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Brains are composed of anatomically and functionally distinct regions performing specialized tasks, but regions do not operate in isolation. Orchestration of complex behaviors requires communication between brain regions, but how neural dynamics are organized to facilitate reliable transmission is not well understood. Here we studied this process directly by generating neural activity that propagates between brain regions and drives behavior, assessing how neural populations in sensory cortex cooperate to transmit information. We achieved this by imaging two densely interconnected regions-the primary and secondary somatosensory cortex (S1 and S2)-in mice while performing two-photon photostimulation of S1 neurons and assigning behavioral salience to the photostimulation. We found that the probability of perception is determined not only by the strength of the photostimulation but also by the variability of S1 neural activity. Therefore, maximizing the signal-to-noise ratio of the stimulus representation in cortex relative to the noise or variability is critical to facilitate activity propagation and perception., (© 2023. The Author(s).)

For workplaces which cannot operate as telework or remotely, there is a critical need for routine occupational SARS-CoV-2 diagnostic testing. Although diagnostic tests including the CDC 2019-Novel Coronavirus (2019-nCoV) Real-Time RT-PCR Diagnostic Panel (CDC Diagnostic Panel) (EUA200001) were made available early in the pandemic, resource scarcity and high demand for reagents and equipment necessitated priority of symptomatic patients. There is a clearly defined need for flexible testing methodologies and strategies with rapid turnaround of results for (1) symptomatic, (2) asymptomatic with high-risk exposures and (3) asymptomatic populations without preexisting conditions for routine screening to address the needs of an on-site work force. We developed a distinct SARS-CoV-2 diagnostic assay based on the original CDC Diagnostic Panel (EUA200001), yet, with minimum overlap for currently employed reagents to eliminate direct competition for limited resources. As the pandemic progressed with testing loads increasing, we modified the assay to include 5-sample pooling and amplicon target multiplexing. Analytical sensitivity of the pooled and multiplexed assays was rigorously tested with contrived positive samples in realistic patient backgrounds. Assay performance was determined with clinical samples previously assessed with an FDA authorized assay. Throughout the pandemic we successfully tested symptomatic, known contact and travelers within our occupational population with a ~ 24-48-h turnaround time to limit the spread of COVID-19 in the workplace. Our singleplex assay had a detection limit of 31.25 copies per reaction. The three-color multiplexed assay maintained similar sensitivity to the singleplex assay, while tripling the throughput. The pooling assay further increased the throughput to five-fold the singleplex assay, albeit with a subtle loss of sensitivity. We subsequently developed a hybrid 'multiplex-pooled' strategy to testing to address the need for both rapid analysis of samples from personnel at high risk of COVID infection and routine screening. Herein, our SARS-CoV-2 assays specifically address the needs of occupational healthcare for both rapid analysis of personnel at high-risk of infection and routine screening that is essential for controlling COVID-19 disease transmission. In addition to SARS-CoV-2 and COVID-19, this work demonstrates successful flexible assays developments and deployments with implications for emerging highly transmissible diseases and future pandemics., (© 2022. The Author(s).)

Abstract: Pediatric cranioplasty is indicated to repair skull defects with a wide variety of etiologies. The choice of graft material used to fill the defect is of paramount importance to the long-term success of this procedure. A variety of synthetic products have been commercially developed to avoid donor site morbidity. Here, the authors present the case of a 13-year-old boy with cranial Langerhans cell histiocytosis who underwent cranioplasty with a novel, calcium phosphate-based bone graft substitute (Montage). The patient presented 2 years postoperatively with a foreign body giant cell reaction that required explantation of the graft. The authors discuss potential considerations in choosing the most appropriate graft, potential contributors to this late adverse outcome, and the need for further research into the use of novel allograft materials in pediatric cranioplasty., Competing Interests: The authors report no conflicts of interest., (Copyright © 2022 by Mutaz B. Habal, MD.)

Laboratory behavioural tasks are an essential research tool. As questions asked of behaviour and brain activity become more sophisticated, the ability to specify and run richly structured tasks becomes more important. An increasing focus on reproducibility also necessitates accurate communication of task logic to other researchers. To these ends, we developed pyControl, a system of open-source hardware and software for controlling behavioural experiments comprising a simple yet flexible Python-based syntax for specifying tasks as extended state machines, hardware modules for building behavioural setups, and a graphical user interface designed for efficiently running high-throughput experiments on many setups in parallel, all with extensive online documentation. These tools make it quicker, easier, and cheaper to implement rich behavioural tasks at scale. As important, pyControl facilitates communication and reproducibility of behavioural experiments through a highly readable task definition syntax and self-documenting features. Here, we outline the system's design and rationale, present validation experiments characterising system performance, and demonstrate example applications in freely moving and head-fixed mouse behaviour., Competing Interests: TA Consulting contract with Open Ephys Production Site, AL, JR, SK, JE, MP, CM, MK, DK, RC, MW No competing interests declared, (© 2022, Akam et al.)

Synchronization of precise spike times across multiple neurons carries information about sensory stimuli. Inhibitory interneurons are suggested to promote this synchronization, but it is unclear whether distinct interneuron subtypes provide different contributions. To test this, we examined single-unit recordings from barrel cortex in vivo and used optogenetics to determine the contribution of parvalbumin (PV)- and somatostatin (SST)-positive interneurons to the synchronization of spike times across cortical layers. We found that PV interneurons preferentially promote the synchronization of spike times when instantaneous firing rates are low (<12 Hz), whereas SST interneurons preferentially promote the synchronization of spike times when instantaneous firing rates are high (>12 Hz). Furthermore, using a computational model, we demonstrate that these effects can be explained by PV and SST interneurons having preferential contributions to feedforward and feedback inhibition, respectively. Our findings demonstrate that distinct subtypes of inhibitory interneurons have frequency-selective roles in the spatiotemporal synchronization of precise spike times., (Copyright © 2020 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).)

