Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 311
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Stroke Cerebrovasc Dis ; : 104793, 2020 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-32224203

RESUMO

OBJECTIVES: Although several studies have shown that interventions to lower blood lipid concentration may reduce the risk of coronary arterial disease and ischemic stroke, the correlation between serum lipid levels and hemorrhagic stroke remains controversial. To clarify any possible association between serum lipid and hematoma expansion, we examined various serum lipid indices in patients with and without early hematoma expansion. METHODS: Data of 572 intracerebral hemorrhage (ICH) patients from the cerebral small vessel disease cohort of Peking Union Medical College Hospital were retrospectively analyzed. Patients who finished the baseline brain computed tomography (CT) examination within 6 h post-ictus and the follow-up CT within 48 h after initial CT were included in the study. Hematoma expansion was delimited as an enlargement of hemorrhage volume over 33% or 12.5 mL between baseline and subsequent CT. Both uni- and multivariate logistic regression analyses were conducted to explore the association between early hematoma growth and various serum lipid indices, including triglycerides, total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), non-HDL-C, ratios of LDL-C/HDL-C and LDL-C/TC, as well as other demographic and clinical features. RESULTS: Out of 157 patients included in the analysis, hematoma growth occurred in 45 (28.7%). Only higher baseline systolic blood pressure was found to be correlated with an increased risk of hematoma growth based on both univariate (odds ratio [OR] 1.014, 95% confidence interval [CI]: 1.002-1.026, P = .024) and multivariate logistic regression analyses (OR 1.022, 95%CI: 1.008-1.037, P = .003). No associations were detected between the various serum lipid indices examined and other clinical features with a likelihood of early hematoma growth between groups or within various subgroups defined by different characteristics including age, gender, baseline Glasgow Coma Scale score, systolic blood pressure, intraventricular extension, and hematoma location. CONCLUSIONS: No association between various indices of serum lipid and hematoma growth was identified among patients and subgroups with spontaneous ICH in the Chinese population; these findings may help to guide lipid management after ICH. However, further multi-centered, larger scale studies are expected to verify our results.

2.
Nat Commun ; 11(1): 1531, 2020 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-32210233

RESUMO

Vesicle associated membrane protein 2 (VAMP2/synaptobrevin2), a core SNARE protein residing on synaptic vesicles (SVs), forms helix bundles with syntaxin-1 and SNAP25 for the SNARE assembly. Prior to the SNARE assembly, the structure of VAMP2 is unclear. Here, by using in-cell NMR spectroscopy, we describe the dynamic membrane association of VAMP2 SNARE motif in mammalian cells, and the structural change of VAMP2 upon the change of intracellular lipid environment. We analyze the lipid compositions of the SV membrane by mass-spectrometry-based lipidomic profiling, and further reveal that VAMP2 forms distinctive conformations in different membrane regions. In contrast to the non-raft region, the membrane region of cholesterol-rich lipid raft markedly weakens the membrane association of VAMP2 SNARE motif, which releases the SNARE motif and facilitates the SNARE assembly. Our work reveals the regulation of different membrane regions on VAMP2 structure and sheds light on the spatial regulation of SNARE assembly.

3.
Plant Physiol Biochem ; 150: 121-132, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32142985

RESUMO

Withering is an important biological process accompanied by dehydration and cell wall metabolism in postharvest plant organs during curing/processing and storage. However, dynamics involved in cell wall metabolism and resultant water loss during withering in postharvest tobacco leaves is not well-documented. Here, tandem mass tag (TMT)-based quantitative proteomic analysis in postharvest tobacco leaves (cultivar K326) under different withering conditions was performed. In total, 11,556 proteins were detected, among which 496 differentially abundant proteins (DAPs) were identified. To elucidate the withering mechanism of tobacco leaves, 27 DAPs associated with cell wall metabolism were screened. In particular, pectin acetylesterases, glucan endo-1,3-beta-glucosidases, xyloglucan endotransglucosylase/hydrolase, alpha-xylosidase 1-like, probable galactinol-sucrose galactosyltransferases, endochitinase A, chitotriosidase-1-like and expansin were the key proteins responsible for the withering of postharvest tobacco leaves. These DAPs were mainly involved in pectin metabolism, cellulose, hemicellulose and galactose metabolism, amino sugar and nucleotide sugar metabolism as well as cell wall expansion. Furthermore, relative water content and softness values were significantly and positively correlated. Thus, dehydration and cell wall metabolism were crucial for tobacco leaf withering under different conditions. Nine candidate DAPs were confirmed by parallel reaction monitoring (PRM) technique. These results provide new insights into the withering mechanism underlying postharvest physiological regulatory networks in plants/crops.

