Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 67
Filter
1.
J Vis Exp ; (204)2024 Feb 02.
Article in English | MEDLINE | ID: mdl-38372363

ABSTRACT

DNA double-strand breaks (DSBs) represent the most perilous DNA lesions, capable of inducing substantial genetic information loss and cellular demise. In response, cells employ two primary mechanisms for DSB repair: nonhomologous end joining (NHEJ) and homologous recombination (HR). Quantifying the efficiency of NHEJ and HR separately is crucial for exploring the relevant mechanisms and factors associated with each. The NHEJ assay and HR assay are established methods used to measure the efficiency of their respective repair pathways. These methods rely on meticulously designed plasmids containing a disrupted green fluorescent protein (GFP) gene with recognition sites for endonuclease I-SceI, which induces DSBs. Here, we describe the extrachromosomal NHEJ assay and HR assay, which involve co-transfecting HEK-293T cells with EJ5-GFP/DR-GFP plasmids, an I-SceI expressing plasmid, and an mCherry expressing plasmid. Quantitative results of NHEJ and HR efficiency are obtained by calculating the ratio of GFP-positive cells to mCherry-positive cells, as counted by flow cytometry. In contrast to chromosomally integrated assays, these extrachromosomal assays are more suitable for conducting comparative investigations involving multiple established stable cell lines.


Subject(s)
DNA Breaks, Double-Stranded , DNA Repair , Humans , Green Fluorescent Proteins/genetics , HEK293 Cells , Homologous Recombination , DNA End-Joining Repair
2.
DNA Repair (Amst) ; 133: 103603, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38029687

ABSTRACT

Cytoplasmic FAM21 works as a guiding protein in Wiskott-Aldrich Syndrome Protein and SCAR Homolog (WASH) complex by linking WASH complex to endosomes through its interaction with retromer. Recently, we have reported that nuclear WASH localizes to DNA double strand break (DSB) sites to promote DNA repair through non-homologous end-joining (NHEJ). However, whether FAM21, the close partner of WASH, is involved in the nuclear WASH localization and DNA repair remains to be clarified. Here, we show that FAM21 interacts with Ku and the interaction between C-terminal FAM21 and Ku is essential for its recruitment to DSB sites. Moreover, FAM21 depletion led to decreases in WASH recruitment to damaged DNA and repair capacity upon DNA damage. Taken together, these results reveal that FAM21 promotes DNA repair by orchestrating the recruitment of WASH to DSB sites, providing a mechanistic insight into WASH-dependent DNA DSB repair.


Subject(s)
DNA Repair , Proteins , DNA End-Joining Repair , DNA Damage , DNA , Ku Autoantigen
3.
Vaccine ; 41(40): 5825-5833, 2023 09 15.
Article in English | MEDLINE | ID: mdl-37580210

ABSTRACT

BACKGROUND: The global burden of disease caused by congenital cytomegalovirus (CMV) infection is high. Previous modeling studies have suggested that CMV vaccination may be cost-effective in developed countries. Congenital CMV infection is more likely driven by maternal non-primary infection in China. We aimed to measure the effectiveness and cost-effectiveness of population-level CMV vaccination in Chinese females. METHODS: A decision tree Markov model was developed to simulate potential CMV vaccination strategies in a multi-cohort setting, with a population size of 1,000,000 each for the infant, adolescent (10-year-old) and young adult (20-year-old) cohorts. The hypothetical vaccines were assumed to have 50% efficacy, 20 years of protection, 70% coverage, at a price of US$120/dose for base-case analysis. Costs and disability-adjusted life years (DALYs) were discounted by 3% per year and the vaccination would be considered cost-effective if an incremental cost-effectiveness ratio (ICER) was lower than 2021 Chinese per capita GDP (US$12,500). FINDINGS: For the pre-infection (PRI) vaccine efficacy type, the adolescent strategy was the most cost-effective, with an ICER of US$12,213 (12,134 to 12,291) pre DALY averted, compared with the next best strategy (young adult strategy). For pre- and post-infection (P&PI) efficacy type, the young adult strategy was the most cost-effective as it was cost-saving. In one-way analysis varying the PRI vaccine price, the infant strategy, adolescent strategy and the young adult strategy would be a dominant strategy over others if the vaccine cost ≤US$60, US$61-121 and US$122-251 per dose respectively. In contrast, the young adult strategy continued to be the preferred strategy until the P&PI vaccine price exceeded US$226/dose. Our main results were robust under a wide variety of sensitivity analyses and scenario analyses. INTERPRETATION: CMV vaccination for females would be cost-effective and even cost-saving in China. Our findings had public health implications for control of CMV diseases.


