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1.
Cerebrovasc Dis ; : 1-8, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31578010

RESUMO

OBJECT: To investigate the association between p.R4810K variant and postoperative collateral formation (PCF) in patients with moyamoya disease. METHODS: The p.R4810K variant was detected in 254 Chinese moyamoya patients. Surgically treated 273 hemispheres with preoperative and postoperative digital subtraction angiography were included. PCF was evaluated on lateral and anteroposterior views using angiography. Univariate and multivariate logistic regression analyses were performed to determine the influence factors for PCF. RESULTS: Among 254 patients, 191 (75.2%) patients carried wild-type p.R4810K variant (GG) and 63 patients (24.8%) carried the heterozygous p.R4810K variant (GA). PCF was better in patients with GA than in patients with GG both on lateral views and anteroposterior views (p < 0.001 and p < 0.001). Over the median 7 months follow-up after discharge, good PCF was observed in 201 hemispheres (73.6%), and poor PCF was observed in 72 hemispheres (26.4%). The univariable logistic regression showed that patients with GA (OR 4.681; 95% CI 1.925-11.383; p = 0.001) was associated with good PCF. On the other hand, the increasing age (OR 0.971; 95% CI 0.952-0.989; p = 0.002) and the presence of hemorrhage (OR 0.189; 95% CI 0.096-0.374; p = 0.000) were associated with poor PCF. Multivariate logistic regression analyses of p.R4810K variant and clinical variables showed that GA (OR 3.671; 95% CI 1.452-9.283; p = 0.006) was associated with a good PCF, while the presence of hemorrhage (OR 0.258; 95% CI 0.065-0.362; p = 0.000) was identified as a predictor of poor PCF. CONCLUSIONS: The heterozygous p.R4810K variant was associated with better PCF.

2.
J Cell Biol ; 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31578224

RESUMO

Mechano-environment plays multiple critical roles in the control of mesenchymal stem cell (MSC) fate decision, but the underlying signaling mechanisms remain undefined. We report here a signaling axis consisting of PINCH-1, SMAD specific E3 ubiquitin protein ligase 1 (Smurf1), and bone morphogenetic protein type 2 receptor (BMPR2) that links mechano-environment to MSC fate decision. PINCH-1 interacts with Smurf1, which inhibits the latter from interacting with BMPR2 and consequently suppresses BMPR2 degradation, resulting in augmented BMP signaling and MSC osteogenic differentiation (OD). Extracellular matrix (ECM) stiffening increases PINCH-1 level and consequently activates this signaling axis. Depletion of PINCH-1 blocks stiff ECM-induced BMP signaling and OD, whereas overexpression of PINCH-1 overrides signals from soft ECM and promotes OD. Finally, perturbation of either Smurf1 or BMPR2 expression is sufficient to block the effects of PINCH-1 on BMP signaling and MSC fate decision. Our findings delineate a key signaling mechanism through which mechano-environment controls BMPR2 level and MSC fate decision.