4.
Sensors (Basel) ; 20(3)2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32041366

RESUMO

Near-infrared (NIR) spectral sensors can deliver the spectral response of light absorbed by materials. Data analysis technology based on NIR sensors has been a useful tool for quality identification. In this paper, an improved deep convolutional neural network (CNN) with batch normalization and MSRA (Microsoft Research Asia) initialization is proposed to discriminate the tobacco cultivation regions using data collected from NIR sensors. The network structure is created with six convolutional layers and three full connection layers, and the learning rate is controlled by exponential attenuation method. One-dimensional kernel is applied as the convolution kernel to extract features. Meanwhile, the methods of L2 regularization and dropout are used to avoid the overfitting problem, which improve the generalization ability of the network. Experimental results show that the proposed deep network structure can effectively extract the complex characteristics inside the spectrum, which proves that it has excellent recognition performance on tobacco cultivation region discrimination, and it also demonstrates that the deep CNN is more suitable for information mining and analysis of big data.

5.
Chem Commun (Camb) ; 56(20): 2979-2982, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-32077882

RESUMO

A N2-selective ß-selenoalkylation of 1,2,3-triazoles with alkenes mediated by diamines has been developed. The reaction proceeds presumably via the interaction of diamines with both the triazole moiety and selenium/alkene complex to construct a U-shaped reaction intermediate. This activation mode will block the N1 position on triazoles and thus favor the N2-selective selenoamination. This stereospecific anti-addition method enables an efficient N2-selective ß-selenoalkylation of 1,2,3-triazoles under mild and open-air conditions and might find applications in the synthesis of biologically active molecules.

6.
J Am Chem Soc ; 142(8): 3729-3735, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32050069

RESUMO

Titanium alkoxide-based alkyne-alkyne reductive coupling mediated by in situ generated arylamidate is described. A high level of regioselectivity is achieved in 37 examples, where (E,E)-dienes are exclusively formed. To the best of our knowledge, this study represents the first example of an apparent amide and carbamate directing effect in metal-mediated reductive coupling.

7.
Med Phys ; 2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31901143

RESUMO

PURPOSE: To apply an imaging metric of the structural SIMilarity (SSIM) index to the radiotherapy dose verification field and evaluate its capability to reveal the different types of errors between two dose distributions. METHOD: The SSIM index consists of three sub-indices: luminance, contrast, and structure. Given two images, luminance analysis compares the local mean result, contrast analysis compares the local standard deviation, and the structure index represents the local Pearson correlation. Three test error patterns (absolute dose error, dose gradient error, and dose structure error) were designed to characterize the response of SSIM and its sub-indices and establish the correlation between the indices and different dose error types. After establishing the correlation, four radiotherapy plans (one MLC picket-fence test plan, one brain stereotactic radiotherapy plan, and two head-and-neck plans) were tested by computing each index and compared with the gamma analysis results to determine their similarities and differences. RESULTS: Among the three test error patterns, the luminance index decreased from 1 to 0.1 when the absolute dose agreement fell from 100% to 5%, the contrast index decreased from 1 to 0.36 when the dose gradient agreement fell from 100% to 10%, and the structure index decreased from 1 to 0.23 when the periodical dose pattern shifted (leading to a lower correlation). Thus, the luminance, contrast and structure index can detect the absolute dose error, gradient discrepancy, and dose structure error, respectively. For the four clinical cases, the sub-indices can reveal the type of error when gamma analysis only provided limited information. CONCLUSIONS: The correlation between the subcomponents of the SSIM index and the error types of the dose distribution were established. The SSIM index provides additional error information compared to that provided by gamma analysis.

