Clinical features and management of complete heart block after transaortic extended septal myectomy in patients with hypertrophic obstructive cardiomyopathy / 中华心血管病杂志

<p><b>OBJECTIVE</b>To analyze the clinical features, precaution and management of complete heart block (CHB) after transaortic extended septal myectomy operation (extended Morrow procedure) in patients with hypertrophic obstructive cardiomyopathy (HOCM).</p><p><b>METHODS</b>From October 1996 to December 2011, 10[6 men; mean age (45.4 ± 15.8) years, range 13-60 years] out of 160 consecutive HOCM patients underwent extended Morrow procedure developed CHB postoperatively. Their clinical data were retrospectively analyzed. Baseline transthoracic echocardiography showed that the left ventricular outflow tract (LVOT) gradients was from 68 to 149 (105.1 ± 25.9) mm Hg (1 mm Hg = 0.133 kPa), ECG showed right bundle branch block in 5 patients and atrial fibrillation, atrial premature beats or ST-T segment changes in other 5 patients. Besides extended Morrow procedure, concomitant surgical procedures included mitral valve replacement (MVR) in 2 (2/10) and MVR plus coronary artery bypass grafting in another 2 (2/10) patients. Follow-up data were obtained by subsequent clinic visits in outpatient department and telephone interviews.</p><p><b>RESULTS</b>The in-hospital mortality was 20% (these two patients died of low cardiac output syndrome and multiple organs failure). Four patients underwent MVR simultaneously survived the operation. Postoperative echocardiography demonstrated a reduced LVOT gradient[(13.6 ± 9.7) mm Hg, P < 0.001]. Permanent pacemakers were implanted in all 8 survived patients at 6 days to 7 months after operation. No other severe complications were observed. During follow-up [from 4 to 72 (19.4 ± 22.1) months], there was no death, 1 patient readmitted to our center at 71 months post operation to change the pacemaker because of low voltage of previously implanted pacemaker. Physical capacity and quality of life improved significantly post operation in these 8 patients. The NYHA functional class remained at I-II post operation and during follow up.</p><p><b>CONCLUSIONS</b>CHB is a severe complication after extended Morrow procedure for patients with HOCM and timely permanent pacemaker implantation is mandatory for patients with post procedure CHB.</p>

Intramammary expression and therapeutic effect of a human lysozyme-expressing vector for treating bovine mastitis / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

To develop a gene therapy strategy for treating bovine mastitis, a new mammary-specific vector containing human lysozyme (hLYZ) cDNA and kanamycin resistance gene was constructed for intramammary expression and clinical studies. After one time acupuncture or intracisternal infusion of healthy cows with 400 microg of the p215C3LYZ vector, over 2.0 microg/ml of rhLYZ could be detected by enzymatic assay for about 3 weeks in the milk samples. Western blotting showed that rhLYZ secreted into milk samples from the vector-injected cows had molecular weight similar to that of the natural hLYZ in human colostrums. Twenty days after the primary injection, the quarters were re-injected with the same vector by quarter acupuncture and even higher concentrations of rhLYZ could be detected. Indirect competitive ELISA of milk samples showed that the vector injection did not induce detectable humoral immune response against hLYZ. Clinical studies showed that twice acupuncture of quarters with the p215C3LYZ vector had overt therapeutic effect on clinical and subclinical mastitis previously treated with antibiotics, including disappearance of clinical symptoms and relatively high microbiological cure rates. These data provide a solid rationale for using the vector to develop gene therapy for treating bovine mastitis.