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1.
Biochim Biophys Acta Biomembr ; : 183244, 2020 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-32126235
2.
J Cell Mol Med ; 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32175662

RESUMO

Intracoronary application of nicorandil can effectively reduce the myocardial no-reflow (MNR) after percutaneous coronary intervention (PCI). We sought to investigate the mechanisms of nicorandil in preventing MNR, besides that of dilating the coronary microvasculature. A total of 60 patients undergoing PCI were enrolled and randomly divided into a nicorandil group and a control group. Before PCI, 2 mg of nicorandil or an equal volume of normal saline was injected into the coronary artery. Blood samples were collected before, 24 hours and 1 week after PCI and inflammatory cytokines were tested. In the control group, the expression of pro-inflammatory cytokines was significantly increased, while the anti-inflammatory cytokines were decreased 24 hours after PCI. In contrast, these changes were reversed in the nicorandil group, indicating that nicorandil regulated the inflammatory response induced by PCI. Then, proteomic analysis was performed to further elucidate the potential mechanisms. A total of 53 differentially expressed proteins (DEPs) were found 24 hours after PCI in the control group, and the changes of these relevant genes were reversed in the nicorandil group. These DEPs were significantly enriched in the inflammatory pathways. In conclusion, the intracoronary application of nicorandil before PCI can regulate the inflammatory responses induced by PCI, which might be an important mechanism of nicorandil in preventing MNR.

3.
J Exp Clin Cancer Res ; 39(1): 31, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32028978

RESUMO

BACKGROUND: Recurrence and distant metastasis are still the main factors leading to treatment failure for malignant tumors including nasopharyngeal carcinoma (NPC). Therefore, elucidating the molecular mechanisms underlying nasopharyngeal carcinoma metastasis is of great clinical significance for targeted gene therapy and prognostic evaluation. PinX1, a tumor suppressor gene, was previously demonstrated to be a powerful tool for targeting telomerase in order to resist malignant tumor proliferation and migration. The aim of this study was to explore the mechanism through which PinX1 regulates epithelial-mesenchymal transition (EMT) and tumor metastasis in NPC and investigate its clinical significance and biological role with respect to disease progression. METHODS: Cell Counting Kit-8 (CCK8), Transwell assays, Colony formation analysis and Xenograft tumorigenicity assay were used to measure the nasopharyngeal CD133+ cancer stem cell proliferation, migration, and invasion abilities. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blot assays were conducted to investigate the underlying mechanism that PinX1 inhibits cell proliferation, migration, and invasion via regulating EMT in nasopharyngeal CD133+ CSCs. RESULTS: We found that the overexpression of PinX1 and P53 inhibited cell proliferation, migration, and invasion, but that the inhibition of miR-200b blocked these effects, in nasopharyngeal CD133+ cancer stem cells (CSCs). Mechanistic investigations elucidated that PinX1 inhibits cell proliferation, migration, and invasion by regulating the P53/miR-200b-mediated transcriptional suppression of Snail1, Twist1, and Zeb1, consequently inhibiting EMT in nasopharyngeal CD133+ CSCs. CONCLUSIONS: Our findings indicate that PinX1 inhibits cell proliferation, migration, and invasion via P53/miR-200b-regulated EMT in the malignant progression of human NPC, which might suggest novel clinical implications for disease treatment.

