Spatially Confined Radical Addition Reaction for Electrochemical Synthesis of Carboxylated Graphene and its Applications in Water Desalination and Splitting.

Due to the chemical stability of graphene, synthesis of carboxylated graphene still remains challenging during the electrochemical exfoliation of graphite. In this work, a spatially confined radical addition reaction which occurs in the sub-nanometer scaled interlayers of the expanded graphene sheets for the electrochemical synthesis of highly stable carboxylated graphene is reported. Here, formate anions act as both intercalation ions and co-reactant acid for the confinement of electro-generated carboxylic radical (●COOH) in the sub-nanometer scaled interlayers, which facilitates the radical addition reaction on graphene sheets. The controllable carboxylation of graphene is realized by tuning the concentration of formate anions in the electrolyte solution. The high crystallinity of the obtained product indicates the occurrence of spatially confined ●COOH addition reaction between the sub-nanometer interlayers of expanded graphite. In addition, the carboxylated graphene have been used for water desalination and hydrogen/oxygen reduction reaction. Therefore, this work provides a new method for the in situ preparation of functionalized graphene through the electrolysis and its applications in water desalination and hydrogen/oxygen reduction reactions.

Massive extrapancreatic solid pseudopapillary neoplasm misdiagnosed as hepatic tumor: a case report and literature review.

Background: Solid pseudopapillary neoplasms (SPNs) of the pancreas are uncommon, low-malignancy neoplasms. Moreover, the occurrence of extrapancreatic SPNs is rarely encountered. Case summary: A 45-year-old female presented with a right upper abdominal mass and abdominal pain for 3 and 1 months as chief complaints, respectively. Initially, the patient was misdiagnosed with hepatocellular carcinoma based on her symptoms and results of physical and imaging examinations. Following multidisciplinary discussion and ruling out surgical contraindications, a decision was taken to proceed with surgical intervention. Interestingly, the tumor was found to originate from the retroperitoneum and had invaded the right half of the liver and the right wall of the inferior vena cava. The operation was uneventful, and the pathological findings confirmed the tumor as an extrapancreatic SPN. The patient remained asymptomatic after 15 months of follow-up. Conclusion: Surgical treatment remains the preferred option for extrapancreatic SPN. The preoperative misdiagnosis also highlights the importance of accurate diagnosis and the development of appropriate treatment strategies for liver masses.

Research Progress of Microbiota-Gut-Brain Axis in Parkinson's Disease.

Parkinson's disease (PD) is a common neurodegenerative disorder characterized by misfolding of α-synuclein. Clinical manifestations include slowly developing resting tremor, muscle rigidity, bradykinesia and abnormal gait. The pathological mechanisms underlying PD are complex and yet to be fully elucidated. Clinical studies suggest that the onset of gastrointestinal symptoms may precede motor symptoms in PD patients. The microbiota-gut-brain axis plays a bidirectional communication role between the enteric nervous system and the central nervous system. This bidirectional communication between the brain and gut is influenced by the neural, immune and endocrine systems related to the gut microbiome. A growing body of evidence indicates a strong link between dysregulation of the gut microbiota and PD. In this review, we present recent progress in understanding the relationship between the microbiota-gut-brain axis and PD. We focus on the role of the gut microbiota, the unique changes observed in the microbiome of PD patients, and the impact of these changes on the progression of PD. Finally, we evaluate the role of current treatment strategies for PD, including probiotics, fecal microbial transplants, dietary modifications, and related drug therapies.

First Description of the Mitogenome Features of Neofoleyellides Genus (Nematoda: Onchocercidae) Isolated from a Wild Bird (Pyrrhocorax pyrrhocorax).

The Onchocercidae family is composed of more than 30 valid nematode species with notable zoonotic potential. Current limitations in molecular characterization methods and species identification are the main obstacles to a better understanding of the biology of Onchocercidae species, particularly in wildlife. This study describes for the first time the complete mitochondrial (mt) genome sequence of Neofoleyellides sp. isolated from a wild bird (Pyrrhocorax pyrrhocorax) and belonging to the Neofoleyellides genus (Nematoda: Onchocercidae). The mt genome of Neofoleyellides sp. (GenBank accession number: ON641583) was a typical circular DNA molecule of 13,628 bp in size with an AT content of 76.69%. The complete mt genome comprised 36 functional subunits, including 12 protein-coding genes (PCGs), 2 ribosomal RNA genes, and 22 transfer RNA genes. The most common start codon was ATT/ATG except for nad2 with TTG, and TAA was the termination codon for all protein-coding genes (PCGs). Phylogenetic analysis of the concatenated and aligned amino acid sequences of the 12 PCGs showed that the trees generated using different methods (Bayesian inference and maximum likelihood) with different partition schemes shared similar topologies. The isolated Neofoleyellides sp. was placed in the Onchocercidae family and formed a sister branch with the genera Onchocerca and Dirofilaria. The entire mt genome of Neofoleyellides sp. presented in this study could provide useful data for studying the population genetics and phylogenetic relationships of Onchocercidae species.

