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1.
Proc Natl Acad Sci U S A ; 119(40): e2200835119, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-36161936

RESUMO

Ice cores from alpine glaciers are unique archives of past global and regional climate conditions. However, recovering climate records from these ice cores is often hindered by the lack of a reliable chronology, especially in the age range of 100 to 500 anni (a) for which radiometric dating has not been available so far. We report on radiometric 39Ar dating of an ice core from the Tibetan Plateau and the construction of a chronology covering the past 1,300 a using the obtained 39Ar ages. This is made possible by advances in the analysis of 39Ar using the laser-based detection method atom trap trace analysis, resulting in a twofold increase in the upper age limit of 39Ar dating. By measuring the anthropogenic 85Kr along with 39Ar we quantify and correct modern air contamination, thus removing a major systematic uncertainty of 39Ar dating. Moreover, the 85Kr data for the top part of the ice core provide information on firn processes, including the age difference between the ice and its enclosed gas. This first application of 39Ar and 85Kr to an ice core facilitates further ice cores from nonpolar glaciers to be used for recovering climate records of the Common Era, a period including pronounced anomalies such as the Little Ice Age and the Medieval Warm Period.


Assuntos
Camada de Gelo , Datação Radiométrica , Clima , Mudança Climática , Datação Radiométrica/métodos , Tibet
2.
Plant Physiol ; 192(2): 945-966, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-36718522

RESUMO

Verticillium wilt caused by Verticillium dahliae is a serious vascular disease in cotton (Gossypium spp.). V. dahliae induces the expression of the CAROTENOID CLEAVAGE DIOXYGENASE 7 (GauCCD7) gene involved in strigolactone (SL) biosynthesis in Gossypium australe, suggesting a role for SLs in Verticillium wilt resistance. We found that the SL analog rac-GR24 enhanced while the SL biosynthesis inhibitor TIS108 decreased cotton resistance to Verticillium wilt. Knock-down of GbCCD7 and GbCCD8b genes in island cotton (Gossypium barbadense) decreased resistance, whereas overexpression of GbCCD8b in upland cotton (Gossypium hirsutum) increased resistance to Verticillium wilt. Additionally, Arabidopsis (Arabidopsis thaliana) SL mutants defective in CCD7 and CCD8 putative orthologs were susceptible, whereas both Arabidopsis GbCCD7- and GbCCD8b-overexpressing plants were more resistant to Verticillium wilt than wild-type (WT) plants. Transcriptome analyses showed that several genes related to the jasmonic acid (JA)- and abscisic acid (ABA)-signaling pathways, such as MYELOCYTOMATOSIS 2 (GbMYC2) and ABA-INSENSITIVE 5, respectively, were upregulated in the roots of WT cotton plants in responses to rac-GR24 and V. dahliae infection but downregulated in the roots of both GbCCD7- and GbCCD8b-silenced cotton plants. Furthermore, GbMYC2 suppressed the expression of GbCCD7 and GbCCD8b by binding to their promoters, which might regulate the homeostasis of SLs in cotton through a negative feedback loop. We also found that GbCCD7- and GbCCD8b-silenced cotton plants were impaired in V. dahliae-induced reactive oxygen species (ROS) accumulation. Taken together, our results suggest that SLs positively regulate cotton resistance to Verticillium wilt through crosstalk with the JA- and ABA-signaling pathways and by inducing ROS accumulation.


Assuntos
Arabidopsis , Verticillium , Gossypium/genética , Gossypium/metabolismo , Verticillium/fisiologia , Arabidopsis/genética , Arabidopsis/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Hormônios/metabolismo , Resistência à Doença/genética , Doenças das Plantas/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
3.
Syst Biol ; 72(2): 319-340, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-36130311

