bluuebunny/crossref_metadata_2025 huggingface dataset:
An unusual FGFR1 mutation (fibroblast growth factor receptor 1 mutation) in a girl with non-syndromic trigonocephaly
Authors: Kress W. , Petersen B. , Collmann H. , Grimm T.
Published: April 2003

Non-syndromic trigonocephaly is a heterogeneous entity; in most cases the origin is unknown. Rare cases with autosomal dominant and recessive inheritance exist. Here the mutational screening of ten patients in the FGFR1, 2, and 3 genes and the TWIST gene causative of autosomal dominant craniosynostosis syndromes was reported. In one girl an unusual FGFR1 mutation was found.
Parent-offspring resemblance of palmar and plantar dermatoglyphic patterns in Down syndrome
Authors: Langenbeck U. , Herzberger G. , Kümmerle S.
Published: April 2003

With the aim of investigating the influence of trisomy 21 on the expression of heritable morphological features, we recorded the palmar and plantar dermatoglyphic patterns in 48 children with Down syndrome (DS), in both their parents, and, as a control, in 57 of their siblings. Using the Kendall tau rank correlation test, a considerable parental influence on the frequency of true patterns in the interdigital areas (IDA) III and IV of the palms (P = 0.3%) and soles (P = 1.0% and 3.8%, respectively) is demonstrated for the control siblings. In the children with DS, this influence is discernible as well, although with no statistical significance. A greater number of families may be required to settle the question.
Discrepancies in cytogenetic results between different tissues in two fetuses with Wolf- Hirschhorn syndrome
Authors: Schinzel A.
Published: April 2003

Discrepant unbalanced structural chromosome aberrations between placental and fetal tissue, both involving the short arm of chromosome 4, were found in two human fetuses affected with Wolf-Hirschhorn syndrome. In the first instance, placental chromosome examination revealed a del(4) (p14), whereas fetal fibroblast chromosomes showed an unbalanced der(4)t(4;13)(p14;q11) translocation. In the second instance, placental karyotyping revealed a 4p+ chromosome, while amniocytes showed a submicroscopic deletion at 4p16.3. Since confirmation of structural aberrations from placental tissue is mostly not sought if the phenotype of the fetus is abnor- mal, discrepancies between karyotypes obtained from placental tissue and amniocytes or fetal tissues might be more frequent than the rare reports published so far would suggest. It is unclear whether the simple deletion or the more complex rearrangement is the primary aberration from which the other derived. Structural chromosome aberrations often have a much more complex mechanism of formation than the end product would suggest, and secondary rearrangements of a given aberration in the zygote are more frequent than expected.
Female pseudohermaphroditism caused by caudal dysgenesis
Authors: Wieacker P. , Grumpelt U. , Schulz T.O. , Gharavi B. , Avenarius S. , Jakubiczka S. , Stumm M.
Published: April 2003

We report on two cases of female pseudohermaphroditism associated with anorectal, Müllerian duct, and urinary tract malformations. We suggest that this form of female pseudohermaphroditism is an extreme manifestation of the caudal type of VATER association.
Unequal nondisjunction frequencies of trivalent chromosomes in male mice heterozygous for two Robertsonian translocations
Authors: Winking H. , Reuter C. , Bostelmann H.
Published: April 2003

Robertsonian (Rb) translocation heterozygosity may cause pairing problems during prophase and segregation irregularities at anaphase of meiosis I. These stages of meiosis I were studied in male mice doubly heterozygous for the two Rb chromosomes Rb(9.19)163H and Rb(16.17)8Lub. At pachytene both Rb chromosomes similarly showed pairing irregularities like unpaired segments. However, highly different nondisjunction frequencies of chromosomes forming the respective trivalents were found. The nondisjunction frequency of the Rb8Lub trivalent chromosomes was about 40%, whereas a very low frequency of nondisjunction was found in combination with the Rb163H trivalent. Since both trivalents were together in the same cell, differences in kinetochore function are assumed to be responsible for the diverse frequency of nondisjunction.
Improvement of FISH mapping resolution on combed DNA molecules by iterative constrained deconvolution: a quantitative study
Authors: Monier K. , Heliot L. , Rougeulle C. , Heard E. , Robert-Nicoud M. , Vourc’h, C. , Bensimon A. , Usson Y.
Published: April 2003

Image restoration approaches, such as digital deconvolution, are becoming widely used for improving the quality of microscopic images. However, no quantification of the gain in resolution of fluorescence images is available. We show that, after iterative constrained deconvolution, fluorescent cosmid signals appear to be 25% smaller, and 1.2-kb fragment signals on combed molecules faithfully display the expected length.
A mitotically stable marker chromosome negative for whole chromosome libraries, centromere probes and chromosome specific telomere regions: a novel class of supernumerary marker chromosome?
Authors: Mackie Ogilvie C. , Harrison R.H. , Horsley S.W. , Hodgson S.V. , Kearney L.
Published: April 2003

A two year-old child presented with mild developmental delay. On karyotype analysis, a supernumerary small marker chromosome (SMC) was found in all cells examined. This SMC was approximately the size of an isochromosome 18p, being symmetrical with a central constriction. C-banding and silver staining were negative and FISH with all chromosome-specific paints, centromere probes and telomere probes showed no hybridization to the SMC; telomere repeat sequences were however present on both arms. Comparative genomic hybridization showed no amplification of any chromosome region. Flow sorting of the SMC and reverse painting onto normal metaphase spreads showed no hybridization to any chromosome, whereas reverse painting onto the patient’s own metaphases showed hybridization to the SMC only. This SMC may thus represent either a complex amplicon of different genomic regions, or a multifold amplification of a very small region, with a neocentromere comprising an active kinetochore but no alphoid DNA. Prognostic implications for the proband were difficult to assess due to the absence of reports of similar marker chromosomes in the literature.
Genomic organization and promoter identification of ZNF146, a gene encoding a protein consisting solely of zinc finger domains
Authors: Pibouin L. , Villaudy J. , Prospéri M.-T. , Goubin G.
Published: April 2003

The ZNF146 gene (alias OZF) encodes a protein consisting solely of ten zinc finger motifs. It is amplified and overexpressed in pancreatic carcinomas. To better understand the mechanisms controlling its expression, we have isolated the human ZNF146 gene and performed an initial assessment of its promoter activity. ZNF146 encompasses 25 kb of sequence and consists of four non-coding exons located upstream of a single coding exon. The sequence of proximal 1.4 kb of ZNF146 promoter has a high GC content, is devoid of a TATA box and contains several potential transcriptional elements. This region directs high-level expression of a transfected reporter construct in human cell lines. Analysis of a series of 5′-deletion constructs indicated that the first 80 bp upstream of the potential start site of transcription carry minimal promoter activity whereas the first 550 bp are required for maximal promoter activity.
The functional Myosin Light Chain Kinase (MYLK) gene localizes with marker D3S3552 on human chromosome 3q21 in a >5-Mb yeast artificial chromosome region and is not linked to olfactory receptor genes
Authors: Giorgi D. , Brand-Arpon V. , Rouquier S.
Published: April 2003

The myosin light chain kinase (MYLK) gene is duplicated on human chromosome 3 (3q13→q21; 3p13), two sites known to contain olfactory receptor (OR) genes. The 3p13 site contains a MYLK pseudogene (MYLKP) associated with a cluster of OR pseudogenes and therefore could have arisen from the duplication of a large region in 3q13→q21. Here, we present the localization of the MYLK gene in a >5-Mb region of the chromosome 3q21 integrated map. MYLK colocalizes with marker D3S3552. OR genes are absent from this region, suggesting that the 3p13 duplicated region incurred further rearrangements during evolution.
The murine GABAB receptor 1: cDNA cloning, tissue distribution, structure of the Gabbr1 gene, and mapping to chromosome 17
Authors: Lamp, K. , Humeny, A. , Nikolic, Z. , Imai, K. , Adamski, J. , Schiebel, K. , Becker C.-M.
Published: April 2003

GABA (γ-aminobutyric acid) is a major inhibitory neurotransmitter in the central nervous system (CNS) which activates both ionotropic (GABAA/GABAC) and metabotropic (GABAB) receptor systems. We identified two alternatively spliced cDNA variants of the murine GABAB receptor 1 that are predominantly expressed in the CNS. Deduced protein structures are highly homologous to the previously characterized rat and human receptors. Comparison of the genomic structures of mouse and human revealed that alternative splicing occurred at the same position, whereas the mouse gene has an additional 5′ exon. Radiation hybrid mapping, combined with database searches, indicated that the GABAB receptor gene (Gabbr1) is located on mouse chromosome 17, adjacent to the marker D17Mit24 in a region homologous to human chromosome 6p21.3.
Improved radiation hybrid map of rat chromosome 2: colocalization of the genes encoding corticotropin-releasing hormone and IL6-receptor with quantitative trait loci regulating the inflammatory response
Authors: Laes J.-F. , Ravoet M. , Quan X. , van Vooren P. , Szpirer J. , Szpirer C.
Published: April 2003

We established a radiation hybrid (RH) map of several genes and anonymous markers in the lower half of rat chromosome 2, a chromosome region that contains quantitative trait loci (QTLs) for blood pressure, diabetes and inflammatory response. Two of the newly localized genes (Crh and Il6r) encode proteins involved in the regulation of inflammatory and immune events. Our data show that they reside within regions that were genetically defined as QTLs controlling the inflammatory response. These genes are thus both functional and positional candidates.
Conservation of chromosome 1 in turtles over 66 million years
Authors: Mühlmann-Díaz M.C. , Ulsh B.A. , Whicker F.W. , Hinton T.G. , Congdon J.D. , Robinson J.F. , Bedford J.S.
Published: April 2003

Fluorescence in situ hybridization of a whole chromosome 1–specific probe from the yellow-bellied slider turtle (Trachemys scripta) to cells from four other species of turtle ranging from a desert tortoise to a loggerhead sea turtle resulted in specific and exclusive hybridization to chromosome 1 in all five species. Previous observations of conservation in the giemsa banding pattern and chromosome morphology and number among turtles are thus extended to the DNA sequence level, revealing a cytogenetic stability of chromosome 1 in these turtles during the past 66–144 million years. This contrasts with the situation for various hominoid species where, in many instances, extensive chromosomal rearrangements have been reported in one third of that time period. Our probe, which was prepared by microdissecting whole chromosomes from embryonic T. scripta fibroblasts and amplifying using DOP-PCR, is the first report of a whole-chromosome FISH probe for any reptile.
Induction and characterization of hypoxanthine-phosphoribosyltransferase (Hprt–) deficient cell lines of Akodon cursor (Rodentia, Sigmodontinae)
Authors: Bonvicino, C.R. , Moreira, M.A.M. , Arcuri, R.A. , Seuánez H.N.
Published: April 2003

