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1.
Opt Express ; 27(22): 32210-32216, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31684437

RESUMO

Adaptive moment estimation (Adam) is a popular optimization method to estimate large-scale parameters in neural networks. This paper proposes the first use of Adam algorithm to fast and stably converge large-scale tap coefficients of polynomial nonlinear equalizer (PNLE) for 129-Gbit/s PAM8-based optical interconnects. PNLE is one of simplified Volterra nonlinear equalizer for making a trade-off between complexity and performance. Different from serial least-mean square (LMS) adaptive algorithm, Adam algorithm is a parallel processing algorithm, which can obtain globally optimal tap coefficients without being trapped in locally optimal tap coefficients. Timing error is one of the main obstacles to the PAM systems with high baud rate and high modulation order. Owing to parallel processing and global optimization, Adam algorithm has much better performance on resisting the timing error, which can achieve faster, more-stable and lower-MSE convergence compared to LMS adaptive algorithm. In conclusion, Adam algorithm shows great potential for converging the tap coefficients of PNLE in PAM8-based optical interconnects.

2.
Environ Res ; 179(Pt B): 108828, 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31704496

RESUMO

Polybrominated diphenyl ethers (PBDEs) were listed in the Stockholm Convention due to their persistent and toxic nature. In utero exposure to PBDEs might affect fetal development as it is sensitive when exposed to even low dose of xenobiotic substances during the pregnancy. In this study, a multi-centre human biomonitoring study of tri-to hexa-BDEs was conducted in three Chinese cities using 60 colostrum samples from local residents. The patterns and influencing factors, correlation with the birth outcome, and potential health risks during the breastfeeding of tri-to hexa-BDEs in the colostrum samples were assessed. The median concentration of tri-to hexa-BDEs was 9.1 (Interquartile range: 3.1-19.5) ng g-1 lipid weight, and BDE-153 contributed 68% of the detected PBDEs. The PBDE levels were mostly associated with maternal age and drinking water sources, while correlations with other factors including weight gain, BMI, parity and the number of aborted pregnancies was not significant. The level of BDE-28 was positively correlated with the birth weight, while the BDE-99 was positively correlated with the head circumference, using multilinear regression. For the total hazard quotients, 60% of the infants have an estimated value higher than 1, showed potential chronic hazard for future development and possible adverse health effects to the babies from the exposure to PBDE congeners. Alternative food source seems to have a lower risk for neonates than the colostrum, but the advantages of breastfeeding undoubtedly outweigh the risks and potential adverse health effects caused by environmental PBDEs and other xenobiotic chemical exposure.

3.
Am J Surg Pathol ; 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31609782

RESUMO

Primary adrenal diffuse large B-cell lymphoma (PA-DLBCL) is a rare subtype of extranodal DLBCL. Because of the rarity of this disease, its morphologic and genetic features are not comprehensively studied. Here, we systematically reviewed the clinicopathologic features of 42 cases of PA-DLBCL from our institution and investigated the frequency of MYD88 L265P and CD79B (exon 5) mutation in 29 eligible cases using Sanger sequencing. Clinically, PA-DLBCL was predominant in elderly male patients with advanced clinical stage and poor outcomes. Morphologically, the tumors often showed a sinusoidal and/or cohesive pattern with condensed chromatin and inconspicuous nucleolus which mimicked neuroendocrine carcinoma. Moreover, increased Reed-Sternberg-like cells were observed frequently. These confounding morphologic manifestations may lead to misdiagnosis. Genetically, PA-DLBCL harbored a high prevalence of MYD88 L265P (24%) and CD79B mutations (52%) which may be involved in lymphomagenesis. The CD79B mutation was significantly associated with a worse prognosis. A novel Histo-Molecular Classification system (4 categories) was proposed based on correlation with genetic changes. Generally, the neuroendocrine carcinoma-like type was associated with CD79B mutation, whereas the RS-like cell type indicated MYD88 L265P. The biphasic type was correlated with coexisting mutations of MYD88 and CD79B, whereas the common type implied no mutation. Furthermore, the common type showed significantly better survival. In conclusion, the proposed new category system could indicate the genetic changes as well as facilitate risk stratification to guide treatment and predict prognosis. Although this study augmented our understanding of PA-DLBCL, further analysis is required to validate our results and extend them to extranodal DLBCL at other sites.

