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1.
Comput Biol Med ; 171: 108103, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38335822

ABSTRACT

Ultrasound imaging, as a portable and radiation-free modality, presents challenges for accurate segmentation due to the variability of lesions and the similar intensity values of surrounding tissues. Current deep learning approaches leverage convolution for extracting local features and self-attention for handling global dependencies. However, traditional CNNs are spatially local, and Vision Transformers lack image specific bias and are computationally demanding. In response, we propose the Global-Local Fusion Network (GLFNet), a hybrid structure addressing the limitations of both CNNs and Vision Transformers. The GLFNet, featuring Global-Local Fusion Blocks (GLFBlocks), integrates global semantic information with local details to improve segmentation. Each GLFBlock comprises Global and Local Branches for feature extraction in parallel. Within the Global and Local Branches, we introduce the Self-Attention Convolution Fusion Block (SACFBlock), which includes a Spatial-Attention Module and Channel-Attention Module. Experimental results show that our proposed GLFNet surpasses its counterparts in the segmentation tasks, achieving the overall best results with an mIoU of 79.58% and Dice coefficient of 74.62% in the DDTI dataset, an mIoU of 76.61% and Dice coefficient of 71.04% in the BUSI dataset, and an mIoU of 86.77% and Dice coefficient of 87.38% in the BUID dataset. The fusion of local and global features contributes to enhanced performance, making GLFNet a promising approach for ultrasound image segmentation.


Subject(s)
Image Processing, Computer-Assisted , Semantics , Ultrasonography
2.
Ecotoxicol Environ Saf ; 222: 112549, 2021 Oct 01.
Article in English | MEDLINE | ID: mdl-34325200

ABSTRACT

2,2',4,4'-tetrabromodiphenyl ether (BDE-47)-induced nephrotoxicity is closely associated with oxidative stresses and mitochondrial abnormalities. Mitochondrial fusion and fission dynamics are crucial for maintaining mitochondrial and cellular physiological homeostasis. However, the detailed mechanisms through which BDE-47 disrupts this dynamic and contributes to renal injuries are still not fully understood. The porcine kidney-15 (PK15) cell line, a well-defined in vitro animal renal toxicological model, was exposed to BDE-47 with concentrations of 12.5, 25, 50, and 100 µM, respectively. Cell viability, the levels of reactive oxygen species (ROS) and adenosine triphosphate (ATP), the mitochondrial membrane potential (MMP), and the expression levels of key mitochondrial fusion and fission proteins were assessed. BDE-47 reduced cell viability and disrupted mitochondrial dynamics by inhibiting mitochondrial fusion and fission simultaneously, leading to MMP decreases, ROS overgeneration, ATP depletion, and cellular disintegration in a dose-dependent manner. Additionally, the mitochondrial division inhibitor (Mdivi-1) with the concentration of 20 µM observed to restore the downregulation of mitochondrial fusion and fission proteins, alleviate damages in mitochondrial morphology and functionality, correct ROS overproduction, and enable cell survival. The antioxidant N-acety-L-cysteine (NAC) with the concentration of 1 mM also simultaneously reversed the imbalance of mitochondrial dynamics, decreased ROS production, and restored mitochondrial morphology in PK15 cells exposed to BDE-47. Our data provide new insights indicating that BDE-47 disrupts mitochondrial fusion/fission dynamics to induce mitochondrial abnormalities, triggering oxidative stresses and thus contributing to PK15 cell dysfunction. ROS-dependent pathways in mitochondrial dynamics may provide a new avenue for developing effective strategies to protect cells against BDE-47-induced nephrotoxicity.


