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Supplementing an earlier analysis of event-related potentials in extensive motor learning (Margraf et al., 2022a, 2022b), frontal theta-band activity (4-8 Hz) was scrutinized. Thirty-seven participants learned a sequential arm movement with 192 trials in each of five practice sessions. Feedback, based on a performance adaptive bandwidth, was given after every trial. Electroencephalogram (EEG) was recorded in the first and last practice sessions. The degree of motor automatization was tested under dual-task conditions in a pre-test-post-test design. Quantitative error information was transported in both feedback conditions (positive and negative). Frontal theta activity was discussed as a general signal that cognitive control is needed and, therefore, was expected to be higher after negative feedback. Extensive motor practice promotes automatization, and therefore, decreased frontal theta activity was expected in the later practice. Further, it was expected that frontal theta was predictive for subsequent behavioural adaptations and the amount of motor automatization. As the results show, induced frontal theta power was higher after negative feedback and decreased after five sessions of practice. Moreover, induced theta activity was predictive for error correction and, therefore, an indicator of whether the recruited cognitive resources successfully induced behavioural adaptations. It remains to be solved why these effects, which fit well with the theoretical assumptions, were only revealed by the induced part of frontal theta activity. Further, the amount of theta activity during practice was not predictive for the degree of motor automatization. It seems that there might be a dissociation between attentional resources associated with feedback processing and attentional resources associated with motor control., (© 2023 The Authors. European Journal of Neuroscience published by Federation of European Neuroscience Societies and John Wiley & Sons Ltd.)

Several event-related potentials (ERPs) are associated with the processing of valence-dependent augmented feedback during the practice of motor tasks. In this study, 38 students learned a sequential arm-movement-task with 192 trials in each of five practice sessions (960 practice trials in total), to examine practice-related changes in neural feedback processing. Electroencephalogram (EEG) was recorded in the first and last practice session. An adaptive bandwidth for movement accuracy led to equal amounts of positive and negative feedback. A frontal located negative deflection in the time window of the feedback-related negativity (FRN) was more negative for negative feedback and might reflect reward prediction errors in reinforcement learning. This negativity increased after extensive practice, which might indicate that smaller errors are harder to identify in the later phase. The late fronto-central positivity (LFCP) was more positive for negative feedback and is assumed to be associated with supervised learning and behavioral adaptations based on feedback with higher complexity. No practice-related changes of the LFCP were observed, which suggests that complex feedback is processed independent from the practice phase. The P300 displayed a more positive activation for positive feedback, which might be interpreted as the higher significance of positive feedback for the updating of internal models in this setting. A valence-independent increase of the P300 amplitude after practice might reflect an improved ability to update the internal representation based on feedback information. These results demonstrate that valence-dependent neural feedback processing changes with extensive practice of a novel motor task. Dissociating changes in latencies of different components support the assumption that they are related to distinct mechanisms of feedback-dependent learning., (Copyright © 2021 IBRO. Published by Elsevier Ltd. All rights reserved.)

To examine the neural processing of valence-dependent augmented feedback, 38 students learned a sequential arm movement task with 192 trials in each of five practice sessions. The degree of motor automatization was tested under dual-task-conditions. Electroencephalogram (EEG) was recorded in the first and last practice session. This study is an additional analysis of the data from Margraf et al. [Margraf, L., Krause, D., & Weigelt, M. (this issue). Valence-dependent neural correlates of augmented feedback processing in extensive motor sequence learning - Part I: Practice-related changes of feedback processing.]. While Part I focused on changes in neural feedback processing after extensive motor practice, Part II examines coherences between neural feedback processing and short-term behavioral adaptations, as well as different dimensions of long-term learning (i.e., accuracy, consistency, and automaticity). It was found that more negative amplitudes of the feedback-related-negativity (FRN) after negative feedback were predictive for goal-independent changes of behavior in the early practice phase, whereas more positive amplitudes of the late fronto-central positivity (LFCP) after negative feedback were predictive for goal-directed behavioral adaptations (error reduction), independent from the practice phase. Unexpectedly, more positive amplitudes of the P300 after positive feedback were also predictive for goal-directed behavioral adaptations. Concerning long-term learning and motor automatization, a positive correlation was found for the reduction of dual-task costs (DTC) and LFCP-amplitudes after positive feedback in the early practice., (Copyright © 2021 IBRO. Published by Elsevier Ltd. All rights reserved.)

Pleuropulmonary blastoma (PPB) is a rare malignancy of childhood which when left untreated often shows pathologic progression resulting in a more aggressive neoplasm with an increasingly poor prognosis. Because of this it is important to diagnose and initiate treatment early. However, early stage PPB can appear as a cystic lung lesion on imaging and can be easily misdiagnosed given the rarity of the malignancy. Moreover, current therapeutic guidelines for these lesions are not well established, making treatment decisions and management difficult for clinicians. DICER1 mutations are known to be present in a majority of PPBs with or without a germline mutation and may be part of a familial tumor predisposition syndrome. The clinical, pathologic, and genetic data of 6 patients are summarized here. Two patients with type I PPB and 4 patients with type II PPB underwent surgical and chemotherapeutic treatment and all are alive and without recurrence 1 to 13 years after treatment. With increasing awareness of PPB, it is important for clinicians to consider this malignant entity in the evaluation and treatment of patients presenting with a cystic lung abnormality, especially in cases with a history strongly suggestive of a DICER1 mutation.

Objective: This single-blind controlled study evaluated the genotoxicity and efficacy of at-home bleaching in smokers and nonsmokers., Methods: We selected 60 patients with central incisors A2 or darker: 30 smokers (experimental group) and 30 nonsmokers (control group). The bleaching was carried out with 10% carbamide peroxide for three hours a day for three weeks. The color was evaluated using a shade guide, Vita Bleachedguide 3D-Master, at baseline, during bleaching (first, second, and third weeks), and one week and one month after bleaching. Smears were obtained with a moistened wooden spatula from marginal gingiva. All the cytologic smears were stained with Giemsa solution. From each slide, 1000 cells were examined under 40× magnification and where micronuclei (MN) were located, they were examined under 100× magnification. The change in shade guide units at the different assessment periods and the frequency of MN were subjected to a two-way repeated measures analysis of variance and Tukey test (α=0.05)., Results: In both groups we detected a whitening of approximately 4 to 5 shade guide units, without color rebound after one month (p>0.05). The frequency of MN was significantly higher in the experimental group than in the control group, regardless of the bleaching treatment (p>0.001)., Conclusion: The efficacy of bleaching does not appear to be affected by the smoking habit. Additionally, at-home bleaching did not induce DNA damage to the gingival tissue during the bleaching period.

