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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. [ABSTRACT FROM AUTHOR]

The excellent water-cooling structure contributes to achieve efficient and reasonable heat transfer in mold, which is indispensable to realize billet high-speed continuous casting. Therefore, five kinds of unconventional cooling structures were designed, and the corresponding three-dimensional molten steel–mold–cooling water models coupled with flow, heat transfer, and solidification were established based on them. Then, the accuracy of models was verified by comparing heat flux with other studies. Finally, the temperature distribution characteristics in models under high casting speed were analyzed mainly, and the optimal water-cooling structure was proposed. The results show that high casting speed is beneficial to uniform the temperature of the strand, but will greatly reduce its thickness. Compared with other structures, the composite structure consisting of water seam and water channel has the best cooling effect. By using this water-cooling structure, the maximum hot face temperature of copper tube will reduce to 469 K and make mold temperature distribution more uniform at 6.5 m min−1. Meanwhile, it can take away 5.58 pct more heat than conventional water seam in the process of molten steel passing through mold. Therefore, mold with water seam and water channel can further improve the production efficiency on the premise of ensuring the quality of the strand. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Inhibitors of apoptosis (IAPs) are regulators of cell death and may play a role in the salivary glands of ticks during blood-feeding. We cloned the open reading frame (ORF) sequence of the IAP gene in Rhipicephalus haemaphysaloides (RhIAP). The RhIAP ORF of 1887 bp encodes a predicted protein of 607 amino acids, which contains three baculovirus IAP repeat domains and a RING finger motif. A real-time PCR assay showed that RhIAP mRNA was expressed in all the tick developmental stages (eggs, larvae, nymphs, and adults) and in all tissues examined (midgut, ovary, salivary glands, fat body, and hemolymph). Western blot showed that the protein level of RhIAP in salivary glands increased during tick blood-feeding and decreased towards the end of tick engorgement. RhIAP gene silencing in vitro experiments with salivary glands demonstrated that RhIAP could be effectively knocked down within 48 h after dsRNA treatment, and as a consequence, salivary glands displayed apoptotic morphology. RhIAP gene silencing also inhibited tick blood-feeding and decreased the engorgement rate. These data suggest that RhIAP might be a suitable RNAi target for tick control. [ABSTRACT FROM AUTHOR]

Babesiosis is a tick-borne protozoonosis caused by Babesia, which can cause fever, hemolytic anemia, hemoglobinuria, and even death. Babesia microti is a parasite found in rodents and can be pathogenic to humans. In this study, the full-length cDNA of a B. microti cysteine protease (BmCYP) was expressed and the recombinant rBmCYP protein analyzed and characterized. BmCYP is encoded by an ORF of 1.3 kb, with a predicted molecular weight of 50 kDa and a theoretical pI of 8.5. The amino acid sequence of BmCYP exhibits an identity of 32.9 to 35.2% with cysteine proteases of Babesia ovis, Babesia bovis, and Theileria, respectively. The results of the proteinase assays show that rBmCYP has cysteine protease enzymatic activity. In addition, we demonstrate that tick cystatins rRhcyst-1 and rRhcyst-2 were able to effectively inhibit the activity of rBmCYP; the inhibition rates were 57.2% and 30.9%, respectively. Tick cystatins Rhcyst-1 and Rhcyst-2 were differentially expressed in ticks that fed on Babesia-infected mice relative to non-infected control ticks. Our results suggest that BmCYP is a functional enzyme with cysteine protease enzymatic activity and may be involved in tick-B. microti interactions. [ABSTRACT FROM AUTHOR]

