RESUMO
INTRODUCTION: Proteinuria in burn patients is common, and may be associated with acute kidney injury (AKI) and adverse outcomes. We evaluated the incidences, outcomes, characteristics and determinants of proteinuria and its influence on AKI and outcomes in burn patients. METHODS: This retrospective study was carried out in a hospital's burn department. The study population consisted of patients with burn injuries admitted during a five-year period. Positive urine dipstick readings were defined as mild (± or 1+) or heavy (≥ 2+) proteinuria, and AKI was diagnosed and staged according to the Risk, Injury, Failure, Loss, End Stage (RIFLE) classification system. Patient characteristics, management and outcomes were evaluated for associations with proteinuria using nonparametric tests, chi-square (χ(2)) tests and binary logistic regression. RESULTS: Of the patients admitted to the burn unit during the study period (n = 2,497), 865 (34.64%) were classified as having proteinuria. In the patients whose total burn surface areas (TBSA) were > 30% (n = 396), 271 patients (68.43%) had proteinuria and 152 of these patients (56.09%) met AKI criteria. No patients without proteinuria developed AKI. Intensive care unit (ICU) mortality rates were 0.8%, 16.67% and 30.77% (P < 0.001) in the groups with no, mild and heavy proteinuria, respectively. Logistic regression analysis identified proteinuria (OR 4.48; 95% CI, 2.824 to 7.108; P < 0.001) and sequential organ failure assessment (OR 1.383; 95% CI, 1.267 to 1.509; P < 0.001) as risk factors for AKI. CONCLUSIONS: We observed a high prevalence of proteinuria in patients with severe burns (> 30% TBSA). Severely burned patients with proteinuria had a high risk of developing AKI and a poor prognosis for survival. This suggests that proteinuria should be used for identifying burn patients at risk of developing AKI.
Assuntos
Injúria Renal Aguda/epidemiologia , Queimaduras/epidemiologia , Proteinúria/epidemiologia , Índice de Gravidade de Doença , Injúria Renal Aguda/diagnóstico , Adulto , Queimaduras/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteinúria/diagnóstico , Estudos Retrospectivos , Adulto JovemRESUMO
Hypoxia-inducible factor (HIF)-1alpha is a key regulator of anaerobic energy metabolism. We asked the following question: Does the breakdown of microtubular structures influence glycolysis in hypoxic cardiomyocytes by regulating HIF-1alpha? Neonatal rat cardiomyocytes were cultured under hypoxic conditions, while microtubule-stabilizing (paclitaxel) and -depolymerizing (colchicine) agents were used to change microtubular structure. Models of high microtubule-associated protein 4 (MAP4) expression and RNA interference of microtubulin expression were established. Microtubular structural changes and intracellular HIF-1alpha protein distribution were observed with laser confocal scanning microscopy. Content of key glycolytic enzymes, viability, and energy content of cardiomyocytes were determined by colorimetry and high-performance liquid chromatography. HIF-1alpha protein content and mRNA expression were determined by Western blotting and real-time PCR, respectively. Low doses of microtubule-stabilizing agent (10 mumol/l paclitaxel) and enhanced expression of MAP4 stabilized the reticular microtubular structures in hypoxic cardiomyocytes, increased the content of key glycolytic enzymes, ameliorated energy supply and enhanced cell viability, and upregulated HIF-1alpha protein expression and endonuclear aggregation. In contrast, the microtubule-depolymerizing agent (10 mumol/l colchicine) or reduced microtubulin expression had adverse affects on the same parameters, in particular, HIF-1alpha protein content and endonuclear aggregation. We conclude that microtubular structural changes influence glycolysis in the early stages of hypoxia in cardiomyocytes by regulating HIF-1alpha content. Stabilizing microtubular structures increases endonuclear and total HIF-1alpha expression, content of key glycolytic enzymes, and energy supply. These findings provide potential therapeutic targets for ameliorating cell energy metabolism during early myocardial hypoxia.
