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1.
Cell ; 187(2): 276-293.e23, 2024 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-38171360

RESUMEN

During development, morphogens pattern tissues by instructing cell fate across long distances. Directly visualizing morphogen transport in situ has been inaccessible, so the molecular mechanisms ensuring successful morphogen delivery remain unclear. To tackle this longstanding problem, we developed a mouse model for compromised sonic hedgehog (SHH) morphogen delivery and discovered that endocytic recycling promotes SHH loading into signaling filopodia called cytonemes. We optimized methods to preserve in vivo cytonemes for advanced microscopy and show endogenous SHH localized to cytonemes in developing mouse neural tubes. Depletion of SHH from neural tube cytonemes alters neuronal cell fates and compromises neurodevelopment. Mutation of the filopodial motor myosin 10 (MYO10) reduces cytoneme length and density, which corrupts neuronal signaling activity of both SHH and WNT. Combined, these results demonstrate that cytoneme-based signal transport provides essential contributions to morphogen dispersion during mammalian tissue development and suggest MYO10 is a key regulator of cytoneme function.


Asunto(s)
Estructuras de la Membrana Celular , Miosinas , Tubo Neural , Transducción de Señal , Animales , Ratones , Transporte Biológico , Estructuras de la Membrana Celular/metabolismo , Proteínas Hedgehog/metabolismo , Miosinas/metabolismo , Seudópodos/metabolismo , Tubo Neural/citología , Tubo Neural/metabolismo
2.
J Am Acad Dermatol ; 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38556093

RESUMEN

BACKGROUND: Efficacy and/or safety profiles limit topical psoriasis treatments. OBJECTIVE: Evaluate long-term effects of once-daily roflumilast cream 0.3% in patients with psoriasis. METHODS: In this open-label phase 2 trial, adult patients (N = 332) with psoriasis who completed the phase 2b parent trial or were newly enrolled applied roflumilast once-daily for 52 weeks. Safety and effectiveness were assessed. RESULTS: Overall, 244 patients (73.5%) completed the trial; 13 patients (3.9%) discontinued due to adverse events (AEs) and 3 (0.9%) due to lack of efficacy. Twelve patients (3.6%) reported treatment-related AEs; none were serious. ≥97% of patients had no irritation. No tachyphylaxis was observed with 44.8% of the patients achieving Investigator Global Assessment (IGA) Clear or Almost Clear at Week 52. LIMITATIONS: Intertriginous-IGA and Psoriasis Area and Severity Index (PASI) were not evaluated in all patients. CONCLUSIONS: In this long-term trial, once-daily roflumilast cream was well-tolerated and efficacious up to 64 weeks in patients in the earlier trial, suggesting it is suitable for chronic treatment, including the face and intertriginous areas.

3.
J Public Health (Oxf) ; 45(2): e215-e224, 2023 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-36309802

RESUMEN

In 2021, during a drug-related death crisis in the UK, the Government published its ten-year drugs strategy. This article, written in collaboration with the Faculty of Public Health and the Association of Directors of Public Health, assesses whether this Strategy is evidence-based and consistent with international calls to promote public health approaches to drugs, which put 'people, health and human rights at the centre'. Elements of the Strategy are welcome, including the promise of significant funding for drug treatment services, the effects of which will depend on how it is utilized by services and local commissioners and whether it is sustained. However, unevidenced and harmful measures to deter drug use by means of punishment continue to be promoted, which will have deleterious impacts on people who use drugs. An effective public health approach to drugs should tackle population-level risk factors, which may predispose to harmful patterns of drug use, including adverse childhood experiences and socioeconomic deprivation, and institute evidence-based measures to mitigate drug-related harm. This would likely be more effective, and just, than the continuation of policies rooted in enforcement. A more dramatic re-orientation of UK drug policy than that offered by the Strategy is overdue.


