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Instability of the FMR1 repeat, commonly observed in transmissions of premutation alleles (55-200 repeats), is influenced by the size of the repeat, its internal structure and the sex of the transmitting parent. We assessed these three factors in unstable transmissions of 14/3,335 normal (~5 to 44 repeats), 54/293 intermediate (45-54 repeats), and 1561/1,880 premutation alleles. While most unstable transmissions led to expansions, contractions to smaller repeats were observed in all size classes. For normal alleles, instability was more frequent in paternal transmissions and in alleles with long 3' uninterrupted repeat lengths. For premutation alleles, contractions also occurred more often in paternal than maternal transmissions and the frequency of paternal contractions increased linearly with repeat size. All paternal premutation allele contractions were transmitted as premutation alleles, but maternal premutation allele contractions were transmitted as premutation, intermediate, or normal alleles. The eight losses of AGG interruptions in the FMR1 repeat occurred exclusively in contractions of maternal premutation alleles. We propose a refined model of FMR1 repeat progression from normal to premutation size and suggest that most normal alleles without AGG interruptions are derived from contractions of maternal premutation alleles.
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Alelos , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Síndrome del Cromosoma X Frágil/genética , Patrón de Herencia , Expansión de Repetición de Trinucleótido , Femenino , Síndrome del Cromosoma X Frágil/diagnóstico , Síndrome del Cromosoma X Frágil/patología , Expresión Génica , Frecuencia de los Genes , Humanos , Masculino , LinajeRESUMEN
On March 24, 2017, more than 90 experts in blood safety and international development from blood centers, industry, government, and international and nongovernmental organizations gathered in Arlington, Virginia, for the Third International Blood Safety Forum, cosponsored by America's Blood Centers and Global Healing. This report summarizes presentations and major conclusions. The meeting explored ways to increase access to affordable, safe blood for low- and lower-middle-income countries (LMICs) in an era when funding from the US President's Emergency Plan for AIDS Relief (PEPFAR) and the Global Fund has been redirected from preventing the spread of human immunodeficiency virus (HIV) to diagnosing and treating the 25 million-plus people living with HIV in LMICs. More effective management systems must be developed to improve cost recovery for blood. While blood systems become more sustainable, continued investment is required to keep them operating. The traditional model of large grants from bilateral and multilateral donors will need to be supplemented (or replaced) with public-private partnerships and nongovernmental investment. A continued emphasis on quality is fundamental. Blood systems must build quality programs, based on accepted standards, including hospitals, clinics, and rural health care providers to ensure proper and safe use of blood. Proposals to resolve health care inequities between LMICs and high-income countries (HICs) must include helping LMICs to define sustainable national policies and practices for blood availability and utilization to suit local contexts. The blood safety lexicon should be revised to include availability, accessibility, and affordability of safe blood and blood products as the goal of all blood safety initiatives.
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Seguridad de la Sangre/normas , Educación , Seguridad de la Sangre/economía , Países en Desarrollo/economía , Salud Global/educación , Política de Salud , HumanosRESUMEN
BACKGROUND: Ebolaviruses have been known to cause deadly disease in humans for 40 years and have recently been demonstrated in West Africa to be able to cause large outbreaks. Four Ebolavirus species cause severe disease associated with high mortality in humans. Reston viruses are the only Ebolaviruses that do not cause disease in humans. Conserved amino acid changes in the Reston virus protein VP24 compared to VP24 of other Ebolaviruses have been suggested to alter VP24 binding to host cell karyopherins resulting in impaired inhibition of interferon signalling, which may explain the difference in human pathogenicity. Here we used protein structural analysis and molecular dynamics to further elucidate the interaction between VP24 and KPNA5. RESULTS: As a control experiment, we compared the interaction of wild-type and R137A-mutant (known to affect KPNA5 binding) Ebola virus VP24 with KPNA5. Results confirmed that the R137A mutation weakens direct VP24-KPNA5 binding and enables water molecules to penetrate at the interface. Similarly, Reston virus VP24 displayed a weaker interaction with KPNA5 than Ebola virus VP24, which is likely to reduce the ability of Reston virus VP24 to prevent host cell interferon signalling. CONCLUSION: Our results provide novel molecular detail on the interaction of Reston virus VP24 and Ebola virus VP24 with human KPNA5. The results indicate a weaker interaction of Reston virus VP24 with KPNA5 than Ebola virus VP24, which is probably associated with a decreased ability to interfere with the host cell interferon response. Hence, our study provides further evidence that VP24 is a key player in determining Ebolavirus pathogenicity.