4.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 44(8): 885-891, 2019 Aug 28.
Artigo em Chinês | MEDLINE | ID: mdl-31570675

RESUMO

OBJECTIVE: To evaluate the impact of admission diagnosis on seizure outcome in patients with autoimmune epilepsy (AE).
 Methods: We conducted a retrospective study on 40 AE patients at Department of Neurology, Xiangya Hospital, Central South University from Jan. 1st, 2017 to Nov. 21st, 2018. According to their admission diagnosis, these patients were further assigned into 2 groups: An AE diagnosed group and an AE undiagnosed group. Demographic data, clinical characteristics, cerebrospinal fluid (CSF), electroencephalogram, and brain imaging were compared between the 2 groups. Favorable seizure outcome was defined as >50% reduction of seizure frequency at the first follow-up. The impact of admission diagnosis on seizure outcome of AE patients was analyzed.
 Results: The ages of 40 AE patients were (33.23±16.41) years, comprising 19 males and 21 females. No significant difference was found between the AE diagnosed group and the AE undiagnosed group in gender, age, central nervous system-specific Ab profile, CSF, and brain imaging. Duration of symptom onset to Ab detection was significantly longer in the AE undiagnosed group than that in the AE diagnosed group (P<0.01). Duration of symptom onset to immunotherapy was also significantly longer in the AE undiagnosed group than that in the AE diagnosed group (P<0.001). There were more patients with favorable seizure outcome in the AE diagnosed group than the AE undiagnosed group (P<0.05).
 Conclusion: Admission diagnosis for patients with AE is associated with seizure outcome after immunotherapy. For adult-onset epilepsy or epilepsy with unknown etiology, the diagnosis of AE should be considered. Early diagnosis of AE and prompt initiation of immunosuppressive treatment are crucial to increase the likelihood of achieving favorable seizure outcome.


Assuntos
Epilepsia , Adolescente , Adulto , Eletroencefalografia , Feminino , Humanos , Imunoterapia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Convulsões , Adulto Jovem
5.
Opt Express ; 27(14): 19615-19623, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31503718

RESUMO

On-chip microlasers are desirable to meet the different control requirements and unique demands in different application scenarios. In this work, we obtained the on-chip microlaser by printing pixelated CdSe/ZnS colloidal quantum dots (CQDs), incorporating the quantum dot self-assembly mechanism and the external cavity-free configuration. The spectral purity of the microlaser can be significantly improved by slightly blending polymer into the CQD matrix. The quasitoroid profile was gradually changed to microdisks as the polystyrene (PS) concentration increased from 0 wt.% to 10 wt.%. Specially, when the PS solution varied from 0 wt.% to 1 wt.%, the lasing threshold of 1.4 µJ/mm2 was increased up to 14 µJ/mm2, meanwhile the emission wavelength range showed a 25 nm blue-shift approximately. The easy printing technologies and the low-cost polymer blending method employed in the obtained microlasers will further facilitate the development of printing photonics and electronics, especially in the high-performance microlaser displays and high-precision sensors.

6.
Opt Express ; 27(15): 20358-20372, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31510131

RESUMO

Compared to glass walls with a positive curvature, those with a negative curvature have been proven to have stronger confinement of light. Therefore, we change the multi-layered air holes in a photonic crystal fiber into several negative curvature tubes. As a result, the confinement medium is shifted from a low-index cladding material into a special structure. The theoretical analysis shows that each vector eigenmode has a corresponding threshold value for the outer tube thickness. It means that we can confine the target modes and filter the unnecessary modes by shifting the outer tube thickness. After substantial investigation on this fiber, we obtain the appropriate values for each structural parameter and then fabricate this negative curvature ring-core fiber under the guidance of the simulation results. Firstly, we draw the central cane under vacuum condition, then stack the cane and six capillaries to form the preform, and finally draw the ring-core fiber by using vacuumization method. The fiber test experiment indicates that the fiber length should be at least 15 m∼20 m to form the donut facula, and the tested losses of OAM+1,1, OAM+2,1, OAM+3,1, and OAM+4,1 are 0.30 dB/m, 0.36 dB/m, 0.37 dB/m, and 0.42 dB/m, respectively.