Subject(s)
Cytomegalovirus Infections , Cytomegalovirus , Infant , Female , Adolescent , Young Adult , Humans , Child , Adult , Cost-Benefit Analysis , Vaccination/methods , Cytomegalovirus Infections/prevention & control , China
4.
Neural Regen Res ; 18(9): 1956-1960, 2023 Sep.
Article in English | MEDLINE | ID: mdl-36926719

ABSTRACT

Studies have shown that serum response factor is beneficial for axonal regeneration of peripheral nerves. However, its role after central nervous system injury remains unclear. In this study, we established a rat model of T9-T10 spinal cord transection injury. We found that the expression of serum response factor in injured spinal cord gray matter neurons gradually increased with time, reached its peak on the 7th day, and then gradually decreased. To investigate the role of serum response factor, we used lentivirus vectors to overexpress and silence serum response factor in spinal cord tissue. We found that overexpression of serum response factor promoted motor function recovery in rats with spinal cord injury. Qualitative observation of biotinylated dextran amine anterograde tracing showed that overexpression of serum response factor increased nerve fibers in the injured spinal cord. Additionally, transmission electron microscopy showed that axon and myelin sheath morphology was restored. Silencing serum response factor had the opposite effects of overexpression. These findings suggest that serum response factor plays a role in the recovery of motor function after spinal cord injury. The underlying mechanism may be related to the regulation of axonal regeneration.

5.
Zhonghua Nan Ke Xue ; 29(5): 461-466, 2023 May.
Article in Chinese | MEDLINE | ID: mdl-38602766

ABSTRACT

Current diagnostic techniques for male infertility primarily require invasive testing of sperm. Clinically, there is a need for a reliable, non-invasive analysis method that provides precise information about sperm quality without compromising sperm cell integrity. Raman spectroscopy, utilizing the inelastic scattering spectra of light, offers a rapid, simple, repeatable, and non-destructive approach for both qualitative and quantitative analysis, gaining widespread application in medicine. This paper reviews the fundamental characteristics of Raman spectroscopy and its applications in the male reproductive system.


Subject(s)
Infertility, Male , Spectrum Analysis, Raman , Male , Humans , Semen , Spermatozoa , Infertility, Male/diagnosis , Genitalia, Male
6.
Front Oncol ; 11: 697227, 2021.
Article in English | MEDLINE | ID: mdl-34568026

ABSTRACT

The resistance to radiotherapy in lung cancer can be attributed to vasculogenic mimicry (VM) to some extent. Celecoxib (CXB), a selective inhibitor of cyclooxygenase-2 (COX-2), is reported as a radiosensitizer in non-small cell lung cancer (NSCLC). However, whether CXB can regulate VM formation via an off-target effect to radiosensitize NSCLC remains unclear. This study aimed to elucidate the mechanism underlying the radiosensitizing effect of CXB on NSCLC, i.e., whether CXB can inhibit VM formation via binding to newly identified targets other than COX-2. CXB radiosensitivity assay was performed in BALB/c mice bearing H460 xenografts and C57 mice bearing Lewis lung cancer (LLC) xenografts, which were divided into the control, CXB, irradiation (IR) treatment, and IR plus CXB groups. VM formation was observed using 3D Matrigel, periodic acid solution (PAS) staining, and immunofluorescence staining. The potential off-targets of CXB were screened using Protein Data Bank (PDB) database, MGLTools 1.5.6, and AutoDock Vina 1.1.2 and confirmed by Western blotting, enzyme activity assay, and RNA interference in vitro experiments and by immunohistochemistry in vivo experiments. CXB treatment almost eliminated the enhancement of VM formation by IR in vitro and in vivo, partially due to COX-2 inhibition. Four potential off-targets were predicted by molecular docking. Among them, aminopeptidase N (APN) and integrin alpha-V (ITAV) were remarkably inhibited in protein expression and enzyme activity in vitro or in vivo, consistent with the remarkable reduction of VM formation in H460 xenografts in BALB/c mice. In conclusion, CXB dramatically blocked VM through inhibiting newly identified off-targets APN and ITAV, other than COX-2, then radiosensitizing NSCLC.