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Ebolavirus/patogenicidad , Simulación de Dinámica Molecular , Proteínas Virales/metabolismo , Ebolavirus/metabolismo , Fiebre Hemorrágica Ebola/metabolismo , Humanos , Conformación Proteica , Proteínas Virales/química , alfa Carioferinas/metabolismoRESUMEN
PURPOSE: Primary ovarian insufficiency before the age of 40 years affects 1% of the female population and is characterized by permanent cessation of menstruation. Genetic causes include FMR1 expansion mutations. Previous studies have estimated mutation prevalence in clinical referrals for primary ovarian insufficiency, but these are likely to be biased as compared with cases in the general population. The prevalence of FMR1 expansion mutations in early menopause (between the ages of 40 and 45 years) has not been published. METHODS: We studied FMR1 CGG repeat number in more than 2,000 women from the Breakthrough Generations Study who underwent menopause before the age of 46 years. We determined the prevalence of premutation (55-200 CGG repeats) and intermediate (45-54 CGG repeats) alleles in women with primary ovarian insufficiency (n = 254) and early menopause (n = 1,881). RESULTS: The prevalence of the premutation was 2.0% in primary ovarian insufficiency, 0.7% in early menopause, and 0.4% in controls, corresponding to odds ratios of 5.4 (95% confidence interval = 1.7-17.4; P = 0.004) for primary ovarian insufficiency and 2.0 (95% confidence interval = 0.8-5.1; P = 0.12) for early menopause. Combining primary ovarian insufficiency and early menopause gave an odds ratio of 2.4 (95% confidence interval = 1.02-5.8; P = 0.04). Intermediate alleles were not significant risk factors for either early menopause or primary ovarian insufficiency. CONCLUSION: FMR1 premutations are not as prevalent in women with ovarian insufficiency as previous estimates have suggested, but they still represent a substantial cause of primary ovarian insufficiency and early menopause.
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Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Menopausia Prematura/genética , Insuficiencia Ovárica Primaria/genética , Adulto , Estudios de Casos y Controles , Femenino , Variación Genética , Humanos , Modelos Lineales , Modelos Logísticos , Persona de Mediana Edad , Insuficiencia Ovárica Primaria/diagnóstico , Estudios Prospectivos , Expansión de Repetición de Trinucleótido , Reino UnidoRESUMEN
Immunohistochemistry (IHC) is a testing methodology that is widely used for large number of diagnostic, prognostic, and predictive biomarkers. Although IHC is a qualitative methodology, in addition to threshold-based stratification (positive vs. negative), the increasing levels of expression of some of these biomarkers often lead to more intense staining, which published evidence linked to specific diagnosis, prognosis, and responses to therapy. It is essential that the descriptive thresholds between positive and negative staining, as well as between frequently used graded categories of staining intensity (eg, 1+, 2+, 3+) are standardized and reproducible. Histo-score (H-score) is a frequently used scoring system that utilizes these categories. Our study introduces categorization of the cutoff points between positive and negative results and graded categories of staining intensity for nuclear IHC biomarker assays based on color interaction between hematoxylin and diaminobenzidine (DAB); the Blue-brown Color H-score (BBC-HS). Six cases of diffuse large B-cell lymphoma were stained for a nuclear marker MUM1. The staining was assessed by H-score by 12 readers. Short tutorial and illustrated instructions were provided to readers. The novel scoring system in this study uses the interaction between DAB (DAB, brown stain) and hematoxylin (blue counterstain) to set thresholds between "0" (negative nuclei), "1+" (weakly positive nuclei), "2+" (moderately positive nuclei), and "3+" (strongly positive nuclei). The readers recorded scores for 300 cells. Krippendorff alpha (K-alpha) and intraclass correlation coefficient (ICC) were calculated. We have also assessed if reliability improved when counting the first 100 cells, first 200 cells, and for the total 300 cells using K-alpha and ICC. To assess the performance of each individual reader, the mean H-score and percent positive score (PPS) for each case was calculated, and the bias was calculated between each reader's score and the mean. K-alpha was 0.86 for H-score and 0.76 for PPS. ICC was 0.96 for H-score and 0.92 for PPS. The biases for H-score ranged from -58 to 41, whereas for PPS it ranged from -27% to 33%. Overall, most readers showed very low bias. Two readers were consistently underscoring and 2 were consistently overscoring compared with the mean. For nuclear IHC biomarker assays, our newly proposed cutoffs provide highly reliable/reproducible results between readers for positive and negative results and graded categories of staining intensity using existing morphologic parameters. BBC-HS is easy to teach and is applicable to both human eye and image analysis. BBC-HS application should facilitate the development of new reliable/reproducible scoring schemes for IHC biomarkers.
