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81.
Roberto Marchioli Guido Finazzi Raffaele Landolfi Jack Kutti Heinz Gisslinger Carlo Patrono Raphael Marilus Ana Villegas Gianni Tognoni Tiziano Barbui 《Journal of clinical oncology》2005,23(10):2224-2232
PURPOSE: The clinical course of polycythemia vera is often complicated by thrombosis as well as by the possible transition to myeloid metaplasia with myelofibrosis or acute myeloid leukemia. The aim of this study was to assess the rate of these complications in subjects receiving currently recommended treatments. PATIENTS AND METHODS: Overall, 1,638 patients from 12 countries were enrolled onto a large, prospective multicenter project aimed at describing the clinical history of polycythemia vera for the following outcomes: survival, the cumulative rate of cardiovascular death and thrombosis, the cumulative rate of leukemia, myelodysplasia, and myelofibrosis. The mean duration of the disease at entry and the duration of the follow-up were 4.9 and 2.7 years, respectively. RESULTS: The overall mortality rate of 3.7 deaths per 100 persons per year resulted from a moderate risk of cardiovascular death and a high risk of death from noncardiovascular causes (mainly hematologic transformations). Age older than 65 years and a positive history of thrombosis were the most important predictors of cardiovascular events. Antiplatelet therapy, but not cytoreductive treatment, was significantly associated with a lower risk of cardiovascular events. We found a consistent association between age and risk of leukemia, and between duration of the disease with risk of myelofibrosis. CONCLUSION: The European Collaboration on Low-Dose Aspirin in Polycythemia Vera study documents that large international collaborative studies are feasible in this field, in which few epidemiologic data are available. The persistently high mortality rate from hematologic malignancies characterizes the unmet therapeutic need of polycythemic patients and suggests a priority for future studies in this disease. 相似文献
82.
Kathleen McIntyre-Seltman Philip E Castle Richard Guido Mark Schiffman Cosette M Wheeler 《Cancer epidemiology, biomarkers & prevention》2005,14(5):1165-1170
BACKGROUND: Smoking is a potential risk factor for cervical cancer and its immediate precursor, cervical intraepithelial neoplasia grade 3 (CIN3), but few studies have adequately taken into account the possible confounding effect of oncogenic human papillomavirus (HPV) infection. METHODS: Women (n = 5,060) with minimally abnormal Papanicolaou smears were enrolled in the ASCUS and LSIL Triage Study, a clinical trial to evaluate management strategies, and were seen every 6 months for the 2-year duration of the study. Cervical specimens were tested for HPV DNA using both Hybrid Capture 2 and PGMY09/11 L1 consensus primer PCR with reverse line blot hybridization for genotyping. Multivariate logistics regression models were used to assess associations [odds ratio (OR) with 95% confidence intervals (95% CI)] between smoking behaviors and rigorously reviewed cases of cervical intraepithelial neoplasia grade 3 or cancer (> or =CIN3) identified throughout the study (n = 506) in women with oncogenic HPV (n = 3,133). RESULTS: Current smoking was only weakly associated with increased HPV infection. Among infected women, current smokers (OR, 1.7; 95% CI, 1.4-2.1) and past smokers (OR, 1.7; 95% CI, 1.2-2.4) were more likely to be diagnosed with > or =CIN3 than nonsmokers. Greater smoking intensity (P(Trend) < 0.0005) and duration (P(Trend) < 0.0005) increased the strength of the association, with smoking > or =2 packs/d (OR, 3.3; 95% CI, 1.5-7.5) and smoking for > or =11 years (OR, 2.1; 95% CI, 1.5-2.9) most strongly associated with > or =CIN3 as compared to non-smokers. The effects of intensity and duration seemed additive. CONCLUSIONS: Women with oncogenic HPV and minimally abnormal Papanicolaou smears who smoke were up to three times more likely to be diagnosed with > or =CIN3 than nonsmokers. Smoking cessation trials targeting this population might be warranted. 相似文献
83.
Malte Buchholz Hans A Kestler Andrea Bauer Wolfgang B?ck Bettina Rau Gerhard Leder Wolfgang Kratzer Martin Bommer Aldo Scarpa Martin K Schilling Guido Adler J?rg D Hoheisel Thomas M Gress 《Clinical cancer research》2005,11(22):8048-8054
PURPOSE: Malignant tumors of the pancreas are frequently indistinguishable from inflammatory tumors arising in the context of a chronic pancreatitis with the use of conventional imaging techniques. Thus, cytologic analysis of cells obtained by abdominal ultrasound, computed tomography, or endoscopic ultrasound-guided fine needle aspiration biopsy is required for diagnosis. However, the reliability of cytologic analyses of pancreatic fine needle aspirates remains unsatisfactory, with a diagnostic accuracy of < or =80%. The purpose of the current study was therefore to develop a novel diagnostic approach based on expression profiling of biopsy material using a specialized diagnostic cDNA array. EXPERIMENTAL DESIGN: Previous gene expression profiling studies were reevaluated to design a 558-feature diagnostic array. Minimal amounts of residual material from pancreatic cytology samples as well as surgically resected tumor and control tissue specimens were analyzed using the diagnostic array and a newly developed statistical classification system. RESULTS AND CONCLUSIONS: Our diagnostic approach resulted in 95% accurate differentiation between ductal adenocarcinomas and nonmalignant tumors of the pancreas. The diagnostic array, in conjunction with conventional diagnostic procedures, is thus suitable to significantly improve the reliability of pancreatic cancer diagnostics and can be expected to become a valuable new tool in the routine workup of suspect masses in the pancreas. 相似文献
84.
Lorenzo Fornaro Gianna Musettini Paola Orlandi Irene Pecora Caterina Vivaldi Marta Banchi Francesca Salani Elisabetta Fini Valentina Massa Silvia Catanese Federico Cucchiara Monica Lencioni Gianluca Masi Enrico Vasile Guido Bocci 《American journal of cancer research》2022,12(7):3347
Ramucirumab plus paclitaxel is considered the standard of care in the second-line treatment of gastric carcinoma (GC). The aim of this study was to evaluate plasma vascular endothelial growth factor-A (VEGF-A), VEGF-D, and circulating soluble VEGF receptor-2 (sVEGFR-2) as possible markers of resistance or response to ramucirumab administered with paclitaxel in pretreated metastatic GC patients. Plasma samples were collected at different time points (on days 1 and 15 of the first 3 cycles, at best radiologic response and at disease progression). VEGF-A, VEGF-D and sVEGFR-2 were analysed by ELISA. Correlations of biomarker baseline levels or dynamic changes with outcome measures were assessed. Progression-free survival (PFS) was the primary endpoint of the study. Forty-one patients were enrolled. VEGF-A and VEGF-D, but not sVEGFR-2, values significantly increased during treatment compared to baseline (P < 0.001). A positive correlation between VEGF-A and sVEGFR-2 at cycle 2 was found (P=0.045). At univariate analysis, higher baseline levels of VEGF-A were associated with worse OS (P=0.015). Early increase of sVEGFR-2 levels after the first treatment cycle was the only factor associated with longer PFS (6.6 vs. 3.6 months, P=0.049) and OS (18.6 vs. 5.2 months, P=0.008). Significance of sVEGFR-2 early increase was retained at multivariate analysis for OS (HR 0.32; 95% CI 0.12-0.91; P=0.032). The reported results confirmed the prognostic role of baseline VEGF-A and, with the limitations of the limited sample size and the lack of a control arm, suggested that the early increase of sVEGFR-2 after 1 cycle of treatment could be a potential predictive biomarker of benefit from second-line ramucirumab plus paclitaxel in GC. 相似文献
85.
86.
Donatella Panatto Andrea Orsi Bianca Bruzzone Valentina Ricucci Guido Fedele Giorgio Reiner Nadia Giarratana Alexander Domnich Giancarlo Icardi STX Study Group 《Viruses》2022,14(5)
Sentinox (STX) is an acid-oxidizing solution containing hypochlorous acid in spray whose virucidal activity against SARS-CoV-2 has been demonstrated. In this paper, results of a randomized controlled trial (RCT) on the efficacy of STX in reducing viral load in mild COVID-19 patients () and a complementary in vitro study on its activity against different respiratory viruses are reported. In the RCT, 57 patients were randomized (1:1:1) to receive STX three (STX-3) or five (STX-5) times/day plus standard therapy or standard therapy only (controls). Compared with controls, the log10 load reduction in groups STX-3 and STX-5 was 1.02 (p = 0.14) and 0.18 (p = 0.80), respectively. These results were likely driven by outliers with extreme baseline viral loads. When considering subjects with baseline cycle threshold values of 20–30, STX-3 showed a significant (p = 0.016) 2.01 log10 reduction. The proportion of subjects that turned negative by the end of treatment (day 5) was significantly higher in the STX-3 group than in controls, suggesting a shorter virus clearance time. STX was safe and well-tolerated. In the in vitro study, ≥99.9% reduction in titers against common respiratory viruses was observed. STX is a safe device with large virucidal spectrum and may reduce viral loads in mild COVID-19 patients. NCT04909996相似文献
87.
Chen SN Lankin DC Nikolic D Fabricant DS Lu ZZ Ramirez B van Breemen RB Fong HH Farnsworth NR Pauli GF 《Journal of natural products》2007,70(6):1016-1023
Extracts from the roots and rhizomes of black cohosh (Cimicifuga racemosa) are widely used as dietary supplements to alleviate menopausal symptoms. State-of-the-art quality control measures involve phytochemical fingerprinting of the triterpene glycosides for species identification and chemical standardization by HPLC. In the course of developing materials and methods for standardization procedures, the major C. racemosa triterpene glycoside (1) was isolated and initially thought to be cimicifugoside (2). Detailed HR-LC-MS and 1D and 2D NMR analysis of 1 and 2 unambiguously revealed that 1 is the chlorine-containing derivative of 2, namely, 25-chlorodeoxycimigenol-3-O-beta-d-xyloside. Accordingly, HPLC profiles of black cohosh preparations require revision of the assignments of the chlorinated (1) and nonchlorinated (2) pair. Besides explaining the substantial shift in polarity (DeltatR[RP-18] ca. 20 min), 25-deoxychlorination opens a new pathway of structural diversification in triterpene glycoside chemistry. As chemical conversion of 2 into 1 could be demonstrated, deoxychlorination may be interpreted as artifact formation. Simultaneously, however, it is a potentially significant pathway for the gastric in vivo conversion ("nature's prodrug") of the relatively polar triterpene glycosides into significantly less polar chlorinated derivatives with altered pharmacological properties. 相似文献
88.
Chen P Aimiuwu J Xie Z Wei X Liu S Klisovic R Marcucci G Chan KK 《The AAPS journal》2011,13(1):131-140
GTI-2040 is a potent antisense to the M2 subunit of the ribonucleotide reductase (RNR), an enzyme involved in the de novo synthesis of nucleoside triphosphates. We hypothesized that combination of GTI-2040 with the cytarabine (Ara-C) could result in an enhanced cytotoxic effect with perturbed intracellular deoxynucleotide/nucleotide (dNTP/NTP) pools including Ara-C triphosphate (Ara-CTP). This study aims to provide a direct experimental support of this hypothesis by monitoring the biochemical modulation effects, intracellular levels of Ara-CTP, dNTPs/NTPs following the combination treatment of Ara-C, and GTI-2040 in K562 human leukemia cells. GTI-2040 was introduced into cells via electroporation. A hybridization-ligation ELISA was used to quantify intracellular GTI-2040 concentrations. Real-time PCR and Western blot methods were used to measure the RNR M2 mRNA and protein levels, respectively. 3-(4,5-Dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt assay was used to measure the cytotoxicity following various drug treatments. A non-radioactive HPLC-UV method was used for measuring the intracellular Ara-CTP, while a LC-MS/MS method was used to quantify intracellular dNTP/NTP pools. GTI-2040 was found to downregulate M2 mRNA and protein levels in a dose-dependent manner and showed significant decrease in dNTP but not NTP pool. When combining GTI-2040 with Ara-C, a synergistic cytotoxicity was observed with no further change in dNTP/NTP pools. Importantly, pretreatment of K562 cells with GTI-2040 was found to increase Ara-CTP level for the first time, and this effect may be due to inhibition of RNR by GTI-2040. This finding provides a laboratory justification for the current phase I/II evaluation of GTI-2040 in combination with Ara-C in patients with acute myeloid leukemia. 相似文献
89.
Rationale:Whereas metronidazole-induced hepatotoxicity is quite rare in the general population, in individuals carrying a nucleotide excision repair disorder, namely Cockayne syndrome, there is a high risk of developing this complication.Patient concerns:We report the case of a 44-year-old man, affected by xeroderma pigmentosum, who was admitted to the hospital presenting aspiration pneumoniae caused by worsening dysphagia and with severe hepatotoxicity during the hospitalization.Diagnoses:Acute hepatitis, which was leading to acute liver failure, occurred during antibiotic treatment with metronidazole and ceftazidime with an elevation of liver enzymes consistent with hepatocellular damage pattern.Interventions:Hydration with glucose 5% solution, pantoprazole and vitamin K were administered, meanwhile other causes of hepatitis were ruled out and the ongoing antibiotic treatment was stopped suspecting a drug-induced liver injury.Outcomes:Liver function nearly completely recovered 1 month later with a first rapid improvement, within few days, of aminotransferases and coagulation studies, and slower of cholestatic enzymes.Lessons:We describe the first case available in the literature of hepatotoxicity associated with metronidazole treatment in a xeroderma pigmentosum patient. Clinicians therefore, based on this report and according to the possible underlying mechanism shared by other genetic diseases characterized by alterations in the pathway of DNA-repair, should consider such adverse event also in patients affected by this rare disease. 相似文献
90.
Stefan Pleus Andreas Stuhr Manuela Link Cornelia Haug Guido Freckmann 《Journal of diabetes science and technology》2022,16(3):649
Background:There is an increasing use of continuous glucose monitoring (CGM) by people with diabetes. Measurement performance is often characterized by the mean absolute relative difference (MARD). However, MARD is influenced by a number of factors and little is known about whether MARD is stable throughout the day.Material and Methods:A total of 24 participants with type 1 diabetes were enrolled in the study. The study was performed for seven in-patient days. Participants wore two CGM systems in parallel and performed additional frequent blood glucose (BG) measurements. On two days, glucose excursions were induced.MARD was calculated between pairs of CGM and BG values, with BG values serving as reference values. ARD values calculated from CGM-BG pairs were grouped by hour of the day. Results were analyzed separately for glucose excursion days and for regular days.Results:Total MARDs for the complete study duration were 12.5% ± 3.6% and 13.2% ± 2.4% (n = 24). Throughout the day marked variability of MARD was observed (8.0% ± 1.3%-16.3% ± 2.9% (G5); 9.1% ± 1.4%-16.3% ± 5.3% (FL), up to n = 157 each). Low(est) MARD values were observed before breakfast and dinner, when subjects were in or near a fasting state. Especially after breakfast and lunch, MARD values were higher than average.Conclusions:Analytical performance of the two CGM systems, assessed by MARD, was found to vary markedly throughout the day. Activities of daily life likely triggered these variations. An increasing number of CGM users base therapeutic decisions on CGM values, and they should be aware of these variations of performance throughout the day. 相似文献