Transposition of greater omentum in deep sternal wound infection caused by methicillin-resistant Staphylococci, with differing clinical course for MRSA and MRSE.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) and Staphylococcus epidermidis (MRSE) are an increasing problem in deep sternal wound infections (DSWI) after cardiac surgery. METHODS: Between 2005 and 2009, recalcitrant methicillin-resistant Staphylococcus was found in 21 patients with complicated DSWI, and a transposition of the greater omentum (TGO) was finally performed. A positive microbial culture at the time of procedure was present in all patients. The hospital course was reviewed discretely for MRSA and MRSE. RESULTS: Median patient age was 72.3 years (range 60.8-79.7); 76 % of patients were male. Time from the first sternal revision until consecutive open wound therapy due to re-infection and total hospital stay was longer for MRSA compared to MRSE (38 vs. 14 days, P = 0.003, and 141 vs. 91 days, P = 0.007, respectively). The period from cardiac surgery to TGO was likewise prolonged for MRSA (78 vs. 55 days, P = 0.045), whereas in-hospital mortality and one-year mortality rate did not differ. CONCLUSION: TGO remains a good treatment option for DSWI type IV. Microbial findings determine the clinical course; nevertheless in-hospital mortality remains low for both MRSA and MRSE infection.

Minimally invasive partial inferior sternotomy for congenital heart defects in children.

AIM: Minimally invasive approaches for repair of congenital heart defects have gained in popularity. Aim of the study was to evaluate the safety and efficiency of the partial inferior sternotomy approach to repair various congenital heart defects. METHODS: Since 1998, 100 children (55 males; mean age: 3.8 ± 3.7; mean weight: 15.1 ± 8.7 kg) were operated on via a limited median vertical skin incision and partial inferior sternotomy. Preoperative diagnoses were: ASD II (N.=46), sinus venosus defect with partial anomalous pulmonary venous connection (N.=12), partial AV-canal (N.=4), VSD (N.=35), tetralogy of Fallot (N.=2), and double chambered right ventricle (N.=1). Cannulation was always performed via the chest incision. RESULTS: There were no deaths. Mean cross-clamp time was 49.9 ± 30.6 minutes, and mean operation time 192 ± 46 minutes. Mean postoperative mechanical ventilation time, Intensive Care Unit stay and hospital stay were 9.7 ± 10.4 hours, 1.8 ± 0.7 days, and 12 ± 3.0 days, respectively. Complications included pneumothorax requiring drainage in 2 patients, atrioventricular block necessitating a permanent pacemaker in 1 patient. The incisions healed properly. All patients are in excellent condition after a mean follow-up of 32 ± 25 months. On echocardiography no residual defect was evident in 98 patients, and a mild mitral insufficiency in two patients operated on partial atrioventricular canal. CONCLUSION: The partial inferior sternotomy approach to congenital heart operations is less invasive than and cosmetically superior to full sternotomy with reduced postoperative pain and discomfort for the patients. This approach ensures a safe procedure with excellent exposure without additional incisions. It is our standard approach in infants/children with septal defects.

Clinical relevance of eNOS T-786C polymorphism for hospital mortality and morbidity in cardiac surgical patients.

AIM: The endothelial nitric oxide (eNOS) gene T-786C polymorphism may influence as a genetic risk factor cardiovascular diseases and shows association with cardiovascular mortality. We hypothesized that this polymorphism may lead to increase mortality and morbidity after cardiac surgery with cardiopulmonary bypass (CPB). METHODS: In 500 patients who underwent cardiac surgery with CPB we investigated the eNOS T-786C polymorphism by DNA-sequencing. The patients were grouped according to their genotype in three groups (TT, TC, and CC). RESULTS: The overall genotype distribution of T-786C polymorphism was TT=41.6%, TC=51.2%, and CC=7.2% respectively. The groups did not differ in age and gender. No significance was shown in preoperative risk factors, excluding peripheral disease (P=0.03). No difference was shown in Euroscore, APACHE II, and SAPS II. The usage of norepinephrine (P=0.03) and nitroglycerine (P=0.01) was significant higher in TC allele carrier. The mortality was quite uniform across elective and urgent subgroup. However, we found a significant difference concerning mortality and emergency cardiac procedures in homozygous C-allele carrier (P=0.014). CONCLUSION: The present study demonstrates that this polymorphism contributes to a higher prevalence of postoperative mortality after emergency cardiac surgery. Thus, the eNOS T-786C polymorphism could serve as a possibility to differentiate high risk subgroups in heterogeneous population of individuals with cardiac diseases who need cardiac surgery with CPB.

Periodontal bacteria DNA findings in human cardiac tissue - Is there a link of periodontitis to heart valve disease?

