bluuebunny/crossref_metadata_2025 huggingface dataset:
Chromosomal aberrations involving telomeres in BRCA1 deficient human and mouse cell lines
Authors: Al-Wahiby S. , Slijepcevic P.
Published: May 2005

Cells defective in BRCA1 show genomic instability as evidenced by increased radiosensitivity, the presence of chromosomal abnormalities and the loss of heterozygosity at many loci. Reported chromosomal abnormalities in BRCA1 deficient cells include dicentric chromosomes. Dicentric chromosomes, in some cases, may arise as a result of end-to-end chromosome fusions, which represent signatures of telomere dysfunction. In this study we examined BRCA1 deficient human and mouse cells for the presence of chromosomal aberrations indicative of telomere dysfunction. We identified a lymphoblastoid cell line, GM14090, established from a BRCA1 carrier that showed elevated levels of dicentric chromosomes. Molecular cytogenetic analysis revealed that these dicentric chromosomes result from end-to-end chromosome fusions. The frequency of end-to-end chromosome fusions did not change after exposure of GM14090 cells to bleomycin but we observed elevated levels of chromosomal abnormalities involving interactions between DNA double strand breaks and uncapped telomeres in this cell line. We observed similar chromosomal abnormalities involving telomeres in the breast cancer cell line, HCC1937, homozygous for BRCA1 mutation. Finally, we analyzed mouse embryonic stem cells lacking functional Brca1 and observed the presence of telomere dysfunction following exposure of these cells to bleomycin. Our results reveal cytogenetic evidence of telomere dysfunction in BRCA1 deficient cells.
Chromosome evolution in fish: BrdU replication patterns demonstrate chromosome homeologies in two species of the genus Astyanax
Authors: Daniel-Silva M.F.Z. , Almeida-Toledo L.F.
Published: May 2005

A comparison of R-banding patterns obtained by 5-bromodeoxyuridine incorporation was made between the chromosomes of two fish species of the genus Astyanax (Characiformes: Tetragonopterinae), A. altiparanae with 2n = 50 chromosomes, and A. schubarti with 2n = 36 chromosomes. The two species present the highest and the lowest chromosome numbers found in this fish genus, respectively, for which the modal chromosome number is 50. R-band homeology was detected, involving eleven chromosomes of A. schubarti and seventeen chromosomes of A. altiparanae, indicating a close chromosomal relationship between the two species, in spite of their great difference in chromosome number. A chromosome fusion in the past history of the group was hypothesized as a possible cause of the discrepant chromosome numbers of the two species.
Characterization of G-banded chromosomes of a female saola (Pseudoryx nghetinhensis,2n = 50) and X chromosome i dentification by means of fluorescent in situ hybridization
Authors: Nguyen T.T. , Nguyen B.X. , Stranzinger G.
Published: May 2005

The saola (Pseudoryx nghetinhensis) is a newly discovered large mammal species, belongs to the subfamily Bovinae and is listed as being endangered. Due to the limitation of the material available, no cytogenetic studies have been carried out on this species. In the present study, preliminary cytogenetic analysis was undertaken on cultured female fibroblast cells to characterize the karyotype organization of saola. An examination of 120 Giemsa stained metaphases showed the diploid chromosome number of 2n = 50, including five bi-armed chromosome pairs. The distribution of constitutive heterochromatin in saola was studied. However, the variability in the size of C-bands was not significant on all the homologous chromosomes. The X chromosome pair, corresponding to the largest telocentric chromosomes, was identified by fluorescent in situ hybridization (FISH) using a bacterial artificial chromosome clone (BAC 0577G05, which maps to BTAXq25→q33). In comparison to the standard karyotype of cattle (ISCNDB 2000), a G-banded ideogram of saola (about 390 band level) was presented. This work, therefore, provided a basic insight into the karyotype organization of this endangered species and will be particularly useful to improve the understanding of differences of genomes between related species.
Lack of correspondence between CMA3-, Ag-positive signals and 28S rDNA loci in two Iberian minnows (Teleostei, Cyprinidae) evidenced by sequential banding
Authors: Gromicho M. , Ozouf-Costaz C. , Collares-Pereira M.J.
Published: May 2005

Despite the growing outcome of results that put doubt upon the reliability of silver (Ag) staining and chromomycin A3 (CMA3) fluorescent banding in the detection of major ribosomal gene sites (NORs), these methods have been widely used, especially in fishes. In order to clarify the previous patterns obtained with those techniques, we performed fluorescence in situ hybridisation (FISH) with 28S rDNA probe followed by sequential CMA3 and Ag staining in diploid non-hybrid males of the Squalius alburnoides complex and in Squalius pyrenaicus. The results from all the studied specimens revealed a lack of correlation between classical and molecular techniques. Not just some other regions besides NORs were stained with CMA3 and Ag, but also the majority of the 28S rDNA sites were not detected. Care should then be taken in considering CMA3- and Ag-stained sites as NORs since their accuracy for that purpose may not always correspond to the expectations.
Polymorphic karyotypes and sex chromosomes in the tufted deer (Elaphodus cephalophus): cytogenetic studies and analyses of sex chromosome-linked genes
Authors: Cao X. , Jiang H. , Zhang X.
Published: May 2005

