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1.
Nature ; 594(7864): 508-512, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34163052

RESUMEN

A promising approach to study condensed-matter systems is to simulate them on an engineered quantum platform1-4. However, the accuracy needed to outperform classical methods has not been achieved so far. Here, using 18 superconducting qubits, we provide an experimental blueprint for an accurate condensed-matter simulator and demonstrate how to investigate fundamental electronic properties. We benchmark the underlying method by reconstructing the single-particle band structure of a one-dimensional wire. We demonstrate nearly complete mitigation of decoherence and readout errors, and measure the energy eigenvalues of this wire with an error of approximately 0.01 rad, whereas typical energy scales are of the order of 1 rad. Insight into the fidelity of this algorithm is gained by highlighting the robust properties of a Fourier transform, including the ability to resolve eigenenergies with a statistical uncertainty of 10-4 rad. We also synthesize magnetic flux and disordered local potentials, which are two key tenets of a condensed-matter system. When sweeping the magnetic flux we observe avoided level crossings in the spectrum, providing a detailed fingerprint of the spatial distribution of local disorder. By combining these methods we reconstruct electronic properties of the eigenstates, observing persistent currents and a strong suppression of conductance with added disorder. Our work describes an accurate method for quantum simulation5,6 and paves the way to study new quantum materials with superconducting qubits.

2.
Public Health ; 232: 114-120, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38772199

RESUMEN

OBJECTIVE: To set up and evaluate a new surveillance system for severe acute respiratory infection (SARI) in Scotland. STUDY DESIGN: Cross-sectional study and evaluation of surveillance system. METHODS: The SARI case definition comprised patients aged 16 years or over with an acute respiratory illness presentation requiring testing for influenza and SARS-CoV-2 and hospital admission. Data were collected from SARI cases by research nurses in one tertiary teaching hospital using a bespoke data collection tool from November 2021 to May 2022. Descriptive analyses of SARI cases were carried out. The following attributes of the surveillance system were evaluated according to Centers for Disease Control and Prevention (CDC) guidelines: stability, data quality, timeliness, positive predictive value, representativeness, simplicity, acceptability and flexibility. RESULTS: The final surveillance dataset comprised 1163 records, with cases peaking in ISO week 50 (week ending 19/12/2021). The system produced a stable stream of surveillance data, with the proportion of SARI records with sufficient information for effective surveillance increasing from 65.4% during the first month to 87.0% over time. Similarly, the proportion where data collection was completed promptly was low initially, but increased to 50%-65% during later periods. CONCLUSION: SARI surveillance was successfully established in one hospital, but for a national system, additional sentinel hospital sites across Scotland, with flexibility to ensure consistently high data completeness and timeliness are needed. Data collection should be automated where possible, and demands on clinicians minimised. SARI surveillance should be embedded and resourced as part of a national respiratory surveillance strategy.


Asunto(s)
COVID-19 , Centros de Atención Terciaria , Humanos , Escocia/epidemiología , Estudios Transversales , Femenino , COVID-19/epidemiología , Masculino , Adulto , Persona de Mediana Edad , Anciano , Adolescente , Infecciones del Sistema Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/diagnóstico , SARS-CoV-2 , Adulto Joven , Gripe Humana/epidemiología , Gripe Humana/diagnóstico , Vigilancia de la Población/métodos
3.
Phys Rev Lett ; 130(12): 126802, 2023 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-37027856

RESUMEN

The nature of the antiferromagnetic order in the heavy fermion metal YbRh_{2}Si_{2}, its quantum criticality, and superconductivity, which appears at low mK temperatures, remain open questions. We report measurements of the heat capacity over the wide temperature range 180 µK-80 mK, using current sensing noise thermometry. In zero magnetic field we observe a remarkably sharp heat capacity anomaly at 1.5 mK, which we identify as an electronuclear transition into a state with spatially modulated electronic magnetic order of maximum amplitude 0.1 µ_{B}. We also report results of measurements in magnetic fields in the range 0 to 70 mT, applied perpendicular to the c axis, which show eventual suppression of this order. These results demonstrate a coexistence of a large moment antiferromagnet with putative superconductivity.