8.
Neural Regen Res ; 16(11): 2316-2323, 2021 Nov.
Article in English | MEDLINE | ID: mdl-33818518

ABSTRACT

Although the transcriptional alterations inside the facial nucleus after facial nerve injury have been well studied, the gene expression changes in the facial nerve trunk after injury are still unknown. In this study, we established an adult rat model of facial nerve crush injury by compressing the right lateral extracranial nerve trunk. Transcriptome sequencing, differential gene expression analysis, and cluster analysis of the injured facial nerve trunk were performed, and 39 intersecting genes with significant variance in expression were identified. Gene Ontology annotation and Kyoto Encyclopedia of Genes and Genomes pathway analyses of the 39 intersecting genes revealed that these genes are mostly involved in leukocyte cell-cell adhesion and phagocytosis and have essential roles in regulating nerve repair. Quantitative real-time polymerase chain reaction assays were used to validate the expression of pivotal genes. Finally, nine pivotal genes that contribute to facial nerve recovery were identified, including Arhgap30, Akr1b8, C5ar1, Csf2ra, Dock2, Hcls1, Inpp5d, Sla, and Spi1. Primary Schwann cells were isolated from the sciatic nerve of neonatal rats. After knocking down Akr1b8 in Schwann cells with an Akr1b8-specific small interfering RNA plasmid, expression levels of monocyte chemoattractant protein-1 and interleukin-6 were decreased, while cell proliferation and migration were not obviously altered. These findings suggest that Akr1b8 likely regulates the interaction between Schwann cells and macrophages through regulation of cytokine expression to promote facial nerve regeneration. This study is the first to reveal a transcriptome change in the facial nerve trunk after facial nerve injury, thereby revealing the potential mechanism underlying repair of facial nerve injury. This study was approved by the Animal Ethics Committee of Nantong University, China in 2018 (approval No. S20180923-007).

9.
Infect Genet Evol ; 85: 104562, 2020 11.
Article in English | MEDLINE | ID: mdl-32961362

ABSTRACT

The Japanese threadfin bream N. japonicus (Bloch) (Perciformes: Nemipteridae) is an important marine food fish in Asia. However, our present knowledge of the occurrence of its nematode parasites is still limited. In the present study, the species composition and infection rate of ascaridoid nematodes in N. japonicus from the South China Sea, were studied for the first time. Five ascaridoid species, namely Anisakis typica (L3), Hysterothylacium amoyense (L3), Hysterothylacium sp. IV-A (L3), adult of H. thalassini and Raphidascaris lophii (L3), were identified using integrative taxonomy. Hysterothylacium amoyense was the most prevalent species (prevalence 47.2%, mean intensity 14.9 ± 17.1). Hysterothylacium thalassini and R. lophii were reported in the Japanese threadfin bream for the first time. Two different genotypes of A. typica (overall prevalence of 3.4%; mean intensity 1.7 ± 0.9) were found in the South China Sea for the first time. The unique restriction polymorphism patterns of three species of Hysterothylacium are provided for rapid diagnosis. Our present results indicate that RFLP analysis of ITS region, using the restriction enzymes HhaI and RsaI, represents a simple and practical method for large-scale surveys of Hysterothylacium for seafood industry.


