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Magnetars are neutron stars with extremely strong magnetic fields (1013 to 1015 gauss)1,2, which episodically emit X-ray bursts approximately 100 milliseconds long and with energies of 1040 to 1041 erg. Occasionally, they also produce extremely bright and energetic giant flares, which begin with a short (roughly 0.2 seconds), intense flash, followed by fainter, longer-lasting emission that is modulated by the spin period of the magnetar3,4 (typically 2 to 12 seconds). Over the past 40 years, only three such flares have been observed in our local group of galaxies3-6, and in all cases the extreme intensity of the flares caused the detectors to saturate. It has been proposed that extragalactic giant flares are probably a subset7-11 of short γ-ray bursts, given that the sensitivity of current instrumentation prevents us from detecting the pulsating tail, whereas the initial bright flash is readily observable out to distances of around 10 to 20 million parsecs. Here we report X-ray and γ-ray observations of the γ-ray burst GRB 200415A, which has a rapid onset, very fast time variability, flat spectra and substantial sub-millisecond spectral evolution. These attributes match well with those expected for a giant flare from an extragalactic magnetar12, given that GRB 200415A is directionally associated13 with the galaxy NGC 253 (roughly 3.5 million parsecs away). The detection of three-megaelectronvolt photons provides evidence for the relativistic motion of the emitting plasma. Radiation from such rapidly moving gas around a rotating magnetar may have generated the rapid spectral evolution that we observe.
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Soft γ-ray repeaters exhibit bursting emission in hard X-rays and soft γ-rays. During the active phase, they emit random short (milliseconds to several seconds long), hard-X-ray bursts, with peak luminosities1 of 1036 to 1043 erg per second. Occasionally, a giant flare with an energy of around 1044 to 1046 erg is emitted2. These phenomena are thought to arise from neutron stars with extremely high magnetic fields (1014 to 1015 gauss), called magnetars1,3,4. A portion of the second-long initial pulse of a giant flare in some respects mimics short γ-ray bursts5,6, which have recently been identified as resulting from the merger of two neutron stars accompanied by gravitational-wave emission7. Two γ-ray bursts, GRB 051103 and GRB 070201, have been associated with giant flares2,8-11. Here we report observations of the γ-ray burst GRB 200415A, which we localized to a 20-square-arcmin region of the starburst galaxy NGC 253, located about 3.5 million parsecs away. The burst had a sharp, millisecond-scale hard spectrum in the initial pulse, which was followed by steady fading and softening over 0.2 seconds. The energy released (roughly 1.3 × 1046 erg) is similar to that of the superflare5,12,13 from the Galactic soft γ-ray repeater SGR 1806-20 (roughly 2.3 × 1046 erg). We argue that GRB 200415A is a giant flare from a magnetar in NGC 253.
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Long-duration γ-ray bursts (GRBs) originate from ultra-relativistic jets launched from the collapsing cores of dying massive stars. They are characterized by an initial phase of bright and highly variable radiation in the kiloelectronvolt-to-megaelectronvolt band, which is probably produced within the jet and lasts from milliseconds to minutes, known as the prompt emission1,2. Subsequently, the interaction of the jet with the surrounding medium generates shock waves that are responsible for the afterglow emission, which lasts from days to months and occurs over a broad energy range from the radio to the gigaelectronvolt bands1-6. The afterglow emission is generally well explained as synchrotron radiation emitted by electrons accelerated by the external shock7-9. Recently, intense long-lasting emission between 0.2 and 1 teraelectronvolts was observed from GRB 190114C10,11. Here we report multi-frequency observations of GRB 190114C, and study the evolution in time of the GRB emission across 17 orders of magnitude in energy, from 5 × 10-6 to 1012 electronvolts. We find that the broadband spectral energy distribution is double-peaked, with the teraelectronvolt emission constituting a distinct spectral component with power comparable to the synchrotron component. This component is associated with the afterglow and is satisfactorily explained by inverse Compton up-scattering of synchrotron photons by high-energy electrons. We find that the conditions required to account for the observed teraelectronvolt component are typical for GRBs, supporting the possibility that inverse Compton emission is commonly produced in GRBs.
