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1.
Mol Ecol ; 2021 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-34510615

RESUMO

The evolutionary outcomes of high-elevation adaptation have been extensively described. However, whether widely distributed high-elevation endemic animals adopt uniform mechanisms during adaptation to different elevational environments remains unknown, especially with respect to extreme high elevation environments. To explore this, we analyze phenotypic and genomic data of seven populations of plateau zokor (Myospalax baileyi) along elevations ranging from 2700 to 4300 m. Based on whole-genome sequencing data and demographic reconstruction of the evolutionary history, we show that two populations of plateau zokor living at elevations exceeding 3700 m diverged from other populations nearly ten thousand years ago. Further, phenotypic comparisons reveal stress-dependent adaptation, as two populations living at elevations exceeding 3700 m have elevated ratios of heart mass to body mass relative to other populations, and the highest population (4300 m) displays alterations in erythrocytes. Correspondingly, genomic analysis of selective sweeps indicates that positive selection might contribute to the observed phenotypic alterations in these two extremely high-elevation populations, with the adaptive cardiovascular phenotypes of both populations possibly evolving under the functional constrains of their common ancestral population. Taken together, phenotypic and genomic evidence demonstrates that heterogeneous stressors impact adaptations to extreme elevations and reveals stress-dependent and genetically constrained adaptation to hypoxia, collectively providing new insights into the high-elevation adaptation.

2.
J Agric Food Chem ; 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34523907

RESUMO

Plant pathogenic fungi seriously threaten agricultural production. There is an urgent need to develop novel fungicides with low toxicity and high efficiency. In this study, we designed and synthesized 44 pyrazolo[3,4-d]pyrimidin-4-one derivatives and evaluated them for their fungicidal activities. The bioassay data revealed that most of the target compounds possessed moderate to high in vitro antifungal activities. Especially compound g22 exhibited remarkable antifungal activity against Sclerotinia sclerotiorum with an EC50 value of 1.25 mg/L, close to that of commercial fungicide boscalid (EC50 = 0.96 mg/L) and fluopyram (EC50 = 1.91 mg/L). Moreover, compound g22 possessed prominent protective activity against S. sclerotiorum in vivo for 24 h (95.23%) and 48 h (93.78%), comparable to positive control boscalid (24 h (96.63%); 48 h (93.23%)). Subsequent studies indicated that compound g22 may impede the growth and reproduction of S. sclerotiorum by affecting the morphology of mycelium, destroying cell membrane integrity, and increasing cell membrane permeability. In addition, the application of compound g22 did not injure the growth or reproduction of Italian bees. This study revealed that compound g22 is expected to be developed for efficient and safe agricultural fungicides.

3.
J Biomech ; 127: 110703, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34481186

RESUMO

Proximal Optimization Technique (POT)is a post-expansion technique that must be completed after single-stent implantation for the coronary bifurcation. The optimal location for the distal balloon shoulder during POT remains debatable. In the present study, the finite element method is applied to simulate POT after single-stent implantation in the coronary bifurcation. Three different balloon locations based on the distal shoulder relative to the carina cut plane were analyzed: 1) "proximal":1mm before carina cut plane; 2) "standard": at the carina cut plane; and 3) "distal": 1 mm after the carina cut plane. The computational results showed differences in stent, vessel morphology, and vessel wall stress due to the different balloon locations. However, when distal balloon shoulder was located between two adjacent stent rings, it formed the distal cell of the stent, the best stent apposition, least stent structs obstruction at SB ostial. Moreover, best opening effect of distal cell of the stent can be achieved, with the least damage to the vessel wall.

4.
Elife ; 102021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34498587

RESUMO

Cyclic-di-guanosine monophosphate (c-di-GMP) is an important effector associated with acute-chronic infection transition in Pseudomonas aeruginosa. Previously, we reported a signaling network SiaABCD, which regulates biofilm formation by modulating c-di-GMP level. However, the mechanism for SiaD activation by SiaC remains elusive. Here we determine the crystal structure of SiaC-SiaD-GpCpp complex and revealed a unique mirror symmetric conformation: two SiaD form a dimer with long stalk domains, while four SiaC bind to the conserved motifs on the stalks of SiaD and stabilize the conformation for further enzymatic catalysis. Furthermore, SiaD alone exhibits an inactive pentamer conformation in solution, demonstrating that SiaC activates SiaD through a dynamic mechanism of promoting the formation of active SiaD dimers. Mutagenesis assay confirmed that the stalks of SiaD are necessary for its activation. Together, we reveal a novel mechanism for DGC activation, which clarifies the regulatory networks of c-di-GMP signaling.

