Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 47
Filtrar
1.
BMC Cancer ; 24(1): 379, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38528478

RESUMO

BACKGROUND: Multiple studies have indicated that patients with high body mass index (BMI) may have favourable survival outcomes following treatment with an immune checkpoint inhibitor (ICI). However, this evidence is limited by several factors, notably the minimal evidence from randomised controlled trials (RCTs), the use of categorised BMI with inconsistent cut point definitions, and minimal investigation of contemporary combination ICI therapy. Moreover, whether overweight and obese patients gain a larger benefit from contemporary frontline chemoimmunotherapy in non-small cell lung cancer (NSCLC) is unclear. METHODS: This secondary analysis pooled individual patient data from the intention-to-treat population of the IMpower130 and IMpower150 RCTs comparing chemoimmunotherapy versus chemotherapy. Co-primary outcomes were overall survival (OS) and progression-free survival (PFS). The potentially non-linear relationship between BMI and chemoimmunotherapy treatment effect was evaluated using Multivariable Fractional Polynomial Interaction (MFPI). As a sensitivity analysis, chemoimmunotherapy treatment effect (chemoimmunotherapy versus chemotherapy) on survival was also estimated for each BMI subgroup defined by World Health Organisation classification. Exploratory analyses in the respective chemoimmunotherapy and chemotherapy cohort were undertaken to examine the survival outcomes among BMI subgroups. RESULTS: A total of 1282 patients were included. From the MFPI analysis, BMI was not significantly associated with chemoimmunotherapy treatment effect with respect to either OS (p = 0.71) or PFS (p = 0.35). This was supported by the sensitivity analyses that demonstrated no significant treatment effect improvement in OS/PFS among overweight or obese patients compared to normal weight patients (OS: normal BMI HR = 0.74 95% CI 0.59-0.93, overweight HR = 0.78 95% CI 0.61-1.01, obese HR = 0.84 95% CI 0.59-1.20). Exploratory analyses further highlighted that survival outcomes were not significantly different across BMI subgroups in either the chemoimmunotherapy therapy cohort (Median OS: normal BMI 19.9 months, overweight 17.9 months, and obese 19.5 months, p = 0.7) or the chemotherapy cohort (Median OS: normal 14.1 months, overweight 15.9 months, and obese 16.7 months, p = 0.7). CONCLUSION: There was no association between high BMI (overweight or obese individuals) and enhanced chemoimmunotherapy treatment benefit in front-line treatment of advanced non-squamous NSCLC. This contrasts with previous publications that showed a superior treatment benefit in overweight and obese patients treated with immunotherapy given without chemotherapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Índice de Massa Corporal , Sobrepeso , Obesidade/complicações , Imunoterapia
2.
Oncologist ; 28(4): e205-e211, 2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-36905578

RESUMO

BACKGROUND: Monotherapy immune checkpoint inhibitor (ICI) used in second- or later-line settings has been reported to induce hyperprogression. This study evaluated hyperprogression risk with ICI (atezolizumab) in the first-, second-, or later-line treatment of advanced non-small cell lung cancer (NSCLC), and provides insights into hyperprogression risk with contemporary first-line ICI treatment. METHODS: Hyperprogression was identified using Response Evaluation Criteria in Solid Tumours (RECIST)-based criteria in a dataset of pooled individual-participant level data from BIRCH, FIR, IMpower130, IMpower131, IMpower150, OAK, and POPLAR trials. Odds ratios were computed to compare hyperprogression risks between groups. Landmark Cox proportional-hazard regression was used to evaluate the association between hyperprogression and progression-free survival/overall survival. Secondarily, putative risk factors for hyperprogression among second- or later-line atezolizumab-treated patients were evaluated using univariate logistic regression models. RESULTS: Of the included 4644 patients, 119 of the atezolizumab-treated patients (n = 3129) experienced hyperprogression. Hyperprogression risk was markedly lower with first-line atezolizumab-either chemoimmunotherapy or monotherapy-compared to second/later-line atezolizumab monotherapy (0.7% vs. 8.8%, OR = 0.07, 95% CI, 0.04-0.13). Further, there was no statistically significant difference in hyperprogression risk with first-line atezolizumab-chemoimmunotherapy versus chemotherapy alone (0.6% vs. 1.0%, OR = 0.55, 95% CI, 0.22-1.36). Sensitivity analyses using an extended RECIST-based criteria including early death supported these findings. Hyperprogression was associated with worsened overall survival (HR = 3.4, 95% CI, 2.7-4.2, P < .001); elevated neutrophil-to-lymphocyte ratio was the strongest risk factor for hyperprogression (C-statistic = 0.62, P < .001). CONCLUSIONS: This study presents first evidence for a markedly lower hyperprogression risk in advanced NSCLC patients treated with first-line ICI, particularly with chemoimmunotherapy, as compared to second- or later-line ICI treatment.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Progressão da Doença , Inibidores de Checkpoint Imunológico/efeitos adversos , Neoplasias Pulmonares/patologia , Intervalo Livre de Progressão
3.
Parasitol Res ; 122(1): 1-10, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36434314

RESUMO

There has been increasing interest in the study of Blastocystis in the last two decades. Many studies have been carried out in human and animal hosts including environmental sources, but there is little or no information on the occurrence of Blastocystis in water sources worldwide. Therefore, this study aimed at assessing the occurrence of Blastocystis in water sources across the world from 2005 to 2022, noting the method of detection and the distribution of the subtypes from various water sources. A literature search was performed on internet-based databases including Google search, PubMed, Scopus, and Web of Science. Upon application of the criteria for inclusion, 25 articles revealing the occurrence of Blastocystis in water sources in 15 countries were included in the review. Blastocystis occurrence varies across water sources ranging from 0% in a drinking water source in Venezuela to 100% in rivers; well water, stored water, and fishpond in Nepal and Malaysia; and fountain water, irrigation water, and rainwater in Italy, Spain, and Thailand. The occurrence of the parasite was significantly associated with the coliform count, temperature, conductivity, dissolved oxygen, turbidity, total dissolved solids, and chemical oxygen demand. A total of 11 Blastocystis subtypes were identified in water sources worldwide, namely, ST1-ST8, ST10, ST23, and ST26 in which ST1 and ST3 were the most prevalent subtypes. Considering the importance of Blastocystis as a waterborne parasite, the subtype distribution and morphological distinction in water sources need to be carried out using molecular and electron microscopic techniques. Existing studies have covered only about 10% of the world's countries.


Assuntos
Infecções por Blastocystis , Blastocystis , Animais , Humanos , Infecções por Blastocystis/epidemiologia , Infecções por Blastocystis/parasitologia , Água , Fezes/parasitologia , Malásia , Filogenia , Variação Genética , Prevalência
4.
J Gambl Stud ; 39(4): 1537-1546, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37544961

RESUMO

Betting on the various codes of football in Australia accounts for the majority of sports betting, with Australian rules football (AFL) by far the most popular sport in Australia. Several studies have revealed the heavy presence of gambling advertising during AFL broadcasts, and a frequently used advertising strategy involves the use of well-known AFL commentators outlining their tips and betting suggestions. To date, no research has examined the hypotheses that skill may help in predicting AFL matches and monetary outcomes from AFL betting. Rather than merely discounting such ideas, it is important to test them empirically. The aims of this study were therefore, to examine if (1) expert AFL tipsters made better predictions than random picks, (2) expert AFL tipsters gained greater monetary reward than random selection, and (3) expert tipsters' prediction accuracy improved with betting experience. To this end, six seasons of AFL matches, odds data, and expert tipster data were analysed retrospectively, totalling 1141 matches. Random selections were calculated for each match using an inbuilt random number generator within Microsoft Excel and a $2 simulated wager was applied for each AFL match. The results of mixed-effects modelling showed that experts picked more correct outcomes than random selection; experts' correct predictions were partially mediated by home-game selections; no difference in monetary outcome was observed for experts compared to random selection; experts' predictions did not improve over time. The results of this study may be used to inform both psychological interventions that target gamblers' illusions of control, and public health gambling harm prevention messaging.


Assuntos
Jogo de Azar , Humanos , Jogo de Azar/psicologia , Estudos Retrospectivos , Austrália , Esportes de Equipe
5.
Eur Phys J E Soft Matter ; 44(2): 25, 2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33751249

RESUMO

The droplet rolling angle is one of the important indicators to measure the coating's hydrophobic performance, but the specific factors affecting the droplet rolling angle on the micro-nanostructured superhydrophobic coating surface are not yet known. Based on the rolling mechanism of droplets on rough surfaces, and from the perspective of coating microscopic energy conservation, this paper points out that the micron-scale morphology and the nanoscale morphology can comprehensively affect the droplet rolling angle. From the above perspective, a mathematical model of the droplet rolling angle on the micro-nanostructure superhydrophobic coating surface was established. The model shows that the droplet rolling angle is positively correlated with the ratio of nano-sized pillar width to spacing, the ratio of micron-sized papilla radius to spacing, and the liquid-gas interfacial tension, and is negatively correlated to the droplet intrinsic contact angle, droplet volume and droplet density. The droplet rolling angle calculated by the presented model is in good agreement with the experimentally tested results. This model can provide good accuracy in predicting the droplet rolling angle on the micro-nanostructured superhydrophobic coating surface.

6.
J Therm Biol ; 74: 14-22, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29801619

RESUMO

Heat shock response (HSR), in terms of transcription regulation of two heat shock proteins genes hsp70 and hsp90), was analysed in a widespread tropical copepod Pseudodiaptomus annandalei. The mRNA transcripts of both genes were quantified after copepods at a salinity of 20 underwent an acclimation process involving an initial acclimation temperature of 29 °C, followed by gradual thermal ramping to the target exposure temperature range of 24-36 °C. The respective cellular HSR and organismal metabolism, measured by respiratory activity at exposure temperatures, were compared. The fold change in mRNA expression for both hsp70 and hsp90 (8-9 fold) peaks at 32 °C, which is very close to 32.4 °C, the upper thermal optimum for respiration in the species. Unexpectedly, the modelled HSR curves peak at only 3 °C (hsp90) and 3.5 °C (hsp70) above the mean water temperature (29.32 °C) of the copepod in the field. We propose that copepods in tropical waters adopt a preparative HSR strategy, early at the upper limit of its thermal optimum, due to the narrow thermal range of its habitat thus precluding substantial energy demand at higher temperatures. However, the model suggests that the species could survive to at least 36 °C with short acclimation time. Nevertheless, the significant overlap between its thermal range of hsp synthesis and the narrow temperature range of its habitat also suggests that any unprecedented rise in sea temperature would have a detrimental effect on the species.


Assuntos
Aclimatação , Copépodes/metabolismo , Resposta ao Choque Térmico , Estresse Fisiológico , Temperatura , Animais , Estuários , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , RNA Mensageiro/metabolismo , Clima Tropical
7.
BMC Bioinformatics ; 16 Suppl 18: S4, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26678287

RESUMO

BACKGROUND: Copepods are planktonic organisms that play a major role in the marine food chain. Studying the community structure and abundance of copepods in relation to the environment is essential to evaluate their contribution to mangrove trophodynamics and coastal fisheries. The routine identification of copepods can be very technical, requiring taxonomic expertise, experience and much effort which can be very time-consuming. Hence, there is an urgent need to introduce novel methods and approaches to automate identification and classification of copepod specimens. This study aims to apply digital image processing and machine learning methods to build an automated identification and classification technique. RESULTS: We developed an automated technique to extract morphological features of copepods' specimen from captured images using digital image processing techniques. An Artificial Neural Network (ANN) was used to classify the copepod specimens from species Acartia spinicauda, Bestiolina similis, Oithona aruensis, Oithona dissimilis, Oithona simplex, Parvocalanus crassirostris, Tortanus barbatus and Tortanus forcipatus based on the extracted features. 60% of the dataset was used for a two-layer feed-forward network training and the remaining 40% was used as testing dataset for system evaluation. Our approach demonstrated an overall classification accuracy of 93.13% (100% for A. spinicauda, B. similis and O. aruensis, 95% for T. barbatus, 90% for O. dissimilis and P. crassirostris, 85% for O. similis and T. forcipatus). CONCLUSIONS: The methods presented in this study enable fast classification of copepods to the species level. Future studies should include more classes in the model, improving the selection of features, and reducing the time to capture the copepod images.


Assuntos
Copépodes/fisiologia , Redes Neurais de Computação , Animais , Automação , Bases de Dados Factuais , Análise Discriminante , Processamento de Imagem Assistida por Computador
8.
Pain Manag Nurs ; 16(4): 552-60, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26256219

RESUMO

Breakthrough pain is a significant contributor to much suffering by patients. The experience of intense pain may interfere with, and affect, daily life functioning and has major consequences on patients' well-being if it is not well managed. The area of breakthrough pain has not been fully understood. This study thus aimed to explore the experiences of breakthrough pain among palliative patients. A qualitative study based on a series of open-ended interviews among 21 palliative patients suffering from pain at an urban tertiary hospital in Malaysia was conducted. Five themes were generated: (i) pain viewed as an unbearable experience causing misery in the lives of patients, (ii) deterioration of body function and no hope of recovery, (iii) receiving of inadequate pain management for pain, (iv) insensitivity of healthcare providers toward patients' pain experience, and (v) pain coping experiences of patients. The findings revealed that nonpharmacologic approaches such as psychosocial support should be introduced to the patients. Proper guidance and information should be given to healthcare providers to improve the quality of patient care. Healthcare providers should adopt a sensitive approach in caring for patients' needs. The aim is to meet the needs of the patients who want to be pain free or to attain adequate relief of their pain for breakthrough pain.


Assuntos
Dor Irruptiva/terapia , Dor do Câncer/terapia , Manejo da Dor , Cuidados Paliativos , Satisfação do Paciente , Adulto , Dor Irruptiva/psicologia , Dor do Câncer/psicologia , Feminino , Humanos , Malásia , Masculino , Pessoa de Meia-Idade , Medição da Dor , Pesquisa Qualitativa
9.
JMIR Res Protoc ; 13: e50417, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38381495

RESUMO

BACKGROUND: Antimicrobial stewardship programs attempting to optimize antibiotic therapy and clinical outcomes mainly focus on inpatient and outpatient settings. The lack of antimicrobial stewardship program studies in the emergency department (ED) represents a gap in tackling the problem of antimicrobial resistance as EDs treat a substantial number of upper respiratory tract infection cases throughout the year. OBJECTIVE: We intend to implement two evidence-based interventions: (1) patient education and (2) providing physician feedback on their prescribing rates. We will incorporate evidence from a literature review and contextualizing the interventions based on findings from a local qualitative study. METHODS: Our study uses a quasi-experimental design to evaluate the effects of interventions over time in the EDs of 4 public hospitals in Singapore. We will include an initial control period of 18 months. In the next 6 months, we will randomize 2 EDs to receive 1 intervention (ie, patient education) and the other 2 EDs to receive the alternative intervention (ie, physician feedback). All EDs will receive the second intervention in the subsequent 6 months on top of the ongoing intervention. Data will be collected for another 6 months to assess the persistence of the intervention effects. The information leaflets will be handed to patients at the EDs before they consult with the physician, while feedback to individual physicians by senior doctors is in the form of electronic text messages. The feedback will contain the physicians' antibiotic prescribing rate compared with the departments' overall antibiotic prescribing rate and a bite-size message on good antibiotic prescribing practices. RESULTS: We will analyze the data using segmented regression with difference-in-difference estimation to account for concurrent cluster comparisons. CONCLUSIONS: Our proposed study assesses the effectiveness of evidence-based, context-specific interventions to optimize antibiotic prescribing in EDs. These interventions are aligned with Singapore's national effort to tackle antimicrobial resistance and can be scaled up if successful. TRIAL REGISTRATION: ClinicalTrials.gov NCT05451863; https://clinicaltrials.gov/study/NCT05451836. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/50417.

10.
Antimicrob Resist Infect Control ; 12(1): 24, 2023 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-36991475

RESUMO

BACKGROUND: The COVID-19 pandemic has changed the epidemiology of upper respiratory tract infections (URTI) and the disease profile of patients attending the emergency department (ED). Hence, we sought to explore the changes in ED physicians' attitudes and behaviours in four EDs in Singapore. METHODS: We employed a sequential mixed-methods approach (quantitative survey followed by in-depth interviews). Principal component analysis was performed to derive latent factors, followed by multivariable logistic regression to explore the independent factors associated with high antibiotic prescribing. Interviews were analysed using the deductive-inductive-deductive framework. We derive five meta-inferences by integrating the quantitative and qualitative findings with an explanatory bidirectional framework. RESULTS: We obtained 560 (65.9%) valid responses from the survey and interviewed 50 physicians from various work experiences. ED physicians were twice as likely to report high antibiotic prescribing rates pre-COVID-19 pandemic than during the pandemic (AOR = 2.12, 95% CI 1.32 to 3.41, p = 0.002). Five meta-inferences were made by integrating the data: (1) Less pressure to prescribe antibiotics due to reduced patient demand and more patient education opportunities; (2) A higher proportion of ED physicians self-reported lower antibiotic prescribing rates during the COVID-19 pandemic but their perception of the overall outlook on antibiotic prescribing rates varied; (3) Physicians who were high antibiotic prescribers during the COVID-19 pandemic made less effort for prudent antibiotic prescribing as they were less concerned about antimicrobial resistance; (4) the COVID-19 pandemic did not change the factors that lowered the threshold for antibiotic prescribing; (5) the COVID-19 pandemic did not change the perception that the public's knowledge of antibiotics is poor. CONCLUSIONS: Self-reported antibiotic prescribing rates decreased in the ED during the COVID-19 pandemic due to less pressure to prescribe antibiotics. The lessons and experiences learnt from the COVID-19 pandemic can be incorporated into public and medical education in the war against antimicrobial resistance going forward. Antibiotic use should also be monitored post-pandemic to assess if the changes are sustained.


Assuntos
COVID-19 , Médicos , Humanos , Antibacterianos/uso terapêutico , Pandemias , Padrões de Prática Médica
11.
J Glob Antimicrob Resist ; 33: 89-96, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36906173

RESUMO

OBJECTIVES: Pre-COVID-19 pandemic, patients who attended the emergency department (ED) for upper respiratory tract infection (URTI) were more likely to receive antibiotics if they expected them. These expectations could have changed with the change in health-seeking behaviour during the pandemic. We assessed the factors associated with antibiotics expectation and receipt for uncomplicated URTI patients in four Singapore EDs during the COVID-19 pandemic. METHODS: We conducted a cross-sectional study on adult patients with URTI from March 2021 to March 2022 in four Singapore EDs and assessed the determinants of antibiotics expectation and receipt using multivariable logistic regression models. We also assessed the reasons patients expect antibiotics during their ED visit. RESULTS: Among 681 patients, 31.0% expected antibiotics while 8.7% received antibiotics during their ED visit. Factors (adjusted odds ratio [95% confidence interval]) that significantly influenced expectation for antibiotics include: 1) prior consultation for current illness with (6.56 [3.30-13.11]) or without (1.50 [1.01-2.23]) antibiotics prescribed; 2) anticipation for COVID-19 test (1.56 [1.01-2.41]); and 3) poor (2.16 [1.26-3.68]) to moderate (2.26 [1.33-3.84]) knowledge on antibiotics use and resistance. Patients expecting antibiotics were 10.6 times (10.64 [5.34-21.17]) more likely to receive antibiotics. Those with tertiary education were twice (2.20 [1.09-4.43]) as likely to receive antibiotics. CONCLUSION: In conclusion, patients with URTI who expected antibiotics to be prescribed remained more likely to receive it during the COVID-19 pandemic. This highlights the need for more public education on the non-necessity for antibiotics for URTI and COVID-19 to address the problem of antibiotic resistance.


Assuntos
COVID-19 , Infecções Respiratórias , Adulto , Humanos , Motivação , Pandemias , Infecções Respiratórias/tratamento farmacológico , Antibacterianos/uso terapêutico , Estudos Transversais , Inquéritos e Questionários , Serviço Hospitalar de Emergência
12.
Front Public Health ; 11: 1250658, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38074705

RESUMO

Background: The uncertainties surrounding the COVID-19 pandemic led to a surge in non-urgent emergency department (ED) attendance among people presenting with upper respiratory tract infection (URTI) symptoms. These non-urgent visits, often manageable in primary care, exacerbated ED overcrowding, which could compromise the quality of ED services. Understanding patients' expectations and the reasons for these ED visits is imperative to mitigate the problem of ED overcrowding. Hence, we assessed the factors influencing patients' expectations for diagnostic tests during their ED visits for uncomplicated URTI during different phases of the pandemic. Methods: We conducted a cross-sectional study on adults with URTI symptoms seeking care at four public EDs in Singapore between March 2021 and March 2022. We segmented the study period into three COVID-19 pandemic phases-containment, transition, and mitigation. The outcome variables are whether patients expected (1) a COVID-19-specific diagnostic test, (2) a non-COVID-19-specific diagnostic test, (3) both COVID-19-specific and non-COVID-19-specific diagnostic tests, or (4) no diagnostic test. We built a multinomial regression model with backward stepwise selection and classified the findings according to Andersen's healthcare utilization model. Results: The mean age of participants was 34.5 (12.7) years. Factors (adjusted odds ratio [95% confidence interval]) influencing expectations for a COVID-19-specific diagnostic test in the ED include younger age {21-40 years: (2.98 [1.04-8.55])}, no prior clinical consultation (2.10 [1.13-3.89]), adherence to employer's health policy (3.70 [1.79-7.67]), perceived non-severity of illness (2.50 [1.39-4.55]), being worried about contracting COVID-19 (2.29 [1.11-4.69]), and during the transition phase of the pandemic (2.29 [1.15-4.56]). Being non-employed influenced the expectation for non-COVID-19-specific diagnostic tests (3.83 [1.26-11.66]). Factors influencing expectations for both COVID-19-specific and non-COVID-19-specific tests include younger age {21-40 years: (3.61 [1.26-10.38]); 41-60 years: (4.49 [1.43-14.13])}, adherence to employer's health policy (2.94 [1.41-6.14]), being worried about contracting COVID-19 (2.95 [1.45- 5.99]), and during the transition (2.03 [1.02-4.06]) and mitigation (2.02 [1.03-3.97]) phases of the pandemic. Conclusion: Patients' expectations for diagnostic tests during ED visits for uncomplicated URTI were dynamic across the COVID-19 pandemic phases. Expectations for COVID-19-specific diagnostic tests for ED visits for uncomplicated URTI were higher among younger individuals and those worried about contracting COVID-19 during the COVID-19 pandemic. Future studies are required to enhance public communications on the availability of diagnostic services in primary care and public education on self-management of emerging infectious diseases such as COVID-19.


Assuntos
COVID-19 , Adulto , Humanos , Adulto Jovem , COVID-19/diagnóstico , COVID-19/epidemiologia , Pandemias , Motivação , Estudos Transversais , Serviço Hospitalar de Emergência , Aceitação pelo Paciente de Cuidados de Saúde , Testes Diagnósticos de Rotina , Teste para COVID-19
13.
Front Public Health ; 10: 1067575, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36703815

RESUMO

Background and objectives: The high transmissibility of SARS-CoV-2 has exposed weaknesses in our infection control and detection measures, particularly in healthcare settings. Aerial sampling has evolved from passive impact filters to active sampling using negative pressure to expose culture substrate for virus detection. We evaluated the effectiveness of an active air sampling device as a potential surveillance system in detecting hospital pathogens, for augmenting containment measures to prevent nosocomial transmission, using SARS-CoV-2 as a surrogate. Methods: We conducted air sampling in a hospital environment using the AerosolSenseTM air sampling device and compared it with surface swabs for their capacity to detect SARS-CoV-2. Results: When combined with RT-qPCR detection, we found the device provided consistent SARS-CoV-2 detection, compared to surface sampling, in as little as 2 h of sampling time. The device also showed that it can identify minute quantities of SARS-CoV-2 in designated "clean areas" and through a N95 mask, indicating good surveillance capacity and sensitivity of the device in hospital settings. Conclusion: Active air sampling was shown to be a sensitive surveillance system in healthcare settings. Findings from this study can also be applied in an organism agnostic manner for surveillance in the hospital, improving our ability to contain and prevent nosocomial outbreaks.


Assuntos
COVID-19 , Infecção Hospitalar , Humanos , SARS-CoV-2 , COVID-19/diagnóstico , COVID-19/epidemiologia , COVID-19/prevenção & controle , Hospitais , Controle de Infecções , Infecção Hospitalar/prevenção & controle
14.
Chemosphere ; 263: 128272, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297216

RESUMO

Barnacles are ubiquitous in coastal ecosystems of different geographical regions worldwide. This is the first study attempting to assess the suitability of barnacles as bioindicators of persistent organic pollutants (POPs) in coastal environments. Barnacles were collected from the coasts around Peninsular Malaysia and analyzed for POPs including polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and organochlorine pesticides (OCPs). Among POPs, PCBs showed the highest concentrations with elevated contributions of CB28 and CB153. As for PBDEs, BDE47 was the most frequently detected congener, while BDE209 was detected in barnacles from two stations in Port Klang and the levels reached up to >70% of total PBDE concentrations. Concentrations of OCPs detected in barnacles were in the order of CHLs > DDTs > HCHs > HCB and 4,4'-DDE and cis- and trans-chlordane were the predominant OCP compounds. A comparison with previous studies in Malaysia showed consistent levels of POPs. Green mussels collected from selected barnacles' habitats, for the sake of a comparison, showed almost similar profiles but lower concentrations of POPs. The spatial distribution of POPs observed in barnacles and comparison of POP levels and profiles with mussels indicated that barnacles can be useful bioindicators for monitoring POPs contamination in the coastal ecosystems.


Assuntos
Hidrocarbonetos Clorados , Praguicidas , Bifenilos Policlorados , Thoracica , Animais , Ecossistema , Biomarcadores Ambientais , Monitoramento Ambiental , Éteres Difenil Halogenados/análise , Hidrocarbonetos Clorados/análise , Malásia , Poluentes Orgânicos Persistentes , Praguicidas/análise , Bifenilos Policlorados/análise
15.
Front Immunol ; 12: 694759, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335606

RESUMO

Background: Transmission blocking vaccines targeting the sexual-stages of the malaria parasite could play a major role to achieve elimination and eradication of malaria. The Plasmodium falciparum Pfs25 protein (Pfs25) is the most clinically advanced candidate sexual-stage antigen. IMX313, a complement inhibitor C4b-binding protein that forms heptamers with the antigen fused to it, improve antibody responses. This is the first time that viral vectors have been used to induce antibodies in humans against an antigen that is expressed only in the mosquito vector. Methods: Clinical trial looking at safety and immunogenicity of two recombinant viral vectored vaccines encoding Pfs25-IMX313 in healthy malaria-naive adults. Replication-deficient chimpanzee adenovirus serotype 63 (ChAd63) and the attenuated orthopoxvirus modified vaccinia virus Ankara (MVA), encoding Pfs25-IMX313, were delivered by the intramuscular route in a heterologous prime-boost regimen using an 8-week interval. Safety data and samples for immunogenicity assays were taken at various time-points. Results: The reactogenicity of the vaccines was similar to that seen in previous trials using the same viral vectors encoding other antigens. The vaccines were immunogenic and induced both antibody and T cell responses against Pfs25, but significant transmission reducing activity (TRA) was not observed in most volunteers by standard membrane feeding assay. Conclusion: Both vaccines were well tolerated and demonstrated a favorable safety profile in malaria-naive adults. However, the transmission reducing activity of the antibodies generated were weak, suggesting the need for an alternative vaccine formulation. Trial Registration: Clinicaltrials.gov NCT02532049.


Assuntos
Imunogenicidade da Vacina , Vacinas Antimaláricas/administração & dosagem , Malária Falciparum/prevenção & controle , Plasmodium falciparum/imunologia , Vacinas Sintéticas/administração & dosagem , Anticorpos Antiprotozoários/sangue , Células Cultivadas , Inglaterra , Voluntários Saudáveis , Humanos , Imunização , Vacinas Antimaláricas/efeitos adversos , Vacinas Antimaláricas/imunologia , Malária Falciparum/imunologia , Malária Falciparum/parasitologia , Malária Falciparum/transmissão , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/parasitologia , Fatores de Tempo , Vacinas Sintéticas/efeitos adversos , Vacinas Sintéticas/imunologia
16.
Environ Sci Pollut Res Int ; 27(19): 23643-23654, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32297113

RESUMO

Dust particles suspended in the atmosphere have been a big headache for electric power transmission industry in China. As transmission lines pass through dusty or air-polluted areas, dust contaminants are likely to deposit and accumulate on line insulators, which is one of the greatest causes of flashover and failure of power transmission. To study the statistical characteristics of this type of contamination, dust samples were collected and measured, and a physical model was set up to explain the deposition and accumulation mechanism of the particles. The trajectories of particles were tracked using fluid mechanics and contact mechanics, and an adhesion criterion was proposed. Simulation software was then applied to validate the model; further different environmental factors were studied that would affect the particle size distribution. The results show that under natural contamination conditions, the particle size distribution on the surface of the insulator shows a certain concentration at size ranges 1~100 µm and basically obeys a log-normal distribution. In addition, relative humidity, air velocity, and the charge accumulated on the surface all have significant influences on particle size distribution characteristics, while the effect of the electric field is mainly reflected in the difference in the number concentration of particle adhesion.


Assuntos
Poluentes Atmosféricos/análise , Poeira/análise , Atmosfera , China , Monitoramento Ambiental , Tamanho da Partícula
17.
Lancet Digit Health ; 2(5): e240-e249, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-33328056

RESUMO

BACKGROUND: Deep learning is a novel machine learning technique that has been shown to be as effective as human graders in detecting diabetic retinopathy from fundus photographs. We used a cost-minimisation analysis to evaluate the potential savings of two deep learning approaches as compared with the current human assessment: a semi-automated deep learning model as a triage filter before secondary human assessment; and a fully automated deep learning model without human assessment. METHODS: In this economic analysis modelling study, using 39 006 consecutive patients with diabetes in a national diabetic retinopathy screening programme in Singapore in 2015, we used a decision tree model and TreeAge Pro to compare the actual cost of screening this cohort with human graders against the simulated cost for semi-automated and fully automated screening models. Model parameters included diabetic retinopathy prevalence rates, diabetic retinopathy screening costs under each screening model, cost of medical consultation, and diagnostic performance (ie, sensitivity and specificity). The primary outcome was total cost for each screening model. Deterministic sensitivity analyses were done to gauge the sensitivity of the results to key model assumptions. FINDINGS: From the health system perspective, the semi-automated screening model was the least expensive of the three models, at US$62 per patient per year. The fully automated model was $66 per patient per year, and the human assessment model was $77 per patient per year. The savings to the Singapore health system associated with switching to the semi-automated model are estimated to be $489 000, which is roughly 20% of the current annual screening cost. By 2050, Singapore is projected to have 1 million people with diabetes; at this time, the estimated annual savings would be $15 million. INTERPRETATION: This study provides a strong economic rationale for using deep learning systems as an assistive tool to screen for diabetic retinopathy. FUNDING: Ministry of Health, Singapore.


Assuntos
Inteligência Artificial , Análise Custo-Benefício , Retinopatia Diabética/diagnóstico , Técnicas de Diagnóstico Oftalmológico/economia , Processamento de Imagem Assistida por Computador/economia , Modelos Biológicos , Telemedicina/economia , Adulto , Idoso , Árvores de Decisões , Diabetes Mellitus , Retinopatia Diabética/economia , Custos de Cuidados de Saúde , Humanos , Aprendizado de Máquina , Programas de Rastreamento/economia , Pessoa de Meia-Idade , Oftalmologia/economia , Fotografação , Exame Físico , Retina/patologia , Sensibilidade e Especificidade , Singapura , Telemedicina/métodos
18.
Polymers (Basel) ; 11(1)2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-30960119

RESUMO

In this study, glass fiber (GF)/phenol formaldehyde resin (PF)/epoxy resin (EP) three-phase electrical insulating composites were fabricated by selective laser sintering (SLS) additive manufacturing technology and subsequent infiltration. In the three-phase composites, glass fibers modified by a silane coupling agent (KH-550) were used as reinforcements, phenol formaldehyde resin acted as the binder and matrix, and infiltrated epoxy resin was the filler. Mechanical and electrical properties such as tensile strength, bending strength, dielectric constant, electrical conductivity, and electric breakdown strength of the GF/PF/EP three-phase composite parts were investigated. The results indicated that after being infiltrated with EP, the bending strength and tensile strength of the GF/PF/EP composites increased by 30% and 42.8%, respectively. Moreover, the flexural strength and tensile strength of the GF/PF/EP composite increased with the increase of the glass fiber content. More importantly, the three-phase composites showed high electrical properties. Significant improvement in the dielectric constant, electric breakdown strength, and resistivity with the increase in the content of glass fiber was observed. This enables the prepared GF/PF/EP composites to form complex structural electrical insulation devices by SLS, which expands the materials and applications of additive manufacturing technology.

20.
Carbohydr Polym ; 191: 79-85, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29661324

RESUMO

The chitosan/polyvinyl Alcohol/zeolite electrospun composite nanofibrous membrane was fabricated for adsorption of methyl orange. The EDX, TGA and tensile test were carried out for the characterization of the membrane. The Young's Modulus of the nanofibrous membranes increased by more than 100% with the addition of zeolite to chitosan/PVA. The batch adsorption tests were conducted by varying the initial concentration of methyl orange, contact time and pH of the dye solution. UV-vis results showed that most of the dye was adsorbed within 6 min. An adsorption kinetic study was carried out using the pseudo-second-order kinetic model, Lagergren-first-order model and intra particle diffusion model. The adsorption kinetics obeyed the Pseudo second order model. The adsorption mechanism was analyzed using the Langmuir and Freundlich isotherm model. The experimental data fits well with the Freundlich model. The adsorption capacity of the membrane was 153 mg/g. Adsorption capacity was decreased with increasing pH value. The resulting nanofiber became less active over methyl orange after several runs.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA