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Objective: Despite extensive research on the link between pornography exposure and sexual aggression, inconsistent results have hindered consensus on the association. To help resolve inconsistencies and advance the field of knowledge, the present study conducted a latent profile analysis to identify common patterns of pornography exposure and to examine their associations with sexual aggression and its risk factors. Method: A total of 491 men in the United States completed assessments of six pornography exposure profile indicators (i.e., frequency of pornography exposure, duration of typical pornography exposure, and exposure to pictures, sex films, degrading films, and violent films) and six outcome variables (i.e., sexual aggression, rape myth acceptance, hostile masculinity, casual sex, psychopathy, and emotion regulation difficulties). Results: The analysis identified three profiles: "infrequent pornography viewers" (n = 113), "average pornography viewers" (n = 302), and "violent pornography viewers" (n = 76). Compared to the infrequent pornography viewers and average pornography viewers profiles, the violent pornography viewers profile had significantly higher means for each outcome variable (ps <.05). Significant differences between the infrequent pornography viewers and average pornography viewers profiles were found for casual sex and difficulties engaging in goal-directed behavior (ps <.05), but not the other outcome variables. Conclusions: Findings provided further insight into the association between pornography and sexual aggression in a way that cannot be observed using a variable-centered approach. [ABSTRACT FROM AUTHOR]

Coal and gas outbursts are anthropogenic hazards that can be divided into four stages: preparation, occurrence, development, and termination. Studying the influence of gas on coal damage and energy changes during the formation of outbursts is highly important for investigating the entire hazard. In this paper, laboratory experiments were performed on samples. The energy changes and failure mechanism of coal under different gas pressures were revealed, and a seepage model was established based on compressibility and adsorption to investigate gas-induced coal damage. The results demonstrated that gas pressure caused initial damage within the coal, resulting in nonlinear deformation and strength deterioration of the coal. Gas-induced damage affected the energy evolution mechanism of coal under loading, as pressure caused the premature release of energy at the tips of internal microcracks and reduced the ability to accumulate energy. These changes increased the proportion of dissipative energy under unstable conditions. The combined acoustic emission (AE) parameters—rising angle (RA) and average frequency (AF)—were used to study the fracture mode of gas-containing coal. As the gas pressure increased from 0 to 4 MPa, the RA–AF distribution pattern changed from tensile failure to tensile–shear composite failure, with the proportion of shear cracks increasing from 0.30% to 25.44%. As the complexity of the crack network increased, the randomness of crack propagation increased, and the fracture surface roughness parameters, arithmetic mean height S a , root mean square height S q , and maximum height S z increased by 90.33%, 94.02%, and 81.70%, respectively. These findings could contribute to a comprehensive understanding of the underlying mechanism of coal and gas outbursts and guide for predicting and preventing these hazards. [ABSTRACT FROM AUTHOR]

While participatory design approaches aim to include stakeholders in all design activities, in resource-limited situations, participation is challenging. Participatory designers often make decisions dealing with the tension between the agency of stakeholder participants and the project's viability. In designing health services, care professionals have limited availability, and patients, such as low-income older adults, have limitations such as lack of transportation and lower access to specialized communication technology or broadband. Yet, it is critical to find innovative ways to engage stakeholders in the design process for services and interventions that aim to improve their health and well-being. This article explores new ways to engage stakeholders in the participatory design process in resource-limited projects. We used a case study approach focused on the design experience of a project focused on social isolation and older adults to understand the complexity of real-world participatory design. While there are tradeoffs between project viability and stakeholders' agency, stakeholders' agency is possible in resource-limited projects. However, experts must adjust and balance influence in different activities to achieve meaningful participation of all stakeholders. [ABSTRACT FROM AUTHOR]

As underground excavations become deeper, violent rock failures associated with the sudden release of elastic energy become more prevalent, threatening the safety of workers and construction equipment. It is important to figure out the energy-related failure mechanisms of rocks. However, the energy evolution across the complete deformation of different types of rocks and the effect of high confinement on energy storage and release are not well understood in the literature. In this study, a series of cyclic triaxial compression tests were conducted for Class I and Class II rocks to investigate the confinement-dependent characteristics of energy evolution. The results showed that three types of energy evolution were identified as the rock behavior changed from brittle to ductile. The energy storage limit was linearly enhanced by confinement. The nonlinear increase in dissipated energy at peak stress with increasing confinement was suggested to indicate the start of the brittle–ductile transition. The post-peak fracturing process was characterized using the ratio of the local withdrawn elastic energy and fracture energy, and a novel energy-based index was proposed to quantify the failure intensity of the rock. This paper presents a complete investigation of the energy conversion characteristics of the rock, which may shed light on the failure mechanisms of violent rock failures in underground projects. [ABSTRACT FROM AUTHOR]

