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1.
Psychol Med ; 53(12): 5428-5441, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-35879886

RESUMEN

BACKGROUND: The impact of the coronavirus disease 2019 (COVID-19) pandemic on mental health is still being unravelled. It is important to identify which individuals are at greatest risk of worsening symptoms. This study aimed to examine changes in depression, anxiety and post-traumatic stress disorder (PTSD) symptoms using prospective and retrospective symptom change assessments, and to find and examine the effect of key risk factors. METHOD: Online questionnaires were administered to 34 465 individuals (aged 16 years or above) in April/May 2020 in the UK, recruited from existing cohorts or via social media. Around one-third (n = 12 718) of included participants had prior diagnoses of depression or anxiety and had completed pre-pandemic mental health assessments (between September 2018 and February 2020), allowing prospective investigation of symptom change. RESULTS: Prospective symptom analyses showed small decreases in depression (PHQ-9: -0.43 points) and anxiety [generalised anxiety disorder scale - 7 items (GAD)-7: -0.33 points] and increases in PTSD (PCL-6: 0.22 points). Conversely, retrospective symptom analyses demonstrated significant large increases (PHQ-9: 2.40; GAD-7 = 1.97), with 55% reported worsening mental health since the beginning of the pandemic on a global change rating. Across both prospective and retrospective measures of symptom change, worsening depression, anxiety and PTSD symptoms were associated with prior mental health diagnoses, female gender, young age and unemployed/student status. CONCLUSIONS: We highlight the effect of prior mental health diagnoses on worsening mental health during the pandemic and confirm previously reported sociodemographic risk factors. Discrepancies between prospective and retrospective measures of changes in mental health may be related to recall bias-related underestimation of prior symptom severity.


Asunto(s)
COVID-19 , Trastornos por Estrés Postraumático , Femenino , Humanos , Trastornos por Estrés Postraumático/epidemiología , Trastornos por Estrés Postraumático/psicología , COVID-19/epidemiología , Pandemias , Depresión/psicología , Estudios Retrospectivos , Estudios Prospectivos , SARS-CoV-2 , Ansiedad/psicología , Reino Unido/epidemiología
2.
Psychol Med ; 50(3): 446-455, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-30773149

RESUMEN

BACKGROUND: Functional neurological disorder (FND), previously known as conversion disorder, is common and often results in substantial distress and disability. Previous research lacks large sample sizes and clinical surveys are most commonly derived from neurological settings, limiting our understanding of the disorder and its associations in other contexts. We sought to address this by analysing a large anonymised electronic psychiatric health record dataset. METHODS: Data were obtained from 322 patients in the South London and Maudsley NHS Foundation Trust (SLaM) who had an ICD-10 diagnosis of motor FND (mFND) (limb weakness or disorders of movement or gait) between 1 January 2006 and 31 December 2016. Data were collected on a range of socio-demographic and clinical factors and compared to 644 psychiatric control patients from the same register. RESULTS: Weakness was the most commonly occurring functional symptom. mFND patients were more likely to be female, British, married, employed pre-morbidly, to have a carer and a physical health condition, but less likely to have had an inpatient psychiatric admission or to receive benefits. No differences in self-reported sexual or physical abuse rates were observed between groups, although mFND patients were more likely to experience life events linked to inter-personal difficulties. CONCLUSIONS: mFND patients have distinct demographic characteristics compared with psychiatric controls. Experiences of abuse appear to be equally prevalent across psychiatric patient groups. This study establishes the socio-demographic and life experience profile of this understudied patient group and may be used to guide future therapeutic interventions designed specifically for mFND.


