Maxillary advancement versus mandibular setback in class III dentofacial deformity: are there any differences in aesthetic outcomes?

A retrospective evaluation of maxillary advancement and mandibular setback in class III patients was performed and their aesthetic outcomes compared. Patients with a sella-nasion-A-point angle (SNA) of 80-84° were selected. Pre- and postoperative lateral cephalograms were obtained for 34 class III patients; these were divided into two groups according to the surgical procedure performed: mandibular setback group (n=17) and maxillary advancement group (n=17). The pre- and postoperative cervical length, lip-chin-throat angle, lower/upper lip thickness, distance from the lower/upper lip to the aesthetic line, soft tissue angle, facial contour angle, and nasolabial angle of the two groups were compared. Significant differences were observed for cervical length (P=0.0003) and sex (P=0.003) when comparing maxillary advancement with mandibular setback. Although the preoperative cervical length was similar in the two groups, it increased significantly after maxillary advancement and decreased after mandibular setback. In this study, the differences in aesthetic outcomes depending on the surgical procedure performed were considered. Some aesthetically important parameters proved to be superior after maxillary advancement when compared to mandibular setback, even with the maxilla in the normal position.

Disinfection of gloves: feasible, but pay attention to the disinfectant/glove combination.

BACKGROUND: Compliance with hand hygiene is complicated by indications for hand disinfection in rapid succession during the care of one patient. In such situations, disinfection of gloves could facilitate better workflow and optimize compliance rates. AIM: We analysed the efficacy of disinfecting gloves by comparing an individual effect of five different hand disinfectant solutions in combination with three different glove types. METHODS: The investigation was performed in accordance with DIN EN 1500:2013. For all combinations, ten analyses were performed, including (1) right/left-hand examination disinfection efficacy after the first and fifth contamination with E. coli K12 NCTC 10538, (2) recovery rates after contamination, (3) reduction efficacy, (4) fingertip immersion culture, and (5) check for tightness. Disinfection of the ungloved hands was taken as an additional benchmark. FINDINGS: The disinfection efficacy for all disinfectant/glove combinations was better with rather than without gloves. For eight combinations, the disinfection efficacy was always >5.0 log10. There were significant differences within the gloves (P=0.0021) and within the disinfectant product (P=0.0023), respectively. In detail, Nitril Blue Eco-Plus performed significantly better than Vasco Braun (P=0.0017) and Latex Med Comfort (P=0.0493). Descoderm showed a significantly worse performance than Promanum pure (P=0.043). In the check for tightness, only the Vasco Braun gloves showed no leaks in all samples. There were relevant qualitative differences pertaining to the comfort of disinfecting gloves. CONCLUSION: The disinfection efficacy for the different disinfectant/glove combinations was greater than for the ungloved hands. However, various disinfectant/glove combinations produce relevant differences as regards disinfection efficacy.

Good Medicine and Good Healthcare Demand Good Information (Systems).

The demand for evidence-based health informatics and benchmarking of 'good' information systems in health care gives an opportunity to continue reporting on recent papers in the German journal GMS Medical Informatics, Biometry and Epidemiology (MIBE) here. The publications in focus deal with a comparison of benchmarking initiatives in German-speaking countries, use of communication standards in telemonitoring scenarios, the estimation of national cancer incidence rates and modifications of parametric tests. Furthermore papers in this issue of MIM are introduced which originally have been presented at the Annual Conference of the German Society of Medical Informatics, Biometry and Epidemiology. They deal as well with evidence and evaluation of 'good' information systems but also with data harmonization, surveillance in obstetrics, adaptive designs and parametrical testing in statistical analysis, patient registries and signal processing.

Margins of oral leukoplakia: autofluorescence and histopathology.