4.
Acad Radiol ; 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31954606

RESUMO

RATIONALE AND OBJECTIVES: To prospectively compare the image quality (IQ) and lesion detection performance of reduced field-of-view (rFOV) and full FOV (fFOV) diffusion-weighted imaging (DWI) sequences in detecting insulinomas. MATERIALS AND METHODS: From October 2017 to September 2018, 67 patients with suspected insulinomas were prospectively enrolled and underwent imaging with both types of DWI sequences. The slice thickness (4 mm) and slice gaps (1 mm) were the same for the two DWI sequences, and the TR/TE was 2235/56 ms for the rFOV sequence and 1892/63 ms for the fFOV sequence. Three radiologists independently assessed the imaging quality (IQ) subjectively with a 5-point scale and objectively with signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) measurements. The IQ scores, CNR, SNR, lesion detection rates, and ADC values were compared. Receiver operating characteristic curves were generated, and the area under the curve (AUC) was used to compare the diagnostic performance. RESULTS: Fifty patients were tumor positive, with 65 tumors (size: 1.31 ± 0.77 cm, range: 0.6-5.8 cm). The IQ score, SNR, and CNR were significantly higher for rFOV DWI than for fFOV DWI (IQ: 3.64 ± 0.487 vs 3.310 ± 0.577, SNR: 22.520 ± 8.690 vs 10.284 ± 3.321, CNR: 3.454 ± 2.642 vs 1.327 ± 2.801, and all p < 0.05). For lesions less than 1.5 cm (n = 55), the lesion detection rates of the rFOV were statistically improved compared to those of the fFOV (90.7% vs. 75.9%, p = 0.039). The sensitivity of lesion detection was significantly improved with the rFOV-DWI sequences compared to that with the fFOV-DWI sequences (0.924 vs. 0.773, p = 0.013). The ADC values of the two DWI sequences were consistent for insulinomas and normal parenchyma. CONCLUSION: Considering the improvements in overall IQ and lesion detection and the consistency of ADC measurements, we suggest that rFOV DWI is a reliable auxiliary alternative to fFOV DWI for clinical practice in the detection of pancreatic insulinomas.

5.
Eur J Radiol ; 124: 108779, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31935594

RESUMO

PURPOSE: We sought to evaluate the image quality and compare the signal intensity (SI) and apparent diffusion coefficient (ADC) maps of ultra-high b-value (2000 s/mm2; B2) images against those of 800 s/mm2 b-value (B1) images of diffusion-weighted imaging (DWI) for cervical cancer. METHOD: This study was approved by the institutional review board. Sixty patients diagnosed with cervical cancer by pathology were prospectively included. Female pelvic magnetic resonance imaging was performed using a 3 T magnetic resonance scanner; B1 and B2 images were obtained for evaluation. Two radiologists blinded to the scan parameters evaluated the images for signal loss in the background, spatial distortion, image ghosting, confidence in the lesion delineation, and overall image quality using a 5-point scoring system. The scores were compared using a paired Wilcoxon test. SI was measured in the B1 and B2 images for the tumour and normal reference tissues. Additionally, the SI contrast ratios were calculated and compared using the Mann-Whitney U test, the ADC values of tumours and normal tissues were measured, and the maximum tumour diameters were measured from the B1 and B2 images and compared with those from the T2-weighted images, which was the reference standard. RESULTS: The signal loss in the background, confidence of the lesion delineation and overall image quality scores were higher for the B2 images than for the B1 images (all p < 0.001). The contrast ratios of the tumour-to-normal SI were also higher for the B2 images than for the B1 images (p < 0.01). The mean ADC values derived from the B2 images showed better correlations with the tumour differentiation grades than those from the B1 images. The tumour diameters measured from the B2 images experienced less bias than those from the B1 images. CONCLUSIONS: B2 images of DWI are technically feasible to acquire and provide more promising additional information for the delineation of cervical cancer tumours than B1 images of the female pelvis.

6.
J Magn Reson Imaging ; 51(3): 824-832, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31313426

RESUMO

CONTRACT GRANT SPONSOR: Chinese Academy of Medical Sciences (CAMS) Initiative for Innovative Medicine; Contract grant number: 2017-I2M-1-001; Contract grant sponsor: Outstanding Youth Fund of Peking Union Medical College Hospital; Contract grant number: JQ201704; Contract grant sponsor: National Natural Science Foundation of China; Contract grant number: 81871512; Contract grant sponsor: National Public Welfare Basic Scientific Research Program of Chinese Academy of Medical Sciences; Contract grant numbers: 2018PT32003 and 2017PT32004. BACKGROUND: Both compressed-sensing (CS) and gradient- and spin-echo (GRASE) sequences can achieve 3D magnetic resonance cholangiopancreatography (MRCP) with a single breath-hold (BH). This work hypothesized that compared with conventional navigator-triggered (NT)-MRCP, the two BH-MRCP protocols, GRASE and CS, may provide better imaging quality, especially for patients with irregular breathing. PURPOSE: To evaluate and compare the image quality and diagnostic performance of three MRCP protocols. STUDY TYPE: Prospective. SUBJECTS: Seventy-four patients suspected to have duct-related pathologies were enrolled. FIELD STRENGTH: 3.0T. SEQUENCES: NT-MRCP, BH-CS-MRCP, and BH-GRASE-MRCP. ASSESSMENT: Breath regularity was evaluated subjectively according to the respiratory waves. The acquisition time was compared. The pancreaticobiliary system was divided into 12 segments and evaluated on a 5-point scale. The diagnostic performance of the three MRCPs was evaluated and compared. STATISTICAL TESTS: The Friedman test with a post-hoc test, receiver operating characteristic (ROC) curve analysis, McNemar test, and Kendall's W test were used. RESULTS: The BH-MRCP decreased the scan time significantly (P < 0.05). The overall imaging scores of GRASE-MRCP and CS-MRCP were significantly higher than that of NT-MRCP for patients with irregular breathing (4.283 and 4.283 vs. 3.000, both P < 0.05). Compared with NT-MRCP, the diagnostic performance of BH-CS and BH-GRASE MRCP was significantly improved for patients with irregular breathing (AUC = 0.860 and 0.863 vs. 0.572, both P < 0.001). DATA CONCLUSION: Compared with conventional NT-MRCP, the overall imaging quality and diagnostic performance of BH-CS and BH-GRASE MRCP were not significantly different for patients with regular breathing and significantly superior for patients with irregular breathing. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2020;51:824-832.

