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1.
Vet Microbiol ; 236: 108375, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31500724

RESUMO

Streptococcus suis serotype 2 (S. suis 2) is a major zoonotic pathogen. Parvulin-type peptidyl-prolyl isomerase (PrsA) in S. suis 2 is found surface-associated, pro-inflammatory and cytotoxic. To further explore the roles of PrsA in S. suis 2 infection, we constructed a prsA deletion mutant (ΔprsA) and a complemented strain (CΔprsA). The ΔprsA mutant showed increased length of bacterial chains and decreased growth. Deletion of prsA increased bacterial adhesion to host epithelial cells but with weakened invasion. The ΔprsA mutant had reduced survival in RAW264.7 macrophages and pig whole blood, and significantly attenuated in virulence to mice. All these phenotypes of the mutant could be reversed largely to the levels of its parental strain by gene complementation. Western blotting revealed that suilysin was markedly reduced both in surface-associated (SAP) and secreted fractions (SecP) of ΔprsA, which might be responsible for reduced hemolytic activity. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and enolase were significantly increased in both SAP and SecP fractions as a result of prsA deletion. Increased adhesion of the ΔprsA mutant to bEND.3 cells was prevented using polyclonal antibodies against GAPDH and enolase. Overall, we propose that S. suis 2 deploys PrsA to control translocation of important virulence factors, thereby favoring its survival in the host with enhanced pathogenicity by compromising its interactions with the host cells. Further investigation is required to find out how PrsA modulates protein translocation to benefit S. suis infection and if there are other S. suis 2 substrates of potential virulence regulated by PrsA.

2.
Zhen Ci Yan Jiu ; 44(6): 446-50, 2019 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-31368270

RESUMO

OBJECTIVE: To observe the relationship between the analgesic effect of balance acupuncture and functional changes in brain in patients with migraine without aura. METHODS: A total of 40 cases of migraine without aura were equally randomized into a headache-acupoint group and a sham-acupoint group. When acupuncture given, a filiform needle was inserted into the headache-acupoint (the midpoint of the depression region anterior to the juncture of the first and second metatarsal bones on the dorsum of the foot) or the sham point (the midpoint of the depression region anterior to the juncture site between the 3rd and 4th metatarsal joints of the dorsum of the foot) about 25-40 mm deep and manipulated for a while till the patient experienced feelings of electric shock and numbness, then withdrawn immediately. The treatment was conducted once daily for 4 weeks. The visual analogue scale (VAS) was used to evaluate the severity of pain, and the regional homogeneity (ReHo) analysis of resting state functional magnetic resonance imaging (fMRI) was used to assess changes of the spontaneous brain activity. RESULTS: After acupuncture, the analgesic effect of headache-acupoint was better than that of the sham-acupoint in both intervention stage and the follow-up stage (P< 0.05), and was also stronger in the intervention stage than in the follow-up stage (P<0.05). There was no significant difference in the analgesic effect between the intervention stage and the follow-up stage in the sham-acupoint group (P>0.05). Compared with pre-intervention, 4-weeks' intervention at the headache-acupoint showed an increase of ReHo values in the anterior cingulate gyrus, anterior central gyrus, superior orbital frontal gyrus, insula, inferior lobule, left anterior cingulate gyrus, ventral lateral nucleus and ventral posteromedial nucleus of the thalamus, pontine nucleus, cerebellar tonsils and orbital frontal inferior gyrus of the brain (P<0.05), and a decrease of ReHo values in the right brain bridge, central posterior gyrus, posterior cingulate gyrus, left central anterior gyrus, posterolateral nucleus of thalamus, and hippocampus (P<0.05), separately. In the sham-acupoint group, the ReHo value was increased in the right tongue gyrus, the left anterior lobe, the anterior cingulate gyrus and the lower occipital gyrus of the brain (P<0.05), and reduced in the left ventral posterolateral nucleus of the thalamus, separately (P<0.05). CONCLUSION: Balance acupuncture stimulation of headache acupoint has an analgesic effect in migraine patients without aura, which may be related to its effect in regulating resting state brain function of the limbic-system-dominated multiple brain regions.


