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1.
Heredity (Edinb) ; 119(6): 429-437, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28953268

RESUMO

The utilization of similar habitats by different species provides an ideal opportunity to identify genes underlying adaptation and acclimatization. Here, we analysed the gene expression of two closely related salamander species: Salamandra salamandra in Central Europe and Salamandra infraimmaculata in the Near East. These species inhabit similar habitat types: 'temporary ponds' and 'permanent streams' during larval development. We developed two species-specific gene expression microarrays, each targeting over 12 000 transcripts, including an overlapping subset of 8331 orthologues. Gene expression was examined for systematic differences between temporary ponds and permanent streams in larvae from both salamander species to establish gene sets and functions associated with these two habitat types. Only 20 orthologues were associated with a habitat in both species, but these orthologues did not show parallel expression patterns across species more than expected by chance. Functional annotation of a set of 106 genes with the highest effect size for a habitat suggested four putative gene function categories associated with a habitat in both species: cell proliferation, neural development, oxygen responses and muscle capacity. Among these high effect size genes was a single orthologue (14-3-3 protein zeta/YWHAZ) that was downregulated in temporary ponds in both species. The emergence of four gene function categories combined with a lack of parallel expression of orthologues (except 14-3-3 protein zeta) suggests that parallel habitat adaptation or acclimatization by larvae from S. salamandra and S. infraimmaculata to temporary ponds and permanent streams is mainly realized by different genes with a converging functionality.


Assuntos
Aclimatação/genética , Ecossistema , Salamandra/genética , Adaptação Fisiológica/genética , Animais , Europa (Continente) , Expressão Gênica , Larva , Análise de Sequência com Séries de Oligonucleotídeos , Lagoas , Rios , Especificidade da Espécie , Transcriptoma
2.
J Neural Transm (Vienna) ; 122(11): 1573-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26179478

RESUMO

Continuous intrathecal Baclofen application (ITB) through an intracorporeal pump system is widely used in adults and children with spasticity of spinal and supraspinal origin. Currently, about 1200 new ITB pump systems are implanted in Germany each year. ITB is based on an interdisciplinary approach with neurologists, rehabilitation specialists, paediatricians and neurosurgeons. We are presenting the proceedings of a consensus meeting organised by IAB-Interdisciplinary Working Group for Movement Disorders. The ITB pump system consists of the implantable pump with its drug reservoir, the refill port, an additional side port and a flexible catheter. Non-programmable pumps drive the Baclofen flow by the reservoir pressure. Programmable pumps additionally contain a radiofrequency control unit, an electrical pump and a battery. They have major advantages during the dose-finding phase. ITB doses vary widely between 10 and 2000 µg/day. For spinal spasticity, they are typically in the order of 100-300 µg/day. Hereditary spastic paraplegia seems to require particularly low doses, while dystonia and brain injury require particularly high ones. Best effects are documented for tonic paraspasticity of spinal origin and the least effects for phasic muscle hyperactivity disorders of supraspinal origin. Oral antispastics are mainly effective in mild spasticity. Botulinum toxin is most effective in focal spasticity. Myotomies and denervation operations are restricted to selected cases of focal spasticity. Due to its wide-spread distribution within the cerebrospinal fluid, ITB can tackle wide-spread and severe spasticity.


Assuntos
Baclofeno/administração & dosagem , Transtornos dos Movimentos/tratamento farmacológico , Relaxantes Musculares Centrais/administração & dosagem , Espasticidade Muscular/tratamento farmacológico , Alemanha , Humanos , Bombas de Infusão Implantáveis/efeitos adversos , Injeções Espinhais
3.
J Evol Biol ; 26(2): 229-46, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23323997

