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1.
AAPS J ; 24(1): 3, 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34850298

RESUMO

When there are multiple reference products, (e.g., EU-approved product and US-licensed product), a pharmacokinetic/pharmacodynamic (PK/PD) bridging study is often conducted in order to bridge the clinical data from the original region (e.g., Europe) to the new region (e.g., USA) in support of the biosimilar regulatory submission in the new region. The purpose is to avoid duplicated clinical trials for clinical similarity between a proposed biosimilar product and the reference product in the new region provided that there is no ethnic concern in the two regions. In this article, some innovative statistical designs for PK/PD biosimilar bridging studies are proposed. Statistical model and methods under the proposed statistical designs are studied. Power analysis for sample size requirement based on Schuirmann's two one-sided tests procedure is also derived and compared to pairwise testing using simulation.

2.
Front Plant Sci ; 12: 754887, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34858458

RESUMO

The allometric relationship among different functional traits is an ecological strategy for plants to promote resource utilization, which indicates the ability of plants to adapt to environmental changes coordinately. In this study, we conducted a field survey on Haloxylon ammodendron and H. persicum among different terrains (dune crest, eastern slope, western slope and inter-dune) in the Gurbantunggut Desert, obtained their quantitative and morphological characteristics, and analyzed their allometric relationships between plant height and canopy radius, plant height and basal diameter by using standardized major axis estimation. We found that: (1) The dominated terrains of H. ammodendron and H. persicum were different; (2) The individual morphology of the two Haloxylon species changed significantly with the terrains (p < 0.05), with the largest and smallest ones growing on the eastern slope and the inter-dune lowland, respectively; (3) Fixed allometric patterns were observed in the above-ground parts of the two Haloxylon species, as the growth of canopy and basal stem was preferentially to plant height; (4) These allometric relationships were significantly affected by the terrain, and exhibited discrepancy between two species, they both invested less in plant height in windy habitats, such as the dune crest and western slope, but H. ammodendron growing on the western slope and H. persicum growing on the eastern slope invested more in basal diameter for strengthening mechanical support and resources acquisition, respectively. These results indicated that both studied species adopted an ecological strategy that allocating more resources to horizontal expansion rather than vertical growth, the terrain has an important influence on the allometric relationship of their above-ground parts, and the trade-off mechanism of main components investing was different for these two species due to habitat heterogeneity and ecological adaptability.

3.
Front Oncol ; 11: 734853, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34858816

RESUMO

Immune checkpoint blockade (ICB), particularly programmed death 1 (PD-1) and its ligand (PD-L1), has shown considerable clinical benefits in patients with various cancers. Many studies show that PD-L1 expression may be biomarkers to help select responders for anti-PD-1 treatment. Therefore, it is necessary to elucidate the molecular mechanisms that control PD-L1 expression. As a potential chemosensitizer and anticancer drug, disulfiram (DSF) kills tumor cells via regulating multiple signaling pathways and transcription factors. However, its effect on tumor immune microenvironment (TIME) remains unclear. Here, we showed that DSF increased PD-L1 expression in triple negative breast cancer (TNBC) cells. Through bioinformatics analysis, we found that DNMT1 was highly expressed in TNBC tissue and PD-L1 was negatively correlated with IRF7 expression. DSF reduced DNMT1 expression and activity, and hypomethylated IRF7 promoter region resulting in upregulation of IRF7. Furthermore, we found DSF enhanced PD-L1 expression via DNMT1-mediated IRF7 hypomethylation. In in vivo experiments, DSF significantly improved the response to anti-PD-1 antibody (Ab) in 4T1 breast cancer mouse model. Immunohistochemistry staining showed that granzyme B+ and CD8+ T cells in the tumor tissues were significantly increased in the combination group. By analyzing the results of the tumor tissue RNA sequencing, four immune-associated pathways were significantly enriched in the DSF joint anti-PD-1 Ab group. In conclusion, we found that DSF could upregulate PD-L1 in TNBC cells and elucidated its mechanism. Our findings revealed that the combination of DSF and anti-PD-1 Ab could activate TIME to show much better antitumor efficacy than monotherapy.

