Antitumor activity of recombinant antimicrobial peptide penaeidin-2 against kidney cancer cells / 华中科技大学学报（医学）（英德文版）

Penaeidin-2 (Pen-2) is an important antimicrobial peptide derived from the Pacific white shrimp, Penaeus vannamei, and possesses both antibacterial and antifungal activities. Recent studies suggest that recombinant penaeidins show similar activities to the native Pen-2 protein. Previous researches have shown that some antimicrobial peptides (AMPs) exhibit cytotoxic activity against cancer cells. To date, there have been no studies on the antitumor effects of Pen-2. This study evaluated the potential of recombinant pen-2 (rPen-2) in the selective killing of kidney cancer cell lines ACHN and A498, and its action mechanism. MTT assays found the maximal growth inhibition of HK-2, ACHN and A498 cells treated with 100 μg/mL rPen-2 at 48 h was 13.2%, 62.4%, and 70.4%, respectively. DNA-specific fluorescent dye staining showed a high percentage of apoptosis on cancer cells. Flow cytometry revealed that the apoptosis rate of HK-2, ACHN and A498 cells was 15.2%, 55.2%, and 61.5% at 48 h respectively, suggesting that rPen-2 induced higher apoptosis rate in cancer cells than in HK-2 cells. Laser confocal scanning microscopy demonstrated that the plasma membrane was the key site where rPen-2 interacted with and destroyed tumor cells. Scanning electron microscopy showed the morphologic changes of the cell membranes of kidney cancer cells treated with rPen-2. These results suggest that rPen-2 is a novel potential therapeutic agent that may be useful in treating kidney cancers.

Antitumor activity of recombinant antimicrobial peptide penaeidin-2 against kidney cancer cells / 华中科技大学学报（医学）（英德文版）

Penaeidin-2 (Pen-2) is an important antimicrobial peptide derived from the Pacific white shrimp, Penaeus vannamei, and possesses both antibacterial and antifungal activities. Recent studies suggest that recombinant penaeidins show similar activities to the native Pen-2 protein. Previous researches have shown that some antimicrobial peptides (AMPs) exhibit cytotoxic activity against cancer cells. To date, there have been no studies on the antitumor effects of Pen-2. This study evaluated the potential of recombinant pen-2 (rPen-2) in the selective killing of kidney cancer cell lines ACHN and A498, and its action mechanism. MTT assays found the maximal growth inhibition of HK-2, ACHN and A498 cells treated with 100 μg/mL rPen-2 at 48 h was 13.2%, 62.4%, and 70.4%, respectively. DNA-specific fluorescent dye staining showed a high percentage of apoptosis on cancer cells. Flow cytometry revealed that the apoptosis rate of HK-2, ACHN and A498 cells was 15.2%, 55.2%, and 61.5% at 48 h respectively, suggesting that rPen-2 induced higher apoptosis rate in cancer cells than in HK-2 cells. Laser confocal scanning microscopy demonstrated that the plasma membrane was the key site where rPen-2 interacted with and destroyed tumor cells. Scanning electron microscopy showed the morphologic changes of the cell membranes of kidney cancer cells treated with rPen-2. These results suggest that rPen-2 is a novel potential therapeutic agent that may be useful in treating kidney cancers.

Morphologic features of sudden cardiac death in Yunnan province, with emphasis on myocarditis / 中华病理学杂志

<p><b>OBJECTIVES</b>To study the pathologic feature of sudden cardiac death in Yunnan province and to investigate the role of myocarditis.</p><p><b>METHODS</b>During the period from 1991 to 2006, there were 29 cases of sudden cardiac death with autopsy performed. Fourteen of these cases were diagnosed to have myocarditis based on Dallas criteria and World Heart Federation's consensus. The clinical and pathologic findings were reviewed. The cardiac conduction system was examined in details by serial sectioning in 3 cases.</p><p><b>RESULTS</b>Fourteen cases suffered with myocarditis, which accounted for 48% of all cases of sudden cardiac death studied. The age of the deceased ranged from 8 to 68 years (mean = 30 years), with male-to-female ratio equaled to 9:5. Lymphocytic myocarditis and neutrophil myocarditis were the two major types, affecting 11 and 3 cases, respectively. The inflammatory infiltrates were often patchy rather than diffuse. The inflammatory foci were detected only in 8% to 42% (average = 20%) of the paraffin sections of the heart tissue. These lesions were usually located in the lateral wall of left ventricle and occasionally in interventricular septum and right ventricular wall. Myocardial injury was mild in most cases while patchy myocytolysis or coagulation necrosis was observed only in a few cases. Most of the lesions were relatively new and histologic evidence of myocardial repairing sometimes coexisted. Pericarditis and subacute endocarditis were also identified in 4 and 1 cases, respectively. Atrioventricular node was involved by myocarditis in 1 of the 3 cases examined for cardiac conduction system. Two cases showed gross evidence of cardiac dilatation (either left ventricle or biventricular). Respiratory tract and pulmonary infection was present in 5 cases.</p><p><b>CONCLUSIONS</b>Myocarditis represents one of the major pathologic changes of sudden cardiac death occurring in Yunnan province. The inflammation is usually focal. Further studies are required for delineation of possible etiologies which may include virus, bacteria or exogenous toxin.</p>

Development of Lateral-flow Immunoassay for WSSV with Polyclonal Antibodies Raised against Recombinant VP (19+28) Fusion Protein / 中国病毒学

We have developed a sensitive and rapid lateral-flow immunoassay (LFIA) for WSSV,using colloidal gold as an indicator.The fusion protein,VP (19+28),was expressed in E.coli,purified and used to prepare polyclonal antibodies.The purified anti-VP (19+28) IgG were conjugated with colloidal gold.Unconjugated anti-VP (19+28) IgG and goat anti-rabbit IgG were immobilized on nitrocellulose membranes.After assembly,three groups (5 individual animals in each group) of shrimp samples were tested which included healthy,moribund and dead shrimps.For each group,three different tissues (body juices,gills and hepatopancreas) were tested at the same time.In parallel,all the samples were also analyzed using PCR for comparison.Out of 45 samples tested,30 were detected as positive while 15 were classified as negative.The results of LFIA correlate with those obtained by the PCR analysis,indicating that these two detection methods have the same efficacy in the limited number of samples tested in this preliminary study.

Comparison of Producing Dendrolimus punctatus Cytoplasmic Polyhedrosis Virus in Substitutive Host Insect / 中国病毒学

Argyrogramma agnata has been selected as a substitutive host insect for producing Dendrolimus punctatus Cytoplasmic Polyhedrosis Virus (DpCPV). In our experiment, it is very susceptible to DpCPV. The DpCPV produced in A. agnata is designated Aa-DpCPV. The cytoplasmic polyhedra body (CPB), the virion size and the shape of Aa-DpCPV are same as that of its original DpCPV (DpCPV-W1984). The RNA bands of Aa-DpCPV and DpCPV-W1984 all have 10 RNA segments respectively in 3% PAGE, which molecular weights ranged in size from 2.98×106 to 0.66×106 Dalton. Aa-DpCPV has the same strong toxicity as that of DpCPV-W1984 (from D. punctatus) to D. punctatus (Walker) larva. So it can be applied to the pine caterpillar control. The DpCPV yield in A.agnata is 2.5×108CPB/larva.