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1.
Anal Bioanal Chem ; 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34643770

RESUMO

Accurate measurement of plasma metanephrines (MNs) including metanephrine (MN) and normetanephrine (NMN) is crucial for the screening and diagnosis in pheochromocytomas and paragangliomas (PPGLs). Although the number of laboratories using liquid chromatography tandem mass spectrometry (LC-MS/MS) method to measure MNs has been increasing rapidly, those laboratory-developed assays showed incomparable results. There are no reference measurement procedures (RMPs) or reference materials (RMs) for MNs in Joint Committee for Traceability in Laboratory Medicine (JCTLM), which hindered the standardization of MNs measurement. We established a candidate RMP (cRMP) based on isotope dilution liquid chromatography tandem mass spectrometry (ID-LC/MS/MS) method for plasma MNs measurement. Plasma samples were spiked with MN-D3 and NMN-D3 as internal standards; protein precipitation and ion-exchange solid phase extraction (SPE) were performed to extract samples, eventually analyzed by LC-MS/MS. The cRMP was applied to evaluate two routine ID-LC/MS/MS methods through split-sample comparisons. Fifty-three individual patient samples were determined by cRMP and two routine ID-LC/MS/MS methods; results were analyzed by ordinary linear regression and Bland-Altman plots. The cRMP exhibited desirable imprecision, with intra-run and total imprecision (coefficient variation, CV) for MN being 0.79-1.36% and 1.53-1.87% and for NMN being 1.10-1.34% and 1.15-1.64%. The analytical recoveries of MN and NMN ranged from 98.3 to 101.7% and from 98.5 to 101.9%, respectively. Significant calibrator biases and sample-specific deviations were observed in method comparison. An accurate, precise, and reliable cRMP for plasma MNs was developed, and RMs with value assigned following the cRMP would help minimize the calibration bias and improve the comparability of different measuring systems.

2.
Artigo em Inglês | MEDLINE | ID: mdl-34636991

RESUMO

PURPOSE: Cyclase-associated protein 1 (CAP1) is a ubiquitous protein which regulates actin dynamics. Previous studies have shown that S308 and S310 are the two major phosphorylated sites in human CAP1. In the present study, we aimed to investigate the role of CAP1 phosphorylation in lung cancer. METHODS: Massive bioinformatics analysis was applied to determine CAP1's role in different cancers and especially in lung cancer. Lung cancer patients' serum and tissue were collected and analyzed in consideration of clinical background. CAP1 shRNA-lentivirus and siRNA were applied to CAP1 gene knockdown, and plasmids were constructed for CAP1 phosphorylation and de-phosphorylation. Microarray analysis was used for CAP1-associated difference analysis. Both in vitro and in vivo experiments were performed to investigate the roles of CAP1 phosphorylation and de-phosphorylation in lung cancer A549 cells. RESULTS: CAP1 is a kind of cancer-related protein. Its mRNA was overexpressed in most types of cancer tissues when compared with normal tissues. CAP1 high expression correlated with poor prognosis. Our results showed that serum CAP1 protein concentrations were significantly upregulated in non-small cell lung cancer (NSCLC) patients when compared with the healthy control group, higher serum CAP1 protein concentration correlated with shorter overall survival (OS) in NSCLC patients, and higher pCAP1 and CAP1 protein level were observed in lung cancer patients' tumor tissue compared with adjacent normal tissue. Knockdown CAP1 in A549 cells can inhibit proliferation and migration, and the effect is validated in H1975 cells. It can also lead to an increase ratio of F-actin/G-actin. In addition, phosphorylated S308 and S310 in CAP1 promoted lung cancer cell proliferation, migration, and metastasis both in vitro and in vivo. When de-phosphorylated, these two sites in CAP1 showed the opposite effect. Phosphorylation of CAP1 can promote epithelial-mesenchymal transition (EMT). CONCLUSION: These findings indicated that CAP1 phosphorylation can promote lung cancer proliferation, migration, and invasion. Phosphorylation sites of CAP1 might be a novel target for lung cancer treatment.