Assuntos
Núcleo Celular/metabolismo , Glicólise/fisiologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Hipóxia/metabolismo , Microtúbulos/fisiologia , Miócitos Cardíacos/fisiologia , Trifosfato de Adenosina/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Colchicina/farmacologia , Relação Dose-Resposta a Droga , Metabolismo Energético/efeitos dos fármacos , Glicólise/efeitos dos fármacos , Hipóxia/fisiopatologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Microtúbulos/efeitos dos fármacos , Modelos Animais , Miócitos Cardíacos/citologia , Paclitaxel/farmacologia , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Moduladores de Tubulina/farmacologiaRESUMO
Emulsified isoflurane (EIso) preconditioning can induce cardioprotection. We investigated whether EIso application after ischemia protects hearts against reperfusion injury and whether it is mediated by the inhibition of apoptosis. Rats were subjected to 30-min coronary occlusion followed by 180-min reperfusion. At the onset of reperfusion, rats were intravenously administered saline (sham, control group), 30 % intralipid (IL group) or 2 ml kg(-1) EIso (EIso group) for 30 min. After reperfusion, infarct sizes, myocardial apoptosis and expression of Bcl-2, Bax and caspase-3 proteins were determined. Hemodynamic parameters were not different among groups. Compared with control and intralipid group, EIso limited infarct size, inhibited apoptosis, increased the expression of Bcl-2, decreased the expression of Bax, cleaved caspase-3, and enhanced Bcl-2/Bax ratio. EIso protects hearts against reperfusion injury when administered at the onset of reperfusion, which may be mediated by the inhibition of apoptosis via modulation of the expression of pro- and anti-apoptotic proteins.
Assuntos
Pós-Condicionamento Isquêmico/métodos , Isoflurano/administração & dosagem , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Animais , Apoptose/efeitos dos fármacos , Emulsões/administração & dosagem , Masculino , Fosfolipídeos/administração & dosagem , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Ratos , Ratos Sprague-Dawley , Óleo de Soja/administração & dosagem , Proteína X Associada a bcl-2/biossínteseRESUMO
The carbapenemases have recently emerged as molecules implicated in one of the most feared bacterial resistance mechanisms because of their ability to hydrolyze virtually all lactamase agents and their highly mobile genes. This study aimed to investigate the prevalence of carbapenemase and antimicrobial susceptibilities of Pseudomonas aeruginosa isolated from burn patients in Chongqing, China. Antimicrobial susceptibility of 111 isolates was determined by the disc agar diffusion test and the agar dilution method. Random Amplification of Polymorphic DNA polymerase chain reaction analysis revealed 111 P. aeruginosa 42 genotypes. Carbapenemase genes were amplified by polymerase chain reaction and the sequence verified by blast. Ninety-three of 111 (83.8%) isolates were resistant to imipenem; all of them had developed multidrug resistance and exhibited higher resistant rates compared with the imipenem-susceptible Pseudomonas. Ciprofloxacin was the most effective antipseudomonal agent. Thirty-three of the isolates were identified to contain the metallo-ß-lactamase blaIMP-4 gene and belong to different Random Amplification of Polymorphic DNA polymerase chain reactiongenotypes. In conclusion, the high prevalence of multidrug resistance (94.6%) and the production of blaIMP-4 genes in P. aeruginosa isolates in burn patients highlight the necessity of considering these issues in burn hospitals.
Assuntos
Proteínas de Bactérias/genética , Queimaduras/microbiologia , Pseudomonas aeruginosa/genética , beta-Lactamases/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Unidades de Queimados , Criança , Pré-Escolar , China , DNA Bacteriano/genética , Farmacorresistência Bacteriana Múltipla/genética , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Pseudomonas aeruginosa/isolamento & purificação , Adulto JovemRESUMO
Mitochondrial damage plays an important role in mediating postburn cardiac injury. To elucidate the pivotal mitochondrial proteins and pathways underlying postburn cardiac injury, mitochondria were purified from control and postburn rat hearts. 2-dimensional gel electrophoresis (2-DE) and HPLC-chip-MS/MS analyses revealed 9 differentially expressed proteins, 3 of which were further validated by Western blotting. The differential expression of these mitochondrial proteins was accompanied by increased levels of oxidative cardiac damage and decreased levels of cardiac output. One of the differentially expressed proteins, mitochondria translation elongation factor Tu (EF-Tumt), was hypothesized to contribute crucially to postburn oxidative cardiac damage. The small interfering RNA (siRNA)-mediated downregulation of EF-Tumt in cultured rat cardiomyocytes increased reactive oxygen species (ROS) generation and protein carbonyl levels, and led to cell damage. The potential pathway of this process was associated with respiratory chain complex I deficiency. Together, these results demonstrate the mitochondrial responses to severe burn, and indicate a pathway by which decreased EF-Tumt expression mediates oxidative damage in postburn myocardium.
Assuntos
Queimaduras/metabolismo , Mitocôndrias Cardíacas/metabolismo , Proteínas Mitocondriais/metabolismo , Proteínas Musculares/metabolismo , Miocárdio/metabolismo , Fator Tu de Elongação de Peptídeos/metabolismo , Animais , Queimaduras/patologia , Complexo I de Transporte de Elétrons/metabolismo , Regulação da Expressão Gênica , Masculino , Mitocôndrias Cardíacas/patologia , Miocárdio/patologia , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismoRESUMO
BACKGROUND: Recent studies in animal models suggest that serum amyloid P (SAP) can affect burn wound healing. However, the role of SAP in a clinical setting remains unknown. METHODS: We enrolled 88 patients with third degree burn wounds. All the patients were candidates for auto-skin graft procedure using stamp skin graft. The complete graft healing time and the number of survived grafts were recorded. Serum SAP levels were assessed 1 day before operation. RESULTS: There was no significant difference in SAP level between controls and patients. There were no significant differences noted among the patients with different burn surface area. However, when the patients in each group were stratified by SAP levels, the mean complete healing time of grafted wound and the mean numbers of survived skin grafts were significantly different. Spearman's analyses showed that the serum SAP levels negatively correlated with the complete wound healing time and mean numbers of survived skin grafts. Logistic regression analysis showed that the serum SAP levels and mean numbers of survived skin grafts were potent independent factors contributing to wound healing. CONCLUSIONS: The results of this study suggest that the serum SAP levels may be an easy detected predictor for the healing of burn wounds.
Assuntos
Queimaduras/metabolismo , Queimaduras/cirurgia , Sobrevivência de Enxerto , Componente Amiloide P Sérico/metabolismo , Transplante de Pele , Cicatrização , Adulto , Queimaduras/imunologia , Queimaduras/fisiopatologia , Estudos de Casos e Controles , Feminino , Humanos , MasculinoRESUMO
Mitochondrial membrane permeability has received considerable attention recently because of its key role in apoptosis and necrosis induced by physiological events such as hypoxia. The manner in which mitochondria interact with other molecules to regulate mitochondrial permeability and cell destiny remains elusive. Previously we verified that hypoxia-induced phosphorylation of microtubule-associated protein 4 (MAP4) could lead to microtubules (MTs) disruption. In this study, we established the hypoxic (1% O(2)) cell models of rat cardiomyocytes, H9c2 and HeLa cells to further test MAP4 function. We demonstrated that increase in the pool of MAP4 could promote the stabilization of MT networks by increasing the synthesis and polymerization of tubulin in hypoxia. Results showed MAP4 overexpression could enhance cell viability and ATP content under hypoxic conditions. Subsequently we employed a yeast two-hybrid system to tag a protein interacting with mitochondria, dynein light chain Tctex-type 1 (DYNLT1), by hVDAC1 bait. We confirmed that DYNLT1 had protein-protein interactions with voltage-dependent anion channel 1 (VDAC1) using co-immunoprecipitation; and immunofluorescence technique showed that DYNLT1 was closely associated with MTs and VDAC1. Furthermore, DYNLT1 interactions with MAP4 were explored using a knockdown technique. We thus propose two possible mechanisms triggered by MAP4: (1) stabilization of MT networks, (2) DYNLT1 modulation, which is connected with VDAC1, and inhibition of hypoxia-induced mitochondrial permeabilization.
Assuntos
Dineínas/metabolismo , Regulação da Expressão Gênica , Hipóxia/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/metabolismo , Mitocôndrias/metabolismo , Canal de Ânion 1 Dependente de Voltagem/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Sobrevivência Celular , Proteínas de Fluorescência Verde/metabolismo , Células HeLa , Humanos , Microscopia Confocal/métodos , Permeabilidade , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/metabolismo , Técnicas do Sistema de Duplo-HíbridoRESUMO
OBJECTIVE: To investigate the influence of microtubule depolymerization of myocardial cells on distribution and activity of mitochondria, and energy metabolism of cells in adult rats. METHODS: Myocardial cells of SD adult rats and SD suckling rats were isolated and cultured. They were divided into adult and suckling rats control groups (AC and SC, normally cultured without any stimulating factor), adult and suckling rats microtubule depolymerization agent groups (AMDA and SMDA, cultured with 8 micromol/L colchicine containing nutrient solution for 30 minutes) according to the random number table. (1) The expression of polymerized beta tubulin in myocardial cells of adult and suckling rats was detected with Western blot. (2) Myocardial cells of rats in AC and AMDA groups were collected. The expression of cytochrome c was detected with Western blot. Distribution of voltage-dependent anion channels (VDAC) and polymerized beta tubulin in myocardial cells were observed with immunofluorescent staining. Mitochondrial inner membrane potential was determined with immunocytochemical method. Activity of myocardial cells was detected with MTT method. Contents of ATP, adenosine diphosphate (ADP), and adenosine monophosphate (AMP) and energy charge of cells were determined with high performance liquid chromatography. RESULTS: (1) The expression of polymerized beta tubulin:in AMDA group it was 0.52 + or - 0.07, which was obviously lower than that (1.25 + or - 0.12) in AC group (F = 31.002, P = 0.000); in SMDA group it was 0.76 + or - 0.12, which was significantly lower than that (1.11 + or - 0.24) in SC group (F = 31.002, P = 0.000), but was obviously higher than that in AMDA group (F = 31.002, P = 0.009). (2) The expression of cytochrome c in AC group was 0.26 + or - 0.03, which was obviously lower than that (1.55 + or - 0.13) in AMDA group (t = -24.056, P = 0.000). (3) Immunofluorescent staining result: in AC group, microtubules of myocardial cells were in linear tubiform, distributed in parallel with myocardial fiber; VDAC staining result showed that mitochondria were in granular form, distributed in the same direction as microtubules. In AMDA group, the normal distribution regularity of microtubules was destroyed, with weakened immune fluorescence intensity, microtubules structure indistinct, continuity lost, rough in appearance, and the distribution of mitochondria became disrupted. (4) Mitochondrial inner membrane potential in AC group fluorescent intensity was 1288 + or - 84, which was obviously higher than that (331 + or - 27) in AMDA group (t = 26.508, P = 0.000). (5) Cellular activity: in AC group absorbance value was 1.75 + or - 0.11, which was obviously lower than that (0.81 + or - 0.07) in AMDA group (t = 17.348, P = 0.000). (6) Energy metabolism: compared with those in AC group, content of ATP decreased, contents of ADP and AMP increased, and ATP/ADP value and energy charge decreased in AMDA group. CONCLUSIONS: Microtubules and mitochondria distribute in the same direction in normal myocardial cells in adult rats. After microtubule depolymerization, mitochondria are arranged in disorder fashion; cytochrome c leaks from mitochondria; mitochondrial membrane potential, energy supply, and cellular activity decrease in the myocardial cells.
