125 research outputs found
A Generalization of ViT/MLP-Mixer to Graphs
Graph Neural Networks (GNNs) have shown great potential in the field of graph
representation learning. Standard GNNs define a local message-passing mechanism
which propagates information over the whole graph domain by stacking multiple
layers. This paradigm suffers from two major limitations, over-squashing and
poor long-range dependencies, that can be solved using global attention but
significantly increases the computational cost to quadratic complexity. In this
work, we propose an alternative approach to overcome these structural
limitations by leveraging the ViT/MLP-Mixer architectures introduced in
computer vision. We introduce a new class of GNNs, called Graph MLP-Mixer, that
holds three key properties. First, they capture long-range dependency and
mitigate the issue of over-squashing as demonstrated on the Long Range Graph
Benchmark (LRGB) and the TreeNeighbourMatch datasets. Second, they offer better
speed and memory efficiency with a complexity linear to the number of nodes and
edges, surpassing the related Graph Transformer and expressive GNN models.
Third, they show high expressivity in terms of graph isomorphism as they can
distinguish at least 3-WL non-isomorphic graphs. We test our architecture on 4
simulated datasets and 7 real-world benchmarks, and show highly competitive
results on all of them
Surgical Models of Gastroesophageal Reflux with Mice
Multiple surgical procedures have been reported to induce gastroesophageal reflux in animals. Herein, we report three surgical models with mice aiming to induce reflux of gastric contents, duodenal contents or mixed contents. Surgical procedures and general principles have been described in detail. A researcher with surgical experience should be able to grasp the technique after a short period of practice. After surgery, most mice can survive and develop reflux esophagitis similar to that in humans. However, it should be noted that histological differences between mouse and human esophagus are the inherent limitations of these surgical models. If used for research on Barrett’s esophagus and adenocarcinoma, these procedures may need to be combined with genetic modifications
Harnessing Explanations: LLM-to-LM Interpreter for Enhanced Text-Attributed Graph Representation Learning
Representation learning on text-attributed graphs (TAGs) has become a
critical research problem in recent years. A typical example of a TAG is a
paper citation graph, where the text of each paper serves as node attributes.
Initial graph neural network (GNN) pipelines handled these text attributes by
transforming them into shallow or hand-crafted features, such as skip-gram or
bag-of-words features. Recent efforts have focused on enhancing these pipelines
with language models (LMs), which typically demand intricate designs and
substantial computational resources. With the advent of powerful large language
models (LLMs) such as GPT or Llama2, which demonstrate an ability to reason and
to utilize general knowledge, there is a growing need for techniques which
combine the textual modelling abilities of LLMs with the structural learning
capabilities of GNNs. Hence, in this work, we focus on leveraging LLMs to
capture textual information as features, which can be used to boost GNN
performance on downstream tasks. A key innovation is our use of explanations as
features: we prompt an LLM to perform zero-shot classification, request textual
explanations for its decision-making process, and design an LLM-to-LM
interpreter to translate these explanations into informative features that
enhance downstream GNNs. Our experiments demonstrate that our method achieves
state-of-the-art results on well-established TAG datasets, including Cora,
PubMed, ogbn-arxiv, as well as our newly introduced dataset, arXiv-2023.
Furthermore, our method significantly speeds up training, achieving a 2.88
times improvement over the closest baseline on ogbn-arxiv. Lastly, we believe
the versatility of the proposed method extends beyond TAGs and holds the
potential to enhance other tasks involving graph-text data~\footnote{Our codes
and datasets are available at: \url{https://github.com/XiaoxinHe/TAPE}}
Changing trends of disease burden of stroke from 1990 to 2019 and its predictions among the Chinese population
ObjectiveThis study aimed to understand the temporal trends in the disease burden of stroke and its attributable risk factors in China, along with the future trends in the next 25 years, that is important for effective prevention strategies and improvement, and to provide new insights into the age- and sex-specific incidence, prevalence, mortality, disability-adjusted life-years (DALYs) and their trends from 1990 to 2019, and the prediction in the next 25 years.MethodsThe Global Burden of Disease Study (2019) was used to extract the data on age- and sex-specific incidence, mortality, and disability-adjusted life-years (DALYs) of stroke in China, 1990–2019. We estimated the estimated annual percentage change (EAPC) to access the temporal trends of the disease burden of stroke. The R package called Nordpred was used to perform an age-period-cohort analysis to predict the prevalence of stroke.ResultsThe number of incidence cases, deaths, and DALYs of stroke increased from 1990 to 2019. Overall downward trends were observed in the age-standardized incidence rate (ASIR) from 1990 to 2019. Significant temporal trends in mortality and DALYs of stroke were observed. High systolic blood pressure, smoking, and high-sodium diet were the main driving forces for stroke. The DALYs lost attributable to smoking were different for male and female patients. In the next 25 years, the number of new cases and deaths from stroke should continue to increase. The ASIR and age-standardized mortality rate (ASMR) should show a downward trend among male and female patients.ConclusionDespite the overall rates of stroke declined over the period from 1990 to 2019, the absolute number of people affected by stroke has substantially increased. There has been a substantial increase in the burden of stroke due to risk factors and will continue to increase in the next 25 years
Expression of Robo4 in the fibrovascular membranes from patients with proliferative diabetic retinopathy and its role in RF/6A and RPE cells
Purpose: Robo4, a member of the roundabout (Robo) family, acts as a neuronal guidance receptor and plays some role in vasculogenesis and angiogenesis. This study investigated the effect of Robo4 on the formation of fibrovascular membranes (FVMs) from patients with proliferative diabetic retinopathy and its roles in choroid-retina endothelial (RF/6A) and human retinal pigment epithelial (RPE) cells. Methods: RT-PCR and immunohistochemistry were used to determine the levels of mRNA and the presence and distribution of Robo4 in FVMs. Small interfering RNA (siRNA) technology was used to knock down Robo4 expression and to study its effects on RF/6A and RPE cells in vitro. Cell proliferation, migration, spreading, cycling, and apoptosis were assessed with MTT assay, Boyden chamber assay, immunocytochemistry, and flow cytometry. Tube formation by RF/6A on Matrigel was also analyzed. Results: The level of Robo4 mRNA was high in FVMs. Robo4 was expressed in the vessels and fibrous-like tissue co-immunostained for CD31 and GFAP, respectively. Robo4 siRNA knockdown inhibited cell proliferation and migration. Tube formation by RF/6A cells was also disturbed. Under hypoxic conditions, more apoptotic cells were evident among the knockdown cells than among the control cells (p < 0.01). Conclusions: Robo4 may play a role in the formation of FVMs. Silencing the expression of Robo4 in RF/6A and RPE cells inhibited their proliferation and reduced their tolerance of hypoxic conditions, suggesting physiologic functions of Robo4 in the cells of the retina.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000267136400001&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Biochemistry & Molecular BiologyOphthalmologySCI(E)PubMed15ARTICLE112-131057-10691
Astrocytes from the contused spinal cord inhibit oligodendrocyte differentiation of adult oligodendrocyte precursor cells by increasing the expression of bone morphogenetic proteins.
Promotion of remyelination is an important therapeutic strategy to facilitate functional recovery after traumatic spinal cord injury (SCI). Transplantation of neural stem cells (NSCs) or oligodendrocyte precursor cells (OPCs) has been used to enhance remyelination after SCI. However, the microenvironment in the injured spinal cord is inhibitory for oligodendrocyte (OL) differentiation of NSCs or OPCs. Identifying the signaling pathways that inhibit OL differentiation in the injured spinal cord could lead to new therapeutic strategies to enhance remyelination and functional recovery after SCI. In the present study, we show that reactive astrocytes from the injured rat spinal cord or their conditioned media inhibit OL differentiation of adult OPCs with concurrent promotion of astrocyte differentiation. The expression of bone morphogenetic proteins (BMP) is dramatically increased in the reactive astrocytes and their conditioned media. Importantly, blocking BMP activity by BMP receptor antagonist, noggin, reverse the effects of active astrocytes on OPC differentiation by increasing the differentiation of OL from OPCs while decreasing the generation of astrocytes. These data indicate that the upregulated bone morphogenetic proteins in the reactive astrocytes are major factors to inhibit OL differentiation of OPCs and to promote its astrocyte differentiation. These data suggest that manipulation of BMP signaling in the endogenous or grafted NSCs or OPCs may be a useful therapeutic strategy to increase their OL differentiation and remyelination and enhance functional recovery after SCI