3.
Artigo em Inglês | MEDLINE | ID: mdl-34605141

RESUMO

Nanofluidic devices have been widely used for diode-like ion transport and salinity gradients energy conversion. Emerging reverse electrodialysis (RED) nanofluidic systems based on nanochannel membrane display great superiority in salinity gradient energy harvesting. However, the imbalance between permeability and selectivity limits their practical application. Here, we fabricate a new mesoporous carbon-silica/anodized aluminum (MCS/AAO) nanofluidic device with enhanced permselectivity for temperature- and pH-regulated energy generation. A maximum power density of 5.04 W/m2 is achieved, and a higher performance can be obtained by regulating temperature and pH. Theoretical calculations are further implemented to reveal the mechanism for ion rectification, ion selectivity and energy conversion. Results show that the MCS/AAO hybrid membrane has great superiority in diode-like ion transport, temperature- and pH-regulated salinity gradient energy conversion.

4.
Mol Med ; 27(1): 130, 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34666670

RESUMO

BACKGROUND: HPV16 is the predominant cancer-causing strain that is responsible for over 50% of all cervical cancers. In this study, we aim to investigate the therapeutic effect of heat shock protein 90 (Hsp90) knockdown on HPV16+ cervical cancer progression and the underlying mechanism. METHODS: The transcript and protein expression of Hsp90 in normal cervical and HPV16+ cervical cancer tissues and cell lines were detected by qRT-PCR, immunohistochemistry staining and Western blot. Hsp90 knockdown clones were established using HPV16+ cervical cancer cell line Caski and SiHa cells. The effect of Hsp90 knockdown on HER2/PI3K/AKT pathway and PD-L1 expression was characterized using qRT-PCR and Western blot analysis. Cell proliferation and migration were determined using MTT and transwell assays. Using mouse xenograft tumor model, the impact of Hsp90 knockdown and PD-L1 overexpression on tumor progression was evaluated. RESULTS: Hsp90 expression was up-regulated in HPV16+ cervical cancer tissues and cells. Knockdown of Hsp90 inhibited proliferation and migration of Caski and SiHa cells. PD-L1 expression in cervical cancer tissues was positively correlated with Hsp90 expression, and Hsp90 regulated PD-L1 expression via HER2/PI3K/AKT signaling pathway. The results of mouse xenograft tumor model demonstrated Hsp90 knockdown suppressed tumor formation and overexpression of PD-L1 simultaneously eliminated the cancer-suppressive effect of Hsp90 knockdown. CONCLUSION: In this study, we demonstrated a promising tumor-suppressive effect of Hsp90 knockdown in HPV16+ cervical cancers, and investigated the underlying molecular pathway. Our results suggested that Hsp90 knockdown holds great therapeutic potential in treating HPV16+ cervical cancers.

5.
Sci Total Environ ; : 150985, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34662621

RESUMO

Antibiotic resistance is a major threat to human health. It is necessary to explore all the potential sources and comprehend the pathways that antibiotic resistance genes (ARGs) are transmitted. In this study, by applying high-throughput quantitative PCR and high-throughput sequencing, ARGs and microbial community structure were determined, to understand the reservoirs and spread of ARGs in the Xilingol grassland system. A total of 151,140 and 138 different ARGs were observed in manure, soil, and water samples, respectively. Only 12 ARGs were shared in all environmental and animal manure samples. Multidrug defense system, such as efflux pump, was the most dominant factor in manure and soil samples, followed by antibiotic deactivation processes. These genes coffering resistance to major classes of antibiotics including ß_Lactamase (blaSFO, fox5, blaCTX-M-04, blaOXY), vancomycin (vanC-03, vanXD), MLSB (vatE-01, mphA-01), aminoglycoside (aadA2-01), Multidrug (oprJ) and others (oprD, qacEdelta1-02), except sulfonamide and tetracycline. The 12 ARGs were significantly enriched in water samples compared to manure and soil samples (p < 0.01) and demonstrated that the water environment was an important transmission source of ARGs in the grassland. The highest enrichment was up to 324.5-fold. Moreover, the 12 shared ARGs were positively correlated with the mobile genetic elements (p < 0.01). The nonrandom co-occurrence network patterns between ARGs and microbial community suggested that a total of three bacterial phyla were viewed as the potential ARGs hosts. These findings indicate that ARGs were highly enriched in water samples, demonstrating that the water environment was a critical source and sink of ARGs in the grassland system. It may illuminate the mechanism stressing the effects of human activity on the occurrence and transmission of ARGs in the grassland system.

