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141.
Disturbances to monitors and baits have often been noted as a confounding factor for the success of termite baiting systems.
We studied escape behavior of Coptotermes formosanus Shiraki to a food source disturbance in the laboratory. Four peripheral chambers connected to the central food chamber through
tubes served as escape routes from which escape patterns, escape and return times and differences in soldier and worker responses
were recorded. We used two sand conditions: moist and dry to test whether favorable versus unfavorable conditions change escape
behavior. The post disturbance responses were video recorded for 1 h. C. formosanus quickly escaped from the central chamber when disturbed. The time taken to reach the maximum number of termites that escaped
ranged from 20 s to 210 s followed by a gradual return to the disturbed chamber. The majority of the escapees returned to
the disturbed area within a few minutes after evacuation in both dry and wet sand conditions. A significantly higher percentage
of termites escaped in wet sand arenas (43%) than in the dry sand arenas (31%). Our experiments demonstrate that C. formosanus is highly unlikely to abandon bait stations for extensive periods of time as a result of mechanical disturbances regardless
of habitat quality. 相似文献
142.
Hoijman E Rocha-Viegas L Kalko SG Rubinstein N Morales-Ruiz M Joffé EB Kordon EC Pecci A 《Journal of cellular physiology》2012,227(4):1721-1730
Glucocorticoids influence post-natal mammary gland development by sequentially controlling cell proliferation, differentiation, and apoptosis. In the mammary gland, it has been demonstrated that glucocorticoid treatment inhibits epithelial apoptosis in post-lactating glands. In this study, our first goal was to identify new glucocorticoid target genes that could be involved in generating this effect. Expression profiling, by microarray analysis, revealed that expression of several cell-cycle control genes was altered by dexamethasone (DEX) treatment after lactation. Importantly, it was determined that not only the exogenous synthetic hormone, but also the endogenous glucocorticoids regulated the expression of these genes. Particularly, we found that the expression of cell cycle inhibitors p21CIP1, p18INK4c, and Atm was differentially regulated by glucocorticoids through the successive stages of mammary gland development. In undifferentiated cells, DEX treatment induced their expression and reduced cell proliferation, while in differentiated cells this hormone repressed expression of those cell cycle inhibitors and promoted survival. Therefore, differentiation status determined the effect of glucocorticoids on mammary cell fate. Particularly, we have determined that p21CIP1 inhibition would mediate the activity of these hormones in differentiated mammary cells because over-expression of this protein blocked DEX-induced apoptosis protection. Together, our data suggest that the multiple roles played by glucocorticoids in mammary gland development and function might be at least partially due to the alternative roles that these hormones play on the expression of cell cycle regulators. 相似文献
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145.
Hegedüs C Truta-Feles K Antalffy G Brózik A Kasza I Német K Orbán TI Özvegy-Laczka C Váradi A Sarkadi B 《Biochemical and biophysical research communications》2012,420(4):869-874
The ATP-binding cassette (ABC) transporter ABCG2 plays an important role in tissue detoxification and confers multidrug resistance to cancer cells. Identification of expressional and functional cellular regulators of this multidrug transporter is therefore intensively pursued. The PI3-kinase/Akt signaling axis has been implicated as a key element in regulating various cellular functions, including the expression and plasma membrane localization of ABCG2. Here we demonstrate that besides inhibiting their respective target kinases, the pharmacological PI3-kinase inhibitor LY294002 and the downstream mTOR kinase inhibitor rapamycin also directly inhibit ABCG2 function. In contrast, wortmannin, another commonly used pharmacological inhibitor of PI3-kinase does not interact with the transporter. We suggest that direct functional modulation of ABCG2 should be taken into consideration when pharmacological agents are applied to dissect the specific role of PI3-kinase/Akt/mTOR signaling in cellular functions. 相似文献
146.
Shenoy GN Chatterjee P Kaw S Mukherjee S Rathore DK Bal V Rath S George A 《Journal of immunology (Baltimore, Md. : 1950)》2012,189(2):521-528
Successful recall Ab responses require recruitment of quiescent memory B cells to secondary lymphoid organs. However, the cellular dynamics of memory cells responding to local antigenic challenge at lymphoid sites distal from the initial Ag encounter are not well understood. We show in this study that memory B cells generated following s.c. immunization in one footpad generate secondary responses to soluble Ag given i.p. but not to Ag given s.c. in the contralateral footpad unless LPS is coadministered. Memory B cells do not express CD62L, and CD62L(-ve) cells cannot enter lymph nodes unless LPS-mediated inflammation is induced there. Functional TLR4 is required on the B cells, as well as on non-B cells, in the lymph node to achieve full recruitment. Furthermore, splenectomized mice fail to respond to such inflammatory s.c. challenge in contralateral footpads, unlike lymphadenectomized mice lacking the original draining lymph nodes. Splenectomized mice also fail to respond to i.p. challenge with soluble Ag. Together, these data indicate that, unlike the central memory pool of T cells, which circulates through resting lymph nodes, the majority of long-lived memory B cells are spleen resident and require inflammatory signals for mounting recall responses at distal challenge sites. 相似文献
147.
Tiago Siebert Altavini Leonardo Dutra Henriques Daniela Maria Oliveira Bonci Balázs Vince Nagy Dora Fix Ventura Valdir Filgueiras Pessoa 《International journal of primatology》2012,33(6):1467-1476
The identification of color vision types in primates is fundamental to understanding the evolution and biological function of color perception. The Hard, Randy, and Rittler (HRR) pseudoisochromatic test categorizes human color vision types successfully. Here we provide an experimental setup to employ HRR in a nonhuman primate, the capuchin (Cebus libidinosus), a platyrrhine with polymorphic color vision. The HRR test consists of plates with a matrix composed of gray circles that vary in size and brightness. Differently colored circles form a geometric shape (X, O, or Δ) that is discriminated visually from the gray background pattern. The ability to identify these shapes determines the type of dyschromatopsy (deficiency in color vision). We tested six capuchins in their own cages under natural sunlight. The subjects chose between two HRR plates in each trial: one with the gray pattern only and the other with a colored shape, presented on the left or right side at random. We presented the test 40 times and calculated the 95?% confidence limits for chance performance based on the binomial test. We also genotyped all subjects for exons 3 and 5 of the X-linked opsin genes. The HRR test diagnosed two subjects as protan dichromats (missing or defective L-cone), three as deutan dichromats (missing or defective M-cone), and one female as trichromat. Genetic analysis supported the behavioral data for all subjects. These findings show that the HRR test can be applied to diagnose color vision in nonhuman primates. 相似文献
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149.
S Karampuri P Bag S Yasmin DK Chouhan C Bal D Mitra D Chattopadhyay A Sharon 《Bioorganic & medicinal chemistry letters》2012,22(19):6261-6266
Several options for treating Herpes Simplex Virus type 1 and type 2 are available. However, non-specific inhibition and drug resistance warrants the discovery of new anti-herpetic compounds with better therapeutic profile or different mode of action. The non-nucleoside inhibitors of HSV DNA polymerase target the site that is less important for the binding of a natural nucleoside or nucleoside inhibitors. In the present study, we have explored the possibility to find a new lead molecule based on α-pyrone analogs as non-nucleoside inhibitors using structure based modeling approach. The designed molecules were synthesized and evaluated for anti-HSV activity using MTT assay. The compound 5h with EC(50) 7.4μg/ml and CC(50) 52.5μg/ml was moderately active against HSV when compared to acyclovir. A plaque reduction assay was also carried out and results reveal that 5h is more effective against HSV-1 with better selective index of 12.8 than against HSV-2 (SI=3.6). The synthesized compounds were also evaluated for anti-HIV activity, but none were active. 相似文献
150.
Daniel Gruľa Mária Balážová Gordon H. Copp Vladimír Kováč 《Central European Journal of Biology》2012,7(3):448-459
Age and growth of the invasive population of round goby Neogobius melanostomus from the Slovak stretch of River Danube was examined. The samples (n=1130) were collected soon after the invasion was recorded
(2004–2005), and later, when the population was already established (2008–2010). Invasive round goby in newly-occupied areas
were found to reach smaller body size (15–153 mm standard length) compared to native populations. Age from 0+ to 4+, determined
from scales, was recorded in both sexes. Annulus formed in April–May, which varied with age. Growth of freshly established
gobies was negative allometric, suggesting increased allocation of their sources to reproduction, which corresponds to less
specialized life-history. However, positive allometric growth found in longer established individuals suggests a shift in
allocation towards somatic growth, which corresponds to more specialized life-history typical for native populations. None
of the three parameters predicted by the theory of alternative ontogenies and invasive potential met the expectations, though
two parameters, i.e. growth rate and age at maturation remain equivocal. This can be explained by too short of a time span that has elapsed from
the beginning of invasion, or by ecological disturbances that have broken up otherwise stable environment in the habitat studied. 相似文献