In recent years, the performance of infrared and visible image fusion has been dramatically improved by using deep learning techniques. However, the fusion results are still not satisfactory as the fused images frequently suffer from blurred details, unenhanced vital regions, and artifacts. To resolve these problems, we have developed a novel feature attention-guided perceptual generative adversarial network (FAPGAN) for fusing infrared and visible images. In FAPGAN, a feature attention module is proposed to incorporate with the generator aiming to produce a fused image that maintains the detailed information while highlighting the vital regions in the source images. Our feature attention module consists of spatial attention and pixel attention parts. The spatial attention aims to enhance the vital regions while the pixel attention aims to make the network focus on high frequency information to retain the detailed information. Furthermore, we introduce a perceptual loss combined with adversarial loss and content loss to optimize the generator. The perceptual loss is to make the fused image more similar to the source infrared image at the semantic level, which can not only make the fused image maintain the vital target and detailed information from the infrared image, but also remove the halo artifacts by reducing the discrepancy. Experimental results on public datasets demonstrate that our FAPGAN is superior to those of state-of-the-art approaches in both subjective visual effect and objective assessment. [ABSTRACT FROM AUTHOR]

To investigate the effect of liquid nitrogen on the granite failure process, the deterioration effect of liquid nitrogen on heated granite was investigated from experimental and theoretical perspectives. The mechanical properties of heated granite (25, 100, 200, 300, and 400 °C) after different cooling treatments (air cooling and liquid nitrogen cooling) were investigated by uniaxial compression tests. The damage evolution analysis was performed by a statistical damage constitutive model and the dissipation energy ratio was newly defined. The results show that there is an increase in the uniaxial compressive strength of heated granite before 200 °C, which is due to the competitive relationship between the thermal cracking and crack closure. Liquid nitrogen cooling can deteriorate the mechanical properties of heated granite in terms of strength and deformability. At 400 °C, the reduction rates of compressive strength and stiffness between air cooling and liquid nitrogen cooling reached 32.36% and 47.72%, respectively. Liquid nitrogen cooling induces greater initial thermal damage and, consequently, leads to a greater degree of total damage before the peak stress and makes rock easier to be damaged. At 400 °C, the total damage at the peak stress increased from 0.179 to 0.587 after the liquid nitrogen cooling. The difficulty of damage can be quantified by the dissipation energy ratio. In addition, the deterioration of liquid nitrogen on granite is positively related to temperature. This study confirmed the deterioration effect of liquid nitrogen and promoting effect of temperature, providing a theoretical approach to the degradation mechanism of liquid nitrogen. [ABSTRACT FROM AUTHOR]

Owing to its wide range of applications, 3D object detection has attracted increasing attention in computer vision tasks. Most existing 3D object detection methods are based on Lidar point cloud data. However, these methods have some limitations in localization consistency and classification confidence, due to the irregularity and sparsity of Light Detection and Ranging (LiDAR) point cloud data. Inspired by the complementary characteristics of Lidar and camera sensors, we propose a new end-to-end learnable framework named Point-Image Fusion Network (PIFNet) to integrate the LiDAR point cloud and camera images. To resolve the problem of inconsistency in the localization and classification, we designed an Encoder-Decoder Fusion (EDF) module to extract the image features effectively, while maintaining the fine-grained localization information of objects. Furthermore, a new effective fusion module is proposed to integrate the color and texture features from images and the depth information from the point cloud. This module can enhance the irregularity and sparsity problem of the point cloud features by capitalizing the fine-grained information from camera images. In PIFNet, each intermediate feature map is fed into the fusion module to be integrated with its corresponding point-wise features. Furthermore, point-wise features are used instead of voxel-wise features to reduce information loss. Extensive experiments using the KITTI dataset demonstrate the superiority of PIFNet over other state-of-the-art methods. Compared with several state-of-the-art methods, our approach outperformed by 1.97% in mean Average Precision (mAP) and by 2.86% in Average Precision (AP) for the hard cases on the KITTI 3D object detection benchmark. [ABSTRACT FROM AUTHOR]

Although many deep-learning-based methods have achieved considerable detection performance for pedestrians with high visibility, their overall performances are still far from satisfactory, especially when heavily occluded instances are included. In this research, we have developed a novel pedestrian detector using a deformable attention-guided network (DAGN). Considering that pedestrians may be deformed with occlusions or under diverse poses, we have designed a deformable convolution with an attention module (DCAM) to sample from non-rigid locations, and obtained the attention feature map by aggregating global context information. Furthermore, the loss function was optimized to get accurate detection bounding boxes, by adopting complete-IoU loss for regression, and the distance IoU-NMS was used to refine the predicted boxes. Finally, a preprocessing technique based on tone mapping was applied to cope with the low visibility cases due to poor illumination. Extensive evaluations were conducted on three popular traffic datasets. Our method could decrease the log-average miss rate ( M R − 2 ) by 12.44% and 7.8%, respectively, for the heavy occlusion and overall cases, when compared to the published state-of-the-art results of the Caltech pedestrian dataset. Of the CityPersons and EuroCity Persons datasets, our proposed method outperformed the current best results by about 5% in M R − 2 for the heavy occlusion cases. [ABSTRACT FROM AUTHOR]

Gametogenesis, the formation of gametes from gametocytes, an essential step for malaria parasite transmission, is targeted by transmission‐blocking drugs and vaccines. We identified a conserved protein (PBANKA_0305900) in Plasmodium berghei, which encodes a protein of 22 kDa (thus named Pb22) and is expressed in both asexual stages and gametocytes. Its homologues are present in all Plasmodium species and its closely related, Hepatocystis, but not in other apicomplexans. Pb22 protein was localised in the cytosols of schizonts, as well as male and female gametocytes. During gamete‐to‐ookinete development, Pb22 became localised on the plasma membranes of gametes and ookinetes. Compared to the wild‐type (WT) parasites, P. berghei with pb22 knockout (KO) showed a significant reduction in exflagellation (~89%) of male gametocytes and ookinete number (~97%) during in vitro ookinete culture. Mosquito feeding assays showed that ookinete and oocyst formation of the pb22‐KO line in mosquito midguts was almost completely abolished. These defects were rescued in parasites where pb22 was restored. Cross‐fertilisation experiments with parasite lines defective in either male or female gametes confirmed that the defects in the pb22‐KO line were restricted to the male gametes, whereas female gametes in the pb22‐KO line were fertile at the WT level. Detailed analysis of male gametogenesis showed that 30% of the male gametocytes in the pb22‐KO line failed to assemble the axonemes, whereas ~48.9% of the male gametocytes formed flagella but failed to egress from the host erythrocyte. To explore its transmission‐blocking potential, recombinant Pb22 (rPb22) was expressed and used to immunise mice. in vitro assays showed that the rPb22‐antisera significantly inhibited exflagellation by ~64.8% and ookinete formation by ~93.4%. Mosquitoes after feeding on rPb22‐immunised mice also showed significant decreases in infection prevalence (83.3–93.3%) and oocyst density (93.5–99.6%). Further studies of the Pb22 orthologues in human malaria parasites are warranted. [ABSTRACT FROM AUTHOR]

Quiescin sulfhydryl oxidase (QSOX), present in a wide variety of eukaryotic species, catalyzes the insertion of disulfide bonds into unfolded, reduced proteins. Here we characterized the QSOX protein from the rodent malaria parasite Plasmodium berghei (PbQSOX), which is conserved in all sequenced malaria parasite species. The PbQSOX protein was not expressed in asexual erythrocytic stages, but was most abundantly expressed in ookinetes. Indirect immunofluorescence assays revealed PbQSOX was not only localized in cytoplasm of gametocytes, gametes and ookinetes, but also expressed on the surface of gametes and ookinetes. Western blot identified extracellular presence of PbQSOX in the culture medium of ookinetes suggestive of secretion. Pbqsox deletion (Δ pbqsox) did not affect asexual intraerythrocytic development, but reduced exflagellation of male gametocytes as well as formation and maturation of ookinetes. Pbqsox deletion also led to a significant increase in the reduced thiol groups of ookinete surface proteins, suggesting that it may play a role in maintaining the integrity of disulfide bonds of surface proteins, which might be needed for ookinete development. Mosquitoes that fed on Δ pbqsox -infected mice showed a significant reduction in ookinete and oocyst numbers compared to those fed on wild-type parasite-infected mice. Further, both polyclonal mouse antisera and a monoclonal antibody against the recombinant PbQSOX exhibited substantial transmission-blocking activities in in vitro and mosquito feeding assays, suggesting QSOX is a potential target for blocking parasite transmission. [ABSTRACT FROM AUTHOR]

Paraneoplastic neurological syndromes (PNS) are rare disorders affecting any part of the central, peripheral or autonomic nervous system that occur in association with cancer. Among cancer patients, less than 1% overall develop PNS. Anti‐SOX1 antibodies' positive paraneoplastic neurological disorders are rare and are usually associated with small cell lung cancer (SCLC). Here, we report a case of a 61‐year‐old male patient who presented with an unusual anti‐SOX1 positive PNS. The right tibialis anterior showed noticeable low‐amplitude motor unit potentials and high amplitude motor potentials in electrodiagnostic study, suggesting the presence of Lambert‐Eaton myasthenic syndrome (LEMS). Typical MRI and PET‐CT found a hyperintense lesion with contrast enhancement in the thorax in front of 5–6 centrum of vertebrae, and thoracoscopic biopsy revealed pathological findings for SCLC. The patient underwent several lines of chemotherapy and radiotherapy and survived for 15 months after the diagnosis of SCLC. [ABSTRACT FROM AUTHOR]