4.
Adv Nanobiomed Res ; 1(7): 2000092, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34746928

RESUMO

Electrical microstimulation has shown promise in restoring neural deficits in humans. Electrodes coated with materials like the conducting polymer poly(3,4-ethylenedioxythiophene) doped with acid-functionalized carbon nanotubes (PEDOT/CNTs, or PC) exhibit superior charge injection than traditional metals like platinum. However, the stimulation performance of PC remains to be fully characterized. Advanced imaging techniques and transgenic tools allow for real-time observations of neural activity in vivo. Herein, microelectrodes coated with PC and iridium oxide (IrOx) (a commonly used high-charge-injection material) are implanted in GCaMP6s mice and electrical stimulation is applied while imaging neuronal calcium responses. Results show that PC-coated electrodes stimulate more intense and broader GCaMP responses than IrOx. Two-photon microscopy reveals that PC-coated electrodes activate significantly more neuronal soma and neuropil than IrOx-coated electrodes in constant-voltage stimulation and significantly more neuronal soma in constant-current stimulation. Furthermore, with the same injected charge, both materials activate more spatially confined neural elements with shorter pulses than longer pulses, providing a means to tune stimulation selectivity. Finite element analyses reveal that the PC coating creates a denser and nonuniform electric field, increasing the likelihood of activating nearby neural elements. PC coating can significantly improve energy efficiency for electrical stimulation applications.

6.
Front Genet ; 12: 743738, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34721530

RESUMO

N6-methyladenosine (m6A) RNA modification can alter gene expression and function by regulating RNA splicing, stability, translocation, and translation. It is involved in various types of cancer. However, its role in gliomas is not well known. This study aimed to determine the prognostic value of the m6A RNA methylation regulator in gliomas and investigate the underlying mechanisms of the aberrant expression of m6A-related genes.mRNA expression profiles and clinical information of 448 glioma samples were obtained from The Cancer Genome Atlas and cBioportal. The expression of m6A-related genes in normal controls and low-grade glioma and glioblastoma was obtained from Gene Expression Profiling Interactive Analysis. Further, m6A-related gene expression and its relationship with prognosis were obtained through The Chinese Glioma Genome Atlas (CGGA). Multivariate Cox regression analyses were performed, and a nomogram was built with potential risk factors based on a multivariate Cox analysis to predict survival probability. Online tools such as Gene Set Enrichment Analysis, STRING, Cytoscape, and Molecular Complex Detection were applied for bioinformatics analysis and to investigate the underlying mechanisms of the aberrant expression of m6A-related genes. The multivariate Cox regression analysis found that higher expression levels of YTHDC2 and insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3, also called IMP3) were independent negative and positive prognostic factors for overall survival (OS), respectively. Data from the CGGA database showed that IGF2BP3 expression increased when the tumor grade increased. Receiver operating characteristic (ROC) curve was used to evaluate the predictive specificity and sensitivity. The area under the ROC curve indicated that the OS prediction was 0.92 (1-year) and 0.917 (3-years), indicating that m6A-related genes could predict patient survival. In addition, IGF2BP3 was closely related to the shorter survival period of patients. Copy number variation and DNA methylation, but not somatic mutations, might contribute to the abnormal upregulation of IGF2BP3 in gliomas. Significantly altered genes were identified, and the protein-protein interaction network was constructed. Based on the data presented, our study identified several m6A-related genes, especially IGF2BP3, that could be potential prognostic biomarkers of gliomas. The study unveiled the potential regulatory mechanism of IGF2BP3 in gliomas.