6.
Water Res ; 205: 117690, 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34614460

RESUMO

Secondary water supply systems (SWSSs) are characterized by long water stagnation and low levels of chlorine residuals, which may pose a high microbial risk to terminal users. In this study, the SWSSs of 12 residential neighborhoods in a metropolitan area of 5 million people in southeastern China were seasonally investigated to assess their microbial risks by determining more than 30 physicochemical and biological parameters. Although the microbiological quality of SWSS water met the requirements of the standards for drinking water quality of China, it did deteriorate in various aspects. The heterotrophic plate counts with R2A media were high (> 100 CFU/mL) in some SWSS tank and tap water samples. Propidium monoazide (PMA)-qPCR revealed a one magnitude higher abundance of viable bacteria in the tank and tap water samples (average 103.63±1.10 and 103.65±1.25 gene copies/mL, respectively) compared with the input water samples, and Enterococcus, Acanthamoeba, and Hartmannella vermiformis were only detected in the tanks. In particular, the high detection frequency of Legionella in 35% tank and 21% tap water samples suggested it is a supplementary microbial safety indicator in SWSSs. The microbial regrowth potential was more obvious in summer, and Illumina sequencing also demonstrated distinct seasonal changes in the relative abundance of bacterial gene sequences at the genus level. Turbidity and residual chlorine were closely connected with total bacterial biomass, and the latter seemed responsible for microbial community structure alteration. The extremely low chlorine residuals associated with a high abundance of total bacteria (as high as 106.48 gene copies/mL) and Legionella (as high as 106.71 gene copies/100 mL) in the closed valve tanks highlighted the high microbial risk increased by mishandling the operation of SWSSs. This study found that SWSSs possessed a higher microbial risk than the drinking water network, which suggested that the frequency and scope of monitoring the microbial risk of SWSSs in megacities should be strengthened for the purpose of waterborne epidemic disease prevention and control.

7.
Nat Nanotechnol ; 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34531557

RESUMO

Converting CO2 emissions, powered by renewable electricity, to produce fuels and chemicals provides an elegant route towards a carbon-neutral energy cycle. Progress in the understanding and synthesis of Cu catalysts has spurred the explosive development of electrochemical CO2 reduction (CO2RR) technology to produce hydrocarbons and oxygenates; however, Cu, as the predominant catalyst, often exhibits limited selectivity and activity towards a specific product, leading to low productivity and substantial post-reaction purification. Here, we present a single-atom Pb-alloyed Cu catalyst (Pb1Cu) that can exclusively (~96% Faradaic efficiency) convert CO2 into formate with high activity in excess of 1 A cm-2. The Pb1Cu electrocatalyst converts CO2 into formate on the modulated Cu sites rather than on the isolated Pb. In situ spectroscopic evidence and theoretical calculations revealed that the activated Cu sites of the Pb1Cu catalyst regulate the first protonation step of the CO2RR and divert the CO2RR towards a HCOO* path rather than a COOH* path, thus thwarting the possibility of other products. We further showcase the continuous production of a pure formic acid solution at 100 mA cm-2 over 180 h using a solid electrolyte reactor and Pb1Cu.

8.
PLoS One ; 16(9): e0257974, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34582500

RESUMO

Sichuan, China, has abundant genetic resources of sheep (Ovis aries). However, their genetic diversity and population structure have been less studied, especially at the genome-wide level. In the present study, we employed the specific-locus amplified fragment sequencing for identifying genome-wide single nucleotide polymorphisms (SNPs) among five breeds of sheep distributed in Sichuan, including three local pure breeds, one composite breed, and one exotic breed of White Suffolk. From 494 million clean paired-end reads, we obtained a total of 327,845 high-quality SNPs that were evenly distributed among all 27 chromosomes, with a transition/transversion ratio of 2.56. Based on this SNP panel, we found that the overall nucleotide diversity was 0.2284 for all five breeds, with the highest and lowest diversity observed in Mage sheep (0.2125) and Butuo Black (0.1963) sheep, respectively. Both Wright's fixation index and Identity-by-State distance revealed that all individuals of Liangshan Semifine-wool, White Suffolk, and Butuo Black sheep were respectively clustered together, and the breeds could be separated from each other, whereas Jialuo and Mage sheep had the closest genetic relationship and could not be distinguished from each other. In conclusion, we provide a reference panel of genome-wide and high-quality SNPs in five sheep breeds in Sichuan, by which their genetic diversity and population structures were investigated.

