Whole-genome sequencing in prenatally detected congenital malformations: prospective cohort study in clinical setting

OBJECTIVE

To investigate the diagnostic yield of trio whole-genome sequencing (WGS) in fetuses with various congenital malformations referred to a tertiary center for prenatal diagnosis.

METHODS

In this prospective study, 50 pregnancies with different congenital malformations, negative for trisomies and causative copy-number variants, were analyzed further with fetal-parental trio WGS analysis. Parents were eligible for inclusion if they accepted further investigation following the detection of isolated or multiple malformations on prenatal ultrasound. Cases with isolated increased nuchal translucency, gamete donation or multiple pregnancy were excluded. WGS with the Illumina Inc. 30× polymerase-chain-reaction-free short-read sequencing included analysis of single-nucleotide variants, insertions and deletions, structural variants, short tandem repeats and copy-number identification of SMN1 and SMN2 genes.

RESULTS

A molecular diagnosis was achieved in 13/50 (26%) cases. Causative sequence variants were identified in 12 genes: FGFR3 (n = 2), ACTA1 (n = 1), CDH2 (n = 1), COL1A2 (n = 1), DHCR7 (n = 1), EYA1 (n = 1), FBXO11 (n = 1), FRAS1 (n = 1), L1CAM (n = 1), OFD1 (n = 1), PDHA1 (n = 1) and SOX9 (n = 1). The phenotypes of the cases were divided into different groups, with the following diagnostic yields: skeletal malformation (4/9 (44%)), multisystem malformation (3/7 (43%)), central nervous system malformation (5/15 (33%)) and thoracic malformation (1/10 (10%)). Additionally, two cases carried variants that were considered potentially clinically relevant, even though they were assessed as variants of uncertain significance, according to the guidelines provided by the American College of Medical Genetics and Genomics. Overall, we identified a causative or potentially clinically relevant variant in 15/50 (30%) cases.

CONCLUSIONS

We demonstrate a diagnostic yield of 26% with clinical WGS in prenatally detected congenital malformations. This study emphasizes the benefits that WGS can bring to the diagnosis of fetal structural anomalies. It is important to note that causative chromosomal aberrations were excluded from our cohort before WGS. As chromosomal aberrations are a well-known cause of prenatally detected congenital malformations, future studies using WGS as a primary diagnostic test, including assessment of chromosomal aberrations, may show that the detection rate exceeds the diagnostic yield of this study. WGS can add clinically relevant information, explaining the underlying cause of the fetal anomaly, which will provide information concerning the specific prognosis of the condition, as well as estimate the risk of recurrence. A genetic diagnosis can also provide more reproductive choice for future pregnancies. © 2024 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Rapid PROTAC Discovery Platform: Nanomole-Scale Array Synthesis and Direct Screening of Reaction Mixtures

Precise length, shape, and linker attachment points are all integral components to designing efficacious proteolysis targeting chimeras (PROTACs). Due to the synthetic complexity of these heterobifunctional degraders and the difficulty of computational modeling to aid PROTAC design, the exploration of structure-activity relationships remains mostly empirical, which requires a significant investment of time and resources. To facilitate rapid hit finding, we developed capabilities for PROTAC parallel synthesis and purification by harnessing an array of preformed E3-ligand-linker intermediates. In the next iteration of this approach, we developed a rapid, nanomole-scale PROTAC synthesis methodology using amide coupling that enables direct screening of nonpurified reaction mixtures in cell-based degradation assays, as well as logD and EPSA measurements. This approach greatly expands and accelerates PROTAC SAR exploration (5 days instead of several weeks) as well as avoids laborious and solvent-demanding purification of the reaction mixtures, thus making it an economical and more sustainable methodology for PROTAC hit finding.