Asunto(s)
Trastornos de Conversión/epidemiología , Trastornos Motores/epidemiología , Enfermedades del Sistema Nervioso/epidemiología , Adulto , Estudios de Casos y Controles , Trastornos de Conversión/psicología , Femenino , Hospitalización , Humanos , Acontecimientos que Cambian la Vida , Modelos Logísticos , Masculino , Servicios de Salud Mental/estadística & datos numéricos , Persona de Mediana Edad , Trastornos Motores/psicología , Enfermedades del Sistema Nervioso/psicología , Reino Unido
3.
Eur J Neurol ; 27(7): 1336-1342, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32073712

RESUMEN

BACKGROUND AND PURPOSE: Cauda equina syndrome (CES) is a neurosurgical emergency which warrants lumbar magnetic resonance imaging (MRI). Many patients with suggestive symptoms of CES have no radiological correlate. A functional (non-organic) aetiology has been proposed in some, but currently little is known about this patient group and their clinical outcomes. METHODS: At a tertiary referral centre, 155 adult patients underwent urgent lumbar MRI for suspected CES in 1 year from December 2014. Data regarding clinical symptoms and follow-up were obtained from records. Patients were divided into CES (n = 25), radiculopathy (n = 68) and scan-negative (SN) groups (n = 62) from scans. Up to 3 years post-discharge, postal questionnaires were sent to patients with Oswestry Disability Index, Pain Catastrophizing score, Patient Health Questionnaire (PHQ) 9, Generalized Anxiety Disorder (GAD) 7, PHQ 15 and Work and Social Adjustment Scale measures. RESULTS: No clinical symptoms were found to differentiate CES from SN patients. Functional comorbidities were significantly more common in SN patients but mental health diagnosis frequency did not differ. Follow-up was variable with no consistent referral pathways, particularly for the SN group. 33% (n = 47) responded to the postal questionnaires; high levels of pain, symptom chronicity and disability were ubiquitous but self-reported mental health diagnoses and PHQ 15 were higher for SN patients. CONCLUSIONS: Conflicting data suggest further research is needed to investigate the prevalence of mental illness and somatic symptoms in SN cases. SN patients have higher rates of comorbid functional disorders and inconsistent referral pathways. Self-report measures indicate impaired quality of life across all groups. The low response rate limits the generalizability of findings but neuropsychiatric assessment and care pathway optimization should be considered.


Asunto(s)
Síndrome de Cauda Equina , Cuidados Posteriores , Humanos , Imagen por Resonancia Magnética , Alta del Paciente , Proyectos Piloto , Calidad de Vida , Estudios Retrospectivos
4.
Nature ; 506(7486): 71-5, 2014 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-24463513

RESUMEN

Progress in atomic, optical and quantum science has led to rapid improvements in atomic clocks. At the same time, atomic clock research has helped to advance the frontiers of science, affecting both fundamental and applied research. The ability to control quantum states of individual atoms and photons is central to quantum information science and precision measurement, and optical clocks based on single ions have achieved the lowest systematic uncertainty of any frequency standard. Although many-atom lattice clocks have shown advantages in measurement precision over trapped-ion clocks, their accuracy has remained 16 times worse. Here we demonstrate a many-atom system that achieves an accuracy of 6.4 × 10(-18), which is not only better than a single-ion-based clock, but also reduces the required measurement time by two orders of magnitude. By systematically evaluating all known sources of uncertainty, including in situ monitoring of the blackbody radiation environment, we improve the accuracy of optical lattice clocks by a factor of 22. This single clock has simultaneously achieved the best known performance in the key characteristics necessary for consideration as a primary standard-stability and accuracy. More stable and accurate atomic clocks will benefit a wide range of fields, such as the realization and distribution of SI units, the search for time variation of fundamental constants, clock-based geodesy and other precision tests of the fundamental laws of nature. This work also connects to the development of quantum sensors and many-body quantum state engineering (such as spin squeezing) to advance measurement precision beyond the standard quantum limit.