5.
Exp Cell Res ; 407(2): 112784, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34508746

RESUMO

Inflammation is an essential factor contributing to sepsis-induced endothelial cell (EC) activation. Interleukin-35 (IL-35) is an anti-inflammatory/immunosuppressive cytokine that exerts protective effects on many inflammatory diseases. In this study, we investigated the effects of IL-35 on lipopolysaccharide (LPS)-induced EC activation and the potential underlying mechanism. Human umbilical vein endothelial cells (HUVECs) were incubated with LPS (1 µg/ml) for 24 h and then cocultured with different concentrations (0, 1, 10, or 100 ng/ml) of recombinant human IL-35 (rhIL-35) for 12 h. Flow cytometry analysis revealed that IL-35 inhibited LPS-induced HUVEC apoptosis in a dose-dependent manner. RT-qPCR and Western blot analyses showed significantly higher mRNA and protein levels of the adhesion molecules intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) and the inflammatory factors IL-6 and IL-8 in the LPS group than in the control group. These changes were alleviated by IL-35 treatment, suggesting that IL-35 protects ECs by downregulating inflammation. Furthermore, IL-35 induced signal transducer and activator of transcription 1 (STAT1) and STAT4 activation and promoted their interaction. Blocking STAT1 or STAT4 expression by fludarabine (STAT1 inhibitor) treatment or siRNA-STAT4-interfering fragment transfection inhibited the protective effect of IL-35 on ECs. Moreover, we observed a similar protective effect of IL-35 treatment on ECs in a mouse sepsis model induced by intraperitoneal LPS injection. This study indicated that IL-35 exerts anti-inflammatory and antiapoptotic effects on LPS-induced EC activation by activating the STAT1 and STAT4 signaling pathways.

6.
J Phys Chem Lett ; : 8847-8854, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34494851

RESUMO

Designing efficient organic photovoltaic (OPV) materials purposefully is still challenging and time-consuming. It is of paramount importance in material development to identify basic functional units that play the key roles in material performance and subsequently establish the substructure-property relationship. Herein, we describe an automatic design framework based on an in-house designed La FREMD Fingerprint and machine learning (ML) algorithms for highly efficient OPV donor molecules. The key building blocks are identified, and a library consisting of 18 960 new molecules is generated within this framework. Through investigating the chemical structures of materials with different performance, a guidance on designing efficient OPV materials is proposed. Furthermore, the most promising candidates exhibit a predicted power conversion efficiency (PCE) value of over 15% when combined with acceptor Y6. Density functional theory (DFT) studies show these candidate materials possess exceptional potential for efficient charge carrier transport. The proposed framework demonstrates the ability to design new materials based on the substructure-property relationship built by ML, which provides an alternative methodology for applying ML in new material discovery.

7.
Artigo em Inglês | MEDLINE | ID: mdl-34501958

RESUMO

China's industry is still in the middle of industrialization. Land use activities are crucial to the growth of carbon emissions. However, few scholars focus on the influence mechanism between industrial land use efficiency (ILUE) and industrial carbon emissions. In this paper, the threshold model and the spatial Durbin model are used to investigate the spatial threshold effect of industrial land use efficiency on industrial carbon emission from 2003 to 2018. The results show that ILUE of China's provinces basically shows an improvement trend, with little difference in spatial distribution, showing a pattern of high in the eastern region and low in the western region. When economic development level (A) and technical level (T) are taken as the threshold variable, ILUE has a single threshold effect on industrial carbon emissions in the eastern region. In the central region, with a as the threshold variable, ILUE shows a double threshold effect on industrial carbon emission. Under the 0-1 geographical proximity weight matrix, the indirect spillover effect of ILUE on reducing regional carbon emissions is significant, and the indirect effect is even greater than that on regional carbon emissions. The spatial spillover effect is not significant in the eastern region. These findings have important practical significance for promoting regional industrial transformation and upgrading, optimizing land space and realizing high-quality economic development.