3.
J Natl Compr Canc Netw ; 17(10): 1194-1202, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31590152

RESUMO

BACKGROUND: Provider experience, or clinical volume, is associated with improved outcomes in many complex healthcare settings. Despite increased complexity of anticancer therapies, studies evaluating physician-level experience and cancer treatment outcomes are lacking. METHODS: A population-based study was conducted of older adults (aged ≥66 years) diagnosed with B-cell non-Hodgkin's lymphoma in 2004 through 2011 using SEER-Medicare data. Analysis focused on outcomes in patients receiving rituximab, the first approved monoclonal anticancer immunotherapy. We hypothesized that lower physician experience using rituximab and managing its infusion-related reactions would be associated with early treatment discontinuation. A 12-month look-back from each initiation of rituximab was used to categorize physician volume (0, 1-2, or ≥3 initiations per year). Modified Poisson regression was used to account for provider-level correlation and estimated relative risk (RR) of early rituximab discontinuation (<3 cycles within 180 days of rituximab initiation). Cox proportional hazards were used to measure the impact of rituximab discontinuation on survival. RESULTS: Among 15,110 patients who initiated rituximab with 2,684 physicians, 7.6% experienced early rituximab discontinuation. Approximately one-fourth of patients (26.1%) initiated rituximab with a physician who had no rituximab initiations during the preceding 12 months. Compared with patients treated by physicians who had ≥3 rituximab initiations in the prior year, those treated by physicians without initiations were 57% more likely to experience early discontinuation (adjusted RR [aRR], 1.57; 95% CI, 1.35-1.82; P<.001 for 0 vs ≥3, and aRR, 1.19; 95% CI, 1.03-1.37; P=.02 for 1-2 vs ≥3). Additionally, rituximab discontinuation was associated with higher risk of death (adjusted hazard ratio, 1.39; 95% CI, 1.28-1.52; P<.001). CONCLUSIONS: Lower oncologist experience with rituximab was associated with increased risk of early rituximab discontinuation in Medicare beneficiaries with non-Hodgkin's lymphoma. Physician-level volume may be an important factor in providing high-quality cancer care in the modern era.

4.
Medicine (Baltimore) ; 98(38): e16991, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31567936

RESUMO

BACKGROUND: Interleukin 12 (IL-12) and interleukin 12 receptor (IL12R), key inflammatory cytokines in the immune system, participate in bridging the innate immunity and adaptive immunity. No previous work has reported the role of IL-12 and IL12R in high-risk human papillomavirus (hrHPV) susceptibility. The purpose of this study was to investigate the association of IL-12, IL12R polymorphisms, and serum IL-12 levels with hrHPV susceptibility in rural women from Luohe, Henan, China. METHODS: Two hundred sixty cases with hrHPV infection and 260 healthy controls were selected. Enzyme-linked immunosorbent assays were used to detect the serum IL-12 levels, and the polymorphisms of IL12B rs3212227, IL12RB1 rs393548, and IL12RB1 rs436857 were determined using DNA sequencing. RESULTS: The serum IL-12 levels were significantly lower in cases with hrHPV infection compared with those in healthy controls (P < .01).There was no significant difference in IL12 rs3212227, IL12RB1rs436857, and IL12RB1rs393548 genotype and allele frequencies between cases and controls (P > .05). Furthermore, with respect to the IL12 rs3212227 polymorphism with serum IL-12 levels, although serum IL-12 levels were lower in cases than in controls, we did not find any differences between serum IL-12 levels and genotypes in cases(P > .05). CONCLUSIONS: Our data demonstrates that low serum IL-12 levels may be associated with hrHPV susceptibility but are not associated with IL-12 gene polymorphisms; furthermore, IL-12 and IL12R gene polymorphisms may not contribute susceptibility to hrHPV in rural women from Luohe, Henan, China.


Assuntos
Predisposição Genética para Doença , Subunidade p40 da Interleucina-12/genética , Infecções por Papillomavirus/genética , Receptores de Interleucina-12/genética , Adulto , Idoso , Grupo com Ancestrais do Continente Asiático , Estudos de Casos e Controles , China , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Subunidade p40 da Interleucina-12/sangue , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Receptores de Interleucina-12/sangue , População Rural
5.
Zhongguo Zhong Yao Za Zhi ; 44(14): 2943-2946, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31602837