5.
Dysphagia ; 35(2): 242-252, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31115661

RESUMEN

Recent studies show that understanding the rheological properties of thickened fluids, such as viscosity and yield stress, is advantageous in designing optimal thickened fluids for the treatment of dysphagia. To date, these studies have focused on the rheological behavior of thickened fluids in shear deformation, while limited information is available on the surface tension of thickened fluids or their rheological behavior in extensional deformation. Knowledge of the extensional properties of thickened fluids (extensional viscosity and cohesiveness) is important to fully understand the behavior of such fluids while swallowing. Our aim in this work, therefore, was to characterize water and skim milk thickened with a commercial thickener (xanthan gum based) to determine extensional deformation and surface tension properties. It was observed that the surface tension decreases as the thickener concentration increases due to the accumulation of the biopolymer at the surface of the fluid when it dissolves in water. In addition, the extensional viscosity of the fluid increased over time as the filament thinned (i.e., as the Hencky strain increased) until it reached a plateau. It was observed that the maximum extensional viscosity, which is related to the cohesiveness of the fluid, increases with the higher concentrations of thickener. However, the cohesiveness of thickened skim milk was lower than that of the thickened water at a given thickener concentration due to lower surface tension. This study confirms that by increasing the concentration of thickener, it will not only increase the shear viscosity (i.e., bolus thickness) of the fluid, but also the extensional viscosity (i.e., bolus cohesiveness).


Asunto(s)
Aditivos Alimentarios/farmacología , Leche/química , Reología/métodos , Tensión Superficial/efectos de los fármacos , Viscosidad/efectos de los fármacos , Agua/química , Animales , Deglución , Trastornos de Deglución , Humanos , Polisacáridos Bacterianos/farmacología
6.
BMC Bioinformatics ; 19(Suppl 18): 491, 2018 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-30577736

RESUMEN

BACKGROUND: Current multi-petaflop supercomputers are powerful systems, but present challenges when faced with problems requiring large machine learning workflows. Complex algorithms running at system scale, often with different patterns that require disparate software packages and complex data flows cause difficulties in assembling and managing large experiments on these machines. RESULTS: This paper presents a workflow system that makes progress on scaling machine learning ensembles, specifically in this first release, ensembles of deep neural networks that address problems in cancer research across the atomistic, molecular and population scales. The initial release of the application framework that we call CANDLE/Supervisor addresses the problem of hyper-parameter exploration of deep neural networks. CONCLUSIONS: Initial results demonstrating CANDLE on DOE systems at ORNL, ANL and NERSC (Titan, Theta and Cori, respectively) demonstrate both scaling and multi-platform execution.


Asunto(s)
Detección Precoz del Cáncer/métodos , Aprendizaje Automático/tendencias , Neoplasias/diagnóstico , Humanos , Neoplasias/patología , Redes Neurales de la Computación , Flujo de Trabajo
8.
Psychol Med ; 46(12): 2617-26, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27377290

RESUMEN

BACKGROUND: Psychological models of conversion disorder (CD) traditionally assume that psychosocial stressors are identifiable around symptom onset. In the face of limited supportive evidence such models are being challenged. METHOD: Forty-three motor CD patients, 28 depression patients and 28 healthy controls were assessed using the Life Events and Difficulties Schedule in the year before symptom onset. A novel 'escape' rating for events was developed to test the Freudian theory that physical symptoms of CD could provide escape from stressors, a form of 'secondary gain'. RESULTS: CD patients had significantly more severe life events and 'escape' events than controls. In the month before symptom onset at least one severe event was identified in 56% of CD patients - significantly more than 21% of depression patients [odds ratio (OR) 4.63, 95% confidence interval (CI) 1.56-13.70] and healthy controls (OR 5.81, 95% CI 1.86-18.2). In the same time period 53% of CD patients had at least one 'high escape' event - again significantly higher than 14% in depression patients (OR 6.90, 95% CI 2.05-23.6) and 0% in healthy controls. Previous sexual abuse was more commonly reported in CD than controls, and in one third of female patients was contextually relevant to life events at symptom onset. The majority (88%) of life events of potential aetiological relevance were not identified by routine clinical assessments. Nine per cent of CD patients had no identifiable severe life events. CONCLUSIONS: Evidence was found supporting the psychological model of CD, the Freudian notion of escape and the potential aetiological relevance of childhood traumas in some patients. Uncovering stressors of potential aetiological relevance requires thorough psychosocial evaluation.