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OBJECTIVES: Hospices are regarded as gold standard providers of end-of-life care. The term hospice, however, is broadly used, and can describe a type of care offered in a variety of health care services (e.g. nursing homes). It thus becomes complex for families to decide between services. We aimed to review the evidence around the experience of family carers of people with dementia accessing in-patient hospice settings for end-of-life care. METHOD: We registered the review protocol on PROSPERO. We used PerSPE(C)TiF to systematically organise our search strategy. The evidence was reviewed across six databases: PubMed, EMBASE, PsycINFO, ASSIA, ISI Web, and CINAHL. We used meta-ethnography as per the eMERGe guidance for data interpretation. RESULTS: Four studies were included. Two third-order constructs were generated through meta-ethnography: expectations of care and barriers to quality of care. We found that carers had expectations of care, and these could change over time. If discussion was not held with hospice staff early on, the carers could experience reduced care quality due to unmatched expectations. Unmatched expectations acted as barriers to care and these were found in terms of carers not feeling adequately supported, and/or having the person discharged from hospice, which would entail increased care responsibility for carers. CONCLUSION: In view of an increase in new dementia cases over time and with hospice services being under pressure, integrating palliative care services within community-based models of care is key to reducing the risk of having inadequate and under resourced services for people with dementia.
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Demencia , Hospitales para Enfermos Terminales , Cuidado Terminal , Humanos , Cuidadores , Antropología Cultural , Demencia/terapiaRESUMEN
BACKGROUND: There is a trend toward increased surgical treatment of displaced clavicle fractures in the adolescent population presumably because of extrapolation of adult-derived best practice guidelines. The purpose of this study was to compare return to sport between nonoperative and operative treatment of clavicle fractures in high school athletes. METHODS: A retrospective review of clavicle fractures sustained in scholastic athletes participating in school-sponsored athletics in the upstate South Carolina was performed from 2015 to 2019. Injury circumstances, demographics, radiographs, treatment, and return to sport data were documented for all patients. Radiographs were evaluated for fracture location, comminution, displacement, shortening, and angulation. Patients were followed until complete return to sport, and results were compared based on sport participation, injury mechanism, fracture morphology, treatment type, and time to return to sport. RESULTS: Forty-seven patients (44 were male; average age 15.6 years) were included who all returned to sport within the original or subsequent season. Thirty-six patients (73%) were managed conservatively (30 middle third fractures, 4 medial third fractures, 2 distal third fractures), whereas 11 were managed surgically (11 middle third fractures). Eighty-one percent of fractures occured in collision athletes (55% in football). There was no difference in time loss based on participating in collision vs. noncontact sports (P = .4). Conservatively managed fractures returned to sport faster (61 ± 38 days vs. 100 ± 49 days; P = .008) compared with surgically managed patients. Fracture displacement ≥100% (100 ± 51 days vs. 54 ± 27 days; P = .001), greater comminution (128 ± 50 days vs. 59 ± 31 days; P = .001), and angulation (86 ± 52 days vs. 54 ± 22 days; P = .001) all were statistically significant for slower return to sport. Athletes presenting with clavicular shortening <2 cm returned to sport within a similar time frame as athletes with ≥2 cm (P = 0.1). CONCLUSION: Our results show that adolescent athletes with clavicular fractures predictably return to athletics, including collision sports. Athletes conservatively managed returned 40% faster than those with surgery. However, this appears to be associated with the severity and complexity of fractures treated surgically. This study provides evidence to counsel adolescent athletes following clavicular fractures on return to sport expectations.
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Clavícula , Deportes , Adolescente , Adulto , Atletas , Clavícula/diagnóstico por imagen , Humanos , Masculino , Estudios Retrospectivos , Volver al DeporteRESUMEN
QUESTION: Does Nitisinone prevent the clinical progression of the Alkaptonuria? FINDINGS: In this observational study on 39 patients, 2â¯mg of daily nitisinone inhibited ochronosis and significantly slowed the progression of AKU over a three-year period. MEANING: Nitisinone is a beneficial therapy in Alkaptonuria. BACKGROUND: Nitisinone decreases homogentisic acid (HGA), but has not been shown to modify progression of Alkaptonuria (AKU). METHODS: Thirty-nine AKU patients attended the National AKU Centre (NAC) in Liverpool for assessments and treatment. Nitisinone was commenced at V1 or baseline. Thirty nine, 34 and 22 AKU patients completed 1, 2 and 3â¯years of monitoring respectively (V2, V3 and V4) in the VAR group. Seventeen patients also attended a pre-baseline visit (V0) in the VAR group. Within the 39 patients, a subgroup of the same ten patients attended V0, V1, V2, V3 and V4 visits constituting the SAME Group. Severity of AKU was assessed by calculation of the AKU Severity Score Index (AKUSSI) allowing comparison between the pre-nitisinone and the nitisinone treatment phases. RESULTS: The ALL (sum of clinical, joint and spine AKUSSI features) AKUSSI rate of change of scores/patient/month, in the SAME group, was significantly lower at two (0.32⯱â¯0.19) and three (0.15⯱â¯0.13) years post-nitisinone when compared to pre-nitisinone (0.65⯱â¯0.15) (pâ¯<â¯.01 for both comparisons). Similarly, the ALL AKUSSI rate of change of scores/patient/month, in the VAR group, was significantly lower at one (0.16⯱â¯0.08) and three (0.19⯱â¯0.06) years post-nitisinone when compared to pre-nitisinone (0.59⯱â¯0.13) (pâ¯<â¯.01 for both comparisons). Combined ear and ocular ochronosis rate of change of scores/patient/month was significantly lower at one, two and three year's post-nitisinone in both VAR and SAME groups compared with pre-nitisinone (pâ¯<â¯.05). CONCLUSION: This is the first indication that a 2â¯mg dose of nitisinone slows down the clinical progression of AKU. Combined ocular and ear ochronosis progression was arrested by nitisinone.
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Alcaptonuria/tratamiento farmacológico , Ciclohexanonas/administración & dosificación , Nitrobenzoatos/administración & dosificación , Ocronosis/tratamiento farmacológico , 4-Hidroxifenilpiruvato Dioxigenasa/metabolismo , Alcaptonuria/epidemiología , Alcaptonuria/metabolismo , Alcaptonuria/patología , Progresión de la Enfermedad , Femenino , Ácido Homogentísico/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Ocronosis/epidemiología , Ocronosis/metabolismo , Ocronosis/patología , Reino UnidoRESUMEN
OBJECTIVE: To investigate the in vivo role of the IRE1/XBP1 unfolded protein response (UPR) signaling pathway in cartilage. DESIGN: Xbp1(flox/flox).Col2a1-Cre mice (Xbp1(CartΔEx2)), in which XBP1 activity is ablated specifically from cartilage, were analyzed histomorphometrically by Alizarin red/Alcian blue skeletal preparations and X-rays to examine overall bone growth, histological stains to measure growth plate zone length, chondrocyte organization, and mineralization, and immunofluorescence for collagen II, collagen X, and IHH. Bromodeoxyuridine (BrdU) and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) analyses were used to measure chondrocyte proliferation and cell death, respectively. Chondrocyte cultures and microdissected growth plate zones were analyzed for expression profiling of chondrocyte proliferation or endoplasmic reticulum (ER) stress markers by Quantitative PCR (qPCR), and of Xbp1 mRNA splicing by RT-PCR to monitor IRE1 activation. RESULTS: Xbp1(CartΔEx2) displayed a chondrodysplasia involving dysregulated chondrocyte proliferation, growth plate hypertrophic zone shortening, and IRE1 hyperactivation in chondrocytes. Deposition of collagens II and X in the Xbp1(CartΔEx2) growth plate cartilage indicated that XBP1 is not required for matrix protein deposition or chondrocyte hypertrophy. Analyses of mid-gestation long bones revealed delayed ossification in Xbp1(CartΔEx2) embryos. The rate of chondrocyte cell death was not significantly altered, and only minimal alterations in the expression of key markers of chondrocyte proliferation were observed in the Xbp1(CartΔEx2) growth plate. IRE1 hyperactivation occurred in Xbp1(CartΔEx2) chondrocytes but was not sufficient to induce regulated IRE1-dependent decay (RIDD) or a classical UPR. CONCLUSION: Our work suggests roles for XBP1 in regulating chondrocyte proliferation and the timing of mineralization during endochondral ossification, findings which have implications for both skeletal development and disease.