Asunto(s)
Política Pública , Trastornos Relacionados con Sustancias , Humanos , Salud Pública , Trastornos Relacionados con Sustancias/prevención & control , Gobierno , Reino Unido
4.
Australas Psychiatry ; 31(6): 782-785, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37625817

RESUMEN

OBJECTIVES: Mental health (MH) patients seen in the emergency department (ED) setting are often viewed in isolation, outside of the context of their loved ones, the next of kin (NOK). This is especially problematic when a patient is detained under the mental health act. This project aimed to improve this engagement. METHODS: A sense of urgency was created from a guiding coalition of the local MH and ED executive of a rural hospital. The vision was communicated to the team for action. This was then institutionally incorporated as best practice during a 3 month trial. RESULTS: NOK were engaged more frequently as a result of this quality improvement strategy, rising to 90.8% (2021) from 63.2% (2020) compared to the previous year χ2 (1, N=166) =18.75, p = .000015. Admissions for all MH patients from the emergency department fell to 28.3% (2021) from 39% (2020) χ2 (1, N=652) =8.32, p = .0039. CONCLUSIONS: Working with NOK is a best practice strategy that was embraced by clinicians when highlighted. This resulted in less restrictive practice and more community treatment. Creating a frame for the patient that is standardised, provides containment and co-designs future health care is beneficial.


Asunto(s)
Enfermos Mentales , Alta del Paciente , Humanos , Salud Mental , Mejoramiento de la Calidad , Hospitalización , Servicio de Urgencia en Hospital
5.
Conserv Biol ; 36(1): e13868, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34856010

RESUMEN

Biodiversity conservation decisions are difficult, especially when they involve differing values, complex multidimensional objectives, scarce resources, urgency, and considerable uncertainty. Decision science embodies a theory about how to make difficult decisions and an extensive array of frameworks and tools that make that theory practical. We sought to improve conceptual clarity and practical application of decision science to help decision makers apply decision science to conservation problems. We addressed barriers to the uptake of decision science, including a lack of training and awareness of decision science; confusion over common terminology and which tools and frameworks to apply; and the mistaken impression that applying decision science must be time consuming, expensive, and complex. To aid in navigating the extensive and disparate decision science literature, we clarify meaning of common terms: decision science, decision theory, decision analysis, structured decision-making, and decision-support tools. Applying decision science does not have to be complex or time consuming; rather, it begins with knowing how to think through the components of a decision utilizing decision analysis (i.e., define the problem, elicit objectives, develop alternatives, estimate consequences, and perform trade-offs). This is best achieved by applying a rapid-prototyping approach. At each step, decision-support tools can provide additional insight and clarity, whereas decision-support frameworks (e.g., priority threat management and systematic conservation planning) can aid navigation of multiple steps of a decision analysis for particular contexts. We summarize key decision-support frameworks and tools and describe to which step of a decision analysis, and to which contexts, each is most useful to apply. Our introduction to decision science will aid in contextualizing current approaches and new developments, and help decision makers begin to apply decision science to conservation problems.


Las decisiones sobre la conservación de la biodiversidad son difíciles de tomar, especialmente cuando involucran diferentes valores, objetivos multidimensionales complejos, recursos limitados, urgencia y una incertidumbre considerable. Las ciencias de la decisión incorporan una teoría sobre cómo tomar decisiones difíciles y una variedad extensa de marcos de trabajo y herramientas que transforman esa teoría en práctica. Buscamos mejorar la claridad conceptual y la aplicación práctica de las ciencias de la decisión para ayudar al órgano decisorio a aplicar estas ciencias a los problemas de conservación. Nos enfocamos en las barreras para la aceptación de las ciencias de la decisión, incluyendo la falta de capacitación y de conciencia por estas ciencias; la confusión por la terminología común y cuáles herramientas y marcos de trabajo aplicar; y la impresión errónea de que la aplicación de estas ciencias consume tiempo y debe ser costosa y compleja. Para asistir en la navegación de la literatura extensa y dispar de las ciencias de la decisión, aclaramos el significado de varios términos comunes: ciencias de la decisión, teoría de la decisión, análisis de decisiones, toma estructurada de decisiones y herramientas de apoyo para las decisiones. La aplicación de las ciencias de la decisión no tiene que ser compleja ni debe llevar mucho tiempo; de hecho, todo comienza con saber cómo pensar detenidamente en los componentes de una decisión mediante el análisis de decisiones (es decir, definir el problema, producir objetivos, desarrollar alternativas, estimar consecuencias y realizar compensaciones). Lo anterior se logra de mejor manera mediante la aplicación de una estrategia prototipos rápidos. En cada paso, las herramientas de apoyo para las decisiones pueden proporcionar visión y claridad adicionales, mientras que los marcos de apoyo para las decisiones (p.ej.: gestión de amenazas prioritarias y planeación sistemática de la conservación) pueden asistir en la navegación de los diferentes pasos de un análisis de decisiones para contextos particulares. Resumimos los marcos de trabajo y las herramientas más importantes de apoyo para las decisiones y describimos el paso, y el contexto, del análisis de decisiones para el que es más útil aplicarlos. Nuestra introducción a las ciencias de la decisión apoyará en la contextualización de las estrategias actuales y los nuevos desarrollos, y ayudarán al órgano decisorio a comenzar a aplicar estas ciencias en los problemas de conservación.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Conservación de los Recursos Naturales/métodos , Toma de Decisiones , Incertidumbre
6.
Chemistry ; 26(60): 13606-13610, 2020 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-32452589

