Environmental exposure and ecological risk of perfluorinated substances (PFASs) in the Shaying River Basin, China

There have been concerns raised about the environmental effects of perfluoroalkyl substances (PFASs) because of their toxicity, widespread distribution, and persistence. Understanding the occurrences and ecological risk posed by PFASs is essential, especially for the short-chain replacements perfluorobutanoic acid (PFBA) and perfluorobutane sulfonic acid (PFBS), which are now becoming predominant PFASs. The lack of aquatic life criteria (ALC), however, prevents an accurate assessment of the ecological risks of PFBA and PFBS. This study thus investigated the occurrence of 15 PFASs at 29 sampling sites in Shaying River Basin (in China) systematically, conducted the toxicity tests of PFBA and PFBS on eight resident aquatic organisms in China, and derived the predicted non-effect concentration (PNEC) values for PFBA and PFBS for two environmental media in China. The results showed that the total PFASs concentrations (ΣPFASs) ranged from 5.07 to 20.32 ng/L (average of 10.95 ng/L) in surface water, whereas in sediment, ΣPFASs ranged from 6.46 to 20.05 ng/g (dw) (average of 11.51 ng/g). The presence of PFBS was the most prominent PFASs in both water (0.372-8.194 ng/L) and sediment (4.54-15.72 ng/g), demonstrating that short-chain substitution effects can be observed in watersheds. The PNEC values for freshwater and sediment were 6.60 mg/L and 8.30 mg/kg (ww), respectively, for PFBA, and 14.04 mg/L, 37.08 mg/kg (ww), respectively, for PFBS. Ecological risk assessment of two long-chain PFASs, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), and two short-chain PFASs, PFBA and PFBS, using the hazard quotient method revealed that Shaying River and other major River Basins in China were at risk of PFOS contamination. This study contributes to a better understanding of the presence and risk of PFASs in the Shaying River and first proposes the ALCs for PFBA and PFBS in China, which could provide important reference information for water quality standards.

Water quality criteria and ecological risk assessment for ammonia in the Shaying River Basin, China

Current Chinese surface water environmental quality standard GB3838-2002 for ammonia fails to take water quality factors and native organism distributions in different basins into consideration. In this study, ammonia toxicity tests were performed using three aquatic organisms native to the Shaying River Basin (China). Published ammonia toxicity data with pH and temperature, and toxicity data acquired in this study were used to establish water quality criteria. The final criterion maximum concentration (CMC) and criterion continuous concentration (CCC) for the Shaying River Basin were 5.09 and 1.36 (mg total ammonia nitrogen (TAN))/L (pH 7 and 20 °C), respectively. In addition, based on the corresponding relationship between ammonia toxicity and temperature and pH, the ecological risk assessment of ammonia was conducted in different seasons for the Shaying River using a tiered approach of both hazard quotient (HQ) and the joint probability (JPC) methods. Two methods gave consistent results: the ecological risks of ammonia to aquatic species in the Shaying River Basin were severe and the risk could be ranked as wet season > flat season > dry season. It is therefore indicating that monitoring, evaluation, and early warning of ammonia pollution need to be taken to prevent and control the risks posed by ammonia pollution, especially for wet season (because of high temperatures and pH) or flat season (because of high pH values). We hope the present work could provide valuable information to manage and control ammonia pollution in the Shaying River Basin.

MicroRNA-145 plays a role in mitochondrial dysfunction in alveolar epithelial cells in lipopolysaccharide-induced acute respiratory distress syndrome

BACKGROUND

Acute respiratory distress syndrome (ARDS) causes substantial mortalities. Alveolar epithelium is one of the main sites of cell injuries in ARDS. As an important kind of microRNAs (miRNAs), microRNA-145 (miR-145) has been studied in various diseases, while its role in ARDS has not been investigated.

