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141.
142.

Background

High dietary sugar intake may compromise protein and micronutrient intakes in people with low energy intakes. The results of micronutrient dilution studies in older people have been few and conflicting. We examined the nutritional status and nutrient intakes associated with nonmilk extrinsic sugars (NMES) intakes in older people representing a broad spectrum of both healthy and vulnerable older populations.

Design and participants

This cross-sectional study combined five Finnish data sets covering home-dwelling (n = 526) and institutionalized (n = 374) older people. Their nutritional status was assessed using Mini Nutritional Assessment (MNA) and nutrient intakes retrieved from 1- to 3-day food records. The participants were divided into quartiles corresponding to the proportions of energy received from NMES. Energy, nutrient, and fiber intakes were classified according to the NMES quartiles, and the participants were divided according to their places of residence (home, institution).

Results

High NMES intakes were associated with older age, female sex, poor cognition, low MNA scores, immobility, and institutionalization. In all, 90% of the participants in the highest NMES quartile (Q4) were institutionalized. In the institutionalized individuals, low protein and micronutrient intakes were observed in both those with low energy intake (Q1) and in those with very high NMES intakes (Q4). In home-dwelling individuals, the nutrient intakes tended to decline linearly with increasing NMES intakes in protein and most micronutrients.

Conclusions

Institutionalized older people consumed diets high in NMES, compared with those living at home, and their low energy and high NMES intakes were associated with low protein and micronutrient intakes.  相似文献   
143.
The aim of the present observational study was to identify and characterize matrix metalloproteinase (MMP) -2, -8, -9, and -13 in gingival crevicular fluid (GCF) of patients with short root anomaly (SRA). GCF samples collected from affected maxillary central incisors and premolars of five SRA patients and five systemically and periodontally healthy controls were analysed using the zymographic technique for gelatinase A and B (MMP-2 and -9) and by Western blot for collagenase -2 and -3 (MMP-8 and -13). SRA GCF revealed MMP-9 (30 per cent of the total gelatinolytic activity), of which 18 per cent was in 90 kDa proform and 12 per cent in 71-82 kDa active form. Moreover, high-molecular weight complexes (37 per cent) and low-molecular size fragmented (33 per cent) gelatinolytic enzymes were detectable. No MMP-8 or -13 immunoreactivities existed. These results may suggest that activation and complex formation of MMP-9 is characteristic of SRA GCF. From the findings it may be assumed that the GCF of SRA teeth has low collagenolytic resorptive or pathological activity.  相似文献   
144.
Reports relating meat intake to prostate cancer risk are inconsistent. Associations between these dietary factors and prostate cancer were examined in a consortium of 15 cohort studies. During follow‐up, 52,683 incident prostate cancer cases, including 4,924 advanced cases, were identified among 842,149 men. Cox proportional hazard models were used to calculate study‐specific relative risks (RR) and then pooled using random effects models. Results do not support a substantial effect of total red, unprocessed red and processed meat for all prostate cancer outcomes, except for a modest positive association for tumors identified as advanced stage at diagnosis (advanced(r)). For seafood, no substantial effect was observed for prostate cancer regardless of stage or grade. Poultry intake was inversely associated with risk of advanced and fatal cancers (pooled multivariable RR [MVRR], 95% confidence interval, comparing ≥45 vs. <5 g/day: advanced 0.83, 0.70–0.99; trend test p value 0.29), fatal, 0.69, 0.59–0.82, trend test p value 0.16). Participants who ate ≥25 versus <5 g/day of eggs (1 egg ~ 50 g) had a significant 14% increased risk of advanced and fatal cancers (advanced 1.14, 1.01–1.28, trend test p value 0.01; fatal 1.14, 1.00–1.30, trend test p value 0.01). When associations were analyzed separately by geographical region (North America vs. other continents), positive associations between unprocessed red meat and egg intake, and inverse associations between poultry intake and advanced, advanced(r) and fatal cancers were limited to North American studies. However, differences were only statistically significant for eggs. Observed differences in associations by geographical region warrant further investigation.  相似文献   
145.
Shedded neuronal ICAM-5 suppresses T-cell activation   总被引:3,自引:0,他引:3       下载免费PDF全文
Intercellular adhesion molecules (ICAMs) bind to leukocyte β2 integrins, which, among other functions, provide costimulatory signals for T-cell activation. ICAM-5 (telencephalin) is expressed in the somadendritic region of neurons of the mammalian brain. The receptor for ICAM-5 is the integrin LFA-1, a major leukocyte integ-rin expressed in lymphocytes and microglia. In conditions of brain ischemia, epilepsy, and encephalitis, the soluble form of ICAM-5 (sICAM-5) has been detected in physiologic fluids. Here, we report that sICAM-5 attenuates the T-cell receptor-mediated activation of T cells as demonstrated by the decreased expression of the activation markers CD69, CD40L, and CD25 (IL-2R). This effect is most clearly seen in CD45ROLow (naive), and not in CD45ROHigh (memory) T cells, and is most effective early in priming, but not in the presence of strong costimulatory signals. Furthermore, sICAM-5 promotes the mRNA expression of the cytokines TGF-β1 and IFN-, but not TNF. The formation of sICAM-5 is promoted by activated T cells through the cleavage of ICAM-5 from neurons. This suggests that ICAM-5 is involved in immune privilege of the brain and acts as an anti-inflammatory agent.  相似文献   
146.
Sindbis virus (SINV) emerges as large human outbreaks in northern Europe every 7 years. Similar to many other alphaviruses, SINV is a mosquito-borne causative agent of a rash-arthritis. Previous reports suggest that in many alphavirus infections joint symptoms might persist for years. A prospective cohort of 49 patients was physically examined 3 y after verified acute SINV infection to reveal persistent joint symptoms. We carefully searched for a temporal association between the infection and current symptoms, and took into account other medical conditions. Sera were collected and analysed with enzyme immunoassays. Arthritis (swelling and tenderness on physical examination) was diagnosed in 4.1% (2/49) of the patients. Tenderness on palpation or in movement of a joint was found in 14.3% of the patients in the rheumatological examination, and an additional 10.2% complained of persisting arthralgia at the interview. Thus, 24.5% of the patients had joint manifestations attributable to the infection 3 y earlier. A positive IgM antibody response persisted in 3/49 of the patients; both patients with arthritis were in this group. As one-quarter of the patients were symptomatic 3 y after infection, it seems that persistent symptoms of SINV infection have considerable public health implications in areas with high seroprevalence.  相似文献   
147.
Different host genetic factors causes imbalance in the immune response. The purpose of this study was to establish whether pathological findings in chest radiography are related to the various host-related immunological factors in nephropathia epidemica (NE). Chest radiography findings, human leukocyte antigen (HLA) alleles B8, DR3, B27, genotypes of the genes of tumour necrosis factor alpha (TNFalpha), interleukin -1alpha (IL-1alpha), IL1beta and IL-1 receptor antagonist (IL1RA) were analysed in 114 patients with serologically confirmed acute NE. Both the presence and severity of abnormal NE-related chest radiography findings associated with the B8, DR3 and TNF2 alleles are known to form a frequent extended HLA haplotype in European populations. Pleural effusion showed the strongest association with these genetic factors. Pathological findings in chest radiography are related to host genetic factors in NE. Pleural effusion is a sign of increased capillary permeability, an important feature in NE. Host genetic factors may contribute to increased capillary permeability observed in NE patients.  相似文献   
148.
149.
150.
 The purpose of the study was to investigate pre-translational regulation of collagen expression after a single bout of exercise. We analysed steady-state messenger ribonucleic acid (mRNA) levels for collagen types I, III and IV, α- and β-subunits of prolyl 4-hydroxylase and lysyl oxidase (enzymes modifying procollagen chains), and enzyme activity of prolyl 4-hydroxylase from rat soleus muscle (MS) and the red parts of quadriceps femoris muscle (MQF) after 12 h and after 1, 2, 4, 7 and 14 days of downhill (–13.5°) treadmill running at a speed of 17 m·min–1 for 130 min. Histological and biochemical assays revealed exercise-induced muscle damage in MQF but not MS. Steady-state mRNA levels for the α- and β-subunits of prolyl 4-hydroxylase in MQF, lysyl oxidase in MS and MQF were increased 12 h after running, whereas prolyl 4-hydroxylase activity did not increase until 2 days after exercise. The mRNA levels for the fibrillar collagens (I and III) and basement membrane type IV collagen significantly increased 1 day and 12 h after exertion, respectively. Peak mRNA levels were observed 2–4 days after running, the increases being more pronounced in MQF than in MS. No significant changes were observed in types I or III collagen at the protein level. Strenuous downhill running thus causes an increase in gene expression for collagen types I and III and their post-translational modifying enzymes in skeletal muscle in a co-ordinated manner. These changes, together with the increased gene expression of type IV collagen, may represent the regenerative response of muscle extracellular matrix to exercise-induced injury and an adaptive response to running exertion. Received: 20 July 1998 / Received after revision: 30 November 1998 / Accepted: 26 January 1999  相似文献   
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