Different diploid chromosome numbers have been reported for the tufted deer Elaphodus cephalophus (female, 2n = 46/47; male, 2n = 47/48) in earlier reports. In the present study, chromosomal analysis of seven tufted deer (5♂, 2♀) revealed that the karyotype of these animals contains 48 chromosomes, including a pair of large heteromorphic chromosomes in the male. C-banding revealed these chromosomes to be very rich in constitutive heterochromatin. Chromosome banding and PCR of sex chromosome-linked genes (SRY, ZFX, ZFY) performed on DOP-PCR products of single microdissected X and Y chromosomes confirmed that the large telocentric chromosome without secondary constriction is the X chromosome whereas the subtelocentric chromosome is the Y. The increased size of both, the X and Y chromosome, appears to be at least partially attributable to the presence of substantial amounts of heterochromatin.
Positional and functional characterisation of apoptosis related genes belonging to the BCL2 family in sheep
Authors: Lyahyai J. , Goldammer T. , Beattie A.E. , Zaragoza P. , Martín-Burriel I.
Published: May 2005

Apoptosis is a process whereby cells die in a controlled manner and it is involved in animal development, tissue homeostasis and a variety of diseases. The B-cell lymphoma 2 family proteins are central regulators of intracellular apoptotic signalling cascades. This work describes the isolation of cDNA and genomic fragments from five sheep BCL2 related genes: BCL2, BCL2L1, BCL2L2, BAX and MCL1. Transcript sequences showed a high homology with BCL2 related genes from other species. Three cattle BAC probes containing the homologous BCL2, BCL2L1 and BCL2L2 genes were identified and used for comparative FISH mapping in sheep. BCL2 was localised in OAR23q27, BCL2L1 in OAR13q22 and BCL2L2 in OAR7q15→q21. Intron polymorphisms were used for linkage mapping of BAX and MCL1, which were mapped on OAR14 and OAR1 respectively. Moreover, a BCL2L1 pseudogene was also identified and linkage mapped on OAR2. The expression of these genes was analysed in mammary gland, ovary, intestine and brain which are target tissues for sheep pathological processes where apoptosis is involved.
Assignment of non-informative turkey genetic markers through comparative approaches
Authors: Reed K.M. , Holm J. , Morisson M. , Leroux S. , Vignal A.
Published: May 2005

Molecular markers such as microsatellites, provide genetic signposts for navigating genomes. In general, genetic markers that are monomorphic or non-informative in mapping populations typically remain unmapped and as such are less likely to be included in future studies. The use of hybrid cell panels and in silico mapping via whole genome sequences allow for positional mapping of non-segregating markers. This study utilizes the INRA ChickRH6 whole-genome radiation hybrid panel and chicken whole-genome shotgun sequence to map microsatellite markers from the turkey (Meleagris gallopavo). Thirty-three of the 41 markers typed on the RH panel had significant linkage to at least one other marker and 83 of 100 sequences returned significant BLAST similarities. Positioning of these markers provides additional sequence tagged sites in the turkey genome and increases the potential use of these markers for future genetic studies.
Navigation-Assisted Construction of an External Ear Canal Using an Autogenous Foreskin Graft
Authors: Frölich K. , Kleinsasser N. , Rasp G. , Staudenmaier R.
Published: May 2005

Classic microtia is combined with external ear canal atresia and middle ear malformation. In order to evaluate whether an operation to improve hearing ability and the use of computer-assisted surgery are indicated, preoperative high-resolution navigation CT is mandatory. We combined atresia surgery and tympanoplasty with auricular reconstruction in the case of an 8-year-old boy with bilateral microtia, aural atresia and malformation of the middle ear. After creating an auricle framework with rib cartilage and transplanting it under the skin of the mastoid plane, we shifted it forward in the second step, and the new auditory canal was drilled under computer-assisted navigation and facial nerve monitoring. In the same operation, tympanoplasty was accomplished, and a silastic cylinder, wrapped into pieces of rib cartilage, was inserted into the constructed canal and removed 2 months later. For lining the new auditory canal, we used the patient’s prepuce, harvested by elective circumcision.
Serotonin Transporter Gene Polymorphism and Personality Traits in a Korean Population
Authors: Kim Se Joo , Kim Young Shin , Choi Nak Kyung , Hong Hyun Joo , Lee Hong Shick , Kim Chan-Hyung
Published: May 2005

Recently, there has been growing enthusiasm for exploring biological approaches to personality, especially in the area of genetic research into the identification of those genes responsible for particular personality traits. The aim of this study was to investigate the association between the serotonin transporter-linked promoter region (5-HTTLPR) polymorphism and personality traits. We recruited 211 unrelated, normal subjects. The Korean version of the Temperament and Character Inventory (TCI) was used to assess certain personality traits. From blood samples taken from the subjects, DNA was isolated using standard techniques and the 5-HTTLPR polymorphism was genotyped by means of polymerase chain reaction and electrophoresis. We classified the subject into the s/s, s/l, and l/l groups according to their genotype. The differences in the temperament factors of the TCI between group S (s/s genotype) and group L (s/l + l/l genotype) were assessed, after the inclusion of gender and age as covariates in the analysis of variance. After controlling for gender and age, there were no associations between the harm avoidance, novelty seeking, and reward dependence scores and the genotypes. However, the persistence score of group S was significantly higher than that of group L. Our results suggest that the 5-HTTLPR polymorphism may be associated with the persistence score of the TCI in a normal Korean population.
Isolation-Induced Changes in Ultrasonic Vocalization, Fear-Potentiated Startle and Prepulse Inhibition in Rats
Authors: Nunes Mamede Rosa Maria Luiza , Nobre Manoel Jorge , Ribeiro Oliveira Amanda , Brandão Marcus Lira
Published: May 2005

