With the deepening reform of ideological and political education, Medical Parasitology teaching needs to update the teaching concept, change the teaching ideas, as well as keep trying to combine ideological and political education with the curriculum content closely. In addition to teaching students' basic knowledge and practical skills, teachers are needed to cultivate their moral literacy and political awareness through course teaching, so as to provide the basis for students' subsequent adaptations to social environments and jobs. Currently, the study of ideological and political education in Medical Parasitology teaching is still in the exploratory stage. Therefore, colleges and universities need to carry out effective construction of ideological and political education in Medical Parasitology teaching, in order to achieve good teaching outcomes and provide insights into ideological and political education in teaching.

LIM homeodomain transcription factor 1‐alpha (LMX1a) is a neuronal lineage‐specific transcription activator that plays an essential role during the development of midbrain dopaminergic (mDA) neurons. LMX1a induces the expression of multiple key genes, which ultimately determine the morphology, physiology, and functional identity of mDA neurons. This function of LMX1a is dependent on its homeobox domain. Here, we determined the structures of the LMX1a homeobox domain in complex with the promoter sequences of the Wnt family member 1 (WNT1) or paired like homeodomain 3 (Pitx3) gene, respectively. The complex structures revealed that the LMX1a homeobox domain employed its α3 helix and an N‐terminal loop to achieve specific target recognition. The N‐terminal loop (loop1) interacted with the minor groove of the double‐stranded DNA (dsDNA), whereas the third α‐helix (α3) was tightly packed into the major groove of the dsDNA. Structure‐based mutations in the α3 helix of the homeobox domain significantly reduced the binding affinity of LMX1a to dsDNA. Moreover, we identified a nonsyndromic hearing loss (NSHL)‐related mutation, R199, which yielded a more flexible loop and disturbed the recognition in the minor groove of dsDNA, consistent with the molecular dynamics (MD) simulations. Furthermore, overexpression of Lmx1a promoted the differentiation of SH‐SY5Y cells and upregulated the transcription of WNT1 and PITX3 genes. Hence, our work provides a detailed elucidation of the specific recognition between the LMX1a homeobox domain and its specific dsDNA targets, which represents valuable information for future investigations of the functional pathways that are controlled by LMX1a during mDA neuron development.

Background The excretory/secretory (ES) antigen of Trichinella spiralis muscle larvae (ML) is currently the most widely used diagnostic antigen to detect T. spiralis infection. However, this antigen has certain drawbacks, such as a complicated ES antigen preparation process and lower sensitivity during the early phase of infection. The aim of this study was to investigate the features of a novel T. spiralis trypsin (TsTryp) and evaluate its potential diagnostic value for trichinellosis. Methods The TsTryp gene was cloned and recombinant TsTryp (rTsTryp) expressed. Western blotting and an enzyme-linked immunosorbent assay (ELISA) were performed to confirm the antigenicity of rTsTryp. The expression pattern and distribution signature of TsTryp at various life-cycle stages of T. spiralis were analyzed by quantitative PCR, western blotting and the immunofluorescence test. An ELISA with rTsTryp and ML ES antigens was used to detect immunoglobulins G and M (IgG, IgM) in serum samples of infected mice, swine and humans. The seropositive results were further confirmed by western blot with rTsTryp and ML ES antigens. Results TsTryp expression was observed in diverse T. spiralis life-cycle phases , with particularly high expression in the early developmental phase (intestinal infectious larvae and adults), with distribution observed mainly at the nematode outer cuticle and stichosome. rTsTryp was identified by T. spiralis -infected mouse sera and anti-rTsTryp sera. Natural TsTryp protease was detected in somatic soluble and ES antigens of the nematode. In mice infected with 200 T. spiralis ML, serum-specific IgG was first detected by rTsTryp-ELISA at 8 days post-infection (dpi), reaching 100% positivity at 12 dpi, and first detected by ES-ELISA at 10 dpi, reaching 100% positivity at 14 dpi. Specific IgG was detected by rTsTryp 2 days earlier than by ES antigens. When specific IgG was determined in serum samples from trichinellosis patients, the sensitivity of rTsTryp-ELISA and ES antigens-ELISA was 98.1% (51/52 samples) and 94.2% (49/52 samples), respectively ( P = 0.308), but the specificity of rTsTryp was significantly higher than that of ES antigens (98.7% vs. 95.4%; P = 0.030). Additionally, rTsTryp conferred a lower cross-reaction, with only three serum samples in total testing positive from 11 clonorchiasis, 20 cysticercosis and 24 echinococcosis patients (1 sample from each patient group). Conclusions TsTryp was shown to be an early and highly expressed antigen at intestinal T. spiralis stages, indicating that rTsTryp represents a valuable diagnostic antigen for the serodiagnosis of early Trichinella infection. Graphical Abstract

An impedimetric sensing strategy was developed for sensitively determining diethylstilbestrol (DES) based on a platform of porphyrin-containing covalent-organic framework (p-COF). The p-COF was synthesized using 5,10,15,20-tetra (4-aminophenyl) porphyrin (TAPP) and 1,3,6,8-tetrakis(4-formylphenyl) pyrene (TFPy) as building blocks via condensation reaction, for which p-COF was named as TAPP-TFPy-COF. Considering the large specific surface area (302.9 m2 g−1), high porosity, rich nitrogen functionality, superior electrochemical activity, and strong bioaffinity toward DNA strands, the TAPP-TFPy-COF-based platform exhibited enhanced, non-label, and amplified electrochemical signal, large number of immobilized DES-targeted aptamer strands, and fast-response toward the analyte. Electrochemical results reveal that the TAPP-TFPy-COF-based aptasensor promoted the sensing performance for the detection of DES, resulting in an extremely low limit of detection of 0.42 fg mL−1 within a DES concentration ranging from 1 fg mL−1 to 0.1 pg mL−1, which was substantially lower than those of most reported DES sensors. Furthermore, the TAPP-TFPy-COF-based aptasensor possessed outperformed stability, high selectivity, ascendant reproducibility, and acceptable applicability in diverse environments. The recovery values for DES detection in milk, tap water, and frozen shrimp were in the range 91.80–118.50% with low relative standard deviation of 0.11–4.26%. This work provides a new sensing electrochemical approach based on COF network for DES detection and shows a deep insight into the construction of COF-based biosensors, which can be extended to be used for other target compounds.

The plerocercoid larvae of the tapeworm Spirometra erinaceieuropaei can parasitize humans and animals and cause serious parasitic zoonosis. However, our knowledge of the developmental process of S. erinaceieuropaei is still inadequate. To better characterize differential and specific genes and pathways associated with parasite development, a comparative transcriptomic analysis of the plerocercoid stage and the adult stage was performed using RNA-seq and de novo analysis. Approximately 13,659 differentially expressed genes (DEGs) were identified in plerocercoids versus adults, of which 6455 DEGs were upregulated and 7204 were downregulated. DEGs involved in parasite immunoevasion were more active in plerocercoid larvae than in adults, while DEGs associated with metabolic activity were upregulated in adults. Gene Ontology (GO) and Kyoto Encyclopedia of Genes (KEGG) analyses revealed that most DEGs involved in protein phosphorylation/dephosphorylation and the Wnt signalling pathway were much more active in plerocercoid larvae. The molecular functions of upregulated unigenes in adults were mainly enriched for metabolic activities. qPCR validated that the expression levels of 10 selected DEGs were consistent with those in RNA-seq, confirming the accuracy of the RNA-seq results. Our results contributed to increasing the knowledge on the S. erinaceieuropaei gene repertoire and expression profile and also provide valuable resources for functional studies on the molecular mechanisms of S. erinaceieuropaei.

Thank you for your further exploration on our manuscript. Our opinions on the raised speculations were outlined below.

根据当前水稻品质育种和栽培的现状,对水稻品质进行了新的诠释.论述了加工品质和外观品质是基础、安全食用品质是前提、食味品质是关键、营养品质是根本的稻米品质关系,提出了今后水稻品质育种和优质化栽培的主攻方向,为全面提升稻米品质及其在国内外市场上的竞争力,满足人们日益增长的饮食文化需要提供理论指导.

以津川1号和津原E28为材料,采用自来水和纯净水煮饭,通过米饭感官评价和质地测定,明确水质对其食味的影响,同时研究这种影响是否与煮饭时的加水量和浸泡时间有关.结果表明,随加水量的增加,米饭外观、饭香、味道和综合评价感官得分先增大后减小,米水质量比为1:1.50时上述指标得分最高,食味最好;米水质量比在1:1.25～1.50范围内,用纯净水蒸煮的米饭的味道和粘度感官得分要高于用自来水蒸煮的米饭.随煮饭加水量的增加,米饭的硬度下降、粘度增加,与感官评价结果一致.随大米浸泡时间延长,米饭外观、味道、粘度和综合评价感官得分先增加后减小,浸泡1.0 h,上述指标得分最高,食味最好.浸泡时间延长会降低米饭的饭香.在浸泡时间15.0 h内,与用自来水浸泡后蒸煮相比,用纯净水浸泡后蒸煮的米饭食味感官综合评价更高.综上,对津川1号和津原E28而言,米水质量比为1:1.50,浸泡1.0 h,使用纯净水煮饭可以获得更好的食味.

试验以津川1号为材料,设5个不同的氮肥处理,研究施氮量对水稻产量及品质的影响.结果表明,增施氮肥能够显著提高津川1号的产量,但施用过多氮肥会导致津川1号的碾磨品质、加工品质以及食味品质产生不同程度的降低.食味品质与蛋白质、直链淀粉含有率呈负相关关系.随着施氮量的增加,蛋白质和直链淀粉含有率随之增加,使津川1号食味品质明显劣化.

作为小站稻主产区,天津市宝坻区积极推动小站稻产业升级,在产业规划、土地流转、科技支撑、生态种植、三产融合、龙头带动、产村融合等方面做出积极实践与有益探索.在小站稻产业振兴中,宝坻区充分发挥党组织战斗堡垒作用,政府搭台百姓唱戏,因地制宜发展特色产业,科技支撑现代稻业发展,着眼世界打造知名品牌,这些宝贵经验为其他地区农业转型升级提供诸多启示.

Trichinella spiralis is an important foodborne pathogen that has been found to infect many kinds of mammalian species (Pozio, 2007). Human Trichinella infection is mainly caused from ingestion of raw or poorly cooked meat containing the infective larvae of Trichinella (Cui et al., 2013a). Outbreaks of trichinellosis have been reported in many countries, especially in developing countries. From 2004 to 2009, 15 trichinellosis outbreaks were reported in mainland China (Cui et al., 2011). The main infection source of trichinellosis is domestic pigs (Jiang et al., 2016; Rostami et al., 2017). This disease has become an important public health problem and gained an increasing attention worldwide. Therefore, it is necessary to develop the vaccines to block Trichinella infection transmission in food animals (Bai et al., 2017; Qi et al., 2018). After the infected muscle tissue is ingested and digested by the digestive enzymes, the muscle larvae (ML) are released and then activated into intestine infective larvae (IIL) by exposure to intestinal contents or bile (Ren et al., 2013). The IIL penetrate into the enteric epithelium and grow to adult worms (AWs). The IIL invasion of intestinal epithelium cells (IECs) is crucial for the establishment of Trichinella infection (Liu et al., 2013). Intestinal epithelium is not only the first host’s native innate defense barrier but also the principal interaction location between T. spiralis and the host (Long et al., 2015; Wang et al., 2017). Therefore, analysis of the interaction between T. spiralis proteins and the IECs is helpful to elucidate the mechanism of the Trichinella invasion of intestinal epithelium (Han et al., 2020; Hu et al., 2020b). Trichinella spiralis excretory/secretory (ES) proteins play an essential role in parasite invasion and regulating host immune responses (Bolas-Fernandez et al., 2006; Bien et al., 2012). In our previous studies, a T. spiralis aspartic protease2 (TsASP2; GenBank: 339237490) was identified from ES proteins of ML and IIL. Recombinant TsASP2 (rTsASP2) was

It is of great theoretical and practical significance to construct a scientific taste sensory evaluation method to obtain accurate and reliable data, so as to provide theoretical basis and technical support for the breeding and cultivation technology development of taste japonica rice varieties. In this study, sensory evaluation experiments were carried out based on statistical analysis. Through the analysis of variance of the evaluation results, the identification ability and hobbies of the evaluators were analyzed, and the correlation between them was discussed. The results show that there are significant differences between appraisers and varieties between the two repetitions of the comprehensive evaluation items investigated in this experiment, which verifies the repeatability of sensory evaluation and reveals the feasibility of taste sensory evaluation method. Among the 20 taste tasters participating in the taste evaluation experiment, 16 (80% of all) have low recognition ability for the taste comprehensive evaluation items, of which 6 (30% of all) have different hobbies from the overall tendency of all tasters, so they are considered not suitable to carry out taste evaluation as taste tasters. However, the results also show that the number of evaluators participating in this experiment who have both high recognition ability and high consistency with all hobbies is less. Therefore, in order to obtain more reliable results, it is very necessary to strengthen the training of appraisers and cultivate appraisers with high discrimination ability.

试验将10个品种水稻同一时间种植在相同外界条件中,排除环境差异分析得出,在遗传特性影响下,抗倒性强的品种比抗倒性弱的品种产量高,主要原因是每穗粒数增多.食味综合评价好的品种直链淀粉含有率低,米饭硬度黏度比小,抗倒性差,且均具有显著的相关性.

水稻食味与其理化特性密切相关.以5个粳稻品种(系)为材料,设置4个收获期,研究采收时间对稻米食味理化特性的影响,确定基于食味的供试水稻品种(系)最佳收获期.结果表明,随着收获时间的延迟,稻谷千粒重先增加后下降,抽穗后第55 d收获,千粒重大,籽粒饱满.抽穗后第55 d收获,直链淀粉含量较低,蒸煮米饭粘度最大,硬度/粘度较小.随着收获时间的延迟,蛋白质含量和米饭的食味值都是先增加后下降,抽穗后第55 d收获,蒸煮米饭的食味值最高.米饭的食味值与精米蛋白质含量和米饭硬度/粘度呈极显著负相关,与米饭硬度呈显著负相关,与米饭粘度呈极显著正相关.综上所述,抽穗后第55 d是供试水稻品种(系)确保食味的最佳收获期,直链淀粉和蛋白质含量较低,米饭质地适宜,食味值最高.

Trichinella spiralis is an important foodborne parasitic nematode that represents an enormous threat to the food safety of pork meat. The development of a preventive vaccine is valuable for the prevention and control of Trichinella infection in domestic pigs to ensure pork safety. Elastase is a trypsin-like serine protease that hydrolyzes the host's diverse tissue components and participates in parasite penetration, and it might be a novel vaccine target molecule. The aim of this study was to assess the protective immunity produced by vaccination with a novel Trichinella spiralis elastase-1 (TsE) in a mouse model. The results demonstrate that subcutaneous vaccination of mice with rTsE elicited a systemic humoral response (high levels of serum IgG and subclass IgG1/IgG2a and IgA) and significant local enteral mucosal sIgA responses. Anti-rTsE IgG recognized the native TsE at the cuticle, stichosome of intestinal infective larvae and adult worm (AW), and intrauterine embryos of female AW. The rTsE vaccination also produced a systemic and local mixed Th1/Th2 response, as demonstrated by clear elevation levels of Th1 cytokines (IFN-γ, IL-2) and Th2 cytokines (IL-4, IL-10) after spleen, mesenteric lymph node and Peyer's patch cells from immunized mice were stimulated with rTsE. The immunized mice exhibited a 52.19% reduction in enteral AW and a 64.06% reduction in muscle larvae after challenge infection. The immune response triggered by rTsE vaccination protected enteral mucosa from larval intrusion, suppressed larval development and reduced female fecundity. The results indicate that TsE may represent a novel target molecule for anti-T. spiralis vaccines.

Spirometra larvae are etiological agents of human sparganosis. However, the systematics of spirometrid cestodes has long been controversial. In order to determine the current knowledge on the evolution and genetic structure of Spirometra, an exhaustive population diversity analysis of spirometrid cestodes using the mitochondrial gene: cytochrome c oxidase subunit 1 (cox1) was performed. All publicly available cox1 sequences available in the GenBank and 127 new sequencing genes from China were used as the dataset. The haplotype identify, network, genetic differentiation and phylogenetic analysis were conducted successively. A total of 488 sequences from 20 host species, representing four spirometrid tapeworms (S. decipiens, S. ranarum, S. erinaceieuropaei and Sparganum proliferum) and several unclassified American and African isolates from 113 geographical locations in 17 countries, identified 45 haplotypes. The genetic analysis revealed that there are four clades of spirometrid cestodes: Clade 1 (Brazil + USA) and Clade 2 (Argentina + Venezuela) included isolates from America, Clade 3 contained African isolates and one Korean sample, and the remainders from Asia and Australia belonged to Clade 4; unclassified Spirometra from America and Africa should be considered the separate species within the genus; and the taxonomy of two Korea isolates (S. erinaceieuropaei KJ599680 and S. decipiens KJ599679) was still ambiguous and needs to be further identified. In addition, the demographical analyses supported population expansion for the total spirometrid population. In summary, four lineages were found in the spirometrid tapeworm, and further investigation with deeper sampling is needed to elucidate the population structure.