Trapped lung is defined by the lung's inability to expand and fill the thoracic cavity because of a restricting “peel” caused by benign or malignant pleural disease. However, trapped lung secondary to pneumothorax is rarely reported. We present a case of trapped lung caused by a pneumothorax that occurred some 14 years before the patient presented to our hospital with a complaint of incapacitating dyspnea. Computed tomography (CT) scans revealed trapping of the right lung with abnormal thickening of the visceral pleura. In view of the patient's history of pneumothorax, we concluded that his dyspnea was attributable mainly to the trapping of his lung by the earlier pneumothorax. We therefore scheduled thoracoscopic decortication, which was successfully completed. The patient's recovery after the operation was uneventful, and seven weeks after surgery the right lung had re‐expanded well. [ABSTRACT FROM AUTHOR]

Most of the three-dimensional (3D) object detection methods based on LiDAR point cloud data achieve relatively high performance in general cases. However, when the LiDAR points have noise or some corruptions, the detection performance can be severely affected. We propose a 3D object detection method that combines point cloud information with two-dimensional (2D) semantic segmentation information to enhance the feature representation for difficult cases, such as sparse, noisy, and partially absent data. Motivated by the Pointpainting techniques, we designed an early-stage fusion method based on a Voxel region-based convolutional neural network (R-CNN) architecture. The 2D semantic segmentation scores obtained by the Pointpainting techniques are appended to the raw point cloud data. The voxel-based features and 2D semantic information improve the performance in detecting instances when the point cloud is corrupted. In addition, we also designed a multiscale hierarchical region of interest pooling strategy that reduced the computational cost of Voxel R-CNN by at least 43%. Our method shows competitive results with the state-of-the-art methods on the standard KITTI dataset. In addition, three corrupted KITTI datasets, KITTI sparse (KITTI-S), KITTI jittering (KITTI-J), and KITTI dropout (KITTI-D), were used for robustness testing. With the noisy LiDAR points, our proposed point painted Voxel R-CNN achieved superior detection performance over that of the baseline Voxel R-CNN for the moderate case, with a notable improvement of 11.13% in average precision (AP) on the 3D object detection and 14.3% in AP on the bird's eye view object detection. [ABSTRACT FROM AUTHOR]

A study on thermogravimetric analyses, surface photovoltage (SPV), electron paramagnetic resonance and electrochemical properties comparing a porphyrin dimer with that of corresponding monomer was presented. The SPV intensity is weaker than that corresponding monomer, and with field-induced surface photovoltage spectroscopy (FISPS) reveal that all the compounds are p-type semiconductors. The spectral bands of all the porphyrins corresponded to π → π* transitions. Electrons (or holes) can be trapped on the porphyrins by applying both light and negative (or positive) electric field. The electrochemistry and EPR of the porphyrins show clearly that a π-π interaction existed between the two macrocycles of the dimer. [ABSTRACT FROM AUTHOR]

In order to search for novel luminescent and EPR oximetry materials, a series of porphyrins and metalloporphyrins with different peripheral substitutes and central transition metal ions were synthesized and their UV–vis, fluorescence and EPR spectra were studied. It was found that variations in the peripheral substituents imparted no change to the UV–vis spectra in the case of metal-free porphyrins. However, differences in the central transition metal ions resulted in changes in the energy of electron transitions which caused changes in UV–vis spectra. Variations in the peripheral substituents and the central metal ions influenced both the fluorescence and EPR spectra. [Copyright &y& Elsevier]

With the speeding tendency of aging society, the population experienced dysphagia is increasing quickly. Desirable dysphagic diets should be safe, visually appealing and nutritious. 3D printing allows for creation of personalized nutritious foods with regular-like appearance. Shiitake mushroom, rich in protein and bioactive compounds, is suitable for elderly, but its hard texture was not friendly to the elderly with dysphagia. This study investigated the feasibility of production of dysphagic product using shiitake mushroom by 3D printing with various gums addition, including arabic gum (AG), xanthan gum (XG) and k-carrageenan gum (KG) at concentrations of 0.3%, 0.6% and 0.9% (w/w). Data suggested that XG and KG incorporation significantly increased inks' mechanical strength by decreasing water mobility and promoting the formation of hydrogen bond, enabling 3D printed objects with great self-supporting capacity. The XG containing and KG-0.3% samples were categorized into level 5—minced and moist dysphagia diet within international dysphagia diet standardization initiative (IDDSI) framework. AG addition decreased mechanical strength and viscosity, hardness and self-supporting capacity of 3D printed constructions. AG-0.3% and AG-0.6% samples could not be classified as dysphagia diets based on IDDSI tests. This study provides useful information for dysphagia diet development with appealing appearance by 3D printing. [ABSTRACT FROM AUTHOR]