8.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 38(9): 907-911, 2021 Sep 10.
Artigo em Chinês | MEDLINE | ID: mdl-34487542

RESUMO

ABCC1 gene is expressed in various tissues and organs of the human body, and can transport substrates including drugs, heavy metals, toxic substances and organic anions. Previous research on ABCC1 gene has mostly focused on tumor multidrug resistance. Recently, ABCC1 has been proposed as a candidate gene for hereditary hearing impairment, which has attracted much attention. ABCC1-associated deafness may be related to its role in biological barriers. This article has summarized recent progress in the study of the role of ABCC1 in the blood-testis barrier, placental barrier, blood-brain barrier, blood-labyrinth barrier, which may provide insight into its biological functions.


Assuntos
Surdez , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Placenta , Transporte Biológico , Surdez/genética , Feminino , Humanos , Masculino , Gravidez
9.
BMC Surg ; 21(1): 337, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34488725

RESUMO

BACKGROUND: Open reduction and internal fixation (ORIF) is the preferred choice for treating clavicle fractures. The brachial plexus injury caused by ORIF of a clavicle fracture is very rare. If it is not treated in time, the function of the brachial plexus will be challenging to recover, which will eventually lead to upper limb dysfunction and seriously affect the patient's quality of life. Our team recently used ORIF to treat a patient with a clavicle fracture, who developed brachial plexus injury symptoms after surgery. CASE PRESENTATION: A 34-year-old female patient was admitted to the hospital for 13 h due to the right shoulder movement restriction after a fall. Due to the significant displacement of the fracture, we used ORIF to treat the fracture. The surgery went well. When the anaesthesia effect subsided 12 h after the operation, the patient developed right brachial plexus injury symptoms, decreased right upper limb muscle strength, dysfunction, and hypoesthesia. Symptomatic treatments, such as nourishing nerve and electrical stimulation, were given immediately. Sixty days after the operation, the patient's brachial plexus injury symptoms disappeared, and the function of the right upper limb returned to the preoperative state. CONCLUSIONS: Patients with clavicle fractures usually need to undergo a careful physical examination before surgery to determine whether symptoms of brachial plexus injury have occurred. Anaesthesia puncture requires ultrasound guidance to avoid direct damage to the brachial plexus. When the fracture end is sharp, reset should be careful to prevent nerve stump stabbed. When using an electric drill to drill holes, a depth limiter should be installed in advance to prevent the drill from damaging the subclavian nerve and blood vessels. When measuring the screw depth, the measuring instrument should be close to the bone surface and sink slowly to avoid intense hooks and damage to the brachial plexus. Try to avoid unipolar electrosurgical units to prevent heat conduction from damaging nerves, and bipolar electrocoagulation should be used instead. If symptoms of brachial plexus injury occur after surgery, initial symptomatic treatment is drugs and functional exercise, and if necessary, perform surgical exploration.


Assuntos
Plexo Braquial , Fraturas Ósseas , Procedimentos Cirúrgicos Reconstrutivos , Adulto , Clavícula/cirurgia , Feminino , Fraturas Ósseas/cirurgia , Humanos , Qualidade de Vida
10.
Dis Markers ; 2021: 9965343, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34497677

