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1.
BMC Cancer ; 20(1): 974, 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33032547

RESUMO

BACKGROUND: Radiotherapy (RT) is the major part of the treatment strategy set by a multidisciplinary team (MDT) for patients diagnosed with esophageal cancer (EC). The effect of an MDT collaboration on patients with EC who underwent RT is unclear. METHODS: We retrospectively collected all patients diagnosed with EC in the radiation oncology department at our institution from January 2015 to May 2017. The patients were divided into groups based on if they had their cases presented or not presented at the MDT meeting (with MDT and non-MDT, respectively). Propensity score matching (PSM) was applied at a ratio of 1:1 and the nearest neighbor matching method to compare the two groups. RESULTS: A total of 212 consecutive patients were analyzed, including 157 with MDT and 55 non-MDT. In the unmatched population, the patients with MDT were more likely to received chemotherapy than the non-MDT patients (84.7% vs. 69.1%; × 2 = 6.373; P = 0.012).MDT-patients had significantly improved overall survival compared with non-MDT patients (p = 0.025). In the multivariate analysis, MDT was an independent prognostic factor for OS in patients with EC who underwent RT (P = 0.019, HR 0.59, 95% CI 0.38-0.92). After PSM for baseline characteristics, the benefit of MDT for OS became more obvious. Additionally, we also found that MDT was an independent predictor of receiving chemotherapy by using logistic regression analysis. CONCLUSION: In patients who underwent radiotherapy for esophageal cancer, MDT was an independent factor for overall survival, which probably due to the selection of multimodality treatment when compared to non-MDT setting.

3.
BMC Emerg Med ; 20(1): 77, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33023479

RESUMO

BACKGROUND: Sepsis-associated encephalopathy (SAE) is a common complication of sepsis that may result in worse outcomes. This study was designed to determine the epidemiology, clinical features, and risk factors of SAE. METHODS: This was a retrospective study of all patients with sepsis who were admitted to the Critical Care Medicine Department of Hangzhou First People's Hospital Affiliated with Zhejiang University School of Medicine from January 2015 to December 2019. RESULTS: A total of 291 sepsis patients were screened, and 127 (43.6%) were diagnosed with SAE. There were significant differences in median age, proportion of underlying diseases such as hypertension, Sequential Organ Failure Assessment (SOFA) score, Acute Physiology and Chronic Health Evaluation II (APACHE II) score, gastrointestinal infections, detection rate of Enterococcus, and 28-day mortality between the SAE and non-SAE groups. Both the SOFA score and APACHE II score were independent risk factors for SAE in patients with sepsis. All 127 SAE patients were divided into survival and non-survival groups. The age, SOFA score, and APACHE II score were independently associated with 28-day mortality in SAE patients. CONCLUSION: In the present retrospective study, nearly half of patients with sepsis developed SAE, which was closely related to poor outcomes. Both the SOFA score and APACHE II score were independent risk factors for predicting the occurrence and adverse outcome of SAE.

4.
BMC Pregnancy Childbirth ; 20(1): 592, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33023512

RESUMO

BACKGROUND: Hypertriglyceridemia-induced acute pancreatitis during pregnancy (HTG-APP) is a rare but severe disease with high maternal-fetal mortality risk, which constitutes a systemic inflammatory process accompanied by thrombosis and bleeding disorders. However, the role of mean platelet volume (MPV) in HTG-APP remains unclear. METHODS: In the retrospective study, we collected 45 patients with HTG-APP as the HTG-APP group and 49 pregnant females with hypertriglyceridemia as the control group. MPV and other relevant variables at onset and remission were collected and compared. RESULTS: MPV were significantly higher in the HTG-APP group than in the control group (P < 0.001), and lower in remission than on onset (P = 0.002). According to the severity of acute pancreatitis, all subjects were classified into mild AP (MAP), moderately severe AP (MSAP), and severe AP (SAP) groups. There was a significant difference in MPV on onset among the three groups (P = 0.048), and the SAP patients had the highest levels of MPV. In addition, only in the SAP group, MPV was lower in remission than on onset (P = 0.010). Logistic regression analyses revealed that MPV was significantly associated with SAP (odds ratio = 2.077, 95% confdence interval, 1.038-4.154; P = 0.039). CONCLUSIONS: These results may indicate an important role of mean platelet volume in evaluating the severity of HTG-APP.