Hypoxanthine-phosphoribosyltransferase negative (Hprt–) cell lines derived from an Akodon cursor liposarcoma were obtained by induced mutagenesis. All but one Hprt– cell line lacked Hprt mRNA transcripts while one (AKO 3) coded for a truncated protein. Cell fusion and karyotypic analyses showed that one cell line (AKO 1-15) could be successfully used for constructing hybrid panels and allow for a clear identification of human chromosomes in hybrid cells.
Polymorphism and polytypy for pericentric inversions in 38-chromosome Mastomys (Rodentia, Murinae) and possible taxonomic implications
Authors: Volobouev V.T. , Hoffmann A. , Sicard B. , Granjon L.
Published: April 2003

Chromosome banding analysis (R- and C-bands) of two 38-chromosome Mastomys specimens originating from the Ivory Coast and Uganda revealed different numbers of autosome arms (NFa), equal to 51 and 60, respectively. Comparison of their chromosome banding patterns with those of Mastomys specimens from the Sudan (NFa = 41) and Senegal (NFa = 51–54), studied previously, showed that variation of the NFa from 40 to 60 throughout the species distribution is the result of a pericentric inversion polymorphism involving 3–12 chromosome pairs. At the population level, this variation is much narrower and never results from more than two chromosome pairs involved in inversion polymorphism. Taking into account that the NFa values recorded to date form a well-defined discontinuous row, we presume that introgressive hybridization between populations differing from each other by 3–5 to 11–12 pericentric inversions is interrupted. From there, the hypothesis of the existence of at least three cryptic species (designated provisionally as MER-1, MER-2, and MER-3) within 38-chromosome Mastomys populations previously assigned to M. erythroleucus can be made. It looks likely that one of them, possessing a karyotype with an NFa = 50–56, is widely distributed throughout sub-Saharan Africa and includes karyotyped populations from Senegal, the Ivory Coast, Mali, Benin, Cameroon, Zaire, and the Sudan. The second species (MER-2) includes the specimens karyotyped (NFa = 40–41) from Chad and the Sudan. Finally, a third tentative species (MER-3) corresponds to specimens with NFa = 59–60 found in East Zaire and Uganda, as well as possibly Mali and Chad.
Phylogenetic implications of the 38 putative ancestral chromosome segments for four canid species
Authors: Graphodatsky A.S. , Yang F. , O’Brien P.C.M. , Perelman P. , Milne B.S. , Serdukova N. , Kawada S-I. , Ferguson-Smith M.A.
Published: April 2003

Chromosome homologies between the Japanese raccoon dog (Nectereutes procyonoides viverrinus, 2n = 39 + 2–4 B chromosomes) and domestic dog (Canis familiaris, 2n = 78) have been established by hybridizing a complete set of canine paint probes onto high-resolution G-banded chromosomes of the raccoon dog. Dog chromosomes 1, 13, and 19 each correspond to two raccoon dog chromosome segments, while the remaining 35 dog autosomes each correspond to a single segment. In total, 38 dog autosome paints revealed 41 conserved segments in the raccoon dog. The use of dog painting probes has enabled integration of the raccoon dog chromosomes into the previously established comparative map for the domestic dog, Arctic fox (Alopex lagopus), and red fox (Vulpes vulpes). Extensive chromosome arm homologies were found among chromosomes of the red fox, Arctic fox, and raccoon dog. Contradicting previous findings, our results show that the raccoon dog does not share a single biarmed autosome in common with the Arctic fox, red fox, or domestic cat. Comparative analysis of the distribution patterns of conserved chromosome segments revealed by dog paints in the genomes of the canids, cats, and human reveals 38 ancestral autosome segments. These segments could represent the ancestral chromosome arms in the karyotype of the most recent ancestor of the Canidae family, which we suggest could have had a low diploid number, based on comparisons with outgroup species.
cDNA cloning, chromosomal localization and evolutionary analysis of mouse vacuolar ATPase subunit D, Atp6m
Authors: Kennell J.A. , Richards N.W. , Schaner P.E. , Gumucio D.L.
Published: April 2003

The multi-subunit vacuolar ATPase pump uses ATP hydrolysis to move protons into membrane bound compartments. The pump is involved in a variety of cellular functions, including regulation of cytosolic pH, vesicular transport, endocytosis, secretion, and apoptosis. Here, we describe the cDNA cloning and chromosomal mapping of subunit D of murine V-ATPase. The mouse gene, designated Atp6m, maps to Chromosome 12, in a region of high homology with human chromosome 14q24. Evolutionary analysis of subunit D orthologs in a variety of other species reveals that this is a highly conserved protein that has been under remarkably strong negative selection during evolution, most likely reflecting its critical role in multiple cellular processes.
Use of primed in situ labeling (PRINS) for the detection of telomeric deletions associated with mental retardation
Authors: Bonifacio S. , Centrone C. , Da Prato L. , Scordo M.R. , Estienne M. , Torricelli F.
Published: April 2003

