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Polychlorinated naphthalenes (PCNs) are detrimental to human health and the environment. With the commercial production of PCNs banned, unintentional releases have emerged as a significant environmental source. However, relevant information is still scarce. In this study, provincial emissions for eight PCNs homologues from 37 sources in the Chinese mainland during the period of 1960-2019 were estimated based on a source-specific and time-varying emission factor database. The results showed that the total PCNs emissions in 2019 reached 757.0 kg with Hebei ranked at the top among all the provinces and iron & steel industry as the biggest source. Low-chlorinated PCNs comprised 90% of emissions by mass, while highly chlorinated PCNs dominated in terms of toxicity, highlighting divergent priorities for mitigating emissions and safeguarding human health. The emissions showed an overall upward trend from 1960 to 2019 driven by emission increase from iron & steel industry in terms of source, and from North China and East China in terms of geographic area. Per-capita emissions followed an inverted U-shaped environmental Kuznets curve while emission intensities decreased with increasing per-capita Gross Domestic Product (GDP) following a nearly linear pattern when log-transformed.

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In general, for most environmental persistent organic pollutants (POPs), dietary intake is the main way of exposure. Polychlorinated naphthalenes (PCNs) are a family of two-ringed aromatic compounds, which are ubiquitous environmental contaminants, being structurally similar to PCDD/Fs and PCBs. Although the production and use of PCNs were banned in the USA and Europe some decades ago, due to their persistent properties, PCNs remain still present in the environment, being able to enter the food chain. The present paper was aimed at reviewing the results of the studies focused on determining the levels of PCNs in foods. The human dietary intake of these compounds was also reviewed with the few available data. The information on the levels of PCNs in foodstuffs is currently more abundant than that found in a previous review (Domingo, 2004). Since then, China is the country that has contributed with the greatest number of studies. The results of most surveys seem to suggest that human health risks of PCNs due to dietary exposure should not be worrying. However, because of the important differences in the methodology of the published studies, the comparison of the results is not easy, although there seems to be a general trend towards a decrease in the levels of PCNs in foods. In the next few years, a continued reduction of the environmental levels of PCNs is still expected. Therefore, a direct repercussion of the concentrations of these pollutants in foodstuffs must be also noted. Consequently, a reduction of the dietary exposure to PCNs should be expected. Anyway, to establish the tolerable dietary intake of PCNs is a key issue for assessing human health risks of these pollutants.

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Background: Advances in imaging have improved the detection rate of pancreatic cystic neoplasms (PCNs), but clinical management varies depending on the pathological type of PCNs, and thus accurate differential diagnosis is of considerable clinical significance. We conducted this study to identify the clinical and sonographic features of PCNs with significance for differential diagnosis and to compare the diagnostic accuracy of conventional ultrasound and conventional ultrasound combined with contrast-enhanced ultrasound (CEUS) for PCNs. Methods: From January 1, 2011, to December 31, 2022, a total of 100 patients with PCNs who underwent CEUS examination and were confirmed to have PCNs by postoperative pathology in West China Hospital of Sichuan University were included in this study. Results: Of the clinical characteristics of PCNs, age and gender were found to be important differential diagnostic features. Moreover, communication of the lesion with the main pancreatic duct on conventional ultrasound and CEUS images was a critical feature in the differential diagnosis of intraductal papillary mucinous neoplasm (IPMN). The size of the lesion, the thickness of the cyst wall and the number of septa in conventional ultrasound images, the uniformity of the cyst wall thickness in CEUS images, and the enhancement pattern in the arterial phase were significant features for the differential diagnosis of serous cystic neoplasm (SCN). Cyst wall thickness and uniformity of the cyst wall thickness in conventional ultrasound images and cyst wall thickness and septa thickness in CEUS images were important features in the differential diagnosis of mucinous cystic neoplasm (MCN). The size and internal components of the lesion on conventional ultrasound images, internal components of the lesion, and the enhancement pattern in the arterial phase and rim enhancement on CEUS images were the key features in the differential diagnosis of solid pseudopapillary neoplasm (SPN). Conventional ultrasound combined with CEUS demonstrated significantly greater accuracy than did conventional ultrasound alone in the differential diagnosis of PCNs (66% vs. 79%; P=0.002). Conclusions: PCN types differ in their clinical and ultrasound features. Conventional ultrasound combined with CEUS can better distinguish between different pathological types of PCNs than can conventional ultrasound alone.

