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1.
Occup Med (Lond) ; 72(4): 273-275, 2022 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-35411398

RESUMEN

Cannabis allergy is not commonly reported, perhaps due to the legal status of cannabis use and the difficulties of obtaining permission to test it. We report 3 cases of work-related cannabis allergy with features suggestive of a dermatitis, rather than a contact urticaria. Only prick tests were able to confirm the diagnosis. Identification of the cause of the rash was essential to direct work re-deployment.


Asunto(s)
Cannabis , Dermatitis Alérgica por Contacto , Dermatitis Profesional , Urticaria , Cannabis/efectos adversos , Dermatitis Alérgica por Contacto/etiología , Dermatitis Profesional/diagnóstico , Dermatitis Profesional/etiología , Humanos , Pruebas Cutáneas , Urticaria/diagnóstico , Urticaria/etiología
2.
Langmuir ; 37(4): 1578-1587, 2021 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-33478219

RESUMEN

Microwell arrays are amongst the most commonly used platforms for biochemical assays. However, the coalescence of droplets that constitute the dispersed phase of suspensions housed within microwells has not received much attention to date. Herein, we study the coalescence of droplets in a two-phase system in a microwell driven by surface acoustic waves (SAWs). The microwell structure, together with symmetric exposure to SAW irradiation, coupled from beneath the microwell via a piezoelectric substrate, gives rise to the formation of a pair of counter-rotating vortices that enable droplet transport, trapping, and coalescence. We elucidate the physics of the coalescence phenomenon using a scaling analysis of the relevant forces, namely, the acoustic streaming-induced drag force, the capillary and viscous forces associated with the drainage of the thin continuous phase film between the droplets and the van der Waals attraction force. We confirm that droplet-droplet interface contact is established through the formation of a liquid bridge, whose neck radius grows linearly in time in the preceding viscous regime and proportionally with the square root of time in the subsequent inertial regime. Further, we investigate the influence of the input SAW power and droplet size on the film drainage time and demarcate the coalescence and non-coalescence regimes to derive a criterion for the onset of coalescence. The distinct deformation patterns observed for a pair of contacting droplets in both the regimes are elucidated and the possibility for driving concurrent coalescence of multiple droplets is demonstrated. We expect the study will find relevance in the demulsification of immiscible phases and the mixing of samples/reagents within microwells for a variety of biochemical applications.

3.
Clin Exp Immunol ; 199(3): 263-277, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31660582

RESUMEN

In type 1 diabetes (T1D), autoreactive cytotoxic CD8+ T cells are implicated in the destruction of insulin-producing ß cells. The HLA-B*3906 and HLA-A*2402 class I genes confer increased risk and promote early disease onset, suggesting that CD8+ T cells that recognize peptides presented by these class I molecules on pancreatic ß cells play a pivotal role in the autoimmune response. We examined the frequency and phenotype of circulating preproinsulin (PPI)-specific and insulin B (InsB)-specific CD8+ T cells in HLA-B*3906+ children newly diagnosed with T1D and in high-risk HLA-A*2402+ children before the appearance of disease-specific autoantibodies and before diagnosis of T1D. Antigen-specific CD8+ T cells were detected using human leucocyte antigen (HLA) class I tetramers and flow cytometry was used to assess memory status. In HLA-B*3906+ children with T1D, we observed an increase in PPI5-12 -specific transitional memory CD8+ T cells compared to non-diabetic, age- and HLA-matched subjects. Furthermore, PPI5-12 -specific CD8+ T cells in HLA-B*3906+ children with T1D showed a significantly more antigen-experienced phenotype compared to polyclonal CD8+ T cells. In longitudinal samples from high-risk HLA-A*2402+ children, the percentage of terminal effector cells within the InsB15-24 -specific CD8+ T cells was increased before diagnosis relative to samples taken before the appearance of autoantibodies. This is the first study, to our knowledge, to report HLA-B*3906-restricted autoreactive CD8+ T cells in T1D. Collectively, our results provide evidence that ß cell-reactive CD8+ T cells restricted by disease-associated HLA class I molecules display an antigen-experienced phenotype and acquire enhanced effector function during the period leading to clinical diagnosis, implicating these cells in driving disease.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Diabetes Mellitus Tipo 1/inmunología , Antígenos de Histocompatibilidad Clase I/inmunología , Células Secretoras de Insulina/inmunología , Autoinmunidad/inmunología , Linfocitos T CD8-positivos/metabolismo , Niño , Preescolar , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/metabolismo , Femenino , Antígeno HLA-A24/inmunología , Antígeno HLA-A24/metabolismo , Antígenos HLA-B/inmunología , Antígenos HLA-B/metabolismo , Antígenos de Histocompatibilidad Clase I/metabolismo , Humanos , Lactante , Insulina/inmunología , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Masculino , Precursores de Proteínas/inmunología , Precursores de Proteínas/metabolismo , Factores de Riesgo
4.
Ultrasound Obstet Gynecol ; 55(2): 177-188, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31006913

