Eduardo Paulino Júnior

Photopolymerizable and injectable polyurethanes for biomedical applications: synthesis and biocompatibility.

Two types of photopolymerizable and injectable polyurethane acrylates (PUAs), based on poly(propylene glycol) or poly(caprolactone diol) and hydroxyethyl methacrylate, were synthesized and characterized in order to obtain information regarding their use as an injectable material for biomedical applications. Structural characteristics of the biomaterials, including the degree of phase separation, were evaluated by Fourier transform infrared spectroscopy. The viscosities of the obtained biomaterials make them suitable for injection, molding and photopolymerization using visible light, as demonstrated by the injection test. The cured polymers had mechanical properties comparable to those of certain soft tissues, such as skin. An in vitro cell-polyurethane cytotoxicity study was carried out with mesenchymal stem cells from rat tibias and femurs. The proliferation/viability of the cells in the presence of the synthesized material was assessed by the MTT assay, collagen synthesis analysis and the expression of alkaline phosphatase. The results that were obtained through the in vitro tests indicated that PUAs are cytocompatible. The in vivo experiments were correlated with the in vitro tests and showed low levels of toxicity for the obtained biomaterials. Histology cross-sections showed that the biomaterials induced no significant inflammatory reaction. Our study demonstrates the potential for using synthesized photocurable polyurethanes in biomedical applications. Furthermore, the obtained injectable polymer systems employ minimally invasive procedures and can be molded in situ before photopolymerization with visible light.

Coronary Giant Cell Arteritis and Acute Myocardial Infarction

Giant cell arteritis (GCA) is a systemic immune-mediated granulomatous vasculitis of large- and medium-sized arteries mainly affecting elderly people. Death from GCA alone is rare and usually results of ruptured aorta. In this paper is reported a case of a 83-year-old woman who unexpectedly died during treatment of GCA. Necropsy revealed inflammatory involvement of the coronary arteries with left descendent anterior artery thrombosis, myocardial infarct and rupture of the anterior wall of the left ventricle, as well as hemopericardium and cardiac tamponade. Myocardial infarction leading to sudden death is an exceptional complication of GCA.

Individualized threshold for tumor segmentation in 18F-FDG PET/CT imaging: The key for response evaluation of neoadjuvant chemoradiation therapy in patients with rectal cancer?

INTRODUCTION The standard treatment for locally advanced rectal cancer (RC) consists of neoadjuvant chemoradiation followed by radical surgery. Regardless the extensive use of SUVmax in 18F-FDG PET tumor uptake as representation of tumor glycolytic consumption, there is a trend to apply metabolic volume instead. Thus, the aim of the present study was to evaluate a noninvasive method for tumor segmentation using the 18F-FDG PET imaging in order to predict response to neoadjuvant chemoradiation therapy in patients with rectal cancer. METHOD The sample consisted of stage II and III rectal cancer patients undergoing 18F-FDG PET/CT examination before and eight weeks after neoadjuvant therapy. An individualized tumor segmentation methodology was applied to generate tumor volumes (SUV2SD) and compare with standard SUVmax and fixed threshold (SUV40%, SUV50% and SUV60%) pre- and post-therapy. Therapeutic response was assessed in the resected specimens using Dworaks protocol recommendations. Several variables were generated and compared with the histopathological results. RESULTS Seventeen (17) patients were included and analyzed. Significant differences were observed between responders (Dworak 3 and 4) and non-responders for SUVmax-2 (p<0.01), SUV2SD-2 (p<0.05), SUV40%-2 (p<0.05), SUV50%-2 (p<0.05) and SUV60%-2 (p<0.05). ROC analyses showed significant areas under the curve (p<0.01) for the proposed methodology with sensitivity and specificity varying from 60% to 83% and 73% to 82%, respectively. CONCLUSION The present study confirmed the predictive power of the variables using a noninvasive individualized methodology for tumor segmentation based on 18F-FDG PET/CT imaging for response evaluation in patients with rectal cancer after neoadjuvant chemoradiation therapy.

18F-FDG PET/CT as a prognostic factor in penile cancer

PurposePenile cancer (PC) is a rare neoplasm with an aggressive behavior and variable prognosis. Lymph node (LN) involvement and pathological features of the primary lesion have been proven to be the most important survival factors. Positron emission tomography/computed tomography with fluorodeoxyglucose labelled with fluorine-18 (18F-FDG PET/CT) provides information on tumor staging and works as a prognostic factor, with promising results in other carcinomas. The aim of the present study is to evaluate PET/CT as a prognostic factor in PC.MethodsFifty-five patients (mean age 56.6 y) diagnosed with penile squamous cell carcinoma were prospectively evaluated from 2012 to 2014. All subjects underwent 18F-FDG PET/CT before treatment and were regularly followed after surgery.ResultsOut of the 53 patients selected, 17 (32.1%) had localized disease (cT1–2) and 24 (45.3%) had palpable nodes (cN+). Partial penile amputation was performed in 38 patients (71.7%) and inguinal lymphadenectomy (LND) in 30 (56.6%). From the LND group, 16 (53.3%) presented with positive neoplastic cells (pN+). Patients with more aggressive disease had a significantly (p = 0.019) higher 18F-FDG tumor uptake (pSUVmax), while inguinal LN uptake (nSUVmax) was able to recognize metastatic LN (p = 0.039). Some pathological prognostic features, when presented, have shown significant changes in pSUVmax values. Receiver operating characteristic (ROC) curves were performed and specific cutoff values of pSUVmax were evaluated to determine sensitivity and specificity. Regarding regional LNs, PET/CT presented a 76.2% accuracy in cN+ patients. After a 39-month follow up, pSUVmax of 16.6 (p = 0.0001) and nSUVmax of 6.5 (p = 0.019) were established as the ideal values to predict cancer-specific survival. The multivariate analysis confirmed nSUVmax as a predictor for LN metastasis (p = 0.043) and pSUVmax as a mean to estimate survival rate (p = 0.05).ConclusionThis study showed promising results on the use of 18F-FDG PET/CT as a prognostic tool for PC, using specific cutoff values of pSUVmax and nSUVmax.

Immunohistochemical Coexpression of Epithelial Cell Adhesion Molecule and Alpha-Fetoprotein in Hepatocellular Carcinoma

Background and Aim The epithelial cell adhesion molecule (EpCAM) has been proposed as a marker for cancer stem cells in human hepatocellular carcinoma (HCC) as well as in the development of novel target therapies. This study aimed to investigate the immunohistochemical expression of EpCAM and alpha-fetoprotein (AFP) in HCC patients and their association with clinicopathological characteristics. Methods This study included Child-Pugh A HCC patients undergoing curative surgical resection. Results A significant difference was observed in the ratio between the different phenotypes (p = 0.002), identifying 12 (29.3%) EPCAM positive tumors and 29 (70.7%) negative tumors. EpCAM+ expression was associated with AFP + (OR = 12.5, 95% CI, 1.9-84.1, p<0.001). In univariate analysis, a significant association was observed between AFP+ and EPCAM+ and the serum AFP level. A diameter of ≤ 5 cm was associated with EPCAM+, while angiolymphatic invasion was associated with APF+. In a multivariate analysis, only tumors of ≤ 5 cm were significantly associated with EpCAM+ (OR = 8.7; 95%CI, 1.27-100.0; p = 0.022). The overall survival rate was 74.9%, 69.4%, 69.4%, and 53.5% at 12, 24, 36, and 48 months, respectively. Conclusion A considerable number of patients with EpCAM+ HCC would benefit from a specific target therapy.

Disseminated mycosis in a patient with yellow fever

Disseminated mycosis (DM)—with cardiac involvement and shock—is an unexpected and severe opportunistic infection in patients with yellow fever. DM can mimic bacterial sepsis and should be considered in the differential diagnosis of causes of systemic inflammatory response syndrome in this group of patients, especially in areas where an outbreak of yellow fever is ongoing. We report the case of a 53-year-old male patient who presented to the emergency department with fever, myalgia, headache, and low back pain. The laboratory investigation revealed a positive molecular test for yellow fever, hepatic injury, and renal failure. During hospitalization, the patient developed hepatic encephalopathy, ascending leukocytosis, and ascites, with signs consistent with peritonitis. On the 11th day of hospitalization, the patient developed atrioventricular block, shock and died. At autopsy, angioinvasive mycosis was evidenced mainly in the heart, lungs, kidneys, and adrenals.

Scheduling Nodes in Underwater Networks using Voronoi Diagram

Underwater networks are used for monitoring water resources and underwater environments. Thus, it is important that the underwater sensor nodes cover the largest region possible, during the largest amount of time. This paper presents a method to perform node scheduling in underwater stratified networks. It aims to maintain the network active for longer, maintaining its connectivity. Voronoi Diagrams are used to decompose the space into regions around each node in order to determine which one should be scheduled to sleep. Simulation results show that the proposed method achieves the desired objectives, more than doubling the network lifetime while guaranteeing connectivity.

Periprostatic venous thrombosis

under the terms of the Creative Commons Attribution Non-Commercial License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium provided the article is properly cited. a Pathology and Forensic Department Faculty of Medicine Universidade Federal de Minas Gerais, Belo Horizonte/MG – Brazil. b Internal Medicine Department Faculty of Medicine Universidade Federal de Minas Gerais, Belo Horizonte/MG – Brazil. Periprostatic venous thrombosis