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Amidines are an isostere of the amide bond and are completely unexplored in peptide secondary structure. This study marks the first investigation of the structural implications of amidines in folded helices. Amidines were found to engage in hydrogen-bonding interactions that are compatible with helical structure. The protic state of the amidine is also adaptive to local interactions, able to form stronger hydrogen bonds with proton donors or form the first example of a salt bridge along the peptide backbone to stabilize the C-terminus of the helical fold. The rationalization of this behavior was aided by our discovery that the basicity of amidines within peptide backbones can be significantly lower than previously assumed for small molecules. These findings compel investigation of amidines in peptide-drug design., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Thioimidates are a precursor and synthetic branch point to access either thioamide or amidine isosteres of the native amide (peptide bond). Previous syntheses of thioimidate-containing peptides were prone to side reactivity and required slow, cumbersome steps that were difficult to monitor. We describe a more efficient approach to directly couple thioimidates onto the growing peptide chain. This work also outlines optimal conditions for thioimidate formation on solid support and identifies potential off-target sites for alkylation that impact the choice of protecting group.

Background: The mean wait time for new patient appointments has been growing across specialties, including obstetrics and gynecology, in recent years. This study aimed to assess the impact of insurance type (Medicaid versus commercial insurance) on new patient appointment wait times in general obstetrics and gynecology practices., Methods: A cross-sectional study used covert mystery calls to general obstetrician gynecologists. Physicians were selected from the American College of Obstetricians and Gynecologists directory and stratified by districts to ensure nationwide representation. Wait times for new patient appointments were collected and analyzed., Results: Regardless of insurance type, the mean wait time for all obstetrician gynecologists was 29.9 business days. Medicaid patients experienced a marginally longer wait time of 4.8% (Ratio: 1.048). While no statistically significant difference in wait times based on insurance type was observed (P=0.39), the data revealed other impactful factors. Younger physicians and those in university-based practices had longer wait times. The gender of the physician also influenced wait times, with female physicians having a mean wait time of 34.7 days compared to 22.7 days for male physicians (P=0.03). Additionally, geographical variations were noted, with physicians in American College of Obstetricians and Gynecologists District I (Atlantic Provinces, CT, ME, MA, NH, RI, VT) having the longest mean wait times and those in District III (DE, NJ, PA) the shortest., Conclusions: While the type of insurance did not significantly influence the wait times for general obstetrics and gynecology appointments, physician demographic and geographic factors did.

Competing Interests: Declaration of competing interest The authors confirm no disclosures or conflicts of interest to report.

Synaptic structural plasticity, the expansion of dendritic spines in response to synaptic stimulation, is essential for experience-dependent plasticity and is driven by branched actin polymerization. The WAVE regulatory complex (WRC) is confined to nanodomains at the postsynaptic membrane where it catalyzes actin polymerization. As the netrin/RGM receptor Neogenin is a critical regulator of the WRC, its nanoscale organization may be an important determinant of WRC nanoarchitecture and function. Using super-resolution microscopy, we reveal that Neogenin is highly organized on the spine membrane at the nanoscale level. We show that Neogenin binding to the WRC promotes co-clustering into nanodomains in response to brain-derived neurotrophic factor (BDNF), indicating that nanoclustering occurs in response to synaptic stimulation. Disruption of Neogenin/WRC binding not only prevents BDNF-mediated actin remodeling but also inhibits BDNF-induced calcium signaling. We conclude that the assembly of Neogenin/WRC nanodomains is a prerequisite for BDNF-mediated structural and synaptic plasticity., Competing Interests: The authors declare no conflicts of interest., (© 2024 The Authors.)

Background and Objectives: Despite advances in the prevention of rhesus (Rh)(D) alloimmunization, alloantibodies to Rh(D) and non-Rh(D) red blood cell antigens continue to be detected in ∼4% of US pregnancies and can result in hemolytic disease of the fetus and newborn (HDFN). Recent reports on HDFN lack granularity and are unable to provide antibody-specific outcomes. The objective of this study was to calculate the frequency of alloimmunization in our large hospital system and summarize the outcomes based on antibody specificity, titer, and other clinical factors., Methods: We identified all births in a 6-year period after a positive red blood cell antibody screen result during pregnancy and summarized their characteristics and outcomes., Results: A total of 707 neonates were born after a positive maternal antibody screen result (3.0/1000 live births). In 31 (4%), the positive screen result was due to rhesus immune globulin alone. Of the 676 neonates exposed to alloantibodies, the direct antibody test (DAT) result was positive, showing antigen-positivity and evidence of HDFN in 37% of those tested. Neonatal disease was most severe with DAT-positive anti-Rh antibodies (c, C, D, e, E). All neonatal red blood cell transfusions (15) and exchange transfusions (6) were due to anti-Rh alloimmunization. No neonates born to mothers with anti-M, anti-S, anti-Duffy, anti-Kidd A, or anti-Lewis required NICU admission for hyperbilirubinemia or transfusion., Conclusions: Alloimmunization to Rh-group antibodies continues to cause a majority of the severe HDFN cases in our hospital system. In neonates born to alloimmunized mothers, a positive DAT result revealing antigen-positivity is the best predictor of anemia and hyperbilirubinemia., (Copyright © 2024 by the American Academy of Pediatrics.)