Background and Purpose: Pleomorphic xanthoastrocytomas are rare astrocytic neoplasms of childhood and young adulthood. The purpose of this retrospective review was to evaluate MR imaging features of pediatric pleomorphic xanthoastrocytomas with an emphasis on diffusion MR imaging., Materials and Methods: Review of the neuro-oncology data base revealed 11 pediatric patients (range, 4.7-16.1 years) with pleomorphic xanthoastroacytomas with 9 of these patients having preoperative MR imaging available. Six patients had preoperative diffusion MR imaging. Demographics, histopathology slides, conventional imaging characteristics (location, cystic component, hemorrhage, enhancement, vasogenic edema, inner table scalloping), and ADC metrics (mean tumor ADC and tumor to normal brain ADC ratio) were evaluated., Results: Three pleomorphic xanthoastrocytomas had anaplastic features. Ten tumors were supratentorial. Two-thirds (6 of 9) of all tumors were either predominantly cystic or had cystic components, and three-fourths (6 of 8) of the supratentorial tumors had associated inner table scalloping. Seven of the 9 tumors had marked vasogenic edema (>10 mm). Mean tumoral ADC (n = 7) was 912 ± 219 × 10(-6) mm(2)/s (min-max: 617-1189). The tumor to normal brain ADC ratio was 1.14 ± 0.26 (min-max: 0.75-1.47)., Conclusions: Pleomorphic xanthoastrocytoma should be entertained in the differential diagnosis of peripheral supratentorial tumors that appear during childhood. Cysts, inner table scalloping, and marked vasogenic edema are relatively frequent features. Relatively low ADC values and ADC ratios are not uncommon in pleomorphic xanthoastrocytoma., (© 2014 by American Journal of Neuroradiology.)

Background: The aim of this study was to assess outcomes of medical and surgical treatment of intratonsillar abscess in children., Methods: The medical charts of children with intratonsillar abscess were reviewed to obtain information on history and physical examination, imaging, management, and follow-up assessment., Results: Eleven children (six male, five female; age range, 4-18 years) were identified. The common complaints included sore throat, fever, and odynophagia. Asymmetric tonsil hypertrophy was present in nine patients and erythema of tonsils in all patients. Peritonsillar fullness was present in three patients. One patient needed emergency intubation due to respiratory compromise. Computed tomography indicated unilateral intratonsillar abscess in nine patients, bilateral intratonsillar abscess in one, and unilateral phlegmon in one. Inflammatory changes were observed in the parapharyngeal space in all patients, retropharyngeal space in one, and pyriform sinus and aryepiglottic folds in two. Antibiotic treatment included clindamycin in seven patients, ampicillin/sulbactam in one, and clindamycin plus ceftriaxone in three. The patients with respiratory compromise underwent surgery prior to antibiotic treatment. Patients with isolated intratonsillar abscess or phlegmon had resolution of their symptoms with i.v. antibiotic treatment. Patients with combination of intratonsillar and peritonsillar abscess required incision and drainage of peritonsillar abscess., Conclusions: Clinically stable children with intratonsillar abscess or phlegmon respond to i.v. antibiotic therapy. Surgical drainage can accomplish clinical resolution in the presence of a combination of intra- and peri-tonsillar abscess, airway compromise, or unresponsiveness to medical treatment., (© 2013 The Authors. Pediatrics International © 2013 Japan Pediatric Society.)

Purpose: To test whether there is correlation between cell densities and apparent diffusion coefficient (ADC) metrics of common pediatric cerebellar tumors., Materials and Methods: This study was reviewed for issues of patient safety and confidentiality and was approved by the Institutional Review Board of the University of Texas Southwestern Medical Center and was compliant with HIPAA. The need for informed consent was waived. Ninety-five patients who had preoperative magnetic resonance imaging and surgical pathologic findings available between January 2003 and June 2011 were included. There were 37 pilocytic astrocytomas, 34 medulloblastomas (23 classic, eight desmoplastic-nodular, two large cell, one anaplastic), 17 ependymomas (13 World Health Organization [WHO] grade II, four WHO grade III), and seven atypical teratoid rhabdoid tumors. ADCs of solid tumor components and normal cerebellum were measured. Tumor-to-normal brain ADC ratios (hereafter, ADC ratio) were calculated. The medulloblastomas and ependymomas were subcategorized according to the latest WHO classification, and tumor cellularity was calculated. Correlation was sought between cell densities and mean tumor ADCs, minimum tumor ADCs, and ADC ratio., Results: When all tumors were considered together, negative correlation was found between cellularity and mean tumor ADCs (ρ = -0.737, P < .05) and minimum tumor ADCs (ρ = -0.736, P < .05) of common pediatric cerebellar tumors. There was no correlation between cellularity and ADC ratio. Negative correlation was found between cellularity and minimum tumor ADC in atypical teratoid rhabdoid tumors (ρ = -0.786, P < .05). In atypical teratoid rhabdoid tumors, no correlation was found between cellularity and mean tumor ADC and ADC ratio. There was no correlation between the ADC metrics and cellularity of the pilocytic astrocytomas, medulloblastomas, and ependymomas., Conclusion: Negative correlation was found between cellularity and ADC metrics of common pediatric cerebellar tumors. Although ADC metrics are useful in the preoperative diagnosis of common pediatric cerebellar tumors and this utility is generally attributed to differences in cellularity of tumors, tumor cellularity may not be the sole determinant of the differences in diffusivity.

