Acute Kidney Injury ; etiology ; Adult ; Burns, Chemical ; complications ; surgery ; Chromates ; toxicity ; Humans ; Male ; Young Adult

OBJECTIVETo investigate the effect of bone mesenchymal stem cell (BMSC) transplantation on repair of glomerular podocytes and on the Nephrin expression in rats with puromycin aminonucleoside (PAN) -induced nephrosis.

METHODSForty-five Sprague-Dawley rats were randomly divided into three groups (n=15 each): a nephrosis model group that received a single intraperitoneal injection of PAN (0.15 mg/g); a BMSC transplantation group that received a single intraperitoneal injection of PAN (0.15 mg/g) followed by BMSC transfusion; a control group that received a single intraperitoneal injection of normal saline. Ten days after injection, the rats were sacrificed. The 24 hrs urinary protein content and serum albumin and cholesterol levels were measured 24 hrs before sacrifice. Changes of glomerular podocytes were observed under an electron microscope. Brdu labeled positive cells in kidneys were measured by immunohistochemical technology. RT-PCR and Western blot were used to assess the expression of mRNA and protein of Nephrin.

RESULTSIn the nephrosis model group, urinary protein and blood cholesterol contents increased, plasma albumin content decreased compared with those in the control group. Extensive fusion of podocyte foot processes was observed in the nephrosis model group. The BMSC transplantation group had decreased urinary protein and blood cholesterol contents and increased plasma albumin content compared with the nephrosis model group. Fusion of podocyte foot processes was also improved. Brdu labeled positive cells were seen in kidneys in the BMSC transplantation group, but not in the nephrosis model and the control groups. Nephrin mRNA and protein expression decreased significantly in the nephrosis model group compared with that in the control group. The BMSC transplantation group had increased Nephrin mRNA and protein expression compared with the nephrosis model group.

CONCLUSIONSBMSCs can repair glomerular podocytes in PAN-induced nephrosis rats, and the changes of Nephrin expression may be involved in the process.

Animals ; Bromodeoxyuridine ; metabolism ; Kidney ; pathology ; Male ; Membrane Proteins ; genetics ; Mesenchymal Stem Cell Transplantation ; Nephrosis, Lipoid ; chemically induced ; pathology ; therapy ; Podocytes ; pathology ; Puromycin Aminonucleoside ; toxicity ; Rats ; Rats, Sprague-Dawley ; Reverse Transcriptase Polymerase Chain Reaction

BACKGROUNDThe recurrence of pterygium after surgery is high. A variety of adjunctive treatment approaches have been developed to improve the clinical efficacy and many related articles have been published. This study aimed to determine the risk for postoperative pterygium recurrence comparing autologous conjunctival transplantation (ACT) versus mitomycin C (MMC).

METHODSRelevant literature published until December 2010 in Medline, Embase, Cochrane, Cochrane library, Science Citation Index, and Google Scholar were searched. Qualified random clinical trial (RCT) studies on the comparison of recurrence rate of pterygium after ACT and MMC treatment were included in this study.

RESULTSEight RCTs with 663 eyes entered the final analysis. The recurrent rate of pterygium was 8.7% (30/343) for ACT and 18.75% (60/320) for MMC. Using fixed-effect meta analysis, we found that the recurrence was significantly lower after ACT than MMC treatment (odds ratio (OR) = 0.40, 95% confidence index (CI), 0.25 - 0.63, P < 0.0001). In sensitivity analyses, we employed random-effects model and excluded studies of low quality or studies in which MMC was administrated after the operation. All the sensitivity analyses confirmed that ACT led to lower recurrence rates than MMC. Sub-group analysis revealed that the recurrence rate was 20.2% (20/99) and 27.65% (26/94) for conjunctival autograft (CA) and MMC respectively, and no significant difference in the recurrence rate was detected (OR = 0.65, 95%CI 0.33 - 1.28, P = 0.22). However, we found that conjunctival limbal autograft (CLA) had lower recurrence rate than MMC (OR = 0.26, 95%CI 0.14 - 0.48, P = 0.0001).

CONCLUSIONCLA has better therapy efficacy against the recurrence of pterygium than MMC.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Conjunctiva ; transplantation ; Humans ; Middle Aged ; Mitomycin ; therapeutic use ; Pterygium ; therapy ; Randomized Controlled Trials as Topic ; Transplantation, Autologous

OBJECTIVETo observe the antimicrobial activity of topical agents commonly used for burns on Acinetobacter baumannii (AB) in both free and biofilm states, and their synergistic effect with ambroxol on AB within biofilm.