RESUMEN

The grafting of imidazole species onto coordinatively unsaturated sites within metal-organic framework MIL-101(Cr) enables enhanced CO2 capture in close proximity to catalytic sites. The subsequent combination of CO2 and epoxide binding sites, as shown through theoretical findings, significantly improves the rate of cyclic carbonate formation, producing a highly active CO2 utilization catalyst. An array of spectroscopic investigations, in combination with theoretical calculations reveal the nature of the active sites and associated catalytic mechanism which validates the careful design of the hybrid MIL-101(Cr).

7.
Am J Kidney Dis ; 73(3): 421-424, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30201548

RESUMEN

Gitelman syndrome is caused by inactivating mutations of the gene that encodes the renal sodium/chloride cotransporter (NCC; encoded by SLC12A3), resulting in hypokalemia, hypomagnesemia, hypocalciuria, and metabolic alkalosis. Renal salt wasting commonly provokes mild hypotension. The paucity of previous kidney transplants from donors with known tubulopathies suggests that such conditions may be considered contraindications to donation. A 76-year-old man received a live unrelated kidney transplant from a donor with known Gitelman syndrome secondary to a pathogenic mutation of SLC12A3. Immediate graft function preceded the emergence of the Gitelman syndrome biochemical phenotype and blood pressure subsequently improved. The recipient developed unexpected hyponatremia. Potential causes are discussed, including the possibility that it paralleled the physiologic changes seen in the high-volume state of thiazide-induced hyponatremia. Transplanted kidneys are subject to nephrotoxicity from the use of calcineurin inhibitors. Acquired Gitelman syndrome may confer a potential long-term advantage to the recipient through both improved blood pressure control and protection against the calcineurin inhibitor-induced side-effect profile caused by NCC overactivation. Both the donor and recipient remain well. In conclusion, Gitelman syndrome need not preclude kidney donation and transference of the phenotype may have benefits for the recipient.


Asunto(s)
Síndrome de Gitelman , Hipertensión/cirugía , Trasplante de Riñón , Anciano , Selección de Donante , Humanos , Masculino
8.
Circ Res ; 120(2): 312-323, 2017 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-27799253

RESUMEN

RATIONALE: Sympathetic nervous system control of inflammation plays a central role in hypertension. The gut receives significant sympathetic innervation, is densely populated with a diverse microbial ecosystem, and contains immune cells that greatly impact overall inflammatory homeostasis. Despite this uniqueness, little is known about the involvement of the gut in hypertension. OBJECTIVE: Test the hypothesis that increased sympathetic drive to the gut is associated with increased gut wall permeability, increased inflammatory status, and microbial dysbiosis and that these gut pathological changes are linked to hypertension. METHODS AND RESULTS: Gut epithelial integrity and wall pathology were examined in spontaneously hypertensive rat and chronic angiotensin II infusion rat models. The increase in blood pressure in spontaneously hypertensive rat was associated with gut pathology that included increased intestinal permeability and decreased tight junction proteins. These changes in gut pathology in hypertension were associated with alterations in microbial communities relevant in blood pressure control. We also observed enhanced gut-neuronal communication in hypertension originating from paraventricular nucleus of the hypothalamus and presenting as increased sympathetic drive to the gut. Finally, angiotensin-converting enzyme inhibition (captopril) normalized blood pressure and was associated with reversal of gut pathology. CONCLUSIONS: A dysfunctional sympathetic-gut communication is associated with gut pathology, dysbiosis, and inflammation and plays a key role in hypertension. Thus, targeting of gut microbiota by innovative probiotics, antibiotics, and fecal transplant, in combination with the current pharmacotherapy, may be a novel strategy for hypertension treatment.


