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51.
Kanakadurga Singer David L. Morris Kelsie E. Oatmen Tianyi Wang Jennifer DelProposto Taleen Mergian Kae Won Cho Carey N. Lumeng 《PloS one》2013,8(3)
Neuropeptide Y (NPY) is induced in peripheral tissues such as adipose tissue with obesity. The mechanism and function of NPY induction in fat are unclear. Given the evidence that NPY can modulate inflammation, we examined the hypothesis that NPY regulates the function of adipose tissue macrophages (ATMs) in response to dietary obesity in mice. NPY was induced by dietary obesity in the stromal vascular cells of visceral fat depots from mice. Surprisingly, the induction of Npy was limited to purified ATMs from obese mice. Significant basal production of NPY was observed in cultured bone marrow derived macrophage and dendritic cells (DCs) and was increased with LPS stimulation. In vitro, addition of NPY to myeloid cells had minimal effects on their activation profiles. NPY receptor inhibition promoted DC maturation and the production of IL-6 and TNFα suggesting an anti-inflammatory function for NPY signaling in DCs. Consistent with this, NPY injection into lean mice decreased the quantity of M1-like CD11c+ ATMs and suppressed Ly6chi monocytes. BM chimeras generated from Npy−/− donors demonstrated that hematopoietic NPY contributes to the obesity-induced induction of Npy in fat. In addition, loss of Npy expression from hematopoietic cells led to an increase in CD11c+ ATMs in visceral fat with high fat diet feeding. Overall, our studies suggest that NPY is produced by a range of myeloid cells and that obesity activates the production of NPY in adipose tissue macrophages with autocrine and paracrine effects. 相似文献
52.
Kaposi''s sarcoma-associated herpesvirus (KSHV) latency-associated nuclear antigen (LANA) is a 1,162-amino-acid protein that mediates the maintenance of episomal viral genomes in latently infected cells. The two central components of episome persistence are DNA replication with each cell division and the segregation of DNA to progeny nuclei. LANA self-associates to bind KSHV terminal-repeat (TR) DNA and to mediate its replication. LANA also simultaneously binds to TR DNA and mitotic chromosomes to mediate the segregation of episomes to daughter nuclei. The N-terminal region of LANA binds histones H2A and H2B to attach to mitotic chromosomes, while the C-terminal region binds TR DNA and also associates with chromosomes. Both the N- and C-terminal regions of LANA are essential for episome persistence. We recently showed that deletion of all internal LANA sequences results in highly deficient episome maintenance. Here we assess independent internal LANA regions for effects on episome persistence. We generated a panel of LANA mutants that included deletions in the large internal repeat region and in the unique internal sequence. All mutants contained the essential N- and C-terminal regions, and as expected, all maintained the ability to associate with mitotic chromosomes in a wild-type fashion and to bind TR DNA, as assessed by electrophoretic mobility shift assays (EMSA). Deletion of the internal regions did not reduce the half-life of LANA. Notably, deletions within either the repeat elements or the unique sequence resulted in deficiencies in DNA replication. However, only the unique internal sequence exerted effects on the ability of LANA to retain green fluorescent protein (GFP) expression from TR-containing episomes deficient in DNA replication, consistent with a role in episome segregation; this region did not independently associate with mitotic chromosomes. All mutants were deficient in episome persistence, and the deficiencies ranged from minor to severe. Mutants deficient in DNA replication that contained deletions within the unique internal sequence had the most-severe deficits. These data suggest that internal LANA regions exert critical roles in LANA-mediated DNA replication, segregation, and episome persistence, likely through interactions with key host cell factors. 相似文献
53.
James F. Harwood Roger I. Vargas James R. Carey 《Entomologia Experimentalis et Applicata》2013,147(1):73-81
Injuries frequently accumulate with age in nature. Despite the commonality of injury and the resulting impairment, there are limited experimental data for the effects of impairment on life history trade‐offs between reproduction and survival in insects. We tested the effects of artificial injury and the resulting impairment on the reproductive costs and behavior of male medflies, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae). Treatment flies were impaired by amputating tarsomere segments 2–5 from the right foreleg at either eclosion or age 22 days. The effect of impairment and age on the cost of reproduction was tested by varying the timing of female availability among the treatments. Courtship behavior and copulation rates were observed hourly from age 2–5 days to determine the effects of impairment on reproductive behavior. Female access combined with the impairment reduced the life expectancy of males more than the impairment alone, whereas the health effect of amputation was influenced by age. Conversely, the risk of death due to impairment was not influenced by the males' mating status prior to amputation. The males' copulation success was reduced due to impairment, whereas courtship behavior was not affected. Impairment does not reduce the males' impulse to mate, but decreases the females' receptivity to copulation, while also increasing the cost of each successful mating. Overall, minor impairment lowers the reproductive success of males and reduces longevity. 相似文献
54.
Yuzuru Sanemitsu Norio Kurihara Minoru Nakajima G. E. McCasland L. F. Johnson L. C. Carey 《Bioscience, biotechnology, and biochemistry》2013,77(5):845-857
Two diastereomers of 6-bromo-1, 2, 3, 4, 5-pentachlorocyclohexane were synthesized from the dl (36/45)-diastereomer of 3, 4, 5, 6-tetrachlorocyclohexene (α-BTC) and the dl (346/5)-diastereomer (γ-BTC) by several stepwise routes. Both of these new products were shown to have the configuration of lindane by NMR studies at 300 MHz and by the synthetic routes. Three diastereomers of 6-bromo-3, 4, 5-trichlorocyclohexene were also prepared and the configurations determined partly by means of 300 MHz NMR. 相似文献
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56.
Linda M. Delahanty Thomas A. Wadden Pamela J. Goodwin Catherine M. Alfano Cynthia A. Thomson Melinda L. Irwin Marian L. Neuhouser Tracy E. Crane Elizabeth Frank Patricia A. Spears Bonnie P. Gillis Dawn L. Hershman Electra D. Paskett Judith Hopkins Vanessa Bernstein Vered Stearns Julia White Clifford Hudis Eric P. Winer Lisa A. Carey Ann H. Partridge Jennifer A. Ligibel 《Obesity (Silver Spring, Md.)》2022,30(1):28-38
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59.
Changes in odor quality discrimination following recovery from olfactory nerve transection 总被引:2,自引:2,他引:2
Following recovery from olfactory nerve transection, animals regain their
ability to discriminate between odors. Odor discrimination is restored
after new neurons establish connections with the olfactory bulb. However,
it is not known if the new connections alter odor quality perception. To
address this question, 20 adult hamsters were first trained to discriminate
between cinnamon and strawberry odors. After reaching criterion (> or =
90% correct response), half of the animals received a bilateral nerve
transection (BTX) and half a surgical sham procedure. Animals were not
tested again until day 40, a point in recovery when connections are
re-established with the bulb. When BTX animals were tested without food
reinforcement, they could not perform the odor discrimination task. Sham
animals, however, could discriminate, demonstrating that the behavioral
response had not been extinguished during the 40 day period. When
reinforcement was resumed, BTX animals were able to discriminate between
cinnamon and strawberry after four test sessions. In addition, their
ability to discriminate between these two familiar odors was no different
than that of BTX and sham animals tested with two novel odors, baby powder
and coffee. These findings suggest that, after recovery from nerve
transection, there are alterations in sensory perception and that
restoration of odor quality discrimination requires that the animal must
again learn to associate individual odor sensations with a behavioral
response.
相似文献
60.