Observing astrocyte polarization in brains from mouse chronically infected with Toxoplasma gondii.

Toxoplasma gondii (T. gondii) is a protozoan parasite that infects approximately one-third of the global human population, often leading to chronic infection. While acute T. gondii infection can cause neural damage in the central nervous system and result in toxoplasmic encephalitis, the consequences of T. gondii chronic infection (TCI) are generally asymptomatic. However, emerging evidence suggests that TCI may be linked to behavioral changes or mental disorders in hosts. Astrocyte polarization, particularly the A1 subtype associated with neuronal apoptosis, has been identified in various neurodegenerative diseases. Nevertheless, the role of astrocyte polarization in TCI still needs to be better understood. This study aimed to establish a mouse model of chronic TCI and examine the transcription and expression levels of glial fibrillary acidic protein (GFAP), C3, C1q, IL-1α, and TNF-α in the brain tissues of the mice. Quantitative real-time PCR (qRT-PCR), enzyme-linked immunosorbent assay, and Western blotting were employed to assess these levels. Additionally, the expression level of the A1 astrocyte-specific marker C3 was evaluated using indirect fluorescent assay (IFA). In mice with TCI, the transcriptional and expression levels of the inflammatory factors C1q, IL-1α, and TNF-α followed an up-down-up pattern, although they remained elevated compared to the control group. These findings suggest a potential association between astrocyte polarization towards the A1 subtype and synchronized changes in these three inflammatory mediators. Furthermore, immunofluorescence assay (IFA) revealed a significant increase in the A1 astrocytes (GFAP+C3+) proportion in TCI mice. This study provides evidence that TCI can induce astrocyte polarization, a biological process that may be influenced by changes in the levels of three inflammatory factors: C1q, IL-1α, and TNF-α. Additionally, the release of neurotoxic substances by A1 astrocytes may be associated with the development of TCI.

Bulleyaconitine A Effectively Relieves Allergic Lung Inflammation in a Murine Asthmatic Model.

BACKGROUND Bulleyaconitine A (BLA) has been widely used as analgesic against chronic inflammatory pain in China. However, its potential therapeutic role in asthma remains unclear. The purpose of this study was to investigate the effect of BLA on airway inflammation in mice with allergic asthma. MATERIAL AND METHODS Specific-pathogen-free (SPF) female Balb/c mice were randomly divided into the following 6 groups: (1) Control group (NC), (2) Asthma group (AS), (3) BLA-L group, (4) BLA-M group, (5) BLA-H group, and (6) Dexamethasone group. An asthma mouse model was established by administration of ovalbumin (OVA) and mice were sacrificed within 24 h after the last challenge. Enzyme-linked immunosorbent assay (ELISA) method was used to determine the relative expression levels of IgE and IgG in mouse serum. In addition, bronchoalveolar lavage fluid (BALF) was collected and IL-4, TNF-α, and MCP-1 levels were determined by ELISA. Furthermore, eosinophils, lymphocytes, and macrophages in BALF were classified and analyzed, and inflammatory cell infiltration in the airways of mice was determined by hematoxylin-eosin (HE) staining. The expression of NF-κB1 and PKC-δ in mouse lung tissue was determined by Western blot analysis. RESULTS The levels of serum IgE and IgG in BLA- or Dex- treated mice were significantly reduced compared to those in the asthma (AS) group (P<0.01), whereas the levels of cytokines IL-4, TNF-α, and MCP-1 were significantly decreased (P<0.01). HE-staining showed that BLA significantly reduced inflammatory cell infiltration and mucus secretion in lung tissue. Moreover, BLA inhibited the expression of NF-κB1 and PKC-d via the NF-κB signaling pathway in the lung. CONCLUSIONS Our data show that BLA activates PKC-δ/NF-κB to reduce airway inflammation in allergic asthma mice.

A Polysaccharide from Amusium Pleuronectes Combined with Praziquantel Treatment Ameliorates Hepatic Fibrosis in Schistosoma Japonicum-Infected Mice.

BACKGROUND Polysaccharides from bivalves have multiple bioactivities in various aspects of biology. However, the role of a polysaccharide derived from Amusium pleuronectes on potential hepatoprotective effects remains unclear. MATERIAL AND METHODS A water-soluble polysaccharide was isolated from Amusium pleuronectes (APS-1) using ultrasound-assisted hot-water extraction. The molecular weight of APS-1 was approximately 11.7 kDa and was determined by calibration with dextran. APS-1 was analyzed by high-performance liquid chromatography (HPLC), and mainly consisted of a uniform glucose polymer. The protective effect of APS-1 on Schistosoma japonicum-induced liver fibrosis was investigated in a mouse model. RESULTS Treatment with APS-1 increased serum levels of interleukin (IL)-12 and interferon (IFN)-γ, increased superoxide dismutase (SOD) activity, and decreased levels of IL-13 and IL-5, and hyaluronidase activity. Moreover, immunohistochemical analysis revealed that the collagen content of hepatic tissue of APS-1-treated mice, including that of collagen I, II, and IV, was dramatically decreased. Furthermore, our data showed that combined treatment of APS-1 with praziquantel had more pronounced effects than treatment with either APS-1 or praziquantel alone. CONCLUSIONS Our findings suggest that the treatment using APS-1 in combination with praziquantel attenuated S. japonicum egg-induced hepatic fibrosis, and possessed potent hepatoprotective activity.

[Adult of Drosophila melanogaster parasitized in human nasal cavity: a case report].

We reported a case of adult Drosophila melanogaster parasitized in nasal cavity of a 81-year-old woman who was living in Xuancheng City, Anhui Province now. She was admitted for treatment of cerebral infarction and water accumulation in the lungs in 2014 June. The patient was also suffering from secretory otitis media, a history of hypertension and heart stents were placed in 2007. A foreign body was found in the left nasal cavity during the preoperative examination process, and then the part of the inflammatory tissue was removed through the nasal endoscopy, and sent to our department for identification. There are three adults of Drosophila in paraffin-embedded biopsy specimens. The parasites length is approximately 3mm, with huge red compound eyes. The end of the body is tip, with 5 ring lines in back, has no dark spots. The abdomen of the parasites have seven sections. Tarsus of foot I have no sex comb on base, and they are male adult of Drosophila melanogaster after identification. After a thorough reviewing of medical history, we knew the patient began to sneeze violently and frequently six years ago. But there was no clear or purulent nasal discharge flowing, therefore did not attract attention. After removing the parasites the sneezing symptoms were relieved, and had no abnormal symptoms in the follow-up 6 months.

[Experimental study on determination of viability of Schistosoma japonicum cercariae by staining].

OBJECTIVE: To determine the viability of Schistosoma japonicum cercariae by staining. METHODS: Schistosoma japonicum cercariae were stained by 0.4% trypan blue, 0.5% methylene blue-eosin-borax (M.E.B), 0.5% eosin, 0.5% methylene blue and 0.05% neutral red, respectively, for 5 min, then they were observed under a stereoscopic microscope. RESULTS: The dead cercariae were stained in the trypan blue, M.E.B, eosin and neutral red, but unstained in the methylene blue. The vital cercariae were unstained in all the five kinds of dyes. CONCLUSION: The staining methods by using 0.4% trypan blue, 0.5%M.E.B, 0.5% eosin and 0.05% neutral red can be used to determine the viability of S. japonicum cercariae.

Preliminary report on the intestinal parasites and their diversity in captive Chinese alligators.

OBJECTIVE: Although intestinal parasites are commonly detected in either wild or farmed crocodiles in other parts of the world, yet few reports have ever been on the captive bred Chinese alligators (Alligator sinensis) since they are only distributed in the southern areas of the Yangtze River. The current work was undertaken to investigate the intestinal parasites and their diversity in the Chinese crocodilian species. METHODS: In May and October of 2013, we randomly collected a total of 328 fecal samples of the captive Chinese alligators in a breeding centre in south Anhui province. RESULTS: Three genera of protozoa (Entaoeba, Eimeria and Isospora), five genera of nematodes (Ascaris, Dujardinascaris, Capillaria, Toxocara and Strongylus), two genera of trematodes (Echinostoma and Clonorchis) and two families of trematodes (Schistosomatidae and Cryptogonimidae) were identified, in which Dujardinascaris was the most prevalent and led to the highest infection rate (14.33%), and Entaoeba ranked the second (13.11%). The number of species, richness index, diversity index and evenness index were higher in July and August, and those indexes were relatively most in juvenile and subadult alligators. CONCLUSIONS: Our findings suggest that the intestinal parasites infection was prevalent in captive Chinese alligators, and this condition requires our attention, whatever it is for controlling or preventing the intestinal parasitic disease from spreading to humans or conservation of this endangered species.

