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OBJECTIVES: Urinary tract infections (UTIs) frequently cause hospitalisation and death in people living with dementia (PLWD). We examine UTI incidence and associated mortality among PLWD relative to matched controls and people with diabetes and investigate whether delayed or withheld treatment further impacts mortality. METHODS: Data were extracted for n = 2,449,814 people aged ≥ 50 in Wales from 2000-2021, with groups matched by age, sex, and multimorbidity. Poisson regression was used to estimate incidences of UTI and mortality. Cox regression was used to study the effects of treatment timing. RESULTS: UTIs in dementia (HR=2.18, 95 %CI [1.88-2.53], p < .0) and diabetes (1.21[1.01-1.45], p = .035) were associated with high mortality, with the highest risk in individuals with diabetes and dementia (both) (2.83[2.40-3.34], p < .0) compared to matched individuals with neither dementia nor diabetes. 5.4 % of untreated PLWD died within 60 days of GP diagnosis-increasing to 5.9 % in PLWD with diabetes. CONCLUSIONS: Incidences of UTI and associated mortality are high in PLWD, especially in those with diabetes and dementia. Delayed treatment for UTI is further associated with high mortality.
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Demencia , Infecciones Urinarias , Humanos , Demencia/epidemiología , Demencia/complicaciones , Demencia/mortalidad , Infecciones Urinarias/epidemiología , Infecciones Urinarias/mortalidad , Infecciones Urinarias/complicaciones , Masculino , Femenino , Anciano , Incidencia , Persona de Mediana Edad , Anciano de 80 o más Años , Gales/epidemiología , Factores de Riesgo , Diabetes Mellitus/epidemiologíaRESUMEN
In multicellular organisms, cell types must be produced and maintained in appropriate proportions. One way this is achieved is through committed progenitor cells or extrinsic interactions that produce specific patterns of descendant cell types on lineage trees. However, cell fate commitment is probabilistic in most contexts, making it difficult to infer these dynamics and understand how they establish overall cell type proportions. Here, we introduce Lineage Motif Analysis (LMA), a method that recursively identifies statistically overrepresented patterns of cell fates on lineage trees as potential signatures of committed progenitor states or extrinsic interactions. Applying LMA to published datasets reveals spatial and temporal organization of cell fate commitment in zebrafish and rat retina and early mouse embryonic development. Comparative analysis of vertebrate species suggests that lineage motifs facilitate adaptive evolutionary variation of retinal cell type proportions. LMA thus provides insight into complex developmental processes by decomposing them into simpler underlying modules.
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Desarrollo Embrionario , Pez Cebra , Animales , Ratones , Ratas , Linaje de la Célula , Diferenciación Celular , Retina/metabolismo , Regulación del Desarrollo de la Expresión GénicaRESUMEN
Urinary Tract Infections (UTIs) are one of the most prevalent bacterial infections in older adults and a significant contributor to unplanned hospital admissions in People Living with Dementia (PLWD), with early detection being crucial due to the predicament of reporting symptoms and limited help-seeking behaviour. The most common diagnostic tool is urine sample analysis, which can be time-consuming and is only employed where UTI clinical suspicion exists. In this method development and proof-of-concept study, participants living with dementia were monitored via low-cost devices in the home that passively measure activity, sleep, and nocturnal physiology. Using 27828 person-days of remote monitoring data (from 117 participants), we engineered features representing symptoms used for diagnosing a UTI. We then evaluate explainable machine learning techniques in passively calculating UTI risk and perform stratification on scores to support clinical translation and allow control over the balance between alert rate and sensitivity and specificity. The proposed UTI algorithm achieves a sensitivity of 65.3% (95% Confidence Interval (CI) = 64.3-66.2) and specificity of 70.9% (68.6-73.1) when predicting UTIs on unseen participants and after risk stratification, a sensitivity of 74.7% (67.9-81.5) and specificity of 87.9% (85.0-90.9). In addition, feature importance methods reveal that the largest contributions to the predictions were bathroom visit statistics, night-time respiratory rate, and the number of previous UTI events, aligning with the literature. Our machine learning method alerts clinicians of UTI risk in subjects, enabling earlier detection and enhanced screening when considering treatment.