First detection and genomic characterization of a new parvovirus in equines in China.

Equine copivirus (EqCoPV) is a newly discovered parvovirus that infects equines. Currently, it is unclear whether this virus is prevalent in China. In the present study, serum samples were collected from equines in China and were processed for EqCoPV DNA detection by PCR. The results demonstrated that EqCoPV was circulating among the sampled equines, with a low detection rate of 0.94%. The genome sequence of one Chinese EqCoPV strain, UH26, was determined and used for genetic and phylogenetic analysis. The results demonstrated that UH26 has a close genetic relationship to EqCoPV strains from the USA and South Korea. To our knowledge, this is the first report of EqCoPV in China.

Emergence, Evolution, and Pathogenicity of Influenza A(H7N4) Virus in Shorebirds in China.

A 2-year surveillance study of influenza A viruses in migratory birds was conducted to understand the subsequent risk during the migratory seasons in Dandong Yalu River Estuary Coastal Wetland National Nature Reserve, Liaoning Province, China, a major stopover site on the East Asian-Australasian flyway. Overall, we isolated 27 influenza A viruses with multiple subtypes, including H3N8 (n = 2), H4N6 (n = 2), H4N7 (n = 2), H7N4 (n = 9), H7N7 (n = 1), H10N7 (n = 7), and H13N6 (n = 4). Particularly, a novel reassortant influenza A(H7N4) virus was first identified in a woman and her backyard poultry flock in Jiangsu Province, China, posing a serious threat to public health. Here, we describe the genetic characterization and pathogenicity of the nine influenza A(H7N4) isolates. Phylogenetic analysis indicated that complex viral gene flow occurred among Asian countries. We also demonstrated a similar evolutionary trajectory of the surface genes of the A(H7N4) isolates and Jiangsu human-related A(H7N4) viruses. Our A(H7N4) isolates exhibited differing degrees of virulence in mice, suggesting a potential risk to other mammalian species, including humans. We revealed multiple mutations that might affect viral virulence in mice. Our report highlights the importance and need for the long-term surveillance of avian influenza virus in migratory birds combined with domestic poultry surveillance along migratory routes and flyways and, thereby, the development of measures to manage potential health threats. IMPORTANCE The H7 subtype avian influenza viruses, such as H7N2, H7N3, H7N4, H7N7, and H7N9, were documented as being capable of infecting humans, and the H7 subtype low pathogenicity avian influenza viruses are capable of mutating into highly pathogenic avian influenza; therefore, they pose a serious threat to public health. Here, we investigated the evolutionary history, molecular characteristics, and pathogenicity of shorebird-origin influenza A(H7N4) viruses, showing a similar evolutionary trajectory with Jiangsu human A(H7N4) viruses in HA and NA genes. Moreover, our isolates exhibited variable virulence (including moderate virulence) in mice, suggesting a potential risk to other mammalian species, including humans.

Emergence, prevalence, and evolution of H5N8 avian influenza viruses in central China, 2020.

Highly pathogenic influenza A(H5N8) viruses have caused several worldwide outbreaks in birds and are able cross the species barrier to infect humans, posing a substantial threat to public health. After the first detection of H5N8 viruses in deceased swans in Inner Mongolia, we performed early warning and active monitoring along swan migration routes in central China. We isolated and sequenced 42 avian influenza viruses, including 40 H5N8 viruses, 1 H5N2 virus, and 1 H9N2 virus, in central China. Our H5N8 viruses isolated in swan stopover sites and wintering grounds showed high nucleotide homologies in the whole genome, revealing a common evolutionary source. Phylogenetic analysis revealed that the H5 viruses of clade 2.3.4.4b prevalent in 2020 have further diverged into two sub-clades: b1 and b2. The phylogeographic analysis also showed that the viruses of sub-clade b2 most likely originated from poultry in Russia. Notably, whooper swans were found to be responsible for the introduction of sub-clade b2 viruses in central China; whooper and tundra swans play a role in viral spread in the Yellow River Basin and the Yangtze River Basin, respectively. Our findings highlight swans as an indicator species for transborder spreading and monitoring of the H5N8 virus.

Pan-Genome Analysis of Vibrio cholerae and Vibrio metschnikovii Strains Isolated From Migratory Birds at Dali Nouer Lake in Chifeng, China.

