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1.
Opt Lett ; 49(6): 1616-1619, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489465

RESUMO

The S fiber taper (SFT) aptasensor with a composite sensitive membrane of graphene oxide and gold nanoparticles was proposed for the rapid and highly sensitive detection of bisphenol A (BPA). The SFT was obtained using a fusion splicer; subsequently, the composite film was deposited on its surface, and the specific aptamer was covalently bonded to the surface of gold nanoparticles. The detection mechanism relies on monitoring changes in the external refractive index induced by the specific binding of BPA to the aptamer. The developed SFT aptasensor exhibited a remarkable sensitivity of 15.5 nm/nM and a limit of detection as low as 0.01 nM for BPA. These findings highlight the aptasensor's potential for diverse monitoring applications.

2.
J Org Chem ; 88(24): 17227-17236, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38019169

RESUMO

This study presents a convenient approach to the synthesis of indole- and benzofuran-based benzylic sulfones using unactivated alkynes containing aryl iodides and sodium sulfinates under visible light irradiation. The procedure involves a sequential series of dehalogenation, carbo-cyclization, and radical sulfonylation. Plausible insights into the reaction mechanism are derived from control experiments, leading to the proposal of a radical cascade reaction pathway.

3.
Phys Chem Chem Phys ; 25(12): 8676-8683, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36892054

RESUMO

Exploring two-dimensional (2D) van der Waals materials with out-of-plane polarization and electromagnetic coupling is essential for the development of next-generation nano-memory devices. A novel class of 2D monolayer materials with predicted spin-polarized semi-conductivity, partially compensated antiferromagnetic (AFM) order, fairly high Curie temperature, and out-of-plane polarization is analyzed in this work for the first time. Based on density functional theory calculations, we systematically studied these properties in asymmetrically functionalized MXenes (Janus Mo2C)-Mo2CXX' (X, X' = F, O, and OH). Using ab initio molecular dynamics (AIMD) and phonon spectrum calculations, the thermal and dynamic stabilities of six functionalized Mo2CXX' were identified. Our DFT+U calculation results also provided a switching path for out-of-plane polarizations, where the reverse of electric polarization is driven by terminal-layer atom flipping. More importantly, strong coupling between magnetization and electric polarization originating from spin-charge interactions was observed in this system. Our results confirm that Mo2C-FO would be a novel monolayer electromagnetic material, and its magnetization can be modulated by electric polarization.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38064628

RESUMO

Background: Impaired cardiac microvascular function has been implied in the pathophysiology of diabetic cardiovascular disease. However, the specific mechanism remains to be determined. Pyroptosis is a type of cell death that differs from apoptosis and autophagy. It is caused by the formation of plasma membrane pores through amino-terminal fragments of Gasdermin D (GSDMD), leading to the secretion of IL-1ß and IL-18. Recent studies have shown that irisin, a myokine cleaved by the extracellular domain of FNDC5, plays a protective role in cardiovascular diseases. Here, we investigated the potential role of pyroptosis on the cardiac microvascular endothelial cells (CMECs) injury induced by high glucose (HG) and further determined the protective effect of irisin on pyroptosis. Methods: CMECs were cultured with normal glucose (control group, 5.5 mM) and high glucose (25 mM) medium for 12, 24, and 48 h respectively. The pyroptosis of CMECs was measured by immunofluorescence staining, ELISA, and Western blot assays. Moreover, the apoptosis level was determined by flow cytometry and TUNEL staining. Results: Our results showed that HG promoted apoptosis and pyroptosis. However, irisin reversed the increased apoptosis and pyroptosis. To investigate the underlying mechanism, we overexpressed the NLRP3 protein. We found the protective effect of irisin on apoptosis and pyroptosis was abolished by NLRP3 over-expression. Conclusions: Our data suggest that irisin protects CMECs against apoptosis and pyroptosis, at least in part, by inhibiting NLRP3 inflammasome.

