Selection and validation of reference genes for RT-qPCR in adipose and longissimus dorsi muscle tissues of buffalo.

Real-time quantitative PCR (RT-qPCR) is widely used to measure and evaluate gene expression. The precision and reliability of RT-qPCR are critically dependent on the selection of suitable reference genes (RGs). In this study, an effort was made to identify the optimal RGs for RT-qPCR analysis of adipose and the longissimus dorsi muscle (LM) in buffaloes. RNA sequencing data were firstly analyzed to obtain 10 candidate genes (FKBP1A, C25H16orf72, PNRC2, IQGAP1, ATP5PD, RPL6, NDUFB4, TRA2A, CAPRIN1, and METAP2) that with high and stable expression across adipose tissues. Four other identified RGs (GAPDH, ACTB, TOP2B, and UXT) were selected as well. The expression stability of the candidate RGs was evaluated by three algorithms (geNorm, NormFinder, and BestKeeper) and then further validated by adipocyte and myocyte markers. Our results showed that UXT and TOP2B were the optimal RGs for RT-qPCR analysis across adipose tissues in buffaloes; three RGs, RPL6, UXT, and TOP2B, were the optimal RGs for RT-qPCR analysis across adipose and the LM tissues in buffaloes. This study provides significant information for improving the accuracy of gene expression in research on intramuscular fat deposition in buffaloes.

Comparative transcriptome analysis reveals that PCK1 is a potential gene affecting IMF deposition in buffalo.

BACKGROUND: In China, although buffaloes are abundant, beef is mainly obtained from cattle, and this preference is mainly attributed to the low intramuscular fat (IMF) content of buffalo. Genetic factors are an important driver that affects IMF deposition. RESULTS: To reveal the intrinsic factors responsible for the low IMF content of buffalo, mRNA expression patterns in muscle and adipose tissue between buffalo and cattle were characterized by RNA sequencing analysis. The IMF content in Nanyang cattle was higher than that in Xinyang buffalo. A total of 1566 mRNAs expressed in adipose tissue showed differential expression between the longissimus dorsi muscles of buffalo and cattle. Functional annotation suggested a difference in the glycolysis/gluconeogenesis pathway between the two species. The results of RT-qPCR analysis and gain-of-function experiments confirmed the positive association between the IMF content and phosphoenolpyruvate carboxykinase 1 (PCK1) expression in buffalo. In both mouse C2C12 cells and cultured bovine myocytes, the activity of the PCK1 promoter in buffalo is lower than that in cattle. However, in mouse 3T3-L1 adipocytes and cultured bovine adipocytes, the activity of PCK1 in buffalo promoter is higher than that in cattle. CONCLUSIONS: These results indicate the important role of PCK1 in buffalo IMF deposition and illustrate the differences between buffalo and cattle promoter activity that drive PCK1 expression. This research helps to establish a foundation for further studies investigating IMF deposition in buffalo.

Impact of human papillomavirus infection in semen on sperm progressive motility in infertile men: a systematic review and meta-analysis.

BACKGROUND: Human papillomavirus (HPV) has been considered as one of the most common sexually transmitted viruses that may be linked to unexplained infertility in men. The possible mechanisms underlying correlation between HPV infection and infertility could be related to the altered sperm parameters. Current studies have investigated the effect of HPV seminal infection on sperm quality in infertile men, but have shown inconsistent results. METHODS: We systematically searched PubMed, Embase, Web of Science and CNKI for studies that examined the association between HPV seminal infection and sperm progressive motility. Data were pooled using a random-effects model. Outcomes were the sperm progressive motility rate. Results are expressed as standardised mean difference (SMD) with 95% confidence interval (CI). Heterogeneity was evaluated by the I-square (I2) statistic. RESULTS: Ten studies were identified, including 616 infertile patients with HPV seminal infection and 2029 infertile controls without HPV seminal infection. Our meta-analysis results indicated that sperm progressive motility was significantly reduced in HPV-infected semen samples compared with non-infected groups [SMD:-0.88, 95% CI:-1.17 ~ - 0.59]. There existed statistical heterogeneity (I2 value: 86%) and the subgroup analysis suggested that study region might be the causes of heterogeneity. CONCLUSIONS: HPV semen infection could significantly reduce sperm progressive motility in infertile individuals. There were some limitations in the study such as the differences in age, sample sizes and the number of HPV genotypes detected. Further evidences are needed to better elucidate the relationship between HPV seminal infection and sperm quality.

Ultrafast internal conversion dynamics of bilirubin bound to UnaG and its N57A mutant.

Fluorescent proteins (FPs) have become fundamental tools for live cell imaging. Most FPs currently used are members of the green fluorescent protein super-family, but new fluorophores such as bilin-FPs are being developed and optimized. In particular, the UnaG FP incorporates bilirubin (BR) as a chromophore, enhancing its fluorescence quantum yield by three orders of magnitude relative to that in solution. To investigate the mechanism of this dramatic enhancement and provide a basis for further engineering of UnaG and other tetrapyrrole-based fluorophores, we performed picosecond fluorescence and femtosecond transient absorption measurements of BR bound to UnaG and its N57A site-directed mutant. The dynamics of wt-UnaG, which has a fluorescence QY of 0.51, are largely homogeneous, showing an excited state relaxation of ∼200 ps, and a 2.2 ns excited-state lifetime decay with a kinetic isotope effect (KIE) of 1.1 for D2O vs. H2O buffer. In contrast, for UnaG N57A (fluorescence QY 0.01) the results show a large spectral inhomogeneity with excited state decay timescales of 47 and 200 ps and a KIE of 1.4. The non-radiative deactivation of the excited state is limited by proton transfer. The loss of direct hydrogen bonds to the endo-vinyl dipyrrinone moiety of BR leads to high flexibility and structural heterogeneity of UnaG N57A, as seen in the X-ray crystal structure.

Wenshen Jianpi recipe, a blended traditional Chinese medicine, ameliorates proteinuria and renal injury in a rat model of diabetic nephropathy.

BACKGROUND: Wenshen Jianpi recipe (WSJPR), a blended traditional Chinese medicine, is considered to have the possible beneficial effect on the progression of diabetic nephropathy (DN). This present study was designed to elucidate this protective activity in a rat model with streptozotocin (STZ)-induced DN and to explore the possible underlying mechanism. METHODS: Adult Sprague Dawley (SD) rats were induced to develop DN through intraperitoneal injection of STZ (60 mg/kg). Animals were orally administered saline, WSJPR at 7.5, 15, 30 g/kg, and valsartan (25 mg/kg) daily for 8 weeks. Blood and 24-h urine samples of each rat were collected for biochemical examination at 2-week intervals. Microcirculatory blood flow in the renal cortex and hemorheology index were also measured. At the end of 8 weeks, all rats were sacrificed to obtain the kidney tissues for histological examination and reverse transcription polymerase chain reaction (RT-PCR) was used to analyze the transcriptional levels of nephrin and podocin genes. RESULTS: WSJPR could improve serum total protein (TP) and albumin (ALB), reduce the excretion rates of urine-TP (U-TP), urine-ALB (U-ALB) and urine urea nitrogen (UUN) (P < 0.05), although it did not significantly alter the hyperglycemia. In addition, treatment with WSJPR could strongly reduce blood flow, erythrocyte aggregation index, and ameliorate microcirculation. In histological measurement, WSJPR-treated rats showed a significant amelioration in glomerular hypertrophy and mesangial expansion. By RT-PCR, we found WSJPR up-regulated the nephrin and podocin expression at mRNA levels. CONCLUSION: This study suggested that WSJPR could effectively relieve renal damage and improve renal function of DN rats by ameliorating metabolism disorder and increasing the gene expression of nephrin and podocin, which might be a useful approach for the treatment of DN.

Plasmon-Enhanced Ultrasensitive Surface Analysis Using Ag Nanoantenna.

Raman scattering and fluorescence spectroscopy permeate analytic science and are featured in the plasmon-enhanced spectroscopy (PES) family. However, the modest enhancement of plasmon-enhanced fluorescence (PEF) significantly limits the sensitivity in surface analysis and material characterization. Herein, we report a Ag nanoantenna platform, which simultaneously fulfills very strong emission (an optimum average enhancement of 105-fold) and an ultrafast emission rate (∼280-fold) in PES. For applications in surface science, this platform has been examined with a diverse array of fluorophores. Meanwhile, we utilized a finite-element method (FEM) and time-dependent density functional theory (TD-DFT) to comprehensively investigate the mechanism of largely enhanced radiative decay. PES with a shell-isolated Ag nanoantenna will open a wealth of advanced scenarios for ultrasensitive surface analysis.

Proteomic profile of human spermatozoa in healthy and asthenozoospermic individuals.

Asthenozoospermia is considered as a common cause of male infertility and characterized by reduced sperm motility. However, the molecular mechanism that impairs sperm motility remains unknown in most cases. In the present review, we briefly reviewed the proteome of spermatozoa and seminal plasma in asthenozoospermia and considered post-translational modifications in spermatozoa of asthenozoospermia. The reduction of sperm motility in asthenozoospermic patients had been attributed to factors, for instance, energy metabolism dysfunction or structural defects in the sperm-tail protein components and the differential proteins potentially involved in sperm motility such as COX6B, ODF, TUBB2B were described. Comparative proteomic analysis open a window to discover the potential pathogenic mechanisms of asthenozoospermia and the biomarkers with clinical significance.

The Protective Effect of a Long-Acting and Multi-Target HM-3-Fc Fusion Protein in Rheumatoid Arthritis.

Current treatment of rheumatoid arthritis (RA) is limited by relative shortage of treatment targets. HM-3 is a novel anti-RA polypeptide consisting of 18 amino acids with integrin αVß3 and α5ß1 as targets. Previous studies confirmed that HM-3 effectively inhibited the synovial angiogenesis and the inflammatory response. However, due to its short half-life, the anti-RA activity was achieved by frequent administration. To extend the half-life of HM-3, we designed a fusion protein with name HM-3-Fc, by combination of modified Fc segment of immunoglobulin 4 (IgG4) with HM-3 polypeptide. In vitro cell experiments demonstrated that HM-3-Fc inhibited the proliferation of splenic lymphocytes and reduced the release of TNF-α from macrophages. The pharmacodynamics studies on mice paw in Collagen-Induced Arthritis (CIA) model demonstrated that HM-3-Fc administered once in 5 days in the 50 and 25 mg/kg groups, or once in 7 days in the 25 mg/kg group showed a better protective effect within two weeks than the positive control adalimumab and HM-3 group. Preliminary pharmacokinetic studies in cynomolgus confirmed that the in vivo half-life of HM-3-Fc was 15.24 h in comparison with 1.32 min that of HM-3, which demonstrated that an Fc fusion can effectively increase the half-life of HM-3 and make it possible for further reduction of subcutaneous injection frequency. Fc-HM-3 is a long-acting active molecule for RA treatment.

Ratiometric fluorescent pH nanoprobes based on in situ assembling of fluorescence resonance energy transfer between fluorescent proteins.

pH-dependent protein adsorption on mesoporous silica nanoparticle (MSN) was examined as a unique means for pH monitoring. Assuming that the degree of protein adsorption determines the distance separating protein molecules, we examined the feasibility of nanoscale pH probes based on fluorescence resonance energy transfer (FRET) between two fluorescent proteins (mTurquoise2 and mNeonGreen, as donor and acceptor, respectively). Since protein adsorption on MSN is pH-sensitive, both fluorescent proteins were modified to make their isoelectric points (pIs) identical, thus achieving comparable adsorption between the proteins and enhancing FRET signals. The adsorption behaviors of such modified fluorescent proteins were examined along with ratiometric FRET signal generation. Results demonstrated that the pH probes could be manipulated to show feasible sensitivity and selectivity for pH changes in hosting solutions, with a good linearity observed in the pH range of 5.5-8.0. In a demonstration test, the pH probes were successfully applied to monitor progress of enzymatic reactions. Such an "in situ-assembling" pH sensor demonstrates a promising strategy in developing nanoscale fluorescent protein probes. Graphical abstract Working principle of the developed pH sensor TNS; and FRET Ratio (I528/I460) as a function of pH under different protein feed ratios (mNeonGreen to mTurquoise2).

