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1.
Ann Oncol ; 33(12): 1304-1317, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36055464

RESUMO

BACKGROUND: The development of immune checkpoint blockade (ICB) has changed the way we treat various cancers. While ICB produces durable survival benefits in a number of malignancies, a large proportion of treated patients do not derive clinical benefit. Recent clinical profiling studies have shed light on molecular features and mechanisms that modulate response to ICB. Nevertheless, none of these identified molecular features were investigated in large enough cohorts to be of clinical value. MATERIALS AND METHODS: Literature review was carried out to identify relevant studies including clinical dataset of patients treated with ICB [anti-programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1), anti-cytotoxic T-lymphocyte antigen 4 (CTLA-4) or the combination] and available sequencing data. Tumor mutational burden (TMB) and 37 previously reported gene expression (GE) signatures were computed with respect to the original publication. Biomarker association with ICB response (IR) and survival (progression-free survival/overall survival) was investigated separately within each study and combined together for meta-analysis. RESULTS: We carried out a comparative meta-analysis of genomic and transcriptomic biomarkers of IRs in over 3600 patients across 12 tumor types and implemented an open-source web application (predictIO.ca) for exploration. TMB and 21/37 gene signatures were predictive of IRs across tumor types. We next developed a de novo GE signature (PredictIO) from our pan-cancer analysis and demonstrated its superior predictive value over other biomarkers. To identify novel targets, we computed the T-cell dysfunction score for each gene within PredictIO and their ability to predict dual PD-1/CTLA-4 blockade in mice. Two genes, F2RL1 (encoding protease-activated receptor-2) and RBFOX2 (encoding RNA-binding motif protein 9), were concurrently associated with worse ICB clinical outcomes, T-cell dysfunction in ICB-naive patients and resistance to dual PD-1/CTLA-4 blockade in preclinical models. CONCLUSION: Our study highlights the potential of large-scale meta-analyses in identifying novel biomarkers and potential therapeutic targets for cancer immunotherapy.


Assuntos
Neoplasias , Receptor de Morte Celular Programada 1 , Humanos , Camundongos , Animais , Antígeno CTLA-4/genética , Inibidores de Checkpoint Imunológico , Big Data , Antígeno B7-H1 , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/patologia , Biomarcadores Tumorais/genética , Fatores de Processamento de RNA/uso terapêutico , Proteínas Repressoras
2.
Cardiovasc Diabetol ; 21(1): 231, 2022 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-36335340

RESUMO

BACKGROUND: Circulating thrombospondin-2 (TSP2) levels were associated with the development of heart failure (HF) in recent studies. However, these studies included only a minority of patients with type 2 diabetes, which is associated with an increased HF risk. As hyperglycemia induces TSP2 expression and its tissue expression increases in type 2 diabetes, we investigated the prospective association of circulating TSP2 with incident HF hospitalization (HHF), and its associations with longitudinal changes of echocardiographic parameters in type 2 diabetes. METHODS: Baseline serum TSP2 levels were measured in 4949 patients with type 2 diabetes to determine its association with incident HHF using multivariable Cox regression analysis. In the echocardiographic study, baseline serum TSP2 levels were measured in another 146 patients with type 2 diabetes but without cardiovascular diseases who underwent detailed transthoracic echocardiography at baseline and after 1 year. RESULTS: Over a median follow-up of 7.8 years, 330 of 4949 patients (6.7%) developed incident HHF. Baseline serum TSP2 levels were independently associated with the development of HHF (HR 1.31, 95%CI 1.06-1.62, p = 0.014) after adjustments for baseline conventional cardiovascular risk factors, atrial fibrillation, estimated glomerular filtration rate, albuminuria and high-sensitivity C-reactive protein level, use of angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, loop-diuretics, aspirin, insulin, metformin and sodium-glucose co-transporter 2 inhibitors. Moreover, baseline serum TSP2 levels were independently associated with increase in average E/e' and left atrial volume index (p = 0.04 and < 0.01, respectively). CONCLUSION: Serum TSP2 levels were independently associated with both incident HHF and deterioration in diastolic function in type 2 diabetes. TRIAL REGISTRATION: Not Applicable.