Home phototherapy for hyperbilirubinemia in term neonates-an unblinded multicentre randomized controlled trial

The aim of this study was to assess whether home phototherapy was feasible and safe in a cohort of otherwise healthy term-born neonates who fulfilled the criteria for in-hospital phototherapy. This was a randomized controlled trial in which term newborns with a total serum bilirubin of 18-24 mg/dL (300-400 μmol) were randomized to either home phototherapy or conventional in-hospital phototherapy. The primary outcome measurements were safety and efficacy, length of stay and the number of failed treatments. The secondary outcomes were the number of blood samples and weight gain during treatment. One hundred forty-seven patients were recruited, 69 patients randomized to conventional phototherapy and 78 to home phototherapy. The results showed that no patients needed blood exchange and only 4% of the patients allocated to home phototherapy were admitted to the hospital. The duration of phototherapy, length of stay, amount of blood tests and weight change showed no statically significant differences.Conclusion: Home phototherapy could be a safe alternative to inpatient phototherapy for otherwise healthy newborns with hyperbilirubinemia if daily checkups and 24/7 telephone support can be provided. The parents should be informed to contact the hospital immediately if they fail to perform the treatment at home.Trial registration: Clinicaltrials.gov NCT03536078 What is Known: • Phototherapy in the hospital is a safe and effective treatment without major side effects. • Fibre optic equipment has made the choice of home phototherapy possible. What is New: • This is the first randomized controlled trial comparing home phototherapy with hospital phototherapy. • Results indicate that home phototherapy could be considered as a safe and feasible alternative when performed according to instructions given, to hospital treatment for otherwise healthy term newborns.

Retraction of "Targeted Protein Internalization and Degradation by ENDosome TArgeting Chimeras (ENDTACs)"

[This retracts the article DOI: 10.1021/acscentsci.9b00224.].

Targeted Protein Internalization and Degradation by ENDosome TArgeting Chimeras (ENDTACs)

Targeted protein degradation has generated excitement in chemical biology and drug discovery throughout academia and industry. By hijacking the machinery responsible for protein degradation via the ubiquitin proteasome system (UPS), various cellular targets have been selectively degraded. However, since the tools used, often termed PROteolysis TArgeting Chimeras (PROTACs), hijack the intracellular quality control machinery, this technology can only access targets within the cell. Extracellular targets such as growth factors, cytokines, and chemokines bind to cell surface receptors, often initiating aberrant signaling in multiple diseases such as cancer and inflammation. However, efforts to develop small molecule inhibitors for these extracellular target proteins have been challenging. Herein, we developed a proof-of-concept approach to evaluate if extracellular proteins can be internalized and degraded via the receptor-mediated endolysosomal pathway. Using a heterodimeric molecule, termed "ENDosome TArgeting Chimera" (ENDTAC), internalization and degradation of an extracellular recombinant eGFP-HT7 fusion protein was achieved by hijacking the decoy GPCR receptor, CXCR7. This proof-of-concept study suggests that using ENDTACs to co-opt the endosomal-lysosomal degradation pathway, in contrast to PROTACs using the UPS, may provide an avenue for degrading extracellular targets such as cytokines. Overall, the technology described herein provides a novel expansion to the field of targeted protein degradation.

PROteolysis TArgeting Chimeras (PROTACs) - Past, present and future

The majority of currently used therapeutics are small molecule-based and utilize occupancy-driven pharmacology as the mode of action (MOA), in which the protein function is modulated via temporary inhibition. New modalities that operate using alternative MOAs are essential for tapping into the "undruggable" proteome. The PROteolysis Targeting Chimera (PROTAC) technology provides an attractive new approach that utilizes an event-driven MOA. Small molecule-based heterobifunctional PROTACs modulate protein target levels by hijacking the ubiquitin-proteasome system to induce degradation of the target. Here, we address important milestones in the development of the PROTAC technology, as well as emphasize key findings from this previous year and highlight future directions of this promising drug discovery modality.

Flexibility is important for inhibition of the MDM2/p53 protein-protein interaction by cyclic β-hairpins

Protein-protein interactions that have large, flat and featureless binding sites are difficult drug targets. In the development of their modulators conventional drug discovery strategies are often unsuccessful. Gaining a detailed understanding of the binding mode of protein-protein interaction inhibitors is therefore of vast importance for their future pharmaceutical use. The MDM2/p53 protein pair is a highly promising target for cancer treatment. Disruption of the protein complex using p53 α-helix mimetics has been shown to be a successful strategy to control p53 activity. To gain further insight into the binding of inhibitors to MDM2, the flexibility of four cyclic β-hairpins that act as α-helical mimetics and potential MDM2/p53 interaction inhibitors was investigated in relation to their inhibitory activity. MDM2-binding of the mimetics was determined using fluorescence polarization and surface plasmon resonance assays, whereas their conformation and dynamics in solution was described by the combined experimental and computational NAMFIS analysis. Molecular flexibility was shown to be important for the activity of the cyclic β-hairpin based MDM2 inhibitors.