5.
Ann Surg Oncol ; 2020 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-32974696

RESUMO

PURPOSE: The aim of this study was to evaluate the impact of time to radiotherapy (TTR) after completion of chemotherapy (CT), and TTR after surgery, in breast cancer (BC) patients. PATIENTS AND METHODS: Continuous breast cancer patients treated with surgery and CT followed by radiotherapy (RT) from 2009 through 2015 were retrospectively reviewed. Patients were categorized into four groups with respect to TTR after CT, i.e. <4, 4-8, 8-12, and >12 weeks, and TTR after surgery, i.e. <147, 147-180, 180-202, and >202 days. The Cox proportional hazards model was used to identify the independent effect of TTRs. RESULTS: Overall, 989 patients were enrolled. Patients with a TTR of >12 weeks after CT showed significantly worse breast cancer-specific survival (BCSS) and overall survival (OS) compared with those who had a TTR of <4 weeks (BCSS: hazard ratio [HR] 0.28, 95% confidence interval [CI] 0.1-0.76; OS: HR 0.33, 95% CI 0.13-0.88), 4-8 weeks (BCSS: HR 0.23, 95% CI 0.08-0.66; OS: HR 0.29, 95% CI 0.11-0.8), and 8-12 weeks (BCSS: HR 0.22, 95% CI 0.05-0.96; OS: HR 0.23, 95% CI 0.06-0.99). TTR after surgery showed no significant association with survival outcomes in the entire cohort, except in patients with hormone receptor (HR)-positive disease and those receiving mastectomy. In HR-positive tumors, a TTR after CT of >12 weeks remained an independent predictor for adverse BCSS and OS. CONCLUSION: Initiation of RT beyond 12 weeks after CT might compromise survival outcomes. Efforts should be made to avoid delaying RT, especially after completion of CT and in patients with HR-positive tumors, positive lymph nodes, and those receiving mastectomy.

6.
ACS Appl Mater Interfaces ; 12(38): 42511-42520, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32897691

RESUMO

Photothermal therapy (PTT) and photodynamic therapy (PDT) have emerged as highly prospective therapeutic modalities in cancer therapy. Notwithstanding, a critical challenge still remains in the exploration of an effective strategy to maximize the synergistic efficacy of PTT and PDT due to low photoconversion efficiency. Herein, inspired by the phospholipid bimolecular structure of the cell membrane, bionic cell membrane polymeric vesicles with photothermal/photodynamic synergy for prostate cancer therapy at one wavelength's excitation are constructed in one step by the coordination of hexadecyl trimethyl ammonium bromide (CTAB) from the surface of hydrophobic gold nanorods (AuNRs) with indocyanine green (ICG) and polycaprolactone (PCL), achieving their self-assembly in aqueous solutions. Importantly, the aggregation of the assembly improves the stability of the vesicles, realizing the synergistic effect of PTT and PDT for prostate cancer therapy. After being assembled within polymeric vesicles, bifunctional photosensitizer ICG can generate reactive oxygen species (ROS) and photothermal effect under light treatment. Their ROS not only induce PDT efficacy but also destroy the integrity of the lysosomal membrane, promoting the translocation of ICG and another photosensitizer called gold nanorods (AuNRs) into the cytosol. Moreover, their photothermal effects produced by both photosensitizers are able to engender greater damage to the tumor cells because of the close distance with organelles. This structure manifests good cellular uptake, highly effective tumor accumulation, high photothermal conversion efficiency, and excellent properties of enhanced photobleaching resistance, which are beneficial to ICG-based fluorescence tumor imaging. Using the same near-infrared (NIR) wavelength for excitation, the AuNR/ICG vesicles can reduce the side effect rate of photodamage on the skin. In addition, by generating reactive oxygen species (ROS) and double photothermal effect, the vesicles under NIR excitation can promote the apoptosis of PC3 tumor cells. Taken together, the spontaneous self-assembled AuNR/ICG vesicles exhibit huge potential in advanced-stage prostate cancer therapy, especially for the prostate-specific membrane antigen (PSMA)-negative castration-resistant subtype.

