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We describe two males with intellectual disability ID and facial dysmorphism, both of whom have nonmosaic Y chromosome rearrangements resulting in deletions of large portions of the Y chromosome. Patient A, with ID, mild dysmorphism, speech delay, Duane anomaly of the eye, hypermetropia and conductive hearing loss, had two structurally rearranged Y chromosomes resulting in both p and q arm deletions in addition to a Yp duplication. Patient B, also with speech and language delay, developmental delay and short stature, had an interstitial deletion of Yq11.21–11.23. ArrayCGH excluded the presence of additional submicroscopic rearrangements at the 1 Mb resolution level. A review of males with Y chromosome rearrangements and ID was performed. Our study provides a more detailed molecular cytogenetic assessment of Y rearrangements in individuals with ID than has been previously possible, and facilitates assessment and comparison of other individuals with a Y chromosome rearrangement. © 2009 WileyLiss, Inc.

The 5-hydroxytryptamine-3 (5-HT3) receptor, a ligand-gated ion channel, is known to be involved in gut motility and peristalsis, the mediation of pain and psychiatric diseases. 5-HT3receptor antagonists are effectively used to treat chemotherapy-induced emesis and irritable bowel syndrome. We have characterized the impact of four naturally occurring variants in the HTR3Bgene leading to amino acid exchanges within the respective subunit of heteromeric 5-HT3ABreceptors on a functional and expressional level.

Knowledge about the extent of total variation experienced between samples from different individuals is of great importance for the design of not only proteomics but every clinical study. This variation defines the smallest statistically significant detectable signal difference when comparing two groups of individuals. We isolated platelets from 20 healthy human volunteers aged 56–100 years because this age group is most commonly encountered in the clinics. We determined the technical and total variation experienced in a proteome analysis using two-dimensional DIGE with IPGs in the pI ranges 4–7 and 6–9. Only spots that were reproducibly detectable in at least 90% of all gels (n = 908) were included in the study. All spots had a similar technical variation with a median coefficient of variation (cv) of about 7%. In contrast, spots showed a more diverse total variation between individuals with a surprisingly low median cv of only 18%. Because most known biomarkers show an effect size in a 1–2-fold range of their cv, any future clinical proteomics study with platelets will require an analytical method that is able to detect such small quantitative differences. In addition, we calculated the minimal number of samples (sample size) needed to detect given protein expression differences with statistical significance.

Within the family of serotonin receptors, the 5-hydroxytryptamine-3 (5-HT3) receptor is the only ligand-gated ion channel. It is composed of five subunits, of which the 5-HT3Aand 5-HT3Bsubunits are best characterized. Several studies, however, have reported on the functional diversity of native 5-HT3receptors, which cannot solely be explained on the basis of the 5-HT3Aand 5-HT3Bsubunits. After our discovery of further putative 5-HT3serotonin receptor-encoding genes, HTR3C, HTR3D, and HTR3E, we investigated whether these novel candidates and the isoform 5-HT3Eaare able to form functional 5-HT3receptor complexes. Using immunofluorescence and immunoprecipitation studies of heterologously expressed proteins, we found that each of the respective candidates coassembles with 5-HT3A. To investigate whether the novel subunits modulate 5-HT3receptor function, we performed radioligand-binding assays and calcium-influx studies in human embryonic kidney 293 cells. Our experiments revealed that the 5-HT3C,5-HT3D, 5-HT3E, and 5-HT3Easubunits alone cannot form functional receptors. Coexpression with 5-HT3A, however, results in the formation of functional heteromeric complexes with different serotonin efficacies. Potencies of two agonists and antagonists were nearly identical with respect to homomeric 5-HT3Aand heteromeric complexes. However, 5-HT showed increased efficacy with respect to 5-HT3A/Dand 5-HT3A/Ereceptors, which is consistent with the increased surface expression compared with 5-HT3Areceptors. In contrast, 5-HT3A/Cand 5-HT3A/Eareceptors exhibited decreased 5-HT efficacy. These data show for the first time that the novel 5-HT3subunits are able to form heteromeric 5-HT3receptors, which exhibit quantitatively different functional properties compared with homomeric 5-HT3Areceptors.

Phillips: Incyte: Consultancy, Other: travel expenses; Seattle Genetics: Consultancy; BMS: Consultancy; Bayer: Consultancy, Research Funding; Pharmacyclics: Consultancy; Abbvie: Consultancy, Research Funding; AstraZeneca: Consultancy; Beigene: Consultancy; Karyopharm: Consultancy; Cardinal Health: Consultancy. Corradini:KiowaKirin: Consultancy, Honoraria; Incyte: Consultancy; Daiichi Sankyo: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; F. Hoffman-La Roche Ltd: Consultancy, Honoraria; Amgen: Consultancy, Honoraria, Other: Travel and accommodations paid by for; Novartis: Consultancy, Honoraria, Other: Travel and accommodations paid by for; Takeda: Consultancy, Honoraria, Other; BMS: Other; Kite: Consultancy, Honoraria; Servier: Consultancy, Honoraria; AbbVie: Consultancy, Honoraria, Other: Travel and accommodations paid by for; Gilead: Consultancy, Honoraria, Other: Travel and accommodations paid by for; Sanofi: Consultancy, Honoraria; Celgene: Consultancy, Honoraria, Other: Travel and accommodations paid by for. Gurion:Medison: Consultancy; Gilead Sciences: Consultancy; Takeda Pharmaceuticals: Consultancy; JC Health CARE: Honoraria; Roche: Honoraria. Avigdor:Takeda, Gilead, Pfizer: Consultancy, Honoraria; Janssen, BMS: Research Funding. Jurczak:MorphoSys: Research Funding; European Medicines Agency,: Consultancy; Sandoz-Novartis: Consultancy; Takeda: Research Funding; Roche: Research Funding; Pharmacyclics: Research Funding; Merck: Research Funding; MEI Pharma: Research Funding; Janssen China R&D: Consultancy, Research Funding; BeiGene: Consultancy, Research Funding; Bayer: Research Funding; Afimed: Research Funding; Celgene: Research Funding; Epizyme: Consultancy; Gilead Sciences: Research Funding; Nordic Nanovector: Research Funding; Servier: Research Funding; Maria Sklodowska-Curie National Research Institute of Oncology, Krakow, Poland: Current Employment; TG Therapeutics, Inc.: Research Funding; Acerta: Consultancy, Research Funding; Jagiellonian University, Krakow, Poland: Ended employment in the past 24 months; AstraZeneca: Consultancy. 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The article discusses the impacts of the Covid-19 pandemic on the Germany's European Union Council Presidency.