7.
Ophthalmic Epidemiol ; : 1-11, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34766539

RESUMO

PURPOSE: To determine differences in cycloplegic vs. non-cycloplegic refractive error and factors associated with these differences in Chinese school students. METHOD: In this cross-sectional school-based study, refractive error was measured in school students using a NIDEK autorefractor before and after administration of 0.5% tropicamide. Spherical equivalent (SER) in diopters (D) was calculated as sphere plus half cylinder. SER differences before vs. after cycloplegia were evaluated using mean, standard deviation (SD), 95% limits of agreement. Univariable and multivariable regression models were used to determine factors associated with SER differences. RESULTS: Among 3604 students, 3450 (95.7%) provided data for analysis. Mean age (SD) was 9.7 (3.6) years. The mean SER (SD) was -1.12 (1.97) D before cycloplegia, and -0.20 (2.19) D after cycloplegia, with a mean difference of 0.92 D (95% limits of agreement: -0.93 to 2.78 D). Among 196 eyes with non-cycloplegic SER -6.0 D or worse (e.g., met high myopia definition), 71.4% had cycloplegic SER -6.0 D or worse, and among 3607 eyes with non-cycloplegic SER -0.5 D or worse (e.g., met myopia definition), 62.1% eyes had cycloplegic SER -0.5 D or worse. Cycloplegic SER was more correlated with axial length than non-cycloplegic SER (Pearson r = 0.82 vs. 0.72, p < .0001). In multivariable analysis, larger SER differences were associated with more hyperopic refractive error and smaller axial length (all p < .0001). CONCLUSION: Non-cycloplegic refractive error overestimates myopia by approximately one diopter. This overestimation increases with more hyperopic refractive error and smaller axial length. Non-cycloplegic refractive error should not be used for evaluating pediatric myopia. ABBREVIATIONS: BCVA = best corrected visual acuity; D = diopter; SD = standard deviation; SE = standard error; SER = spherical equivalent; CI = confidence interval.

8.
Clin Appl Thromb Hemost ; 27: 10760296211055716, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34730016

RESUMO

OBJECTIVE: Deep vein thrombosis (DVT) is one of the severe complications after total knee arthroplasty (TKA). Gender has been considered to influence the incidence of the thrombosis formation in TKA patients. However, it remains controversial which gender would be more prone to form thrombosis. The aim of this study was to assess the effects of gender differences on coagulation status after TKA via the thromboelastography (TEG). METHODS: A total of 57 male patients who underwent primary TKA from September 2015 to January 2021 were included in this study. According to the matching principle of age, body mass index (BMI), and anticoagulation treatment, 60 female patients were selected. The conventional coagulation tests, routine blood tests, and thromboelastography were conducted before the operation, 1 day and 7 days after the operation. In addition, Doppler ultrasound was also performed 1 day before the operation and at the 7 days after the operation. The parameters of conventional coagulation tests, routine blood tests, and thromboelastography were compared between the two groups. RESULTS: There were no significant differences in the blood transfusion rate, the incidence of DVT during the perioperative period, D-dimer (D-D), fibrin degradation products (FDP), hemoglobin (HB), hematocrit (HCT), prothrombin time (PT), activated partial thromboplastin time (APTT), and C-reactive protein (CRP) at any corresponding time point between the male group and the female group (P > .05). There were no significant differences in neutrophil-to-lymphocyte ratio (NLR) preoperatively; however, there were significant differences in NLR 1 day after the surgery and 7 days after the surgery between the two groups (P < .05). There were significant differences in reaction time (R) and α angle 1 day after the surgery between the two groups (P < .05), but there were no significant differences in other TEG indexes at any corresponding time point between the two groups (P > .05). Binary logistic regression analysis demonstrated that gender, age, BMI, tourniquet application time were not independent predictors (P > .05). CONCLUSION: Gender differences have no significant influence in TKA patients with regard to conventional coagulation tests and thromboelastography.

9.
J Ultrasound Med ; 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34751450

RESUMO

PURPOSES: To evaluate the postsurgical prognostic implication of contrast-enhanced ultrasound (CEUS) for combined hepatocellular-cholangiocarcinoma (CHC). To build a CEUS-based early recurrence prediction classifier for CHC, in comparison with tumor-node-metastasis (TNM) staging. METHODS: The CEUS features and clinicopathological findings of each case were analyzed, and the Liver Imaging Reporting and Data System categories were assigned. The recurrence-free survival associated factors were evaluated by Cox proportional hazard model. Incorporating the independent factors, nomograms were built to estimate the possibilities of 3-month, 6-month, and 1-year recurrence and whose prognostic value was determined by time-dependent receiver operating characteristics, calibration curves, and hazard layering efficiency validation, comparing with TNM staging system. RESULTS: In the multivariable analysis, the levels of carbohydrate antigen 19-9, prothrombin time and total bilirubin, and tumor shape, the Liver Imaging Reporting and Data System category were independent factors for recurrence-free survival. The LR-M category showed longer recurrence-free survival than did the LR-4/5 category. The 3-month, 6-month, and 1-year area under the curves of the CEUS-clinical nomogram, clinical nomogram, and TNM staging system were 0.518, 0.552, and 0.843 versus 0.354, 0.240, and 0.624 (P = .048, .049, and .471) vs. 0.562, 0.545, and 0.843 (P = .630, .564, and .007), respectively. The calibration curves of the CEUS-clinical model at different prediction time pionts were all close to the ideal line. The CEUS-clinical model effectively stratified patients into groups of high and low risk of recurrence in both training and validation set, while the TNM staging system only works on the training set. CONCLUSIONS: Our CEUS-clinical nomogram is a reliable early recurrence prediction tool for hepatocellular-cholangiocarcinoma and helps postoperative risk stratification.

