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111.
Adele Costabile Sara Santarelli Sandrine P. Claus Jeremy Sanderson Barry N. Hudspith Jonathan Brostoff Jane L. Ward Alison Lovegrove Peter R. Shewry Hannah E. Jones Andrew M. Whitley Glenn R. Gibson 《PloS one》2014,9(10)
A variety of foods have been implicated in symptoms of patients with Irritable Bowel Syndrome (IBS) but wheat products are most frequently cited by patients as a trigger. Our aim was to investigate the effects of breads, which were fermented for different lengths of time, on the colonic microbiota using in vitro batch culture experiments. A set of in vitro anaerobic culture systems were run over a period of 24 h using faeces from 3 different IBS donors (Rome Criteria–mainly constipated) and 3 healthy donors. Changes in gut microbiota during a time course were identified by fluorescence in situ hybridisation (FISH), whilst the small -molecular weight metabolomic profile was determined by NMR analysis. Gas production was separately investigated in non pH-controlled, 36 h batch culture experiments. Numbers of bifidobacteria were higher in healthy subjects compared to IBS donors. In addition, the healthy donors showed a significant increase in bifidobacteria (P<0.005) after 8 h of fermentation of a bread produced using a sourdough process (type C) compared to breads produced with commercial yeasted dough (type B) and no time fermentation (Chorleywood Breadmaking process) (type A). A significant decrease of δ-Proteobacteria and most Gemmatimonadetes species was observed after 24 h fermentation of type C bread in both IBS and healthy donors. In general, IBS donors showed higher rates of gas production compared to healthy donors. Rates of gas production for type A and conventional long fermentation (type B) breads were almost identical in IBS and healthy donors. Sourdough bread produced significantly lower cumulative gas after 15 h fermentation as compared to type A and B breads in IBS donors but not in the healthy controls. In conclusion, breads fermented by the traditional long fermentation and sourdough are less likely to lead to IBS symptoms compared to bread made using the Chorleywood Breadmaking Process. 相似文献
112.
Staci L. Solin Ying Wang Joshua Mauldin Laura E. Schultz Deborah E. Lincow Pavel A. Brodskiy Crystal A. Jones Judith Syrkin-Nikolau Jasmine M. Linn Jeffrey J. Essner Jesse M. Hostetter Elizabeth M. Whitley J. Douglas Cameron Hui-Hsien Chou Andrew J. Severin Donald S. Sakaguchi Maura McGrail 《PloS one》2014,9(12)
113.
Nicole Willems Frances C Bach Saskia G M Plomp Mattie HP van Rijen Jeannette Wolfswinkel Guy CM Grinwis Clemens Bos Gustav J Strijkers Wouter JA Dhert Bj?rn P Meij Laura B Creemers Marianna A Tryfonidou 《Arthritis research & therapy》2015,17(1)
IntroductionStrategies for biological repair and regeneration of the intervertebral disc (IVD) by cell and tissue engineering are promising, but few have made it into a clinical setting. Recombinant human bone morphogenetic protein 7 (rhBMP-7) has been shown to stimulate matrix production by IVD cells in vitro and in vivo in animal models of induced IVD degeneration. The aim of this study was to determine the most effective dose of an intradiscal injection of rhBMP-7 in a spontaneous canine IVD degeneration model for translation into clinical application for patients with low back pain.MethodsCanine nucleus pulposus cells (NPCs) were cultured with rhBMP-7 to assess the anabolic effect of rhBMP-7 in vitro, and samples were evaluated for glycosaminoglycan (GAG) and DNA content, histology, and matrix-related gene expression. Three different dosages of rhBMP-7 (2.5 μg, 25 μg, and 250 μg) were injected in vivo into early degenerated IVDs of canines, which were followed up for six months by magnetic resonance imaging (T2-weighted images, T1rho and T2 maps). Post-mortem, the effects of rhBMP-7 were determined by radiography, computed tomography, and macroscopy, and by histological, biochemical (GAG, DNA, and collagen), and biomolecular analyses of IVD tissue.ResultsIn vitro, rhBMP-7 stimulated matrix production of canine NPCs as GAG deposition was enhanced, DNA content was maintained, and gene expression levels of ACAN and COL2A1 were significantly upregulated. Despite the wide dose range of rhBMP-7 (2.5 to 250 μg) administered in vivo, no regenerative effects were observed at the IVD level. Instead, extensive extradiscal bone formation was noticed after intradiscal injection of 25 μg and 250 μg of rhBMP-7.ConclusionsAn intradiscal bolus injection of 2.5 μg, 25 μg, and 250 μg rhBMP-7 showed no regenerative effects in a spontaneous canine IVD degeneration model. In contrast, intradiscal injection of 250 μg rhBMP-7, and to a lesser extent 25 μg rhBMP-7, resulted in extensive extradiscal bone formation, indicating that a bolus injection of rhBMP-7 alone cannot be used for treatment of IVD degeneration in human or canine patients.
Electronic supplementary material
The online version of this article (doi:10.1186/s13075-015-0625-2) contains supplementary material, which is available to authorized users. 相似文献114.
Increasing awareness of the possible role of internal dynamics in protein function has led to the development of new methods for experimentally characterizing protein dynamics across multiple time scales, especially using NMR spectroscopy. A few analyses of the conformational dynamics of proteins ranging from nonallosteric single domains to multidomain allosteric enzymes are now available; however, demonstrating a connection between dynamics and function remains difficult on account of the comparative lack of studies examining both changes in dynamics and changes in function in response to the same perturbations. In previous work, we characterized changes in structure and dynamics on the ps–ns time scale resulting from hydrophobic core mutations in chymotrypsin inhibitor 2 and found that there are moderate, persistent global changes in dynamics in the absence of gross structural changes (Whitley et al., Biochemistry 2008;47:8566–8576). Here, we assay those and additional mutants for inhibitory ability toward the serine proteases elastase and chymotrypsin to determine the effects of mutation on function. Results indicate that core mutation has only a subtle effect on CI2 function. Using chemical shifts, we also studied the effect of complex formation on CI2 structure and found that perturbations are greatest at the complex interface but also propagate toward CI2's hydrophobic core. The structure–dynamics–function data set completed here suggests that dynamics plays a limited role in the function of this small model system, although we do observe a correlation between nanosecond-scale reactive loop motions and inhibitory ability for mutations at one key position in the hydrophobic core. 相似文献
115.
Hyper-activation of DNA repair pathways can enable tumor cells to survive DNA damage. Therefore, targeting specific DNA repair pathways might prove efficacious for cancer therapy. The advent of personalized therapy necessitates novel biomarkers to assess tumor response to therapy. Biological indicators are vital in the field of cancer research and treatment. The focus of this review is on the DNA repair machinery as an emerging target for enhancement of therapy. Additionally, DNA damage and repair biomarkers for prognosis in different types of cancer will be discussed. The application of biomarkers to assess tumor response to therapy based on targeting DNA repair pathways can potentially improve patient quality of life and aid in treatment design. 相似文献
116.
Background
The adverse effects of advancing maternal age on offspring''s health and development are well understood. Much less is known about the impact of paternal age.Methods
We explored paternal age-offspring cognition associations in 772 participants from the West of Scotland Twenty-07 study. Offspring cognitive ability was assessed using Part 1 of the Alice Heim 4 (AH4) test of General Intelligence and by reaction time (RT).Results
There was no evidence of a parental age association with offspring RT. However, we observed an inverse U-shaped association between paternal age and offspring AH4 score with the lowest scores observed for the youngest and oldest fathers. Adjustment for parental education and socioeconomic status somewhat attenuated this association. Adjustment for number of, particularly older, siblings further reduced the scores of children of younger fathers and appeared to account for the lower offspring scores in the oldest paternal age group.Conclusion
We observed a paternal age association with AH4 but not RT, a measure of cognition largely independent of social and educational experiences. Factors such as parental education, socioeconomic status and number of, particularly older, siblings may play an important role in accounting for paternal age-AH4 associations. Future studies should include parental intelligence. 相似文献117.
Haff GG Whitley A McCoy LB O'Bryant HS Kilgore JL Haff EE Pierce K Stone MH 《Journal of strength and conditioning research / National Strength & Conditioning Association》2003,17(1):95-103
The effects of 3 types of set configurations (cluster, traditional, and undulating) on barbell kinematics were investigated in the present study. Thirteen men (track and field = 8; Olympic weightlifters = 5) (mean +/- SEM age, 23.4 +/- 1.1 years; height, 181.3 +/- 2.1 cm; body mass, 89.8 +/- 4.2 kg) performed 1 set of 5 repetitions in a cluster, traditional, and undulating fashion at 90 and 120% of their 1 repetition maximum (1RM) power clean (119.0 +/- 4.3 kg). All data were collected at 50 Hz and analyzed with a V-Scope Weightlifting Analysis System. Peak velocity (PV) and peak displacement (PD) were analyzed for each repetition and averaged for each set type. Results indicated that a significantly (p < 0.016) higher PV occurred during the cluster set when compared with the traditional sets at both intensities. PD was significantly higher than traditional sets at the 120% intensity. The present study suggests set configuration can affect PV and PD during clean pulls. 相似文献
118.
BACKGROUND: One of the major barriers to the clinical application of hematopoietic stem cell (HSC) gene therapy has been relatively low gene transfer efficiency. Other inadequacies of current transduction protocols are related to their multi-step procedures, e.g., using tissue-culture flasks, roller bottles or gas-permeable bags for clinical application. METHODS: In comparison with a conventional bag transduction protocol, a 'closed' hollow-fiber bioreactor system (HBS) was exploited to culture and transduce human peripheral blood CD34(+) progenitor cells (PBPC(MPS)) from patients with mucopolysaccharidosis type I (MPS I) using an amphotropic retroviral vector based on a murine Moloney leukemia virus LN prototype. Both short-term colony-forming cell (CFC) and long-term culture initiating cell (LTCIC) assays were employed to determine transduction frequency and transgene expression in committed progenitor cells and primitive progenitors with multi-lineage potentials. RESULTS: A novel ultrafiltration-transduction method was established to culture and transduce enzyme-deficient PBPC(MPS) over a 5-day period without loss in viability and CD34 identity (n = 5). Significantly higher transduction efficiencies were achieved in primary CFC that derived from the HBS (5.8-14.2%) in comparison with those from gas-permeable bags (undetectable to 1.7%; p < 0.01). Up to 15-fold higher-than-normal enzyme activity was found in selected PBPC(MPS)-LP1CD transductants. Moreover, higher gene transfer (4.4-fold) and expression in very primitive progenitors were observed in products from the HBS compared with bag experiments as indicated by CFC derived from primitive LTCIC. Remarkably, with relatively modest gene transfer levels in LTCIC from HBS experiments, the expression of the IDUA transgene corrected the enzyme-deficiency in 5-week long-term cultures (LTC). CONCLUSIONS: MPS I progenitor cells achieved normalized enzyme levels in LTC after transduction in a HBS system. These studies demonstrate the advantages of a bioreactor-transduction system for viral-mediated stem cell gene transfer. 相似文献
119.
120.