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1.
Clin Lab Med ; 44(3): 495-509, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39089754

RESUMO

Clinical flow cytometry plays a vital role in the diagnosis and monitoring of various red blood cell disorders. The high throughput, precision, and automation potential of this technique allows for cost-effective and timely analysis compared to older and more manual test methods. Flow cytometric analysis serves as the gold standard diagnostic method for multiple hematological disorders, especially in clinical scenarios where an assay needs to have high sensitivity, high specificity, and a short turnaround time. In this review, we discuss the role of flow cytometric analysis in paroxysmal nocturnal hemoglobinuria, fetal-maternal hemorrhage, and hereditary spherocytosis.


Assuntos
Citometria de Fluxo , Esferocitose Hereditária , Humanos , Citometria de Fluxo/métodos , Esferocitose Hereditária/diagnóstico , Esferocitose Hereditária/sangue , Eritrócitos/citologia , Hemoglobinúria Paroxística/diagnóstico , Hemoglobinúria Paroxística/sangue , Doenças Hematológicas/diagnóstico , Doenças Hematológicas/sangue , Gravidez , Feminino , Transfusão Feto-Materna/diagnóstico , Transfusão Feto-Materna/sangue
2.
Protein Sci ; 33(9): e5135, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39150232

RESUMO

Tardigrades are unique micro-organisms with a high tolerance to desiccation. The protection of their cells against desiccation involves tardigrade-specific proteins, which include the so-called cytoplasmic abundant heat soluble (CAHS) proteins. As a first step towards the design of peptides capable of mimicking the cytoprotective properties of CAHS proteins, we have synthesized several model peptides with sequences selected from conserved CAHS motifs and investigated to what extent they exhibit the desiccation-induced structural changes of the full-length proteins. Using circular dichroism spectroscopy, two-dimensional infrared spectroscopy, and molecular dynamics simulations, we have found that the CAHS model peptides are mostly disordered, but adopt a more α $$ \alpha $$ -helical structure upon addition of 2,2,2-trifluoroethanol, which mimics desiccation. This structural behavior is similar to that of full-length CAHS proteins, which also adopt more ordered conformations upon desiccation. We also have investigated the surface activity of the peptides at the air/water interface, which also mimics partial desiccation. Interestingly, sum-frequency generation spectroscopy shows that all model peptides are surface active and adopt a helical structure at the air/water interface. Our results suggest that amino acids with high helix-forming propensities might contribute to the propensity of these peptides to adopt a helical structure when fully or partially dehydrated. Thus, the selected sequences retain part of the CAHS structural behavior upon desiccation, and might be used as a basis for the design of new synthetic peptide-based cryoprotective materials.


Assuntos
Simulação de Dinâmica Molecular , Peptídeos , Tardígrados , Tardígrados/química , Animais , Peptídeos/química , Estrutura Secundária de Proteína , Sequência de Aminoácidos
3.
Pediatr Int ; 66(1): e15777, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38863264

RESUMO

BACKGROUND: We aimed to compare the clinical features and severity of the Omicron and Delta variant infections among children hospitalized for coronavirus disease 2019 (COVID-19). METHODS: Children 12 years old or less hospitalized for COVID-19 across five hospitals between January 1, 2021 and March 31, 2022 were identified using the state's pediatric COVID-19 registry. Delta and Omicron-infected patients without previous COVID-19 infection, COVID-19 vaccination, or co-infections were propensity-score matched 1:1 to control for differences in baseline characteristics. Clinical manifestations, treatments, and outcomes were analyzed. Disease severity was assessed using an adapted WHO ordinal scale. RESULTS: Of the initial 1367 patients, 668 had Delta infection and 699 had Omicron infection. Propensity-score matching produced 558 matched pairs. Patients with Omicron infection were more likely to present with croup (the odds ratio, OR, was 10.87, with a 95% confidence interval, CI, ranging from 2.54 to 46.59), lower respiratory tract infection (OR 2.32, 95% CI, 1.48-3.64) and seizures (OR 8.39, 95% CI, 5.04-13.99) compared with those with Delta infection. Omicron was associated with increased odds of moderate/severe disease (OR 6.14, 95% CI, 4.72-7.99) and a greater need for intravenous fluid therapy (OR 6.00, 95% CI, 4.29-8.39), corticosteroids (OR 3.08, 95% CI, 1.66-5.72), empirical antibiotics (OR 1.70, 95% CI, 1.10-2.64), and low-flow nasal oxygen therapy (OR 3.68, 95% CI, 2.17-6.22) in comparison with Delta. CONCLUSION: Children hospitalized with Omicron infection demonstrated a distinct clinical profile compared to those with Delta infection, with increased likelihood of moderate/severe disease and higher utilization of health-care resources.


Assuntos
COVID-19 , SARS-CoV-2 , Índice de Gravidade de Doença , Humanos , COVID-19/epidemiologia , Criança , Masculino , Feminino , Pré-Escolar , Lactente , Hospitalização/estatística & dados numéricos , Pontuação de Propensão , Estudos Retrospectivos , Sistema de Registros
4.
Cytometry B Clin Cytom ; 106(4): 282-293, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38721890

RESUMO

Multiparameter flow cytometry data is visually inspected by expert personnel as part of standard clinical disease diagnosis practice. This is a demanding and costly process, and recent research has demonstrated that it is possible to utilize artificial intelligence (AI) algorithms to assist in the interpretive process. Here we report our examination of three previously published machine learning methods for classification of flow cytometry data and apply these to a B-cell neoplasm dataset to obtain predicted disease subtypes. Each of the examined methods classifies samples according to specific disease categories using ungated flow cytometry data. We compare and contrast the three algorithms with respect to their architectures, and we report the multiclass classification accuracies and relative required computation times. Despite different architectures, two of the methods, flowCat and EnsembleCNN, had similarly good accuracies with relatively fast computational times. We note a speed advantage for EnsembleCNN, particularly in the case of addition of training data and retraining of the classifier.


Assuntos
Algoritmos , Citometria de Fluxo , Aprendizado de Máquina , Humanos , Citometria de Fluxo/métodos , Linfoma de Células B/classificação , Linfoma de Células B/diagnóstico , Linfoma de Células B/patologia , Linfócitos B/patologia , Linfócitos B/classificação , Linfócitos B/imunologia , Imunofenotipagem/métodos
5.
Artigo em Inglês | MEDLINE | ID: mdl-38816961

RESUMO

Clinical flow cytometry laboratories require quality control materials for assay development, validation, and performance monitoring, including new reagent lot qualification. However, finding suitable controls for populations with uncommonly expressed antigens or for rare populations, such as mast cells, can be difficult. To that end, we evaluated synthetic abnormal mast cell particles (SAMCP), developed together with, and manufactured by, Slingshot Biosciences. The SAMCP's were designed to phenotypically mimic abnormal neoplastic mast cells: they were customized to have the same light scatter and autofluorescence properties of mast cells, along with surface antigen levels of CD45, CD33, CD117, CD2, CD25, and CD30 consistent with that seen in mast cell disease. We evaluated several performance characteristics of these particles using ARUP's high sensitivity clinical mast cell assay, including limit of detection, off-target activity and FMO controls, precision, scatter properties of the particles utilizing several different cytometer platforms, and particle antigen stability. The phenotype of the SAMCP mimicked abnormal mast cells, and they could be distinguished from normal native mast cells. FMO controls demonstrated specificity of each of the markers, and no off-target binding was detected. The limit of detection of the particles spiked into normal bone marrow was found to be ≤0.003% in a limiting dilution assay. The mast cell particles were found to perform similarly on Becton Dickinson Lyric, Cytek Aurora, and Beckman Coulter Navios and CytoFLEX platforms. Within run and between run precision were less than 10% CV. SAMCP were stable up to 13 days with minimal loss of antigen fluorescence intensity. The SAMCP's were able to successfully mimic neoplastic mast cells based on the results of our high sensitivity mast cell flow cytometry panel. These synthetic cell particles represent an exciting and innovative technology, which can fulfill vital needs in clinical flow cytometry such as serving as standardized control materials for assay development and performance monitoring.

6.
Int J Mol Sci ; 25(7)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38612553

RESUMO

Mesenchymal stem/stromal cells (MSCs) are an extensively studied cell type in clinical trials due to their easy availability, substantial ex vivo proliferative capacity, and therapeutic efficacy in numerous pre-clinical animal models of disease. The prevailing understanding suggests that their therapeutic impact is mediated by the secretion of exosomes. Notably, MSC exosomes present several advantages over MSCs as therapeutic agents, due to their non-living nature and smaller size. However, despite their promising therapeutic potential, the clinical translation of MSC exosomes is hindered by an incomplete understanding of their biodistribution after administration. A primary obstacle to this lies in the lack of robust labels that are highly sensitive, capable of directly and easily tagging exosomes with minimal non-specific labeling artifacts, and sensitive traceability with minimal background noise. One potential candidate to address this issue is radioactive iodine. Protocols for iodinating exosomes and tracking radioactive iodine in live imaging are well-established, and their application in determining the biodistribution of exosomes has been reported. Nevertheless, the effects of iodination on the structural or functional activities of exosomes have never been thoroughly examined. In this study, we investigate these effects and report that these iodination methods abrogate CD73 enzymatic activity on MSC exosomes. Consequently, the biodistribution of iodinated exosomes may reflect the biodistribution of denatured exosomes rather than functionally intact ones.


Assuntos
Exossomos , Células-Tronco Mesenquimais , Neoplasias da Glândula Tireoide , Animais , Radioisótopos do Iodo , Distribuição Tecidual
7.
BMC Prim Care ; 25(1): 127, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654201

RESUMO

BACKGROUND: Considering time-consuming, cost-related limitations of laboratory-based HbA1c testing and follow-up clinic visits for diabetes management, it is important to explore alternative care models which incorporate point-of-care testing for HbA1c to monitor glycaemic control and related management. METHODS: Therefore, we adopted an implementation perspective to conduct one group pre- and post-intervention feasibility pilot assessing feasibility, acceptability and satisfaction with conducting home HbA1c test by patients with type 2 diabetes coupled with telemonitoring and teleconsultations (i.e., the Primary Technology Enhanced Care (PTEC) Home HbA1c Testing (HAT) Programme) in Singaporean primary care setting. The secondary objective was to compare the HbA1c, blood pressure and primary care visits at the end or during intervention, vs. 6 months before. Adult patients with type 2 diabetes with HbA1c ≤ 8% without any diabetes complications and having phone compatibility were recruited. Data was collected via patient self-reports and electronic medical records extraction. While summary statistics and paired t-test were computed for quantitative data, open-ended feedback was analysed using content analysis. RESULTS: A total of 33 participants completed the intervention out of 37 (33/37 = 89%) recruited from 73 eligible (37/73 = 51%). Most were either 51 to 60 years old (46.9%) or more than 60 years (37.5%), with more males (53.1%) and majority Chinese (93.8%). Majority (81.3%) felt that home HbA1c testing was beneficial with most commonly reported benefit of not having a clinic visit. A key finding was the average of diabetes-related visits being significantly lower post-intervention with comparable HbA1c values pre- and post-intervention. The most commonly reported challenge was using Bluetooth to transmit the reading (43.7%), followed by having too many steps to remember (28.1%). While participants reported being overall satisfied with the intervention, only 22% were willing to pay for it. CONCLUSION: Our findings support home HbA1c testing by patients coupled with telemonitoring and teleconsultations. Following are practical recommendations for the implementation scaling phase: offering PTEC HAT Programme to suitable patients who are self-motivated and have adequate digital literacy, provision of adequate educational and training support, sending reminders and exploring enabling manual submission of HbA1c readings considering Bluetooth-related challenges.


Assuntos
Diabetes Mellitus Tipo 2 , Hemoglobinas Glicadas , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/terapia , Estudos de Viabilidade , Hemoglobinas Glicadas/análise , Serviços de Assistência Domiciliar , Satisfação do Paciente , Projetos Piloto , Testes Imediatos , Atenção Primária à Saúde , Singapura , Telemedicina/métodos , Autoteste
8.
J Am Chem Soc ; 146(17): 11991-11999, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38639465

RESUMO

The complex dynamics and transience of assembly pathways in living systems complicate the understanding of these molecular to nanoscale processes. Current technologies are unable to track the molecular events leading to the onset of assembly, where real-time information is imperative to correlate their rich biology. Using a chemically designed pro-assembling molecule, we map its transformation into nanofibers and their fusion with endosomes to form hollow fiber clusters. Tracked by phasor-fluorescence lifetime imaging (phasor-FLIM) in epithelial cells (L929, A549, MDA-MB 231) and correlative light-electron microscopy and tomography (CLEM), spatiotemporal splicing of the assembly events shows time-correlated metabolic dysfunction. The biological impact begins with assembly-induced endosomal disruption that reduces glucose transport into the cells, which, in turn, stymies mitochondrial respiration.


Assuntos
Imagem Óptica , Humanos , Endossomos/metabolismo , Nanofibras/química , Linhagem Celular , Animais
9.
J Cachexia Sarcopenia Muscle ; 15(4): 1376-1387, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38646827

RESUMO

BACKGROUND: We aim to determine the multiethnic patterns of the prevalence and associated factors of poor muscle health and its associated components in older Chinese, Malays, and Indian Asian adults. METHODS: We included 2199 participants (mean age ± SD: 72.9 ± 8.3 years; 54.3% female) from the baseline assessment of the Population Health and Eye Disease Profile in Elderly Singaporeans (PIONEER; 2017-2022) cohort study. Poor muscle health was defined as the presence of either low muscle mass (DEXA), or low muscle strength (handgrip strength), or low physical performance (gait speed). Its components include poor muscle function (low muscle strength and/or low physical performance without low muscle mass), pre-sarcopenia (low muscle mass only), and any sarcopenia (low muscle mass with low muscle strength and/or low physical performance). Sociodemographic, clinical, and lifestyle factors were assessed using biochemistry, clinical tests, and validated questionnaires. Regression models were utilized to evaluate the independent risk factors of poor muscle health and its components. RESULTS: The national census-adjusted prevalence of poor muscle health (88%) was similar across the three ethnic groups. However, Chinese individuals had higher prevalence of pre-sarcopenia and any sarcopenia, and a lower prevalence of poor muscle function compared with Indians or Malays. We observed ethnic differences in modifiable risk factors (low physical activity, diabetes, osteoporosis, and obesity) of poor muscle health and its components. Although obesity was protective of pre-sarcopenia (RRR = 0.19, 95% CI: 0.11, 0.36) and any sarcopenia (RRR = 0.29, 95% CI: 0.18, 0.47) in the overall population and across ethnic groups, it was associated with 1.7 times (95% CI: 1.07, 2.67) the likelihood of poor muscle function in the entire population. CONCLUSIONS: Almost 90% of community dwelling Singaporean aged ≥60 years have poor muscle health across the three ethnic groups with ethnic disparities in modifiable risk factors, highlighting an urgent need for community-wide targeted interventions to promote muscle health.


Assuntos
Sarcopenia , Humanos , Feminino , Masculino , Idoso , Fatores de Risco , Prevalência , Sarcopenia/epidemiologia , Sarcopenia/etnologia , Singapura/epidemiologia , Povo Asiático , Idoso de 80 Anos ou mais , Força Muscular , Etnicidade/estatística & dados numéricos , Pessoa de Meia-Idade
10.
Neuroendocrinology ; 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38531329

RESUMO

Peptide-receptor radionuclide therapy (PRRT) is a targeted molecular therapy used to treat neuroendocrine tumours (NET). It has been shown to be effective and well-tolerated in patients with metastatic neuroendocrine tumours in several centres in United States (US), Europe and Australia. Tolerability and efficacy data emerging from Asian centres remain few. Epidemiological evidence suggests that there are differences in neuroendocrine neoplasms between the population groups. We aim to describe the treatment and safety outcomes of PRRT in the Asian population. Methods One hundred and seven (107) patients with metastatic neuroendocrine tumour who had undergone PRRT treatment from January 2012 to March 2019 were included in this retrospective study. The response rates using RECIST1.1 and qualitative analysis were examined. The overall and progression free survival curves were also evaluated. Results The median progression free survival was 49 months. Response assessment after completion of treatment showed that 33(37.9%) of 87 patients had partial or complete response. Subgroup analysis comparing high- and low-grade NET showed that there was a significant difference in the time to progression curves. Comparison of the number of cycles and progression free and overall survival also showed a significant difference. Ten patients (9%) had grade 3 or more haematological toxicities. Four patients (4%) had grade 3/4 hepatobiliary toxicities, although the presence of extensive liver metastases was a confounding factor. None of the patients had grade 3/4 acute kidney injury. Conclusion Our results show that PRRT is safe and effective in the treatment of metastatic neuroendocrine tumour in the Asian population. There was a significant difference in the progression free survival curves between low-grade and high-grade NET, and in the progression free and overall survival comparing the number of cycles received.

12.
Clin Respir J ; 18(3): e13747, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38529669

RESUMO

INTRODUCTION: Human metapneumovirus (hMPV) and respiratory syncytial virus (RSV) are significant contributors to the burden of acute respiratory infections in children, but data on hMPV from Southeast Asia are limited despite its potential for serious disease. This study aimed to compare the clinical presentation, resource utilisation and outcomes between hMPV and RSV infections in hospitalised Malaysian children. METHODS: This retrospective, observational study included children aged ≤12 years old hospitalised with hMPV or RSV, confirmed via direct fluorescent antibody (DFA) methods, between 1 July to 30 October 2022 at Hospital Tuanku Ja'afar Seremban, Malaysia. Demographic, clinical presentation, resource utilisation and outcome data were analysed. Propensity score matching was used to balance cohorts based on key demographic and clinical characteristics. RESULTS: This study included 192 patients, comprising 112 with hMPV and 80 with RSV. hMPV patients were older (median age 20.5 vs. 9.4 months, p < 0.001) and had a higher incidence of comorbidities (24.1% vs. 7.5%, p = 0.003). Fever was more common in the hMPV group (97.3% vs. 73.8%, p < 0.001), but the other clinical manifestations were similar. Postmatching analysis showed higher corticosteroid use in the hMPV group (p = 0.01). No significant differences were observed in the use of other resources, PICU admissions, duration of hospitalisation or mortality rates between both groups. CONCLUSION: hMPV and RSV infections in children share similar clinical manifestations and outcomes, with hMPV affecting older children and showing higher corticosteroid usage. These findings emphasise the need for equal clinical vigilance for both hMPV and RSV in paediatric respiratory infections.


Assuntos
Metapneumovirus , Infecções por Paramyxoviridae , Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Infecções Respiratórias , Humanos , Criança , Lactente , Adolescente , Adulto Jovem , Adulto , Infecções por Vírus Respiratório Sincicial/diagnóstico , Infecções por Vírus Respiratório Sincicial/epidemiologia , Infecções por Paramyxoviridae/diagnóstico , Infecções por Paramyxoviridae/epidemiologia , Estudos Retrospectivos , Pontuação de Propensão , Infecções Respiratórias/epidemiologia , Corticosteroides
13.
Cytometry B Clin Cytom ; 106(4): 228-238, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38407537

RESUMO

Flow cytometry is a key clinical tool in the diagnosis of many hematologic malignancies and traditionally requires close inspection of digital data by hematopathologists with expert domain knowledge. Advances in artificial intelligence (AI) are transferable to flow cytometry and have the potential to improve efficiency and prioritization of cases, reduce errors, and highlight fundamental, previously unrecognized associations with underlying biological processes. As a multidisciplinary group of stakeholders, we review a range of critical considerations for appropriately applying AI to clinical flow cytometry, including use case identification, low and high risk use cases, validation, revalidation, computational considerations, and the present regulatory frameworks surrounding AI in clinical medicine. In particular, we provide practical guidance for the development, implementation, and suggestions for potential regulation of AI-based methods in the clinical flow cytometry laboratory. We expect these recommendations to be a helpful initial framework of reference, which will also require additional updates as the field matures.


Assuntos
Inteligência Artificial , Citometria de Fluxo , Citometria de Fluxo/métodos , Citometria de Fluxo/normas , Humanos , Neoplasias Hematológicas/diagnóstico , Neoplasias Hematológicas/patologia
14.
Cancer Cell ; 42(3): 474-486.e12, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38402610

RESUMO

Chronic stress is associated with increased risk of metastasis and poor survival in cancer patients, yet the reasons are unclear. We show that chronic stress increases lung metastasis from disseminated cancer cells 2- to 4-fold in mice. Chronic stress significantly alters the lung microenvironment, with fibronectin accumulation, reduced T cell infiltration, and increased neutrophil infiltration. Depleting neutrophils abolishes stress-induced metastasis. Chronic stress shifts normal circadian rhythm of neutrophils and causes increased neutrophil extracellular trap (NET) formation via glucocorticoid release. In mice with neutrophil-specific glucocorticoid receptor deletion, chronic stress fails to increase NETs and metastasis. Furthermore, digesting NETs with DNase I prevents chronic stress-induced metastasis. Together, our data show that glucocorticoids released during chronic stress cause NET formation and establish a metastasis-promoting microenvironment. Therefore, NETs could be targets for preventing metastatic recurrence in cancer patients, many of whom will experience chronic stress due to their disease.


Assuntos
Armadilhas Extracelulares , Neoplasias Pulmonares , Humanos , Animais , Camundongos , Neutrófilos/patologia , Neoplasias Pulmonares/patologia , Pulmão/patologia , Microambiente Tumoral
16.
J Am Chem Soc ; 146(8): 5195-5203, 2024 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-38275287

RESUMO

Single-molecule localization microscopy (SMLM) is a powerful technique to achieve super-resolution imaging beyond the diffraction limit. Although various types of blinking fluorophores are currently considered for SMLM, intrinsic blinking fluorophores remain rare at the single-molecule level. Here, we report the synthesis of nanographene-based intrinsic burst-blinking fluorophores for highly versatile SMLM. We image amyloid fibrils in air and in various pH solutions without any additive and lysosome dynamics in live mammalian cells under physiological conditions. In addition, the single-molecule labeling of nascent proteins in primary sensory neurons was achieved with azide-functionalized nanographenes via click chemistry. SMLM imaging reveals higher local translation at axonal branching with unprecedented detail, while the size of translation foci remained similar throughout the entire network. These various results demonstrate the potential of nanographene-based fluorophores to drastically expand the applicability of super-resolution imaging.


Assuntos
Piscadela , Corantes Fluorescentes , Animais , Microscopia de Fluorescência/métodos , Corantes Fluorescentes/química , Imagem Individual de Molécula/métodos , Lisossomos/metabolismo , Mamíferos/metabolismo
17.
Angew Chem Int Ed Engl ; 63(18): e202314143, 2024 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-38179812

RESUMO

Drug safety and efficacy due to premature release into the bloodstream and poor biodistribution remains a problem despite seminal advances in this area. To circumvent these limitations, we report drug cyclization based on dynamic covalent linkages to devise a dual lock for the small-molecule anticancer drug, camptothecin (CPT). Drug activity is "locked" within the cyclic structure by the redox responsive disulfide and pH-responsive boronic acid-salicylhydroxamate and turns on only in the presence of acidic pH, reactive oxygen species and glutathione through traceless release. Notably, the dual-responsive CPT is more active (100-fold) than the non-cleavable (permanently closed) analogue. We further include a bioorthogonal handle in the backbone for functionalization to generate cyclic-locked, cell-targeting peptide- and protein-CPTs, for targeted delivery of the drug and traceless release in triple negative metastatic breast cancer cells to inhibit cell growth at low nanomolar concentrations.


Assuntos
Antineoplásicos , Nanopartículas , Neoplasias , Camptotecina/química , Distribuição Tecidual , Antineoplásicos/química , Micelas , Proteínas , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Liberação Controlada de Fármacos , Linhagem Celular Tumoral
18.
Q J Exp Psychol (Hove) ; 77(3): 551-562, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37114953

RESUMO

Illusory causation is a phenomenon in which people mistakenly perceive a causal relationship between a cue and outcome even though the contingency between them is actually zero. Illusory causation studies typically use a unidirectional causal rating scale, where one endpoint refers to no relationship and the other to a strongly positive causal relationship. This procedure may bias mean causal ratings in a positive direction, either by censoring negative ratings or by discouraging participants from giving the normative rating of zero which is at the bottom extreme of the scale. To test this possibility, we ran two experiments that directly compared the magnitude of causal illusions when assessed with a unidirectional (zero-positive) versus a bidirectional (negative-zero-positive) rating scale. Experiment 1 used high cue and outcome densities (both 75%), whereas Experiment 2 used neutral cue and outcome densities (both 50%). Across both experiments, we observed a larger illusory causation effect in the unidirectional group compared with the bidirectional group, despite both groups experiencing the same training trials. The causal illusions in Experiment 2 were observed despite participants accurately learning the conditional probabilities of the outcome occurring in both the presence and absence of the cue, suggesting that the illusion is driven by the inability to accurately integrate conditional probabilities to infer causal relationships. Our results indicate that although illusory causation is a genuine phenomenon that is observable with either a undirectional or a bidirectional rating scale, its magnitude may be overestimated when unidirectional rating scales are used.


Assuntos
Ilusões , Humanos , Aprendizagem , Causalidade , Probabilidade , Viés
19.
BMC Geriatr ; 23(1): 802, 2023 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-38053025

