Enhancing miR-19a/b induced cardiomyocyte proliferation in infarcted hearts by alleviating oxidant stress and controlling miR-19 release.

Fully restoring the lost population of cardiomyocytes and heart function remains the greatest challenge in cardiac repair post myocardial infarction. In this study, a pioneered highly ROS-eliminating hydrogel was designed to enhance miR-19a/b induced cardiomyocyte proliferation by lowering the oxidative stress and continuously releasing miR-19a/b in infarcted myocardium in situ. In vivo lineage tracing revealed that ∼20.47 % of adult cardiomyocytes at the injected sites underwent cell division in MI mice. In MI pig the infarcted size was significantly reduced from 40 % to 18 %, and thereby marked improvement of cardiac function and increased muscle mass. Most importantly, our treatment solved the challenge of animal death--all the treated pigs managed to live until their hearts were harvested at day 50. Therefore, our strategy provides clinical conversion advantages and safety for healing damaged hearts and restoring heart function post MI, which will be a powerful tool to battle cardiovascular diseases in patients.

Bioactive constituents from Clerodendrum trichotomum and their α-glucosidase inhibitory and PPAR-γ agonist activities.

Three new neoclerodane diterpenoids (1-3), two new steroids (4-5), one new monoterpene (6), one new derivative of benzaldehyde (7) and one new iridoid glycoside (8), along with 19 known phenolic compounds, were isolated from Clerodendrum trichotomum. Their structures were established by a combination of detailed spectroscopic analyses (1D and 2D NMR) and high resolution electrospray ionization mass spectroscopy (HRESIMS). The isolated compounds were screened on α-glucosidase inhibitory and the peroxisome proliferator-activated receptor gamma (PPAR-γ) agonist activities, and the results showed that three phenylethanoid glycosides, verbascoside (9), leucosceptoside a (10), and isoacteoside (13), and two flavonoids, apigenin (22) and luteolin (26) showed potent inhibitory effects against α-glucosidase, with IC50 values in the range from 15 to 700 µM. In addition, four flavonoids apigenin 7-O-ß-D-glucuronide (19), apigenin (22), luteolin (26), and quercetin (27) exhibited significant PPAR-γ agonistic activities with EC50 values in the range 2.3-24.9 µM.

Withaferin a modulation of microglia autophagy mitigates neuroinflammation and enhances cognitive function in POCD.

With the aging process of the global population and the development of medical technology, the cases of postoperative cognitive dysfunction (POCD) are also increasing. Due to the complexity of the pathogenesis, urgent treatment has been sought. Neuroinflammation induced by the accumulation of lipid droplets (LDs) in microglia has been closely watched in recent years and is also considered to be an important cause of nerve damage. Our study found that derived from Withania somnifera, Withaferin A (WA) could reduce the accumulation of LDs in the hippocampus of POCD mice, inhibit the expression of inflammatory factor interleukin-1ß (IL-1ß), and improve the cognitive ability of mice. Further in vitro experimental studies showed that WA increased the autophagy level of microglia, promoted the degradation of LDs, and reduced the production of inflammatory factors. In this regard, our comprehensive research endeavor holds the potential to furnish novel insights into therapeutic strategies aimed at addressing POCD and its associated neural impairments.

Closed-loop theranostic microgels for immune microenvironment modulation and microbiota remodeling in ulcerative colitis.

Inflammatory bowel disease (IBD) is characterized by the upregulation of reactive oxygen species (ROS) and dysfunction of gut immune system, and microbiota. The conventional treatments mainly focus on symptom control with medication by overuse of drugs. There is an urgent need to develop a closed-loop strategy that combines in situ monitoring and precise treatment. Herein, we innovatively designed the 'cluster munition structure' theranostic microgels to realize the monitoring and therapy for ulcerative colitis (a subtype of IBD). The superoxide anion specific probe (tetraphenylethylene-coelenterazine, TPC) and ROS-responsive nanogels consisting of postbiotics urolithin A (UA) were loaded into alginate and ion-crosslinked to obtain the theranostic microgels. The theranostic microgels could be delivered to the inflammatory site, where the environment-triggered breakup of the microgels and release of the nanogels were achieved in sequence. The TPC-UA group had optimal results in reducing inflammation, repairing colonic epithelial tissue, and remodeling microbiota, leading to inflammation amelioration and recovery of tight junction between the colonic epithelium, and maintenance of gut microbiota. During the recovery process, the local chemiluminescence intensity, which is proportional to the degree of inflammation, was gradually inhibited. The cluster munition of theranostic microgels displayed promising outcomes in monitoring inflammation and precise therapy, and demonstrated the potential for inflammatory disease management.

