The spermatogonial stem cell (SSCs) is unique in that it is the only cell in the adult male that can contribute genes to a subsequent generation. Permanent modification of the germ cell line may be realized if stem cells could be cultured, transfected with unique genes, and then transplanted into recipient testes. We developed a culture system that supported long-term viability of SSCs. We used...

Lack of permissive and productive cell cultures for the human papillomaviruses (HPVs) has hindered the study of virus-neutralizing antibodies and infection. We developed a cell-free system generating infectious HPV16 pseudovirions. HPV16 L1/L2 capsids, which had been self-assembled in insect cells (Sf9) expressing virion proteins L1 and L2, were disassembled with 2-mercaptoethanol (2-ME), a red...

A novel galactosidase gene (gal3149) was identified from Bacillus velezensis SW5 and heterologously expressed in Escherichia coli BL21 (DE3). The galactosidase, Gal3149, encoded by gal3149 an open reading frame of 1,299 bp, 433 amino acids length. Protein sequence analysis showed that Gal3149 belonged to family 4 glycoside hydrolases (GH4). displayed higher enzyme activity for the substrate 2-n...

objective(s): this study was performed to investigate the effects of mucosal acidification on mrna expression and protein synthesis of cystathionine gamma lyase (cse), cystathionine beta synthase (cbs), and mucosal release of h2s in gastric mucosa in rats. materials and methods:thirty-two rats were randomly assigned into 4 groups (8 in each), including: the control group, hcl (10 mm) treated gr...

To study regulation in vivo of the promoter for the neural cell adhesion molecule, N-CAM, we have used homologous recombination to insert the bacterial lacZ gene between the transcription and translation initiation sites of the N-CAM gene. This insertion disrupts the gene and places the expression of beta-galactosidase under the control of the N-CAM promoter. Animals homozygous for the disrupte...