7.
J Cancer Res Clin Oncol ; 145(10): 2529-2539, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31485768

RESUMO

PURPOSE: This study aimed to determine the potential of positron emission tomography/computed tomography (PET/CT) in replacing routine bone-marrow biopsies (BMB) in newly diagnosed extranodal natural killer/T-cell lymphoma (ENKTCL). METHODS: Newly diagnosed patients underwent PET/CT imaging and routine BMB to assess bone/bone marrow involvement (BMI). Clinical stage and treatment plan were determined, and survival was compared. RESULTS: In a total of 101 patients, 78 were diagnosed as stage I/II and 23 as stage III/IV without using the BMB results. No BMB-positive patients were identified in stages I/II, and therefore, the BMB results did not alter the stage and treatment choice in any patients. The sensitivity and specificity of focal skeletal PET/CT lesion(s) in assessing BMI was 100% and 92.8%, respectively, taking routine BMB as the reference standard. The overall survival (OS) and progression-free survival (PFS) of BMB-positive patients was significantly inferior (P = 0.0011 and 0.0465, respectively, in advanced-stage patients; both P < 0.0001 in all patients), and this was corroborated by the PET/CT findings (P = 0.0006 and 0.0116, respectively, in advanced-stage patients; both P < 0.0001 in all patients). CONCLUSIONS: Based on the results, PET/CT demonstrated satisfactory predictive performance in terms of staging and prognosis in ENKTCL. BMB did not influence staging and treatment in newly diagnosed ENKTCL, and routine non-targeted BMB is not obligatory for early stage patients undergoing PET/CT. Targeted BMB is recommended to confirm BMI in advanced-stage patients.


Assuntos
Medula Óssea/diagnóstico por imagem , Medula Óssea/patologia , Linfoma Extranodal de Células T-NK/diagnóstico , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Adolescente , Adulto , Idoso , Biomarcadores , Biópsia , Feminino , Humanos , Linfoma Extranodal de Células T-NK/mortalidade , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons/métodos , Prognóstico , Modelos de Riscos Proporcionais , Sensibilidade e Especificidade , Análise de Sobrevida , Adulto Jovem
8.
Environ Int ; 133(Pt A): 105133, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31520960

RESUMO

Endocrine-disrupting chemicals (EDCs) have received significant concern, since they ubiquitously exist in the environment and are able to induce adverse health effects on human and wildlife. Increasing evidence shows that the glucocorticoid receptor (GR) and the mineralocorticoid receptor (MR), members of the steroid receptor subfamily, are potential targets for EDCs. GR and MR mediate the actions of glucocorticoids and mineralocorticoids, respectively, which are two main classes of corticosteroids involved in many physiological processes. The effects of EDCs on the homeostasis of these two classes of corticosteroids have also gained more attention recently. This review summarized the effects of environmental GR/MR ligands on receptor activity, and disruption of corticosteroid homeostasis. More than 130 chemicals classified into 7 main categories were reviewed, including metals, metalloids, pesticides, bisphenol analogues, flame retardants, other industrial chemicals and pharmaceuticals. The mechanisms by which EDCs interfere with GR/MR activity are primarily involved in ligand-receptor binding, nuclear translocation of the receptor complex, DNA-receptor binding, and changes in the expression of endogenous GR/MR genes. Besides directly interfering with receptors, enzyme-catalyzed synthesis and prereceptor regulation pathways of corticosteroids are also important targets for EDCs. The collected evidence suggests that corticosteroids and their receptors should be considered as potential targets for safety assessment of EDCs. The recognition of relevant xenobiotics and their underlying mechanisms of action is still a challenge in this emerging field of research.

9.
Theranostics ; 9(20): 5956-5975, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31534531

RESUMO

Mesenchymal stem cell-derived exosomes (MSC-Exo) have robust anti-inflammatory effects in the treatment of neurological diseases such as epilepsy, stroke, or traumatic brain injury. While astrocytes are thought to be mediators of these effects, their precise role remains poorly understood. To address this issue, we investigated the putative therapeutic effects and mechanism of MSC-Exo on inflammation-induced alterations in astrocytes. Methods: Lipopolysaccharide (LPS)-stimulated hippocampal astrocytes in primary culture were treated with MSC-Exo, which were also administered in pilocarpine-induced status epilepticus (SE) mice. Exosomal integration, reactive astrogliosis, inflammatory responses, calcium signaling, and mitochondrial membrane potentials (MMP) were monitored. To experimentally probe the molecular mechanism of MSC-Exo actions on the inflammation-induced astrocytic activation, we inhibited the nuclear factor erythroid-derived 2, like 2 (Nrf2, a key mediator in neuroinflammation and oxidative stress) by sgRNA (in vitro) or ML385 (Nrf2 inhibitor) in vivo. Results: MSC-Exo were incorporated into hippocampal astrocytes as well as attenuated reactive astrogliosis and inflammatory responses in vitro and in vivo. Also, MSC-Exo ameliorated LPS-induced aberrant calcium signaling and mitochondrial dysfunction in culture, and SE-induced learning and memory impairments in mice. Furthermore, the putative therapeutic effects of MSC-Exo on inflammation-induced astrocytic activation (e.g., reduced reactive astrogliosis, NF-κB deactivation) were weakened by Nrf2 inhibition. Conclusions: Our results show that MSC-Exo ameliorate inflammation-induced astrocyte alterations and that the Nrf2-NF-κB signaling pathway is involved in regulating astrocyte activation in mice. These data suggest the promising potential of MSC-Exo as a nanotherapeutic agent for the treatment of neurological diseases with hippocampal astrocyte alterations.