Progress in the Pathogenesis of Diabetic Encephalopathy: The Key Role of Neuroinflammation.

Diabetic encephalopathy (DE) is a severe complication that occurs in the central nervous system (CNS) and leads to cognitive impairment. DE involves various pathophysiological processes, and its pathogenesis is still unclear. This review summarised current research on the pathogenesis of diabetic encephalopathy, which involves neuroinflammation, oxidative stress, iron homoeostasis, blood-brain barrier disruption, altered gut microbiota, insulin resistance, etc. Among these pathological mechanisms, neuroinflammation has been focused on. This paper summarises some of the molecular mechanisms involved in neuroinflammation, including the Mammalian Target of Rapamycin (mTOR), Lipocalin-2 (LCN-2), Pyroptosis, Advanced Glycosylation End Products (AGEs), and some common pro-inflammatory factors. In addition, we discuss recent advances in the study of potential therapeutic targets for the treatment of DE against neuroinflammation. The current research on the pathogenesis of DE is progressing slowly, and more research is needed in the future. Further study of neuroinflammation as a mechanism is conducive to the discovery of more effective treatments for DE in the future.

Exploring the heterogeneity of interstitial cells of Cajal and their properties in gastrointestinal mesenchymal tumors applying single-cell RNA sequencing analysis.

BACKGROUND: Gastrointestinal mesenchymal stromal tumors (GISTs) are a group of intramural tumors that exhibit a wide range of morphologies. Dysfunction or loss of interstitial cells of Cajal (ICCs) is correlated with the disorders of gastrointestinal motility. At present, the characterization and molecular mechanisms underlying the role of ICCs in GIST are still not clear. METHODS: The GSE162115 dataset from Gene Expression Omnibus database was processed using Seurat package for quality control, data normalization, and cell clustering. Differential expression and functional enrichment analyses were performed using the FindAllMarkers function and clusterProfiler package. Cellular heterogeneity was assessed by CytoTRACE and potential regulatory mechanisms of ICCs in GISTs were investigated using SCENIC. Cellular communication was inferred and analyzed applying the CellChat package. RESULTS: Eight clusters were identified based on 34,861 cells. Intra-tumor samples had a higher proportion of ICCs than peri-tumor. ICCs were related to cell cycle and glycolytic activity in intra-tumor samples, while those in peri-tumor samples were involved in immune response. Further analysis identified four ICC subgroups (subcluster 1-4), of which subcluster 3 showed the most typical stem cell properties and interacted with the rest of the cells through the MIF-CD74 (CD44) protein. CONCLUSION: This study analyzed the heterogeneity and stem cell properties of ICCs in GISTs, revealing the molecular mechanisms and potential therapeutic targets for GISTs.

Effective treatment of traumatic brain injury by injection of a selenium-containing ointment.

