There has been no study aimed at directly determiningof the periods of Sertoli cell proliferation in birds evendomestic fowl. The aims of this study were to observe thecessation of post-hatching mitotic proliferation of Sertolicells in domestic fowl, and to determine the volumedensity of Sertoli and germ cells during this period. Atotal of 50 Leghorn chicks were used in this study. Thetestes sections of the animals were immunostained withBrdU to observe the proliferation of cells from one to 10weeks of age. The volume density of the Sertoli and germcells were determined using the standard point countingmethod. The volume density of the germ cell nuclei wasinitially less than that of the Sertoli cells but the volumedensity converged by week 6, and remained relativelyconstant until the commencement of meiosis. Clearlabeling of Sertoli and germ cells was observed from week1 to week 7. The only those cells still labeled after 8 weekswere germ cells, indicating that Sertoli cell proliferationhad ceased. Therefore, it is recommended that anyresearch into the testes of domestic fowl should considerthe cessation of Sertoli cell proliferation by approximately8 weeks.
Animals ; Bromodeoxyuridine/metabolism ; Cell Differentiation/physiology ; Cell Growth Processes/physiology ; Chickens/*physiology ; Histocytochemistry/veterinary ; Male ; Mitosis/physiology ; Sertoli Cells/*cytology/metabolism ; Spermatocytes/cytology ; Testis/*cytology/metabolism

OBJECTIVETo investigate whether vascular endothelial growth factor (VEGF) gene plasmid carried by polytetrafluoroethylene (PTFE) vascular graft materials could transfect endothelial cells (ECs) and promote their growth.

METHODSPTFE vascular graft materials carried with pCDI-hVEGF(121), pCDI or pEGFP were incubated in Tris-buffer solution and the values of optical density of 260 nm at different time were plotted, then the DNA controlled release curve was made. ECs derived from human umbilical vein were seeded on the pCDI-hVEGF(121)/pCDI/pEGFP-PTFE materials or tissue culture plates, ECs numbers were counted and VEGF protein concentrations at different time were measured by enzyme-linked immunoadsorbent assay method. Green fluorescent protein (GFP) expression in ECs on pEGFP-PTFE materials was examined with fluorescence microscopy.

RESULTSThe controlled release curve showed that the gene released from PTFE materials was rapid within 8 h, then slowed down and that the gene released continuously even after 72 h. At 24, 72 and 120 h, ECs number and proliferation rate of pCDI-hVEGF(121)-PTFE materials were higher than those of pCDI or pEGFP-PTFE materials (P<0.05). VEGF protein concentration of pCDI-hVEGF(121)-PTFE materials was higher than that of pCDI or pEGFP-PTFE materials at 6, 24, 72 and 120 h (P<0.01). GFP expression in ECs on the pEGFP-PTFE materials could be detected by fluorescence microscopy.

CONCLUSIONPTFE graft can be used as a carrier of VEGF gene plasmid, VEGF gene carried by PTFE can transfect ECs and promote ECs growth.

Blood Vessel Prosthesis ; Cell Adhesion ; physiology ; Cell Growth Processes ; physiology ; DNA ; chemistry ; genetics ; Endothelial Cells ; cytology ; physiology ; Humans ; Plasmids ; chemistry ; genetics ; Polytetrafluoroethylene ; Transfection ; methods ; Vascular Endothelial Growth Factor A ; genetics

BACKGROUNDSam68 plays an important role as a multiple functional RNA binding nuclear protein in cell cycle progress, RNA usage, signal transduction, and tyrosine phosphorylation by Src during mitosis. However, its precise impact on these essential cellular functions remains unclear. The purpose of this study is to further elucidate Sam68 functions in RNA metabolism, signal transduction regulation of cell growth and cell proliferation in DT40 cell line.

METHODSBy using gene targeting method, we isolated a mutation form of Sam68 in DT40 cells and described its effect on cell growth process and signal transduction. Southern, Northern, and Western blot, phosphorylation and flow-cytometric analyses were performed to investigate the Sam68 functions.

RESULTSA slower growth rate (2.1 hours growth elongation) and longer S phase (1.7 hours elongation) was observed in the Sam68 mutant cells. Serum depletion resulted in increased amounts of dead cells, and expansion of S phase in mutant cells. Upon B cell cross-linking, the maximal level of tyrosine phosphorylation on BLNK was observed to be significantly lower in mutant cells.

CONCLUSIONSThe proline rich domain of Sam68 is involved in cell growth control by modulating the function of mRNAs in S phase or earlier and the functions as an adaptor molecule in B cell signal transduction pathways.

Adaptor Proteins, Signal Transducing ; genetics ; metabolism ; physiology ; Animals ; B-Lymphocytes ; cytology ; immunology ; physiology ; Binding Sites ; genetics ; Blotting, Western ; Cell Cycle ; physiology ; Cell Death ; physiology ; Cell Growth Processes ; drug effects ; physiology ; Cell Line, Tumor ; Culture Media, Serum-Free ; pharmacology ; Mutation ; genetics ; Phosphorylation ; Proline ; genetics ; RNA-Binding Proteins ; genetics ; metabolism ; physiology ; Receptors, Antigen, B-Cell ; immunology ; physiology ; Signal Transduction ; drug effects ; physiology ; Tyrosine ; metabolism

