Relaxation dynamics in excited helium nanodroplets probed with high resolution, time-resolved photoelectron spectroscopy.

Superfluid helium nanodroplets are often considered as transparent and chemically inert nanometer-sized cryo-matrices for high-resolution or time-resolved spectroscopy of embedded molecules and clusters. On the other hand, when the helium nanodroplets are resonantly excited with XUV radiation, a multitude of ultrafast processes are initiated, such as relaxation into metastable states, formation of nanoscopic bubbles or excimers, and autoionization channels generating low-energy free electrons. Here, we discuss the full spectrum of ultrafast relaxation processes observed when helium nanodroplets are electronically excited. In particular, we perform an in-depth study of the relaxation dynamics occurring in the lowest 1s2s and 1s2p droplet bands using high resolution, time-resolved photoelectron spectroscopy. The simplified excitation scheme and improved resolution allow us to identify the relaxation into metastable triplet and excimer states even when exciting below the droplets' autoionization threshold, unobserved in previous studies.

Single-shot dispersion sampling for optical pulse reconstruction.

We present a novel approach to single-shot characterization of the spectral phase of broadband laser pulses. Our method is inexpensive, insensitive to alignment and combines the simplicity and robustness of the dispersion scan technique, that does not require spatio-temporal pulse overlap, with the advantages of single-shot pulse characterization methods such as single-shot frequency-resolved optical gating at a real-time reconstruction rate of several Hz.

Time-resolved nuclear dynamics in bound and dissociating acetylene.

We have investigated nuclear dynamics in bound and dissociating acetylene molecular ions in a time-resolved reaction microscopy experiment with a pair of few-cycle pulses. Vibrating bound acetylene cations or dissociating dications are produced by the first pulse. The second pulse probes the nuclear dynamics by ionization to higher charge states and Coulomb explosion of the molecule. For the bound cations, we observed vibrations in acetylene (HCCH) and its isomer vinylidene (CCHH) along the CC-bond with a periodicity of around 26 fs. For dissociating dication molecules, a clear indication of enhanced ionization is found to occur along the CH- and CC-bonds after 10 fs to 40 fs. The time-dependent ionization processes are simulated using semi-classical on-the-fly dynamics revealing the underling mechanisms.

Allogeneic Blood Product Usage in Coronary Artery Bypass Grafting (CABG) with minimalized Extracorporeal Circulation System (MECC) Versus Standard On-Pump Coronary Artery Bypass Grafting.

AIM: Intraoperative allogeneic blood product transfusion (ABPT) in cardiac surgery is associated with worse overall outcome, including mortality. The objective of this study was to evaluate the ABPTs in minimalized extracorporeal cardiopulmonary (MECC(TM)) compared with standard open system on-pump coronary revascularization. METHODS: Data of 156 patients undergoing myocardial revascularization between September 2008 and September 2010 were reviewed. 83 patients were operated by the MECC technique and 73 were treated by standard extracorporeal circulation (sECC). ABPT and overall early postoperative complications were analyzed. RESULTS: Operative mortality and morbidity were similar in both groups. ABPT in the MECC group was significantly lower than in the sECC group both intraoperatively (7.2 vs. 60.3% of patients p<0.001) and during the first five postoperative days (19.3 vs. 57.5%; p<0.001). "Skin to skin"- (214 ± 45 vs. 232 ± 45 min; p=0.012), cardiopulmonary bypass (CPB) - (82 ± 25 vs. 95 ± 26 min; p=0.014), and X-clamp- times (50 ± 16 vs. 56 ± 17 min; p=0.024) were significantly lower in the MECC group than in the sECC group. Length of ICU (intensive care unit) - and hospital stay were also significantly lower in the MECC group vs. the sECC group (26.7 ± 20.2 vs. 54.5 ± 68.9 h; p<0.001, and 12.0 ± 4.1 vs. 14.5 ± 4.6 days; p<0.001). CONCLUSION: Application of MECC as on-pump coronary artery bypass graft (CABG) results in significantly lower ABPT as well as shorter ICU and in-hospital stay. In order to achieve these benefits of MECC autologous retrograde priming, Bispectral index (BIS) monitoring, intraoperative cell salvage, meticulous hemostasis and strict peri- and postoperative volume management are crucial.