Asunto(s)
Microbioma Gastrointestinal/fisiología , Hipertensión/metabolismo , Hipertensión/fisiopatología , Mucosa Intestinal/metabolismo , Mucosa Intestinal/fisiopatología , Angiotensina II/toxicidad , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Animales , Microbioma Gastrointestinal/efectos de los fármacos , Hipertensión/tratamiento farmacológico , Mucosa Intestinal/efectos de los fármacos , Masculino , Permeabilidad/efectos de los fármacos , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY , Ratas Sprague-Dawley , Ratas Wistar
10.
PLoS Genet ; 11(8): e1005473, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26291458

RESUMEN

The G protein-coupled receptor (GPCR) Smoothened (Smo) is the requisite signal transducer of the evolutionarily conserved Hedgehog (Hh) pathway. Although aspects of Smo signaling are conserved from Drosophila to vertebrates, significant differences have evolved. These include changes in its active sub-cellular localization, and the ability of vertebrate Smo to induce distinct G protein-dependent and independent signals in response to ligand. Whereas the canonical Smo signal to Gli transcriptional effectors occurs in a G protein-independent manner, its non-canonical signal employs Gαi. Whether vertebrate Smo can selectively bias its signal between these routes is not yet known. N-linked glycosylation is a post-translational modification that can influence GPCR trafficking, ligand responsiveness and signal output. Smo proteins in Drosophila and vertebrate systems harbor N-linked glycans, but their role in Smo signaling has not been established. Herein, we present a comprehensive analysis of Drosophila and murine Smo glycosylation that supports a functional divergence in the contribution of N-linked glycans to signaling. Of the seven predicted glycan acceptor sites in Drosophila Smo, one is essential. Loss of N-glycosylation at this site disrupted Smo trafficking and attenuated its signaling capability. In stark contrast, we found that all four predicted N-glycosylation sites on murine Smo were dispensable for proper trafficking, agonist binding and canonical signal induction. However, the under-glycosylated protein was compromised in its ability to induce a non-canonical signal through Gαi, providing for the first time evidence that Smo can bias its signal and that a post-translational modification can impact this process. As such, we postulate a profound shift in N-glycan function from affecting Smo ER exit in flies to influencing its signal output in mice.


Asunto(s)
Proteínas de Drosophila/metabolismo , Procesamiento Proteico-Postraduccional , Receptores Acoplados a Proteínas G/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia Conservada , Drosophila melanogaster , Glicosilación , Células HEK293 , Humanos , Ratones , Datos de Secuencia Molecular , Células 3T3 NIH , Unión Proteica , Transporte de Proteínas , Transducción de Señal , Receptor Smoothened , Especificidad de la Especie
12.
BMC Vet Res ; 13(1): 37, 2017 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-28143485

RESUMEN

BACKGROUND: Mokola virus (MOKV) is a rabies-related lyssavirus and appears to be exclusive to the African continent. Only 24 cases of MOKV, which includes two human cases, have been reported since its identification in 1968. MOKV has an unknown reservoir host and current commercial vaccines do not confer protection against MOKV. RESULTS: We describe three new isolations of MOKV from domestic cats in South Africa. Two cases were retrospectively identified from 2012 and an additional one in 2014. CONCLUSIONS: These cases emphasize the generally poor surveillance for rabies-related lyssaviruses and our inadequate comprehension of the epidemiology and ecology of Mokola lyssavirus per se.


Asunto(s)
Enfermedades de los Gatos/virología , Lyssavirus/aislamiento & purificación , Infecciones por Rhabdoviridae/veterinaria , Animales , Gatos , Femenino , Lyssavirus/genética , Masculino , Estudios Retrospectivos , Infecciones por Rhabdoviridae/virología , Sudáfrica
13.
Arch Gynecol Obstet ; 295(1): 67-73, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27677283

