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1.
Eur J Orthod ; 46(3)2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38733349

RESUMEN

OBJECTIVES: The biomechanics in achieving molar distalization may differ between fixed appliances and clear aligners in the control of tooth movement. The objective of this study was to compare the treatment effects between clear aligners (CA) and fixed appliances (FA) in patients treated with miniscrew-assisted molar distalization. METHODS: The sample consisted of 46 subjects with mild-to-moderate crowding. A total of 22 patients treated with clear aligners (age, 25.66 ±â€…6.11 years old) and 24 patients treated with fixed appliances (age, 24.04 ±â€…4.95 years old) for miniscrew-assisted molar distalization were included in this study. The dental and skeletal changes were evaluated by the pre- and post-treatment lateral cephalograms. RESULTS: Significant changes were found with the vertical variables SN-OP angle (2.24 ±â€…3.22°, P < .05) and SN-MP angle (0.73 ±â€…1.15°, P < .05) for the FA group when compared with the CA group (SN-OP angle 0.41 ±â€…2.26° and SN-MP angle -0.21 ±â€…1.38°, P > .05). Both treatment groups achieved a 2-3 mm. molar distalization with significant intrusion of the upper molars. The CA group showed significantly less distal tipping of molars (U6^PP angle -2.29 ±â€…3.29° and L6^MP angle -2.92 ±â€…2.49°, P < .05) compared to the FA group (-5.24 ±â€…4.28° and -5.53 ±â€…5.03°, P < .05). In addition, significant retraction and lingual inclination of the upper and lower incisors were found in both groups. LIMITATIONS: The changes of tooth position were evaluated by 2D lateral cephalograms, not 3D measurements. CONCLUSIONS: Compared to fixed appliances, clear aligners seemed to have better control of vertical dimension and distal tipping of molars in patients treated with miniscrew-assisted molar distalization.


Asunto(s)
Tornillos Óseos , Cefalometría , Diente Molar , Métodos de Anclaje en Ortodoncia , Aparatos Ortodóncicos Fijos , Técnicas de Movimiento Dental , Humanos , Técnicas de Movimiento Dental/instrumentación , Técnicas de Movimiento Dental/métodos , Masculino , Femenino , Adulto , Métodos de Anclaje en Ortodoncia/instrumentación , Métodos de Anclaje en Ortodoncia/métodos , Adulto Joven , Diseño de Aparato Ortodóncico , Maloclusión/terapia , Resultado del Tratamiento , Maxilar , Mandíbula , Aparatos Ortodóncicos Removibles , Incisivo , Dimensión Vertical
2.
J Phys Chem Lett ; : 5467-5475, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38748088

RESUMEN

Two-dimensional (2D) covalent organic frameworks (COFs) assembled using building blocks have been widely employed in photocatalysis due to their customizable optoelectronic characteristics and porous structure, which facilitate charge carrier and mass movement. Nevertheless, the development of COF photocatalysts encounters a continuous obstacle in enhancing the efficiency of photocatalysis, impeded by a limited comprehension of the orbital interaction between molecular fragments and linkers. In this study, we present a model that examines the interaction between molecular fragments in an imine-based COF at the frontier molecular orbital level, enabling us to comprehend the impact of manipulating linkers on light adsorption, exciton efficiency, and catalytic activity. Our findings demonstrate that altering the connecting orientation of 14 R-C=N-R imine linkers in 2D COFs can enhance solar-to-hydrogen (STH) efficiency under visible light from 2.76% to 4.24%. This research has the potential to provide a valuable model for refining photocatalysts with enhanced photocatalytic performance.

3.
Sensors (Basel) ; 24(3)2024 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-38339706

RESUMEN

In recent years, significant progress has been witnessed in the field of deep learning-based object detection. As a subtask in the field of object detection, traffic sign detection has great potential for development. However, the existing object detection methods for traffic sign detection in real-world scenes are plagued by issues such as the omission of small objects and low detection accuracies. To address these issues, a traffic sign detection model named YOLOv7-Traffic Sign (YOLOv7-TS) is proposed based on sub-pixel convolution and feature fusion. Firstly, the up-sampling capability of the sub-pixel convolution integrating channel dimension is harnessed and a Feature Map Extraction Module (FMEM) is devised to mitigate the channel information loss. Furthermore, a Multi-feature Interactive Fusion Network (MIFNet) is constructed to facilitate enhanced information interaction among all feature layers, improving the feature fusion effectiveness and strengthening the perception ability of small objects. Moreover, a Deep Feature Enhancement Module (DFEM) is established to accelerate the pooling process while enriching the highest-layer feature. YOLOv7-TS is evaluated on two traffic sign datasets, namely CCTSDB2021 and TT100K. Compared with YOLOv7, YOLOv7-TS, with a smaller number of parameters, achieves a significant enhancement of 3.63% and 2.68% in the mean Average Precision (mAP) for each respective dataset, proving the effectiveness of the proposed model.

4.
J Pineal Res ; 76(1): e12935, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38241675

RESUMEN

Circadian misalignment (CM) caused by shift work can increase the risk of mood impairment. However, the pathological mechanisms underlying these deficits remain unclear. In the present study, we used long-term variable photoperiod (L-VP) in wild-type mice to better simulate real-life shift patterns and study its effects on the prefrontal cortex (PFC) and hippocampus, which are closely related to mood function. The results showed that exposure to L-VP altered the activity/rest rhythms of mice, by eliciting phase delay and decreased amplitude of the rhythms. Mice with CM developed anxiety and depression-like manifestations and the number of mature oligodendrocytes (OL) was reduced in the medial prefrontal cortex and hippocampal CA1 regions. Mood impairment and OL reduction worsened with increased exposure time to L-VP, while normal photoperiod restoration had no effect. Mechanistically, we identified upregulation of Bmal1 in the PFC and hippocampal regions of CM mice at night, when genes related to mature OL and myelination should be highly expressed. CM mice exhibited significant inhibition of the protein kinase B (AKT)/mTOR signaling pathway, which is directly associated to OL differentiation and maturation. Furthermore, we demonstrated in the OL precursor cell line Oli-Neu that overexpression of Bmal1 inhibits AKT/mTOR pathway and reduces the expression of genes OL differentiation. In conclusion, BMAL1 might play a critical role in CM, providing strong research evidence for BMAL1 as a potential target for CM therapy.


Asunto(s)
Factores de Transcripción ARNTL , Ritmo Circadiano , Melatonina , Animales , Ratones , Ansiedad/genética , Factores de Transcripción ARNTL/genética , Factores de Transcripción ARNTL/metabolismo , Factores de Transcripción ARNTL/farmacología , Ritmo Circadiano/genética , Ritmo Circadiano/fisiología , Depresión/genética , Melatonina/farmacología , Oligodendroglía/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Serina-Treonina Quinasas TOR/metabolismo
5.
PhytoKeys ; 232: 59-66, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37720267

RESUMEN

Staurantherafloribunda F.Su, C.Y.Hao & K.Tan, a new species of Gesneriaceae from Yunnan, China, is described and illustrated here. It is morphologically similar to S.grandifolia Benth. in the shape of corolla, stigma, leaves and the number of stamens. However, it can be readily distinguished from the compared species by its dense cymes, leaf indumentum, lack of a corolla spur, calyx colour and stamen shape. The description of the new species, photographs, detailed descriptions, notes on etymology, distribution and habitat, as well as comparisons with morphologically similar species, are provided.

6.
Materials (Basel) ; 16(11)2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37297262

RESUMEN

A novel annealing process of controlled heating rate is used to produce severe cold-formed aluminum plates, which are processed into aluminum foil and mainly used for high-voltage electrolytic capacitor anodes. The experiment in this study focused on various aspects such as microstructure, recrystallization behavior, grain size, and grain boundary characteristics. The results revealed a comprehensive influence of cold-rolled reduction rate, annealing temperature, and heating rate on recrystallization behavior and grain boundary characteristics during the annealing process. The heating rate applied plays a crucial role in controlling the recrystallization process and the subsequent grain growth, which ultimately determines whether or not the grains will become larger. In addition, as the annealing temperature rises, the recrystallized fraction increases and the grains size decreases; conversely, the recrystallized fraction decreases as the heating rate increases. When the annealing temperature remains constant, the recrystallization fraction increases with a greater deformation degree. Once complete recrystallization occurs, the grain will undergo secondary growth and may even subsequently become coarser. If the deformation degree and annealing temperature remain constant, the increased heating rate will result in a lower recrystallization fraction. This is due to the inhibition of recrystallization, and most of the aluminum sheet even remains in a deformed state before recrystallization. This kind of microstructure evolution, grain characteristic revelation, and recrystallization behavior regulation can provide effective help for enterprise engineers and technicians to guide the production of capacitor aluminum foil to a certain extent, so as to improve the quality of aluminum foil and increase the electric storage performance.

7.
Autism Res ; 16(6): 1124-1137, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37163546

RESUMEN

Autism spectrum disorder (ASD) is associated with abnormal brain imaging findings, but descriptions thereof are inconsistent. The aim of the present study was to investigate brain abnormalities in young children with ASD using a combination of structural and functional brain magnetic resonance imaging (MRI). Structural and resting-state functional MRI was performed in 67 children with ASD (aged 2-7 years) and 39 age-matched typically developing (TD) controls. Voxel-based morphometry was used to evaluate differences in brain structure between groups. Topologic parameters of the functional brain network were compared by graph theoretic analysis and network connectomes were compared with network-based statistics. A support vector machine (SVM) was used to discriminate between ASD and TD groups. Results demonstrated young children with ASD had increased gray matter volumes (GMVs) in the right medial superior frontal gyrus and left fusiform gyrus compared with the TD group. The ASD group had altered subnetwork connectivity in frontal and temporal lobes and other social cognition-related brain regions. Functional connectivity in the left superior temporal gyrus and left temporal pole of the middle temporal gyrus was positively correlated with adaptability and language developmental quotient (DQ) in children with ASD. The combination of the brain structural and functional features had 86.2% accuracy in discriminating between ASD and TD. The present study shows that young children with ASD have altered GMVs and functional networks in social cognition-related brain regions, which are potential neuroimaging biomarkers for ASD.


Asunto(s)
Trastorno del Espectro Autista , Conectoma , Humanos , Niño , Preescolar , Sustancia Gris/diagnóstico por imagen , Trastorno del Espectro Autista/diagnóstico por imagen , Cognición Social , Mapeo Encefálico/métodos , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos
8.
J Stroke Cerebrovasc Dis ; 32(7): 107142, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37105127

RESUMEN

OBJECTIVE: To explore the effects of different doses of dopamine receptor agonist pramipexole on neurobehaviors and changes of mitochondrial membrane potential in rats with global cerebral ischemia-reperfusion injury. METHODS: A total of 75 SPF Sprague-Dawley male rats were randomly divided into sham group (n=20), model group (n=20), pramipexole administration group (n=35). The rat model of global cerebral ischemia-reperfusion injury was prepared by the modified Pulsinelli's four-vessel occlusion method. Pramipexole administration group was administered intraperitoneally in rats with global cerebral ischemia-reperfusion injury at different doses of pramipexole 0.25 mg/kg, 0.5 mg/kg, 1 mg/kg, 2 mg/kg, once a day for 14 consecutive days. Based on the results of modified neurological severity scores, open field test and morphology by Nissl's staining to determine the optimal dose of pramipexole. Mitochondrial membrane potential in the optimal dose of pramipexole administration group were measured by the JC-1 fluorescent probe staining method. RESULTS: 1. Different doses of pramipexole 0.25 mg/kg, 0.5 mg/kg, 1 mg/kg, and 2 mg/kg, were used as drug administration in rats with global cerebral ischemia-reperfusion injury for 14 consecutive days, and we found that all four doses of pramipexole could improve the modified neurological severity scores of rats with global cerebral ischemia-reperfusion injury to varying degrees, but only 0.5 mg/kg pramipexole at 1, 3, 7 and 14 days consistently reduced modified neurological severity scores and improved neurological function in rats with global cerebral ischemia-reperfusion injury. In the open-field test, only 0.5 mg/kg pramipexole increased the number of entries into the central zone, duration spent in the central zone, total distance travelled in the open field and average velocity, which improved the spontaneous activities and reduced anxiety and depression of rats with global cerebral ischemia-reperfusion injury. 2. Different doses of pramipexole 0.25 mg/kg, 0.5 mg/kg, 1 mg/kg, and 2 mg/kg for 14 consecutive days significantly increased the number of surviving neurons in the hippocampal CA1 subfield in rats with global cerebral ischemia-reperfusion injury to varying degrees. Based on these results, we tentatively found that 0.5 mg/kg pramipexole may be the optimal dose in all of the above. 3. We found that 0.5 mg/kg pramipexole significantly increased the mitochondrial membrane potential in rats after global cerebral ischemia-reperfusion injury. CONCLUSION: Different doses of dopamine receptor agonist pramipexole improved neurological function of rats with global cerebral ischemia-reperfusion injury to varying degrees, and 0.5 mg/kg pramipexole may be the optimal dose in all of the above. Pramipexole may produce neuroprotective effects by protecting neurons in the hippocampus and improving the mitochondrial membrane potential after global cerebral ischemia-reperfusion injury.


Asunto(s)
Isquemia Encefálica , Daño por Reperfusión , Ratas , Masculino , Animales , Pramipexol/farmacología , Ratas Sprague-Dawley , Agonistas de Dopamina/farmacología , Potencial de la Membrana Mitocondrial , Isquemia Encefálica/tratamiento farmacológico , Infarto Cerebral , Daño por Reperfusión/tratamiento farmacológico
9.
Adv Mater ; 35(17): e2210826, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36731534

RESUMEN

Rechargeable sodium-metal batteries (RSMBs) with high energy density and low cost are attracting extensive attention as promising energy-storage technologies. However, the poor cyclability and safety issues caused by unstable solid electrolyte interphase (SEI) structure and dendrite issues limit their practical application. Herein, it is theoretically predicted that constructing the Ni3 S2 /Ni3 P heterostructure with high work function can lower the Fermi energy level, and therefore effectively suppressing continuous electrolyte decomposition derived from the electron-tunneling effect after long-term sodiation process. Furthermore, the Ni3 S2 /Ni3 P heterostructure on 3D porous nickel foam (Ni3 S2 /Ni3 P@NF) is experimentally fabricated as an advanced Na-anode current collector. The seamless Ni3 S2 /Ni3 P heterostructure not only offers abundant active sites to induce uniform Na+ deposition and enhance ion-transport kinetics, but also facilitates the formation of stable SEI for dendrite-free sodium anode, which are confirmed by cryogenic components transmission electron microscopy tests and in situ spectroscopy characterization. As a result, the Na-composite anode (Ni3 S2 /Ni3 P@NF@Na) delivers stable plating/stripping process of 5000 h and high average Coulombic efficiency of 99.7% over 2500 cycles. More impressively, the assembled sodium-ion full cell displays ultralong cycle life of 10 000 cycles at 20 C. The strategy of stabilizing the sodium-metal anode gives fundamental insight into the potential construction of advanced RSMBs.

10.
J Exp Bot ; 74(6): 2047-2066, 2023 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-36622787

RESUMEN

Grapevine downy mildew, caused by the oomycete Plasmopara viticola, is one of the most significant production challenges for the grape and wine industry. P. viticola injects a plethora of effectors into its host cells to disrupt immune processes, but the mechanisms by which these effectors act at the molecular level have not been well characterized. Herein, we show that a candidate P. viticola avirulence homolog (Avh) RxLR effector gene, designated PvAvh77, was strongly up-regulated during the initial stages of P. viticola infection in Vitis vinifera. Further experiments demonstrated that PvAvh77 could trigger non-specific cell death when expressed in the wild grapevine Vitis riparia and in tobacco (Nicotiana benthamiana and Nicotiana tabacum). In addition, a truncated form of PvAvh77, designated PvAvh77-M2, was more active in inducing cell death in N. benthamiana and V. riparia than full-length PvAvh77. Ectopic expression of PvAvh77 in V. vinifera 'Thompson Seedless' leaves neutralized host immunity and enhanced colonization by P. viticola, and the immune-inhibiting activity of PvAvh77 on susceptible Eurasian grapevine depended on its nuclear localization. Using a yeast signal sequence trap approach, we showed that the signal peptide of PvAvh77 is functional in yeast. Moreover, PvAvh77 with a signal peptide stimulated plant immune responses in the apoplast. Notably, application of exogenous purified PvAvh77-M2 effectively initiated defence responses in grapevine extracellularly, as evidenced by increased accumulation of salicylic acid and H2O2, and reduced infection of inoculated P. viticola. In summary, we identified a novel effector, PvAvh77, from P. viticola, which has the potential to serve as an inducer of plant immunity.


Asunto(s)
Oomicetos , Phytophthora infestans , Vitis , Saccharomyces cerevisiae , Peróxido de Hidrógeno/metabolismo , Enfermedades de las Plantas , Nicotiana/genética , Vitis/genética , Vitis/metabolismo , Muerte Celular , Señales de Clasificación de Proteína , Resistencia a la Enfermedad
11.
J Transl Med ; 20(1): 352, 2022 08 06.
Artículo en Inglés | MEDLINE | ID: mdl-35933342

RESUMEN

PURPOSE: The purpose of this study was to observe the harm of circadian misalignment (CM), caused by an inverted photoperiod (IP), on the hearts of the adolescent Wistar rats, and to explore the mechanisms leading to harm. METHODS: An IP was used to create a CM model. A total of 174 Wistar rats were randomly divided into circadian alignment (CA) and CM groups (87 rats per group). The different activity rhythms of the two groups of rats were adjusted through different light/dark cycles for 90 days. We recorded the rhythmic activity trajectory and sleep time of the rats. After 90 days of modeling, we performed various analyses (i.e., blood pressure, weight, cardiac ultrasound tests, serological tests, cardiac tissue immunofluorescence, immunohistochemistry, transmission electron microscopy on myocardial mitochondria, western blotting, and quantitative polymerase chain reactions). RESULTS: (1) The IP protocol caused CM in rats. (2) CM rats showed significantly higher blood pressure during the day (resting phase). They also showed significantly higher serum levels of angiotensin II and epinephrine during the day compared to the CA rats. (3) CM caused up-regulation of gene expression of adrenergic receptors α1 (α1-AR) and ß1 (ß1-AR) and down-regulation of the glucocorticoid receptor (Gr) gene expression in rat hearts. It also caused downregulation of Bmal1 expression. In addition, the changes in Bmal1 and Per2 correlated with the changes in ß1-AR and α1-AR. (4) CM had adverse effects on multiple molecular proteins of the heart. (5) CM increased the collagen fibers in the rat heart and increased the destruction of mitochondria. (6) Eventually, CM caused a decrease in the pumping function of the heart and decreased the coronary blood flow rate. CONCLUSIONS: (1) CM significantly affected the cardiac structure and function in the adolescent rats through a variety of mechanisms. (2) CM can regulate the expression of myocardial clock genes, and it is likely to have an impact on the heart through this pathway.


Asunto(s)
Factores de Transcripción ARNTL , Proteínas Circadianas Period , Factores de Transcripción ARNTL/genética , Factores de Transcripción ARNTL/metabolismo , Animales , Ritmo Circadiano , Regulación de la Expresión Génica , Corazón/fisiología , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/metabolismo , Ratas , Ratas Wistar
12.
Plant J ; 112(1): 104-114, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35929367

RESUMEN

Grapevine downy mildew, caused by Plasmopara viticola, is one of the most devastating diseases in viticulture. Plasmopara viticola secretes RxLR effectors to modulate immune responses in grapevine. Here, we report an RxLR effector RxLR50253 from P. viticola that can interfere with plant immune response and thus promote pathogen colonization. RxLR50253 was induced at an early stage of P. viticola infection and could suppress elicitor (INF1 and Bax)-triggered cell death. RxLR50253 promote pathogen colonization in both tobacco and grapevine leaves. VpBPA1 was found to be the host target of RxLR50253 by yeast two-hybrid screening, and interaction between RxLR50253 and VpBPA1 was confirmed by multiple in vivo and in vitro assays. Further analysis revealed that VpBPA1 promoted pathogen colonization and decreased H2 O2 accumulation in transgenic tobacco and grapevine, while there was enhanced resistance and H2 O2 accumulation in NbBPA1-silenced Nicotiana benthamiana leaves. Moreover, transient expression of VpBPA1 in NbBPA1-silenced N. benthamiana leaves could reduce the accumulation of H2 O2 . Experiments in vivo demonstrated that RxLR50253 inhibits degradation of VpBPA1. Taken together, our findings showed that RxLR50253 targets and stabilizes VpBPA1 to attenuate plant immunity through decreasing H2 O2 accumulation during pathogen infection.


Asunto(s)
Oomicetos , Phytophthora infestans , Vitis , Enfermedades de las Plantas , Inmunidad de la Planta , Nicotiana/genética , Vitis/metabolismo , Proteína X Asociada a bcl-2/metabolismo
13.
Front Neurol ; 13: 907186, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36034313

RESUMEN

Background: Motor dysfunction in the upper extremities after stroke prohibits people with stroke from being independent in daily living. The application of fNIRS to explore brain activity under rehabilitation intervention is a research focus on neurorehabilitation. Objective: The purpose of this study was to explore, using a grip-release ring motor task, the activated changes of regions of interest and changes in motor function utilizing fNIRS technology and test scales on persons with stroke who received unilateral task-oriented therapy with a hand orthosis in the early subacute stroke period before and after intervention. The study aimed to find a sensitive motor task and region of interest first, then to evaluate the feasibility and mechanism of this rehabilitation method by utilizing fNIRS technology in the next randomized controlled trial. Methods: In this case series, eight right-handed, right hemiplegia subacute stroke persons (6 males,2 females from age 47 to 72) were enrolled. They received 30 min of unilateral task-oriented therapy without orthosis and 30 min of unilateral task-oriented therapy with orthosis (5 days/week) for 4 weeks. Activated channel numbers and beta values based on oxygenated hemoglobin concentration change using a grip-release ring motor task were estimated with fNIRS. Clinical outcome measures, including grip strength evaluation, action research arm test, and Fugl-Meyer assessment of the arm, were evaluated at the same time. Results: Individual activation analysis showed that, after intervention, Subjects 1, 2, 6, 7, and 8 had the maximum mean beta value located in the left premotor cortex, while Subjects 4 and 5 had the maximum mean beta value located in the left sensorimotor cortex. The activation analysis of Subject 3 showed the maximum mean beta value located in the right premotor cortex. Deactivations of left sensorimotor cortex, left premotor cortex, and bilateral prefrontal cortex were observed after intervention which were different from other cases. Group activation analysis showed that bilateral cerebral hemispheres were activated in all eight participants, with right hemisphere and right supplementary motor cortex activated dominantly. After the intervention, the activation of bilateral hemispheres decreased but in different brain regions; there was a trend that the activation intensity of left sensorimotor cortex, right premotor cortex, and right prefrontal cortex decreased while activation intensity of left premotor cortex and left prefrontal cortex increased. Each participant demonstrated improvements in all the clinical test scales after intervention. Conclusions: Left premotor cortex, left sensorimotor cortex, and right supplementary motor cortex may be the primary regions of interest. Grasp-release ring task was not appropriate to achieve our fNIRS research objective and a more sensitive motor task or more sensitive evaluating indicator should be used in further studies.

14.
Materials (Basel) ; 15(4)2022 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-35207942

RESUMEN

To clarify the microstructure, grain size, and recrystallization behavior during different annealing processes with controlled heating rates, the aim of this study was to investigate the effect of residual deformation energy after cold rolling and critical heating rate on cubic texture components, and grain growth behavior of aluminum plate, which was subjected to severe deformation. The experimental results revealed that the stored energy can be inferred from a calculation that fast annealing (FA) for 30 s was 2.2 times as large as slow annealing (SA) at 320 °C, which provided the driving force for grain growth during subsequent heating and resulted in a significant coarsening of grains in the FA process. In contrast, the intensity of cubic texture in SA was significantly higher than that in the FA process. A critical heating rate of 50 °C/min had been obtained to produce a homogeneous microstructure and strong cubic texture during the annealing processes with controlled heating rates and was verified by experiment. The relationship of Δηsur > 0.02ηb was as a criterion used to determine whether abnormal grain growth happened in aluminum foil, while the grain size exceeded the thickness of aluminum foil by examined calculation.

15.
Exp Neurol ; 347: 113908, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34710402

RESUMEN

Long-term shift work can cause circadian misalignment, which has been linked to anxiety and depression. However, the associated pathophysiologic changes have not been described in detail, and the mechanism underlying this association is not fully understood. To address these points, we used a rat model of CM induced by long-term variable photoperiod exposure [L-VP] (ie, for 90 days). We compared the numbers of neurons, astrocytes, and dendritic spines; dendrite morphology; long-term potentiation (LTP), long-term depression (LTD) and paired-pulse ratio (PPR); expression of glutamate receptor [N-methyl-d-aspartate receptor (NMDAR) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR)] subunits and brain-derived neurotrophic factor (BDNF) in the medial prefrontal cortex (mPFC); and the anxiety and depression behaviors between rats in the circadian misalignment (CM) and circadian alignment (CA, with normal circadian rhythm) groups. The results showed that L-VP reduced the number of neurons and astrocytes in the mPFC and decreased the number of dendritic spines, dendrite complexity, LTP, LTD, PPR, and expression of glutamate receptors (GluR1, GluR2, GluR3, NMDAR2A, and NMDAR2B) and BDNF in the mPFC. L-VP also induced anxiety and depression-like behaviors, as measured by the open field test, elevated plus-maze, sucrose preference test, and forced swim test. These results suggest that CM induces a loss of neurons and astrocytes and synaptic damage in surviving pyramidal cells in the mPFC might be involved in the pathophysiology of anxiety and depression.


Asunto(s)
Ansiedad/patología , Depresión/patología , Fotoperiodo , Corteza Prefrontal/patología , Animales , Ansiedad/etiología , Ansiedad/metabolismo , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Depresión/etiología , Depresión/metabolismo , Masculino , Técnicas de Cultivo de Órganos , Corteza Prefrontal/metabolismo , Ratas , Ratas Wistar , Receptores de N-Metil-D-Aspartato/metabolismo , Factores de Tiempo
16.
Trials ; 22(1): 507, 2021 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-34332635

RESUMEN

BACKGROUND: Enamel white spot lesions (WSLs), characterized by an opaque, matt, and chalky white appearance of enamel, are a sign of incipient caries. WSLs are common in orthodontic practice and can affect both the oral health and dental aesthetics of patients. Extensive studies have been conducted to evaluate the effectiveness of prevention or treatment for orthodontically induced enamel WSLs. However, substantial heterogeneity has been found in the outcomes used for the prevention and treatment of WSLs in literature, which prevents researchers from comparing and combining the results of different studies to draw more decisive conclusions. Therefore, we aim to develop a Core Outcome Set for trials on the prevention and treatment of Orthodontically induced enamel White Spot Lesions (COS-OWSL). METHODS: The development of COS-OWSL comprises four phases: (1) a scoping review to identify and summarize all existing outcomes that have been used in trials on the prevention or treatment of orthodontically induced WSLs; (2) qualitative interviews with orthodontic patients without (for prevention) and with WSL-affected teeth (for treatment) and relevant dental professionals to identify additional outcomes relevant to them; (3) Delphi surveys to collect opinions from key stakeholders including patients, dental professionals, and researchers and to reach a preliminary consensus; and (4) a consensus meeting to develop the final COS-OWSL. DISCUSSION: The COS-OWSL will be developed to facilitate the synthesis of evidence regarding the prevention and treatment of orthodontically induced WSLs and to promote the consistent use of relevant patient-important outcomes among future studies in this field. TRIAL REGISTRATION: Core Outcome Measures in Effectiveness Trials (COMET) initiative (the COS-WSL project) 1399.


Asunto(s)
Caries Dental , Salud Bucal , Consenso , Técnica Delphi , Caries Dental/diagnóstico , Caries Dental/prevención & control , Esmalte Dental , Humanos , Evaluación de Resultado en la Atención de Salud , Resultado del Tratamiento
17.
Am J Orthod Dentofacial Orthop ; 160(5): 659-670.e7, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34366187

RESUMEN

INTRODUCTION: The objective was to identify and summarize the outcomes and evaluation methods used in clinical trials regarding the prevention and treatment of orthodontically induced white spot lesions (WSLs). METHODS: Three electronic databases were searched to identify studies that were (1) clinical trials on prevention and/or treatment of orthodontically induced WSLs, (2) reported in English, and (3) published between January 2010 and October 2019. At least 2 authors assessed the eligibility and extracted the characteristics, outcomes, and evaluation methods from included studies. All disagreements were resolved through discussion. RESULTS: Among 1328 studies identified, 51 were eligible and included. A total of 48 different outcomes and 11 different evaluation methods were used in these studies. The most frequently used outcomes were WSLs clinical visual examination scores (n = 22, 43.1%), DIAGNOdent values (n = 14; 27.5%), fluorescence loss measured with quantitative light-induced fluorescence (QLF) (n = 10; 19.6%), and lesion area measured with QLF (n = 10; 19.6%). The most frequently used evaluation methods were clinical examination (n = 25; 49.0%), visual inspection by photographs (n = 15; 29.4%), DIAGNOdent (n = 14; 27.5%), and QLF (n = 10; 19.6%). None of the included studies reported data on quality of life. CONCLUSIONS: Substantial outcome heterogeneity exists among studies regarding the prevention and treatment of orthodontically induced WSLs. Most of the identified outcomes are aimed to assess morphologic changes of WSLs and may not reflect patient perspectives. REGISTRATION: The Core Outcome Set for trials on the prevention and treatment of enamel White Spot Lesions (COS-WSL) project was registered in the COMET Initiative database (No. 1399).


Asunto(s)
Caries Dental , Calidad de Vida , Caries Dental/etiología , Caries Dental/prevención & control , Esmalte Dental , Humanos
18.
Front Neurol ; 12: 664610, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33995261

RESUMEN

Objective: Shift work is associated with a decrease in melatonin level and perturbation of the circadian rhythm; however, it is unknown if these lead to functional brain changes. In this study, we investigated whether circadian rhythm disorders caused by shift work are related to changes in brain functional connectivity (FC) and regional homogeneity (ReHo) using whole-brain resting-state functional magnetic resonance imaging (fMRI). Methods: This prospective case-control study included nine female night shift nurses and nine age-matched female day work nurses with normal sleep rhythms. To assess sleep quality and mood, participants were asked to complete questionnaires. Serum melatonin and cortisol levels were measured. ReHo of whole-brain resting-state function and seed-based FC of the bilateral hypothalamus were compared between groups. Variables that differed significantly between groups were used to examine the association between questionnaire scores and hormone levels and fMRI data. Results: The night shift nurses had significantly lower sleep quality and melatonin levels; lower ReHo activation in the bilateral cerebellar hemisphere and higher ReHo in the bilateral occipital lobe and left parietal lobe; and higher FC from the hypothalamus to the right cingulate gyrus, right putamen, and vermis than did the day shift nurses. Activation of the right cerebellar hemisphere left superior parietal gyrus, and the right superior occipital gyrus was correlated with sleep quality scores. Moreover, activation of the right cerebellar hemisphere (r = 0.583, P = 0.011) was correlated with melatonin levels, and higher sleepiness scores were associated with stronger FC between the hypothalamus and vermis (r = 0.501, P = 0.034). Conclusions: Circadian rhythm disorder caused by night shift work can lead to a decrease in sleep quality and melatonin level, as well as a series of changes in brain FC and ReHo.

19.
J Hypertens ; 39(5): 871-879, 2021 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-33824259

RESUMEN

OBJECTIVE: The objective of this study was to investigate the effects of inverted photoperiods on the blood pressure and carotid arteries in spontaneously hypertensive rats (SHRs) and Wistar-Kyoto (WKY) rats (homologous control group). METHODS AND RESULTS: This study used two inverted photoperiods [inverted light:dark (ILD)16 : 8 and ILD12 : 12] to create the model. A total of 27 male SHR and 27 male WKY rats were randomly divided into six groups (nine rats per group): SHR (LD12 : 12), SHR (ILD16 : 8), SHR (ILD12 : 12), WKY (LD12 : 12), WKY (ILD16 : 8) and WKY (ILD12 : 12). We recorded the trajectory of the activity rhythm of the rats and performed carotid vascular ultrasound examination, MRI (arterial spin labelling) analysis and carotid biopsy. The results showed that inverted photoperiods increased the blood pressure, carotid intima-media thickness, resistance index and blood flow velocity. In addition, inverted photoperiods led to the development of carotid arterial thrombosis, significantly reduced cerebral blood flow and increased the number of collagen fibres. Moreover, it increased the expression of angiotensin receptor and low-density lipoprotein receptor in the carotid arteries, leading to decreased expression of 3-hydroxy-3-methylglutaryl-Coenzyme A reductase and nitric oxide synthase. Inverted photoperiods induced the formation of atherosclerotic plaque. Multiple results of SHR were worse than those of WKY rats. CONCLUSION: Taken together, inverted photoperiods can produce a series of adverse consequences on blood pressure and carotid arteries. Hypertension can aggravate the adverse effects of inverted photoperiods.


Asunto(s)
Grosor Intima-Media Carotídeo , Hipertensión , Animales , Presión Sanguínea , Arterias Carótidas/diagnóstico por imagen , Masculino , Fotoperiodo , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY
20.
Gland Surg ; 9(5): 1346-1353, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33224809

RESUMEN

BACKGROUND: The exact factors and mechanisms involved in the development of hematoma after breast ultrasound (US)-guided vacuum-assisted biopsy (VAB) are not clear. This study aimed to analyze the occurrence, prognosis, and risk factors of hematoma after US-guided VAB for the removal of benign breast lesions. METHODS: This was a retrospective study of consecutive female patients with breast lesions (BI-RADS 3/4a/4b and confirmed as benign by core needle biopsy) removed by percutaneous excisional biopsy by US-guided VAB at the Beijing Chaoyang Hospital from April 2016 to December 2018. Univariable analyses were conducted to identify the factors associated with hematoma (age, nodule size, laterality, nodule location, number of nodules, BI-RADS classification of ultrasound, pathology, breast shape, menstrual period, efficacy time of bandage, and hemostatic agents). Multivariable analysis was performed to identify the factors independently associated with hematoma. RESULTS: A total of 293 patients (343 breast lesions) were included. Lesion removal was successful in all cases. Hematomas ≥1 cm were found in 39 patients. Finally, 38 (97.4%) hematomas were absorbed completely within 6 months. The multivariable logistic regression analysis revealed that lesion size (P<0.001; OR: 5.775; 95% CI: 2.752-12.121), number of lesions (P=0.011; OR: 3.205, 95% CI: 1.311-7.834), and the efficacy time of bandage 12-24 h (P=0.003; OR: 5.257, 95% CI: 1.792-15.421) were independently associated with hematoma occurrence after US-guided VAB excision of breast lesions. A lesion size cut-off of 23.4 mm (AUC 0.764, 95% CI: 0.692-0.837; 59.0% sensitivity; 80.3% specificity; 77.5% accuracy; P<0.001) could predict hematoma occurrence. CONCLUSIONS: US-guided excisional VAB can effectively remove benign breast lesions. The factors independently associated with postoperative hematoma are lesion size, lesion number, and effective postoperative compression time of bandage.

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