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1.
Alcohol ; 114: 61-68, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37661002

RESUMEN

BACKGROUND: Autonomic symptoms in alcohol withdrawal syndrome (AWS) are associated with a sympathetic-driven imbalance of the autonomic nervous system. To restore autonomic balance in AWS, novel neuromodulatory approaches could be beneficial. We conducted a pilot trial with percutaneous auricular vagus nerve stimulation (pVNS) in AWS and hypothesized that pVNS will enhance the parasympathetic tone represented by a reduction of pupillary dilation in a parasympatholytic pharmacological challenge. METHODS: Thirty patients suffering from alcohol use disorder, undergoing AWS, and stable on medication, were recruited in this open-label, single-arm pilot trial with repeated-measure design. Peripheral VNS (monophasic volt impulses of 1 msec, alternating polarity, frequency 1 Hz, amplitude 4 mV) was administered at the left cymba conchae for 72 h, followed by pupillometry under a tropicamide challenge. We assessed craving with a visual analog scale. We used pupillary mean as the dependent variable in a repeated-measures ANOVA (rmANOVA). RESULTS: A repeated-measures ANOVA resulted in a significant difference for pupillary diameter across time and condition (F(2,116) = 27.97, p < .001, ηp2 > .14). Tukey-adjusted post hoc analysis revealed a significant reduction of pupillary diameter after pVNS. Alcohol craving was significantly reduced after pVNS (p < .05, Cohen's d = 1.27). CONCLUSION: Our study suggests that pVNS activates the parasympathetic nervous system in patients with acute AWS, and that this activation is measurable by pupillometry. To this end, pVNS could be beneficial as a supportive therapy for AWS. Potential confounding effects of anti-craving treatment should be kept in mind.


Asunto(s)
Alcoholismo , Síndrome de Abstinencia a Sustancias , Estimulación del Nervio Vago , Humanos , Alcoholismo/terapia , Sistema Nervioso Autónomo , Proyectos Piloto , Síndrome de Abstinencia a Sustancias/tratamiento farmacológico
2.
Ophthalmologe ; 116(12): 1207-1211, 2019 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-30980176

RESUMEN

This article presents the case of a young male patient with complete congenital stationary night blindness (CSNB1). The informative value of the general medical history and clinical findings for the diagnosis was impaired due to language barriers and low compliance. Full-field electroretinography and optical coherence tomography help to define particular hereditary retinal dystrophies. Molecular genetic analysis by next generation sequencing as a part of multimodal diagnostics finally uncovered a rare, causal missense mutation in the nyctalopin (NYX) gene.


Asunto(s)
Enfermedades Hereditarias del Ojo , Enfermedades Genéticas Ligadas al Cromosoma X , Miopía , Ceguera Nocturna , Proteoglicanos , Electrorretinografía , Enfermedades Hereditarias del Ojo/diagnóstico por imagen , Enfermedades Hereditarias del Ojo/genética , Enfermedades Genéticas Ligadas al Cromosoma X/diagnóstico por imagen , Enfermedades Genéticas Ligadas al Cromosoma X/genética , Humanos , Masculino , Mutación , Miopía/diagnóstico por imagen , Miopía/genética , Ceguera Nocturna/diagnóstico por imagen , Ceguera Nocturna/genética , Proteoglicanos/genética
3.
Klin Monbl Augenheilkd ; 232(3): 250-8, 2015 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-25803554

RESUMEN

An early diagnosis of inherited retinal or optic nerve disorders is often delayed due to unspecific clinical signs, multiple clinical manifestations and striking genetic heterogeneity of the underlying molecular defects. This study represents a retrospective analysis of findings in 4,021 patients with inherited retinal or optic nerve disorders seen between 1986 and 2014 (1,171 with follow-up). In addition to the basic ophthalmological examination, electrophysiological tests (ERG, n = 2,088, since 1986; EOG, n = 381, since 1986; VEP n = 595, since 1986; mfERG, n = 819, since 1998) and non-invasive retinal imaging (fundus autofluorescence (FAF, n = 1,784, since 2002), near-infrared autofluorescence (NIA, n = 1,091, since 2006), spectral domain OCT (SD-OCT, n = 848, since 2008) and three-wavelengths multicolour spectral reflection imaging (MC, n = 366, since 2013) were performed at least once. Molecular DNA testing was done in 383 patients between 2006 and 2014. Based on these data an efficient diagnostic strategy is suggested: 1) inclusion of inherited retinal and optic nerve disorders into the differential diagnosis of visual loss or visual field defects with undefined causes; 2) non-invasive retinal imaging; 3) electrophysiological tests; 4) DNA testing to confirm the initial clinical diagnosis; 5) examination in specialised centres, therapy and follow-up. In recent years, the spectrum of diagnostic techniques has continuously expanded. Importantly, non-invasive retinal imaging has become the primary diagnostic tool and DNA testing based on state-of-the-art high throughput techniques increases the identification of associated gene mutations. In conclusion, a structured process in the diagnostic procedure of inherited retinal and optic nerve disorders greatly reduces a diagnostic delay, enables an earlier counselling and therapy and avoids further unnecessary diagnostic tests.