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Calcificación Fisiológica/fisiología , Cartílago Articular/patología , Condrocitos/patología , Proteínas de Unión al ADN/genética , Eliminación de Gen , Osteocondrodisplasias/patología , Transducción de Señal/fisiología , Factores de Transcripción/genética , Animales , Apoptosis/fisiología , Cartílago Articular/fisiopatología , Proliferación Celular/fisiología , Proteínas de Unión al ADN/fisiología , Modelos Animales de Enfermedad , Estrés del Retículo Endoplásmico/fisiología , Placa de Crecimiento/patología , Placa de Crecimiento/fisiopatología , Proteínas de la Membrana/genética , Proteínas de la Membrana/fisiología , Ratones , Ratones Transgénicos , Osteocondrodisplasias/fisiopatología , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/fisiología , Factores de Transcripción del Factor Regulador X , Transducción de Señal/genética , Factores de Transcripción/fisiología , Proteína 1 de Unión a la X-BoxRESUMEN
A cornerstone of Einstein's special relativity is Lorentz invariance-the postulate that all observers measure exactly the same speed of light in vacuum, independent of photon-energy. While special relativity assumes that there is no fundamental length-scale associated with such invariance, there is a fundamental scale (the Planck scale, l(Planck) approximately 1.62 x 10(-33) cm or E(Planck) = M(Planck)c(2) approximately 1.22 x 10(19) GeV), at which quantum effects are expected to strongly affect the nature of space-time. There is great interest in the (not yet validated) idea that Lorentz invariance might break near the Planck scale. A key test of such violation of Lorentz invariance is a possible variation of photon speed with energy. Even a tiny variation in photon speed, when accumulated over cosmological light-travel times, may be revealed by observing sharp features in gamma-ray burst (GRB) light-curves. Here we report the detection of emission up to approximately 31 GeV from the distant and short GRB 090510. We find no evidence for the violation of Lorentz invariance, and place a lower limit of 1.2E(Planck) on the scale of a linear energy dependence (or an inverse wavelength dependence), subject to reasonable assumptions about the emission (equivalently we have an upper limit of l(Planck)/1.2 on the length scale of the effect). Our results disfavour quantum-gravity theories in which the quantum nature of space-time on a very small scale linearly alters the speed of light.
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OBJECTIVE: To evaluate procedure-related adverse events, post-procedure menstrual bleeding status, and surgical re-intervention in women with a sounded uterine length > 10 cm compared to women with a sounded uterine length ≤ 10 cm who underwent the NovaSure endometrial ablation procedure. METHODS: We conducted a retrospective cohort study of 188 women from a Canadian community-based gynaecology practice. Eighty-seven women had a sounded uterine length > 10 cm, and 101 patients had a sounded length ≤ 10 cm. Procedure-related adverse events, post-procedure menstrual bleeding status, and surgical re-interventions were compared between groups. RESULTS: Mean uterine sounding lengths were 11.0 ± 0.6 cm and 8.9 ± 0.8 cm in the > 10 cm and ≤ 10 cm groups, respectively. There were no differences between the groups in demographic characteristics or gynaecologic history, with the exception of higher BMI in the > 10 cm group and a greater prevalence of dysmenorrhea in the ≤ 10 cm group. Overall, 44.1% of all participants had been unsuccessfully treated with hormonal therapy, and 20.7% had failed non-hormonal treatment before the ablation procedure. The remaining 35.2% of participants had declined alternative therapy and proceeded directly to endometrial ablation. No serious procedure-related adverse events occurred in either group. Menstrual bleeding status at follow-up at 30.4 ± 15.3 months (> 10 cm group) and 30.5 ± 15.5 months (≤ 10 cm group) was not different between the groups (P = 0.85). In women who did not undergo surgical re-intervention after the initial ablation, amenorrhea was reported by 51.9% in the > 10 cm group and 65.9% in the ≤ 10 cm group. CONCLUSION: The NovaSure endometrial ablation procedure was associated with successful menstrual bleeding outcomes in women with sounded uterine length > 10 cm. No serious procedure-related adverse events occurred, and the need for surgical re-intervention was low. There was no significant difference in bleeding rates between the > 10 cm and ≤ 10 cm uterine length cohorts.
