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1.
Se Pu ; 41(10): 835-842, 2023 Oct.
Article in Chinese | MEDLINE | ID: mdl-37875406

ABSTRACT

Capillary electrochromatography (CEC) has received increased attention from the academic community because it combines the excellent selectivity of high performance liquid chromatography (HPLC) and the high efficiency of capillary electrophoresis (CE). Selecting the most appropriate stationary phase material is crucial to achieve better separation effects in CEC. In recent years, a considerable number of materials, such as graphene oxide, proteins, metal organic frameworks, and covalent organic frameworks (COFs), have been widely used as stationary phases in CEC to further improve its separation performance and extend its scope of potential applications. Among these materials, COFs have shown great application prospects in CEC owing to their unique properties, which include high porosity, large surface area, excellent stability, tunable pore size, and high designability of the framework structure. This review systematically summarizes published papers on the development and application of COFs in CEC from 2016 to 2023. First, two COF-based capillary columns (i. e., open-tube CEC columns and monolithic CEC columns) and their preparation methods are introduced. Second, the applications of CEC based on COF stationary phases in the separation of environmental endocrine disruptors, pesticides, aromatic compounds, amino acids, and drugs, particularly chiral drugs, are systematically summarized. The separation mechanism of CEC based on COF stationary phases is also introduced. At present, the good separation ability of COF-based CEC is mainly attributed to two factors: 1) The size exclusion effect of the pores of the COF stationary phase. Because of differences in the sizes of their organic molecular building units and side chains, COFs have varying pore sizes and topological structures. Thus, target analytes smaller than the pores of the COFs can enter the frameworks and interact with them during separation. On the other hand, target analytes larger than the pores of the COFs cannot enter the frameworks and interact with them during separation; thus, they can be separated. 2) The interactions between the target analytes and side chains (e. g., hydrophobic interactions, hydrogen bonding, π-π interactions, etc.) of the COFs. Since COFs usually contain alkyl side chains, aromatic structures, and oxygen and/or nitrogen atoms with high electronegativity, various interactions could occur between the COFs and target analytes. Finally, directions for the future development and strategic application of CEC based on COF stationary phases are proposed. We believe that future research in CEC based on COF stationary phases should focus on the following aspects: 1) The use of cheminformatics to design and construct COFs to improve the efficiency of COF capillary column preparation; 2) the development of milder methods to synthesize COFs that can meet the requirements of high performance COF capillary columns; and 3) in-depth research to explore the separation mechanism of CEC based on COF stationary phases to provide theoretical guidance for developing CEC methods suitable for the separation and analysis of complex samples.

2.
Insect Sci ; 28(5): 1399-1413, 2021 Oct.
Article in English | MEDLINE | ID: mdl-32677271

ABSTRACT

Mermithid nematodes, such as Ovomermis sinensis, are used as biological control agents against many insect pests, including cotton bollworm (Helicoverpa armigera). However, given the host's robust immune system, the infection rate of O. sinensis is low, thus restricting its widespread use. To understand the host defense mechanisms against mermithid nematodes, we identified and characterized a protein involved in the recognition of O. sinensis, the potential O. sinensis-binding protein C-type lectin 1 (HaCTL1a and/or HaCTL1b), which was eluted from the surface of O. sinensis after incubation with H. armigera plasma. HaCTL1b is homologous to the previously reported HaCTL1a protein. HaCTL1 was predominantly expressed in hemocytes and was induced by the steroid hormone 20-hydroxyecdysone through ecdysone receptor (HaEcR) or ultraspiracle (HaUSP), or both. Binding assays confirmed the interactions of the HaCTL1 proteins with O. sinensis but not with Romanomermis wuchangensis, a parasitic nematode of mosquito. Moreover, the HaCTL1 proteins were secreted into the hemocoel and promoted hemocyte-mediated encapsulation and phagocytosis. A knockdown of HaEcR and/or HaUSP resulted in compromised encapsulation and phagocytosis. Thus, HaCTL1 appears to modulate cellular immunity in the defense against parasitic nematodes, and the 20-hydroxyecdysone-HaEcR-HaUSP complex is involved in regulating the process.


