10,717 research outputs found
Treating a maxillary midline diastema in adult patients: A general dentist's perspective
Background: A maxillary midline diastema (MMD) often is a primary concern of patients during a dental consultation. Although an MMD can be transient owing to the developing dentition and, thus, requires no active treatment, management of MMDs in the permanent dentition requires a detailed examination and appropriate care. Case Descriptions: The authors present five cases of MMDs in adults to illustrate a range of restorative and orthodontic options. In the first case, the clinician used resin-based composite buildup to close an MMD resulting from small teeth and generalized spacing in the dental arch. In the second case, the clinician placed porcelain veneers to treat an MMD in a patient with discolored dentition. In the third case, the clinician fitted a removable appliance to close an MMD by tipping the incisors palatally. In the fourth case, the clinician fitted a sectional fixed appliance to promote mesial bodily movement of the incisors. In the fifth case, the clinician placed a full-arch fixed appliance to treat an MMD caused by tilted incisors. Conclusions and Clinical Implications: Effective treatment requires an accurate diagnosis and appropriate intervention. General dentists can perform a range of restorative and orthodontic treatments in appropriate clinical situations to address patients' concerns.link_to_subscribed_fulltex
Chemical Modification of Cellulose with Succinic Anhydride in Ionic Liquid with or without Catalysts
Deep Learning using K-space Based Data Augmentation for Automated Cardiac MR Motion Artefact Detection
Quality assessment of medical images is essential for complete automation of
image processing pipelines. For large population studies such as the UK
Biobank, artefacts such as those caused by heart motion are problematic and
manual identification is tedious and time-consuming. Therefore, there is an
urgent need for automatic image quality assessment techniques. In this paper,
we propose a method to automatically detect the presence of motion-related
artefacts in cardiac magnetic resonance (CMR) images. As this is a highly
imbalanced classification problem (due to the high number of good quality
images compared to the low number of images with motion artefacts), we propose
a novel k-space based training data augmentation approach in order to address
this problem. Our method is based on 3D spatio-temporal Convolutional Neural
Networks, and is able to detect 2D+time short axis images with motion artefacts
in less than 1ms. We test our algorithm on a subset of the UK Biobank dataset
consisting of 3465 CMR images and achieve not only high accuracy in detection
of motion artefacts, but also high precision and recall. We compare our
approach to a range of state-of-the-art quality assessment methods.Comment: Accepted for MICCAI2018 Conferenc
Investigating freeway traffic hypercongestion between an on-ramp and its immediate upstream off-ramp
This paper applies the freeway traffic congestion dynamics proposed in Laval and Leclercq [2010. “Continuum Approximation for Congestion Dynamics Along Freeway Corridors.” Transportation Science 44 (1): 87–97] but with a modified distribution scheme of freeway merging flows to investigation of traffic hypercongestion on a freeway between an on-ramp and its immediate upstream off-ramp. The reason to make this modification is that the original merging scheme of this dynamics is found to possibly give undesired full priority to the traffic from the on-ramp and also occasionally make the resulting flow going through the merge greater than the available capacity. Traffic hypercongestion in this paper refers to a state where speed and flow change in the same direction as density varies. A homogeneous freeway segment chosen for this investigation includes an on-ramp and an off-ramp, which may correspond to a freeway passing by a city or town, with an off-ramp lying upstream towards the city and an on-ramp downstream. The entry flow from the upstream approach of the freeway was fixed and constant within the time horizon while both deterministic and random on-ramp inflow rates were used in this investigation. Then the formation and dissipation of traffic hypercongestion is investigated as on-ramp demand and off-ramp departure profiles vary. The first finding of this investigation is that the density in the hypercongestion area behind the merge never reached the jam density. Second, the hypercongested area continued to grow as long as the sum of the demand from the upstream of the freeway and that from the on-ramp was greater than the available capacity at the merge. Third, as long as the rate of flow leaving from the freeway via the off-ramp was not smaller than the entry flow rates from the on-ramp, no hypercongestion had been observed. In addition, in analysing the numerical results, a series of discussions was carried out to build the linkage between the on- and off-ramp flow profiles and the generated and attracted demand of the city plus its adjacent area the two ramps served for; these discussions suggest that the balanced generated and attracted demand of the city plus its adjacent area can reduce or even remove traffic hypercongestion behind the merge on the chosen freeway segment.postprin
A Fucus vesiculosus extract inhibits estrogen receptor activation and induces cell death in female cancer cell lines.
