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2.
Nat Immunol ; 20(8): 992-1003, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31263279

RESUMO

Here we identify a group 2 innate lymphoid cell (ILC2) subpopulation that can convert into interleukin-17 (IL-17)-producing NKp44- ILC3-like cells. c-Kit and CCR6 define this ILC2 subpopulation that exhibits ILC3 features, including RORγt, enabling the conversion into IL-17-producing cells in response to IL-1ß and IL-23. We also report a role for transforming growth factor-ß in promoting the conversion of c-Kit- ILC2s into RORγt-expressing cells by inducing the upregulation of IL23R, CCR6 and KIT messenger RNA in these cells. This switch was dependent on RORγt and the downregulation of GATA-3. IL-4 was able to reverse this event, supporting a role for this cytokine in maintaining ILC2 identity. Notably, this plasticity has physiological relevance because a subset of RORγt+ ILC2s express the skin-homing receptor CCR10, and the frequencies of IL-17-producing ILC3s are increased at the expense of ILC2s within the lesional skin of patients with psoriasis.


Assuntos
Interleucina-17/imunologia , Linfócitos/imunologia , Psoríase/patologia , Pele/patologia , Células Cultivadas , Humanos , Interleucina-1beta/imunologia , Subunidade p19 da Interleucina-23/imunologia , Interleucina-4/imunologia , Linfócitos/citologia , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Proteínas Proto-Oncogênicas c-kit/metabolismo , Psoríase/imunologia , Receptores CCR10/metabolismo , Pele/imunologia , Fator de Crescimento Transformador beta/metabolismo
3.
Metab Brain Dis ; 39(4): 625-633, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38416338

RESUMO

Selenium-containing agents showed novel anticancer activity by triggering pro-oxidative mechanism. Studies confirmed that methylseleninic acid (MeSe) displayed broad-spectrum anti-tumor activity against kinds of human cancers. However, the anticancer effects and mechanism of MeSe against human glioma growth have not been explored yet. Herein, the present study showed that MeSeA dose-dependently inhibited U251 and U87 human glioma cells growth in vitro. Flow cytometry analysis indicated that MeSe induced significant U251 cells apoptosis with a dose-dependent manner, followed by the activation of caspase-7, caspase-9 and caspase-3. Immunofluorescence staining revealed that MeSe time-dependently caused reactive oxide species (ROS) accumulation and subsequently resulted in oxidative damage, as convinced by the increased phosphorylation level of Ser428-ATR, Ser1981-ATM, Ser15-p53 and Ser139-histone. ROS inhibition by glutathione (GSH) effectively attenuated MeSe-induced ROS generation, oxidative damage, caspase-3 activation and cytotoxicity, indicating that ROS was an upstream factor involved in MeSe-mediated anticancer mechanism in glioma. Importantly, MeSe administration in nude mice significantly inhibited glioma growth in vivo by inducing apoptosis through triggering oxidative damage. Taken together, our findings validated the possibility that MeSe as a selenium-containing can act as potential tumor chemotherapy agent for therapy of human glioma.


Assuntos
Apoptose , Glioma , Camundongos Nus , Compostos Organosselênicos , Estresse Oxidativo , Espécies Reativas de Oxigênio , Humanos , Glioma/tratamento farmacológico , Glioma/metabolismo , Glioma/patologia , Apoptose/efeitos dos fármacos , Compostos Organosselênicos/farmacologia , Compostos Organosselênicos/uso terapêutico , Animais , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular Tumoral , Estresse Oxidativo/efeitos dos fármacos , Camundongos , Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Proliferação de Células/efeitos dos fármacos , Camundongos Endogâmicos BALB C
4.
BMC Musculoskelet Disord ; 25(1): 129, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38347518