Clathrin plays an important role in arthropods, but its function in ticks has not been explored. Here, we describe the molecular characteristics of the clathrin heavy chain of the tick Rhipicephalus haemaphysaloides and its effects on yolk development. The open reading frame of the clathrin heavy chain (Chc) (Rh-Chc) gene consists of 5103 nucleotides encoding 670 amino acids, which is most closely related to that of Ixodes scapularis and relatively close to Homo sapiens and Drosophila melanogaster. Real-time qPCR revealed that Rh-Chc was expressed at all developmental stages and organs. After Rh-Chc is silenced, ticks did not feed and mortality rate was 100%. Moreover, Rh-Chc co-localized with Vitellogenin receptor (VgR) on oocyte membrane. Immunofluorescence showed that the expression of Vitellogenin (Vg) (Rh-Vg) was also closely related to Rh-Chc. Immunofluorescence showed that the expression of Vg was also closely related to Rh-Chc, Rh-Chc silencing slowed the development of oocytes in tick, and culture of ovary in vitro silenced Rh-Chc, the development of oocytes in ticks also slowed down. Overall, the results of this study indicated that Rh-Chc is a vital gene in the tick R. haemaphysaloides that plays an important role in its growth, development, and reproduction. [ABSTRACT FROM AUTHOR]

Heat shock cognate 70-kDa protein (RH-Hsc70) was identified from a cDNA library synthesized from the sialotranscriptomes of unfed and fed Rhipicephalus haemaphysaloides. The RH-Hsc70 open reading frame is 1950 bp long and encodes a protein that is 649 amino acids in length, with a predicted molecular weight of 71.1 kDa and a theoretical pI of 5.43. RH-Hsc70 exhibits 98% amino acid identity with Hsc70 in Haemaphysalis flava and 83% identity with Hsc70 in arthropods and mammals. RH-Hsc70 was mainly expressed in nymphs and adult ticks, not in larvae. Real-time quantitative PCR analysis indicated that RH-Hsc70 mRNA expression was induced by blood feeding in adult ticks. In addition, RH-Hsc70 gene expression was higher in the ovaries of fed adult ticks than that in the midguts, salivary glands, and fat bodies of unfed or fed adult ticks. RH-Hsc70 gene knockdown inhibited tick blood feeding, significantly decreased tick engorgement rate, and increased tick death rate. These data illustrate the importance of RH-Hsc70 in tick blood feeding and aging, which makes it a promising candidate for the development of anti-tick vaccines. [ABSTRACT FROM AUTHOR]

A multilevel fuzzy comprehensive evaluation approach based on multi-objective decision theory is used to assess tool cutting performance during the machining of titanium alloy. This includes an exponential scale of AHP weights for each index. We studied two different kinds of cutting tools, one with an applied micro-texture and conducted a comprehensive evaluation of their performance when engaged in the ordinary milling of titanium alloy. This was based on surface roughness, surface hardening, chip formation, and tool wear. We also undertook a comparison of the required cutting force and cutting temperature. The results show that in the process of cutting titanium alloy, the micro-texture of the surface has an anti-wear effect and stores impurities. This can improve a cutting tool’s workpiece and chip contact environment as well as its actual processing performance. The overall evaluation value for a micro-textured ball end milling cutter was found to be 0.62. Against this, the value for a common milling cutter was 0.38. These results form an important basis for improving the machinability of titanium alloy. [ABSTRACT FROM AUTHOR]

Numerical experiments are used in this study to systematically investigate the effects of convergence rate, crustal rheological strength, and lithospheric thermal structure on the dynamics of continental collision. The study focuses on the types, conditions and processes of unstable continental subduction. Modelling results suggest that the development of unstable continental subduction can be promoted by conditions that tend to decrease rheological strength of the lithosphere, such as low crustal rheological strength, 'hot' thermal structure of the lithosphere, or low convergence rate. Unstable subduction mode can be further categorized into three types: (1) multi-stage slab breakoff, (2) continuously 'flowing' of fluid-like slab into the upper mantle, and (3) large-scale detachment of the thickened orogenic root. These three types of unstable continental subduction are respectively associated with (1) a low convergence rate, (2) 'hot' thermal structure of the lithosphere with a high convergence rate, and (3) moderate-high crustal rheological strength with a low convergence rate. It is also revealed that the evolution of crustal melting is dominated by the deformation pattern of continental collision, which is mainly controlled by crustal rheological strength. The modelling results have important implications for understanding of continental subduction mode selection under specific geodynamic conditions. [ABSTRACT FROM AUTHOR]