8.
J Cell Mol Med ; 24(1): 260-275, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31660692

RESUMO

The vulnerable plaque is a key distinguishing feature of atherosclerotic lesions that can cause acute atherothrombotic vascular disease. This study was designed to explore the effect of autophagy on mitochondria-mediated macrophage apoptosis and vulnerable plaques. Here, we generated the mouse model of vulnerable carotid plaque in ApoE-/- mice. Application of ApoE-/- mice with rapamycin (an autophagy inducer) inhibited necrotic core formation in vulnerable plaques by decreasing macrophage apoptosis. However, 3-methyladenine (an autophagy inhibitor) promoted plaque vulnerability through deteriorating these indexes. To further explore the mechanism of autophagy on macrophage apoptosis, we used macrophage apoptosis model in vitro and found that 7-ketocholesterol (7-KC, one of the primary oxysterols in oxLDL) caused macrophage apoptosis with concomitant impairment of mitochondria, characterized by the impairment of mitochondrial ultrastructure, cytochrome c release, mitochondrial potential dissipation, mitochondrial fragmentation, excessive ROS generation and both caspase-9 and caspase-3 activation. Interestingly, such mitochondrial apoptotic responses were ameliorated by autophagy activator, but exacerbated by autophagy inhibitor. Finally, we found that MAPK-NF-κB signalling pathway was involved in autophagy modulation of 7-KC-induced macrophage apoptosis. So, we provide strong evidence for the potential therapeutic benefit of macrophage autophagy in regulating mitochondria-mediated apoptosis and inhibiting necrotic core formation in vulnerable plaques.

9.
Clin Chim Acta ; 500: 34-41, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31655054

RESUMO

BACKGROUND: Several international staging or scoring systems don't accurately predict overall survival (OS) after resection of primary hepatocellular carcinoma (PHCC). Therefore, we attempted to overcome this limitation by constructing the A-index and its associated nomogram. METHODS: We selected 672 patients who underwent curative resection of PHCC between January 2007 and February 2015 at the first affiliated hospital of the Wenzhou medical university. These subjects were randomly divided into the training (n = 470) and the validation group (n = 202) according to the ratio of 7:3. RESULTS: We prepared the nomogram using eight independent risk factors including the A-index (calculated by 100 × aspartate transaminase /albumin /albumin) in the training cohort. The concordance index (C-index) of the nomogram for both training and validation set was similar in indicating the OS rate. The nomogram showed the strongest predictive power for the 1-year, 3-year, and 5-year OS, with the area under the ROC curve being 0.8182, 0.7892, and 0.7669, respectively. Correction curves showed consistent performance for both groups, stratification of the Kaplan-Meier curve was significant (P < 0.001), and decision curve analysis (DCA) showed the superiority of nomograms considering clinical effects. CONCLUSIONS: The predictive power of the nomogram integrating the A-index for OS was optimal.

10.
Med Phys ; 47(3): 1229-1237, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31856302

RESUMO

PURPOSE: Continuous monitoring of patient movement is crucial to administering safe radiation therapy (RT). Conventional optical approaches often cannot be used when the patient's surface is blocked by immobilization devices. Millimeter waves (mmWaves) are capable of penetrating nonconductive objects. In this study, we investigated using mmWave technology to monitor patient surface displacements, as well as breathing and cardiac phases, through clothing and body fixtures. METHODS: A mmWave device was mounted inside the bore of a ring-based radiotherapy linear accelerator and pointed at a reflective surface on top of the couch. Measurements were obtained at displacements of 10, 7.5, 5.0, 2.5, and 1.0 mm at heights 100, 150, and 200 mm below isocenter. Submillimeter displacements were performed at a height of 200 mm. Additionally, millimeter and submillimeter displacements were measured with and without a gown and body mold placed between the surface and the sensor. The device was programmed to transmit chirp signals at 77-81 GHz. The subject's surface was detected by fast Fourier transform (FFT) of the reflected chirp signal within a rough range bin. Fine displacements within that range bin were calculated through phase extraction and phase demodulation. The displacement data were sent through two separate bandpass filters with passbands of 0.1-0.6 and 0.8-2.0 Hz to obtain the subject's breathing and cardiac waveforms, respectively. The breathing and cardiac measurements were compared to those of a Vernier Respiration Monitor Belt and an electrocardiogram (EKG), respectively, to assess validity. RESULTS: The device was able to detect millimeter and submillimeter displacements as small as 0.1 mm, as well as monitor displacement with an accuracy within 1 mm in the presence of an obstructive object. The device's breathing and cardiac waveforms exhibited a strong phase correlation between the respiration monitor belt (ρ = 0.9156) and EKG (ρ = 0.7895), respectively. CONCLUSIONS: The mmWave device can monitor surface displacements with an accuracy better than 0.1 mm without obstructions and better than 1 mm with obstructions. It can also provide real-time monitoring of breathing and cardiac waveforms simultaneously with high correlation with traditional respiratory and cardiac monitoring devices. Overall, mmWave technology demonstrates potential for motion monitoring in the field of radiation oncology.

11.
Med Phys ; 47(3): 948-957, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31885088

RESUMO

PURPOSE: To characterize the dosimetric features and limitations of the dynamic beam flattening (DBF) on the Halcyon 2.0 linear accelerator (Varian Medical Systems). METHODS: A predefined multi-leaf collimator (MLC) sequence was introduced and used to flatten the 6 MV flattening filter free (FFF) beam on the Halcyon 2.0. Dosimetric characterizations of the flattened beams, including beam flatness, symmetry, percent depth dose (PDD), output factor and MU linearity, were investigated. Flatness and symmetry were obtained from profile measurements with both radiographic films (EDR2) and a two dimensional ion-chamber array (IC Profiler, Sun Nuclear Corporation). MU linearity, output factors, and PDDs were measured in a water tank with a CC13 ion chamber (Scanditronix Wellhöfer, Nuremburg, Germany). In addition, the effect of the DBF sequence on 3D plan quality was evaluated by creating DBF plans for a 4-field box rectum and an AP/PA spine plan. Patient specific QA was performed on these plans. RESULTS: At 100 cm SSD and 10 cm depth, a flatness of <3% was observed on both transversal and radial profiles for all square field sizes ≥10 cm with DBF. For both larger and smaller field sizes the flatness showed a tendency to increase as the fields got bigger or smaller, respectively. Similar trends in flatness were observed at all depths measured. All measured output factors for square field sizes ≥5 cm were within 1% of the TPS prediction. Linearity was ≤2.02% for all measurements. For both treatment sites, the MD judged the plans created for the Halcyon without the use of DBF not to be clinically acceptable, however considered both the TrueBeam plan and the Halcyon plan with the DBF sequence to be clinically acceptable. CONCLUSIONS: The DBF sequence on the Halcyon and its characteristics were investigated. The analysis indicates that the DBF sequence can be used on the Halcyon to generate clinically acceptable 3D treatment plans.

12.
J Oral Rehabil ; 47(1): 1-8, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31378989

RESUMO

BACKGROUND: Oro-facial function is usually impaired by temporomandibular disorders (TMDs). Several studies on TMDs have used the Jaw Functional Limitation Scale (JFLS) to assess mandibular dysfunction. However, it was originally created in English and hence needs to be validated for use among Chinese people. OBJECTIVE: To develop a Chinese version of the JFLS for Chinese TMD patients and to investigate the validity and reliability of the scale. METHODS: Content validity and temporal stability were evaluated at two different occasions. The reliability and validity of the JFLS were tested in 483 TMD patients. Cronbach's alpha coefficient and split-half reliability were used to assess internal consistency, while the validity was evaluated by factor analysis. RESULTS: Three factors were extracted during exploratory factor analysis, accounting for 62.39% of the variance. The three-factor model was then measured using confirmatory factor analysis (χ2 /df = 3.6, root mean square error of approximation = 0.091, comparative fit index = 0.896). Internal (coefficient alpha values of .906 for all items and Guttman split-half reliability of 0.756) and test-retest (intra-class correlation coefficient = .851-.897, 95% confidence interval = 0.656-0.950) reliabilities were excellent. CONCLUSION: The Chinese version of the JFLS is reliable and valid for use in Chinese TMD patients.


Assuntos
Transtornos da Articulação Temporomandibular , Humanos , Arcada Osseodentária , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários
13.
Am J Orthod Dentofacial Orthop ; 156(5): 641-652, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31677673

RESUMO

INTRODUCTION: Studies concerning the visual attention of laypersons viewing the soft tissue facial profile of men and women with malocclusion are lacking. This study aimed to determine the visual attention to the facial profile of patients with different levels of mandibular protrusion and facial background attractiveness using an eye-tracking device. METHODS: The scanning paths of 54 Chinese laypersons (50% female, 50% male, aged 18-23 years) were recorded by an eye-tracking device when they observed composite female facial profile images (n = 24), which were combinations of different degrees of mandibular protrusion (normal, slight, moderate, and severe) and different levels of facial background attractiveness (attractive, average, and unattractive). Dependent variables (fixation duration and first fixation time) were analyzed using repeated-measures factorial analysis of variance. RESULTS: For normal mandibular profiles, the fixation duration of the eyes was significantly higher than that of other facial features (P <0.001). The lower face and nose received the least attention. As the degree of protrusion increased from slight to moderate, more attention was drawn to the lower face accompanied by less attention to eyes in the unattractive group (P <0.05). When protrusion degree increased from moderate to severe, attention shifted from nose to lower face significantly in the attractive group (P <0.05). Attention shift from eyes to lower face was also found in the average group when protrusion degree rose to moderate protrusion from normal profile (P <0.05). A significant interaction between facial attractiveness and mandibular protrusion was found in the lower face duration (P = 0.020). The threshold point (the point of mandibular protrusion degree that evoked attention to the lower face) of the attractive facial background was higher than that of the unattractive background. Once evoked, the effect of mandibular protrusion of the attractive group tended to be stronger than that of the unattractive group, though without statistical difference. CONCLUSIONS: Eyes are the most salient area. The increasing degree of mandibular protrusion tends to draw attention to the lower face from other facial features. Background attractiveness can modify this behavior.


Assuntos
Beleza , Estética Dentária , Movimentos Oculares , Má Oclusão , Adolescente , Olho , Face , Feminino , Humanos , Masculino , Mandíbula , Adulto Jovem
14.
Theranostics ; 9(26): 8196-8205, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31754390

RESUMO

Rationale: Spatial-temporal control of cell fate in vivo is of great importance for regenerative medicine. Currently, there remain no practical strategies to tune cell-fate spatial-temporally. Optogenetics is a biological technique that widely used to control cell activity in genetically defined neurons in a spatiotemporal-specific manner by light. In this study, optogenetics was repurposed for precise bone tissue regeneration. Methods: Lhx8 and BMP2 genes, which are considered as the master genes for mesenchymal stem cell proliferation and differentiation respectively, were recombined into a customized optogenetic control system. In the system, Lhx8 was constitutively expressed, while BMP2 together with shLhx8 expression was driven by blue light. Results: As expected, blue light induced BMP2 expression and inactivated Lhx8 expression in cells infected with the optogenetic control system. Optogenetic control of BMP2 and Lhx8 expression inversely regulates MSC fate in vitro. By animal study, we found that blue light could fine-tune the regeneration in vivo. Blue light illumination significantly promotes bone regeneration when the scaffold was loaded with MSCs infected with adeno-Lhx8, GI-Gal4DBD, LOV-VP16, and BMP2-shLhx8. Conclusions: Together, our study revealed that optogenetic control of the master genes for mesenchymal stem cell proliferation and differentiation would be such a candidate strategy for precise regenerative medicine.

15.
J Am Chem Soc ; 141(50): 19700-19707, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31747277

RESUMO

Perovskite solar cells (PSCs) has skyrocketed in the past decade to an unprecedented level due to their outstanding photoelectric properties and facile processability. However, the utilization of expensive hole transport materials (HTMs) and the inevitable instability instigated by the deliquescent dopants represent major concerns hindering further commercialization. Here, a series of low-cost, conjugated polymers are designed and applied as dopant-free HTMs in PSCs, featuring tuned energy levels, good temperature and humidity resistivity, and excellent photoelectric properties. Further studies highlight the critical and multifaceted roles of the polymers with respect to facilitating charge separation, passivating the surface trap sites of perovskite materials, and guaranteeing long-term stability of the devices. A stabilized power conversion efficiency (PCE) of 20.3% and remarkably enhanced device longevity are achieved using the dopant-free polymer P3 with a low concentration of 5 mg/mL, qualifying the device as one of the best PSC systems constructed on the basis of dopant-free HTMs so far. In addition, the flexible PSCs based on P3 also exhibit a PCE of 16.2%. This work demonstrates a promising route toward commercially viable, stable, and efficient PSCs.

16.
J Appl Clin Med Phys ; 20(11): 14-26, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31617671

RESUMO

BACKGROUND: This study intends to develop an efficient field-in-field (FiF) planning technique with the Eclipse treatment planning system (TPS) to determine the feasibility of using the Halcyon treatment delivery system for 3D treatment of breast cancer. METHODS: Ten treatment plans were prepared on the Halcyon treatment planning system and compared to the same patients' clinically delivered TrueBeam plans which used flattened 6 MV and 10 MV beams. Patients selected for this study were treated via simple, tangential breast irradiation and did not receive radiotherapy of the supraclavicular or internal mammary lymph nodes. Planning target volumes (PTV) volumes ranged from 519 cc to 1211 cc with a mean target volume of 877 cc. Several planning techniques involving collimator, gantry rotation, and number of FiF segments were investigated as well as the use of the dynamically flattened beam (DFB) - a predefined MLC pattern that is designed to provide a flattened beam profile at 10 cm depth on a standard water phantom. For comparison, the clinically delivered TrueBeam plans remained unaltered except for normalization of the target coverage to more readily compare the two treatment delivery techniques. RESULTS: Using the physician defined PTV, normalized such that 98% of the volume was covered by 95% of the prescribed dose, the Halcyon plans were deemed clinically acceptable and comparable to the TrueBeam plans by the radiation oncologist. Resulting average global maximum doses in the test patients were identical between the TrueBeam and Halcyon plans (108% of Rx) and a mean PTV dose of 102.5% vs 101.6%, respectively. CONCLUSIONS: From this study a practical and efficient planning method for delivering 3D conformal breast radiotherapy using the Halcyon linear accelerator has been developed. When normalized to the clinically desired coverage, hot spots were maintained to acceptable levels and overall plan quality was comparable to plans delivered on conventional C-arm LINACs.

17.
Sci Rep ; 9(1): 12940, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31506483

RESUMO

Kavain, a compound derived from Piper methysticum, has demonstrated anti-inflammatory properties. To optimize its drug properties, identification and development of new kavain-derived compounds was undertaken. A focused library of analogs was synthesized and their effects on Porphyromonas gingivalis (P. gingivalis) elicited inflammation were evaluated in vitro and in vivo. The library contained cyclohexenones (5,5-dimethyl substituted cyclohexenones) substituted with a benzoate derivative at the 3-position of the cyclohexanone. The most promising analog identifed was a methylated derivative of kavain, Kava-205Me (5,5-dimethyl-3-oxocyclohex-1-en-1-yl 4-methylbenzoate.) In an in vitro assay of anti-inflammatory effects, murine macrophages (BMM) and THP-1 cells were infected with P. gingivalis (MOI = 20:1) and a panel of cytokines were measured. Both cell types treated with Kava-205Me (10 to 200 µg/ml) showed significantly and dose-dependently reduced TNF-α secretion induced by P. gingivalis. In BMM, Kava-205Me also reduced secretion of other cytokines involved in the early phase of inflammation, including IL-12, eotaxin, RANTES, IL-10 and interferon-γ (p < 0.05). In vivo, in an acute model of P. gingivalis-induced calvarial destruction, administration of Kava-205Me significantly improved the rate of healing associated with reduced soft tissue inflammation and osteoclast activation. In an infective arthritis murine model induced by injection of collagen-antibody (ArthriomAb) + P. gingivalis, administration of Kava-205Me was able to reduce efficiently paw swelling and joint destruction. These results highlight the strong anti-inflammatory properties of Kava-205Me and strengthen the interest of testing such compounds in the management of P. gingivalis elicited inflammation, especially in the management of periodontitis.

18.
J Appl Clin Med Phys ; 20(10): 53-66, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31541542

RESUMO

PURPOSE: To present lessons learned from magnetic resonance imaging (MRI) quality control (QC) tests for low-field MRI-guided radiation therapy (MR-IGRT) systems. METHODS: MRI QC programs were established for low-field MRI-60 Co and MRI-Linac systems. A retrospective analysis of MRI subsystem performance covered system commissioning, operations, maintenance, and quality control. Performance issues were classified into three groups: (a) Image noise and artifact; (b) Magnetic field homogeneity and linearity; and (c) System reliability and stability. RESULTS: Image noise and artifacts were attributed to room noise sources, unsatisfactory system cabling, and broken RF receiver coils. Gantry angle-dependent magnetic field inhomogeneities were more prominent on the MRI-Linac due to the high volume of steel shielding in the gantry. B0 inhomogeneities measured in a 24-cm spherical phantom were <5 ppm for both MR-IGRT systems after using MRI gradient offset (MRI-GO) compensation on the MRI-Linac. However, significant signal dephasing occurred on the MRI-Linac while the gantry was rotating. Spatial integrity measurements were sensitive to gradient calibration and vulnerable to shimming. The most common causes of MR-IGRT system interruptions were software disconnects between the MRI and radiation therapy delivery subsystems caused by patient table, gantry, and multi-leaf collimator (MLC) faults. The standard deviation (SD) of the receiver coil signal-to-noise ratio was 1.83 for the MRI-60 Co and 1.53 for the MRI-Linac. The SD of the deviation from the mean for the Larmor frequency was 1.41 ppm for the MRI-60 Co and 1.54 ppm for the MRI-Linac. The SD of the deviation from the mean for the transmitter reference amplitude was 0.90% for the MRI-60 Co and 1.68% for the MRI-Linac. High SDs in image stability data corresponded to reports of spike noise. CONCLUSIONS: There are significant technological challenges associated with implementing and maintaining MR-IGRT systems. Most of the performance issues were identified and resolved during commissioning.

19.
Nanoscale Res Lett ; 14(1): 269, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31392425

RESUMO

In this study, we propose a one-drop self-assembly method, which proved capable of successfully preparing 4-N, N-dimethylamino-4'-N'-methyl-stilbazolium tosylate (DAST) single-crystalline nanowires (NWs). The apparent roughness of the DAST NWs was determined to be less than 100 pm by using a high-resolution atomic force microscope, indicating their ultrafine quality. The DAST NWs also exhibited excellent nonlinear optical properties, including two-photon excited fluorescence and second harmonic generation, which could enable the production of low-cost, low-power-consumption wideband wavelength conversion devices. Thus, the described method may provide a new avenue for organic NW fabrication.

20.
Hum Mutat ; 40(12): 2334-2343, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31373411

RESUMO

Intermediate Charcot-Marie-Tooth (CMT) disease is a heterogeneous group of inherited neuropathies characterized by progressive muscle weakness and atrophy of the distal extremities, distal sensory loss. There were still a large proportion of causative genes for intermediate CMT failed to be identified. Here, using whole-exome sequencing technique, we identified two novel missense mutations in ATP1A1 gene, c.620C>T (p.S207F) and c.2629G>A (p.G877S), in two Chinese CMT families. Further functional analysis revealed that these mutations led to the loss function of the ATP1A1 protein. The two mutations did not affect the levels of messenger RNA but possessed a damaging effect on ATP1A1 protein expression and they downregulated the protein levels of ATP1A1 by promoting its proteasome degradation. Taken together, we confirmed ATP1A1 as a novel causative gene for intermediate CMT.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA