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1.
Circulation ; 148(24): e187-e280, 2023 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-37942682

RESUMO

The International Liaison Committee on Resuscitation engages in a continuous review of new, peer-reviewed, published cardiopulmonary resuscitation and first aid science. Draft Consensus on Science With Treatment Recommendations are posted online throughout the year, and this annual summary provides more concise versions of the final Consensus on Science With Treatment Recommendations from all task forces for the year. Topics addressed by systematic reviews this year include resuscitation of cardiac arrest from drowning, extracorporeal cardiopulmonary resuscitation for adults and children, calcium during cardiac arrest, double sequential defibrillation, neuroprognostication after cardiac arrest for adults and children, maintaining normal temperature after preterm birth, heart rate monitoring methods for diagnostics in neonates, detection of exhaled carbon dioxide in neonates, family presence during resuscitation of adults, and a stepwise approach to resuscitation skills training. Members from 6 International Liaison Committee on Resuscitation task forces have assessed, discussed, and debated the quality of the evidence, using Grading of Recommendations Assessment, Development, and Evaluation criteria, and their statements include consensus treatment recommendations. Insights into the deliberations of the task forces are provided in the Justification and Evidence-to-Decision Framework Highlights sections. In addition, the task forces list priority knowledge gaps for further research. Additional topics are addressed with scoping reviews and evidence updates.


Assuntos
Reanimação Cardiopulmonar , Serviços Médicos de Emergência , Parada Cardíaca Extra-Hospitalar , Nascimento Prematuro , Adulto , Feminino , Criança , Recém-Nascido , Humanos , Primeiros Socorros , Consenso , Parada Cardíaca Extra-Hospitalar/diagnóstico , Parada Cardíaca Extra-Hospitalar/terapia
2.
Circulation ; 146(25): e483-e557, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36325905

RESUMO

This is the sixth annual summary of the International Liaison Committee on Resuscitation International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations. This summary addresses the most recently published resuscitation evidence reviewed by International Liaison Committee on Resuscitation Task Force science experts. Topics covered by systematic reviews include cardiopulmonary resuscitation during transport; approach to resuscitation after drowning; passive ventilation; minimizing pauses during cardiopulmonary resuscitation; temperature management after cardiac arrest; use of diagnostic point-of-care ultrasound during cardiac arrest; use of vasopressin and corticosteroids during cardiac arrest; coronary angiography after cardiac arrest; public-access defibrillation devices for children; pediatric early warning systems; maintaining normal temperature immediately after birth; suctioning of amniotic fluid at birth; tactile stimulation for resuscitation immediately after birth; use of continuous positive airway pressure for respiratory distress at term birth; respiratory and heart rate monitoring in the delivery room; supraglottic airway use in neonates; prearrest prediction of in-hospital cardiac arrest mortality; basic life support training for likely rescuers of high-risk populations; effect of resuscitation team training; blended learning for life support training; training and recertification for resuscitation instructors; and recovery position for maintenance of breathing and prevention of cardiac arrest. Members from 6 task forces have assessed, discussed, and debated the quality of the evidence using Grading of Recommendations Assessment, Development, and Evaluation criteria and generated consensus treatment recommendations. Insights into the deliberations of the task forces are provided in the Justification and Evidence-to-Decision Framework Highlights sections, and priority knowledge gaps for future research are listed.


Assuntos
Reanimação Cardiopulmonar , Serviços Médicos de Emergência , Parada Cardíaca Extra-Hospitalar , Recém-Nascido , Criança , Humanos , Primeiros Socorros , Consenso , Parada Cardíaca Extra-Hospitalar/terapia , Tratamento de Emergência
3.
Environ Sci Technol ; 57(48): 19223-19235, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37933439

RESUMO

Insights into how biological systems respond to high- and low-dose acute environmental stressors are a fundamental aspect of exposome research. However, studying the impact of low-level environmental exposure in conventional in vitro settings is challenging. This study employed a three-dimensional (3D) biomimetic microfluidic lung-on-chip (µLOC) platform and RNA-sequencing to examine the effects of two model anthropogenic engineered nanoparticles (NPs): zinc oxide nanoparticles (Nano-ZnO) and copier center nanoparticles (Nano-CCP). The airway epithelium exposed to these NPs exhibited dose-dependent increases in cytotoxicity and barrier dysregulation (dominance of the external exposome). Interestingly, even nontoxic and low-level exposure (10 µg/mL) of the epithelium compartment to Nano-ZnO triggered chemotaxis of lung fibroblasts toward the epithelium. An increase in α smooth muscle actin (α-SMA) expression and contractile activity was also observed in these cells, indicating a bystander-like adaptive response (dominance of internal exposome). Further bioinformatics and network analysis showed that a low-dose Nano-ZnO significantly induced a robust transcriptomic response and upregulated several hub genes associated with the development of lung fibrosis. We propose that Nano-ZnO, even at a no observable effect level (NOEL) dose according to conventional standards, can function as a potent nanostressor to disrupt airway epithelium homeostasis. This leads to a cascade of profibrotic events in a cross-tissue compartment fashion. Our findings offer new insights into the early acute events of respiratory harm associated with environmental NPs exposure, paving the way for better exposomic understanding of this emerging class of anthropogenic nanopollutants.


Assuntos
Expossoma , Nanopartículas , Óxido de Zinco , Biomimética , Microfluídica , Nanopartículas/toxicidade , Fibroblastos , Óxido de Zinco/toxicidade
4.
Neuroradiology ; 64(1): 109-117, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34664112

RESUMO

PURPOSE: Rim lesions, characterised by a paramagnetic rim on susceptibility-based MRI, have been suggested to reflect chronic inflammatory demyelination in multiple sclerosis (MS) patients. Here, we assess, through susceptibility-weighted imaging (SWI), the prevalence, longitudinal volume evolution and clinical associations of rim lesions in subjects with early relapsing-remitting MS (RRMS). METHODS: Subjects (n = 44) with recently diagnosed RRMS underwent 3 T MRI at baseline (M0) and 1 year (M12) as part of a multi-centre study. SWI was acquired at M12 using a 3D segmented gradient-echo echo-planar imaging sequence. Rim lesions identified on SWI were manually segmented on FLAIR images at both time points for volumetric analysis. RESULTS: Twelve subjects (27%) had at least one rim lesion at M12. A linear mixed-effects model, with 'subject' as a random factor, revealed mixed evidence for the difference in longitudinal volume change between rim lesions and non-rim lesions (p = 0.0350 and p = 0.0556 for subjects with and without rim lesions, respectively). All 25 rim lesions identified showed T1-weighted hypointense signal. Subjects with and without rim lesions did not differ significantly with respect to age, disease duration or clinical measures of disability (p > 0.05). CONCLUSION: We demonstrate that rim lesions are detectable in early-stage RRMS on 3 T MRI across multiple centres, although their relationship to lesion enlargement is equivocal in this small cohort. Identification of SWI rims was subjective. Agreed criteria for defining rim lesions and their further validation as a biomarker of chronic inflammation are required for translation of SWI into routine MS clinical practice.


Assuntos
Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Encéfalo/diagnóstico por imagem , Imagem Ecoplanar , Humanos , Imageamento por Ressonância Magnética , Esclerose Múltipla Recidivante-Remitente/diagnóstico por imagem
5.
Arch Toxicol ; 96(5): 1455-1471, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35226136

RESUMO

The micronucleus (MN) assay is widely used as part of a battery of tests applied to evaluate the genotoxic potential of chemicals, including new food additives and novel food ingredients. Micronucleus assays typically utilise homogenous in vitro cell lines which poorly recapitulate the physiology, biochemistry and genomic events in the gut, the site of first contact for ingested materials. Here we have adapted and validated the MN endpoint assay protocol for use with complex 3D reconstructed intestinal microtissues; we have named this new protocol the reconstructed intestine micronucleus cytome (RICyt) assay. Our data suggest the commercial 3D microtissues replicate the physiological, biochemical and genomic responses of native human small intestine to exogenous compounds. Tissues were shown to maintain log-phase proliferation throughout the period of exposure and expressed low background MN. Analysis using the RICyt assay protocol revealed the presence of diverse cell types and nuclear anomalies (cytome) in addition to MN, indicating evidence for comprehensive DNA damage and mode(s) of cell death reported by the assay. The assay correctly identified and discriminated direct-acting clastogen, aneugen and clastogen requiring exogenous metabolic activation, and a non-genotoxic chemical. We are confident that the genotoxic response in the 3D microtissues more closely resembles the native tissues due to the inherent tissue architecture, surface area, barrier effects and tissue matrix interactions. This proof-of-concept study highlights the RICyt MN cytome assay in 3D reconstructed intestinal microtissues is a promising tool for applications in predictive toxicology.