RESUMO

Hugan Tablets is a Chinese patent medicine,it has the function of anti-inflammation and reducing transaminase. Based on questionnaire investigation of doctors and a systematic review of research literature on Hugan Tablets,using international clinical practice guidelines' developing methods,with the best available evidence and fully combining expert experience,and following the principle of " evidence-based,consensus-based and experience-based",Expert consensus statement on Hugan Tablets in clinical practice was developed by more than 30 multidisciplinary experts from the nationwide,aimed at guiding and standardizing the rational use of Hugan Tablets by clinicians and to improve clinical efficacy and safety. The expert consensus adopts internationally recognized recommendation criteria for classification of evidence: GRADE. The formation of expert consensus adopts the nominal group technique. Six main considerations are quality of evidence,curative effect,safety,economical efficiency,patient acceptability and other factors. If there is sufficient evidence,a " recommendation" is formed,using GRADE grid voting rule. If there isn' t sufficient evidence,a " consensus opinion" is formed,using majority counting rule. Focus on the indication,usage and dosage,drug use in special population and safety of Hugan Tablets,two recommendations and eight consensus opinions were put forward. Through expert meetings and correspondence,a nationwide consultation and peer review was conducted. This consensus applies to clinicians in hospitals and grass-roots health services,to provide guidance and reference for the rational use of Hugan Tablets.

6.
Epidemiology ; 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31596791

RESUMO

BACKGROUND: The observance of non-random space-time groupings of childhood cancer has been a concern of health professionals and the general public for decades. Many childhood cancers are suspected to have initiated in utero; therefore, we examined the spatial-temporal randomness of the birthplace of children who later developed cancer. METHODS: We performed a space-time cluster analysis using birth addresses of 5,896 cases and 23,369 population-based, age-, sex- and race/ethnicity-matched controls in California from 1997-2007, evaluating 20 types of childhood cancer and three a priori designated subgroups of childhood acute lymphoblastic leukemia (ALL). We analyzed data using a newly designed semiparametric analysis program, ClustR, and a common algorithm, SaTScan. RESULTS: We observed evidence for non-random space-time clustering for ALL diagnosed at 2-6 years of age in the South San Francisco Bay Area (ClustR p=0.04, SaTScan p=0.07), and malignant gonadal germ cell tumors in a region of Los Angeles (ClustR p=0.03, SaTScan p=0.06). ClustR did not identify evidence of clustering for other childhood cancers, though SaTScan suggested some clustering for Hodgkin lymphoma (p=0.09), astrocytoma (p=0.06) and retinoblastoma (p=0.06). CONCLUSION: Our study provides evidence that childhood ALL diagnosed at 2-6 years and malignant gonadal germ cell tumors sporadically occurs in non-random space-time clusters. Further research is warranted to identify epidemiologic features that may inform the underlying etiology.

7.
Leuk Lymphoma ; : 1-12, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31570040

RESUMO

Population level survival of patients with myelodysplastic syndromes (MDS) treated with hypomethylating agents (HMA) is inferior to clinical trials. Using SEER-Medicare data, we identified 2086 MDS patients diagnosed in 2004-13, aged ≥66 years at diagnosis, and receiving ≥1 HMA cycle after 2005. We used multivariate logistic regression and Cox proportional hazards models to assess the impact of provider experience on persistent HMA therapy and overall survival (OS), respectively. Median number of HMA cycles was 4 and median OS was 10 months. Thirty-two percent of patients were treated by providers with ≥1 prior HMA initiation in the last 2 years and were more likely to receive ≥4 cycles of HMA therapy (OR = 1.29, 95% CI = 1.06-1.57; p = .01). No significant association was found between MDS or HMA initiation volume and survival. In conclusion, while HMA initiation volume was associated with persistent HMA treatment, neither MDS nor HMA initiation volumes were associated with OS in older MDS patients.

