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1.
Nature ; 602(7895): 91-95, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35110762

RESUMEN

Polymers that extend covalently in two dimensions have attracted recent attention1,2 as a means of combining the mechanical strength and in-plane energy conduction of conventional two-dimensional (2D) materials3,4 with the low densities, synthetic processability and organic composition of their one-dimensional counterparts. Efforts so far have proven successful in forms that do not allow full realization of these properties, such as polymerization at flat interfaces5,6 or fixation of monomers in immobilized lattices7-9. Another frequently employed synthetic approach is to introduce microscopic reversibility, at the cost of bond stability, to achieve 2D crystals after extensive error correction10,11. Here we demonstrate a homogenous 2D irreversible polycondensation that results in a covalently bonded 2D polymeric material that is chemically stable and highly processable. Further processing yields highly oriented, free-standing films that have a 2D elastic modulus and yield strength of 12.7 ± 3.8 gigapascals and 488 ± 57 megapascals, respectively. This synthetic route provides opportunities for 2D materials in applications ranging from composite structures to barrier coating materials.

2.
Plant Physiol ; 196(2): 1489-1501, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38889048

RESUMEN

Transcriptional reprogramming is critical for plant immunity. Several calmodulin (CaM)-binding protein 60 (CBP60) family transcription factors (TFs) in Arabidopsis (Arabidopsis thaliana), including CBP60g, systemic acquired resistance deficient 1 (SARD1), CBP60a, and CBP60b, are critical for and show distinct roles in immunity. However, there are additional CBP60 members whose function is unclear. We report here that Arabidopsis CBP60c-f, 4 uncharacterized CBP60 members, play redundant roles with CBP60b in the transcriptional regulation of immunity responses, whose pCBP60b-driven expression compensates the loss of CBP60b. By contrast, neither CBP60g nor SARD1 is interchangeable with CBP60b, suggesting clade-specific functionalization. We further show that the function of CBP60b clade TFs relies on DNA-binding domains (DBDs) and CaM-binding domains, suggesting that they are downstream components of calcium signaling. Importantly, we demonstrate that CBP60s encoded in earliest land plant lineage Physcomitrium patens and Selaginella moellendorffii are functionally homologous to Arabidopsis CBP60b, suggesting that the CBP60b clade contains the prototype TFs of the CBP60 family. Furthermore, tomato and cucumber CBP60b-like genes rescue the defects of Arabidopsis cbp60b and activate the expression of tomato and cucumber SALICYLIC ACID INDUCTION DEFICIIENT2 (SID2) and ENHANCED DISEASE SUSCEPTIBILITY 1 (EDS1) genes, suggesting that immune response pathways centered on CBP60b are also evolutionarily conserved. Together, these findings suggest that CBP60b clade TFs are functionally conserved in evolution and positively mediate immunity.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Regulación de la Expresión Génica de las Plantas , Inmunidad de la Planta , Factores de Transcripción , Arabidopsis/genética , Arabidopsis/inmunología , Arabidopsis/metabolismo , Inmunidad de la Planta/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Enfermedades de las Plantas/inmunología , Enfermedades de las Plantas/genética , Filogenia , Proteínas de Unión a Calmodulina/genética , Proteínas de Unión a Calmodulina/metabolismo , Bryopsida/genética , Bryopsida/inmunología
3.
Mol Med ; 30(1): 84, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38867168