BACKGROUND: We previously reported the anti-estrogenic activity of the brown seaweed, Fucus vesiculosus. The present study aimed to further investigate its anti-estrogenic modes of action and to assess other potentially biologically relevant anti-tumorigenic effects in estrogen receptor (ER)-dependent and -independent female cancer cell lines. METHODS: The CALUX® assay was used to determine the effect of a F. vesiculosus extract (FVE) on activation of the ER. Aromatase enzymatic activity was measured to determine the potential effect of FVE on estradiol (E2) biosynthesis. Transcriptional activity profiling of 248 genes involved in cancer, immunity, hormonal regulation, protein phosphorylation, transcription, metabolism, and cellular structure was conducted using the NanoString nCounter® analysis system in FVE-treated breast, ovarian and endometrial cancer cell lines. The effects of FVE on cell viability, morphology, membrane integrity, mitochondrial toxicity, induction of apoptotic and autophagic markers, and cell signaling were also analyzed. RESULTS: In co-treatments with 12.5 pM (EC50) E2, FVE (2 %) reduced ER activation by 50 %, exhibiting potent ER antagonistic effects. FVE inhibited aromatase activity in an in vitro assay (IC50 2.0 %). ER-dependent and -independent cancer cell lines showed significantly decreased viability that correlated with increasing FVE concentrations and altered morphological features suggestive of apoptosis and autophagy. Expression of genes that were significantly altered by FVE (p < 0.05) revealed predominantly apoptotic, autophagic and kinase signaling pathways. FVE also effectively inhibited the phosphorylation of Akt, resulting in reduced mTORC1 activities to stimulate autophagy in cells. Concentration-dependent cleavage of PARP and induction of caspase-3 and -7 activities were observed in MDA-MB-231 cells supporting a role for FVE in the promotion of apoptosis. CONCLUSIONS: Our study provides new insights into the anti-estrogenic activity of F. vesiculosus. Moreover, the induction of autophagy and apoptosis on breast, endometrial and ovarian cancer cell lines suggests additional anti-tumorigenic actions of FVE that are independent of ER status in female cancers
MicroRNA-210 and endoplasmic reticulum chaperones in the regulation of chemoresistance in glioblastoma
Glioblastoma multiforme (GBM) is the commonest primary brain tumour in adults characterized by relentless recurrence due to resistance towards the standard chemotherapeutic agent temozolomide (TMZ). Prolyl 4-hydroxylase, beta polypeptide (P4HB), an endoplasmic reticulum (ER) chaperone, is known to be upregulated in TMZ-resistant GBM cells. MicroRNAs (miRNAs) are non-protein-coding transcripts that may play important roles in GBM chemoresistance. We surmised that miRNA dysregulations may contribute to P4HB upregulation, hence chemoresistance.We found that miRNA-210 (miR-210) was P4HB-targeting and was highly downregulated in TMZ-resistant GBM cells. Forced overexpression of miR-210 led to P4HB downregulation and a reduction in TMZ-resistance. A reciprocal relationship between their expressions was also verified in clinical glioma specimens. Our study is the first to demonstrate a potential link between miR-210 and ER chaperone in determining chemosensitivity in GBM. The findings have important translational implications in suggesting new directions of future studies.published_or_final_versio
Infall of gas as the formation mechanism of stars up to 20 times more massive than the Sun
Theory predicts and observations confirm that low-mass stars (like the Sun)
in their early life grow by accreting gas from the surrounding material. But
for stars ~ 10 times more massive than the Sun (~10 M_sun), the powerful
stellar radiation is expected to inhibit accretion and thus limit the growth of
their mass. Clearly, stars with masses >10 M_sun exist, so there must be a way
for them to form. The problem may be solved by non-spherical accretion, which
allows some of the stellar photons to escape along the symmetry axis where the
