bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of the Y chromosome in chinook salmon (Oncorhynchus tshawytscha)
Authors: Stein J. , Phillips R.B. , Devlin R.H.
Published: April 2003

The Y chromosome in chinook salmon, Oncorhynchus tshawytscha, was identified using fluorescence in situ hybridization (FISH) with a probe to a male-specific repetitive sequence isolated from this species. The probe highlights the distal end of the short arm of an acrocentric chromosome with a DAPI-bright interstitial band of variable size. The proximal portion of the short arm of the Y chromosome contains 5S rDNA sequences, which are also found on the short arms of six other acrocentric chromosomes in this species.
Isolation, characterization and FISH assignments of horse BAC clones containing type I and II markers
Authors: Mariat D. , Oustry-Vaiman A. , Cribiu E.P. , Raudsepp T. , Chowdhary B.P. , Guérin G.
Published: April 2003

In order to increase the number of markers on the horse cytogenetic map and expand the integration with the linkage map, an equine BAC library was screened for genes and for microsatellites. Eighty-nine intra-exon primers were designed from consensus gene sequences in documented species. After PCR screening, 38 clones containing identified genes were isolated and FISH mapped. These data allowed us to refine the available Zoo-FISH results, to define ten new conserved cytogenetic segments and expand two others, thus leading to the identification of a total of 26 conserved segments between horse and human. Interestingly, a new homeology segment was detected between ECA6p and HSA2q. Screening BAC clones for dinucleotide repeats led to the isolation of 33 microsatellites. Ten of the clones each contained at least a polymorphic microsatellite and one specific gene. The success of the approach in the production of integrative anchor loci and their potential use in localization and analysis of traits of interest by the candidate gene and positional cloning approach, are discussed.
Concomitant DNA copy number amplification at 17q and 22q in dermatofibrosarcoma protuberans
Authors: Kiuru-Kuhlefelt S. , El-Rifai W. , Fanburg-Smith J. , Kere J. , Miettinen M. , Knuutila S.
Published: April 2003

Dermatofibrosarcoma protuberans (DFSP) is a tumor of low or intermediate malignant potential with a tendency for recurrence, but low rate of metastasis. The tumorigenesis of DFSP has recently been shown to be associated with the fusion of the collagen type I alpha 1 (COL1A1) and platelet-derived growth factor B-chain (PDGFB) genes, often as a consequence of translocation t(17;22)(q22;q13). Cytogenetically, DFSP is often characterized by supernumerary ring chromosomes containing material from chromosomes 17 and 22. A subset of DFSPs undergo fibrosarcomatous transformation de novo or upon recurrence, and contain components indistinguishable from fibrosarcoma (FS-DFSP). The fibrosarcomatous transformation appears to carry an increased risk for recurrence and metastasis, and is considered to represent tumor progression. The molecular cytogenetic events contributing to tumor progression are unknown. We used comparative genomic hybridization to analyze DNA copy number changes in 11 cases of typical DFSP and 10 cases of FS-DFSP. All cases in both groups were found to exhibit a gain or high-level amplification on chromosome 17q and the majority also on 22q. This finding is in line with previous studies, and suggests further that not only the COL1A1/PDGFB fusion gene formation but also the role of DNA copy number gains in the 17q and 22q regions is crucial per se in the pathogenesis of DFSP. Even though FS-DFSPs displayed a trend toward increase in the number of DNA copy number changes, the difference was not statistically significant, which indicates that mechanisms other than copy number changes are important in the transformation process of DFSP.
Molecular cloning and characterization of a novel peptidylprolyl isomerase (cyclophilin)-like gene (PPIL3) from human fetal brain
Authors: Zhou Z. , Ying K. , Dai J. , Tang R. , Wang W. , Huang Y. , Zhao W. , Xie Y. , Mao Y.
Published: April 2003

During the large-scale sequencing analysis of a human fetal brain cDNA library, we isolated two cDNA clones encoding two novel proteins, which show 52% and 72% identity to the cyclophilin isoform 10 of C. elegans, respectively. Sequence analysis revealed these two cDNA clones are two different splicing variants of a novel cyclophilin-like gene (PPIL3). The PPIL3 gene was identified on a completely sequenced BAC (GenBank accession AC005037) from chromosome 2q33 between STS markers stSG2762 (proximal) and SHGC-3074 (distal), oriented toward the telomere. The PPIL3 gene consisted of eight exons spanning more than 18 kb of genomic DNA. RT-PCR analysis indicated that PPIL3 was ubiquitously expressed in adult human tissues.
Cloning and chromosome mapping of human and chicken Iroquois (IRX) genes
Authors: Ogura K. , Matsumoto K. , Kuroiwa A. , Isobe T. , Otoguro T. , Jurecic V. , Baldini A. , Matsuda Y. , Ogura T.
Published: April 2003

Three highly homologous homeobox genes (caupolican, araucan and mirror) have been identified in Drosophila. These genes belong to the novel Iroquois complex, which acts as a pre-pattern molecule in Drosophila neurogenesis. Recently several vertebrate Iroquois homologues (Irx) were isolated and found to be involved in pattern formation of various tissues. Here we report cytogenetic mapping of four human and five chicken Iroquois genes by FISH. Our findings revealed that vertebrate Irx genes are clustered at two different loci.
Structure and chromosome location of the mouse P2X1 purinoceptor gene (P2rx1)
Authors: Liang S.X. , Jenkins N.A. , Gilbert D.J. , Copeland N.G. , Phillips W.D.
Published: April 2003