Assessment of Minimum Important Difference and Substantial Clinical Benefit with the Vascular Quality of Life Questionnaire-6 when Evaluating Revascularisation Procedures in Peripheral Arterial Disease

OBJECTIVES

Patient reported outcomes are increasingly used to assess outcomes after peripheral arterial disease (PAD) interventions. VascuQoL-6 (VQ-6) is a PAD specific health-related quality of life (HRQoL) instrument for routine clinical practice and clinical research. This study assessed the minimum important difference for the VQ-6 and determined thresholds for the minimum important difference and substantial clinical benefit following PAD revascularisation.

MATERIALS AND METHODS

This was a population-based observational cohort study. VQ-6 data from the Swedvasc Registry (January 2014 to September 2016) was analysed for revascularised PAD patients. The minimum important difference was determined using a combination of a distribution based and an anchor-based method, while receiver operating characteristic curve analysis (ROC) was used to determine optimal thresholds for a substantial clinical benefit following revascularisation.

RESULTS

A total of 3194 revascularised PAD patients with complete VQ-6 baseline recordings (intermittent claudication (IC) n = 1622 and critical limb ischaemia (CLI) n = 1572) were studied, of which 2996 had complete VQ-6 recordings 30 days and 1092 a year after the vascular intervention. The minimum important difference 1 year after revascularisation for IC patients ranged from 1.7 to 2.2 scale steps, depending on the method of analysis. Among CLI patients, the minimum important difference after 1 year was 1.9 scale steps. ROC analyses demonstrated that the VQ-6 discriminative properties for a substantial clinical benefit was excellent for IC patients (area under curve (AUC) 0.87, sensitivity 0.81, specificity 0.76) and acceptable in CLI (AUC 0.736, sensitivity 0.63, specificity 0.72). An optimal VQ-6 threshold for a substantial clinical benefit was determined at 3.5 scale steps among IC patients and 4.5 in CLI patients.

CONCLUSIONS

The suggested thresholds for minimum important difference and substantial clinical benefit could be used when evaluating VQ-6 outcomes following different interventions in PAD and in the design of clinical trials.

Identification of new TRIP12 variants and detailed clinical evaluation of individuals with non-syndromic intellectual disability with or without autism

The ubiquitin pathway is an enzymatic cascade including activating E1, conjugating E2, and ligating E3 enzymes, which governs protein degradation and sorting. It is crucial for many physiological processes. Compromised function of members of the ubiquitin pathway leads to a wide range of human diseases, such as cancer, neurodegenerative diseases, and neurodevelopmental disorders. Mutations in the thyroid hormone receptor interactor 12 (TRIP12) gene (OMIM 604506), which encodes an E3 ligase in the ubiquitin pathway, have been associated with autism spectrum disorder (ASD). In addition to autistic features, TRIP12 mutation carriers showed intellectual disability (ID). More recently, TRIP12 was postulated as a novel candidate gene for intellectual disability in a meta-analysis of published ID cohorts. However, detailed clinical information characterizing the phenotype of these individuals was not provided. In this study, we present seven novel individuals with private TRIP12 mutations including two splice site mutations, one nonsense mutation, three missense mutations, and one translocation case with a breakpoint in intron 1 of the TRIP12 gene and clinically review four previously published cases. The TRIP12 mutation-positive individuals presented with mild to moderate ID (10/11) or learning disability [intelligence quotient (IQ) 76 in one individual], ASD (8/11) and some of them with unspecific craniofacial dysmorphism and other anomalies. In this study, we provide detailed clinical information of 11 TRIP12 mutation-positive individuals and thereby expand the clinical spectrum of the TRIP12 gene in non-syndromic intellectual disability with or without ASD.

Titanium ions form particles that activate and execute interleukin-1β release from lipopolysaccharide-primed macrophages

BACKGROUND AND OBJECTIVE

Peri-implantitis is a destructive inflammatory process characterized by destruction of the implant-supporting bone. Inflammasomes are large intracellular multiprotein complexes that play a central role in innate immunity by activating the release of proinflammatory cytokines. Although inflammasome activation has previously been linked to periodontal inflammation, there is still no information on a potential association with peri-implantitis. The aim of this study was to examine cytotoxic and proinflammatory effects, including inflammasome activation, of metals used in dental implants, in an in vitro model, as well as from clinical tissue samples.