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Núcleo Celular , Humanos , Hematoxilina , Reproducibilidad de los Resultados , Inmunohistoquímica , Núcleo Celular/metabolismoRESUMEN
Background: Approximately 1 in 1000 men have a 47,XYY karyotype. Previous publications have presented cases of infertile XYY men and have suggested that the additional Y chromosome may cause disrupted meiosis leading to sperm apoptosis. The purpose of the current study was to determine whether XYY men are over-represented in infertility cohorts. Methods: In this paper, an ongoing infertility cohort was evaluated for Y chromosome microdeletions using the MLPA technique and the data from the first 2000 referrals were recorded. Moreover, the MLPA technique detected 47,XYY karyotypes. Results: Four XYY individuals were identified within the cohort. One of the four XYY men was shown to have an apparent gr/gr partial AZFc deletion on both Y chromosomes while Sertoli cell only syndrome was detected in another case. The other two cases (out of 2000) might, therefore, represent an incidental finding. Conclusion: The gr/gr deletion is not detectable by the multiplex PCR method; therefore, there might be additional explanations for the fertility problems of infertile XYY men reported in previously published articles. It seems that among other cases, their XYY karyotype may be coincidental, rather than causative of their fertility issues.
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Placental histopathology provides insights, or "snapshots", into relevant antenatal factors that could elevate the risk of perinatal brain injury. We present a systematic review and meta-analysis comparing frequencies of adverse neurological outcomes in infants born to women with placental abruption versus without abruption. Records were sourced from MEDLINE, Embase, and the CENTRAL Trials Registry from 1946 to December 2019. Studies followed the PRISMA guidelines and compared frequencies of neurodevelopmental morbidities in infants born to pregnant women with placental abruption (exposure) versus women without placental abruption (comparator). The primary endpoint was cerebral palsy. Periventricular and intraventricular (both severe and any grades of IVH) and any histopathological neuronal damage were the secondary endpoints. Study methodologic quality was assessed by the Ottawa-Newcastle scale. Estimated odds ratios (OR) and hazards ratio (HR) were derived according to study design. Data were meta-analyzed using a random effects model expressed as pooled effect sizes and 95% confidence intervals. We included eight observational studies in the review, including 1245 infants born to women with placental abruption. Results of the random effects meta-analysis show that the odds of infants born to pregnant women with placental abruption who experience cerebral palsy is higher than in infants born to pregnant women without placental abruption (OR 5.71 95% CI (1.17, 27.91); I2 = 84.0%). There is no statistical difference in the odds of infants born to pregnant women with placental abruption who experience severe IVH (grade 3+) (OR 1.20 95% CI (0.46, 3.11); I2 = 35.8%) and any grade of IVH (OR 1.20 95% CI (0.62, 2.32); I2 = 32.3%) vs. women without placental abruption. There is no statistically significant difference in the odds of infants born to pregnant women with placental abruption who experience PVL vs. pregnant women without placental abruption (OR 6.51 95% CI (0.94, 45.16); I2 = 0.0%). Despite our meta-analysis suggesting increased odds of cerebral palsy in infants born to pregnant women with placental abruption versus without abruption, this finding should be interpreted cautiously, given high heterogeneity and overall poor quality of the included studies.