10.
Phys Rev Lett ; 127(17): 176401, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34739291

RESUMO

Multifold degenerate fermions have attracted a lot of research interest in condensed matter physics and materials science, but always lack in two dimensions. In this Letter, from symmetry analysis and lattice model construction, we demonstrate that eightfold degenerate fermions can be realized in two-dimensional systems. In nonmagnetic materials with negligible spin-orbit coupling, the gray magnetic space groups together with SU(2) spin rotation symmetry can protect the two-dimensional eightfold degenerate fermions on a certain high-symmetry axis in the Brillouin zone, no matter whether the system is centrosymmetric or noncentrosymmetric. In antiferromagnetic materials, the eightfold degenerate fermions can also be protected by certain "spin space groups." Furthermore, by first-principles electronic structure calculations, we predict that the paramagnetic phase of the monolayer LaB_{8} on a suitable substrate is a two-dimensional eightfold degenerate as well as Dirac node-line semimetal. Especially, the eightfold degenerate points are close to the Fermi level, which makes monolayer LaB_{8} a good platform to study the exotic physical properties of two-dimensional eightfold degenerate fermions.

11.
Clin Cancer Res ; 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34740925

RESUMO

PURPOSE: To establish RP2D in Phase 1 and evaluate safety and efficacy of abivertinib in EGFR T790M+ NSCLC patients with disease progression from prior EGFR inhibitors in Phase 2. PATIENTS AND METHODS: This multicenter, open-label study included 367 adult Chinese patients. Abivertinib at doses of 50mg BID to 350 mg BID was evaluated in Phase 1 in continual 28-day cycles, and the RP2D of 300 mg BID was used in Phase 2 in continual 21-day cycles. Primary endpoints include RP2D in phase 1 and objective response rate (ORR) at RP2D in phase 2. RESULTS: The RP2D of 300 mg BID for abivertinib was established based on pharmacokinetics, efficacy and safety profiles across doses in Phase 1. In Phase 2, 227 patients received RP2D for a median treatment duration of 24.6 weeks (0.43-129). Among 209 response evaluable patients, confirmed ORR was 52.2% (109/209; 95% CI: 45.2%, 59.1%). Disease control rate (DCR) was 88.0% (184/209, 95% CI: 82.9%, 92.1%). The median duration of response (DoR) and progression-free survival (PFS) was 8.5 months (95% CI: 6.1, 9.2) and 7.5 months (95% CI: 6.0, 8.8), respectively. The median OS was 24.9 months (95% CI: 22.4, NR). All (227/227) patients reported at least 1 AE, with 96.9% (220/227) of treatment-related AE. Treatment-related serious AEs were reported in 13.7% (31/227) of patients. Death was reported in 4.4% (10/227) of patients, and none was deemed as treatment related. CONCLUSION: Abivertinib of 300 mg BID demonstrated favorable clinical efficacy with manageable side-effects in patients with EGFR T790M+NSCLC.

