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1.
Nano Lett ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38620181

RESUMO

Advancements in photonic quantum information systems (QIS) have driven the development of high-brightness, on-demand, and indistinguishable semiconductor epitaxial quantum dots (QDs) as single photon sources. Strain-free, monodisperse, and spatially sparse local-droplet-etched (LDE) QDs have recently been demonstrated as a superior alternative to traditional Stranski-Krastanov QDs. However, integration of LDE QDs into nanophotonic architectures with the ability to scale to many interacting QDs is yet to be demonstrated. We present a potential solution by embedding isolated LDE GaAs QDs within an Al0.4Ga0.6As Huygens' metasurface with spectrally overlapping fundamental electric and magnetic dipolar resonances. We demonstrate for the first time a position- and size-independent, 1 order of magnitude increase in the collection efficiency and emission lifetime control for single-photon emission from LDE QDs embedded within the Huygens' metasurfaces. Our results represent a significant step toward leveraging the advantages of LDE QDs within nanophotonic architectures to meet the scalability demands of photonic QIS.

2.
Malays J Pathol ; 46(1): 79-89, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38682847

RESUMO

INTRODUCTION: Beta-lactamase producing bacterial infection has been on surge due to selection pressure and injudicious antibiotics usage. Organisms that co-produced more than one beta lactamase enzyme posed diagnostic challenges which may result in inadequate treatment. To date, there is no standardised guideline offering phenotypic detection of AmpC ß-lactamase. The purpose of this study was to determine the prevalence of ESBLs, AmpC ß-lactamase and co-producer organisms in a teaching hospital. MATERIALS AND METHODS: Three hundred and four isolates of E. coli and Klebsiella sp. had been selected via convenient sampling. These isolates were identified using conventional laboratory methods and their antimicrobial susceptibilities were determined using disc diffusion method. Those isolates were then proceeded with ESBL confirmatory test, cloxacillin-containing Muller Hinton confirmatory test, modified double disk synergy test and AmpC disk test. RESULTS: Out of 304 isolates, 159 isolates were E. coli and 145 were Klebsiella sp. The prevalence of organisms which co-produced AmpC ß-lactamase and ESBL enzymes were 3.0%. Besides that, 39 cefoxitin resistant and three cefoxitin susceptible isolates (13.8%) were proven to produce AmpC ß-lactamase through AmpC disk test. Through the CLSI confirmatory test, 252 (82.9%) isolates were identified as ESBLs producers and the prevalence increased slightly when cloxacillin-containing Muller Hinton were used. Only three ESBLs positive organisms were positive for modified double disk synergy test. CONCLUSION: Distinguishing between AmpC ß-lactamase and ESBL-producing organisms has epidemiological significance as well as therapeutic importance. Moreover, AmpC ß-lactamase and ESBLs co-producing organisms can lead to false negative ESBL confirmatory test. Therefore, knowing the local prevalence can guide the clinician in navigating the treatment.


Assuntos
Escherichia coli , Klebsiella , beta-Lactamases , Humanos , Antibacterianos/farmacologia , Proteínas de Bactérias/análise , beta-Lactamases/biossíntese , beta-Lactamases/metabolismo , Escherichia coli/isolamento & purificação , Escherichia coli/enzimologia , Escherichia coli/efeitos dos fármacos , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/epidemiologia , Hospitais de Ensino , Klebsiella/enzimologia , Klebsiella/efeitos dos fármacos , Klebsiella/isolamento & purificação , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/microbiologia , Testes de Sensibilidade Microbiana , Prevalência , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia
3.
J Cancer Res Clin Oncol ; 149(14): 12903-12912, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37466791

RESUMO

PURPOSE: Patients with BRAFV600E-mutant metastatic colorectal cancer (mCRC) have a dismal prognosis. The best strategies in these patients remain elusive. Against this background, we report the clinical course of patients with BRAFV600E-mutant mCRC to retrieve the best treatment strategy. PATIENTS AND METHODS: Clinico-pathological data were extracted from the electronic health records. Kaplan-Meier method was used to estimate overall (OS) and progression-free survival (PFS). Objective response rate (ORR) was assessed according to RECIST 1.1. RESULTS: In total, 51 patients were enrolled. FOLFOXIRI was administered to 12 patients; 29 patients received FOLFOX or FOLFIRI as first-line treatment. Median OS was 17.6 months. Median PFS with FOLFOXIRI (13.0 months) was significantly prolonged (HR 0.325) as compared to FOLFOX/FOLFIRI (4.3 months). However, this failed to translate into an OS benefit (p = 0.433). Interestingly, addition of a monoclonal antibody to chemotherapy associated with superior OS (HR 0.523). A total of 64.7% patients received further-line therapy, which included a BRAF inhibitor in 17 patients. Targeted therapy associated with very favourable OS (25.1 months). CONCLUSION: Patients with BRAFV600E-mutated mCRC benefit from the addition of an antibody to first-line chemotherapy. Further-line treatment including a BRAF inhibitor has a dramatic impact on survival.

4.
Med J Malaysia ; 78(3): 379-388, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37271849

RESUMO

INTRODUCTION: The magnitude of Coronavirus Disease 2019 (COVID-19) infection among the elderly population is expected to rise. Our study compares the clinical and computed tomographical (CT) features of pulmonary thromboembolic (PTE) disease associated with COVID-19 infection in geriatric and non-geriatric cases, and explores the 60-day mortality rate in these two groups. MATERIALS AND METHODS: We conducted this retrospective cross-sectional study in Hospital Tengku Ampuan Rahimah, Selangor, Malaysia. Patients admitted in April 2021 and May 2021 with concomitant COVID-19 infection and PTE disease were included. Demographic, clinical and laboratory data were retrieved, whilst CTPA images were analysed by a senior radiologist. RESULTS: A total of 150 patients were recruited, comprising 45 geriatric patients and 105 non-geriatric patients. The prevalence rate of hypertension, diabetes mellitus and dyslipidaemia were higher among the geriatric cohort. Evidently, the percentage of patients with fever and diarrhoea were significantly higher among the non-geriatric cohort. The geriatric cohort also recorded a significantly lower absolute lymphocyte count at presentation and albumin level during admission. Despite earlier presentation, the geriatric cohort suffered from more severe diseases. Analysis of the CT features demonstrated that the most proximal pulmonary thrombosis specifically limited to the segmental and subsegmental pulmonary arteries in both cohorts. The elderly suffered from a significantly higher inhospital mortality rate and their cumulative probability of survival was significantly lower. CONCLUSION: Typical COVID-19 symptoms may be absent among the elderly, prompting a lower threshold of suspicion during the COVID-19 pandemic. Additionally, the elderly demonstrated a higher probability of adverse outcomes despite earlier presentation and treatment.


Assuntos
COVID-19 , Embolia Pulmonar , Humanos , Idoso , COVID-19/complicações , COVID-19/epidemiologia , SARS-CoV-2 , Pandemias , Estudos Retrospectivos , Estudos Transversais , Embolia Pulmonar/epidemiologia , Embolia Pulmonar/etiologia
5.
ESMO Open ; 8(3): 101539, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37148593

RESUMO

BACKGROUND: Pancreatic cancer has a dismal prognosis. One reason is resistance to cytotoxic drugs. Molecularly matched therapies might overcome this resistance but the best approach to identify those patients who may benefit is unknown. Therefore, we sought to evaluate a molecularly guided treatment approach. MATERIALS AND METHODS: We retrospectively analyzed the clinical outcome and mutational status of patients with pancreatic cancer who received molecular profiling at the West German Cancer Center Essen from 2016 to 2021. We carried out a 47-gene DNA next-generation sequencing (NGS) panel. Furthermore, we assessed microsatellite instability-high/deficient mismatch repair (MSI-H/dMMR) status and, sequentially and only in case of KRAS wild-type, gene fusions via RNA-based NGS. Patient data and treatment were retrieved from the electronic medical records. RESULTS: Of 190 included patients, 171 had pancreatic ductal adenocarcinoma (90%). One hundred and three patients had stage IV pancreatic cancer at diagnosis (54%). MMR analysis in 94 patients (94/190, 49.5%) identified 3 patients with dMMR (3/94, 3.2%). Notably, we identified 32 patients with KRAS wild-type status (16.8%). To identify driver alterations in these patients, we conducted an RNA-based fusion assay on 13 assessable samples and identified 5 potentially actionable fusions (5/13, 38.5%). Overall, we identified 34 patients with potentially actionable alterations (34/190, 17.9%). Of these 34 patients, 10 patients (10/34, 29.4%) finally received at least one molecularly targeted treatment and 4 patients had an exceptional response (>9 months on treatment). CONCLUSIONS: Here, we show that a small-sized gene panel can suffice to identify relevant therapeutic options for pancreatic cancer patients. Informally comparing with previous large-scale studies, this approach yields a similar detection rate of actionable targets. We propose molecular sequencing of pancreatic cancer as standard of care to identify KRAS wild-type and rare molecular subsets for targeted treatment strategies.