Assuntos
Dano ao DNA , Micronúcleos com Defeito Cromossômico , Aneugênicos , Humanos , Testes para Micronúcleos/métodos , Mutagênicos/toxicidade
6.
Br J Neurosurg ; 36(4): 472-482, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35438022

RESUMO

BACKGROUND: Several studies have demonstrated music intervention as a safe and inexpensive option for reducing anxiety and pain perioperatively. We performed a systematic review to evaluate its possible benefit in perioperative neurosurgical management. METHODS: The following databases were searched with no restrictions on publication date: PubMed, Embase, CINAHL, PsycINFO, CENTRAL and ClinicalTrials.gov. All studies that quantitatively or qualitatively assessed the effects of any music-based intervention administered within one week of cranial or spinal neurosurgery were eligible. Meta-analysis could not be performed, and quantitative findings were instead summarised narratively. We then synthesised qualitative observations through thematic analysis before conducting an integrative review. PROSPERO registration: CRD42019152626. RESULTS: Seven studies, of sample sizes ranging from 8 to 60, were included, with the timing, duration, frequency and type of music intervention varying considerably across studies. Quantitative analysis involving five studies showed a significant decrease in anxiety following music intervention in four studies (p < 0.05), and reduced pain perception in three studies (p < 0.05). Mixed evidence was obtained for physiological outcomes including heart rate and blood pressure. Risk of bias was moderate to high. Quantitative findings were generally supported by qualitative analysis which provided additional insight into the factors influencing music intervention's effectiveness. CONCLUSION: Despite the heterogeneity in study characteristics, this review, which is the first mixed-methods systematic review assessing the effects of perioperative music intervention, not only reveals a potential role for music intervention in neurosurgery, but also highlights the possible importance of considering qualitative evidence in future studies to better characterise its effectiveness.


Assuntos
Musicoterapia , Música , Neurocirurgia , Ansiedade/prevenção & controle , Frequência Cardíaca/fisiologia , Humanos , Musicoterapia/métodos
7.
Curr Psychol ; : 1-16, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-35035200

RESUMO

With the record surge of positive cases in Southeast Asia, there is a need to examine the adverse mental effects of COVID-19 among the under-researched countries. This study aims to synthesize the extant literature reporting the effects of COVID-19 pandemic on the psychological outcomes of people in Southeast Asia, and its risk factors. A scoping review was adopted targeting articles published in PubMed, Google Scholar and Scopus from January 2020 to March 30, 2021. Articles were screened using predetermined eligibility criteria, resulting in 26 papers. Elevated prevalence of adverse mental effects was noted in most of the countries as the pandemic progressed over time, with Malaysia and Philippines reporting higher prevalence rates. Mental decline was found to be more profound among the general population compared to healthcare workers and students. Dominant risk factors reported were age (younger), sex (females), education (higher), low coping skill and social/family support, and poor reliability in COVID-19 related information. Adverse mental effects were noted among population, healthcare workers and students in most of the Southeast Asian countries. Intervention and prevention efforts should be based at community-level and prioritize young adults, females, and individuals with dire financial constraints.

8.
Circulation ; 142(16): e246-e261, 2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-32967446

RESUMO

Studies of pediatric cardiac arrest use inconsistent outcomes, including return of spontaneous circulation and short-term survival, and basic assessments of functional and neurological status. In 2018, the International Liaison Committee on Resuscitation sponsored the COSCA initiative (Core Outcome Set After Cardiac Arrest) to improve consistency in reported outcomes of clinical trials of adult cardiac arrest survivors and supported this P-COSCA initiative (Pediatric COSCA). The P-COSCA Steering Committee generated a list of potential survival, life impact, and economic impact outcomes and assessment time points that were prioritized by a multidisciplinary group of healthcare providers, researchers, and parents/caregivers of children who survived cardiac arrest. Then expert panel discussions achieved consensus on the core outcomes, the methods to measure those core outcomes, and the timing of the measurements. The P-COSCA includes assessment of survival, brain function, cognitive function, physical function, and basic daily life skills. Survival and brain function are assessed at discharge or 30 days (or both if possible) and between 6 and 12 months after arrest. Cognitive function, physical function, and basic daily life skills are assessed between 6 and 12 months after cardiac arrest. Because many children have prearrest comorbidities, the P-COSCA also includes documentation of baseline (ie, prearrest) brain function and calculation of changes after cardiac arrest. Supplementary outcomes of survival, brain function, cognitive function, physical function, and basic daily life skills are assessed at 3 months and beyond 1 year after cardiac arrest if resources are available.


Assuntos
Suporte Vital Cardíaco Avançado/normas , Reanimação Cardiopulmonar/métodos , Parada Cardíaca/diagnóstico , Avaliação de Resultados em Cuidados de Saúde/métodos , Humanos
9.
Circulation ; 142(16_suppl_1): S140-S184, 2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-33084393

RESUMO

This 2020 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations (CoSTR) for pediatric life support is based on the most extensive evidence evaluation ever performed by the Pediatric Life Support Task Force. Three types of evidence evaluation were used in this review: systematic reviews, scoping reviews, and evidence updates. Per agreement with the evidence evaluation recommendations of the International Liaison Committee on Resuscitation, only systematic reviews could result in a new or revised treatment recommendation. Systematic reviews performed for this 2020 CoSTR for pediatric life support included the topics of sequencing of airway-breaths-compressions versus compressions-airway-breaths in the delivery of pediatric basic life support, the initial timing and dose intervals for epinephrine administration during resuscitation, and the targets for oxygen and carbon dioxide levels in pediatric patients after return of spontaneous circulation. The most controversial topics included the initial timing and dose intervals of epinephrine administration (new treatment recommendations were made) and the administration of fluid for infants and children with septic shock (this latter topic was evaluated by evidence update). All evidence reviews identified the paucity of pediatric data and the need for more research involving resuscitation of infants and children.


Assuntos
Reanimação Cardiopulmonar/normas , Doenças Cardiovasculares/terapia , Serviços Médicos de Emergência/normas , Cuidados para Prolongar a Vida/normas , Corticosteroides/administração & dosagem , Arritmias Cardíacas/tratamento farmacológico , Atropina/administração & dosagem , Reanimação Cardiopulmonar/métodos , Criança , Humanos , Choque Séptico/tratamento farmacológico
10.
Clin Infect Dis ; 72(6): 1055-1058, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-32584975

RESUMO

Transmission risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in schools is unknown. Our investigations, especially in preschools, could not detect SARS-CoV-2 transmission despite screening of symptomatic and asymptomatic children. The data suggest that children are not the primary drivers of SARS-CoV-2 transmission in schools and could help inform exit strategies for lifting of lockdowns.


Assuntos
COVID-19 , SARS-CoV-2 , Criança , Pré-Escolar , Controle de Doenças Transmissíveis , Humanos , Programas de Rastreamento , Instituições Acadêmicas
11.
Nanotechnology ; 32(50)2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34536952

RESUMO

Liposomes are potential drug carriers for atherosclerosis therapy due to low immunogenicity and ease of surface modifications that allow them to have prolonged circulation half-life and specifically target atherosclerotic sites to increase uptake efficiency. However, the effects of their size, charge, and lipid compositions on macrophage and foam cell behaviour are not fully understood. In this study, liposomes of different sizes (60 nm, 100 nm and 180 nm), charges (-40 mV, -20 mV, neutral, +15 mV and +30 mV) and lipid compositions (1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine, L-a-phosphatidylcholine, and egg sphingomyelin) were synthesized, characterized and exposed to macrophages and foam cells. Compared to 100 nm neutral 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC) liposomes, flow cytometry and confocal imaging indicated that cationic liposomes and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DSPC) liposomes were internalized more by both macrophages and foam cells. Through endocytosis inhibition, phagocytosis and clathrin-mediated endocytosis were identified as the dominant mechanisms of uptake. Anionic and DSPC liposomes induced more cholesterol efflux capacity in foam cells. These results provide a guide for the optimal size, charge, and lipid composition of liposomes as drug carriers for atherosclerosis treatment.


Assuntos
Endocitose/efeitos dos fármacos , Lipossomos/farmacologia , Fagocitose/efeitos dos fármacos , 1,2-Dipalmitoilfosfatidilcolina/análogos & derivados , 1,2-Dipalmitoilfosfatidilcolina/química , Aterosclerose/tratamento farmacológico , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Colesterol/metabolismo , Células Espumosas/citologia , Células Espumosas/metabolismo , Humanos , Lipossomos/química , Lipossomos/uso terapêutico , Macrófagos/citologia , Macrófagos/metabolismo , Tamanho da Partícula , Propriedades de Superfície
12.
BMC Infect Dis ; 21(1): 644, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34225647

RESUMO

BACKGROUND: Available data on influenza burden across Southeast Asia are largely limited to pediatric populations, with inconsistent findings. METHODS: We conducted a multicenter, hospital-based active surveillance study of adults in Malaysia with community-acquired pneumonia (CAP), acute exacerbation of chronic obstructive pulmonary disease (AECOPD) and acute exacerbation of asthma (AEBA), who had influenza-like illness ≤10 days before hospitalization. We estimated the rate of laboratory-confirmed influenza and associated complications over 13 months (July 2018-August 2019) and described the distribution of causative influenza strains. We evaluated predictors of laboratory-confirmed influenza and severe clinical outcomes using multivariate analysis. RESULTS: Of 1106 included patients, 114 (10.3%) were influenza-positive; most were influenza A (85.1%), with A/H1N1pdm09 being the predominant circulating strain during the study following a shift from A/H3N2 from January-February 2019 onwards. In multivariate analyses, an absence of comorbidities (none versus any comorbidity [OR (95%CI), 0.565 (0.329-0.970)], p = 0.038) and of dyspnea (0.544 (0.341-0.868)], p = 0.011) were associated with increased risk of influenza positivity. Overall, 184/1106 (16.6%) patients were admitted to intensive care or high-dependency units (ICU/HDU) (13.2% were influenza positive) and 26/1106 (2.4%) died (2.6% were influenza positive). Males were more likely to have a severe outcome (ICU/HDU admission or death). CONCLUSIONS: Influenza was a significant contributor to hospitalizations associated with CAP, AECOPD and AEBA. However, it was not associated with ICU/HDU admission in this population. Study registration, NMRR ID: NMRR-17-889-35,174.


Assuntos
Asma/complicações , Infecções Comunitárias Adquiridas/complicações , Vírus da Influenza A Subtipo H3N2 , Influenza Humana/complicações , Pneumonia/complicações , Doença Pulmonar Obstrutiva Crônica/complicações , Adulto , Idoso , Pré-Escolar , Hospitalização , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade
13.
J Paediatr Child Health ; 57(9): 1460-1466, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33908109

RESUMO

AIM: We piloted a hand hygiene (HH) project in a ward, focusing on World Health Organization moments 1 and 4. Our aim was to design highly reliable interventions to achieve >90% compliance. METHODS: Baseline HH compliance was 57 and 67% for moments 1, 4, respectively, in 2015. After the pilot ward showed sustained improvement, we launched the 'HH bundle' throughout the hospital. This included: (i) appointment of HH champions; (ii) verbal/visual bedside reminders; (iii) patient empowerment; (iv) hand moisturisers; (v) tagging near-empty handrub (HR) bottles. Other hospital-wide initiatives included: (vi) Smartphone application for auditing; (vii) 'Speak up for Patient Safety' Campaign in 2017 for staff empowerment; (viii) making HH a key performance indicator. RESULTS: Overall HH compliance increased from a baseline median of 79.6-92.6% in end-2019. Moments 1 and 4 improved from 71 to 92.7% and from 77.6 to 93.2%, respectively. Combined HR and hand wash consumption increased from a baseline median of 82.6 ml/patient day (PD) to 109.2 mL/PD. Health-care-associated rotavirus infections decreased from a baseline median of 4.5 per 10 000 PDs to 1.5 per 10 000 PDs over time. CONCLUSIONS: The 'HH Bundle' of appointing HH champions, active reminders and feedback, patient education and empowerment, availability of hand moisturisers, tagging near-empty hand rub bottles together with hospital-wide initiatives including financial incentives and the 'Speak Up for Patient Safety' campaign successfully improved the overall HH compliance to >90%. These interventions were highly reliable, sustained over 4 years and also reduced health-care-associated rotavirus infection rates.


Assuntos
Infecção Hospitalar , Higiene das Mãos , Infecção Hospitalar/prevenção & controle , Fidelidade a Diretrizes , Desinfecção das Mãos , Pessoal de Saúde , Hospitais , Humanos , Controle de Infecções , Organização Mundial da Saúde
14.
Nanomedicine ; 37: 102434, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34214684

RESUMO

Atherosclerosis is a multifactorial disease triggered and sustained by risk factors such as high cholesterol, high blood pressure and unhealthy lifestyle. Inflammation plays a pivotal role in atherosclerosis pathogenesis. In this study, we developed a simvastatin (STAT) loaded nanoliposomal formulation (LIPOSTAT) which can deliver the drug into atherosclerotic plaque, when administered intravenously. This formulation is easily prepared, stable, and biocompatible with minimal burst release for effective drug delivery. 2D and 3D in vitro models were examined towards anti-inflammatory effects of STAT, both free and in combination with liposomes. LIPOSTAT induced greater cholesterol efflux in the 2D foam cells and significantly reduced inflammation in both 2D and 3D models. LIPOSTAT alleviated inflammation by reducing the secretion of early and late phase pro-inflammatory cytokines, monocyte adherence marker, and lipid accumulation cytokines. Additionally, the 3D foam cell spheroid model is a convenient and practical approach in testing various anti-atherosclerotic drugs without the need for human tissue.


Assuntos
Aterosclerose/tratamento farmacológico , Inflamação/tratamento farmacológico , Lipossomos/farmacologia , Nanopartículas/química , Sinvastatina/farmacologia , Aterosclerose/genética , Aterosclerose/patologia , Linhagem Celular , Sistemas de Liberação de Medicamentos/métodos , Células Espumosas/efeitos dos fármacos , Células Espumosas/patologia , Humanos , Inflamação/genética , Inflamação/patologia , Lipossomos/química , Placa Aterosclerótica/tratamento farmacológico , Placa Aterosclerótica/patologia , Sinvastatina/química , Esferoides Celulares/química , Esferoides Celulares/efeitos dos fármacos
15.
Int J Mol Sci ; 22(16)2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34445299

RESUMO

Deep partial-thickness burns damage most of the dermis and can cause severe pain, scarring, and mortality if left untreated. This study serves to evaluate the effectiveness of crosslinked keratin-alginate composite sponges as dermal substitutes for deep partial-thickness burns. Crosslinked keratin-alginate sponges were tested for the ability to support human dermal fibroblasts in vitro and to support the closure and healing of partial-thickness burn wounds in Sus scrofa pigs. Keratin-alginate composite sponges supported the enhanced proliferation of human dermal fibroblasts compared to alginate-only sponges and exhibited decreased contraction in vitro when compared to keratin only sponges. As dermal substitutes in vivo, the sponges supported the expression of keratin 14, alpha-smooth muscle actin, and collagen IV within wound sites, comparable to collagen sponges. Keratin-alginate composite sponges supported the regeneration of basement membranes in the wounds more than in collagen-treated wounds and non-grafted controls, suggesting the subsequent development of pathological scar tissues may be minimized. Results from this study indicate that crosslinked keratin-alginate sponges are suitable alternative dermal substitutes for clinical applications in wound healing and skin regeneration.


Assuntos
Alginatos/uso terapêutico , Queimaduras/terapia , Queratinas/uso terapêutico , Cicatrização , Alginatos/química , Alginatos/farmacologia , Animais , Curativos Hidrocoloides , Queimaduras/patologia , Queimaduras/fisiopatologia , Células Cultivadas , Derme/efeitos dos fármacos , Derme/patologia , Derme/fisiopatologia , Humanos , Hidrogéis/química , Hidrogéis/uso terapêutico , Queratinas/química , Queratinas/farmacologia , Masculino , Teste de Materiais , Índice de Gravidade de Doença , Pele/efeitos dos fármacos , Pele/patologia , Pele/fisiopatologia , Suínos , Cicatrização/efeitos dos fármacos , Cicatrização/fisiologia
16.
Int J Mol Sci ; 22(12)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208563

RESUMO

Bone exhibits piezoelectric properties. Thus, electrical stimulations such as pulsed electromagnetic fields (PEMFs) and stimuli-responsive piezoelectric properties of scaffolds have been investigated separately to evaluate their efficacy in supporting osteogenesis. However, current understanding of cells responding under the combined influence of PEMF and piezoelectric properties in scaffolds is still lacking. Therefore, in this study, we fabricated piezoelectric scaffolds by functionalization of polycaprolactone-tricalcium phosphate (PCL-TCP) films with a polyvinylidene fluoride (PVDF) coating that is self-polarized by a modified breath-figure technique. The osteoinductive properties of these PVDF-coated PCL-TCP films on MC3T3-E1 cells were studied under the stimulation of PEMF. Piezoelectric and ferroelectric characterization demonstrated that scaffolds with piezoelectric coefficient d33 = -1.2 pC/N were obtained at a powder dissolution temperature of 100 °C and coating relative humidity (RH) of 56%. DNA quantification showed that cell proliferation was significantly enhanced by PEMF as low as 0.6 mT and 50 Hz. Hydroxyapatite staining showed that cell mineralization was significantly enhanced by incorporation of PVDF coating. Gene expression study showed that the combination of PEMF and PVDF coating promoted late osteogenic gene expression marker most significantly. Collectively, our results suggest that the synergistic effects of PEMF and piezoelectric scaffolds on osteogenesis provide a promising alternative strategy for electrically augmented osteoinduction. The piezoelectric response of PVDF by PEMF, which could provide mechanical strain, is particularly interesting as it could deliver local mechanical stimulation to osteogenic cells using PEMF.


Assuntos
Fosfatos de Cálcio , Materiais Revestidos Biocompatíveis , Campos Eletromagnéticos , Osteogênese , Poliésteres , Polivinil , Alicerces Teciduais , Regeneração Óssea , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Materiais Revestidos Biocompatíveis/química , Expressão Gênica , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Osteogênese/efeitos da radiação , Poliésteres/química , Poliésteres/farmacologia , Polivinil/química , Solventes , Engenharia Tecidual , Difração de Raios X
17.
Technol Soc ; 66: 101676, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36540782

RESUMO

This study investigates the underlying motives for online fake news sharing during the COVID-19 pandemic, an unprecedented time that witnessed a spike in the spread of false content. Motives were identified based on a fake news sharing model developed using the SocioCultural-Psychological-Technology (SCulPT) model, Uses and Gratification (U&G) theory and Self-Determination Theory (SDT), and further extended using fake news predictors/gratifications from past studies. A self-administered survey resulted in 869 online Malaysian respondents aged between 18 and 59 years old (Mean = 22.6, Standard deviation = 6.13). Structured equation modelling revealed the fake news sharing model to collectively account for 49.2 % of the variance, with Altruism (ß = 0.333; p < 0.001), Ignorance (ß = 0.165; p < 0.001) and Entertainment (ß = 0.139; p < 0.001) significantly predicting the behaviour. Conversely, Availability/Effort, Pass Time and Fear of Missing Out were found to be insignificant. Our findings indicate that fake news sharing behavior is determined by different motives, hence these need to be understood in order to develop better solutions to mitigate this problem.