Subject(s)
Ecdysterone/immunology , Immunity, Cellular , Lectins, C-Type/immunology , Moths , Animals , Hemocytes , Insect Proteins/immunology , Larva , Moths/immunology , Moths/parasitology , Nematoda , Phagocytosis
3.
Oxid Med Cell Longev ; 2020: 5715893, 2020.
Article in English | MEDLINE | ID: mdl-32184917

ABSTRACT

Vitamin D deficiency has been reported in alcoholics. This study is aimed at evaluating the effects of vitamin D deficiency on chronic alcohol-induced liver injury in mice. Mice were fed with modified Lieber-DeCarli liquid diets for 6 weeks to establish an animal model of chronic alcohol-induced liver injury. In the VDD+EtOH group, mice were fed with modified diets, in which vitamin D was depleted. Vitamin D deficiency aggravated alcohol-induced liver injury. Furthermore, vitamin D deficiency aggravated hepatocyte apoptosis during alcohol-induced liver injury. Although it has a little effect on hepatic TG content, vitamin D deficiency promoted alcohol-induced hepatic GSH depletion and lipid peroxidation. Further analysis showed that vitamin D deficiency further increased alcohol-induced upregulation of hepatic inducible nitric oxide synthase (inos), two NADPH oxidase subunits p47phox and gp91phox, and heme oxygenase- (HO-) 1. By contrast, vitamin D deficiency attenuated alcohol-induced upregulation of hepatic antioxidant enzyme genes, such as superoxide dismutase (sod) 1 and gshpx. In addition, vitamin D deficiency significantly elevated alcohol-induced upregulation of hepatic proinflammatory cytokines and chemokines. Taken together, these results suggest that vitamin D deficiency aggravates hepatic oxidative stress and inflammation during chronic alcohol-induced liver injury.


Subject(s)
Chemical and Drug Induced Liver Injury, Chronic/etiology , Inflammation/etiology , Liver/pathology , Oxidative Stress , Vitamin D Deficiency/complications , Alcohol Dehydrogenase/metabolism , Aldehyde Dehydrogenase/metabolism , Animals , Body Weight , Chemical and Drug Induced Liver Injury, Chronic/blood , Chemokines/metabolism , Energy Intake , Inflammation/blood , Liver/enzymology , Mice, Inbred C57BL , Triglycerides/blood , Up-Regulation , Vitamin D/analogs & derivatives , Vitamin D/blood , Vitamin D Deficiency/blood
4.
BMC Genomics ; 20(1): 161, 2019 Feb 27.
Article in English | MEDLINE | ID: mdl-30813894

ABSTRACT

BACKGROUND: Mermithid nematodes, such as Ovomermis sinensis, display a broad host range including some lepidopteran pests. Infective juveniles penetrate their host through the cuticle, complete their growth within the hemocoel and eventually kill the host upon their emergence. Hence, mermithid nematodes are considered potential biological control agents of insect pests. Our previous data indicate that the infection rate of O. sinensis on cotton bollworm (Helicoverpa armigera) is low, which may be largely due to the strong immune system of the host. However, current knowledge on the interactions of mermithid nematodes with their hosts and the mechanisms employed by hosts to defend themselves against mermithid nematodes is limited. RESULTS: Here, we investigated the response of H. armigera to O. sinensis infection. Parasitism by O. sinensis caused a sharp decline in the survival rate of H. armigera. The hemocytic phagocytosis ability, antibacterial activity, and phenoloxidase (PO) activity in plasma of H. armigera increased at 1 d post parasitism (dpp) but decreased at 3 dpp. Further, we investigated gene expression in the fat body of parasitized and non-parasitized H. armigera larvae at 1, 3, and 5 dpp using a digital gene expression system. In total, 41, 60 and 68 immune-related differentially expressed genes were identified at 1, 3, and 5 dpp, respectively. These genes encoded pattern recognition receptors (PRRs), antimicrobial peptides (AMPs), serine proteases (SPs), SP inhibitors, mucins and other immune-related proteins. The expression of most PRRs, AMPs, SPs, and mucins was upregulated in the fat body of larvae at 1 dpp, downregulated at 3 dpp, and then again upregulated at 5 dpp by O. sinensis. The increased expression of SP inhibitors may contribute to the inhibited PO activity at 5 dpp. CONCLUSIONS: This study demonstrates that parasitism by O. sinensis modulates the immune reaction of the host H. armigera by altering the expression of immune-related genes. Our data provide a basis for future investigation of the molecular mechanisms employed by the mermithid nematode O. sinensis to modulate the immunity of the host H. armigera. These data will also likely facilitate the improvement of success in parasitism of H. armigera by O. sinensis.