RESUMEN

OBJECTIVE: To compare the predictive performance of estimated fetal weight (EFW) percentiles, according to eight growth standards, to detect fetuses at risk for adverse perinatal outcome. METHODS: This was a retrospective cohort study of 3437 African-American women. Population-based (Hadlock, INTERGROWTH-21st , World Health Organization (WHO), Fetal Medicine Foundation (FMF)), ethnicity-specific (Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)), customized (Gestation-Related Optimal Weight (GROW)) and African-American customized (Perinatology Research Branch (PRB)/NICHD) growth standards were used to calculate EFW percentiles from the last available scan prior to delivery. Prediction performance indices and relative risk (RR) were calculated for EFW < 10th and > 90th percentiles, according to each standard, for individual and composite adverse perinatal outcomes. Sensitivity at a fixed (10%) false-positive rate (FPR) and partial (FPR < 10%) and full areas under the receiver-operating-characteristics curves (AUC) were compared between the standards. RESULTS: Ten percent (341/3437) of neonates were classified as small-for-gestational age (SGA) at birth, and of these 16.4% (56/341) had at least one adverse perinatal outcome. SGA neonates had a 1.5-fold increased risk of any adverse perinatal outcome (P < 0.05). The screen-positive rate of EFW < 10th percentile varied from 6.8% (NICHD) to 24.4% (FMF). EFW < 10th percentile, according to all standards, was associated with an increased risk for each of the adverse perinatal outcomes considered (P < 0.05 for all). The highest RRs associated with EFW < 10th percentile for each adverse outcome were 5.1 (95% CI, 2.1-12.3) for perinatal mortality (WHO); 5.0 (95% CI, 3.2-7.8) for perinatal hypoglycemia (NICHD); 3.4 (95% CI, 2.4-4.7) for mechanical ventilation (NICHD); 2.9 (95% CI, 1.8-4.6) for 5-min Apgar score < 7 (GROW); 2.7 (95% CI, 2.0-3.6) for neonatal intensive care unit (NICU) admission (NICHD); and 2.5 (95% CI, 1.9-3.1) for composite adverse perinatal outcome (NICHD). Although the RR CIs overlapped among all standards for each individual outcome, the RR of composite adverse perinatal outcome in pregnancies with EFW < 10th percentile was higher according to the NICHD (2.46; 95% CI, 1.9-3.1) than the FMF (1.47; 95% CI, 1.2-1.8) standard. The sensitivity for composite adverse perinatal outcome varied substantially between standards, ranging from 15% for NICHD to 32% for FMF, due mostly to differences in FPR; this variation subsided when the FPR was set to the same value (10%). Analysis of AUC revealed significantly better performance for the prediction of perinatal mortality by the PRB/NICHD standard (AUC = 0.70) compared with the Hadlock (AUC = 0.66) and FMF (AUC = 0.64) standards. Evaluation of partial AUC (FPR < 10%) demonstrated that the INTERGROWTH-21st standard performed better than the Hadlock standard for the prediction of NICU admission and mechanical ventilation (P < 0.05 for both). Although fetuses with EFW > 90th percentile were also at risk for any adverse perinatal outcome according to the INTERGROWTH-21st (RR = 1.4; 95% CI, 1.0-1.9) and Hadlock (RR = 1.7; 95% CI, 1.1-2.6) standards, many times fewer cases (2-5-fold lower sensitivity) were detected by using EFW > 90th percentile, rather than EFW < 10th percentile, in screening by these standards. CONCLUSIONS: Fetuses with EFW < 10th percentile or EFW > 90th percentile were at increased risk of adverse perinatal outcomes according to all or some of the eight growth standards, respectively. The RR of a composite adverse perinatal outcome in pregnancies with EFW < 10th percentile was higher for the most-stringent (NICHD) compared with the least-stringent (FMF) standard. The results of the complementary analysis of AUC suggest slightly improved detection of adverse perinatal outcome by more recent population-based (INTERGROWTH-21st ) and customized (PRB/NICHD) standards compared with the Hadlock and FMF standards. Published 2019. This article is a U.S. Government work and is in the public domain in the USA.


Asunto(s)
Biometría/métodos , Retardo del Crecimiento Fetal/diagnóstico , Feto/diagnóstico por imagen , Medición de Riesgo/métodos , Ultrasonografía Prenatal/estadística & datos numéricos , Adulto , Negro o Afroamericano/estadística & datos numéricos , Área Bajo la Curva , Femenino , Retardo del Crecimiento Fetal/etnología , Peso Fetal/etnología , Humanos , Recién Nacido , Recién Nacido Pequeño para la Edad Gestacional , Muerte Perinatal/etiología , Mortalidad Perinatal/etnología , Valor Predictivo de las Pruebas , Embarazo , Curva ROC , Estándares de Referencia , Valores de Referencia , Estudios Retrospectivos , Medición de Riesgo/normas , Sensibilidad y Especificidad
5.
Public Health ; 176: 106-113, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30509859