4.
Qual Life Res ; 32(7): 1955-1970, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36823327

RESUMEN

PURPOSE: Musculoskeletal complaints (MSCs), a leading contributor to disability worldwide, have a major impact on health-related quality of life (HRQoL). Poor general health related to lifestyle factors such as smoking, alcohol consumption and physical inactivity can lead to a higher risk to suffer MSCs. For minority groups in Suriname such as the Maroons and the Indigenous peoples no research has been conducted regarding prevalence of MSCs, HRQoL and various lifestyle factors. The aims were to determine the prevalence of MSCs and HRQoL in two rural tribal villages in the forested interior of Suriname and to identify various lifestyle factors associated with HRQoL in these communities. METHOD: This was a cross-sectional community-based study using the Community Oriented Program for the Control of Rheumatic Diseases stage 1, phase 1 & 2 methodology in Goejaba, a Maroon village and Galibi, an Indigenous rural village. Sociodemographic data, self-reported comorbidities, past MSCs (for longer than seven days), lifestyle factors including smoking, alcohol use, body mass index (BMI) and physical activity (PA), and HRQoL (using the 36-item Short Form Survey (SF-36)) data were gathered among 153 Indigenous individuals in Galibi, and 516 Maroons in Goejaba. Regression models were constructed to explore associations between presence of MSCs, lifestyle factors and HRQoL. RESULTS: High prevalence rates for past MSCs were reported in Galibi (72.4%) and Goejaba (58.3%). In both communities, respondents with MSCs reported significantly worse HRQoL than persons without MSCs. MSCs and the presence of comorbidities had a strong negative association with HRQoL, whereas PA positively influenced the physical and mental health domains of the SF-36. Smoking, alcohol use and BMI showed no association with HRQoL. CONCLUSIONS: In this first study, a high prevalence for MSCs was reported in an Indigenous and Maroon rural community in Suriname. MSCs and comorbidities had a significant negative impact on HRQoL. PA was associated with higher self-reported HRQoL.


Asunto(s)
Calidad de Vida , Población Rural , Humanos , Calidad de Vida/psicología , Suriname/epidemiología , Prevalencia , Estudios Transversales , Encuestas y Cuestionarios
5.
Cleft Palate Craniofac J ; 60(4): 421-429, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-34939456

RESUMEN

OBJECTIVE: To investigate the prevalence of obstructive sleep apnea syndrome (OSAS) risk and related risk factors among children and adolescents of Hong Kong with cleft lip and/or palate (CL/P). DESIGN: Retrospective survey study adopting three questionnaires, obstructive sleep apnea-18 (OSA-18), pediatric sleep questionnaire-22 (PSQ-22), and modified Epworth Sleepiness Scale (ESS). SETTINGS: Multicenter study in two public hospitals. PATIENTS: A total of 351 Chinese children and adolescents with non-syndromic CL/P (6-18-year-old, 57% males) visited between September 2017 and November 2019, with primary palatal repair surgery done before 3-year-old. MAIN OUTCOME MEASURE: Positive OSAS risk was determined based on cut-off ≥60 for OSA-18, ≥8 for PSQ-22, and >8 for ESS. Age, sex, overweight presence, cleft type, embryonic secondary palate involvement, palatal repair surgery, palatal revision surgery, and orthodontic treatment were analyzed as possible risk factors. RESULTS: A total of 9.5% of patients had positive OSAS risk based on OSA-18, 13.6% based on PSQ-22, and 13.2% according to ESS. A higher prevalence of patients with positive OSAS risk was of younger age (OSA-18, p = .034), had cleft involving embryonic secondary palate (PSQ-22, p = .009), and history of fixed orthodontic treatment (ESS, p = .002). The regression model identified only involvement of embryonic secondary palate as a risk factor (PSQ-22, odds ratio = 3.7, p = .015). CONCLUSIONS: OSAS risk among children and adolescents of Hong Kong with CL/P was 9.5% to 13.6%. Patients at higher risk were those with cleft involving embryonic secondary palate. OSAS risk assessment may be influenced by different aspects of the disease spectrum, and a multimodal approach should be considered for such assessment.


Asunto(s)
Labio Leporino , Fisura del Paladar , Apnea Obstructiva del Sueño , Masculino , Humanos , Niño , Adolescente , Preescolar , Femenino , Labio Leporino/epidemiología , Labio Leporino/cirugía , Labio Leporino/complicaciones , Fisura del Paladar/epidemiología , Fisura del Paladar/cirugía , Fisura del Paladar/complicaciones , Estudios Retrospectivos , Hong Kong/epidemiología , Prevalencia , Apnea Obstructiva del Sueño/etiología , Factores de Riesgo , Encuestas y Cuestionarios
6.
Immunohematology ; 37(1): 33-43, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33962490