9.
Front Immunol ; 12: 735170, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34531875

RESUMO

The aim of this study was to elucidate the correlation between m6A modification and the tumor immune microenvironment (TIME) in prostate cancer (PCa) and to identify the m6A regulation patterns suitable for immune checkpoint inhibitors (ICIs) therapy. We evaluated the m6A regulation patterns of PCa based on 24 m6A regulators and correlated these modification patterns with TIME characteristics. Three distinct m6A regulation patterns were determined in PCa. The m6A regulators cluster with the best prognosis had significantly increased METTL14 and ZC3H13 expression and was characterized by low mutation rate, tumor heterogeneity, and neoantigens. The m6A regulators cluster with a poor prognosis had markedly high KIAA1429 and HNRNPA2B1 expression and was characterized by high intratumor heterogeneity and Th2 cell infiltration, while low Th17 cell infiltration and Macrophages M1/M2. The m6Ascore was constructed to quantify the m6A modification pattern of individual PCa patients based on m6A-associated genes. We found that the low-m6Ascore group with poor prognosis had a higher immunotherapeutic response rate than the high-m6Ascore group. The low-m6Ascore group was more likely to benefit from ICIs therapy. This study was determined that immunotherapy is more effective in low-m6Ascore PCa patients with poor prognosis.

10.
Chin Med J (Engl) ; 134(18): 2166-2174, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34553699

RESUMO

BACKGROUND: The effectiveness of bronchial thermoplasty (BT) has been reported in patients with severe asthma. This study compared the effects of BT and cryoballoon ablation (CBA) therapy on the airway smooth muscle (ASM). METHODS: Eight healthy male beagle dogs were included in this experiment. In the preliminary experiment, one dog received BT treatment for both lower lobe bronchus, another dog received CBA treatment for 7 s on the upper and lower lobe of right bronchus, and 30 s on the left upper and lower lobe. The treatments were performed twice at an interval of 1 month. In subsequent experiments, the right lower lobe bronchus was treated with BT, and the left lower lobe bronchus was treated with CBA. The effects of treatment were observed after 1 (n = 3) month and 6 months (n = 3). Hematoxylin-eosin staining, Masson trichrome staining, and immunohistochemical staining were used to compare the effects of BT and CBA therapy on the ASM thickness, collagen fibers synthesis, and M3 receptor expression after treatment. One-way analysis of variance with Dunnett post hoc test was used to analyze the differences among groups. RESULTS: In the preliminary experiment, the ASM ablation effect of 30-s CBA was equivalent to that of 7-s CBA (ASM thickness: 30.52 ±â€Š7.75 µm vs. 17.57 ±â€Š15.20 µm, P = 0.128), but the bronchial mucociliary epithelium did not recover, and large numbers of inflammatory cells had infiltrated the mucosal epithelium at 1-month post-CBA with 30-s freezing. Therefore, we chose 7 s as the CBA treatment time in our follow-up experiments. Compared with the control group (35.81 ±â€Š11.02 µm), BT group and CBA group (13.41 ±â€Š4.40 µm and 4.81 ±â€Š4.44 µm, respectively) had significantly decreased ASM thickness after 1 month (P < 0.001). Furthermore, the ASM thickness was significantly lower in the 1-month post-CBA group than in the 1-month post-BT group (P = 0.015). There was no significant difference in ASM thickness between the BT and CBA groups after six months (9.92 ±â€Š4.42 µm vs. 7.41 ±â€Š7.20 µm, P = 0.540). Compared with the control group (0.161 ±â€Š0.013), the average optical density of the ASM M3 receptor was significantly decreased in 6-month post-BT, 1-month post-CBA, and 6-month post-CBA groups (0.070 ±â€Š0.022, 0.072 ±â€Š0.012, 0.074 ±â€Š0.008, respectively; all P < 0.001). There was no significant difference in the average optical density of ASM M3 receptor between the BT and CBA therapy groups after six months (P = 0.613). CONCLUSIONS: CBA therapy effectively ablates the ASM, and its ablation effect is equivalent to that of BT with a shorter onset time. A neural mechanism is involved in both BT and CBA therapy.


