Nanopeptide CI20 remarkably enhances growth performance and disease resistances by improving the mucosal structure, antioxidant capacity, and immunity in mandarin fish (Siniperca chuatsi)

Soybean meal, excessively used in place of fish meal (FM) in aquaculture, has a detrimental impact on fish. In this study, the nanopeptide CI20, which was created by conjugating antimicrobial peptide gcIFN-20H and CMCS, were evaluated the feeding effect in mandarin fish (Siniperca chuatsi). Compared with the control group, 150 mg/kg C-I20-fed fish showed the second highest growth performance with no significant changes in body composition. C-I20-fed fish showed more goblet cells and thicker mucin after feeding. The 150 mg/kg CI20 diet boosted the antioxidant capacity, immunity, and digestive enzymes. After Aeromonas hydrophila and infection spleen and kidney necrosis virus infection, the survival rates in the 150 mg/kg CI20 group were highest. Meanwhile, many tissues in the 150 mg/kg CI20 group had significantly lower pathogen loads than the other groups. Treatment with 150 mg/kg CI20 was effective in increasing antioxidant capacity and immunity. The minimum tissue lesions were observed in the 150 mg/kg CI20 group. The goblet cell number and mucin thickness were significantly increased by CI20 treatment after infection. The study results herein showed that a reasonable dietary concentration of CI20 feed promoted growth performance and disease resistances in fish, suggesting a prospective nano antimicrobial peptide for the aquaculture.

Vitamin D3 can effectively and rapidly clear largemouth bass ranavirus by immunoregulation

Largemouth bass ranavirus (LMBV) is a highly destructive pathogen that causes significant mortality rates among largemouth bass populations. Unfortunately, there is a dearth of drug development efforts specifically aimed at treating LMBV. To address this, our study sought to investigate the potential effectiveness of incorporating varying doses of VD3 into the diet as a treatment for LMBV. Through qRT-PCR and semi-qPCR, we observed significant suppression and clearance of LMBV pathogens in largemouth bass fed with 15000 IU/Kg and 20000 IU/Kg of VD3 within 14 days. In addition, VD3 treatment significantly increased the expression levels of key immune-related genes such as IL-1β, IFN-γ, Mx, and IgM. Encouragingly, we observed that VD3 significantly increased antioxidant and immune activities such as TSOD, TAOC and C3 in serum and maintained total protein levels. Additionally, tissue pathology sections highlighted a dose-dependent relationship between VD3 supplementation and tissue damage, with the 15000 IU and 20000 IU groups exhibiting minimal damage. In conclusion, a reasonable concentration of VD3 effectively reduced LMBV replication and tissue damages, while improved immune-related genes expression and serum biochemical indices. These findings declare the considerable therapeutic potential of VD3 supplementation for combating LMBV disease and provide an alternative treatment option for fish farming.

The oral antigen-adjuvant fusion vaccine P-MCP-FlaC provides effective protective effect against largemouth bass ranavirus infection

Largemouth bass ranavirus (LMBV) is highly contagious and lethal to largemouth bass, causing significant economic losses to the aquaculture industry. Oral vaccination is generally considered the most ideal strategy for protecting fish from viral infection. In this study, the fusion protein MCP-FlaC, consisting of the main capsid protein (MCP) as the antigen and flagellin C (FlaC) as the adjuvant, was intracellularly expressed in Pichia pastoris. Subsequently, the recombinant P. pastoris was freeze-dried to prepare the oral vaccine P-MCP-FlaC. Transmission electron microscopy and scanning electron microscopy analysis showed that the morphology and structure of the freeze-dried recombinant P. pastoris vaccine remained intact. The experiment fish (n = 100) was divided into five groups (P-MCP-FlaC, P-MCP, P-FlaC, P-pPIC3.5K, control) to evaluate the protective efficacy of the recombinant vaccine. Oral P-MCP-FlaC vaccine effectively up-regulated the serum enzymes activity (total superoxide dismutase, lysozyme, total antioxidant capacity, and complement component 3). The survival rate of P-MCP-FlaC group was significantly higher than that of the other groups. The mRNA expression of crucial immune genes (IL-1β, TNF-α, MHC-II, IFN-γ, Mx, IgM, IgT) was also signally elevated in P-MCP-FlaC group. Vaccine P-MCP-FlaC markedly inhibited the replication of LMBV in the spleen, head kidney, and intestine, while reducing the degree of lesion in the spleen. These results suggest that the oral P-MCP-FlaC vaccine could effectively control LMBV infection, proving an effective strategy for viral diseases prevention in aquaculture.

The Combination of β-Glucan and Astragalus Polysaccharide Effectively Resists Nocardia seriolae Infection in Largemouth Bass (Micropterus salmoides)

Effectively treating and preventing outbreaks is crucial for improving the economic benefits of aquaculture. Therefore, utilizing immunostimulants, either alone or in combination, is regarded as a promising strategy. In this study, β-glucan + APS (200 mg/kg + 200 mg/kg), β-glucan (200 mg/kg), APS (200 mg/kg), enrofloxacin (15 mg/kg), and sulfadiazine (15 mg/kg) were added to feed to assess the effects against Nocardia seriolae infection in largemouth bass (Micropterus salmoides) within 14 days. The survival rates did not differ between the enrofloxacin group and the β-glucan + APS group, but both were significantly higher than that of the control group. Additionally, the enrofloxacin group and the β-glucan + APS group exhibited the lowest bacterial loads and tissue damage. Importantly, the β-glucan + APS treatment significantly improved serum enzyme activities (total superoxide dismutase, lysozyme, total protein) and the expression of immune genes (IL-1β, TNF-α, IFN-γ, IgM) compared to the other treatment groups. The enrofloxacin group showed similar efficacy to the β-glucan + APS group in combating N. seriolae infection, but N. seriolae in the enrofloxacin group developed drug resistance. In summary, the combined use of β-glucan and APS is a promising strategy for treating bacterial diseases, thereby contributing to the promotion of sustainable aquaculture development.

VP4/VP56/VP35 Virus-like Particles Effectively Protect Grass Carp (Ctenopharyngodon idella) against GCRV-II Infection

Grass carp reovirus (GCRV) seriously threatens the grass carp (Ctenopharyngodon idella) industry. Prophylactic GCRV vaccines prepared by virus-like particle (VLP) assembly biotechnology can improve effectiveness and safety. The highly immunogenic candidate antigens of GCRV vaccines that have been generally considered are the outer capsid proteins VP4, VP56, and VP35. In this study, VP4, VP56, and VP35 were expressed in an Escherichia coli expression system and a Pichia pastoris expression system. The successful assembly of uniform, stable, and non-toxic VP4/VP56/VP35 VLPs was confirmed through various assays. After vaccination and GCRV infection, the survival rate in the VLPs + adjuvant Astragalus polysaccharide (APS) group was the highest (62%), 40% higher than that in control group (22%). Through the antibody levels, tissue viral load, and antioxidant immunity assays, the P. pastoris VLP vaccine effectively improved IgM levels, alleviated tissue virus load, and regulated antioxidant immune-related indicators. The treatment with P. pastoris VLPs enhanced the mRNA expression of important immune-related genes in the head kidney, as measured by qRT-PCR assay. Upon hematoxylin-eosin staining examination, relatively reduced tissue pathological damage was observed in the VLPs + APS group. The novel vaccine using P. pastoris VLPs as an effective green biological agent provides a prospective strategy for the control of fish viral diseases.

