[Is the discipline associated with self-confidence in handling rational antibiotic prescription? : Results from the MR2 study in German hospitals]. / Ist die Fachrichtung assoziiert mit der Selbstsicherheit im Umgang mit rationaler Antibiotikaverordnung? : Ergebnisse der MR2-Studien an deutschen Kliniken.

BACKGROUND: Besides public awareness and specialist knowledge and training of physicians, their self-confidence plays a key role for clinical decision-making in the respective area. OBJECTIVE: This exploratory study investigated the influence of the discipline on differences in self-confidence in dealing with antibiotics and in the self-rated knowledge. METHODS: In 2015 the multi-institutional reconnaissance of practice with multiresistant bacteria (MR2) questionnaire containing items on antibiotic prescription and multiresistant pathogens was sent out to 1061 physicians working in departments for internal medicine, general surgery, gynecology and obstetrics and urology. In 2017 a similar MR2 survey was sent to 1268 specialist and assistant physicians in anesthesiology in Germany. Besides demographic data 4 items on self-confidence in the use of antibiotic treatment and 11 items concerning self-rated knowledge about rational antibiotic therapy and multiresistant pathogens were included in the present analysis. Logistic regression analysis, the χ2-test and the Kruskal-Wallis test were used for statistical analysis of the influence of the discipline on these items. RESULTS: The response rates were 43% (456 out of 1061) from the non-anesthetists and 56% (705 out of 1268) from the anesthetists. Of the non-anesthetists 44% and 57% of the anesthetists had had no advanced training on antibiotic stewardship during the year before the study. In the overall analysis anesthetists (mean±SD: 2.53±0.54) were significantly less self-confident about antibiotics than colleagues from other departments (internal medicine: 3.10±0.50, general surgery: 2.97±0.44, gynecology and obstetrics: 3.12±0.42 and urology: 3.15±0.44) in the unadjusted (all p<0.001) and adjusted comparison. The analysis of self-rated knowledge about rational antibiotic prescription showed similar results. Senior consultant status and advanced training in infectiology were significantly associated with self-confidence and self-rated knowledge about antibiotics. CONCLUSION: Anesthetists showed significantly less self-confidence in dealing with antibiotics than colleagues from other disciplines. Advanced training on a rational prescription of antibiotics was associated with a greater self-confidence, so that the implementation of compulsory courses on rational antibiotic stewardship in the respective residency curriculum needs to be considered.

Longitudinal analysis of cartilage T2 relaxation times and joint degeneration in African American and Caucasian American women over an observation period of 6 years - data from the Osteoarthritis Initiative.

OBJECTIVES: To investigate the change in cartilage T2 values and structural degeneration in knee joints over 72 months in women of African American (AA) vs Caucasian American (CA) ethnicity. METHODS: Knee 3T magnetic resonance imaging (MRIs) from baseline, 24, 48 and 72 months visits of 100 AA and 100 CA women from the Osteoarthritis Initiative (OAI) were assessed for cartilage T2 values and whole-organ magnetic resonance imaging (WORMS) score. Subjects were pair-matched by age, body mass index (BMI), Kellgren-Lawrence (KL) score, clinical site and subcohort within the OAI. We compared the rate of change in whole knee cartilage T2 values and WORMS cartilage, bone marrow edema pattern (BMEP) and meniscus scores between the two ethnic groups using mixed random effects models. RESULTS: At 24 and 48 months 60 subjects and at 72 months 45 subjects per group were available for analysis resulting in 38 complete pairs with data of all time points. Compared to CA, cartilage T2 values in AA increased at a significantly faster rate at baseline (AA: 0.45 ms/y, CA: 0.35 ms/y, P = 0.029) and averaged over 6 years (AA: 0.36 ms/y, CA: 0.27 ms/y, P = 0.039) with changes in both groups reaching a plateau by 48 months. Cartilage, meniscus and BMEP scores tended to increase in both groups during follow up, but rates of change did not differ by ethnicity. CONCLUSION: Cartilage T2 values increased faster over 72 months in AA than CA, however changes in WORMS cartilage, meniscus and BMEP scores did not differ. T2 values may be able to distinguish ethnicity-related differences of cartilage degeneration at an early stage before differences in structural joint degeneration appear.

The association between MR T1ρ and T2 of cartilage and patient-reported outcomes after ACL injury and reconstruction.