Imidazolones represent an important class of heterocycles present in a wide range of pharmaceuticals, metabolites, and bioactive natural products and serve as the active chromophore in green fluorescent protein. Recently, imidazolones have received attention for their ability to act as a nonaromatic amide bond bioisotere which improves pharmacological properties. Herein, we present a tandem amidine installation and cyclization with an adjacent ester to yield (4 H )-imidazolone products. Using amino acid building blocks, we can access the first examples of α-chiral imidazolones that have been previously inaccessible. Additionally, our method is amenable to on-resin installation which can be seamlessly integrated into existing solid-phase peptide synthesis protocols. Finally, we show that peptide imidazolones are potent cis -amide bond surrogates that preorganize linear peptides for head-to-tail macrocyclization. This work represents the first general approach to the backbone and side-chain insertion of imidazolone bioisosteres at various positions in linear and cyclic peptides.

Thioamides, amidines, and heterocycles are three classes of modifications that can act as peptide-bond isosteres to alter the peptide backbone. Thioimidate protecting groups can address many of the problematic synthetic issues surrounding installation of these groups. Historically, amidines have received little attention in peptides due to limitations in methods to access them. The first robust and general procedure for the introduction of amidines into peptide backbones exploits the utility of thioimidate protecting groups as a means to side-step reactivity that ultimately renders existing methods unsuitable for the installation of amidines along the main-chain of peptides. Further, amidines formed on-resin can be reacted to form (4H)-imidazolone heteorcycles which have recently been shown to act as cis-amide isosteres. General methods for heterocyclic installation capable of geometrically restricting peptide conformation are also under-developed. This work is significant because it describes a generally applicable and divergent approach to access unexplored peptide designs and architectures., (Copyright © 2024. Published by Elsevier Inc.)

Structural plasticity, the ability of dendritic spines to change their volume in response to synaptic stimulation, is an essential determinant of synaptic strength and long-term potentiation (LTP), the proposed cellular substrate for learning and memory. Branched actin polymerization is a major force driving spine enlargement and sustains structural plasticity. The WAVE Regulatory Complex (WRC), a pivotal branched actin regulator, controls spine morphology and therefore structural plasticity. However, the molecular mechanisms that govern WRC activation during spine enlargement are largely unknown. Here we identify a critical role for Neogenin and its ligand RGMa (Repulsive Guidance Molecule a) in promoting spine enlargement through the activation of WRC-mediated branched actin remodeling. We demonstrate that Neogenin regulates WRC activity by binding to the highly conserved Cyfip/Abi binding pocket within the WRC. We find that after Neogenin or RGMa depletion, the proportions of filopodia and immature thin spines are dramatically increased, and the number of mature mushroom spines concomitantly decreased. Wildtype Neogenin, but not Neogenin bearing mutations in the Cyfip/Abi binding motif, is able to rescue the spine enlargement defect. Furthermore, Neogenin depletion inhibits actin polymerization in the spine head, an effect that is not restored by the mutant. We conclude that RGMa and Neogenin are critical modulators of WRC-mediated branched actin polymerization promoting spine enlargement. This study also provides mechanistic insight into Neogenin's emerging role in LTP induction., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Sempert, Shohayeb, Lanoue, O’Brien, Flores and Cooper.)

Objectives: To determine whether neonatal conjugated or direct bilirubin levels were elevated in infants with biliary atresia (BA) and to estimate the number of newborns who would have positive screens in the nursery necessitating repeat testing after discharge., Study Design: We used administrative data from a large integrated healthcare network in Utah to identify newborns who had a fractionated bilirubin recorded during birth admission from 2005 through 2019. Elevated conjugated bilirubin was defined as greater than 0.2 mg/dL and direct bilirubin was defined as greater than 0.5 mg/dL (>97.5th percentile for the assays). We performed simulations to estimate the anticipated number of false-positive screens., Results: There were 32 cases of BA and 468 161 live births during the study period (1/14 700). There were 252 892 newborns with fractionated bilirubin assessed, including 26 of those subsequently confirmed to have BA. Conjugated or direct bilirubin was elevated in all 26 infants with BA and an additional 3246 newborns (1.3%) without BA. Simulated data suggest 9-21 per 1000 screened newborns will have an elevated conjugated or direct bilirubin using laboratory-based thresholds for a positive screen. Screening characteristics improved with higher thresholds without increasing false-negative tests., Conclusions: This study validates the previous findings that conjugated or direct bilirubin are elevated in the newborn period in patients with BA. A higher threshold for conjugated bilirubin improved screening performance. Future studies are warranted to determine the optimal screening test for BA and to assess the effectiveness and cost-effectiveness of implementing such a program., (Copyright © 2023 Elsevier Inc. All rights reserved.)

We present the Canadian Open Neuroscience Platform (CONP) portal to answer the research community's need for flexible data sharing resources and provide advanced tools for search and processing infrastructure capacity. This portal differs from previous data sharing projects as it integrates datasets originating from a number of already existing platforms or databases through DataLad, a file level data integrity and access layer. The portal is also an entry point for searching and accessing a large number of standardized and containerized software and links to a computing infrastructure. It leverages community standards to help document and facilitate reuse of both datasets and tools, and already shows a growing community adoption giving access to more than 60 neuroscience datasets and over 70 tools. The CONP portal demonstrates the feasibility and offers a model of a distributed data and tool management system across 17 institutions throughout Canada., (© 2023. The Author(s).)

Amidines are a structural surrogate for peptide bonds, yet have received considerably little attention in peptides due to limitations in existing methods to access them. The synthetic strategy developed in this study represents the first robust and general procedure for the introduction of amidines into the peptide backbone. We exploit and further develop the utility and efficiency of thioimidate protecting groups as a means to side-step reactivity that ultimately renders existing methods unsuitable for the installation of amidines along the main-chain of peptides. This work is significant because it describes a generally applicable path to access unexplored peptide designs and architectures for new therapeutics made possible by the unique properties of amidines.