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Unverricht-Lundborg disease (EPM1A), also known as Baltic myoclonus, is the most common form of progressive myoclonic epilepsy. It is inherited as an autosomal recessive trait, due to mutations in the Cystatin-B gene promoter region. Although there is much work on rodent models of this disease, there is very little published neuropathology in patients with EPM1A. Here, we present the neuropathology of a patient with genetically confirmed EPM1A, who died at the age of 76. There was atrophy and gliosis affecting predominantly the cerebellum, frontotemporal cortex, hippocampus and thalamus. We have identified neuronal cytoplasmic inclusions containing the lysosomal proteins, Cathepsin-B and CD68. These inclusions also showed immunopositivity to both TDP-43 and FUS, in some cases associated with an absence of normal neuronal nuclear TDP-43 staining. There were also occasional ubiquitinylated neuronal intranuclear inclusions, some of which were FUS immunopositive. This finding is consistent with neurodegeneration in EPM1A as at least a partial consequence of lysosomal damage to neurons, which have reduced Cystatin-B-related neuroprotection. It also reveals a genetically defined neurodegenerative disease with both FUS and TDP-43 related pathology.
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Cuerpos de Inclusión/patología , Cuerpos de Inclusión Intranucleares/patología , Neuronas/patología , Síndrome de Unverricht-Lundborg/patología , Anciano , Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Atrofia/patología , Cistatina B/genética , Cistatina B/metabolismo , Proteínas de Unión al ADN/metabolismo , Resultado Fatal , Femenino , Humanos , Cuerpos de Inclusión/metabolismo , Cuerpos de Inclusión Intranucleares/metabolismo , Mutación/genética , Neuronas/metabolismo , Proteína FUS de Unión a ARN/metabolismo , Síndrome de Unverricht-Lundborg/genética , Síndrome de Unverricht-Lundborg/metabolismoRESUMEN
Currently, there is no compendial-level method to assess dissolution of particulate systems administered in the periodontal pocket. This work seeks to develop dissolution methods for extended release poly(lactic-co-glycolic acid) (PLGA) microspheres applied in the periodontal pocket. Arestin®, PLGA microspheres containing minocycline hydrochloride (MIN), is indicated for reduction of pocket depth in adult periodontitis. Utilizing Arestin® as a model product, two dissolution methods were developed: a dialysis set-up using USP apparatus 4 and a novel apparatus fabricated to simulate in vivo environment of the periodontal pocket. In the biorelevant method, the microspheres were dispersed in 250 µL of simulated gingival crevicular fluid (sGCF) which was enclosed in a custom-made dialysis enclosure. sGCF was continuously delivered to the device at a biorelevant flow rate and was collected daily for drug content analysis using UPLC. Both methods could discriminate release characteristics of a panel of MIN-loaded PLGA microspheres that differed in composition and process conditions. A mechanistic model was developed, which satisfactorily explained the release profiles observed using both dissolution methods. The developed methods may have the potential to be used as routine quality control tools to ensure batch-to-batch consistency and to support evaluation of bioequivalence for periodontal microspheres.
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Antibacterianos , Minociclina , Adulto , Antibacterianos/uso terapéutico , Humanos , Microesferas , Diálisis Renal , SolubilidadRESUMEN
OBJECTIVE: To identify modifying genes that explains the risk of fragile X-associated primary ovarian insufficiency (FXPOI). DESIGN: Gene-based, case/control association study, followed by a functional screen of highly ranked genes using a Drosophila model. SETTING: Participants were recruited from academic and clinical settings. PATIENT(S): Women with a premutation (PM) who experienced FXPOI at the age of 35 years or younger (n = 63) and women with a PM who experienced menopause at the age of 50 years or older (n = 51) provided clinical information and a deoxyribonucleic acid sample for whole genome sequencing. The functional screen was on the basis of Drosophila TRiP lines. INTERVENTION(S): Clinical information and a DNA sample were collected for whole genome sequencing. MAIN OUTCOME MEASURES: A polygenic risk score derived from common variants associated with natural age at menopause was calculated and associated with the risk of FXPOI. Genes associated with the risk of FXPOI were identified on the basis of the P-value from gene-based association test and an altered level of fecundity when knocked down in the Drosophila PM model. RESULTS: The polygenic risk score on the basis of common variants associated with natural age at menopause explained approximately 8% of the variance in the risk of FXPOI. Further, SUMO1 and KRR1 were identified as possible modifying genes associated with the risk of FXPOI on the basis of an untargeted gene analysis of rare variants. CONCLUSIONS: In addition to the large genetic effect of a PM on ovarian function, the additive effects of common variants associated with natural age at menopause and the effect of rare modifying variants appear to play a role in FXPOI risk.