8.
Plant Sci ; 287: 110188, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31481229

RESUMO

9-cis-epoxycarotenoid dioxygenase (NCED) is a rate-limiting enzyme for abscisic acid (ABA) biosynthesis. However, the molecular mechanisms of NCED5 that modulate plant development and abiotic stress tolerance are still unclear, particular in rice. Here, we demonstrate that a rice NCED gene, OsNCED5, was expressed in all tissues we tested, and was induced by exposure to salt stress, water stress, and darkness. Mutational analysis showed that nced5 mutants reduced ABA level and decreased tolerance to salt and water stress and delayed leaf senescence. However, OsNCED5 overexpression increased ABA level, enhanced tolerance to the stresses, and accelerated leaf senescence. Transcript analysis showed that OsNCED5 regulated ABA-dependent abiotic stress and senescence-related gene expression. Additionally, ectopic expression of OsNCED5 tested in Arabidopsis thaliana altered plant size and leaf morphology and delayed seed germination and flowering time. Thus, OsNCED5 may regulate plant development and stress resistance through control of ABA biosynthesis. These findings contribute to our understanding of the molecular mechanisms by which NCED regulates plant development and responses to abiotic stress in different crop species.

9.
Pathol Oncol Res ; 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31482398

RESUMO

Retinoblastoma (RB) is a malignant intraocular tumor that frequently occurs in infants and toddlers. Although the most of RB patients in the developed countries could survival from this cancer, the patients in undeveloped areas are still suffering. The human retinal pigment epithelial cell line ARPE-19 and human retinoblastoma (RB) cell lines HXO-RB44, Y79, and WERI-Rb1 were cultured. The mRNA levels of BANCR and miR-204-3p in these cell lines were measured by qRT-PCR. After transfection with sh-BANCR or treatment with miR-204-3p inhibitor in Y79 cells, the cell proliferation rate, growth, invasion, migration, apoptosis and Wnt/ß-catenin signaling pathway activity were measured. The regular Y79 and Y79 cells stably expressed sh-BANCR were injected subcutaneously into nude mice, respectively. The volumes and pathohistological futures of tumors were compared. The biochemical features similar to the cell culture were detected and compered. The mRNA measurements showed that BANCR negatively modulate miR-204-3p expression via directly integration with it. Besides, miR-204-3p and Wnt/ß-catenin signalling pathway were found to participate in the oncogenic effects of BANCR on RB cell line by Hoechst staining, cell Counting Kit-8 (CCK-8) assay, wound healing assay, transwell assay, and Western blot analysis in vitro. In addition, an in vivo tumorigenesis experiment in nude mice injected with Y79 cells stably expressed sh-BANCR conformed in the effects of BANCR on RB. Taken together, the knockdown of BANCR inhibited cell proliferation, apoptosis, invasion, and migration in RB via targeting miR-204-3p, the mechanism may involve inhibiting Wnt/ß-catenin signaling pathway.

10.
Cancer ; 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31483484

RESUMO

BACKGROUND: The majority of patients with acute myeloid leukemia (AML) are aged >65 years at the time of diagnosis and are not actively treated. The objective of the current study was to determine the prevalence, temporal trends, and factors associated with no active treatment (NAT) among older patients with AML in the United States. METHODS: A retrospective analysis was performed of Surveillance, Epidemiology, and End Results (SEER)-Medicare data from 14,089 patients with AML residing in the United States who were diagnosed with AML at age ≥66 years during 2001 through 2013. NAT was defined as not receiving any chemotherapy, including hypomethylating agents. Multivariable logistic regression models were used to analyze sociodemographic, clinical, and provider characteristics associated with NAT. RESULTS: The percentage of patients with NAT decreased over time from 59.7% among patients diagnosed in 2001 to 42.8% among those diagnosed in 2013. The median overall survival for the entire cohort was 82 days from the time of diagnosis. Patients treated with NAT had worse survival compared with those receiving active treatment. Variables found to be associated with higher odds of NAT included older age, certain sociodemographic characteristics (household income within the lowest quartile, residence outside the Northeast region of the United States, and being unmarried), and clinical factors (≥3 comorbidities, the presence of mental disorders, recent hospitalization, and disability). CONCLUSIONS: Greater than one-half of older patients with AML residing in the United States do not receive any active leukemia-directed therapy despite the availability of lower intensity therapies such as hypomethylating agents. Lack of active therapy receipt is associated with inferior survival. Identifying predictors of NAT might improve the quality of care and survival in this patient population, especially as novel therapeutic options with lower toxicity are becoming available.

