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1.
Oncol Rep ; 45(3): 1306-1314, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33650669

RESUMO

Non­small cell lung cancer (NSCLC) remains an intractable disease, which is primarily due to tumor metastasis and the acquisition of resistance to chemotherapy. Therefore, there is an urgent need for novel therapeutics to overcome these obstacles. It was recently demonstrated that upregulated expression of monoamine oxidase A (MAOA) contributes to the progression of NSCLC. G10, a tumor­targeting representative conjugate of heptamethine carbocyanine dye and an inhibitor of MAOA, was shown to exert potent cytotoxic effects, comparable to those of doxorubicin, against prostate cancer cell lines, as well as moderate MAOA inhibitory activity. The research described herein aimed to extend our previous study on the antitumor function of G10 in NSCLC in vitro and in vivo, and to elucidate the mechanisms through which G10 exerts its antineoplastic effects. G10 markedly inhibited the proliferation of paclitaxel­resistant NSCLC cells (H460/PTX) and reduced tumor cell migration and invasion. Gene expression profiling of paclitaxel­resistant NSCLC cells following treatment with G10 demonstrated that the expression of genes associated with the extracellular matrix was significantly affected, particularly the metastasis­related genes matrix metallopeptidase (MMP)2, MMP14 and COL6A, which exhibited notably reduced expression. Additionally, the results also demonstrated that MAOA­related pathways, including AKT and hypoxia­inducible factor­1α, were also inhibited by G10 treatment and, subsequently, the downstream molecules of these pathways, such as p21, MMP2 and vascular endothelial growth factor, were also downregulated, highlighting a possible mechanism through which G10 suppresses tumor cell migration, invasion and proliferation. Importantly, in mouse NSCLC xenografts, combined treatment with G10 and paclitaxel resulted in pronounced inhibition of tumor growth. Taken together, the results of the present study highlight the potential of G10 as a novel therapeutic targeting MAOA in paclitaxel­resistant NSCLC.

2.
Inorg Chem ; 2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33729790

RESUMO

Herein, we report a dia-type metal-organic hybrid network based on the [Ag4Br6] clusters and hexamethylenetetramine molecules wherein both the inorganic nodes and organic linkers feature adamantane-like geometry with a Td symmetry. The silver bromine complex presents a dual emission and exhibits an interesting luminescent thermochromism behavior. Remarkably, white-light emission can be readily realized through variation of the temperature. In addition, the title compound is expected to be competent as a luminescent thermometer for temperature identification.

3.
FEMS Microbiol Lett ; 368(5)2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33606020

RESUMO

In recent years, the relationship between type 2 diabetes (T2D) and gut microbiota has attracted much interest. Dendrobium officinale is a valuable traditional Chinese medicine (TCM) with anti-T2D potential, while its action mechanism remains to be further studied. This study was designed to investigate the modulation effects of D. officinale on gut microbiota of T2D model mice to provide clues to its pharmacology by high-throughput sequencing techniques. It was found that D. officinale supplement could significantly reduce the fasting blood glucose levels of T2D mice. Dendrobium officinale supplement could modulate the composition of gut microbiota and increase the relative abundances of key bacterial taxa associated with T2D development, including Akkermansia and Parabacteroides. Compared with placebo group mice, several Kyoto Encyclopedia of Gene and Genomes pathways associated with T2D altered in the D. officinale treated group. These findings indicated the modulation of D. officinale on gut microbiota of T2D mice, which provide potential pharmacological implications.

