Pulmonary fluorodeoxyglucose uptake in infants of very low birth weight with and without intrauterine inflammation.

OBJECTIVE: We compared early pulmonary (18)fluorodeoxyglucose ((18)FDG) uptake in infants who had very low birth weight with and without exposure to intrauterine inflammation by using positron emission tomography (PET). A secondary goal was to correlate (18)FDG uptake with later death or bronchopulmonary dysplasia. METHODS: Within 72 hours of birth, 22 singleton infants between 25 and 30 weeks of gestation had a thoracic PET scan after intravenous (18)FDG. Influx constants (K(i)) for (18)FDG were determined. Placental histology assessed exposure to intrauterine inflammation. RESULTS: Chorioamnionitis was found in 13 infants. Seven of these infants also had evidence of funisitis. No inflammation was detected in the remaining nine infants. Median (minimum, maximum) thoracic K(I) was 0.008 (0.006, 0.011) mL/min/mL in infants with funisitis, 0.006 (0.002, 0.008) in infants with chorioamnionitis only, and 0.006 (0.001, 0.015) in infants with no evidence of intrauterine inflammation (P=.16). No relation was found between K(i) and later death or bronchopulmonary dysplasia. Cord blood interleukin-6 was elevated in newborns with placental inflammation (P=.014). CONCLUSION: Early thoracic PET scanning for metabolically active inflammatory cells does not differ between infants with and without exposure to intrauterine inflammation. Evidence of early intrapulmonary sequestration of inflammatory cells in some infants without chorioamnionitis points to the complex etiology of postnatal inflammation.

Structure-function analysis of the UDP-N-acetyl-D-galactosamine:polypeptide N-acetylgalactosaminyltransferase. Essential residues lie in a predicted active site cleft resembling a lactose repressor fold.

Mucin-type O-glycosylation is initiated by a family of UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferases (ppGaNTases). Based on sequence relationships with divergent proteins, the ppGaNTases can be subdivided into three putative domains: each putative domain contains a characteristic sequence motif. The 112-amino acid glycosyltransferase 1 (GT1) motif represents the first half of the catalytic unit and contains a short aspartate-any residue-histidine (DXH) or aspartate-any residue-aspartate (DXD)-like sequence. Secondary structure predictions and structural threading suggest that the GT1 motif forms a 5-stranded parallel beta-sheet flanked by 4 alpha-helices, which resembles the first domain of the lactose repressor. Four invariant carboxylates and a histidine residue are predicted to lie at the C-terminal end of three beta-strands and line the active site cleft. Site-directed mutagenesis of murine ppGaNTase-T1 reveals that conservative mutations at these 5 positions result in products with no detectable enzyme activity (D156Q, D209N, and H211D) or <1% activity (E127Q and E213Q). The second half of the catalytic unit contains a DXXXXXWGGENXE motif (positions 310-322) which is also found in beta1,4-galactosyltransferases (termed the Gal/GalNAc-T motif). Mutants of carboxylates within this motif express either no detectable activity, 1% or 2% activity (E319Q, E322Q, and D310N, respectively). Mutagenesis of highly conserved (but not invariant) carboxylates produces only modest alterations in enzyme activity. Mutations in the C-terminal 128-amino acid ricin-like lectin motif do not alter the enzyme's catalytic properties.

Heparin improves gas exchange during experimental acute lung injury in newborn piglets.

Although intrapulmonary fibrin deposition is a pathognomonic feature of acute lung injury, it remains uncertain whether thrombin inhibitors affect clinically important outcomes. We hypothesized that both heparin and antithrombin (AT) concentrate improve gas exchange during experimental respiratory distress syndrome. We also tested whether combination therapy is more beneficial than monotherapy. Forty-eight newborn piglets were randomized within 12 litters to one of four groups in a factorial design: (1) AT; (2) heparin; (3) AT plus heparin; (4) untreated control animals. After lung lavage and 4 h of barovolutrauma, mechanical ventilation was continued for 24 h during which ventilator pressures and inspired oxygen were adjusted to maintain normal blood gases. The arterial/ alveolar oxygen tension ratio (a/A ratio) and the ventilator efficiency index (VEI) at 18 and 24 h were compared by repeated measures analysis of variance (ANOVA). In contrast to our hypothesis, only heparin improved gas exchange, and we found little evidence of an interaction with AT. The a/A ratio was 0.48 +/- 0.27 (mean +/- SD) in the presence of heparin versus 0.33 +/- 0.26 in its absence; p = 0.01. Corresponding VEI was 0.30 +/- 0.12 versus 0.25 +/- 0.14; p = 0.04. Hyaline membrane formation was also decreased in heparin-treated animals (p = 0.02).