OBJECTIVE: To determine if cartilage T1ρ and T2 relaxation time measures after ACL injury and prior to reconstruction (baseline) are associated with patient-reported outcomes at baseline, 6-months, and 1-year after surgery. DESIGN: Fifty-four ACL-injured participants were scanned in both knees at baseline using 3T MR T1ρ and T2 mapping. Participants also completed Knee-injury and Osteoarthritis Outcome Score (KOOS) and Marx activity level questionnaires at baseline, 6-months, and 1-year after reconstruction. The difference between cartilage T1ρ or T2 of the injured and contralateral knee (side-to-side difference, SSD) was calculated to account for physiological variations among patients. Linear regression models were built to evaluate the association between the baseline SSD T1ρ or T2 and KOOS or Marx at all time points. RESULTS: Higher baseline SSD T1ρ posterolateral tibia (pLT) was associated with worse KOOS in all subscales except symptoms at baseline, worse KOOS pain at 6-months, and worse KOOS in all subscales except sports function at 1-year. Higher baseline SSD T2 femoral trochlea (TrF) was associated with worse KOOS activities of daily living (ADL) at 1-year. Higher baseline SSD T1ρ pLT was associated with lower Marx activity level at 1-year. More severe cartilage lesions, as assessed by Whole-Organ MRI Scoring (WORMS), was significantly associated with worse KOOS pain at 6-months and 1-year. CONCLUSION: T1ρ and T2 of cartilage after ACL injury were associated with KOOS after injury and both KOOS and Marx after reconstruction. Such associations may help clinicians stratify outcomes post-injury, and thus, improve patient management.

Association between cartilage degeneration and subchondral bone remodeling in patients with knee osteoarthritis comparing MRI and (99m)Tc-DPD-SPECT/CT.

OBJECTIVE: The purpose of this retrospective cross-sectional study was to investigate the association between cartilage lesions assessed with 3T-MRI and remodeling of the subchondral bone detected by (99m)Tc-DPD-SPECT/CT. DESIGN: (99m)Tc-DPD-SPECT/CT and MRI of 27 knees of 25 patients with chronic knee pain and risk factors for osteoarthritis (OA) were evaluated by one nuclear physician and one radiologist. Six regions of the knee (in total 162 regions in 27 knees) were assessed according to structural joint lesions graded with a modified Whole Organ MR imaging score (WORMS) and according to subchondral (99m)Tc-DPD-SPECT uptake. Relationships between regional WORMS scores and uptake were quantified using general estimating equations. In a secondary analysis the uptake sum with the WORMS sum per joint was compared using Spearman correlations. RESULTS: Elevated subchondral uptake was significantly associated with the grade of cartilage lesions (P < 0.0001). Mean uptake was significantly higher subjacent to full thickness cartilage lesions compared to partial thickness lesions (P < 0.0001). A similar association was observed between bone marrow edema pattern (BMEP) and cartilage lesions. The sum of uptakes per joint was positively correlated to the WORMS sum (rs = 0.42) and to the sum of cartilage lesions per joint (rs = 0.50). CONCLUSION: Both functional and structural changes of the subchondral bone in terms of scintigraphic osseous activity and the presence and degree of BMEP were significantly associated with cartilage lesions in patients with OA of the knee. This association was pronounced with full thickness lesions, indicating a possible protective effect of the cartilage layer for the subjacent bone.

Association of Physical Activity Measured by Accelerometer, Knee Joint Abnormalities, and Cartilage T2 Measurements Obtained From 3T Magnetic Resonance Imaging: Data From the Osteoarthritis Initiative.

