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991.

Background

There are few systematic studies on the prevalence of sarcopenia using the new diagnostic criteria in different geriatric care settings.

Objective

To estimate the prevalence of sarcopenia, using the European Working Group on Sarcopenia in Older People (EWGSOP) criteria in older subjects living in nursing homes and in those who attend geriatric outpatient clinics.

Material and methods

A single country multicentre study in two samples of older subjects: patients cared for in outpatient geriatric clinics, and individuals living in nursing homes. Data collected will include demographic variables, medical history, medication, geriatric syndromes, functional status (assessment of basic and instrumental activities of daily living), mobility, cognitive status, comorbidity, quality of life, nutritional status, and laboratory parameters. For the diagnosis of sarcopenia, 4 m walking speed, handgrip strength, and body composition measured by bioelectrical impedance analysis will be assessed.

Results

Using the EWGSOP algorithm, the prevalence of sarcopenia in an elderly Spanish population will be estimated. In addition, concordance and correlation between the three parameters included in the definition (muscle mass, muscle strength, and physical performance) will be analysed, using the different existing cut-off points, and examining the diagnostic accuracy of each. Finally, demographic, anthropometric and functional data that define subjects with sarcopenia will be investigated.

Conclusions

The ELLI study should improve knowledge on the prevalence and characteristics of sarcopenia in older people in our population.  相似文献   
992.
993.

Background

Cancer immunoediting is a dynamic process composed of three phases: elimination (EL), equilibrium (EQ) and escape (ES) that encompasses the potential host-protective and tumor-sculpting functions of the immune system throughout tumor development. Animal models are useful tools for studying diseases such as cancer. The present study was designed to characterize the interaction between mammary adenocarcinoma M-406 and CBi, CBi and CBi/L inbred mice lines.

Results

The mammary adenocarcinoma M-406 developed spontaneously in a CBi mouse. CBi/L and CBi mice were artificially selected for body conformation from CBi. When CBi mice are s.c. challenged with M-406, tumor growths exponentially in 100% of animals, while in CBi the tumor growths briefly and then begins a rejection process in 100% of the animals. In CBi/L the growth of the tumor shows the three phases: 51.6% in ES, 18.5% in EQ and 29.8% in EL.

Conclusions

The results obtained support the conclusion that the system M-406 plus the inbred mouse lines CBi, CBi and CBi/L, is a good murine model to study the process of tumor immunoediting.  相似文献   
994.
Natural colchicinoids and their semisynthetic derivatives are important active ingredients for pharmaceutical applications. Thiocolchicoside (3-demethoxy-3-glucosyloxythiocolchicine) is used in several countries as standard therapy for the treatment of diseases of the muscle–skeletal system, due to its potent antiinflammatory and myorelaxant properties. Manufacturing of thiocolchicoside requires a key step, the regioselective demethylation and glucosylation of chemically derivative thiocolchicine. High selectivity and efficiency of this transformation cannot be achieved in a satisfactory way with a chemical approach. In particular, the chemical demethylation, a part from requiring toxic and aggressive reagents, generates a complex mixture of products with no industrial usefulness. We report herein an efficient, direct and green biotransformation of thiocolchicine into thiocolchicoside, performed by a specific strain of Bacillus megaterium. The same process, with minor modifications, can be used to convert the by-product 3-O-demethyl-thiocolchicine into thiocolchicoside. In addition, we describe the B. megaterium strain selection process and the best conditions for this effective double biotransformation. The final product has a pharmaceutical quality, and the process has been industrialised.  相似文献   
995.
The role of horizontal and vertical colonization on the diversity and integration of the dung beetle fauna of two mountains in the Mexican Transition Zone (Los Tuxtlas and La Chinantla) are analyzed and compared. On each mountain standardized sampling was done using pitfall traps baited with dung and carrion along elevation gradients. On both mountains diversity decreased linearly with increasing elevation. The decrease in the number of genera and species was not different between mountains, but the cumulative total number for both taxonomic levels was significantly higher on La Chinantla. There, three well-defined groups were identified for which species turnover was mainly a result of species gain. On Los Tuxtlas there was no evident grouping pattern, and species turnover was determined by species loss. For both mountains the dominant biogeographic distribution pattern was Neotropical; however, at the higher elevations of La Chinantla, a clear replacement by lineages of Holarctic affinity was observed. We suggest that for La Chinantla—a mountain that is geographically connected to the Sierra Madre Oriental mountain range and is of ancient geological origin—the processes of horizontal and vertical colonization have had relatively different weights in terms of their effect on the pattern of diversity and the biogeographic integration of the beetle community, while on Los Tuxtlas, the limited role of horizontal colonization appears to be a consequence of its isolation and more recent geological origin. We discuss the potential use of these models for studying the effects of climate change on elevation gradients.  相似文献   
996.
997.
Epidemiological studies and clinical trials revealed that chronic consumption coffee is associated with the inhibition of several metabolic diseases as well as reduction in overall and cause-specific mortality. We show that both natural and decaffeinated brands of coffee similarly rapidly trigger autophagy in mice. One to 4 h after coffee consumption, we observed an increase in autophagic flux in all investigated organs (liver, muscle, heart) in vivo, as indicated by the increased lipidation of LC3B and the reduction of the abundance of the autophagic substrate sequestosome 1 (p62/SQSTM1). These changes were accompanied by the inhibition of the enzymatic activity of mammalian target of rapamycin complex 1 (mTORC1), leading to the reduced phosphorylation of p70S6K, as well as by the global deacetylation of cellular proteins detectable by immunoblot. Immunohistochemical analyses of transgenic mice expressing a GFP–LC3B fusion protein confirmed the coffee-induced relocation of LC3B to autophagosomes, as well as general protein deacetylation. Altogether, these results indicate that coffee triggers 2 phenomena that are also induced by nutrient depletion, namely a reduction of protein acetylation coupled to an increase in autophagy. We speculate that polyphenols contained in coffee promote health by stimulating autophagy.  相似文献   
998.
999.

Introduction

It has been shown that mortality rates of coeliac patients correlate with age at diagnosis of coeliac disease, diagnostic delay for coeliac disease, pattern of clinical presentation and HLA typing. Our aim was to create a tool that identifies coeliac patients at higher risk of developing complications.

Methods

To identify predictors of complications in patients with coeliac disease, we organised an observational multicenter case-control study based on a retrospective collection of clinical data. Clinical data from 116 cases (patients with complicated coeliac disease) and 181 controls (coeliac patients without any complications) were collected from seven European centres. For each case, one or two controls, matched to cases according to the year of assessment, gender and age, were selected. Diagnostic delay, pattern of clinical presentation, HLA typing and age at diagnosis were used as predictors.

Results

Differences between cases and controls were detected for diagnostic delay and classical presentation. Conditional logistic models based on these statistically different predictors allowed the development of a score system. Tertiles analysis showed a relationship between score and risk of developing complications.

Discussion

A score that shows the risk of a newly diagnosed coeliac patient developing complications was devised for the first time. This will make it possible to set up the follow-up of coeliac patients with great benefits not only for their health but also for management of economic resources.

Conclusions

We think that our results are very encouraging and represent the first attempt to build a prognostic score for coeliac patients.  相似文献   
1000.
DCs act as sentinel cells against incoming pathogens and represent the most potent antigen presenting cells, having the unique capability to prime naïve T cells. In addition to their role in induction of adaptive immune responses, DC are also able to activate innate cells as γδ T cells; in particular, a reciprocal crosstalk between DC and γδ T cells was demonstrated. However, whether HIV infection may alter DC-Vγ9Vδ2 T cells cross-talk was not yet described. To clarify this issue, we cultured activated Vγ9Vδ2 T cells with HIV infected monocyte derived DC (MoDC). After 5 days we evaluated MoDC phenotype, and Vγ9Vδ2 T cells activation and proliferation. In our model, Vγ9Vδ2 T cells were not able to proliferate in response to HIV-infected MoDC, although an up-regulation of CD69 was observed. Upon phosphoantigens stimulation, Vγ9Vδ2 T cells proliferation and cytokine production were inhibited when cultured with HIV-infected MoDC in a cell-contact dependent way. Moreover, HIV-infected MoDC are not able to up-regulate CD86 molecules when cultured with activated Vγ9Vδ2 T cells, compared with uninfected MoDC. Further, activated Vγ9Vδ2 T cells are not able to induce HLA DR up-regulation and CCR5 down-regulation on HIV-infected MoDC. These data indicate that HIV-infected DC alter the capacity of Vγ9Vδ2 T cells to respond to their antigens, pointing out a new mechanisms of induction of Vγ9Vδ2 T cells anergy carried out by HIV, that could contribute to immune evasion.  相似文献   
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