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Alzheimer's Disease (AD) is a common type of dementia, affecting human memory, language ability and behavior. Hippocampus is an important biomarker for AD diagnosis. Previous hippocampus-based biomarker analyses mainly focused on volume, texture and shape of the bilateral hippocampus. 3D convolutional neural networks (CNNs) can understand and extract complex morphology features from Magnetic resonance imaging (MRI) and have recently been developed for hippocampus-based AD classification. However, existing CNN models often have highly complex structures and require large amounts of training data. Here we propose an accurate and lightweight Densely Connected 3D convolutional neural network (DenseCNN) for AD classification based on hippocampus segments. DenseCNN was trained on 746 and tested on 187 pairs of hippocampus from Alzheimer's Disease Neuroimaging Initiative (ADNI) databases. DenseCNN has an average accuracy of 0.898, sensitivity of 0.985, specificity of 0.852, and area under curve (A UC) of0.979, which are better than or comparable to state-of-art approaches., (©2020 AMIA - All rights reserved.)

The ADAMs family belongs to the transmembrane protein superfamily of zinc-dependent metalloproteases, which consists of multiple domains. These domains have independent but complementary functions that enable them to participate in multiple biological processes. Among them, ADAM9 can not only participate in the degradation of extracellular matrix as a metalloprotease, but also mediate tumor cell adhesion through its deintegrin domain, which is closely related to tumor invasion and metastasis. It is widely expressed in a variety of tumor cells and can affect the proliferation, invasion and metastasis of related cancer cells. We provide our views on current progress, its increasing importance as a strategic treatment goal, and our vision for the future of ADAM9.

Objectives: Preeclampsia (PE), a pregnancy-specific disorder characterized by hypertension and a variety of organ failures, currently lacks effective treatments. Urate (hydroxyiso-) hydrolase, pseudogene ( URAHP ), which is also a long noncoding RNA (lncRNA), has higher expression in PE placentae than in normal controls and therefore acquires an investigation for the specific mechanism of regulation., Methods: Placentae were divided into two groups: those from patients with normal pregnancy (NP) (n = 3) and those from patients with PE (n = 3). Total RNA was extracted from the placentae and differentially expressed lncRNAs and mRNAs in PE and NP were identified by Arraystar Human LncRNA Expression Microarray V4.0 analysis. The microarray data were validated by profiling the noncoding RNA expression of URAHP in NP and PE placental tissues through quantitative real-time PCR (qRT-PCR). Then, we uncover the effect of URAHP on cell proliferation by CCK-8 assay and by 3D colony forming assay. Gene coexpression analysis was conducted to identify mRNAs coexpressed with URAHP. qRT-PCR and western blotting assays were used to measure the expression levels of URAHP and KISS1R in JAR and JET-3 cell lines., Results: A total of 675 differentially expressed lncRNAs (DELRs) [184 upregulated DELRs and 491 downregulated DELRs] and a total of 205 differently expressed genes (DEGs) [56 upregulated mRNAs and 149 downregulated mRNAs] were finally identified between PE and NP samples through high-throughput sequencing analysis. The expression of lncRNA URAHP was increased significantly in the placentae of women with preeclampsia when compared to those with normal pregnancies. The functional assay suggested that the downregulation of URAHP alters the proliferative capacity of JAR/JET-3 cells and that the overexpression of URAHP promotes the proliferation of HTR-8/SVneo cells. We also determined that URAHP and KISS1R are coexpressed., Conclusion: We demonstrated for the first time that the pseudogene URAHP may be associated with PE. The results of this study provide a new target for the comprehensive treatment of preeclampsia., Competing Interests: None., (AJTR Copyright © 2020.)

Atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine; ATR) is widely used as an herbicide, and its accumulation in the environment is a health risk to humans; for instance, it has been shown to cause dopaminergic neurotoxicity. MicroRNAs (miRNAs) are endogenous small RNAs that regulate gene expression in diverse physiological contexts; however, the extent of their involvement in the development of Parkinson's disease (PD) is not known. In this study, we carried out miRNA profiling of peripheral blood and brain tissue in a rat model of PD in order to identify factors that mediate PD pathogenesis. The miRNAmiR-7 is known to cause the downregulation of α-synuclein (α-syn), which is linked to the neuropathology of PD. Here we found that miR-7 was upregulated in brain tissue but downregulated in peripheral blood of rats with ATR-induced PD. We also found that miR-7 regulates the expression of brain-derived neurotrophic factor (BDNF) through an auto regulatory mechanism. These findings indicate that miRNA-7 regulates the BDNF/α-syn axis in the early stages of PD and can serve as a biomarker or therapeutic target for disease treatment., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Discerning the modular nature of human diseases through computational approaches calls for diverse data. The finding sites of diseases, like other disease phenotypes, possess rich information in understanding disease genetics. Yet, analysis of the rich knowledge of disease finding sites has not been comprehensively investigated. In this study, we built a large-scale disease organ network (DON) based on 76,561 disease-organ associations (for 37,615 diseases and 3492 organs) extracted from the United Medical Language System (UMLS) Metathesaurus. We investigated how phenotypic organ similarity among diseases in DON reflects disease gene sharing. We constructed a disease genetic network (DGN) using curated disease-gene associations and demonstrated that disease pairs with higher organ similarities not only are more likely to share genes, but also tend to share more genes. Based on community detection algorithm, we showed that phenotypic disease clusters on DON significantly correlated with genetic disease clusters on DGN. We compared DON with a state-of-art disease phenotype network, disease manifestation network (DMN), that we have recently constructed, and demonstrated that DON contains complementary knowledge for disease genetics understanding., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Lead (Pb) is a widespread environmental heavy metal toxicant and chronic Pb exposure can have irreversible effects on memory and cognitive function, which is closely related to dendritic spines. Studies have shown that SNX6 and Homer1 can regulate the growth of dendritic spines. We aimed to investigate the effect of Pb exposure on the dendritic spines in hippocampus, the expression of SNX6 and Homer1 in rats and PC12 cells. The animals were randomly divided to three groups: control group, low lead group and high lead group. PC12 cells were divided into 3 groups: 0 μM, 1 μM and 100 μM Pb acetate. The results showed that the Pb levels in blood and hippocampus of all exposure groups were significantly higher than that of the control group. The morphology of dendritic spines in hippocampus after Pb treatment was changed and the density of dendritic spines was reduced. The expression of SNX6 and Homer1 was decreased in Pb exposed groups compared with the control group. Furthermore, up-regulation of SNX6 expression could reverse the down-regulation of Pb exposure on Homer1. These results indicate that Pb exposure can reduce the expression of SNX6 and lead to a decrease in Homer1 expression, which affects the changes in dendritic spines causing learning and memory impairment., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Objectives: A significant number of researches have evidenced that occupational lead (Pb) exposure increased risks of cardiovascular disease. However, evidences about the potential effects of Pb on the cardiac conduction system are sparse and inconclusive. Besides, ryanodine receptors (RyRs) induced dysfunction of cardiac excitation contraction coupling which is considered to be one of the mechanisms in cardiovascular diseases. Therefore, we examined the association between occupational Pb exposure and ECG conduction abnormalities, as well as RyRs in Pb-induced ECG abnormalities., Methods: We investigated 529 Pb smelter workers, and measured blood lead (BPb), zinc protoporphyrin (ZPP), ECG outcomes and RyR expression levels. Based on BPb levels, the workers were divided into three groups: the BPb not elevated group, the BPb elevated group and the Pb poisoning group. Descriptive and multivariable analyses were performed., Results: Compared with the BPb not elevated group, the Pb poisoning group had a higher incidence of high QRS voltage, and a lower level of RyR1 gene expression (p<0.05). Further unconditional multivariable logistic regression analyses showed that high QRS voltage was positively related to BPb (OR=1.045, 95% CI 1.014 to 1.078) and inversely associated with RyR1 expression (OR=0.042, 95% CI 0.002 to 0.980) after adjusting for potential confounders. In addition, multiple linear regression analyses showed that the QTc interval was positively associated with ZPP (β=0.299, 95% CI 0.130 to 0.468) after adjusting for potential confounders., Conclusions: Our study provided evidences that occupational exposure to Pb may be associated with worse ECG outcomes (high QRS voltage), which might be related to decreased levels of RyR1., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. No commercial re-use. See rights and permissions. Published by BMJ.)

A large number of studies have evidenced that developmental neurotoxicity induced by lead (Pb) is related to oxidative injury. Furthermore, recent studies have found that developmental Pb exposure can induce neurodegeneration in old age. Because of the common presence of Pb in the environment, humans are exposed to this metal throughout their lifetime. However, few studies have explored the changes in lifespan profiles of neurotoxicity, as well as oxidative stress following lifetime Pb exposure. In the present study, rats were exposed to lead acetate from their embryonic stage to old age. Dynamic changes in neurodegeneration, oxidative stress, and endoplasmic reticulum (ER) stress in the brains at postnatal week 3 (PNW3, weaning), 41 weeks (PNW41, adulthood) and 70 weeks (PNW70, old age) were investigated. Pb exposure resulted in neurodegeneration with decreased neuronal densities and brain volumes in PNW3 and PNW70 rats; however, no significant changes occurred in PNW41 rats based on thionine stain analysis and magnetic resonance imaging (MRI) scans. Expression of the ER stress protein glucose-regulated protein 78 (GRP78) increased in Pb-exposed rats, which was associated with high levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG) in rat brains after Pb exposure in PNW3 and PNW70 rats. Our findings suggested that lifetime Pb exposure induced neurodegenerative injuries that began to occur in infancy, were relieved in adulthood, but intensified in old age. The critical periods for prevention or intervention in neurodegenerative diseases induced by Pb exposure occurred in early life., (Copyright © 2018 Elsevier B.V. All rights reserved.)