4.
BMC Cancer ; 21(1): 59, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33435902

RESUMO

BACKGROUND: The prognosis of childhood acute lymphoblastic leukemia (ALL) is optimistic with a 5-year event-free survival (EFS) rate of 70-85%. However, the major causes of mortality are chemotherapy toxicity, infection and relapse. The Guangdong (GD)-2008-ALL collaborative protocol was carried out to study the effect of reduced intensity on treatment related mortality (TRM) based on Berlin-Frankfurt-Münster (BFM) 2002 backbone treatment. The study was designed to elucidate whether the reduced intensity is effective and safe for children with ALL. METHODS: The clinical data were obtained from February 28, 2008 to June 30, 2016. A total of 1765 childhood ALL cases from 9 medical centers were collected and data were retrospectively analyzed. Patients were stratified into 3 groups according to bone marrow morphology, prednisone response, age, genotype, and karyotype information: standard risk (SR), intermediate risk (IR) and high risk (HR). For SR group, daunorubicin was decreased in induction IA while duration was reduced in Induction Ib (2 weeks in place of 4 weeks). Doses for CAM were same in all risk groups - SR patients received one CAM, others got two CAMs. RESULTS: The 5-year and 8-year overall survival (OS), event-free survival (EFS) and cumulative incidence of relapse (CIR) were 83.5±0.9% and 83.1±1.0%, 71.9±1.1% and 70.9±1.2%, and 19.5±1.0% and 20.5±1.1%, respectively. The 2-year treatment-related mortality (TRM) was 5.2±0.5%. The 5-year and 8-year OS were 90.7±1.4% and 89.6±1.6% in the SR group, while the 5-year and 8-year EFS were 81.5±1.8% and 80.0±2.0%. In the SR group, 74 (15.2%) patients measured minimal residual disease (MRD) on Day 15 and Day 33 of induction therapy. Among them, 7 patients (9.46%) were MRD positive (≥ 0.01%) on Day 33. The incidence of relapse in the MRD Day 33 positive group (n=7) was 28.6%, while in the MRD Day 33 negative group (n=67) was 7.5% (p=0.129). CONCLUSIONS: The results of GD-2008-ALL protocol are outstanding for reducing TRM in childhood ALL in China with excellent long term EFS. This protocol provided the evidence for further reducing intensity of induction therapy in the SR group according to the risk stratification. MRD levels on Day 15 and Day 33 are appropriate indexes for stratification.

5.
Inorg Chem ; 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33504152

RESUMO

By mediation of the pH values, three novel inorganic-organic iodoplumbate hybrids, [Me3TPT][Pb3I9] [1; Me3TPT = trimethyl-2,4,6-tris(4-pyridyl)-1,3,5-triazine], [Me3TPT]2[Pb9I24] (2), and [Me3TPT]2[Pb19I44] (3), have been achieved under solvothermal conditions. The large conjugated in situ N-alkylation polypyridine derivatives act as structure-directing agents and electron acceptors, making the materials feature adjustable structural variations with 0D, 1D, and 2D structures and a potential semiconductive performance with narrow energy gaps (1.72, 1.80, and 1.78 eV for 1-3, respectively), which result in their efficient photocatalytic activity under visible-light irradiation. Theoretical calculation reveals that the conjugated organic moieties greatly contribute to the conduction band, leading to narrow band gaps. It is expected that the work will contribute to the exploitation of novel semiconducting halometallates by employing conjugated organic species as structure-directing agents.

6.
Appl Microbiol Biotechnol ; 105(3): 1007-1015, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33449129

RESUMO

Transition metal ions are essential micronutrients for all living organisms and exert a wide range of effects on human health. The uptake of transition metal ions occurs primarily in the gastrointestinal tract, which is colonized by trillions of bacterial cells. In recent years, increasing studies have indicated that transition metals have regulatory effects on the gut microbiota. In view of the significant effect of the gut microbiota on human health and involvement in the pathogenesis of a wide range of diseases, in this paper, we provide a comprehensive discussion on the regulatory effects of four kinds of transition metal ions on the gut microbiota. A total of 20 animal model and human studies concerning the regulatory effects of four types of transition metal ions (i.e., iron, copper, zinc, and manganese) on gut microbiota were summarized. Both the deficiency and supplementation of these transition metal ions on the gut microbiota were considered. Furthermore, the potential mechanisms governing the regulatory effects of transition metal ions on the gut microbiota were also discussed. KEY POINTS : • Regulatory effects of iron, copper, zinc, and manganese on gut microbiota were reviewed. • Both deficiency and supplementation of metal ions on gut microbiota were considered. • Mechanisms governing effects of metal ions on gut microbiota were discussed.

