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51.
Genital human papillomaviruses (HPV) represent the most common sexually transmitted agents and are classified into low or high risk by their propensity to cause genital warts or cervical cancer, respectively. Topical microbicides against HPV may be a useful adjunct to the newly licensed HPV vaccine. A main objective in the development of novel microbicides is to block HPV entry into epithelial cells through cell surface heparan sulfate proteoglycans. In this study, selective chemical modification of the Escherichia coli K5 capsular polysaccharide was integrated with innovative biochemical and biological assays to prepare a collection of sulfated K5 derivatives with a backbone structure resembling the heparin/heparan biosynthetic precursor and to test them for their anti-HPV activity. Surface plasmon resonance assays revealed that O-sulfated K5 with a high degree of sulfation [K5-OS(H)] and N,O-sulfated K5 with a high [K5-N,OS(H)] or low [K5-N,OS(L)] sulfation degree, but not unmodified K5, N-sulfated K5, and O-sulfated K5 with low levels of sulfation, prevented the interaction between HPV-16 pseudovirions and immobilized heparin. In cell-based assays, K5-OS(H), K5-N,OS(H), and K5-N,OS(L) inhibited HPV-16, HPV-18, and HPV-6 pseudovirion infection. Their 50% inhibitory concentration was between 0.1 and 0.9 mug/ml, without evidence of cytotoxicity. These findings provide insights into the design of novel, safe, and broad-spectrum microbicides against genital HPV infections.  相似文献   
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We previously demonstrated that the inhibition of the epidermal growth factor receptor (EGFR) signalling affects the endocrine therapy responses of prostate cancer (PCa) cells and that bicalutamide (BCLT) is able to reinforce PI3K activity through mechanisms involving PTEN decrement and EGFR and Her2 activities. The aim of this study was to evaluate if the hormonal therapy with BCLT can affect the EGFR-targeted therapy using primary cultures obtained from 22 human PCa tissues harvested after radical prostatectomy (RP) in patients who received (n=10) BCLT and those that did not (n=12) as neoadjuvant hormone therapy (NHT). We demonstrated that cultures derived from PCa tissues harvested after NHT presented significantly higher EGFR and Her2 levels compared to cultures derived from control patients. However, cultures derived from patients with NHT were less sensitive to gefitinib when compared to cultures derived from control patients. Conversely, BCLT effectiveness did not seem to be different in the two groups and was partially additive with gefitinib in the NHT group and additive/synergistic in the control group. Cultures (8/22) were negative for the expression of the PTEN gene and we observed no differences in the two groups. Thus the different IC50 values observed for gefitinib and the partial additivity in the combination treatment with gefitinib and BCLT is influenced by EGFR/Her2 ratio because it was shown that EGFR inhibition was lower when Her2 is overexpressed. Taken together, our results indicate that anti-EGFR targeted therapies and a possible combination therapy involving gefitinib and BCLT should be performed early in naive patients when Her2 is not overexpressed and before the anti-androgenic hormone therapy induces such an undesirable effect.  相似文献   
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BACKGROUND: The aim was to investigate the cardiac response during liver transplantation (LT) and analyze its relationship with clinical factors, echocardiographic, and hemodynamic findings. METHODS: All patients undergoing LT for cirrhosis from 1998 to 2004 were included. Clinical data, comprehensive echocardiography, hepatic, and right heart hemodynamic measurements were analyzed. During LT patients underwent continuous right-heart pressure monitorization. Measurements 10 min after reperfusion were compared with baseline values. Abnormal cardiac response was defined as a decrease in left ventricular stroke work index despite a rise in pulmonary wedge capillary pressure. Predictors of abnormal cardiac response were investigated using logistic regression. RESULTS: Data were available from 209 patients (mean age 52 (9) yrs; Child A 27; B 93; C 89) with a mean model for end-stage liver disease score 16.3 (4.7). Abnormal cardiac response was observed in 47 (22.5%) patients after reperfusion. Patients who developed this response had hyponatremia, lower central venous pressure, lower pulmonary artery pressure, and lower pulmonary wedged capillary pressure. Abnormal cardiac response was related to a longer postoperative intubation time. CONCLUSION: Abnormal cardiac response is observed during LT and may be a manifestation of occult cirrhotic cardiomyopathy. This finding is underestimated with usual diagnostic tools and could be related to indirect signs of circulatory dysfunction of advanced liver disease.  相似文献   
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We investigated the effects of a single s.c. injection of peg-filgrastim in 32 patients with multiple myeloma who underwent autologous stem cell transplantation (AuSCT) as first line treatment. For comparison, 32 myeloma patients with similar characteristics and receiving standard daily administration of filgrastim were matched. Overall, there were no statistically significant differences between peg-filgrastim and filgrastim in terms of tolerability, marrow recovery, severity of neutropenia, incidence and duration of febrile neutropenia, documented infections and transfusions. However, some favourable trends or effects in favour of peg-filgrastim were observed. This was confirmed by a review of the published papers about this topic.  相似文献   
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BACKGROUND: Different methods of normalizing left ventricular (LV) mass for body size identify generally similar relative risks of adverse cardiovascular outcome but with variable prevalences of LV hypertrophy (H). Preliminary results from a population with high prevalence of obesity suggest that the population attributable-risk percent (PAR%) of LVH is substantially higher when LV mass is normalized for allometric power of height. METHODS: We calculated the PAR% of LVH by different definitions in the cohort of the MAssa Ventricolare sinistra nell' Ipertensione (MAVI) study (n = 1019, 62% women), a population with low prevalence of obesity (22%, with only 3% and 0.1% in class II and class III obesity, respectively). Composite fatal and nonfatal cardiovascular events occurred in 53 participants (5.2%). RESULTS: Prevalence of LVH was between 28% and 56%, with slight greater values for height-based normalization. Age- and sex-adjusted hazard ratios were comprised between 1.37 and 1.44 for different measures of LV mass index. The PAR% was not meaningfully different among the different methods of normalization (between 47% and 56%), and height-based methods showed in general a performance similar to body surface area-based normalizations. CONCLUSIONS: In a large clinical population of hypertensive subjects with low prevalence of obesity, population risk attributable to LV hypertrophy was not meaningfully different in relation to the type of normalization of LV mass for body size. Height-based methods perform as well as body surface area-based ones. We suggest that the prevalence of obesity in hypertensive populations might substantially influence differences in population risk attributable to LVH identified by different methods of normalizing LV mass.  相似文献   
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Sixty-one cases of Aspergillus infection (35 acute myeloid leukemia, 15 acute lymphoid leukemia, one myelodysplastic syndrome, two aplastic anemia, eight non-Hodgkin's lymphoma) seen in our department between January 1989 and July 1999 were studied retrospectively to evaluate the clinical characteristics, to ascertain the factors that influenced the outcome from mycotic infections, and whether early diagnosis and prolonged therapy permitted completion of scheduled intensive chemotherapy and bone marrow transplantation (BMT) without fungal recurrence. The patients were divided into three diagnostic categories: proven aspergillosis (autoptic or histologic diagnosis) n = 39, probable aspergillosis (radiological diagnosis with positive microbiology) n = 9, and possible aspergillosis (radiological diagnosis alone) n = 13. In the same period among 675 acute leukemia patients the incidence of proven or probable aspergillosis was 7.1%. At onset of infection 92% of patients were neutropenic (< 0.5 x 10(9)/L). The most frequent site of infection was the lung (90%); disseminated disease was present in 20 patients. Among 44 assessable patients, 12 (27%) failed to respond to early antifungal therapy and died. Thirty-two patients were cured with antifungal treatment, three of five nonneutropenic with only itraconazole, the others with amphotericin B 1 mg/Kg/day with or without itraconazole subsequently or with liposomal amphotericin, Ambisome, if renal toxicity occurred. Twenty-four of 29 neutropenic responders, all affected by acute leukemia, continued scheduled intensive chemotherapies. Pulmonary lobectomy was successfully combined with medical treatment in two cases before scheduled BMT. After infection nine patients were submitted to BMT (six allo, one marrow unrelated donor (MUD), two auto) with Ambisome or itraconazole as secondary prophylaxis without fungal relapse (follow-up: 25-99 months). The median time from fungal infection to transplant was five months, range 3-10. Thirteen of 29 surviving patients had leukemia relapse, but only three (23%) of these showed also fungal infection recurrence. In conclusion, a high index of suspicion and careful clinical and radiological examinations are the key to identifying infected patients early and to programming the following therapeutic steps. Above all in leukemia patients, prompt and aggressive administration of antifungal agents seems to improve the outcome of invasive fungal disease and to permit intensive chemotherapy completion and transplant.  相似文献   
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