RESUMEN

BACKGROUND: Deep vein thrombosis (DVT) is a common vascular surgical disease caused by the coagulation of blood in the deep veins, and predominantly occur in the lower limbs. Endothelial progenitor cells (EPCs) are multi-functional stem cells, which are precursors of vascular endothelial cells. EPCs have gradually evolved into a promising treatment strategy for promoting deep vein thrombus dissolution and recanalization through the stimulation of various physical and chemical factors. METHODS: In this study, we utilized a mouse DVT model and performed several experiments including qRT-PCR, Western blot, tube formation, wound healing, Transwell assay, immunofluorescence, flow cytometry analysis, and immunoprecipitation to investigate the role of HOXD9 in the function of EPCs cells. The therapeutic effect of EPCs overexpressing HOXD9 on the DVT model and its mechanism were also explored. RESULTS: Overexpression of HOXD9 significantly enhanced the angiogenesis and migration abilities of EPCs, while inhibiting cell apoptosis. Additionally, results indicated that HOXD9 specifically targeted the HRD1 promoter region and regulated the downstream PINK1-mediated mitophagy. Interestingly, intravenous injection of EPCs overexpressing HOXD9 into mice promoted thrombus dissolution and recanalization, significantly decreasing venous thrombosis. CONCLUSIONS: The findings of this study reveal that HOXD9 plays a pivotal role in stimulating vascular formation in endothelial progenitor cells, indicating its potential as a therapeutic target for DVT management.


Asunto(s)
Modelos Animales de Enfermedad , Células Progenitoras Endoteliales , Proteínas de Homeodominio , Mitofagia , Neovascularización Fisiológica , Trombosis de la Vena , Animales , Células Progenitoras Endoteliales/metabolismo , Ratones , Trombosis de la Vena/metabolismo , Trombosis de la Vena/genética , Trombosis de la Vena/terapia , Proteínas de Homeodominio/metabolismo , Proteínas de Homeodominio/genética , Mitofagia/genética , Neovascularización Fisiológica/genética , Movimiento Celular , Masculino , Apoptosis , Humanos , Angiogénesis
4.
Nat Mater ; 22(12): 1453-1462, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37620646

RESUMEN

Robots have components that work together to accomplish a task. Colloids are particles, usually less than 100 µm, that are small enough that they do not settle out of solution. Colloidal robots are particles capable of functions such as sensing, computation, communication, locomotion and energy management that are all controlled by the particle itself. Their design and synthesis is an emerging area of interdisciplinary research drawing from materials science, colloid science, self-assembly, robophysics and control theory. Many colloidal robot systems approach synthetic versions of biological cells in autonomy and may find ultimate utility in bringing these specialized functions to previously inaccessible locations. This Perspective examines the emerging literature and highlights certain design principles and strategies towards the realization of colloidal robots.

5.
Zhongguo Zhong Yao Za Zhi ; 49(16): 4537-4544, 2024 Aug.
Artículo en Zh | MEDLINE | ID: mdl-39307790

RESUMEN

Chinese patent medicine constitutes a vital segment of the traditional Chinese medicine(TCM) industry and stands as a significant emblem of TCM modernization. At present, the quality stability between batches of Chinese patent medicine preparations has become a pivotal factor directly restricting the high-quality development of the TCM industry. Consequently, addressing the homogeneity of Chinese patent medicines, this paper proposes a research scheme of homogenization feeding. It systematically elaborates on the object and pretreatment of homogenization, operational procedures of homogenization feeding, selection of homogenization evaluation indices, homogenization feeding algorithm, and homogenization feeding process. With the key quality control indicators as the homogenization target, the homogenization feeding process and its quality analysis were discussed. Finally, a demonstration strategy for homogenization feeding of Chinese patent medicine was formed, providing the scientific basis for advancing the research of quality consistency across batches of Chinese patent medicine preparations.


Asunto(s)
Medicamentos Herbarios Chinos , Medicina Tradicional China , Control de Calidad , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/normas , Medicamentos sin Prescripción/química , Composición de Medicamentos/métodos
6.
Bioorg Chem ; 119: 105494, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34836643

RESUMEN

Both HIV and DENV are serious threats to human life, health and social economy today. So far, no vaccine for either HIV or DENV has been developed successfully. The research on anti-HIV or DENV drugs is still of great significance. In this study we developed a series of novel 2-Aryl-1H-pyrazole-S-DABOs with C6-strucutral optimizations as potent NNRTIs, among which, 8 compounds had low cytotoxicity and EC50 values in the range of 0.0508 âˆ¼ 0.0966 µM, and their selectivity index was SI > 1415 âˆ¼ 3940. In particular, two compounds 4a and 4b were identified to have good inhibitory effects on DENV of four serotypes. The EC50 of compound 4a and 4b against DENV-II (13.2 µM and 9.23 µM, respectively) were better than that of the positive control ribavirin (EC50 = 40.78 µM). In addition, the effect of C-6 substituents on the anti-HIV or anti-DENV activity of these compounds was also discussed.


Asunto(s)
Antivirales/farmacología , Virus del Dengue/efectos de los fármacos , VIH-1/efectos de los fármacos , Pirazoles/farmacología , Antivirales/síntesis química , Antivirales/química , Relación Dosis-Respuesta a Droga , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Pirazoles/síntesis química , Pirazoles/química , Relación Estructura-Actividad
7.
BMC Musculoskelet Disord ; 23(1): 964, 2022 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-36348396

RESUMEN

BACKGROUND: Medial epicondyle fractures are one of the more common humerus fractures, but humeral medial condyle fracture (HMCF) is rare. Nonunion of medial humeral condyle fractures due to functional exercise is less common. CASE PRESENTATION: We report a 5-year-old patient with a nonunion HMCF due to excessive functional exercise, who bruised the elbow 1 year ago and had no positive findings on all imaging studies. On this physical examination, there was a snapping and palpable lump in the elbow joint during movement, but the patient did not feel any discomfort and the range of motion of the joint was normal. X rays and computed tomography (CT) showed that the left HMCF was discontinuous, the broken ends were dislocated, and the joint alignment was poor. Open reduction (OR) and screw fixation was used during the operation, and the patient recovered well at 3-month follow-up. CONCLUSIONS: The rarity and low radiographic appearance of displaced HMCF are easily overlooked and can eventually lead to nonunion HMCF, especially when radiographically difficult to visualize before age 5 years. Therefore, regardless of whether there are signs or imaging abnormalities in the growth process of adolescents, they should be vigilant, shorten the time interval for re-examination, and early detection and timely treatment can avoid some complications caused by this.


Asunto(s)
Articulación del Codo , Fracturas no Consolidadas , Fracturas del Húmero , Adolescente , Humanos , Preescolar , Articulación del Codo/cirugía , Fijación Interna de Fracturas/métodos , Fracturas del Húmero/diagnóstico por imagen , Fracturas del Húmero/etiología , Fracturas del Húmero/cirugía , Húmero/cirugía , Fracturas no Consolidadas/diagnóstico por imagen , Fracturas no Consolidadas/etiología , Fracturas no Consolidadas/cirugía , Rango del Movimiento Articular , Resultado del Tratamiento
8.
Molecules ; 27(19)2022 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-36234872

RESUMEN

Bisphenol A epoxy resin cured with a mixture of dimerized and trimerized fatty acids is the first epoxy vitrimer and has been extensively studied. However, the cure behavior and thermal and mechanical properties of this epoxy vitrimer depend on the epoxy/acid stoichiometry. To address these issues, epoxy vitrimers with three epoxy/acid stoichiometries (9:11, 1:1 and 11:9) were prepared and recycled four times. Differential scanning calorimetry (DSC) was used to study the cure behavior of the original epoxy vitrimers. The dynamic mechanical properties and mechanical performance of the original and recycled epoxy vitrimers were investigated by using dynamic mechanical analysis (DMA) and a universal testing machine. Furthermore, the reaction mechanism of epoxy vitrimer with different epoxy/acid stoichiometry was interpreted. With an increase in the epoxy/acid ratio, the reaction rate, swelling ratio, glass transition temperature and mechanical properties of the original epoxy vitrimers decreased, whereas the gel content increased. The recycling decreased the swelling ratio and elongation at break of the original epoxy vitrimers. Moreover, the elongation at break of the recycled epoxy vitrimers decreased with the epoxy/acid ratio at the same recycling time. However, the gel content, tensile strength and toughness of the original epoxy vitrimers increased after the recycling. The mechanical properties of epoxy vitrimers can be tuned with the variation in the epoxy/acid stoichiometry.