OBJECTIVE: To study the cross-sectional association between physical activity measured with an accelerometer, structural knee abnormalities, and cartilage T2 values assessed with 3T magnetic resonance imaging (MRI). METHODS: We included 274 subjects from the Osteoarthritis Initiative cohort without definite radiographic osteoarthritis (Kellgren/Lawrence grades 0 and 1) and with at most mild pain, stiffness, and functional limitation in the study knee (Western Ontario and McMaster Universities Osteoarthritis Index scale 0-1), which had not limited their activity due to knee pain. Physical activity was measured over 7 days with an ActiGraph GT1M accelerometer. Subjects were categorized by quartile of physical activity based on the average daily minutes of moderate to vigorous physical activity (mv-PA). MRI images of the right knee (at 48-month visit) were assessed for structural abnormalities using a modified Whole-Organ Magnetic Resonance Imaging Score (WORMS) and for T2 relaxation times derived from segmented cartilage of 4 femorotibial regions and the patella. WORMS grades and T2 measurements were compared between activity quartiles using a linear regression model. Covariates included age, sex, body mass index, knee injury, family history of knee replacement, knee symptoms, hip and ankle pain, and daily wear time of the accelerometer. RESULTS: Higher mv-PA was associated with increased severity (P = 0.0087) and number of lesions of the medial meniscus (P = 0.0089) and with severity of bone marrow edema lesions (P = 0.0053). No association between cartilage lesions and mv-PA was found. T2 values of cartilage (loss, damage, and abnormalities) tended to be greater in the higher quartiles of mv-PA, but the differences were nonsignificant. CONCLUSION: In knees without radiographic osteoarthritis in subjects with no or mild knee pain, higher physical activity levels were associated with increases in meniscal and bone marrow edema pattern lesions.

Characterization of the collagen component of cartilage repair tissue of the talus with quantitative MRI: comparison of T2 relaxation time measurements with a diffusion-weighted double-echo steady-state sequence (dwDESS).

OBJECTIVES: The purpose of this study was to characterize the collagen component of repair tissue (RT) of the talus after autologous matrix-induced chondrogenesis (AMIC) using quantitative T2 and diffusion-weighted imaging. METHODS: Mean T2 values and diffusion coefficients of AMIC-RT and normal cartilage of the talus of 25 patients with posttraumatic osteochondral lesions and AMIC repair were compared in a cross-sectional design using partially spoiled steady-state free precession (pSSFP) for T2 quantification, and diffusion-weighted double-echo steady-state (dwDESS) for diffusion measurement. RT and cartilage were graded with modified Noyes and MOCART scores on morphological sequences. An association between follow-up interval and quantitative MRI measures was assessed using multivariate regression, after stratifying the cohort according to time interval between surgery and MRI. RESULTS: Mean T2 of the AMIC-RT and cartilage were 43.1 ms and 39.1 ms, respectively (p = 0.26). Mean diffusivity of the RT (1.76 µm(2)/ms) was significantly higher compared to normal cartilage (1.46 µm(2)/ms) (p = 0.0092). No correlation was found between morphological and quantitative parameters. RT diffusivity was lowest in the subgroup with follow-up >28 months (p = 0.027). CONCLUSIONS: Compared to T2-mapping, dwDESS demonstrated greater sensitivity in detecting differences in the collagen matrix between AMIC-RT and cartilage. Decreased diffusivity in patients with longer follow-up times may indicate an increased matrix organization of RT. KEY POINTS: • MRI is used to assess morphology of the repair tissue during follow-up. • Quantitative MRI allows an estimation of biochemical properties of the repair tissue. • Differences between repair tissue and cartilage were more significant with dwDESS than T2 mapping.

The disease burden of hepatitis B, influenza, measles and salmonellosis in Germany: first results of the burden of communicable diseases in Europe study.

Setting priorities in the field of infectious diseases requires evidence-based and robust baseline estimates of disease burden. Therefore, the European Centre for Disease Prevention and Control initiated the Burden of Communicable Diseases in Europe (BCoDE) project. The project uses an incidence- and pathogen-based approach to measure the impact of both acute illness and sequelae of infectious diseases expressed in disability-adjusted life years (DALYs). This study presents first estimates of disease burden for four pathogens in Germany. The number of reported incident cases adjusted for underestimation served as model input. For the study period 2005-2007, the average disease burden was estimated at 33 116 DALYs/year for influenza virus, 19 115 DALYs/year for Salmonella spp., 8708 DALYs/year for hepatitis B virus and 740 DALYs/year for measles virus. This methodology highlights the importance of sequelae, particularly for hepatitis B and salmonellosis, because if omitted, the burden would have been underestimated by 98% and 56%, respectively.

The immune response to one-lung-ventilation is not affected by repeated alveolar recruitment manoeuvres in pigs.

BACKGROUND: Acute lung injury after thoracic surgery relates to alveolar inflammation induced by one-lung ventilation (OLV) and surgical manipulation. However, alveolar recruitment manoeuvres (ARM), conventional ventilation, and airway manipulation may increase alveolar trauma. This study evaluates pulmonary immune effects of these co-factors in a porcine model. METHODS: Twenty-two piglets (27.3 kg) were randomised to spontaneous breathing (N.=4), two-lung ventilation (TLV, N.=6), OLV with propofol (6 mg/kg/h, N.=6) or desflurane anesthesia (1MAC, N.=6). Mechanical ventilation settings were constant throughout the experiment: VT=10 mL/kg, FIO2=0.4, PEEP=5 cmH2O. OLV was performed by left-sided bronchial blockade. Thoracic surgery was simulated for 60 min. ARM (airway pressure of 40 mbar for 10 s) was applied before and after each airway manipulation. Cytokines and mRNA-expression were assessed by immunoassays and semi-quantitative RT-PCR in alveolar lavage fluids, serum and tissue samples prior to and after OLV (TLV in controls). RESULTS: Repetitive ARM and TLV induced no significant proinflammatory effects. OLV enhanced cytokine release but less with desflurane inhalation than propofol infusion (median (IQR) [pg/mL], dependent lung): Interleukin-8: TLV 44 (17) to 68 (35), propofol 82 (17) to 494 (231), desflurane 89 (30) to 282 (44). Likewise, serum cytokines were different: tumour necrosis factor-a: TLV 37 (13) to 62 (7), propofol 55 (39) to 94 (60), desflurane 43 (33) to 41 (25). Expression of interleukin-8-mRNA increased after OLV, but mRNA expression was not modulated by anesthetics. CONCLUSION: ARM, standard TLV and repetitive BAL do not additionally contribute to lung injury resulting from OLV for thoracic surgery in healthy porcine lungs. OLV induces expression of interleukin-8-mRNA in alveolar cells, which is not modulated by different anesthetic drugs.

Estimating the long-term effects of HPV vaccination in Germany.

In Germany, vaccination against the most oncogenic HPV types 16/18 is recommended by the Standing Committee on Vaccination (STIKO) for 12-17 year old girls since March 2007. We developed a dynamic mathematical model for the natural history and transmission of HPV infections to estimate the impact of vaccination on incidence and mortality of cervical cancer and its pre-stages, and on anogenital warts. We focused on an extensive model calibration to epidemiologic data for all stages of the natural history model as well as on a detailed implementation of cervical cancer screening modalities in Germany. Our model predicts first a substantial reduction of cervical cancer incidence and mortality over the next 30 years, which is mainly attributable to an increase in screening participation in the 1990s and not to HPV vaccination, followed by a further reduction attributable to vaccination. Over the next 100 years, HPV vaccination will prevent approximately 37% of cervical cancer cases even if vaccination coverage is only 50% (as currently observed in Germany). Consideration of cross-protection results in a further reduction of approximately 7% of all cervical cancer cases for the bivalent and about 5% for the quadrivalent vaccine in our model. Vaccination of boys was only reasonable if moderate to high vaccination coverage in girls was not achieved. Strategies should be implemented in Germany to increase HPV vaccination coverage among girls thereby making better use of the demonstrated benefits of the vaccine.

Predicting the population impact of chlamydia screening programmes: comparative mathematical modelling study.

BACKGROUND: Published individual-based, dynamic sexual network modelling studies reach different conclusions about the population impact of screening for Chlamydia trachomatis. The objective of this study was to conduct a direct comparison of the effect of organised chlamydia screening in different models. METHODS: Three models simulating population-level sexual behaviour, chlamydia transmission, screening and partner notification were used. Parameters describing a hypothetical annual opportunistic screening program in 16-24 year olds were standardised, whereas other parameters from the three original studies were retained. Model predictions of the change in chlamydia prevalence were compared under a range of scenarios. RESULTS: Initial overall chlamydia prevalence rates were similar in women but not men and there were age and sex-specific differences between models. The number of screening tests carried out was comparable in all models but there were large differences in the predicted impact of screening. After 10 years of screening, the predicted reduction in chlamydia prevalence in women aged 16-44 years ranged from 4% to 85%. Screening men and women had a greater impact than screening women alone in all models. There were marked differences between models in assumptions about treatment seeking and sexual behaviour before the start of the screening intervention. CONCLUSIONS: Future models of chlamydia transmission should be fitted to both incidence and prevalence data. This meta-modelling study provides essential information for explaining differences between published studies and increasing the utility of individual-based chlamydia transmission models for policy making.

[Vaccines against human papillomavirus (HPV); between registration and implementation]. / Vaccins tegen Humaan papillomavirus (HPV); tussen registratie en implementatie.

--Each year, 600-700 women in the Netherlands are diagnosed with cervical cancer. Over the last 10 years, an average of 250 women have died annually due to cervical cancer. --Gardasil, the first vaccine for Human papillomavirus (HPV), was recently approved in Europe for the prevention of cervical cancer. --The availability of a vaccine for HPV prompts the question whether it should be included in the Dutch National Immunisation Programme. --At the end of 2006, the Medicines Evaluation Board, the Health Council of the Netherlands and the Centre for Infectious Disease Control of the National Institute for Public Health and the Environment organised a workshop for experts in the field to answer that question. --The HPV vaccine provides protection against HPV-16 and HPV-18, which cause approximately 70% of cervical cancers. --Because the efficacy of vaccination is only evident after many years, preserving good participation in the screening programme is essential. --The current screening could be improved by introducing an HPV test combined with self-sampling for women who do not participate in screening. --Vaccination is unarguably an important development. However, there are still several unanswered questions regarding vaccination and its actual protection, duration of protection, long-term safety and cost-effectiveness. --April 1st, 2008, the Health Council of the Netherlands had recommended including HPV vaccination in the National Immunisation Programme.

Effects of propofol and desflurane anaesthesia on the alveolar inflammatory response to one-lung ventilation.

BACKGROUND: One-lung ventilation (OLV) induces a pro-inflammatory response including cytokine release and leucocyte recruitment in the ventilated lung. Whether volatile or i.v. anaesthetics differentially modulate the alveolar inflammatory response to OLV is unclear. METHODS: Thirty patients, ASA II or III, undergoing open thoracic surgery were randomized to receive either propofol 4 mg kg(-1) h(-1) (n = 15) or 1 MAC desflurane in air (n = 15) during thoracic surgery. Analgesia was provided by i.v. infusion of remifentanil (0.25 microg kg(-1) min(-1)) in both groups. The patients were mechanically ventilated according to a standard protocol during two-lung ventilation and OLV. Fibre optic bronchoalveolar lavage (BAL) of the ventilated lung was performed before and after OLV and 2 h postoperatively. Alveolar cells, protein, tumour necrosis factor alpha (TNFalpha), interleukin (IL)-8, soluble intercellular adhesion molecule-1 (sICAM), IL10, and polymorphonuclear (PMN) elastase were determined in the BAL fluid. Data were analysed by parametric or non-parametric tests, as indicated. RESULTS: In both groups, an increase in pro-inflammatory markers was found after OLV and 2 h postoperatively; however, the fraction of alveolar granulocytes (median 63.7 vs 31.1%, P < 0.05) was significantly higher in the propofol group compared with the desflurane group. The time courses of alveolar elastase, IL-8, and IL-10 differed between groups, and alveolar TNFalpha (7.4 vs 3.1 pg ml(-1), P < 0.05) and sICAM-1 (52.3 vs 26.3 ng ml(-1), P < 0.05) were significantly higher in the propofol group. CONCLUSIONS: These data indicate that pro-inflammatory reactions during OLV were influenced by the type of general anaesthesia. Different patterns of alveolar cytokines may be a result of increased granulocyte recruitment during propofol anaesthesia.

[Diffuse alveolar hemorrhage (DAH): an underestimated pulmonary complication after hematopoietic stem cell transplantation]. / Diffuse alveoläre Hämorrhagie (DAH): Eine unterschätzte pulmonale Komplikation nach hämatopoetischer Stammzelltransplantation.

Diffuse alvedar haemorrhage (DAH): a severe complication post haematopoietic stemcell transplantation (HSCT) with high mortality. Early diagnose and distinction from other pulmonary complications is essential. Radiologic imaging provides first cues to diagnose. Confirmation of diagnose by BAL. Therapeutic approach with high dose steroids

[Therapy of malignant ascites in vivo by 211At-labelled microspheres]. / Therapie maligner Asziteszellen in vivo mit 211At-markierten Mikrosphären.

AIM: Determination of the biological effect of the alpha emitter (211)At on cellular level as well as the assessment of dosimetric data in a tumour model in vivo. METHODS: Transplantation of malignant ascitic cells in mice intraperitoneally and estimation of tumour characteristics (doubling time of the cells, mean survival of the animals following an i.p. application of a defined tumour cell number). (211)At labelled human serum albumin microspheres B-20 (MSP) of varying activity were injected into tumour bearing mice intraperitoneally. The effectiveness of the therapy was evaluated by means of determination of the duration of cell cycle arrest as well as the microscopic analysis of the rate of abnormal mitotic cells due to radiation induced damage. Furthermore, dose dependence of survival was evaluated. RESULTS: Three days following the intraperitoneally application of 8 x 10(6) tumour cells, 50-600 kBq (211)At-MSP were applied into the abdominal cavity. Considering the volume of ascites at this time and the administered activity, dose calculations were performed. An activity of 50 kBq caused a dose of 0.84 Gy. The increase of radiation induced effect on ascitic tumour cells was correlated with the dose. Between the duration of the cell cycle arrest and the administered activity, a directly proportional correlation was found. The mean survival of non-treated animals was 16.9 +/- 3.7 days. The prolongation of the survival was proportional to the activity administered. Using a dosage of 10 Gy, five animals out of 16 survived. CONCLUSION: Therapy of malignant ascitic cells using (211)At-MSP was effective in vivo. For tumour therapy, the (211)At represents a highly effective alternative to usually applied beta emitters.

[Anesthesiological management of pancreatectomy with curative intention in pancreatic carcinoma]. / Anästhesie und Intensivtherapie bei kurativen Resektionen des Pankreas wegen Karzinom.

Pancreatectomy for pancreatic carcinoma makes high demands on the perioperative anesthesiologic management of these patients. This survey is centered on pathophysiological reflections related to the choice of the anesthesia and accompanying therapy, concerning the pathological mechanisms of intra- and postoperative complications. The influences of the surgical as well as the anesthesiological procedure on the autonomous nervous system and splanchnic blood flow, the organo-specific consequences of the resection and the possible influences on the immune system are discussed. Recommendations for perioperative medical care of these patients are derived from it. Central points are an anesthesiologic management adapted to the patient with regard to pathophysiological changes caused by surgery, monitoring and therapy of the disturbed fluid balance, postoperative intensive care as well as an optimal pain treatment.

[Intraoperative neurolysis of the celiac plexus in patients with unresectable pancreatic cancer]. / Intraoperative Neurolyse des Plexus celiacus bei Patienten mit nichtresektablem Pankreaskarzinom.

BACKGROUND: The analgetic treatment of inoperable pancreatic cancer patients is of paramount importance. The relative ineffectiveness of pharmacological agents has led many investigators to recommend chemical neurolysis of the celiac ganglions for pain control. However, the assessment of the results and the effectiveness of the block carried out during laparotomy have been unclear. PATIENTS AND METHODS: After 41 intraoperative celiac neurolytic blocks pain intensity was retrospectively analysed in 38 patients suffering from unresectable pancreatic carcinoma. The mean age of the patients was 59 years, the observation period after neurolysis ranged to 6 months. All patients underwent definitive neurolysis using 50 % ethanol in 0.5 % prilocaine. Immediate and long-term efficacy, analgetic consumption and mortality were evaluated at follow-up. The calculated parenteral equivalent morphine dosage (mg per day) was evaluated before as well as at different time points after treatment as an objective parameter to describe pain intensity. RESULTS: 7 to 34 days (at discharge from the hospital) after block pain intensity was statistically highly significant reduced (p=0.016). Long-term results were obtained from 17 (10 to 12 weeks after intervention) and 9 (up to 20 weeks after intervention) patients respectively, demonstrating a long-lasting effect of the neurolysis. A statistical analysis was not possible because of the small patient 's number. CONCLUSIONS: Intraoperative celiac neurolytic block is a safe and effective method of pain treatment in patients with unresectable pancreatic carcinoma. However, it alone provides complete pain relief until death only in a few cases. Therefore, it should be considered as an adjuvant treatment in the analgesic strategy. Combined palliative therapy is necessary in most of the cases.

Observation of optical Smith-Purcell radiation at an electron beam energy of 855 MeV.

