[Expressions of survivin and nm23 and the relationship among the expressions and the axillary lymph node metastasis in breast cancer].

OBJECTIVE: To investigate the expressions of Survivin protein and nm23 protein and the relationship among the expressions and axillary lymph node metastasis in breast cancer. METHODS: The expression of Survivin and nm23 in 80 cases of breast cancer tissues were detected by immunohistochemistry SP method, and their correlation with axillary lymph node metastasis and 5-year disease free survival (DFS) were analysed. RESULTS: Survivin protein positive expression rate was 68.75% (55/80) in breast cancer tissues, which had positive correlation with the axillary lymph nodes metastasis but negative correlation with 5 years FS (P < 0.05); nm23 protein expression had negative correlation with the axillary lymph nodes metastasis but positive to 5 years FS (P < 0.05). Survivin and nm23 proteins expression had no obvious correlation with the breast cancer pathology type, patient age and clinical stage (P > 0.05). CONCLUSION: The anti-apoptosis effect of Survivin protein and the anti-metastasis effect of nm23 protein may be important in the occurrence and advancement of breast cancer, suggesting that it may be a new indicator of prognostic and judgement in breast cancer.

[Immunological screening of Toxoplasma tachyzoite cDNA expression libraries with serum from infected rats].

OBJECTIVE: To screen and identify the potential candidates for the development of toxoplasmosis vaccine. METHODS: Rats were infected with Toxoplasma gondii (T. gondii) RH strain and their sera were used as a probe to screen T. gondii tachyzoite cDNA expression libraries. The positive clones were analyzed by PCR amplification and DNA sequencing. RESULTS: Thirteen positive clones were obtained from about 4 x 10(5) phage plagues after three rounds of screening. The size of the inserts ranged from 0.45 kb to 2.4 kb. A BLAST search of all available sequence databases using the partial sequences from four positive clones (L1, L2, L4, L5) showed that the sequence of L2 clone was identical with T. gondii P24 major antigen gene (TgP24). Clone L4 had a high homology with Saccharum officinarum pyruvate orthophosphate dikinase. There is no significant hit of any sequences to clone L1, suggesting that L1 could be a novel gene(GenBank accession number AY180109), named T.g-R1, which encodes a non-transmembrane protein with 134 amino acid open reading frame. PROSCAN analysis of the T.g-R1 amino acid sequence showed that this gene product contains two protein kinase C phosphorylation site, two casein kinase II phosphorylation site, one N-myristoylation site and one microbodies C-terminal targeting signal. Clone L5 was a small partial fragment. CONCLUSION: The identification of positive clones provides a possible way for the development of toxoplasmosis vaccine.

[Analysis on morbidity and chemotherapy effects of Schistosoma japonicum infection in fishermen on Dongting Lake].

OBJECTIVE: To clarify and evaluate the morbidity of schistosome infection and the effectiveness of chemotherapy among fishermen on East Dongting Lake. METHODS: Information on water-contact, history of infection and of praziquantel (PZQ) treatment among fishermen was collected. Kato-Katz method and miracidium hatching test were applied to detect the pathogens in stool specimen. Serum antibodies against soluble egg antigen (SEA) were detected with ELISA and IHA. B-ultrasonic examination was used to determine the pathological changes of liver and spleen. Chemotherapy [PZQ 40 mg/(kg x d)] was given to the fishermen followed by a re-examination after a transmission season. RESULTS: The first investigation (six months before chemotherapy) showed that among 268 people inquired, 90.7% were frequently or intermittently contacting water, 24.0% were treated with PZQ each year, 39.4% had never been treated in the recent five years. Stool positive rate was 68.1% (111/163) and the geometric mean eggs per gram feces (EPG) were 48.77. Males had a higher infection rate (76.0%) and intensity (62.97 EPG) compared with that of females (58.7% infection rate and 30.42 EPG). The highest positive rate (83.3%) was in the age group of 11 to 20 years old. The prevalence of those who frequently or intermittently contacted water and were never treated before was 76.3% (106/139) and 79.7% (51/64), respectively. Serological positive rate was 88.0% (IHA) or 78.7% (ELISA). B-ultrasound revealed 77.4% (82/106) of the fishermen showing pathological changes in liver and/or spleen due to schistosomiasis. 37.7% of the patients showed II-III stage liver fibrosis (male: 53.0%, female: 15%), 58.5% hepatomegaly and 19.8% splenomegaly. The second investigation (six months after chemotherapy with PZQ) showed a stool positive rate of 35.4% and an average EPG 36.13 in the treatment group which were considerably lower than 56.5% infection rate and 68.47 EPG in the group without treatment. In 39 patients treated, the reversion rate from egg positive to negative was 48.7%, pathological change in liver and spleen declined by 40.6%. CONCLUSION: The prevalence and morbidity of schistosomiasis in fishermen on Dongting Lake were high due to frequent exposure to the affected water, and chemotherapy can effectively reduce the prevalence, the intensity of infection and morbidity of the fishermen.

[Improvement in the dot immunogold filtration assay].

OBJECTIVE: To improve the filtrating unit of the dot immunogold filtration assay (DIGFA) to reduce its cost and make it suitable for fieldwork. METHODS: A thick round filtrating paper disc was made to replace the plastic filtrating box, and their results were compared. RESULTS: The size of the self-made filtrating paper disc was smaller and the cost was lower. The efficacy of antibody examination by our paper disc was the same as that of the usual plastic filtrating box. CONCLUSION: In some aspects, the round filtrating disc is better than the plastic filtrating box.

[Construction and sequencing of recombinant plasmid pcDNA3/GRA1 from Toxoplasma gondii].

OBJECTIVE: To construct a mammalian expression plasmid pcDNA3/GRA1 to express dense granules antigen-1 (GRA1) of Toxoplasma gondii, and to lay a foundation for further studying the protective immunity of pcDNA3/GRA1 as a DNA vaccine. METHODS: The GRA1 opening reading frame (ORF) was amplified with two specific primers. The ORF and plasmid pcDNA3 were digested with EcoR I and Xho I respectively and the ORF was ligated into the pcDNA3 at polylinker. The recombinant vector pcDNA3/GRA1 was characterized by PCR, restriction enzyme digestion, and sequencing analysis. RESULTS: The expected ORF, 573 bp long, was amplified by PCR, and inserted into plasmid pcDNA3. PCR, restriction enzyme digestion and sequencing analysis showed that pcDNA3/GRA1 contained GRA1 ORF with the right orientation. CONCLUSION: The mammalian expression vector pcDNA3/GRA1 is successfully constructed.