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1.
Front Cell Infect Microbiol ; 14: 1334351, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38567020

RESUMO

Most tick-borne viruses (TBVs) are highly pathogenic and require high biosecurity, which severely limits their study. We found that Sindbis virus (SINV), predominantly transmitted by mosquitoes, can replicate in ticks and be subsequently transmitted, with the potential to serve as a model for studying tick-virus interactions. We found that both larval and nymphal stages of Rhipicephalus haemaphysaloides can be infected with SINV-wild-type (WT) when feeding on infected mice. SINV replicated in two species of ticks (R. haemaphysaloides and Hyalomma asiaticum) after infecting them by microinjection. Injection of ticks with SINV expressing enhanced Green Fluorescent Protein (eGFP) revealed that SINV-eGFP specifically aggregated in the tick midguts for replication. During blood-feeding, SINV-eGFP migrated from the midguts to the salivary glands and was transmitted to a new host. SINV infection caused changes in expression levels of tick genes related to immune responses, substance transport and metabolism, cell growth and death. SINV mainly induced autophagy during the early stage of infection; with increasing time of infection, the level of autophagy decreased, while the level of apoptosis increased. During the early stages of infection, the transcript levels of immune-related genes were significantly upregulated, and then decreased. In addition, SINV induced changes in the transcription levels of some functional genes that play important roles in the interactions between ticks and tick-borne pathogens. These results confirm that the SINV-based transmission model between ticks, viruses, and mammals can be widely used to unravel the interactions between ticks and viruses.


Assuntos
Carrapatos , Vírus , Animais , Camundongos , Sindbis virus/genética , Mosquitos Vetores , Mamíferos
2.
PeerJ ; 12: e17246, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38650653

RESUMO

Background: Obesity is a well-known predictor for poor postoperative outcomes of vascular surgery. However, the association between obesity and outcomes of thoracic endovascular aortic repair (TEVAR) is still unclear. This systematic review and meta-analysis was performed to assess the roles of obesity in the outcomes of TEVAR. Methods: We systematically searched the Web of Science and PubMed databases to obtain articles regarding obesity and TEVAR that were published before July 2023. The odds ratio (OR) or hazard ratio (HR) was used to assess the effect of obesity on TEVAR outcomes. Body mass index (BMI) was also compared between patients experiencing adverse events after TEVAR and those not experiencing adverse events. The Newcastle-Ottawa Scale was used to evaluate the quality of the enrolled studies. Results: A total of 7,849 patients from 10 studies were included. All enrolled studies were high-quality. Overall, the risk of overall mortality (OR = 1.49, 95% CI [1.02-2.17], p = 0.04) was increased in obese patients receiving TEVAR. However, the associations between obesity and overall complications (OR = 2.41, 95% CI [0.84-6.93], p = 0.10) and specific complications were all insignificant, including stroke (OR = 1.39, 95% CI [0.56-3.45], p = 0.48), spinal ischemia (OR = 0.97, 95% CI [0.64-1.47], p = 0.89), neurological complications (OR = 0.13, 95% CI [0.01-2.37], p = 0.17), endoleaks (OR = 1.02, 95% CI [0.46-2.29], p = 0.96), wound complications (OR = 0.91, 95% CI [0.28-2.96], p = 0.88), and renal failure (OR = 2.98, 95% CI [0.92-9.69], p = 0.07). In addition, the patients who suffered from postoperative overall complications (p < 0.001) and acute kidney injury (p = 0.006) were found to have a higher BMI. In conclusion, obesity is closely associated with higher risk of mortality after TEVAR. However, TEVAR may still be suitable for obese patients. Physicians should pay more attention to the perioperative management of obese patients.