Traumatic brain injury (TBI) is an incurable and overwhelming disease accompanied with serve disability and huge financial burden, where the overproduced reactive oxygen species (ROS) can exacerbate the secondary injury, leading to massive apoptosis of neurons. In this study, ß-cyclodextrin (CD)-capped hyperbranched polymers containing selenium element (HSE-CD) were crosslinked with CD-modified hyaluronic acid (HA-CD) and amantadine-modified hyaluronic acid (HA-AD) to obtain a ROS-responsive ointment (R-O). The structures of synthesized polymers were characterized with 1H nuclear magnetic resonance, and the properties of ointment were investigated with rheology and antioxidation. Compared to non-ROS-responsive ointment (N-O), the R-O ointment had stronger efficiency in decreasing the ROS level in BV2 cells in vitro. In a controlled rat cortical impact (CCI) model, the R-O ointment could relieve the DNA damage and decrease apoptosis in injured area via reducing the ROS level. Besides, after the R-O treatment, the rats showed significantly less activated astrocytes and microglia, a lower level of pro-inflammatory cytokines and a higher ratio of M2/M1 macrophage and microglia. Moreover, compared to the TBI group the R-O ointment promoted the doublecortin (DCX) expression and tissue structure integrity around the cavity, and promoted the recovery of nerve function post TBI. STATEMENT OF SIGNIFICANCE: Traumatic brain injury (TBI) is an incurable and overwhelming disease, leading to severe disability and huge social burden, where reactive oxygen species (ROS) are considered as one of the most significant factors in the secondary injury of TBI. A ROS responsive supramolecular ointment containing di-selenide bonds was injected in rats with controlled cortical impact. It relieved the DNA damage and decreased apoptosis in the injured area via reducing the ROS levels, downregulated neuroinflammation, and improved neurological recovery of TBI in vivo. This designed self-adaptive biomaterial effectively regulated the pathological microenvironment in injured tissue, and achieved better therapeutic effect.

Relief effect of biochar on continuous cropping of tobacco through the reduction of p-hydroxybenzoic acid in soil.

Biochar application to soil has proven to be an excellent approach for decreasing the concentration of auto-toxic compounds and promoting plant growth in continuous-cropping fields. However, the mechanisms underlying the action pathway among biochars, auto-toxic compounds and tobacco remain unknown. In this study, we conducted an experiment tracking the incidence rate of black rot and auto-toxic compounds for a 3-year continuous-cropping tobacco pot trial in response to biochar treatment intensity compared with that of non-biochar treatment. Biochar inhibited the incidence of black rot. Using ultra-high-performance liquid chromatography-mass spectrometry (UPLC‒MS/MS), we revealed that biochar can effectively decrease the concentration of p-hydroxybenzoic acid (PHA), which is associated with the incidence rate of black rot (R2 = 0.890, p < 0.05). The sorption kinetics and isotherm of PHA sorption on biochar indicate that the coexistence of heterogeneous and monolayer sorption plays an important role in the adsorption process. Using Molecular dynamics (MD), Density functional theory (DFT) and Independent gradient model (IGM) analyses, we provide evidence that van der Waals force (vdW), π-π bonds and H-bonds between biochar and PHAs are the dominant factors that affect adsorption capacity. Moreover, the molecular adsorption rate (Nbiochar: NPHAs = 1:4) was theoretically calculated. In contrast, biochar dramatically increased nutrient retention capacity and improved soil properties, further enhancing tobacco quality, including its agronomic and physiological traits. Therefore, we considered that biochar not only relieved continuous cropping but also improved soil properties suitable for tobacco growth. Together, we demonstrate that the action of biochar in continuously cropped soil improves soil traits and alleviates auto-toxic compound toxicity. These data contribute to the direction of modified biochar application to improve continuous-cropping soil.

Activating transcription factor 6 contributes to cisplatin­induced ototoxicity via regulating the unfolded proteins response.

As a broad-spectrum anticancer drug, cisplatin is widely used in the treatment of tumors in various systems. Unfortunately, several serious side effects of cisplatin limit its clinical application, the most common of which are nephrotoxicity and ototoxicity. Studies have shown that cochlear hair cell degeneration is the main cause of cisplatin-induced hearing loss. However, the mechanism of cisplatin-induced hair cell death remains unclear. The present study aimed to explore the potential role of activating transcription factor 6 (ATF6), an endoplasmic reticulum (ER)-localized protein, on cisplatin-induced ototoxicity in vivo and in vitro. In this study, we observed that cisplatin exposure induced apoptosis of mouse auditory OC-1 cells, accompanied by a significant increase in the expression of ATF6 and C/EBP homologous protein (CHOP). In cell or cochlear culture models, treatment with an ATF6 agonist, an ER homeostasis regulator, significantly ameliorated cisplatin-induced cytotoxicity. Further, our in vivo experiments showed that subcutaneous injection of an ATF6 agonist almost completely prevented outer hair cell loss and significantly alleviated cisplatin-induced auditory brainstem response (ABR) threshold elevation in mice. Collectively, our results revealed the underlying mechanism by which activation of ATF6 significantly improved cisplatin-induced hair cell apoptosis, at least in part by inhibiting apoptosis signal-regulating kinase 1 expression, and demonstrated that pharmacological activation of ATF6-mediated unfolded protein response is a potential treatment for cisplatin-induced ototoxicity.

