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2.
Obes Surg ; 31(5): 1986-1993, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33423181

RESUMEN

BACKGROUND: Obstructive sleep apnea (OSA) is an increasingly common disorder associated with increased cardiovascular disease, mortality, reduced productivity, and an increased risk of road traffic accidents. A significant proportion of patients with OSA in the UK are undiagnosed. This study aims to identify risk factors for OSA in an obese cohort. METHOD: A population-based study was conducted of obese patients (BMI ≥ 30 kg/m2) from the Clinical Practice Research Datalink (CPRD). A logistic regression model was used to calculate odds ratios (ORs) for developing OSA according to other clinicopathological characteristics. Multivariate analysis was conducted of individual factors that affect the propensity to develop OSA. Statistical significance was defined as p < 0.050. RESULTS: From 276,600 obese patients identified during a data extraction of the CPRD in July 2017, the prevalence of OSA was 5.4%. The following risk factors were found to be independently associated with increased likelihood of OSA: male sex (OR = 3.273; p < 0.001), BMI class II (OR = 1.640; p < 0.001), BMI class III (OR = 3.768; p < 0.001), smoking (OR = 1.179; p < 0.001), COPD (OR = 1.722; p < 0.001), GERD (OR = 1.557; p < 0.001), hypothyroidism (OR = 1.311; p < 0.001), acromegaly (OR = 3.543; p < 0.001), and benzodiazepine use (OR = 1.492; p < 0.001). Bariatric surgery was associated with reduced risk of OSA amongst this obese population (OR = 0.260; p < 0.001). CONCLUSIONS: In obese patients, there are numerous comorbidities that are associated with increased likelihood of OSA. These factors can help prompt clinicians to identify undiagnosed OSA. Bariatric surgery appears to be protective against developing OSA.


Asunto(s)
Obesidad Mórbida , Apnea Obstructiva del Sueño , Índice de Masa Corporal , Humanos , Masculino , Obesidad/complicaciones , Obesidad/epidemiología , Obesidad Mórbida/cirugía , Polisomnografía , Apnea Obstructiva del Sueño/complicaciones , Apnea Obstructiva del Sueño/epidemiología , Reino Unido/epidemiología
3.
Epilepsia ; 61(10): 2234-2243, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-33053223

RESUMEN

OBJECTIVE: To test whether children with epilepsy have impairments in myocardial mechanics compared to controls without epilepsy. METHODS: Children with refractory epilepsy with epilepsy duration of at least 3 years underwent echocardiography including conventional measurements and speckle tracking to assess longitudinal and circumferential strain. Parent-completed surveys, capturing critical aspects of the children's seizure history and cardiac risk factors, complemented retrospective chart reviews, which also included antiepileptic drug history. Normal echocardiograms from controls, matched for age and gender, were obtained from our institutional database and evaluated for strain. RESULTS: Forty-one patients (median age = 10 years, interquartile range [IQR] = 5-15; 58.5% male) were enrolled. Epilepsy etiology included genetic (n = 26), structural (n = 6), genetic and structural (n = 5), infection (n = 3), and unknown (n = 1). No cardiac structural abnormalities were identified. Both longitudinal and circumferential strain were impaired (P < .03) in patients compared to controls (median [IQR] = 22.7% [21.2-24.2] vs 23.6% [22.2-26.1] and 22.0% [20.3-25.4] vs 24.5% [22.3-27.0], respectively), indicating decreased myocardial deformation/contraction. Shortening fraction was higher in patients (37.6% [35.7-39.7] vs 34.9% [32.5-38.7], P = .009); mitral valve E wave inflow velocity (84.8 cm/s [78.4-92.8] vs 97.2 cm/s [85.9-105.8], P = .005) and tissue Doppler lateral E' wave (13.9 cm/s [12.3-16.1] vs 17.3 cm/s [15.4-18.5], P < .001) were decreased compared to controls. Findings were similar in the pairs with epilepsy patients distinguished by the ability to independently ambulate. There was no difference between patients and controls in ejection fraction. Among the epilepsy patients, there were no associations between cardiac measurements and epilepsy characteristics, including seizure type and frequency and cardiotoxic antiseizure medication exposure after correction for multiple comparisons. SIGNIFICANCE: Children with refractory epilepsy had impaired systolic ventricular strain compared to controls, not correlated with epilepsy history. Further studies are needed to determine the significance of these changes.