Assuntos
Aorta Torácica , Procedimentos Endovasculares , Obesidade , Complicações Pós-Operatórias , Humanos , Obesidade/complicações , Obesidade/cirurgia , Procedimentos Endovasculares/efeitos adversos , Complicações Pós-Operatórias/mortalidade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Aorta Torácica/cirurgia , Índice de Massa Corporal , Fatores de Risco , Resultado do Tratamento , Correção Endovascular de Aneurisma
4.
Phytochemistry ; 217: 113912, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37918620

RESUMO

Artemisia argyi Levl. Et Vant, commonly known as "Chinese Mugwort," has been utilized in traditional Chinese medicine and cuisine for centuries. Aged Chinese Mugwort has been uncovered to possess superior quality and safety, and its ethyl acetate extract has been found to exhibit anti-hepatitis B virus (HBV) activity. In this study, twenty-five sesquiterpenoids were isolated and characterized from three-year-aged A. argyi. Among them, 14 previously undescribed sesquiterpenoids (1-14), featuring double bond oxidation or ring opening. It is hypothesized that during the aging process, sesquiterpenes undergo oxidative transformation of their double bonds to form alcohols due to external factors and inherent properties. The anti-HBV activity and cytotoxicity of all compounds were assessed in vitro using HepG 2.2.15 cells, and their structure-activity relationships were analyzed through three-dimensional quantitative structure-activity relationship (3D-QASR) techniques. The α-methylene-γ-lactone sesquiterpenoid derivatives were discovered to have potent inhibitory activity against HBV. This research may broaden the potential applications of Chinese Mugwort and offer further guidance for its development and utilization as functional food or traditional Chinese medicine.


Assuntos
Artemisia , Sesquiterpenos , Vírus da Hepatite B , Relação Quantitativa Estrutura-Atividade , Artemisia/química , Medicina Tradicional Chinesa , Sesquiterpenos/farmacologia
5.
Plants (Basel) ; 12(23)2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38068563

RESUMO

The allocation of plant biomass above and below ground reflects their strategic resource utilization, crucial for understanding terrestrial carbon flux dynamics. In our comprehensive study, we analyzed biomass distribution patterns in 580 broadleaved and 345 coniferous forests across China from 2005 to 2020, aiming to discern spatial patterns and key drivers of belowground biomass proportion (BGBP) in these ecosystems. Our research revealed a consistent trend: BGBP decreases from northwest to southeast in both forest types. Importantly, coniferous forests exhibited significantly higher BGBP compared to broadleaved forests (p < 0.001). While precipitation and soil nutrients primarily influenced biomass allocation in broadleaved forests, temperature and soil composition played a pivotal role in coniferous forests. Surprisingly, leaf traits had a negligible impact on BGBP (p > 0.05). Climatic factors, such as temperature and rainfall, influenced biomass partitioning in both strata by altering soil nutrients, particularly soil pH. These findings provide valuable insights into understanding carbon sequestration dynamics in forest ecosystems and improving predictions of the future trajectory of this critical carbon cycle component.

6.
Exp Appl Acarol ; 91(3): 497-507, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37870735

RESUMO

The repellent activity of Chinese cinnamon oil (Cinnamomum cassia) on nymphal ticks (Haemaphysalis longicornis Neumann, Rhipicephalus haemaphysaloides Supino, and Hyalomma asiaticum Schulze and Schlottke) was evaluated in a sample Y-tube bioassay. The results were based on the vertical migration of ticks during the host-seek phase and showed a dose-dependent repellent effect of Chinese cinnamon oil on the tested nymphs after 6 h. For H. longicornis, R. haemaphysaloides, and H. asiaticum at the concentrations (vol/vol) of 3, 3, and 1.5%, the repellent percentages over time were 68-97, 69-94, and 69-93%, respectively, which indicated strong repellent activities against ticks, similar to the positive control DEET (N,N-diethyl-3-methylbenzamide). Chinese cinnamon oil exerted the strongest effect on H. asiaticum nymphs. To our knowledge, this is the first study to investigate the repellent effects of Chinese cinnamon oil on ticks. Chinese cinnamon oil has considerable potential and should be developed as a practical tick repellent.


Assuntos
Cinnamomum aromaticum , Repelentes de Insetos , Ixodidae , Ninfa , Óleos Voláteis , Óleos de Plantas , Animais , Repelentes de Insetos/farmacologia , Ixodidae/efeitos dos fármacos , Ixodidae/crescimento & desenvolvimento , Ninfa/efeitos dos fármacos , Óleos Voláteis/farmacologia , Rhipicephalus/efeitos dos fármacos , Rhipicephalus/crescimento & desenvolvimento , China , Óleos de Plantas/farmacologia
7.
Materials (Basel) ; 16(9)2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37176242

