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1.
Nature ; 609(7926): 269-275, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36071190

RESUMEN

Nuclear fusion is one of the most attractive alternatives to carbon-dependent energy sources1. Harnessing energy from nuclear fusion in a large reactor scale, however, still presents many scientific challenges despite the many years of research and steady advances in magnetic confinement approaches. State-of-the-art magnetic fusion devices cannot yet achieve a sustainable fusion performance, which requires a high temperature above 100 million kelvin and sufficient control of instabilities to ensure steady-state operation on the order of tens of seconds2,3. Here we report experiments at the Korea Superconducting Tokamak Advanced Research4 device producing a plasma fusion regime that satisfies most of the above requirements: thanks to abundant fast ions stabilizing the core plasma turbulence, we generate plasmas at a temperature of 100 million kelvin lasting up to 20 seconds without plasma edge instabilities or impurity accumulation. A low plasma density combined with a moderate input power for operation is key to establishing this regime by preserving a high fraction of fast ions. This regime is rarely subject to disruption and can be sustained reliably even without a sophisticated control, and thus represents a promising path towards commercial fusion reactors.

2.
Hong Kong Med J ; 30(1): 16-24, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38226406

RESUMEN

INTRODUCTION: Vaccination is a key strategy to control the coronavirus disease 2019 (COVID-19) pandemic. Safety concerns strongly influence vaccine hesitancy. Disease transmission during pregnancy could exacerbate risks of preterm birth and perinatal mortality. This study examined patterns of vaccination and transmission among pregnant and postnatal women during the fifth wave of COVID-19 in Hong Kong. METHODS: The Antenatal Record System and Clinical Management System of the Hospital Authority was used to retrieve information concerning the demographic characteristics, vaccination history, COVID-19 status, and obstetric outcomes of women who were booked for delivery at Queen Mary Hospital in Hong Kong and had attended the booking antenatal visit from 1 July 2021 to 30 June 2022. RESULTS: Among 2396 women in the cohort, 2006 (83.7%), 1843 (76.9%), and 831 (34.7%) had received the first, second, and third doses of COVID-19 vaccine, respectively. Among 1012 women who had received the second dose, 684 (67.6%) women were overdue for their third dose. There were 265 (11.1%) reported COVID-19 cases. Women aged 20 to 29 years had a low vaccination rate but the highest disease rate (19.1%). The disease rate was more than tenfold higher in women who had no (20.3%) or incomplete (18.8%) vaccination, compared with women who had complete vaccination (2.1%; P<0.001). CONCLUSION: Acceptance of COVID-19 vaccination was low in pregnant women. Urgent measures are needed to promote vaccination among pregnant women before the next wave of COVID-19.


Asunto(s)
COVID-19 , Nacimiento Prematuro , Recién Nacido , Embarazo , Femenino , Humanos , Masculino , Centros de Atención Terciaria , COVID-19/epidemiología , COVID-19/prevención & control , Vacunas contra la COVID-19 , Hong Kong/epidemiología , Vacunación
3.
Clin Exp Dermatol ; 47(4): 700-708, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34762763

RESUMEN

BACKGROUND: Calciphylaxis is a life-threatening cutaneous ulcerative/necrotic disease characterized by vascular calcification/occlusion. It occurs most commonly in end-stage kidney disease (ESKD), known as uraemic calciphylaxis (UC) but can also occur in patients with chronic kidney disease (CKD) and normal kidney function (nonuraemic calciphylaxis; NUC). There are few large series of NUC in the literature. AIM: To compare the clinicopathological features of UC and NUC. METHODS: We retrospectively compared the clinicopathological features of 35 patients with NUC during the period 2010-2020 with those of 53 patients with UC (control group). Cases were classified as NUC in the absence of all of the following: ESKD, significant CKD (defined as serum creatinine > 3 mg/dL or creatinine clearance < 15 mL/min) and acute kidney injury requiring kidney replacement therapy or kidney transplantation. RESULTS: NUC represented 40% of the total cases, and there was a higher number of women (P < 0.01) and a higher median body mass index (P = 0.06) compared with the control UC group. Elevated parathyroid hormone was present in 44% of patients with NUC. Most of the tested patients were positive for lupus anticoagulants (56%). NUC biopsies showed a higher rate of extravascular calcium deposits (73% vs. 47%, P = 0.03). Dermal reactive vascular proliferation was the most common dermal change (32%). CONCLUSIONS: NUC is more common than previously reported and shows a higher predilection for obese postmenopausal women. Undiagnosed hyperparathyroidism shows a possible association with NUC. Lupus anticoagulants were positive in most patients. NUC biopsies are more likely than UC biopsies to display extravascular calcium deposition.