7.
Cell Death Discov ; 6: 84, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32963812

RESUMO

Sustained activation of NLRP3 inflammasome and release of neutrophil extracellular traps (NETs) impair wound healing of diabetic foot ulcers (DFUs). Our previous study reported that milk fat globule epidermal growth factor VIII (MFG-E8) attenuates tissue damage in systemic lupus erythematosus. However, the functional effect of MFG-E8 on "NLRP3 inflammasome-NETs" inflammatory loop in wound healing of diabetes is not completely elucidated. In this study, neutrophils from DFU patients are susceptible to undergo NETosis, releasing more NETs. The circulating levels of NET components neutrophil elastase and proteinase 3 and inflammatory cytokines IL-1ß and IL-18 were significantly elevated in DFU patients compared with healthy controls or diabetic patients, in spite of higher levels of MFG-E8 in DFU patients. In Mfge8 -/- diabetic mice, skin wound displayed exaggerated inflammatory response, including leukocyte infiltration, excessive activation of NLRP3 inflammasome (release of higher IL-1ß, IL-18, and TNF-α), largely lodged NETs, resulting in poor angiogenesis and wound closure. When stimulated with high-dose glucose or IL-18, MFG-E8-deficient neutrophils release more NETs than WT neutrophils. After administration of recombinant MFG-E8, IL-18-primed NETosis of WT or Mfge8 -/- neutrophils was significantly inhibited. Furthermore, NET and mCRAMP (component of NETs, the murine equivalent of cathelicidin LL-37 in human)-mediated activation of NLRP3 inflammasome and production of IL-1ß/IL-18 were significantly elevated in Mfge8 -/- macrophages compared with WT macrophages, which were also significantly dampened by the administration of rmMFG-E8. Therefore, our study demonstrated that as inhibitor of the "NLRP3 inflammasome-NETs" inflammatory loop, exogenous rMFG-E8 improves angiogenesis and accelerates wound healing, highlighting possible therapeutic potential for DFUs.

8.
Drug Dev Ind Pharm ; : 1-11, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-32895014

RESUMO

The aim of this study was to develop the Metformin Hydrochloride and Gliclazide (MH-GZ) sandwiched osmotic pump capsule which could overcome the problems associated with short half-life and burst release. The system could deliver drugs with different solubility simultaneously at zero-order rate, in which MH-GZ were filled in both sides of the push layer respectively. The single factor and orthogonal test were employed to obtain the optimized formulation with the evaluation index of similarity factor (ƒ2). R language was used to visualized analyze the main influence factors of drug release and their correlations. Pharmacokinetic study was performed in beagle dogs compared to the marketed conventional product, which showed decreased Cmax, prolonged Tmax, and improved bioavailability, independent of pH and agitational speed but related to osmotic pressure differences across the semi permeable membrane. The designed sandwiched osmotic pump capsule proposed a promising substitute for the marketed product for the treatment of type 2 diabetes.

9.
Artigo em Inglês | MEDLINE | ID: mdl-32985008

RESUMO

Quasi-1D metal halide perovskite nanorods (NRs) are emerging as a type of materials with remarkable optical and electronic properties. Research into this field is rapidly expanding and growing in the past several years, with significant advances in both mechanistic studies of their growth and widespread possible applications. Here, the recent advances in 1D metal halide perovskite nanocrystals (NCs) are reviewed, with a particular emphasis on NRs. At first, the crystal structures of perovskites are elaborated, which is followed by a review of the major synthetic approaches toward perovskite NRs, such as wet-chemical synthesis, substrate-assisted growth, and anion exchange reactions, and discussion of the growth mechanisms associated with each synthetic method. Then, thermal and aqueous stability and the linear polarized luminescence of perovskite NRs are considered, followed by highlighting their applications in solar cells, light-emitting diodes, photodetectors/phototransistors, and lasers. Finally, challenges and future opportunities in this rapidly developing research area are summarized.

