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1.
Comput Biol Med ; 172: 108284, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38503086

RESUMO

3D MRI Brain Tumor Segmentation is of great significance in clinical diagnosis and treatment. Accurate segmentation results are critical for localization and spatial distribution of brain tumors using 3D MRI. However, most existing methods mainly focus on extracting global semantic features from the spatial and depth dimensions of a 3D volume, while ignoring voxel information, inter-layer connections, and detailed features. A 3D brain tumor segmentation network SDV-TUNet (Sparse Dynamic Volume TransUNet) based on an encoder-decoder architecture is proposed to achieve accurate segmentation by effectively combining voxel information, inter-layer feature connections, and intra-axis information. Volumetric data is fed into a 3D network consisting of extended depth modeling for dense prediction by using two modules: sparse dynamic (SD) encoder-decoder module and multi-level edge feature fusion (MEFF) module. The SD encoder-decoder module is utilized to extract global spatial semantic features for brain tumor segmentation, which employs multi-head self-attention and sparse dynamic adaptive fusion in a 3D extended shifted window strategy. In the encoding stage, dynamic perception of regional connections and multi-axis information interactions are realized through local tight correlations and long-range sparse correlations. The MEFF module achieves the fusion of multi-level local edge information in a layer-by-layer incremental manner and connects the fusion to the decoder module through skip connections to enhance the propagation ability of spatial edge information. The proposed method is applied to the BraTS2020 and BraTS2021 benchmarks, and the experimental results show its superior performance compared with state-of-the-art brain tumor segmentation methods. The source codes of the proposed method are available at https://github.com/SunMengw/SDV-TUNet.


Assuntos
Neoplasias Encefálicas , Humanos , Neoplasias Encefálicas/diagnóstico por imagem , Benchmarking , Neuroimagem , Semântica , Processamento de Imagem Assistida por Computador
2.
Gene ; 905: 148188, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38278336

RESUMO

Rhizoma coptidis, a Chinese herbal medicine widely used to treat various bacterial infections, has the potential to develop antibiotic substitutes to overcome the drug resistance of Vibrio alginolyticus. To study the inhibitory effect of R. coptidis on V. alginolyticus, we sequenced the transcriptomes of three groups of samples of wild-type V. alginolyticus (CK) and V. alginolyticus, which were stressed by 5 mg/mL R. coptidis for 2 h (RC_2 h) and 4 h (RC_4 h). CK was compared with RC_2 h and RC_4 h, respectively, and a total of 1565 differentially expressed genes (DEGs) (988 up-regulated and 577 down-regulated) and 1737 DEGs (1152 up-regulated and 585 down-regulated) were identified. Comparing RC_2 h with RC_4 h, 156 DEGs (114 up-regulated and 42 down-regulated) were identified. The ability of biofilm formation and motility of V. alginolyticus altered upon with different concentrations of R. coptidis. Interestingly, relative expression patterns of virulence genes appeared statistically significantly varied, upon different concentrations of R. coptidis extract. DEGs were annotated to the Gene Ontology (GO) database for function enrichment analysis and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, the results showed that the main enriched pathways, was those related to the virulence of V. alginolyticus. This study provides a new perspective for understanding the complex pathogenic mechanism of V. alginolyticus. R. coptidis could potnetially be used as alternative or complimnetary to antibiotics to treat infections after further research.


Assuntos
Antineoplásicos , Vibrioses , Humanos , Vibrio alginolyticus/genética , Virulência/genética , Vibrioses/tratamento farmacológico , Perfilação da Expressão Gênica , Transcriptoma
3.
Bioengineered ; 12(2): 12179-12190, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34783299

RESUMO

Growth factor receptor bound protein 7 (GRB7) plays an important role in regulating the growth and metastasis of ovarian cancer. Angiogenesis is the basis for the growth, invasion, and metastasis of malignant tumors. In the current study, we aimed to determine whether GRB7 plays a role in regulating angiogenesis in ovarian cancer. Immunohistochemistry on tissue microarray showed that GRB7 and platelet endothelial cell adhesion molecule-1 (PECAM-1/CD31) protein expression were positively correlated in ovarian cancer tissues. GRB7 knockdown suppressed vascular endothelial growth factor A (VEGFA) expression and reduced VEGFA secretion. The effects of GRB7-silenced SKOV-3 cells on human umbilical vein endothelial cells (HUVECs) were evaluated using a transwell cell co-culture model, which showed that knockdown of GRB7 in SKOV-3 cells suppressed HUVEC proliferation, migration, invasion, and tube formation. Moreover, knockdown of GRB7 in SKOV-3 cells downregulated the expression of proteins associated with angiogenesis, including vascular endothelial growth factor receptor-2 (VEGFR2), mitogen-activated protein kinase kinase 1 (MAP2K1/MEK1), extracellular signal-regulated kinases 1 and 2 (ERK1/2), notch receptor 1 (NOTCH1), and delta-like canonical Notch ligand 4 (DLL4) in HUVECs. In conclusion, knockdown of GRB7 in ovarian cancer cells is an attractive potential therapeutic target for the suppression of angiogenesis in ovarian cancer. GRB7 may regulate angiogenesis through VEGFA/VEGFR2 signaling and its downstream pathways.