13.
Ocean Coast Manag ; 215: 105974, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34803244

RESUMO

The sudden outbreak of COVID-19 has led beach tourism to a complete halt in January 2020, disrupting millions of livelihoods and businesses. Due to the economic importance of beach tourism, many governments reopened tourist beaches after the number of confirmed cases decreased. It is essential to open beaches orderly to meet the needs of tourists, maintain beach's health and restore coastal economy under the new reality. This paper selected Qingdao in China as a case study, drew on a questionnaire survey among beach tourists, summarized the effects of the COVID-19 on beach tourism industry and tourism enterprise, analyzed beach tourists' psychology and behavior, and developed beach management strategy under the ongoing prevention and control of COVID-19. The results showed that the COVID-19 pandemic caused severe damage to beach tourism which bases on travel and mobility, and this industry was temporarily suspended. With the changing epidemic situation, beach tourism witnessed a gradual recovery from stagnation to local tourism. Meanwhile, tourism enterprises were hit by the devastating impact of the COVID-19, causing problems such as business reduction, tense cash flow, high operating cost and unclear market prospect. Under the normalization of pandemic prevention, tourists did not have severe fear and anxiety about the pandemic, and placed great importance on the prevention and control measures, emergency measures and pandemic risk level of the beach destination. The pandemic also reshaped the perception and mode of beach tourism. Ecological tourism, travelling with family, and local tourism became the primary choices for tourists. Beach congestion, health status, and the quality of tourism services were the biggest concerns for tourists. Additionally, social media and short video APP became the new marketing channels. Finally, beach management strategies were proposed from the aspects of pandemic prevention and control, emergency management, information communication, tourist management, service management, and environmental management.

14.
Bioresour Technol ; : 126268, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34737052

RESUMO

A high-performance biochar derived from the residue of Chaga mushroom (Inonotus obliquus) was reported in this study. Inonotus obliquus residues were used to prepare biochar, and the optimal synthesis conditions were obtained by response surface methodology. The specific surface area, pore volume, and average pore size of the optimal biochar (Zn-IORBC) was 1676.78 m2/g, 1.87 cm3/g, and 3.88 nm, respectively. Methylene blue (MB) and tetracycline (TC) were selected to estimate the adsorption performance of Zn-IORBC. The adsorption process was suitable for the pseudo-second-order model and Langmuir model. Zn-IORBC could maintained a large amount of TC adsorption (the lowest value was 686.20 mg/g in mountain spring water) in different natural water. The maximum adsorption capacity of TC and MB was 947.42 and 1033.66 mg/g. The adsorption mechanism was contributed to the electrostatic attraction, hydrogen bonding, π-π interactions, and pore-filling. Zn-IORBC is an effective adsorbent for high-performance pollutants removal.

15.
Artigo em Inglês | MEDLINE | ID: mdl-34807499

RESUMO

Fluorescent single crystals that respond to multiple external stimuli are of great interest in molecular machines, sensors, and displays. The integration of photo- or acid-induced fluorescence enhancement and bending in one organic crystal, however, has not been reported yet. Herein, we report the interesting plastic photomechanical bending and switching on of the fluorescence of an azine crystal in a single-crystal transformation, due to extended π-conjugation and molecular slippage. Moreover, the fluorescent plastic bending driven by multiple volatile acid vapors was firstly observed, and attributed to the synergistic effect of push-pull electronic structure and hydrogen bonding. The single crystal also shows high elasticity under external force. In addition, reversible fluorescence switching can be triggered by grinding and solvent fuming, as well as by the adsorption and desorption of HCl vapor. The integration of plastic, elastic bending and switch-on fluorescence into one single crystal provides a new strategy for next-generation smart materials.

16.
FEBS J ; 2021 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-34741776

RESUMO

Retinal pigment epithelium (RPE) cell damage is implicated in the pathogenesis of age-related macular degeneration (AMD). An increase of interferon-γ (IFN-γ) levels was observed in patients with AMD, but whether inflammatory factors are causally related to AMD progression is unclear. Here, we demonstrate a direct causal relationship between IFN-γ and RPE cell death. IFN-γ induced human retinal pigment epithelial cell (ARPE-19) death accompanied by increases in Fe2+ , reactive oxygen species, lipid peroxidation, and glutathione (GSH) depletion, which are main characteristics of ferroptosis. Mechanistically, IFN-γ upregulates the level of intracellular Fe2+ through inhibiting Fe2+ efflux protein SLC40A1 and induces GSH depletion by blocking cystine/glutamate antiporter, System xc-. At the same time, treatment with IFN-γ decreases the level of glutathione peroxidase 4 (GPx4), rendering the cells more sensitive to ferroptosis. JAK1/2 and STAT1 inhibitors could reverse the reduction of SLC7A11, GPx4 and GSH expression induced by IFN-γ, indicating IFN-γ induces ARPE-19 cell ferroptosis via activation of the JAK1-2/STAT1/SLC7A11 signaling pathway. The above results were largely confirmed in IFN-γ-treated mice in vivo. Finally, we used sodium iodate (NaIO3 )-induced retinal degeneration to further explore the role of ferroptosis in AMD in vivo. Consistent with the role of IFN-γ, treatment with NaIO3 decreased SLC7A11, GPx4 and SLC40A1 expressions. NaIO3 -induced RPE damage was accompanied by increased iron, lipid peroxidation products (4-hydroxynonenal, malondialdehyde), and GSH depletion, and ferroptosis inhibitors could reverse the above phenomenon. Taken together, our findings suggest that inhibiting ferroptosis or reducing IFN-γ may serve as a promising target for AMD.

