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1.
Heather B Hunt Nicholas A Miller Kimberly J Hemmerling Maho Koga Kelsie A Lopez Erik A Taylor Deborah E Sellmeyer Kendall F Moseley Eve Donnelly 《Journal of bone and mineral research》2021,36(2):334-346
The risk of fragility fracture increases for people with type 2 diabetes mellitus (T2DM), even after controlling for bone mineral density, body mass index, visual impairment, and falls. We hypothesize that progressive glycemic derangement alters microscale bone tissue composition. We used Fourier-transform infrared (FTIR) imaging to analyze the composition of iliac crest biopsies from cohorts of postmenopausal women characterized by oral glucose tolerance testing: normal glucose tolerance (NGT; n = 35, age = 65 ± 7 years, HbA1c = 5.8 ± 0.3%), impaired glucose tolerance (IGT; n = 26, age = 64 ± 5 years, HbA1c = 6.0 ± 0.4%), and overt T2DM on insulin (n = 25, age = 64 ± 6 years, HbA1c = 9.13 ± 0.6). The distributions of cortical bone mineral content had greater mean values (+7%) and were narrower (−10%) in T2DM versus NGT groups (p < 0.05). The distributions of acid phosphate, an indicator of new mineral, were narrower in cortical T2DM versus NGT and IGT groups (−14% and −14%, respectively) and in trabecular NGT and IGT versus T2DM groups (−11% and −10%, respectively) (all p < 0.05). The distributions of crystallinity were wider in cortical NGT versus T2DM groups (+16%) and in trabecular NGT versus T2DM groups (+14%) (all p < 0.05). Additionally, bone turnover was lower in T2DM versus NGT groups (P1NP: −25%, CTx: −30%, ucOC: −24%). Serum pentosidine was similar across groups. The FTIR compositional and biochemical marker values of the IGT group typically fell between the NGT and T2DM group values, although the differences were not always statistically significant. In summary, worsening glycemic control was associated with greater mineral content and narrower distributions of acid phosphate, an indicator of new mineral, which together are consistent with observations of lower turnover; however, wider distributions of mineral crystallinity were also observed. A more mineralized, less heterogeneous tissue may affect tissue-level mechanical properties and in turn degrade macroscale skeletal integrity. In conclusion, these data are the first evidence of progressive alteration of bone tissue composition with worsening glycemic control in humans. © 2020 American Society for Bone and Mineral Research (ASBMR). 相似文献
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A. Justin Nowakowski Janna R. Willoughby J. Andrew DeWoody Maureen A. Donnelly 《Conservation Genetics Resources》2014,6(3):697-698
There are relatively few molecular resources for amphibians in the tropics where widespread habitat loss, disease, and contamination threaten the world’s most diverse assemblages. We used Illumina sequencing to develop microsatellite primers for a dominant amphibian species in Costa Rica that has recently experienced population declines. We characterized 12 polymorphic loci and have provided sequences for over 200 additional primers. These novel molecular resources will be useful for future studies of population genetic structure and may help explain recent declines in one of many species that are decreasing in Central America. 相似文献
6.
Lauren T. Ptomey Amanda N. Szabo Erik A. Willis Anna M. Gorczyca J. Leon Greene Jessica C. Danon Joseph E. Donnelly 《Disability and health journal》2018,11(3):486-490
Background
Between 250,000 and 400,000 individuals in the United States are diagnosed with Down syndrome (DS). Nearly all adults with DS will develop Alzheimer's disease pathology starting in their thirties. Recent studies suggest that increased physical activity (PA) may be important for maintaining components of cognition, including memory.Objective
The purpose of this study was to evaluate changes in cognitive function after completion of a 12-week exercise intervention in adults with DS.Methods
Participants were randomized to attend 30-minute group exercise sessions 1 or 2 times a week for 12 weeks. The exercise sessions were delivered via video conferencing on a tablet computer to groups of 5–8 participants. Sessions consisted of aerobic based exercises such as walking and jogging to music, dancing, as well as strength based exercises such as vertical jumps, bicep curls, and squats. Cognitive function was measured at baseline and end of study using the Cantab Dementia Battery for iPads, which assessed the cognitive domains of memory, attention, and reaction time.Results
Twenty-seven participants (27.9?±?7.1 years of age, 40.7% female) enrolled and completed the 12-week intervention. Participants randomized to 1 session/week averaged 26.6?±?3.0?min/week of PA from the group exercise session. Participants randomized to 2 sessions/week averaged 57.7?±?15.3?min/week of PA from the group exercise sessions. Participants improved their performance on the two memory variables (p?=?0.048 and p?=?0.069).Conclusion
Increased exercise may have positive changes on memory and other cognitive functions. 相似文献7.
Lauren T. Ptomey Felicia L. Steger Jaehoon Lee Debra K. Sullivan Jeannine R. Goetz Jeffery J. Honas Richard A. Washburn Cheryl A. Gibson Joseph E. Donnelly 《Journal of the Academy of Nutrition and Dietetics》2018,118(6):1087-1096
Background
Previous research indicates that individuals with intellectual and developmental disabilities (IDDs) are at risk for poor diet quality.Objective
The purpose of this secondary analysis was to determine whether two different weight-loss diets affect energy intake, macronutrient intake, and diet quality as measured by the Healthy Eating Index-2010 (HEI-2010) during a 6-month weight-loss period and 12-month weight-management period, and to examine differences in energy intake, macronutrient intake, and HEI-2010 between groups.Design
Overweight/obese adults with IDDs took part in an 18-month randomized controlled trial and were assigned to either an enhanced Stop Light Diet utilizing portion-controlled meals or a conventional diet consisting of reducing energy intake and following the 2010 Dietary Guidelines for Americans. Proxy-assisted 3-day food records were collected at baseline, 6 months, and 18 months, and were analyzed using Nutrition Data System for Research software. HEI-2010 was calculated using the data from Nutrition Data System for Research.Participants/setting
The study took place from June 2011 through May 2014 in the greater Kansas City metropolitan area.Main outcome measures
This was a secondary analysis of a weight-management intervention for adults with IDDs randomized to an enhanced Stop Light Diet or conventional diet, to examine differences in energy intake, macronutrient intake, and HEI-2010 across time and between groups.Statistical analyses performed
Independent- and paired-samples t tests and general mixed modeling for repeated measures were performed to examine group differences and changes at baseline, 6 months, and 18 months between the enhanced Stop Light Diet and conventional diet groups.Results
One hundred and forty six participants (57% female, mean±standard deviation age=36.2±12.0 years) were randomized to either the enhanced Stop Light Diet or conventional diet group (77 enhanced Stop Light Diet, 69 conventional diet) and provided data for analysis at baseline, 124 completed the 6-month weight-loss period, and 101 completed the 18-month study. Participants on the enhanced Stop Light Diet diet significantly reduced energy intake at 6 and 18 months (both P<0.001), but those on the conventional diet did not (both P=0.13). However, when accounting for age, sex, race, education level, and support level (mild vs moderate IDD), there was a significant decrease during the 18-month intervention in energy intake for the enhanced Stop Light Diet and conventional diet groups combined (P<0.01 for time effect), but no significant group difference in this change (P=0.39 for group-by-time interaction). There was no significant change in total HEI-2010 score at 6 and 18 months (P=0.05 and P=0.38 for the enhanced Stop Light Diet group; P=0.22 and P=0.17 for the conventional diet group), and no significant group difference at 6 and 18 months (P=0.08 and P=0.42). However, when participants’ age, sex, race, education level, and support level were accounted for, mixed modeling indicated a significant increase in total HEI-2010 scores for the enhanced Stop Light Diet and conventional diet groups combined during the 18-month intervention (P=0.01 for time effect).Conclusions
The results of this study found that after controlling for demographic factors, individuals with IDDs can decrease their energy intake and increase their diet quality, with no significant differences between the enhanced Stop Light Diet and conventional diet groups. 相似文献8.
Iman M.N. Hamdan Ismaiel A. Tekko Kyle B. Matchett Luis G. Arnaut Claudia S. Silva Helen O. McCarthy Ryan F. Donnelly 《Journal of pharmaceutical sciences》2018,107(9):2439-2450
Nodular basal cell carcinoma is a deep skin lesion and one of the most common cancers. Conventional photodynamic therapy is limited to treatment of superficial skin lesions. The parenteral administration of near-IR preformed photosensitizers suffers from poor selectivity and may result in prolonged skin photosensitivity. Microneedles (MNs) can provide localized drug delivery to skin lesions. Intradermal delivery of the preformed near-IR photosensitizer; 5,10,15,20-tetrakis(2,6-difluoro-3-N-methylsulfamoylphenyl bacteriochlorin (Redaporfin?) using dissolving MN was successful in vitro and in vivo. MN demonstrated complete dissolution 30 min after skin application and showed sufficient mechanical strength to penetrate the skin to a depth of 450 μm. In vitro deposition studies illustrated that the drug was delivered and detected down to 5 mm in skin. In vivo biodistribution studies in athymic nude mice Crl:NU(NCr)-Foxn1nu showed both fast initial release and localized drug delivery. The MN-treated mice showed a progressive decrease in the fluorescence intensity at the application site over the 7-day experiment period, with the highest and lowest fluorescence intensities measured being 9.2 × 1010 ± 2.5 × 1010 and 3.8 × 109 ± 1.6 × 109 p/s, respectively. By day 7, there was some migration of fluorescence away from the site of initial MN application. However, the majority of the body surfaces showed fluorescence levels that were comparable to those seen in the negative control group. This work suggests utility for polymeric MN arrays in minimally invasive intradermal delivery to enhance photodynamic therapy of deep skin lesions. 相似文献
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Patrick E. Donnelly Laurianne Imbert Kirsty L. Culley Russell F. Warren Tony Chen 《Journal of biomaterials science. Polymer edition》2019,30(3):215-232
The optimal solution for articular cartilage repair has not yet been identified, in part because of the challenges in achieving integration with the host. Coatings have the potential to transform the adhesive features of surfaces, but their application to cartilage repair has been limited. Self-assembled monolayer of phosphonates (SAMPs) have been demonstrated to increase the adhesion of various immortalized cell types to metal and polymer surfaces, but their effect on primary chondrocyte adhesion has not been studied. The objective of this study was to investigate the response of primary chondrocytes to SAMP coatings. We hypothesized a SAMP terminated with an α,ω-bisphosphonic acid, in particular butane-1,4-diphosphonic acid, would increase the number of adherent primary chondrocytes to polyvinyl alcohol (PVA). To test our hypothesis, we first established our ability to successfully modify silicon dioxide (SiO2) surfaces to enable chondrocytes to attach to the surface, without substantial changes in gene expression. Secondly, we applied identical chemistry to PVA, and quantified chondrocyte adhesion. SAMP modification to SiO2 increased chondrocyte adhesion by ×3 after 4?hr and ×4.5 after 24?hr. PVA modification with SAMPs increased chondrocyte adhesion by at least ×31 after 4 and 24?hours. Changes in cell morphology indicated that SAMP modification led to improved chondrocyte adhesion and spreading, without changes in gene expression. In summary, we modified SiO2 and PVA with SAMPs and observed an increase in the number of adherent primary bovine chondrocytes at 4 and 24?hr post-seeding. Mechanisms of chondrocyte interaction with SAMP-modified surfaces require further investigation. 相似文献
10.
Tay FR Hiraishi N Schuster GS Pashley DH Loushine RJ Ounsi HF Grandini S Yau JY Mazzoni A Donnelly A King NM 《Journal of endodontics》2006,32(10):970-975
Potential intrinsic tetracycline staining of intraradicular dentin has been observed when BioPure MTAD was employed as the final irrigant after initial rinsing with NaOCl. This study examined the effect of NaOCl-MTAD interaction on the antimicrobial substantivity of MTAD in dentin. Dentin cores previously irrigated with either MTAD, or in conjunction with 1.3% NaOCl as an initial irrigant were placed on blood agar plates inoculated with Escherichia faecalis at 10(5) cfu/ml. Dentin cores irrigated with 1.3% NaOCl only, and autoclaved dentin disks were used as the respective positive and negative controls. After anaerobic incubation, the mean diameter of bacterial inhibition zones formed around the MTAD group was significantly larger than the NaOCl/MTAD group, which, in turn, was not significantly different from the NaOCl positive control. Oxidation of MTAD by NaOCl resulted in the partial loss of antimicrobial substantivity in a manner similar to the peroxidation of tetracycline by reactive oxygen species. 相似文献