Alveolar capillary dysplasia with misalignment of pulmonary veins (ACD/MPV) is a rare and lethal developmental disorder of the lung defined by a constellation of characteristic histopathological features. Nonpulmonary anomalies involving organs of gastrointestinal, cardiovascular, and genitourinary systems have been identified in approximately 80% of patients with ACD/MPV. We have collected DNA and pathological samples from more than 90 infants with ACD/MPV and their family members. Since the publication of our initial report of four point mutations and 10 deletions, we have identified an additional 38 novel nonsynonymous mutations of FOXF1 (nine nonsense, seven frameshift, one inframe deletion, 20 missense, and one no stop). This report represents an up to date list of all known FOXF1 mutations to the best of our knowledge. Majority of the cases are sporadic. We report four familial cases of which three show maternal inheritance, consistent with paternal imprinting of the gene. Twenty five mutations (60%) are located within the putative DNA-binding domain, indicating its plausible role in FOXF1 function. Five mutations map to the second exon. We identified two additional genic and eight genomic deletions upstream to FOXF1. These results corroborate and extend our previous observations and further establish involvement of FOXF1 in ACD/MPV and lung organogenesis., (© 2013 Wiley Periodicals, Inc.)

Pediatric low-grade gliomas (PLGGs) are among the most common solid tumors in children but, apart from BRAF kinase mutations or duplications in specific subclasses, few genetic driver events are known. Diffuse PLGGs comprise a set of uncommon subtypes that exhibit invasive growth and are therefore especially challenging clinically. We performed high-resolution copy-number analysis on 44 formalin-fixed, paraffin-embedded diffuse PLGGs to identify recurrent alterations. Diffuse PLGGs exhibited fewer such alterations than adult low-grade gliomas, but we identified several significantly recurrent events. The most significant event, 8q13.1 gain, was observed in 28% of diffuse astrocytoma grade IIs and resulted in partial duplication of the transcription factor MYBL1 with truncation of its C-terminal negative-regulatory domain. A similar recurrent deletion-truncation breakpoint was identified in two angiocentric gliomas in the related gene v-myb avian myeloblastosis viral oncogene homolog (MYB) on 6q23.3. Whole-genome sequencing of a MYBL1-rearranged diffuse astrocytoma grade II demonstrated MYBL1 tandem duplication and few other events. Truncated MYBL1 transcripts identified in this tumor induced anchorage-independent growth in 3T3 cells and tumor formation in nude mice. Truncated transcripts were also expressed in two additional tumors with MYBL1 partial duplication. Our results define clinically relevant molecular subclasses of diffuse PLGGs and highlight a potential role for the MYB family in the biology of low-grade gliomas.

Germ-cell tumors (GCTs), which arise from pluripotent embryonic germ cells, exhibit a wide range of histologic differentiation states with varying clinical behaviors. Although testicular GCT is the most common cancer of young men, the genes controlling the development and differentiation of GCTs remain largely unknown. Through a forward genetic screen, we previously identified a zebrafish mutant line, tgct, which develops spontaneous GCTs consisting of undifferentiated germ cells [Neumann JC, et al. (2009) Zebrafish 6:319-327]. Using positional cloning we have identified an inactivating mutation in alk6b, a type IB bone morphogenetic protein (BMP) receptor, as the cause of the zebrafish GCT phenotype. Alk6b is expressed in spermatogonia and early oocytes, and alk6b mutant gonads display impaired BMP signal transduction, altered expression of BMP target genes, and abnormal germ-cell differentiation. We find a similar absence of BMP signaling in undifferentiated human GCTs, such as seminomas and embryonal carcinoma, but not in normal testis or in differentiated GCTs. These results indicate a germ-cell-autonomous role for BMP signal transduction in germ-cell differentiation, and highlight the importance of the BMP pathway in human GCTs.

Recurrent ependymomas are considered rarely responsive to chemotherapy and often have a dismal prognosis after tumor progression. Below is a brief report of a 6 year old child with a multiply progressive ependymoma whose tumor had a near complete response to sirolimus that was durable for 18 months. Immunohistochemistry for phosphorylated S6, which has been reported to be associated with tumor sensitivity to mTORC1 inhibitors, was positive in this patient's tumor.

Object: Few reports describe the outcome and prognostic factors for children with gangliogliomas. The objective of this report was to describe the progression-free survival (PFS) for children with low-grade gangliogliomas and identify risk factors for tumor progression., Methods: A retrospective study was performed in children with low-grade gangliogliomas who were evaluated and treated in the neuro-oncology department between 1986 and 2006 to determine risk factors for subsequent tumor progression., Results: A total of 38 children with newly diagnosed gangliogliomas were included in this report. Thirty-four children were treated with surgery alone, 3 with subtotal resection and radiation therapy, and 1 with subtotal resection and chemotherapy. The follow-up ranged from 4 months to 15.8 years (mean 5.7+/-4.2 years [+/-SD]). Seven children have experienced tumor progression, and 1 child died after his tumor subsequently underwent malignant transformation. The 5-year PFS was calculated to be 81.2% using Kaplan-Meier survival analysis. Initial presentation with seizures (p=0.004), tumor location in the cerebral hemisphere (p=0.020), and complete tumor resection (p=0.035) were associated with prolonged PFS. Further analysis of the above significant variables by a Cox regression model identified initial presentation with seizures as being associated with prolonged PFS (p=0.028)., Conclusions: The PFS and overall survival of children with gangliogliomas are good. Tumors located in the cerebral hemispheres, the achievement of total resection, and seizures at presentation were associated with prolonged PFS. Cox regression analysis identified presenting symptoms including seizures as significant predictive factors of PFS. Prospective studies with larger numbers of children are needed to define the significant factors of tumor progression.