10.
J Surg Res ; 256: 584-594, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32805581

RESUMO

BACKGROUND: Acute lung injury (ALI), manifested by progressive hypoxemia and respiratory distress, is associated with high morbidity and mortality, which lacks the effective therapies in clinics. Our previous studies demonstrated that maresin1 (MaR1), a specialized proresolving mediator, could effectively mitigate the inflammation of lipopolysaccharide (LPS)-induced ALI. However, whether MaR1 impacts the macrophage polarization to alleviate ALI remains unclear. Our study explored the effects and underlying mechanisms of MaR1 on the macrophage phenotypes in ALI. MATERIAL AND METHODS: Male BALB/c mice were subjected to endotracheal instillation of LPS to induce ALI and then intravenously injected with MaR1 or normal saline. Intraperitoneal administration of peroxisome proliferator-activated receptor-γ (PPAR-γ) inhibitor GW9662 was given 30 mins before MaR1. We measured the pathohistologic changes, pulmonary edema, inflammatory cytokines, and the flow cytometry of macrophage phenotypes. RESULTS: Our results illustrated that MaR1 ameliorated lung injury and increased monocyte or macrophage recruitment and the release of anti-inflammatory cytokines. The flow cytometry showed that MaR1 promoted polarization of CD11c-CD206+ (M2) macrophages and inhibited polarization of CD11c+CD206- (M1) macrophages. Besides, the western blotting revealed that MaR1 increased the expression of PPAR-γ. The pretreatment with PPAR-γ antagonist GW9662 could significantly suppress the polarization of M2 macrophages and antagonize the protective effects of MaR1 on LPS-stimulated ALI. CONCLUSIONS: MaR1 was able to promote M2 macrophage polarization by reversing LPS-mediated PPAR-γ inhibition, thereby expediting the recovery of LPS-stimulated ALI.

11.
Medicine (Baltimore) ; 99(30): e21189, 2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-32791694

RESUMO

BACKGROUND: The aim of the present study was to investigate the effectiveness of Extracorporeal Shock Wave (ECSW) in the treatment of lateral epicondylitis (LE) of humerus. HYPOTHESIS: ECSW therapy in people with LE effectively reduces the pain and gains functional rehabilitation. MATERIALS/METHODS: Databases of PubMed, EMBASE, Web of Science and the Cochrane Library from inception to April 2020 was searched to identify all relevant RCTs comparing ECSW therapy with any other conservative treatment, including injection and local anesthetic versus placebo or control in patients aged 18 with LE. The primary outcome is the mean overall pain score at 12 weeks after treatment. Another secondary outcome mainly included Thomsen test, 50% pain reduction, grip strength and adverse effect at 12 weeks after treatment. RESULTS: Nine studies were included in the meta-analysis. Compared with the placebo group, ECSW cannot significantly reduce the pain score (mean deviation [MD] = -4.23, 95% confidence interval [CI]: -8.78 to 0.32, P = .07), but make more people acquire 50% pain reduction (MD = 1.38, 95% CI: 1.09 to 1.75, P = .008). There was no significant difference between ECSW and control in decreasing the pain score of Thomsen test (MD = -3.22, 95% CI: -14.06 to 7.62, P = .56). ECSW was more effective in Grip strength as compared with control at 12 weeks-3 months (MD = 3.52, 95% CI: 2.43 to 4.60, P < .00001) CONCLUSIONS:: Results suggested that ECSW cannot effectively reduce the mean overall pain, but it showed more people acquire 50% pain reduction and might be a better option for the treatment of LE. Because of study limitations, additional high level of evidence, more rigorously designed large-samples and high-quality randomized controlled trials are needed to guide clinical practice.


Assuntos
Tratamento por Ondas de Choque Extracorpóreas , Cotovelo de Tenista/terapia , Tratamento por Ondas de Choque Extracorpóreas/efeitos adversos , Força da Mão , Humanos , Medição da Dor , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
Curr Med Sci ; 40(4): 773-785, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32862390

RESUMO

Renal cancer is a common genitourinary malignance, of which clear cell renal cell carcinoma (ccRCC) has high aggressiveness and leads to most cancer-related deaths. Identification of sensitive and reliable biomarkers for predicting tumorigenesis and progression has great significance in guiding the diagnosis and treatment of ccRCC. Here, we identified 2397 common differentially expressed genes (DEGs) using paired normal and tumor ccRCC tissues from GSE53757 and The Cancer Genome Atlas (TCGA). Then, we performed weighted gene co-expression network analysis and protein-protein interaction network analysis, 17 candidate hub genes were identified. These candidate hub genes were further validated in GSE36895 and Oncomine database and 14 real hub genes were identified. All the hub genes were up-regulated and significantly positively correlated with pathological stage and histologic grade of ccRCC. Survival analysis showed that the higher expression level of each hub gene tended to predict a worse clinical outcome. ROC analysis showed that all the hub genes can accurately distinguish between tumor and normal samples, and between early stage and advanced stage ccRCC. Moreover, all the hub genes were positively associated with distant metastasis, lymph node infiltration, tumor recurrence and the expression of MKi67, suggesting these genes might promote tumor proliferation, invasion and metastasis. Furthermore, the functional annotation demonstrated that most genes were enriched in cell-cycle related biological function. In summary, our study identified 14 potential biomarkers for predicting tumorigenesis and progression, which might contribute to early diagnosis, prognosis prediction and therapeutic intervention.