MATERIAL AND METHODS

Human macrophages were exposed to different metals [titanium (Ti), cobalt, chromium and molybdenum] in a cell-culture assay. Cytotoxicity was determined using the neutral red uptake assay. Cytokine secretion was quantified using an ELISA, and the expression of genes of various inflammasome components was analysed using quantitative PCR. In addition, the concentrations of interleukin-1β (IL-1β) and Ti in mucosal tissue samples taken in the vicinity of dental implants were determined using ELISA and inductively coupled plasma mass spectrometry, respectively.

RESULTS

Ti ions in physiological solutions stimulated inflammasome activation in human macrophages and consequently IL-1β release. This effect was further enhanced by macrophages that have been exposed to lipopolysaccharides. The proinflammatory activation caused by Ti ions disappeared after filtration (0.22 μm), which indicates an effect of particles. Ti ions alone did not stimulate transcription of the inflammasome components. The Ti levels of tissue samples obtained in the vicinity of Ti implants were sufficiently high (≥ 40 μm) to stimulate secretion of IL-1β from human macrophages in vitro.

CONCLUSION

Ti ions form particles that act as secondary stimuli for a proinflammatory reaction.

Design, Synthesis and Evaluation of 2,5-Diketopiperazines as Inhibitors of the MDM2-p53 Interaction

The transcription factor p53 is the main tumour suppressor in cells and many cancer types have p53 mutations resulting in a loss of its function. In tumours that retain wild-type p53 function, p53 activity is down-regulated by MDM2 (human murine double minute 2) via a direct protein-protein interaction. We have designed and synthesised two series of 2,5-diketopiperazines as inhibitors of the MDM2-p53 interaction. The first set was designed to directly mimic the α-helical region of the p53 peptide, containing key residues in the i, i+4 and i+7 positions of a natural α-helix. Conformational analysis indicated that 1,3,6-trisubstituted 2,5-diketopiperazines were able to place substituents in the same spatial orientation as an α-helix template. The key step of the synthesis involved the cyclisation of substituted dipeptides. The other set of tetrasubstituted 2,5-diketopiperazines were designed based on structure-based docking studies and the Ugi multicomponent reaction was used for the synthesis. This latter set comprised the most potent inhibitors which displayed micromolar IC50-values in a biochemical fluorescence polarisation assay.

8-Triazolylpurines: Towards Fluorescent Inhibitors of the MDM2/p53 Interaction

Small molecule nonpeptidic mimics of α-helices are widely recognised as protein-protein interaction (PPIs) inhibitors. Protein-protein interactions mediate virtually all important regulatory pathways in a cell, and the ability to control and modulate PPIs is therefore of great significance to basic biology, where controlled disruption of protein networks is key to understanding network connectivity and function. We have designed and synthesised two series of 2,6,9-substituted 8-triazolylpurines as α-helix mimetics. The first series was designed based on low energy conformations but did not display any biological activity in a biochemical fluorescence polarisation assay targeting MDM2/p53. Although solution NMR conformation studies demonstrated that such molecules could mimic the topography of an α-helix, docking studies indicated that the same compounds were not optimal as inhibitors for the MDM2/p53 interaction. A new series of 8-triazolylpurines was designed based on a combination of docking studies and analysis of recently published inhibitors. The best compound displayed low micromolar inhibitory activity towards MDM2/p53 in a biochemical fluorescence polarisation assay. In order to evaluate the applicability of these compounds as biologically active and intrinsically fluorescent probes, their absorption/emission properties were measured. The compounds display fluorescent properties with quantum yields up to 50%.

Modification of the supramolecular structure of [(thione)IY] (Y = Cl, Br) systems by cooperation of strong halogen bonds and hydrogen bonds

Strong halogen bonds and hydrogen bonds cooperated to control the supramolecular structures of [(thione)IY] (Y = Cl, Br) compounds.

Fabrication and evaluation of SixNy coatings for total joint replacements

Wear particles from the bearing surfaces of joint implants are one of the main limiting factors for total implant longevity. Si(3)N(4) is a potential wear resistant alternative for total joint replacements. In this study, Si(x)N(y)-coatings were deposited on cobalt chromium-discs and Si-wafers by a physical vapour deposition process. The tribological properties, as well as surface appearance, chemical composition, phase composition, structure and hardness of these coatings were analysed. The coatings were found to be amorphous or nanocrystalline, with a hardness and coefficient of friction against Si(3)N(4) similar to that found for bulk Si(3)N(4). The low wear rate of the coatings indicates that they have a potential as bearing surfaces of joint replacements. The adhesion to the substrates remains to be improved.

Vacuum Rabi splitting and strong-coupling dynamics for surface-plasmon polaritons and rhodamine 6G molecules

We report on strong coupling between surface-plasmon polaritons (SPP) and Rhodamine 6G (R6G) molecules, with double vacuum Rabi splitting energies up to 230 and 110 meV. In addition, we demonstrate the emission of all three energy branches of the strongly coupled SPP-exciton hybrid system, revealing features of system dynamics that are not visible in conventional reflectometry. Finally, in analogy to tunable-Q microcavities, we show that the Rabi splitting can be controlled by adjusting the interaction time between waveguided SPPs and R6G deposited on top of the waveguide. The interaction time can be controlled with sub-fs precision by adjusting the length of the R6G area with standard lithography methods.

Anti-HERG activity and the risk of drug-induced arrhythmias and sudden death

AIMS

Drug-induced QTc-prolongation, resulting from inhibition of HERG potassium channels may lead to serious ventricular arrhythmias and sudden death. We studied the quantitative anti-HERG activity of pro-arrhythmic drugs as a risk factor for this outcome in day-to-day practice.

METHODS AND RESULTS

All 284,426 case reports of suspected adverse drug reactions of drugs with known anti-HERG activity received by the International Drug Monitoring Program of the World Health Organization (WHO-UMC) up to the first quarter of 2003, were used to calculate reporting odds ratios (RORs). Cases were defined as reports of cardiac arrest, sudden death, torsade de pointes, ventricular fibrillation, and ventricular tachycardia (n = 5591), and compared with non-cases regarding the anti-HERG activity, defined as the effective therapeutic plasma concentration (ETCPunbound) divided by the HERG IC50 value, of suspected drugs. We identified a significant association of 1.93 (95% CI: 1.89-1.98) between the anti-HERG activity of drugs, measured as log10 (ETCPunbound/IC50), and reporting of serious ventricular arrhythmias and sudden death to the WHO-UMC database.

CONCLUSION

Anti-HERG activity is associated with the risk of reports of serious ventricular arrhythmias and sudden death in the WHO-UMC database. These findings are in support of the value of pre-clinical HERG testing to predict pro-arrhythmic effects of medicines.

Treatment of a Patient with a Nodal Peripheral T-Cell Lymphoma (Angioimmunoblastic T-Cell Lymphoma) with a Human Monoclonal Antibody Against the CD4 Antigen (HuMax-CD4)

A patient with a CD4+ refractory peripheral T-cell lymphoma (PTL), subtype angioimmunoblastic T-cell lymphoma (AILD), was treated with a human monoclonal anti-CD4 antibody (HuMax-CD4) iv once weekly for 10 wk. Early during treatment all palpable enlarged lymph nodes disappeared. A decline of normal CD4+ T-cells in the blood mirrored the treatment effect. Shortly after stopping treatment the patient relapsed with new enlarged lymph nodes. This time no antitumor effect was seen when HuMax-CD4 treatment was reinstituted. No severe side effects were observed during the antibody treatment. This case report is the first describing that HuMax-CD4 has antilymphoma activity in PTL and is an interesting drug to study further in patients with CD4+ PTL.

Rotational isomerism of acetic acid isolated in rare-gas matrices: Effect of medium and isotopic substitution on IR-induced isomerization quantum yield and cis→trans tunneling rate

Rotational isomerization of acetic acid (CH3COOH) is studied in Ar, Kr, and Xe matrices. The light-induced trans-->cis reaction is promoted using resonant excitation of a number of modes in the 3500-7000 cm(-1) region, and the quantum yields for this process are measured for various acetic acid isotopologues and matrix materials. For excitation of acetic acid at energies above the predicted isomerization energy barrier (> or =4400 cm(-1)), the measured quantum yields are in average 2%-3%, and this is one order of magnitude smaller than the corresponding values known for formic acid (HCOOH). This difference is interpreted in terms of the presence of the methyl group in acetic acid, which enhances energy relaxation channels competing with the rotational isomerization. This picture is supported by the observed large effect of deuteration of the methyl group on the photoisomerization quantum yield. The trans-->cis reaction quantum yields are found to be similar for Ar, Kr, and Xe matrices, suggesting similar energy relaxation processes for this molecule in the various matrices. The IR-induced cis-->trans process, studied for acetic acid deuterated in the hydroxyl group, shows reliably larger quantum yields as compared with the trans-->cis process. For pumping of acetic acid at energies below the predicted isomerization barrier, the trans-->cis reaction quantum yields decrease strongly when the photon energy decreases, and tunneling is the most probable mechanism for this process. For the cis-->trans dark reaction, the observed temperature and medium effects indicate the participation of the lattice phonons in the tunneling-induced process.