Several RT-PCR and genome sequencing strategies exist for the resolution of Foot-and-Mouth Disease virus (FMDV). While these approaches are relatively straightforward, they can be vulnerable to failure due to the unpredictable nature of FMDV genome sequence variations. Sequence independent single primer amplification (SISPA) followed by genotyping microarray offers an attractive unbiased approach to FMDV characterization. Here we describe a custom FMDV microarray and a companion feature and template-assisted assembler software (FAT-assembler) capable of resolving virus genome sequence using a moderate number of conserved microarray features. The results demonstrate that this approach may be used to rapidly characterize naturally occurring FMDV as well as an engineered chimeric strain of FMDV. The FAT-assembler, while applied to resolving FMDV genomes, represents a new bioinformatics approach that should be broadly applicable to interpreting microarray genotyping data for other viruses or target organisms., Competing Interests: The authors declare no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Foot-and-mouth disease (FMD) is a highly infectious viral disease of cloven-hoofed animals with debilitating and devastating consequences for livestock industries throughout the world. Key antigenic determinants of the causative agent, FMD virus (FMDV), reside within the surface-exposed proteins of the viral capsid. Therefore, characterization of the sequence that encodes the capsid (P1) is important for tracking the emergence or spread of FMD and for selection and development of new vaccines. Reliable methods to generate sequence for this region are challenging due to the high inter-serotypic variability between different strains of FMDV. This study describes the development and optimization of a novel, robust and universal RT-PCR method that may be used to amplify and sequence a 3kilobase (kb) fragment encompassing the leader proteinase (L) and capsid-coding portions (P1) of the FMDV genome. This new RT-PCR method was evaluated in two laboratories using RNA extracted from 134 clinical samples collected from different countries and representing a range of topotypes and lineages within each of the seven FMDV serotypes. Sequence analysis assisted in the reiterative design of primers that are suitable for routine sequencing of these RT-PCR fragments. Using this method, sequence analysis was undertaken for 49 FMD viruses collected from outbreaks in the field. This approach provides a robust tool that can be used for rapid antigenic characterization of FMDV and phylogenetic analyses and has utility for inclusion in laboratory response programs as an aid to vaccine matching or selection in the event of FMD outbreaks., (Published by Elsevier B.V.)

Sporadic fatal outbreaks of disease in humans and non-human primates caused by Ebola or Marburg viruses have driven research into the characterization of these viruses with the hopes of identifying host tropisms and potential reservoirs. Such an understanding of the relatedness of newly discovered filoviruses may help to predict risk factors for outbreaks of hemorrhagic disease in humans and/or non-human primates. Recent discoveries such as three distinct genotypes of Reston ebolavirus, unexpectedly discovered in domestic swine in the Philippines; as well as a new species, Bundibugyo ebolavirus; the recent discovery of Lloviu virus as a potential new genus, Cuevavirus, within Filoviridae; and germline integrations of filovirus-like sequences in some animal species bring new insights into the relatedness of filoviruses, their prevalence and potential for transmission to humans. These new findings reveal that filoviruses are more diverse and may have had a greater influence on the evolution of animals than previously thought. Herein we review these findings with regard to the implications for understanding the host range, prevalence and transmission of Filoviridae., (Published by Elsevier B.V.)

Purpose: Children with pure fetal histology (PFH) hepatoblastoma treated with complete surgical resection and minimal adjuvant therapy have been shown to have excellent outcomes when compared with other patients with hepatoblastoma. We prospectively studied the safety and efficacy of reducing therapy in all children with stage I PFH enrolled onto two consecutive studies., Patients and Methods: From August 1989 to December 1992, 9 children with stage I PFH were treated on the Intergroup Hepatoblastoma study INT-0098 and were nonrandomly assigned to receive chemotherapy after surgical resection with single-agent bolus doxorubicin for 3 consecutive days. From March 1999 to November 2006, 16 children with stage I PFH enrolled onto Children's Oncology Group Study P9645 were treated with observation after resection. Central confirmation of the histologic diagnosis by a study group pathologist was mandated. The extent of liver disease was assigned retrospectively according to the pretreatment extent of disease (PRETEXT) system and is designated "retro-PRETEXT" to clarify the retrospective group assignment., Results: Five-year event-free and overall survival for the 9 patients treated on INT-0098 were 100%. All 16 patients enrolled onto the P9645 study were alive and free of disease at the time of last contact, with a median follow-up of 4.9 years. Retro-PRETEXT for the 21 patients with available data revealed seven patients with stage I disease, 10 patients with stage II disease, and four patients with stage III disease., Conclusion: Children with completely resected PFH hepatoblastoma can achieve long-term survival without additional chemotherapy. When feasible, surgical resection of hepatoblastoma at diagnosis, without chemotherapy, can identify children for whom no additional therapy is necessary.

The historical chronologies for dynastic Egypt are based on reign lengths inferred from written and archaeological evidence. These floating chronologies are linked to the absolute calendar by a few ancient astronomical observations, which remain a source of debate. We used 211 radiocarbon measurements made on samples from short-lived plants, together with a Bayesian model incorporating historical information on reign lengths, to produce a chronology for dynastic Egypt. A small offset (19 radiocarbon years older) in radiocarbon levels in the Nile Valley is probably a growing-season effect. Our radiocarbon data indicate that the New Kingdom started between 1570 and 1544 B.C.E., and the reign of Djoser in the Old Kingdom started between 2691 and 2625 B.C.E.; both cases are earlier than some previous historical estimates.