Rearrangements involving the telomeric regions of human chromosomes are often associated with mental retardation. These rearrangements, however, are difficult to detect using conventional cytogenetic techniques. We propose the use of primed in situ (PRINS) labeling as an alternative to fluorescence in situ hybridization because it is very fast, reproducible, and simple to perform. Sixty-five children with unexplained mental retardation were studied using PRINS technology; two of them were shown to have a telomeric deletion.
Genomic organization and mapping of the gene (SLC25A19) encoding the human mitochondrial deoxynucleotide carrier (DNC)
Authors: Iacobazzi V. , Ventura M. , Fiermonte G. , Prezioso G. , Rocchi M. , Palmieri F.
Published: April 2003

The deoxynucleotide carrier (DNC) transports deoxynucleotides into mitochondria and is therefore essential for mtDNA synthesis. The human DNC gene (SLC25A19) spans about 16.5 kb and consists of nine exons with the translation start site in exon 4. It is located on chromosome 17q25.3. Three transcripts, which differ in their 5′ ends and are generated by alternative splicing, have been identified.
Characterization and chromosomal localization of five canine ATOX1 pseudogenes
Authors: van de Sluis B. , Nanji M.S. , Breen M. , Pearson P.L. , Oost B.A. , Cox D.W. , Wijmenga C.
Published: April 2003

We have isolated six ATOX1 loci from the canine genome in BAC clones. Sequence analysis showed that five of these clones correspond to processed pseudogenes. Fluorescent in situ hybridization allowed us to map the genuine ATOX1 gene to CFA4q24→q31 and the ATOX1 pseudogenes to CFA19q13.1, CFA4q24→q31, CFA18q24→q25, CFA9q22.1 →q22.2 and CFA20q11→q12.
Sequence polymorphisms, allelic expression status and chromosome locations of the chicken IGF2 and MPR1 genes
Authors: Yokomine T. , Kuroiwa A. , Tanaka K. , Tsudzuki M. , Matsuda Y. , Sasaki H.
Published: April 2003

By screening 26 chicken breeds and lines, DNA polymorphisms were identified in the IGF2 and MPR1 genes, of which mammalian homologues are parentally imprinted, and the GAPD gene, a housekeeping control. Using the polymorphisms as genetic markers, we found that all three genes are expressed biallelically in embryonic tissues. IGF2 and MPR1 were mapped on chicken chromosomes 5 and 3, respectively, by fluorescence in situ hybridization, demonstrating conserved linkage homology between mammals and birds.
Two supernumerary marker chromosomes, originating from chromosomes 6 and 11, in a child with developmental delay and craniofacial dysmorphism
Authors: Maurer B. , Haaf T. , Stout K. , Reissmann N. , Steinlein C. , Schmid M.
Published: April 2003

The interpretation of the significance of marker chromosomes, which can be encountered at prenatal diagnosis, is extremely problematic. Various factors contribute to the difficulty of clarifying the phenotypic risks of supernumerary marker chromosomes, including differences in the size, structure, and origin of marker chromosomes, as well as the occurrence of multiple marker chromosomes of different origin in the same proband. Research on marker chromosomes is currently in a data-accumulation phase. We report the presence of two marker chromosomes, originating from chromosomes 6 and 11, in a child with developmental delay and craniofacial dysmorphism and discuss the related literature.
Biased distribution of repetitive elements: a landmark for neo-Y chromosome evolution in Drosophila miranda
Authors: Steinemann S. , Steinemann M.
Published: April 2003

It is generally assumed that the sex chromosomes developed from a pair of homologs. Over evolution, the proto-Y chromosome, with a very short differential segment, matured in its final stage into a heterochromatic and, for the most part, genetically eroded Y chromosome. The constraints on the evolution of the proto-Y chromosome have been speculated upon since the sex chromosomes were discovered. Several models have been suggested. Drosophila miranda has proved to be a unique and potent model system to study Y-chromosome evolution. We use selected test genes distributed along the neo-Y chromosome as entry gates to analyze the molecular mechanisms involved in the process of Y-chromosome evolution. Here, we report our findings on the Krüppel gene (Kr), which is located distally on the neo-sex chromosome pair.
Chicken microchromosomes are hypermethylated and can be identified by specific painting probes
Authors: Grützner F. , Zend-Ajusch E. , Stout K. , Munsche S. , Niveleau A. , Nanda I. , Schmid M. , Haaf T.
Published: April 2003

Microdissection of single chicken microchromosomes (MICs) followed by degenerate oligonucleotide-primed (DOP) PCR allows the rapid generation of MIC-specific DNA libraries. Since some libraries derived from a single (or a few) chromosome(s) label the entire MIC fraction, the majority of chicken MICs share repetitive DNA sequences that are not found on the macrochromosomes. In evolutionarily distant bird species, MICs are invariably hypermethylated. Methylcytosine staining provides additional in situ evidence for the high gene content of MICs and strong compartmentalization of avian genomes.
Chromosome homologies between man and mountain zebra (Equus zebra hartmannae) and description of a new ancestral synteny involving sequences homologous to human chromosomes 4 and 8
Authors: Richard F. , Messaoudi C. , Lombard M. , Dutrillaux B.
Published: April 2003