Asunto(s)
Epilepsia Refractaria/diagnóstico por imagen , Epilepsia Refractaria/fisiopatología , Cardiopatías/diagnóstico por imagen , Cardiopatías/fisiopatología , Contracción Miocárdica/fisiología , Muerte Súbita e Inesperada en la Epilepsia/prevención & control , Adolescente , Estudios de Casos y Controles , Niño , Epilepsia Refractaria/epidemiología , Ecocardiografía Doppler/métodos , Femenino , Cardiopatías/epidemiología , Humanos , Masculino , Estudios Prospectivos , Estudios Retrospectivos , Muerte Súbita e Inesperada en la Epilepsia/epidemiología
4.
Clin Radiol ; 69(12): 1259-63, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25239790

RESUMEN

AIM: To assess whether the size of peritumoural stiffness (PTS) on shear-wave elastography (SWE) for small primary breast cancers (≤15 mm) was associated with size discrepancies between grey-scale ultrasound (GSUS) and final histological size and whether the addition of PTS size to GSUS size might result in more accurate tumour size estimation when compared to final histological size. MATERIALS AND METHODS: A retrospective analysis of 86 consecutive patients between August 2011 and February 2013 who underwent breast-conserving surgery for tumours of size ≤15 mm at ultrasound was carried out. The size of PTS stiffness was compared to mean GSUS size, mean histological size, and the extent of size discrepancy between GSUS and histology. PTS size and GSUS were combined and compared to the final histological size. RESULTS: PTS of >3 mm was associated with a larger mean final histological size (16 versus 11.3 mm, p < 0.001). PTS size of >3 mm was associated with a higher frequency of underestimation of final histological size by GSUS of >5 mm (63% versus 18%, p < 0.001). The combination of PTS and GSUS size led to accurate estimation of the final histological size (p = 0.03). The size of PTS was not associated with margin involvement (p = 0.27). CONCLUSION: PTS extending beyond 3 mm from the grey-scale abnormality is significantly associated with underestimation of tumour size of >5 mm for small invasive breast cancers. Taking into account the size of PTS also led to accurate estimation of the final histological size. Further studies are required to assess the relationship of the extent of SWE stiffness and margin status.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Diagnóstico por Imagen de Elasticidad/métodos , Carga Tumoral/fisiología , Ultrasonografía Mamaria/métodos , Adulto , Anciano , Anciano de 80 o más Años , Mama/patología , Femenino , Humanos , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos
5.
Phys Rev Lett ; 113(26): 267604, 2014 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-25615386

RESUMEN

We experimentally demonstrate the first inductive readout of optically hyperpolarized phosphorus-31 donor nuclear spins in an isotopically enriched silicon-28 crystal. The concentration of phosphorus donors in the crystal was 1.5×10(15) cm(-3), 3 orders of magnitude lower than has previously been detected via direct inductive detection. The signal-to-noise ratio measured in a single free induction decay from a 1 cm(3) sample (≈10(15) spins) was 113. By transferring the sample to an X-band ESR spectrometer, we were able to obtain a lower bound for the nuclear spin polarization at 1.7 K of ∼64%. The (31)P-T2 measured with a Hahn echo sequence was 420 ms at 1.7 K, which was extended to 1.2 s with a Carr Purcell cycle. The T1 of the (31)P nuclear spins at 1.7 K is extremely long and could not be determined, as no decay was observed even on a time scale of 4.5 h. Optical excitation was performed with a 1047 nm laser, which provided above-band-gap excitation of the silicon. The buildup of the hyperpolarization at 4.2 K followed a single exponential with a characteristic time of 577 s, while the buildup at 1.7 K showed biexponential behavior with characteristic time constants of 578 and 5670 s.

6.
Ann R Coll Surg Engl ; 94(3): 170-2, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22507720

RESUMEN

INTRODUCTION: Nicorandil is a commonly prescribed antianginal medication that has been found to be associated with painful anal ulceration. The incidence of this complication is unknown. We have used the best data available to us to make an estimate of this figure in a health district with a remarkably stable population of approximately 200,000 people. METHODS: using an electronic search of all letters generated from colorectal and gastroenterology clinics as well as endoscopy reports from January 2004 to November 2010, patients with anal ulceration who were taking nicorandil were identified. Other causes of ulceration were excluded by biopsy in the majority of cases. The central hospital and community pharmacy database was interrogated to estimate the number of patients who were prescribed nicorandil over a six-year period (2004-2010). RESULTS: A total of 30 patients (24 men, 6 women) with a median age of 79.5 years were identified who fulfilled the criteria of: taking nicorandil; having no other identified cause for anal ulceration; and achieving eventual healing after withdrawal of nicorandil. In the six-year period an estimated mean of 1,379 patients were prescribed nicorandil each year. The mean annual incidence of anal ulcers among nicorandil users is therefore calculated to be in the region of 0.37%. CONCLUSIONS: Anal ulceration appears to occur in approximately four in every thousand patients prescribed nicorandil each year. Prescribing physicians should explain the risk of this unpleasant complication to their patients.