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In multicellular organisms, cell types must be produced and maintained in appropriate proportions. One way this is achieved is through committed progenitor cells that produce specific sets of descendant cell types. However, cell fate commitment is probabilistic in most contexts, making it difficult to infer progenitor states and understand how they establish overall cell type proportions. Here, we introduce Lineage Motif Analysis (LMA), a method that recursively identifies statistically overrepresented patterns of cell fates on lineage trees as potential signatures of committed progenitor states. Applying LMA to published datasets reveals spatial and temporal organization of cell fate commitment in zebrafish and rat retina and early mouse embryo development. Comparative analysis of vertebrate species suggests that lineage motifs facilitate adaptive evolutionary variation of retinal cell type proportions. LMA thus provides insight into complex developmental processes by decomposing them into simpler underlying modules.
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Bacterial symbioses allow annelids to colonise extreme ecological niches, such as hydrothermal vents and whale falls. Yet, the genetic principles sustaining these symbioses remain unclear. Here, we show that different genomic adaptations underpin the symbioses of phylogenetically related annelids with distinct nutritional strategies. Genome compaction and extensive gene losses distinguish the heterotrophic symbiosis of the bone-eating worm Osedax frankpressi from the chemoautotrophic symbiosis of deep-sea Vestimentifera. Osedax's endosymbionts complement many of the host's metabolic deficiencies, including the loss of pathways to recycle nitrogen and synthesise some amino acids. Osedax's endosymbionts possess the glyoxylate cycle, which could allow more efficient catabolism of bone-derived nutrients and the production of carbohydrates from fatty acids. Unlike in most Vestimentifera, innate immunity genes are reduced in O. frankpressi, which, however, has an expansion of matrix metalloproteases to digest collagen. Our study supports that distinct nutritional interactions influence host genome evolution differently in highly specialised symbioses.
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Anélidos , Poliquetos , Animales , Simbiosis/genética , Anélidos/genética , Poliquetos/genética , Poliquetos/metabolismo , Genoma/genética , Genómica , FilogeniaRESUMEN
Fosfomycin, originally named phosphonomycin when it was first isolated from fermentation broth of Streptomyces species and synthesized at Merck in 1969. The phosphonic acid containing a structurally strained and reactive epoxide ring confers broad spectrum, bactericidal activity against gram-positive and gram-negative bacteria. Fosfomycin's small size and hydrophilicity permits broad tissues penetration. Although only fosfomycin tromethamine oral is approved for urinary tract infections (UTI) in the United States since 1996, the intravenous form has been utilized worldwide for over four decades. The increasing rates of multidrug-resistant (MDR) infections with few novel treatment options available has spurred the recent interest in fosfomycin. Fosfomycin's high urinary concentration, broad spectrum of activity against MDR pathogens, and favorable safety profile offers a valuable oral option for treating UTI, one of the most common bacterial infections in childhood. The ability of fosfomycin to penetrate biofilm and reported activity against intracellular pathogens may further its importance in childhood diseases such as Chronic Granulomatous Disease, Salmonellosis, and Listeriosis. More data are needed to further define optimal Pharmacodynamic target, as well as Pharmacokinetic, safety and outcomes for repeated oral and intravenous dosing of fosfomycin in infants and children in systemic infections.
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Fosfomicina , Pediatría , Infecciones Urinarias , Niño , Humanos , Fosfomicina/farmacología , Fosfomicina/uso terapéutico , Antibacterianos/efectos adversos , Bacterias Gramnegativas , Bacterias Grampositivas , Infecciones Urinarias/tratamiento farmacológico , Infecciones Urinarias/microbiología , Pruebas de Sensibilidad MicrobianaRESUMEN
Indirect development with an intermediate larva exists in all major animal lineages1, which makes larvae central to most scenarios of animal evolution2-11. Yet how larvae evolved remains disputed. Here we show that temporal shifts (that is, heterochronies) in trunk formation underpin the diversification of larvae and bilaterian life cycles. We performed chromosome-scale genome sequencing in the annelid Owenia fusiformis with transcriptomic and epigenomic profiling during the life cycles of this and two other annelids. We found that trunk development is deferred to pre-metamorphic stages in the feeding larva of O. fusiformis but starts after gastrulation in the non-feeding larva with gradual metamorphosis of Capitella teleta and the direct developing embryo of Dimorphilus gyrociliatus. Accordingly, the embryos of O. fusiformis develop first into an enlarged anterior domain that forms larval tissues and the adult head12. Notably, this also occurs in the so-called 'head larvae' of other bilaterians13-17, with which the O. fusiformis larva shows extensive transcriptomic similarities. Together, our findings suggest that the temporal decoupling of head and trunk formation, as maximally observed in head larvae, facilitated larval evolution in Bilateria. This diverges from prevailing scenarios that propose either co-option9,10 or innovation11 of gene regulatory programmes to explain larva and adult origins.
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Genómica , Estadios del Ciclo de Vida , Poliquetos , Animales , Larva/anatomía & histología , Larva/crecimiento & desarrollo , Poliquetos/anatomía & histología , Poliquetos/embriología , Poliquetos/genética , Poliquetos/crecimiento & desarrollo , Perfilación de la Expresión Génica , Epigenómica , Cabeza/anatomía & histología , Cabeza/embriología , Cabeza/crecimiento & desarrolloRESUMEN
Embryonic stem (ES) cells can undergo many aspects of mammalian embryogenesis in vitro1-5, but their developmental potential is substantially extended by interactions with extraembryonic stem cells, including trophoblast stem (TS) cells, extraembryonic endoderm stem (XEN) cells and inducible XEN (iXEN) cells6-11. Here we assembled stem cell-derived embryos in vitro from mouse ES cells, TS cells and iXEN cells and showed that they recapitulate the development of whole natural mouse embryo in utero up to day 8.5 post-fertilization. Our embryo model displays headfolds with defined forebrain and midbrain regions and develops a beating heart-like structure, a trunk comprising a neural tube and somites, a tail bud containing neuromesodermal progenitors, a gut tube, and primordial germ cells. This complete embryo model develops within an extraembryonic yolk sac that initiates blood island development. Notably, we demonstrate that the neurulating embryo model assembled from Pax6-knockout ES cells aggregated with wild-type TS cells and iXEN cells recapitulates the ventral domain expansion of the neural tube that occurs in natural, ubiquitous Pax6-knockout embryos. Thus, these complete embryoids are a powerful in vitro model for dissecting the roles of diverse cell lineages and genes in development. Our results demonstrate the self-organization ability of ES cells and two types of extraembryonic stem cells to reconstitute mammalian development through and beyond gastrulation to neurulation and early organogenesis.
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Embrión de Mamíferos , Gastrulación , Modelos Biológicos , Neurulación , Organogénesis , Animales , Linaje de la Célula , Embrión de Mamíferos/citología , Embrión de Mamíferos/embriología , Células Madre Embrionarias/citología , Endodermo/citología , Endodermo/embriología , Corazón/embriología , Mesencéfalo/embriología , Ratones , Tubo Neural/embriología , Factor de Transcripción PAX6/deficiencia , Factor de Transcripción PAX6/genética , Prosencéfalo/embriología , Somitos/embriologíaRESUMEN
BACKGROUND: The 2020 consensus guidelines for vancomycin therapeutic monitoring recommend using Bayesian estimation targeting the ratio of the area under the curve over 24 hours to minimum inhibitory concentration as an optimal approach to individualize therapy in pediatric patients. To support institutional guideline implementation in children, the objective of this study was to comprehensively assess and compare published population-based pharmacokinetic (PK) vancomycin models and available Bayesian estimation tools, specific to neonatal and pediatric patients. METHODS: PubMed and Embase databases were searched from January 1994 to December 2020 for studies in which a vancomycin population PK model was developed to determine clearance and volume of distribution in neonatal and pediatric populations. Available Bayesian software programs were identified and assessed from published articles, software program websites, and direct communication with the software company. In the present review, 14 neonatal and 20 pediatric models were included. Six programs (Adult and Pediatric Kinetics, BestDose, DoseMeRx, InsightRx, MwPharm++, and PrecisePK) were evaluated. RESULTS: Among neonatal models, Frymoyer et al and Capparelli et al used the largest PK samples to generate their models, which were externally validated. Among the pediatric models, Le et al used the largest sample size, with multiple external validations. Of the Bayesian programs, DoseMeRx, InsightRx, and PrecisePK used clinically validated neonatal and pediatric models. CONCLUSIONS: To optimize vancomycin use in neonatal and pediatric patients, clinicians should focus on selecting a model that best fits their patient population and use Bayesian estimation tools for therapeutic area under the -curve-targeted dosing and monitoring.