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Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Menopausia/genética , Mutación , Ovario/fisiopatología , Insuficiencia Ovárica Primaria/genética , Adulto , Factores de Edad , Animales , Animales Modificados Genéticamente , Estudios de Casos y Controles , Drosophila melanogaster/genética , Femenino , Fertilidad/genética , Antecedentes Genéticos , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Humanos , Persona de Mediana Edad , Fenotipo , Insuficiencia Ovárica Primaria/diagnóstico , Insuficiencia Ovárica Primaria/fisiopatología , Medición de Riesgo , Factores de RiesgoRESUMEN
BACKGROUND: It is recognized that FMR1 premutation expansions are associated with premature ovarian failure (POF), but the role of smaller repeats at the boundary of premutation and normal is less clear. METHODS: We have therefore investigated the incidence of these intermediate sized FMR1 CGG repeats (35-58 repeats) in a series of 366 women ascertained because of menopause before the age of 40. RESULTS: We found no significant difference in the incidence of intermediates in cases compared with controls. Thus, we were unable to replicate previous studies showing a positive association, despite a significantly larger sample size. CONCLUSIONS: We therefore conclude that intermediate sized FMR1 CGG repeat alleles should not be considered a high-risk factor for POF based on current evidence.
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Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Insuficiencia Ovárica Primaria/etiología , Insuficiencia Ovárica Primaria/genética , Expansión de Repetición de Trinucleótido , Adolescente , Adulto , Alelos , Estudios de Casos y Controles , Niño , Estudios de Cohortes , Femenino , Humanos , Mutación , Adulto JovenRESUMEN
The identification of a trinucleotide (CGG) expansion as the chief mechanism of mutation in Fragile X syndrome in 1991 heralded a new chapter in molecular diagnostic genetics and generated a new perspective on mutational mechanisms in human genetic disease, which rapidly became a central paradigm ("dynamic mutation") as more and more of the common hereditary neurodevelopmental disorders were ascribed to this novel class of mutation. The progressive expansion of a CGG repeat in the FMR1 gene from "premutation" to "full mutation" provided an explanation for the "Sherman paradox," just as similar expansion mechanisms in other genes explained the phenomenon of "anticipation" in their pathogenesis. Later, FMR1 premutations were unexpectedly found associated with two other distinct phenotypes: primary ovarian insufficiency and tremor-ataxia syndrome. This review will provide a historical perspective on procedures for testing and reporting of Fragile X syndrome and associated disorders, and the population genetics of FMR1 expansions, including estimates of prevalence and the influence of AGG interspersions on the rate and probability of expansion.
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OBJECTIVE: To analyze the clinical syndromes and inheritance patterns of multiplex families with epilepsy toward the ultimate aim of uncovering the underlying molecular genetic basis. METHODS: Following the referral of families with 2 or more relatives with epilepsy, individuals were classified into epilepsy syndromes. Families were classified into syndromes where at least 2 family members had a specific diagnosis. Pedigrees were analyzed and molecular genetic studies were performed as appropriate. RESULTS: A total of 211 families were ascertained over an 11-year period in Israel. A total of 169 were classified into broad familial epilepsy syndrome groups: 61 generalized, 22 focal, 24 febrile seizure syndromes, 33 special syndromes, and 29 mixed. A total of 42 families remained unclassified. Pathogenic variants were identified in 49/211 families (23%). The majority were found in established epilepsy genes (e.g., SCN1A, KCNQ2, CSTB), but in 11 families, this cohort contributed to the initial discovery (e.g., KCNT1, PCDH19, TBC1D24). We expand the phenotypic spectrum of established epilepsy genes by reporting a familial LAMC3 homozygous variant, where the predominant phenotype was epilepsy with myoclonic-atonic seizures, and a pathogenic SCN1A variant in a family where in 5 siblings the phenotype was broadly consistent with Dravet syndrome, a disorder that usually occurs sporadically. CONCLUSION: A total of 80% of families were successfully classified, with pathogenic variants identified in 23%. The successful characterization of familial electroclinical and inheritance patterns has highlighted the value of studying multiplex families and their contribution towards uncovering the genetic basis of the epilepsies.