Asunto(s)
Adultos Sobrevivientes de Eventos Adversos Infantiles/psicología , Trastornos de Conversión/psicología , Acontecimientos que Cambian la Vida , Delitos Sexuales/psicología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad
9.
Genes Immun ; 16(2): 162-9, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25569264

RESUMEN

This work examines the role the lysine methyltransferase KMT1E (Setdb1) in thymocyte development. We have developed and described a T cell-specific conditional knockout of Setdb1. A partial block was seen at the double-positive to single-positive transition, causing reduced numbers of single-positive T cells in the thymus and periphery. Knockout thymocytes had reduced numbers of CD69(+) and T-cell receptor TCRß(+) cells and increased numbers of apoptotic cells in the double-positive compartment, suggesting an alteration in the selection process. Transcriptional profiling of thymocytes revealed that Setdb1 deletion derepresses expression of FcγRIIb, the inhibitory Fc receptor. We demonstrate that a KMT1E-containing complex directly interacts with the FcγRIIb promoter and that histone H3 at lysine 9 tri-methylation at this promoter is dependent on Setdb1 expression. Derepression of FcγRIIb causes exacerbated signaling through the TCR complex, with specifically increased phosphorylation of ZAP70, affecting selection. This work identifies KMT1E as a novel repressor of FcγRIIb and identifies an underappreciated role of FcγRIIb in fine tuning thymocyte development.


Asunto(s)
Cromatina/metabolismo , N-Metiltransferasa de Histona-Lisina/fisiología , Receptores de IgG/genética , Timocitos/fisiología , Animales , Metilación de ADN , Perfilación de la Expresión Génica , N-Metiltransferasa de Histona-Lisina/genética , Ratones , Ratones Noqueados , Regiones Promotoras Genéticas , Receptores de Antígenos de Linfocitos T/metabolismo , Transducción de Señal , Linfocitos T/citología , Linfocitos T/metabolismo , Linfocitos T/fisiología , Timocitos/citología , Timocitos/metabolismo
10.
J Neurol Neurosurg Psychiatry ; 85(2): 227-9, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24039028

RESUMEN

OBJECTIVE: To investigate potential abnormalities in subcortical brain structures in conversion disorder (CD) compared with controls using a region of interest (ROI) approach. METHODS: Fourteen patients with motor CD were compared with 31 healthy controls using high-resolution MRI scans with an ROI approach focusing on the basal ganglia, thalamus and amygdala. Brain volumes were measured using Freesurfer, a validated segmentation algorithm. RESULTS: Significantly smaller left thalamic volumes were found in patients compared with controls when corrected for intracranial volume. These reductions did not vary with handedness, laterality, duration or severity of symptoms. CONCLUSIONS: These differences may reflect a primary disease process in this area or be secondary effects of the disorder, for example, resulting from limb disuse. Larger, longitudinal structural imaging studies will be required to confirm the findings and explore whether they are primary or secondary to CD.


Asunto(s)
Trastornos de Conversión/patología , Neuroimagen , Tálamo/patología , Adulto , Amígdala del Cerebelo/patología , Atrofia/patología , Ganglios Basales/patología , Estudios de Casos y Controles , Femenino , Humanos , Masculino
11.
Psychol Med ; 44(12): 2475-87, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24330811

RESUMEN

BACKGROUND: Anti-N-methyl-D-aspartate (NMDA) receptor encephalitis is an autoimmune condition caused by immunoglobulin (Ig)G antibodies directed against the NR1 subunit of the NMDA glutamate receptor. Approximately 65% of cases present with psychiatric symptoms, particularly psychosis. It remains to be established whether anti-NMDA receptor antibodies can cause a 'purely' psychotic illness without overt neurological symptoms. METHOD: We conducted a systematic literature search to establish what proportion of patients with schizophrenia and related psychoses have antibodies directed against the NMDA receptor. Studies were included if (a) subjects had a diagnosis of schizophrenia, schizophrenia spectrum disorder or first-episode psychosis (FEP) using standard criteria, (b) serum was analysed for the presence of anti-NMDA receptor antibodies; and (c) the purpose of the study was to look for the presence of anti-NMDA receptor antibodies in patients with a primary psychiatric diagnosis without clinical signs of encephalitis. RESULTS: Seven studies were included, comprising 1441 patients, of whom 115 [7.98%, 95% confidence interval (CI) 6.69-9.50] were anti-NMDA receptor antibody positive. Of these, 21 (1.46%, 95% CI 0.94-2.23) patients were positive for antibodies of the IgG subclass. Prevalence rates were greater in cases than controls only for IgG antibodies; other subclasses are of less certain aetiological relevance. There was significant heterogeneity in terms of patient characteristics and the antibody assay used. CONCLUSIONS: A minority of patients with psychosis are anti-NMDA receptor antibody positive. It remains to be established whether this subset of patients differs from antibody-negative patients in terms of underlying pathology and response to antipsychotic treatment, and whether immunomodulatory treatments are effective in alleviating psychotic symptoms in this group.