Since the discovery of the Marburg and Ebola species of filovirus, seemingly random, sporadic fatal outbreaks of disease in humans and nonhuman primates have given impetus to identification of host tropisms and potential reservoirs. Domestic swine in the Philippines, experiencing unusually severe outbreaks of porcine reproductive and respiratory disease syndrome, have now been discovered to host Reston ebolavirus (REBOV). Although REBOV is the only member of Filoviridae that has not been associated with disease in humans, its emergence in the human food chain is of concern. REBOV isolates were found to be more divergent from each other than from the original virus isolated in 1989, indicating polyphyletic origins and that REBOV has been circulating since, and possibly before, the initial discovery of REBOV in monkeys.

Male animals of many species deploy conditional reproductive strategies that contain distinct alternative phenotypes. Such facultatively expressed male tactics are assumed to be due to a single developmental threshold mechanism switching between the expression of two alternative phenotypes. However, we discovered a clade of dung beetles that commonly expresses two threshold mechanisms, resulting in three alternative phenotypes (male trimorphism). Once recognized, we found trimorphism in other beetle families that involves different types of male weapons. Evidence that insects assumed to be dimorphic can express three facultative male forms suggests that we need to adjust how we think about animal mating systems and the evolution of conditional strategies.

Second malignant neoplasms (SMNs) are being increasingly recognized. This report describes a case of a 7-year-old girl with a history of acute lymphoblastic leukemia (ALL) who presented with a mass in her humerus that was diagnosed as Ewing sarcoma. Second malignant neoplasms are relatively rare in survivors of ALL treated without radiation. Even more unusual is the development of Ewing sarcoma as the SMN.

Blastic natural killer (NK) cell lymphoma is very rare but has been recently classified as a distinct entity in WHO classification. However, the classification remains controversial, and the clinicopathologic spectrum is not completely understood. We report a unique case of cutaneous CD4(+) CD56(+) malignancy with a typical clinical presentation and immunophenotype of blastic NK-cell lymphoma in a 15-year-old Guamanian girl. The skin was the only site involved by the lymphoma. Molecular study showed clonal T-cell receptor gamma gene rearrangement. The patient has been disease-free till now (more than 12 months following bone marrow transplant). This case may represent a tumor at an early stage of a common developmental pathway for T-cells and NK-cells., (Copyright 2004 Wiley-Liss, Inc.)

Three iron complexes of a pentadentate ligand N,N-bis(2-pyridylmethyl)amine-N-ethyl-2-pyridine-2-carboxamide (PaPy(3)H, H is the dissociable amide proton) have been synthesized. All three species, namely, two nitrosyls [(PaPy(3))Fe(NO)](ClO(4))(2) (2) and [(PaPy(3))Fe(NO)](ClO(4)) (3) and one nitro complex [(PaPy(3))Fe(NO(2))](ClO(4)) (4), have been structurally characterized. These complexes provide the opportunity to compare the structural and spectral properties of a set of isostructural [Fe-NO](6,7) complexes (2 and 3, respectively) and an analogous genuine Fe(III) complex with an "innocent" sixth ligand ([(PaPy(3))Fe(NO(2))](ClO(4)), 4). The most striking difference in the structural features of 2 and 3 is the Fe-N-O angle (Fe-N-O = 173.1(2) degrees in the case of 2 and 141.29(15) degrees in the case of 3). The clean (1)H NMR spectrum of 2 in CD(3)CN reveals its S = 0 ground state and confirms its [Fe-NO](6) configuration. The binding of NO at the non-heme iron center in 2 is completely reversible and the bound NO is photolabile. Mössbauer data, electron paramagnetic resonance signal at g approximately 2.00, and variable temperature magnetic susceptibility measurements indicate the S = (1)/(2) spin state of the [Fe-NO](7) complex 3. Analysis of the spectroscopic data suggests Fe(II)-NO(+) and Fe(II)-NO(*) formulations for 2 and 3, respectively. The bound NO in 3 does not show any photolability. However, in MeCN solution, it reacts rapidly with dioxygen to afford the nitro complex 4, which has also been synthesized independently from [(PaPy(3))Fe(MeCN)](2+) and NO(2)(-). Nucleophilic attack of hydroxide ion to the N atom of the NO ligand in 2 in MeCN in the dark gives rise to 4 in high yield.

A wide array of diagnostic tests are available to evaluate molecular abnormalities in pediatric cancer. Classic cytogenetics, FISH, flow cytometry, PCR, and Southern blot analysis are in widespread use throughout pediatric hospitals. Examples of the application of these methods in pediatric cancer diagnosis are reviewed. Newer methods such as CGH, SKY, gene expression microarrays and proteomic methods are under active investigation andwill almost certainly lead to significant advances in our ability to diagnose and treat pediatric cancer.

Background: Comparison of outcomes in different clinicopathologic studies of hepatoblastoma requires reproducible histologic classification. This review examines the diagnostic criteria employed by different pathologists for the classification of subtypes of hepatoblastoma and identifies specific problem areas., Procedure: A selected review of published literature is provided., Results: Published studies demonstrate that uniform criteria have not been applied in the classification of hepatoblastoma. These discrepancies hinder attempts to compare outcome data from different studies. Sampling error and potential treatment effects further complicate analysis of the published literature on the relationship between morphologic classification and outcome., Conclusions: Standardized criteria are essential to allow reproducible histologic classification of hepatoblastoma. There is significant variation in diagnostic criteria used to define the major subtypes of hepatoblastoma in published studies. Additional potential problems are identified in sampling methods and treatment effects., (Copyright 2002 Wiley-Liss, Inc.)