Type II Grass Carp Reovirus Rapidly Invades Grass Carp (Ctenopharyngodon idella) via Nostril-Olfactory System-Brain Axis, Gill, and Skin on Head

Type II grass carp reovirus (GCRV-II) with high pathogenicity and infectivity causes severe hemorrhagic disease, which leads to extensive death in the grass carp and black carp aquaculture. However, the early invasion portal remains unclear. In this study, we explored the invasion portal, time, and pathway of GCRV-II by immersion infection in grass carp. Through the detection of the infected grass carp external body surface tissues, most of them could be detected to carry GCRV-II within 45 min except for the skin covered by scales. Further shortening the duration of infection, we proved that GCRV-II rapidly invades through the nostril (especially), gill, and skin on head at only 5 min post-immersion, rather than merely by adhesion. Subsequently, visual localization investigations of GCRV-II were conducted on the nostril, olfactory system (olfactory bulb and olfactory tract), and brain via immunofluorescence microscopy and transmission electron microscopy. We found that few viruses were located in the nostril at 5 min post-immersion infection, while a significantly increased quantity of viruses were distributed in all of the examined tissues at 45 min. Furthermore, the semi-qRT-PCR and Western blotting results of different infection times confirmed that GCRV-II invades grass carp via the nostril-olfactory system-brain axis and then viral replication unfolds. These results revealed the infection mechanism of GCRV-II in terms of the invasion portal, time, and pathway in grass carp. This study aims to understand the invasion mode of GCRV-II in grass carp, thus providing theoretical support for the prevention and control strategies of hemorrhagic disease.

Nanopeptide C-I20 as a novel feed additive effectively alleviates detrimental impacts of soybean meal on mandarin fish by improving the intestinal mucosal barrier

Antibacterial peptide has been widely developed in cultivation industry as feed additives. However, its functions in reducing the detrimental impacts of soybean meal (SM) remain unknown. In this study, we prepared nano antibacterial peptide CMCS-gcIFN-20H (C-I20) with excellent sustained-release and anti-enzymolysis, and fed mandarin fish (Siniperca chuatsi) with a SM diet supplemented with different levels of C-I20 (320, 160, 80, 40, 0 mg/Kg) for 10 weeks. 160 mg/Kg C-I20 treatment significantly improved the final body weight, weight gain rate and crude protein content of mandarin fish and reduced feed conversion ratio. 160 mg/Kg C-I20-fed fish maintained appropriate goblet cells number and mucin thickness, as well as improved villus length, intestinal cross-sectional area. Based on these advantageous physiological changes, 160 mg/Kg C-I20 treatment effectively reduced multi-type tissue (liver, trunk kidney, head kidney and spleen) injury. The addition of C-I20 did not change the muscle composition and muscle amino acids composition. Interestingly, dietary 160 mg/Kg C-I20 supplementation prevented the reduction in myofiber diameter and change in muscle texture, and effectively increased polyunsaturated fatty acids (especially DHA + EPA) in muscle. In conclusion, dietary C-I20 in a reasonable concentration supplementation effectively alleviates the negative effects of SM by improving the intestinal mucosal barrier. The application of nanopeptide C-I20 is a prospectively novel strategy for promoting aquaculture development.

Editorial: The society for environmental geochemistry and health (SEGH): 50 years and beyond

When the SEGH international board released a short editorial paper back in 2019, we described an aim to increase the membership offering, whilst improving the diversity of input regionally, by scientific discipline and to ensure greater and more regular contact across the regions from 2020 onwards. Wider aspirations described in 2019 (Watts et al. 2019) are discussed within this short communication at the end of 2021 to evaluate progress made. In particular, how the SEGH community adapted to the unprecedented circumstances that have challenged each and every one of us throughout the COVID-19 pandemic since early 2020 and are likely to influence our activities for the foreseeable future.

IFN1 Enhances Thrombocyte Phagocytosis through IFN Receptor Complex-JAK/STAT-Complement C3.3-CR1 Pathway and Facilitates Antibacterial Immune Regulation in Teleost

Type I IFNs with strong positive charges exhibit robust bactericidal activity and a protective effect against bacterial infections. However, the antibacterial mechanism in vivo remains unknown. In this study, Ab blockade of IFN1, a member of type I IFNs in grass carp (Ctenopharyngodon idella), resulted in high mortality, tissue bacterial loads, and low expression of immune factors after bacterial challenge, which indicates that the antibacterial activity of IFN1 has physiological significance. Meanwhile, we injected grass carp with the recombinant and purified intact IFN1 protein after bacterial injection, and the result demonstrated a remarkable therapeutic effect. Furthermore, we found that IFN1 expression was remarkably induced in blood cells after bacterial challenge, and prophagocytosis via IFN1 mostly increased in thrombocytes. Then, we isolated peripheral blood thrombocytes by polyclonal Ab of CD41 and stimulated thrombocytes with recombinant IFN1, and the results indicated that immune factors and complement components (especially C3.3) were induced. Unexpectedly, complements demonstrated not only bacteriolysis but also bacterial aggregation. Furthermore, Ab blockades of the three subunits (CRFB1/CRFB2/CRFB5) of the IFN1 receptor or inhibition of STAT1 almost abolished the prophagocytosis via IFN1 and reduced C3.3 and immune factor expression in thrombocytes. Meanwhile, Ab blockade of the complement receptor CR1 greatly attenuated the prophagocytosis of IFN1. In contrast, mouse IFN-β did not show the promotion of antibacterial activity. These results clarify the prophagocytosis and immune regulation pathways of IFN1 in antibacterial immunity in teleosts. This study reveals the antibacterial mechanisms of type I IFNs in vivo and inspires functional studies of IFN in bacterial infections.

Androgens in endometrial carcinoma: the killer or helper?

PURPOSE

The aim of this review is to discuss the role of androgens in the progression of endometrial carcinoma (EC) with particular focus on the different kinds of androgenic hormones, androgen receptor (AR) and intracrine androgen metabolism.

METHODS

A comprehensive literature search within PubMed was performed. Selected publications related to androgens and EC were reviewed.

RESULTS

There are different kinds of androgenic hormones, and different kinds of androgens may have different effects. Elevated androgens (especially testosterone) have been associated with an increased EC risk in postmenopausal women. 5α-reductases (5α-Reds) and 17β-hydroxysteroid dehydrogenase type 2 (17βHSD2) pathway may inhibit the progression of EC mediated by dihydrotestosterone (DHT), but aromatases stimulate further progression of EC. The most of studies accessing the prognostic value of AR have found that AR expression may be a favorable prognostic indicator.

CONCLUSION

Androgens may have both oncogenic and tumor suppressive roles. Androgen-specific biases in metabolism and the expression of AR may contribute to the different prognosis of patients with EC.

Chitosan and anisodamine enhance the immersion immune efficacy of inactivated Elizabethkingia miricola vaccine in black spotted frogs

Black spotted frogs have rich nutrition and delicious meat, and its market consumption has increased year by year. However, outbreaks of the diseases have caused huge losses to the breeding industry. The crooked head disease caused by Elizabethkingia miricola (E. miricola) is highly contagious and lethal, and there is no effective treatment method. Vaccination is the most promising strategy to prevent infectious diseases. Immersion vaccination has attracted many researchers because of its simplicity of operation in preventing infectious diseases. In addition, immersion vaccines can be more effective when used with adjuvants. In this study, we prepared inactivated E. miricola with 0.3% formaldehyde, and the black spotted frogs were vaccinated by soaking in inactivated E. miricola vaccine, anisodamine + vaccine mixture, β-glucan + vaccine mixture, chitosan + vaccine mixture for 60 min. PBS was used as a control. After being challenged by E. miricola, the survival rate of anisodamine + vaccine (57%) and chitosan + vaccine group (63%) was significantly higher than that of the control group (17%). By analyzing pathological sections, we found that the chitosan + vaccine and anisodamine + vaccine groups protected the brain, eye, liver and kidney tissues of the black spotted frogs compared to the control group, which was consistent with the trend of survival rate. In addition, chitosan + vaccine and anisodamine + vaccine groups had better effects on LZM, TSOD and C3 in serum than control group. Meanwhile, the numbers of the percentage of leukocytes/haemocytes in the peripheral blood of immunized black spotted frogs increased. The anisodamine + vaccine group (5.3%) and chitosan + vaccine (5.38%) group were significantly higher than the blank control group (2.24%), which indicate that the two groups induced a more significant immune response and were more resistant to bacterial invasion. The tissue bacterial loads in liver, brain, kidney and eye were significantly lower in the anisodamine + vaccine and chitosan + vaccine groups than that of the control group. This study explored and demonstrated the good efficiency of chitosan and anisodamine as adjuvants for immunization by immersion and provided a reference for improving the efficiency of immunization by immersion.

Dietary supplementation with nanoparticle CMCS-20a enhances the resistance to GCRV infection in grass carp (Ctenopharyngodon idella)

Combination of antimicrobial proteins and nanomaterials provides a platform for the development of immunopotentiators. Oral administration of immunopotentiators can significantly enhance the immunity of organisms, which provides ideas for disease prevention. In this study, we confirmed that nanoparticles CMCS-20a can efficiently prevent grass carp reovirus (GCRV) infection. Firstly, we verified that CiCXCL20a is involved in the immune responses post GCRV challenge in vivo and alleviates the cell death post GCRV challenge in CIK cells. Then, we prepared nanoparticles CMCS-20a using carboxymethyl chitosan (CMCS) loaded with grass carp (Ctenopharyngodon idella) CXCL20a (CiCXCL20a). Meanwhile, we confirmed nanoparticles CMCS-20a can alleviate the degradation in intestine. Subsequently, we added it to the feed by low temperature vacuum drying method and high temperature spray drying method, respectively. Grass carp were oral administration for 28 days and challenged by GCRV. Low temperature vacuum drying group (LD-CMCS-20a) significantly improve grass carp survival rate, but not high temperature spray drying group (HD-CMCS-20a). To reveal the mechanisms, we investigated the serum biochemical indexes, intestinal mucus barrier, immune gene regulation and tissue damage. The complement component 3 content, lysozyme and total superoxide dismutase activities are highest in LD-CMCS-20a group. LD-CMCS-20a effectively attenuates the damage of GCRV to the number of intestinal villous goblet cells and mucin thickness. LD-CMCS-20a effectively regulates mRNA expressions of immune genes (IFN1, Mx2, Gig1 and IgM) in spleen and head kidney tissues. In addition, LD-CMCS-20a obviously alleviate tissue lesions and viral load in spleen. These results indicated that the nanoparticles CMCS-20a can enhance the disease resistance of fish by improving their immunity, which provides a new perspective for fish to prevent viral infections.

A Novel Antimicrobial Peptide Derived from Bony Fish IFN1 Exerts Potent Antimicrobial and Anti-Inflammatory Activity in Mammals

Type I interferons (IFN-Is) are critical antiviral cytokine in innate immunity but with limited direct defense ability against bacterial infections in mammals. In bony fish, despite all the IFN-Is (IFN1-4) act in antiviral immunity, studies demonstrate that IFN1 can remarkably contribute to host defense against bacterial infections. In this study, we found that IFN1 from grass carp (Ctenopharyngodon idella) contains an unusual cationic and amphipathic α-helical region (named as gcIFN-20, sequence: SYEKKINRHFKILKKNLKKK). The synthesized peptide gcIFN-20 could form α-helical structure in a membrane environment and exerts potent antimicrobial activity against multiple species of Gram-negative (G-) and Gram-positive (G+) bacteria with negligible toxicity. Mechanism studies showed gcIFN-20 kills G+ bacteria through membrane disruption and cytoplasm outflow while G- bacteria through membrane permeation and protein synthesis inhibition. In two mouse bacterial infection models, gcIFN-20 therapy could significantly reduce tissue bacterial loads and mortalities. In addition to the direct antibacterial activity, we also found that gcIFN-20 could significantly suppress the lipopolysaccharide (LPS)-induced pro-inflammatory cytokines in vitro and in vivo, obviously alleviated lung lesions in a mouse endotoxemia model. The mechanism is that gcIFN-20 interacts with LPS, causes LPS aggregation and neutralization. The antimicrobial and anti-inflammatory activities in vivo of gcIFN-20 in mammalian models suggested a promising agent for developing peptide-based antibacterial therapy. IMPORTANCE Type I interferons play crucial role in antiviral immunity in both vertebrates and invertebrates. The powerful antimicrobial activity is recently reported in nonmammalian vertebrates. The present study identified a novel antimicrobial peptide (gcIFN-20) derived from grass carp interferon 1, found gcIFN-20 exhibits forceful bactericidal and anti-inflammatory activity in mammals, and efficient therapeutic effect against two clinical severe extraintestinal pathogenic Escherichia coli and a mouse endotoxemia models. The antimicrobial mechanisms are membrane disruption and cytoplasm overflow for Gram-positive bacteria, while membrane permeation and protein synthesis inhibition for Gram-negative bacteria. The anti-inflammatory mechanisms can be aggregating and neutralizing lipopolysaccharide to attenuate the binding with receptors and facilitate phagocytosis. The results indicate that gcIFN-20 can be a promising novel therapeutic agent for bacterial diseases and inflammatory disorders, especially as a potential weapon for multidrug resistant strain infections.

An Oral Microencapsulated Vaccine Loaded by Sodium Alginate Effectively Enhances Protection Against GCRV Infection in Grass Carp (Ctenopharyngodon idella)

Grass carp reovirus (GCRV) is highly infectious and lethal to grass carp, causing huge economic losses to the aquaculture industry annually. Currently, vaccination is the most effective method against viral infections. Among the various vaccination methods, the oral vaccination is an ideal way in aquaculture. However, low protective efficiency is the major problem for oral vaccination owing to some reasons, such as antigen degradation and low immunogenicity. In our study, we screened the antigenic epitopes of GCRV-II and prepared an oral microencapsulated vaccine using sodium alginate (SA) as a carrier and flagellin B (FlaB) as an adjuvant, and evaluated its protective effects against GCRV-II infection in grass carp. The full length and three potential antigenic epitope regions of GCRV-II VP56 gene were expressed in Escherichia coli and purified by glutathione affinity column respectively. The optimal antigen (VP56-3) was screened by enzyme-linked immunosorbent assay (ELISA). Adjuvant FlaB was also expressed in E. coli and purified by Ni2+ affinity column. Subsequently, we prepared the oral vaccines using sodium alginate as a carrier. The vaccine (SA-VP56-3/FlaB) forms microsphere (1.24 ± 0.22 μm), examined by transmission electron microscopy, scanning electron microscopy, and dynamic light scattering assay. SA-VP56-3/FlaB vaccine has excellent stability, slow-release, and low toxicity by dynamic light scattering assay, release dynamic assay, in vivo fluorescence imaging system, hemolytic activity and cytotoxicity. Then we vaccinated grass carp orally with SA-VP56-3/FlaB and measured immune-related parameters (serum neutralizing antibody titer, serum enzyme activity (TSOD, LZM, C3), immune-related genes ((IgM, IFN1, MHC-II, CD8 in head kidney and spleen), IgZ in hindgut)). The results showed that SA-VP56-3/FlaB significantly induced strong immune responses, compared to other groups. The highest survival rate achieved in SA-VP56-3/FlaB microencapsulated vaccine (56%) in 2 weeks post GCRV challenge, while 10% for the control group. Meanwhile, the tissue virus load in survival grass carp is lowest in SA-VP56-3/FlaB group. These results indicated that SA-VP56-3/FlaB could be a candidate oral vaccine against GCRV-II infection in aquaculture.

Oral Administration of Nanopeptide CMCS-20H Conspicuously Boosts Immunity and Precautionary Effect Against Bacterial Infection in Fish

Massive mortalities caused by bacterial infections in intensive aquaculture result in serious economic losses. In this study, a novel antimicrobial peptide gcIFN-20H was efficiently expressed in Pichia pastoris (GS115) and loaded on carboxylmethyl chitosan (CMCS) to prepare CMCS-20H nanoparticles. Through physical characterization assays (TEM, DLS, BCA, and Raman) and biological activity tests (antimicrobial activity and cytotoxicity), CMCS-20H nanopeptide was verified to be spherical nanoparticles with sustained release, antimicrobial activity, and negligible toxicity. CMCS-20H nanoparticles are more resistant to intestinal degradation than unloaded gcIFN-20H by indirect immunofluorescence assay. Oral administration was then carried out for 42 days. Complement C3 content, lysozyme, and total superoxide dismutase activities are highest in CMCS-20H group by serum biochemistry index assays. After challenge with Aeromonas hydrophila, the survival rate in CMCS-20H group is highest (46%), which is 64% higher than the control group (28%). Meanwhile, the tissue bacterial loads (intestine, spleen, head kidney, trunk kidney, hepatopancreas, muscle, and blood) in the CMCS-20H group are significantly lower than other groups. By PAS staining analysis, the number of intestinal villi goblet cells and the thickness of mucin in the CMCS-20H group obviously increased. CMCS-20H effectively enhances mRNA expressions of some important immune genes (IL-1β, IL-6, TNF-α, IL-2, IFN-γ2, and IgM). The minimal tissue lesions (Intestine, spleen, and trunk kidney) were seen in the CMCS-20H group by histopathological examination. 16S rRNA sequencing showed that oral CMCS-20H maintains the intestinal microbiome homeostasis in bacterial infection. The results indicate that the novel nanopeptide CMCS-20H as the immunopotentiator can remarkably boost fish immunity and precautionary effect by oral administration and address the theoretical mechanisms and insights into the promising application prospect in aquaculture.

Oral Administration of Bacillus subtilis Subunit Vaccine Significantly Enhances the Immune Protection of Grass Carp against GCRV-II Infection

Grass carp reovirus (GCRV) is a severe virus that causes great losses to grass carp culture every year, and GCRV-II is the current popular and fatal strain. VP56, fibrin on the outer surface of GCRV-II, mediates cell attachment. In this study, we firstly divided the VP56 gene into four fragments to screen the optimal antigen by enzyme-linked immunosorbent assay and neutralizing antibody methods. The second fragment VP56-2 demonstrates the optimal efficiency and was employed as an antigen in the following experiments. Bacillus subtilis were used as a carrier, and VP56-2 was expressed on the surface of the spores. Then, we performed the oral immunization for grass carp and the challenge with GCRV-II. The survival rate was remarkably raised, and mRNA expressions of IgM were significantly up-regulated in spleen and head kidney tissues in the B. s-CotC-VP56-2 group. Three crucial immune indexes (complement C3, lysozyme and total superoxide dismutase) in the sera were also significantly enhanced. mRNA expressions of four important genes (TNF-α, IL-1β, IFN1 and MHC-II) were significantly strengthened. Tissue lesions were obviously attenuated by histopathological slide examination in trunk kidney and spleen tissues. Tissue viral burdens were significantly reduced post-viral challenge. These results indicated that the oral recombinant B. subtilis VP56-2 subunit vaccine is effective for controlling GCRV infection and provides a feasible strategy for the control of fish virus diseases.

Pattern and predictors of one-year mortality in heart failure: China PEACE Prospective Heart Failure Study

Background

Heart failure (HF) is a global public health problem, which causes high mortality.

Purpose

To characterize the pattern of 1-year mortality, including the rate and timing of death, and to identify clinical and non-clinical factors predicting 1-year all-cause mortality after hospitalization for HF.

Methods

We prospectively enrolled patients who were hospitalized primarily for HF and discharged alive from 52 hospitals across 20 provinces in China between August 2016 and May 2018, and followed them up by face-to-face interview or telephone. Patients' fatal status were ascertained according to investigators' report and national death registration. Cognitive function was measured by Mini-Cog score and health status was measured by Kansas City Cardiomyopathy Questionnaire (KCCQ). We fitted a Cox proportional hazards model accounting for hospital as random effects to identify patient characteristics associated with 1-year all-cause mortality.

Results

Among 4899 patients, 4882 (97.7%) completed 1-year follow-up. The median (IQR) age was 67 (57, 75) years and 37.5% were women. The main etiology of HF was ischemic heart disease (53.1%), 66.0% of patients had history of HF before the index hospitalization. Among 813 deaths within one year after discharge, 13.4% and 58.4% occurred within one months and six months, respectively. Systolic blood pressure <100mmHg at admission (hazard ratio [HR] 2.33, 95% CI 1.76–3.08), NYHA class IV (HR 1.37, 95% CI 1.1–1.7), anemia (HR 1.3, 95% CI 1.1–1.54), hs-cTNT≥18 ng/L (HR 1.84, 95% CI 1.53–2.22), hyponatremia (HR 1.66, 95% CI 1.38–1.98), LVEF<40% (HR 1.25, 95% CI 1.02–1.53), QRS interval≥120mms (HR 1.19, 95% CI 1.02–1.4), Cognitive impairment (HR 1.25, 95% CI 1.07–1.46) and low KCCQ score (HR 1.24 per 25 score decrease, 95% CI 1.11–1.39) were associated with higher risks of 1-year all-cause mortality. In contrast, female (HR 0.83, 0.7–0.99), sleep apnea syndrome (HR 0.55, 95% CI 0.35–0.88) were associated with lower risks of 1-year all-cause mortality.

Conclusion

In China, one in six patients hospitalized for HF die within 1-year, with the majority occurring during the first 6 months after hospital discharge. Both clinical and non-clinical factors predict 1-year mortality.

Funding Acknowledgement

Type of funding source: Other. Main funding source(s): The National Key Research and Development Program from the Ministry of Science and Technology of China; the CAMS Innovation Fund for Medical Science; the 111 Project from the Ministry of Education of China

The Combination of Molecular Adjuvant CCL35.2 and DNA Vaccine Significantly Enhances the Immune Protection of Carassius auratus gibelio against CyHV-2 Infection

Cyprinid herpesvirus 2 (CyHV-2) infection results in huge economic losses in gibel carp (Carassius auratus gibelio) industry. In this study, we first constructed recombinant plasmids pcORF25 and pcCCL35.2 as DNA vaccine and molecular adjuvant against CyHV-2, respectively, and confirmed that both recombinant plasmids could be effectively expressed in vitro and in vivo. Then, the vaccination and infection experiments (n = 50) were set as seven groups. The survival rate (70%) in ORF25/CCL35.2 group was highest. The highest specific antibody levels were found in ORF25/CCL35.2 group in major immune tissues by qRT-PCR, and confirmed in serum by ELISA assay, antibody neutralization titer, and serum incubation-infection experiments. Three crucial innate immune indices, namely C3 content, lysozyme, and total superoxide dismutase (TSOD) activities, were highest in ORF25/CCL35.2 group in serum. pcORF25/pcCCL35.2 can effectively up-regulate mRNA expressions of some important immune genes (IL-1β, IL-2, IFN-γ2, and viperin), and significantly suppress CyHV-2 replication in head kidney and spleen tissues. The minimal tissue lesions can be seen in ORF25/CCL35.2 group in gill, spleen, and trunk kidney tissues by histopathological examination. The results indicated that the combination of DNA vaccine pcORF25 and molecular adjuvant pcCCL35.2 is an effective method against CyHV-2 infection, suggesting a feasible strategy for the control of fish viral diseases.

β-glucan and anisodamine can enhance the immersion immune efficacy of inactivated cyprinid herpesvirus 2 vaccine in Carassius auratus gibelio

As one of the most important fish in freshwater aquaculture, gibel carp (Carassius auratus gibelio) is easily susceptible to Cyprinid herpesvirus 2 (CyHV-2). Immersion vaccination has attracted many researchers due to its simple operation in preventing infectious diseases. However, the unavoidable disadvantage is that the immersion vaccine must be used with adjuvants to get a better performance. In this study, gibel carps were vaccinated by a 60 min bath in a β-propiolactone-inactivated Cyprinid herpesvirus 2, mixed with DTT, β-glucan, anisodamine and scopolamine, respectively. After immunization, the fishs were challenged by CyHV-2 in 2 weeks. By analyzing pathological section, we found that β-glucan, anisodamine and scopolamine groups protected the gibel carp compared to the control group, which was consistent with the trend of survival rate. Specifically, β-glucan group in serum appeared best on lysozyme, TSOD and complement C3. Real time quantitative RT-PCR results demonstrated that in both spleen and head kidney tissues, mRNA expressions of typical Th1 immune response cytokines IL-2 and IFN-γ2 in β-glucan group and anisodamine group were significantly higher than other groups and the level of immunoglobulins related to systemic immunity (IgM) and mucosal immunity (IgZ) were also enhanced in the immune period. DTT group slightly affected immune gene and serum enzyme activity, while did not show an adjuvant effect on survival rate. In addition, four adjuvant groups could obviously inhibit CyHV-2 replication. This study explored and proved the good efficiency of β-glucan or anisodamine as immersion immune adjuvant and also provided reference for improving the efficiency of immersion immunity.

Tunable Electrorheological Fluid Microfluidic Rectifier: Irreversibility of Viscous Flow Due to Spatial Asymmetry Induced Memory Effects

Because of the reversibility of viscous flow it is not expected to obtain a fluidic rectifier simply from geometrical asymmetry without any moving mechanical parts. Here, we found a counterexample by using spatial asymmetry combined with an electric field to inject memory effects that render the flow irreversible. This stems from the strong dependency of the electrorheological fluid particle chaining on the flow direction. A funnel-shaped microfluidic rectifier with electrorheological fluid has been shown to be easily and rapidly tuned via the applied electric field to achieve an almost order of magnitude rectification along with pressure oscillations. These findings are of importance for the realization of fluidic diodes, rectifiers, and ratchets.

Significant enhancement of the electrorheological effect by non-straight electrode geometry

In contrast to the commonly used straight electrodes with electrorheological (ER) fluid, here, we studied the effect of non-straight electrodes comprising the sides of a microchannel, on the ER fluid response. A more than one order of magnitude enhancement of the apparent viscosity was observed for non-straight electrode geometries, where castellated and sawtooth electrode geometries were used merely as an example, relative to that measured for straight electrodes. The enhancement increased with increasing applied voltage and exhibited a distinct maximum in the frequency range of 5-10 Hz. Experimental analyses demonstrated that positive dielectrophoresis-driven attraction of the chain ends to the sharp tips of the electrode underlies the ER enhancement. Hence, introducing such uniformity breakage of the electric field through non-straight electrode geometries is of practical importance for enhancement of the ER response.

[Impact of informal e-waste recycling on human health]

Increasing e-waste has become a major problem for global environment and public health. In the process of dismantling and recycling of disordered electronic waste, heavy metals such as lead and brominated flame retardants and organic substances are released into environmental media such as air, soil, dust and water, which is harmful to the health of local residents. Taking an e-waste dismantling area in Guangdong Province as an example, this paper reviews exposure levels of heavy metals and organic matters in e-waste recycling areas in China, as well as the health effects of local residents. Previous studies have found that e-waste recycling activities led to serious environmental pollution and high exposure levels of heavy metals and organic matters in local residents, which has a certain impact on the physiological functions of various human systems. The establishment of a centralized dismantling zone can effectively reduce the load level of various pollutants.

[The study of exposure levels of dioxin-like compounds in cord blood of newborns in an e-waste dismantling area in Guangdong Province]

Objective: To study the pollution status of polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCB), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in cord blood of newborns in an e-waste dismantling area of Guangdong Province. Methods: We recruited 20 eligible mothers and newborns who could meet the inclusion criteria in local hospitals of Guiyu in 2007. The inclusion criteria included directly engaged in dismantling e-waste during pregnancy and within 1 year before pregnancy; living in the e-waste dismantling workshops or the distance between living place and the e-waste dismantling areas was ≤200 m; the father of newborn was directly engaged in electronic waste dismantling for more than 1 year; the frequency of visiting the e-waste dismantling workshop during pregnancy was ≥3 times in a week. Questionnaires and physical examinations were performed on maternal and neonatal, and cord blood was collected from newborns to detect PCDD/Fs, PCB and PBDE. The concentration level of organic pollutants was corrected by the blood lipid content, and the total toxicity equivalent was calculated. The correlation between three compounds was analyzed by Spearman correlation. Results: The mothers of the 20 newborns were (23.45±3.27) years old and lived for more than 5 years. The number of one parent engaged in e-waste dismantling, the mother or father smoking, and parent engaged in e-waste dismantling work were 3, 13, 15 and 19, respectively. The weight of newborns ranged from 2.5 to 3.6 kilogram and the Apgar score was 10 points. No adverse birth outcomes such as preterm birth, malformation or stillbirth were found. The median (maximum, minimum) concentration of PCBs, PCDD/Fs and PBDEs in cord blood were 263.22 (328.29, 244.19), 38.42 (147.49, 12.68), 39.33 (265.11, 14.81) pg/g lipid, respectively. The median (maximum, minimum) of toxic equivalence concentrations of PCDD/Fs and PCB were 3.94 (9.24, 2.69) and 15.95 (26.64, 9.28) pg TEQ/g lipid. PBDE, the proportion of PBDE, PCB and PCDD/Fs in cord blood was 50.41%, 49.25% and 0.34%, respectively. PCBs and PBDEs were positively correlated (r=0.733, P=0.039). Conclusion: The high concentrations of PCDD/Fs, PCB, and PBDE were detected in the e-waste dismantling area. It is recommended that the risk of such substances on the health of local people should be assessed in a timely manner.

[Surveillance on the epidemiological and etiological characteristics of hand-foot-mouth disease during the outbreaks in three cities of Jiangsu province, 2012-2015]

Objective: To analyze the epidemiological and etiological characteristics through monitoring the outbreaks of hand-foot-mouth disease (HFMD), in three cities of Jiangsu province from 2012 to 2015 and to provide evidence for prevention and control of the disease. Methods: Data related to cases of HFMD during the outbreaks was collected through active surveillance programs in three cities of Jiangsu province, under the guidelines of clusters and outbreaks of HFMD (2012 edition HFMD). Features related to clusters and outbreaks of the disease were identified according to the real-time RT-PCR detection. Descriptive analysis was conducted to understand the type/subtype of HFMD virus and time, area, place and extent of the outbreaks. Logistic regression was used to explore the influencing factors. Results: From 2012 to 2015, a total of 1 425 HFMD epidemics, including 1 314 clusters and 111 outbreaks were reported. Two incidence peaks were observed each year, between March and June, as well as between September and December, accounting for 58.18% (829/1 425), 33.68% (480/1 425), respectively. Most HFMD clusters and outbreaks were reported in Wuxi city, accounting for 59.30% (845/1 425) of the total. Most HFMD clusters and outbreaks happened in kindergartens, accounting for 68.63% (978/1 425) of the total. A total of 931 HFMD clusters and outbreaks were confirmed under laboratory findings. The main pathogens were Entervirus type 71 (EV71) in 2013 and Coxsackie A16 (Cox A16) in 2015, respectively, while both EV71 and Cox A16 were predominant in 2012 and 2014. With multivariate backward conditional regression, surrounding environment was identified as important risk factor associated with the attack rate. Health condition of the environment was quite good, with low attack rates (middle vs. bad: OR=0.150, 95% CI: 0.034-0.667; good vs. bad: OR=0.072, 95%CI: 0.016-0.317). Time between the onset of index patient and the reporting of HFMD clusters or outbreaks was important in the control program of HFMD epidemics (4-7 d vs. 1-3 d: OR=3.452, 95%CI: 2.293-5.198; 8 d vs. 1-3 d: OR=12.108, 95%CI: 7.767-18.763). Conclusions: The clusters and outbreaks of HFMD happened in Jiangsu province showed an obvious feature of seasonality. The predominant types or subtypes of the virus varied in different years. Kindergartens were the hard-hit places of HFMD clusters and outbreaks. Timely report of the disease appeared the key point regarding the control of HFMD clusters and outbreaks.

Decreased epithelial and plasma miR-181b-5p expression associates with airway eosinophilic inflammation in asthma

BACKGROUND

Airway eosinophilic inflammation is a pivotal feature of asthma. Epithelial cells play critical roles in airway eosinophilia. We hypothesized that epithelial microRNAs (miRNAs) are involved in airway eosinophilia.

OBJECTIVE

This study investigated the associations between epithelial and plasma miR-181b-5p and airway eosinophilic inflammation, and the possible mechanism by which miR-181b-5p participates in eosinophilic inflammation.

METHODS

Epithelial miRNAs expression was profiled by miRNA array in eight subjects with asthma and four healthy controls. Epithelial miR-181b-5p expression was confirmed by quantitative PCR in the subjects for array experiment and another cohort including 21 subjects with asthma and 10 controls. Plasma miR-181b-5p was determined by quantitative PCR in 72 subjects with asthma and 35 controls. Correlation assays between epithelial and plasma miR-181b-5p expression and airway eosinophilia were performed. The target of miR-181b-5p, SPP1, was predicted by online algorithms and verified in BEAS-2B cells. The role of miR-181b-5p in epithelial proinflammatory cytokine expression was examined in an in vitro system.

RESULTS

Epithelial miR-181b-5p expression was decreased in subjects with asthma. Epithelial miR-181b-5p levels were inversely correlated with sputum and bronchial submucosal eosinophilia. Plasma miR-181b-5p was decreased and correlated with epithelial miR-181b-5p in subjects with asthma. There was a strong inverse correlation between plasma miR-181b-5p and airway eosinophilia in subjects with asthma. Plasma miR-181b-5p was increased after inhaled corticosteroids treatment. We verified that SPP1 is a target of miR-181b-5p. In human bronchial epithelial cells, miR-181b-5p regulated IL-13-induced IL-1β and CCL11 expression by targeting SPP1. Dexamethasone restored IL-13-induced miR-181b-5p down-regulation and suppressed IL-13-induced SPP1, IL-1β and CCL11 expression.

CONCLUSIONS AND CLINICAL RELEVANCE

Epithelial and plasma miR-181b-5p are potential biomarkers for airway eosinophilia in asthma. MiR-181b-5p may participate in eosinophilic airway inflammation by regulating proinflammatory cytokines expression via targeting SPP1.

Hypoxia upregulates Rab11-family interacting protein 4 through HIF-1α to promote the metastasis of hepatocellular carcinoma

Hypoxic microenvironment is a powerful driving force for the invasion and metastasis of hepatocellular carcinoma (HCC). Hypoxia-inducible factor 1α (HIF-1α), as a crucial regulator of transcriptional responses to hypoxia, induces the expression of multiple target genes involved in different steps of HCC metastatic process. It is critical to find target genes associated with metastasis under hypoxia for shedding new light on molecular mechanism of HCC metastasis. In this study, we uncovered that hypoxia could induce the upregulation of Rab11-family interacting protein 4 (Rab11-FIP4) and activation of Rab11-FIP4 promoter by HIF-1α. The overexpression of Rab11-FIP4 significantly enhanced the mobility and invasiveness of HCC cells in vitro, also contributed to distant lung metastasis in vivo, whereas silencing of Rab11-FIP4 decreased the ability of migration and invasion in HCC cells in vitro and suppressed lung metastasis in vivo. Rab11-FIP4 facilitated HCC metastasis through the phosphorylation of PRAS40, which was regulated by mTOR. Furthermore, the expression level of Rab11-FIP4 was significantly increased in HCC tissues and high expression of Rab11-FIP4 was closely correlated with vascular invasion and poor prognosis in HCC patients. A markedly positive correlation between the expression of Rab11-FIP4 and HIF-1α was observed in HCC tissues and combination of Rab11-FIP4 and HIF-1α was a more valuable predictor of poor prognosis for HCC patients. In conclusion, Rab11-FIP4 is a target gene of HIF-1α and has a pro-metastatic role in HCC, suggesting that Rab11-FIP4 may be a promising candidate target for HCC treatment.

The FUS1 gene inhibits EC109 cell growth mediated by a lentivirus vector

The effects of the FUS1 gene on the oesophageal carcinoma cell line EC109 are investigated. The messenger RNA (mRNA) expression level of the FUS1 gene was detected by a reverse transcription polymerase chain reaction (RT-PCR) technique in the cell lines SHEE, SHEEC and EC109. The full length of the FUS1 gene was amplified using a PCR technique from the total RNA of umbilical mesenchymal stem cells. The FUS1 gene was cloned into a pSL6-IRES-EGFP vector and identified by PCR, digestion and sequencing. The recombinant pSL6-FUS1-IRES-EGFP plasmid was transfected into 293FT cells and the resulting lentivirus was collected. The growth of EC109 cells after transfection with lentivirus containing the FUS1 gene was determined by MTT assay and plate colony formation. Expression of the FUS1 gene in EC109 cells was weaker than that in SHEE, SHEEC cells and human umbilical vein endothelial cells (HUVEE; used as a control). Transfection efficiency was more than 80% after 48 h. Cell growth assessed by MTT assay was inhibited by about 40% compared with the control group; a finding that was in accordance with the plate colony formation results. The results suggest that the FUS1 gene might be a candidate tumour suppressor gene for the treatment of oesophageal carcinoma; however, these results require confirmation in in vivo studies.

Effect of WT1 antisense mRNA on the induction of apoptosis in ovarian carcinoma SKOV3 cells

PURPOSE

To study the effect of WT1 antisense oligodeoxynucleotide (ASODN) transfection on the proliferation and apoptosis of SKOV3 cells.

METHODS

There were four groups in our study: normal control group, WT1 ASODN group, WT1 SODN group and lipofectamine group. Cell apoptosis was observed by flow cytometry. The effect of WT1 ASODN on cell proliferation was assayed by the MTT method. RT-PCR and Western blot were used to detect the expression level of WT1 mRNA and protein.

RESULTS

The growth of the ovarian cancer cell line SKOV3 became significantly slower and its activity was reduced after being transfected by WT1 ASODN, with the inhibition rate of 49.48%. WT1 antisense phosphorothioate oligonucleotides did not only inhibit cell proliferation, arrest cell cycle at G0-G1 checkpoint and induce apoptosis in SKOV3 ovarian carcinoma cells, but also downregulated WT1 mRNA and protein expression, which contributed to the apoptosis (p < 0.05).

CONCLUSION

WT1 antisense phosphorothioate oligonucleotides could both inhibit the proliferation and induce the apoptosis in SKOV3 ovarin carcinoma cell lines. Antisense oligonucleotides of WT1 may potentially help with the gene therapy of ovarian carcinoma.

Musclin Inhibits Insulin Activation of Akt/Protein Kinase B in Rat Skeletal Muscle

Musclin is a muscle-derived secretory peptide that induces insulin resistance in vitro We studied the effect of musclin (0.5 μg/ml) on insulin-stimulated glucose uptake in rat skeletal muscles and also the effect of rosiglitazone (0.4 μg/ml). Pre-incubation of muscles with musclin resulted in decreased insulin-stimulated glucose uptake. Musclin also reduced expression of peroxisome proliferator-activated receptor γ (PPARγ) and liver X receptor α (LXRα) mRNAs, although expression of glucose transporter 4 mRNA was unaltered. Rosiglitazone attenuated the effects of musclin on glucose uptake and PPARγ and LXRα mRNA expression. Western blotting demonstrated that activation of protein kinase B (Akt/PKB) in the insulin-signalling cascade was decreased by musclin but corrected by rosiglitazone. These findings suggest that musclin-induced impairment of insulin-stimulated glucose uptake in skeletal muscle is related to Akt/PKB inhibition and might be modulated by PPARγ/LXRα.

Investigation of the PARK10 Gene in Parkinson Disease

Two recent association mapping studies in Parkinson disease (PD) reported three candidate genes for the PARK10 locus: EIF2B3 as a modifier of age-at-onset of PD (min P= 0.0004) and HIVEP3 as a PD risk gene (P < or = 0.006) (Oliveira et al. 2005); and LOC200008 (CDCP2) identified by the whole genome association (WGA) study of PD of Maraganore et al. (2005). However, evaluation of the on-line PD WGA results revealed two significant SNPs in HIVEP3 in the two datasets, Tier 1 and Tier 2, used by Maraganore et al. (P < or = 0.008 for Tier 1 and P=0.03 for Tier 2 dataset). Here, we revisited both the HIVEP3 and CDCP2 loci by examining 47 SNPs, mostly tagging, in an expanded PD family dataset (293 multiplex and 467 singleton families). A discordant sibpair (DSP) dataset (one DSP per family), with similar data structure as the WGA Tier 1 dataset, was also tested. We confirmed our and other previous negative findings for CDCP2. However, five significant SNPs in HIVEP3 (min P=0.004) were observed, although the two significant HIVEP3 SNPs from the PD WGA study were not significant in our datasets. Even though the sets of significant HIVEP3 markers differ between studies, these findings strongly support HIVEP3 as a candidate for PARK10. Further testing of HIVEP3 by other groups is encouraged.

Relationship between HPV16/18 E6 and 53, 21WAF1, MDM2, Ki67 and cyclin D1 expression in esophageal squamous cell carcinoma: comparative study by using tissue microarray technology

AIM

To investigate the role of human papillomavirus (HPV) HPV16/18 E6 oncogene in the carcinogenesis of esophageal cell carcinoma (ESCC).

MATERIALS AND METHODS

Tissue microarray (TMA) block was constructed from 60 cases of paraffin-embedded ESCC tissues and pair-matched controls (adjacent normal epithelium). Immunohistochemistry (IHC) methods were applied to detect the expression of HPV16/18 E6, p53, p21(WAF1), MDM2, Ki67 and cyclin D1 proteins on TMA slides. In situ hybridization (ISH) targeting HPV gene was also used.

RESULTS

In ESCC samples, 18.3% (11/60) were revealed HPV16/18 E6 positive by IHC, while 40.0% (24/60) HPV positive by ISH; HPV16/18 E6 expression was significantly higher than that of control samples. In ESCC samples, the expressions of p53, p21(WAF1), Cyclin D1, MDM2 and Ki67 were recorded in 60.0% (36/60), 40.0% (24/60), 51.7% (31/60), 65.0% (39/60) and 88.3% (53/60) cases respectively, In ESCC samples, p53, MDM2 and Ki67 expression correlated with the HPV16/18 E6 expression (p less, similar 0.01), p21(WAF1) expression - with these of MDM2 and cyclin D1 (p less, similar 0.01) whilst expression of Ki67 - with ESCC grade (p less, similar 0.01).

CONCLUSION

HPV might be one of etiological factor of esophageal carcinoma in Shantou, China. p53, MDM2 proteins may play important roles in the pathogenesis of HPV-associated ESCC.

Ultrastructural observation on the transformation of the spermatozoon in spermatogenesis of Taeniid cestodes

AIM

To study the transformation of taeniid spermatozoon during spermatogenesis on the ultrastructure level.

METHODS

Transmission electronmicroscopy.

RESULTS

This paper was the second part of the ultrastructural observations on the spermatogenesis in Taeniid cestodes: The transformation of the spermatozoon. The 64-spermatid-plasmodium was generated from the secondary meiosis of the 32 rose-like secondary spermatocytes. The transformation of the spermatozoon was a complex process. Firstly, both the cytoplasm and nucleus of the spermatid elongated while the cytoplasm increased and connected to the cytoplasmic mass (cytophore). Secondly, the chromatins of nucleus polymerized to a thread-bundle-like structure. Finally, it detached from the cytoplasm mass and became a mature spermatozoon. The mature spermatozoon was a thread-like structure, about 16.2-18.6 microns in length and 0.35-0.45 micron in diameter. There were two structurally distinct parts: the part with the nucleus was the head and the part without the nucleus was the tail. The head measured about 5-6 microns in length, 1/3 of the total body length and contained an elongated nucleus which twined around the axoneme without mitochondria. The tail was about 11.2-16.6 microns in length. Throughout the core of the tail was an axoneme with typical "9 + 1" structure. The anterior of the tail, just behind the head, were some mitochondria, about 1.6-1.7 microns in total length which twined around the axoneme. The posterior of the tail contained only an axoneme. In cross-section of the spermatozoon, about 46 microtubules were beneath the plasma membrane.

CONCLUSION

The transformation of the spermatozoon is a very complex process.

Structure of the dimerized hormone-binding domain of a guanylyl-cyclase-coupled receptor

The atrial natriuretic peptide (ANP) hormone is secreted by the heart in response to an increase in blood pressure. ANP exhibits several potent anti-hypertensive actions in the kidney, adrenal gland and vascular system. These actions are induced by hormone binding extracellularly to the ANP receptor, thereby activating its intracellular guanylyl cyclase domain for the production of cyclic GMP. Here we present the crystal structure of the glycosylated dimerized hormone-binding domain of the ANP receptor at 2.0-A resolution. The monomer comprises two interconnected subdomains, each encompassing a central beta-sheet flanked by alpha-helices, and exhibits the type I periplasmic binding protein fold. Dimerization is mediated by the juxtaposition of four parallel helices, arranged two by two, which brings the two protruding carboxy termini into close relative proximity. From affinity labelling and mutagenesis studies, the ANP-binding site maps to the side of the dimer crevice and extends to near the dimer interface. A conserved chloride-binding site is located in the membrane distal domain, and we found that hormone binding is chloride dependent. These studies suggest mechanisms for hormone activation and the allostery of the ANP receptor.