RESUMEN

OBJECTIVES: This study was undertaken to investigate the occurrence of metabolic syndrome (MetS) and cardiovascular disease (CVD) risk in Orang Asli (OA), the indigenous people of Peninsular Malaysia. OA consist of Negrito, Proto-Malay, and Senoi groups who collectively comprise only 0.76% of the population of Peninsular Malaysia. Owing to the challenges in accessing their remote villages, these groups are often excluded in larger government health surveys. Although tropical diseases were scourges in the past, with rapid national development, many OA communities have been gradually urbanized. We believe an epidemiological transition is occurring and non-communicable diseases are on the rise. STUDY DESIGN: A retrospective cross-sectional study. METHODS: Indigenous Malaysians (n = 629) from three major groups (Negrito, Proto-Malay, and Senoi) were recruited, after ethics approval and informed consent. Body mass index (BMI), body weight, height, waist circumference, and systolic and diastolic blood pressure were measured, and participants were examined for acanthosis nigricans. Venous blood samples were used for measurements of fasting blood sugar, triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C). Insulin resistance was estimated using a surrogate measurement TG/HDL-C. The ratios of TC to HDL-C, and of LDL-C to HDL-C were determined. MetS was accessed according to the Joint Interim Statement of the IDF Tsak Force on Epidemiology and Prevention. RESULTS: MetS affected 29.57% of the OA population investigated and was significantly more prevalent (P < 0.05) in women than in men (35.25% vs 21.95%, P < 0.001). MetS prevalence was the highest among the Proto-Malays (39.56%), followed by Negritos (26.35%) and Senois (11.26%). The most prevalent risk factor among the Negritos with MetS was low HDL-C (95.35%), whereas central obesity was the most common risk factor among the Proto-Malays (82.91%). In contrast, hypertension was the commonest risk factor among the Senois with MetS (94.44%). Elevated TG/HDL-C ratios resulted in the highest risk for MetS among the OA population (relative risk [RR] = 7.01, 95% confidence interval [CI] = 3.58-13.72). The risk was almost four-fold among those with high TG (RR = 3.89, 95% CI = 3.08-4.91) and three-fold among those with BMI obesity (RR = 3.37, 95% CI = 2.61-4.36) and central obesity (RR = 2.99, 95% CI = 2.48-3.61). CONCLUSIONS: This may well be the first comprehensive report about MetS in OA indigenous communities in Malaysia. We have shown that rapidly urbanized OA communities had significant prevalence of MetS and associated cardiometabolic risk factors. Major contributory factors may include changes from previous hunter-gatherer lifestyles and subsistence diets to more urbanized lifestyles and easier access to high calorie foods.


Asunto(s)
Enfermedades Cardiovasculares/etnología , Síndrome Metabólico/etnología , Grupos de Población/estadística & datos numéricos , Adulto , Estudios Transversales , Femenino , Humanos , Malasia/epidemiología , Masculino , Prevalencia , Estudios Retrospectivos , Factores de Riesgo
6.
Ultrasound Obstet Gynecol ; 50(4): 476-491, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28809063

RESUMEN

OBJECTIVE: To evaluate the performance of color and bidirectional power Doppler ultrasound combined with Fetal Intelligent Navigation Echocardiography (FINE) in examining the fetal heart. METHODS: A prospective cohort study was conducted of fetuses in the second and third trimesters with a normal heart or with congenital heart disease (CHD). One or more spatiotemporal image correlation (STIC) volume datasets, combined with color or bidirectional power Doppler (S-flow) imaging, were acquired in the apical four-chamber view. Each successfully obtained STIC volume was evaluated by STICLoop™ to determine its appropriateness before applying the FINE method. Visualization rates for standard fetal echocardiography views using diagnostic planes and/or Virtual Intelligent Sonographer Assistance (VIS-Assistance®) were calculated for grayscale (removal of Doppler signal), color Doppler and S-flow Doppler. In four cases with CHD (one case each of tetralogy of Fallot, hypoplastic left heart and coarctation of the aorta, interrupted inferior vena cava with azygos vein continuation and asplenia, and coarctation of the aorta with tricuspid regurgitation and hydrops), the diagnostic potential of this new technology was presented. RESULTS: A total of 169 STIC volume datasets of the normal fetal heart (color Doppler, n = 78; S-flow Doppler, n = 91) were obtained from 37 patients. Only a single STIC volume of color Doppler and/or a single volume of S-flow Doppler per patient were analyzed using FINE. Therefore, 60 STIC volumes (color Doppler, n = 27; S-flow Doppler, n = 33) comprised the final study group. Median gestational age at sonographic examination was 23 (interquartile range, 21-27.5) weeks. Color Doppler FINE generated nine fetal echocardiography views (grayscale) using (1) diagnostic planes in 73-100% of cases, (2) VIS-Assistance in 100% of cases, and (3) a combination of diagnostic planes and/or VIS-Assistance in 100% of cases. The rate of generating successfully eight fetal echocardiography views with appropriate color and S-flow Doppler information was 89-100% and 91-100% of cases, respectively, using a combination of diagnostic planes and/or VIS-Assistance. However, the success rate for the ninth echocardiography view (i.e. superior and inferior venae cavae) was 33% and 30% for color and S-flow Doppler, respectively. In all four cases of CHD, color Doppler FINE demonstrated evidence of abnormal fetal cardiac anatomy and/or hemodynamic flow. CONCLUSIONS: The FINE method applied to STIC volumes of normal fetal hearts acquired with color or bidirectional power Doppler information can generate successfully eight to nine standard fetal echocardiography views (via grayscale, color Doppler or power Doppler) in the second and third trimesters. In cases of CHD, color Doppler FINE demonstrates successfully abnormal anatomy and/or Doppler flow characteristics. Published 2017. This article is a U.S. Government work and is in the public domain in the USA. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Ecocardiografía Doppler en Color , Corazón Fetal/diagnóstico por imagen , Cardiopatías Congénitas/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Ultrasonografía Prenatal , Adulto , Femenino , Corazón Fetal/fisiopatología , Edad Gestacional , Cardiopatías Congénitas/fisiopatología , Humanos , Embarazo , Estudios Prospectivos , Ultrasonografía Prenatal/métodos , Adulto Joven
7.
Ann Rheum Dis ; 75(4): 763-71, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25858640