Choline acetyltransferase (ChAT) immunoreactivity in paraffin sections of normal and diseased intestines.

There is increasing interest in localizing nerves in the intestine, especially specific populations of nerves. At present, the usual histochemical marker for cholinergic nerves in tissue sections is acetylcholinesterase activity. However, such techniques are applicable only to frozen sections and have uncertain specificity. Choline acetyltransferase (ChAT) is also present in cholinergic nerves, and we therefore aimed to establish a paraffin section immunocytochemical technique using an anti-ChAT antibody. Monoclonal anti-choline acetyltransferase (1.B3.9B3) and a biotin-streptavidin detection system were used to study the distribution of ChAT immunoreactivity (ChAT IR) in paraffin-embedded normal and diseased gastrointestinal tracts from both rats and humans. Optimal staining was seen after 6-24 hr of fixation in neutral buffered formalin and overnight incubation in 1 microgram/ml of 1.B3.9B3, with a similar distribution to that seen in frozen sections. In the rat diaphragm (used as a positive control), axons and motor endplates were ChAT IR. Proportions of ganglion cells and nerve fibers in the intramural plexi of both human and rat gastrointestinal tracts were also ChAT IR, as well as extrinsic nerve bundles in aganglionic segments of Hirschsprung's disease. Mucosal cholinergic nerves, however, were not visualized. In addition, non-neuronal cells such as endothelium, epithelium, and inflammatory cells were ChAT IR. We were able to localize ChAT to nerves in formalin-fixed, paraffin-embedded sections. The presence of ChAT IR in non-neuronal cells indicates that this method should be used in conjunction with other antibodies. Nevertheless, it proves to be a useful technique for studying cholinergic neuronal distinction in normal tissues and pathological disorders.

[18F]fluorodeoxyglucose uptake in neonatal acute lung injury measured by positron emission tomography.

The objective of this study was to evaluate positron emission tomography (PET) of [18F]fluorodexoyglucose (18FDG) uptake as a measure of neonatal acute lung injury. Inasmuch as intrapulmonary sequestration of neutrophils is a hallmark of acute lung injury, quantification of neutrophil activity using 18FDG may offer a novel, in vivo technique to examine the progression and resolution of this disease. Ten newborn piglets were studied: six received bronchoalveolar lavage followed by 4 h of high pressure ventilation of create acute lung injury. Four healthy piglets served as controls. 18FDG (0.8 mCi/kg; 29.6 MBq) was given i.v. and PET (ECAT 953/31, Siemens) was performed for 90 min. During PET, all animals were sedated, paralyzed, and ventilated to maintain normal blood gases. The time course of radioactivity in lung regions and in plasma was used to calculate the rate constant for the metabolic trapping of 18FDG in tissue according to the method of C. S. Patlak. Median 18FDG influx constants were significantly higher in injured piglets (0.0187 min-1) than in control piglets (0.0052 min-1) (p < 0.01). Moreover, consistent with the 18FDG uptake data, injured piglets had moderate to severe injury on lung histology whereas control piglets had only slight and focal histologic changes. We conclude that PET of 18FDG uptake is an accurate, readily repeatable in vivo measure of neonatal acute lung injury.

Thrombin inhibitors reduce intrapulmonary accumulation of fibrinogen and procoagulant activity of bronchoalveolar lavage fluid during acute lung injury induced by pulmonary overdistention in newborn piglets.