RESUMO

OBJECTIVE: To study the biomechanical characteristics of each tissue structure when using different 3D printing Cage in osteoporotic patients undergoing interbody fusion. METHODS: A finite element model of the lumbar spine was reconstructed and validated with regarding a range of motion and intervertebral disc pressure from previous in vitro studies. Cage and pedicle screws were implanted and part of the lamina, spinous process, and facet joints were removed in the L4/5 segment of the validated mode to simulate interbody fusion. A 280 N follower load and 7.5 N·m moment were applied to different postoperative models and intact osteoporotic model to simulate lumbar motion. The biomechanical characteristics of different models were evaluated by calculating and analyzing the range of motion of the fixed and cephalic adjacent segment, the stress of the screw-rod system, the stress at the interface between cage and L5 endplate, and intervertebral disc pressure of the adjacent segment. RESULTS: After rigid fixation, the range of motion of the fixed segment of model A-C decreased significantly, which was much smaller than that of the osteoporotic model. And with the increase of the axial area of the interbody fusion cages, the fixed segment of model A-C tended to be more stable. The range of motion and intradiscal pressure of the spinal models with different interbody fusion cages were higher than those of the complete osteoporosis model, but there was no significant difference between the postoperative models. On the other hand, the L5 upper endplate stress and screw-rod system stress of model A-C show a decreasing trend in different directions of motion. The stress of the endplate is the highest during flexion, which can reach 40.5 MPa (model A). The difference in endplate stress between models A-C was the largest during lateral bending. The endplate stress of models A and B was 150.5% and 140.9% of that of model C, respectively. The stress of the screw-rod system was the highest during lateral bending (model A, 102.0 MPa), which was 108.4%, 102.4%, 110.4%, 114.2% of model B and 158.5%, 110.1%, 115.8%, 125.4% of model C in flexion, extension, lateral bending, and rotation, respectively. CONCLUSIONS: For people with osteoporosis, no matter what type of cage is used, good immediate stability can be achieved after surgery. Larger cage sizes provide better fixation without significantly increasing ROM and IDP in adjacent segments, which may contribute to the development of ASD. In addition, larger cage sizes can disperse endplate stress and reduce stress concentration, which is of positive significance in preventing cage subsidence after operation. The cage and screw rod system establish a stress conduction pathway on the spine, and a larger cage greatly enhances the stress-bearing capacity of the front column, which can better distribute the stress of the posterior spine structure and the stress borne by the posterior screw rod system, reduce the stress concentration phenomenon of the nail rod system, and avoid exceeding the yield strength of the material, resulting in the risk of future instrument failure.


Assuntos
Osteoporose , Parafusos Pediculares , Fusão Vertebral , Humanos , Análise de Elementos Finitos , Fusão Vertebral/métodos , Fenômenos Biomecânicos , Amplitude de Movimento Articular , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Osteoporose/cirurgia
5.
BMC Musculoskelet Disord ; 25(1): 717, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39243084

RESUMO

BACKGROUND: Current research lacks comprehensive investigation into the biomechanical changes in the spinal cord and nerve roots during scoliosis correction. This study employs finite element analysis to extensively explore these biomechanical variations across different Cobb angles, providing valuable insights for clinical treatment. METHODS: A personalized finite element model, incorporating vertebrae, ligaments, spinal cord, and nerve roots, was constructed using engineering software. Forces and displacements were applied to achieve Cobb angle improvements, designating T1/2-T4/5 as the upper segment, T5/6-T8/9 as the middle segment, and T9/10-L1/2 as the lower segment. Simulations under traction, pushing, and traction + torsion conditions were conducted, and biomechanical changes in each spinal cord segment and nerve roots were analyzed. RESULTS: Throughout the scoliosis correction process, the middle spinal cord segment consistently exhibited a risk of injury under various conditions and displacements. The lower spinal cord segment showed no significant injury changes under traction + torsion conditions. In the early correction phase, the upper spinal cord segment demonstrated a risk of injury under all conditions, and the lower spinal cord segment presented a risk of injury under pushing conditions. Traction conditions posed a risk of nerve injury on both sides in the middle and lower segments. Under pushing conditions, there was a risk of nerve injury on both sides in all segments. Traction + torsion conditions implicated a risk of injury to the right nerves in the upper segment, both sides in the middle segment, and the left side in the lower segment. In the later correction stage, there was a risk of injury to the upper spinal cord segment under traction + torsion conditions, the left nerves in the middle segment under traction conditions, and the right nerves in the upper segment under pushing conditions. CONCLUSION: When the correction rate reaches 61-68%, particular attention should be given to the upper-mid spinal cord. Pushing conditions also warrant attention to the lower spinal cord and the nerve roots on both sides of the main thoracic curve. Traction conditions require attention to nerve roots bilaterally in the middle and lower segments, while traction combined with torsion conditions necessitate focus on the right-side nerve roots in the upper segment, both sides in the middle segment, and the left-side nerve roots in the lower segment.