RESUMO

Hybridization has many and varied impacts on the process of speciation. Hybridization may slow or reverse differentiation by allowing gene flow and recombination. It may accelerate speciation via adaptive introgression or cause near-instantaneous speciation by allopolyploidization. It may have multiple effects at different stages and in different spatial contexts within a single speciation event. We offer a perspective on the context and evolutionary significance of hybridization during speciation, highlighting issues of current interest and debate. In secondary contact zones, it is uncertain if barriers to gene flow will be strengthened or broken down due to recombination and gene flow. Theory and empirical evidence suggest the latter is more likely, except within and around strongly selected genomic regions. Hybridization may contribute to speciation through the formation of new hybrid taxa, whereas introgression of a few loci may promote adaptive divergence and so facilitate speciation. Gene regulatory networks, epigenetic effects and the evolution of selfish genetic material in the genome suggest that the Dobzhansky-Muller model of hybrid incompatibilities requires a broader interpretation. Finally, although the incidence of reinforcement remains uncertain, this and other interactions in areas of sympatry may have knock-on effects on speciation both within and outside regions of hybridization.


Assuntos
Especiação Genética , Hibridização Genética , Adaptação Fisiológica , Animais , Fluxo Gênico , Fenótipo
4.
Heredity (Edinb) ; 111(6): 520-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23981957

RESUMO

Cottus rhenanus and Cottus perifretum have formed hybrid lineages and narrow hybrid zones that can be best explained through the action of natural selection. However, the underlying selective forces as well as their genomic targets are not well understood. This study identifies genomic regions in the parental species that cause hybrid incompatibilities and tests whether these manifest in a sex-specific manner to learn about processes that affect natural hybridization in Cottus. Interspecific F2 crosses were analyzed for 255 markers for genetic mapping and to detect transmission distortion as a sign for genetic incompatibilities. The Cottus map consists of 24 linkage groups with a total length of 1575.4 cM. A male heterogametic (XY) sex determination region was found on different linkage groups in the two parental species. Genetic incompatibilities were incomplete, varied among individuals and populations and were not associated with the heterogametic sex. The variance between populations and individuals makes it unlikely that there are species-specific incompatibility loci that could affect the gene pool of natural hybrids in a simple and predictable way. Conserved synteny with sequenced fish genomes permits to genetically study the Cottus genome through the transfer of genomic information from the model fish species. Homology relationships of candidate genomic regions in Cottus indicate that sex determination is not based on the same genomic regions found in other fish species. This suggests a fast evolutionary turnover of the genetic basis of sex determination that, together with the small size of the heterogametic regions, may contribute to the absence of fitness effects related to the Haldane's rule.


Assuntos
Hibridização Genética , Perciformes/genética , Processos de Determinação Sexual , Animais , Evolução Biológica , Mapeamento Cromossômico , Cruzamentos Genéticos , Feminino , Ligação Genética , Genômica , Masculino , Perciformes/fisiologia
5.
Ann Med ; 54(1): 1265-1276, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35510813

RESUMO

BACKGROUND: Lower socioeconomic status (SES) is associated with higher mortality rates and the likelihood of receiving less evidence-based treatment after stroke. In contrast, little is known about the impact of SES on recovery after discharge from inpatient rehabilitation. The aim of this study was to investigate the influence of SES on long-term recovery after stroke. PATIENTS AND METHODS: In a prospective, observational, multicentre study, inpatients were recruited towards the end of rehabilitation. The 12-month follow-up focussed on upper limb motor recovery, measured by the Fugl-Meyer score. A clinically relevant improvement of ≥5.25 points was considered recovery. Patient-centric measures such as the Patient-reported Outcomes Measurement Information System-Physical Health (PROMIS-10 PH) provided secondary outcomes. Information on schooling, vocational training, income and occupational status pre-stroke entered a multidimensional SES index. Multivariate logistic regression models calculating odds ratios (ORs) and corresponding confidence intervals (CIs) were applied. SES was added to an initial model including age, sex and baseline neurological deficit. Additional exploratory analyses examined the association between SES and outpatient treatment. RESULTS: One hundred and seventy-six patients were enrolled of whom 98 had SES and long-term recovery data. Model comparisons showed the SES-model superior to the initial model (Akaike information criterion (AIC): 123 vs. 120, Pseudo R2: 0.09 vs. 0.13). The likelihood of motor recovery (OR = 17.12, 95%CI = 1.31; 224.18) and PROMIS-10 PH improvement (OR = 20.76, 95%CI = 1.28; 337.11) were significantly increased with higher SES, along with more frequent use of outpatient therapy (p = .02). CONCLUSIONS: Higher pre-stroke SES is associated with better long-term recovery after discharge from rehabilitation. Understanding these factors can improve outpatient long-term stroke care and lead to better recovery.KEY MESSAGEHigher pre-stroke socioeconomic status (SES) is associated with better long-term recovery after discharge from rehabilitation both in terms of motor function and self-reported health status.Higher SES is associated with significantly higher utilization of outpatient therapies.Discharge management of rehabilitation clinics should identify and address socioeconomic factors in order to detect individual needs and to improve outpatient recovery. Article registration: clinicaltrials.gov NCT04119479.