The Fe(III) and Co(III) complexes of the ligand N-(2-picolyl)picolinamide (pmpH; H represents the dissociable amide hydrogen), namely, [Fe(pmp)(2)]BF(4) (1) and [Co(pmp)(2)]ClO(4) (2), have been synthesized and structurally characterized. The [bond]CH(2)[bond] moiety of pmp(-) in [M(pmp)(2)](+) (M = Fe, Co) is very reactive and is readily converted to carbonyl (C[double bond]O) group upon exposure to dioxygen. Such conversion results in [M(bpca)(2)]ClO(4) complexes (M = Fe (3), Co (5); bpcaH = bis(2-pyridylcarbonyl)amine) which have been characterized by spectroscopy and X-ray diffraction. The structure of 5 is reported here for the first time. The reactivity of the [bond]CH(2)[bond] moiety of pmp(-) has so far precluded the isolation of 1 although other metal complexes of pmp(-) have been reported years ago. The CH(2) --> C[double bond]O transformation arises from the tendency of the coordinated pmp(-) ligand to achieve further conjugation in the ligand framework and provides a better way to synthesize the metal complexes of bpcaH ligand. Reaction of 3 with NaH affords Fe(II) complex [Fe(bpca)(2)] (4) without any reduction of the ligand frame.

Cystic fibrosis pulmonary disease is assessed by pulmonary function tests, arterial blood gases, and chest X-rays, but the correlation with lung pathology is unknown. We reviewed the clinical findings and lung pathology of 21 cystic fibrosis patients who had lung transplant. Pulmonary function tests, Brasfield scores, arterial blood gases, and age were correlated with lung pathology. All patients had severe Brasfield scores (9.0 +/- 3.2), airways obstruction (FEV1 25.6 +/- 5.6% predicted, FEF(25-75%) 11.0 +/- 4.5% predicted), and hyperinflation (residual volume [RV] 341.8 +/- 75.8% predicted). All patients were hypoxemic (PO2 64.2 +/- 8.2 mm Hg), and 5 of 21 (24%) were hypercapneic (PCO2 > 50 mm Hg). Pulmonary function tests and Brasfield scores were within a narrow range, and did not allow correlation with lung pathology. Small airway density (airways < 2 mm/cm2) decreased with increasing age. There were no differences in small airways inflammation and fibrous narrowing between the hypercapneic and nonhypercapneic patients, but the percent of smallest airways (airways < 0.35 mm) was significantly lower in the hypercapneic group. We conclude that there is significant correlation between airway pathology and increased age and CO2 retention. We speculate that decreased small airway density in older patients and the decreased proportion of smallest airways in hypercapneic patients is caused by increased dilatation of small airways.

Reaction of Cu(ClO(4))(2) x 6H(2)O with a racemic mixture of the novel chiral ligand N-(1,2-bis(2-pyridyl)ethyl)pyridine-2-carboxamide (PEAH) affords only the homochiral dimeric copper(II) complexes [Cu(2)((R)()PEA)(2)](ClO(4))(2) and [Cu(2)((S)()PEA)(2)](ClO(4))(2) in a 1:1 ratio. The phenomenon of molecular self-recognition is also observed when a racemic mixture of the monomeric copper(II) complex [Cu((R(S))()PEA)(Cl)(H(2)O)] is converted into the homochiral dimeric species [Cu(2)((R(S))()PEA)(2)](ClO(4))(2) via reaction with Ag(+) ion. This is the first report of direct conversion of a racemic mixture of a chiral monomeric copper(II) complex to a mixture of the homochiral dimers.

A new pentacoordinate ligand based on TPA (tris-(2-pyridylmethyl)amine), namely, N,N-bis(2-pyridylmethyl)amine-N-ethyl-2-pyridine-2-carboxamide (PaPy(3)H), has been synthesized. The iron(III) complexes of this ligand, namely, [Fe(PaPy(3))(CH(3)CN)](ClO(4))(2) (1), [Fe(PaPy(3))(Cl)]ClO(4) (2), [Fe(PaPy(3))(CN)]ClO(4) (3), and [Fe(PaPy(3))(N(3))]ClO(4) (4), have been isolated and complexes 1-3 have been structurally characterized. These complexes are the first examples of monomeric iron(III) complexes with one carboxamido nitrogen in the first coordination sphere. All four complexes are low spin and exhibit rhombic EPR signals around g = 2. The solvent bound species [Fe(PaPy(3))(CH(3)CN)](ClO(4))(2) reacts with H(2)O(2) in acetonitrile at low temperature to afford [Fe(PaPy(3))(OOH)](+) (g = 2.24, 2.14, 1.96). When cyclohexene is allowed to react with 1/H(2)O(2) at room temperature, a significant amount of cyclohexene oxide is produced along with the allylic oxidation products. Analysis of the oxidation products indicates that the allylic oxidation products arise from a radical-driven autoxidation process while the epoxidation is carried out by a distinctly different oxidant. No epoxidation of cyclohexene is observed with 1/TBHP.

