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1.
Artigo em Inglês | MEDLINE | ID: mdl-32037493

RESUMO

Globally, odorant incidents are occurring at an increasing frequency, magnitude, and duration under the dual influences of eutrophication and climate change. However, the contribution of multiple ecotypes to odorant production in the complicated and dynamic lake ecosystems remains unclear. In this study, the odorants and environmental conditions in algae-dominated zones (ADZs) and macrophyte-dominated zones (MDZs) in Lake Taihu were identified and characterized. Results showed that the ADZs were characterized by an abundance of pigments and nutrients and low DO levels, while the MDZs were featured as high TOC/TN ratios and high DO levels. Most odorants in ADZs and several in MDZs exceeded the odorant threshold content. The dominant odorants were dimethyl disulfide (DMDS) and dimethyl trisulfide (DMTS), ß-ionone and ß-cyclocitral in ADZs, which were associated with the accumulation and decomposition of algal detritus. For MDZs, the dominant odorants were 2-methylisoborneol (2-MIB) and geosmin, which were at least partially attributed to the massive addition of bait in a traditional aquaculture area. In addition, the odorant concentration in the water of ADZs was approximately 3 to 21 times higher than that in MDZs, while in the benthic sediment, the odorant concentration in ADZs was approximately 2 to 3 orders of magnitude higher than in MDZs. This study highlights the production and accumulation of nuisance odorants in the benthic sediment of ADZs, indicating a risk of diffusion from the sediment to the water column. This was supported by the correlation of odorants in the water column with that in the sediment. The results of this study will be helpful for the management of different ecotypes suffering from nuisance odorants problems.

2.
Environ Pollut ; 256: 113453, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31672349

RESUMO

Eutrophic freshwater lake ecosystems are receiving increasing public attention due to a global increase in large-scale harmful cyanobacterial blooms in surface waters. However, the contribution of phytodetritus accumulation in benthic sediments post-bloom remains unclear. In this study, field investigations were performed using microsensors to evaluate benthic phytodetritus mats by measuring TOC/TN ratios, pigments, biodegradable compounds and odorants as descriptive parameters. Results show that the massive amount of phytodetritus trapped by aquatic plants gradually evolved into benthic cyanobacterial detritus mats, which were characterized as anoxic, reductive and low pH. It was confirmed that the occurrence of odorants is more serious in the detritus mats due to decay and decomposition of the accumulated phytodetritus. The mean odorant content in the vegetated zones was 3-52 times higher than that in the unvegetated zones. The dominant odorants were dimethyl trisulfide (DMTS), ß-ionone and ß-cyclocitral, with mean contents of 52.38 ng·(g·dw)-1, 162.20 ng·(g·dw)-1 and 307.51 ng·(g·dw)-1, respectively, in the sediment. In addition, odorant production appears to be associated with the distribution of biodegradable compounds in the sediment. This is supported by the marked correlation observed between biodegradable compounds and odorants. Multiple regression analysis showed that biodegradable compounds can be used as indicators to predict odorant content in the sediment. It is noteworthy that the odorant trend in the water column and sediment is symmetrical, indicating a risk of diffusion from the sediment to the water column. This study helps to clarifying the contributions of benthic cyanobacterial detritus mats to odorant production in shallow eutrophic lakes. The information provided herein may also be useful for future management of aquatic ecosystems.