7.
Mol Med Rep ; 23(2): 1, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33355379

RESUMO

Renal damage is a common and severe condition encountered in the clinic. Luteolin (Lut) exhibits anti­inflammatory, anti­fibrotic and anti­apoptotic effects. Thus, the present study aimed to investigate the pharmacological effects of Lut on angiotensin II (AngII)­induced renal damage in apolipoprotein E­deficient (ApoE­/­) mice. Male ApoE­/­ mice (age, 8 weeks) were randomly divided into the following three groups: i) Control group (n=6); ii) AngII group (n=6); and iii) AngII + Lut group (n=6). Lut was administered by gavage (100 mg/kg/d). ApoE­/­ mice were implanted with Alzet osmotic minipumps, filled with either saline vehicle or AngII solution for a maximum period of 4 weeks. After 4 weeks, metabolic characteristics were measured and the histopathological alterations in the kidney tissue were observed. The metabolic characteristics of blood creatinine (CRE) levels were lower in the AngII + Lut group compared with in the AngII group. The expression levels of collagen I and III were lower in the kidney tissues of the AngII + Lut group compared with the corresponding tissues of the AngII group. The gene expression levels of IL­1ß, IL­6, TNF­α and IL­10 were also suppressed in the kidney tissues of the AngII + Lut group compared with those in the corresponding tissues of the AngII group. Furthermore, the AngII + Lut group exhibited markedly increased LC3 protein expression and notably decreased p62 protein expression in the kidney tissues compared with the expression levels in the AngII group. The data demonstrated that Lut attenuated AngII­induced collagen deposition and inflammation, while inducing autophagy. Collectively, the results suggested that Lut treatment exhibited a exerted effect on AngII­induced renal injury in ApoE­/­ mice.

8.
Hematology ; 26(1): 31-36, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33357172

RESUMO

OBJECTIVES: Our aim is to evaluate initial efficacy, safety, and durable response of eltrombopag in the treatment of Chinese children with chronic immune thrombocytopenia (cITP). METHODS: This was a retrospective, single-center cohort study including 30 pediatric patients with cITP administered eltrombopag between 1 July 2017 and 1 January 2019. Patients with at least 12 weeks of eltrombopag treatment and available follow-up data were included. Initial response rate, durable response rate, bleeding events, and adverse events were assessed during the follow-up period. RESULTS: The median duration of eltrombopag administration was 6 months (range 3-8 months). The initial response rate was 73.3%. Patients with megakaryocyte count ≥100/slide or Treg <4.5% were more likely to achieve initial response. The median follow-up period was 10 months (range 6-20 months). A total of 53.2% of pediatric patients had a durable response of up to 20 months. Patients with megakaryocyte count ≥100/slide and Treg<4.5% had more than 60% durable response rates compared with individuals with megakaryocyte count<100/slide and Treg≥4.5%, respectively. No serious bleeding events or serious adverse events occurred during the study period. CONCLUSION: Eltrombopag not only shows excellent initial response but also has continued efficacy and safety. Patients with megakaryocyte count ≥100/slide and Treg<4.5% achieve increased initial response and more frequent durable response.

9.
Br J Pharmacol ; 178(5): 1133-1148, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33347603

RESUMO

BACKGROUND AND PURPOSE: Cancer cells exhibit more dependence on iron and enhanced sensitivity to iron-dependent, programmed cell death (ferroptosis) than normal cells. Quercetin exerts anti-cancer effects, but the underlying molecular mechanism is largely unknown. In this study, we aimed to investigate the involvement of lysosome function and ferroptosis in the anti-cancer potential of quercetin. EXPERIMENTAL APPROACH: We used MTT assays and DNA content analysis to evaluate the cytotoxicity, colony formation assay to investigate cell proliferation, and flow cytometry and confocal microscopy to detect lysosomal acidification and protease enzyme activity. Western blotting, cell subfractionation, RT-PCR and siRNA transfection were used to establish molecular mechanisms of action. KEY RESULTS: Quercetin is known to promote p53-independent cell death in various cancer cell lines. Although quercetin induces autophagy, genetic silencing of Atg7 fails to affect quercetin-induced cell death. In contrast, both lysosome inhibitors and knockdown of the transcription factor EB can prevent quercetin-induced cell death, suggesting the involvement of lysosome. Next, quercetin is found to induce lysosomal activation sequentially through nuclear translocation of EB and transcriptional activation of lysosomal genes. Notably, quercetin promoted lysosome-dependent ferritin degradation and free iron release. This action and quercetin-induced ROS generation synergistically resulted in lipid peroxidation and ferroptosis. Furthermore, Bid may link ferroptosis with apoptosis to cause cell death. CONCLUSION AND IMPLICATIONS: Quercetin induced EB-mediated lysosome activation and increased ferritin degradation leading to ferroptosis and Bid-involved apoptosis. Results from this study may expand our current knowledge about the mechanism of quercetin as an anti-cancer agent.

