Anomalous Origin of the Left Coronary Artery from the Pulmonary Artery: Diagnoses and Surgical Results in 12 Pediatric Patients

Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital condition. It responds well to early diagnosis and treatment, but otherwise the prognosis is poor. We present our case series of 12 patients (mean age, 2 ± 2.58 yr; age range, 2 mo–8 yr), emphasizing the diagnostic process and discussing our surgical results. The diagnosis of ALCAPA should be suspected in infants who have dilated cardiomyopathy with electrocardiographic changes that suggest ischemia, and in older children who have isolated mitral regurgitation. When clinical suspicion is high, the results of 2-dimensional echocardiography combined with color-flow Doppler studies in expert hands can establish the diagnosis, thus avoiding angiography in critically ill infants. The treatment of choice in our patients was transfer and reimplantation of the left coronary artery onto the ascending aorta. There were 2 deaths: both were infants in extremis who underwent emergency surgery. An older child with severe ventricular dysfunction was given mechanical ventricular assistance and then heart transplantation. As of this report, all 10 survivors remained well and asymptomatic.     

Coronary stenting for coronary artery narrowing in a heart transplant recipient

Transplant atherosclerotic coronary disease remains the leading cause of death in heart transplant recipients. We report the first case of coronary stent implantation in a heart graft for epicardial focal stenosis. Due to the lower rate of restenosis after stenting in the native coronary artery, we suggest that coronary stenting be considered an acceptable, first intention therapeutic option instead of angioplasty alone whenever possible.     

Transplantation for adults with congenital heart disease.

Heart transplantation is a recognised treatment for end-stage heart failure of any cause including congenital heart disease. Congenital heart disease has contributed relatively little to the adult heart transplant activities in the past two decades. However, this is likely to change as an increasing number of children with congenital heart disease reach adulthood because of the advances in paediatric cardiology and surgery. Some of these grown-ups with congenital heart disease (GUCH patients) will need transplantation for late myocardial dysfunction either secondary to uncorrected lesions, or despite previous repair or palliative surgery. These patients are managed along the same clinical principles as those with cardiac failure of other aetiologies, despite the lack of any evidence to support this approach. Nevertheless, they introduce new challenges. First, some may have pulmonary vascular disease and require heart-lung transplantation, or lung transplantation combined with repair of their cardiac defects. Second, those with failing Fontan circulation are usually much sicker than other transplant candidates, with protein-losing enteropathy along with renal and hepatic dysfunction. Third, a suitable donor organ may not be found due to elevated levels of antibodies in response to previous blood transfusions and possibly the previous implantation of homografts. Fourth, the operation may be technically difficult because of the presence of adhesions secondary to previous operations, collaterals, and unusual anatomy. Fifth, postoperative care may be complicated because of predisposition to bleeding, infection and pulmonary hypertension, and the presence of residual aortopulmonary collaterals resulting in a significant left-to-right shunt. Despite a higher early mortality, the overall results of heart transplantation so far have been encouraging with survivals similar to that of adults with acquired heart disease and that of the paediatric population. However, this may change as the proportion of high-risk patients (failing Fontans) increases. GUCH patients with Eisenmenger's syndrome may be offered lung transplantation with repair of the cardiac defect or heart-lung transplantation. However, because of the limited success of these approaches, and improved management of pulmonary hypertension, patient selection remains difficult.     

Proliferation of Nb2 lymphoma cells in vitro in response to interleukin-7.

An attempt was made to investigate the proliferative effect of interleukin-7 (IL-7) on a rat Nb2 T-cell lymphoma line. It was demonstrated that both human and mouse IL-7 stimulated these cells to proliferate in a dose dependent fashion in culture medium containing 10% horse serum. The maximum activities of mIL-7 and hIL-7 were observed at 100 and 1000 units/ml with their half-maximal response of 10 and 50 units/ml, respectively. In a totally serum-free culture condition, mIL-7 produced a similar cellular proliferation, whereas hIL-7 was much less effective. The effectiveness of IL-7 on Nb2 cells was completely abolished by antibody to IL-7, but not by antibody to IL-2. Therefore, Nb2 cells may serve as a simple, convenient and sensitive assay for monitoring the biological activity of IL-7 in vitro. In addition, these cells are also useful for studying the lymphopoiesis of T-cell lineage regulated by IL-7.     