3.
JAMA Oncol ; 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31876895

RESUMO

Importance: Immune checkpoint inhibitors of programmed cell death 1 (PD-1) and its ligand (PD-L1) have led to a paradigm shift in cancer treatment. Understanding the clinical efficacy and safety profile of these drugs is necessary for treatment strategy in clinical practice. Objective: To assess the differences between anti-PD-1 and anti-PD-L1 regarding efficacy and safety shown in randomized clinical trials across various tumor types. Data Sources: Systematic searches of PubMed, Cochrane CENTRAL, and Embase were conducted from January 1, 2000, to March 1, 2019. In addition, abstracts and presentations from all major conference proceedings were reviewed. Study Selection: All randomized clinical trials that compared anti-PD-1 and anti-PD-L1 with standard treatment in patients with cancer were selected as candidates. Retrospective studies, single-arm phase 1/2 studies, and trials comparing anti-PD-1 and anti-PD-L1 with other immunotherapies were excluded. Studies of anti-PD-1 and anti-PD-L1 therapy were screened and paired by the matching of clinical characteristics as mirror groups. Data Extraction and Synthesis: Three investigators independently extracted data from each study following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guideline. Trial names, first author, year of publication, study design, National Clinical Trial identifier number, blinding status, study phase, pathologic characteristics, number of patients, patients' age and sex distribution, Eastern Cooperative Oncology Group Performance Status, lines of treatment, study drugs, biomarker status, follow-up time, incidence of adverse events, and hazard ratios (HRs) with 95% CIs for overall survival and progression-free survival were extracted. A random-effects model was applied for data analysis. Main Outcomes and Measures: Differences in OS between anti-PD-1 and anti-PD-L1 across different cancer types were assessed. An effect size was derived from each mirror group and then pooled across all groups using a random-effects model. Results: Nineteen randomized clinical trials involving 11 379 patients were included in the meta-analysis. Overall, anti-PD-1 exhibited superior overall survival (HR, 0.75; 95% CI, 0.65-0.86; P < .001) and progression-free survival (HR, 0.73; 95% CI, 0.56-0.96; P = .02) compared with anti-PD-L1. No significant difference was observed in their safety profiles. Sensitivity analysis presented consistency in the overall estimates across these analyses. Consistent results were observed through frequentist and bayesian approaches with the same studies. Conclusions and Relevance: Comprehensive analysis suggests that anti-PD-1 exhibited favorable survival outcomes and a safety profile comparable to that of anti-PD-L1, which may provide a useful guide for clinicians.

4.
J Thorac Oncol ; 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31843683

RESUMO

INTRODUCTION: Blood-based tumor mutational burden (bTMB) has been studied to differentiate non-small cell lung cancer (NSCLC) patients who would benefit from anti-programmed cell death protein 1 (PD-1)/programmed death ligand 1 (PD-L1) therapies. However, it failed to predict overall survival (OS) benefits, which warrants further exploration. METHODS: Three independent cohorts of NSCLC patients treated with immunotherapy were used in this study. A new bTMB algorithm was first developed in the two independent cohorts (POPLAR, N=211 and OAK, N=462) and further validated in the third National Cancer Center cohort (NCC, N=64). RESULTS: bTMB-H (bTMB≥cut-off point) was not associated with favorable OS following immunotherapy regardless of the cut-off points in either the POPLAR and OAK or the NCC cohorts (P>0.05) due to its correlation with the circulating tumor DNA (ctDNA) amount, which was associated with poor OS. In the POPLAR and OAK cohorts, upon allele frequency (AF) adjustment, a high allele frequency bTMB (HAF-bTMB, mutation counts with an AF>5%) was strongly correlated with the ctDNA amount (Pearson's r=0.65), while a low allele frequency bTMB (LAF-bTMB, mutation counts with an AF≤5%) was not (Pearson's r=0.09). LAF-bTMB-H was associated with favorable OS (hazard ratio [[HR], 0.70; 95% confidence interval [CI], 0.52-0.95; P=0.02), progression-free survival (PFS) (HR, 0.62; 95% CI, 0.47-0.80; P<0.001), and the objective response rate (ORR) (P<0.001) following immunotherapy but not chemotherapy, with a cut-off point of 12 trained in the POPLAR cohort and validated in the OAK cohort. The LAF-bTMB algorithm was further validated in the NCC cohort in which LAF-bTMB-H was associated with OS (HR, 0.20; 95% CI, 0.05-0.84; P=0.02), PFS (HR, 0.30; 95% CI, 0.13-0.70; P=0.003), and the ORR (P=0.001). CONCLUSIONS: We developed and validated a new LAF-bTMB algorithm as a feasible predictor of OS, PFS, and the ORR following anti-PD-1/PD-L1 therapies in NSCLC patients, which needs to be prospectively validated.

