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31.
The aim of this paper is to underline the role of Sir James Mackenzie in stating that atrial fibrillation is a distinct and clinically important arrhythmia and that it is a common condition in patients with cardiac disease. Around 1900, a few clinical researchers were dealing with cardiac arrhythmias with the use of arterial and venous pulse tracings. Sir James Mackenzie, who has been one of the fathers of modern cardiology, introduced registration of the venous pulse at the bedside using the clinical polygraph he had invented. He applied the results of his experimental and clinical discoveries to the explanation of many kinds of arrhythmias before ECG introduction. In our paper, we have especially considered the three steps of his approach to atrial fibrillation, the first two developed in the pre-ECG era. The invention of an instrument of precision, the electrocardiograph, revolutionized the diagnosis of heart disease and catalyzed the formation of cardiology as a specialty.  相似文献   
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Although gold nanoparticles (AuNPs) are currently used in several industrial products and biomedical applications, information about their biological effects is very limited. Thus, it is becoming crucial to assess their safety and adequately investigate the complexity of cell–nanoparticles interactions. In this work, the Balb/3T3 mouse fibroblast cell line was selected as an in vitro model to study the effects of AuNPs. Alteration of cellular processes and biochemical pathways caused by AuNPs exposure was investigated by analysing the differentially expressed proteome. Of interest was the difference observed in the protein pattern expression of cells exposed to AuNPs. It was found that 88 and 83 proteins were de-regulated after exposure to 5 and 15 nm AuNPs, respectively. Analysis of the proteome revealed that AuNPs triggers several pathways related to cellular growth and proliferation, cell morphology, cell cycle regulation, cellular function and maintenance, oxidative stress, and inflammatory response. Moreover, SPR analysis showed an increase of ECM proteins biosynthesis in cells exposed to AuNPs. We observed by TEM analysis that NPs are internalized and confined mainly in autophagosomes. Endoplasmic reticulum stressed and modification at mitochondrial level occurred. This study aims to improve existing knowledge necessary for a correct assessment of the balance between AuNPs potential adverse and beneficial effects and might have important implications for biomedical applications (e.g. nanomedicine).  相似文献   
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AIM: To investigate efficacy and safety of second-line treatment with irinotecan-loaded drug-eluting beads (DEBIRI) and cetuximab (DEBIRITUX) of unresectable colorectal liver metastases.METHODS: Patients with the following characteristics were included in the study: unresectable hepatic metastases from colorectal carcinoma (CRC-LM), progression after first line chemotherapy (any type of chemotherapeutic drug and combination was allowed), second line treatment (mandatory), which included for each patient (unregarding the KRas status) two cycles of DEBIRI (using 100-300 μm beads loaded with irinotecan at a total dose 200 mg) followed by 12 cycles of cetuximab that was administered weekly at a first dose of 400 mg/m2 and then 250 mg/m2; good performance status (0-2) and liver functionality (alanine aminotransferase and gamma-glutamyl transferase not exceeding three times the upper limit of normal, total bilirubin not exceeding 2.5 mg/mL). Data were collected retrospectively and included: tumor response (evaluated monthly for 6 mo then every 3 mo), overall response rate (ORR), KRas status, type and intensity of adverse events (G according to the Common Terminology Criteria for Adverse Events v3.0, CTCAE), overall survival (OS) and progression free survival (PFS).RESULTS: Forty consecutive cases of CRC hepatic metastases were included in the study. Median duration of DEBIRITUX was 4.4 mo (range, 4.0-6.5). Sixteen patients (40%) received the planned 2 cycles of DEBIRI and an average of 10 cetuximab cycles. ORR of the whole sample was 50%, in particular 4 patients were complete responders (10%) and 16 (40%) partial responders. The most observed side effects (G2) were: post-embolization syndrome (30%), diarrhea (25%), skin rushes (38%) and asthenia (35%). The retrospective evaluation of KRas status (24 wild type, 16 mutated) showed that the group of patients with wild type KRas had ORR significantly higher than mutant KRas. Median follow-up was 29 mo (8-48 range); median PFS was 9.8 mo and OS was 20.4 mo. Future randomized trials are required in this setting to establish a role for DEBIRITUX compared with systemic chemotherapy.CONCLUSION: DEBIRITUX seems to be efficacious after first line chemotherapy for the treatment of unresectable CRC-LM.  相似文献   
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BACKGROUND: Although the process by which the left ventricular (LV) remodels in response to an injury generally leads to dilatation, in patients with heart failure (HF) the recognition of a small or mildly dilated left ventricle is not uncommon. We investigated the prevalence and the characteristics of elderly patients with traditional dilated and nondilated cardiomyopathy (CMP). We also assessed the response to the guideline-based medical therapy and the prognosis based on LV dilatation in this population. METHODS AND RESULTS: We selected 243 patients >70 years of age with HF and LV ejection fraction <40% who underwent clinical and echocardiographic evaluations at baseline and after 12 months. They were subdivided into 2 groups according to baseline LV end-diastolic volume (LVEDV) (values < or =78 mL/m(2) identified nondilated CMP). Nondilated CMP was recognized in 64 patients (26%) who showed at baseline better clinical status, less severe mitral regurgitation, and higher LV ejection fraction than those with dilated CMP. At the final evaluation, favorable changes in clinical and echocardiographic parameters could be detected in both groups. The magnitude of these variations did not differ between the groups. The risk of hospitalization for worsening HF was 2.4-fold higher in patients with nondilated than dilated CMP. Mortality was 11% and 20%, respectively (P = .06). Statistical analysis revealed a direct, approximately linear relationship between LVEDV and outcomes in this population. CONCLUSIONS: A total of 1 of 4 elderly patients with systolic HF had a nondilated left ventricle. These patients had a better clinical presentation than did counterparts with dilated left ventricles. After HF therapy is optimized, the likelihood of improvement is independent of LV size in this population, whereas the risk of death or worsening HF linearly increases with LV dilatation.  相似文献   
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BACKGROUND/AIMS: Experimental radiofrequency ablation has already been performed in healthy livers of porcine models, but not in less expensive and easy-to-manage rats, with devices capable of delivering radiofrequency ablation in the 20-30 g liver of such small animals being so far unavailable. METHODOLOGY: We experimented with a modified system of radiofrequency ablation of liver tissue in rat models developing a custom-made needle-microelectrode of very small dimensions (0.3x2 mm) and an electrode-tip cooling technique, based on saline solution infusion. We adjusted duration (seconds) and power (watts) of radiofrequency ablation letting them range between 5-50 seconds and 5-25 W, respectively, to obtain the greatest lesions with the least side effects. After sacrificing the animals, an accurate histological examination of the liver was made. RESULTS: It is possible to establish beforehand the diameter of thermal liver lesion on the basis of joules of applied energy. The greatest increase of liver thermal lesion diameter (8 mm) is obtained with a 250-joule (10 W for 25 seconds) thermal energy cooling the electrode-tissue interface. CONCLUSIONS: Experimental radiofrequency ablation in rat liver is an effective and cheap way to study its effects on healthy hepatic tissues. It might be the first step to treat experimentally caused liver tumors.  相似文献   
38.
Fludarabine plus cytarabine (Ara-C) and idarubicin (FLAI) is an effective and well-tolerated induction regimen for the treatment of acute myeloid leukaemia (AML). This phase III trial compared the efficacy and toxicity of FLAI versus idarubicin plus Ara-C and etoposide (ICE) in 112 newly diagnosed AML patients <60 years. Fifty-seven patients received FLAI, as the first induction-remission course, and 55 patients received ICE. Post-induction treatment consisted of high-dose Ara-C (HDAC). After HDAC, patients in complete remission (CR) received a second consolidation course (mitoxantrone, etoposide, Ara-C) and autologous stem cell transplantation (auto-SCT) or allogeneic (allo)-SCT, according to the age, disease risk and donor availability. After a single induction course, CR rate was 74% in the FLAI arm and 51% in the ICE arm (P = 0.01), while death during induction was 2% and 9% respectively. Both haematological (P = 0.002) and non-haematological (P = 0.0001) toxicities, especially gastrointestinal (i.e. nausea, vomiting, mucositis and diarrhoea), were significantly lower in FLAI arm. In both arms, relapses were more frequent in patients who were not submitted to allo-SCT. After a median follow-up of 17 months, 30% and 38% of the patients are in continuous CR in FLAI and ICE arm respectively. Our prospective randomised study confirmed the anti-leukaemic effect and the low toxic profile of FLAI as induction treatment for newly diagnosed AML patients.  相似文献   
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A specific subset of micro RNAs (miRs), including miR-133 and miR-206, is specifically expressed in muscle tissue, so that they are currently defined as muscular miRs (myomiRs). To further elucidate the role of myomiRs in muscle biology, we measured miR-133a and miR-206 in plasma of 28 middle-age recreational athletes. The study population consisted of 28 middle aged, recreation athletes (11 women and 17 men; mean age, 46?years) who completed a 21.1?km, half-marathon. The plasma concentration of miR-133a and miR-206, the serum concentration of creatine kinase (CK) and high-sensitivity (HS) cardiac troponin T (cTnT), as well as capillary lactate, were measured before and immediately after the run. The median serum concentration of total CK (257 versus 175?U/L; p?p??4; p??4; p?=?.001) were considerably increased immediately after the half-marathon run. In multivariate analysis only post-exercise capillary lactate was found to be independently associated with running time. A significant and independent correlation was observed between plasma variations of the two miRs, but not with other physiological or laboratory parameters. The results of this study suggest that the biological significance of miR-133a and 206 variation after middle-distance running parallels but not overlaps the release of biomarkers of nonspecific tissue damage. Enhanced plasma values of these myomiRs may hence reflect a physiological response to high-intensity and/or prolonged exercise rather than tissue injury.  相似文献   
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