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1.
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   
2.
Amidines (guanidine, formamidine, and acetamidine) were introduced as substitutes for the cationic heads present in atropine, scopolamine, and corresponding quaternary derivatives. Amidine systems are intermediate in structure between tertiary amines and quaternary compounds, at least as regards ionization and electronic properties, but differ from the latter in shape (planar not tetrahedral). They have additional binding opportunities on account of their hydrogen-bond-forming capacity. The effect of the introduction of these cationic heads on the affinity for different muscarinic acetyl choline receptor (m-AcChR) subtypes was investigated in vitro, in binding displacement studies, and in functional tests on isolated organs. All new compounds (3a,b-5a,b) showed high affinity for the m-AcChR considered, comparable or slightly inferior to that of the parent drugs (1a-e). The new amidine derivatives proved effective as spasmolytic agents, with little tendency to cause central effects. However, no separation was achieved of spasmolytic and other untoward effects, like inhibition of salivation. Thus, amidine moieties are effective bioisosteric substitutes for conventional cationic heads present in antimuscarinic agents. Their unusual physical-chemical properties make them useful tools when modulation of pharmacokinetic or pharmacodynamic effects is required.  相似文献   
3.
Mifentidine, a representative compound of a novel class of H2-antagonists, has been investigated for its ability to interact with H2-receptors and to inhibit gastric acid secretion. Affinity estimates (K B) of mifentidine obtained fromin vitro studies on cardiac and gastric mucosal histamine (H2) receptors were in the 20–50 nM range. Mifentidine appeared to be endowed with strong antisecretory properties against histamine-stimulated secretion in the anaesthetized rat and in the conscious dog. Distinct features of mifentidine were considerable bioavailability and duration of anti-secretory effect.  相似文献   
4.
It has been hypothesized that bidentate hydrogen bonding plays an important role in the interaction of imidazolylphenylformamidines with the H2-receptor. The present study, in which the degree of pseudoirreversible H2-antagonism of the four isomeric butyl substituted mifentidine analogues was determined on the spontaneously beating right atrium of the male guinea-pig, lends further support to this hypothesis. In solution the EE/EZ ratio is different for the four isomeric butylated mifentidine analogues. The rank order of the percentage of E,E conformation, which favors a bidentate interaction, of the formamidine moiety parallels the rank order of pseudo-irreversible H2-antagonism.  相似文献   
5.
D,L-4-(3,4-Dichloro-benzoylamino)-5-(N-3-methoxypropyl- pentylamino)-5-oxo-pentanoic acid (CR 1505) belongs to a newly discovered class of agents with cholecystokinin (CCK) antagonistic activity. CR 1505 displaces CCK-8 from the central CCK receptors at concentrations of 9.1 mumol/l, and from the peripheral CCK receptors at concentrations of 0.33 mumol/l. CR 1505 antagonizes in vitro the contractant effects of CCK-8 on gall bladder strips of the guinea pig at 0.79 mumol/l and those on the small intestine at 1.6 mumol/l. These antagonistic effects are dose dependent and of competitive type. The antagonistic activities of CR 1505 against contractions of smooth muscles elicited by CCK-8 are at least 1000 times more potent than those against the contractions elicited by acetylcholine, BaCl2, histamine, serotonin, Substance P, bradykinin or dimethylphenylpiperazine. CR 1505 is also practically ineffective against the contractions of the small intestine of the guinea pig elicited by electrical field stimulations either as "cholinergic twich" (0.05 Hz), or as "cholinergic contractions" (trains of 10 min at 1 Hz), or as "non-cholinergic contractions" (200 impulses at 5 Hz in presence of atropine). CR 1505 is therefore a potent, specific, competitive and reversible CCK antagonist.  相似文献   
6.
The assessment of nutritional intakes during hospitalization is crucial, as it is known that nutritional status tends to worsen during the hospital stay, and this can lead to the negative consequences of malnutrition. International guidelines recommend the use of parenteral nutrition (PN) in hypophagic, non-surgical patients at nutritional risk, with contraindications to enteral nutrition. However, to date, there are no published data regarding either energy intake or objective measurements associated with it in this patient population. The aim of the present exploratory methodological study was to evaluate whether phase angle (PhA) and handgrip strength normalized for skeletal muscle mass (HG/SMM) are sensitive early markers of energy intake in hypophagic, non-surgical patients at nutritional risk, with contraindications to enteral nutrition. We evaluated 30 eligible patients, who were treated with personalized dietary modifications and supplemental PN for at least one week during hospitalization. In a liner regression model adjusted for age, gender, basal protein intake and the basal value of each variable, a trend toward improvement of PhA and preservation of HG/SMM was observed in patients satisfying the estimated calorie requirements (N = 20), while a significant deterioration of these parameters occurred in those who were not able to reach the target (N = 10). The mean adjusted difference and 95% CI were +1.4° (0.5–2.3) (p = 0.005) for PhA and +0.23 (0.20–0.43) (p = 0.033) for HG/SMM. A significant correlation between PhA and HG/SMM variations was also observed (r = 0.56 (95% CI, 0.23–0.77); p = 0.0023). PhA and HG/SMM were able to distinguish between hypophagic, non-surgical patients at nutritional risk who satisfied their estimated caloric requirements and those who did not after a one-week personalized nutritional support. Clinical studies are warranted, in order to verify these preliminary observations and to validate the role of PhA variations as early markers of anabolic/catabolic fluctuations.  相似文献   
7.
Metabolic Brain Disease - Aicardi-Goutières Syndrome (AGS) is a monogenic leukodystrophy with pediatric onset, clinically characterized by a variable degree of neurologic impairment. It...  相似文献   
8.
Recent studies suggest that Cu/Zn superoxide dismutase (SOD1) could be pathogenic in both familial and sporadic amyotrophic lateral sclerosis (ALS) through either inheritable or nonheritable modifications. The presence of a misfolded WT SOD1 in patients with sporadic ALS, along with the recently reported evidence that reducing SOD1 levels in astrocytes derived from sporadic patients inhibits astrocyte-mediated toxicity on motor neurons, suggest that WT SOD1 may acquire toxic properties similar to familial ALS-linked mutant SOD1, perhaps through posttranslational modifications. Using patients' lymphoblasts, we show here that indeed WT SOD1 is modified posttranslationally in sporadic ALS and is iper-oxidized (i.e., above baseline oxidation levels) in a subset of patients with bulbar onset. Derivatization analysis of oxidized carbonyl compounds performed on immunoprecipitated SOD1 identified an iper-oxidized SOD1 that recapitulates mutant SOD1-like properties and damages mitochondria by forming a toxic complex with mitochondrial Bcl-2. This study conclusively demonstrates the existence of an iper-oxidized SOD1 with toxic properties in patient-derived cells and identifies a common SOD1-dependent toxicity between mutant SOD1-linked familial ALS and a subset of sporadic ALS, providing an opportunity to develop biomarkers to subclassify ALS and devise SOD1-based therapies that go beyond the small group of patients with mutant SOD1.  相似文献   
9.
BackgroundLiterature suggests that sex steroid hormones may modify the risk for Parkinson's disease (PD). We investigated the potential effect of reproductive factors on the clinical features of idiopathic PD (IPD) patients.MethodsAll IPD female patients admitted to and evaluated at our Institute over a 12-month period were included in the present cross-sectional study. We investigated the effect of the following parameters by multivariate linear regression analysis: age at menarche, age at menopause, length of fertile life, duration of exposure to endogenous estrogens and cumulative length of pregnancies, use of contraceptives and hormonal replacement therapy.ResultsIn total, 579 patients were evaluated and 497 reported menopause before PD onset. In this population, age at PD onset was positively associated with age at menarche and at menopause, length of fertile life and duration of estrogen exposure. Moreover, UPDRS motor score was inversely associated with age at menopause, length of fertile life and duration of estrogen exposure. Increasing age at menarche was also associated with predominant resting tremor at PD onset. In models refitted on patients with early PD (disease duration <5 years; N = 226) all the associations found were confirmed. The relationship between surrogates of estrogen exposure and UPDRS motor score actually became more significant.ConclusionsOur observations support the concept that hormonal exposure of the nigro-striatal network during life may influence its susceptibility to degenerative stimuli in later life, but the association does not seem to be unique? unidirectional. In particular, increased severity of PD signs correlates with shorter duration of estrogen exposure. The underlying mechanisms need to be clarified.  相似文献   
10.
Pancreatic cancer is one of the most deadly cancers and is characterized by a poor prognosis. Single agent gemcitabine, despite its limited activity and modest impact on disease outcome, is considered as the standard therapy in pancreatic cancer. Most of the combination regimens used in the treatment of this disease, also including the targeted agents, did not improve the outcome of patients. Also, taxanes have been tested as single agent and in combination chemotherapy, both in first line and as salvage chemotherapy, as another possible option for treating pancreatic cancer. The inclusion of taxanes in combination with gemcitabine as upfront therapy obtained promising results. Accordingly, taxanes, and above all, new generation taxanes, appear to be suitable candidates for further testing to assess their role against pancreatic cancer in various clinical settings.  相似文献   
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