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91.
92.
Potassium canrenoate (PC), a competitive aldosterone antagonist previously found to increase tumor incidence in rats and to produce genotoxic effects in in vitro systems, was examined in rats to acquire information on its genotoxic activity in vivo. Intragastric administration of 1/2 LD50 produced, as revealed by the Comet assay, a modest but statistically significant increase in the frequency of DNA lesions in liver but not in thyroid and bone marrow of male rats, and in thyroid and bone marrow but not in liver of female rats. In contrast with the frankly positive responses observed in primary cultures of rat hepatocytes (Martelli et al., Mutagenesis 14 (1999) 463-472) any evidence of DNA repair and micronuclei formation was absent in liver of rats treated with 1/2 LD50, and initiation of enzyme-altered liver preneoplastic lesions did not occur in the liver of rats given 100 mg/kg PC once a week for 6 successive weeks. A high and dose-dependent frequency of DNA lesions was found to occur in testes and ovaries of rats given single doses ranging from 1/8 to 1/2 LD50.  相似文献   
93.
Providing assistance services for sexual activity is becoming of increasing importance to the community of people with disabilities and to mental health professionals. Nevertheless, the literature on this topic is sparse. The aim of this study is to explore potential clients’ and assistants’ views, needs, experiences, opinions, and concerns about sexual assistance (SA) in Italy. Twenty-two semi-structured interviews were conducted with 12 people with a congenital physical disability and 10 would-be assistants. A Grounded Theory approach was used to analyze data. Participants with disabilities considered SA useful. Despite most of them having unfulfilled sexual needs, they would prefer to have their sexual needs met within a romantic relationship. Would-be assistants constructed themselves as people who have a “natural aptitude to being useful”. Results suggest that SA services might represent an opportunity for people with disabilities to discover new ways to satisfy their personal needs and to live more autonomously while, at the same time, allowing would-be sexual assistants to fulfill their desire to be helpful. Nevertheless, the use of SA is likely to only be a part of the answer to fulfilling the sexual needs of people with disabilities.  相似文献   
94.
Context: Solid lipid nanoparticles (SLN) are drug carriers possessing numerous features useful for topical application. A copious scientific literature outlined their ability as potential delivery systems for lipophilic drugs, while the entrapment of a hydrophilic drug inside the hydrophobic matrix of SLN is often difficult to obtain.

Objective: To develop SLN intended for loading caffeine (SLN-CAF) and to evaluate the permeation profile of this substance through the skin once released from the lipid nanocarriers. Caffeine is an interesting compound showing anticancer and protective effects upon topical administration, although its penetration through the skin is compromised by its hydrophilicity.

Materials and methods: SLN-CAF were formulated by using a modification of the quasi-emulsion solvent diffusion technique (QESD) and characterized by PCS and DSC analyses. In vitro percutaneous absorption studies were effected using excised human skin membranes (i.e. Stratum Corneum Epidermis or SCE).

Results: SLN-CAF were in a nanometric range (182.6?±?8.4?nm) and showed an interesting payload value (75%?±?1.1). DSC studies suggest the presence of a well-defined system and the successful drug incorporation. Furthermore, SLN-CAF generated a significantly faster permeation than a control formulation over 24?h of monitoring.

Discussion and conclusions: SLN-CAF were characterized by valid dimensions and a good encapsulation efficiency, although the active to incorporate showed a hydrophilic character. This result confirms the suitability of the formulation strategy employed in the present work. Furthermore, the in vitro evidence outline the key role of lipid nanoparticles in enhancing caffeine permeation through the skin.  相似文献   
95.