RESUMO

Background: The role of IgG subclass in idiopathic membranous nephropathy (IMN) was unclarified. Recent study found IgG subtype switches from IgG1 to IgG4 in the early pathological stage in IMN. The profile of IgG subclass in phospholipase A2 receptor- (PLA2R-) related and PLA2R-unrelated IMN was unrevealed. Our study is aimed at testifying whether IgG subclass switch existed in PLA2R-related and PLA2R-unrelated IMN, respectively. Methods: Our study retrospectively enrolled 157 Chinese patients with biopsy-confirmed IMN between September 2017 and November 2019. We measured glomerular PLA2R antigen and serum anti-PLA2R antibody to classify the patients into PLA2R-related (n = 132) and PLA2R-unrelated (n = 25) subgroup. We evaluated glomerular IgG subclass by immunofluorescence (IF) predominance. Our study defined IgG subclass deposition as predominant if the IF score was higher than the other three and ≥1 +, or as codominant if the IF intensity was equal to any other and ≥1 +. We explored the relationship between IF predominance of glomerular IgG subtype and electron microscopic (EM) stages of IMN. Results: We did not find statistical difference of predominant or codominant rate (pre/co-rate) among EM stages in any subclass (P > 0.05). Pre/co-rate of IgG3 linearly associated with EM stage in total and PLA2R-related subgroup (P = 0.044, P = 0.013). PLA2R-related subgroup showed higher IgG4 intensity (2.1 ± 0.6 vs. 1.6 ± 0.7, P = 0.001) and pre/co-rate of IgG4 in stage 1 (97% vs. 57%, P = 0.015) than PLA2R-unrelated group. We found no difference of IgG subclass pre/co-rate in different EM stages or linear association between pre/co-rate of IgG1, IgG2, IgG4, and EM stages (P > 0.05). Conclusions: Pre/co-rate of IgG3 declined with EM stage in total and PLA2R-related subgroup. We did not find IgG subclass switches from IgG1 to IgG4 in either IMN patients or subgroups.

11.
J Hazard Mater ; 416: 126120, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492915

RESUMO

Evidence is limited regarding the acute effects of personal fine particulate matter (PM2.5) exposure and its respiratory tract depositions on the alteration of children's blood pressure (BP). We conducted 2 longitudinal panel studies in 2 cities to evaluate the relations of 72-h real-time personal PM2.5 exposure and its depositions in 3 respiratory tract regions over different lag times with BP and the risk of prehypertension and hypertension among 286 children aged 4-12 years. We found the strongest effects of PM2.5 exposure on increased BP and risk of prehypertension and hypertension at lag 2 day, in dose-response manner, even when PM2.5 below Chinese Ambient Air Quality Standard (CAAQS) Grade II. Moreover, compared to PM2.5, tracheobronchial and alveolar depositions displayed more evident effects on BP outcomes. Interestingly, all above relationships were stronger among children in Guangzhou with lower PM2.5 and its deposited doses than those in Weinan. Additionally, boys and those with daily extra-school activity ≥ 1 h were more susceptible to PM2.5-induced BP effects with significant interactions. Our results highlighted that short-term PM2.5 exposure and its respiratory tract depositions were dose-responsive related to higher BP, prevalence of prehypertension and hypertension among children, even when PM2.5 below CAAQS II.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Poluição do Ar/análise , Pressão Sanguínea , Criança , China/epidemiologia , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Humanos , Masculino , Material Particulado/análise , Material Particulado/toxicidade , Sistema Respiratório
12.
Clin Lab ; 67(9)2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34542957

RESUMO

BACKGROUND: This study is to explore the predictive value of peripheral blood neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) on the prognosis of patients with peritoneal dialysis (PD). METHODS: A total of 378 patients who underwent PD from July 2004 to November 2019 were selected as the research subjects. According to whether death occurred during the follow-up period, they were divided into death group (86 cases) and survival group (292 cases). The differences in clinical indicators between the two groups were compared, and the multivariate Cox regression model and receiver operating characteristic curve (ROC) were used to analyze and summarize the factors affecting the prognosis of PD patients. RESULTS: Compared with the survival group, there were significant differences in age, lymphocytes, NLR, PLR, and combined cerebrovascular disease between the death group and the survival group (p < 0.05). Multivariate Cox regression analysis showed that advanced age (HR = 1.055, 95% CI: 1.038 - 1.072), increased NLR (HR = 1.136, 95% CI: 1.067 - 1.210), and increased PLR (HR = 1.184, 95% CI: 1.018 - 3.026) were risk factors for all-cause death in PD patients. The results showed that the area under the ROC curve (AUC) of NLR and PLR for predicting all-cause death of PD patients were 0.698 and 0.659, respectively, the sensitivity was 69.77%, and the specificity was 66.78% and 58.56%, respectively. The optimal critical values were NLR ≥ 3.71 and PLR ≥ 149.28. Taking the best cutoff value of the ROC curve as the threshold, it showed that the cumulative survival rate of patients with NLR ≥ 3.71 was significantly lower than that of patients with NLR < 3.71 (Log rank 2 = 37.551, p = 0.000). It also showed that the cumulative survival rate of patients with PLR ≥ 149.28 was lower than that of patients with PLR < 149.28 (Log rank 2 =23.686, p = 0.000). CONCLUSIONS: NLR and PLR have a good predictive effect on the prognosis of PD patients.