A 3-year old male presented with complaints of pruritus, abdominal pain for 3 weeks and jaundice. Stools were acholic. There was jaundice, liver palpable 3 cm below right costal margin, no ascites or palpable masses. Serology revealed albumin 2.9 g/dl; ammonia of 31 mmol/l; elevated conjugated bilirubin, GGT, ALT, AST and alkaline phosphatase; alpha fetoprotein 1.3 ngm/ml; BhCG 9.1 IU/; PT 12.3 secs, INR 0.9; negative hepatitis A,B,C serology. CT scan showed a non-calcified heterogeneously enhancing mass centered at the liver hilum. MRCP showed a large heterogeneously enhancing, partially solid mass in the region of the porta hepatic. Liver biopsy revealed patternless proliferation of polymorphic oval to spindled shaped neoplastic cells. There was bile ducts distortion. Immunohistochemistry revealed positivity for vimentin, desmin.These findings were diagnostic for biliary rhabdomyosarcoma.There was no evidence of metastasis. Chemotherapy was initiated. Repeat imaging 6 months after initiation of treatment showed improvement in the degree of intrahepatic ductal dilatation and decrease in tumor bulk size. Rhabdomyosarcoma is the most common malignant tumor of the biliary tree in childhood. It is difficult to diagnose and delayed diagnosis influences the prognosis.

Despite its use, there is little evidence to support volume infusion (VI) during neonatal cardiopulmonary resuscitation (CPR). This study compares 5% albumin (ALB), normal saline (NS), and no VI (SHAM) on development of pulmonary edema and restoration of mean arterial pressure (MAP) during resuscitation of asphyxiated piglets. Mechanically ventilated swine (n=37, age: 8 +/- 4 d, weight: 2.2 +/- 0.7 kg) were progressively asphyxiated until pH <7.0, Paco2 >100 mm Hg, heart rate (HR) <100 bpm, and MAP <20 mm Hg. After 5 min of ventilatory resuscitation, piglets were randomized blindly to ALB, NS, or SHAM infusion. Animals were recovered for 2 h before euthanasia and lung tissue sampled for wet-to-dry weight ratio (W/D) as a marker of pulmonary edema. SHAM MAP was similar to VI during resuscitation. At 2 h post-resuscitation, MAP of SHAM (48 +/- 13 mm Hg) and ALB (43 +/- 19 mm Hg) was higher than NS (29 +/- 10 mm Hg; p=0.003 and 0.023, respectively). After resuscitation, SHAM piglets had less pulmonary edema (W/D: 5.84 +/- 0.12 versus 5.98 +/- 0.19; p=0.03) and better dynamic compliance (Cd) compared with ALB or NS (Cd: 1.43 +/- 0.69 versus 0.97 +/- 0.37 mL/cm H2O, p=0.018). VI during resuscitation did not improve MAP, and acute recovery of MAP was poorer with NS compared with ALB. VI was associated with increased pulmonary edema. In the absence of hypovolemia, VI during neonatal resuscitation is not beneficial.

The current authors have previously identified BR22, a thyroid transcription factor (TTF)-1 associated protein 26 (TAP26), which interacts with TTF-1 to enhance human surfactant protein (SP)-B promoter activity in transfected 293 cells. However, the expression of TAP26 in the lung cells and its biological relevance to the SP-B production under physiological conditions were not examined. In this study, endogenous co-immunoprecipitation and in situ immunohistochemical staining techniques were employed to explore the presence of TAP26 and TTF-1 complex in the lung epithelial cells. The correlation of TAP26, TTF-1 and SP-B expression was inspected in H441 cells in the presence of dexamethasone, a known positive effector of the SP-B promoter. Monoclonal antibody (mAb) against TAP26 can co-immunoprecipitate both TAP26 and TTF-1 from H441 cells. Using this antibody in in situ staining of human lung sections, the data show that TAP26 is present in the lung alveolar epithelial cells. Reverse transcriptase-polymerase chain reaction and Western blot analyses of type-II cells as well as dexamethasone-treated H441 cells suggest that TAP26 expression is modulated coordinately with SP-B and TTF-1 in these cells. In summary, the current study demonstrates that thyroid transcription factor-1 associated protein 26 is an associated protein of thyroid transcription factor-1 in the lung alveolar epithelial cells where surfactant protein gene expressions take place in vivo.

Oligodendrogliomas (OGs) are rare in children and have not been well characterized from a molecular viewpoint. In adults, losses on chromosomes 1p and/or 19q are common in "oligodendroglial" neoplasms and are highly associated with chemosensitivity and greater length of survival, especially in the anaplastic category. We have analyzed the 1p/19q status of pediatric OGs and compared it with similar alterations in adult OGs. Paraffin sections from 26 pediatric OGs (21 WHO Grade II OGs: 2 anaplastic oligodendrogliomas [AOGs]: and 3 mixed oligo-astrocytomas [MOA]) were retrieved. Fluorescence in situ hybridization (FISH) was performed using probes spanning the 1p32 and 19q13 regions. In tumors from children 0 to 9 years of age (n = 15), none had any deletions on 1p or 19q, but 2 had polysomies for 1p and/or 19q. All are alive and 4 have had recurrences. In tumors from children > 9 years, losses were identified on chromosomes 1p (5/11; 45%) and/or 19q (3/11; 27%), but to a much lesser extent than that observed in adult OGs. Tumors from 6 older patients also had polysomies for 1p and/or 19q. Although the majority of the older children are alive, 4 had recurrences. Curiously, 2 of the older children with AOGs had combined losses and polysomies on 1p and 19q, but responded poorly to treatment and died within a year. We conclude that alterations on 1p or 19q are infrequent in pediatric compared to adult OGs and are virtually absent in OGs presenting in the first decade of life. Compared to adults therefore, different genetic pathways are likely involved in the pathogenesis of most pediatric OGs. Genomic screening on a larger series is clearly indicated to delineate the unique molecular characteristics of these rare pediatric tumors.