Asunto(s)
Autoanticuerpos/inmunología , Trastornos Psicóticos/inmunología , Receptores de N-Metil-D-Aspartato/inmunología , Esquizofrenia/inmunología , Humanos
12.
Epilepsy Behav ; 36: 33-8, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24840753

RESUMEN

Postictal psychosis (PIP) is a serious psychiatric complication of epilepsy that occurs in approximately 6% of patients following multiple complex partial or generalized seizures. The psychosis is classically described as having a pleomorphic phenomenology, including paranoid, grandiose, and religious delusions as well as multimodal hallucinations with prominent affective changes and agitation. Little is understood about the pathophysiology of the condition. There has been a recent increase in interest in the relevance of autoimmunity to the pathogenesis of both epilepsy and psychosis. Studies have demonstrated the presence of antibodies directed against synaptic autoantigens (such as the N-methyl-d-aspartate receptor or the voltage-gated potassium channel complex) in approximately 10% of cases of sporadic epilepsy. These same autoantibodies are known to cause encephalopathy syndromes which feature psychiatric symptoms, usually psychosis, as a prominent part of the phenotype as well as other neurological features such as seizures, movement disorders, and autonomic dysfunction. It is beginning to be asked if these antibodies can be associated with a purely psychiatric phenotype. Here, we hypothesize that PIP may be an autoimmune phenomenon mediated by autoantibodies against synaptic antigens. More specifically, we outline a potential mechanism whereby long or repeated seizures cause short-lived blood-brain barrier (BBB) dysfunction during which the brain becomes exposed to pathogenic autoantibodies. In essence, we propose that PIP is a time-limited, seizure-dependent, autoantibody-mediated encephalopathy syndrome. We highlight a number of features of PIP that may be explained by this mechanism, such as the lucid interval between seizures and onset of psychosis and the progression in some cases to a chronic, interictal psychosis.


Asunto(s)
Autoinmunidad , Epilepsia/complicaciones , Epilepsia/inmunología , Trastornos Psicóticos/etiología , Animales , Epilepsia/psicología , Humanos
13.
J Neurol Sci ; 449: 120646, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-37100018

RESUMEN

INTRODUCTION: Uniform case definitions are required to ensure harmonised reporting of neurological syndromes associated with SARS-CoV-2. Moreover, it is unclear how clinicians perceive the relative importance of SARS-CoV-2 in neurological syndromes, which risks under- or over-reporting. METHODS: We invited clinicians through global networks, including the World Federation of Neurology, to assess ten anonymised vignettes of SARS-CoV-2 neurological syndromes. Using standardised case definitions, clinicians assigned a diagnosis and ranked association with SARS-CoV-2. We compared diagnostic accuracy and assigned association ranks between different settings and specialties and calculated inter-rater agreement for case definitions as "poor" (κ ≤ 0.4), "moderate" or "good" (κ > 0.6). RESULTS: 1265 diagnoses were assigned by 146 participants from 45 countries on six continents. The highest correct proportion were cerebral venous sinus thrombosis (CVST, 95.8%), Guillain-Barré syndrome (GBS, 92.4%) and headache (91.6%) and the lowest encephalitis (72.8%), psychosis (53.8%) and encephalopathy (43.2%). Diagnostic accuracy was similar between neurologists and non-neurologists (median score 8 vs. 7/10, p = 0.1). Good inter-rater agreement was observed for five diagnoses: cranial neuropathy, headache, myelitis, CVST, and GBS and poor agreement for encephalopathy. In 13% of vignettes, clinicians incorrectly assigned lowest association ranks, regardless of setting and specialty. CONCLUSION: The case definitions can help with reporting of neurological complications of SARS-CoV-2, also in settings with few neurologists. However, encephalopathy, encephalitis, and psychosis were often misdiagnosed, and clinicians underestimated the association with SARS-CoV-2. Future work should refine the case definitions and provide training if global reporting of neurological syndromes associated with SARS-CoV-2 is to be robust.


Asunto(s)
COVID-19 , Encefalitis , Síndrome de Guillain-Barré , Enfermedades del Sistema Nervioso , Humanos , COVID-19/complicaciones , COVID-19/diagnóstico , SARS-CoV-2 , Variaciones Dependientes del Observador , Incertidumbre , Enfermedades del Sistema Nervioso/etiología , Enfermedades del Sistema Nervioso/complicaciones , Encefalitis/complicaciones , Cefalea/diagnóstico , Cefalea/etiología , Síndrome de Guillain-Barré/diagnóstico , Síndrome de Guillain-Barré/complicaciones , Prueba de COVID-19
14.
Phys Rev Lett ; 109(23): 230801, 2012 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-23368177

RESUMEN

Many-particle optical lattice clocks have the potential for unprecedented measurement precision and stability due to their low quantum projection noise. However, this potential has so far never been realized because clock stability has been limited by frequency noise of optical local oscillators. By synchronously probing two ^{87}Sr lattice systems using a laser with a thermal noise floor of 1×10(-15), we remove classically correlated laser noise from the intercomparison, but this does not demonstrate independent clock performance. With an improved optical oscillator that has a 1×10(-16) thermal noise floor, we demonstrate an order of magnitude improvement over the best reported stability of any independent clock, achieving a fractional instability of 1×10(-17) in 1000 s of averaging time for synchronous or asynchronous comparisons. This result is within a factor of 2 of the combined quantum projection noise limit for a 160 ms probe time with ~10(3) atoms in each clock. We further demonstrate that even at this high precision, the overall systematic uncertainty of our clock is not limited by atomic interactions. For the second Sr clock, which has a cavity-enhanced lattice, the atomic-density-dependent frequency shift is evaluated to be -3.11×10(-17) with an uncertainty of 8.2×10(-19).

15.
PLoS One ; 17(3): e0264983, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35271634

RESUMEN

Hepatitis C virus (HCV) infection is a leading cause of chronic liver disease and mortality worldwide. Direct-acting antiviral (DAA) therapy leads to high cure rates. However, persons who inject drugs (PWID) are at risk for reinfection after cure and may require multiple DAA treatments to reach the World Health Organization's (WHO) goal of HCV elimination by 2030. Using an agent-based model (ABM) that accounts for the complex interplay of demographic factors, risk behaviors, social networks, and geographic location for HCV transmission among PWID, we examined the combination(s) of DAA enrollment (2.5%, 5%, 7.5%, 10%), adherence (60%, 70%, 80%, 90%) and frequency of DAA treatment courses needed to achieve the WHO's goal of reducing incident chronic infections by 90% by 2030 among a large population of PWID from Chicago, IL and surrounding suburbs. We also estimated the economic DAA costs associated with each scenario. Our results indicate that a DAA treatment rate of >7.5% per year with 90% adherence results in 75% of enrolled PWID requiring only a single DAA course; however 19% would require 2 courses, 5%, 3 courses and <2%, 4 courses, with an overall DAA cost of $325 million to achieve the WHO goal in metropolitan Chicago. We estimate a 28% increase in the overall DAA cost under low adherence (70%) compared to high adherence (90%). Our modeling results have important public health implications for HCV elimination among U.S. PWID. Using a range of feasible treatment enrollment and adherence rates, we report robust findings supporting the need to address re-exposure and reinfection among PWID to reduce HCV incidence.