Assuntos
Termoplastia Brônquica , Criocirurgia , Animais , Brônquios/cirurgia , Broncoscopia , Cães , Humanos , Masculino , Músculo Liso
11.
Acta Trop ; 224: 106125, 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34508714

RESUMO

Trichinella spiralis is a major foodborne zoonotic parasitic nematode which has a serious threat to meat food safety. Development of anti-Trichinella vaccine is requisite for control and elimination of Trichinella infection in food animals to ensure meat safety. Aminopeptidase P (TsAPP) and cathepsin X (TsCX) are two novel proteins identified in T. spiralis intestinal infectious L1 larvae (IIL1). The objective of this study was to investigate the protective immunity elicited by immunization with TsAPP and TsCX alone and TsAPP-TsCX in combination in a mouse model. The results demonstrate that subcutaneous vaccination of mice with rTsAPP, rTsCX or rTsAPP + rTsCX elicited a systemic humoral response (high levels of serum IgG, IgG1/IgG2a and IgA) and significant local gut mucosal sIgA responses. The vaccination with rTsAPP, rTsCX or rTsAPP + rTsCX also induced a systemic and local mixed Th1/Th2 response, as demonstrated by clear elevation levels of IFN-γ and IL-4 in vaccinated mice. Vaccination of mice with rTsAPP+rTsCX exhibited a 63.99 % reduction of intestinal adult worms and 68.50% reduction of muscle larva burdens, alleviated inflammation of intestinal mucosal and muscle tissues, and provided a higher immune protection than that of vaccination with rTsAPP or rTsCX alone. The results demonstrated that TsAPP and TsCX might be considered novel candidate target molecules for anti-Trichinella vaccines.

12.
mSphere ; : e0054521, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34585961

RESUMO

Most studies of gut microbiota have focused on relationships between a specific disease and the presence/abundance of one or a few bacterial species/genera. Whether the spatial and temporal distribution of gut microbiota, as a whole, affects or correlates with health is unknown, largely due to the absence of tools for dynamically monitoring the overall gut microbiota landscape inside living subjects. Here, we describe a novel, noninvasive, live imaging method for gut microbiota using 2-deoxy-2-[18F]fluoro-d-sorbitol (18F-FDS), a compound that specifically labeled gut bacteria in mice and hamsters following oral administration. Positron emission tomography-computed tomography (PET-CT) scanning showed that the radiolabel signal was concentrated in the gut (especially the large intestine), was absent when mice gut microbiota was depleted by antibiotic treatment, and was restored after transplanting antibiotic-treated mice with a fecal or probiotic bacterial mixture. Thus, 18F-FDS images microbiota, not gut tissue. The tissue distribution of 18F-FDS was the highest in the gut (∼3-fold higher than average), in contrast to 2-deoxy-2-[18F]fluoro-d-glucose, which concentrated in brain and many other organs. 2-[18F]fluoro-aminobenzoic acid, another bacterium-specific radioactive tracer, was unsuited for gut microbiota imaging due to unexpected stomach retention following oral administration. When similar gut microbiota imaging was done with hamsters, the spatial resolution increased significantly over that with mice, suggesting that even higher spatial resolution can be achieved with humans or large animals. Thus, our work establishes a new tool for noninvasive, live imaging of gut microbiota; the new tool may enable exploration of relationships between gut microbiota landscape and diseases in clinical settings. IMPORTANCE Gut microbiota dysbiosis correlates with many diseases, but such correlations derive mostly from relationships between one or a few bacteria and a particular disease. Since microbiota resemble complex forest ecosystems more closely than individual patches of trees, the overall landscape (spatial and temporal distribution) of gut bacteria may also affect/reflect disease development. Such a possibility has not been explored due to a lack of tools for directly visualizing natural landscape patterns of gut microbiota. The present work identified 2-deoxy-2-[18F]fluoro-d-sorbitol as a gut microbiota-specific radioactive tracer and developed a novel PET-CT scan-based imaging method that enables noninvasive, real-time imaging of the overall gut bacterial landscape. The method showed increased spatial resolution when hamsters replaced mice, suggesting that even higher spatial resolution could be achieved with larger animals such as humans. This novel technology establishes the feasibility of investigating spatial-temporal distribution dynamics of gut microbiota with many human diseases.

