Ecotoxicological risk of antibiotics and their mixtures to aquatic biota with the DGT technique in sediments.

Antibiotics are emerging contaminants and widely used in human healthcare, livestock, and aquaculture. The toxicity posed by antibiotics and their mixtures in sediments depends on their bioavailability. Now, the bioavailability of organic materials can be determined accurately by the diffusive gradients in thin films (DGT) technique. This technique was used for the first time ever in this study to evaluate in detail the integral toxicity of antibiotics in sediments to aquatic biota. Zhelin Bay was selected as a case study, because it is the largest mariculture area in eastern Guangdong, South China. Two antibiotics, chlortetracycline (CTC) (A) and sulfachlorpyridazine (SCP), were detected at average concentrations of 2.83 and 1.14 ng/ml, respectively. The other fifteen antibiotics were undetectable. The single risk assessment based on the risk quotient (RQ) of CTC and SCP shows that a relatively low risk has occurred. After this careful assessment of probabilistic ecotoxicological risks, the combined toxicity of antibiotic mixtures (CTC and SCP) clearly indicates that the toxicity probability of surface sediments to aquatic organisms was relatively low (0.23%).

A new method for estimating sedimental integrated toxicity of heavy metal mixtures to aquatic biota: a case study.

The existing methods of measuring combined toxicity of heavy metal mixtures in environment do not fully consider three major factors (i.e., number of heavy metal species, aquatic biota, all investigated sites as an entity). Herein, a new method named joint probabilistic risk (JPR) method is proposed for evaluating the combined toxicity of heavy metal mixtures to aquatic biota. In this new method, the above three factors are fully taken into account. In order to evaluate the feasibility of the new method, the Pearl River Estuary (PRE) is selected as a case study. Concentrations of heavy metals (Cd, Pb, Cr, Ni, Cu, and Zn) in surface sediments of PRE are investigated and toxic equivalent factors (TEFs) of these heavy metals are calculated. Based on TEFs, sedimental concentrations of heavy metals of PRE are converted to Cd toxic equivalent concentration (Cdeq), while the Cd toxicity data (Cdto) are extracted from the literature. The probability density curves for Cdeq and Cdto are constructed and the overlap area is quantified as 0.2497. This indicates that the surface sediments of PRE have a 24.97% probability of toxic effect towards aquatic biota. Finally, this new method is validated by two indirect methods of mERMq and mPELq.

Nonmetric multidimensional scaling and adverse effects on aquatic biota of polycyclic aromatic hydrocarbons in sediments: A case study of a typical aquaculture wetland, China.

Aquaculture wetlands, particularly those located within urban areas, are fragile ecosystems which are generally heavily impacted by urban and aquaculture activities. However, there are, to date, no reports on adverse effects related to polycyclic aromatic hydrocarbons (PAHs) in sediments from aquaculture wetlands in metropolitan areas. The characterization, sources, and incidence of adverse effects on aquatic biota of PAHs were studied in the riverine and estuarine sediments of the Rongjiang River in an aquaculture wetland in Chaoshan metropolis. The total PAH concentrations varied from 46.0 to 1665.2 ng/g (dry weight), with a mean of 246.4 ng/g, indicating lower concentrations than those of other comparable rivers and estuaries worldwide. High-molecular-weight PAHs were the major PAH species, with fluorene, benzo(b)fluoranthene, and benzo(a)pyrene as the dominant components. These PAHs are likely to be mainly derived from oil and coal/biomass combustion. Probability risk assessment indicated a moderate PAH ecological risk in the Rongjiang River and its estuary (RJE). Accordingly, a comprehensive management plan should be established to ensure sustainable aquaculture wetlands.

Bioaccessibilities and health implications of heavy metals in exposed-lawn soils from 28 urban parks in the megacity Guangzhou inferred from an in vitro physiologically-based extraction test.

This study focused on characterizing the oral bioaccessibilities and human health risks of eight heavy metals (Cd, Pb, Cr, Ni, Cu, Zn, Fe, and Mn) in surface-exposed lawn soils from 28 urban parks in Guangzhou. The physiologically-based extraction test (PBET) method was used to assess bioavailability (in gastric and intestinal phases) and human health risk was assessed via statistical modelling (carcinogenic risk assessment, hazard quotients and hazard indices). Mean bioaccessibilities of Cd, Pb, Cr, Ni, Cu, Zn, Fe, and Mn from all soil samples were 50.90 ± 17.67%, 5.81 ± 1.67%, 7.12 ± 3.24%, 17.91 ± 18.34%, 11.93 ± 2.88%, 34.33 ± 10.02%, 1.68 ± 0.48%, 26.71 ± 5.06%, respectively. The concentrations of most heavy metals were higher in the gastric phase, except for Cr and Ni which remained higher in the intestinal phase. Principal component analysis revealed that the bioaccessibilities of the heavy metals could be split into three groupings, based on the urban park of soil origin. The carcinogenic risk probabilities for Pb and Cr were under the acceptable level (< 1 × 10-4) for both adults and children. The hazard quotient and hazard index values indicated no significant risk of non-carcinogenic effects to children or adults exposed to Guangzhou urban park soils. This research will help inform further risk assessment and management of heavy metal contaminants in urban environments.

Case report: Rapidly progressive desmoid tumor after surgery for esophagogastric junction cancer and slowly progressive primary desmoid tumor: a report of two cases and literature review.

Background: Desmoid tumor (DT) is a rare locally aggressive but non-metastatic mesenchymal soft tissue neoplasm that predominantly occurs in the abdominal wall, abdominal cavity, and extremities. Its occurrence in the mesentery is relatively uncommon. Case reports: This article reports two cases of desmoid tumor treated at the Department of Gastrointestinal Surgery, Weifang People's Hospital. The first case was a 59-year-old male patient who had previously undergone surgery for esophagogastric junction cancer. Postoperatively, he developed an intra-abdominal mass that rapidly increased in size within three months. The second case was a 60-year-old male patient who incidentally discovered a mass in the left lower abdomen. Both patients underwent surgical treatment, and the postoperative pathological diagnosis was mesenteric desmoid tumor. Conclusion: The treatment of desmoid tumor remains challenging. Simple surgical resection often yields unsatisfactory outcomes, and the efficacy of adjuvant radiotherapy and chemotherapy is also limited. Further research and clinical practice are necessary to improve diagnostic and therapeutic strategies, aiming to enhance patient survival and quality of life.

Di-µ(2)-acetato-di-µ(2)-azido-di-µ(3)-methanol-tetra-kis-{µ-2-[(2-methyl-1-oxidopropan-2-yl)imino-meth-yl]-6-meth-oxy-phenolato}tetra-nickel(II) methanol disolvate.

In the centrosymmetric tetra-nuclear title complex, [Ni(4)(C(12)H(15)NO(3))(2)(CH(3)COO)(2)(N(3))(2)(CH(3)OH)(2)]·2CH(3)OH, the asymmetric unit comprises half of a complex mol-ecule and a methanol solvent mol-ecule. The Ni(II) ions display two different coordination environments: (i) two O atoms from the Schiff base ligand, two O atoms from symmetry-related methanol mol-ecules and an O atom from an acetate group, one N atom from the azide group, and (ii) two O atoms and one N atom from the Schiff base, one O atom from methanol, one O atom from the acetate anion, and one N atom from the azide group. Four coplanar Ni(II) ions are connected by two µ(2)-bridging O atoms from the two deprotonated Schiff bases, two µ(3)-O atoms from methanol mol-ecules, two µ(1,1)-N atoms from two azide ions, and four O atoms from acetate groups. The shortest Ni⋯Ni distance in the tetra-nuclear unit is 2.962 (2) Å. O-H⋯O hydrogen bonds between the methanol solvent mol-ecule and an acetate O atom feature in the crystal packing.

Role of carbon nanotracers in lymph node dissection of advanced gastric cancer and the selection of preoperative labeling time.

BACKGROUND: The incidence of gastric cancer is high. The number of dissected lymph nodes was an independent factor affecting prognosis. Although preoperative labeling is helpful in lymph nodes resection, there are no guidelines for when to perform preoperative labeling. AIM: To investigate the role of nanocarbon in lymph node dissection during gastrectomy, and to discuss the relationship between the timing of preoperative injection of carbon nanoparticles and the extent of lymph node dissection. METHODS: A prospective analysis was performed on the clinical data of 307 patients with advanced gastric cancer who underwent laparoscopic surgery in the General Surgery Department of Weifang People's Hospital between June 2018 and February 2021. The patients were randomly divided into experimental group and control group based on whether they received preoperative nanocarbon injection or not. The experimental group was divided into different groups according to the preoperative labeling time. The number of dissected lymph nodes and the number of lymph nodes with black staining were compared in each group after surgery, and the role of nanocarbon in the number of dissected lymph nodes, pathological staging, and the relationship with prognosis were discussed. RESULTS: The average number of dissected lymph nodes in the experimental group was higher than that in the control group. In the experimental group, the number of lymph node dissections and number of black-staining lymph nodes in the nanocarbon-labeling group at 2 d and 1 d before surgery were higher than in the labeling group on the day before surgery (P < 0.05). CONCLUSION: Preoperative nanocarbon labeling can safely and effectively guide lymph node dissection. To improve the detection rate of lymph nodes is conducive to subsequent comprehensive anti-tumor therapy.

Risk assessment of heavy metal and pesticide mixtures in aquatic biota using the DGT technique in sediments.

Heavy metals and pesticides (HMPs) are common contaminants due to their extensive use worldwide. Diffusive gradients in thin films (DGT) are a good method for measuring the bioavailable concentration of pollutants. This study represents the first evaluation of HMP toxicity in aquatic biota using the DGT technique in sediments. Zhelin Bay was selected as the case study site because it has been contaminated by pollutants. Nonmetric multidimensional scaling (NMS) analysis reveals that a diverse range of pollutants (V, Cr, Ni, Cu, Zn, As, Se, InHg, Mo, Cd, Sb, W, Pb, CLP, PYR) are mainly influenced by sediment characteristics. Assessment of single HMP toxicity found that the risk quotient (RQ) values for Mn, Cu, inorganic Hg (InHg), chlorpyrifos (CLP) and diuron (DIU) are significantly higher than 1, indicating that the adverse effects of these single HMPs should not be ignored. The combined toxicity of HMP mixtures based on probabilistic ecotoxicological risk assessment shows that Zhelin Bay surface sediments had a medium probability (54.6%) of toxic effects to aquatic biota.

First attempt to assess ecotoxicological risk of fifteen rare earth elements and their mixtures in sediments with diffusive gradients in thin films.

Rare earth elements (REEs) are emerging contaminants due to their large scale of exploitation worldwide for using in the high-technology sector. Diffusive gradients in thin films (DGT) are a good method to measure the bioaccessibility of inorganic substances. This study is the first to evaluate the combined toxicity of REEs in sediments to aquatic biota using the DGT technique. The intertidal zone of the Pearl River Estuary (PRE) was selected as a case study, as the upper reaches of the Pearl River is a major REE reserve and production region. The DGT-labile measured concentrations of REEs (∑REEs) were found to range from 7.02-16.06 µg/L in intertidal surface sediments of the PRE. Assessment of single REE toxicity found that risk quotient (RQ) values for Y, Pr, Nd, Eu, Dy, Er, and Yb are significantly higher than 1, indicating that the adverse effects of these single REEs should be not ignored. The combined toxicity of REE mixtures based on probabilistic ecotoxicological risk assessment, shows that intertidal surface sediments of PRE had a low probability (3.72%) of toxic effects to aquatic biota.

An unconstrained ordination- and GIS-based approach for identifying anthropogenic sources of heavy metal pollution in marine sediments.

A new method consisting of enrichment factor (EF) determination, nonmetric multidimensional scaling (NMS), and the geographic information system (GIS) technique was firstly developed to identify anthropogenic heavy metal sources in marine sediments of Hong Kong. Firstly, the EF was determined to differentiate between heavy metals originating from human and natural sources. Subsequently, NMS was applied to identify various source patterns of heavy metals, and the NMS score was calculated and spatially interpolated using GIS technology to evaluate the spatial influences of anthropogenic impacts in different areas. The concentrations of heavy metals in sediments of Hong Kong substantially exceeded their background values, demonstrating anthropogenic pollution. Two different types of human sources could be identified via NMS, one representing the industrial pollution discharges in the period from the 1960s to the 1980s before pollution control was introduced and one representing sewage discharge before the Tolo Harbour Action Plan in the mid-1980s.

Beryllium in riverine/estuarine sediments from a typical aquaculture wetland, China: Bioavailability and probabilistic ecological risk.

Beryllium (Be) is of a significant concern because of its mutagenic and carcinogenic properties. However, reports on presences of Be in sediments from aquaculture areas still remain unknown. This study investigated the total concentration and bioavailability of Be in the surface sediments from Rongjiang River and its estuary in a large-scale aquaculture wetland in Chaoshan metropolis, South China; together with its probabilistic ecological risks posed to aquatic organisms. The total and bioavailable concentrations of Be were in the range of 5.11-8.02 and 0.23-0.33 mg/kg, respectively. Total concentration of Be mainly originated from anthropogenic source and bioavailable Be was <6% of the total concentration of Be. The probabilistic ecological risk assessment based on bioavailable concentration of Be showed that surface sediments of Rongjiang River and its estuary had a low (2.91%) probability of toxic effect to aquatic organisms.