Assuntos
Neoplasias Pancreáticas , Proteínas Proto-Oncogênicas p21(ras) , Humanos , Estudos Retrospectivos , Proteínas Proto-Oncogênicas p21(ras)/genética , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Genômica , Neoplasias Pancreáticas
6.
Med J Malaysia ; 78(2): 155-162, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36988524

RESUMO

INTRODUCTION: The co-existence of coronavirus disease 2019 (COVID-19) and pulmonary thromboembolic (PTE) disease poses a great clinical challenge. To date, few researches have addressed this important clinical issue among the South-East Asian populations. The objectives of this study were as follow: (1) to describe the clinical characteristics and computed tomographical (CT) features of patients with PTE disease associated with COVID-19 infection and (2) to compare these parameters with those COVID-19 patients without PTE disease. MATERIALS AND METHODS: This cross-sectional study with retrospective record review was conducted in Hospital Tengku Ampuan Rahimah, Selangor, Malaysia. We included all hospitalised patients with confirmed COVID-19 infection who had undergone CT pulmonary angiogram (CTPA) examinations for suspected PTE disease between April 2021 and May 2021. Clinical data and laboratory data were extracted by trained data collectors, whilst CT images retrieved were analysed by a senior radiologist. Data analysis was performed using Statistical Package for the Social Sciences (SPSS) version 20. RESULTS: We studied 184 COVID-19 patients who were suspected to have PTE disease. CTPA examinations revealed a total of 150 patients (81.5%) suffered from concomitant PTE disease. Among the PTE cohort, the commonest comorbidities were diabetes mellitus (n=78, 52.0%), hypertension (n=66, 44.0%) and dyslipidaemia (n=25, 16.7%). They were generally more ill than the non-PTE cohort as they reported a significantly higher COVID-19 disease category during CTPA examination with p=0.042. Expectedly, their length of both intensive care unit stays (median number of days 8 vs. 3; p=0.021) and hospital stays (median number of days 14.5 vs. 12; p=0.006) were significantly longer. Intriguingly, almost all the subjects had received either therapeutic anticoagulation or thromboprophylactic therapy prior to CTPA examination (n=173, 94.0%). Besides, laboratory data analysis identified a significantly higher peak C-reactive protein (median 124.1 vs. 82.1; p=0.027) and ferritin levels (median 1469 vs. 1229; p=0.024) among them. Evaluation of CT features showed that COVID-19 pneumonia pattern (p<0.001) and pulmonary angiopathy (p<0.001) were significantly more profound among the PTE cohort. To note, the most proximal pulmonary thrombosis was located in the segmental (n=3, 2.0%) and subsegmental pulmonary arteries (n=147, 98.0%). Also, the thrombosis predominantly occurred in bilateral lungs with multilobar involvement (n=95, 63.3%). CONCLUSION: Overall, PTE disease remains prevalent among COVID-19 patients despite timely administration of thromboprophylactic therapy. The presence of hyperinflammatory activities, unique thrombotic locations as well as concurrent pulmonary parenchyma and vasculature aberrations in our PTE cohort implicate immunothrombosis as the principal mechanism of this novel phenomenon. We strongly recommend future researchers to elucidate this important clinical disease among our post- COVID vaccination populations.


Assuntos
COVID-19 , Pneumopatias , Embolia Pulmonar , Trombose , Humanos , COVID-19/complicações , COVID-19/diagnóstico por imagem , Centros de Atenção Terciária , Estudos Retrospectivos , Estudos Transversais , Neovascularização Patológica , Circulação Pulmonar , Embolia Pulmonar/diagnóstico por imagem , Embolia Pulmonar/etiologia , Tomografia Computadorizada por Raios X/métodos
7.
Med J Malaysia ; 78(2): 241-249, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36988537

RESUMO

INTRODUCTION: Time is the greatest challenge in stroke management. This study aimed to examine factors contributing to prehospital delay and decision delay among stroke patients. MATERIALS AND METHODS: A cross-sectional study involving acute stroke patients admitted to Seri Manjung Hospital was conducted between August 2019 and October 2020 via faceto- face interview. Prehospital delay was defined as more than 120 minutes taken from recognition of stroke symptoms till arrival in hospital, while decision delay was defined as more than 60 minutes taken from recognition of stroke symptoms till decision was made to seek treatment. RESULTS: The median prehospital delay of 102 enrolled patients was 364 minutes (IQR 151.5, 1134.3) while the median for decision delay was 120 minutes (IQR 30.0, 675.0). No history of stroke (adj. OR 4.15; 95% CI 1.21, 14.25; p=0.024) and unaware of thrombolysis service (adj. OR 17.12; 95% CI 1.28, 229.17; p=0.032) were associated with higher odds of prehospital delay, while Indian ethnicity (adj. OR 0.09; 95% CI 0.02, 0.52; p=0.007) was associated with lower odds of prehospital delay as compared to Malay ethnicity. On the other hand, higher National Institutes of Health Stroke Scale (NIHSS) score (adj. OR 0.86; 95% CI 0.78, 0.95; p=0.002) was associated with lower odds of decision delay. CONCLUSION: Public awareness is crucial to shorten prehosital delay and decision delay for better patients' outcomes in stroke. Various public health campaigns are needed to improve the awareness for stroke.


Assuntos
Serviços Médicos de Emergência , Acidente Vascular Cerebral , Humanos , Malásia , Hospitais de Distrito , Estudos Transversais , Fatores de Tempo , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia
8.
Nat Commun ; 14(1): 981, 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36813785

RESUMO

Lifetime-encoded materials are particularly attractive as optical tags, however examples are rare and hindered in practical application by complex interrogation methods. Here, we demonstrate a design strategy towards multiplexed, lifetime-encoded tags via engineering intermetallic energy transfer in a family of heterometallic rare-earth metal-organic frameworks (MOFs). The MOFs are derived from a combination of a high-energy donor (Eu), a low-energy acceptor (Yb) and an optically inactive ion (Gd) with the 1,2,4,5 tetrakis(4-carboxyphenyl) benzene (TCPB) organic linker. Precise manipulation of the luminescence decay dynamics over a wide microsecond regime is achieved via control over metal distribution in these systems. Demonstration of this platform's relevance as a tag is attained via a dynamic double encoding method that uses the braille alphabet, and by incorporation into photocurable inks patterned on glass and interrogated via digital high-speed imaging. This study reveals true orthogonality in encoding using independently variable lifetime and composition, and highlights the utility of this design strategy, combining facile synthesis and interrogation with complex optical properties.

9.
J Cancer Res Clin Oncol ; 149(8): 5085-5094, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36334155

RESUMO

PURPOSE: Systemic-inflammatory response parameters (SIR) are known prognostic markers in different tumour entities, but have not been evaluated in patients with iCCA treated with systemic chemotherapy. Therefore, we evaluated the impact of different SIR markers on the clinical course of patients with advanced iCCA treated at our center. METHODS: SIR markers were retrospectively evaluated in 219 patients with iCCA at the West-German-Cancer-Center Essen from 2014 to 2019. Markers included neutrophil/lymphocyte ratio (NLR), lymphocyte/monocyte ratio (LMR), CRP, and the modified Glasgow-Prognostic-Score (mGPS), which were correlated with clinico-pathological findings, response to chemotherapy (ORR), progression-free (PFS) and overall survival (OS) using Kaplan-Meier analyses, and Cox proportional models. RESULTS: Median overall survival (OS) of the entire cohort was 14.8 months (95% CI 11.2-24.4). Median disease-free survival (DFS) in 81 patients undergoing resection was 12.3 months (95% CI 9.7-23.1). The median OS from start of palliative CTX (OSpall) was 10.9 months (95% 9.4-14.6). A combined Systemic Inflammatory Score (SIS) comprising all evaluated SIR markers correlated significantly with ORR, PFS, and OSpall. Patients with a high SIS (≥ 2) vs. SIS 0 had a significantly inferior OSpall (HR 8.7 95% CI 3.71-20.38, p < 0.001). Multivariate analysis including known prognostic markers (ECOG, CA19-9, LDH, and N- and M-status) identified the SIS as an independent prognostic factor. CONCLUSIONS: Inflammatory markers associate with inferior survival outcomes in patients with iCCA. A simple SIS may guide treatment decisions in patients treated with systemic chemotherapy.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Humanos , Prognóstico , Estudos Retrospectivos , Inflamação/patologia , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/patologia , Linfócitos/patologia , Ductos Biliares Intra-Hepáticos , Neoplasias dos Ductos Biliares/tratamento farmacológico , Neoplasias dos Ductos Biliares/patologia
10.
J Biochem Mol Toxicol ; 36(10): e23174, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35861662

RESUMO

Respiratory diseases (RDs), such as chronic obstructive pulmonary disease, cystic fibrosis, asthma, and pneumonia, are associated with significant morbidity and mortality. Treatment usually consists of antibiotics and steroids. Relevant published literature reviews, studies, and clinical trials were accessed from institutional and electronic databases. The keywords used were respiratory diseases, steroids, antibiotics, and combination of steroids and antibiotics. Selected articles and literature were carefully reviewed. Antibiotics are often prescribed as the standard therapy to manage RDs. Types of causative respiratory pathogens, spectrum of antibiotics activity, route of administration, and course of therapy determine the type of antibiotics that are prescribed. Despite being associated with good clinical outcome, treatment failure and recurrence rate are still high. In addition, antibiotic resistance has been widely reported due to bacterial mutations in response to the use of antibiotics, which render them ineffective. Nevertheless, there has been a growing demand for corticosteroids (CS) and antibiotics to treat a wide variety of diseases, including various airway diseases, due to their immunosuppressive and anti-inflammatory properties. The use of CS is well established and there are different formulations based on the diseases, such as topical administration, tablets, intravenous injections, and inhaled preparations. Both antibiotics and CS possess similar properties in terms of their anti-inflammatory effects, especially regulating cytokine release. Thus, the current review examines and discusses the different applications of antibiotics, CS, and their combination in managing various RDs. Drawbacks of these interventions are also discussed.


Assuntos
Antibacterianos , Esteroides , Corticosteroides/uso terapêutico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Inflamatórios , Citocinas , Esteroides/uso terapêutico
11.
Nurse Educ Today ; 112: 105330, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35303543

RESUMO

BACKGROUND: Smoking is an important modifiable risk factor of morbidities and mortality. Although healthcare professionals play an important role in smoking cessation, their adoption of such practices is relatively low because of inadequate training. To address this issue, we incorporated a service-learning model to operate the Youth Quitline. Undergraduate nursing students were trained and received supervision while delivering smoking cessation counseling through the Youth Quitline as their clinical placement. OBJECTIVES: We evaluated the effectiveness of the placement by assessing students' knowledge, attitudes and practices regarding smoking cessation and tobacco control. DESIGN: One-group pretest-posttest design. SETTING: Youth Quitline. PARTICIPANTS: A total of 61 third-year students in a mental health nursing program. METHODS: Students were required to complete 80 h at the Youth Quitline. The 80 h were divided into 20 sessions; students used four sessions to approach and recruit youth smokers in the community, then provided them with telephone counseling for the rest of the time. Prior to the placement, students attended a 2-day workshop. The outcomes were changes in students' knowledge, attitudes and practices regarding smoking cessation and tobacco control 3 months after the placement compared with baseline. RESULTS: From January-June 2021, students conducted 105 outreach activities to identify 3142 smokers in the community, and provided telephone counseling for 336 smokers via Youth Quitline. Compared with baseline, significant improvements were observed in students' knowledge, attitudes and practices regarding smoking cessation and tobacco control at 3-month follow-up. CONCLUSIONS: The clinical placement improved students' knowledge, attitudes and practices regarding smoking cessation and tobacco control, enhancing their competency in providing support to assist smokers to quit in their future practice. Incorporating the service-learning model in existing community-based services can provide additional venues for nursing students to practice. This is particularly important because many venues have restricted access during the COVID-19 pandemic.


Assuntos
COVID-19 , Bacharelado em Enfermagem , Abandono do Hábito de Fumar , Estudantes de Enfermagem , Adolescente , Aconselhamento , Atenção à Saúde , Humanos , Pandemias , Abandono do Hábito de Fumar/psicologia
12.
ACS Nano ; 16(2): 2399-2406, 2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35138803

RESUMO

Advances in epitaxy have enabled the preparation of high-quality material architectures consisting of incommensurate components. Remote epitaxy based on lattice transparency of atomically thin graphene has been intensively studied for cost-effective advanced device manufacturing and heterostructure formation. However, remote epitaxy on nongraphene two-dimensional (2D) materials has rarely been studied even though it has a broad and immediate impact on various disciplines, such as many-body physics and the design of advanced devices. Herein, we report remote epitaxy of ZnO on monolayer MoS2 and the realization of a whispering-gallery-mode (WGM) cavity composed of a single crystalline ZnO nanorod and monolayer MoS2. Cross-sectional transmission electron microscopy and first-principles calculations revealed that the nongraphene 2D material interacted with overgrown and substrate layers and also exhibited lattice transparency. The WGM cavity embedding monolayer MoS2 showed enhanced luminescence of MoS2 and multimodal emission.

13.
ACS Appl Mater Interfaces ; 14(2): 3038-3047, 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-34995439

RESUMO

Optical anticounterfeiting tags utilize the photoluminescent properties of materials to encode unique patterns, enabling identification and validation of important items and assets. These tags must combine optical complexity with ease of production and authentication to both prevent counterfeiting and to remain practical for widespread use. Metal-organic frameworks (MOFs) based on polynuclear, rare earth clusters are ideal materials platforms for this purpose, combining fine control over structure and composition, with tunable, complex energy transfer mechanisms via both linker and metal components. Here we report the design and synthesis of a set of heterometallic MOFs based on combinations of Eu, Nd, and Yb with the tetratopic linker 1,3,6,8-tetrakis(4-carboxyphenyl)pyrene. The energetics of this linker facilitate the intentional concealment of the visible emissions from Eu while retaining the infrared emissions of Nd and Yb, creating an optical tag with multiple covert elements. Unique to the materials system reported herein, we document the occurrence of a previously not observed 11-metal cluster correlated with the presence of Yb in the MOFs, coexisting with a commonly encountered 9-metal cluster. We demonstrate the utility of these materials as intricate optical tags with both rapid and in-depth screening techniques, utilizing orthogonal identifiers across composition, emission spectra, and emission decay dynamics. This work highlights the important effect of linker selection in controlling the resulting photoluminescent properties in MOFs and opens an avenue for the targeted design of highly complex, multifunctional optical tags.

14.
Nano Lett ; 21(23): 9930-9938, 2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34797671

RESUMO

Recent advances in emerging atomically thin transition metal dichalcogenide semiconductors with strong light-matter interactions and tunable optical properties provide novel approaches for realizing new material functionalities. Coupling two-dimensional semiconductors with all-dielectric resonant nanostructures represents an especially attractive opportunity for manipulating optical properties in both the near-field and far-field regimes. Here, by integrating single-layer WSe2 and titanium oxide (TiO2) dielectric metasurfaces with toroidal resonances, we realized robust exciton emission enhancement over 1 order of magnitude at both room and low temperatures. Furthermore, we could control exciton dynamics and annihilation by using temperature to tailor the spectral overlap of excitonic and toroidal resonances, allowing us to selectively enhance the Purcell effect. Our results provide rich physical insight into the strong light-matter interactions in single-layer TMDs coupled with toroidal dielectric metasurfaces, with important implications for optoelectronics and photonics applications.

15.
Malays J Pathol ; 43(2): 333-336, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34448798

RESUMO

Salmonella intracranial infection is infrequently encountered in clinical practice. However, with prompt intervention and appropriate antimicrobial therapy, the outcome is usually favourable. A 56-year-old gentleman who worked as an organic fertilizer production supervisor underwent tumour resection for meningioma located at the left frontal temporoparietal region. The surgical procedure went smoothly, and he has prescribed dexamethasone thereafter. He was discharged well. However, a few days after that he developed a fever associated with pus discharged from the surgical wound. A computed tomography (CT) scan of the brain was performed and it revealed an abscess located at the left frontal temporoparietal subdural and subgaleal regions with adjacent cerebritis. Another craniotomy was done to drain the abscess. The bacterial culture of the pus specimen grew Salmonella Enteritidis. The bacterium was susceptible to ciprofloxacin, ceftriaxone, and amoxicillin-clavulanic acid. Clinical improvement was evident after surgical intervention with an additional 6 weeks of ceftriaxone therapy.


Assuntos
Abscesso Encefálico , Neoplasias Meníngeas , Meningioma , Infecções por Salmonella , Abscesso Encefálico/etiologia , Ceftriaxona , Craniotomia/efeitos adversos , Humanos , Masculino , Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Pessoa de Meia-Idade , Salmonella enteritidis
16.
Nanomaterials (Basel) ; 11(8)2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34443922

RESUMO

Recent advances in nanoscience have opened ways of recycling substrates for nanomaterial growth. Novel materials, such as atomically thin materials, are highly desirable for the recycling substrates. In this work, we report recycling of monolayer graphene as a growth template for synthesis of single crystalline ZnO nanowires. Selective nucleation of ZnO nanowires on graphene was elucidated by scanning electron microscopy and density functional theory calculation. Growth and subsequent separation of ZnO nanowires was repeated up to seven times on the same monolayer graphene film. Raman analyses were also performed to investigate the quality of graphene structure along the recycling processes. The chemical robustness of graphene enables the repetitive ZnO nanowire growth without noticeable degradation of the graphene quality. This work presents a route for graphene as a multifunctional growth template for diverse nanomaterials such as nanocrystals, aligned nanowires, other two-dimensional materials, and semiconductor thin films.

17.
N Engl J Med ; 384(6): 497-511, 2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-33264556

RESUMO

BACKGROUND: World Health Organization expert groups recommended mortality trials of four repurposed antiviral drugs - remdesivir, hydroxychloroquine, lopinavir, and interferon beta-1a - in patients hospitalized with coronavirus disease 2019 (Covid-19). METHODS: We randomly assigned inpatients with Covid-19 equally between one of the trial drug regimens that was locally available and open control (up to five options, four active and the local standard of care). The intention-to-treat primary analyses examined in-hospital mortality in the four pairwise comparisons of each trial drug and its control (drug available but patient assigned to the same care without that drug). Rate ratios for death were calculated with stratification according to age and status regarding mechanical ventilation at trial entry. RESULTS: At 405 hospitals in 30 countries, 11,330 adults underwent randomization; 2750 were assigned to receive remdesivir, 954 to hydroxychloroquine, 1411 to lopinavir (without interferon), 2063 to interferon (including 651 to interferon plus lopinavir), and 4088 to no trial drug. Adherence was 94 to 96% midway through treatment, with 2 to 6% crossover. In total, 1253 deaths were reported (median day of death, day 8; interquartile range, 4 to 14). The Kaplan-Meier 28-day mortality was 11.8% (39.0% if the patient was already receiving ventilation at randomization and 9.5% otherwise). Death occurred in 301 of 2743 patients receiving remdesivir and in 303 of 2708 receiving its control (rate ratio, 0.95; 95% confidence interval [CI], 0.81 to 1.11; P = 0.50), in 104 of 947 patients receiving hydroxychloroquine and in 84 of 906 receiving its control (rate ratio, 1.19; 95% CI, 0.89 to 1.59; P = 0.23), in 148 of 1399 patients receiving lopinavir and in 146 of 1372 receiving its control (rate ratio, 1.00; 95% CI, 0.79 to 1.25; P = 0.97), and in 243 of 2050 patients receiving interferon and in 216 of 2050 receiving its control (rate ratio, 1.16; 95% CI, 0.96 to 1.39; P = 0.11). No drug definitely reduced mortality, overall or in any subgroup, or reduced initiation of ventilation or hospitalization duration. CONCLUSIONS: These remdesivir, hydroxychloroquine, lopinavir, and interferon regimens had little or no effect on hospitalized patients with Covid-19, as indicated by overall mortality, initiation of ventilation, and duration of hospital stay. (Funded by the World Health Organization; ISRCTN Registry number, ISRCTN83971151; ClinicalTrials.gov number, NCT04315948.).