7.
Angew Chem Int Ed Engl ; 59(11): 4401-4405, 2020 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-31849167

RESUMO

Commercial ultrafiltration membranes have proliferated globally for water treatment. However, their pore sizes are too large to sieve gases. Conjugated microporous polymers (CMPs) feature well-developed microporosity yet are difficult to be fabricated into membranes. Herein, we report a strategy to prepare molecular-sieving membranes by partitioning the mesoscopic channels in water ultrafiltration membrane (PSU) into ultra-micropores by space-confined polymerization of multi-functionalized rigid building units. Nine CMP@PSU membranes were obtained, and their separation performance for H2 /CO2 , H2 /N2 , and H2 /CH4 pairs surpass the Robeson upper bound and rival against the best of those reported membranes. Furthermore, highly crosslinked skeletons inside the channels result in the structural robustness and transfer into the excellent aging resistance of the CMP@PSU. This strategy may shed light on the design and fabrication of high-performance polymeric gas separation membranes.

8.
Huan Jing Ke Xue ; 40(8): 3397-3404, 2019 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854743

RESUMO

The Beijing-Tianjin-Hebei (BTH) region experienced a heavy pollution episode in December 2016. Beijing and Tianjin issued a red alert from 20:00 December 16 to 24:00 December 21, while every city in Hebei Province (except Zhangjiakou, Chengde, and Qinhuangdao) issued a red alert from 00:00 December 16 to 18:00 December 22. In order to study the process of heavy pollution and the effect of implementing emergency measures, pollutant concentrations, meteorological conditions, air mass transmission and region transmission, and control effects were analyzed based on environmental monitoring data and simulation. Mean PM2.5 concentrations during the heavy pollution episode in each city all exceeded 200 µg·m-3 and the peak value of hourly averaged concentration (834.5 µg·m-3) occurred in Handan. The meteorological conditions during the heavy pollution episode restricted the diffusion of pollutants, with low pressure and air mass transmission exacerbating the problem. The mean fraction of PM2.5 concentrations in local emissions was 47.1%, but this differed between cities due to variable meteorological conditions. The average reduction of PM2.5 concentrations was 27.6%, indicating that the implementation of a red alert measure was effective. If the emergency measures had been implemented a few days earlier, a greater reduction ratio would have been achieved; a 4.4% greater average reduction in PM2.5 concentrations would have occurred if the measures were implemented two days earlier, while taking action three or more days in advance would not have achieved significant improvement.

9.
Integr Zool ; 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31773900

RESUMO

One of the most striking radiations in brachyuran evolution is the considerable morphological diversification of the external reproductive structures of primary freshwater crabs: the male first gonopod (G1) and the female vulva (FV). However, the lack of quantitative studies, especially the lack of data on female genitalia, has seriously limited our understanding of genital evolution in these lineages. Here we examined 69 species of the large Chinese potamid freshwater crab genus Sinopotamon Bott, 1967 (more than 80% of the described species). We used a landmark-based geometric morphometric approach to analyze variation in the shape of the G1 and FV, and to compare the relative degree of variability of the genitalia with non-reproductive structures (the third maxillipeds). We found rapid divergent evolution of the genitalia among species of Sinopotamon when compared to non-reproductive traits. In addition, the reconstruction of ancestral groundplans, together with plotting analyses, indicated that the FV show the most rapid divergence, and that changes in FV traits correlate with changes in G1 traits. Here we provide new evidence for co-evolution between the male and female external genitalia of Sinopotamon that has likely contributed to rapid divergent evolution and an associated burst of speciation in this lineage. This article is protected by copyright. All rights reserved.