10.
Sensors (Basel) ; 19(19)2019 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-31561639

RESUMO

Point cloud is a widely used 3D data form, which can be produced by depth sensors, such as Light Detection and Ranging (LIDAR) and RGB-D cameras. Being unordered and irregular, many researchers focused on the feature engineering of the point cloud. Being able to learn complex hierarchical structures, deep learning has achieved great success with images from cameras. Recently, many researchers have adapted it into the applications of the point cloud. In this paper, the recent existing point cloud feature learning methods are classified as point-based and tree-based. The former directly takes the raw point cloud as the input for deep learning. The latter first employs a k-dimensional tree (Kd-tree) structure to represent the point cloud with a regular representation and then feeds these representations into deep learning models. Their advantages and disadvantages are analyzed. The applications related to point cloud feature learning, including 3D object classification, semantic segmentation, and 3D object detection, are introduced, and the datasets and evaluation metrics are also collected. Finally, the future research trend is predicted.

11.
Sci Total Environ ; 697: 134040, 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31476509

RESUMO

Polybrominated biphenyls (PBBs) were widely used as additive brominated flame retardants. Their hydroxylated products (OH-PBBs) have been detected frequently in various marine mammals, causing an increased health risk. Till now, there lacks information on the potential disruption of OH-PBBs toward thyroid hormone receptor (TR) and the molecular characteristics of their interactions remain largely unknown. We herein in vitro and in silico evaluated the disrupting effect of 3,3',5,5'-tetrabromobiphenyl (BB80) and its metabolite 2,2'-dihydroxy- 3,3',5,5'-tetrabromobiphenyl (OH-BB80) toward human TR. The recombinant human TRß two-hybrid yeast assay reveals the moderate antagonistic activity of OH-BB80 with IC20 at 2 µmol/L, while BB80 shows no agonistic or antagonistic activity. OH-BB80 binds at the binding cavity of TRß ligand binding domain (LBD) and forms one hydrogen bond with Phe272. Electrostatic interactions and hydrophobic interactions contribute much to their interactions. The binding of OH-BB80 quenches the intrinsic fluorescence of TRß LBD at static quenching mode. Our study extends knowledge on the endocrine disrupting effect of OH-PBBs and suggests the full consideration of the biotransformation for further health risk assessment of PBBs and related structurally similar emerging contaminants.

12.
Environ Pollut ; 254(Pt A): 112900, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31394347

RESUMO

Breast milk, especially colostrum, is not just a source of nutrients and immune factors for the newborn, but also accumulates environmental persistent pollutants and its diverse microbes affect the early colonization of the newborn's gut. Little is known about associations between environmental pollutants and the microbial composition of human colostrum. We assessed the influence of hexachlorocyclohexane (HCH), a persistent organic pollutant (POP), in colostrums on the microbial composition of human colostrum samples. HCH concentrations in 89 colostrum samples collected from a population living on the easternmost island of China were measured via gas chromatography equipped with mass spectrometer (GC-MS), HCH exposure risks for infants via dietary intake of breast milk were assessed, and for 29 colostrum samples the microbiota were profiled using 16S rRNA gene pyrosequencing to assess the association with HCH exposure levels. Our study confirmed high colostrum exposure levels of total HCHs (12.19 ±â€¯13.68 µg L-1) in this Chinese population. We predominantly identified Proteobacteria (67.6%) and Firmicutes (25.1%) in colostrum and microbial diversity at the genus level differed between samples with different HCH levels; e.g., Pseudomonas which contains several HCH degrading strains was found in significantly higher abundance in γ-HCH rich samples. Also, microbes that were statistically significantly associated with HCH levels were also highly correlated with each other (false discovery rate (FDR)<0.01) and clustered in network analysis. Microbial diversity is associated with HCH levels in human colostrum and these associations might be attributable to their HCH degrading ability. These finding provide first insights into the role that environmental persistent pollutants may play in the microbial composition of human colostrum and the colonization of the infant gut.