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Concerns about dioxin-like compounds have increased; however, the monitoring of polychlorinated naphthalenes (PCNs) in food and the assessment of dietary intake remain limited. In this study, various foods were collected from Korean markets and analyzed for PCNs. Fishery products exhibited the highest mean concentration (48.0 pg/g ww) and toxic equivalent (TEQ) (0.0185 pg-TEQ/g ww). Agricultural products were the largest contributors (35.7%) to the total dietary intake of PCNTEQ, followed by livestock products (33.6%), fishery products (20.2%), and processed foods (10.5%). The mean intake of PCNTEQ for the Korean population was 0.901 pg-TEQ/day for males and 0.601 pg-TEQ/day for females. Generally, males and younger groups had higher daily intakes of PCNTEQ, but they did not exceed the tolerable weekly intakes. Nonetheless, it is important to manage potential health risks associated with PCNs and other dioxin-like compounds by identifying major food items contributing to PCN exposure and considering age and gender differences.

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The structure of isolated 1-chloronaphthalene has been investigated in a supersonic expansion by high-resolution chirped-pulse Fourier transform microwave (CP-FTMW) spectroscopy in the 2-8 GHz frequency range. Accurate values of the rotational, centrifugal distortion, and nuclear quadrupole coupling constants for the only availabe conformer have been determined. The intensity of the spectrum allowed us to observe all the heavy atoms isotopologues in natural abundance, determining their rotational constants. From the extensive experimental dataset we derived accurate structures for 1-chloronaphthalene using different methodologies and compared with related compounds.

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Over the last two decades, Taiwan has effectively diminished atmospheric concentrations of polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) through the adept utilization of advanced technologies and the implementation of air pollution control devices. Despite this success, there exists a dearth of data regarding the levels of other PM2.5-bound organic pollutants and their associated health risks. To address this gap, our study comprehensively investigates the spatial and seasonal variations, potential sources, and health risks of PCDD/Fs, Polychlorinated biphenyls (PCBs), and Polychlorinated naphthalene (PCNs) in Northern and Central Taiwan. Sampling collections were conducted at three specific locations, including six municipal waste incinerators in Northern Taiwan, as well as a traffic and an industrial site in Central Taiwan. As a result, the highest mean values of PM2.5 (20.3-39.6 µg/m3) were observed at traffic sites, followed by industrial sites (14.4-39.3 µg/m3), and the vicinity of the municipal waste incinerator (12.4-29.4 µg/m3). Additionally, PCDD/Fs and PCBs exhibited discernible seasonal fluctuations, displaying higher concentrations in winter (7.53-11.9 and 0.09-0.12 fg I-TEQWHO/m3) and spring (7.02-13.7 and 0.11-0.16 fg I-TEQWHO/m3) compared to summer and autumn. Conversely, PCNs displayed no significant seasonal variations, with peak values observed in winter (0.05-0.10 fg I-TEQWHO/m3) and spring (0.03-0.08 fg I-TEQWHO/m3). Utilizing a Positive Matrix Factorization (PMF) model, sintering plants emerged as the predominant contributors to PCDD/Fs, constituting 77.9% of emissions. Woodchip boilers (68.3%) and municipal waste incinerators (21.0%) were identified as primary contributors to PCBs, while municipal waste incinerators (64.6%) along with a secondary copper and a copper sludge smelter (22.1%) were the principal sources of PCNs. Moreover, the study specified that individuals aged 19-70 in Northern Taiwan and those under the age of 12 years in Central Taiwan were found to have a significantly higher cancer risk, with values ranging from 9.26 x 10-9-1.12 x 10-7 and from 2.50 x 10-8-2.08 x 10-7respectively.