Purpose: To report a rare case of rhabdomyomatous mesenchymal hamartoma and to compare its features with those cases previously reported., Design: Interventional case report and literature review., Intervention: Complete ophthalmologic and systemic examinations followed by excisional biopsy and histopathologic examination., Main Outcome Measures: Clinical examination features and histopathologic findings., Results: A 6-month-old Latino male presented with a congenital, elevated, smooth, flesh-colored right lower eyelid lesion. An ipsilateral right limbal dermoid and an upper eyelid coloboma were also present. Excisional biopsy of the eyelid lesion revealed randomly oriented mature striated muscle tissue with associated adipose tissue, blood vessels, pilosebaceous units, and peripheral nerves, findings consistent with rhabdomyomatous mesenchymal hamartoma. Of the 24 reported cases (including the current case), eight had associated congenital anomalies., Conclusions: Although rhabdomyomatous mesenchymal hamartomas are rare and benign, they may be associated with other congenital anomalies and anomaly syndromes. As a result, we recommend systemic evaluation of patients diagnosed with this entity.

The novel tripodal ligand N-(bis(2-pyridyl)methyl)-2-pyridinecarboxamide (Py3AH) affords monomeric and dimeric copper(II) complexes with coordinated carboxamido nitrogens. Although many chloro-bridged dimeric copper(II) complexes are known, [Cu(Py3A)(Cl)] (1) remains monomeric and planar with a pendant pyridine and does not form either a chloro-bridged dimer or the ligand-shared dimeric complex [Cu(Py3A)(Cl)]2 (4) in solvents such as CH3CN. When 1 is dissolved in alcohols, square pyramidal alcohol adducts [Cu(Py3A)(Cl)(CH3OH)] (2) and [Cu(Py3A)(Cl)(C2H5OH)] (3) are readily formed. In 2 and 3, the ROH molecules are bound at axial site of copper(II) and the weak axial binding of the ROH molecule is strengthened by intramolecular hydrogen bonding between ROH and the pendant pyridine nitrogen. Two ligand-shared dimeric species [Cu(Py3A)(Cl)]2 (4) and [Cu(Py3A)]2(ClO4)2 (5) have also been synthesized in which the pendant pyridine of one [Cu(Py3A)] unit completes the coordination sphere of the other [Cu(Py3A)] neighbor. These ligand-shared dimers are obtained in aqueous solutions or in complete absence of chloride in the reaction mixtures.

Background: Long-term survival in lung transplant is limited by bronchiolitis obliterans (BOS). We compared outcomes in pediatric living donor bilateral lobar (LL) vs cadaveric lung transplant (CL)., Methods: Children were studied who had LL or CL with at least 1 year follow-up. Data collected included acute rejection episodes, pulmonary function tests (PFT), BOS, and survival. Mean age was 13.36+/-3.16 years in LL and 12.00+/-4.19 years in CL patients (p = 0.37, ns)., Results: There was no difference in rejection (p = 0.41, ns). CL had rejection earlier (2.48+/-3.84 months) than LL (13.60+/-10.74 months; p = 0.02). There was no difference in 12 month PFT. But at 24 months, LL had greater forced expiratory volume in 1 second (FEV1) (p = 0.001) and FEF25-71% (p = 0.01) than CL. BOS was found in 0/14 LL vs 9/11 (82%) CL after 1 year (p = 0.04). After 2 years, 0/8 LL and 6/7 (86%) CL had BOS (p < 0.05). LL had 85% survival vs 79% for CL at 12 months. At 24 months, LL survival was 77% vs 67% for CL., Conclusions: Pediatric LL had less BOS and better pulmonary function than CL. As BOS is a determinant of long-term outcome, we believe LL is the preferred lung transplant method for children.

The authors describe common embryological pathways responsible for coexistent neurenteric and enterogenous cysts in a patient with spinal dysraphism.

Prompt and accurate diagnosis of small round cell tumors warrants ancillary studies. Recently, two-color fluorescence in-situ hybridization (FISH) using probes for specific gene rearrangements has gained wide acceptance. EWS gene rearrangements, present in essentially 100% of Ewing's Sarcoma/peripheral primitive neuroectodermal tumor, were evaluated by FISH on frozen sections (FS) of tumor biopsies from 10 patients, plus a negative control, and in seven other malignant neoplasms of childhood. 4mu FS were hybridized overnight, using a single EWS gene-specific probe spanning the EWS breakpoint. We identified EWS rearrangements in 8 of 10 cases (80%) of Ewing's Sarcoma/pPNET. There are no known false positives in diploid or near-diploid tumors, or in any of the non-EWS tumors tested; the uncommon false negative can be confirmed by RT-PCR. Hyperdiploid cases with multiple copies of chromosome 22 may be better evaluated by two-color FISH. This is the first use on FS biopsy material of a single probe for EWS, capable of detecting all known EWS rearrangements, in ES and other tumors. Utilization of this ancillary technique on FS for ES/pPNET and other tumors with distinctive chromosomal translocation is highly specific, reliable, expeditious (24-36 hours) and cost-effective.

An 11-month-old girl had massive rectal bleeding. A midabdominal mass was palpated. Ultrasound scan showed a large cystic mass with diffusely echogenic contents; Tc-99M radionuclide scan confirmed a duplication. Exploratory surgery and pathology examination showed a gastric duplication with formation of a fistula into the transverse colon with a colonic ulcer and hemorrhage. This combination of findings is presented as a rare cause of lower gastrointestinal hemorrhage in infancy.

A 12-year-old girl with a mixed malignant germ cell tumor of the ovary, treated by surgery and chemotherapy, developed systemic mast cell disease (SMCD) approximately 3 months after chemotherapy. Hematologic malignancies have previously been noted in patients with mediastinal germ cell tumors but this is the first report of a primary ovarian germ cell neoplasm associated with SMCD.

