PhoP- and GlnR-mediated regulation of metK transcription and its impact upon S-adenosyl-methionine biosynthesis in Saccharopolyspora erythraea.

Background: Erythromycin A (Er A) has a broad antibacterial effect and is a source of erythromycin derivatives. Methylation of erythromycin C (Er C), catalyzed by S-adenosyl-methionine (SAM)-dependent O-methyltransferase EryG, is the key final step in Er A biosynthesis. Er A biosynthesis, including EryG production, is regulated by the phosphate response factor PhoP and the nitrogen response factor GlnR.

RegX3-Mediated Regulation of Methylcitrate Cycle in .

is a global human pathogen that infects macrophages and can establish a latent infection. Emerging evidence has established the nutrients metabolism as a key point to study the pathogenesis of and host immunity. It was reported that fatty acids and cholesterol are the major nutrient sources of in the period of infection.

A novel surgical procedure: scaffold-pulmonary autograft transplantation.

Mitral valve-related operations are easy to perform and show good results, but to prevent severe thromboembolism or a high ratio of prosthetic valve destruction by tissue, lifetime anticoagulant therapy is essential after the operation. Thus, identifying a new type of surgical procedure and prosthetic valve to cure mitral valve diseases is necessary. Pulmonary valve autograft transplantation (Ross II) with the "top hat" transplantation technique was first reported by Ross DN to cure mitral disease.

[Ross procedure in treatment of aortic disease: clinical experience of 15 cases].

Objective: To summarize the clinical experience of Ross procedure in treatment of aorta valve diseases.

Methods: The clinical data of 15 patients with aorta valve diseases, 12 men and 3 women, aged 30 +/- 14, including 13 cases of congenital aorta valve disease, 1 case of senile degenerative aortic valve disease, and 1 case of subacte bacterial endocarditis complicated by aortic stenosis (AS), with the heart function (NYHA) of class II in 11 cases and class III in 4 cases, underwent Ross procedure from October 1994 to September 2002 in Anzhen Hospital. Before operation, ultrasound cardiography showed moderate to severe AS and/or aortic insufficiency (AI) with an average aortic valve annulus diameter (AVD) of 2.