Objectif : Comparer, chez des femmes ayant subi une ablation de l'endomètre au moyen de la technique NovaSure et présentant une longueur utérine déterminée par hystérométrie de plus de 10 cm ou de 10 cm ou moins, les événements indésirables associés à l'intervention, l'état des saignements menstruels à la suite de l'intervention et la nécessité de procéder à une nouvelle intervention chirurgicale. Méthodes : Nous avons mené une étude de cohorte rétrospective qui portait sur 188 femmes ayant fréquenté une pratique gynécologique communautaire au Canada. Quatre-vingt-sept de ces femmes présentaient une longueur utérine déterminée par hystérométrie de plus de 10 cm, tandis que les 101 autres présentaient une longueur utérine déterminée par hystérométrie de 10 cm ou moins. Les événements indésirables associés à l'intervention, l'état des saignements menstruels à la suite de l'intervention et la nécessité de procéder à une nouvelle intervention chirurgicale sont les paramètres qui ont été comparés chez ces deux groupes de femmes. Résultats : Les longueurs utérines moyennes déterminées par hystérométrie ont été de 11,0 ± 0,6 cm et de 8,9 ± 0,8 cm au sein des groupes « > 10 cm ¼ et « ≤ 10 cm ¼, respectivement. Aucune différence n'a été constatée entre les groupes en matière de caractéristiques démographiques ou d'antécédents gynécologiques, exception faite d'un IMC accru au sein du groupe « > 10 cm ¼ et d'une prévalence accrue de dysménorrhée au sein du groupe « ≤ 10 cm ¼. De façon globale, 44,1 % de toutes les participantes avaient connu l'échec de l'hormonothérapie et 20,7 % avaient connu l'échec d'un traitement non hormonal avant la tenue de l'ablation. Les participantes composant les autres 35,2 % avaient refusé d'avoir recours à un traitement de rechange et décidé de subir directement une ablation de l'endomètre. Aucun événement indésirable grave associé à l'intervention ne s'est manifesté dans l'un ou l'autre des groupes. Aucune différence n'a été constatée entre les groupes (P = 0,85) pour ce qui est de l'état des saignements menstruels au moment du suivi à 30,4 ± 15,3 mois (groupe « > 10 cm ¼) et à 30,5 ± 15,5 mois (groupe « ≤ 10 cm ¼). Chez les femmes qui n'ont pas eu à subir une nouvelle intervention chirurgicale à la suite de l'ablation initiale, une aménorrhée a été signalée par 51,9 % des participantes du groupe « > 10 cm ¼ et par 65,9 % des participantes du groupe « ≤ 10 cm ¼. Conclusion : La technique NovaSure d'ablation de l'endomètre a été associée à des issues réussies en matière de saignements menstruels chez les femmes présentant une longueur utérine déterminée par hystérométrie de plus de 10 cm. Aucun événement indésirable grave associé à l'intervention ne s'est manifesté et la nécessité de procéder à une nouvelle intervention chirurgicale était faible. Aucune différence significative n'a été constatée en matière de taux de saignement entre les groupes « > 10 cm ¼ et « ≤ 10 cm ¼.
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Técnicas de Ablación Endometrial/efectos adversos , Técnicas de Ablación Endometrial/métodos , Útero/anatomía & histología , Útero/cirugía , Adulto , Estudios de Cohortes , Femenino , Humanos , Tamaño de los Órganos , Reoperación , Estudios RetrospectivosRESUMEN
A flexible metal-organic framework selectively sorbs para- (pX) over meta-xylene (mX) by synergic restructuring around pX coupled with generation of unused void space upon mX loading. The nature of the structural change suggests more generally that flexible structures which are initially mismatched in terms of fit and capacity to the preferred guest are strong candidates for effective molecular separations.
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Phage Culver, with a siphovirus morphology, was isolated using Gordonia terrae CAG3. Culver is assigned to phage cluster CQ1 based on gene content similarity to actinobacteriophages. Notably, Culver is predicted to encode eight tRNAs, lysin A by two adjacent genes, and, unlike other CQ1 phages, two putative integrase genes.
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The recent incorporation of molecular methods into analyses of social and mating systems has provided evidence that mating patterns often differ from those predicted by group social organization. Based on field studies and paternity analyses at a limited number of sites, African lions are predicted to exhibit a strict within-pride mating system. Extra-group paternity has not been previously reported in African lions; however, observations of extra-group associations among lions inhabiting Etosha National Park in Namibia suggest deviation from the predicted within-pride mating pattern. We analysed variation in 14 microsatellite loci in a population of 164 African lions in Etosha National Park. Genetic analysis was coupled with demographic and observational data to examine pride structure, relatedness and extra-group paternity (EGP). EGP was found to occur in 57% of prides where paternity was analysed (n = 7), and the overall rate of EGP in this population was 41% (n = 34). Group sex ratio had a significant effect on the occurrence of EGP (P < 0.05), indicating that variation in pride-level social structure may explain intergroup variation in EGP. Prides with a lower male-to-female ratio were significantly more likely to experience EGP in this population. The results of this study challenge the current models of African lion mating systems and provide evidence that social structure may not reflect breeding structure in some social mammals.
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Variación Genética , Leones/genética , Conducta Sexual Animal/fisiología , Conducta Social , Animales , Demografía , Femenino , Frecuencia de los Genes , Funciones de Verosimilitud , Leones/fisiología , Masculino , Repeticiones de Microsatélite/genética , Namibia , Observación , Razón de MasculinidadRESUMEN
Respiratory disease is common in dolphins, primarily affecting pulmonary parenchyma and sparing large airways. Over a 10-year period, 4 captive adult bottlenose dolphins succumbed to chronic, progressive respiratory disease with atypical recurrent upper respiratory signs. All dolphins had severe, segmental to circumferential fibrosing tracheitis that decreased luminal diameter. Histologically, tracheal cartilage, submucosa, and mucosa were distorted and replaced by extensive fibrosis and pyogranulomatous inflammation centered on fungal hyphae. In 3 of 4 cases, hyphae were morphologically compatible with Aspergillus spp and confirmed by culture in 2 cases. Amplification of fungal DNA from tracheal tissue was successful in one case, and sequences had approximately 98% homology to Aspergillus fumigatus. The remaining case had fungi compatible with zygomycetes; however, culture and polymerase chain reaction were unsuccessful. Lesions were evaluated immunohistochemically using antibodies specific to Aspergillus spp. Aspergillus-like hyphae labeled positively, while presumed zygomycetes did not. These cases represent a novel manifestation of respiratory mycoses in bottlenose dolphins.
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Aspergilosis/veterinaria , Aspergillus/aislamiento & purificación , Delfín Mular , Traqueítis/veterinaria , Animales , Animales de Zoológico , Aspergilosis/microbiología , Aspergilosis/patología , Aspergillus/clasificación , Aspergillus/genética , ADN de Hongos/genética , Femenino , Hifa , Inmunohistoquímica/veterinaria , Pulmón/microbiología , Pulmón/patología , Masculino , Recurrencia , Análisis de Secuencia de ADN/veterinaria , Tráquea/microbiología , Tráquea/patología , Traqueítis/microbiología , Traqueítis/patologíaRESUMEN
Multiple epiphyseal dysplasia (MED) is a relatively mild and clinically variable osteochondrodysplasia, primarily characterized by delayed and irregular ossification of the epiphyses and early-onset osteoarthritis. Mutations in the genes encoding cartilage oligomeric matrix protein (COMP) and type IX collagen (COL9A2 and COL9A3) have previously been shown to cause different forms of MED (refs. 4-13). These dominant forms of MED (EDM1-3) are caused by mutations in the genes encoding structural proteins of the cartilage extracellular matrix (ECM); these proteins interact with high affinity in vitro. A recessive form of MED (EDM4) has also been reported; it is caused by a mutation in the diastrophic dysplasia sulfate transporter gene (SLC26A). A genomewide screen of family with autosomal-dominant MED not linked to the EDM1-3 genes provides significant genetic evidence for a MED locus on the short arm of chromosome 2 (2p24-p23), and a search for candidate genes identified MATN3 (ref. 18), encoding matrilin-3, within the critical region. Matrilin-3 is an oligomeric protein that is present in the cartilage ECM. We have identified two different missense mutations in the exon encoding the von Willebrand factor A (vWFA) domain of matrilin-3 in two unrelated families with MED (EDM5). These are the first mutations to be identified in any of the genes encoding the matrilin family of proteins and confirm a role for matrilin-3 in the development and homeostasis of cartilage and bone.
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Proteínas de la Matriz Extracelular/genética , Mutación , Osteocondrodisplasias/genética , Factor de von Willebrand/genética , Adulto , Niño , Cromosomas Humanos Par 2/genética , Análisis Mutacional de ADN , Proteínas de la Matriz Extracelular/metabolismo , Femenino , Cabeza Femoral/diagnóstico por imagen , Cabeza Femoral/patología , Ligamiento Genético , Marcadores Genéticos , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/patología , Escala de Lod , Masculino , Proteínas Matrilinas , Persona de Mediana Edad , Osteocondrodisplasias/diagnóstico , Linaje , Mapeo Físico de Cromosoma , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple , Estructura Terciaria de Proteína/genética , RadiografíaRESUMEN
Pseudoachondroplasia (PSACH) and multiple epiphyseal dysplasia (MED) are dominantly inherited chondrodysplasias characterized by short stature and early-onset osteoarthrosis. The disease genes in families with PSACH and MED have been localized to an 800 kilobase interval on the short arm of chromosome 19. Recently the gene for cartilage oligomeric matrix protein (COMP) was localized to chromosome 19p13.1. In three patients with these diseases, we identified COMP mutations in a region of the gene that encodes a Ca++ binding motif. Our data demonstrate that PSACH and some forms of MED are allelic and suggest an essential role for Ca++ binding in COMP structure and function.