RESUMEN

BACKGROUND AND OBJECTIVES: For our understanding of the pathogenesis of rheumatoid arthritis (RA), it is important to elucidate the mechanisms underlying early stages of synovitis. Here, synovial cytokine production was investigated in patients with very early arthritis. METHODS: Synovial biopsies were obtained from patients with at least one clinically swollen joint within 12 weeks of symptom onset. At an 18-month follow-up visit, patients who went on to develop RA, or whose arthritis spontaneously resolved, were identified. Biopsies were also obtained from patients with RA with longer symptom duration (>12 weeks) and individuals with no clinically apparent inflammation. Synovial mRNA expression of 117 cytokines was quantified using PCR techniques and analysed using standard and novel methods of data analysis. Synovial tissue sections were stained for CXCL4, CXCL7, CD41, CD68 and von Willebrand factor. RESULTS: A machine learning approach identified expression of mRNA for CXCL4 and CXCL7 as potentially important in the classification of early RA versus resolving arthritis. mRNA levels for these chemokines were significantly elevated in patients with early RA compared with uninflamed controls. Significantly increased CXCL4 and CXCL7 protein expression was observed in patients with early RA compared with those with resolving arthritis or longer established disease. CXCL4 and CXCL7 co-localised with blood vessels, platelets and CD68(+) macrophages. Extravascular CXCL7 expression was significantly higher in patients with very early RA compared with longer duration RA or resolving arthritis CONCLUSIONS: Taken together, these observations suggest a transient increase in synovial CXCL4 and CXCL7 levels in early RA.


Asunto(s)
Artritis Reumatoide/genética , Citocinas/genética , Macrófagos/metabolismo , Factor Plaquetario 4/genética , ARN Mensajero/metabolismo , Membrana Sinovial/metabolismo , beta-Tromboglobulina/genética , Adulto , Anciano , Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Artritis Reumatoide/metabolismo , Citocinas/metabolismo , Progresión de la Enfermedad , Femenino , Técnica del Anticuerpo Fluorescente , Humanos , Inmunohistoquímica , Aprendizaje Automático , Masculino , Persona de Mediana Edad , Factor Plaquetario 4/metabolismo , Glicoproteína IIb de Membrana Plaquetaria/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Membrana Sinovial/citología , beta-Tromboglobulina/metabolismo , Factor de von Willebrand/metabolismo
8.
Ultrasound Obstet Gynecol ; 47(4): 450-9, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26278116

RESUMEN

OBJECTIVE: To evaluate prospectively the performance of Fetal Intelligent Navigation Echocardiography (FINE) applied to spatiotemporal image correlation (STIC) volume datasets of the normal fetal heart. METHODS: In all women between 19 and 30 weeks' gestation with a normal fetal heart, an attempt was made to acquire STIC volume datasets of the apical four-chamber view if the following criteria were met: (1) fetal spine located between 5- and 7-o'clock positions; (2) minimal or absent shadowing (including a clearly visible transverse aortic arch); (3) absence of fetal breathing, hiccups, or movement; and (4) adequate image quality. Each STIC volume successfully acquired was evaluated by STICLoop™ to determine its appropriateness before applying the FINE method. Visualization rates of fetal echocardiography views using diagnostic planes and/or Virtual Intelligent Sonographer Assistance (VIS-Assistance®) were calculated. RESULTS: One or more STIC volumes (365 in total) were obtained successfully in 72.5% (150/207) of women undergoing ultrasound examination. Of the 365 volumes evaluated by STICLoop, 351 (96.2%) were considered to be appropriate. From the 351 STIC volumes, only one STIC volume per patient (n = 150) was analyzed using the FINE method, and consequently nine fetal echocardiography views were generated in 76-100% of cases using diagnostic planes only, in 98-100% of cases using VIS-Assistance only, and in 98-100% of cases when using a combination of diagnostic planes and/or VIS-Assistance. CONCLUSIONS: In women between 19 and 30 weeks' gestation with a normal fetal heart undergoing prospective sonographic examination, STIC volumes can be obtained successfully in 72.5% of cases. The FINE method can be applied to generate nine standard fetal echocardiography views in 98-100% of these cases using a combination of diagnostic planes and/or VIS-Assistance. This suggests that FINE could be implemented in fetal cardiac screening programs. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.


Asunto(s)
Ecocardiografía/métodos , Corazón Fetal/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Ultrasonografía Prenatal/métodos , Adulto , Volumen Cardíaco , Femenino , Edad Gestacional , Humanos , Embarazo , Estudios Prospectivos
9.
Ann Rheum Dis ; 74(5): 928-35, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-24431391