Pediatric and NF2-associated meningiomas are uncommon and poorly characterized in comparison to sporadic adult cases. In order to elucidate their molecular features, we analyzed MIB-1, progesterone receptor (PR), NF2, merlin, DAL-1, DAL-1 protein, and chromosomal arms 1p and 14q in 53 meningiomas from 40 pediatric/NF2 patients using immunohistochemistry and dual-color fluorescence in situ hybridization (FISH). Fourteen pediatric (42%) patients, including 5 previously undiagnosed patients, had NF2. The remaining 19 (58%) did not qualify. All 7 of the adult patients had NF2. Meningioma grading revealed 21 benign (40%), 26 atypical (49%), and 6 anaplastic (11%) examples. Other aggressive findings included high mitotic index (32%), high MIB-1 LI (37%), aggressive variant histology (e.g. papillary, clear cell) (25%), brain invasion (17%), recurrence (39%), and patient death (17%). FISH analysis demonstrated deletions of NF2 in 82%, DAL-1 in 82%, 1p in 60%, and 14q in 66%. NF2-associated meningiomas did not differ from sporadic pediatric tumors except for a higher frequency of merlin loss in the former (p = 0.020) and a higher frequency of brain invasion in the latter (p = 0.007). Thus, although pediatric and NF2-associated meningiomas share the common molecular alterations of their adult, sporadic counterparts, a higher fraction are genotypically and phenotypically aggressive. Given the high frequency of undiagnosed NF2 in the pediatric cases, a careful search for other features of this disease is warranted in any child presenting with a meningioma.

Fibrolamellar hepatocellular carcinoma (FHCC) is a unique histologic variant of HCC that occurs in a younger subset of patients than classical HCC, and is associated with a better prognosis. Wilms tumor (WT) is a malignant embryonal neoplasm of the kidney and is one of the most common solid tumors of childhood, occurring at an estimated frequency of 1 in 8000 to 10,000 births. Although second malignant neoplasms (SMNs) following therapy for WTs have been reported in the liver, the coexistence of HCC and WT is extremely rare. We present the first report of a synchronous anaplastic WT and FHCC in a previously healthy 4-year-old girl. Despite the presence of focal immunohistochemical positivity for p53 in the WT, molecular analysis failed to reveal a germline or somatic p53 mutation, and was inconclusive in establishing a clonal relation between the two tumors.

The purpose of our study was to confirm reports of an association of human papillomavirus (HPV) with neonatal giant cell hepatitis (GCH) and biliary atresia (BA), and to expand these studies to include cytomegalovirus (CMV), Epstein-Barr virus (EBV), human herpesvirus 6 (HHV6), and parvovirus B19 (PVB19). Frozen hepatic tissue was available for polymerase chain reaction (PCR) analysis in 19 cases of GCH or BA and 8 controls. Nested PCR to detect HPV types 6, 16, 18, and 33 was followed by 32P hybridization with generic probes. PCR followed by hybridization with a digoxigenin-labeled probe was used for all other viruses. HPV, EBV, and PVB19 were not detected in cases or controls. Two cases of GCH and 1 case of BA were PCR positive for CMV; controls were negative. HHV6 was detected in 6 cases: 2 GCH, 2 BA, and 2 controls. We conclude that HPV is not associated with GCH or BA. Detection of CMV in BA and GCH confirms other reports of this association. HHV6 requires further study to determine the significance of a positive PCR test in the livers of infants.

Juvenile neuronal ceroid lipofuscinosis (Batten disease) is a progressive neurologic disorder which results from mutations in the CLN3 gene, which normally produces a 48-kDa polypeptide of unknown function. To help characterize the CLN3 protein, we have studied its tissue distribution and subcellular localization in human tissues using three epitope-specific polyclonal antibodies to human CLN3 by immunoblot, immunocytochemical, and immunoelectron microscopic analysis. The most abundant CLN3 protein expression was in the gray matter of the brain, where it was localized to astrocytes, capillary endothelium, and neurons. CLN3 was also evident in peripheral nerve, in pancreatic islet cells, and within the seminiferous tubules in the testis. Staining was generally diffuse within the cytoplasm with some nuclear reactivity. Subcellular localization identified the CLN3 protein within the nucleus and along cell membranes. These results were contrasted with the cellular distribution of palmitoyl-protein thioesterase (PPT), the enzyme whose deficiency is responsible for infantile neuronal ceroid lipofuscinosis (CLN1). PPT was most abundant in brain and visceral macrophages where it displayed a coarse granular staining pattern typical of lysosomal distribution. Immunoelectron microscopy confirmed that PPT immunoreactivity was limited to lysosomes., (Copyright 1999 Academic Press.)

Parathyroid carcinoma is a rare cause of hypercalcemia in children but should be considered in a child presenting with an extremely elevated serum calcium level. The authors report the fifth case of parathyroid carcinoma in a child less than 16 years of age.

Nitric oxide (NO), generated by NO synthase (NOS), is an important mediator of physiological processes in the airway and lung parenchyma, and there is evidence that the pulmonary expression of the endothelial isoform of NOS (eNOS) is developmentally regulated. The purpose of the present study was to delineate the cellular distribution of expression of eNOS in the developing respiratory epithelium and to compare it with inducible (iNOS) and neuronal (nNOS) NOS. Immunohistochemistry was performed on fetal (125-135 days gestation, term 144 days), newborn (2-4 wk), and maternal sheep lungs. In fetal lung, eNOS expression was evident in bronchial and proximal bronchiolar epithelia but was absent in terminal and respiratory bronchioles and alveolar epithelium. Similar to eNOS, iNOS was detected in bronchial and proximal bronchiolar epithelia but not in alveolar epithelium. However, iNOS was also detected in terminal and respiratory bronchioles. nNOS was found in epithelium at all levels including the alveolar wall. iNOS and nNOS were also detected in airway and vascular smooth muscle. The cellular distribution of all three isoforms was similar in fetal, newborn, and adult lungs. Findings in the epithelium were confirmed by isoform-specific reverse transcription-polymerase chain reaction assays and NADPH diaphorase histochemistry. Thus the three NOS isoforms are commonly expressed in proximal lung epithelium and are differentially expressed in distal lung epithelium. All three isoforms may be important sources of epithelium-derived NO throughout lung development.