P2X1 receptors are ATP-gated cation channels that mediate the fast, purinergic component of sympathetic nerve–smooth muscle neurotransmission in the mouse vas deferens and may serve comparable functions in the urinary bladder and the arteries. The gene for mouse P2X1 (P2rx1) was cloned and its genomic structure defined by sequencing. The gene spans about 10 kb and consists of 12 exons. All splice sites conformed to the GT-AG motif and the exon-intron boundaries were largely conserved with other members of the P2X gene family so far cloned. A single transcription-starting site was identified by 5′ RACE analysis, 233 bp upstream of the translation start site. The P2X1 gene maps to the central region of mouse chromosome 11.
Expression and chromosome location of hamster Ku70 and Ku80
Authors: Koike M. , Kuroiwa A. , Koike A. , Shiomi T. , Matsuda Y.
Published: April 2003

Ku proteins play an important role in DNA double-strand break (DSB) repair, chromosome maintenance, and growth regulation. To understand the fundamental characteristics of Ku proteins, we examined the electrophoretic mobility and expression of hamster Ku70 and Ku80 and determined the chromosome locations of their genes. The electrophoretic mobility of hamster Ku proteins are different from that of human Ku proteins. No significant changes in the quantity of Ku proteins were observed in CHO-K1 cells treated with 10 Gy of ionizing radiation, suggesting that both proteins are expressed constitutively in amounts adequate to repair DNA DSBs. The chromosome locations of the Ku genes were determined by direct R-banding fluorescence in situ hybridization. The Ku70 gene was localized to Syrian hamster chromosome 4qa4.1→ qa4.2 and Chinese hamster chromosome 2p3.1, and the Ku80 gene was localized to Syrian hamster chromosome 4qb5→ qb6.1 and Chinese hamster chromosome 2p3.5→p3.6. These results provide clues to the biological functions of Ku, as well as useful information for constructing comparative chromosome maps between hamsters and other mammalian species, including human, mouse, and rat.
Molecular characterization and chromosome assignment of the porcine gene for leukemia inhibitory factor LIF
Authors: Spötter A. , Drögemüller C. , Kuiper H. , Brenig B. , Leeb T. , Distl O.
Published: April 2003

Leukemia inhibitory factor (LIF) is a pleiotropic cytokine involved in early conceptus development in pig. We isolated a PAC clone containing the porcine LIF gene and determined the complete DNA sequence of the gene, which spans about 6.3 kb and consists of five exons including three alternative first exons (1D, 1M, 1T) spliced onto common second and third exons. The LIF-D transcript encodes a protein of 202 amino acids sharing 87, 84, and 78% identity with respectively human, ovine, and murine leukemia inhibitory factors. The LIF-M and LIF-T transcripts both encode a truncated protein of 158 amino acids. Two SNP markers within untranslated regions of the LIF cDNA were identified. One SNP is located in the 5′-UTR of the alternative exon 1T while the other SNP is located in the 3′-UTR of exon 3. Based on fluorescence in situ hybridization and radiation hybrid mapping, the porcine LIF gene was assigned to chromosome 14q2.1→q2.2.
Genomic organization, chromosome location, and expression analysis of mouse β-synuclein, acandidate for involvement in neurodegeneration
Authors: Sopher B.L. , Koszdin K.L. , McClain M.E. , Myrick S.B. , Martinez R.A. , Smith A.C. , La Spada A.R.
Published: April 2003

The synuclein family of proteins is a group of primarily brain-expressed polypeptides that show a high degree of amino acid conservation. α-Synuclein is the best known of the synuclein family, as it is a major component of the Lewy body, a cytoplasmic inclusion characteristic of Parkinson’s disease as well as a variety of related neurodegenerative disorders. With the discovery that mutations in α-synuclein can cause Parkinson’s disease, a potential role for the other synuclein family members in neurodegenerative disease is being considered. β-Synuclein in particular may deserve special attention, as it is co-expressed with α-synuclein at presynaptic nerve terminals, is subject to phosphorylation by Ca2+ calmodulin protein kinase II, appears important for neural plasticity, and forms aggregates in the brains of patients with Parkinson’s disease and a related disorder. To facilitate study of β-synuclein, we have cloned the mouse β-synuclein gene (Sncb) and determined its genomic organization, size, and intron-exon structure. Using an interspecific backcross mapping panel from The Jackson Laboratory, we were then able to localize Sncb to chromosome 13 at the MGD 35.0 cM position. Like the human β-synuclein gene, Sncb appears to consist of six exons separated by five introns. Unlike the human β-synuclein gene, the mouse ortholog possesses a variant GC 5′ splice donor sequence at the exon 4 – intron 4 boundary in a highly conserved splice junction consensus. Northern blot analysis and Western blot analysis both indicate that Sncb is highly expressed in the brain. Knowledge of the genomic organization and expression pattern of Sncb will allow functional studies of its potential role in neurodegeneration to commence in the mouse.
Re-defining the chromatin loop domain
Authors: Heng H.H.Q. , Krawetz S.A. , Lu W. , Bremer S. , Liu G. , Ye C.J.
Published: April 2003

It is commonly accepted that the loop domain represents the basic structural unit of eukaryotic chromatin associated with DNA replication, gene expression and higher order packaging. However, molecular-cytological information defining the loop domain is lacking. There are gaps in our knowledge of the loop structure and how it regulates gene expression. The combination of new data/reagents from the Human Genome Project plus the use of novel molecular cytological technology will provide answers. Here we briefly review the status of chromatin loop research and pose questions that need to be addressed. New experimental systems are also presented to target some long-standing issues regarding the structure and function of the chromatin loop domain and its relationship with the nuclear matrix. This new knowledge will have a profound impact for modern genetics and molecular medicine.
Unusual chromosomal mosaicism as a cause of mental retardation and congenital malformations in a familial reciprocal translocation carrier, t(17;22)(q24.2;q11.23)
Authors: Dufke A. , Mayrhofer H. , Enders H. , Kaiser P. , Leipoldt M.
Published: April 2003

Familial reciprocal translocations are generally without phenotypic effect, although there is some evidence for a small excess of mental retardation and congenital malformations (MR/CM) in children carrying familial reciprocal translocations. Possible mechanisms whereby such translocations could have a phenotypic effect include cryptic unbalanced rearrangements, uniparental disomy, and disruption of putative genes at the breakpoints, unmasking recessive alleles on the normal homologs. Mosaicism for a supernumerary derivative chromosome in a carrier of a familial reciprocal translocation has not yet been described. We report a boy presenting with MR/CM and a familial reciprocal translocation, t(17;22)(q24.2;q11.23), inherited from the mother. Cytogenetic analysis of peripheral blood lymphocytes showed a balanced karyotype in all 32 analyzed metaphase spreads. Molecular genetic analysis was consistent with biparental origin of the normal homologs. In metaphase spreads from skin fibroblasts a supernumerary chromosome was found in all 24 cells analyzed and could be identified as der(22)t(17;22)(q24.2;q11.23). Several possible segregation modes at meiosis I followed by meiosis II or postzygotic nondisjunction of the der(22) might have led to this unusual chromosomal mosaicism. We propose hidden mosaicism as a possible cause for MR/CM in patients who apparently carry a balanced familial reciprocal translocation.
The combination of SKY and specific loci detection with FISH or immunostaining
Authors: Ye C.J. , Lu W. , Liu G. , Bremer S.W. , Wang Y.A. , Moens P. , Hughes M. , Krawetz S.A. , Heng H.H.Q.
Published: April 2003

Spectral karyotyping (SKY) represents an effective tool to detect individual chromosomes and analyze major karyotype abnormalities within an entire genome. We have tested the feasibility of combining SKY and FISH/protein detection in order to combine SKY’s unique abilities with specific loci detection. Our experimental results demonstrate that various combined protocols involving SKY, FISH and immunostaining work well when proper procedures are used. This combined approach allows the tracking of key genes or targeted chromosome regions while monitoring changes throughout the whole genome. It is particularly useful when simultaneously monitoring the behavior of both protein complexes and DNA loci within the genome. The details of this methodology are described and systematically tested in this communication.
Genomic organization of the human NFAT5 gene: exon-intron structure of the 14-kb transcript and CpG-island analysis of the promoter region
Authors: Dalski A. , Schwinger E. , Zühlke C.
Published: April 2003

NFAT5, also known as tonicity enhancer binding protein (TonEBP) or NFATL1, is a new member of the immunologically important NFAT protein family. Despite its obvious relationship to this transcription factor family, NFAT5 shows distinct ways of regulation and function. The complete coding sequence and its alternative splice forms have been described previously. This sequence only refers to less than half of the total mRNA length. High conservation of this gene was shown among man, mouse, and pig. Here we report the cloning of the complete 14-kb cDNA sequence, its genomic organization, and a possible fourth isoform of the corresponding protein. Additionally, we describe the promoter region by CpG-island methylation analysis.
Comparative cytogenetics of the African elephant (Loxodonta africana) and Asiatic elephant (Elephas maximus)
Authors: Houck M.L. , Kumamoto A.T. , Gallagher Jr D.S. , Benirschke K.
Published: April 2003

G- and C-banded karyotypes of the two extant species of the mammalian order Proboscidea are presented for the first time. Chromosome complements were 2n = 56 in both Loxodonta africana and Elephas maximus. Comparisons between the species demonstrated a high level of chromosome band homology, with 26 conserved autosomal pairs. The normal diploid karyotype of L. africana had 25 acrocentric/telocentric and two metacentric/submetacentric autosomal pairs. E. maximus differed by having one less acrocentric and one additional submetacentric pair due to either a heterochromatic arm addition or deletion involving autosomal pair 27. Several acrocentric autosomes of L. africana exhibited small short arms that were absent in homologous chromosomes of E. maximus. The X chromosomes in both species were large submetacentric elements and were homologous. However, the small acrocentric Y chromosomes differed; in E. maximus it was slightly larger and had more distinct G-bands than its counterpart in L. africana. Extant Elephantidae appear to be relatively conservative in their rates of chromosomal change compared to some other mammalian families. The high-quality banded karyotypes presented here should prove useful as references in future chromosome analyses of elephant populations and in comparative cytogenetic studies with other ungulate orders.
Ts65Dn – localization of the translocation breakpoint and trisomic gene content in a mouse model for Down syndrome
Authors: Akeson E.C. , Lambert J.P. , Narayanswami S. , Gardiner K. , Bechtel L.J. , Davisson M.T.
Published: April 2003