Asunto(s)
Ácidos , Resinas Epoxi , Resinas Epoxi/química , Ácidos Grasos/química , Temperatura , Resistencia a la Tracción
9.
Molecules ; 27(20)2022 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-36296653

RESUMEN

The application of crumb rubber from end-of-life tires and waste cooking oil (WCO) in road pavements is of significant importance from an economic and environmental viewpoint. However, the incorporation of crumb rubber greatly shortens the allowable construction time of epoxy asphalt binders due to the high viscosity of the epoxy asphalt rubber (EAR) binder and poor compatibility between crumb rubber and asphalt binder. To lower the viscosity of asphalt rubber, extend the allowable construction time and improve the compatibility of EAR binder, waste cooking oil (WCO) was introduced. The effect of WCO on the viscosity-time behavior, thermal stability, dynamic modulus, glass transitions, crosslink density, damping ability, compatibility, mechanical properties and phase separation of WCO-modified EAR binders was investigated by using the Brookfield viscometer, thermogravimetric analysis, dynamic mechanical analysis, universal testing machine and laser confocal microscopy. The test results demonstrated that the incorporation of WCO declined the viscosity and extended the allowable construction time of the unmodified EAR binder. The inclusion of WCO improved the compatibility between asphalt and crumb rubber and the damping ability and elongation at the break of the unmodified EAR binder. The presence of WCO had a marginal effect on the thermal stability of the unmodified EAR binder. Confocal microscopy observation revealed that asphalt rubber particles aggregated in the epoxy phase of the unmodified EAR binder. With the inclusion of WCO, co-continuous asphalt rubber particles became more spherical.


Asunto(s)
Culinaria , Hidrocarburos , Viscosidad , Resinas Epoxi
10.
BMC Cancer ; 21(1): 772, 2021 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-34217251

RESUMEN

BACKGROUND: Epidermal growth factor-like domain 7 (Egfl7), a recently identified secreted protein, was significantly increased in patients with HCC by our previous studies. However, its efficacy in the diagnosis of early HCC remains unknown. In this study, we therefore evaluate the efficacy of serum Egfl7 for early HCC diagnosis and compare it with alpha-fetoprotein (AFP). METHODS: Serum Egfl7 levels in testing cohort (1081 participants) and validation cohort (476 participants) were measured by a sandwich enzyme-linked immunoassay (ELISA). The cut-off value of Egfl7 was determined by Youden's index and the efficacies of Egfl7 and AFP in diagnosing early HCC were estimated by receiver operating characteristic (ROC). RESULTS: Serum Egfl7 was significantly elevated in patients with early HCC than all non-HCC controls in whatever Testing Cohort or Validation Cohort. In the Testing Cohort, ROC curves showed the optimum cut-off value of Egfl7 was 2610 ng/mL and Egfl7 showed a significantly higher sensitivity than AFP in discriminating early HCC from healthy individuals (77.4% vs. 65.3%, P = 0.0013) but the area under ROC (AUROC) and accuracy of Egfl7 and AFP were similar (0.860 vs. 0.868, P = 0.704; 80.2% vs. 83.8%, P = 0.184). In distinguishing patients with early HCC from patients with chronic liver disease (CLD), the AUROC, sensitivity, specificity and accuracy of Egfl7 were 0.800, 75.2, 71.7 and 73.5%, which were all significantly higher than AFP (0.675, 61.8, 62.0 and 61.9% in order). Egfl7 also showed a significant higher sensitivity and accuracy than AFP (76.6% vs. 64.0%, P = 0.0031; 79.9% vs. 66.1%, P < 0.0001) in differentiating early HCC patients from non-HCC individuals. Additionally, 70.8% of early HCC patients with negative AFP could be diagnosed by Egfl7 and the combined use of Egfl7 and AFP increased the sensitivity to 91.0%. These results were confirmed by a validation cohort. CONCLUSION: Egfl7 is a valuable serum marker in the diagnosis of early HCC and could complement the efficacy of AFP, especially in distinguishing early HCC from CLD and identifying patients with AFP-negative early HCC.


Asunto(s)
Proteínas de Unión al Calcio/metabolismo , Carcinoma Hepatocelular/genética , Familia de Proteínas EGF/metabolismo , Neoplasias Hepáticas/genética , Adulto , Anciano , Biomarcadores de Tumor/sangre , Carcinoma Hepatocelular/patología , Femenino , Humanos , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Adulto Joven
11.
Faraday Discuss ; 227: 213-232, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33443260

RESUMEN

A central ambition of the robotics field has been to increasingly miniaturize such systems, with perhaps the ultimate achievement being the synthetic microbe or cell sized machine. To this end, we have introduced and demonstrated prototypes of what we call colloidal state machines (CSMs) as particulate devices capable of integrating sensing, memory, and energy harvesting as well as other functions onto a single particle. One technique that we have introduced for creating CSMs based on 2D materials such as graphene or monolayer MoS2 is "autoperforation", where the nanometer-scale film is fractured around a designed strain field to produce structured particles upon liftoff. While CSMs have been demonstrated with functions such as memory, sensing, and energy harvesting, the property of locomotion has not yet been demonstrated. In this work, we introduce an inversion moulding technique compatible with autoperforation that allows for the patterning of an external catalytic surface that enables locomotion in an accompanying fuel bath. Optimal processing conditions for electroplating a catalytic Pt layer to one side of an autoperforated CSM are elucidated. The self-driven propulsion of the resulting Janus CSM in H2O2 is studied, including the average velocity, as a function of fluid surface tension and H2O2 concentration in the bath. Since machines have to encode for a specific task, this work summarizes efforts to create a microfluidic testbed that allows for CSM designs to be evaluated for the ultimate purpose of navigation through complex fluidic networks, such as the human circulatory system. We introduce two CSM designs that mimic aspects of human immunity to solve search and recruitment tasks in such environments. These results advance CSM design concepts closer to promising applications in medicine and other areas.


Asunto(s)
Grafito , Robótica , Catálisis , Humanos , Peróxido de Hidrógeno , Locomoción
12.
Mol Biol Rep ; 48(8): 6145-6150, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34331665

RESUMEN

N6-methyladenosine (m6A) is the most common form of internal RNA modification in eukaryotes. The dynamic regulation of m6A modification mainly rely on three proteases, installed by m6A methyltransferase, removed by m6A demethylase and recognized by m6A reader protein, which regulates the metabolism of RNA, thereby regulating the processes of cell proliferation, migration, invasion and apoptosis. Recently, a number of studies have found that m6A aberrant methylation in some eye diseases. This review was to summarize the recent research progress on the role of m6A modification in eye diseases and give a perspective on its prospective applications in eye diseases.


Asunto(s)
Adenosina/análogos & derivados , Oftalmopatías/metabolismo , Adenosina/genética , Adenosina/metabolismo , Adenosina/fisiología , Epigénesis Genética/genética , Oftalmopatías/genética , Humanos , Metilación , Metiltransferasas/metabolismo , ARN/metabolismo , ARN Mensajero/metabolismo
13.
BMC Musculoskelet Disord ; 22(1): 106, 2021 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-33485304

RESUMEN

BACKGROUND: The severe rigid deformity patients with pulmonary dysfunction could not tolerate complicated corrective surgery. Preoperative traction are used to reduce the curve magnitude and improve the pulmonary function before surgery, including halo-gravity traction (HGT) and halo-pelvic traction (HPT). The present study aimed to retrospectively compare the radiographic, pulmonary and clinical outcomes of preoperative HGT and HPT in severe rigid spinal deformity with respiratory dysfunction. METHODS: 81 cases of severe rigid kyphoscoliosis treated with preoperative traction prior to corrective surgery for spinal deformity between 2016 and 2019 were retrospectively reviewed. Two patient groups were compared, HPT group (N = 30) and HGT group (N = 51). Patient demographics, coronal and sagittal Cobb angles and correction rates, pulmonary function, traction time, osteotomy grade, and postoperative neurological complications were recorded for all cases. RESULTS: The coronal Cobb angle was corrected from 140.67 ± 2.63 to a mean of 120.17 ± 2.93° in the HGT group, and from 132.32 ± 4.96 to 87.59 ± 3.01° in the HPT group (mean corrections 15.33 ± 1.53 vs. 34.86 ± 3.11 %) (P = 0.001). The mean major sagittal curve decreased from 134.28 ± 3.77 to 113.03 ± 4.57° in the HGT group and from 129.60 ± 8.45 to 65.61 ± 7.86° in the HPT group (P < 0.001); the mean percentage corrections were 16.50 ± 2.13 and 44.09 ± 9.78 % (P < 0.001). A significant difference in the pulmonary function test results was apparent between the two groups; the mean improvements in the FVC% of the HGT and HPT groups were 6.76 ± 1.85 and 15.6 ± 3.47 % (P = 0.024). The HPT group tended to exhibit more FEV% improvement than the HGT group, but the difference was not significant (5.15 ± 2.27 vs. 11.76 ± 2.22 %, P = 0.91). CONCLUSIONS: Patients with severe rigid kyphoscoliosis who underwent preoperative HPT exhibited better radiographic correction of the deformity, and pulmonary function, and required fewer osteotomies compared to the HGT group. Thus, HPT may be useful for severe rigid spinal deformity patients with pulmonary dysfunction.


Asunto(s)
Cifosis , Escoliosis , Fusión Vertebral , Humanos , Cifosis/diagnóstico por imagen , Cifosis/cirugía , Cuidados Preoperatorios , Estudios Retrospectivos , Escoliosis/diagnóstico por imagen , Escoliosis/cirugía , Tracción , Resultado del Tratamiento
14.
Entropy (Basel) ; 23(12)2021 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-34945997

RESUMEN

In the continuous variable measurement-device-independent quantum key distribution (CV-MDI-QKD) protocol, both Alice and Bob send quantum states to an untrusted third party, Charlie, for detection through the quantum channel. In this paper, we mainly study the performance of the CV-MDI-QKD system using the noiseless linear amplifier (NLA). The NLA is added to the output of the detector at Charlie's side. The research results show that NLA can increase the communication distance and secret key rate of the CV-MDI-QKD protocol. Moreover, we find that the more powerful the improvement of the performance with the longer gain of NLA and the optimum gain is given under different conditions.

15.
BMC Neurol ; 20(1): 433, 2020 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-33246421

RESUMEN

BACKGROUND: Difficult procedures of severe rigid spinal deformity increase the risk of intraoperative neurological injury. Here, we aimed to investigate the preoperative and intraoperative risk factors for postoperative neurological complications when treating severe rigid spinal deformity. METHODS: One hundred seventy-seven consecutive patients who underwent severe rigid spinal deformity correction were assigned into 2 groups: the neurological complication (NC, 22 cases) group or non-NC group (155 cases). The baseline demographics, preoperative spinal cord functional classification, radiographic parameters (curve type, curve magnitude, and coronal/sagittal/total deformity angular ratio [C/S/T-DAR]), and surgical variables (correction rate, osteotomy type, location, shortening distance of the osteotomy gap, and anterior column support) were analyzed to determine the risk factors for postoperative neurological complications. RESULTS: Fifty-eight patients (32.8%) had intraoperative evoked potentials (EP) events. Twenty-two cases (12.4%) developed postoperative neurological complications. Age and etiology were closely related to postoperative neurological complications. The spinal cord functional classification analysis showed a lower proportion of type A, and a higher proportion of type C in the NC group. The NC group had a larger preoperative scoliosis angle, kyphosis angle, S-DAR, T-DAR, and kyphosis correction rate than the non-NC group. The results showed that the NC group tended to undergo high-grade osteotomy. No significant differences were observed in shortening distance or anterior column support of the osteotomy area between the two groups. CONCLUSIONS: Postoperative neurological complications were closely related to preoperative age, etiology, severity of deformity, angulation rate, spinal cord function classification, intraoperative osteotomy site, osteotomy type, and kyphosis correction rate. Identification of these risk factors and relative development of surgical techniques will help to minimize neural injuries and manage postoperative neurological complications.