Transuterine migration is the passage of fertilised ova from one uterine horn into the other. The phenomenon has been described for animals of different species with a bicornuate type of uterus. Whether or not it occurs in rodents is questionable, but could have an impact on the way embryo transfers are carried out, i.e. unilaterally or bilaterally. The aim of this study was to examine the occurrence of transuterine migrations in nulliparous and multiparous mice after unilateral embryo transfer. Sixteen two-cell embryos were transferred into either the left or the right oviduct of mice with different genetic origin. With the exception of one reabsorption site in the opposite uterine horn, we never found evidence for the occurrence of transuterine migration. This is also true for embryo transfers carried out after parturition of the surrogate mother. Even the successful development of up to 13 embryos in one uterine horn did not result in transmigration but may be the reason for the widespread assumption that transuterine migration occurs after unilateral embryo transfers. The separation of the uterine body and the prevaginal portion of the uterine cervix into two canals by a septum seems to be the main reason for the absence of successful transuterine migration in mice.

The neurotransmitter serotonin (5‐hydroxytryptamine, 5‐HT) mediates a multitude of central nervous functions by activating 5‐HT receptor subtypes. A dysfunction of serotonergic neurotransmission is considered to play a major role in the pathophysiology of complex neuropsychiatric disorders. In our study, a mutation screen of the serotonin receptor gene HTR3B was carried out to explore a putative contribution to the etiology of bipolar affective disorder (BPAD) and schizophrenia (SZ). Screening of 49 patients suffering from BPAD, 78 patients with SZ and 62 control individuals revealed eleven sequence variations including a 3 bp deletion within the 5′UTR (5′ untranslated region), four exonic and five intronic SNPs as well as a point mutation in the 3′UTR of HTR3B. Four of these sequence variations have not been described previously. Statistical computation rated most variants as probably non‐disease related polymorphisms. However, IVS6 + 31C > T, IVS6 + 40C > A, and 1386T > C were solely detected in bipolar affective patients and in none of the controls. Interestingly, we observed a significant underrepresentation of the 3 bp deletion −100_−102delAAG in an extended sample of 162 bipolar affected patients compared to controls (allele‐wise: 8% vs. 15%, P = 0.006, OR = 0.49, 95% CI: 0.3–0.82; genotype‐wise: 15,5% vs. 29,0%, P = 0.005, OR = 0.45, 95% CI: 0.26–0.77). We suggest that this deletion may influence translational efficiency, thereby possibly affecting the development of bipolar affective disease. © 2004 Wiley‐Liss, Inc.

Conductive hearing loss was detected in a boy with a previous diagnosis of dyschondrosteosis. Dyschondrosteosis is a rare inherited condition characterized by mesomelic dwarfism and Madelung's deformity. The syndrome can be caused by mutations in the SHOX gene, and in that case, the pattern of inheritance is pseudoautosomal dominant. Indeed, SHOX mutation analysis in our patient revealed a deletion. The combination of dyschondrosteosis and conductive hearing loss has been reported in 2 previous cases. In our patient, exploratory tympanotomy revealed ankylosis of the stapes and a malformed incus. A substantial gain in hearing threshold was obtained by a stapedectomy in combination with a malleovestibulopexy.

The human pseudoautosomal region 1 (PAR1) is essential for meiotic pairing and recombination, and its deletion causes male sterility. Comparative studies of human and mouse pseudoautosomal genes are valuable in charting the evolution of this interesting region, but have been limited by the paucity of genes conserved between the two species. We have cloned a novel human PAR1 gene, DHRSXY, encoding an oxidoreductase of the short-chain dehydrogenase/reductase family, and isolated a mouse ortholog Dhrsxy. We also searched for mouse homologs of recently reported PGPL and TRAMP genes that flank it within PAR1. We recovered a highly conserved mouse ortholog of PGPL by cross-hybridization, but found no mouse homolog of TRAMP. Like Csf2ra and Il3ra, both mouse homologs are autosomal; Pgpl on chromosome 5, and Dhrsxy subtelomeric on chromosome 4. TRAMP, like the human genes within or near PAR1, is probably very divergent or absent in the mouse genome. We interpret the rapid divergence and loss of pseudoautosomal genes in terms of a model of selection for the concentration of repetitive recombinogenic sequences that predispose to high recombination and translocation.

We report on a three-month-old boy with a 46,XY,der(Y)t(Y;7)(p11.32;p15.3) karyotype and growth deficiency, postnatal microcephaly with large fontanels, wide sagittal and metopic sutures, hypertelorism, choanal stenosis, micrognathia, bilateral cryptorchidism, hypospadias, abnormal fingers and toes, and severe developmental delay. FISH studies showed partial trisomy 7p resulting from a de novo unbalanced translocation. The application of molecular probes from the TWIST gene region (7p15.3–p21.1) and probes from the pseudoautosomal region (PAR) demonstrated that the 7p15.3-pter fragment was translocated onto Yp with the breakpoint within ~20 kb from the Yp telomere. We discuss the possible role of the TWIST gene in abnormal skull development and suggest that trisomy 7p cases with delayed closure of fontanels can be a result of TWIST gene dosage effect. © 2001 Wiley-Liss, Inc.