Isolation causes important changes in the behavioral reactivity of rats to environmental stimuli. These changes include deficit in sensorimotor gating and altered fear-like responses to aversive stimuli. Measures of ultrasound vocalizations at 20–22 kHz when rats are exposed to threatening conditions, such as novelty, have been taken as a good measure of fear. The fear-potentiated startle to loud sounds and the prepulse inhibition tests have been considered reliable indicators of anxiety and attention impairments, respectively. Rats reared under conditions of isolation from weaning display clear deficits in prepulse inhibition. Taking into account that housing condition changes the emotional state of the animals, we evaluated in this work the performance of rats in the fear-potentiated startle test, prepulse inhibition and emission of ultrasound vocalizations to novelty when isolated for 10 days and after resocialization for 1 week in comparison to grouped rats. Isolated rats showed greater reactivity to loud sounds in the fear-potentiated startle test than grouped animals. They also emitted less ultrasound vocalizations at 20–22 kHz than grouped animals when exposed to a novel environment. In contrast to the well-known deficit in prepulse inhibition displayed by isolation-reared animals, in the present study isolation for 10 days caused a significant increase in prepulse inhibition. Resocialization was not able to counteract the effects of isolation in all three tests. The results suggest that the emotional state of the animals is altered by 10 days of isolation; they do not vocalize characteristically as grouped rats when submitted to novelty; unconditioned responses to loud sounds are enhanced and increased prepulse inhibition is shown rather than a deficit as largely documented in studies with isolation-reared animals. It is suggested that the assessment of the emotional state of the animals is a prerequisite in the evaluation of prepulse inhibition. The level of defensive reactivity displayed by isolated animals is crucial for the functioning of sensory gating and, by extension, to the expression of prepulse inhibition.
Automated Frequency Analysis of Synchronous and Diffuse Sleep Spindles
Authors: Huupponen Eero , Saastamoinen Antti , Niemi Jukka , Virkkala Jussi , Hasan Joel , Värri Alpo , Himanen Sari-Leena
Published: May 2005

Background: Sleep spindles have different properties in different localizations in the cortex. Objectives: First main objective was to develop an amplitude-independent multi-channel spindle detection method. Secondly the method was applied to study the anteroposterior frequency differences of pure synchronous (visible bilaterally, either frontopolarly or centrally) and diffuse (visible bilaterally both frontopolarly and centrally) sleep spindles. Methods: A previously presented spindle detector based on the fuzzy reasoning principle and a level detector were combined to form a multi-channel spindle detector. Results: The spindle detector had a 76.17% true positive rate and 0.93% false-positive rate. Pure central spindles were faster and pure frontal spindles were slower than diffuse spindles measured simultaneously from both locations. Conclusions: The study of frequency relations of spindles might give new information about thalamocortical sleep spindle generating mechanisms.
Cerebral Blood Flow during Vagus Nerve Stimulation – a Transcranial Doppler Study
Authors: Neu Peter , Heuser Isabella , Bajbouj Malek
Published: May 2005

Background and Objectives: Vagus nerve stimulation (VNS) is an approved treatment of partial onset seizures and has recently shown antidepressant effects in patients with treatment-resistant depression. This study was conducted to investigate whether acute VNS has an influence on cerebral blood flow (CBF) in humans. Methods: This investigation was designed as an add-on study. In 10 patients with an implanted stimulator who participated in a multicenter clinical trial to evaluate the efficacy of VNS in depression, CBF was investigated by functional transcranial Doppler at baseline (before the stimulator was turned on for the first time) and during stimulation with three different stimulation intensities in a randomized order. Results: Immediately after every increase of the current, CBF velocity showed a nonsignificant increase. Otherwise, no change of CBF above standard deviation could be registered. Conclusion: Acute VNS does not have an influence on CBF velocity in depressive patients.
Polymorphisms in the Serotonin Transporter Gene and Their Relationship to Two Temperamental Traits Measured by the Formal Characteristics of Behavior-Temperament Inventory: Activity and Emotional Reactivity
Authors: Dragan Wojciech Ł. , Oniszczenko Włodzimierz
Published: May 2005

Results obtained in earlier studies indicate that 5-HTT gene polymorphisms may have a certain impact on individual differences with respect to temperamental traits. The aim of our study was to determine whether the occurrence of various alleles of the serotonin transporter gene is related to the variability of two temperamental traits postulated in the Regulative Theory of Temperament (RTT) – activity and emotional reactivity. We have demonstrated that the 5-HTTLPR polymorphism is associated with one of the RTT temperamental traits – activity. Neither the relationship between the regulatory region polymorphism and emotional reactivity nor the association between the intron 2 VNTR polymorphism and the temperamental traits under study has been confirmed.
Specificity of SLC26A4 Mutations in the Pathogenesis of Inner Ear Malformations
Authors: Wu Chen-Chi , Chen Pei-Jer , Hsu Chuan-Jen
Published: May 2005