Subject(s)
Ascaridida Infections/parasitology , Ascaridoidea/classification , Ascaridoidea/genetics , Fishes/parasitology , Seafood/parasitology , Animals , Ascaridida Infections/diagnosis , Ascaridida Infections/epidemiology , Ascaridida Infections/transmission , China/epidemiology , Food Safety , Molecular Epidemiology , Polymorphism, Single Nucleotide , Zoonoses
10.
Taiwan J Obstet Gynecol ; 59(4): 575-579, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32653132

ABSTRACT

OBJECTIVE: To analyze the correlation between placenta related disease of pregnant women with antecedent hysteroscopic adhesiolysis due to intrauterine adhesions (IUA). MATERIALS AND METHODS: This is a single center, non-randomized, open-label, retrospective cohort Study. 74 patients who had adhesiolysis and hormone therapy for IUA and progressed into the third trimester were group A and 296 without IUA were group B. The main outcome measure is the incidence of placenta related disease including placenta accreta spectrum, placenta previa, placental abruption, intrauterine growth restriction (IUGR), and pregnancy-induced hypertension (PIH). The second outcome is the perinatal, and intrapartum complications. RESULTS: Patients in group A had a higher frequency of prior pregnancy times (2.51 ± 1.56 vs.1.84 ± 1.06, p = 0.001) and lower frequency of prior delivery times (0.20 ± 0.41 vs. 1.30 ± 0.51, p < 0.05) than group B at baseline. At delivery, there is no difference between the incidence of PIH and IUGR between two groups. However, a significantly higher frequency of placenta accreta (17.6% vs. 1.4%, OR = 15.56, 95% CI 4.91-49.34), placenta increta (5.4% vs. 0.7%, OR = 8.4, 95% CI 1.51-46.78), placenta previa (8.1% vs. 2.0%, OR = 4.265, 95%CI1.33-13.63) and postpartum hemorrhage (21.6% vs. 3.4%, OR = 7.890, 95% CI 3.41-18.26) were observed in group A than in group B. CONCLUSIONS: Compared to general population, the rates of placenta accreta, placenta increta, placenta previa, postpartum hemorrhage are higher among the IUA patients after hysteroscopic adhesiolysis, and special attention is needed at the termination of the pregnancy.


Subject(s)
Placenta Diseases/epidemiology , Uterine Diseases/epidemiology , Adult , Case-Control Studies , Cesarean Section/statistics & numerical data , Female , Humans , Incidence , Placenta Diseases/etiology , Pregnancy , Pregnancy Outcome/epidemiology , Retrospective Studies , Tissue Adhesions/complications
11.
Parasitol Res ; 119(6): 1795-1802, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32335727

ABSTRACT

Species of Cosmocerca Diesing, 1861 (Ascaridomorpha: Cosmocercoidea), are common nematode parasites of amphibians. In the present study, a new species of Cosmocerca, namely C. simile n. sp., was described using light and scanning electron microscopy, and sequencing different nuclear and mitochondrial genetic markers (i.e. small ribosomal DNA (18S), large ribosomal DNA (28S), internal transcribed spacer (ITS) and cytochrome c oxidase subunit 1 (cox1)). Cosmocerca simile n. sp. differs from its congeners based on body size, morphology and number of plectanes, relative length of spicules and gubernaculum and spicules to total body length and morphology and length of tail. Molecular analysis showed no nucleotide polymorphisms among different individuals of the new species regarding nuclear DNA. Very low intraspecific nucleotide variation (0.52-0.78%) was detected in cox1 mtDNA. In contrast, the level of interspecific nucleotide variation between C. simile n. sp. and its congeners were distinctly higher (2.74-18.1% in the partial ITS region and 10.2-13.5% in the partial cox1 region, respectively) than that of intraspecific variation. Phylogenetic analyses using maximum likelihood (ML) inference based on the partial ITS and cox1 sequence data both supported the new species to be a member of the genus Cosmocerca, and formed a sister relationship to C. japonica. The newly obtained genetic data are important for further studies of DNA-based taxonomy, population genetics and phylogenetics of the Cosmocercoidea.


Subject(s)
Ascaridida/classification , Bufonidae/parasitology , Phylogeny , Animals , Ascaridida/anatomy & histology , Ascaridida/genetics , Cyclooxygenase 1/genetics , DNA, Helminth/genetics , DNA, Mitochondrial/genetics , DNA, Ribosomal/genetics , Sequence Analysis, DNA , Species Specificity
12.
Infect Genet Evol ; 80: 104172, 2020 06.
Article in English | MEDLINE | ID: mdl-31911143

ABSTRACT

Species of MegalobatrachonemaYamaguti, 1941 (Ascaridida: Cosmocercoidea) are important nematode parasites in amphibians and reptiles. However, the phylogenetic relationship of its included two subgenera Megalobatrachonema and Chabaudgolvania remains unclear. In the present study, a new species of Megalobatrachonema, M. (Chabaudgolvania) wangi sp. nov., was described based on the specimens collected from the lesser spiny frog Quasipaa exilispinosa (Liu & Hu) (Amphibia: Anura) in China. The ribosomal [large ribosomal DNA (28S) and internal transcribed spacer (ITS1-5.8S-ITS2)] and mitochondrial [12S small subunit ribosomal DNA and cytochrome c oxidase subunit 1 (cox1)] target regions of the new species and M. (Chabaudgolvania) terdentatum, together with the 12S region of M. (Megalobatrachonema) hainanensis, were amplified and sequenced for molecular identification and phylogeny. Moreover, in order to clarify the systematic position of the new species and the phylogenetic relationship of the two subgenera Megalobatrachonema and Chabaudgolvania, phylogenetic analyses based on 28S + ITS1-5.8S-ITS2 + 12S sequence data were performed using maximum likelihood (ML) inference and Bayesian inference (BI). The molecular phylogenetic results conflicted with the current classification and challenged the validity of the subgenus Chabaudgolvania, that should be a synonym of the subgenus Megalobatrachonema. The presence or absence of valves in the oesophageal bulb as a key criterion for delimitation of the two subgenera Megalobatrachonema and Chabaudgolvania seems to be unreliable.


Subject(s)
Ascaridida/anatomy & histology , Ascaridida/classification , Ascaridida/genetics , Phylogeny , Animals , Ascaridida/ultrastructure , DNA, Ribosomal , DNA, Ribosomal Spacer , Female , Genes, Helminth , Male
13.
Acta Parasitol ; 64(3): 442-448, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31069646

ABSTRACT

INTRODUCTION: Subulura chinensis Schwartz, 1926 is a hitherto poorly known nematode species. The morphology of S. chinensis has not been sufficiently well described. In addition, the molecular data from species of the Subuluroidea are extremely limited. METHODS: The detailed morphology of S. chinensis was studied using light microscopy and, for the first time, scanning electron microscopy, based on newly collected specimens from the little owl Athene noctua (Scopoli) (Strigiformes: Strigidae) in China. The internal transcribed spacer (ITS) of ribosomal DNA and mitochondrial cytochrome c oxidase subunit 1 (cox1) target regions of S. chinensis were first amplified by polymerase chain reaction (PCR), then sequenced and analysed for the molecular identification of this species. RESULTS: Our SEM observations showed for the fist time the detailed morphology of the cephalic extremity, precloacal pseudo-sucker, caudal papillae, gubernaculum, phasmids and vulva of S. chinensis, and also determined the presence of a small, single medio-ventral precloacal papilla in the male. Moreover, we detected the presence of 0.08-0.40% and 0-1.30% nucleotide divergence among different individuals of S. chinensis in the ITS and cox1 regions, respectively. The supplementary morphological characters and genetic data will be very useful for the diagnosis of this poorly known species.