[S3 guidelines on volume therapy: Comments on publication 2014]. / S3-Leitlinie Volumentherapie : Kommentar zur Veröffentlichung 2014.

Intravascular volume therapy represents one of the pillars of medical actions during inpatient treatment and is dealt with in the S3 guidelines on "intravascular volume therapy in adults". The target group of the guidelines are physicians who must carry out intravascular volume therapy as a component of patient treatment. This article critically reviews and summarizes the essential recommendations.

[Application fields of intraoperative transesophageal 3D echocardiography]. / Anwendungsgebiete der intraoperativen transösophagealen 3D-Echokardiographie.

Intraoperative transesophageal echocardiography (TEE) is an established diagnostic tool and has to be regarded as the standard of care for intraoperative monitoring and cardiac surgical decision-making. Furthermore, intraoperative TEE is also used for monitoring and assessment of hemodynamic changes and the detection of previously unknown pathologies. In the past few years 3D-TEE has extended the spectrum of 2D-TEE by allowing pathomorphological features to be more easily and intuitively linked to the anatomy of the heart and the great vessels. Thus, a comprehensive 2D-TEE examination is favorably complemented by focused 3D-TEE. Especially during mitral valve surgery, 3D-TEE has proven its superiority in the diagnosis of the underlying pathology as demonstrated by a large number of studies in this field. This review presents the available data about the role of intraoperative 3D-TEE echocardiography and introduces practical fields of application.

Crucial role of Plexin C1 for pulmonary inflammation and survival during lung injury.

Acute pulmonary inflammation during lung injury is initiated by the migration of neutrophils into the alveolar space. The severity of these inflammatory changes within the pulmonary tissue determines the severity of lung injury and ultimately patient outcome. Recent work has demonstrated that the guidance protein Semaphorin 7A propagates the infiltration of neutrophils into an hypoxic tissue site, yet the role of its target receptor Plexin C1 (PLXNC1) during lung injury is to date unknown. We demonstrate here that PLXNC1(+) neutrophils are present within the alveolar space and that PLXNC1 is induced in vitro and in vivo during lung injury. In a model of high-pressure ventilation PLXNC1(-/-) animals show decreased signs of alveolar inflammation and improved survival compared with wild-type controls. Studies employing chimeric animals identified the hematopoietic expression of PLXNC1 to be of crucial importance for the observed results. Functional inhibition of PLXNC1 resulted in improved survival and ameliorated the signs of inflammation within the lung. Furthermore, the injection of a peptide binding to PLXNC1 resulted in improved survival and attenuated pulmonary inflammation. As such we demonstrate here, that previously unknown PLXNC1 holds significant importance for degree of pulmonary inflammation and determines outcome during experimental lung injury.

[A new working shift model for anesthesiologists: an analysis 3 years after implementation]. / Neues Dienstzeitenmodell für Ärzte in der Anästhesie : Eine Analyse 3 Jahre nach Implementierung.

