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1.
Ann Surg Oncol ; 31(4): 2443-2450, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37962741

ABSTRACT

BACKGROUND: Chemotherapy and chemoradiation have become essential adjuncts to improve the survival of patients with resectable esophageal squamous cell carcinoma (ESCC) in the perioperative period. Although preoperative treatment plus surgery is commonly used, controversy remains regarding the optimal treatment strategy for patients with locally advanced ESCC. METHODS: A retrospective review of clinical stage II and III ESCC patients who underwent esophagectomy at Henan Cancer Hospital between October 2014 and October 2017 was performed. The patients were divided into a neoadjuvant chemotherapy (NAC) group and an adjuvant chemotherapy (AC) group. Propensity score matching (PSM) was used to exclude confounders. Survival was estimated using Kaplan‒Meier analysis and compared by the log-rank test. The Cox proportional hazards regression model was used for both the univariate and multivariate analyses. RESULTS: A total of 684 patients were enrolled, including 365 (53.4%) patients in the NAC group. After PSM, 294 pairs of patients were left. NAC prolonged the OS (not reached versus 57.3 months, P = 0.002) and DFS (57.2 vs. 36.4 months, P = 0.010) and decreased the total rate of recurrence (50.1% vs. 59.2%, P = 0.025) and local recurrence (27.9% vs. 36.7%, P = 0.022) compared with AC. The multivariable analyses showed that NAC plus surgery modality was an independent predictor for improved OS (HR: 0.582, 95% CI: 0.467-0.786, P = 0.001). CONCLUSION: NAC plus surgery prolonged OS and DFS, and significantly decreased the total rate of recurrence compared with surgery plus AC in patients with clinical stage II and III ESCC.


Subject(s)
Esophageal Neoplasms , Esophageal Squamous Cell Carcinoma , Humans , Esophageal Squamous Cell Carcinoma/pathology , Esophageal Neoplasms/drug therapy , Esophageal Neoplasms/surgery , Neoadjuvant Therapy , Chemotherapy, Adjuvant , Chemoradiotherapy , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Esophagectomy , Retrospective Studies , Neoplasm Staging
2.
Dis Esophagus ; 37(1)2024 Jan 01.
Article in English | MEDLINE | ID: mdl-37455547

ABSTRACT

This study was completed to evaluate the relationship between tumor length and the prognosis of patients with pathological stage IA-IC esophageal adenocarcinoma (EAC). Patients were identified from the Surveillance, Epidemiology, and End Results Program database (United States, 2006-2015). X-tile software and ROC analysis were mainly used to explore the best threshold of tumor length for dividing patients into different groups, and then propensity score matching (PSM) was used to balance other variables between groups. The primary outcome assessed was overall survival (OS). A total of 762 patients were identified, and 500 patients were left after PSM. Twenty millimeters were used as the threshold of tumor length. Patients with longer tumor lengths showed worse OS (median: 93 vs. 128 months; P = 0.006). Multivariable Cox regression analysis showed that longer tumor length was an independent risk factor (hazard ratio 1.512, 95% confidence interval, 1.158-1.974, P = 0.002). Tumor length has an impact on patients with pathological stage IA-IC EAC who undergo surgery alone. The prognostic value of the pathological stage group may be improved after combining it with tumor length and age.


Subject(s)
Adenocarcinoma , Esophageal Neoplasms , Humans , United States , Prognosis , Neoplasm Staging , Adenocarcinoma/pathology , Esophageal Neoplasms/surgery , Esophageal Neoplasms/pathology , Propensity Score
3.
J Environ Manage ; 365: 121530, 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38905799

ABSTRACT

Atrazine is a widely used herbicide in agriculture, and it has garnered significant attention because of its potential risks to the environment and human health. The extensive utilization of atrazine, alongside its persistence in water and soil, underscores the critical need to develop safe and efficient removal strategies. This comprehensive review aims to spotlight atrazine's potential impact on ecosystems and public health, particularly its enduring presence in soil, water, and plants. As a known toxic endocrine disruptor, atrazine poses environmental and health risks. The review navigates through innovative removal techniques across soil and water environments, elucidating microbial degradation, phytoremediation, and advanced methodologies such as electrokinetic-assisted phytoremediation (EKPR) and photocatalysis. The review notably emphasizes the complex process of atrazine degradation and ongoing scientific efforts to address this, recognizing its potential risks to both the environment and human health.