5.
Huan Jing Ke Xue ; 40(12): 5367-5374, 2019 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854608

RESUMO

To reveal the distribution characteristics of carbon, nitrogen and phosphorus in the sediments of Zhushan Bay at Taihu Lake, sedimentary columns were collected and sliced by 2 cm vertically from ten sampling points in three sections of Zhushan Bay. The content of total nitrogen (TN), total phosphorus (TP), and total organic carbon (TOC) were determined for each slice to reveal their horizontal and vertical distribution. The results showed that:spatially, the content of TN, TP, and TOC increased in the surface sediments of Zhushan Bay from the open lake area to the bay, and inside the bay these indexes were significantly higher than in the open lake area (P<0.01). The content of TN, TP, and TOC in the surface sediments in the bay (section A) were 1.53 mg·g-1, 1.55 mg·g-1, and 11.31 mg·g-1, respectively, while in the surface sediments near the open lake (section C) they were only 0.75 mg·g-1, 0.57 mg·g-1, and 6.70 mg·g-1, respectively. Vertically, a feature of surficial enrichment was shown, and the contents of carbon, nitrogen and phosphorus in all three sections showed a decreasing trend with increase of depth. The contents of TN, TP and TOC in the surface sediments are 2-3 times, 2-5 times, and 2-3 times those in the bottom sediments, respectively. Generally, the average TP content in the sediment of Zhushan Bay is 0.93 mg·g-1, suggesting an apparent heavy pollution, while the average TN content is 1.11 mg·g-1 as slight pollution. According to the organic nitrogen index and comprehensive pollution index, the northern part of Zhushan Bay is suffering from heavy pollution, where the organic pollution is relatively strong. The TP pollution index is between 1.03 and 3.87, indicating heavy pollution in Zhushan Bay.

6.
Huan Jing Ke Xue ; 40(10): 4505-4512, 2019 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854818

RESUMO

In shallow eutrophic lakes, benthic bioclastic deposits accumulate abundant organic carbon derived from macrophyte detritus. Taking the typical macrophyte-dominated Xukou Bay as the study area, field investigations were performed using sediment cores to evaluate benthic phytodetritus accumulation. Specifically, nutrient contents, TOC/TN ratios, pigmentation, and biodegradable compounds were measured as descriptive parameters. The results show that the benthic bioclastic deposit had accumulated abundant pigments, nutrients, and biodegradable compounds derived from macrophytes detritus. These were mainly localized in the top 15 cm of sediments. Nitrogen loading in the sediments was significantly higher than phosphorous loading, with a distinct spatial difference; the total nitrogen content ranged from 127.2-2092.8 mg·kg-1 and total phosphorous content ranged from 222.1-528.4 mg·kg-1. Moreover, nitrogen loading (1033.6 mg·kg-1) in the vegetated zones were higher than in the unvegetated zones (325.2 mg·kg-1). In addition, carbohydrate (3.7 mg·g-1) was the dominant component of sedimentary bioclastic material, with lipids (2.8 mg·g-1) being the second most abundant of the biodegradable compounds. The major sources of nutrients and biodegradable compounds in the sediment were massive aggregates of macrophyte detritus. The pigment, nutrient, and biodegradable compound contents in the vegetated zones were significantly higher than in unvegetated zones (P<0.01). The benthic eutrophic state showed a trend from mesotrophic to eutrophic in Xukou Bay, which should be given more attention in the future management of freshwater lake ecosystems.


Assuntos
Ecossistema , Monitoramento Ambiental , Lagos , China , Eutrofização , Sedimentos Geológicos , Nitrogênio , Fósforo
9.
J Thorac Dis ; 11(5): 1831-1837, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31285875

RESUMO

Background: The current regimens for advanced non-small cell lung cancer (NSCLC) patients are deficient due to failings in standard treatments. This retrospective study aimed to assess the efficacy and safety of low-dose apatinib in combination with S-1 therapy in a NSCLC setting. Methods: In this retrospective study, advanced NSCLC patients who failed standard treatment in Changzhou Cancer Hospital of Soochow University were screened for eligibility. Progression-free survival (PFS) was set as the primary endpoint. Overall response rate (ORR), disease control rate (DCR), overall survival (OS), and the safety profile were considered to be the secondary endpoints. Results: A total of 31 eligible patients were included. The median PFS (mPFS) was 102 days (95% CI: 57-147 days). ORR was achieved in 7 patients (22.6%; 95% CI: 11.1-38.2%) and DCR was maintained in 23 patients (74.2%; 95% CI: 58.2-86.5%). The median OS (mOS) was 422 days (95% CI: 148-696 days). Patients with a history of smoking tended to have a shorter OS without significant differences (HR =4.105, 95% CI: 0.874-19.288, P=0.074). Treatment-related grade III toxicity was observed in 5 patients (16%) and common grade I or II adverse events (AEs) were fatigue (42%), hypertension (32%), and hand-foot-skin reaction (23%). Conclusions: Combination of low-dose apatinib and S-1 could be an effective and tolerable choice for advanced NSCLC patients who are unable to benefit from standard treatment; however, further exploration in larger clinical trials is needed.

10.
Onco Targets Ther ; 12: 1071-1074, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30799936

RESUMO

The heterogeneity of ALK tyrosine-kinase inhibitor (TKI) responses poses a puzzling question to clinicians. Different variants of ALK rearrangements might be one of the mechanisms explaining this phenomenon. Therefore, identifying specific fusion forms is crucial to clinical practice. This case report assesses the clinical efficacy of an ALK-TKI in a new ALK-rearrangement variant. Next-generation sequencing was performed in tumor tissue of one lung adenocarcinoma patient, and one new fusion form of an ALK rearrangement (NCOA1-ALK) was identified. This patient had progression-free survival >18 months with crizotinib treatment. Our findings provide valuable information about responses to crizotinib in patients with this form of ALK rearrangement and better understanding of ALK-TKI applications.

11.
Environ Sci Pollut Res Int ; 26(8): 7476-7485, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30659484

RESUMO

Sediment resuspension has been recognized as a crucial internal process in aquatic ecosystems. However, there is still a lack of reliable measuring methods due to the complex hydrodynamic conditions in large shallow eutrophic lakes. In this study, sequential sediment traps (SST) and instantaneous multiple point (IMP) methods were compared at 6 sites located in the littoral zone of Zhushan Bay in Lake Taihu. Results show that the average resuspension rates (RRs) estimated using the IMP method at sites 1 to 6 were 266.39, 272.79, 235.17, 254.95, 392.25, and 483.85 g·m-2d-1, respectively. While the RRs estimated using the SST method were 195.16, 236.99, 116.76, 156.23, 389.53, and 509.85 g·m-2d-1, respectively. In wind-disturbed areas, both methods were suitable for RR analysis in large and shallow eutrophic lakes and SST provides high-resolution temporal RR estimations. However, in the areas with cyanobacterial blooms and vegetation cover, the IMP method overestimated the RR. Therefore, SST was more suitable across different conditions in large and shallow eutrophic lakes, providing a simple, accurate, and high-resolution temporal estimation of RR, while furthering our understanding of lake evolution processes.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/análise , Lagos/química , Vento , China , Ecossistema , Ecótipo , Eutrofização , Hidrodinâmica
12.
J Integr Plant Biol ; 61(6): 749-764, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30387549

RESUMO

DNA methylation plays a crucial role in suppressing mobilization of transposable elements and regulation of gene expression. A number of studies have indicated that DNA methylation pathways and patterns exhibit distinct properties in different species, including Arabidopsis, rice, and maize. Here, we characterized the function of DDM1 in regulating genome-wide DNA methylation in maize. Two homologs of ZmDDM1 are abundantly expressed in the embryo and their simultaneous disruption caused embryo lethality with abnormalities in cell proliferation from the early stage of kernel development. We establish that ZmDDM1 is critical for DNA methylation, at CHG sites, and to a lesser extent at CG sites, in heterochromatic regions, and unexpectedly, it is required for the formation of m CHH islands. In addition, ZmDDM1 is indispensable for the presence of 24-nt siRNA, suggesting its involvement in the RdDM pathway. Our results provide novel insight into the role of ZmDDM1 in regulating the formation of m CHH islands, via the RdDM pathway maize, suggesting that, in comparison to Arabidopsis, maize may have adopted distinct mechanisms for regulating m CHH.


Assuntos
Metilação de DNA/genética , Proteínas de Plantas/metabolismo , Zea mays/genética , Genes de Plantas , Mutação com Perda de Função/genética , Fenótipo , Proteínas de Plantas/genética , RNA Interferente Pequeno/metabolismo , Sementes/embriologia , Sementes/genética , Zea mays/embriologia
13.
Plant J ; 98(1): 71-82, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30556198

RESUMO

Root hair, a special type of tubular-shaped cell, outgrows from the root epidermal cell and plays important roles in the acquisition of nutrients and water, as well as interactions with biotic and abiotic stresses. Studies in the model plant Arabidopsis have revealed that root-hair initiation and elongation are hierarchically regulated by a group of basic helix-loop-helix (bHLH) transcription factors (TFs). However, knowledge regarding the regulatory pathways of these bHLH TFs in controlling root hair growth remains limited. In this study, RNA-seq analysis was conducted to profile the transcriptome in the elongating maize root hair and >1000 genes with preferential expression in root hair were identified. A consensus cis-element previously featured as the potential bHLH-TF binding sites was present in the regulatory regions for the majority of the root hair-preferentially expressed genes. In addition, an individual change in ZmLRL5, the highest-expressed bHLH-TF in maize root hair resulted in a dramatic reduction in the elongation of root hair, and rendered the growth of root hair hypersensitive to translational inhibition. Moreover, RNA-seq, yeast-one-hybrid and ribosome profile analysis suggested that ZmLRL5 may function as a key player in orchestrating the translational process by directly regulating the expression of translational processes/ribosomal genes during maize root hair growth.

14.
Onco Targets Ther ; 11: 8083-8088, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30519050

RESUMO

Purpose: Several studies have proved that single nucleotide polymorphisms (SNPs) of mismatch repair system genes are closely related to the development of colorectal cancer (CRC) by causing microsatellite instability, while effects of the SNPs of MMR system-related genes on the clinical outcomes of cytotoxic chemotherapy are less understood. The aim of this study explored the influence of MLH1 SNPs on clinical outcomes of first-line irinotecan-based chemotherapy in CRC. Patients and methods: A total of 125 metastatic colorectal cancer (mCRC) patients who received first-line irinotecan-based chemotherapy (none of them combined with bevacizumab or cetuximab) were enrolled in this study. Blood samples or formalin-fixed paraffin-embedded tissues of study population were taken. DNA isolation and genotyping analyzed were obtained for potential functional polymorphisms of MLH1 rs1800734 by real-time PCR. Progression-free survival (PFS) was the primary endpoint and tumor response rate (RR) was the secondary endpoint of this study. Results: Of all the assessable population, the result showed no statistical difference among the three types SNPs of MLH1 rs1800734 (AA, AG, GG) for RR (P=0.859), and also without significant difference for AA + AG combined variants vs GG variant (P=0.849). The median PFS for AA, AG, and GG variants of MLH1 rs1800734 SNPs were 9.4 months, 7.0 months, and 6.9 months, respectively (log-rank P=0.031). Interestingly, compared with AA variant of MLH1 rs1800734 SNPs, GG variant showed a shorter PFS (HR: 3.49; 95 CI: 1.02-11.94; P=0.046). Furthermore, the median PFS of AA + AG combined variants and GG variant were 8.3 months and 6.9 months (log-rank P=0.037), and GG variant have a decreased trend with no significant difference (HR: 1.57; 95 CI: 0.98-2.53; P=0.061). Conclusion: The AA variant of MLH1 rs1800734 SNPs has a longer PFS in first-line irinotecan-based chemotherapy for mCRC patients, and the result needs to be further confirmed by prospective studies in the future.