RESUMEN

OBJECTIVES: The success of B cell targeting therapies has highlighted the importance of B cells in rheumatoid arthritis pathogenesis. We have previously shown that B cells in the RA synovium are capable of producing pro-inflammatory and bone-destructive cytokines including RANKL. Here we sought to characterise the nature and functional relevance of the RANKL-producing B cell subset in the RA synovium. METHODS: Synovial fluid and peripheral blood B cells from patients with RA were analysed by flow cytometry for markers of B cell differentiation and activation and for chemokine receptors. FcRL4(+) and FcRL4(-) B cells sorted from synovial fluid were analysed for cytokine expression using Taqman low-density arrays. Synovial tissue biopsies obtained from patients with RA were analysed by immunofluorescence for CD20, RANKL and FcRL4. FCRL4 mRNA expression was determined in synovial tissue of RA patients and non-inflammatory control subjects by real-time PCR. RESULTS: RANKL-producing B cells in RA synovial tissue and fluid were identified as belonging to a distinct subset of B cells defined by expression of the transmembrane protein FcRL4. FcRL4+ B cells express a distinct combination of cytokines and surface proteins indicating a function distinct from that of FcRL4- B cells. Notably, FcRL4+ B cells expressed high levels of TNF-α and RANKL mRNA. CONCLUSIONS: We have identified a novel pro-inflammatory B cell population in the RA synovium which is defined by expression of FcRL4 and responsible for RANKL production. This B cell population expresses high levels of CD20, and its removal by rituximab may contribute to the anti-inflammatory effect of this drug.


Asunto(s)
Artritis Reumatoide/inmunología , Subgrupos de Linfocitos B/inmunología , Ligando RANK/genética , ARN Mensajero/metabolismo , Receptores Fc/genética , Membrana Sinovial/metabolismo , Factor de Necrosis Tumoral alfa/genética , Adulto , Anciano , Antígenos CD20/metabolismo , Artritis Reumatoide/genética , Artritis Reumatoide/metabolismo , Subgrupos de Linfocitos B/metabolismo , Estudios de Casos y Controles , Diferenciación Celular , Femenino , Humanos , Activación de Linfocitos , Masculino , Persona de Mediana Edad , Ligando RANK/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores Fc/metabolismo , Líquido Sinovial , Factor de Necrosis Tumoral alfa/metabolismo
10.
Clin Exp Dermatol ; 40(8): 872-4, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25546496

RESUMEN

A 28-year-old man presented with a 1-year history of a localized patch of grey hair and an underlying darkly pigmented lesion on his right occipital area. Clinical appearance revealed poliosis overlying an asymmetrical plaque with variable degrees of brown pigmentation and white discolouration. Owing to the suspicious nature of the lesion, excision with a 2 mm margin was performed. Histology revealed an invasive melanoma with extensive regression and prominent involvement of multiple hair follicles. Scalp melanoma with associated poliosis is extremely rare, and has only been reported once in the literature to date. There have been two reports in the opthalmology literature regarding eyelash poliosis associated with orbital melanoma. The pathogenesis of poliosis still remains unclear. This is the second reported case of poliosis circmscripta unmasking a scalp melanoma, and highlights the importance of being vigilant when examining patients with poliosis of the scalp.


Asunto(s)
Enfermedades del Cabello/patología , Neoplasias de Cabeza y Cuello/patología , Hiperpigmentación/patología , Melanoma/patología , Cuero Cabelludo/patología , Neoplasias Cutáneas/patología , Adulto , Humanos , Masculino
11.
Phys Rev Lett ; 113(21): 215503, 2014 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-25479504

RESUMEN

We theoretically and experimentally demonstrate the existence of complete surface acoustic wave band gaps in surface phonon-polariton phononic crystals, in a completely monolithic structure formed from a two-dimensional honeycomb array of hexagonal shape domain-inverted inclusions in single crystal piezoelectric Z-cut lithium niobate. The band gaps appear at a frequency of about twice the Bragg band gap at the center of the Brillouin zone, formed through phonon-polariton coupling. The structure is mechanically, electromagnetically, and topographically homogeneous, without any physical alteration of the surface, offering an ideal platform for many acoustic wave applications for photonics, phononics, and microfluidics.

12.
Br J Dermatol ; 169(5): 983-91, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23782060

RESUMEN

A number of studies have suggested that early life exposure to antibiotics can lead to an increased risk of developing eczema. This systematic review and meta-analysis of observational studies, involving children or young adults aged 0-25 years, assessed the impact of antibiotic exposure either in utero or during the first 12 months of life on subsequent eczema risk. Twenty studies examined the association between prenatal and/or postnatal exposure to antibiotics and development of eczema. The pooled odds ratio (OR) for the 17 studies examining postnatal antibiotic exposure was 1.41 [95% confidence interval (CI) 1.30-1.53]. The pooled OR for the 10 longitudinal studies was 1.40 (95% CI 1.19-1.64), compared with a pooled OR of 1.43 (95% CI 1.36-1.51) for the seven cross-sectional studies. There was a significant dose-response association, suggesting a 7% increase in the risk of eczema for each additional antibiotic course received during the first year of life [pooled OR 1.07 (95% CI 1.02-1.11)]. Finally, the pooled OR for the four studies relating to antenatal exposure was 1.30 (95% CI 0.86-1.95). We conclude that exposure to antibiotics in the first year of life, but not prenatally, is more common in children with eczema.