Objective: To establish the diagnostic usefulness of submucosal hypertrophic nerve trunk morphology in Hirschsprung's disease as a quantifiable parameter supportive of aganglionosis on hematoxylin-eosin-stained sections., Design: We retrospectively evaluated size and density of submucosal nerves on hematoxylin-eosin-stained sections and S100 protein-stained sections of resected segments from 13 patients with Hirschsprung's disease, and in sections of 20 aganglionic and 50 ganglionic rectal suction biopsies., Setting: All patients were seen at Childrens Hospital Los Angeles (Calif), a tertiary-care pediatric center; the age of patients at diagnosis or resection ranged between 2 days and 3 years., Results: Aganglionic segments contain many distinct nerve trunks greater than 40 microm in diameter. Ganglionic segments/biopsies showed no nerve trunk larger than this threshold value (P approximately .0000). Nerve trunks of such caliber are rarely encountered in pathologic transition zones and sites of colostomy., Conclusions: Submucosal nerve trunks that are 40 microm or greater in diameter strongly correlate with abnormal innervation/aganglionosis. Use of this objective parameter in evaluating suction biopsies should be helpful in the morphologic diagnosis of Hirschsprung's disease in infancy and early childhood.

Living donor (LD) lobar lung transplantation is now an accepted alternative to cadaveric lung transplantation in selected patients with end-stage lung disease. This study reviews the Childrens Hospital Los Angeles LD experience of 17 patients (mean 13.2 +/- 2.7 yrs; range 9.3-18.5 yrs). 12 LD patients had end-stage cystic fibrosis, 4 had primary pulmonary hypertension, and 1 child had bronchiolitis obliterans. LD candidates must meet the same criteria as for cadaveric lung transplant candidates. Donor candidates are rigorously screened (physically and psychologically) prior to acceptance for lobectomy. LD patients receive the same triple immunosuppression regimen as our cadaveric recipients (prednisone, cyclosporine/FK506, and azathioprine/mycophenolate). Comparison of rejection episodes, incidence of bronchiolitis obliterans, pulmonary function tests, exercise stress tests, and cardiac catheterization data was made between LD and cadaveric lung transplantation (CL) pediatric recipients. Donor outcomes were also reviewed. In our pediatric program, the 1-year survival rate for LD recipients is currently 81%, which compares favorably with the ISHLT average of 70% for pediatric transplant patients. The incidence of rejection is about the same for LD and CL recipients, but the episodes are less severe for pediatric LD patients. There have been no histological cases of bronchiolitis obliterans syndrome in our LD recipients. Although there have been questions as to whether transplanted lobes can supply comparable pulmonary reserve to whole cadaveric lungs, the lung volumes (TLC and VC), expiratory flow rates, maximal exercise stress tests, and pulmonary artery pressures (no evidence of pulmonary hypertension) in LD patients are not significantly different to CL recipients in our institution. Besides pain from the thoracotomy, the donors have a decrease of 16% (right lower lobe donor) and 18% (left lower lobe donor) in their vital capacity. Otherwise, there have been no major complications to the donors and most have resumed their usual activities. Based on outcomes, pulmonary function tests, exercise stress tests, and hemodynamic studies as well as low donor morbidity, living donor double lobar lung transplantation is a viable alternative to cadaveric lung transplantation in selected pediatric patients with end-stage lung disease.

In this study, we compare the morphological and genetic characteristics of 38 post-Chernobyl thyroid papillary carcinomas from Belarussian children 5-18 years old with those of 23 sporadic papillary carcinomas from the same age children without history of radiation exposure from Los Angeles and Cincinnati. Among radiation-induced tumors, solid variant of papillary carcinoma was found in 37%, follicular in 29%, typical papillary in 18%, and mixed and diffuse sclerosing variants in 8% each. In the sporadic group, a typical papillary pattern was prevalent in 70%, follicular in 17%, diffuse sclerosing variant in 9%, and solid in 4%. In both groups, the prevalence of ret rearrangements was high, but the frequency of specific types of rearrangement was significantly different. Among radiation-induced tumors, ret/PTC3 was found in 58%, ret/PTC1 in 16%, and ret/PTC2 in 3%, whereas among sporadic tumors, ret/PTC1 was found in 47% (P < 0.05), and ret/PTC3 was found in 18% (P = 0.01). The morphological variants of papillary carcinoma showed different prevalence of the specific types of ret rearrangement. Seventy-nine % of solid variant tumors had ret/PTC3, whereas only 7% had ret/PTC1 (P = 0.0007). Among typical papillary tumors, ret/PTC1 was found in 38%, ret/PTC3 in 19%, and ret/PTC2 in 5%. Thus, ret rearrangements are highly prevalent in pediatric papillary carcinomas from children exposed to radiation and in those occurring sporadically. However, the types of ret/PTC vary between these two populations, with ret/PTC3 present more commonly in post-Chernobyl tumors. Furthermore, solid variants have a high prevalence of ret/PTC3, whereas typical papillary carcinomas do not, suggesting that the different types of ret rearrangement confer neoplastic thyroid cells with distinct phenotypic properties.

We describe a case of malignant lymphoma mimicking the rheumatic presentation of sarcoidosis in an adolescent with a 3-year history of febrile illness. Final diagnosis was established by tissue biopsy after multiple studies failed to provide histological evidence of granulomas consistent with sarcoidosis. We discuss the limited diagnostic specificity of serum angiotensin converting enzyme in sarcoidosis and emphasize the need for aggressive diagnostic evaluation of a patient whose clinical presentation is not fully explained by a known rheumatologic illness.