RESUMO

What happens when organisms actively modify their environment? Clarifying the role of construction behavior on a macroevolutionary scale is crucial to interpreting phenotypic evolution. Spiders, an extremely successful group of animals exhibiting a wide variety of functional, morphological, and behavioral diversity, are ideal candidates to test whether animal behaviors are related to their phenotypic evolution. Herein, we reconstructed the phylogenomic relationships of 303 spiders covering 105 families with 99 newly developed molecular markers that universally apply across Araneae, and explicitly tested the potential link between construction behavior and somatic evolution based on extensive morphological data from 3,342 extant species and 682 fossil species. Our dated molecular phylogeny provides the backbone for analyses, revealing the behavioral and ecological processes behind these spiders' morphological adaptations. Evolutionary model analyses showed the artifacts constructed by spiders, especially the suspending webs, expand the spider's ability to inhabit different habitats. These artifacts have more substantial impacts on their somatic traits than habitats and promote different trajectories of morphological evolution. Specifically, for spiders, silk-lined burrowing produced larger bodies, relatively shorter legs, and longer patellae, while web-building produced smaller bodies, relatively longer legs, and shorter patellae, and hunting promoted an intermediate morphological size. Molecular convergence analysis showed that genes related to morphogenesis or response to stimulus and stress are enriched in spiders with construction behavior. Our study demonstrated that the construction behavior of an animal plays a crucial role in determining the direction and intensity of the selection pressure imposed on it and provides strong evidence that construction behaviors are associated with phenotypic evolution on macroevolutionary timescales. [Araneae; body size; habitat change; molecular marker; leg length; phylogenomics.].


Assuntos
Evolução Biológica , Aranhas , Animais , Filogenia , Seda/genética , Ecossistema
4.
J Org Chem ; 89(3): 1719-1726, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38204281

RESUMO

As an interim paradigm for the catalysts between those based on more conventional mononuclear molecular Pd complexes and Pdn nanoparticles widely used in organic synthesis, polynuclear palladium clusters have attracted great attention for their unique reactivity and electronic properties. However, the development of Pd cluster catalysts for organic transformations and mechanistic investigations is still largely unexploited. Herein, we disclose the use of trinuclear palladium (Pd3Cl) species as an active catalyst for the direct C-H α-arylation of benzo[b]furans with aryl iodides to afford 2-arylbenzofurans in good yields under mild conditions. With this method, broad substrate adaptability was observed, and several drug intermediates were synthesized in high yields. Mechanistic studies indicated that the Pd3 core most likely remained intact throughout the reaction course.

5.
Syst Biol ; 69(5): 987-998, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32011715

RESUMO

Biological migrations between India and Southeast (SE) Asia provide an ideal system for exploring the effects of geology and climate on species ranges. Geologists have confirmed that the direct collision between India and Eurasia occurred in the Early Eocene, but most migrations occurred between the Indian subcontinent and SE Asia rather than the former and the southern margin of Eurasia. To explain this seemingly paradoxical disconnect between the routes of plate movement and biological migration, we studied the evolutionary history of the tropical spider family Ochyroceratidae based on 101 globally distributed species. We infer a robust dated phylogeny using both transcriptomic data and a data set of classical markers and relate these to biogeographic and climatic analyses. Our results indicate that the monophyly of Ochyroceratidae is strongly supported, and the divergence times suggest a Cretaceous Gondwanan origin of the family. Reconstructed biogeographic histories support a dispersal event from the Indian subcontinent to islands of SE Asia 55-38 Ma. Climatic analyses and the fossil record reveal that ochyroceratids are characterized by a high degree of tropical niche conservatism, and that the ancestor of the Indian and SE Asian clades originated in very warm, wet environments. Early Eocene tropical, perhumid climates in India, and SE Asia may have facilitated ochyroceratid migration, whereas the dry or seasonal climate extending from the eastern coast of China to Central Asia may have acted as a barrier, preventing dispersal. Our analyses suggest that climate plays a more important role than geology in biological migration from the Indian subcontinent to SE Asia, providing new insights into the Indian-Asian biogeographic link. [Biogeography; ecology; geological connections; macroevolution; paleoclimate.].


Assuntos
Migração Animal , Evolução Biológica , Ecossistema , Aranhas/classificação , Animais , Sudeste Asiático , Aranhas/fisiologia , Clima Tropical
6.
Mar Drugs ; 19(4)2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33808126