Autofluorescence devices are widely used to examine oral lesions. The aim of this study was to see whether there were any signs of dysplasia, parakeratosis, or mucosal inflammation in the borders of homogeneous oral leukoplakia using autofluorescence, and we also compared clinically visible extensions with those detected by autofluorescence. Twenty patients with 26 homogeneous areas of oral leukoplakia were included in the study. After the clinically visible extensions of the lesion had been marked, we took a photograph through the autofluorescence device, which showed both borders in one picture. We then used photo-editing software to measure the size of the area of leukoplakia together with the area with loss of autofluorescence. We took 3 punch biopsy specimens: one from the leukoplakia, one 2.5mm from its marked borders, and one from healthy mucosa. Seventy-eight biopsy specimens were examined by an experienced pathologist, and 95% CI calculated to assess the amount of parakeratosis. Spearman's rank correlation was used to assess the association with mucosal inflammation. Ten areas of leukoplakia were surrounded by normal green autofluorescence, and 16 were consistent with loss of autofluorescence with a mean size of 66%, which exceeded the clinically visible size of the area of leukoplakia. We calculated that there was a strong association between these entities and their surrounding areas, with loss of autofluorescence for parakeratosis. Some leukoplakias showed clinically invisible extensions during histopathological examination and autofluorescence. The technique described enables clinicians to measure the extent of these lesions beyond their visible margins. We found no dysplasia, which emphasises that autofluorescence detects non-dysplastic lesions caused by mucosal inflammation and parakeratosis.

Chronological bias in randomized clinical trials arising from different types of unobserved time trends.

BACKGROUND: In clinical trials patients are commonly recruited sequentially over time incurring the risk of chronological bias due to (unobserved) time trends. To minimize the risk of chronological bias, a suitable randomization procedure should be chosen. OBJECTIVES: Considering different time trend scenarios, we aim at a detailed evaluation of the extent of chronological bias under permuted block randomization in order to provide recommendations regarding the choice of randomization at the design stage of a clinical trial and to assess the maximum extent of bias for a realized sequence in the analysis stage. METHODS: For the assessment of chronological bias we consider linear, logarithmic and stepwise trends illustrating typical changes during recruitment in clinical practice. Bias and variance of the treatment effect estimator as well as the empirical type I error rate when applying the t-test are investigated. Different sample sizes, block sizes and strengths of time trends are considered. RESULTS: Using large block sizes, a notable bias exists in the estimate of the treatment effect for specific sequences. This results in a heavily inflated type I error for realized worst-case sequences and an enlarged mean squared error of the treatment effect estimator. Decreasing the block size restricts these effects of time trends. Already applying permuted block randomization with two blocks instead of the random allocation rule achieves a good reduction of the mean squared error and of the inflated type I error. Averaged over all sequences, the type I error of the t-test is far below the nominal significance level due to an overestimated variance. CONCLUSIONS: Unobserved time trends can induce a strong bias in the treatment effect estimate and in the test decision. Therefore, already in the design stage of a clinical trial a suitable randomization procedure should be chosen. According to our results, small block sizes should be preferred, but also medium block sizes are sufficient to restrict chronological bias to an acceptable extent if other contrary aspects have to be considered (e.g. serious risk of selection bias). Regardless of the block size, a blocked ANOVA should be used because the t-test is far too conservative, even for weak time trends.

How to use information technology to improve medication safety.

The publication of a memorandum on improving medication safety by information technology in both the German journal GMS Medical Informatics, Biometry and Epidemiology (MIBE) and the journal Methods of Information in Medicine (MIM) gives reason to strengthen cooperation of MIBE and MIM and to report on more publications of MIBE here. The publications in focus deal with simulation-based optimization of emergency processes, handling of research data in publications, open access to research metadata, reliability of digital patient records in medical research, assessment methods for physical activity, using of insurance databases for epidemiological studies, certificates for epidemiological professionals, regression models, computer based training, and performance management in Swiss hospitals. Finally determining factors for scientific careers are discussed.

Hypoglycaemia and predisposing factors among clinical subgroups treated with intensive insulin therapy.

