Geographical differences in the genetic diversity of Helicobacter pylori isolates were examined by analyzing rpoB sequences. An extremely high level of allelic diversity among H. pylori strains was found. The rpoB sequences of Asian and non-Asian (North and South American, European, and South African) strains were found to differ. An amino acid polymorphism (alanine and threonine RpoB types) was found at the 497th residue by deduced amino acid analysis. RpoB with a threonine residue (RpoB Thr ) was uniquely present in East Asian countries, and two-thirds of the H. pylori isolate population in this region was RpoB Thr ; however, this type was rare or absent in Western countries, where RpoB Ala predominated. RpoB Thr strains induced a much larger amount of interleukin-8, a chemokine that plays an important role in chronic inflammation, than RpoB Ala strains in cultured MKN45 cells.
Partial left ventriculectomy (PLV) is regarded as one of the alternatives to heart transplantation for idiopathic dilated cardiomyopathy (d-CMP). Between June 1996 and March 2000, 20 patients underwent left ventricular volume reduction surgery at five major cardiac centers in Korea. PLV was performed in 16 patients with d-CMP and in 1 patient with ischemic CMP. The modified Dor procedure was performed in three patients; two patients with d-CMP and one patient with ischemic CMP. Median age was 35 years (range 3-64 years). There were 13 male and 7 female patients; there were 4 patients in Class III and 16 patients in Class IV. Among the 16 patients in Class IV, 5 patients were inotropic dependent, 2 patients were resuscitated from cardiac arrest or shock in hospital, and 1 patient was treated with intra-aortic balloon pumping. Operative technique for PLV was the same as described by Batista and colleagues. For the modified Dor procedures, the apical left ventricle was opened and a circumferential pursestring suture was placed at the base of both papillary muscles to reduce the diameter of the left ventricle concomitant with mitral annuloplasty. Mitral valve repair was performed in 15 patients and mitral valve replacement was performed in 1 patient. Moderate-to-severe tricuspid regurgitation was noted in 12 patients (with tricuspid annuloplasty in 11 of these patients and replacement in 1 patient). Postoperatively, there were seven operative deaths after PLV and one death after the modified Dor procedure. Cause of death after PLV was right heart failure in four of the seven cases, sepsis in one case, and ventricular tachyarrhythmia in the remaining two cases. After the modified Dor procedure, there was one operative death with left ventricular failure. Postoperatively, mean ventricular end-diastolic dimension markedly decreased from 75.3 mm to 50.9 mm. However, this dimension had increased slightly to 58.2 mm, an average observed 22 months later. Mean left ventricular ejection fraction (LVEF) improved significantly from 20.6% to 33.5% (p < 0.0001), but decreased to 28.5% on average 22 months later (p = 0.058). Eleven patients were discharged from the hospital and followed-up for a mean of 20.2 months (range 1-41 months). During the early postoperative period, most were in good condition. However, heart failure progressed with mitral regurgitation in four patients, two of whom underwent heart transplantation. In conclusion, PLV for d-CMP seems to be an effective alternative surgical procedure to heart transplantation in Korea. The modified Dor procedure may be another alternative to transplantation for left ventricular volume reduction. However, in patients showing progression of heart failure, early intervention with ventricular assist or heart transplantation will be necessary. Also, further studies will be necessary for selection criteria and for prevention of ventricular tachyarrhythmia.
Acute complicated type B aortic dissection (TBAD) is a potentially catastrophic, life-threatening condition. If left untreated, there is a high risk of aortic rupture, irreversible organ or limb damage, or death. Several risk factors have been associated with acute complicated TBAD, including age and refractory hypertension. In the acute phase, even uncomplicated patients are more prone to develop complications if hypertension and pain are left medically untreated. Innovations in stent graft technologies have incrementally improved outcomes since their first use for this condition in 1999, though improvement is needed in mitigating periprocedural complications, adverse events, and mortality. In the past decade, endovascular repair has become the preferred treatment because of its superior outcomes to open repair and medical therapy. The Valiant Captivia Thoracic Stent Graft System is a third-generation endovascular stent graft with advancements in minimally invasive delivery, conformability to the anatomy, and the minimization of adverse sequelae. Herein, this stent graft is briefly reviewed and its 3-year outcomes are presented. Freedom from all-cause and dissection-related mortality was 79.1% and 90.0%, respectively. The Valiant Captivia Stent Graft represents a safe, effective intervention for acute complicated TBAD. Continued surveillance is needed to verify its longer-term durability.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.