Fluorescent in situ hybridization (FISH) – using mouse chromosome paints, probes for the mouse major centromeric satellite DNA, and probes for genes on chromosomes (Chr) 16 and 17 – was employed to locate the breakpoint in a translocation used to produce a mouse model for Down syndrome. The Ts65Dn trisomy is derived from the reciprocal translocation T(16;17)65Dn. The Ts65Dn mouse carries a marker chromosome containing the distal segment of Chr 16, a region that shows linkage conservation with human Chr 21, and the proximal end of Chr 17. This chromosome confers trisomy for most of the genes in the Chr 16 segment and Ts65Dn mice show many of the phenotypic features characteristic of Down syndrome. We used FISH on metaphase chromosomes from translocation T65Dn/+ heterozygotes and Ts65Dn mice to show that the Chr 17 breakpoint is distal to the heterochromatin of Chr 17, that the Ts65Dn marker chromosome contains a small portion of Chr 17 euchromatin, that the Chr 16 breakpoint lies between the Ncam2 and Gabpa/App genes, and that the Ts65Dn chromosome contains >80% of the human Chr 21 homologs. The significance of this finding is discussed in terms of the utility of this mouse model.
Comparative genomic sequencing reveals a strikingly similar architecture of a conserved syntenic region on human chromosome 11p15.3 (including gene ST5) and mouse chromosome 7
Authors: Amid C. , Bahr A. , Mujica A. , Sampson N. , Bikar S.-E. , Winterpacht A. , Zabel B. , Hankeln T. , Schmidt E.R.
Published: April 2003

Comparative genomics is a superior way to identify phylogenetically conserved features like genes or regions involved in gene regulation. The comparison of extended orthologous chromosomal regions should also reveal other characteristic traits essential for chromosome or gene function. In the present study we have sequenced and compared a region of conserved synteny from human chromosome 11p15.3 and mouse chromosome 7. In human, this region is known to contain several genes involved in the development of various disorders like Beckwith-Wiedemann overgrowth syndrome and other tumor diseases. Furthermore, in the neighboring chromosome region 11p15.5 extensive imprinting of genes has been reported which might extend to region 11p15.3. The analysis of approximately 730 kb in human and 620 kb in mouse led to the identification of eleven genes. All putative genes found in the mouse DNA were also present in the same order and orientation in the human chromosome. However, in the human DNA one putative gene of unknown function could be identified which is not present in the orthologous position of the mouse chromosome. The sequence similarity between human and mouse is higher in transcribed and exon regions than in non-transcribed segments. Dot plot analysis, however, reveals a surprisingly well-conserved sequence similarity over the entire analyzed region. In particular, the positions of CpG islands, short regions of very high GC content in the 5′ region of putative genes, are similar in human and mouse. With respect to base composition, two distinct segments of significantly different GC content exist as well in human as in the mouse. With a GC content of 45% the one segment would correspond to “isochore H1” and the other segment (39% GC in human, 40% GC in mouse) to “isochore L1/L2”. The gene density (one gene per 66 kb) is slightly higher than the average calculated for the complete human genome (one gene per 90 kb). The comparison of the number and distribution of repetitive elements shows that the proportion of human DNA made up by interspersed repeats (43.8%) is significantly higher than in the corresponding mouse DNA (30.1%). This partly explains why the human DNA is longer between the landmark genes used to define the orthologous positions in human and mouse.
Molecular cloning and characterization of a novel human gene (HSPBAP1) from human fetal brain
Authors: Jiang M. , Ma Y. , Cheng H. , Ni X. , Guo L. , Xie Y. , Mao Y.
Published: April 2003

Rat PASS1 is a novel protein binding specifically to hsp27 and thus plays a role in regulating stress response in the living cell. Here we report on a human homologue of PASS1, encoded by the gene HSPBAP1. The gene was cloned and identified during a large-scale sequencing analysis of a human fetal brain cDNA library. The human protein shared 80% amino acid identity with rat PASS1. According to bioinformatics analysis, the HSPBAP1 gene is located on chromosome 3q21. RT-PCR analysis indicated that HSPBAP1 was abundant in thymus and pancreas but had a ubiquitously low expression pattern in other human adult tissues except for brain where it was absent.
Genetic and physical mapping, expression analysis and partial sequence of porcine PER1
Authors: Skinner T.M. , Lopez-Corrales N.L. , Anderson S.I. , Loudon A.S.I. , Lowden S. , Haley C.S. , Archibald A.L.
Published: April 2003

The porcine PER1 gene was mapped to chromosome 12q1.4→q1.5 using fluorescence in situ hybridisation. A polymorphic microsatellite marker (S0601) was isolated from a BAC clone shown to contain the PER1 gene. Linkage analysis assigned S0601 distal to ALOX12 on SSC12, providing further evidence for the conservation of synteny between HSA17 and SSC12. RT-PCR analysis demonstrated the expression of PER1 in all 11 tissues tested, consistent with the data from other mammalian species. Part of the PER1 gene was sequenced, homologous to exons 2–14 of the human gene and encoding the N-terminus of porcine PER1. The predicted amino acid sequence of the partial pig PER1 protein shares over 96% identity with its human orthologue.
The Constitution of General and Specific Mental Models of Other People
Authors: Oura Yoko , Hatano Giyoo
Published: April 2003