OBJECTIVE: The aim of this study was to assess the efficacy, appropriateness and cost-effectiveness of a new working shift model for anesthesiologists complying with the European working time directive (EWTD) at the University Hospital of Tübingen (UKT), Germany 3 years after implementation BACKGROUND: Applying the standards of the EWTD is challenging for university hospitals as doctors must comply with the challenge of combining patient care, research and teaching. So far there have been no data available for German university hospitals on how these requirements can be met. As the department of anesthesiology is also a service-providing department it is essential not to increase staffing costs with a new shift model. METHODS: In 2007 a new working shift model for the department of anesthesiology was designed and introduced in 2008. Shift planning and documentation of working hours were implemented electronically. The calculated number of doctors to run this model was 87.6 full time equivalents (FTE). For 2009 and 2010 the compliance with the EWTD parameters was checked for 1) average weekly working time limit (AWWTL) and 2) compliance to the maximum daily working time limit of 10 h (10 h DWTL). Furthermore, staffing costs for doctors in 2010 were compared to 2007. To check for the time spent in patient care the period of anesthetic attendance (PAA) was chosen, i.e. the total time of patient contact by anesthesiology staff. Data were analyzed descriptively for AWWTL and for 10 h DWTL. FTE, staff costs and PAA were evaluated by one-way ANOVA. RESULTS: The new shift model allowed 84.4 % of all doctors to comply with the individual AWWT limits of 54 h and 48 h in 2009 (81/96) and 76.0 % in 2010 (79/104). In 2009 61.5 % of anesthesiologists voted for opt-out (59/96) and 53.8 % did so in 2010 (56/104). The 10 h DWTL was respected by 84.0 % in 2009 and by 85.9 % in 2010. The mean number of anesthesiologists rose significantly from 78.4 FTE in 2007 to 82.5 FTE in 2009 and 84.6 FTE in 2010 (p < 0.001 for 2010 vs. 2007, p = 0.004 for 2009 vs. 2007 and was not significant for 2010 vs. 2009). Staff costs per FTE increased from 7,524.79 /month to 7,800.66 /month and 7,966.11 /month in 2007, 2009 and 2010, respectively with the differences being non-significant. The PAA increased significantly from a mean of 6,124 h/month in 2007 to 6,581 h/month in 2009 and 6,872 h/month in 2010 (p < 0.001 for 2010 vs. 2007, whereas 2009 vs. 2007 and 2010 vs. 2009 were not significant). Thus, labour costs increased from 96.59 /h PAA in 2007 to 98.53 /h in both 2009 and 2010, the differences being not significant. CONCLUSIONS: The newly designed shift model allowed a fair compliance with the EWTD in respect to AWTL and 10 h DWTL, although the calculated number of doctors to run the shift model could not be met in 2009 and 2010. Violations of the 10 h DWT limits were stable in 2009 and 2010; however the number of doctors exceeding the AWWT limits appeared to increase. The compliance with opt-out decreased from 2009 to 2010 and a high proportion of AWWTL violations resulted from the group of non-opt-out voters. The staff costs per hour PAA after implementation of the new shift model did not differ significantly from the year before although staffing costs increased by 7.2 % between 2007 and 2010. Costs increased by 162,454 /year for all PAA hours in 2010. Further evaluation of staff satisfaction with the new shift models is needed and already under way.

[Scope and limitations of the median nerve mouse model in research on peripheral nerve regeneration]. / Möglichkeiten und Grenzen des N. medianus Maus Modells bei der Erforschung der peripheren Nervenregeneration.

INTRODUCTION: Peripheral nerve regeneration is usually studied in rat animal models (N. medianus or N. ischiadicus). In this article, we further evaluate the mouse median nerve model with its advantages and possible pitfalls. MATERIALS AND METHODS: 24 mice (C57BL/6) were operated. The median nerve was exposed in the left axilla. After transection, immediate microsurgical repair followed using 11/0 sutures. In the contralateral axilla, 1 cm of median nerve was resected. After the operation, functional regeneration of the median nerve was assessed using the grasping test. Histological analysis was performed after staining with toluidine blue. RESULTS: All animals survived the procedure. Grip strength increased starting at day 10 and reached its maximum at day 35. Myelinated fibres in the regenerated nerves showed a smaller diameter and a thinner myelin sheath and the typical microfasciculation of regenerated nerve fibres in comparison to the uninjured nerve. CONCLUSION: The mouse median nerve model is technically demanding but opens a wide field of possible research options using genetically modified mice.

[Intraoperative echocardiography: impact on surgical decision-making]. / Intraoperative Echokardiographie : Einfluss auf das chirurgische Management.

Since the introduction of intraoperative echocardiography into clinical practice in the 1970's its use and utility in the perioperative period has become increasingly more evident. Especially in patients undergoing cardiac surgical procedures intraoperative echocardiography has gained great diagnostic importance. Intraoperative transesophageal echocardiography (TEE) and epiaortic ultrasound are two important and complementing diagnostic modalities in this patient population. The clinical information obtained with intraoperative TEE in certain cases might have a direct impact on surgical decision-making and therefore may positively influence patient outcome. In patients undergoing non-cardiac surgical procedures, TEE can be a valuable tool in high-risk patients, in patients experiencing hemodynamic instability or in those suffering intraoperative cardiac arrest. Intraoperative TEE might allow a primary diagnosis of the underlying etiology and facilitate the institution of further therapeutic interventions. In addition TEE can be performed during ongoing cardiopulmonary resuscitation and does not interfere with patient management. This review introduces the clinician to the current evidence of the impact of intraoperative echocardiography on intraoperative surgical decisions during surgical procedures. It helps the clinician to identify indications and realize the potential applications of intraoperative echocardiography.

[Perioperative echocardiography: basic principles]. / Perioperative Echokardiographie: Technische Grundlagen für den Kliniker.

Over the past decades, echocardiography has undergone a continuous evolution in technology that has promoted its clinical application and acceptance throughout perioperative medicine. These technological advances include improvements in transducer development that permit superior imaging quality and a wider selection of probes for epicardial, epiaortic, and surface echocardiography which can also be used in conjunction with multiplane transesophageal echocardiography. Moreover, the addition of Doppler technology and digital acquisition has secured the role of echocardiography as a valuable and relatively noninvasive diagnostic tool for the assessment of cardiovascular disease and hemodynamic monitoring throughout the perioperative period. Therefore, it has become increasingly important for perioperative physicians to understand the basic principles and underlying fundamental concepts pertaining to the technology and physics of echocardiography, as well as its inherent limitations. The current review outlines the modes and applications of different echocardiographic techniques used in perioperative echocardiography including M-mode, two-dimensional echocardiography, and Doppler assessment of blood flow. In addition, the limitations of these techniques and typical artifacts associated with the perioperative use of echocardiography are described.

[Preoperative evaluation and perioperative management of patients with increased cardiovascular risk]. / Präoperative Evaluation und perioperatives Vorgehen bei kardialen Risikopatienten.

Due to the increasing age in western countries, combined with high rates of major surgical interventions in high-risk patients, perioperative reduction of cardiovascular complications becomes increasingly more important for perioperative physicians. After identifying patients with increased perioperative risk, specific interventions need to be considered to reduce their risk for cardiovascular complications, either by perioperative medical therapy or specific treatment options (e.g. coronary intervention). Several trials have demonstrated an effect of perioperative beta-blocker-therapy in reducing cardiovascular complications among high-risk patients. Additionally, several monitoring techniques are effective in detecting cardiovascular complications. Nevertheless, it remains unclear whether they are associated with a measurable improvement of outcome. Based on the ACC/AHA-guidelines, the present review describes a stepwise approach to surgical patients to identify perioperative risks, based on specific patient related risk factors, the kind of surgery and on the specific setting (emergency versus elective surgery). In addition, strategies to reduce perioperative cardiovascular complications are discussed.

[Epicardial echocardiography intraoperative diagnostic utility to assess valve function]. / Epikardiale EchokardiographieIntraoperative Beurteilung der Klappenfunktion.

Epicardial echocardiography has been available since the early 1970s as an intraoperative diagnostic modality to assess ventricular and valvular function. With this technique, an ultrasonic transducer is placed directly on the epicardial surface of the heart, following sternotomy and pericardiotomy. Under the guidance of the cardiac anesthesiologist, the surgeon places the transducer so that the desired views of cardiac structures and great vessels can be obtained. The anesthesiologist performs the acquisition, analysis and interpretation of the echocardiographic images. Despite the feasibility of epicardial echocardiography, transesophageal echocardiography (TEE) has emerged over the last two decades as the main form of intraoperative echocardiography. Although TEE allows continuous monitoring of cardiac and valvular function without interruption of the surgical procedure, placement of a TEE probe may be difficult or contraindicated in some patients. In such cases, epicardial echocardiography may be the optimal ultrasonographic imaging modality to assess ventricular and valvular function during cardiac surgery. We describe the use of epicardial echocardiography for intraoperative assessment of valvular function in two patients where TEE was either contraindicated or probe placement could not be performed safely. The first patient underwent surgical repair of the mitral valve for severe mitral regurgitation. After weaning the patient from cardiopulmonary bypass (CPB), epicardial echocardiography was used to confirm successful reconstruction of the valve and to exclude residual mitral regurgitation. The second patient was scheduled for coronary artery bypass grafting (CABG). Prior to the initiation of CPB, the presence of moderate aortic stenosis was confirmed using Doppler echocardiography via an epicardial approach.

Intelligence and physical features of children of women with epilepsy.

The teratogenicity of maternal epilepsy has been attributed to several factors, including the antiepileptic drugs taken to prevent seizures during pregnancy, the occurrence of seizures during pregnancy, and the factors in the mother that caused her to have epilepsy. We have addressed the hypothesis that the children of women who have a history of epilepsy (seizure history), but who took no antiepileptic drugs (AED) and had no tonic-clonic seizures in pregnancy, have an increased risk of malformations and diminished intelligence. The frequency of cognitive dysfunction was determined in 57 seizure history and 57 matched control children aged 6-l6 years. The masked evaluation of the children included a physical and neurologic examination and testing with the Wechsler Intelligence Scale for Children-Revised (WISC-R) and a systematic physical examination for the features of the fetal AED syndrome. The evaluation of both parents of each child included a test of reasoning (Ravens Progressive Matrix) and a physical examination. There were no differences between the two groups of children in either IQ scores or physical features; none of the seizure history children was judged to have the "anticonvulsant face" or digit hypoplasia. This study had 80% power to rule out a difference of seven or more IQ points between the two groups, based on a two-sided test at a 5% level of significance. Our confidence in concluding that there was no difference between seizure history and control infants was strengthened by the fact that no statistically significant differences were observed with respect to multiple outcomes, including eight related measures of intelligence. Thirty (53%) of the seizure history mothers resumed taking AED after the birth of the child we evaluated. Additional studies are needed to address the teratogenicity of the antiepileptic drugs as monotherapy.

Depletion of cutaneous peptidergic innervation in HIV-associated xerosis.

Severe xerosis occurs in approximately 20% of human immunodeficiency virus seropositive patients. Changes in cutaneous innervation have been found in various inflammatory skin diseases and in xerotic skin in familial amyloid. We have therefore carried out a quantitative examination of the cutaneous peptidergic innervation in human immunodeficiency virus-associated xerosis. Immunohistochemistry and image analysis quantitation were used to compare total cutaneous innervation (protein gene product 9.5), calcitonin gene-related peptide, substance P, and vasoactive intestinal peptide peptidergic fibers, at two sites in the skin of human immunodeficiency virus-associated xerosis patients (upper arm, n = 12; upper leg, n = 11) and site-matched seronegative controls (upper arm, n = 10; upper leg, n = 10). Measurement of lengths of fibers of each type was carried out for each subject in the epidermis and papillary dermis, and around the sweat glands. Immunostained mast cells in these areas were counted. Epidermal integrity and maturation were assessed by immunostaining for involucrin. There were significant (Mann-Whitney U test; p < 0.02) decreases in total lengths of protein gene product 9.5 fibers in both epidermis/papillary dermis and sweat gland fields; of calcitonin gene-related peptide innervation in the epidermis/papillary dermis; and of substance P innervation of the sweat glands. There were no differences in the distribution of mast cells, or in the epidermal expression of involucrin. Depletion of the calcitonin gene-related peptide innervation may affect the nutrient blood supply of the upper dermis, and the integrity and function of basal epidermis and Langerhans cells. Diminished substance P innervation of the sweat glands may affect their secretory activity. Both of these changes may be implicated in the development of xerosis.

Depression and neuropsychological performance in asymptomatic HIV infection.

OBJECTIVE: The authors examined the effect of depression on neuropsychological performance in HIV-infected men. Previous studies have suggested that depression may account for the neuropsychological abnormalities observed in some patients with HIV infection, but few studies have specifically examined this question. METHOD: An extensive neuropsychological test battery was administered to 121 HIV-seropositive asymptomatic men and 42 HIV-seronegative comparison subjects. The seropositive subjects were grouped into depressed and non-depressed groups on the basis of scores on the Beck Depression Inventory, Hamilton Rating Scale for Depression, and Structured Clinical Interview for DSM-III-R. RESULTS: Statistical comparisons revealed very few measures on which the depressed seropositive subjects scored significantly worse than either of the nondepressed comparison groups. The nondepressed seropositive group differed consistently from the seronegative comparison subjects on measures of verbal memory and dexterity. CONCLUSIONS: These data indicate that the subtle neuropsychological abnormalities observed in some asymptomatic HIV-seropositive subjects cannot be attributed to depression. These data also indicate the advantages of a multifaceted approach to assessment of depression.

Psychopathology in human immunodeficiency virus infection: lifetime and current assessment.

The present study determined lifetime and current psychiatric functioning in a sample of homosexual or bisexual men at various stages of human immunodeficiency virus (HIV) infection in order to address several questions regarding the relationship between psychopathology and HIV infection. HIV+ asymptomatic or symptomatic and HIV- homosexual or bisexual men completed self-report measures of psychological and health functioning and participated in structured diagnostic interviews. Additional information regarding HIV-related life events and their potential relationship to onset of disorder and family history of psychiatric disorder were obtained. A high lifetime prevalence of affective and substance use disorder was found, with almost one half of the sample meeting criteria for both disorders. Lifetime affective disorder diagnosis was associated with a positive family history of affective disorder. HIV-related events were most closely associated with onset or recurrence of affective disorder compared with other disorders. Low current rates of psychiatric disorder and levels of emotional distress were found, with no differences in degree of psychiatric adjustment across stage of infection. We conclude that the lifetime prevalence of certain categories of psychiatric disorder is high in both HIV+ and HIV- homosexual samples. Increased rates of psychiatric disorders do not appear to be a consequence of HIV infection. However, episodes of illness, particularly affective disorder, may develop following an HIV-related event such as confirmation of infection. Although symptomatic subjects have more somatic difficulties, there appears to be no relationship between stage of illness and level of emotional distress.

Neuropsychological performance in symptomatic and asymptomatic HIV infection.

OBJECTIVE: To examine cognitive function in patients at various stages of HIV infection, and to determine the nature and severity associated with stage of illness. DESIGN: Subjects were administered an extensive battery of neuropsychological tests. SUBJECTS: Two hundred and thirty-three HIV-1-infected homosexual/bisexual men and 77 HIV-negative control subjects who had been screened for previous neurological illness. All subjects were volunteers in a longitudinal study of neurobehavioral complications of HIV infection. RESULTS: Patients with symptomatic infection differed from controls on a large number of measures, and asymptomatic patients had a more circumscribed pattern of deficit. On a summary measure of cognitive impairment, there was a twofold increase in the prevalence of impairment in asymptomatic patients relative to controls, and a fourfold increase in symptomatic patients. Memory and dexterity problems appear to be early features of neurobehavioral dysfunction, and frontal lobe deficits were found in patients with symptomatic infection. CONCLUSION: These data indicate that there is a steady increase in the prevalence of neurobehavioral abnormalities associated with stage of infection. The pattern of abnormality also varies with disease stage.

Drug and alcohol use and neuropsychological performance in asymptomatic HIV infection.

The effect of drug and alcohol abuse on neuropsychological performance was examined in 132 human immunodeficiency virus-seropositive gay or bisexual men. Syndromal (diagnostic) criteria of alcohol/drug abuse based on DSM-III-R were used, and quantitative estimates of alcohol consumption were obtained. Very few differences appeared between substance abuse subgroups formed on the basis of recency or severity of drug use. There were some correlations with the quantitative estimate of alcohol use, but not on the measures previously found to differentiate seronegative and asymptomatic seropositive gay men. These data indicate that alcohol use does affect neuropsychological performance but does not account for the differences observed in studies of seronegative and seropositive subjects.