Replacement of the Descending Thoracic Aorta for Massive Aneurysm in Neonatal Marfan Syndrome

We describe a patient with neonatal Marfan syndrome presenting with massive ascending and descending thoracic aortic aneurysm. Because of rapidly progressive respiratory distress due to tracheobronchial compression, emergency replacement of the descending thoracic aorta with a 12-mm PTFE vascular prosthesis was undertaken at 1 month of age. The postoperative course was complicated by bilateral tension pneumothorax contributing to irreversible respiratory failure. The unique clinico-pathological features and the relevant surgical implications of the case are discussed. (J Card Surg 1994;9:109–114)     

Xenoserum-induced cytolytic "T" cells: polyclonal specificity with an apparent "anti-self" component, and cooperative induction.

Mice were primed in vivo by injection of fetal calf serum (FCS) and their spleen cells were incubated in vitro for 5 days in medium containing 10% FCS. This resulted in the development of cytolytic activity, which was most probably due to "T" cells, since effector cells 1) were sensitive to anti-Thy 1 antiserum or monoclonal antibodies in the presence of complement, 2) were not retained on Ig-anti Ig columns, 3) did not develop from "nude" spleen cells. Further arguments for the T cell nature of these effector cells came from their specificity. Blocking experiments using unlabeled competitor cells demonstrated that FCS-induced cytolysis was polyclonal, with clones recognizing allogeneic or syngeneic determinants possibly related to allo or self H-2. In keeping with polyclonality, cytolysis tested on any given target cell was greatly increased by adding Concanavalin A during the cytolysis test. Experiments were made to investigate whether in particular the anti-self cytolytic activity was directed against FCS determinants. We feel that this possibility, although not formally excluded, was made unlikely. The polyclonal specificity at the effector stage stood in sharp contrast to the serum specificity at the induction stage (reported elsewhere). We demonstrated that these two sets of specificities corresponded to two sets of specific cells. A first population of FCS-primed cells had "promoter" activity, in the sense that it could trigger a second population of "precursor" cells to differentiate into polyclonally cytolytic T cells.     

Genetic polymorphism of NAD(P)H:quinone oxidoreductase is associated with an increased risk of infant acute lymphoblastic leukemia without MLL gene rearrangements.

NAD(P)H:quinone oxidoreductase 1 (NQO1) is a detoxification enzyme that protects cells against oxidative stress and toxic quinones. A polymorphism (C609T) in the gene produces in the heterozygous individuals (C/T) a reduction and in those homozygous for the variant allele (T/T) the abolishment of NQO1 protein activity. To assess whether NQO1 inactivating polymorphism (CT/TT) was a possible risk factor for infant acute lymphoblastic leukemia (iALL), we investigated the distribution of NQO1 genotype in 50 iALL patients, 32 with MLL gene rearrangements (MLL+) and 18 without (MLL-). As controls, 106 cases of pediatric ALL (pALL), and 147 healthy subjects were also studied. Compared to normal controls, the frequency of the low/null activity NQO1 genotypes was significantly higher in the iALL MLL- (72 vs 38%, P=0.006; odds ratio (OR) 4.22, 95% confidence interval (CI) 1.43-12.49), while no differences were observed in iALL MLL+ (44 vs 38%, P=0.553; OR 1.26, 95% CI 0.58-2.74). Similar results were observed when pALL were used as control. Our results indicate that only the iALL patients without MLL rearrangements had a significantly higher frequency of NQO1 genotypes associated with low/null activity enzyme, suggesting a possible role for NQO1 gene as an MLL-independent risk factor, in the leukemogenic process of this subtype of iALL.     

Single-level anterior cervical discectomy and interbody fusion using PEEK anatomical cervical cage and allograft bone

Background  

In an effort to avoid the morbidity associated with autogenous bone graft harvesting, cervical cages in combination with allograft bone are used to achieve fusion. The goal of the current study was to assess the reliability and efficacy of anterior cervical discectomy and interbody fusion (ACDF) using a PEEK anatomical cervical cage in the treatment of patients affected by single-level cervical degenerative disease.     

Seven-year performance of the Edwards Prima Plus stentless valve with the intact non-coronary sinus technique

OBJECTIVES: Late results after stentless aortic valve replacement (AVR) may be jeopardized by progressive aortic dilatation. To define functional outcome using the intact non-coronary sinus technique, all patients operated using the stentless Edwards Prima Plus xenograft were assessed. METHODS: Between January 2000 and August 2007, 154 patients, aged 71 +/- 9 years, underwent stentless AVR using a technique, which replaces the non-coronary sinus and stabilizes two of three commissures. Indication was aortic valve stenosis (AS) in 103 (67%) patients: 33 (21%) had bicuspid valve and four endocarditis. Ninety-six (62%) patients were in NYHA III-IV, and 13 (8%) had LVEF <30%. Associated procedures were required in 59 (38%) patients (CABG, 34; ascending aorta, 22; others 3). Study endpoints were survival, freedom from valve-related events, clinical status, and graft function. RESULTS: There were two hospital and two late deaths during a 48 +/- 19 months (1-92) follow-up (97 +/- 3% survival at seven years). Seven-year freedom from structural failure, nonstructural failure, and endocarditis was 99 +/- 1%, 97 +/- 3%, and 98 +/- 2%. Follow-up NYHA (96 vs ten patients in class III-IV, p = 0.001), and cardiac function (13 vs one patient with LVEF <30%, p = 0.02) were improved. Xenograft performance was satisfactory: 0-2 + aortic insufficiency (AI) in 147 (98%) patients, mean trans-prosthetic pressure gradient 8 +/- 4 (0-25 mmHg). Aortic root diameters were comparable to postoperative values (sinus of Valsalva, 36 +/- 8 vs 35 +/- 9 mm, p = ns; sinotubular junction, 32 +/- 7 vs 34 +/- 8 mm, p = ns). CONCLUSIONS: Stentless AVR with non-coronary sinus replacement affords excellent late outcome and low rate of valve-related events, even in complex patients (bicuspid valve, LV failure, and endocarditis). Aortic root dimensions remain stable over time allowing rewarding xenograft function.