RESUMEN

While a variety of therapeutic options continue to emerge for COVID-19 treatment, convalescent plasma (CP) has been used as a possible treatment option early in the pandemic. One of the most significant challenges with CP therapy, however, both when defining its efficacy and implementing its approach clinically, is accurately and efficiently characterizing an otherwise heterogenous therapeutic treatment. Given current limitations, our goal is to leverage a SARS antibody testing platform with a newly developed automated endpoint titer analysis program to rapidly define SARS-CoV-2 antibody levels in CP donors and hospitalized patients. A newly developed antibody detection platform was used to perform a serial dilution enzyme-linked immunosorbent assay (ELISA) for immunoglobulin (Ig)G, IgM, and IgA SARS-CoV-2 antibodies. Data were then analyzed using commercially available software, GraphPad Prism, or a newly developed program developed in Python called TiterScape, to analyze endpoint titers. Endpoint titer calculations and analysis times were then compared between the two analysis approaches. Serial dilution analysis of SARS-CoV-2 antibody levels revealed a high level of heterogeneity between individuals. Commercial platform analysis required significant time for manual data input and extrapolated endpoint titer values when the last serial dilution was above the endpoint cutoff, occasionally producing erroneously high results. By contrast, TiterScape processed 1008 samples for endpoint titer results in roughly 14 minutes compared with the 8 hours required for the commercial software program analysis. Equally important, results generated by TiterScape and Prism were highly similar, with differences averaging 1.26 ± 0.2 percent (mean ± SD). The pandemic has created unprecedented challenges when seeking to accurately test large numbers of individuals for SARS-CoV-2 antibody levels with a rapid turnaround time. ELISA platforms capable of serial dilution analysis coupled with a highly flexible software interface may provide a useful tool when seeking to define endpoint titers in a high-throughput manner. Immunohematology 2021;37:33-43.While a variety of therapeutic options continue to emerge for COVID-19 treatment, convalescent plasma (CP) has been used as a possible treatment option early in the pandemic. One of the most significant challenges with CP therapy, however, both when defining its efficacy and implementing its approach clinically, is accurately and efficiently characterizing an otherwise heterogenous therapeutic treatment. Given current limitations, our goal is to leverage a SARS antibody testing platform with a newly developed automated endpoint titer analysis program to rapidly define SARS-CoV-2 antibody levels in CP donors and hospitalized patients. A newly developed antibody detection platform was used to perform a serial dilution enzyme-linked immunosorbent assay (ELISA) for immunoglobulin (Ig)G, IgM, and IgA SARS-CoV-2 antibodies. Data were then analyzed using commercially available software, GraphPad Prism, or a newly developed program developed in Python called TiterScape, to analyze endpoint titers. Endpoint titer calculations and analysis times were then compared between the two analysis approaches. Serial dilution analysis of SARS-CoV-2 antibody levels revealed a high level of heterogeneity between individuals. Commercial platform analysis required significant time for manual data input and extrapolated endpoint titer values when the last serial dilution was above the endpoint cutoff, occasionally producing erroneously high results. By contrast, TiterScape processed 1008 samples for endpoint titer results in roughly 14 minutes compared with the 8 hours required for the commercial software program analysis. Equally important, results generated by TiterScape and Prism were highly similar, with differences averaging 1.26 ± 0.2 percent (mean ± SD). The pandemic has created unprecedented challenges when seeking to accurately test large numbers of individuals for SARS-CoV-2 antibody levels with a rapid turnaround time. ELISA platforms capable of serial dilution analysis coupled with a highly flexible software interface may provide a useful tool when seeking to define endpoint titers in a high-throughput manner. Immunohematology 2021;37:33­43.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , COVID-19 , Anticuerpos Antivirales , COVID-19/terapia , Ensayo de Inmunoadsorción Enzimática , Humanos , Inmunización Pasiva , SARS-CoV-2 , Sueroterapia para COVID-19
7.
Environ Geochem Health ; 43(11): 4741-4757, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33974199

RESUMEN

In French Guiana were detected high lead (Pb) levels in blood of Amerindian people. Lead exposure is a serious hazard that can affect the cognitive and behavior development. People can be exposed to Pb through occupational and environmental sources. Fingerprinting based on stable Pb isotopes in environmental media is often used to trace natural and anthropogenic sources but is rarely paired with blood data. The objective of this study was to determine the main factors associated with high Blood Lead Levels (BLL). Soil, manioc tubers, food bowls, beverages, wild games, lead pellets and children blood were sampled in small villages along the Oyapock River. children BLL ranged between 5.7 and 35 µg dL-1, all exceeding 5 µg dL-1, the reference value proposed in epidemiologic studies for lead poisoning. Among the different dietary sources, manioc tubers and large game contained elevated Pb concentrations while manioc-based dishes were diluted. The isotopes ratios (207Pb/206Pb and 208Pb/206Pb) of children blood overlapped these of lead shots and meals. These first results confirm for the first time, the diary consumption of manioc-based food as the main contributor to Amerindian children's BLL in French Guiana, but don't exclude the occasional exposure to lead bullets by hunting activities. This is a specific health concern, since previous studies have shown that these same villagers present high levels of mercury (Hg). These communities are indeed subject to a double exposure to neurotoxic metals, Hg and Pb, both through their diet. The farming activity is based on manioc growing, and explaining that this ancestral practice can induce serious health risks for the child's development may seriously affect their food balance and cultural cohesion.