11.
Math Biosci Eng ; 16(5): 5652-5671, 2019 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-31499730

RESUMO

Deflection is a crucial indicator to reflect the operating condition of girder bridges, which can be used to evaluate structure condition and identify abnormal loading. The paper analyzed the deflection characteristics of long-span girder bridges based on the coupling vibration between stochastic traffic stream and bridge. First, the latest research advances were integrated to form an analytical model of the coupling vibration between stochastic traffic stream and bridge. Then, a generalized Pareto distribution model based on peaks-over-threshold theory was established to predict the extreme girder deflection. Next, a cellular automaton based microsimulation method was proposed to model the traffic loads on bridges, which utilized the intelligent driver car-following model and acceptance distance based lane-changing model. Finally, these theories were applied in the case study of a long-span prestressed concrete continuous girder bridge. It is discovered from the study that, under the coupling vibration between stochastic traffic stream and bridge, the predicted extreme deflection of the case bridge is far lower than the specified design value. Hence, a grading warning model was established and employed to the analysis of deflection monitoring data of the bridge, showing a wide potential prospect of application.

12.
Med Sci Monit ; 25: 6649-6659, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31484919

RESUMO

BACKGROUND Chondrocyte dysfunction and apoptosis are 2 major features during the progression of osteoarthritis. Catalpol, an iridoid glycoside isolated from the root of Rehmannia, is a valuable medication with anti-inflammatory, anti-oxidative, and anti-apoptotic effects in various diseases. However, whether catalpol protects against osteoarthritis has not been investigated. MATERIAL AND METHODS To assess the role of catalpol in osteoarthritis and the potential mechanism of action, chondrocytes were treated with interleukin (IL)-1ß and various concentrations of catalpol. Catabolic metabolism, apoptotic level and relative signaling pathway were measured by western blot, real-time polymerase chain reaction and immunofluorescence staining. Meanwhile, we assess the cartilage degeneration in an experimental rat model using Safranin O fast green staining and cartilage was graded according to the Osteoarthritis Research Society International (OARSI) system. RESULTS The results showed that catalpol prevented chondrocyte apoptotic level triggered by IL-1ß, suppressed the release of catabolic enzymes, and inhibited the degradation of extracellular matrix induced by IL-1ß. Catalpol also inhibited the nuclear factor kappa B (NF-kappaB) pathway, reduced the production of inflammatory cytokines (IL-6, tumor necrosis factor-alpha) in IL-1ß-treated chondrocytes, and partially reversed cartilage degeneration in the knee joint in animal model of osteoarthritis. CONCLUSIONS Our work suggested that catalpol treatment attenuates IL-1ß-induced inflammatory response and catabolism in rat chondrocytes by inhibiting the NF-kappaB pathway, suggesting the therapeutic potential of catalpol for the treatment of osteoarthritis.

13.
PLoS One ; 14(9): e0222414, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31513664

RESUMO

The hierarchical modular organization of functional networks in the brain is crucial for supporting diverse cognitive functions. Functional disorders in the brain are associated with an abnormal hierarchical modular organization. The default mode network (DMN) is a complex dynamic network that is linked to specialized cognitive functions and clinically relevant information. In this study, we hypothesize that hierarchical functional segregation and integration of the DMN within attention-deficit/hyperactivity disorder (ADHD) is abnormal. We investigated topological metrics of both segregation and integration in different hierarchical subnetworks of the DMN between patients with ADHD and healthy controls. We found that the hierarchical functional integration and segregation of the DMN decreased and increased, respectively, in ADHD. Our results also indicated that the abnormalities in the DMN are intrinsically caused by changes in functional segregation and integration in its higher-level subnetworks. To better understand the temporally dynamic changes in the hierarchical functional integration and segregation of the DMN within ADHD, we further analyzed the dynamic transitions between functional segregation and integration. We found that the adaptive reorganizational ability of brain network states decreased in ADHD patients, which indicated less adaptive regulation between the DMN subnetworks in ADHD for supporting correspondingly normal cognitive function. From the perspective of hierarchical functional segregation and integration, our results further provide evidence to support dysfunctional brain cognitive functions within ADHD linked to brain network segregation and integration.