14.
Nutr Cancer ; : 1-13, 2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34472414

RESUMO

We aimed to investigate the association between folate intake and the risk of urothelial carcinoma (UC). A systematic literature search using Pubmed and EMBASE databases was performed to find prospective cohort studies, population-based case-control study or hospital-based case-control study investigating the association of folate intake and the risk of UC. A total of 19 studies involving 11,175 cases and 656,161 individuals were included. High intake of folate was associated with a decreased risk of UC, with a pooled OR of 0.78 (95% CI: 0.66-0.93, P = 0.006) for the highest category of intake vs. the lowest. The data suggested that folate may contribute to the prevention of urothelial cancer. However, the association was observed only in case-control studies (OR = 0.56, 95% CI: 0.39-0.79, P = 0.001), but not in cohort studies (RR = 0.97, 95% CI: 0.87-1.09, P = 0.638). Dose-response meta-analysis showed that an increment of folate intake (100 µg/day) corresponded to an 8% deceased risk of invasive UC (RR = 0.92, 95% CI: 0.87-0.98, P = 0.004). High folate intake might be inversely associated with risk of UC particularly invasive UC, which needs to be confirmed.

15.
Nano Lett ; 2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34410722

RESUMO

CO2 electroreduction powered by renewable electricity represents a promising method to enclose anthropogenic carbon cycle. Current catalysts display high selectivity toward the desired product only over a narrow potential window due primarily to unoptimized intermediate binding. Here, we report a functional ligand modification strategy in which palladium nanoparticles are encapsulated inside metal-organic frameworks with 2,2'-bipyridine organic linkers to tune intermediate binding and thus to sustain a highly selective CO2-to-CO conversion over widened potential window. The catalyst exhibits CO faradaic efficiency in excess of 80% over a potential window from -0.3 to -1.2 V and reaches the maxima of 98.2% at -0.8 V. Mechanistic studies show that the 2,2'-bipyridine on Pd surface reduces the binding strength of both *H and *CO, a too strong binding of which leads to competing formate production and CO poison, respectively, and thus enhances the selectivity and stability of CO product.

16.
Yi Chuan ; 43(8): 747-757, 2021 Aug 20.
Artigo em Chinês | MEDLINE | ID: mdl-34413015

RESUMO

The Cpx (conjugative pilus expression) two-component signal transduction system is a complex envelope stress response system in Gram-negative bacteria, which can sense a variety of extracellular stimuli that enter the signaling pathway at different points. The phosphorylation of the CpxR, the cytoplasmic cognate response regulator of the Cpx system, can lead to changes in the expression of genes encoding proteins involved in inner and outer membrane functions. Activation of the Cpx system contributes to bacterial resistance/tolerance to certain antibiotics and acidic stress. In this review, we summarize the composition, and the mechanisms of signal detection, and the transcriptional regulation of the Cpx system, with a goal to provide guidance for the study of the regulatory network of the Cpx system and its important regulatory roles in bacterial physiology.


Assuntos
Proteínas de Bactérias , Transdução de Sinais , Proteínas de Bactérias/genética , Bactérias Gram-Negativas
17.
Huan Jing Ke Xue ; 42(9): 4267-4274, 2021 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-34414724

RESUMO

Karst water, which provides approximately 25% of the world's drinking water, is especially vulnerable to anthropogenic pollutants. To determine the variations between high and low flow periods and the sources of dissolved sulfate (SO42-) in small karst basins, SO42- concentrations, stable sulfur and oxygen isotopes (δ34S-SO4 and δ18O-SO4), and oxygen isotopes of water (δ18O-H2O) were investigated in surface and groundwaters, during the high and low flow seasons, within the Babu subterranean stream basin. Analysis showed that: ① the water samples that were directly impacted by acid mine drainage exhibited high SO42- concentrations (≥250 mg·L-1) and significant seasonal variation, while the seasonal variation of non-AMD-impacted water with low SO42- concentrations was not significant. ② During the high flow season, the mean δ34S-SO4 and δ18O-SO4 values of surface water were -10.5‰ and 4.7‰, respectively, and -11.5‰ and 1.3‰ during the low flow period; the mean values of δ34S-SO4 and δ18O-SO4 in groundwater samples were -2.9‰ and 7.1‰ during the high flow period, respectively, and -3.2‰ and 6.2‰ during the low flow period. Both surface and groundwater samples exhibited higher δ34S-SO4 and δ18O-SO4 values during the high flow period than during the low flow period. ③ The values of δ34S-SO4 in the surface and groundwater samples were relatively stable, indicating that the sources of SO42- at specific sampling sites were stable.④ The main sources of SO42- in surface and groundwaters were rain, sulfide, and gypsum, accounting for 13%, 40%, and 47%, respectively, of SO42- in samples taken from the basin outlet during the high flow season, and 18%, 39%, and 43%, respectively, in samples obtained during the low flow season.


