Sequencing of HLA-D in responders and nonresponders to short ragweed allergen,Amb a V

We investigated the molecular basis for the striking association between HLA-DR2,Dw2 and human immune responsiveness to the Ambrosia artemisiifolia (short ragweed) pollen allergen Amb a V by sequencing the second exons of the DRB and DQBI genes of 17 selected ragweed-allergic Caucasoid subjects. We also studied the DQA1 allelic polymorphic regions (APRs) in these patients by dot-blotting using sequence-specific oligonucleotides (SSOs). The deduced amino acid sequences of the respective class II and polypeptides were compared, with particular emphasis on residues in the APRs that are implicated in antigen binding. No evidence for new HLA-DRB or DQB sequences unique to Amb a V responders were found on sequencing seven Dw2⁺ subjects. This suggests that the presence of a particular Dw2-associated class II molecule usually provides a necessary, but not always sufficient condition for responsiveness to Amb a V. The HLA phenotypes of three subjects suggest that they possess novel recombinant haplotypes containing either DRB1 ^* 1501 and DRB5 ^* 0101 (Dr2.2-associated) or DQB1 ^* 0602 (DQ1.2-associated) sequences. In these subjects, responsiveness to Amb a V was associated with the DR2.2 but not the DQ1.2 sequences, suggesting that DR_I or DR_V class II molecules are involved in antigen presentation. We investigated whether there may be shared HLA-D-encoded responder sequences present in all responders, including some exceptional DR2^– Amb a V responders. The 13 subjects producing antibody (Ab) responses to Amb a V [either from natural exposure and/or after ragweed immunotherapy (Rx)] possessed DRB1 ^* 1501, 1601, 1602, 0103, 0402, 0404, 0801 or 1101 sequences, which share the majority of their aa residues in the APRs 2–4. Some of these shared residues might be important for the binding of a common Amb a V agretope prior to presentation of the class II Amb a V complex to the T-cell receptor (Tcr). An alternative postulate is that the recognition of two different Amb a V agretopes may be determined by the _I polypeptides of molecules having the DR2 and DQw3 specificities.     

Immunochemical and genetic studies of Amb.t. V (Ra5G), an Ra5 homologue from giant ragweed pollen

Giant ragweed pollen allergen Amb.t. V (Ra5G), a homologue of short ragweed pollen Amb.a. V (Ra5S), was isolated in ultrapure form from a 16-min extract of ragweed pollen by a combination of molecular sieving through an Amicon hollow fiber cartridge (H1P5), cation-exchange chromatography, and gel filtration. The size was found to be 4400 daltons (D) by amino acid analysis and 6000 D by SDS-PAGE, and the pI was 8.3 as determined by isoelectric focusing. There was no cross-reactivity detected between the two Amb. V antigens by immunodiffusion and IEP with the use of hyperimmune antisera raised against crude or highly purified antigens. Cross-reactivity between the two Amb. V antigens was further investigated by inhibition double antibody radioimmunoassay by using the sera of nine selected ragweed-allergic patients who had recently been immunized with either mixed short-giant ragweed pollen extract or with short ragweed extract alone and who had IgG antibodies (Ab) to Amb.t. V and generally to Amb.a. V. Unlabeled Amb.t. V did not inhibit the binding of 125I-Amb.a. V to the IgG Ab in any of the sera tested. Conversely, unlabeled Amb.a. V produced some inhibition of the binding of 125I-Amb.t. V to the patients' IgG Ab, primarily in those patients who had received immunotherapy with short ragweed alone. This weak cross-reactivity was probably a result of the primary structural homology between the two protein allergens. The sera from two groups of ragweed-allergic individuals were investigated for the presence of IgG and IgE Ab to Amb.t. V. The presence of IgG Ab was found to be associated both with previous (or current) immunotherapy with giant ragweed extract and with HLA-Dw2. The HLA association is of interest in view of the previously established association between Dw2 and response toward the homologue Amb.a. V. The result suggests the existence of a similar genetic control at the primary level of antigenic recognition of the two Amb. V antigens.     

Concentration of IgE in children during ragweed pollination season

Genetic and environmental factors are responsible for running allergic diseases. The aim of this study was to compare the values of total- (t-IgE) and allergen-specific IgE (s-IgE) to Ambrosia artemisiifolia L. (Amb a) in children with sensitization to Amb a during ragweed pollination season, who experienced seasonal symptoms of allergic rhinitis (rhinorrhea, post-nasal drip, nasal congestion, itching, sneezing) and asthma (coughing, especially at night, wheezing, shortness of breath, chest tightness). Ragweed pollen grains were collected in Virovitica (rural area) and Zagreb (urban area)—cities with the same geographical width and elevation—during ragweed pollination seasons (July–October in 2006 and 2007), and their count was estimated. Concentration of t-IgE and s-IgE in pollination season was determined in serum of children with symptoms of allergic diseases. The total count of ragweed pollen grains (PG) differed significantly between Virovitica and Zagreb in both years, 2006. and 2007. In Virovitica it was significantly greater than in Zagreb. There was no statistically significant seasonal difference in both, t-IgE and s-IgE, respectively. No correlation was found between pollen grain count and the concentration of IgE’s. To clarify the induction of IgE synthesis in children with sensitization to Amb a, further studies are needed.     

A New Allergen from Ragweed (Ambrosia artemisiifolia) with Homology to Art v 1 from Mugwort

Art v 1, the major pollen allergen of the composite plant mugwort (Artemisia vulgaris) has been identified recently as a thionin-like protein with a bulky arabinogalactan-protein moiety. A close relative of mugwort, ragweed (Ambrosia artemisiifolia) is an important allergen source in North America, and, since 1990, ragweed has become a growing health concern in Europe as well. Weed pollen-sensitized patients demonstrated IgE reactivity to a ragweed pollen protein of apparently 29–31 kDa. This reaction could be inhibited by the mugwort allergen Art v 1. The purified ragweed pollen protein consisted of a 57-amino acid-long defensin-like domain with high homology to Art v 1 and a C-terminal proline-rich domain. This part contained hydroxyproline-linked arabinogalactan chains with one galactose and 5 to 20 and more α-arabinofuranosyl residues with some β-arabinoses in terminal positions as revealed by high field NMR. The ragweed protein contained only small amounts of the single hydroxyproline-linked β-arabinosyl residues, which form an important IgE binding determinant in Art v 1. cDNA clones for this protein were obtained from ragweed flowers. Immunological characterization revealed that the recombinant ragweed protein reacted with >30% of the weed pollen allergic patients. Therefore, this protein from ragweed pollen constitutes a novel important ragweed allergen and has been designated Amb a 4.     

Binding parameters of monoclonal antibodies reacting with ovarian carcinoma ascites cells

Summary Binding parameters were determined for four mouse monoclonal antibodies reacting with three antigens on the surface of fresh human ovarian carcinoma ascites cells, under nearly physiological conditions. The object of these experiments was to aid in the selection of the optimal monoclonal antibodies for intraperitoneal immunotherapy. The number of antigenic sites per cell, the effective equilibrium association constant (affinity) and the half-life for dissociation were: for Ab MH99, 1.2×10⁶ sites/cell, (1.9–4.1)×10⁸M^–1, and 4 h; for Ab MX35, (3.2–4.1)×10⁵ sites/cell, (3.4–4.8)×10⁸M^–1, and >10 h; and for Ab MW207, 1.3×10⁵ sites/cell, (3.6–4.1)×10⁹M^–1, and 3.1 h, respectively. One of the antigens, MH99, is recognized by five different monoclonal antibodies, and competitive inhibition experiments demonstrated that two distinct determinants are present; this antigen is also recognized by the previously described Ab 17-1A. These binding data will aid the rational design of immunotherapy strategies.     