METHODSEleven AB strains were isolated from wound excretion, respiratory tract, and blood of patients hospitalized in our hospital from August 2005 to April 2007. (1) The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of mafenide acetate and chlorhexidine acetate to free AB (including drug-resistant, drug-sensitive, and standard strains) were determined by dilution method. (2) AB was cultured with LB or TSB medium for 12, 24, and 48 h to form biofilm, and it was treated with above-mentioned two topical agents in MBC (mafenide group and chlorhexidine group) for 30 min. Biofilm not treated by topical agent was used as control group. The biofilm thickness was determined with confocal laser scanning microscope. The proportion of living bacteria in biofilm was calculated. AB biofilm in each topical agent group was mixed and inoculated into LB culture dish to observe the growth of bacteria. (3) AB was cultured with LB medium for 48 h to form biofilm, which was respectively treated by above-mentioned two topical agents in MBC (mafenide group and chlorhexidine group) and combination of each topical agent with 3.75 mg/mL ambroxol solution (ambroxol + mafenide group and ambroxol + chlorhexidine group) for 30 min. Biofilm not treated by topical agents was used as control group. Growth of bacteria in biofilm was detected with MTT method (denoted as absorbance value). Data were processed with one-way analysis of variance and LSD-t test.

RESULTS(1) MIC of mafenide acetate and chlorhexidine acetate for free AB was respectively 25.00 mg/mL and 0.03 mg/mL. MBC of both agents for free AB was the same as their MIC. (2) Among three groups, the thickness of biofilm of sensitive AB was thicker than that of drug-resistant bacteria at most of the time points. Compared with those in control group, biofilm thickness and proportion of living bacteria in biofilm were slightly decreased in mafenide and chlorhexidine groups. The growth of bacteria was abundant in each group. (3) Absorbance value of drug-resistant bacteria in control, mafenide, and chlorhexidine groups was respectively 0.776 ± 0.071, 0.625 ± 0.063, and 0.420 ± 0.068. Absorbance value of drug-resistant bacteria in ambroxol + mafenide group (0.174 ± 0.089) was significantly lower than that of control group (t = 11.823, P = 0.000) and mafenide group (t = 9.248, P < 0.01). Absorbance value of ambroxol + chlorhexidine group (0.178 ± 0.044) was significantly lower than that of control group (t = 16.009, P = 0.000) and chlorhexidine group (t = 6.681, P < 0.01).

CONCLUSIONSDrug-resistant AB forms biofilm readily, which prevents topical agents from killing the bacteria inside. Combined use of ambroxol with topical agents gives synergistic effect on killing AB in biofilm in the wound.

Acinetobacter baumannii ; drug effects ; isolation & purification ; Anti-Bacterial Agents ; pharmacology ; Biofilms ; drug effects ; Burns ; microbiology ; Chlorhexidine ; pharmacology ; Drug Resistance, Bacterial ; Humans ; Mafenide ; pharmacology ; Microbial Sensitivity Tests

OBJECTIVETo study the changes in expression of quorum sensing gene aba I in Acinetobacter baumannii (AB) strains isolated from burn patients during biofilm formation process, and its influences on the extracellular matrix of biofilm and drug resistance of AB.

METHODSSix drug-resistant and five drug-sensitive AB strains isolated from wound excretion, blood and venous catheter were collected from burn patients hospitalized in Ruijin hospital of Shanghai Jiao Tong University School of Medicine from January to October 2011. The AB standard strain ATCC 19606 was used as control. (1) Clinical strains and standard strain were normally cultured 10, 24, and 48 h respectively in vitro. The bacteria samples were stained with propidium iodide to measure biofilm thickness with confocal laser scanning microscope. (2) Clinical strains and standard strain were cultured in tubes 10, 24, and 48 h respectively in vitro under shaking condition. The bacteria floating in the medium were regarded as free bacteria, while those adhered to the tube wall as the bacteria within biofilm (biofilm bacteria). Relative expression value of genes aba I and pgaB was detected by real-time fluorescent quantitative PCR with the expression value of the standard strain set at 1. Data were processed with analysis of variance.

RESULTS(1) At post culture hour (PCH) 10, 24, 48, biofilm thickness of clinical strains was thicker than that of standard strain; biofilm thickness of drug-resistant strains [(28.8 ± 0.6), (31.7 ± 1.1), and (38.1 ± 3.1) µm] was respectively thicker than that of drug-sensitive strains [(17.1 ± 0.4), (20.1 ± 1.6), and (25.8 ± 1.7) µm, with F value respectively 1274.38, 206.60, and 61.73, P values all below 0.05]. (2) Biofilm bacteria: at PCH 10, 24, 48, expression values of aba I in drug-resistant strains (6.6 ± 1.7, 25.7 ± 3.5, 9.8 ± 3.6) were much higher than those of drug-sensitive strains (2.7 ± 1.0, 15.0 ± 3.5, 4.7 ± 3.2, with F value respectively 21.82, 25.24, and 6.22, P values all below 0.05); expression values of pgaB in drug-resistant strains (37.4 ± 1.1, 44.5 ± 3.6, 33.1 ± 11.5) were obviously higher than those of drug-sensitive strains (14.6 ± 0.8, 20.0 ± 6.9, 18.7 ± 6.8, with F value respectively 1488.44, 57.26, and 6.01, P values all below 0.05). (3) Free bacteria: at PCH 10, 24, 48, there was no significant statistical difference between drug-resistant strains and drug-sensitive strains in expression value of aba I (with F value respectively 0.24, 2.33, and 0.11, P values all above 0.05); expression values of pgaB in drug-resistant strains (13.8 ± 3.8, 12.5 ± 2.9, 23.7 ± 2.1) were obviously higher than those of drug-sensitive strains (7.0 ± 5.9, 5.0 ± 1.3, 15.6 ± 6.7, with F value respectively 5.44, 28.42, and 7.76, P values all below 0.05). (4) Comparison between biofilm bacteria and free bacteria in resistant strains: expression value of aba I in biofilm bacteria at each time point was respectively higher than that of free bacteria (with F value respectively 43.69, 286.61, and 9.98, P values all below 0.05); expression values of pgaB in biofilm bacteria at PCH 10, 24 were higher than those in free bacteria (with F value respectively 214.26 and 283.20, P values below 0.05). (5) Comparison between biofilm bacteria and free bacteria in sensitive strains: expression value of aba I in BF bacteria at PCH 24 was higher than that of free bacteria (F = 70.28, P < 0.05); expression values of pgaB in biofilm bacteria at PCH 10, 24 were higher than those of free bacteria (with F value respectively 8.03 and 22.62, P values below 0.05).

CONCLUSIONSDuring biofilm formation process, the increasing expression of quorum sensing gene aba I in drug-resistant AB strains isolated from burn patients may up-regulate the expression of gene pgaB, which leads to high production of extracellular matrix and biofilm formation, and enhances drug resistance of AB.

Acinetobacter Infections ; Acinetobacter baumannii ; genetics ; isolation & purification ; Biofilms ; Burns ; microbiology ; Drug Resistance, Bacterial ; Genes, Bacterial ; Humans

OBJECTIVETo observe expressions of pgaABC gene clusters and changes in biofilm (BF) phenotype in Acinetobacter baumannii (AB) isolated from burn patients.

METHODSFrom January 2009 to October 2010, 24 strains of AB isolated from burn patients hospitalized in our burn wards were collected for the study, while the standard strain ATCC 19606 was used as control. Expressions of pgaABC gene clusters were detected by real time fluorescence quantitative RT-PCR. All strains were cultured for 16 hours in vitro, BF with semi-quantitative detection was respectively evaluated by modified microtiter-plate test under stable condition and tube test under shaking condition for expression of absorbance value. All strains were cultured for 48 hours in vitro, then stained with fluorescent agent and collected for measurement of BF thickness with confocal laser scanning microscopy (CLSM). Data were processed with t test.

