Complement activation and disease: protective effects of hyperbilirubinaemia.

Complement, an important effector mechanism of the immune system, is an enzymatic cascade of approx. 30 serum proteins leading to the amplification of a specific humoral response. It can be activated through the classical or alternative pathways, or through the mannose-binding lectin pathway. The activation of the classical pathway is initiated by the binding of the C1 component to antigen-bound antibodies, known as immunocomplexes. C1 is a complex of one molecule of C1q, two molecules of C1r and two molecules of C1s. C1q contains three copies of a Y-shaped fundamental unit with globular heads included in its structure, which play a major role in the interaction with the Fc portion of immunoglobulins. Deficient or exacerbated activation of the complement system leads to diseases of variable severity, and pharmacological inhibition of the complement system is considered as a therapeutic strategy to ameliorate the inflammatory effects of exacerbated complement activation. Bilirubin is a product of haem degradation by the concerted action of haem oxygenase, which converts haem into biliverdin, and biliverdin reductase, which reduces biliverdin to UCB (unconjugated bilirubin). UCB exerts both cytoprotective and cytotoxic effects in a variety of tissues and cells, acting either as an antioxidant at low concentrations or as an oxidant at high concentrations. In the present review, we describe in detail the anti-complement properties of bilirubin, occurring at levels above the UCB concentrations found in normal human serum, as a beneficial effect of potential clinical relevance. We provide evidence that UCB interferes with the interaction between C1q and immunoglobulins, thus inhibiting the initial step in the activation of complement through the classical pathway. A molecular model is proposed for the interaction between UCB and C1q.

Protective role of unconjugated bilirubin on complement-mediated hepatocytolysis.

Hyperbilirubinemia and complement-mediated immune attack on hepatocyte membrane are common features of certain hepatic diseases. To assess whether unconjugated bilirubin (UB) counteracts complement-mediated hepatocytolysis, we first generated a rabbit polyclonal antibody (Ab) against rat hepatocyte plasma membrane (RHPM). An assay performed with isolated rat hepatocytes in the presence of the polyclonal Ab and rat serum as complement donor demonstrated that UB inhibits cell lysis, as lactate dehydrogenase release into the medium was inhibited by the pigment in a dose-dependent manner. Immunofluorescence microscopy studies showed that UB significantly attenuates the binding of C3 to the hepatocyte-Ab complex. Further enzyme immunoassay studies showed that UB interferes the binding of C1q to purified anti-RHPM IgG, also in a dose-dependent manner. A dot-blot assay showed that [14C]-UB binds to C1q and human serum albumin (HSA) to a similar extent. A differential spectrum analysis of UB in the presence of C1q further confirmed that the pigment interacts with this protein. In conclusion, we demonstrated an inhibitory action of UB on complement-mediated Ab-induced hepatocytolysis, this action being evidenced at pathophysiological pigment concentrations (171 microM and higher). A direct binding of the pigment to C1q is likely involved.

[Mammary tuberculosis in AIDS patient: a case report.] / Tuberculosis mamaria en paciente con SIDA: a propósito de un caso.

Introduction: The incidence of breast tuberculosis in the world is very low. This pathology can be primary and, more commonly, secondary. It is presented as an extrapulmonary focus due to Mycobacterium tuberculosis invasion in the mammary gland. Methods: Method: we present the clinical case of a 29-year-old in AIDS woman a breast tumor. At the time of the consultation, rales were also heard in both pulmonary fields. A chest x-ray, blood analysis, and computed tomography of breast tumor and armpit, were performed. One month after admission to the hospital, the tumor fistulized and drained purulent secretion spontaneously. A sample was taken and sent to anatomopathological and microbiological analysis A tuberculin skin test (PPD) was also performed. ouch. Results: the chest X-ray showed a diffuse interstitial infiltrate, suggestive of Pneumocystis Jirovecci pneumonia. Computed tomography of the breast and armpit tumors reported the presence of multiple adenopathies. The PPD value reported was 5 millimeters; this rate is considered as a positive reaction in HIV patients. The result of the pathological anatomy for neoplasic cells was negative. The microbiological results were: Mycobacterium tuberculosis, sensitive to Isoniacid, Streptomycin, Pyrazinamide, Ethambutol and Rifampicin. Conclusion: Based on the results of the laboratory report, the diagnosis was pulmonary and mammary tuberculosis. The pulmonary tuberculosis in AIDS patients, can give non-characteristic radiographic images. This case proved how the diagnosis could be confused with pneumonia by Peumocystis jirovecci in a first appr

Introducción: la incidencia de tuberculosis mamaria en el mundo es muy baja.Esta patología puede ser primaria y más comúnmente secundaria. Se presenta como un foco extrapulmonar por invasión de Mycobacterium tuberculosis a la glándula mamaria. Métodos: presentamos el caso clínico de una mujer de 29 años con SIDA con tumoración de mama.Al momento de la consulta, también se auscultaron rales en ambos campos pulmonares.Se realizó radiografía de tórax, análisis de sangre, y tomografía computada de dicha tumoración de mama y axila.Al mes desde su ingreso al hospital, la tumoración fistulizó y drenó secreción purulenta de manera espontánea. Se tomó muestra y se envió para estudios anatomopatológico y microbiológico.También se realizó prueba de tuberculina (PPD). Resultados: la radiografía de tórax mostró un infiltrado intersticial difuso, sugestivo de neumonía por Pneumocystis Jirovecci. La tomografía computada de tumoración de mama y axila informó la presencia de múltiples adenopatías.El valor de PPD reportado fue de5 milímetros, valor considerado como reacción positiva en pacientes con VIH.El resultado de la anatomía patológica fue negativo para células neoplásicasLos resultados microbiológicos fueron: Mycobacterium tuberculosis, sensible a Isoniacida, Estreptomicina, Pirazinamida (PAS), Etambutol y Rifampicina. Conclusión: En base a los resultados del informe de laboratorio se realizó el diagnóstico de tuberculosis pulmonar, ganglionar y mamaria. La tuberculosis pulmonar en pacientes con SIDA, puede dar imágenes radiográficas no características, como en este caso que fue confundido en un primer momento con neumonía por Peumocystis Jirovecci.

Estimating the likelihood of success with the initial empiric antimicrobial therapy in patients with nosocomial infections.

In order to estimate the likelihood of success (SL) with the initial empiric antimicrobial therapy, the following formula was constructed with data subjected to prior clinical validation in real time: SL (%) = (Nº isolates susceptible to IEAT/Nº patients with MDI) × 100. Where the numerator of the formula represents the total number of isolates recovered from the assessed type of infection, that was susceptible to any component of empiric antimicrobial therapy (IEAT) used, and the denominator represents the total number of patients with the same assessed, but microbiologically documented infection (MDI). For male hospital-acquired urinary tract infection, only imipenem reached a suitable SL value (i.e. ≥80%). In patients with hospital-acquired peritonitis, imipenem and tigecycline-ceftazidime showed the highest coverage rates. For ventilator-associated pneumonia only imipenem yielded acceptable coverage as a single drug. Implementing the present formula instead of the regular global antibiograms used to guide the selection of the initial treatment may benefit the patient outcome and improve antimicrobial usage.

In vivo anti-complement effect of bilirubin-IXalpha.

The effect of the IXalpha isomer of unconjugated bilirubin (UB) on complement-mediated intravascular hemolysis was evaluated in rats carrying naturally occurring heteroantibodies against sheep erythrocytes. Several doses of UB were administered i.v. to these animals in order to induce different levels of hyperbilirubinemia. Intravascular hemolysis was promoted by transfusion with a sheep red cell suspension. Hemoglobin in urine was assessed as a marker of intravascular hemolysis. The urinary excretion of hemoglobin was attenuated by UB in a dose-dependent manner. To establish whether complement was involved in the hemolytic reaction, we evaluated the hemolytic activity of complement in these same animals, before and after sheep erythrocyte transfusion. The significant consumption of complement, which was partially prevented by UB, corroborated its participation in the intravascular hemolytic reaction in the current experimental conditions. The data suggest an inhibitory action of UB on complement-mediated hemolysis in vivo.

Evaluation of urinary N-acetyl-beta-D-glucosaminidase as a marker of early renal damage in patients with type 2 diabetes mellitus.

OBJECTIVE: To evaluate the clinical usefulness of urinary N-acetyl-beta-D-glucosaminidase (NAG) excretion for the detection of early tubular damage in type 2 diabetes mellitus (T2DM). SUBJECTS AND METHODS: Thirty six patients with T2DM were divided into two groups based on urinary albumin to creatinine ratio (ACR): normoalbuminuria (ACR <30 mg/g; n=19) and microalbuminuria (ACR =30-300 mg/g; n=17). The following parameters were determined in both groups: urinary NAG and albumin, serum and urine creatinine, fasting plasma glucose and glycated hemoglobin (HbA1c). RESULTS: Urinary NAG levels [Units/g creatinine; median (range)] were significantly increased in microalbuminuria group [17.0 (5.9 - 23.3)] compared to normoalbuminuria group [4.4 (1.5 - 9.2)] (P<0.001). No differences between groups were observed in fasting glucose, HbA1c, serum creatinine levels and estimated glomerular filtration rates (eGFR). Urinary NAG positively correlated with ACR (r=0.628; p<0.0001), while no significant association was observed between NAG and glycemia, HbA1c, serum creatinine and eGFR. CONCLUSIONS: The increase of urinary NAG at the microalbuminuria stage of diabetic nephropathy (DN) suggests that tubular dysfunction is already present in this period. The significant positive association between urinary NAG excretion and ACR indicates the possible clinical application of urinary NAG as a complementary marker for early detection of DN in T2DM.

Unconjugated bilirubin inhibits C1 esterase activity.

OBJECTIVE: To evaluate if unconjugated bilirubin (UB) inhibits C1 esterase activity. DESIGN AND METHODS: Esterase activity was evaluated by C1-mediated hydrolysis of N-acetyl-L-tyrosine ethyl ester, and binding of UB to C1r and C1s was assessed by dot-blot analysis. RESULTS: UB inhibited C1 enzymatic activity. C1r, C1s and human serum albumin bound [(14)C]-UB to a similar extent. CONCLUSIONS: UB inhibits C1 esterase activity, apparently due to a direct pigment-protein interaction. This could explain the inhibitory action of UB on complement activation.

Evaluation of urinary N-acetyl-beta-D-glucosaminidase as a marker of early renal damage in patients with type 2 diabetes mellitus / Avaliação da N-acetil-beta-D-glucosaminidase urinária como marcador de dano renal precoce em pacientes com diabetes melito tipo 2

Objective To evaluate the clinical usefulness of urinary N-acetyl-beta-D-glucosaminidase (NAG) excretion for the detection of early tubular damage in type 2 diabetes mellitus (T2DM). Subjects and methods Thirty six patients with T2DM were divided into two groups based on urinary albumin to creatinine ratio (ACR): normoalbuminuria (ACR <30 mg/g; n=19) and microalbuminuria (ACR =30‐300 mg/g; n=17). The following parameters were determined in both groups: urinary NAG and albumin, serum and urine creatinine, fasting plasma glucose and glycated hemoglobin (HbA1c). Results Urinary NAG levels [Units/g creatinine; median (range)] were significantly increased in microalbuminuria group [17.0 (5.9 - 23.3)] compared to normoalbuminuria group [4.4 (1.5 - 9.2)] (P<0.001). No differences between groups were observed in fasting glucose, HbA1c, serum creatinine levels and estimated glomerular filtration rates (eGFR). Urinary NAG positively correlated with ACR (r=0.628; p<0.0001), while no significant association was observed between NAG and glycemia, HbA1c, serum creatinine and eGFR. Conclusions The increase of urinary NAG at the microalbuminuria stage of diabetic nephropathy (DN) suggests that tubular dysfunction is already present in this period. The significant positive association between urinary NAG excretion and ACR indicates the possible clinical application of urinary NAG as a complementary marker for early detection of DN in T2DM. .

Objetivo Avaliar a utilidade clínica da excreção urinária da N-acetil-beta-D-glucosaminidase (NAG) para a detecção de dano tubular precoce no diabetes melito tipo 2 (DM2). Sujeitos e métodos Foram estudados trinta e seis pacientes com DM2 que se dividiram em dois grupos com base na excreção urinária de albumina (EUA): normoalbuminúrico (EUA <30 mg/g de creatinina; n=19) e microalbuminúrico (EUA =30‐300 mg/g de creatinina; n=17). Em ambos os grupos foram determinados os seguintes parâmetros: NAG e albumina urinária, creatinina sérica e urinária, glicemia de jejum e hemoglobina glicada (HbA1c). Resultados Os níveis de NAG urinária [unidades/g de creatinina; mediana (intervalo interquartílico)] foram significativamente maiores no grupo microalbuminúrico [17,0 (5,9 - 23,3)] em comparação com o grupo normoalbuminúrico [4,4 (1,5 - 9,2)] (p<0,001). Não se observaram diferenças significativas entre os dois grupos nos níveis de glicemia de jejum, HbA1c, creatinina sérica e taxa de filtração glomerular estimada (TFGe). A NAG urinária se correlacionou positivamente com o EUA (r=0,628, p<0,0001), não sendo observada associação significativa da NAG com glicemia, HbA1c, creatinina sérica e TFGe. Conclusões O aumento da NAG urinária na fase de microalbuminúria da nefropatia diabética (ND) sugere que a disfunção tubular já está presente nesse período. A associação positiva significativa entre a excreção urinária da NAG e EUA indica a possível aplicação clínica da NAG urinária como marcador complementar para a detecção precoce da ND no DM2. .

Anticuerpos anti-anexina V y otros marcadores de actividad antifosfolip¨ªdica en mujeres abortadoras recurrentes con enfermedades autoinmunes / Anti-annexi V antibodies and other markers of antiphospholipid activity in women with recurrent miscarriage with autoinmune diseases

Los anticuerpos (Ac) antifosfolip¨ªdicos componen una familia de auto Ac involucrada en eventos tromb¨®ticos que participar¨ªan de la actividad antifosfolip¨ªdica (AAF). La probabilidad de aborto en una paciente con estos Ac es del 91%. Se ha sugerido la existencia de un nuevo cofactor: la anexina V, altamente expresada en el sinciciotrofoblasto placentario, originando Ac que podr¨ªan estar implicados en las p¨¦rdidas fetales recurrentes. Nuestro objetivo fue analizar la asociaci¨®n entre los Ac anti-anexina V y otros indicadores de AAF [anticardiolipina(ACA), anti-¦Â2 glicoprote¨ªna 1 (a-¦Â2GP1) o anticoagulante l¨²pico (AL)] en mujeres con enfermedades autoinmunes y repetidas p¨¦rdidas fetales. Se incluyeron 25 mujeres abortadoras recurrentes con lupus eritematoso sist¨¦mico y/o s¨ªndrome antifosfolip¨ªdico (A) y un grupo control de 33 mujeres con las patolog¨ªas mencionadas anteriormente, no abortadoras (NA). Se determinaron los niveles de anti-anexina V, ACA y de a-¦Â2GP1 por ELISA. El AL se evidenci¨® con pruebas de screening y confirmatorias. El 96% del grupo A present¨® AAF positiva y el 4% niveles elevados de Ac a-anexina V. El grupo NA mostr¨® AAF en el 70% de los casos y niveles elevados de Ac a-anexina V en un 3%. Se puede concluir que no existe asociaci¨®n entre Ac anti-anexina V y los indicadores de AAF.

[Spermatic fertilization capacity after swim-up spermatozoa recovery technique]. / Capacidad fecundante espermática luego de la recuperación de espermatozoides mediante la técnica de swim-up.

OBJECTIVES: To investigate sperm quality before and after swim up in infertile patients, and to compare it with a fertile men population. METHODS: Semen samples from 55 patients consulting at the infertility services of the Hospitals "Centenario" in Rosario and "Eva Perón" in Gro Baigorria were collected and analyzed accordingly with the WHO guidelines. 30 sperm samples with a volume higher than 1.0 ml, and spermatozoid concentration higher than 5,000,000/ml, not presenting hyperviscosity were selected. Outcome variables including progressive mobility (PM), morphology (M), chromatin condensation (CC) and chromatin integrity (CIl, were compared in fresh semen samples, between patients without previous treatment (G2) and after swim up (G3) and 15 fertile men (G1). Sperm morphology was evaluated by brilliant green hematoxyllin stain; progressive mobility with a subjective method accordingly to WHO (1999); chromatin condensation with aniline blue test; and chromatin integrity with acridine orange as fluorocrom. Swim up technique was based on Berger et al. ( 1985) with mHTF, heatingthe samples in a Falcon tube in a 45 degree angle in a 37 degree C gas heater for one hour (5% CO2 atmosphere). Following incubation 0.5 ml of the overlay containing sperm cells that swam up from the pellet were removed to process the recovered spermatozoids. Student's t test was applied to compare PM, M, CC, and CI between the four groups. A significant difference was found between G1 vs G3 and G2 vs G3 (p < 0.001). No significant differences were found between G1 and G3 (p > 0.1). It showed that PM, M, CC and C1 parameters in the recovered spermatozoids after swim up were similar to fertile population. CONCLUSIONS: Our results indicate that through the swim up procedure gametes with fertile ability similar to normal fertile population can be recovered to be applied in low complexity in vitro fertilization techniques such as intrauterine insemination, where the natural selection is still viable.