Assuntos
Metabolismo Energético , Microtúbulos/metabolismo , Mitocôndrias Cardíacas/metabolismo , Miócitos Cardíacos/metabolismo , Animais , Células Cultivadas , Masculino , Potencial da Membrana Mitocondrial , Ratos , Ratos Sprague-Dawley , Tubulina (Proteína)/metabolismoRESUMO
OBJECTIVE: To investigate the influence of microtubule intervention drugs on glycolytic key enzymes in myocardial cells after hypoxia. METHODS: The primary passage of cultured myocardial cells from neonatal rats were divided into A group (with hypoxia), B group (with hypoxia and administration of l0 micromol/L colchicine), C group (with hypoxia and administration of 5 micromol/L taxol), D group (with hypoxia and administration of 10 micromol/L taxol), E group (with hypoxia and administration of 15 micromol/L taxol). The morphology of microtubule was observed with laser scanning microscope (LSM). The cell vitality was assayed by cell counting kit (CCK). The activities of hexokinase (HK), pyruvate kinase (PK), phosphofructokinase (PFK) and lactate dehydrogenase (LDH) were assayed with colorimetry. RESULTS: In group B and E, the microtubule structure was damaged heavily, and the cell vitality was decreased significantly [The cell vitality was (89.99 +/- 3.47)% in B group and (84.56 +/- 6.61)% in E group, respectively, at 1.0 post hypoxia hour (PHH), and hoth values were obviously lower than that in A group (97.44 +/- 1.76)%, P < 0.01]. The HK, PK and PFK activities decreased obviously. The activities of HK, PK and PFK in group C were similar to those of the A group. Compared with that in other groups, the degree of damage of microtubule structure in D group was milden. The activities of HK, PK and PFK in D group during 0.5 - 6.0 PHH were significantly higher than those in A group. The activity of LDH in each group was increased after hypoxia. CONCLUSION: Proper concentration of microtubule-stabilizing drugs can alleviate the damages to microtubule structure, and enhance the activity of glycolytic key enzymes of myocardial cells at early stage of hypoxia.
Assuntos
Glicólise/efeitos dos fármacos , Microtúbulos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Animais , Hipóxia Celular , Células Cultivadas , Hexoquinase/metabolismo , L-Lactato Desidrogenase/metabolismo , Microtúbulos/metabolismo , Miócitos Cardíacos/enzimologia , Fosfofrutoquinase-1/metabolismo , Piruvato Quinase/metabolismo , Ratos , Ratos Sprague-DawleyRESUMO
OBJECTIVE: To investigate the influence of hypoxia induced microtubule damage on the opening of mitochondrial permeable transition pore (MPTP)of cardiac myocytes and on the decrease of respiratory function in rat. METHODS: Primary cultured myocardial cells from 30 neonatal rats were randomized as normoxic group (A), hypoxia group (B), normoxia with microtubule destabilizing agent group (C, with treatment of 8 micromol/L colchicines for 30 minutes before normoxia), and hypoxia with microtubule stabilizing agent group (D, with treatment of 10 micromol/L taxol for 30 minutes before hypoxia). beta-tubulin immunofluorescence ,the opening of mitochondria permeability transition pore, and the mitochondrial inner membrane potential were detected at 0.5, 1, 3, 6 and 12 post-treatment hours (PTH), and the mitochondrial respiratory function was determined by MTT method. The changes in these indices were also determined in A group at the corresponding time-points. RESULTS: Obvious damage of polymerized microtubule, opening of MPTP, mitochondrial inner membrane potential loss and decrease of myocardial respiratory activity were observed in both group B and C at 0.5 PTH, and they became more and more serious afterwards. However, the changes in the above indices in D group were much better than those in B group (P < 0.05 or 0.01), and no difference was found between D (92.8 +/- 4.0)% and C [(100.0 +/- 0.0) %, P > 0.05] groups. CONCLUSION: Hypoxia played a role in the myocardial microtubule damage as well as in the opening of MPTP. Moreover, hypoxia could also impair the mitochondrial respiratory function. Microtubule destabilizing agent could reproduce well the process of hypoxia induced microtubule damage, while the stabilizing agent exerted protective effect by improving the transition of mitochondrial permeability and the mitochondria respiratory function.