Assuntos
Monitoramento Ambiental , Rios , Isótopos de Oxigênio/análise , Estações do Ano , Sulfatos/análise , Enxofre
18.
Radiology ; : 204700, 2021 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-34427463

RESUMO

Background Two-dimensional (2D) shear-wave elastography (SWE) has been considered to be useful in predicting hepatocellular carcinoma (HCC) development in patients with chronic hepatitis B (CHB). Purpose To develop a risk model using 2D SWE to predict HCC in patients with CHB and to compare its predictive value with that of other models. Materials and Methods Patients with biopsy-proven CHB who underwent US and 2D SWE between April 2011 and December 2015 were enrolled in this study. After 2D SWE and biopsy were performed, the patients received regular follow-up for the detection of HCC. The scoring system was developed by dividing the parameters of the Cox proportional hazards model by the smallest parameter and simplifying the assigned points to integers. The predictive performance of the new score was compared with that of other scores. Results Among the 654 patients (mean age, 37 years; range, 30-43 years; 510 men), 26 developed HCC. The variables of age, platelet count, and liver stiffness measurement at 2D SWE were weighted to develop the so-called APS score, with a cutoff of 60 showing the best discrimination for HCC risk. The APS score (area under the receiver operating characteristic curve [AUC], 0.89) was superior to that of the Chinese University HCC prediction score constructed from age, albumin level, bilirubin level, hepatitis B virus (HBV) DNA level, and cirrhosis (AUC, 0.70; P = .005) and slightly higher than that of the guide with age, gender, HBV DNA level, core promoter mutations, and cirrhosis, or GAG-HCC score (AUC, 0.82; P = .052). In patients who underwent transient elastography, the AUC of the APS score was 0.79, compared with 0.82 for the modified risk estimation for HCC in CHB, or mREACH-B, score (P = .05). The APS score performed better in patients regardless of whether antiviral treatment was used, inflammation grade was low or high, or alanine aminotransferase levels were normal or high (all P > .05). Conclusion The APS score based on only the patient's baseline liver stiffness measurement at two-dimensional shear-wave elastography, age, and platelet count is valuable for predicting hepatocellular carcinoma in patients with chronic hepatitis B. © RSNA, 2021 Online supplemental material is available for this article.

19.
Nano Lett ; 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34460262

RESUMO

Surface functionalization with atoms serves as an important strategy to modulate the catalytic activities of low-dimensional nanomaterials. Herein, we developed a facile hydrogen incorporation strategy for improving the catalytic activities of SnS2 nanosheets toward CO2 electroreduction. Compared with SnS2 nanosheets, the hydrogen-incorporated SnS2 (denoted as H-SnS2) nanosheets exhibited high current density and Faradaic efficiency (FE) for formate. At -0.9 V vs RHE, H-SnS2 nanosheets displayed a maximum FE of 93% for carbonaceous product, which rivals the activities of most Sn-based catalysts in CO2 electroreduction. Mechanistic studies disclosed that the incorporation of surface hydrogen induced the electron injection into the structures of H-SnS2 nanosheets, which largely facilitates the process of CO2 activation. Density functional theory (DFT) calculations further revealed that hydrogen incorporation decreased the energy barrier for the formation of HCOO* intermediates, thus contributing to the CO2-to-formate conversion on H-SnS2 nanosheets.

20.
Diagn Cytopathol ; 49(9): 1052-1055, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34291890

RESUMO

OBJECTIVE: The parasite Trichomonas vaginalis (T. vaginalis) causes one of the most common non-viral sexually transmitted infections in humans. T. vaginalis is notorious for its inconspicuous appearance in vaginal smears. It can be missed under the microscope. METHOD: In the present study, we investigate the immunoreactivity of T. vaginalis to smooth muscle actin (SMA) in the vaginal smear. RESULT: T. vaginalis trophozoite and pseduocyst are immunoreactive for SMA in all of the study group cases (n = 21) and in none of the control group cases (n = 21). Thus, SMA immunostain is a sensitive method for the demonstration of T. vaginalis. Moreover, the protozoan attains a conspicuous and unique appearance. By SMA immunohistochemical stain, the apperance of T. vaginalis floated freely or located in the cytoplasm of the epithelial cells is easily identified. CONCLUSION: We recommend performing SMA immunostain in every vaginal smear with clinical or pathologic suspicion of trichomoniasis.

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