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51.
52.
Kate L Holliday Wendy Thomson Tuhina Neogi David T Felson Ke Wang Frederick C Wu Ilpo T Huhtaniemi Gyorgy Bartfai Felipe Casanueva Gianni Forti Krzysztof Kula Margus Punab Dirk Vanderschueren Gary J Macfarlane Michael A Horan William Ollier Antony Payton Neil Pendleton John McBeth 《Molecular pain》2012,8(1):1-5
Background
Chronic pain conditions are characterized by significant individual variability complicating the identification of pathophysiological markers. Leukocyte telomere length (TL), a measure of cellular aging, is associated with age-related disease onset, psychosocial stress, and health-related functional decline. Psychosocial stress has been associated with the onset of chronic pain and chronic pain is experienced as a physical and psychosocial stressor. However, the utility of TL as a biological marker reflecting the burden of chronic pain and psychosocial stress has not yet been explored.Findings
The relationship between chronic pain, stress, and TL was analyzed in 36 ethnically diverse, older adults, half of whom reported no chronic pain and the other half had chronic knee osteoarthritis (OA) pain. Subjects completed a physical exam, radiographs, health history, and psychosocial questionnaires. Blood samples were collected and TL was measured by quantitative polymerase chain reaction (qPCR). Four groups were identified characterized by pain status and the Perceived Stress Scale scores: 1) no pain/low stress, 2) no pain/high stress, chronic pain/low stress, and 4) chronic pain/high stress. TL differed between the pain/stress groups (p = 0.01), controlling for relevant covariates. Specifically, the chronic pain/high stress group had significantly shorter TL compared to the no pain/low stress group. Age was negatively correlated with TL, particularly in the chronic pain/high stress group (p = 0.03).Conclusions
Although preliminary in nature and based on a modest sample size, these findings indicate that cellular aging may be more pronounced in older adults experiencing high levels of perceived stress and chronic pain. 相似文献53.
A conceptual framework is developed and used for improving the livelihood of Sub-Saharan communities faced with multiple stresses
resulting from adverse environments, vector-transmitted diseases, and limited food. Ecosocial systems are the units for management.
The accumulation of ecological, economic, and social capital is the objective of management, the reduction of maintenance
costs is the key strategy, and technologies must satisfy ecological, economic, and social criteria. Interacting social system
components are communities, facilitators, scientists, and political as well as administrative organizations. An adaptive approach
to management allows flexibility in human and financial resource allocation and results in changes in knowledge and efficacy
of management operations. The implementation strategy at two sites in Ethiopia relies on a two-stage procedure. In Stage 1,
human and cattle health management set the conditions for development. In Stage 2, the ecosocial system is kept on a trajectory
to enhanced ecological, economic, and social capital. In each stage, the assignment of responsibilities leads to four implementation
phases. In Stage 1, successful precision targeting of tsetse and drug-based Trypanosoma spp. control increased the economic and social capital at the Luke site in southwestern Ethiopia but threatened the ecological
capital because of overstocking and land degradation. In Stage 2, a women’s group living in the outskirts of Addis Ababa (Ethiopia)
transformed barren land into a horticultural enterprise to enhance ecosystem service provision, including production of horticultural
goods, and increase soil fertility expressed by nutrients and water availability. This article reviews concepts on human livelihood
improvement in Sub-Saharan Africa and identifies principles that became important during project execution. 相似文献
54.
Chiara Salvesi Stefania Silvi Dennis Fiorini Serena Scortichini Gianni Sagratini Francesco A. Palermo Renato De Leone Nadaniela Egidi Lorella Fatone Carlo Cifani Amedeo Amedei Francesca Scocchera Mara Morici Beatrice Gatto Fausto Mannucci Valerio Valeriani Marco Malavasi Sara Servili Andrea Casula Andrea Cresci Ivano Corradetti Francesco Carpi Matteo Picciolini Maria Magdalena Coman Maria Cristina Verdenelli 《Journal of applied microbiology》2022,133(5):2941-2953
55.
Pazzagli L Pantera B Carresi L Zoppi C Pertinhez TA Spisni A Tegli S Scala A Cappugi G 《Cell biochemistry and biophysics》2006,44(3):512-521
The ascomcete Ceratocystis fimbriata, the causal agent of “canker stain disease,” secretes a protein of 12.4 kDa that elicits phytoalexin synthesis and plant
cell death. This protein, named cerato-platanin (CP), is also located in the cell walls of ascospores, hyphae, and conidia;
it contains four cysteines (S-S bridged) and is moderately hydrophobic. The cp gene consists of a single exon and has 42 bp codifying for a signal peptide of 14 residues. The recombinant protein was obtained
by cloning the cp gene of the mature protein in Escherichia coli (BL21), and a refolding step was needed to achieve the native active form. In the European Molecular Biology data bank, CP
is reported as the first member of the CP family; this is the first example of an set of secreted fungal proteins whose primary
structure is very similar. Nonetheless, the data also revealed some structural and functional features that make CP simlar
to proteins of the hydrophobin family. 相似文献
56.
57.
Federico Mussano Alberto Bartorelli Cusani Alessia Brossa Stefano Carossa Gianni Bussolati 《Bioscience, biotechnology, and biochemistry》2013,77(4):662-671
New approaches in the treatment of skeletal defects may benefit from the use of soluble biological factors. We previously standardized a derivative of bovine colostrum (SBCD), deprived of casein and fat and rich in cytokines. In the present study, we tested its possible use as an adjuvant in bone healing. SBCD contained factors involved in stromal cell stimulation and differentiation and induced cytokine production from stimulated mesenchymal stem cells (MSCs). In vitro, SBCD promoted proliferation, migration and, in association with osteogenic factors, osteogenic differentiation of osteoblastic and MSCs. In in vivo experiments of subcutaneous Matrigel injection in mice, SBCD plus hydroxyapatite, but not hydroxyapatite nor SBCD alone, induced recruitment of macrophages and stromal cells. After 60?days, plugs containing SBCD and hydroxyapatite were densely calcified and diffusely positive for osteocalcin, supporting the occurrence of an early osteogenic process. These results indicate that SBCD is a rich source of factors with osteoinductive properties. 相似文献
58.
Peptide nucleic acids are DNA mimics able to form duplexes with complementary DNA or RNA strands of remarkable affinity and selectivity. Oligopyrimidine PNA can displace one strand of dsDNA by forming PNA(2):DNA triplexes of very high stability. Many PNA analogs have been described in recent years, in particular, chiral PNA analogs. In the present article the results obtained recently using PNA derived from N-aminoethylamino acids 7 are illustrated. In particular, the dependence of optical purity on synthetic methodologies and a rationale for the observed effects of chirality on DNA binding ability is proposed. Chirality as a tool for improving sequence selectivity is also described. PNA analogs derived from D- or L-ornithine 8 were also found to be subjected to epimerization during solid phase synthesis. Modification of the coupling conditions or the use of a submonomeric strategy greatly reduced epimerization. The optically pure oligothymine PNAs 8 were found to bind to RNA by forming triplexes of unusual CD spectra. The melting curves of these adducts presented two transitions, suggesting a conformational change followed by melting at high temperature. 相似文献
59.
60.
Microtubule defects in mesenchymal stromal cells distinguish patients with Progressive Supranuclear Palsy 下载免费PDF全文
Alessandra Maria Calogero Mariele Viganò Silvia Budelli Daniela Galimberti Chiara Fenoglio Daniele Cartelli Lorenza Lazzari Petri Lehenkari Margherita Canesi Rosaria Giordano Graziella Cappelletti Gianni Pezzoli 《Journal of cellular and molecular medicine》2018,22(5):2670-2679
Progressive Supranuclear Palsy (PSP) is a rare neurodegenerative disease whose etiopathogenesis remains elusive. The intraneuronal accumulation of hyperphosphorylated Tau, a pivotal protein in regulating microtubules (MT), leads to include PSP into tauopathies. Pathological hallmarks are well known in neural cells but no word yet if PSP‐linked dysfunctions occur also in other cell types. We focused on bone marrow mesenchymal stromal cells (MSCs) that have recently gained attention for therapeutic interventions due to their anti‐inflammatory, antiapoptotic and trophic properties. Here, we aimed to investigate MSCs biology and to disclose if any disease‐linked defect occurs in this non‐neuronal compartment. First, we found that cells obtained from patients showed altered morphology and growth. Next, Western blotting analysis unravelled the imbalance in α‐tubulin post‐translational modifications and in MT stability. Interestingly, MT mass is significantly decreased in patient cells at baseline and differently changes overtime compared to controls, suggesting their inability to efficiently remodel MT cytoskeleton during ageing in culture. Thus, our results provide the first evidence that defects in MT regulation and stability occur and are detectable in a non‐neuronal compartment in patients with PSP. We suggest that MSCs could be a novel model system for unravelling cellular processes implicated in this neurodegenerative disorder. 相似文献