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41.
Treatment of motoneuron degeneration by intracerebroventricular delivery of VEGF in a rat model of ALS 总被引:18,自引:0,他引:18
Storkebaum E Lambrechts D Dewerchin M Moreno-Murciano MP Appelmans S Oh H Van Damme P Rutten B Man WY De Mol M Wyns S Manka D Vermeulen K Van Den Bosch L Mertens N Schmitz C Robberecht W Conway EM Collen D Moons L Carmeliet P 《Nature neuroscience》2005,8(1):85-92
Neurotrophin treatment has so far failed to prolong the survival of individuals affected with amyotrophic lateral sclerosis (ALS), an incurable motoneuron degenerative disorder. Here we show that intracerebroventricular (i.c.v.) delivery of recombinant vascular endothelial growth factor (Vegf) in a SOD1(G93A) rat model of ALS delays onset of paralysis by 17 d, improves motor performance and prolongs survival by 22 d, representing the largest effects in animal models of ALS achieved by protein delivery. By protecting cervical motoneurons, i.c.v. delivery of Vegf is particularly effective in rats with the most severe form of ALS with forelimb onset. Vegf has direct neuroprotective effects on motoneurons in vivo, because neuronal expression of a transgene expressing the Vegf receptor prolongs the survival of SOD1(G93A) mice. On i.c.v. delivery, Vegf is anterogradely transported and preserves neuromuscular junctions in SOD1(G93A) rats. Our findings in preclinical rodent models of ALS may have implications for treatment of neurodegenerative disease in general. 相似文献
42.
Although investigators have demonstrated that neocartilage can be constituted in a predetermined shape and in complex three-dimensional structures, such as a human ear, by using cell transplantation on polymer constructs, many unsolved problems still remain. The crucial issues for auricular tissue engineering consisted of optimal cell culture environment, choice of polymers, behavior of chondrocytes, study of cell-polymer constructs in an acceptable animal model, and long-term structural integrity. Here we describe our tissue engineering approaches for auricular reconstruction including auricular scaffold fabrication, in vitro chondrogenesis, in vivo immunocompromized xenograft and immunocompetent autologous animal models, and long-term follow-up. Though many current obstacles regarding auricular tissue engineering still exist, we demonstrate techniques of auricular scaffold fabrication with promising in vitro and in vivo neocartilage formation, optimal selection and application of animal models, and, to the best of our knowledge, the first report of different biodegradable biomaterial trials and the longest in vivo results (10 months) for auricular tissue engineering. 相似文献
43.
Dynamic patterns of expression of BMP isoforms 2, 4, 5, 6, and 7 during chicken heart development 总被引:2,自引:0,他引:2
Somi S Buffing AA Moorman AF Van Den Hoff MJ 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2004,279(1):636-651
Bone morphogentic proteins (BMPs) play an important role in cardiac development. Using an in vitro explant analysis, we show that BMPs are crucial for myocardium formation. As a first approach to identify which BMP may be involved in myocardium formation in intra- and extracardiac mesenchyme in vivo, a survey of the expression patterns of BMP2, -4, -5, -6, and -7 mRNA is prepared by in situ hybridization in chicken embryonic hearts from HH5 to 44. During recruitment of mesodermal cells to the outflow tract myocardium (HH10-23), BMP2, -4, -5, and -7 mRNA are expressed in the distal myocardial border and the flanking mesenchyme. After completion, BMP2 and -4 mRNA become restricted to the mesenchyme and BMP5 and -7 mRNA to the myocardium. At the venous pole, BMP2, -5, and -7 mRNA are expressed in the distal myocardial border of the caval vein, while BMP2, -5, -6, and -7 mRNA are expressed in the distal myocardium around the pulmonary vein. BMP4 mRNA is expressed in the adjacent mesenchyme at both sides. During muscularization of the atrioventricular cushions and the tricuspid valve, the cardiomyocytes that protrude into the mesenchyme express BMP2, -4, -5, and -7 mRNA, whereas BMP6 mRNA is expressed in the cushion mesenchyme. The myocardial protrusions formed in the mesenchymal proximal outlet septum express BMP4, -5, and -7 mRNA, while BMP2 and -6 mRNA are expressed in the mesenchyme. The spatiotemporal expression patterns of these BMPs in relation to myocardium formation at the distal ends and within the heart suggest a role for BMPs in myocardium formation. During delamination of the valves, BMP4 and -6 mRNA are expressed at the ventricular side of the forming mitral valve, BMP4 mRNA at the ventricular side of the forming tricuspid valve, and BMP2, -4, and -6 mRNA at the vascular side of the forming semilunar valves. 相似文献
44.
Genomic imprinting in mammals marks the two parental alleles resulting in differential gene expression. Imprinted loci are characterized by distinct epigenetic modifications such as differential DNA methylation and asynchronous replication timing. To determine the role of DNA methylation in replication timing of imprinted loci, we analyzed replication timing in Dnmt1- and Dnmt3L-deficient embryonic stem (ES) cells, which lack differential DNA methylation and imprinted gene expression. Asynchronous replication is maintained in these ES cells, indicating that asynchronous replication is parent-specific without the requirement for differential DNA methylation. Imprinting centers are required for regional control of imprinted gene expression. Analysis of replication fork movement and three-dimensional RNA and DNA fluorescent in situ hybridization (FISH) analysis of the Igf2-H19 locus in various cell types indicate that the Igf2-H19 imprinting center differentially regulates replication timing of nearby replicons and subnuclear localization. Based on these observations, we suggest a model in which cis elements containing nonmethylation imprints are responsible for the movement of parental imprinted loci to distinct nuclear compartments with different replication characteristics resulting in asynchronous replication timing. 相似文献
45.
Information technology (IT), long taken for granted in commercial settings, is now being utilized for healthcare applications. Medical imaging has lagged comparatively due to the extremely vast data content of each frame; thus, the requirement for expensive high-end components. Further, IT in radiology has evolved from two distinctly separate camps—information systems, known as RIS (radiology information systems) and PACS (picture archiving and communications systems). Both RIS and PACS applications have migrated to the PC environment, enabling cost-effective implementation, but from two backgrounds: RIS from vendors using conventional information systems platforms and products, and PACS from radiographic film and modality vendors. The radiology department at Texas Tech University has assembled a seamlessly integrated, enterprise-wide RIS/PACS/teleradiology intranet. The design criteria include user-friendliness, flexibility to respond to changing needs, and open modular architecture to assure interoperability, cost-effectiveness, and future-proofing of investment. Since no single venor could provide an integrated system meeting our specifications, we decided to assume the burden of constructing our own system. As the system integrator, we embrace open architecture, thus enabling the incorporation of industry-standard-compliant, COTS (commercially off the shelf) products as modules. Microsoft Windows NT operating system, Visual C++ programming language, TCP/IP (transmission control protocol/internetworking protocol), relational SQL (structured query language) database, ODBC (open database connectivity), HL-7 (health level seven) and DICOM (digital imaging and communications in medicine) interfaces are utilized. The usage of COTS components reduces the cost to very affordable levels. With this approach, any module in our system can be replaced when outmoded, without affecting other modules in our system, making it truly future-proof. Construction and evolution of our system (TECHRAD) is reviewed. 相似文献
46.
Guarner J Jernigan JA Shieh WJ Tatti K Flannagan LM Stephens DS Popovic T Ashford DA Perkins BA Zaki SR;Inhalational Anthrax Pathology Working Group 《The American journal of pathology》2003,163(2):701-709
During October and November 2001, public health authorities investigated 11 patients with inhalational anthrax related to a bioterrorism attack in the United States. Formalin-fixed samples from 8 patients were available for pathological and immunohistochemical (IHC) study using monoclonal antibodies against the Bacillus anthracis cell wall and capsule. Prominent serosanguinous pleural effusions and hemorrhagic mediastinitis were found in 5 patients who died. Pulmonary infiltrates seen on chest radiographs corresponded to intraalveolar edema and hyaline membranes. IHC assays demonstrated abundant intra- and extracellular bacilli, bacillary fragments, and granular antigen-staining in mediastinal lymph nodes, surrounding soft tissues, and pleura. IHC staining in lung, liver, spleen, and intestine was present primarily inside blood vessels and sinusoids. Gram's staining of tissues was not consistently positive. In 3 surviving patients, IHC of pleural samples demonstrated abundant granular antigen-staining and rare bacilli while transbronchial biopsies showed granular antigen-staining in interstitial cells. In surviving patients, bacilli were not observed with gram's stains. Pathological and IHC studies of patients who died of bioterrorism-related inhalational anthrax confirmed the route of infection. IHC was indispensable for diagnosis of surviving anthrax cases. The presence of B. anthracis antigens in the pleurae could explain the prominent and persistent hemorrhagic pleural effusions. 相似文献
47.