18.
Small ; 16(36): e2001246, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32495486

RESUMO

Ingestion of engineered nanomaterials (ENMs) is inevitable due to their widespread utilization in the agrifood industry. Safety evaluation has become pivotal to identify the consequences on human health of exposure to these ingested ENMs. Much of the current understanding of nanotoxicology in the gastrointestinal tract (GIT) is derived from studies utilizing pristine ENMs. In reality, agrifood ENMs interact with their microenvironment, and undergo multiple physicochemical transformations, such as aggregation/agglomeration, dissolution, speciation change, and surface characteristics alteration, across their life cycle from synthesis to consumption. This work sieves out the implications of ENM transformations on their behavior, stability, and reactivity in food and product matrices and through the GIT, in relation to measured toxicological profiles. In particular, a strong emphasis is given to understand the mechanisms through which these transformations can affect ENM induced gut nanotoxicity.


Assuntos
Trato Gastrointestinal , Nanoestruturas , Biotransformação , Meio Ambiente , Trato Gastrointestinal/efeitos dos fármacos , Humanos , Nanoestruturas/química , Nanoestruturas/toxicidade
19.
Small ; 16(34): e2003757, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32686344

RESUMO

Exogenous sources of amino acids are essential nutrients to fuel cancer growth. Here, the increased demand for amino acid displayed by cancer cells is unconventionally exploited as a design principle to replete cancer cells with apoptosis inducing nanoscopic porous amino acid mimics (Nano-PAAM). A small library consisting of nine essential amino acids nanoconjugates (30 nm) are synthesized, and the in vitro anticancer activity is evaluated. Among the Nano-PAAMs, l-phenylalanine functionalized Nano-PAAM (Nano-pPAAM) has emerged as a novel nanotherapeutics with excellent intrinsic anticancer and cancer-selective properties. The therapeutic efficacy of Nano-pPAAM against a panel of human breast, gastric, and skin cancer cells could be ascribed to the specific targeting of the overexpressed human large neutral amino acid transporter SLC7A5 (LAT-1) in cancer cells, and its intracellular reactive oxygen species (ROS) inducing properties of the nanoporous core. At the mechanistic level, it is revealed that Nano-pPAAM could activate both the extrinsic and intrinsic apoptosis pathways to exert a potent "double-whammy" anticancer effect. The potential clinical utility of Nano-pPAAM is further investigated using an MDA-MB-231 xenograft in NOD scid gamma mice, where an overall suppression of tumor growth by 60% is achieved without the aid of any drugs or application of external stimuli.


Assuntos
Antineoplásicos , Aminoácidos , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Linhagem Celular Tumoral , Camundongos , Nanoconjugados , Porosidade
20.
Small ; 16(21): e2000963, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32338442

RESUMO

Exposure to inhaled anthropogenic nanomaterials (NM) with dimension <100 nm has been implicated in numerous adverse respiratory outcomes. Although studies have identified key NM physiochemical determinants of pneumonic nanotoxicity, the complex interactive and cumulative effects of NM exposure, especially in individuals with preexisting inflammatory respiratory diseases, remain unclear. Herein, the susceptibility of primary human small airway epithelial cells (SAEC) exposed to a panel of reference NM, namely, CuO, ZnO, mild steel welding fume (MSWF), and nanofractions of copier center particles (Nano-CCP), is examined in normal and tumor necrosis factor alpha (TNF-α)-induced inflamed SAEC. Compared to normal SAEC, inflamed cells display an increased susceptibility to NM-induced cytotoxicity by 15-70% due to a higher basal level of intracellular reactive oxygen species (ROS). Among the NM screened, ZnO, CuO, and Nano-CCP are observed to trigger an overcompensatory response in normal SAEC, resulting in an increased tolerance against subsequent oxidative insults. However, the inflamed SAEC fails to adapt to the NM exposure due to an impaired nuclear factor erythroid 2-related factor 2 (Nrf2)-mediated cytoprotective response. The findings reveal that susceptibility to pulmonary nanotoxicity is highly dependent on the interplay between NM properties and inflammation of the alveolar milieu.


Assuntos
Células Epiteliais , Inflamação , Pulmão , Nanoestruturas , Exposição Ambiental , Células Epiteliais/efeitos dos fármacos , Humanos , Pulmão/efeitos dos fármacos , Nanoestruturas/toxicidade , Espécies Reativas de Oxigênio/metabolismo
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