Sulfated polysaccharides from sea cucumbers possess distinct chemical structure and various biological activities. Herein, three types of polysaccharides were isolated and purified from Pattalus mollis, and their structures and bioactivities were analyzed. The fucosylated glycosaminoglycan (PmFG) had a CS-like backbone composed of the repeating units of {-4-d-GlcA-β-1,3-d-GalNAc4S6S-β-1-}, and branches of a sulfated α-l-Fuc (including Fuc2S4S, Fuc3S4S and Fuc4S with a molar ratio of 2:2.5:1) linked to O-3 of each d-GlcA. The fucan sulfate (PmFS) had a backbone consisting of a repetitively linked unit {-4-l-Fuc2S-α-1-}, and interestingly, every trisaccharide unit in its backbone was branched with a sulfated α-l-Fuc (Fuc4S or Fuc3S with a molar ratio of 4:1). Apart from the sulfated polysaccharides, two neutral glycans (PmNG-1 & -2) differing in molecular weight were also obtained and their structures were similar to animal glycogen. Anticoagulant assays indicated that PmFG and PmFS possessed strong APTT prolonging and intrinsic factor Xase inhibition activities, and the sulfated α-l-Fuc branches might contribute to the anticoagulant and anti-FXase activities of both PmFG and PmFS. [ABSTRACT FROM AUTHOR]

Apostichopus japonicus is one of the most economically important species in sea cucumber aquaculture in China. Fucosylated glycosaminoglycan from A. japonicus (AjFG) has shown multiple pharmacological activities. However, results from studies on the structure of AjFG are still controversial. In this study, the deaminative depolymerization method that is glycosidic bond-selective was used to prepare the depolymerized products from AjFG (dAjFG), and then a series of purified oligosaccharide fragments such as tri-, hexa-, nona-, and dodecasaccharides were obtained from dAjFG by gel permeation chromatography. The 1D/2D NMR and ESI-MS spectrometry analyses showed that these oligosaccharides had the structural formula of l-FucS-α1,3-d-GlcA-β1,3-{d-GalNAc4S6S-β1,4-[l-FucS-α1,3-]d-GlcA-β1,3-}n-d-anTal-diol4S6S (n = 0, 1, 2, 3; FucS represents Fuc2S4S, Fuc3S4S, or Fuc4S). Thus, the unambiguous structure of native AjFG can be rationally deduced: it had the backbone of {-4-d-GlcA-β1,3-d-GalNAc4S6S-β1-}n, which is similar to chondroitin sulfate E, and each d-GlcA residue in the backbone was branched with a l-FucS monosaccharide at O-3. Bioactivity assays confirmed that dAjFG and nonasaccharides and dodecasaccharides from AjFG had potent anticoagulant activity by intrinsic FXase inhibition while avoiding side effects such as FXII activation and platelet aggregation. [ABSTRACT FROM AUTHOR]

• We generated transgenic P. berghei parasites expressing Pv22. • We used the transgenic parasites to evaluate Pv22′s transmission-blocking potential. • Clinical P. vivax isolates were used in membrane feeding. • Antibodies against rPv22 significantly reduced the oocyst density in mosquitoes. • Feeding assay results disfavor Pv22 as a promising TBV candidate. Antigens expressed during the sexual development of malaria parasites are transmission-blocking vaccine (TBV) targets. Pb22, a protein expressed and localized to the plasma membrane of gametes and ookinetes in Plasmodium berghei , is an excellent TBV candidate. Here, we evaluated the TB potential of the Plasmodium vivax ortholog Pv22 using a transgenic P. berghei parasite line and P. vivax clinical isolates. The full-length recombinant Pv22 (rPv22) protein was produced and used to immunize mice and rabbits to obtain antibodies. We generated a transgenic P. berghei line (TrPv22Pb) by inserting the pv22 gene into the pb22 locus and showed that Pv22 expression completely rescued the defects in male gametogenesis of the pb22 deletion parasite. Since Pv22 in the transgenic parasite showed similar expression and localization patterns to Pb22, we used the TrPv22Pb parasite as a surrogate to evaluate the TB potential of Pv22. In mosquito feeding assays, mosquitoes feeding on rPv22-immunized mice infected with TrPv22Pb parasites showed a 49.3–53.3 % reduction in the oocyst density compared to the control group. In vitro assays showed that the rPv22 immune sera significantly inhibited exflagellation and ookinete formation of the TrPv22Pb parasites. In a direct membrane feeding assay using three clinical P. vivax isolates, the rabbit anti-rPv22 antibodies also significantly decreased the oocyst density by 53.7, 30.2, and 26.2 %, respectively. This study demonstrated the feasibility of using transgenic P. berghei parasites expressing P. vivax antigens as a potential tool to evaluate TBV candidates. However, the much weaker TB activity of Pv22 obtained from two complementary assays suggest that Pv22 may not be a promising TBV candidate for P. vivax. [ABSTRACT FROM AUTHOR]

Fucan sulfates from echinoderm possess characteristic structures and various biological activities. Herein, comprehensive methods including enzymolysis, ion-exchange chromatography and size exclusion chromatography lead to the purification of five fucan sulfates (FSI, FSII, FSIII, FSIV, FSV) from the sea cucumber Pattalus mollis. Chemical composition analysis showed that they were all composed of l -fucose. Their sulfate content was determined by a conductimetric method. The molecular weight (Mw) of FSI, FSII, FSIII, FSIV and FSV were measured as 238.3 kDa, 81.0 kDa, 82.0 kDa, 23.2 kDa and 6.12 kDa, respectively. Detailed NMR spectroscopic analysis revealed that the structural sequence of FSI and FSII was →3)- l -Fuc S -α(1→, where Fuc S were Fuc 2S4S (10%), Fuc 2S (44%), Fuc 0S (10%), Fuc 4S (36%), that of FSIII was →4)- l -Fuc 2S -(α1 → 4)- l -Fuc 2S -(α1 → 4)- l -Fuc 0S/3S -(α1→, where Fuc 0S and Fuc 3S were in equal molar, and that FSIV was →4)- l -Fuc 2S3S -(α1 → 4)- l -Fuc 2S3S -(α1 → 4)- l -Fuc 2S -(α1→4)- l -Fuc 2S -(α1 → 4)- l -Fuc 2S -(α1 → 4)- l -Fuc 2S -(α1 →. This is the first report that such a diversity of fucan sulfates were obtained from the same sea cucumber species. Biological activity showed that FSI, FSII, FSIII and FSIV exhibited potent anticoagulant by prolonging the APTT. Among them, FSII, FSIII and FSIV showed the similar potency, while FSI owned the strongest. Structure-activity relationships analysis showed that molecular weight and sulfation degree should be the crucial factors for the activity. • Five fucan sulfates were purified from sea cucumber Pattalus mollis. • The physicochemical properties of four fucan sulfates were characterized. • Structural unit of FSI and FSIII was →3)- l -Fuc S -α(1→ and →4)- l -Fuc 2S -(α1→4)- l -Fuc 2S -(α1→4)- l -Fuc 0S/3S -(α1→, respectively. • FSIV was composed of an α1,4-linked hexafucose repeating unit. • FSI exhibit strong inhibition of the intrinsic coagulation pathway. [ABSTRACT FROM AUTHOR]

Background: Transmission-blocking vaccines (TBVs) can effectively prevent the community's spread of malaria by targeting the antigens of mosquito sexual stage parasites. At present, only a few candidate antigens have demonstrated transmission-blocking activity (TBA) potential in P. vivax . Quiescin-sulfhydryl oxidase (QSOX) is a sexual stage protein in the rodent malaria parasite Plasmodium berghei and is associated with a critical role in protein folding by introducing disulfides into unfolded reduced proteins. Here, we reported the immunogenicity and transmission-blocking potency of the PvQSOX in P. vivax ., Methods and Findings: The full-length recombinant PvQSOX protein (rPvQSOX) was expressed in the Escherichia coli expression system. The anti-rPvQSOX antibodies were generated following immunization with the rPvQSOX in rabbits. A parasite integration of the pvqsox gene into the P. berghei pbqsox gene knockout genome was developed to express full-length PvQSOX protein in P. berghei (Pv-Tr-PbQSOX). In western blot, the anti-rPvQSOX antibodies recognized the native PvQSOX protein expressed in transgenic P. berghei gametocyte and ookinete. In indirect immunofluorescence assays, the fluorescence signal was detected in the sexual stages, including gametocyte, gamete, zygote, and ookinete. Anti-rPvQSOX IgGs obviously inhibited the ookinetes and oocysts development both in vivo and in vitro using transgenic parasites. Direct membrane feeding assays of anti-rPvQSOX antibodies were conducted using four field P. vivax isolates (named isolates #1-4) in Thailand. Oocyst density in mosquitoes was significantly reduced by 32.00, 85.96, 43.52, and 66.03% with rabbit anti-rPvQSOX antibodies, respectively. The anti-rPvQSOX antibodies also showed a modest reduction of infection prevalence by 15, 15, 20, and 22.22%, respectively, as compared to the control, while the effect was insignificant. The variation in the DMFA results may be unrelated to the genetic polymorphisms. Compared to the P.vivax Salvador (Sal) I strain sequences, the pvqsox in isolate #1 showed no amino acid substitution, whereas isolates #2, #3, and #4 all had the M361I substitution., Conclusions: Our results suggest that PvQSOX could serve as a potential P. vivax TBVs candidate, which warrants further evaluation and optimization., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Zheng, Cheng, Liu, Yu, Zhao, Yang, Thongpoon, Roobsoong, Sattabongkot, Luo, Cui and Cao.)

Transmission-blocking vaccines (TBVs) interrupting malaria transmission are an integrated tool for malaria eradication. We characterized a sexual-stage-specific gene (PBANKA&#95;060330) from Plasmodium berghei and studied its potential for use as a TBV. This gene, referred to as pbg37 , encodes a protein of 37 kDa with a signal peptide and multiple transmembrane domains and is preferentially expressed in gametocytes. A recombinant Pbg37 (rPbg37) protein targeting the N-terminal 63 amino acids (amino acids 26 to 88) expressed in bacteria elicited strong antibody responses in mice. Western blotting demonstrated Pbg37 expression in gametocytes, zygotes, and, to a lesser extent, ookinetes and its predominant association with the membranes of gametocytes. Indirect immunofluorescence assay showed an abundant surface localization of Pbg37 on gametes and zygotes but reduced amounts on retorts and ookinetes. Knockout of pbg37 (Δ pbg37 ) led to a considerable reduction in gametocytemia, which translated into a ~92.1% decrease in the oocyst number in mosquitoes. Deletion of pbg37 had a more substantial influence on the development and maturation of microgametocytes. As a result, the Δ pbg37 lines exhibited a higher female/male gametocyte ratio, fewer mature male gametocytes, and defects in the exflagellation of mature microgametocytes. To test the transmission-blocking potential of Pbg37, an in vitro ookinete assay showed that the major inhibitory effects of anti-Pbg37 antiserum were on the exflagellation and fertilization processes. Direct feeding of mosquitoes on mice immunized with rPbg37 or a control protein showed that rPbg37-immunized and P. berghei -infected mice had a significant reduction (49.1%) in oocyst density compared to the controls. The conservation of this gene in Plasmodium warrants further investigations in human malaria parasites., (Copyright © 2018 American Society for Microbiology.)

Background: A vaccine that targets multiple developmental stages of malaria parasites would be an effective tool for malaria control and elimination., Methods: A conserved gene in Plasmodium, the Plasmodium berghei gene (PBANKA&#95;020570) encoding a 51 kDa protein (pb51 gene), was identified through search of the PlasmoDB database using a combination of expression and protein localization criteria. A partial domain of the Pb51 protein was expressed in a prokaryotic expression system (rPb51) and used for immunization in mice. The protein expression profile and localization were studied by Western blot and indirect immunofluorescence assay (IFA), respectively. The inhibitory effect of the anti-rPb51 antibodies on parasite proliferation was evaluated in erythrocytes in vivo. The transmission-blocking activity of the immune sera was determined by in vitro ookinete conversion assay and by direct mosquito feeding assay (DFA)., Results: The rPb51 elicited specific antibodies in mice. Western blot confirmed Pb51 expression in schizonts, gametocytes and ookinetes. IFA showed localization of Pb51 on the outer membranes of schizonts, gametocytes, zygotes, retorts, ookinetes and sporozoites of P. berghei. Mice immunized with the rPb51 protein significantly reduced parasite proliferation and gametocyte conversion in vivo. Moreover, the rPb51 antisera also significantly reduced the in vitro ookinete conversion when added into the ookinete culture medium. In DFA, mice immunized with the rPb51 reduced the prevalence of mosquito infection by 21.3% and oocyst density by 54.8%., Conclusions: In P. berghei, P51 was expressed in both asexual erythrocytic and sexual stages and localized on the surface of these stages with the exception of the ring stage. The anti-rPb51 antibodies inhibited both P. berghei proliferation in mice and transmission of the parasite to mosquitoes.

Background: Plasmodium ookinete surface proteins as post-fertilization target antigens are potential malaria transmission-blocking vaccine (TBV) candidates. Putative secreted ookinete protein 25 (PSOP25) is a highly conserved ookinete surface protein, and has been shown to be a promising novel TBV target. Here, we further investigated the TBV activities of the full-length recombinant PSOP25 (rPSOP25) protein in Plasmodium berghei, and characterized the potential functions of PSOP25 during the P. berghei life-cycle., Methods: We expressed the full-length P. berghei PSOP25 protein in a prokaryotic expression system, and developed polyclonal mouse antisera and a monoclonal antibody (mAb) against the recombinant protein. Indirect immunofluorescence assay (IFA) and Western blot were used to test the specificity of antibodies. The transmission-blocking (TB) activities of antibodies were evaluated by the in vitro ookinete conversion assay and by direct mosquito feeding assay (DFA). Finally, the function of PSOP25 during Plasmodium development was studied by deleting the psop25 gene., Results: Both polyclonal mouse antisera and anti-rPSOP25 mAb recognized the PSOP25 proteins in the parasites, and IFA showed the preferential expression of PSOP25 on the surface of zygotes, retorts and mature ookinetes. In vitro, these antibodies significantly inhibited ookinetes formation in an antibody concentration-dependent manner. In DFA, mice immunized with the rPSOP25 and those receiving passive transfer of the anti-rPSOP25 mAb reduced the prevalence of mosquito infection by 31.2 and 26.1%, and oocyst density by 66.3 and 63.3%, respectively. Genetic knockout of the psop25 gene did not have a detectable impact on the asexual growth of P. berghei, but significantly affected the maturation of ookinetes and the formation of midgut oocysts., Conclusions: The full-length rPSOP25 could elicit strong antibody response in mice. Polyclonal and monoclonal antibodies against PSOP25 could effectively block the formation of ookinetes in vitro and transmission of the parasites to mosquitoes. Genetic manipulation study indicated that PSOP25 is required for ookinete maturation in P. berghei. These results support further testing of the PSOP25 orthologs in human malaria parasites as promising TBV candidates.

Background: Transmission-blocking vaccines (TBVs) are a promising strategy for malaria control and elimination. However, candidate TBV antigens are currently limited, highlighting the urgency of identifying new antigens for TBV development., Methods: Using a combination of bioinformatic analysis and functional studies in the rodent malaria model Plasmodium berghei, we identified a conserved Plasmodium protein PbPH (PBANKA&#95;041720) containing a pleckstrin homology (PH) domain. The expression of PbPH was detected by Western blot and indirect immunofluorescence assay (IFA). The function of PbPH was tested by genetic knockout. The TB activity was confirmed by in vitro ookinete conversion assay and mosquito feeding., Results: PbPH was detected in Western blot as highly expressed in sexual stages (gametocytes and ookinetes). IFA revealed localizations of PbPH on the surface of gametes, zygotes, and ookinetes. Deletion of the pbph gene did not affect asexual growth, but significantly reduced the formation of gametocytes, ookinetes, and oocysts, indicating that PbPH protein is required for parasite sexual development. Recombinant PbPH expressed and purified from bacteria elicited strong antibody responses in mice and the antibodies significantly inhibited exflagellation of male gametocytes and formation of ookinetes in a concentration-dependent manner. Mosquito feeding experiments confirmed that mosquitoes fed on mice immunized with PbPH had 13 % reduction in the prevalence of infection and almost 48 % reduction in oocyst density., Conclusions: Pbph is a highly conserved Plasmodium gene and is required for parasite sexual development. PbPH protein is expressed on the surface of gametes and ookinetes. Immunization of mice against the recombinant PbPH protein induced strong antibody responses that effectively reduced the formation of male gametes and ookinetes in vitro and blocked transmission of the parasites to mosquitoes. These results highlight PbPH as a potential TBV candidate that is worth future investigations in human malaria parasites.

Background: The male gamete fertilization factor P48/45 in malaria parasites is a prime transmission-blocking vaccine (TBV) candidate. Efforts to develop antimalarial vaccines are often thwarted by genetic diversity of the target antigens. Here we evaluated the genetic diversity of Pvs48/45 gene in global Plasmodium vivax populations., Methods: We determined 200 Pvs48/45 sequences collected from temperate and subtropical parasite populations in China. Population genetic and evolutionary analyses were performed to determine the levels of genetic diversity, potential signature of selection, and population differentiation., Results: Analysis of the Pvs48/45 sequences from 200 P. vivax parasites collected in a temperate and a tropical region revealed a low level of genetic diversity (π = 0.0012) with 14 single nucleotide polymorphisms, of which 11 were nonsynonymous. Analysis of 344 Pvs48/45 sequences from nine worldwide P. vivax populations detected a total of 38 haplotypes, of which 13 haplotypes were present only once. Multiple tests for selection confirmed a signature of positive selection on Pvs48/45 with selection skewed to the second cysteine domain. Haplotype network analysis and Wright's fixation index showed large geographical differentiation with the presence of continent-or region-specific mutations in this gene., Conclusions: Pvs48/45 displays low levels of genetic diversity with the presence of region-specific mutations. Some of the mutations may be potential epitope targets based on their positions in the predicted structure, highlighting the need for future evaluation of these mutations in designing Pvs48/45-based TBV.