Migratory birds are recently recognized as Vibrio disease vectors, but may be widespread transporters of Vibrio strains. We isolated Vibrio cholerae (V. cholerae) and Vibrio metschnikovii (V. metschnikovii) strains from migratory bird epidemic samples from 2017 to 2018 and isolated V. metschnikovii from migratory bird feces in 2019 from bird samples taken from the Inner Mongolia autonomous region of China. To investigate the evolution of these two Vibrio species, we sequenced the genomes of 40 V. cholerae strains and 34 V. metschnikovii strains isolated from the bird samples and compared these genomes with reference strain genomes. The pan-genome of all V. cholerae and V. metschnikovii genomes was large, with strains exhibiting considerable individual differences. A total of 2,130 and 1,352 core genes were identified in the V. cholerae and V. metschnikovii genomes, respectively, while dispensable genes accounted for 16,180 and 9,178 of all genes for the two strains, respectively. All V. cholerae strains isolated from the migratory birds that encoded T6SS and hlyA were non-O1/O139 serotypes without the ability to produce CTX. These strains also lacked the ability to produce the TCP fimbriae nor the extracellular matrix protein RbmA and could not metabolize trimetlylamine oxide (TMAO). Thus, these characteristics render them unlikely to be pandemic-inducing strains. However, a V. metschnikovii isolate encoding the complete T6SS system was isolated for the first time. These data provide new molecular insights into the diversity of V. cholerae and V. metschnikovii isolates recovered from migratory birds.

Prevalence and Risk Factors of Toxoplasma gondii Infection Among Five Wild Rodent Species from Five Provinces of China.

Toxoplasma gondii, an intracellular zoonotic parasite, can infect humans and various animals worldwide. Wild rodents plan an important role as intermediate hosts of T. gondii. Some studies on T. gondii from wild rodents have been published, but the investigation data of T. gondii in wild rodents in China are limited. Therefore, brain tissue samples from 382 wild rodents in four provinces and one autonomous region of China were screened by PCR amplification of T. gondii B1 gene. Furthermore, the wild rodents were identified as five species based on their morphological characteristics, including Citellus dauricus (n = 35 from Heilongjiang), Lasiopodomys brandti (n = 81 from Inner Mongolia), Apodemus agrarius (n = 12 from Heilongjiang), Rattus norvegicus (n = 2 from Heilongjiang; n = 99 from Zhejiang; n = 54 from Shanxi), and Mus musculus (n = 99 from Guangxi). The overall prevalence of T. gondii in these wild rodents was 5.24% (20/382) in this study. At different regions, the highest prevalence of T. gondii was in Guangxi (12.12%) compared with other regions (0% in Heilongjiang; 2.47% in Inner Mongolia; 2.02% in Zhejiang; 7.41% in Shanxi). At different climates, the higher prevalence was found in temperate/mesothermal climates (7.07%) compared with continental/microthermal climates (3.26%). Also, the results showed that M. musculus had the highest prevalence of T. gondii infection (12.12%) among the rodent species sampled. Moreover, sampling year was significantly related to the prevalence of T. gondii in investigated wild rodents (p = 0.0117). This is the first report of T. gondii in wild rodents from Zhejiang, Guangxi, Shanxi, Heilongjiang provinces and Inner Mongolia autonomous region in China, providing the fundamental information for further prevention and control of toxoplasmosis in China.

Predicting cloud condensation nuclei number concentration based on conventional measurements of aerosol properties in the North China Plain.

Cloud condensation nuclei (CCN) play an important role in the formation and evolution of cloud droplets. However, the dataset of global CCN number concentration (NCCN) is still scarce due to the lack of direct CCN measurements, hindering an accurate evaluation of its climate effects. Alternative approaches to determine NCCN have thus been proposed to calculate NCCN based on measurements of other aerosol properties, such as particle number size distribution, bulk aerosol chemical composition and aerosol optical properties. To better understand the interaction between haze pollution and climate, we performed direct CCN measurements in the winter of 2018 at the Gucheng site, a typical polluted suburban site in North China Plain (NCP). The results show that the average CCN concentrations were 3.81 × 103 cm-3, 5.35 × 103 cm-3, 9.74 × 103 cm-3, 1.27 × 104 cm-3, 1.44 × 104 cm-3 at measured supersaturation levels of 0.114%, 0.148%, 0.273%, 0.492% and 0.864%, respectively. Based on these observational data, we have further investigated two methods of calculating NCCN from: (1) bulk aerosol chemical composition and particle number size distribution; (2) bulk aerosol chemical composition and aerosol optical properties. Our results showed that both methods could well reproduce the observed concentration (R2 > 0.88) and variability of NCCN with a 9% to 23% difference in the mean value. Further error analysis shows that the estimated NCCN tends to be underestimated by about 20% during the daytime while overestimated by <10% at night compared with the measured NCCN. These results provide quantitative instructions for the NCCN prediction based on conventional aerosol measurements in the NCP.