We, along with others, have shown previously that P21-activated kinase 1 (Pak1) plays a pivotal role in gastric cancer progression and metastasis. However, whether Pak1 controls gastric cancer metastasis by regulating microRNAs (miRNAs) has never been explored. Here, we report a novel mechanism of Pak1 in tumor metastasis. A detailed examination revealed that Pak1 interacts with and phosphorylates the serine 62 residue of ATF2 and then blocks its translocation into the nucleus. We also confirmed that ATF2 binds to the promoter of miR-132 and tightly regulates its transcription, thus explaining the regulatory mechanism of miR-132 by Pak1. miR-132 also significantly reduced cell adhesion, migration, and invasion of gastric cancer cells in vitro and significantly prevented tumor metastasis in vivo. miR-132 specifically inhibited hematogenous metastasis, but not lymph node or implantation metastases. In order to further delineate the effects of the Pak1/ATF2/miR-132 cascade on gastric cancer progression, we identified several targets of miR-132 using a bioinformatics TargetScan algorithm. Notably, miR-132 reduced the expression of CD44 and fibronectin1 (FN1), and such inhibition enabled lymphocytes to home in on gastric cancer cells and induce tumor apoptosis. Taken together, our studies establish a novel cell-signaling pathway and open new possibilities for therapeutic intervention of gastric cancer., (Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.)

It has recently been reported that transmembrane protease, serine 3 (TMPRSS3) is overexpressed in cancer. However, TMPRSS3 expression and its biological roles in breast cancer (BC) have not been reported. This study aims to investigate the TMPRSS3 expression in BC and its relation with the outcome of the BC. This study involves a total of 149 BC tissues and adjacent non-cancerous tissues that were diagnosed between 2004 and 2007. Immunohistochemistry is used to compare the pattern of TMPRSS3 expression in BC and in adjacent non-cancerous tissues. Kaplan-Meier and Cox regression analyses were used to assess the prognostic significance of TMPRSS3 expression among BC patients. The results are as follow: TMPRSS3 expression is significantly in BC compared to adjacent non-cancerous tissues. High TMPRSS3 expression was related to TNM stage, lymph node metastasis, and Ki-67 expression. Furthermore, the overall survival (OS) and disease-free survival (DFS) in BC patients with high TMPRSS3 expression were lower than those in patients with low TMPRSS3 expression. Based on multivariate analysis, lymph node metastasis, TNM stage and TMPRSS3 expression are independent prognostic factors for OS in BC, while lymph node metastasis and TMPRSS3 expression are independent prognostic factors for DFS in BC. This study proves that TMPRSS3 expression is an independent prognostic factor for BC patients. Bioinformatic analysis of potential TMPRSS3 binding proteins revealed that TMPRSS3 could be a key regulator of cancer pathways. This study helps us better understand the function of TMPRSS3 in cancer.

The p21-activated kinases have been implicated in the control of cell cycle progression. However, the biological mechanism underlying the role of p21-activated kinase 4 (PAK4) in cell cycle control remains unknown. Here, by using quantitative RT-PCR and immunoblot analyses, we discovered that over-expression of PAK4 could suppress cyclin-dependent kinase inhibitor 1C (p57(Kip2) ) expression in the MCF-7 human breast cancer cell line, whereas lentiviral vector-mediated small interfering RNA (siRNA) knockdown of PAK4 markedly promoted p57(Kip2) expression in MCF-7 cells. Furthermore, PAK4-mediated down-regulation of p57(Kip2) was reversed by MG132, a specific proteasome inhibitor. The ubiquitination assay confirmed that the activity of PAK4 attenuated p57(Kip2) protein stability through the ubiquitin-proteasome pathway in MCF-7 cells. Moreover, a significant inverse correlation between PAK4 and p57(Kip2) protein levels was observed in breast cancer tissues by immunohistochemical analysis. Taken together, our data demonstrate a novel function for PAK4 in regulating the stability of p57(Kip2) , possibly through the ubiquitin-proteasome pathway, leading to increased proliferation of breast cancer cells. Thus, PAK4 may be used as a potential diagnostic and therapeutic target for human breast cancer., (© 2013 Wiley Periodicals, Inc.)

Objective: To explore the effect of long-term lead exposure on brain iron in aged rats., Methods: SPF female and male Sprague-Dawley rats were respectively randomly divided into three groups: control, low lead-exposed, high lead-exposed. Lead-exposed female rats drank 0.8g/L or 1.5g/L lead acetate solutions through pregnancy until weaning and then the pups received 0.3g/L or 0.9g/L lead acetate solution depending on their group. Control group rats drank deionized water throughout the experiment. At the postnatal 18 months, one pup for per group was given an ultra structural detection of hippocampus, and the other male pups were measured the lead and iron concentration of blood and brain by GE MR 3.0T MR scanner and ICP-AES., Results: In comparing with control group, the lead concentrations of blood and brain in lead-exposed groups were significantly higher, and the iron contents of brain and cortex, hippocampus, thalamus were significantly higher in 0.9g/L lead-exposed group. Also, it was highly positively correlated between blood lead and iron of blood, cortex, hippocampus, thalamus, respectively. With the dose of lead-exposed increased, cytoplasm, nucleus, mitochondrial structure and synaptic structure had suffered vary degrees of damage from ultra structural detection of hippocampus, it could be observed early neuronal apoptosis., Conclusion: Lead induced neurodegenerative diseases might be related to iron overload which caused by lead exposure.