25 research outputs found
Patterns of tumor response in canine and feline cancer patients treated with electrochemotherapy: preclinical data for the standardization of this treatment in pets and humans
Electrochemotherapy (ECT) is a novel anticancer therapy that is currently being evaluated in human and pet cancer patients. ECT associates the administration of an anti-tumor agent to the delivery of trains of appropriate waveforms. The increased uptake of chemotherapy leads to apoptotic death of the neoplasm thus resulting in prolonged local control and extended survival. In this paper we describe the histological features of a broad array of spontaneous tumors of companion animals receiving pulse-mediated chemotherapy. Multivariate statistical analysis of the percentage of necrosis and apoptosis in the tumors before and after ECT treatment, shows that only a high percentage of necrosis and apoptosis after the ECT treatment were significantly correlated with longer survivals of the patients (p < 0.0001 and p = 0.004, respectively). Further studies on this topic are warranted in companion animals with spontaneous tumors to identify new molecular targets for electrochemotherapy and to the develop new therapeutical protocols to be translated to humans
Increased myocardial apoptosis in patients with unfavorable left ventricular remodeling and early symptomatic post-infarction heart failure
AbstractObjectivesThe purpose of this study was to evaluate a potential correlation between apoptotic rate (AR), post-infarction left ventricular (LV) remodeling, and clinical characteristics in subjects who died late (≥10 days) after an acute myocardial infarction (AMI) with evidence of persistent occlusion of the infarct-related artery at autopsy.BackgroundApoptosis contributes to myocardiocyte loss in cardiac disease and may have a pathophysiologic role in post-infarction LV remodeling.MethodsThe AR was calculated at the site of infarction and in remote unaffected LV regions, using co-localization of in situ end labeling for deoxyribonucleic acid fragmentation and immunohistochemistry for caspase-3, in 14 subjects who died within two months after AMI. Correlation between AR and clinical characteristics such as age, site of AMI, transmural extension, multivessel coronary disease, and signs and/or symptoms of heart failure (HF), at the time of initial hospitalization for AMI or subsequently before death, was assessed using non-parametric statistical tests. Parameters of LV remodeling including diameters, free wall thickness, diameter-to-wall-thickness ratio, and mass were measured at gross examination at autopsy. Values are expressed as median (interquartile range).ResultsAmong clinical variables, early symptomatic post-infarction HF (9 cases, 64%) was associated with nearly fourfold increased AR at the site of infarction (26.2% [24.5% to 28.8%] vs. 6.4% [1.9% to 13.3%], p = 0.001). Moreover, AR both at the site of infarction and in unaffected regions was significantly correlated with parameters of progressive LV remodeling (p < 0.05).ConclusionsOur data show that in patients dying ≥10 days after AMI, myocardial apoptosis is strongly associated with and may be a major determinant of unfavorable LV remodeling and early symptomatic post-infarction HF
The Ubiquitin-Proteasome System and Inflammatory Activity in Diabetic Atherosclerotic Plaques
The role of ubiquitin-proteasome system in the accelerated atherosclerotic progression of diabetic patients is unclear. We evaluated ubiquitin-proteasome activity in carotid plaques of asymptomatic diabetic and nondiabetic patients, as well as the effect of rosiglitazone, a peroxisome proliferator–activated receptor (PPAR)-γ activator, in diabetic plaques. Plaques were obtained from 46 type 2 diabetic and 30 nondiabetic patients undergoing carotid endarterectomy. Diabetic patients received 8 mg rosiglitazone (n = 23) or placebo (n = 23) for 4 months before scheduled endarterectomy. Plaques were analyzed for macrophages (CD68), T-cells (CD3), inflammatory cells (HLA-DR), ubiquitin, proteasome 20S activity, nuclear factor (NF)-κB, inhibitor of κB (IκB)-β, tumor necrosis factor (TNF)-α, nitrotyrosine, matrix metalloproteinase (MMP)-9, and collagen content (immunohistochemistry and enzyme-linked immunosorbent assay). Compared with nondiabetic plaques, diabetic plaques had more macrophages, T-cells, and HLA-DR+ cells (P < 0.001); more ubiquitin, proteasome 20S activity (TNF-α), and NF-κB (P < 0.001); and more markers of oxidative stress (nitrotyrosine and O2− production) and MMP-9 (P < 0.01), along with a lesser collagen content and IκB-β levels (P < 0.001). Compared with placebo-treated plaques, rosiglitazone-treated diabetic plaques presented less inflammatory cells (P < 0.01); less ubiquitin, proteasome 20S, TNF-α, and NF-κB (P < 0.01); less nitrotyrosine and superoxide anion production (P < 0.01); and greater collagen content (P < 0.01), indicating a more stable plaque phenotype. Similar findings were obtained in circulating monocytes obtained from the two groups of diabetic patients and cultured in the presence or absence of rosiglitazone (7.0 μmol/l). Ubiquitin-proteasome over-activity is associated with enhanced inflammatory reaction and NF-κB expression in diabetic plaques. The inhibition of ubiquitin-proteasome activity in atherosclerotic lesions of diabetic patients by rosiglitazone is associated with morphological and compositional characteristics of a potential stable plaque phenotype, possibly by downregulating NF-κB-mediated inflammatory pathways
Ectopic endometrium in human foetuses is a common event and sustains the theory of müllerianosis in the pathogenesis of endometriosis, a disease that predisposes to cancer
<p>Abstract</p> <p>Background</p> <p>Endometriosis is a gynecological disease defined by the histological presence of endometrial glands and stroma outside the uterine cavity. Women with endometriosis have an increased risk of different types of malignancies, especially ovarian cancer and non-Hodgkin's lymphoma. Though there are several theories, researchers remain unsure as to the definitive cause of endometriosis. Our objective was to test the validity of the theory of müllerianosis for endometriosis, that is the misplacing of primitive endometrial tissue along the migratory pathway of foetal organogenesis</p> <p>Methods</p> <p>We have collected at autopsy 36 human female foetuses at different gestational age. We have performed a morphological and immunohistochemical study (expression of oestrogen receptor and CA125) on the pelvic organs of the 36 foetuses included en-block and totally analyzed.</p> <p>Results</p> <p>In 4 out of 36 foetuses we found presence of misplaced endometrium in five different ectopic sites: in the recto-vaginal septum, in the proximity of the Douglas pouch, in the mesenchimal tissue close to the posterior wall of the uterus, in the rectal tube at the level of muscularis propria, and in the wall of the uterus. All these sites are common location of endometriosis in women.</p> <p>Conclusion</p> <p>We propose that a cause of endometriosis is the dislocation of primitive endometrial tissue outside the uterine cavity during organogenesis.</p
Large expert-curated database for benchmarking document similarity detection in biomedical literature search
Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe
Increased apoptosis in remote non-infarcted myocardium in multivessel coronary disease
Background: Multivessel coronary disease after myocardial infarction is a major risk factor for unfavorable cardiac remodeling and death due to pump failure, but underlying pathophysiologic mechanisms are still uncompletely established. Post-infarction myocardial apoptosis has been recently implicated as a cause of ongoing cell loss leading to cardiac failure. Our aim was to assess the role of post-infarction myocardial apoptosis and pro-apoptotic factor expression in the non-infarcted remote myocardium of subjects with multivessel coronary disease. Methods: Twenty-one males dying after recent myocardial infarction with permanent occlusion of the infarct-related artery were selected at autopsy. Apoptosis was assessed at viable myocardial regions remote from infarction by co-staining for in situ end-labeling of DNA fragmentation and cleaved caspase-3. Expression of pro-apoptotic factor bax and hypoxia-induced factor-1 alpha was evaluated by immunohistochemistry. Results: Subjects with multivessel disease (N = 11) showed a significantly two-fold higher myocardial apoptosis in comparison to subjects with single vessel disease (N = 10) (0.9% vs. 0.5%,p = 0.013). Similarly, myocardial bax expression was increased in patients with multivessel disease (3.0% vs. 1.4%, p = 0.029). Stratification for the number of diseased coronary vessels confirmed the association between extent of coronary disease and apoptotic rates (p = 0.022). Even in subjects dying over 30 days after infarction multivessel disease remained predictive of enhanced myocardiocyte apoptosis at remote regions (p = 0.033). Conclusions: Post-infarction myocardial apoptosis and bax expression in remote left ventricular regions are significantly increased in male patients with multivessel coronary disease in comparison to those with isolated infarct-related artery occlusion. These findings suggest that apoptotic cell loss in the viable non-infarcted myocardium, possibly due ongoing ischemia, may play a relevant role in the unfavorable clinical course typical of multivessel disease after myocardial infarction. (C) 2004 Published by Elsevier Ireland Ltd