This article is about how novices become experts in the domain of piano playing, focusing on how they develop internalized models of other people, a form of culture in the mind. Six novice and nine junior expert college students were individually asked to practice a short piece of music; they were asked to verbalize what they thought during the exercise about the performance they were executing and how they planned to perform it after their practice sessions had been concluded. The novices seemed to have internalized a generalized ‘other’ in their mind, who commanded them to perform accurately and smoothly as goals of the exercise. The junior experts seemed to possess also a model of the audience in their mind, from the perspective of whom they could check and refine their performance. Interviews with two concert class pianists showed that they possessed not only generalized others but also specific others in their mind and could refine their performance based on these models. How experts can be creative in spite of a set of constraints posed by the culture is discussed.
Low-Dosage Intravenous Immunoglobulin in the Management of a Patient with Acquired von Willebrand Syndrome Associated with Monoclonal Gammopathy of Undetermined Significance
Authors: Hayashi T. , Yagi H. , Suzuki H. , Nonaka Y. , Nomura T. , Sakurai Y. , Shibata M. , Matsumoto M. , Yamamoto Y. , Fujimura Y.
Published: April 2003

We report herein the case of a 69-year-old Japanese man with acquired von Willebrand syndrome associated with monoclonal gammopathy of undetermined significance who developed IgG1-ĸ antibodies against von Willebrand factor (VWF). The patient was urged to undergo tooth extractions because of alveolar pyorrhea, and a low-dosage intravenous immunoglobulin (IV-Ig) therapy (0.3 g of IgG/kg/day for 3 days) was chosen for him. On the 4th day after the infusion, VWF antigen and VWF ristocetin cofactor increased to 40 and 78% of the control, respectively, and dental extractions were performed successfully. On the 7th day, these values reached a maximum, i.e. 95 and 160% of the control, respectively. Then, they quickly decreased to 35 and 75% on the 10th day, and 6 months later, they became 16 and <3% of the control, respectively. Upon analysis of plasma VWF multimers (VWFMs) in this patient, those with large to medium molecular masses more selectively disappeared before the IV-Ig infusion than did those with small molecular masses. On the 4th day, the pattern of VWFMs was completely normalized and appeared to persist until the 10th day. Six months later, a small amount of large to medium-sized VWFMs was still present, but at 7–8 months, the pattern of VWFMs became almost the same as that before infusion. Throughout the patient’s clinical course, the activity of plasma VWF-cleaving protease, which specifically cleaves the Tyr842-Met843 bond of the subunit and reduces its multimeric sizes, was quite normal (95–119%). These results provided consistent evidence that the selective absence of VWFMs with large to medium molecular masses in this patient is caused by the heightened clearance of a complex of IgG inhibitor and VWFMs from the circulation, presumably through IgG binding to the Fc receptor of macrophages. Furthermore, these results also indicated that a low-dosage IV-Ig therapy is effective enough for hemostatic management for programmed surgery.
To General Haemostasis – the Evidence-Based Route
Authors: Erhardtsen Elisabeth
Published: April 2003

Recombinant factor VIIa (rFVIIa) was developed for the treatment of bleeding in haemophilia patients with inhibitors and has also been used successfully in non-haemophilia patients with acquired antibodies against FVIII (acquired haemophilia). Based on dose-finding trials and a compassionate-use programme, rFVIIa was approved for use in haemophilia patients with inhibitors in 1996. At pharmacological doses, rFVIIa has been found to enhance thrombin generation on already activated platelets. Therefore, it is likely that rFVIIa will also be beneficial in providing haemostasis in other situations characterised by profuse bleedings and an impaired thrombin generation. Patients with thrombocytopenia have a decreased number of platelets and thus an impaired thrombin generation. A reduction in bleeding time was reported in approximately 50% of patients with thrombocytopenia and a prolonged bleeding time who participated in a trial of rFVIIa. Moreover, in 8 patients with 9 overt bleeds who were involved in the study, bleeding stopped in 7 episodes after rFVIIa administration. Case reports on the haemostatic effect of rFVIIa in thrombocytopenia have also been published. Reports have also been published on the successful use of rFVIIa in patients with platelet function deficiencies such as Glanzmann’s thrombasthenia and Bernard-Soulier syndrome. A number of haemostatic changes occur after extensive trauma, surgery and bleeding, all of which potentially contribute to an impaired thrombin generation. The effect of rFVIIa has been demonstrated in a number of patients after trauma and bleeds and upper gastrointestinal bleeding episodes. Reports on the beneficial use of rFVIIa in liver transplantation have also been published. Several randomised blinded studies are now underway in e.g. hepatectomy, upper gastrointestinal bleedings, transplantations and intra-cerebral bleeds. In summary, rFVIIa may be an effective and safe method to induce haemostasis in patients within areas of coagulation factor deficiency or platelet disorders and the ongoing and planned randomised studies may lead the way to the use of rFVIIa in general haemostasis.
Osteopontin Expression in the Kidney during Unilateral Ureteral Obstruction
Authors: Kaneto Hiroyuki , Morrissey Jerry , McCracken Ruth , Reyes Alvaro , Klahr Saulo
Published: April 2003

