1,523 research outputs found
BBR-induced Stark shifts and level broadening in helium atom
The precise calculations of blackbody radiation (BBR)-induced Stark shifts
and depopulation rates for low-lying states of helium atom with the use of
variational approach are presented. An effect of the BBR-induced induced
Stark-mixing of energy levels is considered. It is shown that this effect leads
to a significant reduction of lifetimes of helium excited states. As a
consequence the influence of Stark-mixing effect on the decay rates of
metastable states in helium is discussed in context of formation processes of
the cosmic microwave background
In vitro angiogenesis and expression of nuclear factor ÎșB and VEGF in high and low metastasis cell lines of salivary gland Adenoid Cystic Carcinoma
<p>Abstract</p> <p>Background</p> <p>Adenoid cystic carcinoma is a high malignant carcinoma characterized by intensive local invasion and high incidence of distant metastasis. Although many reports have demonstrated that angiogenesis has played an important role in tumor metastasis, the relationship between metastasis characters and angiogenesis ability in high and low metastasis cell lines of Adenoid cystic carcinoma has rarely been reported. The present study aimed to compare the angiogenesis ability of ACC-M (high metastasis) and ACC-2 (low metastasis) cell lines in vitro. Furthermore, the activity of nuclear factor Îșappa B and the expression of vascular endothelial growth factor (VEGF) in ACC-2 and ACC-M were also detected.</p> <p>Methods</p> <p>Electrophoretic mobility shift assay was used to detect nuclear factor Îșappa B activity. Semi-quantitative RT-PCR was used to quantify the mRNA level of VEGF. Immuofluorescence double staining and semi-quantitative confocal laser scanning analysis was carried out to detect nuclear factor Îșappa B nuclear localization and staining intensity of VEGF. The angiogenesis ability of ACC-M and ACC-2 was compared by an in vitro three-dimensional angiogenic model assay. The vector transfection assay was performed to transfect the PCMV-IÎșBαM vector into ACCs cell lines expressing the phosphorylation defective IÎșBαM.</p> <p>Results</p> <p>Nuclear factor Îșappa B activity and the rate of nuclear factor Îșappa B nuclear localization in ACC-M was significantly higher than that in ACC-2. Moreover, ACC-M exhibited higher mRNA and protein levels of vascular endothelial growth factor than ACC-2. VEGF mRNA expression was effectively decreased by inhibition of nuclear factor Îșappa B activity. Furthermore, ACC-M could remarkably stimulate the migration and tube formation of endothelial cells and induce The umbilical vein endothelial cells sprouting into the gel matrix.</p> <p>Conclusion</p> <p>These results implicated that ACCs cells with higher metastasis feature might present greater angiogenesis ability.</p
HIPK2 reduces the resistance of gastric cancer cells to cisplatin via p53 pathway
Purpose: To uncover the functional effect of homologous domain-associated protein kinase 2 (HIPK2) on the viability of cisplatin (DDP)-resistant gastric cancer (GC) cells and elucidate the possible mechanism of action.Methods: The effect of DDP on GC viability and apoptotic rate was evaluated using MTT and flow cytometry (FCM) assays. The potential effect of HIPK2 on DDP sensitivity and cell apoptosis was investigated in the presence of cisplatin while the effect of HIPK2 on p53 activation was determined by immunoblot assay.Results: HIPK2 expression was decreased in DDP-resistant GC cell while upregulation of HIPK2 reduced growth, but promoted apoptosis in DDP-resistant GC cells. Further investigations showed that HIPK2 promoted p53 activation, while suppression of p53 weakened the inhibitory effect of HIPK2 on DDP-resistance in GC cells.Conclusion: The results suggest that HIPK2 is a promising and important therapeutic factor for the regulation of the resistance of GC cells to DDP. Thus, may have a role to play in the management of gastric cancer
Keywords: Gastric cancer, Cisplatin, HIPK2, Homologous domain-associated protein kinase 2, p53 pathway, Therapeutic targe
Recommended from our members
Heterogeneity in Host Risk Factors for Incident Melanoma and Non-Melanoma Skin Cancer in a Cohort of US Women
Background: Melanoma, squamous cell carcinoma (SCC), and basal cell carcinoma (BCC) are 3 types of skin cancer that have distinct biologic characteristics and prognoses. We evaluated phenotypic differences in the risk of these cancers in US women. Methods: We conducted a prospective study of 113 139 female nurses from 1984 to 2002. Over the 18 years of follow-up, there were 375 cases of melanoma, 495 cases of SCC, and 9423 cases of BCC. Results: Women with melanoma were more likely to have a family history of melanoma (melanoma: RR 1.94, 95% confidence interval [CI] 1.36â2.76; SCC: RR 0.82, 95% CI 0.58â1.37; BCC: RR 1.49, 95% CI 1.38â1.62) and 6 or more moles on the left arm (melanoma: RR 3.66, 95% CI 2.15â6.24; SCC: RR 1.53, 95% CI 0.83â2.79; BCC: RR 1.48, 95% CI 1.28â1.72). Polytomous logistic regression analysis showed that age at diagnosis (P < 0.0001), family history of melanoma (P = 0.016), and number of moles on the left arm (P = 0.007) were significantly different across the 3 cancers. Conclusions: This prospective observational study demonstrated that known phenotypic factors for skin cancer have a differential impact on the risk of melanoma, SCC, and BCC
