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1.
Arq Bras Oftalmol ; 87(2): e20220237, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38451679

RESUMEN

A 71-year-old woman presented a non-arteritic anterior ischemic optic neuropathy in an optic nerve with previously registered superonasal peripapillary myelinated nerve fibers. Her past medical history was significant for controlled systemic hypertension, hyperlipidemia, and diabetes mellitus. The physiologic cup was absent in both optic discs. Non-arteritic anterior ischemic optic neuropathy mainly affected the temporal and inferior sectors of the peripapillary retinal nerve fiber layer, as could be demonstrated by retinal nerve fiber layer optical coherence tomography and optic disc optical coherence tomography angiography. Unlike other published reports, just a slight regression of the myelinated nerve fibers was observed after 1 year of follow-up. This occurred because ischemia mainly affected the temporal and inferior peripapillary sectors, whereas myelinated nerve fibers were superonasal to the optic disc.


Asunto(s)
Hipertensión , Disco Óptico , Neuropatía Óptica Isquémica , Humanos , Femenino , Anciano , Fibras Nerviosas Mielínicas , Nervio Óptico/diagnóstico por imagen
2.
Eur J Ophthalmol ; 34(3): NP1-NP4, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38403966

RESUMEN

INTRODUCTION: Congenital Central Hypoventilation Syndrome (CCHS) is a rare disease due to a severely impaired central control of breathing and dysfunction of the autonomic nervous system. Ophthalmologic abnormalities are common in patients with CCHS and include horizontal strabismus, pupil and iris abnormalities and ptosis. We report a unique case of CCHS in association with monocular elevation deficit (MED) in a boy diagnosed with CCHS at birth. CASE DESCRIPTION: We report a case of a boy with a confirmed diagnosis of CCHS (complete sequencing of the paired-like homeobox 2b (PHOX2B) gene) after presenting little respiratory effort and cyanosis at birth. The ophthalmological examination shows an impaired elevation of the left eye, both in adduction and abduction, associated with mild and variable left ptosis. His mother has observed that the left eyelid elevates when the child feeds. A deviation in the primary gaze position or a chin-up position are not present. The funduscopic examination is normal. Given that deviation is limited to upgaze, the ptosis is mild and the patient's age, observation is decided. CONCLUSIONS: Ophthalmologic abnormalities are common in patients with CCHS and include horizontal strabismus, pupil and iris abnormalities and ptosis. To the best of our knowledge, this is the first report of MED in association with CCHS. Further studies are needed to determine if an association between MED and CCHS exists or is just a casual finding in this case.


Asunto(s)
Blefaroptosis , Hipoventilación , Hipoventilación/congénito , Apnea Central del Sueño , Humanos , Masculino , Hipoventilación/diagnóstico , Hipoventilación/genética , Hipoventilación/fisiopatología , Blefaroptosis/diagnóstico , Blefaroptosis/congénito , Blefaroptosis/fisiopatología , Apnea Central del Sueño/diagnóstico , Apnea Central del Sueño/fisiopatología , Apnea Central del Sueño/genética , Proteínas de Homeodominio/genética , Recién Nacido , Factores de Transcripción/genética , Estrabismo/diagnóstico , Estrabismo/fisiopatología
3.
Arq. bras. oftalmol ; 87(2): e2022, 2024. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1533788

RESUMEN

ABSTRACT A 71-year-old woman presented a non-arteritic anterior ischemic optic neuropathy in an optic nerve with previously registered superonasal peripapillary myelinated nerve fibers. Her past medical history was significant for controlled systemic hypertension, hyperlipidemia, and diabetes mellitus. The physiologic cup was absent in both optic discs. Non-arteritic anterior ischemic optic neuropathy mainly affected the temporal and inferior sectors of the peripapillary retinal nerve fiber layer, as could be demonstrated by retinal nerve fiber layer optical coherence tomography and optic disc optical coherence tomography angiography. Unlike other published reports, just a slight regression of the myelinated nerve fibers was observed after 1 year of follow-up. This occurred because ischemia mainly affected the temporal and inferior peripapillary sectors, whereas myelinated nerve fibers were superonasal to the optic disc.