13.
Environ Sci Technol ; 53(19): 11458-11466, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31452367

RESUMO

Short-chain chlorinated paraffins (SCCPs) and medium-chain chlorinated paraffins (MCCPs) are high-production-volume persistent and toxic industrial chemicals found ubiquitously in various environmental matrices. However, information is scarce regarding human internal exposure. The congener-specific SCCP and MCCP levels in matched maternal serum (n = 31), umbilical cord serum (n = 31), and placenta (n = 31) were studied to investigate the maternal-placenta-fetus distribution and the placental transport mechanisms of SCCPs and MCCPs. The results indicated that lower chlorinated and shorter carbon chain CPs were efficiently transported across placenta compared to highly chlorinated and longer carbon chain CPs. Meanwhile, ∑MCCP concentration followed the order of maternal sera > placentas > cord sera. The cord/maternal concentration fraction ratios (RCM) of CPs exhibited similar values from C10 to C14, and then from C15, a decreasing trend was observed with increasing carbon chain length. The log-normalized maternal SCCP concentrations were positively correlated (P < 0.01) with that in the cord, suggesting fetus exposure to SCCPs during pregnancy. Furthermore, the placenta/maternal concentration fraction ratio (RPM) values for MCCPs were relatively higher than those for SCCPs, demonstrating that MCCPs were not efficiently transported and effectively retained in placenta tissues. These findings provide a better understanding of the maternal-fetal transmission and neonatal exposure to CPs.

14.
Chirality ; 31(10): 870-878, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31407830

RESUMO

Perfluorooctane sulfonate (PFOS) is one of the most frequently detected perfluoroalkyl substances in environmental and human samples. Previous studies have shown that nonracemic PFOS in biological samples can be used as a marker of PFOS exposure sources. In recent years, supercritical fluid chromatography (SFC) has emerged as a powerful method to separate chiral compounds. In this study, a method of perfluoro-1-methylheptane sulfonate (1 m-PFOS) enantioseparation by SFC was established. The optimal separation was obtained using a Chiralpak QN-AX column with CO2 /2-propanol (70/30, v/v) as the mobile phase with a flow rate of 1 mL/min, column temperature was 32°C, and BPR pressure was 1800 psi. The resolution (Rs) and retention time were 0.88 and 130 minutes, respectively. This method is more economic and greener than HPLC. Modifier pH and column temperature were determined to be significant factors of SFC chiral separation. Modifier pH is negatively correlated with the retention factors and Rs. Adsorption thermodynamics were used to explain the influence of temperature change, and it was concluded that the transfer of two enantiomers from the mobile phase to the stationary phase is enthalpy-driven. Enantioseparation of 1 m-PFOS by SFC follows the same rules of ion exchange as those for the chiral separation by HPLC.

16.
Sci Total Environ ; 694: 133631, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31400675

RESUMO

Ubiquitous contamination of the BTEXS (benzene, toluene, ethylbenzene, xylene, and styrene) group in soils is a significant concern for ecological safety. However, comprehensive spatio-vertical survey of the BTEXS group on a national scale is rare to date. Using a static headspace gas chromatography-mass spectrometry method (HS-GCMS), this study performed a quantitative analysis of BTEXS levels in soils from Chinese rural areas in 2013 and 2016. The median ∑BTEXS concentrations in surface soils in 2013 and 2016 were 37.5 and 34.4 ng g-1 dry weight, respectively. Toluene was the dominant pollutant, accounting for approximately 41.6% and 32.1% of the total levels. BTEXS contamination was higher in Shanxi province, Northeast China, and Yunnan-Guizhou Plateau compared to the other regions. Vertically, toluene, m,p'-xylene and o'-xylene concentrations were significantly higher in the top soil layer (0-15 cm) and decreased significantly with increasing soil depth (p < 0.05). Higher soil organic matter was significantly associated with higher BTEXS concentrations of sampling site. BTEXS was also enhanced at sites with higher elevations and lower temperature due to global distillation effects. The findings of this study could help decision-makers to protect against BTEXS contamination in rural areas. These findings provide a basis for further study of the mechanism of BTEXS migration and transport in large-scale environment. CAPSULE: Spatio-vertical distribution, influence factors, exposure risks of BTEXS in soils from Chinese agricultural region was studied.