Asunto(s)
Fisura Anal/inducido químicamente , Nicorandil/efectos adversos , Vasodilatadores/efectos adversos , Anciano , Anciano de 80 o más Años , Angina de Pecho/tratamiento farmacológico , Inglaterra/epidemiología , Femenino , Fisura Anal/epidemiología , Humanos , Incidencia , Masculino , Persona de Mediana Edad
7.
J Surg Case Rep ; 2012(10): 16, 2012 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-24960756

RESUMEN

Aortic stent graft infection is a rare but serious complication associated with high mortality. This report emphasizes the need for continued awareness of potential graft-related septic complications in patients undergoing Endovascular Aortic Repair (EVAR). We report a case in which a post-EVAR patient became unwell about 30 days post operatively and was shown on CT scanning to have a psoas abscess. The abscess was managed with percutaneous drainage and antibiotics. The patient remains well with no evidence of psoas collection or perigraft infection one year on. We review the available literature and discuss the merits of different management strategies.

8.
Eur J Vasc Endovasc Surg ; 42(5): 591-5, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21703885

RESUMEN

OBJECTIVES: We aimed to survey the current management of venous thromboprophylaxis in patients undergoing elective surgery for abdominal aortic aneurysm (AAA) by vascular surgeons in the United Kingdom. DESIGN: A questionnaire was designed to investigate anticoagulation strategies in the perioperative period of elective AAA repair, both open and endovascular. This included both chemical and mechanical prophylaxis. A total of 395 questionnaires was posted to the members of the Vascular Society of Great Britain and Ireland. RESULTS: One hundred and seventy-two (44%) valid responses were received. Half of the respondents administered pre-operative chemical prophylaxis at a mean of 13 h prior to AAA surgery. There was a high level of concordance in administration of heparin during surgery and in thromboprophylaxis post-operatively, with 97% giving some form of thromboprophylaxis. However there was a variation in the dose and timing, if administered, of chemical and mechanical prophylaxis. CONCLUSION: The survey revealed diversity in perioperative thromboprophylaxis strategies among vascular surgeons. This suggests that standardisation of pre-operative and post-operative mechanical and chemical thromboprophylaxis may be required which could potentially improve the outcomes in elective management of AAA in the UK.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Complicaciones Posoperatorias , Tromboembolia Venosa/prevención & control , Aneurisma de la Aorta Abdominal/complicaciones , Quimioprevención , Protocolos Clínicos , Procedimientos Quirúrgicos Electivos , Procedimientos Endovasculares , Fibrinolíticos/administración & dosificación , Encuestas de Atención de la Salud , Heparina/administración & dosificación , Humanos , Pautas de la Práctica en Medicina , Reino Unido , Tromboembolia Venosa/etiología
9.
Int J Tuberc Lung Dis ; 14(4): 506-12, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20202311

RESUMEN

BACKGROUND: Allergic rhinitis (AR) affects 5% to 40% of the general population. In developing countries, AR is poorly documented and tracked due to a lack of appropriate diagnostic tools. OBJECTIVE: 1) To validate a questionnaire standardised in industrialised countries to ascertain AR, the Score For Allergic Rhinitis (SFAR), in developing countries; 2) to better understand AR prevalence previously reported from developing countries by comparing results from the SFAR and the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaires. METHODS: Six African countries were selected for their climates. In each country, 70 individuals with and 30 without nasal symptoms filled out the SFAR and the ISAAC questionnaires. Skin prick tests (SPTs) for allergens were performed by the physician if necessary. RESULTS: The SFAR presented a close match with the gold standard (the physician's diagnosis of AR backed up by SPT where necessary) in terms of various performance parameters. In particular, it showed high sensitivity (0.84) and specificity (0.81). Compared to the ISAAC questionnaire, the SFAR had greater sensitivity and equal specificity. CONCLUSIONS: In the absence of a medical visit, the SFAR is a useful standardised screening instrument for the collection of information needed for the identification of AR in developing countries.


Asunto(s)
Países en Desarrollo , Tamizaje Masivo/métodos , Rinitis Alérgica Perenne/diagnóstico , Rinitis Alérgica Estacional/diagnóstico , Encuestas y Cuestionarios , Adolescente , Adulto , África/epidemiología , Anciano , Niño , Femenino , Humanos , Pruebas Intradérmicas , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Prevalencia , Reproducibilidad de los Resultados , Rinitis Alérgica Perenne/epidemiología , Rinitis Alérgica Estacional/epidemiología , Estaciones del Año , Índice de Severidad de la Enfermedad , Adulto Joven
10.
Phys Rev Lett ; 103(25): 250501, 2009 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-20366244

RESUMEN

We present experimental results approximating the Jones polynomial using 4 qubits in a liquid state nuclear magnetic resonance quantum information processor. This is the first experimental implementation of a complete problem for the deterministic quantum computation with one quantum bit model of quantum computation, which uses a single qubit accompanied by a register of completely random states. The Jones polynomial is a knot invariant that is important not only to knot theory, but also to statistical mechanics and quantum field theory. The implemented algorithm is a modification of the algorithm developed by Shor and Jordan suitable for implementation in NMR. These experimental results show that for the restricted case of knots whose braid representations have four strands and exactly three crossings, identifying distinct knots is possible 91% of the time.

11.
Phys Rev Lett ; 100(14): 140501, 2008 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-18518015

RESUMEN

We experimentally demonstrate multiple rounds of heat-bath algorithmic cooling in a 3 qubit solid-state nuclear magnetic resonance quantum information processor. By pumping entropy into a heat bath, we are able to surpass the closed system limit of the Shannon bound and purify a single qubit to 1.69 times the heat-bath polarization. The algorithm combines both high fidelity coherent control and a deliberate interaction with the environment. Given this level of quantum control in systems with larger reset polarizations, nearly pure qubits should be achievable.

12.
Oncogene ; 27(1): 55-62, 2008 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-17603559

RESUMEN

Recently, we reported prognostic significance of thromboxane synthase (TXAS) gene expression in invasive bladder cancer. The positive correlation between elevated TXAS expression and shorter patient survival supports a potential role for TXAS-regulated pathways in tumor metastases. In this study, using immunohistochemical analysis, we found an increased expression of TXAS protein in bladder cancer. Treatment of T24 and transitional cell carcinoma TCC-SUP bladder cancer cells with the TXAS inhibitors furegrelate or ozagrel induced an apoptotic effect measured as an increase in caspase-3 activation and cell death, and decreased survivin expression. Pharmacological inhibition of TXAS using the TXAS inhibitor furegrelate increased sensitivity to the chemotherapeutic agents cisplatin and paclitaxel. Molecular inhibition of TXAS expression by siRNA significantly decreased cell growth and migration. In concordance with the pharmacological data, siRNA-mediated reduction of TXAS expression increased sensitivity to cisplatin and paclitaxel in T24 and TCC-SUP cells. In summary, the data support a role for the thromboxane A(2) pathway in the pathogenesis of bladder cancer and the potential utility of modulation of this signaling pathway for cancer chemotherapy.


Asunto(s)
Antineoplásicos/toxicidad , Tromboxano-A Sintasa/antagonistas & inhibidores , Tromboxano-A Sintasa/metabolismo , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/enzimología , Proteínas Reguladoras de la Apoptosis/antagonistas & inhibidores , Proteínas Reguladoras de la Apoptosis/metabolismo , Proteínas Reguladoras de la Apoptosis/fisiología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cisplatino/toxicidad , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Humanos , Inmunohistoquímica , Invasividad Neoplásica , Paclitaxel/toxicidad , Tromboxano-A Sintasa/fisiología , Células Tumorales Cultivadas , Neoplasias de la Vejiga Urinaria/patología
13.
Parasite Immunol ; 30(1): 47-51, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18086016

RESUMEN

Plasmodium falciparum infection can lead to a life threatening disease and the pathogenetic mechanisms of severe manifestations are not fully understood. Here, we investigated the capacity of P. falciparum-parasitized red blood cells (PRBC) from 45 children with clinical malaria to induce endothelial cell (EC) apoptosis. In all subjects, PRBC that cytoadhered to ECs could be found albeit to a variable degree. By contrast, PRBC that induce EC apoptosis were found only in nine (20%) subjects. Interestingly, children with neurological manifestations were significantly more likely to harbour apoptogenic strains. There was no quantitative relationship between the capacity of these isolates to cytoadhere and apoptosis induction. We hypothesize that P. falciparum-encoded molecules could be responsible for apoptosis induction and therefore suggest new insights in the pathogenesis of P. falciparum malaria. Further investigations are currently in progress to determine whether these results can be confirmed and to identify putative parasite apoptogenic factors.