Assuntos
Reabilitação Neurológica , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Pacientes Internados , Estudos Prospectivos , Recuperação de Função Fisiológica , Classe Social , Reabilitação do Acidente Vascular Cerebral/métodos , Resultado do Tratamento , Extremidade Superior
6.
Thorac Cardiovasc Surg ; 59(6): 322-8, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21692023

RESUMO

BACKGROUND: Acute rejection reactions and the development of graft arterial disease are serious limitations after transplantation. Both are connected to the expression of adhesion molecules on the activated microvascular endothelium of the allograft. METHODS: siRNA-mediated silencing of ESELE, ICAM-1, and VCAM-1 on human cardiac microvascular cells (HCMEC) was investigated in order to inhibit leukocyte-endothelial interactions. HCMEC were investigated for the time-dependent expression of ESELE, ICAM-1, and VCAM-1 after TNF-α stimulation and for siRNA mediated suppression using a nonviral transfecting approach. Furthermore, the effects of siRNA transfection on leukocyte binding to the endothelium were analyzed. RESULTS: Transfection with siRNA induced a significant suppression of adhesion molecule expression, regardless of whether there had been a prior single or cocktail transfection of the sequences ( P < 0.05). The quantity of attaching leukocytes was significantly reduced after an equal silencing of adhesion molecules ( P < 0.05). CONCLUSIONS: This investigation demonstrates that liposomal transfection of HCMEC with specific siRNA sequences is capable of both repressing adhesion molecule expression and of reducing subsequent leukocyte-endothelial actions.


Assuntos
Moléculas de Adesão Celular/genética , Vasos Coronários/metabolismo , Células Endoteliais/metabolismo , Microvasos/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Transfecção , Adesão Celular , Moléculas de Adesão Celular/metabolismo , Células Cultivadas , Técnicas de Cocultura , Vasos Coronários/citologia , Selectina E/genética , Citometria de Fluxo , Humanos , Molécula 1 de Adesão Intercelular/genética , Lipossomos , Microvasos/citologia , Neutrófilos/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Tempo , Fator de Necrose Tumoral alfa/metabolismo , Molécula 1 de Adesão de Célula Vascular/genética
7.
J Cardiovasc Surg (Torino) ; 52(2): 251-9, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21460776

RESUMO

AIM: Coronary artery bypass grafting (CABG) is a standard procedure for treatment of coronary heart disease. Eighty percent of all CABGs are performed with venous grafts which then get exposed to an arterial pressure after surgery. This widely used procedure, however, is complicated by the development of alterations in the vein graft wall, leading to a decreased patency rate and graft failure. This study enlightens the influence of an even moderate arterial pressure on the gene expression of adhesion molecules in venous grafts which play a decisive role for the early induction of atherogenesis. METHODS: Segments of porcine vena jugularis and arteria carotis were mounted in a simulated bypass circuit and subjected to pulsatile flow. Vessel segments were examined for adhesion molecule expression with quantitative real-time - polymerase chain reaction (qRT-PCR) and adherence of leukocytes was observed by confocal laser scanning microscopy and scanning electron microscopy. RESULTS: Veins grafts subjected to an even moderate arterial pressure showed a 14-fold increase of ICAM-1 expression already after 4 hours. An arterial pressure of around 100/80 mmHg was enough to stimulate the adhesion molecule expression Furthermore it led to a 9-fold increase of leukocyte adhesion to the venous endothelium, but, in contrast this was not the case in arteries. CONCLUSION: This study showed, that already 100 mmHg upregulates the expression of several adhesion molecules in pig veins followed by increased adhesion of leukocytes. Therefore, our data demonstrate the advantage of arteries for CABG, and that new therapeutic strategies are urgently necessary to protect vein grafts either physically or pharmacologically if arteries are not available for CABG.