Asunto(s)
Consumidores de Drogas , Hepatitis C Crónica , Hepatitis C , Abuso de Sustancias por Vía Intravenosa , Antivirales/uso terapéutico , Chicago/epidemiología , Hepacivirus , Hepatitis C/complicaciones , Hepatitis C/tratamiento farmacológico , Hepatitis C/epidemiología , Hepatitis C Crónica/tratamiento farmacológico , Humanos , Reinfección , Abuso de Sustancias por Vía Intravenosa/complicaciones , Abuso de Sustancias por Vía Intravenosa/tratamiento farmacológico , Abuso de Sustancias por Vía Intravenosa/epidemiología
16.
Phys Rev Lett ; 107(7): 073202, 2011 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-21902391

RESUMEN

Using a narrow intercombination line in alkaline earth atoms to mitigate large inelastic losses, we explore the optical Feshbach resonance effect in an ultracold gas of bosonic (88)Sr. A systematic measurement of three resonances allows precise determinations of the optical Feshbach resonance strength and scaling law, in agreement with coupled-channel theory. Resonant enhancement of the complex scattering length leads to thermalization mediated by elastic and inelastic collisions in an otherwise ideal gas. Optical Feshbach resonance could be used to control atomic interactions with high spatial and temporal resolution.

17.
Inorganica Chim Acta ; 373(1): 301-305, 2011 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-21836726

RESUMEN

The reaction of the Tc(II) nitrosyl complex (Bu(4)N)[Tc(NO)Cl(4)] with Di-(2-picolyl)(NEt)amine in methanol yields the neutral complex [Tc(NO)Cl(py-N(Et)-py)]. The reaction of the Tc(I) nitrosyl complex [Tc(NO)Cl(2)(HOMe)(PPh(3))(2)] with this tridentate ligand yields cationic [Tc(NO)Cl(py-N(Et)-py)(PPh(3))]Cl. These two complexes have been structurally characterized. The reaction of [Tc(NO)Cl(2)(HOMe)(PPh(3))(2)] with the tetradentate ligand 1,4-Bis(2-pyridylmethyl)-1,4-diazobutane yields a mixture of products including cationic [Tc(NO)Cl(py-NH-NH-py)]Cl and cationic [Tc(NO)Cl(PPh(3))(py-NH-NH~py)]Cl, with a pyridyl terminus left dangling.

18.
Front Physiol ; 12: 718276, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35153804

RESUMEN

BACKGROUND: Fecal immunochemical testing (FIT) is an established method for colorectal cancer (CRC) screening. Measured FIT-concentrations are associated with both present and future risk of CRC, and may be used for personalized screening. However, evaluation of personalized screening is computationally challenging. In this study, a broadly applicable algorithm is presented to efficiently optimize personalized screening policies that prescribe screening intervals and FIT-cutoffs, based on age and FIT-history. METHODS: We present a mathematical framework for personalized screening policies and a bi-objective evolutionary algorithm that identifies policies with minimal costs and maximal health benefits. The algorithm is combined with an established microsimulation model (MISCAN-Colon), to accurately estimate the costs and benefits of generated policies, without restrictive Markov assumptions. The performance of the algorithm is demonstrated in three experiments. RESULTS: In Experiment 1, a relatively small benchmark problem, the optimal policies were known. The algorithm approached the maximum feasible benefits with a relative difference of 0.007%. Experiment 2 optimized both intervals and cutoffs, Experiment 3 optimized cutoffs only. Optimal policies in both experiments are unknown. Compared to policies recently evaluated for the USPSTF, personalized screening increased health benefits up to 14 and 4.3%, for Experiments 2 and 3, respectively, without adding costs. Generated policies have several features concordant with current screening recommendations. DISCUSSION: The method presented in this paper is flexible and capable of optimizing personalized screening policies evaluated with computationally-intensive but established simulation models. It can be used to inform screening policies for CRC or other diseases. For CRC, more debate is needed on what features a policy needs to exhibit to make it suitable for implementation in practice.