Interactions between plants and soil microbes influence plant nutrient transformations, including nitrogen (N) fixation, nutrient mineralization, and resource exchanges through fungal networks. Physical disturbances to soils can disrupt soil microbes and associated processes that support plant and microbial productivity. In low resource drylands, biological soil crusts ("biocrusts") occupy surface soils and house key autotrophic and diazotrophic bacteria, non-vascular plants, or lichens. Interactions among biocrusts, plants, and fungal networks between them are hypothesized to drive carbon and nutrient dynamics; however, comparisons across ecosystems are needed to generalize how soil disturbances alter microbial communities and their contributions to N pools and transformations. To evaluate linkages among plants, fungi, and biocrusts, we disturbed all unvegetated surfaces with human foot trampling twice yearly from 2013-2019 in dry conditions in cyanobacteria-dominated biocrusts in the Chihuahuan Desert grassland and shrubland ecosystems. After 5 years, disturbance decreased the abundances of cyanobacteria (especially Microcoleus steenstrupii clade) and N-fixers (Scytonema sp., and Schizothrix sp.) by >77% and chlorophyll a by up to 55% but, conversely, increased soil fungal abundance by 50% compared with controls. Responses of root-associated fungi differed between the two dominant plant species and ecosystem types, with a maximum of 80% more aseptate hyphae in disturbed than in control plots. Although disturbance did not affect 15 N tracer transfer from biocrusts to the dominant grass, Bouteloua eriopoda, disturbance increased available soil N by 65% in the shrubland, and decreased leaf N of B. eriopoda by up to 16%, suggesting that, although rapid N transfer during peak production was not affected by disturbance, over the long-term plant nutrient content was disrupted. Altogether, the shrubland may be more resilient to detrimental changes due to disturbance than grassland, and these results demonstrated that disturbances to soil microbial communities have the potential to cause substantial changes in N pools by reducing and reordering biocrust taxa., (© 2022 The Ecological Society of America.)

In order to reduce iron deficiency in neonates at-risk for iron deficiency, we implemented a guideline to increase the consistency of early iron supplementation in infants of diabetic mothers, small for gestational age neonates and very low birthweight premature neonates. Three years following implementation we performed a retrospective analysis in order to assess adherence to the guideline and to compare timing of early iron supplementation and reticulocyte-hemoglobin (RET-He) values at one month of life in at-risk infants. Adherence with early iron supplementation guidelines was 73.4% (399/543) with 51% (275/543) having RET-He values obtained at one month. Despite good adherence, 16% (44/275) had RET-He <25 pg (5th percentile for gestational age). No infants receiving red blood cell transfusion (0/20) had RET-He <25 pg vs. 26.1% (40/153) of those treated with darbepoetin (p < 0.001). There was no evidence of increased feeding intolerance (episodes of emesis/day) with early iron supplementation., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Quantum dot surfaces can have a substantial effect on their physical, chemical, and optoelectronic properties. When the chemistry that occurs at the surface of nanocrystals is studied, critical insights can be gained into the fundamental structural, thermodynamic, and optical properties of quantum dot materials providing a valuable guide for how to best adapt them for desired applications. Colloidal quantum dots are often terminated with organic ligands that consist of a long aliphatic chain and a head group that binds tightly to the nanocrystal surface. While extensive work has been done to understand how ligand head groups influence quantum dot properties, studies to unravel the influence of the organic ligand tail on ligands and surface reaction equilibria are incomplete. To further investigate the driving forces of quantum dot surface modification, a series of ligand exchange reactions with oleic acid were performed on indium phosphide quantum dots, initially terminated with straight-chain carboxylates of variable lengths. The reaction was monitored using isothermal titration calorimetry and 1 H NMR to determine the extent of each reaction and its associated thermodynamics. From these measurements, interligand interactions were observed to be dependent on the length of the straight-chain ligand. A modified Ising model was used to investigate the enthalpic and entropic effects contributing to these ligand exchanges and reveal that interligand interactions play a much larger role than previously thought. Additional experimentation with phosphonic acid ligand exchange reveals complexity in the reaction mechanism but further illustrates the significant impact of ligand tail group length on thermodynamics, even in cases where there is a large difference in head group binding energy.

Background: The traditional concept that heritability occurs exclusively from the transfer of germline-restricted genetics is being challenged by the increasing accumulation of evidence confirming the existence of experience-dependent transgenerational inheritance. However, questions remain unanswered as to how heritable information can be passed from somatic cells. Previous studies have implicated the critical involvement of RNA in heritable transgenerational effects, and the high degree of mobility and genomic impact of RNAs in all organisms is an attractive model for the efficient transfer of genetic information., Results: We hypothesized that RNA may be transported from a somatic tissue, in this case the brain, of an adult male mouse to the germline, and subsequently to embryos. To investigate this, we injected one hemisphere of the male mouse striatum with an AAV1/9 virus expressing human pre-MIR941 (MIR941). After 2, 8 and 16 weeks following injection, we used an LNA-based qPCR system to detect the presence of virus and human MIR941 in brain, peripheral tissues and embryos, from injected male mice mated with uninjected females. Virus was never detected outside of the brain. Verification of single bands of the correct size for MIR941 was performed using Sanger sequencing while quantitation demonstrated that a small percentage (~ 1-8%) of MIR941 is transported to the germline and to embryos in about a third of the cases., Conclusions: We show that somatic RNA can be transported to the germline and passed on to embryos, thereby providing additional evidence of a role for RNA in somatic cell-derived intergenerational effects.