Subject(s)
Halogenated Diphenyl Ethers , Mitochondrial Dynamics , Animals , Halogenated Diphenyl Ethers/toxicity , Kidney , Oxidative Stress , Reactive Oxygen Species , Swine
3.
Ecotoxicol Environ Saf ; 208: 111638, 2021 Jan 15.
Article in English | MEDLINE | ID: mdl-33396158

ABSTRACT

The flame retardant decabrominated diphenyl ether (BDE-209) is a widely used chemical in a variety of products and exists extensively in the environment. BDE-209 has been reported to induce kidney injury and dysfunction. However, the causes and mechanisms of its nephrotoxicity are still under investigation. In this study, 150 male broilers were exposed to BDE-209 concentrations of 0, 0.004, 0.04, 0.4, 4.0 g/kg for 42 days. The relative kidney weight, histopathology, markers of renal injury, oxidative stress, inflammation, apoptosis and the expression of MAPK signaling pathways-related proteins were assessed. The results showed that the concentrations of blood urea nitrogen (BUN), creatinine (CRE) and the neutrophil gelatinase-associated lipocalin (NGAL), significantly increased after exposure to BDE-209 with the doses more than 0.04 g/kg. Similarly, severe damage of renal morphology was observed, including atrophy and necrosis of glomeruli, and swelling and granular degeneration of the renal tubular epithelium. In the renal homogenates, the oxidative stress was evidenced by the elevated concentrations of MDA and NO, and decreased levels of GSH-Px, GSH and SOD. Due to the inflammatory response, the level of NF-κB and the pro-inflammatory cytokines TNF-α, IL-1ß, IL-18 were remarkably upregulated, while the content of the anti-inflammatory cytokine IL-10 decreased. Additionally, the apoptotic analysis showed notable upregulations of Bax/Bcl-2 ratio, the relative expression of p-ERK1/2 and p-JNK1/2, and the expression of Bax, cytochrome c and caspase 3. The present study indicates that BDE-209 exposure can cause nephrotoxicity in broilers through oxidative stress and inflammation, which activate the phosphorylation of key proteins of the MAPK signaling pathways, and subsequently induce mitochondria-mediated kidney apoptosis.


Subject(s)
Acute Kidney Injury/chemically induced , Environmental Pollutants/toxicity , Flame Retardants/toxicity , Halogenated Diphenyl Ethers/toxicity , Acute Kidney Injury/metabolism , Acute Kidney Injury/pathology , Animals , Apoptosis/drug effects , Chickens , Inflammation/chemically induced , MAP Kinase Signaling System/drug effects , Male , Oxidative Stress/drug effects
4.
Food Chem Toxicol ; 139: 111277, 2020 May.
Article in English | MEDLINE | ID: mdl-32217092

ABSTRACT

T-2 toxin, one of the most toxic mycotoxins, is commonly presented along with its metabolites, HT-2 toxin, neosolaniol (NEO), T-2 triol, and T-2 tetraol in foodstuff and feed. The aim of this study was to evaluate the cytotoxic effects of T-2 toxin alone and in combination with its metabolites on porcine Leydig cells. Based on the determination of cell viability with CCK-8, toxicological interactions were investigated using Combination Index method. The cytotoxic potency of five tested mycotoxins individual and their mixtures all showed with a dose-dependent manner. In view of IC50 values, the decreasing cytotoxicity of mycotoxins was ranking: T-2 toxin > HT-2 toxin > T-2 triol > NEO > T-2 tetraol. Combinations of T-2+HT-2, T-2+NEO, and HT-2+NEO displayed synergism at low doses but antagonism at high doses, while the ternary combination of T-2+HT-2+NEO revealed adverse situation from antagonism to synergism. All binary and ternary combinations of T-2 toxin, T-2 triol, and T-2 tetraol exhibited antagonistic interactions. Our results suggest that the co-occurrence of T-2 toxin and its metabolites might pose a slight threat to reproductive health due to antagonistic interactions. However, the synergy observed should be not ignored especially at low doses of mycotoxins co-occurrence in the diet.


