Nonrandom chromosomal gains in pilocytic astrocytomas of childhood.

Low-grade astrocytomas are the most common central nervous system (CNS) tumor occurring in the pediatric age group. Although many of these tumors are karyotypically normal, various studies have reported gains of chromosomes in a significant proportion of cases. We have the opportunity to karyotype two pilocytic astrocytomas occurring in 5- and 15-year-old children.

Non-islet-cell tumor associated with hypoglycemia in a child: successful long-term therapy with growth hormone.

Hypoglycemia occurred in a 2-year-old girl with neuroblastoma. Initially, growth hormone secretion was suppressed, and she had low levels of insulin-like growth factor (IGF)-I and IGF binding protein-3, but elevated levels of large molecular weight IGF-II. We postulated that the pathogenesis of her hypoglycemia involved production of IGF-II by her neuroblastoma, leading to GH suppression and an abnormally elevated ratio of IGF to IGF binding protein.

Acute exertional anterior compartment syndrome in an adolescent female.

Acute compartment syndromes usually occur as a complication of major trauma. While the chronic exertional anterior tibial compartment syndrome is well described in the sports medicine literature, reports of acute tibial compartment syndromes due to physical exertion, or repetitive microtrauma, are rare. The case of an adolescent female who developed an acute anterior compartment syndrome from running in a soccer game is described in this report.

Chromosome aberrations in choroid plexus papillomas.

Karyotypic data on choroid plexus papillomas are scarce and, to date, have revealed no consistent aberrations. We karyotyped a choroid plexus papilloma which was characterized by a stemline of 52,XX, + 7, + 11, + 12, + 12, + 15, + 18. Additional copies of chromosomes 16, 17, and 20 were also observed in a significant proportion of the metaphase cells analyzed.

Familial recurrence of atypical symptoms in an extended pedigree with the syndrome of mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS).

We report a clinically heterogeneous, multigenerational pedigree with the syndrome of mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) associated with a mutation at nucleotide 3243 in the mitochondrial DNA tRNA(Leu)(UUR) gene. Our findings suggest that the mutation at nucleotide 3243 is not always associated with the classic MELAS phenotype and that other symptoms (notably cardiac and gastrointestinal abnormalities) should raise the suspicion of a mitochondrial disorder.

Brachial plexus palsy as a complication of Pavlik harness use.

A 2.75-month-old male infant was referred to our institution due to persistent hip subluxation despite 3 weeks of treatment in a Pavlik harness. Harness treatment was continued for 2 more weeks until it was noted that his left upper extremity function, which had been normal previously, had changed.

A novel mobile element inserted in the alpha spectrin gene: spectrin dayton. A truncated alpha spectrin associated with hereditary elliptocytosis.

Nonviral retrotransposons, retropseudogenes, and short interspersed nuclear elements (SINEs) are mobile DNA segments capable of transposition to new genomic locations, where they may alter gene expression. De novo integration into specific genes has been described in both germ and somatic cells. We report a family with hereditary elliptocytosis and pyropoikilocytosis associated with a truncated alpha-spectrin protein.

Primary structure, ligand binding, and localization of the human type 3 inositol 1,4,5-trisphosphate receptor expressed in intestinal epithelium.

The second messenger, inositol 1,4,5-trisphosphate (InsP3) transduces many hormonal signals which regulate Ca(2+)-dependent processes in the intestinal epithelium. To study the receptors for InsP3 (InsP3Rs), which function as intracellular Ca2+ channels, cDNA clones encoding InsP3Rs were isolated from a human colon adenocarcinoma cell line, HT29. The majority of clones encoded the type 3 InsP3R, the product of the ITPR3 gene on chromosome 6, for which only a 147-amino-acid fragment was known previously (Ozcelik, T.

High-dose steroids prevent placental dysfunction after fetal cardiac bypass.

Surgical treatment of certain congenital heart lesions in utero may have a therapeutic advantage over postnatal repair or palliation. For fetal heart surgery to be possible, a method to support the fetal circulation is necessary. Early experimental attempts at fetal cardiac bypass were unsuccessful because of increased placental vascular resistance during and after fetal cardiac bypass, which led to decreased placental flow, fetal asphyxia, and death.

Spectrin cagliari. an Ala-->Gly substitution in helix 1 of beta spectrin repeat 17 that severely disrupts the structure and self-association of the erythrocyte spectrin heterodimer.

The spectrin tetramer, the principal structural element of the red cell membrane skeleton, is formed by stable head-to-head self-association of two spectrin heterodimers. The self-association site appears to be formed by interactions between helices 1 and 2 of beta spectrin repeat 17 of one dimer with helix 3 of alpha spectrin repeat 1 of the other dimer to form two combined alpha-beta triple-helical segments. The head of the heterodimer appears to involve similar intradimer interactions.

Molecular basis of spectrin deficiency in hereditary pyropoikilocytosis.