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Programas Informáticos , Vancomicina , Adulto , Antibacterianos/farmacocinética , Área Bajo la Curva , Teorema de Bayes , Niño , Humanos , Recién Nacido , Cinética , Pruebas de Sensibilidad Microbiana , Vancomicina/farmacocinéticaRESUMEN
BACKGROUND: Imaging for low back pain is widely regarded as a target for efforts to reduce low-value care. OBJECTIVE: We aimed to estimate the prevalence of the overuse and underuse of lumbar imaging in patients presenting with low back pain to the emergency department (ED). METHODS: This was a retrospective chart review study of five public hospital EDs in Sydney, Australia, in 2019-20. We reviewed the clinical charts of consecutive adult patients who presented with a complaint of low back pain and extracted clinical features relevant to a decision to request lumbar imaging. We estimated the proportion of encounters where a decision to request lumbar imaging was inappropriate (overuse) or where a clinician did not request an appropriate and informative lumbar imaging test when indicated (underuse). RESULTS: Six hundred and forty-nine patients presented with a complaint of low back pain, of which 158 (24.3%) were referred for imaging. Seventy-nine (12.2%) had a combination of features suggesting that lumbar imaging was indicated according to clinical guidelines. The prevalence of overuse and underuse of lumbar imaging was 8.8% (57 of 649 cases, 95% CI 6.8-11.2%) and 4.3% (28 of 649 cases, 95% CI 3.0-6.1%), respectively. Thirteen cases were classified as underuse because the patients were referred for uninformative imaging modalities (e.g. referred for radiography for suspected cauda equina syndrome). CONCLUSION: In this study of emergency care, there was evidence of not only overuse of lumbar imaging but also underuse through failure to request lumbar imaging when indicated or referral for an uninformative imaging modality. These three issues seem more important targets for quality improvement than solely focusing on overuse.
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Dolor de la Región Lumbar , Adulto , Australia , Servicio de Urgencia en Hospital , Humanos , Dolor de la Región Lumbar/diagnóstico por imagen , Radiografía , Estudios RetrospectivosRESUMEN
OBJECTIVE: To evaluate the economic burden associated with therapeutic inertia in patients with type 2 diabetes mellitus (T2D) in Denmark. METHODS: The economic burden for a newly diagnosed Danish T2D population was estimated using a validated diabetes model (The Swedish Institute for Health Economics (IHE) Cohort model), based on achieving varying levels of glycemic control. The analyses were based on clinical data from the Danish Centre for Strategic Research (DD2) and supplemented with relevant Swedish data where variables were missing. The analysis estimated the economic burden for populations achieving different guideline-recommended targets for glycated hemoglobin (HbA1c) and for a number of therapeutic inertia scenarios. To estimate the population-level burden Danish specific epidemiology data were incorporated. All costs are reported in 2020 Danish kroner (DKK) and 2020 Euros (). RESULTS: The baseline HbA1c level used for this analysis was 7.9% (63 mmol/mol), which was observed in newly diagnosed Danish T2D patients prior to their first anti-diabetic treatment. Therapeutic inertia was associated with substantial economic burden compared to achieving immediate glycemic control (target < 6.5% (< 48 mmol/mol)). Per patient burdens were between 3562 DKK and 20,160 DKK (477- 2701) dependent on the duration of therapeutic inertia (1-7 years), with this further increased when indirect costs were included (9649 DKK to 51,585 DKK [1393-6912]). The economic burden at a population level was between 27 million DKK to 150 million DKK (3.6 million to 20 million), dependent on the duration of therapeutic inertia, rising to 72 million DKK to 384 million DKK (9.6 million to 51.4 million) when indirect costs were included. CONCLUSION: Achieving early and intensive glycemic control, thereby minimizing therapeutic inertia can lead to substantial savings for the Danish society, ranging between 72 million DKK and 384 million DKK (9.6 million to 51.4 million) (1-7 years of therapeutic inertia). This study highlights that efforts to minimize therapeutic inertia, by securing timely intensification before individual HbA1c targets are exceeded, results in significant long-term cost savings in Denmark.