13.
BMC Oral Health ; 21(1): 457, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34544417

RESUMO

BACKGROUND: A nomogram is a tool that transforms complex regression equations into simple and visual graphs and enables clinicians and patients to conveniently compute output probabilities without needing medical knowledge and complex formulas. The aim of this study was to develop and validate a predictive nomogram to screen for severe caries among 12-year-old children based on risk factors in Sichuan Province, China. METHODS: A cross-sectional study of 4573 12-year-olds was conducted up to May 2016 in middle schools from three districts and three counties in Sichuan Province, China. All the children underwent oral examinations and completed questionnaires to assess general information, oral impacts on daily performance, dietary habits, subjective health conditions, history of dental trauma, frequency of toothache, dental visits, and knowledge, attitudes, and behaviours toward oral hygiene. Univariate analysis and multivariate logistic regression analysis were used to determine which variables were significantly associated with severe caries (operationalized as DMFT ≥ 3). A nomogram was developed and validated by using the 'rms' package and two cross-validation methods. RESULTS: Severe caries was found in 537 of the 4573 children (11.74%). Multivariate logistic regression analysis revealed that the following variables predicted a higher risk of severe caries: 'female' [odds ratio (OR) = 1.985, 95% confidence interval (95% CI): 1.63-2.411], 'urban' (OR = 2.389, 95% CI: 1.96-2.91), 'non-only child' (OR = 1.317, 95% CI: 1.07-1.625), 'very poor self-assessment of oral health status' (OR = 2.157, 95% CI: 1.34-3.467) and 'visited a dentist less than 6 months' (OR = 1.861, 95% CI: 1.38-2.505). Multivariate logistic regression analysis also indicated that the following variables predicted a lower risk of severe caries: 'middle level of urbanization' (OR = 0.395, 95% CI: 0.32-0.495) and 'high level of urbanization' (OR = 0.466, 95% CI: 0.37-0.596). Both the fivefold and leave-one-out cross-validation methods indicated that the nomogram model built by these 6 variables displayed good disease recognition ability. CONCLUSIONS: The nomogram was a simple-to-use model to screen children for severe caries. This model was found to facilitate non-dental professionals in assessing risk values without oral examinations and making referrals to dental professionals.

14.
Eur Heart J ; 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34506618

RESUMO

AIMS : This study aimed to assess the clinical characteristics and long-term survival outcome in patients with Takayasu's arteritis-associated pulmonary hypertension (TA-PH). METHODS AND RESULTS: We conducted a nationally representative cohort study of TA-PH using data from the National Rare Diseases Registry System of China. Patients with pulmonary artery involvement who fulfilled the diagnostic criteria of Takayasu's arteritis and pulmonary hypertension were included. The primary outcome was the time from diagnosis of TA-PH to the occurrence of all-cause death. Between January 2007 and January 2019, a total of 140 patients were included, with a mean age of 41.4 years at diagnosis, and a female predominance (81%). Patients with TA-PH had severely haemodynamic and functional impairments at diagnosis. Significant improvements have been found in N-terminal pro-B-type natriuretic peptide (NT-proBNP) and haemodynamic profiles in patients with TA-PH receiving drugs approved for pulmonary arterial hypertension. The overall 1-, 3-, and 5-year survival rates in TA-PH were 94.0%, 83.2%, and 77.2%, respectively. Predictors associated with an increased risk of all-cause death were syncope [adjusted hazard ratio (HR) 5.38 (95% confidence interval 1.77-16.34), P = 0.003], NT-proBNP level [adjusted HR 1.04 (1.03-1.06), P < 0.001], and mean right atrial pressure [adjusted HR 1.07 (1.01-1.13), P = 0.015]. CONCLUSION : Patients with TA-PH were predominantly female and had severely compromised haemodynamics. More than 80% of patients in our cohort survived for at least 3 years. Medical treatment was based on investigators' personal opinions, and no clear risk-to-benefit ratio can be derived from the presented data.

