Ultrastructural Study of the Peritoneum in Patients on Continuous Ambulatory Peritoneal Dialysis

Twenty peritoneal specimens, collected from 19 patients at the insertion or removal of the catheter for continuous ambulatory peritoneal dialysis (CAPD), were examined by light microscopy (LM) and transmission and scanning electron microscopy (TEM and SEM). During long-term CAPD, the peritoneal tissue showed an absence of mesothelial cells and a fibrous thickening by proliferation of degenerative collagen fibers. Ultrastructural examination by SEM revealed that the surface of the peritoneum with mesothelial denudation was covered by a continuous sheet of homogeneous material (a membrane structure) in patients in an the early stage of peritonitis. In cases in the advanced stage, the membrane structure covered the irregular collagen bundles, which occasionally showed through breaks in the membrane-like structure. Vascular alterations characterized by the hyalinous degeneration of media, the thickening of the basement membrane in small vasculature, and lymphatic dilatation were observed by TEM in cases of sclerosing peritonitis. Our results suggest that the pathological changes of the peritoneal surface and peripheral blood and lymphatic circulatory impairment may be related to ultrafiltration failure and the progression of pathological process during CAPD

Ultrastructural Study of the Peritoneum in Patients on Continuous Ambulatory Peritoneal Dialysis

Twenty peritoneal specimens, collected from 19 patients at the insertion or removal of the catheter for continuous ambulatory peritoneal dialysis (CAPD), were examined by light microscopy (LM) and transmission and scanning electron microscopy (TEM and SEM). During long-term CAPD, the peritoneal tissue showed an absence of mesothelial cells and a fibrous thickening by proliferation of degenerative collagen fibers. Ultrastructural examination by SEM revealed that the surface of the peritoneum with mesothelial denudation was covered by a continuous sheet of homogeneous material (a membrane structure) in patients in an the early stage of peritonitis. In cases in the advanced stage, the membrane structure covered the irregular collagen bundles, which occasionally showed through breaks in the membrane-like structure. Vascular alterations characterized by the hyalinous degeneration of media, the thickening of the basement membrane in small vasculature, and lymphatic dilatation were observed by TEM in cases of sclerosing peritonitis. Our results suggest that the pathological changes of the peritoneal surface and peripheral blood and lymphatic circulatory impairment may be related to ultrafiltration failure and the progression of pathological process during CAPD

Estratégias de automação para desenvolvimento de projetos de sistemas embarcados baseados em modelos formais de computação

Orientador: Denis SIlva LoubachDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia MecânicaResumo: Sistemas embarcados de alta performance estão presentes em cada vez mais áreas de aplicação. Com o aumento da complexidade, se torna mais difícil atender ao requisito de se projetar o sistema mais otimizado utilizando menos recursos. Nesse contexto, os métodos de projeto de sistemas embarcados baseados em modelos formais têm sido estudados para tornar esse processo mais robusto e escalável. O uso de modelos de computação (MoC), que consistem na modelagem de uma aplicação utilizando um alto nível de abstração com base formal, possibilita uma análise sistemática do sistema antes de sua implementação. Ferramentas e frameworks têm sido desenvolvidos para a modelagem baseada em MoCs. Algumas dessas ferramentas suportam a simulação dos modelos, possibilitando a verificação das funcionalidades do sistema antes das próximas fases do projeto. O aumento do nível de abstração, proporcionado pelo uso dos MoCs, dificulta a fase de implementação pela falta de detalhes nos modelos de alto nível de abstração. Nesse sentido, esta pesquisa tem como objetivo identificar possíveis estratégias de automação para o desenvolvimento de sistemas embarcados baseado em modelos formais de computaçãoAbstract: Sophisticated and high performance embedded systems are present in an increasing number of application domains. As the complexity grows, it gets harder to satisfy the requirement of getting the most optimized system using less development resources. In this context, formal-based design methods have been studied to make the development process robust and scalable, using the correct-by-construction approach. Models of computation (MoC), which consists on modeling an application at a high abstraction level by using a formal base, enables a systematic application analysis before its implementation. Different tools and frameworks have been developed supporting MoCs. Some of them can simulate the models and also verify its functionality and feasibility before the next design steps. As MoC elevates the abstraction level, the implementation steps get more complex, creating an abstraction gap. In view of this, the present research aims to identify possible automation approaches for embedded systems design flowsMestradoMecatrônicaMestre em Engenharia Mecânic

Severity of Glomerulosclerosis Predicts Prognosis of IgA Nephropathy with Proteinuria

We determined the natural history of IgA nephropathy (IgAN) among patients who presented with proteinuria, and factors associated with the development of clinical events, namely blood pressure(BP)竕ｧ130/85 mmHg, serum creatinine 竕ｧ1.4mg/dl. We analyzed data from 16 patients(mean age 35 ﾂｱ 14 years) with IgAN accompanied by proteinuria between 1990 and 1998. We also semiquantified scores of glomerulosclerosis (GS), tubulointerstitial damage (TID), hyaline arteriosclerosis (HA), and IgAN classification. The median duration of follow-up was 48 months. During clinical follow-up, seven (44%) patients became hypertensive, among who five (31%) developed impaired renal function and two (13%) progressed to treatment with hemodialysis. Events did not develop in the other 9 patients (56%). Clinical findings were not significantly different between the events and event-free groups. The GS and TID scores revealed significant differences between patient groups. Only the renal histological parameters of GS and events were statistically correlated with renal survival. We conclude that the severity of GS may be the important prognostic factor inpatients with IgAN accompanied by proteinuria at the time of the initial biopsy

Renal Outcome of Immunoglobulin A Nephropathy With Mild Proteinuria

We determined the natural history of immunoglobulin A nephropathy (IgAN) among patients who presented with mild proteinuria (0.2 to 0.4 g/day), and factors associated with development of adverse clinical events, defined as proteinuria 竕ｧ 1.0g/day, blood pressure > 130/80mmHg, serum creatinine 竕ｧ 1.4mg/dl. We did analyzed data from 27 patients(mean age 30 ﾂｱ 12 years) with IgAN accompanied by mild proteinuria between 1990 and 1998. We also evaluated semiquantitave scores of glomerulosclerosis, tubulointerstitial injury, hyaline arteriosclerosis, and IgAN classification. The median duration of follow-up was 51 months. During followup, at least one adverse clinical event affected 15 patients (56%): among who eight (53%) developed proteinuria. And one of 8 developed impaired renal function and 7 (47%) became hypertensive. Another 12 patients (44%) were not affected by adverse clinical events. The clinical findings were not significantly different between the adverse events and no evens group. The scores of glomerulosclerosis and tubulointerstitial injury reveled significant differences between events. The only renal histological parameters of glomerulosclerosis and adverse clinical events were statistically correlated with renal survival. We concluded that IgAN with mild proteinuria frequently follows a slow by progressive course and that the severity of glomerulosclerosis may be predictable prognostic factor in patients who have IgAN with by mild proteinuria

Usefulness of Transdermal Glyceryl Trinitrate for Radial Arterial Spasm on Arteriovenous Hemodialysis Fistula Operation in Uremic Patients

Vasospasm sometimes disturbs successful blood access for hemodialysis, and prevention of vasospasm is desirable when constructing arteriovenous fistulae. We first investigated vasospasm of the radial artery in this operation and analyzed factors associated with this phenomenon in 20 patients with end-stage renal disease. Alteration of blood flow in the radial artery was evaluated in them, and intima-media thickness (IMT), endothelial function index (EFI) and laboratory data were analyzed. Vasospasm occurred in 9 of 20 cases (45.0%) at 5 min after anastomosis, and displayed a marginally significant correlation (r=0.31, p=0.081) with EFI. We then conducted a randomized study of 84 patients with end-stage renal disease to examine the effects of administering transdermal glyceryl trinitrate (GTN) in this operation. EFI was significantly correlated with IMT (r= -0.45, p<0.001). At 5 min after anastomosis, vasospasm occurred in 12 (28.6%) of 42 patients who were administered GTN, while it occurred in 20 (47.6%) of 42 patients without GTN administration (controls); the difference was marginally significant (p=0.072). In patients with IMT?1.1, alteration of diameter (5 min/1 min after anastomosis) was significantly reduced compared with controls (p=0.032). These data suggest that IMT could offer a predictor of vasospasm occurrence during arteriovenous fistula operations. Use of preoperative transdermal GTN may be effective in preventing vasospasm during such surgery