pH-sensitive pHluorins as a molecular sensor for in situ monitoring of enzyme-catalyzed prodrug activation.

This work examines the feasibility of using a pH-sensitive fluorescent protein as a molecular reporter for enzyme-catalyzed prodrug activation reaction. Specifically, a ratiometric pHluorins was examined for detection of the activity of horseradish peroxidase (HRP) for the activation of indole-3-acetic acid. The pHluorins and HRP were conjugated chemically, forming a biocatalyst with a self-reporting function. Results showed that the characteristic fluorescence intensity ratio of the conjugate shifted from 1.47 to 1.40 corresponding to the progress of the prodrug activation reaction. The effectiveness of applying the conjugate for inhibition of the growth of Bcap-37 cells was also demonstrated simultaneously with reaction monitoring. The results reveal a very promising approach to realizing in situ monitoring of enzyme activities based on pH shifting for enzyme-based prodrug therapy applications.

Biochemical properties and vaccine effect of recombinant TPx-3 from Schistosoma japonicum.

Thioredoxin peroxidases (TPxs) play an important role in maintaining redox homeostasis and in protecting organisms from the accumulation of toxic reactive oxygen species (ROS). In this study, we isolated the thioredoxin peroxidase-3 gene of Schistosoma japonicum, SjTPx-3. The open reading frame (ORF) of SjTPx-3 was 663 bp encoding 220 amino acids with a molecular weight of 24.99 kDa and an isoelectric point of 6.20. Quantitative real-time reverse transcription-polymerase chain reaction indicated that SjTPx-3 was expressed in all different stages of the parasites, with highest expression in 35-day-old worms. The ORF of SjTPx-3 was subcloned into pET-32a (+) vectors and expressed in Escherichia coli. Recombinant SjTPx-3 (rSjTPx-3) was expressed as a soluble protein with good antigenicity, as demonstrated by western blotting. Immunohistochemical analysis revealed that SjTPx-3 was mainly localized on the tegument of the parasites. Mice vaccinated with rSjTPx-3 had a 37.02% (P < 0.05) reduction in worm burden and 56.52% (P < 0.05) reduction in liver egg production compared with control, unvaccinated mice. Enzyme-linked immunosorbent assay analysis demonstrated that rSjTPx-3 could induce high levels of anti-rSjTPx-3-specific IgG, IgG1, and IgG2a antibodies. Characteristic Th1 and Th2 immune response cytokines were detected by flow cytometry and were increased by rSjTPx-3. Taken together, these results suggest that SjTPx-3 is an antioxidant enzyme responsible for protecting S. japonicum from oxidative stress. rSjTPx-3 may represent a potential vaccine candidate and/or new drug target for patients with schistosomiasis.

[Hepatitis B virus infection increases the incidence of immune infertility in males].

OBJECTIVE: To investigate the relationship between hepatitis B virus (HBV) infection and the incidence of male immune infertility. METHODS: Based on the levels of serum HBsAg, 3 124 infertile men were classified into an HBV-positive and an HBV-negative group and, according to the results of IBT tests, those with immune infertility were further divided into an HBV-positive and an HBV-negative group. Statistical analyses were made on the incidence rate of immune infertility and seminal parameters in the immune infertility patients of the HBV-positive and HBV-negative groups, the correlation of the number of HBV DNA copies in the serum with that in the seminal plasma of the HBV-positive patients, the association of the numbers of HBV DNA copies in the serum and seminal plasma with semen parameters, and the relationship of the number of HBV DNA copies in the seminal plasma with the incidence of immune infertility. Sperm concentration and the percentage of progressively motile sperm (PMS) were measured by computer-aided sperm analysis, sperm morphology determined by Diff-Quik staining, the level of HBsAg detected by ELISA, and the numbers of HBV DNA copies in the serum and seminal plasma calculated by RT-PCR. RESULTS: The incidence rate of immune infertility was significantly higher in the HBV-positive than in the HBV-negative group (20.3 vs 3.3%, χ2 = 187.5, P <0.01), and the percentage of morphologically normal sperm (MNS) was markedly lower in the HBV-positive than in the HBV-negative infertility patients (ï¼»3.9 ± 1.7ï¼½ vs ï¼»6.3 ± 2.2ï¼½%, P <0.05), but no statistically significant differences were observed between the two groups of infertile males in the semen volume, sperm concentration, or PMS (P >0.05). The number of HBV DNA copies in the serum was positively correlated with that in the seminal plasma (rs = 0.86, P <0.01) while both the number of HBV DNA copies in the serum and that in the seminal plasma were negatively correlated with PMS (r = －0.233 and －0.465, P <0.01) and MNS (r = －0.250 and －0.508, P <0.01). The incidence rate of immune infertility showed no statistically significant differences among the groups with different numbers of HBV DNA copies in the seminal plasma (P >0.05). CONCLUSIONS: HBV infection can increase the incidence rate of immune infertility in men and is correlated with the low quality of sperm.

[Fluorescence Properties of Single-Trp Peptide: Response to pH and Metal Ions].

Considering the important role of metal ions including copper ions are playing in human body, a novel single-Trp peptide WDAHSS was designed and synthesized in this study to achieve sensitive detection of copper ions via fluorescence spectroscopy. The intrinsic fluorescence of a tryptophan residue in WDAHSS, which was the only source of the molecular fluorescence, could be easily quenched with copper ions. By comparing fluorescence spectra of WDAHSS with those of tryptophan molecules at different pH values, the quenching mechanism of WDAHSS was explored in detail. Research showed that the histidine in WDAHSS bound copper ions with metal coordination. With participation of peptide bond, a square planar structure was formed. It was a consequent chelation of copper ions that caused the quenching of tryptophan residue. At the same time, this study discussed how pH conditions affected the fluorescence spectra of WDAHSS. Furthermore, association constants of copper ions towards WDAHSS were calculated through fluorescence measurements and fitting analyses. To enhance the anti-jamming ability to pH variation, the amino terminal of WDAHSS was intentionally acetylized, leading to a stable fluorescence emission under physiological pH conditions. Besides, WDAHSS was designed as a special structure to enhance the selectivity and biocompatibility of its sensitive detection of copper ions. Further studies on WDAHSS may help to improve the fluorescence imaging detection in vivo.

[Precise and Rapid Detection of Glutathione by Using Novel Fluorescent Ag Nanoclusters].

Glutathione (GSH) is an important three-peptide molecule, which has the functions of antioxidation and detoxification, and plays a crucial role in the fields of biology, medicine and food science. It is involved in many important biochemical reactions in cells and body fluid, and the changes of GSH content reflect the specific health problems of human body. Current methods of GSH detection are always complicated, time-consuming and expensive instrument depended, such as surface enhanced Raman spectroscopy (SERS), electrochemical analysis, high performance liquid chromatography (HPLC) and so on. The probe's photochemical properties can be modified by the reaction between GSH and nanoclusters, which will result in the changes of fluorescence intensity and wavelength. In this paper, a new method to realize precise and rapid GSH detection is developed by using silver na-noclusters as a fluorescent probe, and simultaneously measures the probe's fluorescence intensity and wavelength. The synthesis of the fluorescence probe reported in this paper possesses the advantages of steps-simple and pollution free, and the GSH detection method has faster response, more accurate measurement and smaller relative error over the traditional methods. The good specificity of GSH detection among other molecules with the similar structure is further proved in control group experiments by comparing the differences of their fluorescence intensities and wavelength. The measurement accuracy is fully assured due to the insensitivity of the probe to a variety of salt ions and amino acids. This technique can be further employed in the intracellular detection and imaging of GSH.

Printed microwells with highly stable thin-film enzyme coatings for point-of-care multiplex bioassay of blood samples.

A paper-based colorimetric biosensor suitable for point-of-care bioassay of blood samples is developed using highly stable enzyme thin-film coatings confined within inkjet printed polymeric microwells. The microwells are developed through a simple one-step inkjet printing of hydrophobic polystyrene on paper, with walls formed by the polymer that fills the gaps inside the paper body. The microwells can also be patterned to be interlinked with printed microchannels for multiplex bioassays. Thin film enzyme coatings confined within the microwells are then constructed, thereby constituting biosensors that work like traditional microwell plates, yet allow easy colorimetric readouts with naked eyes or portable devices, such as smart phones. The efficiency of the paper-based sensor was demonstrated for colorimetric assays of glucose and lactate, both as individual analytes or mixed, as well as samples with red blood cells. Such sensors showed good sensitivities within the concentration ranges of the analytes in human blood (0.5-10 mM), with a visible sensitivity of <0.5 mM detectable by naked eyes for a sample size as small as 1 µL. More accurate digital readouts were shown to be feasible with computerized scanners or smartphones. The thin-film coating format affords the paper biosensors an extended lifetime, and they could retain 100% performance over 6 months of storage at room temperature, or up to one month heated at 50 °C, which promises refrigeration-free storage of the sensor. The simple preparation, high enzyme stability and ease-of-use of the paper-based sensor promise low-cost and reliable point-of-care multiplex bioassay for biomedical diagnostics.

Cloning, expression and enzymatic characterization of 3-phosphoglycerate kinase from Schistosoma japonicum.

In the present study, a full-length cDNA encoding the Schistosoma japonicum 3-phosphoglycerate kinase (SjPGK) with an open reading frame of 1251 bp was isolated from 42-day-old (42-d) schistosome cDNAs. Real-time quantitative reverse transcription PCR analysis revealed that SjPGK was expressed in all investigated developmental stages and at a higher transcript levels in 21- and 42-d worms. Moreover, the SjPGK mRNA level was significantly downregulated in 10-d schistosomula from Wistar rats (non-susceptible host). SjPGK was subcloned into pET28a(+) and expressed as both supernatant and inclusion bodies in Escherichia coli BL21 cells. The enzymatic activity of recombinant SjPGK protein (rSjPGK) was 125 U/mg. Kinetic analyses with respect to 3-phosphoglycerate (3-PGA) as substrate gave a Km of 2.69 mmol/L and a Vmax of 748 µmol/min/mg protein. rSjPGK was highly stable over a range of pH 8.0-9.0 and temperature of 30°C-40 °C under physiological conditions. Immunolocalization analysis showed that SjPGK was mainly distributed in the tegument and parenchyma of schistosomes. Western blotting showed that rSjPGK had good immunogenicity. We vaccinated BALB/c mice with rSjPGK combined with Seppic 206 adjuvant. However, there were no significant reductions in the numbers of worms of eggs in the liver, as compared to adjuvant or blank control groups in two independent vaccination tests. This study provides the basis for further investigations into the biological function of SjPGK, although it might not be suitable as a potential vaccine candidate against schistosomiasis.

Horseradish peroxidase-encapsulated chitosan nanoparticles for enzyme-prodrug cancer therapy.

Among various enzyme-based therapies, enzyme-prodrug therapy (EPT) promises minimized side effects in that it activates non-toxic prodrugs locally where the enzymes are placed. The success of such an approach requires high enzyme stability against both structural denaturation and potential immunogenicity. This work examines the efficiency of nanoparticles for enzyme protection in EPT applications. Specifically, horseradish peroxidase (HRP)-encapsulated chitosan nanoparticles (HRP-CSNP) were constructed and examined with respect to stability enhancement. HRP-CSNP retained enzyme activity and had improved stability at 37 °C in the presence of a denaturant, urea. The nanoparticles effectively bound to the surface of human breast cancer cell Bcap37 and led to over 80 % cell death when applied with a prodrug indole-3-acetic acid.