Asunto(s)
Intoxicación por Plomo , Mercurio , Niño , Exposición a Riesgos Ambientales/análisis , Guyana Francesa , Humanos , Plomo/análisis
8.
Lett Appl Microbiol ; 71(3): 294-302, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32358834

RESUMEN

Streptococcus mutans and Candida albicans exhibit a symbiotic relationship to form polymicrobial biofilms that exacerbate oral infections including early-childhood caries, periodontitis and candidiasis. Rhamnus prinoides (gesho) has traditionally been used for the treatment of a variety of illnesses and was recently found to inhibit Gram-positive bacterial biofilm formation. We hypothesized that Rhamnus prinoides extracts have anti-biofilm activity against S. mutans and C. albicans mono- and dual-species biofilms. Ethanol extracts were prepared from gesho stems and leaves; then anti-biofilm activity was assessed using crystal violet, resazurin and XTT staining. Ethanol extracts significantly inhibited Streptococcus mutans and Candida albicans mono-species biofilm formation up to 97 and 75%, respectively. The stem ethanol extract disrupted S. mutans and C. albicans co-culture synergism, with 98% less polymicrobial biofilm formation than the untreated control. Additionally, this extract inhibited planktonic S. mutans cell growth and decreased biofilm polysaccharide production up to 99%. The reduction in polysaccharide production is likely a contributing factor in the anti-biofilm activity of GSE. These findings indicate that gesho or gesho-derived compounds may have potential as additives to oral hygiene products. SIGNIFICANCE AND IMPACT OF THE STUDY: Oral Streptococcus mutans and Candida albicans biofilms are associated with a variety of illnesses. When occurring together, the resulting infections are especially challenging to treat due to enhanced biofilm formation and antibiotic resistance. More therapeutics that can effectively prevent polymicrobial biofilm formation and disrupt interspecies synergism are needed. Rhamnus prinoides ethanol extracts significantly inhibited dual-species biofilm formation and disrupted interspecies synergism.


Asunto(s)
Antibacterianos/farmacología , Biopelículas/crecimiento & desarrollo , Candida albicans/crecimiento & desarrollo , Extractos Vegetales/farmacología , Rhamnus/química , Streptococcus mutans/crecimiento & desarrollo , Candida albicans/efectos de los fármacos , Técnicas de Cocultivo , Caries Dental/microbiología , Caries Dental/prevención & control , Hojas de la Planta , Streptococcus mutans/efectos de los fármacos
9.
Hong Kong Med J ; 26(1): 56-65, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32077861

RESUMEN

OBJECTIVES: Juvenile idiopathic arthritis (JIA) is the most common type of inflammatory arthritis in children. Treatment options have been expanded since the introduction of biologics, which are highly effective. The existing local JIA treatment guideline was published more than a decade ago, when use of biologics was not as common. In this article, we review the latest evidence on using biologics in three JIA subtypes: JIA of polyarticular course (pcJIA), enthesitis-related arthritis (ERA), and psoriatic arthritis (PsA). Based on the latest information, an update on eligibility, response assessment, termination, and safety information for using biologics in these patients was performed. CONSENSUS PROCESS: The JIA Work Group, which consisted of nine paediatricians experienced in managing JIA, was convened in 2016. Publications before July 2017 were screened. Eligible articles were clinical trials, extension studies, systemic reviews, and recommendations from international societies and regulatory agencies about the use of biologics in pcJIA, ERA, and PsA. Evidence extraction, appraisal, and drafting of propositions were performed by two reviewers. Extracted evidence and drafted propositions were presented and discussed at the first two meetings. Overwhelming consensus was obtained at the final meeting in May 2018. Seven practice consensus statements were formulated. Regular review should be performed to keep the practice evidence-based and up-to-date.


Asunto(s)
Antirreumáticos/uso terapéutico , Artritis Juvenil/tratamiento farmacológico , Artritis Psoriásica/tratamiento farmacológico , Productos Biológicos/uso terapéutico , Antirreumáticos/efectos adversos , Productos Biológicos/efectos adversos , Niño , Consenso , Humanos , Guías de Práctica Clínica como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto
10.
Ann Oncol ; 30(1): 76-84, 2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-30395159

RESUMEN

Background: Adjuvant chemoradiation (CRT) is standard for head and neck squamous cell carcinoma (HNSCC) patients with positive margins or extranodal extension (ENE) following surgery. However, emerging evidence suggests the number of positive lymph nodes (LNs) is the dominant determinant of survival in non-oropharyngeal HNSCC and thus may better identify those benefiting from treatment intensification. Patients and methods: Patients from the National Cancer Database diagnosed with non-oropharyngeal HNSCC (oral cavity, larynx, hypopharynx) between 2004 and 2014 and undergoing surgical resection, neck dissection, and postoperative radiotherapy (RT) were included. Multivariable regression with first-order interaction terms was used to model the interaction between postoperative CRT and continuous number of positive LNs with respect to overall survival. Results: In total, 7144 patients met inclusion criteria. In multivariable analysis, increasing number of positive LNs was associated with both increasing mortality (P < 0.001) and increasing benefit from postoperative CRT versus RT alone (interaction P < 0.001). While there was no benefit from postoperative CRT in patients with 0-2 LN+ [hazard ratio (HR) 0.96, 95% confidence interval (CI) 0.86-1.07, P = 0.47], increased benefit was seen in those with 3-5 LN+ (HR 0.84, 95% CI 0.70-1.00, P = 0.05) and those with ≥6 LN+ (HR 0.65, 95% CI 0.51-0.82, P < 0.001) in multivariable models. By contrast, margin status and ENE did not reliably identify patients benefitting from postoperative CRT based on statistical tests of interaction. Even in patients with ENE, positive margins, or both, only those with ≥6 LN+ had improved survival with postoperative CRT. Conclusion: Increasing metastatic nodal burden was associated with increased benefit from CRT compared with RT alone, surpassing conventional high-risk factors in identifying patients benefiting from CRT. Stratification by metastatic LN number may characterize a very-high-risk patient cohort best suited for treatment intensification.