Using human chromosome painting probes, we looked for homologies between human and mountain zebra (Equus zebra hartmannae, Equidae, Perissodactyla) karyotypes. Except for two very short segments, all euchromatic regions were found to have a human homologous chromosome segment. Conserved syntenies previously described in various mammalian orders were detected. Each synteny corresponded to a chromosomal region homologous to two parts of human chromosomes: HSA3 and HSA21, HSA7 and HSA16, HSA12 and HSA22, and HSA16 and HSA19. Chromosomal segments homologous to a part of HSA11 and HSA19p are found syntenic in zebra, horse and donkey, suggesting that this group of synteny has been inherited from an Equidae or Perissodactyla common ancestor. A synteny of segments homologous to parts of HSA4 and HSA8 was observed in zebra and horse. It also exists in the rabbit (Lagomorpha) and several Carnivora species. A second group of taxa which does not have this region of synteny is composed of primates, Chiroptera and Insectivora, and possibly also Cetacea and Scandantia. Thus, the presence or absence of this region of synteny may separate two groups of eutherian mammals.
Molecular cloning, structure and expression of a novel nuclear RNA-binding cyclophilin-like gene (PPIL4) from human fetal brain
Authors: Zeng L. , Zhou Z. , Xu J. , Zhao W. , Wang W. , Huang Y. , Cheng C. , Xu M. , Xie Y. , Mao Y.
Published: April 2003

The cyclophilins are members of a highly conserved, ubiquitous family, and play an important role in protein folding, immunosuppression by cyclosporin A (CsA), and infection of HIV-1 virions. Here we report that a novel member of the cyclophilin family, PPIL4, was cloned and identified during the large-scale sequencing analysis from a human fetal brain cDNA library. The PPIL4 gene encodes a protein which shares 96% amino acid identity with a protein encoded by a putative gene recently cloned from several different early stages of mouse embryo, and its homologues are found in several other organisms. According to bioinformatics analysis, the PPIL4 gene was found to be located in chromosome 6q24→q25. Besides the PPIase motif, PPIL4 also has an RNA recognition motif (RRM), a pair of bipartite nuclear targeting sequences, and a lysine rich domain. RT-PCR analysis indicated that PPIL4 gene expression is abundant in kidney but has a ubiquitously low expression pattern in other human adult tissues.
cDNA cloning, genomic organization and expression of the novel human metallophosphoesterase gene MPPE1 on chromosome 18p11.2
Authors: Vuoristo J.T. , Ala-Kokko L.
Published: April 2003

We have isolated a 1,926-bp cDNA that encodes a novel polypeptide of 396 amino acid residues with a calculated molecular mass of 45.2 kDa. This MPPE1 polypeptide consists of a predicted signal sequence of 45 residues at the N-terminus, a 240-amino acid metallo-phosphoesterase domain, and a 24-amino acid transmembrane domain at the C-terminus. The genomic organization of the human MPPE1 gene proved to consist of 14 exons and to span about 27 kb. The gene was located on chromosome 18p11.2, adjacent to the G protein Golf alpha gene (GNAL), in tail-to-tail orientation, partially overlapping with the 3′ UTR of the latter gene. MPPE1 is expressed as an mRNA of 2.2 kb in the brain, but not in any other tissues studied here. 3′ RACE analysis defined a single functional polyadenylation site within the 3′ UTR of the GNAL gene, while RT-PCR analysis revealed an alternatively spliced form of MPPE1, which included an additional exon located within the last intron. The alternatively spliced form encoded a truncated variant of MPPE1 with a calculated molecular mass of 38.8 kDa that lacks the C-terminal transmembrane domain.
XX:XY sex chromosome system with X heterochromatinization: an early stage of sex chromosome differentiation in the Neotropic electric eel Eigenmannia virescens
Authors: de Almeida-Toledo L.F. , Foresti F. , Péquignot E.V. , Daniel-Silva M.F.Z.
Published: April 2003

An early stage of sex chromosome differentiation is reported to occur in the electric eel Eigenmannia virescens (Pisces, Sternopygidae) from populations of two tributaries of the Paraná river system (Brazil). Cytogenetic studies carried out in the two populations showed that the Mogi-Guaçu population is characterized by 2n = 38 chromosomes and undifferentiated sex chromosomes and the Tietê population presents 2n = 38 both for males and females and an XX:XY sex chromosome system. The X-chromosome is acrocentric, easily recognized by the presence of a conspicuous heterochromatin block in its distal portion; the Y-chromosome is probably one of the medium sized acrocentrics present in the male karyotype. BrdU induced R-bands of the two populations did not reveal any difference in the euchromatic regions of the chromosomes. AluI and HaeIII restriction enzyme digestion patterns and chromomycin A3 staining of the X-chromosome are presented. The possible role of heterochromatinization in the evolution of sex chromosomes in fish is discussed.
A comparative cytogenetic study of chromosome homology between chicken and Japanese quail
Authors: Shibusawa M. , Minai S. , Nishida-Umehara C. , Suzuki T. , Mano T. , Yamada K. , Namikawa T. , Matsuda Y.
Published: April 2003

