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1.
Psychophysiology ; : e14633, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38873807

RESUMEN

Event-related potentials (ERPs) have been used with the concealed information test (CIT) to detect concealed recognition of specific stimuli (i.e., "probes"). While most research has focused on the P300 component, which is larger for infrequent probes than for frequent control stimuli (i.e., "irrelevants"), some studies have investigated an earlier ERP component, the anterior N2, with mixed results. Although some studies have reported a larger anterior N2 for probes than irrelevants (N2 enhancement), other studies, including our own, have not found such an effect. The present study aimed to replicate and extend our previous findings using the same CIT paradigm and measurement parameters. Results of Bayesian analyses show strong evidence against the hypothesis of anterior N2 enhancement by probes, replicating our previous work. Bayesian analyses also show strong evidence against the hypothesis of N2 enhancement for the three components revealed by a temporal principal component analysis (PCA) conducted to disentangle potentially overlapping ERP effects. In conclusion, whereas the CIT has shown promise in detecting recognition of specific information, anterior N2 enhancement cannot be used as an electrophysiological measure of concealed information across CIT paradigms.

2.
Nanoscale ; 16(22): 10751-10759, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38747099

RESUMEN

Break-junction techniques provide the possibility to study electric and thermoelectric properties of single-molecule junctions in great detail. These techniques rely on the same principle of controllably breaking metallic contacts in order to create single-molecule junctions, whilst keeping track of the junction's conductance. Here, we compare results from mechanically controllable break junction (MCBJ) and scanning tunneling microscope (STM) methods, while characterizing conductance properties of the same novel mechanosensitive para- and meta-connected naphtalenophane compounds. In addition, thermopower measurements are carried out for both compounds using the STM break junction (STM-BJ) technique. For the conductance experiments, the same data processing using a clustering analysis is performed. We obtain to a large extent similar results for both methods, although values of conductance and stretching lengths for the STM-BJ technique are slightly larger in comparison with the MCBJ. STM-BJ thermopower experiments show similar Seebeck coefficients for both compounds. An increase in the Seebeck coefficient is revealed, whilst the conductance decreases, after which it saturates at around 10 µV K-1. This phenomenon is studied theoretically using a tight binding model. It shows that changes of molecule-electrode electronic couplings combined with shifts of the resonance energies explain the correlated behavior of conductance and Seebeck coefficient.

3.
Int J Med Sci ; 20(1): 70-78, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36619233

RESUMEN

Background: Chest compressions are the basis of cardiopulmonary resuscitation (CPR), and high-quality chest compressions can improve survival rate in patients with out-of-hospital cardiac arrest. Although many efforts have been made to improve the quality of CPR in inexperienced adults, the results are still not high, especially during emergencies. The primary purpose of this study is to investigate whether a brief instructional chest compression-only CPR video could improve chest compression quality in inexperienced adults. Methods: One hundred adults with no CPR experience (age: 20.28 ± 2.28 years; women: 50, men: 50) participated in this study. Participants completed body composition and handgrip strength measurements, and performed two CPR quality tests on the Laerdal® Little Anne QCPR Manikin, namely without video-CPR (WV-CPR) and video-CPR (V-CPR). The WV-CPR quality test was performed first. After 2 minutes of continuous chest compression, the participants rested for 10 seconds and repeated 3 cycles (phase 1, phase 2, and phase 3). After resting for more than 72 hours, V-CPR quality test was conducted. During the V-CPR with video intervention, the participants also continued to compress the chest for 2 minutes, and then rested for 10 seconds, repeating 3 cycles. Results: In phase 1, compared with WV-CPR, the V-CPR has a significant increase (p < 0.001) in chest compression fraction (CCF) (56.31 ± 33.22% vs. 41.82 ± 32.30%) and percent of correct compression rate (PCCR) (96.17 ± 8.45% vs. 26.31 ± 37.55%). In addition, the V-CPR has significantly lower (p < 0.001) chest compression rate (CCR) (110.85 ± 2.40 cpm vs. 128.86 ± 24.52 cpm) and rating of perceived exertion (RPE) (11.89 ± 2.25 vs. 12.87 ± 2.25). For phases 2 through 3, V-CPR and WV-CPR achieved significant differences in CCF, CCD, CCR, PCCR, and RPE (p < 0.01). There were significant differences (p < 0.05) in CCF, CCD, chest compression rebound rate, and RPE among the different administration stages of both WV-CPR and V-CPR. Conclusions: The results of this study revealed that a brief instructional chest compression-only CPR video could improve chest compression quality for inexperienced adults by reducing fatigue and CCR, and increasing CCF and PCCR.