BACKGROUND: The aim of the study was to detect periodontal pathogens DNA in atrial and myocardial tissue, and to investigate periodontal status and their connection to cardiac tissue inflammation. METHODS: In 30 patients, biopsy samples were taken from the atrium (A) and the ventricle myocardium (M) during aortic valve surgery. The dental examination included the dental and periodontal status (PS) and a collection of a microbiological sample. The detection of 11 periodontal pathogens DNA in oral and heart samples was carried out using PCR. The heart samples were prepared for detecting the LPS-binding protein (LBP), and for inflammation scoring on immunohistochemistry (IHC), comprising macrophages (CD68), LPS-binding protein receptor (CD14), and LBP (big42). RESULTS: 28 (93%) patients showed moderate to severe periodontitis. The periodontal pathogens in the oral samples of all patients revealed a similar distribution (3-93%). To a lesser extent and with a different distribution, these bacteria DNA were also detected in atrium and myocardium (3-27%). The LBP was detected in higher amount in atrium (0.22±0.16) versus myocardium (0.13±0.13, p=0.001). IHC showed a higher inflammation score in atrial than myocardial tissue as well as for CD14, CD68 and for LBP. Additional, periodontal findings showed a significant correlation to CD14 and CD68. CONCLUSION: The results provide evidence of the occurrence of oral bacteria DNA at the cardiac tissue, with a different impact on atrial and myocardial tissue inflammation. Influence of periodontal findings was identified, but their relevance is not yet distinct. Therefore further clinical investigations with long term implication are warranted.

The effects of residual pump blood on patient plasma free haemoglobin levels post cardiac surgery.

At the end of cardiopulmonary bypass, there are invariably several hundred millilitres of residual pump blood in the reservoir, which can either be re-transfused or discarded. The objective of this prospective observational study was to investigate the quality of the residual pump blood, focusing on plasma free haemoglobin (pfHb) and blood cell counts. Fifty-one consecutive patients were included in the study. Forty-nine units of residual pump blood and 58 units of transfused red blood cell (RBC) concentrates were analysed. The mean preoperative pfHb of the patients was 0.057 ± 0.062 g/l, which increased gradually to 0.55 ± 0.36 g/l on arrival in the intensive care unit postoperatively. On the first postoperative day, the mean pfHb had returned to within the normal range. Our data showed that haemoglobin, haematocrit, and erythrocyte counts of residual pump blood were approximately 40% of the values in standardised RBC concentrates. Plasma free haemoglobin was significantly higher in residual pump blood compared to RBC concentrates, and nearly twice as high as the pfHb in patient blood samples taken contemporaneously. Our findings indicate that residual pump blood pfHb levels are markedly higher compared to patients' blood and RBC concentrates, but that its administration does not significantly increase patients' pfHb levels.

Reduced number of CD1a+ cells in cutaneous B-cell lymphoma.

Cutaneous B-cell lymphoma is difficult to distinguish from pseudolymphoma. The histologic pattern and monoclonal restriction (immunohistochemical analysis and molecular biology) are the criteria used for differentiating these entities. CD1a+ dendritic cells have been observed in the infiltrates of T-cell lymphoma, but the presence of these CD1a+ cells has not been compared in B-cell lymphoma and pseudolymphoma. We studied the presence of CD1a+ cells on frozen sections of 23 B-cell lymphomas, 13 pseudolymphomas, and 17 T-cell lymphomas by immunohistochemical analysis. We found abundant CD1a+ dendritic cells in only 1 (4%) of 23 B-cell lymphomas, whereas in 8 (62%) of 13 pseudolymphomas and 17 (100%) of 17 T-cell lymphomas, strong CD1a staining was present. Our study demonstrates a distinct pattern of CD1a staining in the infiltrates of B-cell lymphoma and pseudolymphoma that may be of value in the differential diagnosis of these skin disorders.

Dielectric resonator-based flow and stopped-flow EPR with rapid field scanning: A methodology for increasing kinetic information.

We report methodology which combines recently developed dielectric resonator-based, rapid-mix, stopped-flow EPR (appropriate for small, aqueous, lossy samples) with rapid scanning of the external (Zeeman) magnetic field where the scanning is preprogrammed to occur at selected times after the start of flow. This methodology gave spectroscopic information complementary to that obtained by stopped-flow EPR at single fields, and with low reactant usage, it yielded more graphic insight into the time evolution of radical and spin-labeled species. We first used the ascorbyl radical as a test system where rapid scans triggered after flow was stopped provided "snapshots" of simultaneously evolving and interacting radical species. We monitored ascorbyl radical populations either as brought on by biologically damaging peroxynitrite oxidant or as chemically and kinetically interacting with a spectroscopically overlapping nitroxide radical. In a different biophysical application, where a spin-label lineshape reflected rapidly changing molecular dynamics of folding spin-labeled protein, rapid scan spectra were taken during flow with different flow rates and correspondingly different times after the mixing-induced inception of protein folding. This flow/rapid scan method is a means for monitoring early immobilization of the spin probe in the course of the folding process.

[Diabetes increases short- and long-term mortality after transcatheter aortic valve implantation (TAVI)]. / Diabetes mellitus erhöht die eingriffsbedingte und die langfristige Mortalität nach kathetergestützter Aortenklappenimplantation.

BACKGROUND AND AIM: Long-term mortality after transcatheter aortic valve implantation (TAVI) in elderly patients with abundant comorbidities is considerable. We aimed to determine the impact of diabetes on short- and long-term mortality after TAVI. METHODS: Our study includes 300 consecutive patients (mean age, 82 ± 5 years) who underwent TAVI (158 transapical, 142 transfemoral procedures). All patients were followed by regular telephone contacts. 36% suffered from diabetes. RESULTS: Diabetes could be identified as significant predictor of short- and long-term mortality after TAVI. In diabetic patients, 30-day-mortality was 2,5 fold elevated (18.3% vs. 7.3%, p = 0.004). Furthermore, they were at significantly higher risk of peri-interventional stroke (p = 0.04), stage 3 acute kidney injury (p = 0.003), and prolonged ventilation (p = 0.01). Even after successful TAVI and discharge from hospital, long-term mortality was significantly elevated in diabetic patients (56% vs. 30%, p < 0.0001). Of note, 25% of diabetic vs. only 8% of non-diabetic patients died from cardiac causes during follow-up, suggesting that TAVI is not able to reduce cardiac-related mortality risk in diabetic patients to the same extent as in non-diabetics. CONCLUSION: Diabetes represents a powerful predictor of adverse early and late outcome after TAVI. These findings should be incorporated into the assessment of the risk-to-benefit ratio of TAVI in diabetic patients.

[Detection of Chlamydia trachomatis in routine clinical practice: increased sensitivity of cell culture in comparison with the microimmunofluorescence test]. / Nachweis von Chlamydia trachomatis in der klinischen Routine: höhere Sensitivität der Zellkultur gegenüber dem Mikroimmunfluoreszenztest.

Recently, direct immunofluorescence staining has been reported as a new tool for detection of Chlamydia trachomatis. This assay is based on monoclonal antibodies directed against a protein present in all serological variations of Chlamydia known to date. In order to evaluate whether immunofluorescence staining could substitute for the time-consuming, expensive tissue culture technique, urethral and cervical swabs of 131 patients treated for sterility were examined for infection with Chlamydia by both methods. The tissue culture technique, based on cultivation of Chlamydia in mammalian cells, was regarded as 100% sensitive and specific. Employing this method, we demonstrated infection with Chlamydia in 20 patients (15.3%). Colonization of both, cervix and urethra was found in 11.5%, whereas solitary colonization of cervix and urethra was found in 2.3 and 1.5% respectively. However, the immunofluorescence assay applied ("Micro-Trak", Syva Company) showed positive results in only 6 out of 20 cases as determined by tissue culture, thus yielding a sensitivity of 30%. Out of 111 patients with negative results in the tissue culture, 108 were detected by immunofluorescence staining, amounting to a specificity of 97.3%. With special regard to the low sensitivity of the direct immunofluorescence assay, our results indicate a superior, yet unequalled role of the tissue culture technique for detection of Chlamydia trachomatis.

Spectroscopic, kinetic, and electrochemical characterization of heterologously expressed wild-type and mutant forms of copper-containing nitrite reductase from Rhodobacter sphaeroides 2.4.3.

We report the development of a high-yield heterologous expression system for the copper-containing nitrite reductase from a denitrifying variant of Rhodobacter sphaeroides. Typical yields of wild-type protein are 20 mg L-1, which can be fully loaded with copper. Nitrite reductase contains an unusual blue-green Type 1 copper center with a redox/electron transfer function and a nearby Type 2 center where nitrite binds and is reduced to nitric oxide. The wild-type enzyme was characterized by: (1) its blue-green Type 1 optical spectrum; (2) its EPR spectrum showing rhombic character to its Type 1 center and nitrite perturbation to its Type 2 center; (3) its 247-mV Type 1 midpoint potential which is low relative to other Type 1 centers; and (4) its kinetics as measured by both steady-state and stopped-flow methods. The Type 2 copper reduction potential as monitored by EPR in the absence of nitrite was below 200 mV so that reduction of the Type 2 center by the Type 1 center in the absence of nitrite is not energetically favored. The mutation M182T in which the methionine ligand of Type 1 copper was changed to a threonine resulted in a blue rather than blue-green Type 1 center, a midpoint potential that increased by more than 100 mV above that of the wild-type Type 1 center, and a somewhat reduced nitrite reductase activity. The blue color and midpoint potential of M182T are reminiscent of plastocyanin, but the Type 1 cupric HOMO ground-state electronic g value and copper hyperfine properties of M182T (as well as cysteine and histidine ENDOR hyperfine properties; see next paper) were unchanged from those of the blue-green native Type 1 center. His287 is a residue in the Type 2 region whose imidazole ring was thought to hydrogen bond to the Type 2 axial ligand but not directly to Type 2 copper. The mutation H287E resulted in a 100-fold loss of enzyme activity and a Type 2 EPR spectrum (as well as ENDOR spectra; see next paper) which were no longer sensitive to the presence of nitrite.