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Acondroplasia/genética , Proteínas de la Matriz Extracelular , Glicoproteínas/genética , Mutación , Osteocondrodisplasias/genética , Acondroplasia/diagnóstico por imagen , Acondroplasia/metabolismo , Alelos , Secuencia de Aminoácidos , Secuencia de Bases , Calcio/metabolismo , Calmodulina/genética , Cartílago , Proteína de la Matriz Oligomérica del Cartílago , Mapeo Cromosómico , Cromosomas Humanos Par 19 , ADN Satélite/genética , Factor de Crecimiento Epidérmico/genética , Femenino , Genes Dominantes , Ligamiento Genético , Glicoproteínas/metabolismo , Humanos , Masculino , Proteínas Matrilinas , Datos de Secuencia Molecular , Osteocondrodisplasias/diagnóstico por imagen , Osteocondrodisplasias/metabolismo , Linaje , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple , Radiografía , Secuencias Repetitivas de Ácidos NucleicosRESUMEN
INTRODUCTION: The study objectives were to determine the prevalence and geographic distribution of a dilated cardiomyopathy (DCM)-associated RNA-binding motif protein 20 (RBM20) variant in canine DNA samples submitted for testing and to evaluate the influence of the genotype on cardiac phenotype and lifespan. ANIMALS: Samples from 2136 dogs including 1834 Standard Schnauzers (SSNZ), 266 Giant Schnauzers (GSNZ), and 36 dogs of other breeds. METHODS: The University of Missouri Canine Genetics Laboratory's sample-accession spreadsheet and Orthopedic Foundation for Animals' database were retrospectively reviewed for samples submitted for RBM20 genotyping from November, 2013, through May, 2018. Data analyzed included breed, date of birth, RBM20 genotype (homozygous wild-type, heterozygous variant [HET], or homozygous variant [HOM]), geographic origin of submission, pedigree, cardiac phenotype, and date of death or current age if alive. RESULTS AND DISCUSSION: The RBM20 variant was only detected in SSNZ and GSNZ. A total of 389 SSNZ were variant-positive (prevalence = 21.2%), with 361 HET (19.7%) and 28 HOM (1.5%). Of the HOM SSNZ, DCM was confirmed in 26 of 28 (92.9%), with the remainder lost to follow-up. The median lifespan of HOM SSNZ (3.06 years) was significantly shorter than that for HET (15.11 years) and wild-type (15.18 years) SSNZ. Twenty-six GSNZ were variant-positive (prevalence = 9.8%), with 23 HET (8.6%) and three HOM (1.1%). Nine GSNZ belonged to one family, including the three HOM GSNZ that all had DCM. CONCLUSIONS: The HOM genotype is associated with DCM and premature death in SSNZ and GSNZ.
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Cardiomiopatía Dilatada , Enfermedades de los Perros , Animales , Cardiomiopatía Dilatada/epidemiología , Cardiomiopatía Dilatada/genética , Cardiomiopatía Dilatada/veterinaria , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/genética , Perros , Genotipo , Longevidad , Prevalencia , Motivos de Unión al ARN , Estudios RetrospectivosRESUMEN
BACKGROUND: The lateral step-down test is used by physical therapists (PT) to identify movement faults in patients with patellofemoral pain (PFP). The FPPA is a measure of knee valgus and PTs have access to open source video analysis software and high quality smart phones and video cameras to implement 2D video analysis into practice. The purpose of our study was to determine the reliability of PTs measuring the frontal plane projection angle (FPPA) during the lateral step-down test, and to determine if the FPPA was associated with pain, self-reported knee function and fear of movement. METHODS: Twenty-two subjects (mean age[SD] = 27.8 [6.6] years, females n = 14, males n = 8) with PFP were analyzed by six PTs using 2D video analysis software. The FPPA was measured during the lateral step down test. Numeric Pain Rating Scale (NPRS), Anterior Knee Pain Scale (AKPS) and the Tampa Scale of Kinesiophobia (TSK) were collected. Intraclass correlation (ICC) was used to assess for PT measurement reliability. Correlations between outcomes were calculated using Spearman correlation coefficient and standard error of measurement (SEM) and minimal detectable change (MDC) were reported. RESULTS: Reliability amongst PTs measuring the FPPA was good (ICC [95 %CI] = 0.85 [0.72-0.93]; SEM = 3.33°, MDC = 9.20°). There were no significant correlations (p > 0.05) between FPPA and NPRS(ρ = -0.046), AKPS(ρ = 0.066), or TSK(ρ = -0.204). CONCLUSIONS: Although reliability measuring FPPA was good, the large SEM and MDC associated with this measurement may limit its clinical utility in those with PFP.