RESUMO

BACKGROUND: We explored the relationships between sarcopenia (SP), osteoporosis (OP), obesity (OB), (alone and in combination) with physical frailty (PF) in a multi-ethnic, population-based study of Asians aged ≥ 60 years. METHODS: Participants were enrolled from the PopulatION HEalth and Eye Disease PRofile in Elderly Singaporeans Study (PIONEER) study. PF was defined using the modified Fried phenotype; SP using the Asian Working Group for Sarcopenia 2019; OP using bone mineral density scores; and OB using the fat mass index. Modified Poisson regression models investigated the associations between exposures and PF, and the relative excess rates of PF due to interactions (RERI) to determine synergistic or antagonistic interactions. RESULTS: Of the 2643 participants, 54.8% was female; and 49.8%, 25.1%, 25.0% were Chinese, Indians, and Malays, respectively. 25%, 19.0% and 6.7% participants had OB only, SP only, and OP only, respectively. A total of 356 (17.5%), 151 (7.4%) and 97 (4.8%) had osteosarcopenia (OSP), sarcopenic obesity (SOB) and osteo-obesity (OOB), respectively; while 70 (3.5%) had all 3 morbid conditions (osteosarcopenic obesity, OSO). Both SP only and OB only were strongly associated with increased rates of PF (RR: 2.53, 95% CI: 1.95, 3.29; RR: 2.05, 95% CI: 1.58, 2.66 respectively); but not OP. Those with OSP, OOB and SOB were also associated with high risks of PF (RR: 2.82, 95% CI: 2.16, 3.68; RR: 2.34, 95% CI: 1.69, 3.23; and RR: 2.58, 95% CI: 1.95, 3.41, respectively) compared to robust individuals. Critically, individuals with OSO had the highest relative risk of having PF (RR: 3.06, CI: 2.28, 4.11). Only the sarcopenia-obesity interaction was significant, demonstrating negative synergism (antagonism). The concurrent presence of SP and OB was associated with a 100% lower rate of PF compared to the sum of the relatively rates of SP only and OB only. CONCLUSION: The prevalence of SP, OB and OP, alone and combined, is substantial in older Asians and their early identification is needed to mitigate the risk of frailty. OB may interact with SP in an antagonistic manner to moderate rates of frailty. Further longitudinal studies are needed to address causality and mechanistic underpinnings our findings.


Assuntos
Fragilidade , Osteoporose , Sarcopenia , Idoso , Humanos , Feminino , Sarcopenia/diagnóstico , Sarcopenia/epidemiologia , Sarcopenia/complicações , Fragilidade/diagnóstico , Fragilidade/epidemiologia , Fragilidade/complicações , Osteoporose/diagnóstico , Osteoporose/epidemiologia , Osteoporose/complicações , Densidade Óssea , Obesidade/diagnóstico , Obesidade/epidemiologia , Obesidade/complicações
20.
Pediatr Int ; 65(1): e15690, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38037505

RESUMO

BACKGROUND: We describe the epidemiology, clinical characteristics, and outcomes of multisystem inflammatory syndrome in children (MIS-C) among children from Negeri Sembilan, Malaysia. METHODS: A retrospective, multicentre, observational study was performed among children ≤15 years old who were hospitalized for MIS-C between January 18, 2021 and June 30, 2023. The incidence of MIS-C was estimated using reported SARS-CoV-2 cases and census population data. Descriptive analyses were used to summarize the clinical presentation and outcomes. RESULTS: The study included 53 patients with a median age of 5.7 years (IQR 1.8-8.7 years); 75.5% were males. The overall incidence of MIS-C was approximately 5.9 cases per 1,000,000 person-months. Pediatric intensive care unit (PICU) admission was required for 22 (41.5%) patients. No mortalities were recorded. Children aged 6-12 years were more likely to present with cardiac dysfunction/shock (odds ratio [OR] 5.43, 95% confidence interval [CI] 1.67-17.66), whereas children below 6 years were more likely to present with a Kawasaki disease phenotype (OR 5.50, 95% CI 1.33-22.75). Twenty patients (37.7%) presented with involvement of at least four organ systems, but four patients (7.5%) demonstrated single-organ system involvement. CONCLUSION: An age-based variation in the clinical presentation of MIS-C was demonstrated. Our findings suggest MIS-C could manifest in a spectrum, including single-organ involvement. Despite the high requirement for PICU admission, the prognosis of MIS-C was favorable, with no recorded mortalities.


Assuntos
COVID-19 , Síndrome de Resposta Inflamatória Sistêmica , Criança , Masculino , Humanos , Lactente , Pré-Escolar , Adolescente , Feminino , Estudos Retrospectivos , Síndrome de Resposta Inflamatória Sistêmica/diagnóstico , Síndrome de Resposta Inflamatória Sistêmica/epidemiologia , Síndrome de Resposta Inflamatória Sistêmica/terapia , COVID-19/epidemiologia , COVID-19/terapia , SARS-CoV-2
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