Objetivo: Aunque los parásitos intestinales son comúnmente detectados en los cocodrilos salvajes o en criados en cautividad en otras partes del mundo, existen muy pocos informes el caso concreto del caimán chino criado en cautividad (Alligator sinensis), ya que sólo están distribuidos en las zonas del sur del río Yangtze. El presente trabajo fue realizado para investigar los parásitos intestinales y su diversidad en las especies de cocodrilo chino. Métodos: En mayo y octubre de 2013, se recopilaron aleatoriamente un total de 328 muestras fecales de caimanes chinos en cautividad de un centro de cría en el sur de la provincia de Anhui. Resultados: Fueron identificados tres géneros de protozoos (Entaoeba, Eimeria e Isospora), cinco géneros de nematodos (Ascaris, Dujardin Ascaris, Capillaria, Toxocara y Strongylus), dos géneros de trematodos (Echinostoma y Clonorchis) y dos familias de trematodos (Schistosomatidae y Cryptogonimidae), de los cuales la mayor prevalencia correspondió a Dujardin Ascaris y producían la mayor tasa de infección (14,33%); entaoeba se situó en el segundo puesto (13,11%). El número de especies, índice de riqueza, índice de diversidad y de equitatividad fue superior en los meses de julio y agosto, y éstos, relativamente más para caimanes jóvenes y sub-adultos. Conclusiones: Nuestros resultados apuntan la prevalencia de la infección por parásitos intestinales en caimanes chinos en cautividad y ello exige nuestra atención, ya sea para controlar o prevenir la propagación de la enfermedad parasitaria intestinal a los seres humanos, o para la conservación de esta especie en peligro de extinción.

[Preliminary studies on effect of polysaccharides from Tegillarca granosa as an adjuvant on DNA vaccine against Schistosoma japonicum infection].

OBJECTIVE: To discuss the effect of polysaccharides from Tegillarca granosa as an adjuvant on pcDNA3.1-Sj26GST vaccine against Schistosoma japonicum infection. METHODS: Sixty SPF BALB/c mice were divided into four groups randomly (15 mice each group), including a control group, a polysaccharides group, a vaccine group, and a vaccine plus polysaccharides group. In the 0, 2th and 4th week of the experiment, the mice in the above four groups were immunized for 3 times with 100 µl PBS, 100 µg polysaccharides from Tegillarca granosa, 100 µg Sj26GST vaccine, and 100 µg Sj26GST vaccine plus equivalent polysaccharides, respectively. Two weeks after the last immunization, all the mice were infected with 40 ± 1 Schistosoma japonicum cercariae through the skin of the abdomen. After the infection for 6 weeks, all the mice were sacrificed, and their serums, livers and the adult worm of Schistosoma japonicum in them were collected, the specific sera IgG antibodies were detected by ELISA, and the worm reduction rates and egg reduction rates in the liver were calculated. RESULTS: Six weeks after the infection, the IgG antibody levels of the mice in the vaccine group and the vaccine plus polysaccharides group were 18.26 ± 0.42 mg/ml and 20.21 ± 0.89 mg/ml respectively, the difference between them were statistically significant, and both of the IgG levels of the above groups were significantly higher than those in the control (both P < 0.05). The worm reduction rate and egg reduction rate in the vaccine group were 28.60% and 35.84%, respectively, and the rates in the vaccine plus polysaccharides group were 38.04% and 49.74%, respectively, the differences between the worm reduction rates and egg reduction rates were both statistically significant (both P < 0.05). Meanwhile, the two rates in the two above groups were all significantly higher than those in the control group (all P < 0.01). CONCLUSION: Polysaccharides from Tegillarca granosa using as an adjuvant can increase the protection effect of pcDNA3.1-Sj26GST vaccine against Schistosoma japonicum infection.

[Preliminary studies on protective immunity induced by recombinant protein of Schistosoma japonicum P14 gene and its mechanism against schistosome infection in mice].

