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1.
Toxicol In Vitro ; : 105091, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-33440188

RESUMO

Ketamine is widely used in pediatric anesthesia, perioperative sedation, and analgesia. Knowledge of anesthesia neurotoxicity in humans is currently limited by the difficulty of obtaining neurons and performing developmental toxicity studies in fetal and pediatric populations. However, mouse embryonic stem cells (mESCs) derived from embryos at the preimplantation stage demonstrate an unlimited ability to self-renew and generate different cell types and are a valuable tool for clinical research. Thus, in this study, a model was employed to investigate the mechanism by which ketamine (200 nM) influences the neuronal differentiation of mESCs. Mouse ESCs were treated with an anesthetic dose of ketamine, and neuronal differentiation was significantly inhibited on day 5. Downregulation of brain-derived neurotrophic factor (BDNF) by shRNA was found to have the same inhibitory effect. Furthermore, a rescue experiment indicated that BDNF overexpression markedly restored the neuronal differentiation inhibited by ketamine in the ketamine/BDNF group on day 5. Taken together, these data suggested that ketamine inhibited the neuronal differentiation of mESCs, possibly by interfering with BDNF. The results of the current study may provide novel ideas for preventing ketamine toxicity in the developing fetus.

2.
World Neurosurg ; 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33412325

RESUMO

OBJECTIVE: The aim of the present study was to investigate the clinical characteristics and factors affecting the prognosis of myxopapillary ependymoma(MPE) METHODS: We retrospectively analyzed the clinical data of 24 patients diagnosed with MPE who were surgically treated from January 2010 to January 2020 in the Department of Neurosurgery at Tongji Hospital (Tongji Medical School, Huazhong University of Science and Technology) RESULTS: Among the 24 included patients, there were 13 males and 11 females. The ages of the included patients ranged from 15 to 59 year-old, with an average age of 35.2 year-old. The Preoperative McCormick grade included 20 cases (83.3%) in grade II, 4 cases (16.7%) in grade III. The follow-up times ranged from 6 months to 10 years, with an average of 50.9 months. The Postoperative McCormick grade included 7 cases (29.2%) in grade I, 4 cases (16.7%) in grade II, 12 cases (50%) in grade III and 1 case (4.2%) in grade IV. The 1-year, 2-year and 10-year recurrence rate was 8.3%, 29.2%, 41.7% respectively. The 1-year, 2-year and 10-year survival rate was 100%, 100%, 95.8% respectively. Chi-square test revealed a significant difference between the degree of surgical resection (P=0.012<0.05). The Kaplan-Meier method found that the degree of tumor resection (P=0.031<0.05) was related to progression free survival (PFS). The COX analysis revealed there was no significant independent prognostic factors. CONCLUSION: Our findings suggest that the degree of surgical resection was a key factor that affected the prognosis and neurological function of the included MPE patients.