RESUMO

Mold structure and cooling parameters are significant factors that affect the heat transfer capacity of high-speed continuous casting molds of billets. Therefore, a three-dimensional fluid flow and heat transfer model of a 160 mm × 160 mm billet mold was established, and its accuracy was verified. Thereby, the characteristics of heat transfer and influences of mold structure and cooling parameters on heat transfer in the high-speed continuous casting billet mold region were revealed. It was found that extending the effective length of a mold is the most valuable method to improve its heat transfer capability and achieve high-speed continuous casting. The total heat and the shell thickness at a mold outlet increased by 19% and 9.21% on average with every 100 mm extension. Enlarging the fillet radius could enhance the uniformity of heat transfer in the mold. Considering the loss of material, the optimal fillet radius of the mold was determined to be R = 10 mm.

8.
Sci Rep ; 13(1): 5724, 2023 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-37029182

RESUMO

Several studies have shown that males suffer more severe damage than females in the process of ischemia and reperfusion of the brain, heart and kidney. Accordingly, our study will reveal the correlation between the severity of hepatic ischemia‒reperfusion injury (HIRI) and sex, and preliminarily analyze the underlying mechanism. A total of 75 patients who were considered to have "benign liver tumors" at the initial admission and underwent partial hepatectomy were enrolled. We identified potential differences between different groups and discussed the correlation between the severity of HIRI and sex through a comparative analysis. Results showed that HIRI was more severe in males than in females, especially in younger patients. To explore whether estrogen level differences are the main reason for the sex differences in HIRI, we further revealed that HIRI in premenopausal females was more severe than that in postmenopausal females. By comparing the levels of gonadal hormones, we speculated that multiple gonadal hormones, including follicle-stimulating hormone, luteinizing hormone and testosterone, may jointly participate in the regulation of sex differences in HIRI together with estrogen.


Assuntos
Traumatismo por Reperfusão , Caracteres Sexuais , Humanos , Masculino , Feminino , Estudos Transversais , Fígado , Estrogênios , Hormônios Gonadais
9.
Parasit Vectors ; 16(1): 125, 2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37046327

RESUMO

BACKGROUND: Extracellular vesicles (EVs) are a heterogeneous group of cell-derived membranous structures that are important mediators of intercellular communication. Arthropods transport nutrients, signaling molecules, waste and immune factors to all areas of the body via the hemolymph. Little is known about tick hemolymph EVs. METHODS: Hemolymph was collected from partially fed Rhipicephalus haemaphysaloides and Hyalomma asiaticum ticks by making an incision with a sterile scalpel in the middle (between the femur and metatarsus) of the first pair of legs, which is known as leg amputation. EVs were isolated from hemolymph by differential centrifugation and characterized by transmission electron microscopy (TEM) and nanoparticle tracking analysis (NTA). Proteins extracted from the hemolymph EVs were analyzed by 4D label-free proteomics. The EVs were also examined by western blot and immuno-electron microscopy analysis. Intracellular incorporation of PHK26-labeled EVs was tested by adding labeled EVs to tick salivary glands and ovaries, followed by fluorescence microscopy. RESULTS: In this study, 149 and 273 proteins were identified by 4D label-free proteomics in R. haemaphysaloides and H. asiaticum hemolymph EVs, respectively. TEM and NTA revealed that the sizes of the hemolymph EVs from R. haemaphysaloides and H. asiaticum were 133 and 138 nm, respectively. Kyoto Encyclopedia of Genes and Genomes and Gene Ontology enrichment analyses of identified proteins revealed pathways related to binding, catalytic and transporter activity, translation, transport and catabolism, signal transduction and cellular community. The key EV marker proteins RhCD9, RhTSG101, Rh14-3-3 and RhGAPDH were identified using proteomics and western blot. The presence of RhFerritin-2 in tick hemolymph EVs was confirmed by western blot and immuno-electron microscopy. We demonstrated that PKH26-labeled hemolymph EVs are internalized by tick salivary glands and ovary cells in vitro. CONCLUSIONS: The results suggest that tick EVs are secreted into, and circulated by, the hemolymph. EVs may play roles in the regulation of tick development, metabolism and reproduction.