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Diabetes Mellitus Tipo 2 , Costo de Enfermedad , Dinamarca/epidemiología , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/epidemiología , Hemoglobina Glucada/análisis , Control Glucémico , HumanosRESUMEN
Modern crises in implantable or indwelling blood-contacting medical devices are mainly due to the dual problems of infection and thrombogenicity. There is a paucity of biomaterials that can address both problems simultaneously through a singular platform. Taking cues from the body's own defense mechanism against infection and blood clotting (thrombosis) via the endogenous gasotransmitter nitric oxide (NO), both of these issues are addressed through the development of a layered S-nitroso-N-acetylpenicillamine (SNAP)-doped polymer with a blended selenium (Se)-polymer interface. The unique capability of the SNAP-Se-1 polymer composites to explicitly release NO from the SNAP reservoir as well as generate NO via the incorporated Se is reported for the first time. The NO release from the SNAP-doped polymer increased substantially in the presence of the Se interface. The Se interface was able to generate NO in the presence of S-nitrosoglutathione (GSNO) and glutathione (GSH), demonstrating the capability of generating NO from endogenous S-nitrosothiols (RSNO). Scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) traced distribution of elemental Se nanoparticles on the interface and the surface properties were evaluated by surface wettability and roughness. The SNAP-Se-1 efficiently inhibited the growth of bacteria and reduced platelet adhesion while showing minimal cytotoxicity, thus potentially eliminating the risks of systemic antibiotic and blood coagulation therapy. The SNAP-Se-1 exhibited antibacterial activity of â¼2.39 and â¼2.25 log reductions in the growth of clinically challenging adhered Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli. SNAP-Se-1 also significantly reduced platelet adhesion by 85.5% compared to corresponding controls. A WST-8-based cell viability test performed on NIH 3T3 mouse fibroblast cells provided supporting evidence for the potential biocompatibility of the material in vitro. These results highlight the prospective utility of SNAP-Se-1 as a blood-contacting infection-resistant biomaterial in vitro which can be further tuned by application specificity.
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Escherichia coli/crecimiento & desarrollo , Polímeros , S-Nitroso-N-Acetilpenicilamina , Selenio , Staphylococcus aureus/crecimiento & desarrollo , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Ratones , Células 3T3 NIH , Nanopartículas , Óxido Nítrico/farmacocinética , Óxido Nítrico/farmacología , Adhesividad Plaquetaria/efectos de los fármacos , Polímeros/química , Polímeros/farmacocinética , Polímeros/farmacología , S-Nitroso-N-Acetilpenicilamina/química , S-Nitroso-N-Acetilpenicilamina/farmacocinética , S-Nitroso-N-Acetilpenicilamina/farmacología , Selenio/química , Selenio/farmacocinética , Selenio/farmacología , PorcinosRESUMEN
We report that mRNA electroporation permits fluorescent proteins to label cells in living quail embryos more quickly and broadly than DNA electroporation. The high transfection efficiency permits at least 4 distinct mRNAs to be co-transfected with ~87% efficiency. Most of the electroporated mRNAs are degraded during the first 2 h post-electroporation, permitting time-sensitive experiments to be carried out in the developing embryo. Finally, we describe how to dynamically image live embryos electroporated with mRNAs that encode various subcellular targeted fluorescent proteins.