4.
Ann Surg Oncol ; 30(8): 5205-5212, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37162643

ABSTRACT

PURPOSE: The purpose of this retrospective study was to define the pattern of lymph nodal metastases in patients with esophageal squamous cell carcinoma (ESCC) after neoadjuvant chemotherapy (NCT) followed by esophagectomy and to evaluate its influence on prognosis. METHODS: A total of 398 patients with clinical stage T3N0 or T1-3N+ ESCC who underwent NCT and radical esophagectomy with two-field lymphadenectomy were included. The distribution and frequency of metastases were counted separately for each lymph node station. The ypN stage, number of positive lymph node stations and lymph node stations with a metastasis rate greater than 5% were analyzed by using univariate Cox regression, followed by separate multivariable Cox regression analyses after adjusting for various clinical factors. RESULTS: Lymph node metastases were most frequently observed in the right upper paratracheal (16.8%) and left gastric artery (13.1%) stations. Multivariable models controlling for clinical factors showed that ypN stage remained a significant independent predictor of survival (N1 vs. N0: hazard ratio [HR], 2.30, 95% confidence interval [CI] 1.38-3.83, P < 0.001; N2 vs. N0: HR, 3.76, 95% CI 2.21-6.38, P < 0.001; N3 vs. N0: HR, 7.14, 95% CI 3.78-13.48, P < 0.001). The model from the multivariable analysis with the highest c-index score, indicating superior discriminatory preference, was ypN stage (c-index, 0.72). CONCLUSIONS: The pattern and influence of lymph node metastases after NCT will provide guidance on the extent of lymphadenectomy. Common positive lymph node stations for thoracic ESCC after NCT include the paratracheal, subcarinal, paraesophageal, paracardial, and left gastric artery stations.


Subject(s)
Carcinoma, Squamous Cell , Esophageal Neoplasms , Esophageal Squamous Cell Carcinoma , Humans , Esophageal Squamous Cell Carcinoma/surgery , Esophageal Squamous Cell Carcinoma/pathology , Esophageal Neoplasms/drug therapy , Esophageal Neoplasms/surgery , Carcinoma, Squamous Cell/drug therapy , Carcinoma, Squamous Cell/surgery , Neoadjuvant Therapy , Lymphatic Metastasis/pathology , Retrospective Studies , Follow-Up Studies , Lymph Nodes/surgery , Lymph Nodes/pathology , Lymph Node Excision , Esophagectomy , Neoplasm Staging
5.
Plant Cell Environ ; 46(1): 76-92, 2023 01.
Article in English | MEDLINE | ID: mdl-36289576

ABSTRACT

The spectral-based photochemical reflectance index (PRI) and leaf surface temperature (Tleaf ) derived from thermal imaging are two indicative metrics of plant functioning. The relationship of PRI with radiation-use efficiency (RUE) and Tleaf with leaf transpiration could be leveraged to monitor crop photosynthesis and water use from space. Yet, it is unclear how such relationships will change under future high carbon dioxide concentrations ([CO2 ]) and drought. Here we established an [CO2 ] enrichment experiment in which three wheat genotypes were grown at ambient (400 ppm) and elevated (550 ppm) [CO2 ] and exposed to well-watered and drought conditions in two glasshouse rooms in two replicates. Leaf transpiration (Tr ) and latent heat flux (LE) were derived to assess evaporative cooling, and RUE was calculated from assimilation and radiation measurements on several dates along the season. Simultaneous hyperspectral and thermal images were taken at ~ $\unicode{x0007E}$ 1.5 m from the plants to derive PRI and the temperature difference between the leaf and its surrounding air ( ∆ $\unicode{x02206}$ Tleaf-air ). We found significant PRI and RUE and ∆ $\unicode{x02206}$ Tleaf-air and Tr correlations, with no significant differences among the genotypes. A PRI-RUE decoupling was observed under drought at ambient [CO2 ] but not at elevated [CO2 ], likely due to changes in photorespiration. For a LE range of 350 W m-2 , the ΔTleaf-air range was ~ $\unicode{x0007E}$ 10°C at ambient [CO2 ] and only ~ $\unicode{x0007E}$ 4°C at elevated [CO2 ]. Thicker leaves in plants grown at elevated [CO2 ] suggest higher leaf water content and consequently more efficient thermoregulation at high [CO2 ] conditions. In general, Tleaf was maintained closer to the ambient temperature at elevated [CO2 ], even under drought. PRI, RUE, ΔTleaf -air , and Tr decreased linearly with canopy depth, displaying a single PRI-RUE and ΔTleaf -air  Tr model through the canopy layers. Our study shows the utility of these sensing metrics in detecting wheat responses to future environmental changes.