RESUMEN

PURPOSE: To explore whether the characteristics of vacuum delivery are associated with the occurrence of head injury and neonatal complications. METHODS: Retrospectively cohort study of vacuum-assisted attempted vaginal deliveries of singletons. We studied the association of total duration of vacuum application and number of pulls and cup dislodgement with (1) primary outcome: the occurrence of major (subgaleal hemorrhage, skull fracture, and intracranial hemorrhage) or minor (cephalohematoma, scalp laceration more extensive than simple abrasions) neonatal head injuries and (2) secondary outcome: the occurrence of neonatal complications, including 5-min Apgar score <7, umbilical artery pH < 7.10, shoulder dystocia, or need for neonatal intensive care unit admission. Logistic regression analysis was used to control for confounders. RESULTS: Vacuum-assisted delivery was attempted in 555 women. It was successful in 515 cases, and it failed in 40 (7.2 %). Head injury occurred in 32 (6.2 %) of vaginally delivered neonates, and it was related to duration of vacuum application (P = 0.004) and birth weight (P = 0.048). However, the associations lost a statistical significance at the multivariate analysis. Neonatal complications occurred in 25 cases (5 %), and they were associated with meconium-stained amniotic fluid (P < 0.001) and duration of vacuum application (P = 0.03) at the multivariate analysis. However, most of the complications were actually associated with the need for vacuum delivery rather than the procedure itself. CONCLUSION: Neonatal head injury after vacuum application is not independently related to total duration of vacuum application, number of pulls, or cup dislodgements.


Asunto(s)
Traumatismos del Nacimiento/etiología , Traumatismos Craneocerebrales/etiología , Enfermedades Fetales/etiología , Extracción Obstétrica por Aspiración/efectos adversos , Extracción Obstétrica por Aspiración/métodos , Adulto , Estudios de Cohortes , Femenino , Humanos , Recién Nacido , Embarazo , Estudios Retrospectivos
14.
Mo Med ; 114(2): 116-119, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-30228557

RESUMEN

Affecting over 100,000 older Missourians, cognitive impairment is of concern for all health care providers. With no available pharmacologic treatments to eradicate/diminish symptoms, professionals and families need non-pharmacologic behavioral interventions to enhance individuals' quality-of-life and decrease the number and intensity of dementia-related behavioral symptoms. This paper provides an overview of available evidence-based non-pharmacologic interventions and strategies that can be delivered in both the community and facility setting, including reminiscence, validation, and cognitive stimulation therapies.

15.
J Gerontol Soc Work ; 60(4): 300-312, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28409672

RESUMEN

Affecting nearly 5.4 million older adults in the United States and 35.6 million individuals worldwide, dementia is one of the greatest public health crises of our time. As a result, helping professionals, clients, and care partners seek effective and affordable treatment. Developed in the United Kingdom by Spector and colleagues, Cognitive Stimulation Therapy (CST) is a non-pharmacologic psychosocial group intervention for persons with dementia. To expand upon and fill the gaps within existing research, the authors developed a descriptive study to assess the impact of CST on cognition, quality of life, and depression, among six CST groups (n = 40). A paired sample t-test was run among pre- and post-test measures. There was a statistically significant difference in Saint Louis University Mental Status Exam (SLUMS) scores after CST (t = 2.80, p = 0.008). There was also a statistically significant difference in Cornell Scale for Depression in Dementia scores (t = -3.36, p = 0.002). There was no statistically significant difference in Quality of Life scores.


Asunto(s)
Terapia Cognitivo-Conductual/instrumentación , Terapia Cognitivo-Conductual/métodos , Demencia/terapia , Anciano , Anciano de 80 o más Años , Depresión/terapia , Femenino , Humanos , Masculino , Pruebas de Estado Mental y Demencia , Persona de Mediana Edad , Psicoterapia de Grupo/instrumentación , Psicoterapia de Grupo/métodos , Reino Unido
16.
J Hand Surg Am ; 41(10): e375-e377, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27469934

RESUMEN

Carpal coalition, the union of 2 or more carpal bones, can be congenital or acquired. Congenital, nonsyndromic carpal coalition usually presents in otherwise healthy individuals. The most common coalition is between the lunate and the triquetrum, followed by the capitate and the hamate. Pancarpal coalition, or coalition of all or most of the bones of the carpus, is an extremely rare finding and usually occurs as part of a syndrome. We present a nonsyndromic case of this rare entity, in a 28-year-old woman of West African descent, with symptoms of left hand and wrist pain. Our literature review revealed only 1 other reported case of isolated, nonsyndromic symptomatic pancarpal coalition.