Asunto(s)
Antibacterianos/efectos adversos , Eccema/inducido químicamente , Adolescente , Niño , Preescolar , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Lactante , Estudios Observacionales como Asunto , Embarazo , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Factores de Riesgo , Adulto Joven
13.
Ultrasound Obstet Gynecol ; 41(2): 198-203, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22605519

RESUMEN

OBJECTIVES: To prospectively validate the use of fractional limb volume measurements for estimated fetal weight (EFW) during the second and third trimesters of pregnancy and to summarize the medical literature regarding application of fractional limb volume for fetal weight estimation. METHODS: One hundred and sixty-four women prospectively underwent three-dimensional ultrasonography within 4 days of delivery. Birth weights (BWs) ranged from 390 to 5426 g. Fetal measurements were extracted using volume datasets for biparietal diameter, abdominal circumference, femur diaphysis length, fractional arm volume and fractional thigh volume. Fractional limb volumes were manually traced from a central portion of the humerus or femur diaphysis. Mean percentage differences and SDs of the percentage differences were calculated for EFW. The proportion of newborns with EFW within 5 or 10% of BW were compared with an estimate obtained using a Hadlock formula that was modified using model coefficients from the same local population sample. RESULTS: Ultrasound scans were performed between 21.7 and 42 weeks' menstrual age. Optimal model performance (1.9 ± 6.6%) resulted from using a combination of biparietal diameter, abdominal circumference and fractional thigh volume. The precision of this model was superior to results obtained using a modified Hadlock model (1.1 ± 8.4%), although accuracy of these predictions was slightly decreased for female infants. For all fetuses, the prediction model that incorporated fractional thigh volume correctly classified a greater proportion of EFW within 5% (55.1 vs 43.7%; P = 0.03) or 10% (86.5 vs 75.9%; P < 0.05) of BW when compared with the modified Hadlock model. CONCLUSIONS: Fractional thigh volume can be added to two-dimensional sonographic measurements of the head and trunk to improve the precision of fetal weight estimation. This approach permits the inclusion of soft tissue development as part of a weight estimation procedure for the assessment of generalized fetal nutritional status.


Asunto(s)
Brazo/embriología , Peso Fetal/fisiología , Muslo/embriología , Adulto , Estudios Transversales , Femenino , Edad Gestacional , Humanos , Imagenología Tridimensional , Tamaño de los Órganos , Embarazo , Segundo Trimestre del Embarazo , Tercer Trimestre del Embarazo , Estudios Prospectivos , Ultrasonografía Prenatal/métodos
14.
Ultrasound Obstet Gynecol ; 41(2): 190-7, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22744761

RESUMEN

OBJECTIVE: To evaluate the reproducibility of regional apparent diffusion coefficient (ADC) measurements of the normal fetal brain in the second and third trimesters of pregnancy. METHODS: Fifty normal singleton fetuses from healthy pregnant women between 19 and 37 weeks' gestation were studied without sedation. Single-shot diffusion-weighted images of the fetal brain were obtained using a 1.5-Tesla magnetic resonance scanner and a six-channel body array coil. ADC maps were created using 0 and 1000 b-values along three orthogonal directions. Two examiners independently measured ADC values in the cerebellar hemispheres (CH), pons, thalamus, basal ganglia (BG), centrum semiovale (CSO), and frontal (FWM), parietal (PWM), temporal (TWM) and occipital (OWM) white matter. Correlation between ADC values and menstrual age was assessed by linear regression analysis. The bias and agreement of ADC measurements were determined using Bland-Altman plots. RESULTS: ADC values either remained constant (BG, FWM, PWM, TWM, OWM, CSO) or decreased (CH, pons, thalamus) with advancing menstrual age. Mean intraobserver bias for ADC measurements was not significantly different from zero. Small interobserver differences in mean ADC measurements (i.e. a small mean bias) were detected for CH (1.26 ± 0.20 vs 1.20 ± 0.18 µm(2) /ms, P = 0.006), PWM (1.37 ± 0.29 vs 1.33 ± 0.26 µm(2) /ms, P = 0.02) and CSO (1.36 ± 0.29 vs 1.33 ± 0.28 µm(2) /ms, P < 0.0001). Measurement agreement was acceptable. CONCLUSIONS: ADC measurements in normal unsedated fetuses in the second and third trimesters are reproducible except for small differences for PWM, CH and CSO between examiners.


Asunto(s)
Encéfalo/embriología , Feto/anatomía & histología , Encéfalo/anatomía & histología , Imagen de Difusión por Resonancia Magnética , Femenino , Humanos , Embarazo , Segundo Trimestre del Embarazo , Tercer Trimestre del Embarazo , Diagnóstico Prenatal , Reproducibilidad de los Resultados
15.
Ultrasound Obstet Gynecol ; 41(2): 152-61, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23151941

RESUMEN

OBJECTIVE: To evaluate cervical stiffness during pregnancy using ultrasound-derived elastography, a method used to estimate the average tissue displacement (strain) within a defined region of interest when oscillatory compression is applied. METHODS: Strain was calculated in two regions of interest, the endocervical canal and the entire cervix, from three anatomical planes of the cervix: mid-sagittal in the plane used for cervical length measurement and in cross-sectional planes located at the internal and external cervical os. Associations between strain values, method of ascertainment and patient characteristics were assessed using linear mixed models to account for within-subject correlation. Inter-rater agreement in defining the degree of cervical stiffness was evaluated in 120 regions of interest acquired by two operators in 20 patients. RESULTS: A total of 1557 strain estimations were performed in 262 patients at 8-40 weeks of gestation. Adjusting for other sources of variation, (1) cervical tissue strain estimates obtained in the endocervical canal were on average 33% greater than those obtained in the entire cervix; (2) measurements obtained in the cross-sectional plane of the external cervical os and sagittal plane were 45% and 13% greater than those measured in the cross-sectional plane of the internal cervical os, respectively; (3) mean strain rates were 14% and 5% greater among parous women with and without a history of preterm delivery compared with those of nulliparous women, respectively, and were on average 13% greater among women with a cervical length of between 25 and 30 mm compared to those with a cervical length of > 30 mm; and (4) cervical tissue strain was more strongly associated with cervical length than with gestational age. CONCLUSION: Semiquantitative elastography can be employed to evaluate changes in cervical stiffness during pregnancy.