Assuntos
Analgesia por Acupuntura , Transtornos de Enxaqueca , Analgésicos , Encéfalo , Epilepsia , Humanos , Imagem por Ressonância Magnética , Transtornos de Enxaqueca/terapia
3.
ACS Appl Mater Interfaces ; 11(29): 25909-25916, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31264400

RESUMO

The performance of wide-band gap perovskite solar cells has a profound impact on the multijunction tandem device efficiency. However, once bromide (Br-) has been adopted to substitute the iodide (I-) in the MAPbI3 framework, it becomes very challenging to achieve uniform and high crystalline perovskite films. Here, a synergistic effect of pseudo-halide anion thiocyanate (SCN-) and inorganic cation cesium (Cs+) on the crystallization and film formation of MA-based wide-band gap perovskite is reported. It is found that the intrinsic ability of SCN- for increasing the perovskite crystal size can make the crystallization process more tolerable to the different affinity of the initial inhomogeneous small particles. However, the introduction of SCN- usually comes along with undesired large PbI2 aggregates. By further incorporating Cs+ in the precursor solution to improve the solubility of the halide/pseudo-halide coordination to Pb2+, the formation of the aggregated PbI2 particles is successfully inhibited. As a result, uniform pinhole-free MA0.9Cs0.1PbI2Br(SCN)0.08 perovskites with a wide band gap of 1.77 eV can be achieved. The corresponding photovoltaic device exhibits a record-high fill-factor over 80% and a promising power conversion efficiency of 16.3%.

4.
Cancer Imaging ; 19(1): 39, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31217036

RESUMO

BACKGROUND: Preoperative chemotherapy is becoming standard therapy for liver metastasis from colorectal cancer, so early assessment of treatment response is crucial to make a reasonable therapeutic regimen and avoid overtreatment, especially for patients with severe side effects. The role of three non-mono-exponential diffusion models, such as the kurtosis model, the stretched exponential model and the statistical model, were explored in this study to early assess the response to chemotherapy in patients with liver metastasis from colorectal cancer. METHODS: Thirty-three patients diagnosed as colorectal liver metastasis were evaluated in this study. Diffusion-weighted images with b values (0, 200, 500, 1000, 1500, 2000 s/mm2) were acquired at 3.0 T. The parameters (ADCk, K, DDC,α, Ds and σ) were derived from three non-mono-exponential models (the kurtosis, stretched exponential and statistical models) as well as their corresponding percentage changes before and after chemotherapy. The difference in above parameters between the response and non-response groups were analyzed with independent-samples T-test (normality) and Mann-Whitney U-test (non-normality). Meanwhile, receiver operating characteristic curve (ROC) analyses were performed to assess the response to chemotherapy. RESULTS: Significantly lower values of K (the kurtosis coefficient derived from the kurtosis model) and σ (the width of diffusion coefficient distribution in the statistical model) (P < 0.05) were observed in the respond group before treatment, as well as higher ΔK and Δσ values (P < 0.05) after the first cycle of chemotherapy were also found compared with the non-respond group. ROC analyses showed the K value acquired before treatment had the highest diagnostic performance (0.746) in distinguishing responders from non-responders. Furthermore, the high sensitivity (100%) and accuracy (76.3%) from the K value before treatment was found in assessing the response of colorectal liver metastasis to chemotherapy. CONCLUSIONS: The non-mono-exponential diffusion models may be able to predict early response to chemotherapy in patients with colorectal liver metastasis.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias Hepáticas/tratamento farmacológico , Idoso , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/patologia , Feminino , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida
5.
J Appl Toxicol ; 39(9): 1283-1292, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31119768

RESUMO

Gelsemium elegans Benth., a well-known toxic herbal plant, is widely used to treat rheumatic arthritis, inflammation and other diseases. Gelsemium contains humantenmine (HMT), which is an important bioactive and toxic alkaloid. Cytochrome P450 enzymes (CYPs) play important roles in the elimination and detoxification of exogenous substances. This study aimed to investigate the roles of CYPs in the metabolism and detoxification of HMT. First, metabolic studies were performed in vitro by using human liver microsomes, selective chemical inhibitors and recombinant human CYPs. Results indicated that four metabolites, including hydroxylation and oxidation metabolites, were found in human liver microsomes and identified based on their high-resolution mass spectrum. The isoform responsible for HMT metabolism was mainly CYP3A4/5. Second, the toxicity of HMT on L02 cells in the presence of the nicotinamide adenine dinucleotide phosphate system (NADPH) was significantly less than that without NADPH system. A CYP3A4/5 activity inhibition model was established by intraperitoneally injecting ketoconazole in mice and used to evaluate the role of CYP3A4/5 in HMT detoxification. In this model, the 14-day survival rate of the mice decreased to 17% after they were intragastrically treated with HMT, along with hepatic injury and increasing alanine aminotransferase (ALT) /aspartate aminotransferase (AST) levels. Overall, CYP3A4/5 mediated the metabolism and detoxification of HMT.