Harvesting Vibration Energy for Efficient Cocatalyst-Free Sonocatalytic H2 Production over Magnetically Separable Ultra-Low-Cost Fe3O4.

The cavitation effect is an important geochemical phenomenon, which generally exists under strong hydrodynamic conditions. Therefore, developing an economical and effective sonocatalyst becomes a vital method in capitalizing on the cavitation effect for energy generation. In this study, we first report a novel Fe3O4 sonocatalyst that can be easily separated using a magnetic field and does not require any additional cocatalysts for H2 production from H2O. When subjected to ultrasonic vibration, this catalyst achieves an impressive H2 production rate of up to 175 µmol/h/USD (where USD stands for dollars), surpassing most previously reported mechanical catalytic materials. Furthermore, the ease and efficiency of separating this catalyst using an external magnetic field, coupled with its effortless recovery, highlight its significant potential for practical applications. By addressing the key limitations of conventional sonocatalysts, our study not only demonstrates the feasibility of using Fe3O4 as a highly efficient sonocatalyst but also showcases the exciting possibility of using a new class of magnetically separable sonocatalysts to productively transform mechanical energy into chemical energy.

Effects of bone marrow mesenchymal stem cell-conditioned medium on the proliferation and migration of liposarcoma cells.

INTRODUCTION: Liposarcoma constitutes a prevalent subtype of soft tissue sarcoma, represents approximately 20% of all sarcomas. However, conventional chemotherapeutic agents have shown restricted effectiveness in treating liposarcoma patients. Accumulating evidence indicates that mesenchymal stem cells (MSCs) have the characteristic of migration to tumor site, promote or suppress tumors. How human bone marrow mesenchymal stem cells (BMSCs) contribute to liposarcoma phenotype remains poorly understood. This study aims to investigate the effects of human bone marrow mesenchymal stem cell-conditioned medium (BMSC-CM) on the proliferation and migration of liposarcoma cell lines 93T449 and SW872, as well as explore potential underlying mechanisms of BMSC-CM action on these cells. MATERIALS AND METHODS: We transfected BMSCs with lentiviral constructs to knock down the transcriptional co-activator Yes-associated protein 1 (YAP1), conditioned medium (CM) obtained from BMSCs and shYAP1-BMSC, respectively. Liposarcoma cell lines 93T449 and SW872 were co-cultured with BMSC-CM or shYAP1-BMSC-CM. Cell proliferation ability was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell apoptosis was evaluated using flow cytometric assay. A wound healing assay was used to analyze cell migration. The expression levels of YAP1, Bcl-2, and matrix metalloproteinase-2 (MMP-2) were determined by western blot assay. RESULTS: Co-culturing liposarcoma cell lines 93T449 and SW872 with BMSC-CM promoted tumor cell proliferation, while shYAP1-BMSC-CM significantly inhibited cell viability and migration, induced apoptosis, and downregulated Bcl-2 and MMP-2 expression. CONCLUSIONS: These findings provide new insights into the impact of BMSC-CM on liposarcoma and suggest its possible involvement in liposarcoma cell growth.

Olfactory ensheathing cells as candidate cells for chronic pain treatment.

Chronic pain is often accompanied by tissue damage and pain hypersensitivity. It easily relapses and is challenging to cure, which seriously affects the patients' quality of life and is an urgent problem to be solved. Current treatment methods primarily rely on morphine drugs, which do not address the underlying nerve injury and may cause adverse reactions. Therefore, in recent years, scientists have shifted their focus from chronic pain treatment to cell transplantation. This review describes the classification and mechanism of chronic pain through the introduction of the characteristics of olfactory ensheathing cells (OECs), an in-depth discussion of special glial cells through the phagocytosis of nerve debris, receptor-ligand interactions, providing nutrition, and other inhibition of neuroinflammation, and ultimately supporting axon regeneration and mitigation of chronic pain. This review summarizes the potential and limitations of OECs for treating chronic pain by objectively analyzing relevant clinical trials and methods to enhance efficacy and future development prospects.

