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1.
J Clin Med ; 13(13)2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38999395

RESUMEN

Monitoring the tumor margins of basal cell carcinomas is still a challenge in everyday clinical practice. Usually, the clinical margins of the tumor are marked by the naked eye or, even better, with dermoscopy before surgery and then examined in detail after the operation using histological examination. In order to achieve tumor freedom, several surgical steps are sometimes necessary, meaning that patients spend longer periods in hospital and the healthcare system is burdened more as a result. One way to improve this is the one-stop shop method, which requires precise diagnostics and margin marking before and during surgery so that tumor freedom can be achieved after just one surgery. For this reason, the current status of the diagnosis and treatment of basal cell carcinomas before and after surgery is to be examined following extensive literature research using devices and methods that have already been tested in order to determine how a simplified process of tumor margin control of basal cell carcinomas can be made possible both in vivo and ex vivo.

3.
Cardiovasc Diagn Ther ; 12(4): 426-435, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36033224

RESUMEN

Background: Fabry disease (FD) is a multi-organ disorder associated with severe physical and psychological impairments, particularly in adulthood. To date, comprehensive data on the psychological burden of FD are lacking. The present study assessed quality of life (QOL) in a representative cohort of adults with FD. Methods: Patient-reported outcome measures were retrospectively analyzed in 86 adults with FD (49.6±16.6 years; 62.8% female) and compared to adults with congenital heart defects (ACHD) which is another lifelong disease and affliction. QOL was assessed using the European Quality of Life 5 Dimensions 5 Levels questionnaire (EQ-5D-5L). Results: Subjects affected by FD reported an overall reduced QOL (EQ-VAS: 71.8±20.0). Most frequently reported complaints occurred within the dimensions pain/discomfort (69.7%), daily activities (48.9%) and anxiety/depression (45.4%). Compared to ACHD, individuals with FD scored significantly lower in the areas of pain/discomfort, usual activities and mobility (all P<0.05). Older age and female sex were particularly associated with diminished QOL (P=0.05). Conclusions: Patients with FD are at high risk for impaired QOL. They require additional support to cope with disease-related challenges. Increased attention should be directed towards improving their subjective well-being to potentially increase their QOL and long-term health outcomes.

4.
RNA Biol ; 7(6): 803-11, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21045551

RESUMEN

In yeast mitochondria the DEAD-box helicase Mss116p is essential for respiratory growth by acting as group I and group II intron splicing factor. Here we provide the first structure-based insights into how Mss116p assists RNA folding in vivo. Employing an in vivo chemical probing technique, we mapped the structure of the ai5γ group II intron in different genetic backgrounds to characterize its intracellular fold. While the intron adopts the native conformation in the wt yeast strain, we found that the intron is able to form most of its secondary structure, but lacks its tertiary fold in the absence of Mss116p. This suggests that ai5γ is largely unfolded in the mss116-knockout strain and requires the protein at an early step of folding. Notably, in this unfolded state misfolded substructures have not been observed. As most of the protein-induced conformational changes are located within domain D1, Mss116p appears to facilitate the formation of this largest domain, which is the scaffold for docking of other intron domains. These findings suggest that Mss116p assists the ordered assembly of the ai5γ intron in vivo.


Asunto(s)
ARN Helicasas DEAD-box/metabolismo , ARN/metabolismo , Levaduras/enzimología , Levaduras/genética , Dominio Catalítico , Intrones/genética , Mitocondrias/genética , Mitocondrias/metabolismo , Conformación de Ácido Nucleico , ARN/química
5.
RNA Biol ; 5(1): 30-40, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18388495

RESUMEN

Bacterial small RNAs (sRNAs) are non-coding RNAs that regulate gene expression enabling cells to adapt to various growth conditions. Assuming that most RNAs require proteins to exert their activities, we purified and identified sRNA-binding factors via affinity chromatography and mass spectrometry. We consistently obtained RNA polymerase betasubunit, host factor Hfq and ribosomal protein S1 as sRNA-binding proteins in addition to several other factors. Most importantly, we observed that RNA polymerase not only binds several sRNAs but also reacts with them, both cleaving and extending the RNAs at their 3' ends. The fact that the RNA polymerase reacts with sRNAs maps their interaction site to the active centre cleft of the enzyme and shows that it takes RNAs as template to perform RNA-dependent RNA polymerase activity. We further performed genomic SELEX to isolate RNA polymerase-binding RNAs and obtained a large number of E. coli sequences binding with high affinity to this enzyme. In vivo binding of some of the RNAs to the RNA polymerase was confirmed via co-immunoprecipitation in cell extracts prepared from different growth conditions. Our observations show that RNA polymerase is able to bind and react with many different RNAs and we suggest that RNAs are involved in transcriptional regulation more frequently than anticipated.


Asunto(s)
ARN Polimerasas Dirigidas por ADN/metabolismo , Proteínas de Escherichia coli/metabolismo , ARN Bacteriano/metabolismo , Proteínas de Unión al ARN/metabolismo , Regiones no Traducidas 3' , Proteínas de Escherichia coli/aislamiento & purificación , Regulación Bacteriana de la Expresión Génica , Unión Proteica , Proteínas de Unión al ARN/aislamiento & purificación
6.
Nucleic Acids Res ; 35(4): 1257-69, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17267410

RESUMEN

The E. coli protein StpA has RNA annealing and strand displacement activities and it promotes folding of RNAs by loosening their structures. To understand the mode of action of StpA, we analysed the relationship of its RNA chaperone activity to its RNA-binding properties. For acceleration of annealing of two short RNAs, StpA binds both molecules simultaneously, showing that annealing is promoted by crowding. StpA binds weakly to RNA with a preference for unstructured molecules. Binding of StpA to RNA is strongly dependent on the ionic strength, suggesting that the interactions are mainly electrostatic. A mutant variant of the protein, with a glycine to valine change in the nucleic-acid-binding domain, displays weaker RNA binding but higher RNA chaperone activity. This suggests that the RNA chaperone activity of StpA results from weak and transient interactions rather than from tight binding to RNA. We further discuss the role that structural disorder in proteins may play in chaperoning RNA folding, using bioinformatic sequence analysis tools, and provide evidence for the importance of conformational disorder and local structural preformation of chaperone nucleic-acid-binding sites.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Proteínas de Escherichia coli/metabolismo , Chaperonas Moleculares/metabolismo , ARN/química , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Escherichia coli/genética , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Exones , Genómica , Chaperonas Moleculares/química , Chaperonas Moleculares/genética , Mutación , Conformación de Ácido Nucleico , Unión Proteica , Estructura Terciaria de Proteína , ARN/metabolismo , Precursores del ARN/química , Precursores del ARN/metabolismo , ARN Mensajero/química , ARN Mensajero/metabolismo
7.
RNA Biol ; 4(3): 118-30, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18347437

RESUMEN

RNA molecules face difficulties when folding into their native structures. In the cell, proteins can assist RNAs in reaching their functionally active states by binding and stabilizing a specific structure or, in a quite opposite way, by interacting in a non-specific manner. These proteins can either facilitate RNA-RNA interactions in a reaction termed RNA annealing, or they can resolve non-functional inhibitory structures. The latter is defined as "RNA chaperone activity" and is the main topic of this review. Here we define RNA chaperone activity in a stringent way and we review those proteins for which RNA chaperone activity has been clearly demonstrated. These proteins belong to quite diverse families such as hnRNPs, histone-like proteins, ribosomal proteins, cold shock domain proteins and viral nucleocapsid proteins. DExD/H-box containing RNA helicases are discussed as a special family of enzymes that restructure RNA or RNPs in an ATP-dependent manner. We further address the different mechanisms RNA chaperones might use to promote folding including the recently proposed theory of protein disorder as a key element in triggering RNA-protein interactions. Finally, we present a new website for proteins with RNA chaperone activity which compiles all the information on these proteins with the perspective to promote the understanding of their activity.


Asunto(s)
Chaperonas Moleculares/química , Chaperonas Moleculares/fisiología , ARN Helicasas/química , ARN Helicasas/fisiología , ARN/química , ARN/metabolismo , Animales , Humanos , Chaperonas Moleculares/clasificación , Conformación de Ácido Nucleico , ARN/fisiología , ARN Helicasas/clasificación
8.
RNA ; 11(7): 1084-94, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15928345

RESUMEN

Ro ribonucleoprotein (RNP) complexes are composed of one molecule of a small noncoding cytoplasmic RNA, termed Y RNA, and the two proteins Ro60 and La. Additional proteins such as hnRNP I, hnRNP K, or nucleolin have recently been shown to be associated with subpopulations of Y RNAs. Ro RNPs appear to be localized in the cytoplasm of all higher eukaryotic cells but their functions have remained elusive. To shed light on possible functions of Ro RNPs, we tested protein components of these complexes for RNA chaperone properties employing two in vitro chaperone assays and additionally an in vivo chaperone assay. In these assays the splicing activity of a group I intron is measured. La showed pronounced RNA chaperone activity in the cis-splicing assay in vitro and also in vivo, whereas no activity was seen in the trans-splicing assay in vitro. Both hnRNP I and hnRNP K exhibited strong chaperone activity in the two in vitro assays, however, proved to be cytotoxic in the in vivo assay. No chaperone activity was observed for Ro60 in vitro and a moderate activity was detected in vivo. In vitro chaperone activities of La and hnRNP I were completely inhibited upon binding of Y RNA. Taken together, these data suggest that the Ro RNP components La, hnRNP K, and hnRNP I possess RNA chaperone activity, while Ro60-Y RNA complexes might function as transporters, bringing other Y RNA binding proteins to their specific targets.


Asunto(s)
Autoantígenos/metabolismo , Chaperonas Moleculares/metabolismo , ARN Citoplasmático Pequeño/metabolismo , ARN/metabolismo , Ribonucleoproteínas/metabolismo , Autoantígenos/química , Autoantígenos/genética , Autoantígenos/aislamiento & purificación , Citoplasma/metabolismo , Ribonucleoproteínas Nucleares Heterogéneas/química , Ribonucleoproteínas Nucleares Heterogéneas/clasificación , Ribonucleoproteínas Nucleares Heterogéneas/genética , Ribonucleoproteínas Nucleares Heterogéneas/aislamiento & purificación , Ribonucleoproteínas Nucleares Heterogéneas/metabolismo , Humanos , Técnicas In Vitro , Intrones , Mutación , Unión Proteica , ARN Citoplasmático Pequeño/química , ARN Citoplasmático Pequeño/genética , ARN Citoplasmático Pequeño/aislamiento & purificación , Proteínas Recombinantes/química , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Ribonucleoproteínas/química , Ribonucleoproteínas/genética , Ribonucleoproteínas/aislamiento & purificación , Radioisótopos de Azufre/metabolismo , Trans-Empalme , Transcripción Genética , Antígeno SS-B
9.
Nucleic Acids Res ; 33(7): 2280-9, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15849314

RESUMEN

Proteins with RNA chaperone activity are able to promote folding of RNA molecules by loosening their structure. This RNA unfolding activity is beneficial when resolving misfolded RNA conformations, but could be detrimental to RNAs with low thermodynamic stability. In order to test this idea, we constructed various RNAs with different structural stabilities derived from the thymidylate synthase (td) group I intron and measured the effect of StpA, an Escherichia coli protein with RNA chaperone activity, on their splicing activity in vivo and in vitro. While StpA promotes splicing of the wild-type td intron and of mutants with wild-type-like stability, splicing of mutants with a lower structural stability is reduced in the presence of StpA. In contrast, splicing of an intron mutant, which is not destabilized but which displays a reduced population of correctly folded RNAs, is promoted by StpA. The sensitivity of an RNA towards StpA correlates with its structural stability. By lowering the temperature to 25 degrees C, a temperature at which the structure of these mutants becomes more stable, StpA is again able to stimulate splicing. These observations clearly suggest that the structural stability of an RNA determines whether the RNA chaperone activity of StpA is beneficial to folding.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Proteínas de Escherichia coli/metabolismo , Intrones , Chaperonas Moleculares/metabolismo , Estabilidad del ARN , ARN/química , Secuencia de Bases , Proteínas de Unión al ADN/genética , Proteínas de Escherichia coli/genética , Chaperonas Moleculares/genética , Datos de Secuencia Molecular , Mutación , Conformación de Ácido Nucleico , Temperatura
10.
Ren Fail ; 26(3): 279-87, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15354978

RESUMEN

BACKGROUND: Cardiovascular disease is a major problem in patients with chronic renal failure leading to increased mortality. Several infectious agents have been implicated to be associated with atherosclerosis. We were interested to evaluate whether there is a correlation between a past infection with Chlamydia pneumoniae (Cpn), Helicobacter pylori (Hp) or cytomegalovirus (CMV) and the manifestation of a symptomatic atherosclerotic disease in patients with endstage renal failure. METHODS AND RESULTS: Patients (n=267) on hemodialysis were investigated. In 101 patients with an apparent atherosclerotic disease (case group) increased IgA levels against Cpn were found (p < or = 0.0001 vs. controls; n=33). Nearly 45% of the case group had a history of myocardial infarction (MI) (p < or = 0.0001). Prior stroke was found in about 30% of patients in the case group (p < or = 0.002). Elevated CRP levels were identified as an independent risk factor for atherosclerosis in all groups. IgA seropositivity against Cpn correlated with elevated CRP values for all atherosclerotic patients (p < or = 0.001), especially in the group of patients with MI (p < or = 0.019) and peripheral vascular disease (p < or = 0.005). There was no correlation between CMV (IgG, IgM) or Hp (IgA, IgG) seropositivity and atherosclerotic disease. CONCLUSION: IgA seropositivity for Cpn and elevated CRP values but not Hp or CMV was associated with an increased rate of symptomatic atherosclerotic manifestations as MI, stroke, cerebral or peripheral atherosclerosis in patients with endstage renal disease on hemodialysis.


Asunto(s)
Arteriosclerosis/microbiología , Proteína C-Reactiva/metabolismo , Infecciones por Chlamydophila/epidemiología , Infecciones por Citomegalovirus/epidemiología , Infecciones por Helicobacter/epidemiología , Fallo Renal Crónico/complicaciones , Diálisis Renal , Anciano , Arteriosclerosis/epidemiología , Estudios de Casos y Controles , Chlamydophila pneumoniae/inmunología , Femenino , Helicobacter pylori/inmunología , Humanos , Inmunoglobulina A/inmunología , Fallo Renal Crónico/terapia , Modelos Logísticos , Masculino , Infarto del Miocardio/epidemiología , Oportunidad Relativa , Factores de Riesgo , Accidente Cerebrovascular/epidemiología
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