We determined whether antithrombin (AT III) or hirudin (a specific thrombin inhibitor) reduce both the accumulation of fibrinogen in lung parenchyma and the procoagulant activity of bronchoalveolar lavage (BAL) fluid during acute lung injury induced by pulmonary overdistention. Newborn piglets were randomized to six-hourly infusions of AT III concentrate, a continuous infusion of recombinant hirudin, or no anticoagulant therapy. All animals were subjected to 24 h of identical mechanical ventilation at high peak pressures (3.9 kPa or 40 cm H2O). Tidal volumes were raised to a mean of 69 mL/kg in all three groups. Mean AT III levels in supplemented piglets (n = 22) were increased to 1.46 (SD 0.24) U/mL at 24 h, compared with 0.67 (SD 0.16) U/mL in controls (n = 23). The median activated partial thromboplastin time in animals receiving hirudin (n = 18) was prolonged to 53 s versus 34 s in untreated animals. The intrapulmonary accumulation of i.v. administered 125I-fibrinogen was reduced by AT III concentrate or hirudin, compared with untreated littermates (p = 0.003). The procoagulant activity of BAL fluid was also decreased by both thrombin inhibitors (p = 0.001). Intrapulmonary accumulation of fibrinogen and the procoagulant activity of BAL fluid were reduced by AT III or hirudin during lung injury caused by pulmonary overdistention. Future investigations should determine whether tangible clinical benefits result from this reduced potential for fibrin deposition in the injured lung.

Comparison of the prognostic significance of the Shimada classification and N-myc copy number in neuroblastoma.

This report outlines the experience with the first 20 patients (8 males and 12 females) enrolled in the Canadian National Neuroblastoma Diagnostic Laboratory, The study population ranged in age at diagnosis from one month to 11 years. Fourteen children had advanced (stage 3 or 4) disease. Tumors were sampled extensively and were classified, at the time of accession, according to the 'Shimada' histopathological scheme. A portion of each tumor was analyzed for N-myc oncogene copy number. Nine tumors were classified as having 'favourable' histopathological features and 11 as 'unfavourable'. N-myc oncogene amplification, of 3 or more copies, was found in 2 of 9 tumors with 'favourable' histology and 5 of 11 with 'unfavourable' features. The follow-up interval was at least two years from initial diagnosis. The Shimada classification was more accurate than the N-myc oncogene copy number (p<0.01) in predicting clinical outcome. The sensitivity and specificity for Shimada histopathological classification were 100% and 92% respectively, while corresponding values were 75% and 42% for N-myc copy number. Our experience indicates that, when assessing prognosis in neuroblastoma, Shimada classification performs better than the N-myc copy number.

Epstein-Barr virus in non-Hodgkin's lymphomas and lymphoid tissue in children.

In developed countries the majority of adolescent children show serological evidence of past Epstein-Barr virus (EBV) infection. This virus is associated with non-Hodgkin's lymphomas in immunocompromised children, but the relationship of EBV DNA to these tumors in children without documented immunodeficiency has not been investigated by the polymerase chain reaction (PCR). We used a PCR method with primers from the Bam W and Bam HI regions to study non-Hodgkin's lymphomas in children, with tonsillar tissue of age-matched children as controls for the presence of EBV DNA. Six of the 20 tonsils were positive using the Bam W primers; another four showed this DNA with Bam HI primers. EBV DNA was detected in only one tumor (a lymphoblastic lymphoma) by both primer sets. The demonstration of EBV DNA in the tonsils reflects past infections and the incidence is in accordance with that expected from serologic epidemiological studies. The absence of demonstrable EBV DNA in 19 lymphomas suggests that this virus is of little consequence in the pathogenesis of non-Hodgkin's lymphomas in children who are not known to be immunocompromised. The lymphoblastic lymphoma had a mixed cell population, and the virus was not necessarily related to the malignancy.

Xanthoma disseminatum in an infant with skeletal and marrow involvement.

PURPOSE: Xanthoma disseminatum is a rare non-Langerhans' histiocytosis of older children and adults with characteristic lesions involving the skin, mucous membrane and occasionally internal organs. We describe a case, presenting in infancy, with unique clinical features. PATIENT AND METHODS: The patient presented at 8 months of age with skin lesions subsequently found to have histologic, immunophenotypic, and ultrastructural characteristics of non-Langerhans' histiocytosis. In addition to extensive skin lesions, the patient also has involvement of the buccal mucosa, lips, eyelids, bones, bone marrow, and possibly liver and spleen. RESULTS: Clinical and pathological features of the patient are suggestive of xanthoma disseminatum. Treatment with cytotoxic, immunomodulatory, and lipid-lowering agents has been unsuccessful to date. CONCLUSION: Unique characteristics of this case of xanthoma disseminatum include the patient's young age, lytic bone lesions, and previously undescribed bone marrow involvement.