Defect Engineered Microcrystalline Cellulose for Enhanced Cocatalyst-Free Piezo-Catalytic H2 Production.

Mechanical energy driven piezocatalytic hydrogen (H2 ) production is a promising way to solve the energy crisis . But limited by the slow separation and transfer efficiency of piezoelectric charges generated on the surface of piezocatalysts , the piezocatalytic performance is still not satisfactory. Here, defect engineering is first used to optimize the piezocatalytic performance of microcrystalline cellulose (MCC). The piezocatalytic H2 production rate of MCC with the optimal defect concentration can reach up to 84.47 µmol g-1 h-1 under ultrasonic vibration without any co-catalyst, which is ≈3.74 times higher than that of the pure MCC (22.65 µmol g-1 h-1 ). The enhanced H2 production rate by piezoelectric catalysis is mainly due to the introduction of defect engineering on MCC, which disorders the symmetry of MCC crystal structure, improves the electrical conductivity of the material, and accelerates the separation and transfer efficiency of piezoelectric charges. Moreover, the piezocatalytic H2 production rate of MCC with the optimal defect concentration can still reach up to 93.61 µmol g-1 h-1 in natural seawater, showingits commendable practicability. This study presents a novel view for designing marvelous-performance biomass piezocatalysts through defect engineering, which can efficiently convert mechanical energy into chemical energy .

Partially brain effects of injection of human umbilical cord mesenchymal stem cells at injury sites in a mouse model of thoracic spinal cord contusion.

Purpose: The pain caused by spinal cord injury (SCI) poses a major burden on patients, and pain management is becoming a focus of treatment. Few reports have described changes in the brain after SCI. Particularly, the exact mechanism through which brain regions affect post-injury pain remains unclear. In this study, we aimed to determine the potential therapeutic mechanisms of pain. A mouse model of spinal cord contusion was established, and molecular expression in the anterior cingulate cortex (ACC) and periaqueductal gray (PAG) in the brain and animal behavior was observed after local injection of human umbilical cord mesenchymal stem cells (HU-MSCs) at the site of SCI. Method: Sixty-three female C57BL/6J mice were divided into four groups: a sham operation group (n = 15); a spinal injury group (SCI, n = 16); an SCI + HU-MSCs group (n = 16) and an SCI + PBS group (n = 16), in which the SCI site was injected with HU-MSCs/phosphate buffer. The BMS score was determined, and the von Frey test and Hargreaves test were used to assess behavior every week after surgery. Mice were sacrificed in the fourth week after operation, and samples were collected. The expression of CGRP, Substance P, C-Fos and KCC2 in the ACC and PAG were observed with immunohistochemistry. Chromic cyanine staining was used to observe transverse sections of the injured spinal cord. Result: In the ACC and PAG after SCI, the expression of CGRP, SP and C-Fos increased, and the expression of KCC2 decreased, whereas after HU-MSC injection, the expression of CGRP, SP and C-Fos decreased, and the expression of KCC2 increased. The SCI + HU-MSC group showed better exercise ability from 2 to 4 weeks after surgery than the SCI/SCI + PBS groups (P < 0.001). Local injection of HU-MSCs significantly improved the mechanical hyperalgesia caused by SCI in the fourth week after surgery (P < 0.0001), and sensation was significantly recovered 2 weeks after surgery (P < 0.0001); no improvement in thermal hypersensitivity was observed (P > 0.05). The HU-MSC group retained more white matter than the SCI/SCI + PBS groups (P < 0.0001). Conclusion: Local transplantation of HU-MSCs at the site of SCI partially relieves the neuropathic pain and promotes recovery of motor function. These findings suggest a feasible direction for the future treatment of SCI.

Heterojunction construction by a coordination bond between metal-organic frameworks and CdIn2S4 for improved photocatalytic performance.

