Substantial Differences between Organ and Muscle Specific Tracer Incorporation Rates in a Lactating Dairy Cow

We aimed to produce intrinsically L-[1-¹³C]phenylalanine labeled milk and beef for subsequent use in human nutrition research. The collection of the various organ tissues after slaughter allowed for us to gain insight into the dynamics of tissue protein turnover in vivo in a lactating dairy cow. One lactating dairy cow received a constant infusion of L-[1-¹³C]phenylalanine (450 µmol/min) for 96 h. Plasma and milk were collected prior to, during, and after the stable isotope infusion. Twenty-four hours after cessation of the infusion the cow was slaughtered. The meat and samples of the various organ tissues (liver, heart, lung, udder, kidney, rumen, small intestine, and colon) were collected and stored. Approximately 210 kg of intrinsically labeled beef (bone and fat free) with an average L-[1-¹³C]phenylalanine enrichment of 1.8±0.1 mole percent excess (MPE) was obtained. The various organ tissues differed substantially in L-[1-¹³C]phenylalanine enrichments in the tissue protein bound pool, the highest enrichment levels were achieved in the kidney (11.7 MPE) and the lowest enrichment levels in the skeletal muscle tissue protein of the cow (between 1.5–2.4 MPE). The estimated protein synthesis rates of the various organ tissues should be regarded as underestimates, particularly for the organs with the higher turnover rates and high secretory activity, due to the lengthened (96 h) measurement period necessary for the production of the intrinsically labeled beef. Our data demonstrates that there are relatively small differences in L-[1-¹³C]phenylalanine enrichments between the various meat cuts, but substantial higher enrichment values are observed in the various organ tissues. We conclude that protein turnover rates of various organs are much higher when compared to skeletal muscle protein turnover rates in large lactating ruminants.     

Use of Root Organ Cultures To Investigate the Interaction between Glomus intraradices and Pratylenchus coffeae

The interaction between Glomus intraradices and Pratylenchus coffeae on transformed carrot roots was studied in root organ culture. G. intraradices provided the roots with increased protection against P. coffeae by suppressing nematode reproduction in the roots. The internal and external mycorrhizal development was not influenced by the presence of the nematodes.     

Developmental trends in mother-infant interactions in Java macaques (Macaca fascicularis) during the first ten days of life

In this study on Java macaques themain characteristics of the mother-infant relationship during infants' first 10 days have been elaborated. Early mother and infant behaviour is described and early interactions between mothers and their young have been analyzed. Observations and trend analyses of early behaviours like ventro-ventral contact behaviour, being on nipple, and explorative behaviour, make it clear that Java macaque infants play an important role in the early development of mother-infant interactions. In contrast to the rhesus and the stumptailed infant, the young Java macaque appears to develop a great variety of behaviours in its first 10 days. Whereas the infant's behaviour gains in complexity and social initiative, the mother becomes increasingly more passive and self-oriented. Early mother-infant interaction can be characterized by mutual adjustment.     

A Three-Dimensional Stereotaxic MRI Brain Atlas of the Cichlid Fish Oreochromis mossambicus

The African cichlid Oreochromis mossambicus (Mozambique tilapia) has been used as a model system in a wide range of behavioural and neurobiological studies. The increasing number of genetic tools available for this species, together with the emerging interest in its use for neurobiological studies, increased the need for an accurate hodological mapping of the tilapia brain to supplement the available histological data. The goal of our study was to elaborate a three-dimensional, high-resolution digital atlas using magnetic resonance imaging, supported by Nissl staining. Resulting images were viewed and analysed in all orientations (transverse, sagittal, and horizontal) and manually labelled to reveal structures in the olfactory bulb, telencephalon, diencephalon, optic tectum, and cerebellum. This high resolution tilapia brain atlas is expected to become a very useful tool for neuroscientists using this fish model and will certainly expand their use in future studies regarding the central nervous system.     

Neural correlates of behavioural olfactory sensitivity changes seasonally in European starlings

Background

Possibly due to the small size of the olfactory bulb (OB) as compared to rodents, it was generally believed that songbirds lack a well-developed sense of smell. This belief was recently revised by several studies showing that various bird species, including passerines, use olfaction in many respects of life. During courtship and nest building, male European starlings (Sturnus vulgaris) incorporate aromatic herbs that are rich in volatile compounds (e.g., milfoil, Achillea millefolium) into the nests and they use olfactory cues to identify these plants. Interestingly, European starlings show seasonal differences in their ability to respond to odour cues: odour sensitivity peaks during nest-building in the spring, but is almost non-existent during the non-breeding season.

Methodology/Principal Findings

This study used repeated in vivo Manganese-enhanced MRI to quantify for the first time possible seasonal changes in the anatomy and activity of the OB in starling brains. We demonstrated that the OB of the starling exhibits a functional seasonal plasticity of certain plant odour specificity and that the OB is only able to detect milfoil odour during the breeding season. Volumetric analysis showed that this seasonal change in activity is not linked to a change in OB volume. By subsequently experimentally elevating testosterone (T) in half of the males during the non-breeding season we showed that the OB volume was increased compared to controls.

Conclusions/Significance

By investigating the neural substrate of seasonal olfactory sensitivity changes we show that the starlings'' OB loses its ability during the non-breeding season to detect a natural odour of a plant preferred as green nest material by male starlings. We found that testosterone, applied during the non-breeding season, does not restore the discriminatory ability of the OB but has an influence on its size.     