19.
Sarcoidosis Vasc Diffuse Lung Dis ; 27(2): 111-20, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21319593

RESUMEN

BACKGROUND: Sarcoidosis is a common multisystem disease of unknown cause and Ireland is among the countries with the highest reported prevalence of disease worldwide. Despite this, reports on the geographical distribution of disease and differences in mortality due to sarcoidosis within Northern Ireland (NI) and the Republic of Ireland (ROI) are currently lacking. OBJECTIVE: This study was performed to examine sarcoidosis prevalence and mortality in Ireland (NI and ROI) to specifically determine if geographical or temporal clusters of disease are present and if any differences in mortality exist between NI and ROI. DESIGN: A retrospective study, examining hospital discharge data for NI and ROI and data on deaths due to sarcoidosis, obtained from the relevant official government agencies. RESULTS: For 1996-2005, the prevalence of sarcoidosis was 28.13 per 100,000 for ROI compared with 11.16 per 100,000 for NI (p = 0.002). Two significant spatial clusters of disease were detected in the Northwest (Prevalence = 44.9 per 100,000) and also the Midlands region (32.1 per 100,000). Two lower-prevalence spatial clusters were also detected in the South and Southeast of ROI. Temporal clustering was also present throughout ROI and NI for the years 2000 to 2004, while space-time clustering was found in three regions, the West (ROI), the East (ROI) and Northeast (ROI and NI). The case fatality rate for ROI was 0.84%, and for NI was 1.44% (p = 0.03). CONCLUSION: Considerable heterogeneity in disease prevalence is evident in Ireland as significant spatial, temporal and space-time clusters of sarcoidosis are demonstrated in this study. Prevalence rates are also higher than that previously reported for Ireland and are comparable to those of Scandinavian countries. Although case-fatality is low in both ROI and NI, it is significantly lower in ROI. Further study is needed to investigate these findings and the creation of an all-island sarcoidosis registry would provide a mutually beneficial means of capturing this data more effectively.


Asunto(s)
Sarcoidosis Pulmonar/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Lactante , Irlanda/epidemiología , Masculino , Persona de Mediana Edad , Irlanda del Norte/epidemiología , Prevalencia , Sarcoidosis Pulmonar/mortalidad , Agrupamiento Espacio-Temporal , Adulto Joven
20.
Diabet Med ; 26(4): 447-50, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19388977

RESUMEN

AIMS: To assess the availability and types of psychological services for people with diabetes in the UK, compliance with national guidelines and skills of the diabetes team in, and attitudes towards, psychological aspects of diabetes management. METHODS: Postal questionnaires to team leads (doctor and nurse) of all UK diabetes centres (n = 464) followed by semi-structured telephone interviews of expert providers of psychological services identified by team leads. RESULTS: Two hundred and sixty-seven centres (58%) returned postal questionnaires; 66 (25%) identified a named expert provider of psychological services, of whom 53 (80%) were interviewed by telephone. Less than one-third (n = 84) of responding centres had access to specialist psychological services and availability varied across the four UK nations (P = 0.02). Over two-thirds (n = 182) of centres had not implemented the majority of national guidelines and only 2.6% met all guidelines. Psychological input into teams was associated with improved training in psychological issues for team members (P < 0.001), perception of better skills in managing more complex psychological issues (P < or = 0.01) and increased likelihood of having psychological care pathways (P < or = 0.05). Most (81%) expert providers interviewed by telephone were under-resourced to meet the psychological needs of their population. CONCLUSIONS: Expert psychological support is not available to the majority of diabetes centres and significant geographical variation indicates inequity of service provision. Only a minority of centres meet national guidelines. Skills and services within diabetes teams vary widely and are positively influenced by the presence of expert providers of psychological care. Lack of resources are a barrier to service provision.


Asunto(s)
Diabetes Mellitus/psicología , Consejo/organización & administración , Estudios Transversales , Atención a la Salud , Femenino , Necesidades y Demandas de Servicios de Salud , Humanos , Masculino , Guías de Práctica Clínica como Asunto , Encuestas y Cuestionarios
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