Government regulation of emergency supplies under the epidemic crisis
This paper constructs a multi-oligopoly model of emergency supplies and analyses the market equilibrium results under normal
conditions and epidemic conditions. The impacts of the degree of
change in market demand, externalities, the material cost of
emergency supplies and government regulation on the equilibrium results, especially on the prices of emergency supplies, are
discussed. The results show that an increase in material cost will
lead to low output and social welfare and a high price, under
either normal conditions or epidemic conditions. Moreover, under
epidemic conditions, the degree of change in market demand,
externalities, material cost and the presence and mode of government regulation all have multiple and complex influences on the
equilibrium results. Under epidemic conditions, both government
output and price regulation can increase the supply of emergency
supplies. In addition, when market demand changes drastically,
consumer surplus and social welfare can be enhanced by the
implementation of regulations. Particularly, price regulation is
more effective when there is a high material cost
Deep Dictionary Learning with An Intra-class Constraint
In recent years, deep dictionary learning (DDL)has attracted a great amount
of attention due to its effectiveness for representation learning and visual
recognition.~However, most existing methods focus on unsupervised deep
dictionary learning, failing to further explore the category information.~To
make full use of the category information of different samples, we propose a
novel deep dictionary learning model with an intra-class constraint (DDLIC) for
visual classification. Specifically, we design the intra-class compactness
constraint on the intermediate representation at different levels to encourage
the intra-class representations to be closer to each other, and eventually the
learned representation becomes more discriminative.~Unlike the traditional DDL
methods, during the classification stage, our DDLIC performs a layer-wise
greedy optimization in a similar way to the training stage. Experimental
results on four image datasets show that our method is superior to the
state-of-the-art methods.Comment: 6 pages, 3 figures, 2 tables. It has been accepted in ICME202
Recommended from our members
Oscillation-specific nodal alterations in early to middle stages Parkinsons disease.
Background: Different oscillations of brain networks could carry different dimensions of brain integration. We aimed to investigate oscillation-specific nodal alterations in patients with Parkinsons disease (PD) across early stage to middle stage by using graph theory-based analysis. Methods: Eighty-eight PD patients including 39 PD patients in the early stage (EPD) and 49 patients in the middle stage (MPD) and 36 controls were recruited in the present study. Graph theory-based network analyses from three oscillation frequencies (slow-5: 0.01-0.027âHz; slow-4: 0.027-0.073âHz; slow-3: 0.073-0.198âHz) were analyzed. Nodal metrics (e.g. nodal degree centrality, betweenness centrality and nodal efficiency) were calculated. Results: Our results showed that (1) a divergent effect of oscillation frequencies on nodal metrics, especially on nodal degree centrality and nodal efficiency, that the anteroventral neocortex and subcortex had high nodal metrics within low oscillation frequencies while the posterolateral neocortex had high values within the relative high oscillation frequency was observed, which visually showed that network was perturbed in PD; (2) PD patients in early stage relatively preserved nodal properties while MPD patients showed widespread abnormalities, which was consistently detected within all three oscillation frequencies; (3) the involvement of basal ganglia could be specifically observed within slow-5 oscillation frequency in MPD patients; (4) logistic regression and receiver operating characteristic curve analyses demonstrated that some of those oscillation-specific nodal alterations had the ability to well discriminate PD patients from controls or MPD from EPD patients at the individual level; (5) occipital disruption within high frequency (slow-3) made a significant influence on motor impairment which was dominated by akinesia and rigidity. Conclusions: Coupling various oscillations could provide potentially useful information for large-scale network and progressive oscillation-specific nodal alterations were observed in PD patients across early to middle stages
- âŠ