13.
Theranostics ; 10(16): 7163-7177, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32641985

RESUMO

Rationale: Kupffer cells (KCs) play a crucial role in liver immune homeostasis through interacting with other immune cells and liver sinusoidal endothelial cells (LSECs). However, how KCs exactly interact with these cells for maintaining the homeostasis still require the further investigation. CXCL10 is a chemokine that has been implicated in chemoattraction of monocytes, T cells, NK cells, and dendritic cells, and promotion of T cell adhesion to endothelial cells. Although CXCL10 is also known to participate in the pathogenesis of hepatic inflammation, the degree to which it is functionally involved in the crosstalk between immune cells and regulation of immune response is still unclear. Methods: To dynamically investigate the function of KCs, we used our recently developed rapid cell ablation model, intermedilysin (ILY)/human CD59 (hCD59)-mediated cell ablation tool, to selectively ablate KC pool under normal condition or concanavalin A (Con A)- induced hepatitis. At certain time points after KCs ablation, we performed flow cytometry to monitor the amount of hepatic infiltrating immune cells. mRNA array was used to detect the change of hepatic cytokines and chemokines levels. Cytokines and chemokines in the serum were further measured by LEGENDplexTM mouse proinflammatory chemokine panel and inflammation panel. Evans blue staining and transmission electron microscopy were used to investigate the interaction between KCs and LSECs in steady condition. CXCL10 neutralizing antibody and CXCL10 deficient mouse were used to study the role of CXCL10 in immune cell migration and pathogenesis of Con A-induced hepatitis. Results: At steady state, elimination of KCs results in a reduction of hepatic infiltrating monocytes, T, B, and NK cells and a list of cytokines and chemokines at transcriptional level. In the meantime, the depletion of KCs resulted in increased sinusoidal vascular permeability. In the pathological condition, the KCs elimination rescues Con A-induced acute hepatitis through suppressing proinflammatory immune responses by down-regulation of hepatitis-associated cytokines/chemokines in serum such as CXCL10, and recruitment of infiltrating immune cells (monocytes, T, B, and NK cells). We further documented that deficiency or blockade of CXCL10 attenuated the development of Con A-induced hepatitis associated with reduction of the infiltrating monocytes, especially inflammatory Ly6Chi monocytes. Conclusions: This study supports the notion that KCs actively interact with immune cells and LSECs for maintaining immune response and liver homeostasis. Our data indicate that the interplay between KCs and infiltrated monocytes via CXCL10 contribute to Con A-induced hepatitis.

14.
J Org Chem ; 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32668153

RESUMO

A highly efficient approach of visible-light-driven radical difluoromethylation of isocyanides to access a wide variety of difluoromethylated phenanthridines and isoquinolines is herein described. Electrophilic S-(difluoromethyl)diarylsulfonium salt proved to be a good difluoromethyl radical precursor under photoredox catalysis. A broad range of isocyanides were tolerated to furnish the corresponding difluoromethylated phenanthridines, isoquinolines, furo[3,2-c]pyridine, and pyrido[3,4-b]indole in moderate to excellent yields under mild conditions. A plausible mechanism was also proposed.

15.
J Hazard Mater ; 398: 122826, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-32506047

RESUMO

In this study, polycyclic aromatic hydrocarbons (PAHs) at practical concentrations in the simulated sludge treated by the Fe2+/H2O2 and Fe2+/peroxymonosulfate (PMS) systems were evaluated in terms of the PAHs (phenanthrene, anthracene, fluoranthene) removal, element migration, Cl- effect, and chlorination by-product formation. The results indicated that according to the removal rate of PAHs, the optimal dosage of the Fe2+/PMS system (∑PAHs removal rate was 64.66 ±â€¯2.82 %) was 1/30 of that for the Fe2+/H2O2 system (∑PAHs removal rate was 78.63 ±â€¯0.38 %). The elemental contents in the simulated sludge were mainly affected by the extent of advanced oxidation and the amount of generated iron flocs. By studying the PAHs removal, free chlorine formation, total organochlorine content, and PAHs products in Fe2+/H2O2/Cl- and Fe2+/PMS/Cl- systems, it was found that chlorine radicals (·Cl) had high reactivity with phenanthrene and fluoranthene, whereas dichloride anion radicals (Cl2·-) exhibited the opposite behavior. Furthermore, PAHs were oxidized by ·Cl and hydroxyl radical in the Fe2+/H2O2/Cl- system, whereas PAHs and their products were chlorinated by free chlorine and ·Cl in the Fe2+/PMS/Cl- system to six chlorinated by-products such as Cl-PAHs (9-Cl-phenanthrene, 2-Cl-anthracene, 9,10-Cl2-anthracene, 3-Cl-fluoranthene). These results provide some useful suggestions for the safe advanced oxidation process treatment of textile dyeing sludge.

16.
Int J Radiat Oncol Biol Phys ; 108(4): 1030-1039, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32585337

RESUMO

PURPOSE: The present study aimed to evaluate the effect of postmastectomy radiation therapy (PMRT) after neoadjuvant chemotherapy in patients with node-positive stage II to III (cT1-4N1-2M0) breast cancer. METHODS AND MATERIALS: A total of 1813 patients from 12 institutions were retrospectively reviewed. Patients were classified into 1 of 3 groups based on the pathologic lymph node status after neoadjuvant chemotherapy: ypN0, ypN1, and ypN2-3. The role of PMRT was separately evaluated in each group. Locoregional control, disease-free survival, and overall survival (OS) were estimated using the Kaplan-Meier method. The effect of PMRT was assessed by propensity score-matched analyses and multivariate Cox analyses. RESULTS: With a median follow-up of 72.9 months, 5-year locoregional control, disease-free survival, and OS rates were 86.3%, 68.4%, and 83.1% for the entire cohort, respectively. There were 490 (27.0%), 567 (31.3%), and 756 (41.7%) patients in the ypN0, ypN1, and ypN2-3 groups, respectively. PMRT significantly improved 5-year OS in the ypN2-3 group (74.2% vs 55.9%; P < .001) but had no effect on 5-year OS in the ypN0 group (93.1% vs 95.5%; P = .517) and ypN1 group (88.4% vs 87.8%; P = .549). CONCLUSIONS: With modern systemic therapy, PMRT significantly improved OS in the ypN2-3 group but not in the ypN0 and ypN1 groups. Whether PMRT can be safely omitted in the ypN0 and ypN1 groups should be addressed prospectively.

17.
J Phys Chem Lett ; : 4990-4997, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32498513

RESUMO

Polar surfaces of ionic crystals are of growing technological importance, with implications for the efficiency of photocatalysts, gas sensors, and electronic devices. The creation of ionic nanocrystals with high percentages of polar surfaces is an option for improving their efficiency in the aforementioned applications but is hard to accomplish because they are less thermodynamically stable and prone to vanish during the growth process. Herein, we develop a strategy that is capable of producing polar surface-dominated II-VI semiconductor nanocrystals, including ZnS and CdS, from copper sulfide hexagonal nanoplates through cation exchange reactions. The obtained wurtzite ZnS hexagonal nanoplates have dominant {002} polar surfaces, occupying up to 97.8% of all surfaces. Density functional theory calculations reveal the polar surfaces can be stabilized by a charge transfer of 0.25 eV/formula from the anion-terminated surface to the cation-terminated surface, which also explains the presence of polar surfaces in the initial Cu1.75S hexagonal nanoplates with cation deficiency prior to cation exchange reactions. Experimental results showed that the HER activity could be boosted by the surface polarization of polar surface-dominated ZnS hexagonal nanoplates. We anticipate this strategy is general and could be used with other systems to prepare nanocrystals with dominant polar surfaces. Furthermore, the availability of colloidal semiconductor nanocrystals with dominant polar surfaces produced through this strategy opens a new avenue for improving their efficiency in catalysis, photocatalysis, gas sensing, and other applications.