14.
Mikrochim Acta ; 186(10): 683, 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31529296

RESUMO

A boronate-modified magnetic affinity sorbent was prepared by adopting hyperbranched polyethyleneimine as the scaffold to amplify initiator sites. 3-Acrylamidophenylboronic acid was employed as monomer to proceed in situ free-radical polymerization on magnetite (Fe3O4) nanoparticles. Due to the improved density of boronic acid polymers, the adsorbent exhibited high adsorption capacity, typically (134 ± 8) µg mg-1 for dopamine, (92 ± 7) µg mg-1 for catechol, (363 ± 14) µg mg-1 for ovalbumin and (464 ± 22) µg mg-1 for horseradish peroxidase. These capacities are much higher than those of other adsorbents. The sorbent was applied to the enrichment of catecholamines from spiked human urine. Owing to the high adsorption capacity, only 1.0 mg of adsorbent was sufficient to eliminate the interferences and enrich the targets (dopamine, norepinephrine and epinephrine) within 5 min. They were quantified by HPLC. The recoveries from spiked samples range between 83.5% ~106%, with relative standard deviations of 3.2 ~ 9.4% (n = 5). The separation of glycoproteins from egg white was also accomplished prior to their analysis by PAGE. In the authors' perception, this approach is promising in that the density of functional groups on the adsorbent is strongly increased. Graphical abstract The preparation routine of boronate affinity magnetic adsorbent (Fe3O4@HpAAPBA). The adsorbent is used for the magnetic solid phase extraction of cis-dol compounds from real sample.

16.
Pathol Res Pract ; 215(10): 152616, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31493939

RESUMO

OBJECTIVES: To explore the expression level and to investigate the clinical associations of the long non-coding RNA (lncRNA) FAM83H-AS1 in gastric cancer. METHODS: The expression level of FAM83H-AS1 were explored by quantitative reverse transcription PCR (qRT-PCR). The Cox regression models as well as log-rank test were utilized to investigate whether FAM83H-AS1 expression could be used as a prognosis predictor. The value of FAM83H-AS1 as a diagnostic biomarker was evaluated by receiver operating curves (ROC). RESULTS: Aberrantly upregulation of FAM83H-AS1 was identified in gastric cancer in comparison with that in normal tissues. We also found that upregulated FAM83H-AS1 was a risk factor relating to OS and DFS. The area under curve (AUC) was 0.8603 and 0.6778 for gastric cancer and lymph node metastasis, respectively. CONCLUSION: Our results indicated that FAM83H-AS1 may function as an oncogene in gastric cancer and could be used as a prognosis predictor or diagnostic biomarker in gastric cancer.

17.
Clin Cancer Res ; 2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31548341

RESUMO

Tagraxofusp-erzs (Elzonris, Stemline) is a cytotoxin that targets CD123-expressing cells. On December 21, 2018, FDA approved tagraxofusp-erzs for the treatment of blastic plasmacytoid dendritic cell neoplasms (BPDCN) in adult and pediatric patients 2 years and older. Approval was based on the response rate in a single-arm trial, Study STML-401-0114; the pivotal cohort included 13 patients with treatment-naïve BPDCN who received tagraxofusp-erzs monotherapy. The complete response or clinical complete response (CR/CRc) rate in the pivotal cohort was 54% (95% CI: 25%, 81%), and the median duration of CR/CRc was not reached with a median follow-up of 11.5 months (range: 0.2, 12.7). In a separate exploratory cohort, a CR/CRc was achieved by 2 (13%) patients with R/R BPDCN. Safety was assessed in 94 patients with myeloid neoplasms treated with tagraxofusp-erzs at the approved dose and schedule. The major toxicity was capillary leak syndrome (CLS), which occurred in 55% of patients and was fatal in 2%. Hepatotoxicity and hypersensitivity reactions were reported in 88% and 46% of patients, respectively. Other common (≥ 30%) adverse reactions were nausea, fatigue, peripheral edema, pyrexia and weight increase. A high proportion of patients (85%) developed neutralizing anti-drug antibodies. Tagraxofusp-erzs is the first FDA-approved treatment for BPDCN.