Asunto(s)
Artralgia/rehabilitación , Huesos del Carpo/anomalías , Anomalías Congénitas/diagnóstico , Articulación de la Muñeca/fisiopatología , Adulto , Artralgia/diagnóstico por imagen , Huesos del Carpo/diagnóstico por imagen , Anomalías Congénitas/rehabilitación , Terapia por Ejercicio/métodos , Femenino , Humanos , Radiografía/métodos , Enfermedades Raras , Recuperación de la Función/fisiología , Medición de Riesgo , Articulación de la Muñeca/diagnóstico por imagen
17.
Development ; 139(3): 612-21, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22223683

RESUMEN

The Hedgehog (Hh) signaling pathway plays an instructional role during development, and is frequently activated in cancer. Ligand-induced pathway activation requires signaling by the transmembrane protein Smoothened (Smo), a member of the G-protein-coupled receptor (GPCR) superfamily. The extracellular (EC) loops of canonical GPCRs harbor cysteine residues that engage in disulfide bonds, affecting active and inactive signaling states through regulating receptor conformation, dimerization and/or ligand binding. Although a functional importance for cysteines localized to the N-terminal extracellular cysteine-rich domain has been described, a functional role for a set of conserved cysteines in the EC loops of Smo has not yet been established. In this study, we mutated each of the conserved EC cysteines, and tested for effects on Hh signal transduction. Cysteine mutagenesis reveals that previously uncharacterized functional roles exist for Smo EC1 and EC2. We provide in vitro and in vivo evidence that EC1 cysteine mutation induces significant Hh-independent Smo signaling, triggering a level of pathway activation similar to that of a maximal Hh response in Drosophila and mammalian systems. Furthermore, we show that a single amino acid change in EC2 attenuates Hh-induced Smo signaling, whereas deletion of the central region of EC2 renders Smo fully active, suggesting that the conformation of EC2 is crucial for regulated Smo activity. Taken together, these findings are consistent with loop cysteines engaging in disulfide bonds that facilitate a Smo conformation that is silent in the absence of Hh, but can transition to a fully active state in response to ligand.


Asunto(s)
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Proteínas Hedgehog/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Secuencia de Aminoácidos , Animales , Cisteína/química , Cisteína/genética , Cisteína/metabolismo , Proteínas de Drosophila/química , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Masculino , Datos de Secuencia Molecular , Mutagénesis , Conformación Proteica , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/genética , Transducción de Señal , Receptor Smoothened , Alas de Animales/metabolismo
18.
J Cell Biol ; 223(9)2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-38856684

RESUMEN

Sonic Hedgehog (SHH) is a driver of embryonic patterning that, when corrupted, triggers developmental disorders and cancers. SHH effector responses are organized through primary cilia (PC) that grow and retract with the cell cycle and in response to extracellular cues. Disruption of PC homeostasis corrupts SHH regulation, placing significant pressure on the pathway to maintain ciliary fitness. Mechanisms by which ciliary robustness is ensured in SHH-stimulated cells are not yet known. Herein, we reveal a crosstalk circuit induced by SHH activation of Phospholipase A2α that drives ciliary E-type prostanoid receptor 4 (EP4) signaling to ensure PC function and stabilize ciliary length. We demonstrate that blockade of SHH-EP4 crosstalk destabilizes PC cyclic AMP (cAMP) equilibrium, slows ciliary transport, reduces ciliary length, and attenuates SHH pathway induction. Accordingly, Ep4-/- mice display shortened neuroepithelial PC and altered SHH-dependent neuronal cell fate specification. Thus, SHH initiates coordination between distinct ciliary receptors to maintain PC function and length homeostasis for robust downstream signaling.