Assuntos
Diabetes Mellitus Tipo 2 , Insuficiência Cardíaca , Inibidores do Transportador 2 de Sódio-Glicose , Humanos , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Remodelação Ventricular , Fatores de Risco , Medição de Risco , Inibidores do Transportador 2 de Sódio-Glicose/efeitos adversos , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/induzido quimicamente , Hospitalização , Trombospondinas , Função Ventricular Esquerda
3.
Inorg Chem ; 61(48): 19058-19066, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36414026

RESUMO

We report the successful growth of high-quality single crystals of Sr0.94Mn0.86Te1.14O6 (SMTO) using a self-flux method. The structural, electronic, and magnetic properties of SMTO are investigated by neutron powder diffraction (NPD), single-crystal X-ray diffraction (SCXRD), thermodynamic, and nuclear magnetic resonance techniques in conjunction with density functional theory calculations. NPD unambiguously determined octahedral (trigonal antiprismatic) coordination for all cations with the chiral space group P312 (no. 149), which is further confirmed by SCXRD data. The Mn and Te elements occupy distinct Wyckoff sites, and minor anti-site defects were observed in both sites. X-ray photoelectron spectroscopy reveals the existence of mixed valence states of Mn in SMTO. The magnetic susceptibility and specific heat data evidence a weak antiferromagnetic order at TN = 6.6 K. The estimated Curie-Weiss temperature θCW = -21 K indicates antiferromagnetic interaction between Mn ions. Furthermore, both the magnetic entropy and the 125Te nuclear spin-lattice relaxation rate showcase that short-range spin correlations persist well above the Néel temperature. Our work demonstrates that Sr0.94(2)Mn0.86(3)Te1.14(3)O6 single crystals realize a noncentrosymmetric triangular antiferromagnet.

4.
Nature ; 535(7610): 122-6, 2016 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-27383945

RESUMO

Chemical reactions at ultracold temperatures are expected to be dominated by quantum mechanical effects. Although progress towards ultracold chemistry has been made through atomic photoassociation, Feshbach resonances and bimolecular collisions, these approaches have been limited by imperfect quantum state selectivity. In particular, attaining complete control of the ground or excited continuum quantum states has remained a challenge. Here we achieve this control using photodissociation, an approach that encodes a wealth of information in the angular distribution of outgoing fragments. By photodissociating ultracold (88)Sr2 molecules with full control of the low-energy continuum, we access the quantum regime of ultracold chemistry, observing resonant and nonresonant barrier tunnelling, matter-wave interference of reaction products and forbidden reaction pathways. Our results illustrate the failure of the traditional quasiclassical model of photodissociation and instead are accurately described by a quantum mechanical model. The experimental ability to produce well-defined quantum continuum states at low energies will enable high-precision studies of long-range molecular potentials for which accurate quantum chemistry models are unavailable, and may serve as a source of entangled states and coherent matter waves for a wide range of experiments in quantum optics.

5.
J Endocrinol Invest ; 45(11): 2149-2156, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35831586

RESUMO

PURPOSE: Thyroid dysfunction in COVID-19 carries clinical and prognostic implications. In this study, we developed a prediction score (ThyroCOVID) for abnormal thyroid function (TFT) on admission amongst COVID-19 patients. METHODS: Consecutive COVID-19 patients admitted to Queen Mary Hospital were prospectively recruited during July 2020-May 2021. Thyroid-stimulating hormone (TSH), free thyroxine (fT4) and free triiodothyronine (fT3) were measured on admission. Multivariable logistic regression analysis was performed to identify independent determinants of abnormal TFTs. ThyroCOVID was developed based on a clinical model with the lowest Akaike information criteria. RESULTS: Five hundred and forty six COVID-19 patients were recruited (median age 50 years, 45.4% men, 72.9% mild disease on admission). 84 patients (15.4%) had abnormal TFTs on admission. Patients with abnormal TFTs were more likely to be older, have more comorbidities, symptomatic, have worse COVID-19 severity, higher SARS-CoV-2 viral loads and more adverse profile of acute-phase reactants, haematological and biochemical parameters. ThyroCOVID consisted of five parameters: symptoms (malaise), comorbidities (ischaemic heart disease/congestive heart failure) and laboratory parameters (lymphocyte count, C-reactive protein, and SARS-CoV-2 cycle threshold values). It was able to identify abnormal TFT on admission with an AUROC of 0.73 (95% CI 0.67-0.79). The optimal cut-off of 0.15 had a sensitivity of 75.0%, specificity of 65.2%, negative predictive value of 93.5% and positive predictive value of 28.1% in identifying abnormal TFTs on admission amongst COVID-19 patients. CONCLUSION: ThyroCOVID, a prediction score to identify COVID-19 patients at risk of having abnormal TFT on admission, was developed based on a cohort of predominantly non-severe COVID-19 patients.


Assuntos
COVID-19 , Tri-Iodotironina , Proteína C-Reativa , COVID-19/diagnóstico , COVID-19/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Testes de Função Tireóidea , Glândula Tireoide , Tireotropina , Tiroxina
6.
Anaesthesia ; 77(5): 562-569, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35262180

RESUMO

Comprehensive evidence regarding the treatment of non-anaemic iron deficiency in patients undergoing valvular heart surgery is lacking. This study aimed to investigate the association between non-anaemic iron deficiency and postoperative outcomes in these patients. We retrospectively analysed 321 patients of which 180 (56%) had iron deficiency (defined as serum ferritin < 100 ng.ml-1 or < 300 ng.ml-1 with transferrin saturation < 20%). While the iron-deficient group had lower pre-operative haemoglobin levels than the non-iron deficient group (median (IQR [range]) 134 (127-141 [120-172]) g.l-1 , 143 (133-150 [120-179]) g.l-1 , p = 0.001), there was no between-group difference in allogeneic red blood cell transfusion. Median (IQR [range]) days alive and out of hospital at postoperative day 90 was 1 day shorter in the iron-deficient group (80 (77-82 [9-85]) days vs. 81 (79-83 [0-85]) days, p = 0.026). In multivariable analysis, only cardiopulmonary bypass duration (p = 0.032) and intra-operative allogeneic red blood cell transfusion (p = 0.011) were significantly associated with reduced days alive and out of hospital at postoperative day 90. Iron deficiency did not exert any adverse influence on secondary outcomes except length of hospital stay. Our findings indicate that non-anaemic iron deficiency alone is not associated with adverse effects in patients undergoing valvular heart surgery when it does not translate into an increased risk of allogeneic transfusion.


Assuntos
Anemia , Procedimentos Cirúrgicos Cardíacos , Deficiências de Ferro , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Hospitais , Humanos , Cuidados Pré-Operatórios , Estudos Retrospectivos
7.
J Eur Acad Dermatol Venereol ; 36(12): 2414-2422, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35841308

RESUMO

BACKGROUND: Nickel, the fifth most common element on Earth, is the leading inducer of contact allergies in humans, with potent immunological effects. Nickel-induced contact allergies predominantly affect females. Maternal exposure to nickel has been associated with several developmental abnormalities. However, how a maternal nickel exposure affects the development of atopic diathesis and immune abnormalities in children has never been addressed. OBJECTIVES: We aimed to determine whether maternal nickel exposure affects the development of atopic dermatitis and immune abnormalities in their children. METHODS: Using a birth cohort study, we analysed 140 mother-child pairs recruited in 2012-2015 from central Taiwan. Maternal exposure to nickel was estimated using urinary nickel levels measured by inductively coupled plasma mass spectrometry (ICP-MS). The serum levels of 65 analytes and IgE in 3-year-old children were profiled with a multiplex ELISA. The correlation between the maternal urinary nickel concentration and serum analyte levels was assessed using Spearmen's correlation. Multivariant regression analysis was performed to evaluate the association between maternal urinary nickel levels and serum analyte concentrations in their children. RESULTS: The geometric means of the maternal urinary nickel and the children's serum IgE levels were 2.27 µg/L and 69.71 IU/mL, respectively. The maternal nickel exposure was associated with increased serum levels of IL-1ß, IL-2, TNF-α, and leukaemia inhibitory factor (LIF) but with decreased serum levels of matrix metalloproteinase-1 (MMP-1), IL-2R, and eotaxin-1 in the children. In addition, the development of childhood atopic dermatitis at 3 years old was significantly associated with the child's serum levels of IgE and IL-2R, but it was negatively associated with the maternal nickel exposure. CONCLUSIONS: This is the first study showing the potential immunological effects of maternal nickel exposure in their children at an early developmental stage.


Assuntos
Dermatite Atópica , Efeitos Tardios da Exposição Pré-Natal , Gravidez , Feminino , Humanos , Pré-Escolar , Estudos de Coortes , Níquel/efeitos adversos , Coorte de Nascimento , Imunoglobulina E , Citocinas
8.
Hong Kong Med J ; 28(1): 7-15, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35249888

RESUMO

INTRODUCTION: Because of the ageing population in Hong Kong, there is an increasing incidence of total knee arthroplasties (TKA) conducted in patients aged >80 years. METHODS: This retrospective case-control study enrolled all patients who were aged >80 years and underwent fast-track primary TKA between 2011 and 2015. Their outcomes were compared with the outcomes of a matched control group of younger patients who underwent fast-track TKA in the same period. RESULTS: In total, 220 patients were included in this study with a follow-up period of at least 2 years (mean=3.2 years; range, 2-5 years); 112 (51%) were octogenarians and 108 (49%) were non-octogenarians. Greater improvement in Knee Society Score was found in the octogenarian group at 1 year after surgery (46 ± 19 vs 39 ± 16, P=0.018). The incidence of complications was higher in the octogenarian group (15.2% vs 4.6%, P=0.009). There were no significant differences in the incidence of major complications, the rate of intensive care unit admission, or the 1-year mortality rate between the two groups. After adjustment for confounding factors, Charlson Comorbidity Index >5, history of major cerebrovascular accident, and history of peptic ulcer disease were predictive of complications after fast-track TKA (P=0.039, P=0.016, and P=0.007, respectively); octogenarian status was not predictive of complications. CONCLUSIONS: Octogenarians had greater improvement in Knee Society Score at 1 year after fast-track TKA, compared with non-octogenarians, but there were no significant differences in the incidences of mortality or major complications.


Assuntos
Artroplastia do Joelho , Idoso de 80 Anos ou mais , Artroplastia do Joelho/efeitos adversos , Estudos de Casos e Controles , Humanos , Incidência , Articulação do Joelho/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
9.
Br J Anaesth ; 126(1): 181-190, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32690247

RESUMO

BACKGROUND: Accurate assessment of functional capacity, a predictor of postoperative morbidity and mortality, is essential to improving surgical planning and outcomes. We assessed if all 12 items of the Duke Activity Status Index (DASI) were equally important in reflecting exercise capacity. METHODS: In this secondary cross-sectional analysis of the international, multicentre Measurement of Exercise Tolerance before Surgery (METS) study, we assessed cardiopulmonary exercise testing and DASI data from 1455 participants. Multivariable regression analyses were used to revise the DASI model in predicting an anaerobic threshold (AT) >11 ml kg-1 min-1 and peak oxygen consumption (VO2 peak) >16 ml kg-1 min-1, cut-points that represent a reduced risk of postoperative complications. RESULTS: Five questions were identified to have dominance in predicting AT>11 ml kg-1 min-1 and VO2 peak>16 ml.kg-1min-1. These items were included in the M-DASI-5Q and retained utility in predicting AT>11 ml.kg-1.min-1 (area under the receiver-operating-characteristic [AUROC]-AT: M-DASI-5Q=0.67 vs original 12-question DASI=0.66) and VO2 peak (AUROC-VO2 peak: M-DASI-5Q 0.73 vs original 12-question DASI 0.71). Conversely, in a sensitivity analysis we removed one potentially sensitive question related to the ability to have sexual relations, and the ability of the remaining four questions (M-DASI-4Q) to predict an adequate functional threshold remained no worse than the original 12-question DASI model. Adding a dynamic component to the M-DASI-4Q by assessing the chronotropic response to exercise improved its ability to discriminate between those with VO2 peak>16 ml.kg-1.min-1 and VO2 peak<16 ml.kg-1.min-1. CONCLUSIONS: The M-DASI provides a simple screening tool for further preoperative evaluation, including with cardiopulmonary exercise testing, to guide perioperative management.


Assuntos
Teste de Esforço/métodos , Teste de Esforço/estatística & dados numéricos , Tolerância ao Exercício , Nível de Saúde , Complicações Pós-Operatórias/prevenção & controle , Cuidados Pré-Operatórios/métodos , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco , Inquéritos e Questionários/estatística & dados numéricos
10.
Eur J Pediatr ; 180(1): 99-107, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32556509

RESUMO

Pain management is an important issue which impacts the prognosis of neonates in neonatal intensive care units. Evidence has shown that professionals' knowledge and attitudes regarding pain management can impact the quality of their practice. The purpose of this study was to evaluate the knowledge, attitudes, and practices of neonatal professionals regarding neonatal pain management. A cross-sectional study was performed involving neonatal physicians and nurses, using a research questionnaire to investigate the knowledge and attitudes of professionals as well as to assess their practice of pain management. Research found an apparent discrepancy between the knowledge levels of neonatologists and nurses regarding pain assessment and management, with nurses displaying weaker professional knowledge and more negative attitudes toward pain management than did neonatologists. Additionally, research revealed a lack of knowledge and negative attitudes among participants regarding the provision of sufficient opioid analgesics to sick infants during invasive procedures and even for dying neonates. There is an urgent need for continuing education regarding neonatal pain management with the goal of empowering neonatal professionals; further research is needed into the question of how to translate education into more reliable practice.Conclusion: This research provides useful information regarding the knowledge, attitudes, and clinical practice of neonatal pain management among neonatologists and nurses and points out some differences in the knowledge levels of these two groups. What is Known: •Neonates can perceive and respond to pain stimuli by showing their biological signals similarly to children and adults. •Untreated or insufficient pain management for high-risk neonates has short-term. negative effects and may also induce long-term negative effects. What is New: •The level of knowledge, the attitudes, and the practices regarding neonatal pain in intensive care are different among neonatal professionals. •There is an urgent need to provide interdisciplinary continuing education to improve the knowledge of neonatal professionals and encourage them to more highly prioritize neonatal pain management.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Manejo da Dor , Adulto , Atitude do Pessoal de Saúde , Criança , Estudos Transversais , Humanos , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Neonatologistas , Inquéritos e Questionários
11.
J Endocrinol Invest ; 44(3): 523-530, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32602078

RESUMO

PURPOSE: Findings on trabecular bone score (TBS), an index of bone quality, have been reported in prediabetes defined by impaired fasting glucose or HbA1c. Here, we assessed the bone mineral density (BMD) and TBS in prediabetes individuals with impaired glucose tolerance (IGT), and investigated the association of these bone parameters with serum levels of fibroblast growth factor 21 (FGF21), a hormone implicated in bone metabolism and with higher levels in IGT. METHODS: Chinese postmenopausal women aged 55-80 years, without diabetes, were recruited from the Hong Kong Cardiovascular Risk Factor Prevalence Study in 2016-2018. Normal glucose tolerance (NGT) was defined by fasting glucose < 5.6 mmol/L and 2-h plasma glucose (2hG) < 7.8 mmol/L, and IGT by 2hG 7.8-11 mmol/L. Serum levels of FGF21 and other bone metabolism regulators were measured. Insulin sensitivity was assessed by the Matsuda index. Independent determinants of TBS were evaluated using multivariable stepwise linear regression. RESULTS: 173 individuals with NGT and 73 with IGT were included. TBS was lower in those with IGT compared to those with NGT, while BMD was comparable. Individuals with IGT had significantly higher serum FGF21 levels, which in turn showed an independent inverse relationship with TBS, attenuated after inclusion of the Matsuda index. Serum FGF21 levels, however, did not correlate with BMD. CONCLUSION: Among Chinese postmenopausal women, bone quality was worse in IGT, despite comparable bone density. FGF21 levels showed a significant independent inverse relationship with TBS, partly attributed to insulin resistance. Whether FGF21 contributes to the impaired bone quality in IGT remains speculative.


Assuntos
Biomarcadores/metabolismo , Glicemia/análise , Densidade Óssea , Fatores de Crescimento de Fibroblastos/metabolismo , Fraturas Ósseas/patologia , Intolerância à Glucose/complicações , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Estudos Transversais , Feminino , Seguimentos , Fraturas Ósseas/etiologia , Fraturas Ósseas/metabolismo , Teste de Tolerância a Glucose , Humanos , Resistência à Insulina , Pessoa de Meia-Idade , Prognóstico
12.
Rhinology ; 59(3): 328-336, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34091656

RESUMO

BACKGROUND: Exosomes are critical mediators of intercellular communication and could be involved in many human diseases; however, little is known about the role of exosomes in nasal polyps (NP). METHODS: Exosomes in nasal lavage fluids (NLF) were isolated by ultracentrifugation. Exosome identity was validated by nanoparticle tracking analysis (NTA), transmission electron microscopy (TEM) and specific exosomal markers. The exosome proteome was revealed by LC-MS/MS, and the expression of the candidate exosomal protein, mucin 5AC, was confirmed by Western blot analysis and immunohistochemistry (IHC). Cellular uptake of the exosomes was monitored by fluorescence confocal microscopy and the ensuing effects on COX-2, VEGF and MMP-2/MMP-9 were determined by Western blotting, ELISA and gelatin zymography, respectively. RESULTS: Mass spectrometry analysis and subsequent verification by Western blotting identified that mucin 5AC was significantly upregulated in exosomes from NLFs of NP patients. Moreover, the expression of mucin 5AC was increased in the tissue specimens of the NP patients. Functional assays suggest that the mucin 5 AC-enriched exosomes could be effectively taken up by chronic rhinosinusitis without NP (CRSsNP)-derived fibroblasts, the control cells, resulting in a significant increase in the expression of COX-2, VEGF and MMP-9. CONCLUSIONS: Mucin 5AC, the major airway mucin, cannot only be carried and transferred by nasal exosomes, but may also promote tissue remodeling and angiogenesis and thus could be a potential therapeutic target of NP.


Assuntos
Exossomos , Pólipos Nasais , Cromatografia Líquida , Ciclo-Oxigenase 2 , Humanos , Metaloproteinase 9 da Matriz , Mucina-5AC , Líquido da Lavagem Nasal , Espectrometria de Massas em Tandem , Fator A de Crescimento do Endotélio Vascular
13.
Osteoporos Int ; 31(10): 1955-1964, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32385660

RESUMO

Type 2 diabetes is associated with an increased risk of hip fractures. We hypothesize that long-term glycemic variability predicts incident hip fractures. We demonstrated that HbA1c variability predicted incident hip fractures independent of mean HbA1c, suggesting the potential benefits of minimizing glycemic variability in addition to optimizing mean glycemia for bone health. INTRODUCTION: Type 2 diabetes is associated with an increased risk of hip fractures, and a linear relationship between HbA1c levels and hip fracture incidence has been observed. We hypothesize that HbA1c variability also predicts incident hip fractures in type 2 diabetes. METHODS: Chinese individuals with type 2 diabetes aged ≥ 60 years were identified from electronic health records in Hong Kong between 2008 and 2012 and observed for incident hip fractures. Hip fracture was defined by the International Classification of Diseases (Ninth Revision) code 820. HbA1c variability was determined using standard deviation, adjusted standard deviation, and coefficient of variation of HbA1c measurements in the 5 years preceding the entry date. Multivariable Cox regression analysis was used to evaluate associations between HbA1c variability and incident hip fractures. RESULTS: A total of 83,282 participants were included. Their mean age was 71.3 ± 7.5 years, duration of diabetes 11.7 ± 7.7 years, baseline HbA1c 56.6 ± 13.5 mmol/mol (7.33 ± 1.23%), and median follow-up 6.8 years. All indices of HbA1c variability were significant independent predictors of incident hip fractures, with an adjusted hazard ratio of up to 1.29 (all p < 0.001), and remained to be independent predictors across groups of different intensity of glycemic control. Mean HbA1c ≥ 64 mmol/mol (8.0%) was associated with a 25% increase in incident hip fractures compared with mean HbA1c < 53 mmol/mol (7.0%). CONCLUSION: HbA1c variability is an independent positive predictor of hip fracture in type 2 diabetes, across the spectrum of varying degree of glycemic control, while a high HbA1c is also not advisable from the perspective of bone health.


Assuntos
Diabetes Mellitus Tipo 2 , Fraturas do Quadril , Idoso , Glicemia , China/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Hemoglobinas Glicadas/análise , Fraturas do Quadril/epidemiologia , Fraturas do Quadril/etiologia , Humanos , Pessoa de Meia-Idade , Fatores de Risco
14.
Phys Rev Lett ; 125(15): 153001, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33095629

RESUMO

Optical trapping of molecules with long coherence times is crucial for many protocols in quantum information and metrology. However, the factors that limit the lifetimes of the trapped molecules remain elusive and require improved understanding of the underlying molecular structure. Here we show that measurements of vibronic line strengths in weakly and deeply bound ^{88}Sr_{2} molecules, combined with ab initio calculations, allow for unambiguous identification of vibrational quantum numbers. This, in turn, enables the construction of refined excited potential energy curves, informing the selection of magic wavelengths that facilitate long vibrational coherence. We demonstrate Rabi oscillations between far-separated vibrational states that persist for nearly 100 ms.

15.
Phys Rev Lett ; 124(4): 047204, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32058744

RESUMO

dc and ac magnetic susceptibility, magnetization, specific heat, and Raman scattering measurements are combined to probe low-lying spin excitations in α-Ru_{1-x}Ir_{x}Cl_{3} (x≈0.2), which realizes a disordered spin liquid. At intermediate energies (ℏω>3 meV), Raman spectroscopy evidences linearly ω-dependent Majorana-like excitations, obeying Fermi statistics. This points to robustness of a Kitaev paramagnetic state under spin vacancies. At low energies below 3 meV, we observe power-law dependences and quantum-critical-like scalings of the thermodynamic quantities, implying the presence of a weakly divergent low-energy density of states. This scaling phenomenology is interpreted in terms of the random hoppings of Majorana fermions. Our results demonstrate an emergent hierarchy of spin excitations in a diluted Kitaev honeycomb system subject to spin vacancies and bond randomness.

16.
Br J Dermatol ; 182(5): 1205-1213, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31408190

RESUMO

BACKGROUND: Acral melanoma (AM) is the most common histopathological subtype of malignant melanoma in Asians. However, differences in the mutational profiles underlying AM and nonacral cutaneous melanoma (NAM) in Asians are not well understood. OBJECTIVES: To augment the understanding of the prevalence, patterns and associations of various mutations between different subtypes of melanoma. METHODS: We performed comprehensive genomic profiling of 409 cancer-associated genes, using next-generation sequencing, in 66 primary melanomas comprised of 45 AMs and 21 NAMs. RESULTS: Most of the AMs (n = 27/45; 60%), but only five of 21 (24%) NAMs, were triple wild-type (triple-WT) tumours. Compared with AMs, NAMs exhibited a significantly higher frequency of BRAF mutations. The frequencies of NRAS/KRAS mutations, cell-cycle aberrations, copy number gains in BIRC2, BIRC3 and BIRC5, and gains of receptor tyrosine kinase genes were significantly higher in AMs. Ulceration was found at significantly higher rates in the AMs and NAMs with cell-cycle aberrations and gains of receptor tyrosine kinase genes. Notably, cell-cycle aberrations and copy number gains in BIRC2, BIRC3 and BIRC5 were significantly associated with poor melanoma-specific survival in the 66 patients with melanoma and especially in the 45 patients with AM. Multivariate analysis showed that lymph node metastasis and cell-cycle aberrations were independent prognostic factors of melanoma-specific survival. CONCLUSIONS: This study strengthens our understanding of the patterns and clinical associations of oncogenic mutations in AMs and NAMs in Asians. What's already known about this topic? Mutation frequencies of driver genes vary between melanoma subtypes. Acral melanoma is the most common subtype of melanoma in Asians. KIT mutations and copy number variations occur more frequently in the acral subtype of melanoma than in the nonacral subtype What does this study add? NRAS/KRAS mutations, cell-cycle aberrations, copy number gains in BIRC2, BIRC3 and BIRC5, and amplifications of receptor tyrosine kinase genes were significantly enriched in acral melanoma and could be potential targets for treatment. Melanomas with cell-cycle aberrations and gains in receptor tyrosine kinase genes were significantly more likely to contain ulceration. What is the translational message? Cell-cycle aberrations and copy number gains in BIRC2, BIRC3 and BIRC5 were significantly associated with poor melanoma-specific survival. These observations should be explored further for future drug development.


Assuntos
Melanoma , Neoplasias Cutâneas , Variações do Número de Cópias de DNA , Humanos , Melanoma/genética , Mutação/genética , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/genética , Taiwan/epidemiologia
17.
J Appl Microbiol ; 128(3): 907-918, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31710752

RESUMO

AIMS: Quorum quenching (QQ) is an attractive strategy for mitigating biofouling in membrane bioreactors (MBRs). However, the effects of QQ on the activated sludge (AS) process have not been adequately evaluated. This study investigated the long-term effects of QQ on a laboratory-scale anoxic-oxic MBR, focusing on AS performance and microbial community. METHODS AND RESULTS: Anoxic-oxic MBRs with and without QQ were operated for 91 days. QQ did not affect COD and TN removal efficiencies over the experimental period, during which its activity remained >90%. QQ reduced floc size by approximately 8% but had no effect on biomass concentration. AS microbial communities were regularly analysed using massively parallel sequencing. AS bacterial communities were temporally dynamic irrespective of QQ presence, for example, a temporal increase in bacterial diversity and a temporal decay of community similarity. QQ counteracted the temporal change in diversity and the temporal distance-community decay. Community comparison revealed that QQ changed the successional trajectory of the AS community at a late period, because it decelerated temporal changes of specific members, such as Thiothrix and Sphingomonadaceae*. Correlation networks revealed that QQ increased network clustering, complexity and density. The combined results suggest that the tighter microbial association by QQ increased the community resistance. CONCLUSIONS: QQ can enhance the diversity and stability of the AS community in MBR by counteracting the innate temporal change in community structure. SIGNIFICANCE AND IMPACT OF THE STUDY: Our findings are useful for the further advancement of QQ-based strategies in engineered microbial environments.


Assuntos
Reatores Biológicos/microbiologia , Microbiota , Percepção de Quorum , Esgotos/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Incrustação Biológica/prevenção & controle , Floculação , Membranas Artificiais , Microbiota/genética , Fatores de Tempo , Eliminação de Resíduos Líquidos
18.
Clin Radiol ; 75(11): 879.e1-879.e6, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32727657

RESUMO

AIM: To evaluate the technical feasibility and safety of percutaneous recanalisation of benign postoperative hepaticojejunostomy strictures using the reverse end of a microwire. MATERIALS AND METHODS: Twenty-one patients with benign postoperative hepaticojejunostomy strictures that had failed to recanalise following management with conventional percutaneous techniques from January 2012 to March 2019 were included in the study. The stricture was punctured by the reverse end of a microwire. Subsequently, serial balloon dilatation and covered stent placement was performed. Technical as well as clinical success, complications, and patency of the hepaticojejunostomy were evaluated. RESULTS: Technical success was achieved in 19 of 21 (90.5%) patients. The mean number of treatment sessions was 1.2 (range, 1-2). The obstructive symptoms were resolved within 3 days after the procedure in 19 patients (100%). There were no major complications. The 1-year and 3-year patency rates were 76.9% and 61.5%, respectively. CONCLUSION: Percutaneous recanalisation using the reverse end of a microwire is technically feasible and safe in the treatment of benign postoperative hepaticojejunostomy strictures. This technique is useful when the conventional percutaneous technique cannot be used to cross the stricture.


Assuntos
Constrição Patológica/etiologia , Doenças do Jejuno/etiologia , Jejuno/diagnóstico por imagem , Jejuno/cirurgia , Hepatopatias/etiologia , Fígado/cirurgia , Pâncreas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Procedimentos Cirúrgicos do Sistema Biliar/efeitos adversos , Constrição Patológica/diagnóstico por imagem , Constrição Patológica/cirurgia , Feminino , Humanos , Doenças do Jejuno/diagnóstico por imagem , Doenças do Jejuno/cirurgia , Fígado/diagnóstico por imagem , Hepatopatias/diagnóstico por imagem , Hepatopatias/cirurgia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
19.
Phys Rev Lett ; 122(16): 167202, 2019 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-31075021

RESUMO

We report on magnetization M(H), dc and ac magnetic susceptibility χ(T), specific heat C_{m}(T) and muon spin relaxation (µSR) measurements of the Kitaev honeycomb iridate Cu_{2}IrO_{3} with quenched disorder. In spite of the chemical disorders, we find no indication of spin glass down to 260 mK from the C_{m}(T) and µSR data. Furthermore, a persistent spin dynamics observed by the zero-field muon spin relaxation evidences an absence of static magnetism. The remarkable observation is a scaling relation of χ[H,T] and M[H,T] in H/T with the scaling exponent α=0.26-0.28, expected from bond randomness. However, C_{m}[H,T]/T disobeys the predicted universal scaling law, pointing towards the presence of additional low-lying excitations on the background of bond-disordered spin liquid. Our results signify a many-faceted impact of quenched disorder in a Kitaev spin system due to its peculiar bond character.

20.
Eur J Neurol ; 26(2): 261-267, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30168901

RESUMO

BACKGROUND AND PURPOSE: The P2Y12 receptor, a well-known factor in the platelet activation pathway, plays a role in thrombosis as well as systemic inflammation. Clopidogrel, a prototype P2Y12 receptor antagonist, reportedly decreases inflammation and systemic infection. The aim of this study was to evaluate whether clopidogrel use decreases the risk of post-stroke infection following ischaemic stroke. METHODS: A total of 1643 patients with acute ischaemic stroke (within 7 days after onset) were included for analysis between March 2010 and December 2015. Patients were categorized into two groups (clopidogrel users versus clopidogrel non-users), and clinical characteristics and risks of post-stroke infection were compared between the two groups. The inverse probability of treatment weighting using propensity scores for baseline imbalance adjustments was applied. RESULTS: Of the included patients (mean age 67.7 years; men 60.6%), 670 (40.8%) patients were clopidogrel users and 164 (10.0%) patients had post-stroke infection. The proportion of patients with post-stroke infection was significantly lower in clopidogrel users compared to clopidogrel non-users (6.7% vs. 12.2%, P ≤ 0.001). Moreover, clopidogrel users were less likely to be admitted to the intensive care unit (13.3% vs. 35.3%, P = 0.006). A multivariate analysis with inverse probability of treatment weighting revealed that clopidogrel users exhibited a lower risk of post-stroke infection (odds ratio 0.56, 95% confidence interval 0.42-0.75) and intensive care unit admission (odds ratio 0.34, 95% confidence interval 0.22-0.53). CONCLUSIONS: The study suggested that clopidogrel users exhibit a lower risk of infection and develop less severe infections after ischaemic stroke. Further prospective studies are needed.


Assuntos
Isquemia Encefálica/complicações , Clopidogrel/uso terapêutico , Controle de Infecções/métodos , Infecções/tratamento farmacológico , Acidente Vascular Cerebral/complicações , Idoso , Isquemia Encefálica/tratamento farmacológico , Feminino , Humanos , Infecções/etiologia , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/uso terapêutico , Estudos Prospectivos , Acidente Vascular Cerebral/tratamento farmacológico
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