Assuntos
Proteína Adaptadora GRB7/metabolismo , Técnicas de Silenciamento de Genes , Neovascularização Patológica/metabolismo , Neoplasias Ovarianas/irrigação sanguínea , Neoplasias Ovarianas/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Feminino , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Neoplasias Ovarianas/patologia , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo
4.
J Obstet Gynaecol ; 41(6): 977-980, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33241701

RESUMO

This study aimed to investigate the influencing factors of missed abortion during the two-child peak period in China. 220 pregnant women were divided into observation (presence of missed abortion, 100 cases) and control group (no presence of missed abortion, 120 cases). The single factor analysis of clinical data showed that, advanced age, premarital examination, genitalia abnormality, luteal insufficiency, spouse semen abnormality, mycoplasma infection, chlamydia infection, sexually transmitted diseases, perm or dyeing hair in pregnancy, radiation overload, primipara, spontaneous abortion history, smoking, drinking and overly intimate with pets had significant difference between observation and control group (p < .05). The logistic regression analysis results showed that, the advanced age, genital abnormality, luteal insufficiency, spouse sperm abnormality, pregnancy infection, primipara, spontaneous abortion history and bad life habits were the main risk factors of missed abortion. In the intervention for prevention of missed abortion, these factors should be paid more attention.Impact statementWhat is already known on this subject? There are many complex factors affecting the embryonic development and causing the missed abortion.What do the results of this study add? The advanced age, genital abnormality, luteal insufficiency, spouse sperm abnormality, pregnancy infection, primipara, spontaneous abortion history and bad life habits are the main risk factors of missed abortion.What are the implications of these findings for clinical practice and/or further research? These findings can provide a theoretical basis for the further prevention of missed abortion.


Assuntos
Aborto Retido/epidemiologia , Aborto Retido/etiologia , Aborto Induzido/efeitos adversos , Aborto Induzido/estatística & dados numéricos , Adulto , China/epidemiologia , Análise Fatorial , Política de Planejamento Familiar , Feminino , Humanos , Modelos Logísticos , Idade Materna , Gravidez , Estudos Retrospectivos , Fatores de Risco , Inquéritos e Questionários , Adulto Jovem
5.
Sensors (Basel) ; 20(3)2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32041366

RESUMO

Near-infrared (NIR) spectral sensors can deliver the spectral response of light absorbed by materials. Data analysis technology based on NIR sensors has been a useful tool for quality identification. In this paper, an improved deep convolutional neural network (CNN) with batch normalization and MSRA (Microsoft Research Asia) initialization is proposed to discriminate the tobacco cultivation regions using data collected from NIR sensors. The network structure is created with six convolutional layers and three full connection layers, and the learning rate is controlled by exponential attenuation method. One-dimensional kernel is applied as the convolution kernel to extract features. Meanwhile, the methods of L2 regularization and dropout are used to avoid the overfitting problem, which improve the generalization ability of the network. Experimental results show that the proposed deep network structure can effectively extract the complex characteristics inside the spectrum, which proves that it has excellent recognition performance on tobacco cultivation region discrimination, and it also demonstrates that the deep CNN is more suitable for information mining and analysis of big data.

6.
RSC Adv ; 8(70): 39957-39966, 2018 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-35558255

RESUMO

As a therapeutic anticancer agent, the clinical use of paclitaxel (PTX) is limited by its poor water solubility and serious adverse side effects. The targeted-specific intracellular delivery of an anticancer drug as a new therapeutic modality is promising for cancer treatment. The anticancer activity of selenium nanoparticles (SeNPs) with low toxicity and excellent activity has attracted increasing attention for use in biomedical intervention in recent years. In this study, ß-cyclodextrin (ß-CD)-folate (FA)-modified selenium nanoparticles (SeNPs) loaded with paclitaxel (PTX) (Se@ß-CD-FA@PTX) were successfully fabricated through a layer-by-layer method. The nanosystem is able to enter cancer cells through FA receptor-mediated endocytosis to achieve targeted-specific intracellular delivery. Se@ß-CD-FA@PTX was found to increase the selectivity between normal and cancer cells. The viability in MCF-7 cells was remarkably lower than in MCF 10A cells, which may promote the specific targeted delivery of Se@ß-CD-FA@PTX into MCF-7 cells. Moreover, Se@ß-CD-FA@PTX was found to enhance the cytotoxic effect on MCF-7 cells via the induction of apoptosis activation of ROS-mediated p53 and AKT signaling pathways. The results demonstrate that Se@ß-CD-FA@PTX nanoparticles provide a strategy for the design of cancer-targeted nanosystems for use in cancer therapy.