Association between low Apgar score and neonatal cholestasis

AIM

To investigate the association between low Apgar score and the development of cholestasis.

METHODS

Seventy-seven cholestatic infants, all referred to our tertiary centre and born between 1987 and 1996 were studied. Twenty-eight patients had biliary atresia (BA), 36 had various intrahepatic disorders and for 13 patients the aetiology of the cholestasis was unknown. Data on gestational age, mode of delivery, Apgar score and birthweight for the cholestatic infants and 1,118,270 control subjects born during the same time period were obtained from the Swedish Medical Birth Registry. If the Apgar score of the cholestatic patient was <7 at 1 min and/or <9 at 5 min and/or <9 at 10 min of age the available medical records were reviewed for signs of neonatal distress.

RESULTS

Five cholestatic patients, all of them premature, fulfilled the Apgar criteria. For two of them the low Apgar score and need for immediate resuscitation were explained by major surgical problems. The other three patients, two with biliary atresia (BA) and one with Alagille syndrome, had clinical signs of neonatal distress. The incidence of low Apgar score in BA patients was 7% and in cholestatic patients without known aetiology 0%, neither figure differing significantly from that of the of the control group (2.6%).

CONCLUSION

Low Apgar score is not more common in any of the cholestatic groups than in the general Swedish population of newborns. We suggest that aetiological associations other than low Apgar score need to be considered in infants with cholestasis of unknown cause.

The rate of change of a soil bacterial community after liming as a function of temperature

The response of a bacterial community to liming of a forest humus soil (pH 4.9 increased to pH 7.5) was studied in the laboratory at three temperatures (5, 20, and 30 degrees C). As a comparison an unlimed soil (pH 4.9) and a soil limed in the field 15 years ago (pH around 6) were also included. The bacterial community tolerance of pH was measured using TdR incorporation. The pH of the bacterial suspensions (bacteria directly extracted from soil) was altered to 3.6 and 8.3 using different buffers before measuring TdR incorporation. The logarithmic ratio between TdR incorporation at 8.3 and 3.6 was then used as an indicator of the community pH tolerance. The rate of changes in the community tolerance to pH after liming was fastest for the soil incubated at 30 degrees C, but only minor differences in rate of change could be seen between samples incubated at 5 and 20 degrees C. Changes in phospholipid fatty acid (PLFA) pattern after increasing the pH were most rapid for the bacterial community in the soil incubated at 30 degrees C followed by the soil incubated at 20 degrees C, whereas no changes could be seen in the PLFA pattern of the soil incubated at 5 degrees C, even after 82 days' incubation. Thus, the changes in the PLFA pattern were considerably slower than the changes in bacterial community tolerance to pH measured using TdR incorporation.

Distinct and regulated expression of Notch receptors in hematopoietic lineages and during myeloid differentiation

Hematopoietic development is a delicate balance of cell fate decisions in multipotent cells between self-renewal and differentiation. In multiple developmental systems, the Notch receptors are important factors regulating these processes. Hematopoietic progenitor cells have been shown to express Notch1, and studies with an activated intracellular form has revealed a functional role. To assess the function of other Notch members in hematopoiesis, we investigated the expression pattern of Notch1, Notch2, and Notch3 in hematopoietic lineages at the level of RNA and protein. We demonstrate that Notch1 and Notch2 are expressed in multiple lineages, and that Notch1 in particular appears to be regulated during myeloid differentiation. Notch1 was up-regulated and expressed at high levels in adherent macrophages. Mast cells expressed only low levels of Notch1 mRNA whereas Notch2 mRNA was highly expressed. In addition we could detect Notch3 mRNA and protein in cell lines representing mast cell progenitors. These expression patterns imply that the different Notch genes may have very distinct functions during hematopoiesis, and that Notch3 could be a specific regulator of mast cell development. The finding that Notch1 was up-regulated in the adherent cells developing from a multipotent progenitor cell line suggests that this protein may posses dual functions in hematopoiesis, i.e. at the stage of cell fate decision, and at the maturation stage of monocytes when adhesion to the specific microenvironment is accomplished.

