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141.
Pamela E. Ventola Devon R. Oosting Cara M. Keifer Hannah E. Friedman 《The Yale journal of biology and medicine》2015,88(1):37-44
There is a growing literature on children with autism spectrum disorder (ASD) who respond favorably to behavioral treatment, which is often termed “optimal outcome.” Rates and definitions of optimal outcome vary widely. The current case series describes an empirically validated behavioral treatment approach called Pivotal Response Treatment (PRT). We present two preschool-aged children who received an intensive course of PRT and seem to be on a trajectory toward potential optimal outcome. Understanding response to treatment and predictors of response is crucial, not necessarily to predict who may succeed, but to individualize medicine and match children with customized treatment programs that will be best tailored to their unique and varied needs. 相似文献
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144.
Recent evidence indicated that alcohol exposure during the fetal period increases the susceptibility to tumor development in mammary and prostate tissues. Whether fetal alcohol exposure increases the susceptibility to prolactin-producing tumor (prolactinoma) development in the pituitary was studied by employing the animal model of estradiol-induced prolactinomas in Fischer 344 female rats. We employed an animal model of fetal alcohol exposure that simulates binge alcohol drinking during the first two trimesters of human pregnancy and involves feeding pregnant rats with a liquid diet containing 6.7% alcohol during gestational day 7 to day 21. Control rats were pair-fed with isocaloric liquid diet or fed ad libitum with rat chow diet. Adult alcohol exposed and control female offspring rats were used in this study on the day of estrus or after estrogen treatment. Results show that fetal alcohol-exposed rats had increased levels of pituitary weight, pituitary prolactin (PRL) protein and mRNA, and plasma PRL. However, these rats show decreased pituitary levels of dopamine D2 receptor (D2R) mRNA and protein and increased pituitary levels of D2R promoter methylation. Also, they show elevated pituitary mRNA levels of DNA methylating genes (DNMT1, DNMT3b, MeCP2) and histone modifying genes (HDAC2, HDAC4, G9a). When fetal alcohol exposed rats were treated neonatally with a DNA methylation inhibitor 5-Aza deoxycytidine and/or a HDAC inhibitor trichostatin-A their pituitary D2R mRNA, pituitary weights and plasma PRL levels were normalized. These data suggest that fetal alcohol exposure programs the pituitary to increase the susceptibility to the development of prolactinomas possibly by enhancing the methylation of the D2R gene promoter and repressing the synthesis and control of D2R on PRL-producing cells. 相似文献
145.
Susan M. Cheyne Supiansyah Adul Claire J. Neale Carolyn Thompson Cara H. Wilcox Yvette C. Ehlers Smith David A. Ehlers Smith 《Primates; journal of primatology》2018,59(5):437-448
Using direct observations and camera traps at eight sites across Indonesian Borneo we show how red langurs (Presbytis rubicunda) are more terrestrial than previously believed, regularly coming to the ground. This unusual behavior has been found at six of the eight sites surveyed. We find that red langurs come to the ground more frequently in disturbed forests, specifically ones which have been impacted by logging, fire, and hunting, though more data are needed to confirm this as a direct correlation. We also found a trend towards decreased ground use with increased elevation of the habitat. When on the ground, red langurs are predominantly engaged in feeding (50% direct observations, 61% camera traps) and traveling (29% direct observations, 13% camera traps). Red langurs are found on the ground throughout the day, at similar times to activity periods of the apex predator, the Sunda clouded leopard (Neofelis diardi). We suggest that ground use by red langurs could be an adaptation to disturbed forest to exploit additional food sources and to facilitate travel. 相似文献
146.
Point mutations at the catalytic site of PCSK9 inhibit folding,autoprocessing, and interaction with the LDL receptor
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Colin W. Garvie Cara V. Fraley Nadine H. Elowe Elizabeth K. Culyba Christopher T. Lemke Brian K. Hubbard Virendar K. Kaushik Douglas S. Daniels 《Protein science : a publication of the Protein Society》2016,25(11):2018-2027
Circulating low‐density lipoprotein cholesterol (LDLc) is regulated by membrane‐bound LDL receptor (LDLr). Upon LDLc and LDLr interaction the complex is internalized by the cell, leading to LDLc degradation and LDLr recycling back to the cell surface. The proprotein convertase subtilisin/kexin type 9 (PCSK9) protein regulates this cycling. PCSK9 is secreted from the cell and binds LDLr. When the complex is internalized, PCSK9 prevents LDLr from shuttling back to the surface and instead targets it for degradation. PCSK9 is a serine protease expressed as a zymogen that undergoes autoproteolysis, though the two resulting protein domains remain stably associated as a heterodimer. This PCSK9 autoprocessing is required for the protein to be secreted from the cell. To date, direct analysis of PCSK9 autoprocessing has proven challenging, as no catalytically active zymogen has been isolated. A PCSK9 loss‐of‐function point mutation (Q152H) that reduces LDLc levels two‐fold was identified in a patient population. LDLc reduction was attributed to a lack of PCSK9(Q152H) autoprocessing preventing secretion of the protein. We have isolated a zymogen form of PCSK9, PCSK9(Q152H), and a related mutation (Q152N), that can undergo slow autoproteolysis. We show that the point mutation prevents the formation of the mature form of PCSK9 by hindering folding, reducing the rate of autoproteolysis, and destabilizing the heterodimeric form of the protein. In addition, we show that the zymogen form of PCSK9 adopts a structure that is distinct from the processed form and is unable to bind a mimetic peptide based on the EGF‐A domain of the LDLr. 相似文献
147.