10.
Acta Pharmacol Sin ; 2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33154555

RESUMO

Hydrogen sulfide (H2S), which is closely related to various cardiovascular disorders, lowers blood pressure (BP), but whether this action is mediated via the modification of baroreflex afferent function has not been elucidated. Therefore, the current study aimed to investigate the role of the baroreflex afferent pathway in H2S-mediated autonomic control of BP regulation. The results showed that baroreflex sensitivity (BRS) was increased by acute intravenous NaHS (a H2S donor) administration to renovascular hypertensive (RVH) and control rats. Molecular expression data also showed that the expression levels of critical enzymes related to H2S were aberrantly downregulated in the nodose ganglion (NG) and nucleus tractus solitarius (NTS) in RVH rats. A clear reduction in BP by the microinjection of NaHS or L-cysteine into the NG was confirmed in both RVH and control rats, and a less dramatic effect was observed in model rats. Furthermore, the beneficial effects of NaHS administered by chronic intraperitoneal infusion on dysregulated systolic blood pressure (SBP), cardiac parameters, and BRS were verified in RVH rats. Moreover, the increase in BRS was attributed to activation and upregulation of the ATP-sensitive potassium (KATP) channels Kir6.2 and SUR1, which are functionally expressed in the NG and NTS. In summary, H2S plays a crucial role in the autonomic control of BP regulation by improving baroreflex afferent function due at least in part to increased KATP channel expression in the baroreflex afferent pathway under physiological and hypertensive conditions.

11.
Pediatr Transplant ; 24(8): e13876, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33098346

RESUMO

BACKGROUND: Early-onset mixed chimerism (MC) with a high proportion of residual host cells is considered a signal of graft rejection in patients undergoing allogenic hematopoietic stem cell transplantation for transfusion-dependent thalassemia. In order to prevent graft rejection and minimize the risk of treatment-related graft-versus-host disease (GVHD), we established a hierarchical management system based on chimerism analysis. METHOD: This retrospective study provides a comprehensive review of the characteristics, interventions, and outcomes of the 38 patients who developed MC after transplantation among the 144 pediatric thalassemia patients between July 2007 and January 2019 at our center. RESULTS: A sibling donor, a blood type-matched donor, conditioning regimens without fludarabine, and transplants containing <10 × 108 total nucleated cells/kg were identified to be associated with the development of MC. Among the 38 patients developing MC, only four patients rejected the grafts. The response rate to donor lymphocyte infusion (DLI, only for patients receiving sibling donor transplantation) and cytokine immunomodulation without DLI was 70.6% and 42.9%, respectively. Patients that developed GVHD after DLI or cytokine therapy had a more significant increase in donor cell chimerism (16%, range 0%-35%) than those without (8.5%, range -21% to 40%, P = .049). However, even when treatment-related GVHD was included, patients with MC had a lower cumulative incidence of total acute GVHD than patients with complete donor chimerism (29.2% vs 48.0%, P = .030). CONCLUSIONS: Interventions based on chimerism analysis were effective in preventing graft rejection and did not increase treatment-related GVHD in thalassemia patients with MC.

12.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(5): 1679-1682, 2020 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-33067973

RESUMO

OBJECTIVE: To investigate the values of mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), red cell osmotic fragility test(ROFT) and hemoglobin A2(HbA2) in screening of α-thalassemia in Guangdong area. METHODS: A total of 285 peripheral blood samples in patients treated in our hospital from January 2017 to December 2017 were collected. The detection of thalassemia gene was used as the gold standard, while blood routine examination, hemoglobin electrophoresis, and red cell osmotic fragility test were simultaneously performed. The optimal cut-off values in MCV, MCH, ROFT and HbA2 in α-thalassemia were determined by receiver operator characteristic curve (ROC curve). RESULTS: The most common types of α-thalassemia gene was --SEA/αα (54.59%). Compared with the control group, the differences in MCV, MCH, ROFT and HbA2 showed statistically significantce between different types of α-thalassemia (P<0.05). The best cut-off values of MCV, MCH, ROFT, and HbA2 in the diagnosis of α-thalassemia were 81.45 fl, 27.35 pg, 79.95%, and 2.55% respectively. CONCLUSION: For different laboratories, the cut-off values need to be established for screening α-thalassemia suitable in their own local region.The values of MCV, MCH, ROFT and HbA2 shows higher accuracy and sensitivity in the diagnosis of α-thalassemia. It is recommended to use MCV<81.45fl, MCH<27.35 pg, ROFT<79.95% and HbA2<2.55% as the standards for screening α-thalassemia in Guangdong area.