density is lower. The recent detection of rotating disks and toroids around
very young massive stars has lent support to the idea that high-mass (> 8
M_sun) stars could form in this way. Here we report observations of an ammonia
line towards a high-mass star forming region. We conclude from the data that
the gas is falling inwards towards a very young star of ~20 M_sun, in line with
theoretical predictions of non-spherical accretion.Comment: 11 pages, 2 figure
Self-supervised Contrastive Video-Speech Representation Learning for Ultrasound
In medical imaging, manual annotations can be expensive to acquire and
sometimes infeasible to access, making conventional deep learning-based models
difficult to scale. As a result, it would be beneficial if useful
representations could be derived from raw data without the need for manual
annotations. In this paper, we propose to address the problem of
self-supervised representation learning with multi-modal ultrasound
video-speech raw data. For this case, we assume that there is a high
correlation between the ultrasound video and the corresponding narrative speech
audio of the sonographer. In order to learn meaningful representations, the
model needs to identify such correlation and at the same time understand the
underlying anatomical features. We designed a framework to model the
correspondence between video and audio without any kind of human annotations.
Within this framework, we introduce cross-modal contrastive learning and an
affinity-aware self-paced learning scheme to enhance correlation modelling.
Experimental evaluations on multi-modal fetal ultrasound video and audio show
that the proposed approach is able to learn strong representations and
transfers well to downstream tasks of standard plane detection and eye-gaze
prediction.Comment: MICCAI 2020 (early acceptance
p38 Mapk signal pathway involved in anti-inflammatory effect of chaihu-shugan-san and shen-ling-bai-zhu-san on hepatocyte in non-alcoholic steatohepatitis rats
Background: Traditional Chinese Medicine (TCM), has over thousands-of-years history of use. Chaihu-Shugan-San (CSS), and Shen-ling-bai-zhu-San (SLBZS), are famous traditional Chinese herbal medicine formulas, which have been used in China, for the treatment of many chronic diseases.Materials and Methods:This study investigated the anti-inflammatory effects of CSS and SLBZS on signaling molecules involved in p38 mitogen-activated protein kinase (p38 MAPK), pathway on hepatocytes of non-alcoholic steatohepatitis (NASH), rats induced by high fat diet. SD male rats were randomly divided into 8 groups: negative control group, model control group, high (9.6g/kg/day)/low (3.2g/kg/day)-dose CSS group, high (30g/kg/day)/low (10g/kg/day)-dose SLBZS group, high (39.6g/kg/day)/low (13.2g/kg/day)-dose integrated group. The rats of NASH model were induced by feeding a high-fat diet. After 16, wks, Hepatocytes were isolated from 6, rats in each group by collagenase perfusion. The liver histopathological changes and serum inflammatory cytokines TNF-α, IL-6 were determined. The proteins of TLR4, phosphor-p38 MAPK and p38 MAPK involved in p38 MAPK signal pathway were assayed.Results: The statistical data indicated the NASH model rats reproduced typical histopathological features of NASH in human. CSS and SLBZS ameliorated lipid metabolic disturbance, attenuated NASH progression, decreased the levels of TNF-α and IL-6 in serum, as well as inhibited TLR4 protein expression, p38 MAPK phosphorylation, and activation of p38 MAPK. In conclusion, CSS and SLBZS might work as a significant anti-inflammatory effect on hepatocyte of NASH by inhibiting the activation of TLR4, p-p38 MAPK and p38 MAPK involved in p38 MAPK signal pathway.Conclusion: To some extent, CSS and SLBZS may be a potential alternative and complementary medicine to protect against liver injury, alleviate the inflammation reaction, moderate NASH progression.Key words: p38 mitogen-activated protein kinase; Toll like receptor 4; Hepatocytes; Non-alcoholic Steatohepatitis; Traditional Chinese medicine
- …