Total arch repair versus hemiarch repair in the management of acute DeBakey type I aortic dissection

Objective: In acute DeBakey type I aortic dissection, it is still controversial whether to perform extended aortic replacement to improve long-term outcome or to use a conservative strategy with ascending aortic and hemiarch replacement to palliate a life-threatening condition. Methods: Between 1999 and 2009, 188 consecutive patients (93 women; mean age, 57.4 ± 11.7 years) with acute DeBakey type I aortic dissection underwent hemiarch (Hemiarch group; n = 144) or total arch replacement (Total arch group; n = 44) in conjunction with ascending aorta replacement. Clinical outcomes were compared after adjustment for baseline characteristics using inverse-probability-of-treatment weighting. Results: Median follow-up was 47.5 months (range 0–130.4 months) and was 92.0% (n = 173) complete. Five-year unadjusted survival and permanent-neurologic-injury-free survival rates were 65.8 ± 8.3% and 43.1 ± 9.7% in the Total arch group, and 83.2 ± 3.3% and 75.2 ± 4.0% in the Hemiarch group, respectively (P = 0.013 and <0.001). After adjustment, the Total arch group patients were at greater risks of death (hazard ratio (HR) 2.38, 95% confidence interval (CI) 1.21–4.67; P = 0.012), and permanent neurologic injury (HR 3.25, 95% CI 1.31–8.04; P = 0.011) compared to the Hemiarch group patients. The risks of the re-operation for aortic pathology or distal aortic dilatation (>55 mm) were similar for both groups (HR 0.33, 95% CI 0.08–1.43; P = 0.14). Conclusions: Total arch repair was associated with greater morbidity and mortality compared with hemiarch repair in acute DeBakey type I aortic dissection. Rates of aortic re-operation or aortic dilatation were not significantly different between the two surgical strategies. These findings support a conservative surgical approach to circumvent this life-threatening situation.     

The Role of Endoscopic Ultrasound in Biliary Obstruction

The role of endoscopic ultrasound (EUS) in the diagnosis of biliary obstruction is well established, and emerging evidence suggests it may also play a therapeutic role. Differentiating between benign and malignant causes of biliary obstruction can be challenging, but EUS is a crucial tool in the armamentarium of the physician. Evolving technologies such as elastography and contrast enhancement may further supplement the diagnostic abilities of EUS. Therapeutic applications of EUS are evolving rapidly, and EUS-guided cholangiography may aid biliary decompression when endoscopic retrograde cholangiopancreatography (ERCP) has failed or is not possible.     

Hodgkin disease: CT of the thymus

The computed tomography (CT) scans in two groups of patients with Hodgkin disease were reviewed to determine the frequency of thymic enlargement. In 50 CT scans from 50 patients with evidence of thoracic disease on CT scans who were examined for primary staging, the thymus was enlarged in 15 of 50 (30%). Fifty CT scans were obtained from 44 patients at the time of 50 separate episodes of known or suspected relapse. Relapse occurred in the mediastinum in 12 episodes, lung parenchyma in five, and both sites in one. Thymic enlargement thought to be due to involvement by disease was present in seven of 18 (38%). Mediastinal disease was associated with thymic enlargement in all but one patient in whom a thymic cyst developed after radiation therapy. Differentiation of thymic enlargement from enlarged superior mediastinal lymph nodes was easily made in all but two patients. Thymic enlargement in the absence of lymph node enlargement may indicate a different disease, since isolated Hodgkin disease of the thymus is uncommon. Primary thymic tumor should be considered initially, whereas after treatment, rebound hyperplasia of the thymus may be the cause of enlargement.     

Deleterious effects of irradiation and bone marrow transplantation therapy in the genetically anemic an/an mouse

The efficacy and outcome of bone marrow transplantation therapy following lethal irradiation were examined in syngeneic mice that had a hereditary macrocytic anemia (an/an) or were genotypically normal (+/+). Successful RBC and WBC replacement, based on blood cell parameters and donor genetic markers, were observed in all combinations of transplant therapy. Nevertheless, the an/an mice died prematurely several months after treatment, whether they received +/+ or an/an marrow cells. In contrast, the +/+ recipients of either +/+ or an/an marrow cells survived for at least 1 year after transplantation. Premature death of the an/an mice was associated with lymphopenia, anemia, kidney lesions, and severe pathogen-free pneumonitis. On the basis of our results, we hypothesize that the premature deaths of an/an mice are caused by a kind of chronic irradiation damage to which an/an mice are especially susceptible.     