Protective effects of calcium-magnesium soft gels in morphine tolerant and dependent mice.

The present study was aimed at evaluating the acute effects of Calcium-Magnesium soft gels (CalMag) in morphine tolerant and dependent mice. Mice were rendered tolerant and dependent on morphine by subcutaneous injection of morphine over a fixed time period. Withdrawal signs were precipitated by injecting naloxone 2 h after the final injection of morphine. The tail-pinch assay was used to investigate the effects of various compounds on the development and reversal of morphine tolerance. Acute injection of CalMag (containing 50 mg/kg calcium and 25 mg/kg magnesium) significantly reduced the number of jumps, stands and fast breathing in morphine dependent mice. Co-administration of calcium (50 mg/kg) and magnesium (25 mg/kg) was also effective in preventing the development of morphine tolerance and dependence. Administration of calcium (up to 50 mg/kg) alone did not significantly block the development of tolerance and dependence. The mean latency to pain was significantly increased in animals pretreated with CalMag (containing 50 mg/kg calcium and 25 mg/kg magnesium). The mixture of calcium and magnesium at specific concentrations seem to be critical for preventing the development of morphine tolerance and dependence.     

Twelve novel myosin VIIA mutations in 34 patients with Usher syndrome type I: confirmation of genetic heterogeneity

Usher syndrome is a heterogeneous autosomal recessive trait and the most common cause of hereditary deaf-blindness. Usher syndrome type I (USH1) is characterised by profound congenital sensorineural hearing loss, vestibular dysfunction, and prepubertal onset of retinitis pigmentosa. Of the at least six different loci for USH1, USH1B maps on chromosome 11q13, and the MYO7A gene has been shown to be defective in USH1B. MYO7A encodes myosin VIIA, an unconventional myosin, and it consists of 48 coding exons. In this study, MYO7A was analysed in 34 unrelated Usher type I patients by single-strand conformation polymorphism analysis and direct sequencing. We identified a total of 12 novel and unique mutations, all single base changes. In addition, we found a previously reported nonsense mutation (C31X) on nine alleles of a total of six patients from Denmark.     

Hybrid positron detection and optical coherence tomography system: design, calibration, and experimental validation with rabbit atherosclerotic models

We evaluate the performance of our novel hybrid optical coherence tomography (OCT) and scintillating probe, demonstrate simultaneous OCT imaging and scintillating detection, and validate the system using an atherosclerotic rabbit model. Preliminary data obtained from the rabbit model suggest that our prototype positron probe detects local uptake of fluorodeoxyglucose (FDG) labeled with 18F positron (beta) radionuclide emitter, and the high-uptake regions correlate with sites of injury and extensive atherosclerosis areas. Preliminary data also suggest that coregistered high-resolution OCT images provide imaging of detailed plaque microstructures, which cannot be resolved by positron detection.     

CD14lowCD16high: A cytokine-producing monocyte subset which expands during human immunodeficiency virus infection

Infection with the human immunodeficiency virus HIV-1 is associated with the expansion of a CD14^lowCD16^high monocyte subset in peripheral blood. This subset, which represents a minor subpopulation of monocytes in healthy individuals, increases during HIV infection and, in patients with AIDS, may represent up to 40% of the total circulating monocyte cell population. The CD14^lowCD16^high circulating monocytes co-express MAX.1, p150,95 and HLADR which are typical of tissue macrophage markers. These cells also express higher levels of intracellular interleukin (IL)-1α and tumor necrosis factor (TNF)-α than the CD14^highCD16^low monocyte population from the same patients. The CD14^lowCD16^high cells also express low levels of CD35, CD11a and CD4 in common with normal monocytes. When cultured in vitro, monocytes from HIV-seropositive individuals differentiated within a few hours into an elongated fibroblastoid shape characteristic of migratory cells. Our results suggest that the expansion of the CD14^lowCD16^high monocyte subset, which produce high amounts of TNF-α and IL-1α, may participate in the immune dysfunction observed during HIV infection.