The traditional hypothesis concerning the pathogenesis of inner ear malformations holds that various types of malformations represent different stages of developmental arrest during embryogenesis. In order to verify this hypothesis, we surveyed mutations in the SLC26A4(PDS) gene, which were documented to cause enlarged vestibular aqueduct (EVA) and Mondini’s dysplasia (incomplete partition of the cochlea), in 35 families with various types of inner ear malformations. In 25 families, the probands showed EVA or Mondini’s dysplasia as the main temporal bone abnormalities, whereas the probands in the remaining 10 families revealed other types of malformations. In total, 7 mutated SLC26A4 alleles, including 6 missense mutations (A372V, A387V, T410M, S448L, T721M, and H723R) and 1 splice site mutation (IVS7-2A→G), were detected. All mutated alleles segregated the malformations of EVA and Mondini’s dysplasia, whereas no mutated alleles were found in the 10 probands with other types of malformations. SLC26A4 mutations were found in 22 of the 25 probands with EVA or Mondini’s dysplasia, indicating that these might be specific to the development of Mondini’s dysplasia and EVA. It is inferred that the pathogenetic mechanisms of the various malformations essentially differ, although their radiological findings appear to follow a continuum of morphological changes.
Experiential Anomalies and Self-Centrality in Schizophrenia
Authors: Raballo Andrea , Maggini Carlo
Published: May 2005

Background: Contemporary psychopathological research has shown that some qualitative anomalies of the first-person experiential givenness qualify the subjective experience of schizophrenia. Such essential clinical features of schizophrenia have recently been condensed into 7 phenomenologically coherent clusters derived from the Bonn Scale for the Assessment of Basic Symptoms (BSABS). The experimental intent of this study was to test whether subapophanic self-centrality (i.e. a protopathic nondelusional form of intersubjective spatial disattunement) empowers the discriminant capacity of such a set of subjective experiential disturbances among different diagnostic groups. Method: Three comparably sized samples of outpatients with schizophrenia, obsessive-compulsive or mood disorders were examined with the BSABS. Logistic regression analysis was performed with diagnosis as the outcome variable. Results: Elevated scores in self-perceived cognitive disorders and abnormal self-centrality were associated with DSM-IV diagnosis of schizophrenia. Self-centrality increased the discriminant capacity of the 7 designed a priori dimensions. Conclusions: These findings confirm the previously reported aggregation of some subtle qualitative alterations of subjective experience in schizophrenia, and suggest that a careful consideration of autocentric disturbances of intersubjectivity might enrich current heuristics on schizophrenic experiential vulnerability.
Delusional Mood and Delusional Perception – A Phenomenological Analysis
Authors: Fuchs Thomas
Published: May 2005

In the initial stages of schizophrenia, the environment as perceived by the patient changes into a puzzling, mysterious and stage-like scenery. At the same time, objects or persons may gain an overwhelming physiognomic expression and may even fuse with the patient’s body. The paper explains these different alterations using Husserl’s concept of intentional perception on the one hand, and Merleau-Ponty’s concept of embodied perception on the other hand. The first may also be understood as describing the intersubjective constitution of reality through common concepts which structure intentional perception. The latter points to the embodiment of the perceiving subject and uncovers our intimate connection with the world mediated by the lived body. Thus, in each perception, an active, intentional or ‘gnostic’ component and a bodily, ‘pathic’ component work together. On this basis, the alteration of schizophrenic perception in delusional mood may be described as a paralysis of intentionality, or of the ‘gnostic’ component of perception. The synthetic and sense-bestowing processes effective in perception are seriously disturbed. On the other hand, as a result of the disturbance of intentional perception, physiognomic and expressive properties are set free within the perceptual field. The ‘pathic’ component of perception becomes independent. Thus, the intersubjective constitution of reality is replaced by idiosyncratic meanings and qualities of perception, leading finally into delusional perception.
The Long-Term Outcome in Two Females with Autism Spectrum Disorder
Authors: Bölte Sven , Bosch Gerhard
Published: May 2005

We describe the results of a long-term follow-up examination of two adult females diagnosed exhibiting an autism spectrum disorder in childhood. Over four decades after the initial diagnosis made by Gerhard Bosch, besides Leo Kanner and Hans Asperger, one of the first clinicians to describe cases of autistic behavior, the individuals had largely different psychiatric outcomes. Despite the fact that both females continuously showed definite autistic traits, one woman exhibited a generalized anxiety disorder, while the other was predominantly characterized by schizoaffective symptoms. The trajectories of the two cases are discussed in the light of research on possible associations and overlaps between autism spectrum disorders, psychosis and anxiety disorders. It is suggested that adult outcome studies in autism should consider a broader range of comorbidity.
‘Internet Delusions’: A Case Series and Theoretical Integration
Authors: Bell Vaughan , Grech Ethan , Maiden Cara , Halligan Peter W. , Ellis Hadyn D.
Published: May 2005

Background: Delusions involving the internet have been reported as examples of the influence of cultural innovations on delusion formation, although there has been some debate as to whether such innovations simply affect surface content, or whether they have more substantial clinical or psychopathological implications. Sampling and Methods: Four cases of patients with delusions involving the internet were identified following a general request to local consultant psychiatrists for referrals. Results: The internet had a specific effect on aetiology in one case, and knowledge of the internet seemed to constrain the type of delusion formed in two others. The presence of an internet-related delusion in the final case was used to frame a successful clinical intervention based on the ‘collaborative empiricism’ method, using cognitive behavioural therapy and collaborative use of the internet to resolve the delusional belief. Conclusions: Cultural technical innovations may have specific influences on the form, origin and content of delusional beliefs. For some patients the presence of internet-themed delusions may be a good prognostic indicator since, given the rich sources of information available, they may be well suited to treatment with cognitive behavioural therapy.
Interpersonal Dependency in Suicide Attempters
Authors: Nuns Nathalie , Loas Gwenolé
Published: May 2005