Asunto(s)
Cuello del Útero/fisiología , Embarazo/fisiología , Adolescente , Adulto , Medición de Longitud Cervical/métodos , Cuello del Útero/diagnóstico por imagen , Elasticidad/fisiología , Diagnóstico por Imagen de Elasticidad/métodos , Femenino , Humanos , Variaciones Dependientes del Observador , Paridad , Trimestres del Embarazo , Estrés Fisiológico/fisiología , Ultrasonografía Prenatal/métodos , Adulto Joven
17.
QJM ; 115(6): 374-380, 2022 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-34051098

RESUMEN

BACKGROUND/INTRODUCTION: Cardio-cerebral infarction (CCI), which involves the simultaneous occurrence of acute ischaemic stroke and acute myocardial infarction, has a reported incidence of 0.0009%. Treatment of CCI presents a dilemma to physicians as both conditions are time critical. Despite the need for standardized treatment protocols, published data are sparse. AIM: We aimed to summarize the reported cardio-cerebral infarction cases in the literature. DESIGN: Meta-analysis. METHODS: Four databases, Pubmed, Embase, Scopus and Google Scholar were searched until 25 August 2020. A title and abstract sieve, full-text review and extraction of data were conducted independently by three authors. RESULTS: A total of 44 cases of CCI were identified from 37 case reports and series; 15 patients (34.1%) were treated using percutaneous coronary intervention (PCI) with stent, 8 patients (18.2%) were treated with a PCI without stent, 10 patients (22.7%) were treated via a cerebral vessel thrombectomy and 8 patients (18.2%) were treated via a thrombectomy of a coronary vessel. For medications, 20 patients (45.5%) were treated with thrombolytics, 10 patients (22.7%) were treated with anticoagulants, 8 patients (18.2%) were treated with antiplatelets and 11 patients (25.0%) were treated with anticoagulants and antiplatelets. Of 44 patients, 10 patients died, and 9 of those were due to cardiac causes. Among the 44 patients, days to death was observed to be a median of 2.0 days (interquartile range (IQR): 1.5, 4.0). The modified Rankin Score was measured in nine patients, with a median score of 2.0 (IQR: 1.0, 2.5) being reported. DISCUSSION/CONCLUSION: The condition of CCI has substantial morbidity and mortality, and further studies are needed to examine the optimal diagnostic and treatment strategies of these patients.


Asunto(s)
Isquemia Encefálica , Intervención Coronaria Percutánea , Accidente Cerebrovascular , Anticoagulantes/uso terapéutico , Isquemia Encefálica/complicaciones , Infarto Cerebral/etiología , Infarto Cerebral/terapia , Humanos , Intervención Coronaria Percutánea/efectos adversos , Accidente Cerebrovascular/etiología , Resultado del Tratamiento
18.
QJM ; 115(1): 7-11, 2022 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-32810234

RESUMEN

BACKGROUND: Transient hyperglycaemia in the context of illness with or without known diabetes has been termed as 'stress hyperglycaemia'. Stress hyperglycaemia can result in poor functional outcomes in patients with acute ischaemic stroke (AIS) who underwent mechanical thrombectomy. We investigated the association between stress hyperglycaemia and clinical outcomes in AIS patients undergoing intravenous thrombolysis (IVT). METHODS: We examined 666 consecutive patients with AIS who underwent IVT from 2006 to 2018. All patients had a glycated haemoglobin level (HbA1c) and fasting venous blood glucose measured within 24 h of admission. Stress hyperglycaemia ratio (SHR) was defined as the ratio of the fasting glucose to the HbA1c. Univariate and multivariate analyses were employed to identify predictors of poor functional outcomes (modified Rankin Scale 3-6 at 3 months) after IVT. RESULTS: Three-hundred and sixty-one patients (54.2%) had good functional outcomes. These patients tended to be younger (60.7 ± 12.7 vs. 70 ± 14.4 years, P < 0.001), male (70.7% vs. 51.5%, P < 0.001), had lower prevalence of atrial fibrillation (13.0% vs. 20.7%, P = 0.008) and lower SHR (0.88 ± 0.20 vs. 0.99 ± 26, P < 0.001). Patients with high SHR (≥0.97) were slightly older than those with low SHR (<0.97) and were more likely to have diabetes mellitus. On multivariate analysis, higher SHR was independently associated with poor functional outcomes (adjusted odds ratio 3.85, 95% confidence interval 1.59-9.09, P = 0.003). CONCLUSION: SHR appears to be an important predictor of functional outcomes in patients with AIS undergoing IVT. This may have important implications on the role of glycaemic control in the acute management of ischaemic stroke.


