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31.
Aim
To investigate RBC-NOS dependent NO signaling during in vivo RBC aging in health and disease.Method
RBC from fifteen healthy volunteers (HC) and four patients with type 2 diabetes mellitus (DM) were separated in seven subpopulations by Percoll density gradient centrifugation.Results
The proportion of old RBC was significantly higher in DM compared to HC. In both groups, in vivo aging was marked by changes in RBC shape and decreased cell volume. RBC nitrite, as marker for NO, was higher in DM and increased in both HC and DM during aging. RBC deformability was lower in DM and significantly decreased in old compared to young RBC in both HC and DM. RBC-NOS Serine1177 phosphorylation, indicating enzyme activation, increased during aging in both HC and DM. Arginase I activity remained unchanged during aging in HC. In DM, arginase I activity was significantly higher in young RBC compared to HC but decreased during aging. In HC, concentration of L-arginine, the substrate of RBC-NOS and arginase I, significantly dropped from young to old RBC. In DM, L-arginine concentration was significantly higher in young RBC compared to HC and significantly decreased during aging. In blood from healthy subjects, RBC-NOS activation was additionally inhibited by N5-(1-iminoethyl)-L-Ornithine dihydrochloride which decreased RBC nitrite, and impaired RBC deformability of all but the oldest RBC subpopulation.Conclusion
This study first-time showed highest RBC-NOS activation and NO production in old RBC, possibly to counteract the negative impact of cell shrinkage on RBC deformability. This was even more pronounced in DM. It is further suggested that highly produced NO only insufficiently affects cell function of old RBC maybe because of isolated RBC-NOS in old RBC thus decreasing NO bioavailability. Thus, increasing NO availability may improve RBC function and may extend cell life span in old RBC. 相似文献32.
33.
Froyen G Bauters M Boyle J Van Esch H Govaerts K van Bokhoven H Ropers HH Moraine C Chelly J Fryns JP Marynen P Gecz J Turner G 《Human genetics》2007,121(5):539-547
Using high resolution X chromosome array-CGH we identified an interstitial microdeletion at Xp11.23 in three brothers with
moderate to severe mental retardation (MR) without dysmorphic features. The extent of the deletion was subsequently delineated
to about 50 kb by regular PCR and included only the SLC38A5 and FTSJ1 genes. The loss of the FTSJ1 MR gene in males is expected to result in the observed phenotype but the contribution of the deletion of the solute carrier
SLC38A5 gene is less clear. Their mother also carries the deletion and completely inactivates the aberrant X chromosome. Interestingly,
the distal breakpoint is situated within a 200 kb SSX repeat region that appears to stimulate recombination since subtle copy
number changes often occur at this location and it is frequently involved in translocations in tumours. Since this apparent
SSX unstable structure is flanked proximally by FTSJ1 and PQBP1, subtle deletions or duplications at this location would be expected to cause MR, as in our family. So far, we have screened
a cohort of 300 patients but did not find additional aberrations at the FTSJ1 locus indicating that the frequency is likely to be low. 相似文献
34.
Social,contextual, and individual factors affecting the occurrence and acoustic structure of drumming bouts in wild chimpanzees (Pan troglodytes) 下载免费PDF全文
Magdalena Babiszewska Anne Marijke Schel Claudia Wilke Katie E. Slocombe 《American journal of physical anthropology》2015,156(1):125-134
The production of structured and repetitive sounds by striking objects is a behavior found not only in humans, but also in a variety of animal species, including chimpanzees (Pan troglodytes). In this study we examined individual and social factors that may influence the frequency with which individuals engage in drumming behavior when producing long distance pant hoot vocalizations, and analyzed the temporal structure of those drumming bouts. Male chimpanzees from Budongo Forest, Uganda, drummed significantly more frequently during travel than feeding or resting and older individuals were significantly more likely to produce drumming bouts than younger ones. In contrast, we found no evidence that the presence of estrus females, high ranking males and preferred social partners in the caller's vicinty had an effect on the frequency with which an individual accompanied their pant hoot vocalization with drumming. Through acoustic analyses, we demonstrated that drumming sequences produced with pant hoots may have contained information on individual identity and that qualitatively, there was individual variation in the complexity of the temporal patterns produced. We conclude that drumming patterns may act as individually distinctive long‐distance signals that, together with pant hoot vocalizations, function to coordinate the movement and spacing of dispersed individuals within a community, rather than as signals to group members in the immediate audience. Am J Phys Anthropol 156:125–134, 2015 © 2014 Wiley Periodicals, Inc. 相似文献
35.
Marijke Boorsma Dinnus H.M. Frijters Dirk L. Knol Miel E. Ribbe Giel Nijpels Hein P.J. van Hout 《CMAJ》2011,183(11):E724-E732
Background:
Sophisticated approaches are needed to improve the quality of care for elderly people living in residential care facilities. We determined the effects of multidisciplinary integrated care on the quality of care and quality of life for elderly people in residential care facilities.Methods:
We performed a cluster randomized controlled trial involving 10 residential care facilities in the Netherlands that included 340 participating residents with physical or cognitive disabilities. Five of the facilities applied multidisciplinary integrated care, and five provided usual care. The intervention, inspired by the disease management model, consisted of a geriatric assessment of functional health every three months. The assessment included use of the Long-term Care Facility version of the Resident Assessment Instrument by trained nurse-assistants to guide the design of an individualized care plan; discussion of outcomes and care priorities with the family physician, the resident and his or her family; and monthly multidisciplinary meetings with the nurse-assistant, family physician, psychologist and geriatrician to discuss residents with complex needs. The primary outcome was the sum score of 32 risk-adjusted quality-of-care indicators.Results:
Compared with the facilities that provided usual care, the intervention facilities had a significantly higher sum score of the 32 quality-of-care indicators (mean difference − 6.7, p = 0.009; a medium effect size of 0.72). They also had significantly higher scores for 11 of the 32 indicators of good care in the areas of communication, delirium, behaviour, continence, pain and use of antipsychotic agents.Interpretation:
Multidisciplinary integrated care resulted in improved quality of care for elderly people in residential care facilities compared with usual care.Trial registration:
www.controlled-trials.com trial register no. ISRCTN11076857.The quality of care provided in residential care facilities is under pressure worldwide.1 Facilities are frequently understaffed, and the complexity of care needed by residents increases while expertise of staff does not necessarily keep pace.2,3 Although most care organizations want to innovate and improve quality of care, many lack expertise or financial resources needed to do so.4,5 Family physicians are responsible for medical care in residential care facilities in the Netherlands. However, they do not regard themselves as suited for systematic management of chronic diseases and disabilities associated with frail health.6About 10% of elderly people aged 75 or older in the Netherlands live in residential care facilities.7,8 These facilities were established to offer sheltered living for elderly people who are disabled but still relatively healthy. Because of the growing elderly population, the characteristics of elderly people living in residential care facilities have become more comparable to those of people in nursing homes, who need complex care. Residential care facilities in the Netherlands are comparable to residential care facilities in Canada, are publicly funded and are subject to government inspection and approval. Over 70% of the residents need professional care, such as assistance with activities of daily living, nursing care (e.g., medication, wound care) and housekeeping. They have multiple chronic diseases and associated disabilities.9–12Effective interventions for chronic illnesses generally rely on a multidisciplinary team approach. The elements of this approach include structured geriatric assessment, protocol-based regulation of medications, support for self-reliance and intensive follow-up. The closely related disease management model comprises coordination of care, steering of the care process and patient empowerment.13 This model is strongly recommended by Bodenheimer and colleagues to improve the health and quality of life of chronically ill patients.14 However, no studies have as yet been undertaken to evaluate the effects of disease management on functional health and quality of care for elderly people in residential care facilities who have physical or cognitive disabilities.We developed an approach to multidisciplinary integrated care inspired by the disease management model. The objective of our study was to determine the effects of multidisciplinary integrated care on quality of care and quality of life for elderly people in residential care facilities. 相似文献36.
Mould routine identification in the clinical laboratory by matrix-assisted laser desorption ionization time-of-flight mass spectrometry 总被引:1,自引:0,他引:1
Cassagne C Ranque S Normand AC Fourquet P Thiebault S Planard C Hendrickx M Piarroux R 《PloS one》2011,6(12):e28425
Background
MALDI-TOF MS recently emerged as a valuable identification tool for bacteria and yeasts and revolutionized the daily clinical laboratory routine. But it has not been established for routine mould identification. This study aimed to validate a standardized procedure for MALDI-TOF MS-based mould identification in clinical laboratory.Materials and Methods
First, pre-extraction and extraction procedures were optimized. With this standardized procedure, a 143 mould strains reference spectra library was built. Then, the mould isolates cultured from sequential clinical samples were prospectively subjected to this MALDI-TOF MS based-identification assay. MALDI-TOF MS-based identification was considered correct if it was concordant with the phenotypic identification; otherwise, the gold standard was DNA sequence comparison-based identification.Results
The optimized procedure comprised a culture on sabouraud-gentamicin-chloramphenicol agar followed by a chemical extraction of the fungal colonies with formic acid and acetonitril. The identification was done using a reference database built with references from at least four culture replicates. For five months, 197 clinical isolates were analyzed; 20 were excluded because they were not identified at the species level. MALDI-TOF MS-based approach correctly identified 87% (154/177) of the isolates analyzed in a routine clinical laboratory activity. It failed in 12% (21/177), whose species were not represented in the reference library. MALDI-TOF MS-based identification was correct in 154 out of the remaining 156 isolates. One Beauveria bassiana was not identified and one Rhizopus oryzae was misidentified as Mucor circinelloides.Conclusions
This work''s seminal finding is that a standardized procedure can also be used for MALDI-TOF MS-based identification of a wide array of clinically relevant mould species. It thus makes it possible to identify moulds in the routine clinical laboratory setting and opens new avenues for the development of an integrated MALDI-TOF MS-based solution for the identification of any clinically relevant microorganism. 相似文献37.
Salmonella survives in macrophages by using a molecular syringe to deliver proteins into the host-cell cytosol where they manipulate phagocyte physiology. Arpaia and colleagues (Arpaia et?al., 2011) show that deployment of this virulence factor is triggered by the very responses that are intended to confer host resistance. 相似文献
38.
De Mey JG Schiffers PM Hilgers RH Sanders MM 《American journal of physiology. Heart and circulatory physiology》2005,288(3):H1022-H1027
In resistance-sized arteries, a chronic increase in blood flow leads to increases in arterial structural luminal diameter and arterial wall mass. In this review, we summarize recent evidence that outward remodeling of resistance arteries 1) can help maintain and restore tissue perfusion, 2) is not intimately related to flow-induced vasodilatation, 3) involves transient dedifferentiation and turnover of arterial smooth muscle cells, and 4) is preceded by increased expression of matricellular proteins, which have been shown to promote disassembly of focal adhesion sites. Studies of experimental and physiological resistance artery remodeling involving differential gene expression analyses and the use of knockout and transgenic mouse models can help unravel the mechanisms of outward remodeling. 相似文献
39.
40.
We report on results from an Internet survey of sleeping habits in a Dutch population using the Munich Chronotype Questionnaire (MCTQ), supplemented with the Horne-Ostberg Morningness-Eveningness Questionnaire (MEQ). The MCTQ was completed by 5,055 responders, of which 2,481 also completed the MEQ. MEQ score correlated well with the MCTQ assessment of time of mid-sleep on free days (MSF; r = - 0.73) and on workdays (MSW; r = - 0.61). MEQ was more strongly correlated with MSF (50% of sleep time) than with sleep onset (0%), rise time (100%), or with any other percentile (10 to 40, 60% to 90%) of sleep on free days. The study shows that chronotype (based on MSF as measured by the MCTQ) strongly correlates with morningness-eveningness (as measured by the MEQ). However, the MCTQ collects additional detailed information on sleep-wake behavior under natural conditions. 相似文献