Background: A high level of interpersonal dependency (IPD) has been reported in suicide attempters, which might be explained by depression levels as well as the high rate of female suicide attempters. Methods: 63 suicide attempters and 63 non-suicide attempters were recruited from a nonpsychiatric sample. The control subjects were individually matched to the patients for gender, age and educational status. The subjects filled out the Beck Depression Inventory and the Interpersonal Dependency Inventory (IDI). Analysis of covariance was performed to control the depression level. Results: Suicide attempters had significantly higher scores on the IDI than non-suicide attempters. Conclusion: A high level of IPD is related to suicide risk independently of depression. Limitation: only a prospective study could test the hypothesis that a high level of IPD predisposes an individual to commit suicide. Clinical relevance: IPD must be detected in subjects at risk of suicide.
Inhibiting Long-Chain Fatty Acyl CoA Synthetase Does Not Increase Agonist-Induced Release of Arachidonate Metabolites from Human Endothelial Cells
Authors: Weis Margaret T. , Brady Monica , Moore Mike , Crumley Jason , Stallone John N.
Published: May 2005

Background: Triacsin C, a fatty acid analog, inhibits endothelial nitric oxide synthetase (eNOS) palmitoylation, increases nitric oxide synthesis and enhances methacholine-induced relaxation of vascular rings. The experiments presented here tested the hypothesis that triacsin C increases the synthesis of PGI2 and/or endothelial-derived hyperpolarizing factor. Methods: Long-chain fatty acyl CoA synthetase activity (LCFACoAS), agonist-induced prostacyclin synthesis and agonist-induced release of radioactivity in endothelial cells labeled with [3H]arachidonic acid were measured in the presence and absence of triacsin C. Results: Inhibition by triacsin C of palmitoyl CoA formation was significantly greater than inhibition of arachidonoyl CoA formation in solubilized endothelial cell preparations. While 24-hour triacsin C treatment significantly reduced basal 6-keto synthesis, it had no effect on agonist-stimulated synthesis. The release of arachidonic acid metabolites was examined in [3H]arachidonate-labeled cells. Triacsin C treatment had no effect on basal or vasopressin-, angiotensin-II-, bradykinin- or ionomycin-induced release of radioactivity, but significantly reduced release in response to isoproterenol or phenylephrine. Expression of neither immunoreactive eNOS nor immunoreactive inducible nitric oxide synthetase (iNOS) was changed by triacsin C treatment, but the fraction of immunoreactive eNOS in the cytoplasm of treated cells was significantly greater as compared to vehicle control cells. Phorbol myristoyl acetate or fenofibrate significantly increased in vitro LCFACoAS activity, and significantly decreased the nitrite/eNOS ratio. Conclusions: These data indicate that, while triacsin C can inhibit arachidonoyl CoA synthetase in endothelial cells, it does not increase the availability of endogenous substrate for basal or agonist-induced PGI2 synthesis, nor does it enhance release of arachidonic acid or its metabolites.
Reversal of Reciprocity Failure for UVR-Induced Cataract with Vitamin E
Authors: Ayala Marcelo N. , Söderberg Per G.
Published: May 2005

Purpose: The authors have previously described that the photochemical reciprocity law does not apply for ultraviolet radiation (UVR)-induced cataract. The aim of this study was to elucidate if failure of the reciprocity reverses with vitamin E (α-tocopherol) administration. Methods: Altogether, 80 rats were divided into one group fed α-tocopherol and one control group. For each group, half of rats were exposed to UVR for 5 min and the remaining rats for 15 min. Results: Lenses exposed to UVR for 5 min showed no difference in light scattering between α-tocopherol-treated and untreated groups. Lenses exposed to UVR for 15 min showed significant difference in light scattering between α-tocopherol-treated and untreated groups. Conclusions: Failure in exposure time-intensity reciprocity for UVR-induced cataract with exposures shorter than 30 min may be due to consumption of antioxidants in the lens.
The Human Nephron Filter: Toward a Continuously Functioning, Implantable Artificial Nephron System
Authors: Nissenson Allen R. , Ronco Claudio , Pergamit Gayle , Edelstein Martin , Watts Richard
Published: May 2005

Background: Nearly 900,000 patients worldwide have end-stage renal disease and require dialysis or kidney transplantation, and this number is expected to more than double by 2010, placing considerable stress on healthcare systems throughout the world. Despite the availability of these forms of renal replacement therapy for nearly four decades, mortality and morbidity is high and patients often have a poor quality of life. Methods: We have developed a human nephron filter (HNF) utilizing nanotechnology that would eventually make feasible a continuously functioning, implantable artificial kidney. The device consists of two membranes operating in series within one device cartridge. The first membrane mimics the function of the glomerulus, while the second membrane mimics the function of the renal tubules. Findings: The device has been computer-modeled and operating 12 h/day, 7 days/week, the HNF provides the equivalent of 30 ml/min glomerular filtration rate (compared to half that amount for conventional thrice weekly hemodialysis). Conclusions: The HNF system, by eliminating dialysate and utilizing a novel membrane system created through applied nanotechnology may represent a breakthrough in renal replacement therapy based on the functioning of native kidneys. The enhanced solute removal and wearable design should substantially improve patient outcomes and quality of life.
Long-Term Evaluation of Basiliximab Induction Therapy in Live Donor Kidney Transplantation: A Five-Year Prospective Randomized Study
Authors: Sheashaa Hussein A. , Bakr Mohamed A. , Ismail Amany M. , Gheith Osama E. , El-dahshan Khalid F. , Sobh Mohamed A. , Ghoneim Mohamed A.
Published: May 2005