Matrix Isolation and Ab Initio Study of the Hydrogen-Bonded H2O2-CO Complex

The structure, energetics, and infrared spectrum of the H2O2-CO complex have been studied computationally with the use of ab initio calculations and experimentally by FTIR matrix isolation techniques. Computations predict two stable conformations for the H2O2-CO complex, both of which show almost linear hydrogen bonds between the subunits. The carbon-attached HOOH-CO complex is the lower-energy form, and it has an interaction energy of -9.0 kJmol(-1) at the CCSD(T)/6-311++G(3df,3pd)// MP2/6-311++G(3df,3pd) level. The higher-energy form, HOOH-OC, has an interaction energy of 4.7 kJmol(-1) at the same level of theory. Experimentally, only the lower-energy form, HOOH-CO, was observed in Ar, Kr, and Xe matrices, and the hydrogen bonding results in substantial perturbations of the observed vibrational modes of both complex subunits. UV photolysis of the complex species primarily produces a complex between water and carbon dioxide, but minor amounts of HCO and trans-HOCO were found as well.

FT-IR breath test in the diagnosis and control of treatment of methanol intoxications

A portable Fourier transform infrared (FT-IR) multicomponent point-of-care analyzer was tested for the diagnosis of methanol intoxications. Breath analysis with FT-IR was fast and easy, and no sample preparation was needed. The analyzer was adequately sensitive and accurate in detecting and quantitating clinically relevant amounts of ethanol and methanol in the breath of seriously ill patients. FT-IR spectrometry was also suitable for nearly on-line monitoring of the exhaled ethanol and methanol during hemodialysis. The breath analysis results correlated well with blood samples. The FT-IR method used also has a traceable calibration to physical properties of the analyte, and the measured spectra can be saved for later analysis.

Characterization, chromosomal localization, and expression during hematopoietic differentiation of the gene encoding Arl6ip, ADP-ribosylation-like factor-6 interacting protein (ARL6)

Proliferation and differentiation of hematopoietic stem cells and progenitors are regulated by signals from the microenvironment, involving both secreted cytokines and adhesion molecules. The exact mechanisms by which cytokines act on hematopoietic development are still not well understood. To extend the molecular characterization of gene regulation during cytokine-induced hematopoiesis, we applied mRNA differential display to identify genes regulated when multipotent progenitor cells are allowed to differentiate into monocytes and neutrophils. Here we report the isolation and characterization of a gene that is downregulated during myeloid differentiation and encodes a 23-kDa protein with four putative transmembrane segments. The gene, which we named Arl6ip, is identical to a mouse gene recently identified by its physical interaction with ADP-ribosylation-like factor-6 (ARL6), belonging to the Ras superfamily. We add information on its full-length characterization as well as its regulation during hematopoiesis. It is expressed in all hematopoietic cell lineages, but the highest level of expression is found in early myeloid progenitor cells. Preliminary studies by immunofluorescence microscopy revealed that the ARL6IP protein is predominantly localized to intracytoplasmic membranes. This suggests an involvement of the Arl6ip gene in protein transport, membrane trafficking, or cell signaling during hematopoietic maturation.

Vibrational Spectra of cis and trans Oxalyl Fluoride and Their Site-Selective IR-Induced Rotamerization in an Argon Matrix

A cis/trans equilibrium mixture of matrix-isolated oxalyl fluoride was irradiated with a narrowband tunable IR source in the 2nu (CO) spectral region (3680-3710 cm(-1)). Rotamerization of cis into trans and vice versa was achieved (even site selective) by selective IR pumping. The experiments strongly aided a detailed IR analysis of both rotamers. For a complete vibrational analysis, low-temperature Raman measurements were also performed. With the exception of the torsional vibration of cis oxalyl fluoride, all the fundamentals of both rotamers have been observed. Copyright 2000 Academic Press.