In order to construct a chicken (Gallus gallus) cytogenetic map, we isolated 134 genomic DNA clones as new cytogenetic markers from a chicken cosmid DNA library, and mapped these clones to chicken chromosomes by fluorescence in situ hybridization. Forty-five and 89 out of 134 clones were localized to macrochromosomes and microchromosomes, respectively. The 45 clones, which localized to chicken macrochromosomes (Chromosomes 1–8 and the Z chromosome) were used for comparative mapping of Japanese quail (Coturnix japonica). The chromosome locations of the DNA clones and their gene orders in Japanese quail were quite similar to those of chicken, while Japanese quail differed from chicken in chromosomes 1, 2, 4 and 8. We specified the breakpoints of pericentric inversions in chromosomes 1 and 2 by adding mapping data of 13 functional genes using chicken cDNA clones. The presence of a pericentric inversion was also confirmed in chromosome 8. We speculate that more than two rearrangements are contained in the centromeric region of chromosome 4. All 30 clones that mapped to chicken microchromosomes also localized to Japanese quail microchromosomes, suggesting that chromosome homology is highly conserved between chicken and Japanese quail and that few chromosome rearrangements occurred in the evolution of the two species.
Life Markers in Biographical Narratives of People from Three Cohorts: A Life Span Perspective in Its Historical Context
Authors: Grob Alexander , Krings Franciska , Bangerter Adrian
Published: April 2003

Human development is often understood as an interplay between biological, sociohistorical, and social factors, as well as individual developmental actions. However, historical influences on development have rarely been investigated. The present study discusses societal change in the course of this century and investigates its impact on the life course by analyzing biographical narratives. This impact is illustrated by results from a study where participants from three birth cohorts (1920–25; 1945–50; 1970–75) were interviewed about important markers in their experienced and expected biographies. Although distribution of life markers over the life span was analogous across cohorts, participants from the younger cohorts perceived themselves as having more control on setting important life markers across their biographies. Their narratives referred more often to personal and less often to contextual and sociohistorical themes.
Always Under Construction
Authors: Yan Zheng , Fischer Kurt
Published: April 2003

People’s activities vary dynamically from moment to moment, and analysis of level of skill complexity in successive activities provides a tool to portray and analyze variation as skills are learned. Systematic examination of these variations is crucial for illuminating the dynamic nature of learning and development – the ways that people construct activities under the influence of multiple factors interacting in complex ways, in context, over time. A study of adults learning to use a computer program illustrates three important patterns in the dynamic variation of adult cognitive microdevelopment: (1) each person’s performance levels vary within a range between upper and lower attractors during dynamic construction of a skill. (2) Performance moves through different pathways from a novice pattern to a transitional pattern characterized by scalloping (repeated building up and collapse of complex performance) to an expert pattern. Social scaffolding plays an important role in moving a learner toward the upper attractor. (3) Each person functions at diverse levels depending on demands of the task, domain, background, scaffolding, and capacity and thus shows asynchrony in level, not simple consistency. Tasks and situations attract specific skill levels that are often below people’s highest capacities.
Albumin Turnover in Renal Disease
Authors: Kaysen George A.
Published: April 2003

Hypoalbuminemia is found in patients both with the nephrotic syndrome and with end-stage renal disease (ESRD) treated either with continuous ambulatory peritoneal dialysis (CAPD) or hemodialysis. In nephrotic patients the primary causes of hypoalbuminemia are urinary albumin losses, an inappropriate increase in the fractional catabolic rate (FCR) of albumin and an insufficient increase in the rate of albumin synthesis to replace these losses. Nevertheless, the albumin synthetic rate is increased significantly. In patients on CAPD, albumin losses into the urine and across the peritoneal membrane contribute significantly to hypoalbuminemia. In contrast to nephrotic patients, albumin FCR decreases as serum albumin falls and serum albumin levels are significantly greater than in nephrotic patients with the same external losses of albumin. CAPD patients, like nephrotic patients with normal renal function, can increase albumin synthesis to replace losses. Thus ESRD does not directly suppress albumin synthesis. In contrast, hypoalbuminemia in hemodialysis patients results from reduced albumin synthesis. The cause of decreased albumin synthesis is a combination of response to inflammation (acute-phase response) and, to a lesser extent, inadequate nutrition. There is no evidence that shifts of albumin to the extravascular space or that dilution of the plasma by volume expansion play any role in causing hypoalbuminemia in ESRD or nephrotic patients.
TGF-β in Renal Allograft Rejection
Authors: Cohen Arthur H. , Nast Cynthia C.
Published: April 2003

The role of TGF-β in pathological processes in the transplanted kidney is beginning to be investigated both in animal models and in humans. In both settings in acute cell-mediated rejection, TGF-β, receptor, and message have all been documented to be elevated in the tubulointerstitium, likely a reflection of TGF-β’s role in recruiting leukocytes to areas of injury and downregulation of the inflammatory response. In chronic rejection, expression of TGF-β, message, and induced proteins is elevated, especially in cortex. TGF-β mRNA, unlike other inflammatory cytokine mRNAs, correlated very well with interstitial fibrosis, a hallmark of chronic rejection. Thus, a relationship between renal scarring and TGF-β has been documented by most studies of transplant kidneys. Additionally, this growth factor also appears to have a role in the renal fibrosis associated with cyclosporine administration and perhaps in augmenting this drug’s immunosuppressive effects.
Effects of a Meat Meal on Renal Sodium Handling and Sodium Balance
Authors: Cirillo Massimo , Anastasio Pietro , Spitali Lucia , Santoro Domenico , De Santo Natale G.
Published: April 2003

