Changes in the global electromyogram during static exercise; effect of age

In normal man, the EMG changes in forearm muscles holding a tension of 30% maximal voluntary strength for 5 minutes are: (1) an increase of integrated EMG, (2) a slight decrease of the median frequency of the EMG power spectrum. These changes are largely reduced with age.     

The glycoprotein GP130 governs the surface presentation of the G protein–coupled receptor APLNR

Glioblastoma is one of the most lethal forms of adult cancer, with a median survival of ∼15 mo. Targeting glioblastoma stem-like cells (GSCs) at the origin of tumor formation and relapse may prove beneficial. In situ, GSCs are nested within the vascular bed in tight interaction with brain endothelial cells, which positively control their expansion. Because GSCs are notably addicted to apelin (APLN), sourced from the surrounding endothelial stroma, the APLN/APLNR nexus has emerged as a druggable network. However, how this signaling axis operates in gliomagenesis remains underestimated. Here, we find that the glycoprotein GP130 interacts with APLNR at the plasma membrane of GSCs and arbitrates its availability at the surface via ELMOD1, which may further impact on ARF-mediated endovesicular trafficking. From a functional standpoint, interfering with GP130 thwarts APLNR-mediated self-renewal of GSCs ex vivo. Thus, GP130 emerges as an unexpected cicerone to the G protein–coupled APLN receptor, opening new therapeutic perspectives toward the targeting of cancer stem cells.     

<Emphasis Type="Italic">Rhipicephalus</Emphasis> (<Emphasis Type="Italic">Boophilus</Emphasis>) <Emphasis Type="Italic">microplus</Emphasis>: a most successful invasive tick species in West-Africa

The cattle tick Rhipicephalus (Boophilus) microplus is known to be a highly reproductive and efficient vector of Babesia bovis, two characters which make this tick a threat to livestock keeping in many continents. The authors identified this tick in Ivory Coast, West Africa, in 2007, and hypothesized the spread to be minimal, as this tick was not observed in previous years. To determine the extent of its distribution and to a lesser extent the possible impact of the tick on the livelihoods of Ivorian smallholders, a cross-sectional survey was carried out in the Abidjan and Agboville Departments of Ivory Coast, in April 2008. The results of the study reveal that the newly introduced tick has almost completely displaced all indigenous Rhipicephalus (Boophilus) species in the study area and gave rise to unsuccessful tick control, inappropriate pesticide use, loss of milk production and even increased mortality in dairy cattle.     

New Archaeozoological Data from the Fayum “Neolithic” with a Critical Assessment of the Evidence for Early Stock Keeping in Egypt

Faunal evidence from the Fayum Neolithic is often cited in the framework of early stock keeping in Egypt. However, the data suffer from a number of problems. In the present paper, large faunal datasets from new excavations at Kom K and Kom W (4850–4250 BC) are presented. They clearly show that, despite the presence of domesticates, fish predominate in the animal bone assemblages. In this sense, there is continuity with the earlier Holocene occupation from the Fayum, starting ca. 7350 BC. Domesticated plants and animals appear first from approximately 5400 BC. The earliest possible evidence for domesticates in Egypt are the very controversial domesticated cattle from the 9^th/8^th millennium BC in the Nabta Playa-Bir Kiseiba area. The earliest domesticates found elsewhere in Egypt date to the 6^th millennium BC. The numbers of bones are generally extremely low at this point in time and only caprines are present. From the 5^th millennium BC, the numbers of sites with domesticates dramatically increase, more species are also involved and they are usually represented by significant quantities of bones. The data from the Fayum reflect this two phase development, with very limited evidence for domesticates in the 6^th millennium BC and more abundant and clearer indications in the 5^th millennium BC. Any modelling of early food production in Egypt suffers from poor amounts of data, bias due to differential preservation and visibility of sites and archaeological remains, and a lack of direct dates for domesticates. In general, however, the evidence for early stock keeping and accompanying archaeological features shows large regional variation and seems to be mainly dependent on local environmental conditions. The large numbers of fish at Kom K and Kom W reflect the proximity of Lake Qarun.     

Neurotensin receptor 1 is expressed in gastrointestinal stromal tumors but not in interstitial cells of Cajal

Gastrointestinal stromal tumors (GIST) are thought to derive from the interstitial cells of Cajal (ICC) or an ICC precursor. Oncogenic mutations of the KIT or PDGFRA receptor tyrosine kinases are present in the majority of GIST, leading to ligand-independent activation of the intracellular signal transduction pathways. We previously investigated the gene expression profile in the murine Kit(K641E) GIST model and identified Ntsr1 mRNA, encoding the Neurotensin receptor 1, amongst the upregulated genes. Here we characterized Ntsr1 mRNA and protein expression in the murine Kit(K641E) GIST model and in tissue microarrays of human GIST. Ntsr1 mRNA upregulation in Kit(K641E) animals was confirmed by quantitative PCR. Ntsr1 immunoreactivity was not detected in the Kit positive ICC of WT mice, but was present in the Kit positive hyperplasia of Kit(K641E) mice. In the normal human gut, NTSR1 immunoreactivity was detected in myenteric neurons but not in KIT positive ICC. Two independent tissue microarrays, including a total of 97 GIST, revealed NTSR1 immunoreactivity in all specimens, including the KIT negative GIST with PDGFRA mutation. NTSR1 immunoreactivity exhibited nuclear, cytoplasmic or mixed patterns, which might relate to variable levels of NTSR1 activation. As studies using radio-labeled NTSR1 ligand analogues for whole body tumor imaging and for targeted therapeutic interventions have already been reported, this study opens new perspectives for similar approaches in GIST.     