18.
Elife ; 92020 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-32511091

RESUMO

It has been suggested that Staufen (Stau) is key in controlling the variability of the posterior boundary of the Hb anterior domain (xHb). However, the mechanism that underlies this control is elusive. Here, we quantified the dynamic 3D expression of segmentation genes in Drosophila embryos. With improved control of measurement errors, we show that the xHb of stau- mutants reproducibly moves posteriorly by 10% of the embryo length (EL) to the wild type (WT) position in the nuclear cycle (nc) 14, and that its variability over short time windows is comparable to that of the WT. Moreover, for stau- mutants, the upstream Bicoid (Bcd) gradients show equivalent relative intensity noise to that of the WT in nc12-nc14, and the downstream Even-skipped (Eve) and cephalic furrow (CF) show the same positional errors as these factors in WT. Our results indicate that threshold-dependent activation and self-organized filtering are not mutually exclusive and could both be implemented in early Drosophila embryogenesis.

19.
Nan Fang Yi Ke Da Xue Xue Bao ; 40(2): 152-158, 2020 Feb 29.
Artigo em Chinês | MEDLINE | ID: covidwho-210111

RESUMO

OBJECTIVE: To analyze the evolution and variation of SARS-CoV-2 during the epidemic starting at the end of 2019. METHODS: We downloaded the full-length genome sequence of SARS-CoV-2 from the databases of GISAID and NCBI. Using the software for bioinformatics including MEGA-X, BEAST, and TempEst, we constructed the genomic evolution tree, inferred the time evolution signal of the virus, calculated the tMRCA time of the virus and analyzed the selection pressure of the virus during evolution. RESULTS: The phylogenetic tree showed that SARS-CoV-2 belonged to the Sarbecovirus subgenus of ß Coronavirus genus together with bat coronavirus BetaCoV/bat/Yunnan/RaTG13/2013, bat-SL-CoVZC45, bat-SL-CoVZXC21 and SARS-CoV. The genomic sequences of SARS-CoV-2 isolated from the ongoing epidemic showed a weak time evolution signal with an average tMRCA time of 73 days (95% CI: 38.9-119.3 days). No positive time evolution signal was found between SARS-CoV-2 and BetaCoV/bat/Yunnan/RaTG13/2013, but the former virus had a strong positive temporal evolution relationship with bat-SL-CoVZC45 and SARS-CoV. The major cause for mutations of SARS-CoV-2 was the pressure of purification selection during the epidemic. CONCLUSIONS: SARS-CoV-2 may have emerged as early as November, 2019, originating most likely from bat-associated coronavirus. This finding may provide evidence for tracing the sources and evolution of the virus.


Assuntos
Betacoronavirus/genética , Quirópteros , Infecções por Coronavirus/virologia , Genoma Viral , Pneumonia Viral/virologia , Animais , Evolução Biológica , China , Quirópteros/virologia , Coronavirus/genética , Infecções por Coronavirus/genética , Pandemias , Filogenia , Pneumonia Viral/genética , Sequenciamento Completo do Genoma
20.
J Clin Lab Anal ; 34(9): e23378, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32462718

RESUMO

BACKGROUND: Long non-coding RNAs (lncRNAs) perform pivotal regulatory roles in tumor development. Our previous work revealed that the lncRNA gastric cancer-associated transcript 3 (GACAT3) was significantly overexpressed and associated with tumor size and metastasis in gastric cancer. METHODS: Total RNAs were extracted from colorectal cancer (CRC) and reverse transcribed, and then quantitative real-time PCR (qRT-PCR) was conducted. Cell counting was performed to assess the effect of GACAT3 on CRC cell line proliferation. Bioinformatics prediction, dual luciferase assay, miRNA mimics, siRNAs, and transfection experiments were applied to determine whether GACAT3 and LINC00152 are reciprocally regulated by miR-103. The relationship between their expression levels and clinicopathological factors of patients was explored. A receiver operating characteristic (ROC) curve was used to assess the potential diagnostic value of GACAT3 and LINC00152. RESULTS: GACAT3 was identified to be highly expressed in CRC tissues and associated with cell proliferation. Furthermore, we demonstrated that GACAT3 acted as a competing endogenous RNA of LINC00152 and they were both regulated by miR-103. Moreover, analysis of clinicopathological characteristics revealed that GACAT3 and LINC00152 were positively correlated with the depth of invasion, TNM stage, lymph node metastasis, and CA19-9 level. Importantly, a combination of GACAT3 and LINC00152 showed a superior diagnostic capacity compared with the use of the two molecules alone. CONCLUSION: Our work shows that GACAT3 and LINC00152 are both overexpressed in CRC and they act as a ceRNA network. Therefore, our data suggest that GACAT3 and LINC00152 may be a promising potential diagnostic biomarker for CRC.

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