Expression of specific granule markers on the cell surface of neutrophil cytoplasts

The widespread assumption that cytoplasts generated from human polymorphonuclear leukocytes (PMNs) are vesicles consisting solely of cytoplasm surrounded by plasma membrane and devoid of granule activity remains to be tested. PMN cytoplasts were prepared by centrifugation of intact cells on a Ficoll step gradient in the presence of cytochalasin B. Two granule membrane markers, Mol, a fluorometrically detectable antigen, and cytochrome b, both of which have been shown to translocate to the plasma membrane during granule release, were compared for their activity in cytoplasts and intact PMNs. We found that the amount of Mol detected on the plasma membrane of intact PMNs, as compared with other membrane markers (such as antigens LFA-1 and beta 2m), increased 1.6- fold upon exposure of PMNs to Ficoll plus cytochalasin B prior to centrifugation. Another twofold increase in Mol expression occurred upon cytoplast preparation. Release of the granule enzymes, vitamin B12- binding protein, and lysozyme were also followed and correlated well (r = .78 and .92) with the amount of Mol antigen present on the cell surface. Cytochrome b was also found to be higher (1.4-fold) on plasma membranes isolated from cytoplasts than on plasma membranes isolated from intact control cells. These results indicate that some fusion of granule membranes and plasma membranes occurred during treatment of PMNs with Ficoll plus cytochalasin b and during cytoplast preparation.     

Myelostimulatory activity of recombinant human interleukin-2 in mice

In a series of studies designed to extend our understanding of interleukin-2 (IL-2) and to study the effect of biologic response modifiers on bone marrow, we observed that administering recombinant human (rH) IL-2 to normal mice resulted in an increase in the frequency of colony-forming units-culture (CFU-C) in bone marrow. In addition, rH IL-2 was able to accelerate host recovery from cyclophosphamide (CTX)- or radiation-induced bone marrow depression and peripheral blood leukopenia. Not only can rH IL-2 accelerate, in a dose-dependent manner, the return of bone marrow, peripheral blood cellularity, and CFU-C frequency to normal levels following cytoreduction by CTX or irradiation, but it also significantly increases CFU-C frequency to greater than normal levels. Furthermore, rH IL-2 can significantly prolong survival of animals receiving a lethal dose of irradiation or CTX. Thus, multiple mechanisms are responsible for the synergistic therapeutic activity associated with rH IL-2 and CTX. rH IL-2 does not act only as an immunomodulatory agent in the presence or absence of suppressor T cells, but also accelerates host recovery from cytoreductive agents, resulting in decreased leukopenia and perhaps resistances to secondary infection. Thus, rH IL-2 plus chemotherapy may increase therapeutic activity against neoplastic disease, not only by adding immune stimulation to the direct antitumor effect of the drug but also by allowing delivery of higher, more effective doses of chemotherapy.     

Five-year clinical outcomes of the first Korean-made sirolimus-eluting coronary stent with abluminal biodegradable polymer

This study evaluated the 5-year clinical outcomes of the Genoss DES, the first Korean-made sirolimus-eluting coronary stent with abluminal biodegradable polymer.We previously conducted the first-in-patient prospective, multicenter, randomized trial with a 1:1 ratio of patients using the Genoss DES and Promus Element stents; the angiographic and clinical outcomes of the Genoss DES stent were comparable to those of the Promus Element stent. The primary endpoint was major adverse cardiac events (MACE), which was a composite of death, myocardial infarction (MI), and target lesion revascularization (TLR) at 5 years.We enrolled 38 patients in the Genoss DES group and 39 in the Promus Element group. Thirty-eight patients (100%) from the Genoss DES group and 38 (97.4%) from the Promus Element group were followed up at 5 years. The rates of MACE (5.3% vs 12.8%, P = .431), death (5.3% vs 10.3%, P = .675), TLR (2.6% vs 2.6%, P = 1.000), and target vessel revascularization (TVR) (7.9% vs 2.6%, P = .358) at 5 years did not differ significantly between the groups. No TLR or target vessel revascularization was reported from years 1 to 5 after the index procedure, and no MI or stent thrombosis occurred in either group during 5 years.The biodegradable polymer Genoss DES and durable polymer Promus Element stents showed comparable low rates of MACE at the 5-year clinical follow-up.