Asunto(s)
Cilios , Proteínas Hedgehog , Prostaglandinas , Transducción de Señal , Animales , Ratones , Cilios/metabolismo , AMP Cíclico/metabolismo , Proteínas Hedgehog/metabolismo , Proteínas Hedgehog/genética , Ratones Noqueados , Prostaglandinas/metabolismo , Subtipo EP4 de Receptores de Prostaglandina E/metabolismo , Subtipo EP4 de Receptores de Prostaglandina E/genética
19.
Mol Vis ; 19: 463-75, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23441119

RESUMEN

PURPOSE: Human eye lenses contain cells that persist from embryonic development. These unique, highly specialized fiber cells located at the core (nucleus) of the lens undergo pseudo-apoptosis to become devoid of cell nuclei and most organelles. Ostensibly lacking in protein transcriptional capabilities, it is currently believed that these nuclear fiber cells owe their extreme longevity to the perseverance of highly stable and densely packed crystallin proteins. Maintaining the structural and functional integrity of lenticular proteins is necessary to sustain cellular transparency and proper vision, yet the means by which the lens actually copes with a lifetime of oxidative stress, seemingly without any capacity for protein turnover and repair, is not completely understood. Although many years of research have been predicated upon the assumption that there is no protein turnover or renewal in nuclear fiber cells, we investigated whether or not different protein fractions possess protein of different ages by using the (14)C bomb pulse. METHODS: Adult human lenses were concentrically dissected by gently removing the cell layers in water or shaving to the nucleus with a curved micrometer-controlled blade. The cells were lysed, and the proteins were separated into water-soluble and water-insoluble fractions. The small molecules were removed using 3 kDa spin filters. The (14)C/C was measured in paired protein fractions by accelerator mass spectrometry, and an average age for the material within the sample was assigned using the (14)C bomb pulse. RESULTS: The water-insoluble fractions possessed (14)C/C ratios consistent with the age of the cells. In all cases, the water-soluble fractions contained carbon that was younger than the paired water-insoluble fraction. CONCLUSIONS: As the first direct evidence of carbon turnover in protein from adult human nuclear fiber cells, this discovery supports the emerging view of the lens nucleus as a dynamic system capable of maintaining homeostasis in part due to intricate protein transport mechanisms and possibly protein repair. This finding implies that the lens plays an active role in the aversion of age-related nuclear (ARN) cataract.


Asunto(s)
Carbono/metabolismo , Cristalinas/metabolismo , Núcleo del Cristalino/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Envejecimiento/metabolismo , Radioisótopos de Carbono/metabolismo , Cristalinas/química , Humanos , Núcleo del Cristalino/citología , Persona de Mediana Edad , Transporte de Proteínas , Solubilidad , Agua
20.
J Drugs Dermatol ; 12(6): 658-63, 2013 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-23839182

RESUMEN

BACKGROUND: Doxycycline calcium (WC2055) is a drug substance with a possible role in the treatment of acne. The objective of this study was to evaluate the safety and efficacy of three doses of doxycycline calcium tablets compared with placebo in the treatment of moderate to severe inflammatory facial acne vulgaris. METHODS: This was a randomized, double-blind, phase 2 dose-ranging study in subjects with moderate to severe inflammatory acne aged 12 years to 45 years. Subjects were randomized to receive doxycycline calcium tablets 0.6, 1.2, or 2.4 mg/kg/day or placebo, and instructed to take their tablets once daily for 12 weeks, in the evening at least 1 hour before or 2 hours after mealtime. The primary efficacy variables were the dichotomized Investigator's Global Assessment score (success or failure) at week 12 (success defined as ≥ 2 score decrease from baseline) and the absolute change from baseline to week 12 in inflammatory lesion count. RESULTS: A dose-response effect was seen with doxycycline calcium formulation in subjects with moderate to severe inflammatory acne. The highest dose-group (corresponding to approximately 2.4 mg/kg/day) showed a statistically significant difference from placebo. The dose-response effect was confirmed by logistic regression analysis for both treatment success and incidence of gastrointestinal adverse events. A limitation of this study is that safety and efficacy were only studied on moderate to severe inflammatory acne. Also, the study was not prospectively powered to show efficacy differences. CONCLUSION: Doxycycline calcium shows a dose-response effect in reducing inflammatory lesions in subjects with moderate to severe inflammatory acne.


Asunto(s)
Acné Vulgar/tratamiento farmacológico , Antibacterianos/uso terapéutico , Doxiciclina/uso terapéutico , Inflamación/tratamiento farmacológico , Acné Vulgar/patología , Adolescente , Adulto , Antibacterianos/administración & dosificación , Antibacterianos/efectos adversos , Niño , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Doxiciclina/administración & dosificación , Doxiciclina/efectos adversos , Cara , Femenino , Humanos , Inflamación/patología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Adulto Joven
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