6.
Stem Cells Dev ; 28(14): 954-960, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31062650

RESUMO

How hematopoietic stem cells (HSCs) maintain the balance of self-renewal and differentiation could be partially ascribed to asymmetric and symmetric division patterns. However, a simple and effective method to detect stem cell division patterns is lacking. In this study, we introduce a strategy to describe stem cells division patterns with high spatial resolution at the single-cell level. We show that the fate determinant, Numb, exhibits low expression levels in HSCs that increase upon the initiation of differentiation. Using this single-cell immunofluorescence technique, we found that HSCs mainly undergo symmetric self-renewal in the presence of only stem cell factor, but with the addition of trombopoietin this division pattern is transformed into a symmetric commitment dominant mode in vitro. In addition, our study indicated that the division pattern cannot be defined by cell size or the nuclear/cytoplasm ratio. These findings collectively demonstrate that this single-cell immunofluorescence technique provides a new biological strategy in stem cell division research, and can be more widely applied given its flexibility, easy operability, and inexpensiveness.

7.
Artigo em Inglês | MEDLINE | ID: mdl-31021778

RESUMO

Multispectral Imaging (MSI) provides a sequence of en-face fundus spectral slices and allows for the examination of structures and signatures throughout the thickness of retina to characterize diabetic retinopathy (DR) lesions comprehensively. Manual interpretation of MSI images is commonly conducted by qualitatively analyzing both the spatial and spectral properties of multiple spectral slices. Meanwhile, there exist few computer-based algorithms that can effectively exploit the spatial and spectral information of MSI images for the diagnosis of DR. We propose a new approach that can quantify the spatial-spectral features of MSI retinal images for automatic DR lesion segmentation. It combines a generalized low-rank approximation of matrices (GLRAM) with a supervised regularization term (SRT) to generate low-dimensional spatial-spectral representations using the feature vectors in all spectral slices. Experimental results showed that the proposed approach is very effective for the segmentation of DR lesions in MSI images, which suggests it as an interesting tool for assisting ophthalmologists in diagnosing, analyzing, and managing DR lesions in MSI.

8.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(2): 318-326, 2019 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-30998132

RESUMO

OBJECTIVE: To investigate the role of bone marrow vascular niche in the development of MLL-AF9 acute myeloid leukemia (AML). METHODS: Transplantation experiments were performed to establish non-radiated MLL-AF9 AML model; the half-bone immunofluorescence staining and tile-scan imaging of two-photon confocal microscopy were used to obtain the data of 3 main bone marrow niche cells; flow cytometry analysis was performed to characterize leukemia cells in different anatomical sites. RESULTS: In the early stage of MLL-AF9 AML, the proportion of leukemia cells in the metaphysis of the femur was significantly higher than that in the diaphysis. The detection of apoptosis and proliferation rate of leukemia cells showed that the percentage of leukemia cells in metaphysis significantly decreased, and the proliferation (S/G2/M phase) was also significantly more active. These different features of leukemia cells may relate with different bone marrow microenvironment. The image data of 3 major components of bone marrow niche (endothelial cells, endosteum, megakaryocytes) showed different distribution of blood vessels in metaphysis and diaphysis. Furtherly comparing the spatial distance between leukemia cells and endothelial cells, endosteum, megakaryocytes indicated that leukemia cells are closer to the blood vessels, suggesting the important role of blood vessels in the development of leukemia. Glucose uptake assays and intracellular ROS detection showed that the supportive role of blood vessels for leukemia cells did not related with nutrient metabolism pathway. CONCLUSION: The vascular niche plays an important role in the development of leukemia, and does not relate with the transport of nutrients and the elimination of metabolic waste, instead, which may relate with perivascular cytokines or other vascular functions.