Assuntos
Índices de Eritrócitos , Talassemia alfa , Hemoglobina A2/análise , Humanos , Programas de Rastreamento , Sensibilidade e Especificidade , Talassemia alfa/diagnóstico , Talassemia alfa/genética
13.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(5): 1710-1717, 2020 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-33067979

RESUMO

AbstractObjective: To investigate the effect of ALAS2 downregulation on the expression of BNIP3L and erythroid differentiation in K562 cells. METHODS: The expression of ALAS2 was down-regulated by transfection of lentivirus, then quantitative real-time PCR was performed to detect the transfection efficiency. Flow cytometry analysis was applied to evaluate apoptosis of cells, erythroid differentiation, mitochondrial membrane potential and reactive oxygen species (ROS) level. Western blot was used to detect the BNIP3L expression, Co-immunoprecipitation was performed to analyze the relationship between ALAS2 and BNIP3L. RESULTS: Compared with sh-NC group, knockdown of ALAS2 induced downregulation of BNIP3L mRNA and protein expression(P<0.01) and erythroid related transcription factors GATA1, Nrf2 expression, as well as reduction of ROS level(P<0.05). Mitochondrial membrane potential of control (sh-NC) group was lower than that of shALAS2 group(P<0.05), but there was no significant change of cell apoptotic rate in two groups. CD71highCD235ahigh + CD71lowCD235ahigh cells of sh-NC and shALAS2 groups were 53.5%, 92.9% at 96 h after hemin induction, respectively. No direct action between ALAS2 and BNIP3L was observed. CONCLUSION: The intracellular heme level can affect the expression of BNIP3L which may be related with the regulation of ROS and transcription factors GATA1 and Nrf2. Higher BNIP3L facilitates cell differentiation but lower BNIP3L is favorable for cells survival.


Assuntos
Proteínas de Transporte , Mitofagia , 5-Aminolevulinato Sintetase/metabolismo , Apoptose , Diferenciação Celular , Humanos , Células K562 , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Supressoras de Tumor
14.
Plant Biol (Stuttg) ; 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33078492

RESUMO

Tall fescue (Festuca arundinacea) is an important grass species worldwide, and the temperature stresses severely affect its distribution and yield. Transcription factors (TFs) as the master switches in sophisticated regulatory networks play essential roles in plant growth development and abiotic stress responses. In this study, we identified 877 TF genes belonging to 35 families in tall fescue under heat stress (40 ℃), cold stress (-10 ℃) and control (22 ℃) conditions. Of them, 784 differentially expressed genes were screened and classified to 33 families, such as bHLH, AP2/ERF, MYB, WRKY, NAC, bZIP, GTF, HD-ZIP, HSF etc. Among them, the expressions of bZIP and GTF family members were up-regulated mainly exposed to both heat and cold, but conversely the most members of WRKY and NAC families were reduced. Upon heat, HSF, GTE families and DREB2Bs were mainly up-regulated. Otherwise, bHLH, MYB, HD-ZIP and ERF families holistically were elevated under cold stress. Function richment analysis indicated that the TFs were involved in the pathways of "Plant hormone signal transduction", "Plant-pathogen interaction", "Circadian rhythm", etc. It showed these pathways were relevant to responding temperature stress. In the main, the temperature threats up-regulated the expressions of the stress tolerance-related genes, whereas down-regulated those genes associated with growth and disease resistance. The results exhibited that the expressions of a slew of TF genes were significantly altered by heat and cold stresses, and different TF families have commonalities and differences in response to the threats, indicating that TFs exert the crucial roles in plant adaption to adverse environment. This study profiled the response pattern of TFs to heat and cold conditions, partially explained the adaptation mechanism of cold-season forages to temperature stress, and screened plenty of candidate stress-tolerant TF genes.