Osteopontin is a bone protein also expressed in other tissues. Increased osteopontin is thought to be associated with tissue inflammation. We used immunocytochemical analyses and polymerase chain reaction amplification of mRNA to examine osteopontin expression and regulation in unilateral ureteral obstruction (UUO) in rats, a model of inflammatory kidney disease. In the obstructed kidney, osteopontin mRNA and protein were significantly increased. The increase reached 4-fold after 1 day of UUO and persisted at this level for the 5-day duration of UUO. Immunocytochemical analyses showed increased osteopontin protein in tubular cells of the obstructed kidney cortex from days 1 through 5 of UUO. No such significant increase was apparent in the glomerulus or interstitium. Increased osteopontin mRNA and protein likewise occurred in the tubular cells of the obstructed kidney of rats that had undergone whole-body irradiation to eliminate macrophage infiltration into the experimental kidney. Purified osteopontin was found to be a chemoattractant for macrophages isolated from the rat peritoneum. Enalapril treatment, which decreases macrophage infiltration of the obstructed kidney, had no effect on the increase in osteopontin mRNA but significantly attenuated the increase in protein in tubular cells. Western blot analysis of whole cortical homogenates revealed that the osteopontin antibody recognized one protein of 67 kD. The amount of this protein was substantially decreased in kidney homogenates obtained from enalapril-treated compared to untreated animals. Increased osteopontin synthesis may, therefore, contribute in part to the inflammatory response that characterizes obstructive nephropathy.
Effects of Recombinant Growth Factors on Energy Expenditure in Maintenance Hemodialysis Patients
Authors: Tabakian Alba , Juillard Laurent , Laville Martine , Joly Marie-Odile , Laville Maurice , Fouque Denis
Published: April 2003

We compared the metabolic effects of recombinant human (rh) insulin-like growth factor (IGF)-1 or a combination of rhIGF-1 + rh growth hormone (GH) on resting energy expenditure (REE) in 8 maintenance hemodialysis (MHD) patients. Seven males and 1 female (aged 41.6 ± (SD) 12.4) with no evidence of malnutrition (BMI 21.6 ± 2.2 kg/m2, serum albumin 45 ± 2 g/l, serum IGF-1 359 ± 165 µg/l) received either rhIGF-1 (80 µg/kg/day) or rhIGF-1 (80 µg/kg/day) + rhGH (50 µg/kg/day) for 3 days in a random crossover design. REE and the respiratory quotient (RQ) were measured at rest before and after the 3-day treatment. The results confirmed that MHD patients have a REE not different from normal individuals. REE was strongly correlated with lean body mass but not with fat mass. rhIGF-1 treatment did not modify REE despite doubling serum IGF-1 values, whereas a combined rhIGF1 + rhGH treatment significantly increased REE by 11% (p < 0.001). There was no change in RQ under both treatments, in response to a proportionate increase in VCO2 and VO2. These results show that energy expenditure is mainly dependent upon lean body mass in well-nourished MHD patients. The metabolic effects of rhIGF-1 and rhGH on energy expenditure may differ in response to their opposite effects on lipid oxidation and insulin regulation.
Magnesium Deficiency Induces Bone Loss in the Rat
Authors: Rude Robert K. , Kirchen Mary E. , Gruber Helen E. , Stasky Audrey A. , Meyer Martha H.
Published: April 2003

Disorders in which magnesium (Mg) depletion is common have an associated high incidence of osteoporosis. Mg depletion in humans results in hypocalcemia, low serum parathyroid hormone (PTH) and 1,25(OH)2-vitamin D levels, as well as PTH and vitamin D resistance which may serve as mechanisms for the development of osteoporosis. In order to determine if isolated Mg depletion will result in bone loss, we have induced dietary Mg deficiency in the rat. Adult (290 g) female rats were given either a low-Mg diet (2 mg/100 g chow; n = 6) or a normal control Mg diet (63 mg/100 g chow; n = 6). Dietary calcium (Ca) was normal in both groups (592 mg/100 g chow). At 12 weeks, blood was obtained for serum Mg, Ca, PTH, 1,25(OH)2-vitamin D, and osteocalcin determinations. The rats were then euthanized and the femurs obtained for mineral analysis and histomorphometry. Serum Mg in the low-Mg group was less than control (0.4 ± 0.2 vs. 1.9 ± 0.2 mg/dl, p < 0.001; mean ± SD) while serum Ca was higher (11.7 ± 0.5 vs. 9.3 ± 0.4 mg/dl, p < 0.001). PTH was suppressed in the Mg-deficient group (36 ± 16 vs. 109 ± 30 pg/ml in controls, p < 0.002). Serum 1,25(OH)2-vitamin D was also suppressed in the Mg-deficient animals (7.1 ± 4.8 vs. 28.5 ± 8.2 pg/ml in controls, p < 0.002). Serum osteocalcin levels were not different (19.8 ± 2.5 ng/ml in Mg-deficient rats vs. 15.3 ± 3.4 ng/ml in controls). While the ash weight of Ca and phosphorus in the femur did not change, the ash weight of Mg fell (low-Mg group 0.55 ± 0.01%, controls 0.65 ± 0.02%, p < 0.001). Histomorphometry demonstrated reduction in bone mass; the trabecular bone volume in the femur of the low-Mg group was reduced from control (7.7 ± 0.2 vs. 13.7 ± 1.9%, p < 0.002). A surprising new observation was an increase in osteoclast (OC) bone resorption with Mg depletion. The number of OC per millimeter bone surface was 16.9 ± 1.3 in the low-Mg group versus 7.8 ± 1.5 in controls (p < 0.001). The percentage of bone surface occupied by OC was 38.3 ± 3.7 in the low-Mg group versus 17.7 ± 2.4 in controls (p < 0.001). This increased resorption occurred with an inappropriate non-altered bone-forming surface relative to control (% osteoid surface: low-Mg group 2.4 ± 0.7 vs. controls 2.6 ± 0.4; % osteoid volume: low-Mg group 0.25 ± 0.09 vs. controls 0.38 ± 0.06; number of osteoblasts per millimeter bone surface: low-Mg group 0.9 ± 0.3 vs. controls 1.3 ± 0.3). No increase in bone-forming surface or osteoblast number despite an increase in OC-resorbing surface and OC number strongly suggests impaired activation of osteoblasts and an uncoupling of bone formation and bone resorption. Our data demonstrate that Mg depletion in the rat alters bone and mineral metabolism which results in bone loss.
Impact of Salt Intake on Blood Pressure and Proteinuria in Diabetes: Importance of the Renin-Angiotensin System
Authors: Weir Matthew
Published: April 2003