METHODS

Lipopolysaccharide (LPS) was intratracheally instilled to establish a rat ARDS model. Cytokines from bronchoalveolar lavage fluid (BALF) were measured using rat tumor necrosis factor-α and interleukin-6 enzyme-linked immunosorbent assay kits (R&D Systems), and the pathological structures were evaluated using hematoxylin and eosin (H&E) staining and transmission electron microscope; the lung miR-145 messenger RNA (mRNA) was detected using quantitative polymerase chain reaction. Bioinformatics focused on the target genes and possible pathways of gene regulation.

RESULTS

A rat model of LPS-induced ARDS was successfully established. The miR-145 was down-regulated in the LPS-induced ARDS lung, and mitochondrial dysfunction was observed in alveolar epithelial cells, most obviously at 72 hours after LPS. TargetScan and miRDB databases were used to predict the target genes of miR-145. A total of 428 overlapping genes were identified, seven genes were associated with mitochondrial function, and Ogt, Camk2d, Slc8a3, and Slc25a25 were verified. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were enriched in the mitogen-activated protein kinase (MAPK) signaling pathway, and Gene Ontology (GO) biological process was mainly enriched in signal transduction and transcription regulation.

CONCLUSIONS

The miR-145 is down-regulated in LPS-induced ARDS, and affects its downstream genes targeting mitochondrial functions.

[Sources and Ecological Risk Assessment of Polycyclic Aromatic Hydrocarbons in the Jiaxing River Network]

In order to study the pollution source and ecological risk assessment of polycyclic aromatic hydrocarbons (PAHs) in the Jiaxing river network, PAHs were analyzed by GC-MS. The results show that with the influence of rainfall and surface runoff in the wet season, the types and mass concentrations of PAHs in the river network of Jiaxing differ from the dry season. Ten and 16 priority PAHs were detected in the dry season and wet season, respectively. The average mass concentration of PAHs in the dry season was 143.83ng·L^-1 and 73.47ng·L^-1 in the wet season. The range of mass concentration of PAHs in the dry and wet season was 77.32-283.76ng·L^-1 and 13.05-133.02ng·L^-1, respectively, and 2-ring and 3-ring PAHs accounted for 79.18% in the dry season and 73.60% in the wet season. PAHs pollution in the river network of Jiaxing was at a low level compared with the domestic and foreign areas. The isomer ratio and principal component analysis found that the PAHs in the Jiaxing river network mainly come from urban non-point source pollution, combustion source, and traffic pollution in the dry season and wet season. The results of the Kalf risk entropy method show that in the dry season, naphthalene(Nap), acenaphthylene(Acy), acenaphthene(Ace), fluorene(Flu), phenanthrene(Phe), anthracene(Ant), fluoranthene(Fla), pyrene(Pyr), and benzo(a)anthracene(BaA) are at moderate ecological risk. In the wet season, Nap, Acy, Flu, Phe, Fla, Pyr, BaA, benzo(b)fluoranthene(BbF), benzo(k)fluoranthene(BkF), benzo(a)pyrene(BaP), indeno(1,2,3-cd)pyrene(InP), and benzo(g,h,i)perylene(BghiP) are at moderate ecological risk. In the dry season, ∑PAHs are at moderate ecological risk, and low in the wet season. On the whole, PAHs pollution in the Jiaxing river network presents moderate ecological risk levels, and measures to reduce the ecological risk of PAHs in the river network should be taken by the Departments concerned.

Giant gastroduodenal trichobezoar: A case report

BACKGROUND

We report a case of giant gastroduodenal trichobezoar, an extremely rare upper gastrointestinal bezoar due to trichotillomania and trichophagia.

CASE SUMMARY

The patient was a 10-year-old girl who presented with an abdominal mass that was discovered at palpation and noninvasive imaging examinations. Computed tomography (CT) showed a well-circumscribed heterogeneous mass extending from the stomach into the duodenum. The patient underwent a laparotomy to pull out the trichobezoar. Although these imaging findings are nonspecific, trichobezoar should be included in the differential diagnosis of gastric mass, especially with the history of an irresistible urge to pull out and swallow their hair.