Transportin-SR2 imports HIV into the nucleus

BACKGROUND: The human immunodeficiency virus type 1 (HIV-1) and other lentiviruses have the capacity to infect nondividing cells like macrophages. This requires import of the preintegration complex (PIC) through the nuclear pore. Although many cellular and viral determinants have been proposed, the mechanism leading to nuclear import is not yet understood. RESULTS: Using yeast two-hybrid and pull-down, we identified and validated transportin-SR2 (TRN-SR2) as a bona fide binding partner of HIV-1 integrase. We confirmed the biological relevance of this interaction by RNAi. Depletion of TRN-SR2 interfered with the replication of HIV-1 and HIV-2 but not MoMLV in HeLaP4 cells. Knockdown of TRN-SR2 in primary macrophages likewise interfered with HIV-1 replication. Using Q-PCR, we pinpoint this block in replication to the early steps of the viral lifecycle. A reduction in 2-LTR formation suggests a block in PIC nuclear import upon siRNA-mediated knockdown. Different lines of evidence clearly proved that the late steps of viral replication are not affected. In an in vivo nuclear-import assay using labeled HIV-1 particles, the defect in nuclear import after depletion of TRN-SR2 was directly visualized. In comparison with control cell lines, the great majority of siRNA-treated cells did not contain any PIC in the nucleus. CONCLUSION: Our data clearly demonstrate that TRN-SR2 is the nuclear-import factor of HIV.     

Grazing experiments with two freshwater zooplankters:fate of chlorophyll and carotenoid pigments

In order to evaluate the validity of the gut pigment methodto assess grazing and diet in two freshwater zooplankters, experimentswere carried out to check chlorophyll a and xanthophyll conservationduring feeding. For both animals, two sets of experiments wereconducted by incubating animals in the laboratory, either isolatedfrom a reservoir (the calanoid copepod, Eudiaptomus gracilis)or cultured under high-food conditions (the cladoceran, Daphniagaleata). For both animals, gut pigments and clearance rateson different types of algae were determined from the same incubations.Chlorophyll a and derivatives, as well as major algal carotenoids,were analysed by High Performance Liquid Chromatography (HPLC).In copepods, the pigment profiles from the gut extracts reflectedthe diet of the animals poorly. The animal extracts containedalmost exclusively alloxanthin (or an alloxanthin-like pigment)in large amounts, whereas the other pigments were lost in highproportions (>70% for lutein and fucoxanthin; 57 and 78%for a-phorbins). The cladocerans fed on the main types of algaeabundant in the suspensions, with a preference, however, forsmall cells. Although the main xanthophylls from these algaewere detected in the Daphnia extracts, some destruction of luteinand fucoxanthin may have occurred (18.7 and 30%). The loss ratefor alloxanthin seemed more variable (0 and 68%), possibly dependingon food concentration. As for the transformation of a-phorbins,E.gracilis and D.galeata behaved quite differently. The HPLCprofiles of copepod extracts always showed a very small chlorophylla peak, along with phaeophytin a and pyrophaeophytin a. Thosefrom the cladoceran exhibited a large phaeophorbide a peak,along with some chlorophyll a and phaeophytin a. In fact, D.galeatadid not destroy a-phorbins under our experimental conditionsbut converted chlorophyll a mainly into phaeophorbide. Froma comparison of our results with data from other studies, itseems that in these two zooplankters, use of gut pigment datafor quantitative grazing assessment should be considered withcaution.     

Improving physical activity in COPD: towards a new paradigm

Chronic obstructive pulmonary disease (COPD) is a debilitating disease affecting patients in daily life, both physically and emotionally. Symptoms such as dyspnea and muscle fatigue, lead to exercise intolerance, which, together with behavioral issues, trigger physical inactivity, a key feature of COPD. Physical inactivity is associated with adverse clinical outcomes, including hospitalization and all-cause mortality. Increasing activity levels is crucial for effective management strategies and could lead to improved long-term outcomes. In this review we summarize objective and subjective instruments for evaluating physical activity and focus on interventions such as pulmonary rehabilitation or bronchodilators aimed at increasing activity levels. To date, only limited evidence exists to support the effectiveness of these interventions. We suggest that a multimodal approach comprising pulmonary rehabilitation, pharmacotherapy, and counselling programs aimed at addressing emotional and behavioural aspects of COPD may be an effective way to increase physical activity and improve health status in the long term.