Alteration of gene expression in mice after glaucoma filtration surgery.

To clarify the early alterations of gene expression using a mouse model of glaucoma filtration surgery, we carried out microarray expression analysis. Using BALB/c mice, a filtration surgery model was made by incision of the limbal conjunctiva, followed by the insertion of a 33G needle tip into the anterior chamber, and 11-0 nylon sutures. Subgroups of mice were treated intraoperatively with 0.4 mg/ml mitomycin-C (MMC). At day 3 after surgery the bleb was maintained. The bleb region tissue was sampled 3 days after the filtration surgery, and gene expression analysis was carried out using a mouse Agilent 8 × 60 K array. We found 755 hyperexpressed transcripts in the bleb region compared to control conjunctiva. The hyperexpressed transcripts included epithelial cell metaplasia-related (Il1b, Krt16, Sprr1b), inflammation-related (Ccl2, Il6) and wound healing-related (Lox, Timp1) genes. We also found downregulation of a goblet cell marker gene (Gp2) in the bleb conjunctiva. MMC treatment suppressed elastin (Eln) gene expression and enhanced keratinization-related gene expression (Krt1, Lor) in the bleb region. Our results suggest the importance of epithelial wound healing after filtration surgery, and this filtration surgery model will be a useful tool for further pathophysiological analysis.

Predictors of surgical site skin infection and clinical outcome at caesarean section in the very severely obese: A retrospective cohort study.

INTRODUCTION: The optimal surgical approach for caesarean section is uncertain in women with very severe obesity (body mass index (BMI) >40kg/m2). We aimed to assess maternal and surgical predictors of surgical site skin infection (SSSI) in very severely obese women and to undertake an exploratory evaluation of clinical outcomes in women with a supra-panniculus transverse compared to an infra-panniculus transverse skin incision. MATERIAL AND METHODS: Using a retrospective cohort design, case-records were reviewed of very severely obese women with a singleton pregnancy delivered by caesarean between August 2011 and December 2015 (n = 453) in two maternity hospitals in Scotland. Logistic regression analysis was used to determine predictors for SSSI. Outcomes were compared between women who had a supra-panniculus transverse compared to infra-panniculus transverse skin incision. RESULTS: Lower maternal age was predictive of SSSI, with current smoking status and longer wound open times being marginally significant. Maternal BMI, suture method and material demonstrated univariate associations with SSSI but were not independent predictors. Women with a supra-panniculus transverse skin incision were older (32.9 (4.4), vs. 30.6 (5.7), p = 0.002), had higher BMI (49.2 (7.1), vs. 43.3 (3.3), p<0.001), shorter gestation at delivery (days) (267.7 (14.9), vs. 274.8 (14.5), p<0.001) and higher prevalence of gestational diabetes mellitus (42.6% vs. 21.9%, p = 0.002). SSSI rates did not differ between supra-panniculus transverse (13/47; 27.7%) and infra-panniculus transverse (90/406; 22.2%; p = 0.395) skin incisions. CONCLUSION: SSSI rates are high in very severely obese women following caesarean section, regardless of location of skin incision.

Mycobacterium fortuitum infection of the scalp after a skin graft.

Mycobacterium fortuitum is a non-tuberculous mycobacterium found in the soil and water of most regions of the world, and it can cause disease in immunocompetent and immunocompromised hosts. We present a 52-year-old man who developed a scalp abscess under a free flap for cranium coverage after a motor vehicle accident. Culture of material drained from the abscess grew M. fortuitum.

Metabolism gene signatures and surgical site infections in abdominal surgery.

INTRODUCTION: Surgical site infections (SSI) represent a significant cause of morbidity in abdominal surgery. The objective of this study was to determine the gene expression signature in subcutaneous tissues in relation to SSI. METHODS: To determine differences in gene expression, microarray analysis were performed from bulk tissue mRNA of subcutaneous tissues prospectively collected in 92 patients during open abdominal surgery. 10 patients (11%) developed incisional (superficial and deep) SSI. RESULTS: Preoperative risk factors in patients with SSI were not significantly different from those in patients without wound infections. 1025 genes were differentially expressed between the groups, of which the AZGP1 and ALDH1A3 genes were the highest down- and upregulated ones. Hierarchical clustering demonstrated strong similarity within the respective groups (SSI vs. no-SSI) indicating inter-group distinctness. In a functional classification, genes controlling cell metabolism were mostly down-regulated in subcutaneous tissues of patients that subsequently developed SSI. CONCLUSION: Altered expression of metabolism genes in subcutaneous tissues might constitute a risk factor for postoperative abdominal SSI.

Requirements for Pseudomonas aeruginosa acute burn and chronic surgical wound infection.

Opportunistic infections caused by Pseudomonas aeruginosa can be acute or chronic. While acute infections often spread rapidly and can cause tissue damage and sepsis with high mortality rates, chronic infections can persist for weeks, months, or years in the face of intensive clinical intervention. Remarkably, this diverse infectious capability is not accompanied by extensive variation in genomic content, suggesting that the genetic capacity to be an acute or a chronic pathogen is present in most P. aeruginosa strains. To investigate the genetic requirements for acute and chronic pathogenesis in P. aeruginosa infections, we combined high-throughput sequencing-mediated transcriptome profiling (RNA-seq) and genome-wide insertion mutant fitness profiling (Tn-seq) to characterize gene expression and fitness determinants in murine models of burn and non-diabetic chronic wound infection. Generally we discovered that expression of a gene in vivo is not correlated with its importance for fitness, with the exception of metabolic genes. By combining metabolic models generated from in vivo gene expression data with mutant fitness profiles, we determined the nutritional requirements for colonization and persistence in these infections. Specifically, we found that long-chain fatty acids represent a major carbon source in both chronic and acute wounds, and P. aeruginosa must biosynthesize purines, several amino acids, and most cofactors during infection. In addition, we determined that P. aeruginosa requires chemotactic flagellar motility for fitness and virulence in acute burn wound infections, but not in non-diabetic chronic wound infections. Our results provide novel insight into the genetic requirements for acute and chronic P. aeruginosa wound infections and demonstrate the power of using both gene expression and fitness profiling for probing bacterial virulence.

Empiric evidence for a genetic contribution to predisposition to surgical site infection.

The genetics of microbial pathogens have been extensively studied, but there has been little work on human genetic susceptibility to surgical site infection (SSI). We analyzed a large genealogical population database to study the familial contribution to SSI. We analyzed 651 individuals with International Classification of Disease, Ninth Revision codes indicating the presence of SSI. Matched hospital controls were randomly selected from the database based on birth year, sex, and birthplace. The average relatedness of all possible pairs of cases and separately of controls (×1000 sets) was compared empirically. The relative risk (RR) for SSI was estimated by comparing the number of observed affected individuals among the relatives of cases to the number of affected individuals observed among relatives of matched hospital controls. The genealogical index of familiality test for patients with SSI showed significant excess relatedness (p < 0.010); this excess was still observed when close relationships were ignored (p = 0.019). The RR for third-degree relatives of cases was significantly elevated (1.62, p = 0.029). The significant excess relatedness and the significantly elevated RR to distant relatives support a genetic predisposition to acquiring SSI.

Insertion/deletion polymorphism of the angiotensin-converting enzyme considerably changes postoperative outcome.

STUDY OBJECTIVE: To evaluate the influence of insertion/deletion (ID) polymorphism of the angiotensin-converting enzyme (ACE) gene on clinical outcome of cardiac valve surgery. DESIGN: Prospective, blinded observational study. SETTING: Operating room and intensive care unit (ICU) of a university hospital. PATIENTS: 110 adult patients requiring elective cardiac valve surgery requiring cardiopulmonary bypass. MEASUREMENTS: Patients' preoperative data (age, gender, body weight, New York Heart Association score, medication, biochemical data, and comorbid disorders), anesthetic management (blood pressure, heart rate, blood loss and transfusion, and cardiorespiratory complications and their treatment), and postoperative outcome (life-threatening complications, nosocomial infections, reintubation/reoperation, death, and duration of ICU stay and hospitalization) were recorded. ACE ID was detected by gel electrophoresis following conventional polymerase chain reaction. Patients were divided into two groups postoperatively; groups with II and non-II (ID and DD) genotypes, and group differences were analyzed. MAIN RESULTS: Distribution of ACE ID in II, ID, and DD genotypes was 29%, 59%, and 12%, respectively. The non-II group had significantly greater postoperative blood loss and transfusion (P < 0.05), more common postoperative infections, and longer ICU stay duration than the II group (P < 0.01). CONCLUSIONS: ACE ID polymorphism is associated with a higher incidence of postoperative complications, including postoperative infections, in patients undergoing cardiac valve surgery.

CMY-42, a novel plasmid-mediated CMY-2 variant AmpC beta-lactamase.

