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1.
Environ Sci Technol ; 56(20): 14605-14616, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36153963

RESUMO

We investigated the influence of biomass burning (BURN), Diwali fireworks, and fog events on the ambient fine particulate matter (PM2.5) oxidative potential (OP) during the postmonsoon (PMON) and winter season in Delhi, India. The real-time hourly averaged OP (based on a dithiothreitol assay) and PM2.5 chemical composition were measured intermittently from October 2019 to January 2020. The peak extrinsic OP (OPv: normalized by the volume of air) was observed during the winter fog (WFOG) (5.23 ± 4.6 nmol·min-1·m-3), whereas the intrinsic OP (OPm; normalized by the PM2.5 mass) was the highest during the Diwali firework-influenced period (29.4 ± 18.48 pmol·min-1·µg-1). Source apportionment analysis using positive matrix factorization revealed that traffic + resuspended dust-related emissions (39%) and secondary sulfate + oxidized organic aerosols (38%) were driving the OPv during the PMON period, whereas BURN aerosols dominated (37%) the OPv during the WFOG period. Firework-related emissions became a significant contributor (∼32%) to the OPv during the Diwali period (4 day period from October 26 to 29), and its contribution peaked (72%) on the night of Diwali. Discerning the influence of seasonal and episodic sources on health-relevant properties of PM2.5, such as OP, could help better understand the causal relationships between PM2.5 and health effects in India.


Assuntos
Poluentes Atmosféricos , Humanos , Aerossóis/análise , Poluentes Atmosféricos/análise , Biomassa , Ditiotreitol , Poeira/análise , Monitoramento Ambiental , Índia , Estresse Oxidativo , Material Particulado/análise , Estações do Ano , Sulfatos , Emissões de Veículos/análise
2.
Sci Adv ; 8(25): eabm6504, 2022 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-35749495

RESUMO

Aging has been reported to deteriorate the quantity and quality of mesenchymal stem cells (MSCs), which affect their therapeutic use in regenerative medicine. A dearth of age-related stem cell research further restricts their clinical applications. The present study explores the possibility of using MSCs derived from human gingival tissues (GMSCs) for studying their ex vivo growth characteristics and differentiation potential with respect to donor age. GMSCs displayed decreased in vitro adipogenesis and in vitro and in vivo osteogenesis with age, but in vitro neurogenesis remained unaffected. An increased expression of p53 and SIRT1 with donor age was correlated to their ability of eliminating tumorigenic events through apoptosis or autophagy, respectively. Irrespective of donor age, GMSCs displayed effective immunoregulation and regenerative potential in a mouse model of LPS-induced acute lung injury. Thus, we suggest the potential of GMSCs for designing cell-based immunomodulatory therapeutic approaches and their further extrapolation for acute inflammatory conditions such as acute respiratory distress syndrome and COVID-19.


Assuntos
COVID-19 , Células-Tronco Mesenquimais , Animais , Diferenciação Celular , Gengiva , Humanos , Células-Tronco Mesenquimais/metabolismo , Camundongos , Osteogênese
4.
Cardiol Young ; 31(8): 1213-1219, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34344494

RESUMO

Children with cardiac diseases suffer from significant morbidity and mortality secondary to thromboembolic complications. Anticoagulant agents currently used for thromboprophylaxis have many limitations, including subcutaneous administration (low molecular weight heparins) and requirement for frequent monitoring via venipuncture (vitamin K antagonists). Edoxaban is an oral direct factor Xa inhibitor without need of monitoring. In the treatment of venous thromboembolism in adults, edoxaban has shown to be effective and safe.This manuscript summarises the rationale and design of a phase 3, open-label, randomised controlled trial to evaluate and compare the safety and efficacy of edoxaban against standard of care (namely, vitamin K antagonist and low molecular weight heparin) in children with cardiac diseases.A goal of 150 children with cardiac diseases at risk of thromboembolic complications who need primary or secondary anticoagulant prophylaxis will be recruited. Eligible children between 6 months and <18 years of age will be randomised in a ratio of 2 to 1 for edoxaban versus standard of care. Randomisation will be stratified based on underlying cardiac disease and concomitant use of aspirin for patients other than Kawasaki disease. The primary outcome will be safety, comprised of major and clinically relevant non-major bleeding in first 3 months of treatment. Bleeding beyond 3 months, symptomatic and asymptomatic thromboembolic events, and pharmacokinetic and pharmacodynamic parameters will be evaluated as secondary outcomes.Randomised controlled anticoagulation trials are challenging in children. This study will evaluate a potentially valuable alternative of oral anticoagulant prophylactic use in children with cardiac diseases.