BACKGROUND: In previous studies, conflicting intensive insulin therapy (IIT) results have been observed, whereby IIT-related mortality seems to be lower in specific clinical subgroups. The aim of this study was to assess differences in glycaemic control, the risk of critical hypoglycaemia (≤ 2.2 mmol/l), the associated predisposing factors, and the in-hospital mortality in different clinical subgroups treated with IIT. METHODS: Prospective, observational study in a university-affiliated intensive care unit (ICU) conducted from 2004 to 2005. All patients (n = 1667) belonging to one of the six most common surgical intervention groups (cardiac, neuro, abdominal, vascular, orthopaedic, and spinal surgeries) and medical patients were included. IIT was performed with a target blood glucose level of 4.4-7.8 mmol/l. Different indices were analysed to evaluate glucose control and glycaemic variability. RESULTS: The rate of critical hypoglycaemia was significantly different within the different clinical subgroups and varied from 0.8% to 4.5%. Similar results were obtained for hyperglycaemia. Multivariable analyses for the predisposing factors of critical hypoglycaemia showed a heterogeneous distribution pattern among the different clinical subgroups. Similar results were obtained for the risk factors of in-hospital mortality. CONCLUSION: The risk of critical hypoglycaemia and the associated predisposing factors depended on the clinical subgroup involved. Critical hypoglycaemia is a potential threat for our patients, and the high risk of critical hypoglycaemia in some clinical subgroups appeared to reverse the benefits of IIT. As a result, it is crucial that the different subgroups involved in a study are defined to further interpret the potential benefits of IIT and the risk of critical hypoglycaemia.

[Increase in examinations for cataracts, glaucoma, diabetic retinopathy and age-related macular degeneration : Comparative cross-sectional study between 2010 and 1997 in ophthalmological practices]. / Zunahme der Untersuchungen wegen Katarakt, Glaukom, diabetischer Retinopathie und Makuladegeneration : Vergleichende Querschnittstudie der Jahre 2010 und 1997 in Augenarztpraxen.

BACKGROUND: The importance of the four most commonly occurring vision-threatening diseases, age-related macular degeneration (AMD), glaucoma, diabetic retinopathy and cataract in ophthalmological practices has changed due to demographic developments, medical progress and transference of inpatient treatment to the outpatient area of private practice. METHODS: In the fourth quarter year of 2010 a survey of 15,125 patients (approximately 10%) from 96 private ophthalmology practices (mean 149 patients per ophthalmologist, range 45-376) was carried out. The results for the four most commonly occurring vision-threatening diseases were compared with the result from a previous survey carried out for the fourth quarter year of 1997. RESULTS: Compared to 1997 there was an increase in the age-adjusted proportion of examinations in 2010 for cataracts by 29 %, for glaucoma by 21 %, for diabetic retinopathy by 39 % and for vitreoretinal diseases by 19 %. The number of AMD examinations in the age group over 70 years old showed a particularly high increase. CONCLUSIONS: The number of patients examined for the four most commonly occurring vision-threatening diseases increased from 1997 to 2010 not only in absolute numbers but also in relation to age. In the future financial and personnel resources must be made available for the early and guidelines-conform detection, diagnostics and therapy by ophthalmologists.

Reduction of central venous line-associated bloodstream infection rates by using a chlorhexidine-containing dressing.

PURPOSE: The reduction of central venous line (CVL)-associated bloodstream infections (CLABSIs) is generally advocated. However, despite implementing infection prevention recommendations, CLABSI rates remain high at some institutions. Therefore, a chlorhexidine-containing dressing should be assessed for its potential for infection reduction, adverse events (AEs) and practicability. METHODS: The number of CVLs, CVL days, CLABSIs and CLABSI rates with regard to the kind of dressing (standard vs. chlorhexidine-containing) were documented from November 2010 to may 2012 (1,298 patients with 12,220 CVL days) at two intensive care units (ICUs) and compared to historical controls. The practicability and safety of the chlorhexidine-containing dressing and reasons for not using this dressing were assessed. RESULTS: Forty CLABSIs occurred in 34 patients, resulting in a significantly lower overall CLABSI rate in patients with the chlorhexidine-containing dressing [1.51/1,000 CVL days; confidence interval (CI): 0.75-2.70] compared to patients with the standard dressing (5.87/1,000 CVL days; CI: 3.93-8.43; p < 0.0001). The CLABSI rate in historical controls receiving the standard dressing was 6.2/1,000 CVL days. The main reason for not using chlorhexidine-containing dressing was bleeding at the insertion site. AEs occurred in five patients and represented self-healing skin macerations (3 cases) and superficial skin necrosis (2 cases). CONCLUSIONS: In case of high CLABSI rates despite the implementation of standard recommendations, our findings suggest that a chlorhexidine-containing dressing safely decreases CLABSI rates.

[Evaluation of 12 pilot projects to improve outpatient palliative care]. / Evaluation von 12 Pilotprojekten zur Verbesserung der ambulanten Palliativversorgung.

