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The purpose of the work was to set‐up a simple method to evaluate the contribution of Mn2+ ions in the intra‐ and extracellular tumor compartments in a MEMRI experiment. This task has been tackled by “silencing” the relaxation enhancement arising from Mn2+ ions in the extracellular space. In vitro relaxometric measurements allowed assessment of the sequestering activity of DO2A (1,4,7,10‐tetraazacyclododecane‐1,7‐diacetic acid) towards Mn2+ ions, as the addition of Ca‐DO2A to a solution of MnCl2 causes a drop of relaxivity upon the formation of the highly stable and low‐relaxivity Mn‐DO2A. It has been proved that the sequestering ability of DO2A towards Mn2+ ions is also fully effective in the presence of serum albumin. Moreover, it has been shown that Mn‐DO2A does not enter cell membranes, nor does the presence of Ca‐DO2A in the extracellular space prompt migration of Mn ions from the intracellular compartment. On this basis the in vivo, instantaneous, drop in SE% (percent signal enhancement) in T1‐weighted images is taken as evidence of the sequestration of extracellular Mn2+ ions upon addition of Ca‐DO2A. By applying the method to B16F10 tumor bearing mice, T1 decrease is readily detected in the tumor region, whereas a negligible change in SE% is observed in kidneys, liver and muscle. The relaxometric MRI results have been validated by ICP‐MS measurements. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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Aim and methods  Nutrition, unhealthy lifestyles and cancer appear to be strictly related, but few authors have analysed the interest in dietary information of cancer patients and their families. This survey was conducted in the Veneto area (Italy) to investigate the concern of cancer patients and their family members about diet as a health tool before and after diagnosis of cancer. Results  Seven hundred and four questionnaires were collected: 380 from cancer patients and 324 from family members of cancer subjects. Breast cancer (BC) was the most frequent disease for patients (61.8%) as well as families (26.5%). Generally, the importance of having precise diet information after diagnosis is recognised by 40.3% of patients, with significant differences between the various types of cancer: gastric and colon/rectum cancer (GCC) patients were more concerned than BC women about precise information concerning a diet to follow immediately after diagnosis (p = 0.000, ODs = 3.10, CI 1.68–5.71) or during treatments (p = 0.001, ODs = 2.67, CI 1.46–4.89). The nutritional information is supplied to patients in 34% of cases and to relatives in 30.3%, often from non-medical sources. In total healthcare workers (family doctor, oncologist, surgeon, dietician) represented the exclusive source of dietary information for 24.9% of patients and 22.9% of family members. Diet after diagnosis changes in 69.1% of GCC patients and in 39.2% of BC women. Relatives, particularly women, report difficulties preparing patients’ meals in 30.7% of cases, changes in the eating habits of the entire family in 29.9% and discontent connected with patients diet in 13.9%. The concern about proper nutrition after diagnosis increases more in GCC subjects (p < 0.025) when compared to BC subjects and in patients with more recent diagnosis (p < 0.041) when compared with patients with diagnosis >5 years ago, while in family members the interest in diet after diagnosis increases more in women than in men (p < 0.030) without other differences regarding the degree of relationship, type of cancer or diagnosis time. Relatives (92.7%) have more interest in nutritional education than patients (74.9%). Cancer patients <65 years were more interested in educational initiatives concerning nutrition (p = 0.000, ODs = 4.46, CI 2.6–7.4) than older patients (>65 years) and female subjects were more concerned than male patients (p = 0.008, ODs = 2.11, CI 1.2–3.6). Conclusions  The interest in the dietary knowledge and in educational initiatives concerning nutrition is high in cancer patients and their relatives, although it decreases with the age. The poor attention paid to nutrition of cancer patients by various healthcare workers deserves consideration, since the psychophysical wellbeing and perhaps also survival of cancer patients can be improved by correct dietary management, as well as, naturally, by the principal treatments themselves.  相似文献   
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The occurrence of transitory cognitive impairment during diffuse subclinical electroencephalographic (EEG) discharges has been widely documented but the role of the parameters influencing the cognitive performance and the involvement of motor or verbal response in the tasks used is still under debate. Fifteen patients suffering from primary generalized epilepsy with frequent bisynchronous EEG epileptic bursts underwent a shape recognition task during EEG monitoring. The test sequence was as follows: memorandum, pause, and multiple choice set. After pressing the response button, the patient was asked to confirm the choice verbally. The following parameters were considered: geometrical complexity of the shape, chronological position of the burst occurring during the single test, and the duration of discharge ranging from 1 to 3 s. Results showed a significant increase in incorrect responses during the test when discharges occurred, with more errors occurring for difficult than for easy shapes. Neither the discharge position nor the duration of the epileptic burst influenced the performance. Diffuse epileptic activity of short duration produced selective effects on the cognitive process regardless of the motor component of the response.  相似文献   
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At present the pathogenesis of diabetic nephropathy remains unresolved. Clearly lack of insulin, with its associated disorders of carbohydrate, protein, and/or lipid metabolism, initiates the process which eventually leads to the characteristic histologic picture of diabetic nephropathy. The disturbance in cellular metabolism per se could directly injure the kidney by altering the energy needs of the cell or by leading to the accumulation of cellular toxins (ie, polyols) or by causing the deficiency of key cellular metabolites (ie, myoinositol). Elevation of the plasma glucose concentration enhances the glycosylation of proteins, which in turn can lead to glomerular basement membrane thickening, loss of charge selectivity, and direct cellular damage. The multiple disturbances in intermediary metabolism are associated with increased levels of and/or enhanced sensitivity to a variety of growth factors, including IGF-I and angiotensin, and this could lead to glomerular hypertrophy. An increase in the filtered load and subsequent reabsorption of electrolytes and metabolites also could contribute to renal hypertrophy. In all animal models of nephropathy, including diabetes, glomerular hypertrophy has been shown to be the best correlate of glomerular sclerosis, proteinuria, and progressive renal deterioration. The potential mechanisms by which glomerular hypertrophy can lead to renal histologic damage were discussed previously. By increasing the luminal diameter, glomerular hypertrophy also would be expected to augment wall tension and thereby increase intraglomerular pressure. Derangements in cellular metabolism or altered sensitivity to angiotensin also can directly elevate the intraglomerular pressure and lead to structural renal damage. In this schema, elevated intraglomerular pressure is but one of many pathogenic factors that contribute to the development of diabetic glomerulopathy and albuminuria. The precise role of increased glomerular pressure in the evolution of diabetic nephropathy remains uncertain at present. In rats, severe diabetic nephropathy can occur without an increase in Pgc, while in humans, hyperfiltration does not appear to be a predictor of proteinuria and renal dysfunction. Lastly, it is likely that a variety of other factors, including the coagulation system, plasma/cell lipid levels, prostaglandins, etc, also play a role in the pathogenesis of diabetic nephropathy. According to the outline presented in Figure 1, it is unlikely that any single factor will be sufficient to explain the development of diabetic glomerulosclerosis. Ultimately, the origin of diabetic nephropathy in IDDM must be traced to insulin lack, with its associated derangements in cellular metabolism. Therefore, the importance of tight glucose control should not be underemphasized.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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Ten protein coding loci (6‐PGD, A1‐AT, ACP1, CaII, ESD, GC, GPX1, Hbβ, PGM1, and TF) were analyzed in the Mbenzele Pygmies from the Central African Republic. The frequency data were used to calculate the genetic distances between Mbenzele Pygmies and other African groups. In the principal coordinate plot of FST genetic distances, the Mbenzele cluster together with other Pygmies of the western cluster, the Biaka from C.A.R., Gielli from Cameroon, and Babinga from Congo. By contrast, they are considerably distanced from other Pygmy groups of the eastern cluster (Twa from Rwanda, Mbuti from Zaire). Genetic distances obtained using protein loci were compared with those based on microsatellite loci. The two distance matrices are insignificantly correlated (r = 0.268; one tail probability = 0.332), and the main difference is in the higher genetic affinity between the Mbenzele and Biaka Pygmies observed at the protein level. Although reasons underlying the discrepancy between inter‐populational variation at protein and DNA loci are not established with certainty, the comparison suggests that the genetic distance between the Mbenzele and Biaka Pygmies at microsatellite loci could have been shaped by genetic drift. Am. J. Hum. Biol. 14:9–14, 2002.© 2002 Wiley‐Liss, Inc.  相似文献   
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