Kunitz/bovine pancreatic trypsin inhibitor proteins are abundant in the salivary glands of ticks and perform multiple functions in blood feeding, including inhibiting blood coagulation, regulating host blood supply and disrupting host angiogenesis. In this study, we identified a novel gene designated HA11 ( Hyalomma asiaticum 11 kDa protein) from the salivary gland of the tick H. asiaticum. HA11 is encoded by a gene with an open reading frame of 306 bp that is translated into a deduced 101 amino acid 11 kDa protein that shares 27% sequence identity with a Kunitz-like protease inhibitor precursor in Amblyomma variegatum. Bioinformatic analysis confirmed HA11 as a member of the Kunitz-type family of inhibitors. Real time-PCR detected HA11 mRNA transcripts in tick larvae and nymphae stages, with levels highest in salivary gland tissue, and transcription was induced by blood feeding. HA11 anticoagulant activity was demonstrated by its ability to delay normal clotting of rabbit plasma in an activated partial thromboplastin time assay. Furthermore, RNA interference confirmed that HA11 influences H. asiaticum development and blood feeding, and the recombinant protein exerted low hemolytic activity. These results suggest HA11 is a novel Kunitz-type anticoagulant protein involved in tick blood feeding that may have potential as an anticoagulant drug or vaccine. [ABSTRACT FROM AUTHOR]

Babesia microti is the primary causative agent of human babesiosis worldwide and associated with increased human health risks and the safety of blood supply. The parasite replicates in the host's red blood cells, thus, in order to counteract the oxidative stress and toxic effects, parasites employ a thioredoxin (Trx) system to maintain a redox balance. Since thioredoxin reductase (TrxR) plays a critical role in the system, in this study, we report the cloning, expression, and functional characterization of a novel TrxR from B. microti (BmiTrxR). The complete gene BmiTrxR was obtained by amplifying the 5′ and 3′ regions of messenger RNA (mRNA) by RACE. The full-length complementary DNA (cDNA) of BmiTrxR was 1766 bp and contained an intact open reading frame with 1662 bp that encoded a polypeptide with 553 amino acids. Molecular weight of the predicted protein was 58.4 kDa with an isoelectric point of 6.95, similar to high molecular weight TrxR. The recombinant protein of BmiTrxR was expressed in a His-fused soluble form in Escherichia coli. The native protein BmiTrxR was identified with the mouse anti-BmiTrxR polyclonal serum by western blotting and IFAT. Moreover, the enzyme showed a disulfide reductase activity using DTNB as substrate and catalyzed the NADPH-dependent reduction of Trx. Auranofin, a known inhibitor of TrxR, completely abrogated the activity of the recombinant enzyme in vitro. These results not only contribute to the understanding of redox pathway in this parasite but also suggest that BmiTrxR could be a potential target for the development of novel strategies to control B. microti thus reducing the incidence of babesiosis. [ABSTRACT FROM AUTHOR]