Transplantation of Ciliary Neurotrophic Factor-Expressing Adult Oligodendrocyte Precursor Cells Promotes Remyelination and Functional Recovery after SpinalCord Injury
Demyelination contributes to the dysfunction after traumatic spinal cord injury (SCI). We explored whether the combination of neurotrophic factors and transplantation of adult rat spinal cord oligodendrocyte precursor cells (OPCs) could enhance remyelination and functional recovery after SCI. Ciliary neurotrophic factor (CNTF) was the most effective neurotrophic factor to promote oligodendrocyte (OL) differentiation and survival of OPCs in vitro. OPCs were infected with retroviruses expressing enhanced green fluorescent protein (EGFP) or CNTF and transplanted into the contused adult thoracic spinal cord 9 d after injury. Seven weeks after transplantation, the grafted OPCs survived and integrated into the injured spinal cord. The survival of grafted CNTF-OPCs increased fourfold compared with EGFP-OPCs. The grafted OPCs differentiated into adenomatus polyposis coli (APC+) OLs, and CNTF significantly increased the percentage of APC+ OLs from grafted OPCs. Immunofluorescent and immunoelectron microscopic analyses showed that the grafted OPCs formed central myelin sheaths around the axons in the injured spinal cord. The number of OL-remyelinated axons in ventrolateral funiculus (VLF) or lateral funiculus (LF) at the injured epicenter was significantly increased in animals that received CNTF-OPC grafts compared with all other groups. Importantly, 75% of rats receiving CNTF-OPC grafts recovered transcranial magnetic motor-evoked potential and magnetic interenlargement reflex responses, indicating that conduction through the demyelinated axons in VLF or LF, respectively, was partially restored. More importantly, recovery of hindlimb locomotor function was significantly enhanced in animals receiving grafts of CNTF-OPCs. Thus, combined treatment with OPC grafts expressing CNTF can enhance remyelination and facilitate functional recovery after traumatic SCI
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Tuberculosis burden in China: a high prevalence of pulmonary tuberculosis in household contacts with and without symptoms
Background: In the context of decreasing tuberculosis prevalence in China, we examined the effectiveness of screening household contacts of tuberculosis patients. Methods: A tuberculosis survey was conducted in 2008. All 3,355 household contacts of notified tuberculosis cases were examined with a questionnaire interview, chest X-ray and three sputum smear tests. The effectiveness was examined by comparing the prevalence of pulmonary tuberculosis in household contacts with or without presenting clinical symptoms against the respective notification rates. Regression models were used to evaluate the factors associated with pulmonary tuberculosis. Results: Of the 3,355 household contacts, 92 members (2.7%) had pulmonary tuberculosis, among which 46 cases were asymptomatic. The prevalence of pulmonary tuberculosis and smear positive cases in household contacts without symptoms were 20 and 7 times higher than the notification rates in 2008, while those in household contacts with symptoms were 247 and 108 times higher than notification rates, respectively. The patients detected were mainly Index Cases’ spouses, sisters/brothers and those who were in contact with female Index Cases. Conclusions: The present study provides convincing evidence that household contacts of notified tuberculosis cases are at higher risk of developing tuberculosis. Routine screening for household contacts without any symptoms is recommended for sustained tuberculosis control in China as well as in the world
The change in blood glucose levels in tuberculosis patients before and during anti-tuberculosis treatment in China.
OBJECTIVE: We aimed to observe (i) changes in fasting blood glucose (FBG) in tuberculosis (TB) patients before and during anti-TB treatment, (ii) whether FBG levels were stable or unstable and (iii) baseline characteristics associated with an unstable FBG. METHOD: TB patients consecutively attended six clinics or hospitals. FBG measurements were made at months 0, 2 and 6. Data analysis was performed using the chi-square test and multivariate logistic regression. RESULTS: Of 232 patients without diabetes mellitus (DM) whose initial FBG < 6.1 mmol/L, over 90% maintained FBG < 6.1 mmol/L during treatment and no patient developed DM. Of 17 patients without DM and initial FBG between 6.1 and 6.9 mmol/L, over half had FBG < 6.1 mmol/L during treatment and no patient had DM at the end of treatment. Eight DM patients with already known DM had their FBG controlled at < 7.0 mmol/L during treatment. There were 13 DM patients newly diagnosed with FBG ≥ 7.0 mmol/L, and 69% continued to have FBG ≥ 7.0 mmol/L. After adjustment for confounding, the odds for an unstable FBG were higher for HIV-positive status, already having DM, smoking and coming to hospitals rather than clinics. CONCLUSION: TB patients who do not have DM based on FBG measurements do not develop DM during anti-TB treatment. Those newly diagnosed with DM on screening in general maintain their DM status with high FBG and need to be better managed
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