Indirect Effects of an Existing Wind Energy Facility on Lekking Behavior of Greater Prairie‐Chickens
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Jennifer A. Smith Cara E. Whalen Mary Bomberger Brown Larkin A. Powell 《Ethology : formerly Zeitschrift fur Tierpsychologie》2016,122(5):419-429
Rapid expansion of the wind energy industry has raised concerns about the potential effects of anthropogenic disturbance on prairie grouse. While efforts have been made to address the effects of wind energy facilities on measures of fitness, their effect on the behaviors of prairie grouse has been largely neglected. To address these concerns, we investigated the effects of an existing wind energy facility in Nebraska that became operational in 2005 on the lekking behavior of male greater prairie‐chickens Tympanuchus cupido pinnatus between March and May 2013. Given the potential for disturbance caused by wind turbine noise to disrupt acoustic communication and thus behavior, we predicted that males at leks close to, compared to far from, the wind energy facility would spend more time in agonistic behaviors, and less in booming displays. Given the potential for wind turbine noise to reduce the number of females attending leks (hereafter ‘female lek attendance’), we also predicted that males at leks close to the wind energy facility would spend more time in non‐breeding behaviors and less time in breeding behaviors than males farther from the facility. Although we found no effect of the wind energy facility on female lek attendance, males at leks closer to the wind energy facility spent less time in non‐breeding behaviors than those at leks farther away. However, distance from the wind energy facility had no effect on time spent performing booming displays, flutter jumps, or in agonistic behaviors. Given that lekking behaviors of males influence mating success, our results may have consequences for the fitness of prairie grouse breeding in the vicinity of wind energy facilities. 相似文献
148.
The movement of Samanea saman (Jacq.) Merrill leaflets is a consequence of the re-distribution of K+ and anions between motor cells on opposite sides of the pulvinus. We used a K+-sensitive microelectrode to study dynamic changes in K+ transport through motor-cell membranes during and immediately after change in illumination. Potassium-ion-sensitive and reference microelectrodes were inserted into extensor or flexor tissue of a whole pulvinus in white light (WL). A brief pulse of red light (RL) followed by darkness (D) (a) increased K+ activity in the extensor apoplast, indicating K+ release by the protoplast; and (b) decreased K+ activity in the flexor apoplast, indicating K+ uptake by the protoplast. White light after 35–40 min D reversed K+ activity in the extensor apoplast to approximately its original value. Blue light substituted partially for WL in this regard. Potassium-ion activity in the flexor apoplast reverted to approximately its original value after 2 h, with or without white illumination. Our data support the hypothesis that K+ efflux from extensor cells and K+ uptake by flexor cells following a WLRLD transition occurs by way of K+ channels.Abbreviations L
light
- WL
white light
- RL
red light
- BL
blue light
- D
darkness 相似文献
149.
Cara E. Richards 《American anthropologist》1969,71(6):1115-1117
Anthropologists have long been aware of the difference between the ideal pattern in society (what people think should or should not be done) and real behavior (what actually is done). This article calls attention to the importance of a third element, presumed behavior, or what people think is being done in the society. Since people tend to act on the basis of what they think others are doing (which may not coincide at all with what people are actually doing, or with the ideal pattern) knowledge of the presumed behavior is highly significant in understanding and predicting social behavior. 相似文献
150.
Cloning and expression of a gene segment encoding the enzymatic moiety of Pseudomonas aeruginosa exotoxin A. 总被引:6,自引:3,他引:3
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Using the broad-host-range plasmid vector pRO1614, we cloned a segment of the gene from Pseudomonas aeruginosa PA103 encoding the enzymatically active part of the exotoxin A protein. Expression of the cloned gene segment has been achieved both in Escherichia coli and in a nontoxigenic P. aeruginosa host, as assayed by the production of exotoxin A-related antigen and by the ability of the gene product to ADP-ribosylate elongation factor 2. Western blot hybridization analysis revealed a series of polypeptides antigenically related to exotoxin A, the largest of which had a molecular weight of ca. 50,000. 相似文献