Banana bunchy top virus (BBTV) nuclear shuttle protein interacts and re-distributes BBTV coat protein in Nicotiana benthamiana.

Banana bunchy top virus (BBTV) is a circular single-stranded DNA virus with multi-components. The knowledge about interaction between viral proteins and pathogenesis mechanism of BBTV remains unclear. In this study, the coat protein gene (CP, ORF 516 bp) and nuclear shuttle protein gene (NSP, ORF 465 bp) from BBTV B2 isolate of the Southeast-Asia group were cloned. The intracellular localization analysis showed the CP locates in the cell nucleus of tobacco cells, while the NSP distributes in the cell nucleus and cytoplasm. Co-localization analysis indicated the NSP itself does not change distribution, but CP re-distributes to the cell nucleus and cytoplasm, suggesting that NSP interacts with CP and re-locates the CP in the cell. The interaction between CP and NSP was further verified by co-immunoprecipitation (Co-IP) in tobacco protoplasts. The study will help us to understand the interaction between viral proteins and pathogenesis mechanism of BBTV in host plants.

Comparison of flavonoids, phenolic acids, and antioxidant activity of explosion-puffed and sun-dried jujubes (Ziziphus jujuba Mill.).

The goal of the present study was to investigate the effect of explosion puffing and sun-drying on individual phenolic acids in four forms (free, esters, glycosides, and insoluble-bound), flavonoids, total phenolic content (TPC), and their antioxidant activity on jujube samples. Phenolic compounds were identified and quantified using high-performance liquid chromatography. Antioxidant capacity of jujube samples was evaluated by 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity and total reducing power. The results showed that all samples significantly differed in their phenolic contents, phenolic acid and flavonoid composition, and antioxidant activities. The explosion-puffed jujubes had the highest total gallic, p-hydroxybenzoic, vanillic, p-coumaric, ferulic acids, and rutin contents. Also, explosion-puffed jujubes contained a higher level of total phenolics and antioxidant activity than their counterparts. Among phenolic acid fractions in four forms, each form of phenolic acids in explosion-puffed jujubes had the most abundant content, followed by fresh and sun-dried jujubes. The glycosided and insoluble-bound phenolic acid fractions for each sample represented the highest TPC and the strongest antioxidant activity. The results indicated explosion puffing was a good choice for jujube processing.

[Analysis of the common morphological characteristics of cancerous cells using atomic force microscope].

OBJECTIVE: To observe the surface ultrastructure of different tumor cells in vivo using atomic force microscope (AFM) and analyze their common characteristics. METHODS: We selected 60 specimens of each of normal liver cells, liver cancer, cervical squamous cells, cervical cancer cells, ductal epithelial cells and breast cancer cells for scanning using AFM. The cell surface scan images were analyzed using image analysis software to identify their common morphological features. RESULTS: From normal cervical squamous epithelial cells, intermediate cells, and basal cells to HPV-infected cells, CIN2-3 cells and cervical cancer cells, the membrane surface roughness became gradually increased (P<0.05). Similarly, the surface roughness increased significantly in the order of normal liver cells, hepatitis B cirrhosis liver cells, and hepatocellular carcinoma cells (P<0.05). The average surface roughness also tended to increase from normal mammary gland cells to mammary gland hyperplasia cells and breast cancer cells (P<0.05). CONCLUSION: Normal cells and tumor cells show different cell membrane morphologies, and such morphological features provide a reliable basis for clinical pathological diagnosis and differential diagnosis of malignancies.

Relationship between lymph node sinuses with blood and lymphatic metastasis of gastric cancer.

AIM: To elucidate the relationship between lymph node sinuses with blood and lymphatic metastasis of gastric cancer. METHODS: Routine autopsy was carried out in the randomly selected 102 patients (among them 100 patients died of various diseases, and 2 patients died of non-diseased reasons), their superficial lymph nodes locating in bilateral necks (include supraclavicle), axilla, inguina, thorax, and abdomen were sampled. Haematoxylin-Eosin staining was performed on 10 % formalin-fixed and paraffin-embedded lymph node tissue sections (5 um). The histological patterns of the lymph sinuses containing blood were observed under light microscope. The expression of CD31, a marker for endothelial cell, was detected both in blood and non-blood containing lymph node sinuses with the method of immunohistochemistry. RESULTS: Among the 1 322 lymph nodes sampled from the autopsies of 100 diseased cases, lymph node sinuses containing blood were found in 809 lymph nodes sampled from 91 cases, but couldn't be seen in the lymph nodes sampled from the non-diseased cases. According to histology, we divided the blood containing lymph node sinuses into five categories: vascular-opening sinus, blood-deficient sinus, erythrophago-sinus, blood-abundant sinus, vascular-formative sinus. Immunohistochemical findings showed that the expression of CD31 was strongly positive in vascular-formative sinuses and some vascular-opening sinuses while it was faint in blood-deficient sinuses, erythrophago-sinuses and some vascular-opening sinuses. It was almost negative in blood-abundant sinus and non-blood containing sinus. CONCLUSION: In the state of disease, the phenomenon of blood present in the lymph sinus is not uncommon. Blood could possibly enter into the lymph sinuses through the lymphaticovenous communications between the veins and the sinuses in the node. Lymph circulation and the blood circulation could communicate with each other in the lymph node sinuses. The skipping and distal lymphatic metastasis of gastric cancer may have some connection with the blood containing lymph node sinuses.