7.
Gynecol Endocrinol ; 33(4): 328-331, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27911105

RESUMO

This retrospective, cohort study examined the association between maternal pre-pregnancy body mass index (BMI), independent of glucose tolerance and adverse pregnancy outcomes in women with polycystic ovary syndrome (PCOS), for which there are few previous studies. Medical records from 2012 to 2015 at Guangzhou Women and Children's Medical Center, China were reviewed for women previously diagnosed with PCOS with normal 2-h 75-g oral glucose tolerance test (OGTT) results (n = 1249). The separate and joint effects of maternal BMI and glucose levels on pregnancy outcomes were assessed. Maternal pre-pregnancy BMI was associated with hypertensive disorders of pregnancy (HDP) (OR: 1.22, 95% CI: 1.02-1.45), preterm birth (OR: 1.49, 95% CI: 1.08-2.17), and large for gestational age (LGA) (OR: 1.69, 95% CI: 1.16-2.20). Elevated fasting glucose and maternal pre-pregnancy BMI were jointly associated with increased risks of HDP, preterm birth, and LGA. Therefore, among women with PCOS and normal glucose tolerance, maternal pre-pregnancy BMI is an independent risk factor of adverse pregnancy outcomes.


Assuntos
Índice de Massa Corporal , Intolerância à Glucose/complicações , Síndrome do Ovário Policístico/complicações , Adulto , Feminino , Intolerância à Glucose/sangue , Humanos , Hipertensão Induzida pela Gravidez/etiologia , Recém-Nascido , Síndrome do Ovário Policístico/sangue , Gravidez , Resultado da Gravidez , Estudos Retrospectivos , Fatores de Risco
8.
Int J Environ Health Res ; 16(1): 21-6, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16507478

RESUMO

A study was carried out to study the accumulative levels and dynamic changes of organochlorine pesticides in human milk in Beijing from 1982 to 1998, and the effect of prohibition and restriction on the use of DDT and BHC (666) in China in 1983. The milk samples were collected from women during the lactation period in four districts of Beijing from 1982 to 1998, in 1991, 1993 and 1998, respectively. The contents of DDT and BHC in human milk were determined according to the standard method of biology-monitoring of PR China. The average fat content of human milk was about 3% from 1982-1998 in Beijing. The average concentration of pp-DDT and op-DDT in 1985 was less than 0.10 mg/kg and remained so until 1998. The average concentration of pp'-DDT decreased from 1.80 mg/kg in 1982 to 0.24 mg/kg in 1998 and that of pp-DDE descended from 5.87 mg/kg to 1.72 mg/kg and the total concentration of DDT dropped from 7.71 mg/kg to 2.04 mg/kg. Since prohibition of organochlorine pesticides 1983, the average concentration of beta-BHC and total BHC fell respectively from 9.66 mg/kg and 10.1 mg/kg in 1983 to 1.18 mg/kg in 1998. However, the accumulative concentration of DDT and BHC was much higher than that of some foreign countries. Therefore, it was important and necessary to monitor organochlorine compounds in human milk continuously.


Assuntos
Monitoramento Ambiental , Contaminação de Alimentos/análise , Hidrocarbonetos Clorados/análise , Leite Humano/química , Resíduos de Praguicidas/análise , China , DDT/análise , Feminino , Inquéritos Epidemiológicos , Hexaclorobenzeno/análise , Humanos , Fatores de Tempo
9.
Zhonghua Yu Fang Yi Xue Za Zhi ; 39(1): 22-5, 2005 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-15794886

RESUMO

OBJECTIVE: To investigate the basic contents of organochlorine pesticides (DDT, BHC and HCB) in human milk of normal residents in Beijing urban areas. METHODS: Through continuous survey on the trend of organochlorine contents in human milk since DDT and BHC pesticides were forbidden in use in 1983, and to evaluate the effects of this program, the required lying-in women residents in urban districts for at least 5 years were enrolled in this study. All these lying-in women and also their family members were not exposed to or engaged in producing or selling organochlorine pesticides. In this study, the women chosen were giving birth to a child just after one week to 4 months. The detection method used is the national standard biological detection method. RESULTS: In 1982, the total amount of DDT and BHC contents in human milk were 6.45 mg/kg and 6.97 mg/kg, respectively, which were found the highest level in the word. The contents of organochlorine were descending apparently since the DDT and BHC pesticides were forbidden by Chinese government in 1983. According to the standards of FAO/WHO, the average intake of total DDT and beta-BHC in the infants born in 1998 was 11 and 6 microg/kg, respectively. Both of them were less than the allowable daily intake amount regulated by WHO and the Ministry of Health of Japan. CONCLUSION: The study might make clear that the basic levels of organochlorine pesticides (DDT, BHC and HCB) in human milk of normal residents and the attenuation trend of 2 pesticides cumulative levels in human body, through estimating the intake quantity of organochlorine by infants, showing that the DDT and BHC daily intake from human milk absorbed by infants, who were born after 1998, were at a safe level. It was indicated that the measure for forbidding use of DDT and BHC pesticides is contributory.


Assuntos
Hidrocarbonetos Clorados/análise , Leite Humano/química , Resíduos de Praguicidas/análise , Adulto , China , DDT/análise , Feminino , Hexaclorobenzeno/análise , Humanos , Saúde da População Urbana
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