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This work focuses on the comparison between Newtonian and non-Newtonian blood flows through a bileaflet mechanical heart valve in the aortic root. The blood, in fact, is a concentrated suspension of cells, mainly red blood cells, in a Newtonian matrix, the plasma, and consequently its overall behavior is that of a non-Newtonian fluid owing to the action of the cells' membrane on the fluid part. The common practice, however, assumes the blood in large vessels as a Newtonian fluid since the shear rate is generally high and the effective viscosity becomes independent of the former. In this paper, we show that this is not always the case even in the aorta, the largest artery of the systemic circulation, owing to the pulsatile and transitional nature of the flow. Unexpectedly, for most of the pulsating cycle and in a large part of the fluid volume, the shear rate is smaller than the threshold level for the blood to display a constant effective viscosity and its shear thinning character might affect the system dynamics. A direct inspection of the various flow features has shown that the valve dynamics, the transvalvular pressure drop and the large-scale features of the flow are very similar for the Newtonian and non-Newtonian fluid models. On the other hand, the mechanical damage of the red blood cells (hemolysis), induced by the altered stress values in the flow, is larger for the non-Newtonian fluid model than for the Newtonian one. [ABSTRACT FROM AUTHOR]

Frailty is a condition of increased vulnerability to cope with stressors, predisposing to the development of disability in basic and instrumental activities of daily living, falling, institutionalization and finally death. It is characterized by the loss of functional reserve in multiple domains resulting in a reduced tolerance to common external stresses. The pathogenetic steps conducting to frailty are not completely clear, but there is increasing evidence of a crucial role of insulin resistance and systemic inflammation in the development of frailty, disability, and related medical conditions. These two conditions may act directly, through a negative impact on homeostatic regulation and cross-systems compensation, or indirectly, by the effect of several diseases strongly related to frailty. Therefore, counteracting insulin resistance and systemic inflammation could be a powerful way to prevent the development of frailty and/or of its adverse outcomes. In this framework, diet and physical exercise may represent two important weapons in the prevention of frailty; indeed, current literature supports the effectiveness of a correct lifestyle based on a healthy diet (Mediterranean type diet) and regular physical exercise on frailty primary prevention. Studies on secondary prevention of frailty suggest that multi-component and resistance training, together with adequate energy and protein intake, might be helpful although data are still lacking. The efficacy of dietary supplementation in secondary prevention of frailty, albeit promising, remains to be confirmed in large clinical trials. [ABSTRACT FROM AUTHOR]

Background: Preoperative chemoradiotherapy (CRT) improves the survival of patients with oesophageal cancer when compared with surgery alone.Methods: We conducted a phase II, multicenter trial of FOLFOX-4 and cetuximab in patients with locally advanced oesophageal cancer (LAEC) followed by daily radiotherapy (180 cGy fractions to 5040 cGy) with concurrent weekly cetuximab. Cytokines levels potentially related to cetuximab efficacy were assessed using multiplex-bead assays and enzyme-linked immunosorbent assay at baseline, at week 8 and at week 17. Primary end point was complete pathological response rate (pCR).Results: In all, 41 patients were enroled. Among 30 patients who underwent surgery, a pCR was observed in 8 patients corresponding to a rate of 27%. The most frequent grade 3/4 toxicity was skin (30%) and neutropenia (30%). The 36-month survival rates were 85 and 52% in patients with pathological CR or PR vs 38 and 33% in patients with SD or PD.Conclusions: Incorporating cetuximab into a preoperative regimen for LAEC is feasible; no correlation between cytokines changes and patient outcome was observed. Positron emission tomography/computed tomography study even if influenced by the small number of patients appears to be able to predict patients outcome both as early and late metabolic response. [ABSTRACT FROM AUTHOR]

Study design:Description of a technique and prospective follow-up study. Objectives:The aim of this study was to present our experience in the surgical treatment of ischial pressure sores, especially recurrence. Setting:The Department of Plastic and Reconstructive Surgery and Spinal Injuries Unit, CTO Hospital, Rome, Italy. Methods:From 1995 to 1997, the authors used in 12 consecutive paraplegic patients, who had a grade III or IV decubitus ulcer in the ischial area only, two different and independent flaps coupled together in a 'criss-cross' musculocutaneous flap: a split-muscle gluteus maximus flap and a rhomboid fasciocutaneous local flap. The average follow-up period was 3 years and 9 months. Details of the operative procedure are presented to prove that this criss-cross closure of the ischial pressure sore beneficial for patients with spinal cord injury. Results:All flaps survived; recurrence of the decubitus ulcer occurred in one patient (8%). Pressure-sore-free survival after surgery was 20 months in the patient with recurrence and an average of 26 months in patients without recurrence. Conclusion:The results obtained confirm this procedure to be safe and useful. We believe this technique to be a valuable alternative for the reconstruction of primary or recurrent ischial pressure ulcers. [ABSTRACT FROM AUTHOR]

The recent successful development of monoclonal antibodies that target key components of biological pathways has expanded the armamentarium of treatment options for patients with colorectal cancer (CRC). In particular, the epidermal growth factor receptor (EGFR), a tyrosine kinase growth factor receptor involved in CRC development and progression, is exploited by the newest monoclonal antibody that is available for use in CRC patients. Cetuximab, the first chimeric monoclonal antibody, which has been generated against the EGFR, is currently registered in USA, Europe and worldwide, in combination with irinotecan in the treatment of metastatic CRC patients who have progressed on irinotecan containing chemotherapy. Cetuximab is well tolerated and does not exacerbate the toxicity of concomitant chemotherapy. Furthermore, a series of phase III clinical trials are currently evaluating the combination of cetuximab with standard chemotherapy regimens in the first-line treatment chemotherapy-naïve patients with metastatic CRC.Oncogene (2007) 26, 3654–3660. doi:10.1038/sj.onc.1210381 [ABSTRACT FROM AUTHOR]

We have evaluated the activity and safety of gefitinib, a small-molecule epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, in combination with docetaxel as first-line treatment of women with metastatic breast cancer (MBC). In total, 41 patients with MBC were enrolled in a first-line combination therapy study with oral gefitinib (250 mg day(-1)) and intravenous docetaxel (75 mg m(-2), the first 14 patients; or 100 mg m(-2), the following 27 patients, on day 1 of a 3-week cycle). Out of 41 patients, 38 received at least one cycle of therapy. There were no differences in activity or tolerability between the two docetaxel doses. G3/4 toxicities were neutropenia (49%), diarrhoea (10%), acne-like rash (5%), and anaemia (2%). Complete plus partial responses (CR+PR) were observed in 22 out of 41 patients with a 54% response rate (95% confidence interval (CI) 45-75%). The 22 patients that achieved a response following six cycles of docetaxel plus gefitinib continued gefitinib monotherapy (median duration, 24 weeks; range, 2-108+ weeks). Two patients with PR following combination therapy achieved a CR during gefitinib monotherapy. Complete plus partial responses correlated with oestrogen receptor (ER) status, since they occurred in 19 out of 27 (70%) patients with ER-positive tumours as compared to three out of 14 (21%) patients with ER-negative tumours (P=0.01). [ABSTRACT FROM AUTHOR]

The aims of this multicentre, randomised phase III trial were to evaluate: (1) the role of levamisol (LEV); and (2) the role of folinic acid (FA), added to 5-fluorouracil (5FU) in the adjuvant treatment of colorectal cancer. Patients with histologically proven, radically resected stage II or III colon or rectal cancer were eligible. The study had a 2x2 factorial design with four treatment arms: (a) 5FU alone, (b) 5FU+LEV, (c) 5FU+FA, (d) 5FU+LEV+FA, and two planned comparisons, testing the role of LEV and of FA, respectively. From March 1991, to September 1998, 1327 patients were randomised. None of the two comparisons resulted in a significant disease-free (DFS) or overall (OAS) survival advantage. The hazard ratio (HR) of relapse was 0.89 (95% confidence intervals (CI): 0.73-1.09) for patients receiving FA and 0.99 (95% CI 0.80-1.21) for those receiving LEV; corresponding HRs of death were 1.02 (95% CI: 0.80-1.30) and 0.94 (95% CI 0.73-1.20). Nonhaematological toxicity (all grade vomiting, diarrhoea, mucositis, congiuntivitis, skin, fever and fatigue) was significantly worse with FA, while all other toxicities were similar. In the present trial, there was no evidence that the addition of FA or LEV significantly prolongs DFS and OAS of radically resected colorectal cancer patients. [ABSTRACT FROM AUTHOR]

The aim of the study was to assess the toxicity and the clinical activity of biweekly oxaliplatin in combination with infusional 5-fluorouracil (5-FU) and folinic acid (FA) administered every 2 weeks (FOLFOX-4 regimen) in patients with advanced gastric cancer (AGC). A total of 61 previously untreated AGC patients were treated with oxaliplatin 85?mg?m-2 on day 1, FA 200?mg?m-2 as a 2?h infusion followed by bolus 5-FU 400?mg?m-2 and a 22?h infusion of 5-FU 600?mg?m-2, repeated for 2 consecutive days every 2 weeks. All patients were assessable for toxicity and response to treatment. Four (7%) complete responses and 19 partial responses were observed (overall response rate, 38%). Stable disease was observed in 22 (36%) patients, with progressive disease in the other six (10%) patients. Median time to progression (TTP) and median overall survival (OS) were 7.1 and 11.2 months, respectively. National Cancer Institute Common Toxicity Criteria grade 3 and 4 haematologic toxicities were neutropenia, anaemia and thrombocytopenia in 36, 10 and 5%of the patients, respectively. Grade 3 peripheral neuropathy was recorded in three (5%) patients. FOLFOX-4 is an active and well-tolerated chemotherapy. Response rate (RR), TTP and OS were comparable with those of other oxaliplatin-based regimens, suggesting a role for this combination in gastric cancer.British Journal of Cancer (2005) 92, 1644-1649. doi:10.1038/sj.bjc.6602573 www.bjcancer.com Published online 26 April 2005 [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the safety and efficacy of biweekly irinotecan plus leucovorin-modulated 5-fluorouracil i.v. bolus in metastatic colorectal carcinoma according to the age of patients. For this purpose, we have analysed 108 patients randomly allocated to receive irinotecan 200 mg m(-2) i.v. (1-h infusion) on day 1, and L-leucovorin 250 mg m(-2) i.v. (1-h infusion) plus 5-fluorouracil 850 mg m(-2) i.v. bolus on day 2 every 2 weeks (IRIFAFU) in our previous SICOG 9801 trial. According to age, patients were retrospectively divided into three groups: younger (/=70 years, n=17). Apart from gender, pretreatment characteristics were well balanced across the three groups. WHO grade >/=3 neutropenia and diarrhoea affected on the whole 46 and 16 patients, respectively, without any significant difference according to age-grouping. Patients aged

The aim of the present study was to define the activity and tolerability of a triplet regimen including oxaliplatin 130 mg x m(-2) (2 h i.v. infusion) and raltitrexed 3.0 mg x m(-2) (15 min i.v. infusion) given on day 1, followed by levo-folinic acid 250 mg x m(-2) (2 h i.v. infusion) and 5-fluorouracil 1050 mg x m(-2) i.v. bolus on day 2, every 2 weeks, in pretreated colorectal cancer patients. From April 1999 to December 2000, 50 patients were enrolled: 26 were males and 24 females, their median age was 63 (range, 43-79) years; ECOG performance status was 0 in 26 patients, > or =1 in 24 patients; 26 patients had received previous adjuvant chemotherapy, 40 patients had been exposed to one or two lines of palliative chemotherapy (including irinotecan in 31 cases); 18 patients were considered chemo-refractory. A total of 288 cycles were administered, with a median number of 6 (range 1-12) courses per patient. A complete response was obtained in three patients, and a partial response in nine patients, giving a major response rate of 24% (95% confidence interval, 13-38%), while 15 further patients showed a stable disease, for an overall control of tumour growth in 60% of patients. Three complete responses and three partial responses were obtained in patients pretreated with irinotecan (response rate, 19%); among refractory patients, three achieved partial responses (response rate, 13%). After a median follow-up of 18 (range, 10-30) months, 40 patients showed a progression of disease: the growth modulation index ranged between 0.2 and 2.5: it was > or =1.33 (showing a significant delay of tumour growth) in 16 (40%) patients. Actuarial median progression-free survival time was 7.6 months, and median survival time was 13.6 months: estimated probability of survival was 55% at 1 year. Main severe toxicity was neutropenia: World Health Organisation grade 4 affected 32% of patients; non-haematological toxicity was mild: World Health Organisation grade 3 diarrhoea was complained of by 8%, and grade 3 stomatitis by 4% of patients; neurotoxicity (according to Lévi scale) was scored as grade 3 in 8% of patients. In conclusion, this regimen was manageable and active as salvage treatment of advanced colorectal cancer patients; it showed incomplete cross-resistance with irinotecan-based treatments, and proved to delay the progression of disease in a relevant proportion of treated patients. [ABSTRACT FROM AUTHOR]

The aim of the present study was to define the activity and tolerability of a triplet regimen including oxaliplatin 130 mg m[sup -2] (2 h i.v. infusion) and raltitrexed 3.0 mg m[sup -2] (15 min i.v. infusion) given on day 1, followed by levo-folinic acid 250 mg m[sup -2] (2 h i.v. infusion) and 5-fluorouracil 1050 mg m[sup -2] i.v. bolus on day 2, every 2 weeks, in pretreated colorectal cancer patients. From April 1999 to December 2000, 50 patients were enrolled: 26 were males and 24 females, their median age was 63 (range, 43-79) years; ECOG performance status was 0 in 26 patients, ≥ 1 in 24 patients; 26 patients had received previous adjuvant chemotherapy, 40 patients had been exposed to one or two lines of palliative chemotherapy (including irinotecan in 31 cases); 18 patients were considered chemo-refractory. A total of 288 cycles were administered, with a median number of 6 (range 1-12) courses per patient. A complete response was obtained in three patients, and a partial response in nine patients, giving a major response rate of 24% (95% confidence interval, 13-38%), while 15 further patients showed a stable disease, for an overall control of turnout growth in 60% of patients. Three complete responses and three partial responses were obtained in patients pretreated with irinotecan (response rate, 19%); among refractory patients, three achieved partial responses (response rate, 13%). After a median follow-up of 18 (range, 10-30) months, 40 patients showed a progression of disease: the growth modulation index ranged between 0.2 and 2.5: it was ≥ 1.33 (showing a significant delay of tumour growth) in 16 (40%) patients. Actuarial median progression-free survival time was 7.6 months, and median survival time was 13.6 months: estimated probability of survival was 55% at 1 year. Main severe toxicity was neutropenia: World Health Organisation grade 4 affected 32% of patients; non-haematological toxicity was mild: World Health Organisation grade 3 diarrhoea... [ABSTRACT FROM AUTHOR]