17.
J Hazard Mater ; 380: 120867, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31330388

RESUMO

Transplacental exposure to per/polyfluoroalkyl substances (PFASs) may impact fetal growth, but published evidence are still sparse and not in agreement. Moreover, little is known on the occurrence of emerging chlorinated polyfluorinated ether sulfonates (Cl-PFESAs, 6:2 and 8:2) in maternal-neonatal population. This study investigated eleven PFASs by analyzing 98 cord samples from Hangzhou, China. All target compounds can be transported across placenta, with highest median concentrations of 4.07, 1.05 and 0.731 ng/mL for PFOS, PFOA, and 6:2 Cl-PFESA. Older ages and higher pre-pregnancy BMI were associated with higher cord PFASs concentration; being primiparous was also significantly associated. Notably, after adjusting for potential confounders, PFOS was negatively associated with birth weight (ß = -417.3 g, 95% CI: -742.1, -92.4, p = 0.011, per a log10 unit increase in exposure) and ponderal index (ß = -0.005 g/cm3, 95% CI: -0.008, -0.002, p = 0.000). PFOS and PFHxS were also indicated to be associated with small for gestational age birth (SGA) (p <  0.05). Although no evidence of association was observed between Cl-PFESAs and birth outcomes in this study, the bioaccumulative properties and development toxicity of Cl-PFESAs deserve continuous concern.

19.
Environ Sci Technol ; 53(15): 9252-9259, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31290320

RESUMO

Plant fatty acids have indispensable physiological functions and nutritional value. However, the overuse of herbicides may cause phytotoxic disturbances of fatty acids in nontarget plants while spraying for weeds. Evidence has shown that the herbicide dichlorprop can inhibit the activity of acetyl-CoA carboxylase (ACCase), a key enzyme involved in fatty acid synthesis. However, the enantioselective phytotoxic effects of dichlorprop enantiomers ((R)-dichlorprop and (S)-dichlorprop) on fatty acids and their related mechanisms remain unclear. To solve this issue, the enantioselective phytotoxicity of dichlorprop in the model plant species Arabidopsis thaliana (A. thaliana) with a focus on fatty acids was evaluated for the first time. The results indicated a significant difference in enantioselectivity and that exposure to (R)-dichlorprop can cause marked fatty acid disturbances in nontarget plant species. Specifically, (R)-dichlorprop decreased the content of three fatty acids by more than 50% by inhibiting the activity of ACCase. In addition, increased malondialdehyde (MDA) and lipid hydroperoxides (LOOHs) contents and membrane permeability reflected herbicide-induced lipid peroxidation, which decreased the unsaturation of fatty acids in membranes and further influenced membrane composition and function. Moreover, an increased level of glutathione peroxidase (GPX) and cytochrome P450 (CYP450) reflected a plant stress-induced response. To summarize, fatty acids represent a new perspective for evaluating the toxicity of chiral pesticides, contributing to a better understanding of the enantioselective phytotoxicity and mechanisms of dichlorprop, and providing evidence for herbicide security and risk assessments.

20.
Artigo em Inglês | MEDLINE | ID: mdl-31313887

RESUMO

BACKGROUND: Extranodal natural killer (NK)/T-cell lymphoma, nasal type (ENKTL-N) is an aggressive lymphoma typically diagnosed by examining small biopsy specimens. Flow cytometry is very valuable for the diagnosis and classification of several kinds of hematolymphoid neoplasms but has not been widely used for diagnosing ENKTL-N. METHODS: We systematically investigated the flow cytometry characteristics of 26 solid tissue biopsy specimens of ENKTL-N at initial diagnosis and compared the results with those from reactive NK-cells in the nasal/nasopharyngeal region and peripheral blood. RESULTS: Our study revealed seven flow cytometry (FCM)-based characteristics for distinguishing between the neoplastic cells and reactive NK-cells, including (1) the proportion of NK-cells among total lymphocytes >10%; (2) forward scatter >105 ; (3) mean fluorescence intensity of CD56 > 5,000; (4) aberrant antigen expression or loss; (5) skewed killer cell immunoglobulin-like receptor repertoire; (6) homogenously positive for CD38; and (7) positive for CD30 or CD336. FCM-based immunophenotyping is a potentially feasible and convenient approach for discriminating cellular lineages, evaluating the activation status of NK-cells, and selecting potential therapy targets of ENKTL-N. CONCLUSIONS: Flow cytometry is very valuable for facilitating routine diagnosis, confirming clonality, predicting the cellular lineage, and guiding individual treatment for ENKTL-N. © 2019 International Clinical Cytometry Society.

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