Asunto(s)
Técnicas de Diagnóstico Oftalmológico , Pruebas Genéticas/métodos , Enfermedades del Nervio Óptico/diagnóstico , Enfermedades del Nervio Óptico/genética , Enfermedades de la Retina/diagnóstico , Enfermedades de la Retina/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Niño , Preescolar , Femenino , Predisposición Genética a la Enfermedad/genética , Alemania , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Patología Molecular/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto Joven
4.
Ophthalmologe ; 102(2): 116-21, 2005 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-15627199

RESUMEN

Best's vitelliform macular dystrophy (Best's disease) is an autosomal dominant disease of the central retina and is caused by mutations in the VMD2 gene located on the long arm of chromosome 11. VMD2 encodes bestrophin, a transmembrane protein with putative Ca(2+)-dependent chloride channel activity at the basolateral portion of the retinal pigment epithelium. The N-terminal half of bestrophin reveals high sequence homology to three bestrophin-like proteins in humans but also to protein sequences from evolutionarily distant organisms. Most of the known VMD2 mutations are located within this presumably important functional part of the protein and cause amino acid substitutions and small in-frame deletions of single amino acid residues. The pathogenicity of VMD2 mutations is likely based on a dominant negative effect possibly by oligomerization of normal and mutated bestrophin molecules to form a defective ion channel. Missense mutations in VMD2 were also shown to be associated with vitreoretinochoroidopathy and ocular developmental abnormalities. In this case, the pathogenic sequence changes influence the peptide sequences but simultaneously alter the regulation of mRNA splicing and maturation. Different disease mechanisms may therefore be responsible for the distinct phenotypes associated with VMD2 mutations.


Asunto(s)
Cromosomas Humanos Par 11 , Distrofias Hereditarias de la Córnea/genética , Proteínas del Ojo/genética , Proteínas del Ojo/metabolismo , Predisposición Genética a la Enfermedad/genética , Degeneración Macular/metabolismo , Bestrofinas , Biomarcadores/metabolismo , Canales de Cloruro/metabolismo , Distrofias Hereditarias de la Córnea/diagnóstico , Distrofias Hereditarias de la Córnea/metabolismo , Proteínas del Ojo/química , Humanos , Degeneración Macular/diagnóstico , Degeneración Macular/genética , Polimorfismo Genético , Enfermedades de la Retina/diagnóstico , Enfermedades de la Retina/genética , Enfermedades de la Retina/metabolismo , Factores de Riesgo , Relación Estructura-Actividad
5.
Cytogenet Genome Res ; 105(1): 107-14, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15218265

RESUMEN

Mutations in the human vitelliform macular dystrophy type 2 (VMD2) gene are known to cause autosomal dominant Best macular dystrophy (BMD), a degenerative disorder of the central retina. VMD2, together with VMD2L1, VMD2L2 and VMD2L3, belong to a closely related gene family characterized by several transmembrane (TM) spanning helical domains and an invariant arginine, phenylalanine and proline (RFP) tripeptide motif, thus termed VMD2 RFP-TM. The four genes are thought to encode a novel family of anion channels. We now report the cloning and characterization of the murine orthologs by combining biocomputational analyses and molecular genetic approaches. While the murine Vmd2, Vmd2l1 and Vmd2l3 genes are functional, murine Vmd2l2p was found to be a non-transcribed pseudogene. Expression profiling of the murine Vmd2 RFP-TM family members revealed tissue-restricted expression with predominant transcription of Vmd2 in testis, of Vmd2l1 in colon and of Vmd2l3 in heart. Differential splicing was observed for Vmd2l3 in a number of tissues (e.g. in brain, retina/RPE, kidney) although the functional importance of the splice variants remains to be determined.


Asunto(s)
Proteínas del Ojo/genética , Empalme Alternativo , Animales , Secuencia de Bases , Bestrofinas , Canales de Cloruro , Clonación de Organismos , ADN Complementario , Proteínas de Unión al ADN/genética , Bases de Datos Genéticas , Etiquetas de Secuencia Expresada , Perfilación de la Expresión Génica , Humanos , Canales Iónicos , Ratones , Datos de Secuencia Molecular , Familia de Multigenes , Proteínas Nucleares/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Homología de Secuencia de Ácido Nucleico , Ubiquitina-Proteína Ligasas
6.
Blood Coagul Fibrinolysis ; 12(5): 375-83, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11505081

RESUMEN

Plasma samples of 189 healthy subjects were investigated for antigen levels of the recently reported factor VII- and single-chain plasminogen activator-activating protease (FSAP) and the corresponding pro-urokinase activating potencies. While the age of donors had no significant effect on the investigated parameters, female plasmas revealed a trend to higher antigen contents and activity levels. Surprisingly, as much as 9% of all samples contained significantly reduced single-chain urinary plasminogen activator activating potential, whereas antigen concentrations were normal. Additionally, 1% of the plasmas was found to decrease in both FSAP antigen and activity contents. FSAP of three subjects displaying reduced activities throughout a follow-up period of 6 months were purified from plasmas and were characterized. As compared with pool plasma derived FSAP, investigation of the individual preparations confirmed their reduced potency to activate pro-urokinase. However, factor VII activation was not affected. It is speculated that the FSAP binding site for single-chain plasminogen activators is affected, potentially by as yet unknown polymorphism(s) or mutation(s).


Asunto(s)
Serina Endopeptidasas/sangre , Serina Endopeptidasas/farmacología , Activador de Plasminógeno de Tipo Uroquinasa/metabolismo , Adulto , Factores de Edad , Anciano , Western Blotting , Electroforesis en Gel de Poliacrilamida , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proteínas Recombinantes/efectos de los fármacos , Proteínas Recombinantes/metabolismo , Serina Endopeptidasas/química , Factores Sexuales , Factores de Tiempo , Activador de Plasminógeno de Tipo Uroquinasa/química , Activador de Plasminógeno de Tipo Uroquinasa/efectos de los fármacos
7.
Psychiatr Prax ; 28(5): 246-8, 2001 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-11479833

RESUMEN

Primary progressive aphasia (PPA) is an uncommon neurodegenerative syndrome characterized by a relatively isolated dissolution of language function at the beginning, followed by deterioration of general cognitive function and of activities of daily living after 2 or more years. On account of neuropathological and clinical findings, PPA is supposed to form part of the spectrum of frontotemporal lobar degeneration. We present a case study of a 66-year-old woman with a probable fluent progressive aphasia. She initially experienced word amnesia and developed after 2 - 3 years gradual regression of word comprehension, over-fluent speech with semantic paraphasias, and at last generalized dementia. In addition to minor bilateral cortical volume reduction on CCT, MRI showed left temporal lobe atrophy involving hippocampus, SPECT revealed reduced uptake left frontal and temporal.


Asunto(s)
Afasia Progresiva Primaria/diagnóstico , Encéfalo/patología , Demencia/psicología , Indanos/uso terapéutico , Nootrópicos/uso terapéutico , Piperidinas/uso terapéutico , Anciano , Afasia Progresiva Primaria/tratamiento farmacológico , Afasia Progresiva Primaria/patología , Afasia Progresiva Primaria/fisiopatología , Atrofia , Encéfalo/diagnóstico por imagen , Demencia/etiología , Demencia/patología , Diagnóstico Diferencial , Donepezilo , Femenino , Humanos , Cintigrafía , Lóbulo Temporal/patología , Resultado del Tratamiento
8.
Artif Organs ; 25(6): 467-74, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11453877

RESUMEN

A newly developed implantable stimulator with 20 output channels, mainly intended for the stimulation of lower extremities in paraplegics, was implanted in 6 sheep over a time period of 26 weeks. Five epineural electrodes each were used to contact various nerves at different locations to elicit hip and knee extension and flexion and to make carrousel and selective stimulation possible. Different electrode application strategies in view of paraplegic standing and walking were investigated. Additional implanted electrodes allowed M-wave monitoring for selectivity investigations in 3 sheep. Stimulator, electrode leads, and electrodes proved to be reliable. Selective stimulation with electrodes placed on the trunk of the sciatic nerve could be demonstrated but with bad reproducibility. Histological investigation of the tissues surrounding electrodes and leads showed the expected stable foreign body response. Strong hip and knee extension could be gained in all cases while only weak flexion forces could be elicited in most cases. Muscle biopsies showed that daily stimulation for 8 h at threshold level caused an increase in muscle Type I fibers and a decrease in Type IIc fibers. Implants and electrodes fulfill the most important functional and biological criteria for their clinical application for paraplegic walking. The intention to provide selective flexion functions via epineural stimulation could not be demonstrated sufficiently in this animal model.


Asunto(s)
Terapia por Estimulación Eléctrica/instrumentación , Pierna/fisiología , Músculo Esquelético/fisiología , Traumatismos de la Médula Espinal/fisiopatología , Traumatismos de la Médula Espinal/terapia , Animales , Electrodos , Ovinos
9.
Eur J Biochem ; 268(13): 3789-96, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11432747

RESUMEN

Structural and biological characteristics of a recently described plasma serine protease, which displayed factor VII as well as pro-urokinase-activating properties in vitro, indicated a dual role for this factor VII-activating protease (FSAP) in hemostasis. Only the active protease (two-chain FSAP) has been isolated from plasma and from a prothrombin complex concentrate, whereas activators of the proenzyme have not been identified so far. After purification of the FSAP proenzyme from cryo-poor plasma by adsorption to an immobilized mAb and subsequent ion-exchange chromatography, activation to generate two-chain FSAP was followed by a direct chromogenic assay as well as by the ability of two-chain FSAP to activate pro-urokinase. Purified single-chain FSAP underwent autoactivation leading to the typical protease two-chain pattern and subsequent degradation products, as demonstrated by Western-blotting analysis using a site-specific mAb. This autoactivation was significantly enhanced in the presence of heparin, whereas Ca2+ ions stabilized single-chain FSAP (the proenzyme) resulting in slower autoactivation kinetics. Correspondingly, the heparin-augmented reaction, which was associated with autodegradation particularly of the protease domain, was slowed down by co-incubation with Ca2+. Of the other proteases and cofactors tested, only urokinase (uPA) was able to generate the typical two-chain FSAP pattern. Studies with different forms of uPA suggest that the catalytic activity of pro-urokinase/uPA is needed to activate single-chain FSAP, indicating that it is the only hemostatic protease that can act as a physiological activator of FSAP.


Asunto(s)
Precursores Enzimáticos/metabolismo , Factor VII/metabolismo , Serina Endopeptidasas/metabolismo , Coagulación Sanguínea , Cromatografía de Afinidad , Cromatografía por Intercambio Iónico , Electroforesis en Gel de Poliacrilamida , Activación Enzimática , Precursores Enzimáticos/química , Precursores Enzimáticos/aislamiento & purificación , Ensayo de Inmunoadsorción Enzimática , Fibrinólisis , Glicosilación , Humanos , Cinética , Peso Molecular , Monosacáridos/análisis , Procesamiento Proteico-Postraduccional , Serina Endopeptidasas/química , Serina Endopeptidasas/aislamiento & purificación
10.
Br J Ophthalmol ; 85(8): 969-75, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11466257

RESUMEN

BACKGROUND: A long term project was initiated to identify and to characterise genes that are expressed exclusively or preferentially in the retina as candidates for a genetic susceptibility to age related macular degeneration (AMD). A transcript represented by a cluster of five human expressed sequence tags (ESTs) derived exclusively from retinal cDNA libraries was identified. METHODS: Northern blot and RT-PCR analyses confirmed preferential retinal expression of the gene, which encodes a G protein coupled receptor, GPR75. Following isolation of the full length cDNA and determination of the genomic organisation, the coding sequence of GPR75 was screened for mutations in 535 AMD patients and 252 controls from Germany, the United States, and Italy. Employed methods included single stranded conformational polymorphism (SSCP) analysis, denaturing high performance liquid chromatography (DHPLC), and direct sequencing. RESULTS: Nine different sequence variations were identified in patients and control individuals. Three of these (-30A>C, 150G>A, and 346G>A) likely represent polymorphic variants. Each of six alterations (-4G>A, N78K, P99L, S108T, T135P, and Q234X) were found once in single AMD patients and were considered variants that could affect the protein function and potentially cause retinal pathology. CONCLUSION: The presence of six potential pathogenic variants in a cohort of 535 AMD patients alone does not provide statistically significant evidence for the association of sequence variation in GPR75 with genetic predisposition to AMD. However, a possible connection between the variants and age related retinal pathology cannot be discarded. Functional studies are needed to clarify the role of GPR75 in retinal physiology.


Asunto(s)
Etiquetas de Secuencia Expresada , Degeneración Macular/genética , Receptores de Superficie Celular/genética , Retina/metabolismo , Adulto , Distribución Binomial , Northern Blotting , Estudios de Casos y Controles , Cromatografía Líquida de Alta Presión , Biblioteca de Genes , Predisposición Genética a la Enfermedad , Humanos , Degeneración Macular/metabolismo , Masculino , Persona de Mediana Edad , Mutación/genética , Polimorfismo Conformacional Retorcido-Simple , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
11.
Genomics ; 74(3): 377-84, 2001 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-11414766

RESUMEN

To identify novel retina-specific genes systematically, we are performing expression profiling of retina ESTs that have been assembled in the human UniGene clusters. In this study, we report the 2619-bp full-length cDNA cloning and genomic organization of a gene corresponding to an EST cluster that was demonstrated to be exclusively present in retinal tissue. Alignment of the deduced amino acid sequence to sequence from protein databases revealed this gene, termed MPP4, to be a member of the membrane-associated guanylate kinase (MAGUK) protein family. It consists of 637 amino acids and contains the characteristic MAGUK motifs: an N-terminal PDZ domain, a central src homology 3 region (SH3), and a C-terminal guanylate kinase-like (GUK) domain. Due to the presence of only one PDZ motif, MPP4 is part of the p55 subfamily, named after the major palmitoylated erythrocyte membrane protein p55/MPP1. MAGUK proteins serve as molecular scaffolds to coordinate the membrane-associated cytoskeleton, ion channel and receptor clustering, signaling pathways, and the formation of cellular junctions. The abundant expression of MPP4 in the human retina suggests an important but so far unknown function in this tissue. Colocalization of MPP4 and autosomal recessive retinitis pigmentosa 26 (RP26) on chromosome 2q31-q33 makes this transcript an attractive candidate for the disease gene.


Asunto(s)
Proteínas Sanguíneas/genética , Proteínas de la Membrana/genética , Nucleósido-Fosfato Quinasa/genética , Retina/metabolismo , Empalme Alternativo , Northern Blotting , Mapeo Cromosómico , Cromosomas Humanos Par 2/genética , Clonación Molecular , ADN Complementario/química , ADN Complementario/genética , Exones , Femenino , Expresión Génica , Genes/genética , Guanilato-Quinasas , Humanos , Intrones , Masculino , Datos de Secuencia Molecular , Filogenia , ARN/genética , ARN/metabolismo , Análisis de Secuencia de ADN
12.
Br J Plast Surg ; 53(8): 669-75, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11090323

RESUMEN

In the present study we used the scutuloauricularis muscle in the rabbit to investigate the functional and morphometric alterations in the mimic-muscle system after cross-reinnervation. The scutuloauricularis muscle is the first experimental model that allows functional assessment of a mimic muscle by force measurements. A total of 36 rabbits were separated into three groups. In group 1 the scutuloauricularis nerve was cut and re-sutured to itself to achieve self-reinnervation; in group 2 the buccal nerve was used to cross-reinnervate the fast scutuloauricularis muscle and in group 3 the slow buccinator muscle was cross-reinnervated by the scutuloauricularis nerve. After a period of 6 months the maximal tetanic tensions of the reinnervated scutuloauricularis muscles were determined and histomorphometric examinations of muscle and nerve biopsies were carried out. Force measurements showed no loss of muscle force after self- and cross-reinnervation. The normal scutuloauricularis muscle contained 33%, and the buccinator muscle 46%, slow type I fibres. After self-reinnervation of the scutuloauricularis muscle the fibre-type composition remained unchanged. After cross-reinnervation we saw a significant fast-to-slow transformation of the scutuloauricularis muscle and a significant slow-to-fast transformation of the buccinator muscle. The number of myelinated nerve fibres in the scutuloauricularis nerve increased after cross-reinnervation from 1531 to 4077 (group 2) and to 3813 (group 3). The number of nerve fibres in the buccal nerve (3209) was unchanged after cross-reinnervation. The results of the present study might be relevant in the treatment of irreversible facial palsy by functional muscle transplantation and cross-face nerve grafting. The facial nerve branch used for cross-reinnervation seems to determine the functional outcome.


Asunto(s)
Músculos Faciales/inervación , Nervio Facial/cirugía , Transferencia de Nervios , Animales , Biopsia , Músculos Faciales/fisiología , Nervio Facial/patología , Nervio Facial/fisiología , Parálisis Facial/cirugía , Femenino , Contracción Muscular/fisiología , Fibras Nerviosas Mielínicas/fisiología , Conejos
13.
Am J Hum Genet ; 67(4): 800-13, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10958763

RESUMEN

Stargardt disease (STGD) is a common autosomal recessive maculopathy of early and young-adult onset and is caused by alterations in the gene encoding the photoreceptor-specific ATP-binding cassette (ABC) transporter (ABCA4). We have studied 144 patients with STGD and 220 unaffected individuals ascertained from the German population, to complete a comprehensive, population-specific survey of the sequence variation in the ABCA4 gene. In addition, we have assessed the proposed role for ABCA4 in age-related macular degeneration (AMD), a common cause of late-onset blindness, by studying 200 affected individuals with late-stage disease. Using a screening strategy based primarily on denaturing gradient gel electrophoresis, we have identified in the three study groups a total of 127 unique alterations, of which 90 have not been previously reported, and have classified 72 as probable pathogenic mutations. Of the 288 STGD chromosomes studied, mutations were identified in 166, resulting in a detection rate of approximately 58%. Eight different alleles account for 61% of the identified disease alleles, and at least one of these, the L541P-A1038V complex allele, appears to be a founder mutation in the German population. When the group with AMD and the control group were analyzed with the same methodology, 18 patients with AMD and 12 controls were found to harbor possible disease-associated alterations. This represents no significant difference between the two groups; however, for detection of modest effects of rare alleles in complex diseases, the analysis of larger cohorts of patients may be required.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/genética , Envejecimiento/fisiología , Pruebas Genéticas , Variación Genética/genética , Degeneración Macular/genética , Mutación/genética , Adolescente , Adulto , Edad de Inicio , Anciano , Anciano de 80 o más Años , Alelos , Niño , Preescolar , Cromatografía Líquida de Alta Presión , Cromosomas Humanos/genética , Estudios de Cohortes , Análisis Mutacional de ADN , Recolección de Datos , Exones/genética , Femenino , Efecto Fundador , Genes Recesivos/genética , Alemania/epidemiología , Homocigoto , Humanos , Intrones/genética , Degeneración Macular/diagnóstico , Degeneración Macular/epidemiología , Degeneración Macular/fisiopatología , Persona de Mediana Edad , Polimorfismo Conformacional Retorcido-Simple , Sitios de Empalme de ARN/genética
14.
Cytogenet Cell Genet ; 88(3-4): 211-6, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10828591

RESUMEN

We have cloned and characterized a novel gene (C11orf9) mapping to chromosome 11q12-->q13.1. The transcript was initially identified as a partial cDNA sequence in the course of constructing a transcript map of the region between markers D11S1765 and uteroglobin known to encompass the gene causing Best disease. Using a combination of EST mapping, computational exon prediction, RT-PCR, and 5'-RACE its 5. 7-kb full-length cDNA sequence was subsequently obtained. The C11orf9 gene consists of 26 exons spanning 33.1 kb of genomic DNA and is located about 4.3 kb centromeric to FEN1. Biocomputational analysis predicts that its conceptual translation product of 1,111 amino acids contains two transmembrane helices as well as two proline-rich regions. Alignment reveals significant homology to hypothetical peptides from several other species including C. elegans and D. melanogaster, indicating a high degree of conservation throughout evolution. Northern Blot and RT-PCR analyses demonstrate widespread expression of a single transcript but varying degrees of abundance among the individual tissues tested. Mutation analysis of the entire coding sequence excluded C11orf9 as the Best disease gene.


Asunto(s)
Cromosomas Humanos Par 11/genética , Secuencia Conservada/genética , Exones/genética , Intrones/genética , Proteínas de la Membrana/genética , Sistemas de Lectura Abierta/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , Análisis Mutacional de ADN , ADN Complementario/genética , Bases de Datos Factuales , Etiquetas de Secuencia Expresada , Perfilación de la Expresión Génica , Genes Dominantes/genética , Ligamiento Genético/genética , Humanos , Degeneración Macular/genética , Proteínas de la Membrana/química , Datos de Secuencia Molecular , Mapeo Físico de Cromosoma , ARN Mensajero/análisis , ARN Mensajero/genética , Alineación de Secuencia , Factores de Transcripción
15.
Genomics ; 66(2): 175-83, 2000 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-10860662

RESUMEN

The insertion of double bonds into specific positions of fatty acids is achieved by the action of distinct desaturase enzymes. Here we report the cloning and characterization of three members of the fatty acid desaturase (FADS) gene family in humans. Initially identified as cDNA fragments by direct cDNA selection within a defined 1.4-Mb region in 11q12-q13.1, full-length fatty acid desaturase-1 (FADS1) and fatty acid desaturase-2 (FADS2) transcripts were obtained by EST sequence assembly. A third member, fatty acid desaturase-3 (FADS3), was identified in silico revealing 62 and 70% nucleotide sequence identity with FADS1 and FADS2, respectively. The three genes are clustered within 92 kb of genomic DNA located 2 kb telomeric to FEN1 and 50 kb centromeric to VMD2 and are likely to have arisen evolutionarily from gene duplication as they share a remarkably similar exon/intron organization. Protein database searches identified FADS1, FADS2, and FADS3 as fusion products composed of an N-terminal cytochrome b5-like domain and a C-terminal multiple membrane-spanning desaturase portion.


Asunto(s)
Cromosomas Humanos Par 11 , Ácido Graso Desaturasas/genética , Secuencia de Aminoácidos , Secuencia de Bases , Mapeo Cromosómico , Clonación Molecular , ADN , ADN Complementario , delta-5 Desaturasa de Ácido Graso , Exones , Ácido Graso Desaturasas/química , Humanos , Intrones , Datos de Secuencia Molecular , Filogenia , Homología de Secuencia de Aminoácido
16.
Wien Klin Wochenschr ; 112(2): 75-9, 2000 Jan 28.
Artículo en Alemán | MEDLINE | ID: mdl-10703155

RESUMEN

The aim of the present investigation was to determine whether Fourier analysis of pupillary oscillations permits detection of differences in the activation of the central nervous system of opioid-addicted patients. We analysed pupillary oscillations during the recording period of static pupillometry, which lasted 25.6 s. Using Fourier analysis, the spectrum was divided into five frequency bands (0.0-0.20, 0.21-0.40, 0.41-0.60, 0.61-0.80, 0.81-1.0 Hz); the total spectrum (0-1 Hz) was also assessed. Three groups of patients were selected: the group addicted to heroin (consuming exclusively heroin) consisted of 26 patients with a mean age of 25.0 +/- 6.3 years, the methadone substitution group of 20 patients with a mean age of 30.9 +/- 8.2 years, and the morphine substitution group of 20 patients with a mean age of 33.2 +/- 4.6 years. The 3 patient groups were compared with normal controls of similar age (25.1 +/- 4.6 years). In the frequency band of 0.0-0.20 Hz the morphine group showed significantly lower amplitudes than the heroin group. Also in the frequency band of 0.41-0.60 Hz the morphine group differed significantly from the other groups concerning lower amplitudes, reflecting deactivation. In the total spectrum of 0 to 1 Hz the differences between these two groups were significant. Comparison with normal controls also showed significant differences. The groups were further divided according to dose (high/low): Patients of the heroin group as well as those of the methadone and morphine groups who had consumed higher doses showed greater activation of the central nervous system. In conclusion the morphine group was more deactivated than the methadone and heroin group and patients who received higher doses of the substances showed greater central nervous activation. Thus, the measurement of central nervous activation by means of Fourier analysis of pupillary oscillations might be useful in monitoring substitution therapy.