We isolated a clinical Escherichia coli strain with an antimicrobial resistance phenotype characteristic for the expression of an AmpC beta-lactamase. Molecular methods revealed a novel, plasmid-localized variant of CMY-2 with a substitution of valine 231 for serine (V231S), which was designated CMY-42. Like the CMY-2-like AmpC beta-lactamase CMY-30, carrying the substitution V231G, CMY-42 displayed increased activity toward expanded spectrum cephalosporins. This finding supports the hypothesis that a bulky side chain at position 231 (Ambler's position 211) may pose a steric clash with certain cephalosporins hindering the access of the AmpC beta-lactamase; however, additional phenomena may account for the observed hydrolytic properties.

Expression of antimicrobial peptides in cutaneous infections after skin surgery.

BACKGROUND: Increasing numbers of antibiotics have lost efficiency because of bacterial resistance. The consequences can be severe when surgical wounds become infected during postoperative care. Natural peptide antibiotics, the so-called host defence peptides (HDPs), have been investigated since the 1990s in a search for alternative treatment strategies. HDPs build up a protection shield against pathological microorganisms, especially in human epithelium. The use of HDPs is currently being discussed as a new antimicrobial therapeutic strategy. Accordingly, a profound knowledge of the quantitative relationships of the effectors is essential. OBJECTIVES: To evaluate differences in HDP expression between postoperatively inflamed and healthy epithelium. METHODS: Expression profiles of the genes encoding HDP human beta-defensin (hBD)-1 (DEFB1, previously known as HBD-1), hBD-2 (DEFB4A, previously known as HBD-2), hBD-3 (DEFB103A, previously known as HBD-3) and psoriasin (S100A7) were assessed in samples of surgical wound healing disorders (n = 27) and healthy epithelium (n = 16) by using real-time polymerase chain reaction. Immunohistochemical staining was performed in the same samples. RESULTS: A significant overexpression of DEFB4A (P < 0.001), DEFB103A (P = 0.001) and S100A7 (P < 0.001) was found in cutaneous surgical site infections. Immunohistochemistry revealed intensely elevated protein levels of psoriasin in infected wounds, and differences in distribution with respect to the epithelial layers. CONCLUSIONS: The study demonstrates upregulated mRNA expression and protein levels of HDPs in postoperatively inflamed epithelium. The results may be a starting point for novel pharmacological treatments.

Alloanti-c in a c-positive, JAL-positive patient.

BACKGROUND AND OBJECTIVES: In the Rh blood group system, partial D, C, and e antigens are well-known, but a partial c antigen resulting in the production of alloanti-c in a c+ individual is rare. One example of an alloanti-c in a c+ person was an anti-Rh26, which can appear as anti-c, and another was an alloanti-c in a c+ person with a presumed R(1)r phenotype. The finding of an apparent alloanti-c in a transfused c+ patient initiated this investigation. MATERIALS AND METHODS: Haemagglutination tests, DNA extraction, polymerase chain reaction (PCR)-based assays (PCR-restriction fragment length polymorphism, allele-specific PCR), reticulocyte mRNA extraction, reverse transcriptase (RT)-PCR and sequencing were performed by standard procedures. RESULTS: Plasma from a 64-year-old African American woman with a wound infection following a mastectomy contained anti-E, anti-S, anti-K, anti-Fy(a) and anti-Jk(b), reacting by the indirect antiglobulin test. In addition, the patient's plasma gave reactions that were consistent with an anti-c, while her pre-transfusion red blood cells typed c+ with some anti-c reagents. These results are consistent with a partial c antigen. The patient's red blood cells also typed V+(W)VS- and JAL+. Analyses of DNA and Rh-transcripts from this patient showed the presence of the following genes: RHD*D, RHD*DAU0, RHCE*Ce and RHCE*ce(S)(340). CONCLUSION: The nucleotide 340C>T change in RHCE exon 3 (predicted to encode 114Trp) of the RHCE*ce(S)(340) allele is associated with a JAL+ phenotype and the altered expression of the c, V and VS antigens. This alteration in the c antigen allowed the patient to make an alloanti-c. This case reveals that the RHCE*ce(S)(340) allele encodes a partial c antigen.

Deoxyribonucleic acid fingerprinting in an outbreak of Staphylococcus aureus intracranial infection after neurotologic surgery.