Assuntos
Pressão Sanguínea , Artérias Carótidas/imunologia , Moléculas de Adesão Celular/metabolismo , Ponte de Artéria Coronária/efeitos adversos , Veias Jugulares/imunologia , Animais , Adesão Celular , Moléculas de Adesão Celular/genética , Selectina E/metabolismo , Feminino , Regulação da Expressão Gênica , Técnicas In Vitro , Molécula 1 de Adesão Intercelular/metabolismo , Veias Jugulares/transplante , Leucócitos/imunologia , Microscopia Confocal , Microscopia Eletrônica de Varredura , Perfusão , Fluxo Pulsátil , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Suínos , Fatores de Tempo , Molécula 1 de Adesão de Célula Vascular/metabolismo
8.
Mol Biol Evol ; 26(4): 925-36, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19174479

RESUMO

Genomewide analyses of the transcriptome have confirmed that gene misexpression may underlie reproductive isolation mechanisms in interspecific hybrids. Here, using a 16,006 features cDNA microarray, we compared and contrasted gene expression divergence at two ontogenetic stages in incipient species of normal and dwarf whitefish (Coregonus clupeaformis) with that of first generation (normal x dwarf) and second-generation hybrid crosses (backcross: [normal x dwarf] x normal]. Our goal was to identify the main mode of action responsible for gene transcription and to discover key genes misexpressed in hybrids. Very few transcripts (five of 4,950 expressed) differed in mean expression level between parentals and hybrids at the embryonic stage, in contrast to 16-week-old juvenile fish for which 617 out of 5,359 transcripts differed significantly. We also found evidence for more misexpression in backcross hybrids whereby nonadditivity explained a larger fraction of hybrid inheritance patterns in backcross (54%) compared with F1-hybrids (9%). Gene expression in hybrids was more variable than in pure crosses and transgressive patterns of expression were ubiquitous in hybrids. In backcross embryos in particular, the expression of three key developmental genes involved in protein folding and mRNA translation was severely disrupted. Accordingly, gene misexpression in hybrids adds to other factors previously identified as contributing to the reproductive isolation of incipient species of lake whitefish.


Assuntos
Perfilação da Expressão Gênica , Salmonidae/genética , Animais , Cruzamentos Genéticos , Feminino , Masculino , Análise de Sequência com Séries de Oligonucleotídeos
9.
Mol Ecol ; 18(12): 2615-27, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19457191

RESUMO

Theory predicts that reproductive isolation may be due to intrinsic genetic incompatibilities or extrinsic ecological factors. Therefore, an understanding of the genetic basis of isolation may require analyses of evolutionary processes in situ to include environmental factors. Here we study genetic isolation between populations of sculpins (Cottus) at 168 microsatellites. Genomic clines were fit using 480 individuals sampled across independent natural hybrid zones that have formed between one invading species and two separate populations of a resident species. Our analysis tests for deviations from neutral patterns of introgression at individual loci based on expectations given genome-wide admixture. Roughly 51% of the loci analysed displayed significant deviations. An overall deficit of interspecific heterozygotes in 26% and 21% of the loci suggests that widespread underdominance drives genomic isolation. At the same time, selection promotes introgression of almost 30% of the markers, which implies that hybridization may increase the fitness of admixed individuals. Cases of overdominance or epistatic interactions were relatively rare. Despite the similarity of the two hybrid zones in their overall genomic composition, patterns observed at individual loci show little correlation between zones and many fit different genotypic models of fitness. At this point, it remains difficult to determine whether these results are due to differences in external selection pressures or cryptic genetic differentiation of distinct parental populations. In the future, data from mapped genetic markers and on variation of ecological factors will provide additional insights into the contribution of these factors to variation in the evolutionary consequences of hybridization.