Patients with hypertension and diabetes are frequently salt-sensitive. Consequently, increasing dietary salt intake results in a rise in systemic arterial pressure and an increase in proteinuria, as well as a progressive risk for developing renal injury. A difference in the renal hemodynamic response to salt appears, at least in part, to determine how the salt intake affects blood pressure. Greater dietary salt intake in salt-sensitive patients results in a blunted rise in renal plasma flow and an increase in body weight. Greater dietary salt consumption also results in a rise in glomerular filtration fraction and increasing proteinuria. Pharmacologic antagonism of the renin-angiotensin system helps restore the blunted renal plasma flow response to high salt intake and correlates with the fall in mean arterial pressure. Consequently, the pressor response to increasing dietary salt consumption in patients with diabetes and hypertension may be related to insufficient renal vasodilation, perhaps due to inadequate suppression of the renin-angiotensin system. Moreover, inadequate suppression of the renin-angiotensin system within the kidney results in an increase in efferent glomerular arteriolar tone and a rise in glomerular capillary pressure, increased proteinuria and a greater risk for renal injury. Many of the coexisting cardiovascular risk factors associated with salt sensitivity may be explainable in part by the overactivity of the renin-angiotensin system.
Renal Reserve Is Normal in Patients with Dilative Cardiomyopathy Waiting for Heart Transplantation
Authors: Frangiosa Annamaria , Spitali Lucia , Molino Daniela , Cirillo Eleonora , De Santo Luca , Marra Claudio , Maiello Ciro , De Vivo Fabrizio , Pascale Carmen , Favazzi Pietro , Di Leo Vito , De Santo Natale , Anastasio Pietro
Published: April 2003

Renal reserve was explored by means of an oral protein load (2 g/kg body weight) under the form of cooked red meat in a group of 9 patients with end-stage heart failure (ESHF), class III of the New York Heart Association receiving loop diuretics and angiotensin-converting enzyme (ACE) inhibitors, and in a group of 18 healthy controls (HC) matched for age, gender, and height under an identical dietary regimen providing 40 cal/kg per day, 1 g/kg body weight of protein per day, Na 120 mmol/day, and K 50 mmol/day. Baseline glomerular filtration rate averaged 109.5±9.89 ml/min×1.73 m2 in HC and 71.9±8.8 ml/min×1.73 m2 in ESHF. Renal plasma flow averaged 540±27 ml/min×1.73 m2 in HC and 235±47 ml/min×1.73 m2 in ESHF. The filtration fraction was significantly higher in ESHF (p<0.01). Renal reserve averaged 26.03±3.28 ml/min×1.73 m2 in HC and 27.2±7.12 ml/min×1.73 m2 (not significant). Renal reserve averaged 123.9±2.9% in HC and 137.3±6.68% in ESHF (not significant). The filtration capacity was significantly higher in HC (p<0.001). The data point to a normalcy of renal reserve in ESHF which may depend on the chronic use of ACE inhibitors.
Mathematical Model to Estimate Risk of Calcium-Containing Renal Stones
Authors: Pietrzyk Robert A. , Feiveson Alan H. , Whitson Peggy A.
Published: April 2003

Background/Aims: Astronauts exposed to microgravity during the course of spaceflight undergo physiologic changes that alter the urinary environment so as to increase the risk of renal stone formation. This study was undertaken to identify a simple method with which to evaluate the potential risk of renal stone development during spaceflight. Method: We used a large database of urinary risk factors obtained from 323 astronauts before and after spaceflight to generate a mathematical model with which to predict the urinary supersaturation of calcium stone forming salts. Result: This model, which involves the fewest possible analytical variables (urinary calcium, citrate, oxalate, phosphorus, and total volume), reliably and accurately predicted the urinary supersaturation of the calcium stone forming salts when compared to results obtained from a group of 6 astronauts who collected urine during flight. Conclusions: The use of this model will simplify both routine medical monitoring during spaceflight as well as the evaluation of countermeasures designed to minimize renal stone development. This model also can be used for Earth-based applications in which access to analytical resources is limited.
The Balance between Glucocorticoids and Insulin Regulates Muscle Proteolysis via the Ubiquitin-Proteasome Pathway
Authors: Bailey James , Wang Xiaonan , Price S.
Published: April 2003