Assuntos
Medula Óssea , Leucemia Mieloide Aguda , Doença Aguda , Apoptose , Células da Medula Óssea , Humanos , Proteína de Leucina Linfoide-Mieloide , Proteínas de Fusão Oncogênica
9.
Nanoscale ; 11(18): 8736-8743, 2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31020987

RESUMO

The quality of solution-processed zinc oxide (ZnO) nanoparticles (NPs) is often correlated with their photoluminescence (PL) spectral characteristics. However, the reported PL spectral characteristics lack consistency and remain controversial. Here we report that "defect-emission free" PL spectra can even be obtained in thin films composed of as-synthesized ZnO NPs. It is found that both the PL spectral line-shape and intensity are extremely sensitive to nitrogen and oxygen. By conducting time-dependent PL (t-PL) and photothermal deflection spectroscopy (PDS) measurements under vacuum and different gases, it is proposed that both inert (N2) and reactive (O2) molecules can be absorbed on the ZnO NP surface and induce charge transfer (CT). The CT states induced by N2 are non-radiative which significantly reduces the band emission. Whereas the CT states induced by O2 are radiative at the visible region, and the exciton transfer is efficient which increases the overall PL quantum yield. Owing to such effects, the previously reported correlation between defects and PL emission becomes questionable and needs to be revisited. Particularly, the visible emission from the ZnO NPs is proved to be facilitated by external effects, instead of direct recombination from defect states.

10.
Artigo em Inglês | MEDLINE | ID: mdl-30908259

RESUMO

Chromosome classification is critical for karyotyping in abnormality diagnosis. To expedite the diagnosis, we present a novel method named Varifocal-Net for simultaneous classification of chromosome's type and polarity using deep convolutional networks. The approach consists of one global-scale network (G-Net) and one localscale network (L-Net). It follows three stages. The first stage is to learn both global and local features. We extract global features and detect finer local regions via the G-Net. By proposing a varifocal mechanism, we zoom into local parts and extract local features via the L-Net. Residual learning and multi-task learning strategies are utilized to promote high-level feature extraction. The detection of discriminative local parts is fulfilled by a localization subnet of the GNet, whose training process involves both supervised and weakly-supervised learning. The second stage is to build two multi-layer perceptron classifiers that exploit features of both two scales to boost classification performance. The third stage is to introduce a dispatch strategy of assigning each chromosome to a type within each patient case, by utilizing the domain knowledge of karyotyping. Evaluation results from 1909 karyotyping cases showed that the proposed Varifocal-Net achieved the highest accuracy per patient case (%) of 99.2 for both type and polarity tasks. It outperformed state-of-the-art methods, demonstrating the effectiveness of our varifocal mechanism, multi-scale feature ensemble, and dispatch strategy. The proposed method has been applied to assist practical karyotype diagnosis.

11.
Medicine (Baltimore) ; 98(8): e14519, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30813154

RESUMO

To understand the risks associated with aplastic anemia (AA) in 4 cities of Zhejiang Province, China, with special focus on the joint contributions of multiple risks.Based on an Electronic Data Capture (EDC), a case control study was carried out. Data regarding socio-demographic, diseases history, living habits, and exposures to toxic substances, etc., were collected through survey questionnaires. t Test, chi-square test, or non-parametric rank sum test, and univariate and multivariate Logistic regression analysis were conducted to analyze data.The univariate logistic regression analysis results indicated that among all study participants (n = 1802), AA was associated with over 30 risks, in terms of their individual behaviors, daily and environmental exposures, diseases history, and family history. Multivariate logistic regression analysis further confirmed that the independent risks related to AA included presence of chemical factory within 3 km of living residence (odds ratio [OR] = 8.73, 95% CI: 1.42-53.74, P = .019), living in a newly decorated house/apartment (OR = 25.37, 95% CI: 4.44-144.81, P < .001), vegetarian diet (OR = 131.60, 95% CI: 3.45-5020.16, P = .009), preference of sugar (OR = 89.38, 95% CI: 7.22-1106.44, P < .001), preference of oily food (OR = 55.68, 95% CI: 5.12-605.26, P = .001), drinking lake water or pond water (OR = 58.05, 95% CI: 3.21-1049.81, P < .001), habit of staying up late (OR = 11.87, 95% CI: 3.43-41.02, P < .001), infection history (OR = 10.08, 95% CI: 2.75-36.93, P < .001). Result of receiver operating characteristic curve (ROC) analysis on the joint contribution of multiple risks indicated that AA was 13.835 times likely to occur when exposed to ≥1 risks than those exposed to 0 risks (95% CI: 9.995-19.149).Our study results demonstrated a comprehensive epidemiological pattern, in which the joint contributions of individual inherited health status, environment exposure, and individual behaviors lead to the occurrence of AA.