10.
Environ Sci Technol ; 53(24): 14752-14760, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31747513

RESUMO

The treatment of spent cooking liquor is critical for clean production of pulp and paper industry. There is a compelling need to develop a cost-effective and green technology for reuse of organic matter in spent cooking liquor to mitigate the negative impacts on the environment. The objective of this study is to examine the chemical structure of fulvic acid-like substances extracted from spent cooking liquor (PFA) and their relationship with bioactivity in plant growth. Compared with the benchmark Pahokee peat fulvic acid (PPFA), PFA has less aromatic structure, but higher content of lignin, carbohydrates, and amino acid. After fractionation, protein/amino proportion decreased with increasing molecular weight, but the aromaticity increased. Under salt stress, rice seedling growth was promoted by PFA with low molecular weight (<5 kDa), but inhibited by fraction with high molecular weight (>10 kDa). Principal component analysis suggested that promoted growth was more related with chemical structure (O- and N-alkyl moieties) than with molecular weight. This study provided the theoretical basis for development of an innovative green technology of sustainable reuse of spent cooking liquor in agriculture.

11.
J Cardiothorac Surg ; 14(1): 175, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31615578

RESUMO

BACKGROUND: Bilateral internal mammary artery (BIMA) grafting has a good long-term survival rate and graft patency rate, but it is only recommended in young patients due to its high technical requirements and high incidence of sternal complications. Previous studies indicated that BIMA grafting has a significant benefit in patients aged 50-59 years, but this benefit does not extend to patients aged > 60 years. Thus, this study was designed to analyse the immediate artery graft function, short-term (3 months) results, and experience in preventing sternal complications for BIMA grafting in elderly patients (60-75 years old). METHODS: Clinical records and echocardiographic and coronary artery computed tomography angiography data of 155 patients who underwent BIMA grafting for coronary artery disease between 2015 and 2017 in our hospital were analysed retrospectively to summarise the operative experience and short-term (3 months) results. Patients were divided into two groups: Group A (n = 95), aged < 60 years and Group B (n = 60), aged 60-75 years. The operation time, aortic clamp time, and cardiopulmonary bypass time of these two groups were compared to analyse the operation difficulty and the flow and pulsatility index were compared to analyse the immediate artery graft function. The left ventricular end-diastolic dimension (LVEDD) and left ventricular ejection fraction (LVEF) of these two groups were compared to analyse heart function. RESULTS: There were no significant differences in the operation time, aortic clamp time, and cardiopulmonary bypass time as well as the flow and pulsatility index between these two groups (P > 0.05). There was no significant difference in the incidence of sternal wound complications, graft occlusion, and other common complications 3 months post-BIMA grafting between these two groups (P > 0.05). Furthermore, there was no significant difference in LVEDD and LVEF between the groups 3 months post-operation (P > 0.05). CONCLUSIONS: BIMA grafting was safe and effective for older patients (60-75 years). Similar to younger patients (< 60 years), BIMA grafting in elderly patients (60-75 years) can also achieve a satisfactory short-term (3 months) result. Thus, advanced age (60-75 years) should not be a contraindication for BIMA grafting.


Assuntos
Ponte de Artéria Coronária/métodos , Doença da Artéria Coronariana/cirurgia , Artéria Torácica Interna/transplante , Fatores Etários , Idoso , Angiografia por Tomografia Computadorizada , Angiografia Coronária , Ecocardiografia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Estudos Retrospectivos , Volume Sistólico , Deiscência da Ferida Operatória/epidemiologia , Infecção da Ferida Cirúrgica/epidemiologia , Resultado do Tratamento , Função Ventricular Esquerda
12.
Comp Immunol Microbiol Infect Dis ; 67: 101346, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31550674