The peripheral primitive neuroectodermal tumors (pPNETs) of childhood, including Ewing's sarcoma, peripheral neuroepithelioma, and Askin's tumor, often present significant diagnostic challenges for the anatomic pathologist. One consistent feature of these tumors is the presence of the t(11;22)(q24;q12) in tumor cells, and this translocation has been useful as a marker for this group of tumors. The recent cloning of the t(11;22) breakpoint has revealed the fusion of the human FLI-1 gene on chromosome 11q24 with a gene of unknown function called EWS on 22q12, and fusion transcripts have been detected. These findings have raised the possibility of using molecular genetic analysis as a tool to diagnose pPNETs. To this end, we have tested pPNETs for the presence of EWS/FLI-1 fusion transcripts by reverse transcriptase-polymerase chain reaction (RT-PCR) using EWS and FLI-1 specific primers. Eight (80%) of 10 pPNET cell lines were positive for amplified products using this technique. These results were confirmed by Southern analysis, which revealed rearrangements of EWS using genomic EWS probes in all eight positive cell lines. We then tested 20 primary pPNET tumors, and identified fusion transcripts by RT-PCR in 18 (90%) of these cases. Cloning and sequencing of PCR products confirmed the presence of EWS and FLI-1 sequences in these products. Furthermore, fusion transcripts were not detected by this technique in a series of non-pPNET pediatric solid tumors. Detection of EWS/FLI-1 fusion transcripts by RT-PCR therefore provides a novel adjunctive tool in the diagnosis of pPNETs.

The prevalence of immunity to Streptococcus pneumoniae in the adult population of the United States is unknown. In the study described herein, military recruits had anticapsular IgG antibody to only 15% of common pneumococcal serotypes, whereas working men and elderly men had IgG antibody to 33% and 34% of the common serotypes, respectively (P < .001). Among eight elderly subjects, the prevalence of IgG antibody to capsular polysaccharides increased from 30% to 78% after pneumococcal vaccination; 6 years thereafter, the rate of positive reactions had declined to 58% and IgG levels had declined substantially. With revaccination, IgG levels returned to within (+/-) 40% of the original postvaccination levels. IgM and IgG antibody appeared or began to increase in titer 6 days after vaccination; the rate and degree of response were the same after the first and second exposures. Since most individuals rapidly develop IgG antibody after colonization by S. pneumoniae and since IgG confers immunity, these data suggest that pneumonia is infrequent among healthy adults not because preexisting immunity is widespread but because--with colonization--an immune response develops rapidly, preceding specific events that might lead to infection. Our findings support recommended vaccination procedures and suggest that wider application in subsets of healthy younger adults should be considered.

Short repetition time magnetic resonance images of the pelvis in 70 subjects (aged 1 day to 24 years) without history of bone marrow disease were retrospectively analyzed for the distribution and appearance of red and yellow marrow. The signal intensity and degree of mottling of marrow in six anatomic regions of the pelvis were observed and were assigned a grade. Anatomic correlation was provided with gross and microscopic examination of bone marrow biopsy specimens taken from selected pelvic sites in cadavers of children. Marrow signal intensity increased in all pelvic regions except the acetabulum from birth to age 24 years. Marrow heterogeneity was most prominent in the acetabulum at all ages. Patterns of bone marrow signal intensity and heterogeneity are recognized for four age groups: the infant, child, adolescent, and young adult. Regional and age-related differences in the signal intensity of pelvic marrow correlate with the percentage of fat seen microscopically in marrow.

Cell-to-cell fusion plays an important role in the pathogenesis of human immunodeficiency virus type 1 (HIV-1) infections. An assay to measure the antifusion activity of serum has been developed by using the fusion event that occurs between H9 cells chronically infected with HIV-1 (H9IIIB) and fusion-susceptible MT-2 cells. The endpoint is determined by measuring neutral red uptake in cells after syncytium formation is allowed to occur in the presence of various serum dilutions. The assessment of antifusion activity in serum by neutral red uptake has been shown to correlate with syncytium reduction as determined by direct counting. The optimal number and ratio of cells in the suspension for efficiency and speed of the assay have been determined. With this assay it was shown that 50% of 36 serum specimens capable of neutralizing cell-free virions failed to inhibit syncytium formation. The assay can thus measure a distinct activity in HIV-1-immune human sera which is a subset of neutralization activity. Because of the potential role of this activity in the rate of disease progression and protective immune responses, the antifusion assay will be an important tool for the investigation of disease pathogenesis and for acquired immunodeficiency syndrome vaccine development. The assay can also be applied to the investigation of the pathogenesis of the fusion event at the cellular level. The ability to use absorbance measurements rather than syncytium counts as the endpoint facilitates direct computer-assisted data analysis, which expedites the performance of the assay.

Dextran sulphate (MW 5000 and 8000) and a polysulphated glycosaminoglycan (MW 10,000), at concentrations that provided complete protection in a homologous infection assay, failed to block syncytium formation and the resulting cytopathic effect when MT-2 cells were mixed with H9/HIV-1 cells. These substances also had no antiviral activity when added to cells, after virus challenge, at a time when binding and entry were complete. However, a high molecular weight (500,000) dextran sulphate blocked HIV-1 infection at both stages. Thus, the gp120-CD4 interactions mediating HIV-1 binding and HIV-1-induced syncytium formation are differentially affected by this class of polyanionic substances. Furthermore, size may be a determining factor in their potential application as anti-HIV treatment.

A 0.1 mg (base) dose of prazosin, a postsynaptic alpha- (alpha 1) adrenoceptor antagonist, in rabbits effected an early decrease in arterial blood pressure, normal intraocular pressure (IOP) and IOP artificially elevated by water loading. The late drug effects suppressed elevated IOP, but not normal IOP. The IOP effects of prazosin seem largely independent of the effect on blood pressure.