Asunto(s)
Síndrome de Dolor Patelofemoral , Fenómenos Biomecánicos , Niño , Femenino , Humanos , Articulación de la Rodilla , Masculino , Dolor , Reproducibilidad de los ResultadosRESUMEN
The development of colorectal cancer, one of the most frequent cancers, is influenced by prostaglandins and fatty acids. Decreased prostaglandin production, seen in mice with mutations in the cyclooxygenase 2 gene or in animals and humans treated with cyclooxygenase inhibitors, prevents or attenuates colon cancer development. There is also a strong correlation between the intake of fatty acids from animal origin and colon cancer. Therefore, the peroxisome proliferator-activated receptor gamma (PPARgamma), a downstream transcriptional mediator for prostaglandins and fatty acids which is highly expressed in the colon may be involved in this process. Activation of PPARgamma by two different synthetic agonists increased the frequency and size of colon tumors in C57BL/6J-APCMin/+ mice, an animal model susceptible to intestinal neoplasia. Tumor frequency was only increased in the colon, and did not change in the small intestine, coinciding with the colon-restricted expression of PPARgamma. Treatment with PPARgamma agonists increased beta-catenin levels both in the colon of C57BL/61-APCMin/+ mice and in HT-29 colon carcinoma cells. Genetic abnormalities in the Wnt/wingless/APC pathway, which enhance the transcriptional activity of the beta-catenin-T-cell factor/lymphoid enhancer factor 1 transcription complex, often underly the development of colon tumors. Our data indicate that PPARgamma activation modifies the development of colon tumors in C57BL/61-APCMin/+ mice.
Asunto(s)
Adenocarcinoma/fisiopatología , Neoplasias Colorrectales/fisiopatología , Receptores Citoplasmáticos y Nucleares/fisiología , Tiazolidinedionas , Transactivadores , Factores de Transcripción/fisiología , Adenocarcinoma/patología , Animales , Cromanos/farmacología , Neoplasias Colorrectales/patología , Ciclooxigenasa 2 , Proteínas del Citoesqueleto/metabolismo , Células HT29 , Humanos , Isoenzimas/metabolismo , Masculino , Proteínas de la Membrana , Ratones , Ratones Endogámicos C57BL , Prostaglandina-Endoperóxido Sintasas/metabolismo , Rosiglitazona , Tiazoles/farmacología , Troglitazona , beta CateninaRESUMEN
Gamma-ray bursts are among the most powerful events in nature. These events release most of their energy as photons with energies in the range from 30 keV to a few MeV, with a smaller fraction of the energy radiated in radio, optical, and soft X-ray afterglows. The data are in general agreement with a relativistic shock model, where the prompt and afterglow emissions correspond to synchrotron radiation from shock-accelerated electrons. Here we report an observation of a high-energy (multi-MeV) spectral component in the burst of 17 October 1994 that is distinct from the previously observed lower-energy gamma-ray component. The flux of the high-energy component decays more slowly and its fluence is greater than the lower-energy component; it is described by a power law of differential photon number index approximately -1 up to about 200 MeV. This observation is difficult to explain with the standard synchrotron shock model, suggesting the presence of new phenomena such as a different non-thermal electron process, or the interaction of relativistic protons with photons at the source.
RESUMEN
Objective: When inserting a dry needle laterally into the upper lumbar spine (L1-L3) there is an increased risk of piercing the kidney; therefore, the objective of this study was to determine a zone of safety for practitioners to needle in the upper lumbar spine.Methods: Ten cadavers were screened for inclusion. L1 spinous process was identified and confirmed with ultrasound imaging. A digital caliper was used to measure laterally at 1.5 cm, 2.0 cm, and 2.5 cm. Dry needles were inserted maximally at each point and a binary decision, yes or no, was made to determine if bony contact was made. Needle depth and abdominal width measurements were also recorded. Safety of the dry needling procedure was interpreted as such if bony contact was made by the needle. If bony contact was made, then it was assumed that the needle cannot advance further into pleura or kidney.Results: Forty-four percent of needles did not make bony contact at 2.5 cm lateral of the L1 spinous process, whereas 22% did not make bony contact at 1.5 cm and 2.0 cm. There was a weak to moderate negative correlation between abdominal width measurements and needle depth at 1.5 cm (-0.48) and 2.0 cm (-0.45), and at 2.5 cm (-0.39).Conclusion: A safety zone of needling less than 2.5 cm is likely safe, but needs to be confirmed with future study. Dry needling 2.5 cm lateral appears more risky due to the higher frequency of not contacting a bony backdrop.