In previous studies, a Trichinella spiralis serine protease (TsSP) was identified in excretion/secretion (ES) products from intestinal infective L1 larvae (IIL1) using immunoproteomics. The complete cDNA sequence of TsSP gene was 1372 bp, which encoded 429 amino acids with 47.55 kDa. The TsSP was transcribed and expressed at all T. spiralis life cycle phases, as well as mainly located at the cuticle and stichosome of the parasitic nematode. Recombinant TsSP bind to intestinal epithelial cells (IEC) and promoted larva invasion, however, its exact function in invasion, development and reproduction are still unknown. The aim of this study was to confirm the biological function of TsSP during T. spiralis invasion and growth using RNA interference (RNAi) technology. The results showed that on 1 day after electroporation using 2.5 µM siRNA156, TsSP mRNA and protein expression of muscle larvae (ML) was suppressed by 48.35 and 59.98%, respectively. Meanwhile, silencing of TsSP gene by RNAi resulted in a 61.38% decrease of serine protease activity of ML ES proteins, and a significant reduction of the in vitro and in vivo invasive capacity of IIL1 to intrude into the IEC monolayer and intestinal mucosa. When mice were infected with siRNA 156-transfected larvae, adult worm and muscle larva burdens were decreased by 58.85 and 60.48%, respectively. Moreover, intestinal worm growth and female fecundity were evidently inhibited after TsSP gene was knockdown, it was demonstrated that intestinal adults became smaller and the in vitro newborn larval yield of females obviously declined compared with the control siRNA group. The results indicated that knockdown of TsSP gene by RNAi significantly reduced the TsSP expression and enzymatic activity, impaired larvae intrusion and growth, and lowered the female reproductive capacity, further verified that TsSP might participate in diverse processes of T. spiralis life cycle, it will be a new prospective candidate molecular target of anti-Trichinella vaccines.

采用酚反应鉴定籼粳稻类型,详细探讨影响酚反应的有关因素,提高酚反应的可操作性.结果 表明,浸泡时间、稻米形态和苯酚浓度对酚反应具有重要影响.为提高酚反应的可操作性,并确保试验结果的准确性,宜采用浓度为0.20％及其以上的苯酚水溶液浸泡稻谷或糙米,且浸泡时间至少72 h.酚反应操作简便、颜色变化容易观察,在籼粳稻类型快速鉴定中具有实用价值.

A T. spiralis serine protease 1.2 (TsSP1.2) was identified in the muscle larvae (ML) and intestinal larvae surface/excretory-secretory (ES) proteins by immunoproteomics. The aim of this study was to determine the TsSP1.2 function in the process of T. spiralis intrusion, growth and reproduction by using RNA interference (RNAi). RNAi was used to silence the expression of TsSP1.2 mRNA and protein in the nematode. On 2 days after the ML were electroporated with 2 µM of TsSP1.2-specific siRNA 534, TsSP1.2 mRNA and protein expression declined in 56.44 and 84.48%, respectively, compared with untreated ML. Although TsSP1.2 silencing did not impair worm viability, larval intrusion of intestinal epithelium cells (IEC) was suppressed by 57.18% (P < 0.01) and the suppression was siRNA-dose dependent (r = 0.976). Infection of mice with siRNA 534 transfected ML produced a 57.16% reduction of enteral adult burden and 71.46% reduction of muscle larva burden (P < 0.05). Moreover, silencing of TsSP1.2 gene in ML resulted in worm development impediment and reduction of female fertility. The results showed that silencing of TsSP1.2 by RNAi inhibited larval intrusion and development, and reduced female fecundity. TsSP1.2 plays a crucial role for worm invasion and development in T. spiralis life cycle, and is a potential vaccine/drug target against Trichinella infection.