18.
J Phys Chem Lett ; 10(19): 5687-5693, 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31495169

RESUMO

Two-dimensional (2D) hybrid organic-inorganic metal halide perovskites (HOIPs) with considerably hydrophobic phenyl ethylammonium (PEA) organic cations have been used in highly efficient solar cells and LEDs, which are stable and enjoy a long lifetime, even when exposed to moisture. Different from other 2D HOIPs with alkyl amine cations, a benzene ring is present in the PEA cation. Until recently, an understanding of the effects of PEA on the structural, electronic, and optical properties of 2D HOIPs under pressure has remained limited. We find that there is a direct-indirect band gap transition at around 5.8 GPa and that the direct band gap recovers when the pressure is released. The stacking order of the benzene rings in the PEA cation plays a critical role in the mechanical and electronic properties. Our present work demonstrates that 2D HOIPs with organic cations containing benzene rings prove highly attractive for use in flexible optoelectronics.

19.
Chem Asian J ; 2019 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-31515953

RESUMO

Solid-state acid-responsive materials are promising for the tunability of their intrinsic properties. However, the relationship between molecular structure and emission shift as a response to acid stimuli has not been systematically studied. Herein, we report the effect of protonation and subsequent intramolecular hydrogen bonding on the photophysical properties of compounds (MPP-s, MPP-d, and MPP-d-CN) with different conjugation modes between the electron-donating dimethoxyl phenyl and the electron-withdrawing benzothiazole ring. The results established that the stronger the intramolecular charge transfer feature of the compound, the smaller is the emission shift after acid stimuli. Our studies also indicated that the conjugation mode significantly affected the solid-state packing mode: MPP-s and MPP-d tended to form dimers, while MPP-d-CN exhibited the strongest aggregation-induced emission enhancement (AIEE). The exploration of structure-property relationship would provide experimental and theoretical guidance in designing acid-responsive molecular switches and developing high-performance AIEE-active luminogens.

20.
J Clin Invest ; 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31503548

RESUMO

Beclin 1 (Becn1) is a key molecule of the autophagy pathway and has been implicated in cancer development. Due to the embryonic lethality of Becn1 homozygous deficient mice, the precise mechanisms and cell-type-specific role of Becn1 in the regulation of inflammation and tumor immunity remain elusive. Here, we report that myeloid-deficient Becn1 (Becn1ΔM) mice develop neutrophilia and hypersusceptible to LPS-induced septic shock, with a high risk of developing spontaneous precursor (pre)-B cell lymphoma with elevated expressions of immunosuppressive molecules PD-L1 and IL-10. Becn1 deficiency results in stabilization of neutrophil MEKK3, aberrant p38 activation, and neutrophil-B cell interaction through Cxcl9/Cxcr3 chemotaxis. Neutrophil-B cell interplay leads to activations of IL-21/STAT3/IRF1 and CD40L/ERK signaling, together regulates the programmed death ligand 1 (PD-L1) expression, and suppresses CD8+ T cell function. Ablation of p38 in Becn1ΔM mice prevents neutrophil-inflammation and B cell tumorigenesis. Importantly, low Becn1 expression in human neutrophils correlates with PD-L1 levels in pre-B ALL patients. Our findings have identified myeloid Becn1 as a therapeutic target of cancer immunity and immunotherapy for pre-B lymphomas.

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