Exercise training restores uncoupling protein-3 content in limb muscles of patients with chronic obstructive pulmonary disease

Oxidative capacity and uncoupling protein-3 (UCP3) content are reduced in limb muscles of patients with chronic obstructive pulmonary disease (COPD). It has been hypothesized that the physiological role of UCP3 is to protect mitochondria against lipotoxicity in cases where fatty acid influx exceeds the capacity to oxidize them. Exercise training improves oxidative capacity and reduces UCP3 protein content in healthy subjects, but the response of UCP3 to training in COPD is unknown. We studied the effect of exercise training on UCP3 content in limb muscles of COPD patients. For this, seven healthy age-matched subjects and thirteen patients with COPD were studied. All patients were admitted to an 8-wk exercise training intervention. Exercise capacity was assessed by means of an incremental cycle ergometry test. Biopsies were taken from the vastus lateralis in which UCP3 and lipid peroxidation levels were determined by Western blotting. Citrate synthase and 3-hydroxyacyl-CoA dehydrogenase (HAD; an enzyme involved in fatty acid oxidation) were measured as indexes of muscle oxidative capacity. UCP3 in COPD was approximately 50% lower compared with healthy age-matched controls. In COPD, training induced upregulation of UCP3 [from 67.7 (SD 41.8) to 113.8 (SD 104.2) arbitrary units (AU), P = 0.062], especially in the patients who showed no increase in HAD activity [from 80.9 (SD 52.6) to 167.9 (SD 109.1) AU, P = 0.028], whereas lipid peroxidation levels remained unaltered. We conclude that exercise-training can restore muscle UCP3 protein level in COPD, and the nature of this response complies with the hypothesis that UCP3 may protect against lipotoxicity.     

Distribution of the Mycobacterium community and polycyclic aromatic hydrocarbons (PAHs) among different size fractions of a long-term PAH-contaminated soil

Summary Mycobacterium is often isolated from polycyclic aromatic hydrocarbon (PAH)-contaminated soil as degraders of PAHs. In model systems, Mycobacterium shows attachment to the PAH substrate source, which is considered to be a particular adaptation to low bioavailability as it results into increased substrate flux to the degraders. To examine whether PAH-degrading Mycobacterium in real PAH-contaminated soils, in analogy with model systems, are preferentially associated with PAH-enriched soil particles, the distribution of PAHs, of the PAH-mineralizing capacity and of Mycobacterium over different fractions of a soil with an aged PAH contamination was investigated. The clay fraction contained the majority of the PAHs and showed immediate pyrene- and phenanthrene-mineralizing activity upon addition of (14)C-labelled pyrene or phenanthrene. In contrast, the sand and silt fractions showed a lag time of 15-26 h for phenanthrene and 3-6 days for pyrene mineralization. The maximum pyrene and phenanthrene mineralization rates of the clay fraction expressed per gram fraction were three to six times higher than those of the sand and silt fractions. Most-probable-number (MPN)-polymerase chain reaction demonstrated that Mycobacterium represented about 10% of the eubacteria in the clay fraction, while this was only about 0.1% in the sand and silt fractions, indicating accumulation of Mycobacterium in the PAH-enriched clay fraction. The Mycobacterium community composition in the clay fraction represented all dominant Mycobacterium populations of the bulk soil and included especially species related to Mycobacterium pyrenivorans, which was also recovered as one of the dominant species in the eubacterial communities of the bulk soil and the clay fraction. Moreover, Mycobacterium could be identified among the major culturable PAH-degrading populations in both the bulk soil and the clay fraction. The results demonstrate that PAH-degrading mycobacteria are mainly associated with the PAH-enriched clay fraction of the examined PAH-contaminated soil and hence, that also in the environmental setting of a PAH-contaminated soil, Mycobacterium might experience advantages connected to substrate source attachment.     

Helicobacter felis and Helicobacter bizzozeronii induce gastric parietal cell loss in Mongolian gerbils

Non-pylori helicobacter infections are associated with gastritis, gastric ulcers and MALT lymphomas in man. Approximately 50% of these are caused by helicobacters commonly found in dogs and cats, including Helicobacter felis, Helicobacter bizzozeronii and H. salomonis. In contrast to Helicobacter pylori, the virulence mechanisms of these species are unknown. In this study the virulence of H. felis, H. bizzozeronii and H. salomonis was investigated in Mongolian gerbils. Female SPF gerbils were inoculated intragastrically with H. felis, H. bizzozeronii or H. salomonis and sacrificed 3 weeks later. Fundus and antrum samples were taken for bacterial detection by PCR. A longitudinal strip covering all stomach regions was taken for histology. Gastric colonization, inflammation, apoptosis, loss of parietal cells and cell proliferation were assessed. Controls and H. salomonis inoculated gerbils were negative in PCR. H. felis and H. bizzozeronii inoculated animals were positive. H. felis inoculated animals showed loss of parietal cells extending from the limiting ridge into the fundus. A high cell proliferation rate was noticed in the mucosal area devoid of parietal cells. A dense band of apoptotic cells and large numbers of Helicobacter bacteria were seen at the transition zone between affected and normal parietal cells. In H. bizzozeronii infected gerbils, this was less pronounced. Focal apoptotic loss of gastric epithelial cells was spatially associated with the presence of bacteria especially in H. felis and to a lesser extent in H. bizzozeronii infected gerbils. This loss of cells may lead to intestinal metaplasia.