In uremia, accelerated muscle protein degradation results from activation of the ATP-ubiquitin proteasome proteolytic pathway. Like uremia, other conditions (e.g., acidosis and diabetes) activate this pathway in rat muscles and are associated with excess glucocorticoids (GC) and impaired insulin action. To define the stimuli responsible for muscle wasting in IDDM, the roles of glucocorticoids, insulinopenia and acidosis in streptozotocin (STZ) – induced diabetes were studied. Proteolysis in isolated epitrochlearis muscles from acutely (3d) diabetic rats was 52% higher than pair-fed, sham-injected rats; this increase was eliminated by an inhibitor of the proteasome or by blocking ATP synthesis. In muscles of STZ-diabetic rats, the levels of ubiquitin-conjugated proteins and mRNAs encoding ubiquitin, the ubiquitin-carrier protein, E214k and the C3, C5 and C9 proteasome subunits were increased. Transcription of ubiquitin and C3 proteasome subunit genes in muscle was also increased by IDDM. Oral NaHCO3 eliminated acidemia but did not prevent accelerated muscle proteolysis. Corticosterone excretion was higher in IDDM rats and adrenalectomy (ADX) prevented these catabolic responses; physiologic doses of glucorcoticoids restored the excessive protein catabolism in ADX-STZ rats. Giving IDDM rats replacement insulin also normalized protein degradation in muscles. In conclusion, reduced insulin together with physiologic levels of glucocorticoids activate the ubiquitin-proteasome pathway by a mechanism that includes enhancing ubiquitin conjugation and proteolysis by the proteasome. The balance between these stimuli could regulate muscle proteolysis in uremia.
Genesis of Atherosclerosis in Uremic Patients
Authors: Drüeke Tilman
Published: April 2003

Atherosclerosis significantly contributes to the high incidence of cardiovascular complications and death of uremic patients. Whereas some of the mechanisms that are being discussed in the atherogenesis of chronic renal failure are well established, many others remain hypothetical at present. One of the main reasons is that no long-term, well-controlled studies are available in this area which would have systematically tested the importance of factors such as high blood pressure, via the use of antihypertensive drugs, or disturbances of lipoprotein metabolism, via the use of lipid-lowering medications. Current clinical practice as to the use of the latter has been extensively reviewed in a recent meta-analysis by Massy et al. [69]. The majority of studies have been limited to relating hemodynamic or metabolic parameters to parameters of ischemia. Controlled long-term studies are required to reach valid conclusions on the implications of the numerous factors which theoretically may play a role in the atherosclerotic complications of chronic renal failure patients.
Molecular Genetics of Homocysteine Metabolism
Authors: Födinger Manuela , Buchmayer Heidi , Sunder-Plassmann Gere
Published: April 2003

Recent genetic studies have led to the characterization of molecular determinants contributing to the pathogenesis of hyperhomocysteinemia. In this article we summarize the current insights into the molecular genetics of severe, moderate and mild hyperhomocysteinemia. We will consider deficiencies of the trans-sulfuration enzyme cystathionine β-synthase (gene symbol: CBS), and the disturbances of the remethylation enzymes 5,10-methylenetetrahydrofolate reductase (gene symbol: MTHFR), methionine synthase (gene symbol: MTR), and the recently identified methionine synthase reductase (gene symbol: MTRR). Furthermore, we will focus on clinically important genetic polymorphisms which are highly prevalent and thus of potential general interest.
Regulation of Appetite in Chronic Renal Failure
Authors: Bergström Jonas
Published: April 2003

Anorexia, nausea and vomiting in patients with severe renal failure may cause or contribute to development of protein-energy malnutrition, which is associated with increased morbidity and mortality. However, the specific mechanisms that cause appetite suppression in uremia are poorly understood. This review summarizes the general mechanisms by which appetite is regulated. Various factors are discussed that may potentially be involved in appetite suppression in chronic renal failure.
Intradialytic Parenteral Nutrition in Malnourished Hemodialysis Patients. Review of the Literature
Authors: Mortelmans Anna , Vanholder Raymond
Published: April 2003

Malnutrition is a frequent problem of patients on intermittent hemodialysis and is associated with increased morbidity and mortality. Intradialytic parenteral nutrition (IDPN), i.e. intravenous supplementation of mixtures of glucose, amino acids and/or lipids during the hemodialysis session, is one of the therapeutic measures that are applied to correct this malnutrition. To our knowledge only few long-term clinical studies have been undertaken, evaluating the effect of intravenous calorie administration in hemodialysis. Most studies were carried out over a relatively short observation period in small study populations; in several of these studies, no measures were taken to prevent losses of nutrients in the dialysate; adequate control groups are often missing. The authors review the current available literature and conclude that IDPN might have a significant beneficial effect on the nutritional status in malnourished hemodialysis populations.
Transcriptional and Post-Transcriptional Regulation of PTH Gene Expression by Vitamin D, Calcium and Phosphate
Authors: Sela-Brown Alin , Naveh-Many Tally , Silver Justin
Published: April 2003

1,25(OH)2D3 the biologically active metabolite of vitamin D is synthesized in the renal proximal tubules from the hepatic metabolite 25 (OH)D. Lack of 1,25(OH)2D3 is relevant to the pathogenesis of secondary hyperparathyroidism, and 1,25(OH)2D3 itself is used effectively in the management of renal failure patients to prevent secondary hyperparathyroidism. The scientific basis of this therapy is the finding that 1,25(OH)2D3 potently decreases PTH gene transcription both in vitro and in vivo.
Bioelectrical Impedance Analysis in Dialysis Patients
Authors: Pupim Lara B. , Kent Pamela , Ikizler T. Alp
Published: April 2003

Identification of malnutrition is imperative in chronic dialysis patients. Bioelectrical impedance (BIA) is a noninvasive method to measure body composition and estimate total body water (TBW), lean body mass (LBM) and body cell mass (BCM). Studies suggest BIA has good reliability as compared to other accepted methods of body composition analysis. Preliminary data also suggest that BIA-derived parameters (reactance and phase angle) predict clinical outcome in chronic hemodialysis patients. Overall, BIA is a promising nutritional assessment tool to monitor health status, long-term follow-up, tailor nutrition support, and detect early subtle losses of LBM in chronic dialysis patients.