Subject(s)
Leydig Cells/drug effects , Leydig Cells/metabolism , T-2 Toxin/analogs & derivatives , T-2 Toxin/toxicity , Animals , Cell Survival/drug effects , Drug Combinations , Drug Interactions , Male , Mycotoxins/toxicity , Swine , T-2 Toxin/chemistry , Trichothecenes/chemistry , Trichothecenes/toxicity
5.
Eur J Cancer Prev ; 29(6): 531-537, 2020 11.
Article in English | MEDLINE | ID: mdl-31922974

ABSTRACT

Major histocompatibility complex (MHC) class II regulatory genes play a paramount role in immune response that can exert a predominant influence on clinical outcome of Epstein-Barr virus infection consistently assumed as the main pathogenetic factor for nasopharyngeal carcinoma. To elucidate the relationship between allelic variants of MHC class II regulatory genes and susceptibility to nasopharyngeal carcinoma, a total of 28 polymorphic loci at MHC class II regulatory genes, involving CIITA, CREB1, RFX family genes (RFX5, RFXAP, and RFXANK), and NFY family genes (NFYA, NFYB, and NFYC), were genotyped by multiplex SNaPshot minisequencing in 137 patients with nasopharyngeal carcinoma and 107 healthy controls from the southern Chinese population. Allelic analysis disclosed that rs7404873, rs6498121, rs6498126, and rs56074043 shared correlations with nasopharyngeal carcinoma (Ptrend < 0.05). Further, rs6498126 on CIITA was independently associated with the risk of developing nasopharyngeal carcinoma (CC vs. GG, odds ratio: 7.386, 95% confidence interval: 1.934-28.207, Ptrend < 0.01). Conversely, rs7404873 on CIITA and rs56074043 on NFYB manifested epistatic interaction to decreased susceptibility of nasopharyngeal carcinoma (rs7404873, TT vs. GG, odds ratio: 0.256, 95% confidence interval: 0.088-0.740, Ptrend < 0.05; rs56074043, AA vs. AG, odds ratio: 0.341, 95% confidence interval: 0.129-0.900, Ptrend < 0.05). Additionally, bioinformatics analysis revealed that the three variants were transcriptional regulatory in function and might impact the expression of nearby genes. The findings suggested genetic variants on MHC class II regulatory genes contributed to nasopharyngeal carcinoma susceptibility and might provide new insights for screening high-risk population.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Neoplasms/drug therapy , Adult , Aged , Aged, 80 and over , Biomarkers, Tumor , Case-Control Studies , Combined Modality Therapy , Female , Follow-Up Studies , Gene Expression Regulation, Neoplastic , Humans , Lymphatic Metastasis , Male , Middle Aged , Neoplasm Invasiveness , Neoplasm Recurrence, Local/drug therapy , Neoplasm Recurrence, Local/pathology , Neoplasms/pathology , Prognosis , Retrospective Studies , Survival Rate , Tumor Cells, Cultured
6.
Cell Death Dis ; 10(8): 613, 2019 08 14.
Article in English | MEDLINE | ID: mdl-31409797

ABSTRACT

Tumor-necrosis factor (TNF) and its superfamily members are pleiotropic cytokines. Activation of TNF can lead to distinct cellular outcomes including inflammation, cell survival, and different forms of cell death, such as apoptosis and necrosis in a context-dependent manner. However, our understanding of what determines the versatile functions of TNF is far from complete. Here, we examined the molecular mechanisms that distinguish the forms of cell death induced by Eiger (Egr), the sole homolog of TNF in Drosophila. We show that expression of Egr in the developing Drosophila eye simultaneously induces apoptosis and apoptosis-independent developmental defects indicated by cellular disorganization, both of which rely on the c-Jun N-terminal kinase (JNK) signaling activity. Intriguingly, when effector caspases DrICE and Dcp-1 are defective or inhibited, expression of Egr triggers necrosis which is characterized by loss of cell membrane integrity, translucent cytoplasm, and aggregation of cellular organelles. Moreover, such Egr-induced necrosis depends on the catalytic activity of the initiator caspase Dronc and the input from JNK signaling but is independent of their roles in apoptosis. Further mosaic analysis with mutants of scribble (scrib), an evolutionarily conserved tumor suppressor gene regulating cell polarity, suggests that Egr/JNK-mediated apoptosis and necrosis establish a two-layered defense system to inhibit the oncogenic growth of scrib mutant cells. Together, we have identified caspase- and JNK-dependent mechanisms underlying Egr-induced apoptosis versus necrosis and their fail-safe roles in tumor suppression in an intact organism in vivo.


Subject(s)
Caspases/genetics , Drosophila Proteins/genetics , Genes, Tumor Suppressor , Membrane Proteins/genetics , Animals , Apoptosis/genetics , Cell Polarity/genetics , Disease Models, Animal , Drosophila melanogaster/genetics , Gene Expression Regulation/genetics , Humans , JNK Mitogen-Activated Protein Kinases/genetics , MAP Kinase Signaling System/genetics , Necrosis/genetics , Necrosis/pathology , Neoplasms/genetics , Neoplasms/pathology , Tumor Necrosis Factor-alpha/genetics
7.
Front Aging Neurosci ; 11: 24, 2019.
Article in English | MEDLINE | ID: mdl-30863299

ABSTRACT

Low DJ-1 protein level caused by DJ-1 gene mutation leads to autosomal recessive Parkinson's disease (PD) due to impaired antioxidative activity. In sporadic PD patients, although mutations were rarely found, lower DJ-1 protein level was also reported. Dysregulation of DJ-1 gene expression might contribute to low DJ-1 protein level. Since the promoter is the most important element to initiate gene expression, whether polymorphisms in the DJ-1 promoter result in the dysregulation of gene expression, thus leading to low protein level and causing PD, is worth exploring. The DJ-1 promoter region was sequenced in a Chinese cohort to evaluate possible links between DJ-1 promoter polymorphisms, PD risk and clinical phenotypes. Dual-luciferase reporter assay was conducted to evaluate the influence of promoter polymorphisms on DJ-1 transcriptional activity. Related information in an existing genome-wide association studies (GWAS) database were looked up, meta-analysis of the present study and other previous reports was conducted, and expression quantitative trait loci (eQTL) analysis was performed to further explore the association. Three single nucleotide polymorphisms (SNPs) (rs17523802, rs226249, and rs35675666) and one 18 bp deletion (rs200968609) were observed in our cohort. However, there was no significant association between the four detected genetic variations and the risk of PD either in allelic or genotype model, in single-point analysis or haplotype analysis. This was supported by the meta-analysis of this study and previous reports as well as that of GWAS database PDGene. Dual luciferase reporter assay suggested these promoter polymorphisms had no influence on DJ-1 transcriptive activity, which is consistent with the eQTL analysis results using the data from GTEx database. Thus, DJ-1 promoter polymorphisms may play little role in the dysregulation of DJ-1 expression and PD susceptibility in sporadic PD.

8.
PLoS One ; 8(3): e59929, 2013.
Article in English | MEDLINE | ID: mdl-23555836

ABSTRACT

Previous studies have confirmed that patients with mandibular deviation often have abnormal morphology of their cervical vertebrae. However, the relationship between mandibular deviation, scoliosis, and trunk balance has not been studied. Currently, mandibular deviation is usually treated as a single pathology, which leads to poor clinical efficiency. We investigated the relationship of spine coronal morphology and trunk balance in adult patients with mandibular deviation, and compared the finding to those in healthy volunteers. 35 adult patients with skeletal mandibular deviation and 10 healthy volunteers underwent anterior X-ray films of the head and posteroanterior X-ray films of the spine. Landmarks and lines were drawn and measured on these films. The axis distance method was used to measure the degree of scoliosis and the balance angle method was used to measure trunk balance. The relationship of mandibular deviation, spine coronal morphology and trunk balance was evaluated with the Pearson correlation method. The spine coronal morphology of patients with mandibular deviation demonstrated an "S" type curve, while a straight line parallel with the gravity line was found in the control group (significant difference, p<0.01). The trunk balance of patients with mandibular deviation was disturbed (imbalance angle >1°), while the control group had a normal trunk balance (imbalance angle <1°). There was a significant difference between the two groups (p<0.01). The degree of scoliosis and shoulder imbalance correlated with the degree of mandibular deviation, and presented a linear trend. The direction of mandibular deviation was the same as that of the lateral bending of thoracolumbar vertebrae, which was opposite to the direction of lateral bending of cervical vertebrae. Our study shows the degree of mandibular deviation has a high correlation with the degree of scoliosis and trunk imbalance, all the three deformities should be clinically evaluated in the management of mandibular deviation.