17.
BMC Gastroenterol ; 21(1): 431, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34794374

RESUMO

PURPOSE: The aim of the study is to explore the independent association of free triiodothyronine (FT3), free thyroxine (FT4) and thyroid stimulating hormone (TSH) with hepatic steatosis and insulin resistance. METHODS: A cross-sectional study of 88 overweight/obese adults who underwent anthropometric measurements [BMI, waist circumference (WC) and waist-to-height ratio (WHtR)], hepatic steatosis assessment (FibroScan) and thyroid-related hormones tests was conducted from 2018 to 2020 in Xiamen, China. RESULTS: Subjects with increasing tertiles of FT3 showed significantly higher levels of controlled attenuation parameter (CAP) ((295.4 ± 44.1, 290.1 ± 68.2 and 331.7 ± 43.6 (dB/m) for tertile 1-3, respectively, p = 0.007) and fatty liver index (FLI) score (47.7 (33.9-60.8), 61.5 (45.1-88.9) and 90.5 (84.5-94.8), respectively, p < 0.001). FT3 significantly and positively correlated with obesity index (BMI, WC, and WHtR), homeostatic model assessment of insulin resistance (HOMA-IR) and hepatic steatosis (CAP and FLI). Multivariable linear regression analyses with adjustment for potential confounding factors showed FT3 was independently associated with BMI (regression coefficient (ß (95%CI): 0.024 (0.004-0.043), p = 0.020), HOMA-IR (ß (95%CI): 0.091 (0.007-0.174), p = 0.034), CAP (ß (95%CI): 25.45 (2.59-48.31), p = 0.030) and FLI (ß (95%CI): 0.121 (0.049-0.194), p = 0.001). Neither FT4 nor TSH was significantly associated with any indicators of obesity, insulin resistance or hepatic steatosis. CONCLUSIONS: Increased FT3, but not FT4 or TSH, was independently associated with higher risks of hepatic steatosis and insulin resistance in euthyroid overweight/obese Chinese adults. Trial registration Registration is not applicable for our study.


Assuntos
Fígado Gorduroso , Resistência à Insulina , Adulto , China , Estudos Transversais , Humanos , Obesidade/complicações , Sobrepeso/complicações , Glândula Tireoide , Hormônios Tireóideos , Tireotropina , Tiroxina , Tri-Iodotironina
18.
Sci Total Environ ; : 151616, 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34774937

RESUMO

Triclosan (TCS) is a broad-spectrum antimicrobial agent commonly used in pharmaceuticals and personal care products (PPCPs). The widespread use of TCS makes it frequently detected in various environmental mediums. In view of the high detection frequency of TCS in the aquatic environment and sediments, and its toxic effects on aquatic species, it is critical and necessary to derive Chinese TCS water quality criteria (WQC) and sediment quality criteria (SQC) for protecting Chinese aquatic organisms, and perform the ecological risk assessment. In fact, former research had derived the WQC of TCS mainly based on acute and chronic toxicity data. As an endocrine disrupting chemical (EDC), TCS poses adverse effects on the growth, development and reproduction of aquatic organisms at much lower concentration. Considering nonlethal endpoints are sensitive endpoints for EDCs, TCS long-term water quality criteria (LWQC) was derived based on reproduction and growth related endpoints. In this work, the acute toxicity data of 19 aquatic organisms and the chronic toxicity data of 15 aquatic organisms were obtained through collection and screening. The best fitting model of species sensitivity distribution (SSD) models including Normal, Log-Normal, Logistic and Log-Logistic of toxicity data was selected to derive WQC. The short-term and long-term WQC of TCS for Chinese aquatic organisms were 6.22 µg/L and 0.25 µg/L, respectively. Furthermore, through the phase-equilibrium partitioning method, SQC was derived based on WQC. SQC-low (SQC-L) and SQC-high (SQCH) were 0.13 mg/kg and 3.26 mg/kg, respectively. Moreover, the exposure concentration (EPC) data of TCS in Chinese rivers and sediments were collected. And through the hazard quotient (HQ) method and the joint probability curve (JPC) method we found that there were certain TCS ecological risks in Chinese rivers and sediments. Our work will provide a valuable reference for protecting aquatic organisms and minimizing TCS ecological risk in China.