Phytoplankton pigments and adenosine triphosphate (ATP) in Lake Peipsi-Pihkva

The material for pigment analysis was collected 1–3 times a year from Lake Peipsi-Pihkva in 1983, 1987, 1988, 1991 and 1992–1995. Concentrations of chlorophyll a, b and c (Chla, Chlb, Chlc), pheopigment (Pheo) and adenosine triphosphate (ATP) were measured biweekly in 1985–1986. The mean of all Chla values was 20.2 mg m^–1 (median 13.3 mg m^–1) indicating the eutrophic state of the lake. Average Chlb, Chlc, Pheo and carotenoid (Car) contents were 3.7 mg m^–3, 4.1 mg m^–3, 3.0 mg m^–3 and 4.8 mg m^–3, respectively. The average Chlb/Chla ratio was 22.9%, Chlc/Chla 23.4%, Pheo/Chla 38%, Car/Chla 37% and ATP/Chla 3%, the medians being 14.3, 13.6, 17.5, 39.4 and 1.9%, respectively. The proportion of Chla in phytoplankton biomass was 0.41%, median 0.32%. There were no significant differences in temperature, oxygen concentration, Chla, and ATP between the surface and bottom water; the lake was polymictic during the vegetation period. The Chla concentration had its first peak in May followed by a decrease in June and July. In late summer Chla increased again achieving its seasonal maximum in late autumn. The ATP concentration was the highest during spring and early summer, decreasing drastically in autumn together with the decline of primary production. ATP/Chla was the highest during the clear water period in June and early July, which coincided also with the high proportion of Chla in phytoplankton biomass. The highest Chla occurred in November (average 37.2 mg m^–3) when Secchi transparency was the lowest (1.05 m). Concentrations of Chlb, Chlc and carotenoids were the highest in August, that of Pheo in June. Concentrations of Chla and other pigments were the lowest in the northern part of Lake Peipsi (mean 14.7 mg m^–3, median 12.5 mg m^–3) and the highest in the southern part of Lake Pihkva (mean 47.9 mg m^–3, median 16.3 mg m^–3). An increase of Chla and decrease of Secchi depth could be noticed in 1983–1988, while in 1988–1994 the tendency was opposite.     

Binding of Cu (II), Tb (III) and Fe (III) to chicken ovotransferrin

The kinetics of binding of Cu (II), Tb (III) and Fe(III) to ovotransferrin have been investigated using the stopped-flow technique. Rate constants for the second-order reaction, k ₊, were determined by monitoring the absorbance change upon formation of the metal-transferrin complex in time range of milliseconds to seconds. The N and C sites appeared to bind a particular metal ion with the same rate; thus, average formation rate constants k ₊ (average) were 2.4 × 10⁴ M^–1 s^–1 and 8.3 × 10⁴ M^–1 S ^–1 for Cu (II) and Tb (III) respectively. Site preference (N site for Cu (II) and C site for Tb (III)) is then mainly due to the difference in dissociation rate constant for the metals. Fe (III) binding from Fe-nitrilotriacetate complex to apo-ovotransferrin was found to be more rapid, giving an average formation rate constant k ₊ (average) of 5 × 10⁵ M^–1 s^–1, which was followed by a slow increase in absorbance at 465 nm. This slow process has an apparent rate constant in the range 3 s^–1 to 0.5 s^–1, depending upon the degree of Fe (III) saturation. The variation in the rate of the second phase is thought to reflect the difference in the rate of a conformational change for monoferric and diferric ovotransferrins. Monoferric ovotransferrin changes its conformation more rapidly (3.4s^–1) than diferric ovotransferrin (0.52 s^–1). A further absorbance decrease was observed over a period of several minutes; this could be assigned to release of NTA from the complex, as suggested by Honda et al. (1980).Abbreviations Tf ovotransferrin - NTA nitrilotriacetate Jichi Medical School, School of Nursing, Yakushiji 3311-159, Minamikawachi, Tochigi, 329-04 Japan     

Oxygen mass-transfer performance of low viscosity gas-liquid-solid system in a split-cylinder airlift bioreactor

The O₂ mass-transfer coefficient, k _L a, decreased by 20% when the viscosity of a simulated broth increased from 1.38 × 10^–3 to 3.43 × 10^–3 Pa s in a split-cylinder airlift bioreactor with a broth volume of 41 l. When the paper pulp concentration was below 10 g l^–1, k _L a hardly changed. While at 30 g l^–1, k _L a decreased by 56%. C₂O₄ ^2– and Na⁺ were found to have some effect on the k _L a value.     