Asunto(s)
Reanimación Cardiopulmonar , Paro Cardíaco Extrahospitalario , Adolescente , Adulto , Femenino , Humanos , Masculino , Adulto Joven , Reanimación Cardiopulmonar/métodos , Fatiga , Fuerza de la Mano , Tórax , Maniquíes
4.
EMBO Mol Med ; 15(2): e16525, 2023 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-36645044

RESUMEN

Iron accumulation causes cell death and disrupts tissue functions, which necessitates chelation therapy to reduce iron overload. However, clinical utilization of deferoxamine (DFO), an iron chelator, has been documented to give rise to systemic adverse effects, including ocular toxicity. This study provided the pathogenic and molecular basis for DFO-related retinopathy and identified retinal pigment epithelium (RPE) as the target tissue in DFO-related retinopathy. Our modeling demonstrated the susceptibility of RPE to DFO compared with the neuroretina. Intriguingly, we established upregulation of hypoxia inducible factor (HIF) 2α and mitochondrial deficit as the most prominent pathogenesis underlying the RPE atrophy. Moreover, suppressing hyperactivity of HIF2α and preserving mitochondrial dysfunction by α-ketoglutarate (AKG) protects the RPE against lesions both in vitro and in vivo. This supported our observation that AKG supplementation alleviates visual impairment in a patient undergoing DFO-chelation therapy. Overall, our study established a significant role of iron deficiency in initiating DFO-related RPE atrophy. Inhibiting HIF2α and rescuing mitochondrial function by AKG protect RPE cells and can potentially ameliorate patients' visual function.


Asunto(s)
Quelantes del Hierro , Enfermedades de la Retina , Humanos , Quelantes del Hierro/efectos adversos , Muerte Celular , Atrofia/inducido químicamente
5.
Artículo en Inglés | MEDLINE | ID: mdl-36361295

RESUMEN

The purpose of this study is to explore whether religious tourism activities can create a safe leisure environment and improve the well-being of the elderly during the COVID-19 pandemic, with the participants in the Baishatun Mazu pilgrimage in Taiwan as the subjects of this study. A mixed research method was used. First, statistical software and the Pearson product-moment correlation coefficient were used to analyze the data. Then the respondents' opinions were collected. Finally, a multivariate analysis method was used to discuss the results of analysis. The findings showed that the elderly respondents thought that the epidemic prevention information and leisure space planning for the pilgrimage made them feel secure. The elderly believed the scenery, religious atmosphere, and commodities en route could reduce the perception of environmental risks to tourists, relieve pressure on the brain, and increase social opportunities. Therefore, the friendlier the leisure environment around the pilgrimage, the greater the leisure satisfaction among the elderly respondents. The happier the elderly felt, the less they considered the concentration of airborne contaminants, including viruses. The better their physical and mental health was, the less likely they were to want to ask for religious goods.


Asunto(s)
COVID-19 , Satisfacción Personal , Humanos , Anciano , Salud Mental , COVID-19/epidemiología , Turismo , Pandemias , Actividades Recreativas/psicología
6.
Chem Sci ; 13(27): 8017-8024, 2022 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-35919422

RESUMEN

Intra- and intermolecular interactions are dominating chemical processes, and their concerted interplay enables complex nonequilibrium states like life. While the responsible basic forces are typically investigated spectroscopically, a conductance measurement to probe and control these interactions in a single molecule far out of equilibrium is reported here. Specifically, by separating macroscopic metal electrodes, two π-conjugated, bridge-connected porphyrin decks are peeled off on one side, but compressed on the other side due to the covalent mechanical fixation. We observe that the conductance response shows an exceptional exponential rise by two orders of magnitude in individual breaking events during the stretching. Theoretical studies atomistically explain the measured conductance behavior by a mechanically activated increase in through-bond transport and a simultaneous strengthening of through-space coupling. Our results not only reveal the various interacting intramolecular transport channels in a molecular set of levers, but also the molecules' potential to serve as molecular electro-mechanical sensors and switches.