Assuntos
Anemia Aplástica/etiologia , Medição de Risco/métodos , Adolescente , Adulto , Idoso , Anemia Aplástica/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , China/epidemiologia , Exposição Ambiental/efeitos adversos , Feminino , Comportamentos Relacionados com a Saúde/etnologia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Inquéritos e Questionários , Adulto Jovem
12.
Ying Yong Sheng Tai Xue Bao ; 30(2): 420-428, 2019 Feb 20.
Artigo em Chinês | MEDLINE | ID: mdl-30915792

RESUMO

We examined the effects of warming (+5 ℃) and reduced natural precipitation (-50%) on nutrient status and physiological indices of Cunninghamia lanceolata seedlings during winter and summer in subtropical China. The results showed that seasonal changes in temperature and precipitation caused the seasonal differences in plant nutrient contents and metabolites levels. Contents of carbon, nitrogen, phosphorus, and potassium in leaves in winter were significantly higher than those in summer. In summer, reduced precipitation and warming had no significant effects on antioxidant enzyme activities in C. lanceolata leaves. In winter, superoxide dismutase and peroxidase activities in the leaves significantly decreased with reduced precipitation by 20.7% and 17.8%. Additionally, in winter, warming treatment significantly increased non-enzymatic ascorbic acid content by 132.5%. Carbon content decreased, whereas proline accumulation and nitrogen content increased under stress induced by combined warming and reduced precipitation in winter. However, carbon content increased by 3.3% under the treatment of simultaneous warming and reduced precipitation in summer. In addition, combined warming and reduced precipitation had no significant effects on the antioxidant system irrespective of the season. In conclusion, the adaptation mechanism of C. lanceolata to warming in summer might be different from that in winter. The changes in nutrient contents in C. lanceolata leaves were more sensitive to stress induced by combined warming and reduced precipitation. Nutrient demand and supply and seasonal changes in plant responses under climate change scenarios should be considered for better managing forest plantations and improving plant productivity.


Assuntos
Cunninghamia , China , Nutrientes , Estações do Ano , Plântula
14.
Huan Jing Ke Xue ; 40(1): 149-156, 2019 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-30628270

RESUMO

Based on the precipitation samples and meteorological data simultaneously collected during individual precipitation events at the Gulang (2085 m a.s.l.) and Anyuan stations (2700 m a.s.l.) in Gulang, this article analyzes the temporal variation and local meteroic water lines and discusses the relationship between precipitation stable isotopes and temperature and precipitation and relative humidity. The results show that:① Gulang and Anyuan have higher δ18O values in summer and autumn and lower δ18O values in spring and winter, respectively; ② The vaule of δ18O decreases with increasing altitude, while the value of the d-excess increases, reflecting the gradual depletion of stable isotopes of precipitation when the air mass is rising along the slope; ③ The slope and intercept of the local meteroic water lines deviate from that of the global meteroic water lines, showing that they may also be affected by local water vapor recirculation, except for the dry environment and strong evaporation effect; and ④ The temperature effect of Gulang in the low-altitude area is more significant than that of the Anyuan station and the Gulang River Basin does not show a precipitation effect. It has been proven that precipitation is not the fundamental factor determining the δ18O of the precipitation in arid areas. The results of this study are helpful to further understand the water circulation mechanism in the Gulang River Basin.