Asunto(s)
Quimioradioterapia Adyuvante/mortalidad , Neoplasias de Cabeza y Cuello/patología , Ganglios Linfáticos/patología , Márgenes de Escisión , Carcinoma de Células Escamosas de Cabeza y Cuello/secundario , Anciano , Terapia Combinada , Femenino , Estudios de Seguimiento , Neoplasias de Cabeza y Cuello/mortalidad , Neoplasias de Cabeza y Cuello/terapia , Humanos , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Pronóstico , Estudios Retrospectivos , Carcinoma de Células Escamosas de Cabeza y Cuello/mortalidad , Carcinoma de Células Escamosas de Cabeza y Cuello/terapia , Tasa de Supervivencia
11.
Magn Reson Med ; 82(5): 1631-1645, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31183892

RESUMEN

PURPOSE: To investigate the potential of continuous radiofrequency (RF) shifting (SWEEP) as a technique for creating densely sampled data while maintaining a stable signal state for dynamic imaging. METHODS: We present a method where a continuous stable state of magnetization is swept smoothly across the anatomy of interest, creating an efficient approach to dense multiple 2D slice imaging. This is achieved by introducing a linear frequency offset to successive RF pulses shifting the excited slice by a fraction of the slice thickness with each successive repeat times (TR). Simulations and in vivo imaging were performed to assess how this affects the measured signal. Free breathing, respiration resolved 4D volumes in fetal/placental imaging is explored as potential application of this method. RESULTS: The SWEEP method maintained a stable signal state over a full acquisition reducing artifacts from unstable magnetization. Simulations demonstrated that the effects of SWEEP on slice profiles was of the same order as that produced by physiological motion observed with conventional methods. Respiration resolved 4D data acquired with this method shows reduced respiration artifacts and resilience to non-rigid and non-cyclic motion. CONCLUSIONS: The SWEEP method is presented as a technique for improved acquisition efficiency of densely sampled short-TR 2D sequences. Using conventional slice excitation the number of RF pulses required to enter a true steady state is excessively high when using short-TR 2D acquisitions, SWEEP circumvents this limitation by creating a stable signal state that is preserved between slices.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Respiración , Artefactos , Mapeo Encefálico/métodos , Simulación por Computador , Femenino , Humanos , Aumento de la Imagen/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Angiografía por Resonancia Magnética , Placenta/irrigación sanguínea , Placenta/diagnóstico por imagen , Embarazo
12.
Anaesthesia ; 74(11): 1389-1396, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31389614

RESUMEN

We evaluated the effect of adrenaline on human skin microcirculation (nutritive and sub-papillary) and systemic cardiovascular variables after it was added to lidocaine in infraclavicular brachial plexus blocks. Twelve healthy, non-smoking male volunteers were included, each attending two study sessions 2 weeks apart, and they were studied using a crossover design. In both sessions, they received an ultrasound-guided infraclavicular brachial plexus block in the non-dominant arm with 0.4 ml.kg-1 lidocaine, 15 mg.ml-1 with or without adrenaline 5 µg.ml-1 . Microcirculation was assessed by laser Doppler fluxmetry (sub-papillary blood flow), capillary video microscopy (nutritive blood flow) and continuous temperature measurements. Heart rate and arterial pressure were recorded continuously and non-invasively. Median (IQR [range]) sub-papillary blood flow increased substantially 30 min after the brachial plexus block, from 8.5 (4.4-13.5 [2.9-28.2]) to 162.7 (111.0-197.8 [9.5-206.7]) arbitrary units with adrenaline (p = 0.017), and from 6.9 (5.3-28.5 [1.8-42.1] to 133.7 (16.5-216.7 [1.0-445.0] arbitrary units without adrenaline (p = 0.036). Nutritive blood flow (functional capillary density, capillaries.mm-2 , measured at the dorsal side of the hand) decreased in the blocked extremity when adrenaline was used as adjuvant, from median (IQR [range]) 45 (36-52 [26-59]) to 38 (29-41 [26-42]), p = 0.028, whereas no significant change occurred without adrenaline. Median finger skin temperature (°C) increased by 44% (data pooled) with no significant differences between the groups. No significant changes were found in the systemic cardiovascular variables with or without adrenaline. We conclude that lidocaine infraclavicular brachial plexus blocks caused an increase in skin sub-papillary blood flow. The addition of adrenaline produced stronger and longer lasting blocks, but decreased the nutritive blood flow.