Assuntos
Análise de Elementos Finitos , Escoliose , Medula Espinal , Raízes Nervosas Espinhais , Tração , Humanos , Escoliose/fisiopatologia , Raízes Nervosas Espinhais/fisiopatologia , Fenômenos Biomecânicos/fisiologia , Medula Espinal/fisiopatologia , Tração/métodos , Vértebras Torácicas , Vértebras Lombares , Adolescente
6.
Proc Natl Acad Sci U S A ; 118(20)2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-33986115

RESUMO

Whole-genome duplication (WGD) plays important roles in plant evolution and function, yet little is known about how WGD underlies metabolic diversification of natural products that bear significant medicinal properties, especially in nonmodel trees. Here, we reveal how WGD laid the foundation for co-option and differentiation of medicinally important ursane triterpene pathway duplicates, generating distinct chemotypes between species and between developmental stages in the apple tribe. After generating chromosome-level assemblies of a widely cultivated loquat variety and Gillenia trifoliata, we define differentially evolved, duplicated gene pathways and date the WGD in the apple tribe at 13.5 to 27.1 Mya, much more recent than previously thought. We then functionally characterize contrasting metabolic pathways responsible for major triterpene biosynthesis in G. trifoliata and loquat, which pre- and postdate the Maleae WGD, respectively. Our work mechanistically details the metabolic diversity that arose post-WGD and provides insights into the genomic basis of medicinal properties of loquat, which has been used in both traditional and modern medicines.


Assuntos
Eriobotrya/genética , Duplicação Gênica , Poliploidia , Triterpenos/metabolismo , Vias Biossintéticas , Eriobotrya/metabolismo , Genoma de Planta
7.
Ecotoxicol Environ Saf ; 283: 116975, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39216222

RESUMO

The contribution of plant hormones and energy-rich compounds and their metabolites (ECMs) in alleviating aluminum (Al) toxicity by elevated pH remains to be clarified. For the first time, a targeted metabolome was applied to identify Al-pH-interaction-responsive hormones and ECMs in Citrus sinensis leaves. More Al-toxicity-responsive hormones and ECMs were identified at pH 4.0 [4 (10) upregulated and 7 (17) downregulated hormones (ECMs)] than those at pH 3.0 [1 (9) upregulated and 4 (14) downregulated hormones (ECMs)], suggesting that the elevated pH improved the adaptation of hormones and ECMs to Al toxicity in leaves. The roles of hormones and ECMs in reducing leaf Al toxicity mediated by elevated pH might include the following aspects: (a) improved leaf growth by upregulating the levels of jasmonoyl-L-isoleucine (JA-ILE), 6-benzyladenosine (BAPR), N6-isopentenyladenosine (IPR), cis-zeatin-O-glucoside riboside (cZROG), and auxins (AUXs), preventing Al toxicity-induced reduction of gibberellin (GA) biosynthesis, and avoiding jasmonic acid (JA)-mediated defense; (b) enhanced biosynthesis and accumulation of tryptophan (TRP), as well as the resulting increase in biosynthesis of auxin, melatonin and secondary metabolites (SMs); (c) improved ability to maintain the homeostasis of ATP and other phosphorus (P)-containing ECMs; and (d) enhanced internal detoxification of Al due to increased organic acid (OA) and SM accumulation and elevated ability to detoxify reactive oxygen species (ROS) due to enhanced SM accumulation. To conclude, the current results corroborate the hypotheses that elevated pH reduces Al toxicity by upregulating the ability to maintain the homeostasis of ATP and other P-containing ECMs in leaves under Al toxicity and (b) hormones participate in the elevated pH-mediated alleviation of Al toxicity by positively regulating growth, the ability to detoxify ROS, and the internal detoxification of Al in leaves under Al toxicity. Our findings provide novel insights into the roles of hormones and ECMs in mitigating Al toxicity mediated by the elevated pH.


Assuntos
Alumínio , Citrus sinensis , Reguladores de Crescimento de Plantas , Folhas de Planta , Folhas de Planta/efeitos dos fármacos , Alumínio/toxicidade , Citrus sinensis/efeitos dos fármacos , Concentração de Íons de Hidrogênio
8.
BMC Musculoskelet Disord ; 24(1): 695, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37649054

RESUMO

OBJECTIVE: This study aimed to compare the biomechanical properties of lumbar interbody fusion involving two types of cages. The study evaluated the effectiveness of the cage spanning the ring apophysis, regardless of the endplate's integrity. METHODS: A finite element model of the normal spine was established and validated in this study. The validated model was then utilized to simulate Lateral Lumbar Interbody Fusion (LLIF) with posterior pedicle screw fixation without posterior osteotomy. Two models of interbody fusion cage were placed at the L4/5 level, and the destruction of the bony endplate caused by curetting the cartilaginous endplate during surgery was simulated. Four models were established, including Model 1 with an intact endplate and long cage spanning the ring apophysis, Model 2 with endplate decortication and long cage spanning the ring apophysis, Model 3 with an intact endplate and short cage, and Model 4 with endplate decortication and short cage. Analyzed were the ROM of the fixed and adjacent segments, screw rod system stress, interface stress between cage and L5 endplate, trabecular bone stress on the upper surface of L5, and intervertebral disc pressure (IDP) of adjacent segments. RESULTS: There were no significant differences in ROM and IDP between adjacent segments in each postoperative model. In the short cage model, the range of motion (ROM), contact pressure between the cage and endplate, stress in L5 cancellous bone, and stress in the screw-rod system all exhibited an increase ranging from 0.4% to 79.9%, 252.9% to 526.9%, 27.3% to 133.3%, and 11.4% to 107%, respectively. This trend was further amplified when the endplate was damaged, resulting in a maximum increase of 88.6%, 676.1%, 516.6%, and 109.3%, respectively. Regardless of the integrity of the endplate, the long cage provided greater support strength compared to the short cage. CONCLUSIONS: Caution should be exercised during endplate preparation and cage placement to maintain the endplate's integrity. Based on preoperative X-ray evaluation, the selection of a cage that exceeds the width of the pedicle by at least 5 mm (ensuring complete coverage of the vertebral ring) has demonstrated remarkable biomechanical performance in lateral lumbar interbody fusion procedures. By opting for such a cage, we expect a reduced occurrence of complications, including cage subsidence, internal fixation system failure, and rod fracture.


Assuntos
Fraturas Ósseas , Parafusos Pediculares , Humanos , Análise de Elementos Finitos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Osso Esponjoso
9.
BMC Musculoskelet Disord ; 24(1): 85, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36726086

RESUMO

OBJECTIVE: To study the biomechanical characteristics of various tissue structures of different sizes of 3D printed Cage in lumbar interbody fusion. METHODS: A finite element model of normal spine was reconstructed and verified. Pedicle screws and Cage of different sizes were implanted in the L4/5 segment to simulate lumbar interbody fusion. The range of motion of the fixed and cephalic adjacent segment, the stress of the screw-rod system, the stress at the interface between cage and L5 endplate, and intervertebral disc pressure of the adjacent segment were calculated and analyzed. RESULTS: The range of motion and intervertebral disc pressure of the adjacent segment of each postoperative model were larger than those of the intact model, but there was not much difference between them. The stress of cage-endplate interface was also larger than that of the intact model. However, the difference is that the stress of the endplate and the screw-rod system has a tendency to decrease with the increase of the axial area of cage. CONCLUSIONS: Cage with larger axial area in lumbar interbody fusion can reduce the stress of internal fixation system and endplate, but will not increase the range of motion and intervertebral disc pressure of adjacent segment. It has a certain effect in preventing the cage subsidence, internal fixation system failure and screw rod fracture.


Assuntos
Parafusos Pediculares , Fusão Vertebral , Humanos , Análise de Elementos Finitos , Fenômenos Biomecânicos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Amplitude de Movimento Articular , Impressão Tridimensional
10.
J Environ Manage ; 335: 117514, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36841000

RESUMO

Ecological restoration is an important approach to improving landscape sustainability. However, ecological restoration in drylands is strongly limited by water resources. Therefore, a technical route for ecological restoration in drylands that creates sustainable landscapes based on those water constraints is needed. In this study, we develop a spatially explicit framework named "Constraint-Pattern-Benefit" to plan ecological restoration patterns in Inner Mongolia, China. Based on a prediction of the ecosystem service (ES) increase under limited evapotranspiration as a water constraint, we constructed 5 landscape sustainability-related strategies with 100 ecological restoration scenarios, which considered fragmentation of restoration locations, distance to city, water consumption, and the allocation scale to determine the spatial arrangement of ecological restoration. Results show that the ES increase potential of ecological restoration under water constraints is distributed in the center of Inner Mongolia. The multi-objective scenario simultaneously achieves 59.1% water yield, 74.2% soil conservation, 57.2% sand fixation, and 52.8% carbon sequestration with 50% restored landscape. Considering the indicators of fragmentation, water consumption, and distance to city decreases the restored landscape fragmentation from 0.44 to 0.26, improves the restoration efficiency by 14.41%, and increases the beneficiary population by 35.5%, respectively. Small-scale allocation can further increase the ES realization efficiency, which is on average 4.8% higher at the city scale than at the provincial scale. Moreover, this approach focuses on the sustainable effect of the spatial arrangement on dryland landscapes at different scales, which provides methodological support for improving the sustainability of drylands.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Água , China , Solo
11.
Cell Mol Biol (Noisy-le-grand) ; 67(6): 281-290, 2022 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-35818185

RESUMO

Polyphenols and flavonoids are phytochemicals that have essential roles in human nutrition. In this regard, the contents of polyphenols and flavonoids in Houttuynia cordata Thunb and their antioxidant activities were evaluated in the current study. Two Houttuynia cordata materials with the same chromosome number and chemical type were used to comprehensively assess the contents of total phenols and flavonoids in different parts of H. cordata. These chemical components were extracted by the ultrasonic method. The results showed that the total phenols and antioxidant capacity of different parts of H. cordata were significantly different. The content of polyphenols in roots and stems was low, the antioxidant capacity was weak, the total phenols in flowers and leaves were high, and the antioxidant capacity was strong. Therefore, different parts of H. cordata had different pharmacological and food effects. The whole herb can be used as Chinese herbal medicine, and its young leaves and roots can be used as vegetables. Flavonoids are the main phenolic components, and total phenols are the main components of antioxidant activity. It can explain a very significant positive correlation between total phenols and flavonoids. Therefore, in the further breeding work of H. cordata, the procedure can be simplified by determining one of the above indexes to predict the varieties with high total phenolic and antioxidant activity.


Assuntos
Houttuynia , Antioxidantes/farmacologia , Flavonoides/farmacologia , Houttuynia/química , Humanos , Fenóis/farmacologia , Polifenóis , Ultrassom
12.
BMC Musculoskelet Disord ; 23(1): 1122, 2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36550443

RESUMO

BACKGROUND: At present, research on spinal shortening is mainly focused on the safe distance of spinal shortening and the mechanism of spinal cord injury, but there is no research on the biomechanical characteristics of different shortening distances. The purpose of this study was to study the biomechanical characteristics of spine and internal fixation instruments at different shortening distances by the finite element (FE) method. METHODS: An FE model of lumbar L1-S was established and referred to the previous in vitro experiments to verify the rationality of the model by verifying the Intradiscal pressure (IDP) and the range of motion (ROM) of the motion segment. Five element models of spinal shortening were designed under the safe distance of spinal shortening, and the entire L3 vertebra and both the upper and lower intervertebral discs were resected. Model A was not shortened, while models B-E were shortened by 10%, 20%, 30% and 50% of the vertebral body, respectively. Constraining the ROM of the sacrum in all directions, a 7.5 N ·m moment and 280 N follower load were applied on the L1 vertebra to simulate the motion of the lumbar vertebrae in three planes. The ROM of the operated segments, the Von Mises stress (VMS) of the screw-rod system, the VMS of the upper endplate at the interface between the titanium cage and the L4 vertebral body, and the ROM and the IDP of the adjacent segment (L5/S) were recorded and analysed. RESULTS: All surgical models showed good stability at the operated segments (L1-5), with the greatest constraint in posterior extension (99.3-99.7%), followed by left-right bending (97.9-98.7%), and the least constraint in left-right rotation (84.9-86.3%) compared with the intact model. The VMS of the screw-rod system and the ROM and IDP of the distal adjacent segments of models A-E showed an increasing trend, in which the VMS of the screw-rod system of model E was the highest under flexion (172.5 MPa). The VMS of the endplate at the interface between the cage and L4 upper endplate of models A-E decreased gradually, and these trend were the most obvious in flexion, which were 3.03, 2.95, 2.83, 2.78, and 2.61 times that of the intact model, respectively. CONCLUSION: When performing total vertebrae resection and correcting the spinal deformity, if the corrected spine has met our needs, the distance of spinal shortening should be minimized to prevent spinal cord injury, fracture of internal fixations and adjacent segment disease (ASD).


Assuntos
Parafusos Pediculares , Fusão Vertebral , Humanos , Análise de Elementos Finitos , Fusão Vertebral/métodos , Fenômenos Biomecânicos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Parafusos Ósseos , Amplitude de Movimento Articular
13.
BMC Musculoskelet Disord ; 23(1): 851, 2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36076212

RESUMO

OBJECTIVE: To investigate and evaluate the biomechanical behaviour of tension-band-reconstruction (TBR) and ordinary titanium plates in open-door laminoplasty by finite element (FE) analysis. METHODS: TBR titanium plate and ordinary titanium plate were implanted into a validated finite element model of healthy adult cervical vertebrae. Among them, 5 ordinary titanium plate were used in model A, 2 TBR titanium plates and 3 ordinary titanium plates were used in model B, and 5 TBR titanium plates were used in model C. The same loading conditions was applied identically to all models. Range of motion (ROM) of the vertebral body, stress distribution of the titanium plate and intradiscal pressure (IDP) were compared in flexion, extension, lateral bending and rotation. RESULTS: The ROM of model B and C was similar in flexion and extension, and both were smaller than that of model A. The highest von Mises stress in the titanium plate appears is in model C. The IDP in C2/3 was significantly higher than that in other segments in flexion. There was no significant difference in IDP among three models in left lateral bending and left axial rotation. CONCLUSION: Application of TBR titanium plate in open-door laminoplasty can reduced ROM in flexion, extension and axial rotation of the cervical vertebrae. But the increase of stress in TBR titanium plate could lead to higher risk of adverse events such as titanium plate deformation. Moreover, compared with complete TBR titanium plate, the combination of TBR titanium plate for C3 and C7 with ordinary titanium plate for the other vertebrae largely reduce the stress of the titanium plates by ensuring stability. The proposed FE model (C2-T1) exhibits a great potential in evaluating biomechanical behaviour of TBR titanium plate for open-door laminoplasty.


Assuntos
Laminoplastia , Adulto , Humanos , Fenômenos Biomecânicos , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Análise de Elementos Finitos , Laminoplastia/efeitos adversos , Amplitude de Movimento Articular , Titânio
14.
Ecotoxicol Environ Saf ; 156: 294-300, 2018 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-29571107

RESUMO

This work reports the preparation and adsorption of Ni(II) via activated carbons which produced from hide waste (HWAC) and high-pressure steaming hide waste (HWSAC) with potassium silicate as the activating agent. The best preparation condition for HWAC and HWSAC was the activation temperature of 700 °C using an impregnation ratio of 2:1. Both of them were characterized by N2 adsorption/desorption isotherms, SEM and FT-IR spectra. The surface area of HWAC and HWSAC was 1804.37 and 1361.26 m2/g, respectively. Despite the surface area of HWAC being larger than that of HWSAC, but the adsorption capacity of Ni(II) for HWAC was lower than that for HWSAC. Furthermore, the adsorption capacity of Ni(II) for both HWAC and HWSAC showed pH-dependent behavior and increased with the increase in pH value, which can be attributed to the functional groups of HWAC and HWSAC materials through the electrostatic attraction. The adsorption data for HWAC and HWSAC were fitted with four isotherm models (Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich) and four kinetic models (pseudo-first order model, pseudo-second order model, intra-particle diffusion and Elovich equation), indicating that Langmuir isotherm and Pseudo-second order model fitted well with high coefficient of determination (R2 > 0.99) for both the two adsorbents. The positive enthalpy of adsorption (ΔH) and free energy of adsorption (ΔG) indicate a spontaneous and endothermic nature of the process. These results demonstrated that activated carbon can be prepared from hide waste which could remove heavy metal such as Ni(II) effectively.


Assuntos
Carvão Vegetal/química , Níquel/química , Curtume , Gerenciamento de Resíduos , Adsorção , Temperatura Alta , Concentração de Íons de Hidrogênio , Modelos Teóricos , Nitrogênio/química , Pressão , Silicatos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Poluentes Químicos da Água/química
15.
Neurobiol Learn Mem ; 130: 105-17, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26872592

RESUMO

Impairment of learning and memory has been documented in the later life of offspring to maternal consumption with high energy diet. Environmental stimulation enhances the ability of learning and memory. However, potential effects of environmental stimulation on the programming-associated deficit of learning and memory have not been addressed. Here, we examined the effects of enriched-housing on hippocampal learning and memory in adult female offspring rats from mother fed with 60% high fructose diet (HFD) during pregnancy and lactation. Impairment of spatial learning and memory performance in HFD group was observed in offspring at 3-month-old. Hippocampal brain-derived neurotrophic factor (BDNF) was decreased in the offspring. Moreover, the HFD group showed an up-regulation of histone deacetylase 4 (HDAC4) in the nuclear fractions of hippocampal neurons. Stimulation to the offspring for 4weeks after winning with an enriched-housing environment effectively rescued the decrease in cognitive function and hippocampal BDNF level; alongside a reversal of the increased distribution of nuclear HDAC4. Together these results suggest that later life environmental stimulation effectively rescues the impairment of hippocampal learning and memory in female offspring to maternal HFD intake through redistributing nuclear HDAC4 to increase BDNF expression.


Assuntos
Meio Ambiente , Frutose/administração & dosagem , Histona Desacetilases/metabolismo , Aprendizagem/efeitos dos fármacos , Memória/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Cognição/efeitos dos fármacos , Feminino , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Gravidez , Ratos , Ratos Sprague-Dawley , Aprendizagem Espacial/efeitos dos fármacos
16.
PLoS Comput Biol ; 9(7): e1003140, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23874182

RESUMO

Nanog is a principal pluripotency regulator exhibiting a disperse distribution within stem cell populations in vivo and in vitro. Increasing evidence points to a functional role of Nanog heterogeneity on stem cell fate decisions. Allelic control of Nanog gene expression was reported recently in mouse embryonic stem cells. To better understand how this mode of regulation influences the observed heterogeneity of NANOG in stem cell populations, we assembled a multiscale stochastic population balance equation framework. In addition to allelic control, gene expression noise and random partitioning at cell division were considered. As a result of allelic Nanog expression, the distribution of Nanog exhibited three distinct states but when combined with transcriptional noise the profile became bimodal. Regardless of their allelic expression pattern, initially uniform populations of stem cells gave rise to the same Nanog heterogeneity within ten cell cycles. Depletion of NANOG content in cells switching off both gene alleles was slower than the accumulation of intracellular NANOG after cells turned on at least one of their Nanog gene copies pointing to Nanog state-dependent dynamics. Allelic transcription of Nanog also raises issues regarding the use of stem cell lines with reporter genes knocked in a single allelic locus. Indeed, significant divergence was observed in the reporter and native protein profiles depending on the difference in their half-lives and insertion of the reporter gene in one or both alleles. In stem cell populations with restricted Nanog expression, allelic regulation facilitates the maintenance of fractions of self-renewing cells with sufficient Nanog content to prevent aberrant loss of pluripotency. Our findings underline the role of allelic control of Nanog expression as a prime determinant of stem cell population heterogeneity and warrant further investigation in the contexts of stem cell specification and cell reprogramming.


Assuntos
Alelos , Células-Tronco Embrionárias/citologia , Proteínas de Homeodomínio/genética , Animais , Expressão Gênica , Camundongos , Proteína Homeobox Nanog
17.
Ambio ; 53(9): 1355-1366, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38564103

RESUMO

When accounting for the social-ecological impact of an ecological restoration program, both objective environmental contexts and people's subjective perceptions are required. While this kind of environmental impact assessment lacks a comprehensive perspective. We use the difference-in-differences model to evaluate the effect of the greenness of the landscape after ecological migration in the Qilian Mountains in China; and analysis of variance and fixed effects models are used to evaluate the effects of such ecological restoration programs on local people's perceptions. The results show that the ecological migration program in the Qilian Mountains has been successful at not only significantly improving remotely sensed greenness at the landscape scale, but also at enhancing immigrants' environmental perceptions. These findings demonstrate the environmental impacts of ecological migration from a social-ecological perspective, and can provide methodological implications for landscape planning to support a better understanding of ecological restoration programs in the drylands.


Assuntos
Conservação dos Recursos Naturais , China , Humanos , Ecossistema , Meio Ambiente , Ecologia
18.
Int J Surg ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38990309

RESUMO

BACKGROUND: Autophagy is intimately associated with the development of cardiomyopathy, and has received widespread attention in recent years. However, no relevant bibliometric analysis is reported at present. In order to summarize the research status of autophagy in cardiomyopathy and provide direction for future research, we conducted a comprehensive, detailed, and multidimensional bibliometric analysis of the literature published in this field from 2004 to 2023. METHODS: All literatures related autophagy in cardiomyopathy from 2004 to 2023 were collected from the Web of Science Core Collection (WOSCC), and annual papers, global publication trends and proportion charts were analyzed and plotted using Graphpad price v8.0.2. In addition, CtieSpace (6.2.4R (64 bit) Advanced Edition) and VOSviewer (1.6.18 Edition) were used to analyze and visualize these data. RESULTS: 2279 papers about autophagy in cardiomyopathy were accessed in the WoSCC over the last 20 years, comprising literatures from 70 countries and regions, 2208 institutions, and 10,810 authors. China contributes 56.32% of the total publications, substantially surpassing other countries, while the U.S. is ranked first in frequency of citations. Among the top 10 authors, 6 are from China and 4 are from the United States. Air Force Military Medical University was the institution with the highest number of publications; while journal of molecular and cellular cardiology (62 articles, 2.71% of the total) was the journal with the highest number of papers published in the field. Clustering of co-cited references and temporal clustering analysis showed that ferroptosis, hydrogen sulfide mitophagy, lipid peroxidation, oxidative stress, and SIRT-1 are hot topics and trends in the field. The principal keywords are oxidative stress, heart and heart-failure. CONCLUSION: The research on autophagy in cardiomyopathy is in the developmental stage. This represents the first bibliometric analysis of autophagy in cardiomyopathy , revealing the current research hotspots and future research directions in this field.

19.
Sci Rep ; 14(1): 18816, 2024 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-39138300

RESUMO

The chloroplast genomes of wild loquat can help to determine their place in the history of evolution. Here, we sequenced and assembled two novel wild loquat's chloroplast genomes, one is Eriobotrya elliptica, and the other is an unidentified wild loquat, which we named "YN-1". Their sizes are 159,471 bp and 159,399 bp, respectively. We also assembled a cultivated loquat named 'JFZ', its chloroplast genome size is 159,156 bp. A comparative study was conducted with six distinct species of loquats, including five wild loquats and one cultivated loquat. The results showed that both E. elliptica and "YN-1" have 127 genes, one gene more than E. fragrans, which is psbK. Regions trnF-GAA-ndhJ, petG-trnP-UGG, and rpl32-trnL-UAG were found to exhibit high variability. It was discovered that there was a positive selection on rpl22 and rps12. RNA editing analysis found several chilling stress-specific RNA editing sites, especially in rpl2 gene. Phylogenetic analysis results showed that "YN-1" is closely related to E. elliptica, E. obovata and E. henryi.


Assuntos
Eriobotrya , Genoma de Cloroplastos , Filogenia , Eriobotrya/genética , Edição de RNA/genética
20.
Int J Biol Macromol ; 277(Pt 1): 134008, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39032879

RESUMO

In this study, an active film composed of gallic acid (GA), chitosan (CS), and cellulose nanocrystals (CNC) was prepared using a solution casting method and synergistic photodynamic inactivation (PDI) technology. Characterization of the film showed that the CS-CNC-GA composite film had high transparency and UV-blocking ability. The addition of GA (0.2 %-1.0 %) significantly enhanced the mechanical properties, water resistance, and thermal stability of the film. The tensile strength increased up to 46.30 MPa, and the lowest water vapor permeability was 1.16 × e-12 g/(cm·s·Pa). The PDI-treated CS-CNC-GA1.0 composite film exhibited significantly enhanced antibacterial activity, with inhibition zone diameters of 31.83 mm against Staphylococcus aureus and 21.82 mm against Escherichia coli. The CS-CNC-GA composite film also showed good antioxidant activity. Additionally, the CS-CNC-GA1.0 composite film generated a large amount of singlet oxygen under UV-C light irradiation. It was found that using the CS-CNC-GA1.0 composite film for packaging and storage of oysters at 4 °C effectively delayed the increase in pH, total colony count, and lipid oxidation in oysters. In conclusion, the CS-CNC-GA composite film based on PDI technology has great potential for applications in the preservation of aquatic products.


Assuntos
Antibacterianos , Celulose , Quitosana , Ácido Gálico , Ácido Gálico/química , Ácido Gálico/farmacologia , Quitosana/química , Celulose/química , Antibacterianos/farmacologia , Antibacterianos/química , Antioxidantes/química , Antioxidantes/farmacologia , Escherichia coli/efeitos dos fármacos , Embalagem de Alimentos/métodos , Staphylococcus aureus/efeitos dos fármacos , Nanopartículas/química , Permeabilidade , Nanocompostos/química , Resistência à Tração , Raios Ultravioleta
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