15.
ACS Appl Mater Interfaces ; 11(6): 6126-6135, 2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30668090

RESUMO

Depth-dependent growth of perovskite crystals remains challenging for high-performance perovskite solar cells made by a two-step spin-coating method. Effective morphology engineering approaches that enable depth-independent perovskite crystals growth and facile characterization technique to monitor subtle yet influential accompanying changes are urgently required. Here, a porous and intercrossed PbI2-(CsI)0.15 nanorods scaffold is prepared by integrating CsI incorporation with toluene dripping in ambient air, and the underlying mechanism is uncovered. With this porous scaffold and moisture-assisted thermal annealing, depth-independent growth of FA0.85Cs0.15PbI3 is achieved, as evidenced in the photoluminescent (PL) spectra acquired by exciting the perovskite film from the top and bottom individually. It is of broad interest that PL spectroscopy is demonstrated as a sensitive technique to monitor the depth-dependent growth of perovskite. Moreover, the resulting inverted planar FA0.85Cs0.15PbI3 perovskite solar cells deliver an efficiency of 16.85%, along with superior thermal and photostability. By incorporating 2% large-sized diammonium cation, propane-1,3-diammonium, the efficiency is further increased to 17.74%. Our work not only proposes a unique porous PbI2-(CsI)0.15 nanorods scaffold to achieve high-quality perovskite films in a two-step method but also highlights the distinctive advantage of PL spectroscopy in monitoring the depth-dependent quality of perovskite films.

16.
Clin Infect Dis ; 69(2): 379-380, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-30615094
17.
Med Phys ; 46(3): 1218-1229, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30575046

RESUMO

PURPOSE: Segmentation of pulmonary nodules is critical for the analysis of nodules and lung cancer diagnosis. We present a novel framework of segmentation for various types of nodules using convolutional neural networks (CNNs). METHODS: The proposed framework is composed of two major parts. The first part is to increase the variety of samples and build a more balanced dataset. A conditional generative adversarial network (cGAN) is employed to produce synthetic CT images. Semantic labels are generated to impart spatial contextual knowledge to the network. Nine attribute scoring labels are combined as well to preserve nodule features. To refine the realism of synthesized samples, reconstruction error loss is introduced into cGAN. The second part is to train a nodule segmentation network on the extended dataset. We build a three-dimensional (3D) CNN model that exploits heterogeneous maps including edge maps and local binary pattern maps. The incorporation of these maps informs the model of texture patterns and boundary information of nodules, which assists high-level feature learning for segmentation. Residual unit, which learns to reduce residual error, is adopted to accelerate training and improve accuracy. RESULTS: Validation on LIDC-IDRI dataset demonstrates that the generated samples are realistic. The mean squared error and average cosine similarity between real and synthesized samples are 1.55 × 10 - 2 and 0.9534, respectively. The Dice coefficient, positive predicted value, sensitivity, and accuracy are, respectively, 0.8483, 0.8895, 0.8511, and 0.9904 for the segmentation results. CONCLUSIONS: The proposed 3D CNN segmentation framework, based on the use of synthesized samples and multiple maps with residual learning, achieves more accurate nodule segmentation compared to existing state-of-the-art methods. The proposed CT image synthesis method can not only output samples close to real images but also allow for stochastic variation in image diversity.


Assuntos
Diagnóstico por Computador , Processamento de Imagem Assistida por Computador/métodos , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Redes Neurais (Computação) , Tomografia Computadorizada por Raios X/métodos , Bases de Dados Factuais , Diagnóstico por Computador/métodos , Humanos , Nódulos Pulmonares Múltiplos/patologia
18.
Dev Comp Immunol ; 90: 121-129, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30227217

RESUMO

Peptidoglycan is the key component forming the backbone of bacterial cell wall. It can be recognized by a group of pattern recognition receptors, known as peptidoglycan recognition proteins (PGRPs) in insects and higher animals. PGRPs may serve as immune receptors or N-acetylmuramoyl-L-alanine amidases (EC 3.5.1.28). Here, we report the characterization of a short PGRP, PGRP-S1, from the oriental armyworm, Mythimna separata. MsePGRP-S1 cDNA encodes a protein of 197 amino acids (aa) with a PGRP domain of about 150 aa. MsePGRP-S1 was expressed in several tissues of naïve larvae, including hemocytes, midgut, fat body and epidermis. Bacterial challenges caused variable changes in different tissues at the mRNA level. The recombinant protein bound strongly to Staphylococcus aureus and purified peptidoglycans from Staphylococcus aureus and Bacillus subtilis. It can inhibit the growth of gram-negative and gram-positive bacteria by disrupting bacterial surface. It can degrade peptidoglycans from Escherichia coli and Staphylococcus aureus. Taken together, these data demonstrate that M. separata PGRP-S1 is involved in defending against bacteria.


