Zero-shot stance detection based on cross-domain feature enhancement by contrastive learning

Zero-shot stance detection is challenging because it requires detecting the stance of previously unseen targets in the inference phase. The ability to learn transferable target-invariant features is critical for zero-shot stance detection. In this work, we propose a stance detection approach that can efficiently adapt to unseen targets, the core of which is to capture target-invariant syntactic expression patterns as transferable knowledge. Specifically, we first augment the data by masking the topic words of sentences, and then feed the augmented data to an unsupervised contrastive learning module to capture transferable features. Then, to fit a specific target, we encode the raw texts as target-specific features. Finally, we adopt an attention mechanism, which combines syntactic expression patterns with target-specific features to obtain enhanced features for predicting previously unseen targets. Experiments demonstrate that our model outperforms competitive baselines on four benchmark datasets

Fusion of EML4 and ALK is associated with development of lung adenocarcinomas lacking EGFR and KRAS mutations and is correlated with ALK expression

<p>Abstract</p> <p>Background</p> <p>The anaplastic lymphoma kinase (<it>ALK</it>) gene is frequently involved in translocations that lead to gene fusions in a variety of human malignancies, including lymphoma and lung cancer. Fusion partners of <it>ALK </it>include <it>NPM</it>, <it>EML4</it>, <it>TPM3</it>, <it>ATIC</it>, <it>TFG</it>, <it>CARS</it>, and <it>CLTC</it>. Characterization of ALK fusion patterns and their resulting clinicopathological profiles could be of great benefit in better understanding the biology of lung cancer.</p> <p>Results</p> <p>RACE-coupled PCR sequencing was used to assess <it>ALK </it>fusions in a cohort of 103 non-small cell lung carcinoma (NSCLC) patients. Within this cohort, the <it>EML4</it>-<it>ALK </it>fusion gene was identified in 12 tumors (11.6%). Further analysis revealed that <it>EML4</it>-<it>ALK </it>was present at a frequency of 16.13% (10/62) in patients with adenocarcinomas, 19.23% (10/52) in never-smokers, and 42.80% (9/21) in patients with adenocarcinomas lacking <it>EGFR </it>and <it>KRAS </it>mutations. The <it>EML4</it>-<it>ALK </it>fusion was associated with non-smokers (<it>P </it>= 0.03), younger age of onset (<it>P </it>= 0.03), and adenocarcinomas without <it>EGFR</it>/<it>KRAS </it>mutations (<it>P </it>= 0.04). A trend towards improved survival was observed for patients with the <it>EML4</it>-<it>ALK </it>fusion, although it was not statistically significant (<it>P </it>= 0.20). Concurrent deletion in <it>EGFR </it>exon 19 and fusion of <it>EML4</it>-<it>ALK </it>was identified for the first time in a Chinese female patient with an adenocarcinoma. Analysis of ALK expression revealed that ALK mRNA levels were higher in tumors positive for the <it>EML</it>-<it>ALK </it>fusion than in negative tumors (normalized intensity of 21.99 vs. 0.45, respectively; <it>P </it>= 0.0018). However, expression of EML4 did not differ between the groups.</p> <p>Conclusions</p> <p>The <it>EML4</it>-<it>ALK </it>fusion gene was present at a high frequency in Chinese NSCLC patients, particularly in those with adenocarcinomas lacking <it>EGFR</it>/<it>KRAS </it>mutations. The <it>EML4</it>-<it>ALK </it>fusion appears to be tightly associated with ALK mRNA expression levels. RACE-coupled PCR sequencing is a highly sensitive method that could be used clinically for the identification of <it>EML4</it>-<it>ALK</it>-positive patients.</p

Evidence based on Mendelian randomization and colocalization analysis strengthens causal relationships between structural changes in specific brain regions and risk of amyotrophic lateral sclerosis

BackgroundAmyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by the degeneration of motor neurons in the brain and spinal cord with a poor prognosis. Previous studies have observed cognitive decline and changes in brain morphometry in ALS patients. However, it remains unclear whether the brain structural alterations contribute to the risk of ALS. In this study, we conducted a bidirectional two-sample Mendelian randomization (MR) and colocalization analysis to investigate this causal relationship.MethodsSummary data of genome-wide association study were obtained for ALS and the brain structures, including surface area (SA), thickness and volume of subcortical structures. Inverse-variance weighted (IVW) method was used as the main estimate approach. Sensitivity analysis was conducted detect heterogeneity and pleiotropy. Colocalization analysis was performed to calculate the posterior probability of causal variation and identify the common genes.ResultsIn the forward MR analysis, we found positive associations between the SA in four cortical regions (lingual, parahippocampal, pericalcarine, and middle temporal) and the risk of ALS. Additionally, decreased thickness in nine cortical regions (caudal anterior cingulate, frontal pole, fusiform, inferior temporal, lateral occipital, lateral orbitofrontal, pars orbitalis, pars triangularis, and pericalcarine) was significantly associated with a higher risk of ALS. In the reverse MR analysis, genetically predicted ALS was associated with reduced thickness in the bankssts and increased thickness in the caudal middle frontal, inferior parietal, medial orbitofrontal, and superior temporal regions. Colocalization analysis revealed the presence of shared causal variants between the two traits.ConclusionOur results suggest that altered brain morphometry in individuals with high ALS risk may be genetically mediated. The causal associations of widespread multifocal extra-motor atrophy in frontal and temporal lobes with ALS risk support the notion of a continuum between ALS and frontotemporal dementia. These findings enhance our understanding of the cortical structural patterns in ALS and shed light on potentially viable therapeutic targets

Iurnal Variability of Airway Hyperresponsiveness in Asthma Patients

BackgroundThere are daytime variability in pulmonary function indexes such as peak expiratory flow (PEF) and forced expiratory volume in 1 second (FEV1) in asthma patients. Studies evaluating the effects of drug therapy on lung function and airway hyperresponsiveness (AHR) in asthma patients all required patients to perform spirometry and bronchial challenge test in the same time point of the days. However, whether there is a daily diurnal AHR variability is still not clear.ObjectiveTo explore the characteristics and diurnal variability of AHR in asthma patients.MethodsThe data of 202 patients with asthma who consulted in respiratory department of the First Affiliated Hospital of Guangzhou Medical University from January 2018 to September 2020 were included for statistical analysis. All patients completed the methacholine bronchial provocation tests, they were divided into the morning detection group (morning group) with 81 cases and the afternoon detection group (afternoon group) with 121 cases; according to the disease course, 98 cases were divided into the initial diagnosis group if the disease course was ≤6 months, and 104 cases were divided into the follow-up group if the disease course was &gt;6 months. The initial diagnosis group and the follow-up group were divided into the initial diagnosis morning group, the initial diagnosis afternoon group, the follow-up morning group, and the follow-up afternoon group according to the detection time; according to the AHR, the patients were divided into very mild, mild, moderate and severe groups. The characteristics of AHR and the main pulmonary function indexes including FVC%pred, FEV1%pred, PEF%pred, MMEF%pred, MEF50%pred, MEF25%pred, PD20-FEV1, PD20-PEF, PD20-MMEF, PD20-MEF25%, PD20-MEF50% of these groups were analyzed and compared.ResultsThere were no significant differences of the math pulmonary function indexes and PD20 between morning and afternoon groups (P&lt;0.05) . FEV1%pred and PD20-PEF were significantly higher in initial diagnosed group than follow-up group (P&lt;0.05) . There was no significant difference in FVC%pred, PEF%pred, MMEF%pred, MEF50%pred, MEF25%pred, PD20-FEV1, PD20-MMEF, PD20-MEF25%, and PD20-MEF50% between the initial visit group and the follow-up visit group (P&gt;0.05) . In follow-up group, MMEF%pred and MEF50%pred were higher in afternoon than in morning (P&lt;0.05) . There were no differences of lung function and AHR between morning and afternoon in initial diagnosed group (P&lt;0.05) . No obvious correlations were found between disease history and PD20. There were no significant differences of PD20-FEV1 between the morning and afternoon, initial diagnosed and follow-up (P&gt;0.05) .ConclusionThe longer the duration of asthma, more serious impairment of lung function found in asthma, while the AHR had no significant difference between morning and afternoon