Smith-Purcell radiation, generated when a beam of charged particles passes close to the surface of a diffraction grating, has been studied in the visible spectral range at wavelengths of 360 and 546 nm with the low emittance 855 MeV electron beam of the Mainz Microtron MAMI. The beam focused to a spot size of 4 microm (full width at half maximum) passed over optical diffraction gratings of echelle profiles with blaze angles of 0.8 degrees, 17.27 degrees, and 41.12 degrees and grating periods of 0.833 and 9.09 microm. Taking advantage of the specific emission characteristics of Smith-Purcell radiation a clear separation from background components, such as diffracted synchrotron radiation from upstream beam optical elements and transition radiation, was possible. The intensity scales with a modified Bessel function of the first kind as a function of the distance between electron beam and grating surface. Experimental radiation factors have been determined and compared with calculations on the basis of Van den Berg's theory [P.M. Van den Berg, J. Opt. Soc. Am. 63, 689 (1973)]. Fair agreement has been found for gratings with large blaze angles while the measurement with the shallow grating (blaze angle 0.8 degrees ) is at variance with this theory. Finally, the optimal operational parameters of a Smith-Purcell radiation source in view of already existing powerful undulator sources are discussed.

Procalcitonin following elective partial liver resection--origin from the liver?

BACKGROUND: The origin of the inflammatory peptide procalcitonin (PCT) is still unknown. In the present study PCT concentrations in arterial and hepatic-venous blood were examined in patients undergoing elective partial liver resection (LR) using a fiberoptic pulmonary arterial catheter placed in a liver vein to obtain further information on the origin of PCT. METHODS: In 28 patients (21 male/7 female; average age of 58.8+/-8.8 years) undergoing LR, arterial and hepatic venous PCT concentrations were measured during 24 h perioperatively. The parallel blood withdrawals occurred immediately before the Pringle maneuver (Hx), 2 min, 1, 2, 6, 12, and 24 h after Hx. Over the whole period, the oxygen saturation in hepatic venous blood (ShvO2) was monitored. PCT concentrations were assayed by immunoluminometry. RESULTS: We observed a significant increase in PCT concentration already 6 h after Hx compared to the values before Hx. Twenty-four hours after Hx we found the highest plasma concentrations. It was conspicuous that hepatic venous PCT concentrations were always higher than the arterial ones (significantly from the 6th hour after Hx). There was no correlation between the courses of ShvO2 and PCT rise. A significant correlation was verified between Hx duration and PCT concentration measured 24 h after Hx both in the hepatic venous and arterial blood. CONCLUSIONS: The results of our investigation can be interpreted as evidence that liver (or the hepatosplanchnicus?) is a source of PCT. The mechanism of PCT induction cannot be clarified by our study: whether the induction of PCT was caused by an endotoxin translocation during the impeded splanchnic outflow or by the direct surgery-induced lesion (hypoxia) of the liver remains unclear. However, the latter appears more probable because of the observed correlation between Hx duration and PCT concentration rise.

[Intraoperative diagnosis of pheochromocytoma preoperative symptoms in a case of Recklinghausen's disease]. / Intraoperative Diagnose eines präoperativ symptomlosen Phäochromozytoms bei Morbus Recklinghausen.

Phaechromocytoma is a rare catecholamine secreting tumor, which occasionally presents as a life threatening crisis in association with surgery and anesthesia. We report a 58-year-old women with known Recklinghausen's disease who was admitted for elective resection of a pancreas tail cystadenoma. A cystadenocarcinoma was taken into account differential diagnostically. No clinical symtoms or signs pointing to a hormone active tumor were found preoperatively. After opening of the abdomen and palpation of the tumor, a hypertensive crisis occurred accompanied by considerable tachycardia, leading to the tentative diagnosis of a phaeochromocytoma in connection to the known phacomatosis. The hypertensive crisis was treated with nitroglycerin and esmolol. The putative tumor of the pancreas represented itself as an adrenal tumor without relationship to the pancreas. Following ligature of the suprarenal vein, antihypertensive therapy could be finished. For stabilization of blood pressure a noradrenaline application was necessary in descending dosage over a period of two days. The further postoperative course was without complications. The results of the urine catecholamine measurements and histological examinations confirmed the intraoperative diagnosis. An unidentified phaeochromocytoma is a vital threat for patients during surgery and anesthesia. Phaeochromocytomas are observed in patients suffering from Recklinghausen's disease (and other phacomatoses) in an above average incidence. Therefore, such a tumor should be excluded in these patients before elective surgery even if the patient does not show symptoms (asymptomatic phaeochromocytomas occur). The determination of catecholamines in 24 hour urine collections is an easy and specific diagnostic procedure and should be used in patients suffering from phacomatoses before elective surgery.