COVID-19-associated acute kidney injury patients treated with renal replacement therapy in the intensive care unit: A multicenter study in São Paulo, Brazil.

INTRODUCTION: Multicenter studies involving patients with acute kidney injury (AKI) associated with the disease caused by the new coronavirus (COVID-19) and treated with renal replacement therapy (RRT) in developing countries are scarce. The objectives of this study were to evaluate the demographic profile, clinical picture, risk factors for mortality, and outcomes of critically ill patients with AKI requiring dialysis (AKI-RRT) and with COVID-19 in the megalopolis of São Paulo, Brazil. METHODS: This multicenter, retrospective, observational study was conducted in the intensive care units of 13 public and private hospitals in the metropolitan region of the municipality of São Paulo. Patients hospitalized in an intensive care unit, aged ≥ 18 years, and treated with RRT due to COVID-19-associated AKI were included. RESULTS: The study group consisted of 375 patients (age 64.1 years, 68.8% male). Most (62.1%) had two or more comorbidities: 68.8%, arterial hypertension; 45.3%, diabetes; 36.3%, anemia; 30.9%, obesity; 18.7%, chronic kidney disease; 15.7%, coronary artery disease; 10.4%, heart failure; and 8.5%, chronic obstructive pulmonary disease. Death occurred in 72.5% of the study population (272 patients). Among the 103 survivors, 22.3% (23 patients) were discharged on RRT. In a multiple regression analysis, the independent factors associated with death were the number of organ dysfunctions at admission and RRT efficiency. CONCLUSION: AKI-RRT associated with COVID-19 occurred in patients with an elevated burden of comorbidities and was associated with high mortality (72.5%). The number of organ dysfunctions during hospitalization and RRT efficiency were independent factors associated with mortality. A meaningful portion of survivors was discharged while dependent on RRT (22.3%).

COVID-19-associated acute kidney injury patients treated with renal replacement therapy in the intensive care unit: A multicenter study in São Paulo, Brazil

INTRODUCTION: Multicenter studies involving patients with acute kidney injury (AKI) associated with the disease caused by the new coronavirus (COVID-19) and treated with renal replacement therapy (RRT) in developing countries are scarce. The objectives of this study were to evaluate the demographic profile, clinical picture, risk factors for mortality, and outcomes of critically ill patients with AKI requiring dialysis (AKI-RRT) and with COVID-19 in the megalopolis of São Paulo, Brazil. METHODS: This multicenter, retrospective, observational study was conducted in the intensive care units of 13 public and private hospitals in the metropolitan region of the municipality of São Paulo. Patients hospitalized in an intensive care unit, aged ≥ 18 years, and treated with RRT due to COVID-19-associated AKI were included. RESULTS: The study group consisted of 375 patients (age 64.1 years, 68.8% male). Most (62.1%) had two or more comorbidities: 68.8%, arterial hypertension; 45.3%, diabetes; 36.3%, anemia; 30.9%, obesity; 18.7%, chronic kidney disease; 15.7%, coronary artery disease; 10.4%, heart failure; and 8.5%, chronic obstructive pulmonary disease. Death occurred in 72.5% of the study population (272 patients). Among the 103 survivors, 22.3% (23 patients) were discharged on RRT. In a multiple regression analysis, the independent factors associated with death were the number of organ dysfunctions at admission and RRT efficiency. CONCLUSION: AKI-RRT associated with COVID-19 occurred in patients with an elevated burden of comorbidities and was associated with high mortality (72.5%). The number of organ dysfunctions during hospitalization and RRT efficiency were independent factors associated with mortality. A meaningful portion of survivors was discharged while dependent on RRT (22.3%).

Toxic effect of metal cation binary mixtures to the seaweed Gracilaria domingensis (Gracilariales, Rhodophyta).

The macroalga Gracilaria domingensis is an important resource for the food, pharmaceutical, cosmetic, and biotechnology industries. G. domingensis is at a part of the food web foundation, providing nutrients and microelements to upper levels. As seaweed storage metals in the vacuoles, they are considered the main vectors to magnify these toxic elements. This work describes the evaluation of the toxicity of binary mixtures of available metal cations based on the growth rates of G. domingensis over a 48-h exposure. The interactive effects of each binary mixture were determined using a toxic unit (TU) concept that was the sum of the relative contribution of each toxicant and calculated using the ratio between the toxicant concentration and its endpoint. Mixtures of Cd(II)/Cu(II) and Zn(II)/Ca(II) demonstrated to be additive; Cu(II)/Zn(II), Cu(II)/Mg(II), Cu(II)/Ca(II), Zn(II)/Mg(II), and Ca(II)/Mg(II) mixtures were synergistic, and all interactions studied with Cd(II) were antagonistic. Hypotheses that explain the toxicity of binary mixtures at the molecular level are also suggested. These results represent the first effort to characterize the combined effect of available metal cations, based on the TU concept on seaweed in a total controlled medium. The results presented here are invaluable to the understanding of seaweed metal cation toxicity in the marine environment, the mechanism of toxicity action and how the tolerance of the organism.

Prediction of mono-, bi-, and trivalent metal cation relative toxicity to the seaweed Gracilaria domingensis (Gracilariales, Rhodophyta) in synthetic seawater.

The present study reports a 48-h aquatic metal-toxicity assay based on daily growth rates of the red seaweed Gracilaria domingensis (Gracilariales, Rhodophyta) in synthetic seawater. The median inhibitory concentration (IC50) for each metal cation was experimentally determined, and the ratios of free ions (aqueous complex) were calculated by software minimization of the total equilibrium activity (MINTEQA2) to determine the free median inhibitory concentration (IC50F). A model for predicting the toxicity of 14 metal cations was developed using the generic function approximation algorithm (GFA) with log IC50F values as the dependent variables and the following properties as independent variables: ionic radius (r), atomic number (AN), electronegativity (Xm ), covalent index (Xm (2) r), first hydrolysis constant (|log KOH |), softness index (σp ), ion charge (Z), ionization potential (ΔIP), electrochemical potential (ΔEo ), atomic number divided by ionization potential (AN/ΔIP), and the cation polarizing power for Z(2) /r and Z/AR. The 3-term independent variables were predicted as the best-fit model (log IC50F: -23.64 + 5.59 Z/AR + 0.99 |log KOH | + 37.05 σp ; adjusted r(2) : 0.88; predicted r(2) : 0.68; Friedman lack-of-fit score: 1.6). This mathematical expression can be used to predict metal-biomolecule interactions, as well as the toxicity of mono-, bi-, and trivalent metal cations, which have not been experimentally tested in seaweed to date. Quantitative ion-character relationships allowed the authors to infer that the mechanism of toxicity might involve an interaction between metals and functional groups of biological species containing sulfur or oxygen.

Evaluation of metal toxicity by a modified method based on the fungus Gerronema viridilucens bioluminescence in agar medium.

Metal cation toxicity to basidiomycete fungi is poorly understood, despite its well-known importance in terrestrial ecosystems. Moreover, there is no reported methodology for the routine evaluation of metal toxicity to basidiomycetes. In the present study, we describe the development of a procedure to assess the acute toxicity of metal cations (Na(+), K(+), Li(+), Ca(2+),Mg(2+), Co(2+), Zn(2+), Ni(2+), Mn(2+), Cd(2+), and Cu(2+)) to the bioluminescent basidiomycete fungus Gerronema viridilucens. The method is based on the decrease in the intensity of bioluminescence resulting from injuries sustained by the fungus mycelium exposed to either essential or nonessential metal toxicants. The assay described herein enables us to propose a metal toxicity series to Gerronema viridilucens based on data obtained from the bioluminescence intensity (median effective concentration [EC50] values) versus metal concentration: Cd(2+) > Cu(2+) > Mn(2+) approximately Ni(2+) approximately Co(2+) > Zn(2+) > Mg(2+) > Li(+) > K(+) approximately Na(+) > Ca(2+), and to shed some light on the mechanism of toxic action of metal cations to basidiomycete fungi.

Prediction of metal cation toxicity to the bioluminescent fungus Gerronema viridilucens.

A correlation between the physicochemical properties of mono- [Li(I), K(I), Na(I)] and divalent [Cd(II), Cu(II), Mn(II), Ni(II), Co(II), Zn(II), Mg(II), Ca(II)] metal cations and their toxicity (evaluated by the free ion median effective concentration, EC50(F)) to the naturally bioluminescent fungus Gerronema viridilucens has been studied using the quantitative ion character-activity relationship (QICAR) approach. Among the 11 ionic parameters used in the current study, a univariate model based on the covalent index (X(2) (m)r) proved to be the most adequate for prediction of fungal metal toxicity evaluated by the logarithm of free ion median effective concentration (log EC50(F)): log EC50(F) = 4.243 (± 0.243) -1.268 (± 0.125)· X(2) (m)r (adj-R(2) = 0.9113, Alkaike information criterion [AIC] = -60.42). Additional two- and three-variable models were also tested and proved less suitable to fit the experimental data. These results indicate that covalent bonding is a good indicator of metal inherent toxicity to bioluminescent fungi. Furthermore, the toxicity of additional metal ions [Ag(I), Cs(I), Sr(II), Ba(II), Fe(II), Hg(II), and Pb(II)] to G. viridilucens was predicted, and Pb was found to be the most toxic metal to this bioluminescent fungus (EC50(F)): Pb(II) > Ag(I) > Hg(I) > Cd(II) > Cu(II) > Co(II) ≈ Ni(II) > Mn(II) > Fe(II) ≈ Zn(II) > Mg(II) ≈ Ba(II) ≈ Cs(I) > Li(I) > K(I) ≈ Na(I) ≈ Sr(II)> Ca(II).

Marcadores de prognóstico no abscesso hepático piogênico / Pyogenic liver abscess: analysis of prognostic factors

Objetivo:Analisar os marcadores de prognóstico no abscesso hepático piogênico. Casuística e método: Foram estudados retrospectivamente 26 pacientes admitidos na Unidade de Emergência Armando Lages-Maceió e no Hospital Universitário Prof. Alberto Antunes, da Universidade Federal de Alagoas, com diagnóstico de abscesso hepático piogênico confirmado à laparotomia exploradora, período 1993-99. Foram estudadas as seguintes variáveis: idade, sexo, icterícia, número de abscessos, localização, choque, rotura, diâmetro, hematócrito e número de leucócitos. A análise estatística foi feita pelos testes de Fisher e Mann-Whitney, sendo considerados significantes respectivamente os valores de p<0,01 e p<0,05. Métodos: Dezenove pacientes eram do sexo masculino e sete do feminino. A idade média foi de 31 anos e variou de três a 92 anos. Resultados: as manifestações clínicas principais foram dor abdominal e febre. O abscesso com lesão única no lobo direito foi a apresentação mais frequente. A drenagem cirúrgica com antimicrobianos foi a terapêutica predominante e a mortalidade global doi de 26,9por cento. Os marcadores idade, sexo, número de abscessos, localização, hematócrito e o número de leucócitos não foram significantes, icterícia, rotura, choque séptico e o diâmetro do abscesso foram os marcadores de prognóstico significantes para mortalidade. Conclusão: Os marcadores de prognóstico para evolução desfavorável foram: presença de icterícia, choque séptico, rotura e o diâmetro do abscesso

Abscesso hepático piogênico associado à esquistossomose mansônica / Liver piogenic abscess associated to schistosomiasis

The authors report a case of the 15 year old young man, from endemic zone of schistosomiasis and with a chronic schistosomiasis, was admitted complaining of continuous pain in the right upper quadrant, spreaded to epigastrium and right lower quadrant which, began 10 days before. It was associated to fever, anorexia, hepatomegaly, esplenomegaly and signs of peritoneal irritation without clinical improvement. At laparotomy multiple liver microabscesses were found. Excluded the classic etiology, a liver biopsy was done and showed Schistossoma mansoni eggs, surrounded by the same inflamatory cells of microabscesses. This suggested that they have been the predisposing cause for the formation of liver abscesses, as shown in the literature. Schistosomiasis can be complicated with pylephlebitis, immunodepression and granulomatous reaction, central lobular necrosis and a raise in the infection risk. The described data suggest the schistosomiasis as the etiology of hepatic microabscesses, mainly in endemic zones