A novel macrocyclic host molecule was synthesized that forms in a single step from commercially available starting materials. The core of the macrocycle backbone possesses two quinone rings and, thus, it is redox-active. Host-guest binding involving the clip-shaped cavity indicates selective binding of pyridine N-oxides based on the electron density of and steric bulk around the anionic oxygen., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A phase transition within the ligand shell of core/shell quantum dots is studied in the prototypical system of colloidal CdSe/CdS quantum dots with a ligand shell composed of bound oleate (OA) and octadecylphosphonate (ODPA). The ligand shell composition is tuned using a ligand exchange procedure and quantified through proton NMR spectroscopy. Temperature-dependent photoluminescence spectroscopy reveals a signature of a phase transition within the organic ligand shell. Surprisingly, the ligand order to disorder phase transition triggers an abrupt increase in the photoluminescence quantum yield (PLQY) and full-width at half-maximum (FWHM) with increasing temperature. The temperature and width of the phase transition show a clear dependence on ligand shell composition, such that QDs with higher ODPA fractions have sharper phase transitions that occur at higher temperatures. In order to gain a molecular understanding of the changes in ligand ordering, Fourier transform infrared and vibrational sum frequency generation spectroscopies are performed. These measurements confirm that an order/disorder transition in the ligand shell tracks with the photoluminescence changes that accompany the ligand phase transition. The phase transition is simulated through a lattice model that suggests that the ligand shell is well-mixed and does not have completely segregated domains of OA and ODPA. Furthermore, we show that the unsaturated chains of OA seed disorder within the ligand shell.

Background: Humans have adapted to widespread changes during the past 2 million years in both environmental and lifestyle factors. This is evident in overall body alterations such as average height and brain size. Although we can appreciate the uniqueness of our species in many aspects, molecular variations that drive such changes are far from being fully known and explained. Comparative genomics is able to determine variations in genomic sequence that may provide functional information to better understand species-specific adaptations. A large number of human-specific genomic variations have been reported but no currently available dataset comprises all of these, a problem which contributes to hinder progress in the field., Results: Here we critically update high confidence human-specific genomic variants that mostly associate with protein-coding regions and find 856 related genes. Events that create such human-specificity are mainly gene duplications, the emergence of novel gene regions and sequence and structural alterations. Functional analysis of these human-specific genes identifies adaptations to brain, immune and metabolic systems to be highly involved. We further show that many of these genes may be functionally associated with neural activity and generating the expanded human cortex in dynamic spatial and temporal contexts., Conclusions: This comprehensive study contributes to the current knowledge by considerably updating the number of human-specific genes following a critical bibliographic survey. Human-specific genes were functionally assessed for the first time to such extent, thus providing unique information. Our results are consistent with environmental changes, such as immune challenges and alterations in diet, as well as neural sophistication, as significant contributors to recent human evolution.

Background: An emergency-release blood transfusion (ERBT) protocol (uncrossmatched type O-negative red blood cells, AB plasma, AB platelets) is critical for neonatology practice. However, few reports of emergency transfusions are available. We conducted an ERBT quality improvement project as a basis for progress., Study Design and Methods: For each ERBT in the past 8 years, we logged indications, products, locations and timing of the transfusions, and outcomes., Results: One hundred forty-nine ERBTs were administered; 42% involved a single blood product, and 58% involved two or more. The incidence was 6.25 ERBT per 10,000 live births, with a higher rate (9.52 ERBT/10,000) in hospitals with a Level 3 neonatal intensive care unit (NICU) (p < 0.001). Seventy percent of ERBTs were administered in a NICU and 30% in a delivery room, operating room, or emergency department. Indications were abruption/previa (32.2%), congenital anemia (i.e., fetomaternal hemorrhage; 15.4%), umbilical cord accident (i.e., velamentous insertion; 15.0%), and bleeding/coagulopathy (12.8%). Fifty-eight percent of those with hemorrhage before birth did not have a hemoglobin value reported on the umbilical cord gas; thus, anemia was not recognized initially. None of the 149 ERBTs were administered using a blood warmer. The mortality rate of recipients was 35%., Conclusion: Based on our findings, we recommend including a hemoglobin value with every cord blood gas after emergency delivery to rapidly identify fetal anemia. We also discuss two potential improvements for future testing: 1) the use of a warming device for massive transfusion of neonates and 2) the use of low-titer group O cold-stored whole blood for massive hemorrhage in neonates., (© 2019 AABB.)

Hidradenitis suppurativa (HS) is a chronic inflammatory skin disorder. A genetic component in the pathogenesis is highly likely considering that ~30% to 40% of patients with HS report a family history of the disease. The genetic mutations related to HS that have been reported to date suggest HS can be inherited as a monogenic trait because of a defect in either the Notch signaling pathway or inflammasome function, or as a polygenic disorder resulting from defects in genes regulating epidermal proliferation, ceramide production, or in immune system function. This review provides a summary of genetic mutations reported in patients diagnosed with HS and discusses the mechanisms by which these genes are involved in its pathogenesis.

