Scimitar syndrome in infancy

OBJECTIVES: The objectives of this study were to determine the anatomic and physiological factors most responsible for the severe symptoms and poor prognosis of infants with scimitar syndrome. BACKGROUND: Whereas the diagnosis of scimitar syndrome is often made incidentally in older children and adults who undergo chest radiography for diverse reasons, infants in whom the diagnosis is made typically present with severe symptoms and have a poor prognosis. METHODS: The clinical, catheterization and imaging data of 13 consecutive infants with scimitar syndrome who underwent cardiac catheterization in the 1st 6 months of life were reviewed, with emphasis on the pulmonary artery pressure, pulmonary and cardiovascular anatomy, therapeutic interventions and outcome. RESULTS: Twelve of the 13 infants had pulmonary hypertension at the time of diagnosis. Six patients died despite specific treatment. Eleven of 13 infants had associated cardiac malformations and 9 had large systemic arterial collateral channels to the right lung. Seven patients had anomalies involving the left side of the heart, especially varying degrees of hypoplasia of the left heart or aorta, and six of these patients died. Ten patients underwent surgical or transcatheter therapy in the 1st year of life. Systemic arteries to the right lung were ligated in three patients and occluded by transcatheter embolization in four. Balloon angioplasty was carried out in two patients, one with stenosis of the left-sided pulmonary veins and one with stenosis of the anomalous right pulmonary vein. The latter had placement of a balloon-expandable stent. In both patients, pulmonary vein stenosis progressed. Six patients had surgical repair of associated cardiovascular anomalies, and two required repair of extracardiac congenital anomalies. Occlusion of the anomalous systemic arteries was generally associated with clinical improvement, but congestive heart failure and pulmonary hypertension recurred in those patients with associated cardiovascular anomalies, whose condition subsequently responded after correction of the shunt lesions. CONCLUSIONS: The severe symptoms and pulmonary hypertension found in infants with scimitar syndrome have many causes. Anomalous systemic arterial supply, pulmonary vein stenosis and associated cardiovascular anomalies play a significant role, and the ultimate outcome of individual infants depends on the feasibility of treating these anomalies in early infancy.     

Knapsack packing networks

A knapsack packing neural network of 4n units with both low-order and conjunctive asymmetric synapses is derived from a non-Hamiltonian energy function. Parallel simulations of randomly generated problems of size n in {5, 10, 20} are used to compare network solutions with those of simple greedy fast parallel enumerative algorithms.     

Ulcerative colitis and total alopecia in a mother and her son

Extraintestinal autoimmune disorders are associated with ulcerative colitis in selected patients and lend support to the theory of immune-mediated injury in inflammatory bowel disease. Rarely, alopecia areata has been associated with ulcerative colitis, and familial aggregation and an HLA association have been reported for both disorders. The occurrence of both alopecia and ulcerative colitis in a mother and son are reported with a detailed investigation of antineutrophil cytoplasmic antibodies and HLA alleles in this family. Treatment with the immunosuppressive agent cyclosporine proved beneficial in the child leading to remission of the ulcerative colitis and nascent growth of scalp and body hair.     

Diffuse neuroendocrine system: structural and functional effects of radiation injury to amine precursor uptake and decarboxylation (APUD) cells

The paper presents a review of the results obtained by the authors on the study of external (gamma) and internal (I-131) radiation effects on the functional morphology and linkage of the diffuse neuroendocrine system (DNES) and amine precursor uptake and decarboxylation (APUD) cells of the stomach and duodenum. The investigations performed enabled us to determine that the morphological changes noted in APUD cells had a dose and time dependency. The present study supports the point of view that the radiation initiates serotonin release from APUD cells, which appears to initiate the mechanism of early postirradiation dysfunctions of the gastrointestinal tract and the subsequent adaptive response of DNES. Analysis of our results, together with a review of the literature, indicates that APUD cells actively participate both in pathogenesis of radiation injury and development of organ and tissue radiosensitivity.     

Structure-cytoprotective activity relationship of simple molecules containing an alpha,beta-unsaturated carbonyl system

In previous reports we attributed the cytoprotective activity of several sesquiterpene lactones to the presence of a nonhindered electrophilic acceptor in their structure. We suggested that the mechanism of protection would be, at least in part, mediated through a reaction between the electrophilic acceptor and the sulfhydryl-containing groups of the mucosa. We report here the gastric cytoprotective effect of simple molecules containing an alpha, beta-unsaturated carbonyl group. In the present paper, we undertake the study of molecular accessibility and molecular shape, in addition to conformational, electronic, and steric factors. Our results helped to establish two important facts connecting chemical structure with cytoprotective effect. Firstly, an adequate molecular accessibility appears to be necessary to produce the biological response, and secondly, the alpha,beta-unsaturated carbonyl system has to be included in a cyclic structure or, at least, in the proximity of a cyclic system.     