3.
Autophagy ; : 1-23, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33455530

RESUMO

Intervertebral disc degeneration (IDD) is the primary pathological mechanism that underlies low back pain. Overloading-induced cell death, especially endogenous stem cell death, is the leading factor that undermines intrinsic repair and aggravates IDD. Previous research has separately studied the effect of oxygen concentration and mechanical loading in IDD. However, how these two factors synergistically influence endogenous repair remains unclear. Therefore, we established in vitro and in vivo models to study the mechanisms by which hypoxia interacted with overloading-induced cell death of the nucleus pulposus derived stem cells (NPSCs). We found the content of HIF1A (hypoxia inducible factor 1 subunit alpha) and the number of NPSCs decreased with disc degeneration in both rats and human discs. Hence, we isolated this subpopulation from rat discs and treated them simultaneously with hypoxia and excessive mechanical stress. Our results demonstrated that hypoxia exerted protective effect on NPSCs under compression, partially through elevating macroautophagy/autophagy. Proteomics and knockdown experiments further revealed HIF1A-BNIP3-ATG7 axis mediated the increase in autophagy flux, in which HMOX1 and SLC2A1 were also involved. Moreover, HIF1A-overexpressing NPSCs exhibited stronger resistance to over-loading induced apoptosis in vitro. They also showed higher survival rates, along with elevated autophagy after being intra-disc transplanted into over-loaded discs. Jointly, both in vivo and in vitro experiments proved the anti-apoptotic effect of HIF1A on NPSCs under the excessive mechanical loading, suggesting that restoring hypoxia and manipulating autophagy is crucial to maintain the intrinsic repair and to retard disc degeneration. Abbreviations: 3-MA: 3-methyladenine; ACAN: aggrecan; ATG7: autophagy related 7; BafA1: bafilomycin A1; BAX: BCL2 associated X, apoptosis regulator; BECN1: beclin 1; BNIP3: BCL2 interacting protein 3; BNIP3L: BCL2 interacting protein 3 like; CASP3: caspase 3; CCK8: cell counting kit-8; CHT: chetomin; CMP: compression; CoCl2: cobalt chloride; COL2A1: collagen type II alpha 1 chain; Ctrl: control; DAPI: 4,6-diamidino-2-phenylindole; DEP: differentially expressed protein; DiR: 1,1-dioctadecyl-3,3,3,3-tetramethyl indotricarbocyanine; ECM: extracellular matrix; FCM: flow cytometry; GD2: disialoganglioside GD 2; GFP: green fluorescent protein; GO: gene ontology; GSEA: gene set enrichment analysis; H&E: hematoxylin-eosin; HIF1A: hypoxia inducible factor 1 subunit alpha; HK2: hexokinase 2; HMOX1: heme oxygenase 1; HX: hypoxia mimicry; IDD: intervertebral disc degeneration; IF: immunofluorescence; IHC: immunohistochemistry; IVD: intervertebral disc; KEGG: kyoto encyclopedia of genes and genomes; LBP: low back pain; Lv: lentivirus; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; MMP: mitochondrial membrane potential; NC: negative control; NIR: near-infrared; NP: nucleus pulposus; NPC: nucleus pulposus cell; NPSC: nucleus pulposus derived stem cell; NX: normoxia; PPI: protein-protein interactions; RFP: red fluorescent protein; SLC2A1/GLUT1: solute carrier family 2 member 1; SQSTM1/p62: sequestosome 1; TEK/TIE2: TEK receptor tyrosine kinase; TEM: transmission electron microscopy; TUBB: tubulin beta class I.

4.
Acta Ophthalmol ; 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33438364

RESUMO

PURPOSE: To evaluate the efficacy and safety of different agents, dosages and strategies of anti-vascular endothelial growth factor (VEGF) treatment for neovascular age-related macular degeneration (nAMD) by network meta-analysis. METHODS: Electronic database searches were conducted on PubMed, Embase and Cochrane Central Register of Controlled Trials up to 1 December 2019 to `identify relevant randomized controlled trials (RCTs). The standardized mean difference (SMD), odds ratios (OR), 95% confidence intervals (CI), the surface under the cumulative ranking curves and the mean ranks of each outcome were estimated by Stata 14.0. RESULTS: Forty-seven RCTs encompassing 17 872 nAMD patients randomly assigned to 36 regimens of anti-VEGF agents or sham treatment were included. T&E strategy shows top-level effect both in BCVA changes and the percentage of patients with a gain of 3 lines or more of BCVA. When taking the same strategy, there is no significant difference of efficacy among ranibizumab, bevacizumab and aflibercept (p > 0.05); The combination of radiation, topical NSAIDs and photodynamic therapy (PDT) might provide additional benefit in central retinal thickness (CRT) reduction; all these therapeutic regimens of different anti-VEGF agents do not significantly increase the risk of severe ocular or cardiocerebral vascular adverse events (ADEs) compared with sham treatment (p > 0.05). CONCLUSIONS: T&E strategy showed a satisfactory effect in visual improvement and there is no significant difference in efficacy or safety among ranibizumab, bevacizumab and aflibercept. All the included regimens have an acceptable risk of ADEs.