5.
Microcirculation ; 29(8): e12786, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36151930

RESUMO

PURPOSE: NLRP3 inflammasome mediates myocardial ischemia/reperfusion (MI/R) injury and diabetic vascular endothelia dysfunction. However, the role of NLRP3 inflammasome in MI/R injury with diabetes has not been fully described. Irisin plays an important role in anti-inflammation and improves endothelial function in type 2 diabetes. The current study aimed to investigate the effect of irisin on regulating NLRP3 inflammasome activation in diabetic vascular endothelia dysfunction. METHODS: Cardiac microvascular endothelial cells (CMECs) were cultured and subjected to high glucose/high fat (HG/HF) receiving hypoxia/reoxygenation (H/R) with irisin incubation or not. Then, apoptosis, viability, migration, NO secretion, and inflammasome activation were examined. RESULTS: The hypoxic CMECs exhibited increased apoptosis, impaired viability, and migration, even decreased NO secretion and enhanced inflammasome activation. Moreover, irisin incubation decreased NLRP3 activation and attenuated cell injury in HG/HF cultured CMECs subjected to H/R injury, which was abolished by NLRP3 inflammasome activation. Meanwhile, NLRP3 inflammasome siRNA also attenuated H/R injury in CMECs under HG/HF condition. CONCLUSION: The current study demonstrated for the first time that irisin inhibits NLRP3 inflammasome activation in CMECs as a novel mechanism in myocardial ischemia/reperfusion injury in diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Traumatismo por Reperfusão Miocárdica , Traumatismo por Reperfusão , Humanos , Inflamassomos/farmacologia , Células Endoteliais , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Fibronectinas/farmacologia
6.
Phys Rev Lett ; 129(21): 213602, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36461956

RESUMO

A new Fano profile of a flat line is achieved experimentally by manipulating the relative amplitude of the continuum path, when q takes the pure imaginary number of -i in the x-ray regime. The underlying mechanism is that the interference term in the scattering will cancel the discrete term exactly. This new Fano profile renders only an observable continuum along with an invisible response to the discrete state of atomic resonance. The results suggest not only a different strategy to invisibility studies which provides a possible tool to identify weaker structures hidden by the strong white line, but also a new scenario to enrich the manipulations of two-path interference and nonlinear Fano resonance.

7.
Cladistics ; 38(4): 452-464, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35349189

RESUMO

Arachnida is an exceptionally diverse class in the Arthropoda, consisting of 20 orders and playing crucial roles in the terrestrial ecosystems. However, their interordinal relationships have been debated for over a century. Rearranged or highly rearranged mitochondrial genomes (mitogenomes) were consistently found in this class, but their various extent in different lineages and efficiency for resolving arachnid phylogenies are unclear. Here, we reconstructed phylogenetic trees using mitogenome sequences of 290 arachnid species to decipher interordinal relationships as well as diversification through time. Our results recovered monophyly of ten orders (i.e. Amblypygi, Araneae, Ixodida, Mesostigmata, Opiliones, Pseudoscorpiones, Ricinulei, Sarcoptiformes, Scorpiones and Solifugae), while rejecting monophyly of the Trombidiformes due to the unstable position of the Eriophyoidea. The monophyly of Acari (subclass) was rejected, possibly due to the long-branch attraction of the Pseudoscorpiones. The monophyly of Arachnida was further rejected because the Xiphosura nested within arachnid orders with unstable positions. Mitogenomes that are highly rearranged in mites but less rearranged or conserved in the remaining lineages point to their exceptional diversification in mite orders; however, shared derived mitochondrial (mt) gene clusters were found within superfamilies rather than interorders, confusing phylogenetic signals in arachnid interordinal relationships. Molecular dating results show that arachnid orders have ancient origins, ranging from the Ordovician to the Carboniferous, yet have significantly diversified since the Cretaceous in orders Araneae, Mesostigmata, Sarcoptiformes, and Trombidiformes. By summarizing previously resolved key positions of some orders, we propose a plausible arachnid tree of life. Our results underline a more precise framework for interordinal phylogeny in the Arachnida and provide new insights into their ancient evolution.