RESUMO

Cryptosporidium spp., Enterocytozoon bieneusi, and Giardia duodenalis are globally ubiquitous infectious parasitoses in humans and animals. The purpose of the present study was to determine the distribution and genetic diversity of Cryptosporidium spp., Enterocytozoon bieneusi, and Giardia duodenalis from animal sources in different regions of QTPA in China. A total of 405 fresh fecal specimens from seven domestic animals were collected in Qinghai, Yunnan, and Tibet. The overall prevalence of Cryptosporidium spp., E. bieneusi and G. duodenalis was 3.0% (n = 12), 19.8% (n = 80) and 5.7% (n = 23), respectively. Four Cryptosporidium species (C. andersoni, C. xiaoi, C. bovis, and C. ryanae) were identified and C. bovis was firstly identified from camel. Ten genotypes of E. bieneusi were identified in the present study, including eight known genotype (BEB6, CAM2, CHG2, CAM1, COS I, J, CHS8, and CHG3), and two novel genotypes (YAK1 and PN). Genotype CAM2 was detected in horse, yak, and mongolian sheep for the first time and the novel genotype YAK1 was grouped into the human-pathogenic group 1. G. duodenalis assemblage E was common in all animal species, and the human-pathogenic assemblage A was only detected in yaks and camels. Our results elucidate the occurrence and genetic diversity of three zoonotic pathogens from different animals and regions in QTPA, which could act as potential zoonotic reservoirs. More areas and larger number of samples are required to assess the potential risk of cross-species transmission in this region.

13.
Nat Commun ; 10(1): 4204, 2019 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-31527592

RESUMO

Metal-organic frameworks (MOFs) with high porosity and designable functionality make it possible to access the merits of high permeability and selectivity. However, scalable fabrication methods to produce mixed matrix membranes (MMMs) with good flexibility and ultrahigh MOF loading are urgently needed yet largely unmet. Herein, we report a thermally induced phase separation-hot pressing (TIPS-HoP) strategy to roll-to-roll produce 10 distinct MOF-membranes (loadings up to 86 wt%). Ultrahigh-molecular-weight polyethylene interweaving the MOF particles contributes to their mechanical strength. Rejections (99%) of organic dyes with a water flux of 125.7 L m-2 h-1 bar-1 under cross-flow filtration mode. The micron-sized channels between the MOF particles translate into fast water permeation, while the porous MOFs reject solutes through rapid adsorption. This strategy paves ways for developing high-performance membrane adsorbers for crucial separation processes. As a proof-of-concept, the abilities of the membrane adsorbers for separating racemates and proteins have been demonstrated.


Assuntos
Estruturas Metalorgânicas/química , Adsorção , Membranas Artificiais , Porosidade , Proteínas/isolamento & purificação , Propriedades de Superfície
14.
JCI Insight ; 4(16)2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31434801

RESUMO

BACKGROUNDCytokine biomarkers have already been used to predict acute graft-versus-host disease (aGVHD) onset, nonrelapse mortality, and overall survival in human and mouse models, but the consistency of the consequences between patients and mice has not been evaluated. Furthermore, no study about any biomarker or biomarker panel for aGVHD grading or steroid sensitivity of aGVHD patients simultaneously has been reported.METHODSHere we established an aGVHD mouse model and explored the relation between aGVHD onset and variations of some cytokines. Based on the results and latest progress, we selected 16 cytokines and compared their serum variations in aGVHD patients and non-aGVHD patients after allogeneic hematopoietic stem cell transplantation. Using protein microarray, we explored the relation between the cytokine levels and aGVHD-related events (onset, grading, and steroid sensitivity).RESULTSThe increase of chemokine levels in murine aGVHD was very consistent with that of patients. We found obviously higher levels of IL-2, IL-4, Elafin, sST2, TLR4, and TNF-α, and lower levels of TGF-ß in both aGVHD mouse models and aGVHD patients. In addition, patients with severe aGVHD showed increased IL-6, TLR4, TNF receptor 1 (TNFR1), and Elafin and decreased TGF-ß. TLR4 and TNFR1 were significantly increased in steroid-refractory aGVHD patients compared with steroid-effective patients (P < 0.05).CONCLUSIONA combination of TLR4, TNFR1, TGF-ß, and Elafin could be a new 4-biomarker panel to assist aGVHD diagnosis, grading, and evaluation of steroid sensitivity for clinical aGVHD patients.TRIAL REGISTRATIONChiCTR1900022292 "Clinical Research of Umbilical Cord-Derived Mesenchymal Stromal Cells in the Prophylaxis of Graft-Versus-Host Disease After HLA-Haploidentical Stem-Cell Transplantation."FUNDINGNational Key Research Program, National Natural Science Foundation of China, Chongqing Social Career and People's Livelihood Security Science and Technology Innovation Project, Fundamental and Frontier Research Program of Chongqing, and Foundation of Xinqiao Hospital.