Life in extreme environments: Investigations on the ecophysiology of a desert bird,the Australian Diamond Dove (Geopelia cuneata Latham)

Summary The Diamond Dove, Geopelia cuneata, is the world's second smallest (ca. 35 g) species of the columbid order. The Diamond Dove is endemic in the arid and semiarid Mulga and Spinifex regions of Central and Western Australia. It regularly encounters ambient temperatures (T _a ) in its habitat above +40° C, especially when foraging for seeds on bare ground cover, and may be found at up to 40 km from water. This entails extreme thermal stress, with evaporative cooling constrained by limited water supply. Energy metabolism (M), respiration, body temperature (T _a ) and water budget were examined with regard to physiological adaptations to these extreme environmental conditions. The zone of thermal neutrality (TNZ) extended from +34° C to at least +45° C. Basal metabolic rate (BMR) was 34.10±4.19 J g^–1h^–1, corresponding to the values predicted for a typical columbid bird. Thermal conductance (C) was higher than predicted. Geopelia cuneata showed the typical breathing pattern of doves, a combination of normal breathing at a stable frequency (ca. 60 min^–1) at low T _a and panting followed by gular flutter (up to 960 min^–1) at high T _a . At T _a > +36° C, T _a increased to considerably higher levels without increasing metabolic rate, i.e. Q₁₀=1. This enabled the doves not only to store heat but also to save the amout of water that would have been required for evaporative cooling if T _a had remained constant. The birds were able to dissipate more than 100% of the metabolic heat by evaporation at T _a +44° C. This was achieved by gular flutter (an extremely effective mechanism for evaporation), and also by a low metabolic rate due to the low Q₁₀ value for metabolism during increased T _b . At lower T _a , Geopelia cuneata predominantly relied on non-evaporative mechanisms during heat stress, to save water. Total evaporative water loss over the whole T _a range was 19–33% lower than expected. In this respect, their small body size proved to be an important advantage for successful survival in hot and arid environments.Abbreviations and units Body Mass W (g) - Ambient Temperature T _a (°C) - Body Temperature T _b (°C) - Thermoneutral Zone (TNZ) - Metabolism M (J g^–1 h^–1) - Thermal Conductance C - wet Thermal Conductance C _wet (J g^–1 h^–1 °C^–1) - Evaporative Water Loss EWL (mg H₂O g^–1 h^–1) - Evaporative Heat Loss EHL (J g^–1 h^–1) - Breathing Frequency F (breaths min^–1) - Tidal Volume V _t (ml breath^–1) - Standard Temperature Pressure Dry STPD - Body Temperature Pressure Saturated BTPS - Respiratory Quotient RQ - n.s. not significant (P>0.05) - n number of experiments     

Phytoplankton and zooplankton (Cladocera,Copepoda) relationship in the eutrophicated River Danube (Danubialia Hungarica,CXI)

The seasonal variation in primary production, individual numbers, and biomass of phyto- and zooplankton was studied in the River Danube in 1981. The secondary production of two dominant zooplankton species (Bosmina longirostris and Acanthocyclops robustus) was also estimated. In the growing season (April–Sept.) individual numbers dry weights and chlorophyll a contents of phytoplankton ranged between 30–90 × 10⁶ individuals, l^–1, 3–12 mg l^–1, and 50–170 µg l^–1, respectively. Species of Thalassiosiraceae (Bacillariophyta) dominated in the phytoplankton with a subdominance of Chlorococcales in summer. Individual numbers and dry weights of crustacean zooplankton ranged between 1400–6500 individuals m^–3, and 1.2–12 mg m^–3, respectively. The daily mean gross primary production was 970 mg C m^–3 d^–1, and the net production was 660 mg C m^–3 d^–1. Acanthocyclops robustus populations produced 0.2 mg C m^–3 d^–1 as an average, and Bosmina longirostris populations 0.07 mg C m^–3 d^–1. The ecological efficiency between phytoplankton and crustacean zooplankton was 0.03%.     

Colonization potential of bacteria in the rhizosphere

The effect of inoculum density on growth and steady-state populations of aPseudomonas sp., aMycoplana sp., and aCurtobacterium sp. in the rhizosphere if gnotobiotic barley plants was studied. Inoculation of sterile barley seedling at concentrations of about 1×10³, 1×10⁵ and 1×10⁷ viable cells (mg dry wt root)^–1 resulted in rapid colonization; maximum populations of about 5×10⁷ viable cells (mg dry wt root)^–1 developed in each case. We define this maximum population as the colonization potential. Measurement of growth of known rhizosphere bacteria might be a useful index of the amount of available carbon and energy lost by growing roots.     

A simple method for mass isolation of protoplasts from species of Monostroma, Enteromorpha and Ulva (Chlorophyta, Ulvales)

A simple enzyme mixture containing 2% Cellulase Onozuka R–10 and1% Macerozyme R–10 prepared in deionised water supplemented with 3% NaCland 1 mM CaCl₂ was developed for isolating rapidlyprotoplasts from different species of Monostroma,Enteromorpha and Ulva. The yield fordifferent species of Monostroma ranged from 9.6 ×10⁶ to 10.2 × 10⁶ cells g^–1f. wt thallus, and forEnteromorpha from 3.48 × 10⁶ to 11.7× 10⁶ cells g^–1 f. wt and forUlva from 4.58 × 10⁶ to 26.8 ×10⁶ cells g^–1 f. wt. The overallregeneration rate of the protoplasts isolated was usually > 90% and showednormal morphogenesis. The method yields rapid mass production of viableprotoplasts with high regeneration rates.     

Selective ingestion of phytoplankton by the bivalvesMytilus edulis L. andCerastoderma edule (L.)

Blue mussles (Mytilus edulis) and cockles (Cerastoderma edule) were collected in the Oosterschelde estuary (SW Netherlands) and exposed to diets consisting of the diatomPhaeodactylum tricornutum and silt. Algal concentrations were kept constant (20.10³ cells.ml^–1), and silt concentrations were varied between 3–80 mg.l^–1 (mussel experiments) and 20–120 mg.l^–1 (cockle experiments). Chlorophyll-a concentrations in the pseudofaeces were reduced compared to the diets, indicating selective ingestion of the algae. It was estimated that the mussels increase the ingestion of chlorophyll-a 2.0 times, and the cockles increase the chlorophyll-a ingestion 2.8 times, compared to the ingestion rate without selection. The selection coefficients were not affected by the SPM concentrations used. Phaeophytin-a concentrations in the faeces showed an increase as a consequence of the digestion of the ingested algae. Digestive efficiencies of chlorophyll-a varied between 36–92% The digestive efficiencies decreased with increasing SPM concentrations.Communication no. 541 of the Delta Institute for Hydrobiological Research.     

Host plant population density and distribution pattern as factors limiting geographic distribution of the ragweed leaf beetle <Emphasis Type="Italic">Zygogramma suturalis</Emphasis> F. (Coleoptera,Chrysomelidae)

Field sampling conducted in 2005–2007 in Voronezh and Rostov provinces and in Stavropol and Krasnodar territories (south-west of European Russia) suggested that the climatic effect on geographic distribution of the ragweed leaf beetle, Zygogramma suturalis is mediated by the abundance of its host plant, Ambrosia artemisiifolia. At the periphery of the common ragweed invasion area Z. suturalis was absent or its population density was below the detection threshold. A pivotal role was played by the sufficient percentage of small but relatively stable plots with high ragweed population density, rather than by the mean rate of the ragweed infestation. Inside the geographic range of the ragweed leaf beetle all relatively stable habitats were infested by A. artemisiifolia and in more than half of plots inspected, common ragweed percent cover was higher than 5%. In regions where such infestation was recorded on less than 20% of the plots studied, Z. suturalis was absent, most likely due to its low ability for long-range search for a host plant.     

