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Lectins are naturally occurring molecules which bind to specific carbohydrates of glycoconjugates. The binding specificity of lectins can therefore be used to specifically elucidate the glycosylation pattern in various tissues. While lectin histochemistry is usually carried out manually on single slides, a fully automated immunostaining system offers an easy, standardized, and high throughput system. In this study lectin histochemistry was implemented and optimized on a fully automated immunostaining system to investigate glycosylation patterns in the murine respiratory tract and the primary olfactory pathway. We tested 22 commercially available biotinylated lectins for their labelling-profiles to specifically identify morphologic structures. The results showed that lectin staining profiles using the implemented protocol on the automated system were constant and suitable for high throughput morphological studies. Further, the morphological evaluation of the stained slides revealed a complete characterization of the murine respiratory tract and primary olfactory pathway including the lectin binding profiles for the olfactory bulb, the vomeronasal organ and the nasal-associated lymphoid tissue.

The Best Value Approach (BVA) has been used as a method to procure and manage services. As the BVA is further proliferated, there are applications of the BVA which deviate from the standard approach which are labeled as hybrid processes. This research focuses on better understanding BVA hybrid projects and the implications that may arise with such deviations. Using case study research, the BVA was used to procure services for the construction of ships. The research findings show the impact of hybrid applications of the BVA including (1) the selection of suppliers based on decision making instead of expertise (2) attempts to share and transfer risk, (3) incomplete clarification phase planning by expert suppliers, and (4) incomplete use of the Weekly Risk Report and Director’s report to track project deviation. The resulting hybrid application was found to have increased costs, increased decision making, and created a non-transparent environment. Suggestions have been made to improve upon these areas by applying the BVA structure including a selection process to identify expertise and a project management process which utilizes the supplier’s expertise to create a structure of transparency through performance metrics.

By means of harmonic imaging, it is possible to display brain perfusion qualitatively using ultrasound (US) contrast agent (UCA) bolus injection. With UCA continuous infusion reaching a steady state, mean microbubble velocity can be measured, analyzing the reappearance rate after microbubble destruction by US (refill kinetics). We performed an animal pilot study to investigate this new method for the assessment of brain perfusion. Using harmonic grey-scale imaging, five sedated male beagle dogs were investigated through the intact skull with increasing pulsing intervals (250 to 8000 ms) and three UCA infusion rates (0.5, 1.0 and 1.5 mL/min of Optison™). Cerebral blood flow was increased by acetazolamide (30 mg/kg BW). Intensity vs. pulsing interval curves were analyzed using an exponential curve fit [ I(t) = A (1- e −βt ) ] and parameters of the curve were compared. We found that increasing the pulsing interval above 4000 ms led to no further increase of echo enhancement for infusion rates. Mean β values were not influenced by infusion rate ( p = 0.25 and p = 0.55). Mean F values increased nonsignificantly with rising infusion rate ( p = 0.25 and p = 0.86). Acetazolamide led to an increase of mean β and F values ( p = 0.18 and p = 0.025, respectively). It is possible to evaluate changes in brain perfusion through the intact skull by analyzing the UCA refill kinetics after US-induced microbubble destruction. (E-mail:seidel_g@neuro.mu-luebeck.de)

It is unclear if the dye-dilution theory and its corresponding parameters are capable of measuring brain perfusion using harmonic grey-scale imaging. We performed a study on a flow phantom using a SONOS 5500 (1.8--3.6-MHz harmonic imaging) and Levovist as the ultrasound (US) contrast agent (UCA). We applied the UCA in six different doses (0.1 to 3.0 mL) and used eight different flow-rates (180 to 540 mL/min). Additionally, we performed a study on dog brain using Levovist boluses of 1.5 mL and 3 mL. We evaluated the influence of dose and flow-rate on the parameters of the time-intensity curve: peak signal intensity (PSI), area under the curve (AUC) and mean transit time (MTT). Along with an increase of the Levovist dose, the AUC and the PSI increased only in the dose range between 0.1 and 0.5 mL Levovist; further increase led to no change of parameters. Flow-rate showed no influence on AUC, MTT or PSI. The dye-dilution theory is not a useful theoretical model for the analysis of perfusion using harmonic grey-scale imaging. A possible explanation for this effect is the bubble saturation.

The gut and brain peptide cholecystokinin (CCK) exerts a number of central nervous effects. Among them are effects on attention and stimulus processing as revealed by modulations of event-related potentials (ERPs). In the present study the time course of central nervous effects after an intranasal administration of CCK-8 was investigated by means of ERPs. ERPs were recorded in an oddball paradigm 15, 30, 60, 90, 120, and 240 min after administration. Following the double-blind intranasal administration of CCK-8 and placebo, the late positive complex (LPC) of the ERP was significantly increased following CCK-8 compared to placebo. This effect was more pronounced in women than in men. The enhancement of the LPC by intranasal CCK-8 was not restricted to a specific recording time but reached its maximum 120 min after administration in men and women. Moreover, results tentatively indicate that 30 min after administration of CCK-8 the LPC increased only in women but not in men. The early effect of intranasal CCK-8 on LPC in women is unlikely to be caused by changes in plasma CCK-8 levels and suggests a direct nose-brain pathway.

Die zuverlassige und schnelle Messung der zerebralen Mikrozirkulation ist entscheidend fur die Diagnose und Behandlung akuter zerebrovaskularer Erkrankungen. Die Perfusionsmessung mittels intrakranieller Ultraschallbildgebung bietet hierfur eine zeitsparende und mobil einsetzbare Alternative zu den aufwandigen tomographischen Verfahren. Der kombinierte Einsatz von Harmonic-Imaging Bildgebung und geeigneten Signalverstarkern erlaubt die Bestimmung der lokalen Hirnperfusion aus der Kontrastmittelkinetik uber ein Perfusionsmodell. Die resultierenden Flusbilder ermoglichen die schnelle Lokalisierung minderdurchbluteter Bereiche bei minimaler physischer und psychischer Patientenbelastung. Die diagnostische Relevanz der Flusbilder konnte in einer Probandenstudie nachgewiesen werden.

Background and Purpose —Through harmonic gray-scale imaging, it is possible to analyze brain tissue perfusion with different ultrasound methods. Methods —In 12 healthy volunteers, 2 doses (0.5 and 1.5 mL) of Optison, a perfluoropropane-containing contrast agent, were injected intravenously and produced a strong increase of brightness in the brain parenchyma. We used harmonic imaging for quantification of ultrasound intensity in the thalamus, ipsilateral temporoparietal white matter (TPWM), and ipsilateral lateral fissure at both sides. Time-intensity curves were calculated, and peak increase (PI) of intensity and the area under the time-intensity curve (AUC) from baseline were compared. Results —We found a significant dose dependence of the AUC in all regions at both sides. PI only showed a significant dose dependence in the TPWM but not in the ipsilateral thalamus and lateral fissure. No side differences for AUC and PI were detected in all regions and doses used. We found a significantly higher value of the PI insonating the thalamus from the ipsilateral side compared with the contralateral side. The same result was obtained for the AUC in the left thalamus for both doses and in the right thalamus for the high dose. Using 0.5 mL for insonation of the right thalamus AUC again showed a higher value for the insonation from the ipsilateral compared with the contralateral side but failed to show statistical significance ( P =0.08, n=12). Conclusions —Harmonic gray-scale imaging with Optison showed a strong enhancement effect in the brain parenchyma. A quantitative analysis of perfusion seems difficult because of the depth dependence of the effect. The most robust parameter is the AUC.

Die Darstellung und quantitative Auswertung der Hirnperfusion liefert wichtige diagnostische Hinweise. Mit der Computer-bzw. Magnet-Resonanz Tomographie stehen hierfur derzeit kosten- und zeitintensive Verfahren zur Verfugung. Demgegenuber stellt die Echo- densitometrie eine alternative, mobil einsetzbare Methode dar. Das dabei verwendete Ultraschallkontrastmittel besteht aus gasgefullten Mikroblaschen und bringt daher nur eine minimale Patientenbelastung mit sich. Verschiedene Faktoren schranken allerdings die Bildqualitat drastisch ein. Dieser Beitrag stellt eine neuartige Methode zur automatischen Quantifizierung der zerebralen Mikrozirkulation vor. Hierzu werden Harmonie Imaging Bildsequenzen mit stetig steigendem Aufnahmeintervall aufgenommen. Dadurch kann eine Sattigungskurve des Kontrastmittels im Blut ermittelt werden, aus deren Steigung sich die Flusgeschwindigkeit ergibt. Ein normiertes Mas fur die Hirnperfusion ist hieraus ableitbar. Weiterhin wird eine Verbesserung des Verfahrens vorgeschlagen, die auf den Musterspektrum der tiefpasgefilterten Bildsequenz basiert.