BACKGROUND: The purpose of this study was to identify the optimal measures for diagnosing iron deficiency (ID) in oral contraceptive (OC) users and nonusers, and to estimate ID frequency in relation to OC use. STUDY DESIGN: Conventional biomarkers of iron status - serum ferritin, iron, transferrin (Tf) and transferrin saturation (TfS) - were compared with serum soluble Tf receptor (sTfR) and the sTfR/log ferritin ratio (sTfR-F index). Two hundred two healthy menstruating white Italian women (aged 24+/-4.8 years) were analyzed. Serum ferritin concentrations <12 microg/L were considered as ID. RESULTS: ID was detected in 29.7% (60/202) of the study women. Fifty-nine women were OC users (59/202, 29.2%). OC use did not significantly affect ID prevalence (p=.24). However, OC use markedly increased Tf in OC users, who had an odds ratio (OR) of 9.3 (CI 3.8-22.7, p<.001) for elevated Tf >330 mg/dL. No other iron status measure was affected by OC. Of the markers for ID adjunctive to ferritin, an elevated sTfR-F index >or =1.5 showed the best performance. Specifically in OC users, the elevated sTfR-F index had better sensitivity (81.0% vs. 33.3%), specificity (94.7% vs. 92.1%), efficiency (89.8% vs. 71.2%), positive predictive value (89.5% vs. 70.0%) and negative predictive value (90.0% vs. 71.1%) than a TfS <15%. Additionally, the sTfR-F index allowed the identification of low iron stores in 4.5% (9/202) of women with ferritin > or =12 microg/L. CONCLUSION: Among healthy OC users and non-OC users, the sTfR-F index had the highest performance for diagnosing ID compared with other serum markers adjunctive to ferritin measurements, whereas sTfR by itself had a low sensitivity. We showed that neither the sTfR nor sTfR-F index was affected by third-generation OC use. The sTfR measurement is useful in the diagnosis of ID, especially in women using OC, where Tf and TfS tests may be misleading.  相似文献   
96.
The relation between coffee intake and risk of amyotrophic lateral sclerosis (ALS) was investigated in 377 newly diagnosed ALS patients from 4 Italian population-based registries in the European ALS Consortium (EURALS Group) (2007-2010). For each patient, 2 age- and sex-matched hospital controls were selected, one from a neurology department and one from a nonneurologic department. Two additional healthy control groups were identified from local general practitioners' (GPs') lists (n = 99) and residents of the same area as a cancer cohort (n = 7,057). Coffee intake was defined in terms of status (ever consuming coffee daily for ≥6 months vs. never), duration, and history (never, former, or current). Ever coffee drinkers comprised 74.7% of ALS patients, 80.4% of neurologic controls, 85.6% of nonneurologic controls (P = 0.0004), 88.9% of GP controls (P = 0.0038), and 86.0% of cancer cohort controls (P < 0.0001). Current coffee drinkers comprised 60.2% of ALS patients, 70.2% of neurologic controls (P = 0.0294), 76.4% of nonneurologic controls (P < 0.0001), and 82.3% of GP controls (P = 0.0002); duration of intake was ≥30 years for 62.3%, 67.7%, 74.7%, and 72.6%. ALS patients had lower lifetime coffee exposure: Odds ratios were 0.7 (95% confidence interval (CI): 0.5, 1.1), 0.6 (95% CI: 0.4, 0.8), and 0.4 (95% CI: 0.2, 0.9) in comparison with neurologic, nonneurologic, and GP controls, respectively. In current (vs. never) coffee drinkers, odds ratios were 0.7 (95% CI: 0.5, 1.0), 0.5 (95% CI: 0.3, 0.7), and 0.4 (95% CI: 0.2, 0.8), respectively. These findings provide epidemiologic evidence of an inverse correlation between coffee intake and ALS risk.  相似文献   
97.
Advanced Merkel cell carcinoma (MCC) is a very aggressive, rare neuroendocrine tumor of the skin with a high frequency of locoregional recurrence and metastasis, and a high mortality rate. Surgical resection, sentinel lymph node biopsy, and radiotherapy represent the gold standard of treatment in patients with localized disease, while chemotherapy has a significant role in the treatment of advanced disease. However, no definitive evidence on the survival impact of radiotherapy in the advanced stages has been provided to date, and response to chemotherapy remains brief in the majority of cases, indicating an urgent need for alternative approaches. Biological and genome sequencing studies have implicated multiple molecular pathways in MCC, thus leading to the development of new agents that target angiogenic factors, anti-apoptosis molecules, poly-ADP ribose polymerase, intracellular signal proteins such as the PI3K/AKT/mTOR pathway, and peptide receptors such as somatostatin receptors. More recently, immunotherapy agents such as avelumab, pembrolizumab, and nivolumab, which act by blocking the programmed cell-death (PD)-1/PD-L1 immune checkpoint, have shown promising results, especially in the advanced setting, and should now be considered standard of care for metastatic MCC. Current research is focusing on developing new immunotherapeutic strategies, identifying predictive biomarker to aid in the selection of patients responsive to immunotherapy, and defining combination approaches to increase efficacy in refractory patients.  相似文献   
98.
Ultra-hypofractionated radiotherapy (RT) is given over a shorter time with larger doses with respect to conventional fractionation in patients with localized prostate cancer (PCa). The use of hypofractionation is supported both from the radiobiological point of view (the low α/β-ratio in PCa and dose escalation) and from the rising number of clinical evidences. The aim of this study is to review our data regarding oncological outcomes, namely biochemical progression-free survival (b-PFS) and clinical progression-free survival (c-PFS), acute and long-term toxicities in patients treated with a ultra-hypofractionated RT. A series of 194 patients with clinically localized PCa treated primarily with ultra-hypofractionated RT using image-guided intensity modulated RT (IG-IMRT) at our Institute from 2012 to 2015 was included in this analysis. According to NCCN risk group classification, 65 (33.5%) patients were low risk, 101 (52.1%) intermediate risk, and 28 (14.4%) high risk. Androgen deprivation therapy (ADT) was given to 61 patients (31.4%). A 169 patients (87.1%) received 35 Gy in 5 fractions, while 25 patients (13%) received 32.5 Gy in 5 fractions (usually given in patients with comorbidity). The median duration of the treatment was 10 days (IQR 9–12). Biochemical relapse was defined as a rise of prostate specific antigen (PSA)?>?2 ng/ml above nadir. b-PFS, c-PFS, and freedom from gastro-intestinal (GI) and genito-urinary (GU) toxicity curves were calculated by the Kaplan–Meier method. Log-rank test and multivariate Cox models were used to investigate the role RT dose and heterogeneity by NCCN risk groups adjusting for prognostic factors. Data on acute and late term toxicities were collected according to RTOG/EORTC grading system. With a median follow-up of 30?months, 17 patients experienced PSA failure (9%). The 3-year b-PFS was 87% for all patients and rates stratified for the NCCN risk were 94, 82, and 66% for low-, intermediate-, and high-risk groups, respectively. Log-rank tests indicate that biochemical progression was significantly greater for patients with initial PSA (iPSA) greater than 7 ng/ml (P?=?0.04), high- and intermediate-risk groups (P?=?0.002), low total dose (P?=?0.02) and Gleason score (GS) equal or greater than 7 (P?=?0.04). No statistically significant association was found with T stage nor ADT. In multivariate analyses, total dose (P?=?0.03) and risk groups (P?=?0.03) remained significantly associated with recurrence. Acute and late GI and GU toxicity were acceptable. The toxicity of ultra-hypofractionated IG-IMRT in a large clinical cohort of PCa patients was tolerable and confirmed that this treatment is safe and offers excellent tumor control. Moreover, the hypofractionated RT allows to deliver the whole RT over 10 days with a sensible impact in patients’ quality of life and potential overall health system and social benefits.  相似文献   
99.
A soluble form of human low-density lipoprotein receptor (LDL-R) fused in frame with rabbit transferrin (LDL-Rs(hu)/Tf(rab)) is assessed in vivo as a therapeutic tool for lowering plasma LDL cholesterol. The cDNA encoding LDL-Rs(hu)/Tf(rab) is expressed in mice, using a hydrodynamics-based gene transfer procedure. The transgene is transcribed in the liver of transduced animals and the corresponding protein is secreted into the bloodstream. Circulating LDL-Rs(hu)/Tf(rab) binds LDL specifically, thus indicating that it is correctly processed through the cellular compartments in vivo. More importantly, the expression of LDL-Rs(hu)/Tf(rab) allows the removal of injected human (125)I-labeled LDL ((123)I-LDL) from the bloodstream of transduced CD1 mice, which show faster LDL plasma clearance, anticipating by approximately 90 min the same clearance value observed in control animals. A similar effect is observed in transduced LDL-R(-/-) mice, in which the clearance of injected human LDL depends solely on the presence of circulating LDL-Rs(hu) /Tf(rab). In these animals the extent of plasma LDL clearance is directly related to the concentration of LDL-Rs(hu)/Tf(rab) in the blood. Finally, LDL-Rs(hu)/Tf(rab) does not alter the pattern of LDL organ distribution: in transduced animals, as well as in control animals, liver and bladder are the predominantly labeled organs after (123)I-LDL injection. However, LDL-Rs(hu)/Tf(rab) has a quantitative effect on LDL tissue deposition: in treated animals LDL-Rs(hu)/Tf(rab) determines an increase in radioactivity in the liver at early times after (123)I-LDL injection and a progressive labeling of the bladder, starting 20 min after injection.  相似文献   
100.
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