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221.
BackgroundWeb queries are now widely used for modeling, nowcasting and forecasting influenza-like illness (ILI). However, given that ILI attack rates vary significantly across ages, in terms of both magnitude and timing, little is known about whether the association between ILI morbidity and ILI-related queries is comparable across different age-groups. The present study aimed to investigate features of the association between ILI morbidity and ILI-related query volume from the perspective of age.MethodsSince Google Flu Trends is unavailable in Italy, Google Trends was used to identify entry terms that correlated highly with official ILI surveillance data. All-age and age-class-specific modeling was performed by means of linear models with generalized least-square estimation. Hold-out validation was used to quantify prediction accuracy. For purposes of comparison, predictions generated by exponential smoothing were computed.ResultsFive search terms showed high correlation coefficients of > .6. In comparison with exponential smoothing, the all-age query-based model correctly predicted the peak time and yielded a higher correlation coefficient with observed ILI morbidity (.978 vs. .929). However, query-based prediction of ILI morbidity was associated with a greater error. Age-class-specific query-based models varied significantly in terms of prediction accuracy. In the 0–4 and 25–44-year age-groups, these did well and outperformed exponential smoothing predictions; in the 15–24 and ≥ 65-year age-classes, however, the query-based models were inaccurate and highly overestimated peak height. In all but one age-class, peak timing predicted by the query-based models coincided with observed timing.ConclusionsThe accuracy of web query-based models in predicting ILI morbidity rates could differ among ages. Greater age-specific detail may be useful in flu query-based studies in order to account for age-specific features of the epidemiology of ILI.  相似文献   
222.
In liver the mitochondrial sirtuin, SIRT5, controls ammonia detoxification by regulating CPS1, the first enzyme of the urea cycle. However, while SIRT5 is ubiquitously expressed, urea cycle and CPS1 are only present in the liver and, to a minor extent, in the kidney. To address the possibility that SIRT5 is involved in ammonia production also in nonliver cells, clones of human breast cancer cell lines MDA-MB-231 and mouse myoblast C2C12, overexpressing or silenced for SIRT5 were produced. Our results show that ammonia production increased in SIRT5-silenced and decreased in SIRT5-overexpressing cells. We also obtained the same ammonia increase when using a new specific inhibitor of SIRT5 called MC3482. SIRT5 regulates ammonia production by controlling glutamine metabolism. In fact, in the mitochondria, glutamine is transformed in glutamate by the enzyme glutaminase, a reaction producing ammonia. We found that SIRT5 and glutaminase coimmunoprecipitated and that SIRT5 inhibition resulted in an increased succinylation of glutaminase. We next determined that autophagy and mitophagy were increased by ammonia by measuring autophagic proteolysis of long-lived proteins, increase of autophagy markers MAP1LC3B, GABARAP, and GABARAPL2, mitophagy markers BNIP3 and the PINK1-PARK2 system as well as mitochondrial morphology and dynamics. We observed that autophagy and mitophagy increased in SIRT5-silenced cells and in WT cells treated with MC3482 and decreased in SIRT5-overexpressing cells. Moreover, glutaminase inhibition or glutamine withdrawal completely prevented autophagy. In conclusion we propose that the role of SIRT5 in nonliver cells is to regulate ammonia production and ammonia-induced autophagy by regulating glutamine metabolism.  相似文献   
223.
The plant hormone abscisic acid (ABA) is present and active in humans, regulating glucose homeostasis. In normal glucose tolerant (NGT) human subjects, plasma ABA (ABAp) increases 5-fold after an oral glucose load. The aim of this study was to assess the effect of an oral glucose load on ABAp in type 2 diabetes (T2D) subjects. We chose two sub-groups of patients who underwent an oral glucose load for diagnostic purposes: i) 9 treatment-naive T2D subjects, and ii) 9 pregnant women with gestational diabetes (GDM), who underwent the glucose load before and 8–12 weeks after childbirth. Each group was compared with matched NGT controls. The increase of ABAp in response to glucose was found to be abrogated in T2D patients compared to NGT controls. A similar result was observed in the women with GDM compared to pregnant NGT controls; 8–12 weeks after childbirth, however, fasting ABAp and ABAp response to glucose were restored to normal in the GDM subjects, along with glucose tolerance. We also retrospectively compared fasting ABAp before and after bilio-pancreatic diversion (BPD) in obese, but not diabetic subjects, and in obese T2D patients, in which BPD resulted in the resolution of diabetes. Compared to pre-BPD values, basal ABAp significantly increased 1 month after BPD in T2D as well as in NGT subjects, in parallel with a reduction of fasting plasma glucose. These results indicate an impaired hyperglycemia-induced ABAp increase in T2D and in GDM and suggest a beneficial effect of elevated ABAp on glycemic control.  相似文献   
224.

Background

Epidemiological studies have suggested a possible role of trace elements (TE) in the etiology of several neurological diseases including Multiple Sclerosis (MS). Hair analysis provides an easy tool to quantify TE in human subjects, including patients with neurodegenerative diseases.

Objective

To compare TE levels in scalp hair from patients with MS and healthy controls from the same geographic area (Sicily).

Methods

ICP-MS was used to determine the concentrations of 21 elements (Ag, Al, As, Ba, Cd, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Pb, Rb, Sb, Se, Sr, U, V and Zn) in scalp hair of 48 patients with relapsing–remitting Multiple Sclerosis compared with 51 healthy controls.

Results

MS patients showed a significantly lower hair concentration of aluminum and rubidium (median values: Al = 3.76 μg/g vs. 4.49 μg/g and Rb = 0.007 μg/g vs. 0.01 μg/g;) and higher hair concentration of U (median values U: 0.014 μg/g vs. 0.007 μg/g) compared to healthy controls. The percentages of MS patients showing hair elemental concentrations greater than the 95th percentile of controls were 20% for Ni, 19% for Ba and U, and 15% for Ag, Mo and Se. Conversely, the percentages of MS patients showing hair elemental concentrations lower than the 5th percentile of healthy controls were 27% for Al, 25% for Rb, 22% for Ag, 19% for Fe, and 16% for Pb. No significant association was found between levels of each TE and age, disease duration or Expanded Disability Status Scale (EDSS) score. After stratification by gender, healthy subjects did not show any significant difference in trace element levels, while MS patients showed significant differences (p<0.01) for the concentrations of Ag, Cr, Fe, Ni and Sr. No significant differences were also found, at p<0.01, in relation to the use of cigarettes, consume of water, vegetables and place of living.

Conclusion

The different distributions of TE in hair of MS patients compared to controls provides an additional indirect evidence of metabolic imbalance of chemical elements in the pathogenesis of this disease. The increase in U and decrease in Al and Rb levels in MS compared to controls require further assessments as well as the observed different distributions of other elements.  相似文献   
225.

Purpose

aim of this study was to identify outcomes in pain relief and quality of life in patients with a solitary painful osseous metastasis treated by radiotherapy, cryoablation or the combination using a propensity score matching study design.

Materials and Methods

175 patients with painful bone metastases were included in the study. Twenty-five of them underwent a radiation course (20 Gy in five daily fractions) 15 days after the cryoablation. These subjects were retrospectively matched by propensity analysis with a group of subjects treated by radiotherapy (125 subjects) and with a group treated byCryoablation (25 subjects). The pain relief in terms of complete response, rate of subjects requiring analgesics after treatments and the changes in self-rated quality of life were measured. Informed consent was obtained from the subject and the study was approved by the local Ethical Committee.

Results

An higher proportion of subjects treated by cryoablation (32%) or cryoablation followed by RT (72%;) experienced a complete response compared with patients treated by radiotherapy alone (11.2%). After Bonferroni correction strategy, the addition of radiotherapy to cryoablation significantly improved the rate of complete response compared with cryoablation alone (p = 0.011) and this paralleled with an improved self-rated quality of life. Seventeen subjects (13.6%) of patients in the radiotherapy group, 9 (36%) in the cryoablation group, and 19 (76)% in the cryoablation- radiotherapy group did not require narcotic medications.

Conclusions

The addition of radiotherapy to cryoablation favorably impacts on perceived pain, with a favorable toxicity profile. However, our data should be interpreted with caution and could serve as a framework around which to design future trials.  相似文献   
226.
227.

Background

Celiac disease (CD) has a strong genetic component mainly due to HLA DQ2/DQ8 encoding genes. However, a minority of CD patients are DQ2/DQ8-negative. To address this issue, we retrospectively characterized HLA haplotypes in 5,535 subjects at risk of CD (either relatives of CD patients or subjects with CD-like symptoms) referred to our center during a 10-year period.

Methods

We identified loci DQA1/DQB1/DRB1 by sequence-specific oligonucleotide-PCR and sequence-specific primer-PCR; anti-transglutaminase IgA/IgG and anti-endomysium IgA by ELISA and indirect immunofluorescence, respectively.