Germinal mosaicism increases the recurrence risk for ''new'' Duchenne muscular dystrophy mutations. 总被引:18,自引:6,他引:18
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E Bakker H Veenema J T Den Dunnen C van Broeckhoven P M Grootscholten E J Bonten G J van Ommen P L Pearson 《Journal of medical genetics》1989,26(9):553-559
In 288 Dutch and Belgian Duchenne and Becker muscular dystrophy families, the parental origin of 41 new deletion or duplication mutations was determined. Twenty seven of the new mutations occurred in the maternal X chromosome and nine in the grandmaternal and five in the grandpaternal X chromosome. The grandparental data are compatible with equal mutation rates for DMD in male and female X chromosomes. New mutations were defined by their presence in one or more progeny and absence in the lymphocytes of the mother or the grandparents. In one family a fraction of the maternal lymphocytes was found to carry the mutation, suggesting somatic mosaicism. In six cases out of 41, the mutation was transmitted more than once by a parent in whom the mutation was absent in lymphocytes, suggesting gonadal mosaicism as the explanation for the multiple transmission. Using our data for the recurrence of the mutations among the total of at risk haplotypes transmitted, we arrive at a recurrence risk of 14% for the at risk haplotype. The observation of this high risk of germinal mosaicism is crucially important for all physicians counselling females in DMD families. Recently, germinal mosaicism has been observed also in a number of other X linked and autosomal disorders. The implications and appropriate diagnostic precautions are discussed. 相似文献
48.
Jean-Pierre Fryns Walter Bettens Herman Van Den Berghe James F. Reynolds 《American journal of medical genetics. Part A》1986,24(1):175-178
We report on an8-month-old girl with a de novo 5q/6q autosomal translocation with loss of the distal part of the long arm of chromosome 6 (6q23.3→6qter); clinical manifestations are peculiar craniofacial stigmata, truncal obesity and persisting hypotonia. The similarity with a previously reported patient with 6q interstitial deletion is discussed. 相似文献
49.
Koorengevel KM Beersma DG Den Boer JA Van Den Hoofdakker RH 《Journal of sleep research》2002,11(4):347-356
The majority of winter-type seasonal affective disorder (SAD) patients complain of hypersomnia and daytime drowsiness. As human sleep is regulated by the interaction of circadian, ultradian and homeostatic processes, sleep disturbances may be caused by either one of these factors. The present study focuses on homeostatic and ultradian aspects of sleep regulation in SAD. Sleep was recorded polysomnographically in seven SAD patients and matched controls subjected to a 120-h forced desynchrony protocol. In time isolation, subjects were exposed to six 20-h days, each comprising a 6.5-h period for sleep. Patients participated while being depressed, while remitted after light therapy and in summer. Controls were studied in winter and in summer. In each condition, the data of each subject were averaged across all recordings. Thus, the influence of the effects of the circadian pacemaker on sleep was excluded mathematically. The comparison of patients with controls and with themselves in the various conditions revealed no abnormalities in homeostatic parameters: sleep stage variables, relative power spectra and time courses of power in various frequency bands across the first three non-rapid eye movement-rapid eye movement (NREM-REM) cycles showed no differences. The data suggest that homeostatic processes are not involved in the disturbance of sleep in SAD. 相似文献
50.
Anne Uyttebroeck Penelope Brock Bert De Groote Marleen Renard Paola Dal Cin Herman Van Den Berghe Maria Casteels-Van Daele 《Cancer Genetics and Cytogenetics》1995,80(2):121-123
A boy aged 8 years, 10 months presented with refractory anemia. Bone marrow investigation revealed monolobular megakaryocytes. Cytogenetic analysis showed a clonal abnormality: 46, XY, del(5)(q14q32). This is the youngest individual ever reported with this disorder. A year after diagnosis, while on treatment with human recombinant erythropoietin, the bone marrow showed an excess of blasts. No bone marrow donor could be found. Transformation to acute myelomonocytic leukemia occurred 3 months later. In spite of intensive chemotherapy, the child died of progressive disease with massive splenomegaly and jaundice. The case illustrates that the 5q- syndrome can occur de novo in children. The outcome in this child was poor, which may reflect a difference from the adult 5q- syndrome or may possibly be related to the erythropoietin the child received. 相似文献