RESUMO

Hepatitis B virus (HBV) infection remains a major global health problem. It is therefore imperative to develop drugs for anti-hepatitis B with high-efficiency and low toxicity. Attracted by the observations and evidence that the symptoms of some patients from the Southern Fujian, China, suffering from hepatitis B were alleviated after daily eating an edible marine mollusk, Thais clavigera (Küster 1860) (TCK). Water-soluble polysaccharide from TCK (TCKP1) was isolated and characterized. The anti-HBV activity of TCKP1 and its regulatory pathway were investigated on both HepG2.2.15 cell line and HBV transgenic mice. The data obtained from in vitro studies showed that TCKP1 significantly enhanced the production of IFN-α, and reduced the level of HBV antigens and HBV DNA in the supernatants of HepG2.2.15 cells in a dose-dependent manner with low cytotoxicity. The result of the study on the HBV transgenic mice further revealed that TCKP1 significantly decreased the level of transaminases, HBsAg, HBeAg, and HBV DNA in the serum, as well as HBsAg, HBeAg, HBV DNA, and HBV RNA in the liver of HBV transgenic (HBV-Tg) mice. Furthermore, TCKP1 exhibited equivalent inhibitory effect with the positive control tenofovir alafenamide (TAF) on the markers above except for HBV DNA even in low dosage in a mouse model. However, the TCKP1 high-dose group displayed stronger inhibition of transaminases and liver HBsAg, HBeAg, and HBV RNA when compared with those of TAF. Meanwhile, inflammation of the liver was, by pathological observation, relieved in a dose-dependent manner after being treated with TCKP1. In addition, elevated levels of interleukin-12 (IL-12) and interferon γ (IFN-γ), and reduced level of interleukin-4 (IL-4) in the serum were observed, indicating that the anti-HBV effect of TCKP1 was achieved by potentiating immunocyte function and regulating the balance of Th1/Th2 cytokines.


Assuntos
Antivirais/farmacologia , Vírus da Hepatite B/efeitos dos fármacos , Hepatite B/tratamento farmacológico , Moluscos/metabolismo , Polissacarídeos/farmacologia , Animais , Antivirais/isolamento & purificação , Citocinas/metabolismo , Modelos Animais de Doenças , Células Hep G2 , Hepatite B/imunologia , Hepatite B/metabolismo , Hepatite B/virologia , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Interações Hospedeiro-Patógeno , Humanos , Mediadores da Inflamação/metabolismo , Camundongos Transgênicos , Polissacarídeos/isolamento & purificação , Equilíbrio Th1-Th2/efeitos dos fármacos , Carga Viral
7.
Anal Bioanal Chem ; 411(15): 3353-3360, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30957206

RESUMO

Lamotrigine is one of the most widely used antiepileptic drugs in the treatment of epilepsy. This kind of drug needs to be used in the long term and should be quantitatively detected in the blood of patients to avoid drug toxicity caused by individual differences and environmental and pathological changes in the process of taking. The detection of antiepileptic drugs in human blood is challenging because of their low contents and the interference of complex matrices. Thus, the sample enrichment method has been commonly used to improve the sensitivity of detection. In this work, we have synthesized a new "bi-(4-vinyl phenylquinoline) amide" compound and used it as the monomer to produce the hyper-cross-linked microporous polymer for the enrichment of lamotrigine. This material has a high adsorption capacity, specificity, and linearity, which can improve the detection sensitivity of lamotrigine by high-performance liquid chromatography (HPLC). The mechanism of this phenomenon has also been investigated. Finally, we have developed the microporous polymer enrichment coupled with HPLC method for the quantitative determination of lamotrigine in rat and human serum samples. This method has excellent precision, accuracy, and recovery, meeting the test of biological sample. The low limit of quantitation was 0.625 µg/mL. Graphical abstract.


Assuntos
Anticonvulsivantes/sangue , Monitoramento de Medicamentos/métodos , Lamotrigina/sangue , Polivinil/química , Quinolinas/química , Microextração em Fase Sólida/métodos , Adsorção , Amidas/química , Animais , Anticonvulsivantes/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Lamotrigina/isolamento & purificação , Limite de Detecção , Masculino , Porosidade , Ratos , Ratos Sprague-Dawley
8.
Dermatology ; 235(5): 426-433, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31256167

RESUMO

BACKGROUND: Postherpetic neuralgia is the most common complication of herpes zoster, affecting 30% of patients. It seriously affects the quality of life of patients and the curative effect of treatment is limited. So far, researchers do not fully understand the risk factors for postherpetic neuralgia and more research is needed. OBJECTIVE: The aim of this paper was to investigate the risk factors for postherpetic neuralgia and provide reference for clinical diagnosis and treatment. METHODS: A total of 202 inpatients with herpes zoster in the General Hospital of Tianjin Medical University were recruited as study subjects. According to the occurrence of postherpetic neuralgia, the patients were divided into the postherpetic neuralgia group and the nonpostherpetic neuralgia group. Data on age, gender, initial symptoms, clinical classification, involved nerves, pain grading, antiviral therapy, glucocorticoid use, and other clinical data of patients in the two groups were collected and statistically analyzed. Univariate and multivariate analysis methods were used to analyze the differences between the two groups and determine the influencing factors of postherpetic neuralgia. RESULTS: The univariate statistical analysis of the factors influencing postherpetic neuralgia showed that the contribution of gender, initial symptoms, general clinical classification, use of glucocorticoid, and the interval from onset to antiviral therapy were not statistically significant, while the differences in age, specific clinical classification, involved nerves, severity of pain during the acute stage, and body side of skin lesion distribution were statistically significant. Multivariate logistic regression analysis showed that gender, use of glucocorticoid, interval from onset to antiviral therapy, involved nerves, and specific clinical classification showed no statistical significance. However, there were significant differences in age, body side of skin lesion distribution, general clinical classification, and degree of pain during the acute stage of the disease. CONCLUSION: Pain during the acute stage of herpes zoster, age greater than 70 years, and serious type of skin lesion are risk factors for postherpetic neuralgia (p < 0.05, OR >1).