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Epilepsia/epidemiología , Epilepsia/genética , Familia , Predisposición Genética a la Enfermedad/epidemiología , Predisposición Genética a la Enfermedad/genética , Pruebas Genéticas/métodos , Estudios de Cohortes , Epilepsia/diagnóstico , Femenino , Humanos , Israel/epidemiología , Masculino , LinajeRESUMEN
PURPOSE: To present a unique case of a 65-year-old man using warfarin who presented with acute unilateral loss of vision due to hemorrhagic Descemet membrane detachment (DMD) with pupillary block and elevated intraocular pressure and its subsequent treatment and challenges. METHOD: Case report. RESULTS: Clinical examination showed a visual acuity of finger counting, central DMD with near contact to the iris and premembrane hemorrhage, an intraocular pressure (IOP) of 19 mmHg, and normal pupillary reaction. An International Normalized Ratio (INR) of 4.9 was treated with dose reduction and vitamin K. Twelve hours later the patient re-presented with an acute increase in pain and an IOP of 78 mmHg with pupillary block and iris bombé. YAG-laser membranotomy, anterior chamber paracentesis, and maximal topical and systemic therapy were unsuccessful in reducing the IOP. Surgical management, including irrigation and aspiration of blood, led to a normalization of the IOP. Descemet stripping automated endothelial keratoplasty (DSAEK) resulted in a visual acuity of 0.3. Deep stromal/pre-Descemet membrane neovascularization was found bilaterally, suspicious for a previous interstitial keratitis. CONCLUSIONS: The previously unreported complication of pupillary block following a pre-Descemet membrane hemorrhage was treated successfully for the first reported time, in a 2-step DSAEK. This indicates that DSAEK could be considered as a treatment option for DMD, especially in traumatic circumstances.
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Enfermedades de la Córnea/etiología , Lámina Limitante Posterior/patología , Hipema/etiología , Trastornos de la Pupila/etiología , Anciano , Enfermedades de la Córnea/diagnóstico , Enfermedades de la Córnea/cirugía , Neovascularización de la Córnea/diagnóstico , Neovascularización de la Córnea/etiología , Sustancia Propia/irrigación sanguínea , Queratoplastia Endotelial de la Lámina Limitante Posterior , Humanos , Hipema/diagnóstico , Hipema/cirugía , Relación Normalizada Internacional , Presión Intraocular , Terapia por Láser , Láseres de Estado Sólido/uso terapéutico , Masculino , Hipertensión Ocular/diagnóstico , Hipertensión Ocular/etiología , Trastornos de la Pupila/cirugía , Rotura Espontánea , Tomografía de Coherencia Óptica , Agudeza Visual/fisiología , Warfarina/administración & dosificaciónRESUMEN
Fragile X is a common cause of mental retardation in boys that can also affect girls. We present the case of a 21-year-old woman with Fragile X E (FRAXE) with learning difficulty, behavioural problems and epilepsy. Her diagnosis was made after investigations spanning several years, highlighting the importance of considering FRAXE and the benefits of reviewing genetic test results in the light of advancing technology.
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Síndrome del Cromosoma X Frágil/genética , Discapacidad Intelectual/genética , Proteínas de Unión al ARN , Southern Blotting , Metilación de ADN , Electroforesis en Gel de Poliacrilamida , Femenino , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil , Tamización de Portadores Genéticos , Humanos , Masculino , Repeticiones de Microsatélite , Proteínas del Tejido Nervioso/química , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Secuencias Repetitivas de Ácidos NucleicosRESUMEN
The primary aim of this article is to develop and defend a conceptual analysis of safety. The article begins by considering two previous analyses of safety in terms of risk acceptability. It is argued that these analyses fail because the notion of risk acceptability is more subjective than safety, as risk acceptability takes into account potential benefits in a way that safety does not. A distinction is then made between two different kinds of safety--safety qua cause and safety qua recipient--and both are defined in terms of the probability of a loss of value, though the relationship between safety and the probability of loss varies in each case. It is then shown that although this analysis is less subjective than the previously considered analyses, subjectivity can still enter into judgments of safety via the notions of probability and value. In the final section of this article, it is argued that the difference between safety and risk acceptability is important because it corresponds in significant ways to the difference between consequentialist and deontological moral viewpoints.
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Toma de Decisiones , Principios Morales , Medición de Riesgo , Seguridad , Femenino , Humanos , MasculinoRESUMEN
A retrospective cohort study of the 2002 Victorian prehospital emergency care documentation completed by ambulance paramedics had the objectives: (i) to design and implement a quality assessment tool to determine the quality of the ambulance patient care record (PCR)information; and (ii) to identify critical demographic and clinical items on the ambulance PCR that needed improvement. The study outcomes included a functioning quality assessment tool and associated user guide for prehospital use, and the identification of three critical PCR components requiring improvement. Ninety percent of PCRs passed the quality assessment; 10% (approximately 5 300) contained measurably poor or incomplete documentation.
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Ambulancias/normas , Auxiliares de Urgencia/normas , Gestión de la Información/normas , Registros Médicos/normas , Ambulancias/organización & administración , Benchmarking , Control de Formularios y Registros/normas , Investigación sobre Servicios de Salud , Humanos , Gestión de la Información/organización & administración , Evaluación de Programas y Proyectos de Salud/métodos , Control de Calidad , Estudios Retrospectivos , Triaje , VictoriaRESUMEN
Premutations of the fragile-X (FRAXA) gene were thought to have no clinical effects until recent reports of an increased incidence of premature ovarian failure in females and a late-onset neurological disorder in males. These patients were identified from families including typical fragile-X males with a full mutation. By analysing a cohort of patients with neurodegenerative disorders referred for genetic analysis of spinocerebellar ataxia genes, we have found that 3 of 59 males carry the premutation. Our patients extend the phenotype associated with the FRAXA premutation and indicate that it may account for a proportion of undiagnosed neurodegenerative disorders.
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Síndrome del Cromosoma X Frágil/genética , Mutación , Ataxias Espinocerebelosas/genética , Adulto , Anciano , Niño , Humanos , Masculino , Persona de Mediana Edad , Ataxias Espinocerebelosas/fisiopatología , Expansión de Repetición de TrinucleótidoRESUMEN
The CGG repeat in the 5' untranslated region of the fragile X mental retardation 1 gene (FMR1) exhibits remarkable instability upon transmission from mothers with premutation alleles. A collaboration of 13 laboratories in eight countries was established to examine four issues concerning FMR1 CGG-repeat instability among females with premutation (approximately 55-200 repeats) and intermediate (approximately 46-60 repeats) alleles. Our central findings were as follows: (1) The smallest premutation alleles that expanded to a full mutation (>200 repeats) in one generation contained 59 repeats; sequence analysis of the 59-repeat alleles from these two females revealed no AGG interruptions within the FMR1 CGG repeat. (2) When we corrected for ascertainment and recalculated the risks of expansion to a full mutation, we found that the risks for premutation alleles with <100 repeats were lower than those previously published. (3) When we examined the possible influence of sex of offspring on transmission of a full mutation-by analysis of 567 prenatal fragile X studies of 448 mothers with premutation and full-mutation alleles-we found no significant differences in the proportion of full-mutation alleles in male or female fetuses. (4) When we examined 136 transmissions of intermediate alleles from 92 mothers with no family history of fragile X, we found that, in contrast to the instability observed in families with fragile X, most (99/136 [72.8%]) transmissions of intermediate alleles were stable. The unstable transmissions (37/136 [27.2%]) in these families included both expansions and contractions in repeat size. The instability increased with the larger intermediate alleles (19% for 49-54 repeats, 30.9% for 55-59, and 80% for 60-65 repeats). These studies should allow improved risk assessments for genetic counseling of women with premutation or intermediate-size alleles.