Asunto(s)
Apoptosis , Células Endoteliales/patología , Eritrocitos/fisiología , Eritrocitos/parasitología , Malaria Falciparum/parasitología , Enfermedades del Sistema Nervioso/parasitología , Plasmodium falciparum/patogenicidad , Animales , Adhesión Celular , Células Cultivadas , Niño , Preescolar , Células Endoteliales/metabolismo , Humanos , Lactante , Malaria Cerebral/parasitología , Malaria Falciparum/sangre , Malaria Falciparum/patología , Enfermedades del Sistema Nervioso/metabolismo , Enfermedades del Sistema Nervioso/patología , Parasitemia , Plasmodium falciparum/aislamiento & purificación
14.
Nature ; 438(7067): 470-3, 2005 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-16306986

RESUMEN

The counter-intuitive properties of quantum mechanics have the potential to revolutionize information processing by enabling the development of efficient algorithms with no known classical counterparts. Harnessing this power requires the development of a set of building blocks, one of which is a method to initialize the set of quantum bits (qubits) to a known state. Additionally, fresh ancillary qubits must be available during the course of computation to achieve fault tolerance. In any physical system used to implement quantum computation, one must therefore be able to selectively and dynamically remove entropy from the part of the system that is to be mapped to qubits. One such method is an 'open-system' cooling protocol in which a subset of qubits can be brought into contact with an external system of large heat capacity. Theoretical efforts have led to an implementation-independent cooling procedure, namely heat-bath algorithmic cooling. These efforts have culminated with the proposal of an optimal algorithm, the partner-pairing algorithm, which was used to compute the physical limits of heat-bath algorithmic cooling. Here we report the experimental realization of multi-step cooling of a quantum system via heat-bath algorithmic cooling. The experiment was carried out using nuclear magnetic resonance of a solid-state ensemble three-qubit system. We demonstrate the repeated repolarization of a particular qubit to an effective spin-bath temperature, and alternating logical operations within the three-qubit subspace to ultimately cool a second qubit below this temperature. Demonstration of the control necessary for these operations represents an important step forward in the manipulation of solid-state nuclear magnetic resonance qubits.

15.
J Urol ; 164(2): 584-8, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10893648

RESUMEN

OBJECTIVE: To establish a polymerase chain reaction (PCR) assay for the rapid detection and identification of mycobacteria in urine, and to assess the value of such assay in routine laboratory diagnosis of genitourinary tuberculosis. MATERIALS AND METHODS: Urine specimens from 1000 patients with clinical suspicion of urinary tuberculosis were examined. Two assays for the detection and identification of Mycobacterium tuberculosis (M. tuberculosis) complex and mycobacteria other than tuberculosis (MOTT) by non-radioactive DNA hybridization of PCR-product were applied. The first assay used PCR primers and probe derived from M. tuberculosis species-specific DNA insertion sequence, IS6110. The second utilized mycobacterium genus-specific sequence encoding ribosomal ribonucleic acid (16S rRNA). The results obtained by PCR were compared with those obtained by standard microbiological methods, acid-fast bacilli (AFB) stain and culture. RESULTS: Compared with cultures, the sensitivity of AFB staining was 52.07% and the specificity was 96.7%. In comparison to the results of culture, the overall sensitivity and specificity of the IS6110-PCR assay was 95.59% and 98.12% respectively. While the corresponding results for the 16S rRNA gene-PCR were 87.05% and 98. 9%. CONCLUSION: The high sensitivity and specificity in addition to the potential for rapid detection of mycobacteria, makes this test a useful tool in the clinical management of mycobacterial infection in urine. Urine specimens may contain M. tuberculosis and/or other mycobacteria; therefore, there are advantages in using genus-specific primers in parallel with species-specific primers in PCR assay.


Asunto(s)
Hibridación de Ácido Nucleico , Reacción en Cadena de la Polimerasa , Tuberculosis Urogenital/diagnóstico , Cartilla de ADN , ADN Bacteriano/análisis , Humanos , Mycobacterium/aislamiento & purificación , Mycobacterium tuberculosis/aislamiento & purificación , Sensibilidad y Especificidad , Tuberculosis Urogenital/microbiología , Orina/microbiología
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