Photocatalytic water splitting using a semiconductor is one of the most effective ways to obtain clean energy. However, a pure semiconductor exhibits a poor photocatalytic performance because of its harsh charge carrier recombination, limited light harvesting ability and deficiency of surface reactive sites. Herein, the hydrothermal method is employed to synthesize a new UiO-66-NH2/CdIn2S4 (NU66/CIS) heterojunction nanocomposite, constructed via a coordination bond between NU66 and CIS. Benefitting from the great specific surface area, the UiO-66-NH2 provides abundant reactive sites on its surface to boost the water reduction. Moreover, the amino groups in the UiO-66-NH2 are supplied as coordination sites to establish strong interactions between NU66 and CIS, thus forming the heterojunction with intimate connections. Therefore, the electrons produced by photoexcitation of CIS can be more effectively promoted to transfer to NU66, and then react with H+ in water to produce H2. Accordingly, the optimized 8% NU66/CIS heterojunction exhibits a considerable photocatalytic efficiency for water splitting, in which the H2 production rate is 7.8 times higher than that of bare CIS, and 3.5 times as high as that of the two materials combined by simple physical mixing. This research offers a creative and innovative idea for the construction of active MOF-based photocatalysts for H2 evolution.

Recent Advances in Biomaterials-Based Therapies for Alleviation and Regeneration of Traumatic Brain Injury.

Traumatic brain injury (TBI), a major public health problem accompanied with numerous complications, usually leads to serve disability and huge financial burden. The adverse and unfavorable pathological environment triggers a series of secondary injuries, resulting in serious loss of nerve function and huge obstacle of endogenous nerve regeneration. With the advances in adaptive tissue regeneration biomaterials, regulation of detrimental microenvironment to reduce the secondary injury and to promote the neurogenesis becomes possible. The adaptive biomaterials could respond and regulate biochemical, cellular, and physiological events in the secondary injury, including excitotoxicity, oxidative stress, and neuroinflammation, to rebuild circumstances suitable for regeneration. In this review, the development of pathology after TBI is discussed, followed by the introduction of adaptive biomaterials based on various pathological characteristics. The adaptive biomaterials carried with neurotrophic factors and stem cells for TBI treatment are then summarized. Finally, the current drawbacks and future perspective of biomaterials for TBI treatment are suggested.

Fault Early Warning Model for High-Speed Railway Train Based on Feature Contribution and Causal Inference.

The demands for model accuracy and computing efficiency in fault warning scenarios are increasing as high-speed railway train technology continues to advance. The black box model is difficult to interpret, making it impossible for this technology to be widely adopted in the railway industry, which has strict safety regulations. This paper proposes a fault early warning machine learning model based on feature contribution and causal inference. First, the contributions of the features are calculated through the Shapley additive explanations model. Then, causal relationships are discovered through causal inference models. Finally, data from causal and high-contribution time series are applied to the model. Ablation tests are conducted with the Naïve Bayes, Gradient Boosting Decision Tree, eXtreme Gradient Boosting, and other models in order to confirm the efficiency of the method based on early warning data regarding the on-site high-speed train traction equipment circuit board failure. The findings indicate that the strategy improves the evaluation markers, including the early warning accuracy, precision, recall, and F1 score, by an average of more than 10%. There is a 35% improvement in the computing efficiency, and the model can provide feature causal graph verification for expert product decision-making.

Label Noise Learning Method for Metallographic Image Recognition of Heat-Resistant Steel for Use in Pressure Equipment.

In metallographic examination, spherular pearlite gradation, an important step in a metallographic examination, is the main indicator used to assess the reliability of heat-resistant steel. Recognition of pearlite spheroidization via the manual way mainly depends on the subjective perceptions and experience of each inspector. Deep learning-based methods can eliminate the effects of the subjective factors that affect manual recognition. However, images with incorrect labels, known as noisy images, challenge successful application of image recognition of deep learning models to spherular pearlite gradation. A deep-learning-based label noise method for metallographic image recognition is thus proposed to solve this problem. We use a filtering process to pretreat the raw datasets and append a retraining process for deep learning models. The presented method was applied to image recognition for spherular pearlite gradation on a metallographic image dataset which contains 422 images. Meanwhile, three classic deep learning models were also used for image recognition, individually and coupled with the proposed method. Results showed that accuracy of image recognition by a deep learning model solely is lower than the one coupled with our method. Particularly, accuracy of ResNet18 was improved from 72.27% to 77.01%.