RESULTS(1) The expression of pgaB gene (27.91 ± 7.93) in clinical AB strains was much higher than that of standard strain ATCC 19606 (1.00, t = 5.77, P < 0.05). There was no statistical difference in expression of pgaA and pagC genes between standard strain ATCC 19606 (1.00) and clinical AB strains (1.01 ± 0.28, 1.15 ± 0.38, with t value respectively 0.04, 0.64, P values all above 0.05). (2) After being cultured for 16 hours, BF of clinical AB strains cultured under shaking condition formed distinct "purple circle", and its absorbance value (1.25 ± 0.31) was higher than that in standard strain ATCC 19606 (0.76 ± 0.03, t = 2.67, P < 0.05). There was no obvious difference in absorbance value between clinical AB strains and standard strain ATCC19606 cultured under stable condition. (3) After being culture for 48 hours, green fluorescence intensity and distribution in extracellular matrix of clinical AB strains were stronger as compared with those of standard strain ATCC 19606, and BF thickness in clinical AB strains [(27.3 ± 9.4)µm] was thicker than that in standard strain ATCC 19606 [(15.6 ± 1.7) µm, t = 2.09, P < 0.05].

CONCLUSIONSThe high expression of pgaB gene in AB strains isolated from burn patients can induce production of extracellular matrix, which may be related to increase in the ability and thickness of BF formation.

Acinetobacter Infections ; microbiology ; Acinetobacter baumannii ; genetics ; isolation & purification ; Biofilms ; Burns ; microbiology ; Genes, Bacterial ; Humans ; Multigene Family

OBJECTIVETo monitor genotypes and drug-resistance trend of Acinetobacter baumannii (AB) isolated from burn wards.

METHODSTwenty-six strains of AB isolated from wound secretion, venous catheter, and blood were collected from burn patients hospitalized in our burn wards from November 2008 to February 2009, and June to September 2010. Homogeneous genotype analysis was performed with repetitive extragenic palindromic PCR, and drug-resistance rate to 13 antibiotics including amikacin, gentamicin, etc., which were commonly used in clinic, was tested by K-B paper disk diffusion. The data of drug-resistance rate were processed with chi-square test.

RESULTS(1) Sixteen AB strains were multi-drug resistant (MDR), 9 AB strains were pan-drug resistant (PDR). Among all strains, the resistance rate to gentamicin, piperacillin, piperacillin/tazobactam, cefuroxime, cefotaxime, ceftazidime, cefepime, ciprofloxacin, imipenem, and meropenem was respectively higher than 90.00%; the resistance rate against cefoperazone/sulbactam was the lowest (11/26, 42.31%). There were obvious difference among the drug-resistance rates of AB strains to 13 antibiotics (with rates from 42.31% to 100.00%, χ(2) = 97.371, P < 0.05). (2) There were 7 genotypes among 26 AB strains, respectively type A (17), type B (3), type C (2), type D (1), type E (1), type F (1), and type G (1). Out of the 17 AB strains in A genotype, 1 strain was from 2008, 1 strain was from 2009, 15 strains were from 2010, and among them 11 strains were collected from wound secretion and 6 strains were obtained from blood and venous catheter.

CONCLUSIONSAB strains in A genotype are dominant in our burn wards in recent years, which are MDR or PDR to commonly used antibiotics. Cefoperazone/sulbactam is the drug of choice for burn patients with AB infection.

Acinetobacter Infections ; epidemiology ; microbiology ; Acinetobacter baumannii ; drug effects ; genetics ; Burns ; microbiology ; Cross Infection ; epidemiology ; microbiology ; Drug Resistance, Multiple, Bacterial ; Genes, Bacterial ; Humans

Infections caused by Acinetobacter baumannii (AB) have emerged as a knotty clinical problem in the burn wards due to its omni-resistance to antibiotics and high prevalence. Although our knowledge in regard to the pathogenesis and the resistance mechanisms of AB is increasing, the available treatment remains much limited. Measures to effectively control nosocomial infection are warranted. Meanwhile, development of novel therapeutic agents or combination of antibiotics should be considered.
Acinetobacter Infections ; epidemiology ; Acinetobacter baumannii ; drug effects ; Anti-Infective Agents ; pharmacology ; Burns ; microbiology ; Drug Resistance, Multiple, Bacterial ; Humans

OBJECTIVETo observe the biofilm (BF) formation of Staphylococcus aureus (SA), Acinetobacter baumannii (AB) and Pseudomonas aeruginosa (PA) on the surface of deep vein catheters in burn patients after infection.