7.
Phys Rev Lett ; 128(14): 147701, 2022 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-35476482

RESUMEN

Probing the universal low-temperature magnetic-field scaling of Kondo-correlated quantum dots via electrical conductance has proved to be experimentally challenging. Here, we show how to probe this in nonlinear thermocurrent spectroscopy applied to a molecular quantum dot in the Kondo regime. Our results demonstrate that the bias-dependent thermocurrent is a sensitive probe of universal Kondo physics, directly measures the splitting of the Kondo resonance in a magnetic field, and opens up possibilities for investigating nanosystems far from thermal and electrical equilibrium.

8.
Mol Ther ; 30(4): 1407-1420, 2022 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-35150888

RESUMEN

Mutations in rhodopsin (RHO) are the most common causes of autosomal dominant retinitis pigmentosa (adRP), accounting for 20% to 30% of all cases worldwide. However, the high degree of genetic heterogeneity makes development of effective therapies cumbersome. To provide a universal solution to RHO-related adRP, we devised a CRISPR-based, mutation-independent gene ablation and replacement (AR) compound therapy carried by a dual AAV2/8 system. Moreover, we developed a novel hRHOC110R/hRHOWT humanized mouse model to assess the AR treatment in vivo. Results show that this humanized RHO mouse model exhibits progressive rod-cone degeneration that phenocopies hRHOC110R/hRHOWT patients. In vivo transduction of AR AAV8 dual vectors remarkably ablates endogenous RHO expression and overexpresses exogenous WT hRHO. Furthermore, the administration of AR during adulthood significantly hampers photoreceptor degeneration both histologically and functionally for at least 6 months compared with sole gene replacement or surgical trauma control. This study demonstrates the effectiveness of AR treatment of adRP in the human genomic context while revealing the feasibility of its application for other autosomal dominant disorders.


Asunto(s)
Degeneración Retiniana , Retinitis Pigmentosa , Animales , Modelos Animales de Enfermedad , Genes Dominantes , Terapia Genética/métodos , Humanos , Ratones , Mutación , Degeneración Retiniana/genética , Retinitis Pigmentosa/genética , Retinitis Pigmentosa/patología , Retinitis Pigmentosa/terapia , Rodopsina/genética , Rodopsina/metabolismo
9.
Hum Mol Genet ; 31(14): 2438-2451, 2022 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-35195241

RESUMEN

Retinitis pigmentosa (RP) is caused by one of many possible gene mutations. The National Institutes of Health recommends high daily doses of vitamin A palmitate for RP patients. There is a critical knowledge gap surrounding the therapeutic applicability of vitamin A to patients with the different subtypes of the disease. Here, we present a case report of a patient with RP caused by a p.D190N mutation in Rhodopsin (RHO) associated with abnormally high quantitative autofluorescence values after long-term vitamin A supplementation. We investigated the effects of vitamin A treatment strategy on RP caused by the p.D190N mutation in RHO by exposing Rhodopsin p.D190N (RhoD190N/+) and wild-type (WT) mice to experimental vitamin A-supplemented and standard control diets. The patient's case suggests that the vitamin A treatment strategy should be further studied to determine its effect on RP caused by p.D190N mutation in RHO and other mutations. Our mouse experiments revealed that RhoD190N/+ mice on the vitamin A diet exhibited higher levels of autofluorescence and lipofuscin metabolites compared to WT mice on the same diet and isogenic controls on the standard control diet. Vitamin A supplementation diminished photoreceptor function in RhoD190N/+ mice while preserving cone response in WT mice. Our findings highlight the importance of more investigations into the efficacy of clinical treatments like vitamin A for patients with certain genetic subtypes of disease and of genotyping in the precision care of inherited retinal degenerations.


Asunto(s)
Degeneración Retiniana , Retinitis Pigmentosa , Animales , Suplementos Dietéticos , Ratones , Mutación , Degeneración Retiniana/genética , Retinitis Pigmentosa/tratamiento farmacológico , Retinitis Pigmentosa/genética , Retinitis Pigmentosa/metabolismo , Rodopsina/genética , Rodopsina/metabolismo , Vitamina A
10.
Nanoscale ; 14(3): 984-992, 2022 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-34989747

RESUMEN

The possibility to study quantum interference phenomena at ambient conditions is an appealing feature of molecular electronics. By connecting two porphyrins in a cofacial cyclophane, we create an attractive platform for mechanically controlling electric transport through the intramolecular extent of π-orbital overlap of the porphyrins facing each other and through the angle of xanthene bridges with regard to the porphyrin planes. We analyze theoretically the evolution of molecular configurations in the pulling process and the corresponding changes in electric conduction by combining density functional theory (DFT) with Landauer scattering theory of phase-coherent elastic transport. Predicted conductances during the stretching process show order of magnitude variations caused by two robust destructive quantum interference features that span through the whole electronic gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO). Mechanically-controlled break junction (MCBJ) experiments at room temperature verify the mechanosensitive response of the molecular junctions. During the continuous stretching of the molecule, they show conductance variations of up to 1.5 orders of magnitude over single breaking events. Uncommon triple- and quadruple-frequency responses are observed in periodic electrode modulation experiments with amplitudes of up to 10 Å. This further confirms the theoretically predicted double transmission dips caused by the spatial and energetic rearrangement of molecular orbitals, with contributions from both through-space and through-bond transport.

11.
Nano Lett ; 21(22): 9715-9719, 2021 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-34766782

RESUMEN

Single molecules are nanoscale thermodynamic systems with few degrees of freedom. Thus, the knowledge of their entropy can reveal the presence of microscopic electron transfer dynamics that are difficult to observe otherwise. Here, we apply thermocurrent spectroscopy to directly measure the entropy of a single free radical molecule in a magnetic field. Our results allow us to uncover the presence of a singlet to triplet transition in one of the redox states of the molecule, not detected by conventional charge transport measurements. This highlights the power of thermoelectric measurements which can be used to determine the difference in configurational entropy between the redox states of a nanoscale system involved in conductance without any prior assumptions about its structure or microscopic dynamics.


Asunto(s)
Entropía , Transporte de Electrón , Análisis Espectral , Termodinámica
12.
J Am Chem Soc ; 143(34): 13944-13951, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34424713

RESUMEN

Quantum interference (QI) of electron waves passing through a single-molecule junction provides a powerful means to influence its electrical properties. Here, we investigate the correlation between substitution pattern, conductance, and mechanosensitivity in [2.2]paracyclophane (PCP)-based molecular wires in a mechanically controlled break junction experiment. The effect of the meta versus para connectivity in both the central PCP core and the phenyl ring connecting the terminal anchoring group is studied. We find that the meta-phenyl-anchored PCP yields such low conductance levels that molecular features cannot be resolved; in the case of para-phenyl-coupled anchoring, however, large variations in conductance values for modulations of the electrode separation occur for the pseudo-para-coupled PCP core, while this mechanosensitivity is absent for the pseudo-meta-PCP core. The experimental findings are interpreted in terms of QI effects between molecular frontier orbitals by theoretical calculations based on density functional theory and the Landauer formalism.

13.
Int J Mol Sci ; 22(15)2021 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-34360834

RESUMEN

Achromatopsia is characterized by amblyopia, photophobia, nystagmus, and color blindness. Previous animal models of achromatopsia have shown promising results using gene augmentation to restore cone function. However, the optimal therapeutic window to elicit recovery remains unknown. Here, we attempted two rounds of gene augmentation to generate recoverable mouse models of achromatopsia including a Cnga3 model with a knock-in stop cassette in intron 5 using Easi-CRISPR (Efficient additions with ssDNA inserts-CRISPR) and targeted embryonic stem (ES) cells. This model demonstrated that only 20% of CNGA3 levels in homozygotes derived from target ES cells remained, as compared to normal CNGA3 levels. Despite the low percentage of remaining protein, the knock-in mouse model continued to generate normal cone phototransduction. Our results showed that a small amount of normal CNGA3 protein is sufficient to form "functional" CNG channels and achieve physiological demand for proper cone phototransduction. Thus, it can be concluded that mutating the Cnga3 locus to disrupt the functional tetrameric CNG channels may ultimately require more potent STOP cassettes to generate a reversible achromatopsia mouse model. Our data also possess implications for future CNGA3-associated achromatopsia clinical trials, whereby restoration of only 20% functional CNGA3 protein may be sufficient to form functional CNG channels and thus rescue cone response.


Asunto(s)
Defectos de la Visión Cromática/genética , Canales Catiónicos Regulados por Nucleótidos Cíclicos/genética , Modelos Animales de Enfermedad , Edición Génica , Mutación , Animales , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Defectos de la Visión Cromática/metabolismo , Técnicas de Sustitución del Gen , Ratones , Células Fotorreceptoras Retinianas Conos/metabolismo , Células Fotorreceptoras Retinianas Conos/fisiología
14.
Nat Nanotechnol ; 16(4): 426-430, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33649585

RESUMEN

Theoretical studies suggest that mastering the thermocurrent through single molecules can lead to thermoelectric energy harvesters with unprecedentedly high efficiencies.1-6 This can be achieved by engineering molecule length,7 optimizing the tunnel coupling strength of molecules via chemical anchor groups8 or by creating localized states in the backbone with resulting quantum interference features.4 Empirical verification of these predictions, however, faces considerable experimental challenges and is still awaited. Here we use a novel measurement protocol that simultaneously probes the conductance and thermocurrent flow as a function of bias voltage and gate voltage. We find that the resulting thermocurrent is strongly asymmetric with respect to the gate voltage, with evidence of molecular excited states in the thermocurrent Coulomb diamond maps. These features can be reproduced by a rate-equation model only if it accounts for both the vibrational coupling and the electronic degeneracies, thus giving direct insight into the interplay of electronic and vibrational degrees of freedom, and the role of spin entropy in single molecules. Overall these results show that thermocurrent measurements can be used as a spectroscopic tool to access molecule-specific quantum transport phenomena.

15.
J Org Chem ; 85(23): 15072-15081, 2020 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-33166468

RESUMEN

Porphyrin cyclophane 1, consisting of two rigidly fixed but still movable cofacial porphyrins and exposing acetate-masked thiols in opposed directions of the macrocycle, is designed, synthesized, and characterized. The functional cyclophane 1, as pioneer of mechanosensitive 3D materials, forms stable single-molecule junctions in a mechanically controlled break-junction setup. Its reliable integration in a single-molecule junction is a fundamental prerequisite to explore the potential of these structures as mechanically triggered functional units and devices.

16.
Materials (Basel) ; 13(10)2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32429266

RESUMEN

We fabricated large-area atomically thin MoS2 layers through the direct transformation of crystalline molybdenum trioxide (MoO3) by sulfurization at relatively low temperatures. The obtained MoS2 sheets are polycrystalline (~10-20 nm single-crystal domain size) with areas of up to 300 × 300 µm2, 2-4 layers in thickness and show a marked p-type behavior. The synthesized films are characterized by a combination of complementary techniques: Raman spectroscopy, X-ray diffraction, transmission electron microscopy and electronic transport measurements.

17.
Sci Total Environ ; 703: 135488, 2020 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-31757555

RESUMEN

The hepatic toxicity of vinyl chloride monomer (VCM) has often been reported, but few studies have assessed insulin resistance or adipose tissue dysfunction. We analyzed the chronic health effects of moderate exposure to VCM on factory workers in Taiwan. Data were collected from personal air samples, urine samples, and immunohistochemical (IHC) examinations of 122 recruited voluntary participants. Air samples were analyzed to assess personal levels of exposure to VCM and ethylene dichloride (EDC). Urine samples were collected from each worker before they started and after they finished their daily shift. Urinary thiodiglycolic acid (TDGA) levels were analyzed using high-performance liquid chromatography-tandem mass spectrometry (HPLC/MS/MS). IHC examinations included liver function and serum adipokine level tests for insulin resistance. Consequently, the participants included for the final analysis were 113. After confounders had been adjusted for, the airborne VCM concentration significantly (P = 0.043) correlated with pre-shift urinary TDGA levels (ß = 0.194). A multivariate analysis showed a significant (P = 0.013) inverse correlation between the adiponectin:leptin ratio and the airborne VCM concentration (ß = -0.283), which means that exposure to VCM might increase the risk of insulin resistance and adiponectin abnormalities. We hypothesized that pre-shift urinary TDGA levels can be used as exposure biomarkers for the exposure of workers to VCM.


Asunto(s)
Adiponectina/metabolismo , Contaminantes Atmosféricos/toxicidad , Exposición por Inhalación/análisis , Leptina/metabolismo , Exposición Profesional/análisis , Cloruro de Vinilo/toxicidad , Biomarcadores/metabolismo , Taiwán
18.
Hum Mol Genet ; 28(20): 3475-3485, 2019 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-31518400

RESUMEN

Hypoxia associated with the high metabolic demand of rods has been implicated in the pathology of age-related macular degeneration (AMD), the most common cause of adult blindness in the developed world. The majority of AMD-associated severe vision loss cases are due to exudative AMD, characterized by neovascularization. To further investigate the causes and histopathology of exudative AMD, we conditionally induced hypoxia in a novel preclinical AMD model (Pde6gcreERT2/+;Vhl-/-) by targeting Vhl and used multimodal imaging and immunohistochemistry to track the development of hypoxia-induced neovascularization. In addition to developing a preclinical model that phenocopies exudative AMD, our studies revealed that the photoreceptor hypoxic response initiates and drives type 3 neovascularization, mainly in the outer retina. Activation of the VHL-HIF1a-VEGF-EPO pathway in the adult retina led to long-term neovascularization, retinal hemorrhages and compromised retinal layers. Our novel preclinical model would accelerate the testing of therapies that use metabolomic approaches to ameliorate AMD.


