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71.
Population connectivity is driven by individual dispersal potential and modulated by natal philopatry. In seabirds, high vagility facilitates dispersal yet philopatry is also common, with foraging area overlap often correlated with population connectivity. We assess the interplay between these processes by studying past and current connectivity and foraging niche overlap among southern rockhopper penguin colonies of the coast of southern South America using genomic and stable isotope analyses. We found two distinct genetic clusters and detected low admixture between northern and southern colonies. Stable isotope analysis indicated niche variability between colonies, with Malvinas/Falklands colonies encompassing the species entire isotopic foraging niche, while the remaining colonies had smaller, nonoverlapping niches. A recently founded colony in continental Patagonia differed in isotopic niche width and position with Malvinas/Falklands colonies, its genetically identified founder population, suggesting the exploitation of novel foraging areas and/or prey items. Additionally, dispersing individuals found dead across the Patagonian shore in an unusual mortality event were also assigned to the northern cluster, suggesting northern individuals reach southern localities, but do not breed in these colonies. Facilitated by variability in foraging strategies, and especially during unfavorable conditions, the number of dispersing individuals may increase and enhance the probability of founding new colonies. Metapopulation demographic dynamics in seabirds should account for interannual variability in dispersal behavior and pay special attention to extreme climatic events, classically related to negative effects on population trends.  相似文献   
72.
In revegetation projects, distinguishing species that can be passively restored by natural regeneration from those requiring active restoration is not a trivial decision. We quantified tree species dominance (measured by an importance value index, IVIi) and used abundance–size correlations to select those species suitable for passive and/or active restoration of disturbed riparian vegetation in the Lacandonia region, Southern Mexico. We sampled riparian vegetation in a 50 × 10–m transect in each of six reference (RE) and five disturbed (DE) riparian ecosystems. Those species representing more than 50% of total IVI in each ecosystem were selected, and Spearman rank correlation between abundance and diameter classes was calculated. For eight species, it was determined that passive restoration could be sufficient for their establishment. Another eight species could be transplanted by means of active restoration. Five species regenerate well in only one ecosystem type, suggesting that both restoration strategies could be used depending on the degree of degradation. Finally, two species were determined to not be suitable for restoration in the RE (based on the above selection criteria) and were not selected during this initial stage of our restoration project. The high number of tree species found in the RE suggests that the species pool for ecological restoration is large. However, sampling in both ecosystem types helped us reduce the number of species that requires active restoration. Restoration objectives must guide the selection of which methods to implement; in different conditions, other criteria such as dispersal syndrome or social value could be considered in the species selection.  相似文献   
73.
The context of this paper is the development of a general and efficient numerical haemodynamic tool to help clinicians and researchers in understanding of physiological flow phenomena. We propose an accurate one-dimensional Runge–Kutta discontinuous Galerkin (RK-DG) method coupled with lumped parameter models for the boundary conditions. The suggested model has already been successfully applied to haemodynamics in arteries and is now extended for the flow in collapsible tubes such as veins. The main difference with cardiovascular simulations is that the flow may become supercritical and elastic jumps may appear with the numerical consequence that scheme may not remain monotone if no limiting procedure is introduced. We show that our second-order RK-DG method equipped with an approximate Roe's Riemann solver and a slope-limiting procedure allows us to capture elastic jumps accurately. Moreover, this paper demonstrates that the complex physics associated with such flows is more accurately modelled than with traditional methods such as finite difference methods or finite volumes. We present various benchmark problems that show the flexibility and applicability of the numerical method. Our solutions are compared with analytical solutions when they are available and with solutions obtained using other numerical methods. Finally, to illustrate the clinical interest, we study the emptying process in a calf vein squeezed by contracting skeletal muscle in a normal and pathological subject. We compare our results with experimental simulations and discuss the sensitivity to parameters of our model.  相似文献   
74.
75.
HeLa cell line stably transfected with the tat gene from human immunodeficiency virus type 1 has a decreased antioxidant potential. In this work, we used this model to investigate the effect of a high glucose level (20 mM) on the glucose induced cytotoxicity and on the antioxidant system. In comparison to cell culture under control medium, HeLa-wild cell cultured under 20 mM glucose did not exhibit necrosis or apoptosis, contrary to HeLa-tat cell presenting a significant increase in necrotic or apoptotic state. Moreover after 48 h culture under high glucose level the HeLa-tat proliferation rate was not higher than the one of HeLa-wild cells. In HeLa-wild cell high glucose level resulted in an induction of glutathione reductase activity in opposition to HeLa-tat cells where no change was observed. High glucose level resulted in 20% increase in GSSG/GSH ratio in HeLa-wild cells and 38% increase in HeLa-tat cells. Moreover, high glucose level resulted in a dramatic cytosolic thiol decrease and an important lipid peroxidation in HeLa-tat cells. No significant change of these two parameters was observed in HeLa-wild cells. In both cell lines, high glucose resulted in an increase of total SOD activity, as a consequence of the increase in Cu,Zn-SOD activity. High glucose did not result in an increase of Mn-SOD activity in both cell lines. As a consequence of tat tranfection Mn-SOD activity was 50% lower in HeLa-tat cells in comparison to HeLa-wild cells. This work emphasizes the importance of the antioxidant system in the glucose induced cytotoxicity.  相似文献   
76.
A new family of antimicrotubule drugs named (3-haloacetamidobenzoyl) ureas and ethyl 3-haloacetamidobenzoates were found to be cytotoxic to the Leishmania parasite protozoa. While the benzoylureas were shown to strongly inhibit in vitro mammalian brain microtubule assembly, the ethyl ester derivatives were characterized as very poor inhibitors of this process. Ethyl 3-chloroacetamidobenzoate, MF29, was found to be the most efficient drug on the promastigote stage of three Leishmania species (IC50: 0.3–1.8 μM). MF29 maintained its activity against the clinical relevant intracellular stage of L. mexicana with IC50 value of 0.33 μM. It was the only compound that exhibits a high activity on all the Leishmania species tested. This compound appeared to alter parasite microtubule organisation as demonstrated by using antibodies directed against microtubule components and more precisely the class of microtubule decorated by the MAP2-like protein. It is interesting to notice that this MAP2-like protein was identified for the first time in a Leishmania parasite  相似文献   
77.
Abstract

(E) 5-Alkenyl 2′-deoxyuridines were synthesized with moderate to high yields by the palladium catalyzed coupling of alkenyl-zirconium reagents with 0–3′, 5′-his (trimethylsilyl) deoxyuridine in T H F. Some of these 5-alkenyl-dUrd analogues, i.e. the 1-decenyl (5g) and 2- (1-hydroxycyclopentyl) ethenyl (5f) derivatives, inhibited murine L1210 cell growth at a concentration of about 4 μg/ml, whereas the 5-chloro-1-pentenyl (5c), 5-cyano-1-pentenyl (5d), 5-hexyn-1-enyl (5e) and 2-(1-hydroxycyclopentyl) ethenyl (5f) were inhibitory towards herpes simplex and vaccinia virus within the concentration range of 2–60 μg/ml. However, none of the newly synthesized 5-alkenyl-dUrd analogues proved selective in its antiviral action.  相似文献   
78.
Certain conditions, such as several weeks of high-fat diet, disrupt endoplasmic reticulum (ER) homeostasis and activate an adaptive pathway referred as the unfolded protein response. When the unfolded protein response fails, the result is the development of inflammation and insulin resistance. These two pathological states are known to be improved by regular exercise training but the mechanisms remain largely undetermined. As it has recently been shown that the unfolded protein response is regulated by exercise, we hypothesised that concomitant treadmill exercise training (HFD+ex) prevents ER homeostasis disruption and its downstream consequences induced by a 6-week high-fat diet (HFD) in mice by activating the protective unfolded protein response. Several well-documented markers of the unfolded protein response were measured in the soleus and tibialis anterior muscles as well as in the liver and pancreas. In HFD mice, an increase in these markers was observed (from 2- to 15-fold, P?<?0.05) in all tissues studied. The combination of HFD+ex increased the expression of several markers further, up to 100 % compared to HFD alone (P?<?0.05). HFD increased inflammatory markers both in the plasma (IL-6 protein, 2.5?±?0.52-fold; MIP-1α protein, 1.3?±?0.13-fold; P?<?0.05) and in the tissues studied, and treadmill exercise attenuated the inflammatory state induced by HFD (P?<?0.05). However, treadmill exercise could not reverse HFD-induced whole body glucose intolerance, assessed by OGTT (AUC, 1.8?±?0.29-fold, P?<?0.05). In conclusion, our results show that a HFD activated the unfolded protein response in mouse tissues in vivo, and that endurance training promoted this response. We speculate that the potentiation of the unfolded protein response by endurance training may represent a positive adaptation protecting against further cellular stress.  相似文献   
79.
All genus-group names listed in the second edition of the catalogue (1833-1836) of Dejean’s beetle collection are recorded. For each new genus-group name the originally included available species are listed and for generic names with at least one available species, the type species and the current status are given. Names available prior to the publication of Dejean’s second catalogue (1833-1836) are listed in an appendix.The following new synonymies are proposed: Cyclonotum Dejean, 1833 (= Dactylosternum Wollaston, 1854) [Hydrophilidae], Hyporhiza Dejean, 1833 (= Rhinaspis Perty, 1830) [Scarabaeidae], Aethales Dejean, 1834 (= Epitragus Latreille, 1802) [Tenebrionidae], Arctylus Dejean, 1834 (= Praocis Eschscholtz, 1829) [Tenebrionidae], Euphron Dejean, 1834 (= Derosphaerus Thomson, 1858) [Tenebrionidae], Hipomelus Dejean, 1834 (= Trachynotus Latreille, 1828) [Tenebrionidae], Pezodontus Dejean, 1834 (= Odontopezus Alluaud, 1889) [Tenebrionidae], Zygocera Dejean, 1835 (= Disternopsis Breuning, 1939) [Cerambycidae], and Physonota Chevrolat, 1836 (= Anacassis Spaeth, 1913) [Chrysomelidae]. Heterogaster pilicornis Dejean, 1835 [Cerambycidae] and Labidomera trimaculata Chevrolat, 1836 [Chrysomelidae] are placed for the first time in synonymy with Anisogaster flavicans Deyrolle, 1862 and Chrysomela clivicollis Kirby, 1837 respectively. Type species of the following genus-group taxa are proposed: Sphaeromorphus Dejean, 1833 (Sphaeromorphus humeralis Erichson, 1843) [Scarabaeidae], Adelphus Dejean, 1834 (Helops marginatus Fabricius, 1792) [Tenebrionidae], Cyrtoderes Dejean, 1834 (Tenebrio cristatus DeGeer, 1778) [Tenebrionidae], Selenepistoma Dejean, 1834 (Opatrum acutum Wiedemann, 1823) [Tenebrionidae], Charactus Dejean, 1833 (Lycus limbatus Fabricius, 1801) [Lycidae], Corynomalus Chevrolat, 1836 (Eumorphus limbatus Olivier, 1808) [Endomychidae], Hebecerus Dejean, 1835 (Acanthocinus marginicollis Boisduval, 1835) [Cerambycidae], Pterostenus Dejean, 1835 (Cerambyx abbreviatus Fabricius, 1801) [Cerambycidae], Psalicerus Dejean, 1833 (Lucanus femoratus Fabricius, 1775) [Lucanidae], and Pygolampis Dejean, 1833 (Lampyris glauca Olivier, 1790) [Lampyridae]. A new name, Neoeutrapela Bousquet and Bouchard [Tenebrionidae], is proposed for Eutrapela Dejean, 1834 (junior homonym of Eutrapela Hübner, 1809).The following generic names, made available in Dejean’s catalogue, were found to be older than currently accepted valid names: Catoxantha Dejean, 1833 over Catoxantha Solier, 1833 [Buprestidae], Pristiptera Dejean, 1833 over Pelecopselaphus Solier, 1833 [Buprestidae], Charactus Dejean, 1833 over Calopteron Laporte, 1836 [Lycidae], Cyclonotum Dejean, 1833 over Dactylosternum Wollaston, 1854 [Hydrophilidae], Ancylonycha Dejean, 1833 over Holotrichia Hope, 1837 [Scarabaeidae], Aulacium Dejean, 1833 over Mentophilus Laporte, 1840 [Scarabaeidae], Sciuropus Dejean, 1833 over Ancistrosoma Curtis, 1835 [Scarabaeidae], Sphaeromorphus Dejean, 1833 over Ceratocanthus White, 1842 [Scarabaeidae], Psalicerus Dejean, 1833 over Leptinopterus Hope, 1838 [Lucanidae], Adelphus Dejean, 1834 over Praeugena Laporte, 1840 [Tenebrionidae], Amatodes Dejean, 1834 over Oncosoma Westwood, 1843 [Tenebrionidae], Cyrtoderes Dejean, 1834 over Phligra Laporte, 1840 [Tenebrionidae], Euphron Dejean, 1834 over Derosphaerus Thomson, 1858 [Tenebrionidae], Pezodontus Dejean, 1834 over Odontopezus Alluaud, 1889 [Tenebrionidae], Anoplosthaeta Dejean, 1835 over Prosopocera Blanchard, 1845 [Cerambycidae], Closteromerus Dejean, 1835 over Hylomela Gahan, 1904 [Cerambycidae], Hebecerus Dejean, 1835 over Ancita Thomson, 1864 [Cerambycidae], Mastigocera Dejean, 1835over Mallonia Thomson, 1857 [Cerambycidae], Zygocera Dejean, 1835 over Disternopsis Breuning, 1939 [Cerambycidae], Australica Chevrolat, 1836 over Calomela Hope, 1840 [Chrysomelidae], Edusa Chevrolat, 1836 over Edusella Chapuis, 1874 [Chrysomelidae], Litosonycha Chevrolat, 1836 over Asphaera Duponchel and Chevrolat, 1842 [Chrysomelidae], and Pleuraulaca Chevrolat, 1836 over Iphimeis Baly, 1864 [Chrysomelidae]. In each of these cases, Reversal of Precedence (ICZN 1999: 23.9) or an applicationto the International Commission on Zoological Nomenclature will be necessary to retain usage of the younger synonyms.  相似文献   
80.
Respiratory syncytial virus (RSV) is a high priority target for vaccine development. One concern in RSV vaccine development is that a non-live virus vaccine would predispose for enhanced disease similar to that seen with the formalin inactivated RSV (FI-RSV) vaccine. Since a mAb specific to RSV G protein can reduce pulmonary inflammation and eosinophilia seen after RSV infection of FI-RSV vaccinated mice, we hypothesized that RSV G peptides that induce antibodies with similar reactivity may limit enhanced disease after subunit or other non-live RSV vaccines. In support of this hypothesis, we show that FI-RSV vaccinated mice administered RSV G peptide vaccines had a significant reduction in enhanced disease after RSV challenge. These data support the importance of RSV G during infection to RSV disease pathogenesis and suggest that use of appropriately designed G peptide vaccines to reduce the risk of enhanced disease with non-live RSV vaccines merits further study.  相似文献   
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