Recruiting future neuroscientists: what asking the recruits can teach us.

Many different strategies are used to recruit students into scientific research careers, including neuroscience research. These strategies are rarely based on knowledge about students; instead, activities are selected based on their ease of implementation. The goal of the LEARN Project is to encourage high school students into mental health science research using the theme of learning and memory. One intervention the authors developed is five Web-based biographies introducing students to contemporary neuroscientist role models studying learning and memory. To guide the design of this intervention, the authors created a survey to determine where students obtain career information and who and what influences their career selection. In a convenience sample of 124 students, the authors found that almost all students use the Internet for information about careers, in addition to consulting family members and teachers. Students' career selections are influenced most by family members, teachers, and people already in the field. The most important factors students look for in their future career are money, fun, and a good match between current interests and future careers. The data affirm the value of outreach efforts that go beyond students to include a broader audience of parents and teachers who play a critical role in career selection.     

Dual effects of spinally delivered 8-bromo-cyclic guanosine mono-phosphate (8-bromo-cGMP) in formalin-induced nociception in rats

Interactions are known to occur in the brain between serotonin (5-HT) and substance P (SP). To investigate whether SP can directly influence serotonergic neurons, double immunohistochemical labelings were performed on rat brain sections with NK1 or NK3 affinity-purified antibodies and a 5-HT monoclonal antibody. It was found that the vast majority of serotonergic cell bodies do not colocalize NK1 or NK3 labeling. Only in the central linear nucleus and ventral part of the dorsal raphe nucleus were a few serotonergic neurons double-labeled for NK1 receptors (15 and 0.8% of serotonergic neurons, respectively). It is suggested that serotonergic neurons are not major direct targets for SP in the rat brain.     

Dodecon,das lösliche Hämagglutinin bei allen Adenoviren der Untergruppe II

Zusammenfassung Die Sedimentationsraten der kompletten löslichen Hämagglutinine der Adenoviren wurden bei 16 Prototypen der Untergruppe II im Saccharose-Gradienten bestimmt. Die Werte waren für alle Viren ähnlich (65±10S). Dies bedeutet, daß die strukturellen Komponenten ebenfalls identisch sein dürften, also Dodecon (1).

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Dodecon, the soluble hemagglutinin present in all adenovirus types of subgroup II

Summary The sedimentation rate of the soluble complete hemagglutinins of 16 prototype adenoviruses of subgroup II were determined by means of sucrose gradient centrifugation. The rates were similar for all types (65±10S), thus indicating that the structural components may also be identicali.e. dodecon (1).

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Durchgeführt mit Unterstützung der Deutschen Forschungsgemeinschaft.     

Flow cytometric analysis of cell proliferation dynamics in the B cell compartment of the mouse

Using a method which allows simultaneous flow cytometric detectionof cell surface markers and 5-bromo-2'-deoxyuridine (BrdU) incorporation,the distribution and proliferative behavior of B lineage subpopulationswas studied in intact adult mice. In the bone marrow we coulddefine two subsets of B cells on the basis of differential expressionof the pan-B cell marker B220 and of membrane-associated µand immunoglobulin heavy chains. B220^dullµ^+– Bcells were found to emerge from rapidly dividing cells and probablyrepresent B cells recently generated from B220^dullµ^–pie-B cells. In contrast, oniy few, If any, of the B220^brightµ⁺⁺B cells were labeled with BrdU after a period of 8 days, suggestingthat these cells represent long-lived B cells residing in thebone marrow. Analysis of BrdU-Incorporation into splenic B cellsshowed that only 20% of these cells had gone through cell divisionduring the preceding 8 days. Almost none of the B cells in theperitoneum, a large fraction of which belongs to the Ly1 B subset,were labeled with BrdU over a period of 7 days in 8-month-oldanimals.     

Dosimetric characteristics of a new unshielded silicon diode and its application in clinical photon and electron beams

Shielded p-silicon diodes, frequently applied in general photon-beam dosimetry, show certain imperfections when applied in the small photon fields occurring in stereotactic or intensity modulated radiotherapy (IMRT), in electron beams and in the buildup region of photon beam dose distributions. Using as a study object the shielded p-silicon diode PTW 60008, well known for its reliable performance in general photon dosimetry, we have identified these imperfections as effects of electron scattering at the metallic parts of the shielding. In order to overcome these difficulties a new, unshielded diode PTW 60012 has been designed and manufactured by PTW Freiburg. By comparison with reference detectors, such as thimble and plane-parallel ionization chambers and a diamond detector, we could show the absence of these imperfections. An excellent performance of the new unshielded diode for the special dosimetric tasks in small photon fields, electron beams and build-up regions of photon beams has been observed. The new diode also has an improved angular response. However, due to its over-response to low-energy scattered photons, its recommended range of use does not include output factor measurements in large photon fields, although this effect can be compensated by a thin auxiliary lead shield.     

Validity of "generalized" equations for body composition analysis in male athletes

Equations by Durnin and Womersley [(D-W), Br. J. Nutr. 32:77, 1974], Jackson and Pollock [(J-P), Br. J. Nutr. 40:497, 1978], and Lohman [(L), Human Biol., 53:181, 1981] for estimating body density (BD) purportedly overcome the problem of specificity by accounting for age and/or the curvilinear relationship between skinfolds (SF) and BD. Their equations were validated on 265 male athletes against percent fat measured by underwater weighing [(UWW); mean +/- SD = 9.2 +/- 4.4%]. Equations by Sloan [(S), J. Appl. Physiol. 23:311, 1967], Katch and McArdle [(K-M), Human. Biol. 45:445, 1973], and Forsyth and Sinning [(F-S), Med. Sci. Sports 5:174, 1973] were included as "linear regression models" to compare to the curvilinear models of J-P, D-W, and L. Differences between UWW and estimated mean values ranged from -1.1 to +5.9%; correlations ranged from 0.58 to 0.85; SEE ranged from +/- 2.41 to +/- 3.61% and total error (E) ranged from 2.38 to 6.97%. The seven D-W equations overestimated mean percent fat by from 3.9 to 5.9%. The K-M, S, and L equations overestimated by 1.3, 0.5, and 1.7%, respectively. The F-S equations overestimated by 2.4 to 3.8%. Of the 21 equations evaluated, only 3 by J-P gave estimates not significantly different from UWW percent fat. Regression analyses of the relationship between UWW (y) and estimated (x) percent fat values from those equations were: y = 1.037x - 0.08 +/- 2.38, E = 2.38, r = 0.84; 0.869x + 1.36 +/- 2.45, E = 2.51, r = 0.83; 1.107x - 1.14 +/- 2.51, E = 2.53, r = 0.82.(ABSTRACT TRUNCATED AT 250 WORDS)     

Urinary pharmacokinetics of betalains following consumption of red beet juice in healthy humans.

The aim of the present pilot study was to characterise the renal elimination of betalains after consumption of red beet juice (RBJ). Six healthy, non-smoking female volunteers were given a single oral dose of either 500 mL of a commercial RBJ containing 362.7 mg of betalains and 500 mL of tap water, respectively, in a sequential manner. Urine was collected in intervals up to 24 h post-dose. Renal excretion of betalains was determined spectrophotometrically and quantified as betanin-equivalents. In addition, the identity of individual compounds was confirmed by HPLC coupled with diode-array detection and positive ion electrospray mass spectrometry, respectively. The amount (mean+/-S.D.) of intact betalains (betanin and isobetanin) recovered in urine was 1001+/-273 microg corresponding to 0.28+/-0.08% of the administered dose. Maximum excretion rates were observed after a median tmax,R of 3.0 h (range 2.5-8.0 h) amounting to 91.7+/-30.1 microg/h. The terminal elimination rate constant (lambdaz) and the corresponding half-life were 0.097+/-0.021 h(-1) and 7.43+/-1.47 h, respectively. Using the lambdaz estimates obtained the expected total betalain amount excreted in urine was 1228+/-291 microg. Based on the results obtained it is assumed that either the bioavailability of the betalains is low or that renal clearance is a minor route of systemic elimination for these compounds. The urinary excretion rates of unmetabolised betalains were fast and appeared to be monoexponential suggesting a one-compartment model. In order to get a more complete picture of the pharmacokinetics and health-promoting properties of red beet betalains, quantitative data on betalain bioavailability should include measurements of unchanged compounds and their corresponding metabolites in plasma, urine and bile.