16.
J Immunother Cancer ; 9(9)2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34489334

RESUMO

BACKGROUND: A better understanding of the molecular mechanisms that manifest in the immunosuppressive tumor microenvironment (TME) is crucial for developing more efficacious immunotherapies for hepatocellular carcinoma (HCC), which has a poor response to current immunotherapies. Regulatory T (Treg) cells are key mediators of HCC-associated immunosuppression. We investigated the selective mechanism exploited by HCC that lead to Treg cells expansion and to find more efficacious immunotherapies. METHODS: We used matched tumor tissues and blood samples from 150 patients with HCC to identify key factors of Treg cells expansion. We used mass cytometry (CyTOF) and orthotopic cancer mouse models to analyze overall immunological changes after growth differentiation factor 15 (GDF15) gene ablation in HCC. We used flow cytometry, coimmunoprecipitation, RNA sequencing, mass spectrum, chromatin immunoprecipitation and Gdf15 -/-, OT-I and GFP transgenic mice to demonstrate the effects of GDF15 on Treg cells and related molecular mechanism. We used hybridoma technology to generate monoclonal antibody to block GDF15 and evaluate its effects on HCC-associated immunosuppression. RESULTS: GDF15 is positively associated with the elevation of Treg cell frequencies in patients wih HCC. Gene ablation of GDF15 in HCC can convert an immunosuppressive TME to an inflammatory state. GDF15 promotes the generation of peripherally derived inducible Treg (iTreg) cells and enhances the suppressive function of natural Treg (nTreg) cells by interacting with a previously unrecognized receptor CD48 on T cells and thus downregulates STUB1, an E3 ligase that mediates forkhead box P3 (FOXP3) protein degradation. GDF15 neutralizing antibody effectively eradicates HCC and augments the antitumor immunity in mouse. CONCLUSIONS: Our results reveal the generation and function enhancement of Treg cells induced by GDF15 is a new mechanism for HCC-related immunosuppression. CD48 is the first discovered receptor of GDF15 in the immune system which provide the possibility to solve the molecular mechanism of the immunomodulatory function of GDF15. The therapeutic GDF15 blockade achieves HCC clearance without obvious adverse events.

17.
Nat Commun ; 12(1): 5281, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34489402

RESUMO

The archaeal phylum Woesearchaeota, within the DPANN superphylum, includes phylogenetically diverse microorganisms that inhabit various environments. Their biology is poorly understood due to the lack of cultured isolates. Here, we analyze datasets of Woesearchaeota 16S rRNA gene sequences and metagenome-assembled genomes to infer global distribution patterns, ecological preferences and metabolic capabilities. Phylogenomic analyses indicate that the phylum can be classified into ten subgroups, termed A-J. While a symbiotic lifestyle is predicted for most, some members of subgroup J might be host-independent. The genomes of several Woesearchaeota, including subgroup J, encode putative [FeFe] hydrogenases (known to be important for fermentation in other organisms), suggesting that these archaea might be anaerobic fermentative heterotrophs.

18.
Artigo em Inglês | MEDLINE | ID: mdl-34490710

RESUMO

A strategy of chiral donor-acceptor copolymerization is proposed to develop chiral nonconjugated polymers with thermally activated delayed fluorescence (TADF). Based on this strategy, two pairs of chiral polymers ( R , R )-/( S , S )- pTpAcDPS and ( R , R )-/( S , S )- pTpAcBP were synthesized. The alternating copolymerization of the chiral donors and acceptors could effectively separate the frontier molecular orbitals, which made the polymers show small Δ E ST of 0.01-0.03 eV and efficient TADF properties. Moreover, the polymers also showed the quantum yield of up to 92% and the circularly polarized luminescence. The solution-processed circularly polarized organic light-emitting diodes showed circularly polarized electroluminescence signals with high external quantum efficiencies of up to 22.1% and maximum luminance of up to 34350 cd m -2 . This is the first report of CP-OLEDs based on chiral TADF polymer, which provides a useful and valuable guidance for the development of high-efficiency CPEL polymers.