Assuntos
Bacillus subtilis/fisiologia , Proteínas de Transporte/genética , Hemócitos/fisiologia , Proteínas de Insetos/genética , Receptores de Reconhecimento de Padrão/genética , Infecções Estafilocócicas/imunologia , Staphylococcus aureus/fisiologia , Animais , Antibacterianos/metabolismo , Proteínas de Transporte/metabolismo , Clonagem Molecular , Imunidade Inata , Proteínas de Insetos/metabolismo , Lepidópteros/imunologia , Peptidoglicano/metabolismo , Receptores de Reconhecimento de Padrão/metabolismo , Proteínas Recombinantes/genética
19.
Transbound Emerg Dis ; 66(2): 1044-1048, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30548172

RESUMO

Salmonella enterica Newport (S. Newport), with phylogenetic diversity feature, contributes to significant public health concerns. Our previous study suggested that S. Newport from multiple animal-borne routes, with distinct antibiotic resistant pattern, might transmit to human. However, their genetic information was lacking. As a complement to the earlier finding, we investigate the relationship between each other among the hosts, sources, genotype and antibiotic resistance in S. Newport. We used the multilocus sequence typing (MLST) in conjunction with minimum inhibitory concentration of 16 antibiotics of globally sampled 1842 S. Newport strains, including 282 newly contributed Chinese strains, to evaluate this association. Our analysis reveals that sequence types (STs) are significantly associated with different host sources, including livestock (ST45), birds (ST5), contaminated water and soil (ST118), reptiles (ST46) and seafood (ST31). Importantly, ST45 contained most of (344/553) the multi-drug resistance (MDR) strains, which were believed to be responsible for human MDR bacterial infections. Chinese isolates were detected to form two unique lineages of avian (ST808 group) and freshwater animal (ST2364 group) origin. Taken together, genotyping information of S. Newport could serve to improve Salmonella source-originated diagnostics and guide better selection of antibiotic therapy against Salmonella infections.


Assuntos
Salmonelose Animal/epidemiologia , Infecções por Salmonella/epidemiologia , Salmonella enterica/genética , Salmonella enterica/isolamento & purificação , Animais , Farmacorresistência Bacteriana Múltipla , Genes Bacterianos , Genótipo , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Filogenia , Infecções por Salmonella/microbiologia , Salmonelose Animal/microbiologia , Sorogrupo
20.
J Magn Reson Imaging ; 2018 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-30447032

RESUMO

BACKGROUND: Non-monoexponential diffusion models are being used increasingly for the characterization and curative effect evaluation of hepatocellular carcinoma (HCC). But the fitting quality of the models and the repeatability of their parameters have not been assessed for HCC. PURPOSE: To evaluate kurtosis, stretched exponential, and statistical models for diffusion-weighted imaging (DWI) of HCC, using b-values up to 2000 s/mm2 , in terms of fitting quality and repeatability. STUDY TYPE: Prospective. POPULATION: Eighteen patients with HCC. FIELD STRENGTH/SEQUENCE: Conventional and DW images (b = 0, 200, 500, 1000, 1500, 2000 s/mm2 ) were acquired at 3.0T. ASSESSMENT: The parameters of the kurtosis, stretched exponential, and statistical models were calculated on regions of interest (ROIs) of each lesion. STATISTICAL TESTS: The fitting quality was evaluated through comparing the fitting residuals produced on the average data of ROI between different models using a paired t-test or Wilcoxon rank-sum test. Repeatability of the fitted parameters at the median values on the voxelwise data of ROI was assessed using the within coefficient of variation (WCV), the intraclass correlation coefficient (ICC), and the 95% Bland-Altman limits of agreements (BA-LA). The repeatability was divided into four levels: excellent, good, acceptable, and poor, referring to the values of ICC and WCV. RESULTS: Among three models, the stretched exponential model provided the best fit to HCC (P < 0.05), whereas the statistical model produced the largest fitting residuals (P < 0.05). The repeatability of K from the kurtosis model was excellent (ICC 0.915; WCV 8.79%), while the distributed diffusion coefficient (DDC) from the stretched model was just acceptable (ICC 0.477; WCV 27.83%). The repeatability was good for other diffusion-related parameters. DATA CONCLUSION: Considering the model fit and repeatability, the kurtosis and stretched exponential models are the preferred models for the description of the DW signals of HCC with respect to the statistical model. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018.

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