Serotonin receptor type 3 is a ligand-gated ion channel implicated in behavioural disorders. Our objective was to identify nucleotide variants in a specific portion of the 5′ region of the serotonin receptor gene (HTR3A) containing upstream open reading frames (uORFs) and to investigate their effect on bipolar disease. Mutations in uORFs have been recently shown to cause disease by changing expression on the translational level. We identified one polymorphism, C195T, and one missense mutation, C178T (Pro16Ser) within an upstream open reading frame. No significant association was found between the C195T polymorphism and bipolar affective disorder. A significant association was, however, found between the variant C178T in 156 patients with bipolar disorder compared to 156 healthy controls (P0.00016). To investigate the relevance of this variant on gene expression, luciferase reporter constructs containing the C178T (Pro16Ser) allele were established and compared to the C178T plus C195T and wild-type alleles. Reporter constructs containing the C178T (Pro16Ser) allele drove 245 and 138 expression compared to the wild-type allele. These findings show that the C178T(Pro16Ser) variant in HTR3Amay represent a functional variant and affect the susceptibility to bipolar disorder.

We report the results of detailed molecular-cytogenetic studies of two isodicentric Y [idic(Y)] chromosomes identified in patients with complex mosaic karyotypes. We used fluorescence in situ hybridization (FISH) and polymerase chain reaction (PCR) to determine the structure and genetic content of the abnormal chromosomes. In the first patient, classical cytogenetics and FISH analysis with Y chromosome-specific probes showed in peripheral blood lymphocytes a karyotype with 4 cell lines: 45,X[128]/46,X,+idic(Y)(p11.32)[65]/47,XY,+idic(Y)(p11.32)[2]/47,X,+2idic(Y)(p11.32)[1]. No Y chromosome material was found in the removed gonads. For precise characterization of the Yp breakpoint, FISH and fiberFISH analysis, using a telomeric probe and a panel of cosmid probes from the pseudoautosomal region PAR1, was performed. The results showed that the breakpoint maps ~1,000 Kb from Ypter. The second idic(Y) chromosome was found in a boy with mild mental retardation, craniofacial anomalies, and the karyotype in lymphocytes 47,X,+idic(Y)(q11.23),+i(Y)(p10)[77]/46,X,+i(Y)(p10)[23]. To our knowledge, such an association has not been previously described. FISH and PCR analysis indicated the presence of at least two copies of the SRY gene in all analyzed cells. Using 17 PCR primers, the Yq breakpoint was shown to map between sY123 (DYS214) and sY121 (DYS212) loci in interval 5O in AZFb region. Possible mechanisms of formation of abnormal Y chromosomes and karyotype-phenotype correlations are discussed. © 2001 Wiley-Liss, Inc.

Serotonin receptor genes have always been considered excellent candidate genes in the aetiology of neurogenetic diseases. In this study, we assessed sequence variations of the HTR3Agene. For this purpose, we established exon-specific primers and analysed DNA samples from 165 unrelated individuals including 70 schizophrenic patients, 48 patients with bipolar affective disorder and 47 healthy control persons using polymerase chain reaction/single-strand conformational polymorphism analysis. We discovered six sequence variants, five of which represent polymorphisms. These polymorphisms could not be associated with schizophrenia and bipolar affective disorder (P0.055–1). We also detected a missense mutation in exon 9 in a schizophrenic patient at a conserved position (Pro391Arg). To determine the incidence of this substitution an extended set of 358 schizophrenic patients and 155 control individuals was investigated. The Pro391Arg mutation was not detected in these schizophrenic patients and controls screened. However, a second missense mutation (Arg344His) was detected in one schizophrenic patient, but not in any of the controls. These results suggest that the observed mutations in HTR3Aare rare and therefore do not play a major role in the aetiology of the disorder. Further studies are needed to support the hypothesis that HTR3Amay contribute to the schizophrenia in these patients.

At least 1 in 1000 males lacks part of the long arm of the Y chromosome. This chromosomal aberration is often associated with short stature and infertility. Deletion mapping and genotype-phenotype analysis have previously defined two non-overlapping critical regions for growth controlling gene(s), GCY(s), on the euchromatic portion of the Y chromosome long arm. These initial mapping assignments were based on the analysis of patients carrying a pure 46,XYq- karyotype as defined by classical cytogenetic karyotyping. Four genes have been assigned to the distal one of the two critical regions. To determine whether one or both of these two critical regions harbours GCY and whether one of the four genes assigned to the distal region is involved in determination of stature, nine adult patients with Yq chromosomal abnormalities were studied in detail. By PCR and FISH analysis, we showed that all patients with a previously defined pure 46,XYq- karyotype are actually mosaics with cells containing an idic(Y) or ring(Y) chromosome in association with 45,X0 cells. This leads us to conclude that (1) FISH is an absolute prerequisite for the correct identification of Y chromosomal rearrangements and (2) only patients with interstitial Y deletions are reliable predictors for the physical location of stature gene(s) on Yq. Our molecular analyses of chromosomes from patients with interstitial Yq deletions finally establishes the proximal interval between markers DYZ3 and DYS11 as the only GCY critical interval. No functional gene has so far been identified in this region adjacent to the centromere.