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EFSA was asked for a scientific opinion on the risks for animal and human health related to the presence of polychlorinated naphthalenes (PCNs) in feed and food. The assessment focused on hexaCNs due to very limited data on other PCN congeners. For hexaCNs in feed, 217 analytical results were used to estimate dietary exposures for food-producing and non-food-producing animals; however, a risk characterisation could not be performed because none of the toxicological studies allowed identification of reference points. The oral repeated dose toxicity studies performed in rats with a hexaCN mixture containing all 10 hexaCNs indicated that the critical target was the haematological system. A BMDL20 of 0.05 mg/kg body weight (bw) per day was identified for a considerable decrease in the platelet count. For hexaCNs in food, 2317 analytical results were used to estimate dietary exposures across dietary surveys and age groups. The highest exposure ranged from 0.91 to 29.8 pg/kg bw per day in general population and from 220 to 559 pg/kg bw per day for breast-fed infants with the highest consumption of breast milk. Applying a margin of exposure (MOE) approach, the estimated MOEs for the high dietary exposures ranged from 1,700,000 to 55,000,000 for the general population and from 90,000 to 230,000 for breast-fed infants with the highest consumption of breast milk. These MOEs are far above the minimum MOE of 2000 that does not raise a health concern. Taking account of the uncertainties affecting the assessment, the Panel concluded with at least 99% certainty that dietary exposure to hexaCNs does not raise a health concern for any of the population groups considered. Due to major limitations in the available data, no assessment was possible for genotoxic effects or for health risks of PCNs other than hexaCNs.

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Polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs), polychlorinated biphenyls (PCBs), and polychlorinated naphthalenes (PCNs) were assessed in coastal sediments from industrial bays in South Korea to evaluate the pollution levels and their environmental impact. The mean sediment concentrations of Σ17 PCDD/Fs, Σ18 PCBs, and Σ15 PCNs were 198 ± 140, 3427 ± 7037, and 85 ± 336 pg/g dw, respectively. Generally, pollutant concentrations in the inner bay were higher than those in the outer bay, indicating the influence of industrial emissions and harbor activities. The primary sources were identified as steel manufacturing and wastewater treatment plants for PCDD/Fs, harbor and shipbuilding activities for PCBs, and combustion-related sources for PCNs. Notably, PCDD/F concentrations exceeded sediment guideline values. The combined effects of PCDD/Fs and PCBs demonstrated adverse impacts on aquatic organisms. Hence, the release of toxic pollutants into the marine environment could have potential biological effects due to the combined impact of these various compounds.

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INTRODUCTION: Porous coordination networks (PCNs) have been widely used in large number of applications such as light harvesting, catalysis, and biomedical applications. Inserting porphyrins into PCNs scaffolds can alleviate the solubility and chemical stability problems associated with porphyrin ligands and add functionality to PCNs. The discovery that some PCNs materials have photosensitizer and acoustic sensitizer properties has attracted significant attention in the field of biomedicine, particularly in cancer therapy. This article describes the latest applications of the porphyrin ligand-based family of PCNs in cancer chemodynamic therapy (CDT), photodynamic therapy (PDT), sonodynamic therapy (SDT), photothermal therapy (PTT), and combination therapies and offers some observations and reflections on them. AREAS COVERED: This article discusses the use of the PCN family of MOFs in cancer treatment, specifically focusing on chemodynamic therapy, sonodynamic therapy, photodynamic therapy, photothermal therapy, and combination therapy. EXPERT OPINION: Although a large number of PCNs have been developed for use in novel cancer therapeutic approaches, further improvements are needed to advance the use of PCNs in the clinic. For example, the main mechanism of action of PCNs against cancer and the metabolic processes in organisms, and how to construct PCNs that maintain good stability in the complex environment of organisms.

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This review updates information on the historical manufacture and unintentional production of polychlorinated naphthalenes (PCNs). The direct toxicity of PCNs as a result of occupational human exposure and through contaminated feed in livestock was recognised decades ago, making PCNs a precursor chemical for consideration in occupational medicine and occupational safety. This was confirmed by the listing of PCNs by the Stockholm Convention as a persistent organic pollutant in the environment, food, animals and humans. PCNs were manufactured globally between 1910 ∼ 1980, but reliable data on the volumes produced or national outputs are scarce. A total figure for global production would be useful for the purposes of inventory and control and it is clear that combustion related sources such as waste incineration, industrial metallurgy and use of chlorine are current major sources of PCNs to the environment. The upper bound estimate of total global production has been put at 400,000 metric tons but the amounts (at least, many 10 s of tonnes) that are currently emitted unintentionally every year through industrial combustion processes should also be inventoried along with estimates for emissions from bush and forest fires. This would however require considerable national effort, financing and co-operation from source operators. The historical (1910-1970 s) production and resulting emissions through diffusive/evaporative releases through usage, are still reflected in documented occurrence and patterns of PCNs in human milk in Europe and other locations worldwide. More recently, PCN occurrence in human milk from Chinese provinces has been linked to local unintentional emissions from thermal processes.

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Polychlorinated naphthalenes (PCNs) are dioxin-like compounds that have been reported to be present in a wide variety of foodstuffs. Milk-based infant and toddler formula sometimes plays an important role in the diet of young children and could potentially cause adverse effects if contaminated with PCNs. This study investigated the concentrations of PCNs in commercial milk-based formula produced in different countries and sold on the Chinese market for three age groups: 0-6, 6-12 and 12-36 months. The total concentrations of PCNs in 72 samples from different countries of formula based on cow milk ranged from 7.8 to 30.3 pg/g whole weight (ww). Although the PCN concentrations in formula produced in Asia, Europe and South Pacific varied, all had comparable toxic equivalent (TEQ) values. Tri-CNs were the predominant PCN homologue in all samples. No significant differences in the concentrations of PCNs were found between samples of formula for each of the three age groups. The mean TEQ for PCNs in goat milk formula samples (0.0031 pg TEQ/g ww) was higher than the value for cow milk formula (0.0009 pg TEQ/g ww) produced in China, and the proportion of higher chlorinated PCNs in goat milk formula was also higher. Based on dry weight, the mean concentration of PCNs in the raw cow milk (119 pg/g dry weight (dw)) used to produce infant and toddler formula was higher than that in the actual formula (24.2 pg/g dw), and the PCN profiles also varied between the raw milk and formula. A risk assessment indicated that, in China, consuming formula poses a lower risk to infants and toddlers from based on exposure to PCNs compared with consuming breast milk.

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Polychlorinated naphthalenes (PCNs) are ubiquitous atmospheric pollutants that can even be found in the most remote region of the Arctic. However, temporal trend analysis and reports on mono- to octa-CN in the Arctic air are still scarce. In the present study, 8 years of atmospheric monitoring data of PCNs on Svalbard was investigated using XAD-2 resin passive air samplers (PASs) from 2011-2019. The concentrations of ∑75 PCNs in the Arctic air ranged from 4.56 to 85.2 pg/m3, with a mean of 23.5 pg/m3. The mono-CNs and di-CNs were the dominant homologue groups accounting for 80 % of the total concentrations. The most abundant congeners were PCN-1, PCN-2, PCN-24/14, PCN-5/7, and PCN-3, respectively. A declining time trend of PCN concentration was observed from 2013 to 2019. The reduction in PCN concentrations is likely due to declining global emissions and banned production. However, no significant spatial difference was observed among the sampling sites. The total PCN toxic equivalency (TEQ) concentrations in the Arctic atmosphere ranged from 0.043 to 1.93 fg TEQ/m3 (mean 0.41 fg TEQ/m3). The fraction of combustion-related congeners to ∑PCNs (tri- to octa-CN) analysis results indicated that the sources of PCNs in the Arctic air were contributed mainly from reemissions of historical Halowax mixtures and combustion-related sources. To the best of our knowledge, this is the first research to report all 75 PCN congeners and homologue groups in Arctic air. Therefore, this study provides data on recent temporal trend analysis as well as all the 75 PCN congeners in the Arctic atmosphere.

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Polychlorinated naphthalenes (PCNs) are produced from a variety of industrial sources, and they reach the aquatic ecosystems by the dry-wet deposition from the atmosphere and also by the drainage from the land surfaces. Then the PCNs can be transmitted through the food chain to humans and show toxic effects on different aquatic animals as well as humans. Considering this scenario, it is an obligatory task to explore the toxicity data of PCNs more deeply for the species of an aquatic ecosystem (green algae-Daphnia magna-fish), and to extrapolate those data for humans. But the toxicity data for different aquatic species are quite limited. The laboratory experimentations are complicated and ethically troublesome to fill toxicity data gaps; therefore, different in silico methods (e.g., QSAR, quantitative read-across predictions) are emerging as crucial ways to fill the data gaps and hazard assessments. In the present study, we developed individual toxicity models as well as interspecies models from the 75 PCN toxicity data against three aquatic species (green algae-Daphnia magna-fish) by employing easily interpretable 2D descriptors; these models were validated rigorously employing different globally accepted internal and external validation metrics. Then we interpreted the modelled descriptors mechanistically with the endpoint values for better understanding. And finally, we endeavored to improve the prediction quality in terms of external validation metrics by employing a novel quantitative read-across approach by pooling the descriptors from the developed individual QSAR models.

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We investigated the clinicopathological role of the PD-1/PD-L1 pathway in the primary diffuse large B-cell lymphoma of the central nervous system (PCNS-DLBCL). Standardized staining for PD-L1 was performed by machine staining, and internationally accepted interpretation methods were used. The PD-L1 immunostaining ≥ 20 % of all cells in slices was defined as high expression of PD-L1. CD4, CD8, and PD-1 tumor-infiltrating lymphocytes (TILs) were enumerated, and the median was defined as the cutoff value. Values higher than the median was defined as high expression. Thirty-four cases (64.2 %) showed high expression of PD-L1. PD-L1 expression was associated with a good prognosis when 20 % was considered as cutoff value and had the smallest P value. By contrast, a low number of CD8+ or PD-1+ TILs was associated with poor prognosis. Patients with low expression of PD-L1 had poor overall survival (P = 0.001), and those with increased CD8 or PD-1 TILs tended to have improved overall survival (P = 0.004 and 0.024, respectively). Low number of monocytes, increased number of lymphocytes, IPI score ≥ 2, ECOG PS ≥ 2, LDH ≥ 250, and Ki67 ≥ 70 % were independent prognostic factors for OS. In conclusion, PD-L1 expression, CD8 and PD-1 TILs, monocyte status, and ECOG PS might be prognostic markers and therapeutic targets of PCNS-DLBCL.

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Emerging pollutants (EPs) are chemical substances that are commonly not regulated and can be detected at low or very low concentrations. However, EPs have triggered special concern because their long-term adverse effects on the environment and human health remain unknown. Most EPs show biological toxicity, environmental persistence, and bioaccumulation. Even at low concentrations in the environment, EPs may pose significant environmental and health risks. Therefore, their treatment has been explicitly included in the 14th Five Year Plan for National Economic and Social Development of the People's Republic of China and the Outline of the Long-term Goals for 2035. Soil is a source of pollutants, and its quality is directly related to economic development, ecological security, and people's livelihood. At present, China's soil environmental monitoring system is not perfect, and the ability to monitor these new organic pollutants is lagging. Therefore, to strengthen the supervision of construction and agricultural land soil environments, it is essential to strengthen the soil environment monitoring ability for these EPs and establish a reliable, steady, and economic analysis method, including their separation and analysis methods in soil. Polychlorinated naphthalenes (PCNs) have received considerable attention as emerging halogenated compounds. They were listed in Annexes A and C of the Stockholm Convention on persistent organic pollutants (POPs) in 2015 because of their persistence, multimedia fate, and toxicity. PCNs have now been detected in the surrounding soils. Owing to their trace levels in complex soil, high requirements have been put forward for the pretreatment and instrument analysis of PCNs. This study aims to develop a new method for the selective purification of PCNs in soil, which can not only effectively remove lipids and other interferences in soil but also effectively reduce time, labor, and material costs in the pre-treatment process. Based on the physicochemical properties of the 13X molecular sieve, it was explored to purify soil-extracts as solid-phase extraction (SPE) sorbents. With n-hexane as the loading and rinsing solvent, 10 mL of a dichloromethane/n-hexane mixture (2∶15, v/v) was used to elute the PCNs. Moreover, selective separation of target substances from lipid macromolecules and other interferences could be achieved simultaneously. For the selective separation of PCNs, the average recovery of the internal standard could reach 56.1% to 88.0%. 13X molecular sieves are superior to gel permeation chromatography (GPC) and Florisil SPE, and they exhibit good cleanup efficiency similar to a multilayer silica gel/alumina column (53.0%-117.0%). Although the obtained recoveries are not as high as those obtained with a multilayer silica gel/alumina column, 13X molecular sieves have advantages in terms of simple operation, environmental friendliness, and low cost. Based on these fundamental experiments, accelerated solvent extraction was used to extract targets in soil, molecular sieves were used as SPE sorbents for purification, and GC-MS/MS was employed for PCN analysis. This method was developed as a systematic analytical method for PCNs determination. The method detection limits (MDLs) for PCN homologs were in the range of 0.009-0.6 ng/g. The precision and accuracy of the method were evaluated using spiked matrices. At three spiked levels (4, 10, and 18 ng), the recoveries of PCNs (CN-3, 13, 42, 46, 52, 53, 73, and 75) were 70%-128%, 71%-115%, and 61%-114%, respectively, and the corresponding relative standard derivations were 4.2%-23%, 6.5%-31% and 4.7%-22%. Thus, this method meets the requirements of trace analysis and shows acceptable parallelism, sensitivity, accuracy, and precision, thus being feasible for the analysis of emerging pollutant. The method is expected to play an important role in sample pretreatment in the future, especially for the nationwide investigation of soil pollution.

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The incidence of primary central nervous system lymphoma has increased over the past two decades in immunocompetent patients and the prognosis remains poor. A diagnosis and complete evaluation of the patient is needed without delay, but histologic evaluation is not always available and PCNSL can mimic a variety of brain lesions on MRI. In this article, we review the potential role of 18F-FDG PET for the diagnosis of PCNSL in immunocompetent and immunocompromised patients. Its contribution to systemic assessment at the time of diagnosis has been well established by expert societies over the past decade. In addition, 18F-FDG provides valuable information for differential diagnosis and outcome prediction. The literature also shows the potential role of 18F-FDG as a therapeutic evaluation tool during the treatment and the end of the treatment. Finally, we present several new radiotracers that may have a potential role in the management of PCNSL in the future.