Subject(s)
Carbon Dioxide , Triticum , Water
6.
Phys Chem Chem Phys ; 25(42): 29192-29200, 2023 Nov 01.
Article in English | MEDLINE | ID: mdl-37870868

ABSTRACT

Carbon nanotubes and their composite thermoelectric (TE) materials have significant advantages in supplying power to flexible electronics due to their high electrical conductivity, excellent flexibility, and facile preparation technology. In this work, stable n-type silver ammonia-polyethyleneimine/single-walled carbon nanotube ([Ag(NH3)2]+-PEI/SWCNT) composite films were facilely prepared by solution blending and vacuum-filtration methods. The results demonstrate that light silver ammonia doping optimizes the carrier concentration and carrier mobility of the composite film, and a maximum power factor (PF) of [Ag(NH3)2]+-PEI/SWCNT of 91.9 µW m-1 K-2 was obtained, which is higher than that of PEI/SWCNT (70.0 µW m-1 K-2). Furthermore, when the composite films were reduced by the NaBH4 solution, the Seebeck coefficient and the PF value were further increased to -45.5 µV K-1 and 115.8 µW m-1 K-2, respectively. For demonstration, a maximum output voltage of 13.8 mV and output power of 492 nW were achieved using a three p-n junction-based TE device constructed by [Ag(NH3)2]+-PEI/SWCNT at a temperature difference of 50 K. Thus, this study provides a metal complex ion doping strategy to improve thermoelectrical properties and air stability of the PEI/SWCNT composite films, which have potential applications in flexible electronics.

7.
Future Oncol ; 19(26): 1777-1784, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37737025

ABSTRACT

No adjuvant treatment has been established for patients who remain at high risk of recurrence and incidental pathologic lymph node metastasis for esophageal squamous cell carcinoma (ESCC). In this open-label, multicenter, phase III, randomized controlled trial, ESCC patients who did not achieve pathologic complete response after neoadjuvant chemotherapy plus surgery and clinical T1-2 N0 patients with incidental pathologic lymph node metastasis following initial surgery were randomized at a 2:1 ratio to receive either a sintilimab regimen or observational management (NCT05495152). The primary end point was disease-free survival for all randomized patients. The results of this randomized controlled trial addressed controversy regarding the survival benefits of adjuvant sintilimab treatment for patients with resected locally advanced ESCC. Clinical Trial Registration: NCT05495152 (ClinicalTrials.gov).


Subject(s)
Esophageal Neoplasms , Esophageal Squamous Cell Carcinoma , Humans , Adjuvants, Immunologic , Esophageal Neoplasms/drug therapy , Esophageal Squamous Cell Carcinoma/drug therapy , Lymphatic Metastasis
8.
Dis Esophagus ; 36(5)2023 Apr 29.
Article in English | MEDLINE | ID: mdl-36385581