METHODSThe bacteria from deep vein catheters in 20 patients hospitalized from November 2008 to August 2009 were isolated, and were compared with their respective standard stains. Catheters tips were examined with scanning electron microscope (SEM). The semi-quantitative adhesion assay of bacterial BF was performed with modified microtiter-plate test, and the thickness of BF was scanned and measured by confocal laser scanning microscopy (CLSM) after double fluorescence staining, after being cultured in vitro for 12, 24, 48, 72 hours and 5 days, respectively. Data were processed with grouped t test.

RESULTSSix strains of SA, 8 strains of AB, and 6 strains of PA, all drug resistant, were isolated from the deep vein catheters. SEM showed that the BF structures on the inner surfaces of catheters were in diverse in their shape and degree, characterized by adherence and flake formation, and embedded in polysaccharide matrix. BF gathered in clusters, forming three-dimensional structure, in which small amount of red blood cells were found. A small number of bacteria were incompletely embedded, with some bacteria adhered to them. The absorbance values for SA after 24, 48 and 72 hours of culture (PCH) were above the cut-off value, the same for AB at PCH 12, 24, 48 and 72, and PA after PCH 48. Except for PA standard strain, CLSM showed scattered green fluorescence, mainly close to the bottom of plate, while the red fluorescence was observed in full scope at PCH 24 for each strain. At PCH 48 green fluorescence increased obviously and extended upward from the bottom, overlapping partly with red fluorescence, forming yellow fluorescence, and among the bacteria it was most obvious in AB culture, with SA the next. Compared with those of the standard stains, the intensity and quantity of fluorescence from the clinical strains were stronger; at PCH 72 the green fluorescence increased obviously especially for PA and its standard strain, while the yellow fluorescence was full of the scope for other strains. On in vitro culture day 5, the green fluorescence was dispersed and was obvious on the bottom of the plate. BF mature time for AB and SA was PCH 48, and for PA was PCH 72. The BF thickness of AB was (18.2 +/- 3.6) microm at PCH 72, which was thicker than that [(9.4 +/- 2.6) microm] of its standard strain (t = 5.42, P < 0.05), and was also the thickest among the three clinically found strains.

CONCLUSIONSSA, AB and PA, which are commonly found bacteria in burn patients, can form BF in deep vein catheters. Their ability to form BF seems to be stronger than other usually pathogenic strains, especially AB, which is the important pathogen leading to catheter related infection.

Acinetobacter Infections ; microbiology ; Acinetobacter baumannii ; growth & development ; Bacterial Adhesion ; Biofilms ; Burns ; microbiology ; Catheters ; microbiology ; Humans ; Pseudomonas Infections ; microbiology ; Pseudomonas aeruginosa ; growth & development ; Staphylococcal Infections ; microbiology ; Veins ; microbiology

OBJECTIVE: To investigate the changes of iron content in serum and liver, ferritin content in serum, percentage of myeloperoxidase (MPO) positive granulocyte in rabbits after different serious trauma and to explore the relationship between these changes and multiple organ failure (MOF). METHODS: Rabbit trauma models were established. Iron content in serum and liver, ferritin content in serum and the percentage of MPO positive granulocyte were measured at different time after trauma. RESULTS: After trauma, iron content in serum decreased sharply in early period (12-36h) and increased gradually to normal level in mild traumatic group after 60 h. Iron content in serum remained lower level in severe traumatic and death group 60 h after trauma. Iron content in liver obviously increased in death group. The changes of ferritin content in serum in mild traumatic were not obvious. Ferritin contents in serum in severe injury group and death group were slightly higher in early period and decreased in later period. The percentage of MPO positive granulocyte increased in early period after trauma. The percentage began to decrease 6 d after trauma and returned to normal level in mild traumatic group. The percentage obviously was significantly lower than normal levels in severe traumatic group and death group 6 d after trauma. Some rabbits died 60 h-6 d after severe trauma, and the pathological changes in the other organs were consistent with MOF. CONCLUSION Trauma can cause the serum iron, ferritin levels and percentage of MPO positive granulocyte changes. Severe trauma can cause uncompensated changes of these indicators, which could be the main mechanisms of MOF and death.
Animals ; Disease Models, Animal ; Ferritins/metabolism* ; Injury Severity Score ; Iron/metabolism* ; Leukocyte Count ; Liver/metabolism* ; Male ; Multiple Organ Failure/pathology* ; Multiple Trauma/pathology* ; Peroxidase/metabolism* ; Rabbits ; Time Factors ; Wounds and Injuries/pathology*