Adrenarche is the increased adrenal production of dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEAS) that occurs during the prepubertal period. To date, the exact mechanism initiating adrenarche is unknown, although many factors have been postulated. In the present study, we examined the hypothesis that alterations in intra-adrenal expression of 3beta-hydroxysteroid dehydrogenase (3betaHSD) or 21-hydroxylase (CYP21) within the inner reticularis zone leads to the increased production of 19-carbon (C19) steroids. After conversion of cholesterol to pregnenolone, 17alpha-hydroxylase/17,20-lyase (CYP17) can metabolize pregnenolone through to DHEA. The enzyme 3betaHSD competes for substrate with CYP17 and effectively removes steroid precursor from the pathway leading to DHEA. On the other hand, deficiency in CYP21 expression is known to cause excessive production of adrenal C19 steroids, suggesting that CYP21 could play a role in adrenarche. Thus, a decrease in 3betaHSD or CYP21 expression would allow substrate to flow toward the synthesis of DHEA. To determine whether adrenarche results from a decreased expression of 3betaHSD or CYP21 in the reticularis, immunohistochemical localization of 3betaHSD and CYP21 was performed, and staining intensities compared using adrenal glands from children ages 4 months to 4 yr (n = 12), ages 5-7 yr (n = 9), ages 8-13 yr (n = 9), and adults ages 25-56 yr (n = 8). There were no differences in the zonal expression of CYP21. No difference in 3betaHSD staining was observed between the glomerulosa and fasciculata from any age group. However, children age 8 yr and older show a significant decrease in 3betaHSD expression in reticularis as compared with the fasciculata. No significant difference was noted for 3betaHSD levels between the fasciculata and reticularis for children age 7 yr or younger. The level of 3betaHSD expression in the reticularis continued to decrease in the adult adrenals examined. These findings suggest that as children mature there is a decreased level of 3betaHSD in the adrenal reticularis that may contribute to the increased production of DHEA and DHEAS seen during adrenarche.

Langerhans' cell histiocytosis (LCH) is an abnormal accumulation of dendritic histiocytes of unknown pathogenesis. It has recently been shown to be a clonal process. Bcl-2 is a proto-oncogene whose protein product is known to inhibit apoptosis. The overexpression of bcl-2 has been demonstrated in a number of neoplasms, presumably prolonging the survival of the neoplastic cells. We examined the expression of bcl-2 in normal Langerhans' cells in the skin and in LCH by immunohistochemistry for protein and in situ hybridization for mRNA to see if it could be implicated in the pathogenesis of this disorder. Additionally, we performed Southern analysis to determine if genomic rearrangement of the bcl-2 gene occurs in cases of LCH. Bcl-2 was not detected in normal skin Langerhans' cells. Eleven of thirteen cases of LCH demonstrated bcl-2 protein expression in the cytoplasm of the Langerhans' cells by immunohistochemistry, while 12 of 13 cases had evidence of bcl-2 mRNA by in situ hybridization. Southern analysis revealed a germline configuration of the bcl-2 gene in the five cases studied. These findings suggest that bcl-2 expression is present and up-regulated in pathologic Langerhans' cells, however, this overexpression does not appear to be due to genomic rearrangement.

We hypothesized that the expression of surfactant protein A (SP-A) would be altered in developing lungs from rat fetuses with congenital diaphragmatic hernia (CDH) induced by maternal ingestion of 2,4-dichlorophenyl-p-nitrophenyl ether (Nitrofen) on Day 9 of gestation. We compared our findings in fetuses exposed to Nitrofen with a CDH with those in Nitrofen-exposed fetuses without a CDH, and control fetuses whose mothers received olive oil only, the vehicle for Nitrofen. In late gestation, immunocytochemistry using a polyclonal rabbit antihuman SP-A antibody revealed decreased amounts of this protein in lungs from fetuses with CDH. Using immunoblotting, the relative amount of SP-A on Day 21 of gestation was also decreased in lung tissue from fetuses with CDH compared with the other groups. Abnormalities of mRNA for SP-A were observed in both groups of Nitrofen-exposed fetuses compared with control rats. These findings suggest that there is decreased expression of SP-A in rat fetuses with CDH secondary to Nitrofen exposure.

Prostacyclin is a key mediator of pulmonary vascular and parenchymal function during late fetal and early postnatal life, and its synthesis in whole lung increases during that period. The rate-limiting enzyme in prostacyclin synthesis in the developing lung is cyclooxygenase (COX). We investigated the ontogeny and cellular localization of COX-1 (constitutive) and COX-2 (inducible) gene expression in lungs from late-gestation fetal lambs, 1-wk-old newborn lambs (NB1), and 1- to 4-mo-old newborn lambs (NB2). COX-1 mRNA abundance rose progressively from fetal to NB1 to NB2, increasing 12-fold overall. In parallel, immunoblot analysis revealed a progressive increase in COX-1 protein, rising fourfold from fetal lambs to NB2. COX-2 mRNA levels increased fivefold from fetal to NB1 but were similar in NB1 and NB2. However, COX-2 protein was not detectable by immunoblot analysis in any age group. Immunohistochemistry for COX-1 showed intense immunostaining in endothelial cells at all ages. COX-1 was also expressed in airway epithelium at all ages, with a greater number of epithelial cells staining positively in NB2 compared with fetal and NB1 groups. In addition, COX-1 was expressed in airway smooth muscle from NB1. COX-2 immunostaining was absent in all age groups. These findings indicate that there is differential expression of COX-1 and COX-2 in the developing lung and that the enzymes are expressed in a cell-specific manner. The developmental upregulation in COX-1 may optimize the capacity for prostaglandin-mediated vasodilation, bronchodilation, and surfactant synthesis in the newborn lung.

