Proteinúria: avaliação clínica e laboratorial

Proteinuria is a strong indicator of renal disease and it is present in many syndromes. Our objective is to review the pathophysiological mechanisms that lead to proteinuria, as well as the available methods for its detection and quantitation, including the dipstick, 24-hour proteinuria, and the urinary protein-creatinine ratio. We gave special attention to clinical evaluation of proteinuric patients, including the available exams and the situations in which they are indicated. An algorithm for the investigation of patients with proteinuria is presented. We also emphasized the importance of persistent proteinuria in its relation with the progression of renal diseases.Proteinúria é um forte indicador de doença renal, e está presente em diversas síndromes. No presente artigo, os mecanismos fisiopatológicos que levam à proteinúria foram revisados, assim como os métodos disponíveis para sua detecção e quantificação, incluindo a fita reagente, proteinúria de 24 horas e o índice proteína/creatinina na urina. Atenção especial é dada à avaliação clínica dos pacientes com proteinúria, abordando os exames disponíveis e as situações em que são indicados. Um fluxograma para a investigação de pacientes com proteinúria é apresentado. Também ressaltamos a importância da proteinúria persistente na sua relação com a progressão de doenças renai

Tratamento da nefropatia lúpica severa: efeito da ciclofosfamida endovenosa prolongada e intermitente

OBJECTIVE: Intravenous cyclophosphamide is widely used in the treatment of lupus nephritis. In order to analyze long-term outcome in patients with severe lupus nephritis, we studied 54 patients treated with cyclophosphamide at our services between 1989 and 1999. MATERIALS AND METHODS: Our study included 42 patients. According to World Health Organization classification, the initial renal biopsy indicated lupus nephritis class III in 16.7% patients and class IV in 83.3%. The average serum creatinine and proteinuria at the beginning of treatment were, respectively 3.1 ± 2.5 mg/dl and 7.2 ± 5.4 g/24h/1.73m2. Eighty-eight percent of patients had nephrotic range proteinuria and 83.3% had serum creatinine levels higher than 1.2mg/dl. The mean duration of nephritis before treatment was 10 months; however, in 52% of patients it was less than 6 months. Average follow-up time from the beginning of treatment to outcome (end-stage renal disease or death) was 72.2 ± 36.3 months. Patients received immunosuppressive therapy according to the National Institutes of Health protocol and were classified, according to clinical and laboratory response into complete remission, partial remission, or treatment failure. RESULTS: Total or partial remission was achieved in 70% of patients by the end of the first year; 62.5 % of patients were kept in remission up to the third year. The 3, 5, and 10-year actuarial renal survival rates were of 90.2%, 90.2%, and 77.67%, respectively. One patient died and 5 had to start hemodialysis. The adverse effects of immunosuppression were respiratory infection (19.0%), Herpes Zoster (7.1%), temporary (9.5%) and permanent (2.3%) amenorrhea, avascular necrosis of the femoral head (4.7%), and sepsis (2.3%). Neither hemorrhagic cystitis nor neoplasia were observed during follow-up. CONCLUSIONS: We concluded that intravenous cyclophosphamide was effective in the control of acute lupus nephritis and in the maintenance of long-term renal function without serious adverse events. OBJETIVOS: A ciclofosfamida intravenosa é amplamente usada no tratamento da nefrite lúpica. Para analisar os desfechos a longo prazo, estudamos 54 pacientes tratados com ciclofosfamida no período compreendido entre 1989 e 1999. MATERIAIS E MÉTODOS: Quarenta e dois pacientes foram incluídos no estudo. As biópsias renais revelaram, de acordo com a classificação da Organização Mundial de Saúde, nefrite lúpica classe III em 16,7% dos pacientes e classe IV em 83,3%. No início do tratamento, médias de creatinina sérica e proteinúria foram, respectivamente de 3,1 ± 2,5 mg/dl e 7,2 ± 5,4g/24h/1.73m2. Oitenta e oito por cento dos pacientes tinham proteinúria nefrótica, e em 83,3% a creatinina sérica era maior que 1,2 mg/dl. A duração média da nefrite anterior ao tratamento era de 10 meses, porém em 52% dos pacientes a duração era inferior a 6 meses. O seguimento médio desde o início do tratamento até os desfechos avaliados (insuficiência renal crônica terminal ou morte) foi de 72,2 ± 36,3 meses. Os pacientes receberam tratamento imunossupressor de acordo com o protocolo do National Institutes of Health dos Estados Unidos. Os pacientes foram classificados de acordo com a resposta clínico-laboratorial em remissãocompleta, remissão parcial ou falha do tratamento. RESULTADOS: Remissão total ou parcial foi alcançada em 70% dos pacientes no final do primeiro ano, e 62,5 % se mantiveram em remissão no final do terceiro ano. A sobrevida renal atuarial no 3º, 5º e 10º anos foram de 90,2%, 90,2% e 77,67%, respectivamente. Um paciente evoluiu para óbito e cinco necessitaram iniciar hemodiálise. Efeitos adversos do tratamento imunossupressor foram infecção respiratória (19,0%), Herpes Zoster (7,1%), amenorréia transitória (9,5%) e permanente (2,3%), necrose avascular de fêmur (4,7%) e sepse (2,3%). No período de seguimento não foi observada a ocorrência de cistite hemorrágica ou neoplasia. CONCLUSÕES: Concluímos que ciclofosfamida endovenosa foi efetiva no controle da nefrite lúpica aguda e na manutenção da função renal a longo prazo, sem a ocorrência de efeitos adversos sérios

Proteinuria : clinical and laboratory approach

Proteinúria é um forte indicador de doença renal, e está presente em diversas síndromes. No presente artigo, os mecanismos fisiopatológicos que levam à proteinúria foram revisados, assim como os métodos disponíveis para sua detecção e quantificação, incluindo a fita reagente, proteinúria de 24 horas e o índice proteína/creatinina na urina. Atenção especial é dada à avaliação clínica dos pacientes com proteinúria, abordando os exames disponíveis e as situações em que são indicados. Um fluxograma para a investigação de pacientes com proteinúria é apresentado. Também ressaltamos a importância da proteinúria persistente na sua relação com a progressão de doenças renais.Proteinuria is a strong indicator of renal disease and it is present in many syndromes. Our objective is to review the pathophysiological mechanisms that lead to proteinuria, as well as the available methods for its detection and quantitation, including the dipstick, 24-hour proteinuria, and the urinary protein-creatinine ratio. We gave special attention to clinical evaluation of proteinuric patients, including the available exams and the situations in which they are indicated. An algorithm for the investigation of patients with proteinuria is presented. We also emphasized the importance of persistent proteinuria in its relation with the progression of renal diseases

Pharmaceutical Characterization of MyoNovin, a Novel Skeletal Muscle Regenerator: in silico, in vitro and in vivo Studies.

MyoNovin is a novel skeletal muscle-regenerating compound developed through synthesis of two nitro groups onto a guaifenesin backbone to deliver nitric oxide to skeletal muscle with a potential to treat muscle atrophy. The purpose of this study was to utilize in silico, in vitro, and in vivo approaches to characterize MyoNovin and examine its safety, biodistribution, and feasibility for drug delivery. In silico software packages were used to predict the physicochemical and biopharmaceutical properties of MyoNovin. In vitro cardiotoxicity was assessed using human cardiomyocytes (RL-14) while effects on CYP3A4 metabolic enzyme and antioxidant activity were examined using commercial kits. A novel HPLC assay was developed to measure MyoNovin concentration in serum, and delineate initial pharmacokinetic and acute toxicity after intravenous administration (20 mg/kg) to male Sprague-Dawley rats. MyoNovin showed relatively high lipophilicity with a LogP value of 3.49, a 20-fold higher skin permeability (19.89 cm/s*107) compared to guaifenesin (0.66 cm/s*107), and ~10-fold higher effective jejunal permeability (2.24 cm/s*104) compared to guaifenesin (0.26 cm/s*104). In vitro, MyoNovinwas not cytotoxic to cardiomyocytes at concentrations below 8 μM and did not inhibit CYP3A4 or show antioxidant activity. In vivo, MyoNovin had a short half-life (t1/2) of 0.16 h, and a volume of distribution Vss of 0.62 L/kg. Biomarkers of MyoNovincardiac and renal toxicity did not differ significantly from baseline control levels. The predicted high lipophilicity and skin permeability of MyoNovin render it a potential candidate for transdermal administration while its favourable intestinal permeation suggests it may be suitable for oral administration. Pharmacokinetics following IV administration of MyoNovin were delineated for the first time in a rat model. Preliminary single 20 mg/kg dose assessment of MyoNovin suggest no influenceon cardiac troponin or β-N-Acetylglucosaminidase. This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For Readers") may comment by clicking on ABSTRACT on the issue's contents page

Self-dual noncommutative \phi^4-theory in four dimensions is a non-perturbatively solvable and non-trivial quantum field theory

We study quartic matrix models with partition function Z[E,J]=\int dM \exp(trace(JM-EM^2-(\lambda/4)M^4)). The integral is over the space of Hermitean NxN-matrices, the external matrix E encodes the dynamics, \lambda>0 is a scalar coupling constant and the matrix J is used to generate correlation functions. For E not a multiple of the identity matrix, we prove a universal algebraic recursion formula which gives all higher correlation functions in terms of the 2-point function and the distinct eigenvalues of E. The 2-point function itself satisfies a closed non-linear equation which must be solved case by case for given E. These results imply that if the 2-point function of a quartic matrix model is renormalisable by mass and wavefunction renormalisation, then the entire model is renormalisable and has vanishing \beta-function. As main application we prove that Euclidean \phi^4-quantum field theory on four-dimensional Moyal space with harmonic propagation, taken at its self-duality point and in the infinite volume limit, is exactly solvable and non-trivial. This model is a quartic matrix model, where E has for N->\infty the same spectrum as the Laplace operator in 4 dimensions. Using the theory of singular integral equations of Carleman type we compute (for N->\infty and after renormalisation of E,\lambda) the free energy density (1/volume)\log(Z[E,J]/Z[E,0]) exactly in terms of the solution of a non-linear integral equation. Existence of a solution is proved via the Schauder fixed point theorem. The derivation of the non-linear integral equation relies on an assumption which we verified numerically for coupling constants 0<\lambda\leq (1/\pi).Comment: LaTeX, 64 pages, xypic figures. v4: We prove that recursion formulae and vanishing of \beta-function hold for general quartic matrix models. v3: We add the existence proof for a solution of the non-linear integral equation. A rescaling of matrix indices was necessary. v2: We provide Schwinger-Dyson equations for all correlation functions and prove an algebraic recursion formula for their solutio