Asunto(s)
Isquemia Encefálica , Hiperglucemia , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Isquemia Encefálica/complicaciones , Isquemia Encefálica/tratamiento farmacológico , Fibrinolíticos/uso terapéutico , Humanos , Hiperglucemia/tratamiento farmacológico , Masculino , Accidente Cerebrovascular/tratamiento farmacológico , Terapia Trombolítica , Resultado del Tratamiento
19.
Ultrasound Obstet Gynecol ; 37(4): 423-31, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20878671

RESUMEN

OBJECTIVE: To describe a novel and simple algorithm (four-chamber view and 'swing technique' (FAST) echo) for visualization of standard diagnostic planes of fetal echocardiography from dataset volumes obtained with spatiotemporal image correlation (STIC) and applying a new display technology (OmniView). METHODS: We developed an algorithm to image standard fetal echocardiographic planes by drawing four dissecting lines through the longitudinal view of the ductal arch contained in a STIC volume dataset. Three of the lines are locked to provide simultaneous visualization of targeted planes, and the fourth line (unlocked) 'swings' through the ductal arch image (swing technique), providing an infinite number of cardiac planes in sequence. Each line generates the following plane(s): (a) Line 1: three-vessels and trachea view; (b) Line 2: five-chamber view and long-axis view of the aorta (obtained by rotation of the five-chamber view on the y-axis); (c) Line 3: four-chamber view; and (d) 'swing line': three-vessels and trachea view, five-chamber view and/or long-axis view of the aorta, four-chamber view and stomach. The algorithm was then tested in 50 normal hearts in fetuses at 15.3-40 weeks' gestation and visualization rates for cardiac diagnostic planes were calculated. To determine whether the algorithm could identify planes that departed from the normal images, we tested the algorithm in five cases with proven congenital heart defects. RESULTS: In normal cases, the FAST echo algorithm (three locked lines and rotation of the five-chamber view on the y-axis) was able to generate the intended planes (longitudinal view of the ductal arch, pulmonary artery, three-vessels and trachea view, five-chamber view, long-axis view of the aorta, four-chamber view) individually in 100% of cases (except for the three-vessels and trachea view, which was seen in 98% (49/50)) and simultaneously in 98% (49/50). The swing technique was able to generate the three-vessels and trachea view, five-chamber view and/or long-axis view of the aorta, four-chamber view and stomach in 100% of normal cases. In the abnormal cases, the FAST echo algorithm demonstrated the cardiac defects and displayed views that deviated from what was expected from the examination of normal hearts. The swing technique was useful for demonstrating the specific diagnosis due to visualization of an infinite number of cardiac planes in sequence. CONCLUSIONS: This novel and simple algorithm can be used to visualize standard fetal echocardiographic planes in normal fetal hearts. The FAST echo algorithm may simplify examination of the fetal heart and could reduce operator dependency. Using this algorithm, inability to obtain expected views or the appearance of abnormal views in the generated planes should raise the index of suspicion for congenital heart disease.


Asunto(s)
Algoritmos , Ecocardiografía Tetradimensional/normas , Corazón Fetal/diagnóstico por imagen , Ultrasonografía Prenatal/normas , Ecocardiografía Tetradimensional/métodos , Femenino , Edad Gestacional , Cardiopatías Congénitas/diagnóstico por imagen , Humanos , Interpretación de Imagen Asistida por Computador , Variaciones Dependientes del Observador , Embarazo , Valores de Referencia , Reproducibilidad de los Resultados , Ultrasonografía Prenatal/métodos
20.
Ultrasound Obstet Gynecol ; 37(5): 549-56, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-20878672

RESUMEN

OBJECTIVE: To describe a novel and simple technique­simple targeted arterial rendering (STAR)­to visualize the fetal cardiac outflow tracts from dataset volumes obtained with spatiotemporal image correlation (STIC) and applying a new display technology (OmniView). METHODS: We developed a technique to image the outflow tracts by drawing three dissecting lines through the four-chamber view of the heart contained in a STIC volume dataset. Each line generated the following plane: (a) Line 1: ventricular septum en face with both great vessels (pulmonary artery anterior to the aorta); (b) Line 2: pulmonary artery with continuation into the longitudinal view of the ductal arch; and (c) Line 3: long-axis view of the aorta arising from the left ventricle. The pattern formed by all three lines intersecting approximately through the crux of the heart resembles a star. The technique was then tested in 50 normal fetal hearts at 15.3­40.4 weeks' gestation. To determine whether the technique could identify planes that departed from the normal images, we tested the technique in four cases with proven congenital heart defects (ventricular septal defect (VSD), transposition of great vessels, tetralogy of Fallot and pulmonary atresia with intact ventricular septum). RESULTS: The STAR technique was able to generate the intended planes in all 50 normal cases. In the abnormal cases, the STAR technique allowed identification of the VSD, demonstrated great vessel anomalies and displayed views that deviated from what was expected from the examination of normal hearts. CONCLUSIONS: This novel and simple technique can be used to visualize the outflow tracts and ventricular septum en face in normal fetal hearts. Inability to obtain expected views or the appearance of abnormal views in the generated planes should raise the index of suspicion for congenital heart disease involving the great vessels and/or the ventricular septum. The STAR technique may simplify examination of the fetal heart and could reduce operator dependency.


Asunto(s)
Gasto Cardíaco/fisiología , Ecocardiografía Tetradimensional/métodos , Corazón Fetal/diagnóstico por imagen , Cardiopatías Congénitas/diagnóstico por imagen , Arterias/diagnóstico por imagen , Femenino , Corazón Fetal/anomalías , Corazón Fetal/fisiopatología , Cardiopatías Congénitas/fisiopatología , Ventrículos Cardíacos/diagnóstico por imagen , Humanos , Embarazo , Arteria Pulmonar/diagnóstico por imagen , Transposición de los Grandes Vasos/diagnóstico por imagen , Ultrasonografía Prenatal/métodos
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