Objective: Hypothermia occurs frequently in the first minutes after birth in preterm infants. Hyperthermia also occurs, often as a consequence of efforts to provide thermal support. Both hypothermia and hyperthermia are potentially harmful. Our objective was to examine the distribution of admission temperatures of very low birth weight (VLBW) infants, the effect of gestational age on admission temperatures, and the time required for correction of low temperatures., Methods: Admission axillary temperatures were retrieved from the medical records for all VLBW infants born in our hospital during a 5-year period. The temperatures were classified as severe (<35.0 °C), moderate (35.0-35.9 °C), or mild (36.0-36.4 °C) hypothermia, normothermia (36.5-37.4 °C), or hyperthermia (≥37.5 °C). The relationship between gestational age and admission temperature was examined. In addition, we analyzed the time required for normalization of low temperatures., Results: Overall, 12% of infants were severely hypothermic, 40% moderately hypothermic, 27% mildly hypothermic, 19% normothermic, and 2% hyperthermic. Gestational age was inversely related to hypothermia risk and to the time required for recovery to normothermia., Conclusion: Admission hypothermia is common among VLBW infants and is affected by gestational age.

Objective: ABO hemolytic disease occurs among neonates with blood groups A or B delivered to group O women. Extreme neonatal hyperbilirubinemia due to ABO disease has been reported, but its frequency is not well known. We sought to determine the odds of developing severe ABO hemolytic disease in the 13 years since adopting universal bilirubin screening/management in the Intermountain Healthcare system., Study Design: We conducted a retrospective analysis of neonates born between 2004 and 2016, defining "severe hemolytic disease" as; (1) total serum bilirubin (TSB) >25 mg/dL, or (2) hospital readmission for jaundice, or (3) bilirubin encephalopathy. Neonates born to group O (+) mothers were included and considered either; (1) Controls (not at risk for ABO disease because they were group O), (2) Study subjects (at risk for ABO disease because they were group A or B)., Results: Of 400,531 live births, 47% were to group O women; 86% of whom were group O (+). Overall, 42,529 (27%) neonates born to group O (+) women had their blood group determined; 29,729 (68%) were O, 10,682 (25%) A, and 3109 (7%) B. Peak TSBs during the first 10 days were higher in group A (11.0 ± 4.2 mg/dL) and B (11.5 ± 4.3) than group O neonates (10.3 ± 4.1). However the relative risks of a TSB ≥25 mg/dL, readmission for jaundice, or kernicterus, were the same in the control vs. study groups., Conclusions: In our health system, severe hemolytic disease in neonates born to group O (+) woman is not more likely in group A or B neonates than in controls (group O). We recognize that in other practices, particularly those who do not have a universal bilirubin screening/management program, ABO hemolytic disease severity might be different than in our system.

There is a strong association between cannabis use and schizophrenia but the underlying cellular links are poorly understood. Neurons derived from human-induced pluripotent stem cells (hiPSCs) offer a platform for investigating both baseline and dynamic changes in human neural cells. Here, we exposed neurons derived from hiPSCs to Δ 9 -tetrahydrocannabinol (THC), and identified diagnosis-specific differences not detectable in vehicle-controls. RNA transcriptomic analyses revealed that THC administration, either by acute or chronic exposure, dampened the neuronal transcriptional response following potassium chloride (KCl)-induced neuronal depolarization. THC-treated neurons displayed significant synaptic, mitochondrial, and glutamate signaling alterations that may underlie their failure to activate appropriately; this blunted response resembles effects previously observed in schizophrenia hiPSC- derived neurons. Furthermore, we show a significant alteration in THC-related genes associated with autism and intellectual disability, suggesting shared molecular pathways perturbed in neuropsychiatric disorders that are exacerbated by THC.

Various mutations in the genes encoding alpha spectrin (SPTA1) or beta spectrin (SPTB) are known to cause erythrocyte membrane disorders, sometimes associated with severe neonatal jaundice and anemia. We used a next-generation sequencing panel to evaluate 3 unrelated neonates who had puzzling cases of nonimmune hemolytic jaundice. In each case, we identified novel mutations in either SPTA1 or SPTB. Correlating erythrocyte morphology, clinical course, and computational analysis, we submit that each of the 3 variants is a probable pathogenic cause of the hereditary hemolytic conditions in these patients. We hope other pediatric practitioners caring for neonates with what appears to be idiopathic severe neonatal hyperbilirubinemia will look for spectrin variants as a possible cause, because additional cases with these specific variants along with this clinical phenotype are needed to confirm our postulate that these 3 cases are indeed pathogenic mutations.

Professional societies have published recommendations for iron dosing of preterm neonates, but differences exist between guidelines. To help develop standardized guidelines, we performed a 10-year analysis of iron dosing in groups at risk for iron deficiency: IDM (infants of diabetic mothers), SGA (small for gestational age), and VLBW premature neonates (very low birth weight, <1500 g). We analyzed iron dosing after red cell transfusions and erythropoiesis-stimulating agents (ESA). Of IDM, 11.8% received iron in the hospital; 9.8% of SGA and 27.1% of VLBW neonates received iron. Twenty percent of those who received iron had it started by day 14; 63% by 1 month. Supplemental iron was stopped after red cell transfusions in 73% of neonates receiving iron. An ESA was administered to 1677, of which 33% received iron within 3 days. This marked variation indicates that a consistent approach is needed, and using this report and a literature review, we standardized our iron-dosing guidelines., Competing Interests: Declaration of Conflicting Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Objective: Small-for-gestational-age (SGA) neonates, infants of diabetic mothers (IDM) and very-low-birth weight premature neonates (VLBW) are reported to have increased risk for developing iron deficiency and possibly associated neurocognitive delays., Study Design: We conducted a pilot study to assess iron status at birth in at-risk neonates by measuring iron parameters in umbilical cord blood from SGA, IDM, VLBW and comparison neonates., Results: Six of the 50 infants studied had biochemical evidence of iron deficiency at birth. Laboratory findings consistent with iron deficiency were found in one SGA, one IDM, three VLBW, and one comparison infant. None of the infants had evidence of iron deficiency anemia., Conclusions: Evidence of biochemical iron deficiency at birth was found in 17% of screened neonates. Studies are needed to determine whether these infants are at risk for developing iron-limited erythropoiesis, iron deficiency anemia or iron-deficient neurocognitive delay.

Objective: To evaluate neonatal survival after prolonged preterm premature rupture of membranes (PROM) in the era of antenatal corticosteroids, surfactant, and inhaled nitric oxide., Methods: A single-center retrospective cohort study of neonates born from 2002-2011 after prolonged (1 week or more) preterm (less than 24 weeks of gestation) rupture of membranes was performed. The primary outcome was survival to discharge. Neonates whose membranes ruptured less than 24 hours before delivery (n=116) were matched (2:1) on gestational age at birth, sex, and antenatal corticosteroid exposure with neonates whose membranes ruptured 1 week or more before delivery (n=58). Analysis used conditional logistic regression for categorical data and Wilcoxon signed rank test for continuous data., Results: The prolonged preterm PROM exposed and unexposed cohorts had survival rates of 90% and 95%, respectively, although underpowered to assess the statistical significance (P=.313). Exposed neonates were more likely have pulmonary hypoplasia (26/58 exposed, 1/114 unexposed, P<.001), pulmonary hypertension (21/56 exposed, 10/112 unexposed, P<.001), and pulmonary air leak (21/58 exposed, 14/114 unexposed, P<.001). Gestational age at rupture (20.4 weeks exposed, 22.3 weeks unexposed, P=.189), length of rupture (3.7 weeks exposed, 6.4 weeks unexposed, P=.717), and lowest maximal vertical pocket before 24 weeks of gestation (0 cm exposed, 1.4 cm unexposed, P=.114) did not discriminate between survivors and nonsurvivors after exposure to prolonged preterm PROM., Conclusion: With antenatal steroid exposure and aggressive pulmonary management, survival to discharge after prolonged preterm PROM was 90%. Pulmonary morbidities were common. Of note, the data were limited to women who remained pregnant 1 week or longer after rupture of membranes.

The organelle genome database GOBASE, now in its 21st release (June 2008), contains all published mitochondrion-encoded sequences (approximately 913,000) and chloroplast-encoded sequences (approximately 250,000) from a wide range of eukaryotic taxa. For all sequences, information on related genes, exons, introns, gene products and taxonomy is available, as well as selected genome maps and RNA secondary structures. Recent major enhancements to database functionality include: (i) addition of an interface for RNA editing data, with substitutions, insertions and deletions displayed using multiple alignments; (ii) addition of medically relevant information, such as haplotypes, SNPs and associated disease states, to human mitochondrial sequence data; (iii) addition of fully reannotated genome sequences for Escherichia coli and Nostoc sp., for reference and comparison; and (iv) a number of interface enhancements, such as the availability of both genomic and gene-coding sequence downloads, and a more sophisticated literature reference search functionality with links to PubMed where available. Future projects include the transfer of GOBASE features to NCBI/GenBank, allowing long-term preservation of accumulated expert information. The GOBASE database can be found at http://gobase.bcm.umontreal.ca/. Queries about custom and large-scale data retrievals should be addressed to gobase@bch.umontreal.ca.

Intrauterine growth restriction (IUGR) increases the incidence of chronic lung disease (CLD). The molecular mechanisms responsible for IUGR-induced acute lung injury that predispose the IUGR infant to CLD are unknown. p53, a transcription factor, plays a pivotal role in determining cellular response to stress by affecting apoptosis, cell cycle regulation, and angiogenesis, processes required for thinning of lung mesenchyme. Because thickened lung mesenchyme is characteristic of CLD, we hypothesized that IUGR-induced changes in lung growth are associated with alterations in p53 expression and/or modification. We induced IUGR through bilateral uterine artery ligation of pregnant rats. Uteroplacental insufficiency significantly decreased serine-15-phosphorylated (serine-15P) p53, an active form of p53, in IUGR rat lung. Moreover, we found that decreased phosphorylation of lung p53 serine-15 localized to thickened distal air space mesenchyme. We also found that IUGR significantly decreased mRNA for targets downstream of p53, specifically, proapoptotic Bax and Apaf, as well as Gadd45, involved in growth arrest, and Tsp-1, involved in angiogenesis. Furthermore, we found that IUGR significantly increased mRNA for Bcl-2, an antiapoptotic gene downregulated by p53. We conclude that in IUGR rats, uteroplacental insufficiency induces decreased lung mesenchymal p53 serine-15P in association with distal lung mesenchymal thickening. We speculate that decreased p53 serine-15P in IUGR rat lungs alters lung phenotype, making the IUGR lung more susceptible to subsequent injury.

The TBestDB database contains approximately 370,000 clustered expressed sequence tag (EST) sequences from 49 organisms, covering a taxonomically broad range of poorly studied, mainly unicellular eukaryotes, and includes experimental information, consensus sequences, gene annotations and metabolic pathway predictions. Most of these ESTs have been generated by the Protist EST Program, a collaboration among six Canadian research groups. EST sequences are read from trace files up to a minimum quality cut-off, vector and linker sequence is masked, and the ESTs are clustered using phrap. The resulting consensus sequences are automatically annotated by using the AutoFACT program. The datasets are automatically checked for clustering errors due to chimerism and potential cross-contamination between organisms, and suspect data are flagged in or removed from the database. Access to data deposited in TBestDB by individual users can be restricted to those users for a limited period. With this first report on TBestDB, we open the database to the research community for free processing, annotation, interspecies comparisons and GenBank submission of EST data generated in individual laboratories. For instructions on submission to TBestDB, contact tbestdb@bch.umontreal.ca. The database can be queried at http://tbestdb.bcm.umontreal.ca/.

Background: Dermatology signs serve as important clues to primary skin disorders and internal conditions., Objective and Methods: To highlight major cutaneous signs based on a MEDLINE literature search from 1966 to March 2006., Results and Conclusions: A multitude of signs exist in dermatology. Appreciation and knowledge of cutaneous signs will enhance the care of patients with dermatologic manifestations.

The organelle genome database GOBASE is now in its twelfth release, and includes 350,000 mitochondrial sequences and 118,000 chloroplast sequences, roughly a 3-fold expansion since previously documented. GOBASE also includes a fully reannotated genome sequence of Rickettsia prowazekii, one of the closest bacterial relatives of mitochondria, and will shortly expand to contain more data from bacteria from which organelles originated. All these sequences are now accessible through a single unified interface. Enhancements to the functionality of GOBASE include addition of pages for RNA structures and a page compiling data about the taxonomic distribution of organelle-encoded genes; incorporation of Gene Ontology terms; addition of features deduced from incomplete annotations to sequences in GenBank; marking of type examples in cases where single genes in single species are oversampled within GenBank; and addition of graphics illustrating gene structure and the position of neighbouring genes on a sequence. The database has been reimplemented in PostgreSQL to facilitate development and maintenance, and structural modifications have been made to speed up queries, particularly those related to taxonomy. The GOBASE database can be queried at http://gobase.bcm.umontreal.ca/ and inquiries should be directed to gobase@bch.umontreal.ca.

Chemotherapeutic agents may induce a wide variety of adverse mucocutaneous effects, including nail changes. We present a case of atypical onycholysis, associated with subungual abscess formation, paronychia and pyogenic granuloma resulting from the use of mitozantrone, an antineoplastic cytotoxic agent, in the treatment of metastatic prostate cancer.

Formation of the pulmonary vasculature has been described as occurring by outgrowth of existing vessels (angiogenesis), de novo formation of new vessels (vasculogenesis), or a combination of both processes. Uncertainty about the contribution of angiogenesis and vasculogenesis to pulmonary vascular formation is partly due to methodologic approaches. Evidence in favor of angiogenesis stems from studies that used vascular-filling methods. Such methods identify only directly continuous lumina. Evidence for vasculogenesis has been provided by the use of molecular markers of blood vessel endothelium. Use of both methods has not been combined in the same species, however. We hypothesized, based on published evidence from quail and mouse, that chick pulmonary vascular formation occurs by vasculogenesis. To test that hypothesis, we used vascular filling, serial section, and immunohistochemical methods to analyze the developing lungs of chick embryos from Hamburger and Hamilton stages 20 to 43. Vascular filling suggested that the lumen of the pulmonary arteries sprouted from the sixth pharyngeal arch arteries. However, serial sections and immunohistochemical localization of fetal liver kinase-1 protein, the receptor for vascular endothelial growth factor, showed that the pulmonary arterial tree formed from endothelial cell precursors and coalescence of isolated blood vessels in the mediastinal splanchnic mesenchyme centrally to the developing lung tissue distally. Pulmonary veins grew from the left atrium to the developing lungs. Pulmonary blood vessel formation occurred continuously throughout the embryonic period studied. Our results show that vasculogenesis is the main process by which the pulmonary vasculature forms in the developing chick embryo., (Copyright 2005 Wiley-Liss, Inc.)

GOBASE is a relational database containing integrated sequence, RNA secondary structure and biochemical and taxonomic information about organelles. GOBASE release 6 (summer 2002) contains over 130 000 mitochondrial sequences, an increase of 37% over the previous release, and more than 30 000 chloroplast sequences in a new auxiliary database. To handle this flood of new data, we have designed and implemented GOpop, a Java system for population and verification of the database. We have also implemented a more powerful and flexible user interface using the PHP programming language. http://megasun.bch.umontreal.ca/gobase/gobase.html.

Peptidases (often termed proteases) are of great relevance to biology, medicine, and biotechnology. This practical importance creates a need for an integrated source of information about peptidases. In the MEROPS database (www.merops.ac.uk), peptidases are classified by structural similarities in the parts of the molecules responsible for their enzymatic activity. They are grouped into families on the basis of amino acid sequence homology, and the families are assembled into clans in light of evidence that they share common ancestry. The evidence for clan-level relationships usually comes from similarities in tertiary structure, but we suggest that secondary structure profiles may also be useful in the future. The classification forms a framework around which a wealth of supplementary information about the peptidases is organized. This includes images of three-dimensional structures, alignments of matching human and mouse ESTs, comments on biomedical relevance, human and other gene symbols, and literature references linked to PubMed. For each family, there is an amino acid sequence alignment and a dendrogram. There is a list of all peptidases known from each of over 1000 species, together with summary data for the distributions of the families and clans throughout the major groups of organisms. A set of online searches provides access to information about the location of peptidases on human chromosomes and peptidase substrate specificity., (Copyright 2001 Academic Press.)

Osteoclast differentiation and activation is controlled, at least in part, by the counterbalancing influences of osteoprotegerin ligand (OPGL) and osteoprotegerin (OPG). Nonsteroidal anti-inflammatory drugs have been shown to inhibit bone loss in vivo and bone resorption in vitro, and this is associated with a loss of osteoclasts from the bone surface. We test the hypothesis that OPG mediates the inhibition of osteoclast activity that occurs with indomethacin in the mouse calvaria. Recombinant human OPG, like indomethacin, was found to cause osteoclasts to detach from the bone surface and attach to the adjacent endocranial membrane (periosteum). Recombinant human OPG also inhibited the stimulatory effect of prostaglandin E2 (PGE2), parathyroid hormone (PTH), and 1,25-dihydroxyvitamin D3 (1,25D3) on osteoclast adhesion to bone after an incubation with indomethacin. A function-blocking antibody to OPG and soluble human OPGL both inhibited the effect of indomethacin, leaving active osteoclasts on the bone. OPG activity was detected in the culture medium from indomethacin-treated bones and PTH, PGE2, 1,25D3, and dexamethasone all inhibited the production of OPG activity. We conclude that, in the absence of specific stimulators of bone resorption, OPG is produced by the mouse calvaria in vitro, which inhibits bone resorption by causing osteoclasts to detach from the bone surface.

The stimulators of bone resorption, prostaglandin E(2) (PGE(2)) and 1,25-dihydroxyvitamin D(3) (1,25D(3)), act through osteoblast-like cells to activate osteoclasts. One candidate for the intermediary produced by osteoblasts that subsequently stimulates the osteoclast is osteoprotegerin ligand (OPGL). OPGL has been shown to stimulate osteoclast differentiation and activation. The aim of the work reported here was to determine if soluble recombinant extracellular domain of human OPGL would bring about the change in osteoclast adhesion from the periosteum of mouse calvaria to the adjacent bone surface that occurs with the above-mentioned stimulators of resorption. This change in adherence or translocation of osteoclasts onto the bone surface required the expression and functioning of the integrin subunit, beta 3. We show that this soluble OPGL, like PGE(2) and 1,25D(3), stimulated the release of osteoclasts from the periosteum and their adherence to the bone surface accompanied by an increase in staining for immunolocalized integrin subunit beta 3. Recombinant human osteoprotegerin (OPG), which binds strongly to OPGL, inhibited this translocation of osteoclasts that occurred with PGE(2) and 1,25D(3), leaving integrin beta-3-negative osteoclasts on the periosteum. PGE(2) and 1,25D(3) increased the expression of messenger RNA for OPGL compared with indomethacin-treated controls after 6 h exposure. Evidence is presented that the change in the adhesion of osteoclasts from the periosteum to the bone surface, resulting in osteoclast activation, is mediated by OPGL., (Copyright 2000 Academic Press.)

We describe a case of melanoma in situ occurring on the oral mucosa in an adolescent male patient who has dysplastic nevus syndrome. This association has not been previously reported and is of interest both because of the rarity of melanoma involving the oral mucosa, particularly in childhood, and because of the lack of any previous reports of oral mucosal melanoma in association with the dysplastic nevus syndrome.

Motivation: The automatic alignment of rRNA sequences can reproduce manual expert alignments with high, but not perfect, fidelity. We examine the use of empirical methods for the identification of regions of an alignment of a new sequence with an existing large alignment which can confidently be predicted to be correctly aligned., Results: We show how to use a simple jack-knife procedure to derive an estimate of the reliability that is to be expected at each position of a large alignment of eukaryotic rRNA sequences. These reliabilities are then improved using measures that are specific to the input sequence. Regions where the sequence-specific reliability method performs particularly well are identified and seen to correspond with elements in the structure of the rRNA molecules that vary between species in the alignment. We also compare these reliability measures to an algorithmic alignment stability measure., Availability: The software is available free of charge by sending an e-mail message to emmet@chah.ucc.ie., Contact: emmet@chah.ucc.ie

Motivation: Large alignments of ribosomal RNA sequences are maintained at various sites. New sequences are added to these alignments using a combination of manual and automatic methods. We examine the use of profile alignment methods for rRNA alignment and try to optimize the choice of parameters and sequence weights., Results: Using a large alignment of eukaryotic SSU rRNA sequences as a test case, we empirically compared the performance of various sequence weighting schemes over a range of gap penalties. We developed a new weighting scheme which gives most weight to the sequences in the profile that are most similar to the new sequence. We show that it gives the most accurate alignments when combined with a more traditional sequence weighting scheme., Availability: The source code of all software is freely available by anonymous ftp from chah.ucc.ie in the directory /home/ftp/pub/emmet,in the compressed file PRNAA.tar:, Contact: emmet@chah.ucc.ie, des@chah.ucc.ie

We describe a new approach for accurately aligning two homologous RNA sequences when the secondary structure of one of them is known. To do so we developed two software packages, called RAGA and PRAGA, which use a genetic algorithm approach to optimize the alignments. RAGA is mainly an extension of SAGA, an earlier package for multiple protein sequence alignment. In PRAGA several genetic algorithms run in parallel and exchange individual solutions. This method allows us to optimize an objective function that describes the quality of a RNA pairwise alignment, taking into account both primary and secondary structure, including pseudoknots. We report results obtained using PRAGA on nine test cases of pairs of eukaryotic small subunit rRNA sequence (nuclear and mitochondrial).