A normal prion protein (PrPc) is converted to a proteaseresistant isoform by an apparent self-propagating activity in transmissible spongiform encephalopathy, a neurodegenerative disease. The cDNA encoding open reading frame (ORF) of the bovine prion protein gene (Prnp) was cloned from Korean cattle by PCR, and was transfected into Chinese hamster ovary (CHO-K1) cells using lipofectamine. The gene expression of the cloned cDNA was confirmed by RT-PCR and Western blotting with the monoclonal antibody, 6H4. Cellular changes in the transfected CHO-K1 cells were investigated using parameters such as MTT, lactate dehydrogenase (LDH), and superoxide dismutase (SOD) activities, as well as nitric oxide (NO) production, and an apoptosis assay. In the MTT and LDH assays, the bovine PrnP-transfectant showed a lower proliferation rate than the wild-type (p < 0.05). Production of NO, after LPS or ConA stimulation, was not detected in either transfectants or CHO-K1 cells. In SOD assay under ConA stimulation, the SOD activity of transfectants was 10 times higher than that of CHO-K1 cells at 6 h after treatment (p < 0.05). The genomic DNA of both the transfectants and control cells began to be fragmented at 6 h after treatment with cyclohexamide. Caspase-3 activity was reduced by transfection with the bovine Prnp (p < 0.05). Conclusively, the viability of transfectants expressing exogenous bovine Prnp was decreased while the capacities for cellular protection against antioxidative stress and apoptosis were increased.
Animals ; Apoptosis/physiology ; CHO Cells/cytology/enzymology/*physiology ; Caspase 3/metabolism ; Cattle ; Cell Growth Processes/physiology ; Cloning, Molecular ; Cricetinae ; Cricetulus ; Encephalopathy, Bovine Spongiform/genetics/*pathology ; Formazans ; Hydro-Lyases/metabolism ; Nitric Oxide/metabolism ; Prions/biosynthesis/genetics/*physiology ; Superoxide Dismutase/metabolism ; Tetrazolium Salts ; Transfection

OBJECTIVETo investigate the effects of Nocardia rubra cell wall skeleton (Nr-CWS) on the HeLa cell line, one of the cell lines of human cervical cancer, infected with HPV.

METHODSHPV-infected HeLa (HPV 18-positive cells) cultured in vitro were divided into two groups: the experiment group and control group. Nr-CWS was added to the experiment group and PBS to the control. The growth and proliferation of HeLa cells were detected with MTT and flow cytometry technology. Inhibitive effect of HeLa transplanted tumor was investigated in Scid mice.

RESULTSThe growth of HeLa cells in the experimental group was apparently decreased compared with that of the control. The results of flow cytometry demonstrated that more HeLa cells were transferred into quiescent phase in the experimental group than that in the control. While less in the proliferative phase, both of the volume and weight of HeLa transplanted tumor with drug-added group were less than those of control group.

CONCLUSIONThe Nocardia rubra cell wall skeleton is a potiental growth inhibitor and inducer of apoptosis of cervical cancer cells in vitro and may provide a new way in prevention or supplementary management of anti-human papilloma virus.

Animals ; Cell Growth Processes ; drug effects ; Cell Survival ; drug effects ; Cell Wall Skeleton ; pharmacology ; therapeutic use ; Female ; Flow Cytometry ; HeLa Cells ; Host-Pathogen Interactions ; Humans ; Mice ; Mice, SCID ; Nocardia ; metabolism ; Papillomaviridae ; physiology ; Uterine Cervical Neoplasms ; pathology ; prevention & control ; virology ; Xenograft Model Antitumor Assays

This study was carried out to investigate fifteen cases of acute lethal infection of calves (< or = 4 months of age) by the protozoan parasite Theileria (T.) annulata in the south of Portugal. Calves developed multifocal to coalescent nodular skin lesions, similar to multicentric malignant lymphoma. Infestation with ticks (genus Hyalomma) was intense. Theileria was seen in blood and lymph node smears, and T. annulata infection was confirmed by isolation of schizont-transformed cells and sequencing of hypervariable region 4 of the 18S rRNA gene. At necropsy, hemorrhagic nodules or nodules with a hemorrhagic halo were seen, particularly in the skin, subcutaneous tissue, skeletal and cardiac muscles, pharynx, trachea and intestinal serosa. Histologically, nodules were formed by large, round, lymphoblastoid neoplastic-like cells. Immunohistochemistry (IHC) identified these cells as mostly CD3 positive T lymphocytes and MAC387 positive macrophages. A marker for B lymphocytes (CD79alphacy) labeled very few cells. T. annulata infected cells in these nodules were also identified by IHC through the use of two monoclonal antibodies (1C7 and 1C12) which are diagnostic for the parasite. It was concluded that the pathological changes observed in the different organs and tissues were caused by proliferation of schizont-infected macrophages, which subsequently stimulate a severe uncontrolled proliferation of uninfected T lymphocytes.
Animals ; Base Sequence ; Cattle ; Cattle Diseases/epidemiology/*parasitology/pathology ; Cell Growth Processes/physiology ; DNA, Protozoan/chemistry/genetics ; Disease Outbreaks/*veterinary ; Female ; Immunohistochemistry/veterinary ; Lymphocytes/parasitology/*pathology ; Male ; Molecular Sequence Data ; Polymerase Chain Reaction/veterinary ; Portugal/epidemiology ; RNA, Ribosomal, 18S/chemistry/genetics ; Sequence Analysis, DNA ; Skin Diseases/epidemiology/parasitology/pathology/*veterinary ; Theileria annulata/*isolation & purification ; Theileriasis/epidemiology/parasitology/*pathology