Assuntos
Herpes Zoster/complicações , Neuralgia Pós-Herpética/diagnóstico , Neuralgia Pós-Herpética/terapia , Dermatopatias Virais/virologia , Doença Aguda , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Herpes Zoster/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Neuralgia Pós-Herpética/etiologia , Dor/etiologia , Fatores de Risco
9.
Infect Immun ; 86(1)2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29038127

RESUMO

The cryptic plasmid is essential for Chlamydia muridarum dissemination from the genital tract to the gastrointestinal (GI) tract. Following intravaginal inoculation, a C. muridarum strain deficient in plasmid-encoded pGP3 or pGP4 but not pGP5, pGP7, or pGP8 failed to spread to the mouse gastrointestinal tract, although mice infected with these strains developed productive genital tract infections. pGP3- or pGP4-deficient strains also failed to colonize the gastrointestinal tract when delivered intragastrically. pGP4 regulates pGP3, while pGP3 does not affect pGP4 expression, indicating that pGP3 is critical for C. muridarum colonization of the gastrointestinal tract. Mutants deficient in GlgA, a chromosome-encoded protein regulated by pGP4, also consistently colonized the mouse gastrointestinal tract. Interestingly, C. muridarum colonization of the gastrointestinal tract positively correlated with pathogenicity in the upper genital tract. pGP3-deficient C. muridarum strains did not induce hydrosalpinx or spread to the GI tract even when delivered to the oviduct by intrabursal inoculation. Thus, the current study not only has revealed that pGP3 is a novel chlamydial colonization factor in the gastrointestinal tract but also has laid a foundation for investigating the significance of gastrointestinal Chlamydia.


Assuntos
Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Infecções por Chlamydia/microbiologia , Chlamydia muridarum/genética , Chlamydia muridarum/patogenicidade , Trato Gastrointestinal/microbiologia , Infecções do Sistema Genital/microbiologia , Fatores de Virulência/genética , Animais , Linhagem Celular Tumoral , Feminino , Genitália/microbiologia , Células HeLa , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Oviductos/microbiologia , Plasmídeos/genética
10.
Mol Phylogenet Evol ; 127: 146-155, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29803949

RESUMO

The Cretaceous experienced one of the most remarkable greenhouse periods in geological history. During this time, ecosystem reorganization significantly impacted the diversification of many groups of organisms. The rise of angiosperms marked a major biome turnover. Notwithstanding, relatively little remains known about how the Cretaceous global ecosystem impacted the evolution of spiders, which constitute one of the most abundant groups of predators. Herein, we evaluate the transcriptomes of 91 taxa representing more than half of the spider families. We add 23 newly sequenced taxa to the existing database to obtain a robust phylogenomic assessment. Phylogenetic reconstructions using different datasets and methods obtain novel placements of some groups, especially in the Synspermiata and the group having a retrolateral tibial apophysis (RTA). Molecular analyses indicate an expansion of the RTA clade at the Early Cretaceous with a hunting predatory strategy shift. Fossil analyses show a 7-fold increase of diversification rate at the same period, but this likely owes to the first occurrence of spiders in amber deposit. Additional analyses of fossil abundance show an accumulation of spider lineages in the Early Cretaceous. We speculate that the establishment of a warm greenhouse climate pumped the diversification of spiders, in particular among webless forms tracking the abundance of insect prey. Our study offers a new pathway for future investigations of spider phylogeny and diversification.


Assuntos
Efeito Estufa , Filogenia , Aranhas/classificação , Animais , Biodiversidade , Bases de Dados Genéticas , Fósseis , Genômica , Funções Verossimilhança , Aranhas/genética , Fatores de Tempo
11.
Can J Microbiol ; 64(6): 376-384, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29510061

RESUMO

Chlamydia trachomatis is the most common cause of bacterial sexually transmitted infections. The effect of antibiotic treatment is not satisfactory, and there is currently no vaccine to prevent C. trachomatis infection. Our results showed that Chlamydia virus CPG1 capsid protein Vp1 treatment significantly inhibited C. trachomatis growth in cell culture, and the inclusion numbers of different C. trachomatis serotypes were decreased. In addition, we conducted a preliminary investigation of the possible mechanisms behind the Vp1 inhibition effects and the C. trachomatis molecules targeted by Vp1. Using far-western blot and GST pull-down assay, we found that purified Vp1 can bind to the C. trachomatis outer membrane protein PmpI. PmpI polyclonal antibody treatment markedly reduced the inhibitory effect of Vp1 on C. trachomatis infectivity. On the basis of these experimental results, we infer that PmpI participates in the inhibitory effect of Vp1 and may be a potential receptor of Vp1 in the outer membrane of C. trachomatis. Our research provides clues regarding the molecular mechanisms underlying the interactions between chlamydia virus and chlamydia.


Assuntos
Anticorpos Antibacterianos/farmacologia , Proteínas da Membrana Bacteriana Externa/fisiologia , Chlamydia trachomatis/efeitos dos fármacos , Proteínas Estruturais Virais/farmacologia , Chlamydia trachomatis/patogenicidade , Feminino , Células HeLa , Humanos
12.
J BUON ; 23(5): 1552-1557, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30570885

RESUMO

PURPOSE: To analyze the effects of Oxycontin on ß-endorphin (ß-EP), calcitonin gene-related peptide (CGRP) and prostaglandin E2 (PGE2) in treating patients with cancer pain, and to investigate and discuss the role and value of Oxycontin in treating cancer pain. METHODS: A total of 95 patients (60 male and 35 female) were enrolled in the study, who were diagnosed in our hospital with malignant tumors complicated with pain from May 2016 to July 2017. All received Oxycontin for pain relief in addition to conventional treatment. The role of Oxycontin was analyzed by collecting the patients' general information, age, gender, Karnofsky performance status (KPS) score, site of pain and degree of pain, and by detecting the remission rates of clinical symptoms, average analgesic time, number of pain outbreak per day, levels of ß-EP, CGRP and PGE2, as well as changes of KPS score, Zubrod performance status (ZPS) score and quality of life (QoL) score of the enrolled patients before treatment and at 1 week afer treatment. RESULTS: (1) Afer treatment with Oxycontin, the remission rate of clinical symptoms was signifcantly increased, the average analgesic time was extended remarkably and the number of pain outbreaks per day was decreased notably. All the differences were statistically signifcant (p<0.05). (2) For patients with cancer pain receiving Oxycontin, the main adverse reactions were nausea and vomiting (15.37%), followed by constipation, abdominal distension and anorexia. (3) At 1 week afer Oxycontin therapy, the KPS score and QoL score of the enrolled patients were increased, while the ZPS score was decreased, and the differences were statistically signifcant (p<0.05). (4) At 1 week afer treatment with Oxycontin, the levels of ß-EP, CGRP and PGE2 of the enrolled patients were signifcantly lowered (p<0.05). (5) The levels of ß-EP, CGRP and PGE2 with regard to the average analgesic time were negatively correlated with ß-EP (r=-0.765, p<0.01), CGRP (r=-0.673, p<0.01) and PGE2 (r=-0.801, p<0.01). CONCLUSIONS: On treating patients with cancer pain, Oxycontin can signifcantly decrease the ß-EP, CGRP and PGE2 levels, ameliorate the clinical symptoms, effectively relieve the pain and improve the QoL to some extent.


Assuntos
Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Dor do Câncer/tratamento farmacológico , Dinoprostona/metabolismo , Oxicodona/uso terapêutico , beta-Endorfina/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Infect Immun ; 85(8)2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28584162

RESUMO

Chlamydiae colonize the gastrointestinal tracts of both animals and humans. However, their medical significance remains unknown. We have previously shown that wild-type Chlamydia muridarum spreads to and establishes stable colonization of the gastrointestinal tract following intravaginal inoculation. In the present study, we found that C. muridarum with mutations in chromosomal genes tc0237 and/or tc0668 was defective in spreading to the mouse gastrointestinal tract, which correlated with its attenuated pathogenicity in the upper genital tract. This correlation was more consistent than that of chlamydial pathogenicity with ascending infection in the genital tract, since attenuated C. muridarum spread significantly less to the gastrointestinal tract but maintained robust ascending infection of the upper genital tract. Transcervical inoculation further confirmed the correlation between C. muridarum spreading to the gastrointestinal tract and its pathogenicity in the upper genital tract. Finally, defective spreading of C. muridarum mutants was due to their inability to colonize the gastrointestinal tract since intragastric inoculation did not rescue the mutants' colonization. Thus, promoting C. muridarum colonization of the gastrointestinal tract may represent a primary function of the TC0237 and TC0668 proteins. Correlation of chlamydial colonization of the gastrointestinal tract with chlamydial pathogenicity in the upper genital tract suggests a potential role for gastrointestinal chlamydiae in genital tract pathogenicity.


Assuntos
Infecções por Chlamydia/microbiologia , Chlamydia muridarum/genética , Chlamydia muridarum/patogenicidade , Cromossomos Bacterianos/genética , Trato Gastrointestinal/microbiologia , Mutação , Animais , Chlamydia muridarum/crescimento & desenvolvimento , Chlamydia muridarum/fisiologia , Modelos Animais de Doenças , Feminino , Camundongos , Infecções do Sistema Genital/microbiologia , Vagina/microbiologia
14.
Infect Immun ; 84(9): 2697-702, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27382018

RESUMO

Despite the extensive in vitro characterization of CPAF (chlamydial protease/proteasome-like activity factor), its role in chlamydial infection and pathogenesis remains unclear. We now report that a Chlamydia trachomatis strain deficient in expression of CPAF (L2-17) is no longer able to establish a successful infection in the mouse lower genital tract following an intravaginal inoculation. The L2-17 organisms were cleared from the mouse lower genital tract within a few days, while a CPAF-sufficient C. trachomatis strain (L2-5) survived in the lower genital tract for more than 3 weeks. However, both the L2-17 and L2-5 organisms maintained robust infection courses that lasted up to 4 weeks when they were directly delivered into the mouse upper genital tract. The CPAF-dependent chlamydial survival in the lower genital tract was confirmed in multiple strains of mice. Thus, we have demonstrated a critical role of CPAF in promoting C. trachomatis survival in the mouse lower genital tracts. It will be interesting to further investigate the mechanisms of the CPAF-dependent chlamydial pathogenicity.


Assuntos
Infecções por Chlamydia/microbiologia , Chlamydia trachomatis/metabolismo , Endopeptidases/metabolismo , Genitália/microbiologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Animais , Linhagem Celular Tumoral , Feminino , Células HeLa , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL
15.
Infect Immun ; 84(8): 2382-2388, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27271744

RESUMO

Chlamydia has been detected in the gastrointestinal tracts of both animals and humans. However, it remains unclear whether the chlamydial organisms can be introduced into the gastrointestinal tract via pathways independent of the oral and anal routes. We have recently shown that Chlamydia muridarum spreads from the genital tract to the gastrointestinal tract potentially via the circulatory system. To test whether hematogenous C. muridarum can spread to and establish a long-lasting colonization in the mouse gastrointestinal tract, we inoculated mice intravenously with a luciferase-expressing C. muridarum strain and monitored its distribution. After tail vein inoculation, most luciferase-generated bioluminescence signals were detected in the mouse abdominal area throughout the experiment. The ex vivo imaging revealed that the abdominal signals came from the gastrointestinal tract tissues. Simultaneous monitoring of chlamydial organisms in individual organs or tissues revealed an initial stage of systemic spreading followed by a long-lasting infection in the gastrointestinal tract. A retro-orbital vein inoculation of the C. muridarum organisms at a lower dose in a different mouse strain also led to colonization of the gastrointestinal tract. We have demonstrated that intravenous C. muridarum inoculation can result in colonization of the gastrointestinal tract, suggesting that the chlamydial organisms may use the sexual behavior-independent circulation pathway to infect the gastrointestinal tract.


Assuntos
Infecções por Chlamydia/microbiologia , Chlamydia muridarum/fisiologia , Gastroenterite/microbiologia , Animais , Bacteriemia , Carga Bacteriana , Linhagem Celular , Infecções por Chlamydia/diagnóstico , Modelos Animais de Doenças , Feminino , Gastroenterite/diagnóstico , Humanos , Camundongos , Infecções do Sistema Genital/microbiologia
16.
J Clin Lab Anal ; 30(5): 697-701, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26987564

RESUMO

BACKGROUND: Chlamydia trachomatis causes the most common bacterial sexually transmitted infection (STI) worldwide. Although highly sensitive nucleic acid amplification tests (NAATs) are used to routinely diagnose chlamydial infection, C. trachomatis isolation by cell culture is still preferred for legal cases and epidemiological studies because of its high specificity; however, the sensitivity of traditional two-passage diagnostic cultures is significantly lower than that of NAATs. Therefore, we sought to analyze if additional in vitro passaging of clinical samples would improve detection sensitivity of C. trachomatis. METHODS: Clinical swabs (n = 428) were collected from Tianjin Medical University General Hospital, grown in McCoy cells for up to five passages, and analyzed for the presence of inclusions by iodine staining. Results were confirmed by routine PCR-based methods. RESULTS: Viable C. trachomatis organisms were detected in 91 (21.26%) swabs with the traditional two-passage protocol, which increased to 145 (33.88%) and 149 (34.81%) following three and four passages, respectively. Thus, the standard protocol yielded a false-negative rate of nearly 39%. Subsequent PCR-based diagnostics revealed a concordance rate of 80.98% between these two methods without any false negatives. CONCLUSION: The results of this study support the use of a three-passage Chlamydia culture procedure to increase the detection sensitivity of this method.


Assuntos
Técnicas de Cultura de Células/métodos , Técnicas de Cultura de Células/normas , Chlamydia trachomatis/crescimento & desenvolvimento , Adulto , Idoso , Eletroforese em Gel de Ágar , Humanos , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Padrões de Referência , Sensibilidade e Especificidade , Coloração e Rotulagem , Adulto Jovem
17.
Phytochemistry ; 225: 114192, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38901624

RESUMO

Meliasanines A-L, twelve previously unreported tirucallane-type triterpenoids, together with fifteen known ones, have been isolated from the stem bark of Melia toosendan. Their structures and absolute configurations were determined based on HRESIMS, and NMR, combined with calculated ECD and single-crystal X-ray diffraction analyses. Subsequently, all compounds except 10 were evaluated for their inhibitory effect on the production of nitric oxide induced by lipopolysaccharide in RAW264.7 macrophage cells. The results indicated that seven compounds (1, 13, 14, 16, 20, 22, and 23) exhibited significant NO inhibitory effects, with IC50 values ranging from 1.35 to 5.93 µM, which were more effective than the positive control indomethacin (IC50 = 13.18 µM). Moreover, the corresponding results of Western blot analysis revealed that meliasanine A (1) can significantly suppress the protein expression of inducible nitric oxide synthase and cyclooxygenase 2 in a concentration-dependent manner. The mechanism study suggested that meliasanine A exerts an anti-inflammatory effect via the nuclear factor-κB signaling pathway by suppressing phosphorylation of P65 and IκBα.


Assuntos
Anti-Inflamatórios , Lipopolissacarídeos , Melia , NF-kappa B , Óxido Nítrico , Transdução de Sinais , Triterpenos , Camundongos , Animais , Triterpenos/farmacologia , Triterpenos/química , Triterpenos/isolamento & purificação , NF-kappa B/metabolismo , NF-kappa B/antagonistas & inibidores , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Óxido Nítrico/biossíntese , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/metabolismo , Estrutura Molecular , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/antagonistas & inibidores , Melia/química , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Casca de Planta/química , Ciclo-Oxigenase 2/metabolismo , Relação Dose-Resposta a Droga , Relação Estrutura-Atividade
18.
Mol Plant Pathol ; 25(6): e13483, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38829344

RESUMO

As a universal second messenger, cytosolic calcium (Ca2+) functions in multifaceted intracellular processes, including growth, development and responses to biotic/abiotic stresses in plant. The plant-specific Ca2+ sensors, calmodulin and calmodulin-like (CML) proteins, function as members of the second-messenger system to transfer Ca2+ signal into downstream responses. However, the functions of CMLs in the responses of cotton (Gossypium spp.) after Verticillium dahliae infection, which causes the serious vascular disease Verticillium wilt, remain elusive. Here, we discovered that the expression level of GbCML45 was promoted after V. dahliae infection in roots of cotton, suggesting its potential role in Verticillium wilt resistance. We found that knockdown of GbCML45 in cotton plants decreased resistance while overexpression of GbCML45 in Arabidopsis thaliana plants enhanced resistance to V. dahliae infection. Furthermore, there was physiological interaction between GbCML45 and its close homologue GbCML50 by using yeast two-hybrid and bimolecular fluorescence assays, and both proteins enhanced cotton resistance to V. dahliae infection in a Ca2+-dependent way in a knockdown study. Detailed investigations indicated that several defence-related pathways, including salicylic acid, ethylene, reactive oxygen species and nitric oxide signalling pathways, as well as accumulations of lignin and callose, are responsible for GbCML45- and GbCML50-modulated V. dahliae resistance in cotton. These results collectively indicated that GbCML45 and GbCML50 act as positive regulators to improve cotton Verticillium wilt resistance, providing potential targets for exploitation of improved Verticillium wilt-tolerant cotton cultivars by genetic engineering and molecular breeding.


Assuntos
Cálcio , Resistência à Doença , Gossypium , Doenças das Plantas , Proteínas de Plantas , Gossypium/microbiologia , Gossypium/genética , Gossypium/metabolismo , Gossypium/imunologia , Resistência à Doença/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Cálcio/metabolismo , Regulação da Expressão Gênica de Plantas , Calmodulina/metabolismo , Calmodulina/genética , Arabidopsis/microbiologia , Arabidopsis/genética , Arabidopsis/imunologia , Arabidopsis/metabolismo , Ascomicetos/fisiologia , Ascomicetos/patogenicidade , Plantas Geneticamente Modificadas , Verticillium/fisiologia , Verticillium/patogenicidade
19.
Diagnostics (Basel) ; 13(4)2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36832111

RESUMO

Purpose: As the number of patients with chronic obstructive pulmonary disease continues to increase, it is increasingly important to understand the impact of cardiovascular risk on the progression of chronic obstructive pulmonary disease, which can provide guidance for clinical medication and recommendations for patient care and rehabilitation. The purpose of this study was to investigate the relationship between cardiovascular risk and the progression of chronic obstructive pulmonary disease (COPD). Methods: Selected COPD patients admitted to hospital from June 2018 to July 2020 were included in the study for prospective analysis, and patients who showed more than two instances of moderate deterioration or severe deterioration within one year before the consultation were defined as COPD patients, and all participants underwent relevant tests and assessments. Results: Multivariate correction analysis showed that a worsening phenotype improved the risk of carotid artery intima-media thickness exceeding 75% by nearly three times, and it had no relation with the degree of COPD severity and global cardiovascular risk; in addition, the relationship between a worsening phenotype and high carotid intima-media thickness (c-IMT) was more pronounced in patients under 65 years of age. Conclusions: The existence of subclinical atherosclerosis is individually related to the worsening phenotype, and the difference is more obvious in young patients. Therefore, the control of vascular risk factors in these patients should be strengthened.

20.
Sci Total Environ ; 856(Pt 2): 159214, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36208735

RESUMO

Dust and black carbon (BC) can darken snow and ice surface and play pivotal roles in glacier mass loss. Thus, a quantitative assessment of their contributions to glacier summer melting is critical. During the summer of 2018, surface snow and ice were sampled, and the albedo and mass balance were continuously measured in the ablation zone of Laohugou Glacier No. 12 in the western Qilian Mountains. The physical properties of dust and BC were measured in the laboratory, and their impacts on glacier surface albedo reduction and melting were simulated. The results indicate that the ice surface in the ablation zone was enriched with substantial amounts of particles, and the average particle concentrations of these samples were hundreds of times higher than those of fresh snow. The BC mass absorption cross-sections (MACs) ranged from 3.1 m2 g-1 at 550 nm for dirty ice to 4.6 m2 g-1 for fresh snow, largely owing to meltwater percolation and particle collapse. The spectral variations in dust MACs were significantly different in the visible light bands and near-infrared bands from those in the other areas. Moreover, the two-layer surface energy and mass balance model with the new albedo parameterization formula was validated and agreed well with the experimental measurements of spectral albedo, broadband albedo, and mass balance. BC and dust combined resulted in 26.7 % and 54.4 % of the total mass loss on the cleaner and dirtier (particle enriched) surfaces in the ablation zone, respectively, compared to particle-free surfaces, and although both impurities played vital roles, dust was the more prominent factor in accelerating glacier melting on the northeastern Tibetan Plateau. This study emphasizes the importance of dust in cryosphere changes where Tibetan glaciers are strongly affected by Asian dust deposition.


Assuntos
Poeira , Camada de Gelo , Poeira/análise , Tibet , Monitoramento Ambiental/métodos , Neve , Fuligem/análise
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