Assuntos
Peixes/genética , Genética Populacional , Hibridização Genética , Seleção Genética , Alelos , Animais , Evolução Molecular , Frequência do Gene , Marcadores Genéticos , Especiação Genética , Variação Genética , Repetições de Microssatélites , Modelos Genéticos , Reprodução/genética , Análise de Sequência de DNA
10.
Sci Rep ; 8(1): 4820, 2018 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-29556088

RESUMO

How organisms adapt to unfavorable environmental conditions by means of plasticity or selection of favorable genetic variants is a central issue in evolutionary biology. In the Maipo River basin, the fish Basilichthys microlepidotus inhabits polluted and non-polluted areas. Previous studies have suggested that directional selection drives genomic divergence between these areas in 4% of Amplified Fragment Length Polymorphism (AFLP) loci, but the underlying genes and functions remain unknown. We hypothesized that B. microlepidotus in this basin has plastic and/or genetic responses to these conditions. Using RNA-Seq, we identified differentially expressed genes in individuals from two polluted sites compared with fish inhabiting non-polluted sites. In one polluted site, the main upregulated genes were related to cellular proliferation as well as suppression and progression of tumors, while biological processes and molecular functions involved in apoptotic processes were overrepresented in the upregulated genes of the second polluted site. The ornithine decarboxylase gene (related to tumor promotion and progression), which was overexpressed in both polluted sites, was sequenced, and a parallel pattern of a heterozygote deficiency and increase of the same homozygote genotype in both polluted sites compared with fish inhabiting the non-polluted sites was detected. These results suggest the occurrence of both a plastic response in gene expression and an interplay between phenotypic change and genotypic selection in the face of anthropogenic pollution.


Assuntos
Proteínas de Peixes/genética , Peixes/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Marcadores Genéticos , Ornitina Descarboxilase/genética , Seleção Genética , Poluentes Químicos da Água/toxicidade , Animais , Evolução Biológica , Poluição Ambiental/efeitos adversos , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Polimorfismo Genético
11.
Nat Biotechnol ; 14(9): 1112-5, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9631061

RESUMO

A 58-mer L-RNA ligand that binds to naturally occurring D-adenosine with a dissociation constant of 1.7 microM in solution was identified from a combinatorial library employing mirror-design. The corresponding D-RNA ligand shows identical binding affinity to L-adenosine. Reciprocal chiral specificity was also evident from ligand discrimination; the binding affinity of the L-RNA ligand for D-adenosine was 9000-fold greater than its affinity for L-adenosine and vice versa. While the D-RNA ligand was rapidly degraded in human serum, the L-RNA ligand displayed an extraordinary stability. This indicates the potential application of specifically designed L-RNA ligands as stable monoclonal antibody analogues and the development of highly stable L-ribozymes.


Assuntos
Adenosina/metabolismo , RNA/química , RNA/metabolismo , Adenosina/química , Sequência de Bases , Sítios de Ligação , Ligação Competitiva , Biotecnologia , Sequência Consenso , Sequência Conservada , DNA/genética , Estabilidade de Medicamentos , Humanos , Técnicas In Vitro , Ligantes , Dados de Sequência Molecular , Conformação de Ácido Nucleico , RNA/genética , Homologia de Sequência do Ácido Nucleico , Estereoisomerismo
12.
Nat Biotechnol ; 14(9): 1116-9, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9631062

RESUMO

The high affinity and selectivity of nucleic acid ligands have clearly demonstrated that RNA can be targeted to a variety of molecules. In practice, however, the use of unmodified aptamers is impeded by the low stability of RNA in biological fluids. Here we describe the mirror-design of a stable 38-mer L-oligoribonucleotide ligand that binds to L-arginine. This L-RNA ligand was also able to bind to a short peptide containing the basic region of the human immunodeficiency virus type-1 Tat-protein. The L-RNA ligand displayed the expected stability in human serum. These findings may contribute to the identification of novel diagnostics and pharmaceuticals.