CONCLUSION

Laparotomy is useful and practical for the management of giant gastroduodenal trichobezoar.

Deriving water quality criteria for China for the organophosphorus pesticides dichlorvos and malathion

Organophosphorus pesticides are effective, cheap, and used extensively but can harm aquatic organism and human health. Here, water quality criteria (WQCs) for dichlorvos (DDVP) and malathion (MAL) were derived. Nine aquatic organisms native to China were used in toxicity tests. Published toxicity data for aquatic organisms native and non-native to China were also analyzed. DDVP and MAL WQCs were derived using (log-normal model) species sensitivity distributions. Species sensitivity distribution curves indicated native and non-native species have different sensitivities to DDVP. The sensitivities of native and non-native species to MAL were not different because non-native species data for fewer than eight genera were available, so further research is required. The results indicated that native species need to be considered when deriving WQCs. The criteria maximum concentration (CMC) and criteria continuous concentration (CCC) were 1.33 and 0.132 μg/L, respectively, for DDVP, and 0.100 and 0.008 μg/L, respectively, for MAL. The CMCs for DDVP and MAL derived using ETX 2.0 software and species sensitivity ranks were different from the CMCs obtained using the SSD method because of parameter uncertainties. The DDVP and MAL WQCs were significantly lower than Chinese surface water quality standard thresholds. The results provide basic data for revising these thresholds.

Diabetes mellitus affects the biomechanical function of the callus and the expression of TGF-beta1 and BMP2 in an early stage of fracture healing

Transforming growth factor beta 1 (TGF-β1) and bone morphogenetic protein-2 (BMP-2) are important regulators of bone repair and regeneration. In this study, we examined whether TGF-β1 and BMP-2 expressions were delayed during bone healing in type 1 diabetes mellitus. Tibial fractures were created in 95 diabetic and 95 control adult male Wistar rats of 10 weeks of age. At 1, 2, 3, 4, and 5 weeks after fracture induction, five rats were sacrificed from each group. The expressions of TGF-β1 and BMP2 in the fractured tibias were measured by immunohistochemistry and quantitative reverse-transcription polymerase chain reaction, weekly for the first 5 weeks post-fracture. Mechanical parameters (bending rigidity, torsional rigidity, destruction torque) of the healing bones were also assessed at 3, 4, and 5 weeks post-fracture, after the rats were sacrificed. The bending rigidity, torsional rigidity and destruction torque of the two groups increased continuously during the healing process. The diabetes group had lower mean values for bending rigidity, torsional rigidity and destruction torque compared with the control group (P<0.05). TGF-β1 and BMP-2 expression were significantly lower (P<0.05) in the control group than in the diabetes group at postoperative weeks 1, 2, and 3. Peak levels of TGF-β1 and BMP-2 expression were delayed by 1 week in the diabetes group compared with the control group. Our results demonstrate that there was a delayed recovery in the biomechanical function of the fractured bones in diabetic rats. This delay may be associated with a delayed expression of the growth factors TGF-β1 and BMP-2.

Effect of hepatocyte growth factor encapsulated in targeted liposomes on liver cirrhosis

Hepatocyte growth factor (HGF) was encapsulated into sterically stabilized liposomes (SSL) in order to protect it from in vivo degradation. Cyclic Arg-Gly-Asp (RGD) peptides were combined with maleimide-[poly (ethylene glycol)]-1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (MAL-PEG-DOPE) incorporated into SSL. The average percentage of HGF encapsulated into liposomes was 32.38%, the size of liposomes was 91.56 nm and the polydispersity index was 0.164. In vivo, histological observation of the rat livers revealed that injection of RGD-SSL-HGF induced more significant remission of liver cirrhosis than injection of SSL-HGF, HGF alone, HGF plus RGD-SSL and saline. When the histological score, the collagen surface density, the hydroxyproline content and the expression of procollagen alpha1 (I) and alpha1 (III) mRNA in the liver were evaluated, all values were smallest in the RGD-SSL-HGF group. In contrast, an increase in apoptotic alpha-SMA-positive cells was noted in the RGD-SSL-HGF group. Together, this data suggests that targeted liposomes encapsulating HGF is a promising therapeutic modality in terms of promoting the remission of liver cirrhosis by promoting collagen fiber digestion, inhibiting collagen production, and promoting apoptosis of alpha-SMA-positive cells in rats with cirrhosis.