RESUMO Uma mulher de 71 anos de idade apresentou neuropatia óptica isquêmica anterior não arterítica no nervo óptico com fibras nervosas peripapilares mielinizadas previamente registradas. Seu histórico médico foi significativo para hipertensão arterial sistêmica controlada, hiperlipidemia e diabetes mellitus. Em ambos os discos ópticos, a tacícula fisiológica esteve ausente. A neuropatia óptica isquêmica anterior não arterítica afetou principalmente os setores temporal e inferior da camada de fibras nervosas da retina peripapilar, como demonstrado pela tomografia de coerência óptica da camada de fibras nervosas da retina e pela angiotomografia de coerência óptica do disco óptico. Ao contrário de outros relatórios publicados, apenas uma ligeira regressão das fibras nervosas mielinizadas foi observada após um ano de acompanhamento. Isto pode ser explicado pelo fato da isquemia ter afetado principalmente os setores temporal e inferior peripapilares, enquanto as fibras nervosas de mielina eram nasal superior ao disco óptico.

4.
Biomimetics (Basel) ; 8(2)2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37366814

RESUMEN

Automation of wrist rotations in upper limb prostheses allows simplification of the human-machine interface, reducing the user's mental load and avoiding compensatory movements. This study explored the possibility of predicting wrist rotations in pick-and-place tasks based on kinematic information from the other arm joints. To do this, the position and orientation of the hand, forearm, arm, and back were recorded from five subjects during transport of a cylindrical and a spherical object between four different locations on a vertical shelf. The rotation angles in the arm joints were obtained from the records and used to train feed-forward neural networks (FFNNs) and time-delay neural networks (TDNNs) in order to predict wrist rotations (flexion/extension, abduction/adduction, and pronation/supination) based on the angles at the elbow and shoulder. Correlation coefficients between actual and predicted angles of 0.88 for the FFNN and 0.94 for the TDNN were obtained. These correlations improved when object information was added to the network or when it was trained separately for each object (0.94 for the FFNN, 0.96 for the TDNN). Similarly, it improved when the network was trained specifically for each subject. These results suggest that it would be feasible to reduce compensatory movements in prosthetic hands for specific tasks by using motorized wrists and automating their rotation based on kinematic information obtained with sensors appropriately positioned in the prosthesis and the subject's body.

5.
Pharmaceutics ; 15(3)2023 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-36986778

RESUMEN

Tyrosine kinase inhibitors (TKIs) have been extensively used as a treatment for chronic myeloid leukemia (CML). Dasatinib is a broad-spectrum TKI with off-target effects that give it an immunomodulatory capacity resulting in increased innate immune responses against cancerous cells and viral infected cells. Several studies reported that dasatinib expanded memory-like natural killer (NK) cells and γδ T cells that have been related with increased control of CML after treatment withdrawal. In the HIV infection setting, these innate cells are associated with virus control and protection, suggesting that dasatinib could have a potential role in improving both the CML and HIV outcomes. Moreover, dasatinib could also directly induce apoptosis of senescence cells, being a new potential senolytic drug. Here, we review in depth the current knowledge of virological and immunogenetic factors associated with the development of powerful cytotoxic responses associated with this drug. Besides, we will discuss the potential therapeutic role against CML, HIV infection and aging.