Hypothesis: pathogenesis of skip areas in long-segment Hirschsprung's disease.

The existence of skip areas in a subset of patients with long-segment Hirschsprung's disease (LSHD) is a rare phenomenon that poses practical and theoretical challenges. In this paper, three new cases are described and compared with preceding reports in the medical literature. In addition, an analogous distribution of ganglion cell precursors is reported in the developing large intestines of murine embryos, homozygous for the lethal spotted (ls) allele. In ls/ls embryos, which were destined to have "classic" short-segment aganglionosis coli, a transient phase was observed in which ganglion cells were present in the middle colon, but absent from the cecum and distal large intestine. This "skip area" is attributed to an extramural phase of neuroblast migration which is unique to the colon. Persistence of an abnormal pattern of neuroblast migration, similar to that observed transiently in ls/ls embryos, is invoked as an explanation for skip areas in humans with LSHD.

Yersinia enterocolitica infection with ileal perforation associated with iron overload and deferoxamine therapy.

Despite the frequency of gastrointestinal disease caused by Yersinia enterocolitica, intestinal perforation is a rare complication of this infection and to date only eight cases have been reported in the English literature. We describe a case of this unusual condition in a 17-year-old male patient with thalassemia intermedia requiring transfusion, who was also taking deferoxamine. The severity of the clinical picture is probably due to the increased virulence of Yersinia enterocolitica in the presence of deferoxamine and iron.

Cervical cystic hygroma in the fetus: clinical spectrum and outcome.

Cervical cystic hygroma is thought by most pediatric surgeons to be an isolated, usually resectable lesion with an excellent prognosis. However, prenatal sonography has revealed a high "hidden mortality" among fetuses with this condition, and most perinatologists consider it to be uniformly fatal. In an attempt to resolve these two differing perspectives, we analyzed 29 cases seen at two centers over 4 years. Of 27 fetuses diagnosed before 30 weeks' gestation, only one survived. Twenty-five of the 27 were aborted; severe hydrops was present in 21 of these 25. Two of the 27, both with stigmata of Noonan's syndrome, underwent spontaneous regression during the second trimester: one died at 2 weeks of age, and the other survived. Successful karyotypes were obtained on 17 fetuses: nine were normal, seven were 45X, and one was trisomy 21. Fetuses with abnormal karyotypes had a lower incidence of polyhydramnios (0% v 67%), additional anomalies (12% v 67%), and consanguinity or a history of abnormal pregnancies (0% v 89%). Two fetuses were diagnosed after 30 weeks' gestation. Neither had hydrops, polyhydramnios, associated anomalies, or an abnormal karyotype. One had a completely normal sonogram at 17 weeks' gestation. Both were operated on within the first 4 days of life; one did well without complications, and the other required a permanent tracheostomy because of extensive hypopharyngeal involvement. A cystic hygroma presenting in the fetus has a different natural history and prognosis from one presenting postnatally. The vast majority of fetal cases are diagnosed before 30 weeks' gestation, and present with hydrops or diffuse lymphangiomatosis. The dismal outlook in this group justifies elective termination in most cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Myocardial failure and shock in iron poisoning.

Shock is a well-known complication of iron poisoning. Its aetiology is multifactorial with hypovolaemia due to gastrointestinal blood loss and myocardial depression due to systemic acidosis contributing to its genesis. Primary myocardial dysfunction has not been considered to play a role. Our clinical experiences and autopsy findings in three fatal cases of iron poisoning support myocardial dysfunction and damage as contributing factors to their cardiovascular collapse. The three patients, all female, were 3 1/2, 16 and 28-years-old. Onset of shock occurred at 1, 2 and 5 days post-ingestion. There was no response to vigorous fluid replacement therapy and aggressive catecholamine infusions. Central venous pressures were elevated. Microscopic examination of postmortem tissue showed myocardial damage and the presence of stainable iron. It is speculated that the myocardial depression is mediated by lipid peroxidation of myocyte organelle membranes due to iron catalysed free radical generation. The presence of myocardial dysfunction has therapeutic implications. Patients with severe iron poisoning require early and serial measurements of arterial blood pressure, central venous pressure and cardiac output. If primary myocardial dysfunction is documented then fluid replacement, inotropic support and afterload reduction should be considered.

A new autosomal recessive lethal chondrodystrophy with congenital hydrops.

Two sibs, the offspring of consanguineous parents, presented with severe short-limb dwarfism and distinct chondro-osseous, radiologic, and histologic appearance. The first sib presented at 30 wk with severe hydrops following fetal death; the second was detected by ultrasonography at 20 wk. Radiologic abnormalities included an unusual "moth-eaten" appearance of the markedly short long bones, bizzare ectopic ossification centers, and marked platyspondyly with unusual ossification centers. Marked extramedullary erythropoiesis was present in both fetuses, and chondro-osseous histology was characterized by marked disorganization of tissue with interspersed masses of cartilage, bone, and mesenchymal tissue. These sibs appear to have a distinct previously unreported autosomal recessive skeletal dysplasia, which can present as hydrops fetalis.

Demonstration of Epstein-Barr virus in immunoblastic sarcoma of B-cells arising in a child with primary immunodeficiency disease.

The subject of this investigation was an 11-month-old infant girl who presented with a pathological fracture of the right femur due to a metastasis from an abdominal immunoblastic sarcoma. Her past history included recurrent, intractable bacterial and fungal infections. Investigations of her immune status revealed low numbers of T-lymphocytes, a reversed T-helper (TH)/T-suppressor (TS) cell ratio, no response of her peripheral blood lymphocytes to pokeweed mitogen, phytohemagglutinin, concanavalin A, and Candida albicans, and an inability of her cells to react in a mixed lymphocyte culture. Serum levels of IgG, IgM, and IgA were all below normal. No thymic shadow was visible on the chest radiograph. There was no evidence of adenosine deaminase or nucleoside phosphorylase deficiencies. The tumor cells exhibited both surface IgM and IgG, and many of the cells contained large amounts of cytoplasmic IgM. Light chain specificity was restricted to lambda chain for both surface and cytoplasmic immunoglobulin. Ultrastructural study of the tumor cells revealed the presence of both intranuclear and cytoplasmic virions in roughly 1% of the tumor cells. These viral particles strongly resembled herpes viruses. DNA-hybridization studies on the neoplasm revealed the presence of 7-10 genome equivalents of Epstein-Barr virus-DNA per tumor cell.

Congenital ependymoblastoma presenting as a sacrococcygeal mass in a newborn: an immunohistochemical, light and electron microscopic study.

We describe a case of congenital ependymoblastoma presenting as a subcutaneous mass in the sacrococcygeal area of a newborn male. The tumor was composed of primitive cells disposed in compact sheets and cords and exhibiting focal ependymal differentiation. No other line of cellular differentiation was identified by either immunohistochemistry or ultrastructural study. Elevated serum alpha-fetoprotein was found, which decreased following surgical extirpation of the tumor. We propose that this tumor had its origin in the ependymal medullary vestige, similar to other sacrococcygeal ependymomas.

An autosomal dominant form of adolescent multinodular goiter.

Eighteen members of an extended pedigree have been found to have a form of euthyroid adolescent multinodular goiter. Histological examination showed multiple adenomata with areas of epithelial hyperplasia, hemorrhage, and calcification. In two subjects there were focal areas of epithelial hyperplasia reminiscent of low-grade papillary carcinoma, but capsular and vascular invasion was not found. The pattern of inheritance appeared to be autosomal dominant, with diminished penetrance in males. Although the patients were euthyroid, the likely basis for this disorder is an abnormality in thyroglobulin structure and function.

Metastatic osteosarcoma and multiple lung resection. A case report.

The existence of pulmonary metastases in patients presenting with osteosarcoma is known to indicate a poor prognosis. Lung resection of solitary lesions is now a standard treatment approach, but with limited successful long-term results. We report the progress of a 16-year-old girl with osteosarcoma of the proximal tibia who underwent 11 lung resections for pulmonary metastases over a two-year period, and who has since then been free of disease for seven years.