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Photosynthate translocation from leaves to fruits is an important determinant of crop yield and quality. In protected cultivation, environmental control based on photosynthate translocation is indicative for realising high-yield and high-quality production. There are, however, few studies on the environmental response of photosynthate translocation, especially during twilight. In greenhouses, these transition periods are charac-terised by a drastic change in relative humidity (RH). In this study, we focused on light intensity as a key environmental factor to steer translocation under high RH prevailing under twilight conditions. We fed (CO2)-C-11 to a leaf of strawberry plants (Fragaria x ananassa Duch.) and analysed real-time dynamics of C-11-labeled photo-synthate translocation to individual fruits on an inflorescence of intact plants by using positron emission to-mography (PET) under different light intensities (i.e., 50, 200 and 400 mu mol m(-2) s(-1)). No clear relationship was obtained between 11C-photosynthate translocation and light intensity since the results revealed that trans-location rates into the fruits were highest under the light intensity of 200 mu mol m(-2) s(-1) followed by those of 400 and 50 mu mol m(-2) s(-1). However, there was a strong negative correlation between transpiration rate of the C-11-fed leaf and C-11-photosynthate translocation rate. These novel findings indicate that transpiration, which controls leaf moisture status, is one of the drivers for photosynthate translocation towards fruits during twilight conditions.

A wide variety ofsup18/supF-labeled PSMA-targeting PET radiotracers have been developed, including [sup18/supF]AlF-PSMA-11. As there is only limited data on the comparison with othersup18/supF-labeled PSMA PET tracers, a comparative preclinical study between [sup18/supF]AlF-PSMA-11 and [sup18/supF]PSMA-1007 was conducted. Mice with varying PSMA expressing tumors (C4-2, 22Rv1 and PC-3, each n = 5) underwent two PET/CT scans with both [sup18/supF]AlF-PSMA-11 and [sup18/supF]PSMA-1007. Ten additional mice bearing C4-2 xenografts were subjected to ex vivo biodistribution with either [sup18/supF]AlF-PSMA-11 (n = 5) or [sup18/supF]PSMA-1007 (n = 5). Absolute SUVsubmean/suband SUVsubmax/subvalues were significantly higher for [sup18/supF]PSMA-1007 scans in both C4-2 tumors (p lt; 0.01) and 22Rv1 tumors (p lt; 0.01). In C4-2 xenograft bearing mice, the tumor-to-organ ratios did not significantly differ between [sup18/supF]AlF-PSMA-11 and [sup18/supF]PSMA-1007 for liver, muscle, blood and salivary glands (p gt; 0.05). However, in 22Rv1 xenograft bearing mice, all tumor-to-organ ratios were higher for [sup18/supF]AlF-PSMA-11 (p lt; 0.01). In healthy organs, [sup18/supF]PSMA-1007 uptake was higher in the liver, gallbladder, small intestines and glands. Biodistribution data confirmed the increased uptake in the heart, small intestines and liver with [sup18/supF]PSMA-1007. Absolute tumor uptake was higher with [sup18/supF]PSMA-1007 in all tumors. Tumor-to-organ ratios did not differ significantly in high PSMA expressing tumors, but were higher for [sup18/supF]AlF-PSMA-11 in low PSMA expressing tumors. Furthermore, [sup18/supF]PSMA-1007 showed higher uptake in healthy organs.

Repetitive transcranial magnetic stimulation (rTMS) has been proven to be a useful tool for the treatment of several severe neuropsychiatric disorders. Accelerated (a)rTMS protocols may have the potential to result in faster clinical improvements, but the effects of such accelerated paradigms on brain function remain to be elucidated.This sham-controlled arTMS study aimed to evaluate the immediate and delayed effects of accelerated high frequency rTMS (aHF-rTMS) on glucose metabolism in healthy beagle dogs when applied over the left frontal cortex.Twenty-four dogs were randomly divided into four unequal groups: five active (One day of active aHF-rTMS- and not sham- significantly increased glucose metabolism 24 h post-active stimulation in the left frontal cortex only. Four days of active aHF-rTMS only resulted in a nearly significant metabolic decrease in the left hippocampus after 1 month.Like in human psychiatric disorders, active aHF-rTMS in healthy beagles modifies glucose metabolism, although differently immediately or after 1 month post stimulation. aHF-rTMS may be also a valid option to treat mentally disordered dogs.

Respired CO2 in woody tissues can build up in the xylem and dissolve in the sap solution to be transported through the plant. From the sap, a fraction of the CO2 can either be radially diffuse to the atmosphere or be assimilated in chloroplasts present in woody tissues. These processes occur simultaneously in stems and branches, making it difficult to study their specific dynamics. Therefore, an 11C-enriched aqueous solution was administered to young branches of Populus tremula L., which were subsequently imaged by positron emission tomography (PET). This approach allows in vivo visualization of the internal movement of CO2 inside branches at high spatial and temporal resolution, and enables direct measurement of the transport speed of xylem-transported CO2 (vCO2). Through compartmental modeling of the dynamic data obtained from the PET images, we (i) quantified vCO2 and (ii) proposed a new method to assess the fate of xylem-transported 11CO2 within the branches. It was found that a fraction of 0.49 min−1 of CO2 present in the xylem was transported upwards. A fraction of 0.38 min−1 diffused radially from the sap to the surrounding parenchyma and apoplastic spaces (CO2,PA) to be assimilated by woody tissue photosynthesis. Another 0.12 min−1 of the xylem-transported CO2 diffused to the atmosphere via efflux. The remaining CO2 (i.e., 0.01 min−1) was stored as CO2,PA, representing the build-up within parenchyma and apoplastic spaces to be assimilated or directed to the atmosphere. Here, we demonstrate the outstanding potential of 11CO2-based plant-PET in combination with compartmental modeling to advance our understanding of internal CO2 movement and the respiratory physiology within woody tissues.

Objectives We report a reproducible automated radiosynthesis for large scale batch production of clinical grade Al[18F]PSMA-11. Methods A SynthraFCHOL module was optimized to synthesize Al[18F]PSMA-11 by Al[18F]-chelation. Results Al[18F]PSMA-11 was synthesized within 35 min in a yield of 21 ± 3% (24.0 ± 6.0 GBq) and a radiochemical purity > 95%. Batches were stable for 4 h and conform the European Pharmacopeia guidelines. Conclusions The automated synthesis of Al[18F]PSMA-11 allows for large scale production and distribution of Al[18F]PSMA-11.

Phloem transport is of great importance in trees to distribute assimilated carbon across the entire tree. Nevertheless, knowledge of phloem is incomplete, because of the complexity of measuring its transport and characteristics. Only few studies have addressed how phloem transport might alter under climatic changes, with most data originating from theoretical studies. We measured phloem characteristics in leaves of young Populus tremula L. trees grown during 5 months under ambient (T-A, 404 ppm +/- 5) and elevated (T-E, 659 ppm +/- 3) atmospheric CO2 concentration ([CO2]) using a combination of positron emission tomography (PET) and compartmental modelling. Short-term phloem dynamics were measured in vivo and non-invasively using the short-lived isotope of carbon, C-11 (half-life 20.4 min). Trees were scanned in well-watered and dry conditions to assess changes in phloem characteristics induced by drought. Reliability of the PET-derived results was verified with reported observations in the literature. Phloem speed was highest in well-watered T-E trees and strongly reduced by 81% under drought, whereas phloem speed reduced by 61% in T-A trees at the same level of drought. These findings led us to speculate that phloem transport in T-E trees might be more vulnerable to drought. We discuss how a higher phloem vulnerability to drought in a changing climate could impact tree hydraulic functioning. Taken together our results suggest that trees grown for 5 months under elevated [CO2] seem to be less well-acclimated to face projected hotter droughts in a changing climate.

We report a reproducible automated radiosynthesis for large scale batch production of clinical grade Al[A SynthraFCHOL module was optimized to synthesize Al[The automated synthesis of Al[

A method for labelling acamprosate (calcium N-acetyl homotaurinate), an anti-craving compound for ethanol, with 11C, has been developed for in vivo studies with positron emission tomography (PET). The synthesis was based on the acylation of homotaurinate using [11C]acetyl chloride as the labelling agent. Reversed-phase HPLC in highly aqueous mobile phase conditions was used for product purification. The radiochemical yield achieved was about 1.14 GBq (31 mCi) with a specific radioactivity of 8.14 GBq/µmol (220 mCi/µmol). For the identification of 11C-radioactivity and determination of specific radioactivities, HPLC and 1H-NMR were used. Copyright © 2001 John Wiley & Sons, Ltd.

Acetylhomotaurine was labeled with (11)C via N-acetylation with [(11)C]acetyl chloride. The synthesis yielded 48.2+/-3.8%, decay corrected to end of bombardment. The specific activity of the (radio)chemically pure product was 20.8+/-2.0 GBq/micromol at EOS. In vivo studies revealed a very fast clearance of the tracer from the blood and a uniform distribution in the different brain regions. Unfortunately, the poor passage through the blood brain barrier makes the tracer not suitable for PET studies.