Background/Aims: The long-term evaluation of basiliximab induction therapy has not been addressed yet. We aim to evaluate its long-term effects in living related donor kidney transplantation. Methods: 100 adult recipients with their first kidney allograft were randomized into two treatment groups – one group received basiliximab and the second served as a control. All patients received a maintenance triple immunosuppressive therapy (steroids, cyclosporine microemulsion and azathioprine) and were closely followed for 5 years. Results: Basiliximab significantly reduced the proportion of patients who experienced an acute rejection in the first year (18/50) when compared to the control group (31/50) and in 5 years (27/50) when compared to (36/50) the controls. The cumulative steroid dose used throughout the study was significantly lower in the basiliximab group. The overall incidence of post-transplant complications was comparable between the two treatment groups. There was no significant difference in patients and graft survival; 5-year patient and graft survival were 100 and 86% for basiliximab, and 96 and 88% for the control group respectively. Conclusion: Although routine basiliximab induction significantly reduces the incidence of acute rejection, its beneficial long-term effects on graft function and patient and graft survival are not yet evident.
Effect of Nicotine on the Renal Microcirculation in Anesthetized Rats: A Potential for Medullary Hypoxic Injury?
Authors: Heyman Samuel N. , Goldfarb Marina , Rosenberger Christian , Shina Ahuva , Rosen Seymour
Published: May 2005

Background: Cigarette smoking has been associated with accelerated renal dysfunction among patients with chronic renal disease. Conceivably, repeated parenchymal hypoxic injury, induced by nicotine-related vasomotor changes, might contribute to the progression of renal failure in smokers. Methods: Renal blood flow and selective cortical and outer medullary blood flows were determined in anesthetized rats. Changes in total renal, cortical and medullary vascular resistance were calculated. Nicotine was repeatedly infused at rising doses (50–200 µg/kg) to intact (CTR) animals and to rats chronically administered with nicotine in their drinking water (NIC). In a complementary study, nicotine-treated and control rats were subjected to medullary hypoxic stress, induced by radiocontrast and indomethacin. Results: Chronic nicotine exposure led to lower baseline renal blood flow and creatinine clearance. Nicotine infusion induced a transient dose-dependent rise in blood pressure, renal blood flow and cortical flow, with a corresponding decline in renal vascular resistance and cortical resistance in both experimental groups. However, while medullary flow increased in CTR by up to 16 ± 6%, it remained unchanged or even somewhat declined in the NIC group. Calculated medullary resistance reciprocally declined in CTR while it rose in the NIC group (p < 0.001). In animals subjected to radiocontrast and indomethacin, nicotine intensified renal dysfunction, associated with focal medullary hypoxic damage. Conclusions: Chronic exposure to nicotine selectively compromises the outer medullary microcirculation, blunting a local vasodilatory response to acute nicotine administration. Repeated acute-on-chronic exposure to nicotine may predispose to hypoxic medullary injury.
Genitourinary Anomalies in Mowat-Wilson Syndrome with Deletion/Mutation in the Zinc Finger Homeo Box 1B Gene (ZFHX1B)
Authors: Garavelli L. , Cerruti-Mainardi P. , Virdis R. , Pedori S. , Pastore G. , Godi M. , Provera S. , Rauch A. , Zweier C. , Zollino M. , Banchini G. , Longo N. , Mowat D. , Neri G. , Bernasconi S.
Published: May 2005

Hypospadias, when the urethra opens on the ventral side of the penis, is a common malformation seen in about 3 per 1,000 male births. It is a complex disorder associated with genetic and environmental factors and can be part of genetic syndromes. Mowat-Wilson syndrome (MWS) is a multiple congenital anomaly syndrome characterized by a distinct facial phenotype, Hirschsprung disease, microcephaly and mental retardation. It is caused by mutations in the zinc finger homeo box 1B gene, ZFHX1B (SIP1). To date, 68 deletion/mutation-positive cases have been reported. Genitourinary anomalies are common in MWS. Here we report that hypospadias is common in males with this syndrome. In 39 patients where this information was available, hypospadias was present in 46% of patients (18/39). In the 3 Italian male cases reported here, hypospadias was always present. MWS should be considered by endocrinologists in patients with hypospadias associated with developmental delays/mental retardation, in particular in the presence of a distinct facial phenotype.
Effects of Prior Hypoxia Exposure, Endotoxin and Sleep State on Arousal Ability to Airway Obstruction in Piglets: Implications for Sudden Infant Death Syndrome
Authors: Voss L.J. , Bolton D.P.G. , Galland B.C. , Taylor B.J.
Published: May 2005

Background: Respiratory tract infections may be an important component in many deaths attributed to sudden infant death syndrome (SIDS), although the mechanism of involvement remains unclear. Objectives: The hypothesis was tested that prolonged hypoxia and a thermogenic state (simulating a fever due to respiratory tract infection) would impair respiratory responsiveness to airway obstruction during sleep. Methods: Thirty nine piglets aged 5–7 days were exposed to 24 h of moderate hypoxia and/or a low dose of endotoxin derived from Salmonella abortus equi. Responsiveness to complete and subtotal upper airway obstruction was tested during non-rapid eye movement (NREM) and rapid eye movement (REM) sleep. The end-point for airway obstruction tests was taken as the first protective response, either arousal or initiation of mouth breathing. Responsiveness was assessed as response time and response threshold (measured as respiratory effort, i.e. esophageal pressure swing). Results: All animals demonstrated a thermogenic state following endotoxin delivery (drop in ear temperature of 5.8 ± 0.2°C and a small but significant increase in rectal temperature). Response time to subtotal airway obstruction was reduced during the heat conserving phase of the fever (thermogenesis; 2.8 ± 0.5 s compared to 4.3 ± 0.7 s during pre-endotoxin tests), but markedly increased during the recovery period (20.3 ± 5.1 compared to 14.0 ± 2.5 s pre-endotoxin) in NREM sleep. Response threshold was not significantly affected by either endotoxin or hypoxia in NREM sleep. Respiratory responsiveness to subtotal obstruction was markedly reduced during REM sleep (response time 40.3 ± 10.9 s compared to 14.7 ± 2.2 s in NREM; response threshold –14.0 ± 1.3 mm Hg compared to –11.7 ± 1.0 mm Hg in NREM). Conclusions: This study has demonstrated in a neonatal animal model that respiratory responsiveness to airways obstruction is delayed during recovery from fever. The findings may have implications for the human infant recovering from a respiratory illness.
An Apolipoprotein(a) Peptide Delays Chylomicron Remnant Clearance and Increases Plasma Remnant Lipoproteins and Atherosclerosis In Vivo
Authors: Devlin Cecilia M. , Lee Sung-Joon , Kuriakose George , Spencer Craig , Becker Lev , Grosskopf Itamar , Ko Carol , Huang Li-Shin , Koschinsky Marlys L. , Cooper Allen D. , Tabas Ira
Published: May 2005

Objective—Humans with high expression of apolipoprotein(a) [apo(a)] and high plasma levels of lipoprotein(a) [Lp(a)] are at increased risk for atherosclerosis, but the mechanism is not known. We have previously shown that the KIV5–8domain of apo(a) has unique cell-surface binding properties, and naturally occurring fragments of apo(a) encompassing this domain are thought to be atherogenic in humans. To investigate the effect of KIV5–8on lipoprotein metabolism and atherosclerosis in vivo, we created several independent lines of liver-targeted KIV5–8transgenic mice.

Methods and Results—The transgenic mice have plasma apo(a) peptide concentrations that are similar to Lp(a) concentrations in humans at risk for coronary artery disease. Remarkably, the transgenic mice had a 2- to 4-fold increase in cholesterol-rich remnant lipoproteins (RLPs) when fed a cholesterol-rich diet, and a 5- to 20-fold increase in atherosclerosis lesion area in the aortic root. Using an in vivo clearance study, we found only slight differences in the triglyceride and apolipoprotein B secretion rates between the 2 groups of mice, suggesting an RLP clearance defect. Using an isolated perfused mouse liver system, we showed that transgenic livers had a slower rate of RLP removal, which was retarded further when KIV5–8, full-length apo(a), or Lp(a) were added to the perfusate. An apo(a) peptide that does not interact with cells, K(IV2)3, did not retard RLP removal, and low-density lipoprotein (LDL) had a much smaller effect than Lp(a).

Conclusions—We propose that high levels of apo(a)/Lp(a), perhaps acting via a specific cell-surface binding domain, inhibit hepatic clearance of remnants, leading to high plasma levels of RLPs and markedly enhanced atherosclerosis. We speculate that the KIV5–8region of apo(a) competes with one or more receptors for remnant clearance in the liver and that this process may represent one mechanism accounting for increased atherosclerosis in humans with high secretion levels of apo(a).
Regulation of Xanthine Oxidoreductase Protein Expression by Hydrogen Peroxide and Calcium
Authors: McNally J. Scott , Saxena Archana , Cai Hua , Dikalov Sergey , Harrison David G.
Published: May 2005

Objective—

We have previously demonstrated that endothelial xanthine oxidase (XO) levels are dependent on the NADPH oxidase. We postulated that H
2
O
2
may modulate the irreversible conversion of xanthine dehydrogenase (XDH) to XO and sought to examine mechanisms involved.

Methods and Results—

H
2
O
2
(100 μmol/L) decreased bovine aortic endothelial cell (BAEC) XDH protein expression, and metabolic labeling studies indicated that H
2
O
2
stimulated conversion of XDH to XO. The decline in XDH was mimicked by the reactive oxygen species (ROS) generating compounds SIN-1 and Menadione, as well as by stimulating BAECs with angiotensin II (200 nmol/L). BAPTA-AM prevented the decline in XDH by H
2
O
2
, indicating that it was calcium-dependent. In keeping with calcium acting downstream of H
2
O
2
, the calcium ionophore A23187 (1 μmol/L) caused XDH-to-XO conversion, and this was not prevented by the antioxidants. In addition, XDH-to-XO conversion was blocked by 2-APB and NO donors and induced by thapsigargin and M-3M3FBS, implicating phospholipase C and endoplasmic reticulum calcium stores in this process.