BACKGROUND: With a priority programme the German Cancer Aid supported the development of quality-assured outpatient palliative care to cover the whole country. The 12 regional pilot projects funded with the aim to improve outpatient palliative care in different models and different frameworks were concurrently monitored and evaluated. METHODS: The supported projects, starting and ending individually, documented all patients who were cared for using HOPE (Hospice and palliative care evaluation) and MIDOS (Minimal documentation system for palliative patients). Total data were analyzed for 3239 patients decriptively. In addition to the quantitative data the experiences of the projects were recorded in a number of workshops (2008, 2009, 2010, and 2012). In particular, the experiences reported in the final meeting in July 2012 were considered for this article as well as the final reports for the German Cancer Aid. RESULTS: In the quantitative evaluation 85.6% of 3239 palliative care patients had a cancer diagnosis. In all model projects the goal of a network with close cooperation of primary providers, social support, and outpatient and inpatient specialist services has been achieved. For all projects, the initial financing of the German Cancer Aid was extremely important, because contracts with health insurance funds were negotiated slowly, and could then be built on the experiences with the projects. CONCLUSION: The participants of the project-completion meeting emphasized the need to carry out a market analysis before starting palliative care organizations considering the different regional structures and target groups of patients. Education, training and continuing education programs contribute significantly to the network. A reliably funded coordination center/case management across all institutions is extremely important.

More than four decades of medical informatics education for medical students in Germany. New recommendations published.

The publication of German competency-based learning objectives "Medical Informatics" for undergraduate medical education gives reason to report on more publications of the German journal GMS Medical Informatics, Biometry and Epidemiology ( MIBE ) in Methods. The publications in focus deal with support of medical education by health and biomedical informatics, hospital information systems and their relation to medical devices, transinstitutional health information systems and the need of national eHealth strategies, epidemiological research on predicting high consumption of resources, and with the interaction of epidemiologists and medical statisticians in examining mortality risks in diabetes, in genome wide association studies and in dealing with limits and thresholds. This report is the beginning of an annual series intending to support better international cooperation to achieve good information as a basis for good medicine and good healthcare.

Recommendations for reporting outcome results in abdominal wall repair: results of a Consensus meeting in Palermo, Italy, 28-30 June 2012.

BACKGROUND: The literature dealing with abdominal wall surgery is often flawed due to lack of adherence to accepted reporting standards and statistical methodology. MATERIALS AND METHODS: The EuraHS Working Group (European Registry of Abdominal Wall Hernias) organised a consensus meeting of surgical experts and researchers with an interest in abdominal wall surgery, including a statistician, the editors of the journal Hernia and scientists experienced in meta-analysis. Detailed discussions took place to identify the basic ground rules necessary to improve the quality of research reports related to abdominal wall reconstruction. RESULTS: A list of recommendations was formulated including more general issues on the scientific methodology and statistical approach. Standards and statements are available, each depending on the type of study that is being reported: the CONSORT statement for the Randomised Controlled Trials, the TREND statement for non randomised interventional studies, the STROBE statement for observational studies, the STARLITE statement for literature searches, the MOOSE statement for metaanalyses of observational studies and the PRISMA statement for systematic reviews and meta-analyses. A number of recommendations were made, including the use of previously published standard definitions and classifications relating to hernia variables and treatment; the use of the validated Clavien-Dindo classification to report complications in hernia surgery; the use of "time-to-event analysis" to report data on "freedom-of-recurrence" rather than the use of recurrence rates, because it is more sensitive and accounts for the patients that are lost to follow-up compared with other reporting methods. CONCLUSION: A set of recommendations for reporting outcome results of abdominal wall surgery was formulated as guidance for researchers. It is anticipated that the use of these recommendations will increase the quality and meaning of abdominal wall surgery research.

[Age, sex and diagnostic distribution of patients in ophthalmological medical practice in Germany]. / Die Patientenpopulation der augenärztlichen Praxen in Deutschland: Alter, Geschlecht und Diagnosen.