6.
Int Ophthalmol ; 43(3): 771-777, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36040549

RESUMEN

PURPOSE: To describe the epidemiology and clinical characteristics of psoriatic arthritis (PsA) related uveitis in Madrid, Spain. METHODS: A case series nested in a retrospective single-center cohort of 494 patients with PsA was performed. Patients older than 18 years old whit a clinical diagnosis PsA-related uveitis who attended the Ramon y Cajal University Hospital in Madrid, Spain, between 1st January 2017 and 31st December 2019 were included in the study. Epidemiological and clinical data were retrieved from the electronic medical records. RESULTS: Thirteen cases of psoriatic arthritis-related uveitis (6 men and 7 women) were included. PsA-related uveitis showed an incidence of 0.05 cases per 100,000 persons/year (CI95 0.00-0.35), and a prevalence of 2.19 cases per 100,000 persons (CI95 1.24-3.79). The prevalence of active uveitis in the cohort of PsA patients was 2.6%. The first episode of uveitis (mean age of 48.15 ± 15.41 years) was anterior and unilateral in 92.31% of the cases. Most of the patients had a recurrent course (69.2%) with 0.92 flare-ups per patient/year (CI95 0.85-0.96). The uveitis preceded the diagnosis of psoriatic arthritis in 62.5% of the patients. In patients with PsA-related uveitis, HLA-B27 was present in 23.1%, HLA-Cw6 in 7.7%. CONCLUSIONS: Uveitis is a PsA manifestation that affects roughly 1 in 37 PsA patients, and that may precede the articular symptoms. It generally presents as a unilateral acute anterior uveitis and has a recurrent course. The most frequent observed complications are elevated intraocular pressure and cataracts.


Asunto(s)
Artritis Psoriásica , Uveítis Anterior , Uveítis , Masculino , Humanos , Femenino , Adulto , Persona de Mediana Edad , Adolescente , Artritis Psoriásica/complicaciones , Artritis Psoriásica/diagnóstico , Artritis Psoriásica/epidemiología , Estudios Retrospectivos , España/epidemiología , Uveítis/diagnóstico , Uveítis/epidemiología , Uveítis/etiología , Uveítis Anterior/diagnóstico
7.
eNeuro ; 9(6)2022.
Artículo en Inglés | MEDLINE | ID: mdl-36446569

RESUMEN

Mice are opportunistic omnivores that readily learn to hunt and eat insects such as crickets. The details of how mice learn these behaviors and how these behaviors may differ in strains with altered neuroplasticity are unclear. We quantified the behavior of juvenile wild-type (WT) and Shank3 knock-out (KO) mice as they learned to hunt crickets during the critical period for ocular dominance plasticity. This stage involves heightened cortical plasticity including homeostatic synaptic scaling, which requires Shank3, a glutamatergic synaptic protein that, when mutated, produces Phelan-McDermid syndrome and is often comorbid with autism spectrum disorder (ASD). Both strains showed interest in examining live and dead crickets and learned to hunt. Shank3 knock-out mice took longer to become proficient, and, after 5 d, did not achieve the efficiency of wild-type mice in either time-to-capture or distance-to-capture. Shank3 knock-out mice also exhibited different characteristics when pursuing crickets that could not be explained by a simple motor deficit. Although both genotypes moved at the same average speed when approaching a cricket, Shank3 KO mice paused more often, did not begin final accelerations toward crickets as early, and did not close the distance gap to the cricket as quickly as wild-type mice. These differences in Shank3 KO mice are reminiscent of some behavioral characteristics of individuals with ASD as they perform complex tasks, such as slower action initiation and completion. This paradigm will be useful for exploring the neural circuit mechanisms that underlie these learning and performance differences in monogenic ASD rodent models.


Asunto(s)
Trastorno del Espectro Autista , Animales , Ratones , Trastorno del Espectro Autista/genética , Aprendizaje , Ratones Noqueados , Proteínas de Microfilamentos , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Conducta Predatoria
8.
J Clin Med ; 11(9)2022 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-35566767