Asunto(s)
Anestésicos Locales/farmacología , Bloqueo del Plexo Braquial/métodos , Epinefrina/farmacología , Hemodinámica/efectos de los fármacos , Lidocaína/farmacología , Microcirculación/efectos de los fármacos , Agonistas alfa-Adrenérgicos/farmacología , Adulto , Estudios Cruzados , Método Doble Ciego , Quimioterapia Combinada , Hemodinámica/fisiología , Humanos , Masculino , Microcirculación/fisiología , Persona de Mediana Edad , Estudios Prospectivos , Valores de Referencia , Ultrasonografía Intervencional/métodos , Adulto Joven
13.
Clin Radiol ; 73(2): 191-204, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28870430

RESUMEN

Uncommon liver lesions pose a diagnostic challenge because of unfamiliar imaging findings. For simplification, these lesions can be divided into four broad categories based on the dominant imaging feature in each: hypervascular, hypovascular, fat-containing, or cystic lesions. In this review, we profile the radiological features of uncommon liver lesions on multimodality imaging including ultrasound (US), computed tomography (CT), magnetic resonance imaging (MRI), and nuclear medicine.


Asunto(s)
Diagnóstico por Imagen/métodos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/patología , Imagen Multimodal/métodos , Humanos , Hígado/diagnóstico por imagen , Hígado/patología
14.
Hong Kong Med J ; 24(6): 579-583, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30449735

RESUMEN

INTRODUCTION: Patients who sustain an osteoporotic fracture are at increased risk of sustaining further osteoporotic fracture. The risk can be reduced by prescription of anti-osteoporosis medication. The aim of the present study was to determine the current practice in Hong Kong regarding secondary drug prevention of fragility fractures after osteoporotic hip fracture. METHODS: Dispensation of anti-osteoporosis medication records from patients with new fragility hip fractures aged ≥65 years were retrieved using the Hospital Authority Clinical Data Analysis and Reporting System from 2009 to 2012. The intervention rate each year was determined from the percentage of patients receiving anti-osteoporosis medication within 1 year after hip fracture. RESULTS: A total of 15 866 patients with osteoporotic hip fracture who met the criteria were included. The intervention rate differed each year from 2009 to 2012, ranging between 9% and 15%. Orthopaedic surgeons initiated 63% of anti-osteoporosis medication, whereas physicians initiated 37%. The anti-osteoporosis drugs being prescribed included alendronic acid (76%), ibandronic acid (12%), strontium ranelate (5%), and zoledronic acid (4%). CONCLUSION: Most patients with hip fracture remained untreated for 1 year after the osteoporotic hip fracture. The Hospital Authority should allocate more resources to implement a best practice framework for treatment of patients with hip fracture at high risk of secondary fracture.


Asunto(s)
Conservadores de la Densidad Ósea/administración & dosificación , Fracturas de Cadera/prevención & control , Osteoporosis/complicaciones , Fracturas Osteoporóticas/prevención & control , Anciano , Fracturas de Cadera/etiología , Hong Kong , Humanos , Osteoporosis/tratamiento farmacológico , Pautas de la Práctica en Medicina/estadística & datos numéricos , Estudios Retrospectivos , Prevención Secundaria/métodos , Factores de Tiempo
15.
Ann Oncol ; 28(10): 2533-2538, 2017 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-28961834

RESUMEN

Background: Activating events along the PI3K/mTOR pathway are common in head and neck squamous cell carcinomas (HNSCC), and preclinical studies suggest additive or synergistic effects when combining mTORC1 inhibitors with carboplatin and paclitaxel chemotherapy. Patients and methods: In this single-institution phase II study, the combination of temsirolimus 25 mg, carboplatin AUC 1.5, and paclitaxel 80 mg/m2 administered on days 1 and 8 of a 21-day cycle was evaluated in 36 patients with recurrent and/or metastatic (R/M) HNSCC. The primary end point was objective response rate after two cycles of treatment. Secondary end points include the safety and tolerability profile and overall survival. Correlative studies with exome mutational analysis were performed in pre-treatment biopsy samples from 21 patients. Results: Fifteen (41.7%) patients had an objective response, which were all partial responses, and 19 (52.3%) patients had stable disease as best response. The two patients who were designated as 'non-responders' were removed from study prior to two cycles of treatment, but are included in the efficacy and safety analyses. The median duration on study was 5.3 months and the median progression-free survival and overall survival were 5.9 months (95% confidence interval, 4.8-7.1) and 12.8 months (95% confidence interval, 9.8-15.8), respectively. The most common grade 3 and 4 adverse events were hematologic toxicities. Three (3.8%) patients developed neutropenic fever on study. Three of four patients with PIK3CA mutations experienced tumor regressions, and responses were also seen in patients with other genetic alterations in the PI3K/mTOR pathway. Conclusion: The combination of temsirolimus with low-dose weekly carboplatin and paclitaxel appears to have meaningful clinical efficacy in the treatment of R/M HNSCC. This regimen has a relatively high response rate compared to other treatments evaluated in R/M HNSCC, and potential associations with genetic alterations in the PI3K/mTOR pathway should be further explored.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Carcinoma de Células Escamosas/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Carboplatino/administración & dosificación , Carcinoma de Células Escamosas/patología , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Neoplasias de Cabeza y Cuello/patología , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia/patología , Paclitaxel/administración & dosificación , Sirolimus/administración & dosificación , Sirolimus/análogos & derivados , Carcinoma de Células Escamosas de Cabeza y Cuello
16.
BMC Cancer ; 17(1): 359, 2017 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-28532396

RESUMEN

BACKGROUND: The addition of rituximab (R) to CHOP (cyclophosphamide, doxorubicin, vincristine and prednisone) -like therapy has improved survival in primary mediastinal B-cell lymphoma (PMBCL) patients. However, these results were obtained in young low risk patients and a reevaluation in an unselected patient cohort is warranted. METHODS: In this study, we analyzed 80 PMBCL patients treated with a CHOP-based regimen with and without rituximab. RESULTS: In the non-rituximab cohort 10-year progression free survival (PFS) was 67% and 10-year overall survival (OS) was 72% versus a PFS of 95% and a OS of 92% in the rituximab group, PFS P = 0.001, OS P = 0.023. A subgroup PFS analysis by international prognostic index (IPI) risk revealed that all risk groups benefit from addition of rituximab to induction chemotherapy. In addition, OS probability was higher in the group of non-low risk patients who were treated with rituximab compared to those patients who did not receive rituximab (P = 0.035). In multivariate analysis, only addition of rituximab to induction chemotherapy and reaching complete remission (CR) after first line therapy had a beneficial effect on both PFS and OS, whereas IPI, age, upfront high dose (HD) chemotherapy/autologous blood stem cell transplantation (ABSCT) and rituximab maintenance had no impact on survival. CONCLUSIONS: Our data demonstrate a survival benefit in unselected PMBCL patients treated with CHOP-like induction regimen and additional rituximab independently of the IPI risk score.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Neoplasias del Mediastino/tratamiento farmacológico , Adolescente , Adulto , Anciano , Ciclofosfamida/uso terapéutico , Supervivencia sin Enfermedad , Doxorrubicina/uso terapéutico , Femenino , Humanos , Estimación de Kaplan-Meier , Linfoma de Células B Grandes Difuso/mortalidad , Masculino , Neoplasias del Mediastino/mortalidad , Persona de Mediana Edad , Prednisolona/uso terapéutico , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Rituximab/administración & dosificación , Resultado del Tratamiento , Vincristina/uso terapéutico , Adulto Joven
17.
Transfus Med ; 27(1): 36-42, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27726235

RESUMEN

BACKGROUND: Collection of peripheral blood stem cells (PBSCs) for autologous transplantation is a well-established process. As a new generation of leukapheresis (LP) machines has been launched, measures of benchmarking and quality control need to be defined in order to ensure consistent collection performance. OBJECTIVES: The goal of this project was to establish and evaluate a benchmarking system for autologous PBSC collection. METHODS: This retrospective study evaluated PBSC collection data of 198 patients with symptomatic multiple myeloma in first-line therapy who underwent LP in 2013 and 2014 at our institution. Half the patients in 2014 were assigned randomly to undergo LP with the new Terumo BCT Spectra Optia (Terumo BCT, Garching, Germany), while the COBE Spectra (Terumo BCT) was used in all other cases. In 2014, we implemented a previously described formula for predicting daily CD34+ cell collection. As a benchmark, we developed the performance ratio: collected/predicted CD34+ cells. RESULTS: There was no significant difference in the number of collected CD34+ cells, the collection efficiency (collected/processed CD34+ cells) and performance ratio between the two collection devices and between LP procedures in 2013 and 2014. CONCLUSIONS: We present a comprehensive benchmarking tool that is easy to implement, requires minimal expense and allows specific adjustment of LP parameters for optimisation of LP performance. With this approach, we could confirm the equal efficiency of the two compared apheresis systems.


Asunto(s)
Separación Celular , Mieloma Múltiple/sangre , Mieloma Múltiple/terapia , Trasplante de Células Madre de Sangre Periférica , Células Madre de Sangre Periférica , Adulto , Anciano , Autoinjertos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
18.
Hong Kong Med J ; 23(1): 63-6, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27966433

RESUMEN

INTRODUCTION: International clinical guidelines recommend early surgical treatment for geriatric patients with hip fracture. There are, however, few data concerning the operative outcome of centenarians. This study aimed to report the epidemiology of hip fracture and postoperative mortality rate, and to discuss whether operation is justified in centenarians in Hong Kong. METHODS: This observational study was carried out in all public hospitals of Hong Kong. All patients aged 100 years or above who underwent hip fracture surgery in any public hospital between 1 January 2010 and 31 December 2013 were included. Their postoperative mean and median survival time was recorded. RESULTS: Of 114 centenarians, 96 (84%) were female. The age of patients ranged from 100 to 109 years, with the largest number (44%) aged 100 years. The follow-up interval ranged from 5 to 1619 days (median, 412 days; interquartile range, 683 days). The 1-month, 6-month, and 1-year mortalities were 8%, 25%, and 37%, respectively. By Kaplan-Meier analysis, the postoperative mean survival was 2 years 2 months (95% confidence interval, 680-936 days) and the median survival time was 2 years (interquartile range, 1234 days). CONCLUSION: The 1-year mortality among Hong Kong centenarians with hip fracture was 37%, which is lower than the 41.1% in the general centenarian population in Japan. The median survival time after hip fracture surgery was 2 years, suggesting that surgery even at an extreme age is worthwhile to maintain quality of life. Extreme age should not be a barrier to operative treatment.


Asunto(s)
Fracturas de Cadera/mortalidad , Fracturas de Cadera/cirugía , Distribución por Edad , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Hong Kong/epidemiología , Hospitales Públicos , Humanos , Estimación de Kaplan-Meier , Masculino , Periodo Posoperatorio , Calidad de Vida , Factores de Riesgo , Distribución por Sexo , Factores de Tiempo
19.
Hong Kong Med J ; 23(4): 374-80, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28655864

RESUMEN

INTRODUCTION: Studies have shown that early surgery reduces hospital and 1-year mortality in elderly patients with hip fracture, but no major study has examined such relationship in Hong Kong. This study aimed to explore the relationship of early surgery and mortality in a Chinese elderly population with hip fracture. METHODS: This observational study included patients attending public hospitals in Hong Kong. All patients who underwent surgery for geriatric hip fracture in public hospitals from January 2000 to December 2011 were studied. Data were retrieved and collected from the Clinical Data Analysis and Reporting System of the Hospital Authority. Patients were divided into three groups according to timing of surgery: early (0-2 days after admission), delayed (3-4 days after admission), and late (≥5 days after admission) groups. Based on the date of death, we analysed 30-day and 1-year mortality, regardless of cause of death. Comparison of mortality rates was also made between the period before and after implementation of Key Performance Indicator formulated by the Hospital Authority. RESULTS: The overall 1-year mortality rate was 16.8%. The relative risks of 1-year mortality were 1.21 and 1.52 when the delayed and late groups were compared with the early group, respectively. The hazard ratios of long-term mortality were 1.16 (95% confidence interval, 1.13-1.20) and 1.37 (1.33-1.41), respectively for the same comparison. CONCLUSION: Prevalence of geriatric hip fracture will continue to rise and further increase the burden on our health care system. After implementation of Key Performance Indicator, most elderly patients with hip fracture underwent surgery within 2 days provided they were medically fit. Early surgery can reduce both short-term and long-term mortality. Setting up a fragility fracture registry would be beneficial for further studies.


Asunto(s)
Fracturas de Cadera/mortalidad , Procedimientos Ortopédicos/mortalidad , Tiempo de Tratamiento/estadística & datos numéricos , Factores de Edad , Anciano , Anciano de 80 o más Años , Femenino , Fracturas de Cadera/cirugía , Hong Kong/epidemiología , Hospitalización/estadística & datos numéricos , Humanos , Masculino , Procedimientos Ortopédicos/métodos , Modelos de Riesgos Proporcionales , Factores de Riesgo , Factores de Tiempo
20.
J Orthod ; 44(2): 97-104, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28387601

RESUMEN

OBJECTIVES: (1) To undertake a service evaluation of the Index of Orthognathic Functional Treatment Need (IOFTN). (2) To determine its suitability to replace the Index of Orthodontic Treatment Need (IOTN) in the assessment of patients with dentofacial deformity. DESIGN: Laboratory- and questionnaire-based study. SETTING: UK hospital-based orthodontic department. METHODS: Cohen's Kappa was used to assess inter- and intra-operator reliability for the IOTN and the IOFTN against 30 orthognathic patients' models scored to a 'gold standard'. Questionnaires gathered feedback on ease of use of the IOFTN. Change in treatment need status for a further 60 orthognathic patients was estimated utilising the IOTN, the IOFTN and a modified IOTN (mIOTN). RESULTS: Inter-operator agreement with the 'gold standard' for the IOTN and the IOFTN ranged from 0.64-0.90 and 0.61-0.91, respectively. Intra-operator agreement for the IOTN and the IOFTN ranged from 0.46-1.00 to 0.59-0.95, respectively. Mean feedback score was 9.08 out of a maximum score of 10. Overall, 88.9% of patients scored grades 4 or 5 on the IOFTN (IOTN = 87.8%; mIOTN = 77.8%). CONCLUSIONS: The IOFTN is simple and reliable to use. It is an appropriate aid in the prioritisation of surgical patients. Further recommendations are given.


Asunto(s)
Indice de Necesidad de Tratamiento Ortodóncico , Maloclusión , Humanos , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
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