Paranasal sinus infection due to atypical mycobacteria in two patients with AIDS

Atypical mycobacteria, which are common opportunistic pathogens in patients with AIDS, have not been previously implicated in the pathogenesis of paranasal sinus infections; we describe two such patients. Clinical and radiographic evidence of bilateral maxillary and ethmoid sinusitis was observed for one patient; his infection proved resistant to therapy with conventional antimicrobials and decongestants. Endoscopic ethmoid sinus biopsy yielded a specimen containing acid-fast bacilli (AFB) that were later identified as Mycobacterium kansasii. Antimycobacterial therapy had not resulted in amelioration of the sinusitis > 2 months later, at which time he died of cerebral toxoplasmosis. The second patient presented with a tender right frontotemporal soft-tissue mass; a computed tomogram disclosed that it extended through the frontal bone to the frontal sinus. Inflamed tissue debrided from the sinus contained AFB; cultures first yielded M. kansasii and later Mycobacterium avium complex. Bacteremia due to both organisms was also demonstrated. Infection progressed despite therapy.     

Survival of patients with congenital diaphragmatic hernia during the ECMO era: an 11-year experience

The pure TdI-1 polypeptide that blocks miniature endplate potentials (MEPPs) and abolishes or reduces endplate potentials (EPPs) below the action potential threshold was identified from the crude fraction of Tityus discrepans venom. The toxin is a potent reversible non-depolarizing muscle relaxant that blocks more than 95% of the EPP at a 2 microM (0.1 mg/ml) concentration. On a molar basis, TdI-1 is as potent as or more potent than many muscle relaxants since, at the concentration used, the toxin suppressed more than 95% of the EPP. Using matrix-assisted laser desorption time of flight (MALD-TOF) ionization mass spectrometry, TdI-1 was found to have an unusally large mol. wt for a scorpion toxin, close to 48,000. The N-terminal sequence of the first 23 residues of TdI-1 was also determined. The fragment differs from the N-terminal sequences of all 140 peptidic scorpion toxins found in the SWISSPROT and PIR databases using the search engine of the felix.EMBL-Heidelberg.de computer (European Molecular Biology Laboratory, Heidelberg, Germany.     

Mechanism of the anti-arrhythmic effect of Rhodiola rosea extract

Critical lower limb ischaemia can occur following rectal surgery by a number of mechanisms. Patients with aorto-iliac stenosis or occlusion may be dependent on collateral circulation to the lower limbs from the visceral arteries supplying the descending colon, sigmoid colon and the rectum. Division of these collaterals can precipitate critical ischaemia of the leg. This is an uncommon scenario but one that should be considered in arteriopaths undergoing rectal surgery. Two cases of this complication are reported and the mechanisms discussed.     

Functional analysis of pVT745, a plasmid from Actinobacillus actinomycetemcomitans

The expansion of myeloma cells is regulated by cytokines, among which IL-6 is a major growth factor. It has been recently suggested that serum transforming growth factor beta 1 (TGF beta 1), a cytokine found in large amounts in alpha-granules of platelets, might play a role in multiple myeloma (MM). It was the purpose of this study to determine serum TGF beta 1 levels in MM patients and to seek a correlation with disease parameters. Measurements were done by ELISA. We studied 35 MM patients (19 stage II, 16 stage III, 20 IgG, 8 IgA and 6 BJ, 1 IgD) in different phases of the disease, 27 healthy individuals and 17 thrombocytopenic patients with other haematological diseases (three MDS, three congenital thrombocytopenia, 11 ITP). Overall samples from MM patients were included: 10 at diagnosis, 18 in remission and 32 in relapse. In normal controls TGF beta 1 serum levels ranged from 1 to 33 ng/ml (median 16.5 ng/ml). In both thrombocytopenic controls with other diseases and thrombocytopenic MM patients (seven samples), TGF beta 1 serum levels were very low (median 3.2 and 4.5 ng/ml respectively). In MM patients with PLT > 100 x 10(9)/L (53 samples), TGF beta 1 serum levels were in the normal range in patients without immunoparesis (1 to 27 ng/ml, median 16.6 ng/ml), whereas they were higher in patients with immunoparesis (polyclonal immunoglobulins (Igs) below lower normal reference values) ranging from 10.2 to 45 ng/ml (median 26.8 ng/ml) (P < 0.01). Serum TGF beta 1 levels fluctuated in the same patient at different times but not according to relapse or remission. Correlation was found only between serum TGF beta 1 levels and immunoparesis and not between serum TGF beta 1 levels and disease stage or Ig subtype nor with prognostic factors for MM (serum CRP, beta 2M or IL-6). This finding suggests that the remaining normal plasma cells are sensitive to the inhibitory action of TGF beta 1 on Ig production. In conclusion TGF beta 1 serum levels are very low in thrombocytopenic patients confirming that platelets are the major source of this cytokine. Furthermore, a strong correlation was found between TGF beta 1 serum levels and immunoparesis in MM patients.