Subject(s)
Ascaridida Infections/veterinary , Ascaridida/isolation & purification , Bird Diseases/parasitology , Strigiformes/parasitology , Animals , Ascaridida/classification , Ascaridida/genetics , Ascaridida/ultrastructure , Ascaridida Infections/parasitology , China , DNA, Helminth/genetics , DNA, Ribosomal/genetics , Female , Male , Microscopy, Electron, Scanning
14.
Parasit Vectors ; 11(1): 274, 2018 05 02.
Article in English | MEDLINE | ID: mdl-29716661

ABSTRACT

BACKGROUND: The whitespotted conger Conger myriaster (Brevoort) (Anguilliformes: Congridae) is an extremely marketable food fish, commonly consumed as sashimi or sushi in some Asian countries (i.e. Japan, Korea and China). Conger myriaster is also suspected as being an extremely important source of human anisakidosis. However, there is currently very little information on the levels of infection with ascaridoid nematode parasites in this economically important marine fish. The aims of the present study are to determine the species composition, prevalence and mean intensity of ascaridoid parasites of C. myriaster caught in the Zhoushan Fishery. RESULTS: A total of 1142 third-stage ascaridoid larvae were isolated from 204 C. myriaster. The overall prevalence of infection was 100% (mean intensity 5.6). Nine species of such larvae were accurately identified using integrative taxonomic techniques involving both morphological and genetic data; these included Anisakis pegreffii, A. typica and A. simplex (sensu stricto) × A. pegreffii, Hysterothylacium fabri, H. aduncum, H. sinense, H. amoyense, H. zhoushanense and Raphidascaris lophii. Although high levels of infection and species richness were revealed in C. myriaster, most of the ascaridoid parasites (1135 individuals) were collected from the body cavity and visceral organs of the fish and only seven individuals of A. pegreffii were found in the musculature. CONCLUSIONS: This study represents the first report C. myriaster from the Zhoushan Fishery being heavily infected with third-stage ascaridoid larvae. Among the ascaridoid larvae parasitic in this fish, an important etiological agent of human anisakidosis, A. pegreffii (L3), represents the predominant species. The genus Hysterothylacium has the highest species richness, with H. fabri (L3) being the most prevalent species. This high level of infection of A. pegreffii (L3) in C. myriaster suggests a high risk of anisakidosis or associated allergies for people consuming raw or poorly cooked fish originating from this marine area. These findings provide important basic information on the occurrence and infection parameters of ascaridoid nematodes in this economically important marine fish. They also have significant implications for the prevention and control of human anisakidosis when conger eels from the Zhoushan Fishery are consumed.


Subject(s)
Ascaridida Infections/veterinary , Ascaridoidea/classification , Ascaridoidea/isolation & purification , Biodiversity , Eels/parasitology , Fish Diseases/epidemiology , Fish Diseases/parasitology , Animals , Ascaridida Infections/epidemiology , Ascaridida Infections/parasitology , China , Fisheries , Parasite Load
15.
Parasitol Res ; 117(6): 1857-1864, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29680942

ABSTRACT

A new cosmocercid species, Cosmocercoides qingtianensis sp. n., collected from the intestine of the Asiatic toad Bufo gargarizans Cantor (Amphibia: Anura) is described using integrated approaches, including light and scanning electron microscopy, and sequencing and analyzing the ribosomal [small ribosomal DNA (18S) and internal transcribed spacer (ITS)] and mitochondrial [cytochrome c oxidase subunit 1 (cox1)] target regions, respectively. The new species can be distinguished from its congeners by the combination of the following morphological characters, including the large body size, the presence of lateral alae and somatic papillae in both sexes, the length of spicules, the particular morphology and length of gubernaculum, the number, arrangement and morphology of caudal rosettes, the presence of large medioventral precloacal papilla and the long tail. Our molecular analysis revealed the level of intraspecific genetic variation of C. qingtianensis sp. n. distinctly lower than that of the interspecific genetic variation in the ITS and cox1 regions. However, there are some overlaps in the range of intra- and interspecific 18S sequence divergence between the new species and some closely related species. The results of molecular analysis supported the validity of the new species based on the morphological observations. The 18S, ITS, and cox1 regions of C. pulcher collected from Bufo japonicus formosus in Japan were also sequenced and analyzed. The results showed a low level of intraspecific genetic variation in 18S and ITS regions (0-0.12% and 0-0.23% nucleotide differences, respectively), but a relatively high level of intraspecific genetic variation in cox1 region (0.78-4.69% nucleotide differences). In addition, it seems more powerful and practical to use the cox1 region as a genetic marker for the accurate identification and differentiation of species of Cosmocercoides than the 18S and ITS regions, especially for the closely related species.


Subject(s)
Ascaridida/classification , Ascaridida/genetics , Bufonidae/parasitology , Animals , Ascaridida/isolation & purification , DNA, Intergenic/genetics , DNA, Ribosomal/genetics , Electron Transport Complex IV/genetics , Female , Genetic Variation/genetics , Intestines/parasitology , Japan , Male , Microscopy, Electron, Scanning , RNA, Ribosomal, 18S/genetics
16.
Syst Biol ; 67(5): 888-900, 2018 09 01.
Article in English | MEDLINE | ID: mdl-29528459

ABSTRACT

Ascaridoids are among the commonest groups of zooparasitic nematodes (roundworms) and occur in the alimentary canal of all major vertebrate groups, including humans. They have an extremely high diversity and are of major socio-economic importance. However, their evolutionary history remains poorly known. Herein, we performed a comprehensive phylogenetic analysis of the Ascaridoidea. Our results divided the Ascaridoidea into six monophyletic major clades, i.e., the Heterocheilidae, Acanthocheilidae, Anisakidae, Ascarididae, Toxocaridae, and Raphidascarididae, among which the Heterocheilidae, rather than the Acanthocheilidae, represents the sister clade to the remaining ascaridoids. The phylogeny was calibrated using an approach that involves time priors from fossils of the co-evolving hosts, and dates the common ancestor of the Ascaridoidea back to the Early Carboniferous (approximately 360.47-325.27 Ma). The divergence dates and ancestral host types indicated by our study suggest that members of the Ascaridoidea first parasitized terrestrial tetrapods, and subsequently, extended their host range to elasmobranchs and teleosts. We also propose that the fundamental terrestrial-aquatic switches of these nematodes were affected by changes in sea-level during the Triassic to the Early Cretaceous.


Subject(s)
Ascaridoidea/genetics , Biological Evolution , Phylogeny , Animals , Ascaridoidea/classification , Evolution, Molecular , Genes, Mitochondrial
17.
Acta Parasitol ; 63(1): 154-159, 2018 Mar 26.
Article in English | MEDLINE | ID: mdl-29351063

ABSTRACT

Seuratascaris numidica (Seurat, 1917) is a specialized nematode species parasitizing amphibians only. In the present study, the detailed morphology of this poorly known species was studied using light and scanning electron microscopy based on the newly material collected from Hoplobatrachus chinensis (Osbeck) (Amphibia: Anura) in China. We found that the relative length of intestinal caecum in our male specimens (representing 68.4-71.1% of oesophageal length) is slighter longer than the previously reported data (not over 60.0% of oesophageal length). Our SEM observations also revealed the presence of ca. 64-76 small conical denticles on each lip. In addition, Angusticaecum wuyiensis Wang, 1981, collected from Rana schmackeri Boettger (Amphibia: Anura) from Wuyi Mountain in Fujian Province, China was considered as a new synonym of S. numidica. The ITS and cox1 sequences of S. numidica were also sequenced for the first time and there is no nucleotide variability detected in both regions. The present supplementary morphological and molecular data (especially the ITS and cox1 sequences) obtained herein is extremely important and useful to determine the morphological variability, population genetics and phylogenetic position of S. numidica in the future.


Subject(s)
Anura/parasitology , Ascaridoidea/anatomy & histology , Ascaridoidea/genetics , Animal Structures/anatomy & histology , Animals , Ascaridoidea/classification , Ascaridoidea/isolation & purification , Biometry , China , Cluster Analysis , DNA, Helminth/chemistry , DNA, Helminth/genetics , DNA, Ribosomal Spacer/chemistry , DNA, Ribosomal Spacer/genetics , Male , Microscopy , Microscopy, Electron, Scanning , Phylogeny , Sequence Analysis, DNA
18.
ACS Appl Mater Interfaces ; 9(40): 34783-34792, 2017 Oct 11.
Article in English | MEDLINE | ID: mdl-28906101

ABSTRACT

Sulfur was impregnated into hyper-cross-linked porous polymer (HCP) with a high specific area and unique porous structure. Compared to its inorganic or carbon counterparts, the HCP has a relatively high specific surface area of 1980 m2 g-1 with a total pore volume of 2.61 cm3 g-1, resulting in sulfur content in HCP/S of as high as 80 wt %. As a benefit of the unique HCP structure, the HCP/S composite exhibits a high initial discharge specific capacity (1333 mA h g-1 at 0.2 C), high-rate property, and good cycling stability (658 mA h g-1 after 120 cycles at 0.5 C and 604 mA h g-1 after 80 cycles at 1 C). Furthermore, the capacity of cells loses less than 1% after the first 20 charge/discharge cycles, while the HCP/S cathode can be cycled with an excellent Coulombic efficiency of above 94% after 120 cycles. Compared with pristine sulfur, the superior electrochemical performance of HCP/S composite is related to the cross-linked porous framework. Such structure could provide short ionic/electronic conduction pathways and suppress the polysulfide shuttle during the discharge process.

19.
Oncol Lett ; 14(1): 615-622, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28693213

ABSTRACT

A series of antibodies against vascular endothelial growth factor (VEGF) have been developed for the treatment of various types of cancer, including non-small cell lung cancer (NSCLC) in recent years. However, tumors frequently demonstrate resistance to these strategies of VEGF inhibition. Efforts to better understand the mechanism underlying the acquired resistance to anti-VEGF antibodies are warranted. In the present study, in order to develop a xenograft model of acquired resistance to anti-VEGF antibody, xenografts of human adenocarcinoma A549 cells were generated through the successive inoculation of tumor tissue explants into first (F1), second (F2) and third (F3) generations of mice treated with the anti-VEGF antibody B20. Tumor growth rate and vessel-forming ability, assessed via cluster of differentiation (CD) 31 staining, were significantly lower in the F1, F2 and F3 groups compared with in the F0 control group (P<0.01), suggesting that drug resistance was not successfully acquired. The percentages of CD11b+ myeloid-derived suppressor cells and lymphocyte antigen 6C (Ly6C)+ subsets were significantly smaller in F1, F2 and F3 groups compared with in F0 (P<0.01). However, the ratio of Ly6C+ to CD11b+ cells was significantly higher in the F3 group compared with in F0 and F1 groups (P<0.01), indicating increasing recruitment of the Ly6C+ subset with successive challenges with the anti-VEGF antibody. In conclusion, the recruitment of CD11b+Ly6C+ monocytes increased with successive generations of NSCLC-xenografted mice challenged by B20, an anti-VEGF agent.

20.
Acta Parasitol ; 62(3): 575-581, 2017 Sep 26.
Article in English | MEDLINE | ID: mdl-28682762

ABSTRACT

Durettenema guangdongense gen. et sp. nov. is described from Hipposideros larvatus (Horsfield) (Chiroptera: Rhinolophidae) in Guangdong Province, China. The new genus differs from the other genera of subfamily Molineinae in the structure of the synlophe, the absence of lateral alae, the arrangement of the bursa rays, the shape of the spicules, the female tail and the presence of gubernaculum. Meanwhile, considering the morphological characters of Macielia rhinolophi Yin, 1980, including the pattern of the bursa ray, the shape of the spicules, and the female tail, this species should be transferred to the genus Durettenema, as D. rhinolophi (Yin, 1980) comb. nov., which can be distinguished from D. guangdongense in the shape of the ovejector. In addition, the ITS-1 sequences of D. guangdongense were also analysed, these sequence added new data for the molecular diagnosis of trichostrongylid nematodes.


Subject(s)
Chiroptera/parasitology , Molineoidae/classification , Molineoidae/ultrastructure , Strongylida Infections/veterinary , Animals , Female , Male , Species Specificity , Strongylida Infections/parasitology
SELECTION OF CITATIONS
SEARCH DETAIL
...