Hereditary pyropoikilocytosis (HPP) is a recessively inherited hemolytic anemia characterized by severe poikilocytosis and red blood cell fragmentation. HPP red blood cells are partially deficient in spectrin and contain a mutant alpha or beta-spectrin that is defective in terms of spectrin self-association. Although the nature of the latter defect has been studied in considerable detail and many mutations of alpha-spectrin and beta spectrin have been identified, the molecular basis of spectrin deficiency is unknown.

Isolation of a novel receptor tyrosine kinase cDNA expressed by developing erythroid progenitors.

Activation of distinct receptor tyrosine kinases (RTK), such as the products of the c-fms and c-kit proto-oncogenes, profoundly affects hematopoietic development. We have isolated a novel RTK cDNA, called met-related kinase (MRK), which is expressed on early erythroid progenitors. MRK is also expressed in many hematopoietic cell lines, and is not lineage restricted.

Repair of truncus arteriosus in the neonate.

From September 1986 through December 1991, 63 patients with truncus arteriosus underwent surgical repair. The management approach evolved over the period of the study from elective primary repair at 3 months of age to elective primary repair in the early neonatal period. Thirty variables were examined as potential risk factors for the outcome events of death, reoperation, and presence of pulmonary vascular morbidity.

Structural domain mapping and phosphorylation of human erythrocyte pallidin (band 4.2).

Pallidin (band 4.2) is a major protein of the human erythrocyte membrane, and plays an important but as yet undefined role in maintaining the normal shape and lifespan of the erythrocyte. The pallidin protein has been purified by a new procedure which yields a protein which is > 97% pure as judged by gel electrophoresis, while pallidin purified by our original procedure is only approx.

Biogenesis of erythrocyte membrane skeleton in health and disease.

To study the biogenesis of red cell membrane skeleton at various stages of erythroid differentiation, we have chosen the following model systems: a) Rauscher erythroleukemia cell line representing the early stages of differentiation, b) Friend erythroleukemia cells, and c) in vitro cultured human erythroblasts. The latter two systems represent terminally differentiated erythroblasts. Using these model systems, we have shown asynchronous synthesis of membrane proteins during erythroid differentiation.

Successful management of paraprotein-associated peripheral polyneuropathies by immunoadsorption of plasma with staphylococcal protein A.

Two patients with paraprotein-associated peripheral polyneuropathy were treated successfully using immunoadsorption of patient's plasma with staphylococcal protein A. Both had previously been treated with immunosuppressive agents or plasma exchange, and were rapidly relapsing at the time of their protein A immunoadsorption therapy. One patient was treated "on-line" with a blood cell separator, and one was treated "off-line.

Metastatic breast carcinoma presenting as persistent diarrhea.

Patients with breast carcinoma metastatic to the colon generally present with multiple symptoms, usually pain, vomiting, nausea, and ascites. We describe a patient who presented only with persistent diarrhea, underwent surgery for colon cancer, and, on pathological evaluation of the surgical specimen, was found to have metastatic breast cancer affecting the colon. Metastatic breast cancer should therefore be suspected in patients with a history of breast cancer and diarrhea of unknown cause that is not accompanied by other symptoms.

Prognostic factors in sterile pancreatic necrosis.

Although the overall mortality in sterile pancreatic necrosis is low, patients who experience systemic complications may have a higher mortality. To study the impact of systemic complications and other factors on survival, possible prognostic factors were evaluated among 26 patients who experienced at least one systemic complication. Mortality was 38%.

Noninvasive carotid duplex ultrasound imaging for the evaluation and management of carotid atherosclerotic disease.

Renewed interest in surgical management of atherosclerotic disease of the carotid bifurcation underscores the necessity for accurate and efficacious means for diagnostic evaluation of patients with suspected carotid disease. Noninvasive testing by carotid duplex ultrasound, which combines high-resolution B-mode imaging with pulsed Doppler spectral analysis, is the method of choice. Noninvasive testing permits identification of potentially significant carotid stenosis, occlusion, or unstable plaque morphology with virtually no significant morbidity from the testing itself.

Endometriosis causing colon obstruction in two postmenopausal women.

Colonic endometriosis is an uncommon lesion usually found in premenopausal women. We describe two postmenopausal women with colonic endometriosis that resulted in colonic obstruction. One of the women was receiving estrogen-replacement therapy.

Maturation of murine erythroleukemia cells committed to differentiation requires protein kinase C.

Treatment of murine erythroleukemia cells (MELC) attached to fibronectin-coated dishes with dimethyl sulfoxide causes the cells to become committed to the erythroid differentiation pathway. These cells mature extensively and acquire the characteristics of erythroid cells. The cells lose their cell-surface fibronectin receptors and accumulate red cell-specific membrane proteins, such as band 3, in amounts comparable to those in erythrocytes.