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Polychlorinated naphthalenes (PCNs) have a structure similar to that of polychlorinated biphenyls (PCBs) and represent a new type of persistent organic pollutants (POPs) that are widely present in the environment and biological communities. PCNs can migrate and transform via different environmental media, which severely affects the health of humans and organisms. Researchers have devoted considerable focus on ambient air pollution. Although the current ambient air quality has not yet limited the concentration of PCNs, the Stockholm Convention has required parties to prohibit and eliminate their production and use. As one of the contracting parties, China is obligated to improve its environmental monitoring. In other words, the development of a method for monitoring PCNs in ambient air is important for understanding ambient air quality and safeguarding human health. PCNs are generally present at trace levels (pg/m3) in ambient air. To achieve accurate quantification of PCNs, high demands are raised on the methods for extraction, purification, and instrumental analysis, which can directly affect the efficiency, accuracy, and sensitivity of a method. Considering the trace-level presence of PCNs in ambient air and the high efficiency and accuracy of the analytical method, accelerated solvent extraction (ASE), combined with column chromatography using a multilayer silica gel column and a neutral alumina column, was established for the extraction and purification of PCNs in ambient air. The important parameters involved in the aforementioned steps, such as the type of extraction and volume of elution solvent, were optimized. The results indicated that dichloromethane-hexane (1∶1, v/v) was the best extraction solvent for the recovery of PCNs. Hexane and dichloromethane-hexane (5∶95, v/v) were used as the elution solvents for the multi-silica gel column and neutral alumina column, respectively. Isotope dilution gas chromatography-triple quadrupole mass spectrometry (GC-MS/MS) was used to quantify the target compounds. Gas chromatographic parameters, such as temperature program conditions and inlet temperature, were also optimized. The oven temperature program was as follows: 80 ℃ for 1 min, 80 ℃ to 160 ℃ at 15 ℃/min, 160 ℃ to 265 ℃ at 3 ℃/min, and 265 ℃ to 280 ℃ at 5 ℃/min, followed by holding the temperature at 280 ℃ for 10 min. The inlet temperature was set at 260 ℃. The optimal characteristics of ion pair, collision energy, and ion source temperature were determined by optimizing the key mass spectrometry parameters. The developed instrumental method, combined with suitable sample preparation techniques, was used to determine the concentrations of PCNs in ambient air samples. Quality control (QC) and quality assurance (QA) were performed by adding isotope internal standards before sampling, extraction, and injection analysis to monitor the entire analysis process. The relative standard deviations (RSDs) of the relative response factors (RRFs) for trichloronaphthalene to octachloronaphthalene were less than 16% in the concentration range of 2-100 ng/mL. The method detection limits (MDLs) for PCN homologues were in the range of 1-3 pg/m3(calculated using a sample volume of 288 m3). The precision and accuracy of this method for determining PCNs in ambient air samples were evaluated using a spiked matrix. The average spiked recoveries of trichloronaphthalene to octachloronaphthalene were 89.0%-119.4%, 98.6%-122.5% and 93.7%-124.5% at low, medium, and high spiked concentrations (20, 50, and 90 ng/mL), respectively. The RSDs of the assay results were 1.9%-7.0%, 1.6%-6.6%, and 1.0%-4.8%, respectively. During the entire analysis process, the average recoveries of the sampling and extracted internal standards were 136.2%-146.0% and 42.4%-78.1%, respectively, and the corresponding RSDs were 5.6%-7.5% and 2.7%-17.5%. Thus, this method meets the requirements of trace analysis and exhibits good parallelism, high sensitivity, high accuracy, and good precision, and it is suitable for the accurate quantitative determination of trichloronaphthalene to octachloronaphthalene in ambient air.

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This study explored the combined disruption mechanism of polychlorinated naphthalenes (PCNs) on the three key receptors (estrogen receptor, thyroid receptor, and adrenoceptor) of the human endocrine system. The intensity of PCN endocrine disruption on these receptors was first determined using a molecular docking method. A comprehensive index of PCN endocrine disruption to human was quantified by analytic hierarchy process and fuzzy analysis. The mode of action between PCNs and the receptors was further identified to screen the molecular characteristics influencing PCN endocrine disruption through molecular docking and fractional factorial design. Quantitative structure-activity relationship (QSAR) models were established to investigate the toxic mechanism due to PCN endocrine disruption. The results showed that the lowest occupied orbital energy (ELUMO) was the most important factor contributing to the toxicity of PCNs on the endocrine receptors, followed by the orbital energy difference (ΔE) and positive Millikan charge (q+). Furthermore, the strategies were formulated through adjusting the nutritious diet to reduce health risk for the workers in PCN contaminated sites and the effectiveness and feasibility were assessed by molecular dynamic simulation. The simulation results indicated that the human health risk caused by PCN endocrine disruption could be effectively decreased by nutritional supplementation. The binding ability between PCNs and endocrine receptors significantly declined (up to -16.45%) with the supplementation of vitamins (A, B2, B12, C, and E) and carotene. This study provided the new insights to reveal the toxic mechanism of PCNs on human endocrine systems and the recommendations on nutritional supplements for health risk reduction. The methodology and findings could serve as valuable references for screening of potential endocrine disruptors and developing appropriate strategies for PCN or other persistent organic pollution control and health risk management.

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Although the probability of pancreatic cystic neoplasms (PCNs) being detected is raising year by year, their differential diagnosis and individualized treatment are still a challenge in clinical work. PCNs are tumors containing cystic components with different biological behaviors, and their clinical manifestations, epidemiology, imaging features, and malignant risks are different. Some are benign [e.g., serous cystic neoplasms (SCNs)], with a barely possible that turning into malignant, while others display a low or higher malignant risk [e.g., solid pseudopapillary neoplasms (SPNs), intraductal papillary mucinous neoplasms (IPMNs), and mucinous cystic neoplasms (MCNs)]. PCN management should concentrate on preventing the progression of malignant tumors while preventing complications caused by unnecessary surgical intervention. Clinically, various advanced imaging equipment are usually combined to obtain a more reliable preoperative diagnosis. The challenge for clinicians and radiologists is how to accurately diagnose PCNs before surgery so that corresponding surgical methods and follow-up strategies can be developed or not, as appropriate. The objective of this review is to sum up the clinical features, imaging findings and management of the most common PCNs according to the classic literature and latest guidelines.

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IMPORTANCE: Neurological and neuropsychiatric symptoms that persist or develop three months after the onset of COVID-19 pose a significant threat to the global healthcare system. These symptoms are yet to be synthesized and quantified via meta-analysis. OBJECTIVE: To determine the prevalence of neurological and neuropsychiatric symptoms reported 12 weeks (3 months) or more after acute COVID-19 onset in adults. DATA SOURCES: A systematic search of PubMed, EMBASE, Web of Science, Google Scholar and Scopus was conducted for studies published between January 1st, 2020 and August 1st, 2021. The systematic review was guided by Preferred Reporting Items for Systematic Review and Meta-Analyses. STUDY SELECTION: Studies were included if the length of follow-up satisfied the National Institute for Healthcare Excellence (NICE) definition of post-COVID-19 syndrome (symptoms that develop or persist ≥3 months after the onset of COVID-19). Additional criteria included the reporting of neurological or neuropsychiatric symptoms in individuals with COVID-19. DATA EXTRACTION AND SYNTHESIS: Two authors independently extracted data on patient characteristics, hospital and/or ICU admission, acute-phase COVID-19 symptoms, length of follow-up, and neurological and neuropsychiatric symptoms. MAIN OUTCOME(S) AND MEASURE(S): The primary outcome was the prevalence of neurological and neuropsychiatric symptoms reported ≥3 months post onset of COVID-19. We also compared post-COVID-19 syndrome in hospitalised vs. non-hospitalised patients, with vs. without ICU admission during the acute phase of infection, and with mid-term (3 to 6 months) and long-term (>6 months) follow-up. RESULTS: Of 1458 articles, 19 studies, encompassing a total of 11,324 patients, were analysed. Overall prevalence for neurological post-COVID-19 symptoms were: fatigue (37%, 95% CI: 24%-50%), brain fog (32%, 9%-55%), memory issues (27%, 18%-36%), attention disorder (22%, 10%-34%), myalgia (18%, 4%-32%), anosmia (12%, 7%-17%), dysgeusia (11%, 4%-17%) and headache (10%, 1%-21%). Neuropsychiatric conditions included sleep disturbances (31%, 18%-43%), anxiety (23%, 13%-33%) and depression (12%, 7%-21%). Neuropsychiatric symptoms substantially increased in prevalence between mid- and long-term follow-up. Compared to non-hospitalised patients, patients hospitalised for acute COVID-19 had reduced frequency of anosmia, anxiety, depression, dysgeusia, fatigue, headache, myalgia, and sleep disturbance at three (or more) months post-infection. Conversely, hospital admission was associated with higher frequency of memory issues (OR: 1.9, 95% CI: 1.4-2.3). Cohorts with >20% of patients admitted to the ICU during acute COVID-19 experienced higher prevalence of fatigue, anxiety, depression, and sleep disturbances than cohorts with <20% of ICU admission. CONCLUSIONS AND RELEVANCE: Fatigue, cognitive dysfunction (brain fog, memory issues, attention disorder) and sleep disturbances appear to be key features of post-COVID-19 syndrome. Psychiatric manifestations (sleep disturbances, anxiety, and depression) are common and increase significantly in prevalence over time. Randomised controlled trials are necessary to develop intervention strategy to reduce disease burden.

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