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Electroporación/métodos , Embrión no Mamífero/metabolismo , Proteínas Luminiscentes/genética , Codorniz/embriología , Animales , Expresión Génica , ARN Mensajero/genética , Factores de Tiempo , TransfecciónRESUMEN
Dynamin 2 (DNM2) is a GTP-binding protein that controls endocytic vesicle scission and defines a whole class of dynamin-dependent endocytosis, including clathrin-mediated endocytosis by caveoli. It has been suggested that mutations in the DNM2 gene, associated with 3 inherited diseases, disrupt endocytosis. However, how exactly mutations affect the nanoscale morphology of endocytic machinery has never been studied. In this paper, we used live correlative scanning ion conductance microscopy (SICM) and fluorescence confocal microscopy (FCM) to study how disease-associated mutations affect the morphology and kinetics of clathrin-coated pits (CCPs) by directly following their dynamics of formation, maturation, and internalization in skin fibroblasts from patients with centronuclear myopathy (CNM) and in Cos-7 cells expressing corresponding dynamin mutants. Using SICM-FCM, which we have developed, we show how p.R465W mutation disrupts pit structure, preventing its maturation and internalization, and significantly increases the lifetime of CCPs. Differently, p.R522H slows down the formation of CCPs without affecting their internalization. We also found that CNM mutations in DNM2 affect the distribution of caveoli and reduce dorsal ruffling in human skin fibroblasts. Collectively, our SICM-FCM findings at single CCP level, backed up by electron microscopy data, argue for the impairment of several forms of endocytosis in DNM2-linked CNM.-Ali, T., Bednarska, J., Vassilopoulos, S., Tran, M., Diakonov, I. A., Ziyadeh-Isleem, A., Guicheney, P., Gorelik, J., Korchev, Y. E., Reilly, M. M., Bitoun, M., Shevchuk, A. Correlative SICM-FCM reveals changes in morphology and kinetics of endocytic pits induced by disease-associated mutations in dynamin.
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Dinamina II/genética , Endocitosis/genética , Mutación/genética , Miopatías Estructurales Congénitas/genética , Adulto , Animales , Células COS , Línea Celular , Chlorocebus aethiops , Clatrina/genética , Femenino , Fibroblastos/patología , Humanos , Cinética , Masculino , Microscopía Confocal/métodos , Microscopía Electrónica de Rastreo/métodos , Microscopía Fluorescente/métodosRESUMEN
Background We previously showed, in patients with diabetes, that >50% of monitoring tests for glycated haemoglobin (HbA1c) are outside recommended intervals and that this is linked to diabetes control. Here, we examined the effect of tests/year on achievement of commonly utilised HbA1c targets and on HbA1c changes over time. Methods Data on 20,690 adults with diabetes with a baseline HbA1c of >53 mmol/mol (7%) were extracted from Clinical Biochemistry Laboratory records at three UK hospitals. We examined the effect of HbA1c tests/year on (i) the probability of achieving targets of ≤53 mmol/mol (7%) and ≤48 mmol/mol (6.5%) in a year using multi-state modelling and (ii) the changes in mean HbA1c using a linear mixed-effects model. Results The probabilities of achieving ≤53 mmol/mol (7%) and ≤48 mmol/mol (6.5%) targets within 1 year were 0.20 (95% confidence interval: 0.19-0.21) and 0.10 (0.09-0.10), respectively. Compared with four tests/year, having one test or more than four tests/year were associated with lower likelihoods of achieving either target; two to three tests/year gave similar likelihoods to four tests/year. Mean HbA1c levels were higher in patients who had one test/year compared to those with four tests/year (mean difference: 2.64 mmol/mol [0.24%], p<0.001). Conclusions We showed that ≥80% of patients with suboptimal control are not achieving commonly recommended HbA1c targets within 1 year, highlighting the major challenge facing healthcare services. We also demonstrated that, although appropriate monitoring frequency is important, testing every 6 months is as effective as quarterly testing, supporting international recommendations. We suggest that the importance HbA1c monitoring frequency is being insufficiently recognised in diabetes management.
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Diabetes Mellitus Tipo 2/sangre , Hemoglobina Glucada/análisis , Adulto , Glucemia/análisis , Femenino , Humanos , Masculino , ProbabilidadRESUMEN
Neural interfaces are designed to decode motor intent and evoke sensory precepts in amputees. In peripheral nerves, recording movement intent is challenging because motor axons are only a small fraction compared to sensory fibers and are heterogeneously mixed particularly at proximal levels. We previously reported that pain and myelinated axons regenerating through a Y-shaped nerve guide with sealed ends, can be modulated by luminar release of nerve growth factor (NGF) and neurotrophin-3 (NT-3), respectively. Here, we evaluate the differential potency of NGF, glial cell line-derived neurotrophic factor (GDNF), brain-derived neurotrophic factor (BDNF), pleiotrophin (PTN), and NT-3 in asymmetrically guiding the regeneration of sensory and motor neurons. We report that, in the absence of distal target organs, molecular guidance cues can mediate the growth of electrically conductive fascicles with normal microanatomy. Compared to Y-tube compartments with bovine serum albumin (BSA), GDNF and NGF increased the motor and sensory axon content, respectively. In addition, the sensory to motor ratio was significantly increased by PTN (12.7:1) when compared to a BDNF + GDNF choice. The differential content of motor and sensory axons modulated by selective guidance cues may provide a strategy to better define axon types in peripheral nerve interfaces.