Asunto(s)
Osteotomía/efectos adversos , Complicaciones Posoperatorias/etiología , Curvaturas de la Columna Vertebral/cirugía , Traumatismos del Sistema Nervioso/epidemiología , Traumatismos del Sistema Nervioso/etiología , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteotomía/métodos , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento
16.
Med Sci Monit ; 26: e925371, 2020 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-32794474

RESUMEN

BACKGROUND This study aimed to evaluate the effects of different combined evoked potentials monitoring modes for non-osteotomy and osteotomy surgery of spinal deformity, and to select individualized modes for various surgeries. MATERIAL AND METHODS We retrospectively reviewed a total of 188 consecutive cases undergoing spinal deformity correction. All patients were classified into 2 cohorts: non-osteotomy (Group A) and osteotomy (Group B). According to intraoperative evoked potential monitoring mode, Group A was divided into 2 sub-groups: A1 [spinal somatosensory evoked potential (SSEP)/motor evoked potential (MEP), n=67)] and A2 [SSEP/MEP/descending neurogenic evoked potential (DNEP), n=52]. Group B was classified as B1 (SSEP/MEP, n=27) and B2 (SSEP/MEP/DNEP, n=42). The demographics, surgical parameters, and evoked potential events of different combined monitoring modes were analyzed within each group. RESULTS The baselines of SSEP/MEP/DNEP in all cases were elicited successfully. Three cases with evoked potential (EP) events (2 with MEP changes and 1 with SSEP/MEP change) were noted in Group A1 and 1 with SSEP change in Group A2, with no neurological complications. Thirteen cases in Group B1 were positive for MEP intraoperatively, including 16 EP events (13 with MEP change and 3 with both SSEP+MEP changes), with no neural complications. In Group B2, 15 cases had 21 EP events, including 12 with MEP change and 2 with SSEP+MEP changes, with no complications. Postoperative neurological complications were observed in 5 of the 7 cases with SS4EP/DNEP changes. CONCLUSIONS Intraoperative simultaneous SSEP/MEP can effectively reflect neurological function in non-osteotomy spinal surgery patients. Simultaneous SSEP/MEP/DNEP can effectively avoid the unnecessary interference by false-positive results of MEP during osteotomy.


Asunto(s)
Potenciales Evocados Somatosensoriales , Monitoreo Fisiológico/métodos , Osteotomía/métodos , Enfermedades de la Columna Vertebral/cirugía , Adolescente , Adulto , Niño , Femenino , Humanos , Cuidados Intraoperatorios , Masculino , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
17.
Nat Mater ; 17(11): 1005-1012, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30353088

RESUMEN

Graphene and other two-dimensional materials possess desirable mechanical, electrical and chemical properties for incorporation into or onto colloidal particles, potentially granting them unique electronic functions. However, this application has not yet been realized, because conventional top-down lithography scales poorly for producing colloidal solutions. Here, we develop an 'autoperforation' technique that provides a means of spontaneous assembly for surfaces composed of two-dimensional molecular scaffolds. Chemical vapour deposited two-dimensional sheets can autoperforate into circular envelopes when sandwiching a microprinted polymer composite disk of nanoparticle ink, allowing liftoff into solution and simultaneous assembly. The resulting colloidal microparticles have two independently addressable, external Janus faces that we show can function as an intraparticle array of vertically aligned, two-terminal electronic devices. Such particles demonstrate remarkable chemical and mechanical stability and form the basis of particulate electronic devices capable of collecting and storing information about their surroundings, extending nanoelectronics into previously inaccessible environments.

18.
Molecules ; 24(3)2019 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-30704049

RESUMEN

In this study, an immobilization strategy for magnetic cross-linking enzyme aggregates of lipase B from Candida antarctica (CALB) was developed and investigated. Magnetic particles were prepared by conventional co-precipitation. The magnetic nanoparticles were modified with 3-aminopropyltriethoxysilane (APTES) to obtain surface amino-functionalized magnetic nanoparticles (APTES⁻Fe3O4) as immobilization materials. Glutaraldehyde was used as a crosslinker to covalently bind CALB to APTES⁻Fe3O4. The optimal conditions of immobilization of lipase and resolution of racemic 1-phenylethanol were investigated. Under optimal conditions, esters could be obtained with conversion of 50%, enantiomeric excess of product (eep) > 99%, enantiomeric excess of substrate (ees) > 99%, and enantiomeric ratio (E) > 1000. The magnetic CALB CLEAs were successfully used for enzymatic kinetic resolution of fifteen secondary alcohols. Compared with Novozym 435, the magnetic CALB CLEAs exhibited a better enantioselectivity for most substrates. The conversion was still greater than 49% after the magnetic CALB CLEAs had been reused 10 times in a 48 h reaction cycle; both ees and eep were close to 99%. Furthermore, there was little decrease in catalytic activity and enantioselectivity after being stored at -20 °C for 90 days.