Results

We diagnosed CD in 666/5,535 individuals, 4.2% of whom were DQ2/DQ8-negative. Interestingly, DQ7 was one of the most abundant haplotypes in all CD patients and significantly more frequent in DQ2/DQ8-negative (38%) than in DQ2/DQ8-positive CD patients (24%) (p<0.05).

Conclusion

Our data lend support to the concept that DQ7 represents an additive or independent CD risk haplotype with respect to DQ2/DQ8 haplotypes but this finding should be verified in other large CD populations.  相似文献   
228.

Background & Aims

Sleep disturbance is associated with the development of obesity, diabetes and hepatic steatosis in murine models. Hepatic triglyceride accumulation oscillates in a circadian rhythm regulated by clock genes, light-dark cycle and feeding time in mice. The role of the sleep-wake cycle in the pathogenesis of human non-alcoholic fatty liver disease (NAFLD) is indeterminate. We sought to detail sleep characteristics, daytime sleepiness and meal times in relation to disease severity in patients with NAFLD.

Methods

Basic Sleep duration and latency, daytime sleepiness (Epworth sleepiness scale), Pittsburgh sleep quality index, positive and negative affect scale, Munich Chronotype Questionnaire and an eating habit questionnaire were assessed in 46 patients with biopsy-proven NAFLD and 22 healthy controls, and correlated with biochemical and histological parameters.

Results

In NAFLD compared to healthy controls, time to fall asleep was vastly prolonged (26.9 vs. 9.8 min., p = 0.0176) and sleep duration was shortened (6.3 vs. 7.2 hours, p = 0.0149). Sleep quality was poor (Pittsburgh sleep quality index 8.2 vs. 4.7, p = 0.0074) and correlated with changes in affect. Meal frequency was shifted towards night-times (p = 0.001). In NAFLD but not controls, daytime sleepiness significantly correlated with liver enzymes (ALAT [r = 0.44, p = 0.0029], ASAT [r = 0.46, p = 0.0017]) and insulin resistance (HOMA-IR [r = 0.5, p = 0.0009]) independent of cirrhosis. In patients with fibrosis, daytime sleepiness correlated with the degree of fibrosis (r = 0.364, p = 0.019).

Conclusions

In NAFLD sleep duration was shortened, sleep onset was delayed and sleep quality poor. Food-intake was shifted towards the night. Daytime sleepiness was positively linked to biochemical and histologic surrogates of disease severity. The data may indicate a role for sleep-wake cycle regulation and timing of food-intake in the pathogenesis of human NAFLD as suggested from murine models.  相似文献   
229.
The formation of protein aggregates is important in many fields of life science and technology. The morphological and mechanical properties of protein solutions depend upon the molecular conformation and thermodynamic and environmental conditions. Non-native or unfolded proteins may be kinetically trapped into irreversible aggregates and undergo precipitation or gelation. Here, we study the thermal aggregation of lysozyme in neutral solutions. We characterise the irreversible unfolding of lysozyme by differential scanning calorimetry. The structural properties of aggregates and their mechanisms of formation with the eventual gelation are studied at high temperature by spectroscopic, rheological and scattering techniques. The experiments show that irreversible micron-sized aggregates are organised into larger clusters according to a classical mechanism of diffusion and coagulation, which leads to a percolative transition at high concentrations. At a smaller length scale, optical and atomic force microscopy images reveal the existence of compact aggregates, which are the origin of the aggregation irreversibility.  相似文献   
230.
The aim of this study was to evaluate the effect of poly-ethylene-co-vinyl acetate (EVA) films incorporating different concentrations (0.1%, 0.5% and 1%) of nisin on the biofilm-forming ability of Listeria monocytogenes ATCC 7644, Staphylococcus aureus 815 and Staphylococcus epidermidis ATCC 35984. Nisin was incorporated into two grades of EVA (EVA14 and EVA28) in the melt during a common film-blowing operation. The efficacy of EVA/nisin films was evaluated by biofilm biomass measurements and Live/Dead staining in combination with fluorescence microscopy. In order to evaluate whether the nisin incorporation could modify the film surface properties, contact angle measurements and scanning electron microscopy were performed. The results revealed the efficacy of EVA14/nisin films in reducing biofilm formation on their surfaces with more evident effect for S. epidermidis than L. monocytogenes and S. aureus strains. In contrast, EVA28/nisin films showed unsatisfactory activity. Fluorescence microscopy confirmed poor biofilm formation on EVA14/nisin films, also characterised by the presence of dead cells. The data presented in this study offer new potential applications for developing strategies aimed to improve the effect of antimicrobial agents.  相似文献   
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