Asunto(s)
Encéfalo/efectos de los fármacos , Dependencia de Heroína/fisiopatología , Metadona/uso terapéutico , Dependencia de Morfina/fisiopatología , Reflejo Pupilar/efectos de los fármacos , Procesamiento de Señales Asistido por Computador , Adulto , Encéfalo/fisiopatología , Relación Dosis-Respuesta a Droga , Femenino , Análisis de Fourier , Dependencia de Heroína/rehabilitación , Humanos , Masculino , Dependencia de Morfina/rehabilitación , Oscilometría , Reflejo Pupilar/fisiología
17.
Cytogenet Cell Genet ; 91(1-4): 267-77, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11173868

RESUMEN

Age-related macular degeneration (AMD) is a multifactorial disorder affecting the visual system with a high prevalence among the elderly population but with no effective therapy available at present. To better understand the pathogenesis of this disorder, the identification of the genetic factors and the determination of their contribution to AMD is needed. Towards this goal, we are pursuing a strategy that makes use of the EST data processed in the UniGene database and aims at the generation of a comprehensive catalogue of genes preferentially active in the human retina. Subsequently, these genes will be systematically assessed in AMD. We performed a retina EST sampling and obtained a total of 673 clusters containing only retina ESTs as well as 568 clusters with at least 30% of the ESTs in each cluster originating from retina cDNA libraries. Of these, 180 representative EST clusters with varying retina and non-retina EST contents were analyzed for their in vitro expression. This approach identified 39 transcripts with retina-specific expression. One of these genes (C18orf2) mapping to chromosome 18 was further characterized. Multiple C18orf2 transcripts display a complex pattern of differential splicing in the human retina. The various isoforms encode hypothetical polypeptides with no homologies to known proteins or protein motifs.


Asunto(s)
Bases de Datos como Asunto , Etiquetas de Secuencia Expresada , Retina/metabolismo , Empalme Alternativo/genética , Secuencia de Aminoácidos , Clonación Molecular , Exones/genética , Perfilación de la Expresión Génica , Humanos , Intrones/genética , Datos de Secuencia Molecular , Familia de Multigenes/genética , Sistemas de Lectura Abierta/genética , Especificidad de Órganos , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , ARN Mensajero/análisis , ARN Mensajero/genética , Enfermedades de la Retina/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Alineación de Secuencia , Lugares Marcados de Secuencia
18.
Neuropsychobiology ; 40(1): 40-6, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10420100

RESUMEN

Memory loss and severe cognitive deficits in Alzheimer patients are supposed to be related to a reduction of acetylcholine as well as to central nervous deactivation. For the investigation of cholinergic deficits and deactivation, we used computer-assisted pupillometry. Cholinergic deficits caused by a particularly severe loss of cholinergic neurons may be responsible for cognitive and mnemonic performance deficits. The control of the pupillary diameter represents a balance between cholinergic and adrenergic innervation and is influenced directly or indirectly by central and autonomic nervous system inputs. Either of these systems could be affected in Alzheimer patients. A reduced innervation of the target muscle through neuronal cell death, axon retraction, reduced release, increased reuptake of altered amounts or function of neurotransmitter receptors seems to affect the pupillary response to cholinergic antagonists in Alzheimer patients. There is, however, no relationship between pupillary diameter and central deactivation, but between central nervous activation and pupillary oscillations which reflect the physiological corticodiencephalic activity, a relationship has to be assumed. Frequencies and amplitudes of pupillary oscillations measured by means of Fourier analysis are modulated corticodiencephalically. Therefore, Alzheimer patients were compared to healthy controls with respect to their pupillary diameters and responses to an acetylcholine antagonist. Twenty-nine patients, aged between 55 and 85 years, suffering from mild to moderate Alzheimer's disease (AD) and 29 normal controls of similar age (56-85 years) participated in the study. The cholinergic receptors of the pupil were blocked by the acetylcholine antagonist tropicamide. It could be assumed that the larger the pupillary dilatation, the larger the extent of cognitive deficits. Alzheimer patients show abnormal acetylcholine neurotransmission. Changes of pupillary diameter after instillation of 1 drop of 0.01% tropicamide solution were measured and Fourier analysis of pupillary oscillations was performed. Times of measurement were: 0 (baseline), 20, 40, 60, 80, and 100 min. After 4 min tropicamide was instilled. Forty min after the instillation of tropicamide into the left eye, the Alzheimer patients showed a pronounced dilatation of 41.57%. The dilatation in normal controls was 28.5%. Fourier analysis of pupillary oscillations (sum of frequency bands = power) demonstrated a marked deactivation (low amplitudes in low-frequency bands, but in contrast to our expectations no higher amplitudes in the higher frequency bands) in patients with AD which remained constant at all times of measurement. By means of discriminant analysis of pupillary diameter and pupillary oscillations (frequency band 0.00-1 Hz), 89. 7% were correctly predicted to be Alzheimer patients, 89% to be normal controls.