15.
World Neurosurg ; 110: e333-e338, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29129762

RESUMO

OBJECTIVE: To study the clinical and morphologic characteristics associated with risk factors for the rupture of intracranial aneurysms (IAs). METHODS: A total of 1115 consecutive patients with 1282 IAs were reviewed from August 2011 to February 2016. The patients and IAs were divided into ruptured and unruptured groups. Based on the clinical and morphologic findings, the risk factors for IA rupture were assessed using statistical methods. RESULTS: Age, hypertension, diabetes mellitus, and cerebral atherosclerosis were associated with ruptured IAs. IAs located in the anterior cerebral artery, the anterior communicating artery, the posterior communicating artery, and the internal carotid artery were associated with ruptured IAs. Ruptures were also associated with arterial bifurcations, irregular aneurysm shapes, and all continuous data, except neck width. Binary logistic regression showed that IAs located at bifurcations (odds ratio [OR], 1.804), with irregular shapes (OR, 4.677), with high aspect ratios (ARs) (OR, 5.037) or with small mean diameters (MDs) (OR, 0.495) are more prone to rupture. Receiver operating characteristic analysis showed that the threshold values of the AR and MD were 1 and 3.70 mm, respectively. CONCLUSIONS: Morphologic characteristics, such as being located at bifurcations, being irregularly shaped, having a high AR (>1), and having a small MD (<3.70 mm), were better predictors of rupture.


Assuntos
Aneurisma Roto/diagnóstico por imagem , Angiografia Cerebral , Angiografia por Tomografia Computadorizada , Aneurisma Intracraniano/diagnóstico por imagem , Área Sob a Curva , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Curva ROC , Estudos Retrospectivos , Fatores de Risco
17.
Huan Jing Ke Xue ; 38(1): 95-103, 2017 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965035

RESUMO

To reveal the spatiotemporal characteristics of nutrients in the deposition process of suspended solids in lakeside zone,in situ deposition tests were performed in the western lakeside of Taihu Lake,and the contents of TP,TN,NH4+-N and NO3--N were measured and analyzed.The results showed that the deposition fluxes in the western lakeside of Taihu Lake ranked as follows:artificial reed areas >non-vegetation nearshore areas >natural reed areas >non-vegetation offshore areas,with their average values of (1383.40±925.60),(1208.67±743.50),(278.72±142.53),(245.58±154.25) g·(m2·d)-1,respectively.From the 6th day,the deposition volume steadily increased,with the deposition rate larger than the decomposition rate.Through the 15-day continuous in situ observation,the content of TP in nearshore zone was 2-3 folds larger than that of offshore zone,and the content of NH4+-N was significantly different from that of NO3--N in the settlement bottle (P<0.01).The deposition volume was significantly and positively correlated to both TN and NH4+-N contents in the water column (P<0.01,n=42),suggesting that the TN and NH4+-N contents in the overlying water increased with the deposition fluxes.The correlation coefficient between TN and NH4+-N was 0.84,implicating that the increase of deposition flux may accelerate the mutual transformation between different forms of nitrogen.These findings should be taken into account in the current control of black blooms and nutrient management in Taihu Lake.

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