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Amputación Quirúrgica , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Factor Neurotrófico Derivado de la Línea Celular Glial/metabolismo , Neuronas Motoras/fisiología , Regeneración Nerviosa , Nervios Periféricos/fisiología , Células Receptoras Sensoriales/fisiología , Animales , Proteínas Portadoras/metabolismo , Células Cultivadas , Señales (Psicología) , Citocinas/metabolismo , Potenciales Evocados Motores/efectos de los fármacos , Ratones , Factor de Crecimiento Nervioso/metabolismo , Neurotrofina 3/metabolismoRESUMEN
Mutations in structural maintenance of chromosomes (Smc) proteins are frequently associated with chromosomal abnormalities commonly observed in developmental disorders. However, the role of Smc proteins in development still remains elusive. To investigate Smc5/6 function during early embryogenesis we examined smc5 and smc6 mutants of the fruit fly Drosophila melanogaster using a combination of reverse genetics and microscopy approaches. Smc5/6 exhibited a maternally contributed function in maintaining chromosome stability during early embryo development, which manifested as female subfertility in its absence. Loss of Smc5/6 caused an arrest and a considerable delay in embryo development accompanied by fragmented nuclei and increased anaphase-bridge formation, respectively. Surprisingly, early embryonic arrest was attributable to the absence of Smc5/6 during oogenesis, which resulted in insufficient repair of pre-meiotic and meiotic DNA double-strand breaks. Thus, our findings contribute to the understanding of Smc proteins in higher eukaryotic development by highlighting a maternal function in chromosome maintenance and a link between oogenesis and early embryogenesis.
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OBJECTIVES: The contribution of individual immune response to Staphylococcus aureus bacteremia on outcome has not been well studied. The objective was to relate the host cytokine response to outcome of Staphylococcus aureus bacteremia. DESIGN: Prospective observational study. SETTING: Three U.S. university-affiliated medical centers. PATIENTS: Adult patients infected with Staphylococcus aureus bacteremia hospitalized between July 2012 and August 2014. INTERVENTIONS: Blood specimens were obtained at Staphylococcus aureus bacteremia onset and 72 hours after therapy initiation. Levels of tissue necrosis factor, interleukin-6, interleukin-8, interleukin-17A, and interleukin-10 were measured by enzyme-linked immunosorbent assay at each time point and compared between those with persistent bacteremia (≥ 4 d) and resolving bacteremia. Primary outcome was persistent bacteremia after 4 days of effective therapy. Secondary outcomes were 30-day mortality and 30-day recurrence. MEASUREMENTS AND MAIN RESULTS: A total of 196 patients were included (mean age, 59 yr); of them, 33% had methicillin-resistant Staphylococcus aureus bacteremia. Forty-seven percent of the methicillin-resistant Staphylococcus aureus strains were staphylococcal cassette chromosome mec IV. Persistent bacteremia occurred in 24% of patients (47/196); they were more likely to die than resolving bacteremia group (28% vs 5%; p < 0.001). Compared with resolving bacteremia group, persistent bacteremia patients had higher initial median levels of tissue necrosis factor (44.73 vs 21.68 pg/mL; p < 0.001), interleukin-8 (124.76 vs 47.48 pg/mL; p = 0.028), and interleukin-10 (104.31 vs 29.72 pg/mL; p < 0.001). Despite 72 hours of treatment, levels remained higher for the persistent bacteremia group than for the resolving bacteremia group (tissue necrosis factor: 26.95 vs 18.38 pg/mL, p = 0.02; interleukin-8: 70.75 vs 27.86 pg/mL, p = 0.002; interleukin-6: 67.50 vs 21.81 pg/mL, p = 0.005; and interleukin-10: 30.98 vs 12.60 pg/mL, p < 0.001). Interleukin-17A levels were similar between groups at both time points. After controlling for confounding variables by multivariate analysis, interleukin-10/tissue necrosis factor ratio at 72 hours most significantly predicted persistence (odds ratio, 2.98; 95% CI, 1.39-6.39; p = 0.005) and mortality (odds ratio, 9.87; 95% CI, 2.64-36.91; p < 0.001) at values more than 1.00 and more than 2.56, respectively. CONCLUSIONS: Sustained elevation of interleukin-10/tissue necrosis factor ratio at 72 hours suggests a dysregulated immune response and may be used to guide management to improve outcomes.