Haemaphysalis longicornis calreticulin is not an effective molecular tool for tick bite diagnosis and disruption of tick infestations.

BACKGROUND: Tick calreticulin (CRT) is a calcium-binding protein secreted into the host during blood feeding. It has been used as a biomarker of tick exposure and has potential as an anti-tick vaccine, but there is no information about these uses for Haemaphysalis longicornis CRT (HlCRT). We synthesized recombinant H. longicornis CRT (rHlCRT) and evaluated its potential for tick bite diagnosis and for disrupting tick infestations. METHODS: The responses of mice and rabbits exposed to H. longicornis ticks were measured with ELISA to determine the antibody level against rHlCRT. To evaluate the effects of rHlCRT-induced anti-tick immunity, engorgement weight, tick engorgement index (TEI), feeding duration, ecdysis rate, and egg weight per engorged tick were compared between ticks fed on immunized and normal mice. RESULTS: Mean anti-tick CRT antibody levels in sera collected from mice at 1 and 15 days after primary tick exposure were not significantly different from the mean antibody levels in negative control mice that were not bitten by ticks (all P values > 0.05). No significant anti-HlCRT IgG responses developed in mice after second exposure to tick bites compared with the level of anti-HlCRT antibody response in negative control mice (all P values > 0.25). For rabbits, no significant differences in the antibody levels were observed in animals before challenge infestation and after tick exposures, and in animals after two tick exposures (all P values > 0.10). There were no significant differences in the body weight of ticks fed on immunized and normal mice (all P values > 0.15). No significant differences in TEI were observed between ticks fed on immunized mice and normal control mice (all P values > 0.50). There were no significant differences in feeding duration for female ticks, and feeding duration and ecdysis rate for nymphs in the experimental and control groups (all P values > 0.10 for feeding duration and P value = 0.19 for ecdysis rate). We did not observe a significant difference in egg weight per tick in the rHlCRT-immunized and the control groups (P = 0.88). CONCLUSIONS: HlCRT in H. longicornis tick saliva proteins appears to be nonimmunogenic to mammalian hosts like mice and rabbits. Vaccination with rHlCRT did not generate effective immunity against parthenogenetic and bisexual H. longicornis nymphs or female ticks. These results indicate that HlCRT is not a suitable molecular candidate for H. longicornis tick bite diagnosis and not effective for the disruption of tick infestations.

Detection and phylogenetic analysis of tick-borne bacterial and protozoan pathogens in a forest province of eastern China.

Ticks, as obligate blood-sucking ectoparasites, feed on a broad range of vertebrates and transmit a great diversity of pathogenic microorganisms. Some tick-borne pathogens (TBPs) are endemic in China, whereas epidemiological studies are limited in Jiangxi, a forest province located in eastern China. Here, we have determined the positivity rates of TBPs in humans, rodents, dogs, goats and ticks, and performed the molecular characterization of TBPs in Jiangxi province. We found a high positivity rate of TBPs in the collected samples, demonstrating 23 (12.92%) samples positive for more than one TBPs. Of those, 11 (6.18%) samples were positive for Rickettsia spp., six (3.37%) Ehrlichia spp./Anaplasma spp., one (0.56%) Bartonella spp., two (1.12%) Borrelia spp., and five (2.81%) Babesia spp. The positivity rates of TBPs varied among ticks, animals, and humans as follow: goats (14/37, 37.84%), ticks (8/35, 22.86%), and dogs (1/11, 9.09%). Humans and rodents were negative for TBP presence. Phylogenetic analyses of these TBP sequences revealed the presence of Rickettsia japonica, Ehrlichia minasensis, and an unclassified Babesia spp. in goats, and Anaplasma phagocytophilum, Borrelia valaisiana, and an unclassified Bartonella spp. in ticks. Furthermore, R. japonica infection was exclusively found in goats with the positivity rate of 29.73%. Our study is the first report of R. japonica in goats around the world. These findings suggest high TBP positivity rates among goats, ticks, and dogs, and diverse TBPs in goats and ticks in the studied sites. Therefore, our results underscore the urgent need to assess TBP-tick-vertebrate-environment interactions and the risk of tick borne disease exposure in humans in the future.