Asunto(s)
Calcifilaxia , Fallo Renal Crónico , Insuficiencia Renal Crónica , Calcifilaxia/diagnóstico , Femenino , Humanos , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/terapia , Insuficiencia Renal Crónica/complicaciones , Estudios Retrospectivos , Factores de Riesgo
4.
Emerg Radiol ; 29(3): 585-593, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35102473

RESUMEN

Chest pain is a common reason for presentation to the emergency department. In many cases, a CTPA or CT thoracic aorta is performed during work up to assess for pulmonary embolism and aortic pathology, critical diagnoses that can be difficult to out rule clinically. However, the causes of chest pain are myriad. It is therefore crucial for the interpreting radiologist to be cognizant of other potential etiologies when interpreting these studies. The purpose of this pictorial essay is to highlight the causes of non-PE or aortic-related chest pain and provide radiologists with a structured approach to interpreting these studies, ensuring a comprehensive search strategy so that important pathologies are not missed.


Asunto(s)
Servicio de Urgencia en Hospital , Embolia Pulmonar , Dolor en el Pecho/diagnóstico por imagen , Humanos , Embolia Pulmonar/diagnóstico por imagen , Radiólogos , Estudios Retrospectivos
5.
Clin Exp Dermatol ; 46(8): 1504-1510, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34081799

RESUMEN

BACKGROUND: During the coronavirus disease 2019 (COVID-19) pandemic, various adverse skin reactions to long-term mask wearing have been reported. AIM: To assess the clinical features of mask-induced dermatoses and to recommend prevention and treatment options. METHODS: From April to August 2020, questionnaires including topics such as demographic information, pre-existing skin disorders, reported mask-related symptoms, daily mask-wearing duration and frequency, types of masks used and whether the participant was a healthcare worker, were distributed to patients in 12 hospitals. Dermatologists assessed skin lesions, confirmed diagnosis and recorded treatments. RESULTS: Itchiness was the most frequent symptom, mostly affecting the cheeks. The most common skin disease was new-onset contact dermatitis (33.94%), followed by new-onset acne (16.97%) and worsening of pre-existing acne (16.97%). Daily wearing of masks was significantly (P = 0.02) associated with new-onset contact dermatitis. More than half of patients with pre-existing skin problems experienced disease worsening while wearing masks. Longer duration of wearing (> 6 h/day, P = 0.04) and use of cotton masks (P < 0.001) significantly increased acne flare-up. Healthcare workers had a higher incidence of skin disease. Skin lesions were generally mild and well tolerated with topical treatment. The study had some limitations: the effect of seasonal characteristics and other risk factors were not assessed, and the patients were visiting dermatological clinics and had interest in their skin status, thus, there may have been selection bias. CONCLUSION: Mask-induced/-triggered dermatoses contribute to increase the dermatological burden during the pandemic.


Asunto(s)
Dermatitis Profesional/etiología , Dermatosis Facial/etiología , Máscaras/efectos adversos , Personal de Hospital , Acné Vulgar/etiología , Adulto , COVID-19/prevención & control , Femenino , Hospitales Universitarios , Humanos , Masculino , Persona de Mediana Edad , Pandemias/prevención & control , Prurito/etiología , República de Corea , SARS-CoV-2 , Centros de Atención Terciaria
6.
Hong Kong Med J ; 27(6): 399-404, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34949729

RESUMEN

INTRODUCTION: Heavy menstrual bleeding is a common gynaecological problem, but some women may prefer not to articulate their menstrual problems. The objective of this study was to evaluate the usefulness and acceptability of the Pictorial Blood Loss Assessment Chart (PBAC) as a selfscreening tool in evaluation of menstrual blood loss among Asian women in Hong Kong. METHODS: This prospective cohort study recruited 206 women from the general gynaecology ward and out-patient clinic: 118 had self-perceived heavy menstrual bleeding and 88 had self-perceived normal menstrual flow. Participants were asked to fill in the PBAC for one menstrual cycle. RESULTS: Compared with women who had self-perceived normal menstrual flow, women with self-perceived heavy menstrual bleeding had significantly higher total PBAC scores and numbers of flooding episodes, larger clot sizes and numbers, more days of bleeding, and lower haemoglobin levels. Receiver-operating characteristic curve analysis demonstrated good pairwise associations of self-perceived symptoms with PBAC score and haemoglobin level. CONCLUSIONS: The PBAC can be used to differentiate self-perceived heavy and normal menstrual bleeding in Asian women in Hong Kong. It can also serve as an additional indicator of possible heavy menstrual bleeding to alert women of the need to seek early medical attention.


Asunto(s)
Menorragia , Femenino , Hong Kong , Humanos , Menorragia/diagnóstico , Estudios Prospectivos
7.
J Synchrotron Radiat ; 27(Pt 4): 864-869, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-33565994

RESUMEN

This paper presents the required structure and function of a ring-FEL as a radiation source for extreme ultraviolet radiation lithography (EUVL). A 100 m-long straight section that conducts an extremely low emittance beam from a fourth-generation storage ring can increase the average power at 13.5 nm wavelength to up to 1 kW without degrading the beam in the rest of the ring. Here, simulation results for a ring-FEL as a EUVL source are described.

8.
Br J Dermatol ; 183(6): 1065-1072, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32163589

RESUMEN

BACKGROUND: Valid patient-reported outcome (PRO) measures are required to evaluate alopecia areata (AA) treatments. OBJECTIVES: To develop a content-valid and clinically meaningful PRO measure to assess AA scalp hair loss with scores comparable with the five-response-level Alopecia Areata Investigator Global Assessment (AA-IGA™). METHODS: A draft PRO measure was developed based on input from 10 clinical experts in AA. The PRO measure was cognitively debriefed, modified and finalized through two rounds of qualitative semistructured interviews with patients with AA who had experienced ≥ 50% scalp hair loss. Data were thematically analysed. RESULTS: Adults (round 1: n = 25; round 2: n = 15) and adolescents aged 15-17 years (round 1: n = 5) in North America participated. All patients named scalp hair loss as a key AA sign or symptom. Patients demonstrated the ability to self-report their current amount of scalp hair using percentages. In round 1 not all patients interpreted the measurement concept consistently; therefore, the PRO was modified to clarify the measurement concept to improve usability. Following modifications, patients in round 2 responded without difficulty to the PRO measure. Patients confirmed that they could use the five-level response scale to rate their scalp hair loss: no missing hair, 0%; limited, 1-20%; moderate, 21-49%; large, 50-94%; nearly all or all, 95-100%. Almost all patients deemed hair regrowth resulting in ≤ 20% scalp hair loss a treatment success. CONCLUSIONS: The Scalp Hair Assessment PRO™ is a content-valid, clinically meaningful assessment of distinct gradations of scalp hair loss for evaluating AA treatment for patients with ≥ 50% hair loss at baseline.


Asunto(s)
Alopecia Areata , Adolescente , Adulto , Alopecia , Alopecia Areata/diagnóstico , Cabello , Humanos , América del Norte , Medición de Resultados Informados por el Paciente , Cuero Cabelludo
9.
Br J Dermatol ; 183(4): 702-709, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-31970750

RESUMEN

BACKGROUND: Content-valid and clinically meaningful instruments are required to evaluate outcomes of therapeutic interventions in alopecia areata (AA). OBJECTIVES: To develop an Investigator's Global Assessment (IGA) to interpret treatment response in AA treatment studies. METHODS: Qualitative interviews were conducted in the USA with expert dermatologists and with patients with AA who had experienced ≥ 50% scalp-hair loss. Thematic data analysis identified critical outcomes and evaluated the content validity of the new IGA. RESULTS: Expert clinicians (n = 10) judged AA treatment success by the amount of scalp-hair growth (median 80% scalp hair). Adult (n = 25) and adolescent (n = 5) patients participated. Scalp-hair loss was the most bothersome AA sign/symptom for most patients. Perceived treatment success - short of 100% scalp hair - was the presence of ~ 70-90% scalp hair (median 80%). Using additional clinician and patient insights, the Alopecia Areata Investigator Global Assessment (AA-IGA™) was developed. This clinician-reported outcome assessment is an ordinal, static measure comprising five severity categories of scalp-hair loss. Nearly all clinicians and patients in this study agreed that, for patients with ≥ 50% scalp-hair loss, successful treatment would be hair regrowth resulting in ≤ 20% scalp-hair loss. CONCLUSIONS: We recommend using the Severity of Alopecia Tool to assess the extent (0-100%) of scalp-hair loss. The AA-IGA is a robust ordinal measure providing distinct and clinically meaningful gradations of scalp-hair loss that reflects patients' and expert clinicians' perspectives and treatment expectations. What is already known about this topic? The Severity of Alopecia Tool is widely used to assess the extent of scalp-hair loss in patients with alopecia areata. Guidelines define treatment success as a 50% improvement in scalp hair, and clinical trials have used dynamic thresholds of 50% and 90%. However, there is no clinical consensus on these endpoints, and patient perspectives on treatment success are unknown. What does this study add? Through qualitative interviews with 10 expert dermatologists and 30 patients with alopecia areata who had experienced ≥ 50% scalp-hair loss, we developed the Alopecia Areata Investigator Global Assessment (AA-IGA™) to measure five clinically meaningful gradations of alopecia areata scalp-hair loss that reflects patients' and clinicians' perspectives and expectations of treatment success in alopecia areata treatment studies. What are the clinical implications of this work? The AA-IGA is a robust ordinal measure that can inform clinical evaluation of alopecia areata treatment outcomes. The AA-IGA can be used to determine clinically meaningful treatment success for alopecia areata, with success defined by patients and clinicians as reaching ≤ 20% scalp-hair loss. Linked Comment: Blome. Br J Dermatol 2020; 183:609.


Asunto(s)
Alopecia Areata , Adolescente , Adulto , Alopecia , Alopecia Areata/tratamiento farmacológico , Cabello , Humanos , Cuero Cabelludo
10.
Ultrasound Obstet Gynecol ; 55(3): 303-309, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31325336

RESUMEN

OBJECTIVE: To compare the proportion of women achieving a desired ovarian response following ovarian stimulation when gonadotropin dosing was determined based on antral follicle count (AFC) vs serum anti-Müllerian hormone (AMH) level, in women undergoing in-vitro fertilization (IVF) using the gonadotropin-releasing hormone (GnRH) antagonist protocol. METHODS: This was a randomized double-blind trial carried out in a university-affiliated assisted reproduction unit. A total of 200 women undergoing their first IVF cycle using the GnRH-antagonist protocol between April 2016 and February 2018 were randomized to determination of gonadotropin dosing based on either AFC or serum AMH level measured in the pretreatment cycle 1 month before the IVF cycle. Patients underwent IVF as per our center's standard protocol. The proportion of subjects achieving a desired ovarian response, defined as retrieval of six to 14 oocytes, was compared between the two study arms. Subgroup analysis of patients with baseline AFC > 5 and those with baseline AFC ≤ 5 was performed. Concordance in AFC and AMH categorization between the pretreatment cycle and the ovarian-stimulation cycle was assessed using Cohen's kappa (κ). RESULTS: There was no significant difference in the proportion of patients achieving a desired ovarian response between the AFC (54%) and AMH (49%) groups (P = 0.479). The median number of oocytes retrieved was nine vs seven (P = 0.070), and the median follicular output rate was 0.54 vs 0.55 (P = 0.764) in the AFC and AMH groups, respectively. Similar findings were observed on subgroup analysis of subjects with AFC ≤ 5 and AFC > 5 at the start of ovarian stimulation (P > 0.05 for all comparisons). There was moderate concordance between AFC and AMH measured in the pretreatment cycle and the stimulation cycle (κ = 0.478 and 0.587, respectively). CONCLUSION: The proportion of women achieving a desired ovarian response following ovarian stimulation using the GnRH-antagonist protocol is similar when the gonadotropin-dosing algorithm used is based on AFC or serum AMH level. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.


Comparación del recuento de folículos sinusales y el nivel de la hormona antimulleriana en el suero para la determinación de la dosis de gonadotrofina en la fecundación in vitro: ensayo aleatorizado OBJETIVO: Comparar la proporción de mujeres que logran una respuesta ovárica deseada tras la estimulación del ovario cuando se determinó la dosis de gonadotrofina en función del recuento de folículos sinusales (AFC, por sus siglas en inglés) frente al nivel de la hormona antimulleriana (HAM) en el suero, en mujeres que se sometieron a una fecundación in vitro (FIV) mediante el protocolo de antagonistas de la hormona liberadora de gonadotropina (GnRH, por sus siglas en inglés). MÉTODOS: Se trata de un ensayo aleatorizado doble ciego realizado en una unidad de reproducción asistida afiliada a una universidad. Un total de 200 mujeres que se sometieron a su primer ciclo de FIV y utilizaron el protocolo de antagonistas de la GnRH entre abril de 2016 y febrero de 2018 fueron asignadas al azar a la determinación de la dosis de gonadotrofina basada en el nivel de AFC o de HAM en suero, medidos en el ciclo de pretratamiento un mes antes del ciclo de FIV. Las pacientes se sometieron a una FIV según el protocolo estándar de nuestro centro. La proporción de mujeres que lograron una respuesta ovárica deseada, definida como la recuperación de seis a 14 ovocitos, se comparó entre las dos ramas del estudio. Se realizó un análisis de subgrupos de las pacientes con AFC de base >5 y de aquellas con AFC de base ≤5. La concordancia en la categorización del AFC y la HAM entre el ciclo de pretratamiento y el ciclo de estimulación ovárica se evaluó utilizando la medida estadística kappa de Cohen (κ). RESULTADOS: No hubo diferencias significativas en la proporción de pacientes que lograron una respuesta ovárica deseada entre los grupos de AFC (54%) y HAM (49%) (P=0,479). La mediana del número de ovocitos recuperados fue de nueve frente a siete (P=0,070), y la mediana de la tasa de producción folicular fue de 0,54 frente a 0,55 (P=0,764) en los grupos AFC y HAM, respectivamente. Se observaron hallazgos similares en el análisis de subgrupos de pacientes con AFC ≤5 y AFC >5 al comienzo de la estimulación ovárica (P>0,05 para todas las comparaciones). Se observó una concordancia moderada entre el AFC y la HAM medidos en el ciclo de pretratamiento y el ciclo de estimulación (κ=0,478 y 0,587, respectivamente). CONCLUSIÓN: La proporción de mujeres que logran una respuesta ovárica deseada después de la estimulación ovárica utilizando el protocolo de antagonistas de la GnRH es similar cuando el algoritmo de dosificación de gonadotrofina utilizado se basa en el nivel del AFC o de la HAM en suero.


Asunto(s)
Hormona Antimülleriana/sangre , Fertilización In Vitro/métodos , Gonadotropinas/administración & dosificación , Antagonistas de Hormonas/administración & dosificación , Folículo Ovárico/crecimiento & desarrollo , Adulto , Algoritmos , Método Doble Ciego , Femenino , Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Humanos , Inducción de la Ovulación/métodos , Embarazo , Resultado del Tratamiento
11.
Proc Natl Acad Sci U S A ; 114(29): 7519-7524, 2017 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-28673975

RESUMEN

Long carrier lifetime is what makes hybrid organic-inorganic perovskites high-performance photovoltaic materials. Several microscopic mechanisms behind the unusually long carrier lifetime have been proposed, such as formation of large polarons, Rashba effect, ferroelectric domains, and photon recycling. Here, we show that the screening of band-edge charge carriers by rotation of organic cation molecules can be a major contribution to the prolonged carrier lifetime. Our results reveal that the band-edge carrier lifetime increases when the system enters from a phase with lower rotational entropy to another phase with higher entropy. These results imply that the recombination of the photoexcited electrons and holes is suppressed by the screening, leading to the formation of polarons and thereby extending the lifetime. Thus, searching for organic-inorganic perovskites with high rotational entropy over a wide range of temperature may be a key to achieve superior solar cell performance.


Asunto(s)
Compuestos de Calcio/química , Yoduros/química , Metales Pesados/química , Óxidos/química , Fotoquímica , Titanio/química , Electrones , Luminiscencia , Neutrones , Energía Solar , Luz Solar , Temperatura
12.
Phys Rev Lett ; 122(2): 021802, 2019 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-30720307

RESUMEN

A search for the rare decay K_{L}→π^{0}νν[over ¯] was performed. With the data collected in 2015, corresponding to 2.2×10^{19} protons on target, a single event sensitivity of (1.30±0.01_{stat}±0.14_{syst})×10^{-9} was achieved and no candidate events were observed. We set an upper limit of 3.0×10^{-9} for the branching fraction of K_{L}→π^{0}νν[over ¯] at the 90% confidence level (C.L.), which improved the previous limit by almost an order of magnitude. An upper limit for K_{L}→π^{0}X^{0} was also set as 2.4×10^{-9} at the 90% C.L., where X^{0} is an invisible boson with a mass of 135 MeV/c^{2}.

13.
Rhinology ; 57(6): 411-419, 2019 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-31403138

RESUMEN

BACKGROUND: To estimate the rate of revision surgery after previous adenoidectomy in children and to compare the rate of revision adenoidectomy in children with different conditions and by using different surgical techniques. METHODOLOGY: The study protocol was registered on PROSPERO (CRD42018107877). Two authors independently searched databases, specifically PubMed, MEDLINE, EMBASE, and the Cochrane Review database. The keywords used were "adenoids","adenoidectomy","reoperation","revision"and "regrowth". The revision rate was pooled using a random-effect model. Subgroup analyses were conducted for children based on different settings, countries, risks of bias, and surgical techniques. RESULTS: A total 16 studies with 95 727 children were analyzed (mean age: 4.69 (1.62) years; 60% boys; sample size: 5983 patients). Five studies had a low risk of bias, 10 studies had a moderate risk of bias, and one study had a high risk of bias. The rate of revision adenoidectomy was 1.9%. Ages at initial surgery and follow-up were not significantly associated with revision surgeries. The revision rate was not significantly different in children receiving surgeries in different settings (single center vs multicenter vs population-based, country (non-United States vs United States, and risk of bias. Moreover, surgical techniques, such as curettage, suction cautery, microdebridement, and coblation did not significantly affect revision rates in children who received adenoidectomy. CONCLUSIONS: Revision surgery was undertaken with a frequency of 1.9% in children who underwent adenoidectomy. A lack of strong evidence exists to correlate surgical techniques with revision rate in pediatric adenoidectomy.


Asunto(s)
Adenoidectomía/métodos , Tonsila Faríngea/cirugía , Enfermedades Faríngeas/cirugía , Niño , Preescolar , Femenino , Humanos , Masculino , Reoperación
14.
Ann Oncol ; 29(9): 1972-1979, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-30016391

RESUMEN

Background: Concurrent chemoradiotherapy (CCRT) is superior to radiotherapy alone for treating locoregionally advanced nasopharyngeal carcinoma (NPC). Whether adding induction chemotherapy (IC) further improves the outcome warrants investigation. Patients and methods: This open-label multicenter phase III trial was conducted at 11 institutions in Taiwan. Patients with stage IVA or IVB NPC were randomized to receive IC followed by CCRT (I-CCRT) or CCRT alone. Patients in the I-CCRT arm received three cycles of mitomycin C, epirubicin, cisplatin, and 5-fluorouracil/leucovorin (MEPFL). All patients received 30 mg/m2 cisplatin weekly during radiotherapy, which was delivered as 1.8-2.2 Gy per fraction with five daily fractions per week, to a total dose of 70 Gy or greater to the primary tumor and 66-70 Gy to the involved neck. The primary end point was disease-free survival (DFS). Results: In this study, 240 and 239 patients were randomized to CCRT and I-CCRT arm, respectively. The most prominent toxicities of induction were leukopenia (grade 3 and 4: 47% and 12%) and thrombocytopenia (grade 3 and 4: 24% and 3%). During radiotherapy, severe mucositis was the major side-effect in both arms; an increased number of patients in the I-CCRT arm had myelosuppression; hence, discontinuation of weekly cisplatin was more common. After a median follow-up of 72.0 months, the I-CCRT arm had significantly higher DFS than that of the CCRT arm [5-year rate 61% versus 50%; hazard ratio=0.739, 95% confidence interval (CI)=0.565-0.965; P = 0.0264], after stratified for N3b and LDH, and adjusted for T stage. Conclusion: Induction with MEPFL before CCRT was tolerable and significantly improved the DFS of patients with stage IVA and IVB NPC though overall survival not improved. Clinical trial information: NCT00201396.


Asunto(s)
Quimioradioterapia/métodos , Quimioterapia de Inducción/métodos , Carcinoma Nasofaríngeo/terapia , Neoplasias Nasofaríngeas/terapia , Radioterapia de Intensidad Modulada/métodos , Adolescente , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Quimioradioterapia/efectos adversos , Supervivencia sin Enfermedad , Fraccionamiento de la Dosis de Radiación , Femenino , Estudios de Seguimiento , Humanos , Quimioterapia de Inducción/efectos adversos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Carcinoma Nasofaríngeo/mortalidad , Carcinoma Nasofaríngeo/patología , Neoplasias Nasofaríngeas/mortalidad , Neoplasias Nasofaríngeas/patología , Estadificación de Neoplasias , Radioterapia de Intensidad Modulada/efectos adversos , Taiwán/epidemiología , Adulto Joven
15.
Eur J Clin Microbiol Infect Dis ; 37(2): 305-311, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29177611

RESUMEN

The efficacy of empirical non-carbapenem antibiotics for extended-spectrum beta-lactamase-producing Enterobacteriaceae bacteremia (ESBL-B) is still inconclusive. We conducted a multicenter retrospective cohort study to evaluate the efficacy of empirical non-carbapenem antibiotics for treating ESBL-B. Electronic medical records of individuals who were diagnosed with ESBL-B were reviewed between January 2010 and December 2014 at four university hospitals in Korea. Patients were classified into non-carbapenem and carbapenem groups according to the empirical antibiotic regimen. Patients treated with appropriate empirical antibiotics and who subsequently received carbapenems as definitive therapy were included in the analysis. The inverse probability of treatment weights, a statistical method that adjusts baseline statistics by giving weights based on propensity score, was used. During the study period, 232 adequately treated patients with ESBL-B were included in the analysis: 49 patients in the non-carbapenem group and 183 in the carbapenem group. The baseline characteristics and severity of infection were similar after propensity score weighting. The 30-day mortality rates for the two groups were not statistically significantly different (non-carbapenems 6.3% and carbapenems 11.4%; P = 0.42). In a multivariate analysis, empirical treatment with non-carbapenem antibiotics was not associated with 30-day all-cause mortality (HR 1.02, 95% CI 0.99-1.06, P = 0.14). In a subgroup analysis, empirical treatment with piperacillin-tazobactam was also not associated with 30-day all-cause mortality (HR 1.21, 95% CI 0.37-4.00, P = 0.75). Appropriate non-carbapenems were not inferior to carbapenems as initial empirical therapy for ESBL-B.


Asunto(s)
Antibacterianos/uso terapéutico , Bacteriemia/tratamiento farmacológico , Enterobacteriaceae Resistentes a los Carbapenémicos/efectos de los fármacos , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Klebsiella/tratamiento farmacológico , Puntaje de Propensión , Anciano , Bacteriemia/microbiología , Bacteriemia/mortalidad , Enterobacteriaceae Resistentes a los Carbapenémicos/aislamiento & purificación , Ciprofloxacina/uso terapéutico , Escherichia coli/efectos de los fármacos , Escherichia coli/aislamiento & purificación , Infecciones por Escherichia coli/microbiología , Femenino , Humanos , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/aislamiento & purificación , Masculino , Meropenem , Persona de Mediana Edad , Ácido Penicilánico/análogos & derivados , Ácido Penicilánico/uso terapéutico , Piperacilina/uso terapéutico , Combinación Piperacilina y Tazobactam , Estudios Retrospectivos , Centros de Atención Terciaria , Tienamicinas/uso terapéutico , Resultado del Tratamiento
16.
Public Health ; 165: 16-25, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30347314