Assuntos
Vesículas Extracelulares , Rhipicephalus , Animais , Feminino , Ovário , Proteômica/métodos , Hemolinfa , Vesículas Extracelulares/química , Proteínas/metabolismo , Glândulas Salivares
10.
Insects ; 14(3)2023 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-36975979

RESUMO

Ticks are obligatory hematophagous ectoparasites and vectors of many animal and human pathogens. Chemosensation plays a significant role in tick communication with their environment, including seeking out blood meal hosts. Studies on the structure and function of Haller's organ and its components have improved our understanding regarding tick olfaction and its chemical ecology. Compared with the knowledge on insect olfaction, less is known about the molecular basis of olfaction in ticks. This review focused on the chemosensory-related candidate molecules likely involved in tick olfaction. Members of the ionotropic receptor family and a new class of odorant-binding proteins are now known to be involved in tick olfaction, which appear to differ from that of insects. These candidate molecules are more closely related to those of mites and spiders than to other arthropods. The amino acid sequences of candidate niemann-pick type C2 and microplusin-like proteins in ticks exhibit features indicating their potential role as binding proteins. In the future, more comprehensive pertinent research considering the existing shortcomings will be required to fully understand the molecular basis of tick olfactory chemoreception. This information may contribute to the development of new molecular-based control mechanisms to reduce tick populations and related disease transmission.

11.
Asian J Surg ; 46(9): 3447-3454, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37002044

RESUMO

Surgical smoke is a byproduct of aerosols containing several components produced by energy equipment. The characteristics of surgical smoke components produced by different types of tissues or using different kinds of energy devices vary. For example, the average diameter of smoke particles produced by electrocautery is smaller, and the possibility of viable cells and pathogens in surgical smoke produced by an ultrasonic knife is higher. According to the characteristics of its composition, surgical smoke may be an important risk factor affecting the health and safety of operating room staff and patients. The use of surgical masks, suction devices and portable smoke evacuation systems can reduce this risk to some extent. However, most operating room staff members do not implement corresponding measures to protect themselves. In this paper, the characteristics of surgical smoke and the research progress in protective measures are briefly reviewed.


Assuntos
Exposição Ocupacional , Salas Cirúrgicas , Humanos , Fumaça/efeitos adversos , Exposição Ocupacional/efeitos adversos
12.
Intractable Rare Dis Res ; 11(4): 202-205, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36457582

RESUMO

Perivascular epithelioid cell tumors (PEComas) are infrequent mesenchymal tumors. They are usually benign, and only a few are malignant. These tumors are more commonly found in middle-aged women. PEComas are mainly composed of differentiated perivascular epithelioid cells arranged radially around the vascular cavity, and they are usually positive for melanocyte markers and smooth muscle cell differentiation markers. Among the PEComas, hepatic PEComas generally have no obvious symptoms and no typical imaging manifestations. Malignant hepatic PEComas are even rarer. So, we explained our insights into clinical diagnosis and treatment of malignant hepatic PEComas, in order to help clinicians and pathologists to further understand PEComas.

13.
Redox Biol ; 57: 102498, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36242914

RESUMO

LncRNAs are involved in the pathophysiologic processes of multiple diseases, but little is known about their functions in hepatic ischemia/reperfusion injury (HIRI). As a novel lncRNA, the pathogenetic significance of hepatic nuclear factor 4 alpha, opposite strand (Hnf4αos) in hepatic I/R injury remains unclear. Here, differentially expressed Hnf4αos and Hnf4α antisense RNA 1 (Hnf4α-as1) were identified in liver tissues from mouse ischemia/reperfusion models and patients who underwent liver resection surgery. Hnf4αos deficiency in Hnf4αos-KO mice led to improved liver function, alleviated the inflammatory response and reduced cell death. Mechanistically, we found a regulatory role of Hnf4αos-KO in ROS metabolism through PGC1α upregulation. Hnf4αos also promoted the stability of Hnf4α mRNA through an RNA/RNA duplex, leading to the transcriptional activation of miR-23a and miR-23a depletion was required for PGC1α function in hepatoprotective effects on HIRI. Together, our findings reveal that Hnf4αos elevation in HIRI leads to severe liver damage via Hnf4αos/Hnf4α/miR-23a axis-mediated PGC1α inhibition.