19.
Dev Cell ; 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34473941

RESUMO

Ultraviolet (UV) radiation is a prime environmental stressor that our epidermis is exposed to on a daily basis. To avert UV-induced damage, epidermal stem cells (EpSCs) become pigmented via a process of heterotypic interaction between melanocytes and EpSCs; however, the molecular mechanisms of this interaction are not well understood. In this study, we show that the function of a key chromatin regulator, the Polycomb complex, was reduced upon UV exposure in human and mouse epidermis. Genetic ablation of key Polycomb subunits in murine EpSCs, mimicking depletion upon UV exposure, results in an increased number of epidermal melanocytes and subsequent epidermal pigmentation. Genome-wide transcriptional and chromatin studies show that Polycomb regulates the expression of UV-responsive genes and identifies type II collagen (COL2A1) as a critical secreted regulator of melanogenesis and epidermal pigmentation. Together, our findings show how UV exposure induces Polycomb-mediated changes in EpSCs to affect melanocyte behavior and promote epidermal pigmentation.

20.
Transplant Cell Ther ; 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34474166

RESUMO

INTRODUCTION: Each year more than 8,000 allogeneic stem cell transplantations (allo-SCT) are performed in the United States and approximately 30% of these patients are ≥60 years old. Allo-SCT cases have increased risk to develop human papillomavirus (HPV)-related precancer or second malignancy. It is important to evaluate HPV-related precancer or second malignancy among allo-SCT cases to develop or enhance screening and preventive practice guidelines to improve patients' survival and quality of life. OBJECTIVE: We estimated the cumulative incidence of HPV-related precancer or second malignancy in both male and female Medicare beneficiaries who received allo-SCT and compared it with non-SCT controls and non-cancer controls. MATERIALS AND METHODS: This is a retrospective matched case control study. Hematologic cancer patients aged ≥18 years who received allo-SCT between 2002 and 2011 were matched 1:5 to non-SCT controls and to non-cancer controls by age, sex, race/ethnicity, and follow-up time. Proportions of HPV-related precancer or second malignancy were estimated and compared between cases and controls using Chi-square test and logistic regression. Kaplan-Meier cumulative incidences were estimated and compared using log rank tests. RESULTS: We identified 700 allo-SCT cases (median age of 64 years and median follow-up time post-transplant of 4.3 years) matched with 3159 non-SCT controls and 3302 non-cancer controls. About 3.7% of allo-SCT cases developed HPV-related precancer or second malignancy post-transplant, compared with 1.9% in the non-SCT controls and 1.1% in the non-cancer controls. The odds ratio of developing HPV-related precancer or second malignancy of allo-SCT cases compared with non-SCT controls and non-cancer controls was 2.0 (95% confidence interval [CI]: 1.25-3.18) and 3.5 (95% CI: 2.1-5.8), respectively. Both allo-SCT cases and non-SCT controls had significantly higher proportions and odds in developing HPV-related precancer or second malignancy than non-cancer controls. The 5-year cumulative incidence in allo-SCT cases was 5% compared with 2.1% in non-SCT controls and 1.2% in non-cancer controls. The cumulative incidence of HPV-related precancer or second malignancy in the allo-SCT was statistically significantly higher than either of the two matched control groups, and non-SCT controls had a higher cumulative incidence of HPV-related precancer or second malignancy than that in non-cancer controls. DISCUSSION: Allo-SCT cases were at increased risk of developing HPV-related precancer or second malignancy compared with non-SCT controls and non-cancer controls. Routine screening of HPV-related precancer or second malignancy in allo-SCT cases is needed to prevent HPV-related precancer or second malignancy.

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