Asunto(s)
Enfermedad de Alzheimer/fisiopatología , Sistema Nervioso Central/fisiopatología , Midriáticos/administración & dosificación , Pupila/efectos de los fármacos , Tropicamida/administración & dosificación , Anciano , Estudios de Casos y Controles , Sistema Nervioso Central/efectos de los fármacos , Femenino , Análisis de Fourier , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas
19.
Wien Med Wochenschr ; 149(7): 162-6, 1999.
Artículo en Alemán | MEDLINE | ID: mdl-10413838

RESUMEN

The aim of the study was to answer the question if there are any differences in the central activation of different groups of psychosomatic patients and patients with eating disorders, which was measured by means of Fourier analysis of pupillary oscillations. A total of 132 patients (110 f, 22 m) with a mean age of 29.69 years (standard deviation: 9.9) participated in the study. In anorectic and bulimic patients high central activation was observed. Different groups of psychosomatic patients showed significant differences in their central nervous activation. In the group of subjects with the ICD-10 diagnosis F 41.3 (mixed anxiety disorders) the highest amplitudes was observed not only in the particular frequency bands but also in the total spectrum (power), which reflects high central activation. Reduced activation was found in subjects with somatoform autonomic function disorder of the upper and lower gastrointestinal tract (F 45.3). The measurement of central activation in psychosomatic disorders could have consequences for therapeutic interventions.


Asunto(s)
Anorexia Nerviosa/diagnóstico , Nivel de Alerta/fisiología , Bulimia/diagnóstico , Trastornos Psicofisiológicos/diagnóstico , Reflejo Pupilar/fisiología , Adulto , Anorexia Nerviosa/fisiopatología , Bulimia/fisiopatología , Corteza Cerebral/fisiopatología , Femenino , Análisis de Fourier , Humanos , Masculino , Vías Nerviosas/fisiopatología , Oscilometría/instrumentación , Trastornos Psicofisiológicos/fisiopatología , Valores de Referencia , Formación Reticular/fisiopatología , Procesamiento de Señales Asistido por Computador/instrumentación , Tálamo/fisiopatología
20.
Artif Organs ; 23(5): 447-52, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10378940

RESUMEN

The use of electrical stimulation for denervated muscles is still considered to be a controversial issue by many rehabilitation facilities and medical professionals because prior clinical experience has shown that treating denervated muscle tissue using exponential current over a long time period constitutes an impossible task. Despite this fact, we managed to evoke tetanic contractions in denervated muscle using a long duration stimulation with anatomically shaped electrodes and sufficiently high amplitudes. The pulse amplitudes, which were being used for this purpose, exceeded by far the MED-GV and EC regulations (300 mJ/impulse). For this reason, an application has recently been submitted to have the EC regulations changed accordingly. It takes a tetanic contraction to achieve the desired muscle fiber tension, constituting a hypertrophic stimulus. It is also an appropriate means of exercise, which is capable of creating the metabolic and structural conditions needed (e.g, increased mitochondrial volume and capillary density) to obtain satisfactory muscle performance. With patients suffering from a complete spinal cord injury at level D12/L1, having motor and sensory loss in both lower extremities, we were able to train denervated muscle using long-duration stimulation, evoking single muscle contractions at first, soon followed by tetanic contractions against gravity. To increase the efficacy of this functional electrical stimulation (FES) strengthening program, we used ankle weights. With daily FES training over a period of 1-2 years, denervated muscle was exercised until it produced torques between 16 and 38 Nm in the m. quadriceps. With that muscle force, it is possible to stand up from a sitting position in parallel bars. Our results show that denervated muscle in humans is indeed trainable and can perform functional activities with FES. Furthermore, this method of stimulation can assist in decubitus prevention and significantly improve the mobility of paraplegics.


Asunto(s)
Terapia por Estimulación Eléctrica/métodos , Músculo Esquelético/inervación , Paraplejía/rehabilitación , Postura/fisiología , Soporte de Peso/fisiología , Capilares/ultraestructura , Terapia por Estimulación Eléctrica/instrumentación , Electrodos , Ejercicio Físico/fisiología , Gravitación , Humanos , Mitocondrias Musculares/ultraestructura , Contracción Muscular/fisiología , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/fisiología , Fibras Musculares Esqueléticas/ultraestructura , Músculo Esquelético/anatomía & histología , Músculo Esquelético/metabolismo , Úlcera por Presión/prevención & control , Traumatismos de la Médula Espinal/rehabilitación , Torque , Levantamiento de Peso/fisiología
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