15.
Artigo em Inglês | MEDLINE | ID: mdl-32951166

RESUMO

Soil contamination caused by long-term application of metsulfuron-methyl and tribenuron-methyl has become an issue of increasing concern. In our previous study, strain Chenggangzhangella methanolivorans CHL1, capable of efficiently degrading sulfonylurea herbicides, was isolated. Here, the bioremediation potential of strain CHL1 was assessed for soil polluted with metsulfuron-methyl or tribenuron-methyl in a pot experiment. The growth parameters of waxy maize were measured on day 21 of the pot experiment. Additionally, the residues of metsulfuron-methyl and tribenuron-methyl in soils were analyzed, and the soil microbial community was investigated using a phospholipid fatty acids (PLFAs) method on days 1, 7, 14, and 21. The results indicated that strain CHL1 greatly accelerated the degradation of metsulfuron-methyl and tribenuron-methyl in soils. The degradation rates in the treatments inoculated with strain CHL1were all more than 91% after 7 days, significantly higher than the 25-36% degradation measured in non-inoculated treatments. Furthermore, strain CHL1 reduced the negative effects of tribenuron-methyl and metsulfuron-methyl on waxy maize growth, especially the primary root length. Moreover, inoculation with strain CHL1 also reduced the effects of tribenuron-methyl and metsulfuron-methyl on soil microbial biomass, diversity, and community structure. The present study demonstrates that strain CHL1 has great potential application to remediate soil contaminated with metsulfuron-methyl or tribenuron-methyl.

16.
Respir Care ; 2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-32962995

RESUMO

BACKGROUND: Improving FIO2 and reducing CO2 rebreathing (V ICO2 ) are the key means to improve the therapeutic efficacy of noninvasive ventilation (NIV). This study aimed to investigate the impact of interface design on FIO2 and V ICO2 during NIV. METHODS: A simulated lung model was established to analyze 17 different interfaces. CO2 was injected into the outlet of the simulated lung, and the noninvasive ventilator was connected to the simulated lung to simulate the application of NIV in patients with COPD with hypercapnia. FIO2 and V ICO2 were calculated by mathematical integration of synchronously collected data pertaining to real-time pressure, flow, oxygen concentration, and CO2 concentration in the breathing circuit. Comparisons were performed between different types (nasal vs oronasal) and models of interfaces as well as between interfaces with different leak positions. Correlation of FIO2 and V ICO2 with inner volume and leakage, respectively, and the correlation between FIO2 and V ICO2 were analyzed. RESULTS: FIO2 levels were significantly different with a nasal or an oronasal mask (0.45 ± 0.05% vs 0.41 ± 0.08%, respectively; P < .001). FIO2 levels associated with different models of interfaces varied significantly (all P < .001); V ICO2 did not differ significantly among the different interfaces (P = .19). Leak position significantly affected FIO2 and V ICO2 (all P < .001). Both inner volume and leakage significantly correlated with FIO2 (r = -0.23, P < .001; r = -0.08, P = .02). There was a significant correlation between FIO2 and V ICO2 (r = 0.43, P < .01); the general linear equation was y = 0.17 + 0.02x (r = 0.43, R2 = 0.19). CONCLUSIONS: The design of the interface had a significant impact on FIO2 and V ICO2 during NIV. FIO2 and V ICO2 showed a significant positive correlation, although the effect size of correlation was moderate.

17.
Appl Opt ; 59(25): 7646-7651, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32902465

RESUMO

We present the design of Ge1-xSnx-on-Si waveguide photodetectors for the applications in the C- to U-bands. The GeSn photodetectors have been studied in respect to responsivity, dark current, and bandwidth, with light butt- or evanescent-coupled from an Si waveguide. With the introduction of 4.5% Sn into Ge, the GeSn waveguide PD with evanescent-coupling exhibits high responsivity of 1.25 A/W and 3 dB bandwidth of 123.1 GHz at 1.675 µm. Further increasing the Sn composition cannot improve the absorption in the U-band significantly but does lead to poorer thermal stability and higher dark current. This work suggests a promising avenue for future high-speed high-responsivity photodetection in the C- to U-bands.

