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1.
Laryngoscope Investig Otolaryngol ; 7(5): 1513-1520, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36258863

RESUMEN

Objectives/Hypothesis: Compare proteomic profiles of rabbit vocal folds (VFs) injected with micronized cross-linked jellyfish collagen "collagen Type 0" (MX-JC) against two clinical products for injection medialization laryngoplasty (IL). Study Design: Animal model. Methods: Left recurrent laryngeal nerve sectioning and IL were performed in New Zealand White rabbits (N = 6/group). Group 1 received (MX-JC) and adipose-derived stem cells (ADSCs), Group 2, MX-JC alone; Group 3, cross-linked hyaluronic acid; and Group 4, micronized acellular dermis. Animals were sacrificed at 4 and 12 weeks. Proteomic profiling of injected versus noninjected VFs by nano-liquid chromatography, tandem mass spectrometry, and reactome gene ontology analysis was performed. Results: Overall, 37-61 proteins were found to be upregulated and 60-284 downregulated in injected versus non-injected VFs (>1.5 fold, false discovery rate-adjusted p < .05). Over-representation analysis (% of total) revealed top up-regulated pathways at 4 and 12 weeks, respectively: Group 1, keratan sulfate metabolism (46%) and cellular processes (29%); Group 2, extracellular matrix (ECM)/collagen processes (33%) and beta oxidation (39%); Group 3, cellular processes (50%) and energy metabolism (100%); and Group 4, keratan sulfate metabolism (31%) and inflammation (50%). Top downregulated pathways were: Group 1, Inflammation (36%) and glucose/citric acid metabolism (42%); Group 2, cell signaling (38%) and glucose/citric acid metabolism (35%); Group 3, keratan sulfate metabolism (31%) and ECM/collagen processes (48%); and Group 4, glucose/citric acid metabolism (33%) and ECM/collagen processes (43%). Conclusions: MX-JC "collagen Type 0" upregulates pathways related to ECM/collagen formation and downregulates pathways related to inflammation suggesting that it is promising biomaterial for IL. Level of Evidence: NA.

2.
PLoS One ; 17(8): e0272552, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35976904

RESUMEN

There is an alarming shortage of qualified STEM teachers in American PK-12 schools. The COVID-19 pandemic may exacerbate this crisis and consequently affect who participates in future STEM innovation. At three points during the pandemic, we surveyed early career teachers who were supported by the National Science Foundation as they began teaching in high-needs school districts. Teachers who felt connected to their professional and academic communities reported intentions to remain in the profession, while those who felt isolated reported intentions of leaving. It is critical for STEM academics to maintain professional relationships with graduates who pursue STEM teaching professions after graduation.


Asunto(s)
COVID-19 , Personal Docente , COVID-19/epidemiología , Humanos , Intención , Pandemias , Instituciones Académicas , Estados Unidos
3.
Genes (Basel) ; 13(8)2022 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-35893052

RESUMEN

Mitochondria are a dynamic eukaryotic innovation that play diverse roles in biology and disease. The mitochondrial genome is remarkably conserved in all vertebrates, encoding the same 37-gene set and overall genomic structure, ranging from 16,596 base pairs (bp) in the teleost zebrafish (Danio rerio) to 16,569 bp in humans. Mitochondrial disorders are amongst the most prevalent inherited diseases, affecting roughly 1 in every 5000 individuals. Currently, few effective treatments exist for those with mitochondrial ailments, representing a major unmet patient need. Mitochondrial dysfunction is also a common component of a wide variety of other human illnesses, ranging from neurodegenerative disorders such as Huntington's disease and Parkinson's disease to autoimmune illnesses such as multiple sclerosis and rheumatoid arthritis. The electron transport chain (ETC) component of mitochondria is critical for mitochondrial biology and defects can lead to many mitochondrial disease symptoms. Here, we present a publicly available collection of genetic mutants created in highly conserved, nuclear-encoded mitochondrial genes in Danio rerio. The zebrafish system represents a potentially powerful new opportunity for the study of mitochondrial biology and disease due to the large number of orthologous genes shared with humans and the many advanced features of this model system, from genetics to imaging. This collection includes 15 mutant lines in 13 different genes created through locus-specific gene editing to induce frameshift or splice acceptor mutations, leading to predicted protein truncation during translation. Additionally, included are 11 lines created by the random insertion of the gene-breaking transposon (GBT) protein trap cassette. All these targeted mutant alleles truncate conserved domains of genes critical to the proper function of the ETC or genes that have been implicated in human mitochondrial disease. This collection is designed to accelerate the use of zebrafish to study many different aspects of mitochondrial function to widen our understanding of their role in biology and human disease.


Asunto(s)
Genoma Mitocondrial , Pez Cebra , Animales , Genes Mitocondriales , Humanos , Mitocondrias/genética , Mitocondrias/metabolismo , Pez Cebra/genética , Pez Cebra/metabolismo
4.
Laryngoscope Investig Otolaryngol ; 7(2): 454-459, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35434315

RESUMEN

Objectives: To examine the degree of agreement between MRI and histologically generated volumetric measurements of residual injection laryngoplasty material. Methods: Following left recurrent laryngeal nerve transection, rabbit vocal cords were injected with jellyfish collagen, Cymetra®, or Restylane®. Laryngeal tissue was harvested 4 or 12 weeks post injection followed by MRI imaging and histologic cross-sectioning. Two raters estimated the volume of remaining injection material in specimens within MRI and histologic axial cross sections. Wilcoxon signed rank tests were employed to detect gross differences between inter-rater measurements and between imaging modalities across time. Agreement between rater measurements and imaging (histology and MRI) was assessed using intra-class correlation coefficients. Results: Data was available from 16 rabbits sacrificed at 4 weeks (n = 8) and 12 weeks (n = 8). Inter-rater testing of MRI imaging revealed no significant differences (p > .05) between rater measurements across time points, and excellent agreement (0.93; 95% confidence interval 0.80-0.98) while histologically estimated volumes demonstrated a significant difference at 4 weeks (p < .05) and overall good agreement (0.89; 95% confidence interval 0.59-0.97). Comparison of MRI and histologically estimated volume measurements revealed significant differences at the 4-week time point (p < .05) but not at 12 weeks (p > .05). Overall, there is only moderate agreement between MRI and histology estimates (0.72; 95% confidence interval 0.22-0.90). Conclusions: MRI imaging demonstrates good reliability and similar estimates of volume to histologically estimated measurements of residual injection laryngoplasty material at time points clinically relevant for future injection laryngoplasty experiments. Level of Evidence: NA.

5.
Arch Public Health ; 79(1): 181, 2021 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-34670629

RESUMEN

BACKGROUND: Implementation of quality improvement (QI) practices varies considerably among public health units (PHUs) in Ontario. With the emphasis on continuous quality improvement (CQI) in the revised Ontario Public Health Standards (OPHS), there is a need to understand the level of QI maturity in Ontario's PHUs. The objective of this research was to establish a baseline understanding of QI maturity in Ontario's PHUs. METHODS: The QI Maturity Tool - Modified Ontario Version was used to assess the state of QI maturity in 34 PHUs across Ontario. QI maturity was assessed through 23 questions across three dimensions: QI Organizational Culture; QI Capacity and Competency; and QI Perceived Value. QI maturity scores were classified into five stages: Beginning; Emerging; Progressing; Achieving; and Excelling. QI maturity scores were calculated for each of the 34 participating PHUs to determine their stage of QI maturity. Each PHU's score was then used to determine the provincial average for QI maturity. Participants were also asked to answer three questions related to core CQI organizational structures. RESULTS: Across the 34 PHUs, 3503 staff participated in the survey. A review of individual PHU scores indicates that Ontario's PHUs are at varying stages of QI maturity. The average QI maturity score of 4.94 for the 34 participating PHUs places the provincial average in the "Emerging" stage of QI maturity. By QI dimensions, the participating PHUs scored in the "Emerging" stage for QI Organizational Culture (5.09), the "Beginning" stage for QI Competency and Capacity (4.58), and the "Achieving" stage for QI Perceived Value (6.00). CONCLUSION: There is an urgent need for Ontario's PHUs to progress to higher stages of QI maturity. Participants place a high value on QI, but collectively are at less "mature" stages of QI in relation to QI organizational culture and the competency and capacity to engage in QI activities. PHUs should leverage the value that staff place on QI to foster the development of a culture of QI and provide staff with relevant knowledge and skills to engage in QI activities.

6.
Laryngoscope ; 131(8): E2452-E2460, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33847388

RESUMEN

OBJECTIVES/HYPOTHESIS: Test a new jellyfish collagen biomaterial aimed to increase duration of injection medialization laryngoplasty (IL) against two products in clinical practice. STUDY DESIGN: Animal model. METHODS: Left recurrent laryngeal nerve sectioning and IL were performed in New Zealand White rabbits (N = 6/group). Group 1 received micronized cross-linked jellyfish collagen (MX-JC) and adipose derived stem cells (ADSCs), Group 2, MX-JC alone, Group 3, cross-linked hyaluronic acid (X-HA), and Group 4, micronized acellular dermis (MACD). Animals were sacrificed at 4 and 12 weeks. Major outcomes were MRI tissue volumes and histopathology. RESULTS: After 100 µL IL MRI volumes (means ± STD) at 4 and 12 weeks were: Group 1: 27.2 ± 15.6 and 13.1 ± 5.2 µL, Group 2: 60.8 ± 18 and 27.8 ± 2.47 µL, Group 3: 27.4 ± 12 and 10.6 ± 8 µL, and Group 4: 37.5 ± 11 and 9.85 ± 1 µL. Group 2 volumes were largest and Group 3 were smallest in all comparisons (P < .05). Histologically, low grade inflammatory responses were observed in Group 1, mild histiocytic infiltration in Group 2, widespread muscle fiber loss in Group 3, and plasmocytic infiltration in Group 4. CONCLUSIONS: MX-JC showed the least resorption at 4 and 12 weeks among all groups. T cell inflammatory responses were observed with MX-JC but were reduced by 12 weeks while B cell immune responses, indicative of antibody priming, were predominantly noted with MACD. MX-JC + ADSC showed low grade immunity while the XHA showed greater myocyte loss compared to the other groups. LEVEL OF EVIDENCE: NA Laryngoscope, 131:E2452-E2460, 2021.


Asunto(s)
Colágeno/farmacología , Ácido Hialurónico/análogos & derivados , Laringoplastia/métodos , Imagen por Resonancia Magnética/métodos , Parálisis de los Pliegues Vocales/terapia , Dermis Acelular/efectos adversos , Animales , Linfocitos B/inmunología , Materiales Biocompatibles/administración & dosificación , Materiales Biocompatibles/farmacología , Cadáver , Colágeno/administración & dosificación , Modelos Animales de Enfermedad , Femenino , Ácido Hialurónico/administración & dosificación , Ácido Hialurónico/farmacología , Inmunidad/inmunología , Inflamación/patología , Imagen por Resonancia Magnética/estadística & datos numéricos , Células Madre Mesenquimatosas/patología , Células Plasmáticas/inmunología , Pautas de la Práctica en Medicina , Conejos , Traumatismos del Nervio Laríngeo Recurrente/complicaciones , Traumatismos del Nervio Laríngeo Recurrente/patología , Linfocitos T/patología , Parálisis de los Pliegues Vocales/diagnóstico , Parálisis de los Pliegues Vocales/etiología
7.
Tissue Eng Part A ; 27(3-4): 237-245, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32640938

RESUMEN

Craniofacial reconstruction of critical bone defects typically requires a bone graft. As graft availability may be restricted by disease or comorbidities, tissue engineering approaches are actively sought. The pericranium could provide new bone graft material. During development and repair, bone transitions through a chondrogenic phase. However, with tissue engineering, pluripotent cells can differentiate directly into bone cells. Does ability to recapitulate bone formation in vitro affect osteogenesis and vascularization of pericranium grafts? To answer this, we obtained tissue from nine patients with preplanned craniotomy surgery and studied three-dimensional osteogenesis and angiogenesis of pericranium-derived spheroids. First, we established growth and differentiation conditions on Matrigel. For each spheroid sample, we investigated (i) continuous osteogenic differentiation (COD) and (ii) osteogenic differentiation preceded by chondrogenesis (CD → OD). The effect of vascular endothelial growth factor (VEGF) was compared to VEGF supplemented with fibroblast growth factor, interleukin (IL)-1, IL-6, platelet-derived growth factor, and tumor necrosis factor-α, a growth factor mix (GFM) with possible synergistic effects. In this limited sample, we observed no age- or sex-related differences in cell expansion. Similarly, no statistically significant differences in osteogenic or angiogenic scores between COD or CD → OD spheroids were noted with regular media. In COD, however, VEGF statistically significantly increased angiogenesis compared to control media (p = 0.007). Also, in COD, both VEGF and VEGF + GFM increased osteogenesis (p = 0.047 and p = 0.038, respectively). By contrast, in CD → OD, neither VEGF nor VEGF + GFM yielded statistically significant angiogenesis or osteogenesis scores compared to control media. To understand these results, we characterized spheroid protein expression by nanoliquid chromatography coupled to tandem mass spectrometry. Nine angiogenic proteins were either uniquely expressed or upregulated in COD compared to CD → OD: (i) endothelial markers JUP, PTGIS, PTGS2, and TYMP, (ii) tissue remodeling factors CHI3L1 and MMP14, and (iii) metabolic pathways modulators ANGPTL4, ITGA5, and WNT5A. ANGPTL4, ITGA5, PTGIS, PTGS2, and WNT5A define a conserved angiogenic network and were >2-fold increased in VEGF compared to VEGF + GFM. Finally, we examined bone formation on printable poly-(propylene-fumarate) (PPF) scaffolds for individualized grafting. Under COD + VEGF conditions, PPF scaffolds loaded with pericranium-derived cells displayed hallmarks of spongiform-like bone formation. Thus, the human pericranium may be a potential repository for bone-generating cells with applications in craniofacial bone repair using tissue printing.


Asunto(s)
Osteogénesis , Factor A de Crecimiento Endotelial Vascular , Diferenciación Celular , Condrogénesis , Humanos , Neovascularización Fisiológica , Factores de Crecimiento Endotelial Vascular
8.
J Forensic Sci ; 65(1): 248-254, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31365128

RESUMEN

This study presents a number of pseudo-operational trials on plastic bags investigating the double- and co-fuming process of a one-step fluorescent cyanoacrylate (LumicyanoTM ) in comparisons with the two-step process with basic yellow 40 (BY40) staining for the detection of latent fingermarks. The results demonstrate that both Lumicyano solution and dye contribute to the increased detection of latent fingermarks during the double-fuming process (trial 1). Co-fuming the Lumicyano solution and dye separately (at a concentration of 8%) but simultaneously was less effective than 8% Lumicyano (trial 2). Co-fuming Lumicyano 8% and an additional 8% Lumicyano dye by weight was more effective than Lumicyano 8% (trial 3), possibly due to increased fluorescent material deposition during co-fuming allowing for better visualization. The use of BY40 after Lumicyano resulted in a considerable increase in detected fingermarks.

9.
Acta Neurochir Suppl ; 126: 269-273, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29492573

RESUMEN

OBJECTIVE: To determine normal ranges for traditional transcranial Doppler (TCD) measurements for two age groups (14-19 and 20-29 years) and compare to existing literature results. The development of a normal range for TCD measurements will be required for the development of diagnostic and prognostic tests in the future. MATERIALS AND METHODS: We performed TCD on the middle cerebral artery on 147 healthy subjects aged 18.9 years (SD = 2.1) and calculated mean cerebral blood flow velocity (mCBFV) and pulsatility index (PI). The study population was divided into two age populations (14-19 and 20-29 years). RESULTS: There was a significant decrease in PI (p = 0.015) for the older age group with no difference in mCBFV. CONCLUSION: Age-related, normal data are a prerequisite for TCD to continue to gain clinical acceptance. Our correlation of age-related TCD findings with previously published results as the generally accepted "gold standard" underlines the validity and sensitivity of this ultrasound method.


Asunto(s)
Circulación Cerebrovascular/fisiología , Arteria Cerebral Media/diagnóstico por imagen , Flujo Pulsátil/fisiología , Adolescente , Adulto , Factores de Edad , Velocidad del Flujo Sanguíneo/fisiología , Femenino , Voluntarios Sanos , Humanos , Masculino , Arteria Cerebral Media/fisiología , Valores de Referencia , Ultrasonografía Doppler Transcraneal , Adulto Joven
10.
Phytochemistry ; 75: 32-40, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22217745

RESUMEN

Potato (Solanum tuberosum L.), a domesticated species that is the fourth most important world agricultural commodity, requires significant management to minimize the effects of herbivore and pathogen damage on crop yield. A wild relative, Solanum chacoense Bitt., has been of interest to plant breeders because it produces an abundance of novel steroidal glycoalkaloid compounds, leptines and leptinines, which are particularly effective deterrents of herbivory by the Colorado potato beetle (Leptinotarsa decemlineata Say). Biochemical approaches were used in this study to investigate the formation and accumulation of SGAs in S. chacoense. SGA contents were determined in various organs at different stages of organ maturity during a time course of plant development. Leptines and leptinines were the main contributors to the increased levels in SGA concentration measured in the aerial versus the subterranean organs of S. chacoense accession 8380-1. Leptines were not detected in aboveground stolons until the stage where shoots had formed mature chlorophyllous leaves. To gain insights into SGA biosynthesis, the abundance of SGAs and steady-state transcripts of genes coding for enzymes of the central terpene and SGA-specific pathways in various plant organs at anthesis were compared. For two genes of primary terpene metabolism, transcript and SGA abundances were correlated, although with some discrepancies. For genes associated with SGA biosynthesis, transcripts were not detected in some tissues containing SGAs; however these transcripts were detected in the progenitor tissues, indicating the possibility that under our standard growth conditions, SGA biosynthesis is largely limited to highly proliferative tissues such as shoot, root and floral meristems.


Asunto(s)
Alcaloides Solanáceos/metabolismo , Solanum tuberosum/metabolismo , Conformación Molecular , Extractos Vegetales/análisis , Extractos Vegetales/metabolismo , Raíces de Plantas/química , Raíces de Plantas/metabolismo , Alcaloides Solanáceos/análisis , Solanum tuberosum/química , Solanum tuberosum/crecimiento & desarrollo , Estereoisomerismo
11.
Healthc Policy ; 1(4): 106-23, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-19305685

RESUMEN

This paper addresses the question: Did the implementation of managed competition in Ontario increase turnover in home care agencies? This question is addressed through a case study analysis of the impacts of tendering on the exiting home care labour force from three non-profit home care agencies during the period 1997 to 2001 in a mid-sized city in Ontario. These agencies provided 85% of the market share in 1996. Findings showed that 52% of the nurses and personal support workers (PSWs) left their agency over the five-year period. Analysis of the turnover data showed a temporal association between the implementation of managed competition and turnover. Additional support for the argument that the implementation of managed competition increased turnover is provided through analysis of a questionnaire sent to nurses and personal support workers who had left their agency during this period. Respondents indicated dissatisfaction with their pay, hours of work, benefits, heavy workload and lack of support from their supervisors/managers (all factors affected by the marketization of the home care sector) as reasons for leaving. Of those employed, only one-quarter remained in home care; most of those remaining were working in other healthcare fields such as hospitals and long-term care institutions. However, about one-third of employed PSWs were no longer working in the healthcare field.

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