Comparison between Four Types of Buffers for DNA Agarose Gel Electrophoresis

To detect the genome of viruses (in environmental and clinical samples), we use electrophoresis running buffer after PCR reaction. Also, electrophoresis buffers were used widely to separate any DNA molecule. In this paper, we used four types of previously known electrophoresis buffers to compare which is easy for preparation, simple in structure, low cost and good performance in agarose gel electrophoresis. For this, we used two agarose concentration (1%, 2%) and two types of DNA ladder (100 bp, 1 kb) represent both smaller and larger sizes of molecule for each type of buffers, from the result we found in first level both supper buffer and TAE buffer with good performance and in second level we found bicarbonate buffer also with good performance also. Finally, we found the tang buffer cannot pose any electrophoretic activity on DNA agarose gel electrophoresis.

Germ cell apoptosis induced by Ureaplasma urealyticum infection

Aim: To study the effect of Ureaplasma urealyticum (UU) infection on germ cell apoptosis of male rats. Meth-ods: Male rats were infected artificially with UU serotype 8 (T_(960)). Morphological changes of germ cells in the sem-iniferous tubules and the lumen of the epididymides were observed under the light microscope. Fluorescence-conjugatedpolyclonal antibodies to Fas and Fas ligand (FasL) were used to localize Fas and FasL. TUNEL staining of germ cellsand Sertoli cells was performed by the AKPase method. TUNEL-positive rate (% positive cells) and TUNEL-positivearea (area occupied by stained cells) were analysed by KS400 Image Analysis System. The DNA laddering analysiswas performed by agarose gels electrophoresis. Results: In those rats infected with UU; (1) Exfoliated germ cellswere dramatically increased. Many multinucleated giant cells were found in the seminiferous tubules and the lumen ofthe epididymides. (2) The number of TUNEL-positive cells and the TUNEL-positive area were significantly increased.(3) The expression of Fas and FasL in germ cells and Sertoli cells was up-regulated. (4) Discrete bands of fragmentedDNA were found in the testicular cells. Conclusion: In male rats, germ cell apoptosis was increased in UU infec-tion . (Asian J Androl 2001 Sep; 3: 199 - 204)

Designing and Cloning of the Gene Sequence Encoding Silk Fibroin Amorphous Domain

To provide materials used in investigating the relationship between amino acid compositions of silk-like protein, structure, and functions, especially the biological functions, the motif genes encoding the silk fibroin amorphous domain, SGFGPVANGGSGEASSESDFGSSGFGPVANASSGEASSESDFAG(F) were designed and extended using a "head-to-tail" construction strategy. The designed genes were cloned into PSLFA1180FA and multimerized to form structures containing a two-timer, a four-timer, an eight-timer, and a twelve-timer. All the resulting plasmids were digested using the restriction enzyme BamHI and the double-enzymes BglII/HindIII. Restriction enzyme analysis and DNA sequencing revealed the motif was successfully cloned into PSLFA1180FA and multimerized to form a twelve-timer without gene deletion or mutation.