RESUMEN

In this article, the effects of cross-section and pitch on the mechanical response of NiTi endodontic files is studied by means of finite element analyses. The study was conducted over a set of eight endodontic rotary files, whose geometry was obtained from combinations of two cross-sections (square and triangular) and four pitches. Each file was subjected to bending and torsional analyses, simulating the testing conditions indicated in the ISO 3630 Standard, in order to assess their stiffness and mechanical strength. The results indicate that endodontic files with a square cross-section have double the stiffness of those with triangular cross-sections, both in terms of bending and torsion. For both loading modes, endodontic files with a triangular cross-section can undergo larger deformations before overload failure than those with a square cross-section: up to 20% more in bending and 40% in torsion. Moreover, under equivalent boundary conditions, endodontic files with triangular cross-sections present a higher fatigue life than those with square cross-sections: up to more than 300% higher for small pitches. The effect of pitch on the stiffness and strength of the file is smaller than that of the cross-section shape, but smaller pitches could be beneficial when using a triangular cross-section, as they increase the bending flexibility, fatigue life, and torsion stiffness. These results suggest a clinical recommendation for the use of files with a triangular-shaped cross-section and a small pitch in order to minimize ledging and maximize fatigue life. Finally, in this study, we reveal the sensitivity of the orientation of files with respect to the bending direction, which must be taken into account when designing, reporting, and interpreting test results under such loading conditions.

9.
eNeuro ; 9(1)2022.
Artículo en Inglés | MEDLINE | ID: mdl-35074827

RESUMEN

Collaboration in neuroscience is impeded by the difficulty of sharing primary data, results, and software across labs. Here, we introduce Neuroscience Data Interface (NDI), a platform-independent standard that allows an analyst to use and create software that functions independently from the format of the raw data or the manner in which the data are organized into files. The interface is rooted in a simple vocabulary that describes common apparatus and storage devices used in neuroscience experiments. Results of analyses, and analyses of analyses, are stored as documents in a scalable, queryable database that stores the relationships and history among the experiment elements and documents. The interface allows the development of an application ecosystem where applications can focus on calculation rather than data format or organization. This tool can be used by individual labs to exchange and analyze data, and it can serve to curate neuroscience data for searchable archives.


Asunto(s)
Almacenamiento y Recuperación de la Información , Neurociencias , Ecosistema , Programas Informáticos , Vocabulario
10.
Br J Ophthalmol ; 106(7): 947-951, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-33597196

RESUMEN

AIMS: To assess visual field (VF) pseudoprogression related to face mask use. METHODS: We reviewed a total of 307 VFs performed with a face mask (FPP2/KN95 or surgical masks) and compared them with prior VFs, performed before the pandemic. VFs with suspected pseudoprogression due to mask artefacts (VF test 1) were repeated with a surgical mask and an adhesive tape on its superior border (VF test 2) to distinguish from true VF loss. Several parameters including reliability indices, test duration, VF index (VFI), mean defect (MD) and pattern deviation probability plots were compared among last pre-COVID VFs, VF tests 1 and VF tests 2, using the Wilcoxon signed-rank test. RESULTS: We identified 18 VFs with suspected progression artefact due to masks (5.8%). In all of them, the median VFI and MD significantly improved after fitting the superior border of the mask, showing no significant differences with pre-COVID tests. The median fixation losses were significantly higher when wearing the unfitted mask (13% vs 6%,p=0.047). The inferior hemifield was the most affected, either as a new scotoma or as an enlargement of a prior defect. CONCLUSION: Unfitted masks can simulate VF progression in around 6% of cases, mainly in the inferior hemifield, and increase significantly the rate of fixation losses. A similar rate of artefacts was observed using FPP2/KN95 or surgical masks. The use of a surgical mask with an adhesive tape covering the superior border may reduce mask-related artefacts, although concomitant progression cannot be ruled out in all cases.


Asunto(s)
COVID-19 , Pruebas del Campo Visual , Artefactos , COVID-19/epidemiología , Humanos , Presión Intraocular , Pandemias , Reproducibilidad de los Resultados
11.
Eur J Ophthalmol ; 32(5): 2886-2892, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34812089

RESUMEN

BACKGROUND: While ptosis is a well-known consequence of glaucoma surgery, some isolated case reports point to the possibility of upper eyelid retraction occurring after glaucoma surgery. This study aims to analyze the occurrence of ptosis and eyelid retraction after glaucoma surgery and to evaluate factors contributing to these palpebral fissure changes. METHODS: Cross-sectional study including 100 eyes of 100 patients that had undergone unilateral glaucoma surgery. Upper eyelid height in the operated eye was measured by digital photography and compared with the fellow, non-operated eye. The main outcome was to determine if ptosis or retraction occurred in the operated eye in comparison with the fellow eye. The secondary outcome was to determine if any variable was associated with ptosis or retraction. A clinically significant difference (either toward ptosis or retraction) was defined as a difference ≥1 mm between both eyes. RESULTS: Of 100 eyes included 81 (81%) showed no change in eyelid height (-0.133 mm ± 0.496), 11 (11%) showed ptosis (-1.348 mm ± 0.387) and 8 eyes (8%) showed retraction (1.705 ± 0.634). A statistically significant relation was found between ptosis and pseudoexfoliation glaucoma (p = 0.003). A trend toward lower postoperative IOP and higher conjunctival blebs was found in eyes with postoperative eyelid retraction. CONCLUSIONS: Eyelid retraction was present in 8% of patients and ptosis in 11%. Patients with eyelid retraction showed around a 3 mmHg lower postoperative IOP than eyes without retraction. The presence of pseudoexfoliation may be a risk factor for this complication. A prospective study with a large number of patients would be required to confirm these results.


Asunto(s)
Blefaroptosis , Enfermedades de los Párpados , Cirugía Filtrante , Glaucoma , Blefaroptosis/cirugía , Estudios Transversales , Enfermedades de los Párpados/etiología , Párpados/cirugía , Cirugía Filtrante/efectos adversos , Glaucoma/complicaciones , Glaucoma/cirugía , Humanos , Músculos Oculomotores/cirugía , Estudios Prospectivos , Estudios Retrospectivos
12.
J Clin Med ; 10(23)2021 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-34884394

RESUMEN

This article describes a numerical procedure for estimating the fatigue life of NiTi endodontic rotary files. An enhanced finite element model reproducing the interaction of the endodontic file rotating inside the root canal was developed, which includes important phenomena that allowed increasing the degree of realism of the simulation. A method based on the critical plane approach was proposed for extracting significant strain results from finite element analysis, which were used in combination with the Coffin-Manson relation to predict the fatigue life of the NiTi rotary files. The proposed procedure is illustrated with several numerical examples in which different combinations of endodontic rotary files and root canal geometries were investigated. By using these analyses, the effect of the radius of curvature and the angle of curvature of the root canal on the fatigue life of the rotary files was analysed. The results confirm the significant influence of the root canal geometry on the fatigue life of the NiTi rotary files and reveal the higher importance of the radius of curvature with respect to the angle of curvature of the root canal.

13.
Biochem Mol Biol Educ ; 49(5): 789-799, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34096689

RESUMEN

DNA structure has been leveraged in a variety of facets that allow scientists to perform a range of assays, including ones for identification of species, establishing evolutionary relationships between taxa, or even identifying individuals. Here, we present a DNA barcoding method as practical, hands-on approach that connects several experimental techniques in one sequence to teach the principles behind DNA isolation, purification, PCR, sequencing, and phylogeny analysis. Our set of exercises is designed for a teaching university laboratory setting. The three laboratory class assignments utilize DNA from a mushroom (can be purchased at a supermarket) and provide a pipeline to guide students through the process of identifying an unknown sample, like in many research laboratories. The third assignment can be used as a stand-alone exercise on phylogeny analysis and can be taught remotely. Students explore the theory behind the standard molecular techniques and apply it in a hands-on setting that involves experimental design, sample preparation, and use of hallmark molecular instruments.