Cyclic Arg-Gly-Asp peptide-labeled liposomes for targeting drug therapy of hepatic fibrosis in rats

Targeting hepatic stellate cells (HSCs) has been challenging due to the lack of specific receptors or motifs on the cells. The aim of the present study was to develop a HSC-specific system for improving drug delivery to HSCs. The affinity of a cyclic peptide containing Arg-Gly-Asp (cRGD) to collagen type VI receptor on HSCs was examined in both in vitro and in vivo experiments. Sterically stable liposomes (SSLs) were modified with this peptide to yield a new carrier, cRGD-SSL. The targeting efficiency of this carrier in delivering interferon (IFN)-alpha1b was investigated in a rat model of liver fibrosis induced by bile duct ligation (BDL). When incubating HSCs or hepatocytes with cyclic RGD peptide, the peptide was bound preferentially to activated HSCs. Biodistribution study showed that the accumulation of cRGD peptide-labeled liposomes in HSCs isolated from BDL rats was 10-fold more than unlabeled SSLs. BDL rats receiving injections of IFN-alpha1b entrapped in cRGD-SSL exhibited significantly reduced extent of liver fibrosis compared with BDL control rats or BDL rats treated with IFN-alpha1b entrapped in SSLs. Thus, cRGD-SSL is an efficient drug carrier, which selectively targets activated HSCs and improves drug therapy for liver fibrosis to a significant extent. This liposomal formulation represents a new means of targeting drug carrier for the treatment of liver fibrosis, and it may have potential clinical applications.

Mutation spectrum and polymorphisms in ATP7B identified on direct sequencing of all exons in Chinese Han and Hui ethnic patients with Wilson's disease

Wilson's disease (WD), an autosomal recessive copper transport disorder, usually presents with symptoms involving the liver or central nervous system. The disease is caused by a large number of mutations in the ATP7B gene comprising 21 expressed exons. Some of the mutations appear to be population specific, whereas others are found in probands from a variety of different ethnic backgrounds. This paper presents the results of screening of the ATP7B gene by means of the direct sequencing of all exons in the gene in 39 Han and one Hui ethnic Chinese patients. Nineteen novel mutations were revealed along with nine others that have been previously described; 57.5% of the mutations were located in exons 8, 13, and 12. In particular, the Arg778Leu mutation in exon 8 was found in 55% of these Chinese patients in at least one allele. Five patients were homozygotes and 17 patients were heterozygotes for Arg778Leu. The detection rate on direct sequencing of the polymerase chain reaction products of all exons of the ATP7B gene in 40 unrelated patients was 83.8% of alleles. Seventeen polymorphisms were also identified in patients and healthy controls. We first reported the presence of ATP7B mutations in Chinese Hui ethnic patients and summarize our results here along with the previously reported findings. A significant correlation between genotype and phenotype was not found in 37 homozygotes and 52 heterozygotes for Arg778Leu.

Vasopressin-induced amber-like skin necrosis

Case reports about vasopressin-induced cutaneous necrosis are not frequent. Here we report a further case, of which skin manifestations included not only mottling, cyanosis, ecchymosis, bullae and gangrene, but also amber-like change in focal areas. Besides, intermittent paling of the skin with or without deep pain sensation of the limbs over non-injection sites was observed that might be a warning sign of impending skin necrosis. Based on the literature about vasopressin-induced skin necrosis we discuss the possible role of coagulation enhancement of this molecule.