The system under study is a single item, two-echelon production-inventory system consisting of a capacitated production facility, a central warehouse, and M regional distribution centers that satisfy stochastic demand. Our objective is to determine a system base-stock level which minimizes the long run average system cost per period. Central to the approach are (1) an inventory allocation model and associated convex cost function designed to allocate a given amount of system inventory across locations, and (2) a characterization of the amount of available system inventory using the inventory shortfall random variable. An exact model must consider the possibility that inventories may be imbalanced in a given period. By assuming inventory imbalances cannot occur, we develop an approximation model from which we obtain a lower bound on the per period expected cost. Through an extensive simulation study, we analyze the quality of our approximation, which on average performed within 0.50% of the lower bound. © 2000 John Wiley & Sons, Inc. Naval Research Logistics 47: 377–398, 2000

We report on a 9-year-old boy with a rare rearranged Y chromosome and borderline short stature (−2.0 SD). Standard metaphase chromosome analysis indicated a 46,X,i(Y)(q10) karyotype, but high resolution G-banding showed an asymmetric band pattern for the rearranged Y chromosome. FISH and DNA studies for a total of 15 different Y chromosomal loci or regions showed that the rearranged Y chromosome was accompanied by: 1) a partial deletion of the short arm pseudoautosomal region (PAR1) involving SHOX, with the breakpoint distal to DXYS85; and 2) a partial duplication of Yq, with the breakpoint proximal to DAZ. The karyotype was determined as 46,X,?i(Y)(q10).ish der(Y)(Yqter→ Yp11.3::Yq11.2→Yqter)(DAZ++,DYZ3+,SRY+, SHOX−). The X chromosome and the autosomes were normal. The results suggest that haploinsufficiency of SHOX is primarily responsible for the borderline short stature, and that the deletion of the PAR1 may result in spermatogenic failure due to defective X-Y pairing and recombination in the PAR1. Am. J. Med. Genet. 92:256–259, 2000. © 2000 Wiley-Liss, Inc.

Three distinct classes of epitopes on human CD164 have been identified. Two of these, recognized by the monoclonal antibodies 105A5 and 103B2/9E10, are the CD164 class I and class II functionally defined epitopes, which cooperate to regulate adhesion and proliferation of CD34+ cell subsets. In this article, we demonstrate that these 2 CD164 epitopes are expressed on CD34+ cells throughout ontogeny, in particular on CD34+ cell clusters associated with the ventral floor of the dorsal aorta in the developing embryo and on CD34+ hematopoietic precursor cells in fetal liver, cord blood, and adult bone marrow. While higher levels of expression of these CD164 epitopes occur on the more primitive AC133hiCD34hiCD38lo/- cell population, they also occur on most cord blood Lin-CD34lo/-CD38lo/- cells, which are potential precursors for the AC133hiCD34hiCD38lo/- subset. In direct contrast to these common patterns of expression on hematopoietic precursor cells, notable differences in expression of the CD164 epitopes were observed in postnatal lymphoid and nonhematopoietic tissues, with the class I and class II CD164 epitopes generally exhibiting differential and often reciprocal cellular distribution patterns. This is particularly striking in the colon, where infiltrating lymphoid cells are CD164 class I–positive but class II–negative, while epithelia are weakly CD164 class II–positive. Similarly, in certain lymphoid tissues, high endothelial venules and basal and subcapsular epithelia are CD164 class II–positive, while lymphoid cells are CD164 class I–positive. It therefore seems highly likely that these CD164 class I and II epitopes will mediate reciprocal homing functions in these tissue types.

Structural abnormalities of chromosome 18p mainly consist of isochromosomes of the short arm, which result in tetrasomy 18p. Trisomy 18p is much rarer, and less well characterized. We report on a 12-year-old girl with minor facial anomalies, delayed development, abnormal hands, atopic dermatitis, and hearing loss. She was mosaic for two abnormal cell lines in peripheral blood. In 90% of cells, a dicentric chromosome with duplication of the whole short arm of chromosome 18 resulted in trisomy 18p; 10% of cells had monosomy 18p, arising from a t(14;18)(p11;q11). FISH mapping, with multiple region specific and locus specific probes from the short and long arm of chromosome 18, showed that the structure of the dicentric chromosome 18 was 18pter→18q23::18q11→18pter. DNA polymorphisms for chromosome 18 showed that the abnormalities of chromosome 18 were paternal in origin. Combining all results, we could link the trisomy 18p and monosomy 18p to a common origin via a complex series of events in an early mitosis. Am. J. Med. Genet. 92:101–106, 2000. © 2000 Wiley-Liss, Inc.

Members of the cAMP-dependent second-messenger pathway have been described as regulators of cellular growth and differentiation and were consequently implicated in a variety of embryogenic processes including brain development. Moreover, recent data suggest an indispensable role for cAMP-dependent protein kinases (PKAs) in neuronal differentiation and synaptic plasticity. Using a degenerate primer-based approach, we have identified a novel murine gene closely related to the human cAMP-dependent protein kinase PRKX on Xp22.3. This gene (Pkare) was mapped to the region near the centromere of the murine X chromosome and is expressed in a variety of adult organs including kidney, liver, spleen, testis, ovary, lung, heart, and brain. Antisense in situhybridization on staged mouse embryos revealed a highly distinctive expression pattern during neuronal development, with elevated Pkare expression observed only in differentiating neurons within the first ganglion, the dorsal root ganglia, and the mantle layer of the telencephalon. Based on the close relationship with the catalytic PKA subunits and its distinct expression in differentiating neuronal cells, Pkare might represent a novel component of the cAMP-regulated pathways involved in brain development and function.

In systemic therapy trials, a decreasing neutrophil-to-lymphocyte ratio (NLR) after treatment for metastatic renal cell carcinoma (RCC) has been associated with improved oncologic outcomes. Paradoxically, for patients with localized RCC treated with upfront surgery the opposite effect has been reported. We thus aimed to evaluate NLR dynamics on localized RCC recurrence.

Background:Marginal zone lymphoma (MZL) is the third most common lymphoma in Western countries, accounting for 8-12% of non-Hodgkin lymphoma (Delinger NM. Cancer Manag Res.2018;10:315-24). MZL is categorized into nodal, extranodal, and splenic subtypes. While the relative 5-year survival rate for patients (pts) with MZL is 84.4% (Olszewski AJ, Castillo JJ. Cancer.2013;119:629-38), pts often experience relapse or refractory (R/R) disease. Parsaclisib is a potent, highly selective, next-generation inhibitor of phosphatidylinositol 3-kinase (PI3K)δ. Here we report results of the primary analysis of the cohort of Bruton's tyrosine kinase (BTK) inhibitor (BTKi)-naive pts with R/R MZL treated with parsaclisib monotherapy in the open-label, phase 2 study CITADEL-204 (NCT03144674, EudraCT 2017-000970-12).

Introduction:Exposure to ambient nitrogen dioxide (NO2) is associated with adverse respiratory and cardiovascular outcomes. Supplementation of omega-3 polyunsaturated fatty acids (PUFA) has shown health benefits against exposure to air pollution.Hypothesis:Dietary omega-3 PUFA intake offers cardiovascular and respiratory benefits against short-term exposure to ambient NO2in healthy adults.Methods:Sixty-two healthy participants were enrolled into low or high omega-3 groups based on their habitual dietary omega-3 PUFA intake. Each participant was repeatedly assessed for blood lipids, markers of coagulation and fibrinolysis, vascular function, heart rate variability (HRV), and lung function up to five times separated by at least 7 days between October 2016 and September 2019. Daily ambient NO2concentrations were obtained from nearby air quality monitoring stations. The associations between NO2concentrations and the measured biomarkers were evaluated using the linear mixed-effects models stratified by the omega-3 intake levels.Results:In the high omega-3 group, an IQR increase in NO2concentrations was associated with reductions in total cholesterol at lag2 [-2.6% (-4.4, -0.9)], LDL at lag2 [-3.1% (-5.5, -0.7)], and HDL at lag1 [-2.4% (-4.4, -0.3)] and lag2 [-2.0% (-3.8, -0.1)]; increases in flow-mediated dilatation of brachial artery at lag1[5.7% (0.1, 11.2)] and lag2 [5.7% (0.8, 10.6)]; decreases in plasma levels of endothelin-1at lag3 [-25.6% (-50.0, -1.2)] and lag4 [-22.9% (-45.9, -0.01)]; decreased high frequency (HFn) of HRV [-7.2% (-13.6, -0.8)] and increased LF/HF ratio [13.4% (0.2, 28.3)] at lag3; as well as increased lung function. In the low omega-3 group, blood lipids, vascular function biomarkers and lung function were not significantly associated with NO2exposure. However, NO2exposure was associated with elevations in coagulation markers (von Willebrand Factor and D-dimer) and a decrease in very-low frequency of HRV at lag0 in the low omega-3 group.Conclusions:The results imply that high dietary omega-3 PUFA intake may offer benefits to cardiovascular and respiratory health in response to exposure to low-level ambient NO2in healthy adults. THIS ABSTRACT OF A PROPOSED PRESENTATION DOES NOT NECESSARILY REFLECT EPA POLICY.

Signal-regulatory proteins (SIRPs) comprise a novel transmembrane glycoprotein family involved in the negative regulation of receptor tyrosine kinase-coupled signaling pathways. To analyze the expression and function of SIRPs, we prepared soluble recombinant fusion proteins of the extracellular regions of SIRP?1 and SIRP?2, as well as a variety of monoclonal antibodies (MoAbs) against these domains. The antibodies reacted predominantly with monocytes, granulocytes, dendritic cells, and their precursors, as well as with bone marrow CD34+, AC133+, CD90+hematopoietic stem/progenitor cells. In contrast, SIRP expression was absent or significantly reduced on the majority of myeloid blasts from patients with acute myeloid leukemia (AML) or chronic myeloid leukemia (CML). Functional studies showed that the extracellular domains of SIRP?1 and SIRP?2 support adhesion of a number of primary hematopoietic cells and cell lines. This interaction could be blocked by 4 of 7 SIRP?1-reactive MoAbs. In addition, SIRP?1 and SIRP?2 competed for the same cell binding site, suggesting a common widely expressed SIRP ligand. In an approach to identify this molecule, MoAbs were generated against the SIRP-binding cell line CCRF-CEM, and MoAb CC2C6 was selected because of its capacity to inhibit cell binding to SIRP?1. Further analysis showed that this antibody recognized CD47, a ubiquitously expressed plasma membrane protein previously implicated in integrin function, host defense action, and neutrophil migration. In this study, we identify CD47 as the extracellular ligand for human SIRP and show that these two counterreceptors are involved in cellular adhesion.

Deletion in chromosome bands 11q22-q23 is one of the most common chromosome aberrations in B-cell chronic lymphocytic leukemia (B-CLL). It is associated with extensive lymph node involvement and poor survival. The minimal consensus deletion comprises a segment, which contains the ATM gene presenting an interesting candidate gene, as mutations in ATM predispose A-T patients to lymphoid malignancies. To investigate a potential pathogenic role of ATM in B-cell tumorigenesis, we performed mutation analysis of ATM in 29 malignant lymphomas of B-cell origin (B-CLL = 27; mantle cell lymphoma, [MCL] = 2). Twenty-three of these carried an 11q22-q23 deletion. In five B-CLLs and one MCL with deletion of one ATMallele, a point mutation in the remaining allele was detected, which resulted in aberrant transcript splicing, alteration, or truncation of the protein. In addition, mutation analysis identified point mutations in three cases without 11q deletion: two B-CLLs with one altered allele and one MCL with both alleles mutated. In four cases analyzed, theATM alterations were not present in the germ line indicating a somatic origin of the mutations. Our study demonstrates somatic disruption of both alleles of the ATM gene by deletion or point mutation and thus its pathogenic role in sporadic B-cell lineage tumors.

The position of deletion breakpoints in a series of four AZFa male infertility patients has been refined using new markers derived from BAC clone DNA sequence covering the AZFa male infertility interval. The proximal half of the AZFa interval is occupied by pseudogene sequences with homology to Xp22. The distal half contains an anonymous expressed sequence tag (named AZFaT1) found transcribed in brain, testis, and skeletal muscle and the DFFRY and DBY genes. All the patients have AZFaT1 and DFFRY deleted in their entirety and three patients additionally have DBY deleted. The three patients with AZFaT1, DFFRY, and DBY deleted show a severe Sertoli cell only syndrome type I phenotype, whereas the patient that has retained DBY shows a milder oligozoospermic phenotype. The expression of DBY in a cell line from this latter patient is unaltered; this shows that it is the loss of genes lying within the deletion that is responsible for the observed oligozoospermia. RT-PCR analysis of mouse testis RNA from normal and XXSxr^a mice (devoid of germ cells) has shown that Dby is expressed primarily in somatic cells and that the level of expression is unaltered during germ cell differentiation. This contrasts with Dffry where no transcripts are detectable in XXSxr^a mouse testis and expression occurs specifically in testis mRNA in a germ cell dependent fashion.

We report on a mother and her 5-year old son, both with a terminal deletion of the short arm of the X chromosome. By molecular genetic analysis the breakpoint was located distal to steroid sulfatase gene. The boy manifested, due to nullisomy of this region, short stature (SHOX), chondrodysplasia punctata (ARSE), and mental retardation (putative mental retardation gene MRX 49). Short stature is present in mother and son, but both also had bilateral Madelung deformity, a key finding in the Léri-Weill syndrome.We discuss the phenotype in relationship to hitherto published cases with chromosomal aberrations and contiguous gene syndromes of Xp22.3. Am. J. Med. Genet. 83:367–371, 1999. © 1999 Wiley-Liss, Inc.

The three-dimensional positioning of the X-chromosomal adenine nucleotide translocase genes, ANT2 and ANT3, were compared in the active and inactive X chromosome territories (Xa and Xi) of female human amniotic fluid cell nuclei. ANT2 is located in Xq24-q25 and is transcriptionally active on Xa, but inactive on Xi. ANT3 is located in the pseudoautosomal region Xp22.3 and escapes X-inactivation. Three-color fluorescence in situhybridization, confocal laser scanning microscopy, and three-dimensional image analysis revealed that transcriptionally active ANT2 and ANT3 genes were positioned more peripheral within their chromosome territory than the inactive ANT2 gene. The position of the latter was significantly more interior in the Xi territory. Although the volumes of both X territories were similar, 3D distances between ANT2 and ANT3 were significantly smaller in Xi compared to Xa territories reflecting different territory shapes. Our data show a correlation between 3D positioning and transcriptional activity of these X-specific genes.

Translocation of nuclear-encoded mitochondrial preproteins is mediated by translocases in the outer and inner membranes. In the yeast Saccharomyces cerevisiae, translocation of preproteins into the matrix requires the membrane proteins Tim23, Tim17 and Tim44, which drive translocation in cooperation with mtHsp70 and its co-chaperone Mge1p. We have cloned and functionally analyzed the human homologues of Tim17, Tim23 and Tim44. In contrast to yeast, two TIM17 genes were found to be expressed in humans. TIM44, TIM23 and TIM17a genes were mapped to chromosomes 19p13.2-p13.3, 10q11.21-q11.23 and 1q32. The TIM17b gene mapped to Xp11.23, near the fusion point where an autosomal region was proposed to have been added to the “ancient” part of the X chromosome about 80–130 MY ago. The primary sequences of the two proteins, hTim17a and hTim17b, are essentially identical, significant differences being restricted to their C termini. They are ubiquitously expressed in fetal and adult tissues, and both show expression levels comparable to that of hTim23. Biochemical characterization of the human Tim components revealed that hTim44 is localized in the matrix and, in contrast to yeast, only loosely associated with the inner membrane. hTim23 is organized into two distinct complexes in the inner membrane, one containing hTim17a and one containing hTim17b. Both TIM complexes display a native molecular mass of 110 kDa. We suggest that the structural organization of TIM23·17 preprotein translocases is conserved from low to high eukaryotes.

Fossil fuels are still the most important source for supplying the world's energy and heating needs. The growing demands of more stringent pollution control regulations make it necessary to develop new flue gas cleaning processes. Up to now there is no known process that allows the dry separation of hydrogen chloride from flue gases with ready adsorbent regeneration. The well known BF‐Uhde process cannot be applied to flue gases containing hydrogen chloride. Our aim was to develop a process for dry separation of hydrogen chloride from flue gases that can be used in combination with the BF‐Uhde process. The new process is based on a gas‐solid reaction between active magnesia and hydrogen chloride at temperatures of about 120 °C. The new process performed well in experiments conducted under industrial conditions. The adsorbent can be regenerated at temperatures of about 450 °C. Hydrogen fluoride is the only known flue gas component that interferes with the regeneration capability of the adsorbent.

We have determined the localization of c‐myc and the immunoglobulin kappa light chain genes on the 8q+/2p‐ chromosomes of the three Burkitt lymphoma lines BL21, LY66 and LY91 with t(2;8) translocation by in situ hybridization. BL21 is characterized by a complex translocation in which a piece of chromosome 9 appears to be located between the fragments of chromosome 8 and 2 on the 8q+ chromosome. Our data indicate that in all three cell lines the c‐myc gene is located on the 8q+ chromosome proximal to the breakpoint in band 8q24. In all cell lines examined the cluster of kappa variable genes has remained on the 2p‐ chromosome. In LY91 cells the major part of the joining region remained on 2p‐, while the joining region has moved to 8q+ in the cell lines BL21 and LY66. In all three cell lines the constant kappa light chain gene was found on the 8q+ chromosome. The fact that an essentially identical pattern was found in the cell line BL21, with the complex translocation, suggests that the insertion of the piece of chromosome 9 into the 8q+ chromosome might be a secondary event. Our present data fit into the concept that in all Burkitt lymphoma lines investigated so far, including cases with t(8;14) and the variant translocations t(2;8) and t(8;22), the c‐myc gene becomes situated at the 5′ side of an immunoglobulin constant gene. This may have implications for the generation of somatic mutations in the coding and non‐coding part of the c‐myc gene.