Protein ingestion increases renal blood flow and glomerular filtration rate (GFR). This study investigated in healthy adults if the renal response to protein ingestion includes changes in urinary sodium (Na) excretion rate and Na balance. Renal clearance of Na and inulin (used as index of GFR) were measured in 25 healthy adults before (90 min) and after (180 min) a standard meal and, as control, before and after administration of water and Na-chloride (saline). The meal consisted of red lean meat (2 g protein/kg body weight); in control experiments, water and Na were given to match water and Na content of the meal. ANOVA for repeated measures, Student’s t-test, and linear regression were used for statistical analysis. GFR and urinary Na excretion increased over baseline after the meal (p < 0.001), not after saline. The post-meal natriuretic response was accounted for an early (0–90 min) increase in glomerular filtered load of Na (p < 0.001) and a late (90–180 min) reduction in tubular Na reabsorption (p < 0.02). Urine flow rate and plasma Na did not significantly change after the meal and in control experiments. Analysis of Na balance showed that post-meal Na excretion was significantly higher than baseline also after Na balance returned to pre-meal values. In healthy individuals, a meat meal stimulates natriuresis and causes a net decrease in Na balance. The renal natriuretic response to the meal appears secondary to the meal-induced changes in renal hemodynamics. The data are in keeping with the hypothesis that dietary protein intake affects also renal Na handling.
Diuretic Resistance
Authors: Suki Wadi
Published: April 2003

Resistance to diuretic action is frequently encountered in the clinical setting. This is best managed by systematically optimizing the pharmacodynamic-pharmacokinetic factors that may be involved. Important pharmacodynamic measures include improving the underlying disease state, restriction of salt intake, limiting the use of vasodilators which may cause hypotension, lowering protein excretion, and eliminating drugs which may modify the response to the diuretic. Pharmacokinetic measures include using doses which result in diuretic excretion rates which fall on the steep part of the dose-response curve, sustaining diuretic excretion in this range by frequent drug administration, or constant infusion, using more bioavailable drugs and drugs which have less hepatic elimination, and by increasing the diuretic concentration in blood by coadministration with albumin. Using diuretic combinations to systematically inhibit absorption in the proximal tubule, Henle''s loop, distal convoluted tubule, and connecting/collecting tubule will usually effect diuresis in all but the most refractory of cases.
Diuretics in Renal Failure
Authors: Andreucci Michele , Russo Domenico , Fuiano Giorgio , Minutolo Roberto , Andreucci Vittorio
Published: April 2003

Fluid retention following reduction in the glomerular filtration rate causes extracellular fluid volume expansion that reduces tubular reabsorption by residual nephrons, thereby maintaining the external sodium balance. The price paid for this is salt-dependent hypertension. Thus, loop diuretics are the best treatment for uremic hypertension. Diuretics are also used in chronic renal failure to treat edema due to nephrotic syndrome and congestive heart failure (CHF). In nephrotics, edema is often refractory to diuretics because of low plasma protein, depletion of the intravascular compartment, decrease in the protein-bound fraction of the diuretic in peritubular blood, and increase in tubular fluid. Thus, higher doses are needed. In uremics with CHF the efficacy of diuretics may be hampered because of the reduced renal blood flow. The association of dopamine (1–1.5 µg/kg body weight/min) may overcome this resistance; improvement in cardiac function by dialysis ultrafiltration may also help. Diuretic resistance is sometimes observed; it may be overcome by the following procedures: in CHF by the use of digitalis and/or angiotensin-converting enzyme inhibitors; by substitution of an ineffective loop diuretic for another one; by using larger doses of diuretic; by intravenous infusion rather than bolus therapy, and by a combination of diuretics acting in different segments of the tubule: loop diuretic+thiazide+amiloride. Intravenous infusion of 20% albumin has also been suggested.
Systolic Hypertension: The Nephrologist’s Point of View
Authors: Cirillo Massimo , Stellato Davide , De Santo Natale
Published: April 2003

The elevation of systolic blood pressure associated with aging has been considered for years a physiologic phenomenon. This idea was based on the repeated observation that, also after middle age, a large majority of individuals in industrialized countries experience a continuous and progressive increase over time in systolic blood pressure, not in diastolic blood pressure. However, some individuals in industrialized countries and most individuals in nonindustrialized countries do not acquire an increased systolic blood pressure over time proving that the age-associated rise in systolic blood pressure is not an inevitable phenomenon. The change in systolic blood pressure over time strongly reflects lifestyles. Diet-dependent factors such as body weight, alcohol intake, and balance between dietary salt and potassium, are important in favoring the age-associated increase in systolic blood pressure, independently of several confounders. Epidemiologic studies suggest that elevation of systolic blood pressure is a risk factor for cardiovascular diseases: it relates to high incidence of lethal and nonlethal cardiovascular events also in the presence of diastolic blood pressure in the nonhypertensive range. Controlled clinical trials show that the treatment of isolated systolic hypertension reduces the number of cardiovascular events. In addition to cardiovascular disease, systolic blood pressure relates also to microalbuminuria, an index of early glomerular damage, to long-term incidence of end-stage renal disease, and, in hemodialyzed patients, to premature death. Thus, high systolic blood pressure appears an unhealthy condition also for patients with or at risk for kidney diseases.
Effects of Acidosis on Acute Phase Protein Metabolism in Liver Cells
Authors: Ulrich Christof , Krüger Bernd , Köhler Hans , Riegel Werner
Published: April 2003