The use of low-resolution FT-IR spectrometry for the analysis of alcohols in breath

Fast and reliable diagnostic methods are needed for detection or exclusion of industrial solvents as a cause of intoxication. Analyzing human breath reveals the presence of any volatile substance. A portable Fourier transform infrared (FT-IR) multicomponent point-of-care analyzer was developed for exhaled breath. The analyzer proved to be accurate and precise in laboratory tests for simultaneous measurement of methanol and ethanol in water. Ethanol, in addition to normal contents of breath, was simultaneously analyzed in human experiments, and the results correlated well with blood samples. FT-IR method has a traceable calibration to physical properties of the analyte. The measured spectra can also be saved and analyzed later. Breath analysis with FT-IR is fast and easy, and no preparation of the sample is needed.

Isolation of MYADM, a novel hematopoietic-associated marker gene expressed in multipotent progenitor cells and up-regulated during myeloid differentiation

A large number of hematopoietic cytokines and their receptors as well as transcription factors have been shown to be involved in maturation of blood cells. However, many of the genes important for the differentiation of multipotent stem cells to specific cellular lineages are still unknown. To identify novel genes involved in lineage selection of myeloid cells, we have applied differential display analysis during commitment toward granulocytes and macrophages of an IL-3-dependent multipotent progenitor cell line, FDCP-mix. One regulated cDNA represented a novel gene with restricted expression pattern within the hematopoietic system and was strongly up-regulated when FDCP-mix cells differentiated in GM-CSF, G-CSF, and M-CSF. The expression appears to be differentiation stage-specific in myeloid cells and is absent in B and T lymphocytes. Thus we found expression in normal mouse bone marrow enriched for stem cells and multipotent progenitors (c-kit+Sca-1+Lin- cells). When these cells were induced to differentiate toward myeloid cells, MYADM was up-regulated. In contrast, during conditions known to favor the development of B cell progenitors, the gene was down-regulated. The gene, termed MYADM for myeloid-associated differentiation marker gene, shows 100% identity to expressed sequence tags from early mouse embryonic development as well as from the mouse lung and from activated mouse macrophages. The predicted 32-kDa MYADM protein contains multiple hydrophobic putative transmembrane segments and has several potential consensus sites for phosphorylation. In view of its expression pattern, MYADM could serve as a new marker gene for hematopoietic differentiation. Although the function is unknown, antisense oligonucleotides were able to inhibit colony formation of c-kit+ Lin- bone marrow cells, suggesting an important role for MYADM in myeloid differentiation.

The gene encoding ribosomal protein S19 is mutated in Diamond-Blackfan anaemia

Diamond-Blackfan anaemia (DBA) is a constitutional erythroblastopenia characterized by absent or decreased erythroid precursors. The disease, previously mapped to human chromosome 19q13, is frequently associated with a variety of malformations. To identify the gene involved in DBA, we cloned the chromosome 19q13 breakpoint in a patient with a reciprocal X;19 chromosome translocation. The breakpoint occurred in the gene encoding ribosomal protein S19. Furthermore, we identified mutations in RPS19 in 10 of 40 unrelated DBA patients, including nonsense, frameshift, splice site and missense mutations, as well as two intragenic deletions. These mutations are associated with clinical features that suggest a function for RPS19 in erythropoiesis and embryogenesis.

Withdrawal reactions with selective serotonin re-uptake inhibitors as reported to the WHO system

OBJECTIVE

The present study was performed both to investigate whether there might be a difference between the selective serotonin re-uptake inhibitors, (SSRIs) with regard to the incidence of withdrawal reactions, and to describe the associated symptoms. From the WHO database, therefore, all case reports from the year of introduction for each of the SSRIs, fluoxetine, paroxetine and sertraline, were retrieved. Sales figures were obtained from Intercontinental Medical Statistics International. The reporting rates were calculated as the number of reports per million defined daily doses (DDDs) sold per year.

RESULTS

The reporting rate of withdrawal reactions for paroxetine was found to be higher than that for sertraline and fluoxetine in each of the countries selected for detailed analyses (US, UK and Australia), as well as for all 16 countries combined. Moreover, using the WHO system of organ classification, the ratio of central nervous system to psychiatric withdrawal symptoms was 1.9 and 2.1 for paroxetine and sertraline, respectively, whereas that for fluoxetine was 0.48, indicating a possible qualitative difference between the SSRIs with respect to the nature of the withdrawal syndrome.