18.
Sci Total Environ ; 742: 140355, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-32721713

RESUMO

Microplastics (MPs) are an emerging global pollutant. MPs research is mainly concentrated on water, with limited research on MPs in sewage sludge. MPs from various sources are collected into sewage and most of the MPs are trapped in the sludge during the sewage treatment process. Sludge is not only a sink of MPs, but also a source. Soil amendment with sludge provides nutrients into the soil, but it can also import substantial MPs into the soil, which has certain environmental risks. Therefore, we focused on the MPs in sludge and sludge-amended soil and conducted a literature review to summarize the sources, physical properties and fate of the MPs in sludge, as well as their separation, identification and statistical methods. MPs can accumulate in the soil, influence the properties of the soil, and also migrate, which might result in the pollution of deep soils and groundwater. In addition, the adsorption by MPs of heavy metals, organic pollutants, antibiotics and antibiotic resistance genes cannot be ignored as sewage sludge generally contains substantial concentrations of these pollutants. They can be adsorbed by the MPs and transferred into the soil with sludge amendment of soil. The combination and interaction of MPs with its adsorbed pollutants might increase environmental risk, further leading to possibility of them being uptaken by plants. The specific long-term risks to the environment caused by MPs in soil with sludge amendment require further exploration and investigation.


Assuntos
Metais Pesados , Poluentes do Solo/análise , Microplásticos , Plásticos , Esgotos , Solo
19.
BMC Plant Biol ; 20(1): 320, 2020 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-32635887

RESUMO

BACKGROUND: The non-coding small RNA tRFs (tRNA-derived fragments) and phasiRNAs (plant-specific) exert important roles in plant growth, development and stress resistances. However, whether the tRFs and phasiRNAs respond to the plant important stress hormone abscisic acid (ABA) remain enigma. RESULTS: Here, the RNA-sequencing was implemented to decipher the landscape of tRFs and phasiRNAs in tomato (Solanum lycopersicum) leaves and their responses when foliar spraying exogenous ABA after 24 h. In total, 733 tRFs and 137 phasiRNAs were detected. The tRFs were mainly derived from the tRNAAla transporting alanine, which tended to be cleaved at the 5'terminal guanine site and D loop uracil site to produce tRFAla with length of 20 nt. Most of phasiRNAs originated from NBS-LRR resistance genes. Expression analysis revealed that 156 tRFs and 68 phasiRNAs expressed differentially, respectively. Generally, exogenous ABA mainly inhibited the expression of tRFs and phasiRNAs. Furthermore, integrating analysis of target gene prediction and transcriptome data presented that ABA significantly downregulated the abundance of phsaiRNAs associated with biological and abiotic resistances. Correspondingly, their target genes such as AP2/ERF, WRKY and NBS-LRR, STK and RLK, were mainly up-regulated. CONCLUSIONS: Combined with the previous analysis of ABA-response miRNAs, it was speculated that ABA can improve the plant resistances to various stresses by regulating the expression and interaction of small RNAs (such as miRNAs, tRFs, phasiRNAs) and their target genes. This study enriches the plant tRFs and phasiRNAs, providing a vital basis for further investigating ABA response-tRFs and phasiRNAs and their functions in biotic and abiotic stresses.

20.
Microb Biotechnol ; 13(5): 1461-1476, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32643276

RESUMO

Given the important roles that seed-borne endophytes can play on their plant hosts, comprehensive studies of the bacterial and fungal communities of seeds are of great importance. In this study, we assessed the seed endophytes of three gramineous (Avena sativa, Elymus sibiricus and Elymus dahuricus) and four leguminous (Vicia villosa, Trifolium repens, Trifolium pretense and Medicago sativa) forages using high-throughput sequencing. In total, 1013 distinct bacterial operational taxonomic units (OTUs) and 922 fungal OTUs were detected, with bacteria and fungi per sample ranging from 240 to 425 and 261 to 463 respectively. These seven forages shared a high number of potentially beneficial taxa, including Bacillus, Pantoea, Candida and Helotiales, but the relative proportion of these taxa was different in each seed. Fungal communities were clustered more distinctively by host genotypes than bacterial. Some bacterial taxa may be involved in the recruitment of genera from the same phylum. Three Pantoea sp. and five Bacillus sp. were isolated from seeds, and all showed positive effects on Medicago sativa germination rate under salt stress, and of these, Bacillus subtilis Es-1 and Pantoea agglomerans Ed-3 performed best, but their influence was affected by the seed's microbiome. Rather than simply promoting host plant growth directly, some taxa may also participate in organizing the assembly of plant microbiomes which will influence seed response to biological factors. This study uses a new, high-throughput sequencing based strategy to identify beneficial strains and analyse the interactions between microorganisms and plants to maximize microbial functions in long-term agricultural practices.

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