Assuntos
Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Antivirais/uso terapêutico , Tratamento Farmacológico da COVID-19 , Hidroxicloroquina/uso terapêutico , Interferon beta-1a/uso terapêutico , Lopinavir/uso terapêutico , Monofosfato de Adenosina/uso terapêutico , Idoso , Alanina/uso terapêutico , Antivirais/administração & dosagem , Antivirais/efeitos adversos , COVID-19/mortalidade , Quimioterapia Combinada , Feminino , Mortalidade Hospitalar , Hospitalização , Humanos , Análise de Intenção de Tratamento , Estimativa de Kaplan-Meier , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Respiração Artificial , Falha de Tratamento
18.
Angew Chem Int Ed Engl ; 60(3): 1203-1211, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33137241

RESUMO

Optical tags provide a way to quickly and unambiguously identify valuable assets. Current tag fluorophore options lack the tunability to allow combined methods of encoding in a single material. Herein we report a design strategy to encode multilayer complexity in a family of heterometallic rare-earth metal-organic frameworks based on highly connected nonanuclear clusters. To impart both intricacy and security, a synergistic approach was implemented resulting in both overt (visible) and covert (near-infrared, NIR) properties, with concomitant multi-emissive spectra and tunable luminescence lifetimes. Tag authentication is validated with a variety of orthogonal detection methodologies. Importantly, the effect induced by subtle compositional changes on intermetallic energy transfer, and thus on the resulting photophysical properties, is demonstrated. This strategy can be widely implemented to create a large library of highly complex, difficult-to-counterfeit optical tags.

20.
Med J Malaysia ; 75(6): 649-654, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33219172

RESUMO

BACKGROUND AND OBJECTIVE: Physical and behavioural problems from extended usage of electronic devices are issues among primary school children. This study is aimed to investigate the prevalence of physical and behavioural complaints arising from the electronic device usage and to identify the potential factors that predicted the complaints. METHODS: This was a primary school-based cross-sectional study using multistage cluster sampling, conducted at Bau district in Sarawak, Malaysia in 40 primary schools. A questionnaire was used to collect information of usage pattern in insufficient lighting, timing and position. The physical and behavioural complaints were traced. Data analysis was performed using SPSS version 22. A p-value < 0.05 with 95% CI was considered as statistically significant. RESULTS: About 52.8% of the 569 students used digital devices in a bright room, 69.8% in the day time and 54.4% in sitting position. The physical complaints were headache (32.9%), neck, shoulder and back pain (32.9%) followed by by eye strain (31.8%). Regarding behavioural problems, 25.7% of the students had loss of interest in study and outdoor activities (20.7%), skipped meals (19.0%) and arguments/disagreements with parents (17.9%). After logistic regression analysis, the lying position (OR=1.71, 95% CI: 1.096, 2.688) and darkroom lighting (OR=2.323 95% CI: 1.138, 4.744) appeared to be potential predictors of the complaint. CONCLUSION: One-quarter of the students studied experienced physical complaints, and one-fifth had behavioural problems associated with the use of electronic devices. Lying position and darkroom lighting are the potential predictors of complaints. Therefore, we suggest that the children should use electronic devices in the sitting position with adequate room lighting.


Assuntos
Instituições Acadêmicas , Tempo de Tela , Criança , Estudos Transversais , Humanos , Prevalência , Estudantes , Inquéritos e Questionários
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