Ethanol suppressed, in a dose-related manner, glucose-induced insulin (IRI) release and thus delayed the disappearance of glucose from the blood of rats. Pretreatment with pyrazole, an alcohol dehydrogenase inhibitor, exacerbated the effect of ethanol on IRI release, glucose tolerance and glucagon (IRG) release. These results suggest that ethanol produces glucose intolerance by inhibiting glucose-induced IRI release and by augmenting IRG release. Moreover, these findings indicate that ethanol does not have to be metabolized completely in order to produce these effects.

A high-performance liquid chromatography (HPLC) technique was developed for the determination of radiolabeled triamcinolone acetonide (TAC), cortisol and their metabolites in rhesus monkey plasma, urine and tissue samples. After protein precipitation, the parent compounds and metabolites were simultaneously resolved using a single-column reversed-phase HPLC system. TAC was subsequently verified by mass spectrometry and TAC glucuronide was tentatively identified by enzymatic hydrolysis and mass spectrometry of the hydrolysis product. The endogenous hormones, cortisol and cortisone were presumptively identified by cochromatography with authentic standards on two different HPLC systems and positively identified by reverse-isotope recrystallization. Other metabolites of both compounds were detected by selective enzymatic hydrolysis and HPLC. This method is rapid and reproducible with a total recovery greater than 80%.

The late gestational age rhesus monkey was used to study the transplacental pharmacokinetics of radiolabeled triamcinolone acetonide (TAC) and cortisol. Tritiated-TAC and [14C]cortisol were administered simultaneously via the maternal radial vein were administered simultaneously via the maternal radial vein and blood samples were serially drawn from catheters implanted in both the maternal femoral artery and fetal umbilical vein and artery. High-performance liquid chromatography of the processed blood samples revealed that from 93 to 100% of the 3H in the fetal circulation was parent TAC, whereas only 14 to 49% of the 14C was cortisol during the 40-min period after dose administration. Fetal tissue samples taken at 3 hr after dose administration showed that 75 to 96% of the 3H present was TAC, whereas no cortisol was observed. TAC demonstrated dose-independent kinetics. Samples collected from the umbilical vein of the in situ placenta after fetectomy revealed that cortisol was extensively converted to cortisone by the placenta, whereas TAC was refractory to placental metabolism. This placental conversion of cortisol to cortisone and the further metabolism and conjugation of cortisol by the fetoplacental unit resulted in a fetal to maternal plasma cortisol ratio of 0.2. In contrast, the lack of placental or fetoplacental metabolism of TAC resulted in a fetal to maternal plasma TAC ratio of 0.6.

Pregnant rats were injected im with 0.5 mg/kg triamcinolone acetonide (TAC) on day 12, 13, or 14 of gestation and the fetuses were examined for cleft palate on day 20. All three TAC-treated groups showed an increased proportion of fetuses with cleft palate compared to an untreated control group. Only the group treated on day 13 showed a significant increase in the proportion of litters affected. This indicates that day 13 of gestation is the most sensitive day for cleft palate induction by TAC in the rat. Pregnant rats were then treated on day 13 of gestation with either TAC, triamcinolone (TA), or cortisol. TAC was 59 times as potent as TA in inducing cleft palate, with ED50 values of 1.1 mg/kg and 65 mg/kg respectively. Cortisol induced a significant increase in cleft palates at 500 mg/kg, but the efficacy of this compound was too low to calculate an ED50 and relative teratogenic potency value. Other developmental abnormalities including umbilical hernias, resorption, and fetal death resulted from TAC treatment. Fetal growth retardation was produced by all three compounds. The rank order of teratogenic potency was determined to be TAC greater than TA greater than cortisol.

Acute oral administration of ethanol (150 and 750 mg/100g) to fasted rats produced dose-related inhibition of arginine-induced insulin (IRI) release, an elevation of plasma glucagon (IRG) levels and minor effects on blood glucose. In contrast, chronic consumption of ethanol for 10 weeks augmented arginine-induced hyperglycemia and hperinsulinemia. Thus, acute ethanol administration decreased plasma IRI levels at both doses, presumably by suppressing beta cell function; whereas, function of the alpha cell and plasma IRG levels were increased, but only by the high dose of ethanol. In these experiments the effects exerted by ethanol on the pancreatic endocrine responses to arginine infusion varied according to: dose of ethanol administered; duration of exposure to ethanol; and state of nourishment of the subjects.

The object of the present study was to determine the maternal plasma pharmacokinetics of doxylamine (the antihistamine component of Bendectin) following Bendectin administration. Bendectin was administered daily, po, at a dosage approximately 10 times the maximum human therapeutic dosage (7 mg/kg/day) throughout organogenesis (approximately days 22 through 50 of gestation) to three cynomolgus monkeys, four rhesus monkeys, and five baboons. Two pharmacokinetic experiments were performed in each animal, one on the first day of treatment and one on the last day of treatment. Although this study was not designed specifically as a teratologic examination, no morphologic abnormalities were observed when the fetuses were examined on approximately day 100 of gestation. A single-compartment, parallel first- and second-order elimination model was used to analyze the data. Although considerable interindividual variation was evident, no significant differences between species were observed when the half-life for the absorption of doxylamine from the gut or the elimination of doxylamine and metabolites from the plasma were compared. The plasma elimination half-lives and the clearance values were not altered by the 29 days of Bendectin treatment for any of the species. Only the half-life for the absorption of doxylamine in the baboon was reduced by daily dosing with Bendectin, but this did not alter doxylamine elimination. Thus, the pharmacokinetics of doxylamine administered as Bendectin were similar in the three nonhuman primate species examined and were not altered by repeated daily administration.