Asunto(s)
Código de Barras del ADN Taxonómico , Laboratorios , Bioquímica , ADN/genética , Humanos , Filogenia , Análisis de Secuencia de ADN
14.
Front Immunol ; 11: 85, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32117246

RESUMEN

Human rhinoviruses (HRV) are the most common cause of viral respiratory tract infections. While normally mild and self-limiting in healthy adults, HRV infections are associated with bronchiolitis in infants, pneumonia in immunocompromised patients, and exacerbations of asthma and COPD. The human cathelicidin LL-37 is a host defense peptide (HDP) with broad immunomodulatory and antimicrobial activities that has direct antiviral effects against HRV. However, LL-37 is known to be susceptible to the enzymatic activity of peptidyl arginine deiminases (PAD), and exposure of the peptide to these enzymes results in the conversion of positively charged arginines to neutral citrullines (citrullination). Here, we demonstrate that citrullination of LL-37 reduced its direct antiviral activity against HRV. Furthermore, while the anti-rhinovirus activity of LL-37 results in dampened epithelial cell inflammatory responses, citrullination of the peptide, and a loss in antiviral activity, ameliorates this effect. This study also demonstrates that HRV infection upregulates PAD2 protein expression, and increases levels of protein citrullination, including histone H3, in human bronchial epithelial cells. Increased PADI gene expression and HDP citrullination during infection may represent a novel viral evasion mechanism, likely applicable to a wide range of pathogens, and should therefore be considered in the design of therapeutic peptide derivatives.


Asunto(s)
Catelicidinas/metabolismo , Citrulinación , Fragmentos de Péptidos/metabolismo , Infecciones por Picornaviridae/metabolismo , Rhinovirus , Bronquios , Catelicidinas/inmunología , Línea Celular , Citocinas/metabolismo , Células Epiteliales , Humanos , Fragmentos de Péptidos/inmunología , Infecciones por Picornaviridae/inmunología , Poli I-C/metabolismo , Arginina Deiminasa Proteína-Tipo 2/metabolismo
15.
Inflamm Bowel Dis ; 25(9): 1481-1496, 2019 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-30889246

RESUMEN

BACKGROUND: Genetic studies have strongly linked autophagy to Crohn's disease (CD), and stimulating autophagy in CD patients may be therapeutically beneficial. The aim of this study was to evaluate the effect of current inflammatory bowel disease (IBD) drugs on autophagy and investigate molecular mechanisms of action and functional outcomes in relation to this cellular process. METHODS: Autophagy marker LC3 was evaluated by confocal fluorescence microscopy and flow cytometry. Drug mechanism of action was investigated by polymerase chain reaction (PCR) array with changes in signaling pathways examined by immunoblot and quantitative reverse transcription PCR (RT-qPCR). Clearance of adherent-invasive Escherichia coli (AIEC) and levels of pro-inflammatory cytokine tumor necrosis factor alpha (TNFα) were evaluated by gentamicin protection assays and RT-qPCR, respectively. The marker LC3 was analyzed in peripheral blood mononuclear cells (PBMCs) from pediatric patients by flow cytometry. RESULTS: Azathioprine induces autophagy via mechanisms involving modulation of mechanistic target of rapamycin (mTORC1) signaling and stimulation of the unfolded protein response (UPR) sensor PERK. Induction of autophagy with azathioprine correlated with the enhanced clearance of AIEC and dampened AIEC-induced increases in TNFα. Azathioprine induced significant increase in autophagosome bound LC3-II in PBMC populations ex vivo, supporting in vitro findings. In patients, the CD-associated ATG16L1 T300A single-nucleotide polymorphism did not attenuate azathioprine induction of autophagy. CONCLUSIONS: Modulation of autophagy via mTORC1 and the UPR may contribute to the therapeutic efficacy of azathioprine in IBD.


Asunto(s)
Autofagia , Azatioprina/farmacología , Escherichia coli/crecimiento & desarrollo , Enfermedades Inflamatorias del Intestino/patología , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Respuesta de Proteína Desplegada/efectos de los fármacos , eIF-2 Quinasa/metabolismo , Adolescente , Estudios de Casos y Controles , Niño , Escherichia coli/efectos de los fármacos , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/metabolismo , Infecciones por Escherichia coli/microbiología , Femenino , Humanos , Inmunosupresores/farmacología , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/metabolismo , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Leucocitos Mononucleares/patología , Masculino , Diana Mecanicista del Complejo 1 de la Rapamicina/genética , eIF-2 Quinasa/genética
16.
PLoS One ; 14(1): e0209665, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30699149