Subolesin is a well-characterized protective antigen in many ticks and, thus, it is potentially useful in the development of a broad-spectrum vaccine or an autocidal gene silencing strategy to control tick infestations. A subolesin homolog was cloned from the tick Rhipicephalus haemaphysaloides, which is widespread in China, by rapid amplification of complementary DNA (cDNA) ends. Its full-length cDNA was 1386 base pairs (bp), containing a 483 bp open reading frame with a predicted molecular mass of 18.7 kilodaltons and an isoelectric point of 9.26. The subolesin protein had a typical nuclear localization signal in its amino-terminus. The full-length cDNA of R. haemaphysaloides showed 52 and 80 % identities to those from Ixodes scapularis and R. microplus, respectively, whereas amino acid sequence alignments showed 80 and 97 % identities, respectively. Native subolesin was recognized in the unfed tick midgut by an antibody against recombinant subolesin. Transcriptional analysis showed that subolesin was expressed in the tick's four developmental stages and in all of the tissues examined, except for the synganglion. The pathogen Babesia microti induced the subolesin transcript by fourfold. Subolesin gene silencing by RNA interference significantly decreased the larval engorgement rate, the attachment rate and body weight of engorged nymphs, and the body weight and attachment and engorgement rates of adults, as well as the egg weight per female tick. Vaccinating mice and rabbits with recombinant subolesin induced a significant protective effect, resulting in a reduction of blood feeding and oviposition. These results encourage further studies of using subolesin to control tick infestations in China. [ABSTRACT FROM AUTHOR]

A novel cystatin, designated RHcyst-2, was isolated from the tick Rhipicephalus haemaphysaloides. The full-length cDNA of RHcyst-2 is 773 bp, including an intact open reading frame encoding an expected protein of 139 amino acids and consisting of a 23 amino acids signal peptide. Predicted RHcyst-2 mature protein molecular weight is about 13 kDa, isoelectric point is 4.96. A sequence analysis showed that it has significant homology with the known type 2 cystatins. The recombinant protein of RHcyst-2 was expressed in a glutathione S-transferase-fused soluble form in Escherichia coli, and its inhibitory activity against cathepsin L, B, C, H, and S, as well as papain, was identified by fluorogenic substrate analysis. The results showed that rRHcyst-2 can effectively inhibit the six cysteine proteases' enzyme activities. An investigation of the RHcyst-2 genes' expression profile by quantitative reverse transcription-PCR demonstrated that it was more richly transcribed in the embryo (egg) stage and mainly distributed in the mid-gut of adult ticks. Western blot analysis confirmed that RHcyst-2 was secreted into tick saliva. [ABSTRACT FROM AUTHOR]

Ticks encounter various microbes while sucking blood from an infected host and carrying these pathogens in themselves. Ticks can then transmit these pathogens to vertebrate hosts. The immune system of ticks can be stimulated to produce many bioactive molecules during feeding and pathogen invasion. Antimicrobial peptides (AMPs) are key effector molecules of a tick's immune response, as they can kill invading pathogenic microorganisms. In this study, we identified a novel cysteine-rich AMP, designated Rhamp1, in the salivary glands of unfed and fed female ticks ( Rhipicephalus haemaphysaloides). Rhamp1 is encoded by a gene with an open reading frame of 333 bp, which in turn encodes a peptide of 12 kDa with a 22 amino acid residue signal peptide. The Rhamp1 protein had a pI of 8.6 and contained six conserved cysteine residues at the C-terminus. Rhamp1 shared 43 % amino acid identity with a secreted cysteine-rich protein of another tick species, Ixodes scapularis. We cloned the Rhamp1 gene and attempted to express a recombinant protein using prokaryotic and eukaryotic systems, to determine its biological significance. Recombinant Rhamp1 was successfully expressed in both systems, yielding a glutathione S-transferase (GST)-tagged protein (36 kDa) from the prokaryotic system, and a polyhistidine-tagged Rhamp1 protein (14 kDa) from the eukaryotic system. Rhamp1 inhibited the activities of chymotrypsin (16 %) and elastase (22 %) and exerted low hemolytic activity. It also inhibited the growth of Gram-negative bacteria, including Pseudomonas aeruginosa (49 %), Salmonella typhimurium (50 %), and Escherichia coli (52 %). Our findings suggest that Rhamp1 is a novel AMP in R. haemaphysaloides with the ability to inhibit proteinase activity. [ABSTRACT FROM AUTHOR]

