequently, common pharyngeal and gastrointestinal symptoms were observed in patients with MPXV. The optimized ddPCR method demonstrated relatively high sensitivity for MPXV quantification in the clinical materials, with a limit of detection of 0.1 copies/µL. This was particularly evident in low-concentration samples like whole blood, semen, and urine. The optimized ddPCR demonstrated greater detection accuracy compared with normal ddPCR and qPCR, with an area under the curve (AUC) of 0.939. Except for crust samples, viral loads in the specimens gradually decreased as the disease progressed. Virus levels in feces and anal swabs kept a high detection rate at each stage of post-symptom onset, and feces and anal swabs samples may be suitable for clinical diagnosis and continuous monitoring of MPXV. IMPORTANCE: The ddPCR technique proved to be a sensitive and valuable tool for accurately quantifying MPXV viral loads in various clinical specimen types. The findings provided valuable insights into the necessary pre-treatment protocols for MPXV diagnosis in ddPCR detection and the potentially suitable sample types for collection. Therefore, such results can aid in comprehending the potential characteristics of MPXV infection and the usage of ddPCR in clinical settings.


Asunto(s)
Monkeypox virus , Sensibilidad y Especificidad , Carga Viral , Humanos , Carga Viral/métodos , Monkeypox virus/aislamiento & purificación , Monkeypox virus/genética , China , Mpox/diagnóstico , Mpox/virología , Masculino , Heces/virología , Femenino , Reacción en Cadena de la Polimerasa/métodos , Brotes de Enfermedades , Adulto , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos
19.
Emerg Microbes Infect ; 13(1): 2368217, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38865205

RESUMEN

Nipah virus (NiV), a highly pathogenic Henipavirus in humans, has been responsible for annual outbreaks in recent years. Experiments involving live NiV are highly restricted to biosafety level 4 (BSL-4) laboratories, which impedes NiV research. In this study, we developed transcription and replication-competent NiV-like particles (trVLP-NiV) lacking N, P, and L genes. This trVLP-NiV exhibited the ability to infect and continuously passage in cells ectopically expressing N, P, and L proteins while maintaining stable genetic characteristics. Moreover, the trVLP-NiV displayed a favourable safety profile in hamsters. Using the system, we found the NiV nucleoprotein residues interacting with viral RNA backbone affected viral replication in opposite patterns. This engineered system was sensitive to well-established antiviral drugs, innate host antiviral factors, and neutralizing antibodies. We then established a high-throughput screening platform utilizing the trVLP-NiV, leading to the identification of tunicamycin as a potential anti-NiV compound. Evidence showed that tunicamycin inhibited NiV replication by decreasing the infectivity of progeny virions. In conclusion, this trVLP-NiV system provided a convenient and versatile molecular tool for investigating NiV molecular biology and conducting antiviral drug screening under BSL-2 conditions. Its application will contribute to the development of medical countermeasures against NiV infections.


Asunto(s)
Infecciones por Henipavirus , Virus Nipah , Replicación Viral , Virus Nipah/fisiología , Virus Nipah/genética , Virus Nipah/efectos de los fármacos , Animales , Cricetinae , Humanos , Infecciones por Henipavirus/virología , Transcripción Genética , Virión/genética , Proteínas Virales/genética , Proteínas Virales/metabolismo , Antivirales/farmacología , Células Vero , Chlorocebus aethiops , Línea Celular , ARN Viral/genética
20.
Emerg Microbes Infect ; 13(1): 2300762, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38164794

RESUMEN

Ebola virus (EBOV) belongs to Filoviridae family possessing single-stranded negative-sense RNA genome, which is a serious threat to human health. Nowadays, no therapeutics have been proven to be successful in efficiently decreasing the mortality rate. RNA binding proteins (RBPs) are reported to participate in maintaining cell integrity and regulation of viral replication. However, little is known about whether and how RBPs participate in regulating the life cycle of EBOV. In our study, we found that RNA binding motif protein 4 (RBM4) inhibited the replication of EBOV in HEK293T and Huh-7 cells by suppressing viral mRNA production. Such inhibition resulted from the direct interaction between the RRM1 domain of RBM4 and the "CU" enrichment elements located in the PE1 and TSS of the 3'-leader region within the viral genome. Simultaneously, RBM4 could upregulate the expression of some cytokines involved in the host innate immune responses to synergistically exert its antiviral function. The findings therefore suggest that RBM4 might serve as a novel target of anti-EBOV strategy.


Asunto(s)
Ebolavirus , Fiebre Hemorrágica Ebola , Humanos , Ebolavirus/genética , ARN , Células HEK293 , Replicación Viral , Motivos de Unión al ARN , Genómica , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA