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2.
Nat Immunol ; 20(8): 992-1003, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31263279

RESUMEN

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.


Asunto(s)
Interleucina-17/inmunología , Linfocitos/inmunología , Psoriasis/patología , Piel/patología , Células Cultivadas , Humanos , Interleucina-1beta/inmunología , Subunidad p19 de la Interleucina-23/inmunología , Interleucina-4/inmunología , Linfocitos/citología , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/metabolismo , Proteínas Proto-Oncogénicas c-kit/metabolismo , Psoriasis/inmunología , Receptores CCR10/metabolismo , Piel/inmunología , Factor de Crecimiento Transformador beta/metabolismo
3.
Metab Brain Dis ; 39(4): 625-633, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38416338

RESUMEN

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.


Asunto(s)
Apoptosis , Glioma , Ratones Desnudos , Compuestos de Organoselenio , Estrés Oxidativo , Especies Reactivas de Oxígeno , Humanos , Glioma/tratamiento farmacológico , Glioma/metabolismo , Glioma/patología , Apoptosis/efectos de los fármacos , Compuestos de Organoselenio/farmacología , Compuestos de Organoselenio/uso terapéutico , Animales , Especies Reactivas de Oxígeno/metabolismo , Línea Celular Tumoral , Estrés Oxidativo/efectos de los fármacos , Ratones , Antineoplásicos/farmacología , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto , Proliferación Celular/efectos de los fármacos , Ratones Endogámicos BALB C
4.
BMC Musculoskelet Disord ; 25(1): 129, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38347518

RESUMEN

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.


Asunto(s)
Osteoporosis , Tornillos Pediculares , Fusión Vertebral , Humanos , Análisis de Elementos Finitos , Fusión Vertebral/métodos , Fenómenos Biomecánicos , Rango del Movimiento Articular , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Osteoporosis/cirugía
5.
Proc Natl Acad Sci U S A ; 118(20)2021 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-33986115

RESUMEN

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.


Asunto(s)
Eriobotrya/genética , Duplicación de Gen , Poliploidía , Triterpenos/metabolismo , Vías Biosintéticas , Eriobotrya/metabolismo , Genoma de Planta
6.
BMC Musculoskelet Disord ; 24(1): 85, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36726086

RESUMEN

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.


Asunto(s)
Tornillos Pediculares , Fusión Vertebral , Humanos , Análisis de Elementos Finitos , Fenómenos Biomecánicos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Rango del Movimiento Articular , Impresión Tridimensional
7.
BMC Musculoskelet Disord ; 24(1): 695, 2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37649054

RESUMEN

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.


Asunto(s)
Fracturas Óseas , Tornillos Pediculares , Humanos , Análisis de Elementos Finitos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Hueso Esponjoso
8.
J Environ Manage ; 335: 117514, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-36841000

RESUMEN

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.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Agua , China , Suelo
9.
Cell Mol Biol (Noisy-le-grand) ; 67(6): 281-290, 2022 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-35818185

RESUMEN

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.


Asunto(s)
Houttuynia , Antioxidantes/farmacología , Flavonoides/farmacología , Houttuynia/química , Humanos , Fenoles/farmacología , Polifenoles , Ultrasonido
10.
BMC Musculoskelet Disord ; 23(1): 851, 2022 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-36076212

RESUMEN

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.


Asunto(s)
Laminoplastia , Adulto , Humanos , Fenómenos Biomecánicos , Vértebras Cervicales/diagnóstico por imagen , Vértebras Cervicales/cirugía , Análisis de Elementos Finitos , Laminoplastia/efectos adversos , Rango del Movimiento Articular , Titanio
11.
BMC Musculoskelet Disord ; 23(1): 1122, 2022 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-36550443

RESUMEN

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).


Asunto(s)
Tornillos Pediculares , Fusión Vertebral , Humanos , Análisis de Elementos Finitos , Fusión Vertebral/métodos , Fenómenos Biomecánicos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Tornillos Óseos , Rango del Movimiento Articular
12.
Ecotoxicol Environ Saf ; 156: 294-300, 2018 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-29571107

RESUMEN

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.


Asunto(s)
Carbón Orgánico/química , Níquel/química , Curtiembre , Administración de Residuos , Adsorción , Calor , Concentración de Iones de Hidrógeno , Modelos Teóricos , Nitrógeno/química , Presión , Silicatos/química , Espectroscopía Infrarroja por Transformada de Fourier , Termodinámica , Contaminantes Químicos del Agua/química
13.
Neurobiol Learn Mem ; 130: 105-17, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26872592

RESUMEN

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.


Asunto(s)
Ambiente , Fructosa/administración & dosificación , Histona Desacetilasas/metabolismo , Aprendizaje/efectos de los fármacos , Memoria/efectos de los fármacos , Efectos Tardíos de la Exposición Prenatal/metabolismo , Animales , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Cognición/efectos de los fármacos , Femenino , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Masculino , Embarazo , Ratas , Ratas Sprague-Dawley , Aprendizaje Espacial/efectos de los fármacos
14.
PLoS Comput Biol ; 9(7): e1003140, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23874182

RESUMEN

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.


Asunto(s)
Alelos , Células Madre Embrionarias/citología , Proteínas de Homeodominio/genética , Animales , Expresión Génica , Ratones , Proteína Homeótica Nanog
15.
Ambio ; 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38564103

RESUMEN

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.

16.
Lung Cancer ; 189: 107451, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38354535

RESUMEN

OBJECTIVES: Canakinumab, an interleukin-1 beta inhibitor, previously showed reduced lung cancer incidence and mortality (CANTOS). Here, we compare the efficacy/safety of canakinumab versus placebo in patients with advanced non-small cell lung cancer (NSCLC) who had progressed after platinum-based doublet chemotherapy (PDC) and immunotherapy. MATERIALS AND METHODS: CANOPY-2, a randomized, double-blind, phase 3 trial, enrolled adult patients with stage IIIB/IV NSCLC, without EGFR or ALK alterations, who had received one prior PDC regimen and one prior programmed death-1/programmed death-ligand 1 inhibitor and experienced subsequent disease progression. Patients were randomized to canakinumab plus docetaxel or placebo plus docetaxel. RESULTS: A total of 237 patients were randomly allocated: 120 (51 %) to canakinumab and 117 (49 %) to placebo, stratified by histology and prior lines of therapy. Three patients in the placebo arm did not receive study treatment. The trial did not meet its primary endpoint of overall survival: median 10.6 months (95 % confidence interval [CI], 8.2-12.4) for the canakinumab arm and 11.3 months (95 % CI, 8.5-13.8) for the placebo arm (hazard ratio, 1.06 [95 % CI, 0.76-1.48]; one-sided P-value = 0.633). AEs (any grade) were reported in 95 % of patients in the canakinumab group and in 98 % of patients in the placebo group. Grade 3-4 AEs were experienced by 62 % and 64 % of patients in the canakinumab and placebo groups, respectively, and grade 5 AEs were experienced by 8 % and 5 %. Prespecified, post-hoc subgroup analyses showed that patients with undetected circulating tumor DNA (ctDNA) and/or lower levels (< 10 mg/L) of C-reactive protein (CRP) achieved longer progression-free and overall survival than those with detected ctDNA or higher (≥ 10 mg/L) CRP levels. There was no association with treatment arm. CONCLUSION: Adding canakinumab to docetaxel did not provide additional benefit for patients with advanced NSCLC who had progressed after PDC and immunotherapy. CLINICAL REGISTRATION: NCT03626545.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Adulto , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Docetaxel/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Inmunoterapia
17.
Heliyon ; 9(8): e18430, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37533976

RESUMEN

Background: Exposure to Migraine may be one of the risk factors for the onset of rheumatoid arthritis (RA), while the relationship between the two is debatable. In this study, the connection between migraine and the risk of RA was investigated using a systematic review and meta-analysis of the pertinent literature. Methods: Up to July 2022, the PubMed, EMBASE, Web of Science (WOS), and scopus databases were employed to search for observational studies on the risk of RA in migraineurs. The effect sizes were pooled using a random-effects model or a fixed-effects model. Results: Out of 2345 records, 5 studies (3 case and control studies and 2 cohort studies) were identified and included in the meta-analysis. According to a pooled analysis, migraine sufferers had a higher chance of developing RA (pooled adjusted effect estimate: 1.94, 95% confidence interval: 1.74-2.17; p < 0.01). Conclusions: Migraine can be legitimately regarded as a risk factor for RA since this study demonstrated a relationship between migraine and RA. This conclusion should be treated with caution due to low power and precision. Rigorous design and larger sample sizes of studies are needed to verify the findings.

18.
Front Chem ; 11: 1163178, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37153526

RESUMEN

A self-assembled tetrahedral cage results from two C 3-symmetry building blocks, namely, homooxacalix[3]arene tricarboxylate and uranyl cation, as demonstrated by X-ray crystallography. In the cage, four metals coordinate at the lower rim with the phenolic and ether oxygen atoms to shape the macrocycle with appropriate dihedral angles for tetrahedron formation, whereas four additional uranyl cations further coordinate at the upper-rim carboxylates to finalize the assembly. Counterions dictate the filling and porosity of the aggregates, whereas potassium induces highly porous structures, and tetrabutylammonium yields compact, densely packed frameworks. The tetrahedron metallo-cage complements our previous report (Pasquale et al., Nat. Commun., 2012, 3, 785) on uranyl-organic frameworks (UOFs) from calix[4]arene and calix[5]arene carboxylates (octahedral/cubic and icosahedral/dodecahedral giant cages, respectively) and completes the assembly of all five Platonic solids from just two chemical components.

19.
J Orthop Surg Res ; 18(1): 366, 2023 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-37198649

RESUMEN

BACKGROUND: Pelvic parameters have been taken into consideration for the evaluation of the outcomes of bracing in AIS. To discuss the stress required to correct the pelvic deformity related to Lenke5 adolescent idiopathic scoliosis (AIS) by finite element analysis, and provide a reference for the shaping of the pelvic region of the brace. METHODS: An three-dimensional (3D) corrective force on the pelvic area was defined. Computed tomography images were used to reconstruct a 3D model of Lenke5 AIS. Computer-aided engineering software Abaqus was used to implement finite element analysis. By adjusting the magnitude and position of corrective forces, coronal pelvic coronal plane rotation (PCPR) and Cobb angle (CA) of lumbar curve in the coronal plane, horizontal pelvic axial plane rotation, and apical vertebra rotation (AVR) were minimized to achieve the best effect on the spine and pelvic deformity correction. The proposed corrective conditions were divided into three groups: (1) forces applied on X-axis; (2) forces applied both in the X- and Y-axis; and (3) forces applied along the X-, Y-, and Z-axis at the same time. RESULTS: In three groups, CA correction reduced by 31.5%, 42.5%, and 59.8%, and the PCPR changed to 12°, 13°, and 1° from 6.5°, respectively. The best groups of correction forces should simultaneously locate on the sagittal, transverse, and coronal planes of the pelvis. CONCLUSIONS: For Lenke5 AIS, 3D correction forces can sufficiently reduce scoliosis and pelvic asymmetrical state. Force applied along the Z-axis is vital to correct the pelvic coronal pelvic tilt associated with Lenke5 AIS.


Asunto(s)
Cifosis , Escoliosis , Humanos , Adolescente , Escoliosis/diagnóstico por imagen , Análisis de Elementos Finitos , Estudios Retrospectivos , Columna Vertebral , Ácido Dioctil Sulfosuccínico , Vértebras Torácicas
20.
Sci Transl Med ; 15(689): eabm8729, 2023 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-36989374

RESUMEN

In the context of cancer, clonal hematopoiesis of indeterminate potential (CHIP) is associated with the development of therapy-related myeloid neoplasms and shorter overall survival. Cell-free DNA (cfDNA) sequencing is becoming widely adopted for genomic screening of patients with cancer but has not been used extensively to determine CHIP status because of a requirement for matched blood and tumor sequencing. We present an accurate classification approach to determine the CH status from cfDNA sequencing alone, applying our model to 4324 oncology clinical cfDNA samples. Using this method, we determined that 30.3% of patients in this cohort have evidence of CH, and the incidence of CH varies by tumor type. Matched RNA sequencing data show evidence of increased inflammation, especially neutrophil activation, within the tumors and tumor microenvironments of patients with CH. In addition, patients with CH had evidence of neutrophil activation systemically, pointing to a potential mechanism of action for the worse outcomes associated with CH status. Neutrophil activation may be one of many mechanisms, however, because patients with estrogen receptor-positive breast cancer harboring TET2 frameshift mutations had worse outcomes but similar neutrophil frequencies to patients without CH. Together, these data show the feasibility of detecting CH through cfDNA sequencing alone and an application of this method, demonstrating increased inflammation in patients with CH both systemically and in the tumor microenvironment.


Asunto(s)
Ácidos Nucleicos Libres de Células , Neoplasias , Humanos , Hematopoyesis Clonal/genética , Ácidos Nucleicos Libres de Células/genética , Hematopoyesis/genética , Neoplasias/patología , Inflamación , Análisis de Secuencia de ADN , Mutación/genética , Microambiente Tumoral
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