Assuntos
Cardiopatias , Tromboembolia Venosa , Adulto , Anticoagulantes/efeitos adversos , Criança , Cardiopatias/complicações , Humanos , Piridinas , Tiazóis , Tromboembolia Venosa/tratamento farmacológico , Tromboembolia Venosa/prevenção & controle
5.
Res Pract Thromb Haemost ; 4(5): 886-892, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32685899

RESUMO

BACKGROUND: Little evidence is available for treatment of pediatric venous thromboembolism (VTE). Large randomized controlled trials are challenging in children. Current antithrombotic agents have many limitations, including nonoral administration and frequent monitoring. Edoxaban is an oral direct inhibitor of factor Xa without need of monitoring. In adults with VTE, edoxaban has shown to be effective and safe. OBJECTIVES: The Edoxaban Hokusai VTE PEDIATRICS Study is an open-label, randomized clinical trial to evaluate pharmacokinetics (PK) and pharmacodynamics (PD) of edoxaban and whether edoxaban is noninferior to standard of care in treatment of pediatric VTE. METHODS: A goal of 274 patients will be recruited in 5 age categories. A multidose PK/PD assessment on day 5 in the first 12 patients of each age group is incorporated into this study. The primary composite efficacy outcome comprises symptomatic recurrent VTE, death due to VTE, and no change or extension of thrombotic burden. The principal safety end point is a combination of major and clinically relevant nonmajor bleeding. PK end points include apparent systemic clearance and volume of distribution of edoxaban. PD end points include prothrombin time, activated partial thromboplastin time, and anti-factor Xa level for the edoxaban treatment arm. RESULTS: To increase feasibility, the multidose PK/PD study is integrated in the phase 3 trial. In addition, thrombotic burden, which is a prognostic factor for post thrombotic syndrome in children, is one of the components of the primary composite efficacy outcome. CONCLUSION: This study will increase the level of evidence for treatment in pediatric VTE.

6.
Nanomedicine ; 15(1): 218-230, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30343014

RESUMO

Parathyroid hormone (PTH) has been a major contributor to the anabolic therapy for osteoporosis, but its delivery to bone without losing activity and avoiding adverse local effects remain a challenge. Being the natural component of bone, use of hydroxyapatite for this purpose brings a major breakthrough in synergistic anabolism. This study focuses on synthesis, characterization and evaluation of in vitro and in vivo efficacy of PTH (1-34) adsorbed hydroxyapatite nanocarrier for synergistic enhancement in the anabolic activity of PTH for bone regeneration. The negative zeta potential of this nanocarrier facilitated its affinity to the Ca2+ rich bone tissue and solubilization at low pH enhanced specific delivery of PTH to the resorption pits in osteoporotic bone. In this process, PTH retained its anabolic effect and at the same time an increase in bone mineral content indicated enhancement of the net formative effect of the PTH anabolic therapy.


Assuntos
Anabolizantes/administração & dosagem , Regeneração Óssea , Hormônios e Agentes Reguladores de Cálcio/administração & dosagem , Durapatita/química , Nanotubos/química , Osteoporose/tratamento farmacológico , Hormônio Paratireóideo/administração & dosagem , Animais , Apoptose , Proliferação de Células , Células Cultivadas , Feminino , Camundongos , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoporose/metabolismo , Ovariectomia
7.
Crit Rev Biomed Eng ; 46(5): 469-493, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30806263

RESUMO

Tissue engineering has gained attention in the past decade due to its efficient interaction with the host system and potential therapeutic capabilities. Although scaffold-based approaches provide much needed mechanical strength and support to the regenerating tissue, they also invite foreign body reaction initiated by macrophages, causing inflammation and toxicity, and may also sometime interfere with the regeneration of indigenous tissue due to very slow degradation. Therefore, spheroids provide a promising tool for improving cell survival and for preserving cell-to-cell interaction. They have promptly gained popularity because of their ability to provide superior cellular heterogeneity, nutrient and oxygen gradients (replicating the original tissue), matrix deposition, and gene expression profiles. Because of their ability to differentiate into multiple cell lineages, stem cell-based spheroids have opened new avenues for future regenerative medicine. In this review we focus on various methods for fabrication of spheroids from stem cells and their application in regenerative approaches for different tissues/organs.


Assuntos
Medicina Regenerativa/métodos , Esferoides Celulares/citologia , Esferoides Celulares/fisiologia , Células-Tronco/citologia , Células-Tronco/fisiologia , Engenharia Tecidual/métodos , Animais , Humanos , Transplante de Células-Tronco Mesenquimais/métodos , Transplante de Células-Tronco Mesenquimais/tendências , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Medicina Regenerativa/tendências , Esferoides Celulares/transplante , Alicerces Teciduais
8.
Crit Rev Biomed Eng ; 46(5): 429-468, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30806262

RESUMO

In recent years, mesenchymal stem cells (MSCs) derived from dental tissue have gained in popularity for tissue-engineering and regenerative medicine applications. The highly proliferative and self-renewing population of dental stem cells has the neural crest as their origin. This expands their applicability for regeneration of tissues from both ectochyme and mesenchymal origin. Ease of tissue harvest, high initial yield of cells, low population-doubling time, plasticity, multipotential capabilities, and immunomodulatory properties make them a suitable candidate for various therapeutic strategies. Furthermore, dental tissue-derived cells can be transformed into induced pluripotent stem cells to customize cell-based regenerative approaches. However, there is currently a lack of exhaustive comparative profiles of these dental tissues and their regenerative applications. We thereby present a comprehensive compilation of morphofunctional analyses and tissue-engineering applications of MSCs that are derived from tooth germ, exfoliated deciduous teeth, periodontal ligament, gingiva, dental pulp, alveolar bone, dental follicle, and apical papilla. Immunoregulatory properties of dental stem cells provide potential for both autologous and allogenic tissue-engineering approaches. In vitro and animal studies show promise for using dental stem cells in regenerative medicine. Eventually, the orchestration of clinical trials will require systematic monitoring of spontaneous in vitro transformations and complications associated with graft versus host response as well as a thorough understanding of underlying anabolic mechanisms.


Assuntos
Polpa Dentária/citologia , Células-Tronco Mesenquimais/fisiologia , Medicina Regenerativa , Engenharia Tecidual , Animais , Saco Dentário/citologia , Saco Dentário/fisiologia , Humanos , Transplante de Células-Tronco Mesenquimais/métodos , Transplante de Células-Tronco Mesenquimais/tendências , Células-Tronco Mesenquimais/citologia , Ligamento Periodontal/citologia , Ligamento Periodontal/fisiologia , Regeneração/fisiologia , Medicina Regenerativa/métodos , Medicina Regenerativa/tendências , Engenharia Tecidual/métodos , Engenharia Tecidual/tendências , Dente Decíduo/citologia , Dente Decíduo/fisiologia
9.
Stroke ; 45(8): 2372-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24947287

RESUMO

BACKGROUND AND PURPOSE: The once-daily oral factor Xa inhibitor, edoxaban, is as effective as warfarin in preventing stroke and systemic embolism while decreasing bleeding in a phase III trial of patients with atrial fibrillation at moderate-high stroke risk. Limited data regarding cerebrovascular events with edoxaban were reported previously. METHODS: We analyzed the subtypes of cerebrovascular events in 21 105 patients participating in Effective Anticoagulation with Factor Xa Next Generation in Atrial Fibrillation-Thrombolysis in Myocardial Infarction 48 (ENGAGE AF-TIMI 48) comparing outcomes among patients randomized to warfarin versus 2 edoxaban regimens (high dose, low dose). The primary end point for this prespecified analysis of cerebrovascular events was all stroke (ischemic plus hemorrhagic), defined as an abrupt onset of focal neurological deficit because of infarction or bleeding with symptoms lasting ≥24 hours or fatal in <24 hours. Independent stroke neurologists unaware of treatment adjudicated all cerebrovascular events. RESULTS: Patients randomized to high-dose edoxaban had fewer strokes on-treatment (hazard ratio, 0.80; 95% confidence interval, 0.65-0.98) than warfarin (median time-in-therapeutic range, 68.4%); patients in the low-dose edoxaban group had similar rates (hazard ratio, 1.10 versus warfarin; 95% confidence interval, 0.91-1.32). Rates of ischemic stroke or transient ischemic attack were similar with high-dose edoxaban (1.76% per year) and warfarin (1.73% per year; P=0.81), but more frequent with low-dose edoxaban (2.48% per year; P<0.001). Both edoxaban regimens significantly reduced hemorrhagic stroke and other subtypes of intracranial bleeds. CONCLUSIONS: In patients with atrial fibrillation, once-daily edoxaban was as effective as warfarin in preventing all strokes, with significant reductions in various subtypes of intracranial bleeding. Ischemic cerebrovascular event rates were similar with high-dose edoxaban and warfarin, whereas low-dose edoxaban was less effective than warfarin. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT00781391.


Assuntos
Anticoagulantes/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Piridinas/uso terapêutico , Acidente Vascular Cerebral/induzido quimicamente , Tiazóis/uso terapêutico , Varfarina/uso terapêutico , Idoso , Anticoagulantes/administração & dosagem , Anticoagulantes/efeitos adversos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Piridinas/administração & dosagem , Piridinas/efeitos adversos , Tiazóis/administração & dosagem , Tiazóis/efeitos adversos , Resultado do Tratamento , Varfarina/administração & dosagem , Varfarina/efeitos adversos
10.
BMJ Case Rep ; 20132013 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-23839612

RESUMO

A 14-year-old boy reported with a painless swelling over the right anterior mandible with missing right canine tooth. The lesion was diagnosed as 'central follicular adenomatoid odontogenic tumour' and excised surgically under general anaesthesia. The patient was on a year-long clinical and radiographical follow-up.


Assuntos
Ameloblastoma , Neoplasias Mandibulares , Adolescente , Ameloblastoma/diagnóstico , Ameloblastoma/cirurgia , Humanos , Masculino , Neoplasias Mandibulares/diagnóstico , Neoplasias Mandibulares/cirurgia
11.
Compr Ther ; 31(1): 72-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15793326

RESUMO

Clinical trials are an important part of medical research and must be done with good conduct and intention. Using a suitable approach is part of research practice, which favors protection of research subjects. Good Clinical Practice is being promulgated as a universal ethical approach toward protection of the human subject's rights. Appropriate scientific design, good performance, better analyses, informed consent, and credible scientific data with the confidentiality of the research subject all contribute to Good Clinical Practices. The first and possibly the most important step toward protection of the research subject is to appropriately obtain an informed consent, which identifies respect, beneficence, and justice for the enrolled research subjects.


Assuntos
Ensaios Clínicos como Assunto/ética , Ensaios Clínicos como Assunto/normas , Experimentação Humana/ética , Experimentação Humana/normas , Fidelidade a Diretrizes , Humanos , Consentimento Livre e Esclarecido/ética , Seleção de Pacientes
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