Studies of the regulation of surfactant lipoprotein metabolism and secretion and surfactant protein gene expression have been hampered by the lack of a cell culture system in which the phenotypic properties of type II cells are maintained. We have developed a primary culture system that facilitates the maintenance of a number of morphologic and biochemical properties of type II pneumonocytes for up to 2 wk. Cells were isolated by collagenase digestion of midgestation human fetal lung tissue that had been maintained in organ culture in the presence of dibutyryl cyclic AMP (Bt2cAMP) for 5 days. The isolated cells were enriched for epithelial components by treatment with DEAE-dextran, plated on an extracellular matrix (ECM) derived from Madin-Darby canine kidney (MDCK) cells, and incubated at an air/liquid interface in a minimal amount of culture medium containing Bt2cAMP. The cell cultures were comprised of islands of round epithelial-like cells containing numerous dense osmiophilic granules, surrounded by sparse spindle-shaped cells with the appearance of fibroblasts. Ultrastructural examination revealed that the osmiophilic granules had the appearance of lamellar bodies, the distinguishing feature of type II pneumonocytes. Additionally, the cultures maintained elevated levels of SP-A gene expression for up to 2 wk. The expression of mRNAs encoding SP-A, SP-B, and SP-C were regulated in the cultured cells by glucocorticoids and cyclic AMP in a manner similar to that observed in fetal lung tissue in organ culture. The differentiated phenotype was most apparent when the cells were cultured at an air/liquid interface. In order to utilize the cultured type II cells for study of the effects of overexpression of various proteins and for promoter analysis, it is of essence to transfect DNA constructs into these cells with high efficiency. Unfortunately, we found the cells to be refractory to efficient transfer of DNA using conventional methods (i.e., lipofection, electroporation, or calcium phosphate-mediated transfection). However, replication-defective recombinant human adenoviruses were found to provide a highly efficient means of introducing DNA into the type II pneumonocytes. Furthermore, we observed in type II cell-enriched cultures infected with recombinant adenoviruses containing the lacZ gene under control of a cytomegalovirus promoter, that beta-galactosidase was expressed uniformly in the islands of type II cells and surrounding fibroblasts. By contrast, in cultures infected with recombinant adenoviruses containing the human growth hormone (hGH) gene under control of the SP-A gene promoter and 5'-flanking region, hGH was expressed only in the type II cells. Thus, this culture system provides an excellent means for identifying genomic elements that mediate type II cell-specific gene expression.

Pulmonary surfactant is a developmentally and hormonally regulated lipoprotein synthesized exclusively in alveolar type II cells. Surfactant protein-A (SP-A) gene transcription in human fetal lung in culture is stimulated by glucocorticoids and cAMP; cAMP also enhances the rate of type II cell differentiation. The CCAAT/enhancer-binding protein (C/EBP) family of transcription factors serves an important role in the regulation of genes involved in energy metabolism, lipid biosynthesis, and cellular differentiation. The gene encoding C/EBPdelta, which is induced by glucocorticoids during the early phases of adipocyte differentiation, is expressed at relatively high levels in lung compared with other tissues. In the present study we have analyzed developmental changes in C/EBPdelta messenger RNA levels in fetal rabbit lung as well as changes in the levels of immunoreactive C/EBPdelta in human fetal lung during differentiation in organ culture and after treatment with cAMP and glucocorticoids. We observed that C/EBPdelta messenger RNA is detectable in fetal rabbit lung on day 19 of gestation and is increased approximately 3.7-fold to maximum levels on day 28 of gestation, the time when SP-A gene transcription increases to maximum levels. Immunohistochemical analysis of C/EBPdelta in midgestation human fetal lung before culture revealed trace nuclear staining in epithelial and occasional stromal cells. After 12 h of organ culture in serum-free medium, nuclear staining of C/EBPdelta was markedly increased in epithelial cells lining the prealveolar ducts of the human fetal lung tissue. By immunoblot analysis, it was found that C/EBPdelta levels were induced rapidly during organ culture in control medium and were increased further by treatment with dexamethasone and (Bt)2cAMP. C/EBPdelta levels were maximally induced during the first 24 h of culture and declined thereafter; after 72 h of incubation in control or cAMP-containing medium, C/EBPdelta was reduced markedly. By contrast, in fetal lung tissues incubated in medium containing dexamethasone or dexamethasone plus (Bt)2cAMP, the decline in C/EBPdelta was more modest, so that levels remained elevated throughout the 96-h culture period. Our findings that C/EBPdelta is localized primarily to alveolar epithelial cells, rapidly induced during differentiation of human fetal lung in culture, and increased by cAMP and glucocorticoids suggest a possible role in the regulation of type II cell differentiation and in the synthesis of surfactant phospholipids and proteins.

Purpose: The purpose of this study is to report a case of Epstein-Barr virus-related lymphoproliferative disorder (EBV-related LPD) in a child with leukemia and present a review of literature on the subject., Patients and Methods: A 6-year-old boy with acute lymphoblastic leukemia (ALL) undergoing maintenance chemotherapy presented with fever, abdominal pain, and vomiting. Imaging studies revealed multiple mass lesions in the liver, kidneys, and lungs. Liver biopsy was obtained. Immunocytochemistry for T and B lymphocytes and in situ hybridization for evidence of latent EBV infection was performed., Results: Hepatic portal tracts were infiltrated with lymphocytes, monocytes, eosinophils, and large atypical mononuclear cells. Both T and B lymphocytes were present, but the large atypical cells were of B origin and were positive for latent EBV infection. Chemotherapy was discontinued, and the patient was treated with intravenous gammaglobulin, interferon, and acyclovir. He had an excellent response and has been free of disease for 19 months., Conclusion: EBV-related LPD can complicate the course of patients with ALL in remission. The clinical findings and diagnosis in patients with ALL are similar to other immunocompromised patients. Withdrawal of chemotherapy and treatment with immune modulators should be strongly considered.

Nitric oxide (NO) is a pluripotent molecule that can be secreted by skeletal muscle through the activity of the neuronal constitutive isoform of NO synthase. To determine whether skeletal muscle and diaphragm might also express the macrophage-inducible form of NO synthase (iNOS) during provocative states, we examined tissue from mice at serial times after intravenous administration of Escherichia coli endotoxin. In these studies, iNOS mRNA was strongly expressed in the diaphragm and skeletal muscle of mice 4 h after intravenous endotoxin and was significantly diminished by 8 h after challenge. Induction of iNOS mRNA was followed by expression of iNOS immunoreactive protein on Western immunoblots. Increased iNOS activity was demonstrated by conversion of arginine to citrulline. Immunochemical analysis of diaphragmatic explants exposed to endotoxin in vitro revealed specific iNOS staining in myocytes, in addition to macrophages and endothelium. These results may be important in understanding the pathogenesis of respiratory pump failure during septic shock, as well as skeletal muscle injury during inflammation or metabolic stress.