Prevalence and Genotyping of Toxoplasma gondii Infection in Raccoon Dogs (Nyctereutes procyonoides) in Northern China.

Toxoplasma gondii is one of protozoan parasites resulting in zoonosis, which can infect nearly all of warm-blooded hosts, including humans and raccoon dogs (Nyctereutes procyonoides). However, related reports on prevalence and genetic characterization of T. gondii strains in raccoon dogs were few in China. The aim of this study was to survey the prevalence and genetic characterization of T. gondii strains in domestic raccoon dogs from Jilin, Liaoning, and Hebei provinces, northern China. During April 2016 to November 2017, a total of 337 tissue samples collected from domestic raccoon dogs were detected with B1 gene using a nested PCR. And the positive samples were genotyped at 11 genetic markers (SAG1, 5'-and 3'-SAG2, alternative SAG2, SAG3, BTUB, GRA6, L358, PK1, c22-8, c29-2, and Apico) using multilocus PCR-restriction fragment length polymorphism technology. Sixteen out of 337 sika deer (4.75%) were positive with B1 gene by nest PCR. Furthermore, four positive DNA samples were completely typed through further being genotyped, in which three samples were identified as ToxoDB Genotype #9, and one sample was confirmed as ToxoDB Genotype #10. The results of molecular detection not only revealed the existence of T. gondii in domestic raccoon dogs in Jilin, Liaoning, and Hebei for the first time, but also provided the information of genetic diversity. This study also indicated that ToxoDB Genotype #9 as a kind of potential reservoir for T. gondii transmission, may be main genotype in domestic raccoon dogs in China, posing a risk of infection in human health.

Seroprevalence and risk factors of hepatitis E virus infection among the Korean, Manchu, Mongol, and Han ethnic groups in Eastern and Northeastern China.

Hepatitis E virus (HEV) infection is a serious public health concern in developing countries. China is regarded as an HEV-endemic area, but epidemiological data for HEV among different nationalities is limited. This study was conducted to estimate the seroprevalence and risk factors of HEV infection in Koreans (n = 520), Manchus (n = 303), Mongols (n = 217), and Hans (n = 802) in Eastern and Northeastern China between 2013 and 2015. A total of 366 (19.87%) out of 1842 samples were seropositive for IgG or IgM HEV-antibodies detected by enzyme-linked immunoassays. Among these groups, the Mongols had the highest seroprevalence of HEV infection (25.35%, 55/217), followed by the Koreans (23.65%, 123/520), the Manchus (19.80%, 60/303), and the Hans (15.96%, 128/802). Multiple analysis showed that the gender, consumption of raw/undercooked meat, source of drinking water, residence area, and age were significantly associated with HEV infection in four ethnic groups. The present results indicated that HEV infection was prevalent in Mongols, Koreans, Manchus, and Hans in the surveyed regions, which demonstrated the higher risk of transmitting HEV in multiple nationalities in Eastern and Northeastern China.

The involvement of AMPA-ERK1/2-BDNF pathway in the mechanism of new antidepressant action of prokinetic meranzin hydrate.

It was recently discovered that ketamine can relieve depression in a matter of hours through an action on α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors. This is much more rapid than the several weeks required for the available antidepressants to show therapeutic efficacy. However, ketamine has negative side effects. The aim of this study was to determine whether the natural prokinetic drug meranzin hydrate (MH) has a fast-acting antidepressant effect mediated by AMPA receptors. By means of in vivo and in vitro experiments, we found that (1) treatment of rats with MH at 9 mg/kg decreased immobility time in a forced swimming test (FST), as did the popular antidepressant fluoxetine and the AMPA receptor positive modulator aniracetam. Pretreatment of rats with NBQX (10 mg/kg), an antagonist of AMPA receptors, blocked this effect of MH. (2) MH increased number of crossings of forced swimming rats in the open field test. (3) FST enhanced hippocampal ERK1/2, p-ERK1/2 and BDNF expression levels. MH (9 mg/kg) treatment further up-regulated hippocampal p-ERK1/2 and BDNF expression levels, and this effect was prevented by NBQX. (4) MH-increased BDNF expression corresponded with MH-decreased immobility time in the FST. (5) In vitro experiments, we found that incubation of rats hippocampus slices with MH (10, 20 µM respectively) increased concentrations of BDNF and p-ERK1/2. This effect of MH (20 µM) were prevented by NBQX. In conclusion, in animals subjected to acute stress, the natural prokinetic drug MH produced a rapid effect mediated by AMPA receptors and involving BDNF modulation through the ERK1/2 pathway.