We have used an approach based on the observation of CpG‐rich regions near the 5′ end of many genes to screen a panel of cosmids derived from the t‐complex and tested candidate sequences for evidence of transcription in a number of different mouse tissues. One gene so identified is expressed specifically in testicular germ cells and maps to a subregion of the t‐complex also containing loci involved in transmission ratio distortion and male sterility. The transcript is first detected during the pachytene stage of the first meiotic division, but is expressed in highest levels in the later haploid spermatogenic stages. Sequence analysis verified the existence of a CpG‐rich element on the 5′ end of the gene and predicts a unique protein species with no significant homologies to those previously determined.

The human Xp21.3-p22.1 region is poorly mapped relative to other X chromosome regions. To target cosmid and YAC clones specifically from Xp21.3-p22.1 for rapid contig construction, a hybridization-based screening approach using irradiation hybrids has been used. Alu-PCR products generated from hybrid lines containing small overlapping fragments from Xp21-p22 were hybridized to an X chromosome cosmid library, and cosmids predicted by their hybridization pattern to map to the region of interest were analyzed by fluorescence in situ hybridization (FISH). Hybridization of the cosmids in pools to gridded YAC libraries identified 15 YACs, which were verified and tested for chimerism by FISH. Cosmid content analysis of the YACs defined two contigs, one with 12 YACs covering about 1.5 Mb and one with 3 YACs. Five YACs from the 12-YAC cluster had been previously recognized by DNA polymerase alpha (POLA). ZFX identified a single YAC; hence, the physical linkage of ZFX and POLA was demonstrated within the contig. Four YACs had been isolated previously with ZFX and these extend the contig to 2 Mb. Restriction mapping of several YACs demonstrates that ZFX and POLA are about 700 kb apart, a distance similar to that reported in the mouse between Zfx and Pola. The order of these two loci and two additional loci identified by homologous mouse linking clones was found to be conserved between human and mouse: tel-ZFX-DXCrc57-DXCrc140-POLA-cen. We have shown that YAC contigs can be rapidly constructed from targeted regions without the need for time-consuming YAC end rescue and chromosomal walking. This approach also generates a series of ordered cosmids, which is particularly valuable for marker generation in regions in which disease gene localization is hampered by low marker density. Copyright 1994, 1999 Academic Press

The class III receptor tyrosine kinase FLT3/FLK2 (FLT3; CD135) represents an important molecule involved in early steps of hematopoiesis. Here we compare cell-surface expression of FLT3 on bone marrow (BM) and cord blood (CB) cells using monoclonal antibodies (MoAbs) specific for the extracellular domain of human FLT3. Flow cytometric analysis of MACS-purified BM and CB cells showed that 63% to 82% of BM CD34+ and 88% to 95% of the CB CD34+ cells coexpress FLT3. Clonogenic assays and morphological characterization of FACS-sorted BM CD34+ cells demonstrate that colony-forming unit–granulocyte-macrophage (CFU-GM) and immature myelo-monocytic precursor cells are enriched in the subpopulation staining most brightly with the FLT3 MoAb whereas the majority of the burst-forming units-erythroid (BTU-E) and small cells with lymphoid morphology are found in the FLT3- population. In contrast, statistically indistinguishable proportions of CFU-granulocyte-erythrocyte-megakaryocyte-macrophage (CFU-GEMM) and more primitive cobblestone area forming cells (CAFC) were detected in both fractions, albeit the FLT3+ fraction consistently showed more CAFC activity than the FLT3- fraction. Although in both, BM and CB the majority of CD34+CD117+ (KIT+), CD34+CD90+ (Thy-1+), and CD34+CD109+ cells coexpress FLT3, three-color phenotypic analyses are consistent with the functional findings and suggest that the most primitive cells defined as CD34+CD38-, CD34+CD71low, CD34+HLA-DR-, CD34+CD117low, CD34+CD90+, and CD34+CD109+ express low levels of cell-surface FLT3 and were therefore not enriched to a statistically significant extent with the bright versus negative sorting scheme. Thus, clear segregation of the most primitive progenitors from BM CD34+ cells was confounded by low apparent levels of FLT3 cell-surface expression on these cells, whereas myeloid progenitors unambiguously segregated with the FLT3 brightest cells and erythroid progenitors with the FLT3 dimmest. Additional phenotypic analyses using MoAbs against progenitor/stem cell markers including the mucinlike molecule MGC-24v (CD164), the receptor tyrosine kinases TIE, FMS (CD115), and KIT (CD117) further illustrate the differences in surface antigen expression profiles of BM and CB CD34+ cells. Notably, CD115 is rarely detected on CB CD34+ cells, whereas 20% to 25% of the BM CD34+FLT3+ cells are CD115+. Furthermore, 80% to 95% of the CB CD34+CD117+ but only 60% to 75% of the BM CD34+CD117+ cells coexpress FLT3. Only a negligible amount of CD34+CD19+ are detected in CB, while in BM 20% to 30% of CD34+CD19+ presumed pro/pre-B cells coexpress FLT3. In contrast, the majority of the CD34+CD164+ and CD34+TIE+ subsets in both CB and BM coexpress FLT3. Analysis of unseparated cells showed that FLT3 expression is not restricted to CD34+ subsets. About 65% to 70% of lymphocyte-gated BM CD34-FLT3+ cells are positive for the monocytic marker CD115 whereas 25% to 30% of these cells consist of CD10 expressing B-cell precursors. Finally, CD34- monocytes in BM, CB, and PB express FLT3 whereas granulocytes are FLT3-. Our data show that detectable FLT3 appears first at low levels on the surface of primitive multilineage progenitor cells and disappears during defined stages of B-cell development, but is upregulated and maintained during monocytic maturation. © 1997 by The American Society of Hematology.

