100 research outputs found
Drosophila tan Encodes a Novel Hydrolase Required in Pigmentation and Vision
Many proteins are used repeatedly in development, but usually the function of the protein is similar in the different contexts. Here we report that the classical Drosophila melanogaster locus tan encodes a novel enzyme required for two very different cellular functions: hydrolysis of N-β-alanyl dopamine (NBAD) to dopamine during cuticular melanization, and hydrolysis of carcinine to histamine in the metabolism of photoreceptor neurotransmitter. We characterized two tan-like P-element insertions that failed to complement classical tan mutations. Both are inserted in the 5′ untranslated region of the previously uncharacterized gene CG12120, a putative homolog of fungal isopenicillin-N N-acyltransferase (EC 2.3.1.164). Both P insertions showed abnormally low transcription of the CG12120 mRNA. Ectopic CG12120 expression rescued tan mutant pigmentation phenotypes and caused the production of striking black melanin patterns. Electroretinogram and head histamine assays indicated that CG12120 is required for hydrolysis of carcinine to histamine, which is required for histaminergic neurotransmission. Recombinant CG12120 protein efficiently hydrolyzed both NBAD to dopamine and carcinine to histamine. We conclude that D. melanogaster CG12120 corresponds to tan. This is, to our knowledge, the first molecular genetic characterization of NBAD hydrolase and carcinine hydrolase activity in any organism and is central to the understanding of pigmentation and photoreceptor function
Effekt van multifasenvoedering op de stikstofuitscheiding en technische resultaten van vleesvarkens
Uit een onderzoek dat is uitgevoerd door het ID-DL0 IWO op het Varkensproefbedrijf te Sterksel blijkt dat het mogelijk is om vleesvarkens te voeren met behulp van multifasenvoedering. In de 'laag re'-groep is de N-uitscheiding 14% lager dan in de controlegroe
Bis(triphenylguanidinium) tetrachloridocuprate(II)
The structure of the title compound, (C19H18N3)2[CuCl4], consists of square-planar [CuCl4]2− anions and triphenylguanidinium cations. The CuII ion occupies a crystallographic inversion centre. In the cation, the dihedral angles between the phenyl rings and the plane defined by the central guanidinium fragment are in the range 51.9 (4)–64.4 (3)°. N—H⋯Cl hydrogen bonds assemble the ions into infinite chains running along the b axis
First delivery of a COVID-19 positive patient in Cameroon
Since its appearance in China in December 2019, COVID-19 which is caused by the SARS-CoV-2 virus has become a real global health problem. Pregnant women are not immune to this novel infection, which makes it difficult for proper management of pregnancy and childbirth. Authors present here the first case of childbirth in Cameroon of a 19-year-old adolescent tested positive for COVID-19
Interobserver variability in target definition for stereotactic arrhythmia radioablation
BackgroundStereotactic arrhythmia radioablation (STAR) is a potential new therapy for patients with refractory ventricular tachycardia (VT). The arrhythmogenic substrate (target) is synthesized from clinical and electro-anatomical information. This study was designed to evaluate the baseline interobserver variability in target delineation for STAR.MethodsDelineation software designed for research purposes was used. The study was split into three phases. Firstly, electrophysiologists delineated a well-defined structure in three patients (spinal canal). Secondly, observers delineated the VT-target in three patients based on case descriptions. To evaluate baseline performance, a basic workflow approach was used, no advanced techniques were allowed. Thirdly, observers delineated three predefined segments from the 17-segment model. Interobserver variability was evaluated by assessing volumes, variation in distance to the median volume expressed by the root-mean-square of the standard deviation (RMS-SD) over the target volume, and the Dice-coefficient.ResultsTen electrophysiologists completed the study. For the first phase interobserver variability was low as indicated by low variation in distance to the median volume (RMS-SD range: 0.02–0.02 cm) and high Dice-coefficients (mean: 0.97 ± 0.01). In the second phase distance to the median volume was large (RMS-SD range: 0.52–1.02 cm) and the Dice-coefficients low (mean: 0.40 ± 0.15). In the third phase, similar results were observed (RMS-SD range: 0.51–1.55 cm, Dice-coefficient mean: 0.31 ± 0.21).ConclusionsInterobserver variability is high for manual delineation of the VT-target and ventricular segments. This evaluation of the baseline observer variation shows that there is a need for methods and tools to improve variability and allows for future comparison of interventions aiming to reduce observer variation, for STAR but possibly also for catheter ablation
Start early! Does social instability during the pre- and early postnatal development prepare male wild cavies for social challenge later in life?
Effekt van multifasenvoedering op de stikstofuitscheiding en technische resultaten van vleesvarkens
Uit een onderzoek dat is uitgevoerd door het ID-DL0 IWO op het Varkensproefbedrijf te Sterksel blijkt dat het mogelijk is om vleesvarkens te voeren met behulp van multifasenvoedering. In de 'laag re'-groep is de N-uitscheiding 14% lager dan in de controlegroe
- …