Assuntos
Arginina/metabolismo , Oligonucleotídeos/química , Oligonucleotídeos/metabolismo , Sequência de Aminoácidos , Arginina/análogos & derivados , Arginina/química , Sequência de Bases , Sítios de Ligação , Biotecnologia , Sequência Consenso , Estabilidade de Medicamentos , Produtos do Gene tat/genética , Produtos do Gene tat/metabolismo , HIV-1/genética , HIV-1/metabolismo , Humanos , Técnicas In Vitro , Cinética , Ligantes , Conformação de Ácido Nucleico , Oligonucleotídeos/genética , Ligação Proteica , RNA/química , RNA/genética , RNA/metabolismo , Homologia de Sequência do Ácido Nucleico , Estereoisomerismo , Produtos do Gene tat do Vírus da Imunodeficiência Humana
14.
Artigo em Alemão | MEDLINE | ID: mdl-26763526

RESUMO

A male, 12-year-old Cairn terrier suffering from Cushing's syndrome with two therapy-resistant inflammatory subcutaneous lesions was examined pathomorphologically and parasitologically. Within the subcutaneous tissue, there was a suppurative to necrotizing and histiocytic inflammation present with the formation of caverns. Intralesional whitish-grey cysts with a diameter of 1-4 mm were detected. Molecular investigations of the cysts confirmed the preliminary morphological identification as Cysticercus longicollis. The adenohypophysis showed an infiltrative growing carcinoma. Cysticercus longicollis is the metacestode of Taenia (T.) crassiceps, a tapeworm of foxes and coyotes. Small rodents are typical intermediate hosts, in which the metacestode develops within the body cavities as well as in the subcutis. Subcutaneous cysticercosis after infection with eggs of T. crassiceps is also described in different domestic animal species and in humans, who represent aberrant intermediate hosts. Immunosuppression due to Cushing's syndrome, probably caused by the tumor of the adenohypophysis, may have played a role in the pathogenesis of the present case.


Assuntos
Síndrome de Cushing/veterinária , Cisticercose/veterinária , Doenças do Cão/patologia , Doenças do Cão/parasitologia , Animais , Síndrome de Cushing/parasitologia , Cisticercose/complicações , Cisticercose/diagnóstico , Cães , Masculino
15.
Clin Cancer Res ; 7(1): 51-7, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11205918

RESUMO

The reduction of residual tumor cells is one of the main targets of leukapheresis product (LP) processing. Immunomagnetic enrichment/selection of CD34+ progenitor cells (Baxter Isolex 300i) can achieve a reduction of contaminating B-cells of approximately 2-3 logs in B-cell non-Hodgkin's lymphoma patients. Specific release of the enriched CD34+ cells (stem cell releasing agent PR34+; Baxter) and the use of antibody-coated immunobeads targeted against B-cell markers (CD10, CD19, CD20, CD22, CD23, and CD37) during this procedure allows the GMP-like simultaneous capture of residual B cells within a closed system. This combination of two purging techniques enhances the B-cell depletion capacity up to 4.5 logs. By performing 10 clinical-scale purging procedures, we could show that the simultaneous immunomagnetic purging method is easy to perform and highly efficient. We evaluated B-cell log depletion by flow cytometry for cases with marker-positive cells detectable before and after the purging procedure. The mean reduction of B-cells in these cases was 3.5 logs; the mean CD34+ cell yield and purity were 47 and 92%. Using three LPs, we tested the procedure on a modified Baxter Isolex 300i device with software adaptations for this procedure (software version 2.0) in direct comparison with CD34+ cell selection only, using the former version (version 1.12). The CD34+ cell yield was 49% (40-54%) for the CD34+ cell selection and 51% (19-72%) for simultaneous double selection. The mean purity was 96% for CD34+ cell selection and 98% for simultaneous double selection. B-cell depletion was 1.9 logs for CD34+ cell selection, and after simultaneous double selection, the B-cell content was decreased by 3.7 log steps (P = 0.0495). Clinical application of double-purged cells has not prolonged the hematopoietic recovery times after high-dose therapy as compared with nonpurged peripheral blood progenitor cell autotransplants. In conclusion, we could show that the simultaneous double selection protocol developed leads to a highly increased B-cell purging efficacy when compared with CD34+ cell selection without any negative effects regarding CD34+ cell yield and engraftment times after high-dose therapy.