RESUMEN

The cytoskeletal protein vimentin plays a key role in positioning of organelles within the cytosol and has been linked to the regulation of numerous cellular processes including autophagy, however, how vimentin regulates autophagy remains relatively unexplored. Here we report that inhibition of vimentin using the steroidal lactone Withaferin A (WFA) causes vimentin to aggregate, and this is associated with the relocalisation of organelles including autophagosomes and lysosomes from the cytosol to a juxtanuclear location. Vimentin inhibition causes autophagosomes to accumulate, and we demonstrate this results from modulation of mechanistic target of rapamycin (mTORC1) activity, and disruption of autophagosome-lysosome fusion. We suggest that vimentin plays a physiological role in autophagosome and lysosome positioning, thus identifying vimentin as a key factor in the regulation of mTORC1 and autophagy.


Asunto(s)
Orgánulos/fisiología , Vimentina/metabolismo , Vimentina/fisiología , Autofagosomas/metabolismo , Autofagia/fisiología , Línea Celular Tumoral , Citoesqueleto/fisiología , Citosol , Células HEK293 , Humanos , Filamentos Intermedios/metabolismo , Lisosomas/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Fusión de Membrana/fisiología , Transducción de Señal , Witanólidos/farmacología
17.
Minor Planet Bull ; 46(1): 55-58, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32455412

RESUMEN

Photometric observations of the near-Earth asteroid (31345) 1998 PG by Pravec et al. (2000) found a rotation period of 2.51620 h. Also found was a secondary period of 7.0035 h, or the double-period of 14.007 h, possibly indicating an additional body in the system. An extended campaign by the authors in 2018 lead to a similar primary period of 2.5168 h. However, instead of a 7-hour secondary period, one of about 16 hours was found with the lightcurve showing apparent mutual events (occultations and/or eclipses). The data sets from 1998 and 2018 could not be fit to a secondary period near the one found at the opposing apparition. The conclusion is that the asteroid is very likely binary, but - other than the primary rotation period - the system's parameters are ill-defined and only future observations will sufficiently refine them.

18.
Future Virol ; 13(7): 505-518, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30245735

RESUMEN

Human rhinoviruses are the primary etiological agent of the common cold. This infection can be mild and self-limiting in immunocompetent hosts, but can be associated with bronchiolitis in infants, pneumonia in the immunosuppressed and exacerbations of pre-existing pulmonary conditions such as asthma or chronic obstructive pulmonary disease. Many of these conditions can place significant economic costs upon healthcare infrastructure. There is currently no licensed vaccine for rhinovirus, as the large variety of rhinovirus serotypes has posed significant challenges for research. In this review, we discuss current knowledge around antiviral drugs and small molecule inhibitors of rhinovirus infection, as well as antiviral host defense peptides as exciting prospects to approach the development of novel therapeutics which target human rhinovirus.

19.
Peptides ; 95: 76-83, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28764966

RESUMEN

Human rhinoviruses (HRVs) are the most common cause of viral respiratory tract infections, and are associated with significant morbidity and mortality in immunocompromised individuals and patients with pre-existing pulmonary conditions. The therapeutic options available are extremely limited and therefore novel therapeutics for HRV infections are of significant interest. Cathelicidins have been shown to have potent antiviral activity against a range of pathogens and are known to be key immunomodulatory mediators during infection. We therefore assessed the antiviral potential of cathelicidins from humans and other mammalian species against HRV, together with the potential for the human cathelicidin to modulate apoptotic pathways and alter cell viability during HRV infection. We demonstrate that LL-37, the porcine cathelicidin Protegrin-1, and the ovine cathelicidin SMAP-29 display potent antiviral activity towards HRV and that this activity is visible when either the virus is exposed to the peptides prior to cell infection or after cells have been infected. We further demonstrate that, in contrast to established findings with bacterial infection models, LL-37 does not induce apoptosis or necrosis in HRV-infected lung epithelial cells at physiological or superphysiological concentrations, but does reduce the metabolic activity of infected cells compared to uninfected cells treated with similar peptide concentrations. Collectively, the findings from this study demonstrate that the mechanism of action of cathelicidins against rhinovirus is by directly affecting the virus and we propose that the delivery of exogenous cathelicidins, or novel synthetic analogues, represent an exciting and novel therapeutic strategy for rhinovirus infection.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/farmacología , Catelicidinas/farmacología , Infecciones del Sistema Respiratorio/tratamiento farmacológico , Rhinovirus/efectos de los fármacos , Animales , Péptidos Catiónicos Antimicrobianos/uso terapéutico , Antivirales/farmacología , Antivirales/uso terapéutico , Proteínas Sanguíneas/farmacología , Proteínas Sanguíneas/uso terapéutico , Catelicidinas/genética , Catelicidinas/uso terapéutico , Células Epiteliales/efectos de los fármacos , Células Epiteliales/virología , Humanos , Infecciones del Sistema Respiratorio/genética , Infecciones del Sistema Respiratorio/virología , Rhinovirus/patogenicidad , Ovinos , Porcinos
20.
J Leukoc Biol ; 99(2): 349-59, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26310829

RESUMEN

Regulatory T cells have an important role in immune suppression during HIV-1 infection. As regulatory T cells produce the immunomodulatory molecule adenosine, our aim here was to assess the potential of adenosine removal to revert the suppression of anti-HIV responses exerted by regulatory T cells. The experimental setup consisted of ex vivo cocultures of T and dendritic cells, to which adenosine deaminase, an enzyme that hydrolyzes adenosine, was added. In cells from healthy individuals, adenosine hydrolysis decreased CD4(+)CD25(hi) regulatory T cells. Addition of 5'-N-ethylcarboxamidoadenosine, an adenosine receptor agonist, significantly decreased CD4(+)CD25(lo) cells, confirming a modulatory role of adenosine acting via adenosine receptors. In autologous cocultures of T cells with HIV-1-pulsed dendritic cells, addition of adenosine deaminase led to a significant decrease of HIV-1-induced CD4(+)CD25(hi) forkhead box p3(+) cells and to a significant enhancement of the HIV-1-specific CD4(+) responder T cells. An increase in the effector response was confirmed by the enhanced production of CD4(+) and CD8(+) CD25(-)CD45RO(+) memory cell generation and secretion of Th1 cytokines, including IFN-γ and IL-15 and chemokines MIP-1α/CCL3, MIP-1ß/CCL4, and RANTES/CCL5. These ex vivo results show, in a physiologically relevant model, that adenosine deaminase is able to enhance HIV-1 effector responses markedly. The possibility to revert regulatory T cell-mediated inhibition of immune responses by use of adenosine deaminase, an enzyme that hydrolyzes adenosine, merits attention for restoring T lymphocyte function in HIV-1 infection.


Asunto(s)
Adenosina Desaminasa/farmacología , Células Dendríticas/efectos de los fármacos , Infecciones por VIH/inmunología , VIH-1 , Subgrupos de Linfocitos T/inmunología , Linfocitos T Reguladores/efectos de los fármacos , Adenosina/metabolismo , Adenosina-5'-(N-etilcarboxamida)/farmacología , Antígenos CD/análisis , Antígenos de Diferenciación de Linfocitos T/análisis , Linfocitos T CD8-positivos/inmunología , Quimiocinas/metabolismo , Técnicas de Cocultivo , Femenino , Factores de Transcripción Forkhead/análisis , Infecciones por VIH/patología , Humanos , Memoria Inmunológica , Activación de Linfocitos/efectos de los fármacos , Linfocinas/metabolismo , Masculino , Agonistas del Receptor Purinérgico P1/farmacología , Subgrupos de Linfocitos T/metabolismo , Linfocitos T Reguladores/química , Linfocitos T Reguladores/metabolismo , Células TH1/metabolismo
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