RESUMEN

OBJECTIVES: This study aimed to determine the relative risks of addiction to the Internet, online gaming and online social networking of college students in six Asian countries/regions (Singapore, Hong Kong [HK]/Macau, China, South Korea, Taiwan and Japan) compared with students in the United States (US). It also explored the relative risks of depression and anxiety symptoms among students with Internet-related addictions from these countries/regions. STUDY DESIGN: This is a cross-sectional survey. METHODS: A convenience sample of 8067 college students aged between 18 and 30 years was recruited from seven countries/regions. Students completed a survey about their use of the Internet, online gaming and online social networking as well as the presence of depression and anxiety symptoms. RESULTS: For all students, the overall prevalence rates were 8.9% for Internet use addiction, 19.0% for online gaming addiction and 33.1% for online social networking addiction. Compared with the US students, Asian students showed higher risks of online social networking addiction but displayed lower risks of online gaming addiction (with the exception of students from HK/Macau). Chinese and Japanese students also showed higher risks of Internet addiction compared with the US students. In general, addicted Asian students were at higher risks of depression than the addicted US students, especially among Asian students who were addicted to online gaming. Addicted Asian students were at lower risks of anxiety than the addicted US students, especially among Asian students who were addicted to online social networking, and addicted students from HK/Macau and Japan were more likely to have higher relative risks of depression. CONCLUSIONS: There are country/regional differences in the risks of Internet-related addictions and psychiatric symptoms. It is suggested that country/region-specific health education programmes regarding Internet-related addictions are warranted to maximise the efficiency of prevention and intervention. These programmes should attempt to tackle not only problematic Internet-related behaviours but also mood disturbances among college students.


Asunto(s)
Ansiedad/epidemiología , Conducta Adictiva/epidemiología , Depresión/epidemiología , Internet/estadística & datos numéricos , Red Social , Estudiantes/psicología , Juegos de Video/estadística & datos numéricos , Adolescente , Adulto , Asia/epidemiología , Comparación Transcultural , Estudios Transversales , Femenino , Humanos , Masculino , Riesgo , Estudiantes/estadística & datos numéricos , Encuestas y Cuestionarios , Estados Unidos/epidemiología , Universidades , Adulto Joven
17.
Phys Rev Lett ; 118(20): 205501, 2017 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-28581808

RESUMEN

Multielement solid solution alloys are intrinsically disordered on the atomic scale, and many of their advanced properties originate from the local structural characteristics. The local structure of a NiCoCr solid solution alloy is measured with x-ray or neutron total scattering and extended x-ray absorption fine structure (EXAFS) techniques. The atomic pair distribution function analysis does not exhibit an observable structural distortion. However, an EXAFS analysis suggests that the Cr atoms are favorably bonded with Ni and Co in the solid solution alloys. This short-range order (SRO) may make an important contribution to the low values of the electrical and thermal conductivities of the Cr-alloyed solid solutions. In addition, an EXAFS analysis of Ni ion irradiated samples reveals that the degree of SRO in NiCoCr alloys is enhanced after irradiation.

18.
Eur J Clin Microbiol Infect Dis ; 36(11): 2093-2100, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28643188

RESUMEN

Despite a significant increase of bloodstream infection caused by extended-spectrum-ß-lactamase (ESBL)-producing Enterobacteriaceae in the community-setting, information regarding clinical outcomes of inappropriate empiric therapy (IAT) in patients with those infections is limited. A multicenter-retrospective cohort study was conducted in four hospitals. A total of 249 adults were identified to have community-onset bacteremia caused by ESBL-producing Escherichia coli and Klebsiella pneumoniae, and definitively treated with carbapenems. According to the appropriateness of empiric therapy, individuals were divided into an appropriate empiric therapy (AT) group (n = 106) and IAT group (n = 143). Patients who received AT showed more severe underlying conditions including underlying solid cancer, healthcare-association and intensive care unit (ICU) care, compared to the IAT group. Primary bacteremia was more commonly found in the AT group than in the IAT group, while urinary tract infection predominated more frequently in the IAT group than in the AT group. Multivariate analysis using propensity score analysis indicated that inappropriateness of empiric therapy was not an independent risk factor for 30-day death. ICU care, respiratory tract infection and underlying liver, renal and connective tissue diseases were significantly associated with mortality. In patients with bloodstream infections caused by ESBL-producing E. coli and K. pneumoniae in the community-setting, delay in appropriate therapy was not associated with an increased rate of death if the patients were definitively treated with carbapenems.


Asunto(s)
Antibacterianos/uso terapéutico , Bacteriemia/tratamiento farmacológico , Carbapenémicos/uso terapéutico , Infecciones por Escherichia coli/tratamiento farmacológico , Prescripción Inadecuada/efectos adversos , Infecciones por Klebsiella/tratamiento farmacológico , Anciano , Bacteriemia/microbiología , Infecciones Comunitarias Adquiridas/tratamiento farmacológico , Infecciones Comunitarias Adquiridas/microbiología , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Infecciones por Escherichia coli/microbiología , Femenino , Humanos , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/genética , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resistencia betalactámica/genética
19.
Eur J Clin Microbiol Infect Dis ; 36(7): 1091-1096, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28078559

RESUMEN

To evaluate effect of empirical combination of a ß-lactam to vancomycin and vancomycin monotherapy in Staphylococcus aureus bacteremia (MSSA-B), we conducted a retrospective cohort study. Electronic medical records of individuals who were diagnosed with MSSA-B between January 2005 and February 2015 at a tertiary care center were reviewed. Patients were classified into three groups according to empirical antibiotic regimen (BL group, ß-lactam; VAN group, vancomycin; BV group, combination of ß-lactam and vancomycin), and 30-day all-cause mortality of each group was compared. During the study period, 561 patients with MSSA-B were identified. After exclusion of 198 patients (36 with poly-microbial infection, 114 expired within 2 days, and 48 already received parenteral antibiotics) and a matching process, 46 patients for each group were included. Baseline characteristics were similar except for severity and comorbidity scores. The 30-day mortality for all three groups were not significantly different (BL 4.3%, VAN 6.5%, BV 8.7%; P = 0.909). In a multivariate analysis, type of empirical antibiotic regimen was not statistically associated with 30-day all-cause mortality. In comparison with the VAN group, the BV group yielded a HR of 0.579 (95% CI = 0.086-3.890, P = 0.574). Pitt bacteremia score was the only significant factor for mortality. The empirical combination of a ß-lactam to vancomycin was not associated with lower mortality in treating MSSA-B, compared to vancomycin monotherapy.


Asunto(s)
Antibacterianos/administración & dosificación , Bacteriemia/tratamiento farmacológico , Infecciones Estafilocócicas/tratamiento farmacológico , Vancomicina/administración & dosificación , beta-Lactamas/administración & dosificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Bacteriemia/mortalidad , Quimioterapia Combinada/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Infecciones Estafilocócicas/mortalidad , Análisis de Supervivencia , Centros de Atención Terciaria , Resultado del Tratamiento , Adulto Joven
20.
Eur J Clin Microbiol Infect Dis ; 36(11): 2179-2186, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28695355

RESUMEN

To provide optimal cut-off values of anti-Middle East respiratory syndrome coronavirus (MERS-CoV) serologic tests, we evaluated performance of ELISA IgG, ELISA IgA, IFA IgM, and IFA IgG using 138 serum samples of 49 MERS-CoV-infected patients and 219 serum samples of 219 rRT-PCR-negative MERS-CoV-exposed healthcare personnel and patients. The performance analysis was conducted for two different purposes: (1) prediction of neutralization activity in MERS-CoV-infected patients, and (2) epidemiologic surveillance of MERS-CoV infections among MERS-CoV-exposed individuals. To evaluate performance according to serum collection time, we used 'days post onset of illness (dpoi)' and 'days post exposure (dpex)' assessing neutralization activity and infection diagnosis, respectively. Performance of serologic tests improved with delayed sampling time, being maximized after a seroconversion period. In predicting neutralization activity, ELISA IgG tests showed optimal performance using sera collected after 21 dpoi at cut-off values of OD ratio 0.4 (sensitivity 100% and specificity 100%), and ELISA IgA showed optimal performance using sera collected after 14 dpoi at cut-off value of OD ratio 0.2 (sensitivity 85.2% and specificity 100%). In diagnosis of MERS-CoV infection, ELISA IgG exhibited optimal performance using sera collected after 28 dpex, at a cut-off value of OD ratio 0.2 (sensitivity 97.3% and specificity 92.9%). These new breakpoints are markedly lower than previously suggested values (ELISA IgG OD ratio 1.1, sensitivity 34.8% and specificity 100% in the present data set), and the performance data help serologic tests to be practically used in the field of MERS management.


Asunto(s)
Anticuerpos Antivirales/sangre , Infecciones por Coronavirus/diagnóstico , Ensayo de Inmunoadsorción Enzimática/métodos , Coronavirus del Síndrome Respiratorio de Oriente Medio/inmunología , Pruebas Serológicas/métodos , Infecciones por Coronavirus/sangre , Infecciones por Coronavirus/inmunología , Infecciones por Coronavirus/virología , Humanos , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Sensibilidad y Especificidad
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