Asunto(s)
Antibacterianos/uso terapéutico , Bacteriemia/inmunología , Interleucinas/sangre , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Infecciones Estafilocócicas/mortalidad , Staphylococcus aureus/efectos de los fármacos , Factor de Necrosis Tumoral alfa/sangre , Adulto , Anciano , Bacteriemia/tratamiento farmacológico , Femenino , Humanos , Masculino , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Persona de Mediana Edad , Estudios Prospectivos , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/inmunología , Staphylococcus aureus/aislamiento & purificación , Resultado del Tratamiento , Estados UnidosRESUMEN
OBJECTIVE: We previously showed that in patients with diabetes mellitus, glycated hemoglobin (HbA1c) monitoring outside international guidance on testing frequency is widespread. Here we examined the relationship between testing frequency and diabetes control to test the hypothesis that retest interval is linked to change in HbA1c level. RESEARCH DESIGN AND METHODS: We examined repeat HbA1c tests (400,497 tests in 79,409 patients, 2008-2011) processed by three U.K. clinical laboratories. We examined the relationship between retest interval and 1) percentage change in HbA1c and 2) proportion of cases showing a significant HbA1c rise. The effect of demographics factors on these findings was also explored. RESULTS: Our data showed that the optimal testing frequency required to maximize the downward trajectory in HbA1c was four times per year, particularly in those with an initial HbA1c of ≥7% (≥53 mmol/mol), supporting international guidance. Testing 3-monthly was associated with a 3.8% reduction in HbA1c compared with a 1.5% increase observed with annual testing; testing more frequently provided no additional benefit. Compared with annual monitoring, 3-monthly testing was associated with a halving of the proportion showing a significant rise in HbA1c (7-10 vs. 15-20%). CONCLUSIONS: These findings provide, in a large, multicenter data set, objective evidence that testing outside guidance on HbA1c monitoring frequency is associated with a significant detrimental effect on diabetes control. To achieve the optimum downward trajectory in HbA1c, monitoring frequency should be quarterly, particularly in cases with suboptimal HbA1c. While this impact appears small, optimizing monitoring frequency across the diabetes population may have major implications for diabetes control and comorbidity risk.
Asunto(s)
Diabetes Mellitus/sangre , Diabetes Mellitus/tratamiento farmacológico , Hemoglobina Glucada/análisis , Cooperación del Paciente/estadística & datos numéricos , Anciano , Automonitorización de la Glucosa Sanguínea/estadística & datos numéricos , Comorbilidad , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Monitoreo FisiológicoRESUMEN
A subset of medulloblastomas, the most common brain tumor in children, is hypothesized to originate from granule neuron precursors (GNPs) in which the sonic hedgehog (SHH) pathway is over-activated. MXD3, a basic helix-look-helix zipper transcription factor of the MAD family, has been reported to be upregulated during postnatal cerebellar development and to promote GNP proliferation and MYCN expression. Mxd3 is upregulated in mouse models of medulloblastoma as well as in human medulloblastomas. Therefore, we hypothesize that MXD3 plays a role in the cellular events that lead to medulloblastoma biogenesis. In agreement with its proliferative role in GNPs, MXD3 knock-down in DAOY cells resulted in decreased proliferation. Sustained overexpression of MXD3 resulted in decreased cell numbers due to increased apoptosis and cell cycle arrest. Structure-function analysis revealed that the Sin3 interacting domain, the basic domain, and binding to E-boxes are essential for this activity. Microarray-based expression analysis indicated up-regulation of 84 genes and down-regulation of 47 genes. Potential direct MXD3 target genes were identified by ChIP-chip. Our results suggest that MXD3 is necessary for DAOY medulloblastoma cell proliferation. However, increased level and/or duration of MXD3 expression ultimately reduces cell numbers via increased cell death and cell cycle arrest.