BACKGROUND: Meningitis is the most common life-threatening infection occurring as an early postoperative complication of neurotologic surgery. From January to March 2001, Staphylococcus aureus intracranial infection developed in three patients; two cases were consecutive. METHODS: All staff members involved in surgery on any of the three patients had nasal swabs for S. aureus. The three patient isolates and all S. aureus isolates from staff members were typed by pulsed-field gel electrophoresis. Operating room procedures were reviewed. RESULTS: All three patient isolates were identical by pulsed-field gel electrophoresis. Six staff members (40%) were found to be S. aureus carriers. The isolate from one staff members was identical to the patient isolates. A procedure audit of the operating room revealed several breaks in recommended practice. The staff carrier was immediately removed from patient care duties, given decolonization therapy, and treated for chronic rhinosinusitis. Practice changes in the operating room were implemented. CONCLUSIONS: S. aureus remains a common cause of surgical site infections. S. aureus carriage is common, and carriers with intercurrent respiratory infections have increased shedding and are a higher risk to patients. Proper use of barrier devices and consistent hand hygiene reduce bacterial contamination of the wound. Current operating room technology involves technical personnel not traditionally trained in operating room procedures. Epidemiologic investigation may be delayed if operating room records are incomplete with respect to these personnel. Molecular typing of bacterial isolates can identify common source outbreaks and effectively focus investigations.

Multiplex PCR assays for the detection of clinically relevant antibiotic resistance genes in staphylococci isolated from patients infected after cardiac surgery. The ESPRIT Trial.

Multiresistant staphylococci (82 Staphylococcus aureus and 114 coagulase-negative staphylococci) were characterized by testing with rapid multiplex polymerase chain reaction (PCR) assays for species identification and detection of associated antibiotic resistance genes. These 196 staphylococci were isolated from 149 adult patients who developed wound infection after elective coronary artery bypass grafts and/or valve surgery. The multiplex PCR assays allowed identification of the most common staphylococcal species with S. aureus- and Staphylococcus epidermidis-specific primers as well as the detection of the erythromycin resistance genes ermA, ermB, ermC and msrA, the aminoglycoside resistance gene aac(6')-aph(2"), the oxacillin resistance gene mecA and the penicillin resistance gene blaZ. There was a very good correlation between the genotypic analysis by PCR and the phenotype determined by standard methods of susceptibility testing and identification of staphylococcal species: 100% for erythromycin resistance, 98.0% for gentamicin resistance, 99.0% for oxacillin resistance, 100% for penicillin resistance and 100% for S. aureus and S. epidermidis species identification. This study suggests that the incidence and distribution of the tested clinically relevant antibiotic resistance genes in staphylococci associated with infections after cardiac surgery do not differ from those in strains from other infections. These multiplex PCR assays may be used as diagnostic tools to replace or complement standard methods of susceptibility testing and identification of staphylococci.

Inducible nitric oxide synthase transcription in human lung transplantation.

BACKGROUND: Recent animal data suggest that inducible nitric oxide synthase (iNOS) mRNA expression in the bronchoalveolar lavage (BAL) may be useful for the diagnosis of lung rejection. The aim of this study was to evaluate iNOS mRNA transcription in the BAL fluid of human lung allografts. METHODS: iNOS mRNA transcription was quantified by competitive reverse transcription-polymerase chain reaction in 51 BAL cell pellets of lung transplant patients. According to bacteriological and histological results, BAL samples were divided into three groups: normal (n=21), acute rejection (AR, n=15), and infection (INF, n=15). RESULTS: Compared with the control group, iNOS transcription increased significantly with INF (P=0.0005) but only slightly with AR (P>0.05). INF values were significantly higher than AR values (P=0.0029). CONCLUSION: BAL iNOS mRNA transcript determination by competitive reverse transcription-polymerase chain reaction may be useful in differentiating infected from normal and/or acutely rejecting allografts.

[Association of tumor necrosis factor microsatellite polymorphism with incidence and outcome of severe postoperative sepsis].

OBJECTIVE: To investigate whether tumor necrosis factor (TNF) microsatellite polymorphism within the TNF locus is associated with the incidence and outcome of severe postoperative sepsis. METHODS: 122 patients with severe postoperative sepsis were included in this study; 138 local ethnically matched healthy individuals served as controls. Microsatellite TNFc polymorphism within the TNF locus was typed using polymerase chain reaction (PCR) followed by polyacrylamide gel electrophoresis with silver staining. RESULTS: Microsatellite TNFc polymorphism had two alleles (TNFc1 and TNFc2) and three kinds of genotype (homozygotes TNFc1c1 and TNFc2c2, and heterozygote TNFc1c2). The genotype distribution fit Hardy-Weinberg equilibrium. The frequency of TNFc1 microsatellite allele was significantly higher in patients with severe sepsis (79%) than in healthy individuals (71%) (P < 0.05). The frequency of heterozygote TNFc1c2 was significantly higher in non-surviving patients (46%) with severe sepsis than in survivors (27%) (P < 0.05). CONCLUSIONS: TNFc microsatellite polymorphism is significantly associated with the incidence and outcome of severe postoperative sepsis.