Assuntos
Aracnídeos , Genoma Mitocondrial , Ácaros , Animais , Aracnídeos/genética , Ecossistema , Genoma Mitocondrial/genética , Filogenia
8.
Cell Biol Int ; 46(5): 723-736, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35032153

RESUMO

Myocardial infarction is characterized by cardiomyocyte death and mitochondrial dysfunction induced by ischemia. Ferroptosis, a novel form of cell death, has been found to play critical roles under ischemic conditions. Recently, several studies have shown that fibronectin type III domain-containing 5 (FNDC5) and its cleaved form, irisin, protect the heart against injury. However, its protective effect on ferroptosis and mitochondrial impairments is still unclear. Thus, our aim was to investigate the role of irisin in ferroptosis and mitochondrial dysfunction in cardiomyocytes under hypoxic conditions. Cardiomyocytes were treated with FNDC5 overexpression and/or irisin under normoxic and hypoxic conditions. Cell viability was assessed by Cell Counting Kit-8 assay. Reactive oxygen species production was evaluated by dihydroethidium staining. In addition, the intracellular ferrous iron level (Fe2+ ) and the relative concentration of malondialdehyde and ATP content were determined using an Iron Assay Kit, Lipid Peroxidation Assay Kit, and ATP Bioluminescent Assay Kit. The superoxide dismutase level in cells was measured using an Enzyme-Linked Immunosorbent Assay Kit. Furthermore, an immunoblotting assay was used to determine ferroptosis-related mitochondrial proteins. Hypoxia promoted cell death, increased ferroptosis, and caused mitochondrial dysfunction in cardiomyocytes. Interestingly, FNDC5 overexpression and/or irisin administration elevated cell viability, decreased ferroptosis, and reversed mitochondrial impairments induced by hypoxia. Mechanistically, FNDC5/irisin reduced ferroptosis and reversed mitochondrial impairments by Nrf2/HO-1 axis in hypoxic cardiomyocytes. Thus, we have demonstrated that FNDC5/irisin plays a protective role in ferroptosis and mitochondrial dysfunction in hypoxia-induced cardiomyocytes.


Assuntos
Ferroptose , Miócitos Cardíacos , Trifosfato de Adenosina/metabolismo , Apoptose , Fibronectinas/metabolismo , Humanos , Hipóxia/metabolismo , Ferro/metabolismo , Mitocôndrias/metabolismo , Miócitos Cardíacos/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Transdução de Sinais
9.
Parasitol Res ; 121(10): 2841-2848, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35939147

RESUMO

Tetratrichomonas gallinarum and Trichomonas gallinae can colonize the alimentary tract of domestic birds. However, little information is available on the epidemiology of the two trichomonad species in domestic free-range poultry in China. In this study, the occurrence and genetic characteristic of T. gallinarum and T. gallinae among free-range chickens, ducks, and geese in Anhui Province, China, were investigated. The 1910 fecal samples collected from 18 free-range poultry farms throughout Anhui Province were examined for the presence of T. gallinarum and T. gallinae by PCR and sequence analysis of the small subunit (SSU) rRNA gene of T. gallinarum and ITS1-5.8S-ITS2 sequence of T. gallinae. The overall occurrence of T. gallinarum in poultry was 1.2% (22/1910), with infection rates of 2.1% (17/829) in chickens, 0.2% (1/487) in ducks, and 0.7% (4/594) in geese. The constructed phylogeny tree using the concatenated ITS1-5.8S-ITS2 region and SSU rRNA indicated the T. gallinarum isolates detected in this study were closely related to previously defined genogroups A, D, and E, respectively. Nine (0.5%) fecal samples were positive for T. gallinae, with infection rates of 0.8% (7/829) in chickens, 0.4% (2/487) in ducks, and 0% (0/594) in geese. Sequence and phylogenetic analysis showed that four T. gallinae ITS1-5.8S-ITS2 sequences obtained from chicken feces and one duck fecal sample belonged to genotype ITS-OBT-Tg-1. This is the first report of the prevalence and genetic characterization of T. gallinarum and T. gallinae in free-range chickens, ducks, and geese in China.


Assuntos
Doenças das Aves , Trichomonadida , Tricomoníase , Trichomonas , Animais , Doenças das Aves/epidemiologia , Galinhas , Patos , Filogenia , Aves Domésticas , Prevalência , Trichomonas/genética , Tricomoníase/epidemiologia , Tricomoníase/veterinária
10.
BMC Genomics ; 22(1): 243, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33827435