Subject(s)
Mermithoidea/physiology , Moths/immunology , Moths/parasitology , Animals , Gene Expression Profiling , Larva/immunology , Larva/parasitology , Moths/genetics , Moths/metabolism , Receptors, Pattern Recognition/genetics , Receptors, Pattern Recognition/metabolism , Sequence Analysis, RNA , Serine Proteases/genetics , Serine Proteases/metabolism , Survival Analysis
5.
Insect Biochem Mol Biol ; 86: 29-40, 2017 07.
Article in English | MEDLINE | ID: mdl-28572000

ABSTRACT

The encapsulation reaction in invertebrates is analogous to granuloma formation in vertebrates, and this reaction is severely compromised when ecdysone signaling is blocked. However, the molecular mechanism underlying the encapsulation reaction and its regulation by ecdysone remains obscure. In our previous study, we found that the C-type lectin HaCTL3, from the cotton bollworm Helicoverpa armigera, is involved in anti-bacterial immune response, acting as a pattern recognition receptor (PRR). In the current study, we demonstrate that HaCTL3 is involved in defense against parasites and directly binds to the surface of nematodes. Our in vitro and in vivo studies indicate that HaCTL3 enhances hemocytic encapsulation and melanization, whereas H. armigera ß-integrin (Haß-integrin), located on the surface of hemocytes, participates in encapsulation. Additionally, co-immunoprecipitation experiments reveal HaCTL3 interacts with Haß-integrin, and knockdown of Haß-integrin leads to reduced encapsulation of HaCTL3-coated beads. These results indicate that Haß-integrin serves as a hemocytic receptor of HaCTL3 during the encapsulation reaction. Furthermore, we demonstrate that 20-hydroxyecdysone (20E) treatment dramatically induces the expression of HaCTL3, and knockdown of the 20E receptor (EcR)/ultraspiracle (USP), abrogates this response. Overall, this study provides the first evidence of the presence of a hemocytic receptor (Haß-integrin), that interacts with the PRR HaCTL3 to facilitate encapsulation reaction in insects and demonstrates the regulation of this process by the steroid hormone ecdysone.


Subject(s)
Host-Parasite Interactions/immunology , Integrin beta Chains/metabolism , Lectins, C-Type/metabolism , Moths/immunology , Nematoda/immunology , Animals , Ecdysterone , Hemocytes/metabolism , Melanins/metabolism , Moths/metabolism , Moths/parasitology , Rabbits , Receptors, Steroid/metabolism
6.
Article in English | MEDLINE | ID: mdl-28232041

ABSTRACT

This article has been withdrawn at the request of the editor and publisher. The publisher regrets that an error occurred which led to the premature publication of this paper. This error bears no reflection on the article or its authors. The publisher apologizes to the authors and the readers for this unfortunate error. The article was subsequently accepted and published and can be viewed here: https://doi.org/10.1016/j.ibmb.2017.05.005 The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