Conclusions—

Endothelial XO and XDH expression are strongly dependent on H
2
O
2
and calcium. Stimulation of XDH conversion to XO may represent a feed-forward mechanism whereby H
2
O
2
can stimulate further production of ROS.
Signaling of the Tissue Factor Coagulation Pathway in Angiogenesis and Cancer
Authors: Belting Mattias , Ahamed Jasimuddin , Ruf Wolfram
Published: May 2005

Activation of coagulation precedes or coincides with angiogenesis in wound healing and postischemic tissue regeneration. Advanced cancer is associated with a hypercoagulable state, and tissue factor expression by cancer cells has received widespread attention because of its significant contribution to the pathogenesis of cancer progression and metastasis. Our recent work demonstrates that tissue factor–mediated cellular signaling is relevant to cancer angiogenesis. Here we review the molecular mechanisms of tissue factor pathways in angiogenesis and tumorigenesis with emphasis on the intriguing role for tissue factor cytoplasmic domain signaling.
Effects of Recombinant Adenovirus-Mediated Uncoupling Protein 2 Overexpression on Endothelial Function and Apoptosis
Authors: Lee Ki-Up , Lee In Kyu , Han Jin , Song Dae-Kyu , Kim Yun Mi , Song Hai Sun , Kim Hyoun Sik , Lee Woo Je , Koh Eun Hee , Song Kee-Ho , Han Sung Min , Kim Min Seon , Park In-Sun , Park Joong-Yeol
Published: May 2005

Increased oxidative stress in vascular cells plays a key role in the development of endothelial dysfunction and atherosclerosis. Uncoupling protein 2 (UCP2) is an important regulator of intracellular reactive oxygen species (ROS) production. This study was undertaken to test the hypothesis that, UCP2 functions as an inhibitor of the atherosclerotic process in endothelial cells. Adenovirus-mediated UCP2 (Ad-UCP2) overexpression led to a significant increase in endothelial nitric oxide synthase (eNOS) and decrease in endothelin-1 mRNA expression in human aortic endothelial cells (HAECs). Moreover, UCP2 inhibited the increase in ROS production and NF-κB activation, and apoptosis of HAECs induced by lysophophatidylcholine (LPC) and linoleic acid. LPC and linoleic acid caused mitochondrial calcium accumulation and transient mitochondrial membrane hyperpolarization, which was followed by depolarization. UCP2 overexpression prevented these processes. In isolated rat aorta, Ad-UCP2 infection markedly improved impaired vascular relaxation induced by LPC. The data collectively suggest that UCP2, functions as a physiologic regulator of ROS generation in endothelial cells. Thus, measures to increase UCP2 expression in vascular endothelial cells may aid in preventing the development and progression of atherosclerosis in patients with metabolic syndrome.
HMG-CoA Reductase Inhibitors Inhibit Endothelial Exocytosis and Decrease Myocardial Infarct Size
Authors: Yamakuchi Munekazu , Greer James J.M. , Cameron Scott J. , Matsushita Kenji , Morrell Craig N. , Talbot-Fox Karen , Baldwin William M. , Lefer David J. , Lowenstein Charles J.
Published: May 2005

Three-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors protect the vasculature from inflammation and atherosclerosis by cholesterol dependent and cholesterol independent mechanisms. We hypothesized that HMG-CoA reductase inhibitors decrease exocytosis of Weibel-Palade bodies, endothelial cell granules whose contents promote thrombosis and vascular inflammation. We pretreated human aortic endothelial cells with simvastatin for 24 hours, then stimulated the cells with thrombin, and measured the amount of vWF released into the media. We then measured the effect of simvastatin on myocardial infarction in mice. Simvastatin decreased thrombin-stimulated Weibel-Palade body exocytosis by 89%. Simvastatin inhibited exocytosis in part by increasing synthesis of nitric oxide (NO), which S-nitrosylated N-ethylmaleimide sensitive factor (NSF), a critical regulator of exocytosis. Simvastatin treatment attenuated myocardial infarct size by 58% in wild-type but not eNOS knockout mice. Furthermore, simvastatin decreased endothelial exocytosis and neutrophil infiltration into ischemic-reperfused myocardium, which was mediated in part by P-selectin contained in Weibel-Palade bodies. However, simvastatin did not affect exocytosis and inflammation in myocardial infarcts of eNOS knockout mice. Inhibition of endothelial exocytosis is a novel mechanism by which HMG-CoA reductase inhibitors may reduce vascular inflammation, inhibit thrombosis, and protect the ischemic myocardium. These findings may explain part of the pleiotropic effects of statin therapy for patients with cardiovascular disease.
Laminar Shear Stress and 3′ Polyadenylation of eNOS mRNA
Authors: Weber Martina , Hagedorn Curt H. , Harrison David G. , Searles Charles D.
Published: May 2005

The 3′ poly(A) tail is important in messenger RNA stability and translational efficiency. In somatic tissues, 3′ polyadenylation of mRNAs has been thought to largely be a constitutively active process. We have reported that laminar shear stress causes a brief increase in endothelial nitric oxide synthase (eNOS) transcription, followed by a prolonged increase in eNOS mRNA stability. We sought to determine whether shear stress and other stimuli affected eNOS 3′ polyadenylation in endothelial cells. Under basal (static) conditions, eNOS mRNA possessed short 3′ poly(A) tails of <25 nt. In contrast, laminar shear stress increased expression of eNOS transcripts with long poly(A) tails. ENOS transcripts with longer poly(A) tails had prolonged half-lives (6 hours in static cells versus 18 hours in sheared cells). Polysome analysis revealed that eNOS mRNA from sheared cells was shifted into more translationally active polysome fractions compared with eNOS mRNA from static cells. Shear-induced lengthening of the eNOS 3′ poly(A) tail was the result of increased nuclear polyadenylation. Furthermore, hydrogen peroxide and HMG Co-A reductase inhibitors, other stimuli known to modulate eNOS expression posttranscriptionally, also induced eNOS 3′ poly(A) tail lengthening. These results support the concept that shear stress modulates eNOS mRNA stability and translation via increased 3′ polyadenylation. We suggest that mRNA 3′ polyadenylation is a posttranscriptional mechanism used by endothelial cells to regulate gene expression.