The increased production of adrenal dehydroepiandrosterone (DHEA) and DHEA-sulfate (DHEAS) which occurs during the prepubertal period is known as adrenarche. One hypothesis for adrenarche is that alterations in intra-adrenal expression of steroidogenic enzymes within the inner reticularis zone leads to the increased production of 19-carbon steroids. We tested the hypothesis that at the time of adrenarche there is decreased expression of 3 beta HSD in the reticularis. Immunohistochemical localization of 3 beta HSD was performed and staining intensities compared between adrenal glands from children ages 4 months to 7 years (N = 11) and ages 8 to 11 years (N = 6). No difference was observed between the levels of staining in the glomerulosa and fasciculata from either age group. However, the reticularis from the older children exhibited diminished 3 beta HSD immunoreactivity. These findings suggest that as children mature there is a decreased level of 3 beta HSD in the adrenal reticularis which may contribute to the increased production of DHEA and DHEAS seen during adrenarche.

This report concerns the finding of a clinically benign 4-cm mass in the anterior thorax of a 12-year-old girl. The tumor was inseparable from the chest wall. A wide excision was performed. Microscopic examination proved it to be a rare but distinctive lesion recently entitled "calcifying fibrous pseudotumor" primarily involving the chest wall. Wide excision is thought necessary to preclude local recurrence.

To investigate how overexpression of MAD, an antagonist of MYC oncogenes influences the malignant phenotype of human cancer cells, an adenovirus vector system was used to transfer the human MAD gene (AdMAD) into human astrocytoma cells. Decreased growth potential of AdMAD-infected cells was evidenced by a decrease in [3H]thymidine incorporation, an increase in cell doubling time and alteration of cell-cycle distribution. Diminished malignant potential of AdMAD-infected cells was manifested by their loss of anchorage-independent growth in soft agar and by their inability, in general, to induce tumorigenesis in a xenograft animal model. These studies indicate that adenovirus constructs encoding MAD dramatically inhibit the proliferation and tumorigenicity of human astrocytoma cells and support the use of MAD for gene therapy of human tumours.

Gastrin-releasing peptide (GRP) is a developmentally regulated bioactive peptide believed to function as a pulmonary growth factor. It is produced by pulmonary neuroendocrine cells, found within the conducting and respiratory epithelium, as isolated cells and in clusters known as neuroepithelial bodies (NEBs). Deficient GRP expression has been reported in pulmonary hypoplasia (PH) associated with oligohydramnios and diaphragmatic hernia. To assess further the role of GRP in maldeveloped lung we reviewed the postmortem records and histologic lung sections, stained with H&E and anti-GRP antiserum, from 11 infants with anencephaly and 11 age-matched controls. Cells immunoreactive for GRP were quantified (isolated versus NEBs) in airways and airspaces per mm2 for a standard area. PH was present in five anencephalic infants. There was no difference in the total number of GRP-positive cells, number of NEBs, size of NEBs, or number of GRP-positive cells in airways or alveoli in either group regardless of lung development. A greater proportion of the GRP-positive cells was present in the airways in anencephalic infants with PH (58%) compared with anencephalic infants without PH (40%) (P = .018). There were no differences when comparing these groups with control infants and no differences in the density of airways in each of these groups. We conclude that deficient GRP expression is not a feature of lung hypoplasia in anencephalic infants. The altered distribution of GRP-positive cells in anencephalic infants with PH may be a reflection of the structural abnormalities or accompanying altered cellular maturity.

Limy bile syndrome (LBS) is a rare condition in which a radiopaque gallbladder and/or bile ducts are noted on plain roentgenograms. LBS is caused by calcium carbonate precipitation in the bile and is usually associated with distal biliary tract obstruction. The etiology of limy bile syndrome is unclear; however, it may be a long-term complication of total parenteral nutrition.

Improvements in prenatal imaging techniques now permit in utero treatment of potentially serious lesions. We describe three cases in which decompression of significant space-occupying thoracic lesions resulted in an excellent clinical outcome. The pregnancies were all carried to term after second or early third trimester intervention and resulted in infants with minimal respiratory distress. Cytologic and chemical analysis of the thoracic fluid aspirated in utero provided diagnostic and physiologic information.

Uteroglobin (UG) is a hormonally regulated secretory protein produced in the lung and urogenital system of rabbits. It is homologous to rat and human Clara cell 10 kD protein (CC10); however, there are significant differences in the tissue-specific expression between these species. Mouse CC10 (mCC10) protein has been less well characterized. In this study, we cloned and sequenced the cDNA encoding the mCC10 protein. The mouse cDNA showed 90, 52, and 51% amino acid homology to rat and human CC10 and rabbit UG cDNA, respectively. The cellular and tissue-specific expression of mCC10 was examined in adult and developing mice. Endogenous mCC10 expression was compared with transgenic mice expressing a fusion gene of the rabbit 3.3 kb UG promoter linked to human growth hormone (hGH) as an easily detectable marker. Northern blot analysis detected mCC10 mRNA only in the lung. hGH mRNA was detected in the lung in levels similar to the endogenous mCC10 transcripts. However, it was also present in trace quantities in the uterus and ovary of normal adult female mice and in the epididymus of adult male mice. hGH and mCC10 proteins were identified in the trachea and lung, where they were localized to Clara cells. Ultrastructurally, hGH was present in secretory granules in the Clara cell cytoplasm and appeared to be secreted into the airways. hGH was initially detectable in 16 day gestation developing mice; however, CC10 was not detectable until the eighteenth day of gestation. We have created an attractive model for comparing the cis-acting DNA elements governing the interspecies variation in tissue-specific expression of CC10.