7.
Mitochondrial DNA A DNA Mapp Seq Anal ; 27(3): 1763-4, 2016 05.
Article in English | MEDLINE | ID: mdl-25259460

ABSTRACT

In order to further study the characteristic of Caenorhabditis, the complete mitochondrial genome (mitogenome) of a modal nematode species Caenorhabditis tropicalis n. sp. (previous species name: C. sp. 11) was determined. The results showed that the mitogenome was 13,874 bp in length, which contained 12 protein-coding genes (PCGs), 2 ribosomal RNA genes (rRNAs), 22 transfer RNA genes (tRNAs), an AT-rich region and 2 non-coding regions (NCR). The base composition of the heavy strand was 28.12% A, 47.57% T, 15.53% G, and 8.78% C. Furthermore, it is more significant that this mitogenome has two unique features: One is the AT-rich region which had 4 runs of 12 AT dinucleotides and 4 copies of directly repeated sequence (47 bp) within a pair of inverted repeat sequence (13 bp), and the other is that the NCR (130 bp) between tRNA(Arg) and tRNA(Gln) of 4 small stem-loop which was described at the first time. This paper firstly expounded the the complete mitogenome of C. tropicalis n. sp. So it can enrich the molecular resource and facilitate the further research of the population genetics and systematics for Caenorhabditis.


Subject(s)
Genome, Mitochondrial/genetics , Rhabditida/genetics , Animals , Base Composition/genetics , Gene Order/genetics , Phylogeny , RNA, Ribosomal/genetics , RNA, Transfer/genetics , Rhabditida/classification , Sequence Analysis, DNA
8.
J Am Coll Nutr ; 33(2): 120-8, 2014.
Article in English | MEDLINE | ID: mdl-24724769

ABSTRACT

OBJECTIVE: Our objective was to examine associations between dietary patterns and body mass index (BMI) and bone mineral density (BMD) in Chinese freshmen. METHODS: A cross-sectional study was done in 1319 college freshmen (aged 18.1 ± 1.2 years old). Diet was assessed by using a validated self-administrated food-frequency questionnaire. Blood pressure, weight, height, waist circumference, and hip circumference were measured and bone measurements were done using Quantitative Ultrasound System. RESULTS: Four dietary patterns were identified by factor analysis: Western food, animal protein, calcium food, and Chinese traditional patterns. The prevalence of overweight/obesity and osteopenia/osteoporosis were 8.2% (108/1319) and 28.1% (371/1319). The highest tertile of Western food pattern scores had greater odds of overweight/obesity (highest vs. lowest tertile, odds ratio [OR] = 2.00, 95% confidence interval [CI], 1.24-3.22), and the highest tertile of Chinese traditional pattern scores had lower risk of overweight/obesity (highest vs. lowest tertile, OR = 0.65, 95% CI, 0.53-0.80) in an adjusted model. The calcium food pattern and Chinese traditional pattern were negatively associated with the risk of osteopenia/osteoporosis (highest vs. lowest tertile, OR = 0.59, 95% CI, 0.41-0.87; OR = 0.78, 95% CI, 0.55-0.89) after adjusting for confounders. CONCLUSION: These findings suggested that there was a positive correlation between Chinese traditional dietary pattern and healthy BMI and BMD and that this same association existed between calcium food pattern and BMD in Chinese freshmen. In contrast, the Western-style diet was negatively correlated with healthy BMI in Chinese freshmen.


Subject(s)
Body Mass Index , Body Weight/physiology , Bone Density/physiology , Diet , Adolescent , Asian People , Blood Pressure/physiology , Body Composition , China , Cross-Sectional Studies , Feeding Behavior , Female , Humans , Male , Nutrition Surveys , Surveys and Questionnaires , Waist Circumference/physiology , Young Adult
9.
Dongwuxue Yanjiu ; 33(5): 487-92, 2012 Oct.
Article in Chinese | MEDLINE | ID: mdl-23019030

ABSTRACT

Mermithidae, as an important natural predator of pests such as Bollworm, has great potential for natural biological control of invasive pests. Unfortunately, the in vitro culture of the nematode has not yet been successful, delaying the commercial application of this pest control method. The key reason for this failure is the inability of the worms to accomplish sex differentiation, sparking a strong interest in this process. Here, we analyzed the differences in gene expression of female and male postparasitic Ovomermis sinensis juveniles by mRNA differential display. In total, 20 gene fragments that had differential expression in male and female worms were isolated, including 8 male- and 12 female-specific ones. Bioinformatics methods were employed to analyze sequences of these fragments, in which ensembl analysis shows 4 fragments have comparable parts with C. elegence's X chromosome, we speculate those fragments are important genes which influence sex differentiation of Ovomermis sinensis, This data provides an idea for further study of the molecular mechanism of sex differentiation in mermithids.


Subject(s)
Helminth Proteins/genetics , Mermithoidea/genetics , Moths/parasitology , Animals , Female , Helminth Proteins/chemistry , Helminth Proteins/metabolism , Male , Mermithoidea/chemistry , Mermithoidea/metabolism , Molecular Sequence Data , Sequence Homology, Nucleic Acid , Sex Differentiation
10.
Genetics ; 191(4): 1257-69, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22649079

ABSTRACT

Mating system transitions dramatically alter the evolutionary trajectories of genomes that can be revealed by contrasts of species with disparate modes of reproduction. For such transitions in Caenorhabditis nematodes, some major causes of genome variation in selfing species have been discerned. And yet, we have only limited understanding of species-wide population genetic processes for their outcrossing relatives, which represent the reproductive state of the progenitors of selfing species. Multilocus-multipopulation sequence polymorphism data provide a powerful means to uncover the historical demography and evolutionary processes that shape genomes. Here we survey nucleotide polymorphism across the X chromosome for three populations of the outcrossing nematode Caenorhabditis remanei and demonstrate its divergence from a fourth population describing a closely related new species from China, C. sp. 23. We find high genetic variation globally and within each local population sample. Despite geographic barriers and moderate genetic differentiation between Europe and North America, considerable gene flow connects C. remanei populations. We discovered C. sp. 23 while investigating C. remanei, observing strong genetic differentiation characteristic of reproductive isolation that was confirmed by substantial F2 hybrid breakdown in interspecific crosses. That C. sp. 23 represents a distinct biological species provides a cautionary example of how standard practice can fail for mating tests of species identity in this group. This species pair permits full application of divergence population genetic methods to obligately outcrossing species of Caenorhabditis and also presents a new focus for interrogation of the genetics and evolution of speciation with the Caenorhabditis model system.


Subject(s)
Caenorhabditis/genetics , Genetics, Population , Animals , Biological Evolution , Caenorhabditis/classification , China , Crosses, Genetic , Europe , Genetic Loci , Genome, Helminth , Molecular Sequence Data , North America , Phylogeny , Polymorphism, Genetic , Population Dynamics , Reproduction/genetics , Reproductive Isolation , X Chromosome
11.
Mol Ecol ; 21(6): 1345-59, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22320847

ABSTRACT

Molecular hyperdiversity has been documented in viruses, prokaryotes and eukaryotes. Such organisms undermine the assumptions of the infinite-sites mutational model, because multiple mutational events at a site comprise a non-negligible portion of polymorphisms. Moreover, different sampling schemes of individuals from species with subdivided populations can profoundly influence resulting patterns and interpretations of molecular variation. Inspired by molecular hyperdiversity in the nematode Caenorhabditis sp. 5, which exhibits average pairwise differences among synonymous sites of >5% as well as modest population structure, we investigated via coalescent simulation the joint effects of a finite-sites mutation (FSM) process and population subdivision on the variant frequency spectrum. From many demes interconnected through a stepping-stone migration model, we constructed local samples from a single deme, pooled samples from several demes and scattered samples of a single individual from numerous demes. Compared with a single panmictic population at equilibrium, we find that high population mutation rates induce a deficit of rare variants (positive Tajima's D) under a FSM model. Population structure also induces such a skew for local samples when migration is high and for pooled samples when migration is low. Contrasts of sampling schemes for C. sp. 5 imply high mutational input coupled with high migration. We propose that joint analysis of local, pooled and scattered samples for species with subdivided populations provides a means of improving inference of demographic history, by virtue of the partially distinct patterns of polymorphism that manifest when sequences are analyzed according to differing sampling schemes.


Subject(s)
Caenorhabditis/genetics , Genetic Variation , Genetics, Population , Mutation Rate , Polymorphism, Genetic , Animals , Base Sequence , Caenorhabditis/classification , Female , Male , Molecular Sequence Data , Mutation , Sequence Analysis, DNA
12.
Mol Ecol ; 19(22): 5022-9, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20958820

ABSTRACT

Most relatives of the self-fertilizing hermaphroditic nematode model organism Caenorhabditis elegans reproduce via obligate outbreeding between males and females, which also represents the ancestral mode of reproduction within the genus. However, little is known about the scope of genetic diversity and differentiation within such gonochoristic species, especially those found outside of temperate Europe and North America. It is critical to understand the evolutionary processes operating in these species to provide a framework for deciphering the evolution of hermaphroditism and a baseline for the application of outcrossing Caenorhabditis to problems in evolutionary genetics. Here, we investigate for the first time molecular sequence variation for Caenorhabditis sp. 5, a species found commonly in eastern Asia. We identify enormous levels of standing genetic variation that approach the levels observed in the marine broadcast-spawning sea squirt, Ciona savignyi. Although we document significant isolation by distance, we demonstrate that the high polymorphism within C. sp. 5 is not because of strong differentiation among populations or to the presence of cryptic species. These findings illustrate that molecular population genetic approaches to studying obligately outbreeding species of Caenorhabditis will prove powerful in identifying and characterizing functionally and evolutionarily important features of the genome.


Subject(s)
Caenorhabditis/genetics , Genetic Variation , Animals , Evolution, Molecular , Asia, Eastern , Female , Inbreeding , Linkage Disequilibrium , Male , Molecular Sequence Data , Polymorphism, Genetic , Sequence Analysis, DNA
14.
J Nanosci Nanotechnol ; 6(1): 1-15, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16573064

ABSTRACT

In lithium-ion batteries, nanocrystalline intermetallic alloys, nanosized composite materials, carbon nanotubes, and nanosized transition-metal oxides are all promising new anode materials, while nanosized LiCoO2, LiFePO4, LiMn2O4, and LiMn2O4 show higher capacity and better cycle life as cathode materials than their usual larger-particle equivalents. The addition of nanosized metal-oxide powders to polymer electrolyte improves the performance of the polymer electrolyte for all solid-state lithium rechargeable batteries. To meet the challenge of global warming, a new generation of lithium rechargeable batteries with excellent safety, reliability, and cycling life is needed, i.e., not only for applications in consumer electronics, but especially for clean energy storage and for use in hybrid electric vehicles and aerospace. Nanomaterials and nanotechnologies can lead to a new generation of lithium secondary batteries. The aim of this paper is to review the recent developments on nanomaterials and nanotechniques used for anode, cathode, and electrolyte materials, the impact of nanomaterials on the performance of lithium batteries, and the modes of action of the nanomaterials in lithium rechargeable batteries.


Subject(s)
Electric Power Supplies , Electrodes , Lithium Compounds , Nanotechnology/instrumentation , Nanotechnology/methods , Electronics , Ions
15.
Yi Chuan ; 27(1): 150-4, 2005 Jan.
Article in Chinese | MEDLINE | ID: mdl-15730975

ABSTRACT

Sex determination of Drosophila melanogaster and Caeborhabditis elegans has been known in detail. Great progress, is achieved in recent years, is the research of transformer genes, which are those of most important genes in sex determination in both species. In this paper, molecular character, genetic function and the relative genes of transformer genes are particularly described. On the basis,a primary comparison and analysis between the molecular mechanism of sex determination in C.elegans and D. melanogaster are presented.


Subject(s)
Caenorhabditis elegans Proteins/genetics , Caenorhabditis elegans/genetics , Cell Cycle Proteins/genetics , Drosophila Proteins/genetics , Drosophila/genetics , Ribonucleoproteins/genetics , Sex Determination Processes , Animals , DNA-Binding Proteins/genetics , Female , Introns , Male , Nerve Tissue Proteins/genetics , Nuclear Proteins/genetics , RNA, Messenger/genetics , Transcription Factors/genetics
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