Metabolic acidosis has been shown to act as a causative factor in muscle protein breakdown and negative nitrogen balance, as well as in decreased albumin synthesis. Albumin and other acute phase proteins (APP) are mainly synthesized in the liver following induction by interleukins, hormones and other mediators. Acute phase proteins have been shown to be predictors of cardiovascular mortality in the general population and in patients with end stage renal disease (ESRD). Clinical investigation gives evidence that albumin is reduced by acidosis in ESRD patients. The aim of our study was to investigate the role of the liver in acidosis, i.e. the influence of acidosis on metabolic activity and secretion of APP by liver cells (HepG2). Cells were cultured in a medium containing different amounts of bicarbonate. Metabolic activity was significantly diminished when the bicarbonate concentration of the extracellular medium was reduced (86.13±1.90% (pH 7.0) vs. 99.53±90% (pH 7.4); p<0.01). While cellular release of negative APP was significantly decreased (albumin: 4.6±0.41 (pH 7.0) vs. 7.54±0.62 (pH 7.4) [ng/µg protein], p<0.001, transferrin: (0.78±0.08 (pH 7.0) vs. 1.07±0.07 (pH 7.4) [ng/µg protein], p<0.05), no significant influence of acidosis (pH 7.0) on the positive APP, α1-acid glycoprotein (AGP) (1.69±0.25) (pH 7.0) vs. 1.62±0.23 (pH 7.4) [ng/µg protein]), could be shown. Our data indicate that acidosis results in inhibition of liver cell metabolic activity and in reduced secretion of the negative acute phase proteins albumin and transferrin. In contrast, secretion of the positive acute phase protein AGP seems to be unchanged at pH 7.0 as compared to pH 7.4. We conclude that negative and positive APP in liver cells (HepG2) appear to be differently regulated by acidosis.
High Protein/Energy vs. Standard Protein/Energy Nutritional Regimen in the Treatment of Malnourished Hemodialysis Patients
Authors: Kuhlmann Martin , Schmidt Felix , Köhler Hans
Published: April 2003

Although malnutrition is frequently encountered in maintenance hemodialysis (MHD) patients, a clear method of treating this complication is still lacking. Failure of nutritional support regimens may be due to inadequate support of dietary needs. Therefore, a high vs. standard or low protein/energy dietary regimen was studied in malnourished MHD patients. A total of 18 malnourished MHD patients selected according to subjective global assessment (SGA)-scores and biochemical indicators of malnutrition (serum albumin <40 g/l, cholesterol <200 mg/dl, prealbumin <30 mg/dl; two out of three) were assigned to three treatment groups: (A: 45 kcal/kg/d and 1.5 g protein/kg/d; B: 35 kcal/kg/d and 1.2 g protein/kg/d; C: spontaneous intake supplemented with 10% of mean protein and energy intake). A and B received food supplements at appropriate dosing to reach the targeted nutritional intake. During 3-month follow-up nutrient intake was assessed by repeated 4-day dietary diaries. Compliance and tolerance was good in each group. Weight gain (1.2±0.4 kg) was observed in group A, but not in B and C. Serum albumin levels increased by 1.0±0.5 g/l in group A, but not in B and C. Prealbumin and cholesterol levels were unaffected. Weight change correlated with mean dietary energy intake, but not with mean dietary protein intake. We conclude that prescription of 45 kcal/kg/d and 1.5 g protein/kg/d may be necessary to achieve weight gain and improvement of nutritional indices in malnourished MHD pts. Oral food supplements can be used safely and effectively to increase nutrient intake to high levels in these patients.
Metabolic Adjuvants to Erythropoietin Therapy
Authors: Macdougall Iain
Published: April 2003

It is possible to potentiate the response to epoetin by co-administering other agents. In some instances, this response is seen when there is a deficiency of a certain substance. In other cases, administration of an adjuvant such as intravenous iron, vitamin D, L-carnitine, or androgens can enhance the response to epoetin when given as a surfeit. With most of these agents, with perhaps the exception of intravenous iron, further research is required to determine the exact role they may play in clinical practice. As long as the cost of epoetin therapy remains fairly high, the challenge will continue as to the best way of optimizing its effect, and we can look forward to new developments in this expanding area of research.
Glomerular Expression of α2(IV) and α5(IV) Chains of Type IV Collagen in Patients with IgA Nephropathy
Authors: Kamimura Hirokazu , Honda Kazuho , Nitta Kosaku , Horita Shigeru , Kobayashi Hideo , Uchida Keiko , Yamaguchi Yutaka , Yumura Wako , Nihei Hiroshi
Published: April 2003

IgA nephropathy (IgAN) frequently accompanies glomerular basement membrane (GBM) alterations. To clarify the compositional changes of the GBM in IgAN, we examined the glomerular expression of α2(IV) and α5(IV) chains of type IV collagen in 36 patients with IgAN. Increased expression of the α2(IV) chain was observed in the expanded mesangium, and there were segmental sclerotic lesions of glomeruli in which the expression of the α5(IV) chain in the GBM was reduced. These lesions were found in 11 out of the 36 patients (30.6%). The patients with these lesions had more proteinuria, lower creatinine clearance and severer histological changes than the patients without them. On the other hand, a partial reduction of α5(IV) chain in normal-appearing GBM was observed in 15 out of the 36 patients (41.7%). The patients with this lesion had a longer disease period before biopsy than the patients without it. No other clinical and histological parameters were related to the partial reduction of α5(IV) in the GBM. In conclusion, an imbalance of glomerular α2(IV) and α5(IV) chain expression occurred in IgAN. This may be associated with the morphological changes of glomerular sclerosis and GBM alterations in IgAN. Further studies are required to understand the pathogenesis of the abnormal expression of type IV collagen chains.