5.
Nucleic Acids Res ; 49(D1): D706-D714, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33045727

RESUMO

The COVID-19 outbreak has become a global emergency since December 2019. Analysis of SARS-CoV-2 sequences can uncover single nucleotide variants (SNVs) and corresponding evolution patterns. The Global Evaluation of SARS-CoV-2/hCoV-19 Sequences (GESS, https://wan-bioinfo.shinyapps.io/GESS/) is a resource to provide comprehensive analysis results based on tens of thousands of high-coverage and high-quality SARS-CoV-2 complete genomes. The database allows user to browse, search and download SNVs at any individual or multiple SARS-CoV-2 genomic positions, or within a chosen genomic region or protein, or in certain country/area of interest. GESS reveals geographical distributions of SNVs around the world and across the states of USA, while exhibiting time-dependent patterns for SNV occurrences which reflect development of SARS-CoV-2 genomes. For each month, the top 100 SNVs that were firstly identified world-widely can be retrieved. GESS also explores SNVs occurring simultaneously with specific SNVs of user's interests. Furthermore, the database can be of great help to calibrate mutation rates and identify conserved genome regions. Taken together, GESS is a powerful resource and tool to monitor SARS-CoV-2 migration and evolution according to featured genomic variations. It provides potential directive information for prevalence prediction, related public health policy making, and vaccine designs.

6.
Gen Thorac Cardiovasc Surg ; 69(1): 32-37, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32654090

RESUMO

OBJECTIVE: We evaluate the long-term clinical and echocardiographic outcomes of edge-to-edge (E2E) repair combined with mitral annuloplasty in our institute with degenerative mitral regurgitation (MR) up to 10 years. METHODS: Twenty-six consecutive patients undergoing E2E mitral repair after failure of other conventional mitral repair technique. There were 16 (61.5%) male and the mean age was 52.2 ± 10.4 years. Mitral regurgitation was due to anterior leaflet prolapse in 12 (46.2%) patients, bileaflet prolapse in 9 (34.6%), and multiple segment posterior leaflet prolapse in 5 (19.2%). RESULTS: There were no perioperative deaths. Follow-up was 100% complete. The mean length of follow-up was 8.7 ± 0.9 years (median 8.4 years, 6.8-10.1 years). Two patients required reoperation of the MV. The freedom from reoperation and ≥ Moderate MR at 10 years was 69.9 ± 11.7%. The freedom from reoperation, ≥ Moderate MR and mitral stenosis (MS) at 10 years was (59.6 ± 10.0) %. The mean transmitral pressure gradient (TMPG) was 6.1 ± 2.5 mmHg, which was significantly elevated compared with preoperative TTE (P = 0.004). The freedom from ≥ Moderate MS at 10 years was 76.9 ± 8.3%. There were no differences between patients with and without MS at follow-up regarding the echocardiographic parameters and clinical status. CONCLUSION: There is a slowly progressive elevation of TMPG after E2E mitral repair, while mildly elevated TMPG can be tolerated in most patients. In appropriate patients, the E2E repair combined with annuloplasty provides an effective "bailout" choice.

8.
Life Sci ; 265: 118795, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33227274

RESUMO

Conbercept is a newly-developed anti-vascular endothelial growth factor (VEGF) drug. This study aimed to evaluate the effects of conbercept on inflammation and oxidative response in proliferative diabetic retinopathy (PDR). Morphology changes in retinal microvasculature of PDR patients were determined by optical coherence tomographic angiography (OCTA). The mice were injected with streptozocin (STZ) for 20 weeks to induced PDR, then the changes in inflammatory factors, oxidative response and histological analysis were examined with Elisa assay, real time-PCR and commercial kits analysis. Conbercept treatment significantly alleviated the retinal pathological changes and significantly reduced intercellular cell adhesion molecule-1 (ICAM-1), macrophage inflammatory protein-1 (MIP-1), IL-1ß, IL-6 and TNF-α protein levels but not prostaglandin E1 (PGE1), prostaglandin E2 (PGE2) and prostaglandin F2a (PGF2a) levels, all of which were remarkably elevated in aqueous fluid of PDR patients compared with non-PDR subjects. Meanwhile the inhibitory effects of conbercept on these inflammatory factors were proved by RT-PCR assays in mice experiments. And the inflammatory signal such as p-IKBα and p-p65 was correspondingly inhibited by conbercept in STZ-treated mice. Conbercept treatment significantly elevated the aqueous glutathione level of PDR patients and inhibited NOX-1, NOX-4 and ph22phox mRNA expressions and ROS production of PDR mice. Ki67 immunofluorescence staining showed that conbercept inhibited endothelial cell proliferation in retina of PDR mice. In conclusion, conbercept significantly inhibited the angiogenesis, inflammation and oxidative response in PDR mice, and these findings further reveals the molecular mechanisms of conbercept in treating PDR.


Assuntos
Retinopatia Diabética/tratamento farmacológico , Mediadores da Inflamação/antagonistas & inibidores , Injeções Intravítreas/métodos , Estresse Oxidativo/efeitos dos fármacos , Proteínas Recombinantes de Fusão/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Animais , Retinopatia Diabética/metabolismo , Retinopatia Diabética/patologia , Feminino , Humanos , Mediadores da Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Estresse Oxidativo/fisiologia , Resultado do Tratamento
10.
Clin Rheumatol ; 40(1): 167-179, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32557257

RESUMO

OBJECTIVES: To explore the associations of FKBP4 and FKBP5 gene polymorphisms with disease susceptibility, glucocorticoid (GC) efficacy, anxiety, depression, and health-related quality of life (HRQOL) in systemic lupus erythematosus (SLE) patients. METHODS: All subjects were collected from the First and the Second Affiliated Hospital of Anhui Medical University in Hefei, China, during 2011 to 2015. In the case-control study, 541 SLE patients and 543 controls were recruited. In the follow-up study, 466 patients completed the 12-week follow-up and then were divided into GC-sensitive and GC-insensitive groups. Genotyping was determined using Multiplex SNaPshot technique. Data were analyzed using chi-square test and univariate and multivariate logistic regression analyses. RESULTS: rs4713904, rs9368878, and rs7757037 of FKBP5 were associated with depression in SLE patients (rs4713904, PBH = 0.037; rs9368878, PBH = 0.001; rs7757037, PBH = 0.003). Moreover, rs4713904 was associated with GC efficacy in males with SLE (PBH = 0.011). The rs755658 of FKBP5 was associated with improvement in social function (PBH = 0.022) and mental component summary (PBH = 0.028). The rs4713907 of FKBP5 was related to improvement in total score of SF-36, bodily pain, and mental component summary score (all PBH = 0.018). Furthermore, the rs12582595 of FKBP4 was correlated with general health improvement (PBH = 0.033). No associations were seen between FKBP4/FKBP5 gene polymorphisms and SLE susceptibility and anxiety. CONCLUSIONS: FKBP5 gene polymorphisms may be associated with depression and GC efficacy of SLE patients. Meanwhile, the genetic polymorphisms of FKBP4 and FKBP5 genes may be associated with HRQOL improvement in SLE patients. Key Points • FKBP5 gene polymorphisms were associated with depression of SLE patients. • FKBP5 gene polymorphisms were associated with GC efficacy of SLE patients. • FKBP5 gene polymorphisms were associated with HRQOL improvement in SLE patients. • FKBP4 gene polymorphisms were associated with HRQOL improvement in SLE patients.

11.
J Environ Radioact ; 227: 106507, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33321301

RESUMO

Inspired by microbial diagenesis and mounding, microbial mineralization technology has been widely used in the treatment of heavy metal and radionuclide contamination. S. pasteurii can decompose urea as a source of energy to produce CO32- in the microbial mineralization system. Therefore, strontium-contaminated radioactive wastewater can be effectively treated by combining CO32- with surrounding strontium ions (Sr2+) to form strontium carbonate (SrCO3). Herein, we investigated how the concentration of graphene oxide (GO) and mineralization time influence the morphology of SrCO3 and the mineralization efficiency. GO was used as a crystal regulator to solidify the radionuclide strontium in the microbial mineralization system to obtain large-scale rock-like SrCO3 minerals. The results showed that GO can adsorb the surrounding Sr2+ with oxygen-containing functional groups on its surface to form SrCO3 complexes, directly influencing the morphology and consolidation percentage of SrCO3. Considering the leaching behaviour of nuclides, we further studied the stability of consolidated SrCO3 minerals. The results indicated that the presence of GO improved the stability of the mineralized samples obtained in the microbial mineralization system.

12.
Spectrochim Acta A Mol Biomol Spectrosc ; 245: 118879, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32920440

RESUMO

A novel curcumin-analogous fluorescent sensor, DNP, was developed for cysteine detection with a bilateral-response click-like mechanism. DNP indicated high selectivity and practical sensitivity. It could recognize Cys from other biologically relevant molecules, especially, from GSH and Hcy. The most interesting point was that, with typical azide groups for sensing, DNP indicated a covalent binding procedure with Cys instead of a presupposed simple reduction for reductive sulfide. Moreover, the recognition occurred at both sides of the sensor. DNP could be utilized into the detection of endogenous and exogenous Cys in living cells. Though the specific optical performances of DNP still need optimization, this work supplied novel information for broadening the vision on fluorophores and mechanisms, for the monitoring of Cys and even other sulfur-containing species.

13.
World J Clin Cases ; 8(21): 5104-5115, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33269247

RESUMO

BACKGROUND: The current standard surgical treatment for non-metastatic upper urinary tract urothelial carcinoma (UTUC) is radical nephroureterectomy (RNU) with bladder cuff excision (BCE). Typically, BCE techniques are classified in one of the following three categories: An open technique described as intrasvesical incision of the bladder cuff, a transurethral incision of the bladder cuff (TUBC), and an extravesical incision of the bladder cuff (EVBC) method. Even though each of these management techniques are widely used, there is no consensus about which surgical intervention is superior, with the best oncologic outcomes. AIM: To investigate the oncological outcomes of three BCE methods during RNU for primary UTUC patients. METHODS: We retrospectively analyzed the data of 248 primary UTUC patients, who underwent RNU with BCE between January 2004 to December 2018. Patients were analyzed according to each BCE method. Data extracted included patient demographics, perioperative parameters, and oncological outcomes. Statistical analyses were performed using chi-square and log-rank tests. The Cox proportional hazards regression model was utilized to identify independent predictors. P < 0.05 was considered statistically significant. RESULTS: Of the 248 participants, 39.9% (n = 99) underwent intrasvesical incision of the bladder cuff, 38.7% (n = 96) EVBC, and 21.4% (n = 53) TUBC. At a median follow-up of 44.2 mo, bladder recurrence developed in 17.2%, 12.5%, and 13.2% of the cases, respectively. Cancer-specific deaths occurred in 11.1%, 5.2%, and 7.5% of patients, respectively. Kaplan-Meier survival curves with a log-rank test highlighted no significant differences in intravesical recurrence-free survival, cancer-specific survival, and overall survival among these approaches with P values of 0.987, 0.825, and 0.497, respectively. Multivariate analysis showed that the lower ureter location appears to have inferior intravesical recurrence-free survival (P = 0.042). However, cancer-specific survival and overall survival were independently influenced by tumor stage (hazard ratio [HR] = 8.439; 95% confidence interval: 2.424-29.377; P = 0.001) and lymph node status (HR = 14.343; 95%CI: 5.176-39.745; P < 0.001). CONCLUSION: All three techniques had comparable outcomes; although, EVBC and TUBC are minimally invasive. While based upon rather limited data, these findings will support urologists in blending experience with evidence to inform patient choices. However, larger, rigorously designed, multicenter studies with long term outcomes are still required.

14.
Int J Clin Exp Pathol ; 13(11): 2767-2771, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33284887

RESUMO

Collision tumor is a term denoting two histologically distinct tumor types occuring at the same anatomic site, which is a rare clinical entity. In the thyroid gland, collision tumors are rare. Here we report a case of the synchronous occurrence of follicular thyroid carcinoma (FTC) and papillary thyroid carcinoma (PTC). The current case report describes a 40-year-old woman with synchronous FTC and PTC. Pathologists and surgeons should be aware of collision tumors to avoid possible misdiagnosis.

15.
Materials (Basel) ; 13(23)2020 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-33291212

RESUMO

To reduce the thermal stress during the sublimation growth of 45 mm AlN single crystal, a tungsten sink was put on the top of the crucible lid. Numerical experiments showed that the radial temperature gradient was reduced due to the homogenization effect on temperature as a result of the sink. Therefore, this simple tungsten sink method has the potential to grow large-size AlN ingots with fewer cracks. It also reveals that enhancing the heat exchange of the crucible lid is an effective way to improve the quality of crystal growth.

16.
J Hazard Mater ; 408: 124810, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33360695

RESUMO

Recently, biogenic toxins have received increasing attention owing to their high contamination levels in feed and food as well as in the environment. However, there is a lack of an integrative platform for seamless linking of data-driven computational methods with 'wet' experimental validations. To this end, we constructed a novel platform that integrates the technical aspects of toxin biotransformation methods. First, a biogenic toxin database termed ToxinDB (http://www.rxnfinder.org/toxindb/), containing multifaceted data on more than 4836 toxins, was built. Next, more than 8000 biotransformation reaction rules were extracted from over 300,000 biochemical reactions extracted from ~580,000 literature reports curated by more than 100 people over the past decade. Based on these reaction rules, a toxin biotransformation prediction model was constructed. Finally, the global chemical space of biogenic toxins was constructed, comprising ~550,000 toxins and putative toxin metabolites, of which 94.7% of the metabolites have not been previously reported. Additionally, we performed a case study to investigate citrinin metabolism in Trichoderma, and a novel metabolite was identified with the assistance of the biotransformation prediction tool of ToxinDB. This unique integrative platform will assist exploration of the 'dark matter' of a toxin's metabolome and promote the discovery of detoxification enzymes.

17.
Huan Jing Ke Xue ; 41(12): 5458-5469, 2020 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-33374062

RESUMO

As an important primary producer, diatoms play a key role in aquatic ecosystems. However, little is known about the geographical distribution characteristics and driving factors of diatoms in large rivers. In this study, based on a high-throughput sequencing dataset of microeukaryotes, we analyzed the diversities and community compositions of planktonic and sedimentary diatoms in the 1200 km mainstream of Lancang River, a typical large river in southwestern China. The results showed that the diversities of planktonic and sedimentary diatoms in Lancang River were higher in the upstream natural section, and the community compositions of both groups were significantly different among different river sections. Dam construction had a significant effect on the dominant genera. Variance partitioning analysis showed that dispersal limitation was a major driving factor for the distribution pattern of planktonic and sedimentary diatoms, with explanation proportions of 16.7% and 29.8%. Co-occurrence network analyses showed that the interspecific competition relationship and network connectivity of the planktonic diatom network were stronger than the sedimentary ones. The network connectivity of planktonic and sedimentary diatoms in the cascade reservoir section was higher than that of the upstream natural section. This study will help to better understand the biogeographical distribution of diatoms in large rivers and provide useful information for ecological responses of diatoms to dam construction in rivers.


Assuntos
Diatomáceas , Rios , China , Ecossistema , Monitoramento Ambiental , Plâncton
18.
Life Sci ; 268: 118820, 2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-33278393

RESUMO

INTRODUCTION: Ischemia-reperfusion (I/R) injury causes present challenges in the field of graft transplantation which is also a major contributor to early graft dysfunction or failure after organ transplantation. The study focuses on the effects of prolonged cold-ischemia (CI) on the autophagic activity in the graft lung in a rat orthotopic lung transplantation model. MATERIAL AND METHODS: Donor lungs were preserved under CI conditions for different periods. An orthotopic lung transplantation model was developed, and the lung tissues from donor lungs subjected to CI preservation and reperfusion were harvested. We evaluated the effects of different CI periods on autophagy, reactive oxygen species (ROS) and glucose consumption. Additionally, the mechanism by which prolonged CI affected autophagy was investigated through determination of the molecules related to the mTOR pathway after treatment with 3-Methyladenine (3-MA), rapamycin and an adenosine triphosphate (ATP) synthase inhibitor oligomycin (OM). RESULTS: Prolonged CI led to increased activities of key glycolytic enzymes, glucose consumption and lactic acid production. Autophagy, ROS and glucose consumption were induced in the graft lung after I/R, which reached peak levels after 6 h and was gradually decreased. Most importantly, the perfusion treatment of 3-MA or OM decreased ROS level and autophagy, but increased the extent of mTOR phosphorylation, while the perfusion treatment of rapamycin induced ROS and autophagy. CONCLUSION: Taken together, autophagy mediated by a prolonged CI preservation affects the glucose consumption and ROS production in the graft lung via the mTOR signaling pathway.

19.
Nano Lett ; 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33347293

RESUMO

Mie-resonant dielectric metasurfaces are excellent candidates for both fundamental studies related to light-matter interactions and for numerous applications ranging from holography to sensing to nonlinear optics. To date, however, most applications using Mie metasurfaces utilize only weak light-matter interaction. Here, we go beyond the weak coupling regime and demonstrate for the first time strong polaritonic coupling between Mie photonic modes and intersubband (ISB) transitions in semiconductor heterostructures. Furthermore, along with demonstrating ISB polaritons with Rabi splitting as large as 10%, we also demonstrate the ability to tailor the strength of strong coupling by engineering either the semiconductor heterostructure or the photonic mode of the resonators. Unlike previous plasmonic-based works, our new all-dielectric metasurface approach to generate ISB polaritons is free from ohmic losses and has high optical damage thresholds, thereby making it ideal for creating novel and compact mid-infrared light sources based on nonlinear optics.

20.
J Magn Reson Imaging ; 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33300253

RESUMO

BACKGROUND: The prognostic significance of hyperperfusion after reperfusion therapy in patients with acute ischemic stroke (AIS) remains controversial. PURPOSE: To investigate the clinical factors associated with hyperperfusion, and the 90-day prognostic value of hyperperfusion after mechanical thrombectomy in AIS patients. STUDY TYPE: Retrospective. POPULATION/SUBJECTS: Fifty-four AIS patients who underwent mechanical thrombectomy. FIELD STRENGTH/SEQUENCE: Time-of-flight MR angiography, pulsed arterial spin labeling (ASL), diffusion-weighted imaging (DWI), and susceptibility-weighted imaging were performed at 3.0T within 1 week after thrombectomy. ASSESSMENT: Clinical factors including demographics, risk factors, stroke and treatment characteristics were collected and assessed. Hyperperfusion on ASL was defined as a focal increased cerebral blood flow on the affected side ≥130% of its mirror counterpart. Good clinical outcome at 90 days was defined as modified Rankin Scale score of 0-2. STATISTICAL TESTS: The interrater agreement was assessed using Cohen's kappa or the intraclass correlation coefficient. The relationship between hyperperfusion and clinical factors were analyzed by appropriate univariate statistics. Predictors of 90-day functional outcome were assessed by univariate analyses followed by multivariate logistic regression analysis and receiver-operating-characteristic curves. RESULTS: Thirty-six (66.7%) patients developed hyperperfusion on ASL after thrombectomy. Hyperperfusion was significantly correlated with successful recanalization (P < 0.05) and improvement of National Institutes of Health Stroke Scale scores at 24 hours (NIHSS24h ) (P < 0.05). A higher incidence of hemorrhage transformation was observed in patients with hyperperfusion than those without (63.9% vs. 50.0%), but no significant difference was found (P = 0.327). NIHSS24h (odds ratio [OR], 0.75, [95% confidence interval [CI] 0.62-0.91], P < 0.05), lesion volume on diffusion-weighted imaging (OR, 0.97, [95% CI 0.95-1.00], P < 0.05), and hyperperfusion on ASL (OR, 9.8, [95% CI 1.7-55.3], P < 0.05) were independent variables for predicting good functional outcomes. DATA CONCLUSION: Hyperperfusion on ASL correlated with successful recanalization and may be an independent prognostic marker for good neurological outcomes at 90 days in AIS patients after mechanical thrombectomy. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY STAGE: 2.

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