Subject(s)
Mandible/abnormalities , Posture , Scoliosis/physiopathology , Adolescent , Adult , Case-Control Studies , Female , Humans , Male , Mandible/diagnostic imaging , Radiography , Scoliosis/diagnostic imaging , Spine/abnormalities , Spine/anatomy & histology , Spine/diagnostic imaging , X-Rays , Young Adult
9.
Sheng Wu Gong Cheng Xue Bao ; 19(1): 74-80, 2003 Jan.
Article in Chinese | MEDLINE | ID: mdl-15969040

ABSTRACT

Cis-1,2-dihydroxycyclohexa-3,5-diene (DHCD) can be used as a valuable chiral intermediates for applications in pharmaceuticals, aerospace, electrical and fine chemical industries. By on-line detection of toluene dioxygenase (TDO) activity in whole recombinant Escherichia coli JM109 (pKST11) cells that harbored TDO gene under a tac promoter, effects of IPTG and various benzene addition strategies on bioransformation of benzene to DHCD were investigated. When IPTG was used at the beginning of fermentation, the growth of cells was inhibited and TDO activity only maintained for 4 hours while same experiments with addition of IPTG at 6h or 8h generated TDO activity for 18 hours. Suitable induction time for IPTG was in the cell logarithmic growth phase and 0.5 mmol/L IPTG was sufficient for inducing maximum TDO activities. Benzene strongly inhibited the activity of TDO which catalyses the conversion of benzene to DHCD. It was found that both cell growth and TDO activity was remarkably inhibited by feeding of benzene vapor, only 7.5 g/L DHCD was obtained. While the benzene inhibition effect was ameliorated by two-liquid phase culture fermentation in which liquid paraffin was used as second phase in the broth. Using different initial ratios of paraffin to benzene in fed-batch culture, DHCD contents were increased to 22.6 g/L, which was 3-fold more compared with that in benzene vapor culture. A further improvement of DHCD production was achieved when the mixture of liquid paraffin and benzene was added continuously by peristaltic pump, the DHCD contents were increased to a final concentration of 36.8 g/L. It was proven that the key to improving DHCD production by recombinants is to prolong TDO activity in cells, which can be achieved by using suitable addition benzene strategies.


Subject(s)
Benzene/metabolism , Cyclohexanols/metabolism , Escherichia coli/metabolism , Escherichia coli/genetics , Fermentation/physiology , Oxygenases/genetics , Oxygenases/metabolism
10.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 38(5): 387-9, 2003 Sep.
Article in Chinese | MEDLINE | ID: mdl-14746329

ABSTRACT

OBJECTIVE: The aim of the study is to improve the anticorrosive property of the dental FeCrMo soft magnetic alloy covered with TiN film obtained by ion beam assisted deposition (IBAD) technology in oral environment. METHODS: The magnetic force of the FECrMo soft magnetic alloy after TiN film treated were measured by Instron test machine. An advanced electro-chemical method was used to measure the electric potential of corrosion (Ecorr), passive potential (Ep), passive current density (Ip), current density of corrosion (Icorr), polarization resistance (Rp), of FeCrMo soft magnetic alloy in simulated oral environment before and after surface modification. RESULTS: There were no statistic changes of the magnetic force in 4 groups after alloy with TiN film treated. Comparing with the alloy without surface modified, the Ecorr, Rp of FeCrMo soft magnetic alloy was obviously higher, and the Icorr, Ip and Ep were obviously lower. CONCLUSIONS: The anticorrosive property of the dental FeCrMo soft magnetic alloy with TiN film is better than that without modified.


Subject(s)
Dental Alloys , Dental Prosthesis Retention , Titanium/pharmacology , Chromium Alloys , Corrosion , Humans , Magnetics , Molybdenum
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