Marcos Cezar Feitosa de Paula Machado

Digital image analysis of skin neoplasms evaluated by lectin histochemistry: potential marker to biochemical alterations and tumour differential diagnosis

The present study aims to evaluate, through lectin histochemistry, the alterations in the expression of cell surface carbohydrate between benign and malignant lesions of skin using computer image analysis. Skin fragments were obtained through biopsies and diagnosed as basal cell carcinoma (BCC), epidermoid carcinoma (EpC), trichoepithelioma (TE), keratoacanthoma (KA), seborrheic keratosis (SK) and actinic keratosis (AK). Lectins Con A, WGA, PNA, UEA-I and LTA were used in histochemistry study. Image analysis was carried out in a workstation using OPTIMASTM software system. PNA strong binding pattern to studied tumours evidenced the high expression of D-galactose residues in the epidermal neoplasms when compared to other sugars recognized by the other lectins. Among benign neoplasms, KA presented a high expression of glucose/mannose, a-fucose and D-galactose residues evidenced by the intense staining of Con A (94.7%), LTA (84.2%) and PNA (89.4%), respectively. Malignant tumours showed distinct binding patterns. EpC presented significant binding only by PNA lectin. BCC was differentially stained in comparison to the staining pattern observed in benign lesions such as TE. Qualitative (lectin histochemistry) and quantitative (digital image analysis) data obtained in this study evidenced those lectins are potential markers to biochemical alterations in skin neoplasms.

Hipertensão porta na esquistossomose mansônica: repercussões do tratamento cirúrgico no perfil histomorfométrico da mucosa gástrica

The repercussions from surgical treatment for controlling portal hypertension and its effects on the gastric vasculature of young patients with mansonic schistosomiasis were investigated by digital image analysis. The study included five patients at the preoperative stage and 27 patients who had undergone surgical intervention at different times in the past: 0-2 years ago, n=4; 2-6 years ago, n=13, and more than 6 years ago, n=10. Endoscopic biopsies were taken from the mucosa of the gastric antrum and body endoscopic mucosa and the samples underwent routine histological tests after embedding in paraffin blocks. Histological thin sections were used for histomorphometric analysis of the following parameters: mean number of vessels per field, and mean diameter and thickness of the vessel walls. The results showed that, between the patients whose operation was not more than two years ago and those whose operation was more than six years ago, there was a significant decrease in the density and diameter of the vessels. These findings give support to the concept that the surgical treatment administered decreases specific histological alterations like hemorrhage and ectasia, over the long term.: The repercussions from surgical treatment for controlling portal hypertension and its effects on the gastric vasculature of young patients with mansonic schistosomiasis were investigated by digital image analysis. The study included five patients at the preoperative stage and 27 patients who had undergone surgical intervention at different times in the past: 0-2 years ago, n=4; 2-6 years ago, n=13, and more than 6 years ago, n=10. Endoscopic biopsies were taken from the mucosa of the gastric antrum and body endoscopic mucosa and the samples underwent routine histological tests after embedding in paraffin blocks. Histological thin sections were used for histomorphometric analysis of the following parameters: mean number of vessels per field, and mean diameter and thickness of the vessel walls. The results showed that, between the patients whose operation was not more than two years ago and those whose operation was more than six years ago, there was a significant decrease in the density and diameter of the vessels. These findings give support to the concept that the surgical treatment administered decreases specific histological alterations like hemorrhage and ectasia, over the long term.

Galectina-3 em tumores de próstata: imuno-histoquímica e análise digital de imagens

Immunohistochemistry helps pathologists in the diagnosis of prostatic diseases, mainly carcinomas. Equally important, digital image analysis is being increasingly used to study alterations in the prostate. The present work aims to morphometrically quantify the immunostain of galectin-3 expressed in normal prostate (NP), benign hyperplasia (BH) and prostatic adenocarcinoma (PA) in humans. Immunohistochemistry was developed using monoclonal anti-galectin-3 antibody. Surgical specimens from different patients with BH (n = 12), PA (n = 10) and NP (n = 10) were fixed in formalin, processed and embedded in paraffin. Hematoxylin and eosin staining was used to confirm the diagnosis. Tissue slices (4µm) were incubated with anti-galectin-3 antibody solution for one hour at room temperature and then incubated with a secondary anti-body conjugated to peroxidase (30 minutes). The stain pattern was visualized with diaminobenzidine (DAB) and hydrogen peroxide. Image analysis was carried out using a workstation consisting of a standard light microscope equipped with a digitalizing camera connected to a desktop personal computer. Image storage and retrieval was managed using the OPTIMAS® software system. For prostatic adenocarcinoma cells a significant decreased (p < 0.001) staining pattern for galectin-3 was observed. Computer image analysis detected stained areas of atypic prostatic cells: BH (875.9 ± 52.1µm2), PA (120.2 ± 23.3µm2) and NP (238.4 ± 27.6µm2). The different patterns of galectin-3 expression distinguished the neoplasic cells from normal prostatic ones and significant alterations in the galectin-3 expression into the studied tumor lesions.

Prototyping a high availability PaaS: Performance analysis and lessons learned

With cloud computing consolidation, Platform-as-a-Service (PaaS) has been used as a solution for developing applications with low cost and maximum flexibility. However, an open challenge related to PaaS is the proper handling of multi-tier and stateful applications with support for high availability (HA); and scalability can be considered an essential feature for HA. However, dealing with several instances of the same application that access its state in a common area is not a simple task. This paper presents a novel PaaS framework, named NoPaaS, that supports the deployment of multi-tier and stateful applications assuring their availability according to the Service Availability Forum (SAF) redundancy model. The primary goal of this work is to present NoPaaS framework and prototype, and highlight challenges and open issues when providing multi-tier and stateful applications in high availability clouds.

A Network Access Control solution combining OrBAC and SDN

Standard Port-based Network Access Control (NAS) with tagged Virtual Local Area Networks (VLANs) systems are useful to authenticate users within an isolated network environment. This approach on its own, however, lacks the flexibility and granularity level that new generation networks based on SDN (Software Defined Networking) can provide. The flow-based access control provides a more appropriate granularity to enforce network policies. In this paper, we propose a novel solution named SDN-based Network Access Control (S-NAC) that provides authentication and authorization of clients and servers based on high-level policies enforced at flow level. The solution has been implemented, deployed and tested over emulated and real networks.

Adopting security routines in legacy organizations

Security is a well-known critical issue and exploitation of vulnerabilities is increasing in number, sophistication and damage. Furthermore, legacy systems tend to offer difficulty when upgrades are needed, specially when security recommendations are proposed. This paper presents a strategy for legacy systems based on three disciplines which guide the adoption of secure routines while avoid production drop. We present a prototype framework and discuss its success in providing security to the network of a power plant.