15.
Magn Reson Imaging ; 63: 105-113, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31425797

RESUMO

PURPOSE: This study aimed to investigate whether amide proton transfer (APT) imaging, compared with intravoxel incoherent motion (IVIM) imaging-derived parameters, can differentiate squamous cell carcinoma of the cervix (SCCC) from the normal cervical stroma and distinguish poorly differentiated SCCC from well-moderately differentiated SCCC. METHODS: This prospective study enrolled 32 patients, comprising 20 patients with well-moderately differentiated SCCC and 12 patients with poorly differentiated SCCC. 20 healthy volunteers were enrolled as a control group. A bi-exponential model (BEM) analysis was performed to derive ADC, pure molecular diffusion coefficient (D), pseudo-diffusion coefficient (D*) and perfusion fraction (f). The APT signal intensity (APT SI), ADC, D, D* and f were measured. The parameters between the groups were compared with independent t-tests. Diagnostic performance was evaluated with a ROC analysis. RESULTS: The APT SI of SCCC (2.92 ±â€¯0.24%) was higher than that of normal cervical stroma (2.72 ±â€¯0.36%) with P = 0.020. The comparison of the AUCs for the diagnosis of SCCC was ADC > f > APT SI > D* > D. A significant difference was found in the APT SI between the well-moderately differentiated SCCC group (2.82 ±â€¯0.15%) and the poorly differentiated SCCC group (3.09 ±â€¯0.27%) with P = 0.006. Except for D (P = 0.012), the ADC, D* and f values were not significantly different between the groups (P > 0.05). The comparison of the AUCs for distinguishing poorly differentiated SCCC was APT SI > D > ADC > D* = f. CONCLUSION: APT imaging may be a useful technique in the diagnosis and predicting the differentiation of SCCC.

16.
Plant Signal Behav ; 14(10): e1649568, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31397633

RESUMO

High light and high temperature (HLHT) stress induces the production of damaging reactive oxygen species (ROS) in many plants. Recently, we described a HLHT-sensitive rice (Oryza sativa) mutant, local lesions (ls1), that exhibits local lesions under HLHT, due to DNA damage and excess ROS accumulation. Here, we determined that an HLHT treatment induced the local lesion phenotype in ls1 within 6 h. Corroborating this result, we found that transient HLHT treatment influenced the expression of many genes in the ls1 mutant, while affecting the growth and development of young leaves.

17.
Magn Reson Imaging ; 63: 21-28, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31319128

RESUMO

PURPOSE: To explore changes in the amide proton transfer (APT) signal intensity (SI) among different phases of the menstrual cycle in healthy young women and to determine whether the APT SI correlates with the apparent diffusion coefficient (ADC). MATERIALS AND METHODS: Twenty healthy women of childbearing age received regular pelvic magnetic resonance imaging (MRI) examinations and APT scans during the menstrual, proliferative and secretory phases of their menstrual cycle. Then, the APT SI and ADC values of the endometrium, myometrium and junctional zone were measured and analyzed to explore the changes during different phases of the menstrual cycle. The Pearson correlation coefficients between the APT SI and ADC were calculated. RESULTS: Besides the APT SI in the secretory phase, the APT SI and ADC in each menstrual phase were higher in the myometrium and endometrium than in the junctional zone, the APT Si did not differ significantly between the endometrium and myometrium during any phase. In each uterine structure, both the SI and ADC were highest in the secretory phase, second highest in the proliferative phase and lowest in the menstrual phase, but the APT SI did not differ significantly between the menstrual phase proliferative phases. Interindividual variation in APT SI and ADC for a given zone or phase ranged from 1.86% to 2.75% and from 0.37 × 10-3 mm2/s to 0.85 × 10-3 mm2/s, respectively. The Pearson correlation coefficient between APT SI and ADC was 0.481 (P < 0.01). CONCLUSION: When the APT SI or ADC values are used to analyze uterine lesions, their changes during the menstrual cycle in childbearing aged women should be considered.

18.
ACS Nano ; 13(8): 8577-8588, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31339295

RESUMO

Ischemic stroke caused by a thrombus clog and ischemia is one of the most lethal and disabling cerebrovascular diseases. A sequentially targeted delivery system is highly desired to deliver thrombolytics and neuroprotectant to the site of the thrombus and ischemic penumbra, respectively, to pursue a maximized combinational effect. Inspired by the vital roles that platelets play in thrombus formation, herein, we develop a bioengineered "nanoplatelet" (tP-NP-rtPA/ZL006e) for sequentially site-specific delivery of recombinant tissue plasminogen activator (rtPA) and neuroprotectant (ZL006e) for ischemic stroke treatment. The tP-NP-rtPA/ZL006e consists of a ZL006e-loaded dextran derivative polymeric nanoparticle core and platelet membrane shell conjugated with thrombin-cleavable Tat-peptide-coupled rtPA. Mediated by the cloak of the platelet membrane, tP-NP-rtPA/ZL006e targets the thrombus site and rtPA is triggered to release by the upregulated thrombin. Subsequently, the in situ exposed Tat peptide enhanced penetration of the "nanoplatelet" across the blood-brain barrier into ischemic brain for ZL006e site-specific delivery. From the in vitro and in vivo evaluation, tP-NP-rtPA/ZL006e is demonstrated to significantly enhance the anti-ischemic stroke efficacy in the rat model  with middle cerebral artery occlusion, showing a 63 and 72% decrease in ischemic area and reactive oxygen species level compared to that with free drug combination, respectively.

19.
Anal Bioanal Chem ; 411(21): 5383-5391, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31179527

RESUMO

Rapid, portable, and efficient detection of lead cations (Pb2+) is of great significance for monitoring and evaluating environmental toxicity and human healthcare. In this work, we developed a simple and low-cost homogenous fluorescence DNAzyme assay for Pb2+ determination based on Pb2+-dependent cleaving and rolling circle amplification (RCA). DNAzyme and its substrate (5'-biotin) formed double-stranded hybrids in solution which could thoroughly react with Pb2+ in aqueous phase. Then, the unreacted DNAzyme/substrate hybrids as well as cleaved parts with biotin labeling of substrate strand would be captured by magnetic beads through biotin-streptavidin interactions and removed from the reaction solution. Meanwhile, the other parts of the substrate strand remained in solution and subsequently acted as the primer and triggered RCA. The concentration of the cleaved substrate strand correlated to that of Pb2+ and non-specific amplification was effectively minimized through biotin-streptavidin isolation. With a smartphone camera, the fluorescence intensity was recorded and quantified after 30-90 min amplification, making it a portable method with minimum instrumentation. A dynamic range of 1-100 nM of Pb2+ was achieved under optimized conditions and it was successfully employed for Pb2+ detection in spiked lake water. Graphical abstract.


Assuntos
Técnicas Biossensoriais/métodos , DNA Catalítico/química , Chumbo/análise , Smartphone , Artefatos , Biotina/química , Cátions , Fluorescência , Corantes Fluorescentes/química , Limite de Detecção , Estudo de Prova de Conceito , Estreptavidina/química
20.
J Hazard Mater ; 378: 120702, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31202064

RESUMO

Increasing environmental concerns about organic waste in paper mill effluents demand alternative wastewater management technology. We reported novel activation of fulvic acid-like in paper mill effluents using hydrogen peroxide (H2O2) as oxidizer and titanium oxide (TiO2) as catalyst. Spectroscopic characteristics of fulvic acid-like in paper mill effluents before and after activation (PFA and PFA-Os, respectively) were compared with a benchmark fulvic acid extracted from leonardite (LFA). Results indicated that PFA-Os exhibited less lignin structures, more functional groups and lower molecular weight than PFA, sharing much similarity with LFA. Among PFA-Os with varying degrees of oxidation, PFA-O-3 activated with 1:2 vol ratio of paper mill effluent and 30% H2O2 for 20 min digestion at 90 °C stands out to be the optimal for further examination of its biological activity. Bioassays with rice seed/seedling indicated that applications of LFA at 2-5 mg-C/L and PFA-O-3 at 60-100 mg-C/L significantly increased rice seed germination rate and seedling growth under salt stress imposed with 100 mM NaCl. The mechanism was mainly through reduced oxidative damage via activation of antioxidative enzymes and lipid peroxidation. This study provides the needed technical basis of safer and cleaner technologies for innovative management of paper mill effluents.

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