RESUMO

BACKGROUND: Altica (Coleoptera: Chrysomelidae) is a highly diverse and taxonomically challenging flea beetle genus that has been used to address questions related to host plant specialization, reproductive isolation, and ecological speciation. To further evolutionary studies in this interesting group, here we present a draft genome of a representative specialist, Altica viridicyanea, the first Alticinae genome reported thus far. RESULTS: The genome is 864.8 Mb and consists of 4490 scaffolds with a N50 size of 557 kb, which covered 98.6% complete and 0.4% partial insect Benchmarking Universal Single-Copy Orthologs. Repetitive sequences accounted for 62.9% of the assembly, and a total of 17,730 protein-coding gene models and 2462 non-coding RNA models were predicted. To provide insight into host plant specialization of this monophagous species, we examined the key gene families involved in chemosensation, detoxification of plant secondary chemistry, and plant cell wall-degradation. CONCLUSIONS: The genome assembled in this work provides an important resource for further studies on host plant adaptation and functionally affiliated genes. Moreover, this work also opens the way for comparative genomics studies among closely related Altica species, which may provide insight into the molecular evolutionary processes that occur during ecological speciation.


Assuntos
Besouros , Sifonápteros , Animais , Besouros/genética , Evolução Molecular , Genoma , Genômica
11.
J Invertebr Pathol ; 181: 107591, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33882275

RESUMO

Wolbachia are common intracellular endosymbionts of arthropods, but the interactions between Wolbachia and arthropods are only partially understood. The fruit fly Drosophila melanogaster is a model insect for understanding Wolbachia-host interactions. Here the native wMel strain of D. melanogaster was isolated and then different initial titres of wMel were artificially transferred back into antibiotics-treated fruit flies. Our purpose was to examine the interactions between the injected wMel in a density gradient and the recipient host during trans-generational transmission. The results showed that the trans-generational transmission rates of wMel and titres of wMel exhibited a fluctuating trend over nine generations, and the titres of wMel displayed a similar fluctuating trans-generational trend. There was a significant positive correlation between the transmission rate and the titre of wMel. Reciprocal crossings between wMel-transinfected and uninfected fruit flies revealed that wMel could induce cytoplasmic incompatibility (CI) at different initial titres, but the intensity of CI was not significantly correlated with the initial titre of wMel. Quantitative PCR analysis showed that the immune genes Drsl5 and Spn38F displayed a significant transcriptional response to wMel transfection, with an obvious negative correlation with the titre of wMel at the 3rd and 4th generations. Furthermore, RNA interference-mediated knockdown of Drsl5 and Spn38F elicited a drastic increase in the titre of wMel. In combination, our study suggests that the trans-generational transmission of wMel is modulated by its density, and the immune genes are involved in the regulation of Wolbachia density.


Assuntos
Drosophila melanogaster/imunologia , Wolbachia/fisiologia , Animais , Drosophila melanogaster/genética
12.
Parasitol Res ; 120(10): 3519-3527, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34417865

RESUMO

Free-range chickens might mediate the spread of Cryptosporidium oocysts to humans and other animals. Few studies have evaluated the prevalence of Cryptosporidium species in domestic free-range poultry in China. Here, we characterized the prevalence and distribution of species and genotypes of Cryptosporidium in domestic free-range chickens, ducks, and geese in Anhui Province, China. A total of 1910 fresh fecal samples from three poultry species were examined from 18 free-range poultry farms by nested PCR and analysis of the Cryptosporidium SSU rRNA gene. The overall prevalence of Cryptosporidium species was 2.9% (55/1910), with infection rates of 1.3% (11/829) in chickens, 7.3% (36/487) in ducks, and 1.4% (8/594) in geese. C. baileyi (0.6%), C. meleagridis (0.2%), C. galli (0.2%), and C. xiaoi-like genotype (0.2%) were identified in chickens, and only C. baileyi was identified in ducks and geese, with infection rates of 7.4% and 1.3%, respectively. C. baileyi was the most prevalent species. Sequencing of the GP60 gene revealed that the C. meleagridis isolates belonged to the IIIbA26G1R1b subtype. This is the first study to document C. galli and C. xiaoi-like genotype in domestic free-range chickens in China. These findings expand the range of avian hosts known for Cryptosporidium and highlight the need for additional studies to characterize the diversity of Cryptosporidium in avian species.