The ligand for flt-3 (FLT3L) exhibits striking structural homology with stem cell factor (SCF ) and monocyte colony-stimulating factor (M-CSF ) and also acts in synergy with a range of other hematopoietic growth factors (HGF ). In this study, we show that FLT3L responsive hematopoietic progenitor cells (HPC) are CD34+CD38-, rhodamine 123dull, and hydroperoxycyclophosphamide (4-HC) resistant. To investigate the basis for the capacity of FLT3L to augment the de novo generation of myeloid progenitors from CD34+CD38- cells, single bone marrow CD34+CD38- cells were sorted into Terasaki wells containing serum-free medium supplemented with interleukin-3 (IL-3), IL-6, granulocyte colony-stimulating factor (G-CSF ), SCF (4 HGF ) ± FLT3L. Under these conditions, FLT3L recruited approximately twofold more CD34+CD38- cells into division than 4 HGF alone. The enhanced proliferative response to FLT3L was evident by day 3 and was maintained at all subsequent time points examined. In accord with these findings, we also show that transduction of CD34+CD38- cells with the LAPSN retrovirus is enhanced by FLT3L. The results of these experiments therefore indicate that increased recruitment of primitive HPC into cell cycle underlies the ex vivo expansion potential of FLT3L and also its ability to improve retroviral transduction of HPC.

CD164 is a novel 80- to 90-kD mucin-like molecule expressed by human CD34+ hematopoietic progenitor cells. Our previous results suggest that this receptor may play a key role in hematopoiesis by facilitating the adhesion of CD34+ cells to bone marrow stroma and by negatively regulating CD34+hematopoietic progenitor cell growth. These functional effects are mediated by at least two spatially distinct epitopes, defined by the monoclonal antibodies (MoAbs), 103B2/9E10 and 105A5. In this report, we show that these MoAbs, together with two other CD164 MoAbs, N6B6 and 67D2, show distinct patterns of reactivity when analyzed on hematopoietic cells from normal human bone marrow, umbilical cord blood, and peripheral blood. Flow cytometric analyses revealed that, on average, 63% to 82% of human bone marrow and 55% to 93% of cord blood CD34+ cells are CD164+, with expression of the 105A5 epitope being more variable than that of the other identified epitopes. Extensive multiparameter flow cytometric analyses were performed on cells expressing the 103B2/9E10 functional epitope. These analyses showed that the majority (>90%) of CD34+ human bone marrow and cord blood cells that were CD38lo/- or that coexpressed AC133, CD90(Thy-1), CD117(c-kit), or CD135(FLT-3) were CD164(103B2/9E10)+. This CD164 epitope was generally detected on a significant proportion of CD34+CD71lo/- or CD34+CD33lo/- cells. In accord with our previous in vitro progenitor assay data, these phenotypes suggest that the CD164(103B2/9E10) epitope is expressed by a very primitive hematopoietic progenitor cell subset. It is of particular interest to note that the CD34+CD164(103B2/9E10)lo/-cells in bone marrow are mainly CD19+ B-cell precursors, with the CD164(103B2/9E10) epitope subsequently appearing on CD34lo/-CD19+ and CD34lo/-CD20+ B cells in bone marrow, but being virtually absent from B cells in the peripheral blood. Further analyses of the CD34lo/-CD164(103B2/9E10)+ subsets indicated that one of the most prominent populations consists of maturing erythroid cells. The expression of the CD164(103B2/9E10) epitope precedes the appearance of the glycophorin C, glycophorin A, and band III erythroid lineage markers but is lost on terminal differentiation of the erythroid cells. Expression of this CD164(103B2/9E10) epitope is also found on developing myelomonocytic cells in bone marrow, being downregulated on mature neutrophils but maintained on monocytes in the peripheral blood. We have extended these studies further by identifying Pl artificial chromosome (PAC) clones containing the CD164 gene and have used these to localize the CD164 gene specifically to human chromosome 6q21. © 1998 by The American Society of Hematology.

A young male with a karyotype of 46, X,+mar is described. Physical mapping of the marker chromosome by using Y-specific single-copy or moderately repeated DNA sequences as molecular probes showed that, in addition to the heterochromatic part of the Yq, a considerable portion of the euchromatin in both Yp and Yq had been lost. These findings suggest that the marker chromosome is a ring Y, for the generally accepted model of ring formation implies breakages in both chromosome arms. The clinical features of the patient correlated well with the phenotypic changes expected from the loss of genetic material from the Y.

Meiotic recombination in the yeast Saccharomyces cerevisiae is initiated at double-strand breaks (DSBs), which occur preferentially at specific locations1–3. Genetically mapped regions of elevated meiotic recombination (‘hotspots’) coincide with meioticDSB sites, which can be identified on chromosome blots of meiotic DNA (refs 4,5; S.K. et al., manuscript submitted). The morphology of yeast artificial chromosomes (YACs) containing human DNA during the pachytene stage of meiosis resembles that of native yeast chromosomes6. Homologous YAC pairs segregate faithfully and recombine at the high rates characteristic of S. cerevisiae7(vs. ∼0.4 cM/kb in S. cerevisiae versus ∼10−3cM/kb in humans). We have examined a variety of YACs carrying human DNA inserts for double-strand breakage during yeast meiosis. Each YAC has a characteristic set of meiotic DSB sites, as do yeast chromosomes (S.K. et al., manuscript submitted). We show that the positions of the DSB sites in the YACs depend on the human-derived DNA in the clones. The degree of double-strand breakage in yeast meiosis of the YACs in our study appears to reflect the degree of meiotic recombination in humans.