Assuntos
Antígenos CD34/imunologia , Linfócitos B/imunologia , Depleção Linfocítica , Linfoma de Células B/imunologia , Células-Tronco/imunologia , Sobrevivência Celular/fisiologia , Intervalo Livre de Doença , Citometria de Fluxo , Humanos , Separação Imunomagnética/métodos , Leucaférese/métodos , Resultado do Tratamento
16.
Biol Psychiatry ; 45(6): 694-703, 1999 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-10187999

RESUMO

BACKGROUND: Eye tracking dysfunction (ETD) has been put forward as a trait marker for biological susceptibility to schizophrenia with the hope of identifying a link to specific cerebral lesions. METHODS: Eye movements were recorded using infrared oculography in 8 families (67 members) showing multiple occurrence of schizophrenia and in 9 nonpsychotic families (80 members). Triangle wave stimuli at 15 degrees/s and 30 degrees/s were used and gains (eye velocity/target velocity), rates and amplitudes of different saccade categories (catch-up, back-up, anticipatory saccades, and squarewave-jerks) were determined. RESULTS: In the relatives, the same deficit in maintenance of smooth pursuit performance was found as was seen in the schizophrenic patients. This deficit, which was not observed in the nonpsychotic families, consisted of lower gains for leftward as compared to rightward pursuit. This was emphasized most clearly at 30 degrees/s and was associated with an excess of catch-up saccades in the schizophrenic patients, whereas in the relatives a tendency to exhibit more and larger anticipatory saccades was observed. CONCLUSIONS: The results confirm the hypothesis that eye-tracking dysfunction is a phenotypic marker for genetic liability to schizophrenia. Neurophysiologically, a cerebral dysfunction which includes one or more of the oculomotor centers can be assumed in subjects who carry a genetic susceptibility to schizophrenia.


Assuntos
Encéfalo/fisiopatologia , Acompanhamento Ocular Uniforme/fisiologia , Movimentos Sacádicos/fisiologia , Esquizofrenia/genética , Esquizofrenia/fisiopatologia , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo
17.
FEBS Lett ; 429(2): 211-5, 1998 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-9650592

RESUMO

The synthetic RNA fragment 5'-CUGGGCGG(GCGA)CCGCCUGG (nucleotides in parentheses indicate the loop region) corresponds to the natural sequence of domain E from nucleotides 79-97 of the Thermus flavus 5S rRNA including a hairpin loop. The RNA structure determined at 3.0 A and refined to an R-value of 24.1% also represents the first X-ray structure GNRA tetraloop. The loop is in distinctly different conformation from other GNRA tetraloops analyzed by NMR. The conformation of the two molecules in the asymmetric unit is influenced and stabilized by specific intermolecular contacts. The structural features presented here give evidence for the ability of RNA molecules to adapt to specific environments.


Assuntos
Conformação de Ácido Nucleico , RNA Bacteriano/química , RNA Ribossômico 5S/química , Thermus/genética , Sequência de Bases , Cristalografia por Raios X , Modelos Moleculares , Dados de Sequência Molecular
18.
FEBS Lett ; 374(2): 292-4, 1995 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-7589556

RESUMO

The ribosomal 5S RNA is an essential constituent of the large ribosomal subunit. To overcome the difficulties of crystallizing large RNA molecules such as 5S rRNAs, we decided to divide the 5S rRNA in five domains A through E to determine their structure. Recently we determined the crystal structural of the helical domain A. Here we report the crystallization of the chemically synthesized domain E of the Thermus flavus 5S rRNA. The crystal form is trigonal with unit cell dimensions: a = b = 42.80 A and c = 162.20 A. Diffraction-data to 2.8 A have been recorded and the structure solution is currently underway by means of MIR and MAD techniques.


Assuntos
Conformação de Ácido Nucleico , RNA Ribossômico 5S/química , Thermus/genética , Sequência de Bases , Sítios de Ligação , Cristalografia por Raios X , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Estrutura Molecular , Oligorribonucleotídeos/análise , RNA Bacteriano/química , RNA Bacteriano/isolamento & purificação , RNA Ribossômico 5S/isolamento & purificação , Temperatura
19.
Am J Med Genet ; 67(6): 564-79, 1996 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-8950416

RESUMO

The difficulties in defining the borders of the schizophrenia spectrum is one major source of variance in linkage studies of schizophrenia. The employment of biological markers may prove advantageous. Due to empirical evidence, eye tracking dysfunction (ETD) has been discussed to be the most promising marker for genetic liability to schizophrenia. With respect to the recent progress in genomic scans, which have pointed to the short arm of chromosome 6, we carried out a scan of the 6p21-23 region with 16 microsatellite markers to test for linkage between chromosomal markers and ETD as well as schizophrenia. We tested 5 models of inheritance of ETD and found maximum two-point lod scores of 3.51 for D6S271 and 3.44 for D6S282. By including these markers in a multipoint analysis, a lod score of 4.02 was obtained. In the case of schizophrenia, 7 models were tested; however, with non-significant results. Our findings, together with another recent linkage report, point to the possibility of a second susceptibility locus for schizophrenia which may be located centromeric to the HLA region. Also, the evidence of ETD being a susceptibility marker for schizophrenia receives further support.


Assuntos
Cromossomos Humanos Par 6 , Transtornos da Motilidade Ocular/complicações , Esquizofrenia/genética , Adulto , Idoso , Biomarcadores , Ligação Genética , Humanos , Raios Infravermelhos , Pessoa de Meia-Idade , Linhagem , Esquizofrenia/complicações , Esquizofrenia/diagnóstico
20.
Bone Marrow Transplant ; 21(9): 909-16, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9613783

RESUMO

The cytolytic T lymphocyte (CTL) response has often been used to assess the reconstitution of T cell function after allogeneic or autologous bone marrow transplantation (BMT). Less is known, however, about the reconstitution of the CTL response after peripheral blood stem cell transplantation (PBSCT). Therefore, we investigated the CTL response against Epstein-Barr virus (EBV) of patients undergoing autologous PBSCT. CTLs of six patients with relapsed non-Hodgkin's lymphoma and multiple myeloma were established before and at different times after PBSCT by in vitro stimulation of peripheral blood lymphocytes with autologous EBV-transformed lymphoblastoid cell lines (LCLs). The efficiency of T cell priming by LCLs was assessed at the time of initiation of CTL lines; the proliferative response was strongly reduced during the first 4 months and increased 5 months or more following PBSCT. Cytolytic activity was measured after three or four restimulations of CTLs. All patients investigated had a detectable EBV-specific CTL response which was poor during the first weeks after transplantation, accompanied by a strong non-MHC-restricted cytotoxic activity and a high proportion of CD56-positive T cells. Five or more months after PBSCT, a specific CTL response against EBV was seen which was similar to the situation prior to PBSCT, while the unspecific cytotoxic response decreased. Blocking experiments with monoclonal anti-CD3, anti-CD8 or anti-MHC I antibodies resulted in substantial inhibition of autologous LCL lysis, whereas anti-CD4 or anti-MHC II antibodies had no effect. Finally, autologous PHA blasts of a patient with the HLA haplotype A1/9+, B5/8+, Cw4/7+, were loaded with various EBNA-derived nonapeptides known to be presented by HLA B8 or A11, and exposed to autologous, EBV-directed CTLs. Specific lysis by CTLs only occurred with HLA B8-, but not with HLA A11-restricted nonapeptides. This demonstrated the existence of an MHC I-restricted anti-EBV CTL response after PBSCT. Taken together, the results show that the anlaysis of the EBV-directed CTL activity may serve as a surrogate marker to assess the reconstitution of the cellular immune response in patients undergoing autologous PBSCT.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Herpesvirus Humano 4/imunologia , Linfoma não Hodgkin/imunologia , Linfoma não Hodgkin/terapia , Linfócitos T Citotóxicos/imunologia , Sequência de Aminoácidos , Anticorpos Monoclonais/farmacologia , Concanavalina A/farmacologia , Epitopos/química , Feminino , Antígenos HLA , Humanos , Imunidade Celular , Técnicas In Vitro , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Oligopeptídeos/química , Oligopeptídeos/imunologia , Fatores de Tempo , Transplante Autólogo
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