Different molecular detection methods require diverse molecular platforms, but there is no uniform standard for people to reference in the detection of Trichinella. In this study, real-time PCR, loop-mediated isothermal amplification (LAMP), and conventional PCR were developed for the detection of Trichinella by targeting mitochondrial large subunit ribosomal DNA (mt-lsrDNA). We compared the performance of the three newly developed assays. The results revealed that the detection limits of the real-time PCR, LAMP, and conventional PCR assays were 10 and 100 fg/μL and 1 pg/μL of Trichinella spiralis genomic DNA, respectively. The assays were used in the detection of Trichinella in the field. A total of 192 samples were obtained from pigs: 75 samples from free range farming and 117 from intensive feeding factory. The infection rate was 8/192 (4.2 %), 7/192 (3.6 %), and 1/192 (1.0 %) through the real-time PCR, LAMP, and conventional PCR assays, respectively. These data indicate that Taqman real-time PCR was a rapid, specific, and sensitive tool as a preferred option for investigation of valuable samples, but that LAMP assay was closed tube, highly sensitive, cost-effective, rapid, easy-to-perform, and was the optimal choice for detection of Trichinella in the field. The results of a model of experimental infection in mice indicated that spleen can be used as sampling site for the detection of early T. spiralis infection. However, the diaphragm and myocardium were the most suitable sampling sites for the detection of T. spiralis. [ABSTRACT FROM AUTHOR]

The salivary glands are vital to the biological success of ticks and they are a major route of pathogen transmission. Tick salivary glands undergo remarkable growth and differentiation during the blood-feeding period. MicroRNAs (miRNAs) are noncoding small RNA molecules found in diverse organisms that regulate gene expression at the post-transcriptional level. To explore transcriptional differences in the miRNAs of fed and unfed tick ( Haemaphysalis longicornis) salivary glands, we investigated small RNA (sRNA) transcriptomes derived from the salivary glands and made a comparative analysis of miRNA profiles related to tick blood-feeding in the salivary glands. We generated two small RNA libraries from the salivary glands of unfed and fed H. longicornis, and obtained 14.8 and 10.3 million reads of 18-30 nt, respectively. The unfed-specific sRNAs were clearly richer than the fed-specific sRNAs in terms of the unique and total sRNAs. Overall, 769 conserved miRNA families were found in unfed samples, whereas 440 conserved miRNA families were found in fed samples. Six of the ten most abundant miRNA were found in both the unfed and fed tick salivary glands, i.e., miR-1, miR-375, bantam, miR-184, miR-739, and miR-263a. We found that known miRNA homologs displayed a wide variety of expression profiles in unfed and fed tick salivary glands. After blood-feeding, 162 known miRNAs were upregulated. The six main upregulated miRNAs were mir-1810, mir-2138, mir-2140, mir-425*, mir-429, and mir-516*. Likewise, 231 known miRNAs were downregulated after blood-feeding. The six main downregulated miRNAs were miR-2941-1*, miR-10-5p, miR-2973, miR-1183, miR-4006b-5p, and miR-881. We found that distinct microRNA profiles in the salivary glands of H. longicornis were relating to tick blood feeding. The differential expression of miRNAs in unfed and fed tick salivary glands supported their involvement at new levels in the regulation of tick blood-feeding. Our data provide an important resource for a more detailed functional analysis of miRNAs in this species. [ABSTRACT FROM AUTHOR]

Nanoporous copper (NPC) ribbons were synthesized by free corrosion dealloying of Al-Cu alloy ribbons prepared by single-roller melt spinning processing equipment for precursor samples. The components and microstructures of NPC were characterized by utilizing X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and energy dispersive X-ray (EDS) analysis. The results show that, the microstructures of the NPC ribbons strongly depend upon the phase constitutions of the starting Al-Cu alloys. In dealloying, Al atoms in the α-Al phase and AlCu phase can be easily etched off, resulting in the formation of NPC with a homogeneous porous structure, while the AlCu phase can hardly be eroded. Moreover, etching solution and annealing process also have important effects on the dealloying process and morphology of the NPC ribbons. [ABSTRACT FROM AUTHOR]