14.
Scanning ; 2022: 2931686, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36042981

RESUMO

In order to solve the problem of rehabilitative physical training on ice and snow sports injuries, the author proposed an observation method using ultrasonography to be proposed. This method selects patients with anterior talofibular ligament injury treated in a hospital, forty-nine patients who did not undergo conventional rehabilitation under the surveillance of sports medicine ultrasound were set as the control group, a total of 49 patients with anterior talofibular ligament injury who underwent rehabilitation treatment under the monitoring of sports medicine ultrasound were selected as the experimental group, and the clinical efficacy of the two groups of patients was retrospectively analyzed, in order to discuss the application value of sports medicine ultrasound in the rehabilitation of anterior talofibular ligament injury. The results showed that comparing the rehabilitation effect, ankle function score, and daily living ability of the two groups of patients, the experimental group was better than the control group. Comparing the thickness of ligament and effusion between the two groups, the experimental group was also better than the control group, and the difference was statistically significant (P < 0.05). Ultrasound medical examination can help doctors to effectively judge the degree of injury and recovery of patients, and doctors can adjust the treatment plan in time according to the examination results and formulate an effective rehabilitation plan, which can greatly shorten the recovery time of patients, improve the treatment effect, promote the functional recovery of the ankle joint, and reduce the occurrence of complications.


Assuntos
Traumatismos do Tornozelo , Traumatismos em Atletas , Traumatismos do Tornozelo/diagnóstico por imagem , Traumatismos em Atletas/diagnóstico por imagem , Humanos , Gelo , Estudos Retrospectivos , Ultrassonografia/métodos
15.
Front Immunol ; 13: 892750, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35812416

RESUMO

Background: Complement factor H-related 4 (CFHR4) is a protein-coding gene that plays an essential role in multiple diseases. However, the prognostic value of CFHR4 in hepatocellular carcinoma (HCC) is unknown. Methods: Using multiple databases, we investigated CFHR4 expression levels in HCC and multiple cancers. The relationship between CFHR4 expression levels and clinicopathological variables was further analyzed. Various potential biological functions and regulatory pathways of CFHR4 in HCC were identified by performing a Gene Ontology (GO) analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis and Gene Set Enrichment Analysis (GSEA). Single-sample gene set enrichment analysis (ssGSEA) was performed to confirm the correlation between CFHR4 expression and immune cell infiltration. The correlations between CFHR4 expression levels in HCC and N6-methyladenosine (m6A) modifications and the competing endogenous RNA (ceRNA) regulatory networks were confirmed in TCGA cohort. Results: CFHR4 expression levels were significantly decreased in HCC tissues. Low CFHR4 expression in HCC tissues was significantly correlated with the patients' sex, race, age, TNM stage, pathological stage, tumor status, residual tumor, histologic grade and alpha fetal protein (AFP) level. GO and KEGG analyses revealed that differentially expressed genes related to CFHR4 may be involved in the synaptic membrane, transmembrane transporter complex, gated channel activity, chemical carcinogenesis, retinol metabolism, calcium signaling pathway, PPAR signaling pathway, insulin and gastric acid secretion. GSEA revealed that the FCGR-activated reaction, PLK1 pathway, ATR pathway, MCM pathway, cascade reactions of PI3K and FGFR1, reactant-mediated MAPK activation and FOXM1 pathway were significantly enriched in HCC with low CFHR4 expression. Moreover, CFHR4 expression was inversely correlated the levels of infiltrating Th2 cells, NK CD56bright cells and Tfh cells. In contrast, we observed positive correlations with the levels of infiltrating DCs, neutrophils, Th17 cells and mast cells. CFHR4 expression showed a strong correlation with various immunomarker groups in HCC. In addition, high CFHR4 expression significantly prolonged the overall survival (OS), disease-specific survival (DSS) and progression-free interval (PFI). We observed a substantial correlation between the expression of CFHR4 and multiple N6-methyladenosine genes in HCC and constructed potential CFHR4-related ceRNA regulatory networks. Conclusions: CFHR4 might be a potential therapeutic target for improving the HCC prognosis and is closely related to immune cell infiltration.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Adenosina/análogos & derivados , Apolipoproteínas , Biomarcadores , Carcinoma Hepatocelular/genética , Feminino , Humanos , Neoplasias Hepáticas/genética , Masculino
16.
Exp Parasitol ; 232: 108190, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34848245

RESUMO

As a widely distributed arthropod and vector for various pathogens, Hyalomma asiaticum presents great risk and potential losses in animal husbandry. Effective measures, including the use of vaccines, are necessary for controlling ticks and tick-borne diseases. A concise understanding of the tick-host interaction associated molecules and pathways is required for vaccine development. In the present study, a protein containing a single-domain von Willebrand factor type C (HaSVC) was isolated from H. asiaticum and was subjected to functional identification. As a result, the full-length sequence of the HaSVC (506 bp) gene was obtained, which putatively encodes 100 amino acids with a predicted molecular mass of 11 kDa, excluding the 23-amino acid signal peptide. HaSVC contains 8 cysteines to form 4 disulfide bonds. The native HaSVC protein was detected in multiple tick organs. HaSVC neither attenuated the anti-coagulation process nor directly affected the blood feeding of adult ticks. However, the purified recombinant protein HaSVC (rHaSVC/GST) significantly increased the proliferation of mice spleen cells. This might suggest a regulatory function for HaSVC on inflammation, thus providing new information that may explain the "crosstalk" between ticks and hosts.


Assuntos
Vetores Aracnídeos/química , Ixodidae/química , Fator de von Willebrand/química , Sequência de Aminoácidos , Animais , Anticorpos/análise , Anticorpos/metabolismo , Sequência de Bases , Coagulação Sanguínea/efeitos dos fármacos , Western Blotting , DNA Complementar/química , Feminino , Interações Hospedeiro-Parasita , Masculino , Camundongos , Interferência de RNA , Coelhos , Reação em Cadeia da Polimerase em Tempo Real , Glândulas Salivares/química , Alinhamento de Sequência , Baço/citologia , Baço/efeitos dos fármacos , Fator de von Willebrand/genética , Fator de von Willebrand/isolamento & purificação
17.
Parasit Vectors ; 14(1): 612, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34930413

RESUMO

BACKGROUND: It is well established that ecdysteroid hormones play an important role in arthropod development and reproduction, mediated by ecdysteroid receptors. Ticks are obligate hematophagous arthropods and vectors of pathogens. The salivary gland plays an essential role in tick growth and reproduction and in the transmission of pathogens to vertebrate hosts. During tick development, the salivary gland undergoes degeneration triggered by ecdysteroid hormones and activated by apoptosis. However, it is unknown how the ecdysteroid receptor and apoptosis regulate salivary gland degeneration. Here, we report the functional ecdysteroid receptor (a heterodimer of the ecdysone receptor [EcR] and ultraspiracle [USP]) isolated from the salivary gland of the tick Rhipicephalus haemaphysaloides and explore the molecular mechanism of ecdysteroid receptor regulation of salivary gland degeneration. METHODS: The full length of RhEcR and RhUSP open reading frames (ORFs) was obtained from the transcriptome. The RhEcR and RhUSP proteins were expressed in a bacterial heterologous system, Escherichia coli. Polyclonal antibodies were produced against synthetic peptides and were able to recognize recombinant and native proteins. Quantitative real-time PCR and western blot were used to detect the distribution of RhEcR, RhUSP, and RhCaspases in the R. haemaphysaloides organs. A proteomics approach was used to analyze the expression profiles of the ecdysteroid receptors, RhCaspases, and other proteins. To analyze the function of the ecdysteroid receptor, RNA interference (RNAi) was used to silence the genes in adult female ticks. Finally, the interaction of RhEcR and RhUSP was identified by heterologous co-expression assays in HEK293T cells. RESULTS: We identified the functional ecdysone receptor (RhEcR/RhUSP) of 20-hydroxyecdysone from the salivary gland of the tick R. haemaphysaloides. The RhEcR and RhUSP genes have three and two isoforms, respectively, and belong to a nuclear receptor family but with variable N-terminal A/B domains. The RhEcR gene silencing inhibited blood-feeding, blocked engorgement, and restrained salivary gland degeneration, showing the biological role of the RhEcR gene in ticks. In the ecdysteroid signaling pathway, RhEcR silencing inhibited salivary gland degeneration by suppressing caspase-dependent apoptosis. The heterologous expression in mammalian HEK293T cells showed that RhEcR1 interacts with RhUSP1 and induces caspase-dependent apoptosis. CONCLUSIONS: These data show that RhEcR has an essential role in tick physiology and represents a putative target for the control of ticks and tick-borne diseases.


Assuntos
Apoptose/fisiologia , Regulação da Expressão Gênica/fisiologia , Receptores de Esteroides/metabolismo , Rhipicephalus/metabolismo , Glândulas Salivares/fisiologia , Animais , Clonagem Molecular , Comportamento Alimentar , Feminino , Células HEK293 , Humanos , Fases de Leitura Aberta , Interferência de RNA , RNA de Cadeia Dupla , Receptores de Esteroides/genética
19.
Parasit Vectors ; 14(1): 386, 2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34348769

RESUMO

BACKGROUND: The salivary glands of female ticks degenerate rapidly by apoptosis and autophagy after feeding. Bcl-2 family proteins play an important role in the apoptosis pathways, but the functions of these proteins in ticks are unclear. We studied Bcl-2 and Bax homologs from Rhipicephalus haemaphysaloides and determined their functions in the degeneration of the salivary glands. METHODS: Two molecules containing conserved BH (Bcl-2 family homology) domains were identified and named RhBcl-2 and RhBax. After protein purification and mouse immunization, specific polyclonal antibodies (PcAb) were created in response to the recombinant proteins. Reverse transcription quantitative PCR (RT-qPCR) and western blot were used to detect the presence of RhBcl-2 and RhBax in ticks. TUNEL assays were used to determine the level of apoptosis in the salivary glands of female ticks at different feeding times after gene silencing. Co-transfection and GST pull-down assays were used to identify interactions between RhBcl-2 and RhBax. RESULTS: The RT-qPCR assay revealed that RhBax gene transcription increased significantly during feeding at all tick developmental stages (engorged larvae, nymphs, and adult females). Transcriptional levels of RhBcl-2 and RhBax increased more significantly in the female salivary glands than in other tissues post engorgement. RhBcl-2 silencing significantly inhibited tick feeding. In contrast, RhBax interference had no effect on tick feeding. TUNEL staining showed that apoptosis levels were significantly reduced after interference with RhBcl-2 expression. Co-transfection and GST pull-down assays showed that RhBcl-2 and RhBax could interact but not combine in the absence of the BH3 domain. CONCLUSIONS: This study identified the roles of RhBcl-2 and RhBax in tick salivary gland degeneration and finds that the BH3 domain is a key factor in their interactions.


Assuntos
Proteínas Proto-Oncogênicas/isolamento & purificação , Rhipicephalus/metabolismo , Proteína X Associada a bcl-2/isolamento & purificação , Animais , Apoptose , Feminino , Marcação In Situ das Extremidades Cortadas , Camundongos , Proteínas Proto-Oncogênicas/fisiologia , Glândulas Salivares/metabolismo , Glândulas Salivares/patologia , Proteína X Associada a bcl-2/fisiologia
20.
Front Cell Infect Microbiol ; 11: 713466, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34414133

RESUMO

Ticks are obligate hematophagous ectoparasites. They are important vectors for many pathogens, of both medical and veterinary importance. Antibiotic residues in animal food are known, but very little is known about the effects of antibiotic residues in animals on the microbiome diversity of ticks and tick-borne pathogen transmission. We used a Haemaphysalis longicornis-infested mouse model to evaluate the effect of antibiotic usage on tick microbiome. Nymphal ticks were fed on an antibiotic cocktail-treated or water control mice. Adult ticks molted from nymphs fed on the antibiotic cocktail-treated mouse had a dysbiosed microbiota. Nymphal ticks were also fed on a B. microti-infected mice that had been treated with antibiotic cocktail or water. We found that the B. microti infection in adult ticks with a dysbiosed microbiota (44.7%) was increased compared with the control adult ticks (24.2%) by using qPCR targeting 18S rRNA gene. This may increase the risk of tick-borne pathogens (TBPs) transmission from adult ticks to a vertebrate host. These results show that an antibiotic-treated mouse can induce tick microbiota dysbiosis. Antibiotic treatment of B. microti-infected mouse poses the possibility of increasing transstadial transmission of B. microti from the nymph to the adult H. longicornis. These findings suggest that B. microti transmission may be exacerbated in high antibiotic usage areas.


Assuntos
Babesia microti , Microbiota , Carrapatos , Animais , Disbiose , Camundongos , Ninfa
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