1,282 research outputs found
Role of tissue factor pathway inhibitor-2 in the expressions of matrix metallopro- teinases in keratocytes in vitro
AIM:To elucidate the relation between tissue factor pathway inhibitor-2(TFPI-2)expression and the expression of matrix metalloproteinases(MMPs)in keratocytes. METHODS: Primary culture and subculture of rabbit keratocytes were established in vitro. Plasmid vector pBos-Cite-neo/TFPI-2 was transfected into keratocytes with Lipofectamine 2000. After being selected by G418, three groups of cells including TFPI-2 gene transfected cells K-TFPI-2, empty vector transfected cells K-V and non-transfected cells K-P were screened for TFPI-2 mRNA and protein by reverse transcription-polymerase chain reaction and Western blot analysis, respectively. The activity of MMPs in the three groups of cells was detected by substrate zymography and compared by ANOVA. RESULTS: Expression of mRNA and protein of TFPI-2 was more in the cells of K-TFPI-2 than in the other cells of K-P and K-V with a significant difference(mRNA:0.79±0.02 vs 0.51±0.03 and 0.48±0.02, P=0.000 and P=0.000; Protein:24.5±0.8 vs 15.5±0.5 and 14.9±0.9,P=0.000 and P=0.000). Compared with the two groups of K-P and K-V, the cells of K-TFPI-2 had a significant decreased activity of MMP1(12.3±0.7 vs 16.7±1.2 and 15.9±0.7, P=0.001 and P=0.003)and MMP2(15.4±1.3 vs 18.2±1.1 and 17.8±1.1, P=0.027 and P=0.046). CONCLUSION: It is suggested that the expression of TFPI-2 may strongly inhibit the activity of MMPs in keratocytes in vitro, which provides an experimental basis for curing CNV with gene therapy
Glueball Masses from Hamiltonian Lattice QCD
We calculate the masses of the , and glueballs from
QCD in 3+1 dimensions using an eigenvalue equation method for Hamiltonian
lattice QCD developed and described elsewhere by the authors. The mass ratios
become approximately constants in the coupling region ,
from which we estimate and
.Comment: 12 pages, Latex, figures to be sent upon reques
Advancing Radiograph Representation Learning with Masked Record Modeling
Modern studies in radiograph representation learning rely on either
self-supervision to encode invariant semantics or associated radiology reports
to incorporate medical expertise, while the complementarity between them is
barely noticed. To explore this, we formulate the self- and report-completion
as two complementary objectives and present a unified framework based on masked
record modeling (MRM). In practice, MRM reconstructs masked image patches and
masked report tokens following a multi-task scheme to learn knowledge-enhanced
semantic representations. With MRM pre-training, we obtain pre-trained models
that can be well transferred to various radiography tasks. Specifically, we
find that MRM offers superior performance in label-efficient fine-tuning. For
instance, MRM achieves 88.5% mean AUC on CheXpert using 1% labeled data,
outperforming previous RL methods with 100% labels. On NIH ChestX-ray, MRM
outperforms the best performing counterpart by about 3% under small labeling
ratios. Besides, MRM surpasses self- and report-supervised pre-training in
identifying the pneumonia type and the pneumothorax area, sometimes by large
margins.Comment: Camera ready at ICLR 2023. Code and models are available at
https://github.com/RL4M/MRM-pytorc
Effects of synthetic colloids on oxidative stress and inflammatory response in hemorrhagic shock: comparison of hydroxyethyl starch 130/0.4, hydroxyethyl starch 200/0.5, and succinylated gelatin
INTRODUCTION: This study compared the effects of hydroxyethyl starch 130/0.4, hydroxyethyl starch 200/0.5, and succinylated gelatin on oxidative stress and the inflammatory response in a rodent hemorrhagic shock model. METHODS: Sodium pentobarbital-anesthetized adult male Wistar rats (200 g to 220 g) were subjected to a severe volume-controlled hemorrhage using arterial blood withdrawal (30 mL/kg to 33 mL/kg) and resuscitated with a colloid solution at the same volume as blood withdrawal (hydroxyethyl starch 130/0.4, hydroxyethyl starch 200/0.5, or succinylated gelatin). Arterial blood gas parameters were monitored. Malondialdehyde (MDA) content and myeloperoxidase (MPO) activity in the liver, lungs, intestine, and brain were measured two hours after resuscitation. The levels of tumor necrosis factor-alpha (TNF-α) and interleukin-6 in the intestine were also measured. RESULTS: Infusions of hydroxyethyl starch 130/0.4, but not hydroxyethyl starch 200/0.5 or succinylated gelatin, significantly reduced MDA levels and MPO activity in the liver, intestine, lungs and brain, and it also inhibited the production of TNF-α in the intestine two hours after resuscitation. However, no significant difference between hydroxyethyl starch 200/0.5 and succinylated gelatin was observed. CONCLUSIONS: Hydroxyethyl starch 130/0.4, but not hydroxyethyl starch 200/0.5 or succinylated gelatin, treatment after hemorrhagic shock ameliorated oxidative stress and the inflammatory response in this rat model. No significant differences were observed after hydroxyethyl starch 200/0.5 or succinylated gelatin administration at doses of approximately 33 mL/kg
Lithofacies paleogeography mapping and reservoir prediction in tight sandstone strata: A case study from central Sichuan Basin, China
AbstractSand-rich tight sandstone reservoirs are potential areas for oil and gas exploration. However, the high ratio of sandstone thickness to that of the strata in the formation poses many challenges and uncertainties to traditional lithofacies paleogeography mapping. Therefore, the prediction of reservoir sweet spots has remained problematic in the field of petroleum exploration. This study provides new insight into resolving this problem, based on the analyses of depositional characteristics of a typical modern sand-rich formation in a shallow braided river delta of the central Sichuan Basin, China. The varieties of sand-rich strata in the braided river delta environment include primary braided channels, secondary distributary channels and the distribution of sediments is controlled by the successive superposed strata deposited in paleogeomorphic valleys. The primary distributary channels have stronger hydrodynamic forces with higher proportions of coarse sand deposits than the secondary distributary channels. Therefore, lithofacies paleogeography mapping is controlled by the geomorphology, valley locations, and the migration of channels. We reconstructed the paleogeomorphology and valley systems that existed prior to the deposition of the Xujiahe Formation. Following this, rock-electro identification model for coarse skeletal sand bodies was constructed based on coring data. The results suggest that skeletal sand bodies in primary distributary channels occur mainly in the valleys and low-lying areas, whereas secondary distributary channels and fine deposits generally occur in the highland areas. The thickness distribution of skeletal sand bodies and lithofacies paleogeography map indicate a positive correlation in primary distributary channels and reservoir thickness. A significant correlation exists between different sedimentary facies and petrophysical properties. In addition, the degree of reservoir development in different sedimentary facies indicates that the mapping method reliably predicts the distribution of sweet spots. The application and understanding of the mapping method provide a reference for exploring tight sandstone reservoirs on a regional basis
EFFECTS OF LONG-TERM TAI CHI EXERCISE ON BALANCE CONTROL IN OLDER ADULTS
This study assessed the static and dynamic balance control of older adults who have 10 years of Tai Chi exercise experience and compared their characteristics with their sedentary counterparts. The abilities were measured using methods: single-leg stance times with eyes open and closed; sway of center of pressure (COP) during static standing with eyes open/closed, and leaning the body in three specific directions. Compared with control group, 1) Tai Chi Group showed longer single-leg stance times with eyes open and closed, 2) slower sway velocity of COP in mediolateral and anterioposterior directions and shorter sway distance in both directions, and 3) shorter total, anterioposterior, and mediolateral routes and shorter time spent during the dynamic balance test. Long-term Tai Chi exercise improves the balance ability, especially the dynamic balance, of older adults
Alternative O-GlcNAcylation/O-Phosphorylation of Ser16 Induce Different Conformational Disturbances to the N Terminus of Murine Estrogen Receptor β
SummarySerine and threonine residues in many proteins can be modified by either phosphorylation or GlcNAcylation. To investigate the mechanism of O-GlcNAc and O-phosphate's reciprocal roles in modulating the degradation and activity of murine estrogen receptor β (mER-β), the conformational changes induced by O-GlcNAcylation and O-phosphorylation of Ser16 in 17-mer model peptides corresponding to the N-terminal intrinsically disordered (ID) region of mER-β were studied by NMR techniques, circular dichroism (CD), and molecular dynamics simulations. Our results suggest that O-phosphorylation discourages the turn formation in the S15STG18 fragment. In contrast, O-GlcNAcylation promotes turn formation in this region. Thus, we postulate that the different changes of the local structure in the N-terminal S15STG18 fragment of mER-β caused by O-phosphate or O-GlcNAc modification might lead to the disturbances to the dynamic ensembles of the ID region of mER-β, which is related to its modulatory activity
Distinguishing Smilax glabra and Smilax china rhizomes by flow-injection mass spectrometry combined with principal component analysis
Flow-injection mass spectrometry (FIMS) coupled with a chemometric method is proposed in this study to profile and distinguish between rhizomes of Smilax glabra (S. glabra) and Smilax china (S. china). The proposed method employed an electrospray-time-of-flight MS. The MS fingerprints were analyzed using principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) with the aid of SIMCA software. Findings showed that the two kinds of samples perfectly fell into their own classes. Further predictive study showed desirable predictability and the tested samples were successfully and reliably identified. The study demonstrated that the proposed method could serve as a powerful tool for distinguishing between S. glabra and S. china
Upconversion NIR-II fluorophores for mitochondria-targeted cancer imaging and photothermal therapy
Acknowledgements: The work was supported by the National Key R&D Program of China (2020YFA0908800), NSFC (81773674, 81573383), Shenzhen Science and Technology Research Grant (JCYJ20190808152019182), Hubei Province Scientific and Technical Innovation Key Project, National Natural Science Foundation of Hubei Province (2017CFA024, 2017CFB711), the Applied Basic Research Program of Wuhan Municipal Bureau of Science and Technology (2019020701011429), Tibet Autonomous Region Science and Technology Plan Project Key Project (XZ201901-GB-11), the Local Development Funds of Science and Technology Department of Tibet (XZ202001YD0028C), Project First-Class Disciplines Development Supported by Chengdu University of Traditional Chinese Medicine (CZYJC1903), Health Commission of Hubei Province Scientific Research Project (WJ2019M177, WJ2019M178), the China Scholarship Council, and the Fundamental Research Funds for the Central Universities.Peer reviewedPublisher PD
INTENTION TO USE VIRTUAL REALITY IN SARAWAK TOURISM DESTINATIONS: A TEST OF STIMULUS-ORGANISM-RESPONSE (S-O-R) MODEL
The industry of tourism in Malaysia is highly recognized for its contribution to the national economy and employment
opportunities. However, following the strike of global epidemic due to COVID-19, the number of visitations by tourists has
plunged and Malaysia is currently in its stage of revitalizing the industry post-COVID-19. To rejuvenate the tourism industry of
Sarawak, Malaysia, the understanding of motivators to boost favourable tourists’ behaviours is crucial, given the ever-changing
situation in the tourism market. This study explored the relationship between dimensions of Stimulus-Organism-Response (S-OR) model, particularly in tourism destinations of Sarawak with the adoption of Virtual Reality (VR) technology. The survey was
participated by 250 tourists and the proposed model was evaluated using WarpPLS 8.0. The statistical findings revealed the
significant positive relationships between all tested constructs (i.e., media richness, presence, utilitarian and hedonic value,
behavioural and visit intention). The implications of these findings are further discussed
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