19.
Sci Total Environ ; : 151791, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34808185

RESUMO

The minimization of Cd pollution in wheat is urgently needed in many parts of the world. Thus, the aims of the present study were to evaluate the feasibility of popular technologies (i.e., soil amendment and low-Cd wheat cultivar) at sites with different Cd risk levels (high and low) and to propose a risk-based strategy for safe grain production. At a high-Cd site, wheat variety JM22 yielded significantly lower grain Cd than SX828, regardless of soil amendment (biochar, sepiolite, and microbial agent YZ1). Neither biochar nor sepiolite amendment reduced grain Cd, DTPA-Cd, or bioconcentration factors, possibly due to low dosage. Metagenomic sequencing and quantitative PCR showed that YZ1 colonization had little effect on rhizospheric fungal community structure and could not be sustained through winter. At a low-Cd site, significantly lower grain Cd was observed in JM22, LX99, and JM262, which could be used as low-Cd cultivars in the study area. Interestingly, the grain Cd of JM22 was linearly correlated with soil Cd (R2 = 0.84), which allowed the inference of a soil Cd threshold of 1.55 mg·kg-1, below which JM22 alone was capable of producing safe grain. Cost-benefit analysis also indicated that the use of low-Cd cultivars is promising for pollution control. This study provides viable technical solutions for minimizing the grain Cd of wheat grown in northern China.

20.
Endocr Connect ; 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34822342

RESUMO

OBJECTIVE: Anti-Müllerian hormone (AMH) is recognized as the most important biomarker for ovarian reserve. In this cross-sectional study, we aimed to explore the potential association of AMH with central obesity or general obesity in women with polycystic ovary syndrome (PCOS). METHODS: In this cross-sectional study, 179 patients with PCOS were enrolled and underwent anthropometric measurements (BMI and waist circumference (WC)) and serum AMH level detection. Pearson's correlation and multivariable logistic regression analyses were performed to determine associations of AMH with central obesity and general obesity. RESULTS: Subjects with the increasing of body mass index (BMI) showed significantly lower values of AMH (median (IQR) 8.95 (6.03-13.60) ng/mL in normal weight group, 6.57 (4.18-8.77) ng/mL in overweight group, and 6.03 (4.34-9.44) ng/mL in obesity group, respectively, p=0.001), but higher levels of systolic blood pressure, fasting insulin, total cholesterol, triglycerides, low-density lipoprotein cholesterol, and obesity indices (WC, hip circumferences, waist-to-hip ratio (WHR), waist-to-height ratio (WHtR) and Chinese visceral adiposity index (CVAI)) respectively. Compared with the group of PCOS women without central obesity, the group with central obesity had significantly lower value of AMH (median (IQR) 8.56(5.29-12.96) vs. 6.22(4.33-8.82) ng/mL; p=0.003). Pearson's correlation analysis showed that AMH were significantly and negatively correlated with BMI (r=-0.280; p<0.001), WC (r=-0.263; p<0.001), WHtR (r=-0.273; p<0.001), and CVAI (r=-0.211; p=0.006) respectively. Multivariate logistic regression analysis with adjustment for potential confounding factors showed that AMH was independently and negatively associated with central obesity, but was not significantly associated with general obesity. CONCLUSIONS: AMH was independently and negatively associated with central obesity. Closely monitoring WC and AMH should be addressed in terms of assessing ovarian reserve in women with PCOS.

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