OBJECTIVE: The ophthalmological patient care in Germany has changed over the past decades due to demographic and diagnostic facility change and the shift from inpatient to outpatient care. METHOD: In the fourth quarter of 2010 a survey was conducted including almost 10 % of the patients of 96 ophthalmologists. The results for age, sex, main and secondary diagnosis and the main reason for the examination were examined and compared with those of surveys from 1966 and 1997. RESULTS: 15125 patients (median per doctor: 149, range: 45-376) were included in the survey. 58 % were women. The proportion of women was elevated in all decades compared to men, apart from the first age decade. The proportion of older patients (70 +) increased (1997: 25.3 %; 2010: 40.8 %) although the age distribution in Germany appears to be rather constant (1997: 11.9 %; 2010: 15.3 %). The proportion of examinations due to glaucoma, diabetes and vitreoretinal diseases increased by almost 60 % compared to 1997. CONCLUSION: Compared to the results of 1997, we observed a marked change from simple to differentiated cases in ophthalmological medical practice in Germany. The early diagnosis and therapy have to be guaranteed in the future taking into account the limited resources.

Can we place tension-free vaginal tape where it should be? The one-third rule.

OBJECTIVES: The tension-free vaginal tape (TVT) insertion technique generally does not take into account individual urethral length. In this study we investigated whether preoperative sonographic measurement of individual urethral length allows for reliable TVT positioning under the midurethra, which is a critical segment for the continence mechanism. METHODS: Urethral length was measured by preoperative introital ultrasonography in 102 consecutive female patients with stress urinary incontinence. TVT procedures were performed as recommended by the manufacturer. The suburethral incisions were initiated at one-third of the sonographically measured urethral length. TVT position and tape-urethra distance were followed up 6 months postoperatively. RESULTS: At 6-month examination of the 102 study participants, 93.1% were cured and 6.9% showed improved continence. TVTs were found in the target range of 50-70% of the urethral length in 88.2% of the cohort. Women with the TVT in the 50-70% urethral length range and a 3-5-mm tape-longitudinal smooth muscle distance had a greater likelihood of being cured without complications (P < 0.001). CONCLUSIONS: Preoperative sonographic measurement of urethral length, combined with the one-third rule, may aid in reliable midurethral TVT positioning.

Influence of aortic dimensions on the hemodynamic performance of small aortic valve prostheses: impact on patient/prosthesis mismatch.

BACKGROUND: Since Doppler echocardiography takes no account of pressure recovery, the true hemodynamic burden of aortic valve prostheses remains vague. The purpose of this study was to elucidate the methodological error of Doppler gradient estimation by means of a model demonstrating the different influence of aortic root diameters on net and Doppler gradients, respectively. This matters especially in small valves and the related patient/prosthesis mismatch calculation. METHODS: Two bileaflet small aortic valve prostheses (19 mm SJM Regent® and On-X® valve) were tested using a pulsatile circulatory mock loop simulator with two different aortic models: one with statistically normal diameters according to annular size, another one simulating an aortic aneurysm of 50 mm. Doppler and simultaneously recorded net gradients as well as systolic energy losses were obtained for different hemodynamic conditions. RESULTS: In all measurements a significant amount of pressure recovery was observed. In cases of aortic aneurysm systolic energy loss increased significantly for each cardiac output at each heart rate ( P < 0.0028), reflected by a significant ( P < 0.0001) increase in net gradients. The corresponding Doppler gradients were unchanged. This indicates significantly less pressure recovery ( P < 0.0001) in the aneurysmatic aorta. CONCLUSIONS: Geometry of the ascending aorta considerably alters aortic valve hemodynamic parameters. The hemodynamic function of small aortic valve prostheses, especially with corresponding normal outflow dimensions, is much better than expected from Doppler gradients. Thus, calculation of a patient/prosthesis mismatch can be misleading.

The use of the Foley Airway Stylet Tool® to guide tracheal intubations through an intubating laryngeal mask airway.

BACKGROUND: Blind insertion of endotracheal tubes through the intubating laryngeal mask airway (ILMA) is unsuccessful in almost 50% of cases on the first attempt, with an overall success rate of approximately 90%. We used a portable fiber optic device (Foley Airway Stylet Tool® FAST) to detect the reasons for failed intubations and tested its use in facilitating endotracheal tube placement. METHODS: Thirty patients without anticipated intubation difficulties participated in the study. The fiber optic device was fastened with its tip at the end of the endotracheal tube, and both instruments were advanced through the previously inserted ILMA past the lifting bar. The view was scored in the following manner: I, full view of laryngeal inlet; II, partial vocal cords, arytenoids, epiglottis; III, epiglottis; IV, no laryngeal structures identifiable. The ILMA was adjusted for the best obtainable view, which was scored, and the endotracheal tube was inserted. RESULTS: The initial laryngeal view was I in four patients, II in eighteen patients, III in one patient and IV in seven patients. The best view after corrective maneuvers was I in twenty-seven patients, II in two patients and IV in one patient. First attempt tracheal intubations were successful in twenty-seven (90%) patients; two patients required a second attempt. CONCLUSION: A grade II view or worse indicated misalignment of the ILMA with the glottis. An endotracheal tube inserted blindly through the misaligned ILMA will impinge on and potentially damage laryngeal structures. The use of a portable fiber optic device can help reduce the failure rate of endotracheal intubations by utilizing ILMA in emergent situations.

Hypercholesterolemia and its association with enhanced stem cell mobilization and harvest after high-dose cyclophosphamide+G-CSF.

High-dose chemotherapy with autologous peripheral blood SCT is a common treatment option in several hematological and non-hematological malignancies. So far, prediction of successful stem cell mobilization and harvest is limited. Just recently, hypercholesterolemia was shown to increase mobilization of hematopoietic progenitor cells into the peripheral circulation in mice. On the basis of these results, we performed a retrospective multivariate analysis incorporating a variety of clinical parameters in 83 patients following high-dose cyclophosphamide+G-CSF treatment. Interestingly, we found a significant positive correlation between stem cell mobilization and harvest for plasma cholesterol and lactate dehydrogenase (LDH) only. Patients with hypercholesterolemia showed a substantially higher median peripheral blood CD34(+)-peak (126 vs 47/µL, P=0.003), higher median number of harvested CD34(+)-cells/kg (9.6 vs 7.4 × 10(6)/kg, P<0.001) and a sufficient number for at least one SCT in a remarkably higher proportion (84.9 vs 52.9%, P=0.003) compared with patients with normal cholesterol levels.

Intermediate filament dynamics and breast cancer: aberrant promoter methylation of the Synemin gene is associated with early tumor relapse.

Synemin (SYNM) is a type IV intermediate filament that has recently been shown to interact with the LIM domain protein zyxin, thereby possibly modulating cell adhesion and cell motility. Owing to this multiplicity of potential functions relevant to cancer development, we initiated a study to decipher SYNM expression and regulation in benign human breast tissue and breast cancer. Dot blot array analysis showed significant SYNM mRNA downregulation in 86% (n=100, P<0.001) of breast cancers compared with their normal tissue counterparts, a result that was confirmed by real-time PCR analysis (n=36, P<0.0001). Immunohistochemistry analysis showed abundant SYNM protein expression in healthy myoepithelial breast cells, whereas SYNM expression loss was evident in 57% (n=37, P<0.001) of breast cancer specimens. Next, we analyzed methylation of the SYNM promoter to clarify whether the SYNM gene can be silenced by epigenetic means. Indeed, methylation-specific PCR analysis showed tumor-specific SYNM promoter methylation in 27% (n=195) of breast cancers. As expected, SYNM promoter methylation was tightly associated (P<0.0001) with SYNM expression loss. In-depth analysis of the SYNM promoter by pyrosequencing showed extensive CpG methylation of DNA elements supposed to regulate gene transcription. Demethylating treatment of SYNM methylated breast cancer cell lines with 5-aza-2-deoxycytidine clearly reestablished the SYNM expression. Statistical analysis of the patient cohort showed a close association between SYNM promoter methylation and unfavorable recurrence-free survival (hazard ratio=2.941, P=0.0282). Furthermore, SYNM methylation positively correlated with lymph node metastases (P=0.0177) and advanced tumor grade (P=0.0275), suggesting that SYNM methylation is associated with aggressive forms of breast cancer. This is the first study on the epigenetic regulation of the SYNM gene in a cancer entity. We provide first hints that SYNM could represent a novel putative breast tumor suppressor gene that is prone to epigenetic silencing. SYNM promoter methylation may become a useful predictive biomarker to stratify breast cancer patients' risk for tumor relapse.

Myoendothelial coupling in the mesenteric arterial bed; segmental differences and interplay between nitric oxide and endothelin-1.

BACKGROUND AND PURPOSE: We tested the hypothesis that activated arterial smooth muscle (ASM) stimulates endothelial vasomotor influences via gap junctions and that the significance of this myoendothelial coupling increases with decreasing arterial diameter. EXPERIMENTAL APPROACH: From WKY rats, first-, second-, third- and fourth-order branches of the superior mesenteric artery (MA1, MA2, MA3 and MA4 respectively) were isolated and mounted in wire-myographs to record vasomotor responses to 0.16-20 micromol x L(-1) phenylephrine. KEY RESULTS: Removal of endothelium increased the sensitivity (pEC(50)) to phenylephrine in all arteries. The nitric oxide (NO) synthase inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME) (100 micromol x L(-1)) did not modify pEC(50) to phenylephrine in all denuded arteries, and increased it in intact MA1, MA2 and MA3 to the same extent as denudation. However, in intact MA4, the effect of L-NAME was significantly larger (DeltapEC(50) 0.57 +/- 0.02) than the effect of endothelium removal (DeltapEC(50) 0.20 +/- 0.06). This endothelium-dependent effect of L-NAME in MA4 was inhibited by (i) steroidal and peptidergic uncouplers of gap junctions; (ii) a low concentration of the NO donor sodium nitroprusside; and (iii) by the endothelin-receptor antagonist bosentan. It was also observed during contractions induced by (i) calcium channel activation (BayK 8644, 0.001-1 micromol x L(-1)); (ii) depolarization (10-40 mmol x L(-1) K(+)); and (iii) sympathetic nerve stimulation (0.25-32 Hz). CONCLUSIONS AND IMPLICATIONS: These pharmacological observations indicated feedback control by endothelium of ASM reactivity involving gap junctions and a balance between endothelium-derived NO and endothelin-1. This myoendothelial coupling was most prominent in distal resistance arteries.

[Anaylsis of the surgeon factor in the treatment results of rhegmatogenous retinal detachment in the "scleral buckling versus primary vitrectomy in rhegmatogenous retinal detachment study"]. / Einfluss des Operateurs auf die Operationsergebnisse bei rhegmatogener Ablatio retinae im Rahmen der "Scleral Buckling versus Primary Vitrectomy in Rhegmatogenous Retinal Detachment Study".

BACKGROUND: The effect of the surgeon on the outcome of surgical treatment for rhegmatogenous retinal detachment (RRD) has previously been analysed in a few studies only. In the prospective multicentre SPR study, scleral buckling (SBS) and primary vitrectomy (PV) were compared in RRD with medium complexity in a randomised fashion. In this study, we examined the surgeon factor on the outcome of RRD surgery within the SPR study. MATERIAL AND METHODS: An analysis of the surgeon as a factor on the functional outcome (logMAR visual acuity), primary anatomic success (retinal reattachment central to the aequator without any additional retina-affecting surgery including laser, cryo and macular pucker surgery) and final anatomic success (retinal reattachment one year postoperatively) was carried out. RESULTS: Overall, 416 phakic patients (209 SBS, 207 PV) and 265 pseudophakic patients (133 SB, 132 PV) were recruited by 45 surgeons in 25 centres. In the phakic group, the mean functional outcome of individual surgeons was between 0.2 and 0.74 (mean, 0.41, SD 0.41). This difference reached statistical significance (p = 0.0398). In the pseudophakic subgroup, the mean functional outcome was between 0.09 and 0.64 (mean, 0.42, SD 0.49) without reaching a statistical significance (p = 0.0715). Primary success per surgeon varied between 41.67 % and 90.00 % (mean, 63.16 %) in the phakic subgroup and 33.33- 80.95 % (mean, 61.75 %) in the pseudophakic subgroup. Final anatomic success was achieved in 92.86 - 100.00 % (mean, 97.96 %) in the phakic subgroup and 80.00 - 100.00 % (mean, 95.44 %) in the pseudophakic subgroup. There was no statistically significant correlation between surgeon and anatomic outcomes. CONCLUSION: In the phakic subgroup, a statistically significant correlation between surgeon and functional success could be demonstrated for RRD with medium complexity. This correlation was not interrelated to the surgical method. Functional outcome in pseudophakic patients and anatomic outcomes in both subgroups of phakic and pseudophakic patients showed no statistically significant correlation between surgeon and anatomic success.