PARP-1 genetic polymorphism associated with radiation sensitivity of non-small cell lung cancer

About 70% of non-small cell lung cancer (NSCLC) patients require radiotherapy. However, due to the difference in radiation sensitivity, the treatment outcome may differ for the same pathology and choice of treatment. Poly (ADP-ribose) polymerase 1 (PARP-1) is a key gene responsible for DNA repair and is involved in base excision repair as well as repair of single strand break induced by ionizing radiation and oxidative damage. In order to investigate the relationship between PARP-1 gene polymorphism and radiation sensitivity in NSCLC, we collected 141 primary NSCLC patients undergoing three-dimensional conformal radiotherapy. For each case, the gross tumor volumes (GTV) before radiation and that after 40 Gy radiation were measured to calculate the tumor regression rate. TaqMan real-time polymerase chain reaction was performed to genotype the single-nucleotide polymorphisms (SNPs). Genotype frequencies for PARP-1 genotypes were 14.2% for C/C, 44.7% for C/G and 41.1% for G/G. The average tumor regression rate after 40 Gy radiation therapy was 35.1% ± 0.192. Tumor regression rate of mid-term RT of C/C genotype was 44.6% ± 0.170, which was higher than that of genotype C/G and G/G (32.4% ± 0.196 and 34.8% ± 0.188, respectively) with statistical significance (F = 3.169 p = 0.045). The higher tumor regression rate in patients with C/C genotype suggested that G allele was a protective factor against radiation therapy. Using the median tumor regression rate of 34%, we divided the entire cohort into two groups, and found that the frequency distribution of PARP-1 gene rs3219073 had significant difference between these two groups (p &lt; 0.05). These results showed that PARP-1 gene polymorphism may affect patient radiation sensitivity and predict the efficacy of radiotherapy. It therefore presents an opportunity for developing new therapeutic targets to improve radiotherapy outcome

Building osteogenic microenvironments with a double-network composite hydrogel for bone repair

The critical factor determining the in vivo effect of bone repair materials is the microenvironment, which greatly depends on their abilities to promote vascularization and bone formation. However, implant materials are far from ideal candidates for guiding bone regeneration due to their deficient angiogenic and osteogenic microenvironments. Herein, a double-network composite hydrogel combining vascular endothelial growth factor (VEGF)-mimetic peptide with hydroxyapatite (HA) precursor was developed to build an osteogenic microenvironment for bone repair. The hydrogel was prepared by mixing acrylated β-cyclodextrins and octacalcium phosphate (OCP), an HA precursor, with gelatin solution, followed by ultraviolet photo-crosslinking. To improve the angiogenic potential of the hydrogel, QK, a VEGF-mimicking peptide, was loaded in acrylated β-cyclodextrins. The QK-loaded hydrogel promoted tube formation of human umbilical vein endothelial cells and upregulated the expression of angiogenesis-related genes, such as Flt1 , Kdr , and VEGF , in bone marrow mesenchymal stem cells. Moreover, QK could recruit bone marrow mesenchymal stem cells. Furthermore, OCP in the composite hydrogel could be transformed into HA and release calcium ions facilitating bone regeneration. The double-network composite hydrogel integrated QK and OCP showed obvious osteoinductive activity. The results of animal experiments showed that the composite hydrogel enhanced bone regeneration in skull defects of rats, due to perfect synergistic effects of QK and OCP on vascularized bone regeneration. In summary, improving the angiogenic and osteogenic microenvironments by our double-network composite hydrogel shows promising prospects for bone repair