OBJECTIVE: To explore the immune protective effect of the basic calponin-like protein (SjP14) in mice response to the infection of Schistosoma japonicum. METHODS: The recombinant plasmid pET28a(+)-SjP14 was built, and transferred into E. coli BL21 cell line. After induced, by isopropyl-beta-D-thiogalactoside (IPTG), the target protein was purified, and then analyzed by SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting, respectively. Thirty female BALB/c mice (six-week age) were randomly divided into three groups (n = 10 for each), including A group (rSjP14 experimental), B group (adjuvant control), and C group (saline control). The mice in the A group were subcutaneously injected with 100 microg rSjP14 vaccine for three times at 2-week interval. After the final immunization, the mice were infected by cercariae of S. japonicum. The B or C groups experienced subcutaneous injections of adjuvant or saline, respectively, except for cercaria infection. The levels of sera IgG, IL-4 and IFN-gamma were detected by ELISA before immunizing, 6 weeks after immunizing, and 6 weeks after the infection, respectively. The reduction rates of worms or eggs were also calculated at the 6th week after the infection. RESULTS: The SjP14 protein was about 38 kDa and was recognized successfully by polyclonal antibody of SjP14. The level of serum IgG in the A group at the 6th week after the infection of cercariae was significant increased [ (25.52 +/- 1.91) microg/ml] compared with that in the B [ (18.65 +/- 3.16) microg/ml] and C [(22.44 +/- 2.83) mcirog/ml] groups (P < 0.05); the level of serum IFN-gamma [(171.30 +/- 70.12) ng/L] was also increased, compared with that in the B [(136.89 +/- 37.62) ng/L] and C [(153.64 +/- 43.44) ng/L] groups (P < 0.05). However, the level of serum IL-4 [(112.05 +/- 15.02) ng/L] in A group was significant decreased at the 6th week after the infection, compared with that in the C group [(102.82 +/- 27.46) ng/L] (P < 0.05). The reduction rates of worms and eggs in the A group were 29.2% and 41.3%, respectively, after the infection, which had statistically significant differences compared with those of the C group (P < 0.05). CONCLUSION: SjP14 has a protective immunity against S. japonicum infection in mice.

[Killing effect of exogenous NO on cercariae of Schistosoma japonicum in vitro].

OBJECTIVE: To explore the killing effects of exogenous NO on the cercariae of Schistosoma japonicum in vitro and the blocking effects of NO inhibitors. METHODS: The cercariae of S. japonicum were collected from naturally infected snails, and then formulated into a 1000 cercariae/ml suspension with RPMI 1640 medium. The relationship between the killing effects and doses of exogenous NO on cercariae were investigated through the suspension with different concentrations of NO generating agents (SNP) and negative control (without SNP). On the other hand, the blocking effects were also investigated through the suspensions being added 2.00 mmol/L SNP and four different NO inhibitors, Hb, FeSO4, L-cyst, L-arg and their combination. Additionally, the appropriate positive(2.00 mmol/L SNP) and negative controls (without NO generating agent) were used. RESULTS: The mortality rates of cercariae were (8.3 +/- 1.1)%, (6.26 +/- 2.3)%, and (9.3 +/- 1.0)% in the SNP 0.06, 0.1 and 0.2 mmol/L groups, respectively, and there were no statistically significant differences between the blank control group and the above-mentioned three groups, respectively (P > 0.05). The mortality rates of cercariae were(23.5 +/- 3.9)%, (46.0 +/- 1.1)%, and (59.4 +/- 0.5)% in the SNP 0.50, 1.00 and 2 mmol/L groups, respectively, and there were statistically significant differences between the blank control group and the above-mentioned groups, respectively (P < 0.05). The mortality rates of cercariae were (30.1 +/- 1.2)%, (45.1 +/- 1.4)%, (31.1 +/- 1.3)%, (34.2 +/- 3.1)%, (47.8 +/- 2.0)%, (49.1 +/- 0.6)%, and (44.2 +/- 0.1)% in the 2.00 mmol/L SNP suspensions which were added of Hb, FeSO4, L-cyst, L-arg, FeSO4+L-cyst, FeSO4+L-arg, FeSO4+L-arg+L-cyst, respectively. Compared with the 2.00 mmol/L SNP suspension, the mortality rates of the above-mentioned groups declined, and there were statistically significant differences (P < 0.05). CONCLUSION: There are killing effects of exogenous NO on the cercariae of S. japonicum in vitro, and four different NO inhibitors, Hb, FeSO4, L-cyst, L-arg and their combinations have some different degrees of blocking effects.

[Reform and practice on the experiment teaching of medical parasitology].

A new model of education is investigated to meet the new idea of experiment teaching in university. Therefore the establishment of experiment teaching model of medical parasitology needs to be correspondently reformed. A variety of new management measures are taken to raise the efficiency of experiment teaching in training the students in the College.