Ligand binding-dependent limited proteolysis of the atrial natriuretic peptide receptor: juxtamembrane hinge structure essential for transmembrane signal transduction

The atrial natriuretic peptide (ANP) receptor is a 130-kDa transmembrane protein containing an extracellular ANP-binding domain, a single transmembrane sequence, an intracellular kinase-homologous domain, and a guanylate cyclase (GCase) domain. We observed that the receptor, when bound with ANP, was rapidly cleaved by endogenous or exogenously added protease to yield a 65-kDa ANP-binding fragment. No cleavage occurred without bound ANP. This ligand-induced cleavage abolished GCase activation by ANP. Cleavage occurred in an extracellular, juxtamembrane region containing six closely spaced Pro residues and a disulfide bond. Such structural features are shared among the A-type and B-type ANP receptors but not by ANP clearance receptors. The potential role of the hinge structure was examined by mutagenesis experiments. Mutation of Pro(417), but not other Pro residues, to Ala abolished GCase activation by ANP. Elimination of the disulfide bond by Cys to Ser mutations yielded a constitutively active receptor. Pro(417), and Cys(423) and Cys(432) forming the disulfide bond are strictly conserved among GCase-coupled receptors, while other residues are largely variable. The conserved Pro(417) and the disulfide bond may represent a consensus signaling motif in the juxtamembrane hinge structure that undergoes a marked conformational change upon ligand binding and apparently mediates transmembrane signal transduction.

[Determination of thebaine in various tissues of papaver bracteatum by gas chromatography]

Papaver bracteatum is an important source of opiates because of its high thebaine content. An efficient and convenient method of determining thebaine, not only in the root, but in the more highly pigmented capsule, stem and leaf, is urgently required. We decided to examine these in detail on a wide variety of plant material and to choose an assay method which is convenient and gives reproducible results. A simple method for the quantitative extraction and analysis of thebaine in the different tissues (capsule, root, leaf and stem) of papaver bracteatum has been established. The powdered materials were extracted with methanol under ultrasonic condition. The procedure of extraction is simple, rapid and reliable. The assay method gave satisfactory reproducibility for a wide range of plant materials (coefficient of variation 2.9% to 5.4%). The linear range of response of thebaine was from 5.0 to 500.0 mg/L. The minimum limit of detection was 2 ng. The operating time of the assay is about 20 min. The presence of other alkaloids did not interfere with the assay reported here in.

[Primary ileocecal lymphoma: report of 30 cases]

OBJECTIVE

To investigate the best therapeutic method for primary ileocecal non-Hodgkin's lymphoma.

METHOD

Clinicopathologic features of 30 patients who had been treated from June 1964 to September 1993 were analyzed retrospectively.

RESULT

Twenty-eight patients (93%) underwent resection of their disease. Eleven patients had the resection followed by chemotherapy. Eleven patients had the resection followed by chemotherapy and radiotherapy. All had pathologic evidence. Twenty-nine patients were categorized as B-cell type NHL. One had T-cell lesion. Eleven patients had stage I disease, 11 stage II, 4 stage III, and 4 stage IV. The 5-year survival rate was 36.67%.

CONCLUSION

The prognostic factors are stage of the disease and treatment modality. Adequate initial surgery combined with radiotherapy and chemotherapy may provide optimum therapy for patients with primary ileocecal lymphoma.

Ultrastructural observation on spermatocytogenesis in Taeniid cestodes

AIM

To study the spermatocytogenesis of taeniid cestodes at the ultrastructural leaves.

METHODS

Transmission electron microscopy.

RESULTS

The ultrastructural observation on spermatocytogenesis in Taenia solium, T. saginata and T. pisiformis were made by TEM. Two types of spermatogonia; type A and B, as well as the supporting cells surrounding the peripheral of spermatogonia are recognized. The type A spermatogonia are stem cells and the type B are mother cells which produce 16 primary spermatocytes by mitosis for 4 times with the cells unseparated. The primary spermatocytes are characterized by the ribosome masses in the cytoplasm. 32 secondary spermatocytes arranged in roselike were produced by reductive division of primary spermatocytes. The secondary spermatocytes become the spermatid quickly by short time development.

CONCLUSION

The dividing mode of spermatogonia in Taeniid cestodes is mitosis with cells unseparated.

Substrate specificity and identification of functional groups of homoserine kinase from Escherichia coli

Homoserine kinase, an enzyme in the aspartate pathway of amino acid biosynthesis in Escherichia coli, catalyzes the conversion of L-homoserine to L-homoserine phosphate. This enzyme has been found to have broad substrate specificity, including the phosphorylation of L-homoserine analogs where the carboxyl functional group at the alpha-position has been replaced by an ester or by a hydroxymethyl group. Previous pH profile studies [Huo. X., & Viola, R. E. (1996) Arch. Biochem. Biophys. 330, 373-379] and chemical modification studies have suggested the involvement of histidinyl, lysyl, and argininyl residues in the catalytic activity of the enzyme. With the assistance of sequence alignments, several potential amino acids have been targeted for examination. Site-directed mutagenesis studies have confirmed a role for arginine-234 in the binding of the carboxyl group of L-homoserine, and the involvement of two histidine at the homoserine binding site. Mutations at these sites have led to the decoupling of the kinase activity from an inherent ATPase activity in the enzyme, and suggest the presence of independent domains for the binding of each substrate in homoserine kinase.

Functional group characterization of homoserine kinase from Escherichia coli

Homoserine kinase (EC 2.7.1.39), a key enzyme in the aspartate pathway of amino acid biosynthesis in Escherichia coli, catalyzes the phosphorylation of L-homoserine to form L-homoserine phosphate. The ThrB gene coding for this enzyme has been cloned, and the enzyme has been overexpressed and purified to homogeneity with a simplified purification scheme. An examination of the pH dependence of the V/K profile for L-homoserine shows that the enzyme loses activity upon protonation of a single functional group and upon de-protonation of a second functional group, with both groups appearing to be of the cationic acid type. Incubation of the enzyme with diethylpyrocarbonate leads to the complete loss of enzyme activity. Spectral and chemical characterization of the derivatized enzyme has shown that this activity loss is caused by the modification of a histidine residue. Treatment of the enzyme with pyridoxal-5'-phosphate also results in enzyme inactivation. The spectra evidence for the formation of a Schiff base, and the complete protection afforded by substrates and inhibitors, indicate that homoserine kinase also contains a lysine that is essential for catalytic activity.

[Clinical observation on perinatal Chlamydia trachomata infection]

OBJECTIVE

To screen antigen of genital chlamydia trachomata (CT) in pregnant women and to study its clinical characteristics, treatment and transmission to the newborns.

METHOD

Monoclone antibody immuno-fluorescence was employed in assaying.

RESULTS

Positive incidence of CT infection during pregnancy was 86 cases (26.88%), of whom 47/64 cases (73.44%) treated with traditional Chinese herbs for 2 weeks became negative. The other 22 were not treated because either they were too near to term (21 cases) or had local allergic reaction (1 case). Incidence of positive CT in newborns from untreated mothers was 81.82%, treated and became negative was 23.40%, treated but still positive was 88.24%.

CONCLUSION

Antenatal treatment is of importance in preventing intrapartum transmission of CT from mother to child. The data indicated that treatment with traditional Chinese herbs was effective.