Assuntos
Criptosporidiose , Cryptosporidium , Doenças das Aves Domésticas , Animais , Galinhas , China/epidemiologia , Criptosporidiose/epidemiologia , Cryptosporidium/genética , Fezes , Genótipo , Humanos , Aves Domésticas , Doenças das Aves Domésticas/epidemiologia , Prevalência
13.
Cancer Immunol Immunother ; 69(11): 2333-2343, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32514618

RESUMO

Patients with pediatric cancers such as neuroblastoma (NB) are often unresponsive to checkpoint blockade immunotherapy. One major factor in pediatric tumor resistance to immunotherapy is considered to be the low mutation rate of pediatric tumors. Another factor may be the overexpression of additional inhibitory pathways. While analyzing the RNA-sequencing database TARGET, we found that human NB tumors overexpress immune checkpoint molecule CD200. To determine its significance and impact on tumor immune microenvironment, we analyzed 49 cases of previously untreated, surgically removed NB tumors using immunohistochemistry and multi-color flow cytometry (FACS). We found that CD200 is overexpressed in more than 90% of NB tumors. In the tumor microenvironment of NB, CD200 is mainly overexpressed in CD45- NB tumor cells, while its cognate receptor (CD200R) is mainly expressed in HLA-DR+CD14+ myeloid cells and CD11c+ dendritic cells. Low-level expression of CD200R is also observed in tumor-infiltrating CD4+ and CD8+ T cells. In NB tumors with higher CD200 expression (CD200high), we observed lower numbers of HLA-DR+CD14+ myeloid cells and less tumor-infiltrating CD4+ and CD8+ T cells. Moreover, we found that CD4+ and CD8+ T cells produced less IFN-γ and/or TNF-α in CD200high NB tumors. Thus, CD200-CD200R pathway appears to downregulate anti-tumor immunity in the tumor microenvironment of NB tumors, and blockade of this pathway may be beneficial for NB patients.


Assuntos
Antígenos CD/imunologia , Linfócitos do Interstício Tumoral/imunologia , Neuroblastoma/imunologia , Microambiente Tumoral/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Receptores de Orexina/imunologia , Evasão Tumoral/imunologia
14.
J Anim Ecol ; 89(5): 1262-1276, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32124424

RESUMO

Functional traits are the essential phenotypes that underlie an organism's life history and ecology. Although biologists have long recognized that intraspecific variation is consequential to an animals' ecology, studies of functional variation are often restricted to species-level comparisons, ignoring critical variation within species. In birds, interspecific comparisons have been foundational in connecting flight muscle phenotypes to species-level ecology, but intraspecific variation has remained largely unexplored. We asked how age- and sex-dependent demands on flight muscle function are reconciled in birds. The flight muscle is an essential multifunctional organ, mediating a large range of functions associated with powered flight and thermoregulation. These functions must be balanced over an individual's lifetime. We leveraged within- and between-species comparisons in a clade of small passerines (Tarsiger bush-robins) from the eastern edge of the Qinghai-Tibet Plateau. We integrated measurements of flight muscle physiology, morphology, behaviour, phenology and environmental data, analysing trait data within a context of three widespread, adaptive life-history strategies-sexual dichromatism, age and sex-structured migration, and delayed plumage maturation. This approach provides a framework of the selective forces that shape functional variation within and between species. We found more variation in flight muscle traits within species than has been previously described between species of birds under 20 g. This variation was associated with the discovery of mixed muscle fibre types (i.e. both fast glycolytic and fast oxidative fibres), which differ markedly in their physiological and functional attributes. This result is surprising given that the flight muscles of small birds are generally thought to contain only fast oxidative fibres, suggesting a novel ecological context for glycolytic muscle fibres in small birds. Within each species, flight muscle phenotypes varied by age and sex, reflecting the functional demands at different life-history stages and the pressures that individuals face as a result of their multi-class identity (i.e. species, age and sex). Our findings reveal new links between avian physiology, ecology, behaviour and life history, while demonstrating the importance of demographic-dependent selection in shaping functional phenotypic variation.