Energy metabolism, nocturnal torpor, and respiration frequency in a Green Hermit (Phaethornis guy)

Zusammenfassung Beim Grünen Schattenkolibri (Phaethornis guy) lag die Relation zwischen Energiestoffwechsel (M) und Umgebungstemperatur (T_a) geringfügig unter den nach der Körpermasse (W) zu erwartenden Werten. Am Tage (T_a: 25°C) betrug die Korrelation M (kJ h^–1)=0,708×W (g)^0,54, nachts (einschließlich der Torporwerte) M=0,212×W^0.76. Tiefster Torporwert war 9 J g^–1 h^–1 (nachts, 15°C). M im Torpor verlief linear zur Umgebungstemperatur (M=–27,2+2,2 T_a, r=0,92). Die Atemfrequenz in der Photophase betrug 2,33±0,18 s^–1 (n=105), nachts (Torpor unberücksichtigt) 0,6±0,2 s^–1 (n=15). Die O₂-Aufnahme pro Atemzug betrug 8,2 µl in der aktiven und 4,9 µl in der inaktiven Phase. Die Meßwerte zeigen, daßPhaethornis guy, ein Vertreter der Unterfamilie Phaethornithinae, sich in Energiestoffwechsel, Torpor und Atemfrequenz von den bisher untersuchten Trochilinae nicht unterscheidet.     

Removal of Cr(VI) from ground water by Saccharomyces cerevisiae

Chromium can be removed from ground water by the unicellular yeast, Saccharomyces cerevisiae. Local ground water maintains chromium as CrO₄ ^2- because of bicarbonate buffering and pH and E _h conditions (8.2 and +343 mV, respectively). In laboratory studies, we used commercially available, nonpathogenic S. cerevisiae to remove hexavalent chromium [Cr(VI)] from ground water. The influence of parameters such as temperature, pH, and glucose concentration on Cr(VI) removal by yeast were also examined. S. cerevisiae removed Cr(VI) under aerobic and anaerobic conditions, with a slightly greater rate occurring under anaerobic conditions. Our kinetic studies reveal a reaction rate (V_max) of 0.227 mg h^-1 (g dry wt biomass)^-1 and a Michaelis constant (Km) of 145 mg/l in natural ground water using mature S. cerevisiae cultures. We found a rapid (within 2 minutes) initial removal of Cr(VI) with freshly hydrated cells [55–67 mg h^-1 (g dry wt biomass)^-1] followed by a much slower uptake [0.6–1.1 mg h^-1 (g dry wt biomass)^-1] that diminished with time. A materials-balance for a batch reactor over 24 hours resulted in an overall shift in redox potential from +321 to +90 mV, an increase in the bicarbonate concentration (150–3400 mg/l) and a decrease in the Cr(VI) concentration in the effluent (1.9-0 mg/l).     

Reevaluation of biosecurity of Ophraella communa against sunflower (Helianthus annuus)

Ophraella communa (Coleoptera: Chrysomelidae), originally from North America, has been used for biological control of common ragweed, Ambrosia artemisiifolia, in China since 2007. However, there is still a debate on whether O. communa can attack sunflowers under field conditions. To re-evaluate the biosecurity of O. communa against sunflower (Helianthus annuus), we investigated the population density of O. communa on three sunflower varieties that were intercropped with or planted in circumambience of A. artemisiifolia under field conditions. Our results showed that only very few O. communa eggs (<0.5 eggs/plant) were found on sunflower plants at the last two surveys when sunflowers were planted in circumambience of common ragweed. O. communa eggs were not found on sunflower plants at each survey when sunflowers were intercropped with common ragweed. The first–second instar larvae, third instar larvae, pupae and adults of O. communa were occasionally found on sunflower plants, but their densities were very low under either case of planting patterns. Based on these results, we conclude that sunflower is not a potential host plant for O. communa and the beetle is an effective host-specific biological control agent of common ragweed.     