Expression and characterization of recombinant humanized anti-HER2 single-chain antibody in Pichia pastoris for targeted cancer therapy.

OBJECTIVES: The availability of self-targeting and low immunogenic therapeutic agents is critical to efficient cancer therapy. Therefore, the development of humanized therapeutic antibodies is particularly appealing. RESULTS: A humanized single-chain variable fragment (scFv) antibody that can target human epidermal growth factor receptor-2 (HER2)-overexpressing cancer cells was designed and produced via expression in Pichia pastoris. The expression gave a high yield of 8 mg protein/l (with a purity of 92 %) using shake-flask cultures. Functional studies also revealed that the purified recombinant anti-HER2 scFv exhibited anti-proliferative activity and could bind efficiently to HER2-overexpressing human breast cancer cell line SKBR3. CONCLUSION: The recombinant scFv offers promising therapeutic and binding efficiencies that are desirable for targeted cancer therapies.

Cloning, expression and characterization of protein disulfide isomerase of Schistosoma japonicum.

The excretory/secretory (ES) proteins of schistosomes play important roles in modulating host immune systems and are regarded as potential vaccine candidates and drug targets. Protein disulfide isomerase (PDI) is an essential enzyme that is involved in disulfide bond formation and rearrangement. In the present study, SjPDI, a 52.8 kDa protein previously identified in a proteomics analysis as one of the ES proteins of Schistosoma japonicum, was cloned and characterized. Western blot analysis showed that recombinant SjPDI (rSjPDI) was recognized by serum from rabbits vaccinated with schistosome worm antigen. Worm protein extracts and ES protein extracts from S. japonicum could react with anti-rSjPDI mouse serum. Real-time PCR analysis indicated that SjPDI was expressed at all developmental stages tested, and a high expression level was detected in 42-day-old male worms. Immunofluorescence analysis revealed that SjPDI was mainly distributed on the tegument and parenchyma of S. japonicum worms. An enzyme-linked immunosorbent assay (ELISA) demonstrated that rSjPDI could induce a high level of rSjPDI-specific IgG antibodies. The biological activity of purified rSjPDI was confirmed by isomerization and antioxidative activity assays. The 35.32%, 26.19% reduction in the worm burden and 33.17%, 31.7% lower liver egg count were obtained in mice vaccinated with rSjPDI compared with the blank control group in two independent trials. Our preliminary results suggest that rSjPDI plays an important role in the development of the schistosome and is a potential vaccine candidate for schistosomiasis.

High Energy Density in All-Organic Polyimide-Based Composite Film by Doping of Polyvinylidene Fluoride-Based Relaxor Ferroelectrics.

Recently, due to the advantages of superior compatibility, fewer interface defects, and a high electric breakdown field, all-organic dielectric composites have attracted significant research interest. In this investigation, we produced all-organic P(VDF-TrFE-CFE) terpolymer/PI (terp/PI) composite films by incorporating a small amount of terpolymer into PI substrates for high energy density capacitor applications. The resulting terp/PI-5 (5% terpolymer) composite films exhibit a permittivity of 3.81 at 1 kHz, which is 18.7% greater than that of pristine PI (3.21). Furthermore, the terp/PI-5 film exhibited the highest energy density (9.67 J/cm3) and a relatively high charge-discharge efficiency (84.7%) among the terp/PI composite films. The energy density of the terp/PI-5 film was increased by 59.8% compared to that of the pristine PI film. The TSDC results and band structure analysis revealed the presence of deeper traps in the terp/PI composites, contributing to the suppression of leakage current and improved charge-discharge efficiency. Furthermore, durability tests confirm the stability of the composite films under extended high-temperature exposure and cycling, establishing their viability for practical applications.