Assuntos
Características de História de Vida , Animais , Voo Animal , Músculos , Fenótipo , Plantas , Tibet
15.
J Chem Phys ; 152(3): 034304, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31968971

RESUMO

For the inelastic electron scattering of atoms and molecules, a consensus has been reached that the first Born approximation is easily approached by decreasing the momentum transfer at the same impact electron energy or increasing the impact electron energy at the same momentum transfer. Although this consensus is applicable for the elastic electron scattering of most atoms and molecules, it is violated for helium where the experimental differential cross sections deviate from the first Born approximation prediction gradually with the decrease of squared momentum transfer at the same impact electron energy. Since this anomalous phenomenon was observed more than 40 years ago, the intrinsic mechanism is not explicit. In the present work, using the high-resolution x-ray scattering, we isolate the scattering contribution from the nucleus and directly obtain the pure electronic structure of helium. Then, the anomalous asymptotic behavior of the elastic electron scattering of helium has been elucidated, i.e., in the small squared momentum transfer region, the scattering contribution from the target's electrons is counteracted by the one from the atomic nucleus, which results in the residual contribution beyond the first Born approximation being drastically enlarged.

16.
Biosci Biotechnol Biochem ; 84(6): 1160-1167, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32125225

RESUMO

Endometrial cancer (EC) is generally considered as a disease that affects older women. We attempt to explore the role of actin­like protein 8 (ACTL8) in EC and how it achieves its function. Based on the data from The Cancer Genome Atlas (TCGA), we found that ACTL8 expression was up-regulated in EC tissues and correlated with shorter overall survival of EC patients. ACTL8 expression was significantly associated with age, clinical-stage, or grade. Cox proportional hazards model analysis revealed that ACTL8 expression, grade, and clinical-stage were promising independent prognostic factors of EC. Knockdown of ACTL8 repressed the proliferative, migrating and invading capabilities of human EC cell lines KLE and Ishikawa. Silencing ACTL8 up-regulated the negative cell cycle regulator p21 and epithelial marker E-cadherin, and down-regulated the positive cell cycle regulator Cyclin A, mesenchymal markers MMP-9 and N-cadherin in KLE cells. Collectively, these outcomes illustrated that ACTL8 might act as a tumor facilitator during EC progression.


Assuntos
Actinas/metabolismo , Biomarcadores Tumorais/metabolismo , Proteínas do Citoesqueleto/metabolismo , Progressão da Doença , Neoplasias do Endométrio/metabolismo , Actinas/genética , Antígenos CD/metabolismo , Biomarcadores Tumorais/genética , Caderinas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Sobrevivência Celular/genética , Ciclina A/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Proteínas do Citoesqueleto/genética , Regulação para Baixo/genética , Neoplasias do Endométrio/patologia , Feminino , Técnicas de Silenciamento de Genes , Humanos , Metaloproteinase 9 da Matriz/metabolismo , Pessoa de Meia-Idade , Prognóstico , Transdução de Sinais/genética , Transfecção , Regulação para Cima/genética
17.
Curr Microbiol ; 77(9): 2441-2448, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32506239

RESUMO

Wolbachia is capable of regulating host reproduction, and thus of great significance in preventing the spread of insect-borne diseases and controlling pest insects. The fruit fly Drosophila melanogaster is an excellent model insect for understanding Wolbachia-host interactions. Here we artificially transferred the wCcep strain from the rice moth Corcyra cephalonica into D. melanogaster by microinjection. Crossing experiments indicated that wCcep could induce a high level of CI in the phylogenetically distant host D. melanogaster and imposed no negative fitness costs on host development and fecundity. Based on quantitative analysis, the titres of wCcep and the native wMel strain were negatively correlated, and wCcep could only be transmitted in the novel host for several generations (G0 to G4) after transinfection. Transcriptome sequencing indicated that the invading wCcep strain induced a significant immune- and stress-related response from the host. An association analysis between the expression of immune genes attacin-D/edin and the titre of Wolbachia by linear regression displayed a negative correlation between them. Our study suggest that the intrusion of wCcep elicited a robust immune response from the host and incurred a competitive exclusion from the native Wolbachia strain, which resulted in the failure of its establishment in D. melanogaster.


Assuntos
Mariposas , Wolbachia , Animais , Drosophila melanogaster , Simbiose , Wolbachia/genética
18.
Parasitol Res ; 119(2): 637-647, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31823007

RESUMO

The trichomonad species Tetratrichomonas buttreyi and Pentatrichomonas hominis have been reported in the bovine digestive tract in only a few studies, and the prevalence and pathogenicity of these two protists in cattle herds remain unknown. In this study, the prevalence of T. buttreyi and P. hominis in yellow cattle, dairy cattle, and water buffalo in Anhui Province, China, was determined with a PCR analysis of the small subunit ribosomal RNA genes. The overall infection rates for T. buttreyi and P. hominis were 8.1% and 5.4%, respectively. Double infections were found in 15 (1.6%) samples from four farms. The prevalence of P. hominis in cattle with abnormal feces was significantly higher than that in cattle with normal feces (χ2 = 13.0, p < 0.01), and the prevalence of T. buttreyi in the northern region of Anhui Province was also significantly higher than that in the mid region (χ2 = 16.6, p < 0.01). Minor allelic variations were detected in the T. buttreyi isolates from cattle in this study, as in other hosts in previous studies. Morphological observations, together with the PCR analysis, demonstrated that the trichomonads isolated in this study were P. hominis. The presence of T. buttreyi and P. hominis indicated that cattle are natural hosts of these two trichomonads and could be a potential source of P. hominis infections in humans and other animal hosts.


Assuntos
Búfalos/parasitologia , Doenças dos Bovinos/parasitologia , Infecções Protozoárias em Animais/epidemiologia , Trichomonadida/genética , Animais , Bovinos , China/epidemiologia , Fezes , Trato Gastrointestinal/parasitologia , Humanos , Prevalência , RNA Ribossômico 18S/genética , Trichomonadida/classificação , Trichomonadida/isolamento & purificação
19.
Parasitol Res ; 119(7): 2359-2362, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32500368

RESUMO

Several Cryptosporidium species that infect reptiles, especially squamates, are well described, but there is limited data about Cryptosporidium species infecting crocodilians. In this study, we assess the occurrence of intestinal parasites using traditional microscopic examination and describe the prevalence and Cryptosporidium species in the captive-bred Chinese alligators (Alligator sinensis) in eastern China using molecular methods. The results of microscopic examination showed that no intestinal parasites were detected among the 491 fecal samples examined from the Chinese alligators. The overall prevalence for Cryptosporidium was 0.41% (2/491) by PCR detection using the SSU rRNA locus. Sequence and phylogenetic analysis of the SSU rRNA, COWP, and actin genes revealed the presence of Cryptosporidium testudinis, which has been isolated primarily from chelonians. This is the first detection of the specific DNA of C. testudinis in the feces of the Chinese alligator. This study expands our knowledge of the Cryptosporidium species involved in crocodiles, and more extensive studies are necessary to confirm the validity of C. testudinis in crocodiles.


Assuntos
Jacarés e Crocodilos/parasitologia , Criptosporidiose/parasitologia , Cryptosporidium/isolamento & purificação , Animais , China/epidemiologia , Criptosporidiose/epidemiologia , Cryptosporidium/classificação , Cryptosporidium/genética , DNA de Protozoário/genética , DNA Ribossômico/genética , Fezes/parasitologia , Genes de Protozoários/genética , Filogenia
20.
J Chem Phys ; 150(9): 094302, 2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30849870

RESUMO

The generalized oscillator strengths of the low-lying valence-shell excitations of N2, O2, and C2H2 have been studied by the high-energy electron scattering, the high-resolution inelastic X-ray scattering, and the multireference single- and double-excitation configuration-interaction methods. Good agreement between the present electron-scattering results and the X-ray-scattering ones for the a''1Σg +v'=0 and a''1Σg +v'=1+b1Πuv'=0 excitations of N2 and the A'3Δu excitation of O2 is achieved in the small squared momentum transfer region, while obvious discrepancies among them are observed in the large squared momentum transfer region. This phenomenon indicates that the first Born approximation is satisfied in the small squared momentum transfer region, while it does not hold in the large squared momentum transfer region at an incident electron energy of 1500 eV, in view of the fact that the first Born approximation is satisfied in the X-ray scattering. In addition, the present calculation for the a''1Σg + excitation shows that the traditional assigned v' = 0 and 1 of the a″1Σg + excitation correspond to v' = 9 and 13 of the 21Σg + excitation and reproduces the X-ray-scattering results of the a''1Σg +v'=0 excitation very well except the ones in the small squared momentum transfer region. We also report the generalized oscillator strengths of the à + B̃ excitations of C2H2, and its profile shows that the bending geometry has great influence on the transition feature.

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