ABSTRACT

This study aimed to investigate the survival impact of the number of lymph nodes dissection (LND) in patients receiving neoadjuvant chemotherapy (NCT) for esophageal squamous cell carcinoma (ESCC). We retrospectively analyzed the clinical pathological data and survival of 407 ESCC patients who underwent esophagectomy after NCT between January 2015 and December 2016. The relationship between the number of LNDs and 5-year overall survival (OS) or disease-free survival (DFS) was plotted by using restricted cubic spline analysis. A Cox proportional hazards regression model was used to identify prognostic factors of OS and DFS. We observed an obvious non-linear relationship between LND and the hazard ratios (HRs) for OS (P = 0.0015) and DFS (P < 0.001) of all the patients. In the multivariate analysis of OS and DFS, the number of LNDs (greater than 28 and less than 46) had a significant protective effect on survival (OS: HR: 0.61, 95% CI: 0.42-0.88, P = 0.007; DFS: HR: 0.50, 95% CI: 0.36-0.70, P < 0.001). For patients with nodal metastases, it was also an independent prognostic factor for OS (HR, 0.56, 95% CI, 0.35-0.90, P = 0.017) and DFS (HR, 0.42, 95% CI, 0.28-0.65, P < 0.001). Some degree of lymphadenectomy after NCT was beneficial in improving 5-year OS and DFS for ESCC patients with nodal metastases. For patients with nodal negativity, more extended lymphadenectomy did not improve patient survival.


Subject(s)
Carcinoma, Squamous Cell , Esophageal Neoplasms , Esophageal Squamous Cell Carcinoma , Humans , Esophageal Squamous Cell Carcinoma/surgery , Esophageal Squamous Cell Carcinoma/pathology , Esophageal Neoplasms/drug therapy , Esophageal Neoplasms/surgery , Neoadjuvant Therapy , Carcinoma, Squamous Cell/drug therapy , Carcinoma, Squamous Cell/surgery , Retrospective Studies , Prognosis , Neoplasm Staging , Lymph Node Excision , Lymph Nodes/surgery , Lymph Nodes/pathology , Esophagectomy
9.
PLoS Genet ; 16(4): e1008462, 2020 04.
Article in English | MEDLINE | ID: mdl-32236090

ABSTRACT

In flowering plants, gene expression in the haploid male gametophyte (pollen) is essential for sperm delivery and double fertilization. Pollen also undergoes dynamic epigenetic regulation of expression from transposable elements (TEs), but how this process interacts with gene expression is not clearly understood. To explore relationships among these processes, we quantified transcript levels in four male reproductive stages of maize (tassel primordia, microspores, mature pollen, and sperm cells) via RNA-seq. We found that, in contrast with vegetative cell-limited TE expression in Arabidopsis pollen, TE transcripts in maize accumulate as early as the microspore stage and are also present in sperm cells. Intriguingly, coordinate expression was observed between highly expressed protein-coding genes and their neighboring TEs, specifically in mature pollen and sperm cells. To investigate a potential relationship between elevated gene transcript level and pollen function, we measured the fitness cost (male-specific transmission defect) of GFP-tagged coding sequence insertion mutations in over 50 genes identified as highly expressed in the pollen vegetative cell, sperm cell, or seedling (as a sporophytic control). Insertions in seedling genes or sperm cell genes (with one exception) exhibited no difference from the expected 1:1 transmission ratio. In contrast, insertions in over 20% of vegetative cell genes were associated with significant reductions in fitness, showing a positive correlation of transcript level with non-Mendelian segregation when mutant. Insertions in maize gamete expressed2 (Zm gex2), the sole sperm cell gene with measured contributions to fitness, also triggered seed defects when crossed as a male, indicating a conserved role in double fertilization, given the similar phenotype previously demonstrated for the Arabidopsis ortholog GEX2. Overall, our study demonstrates a developmentally programmed and coordinated transcriptional activation of TEs and genes in pollen, and further identifies maize pollen as a model in which transcriptomic data have predictive value for quantitative phenotypes.


Subject(s)
DNA Transposable Elements/genetics , Gene Expression Regulation, Plant , Genetic Fitness , Pollen/genetics , Transcription, Genetic , Zea mays/genetics , Cell Lineage , Gene Expression Profiling , Genes, Plant/genetics , Genome, Plant/genetics , Meiosis , Mutagenesis, Insertional , Mutation , Pollination , Reproducibility of Results , Reproduction , Seeds/genetics , Seeds/growth & development , Up-Regulation , Zea mays/cytology , Zea mays/growth & development
10.
Gene Ther ; 29(3-4): 193-205, 2022 04.
Article in English | MEDLINE | ID: mdl-32859986

ABSTRACT

Colorectal cancer (CRC) has been the third leading cause of cancer-associated deaths. LncRNA SNHG16 is reported to be involved in metastasis of CRC cells. However, the mechanism by which SNHG16 regulates CRC progression is poorly understood. The proliferation of CRC cells was examined by MTT. Wound healing and transwell assay were used to measure migration and invasion ability. RT-qPCR and western blot were used to examine gene expression. Immunofluorescence was conducted to evaluate the EMT of CRC cells. Luciferase reporter assay were used to confirm direct interaction between miR-124-3p and SNHG16 or MCP-1. The interaction between miR-124-3p and SNHG16 was detected by RIP and RNA pull down assay. H&E staining was used to test the histomorphological changes of hepatic metastatic nodules. Finally, xenograft tumor experiment was utilized to determine tumor growth in vivo. SNHG16 and miR-124-3p were dysregulated in human colorectal tumors or cells. Knockdown of SNHG16 led to attenuate cell proliferation, migration, invasion, and EMT of CRC cells. And xenograft tumor experiment showed that SNHG16 might influence tumor growth. In contrast, miR-124-3p exerted the antitumor effects. Knockdown of miR-124-3p can reverse the effect of sh-SNHG16 on CRC cells. miR-124-3p could directly bind to SNHG16 or MCP-1. More importantly, MCP-1 acts as a critical effector mediating the role of SNHG16/ miR-124-3p in CRC cells. In summary, our data suggest that SNHG16 plays a contributory role in proliferation, migration, and EMT of CRC cells via miR-124-3p/MCP-1 axis, which offers a rationale for targeting SNHG16 and developing therapeutic drugs to treat CRC.


Subject(s)
Colorectal Neoplasms , MicroRNAs , RNA, Long Noncoding , Cell Movement/genetics , Cell Proliferation/genetics , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Epithelial-Mesenchymal Transition/genetics , Humans , MicroRNAs/genetics , MicroRNAs/metabolism , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism
11.
Mol Ecol ; 31(22): 5813-5830, 2022 11.
Article in English | MEDLINE | ID: mdl-36168983

ABSTRACT

The endosymbiosis between most corals and their photosynthetic dinoflagellate partners begins early in the host life history, when corals are larvae or juvenile polyps. The capacity of coral larvae to buffer climate-induced stress while in the process of symbiont acquisition could come with physiological trade-offs that alter behaviour, development, settlement and survivorship. Here we examined the joint effects of thermal stress and symbiosis onset on colonization dynamics, survival, metamorphosis and host gene expression of Acropora digitifera larvae. We found that thermal stress decreased symbiont colonization of hosts by 50% and symbiont density by 98.5% over 2 weeks. Temperature and colonization also influenced larval survival and metamorphosis in an additive manner, where colonized larvae fared worse or prematurely metamorphosed more often than noncolonized larvae under thermal stress. Transcriptomic responses to colonization and thermal stress treatments were largely independent, while the interaction of these treatments revealed contrasting expression profiles of genes that function in the stress response, immunity, inflammation and cell cycle regulation. The combined treatment either cancelled or lowered the magnitude of expression of heat-stress responsive genes in the presence of symbionts, revealing a physiological cost to acquiring symbionts at the larval stage with elevated temperatures. In addition, host immune suppression, a hallmark of symbiosis onset under ambient temperature, turned to immune activation under heat stress. Thus, by integrating the physical environment and biotic pressures that mediate presettlement event in corals, our results suggest that colonization may hinder larval survival and recruitment under projected climate scenarios.


Subject(s)
Anthozoa , Dinoflagellida , Animals , Anthozoa/physiology , Symbiosis/genetics , Coral Reefs , Larva/genetics , Dinoflagellida/genetics , Heat-Shock Response/genetics
12.
Plant Cell Environ ; 45(12): 3445-3461, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36098352

ABSTRACT

The combination of a future rise in atmospheric carbon dioxide concentration ([CO2 ]) and drought will significantly impact wheat production and quality. Genotype phenology is likely to play an essential role in such an effect. Yet, its response to elevated [CO2 ] and drought has not been studied before. Here we conducted a temperature-controlled glasshouse [CO2 ] enrichment experiment in which two wheat cultivars with differing maturity timings and life cycle lengths were grown under ambient (aCO2 approximately 400 µmol mol-1 ) and elevated (eCO2 approximately 550 µmol mol-1 ) [CO2 ]. The two cultivars, bred under dry and warm Mediterranean conditions, were well-watered or exposed to drought at 40% pot holding capacity. We aimed to explore water × [CO2 ] × genotype interaction in terms of phenology, physiology, and agronomic trait response. Our results show that eCO2 had a significant effect on plants grown under drought. eCO2 boosted the booting stage of the late-maturing genotype (cv. Ruta), thereby prolonging its booting-to-anthesis period by approximately 3 days (p < 0.05) while unaffecting the phenological timing of the early-maturing genotype (cv. Zahir). The prolonged period resulted in a much higher carbon assimilation rate, particularly during pre-anthesis (+87% for Ruta vs. +22% for Zahir under eCO2 ). Surprisingly, there was no eCO2 effect on transpiration rate and grain protein content in both cultivars and under both water conditions. The higher photosynthesis (and transpiration efficiency) of Ruta was not translated into higher aboveground biomass or grain yield, whereas both cultivars showed a similar increase of approximately 20% in these two traits at eCO2 under drought. Overall, Zahir, the cultivar that responded the least to eCO2, had a more efficient source-to-sink balance with a lower sink limitation than Ruta. The complex water × [CO2 ] × genotype interaction found in this study implies that future projections should account for multifactor interactive effects in modeling wheat response to future climate.


Subject(s)
Droughts , Triticum , Triticum/genetics , Triticum/metabolism , Carbon Dioxide/metabolism , Water , Genotype
13.
Ecotoxicol Environ Saf ; 211: 111943, 2021 Mar 15.
Article in English | MEDLINE | ID: mdl-33493720

ABSTRACT

Pearl millet (Pennisetum americanum (L.) K. Schum) has been proven as a potential remediation plant of the pollution caused by atrazine. Plants used in remediation can release root exudates to communicate with rhizosphere microorganisms and accelerate the removal of pollutants in soil. However, the response of pearl millet root exudates under atrazine stress has remained unclear. In this study, hydroponic experiments were conducted at Northeast Agricultural University, Harbin, China, to investigate the oxidative stress response and the changes in composition of root exudates in pearl millet plants that were exposed to 19.4 mgL-1 of atrazine, compared to the untreated control. The experiment was established as six treatments with exposure to no atrazine for 2, 4 and 6 days (CK-2, CK-4, CK-6) and 19.4 mgL-1 atrazine for 2, 4 and 6 days (AT-2, AT-4, AT-6), respectively. The results suggest that the growth of the seedlings changed slightly when exposed to atrazine for 2 days. The content of thiobarbituric acid reactive substances exposed to atrazine for 6 days increased 26% compared with the treatment that was exposed for 2 days. Moreover, the reactive oxygen species in test plant obviously increased when exposed to atrazine for 6 days. In addition, the activity of superoxide dismutase increased from 30.82 ug-1 to 37.33 ug-1 fresh weight after 6 days of exposure to atrazine. The results of a nontargeted metabolomic analysis suggest that carbohydrate metabolism, fatty acid metabolism and amino acid metabolism in pearl millet were obviously affected by the oxidative stress caused by atrazine. The contents of sphinganine and methylimidazole acetaldehyde in CK-6 increased by 5.14 times and 2.05 times, respectively, compared with those of CK-2. Furthermore, the contents of (S)-methylmalonic acid semialdehyde and 1-pyrroline-2-carboxylic acid decreased by 0.56 times and 0.5 times, respectively, compared with the AT-6. These results strongly suggest that the changes observed in the composition of root exudates in pearl millet seedlings can be attributed to the oxidative stress caused by atrazine.


Subject(s)
Atrazine/toxicity , Herbicides/toxicity , Oxidative Stress/physiology , Pennisetum/drug effects , Plant Exudates/metabolism , Atrazine/metabolism , China , Herbicides/metabolism , Oxidation-Reduction , Pennisetum/metabolism , Pennisetum/physiology , Rhizosphere , Seedlings/metabolism , Soil/chemistry , Superoxide Dismutase/metabolism
14.
Environ Res ; 184: 109260, 2020 05.
Article in English | MEDLINE | ID: mdl-32113024

ABSTRACT

Atrazine is a widely used herbicide whose presence poses a potential threat to agriculture and human living environment. This work studied the degradation performances and mechanisms of zero-valent iron and biochar composite (ZVI/BC) activated persulfate (PS) for atrazine. The results showed that the removal percentage of atrazine reached 73.47% within 30 min. Furthermore, the optimal parameters (175 mg/L ZVI/BC, 2 mM PS and initial pH of 3) were obtained through response surface methodology. Meanwhile, the high atrazine removal percentage (83.77%) was obtained under the optimal conditions. Radical quenching studies and electron spin resonance revealed that active substances produced during PS activation, as well as that SO4·- and HO· were dominant active species for the atrazine degradation. According to iron corrosion products and XPS analysis, the reaction mechanism of ZVI/BC-PS system was proposed as that ZVI loaded on the composites further activated PS to produce SO4·- and HO· which accompany with the valent changing of iron and finally causing degradation of atrazine. In addition, the degradation pathways of atrazine in ZVI/BC-PS system included dealkylation, alkyl oxidation and dechlorination-hydroxylation by the results of GC-MS and LC-MS. These findings demonstrated that ZVI/BC activated persulfate may be an efficient technique for the degradation of atrazine.


Subject(s)
Atrazine , Water Pollutants, Chemical , Water Purification , Catalysis , Charcoal , Iron , Oxidation-Reduction
15.
Ecotoxicol Environ Saf ; 202: 110854, 2020 Oct 01.
Article in English | MEDLINE | ID: mdl-32585484

ABSTRACT

Atrazine as a kind of herbicide could cause damage to the sensitive plants. Though plant growth promoting rhizobacteria (PGPR) have been proven with the potential to enhance the resistance of plants against various abiotic stresses, whether it could alleviate phytotoxicity caused by atrazine is sill unclear. In present study, the effects of strain Pseudomonas chlororaphis PAS18, a kind of PGPR enable to produce indole-3-acetic acid (IAA), on the growth and physiological responses of Pennisetum americanum (L.) K.Schum seedlings were investigated under three different levels (0, 20 and 100 mg kg-1) of atrazine in pot experiment. The results suggest that strain PAS18 could alleviate the growth and physiological interference caused by 20 mg kg-1 of atrazine. Physiological analysis showed strain PAS18 could further decrease the damaged extent of photosystem II, superoxide radical level and malondialdehyde content of test plant via up-regulating psbA expression, enhancing superoxide dismutase activity and reducing atrazine accumulation in the test plant. Moreover, ion flux measurements suggest that IAA could alleviate the Ca2+ exflux state of the test plant which caused by atrazine stress. Hence, it is plausible that strain PAS18 could alleviate atrazine-induced stress to P. americanum by enhancing the photosystem II repair and antioxidant defense ability as well as balancing the Ca2+ flux.


Subject(s)
Atrazine/toxicity , Indoleacetic Acids/metabolism , Pennisetum/physiology , Pseudomonas chlororaphis/physiology , Antioxidants/metabolism , Atrazine/metabolism , Drug Tolerance , Herbicides/metabolism , Malondialdehyde/metabolism , Pennisetum/drug effects , Photosynthesis , Pseudomonas chlororaphis/metabolism , Seedlings/drug effects , Stress, Physiological
16.
Stat Probab Lett ; 1672020 Dec.
Article in English | MEDLINE | ID: mdl-33304024

ABSTRACT

When a statistical test is repeatedly applied to rows of a data matrix, correlations among data rows will give rise to correlations among corresponding test statistics. We investigate the relationship between test-statistic correlation and data-row correlation and discuss its implications.

17.
Am J Hum Genet ; 98(2): 243-55, 2016 Feb 04.
Article in English | MEDLINE | ID: mdl-26833331

ABSTRACT

In genetic association testing, failure to properly control for population structure can lead to severely inflated type 1 error and power loss. Meanwhile, adjustment for relevant covariates is often desirable and sometimes necessary to protect against spurious association and to improve power. Many recent methods to account for population structure and covariates are based on linear mixed models (LMMs), which are primarily designed for quantitative traits. For binary traits, however, LMM is a misspecified model and can lead to deteriorated performance. We propose CARAT, a binary-trait association testing approach based on a mixed-effects quasi-likelihood framework, which exploits the dichotomous nature of the trait and achieves computational efficiency through estimating equations. We show in simulation studies that CARAT consistently outperforms existing methods and maintains high power in a wide range of population structure settings and trait models. Furthermore, CARAT is based on a retrospective approach, which is robust to misspecification of the phenotype model. We apply our approach to a genome-wide analysis of Crohn disease, in which we replicate association with 17 previously identified regions. Moreover, our analysis on 5p13.1, an extensively reported region of association, shows evidence for the presence of multiple independent association signals in the region. This example shows how CARAT can leverage known disease risk factors to shed light on the genetic architecture of complex traits.


Subject(s)
Crohn Disease/genetics , Genetic Testing/methods , Adult , Female , Genetic Association Studies , Humans , Linear Models , Male , Middle Aged , Models, Genetic , Phenotype , Polymorphism, Single Nucleotide , Population Groups/genetics , Quantitative Trait, Heritable , Retrospective Studies , Young Adult
18.
Cancer Causes Control ; 30(12): 1365-1375, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31667711

ABSTRACT

PURPOSE: Age-related factors including oxidative stress play an important role in prostate carcinogenesis. We hypothesize that germline single-nucleotide polymorphisms (SNPs) in oxidative stress pathway are associated with prostate cancer (PCa) risk. In this study, we aim to examine which of these SNPs is associated with PCa. METHODS: Participants included in this analyses came from the "Genetic Susceptibility, Environment and Prostate Cancer Risk Study" conducted at the Veterans Affairs Portland Health Care System. After applying exclusion criteria, 231 PCa cases and 382 prostate biopsy-negative controls who had genotyping data on twenty-two single-nucleotide polymorphisms (SNPs) in six genes (MAPK14, NRF2, CAT, GPX1, GSTP1, SOD2, and XDH) associated with oxidative stress pathway were included in the analyses. The genotyping of SNPs was conducted by the Illumina BeadXpress VeraCode platform. We investigated these SNPs in relation to overall and aggressive PCa risk using logistic regression models controlling for relevant covariates. RESULTS: One SNP in the MAPK14 (rs851023) was significantly associated with incident PCa risk. Compared to men carrying two copies of allele A, the presence of one or two copies of the G allele was associated with decreased risk of PCa [OR (95% CI) 0.19 (0.06-0.51)]. There was no statistically significant association between other SNPs in the NRF2, CAT, GPX1, GSTP1, SOD2, and XDH genes and PCa risk. CONCLUSIONS: The MAPK14 gene SNP rs851023 was associated with PCa and aggressive PCa risk after multiple comparison adjustment. Further studies in other populations or functional studies are needed to validate the finding.


Subject(s)
Mitogen-Activated Protein Kinase 14/genetics , Oxidative Stress/genetics , Prostatic Neoplasms/genetics , Aged , Alleles , Case-Control Studies , Genetic Predisposition to Disease , Humans , Male , Middle Aged , Polymorphism, Single Nucleotide
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