Asunto(s)
Alcoholes/química , Enzimas Inmovilizadas , Proteínas Fúngicas/química , Lipasa/química , Nanopartículas de Magnetita , Biocatálisis , Activación Enzimática , Estabilidad de Enzimas , Glutaral , Cinética , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/ultraestructura , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Factores de Tiempo
19.
Angew Chem Int Ed Engl ; 57(1): 172-176, 2018 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-29178355

RESUMEN

The oxygen evolution reaction (OER) is involved in various renewable energy systems, such as water-splitting cells and metal-air batteries. Ni-Fe layered double hydroxides (LDHs) have been reported as promising OER electrocatalysts in alkaline electrolytes. The rational design of advanced nanostructures for Ni-Fe LDHs is highly desirable to optimize their electrocatalytic performance. Herein, we report a facile self-templated strategy for the synthesis of novel hierarchical hollow nanoprisms composed of ultrathin Ni-Fe LDH nanosheets. Tetragonal nanoprisms of nickel precursors were first synthesized as the self-sacrificing template. Afterwards, these Ni precursors were consumed during the hydrolysis of iron(II) sulfate for the simultaneous growth of a layer of Ni-Fe LDH nanosheets on the surface. The resultant Ni-Fe LDH hollow prisms with large surface areas manifest high electrocatalytic activity towards the OER with low overpotential, small Tafel slope, and remarkable stability.

20.
Biochim Biophys Acta Mol Basis Dis ; 1863(7): 1848-1857, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28483578

RESUMEN

Hepatic stellate cells (HSCs) are considered as the main effector cells in vitamin A metabolism and liver fibrosis, as well as in hepatic immune regulation. Recently, researches have revealed that HSCs have plasticity and heterogeneity, which depend on their lobular location and whether liver is normal or injured. This research aimed to explore the biological characteristics and heterogeneity of HSCs in mice with Schistosoma japonicum (S. japonicum) infection, and determine the subpopulation of HSCs in pathogenesis of hepatic fibrosis caused by S. japonicum infection. Results revealed that HSCs significantly increased the expressions of MHC II and fibrogenic genes after S. japonicum infection, and could be classified into MHC II+ HSCs and MHC II- HSCs subsets. Both two HSCs populations suppressed the proliferation of activated CD4+T cells, whereas only MHC II- HSCs displayed a myofibroblast-like phenotype. In response to IFN-γ, HSCs up-regulated the expressions of MHC II and CIITA, while down-regulated the expression of fibrogenic gene Col1. In addition, praziquantel treatment decreased the expressions of fibrogenic genes in MHC II- HSCs. These results confirmed that HSCs from S. japonicum-infected mice have heterogeneity. The MHC II- α-SMA+ HSCs were major subsets of HSCs contributing to liver fibrosis and could be considered as a potential target of praziquantel anti-fibrosis treatment.


Asunto(s)
Células Estrelladas Hepáticas/inmunología , Antígenos de Histocompatibilidad Clase II/inmunología , Cirrosis Hepática/inmunología , Schistosoma japonicum/inmunología , Esquistosomiasis Japónica/inmunología , Animales , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/patología , Femenino , Células Estrelladas Hepáticas/patología , Antígenos de Histocompatibilidad Clase II/genética , Interferón gamma/genética , Interferón gamma/inmunología , Cirrosis Hepática/genética , Cirrosis Hepática/patología , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Esquistosomiasis Japónica/genética , Esquistosomiasis Japónica/patología
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