Asunto(s)
Hipoxia/metabolismo , Hipoxia/patología , Degeneración Macular/metabolismo , Degeneración Macular/patología , Neovascularización Patológica/metabolismo , Neovascularización Patológica/patología , Animales , Eritropoyetina/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Ratones , Factor A de Crecimiento Endotelial Vascular/metabolismo
19.
Hum Mutat ; 40(12): 2377-2392, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31403230

RESUMEN

Small molecule pharmacological inhibition of dominant human genetic disease is a feasible treatment that does not rely on the development of individual, patient-specific gene therapy vectors. However, the consequences of protein inhibition as a clinical therapeutic are not well-studied. In advance of human therapeutic trials for CAPN5 vitreoretinopathy, genetic inactivation can be used to infer the effect of protein inhibition in vivo. We created a photoreceptor-specific knockout (KO) mouse for Capn5 and compared the retinal phenotype to both wild-type and an existing Capn5 KO mouse model. In humans, CAPN5 loss-of-function (LOF) gene variants were ascertained in large exome databases from 60,706 unrelated subjects without severe disease phenotypes. Ocular examination of the retina of Capn5 KO mice by histology and electroretinography showed no significant abnormalities. In humans, there were 22 LOF CAPN5 variants located throughout the gene and in all major protein domains. Structural modeling of coding variants showed these LOF variants were nearby known disease-causing variants within the proteolytic core and in regions of high homology between human CAPN5 and 150 homologs, yet the LOF of CAPN5 was tolerated as opposed to gain-of-function disease-causing variants. These results indicate that localized inhibition of CAPN5 is a viable strategy for hyperactivating disease alleles.


Asunto(s)
Calpaína/genética , Enfermedades de la Coroides/genética , Enfermedades Hereditarias del Ojo/genética , Mutación , Degeneración Retiniana/genética , Tamoxifeno/farmacología , Animales , Calpaína/química , Calpaína/metabolismo , Modelos Animales de Enfermedad , Femenino , Técnicas de Inactivación de Genes , Silenciador del Gen , Humanos , Masculino , Ratones , Modelos Moleculares , Células Fotorreceptoras de Vertebrados/metabolismo
20.
Cell Mol Life Sci ; 76(18): 3657-3665, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30976840

RESUMEN

D190N, a missense mutation in rhodopsin, causes photoreceptor degeneration in patients with autosomal dominant retinitis pigmentosa (adRP). Two competing hypotheses have been developed to explain why D190N rod photoreceptors degenerate: (a) defective rhodopsin trafficking prevents proteins from correctly exiting the endoplasmic reticulum, leading to their accumulation, with deleterious effects or (b) elevated mutant rhodopsin expression and unabated signaling causes excitotoxicity. A knock-in D190N mouse model was engineered to delineate the mechanism of pathogenesis. Wild type (wt) and mutant rhodopsin appeared correctly localized in rod outer segments of D190N heterozygotes. Moreover, the rhodopsin glycosylation state in the mutants appeared similar to that in wt mice. Thus, it seems plausible that the injurious effect of the heterozygous mutation is not related to mistrafficking of the protein, but rather from constitutive rhodopsin activity and a greater propensity for chromophore isomerization even in the absence of light.


Asunto(s)
Células Fotorreceptoras Retinianas Bastones/metabolismo , Retinitis Pigmentosa/patología , Rodopsina/genética , Secuencia de Aminoácidos , Animales , Modelos Animales de Enfermedad , Electrorretinografía , Técnicas de Sustitución del Gen , Glicosilación , Ratones , Ratones Endogámicos C57BL , Mutación Missense , Estructura Terciaria de Proteína , Retina/metabolismo , Retina/patología , Retinitis Pigmentosa/metabolismo , Rodopsina/química , Rodopsina/metabolismo , Alineación de Secuencia
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