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1.
Knee Surg Sports Traumatol Arthrosc ; 28(12): 3827-3842, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32006075

RESUMO

PURPOSE: This review aimed to evaluate the efficacy of intra-articular injections of bone marrow derived mesenchymal stem cells (BM-MSCs) for the treatment of knee osteoarthritis (KOA). METHODS: This narrative review evaluates recent English language clinical data and published research articles between 2014 and 2019. Key word search strings of ((("bone marrow-derived mesenchymal stem cell" OR "bone marrow mesenchymal stromal cell" OR "bone marrow stromal cell")) AND ("osteoarthritis" OR "knee osteoarthritis")) AND ("human" OR "clinical"))) AND "intra-articular injection" were used to identify relevant articles using PMC, Cochrane Library, Web Of Science and Scopus databases. RESULTS: Pre-clinical studies have demonstrated successful, safe and encouraging results for articular cartilage repair and regeneration. This is concluded to be due to the multilineage differential potential, immunosuppressive and self-renewal capabilities of BM-MSCs, which have shown to augment pain and improve functional outcomes. Subsequently, clinical applications of intra-articular injections of BM-MSCs are steadily increasing, with most studies demonstrating a decrease in poor cartilage index, improvements in pain, function and Quality of Life (QoL); with moderate-to-high level evidence regarding safety for therapeutic administration. However, low confidence in clinical efficacy remains due to a plethora of heterogenous methodologies utilised, resulting in challenging study comparisons. A moderate number of cells (40 × 106) were identified as most likely to achieve optimal responses in individuals with grade ≥ 2 KOA. Likewise, significant improvements were reported when using lower (24 × 106) and higher (100 × 106) cell numbers, although adverse effects including persistent pain and swelling were a consequence. CONCLUSION: Overall, the benefits of intra-articular injections of BM-MSCs were deemed to outweigh the adverse effects; thus, this treatment be considered as a future therapy strategy. To realise this, long-term large-scale randomised clinical trials are required to enable improved interpretations, to determine the validity of efficacy in future studies. LEVEL OF EVIDENCE: IV.


Assuntos
Cartilagem Articular/fisiologia , Transplante de Células-Tronco Mesenquimais , Osteoartrite do Joelho/terapia , Regeneração , Células da Medula Óssea , Humanos , Injeções Intra-Articulares , Células-Tronco Mesenquimais , Qualidade de Vida , Resultado do Tratamento
2.
Int J Nurs Educ Scholarsh ; 16(1)2019 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-30862758

RESUMO

The licensing exam for registered nurses in Canada has recently been changed from a Canadian developed, owned and delivered exam to the National Council Licensure Examination for Registered Nurses (NCLEX-RN) which originates from the United States. Rationale for this exam change focused on transitioning to a computer-based exam that has increased writing dates, with increased security, validated psychometrics, increased exam result delivery, and an anticipated decrease in expense to students. Concerns have arisen around the acceptance, implementation and delivery of this exam to Canadian nursing students that reflects the broad Canadian landscape of education and nursing practice. The experience of a Canadian nurse educator in working to facilitate students' transition to this exam is addressed using an institutional ethnographic lens. Finally, we come to conclusions about the importance of countries utilizing licensing exams that reflect their nursing education and practice.


Assuntos
Competência Clínica/normas , Avaliação Educacional/normas , Licenciamento em Enfermagem/normas , Licenciamento/normas , Canadá , Currículo/normas , Docentes de Enfermagem/normas , Humanos , Pesquisa em Educação em Enfermagem , Avaliação de Resultados em Cuidados de Saúde , Pesquisa Qualitativa , Estudantes de Enfermagem , Estados Unidos
3.
Philos Trans A Math Phys Eng Sci ; 376(2115)2018 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-29431682

RESUMO

We present putative global minima for the micro-hydrated sulfite SO32-(H2O) N and chlorate ClO3-(H2O) N systems in the range 3≤N≤15 found using basin-hopping global structure optimization with an empirical potential. We present a structural analysis of the hydration of a large number of minimized structures for hydrated sulfite and chlorate clusters in the range 3≤N≤50. We show that sulfite is a significantly stronger net acceptor of hydrogen bonding within water clusters than chlorate, completely suppressing the appearance of hydroxyl groups pointing out from the cluster surface (dangling OH bonds), in low-energy clusters. We also present a qualitative analysis of a highly explored energy landscape in the region of the global minimum of the eight water hydrated sulfite and chlorate systems.This article is part of the theme issue 'Modern theoretical chemistry'.

4.
Chem Mater ; 36(10): 5063-5076, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38828186

RESUMO

Solid-state polymer electrolytes can enable the safe operation of high energy density lithium metal batteries; unfortunately, they have low ionic conductivity and poor redox stability at electrode interfaces. Fluorinated ether polymer electrolytes are a promising approach because the ether units can solvate and conduct ions, while the fluorinated moieties can increase oxidative stability. However, current perfluoropolyether (PFPE) electrolytes exhibit deficient lithium-ion coordination and ion transport. Here, we incorporate cross-linked poly(ethylene glycol) (PEG) units within the PFPE matrix and increase the polymer blend electrolyte conductivity by 6 orders of magnitude as compared to pure PFPE at 60 °C from 1.55 × 10-11 to 2.26 × 10-5 S/cm. Blending varying ratios of PEG and PFPE induces microscale phase separation, and we show the impact of morphology on ion solvation and dynamics in the electrolyte. Spectroscopy and simulations show weak ion-PFPE interactions, which promote salt phase segregation into-and ion transport within-the PEG domain. These polymer electrolytes show promise for use in high-voltage lithium metal batteries with improved Li|Li cycling due to enhanced mechanical properties and high-voltage stability beyond 6 V versus Li/Li+. Our work provides insights into transport and stability in fluorinated polymer electrolytes for next-generation batteries.

5.
Blood ; 118(15): 4265-73, 2011 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-21803846

RESUMO

The activation of endothelial cells is critical to initiating an inflammatory response. Activation induces the fusion of Weibel-Palade Bodies (WPB) with the plasma membrane, thus transferring P-selectin and VWF to the cell surface, where they act in the recruitment of leukocytes and platelets, respectively. CD63 has long been an established component of WPB, but the functional significance of its presence within an organelle that acts in inflammation and hemostasis was unknown. We find that ablating CD63 expression leads to a loss of P-selectin-dependent function: CD63-deficient HUVECs fail to recruit leukocytes, CD63-deficient mice exhibit a significant reduction in both leukocyte rolling and recruitment and we show a failure of leukocyte extravasation in a peritonitis model. Loss of CD63 has a similar phenotype to loss of P-selectin itself, thus CD63 is an essential cofactor to P-selectin.


Assuntos
Células Endoteliais/metabolismo , Migração e Rolagem de Leucócitos , Leucócitos/metabolismo , Selectina-P/metabolismo , Tetraspanina 30/metabolismo , Animais , Linhagem Celular , Membrana Celular/genética , Membrana Celular/metabolismo , Membrana Celular/patologia , Células Endoteliais/patologia , Técnicas de Silenciamento de Genes , Leucócitos/patologia , Camundongos , Camundongos Knockout , Selectina-P/genética , Peritonite/genética , Peritonite/metabolismo , Peritonite/patologia , Tetraspanina 30/genética , Corpos de Weibel-Palade/genética , Corpos de Weibel-Palade/metabolismo
6.
Environ Toxicol Chem ; 42(6): 1199-1211, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36942360

RESUMO

Commercially available headspace solid-phase microextraction (HS-SPME) fibers have been used for years to extract pesticides and polychlorinated biphenyls from aqueous samples at the expected ultratrace levels (picograms per liter or parts per quadrillion) in alpine lakes. Several variables of the HS-SPME technique have been adequately evaluated, including water temperature, pH, salt content, fiber type and coating thickness, length of fiber-sample exposure, and liquid immersion versus headspace exposure; but surprisingly, analyte recovery as a function of analyte concentration and storage time has not been included in previous studies, which can be important for remote sampling sites. Seven hydrophobic chlorinated pollutants were identified in alpine lake water (out of 54 analyzed); but recovery using the common SPME technique was found to be inconsistent as the analyte concentration decreases, and the recovery trend as a function of concentration varies on a compound-to-compound basis that could result in a large underestimation of analyte concentrations in field samples. Of the 54 compounds surveyed, o,p'-dichlorodiphenyltrichloroethane (DDT), p,p'-DDT, p,p'-dichlorodiphenyldichloroethylene (DDE), o,p'-DDE, chlorthal-dimethyl, endosulfan I, γ-hexachlorocyclohexane, heptachlor, and trans-nonachlor were generally measured at concentrations between 1 and 150 pg/L (parts per quadrillion). No study to date has evaluated this commonly used but unstandardized technique for analyte recovery as a function of analyte concentration or storage time of aqueous samples. Environ Toxicol Chem 2023;42:1199-1211. © 2023 SETAC.


Assuntos
Poluentes Ambientais , Hidrocarbonetos Clorados , Praguicidas , DDT/análise , Poluentes Ambientais/análise , Lagos , Microextração em Fase Sólida , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Diclorodifenil Dicloroetileno/análise , Água
7.
J Insect Physiol ; 54(3): 563-72, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18241882

RESUMO

Proteolytic activities in soluble protein extracts from Mamestra brassicae (cabbage moth) larval midgut were analysed using specific peptide substrates and proteinase inhibitors. Serine proteinases were the major activities detected, with chymotrypsin-like and trypsin-like activities being responsible for approximately 62% and 19% of the total proteolytic activity towards a non-specific protein substrate. Only small amounts of elastase-like activities could be detected. The serine proteinases were active across the pH range 7-12.5, with both trypsin-like and chymotrypsin-like activities maximal at pH 11.5. The digestive proteinases were stable to the alkaline environment of the lepidopteran gut over the timescale of passage of food through the gut, with 50% of trypsin and 40% of chymotrypsin activity remaining after 6h at pH 12, 37 degrees C. Soybean Kunitz trypsin inhibitor (SKTI) ingestion by the larvae had a growth-inhibitory effect, and induced inhibitor-insensitive trypsin-like activity. Qualitative and quantitative changes in proteinase activity bands after gel electrophoresis of gut extracts were evident in SKTI-fed larvae when compared with controls, with increases in levels of most bands, appearance of new bands, and a decrease in the major proteinase band present in extracts from control insects.


Assuntos
Mariposas/enzimologia , Serina Endopeptidases/metabolismo , Inibidor da Tripsina de Soja de Kunitz/farmacologia , Animais , Trato Gastrointestinal/enzimologia , Larva/efeitos dos fármacos , Larva/enzimologia , Larva/crescimento & desenvolvimento , Mariposas/efeitos dos fármacos , Mariposas/crescimento & desenvolvimento
8.
ACS Chem Biol ; 12(9): 2335-2344, 2017 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-28723094

RESUMO

Base excision repair glycosylases locate and remove damaged bases in DNA with remarkable specificity. The MutY glycosylases, unusual for their excision of undamaged adenines mispaired to the oxidized base 8-oxoguanine (OG), must recognize both bases of the mispair in order to prevent promutagenic activity. Moreover, MutY must effectively find OG:A mismatches within the context of highly abundant and structurally similar T:A base pairs. Very little is known about the factors that initiate MutY's interaction with the substrate when it first encounters an intrahelical OG:A mispair, or about the order of recognition checkpoints. Here, we used structure-activity relationships (SAR) to investigate the features that influence the in vitro measured parameters of mismatch affinity and adenine base excision efficiency by E. coli MutY. We also evaluated the impacts of the same substrate alterations on MutY-mediated repair in a cellular context. Our results show that MutY relies strongly on the presence of the OG base and recognizes multiple structural features at different stages of recognition and catalysis to ensure that only inappropriately mispaired adenines are excised. Notably, some OG modifications resulted in more dramatic reductions in cellular repair than in the in vitro kinetic parameters, indicating their importance for initial recognition events needed to locate the mismatch within DNA. Indeed, the initial encounter of MutY with its target base pair may rely on specific interactions with the 2-amino group of OG in the major groove, a feature that distinguishes OG:A from T:A base pairs. These results furthermore suggest that inefficient substrate location in human MutY homologue variants may prove predictive for the early onset colorectal cancer phenotype known as MUTYH-Associated Polyposis, or MAP.


Assuntos
Adenina/metabolismo , Pareamento Incorreto de Bases , DNA Glicosilases/metabolismo , Reparo do DNA , Escherichia coli/enzimologia , Guanina/análogos & derivados , Adenina/análise , Escherichia coli/química , Escherichia coli/genética , Escherichia coli/metabolismo , Guanina/análise , Guanina/metabolismo , Modelos Moleculares , Especificidade por Substrato
9.
J Marital Fam Ther ; 42(1): 168-84, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25626719

RESUMO

For over 20 years, family therapist Karl Tomm has been engaging families and couples with a therapeutic intervention he calls Internalized Other Interviewing (IOI). The IOI (cf. Emmerson-Whyte, 2010; Hurley, 2006) entails interviewing clients, from the personal experiences of partners and family members as an internalized other. The IOI is based on the idea that through dialogues over time, one can internalize a sense of one's conversational partner responsiveness in reliably anticipated ways. Anyone who has thought in a conversation with a family member or partner, "Oh there s/he goes again," or anticipates next words before they leave the other's mouth, has a sense of what we are calling an internalized other. For Tomm, the internalized anticipations partners and family members may have offers entry points into new dialogues with therapeutic potential-particularly, when their actual dialogues get stuck in dispreferred patterns.


Assuntos
Relações Familiares/psicologia , Terapia Familiar/métodos , Teoria da Mente , Adolescente , Adulto , Feminino , Humanos , Entrevista Psicológica , Narração , Pesquisa Qualitativa
10.
Arch Pediatr Adolesc Med ; 165(4): 346-53, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21135318

RESUMO

OBJECTIVES: To investigate participation patterns in the National School Lunch Program (NSLP) among low-income children from kindergarten to fifth grade and to examine the ways in which participation influences sex differences in the trajectories of body mass index (BMI) through the eighth grade. DESIGN: Longitudinal, secondary data analysis. SETTING: Sample of low-income US children who entered kindergarten in 1998. PARTICIPANTS: Girls (n = 574) and boys (n = 566) from low-income families who participated in the Early Childhood Longitudinal Study, Kindergarten Cohort. MAIN EXPOSURE: Participation in the NSLP. MAIN OUTCOME MEASURES: Temporary and persistent patterns of NSLP participation, and age-specific and sex-specific BMI raw scores calculated at 5 data points. RESULTS: Among the low-income children who attended schools that participated in the NSLP, both the children who persistently participated in the program and those who temporarily participated in the program displayed similar socioeconomically disadvantaged factors. Nonlinear mixed models indicated a larger rate of change in BMI (ie, an increase) among low-income, participating girls than among low-income, nonparticipating girls; however, mean BMIs did not significantly differ between low-income girls who participated and those who did not participate. No significant differences were observed among low-income boys. CONCLUSIONS: Results suggest that participation in the NSLP is associated with rapid weight gain for low-income girls but not for low-income boys.


Assuntos
Índice de Massa Corporal , Desenvolvimento Infantil/fisiologia , Serviços de Alimentação/estatística & dados numéricos , Renda , Pobreza , Instituições Acadêmicas , Fatores Sexuais , Criança , Estudos de Coortes , Dieta , Feminino , Humanos , Masculino , Estudos Retrospectivos , Estados Unidos
11.
J Cell Biol ; 194(4): 613-29, 2011 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-21844207

RESUMO

The study of actin in regulated exocytosis has a long history with many different results in numerous systems. A major limitation on identifying precise mechanisms has been the paucity of experimental systems in which actin function has been directly assessed alongside granule content release at distinct steps of exocytosis of a single secretory organelle with sufficient spatiotemporal resolution. Using dual-color confocal microscopy and correlative electron microscopy in human endothelial cells, we visually distinguished two sequential steps of secretagogue-stimulated exocytosis: fusion of individual secretory granules (Weibel-Palade bodies [WPBs]) and subsequent expulsion of von Willebrand factor (VWF) content. Based on our observations, we conclude that for fusion, WPBs are released from cellular sites of actin anchorage. However, once fused, a dynamic ring of actin filaments and myosin II forms around the granule, and actomyosin II contractility squeezes VWF content out into the extracellular environment. This study therefore demonstrates how discrete actin cytoskeleton functions within a single cellular system explain actin filament-based prevention and promotion of specific exocytic steps during regulated secretion.


Assuntos
Actomiosina/metabolismo , Células Endoteliais/metabolismo , Exocitose , Corpos de Weibel-Palade/metabolismo , Fator de von Willebrand/metabolismo , Citoesqueleto de Actina/metabolismo , Células Cultivadas , Citocalasinas/farmacologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/ultraestrutura , Exocitose/efeitos dos fármacos , Humanos , Fusão de Membrana , Microscopia Confocal , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Microscopia de Vídeo , Miosina Tipo II/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Fatores de Tempo , Transfecção , Corpos de Weibel-Palade/efeitos dos fármacos , Corpos de Weibel-Palade/ultraestrutura
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