No carrier added synthesis of O-(2'-[18F]fluoroethyl)-L-tyrosine via a novel type of chiral enantiomerically pure precursor, NiII complex of a (S)-tyrosine Schiff base

O-(2′-[¹⁸F]fluoroethyl)-l-tyrosine ([¹⁸F]FET) has gained much attention as a promising amino acid radiotracer for tumor imaging with positron emission tomography (PET) due to favorable imaging characteristics and relatively long half-life of ¹⁸F (110 min) allowing remote-site application. Here we present a novel type of chiral enantiomerically pure labeling precursor for [¹⁸F]FET, based on NiII complex of a Schiff’s base of (S)-[N-2-(N′-benzylprolyl)amino]benzophenone (BPB) with alkylated (S)-tyrosine, Ni-(S)-BPB-(S)-Tyr-OCH2CH2X (X = OTs (3a), OMs (3b) and OTf (3c)). A series of compounds 3a–c was synthesized in three steps from commercially available reagents. Non-radioactive FET as a reference was prepared from 3a in a form of (S)-isomer and (R,S) racemic mixture. Radiosynthesis comprised two steps: (1) n.c.a. nucleophilic fluorination of 3a–c (4.5–5.0 mg) in the presence of either Kryptofix 2.2.2.or tetrabutylammonium carbonate (TBAC) in MeCN at 80 °C for 5 min, followed by (2) removal of protective groups by treating with 0.5 M HCl (120 °C, 5 min). The major advantages of this procedure are retention of enantiomeric purity during the ¹⁸F-introduction step and easy simultaneous deprotection of amino and carboxy moieties in 3a–c. Radiochemically pure [¹⁸F]FET was isolated by semi-preparative HPLC (C18 μ-Bondapak, Waters) eluent aq 0.01 M CH₃COONH₄, pH 4/C₂H₅OH 90/10 (v/v). Overall synthesis time operated by Anatech RB 86 laboratory robot was 55 min. In a series of compounds 3a–c, tosyl derivative 3a provided highest radiochemical yield (40–45%, corrected for radioactive decay). Enantiomeric purity was 94–95% and 96–97%, correspondingly, for Kryptofix and TBAC assisted fluorinations. The suggested procedure involved minimal number of synthesis steps and suits perfectly for automation in the modern synthesis modules for PET radiopharmaceuticals. Preliminary biodistribution study in experimental model of turpentine-induced aseptic abscess and Glioma35 rat’s tumor (homografts) in Wistar rats has demonstrated the enhanced uptake of radiotracer in the tumor area with minimal accumulation in the inflamed tissues.     

Analysis of leaf-rolling behavior ofCaloptilia serotinella (Lepidoptera: Gracillariidae)

The caterpillarCaloptilia serotinella generates the force required to roll leaves by stretching the silk strands it fixes between opposable plant surfaces. The Young's modulus of strands drawn by caterpillars at an average rate of 16 mm s^–1 was 1.1×10⁸ N m^–2. Single strands stretched in a tensiometer had a final Young's modulus of 1.4×10⁹ N m^–2 and withstood a maximum force of 60 × 10^–5 N (i.e., a 60-mg force) before breaking at 30% extension. Strands stretched approximately 14% beyond their equilibrium length by rolling caterpillars exerted an average axially retractive force of 3.2×10^–5 N and drew the leaf 7×10^–3 mm into the roll. During episodes of rolling, the caterpillars spun hundreds of strands capable of generating a collective force in excess of 0.1 N. Potential forces associated with wet contraction of strands were not harnessed by the caterpillar when rolling but subsequent supercontraction of the strands caused them to bind the roll tightly. Caterpillars appeared to facilitate leaf rolling by weakening the midrib with their mandibles.