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131.
Maria Ciofani Aviv Madar Carolina GalanMacLean Sellars Kieran MaceFlorencia Pauli Ashish AgarwalWendy Huang Christopher N. ParkurstMichael Muratet Kim M. NewberrySarah Meadows Alex GreenfieldYi Yang Preti JainFrancis K. Kirigin Carmen BirchmeierErwin F. Wagner Kenneth M. Murphy Richard M. MyersRichard Bonneau Dan R. Littman 《Cell》2012,151(2):289-303
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133.
Nichole Shelmidine Carola Borries Colleen McCann 《American journal of primatology》2009,71(10):852-859
Within phylogenetic limits reproductive characteristics of a given species may vary between populations in response to ecological and social factors. For instance, in environments where high quality nutrition is readily available, the onset and speed of reproduction are often accelerated. Other influencing factors might be maternal experience or the sex of the infant. Here we present data on reproductive characteristics for the silvered leaf monkey (Trachypithecus cristatus), a medium‐sized Asian colobine housed at the Wildlife Conservation Society's Bronx Zoo as a one‐male group. To place the species into an appropriate phylogenetic context, we limited our comparison to other colobine species. Demographic data span 21.4 years (October 1985 to March 2007) and derive from 30 adult females (128.0 female years). Detailed behavioral data stem from a 2.2 years study (November 2002 to January 2005; 734 days, 4,225 hr). As in other Asian colobines, receptive periods were short (mean=4.3 days, n=68). This is expected for one‐male groups where receptivity likely indicates, rather than conceals, ovulation. Gestation length was estimated based on a change in the pattern of sexual behavior (mean=194.6 days, n=7). It fell within the range reported for the taxon. Births occurred year round, at an early age (mean=2.9 years, n=8), at short intervals (mean=14.9 months, n=59) in combination with a short lactation (mean 12.1 months, n=9) likely due to the nearly unlimited availability of nutrition in this zoo setting. Primiparous females tended to have a longer first interbirth interval but infant survival rates were similar to multipara possibly due to the absence of predators. Maternal investment was independent of the infant's sex and birth sex ratio was even. Our results emphasize that when interpreted with caution, zoo populations yield realistic reproductive characteristics that can help fill the gap in our knowledge about colobine life history. Am. J. Primatol. 71:852–859, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
134.
Takashi Uchimura Yoshihiro Komatsu Momo Tanaka Kelly L. McCann Yuji Mishina 《Genesis (New York, N.Y. : 2000)》2009,47(6):374-384
Bone morphogenetic proteins (BMPs) have multiple roles during embryogenesis. Current data indicate that the dosage of BMPs is tightly regulated for normal development in mice. Since Bmp2 or Bmp4 homozygous mutant mice show early embryonic lethality, we generated compound heterozygous mice for Bmp2 and Bmp4 to explore the impact of lowered dosage of these BMP ligands. Genotyping pups bred between Bmp2 and Bmp4 heterozygous mice revealed that the ratio of adult compound heterozygous mice for Bmp2 and Bmp4 is much lower than expected. During embryogenesis, the compound heterozygous embryos showed several abnormalities, including defects in eye formation, body wall closure defects, and ventricular septal defects (VSD) in the heart. However, the ratio of the compound heterozygous embryos was the same as expected. Caesarean sections at E18.5 revealed that half of the compound heterozygotes died soon after birth, and the majority of the dead individuals exhibited VSD. Survivors were able to grow to adults, but their body weight was significantly lower than control littermates. They demonstrated progressive abnormalities in the heart, eventually showing a branched leaflet in atrioventricular valves. These results suggest that the dosage of both BMP2 and 4 is critical for functional heart formation during embryogenesis and after birth. genesis 47:374–384, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
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136.
Xavier Didelot Bo Pang Zhemin Zhou Angela McCann Peixiang Ni Dongfang Li Mark Achtman Biao Kan 《PLoS genetics》2015,11(3)
Epidemics and pandemics of cholera, a severe diarrheal disease, have occurred since the early 19th century and waves of epidemic disease continue today. Cholera epidemics are caused by individual, genetically monomorphic lineages of Vibrio cholerae: the ongoing seventh pandemic, which has spread globally since 1961, is associated with lineage L2 of biotype El Tor. Previous genomic studies of the epidemiology of the seventh pandemic identified three successive sub-lineages within L2, designated waves 1 to 3, which spread globally from the Bay of Bengal on multiple occasions. However, these studies did not include samples from China, which also experienced multiple epidemics of cholera in recent decades. We sequenced the genomes of 71 strains isolated in China between 1961 and 2010, as well as eight from other sources, and compared them with 181 published genomes. The results indicated that outbreaks in China between 1960 and 1990 were associated with wave 1 whereas later outbreaks were associated with wave 2. However, the previously defined waves overlapped temporally, and are an inadequate representation of the shape of the global genealogy. We therefore suggest replacing them by a series of tightly delineated clades. Between 1960 and 1990 multiple such clades were imported into China, underwent further microevolution there and then spread to other countries. China was thus both a sink and source during the pandemic spread of V. cholerae, and needs to be included in reconstructions of the global patterns of spread of cholera. 相似文献
137.
Glycerophosphodiesterase (GpdQ) from Enterobacter aerogenes is a binuclear metallohydrolase that catalyzes the breakdown of a broad range of phosphate ester substrates, and it is of interest for its potential application in the destruction of organophosphate nerve agents and pesticides. The reaction mechanism of GpdQ has been proposed to involve a nucleophilic attack by a terminally bound hydroxide molecule. The hydroxide species bridging the two metal ions is suggested to activate the nucleophile, thus favoring a sequential rather than a processive mechanism of action. Here, the hydrolysis of the two ester bonds in the substrate bis(para-nitrophenyl) phosphate (bpNPP) is probed using 31P NMR. The kinetic rates measured compare well with those determined spectrophotometrically. Furthermore, the data indicate that the diester bonds are cleaved in two separate (non-processive) reactions, indicating that only a single nucleophile (the terminal hydroxide molecule) is likely to be employed as a nucleophile for GpdQ. 相似文献
138.
Fiona E McCann Andrew C Palfreeman Melanie Andrews Dany P Perocheau Julia J Inglis Peter Schafer Marc Feldmann Richard O Williams Fionula M Brennan 《Arthritis research & therapy》2010,12(3):R107
Introduction
Type 4 phosphodiesterases (PDE4) play an important role in immune cells through the hydrolysis of the second messenger, cAMP. Inhibition of PDE4 has previously been shown to suppress immune and inflammatory responses, demonstrating PDE4 to be a valid therapeutic target for immune-mediated pathologies. We assessed the anti-inflammatory effects of a novel PDE4 inhibitor, apremilast, in human synovial cells from rheumatoid arthritis (RA) patients, as well as two murine models of arthritis. 相似文献139.
Kieran M. Clements Clyde E. Sorenson Brian M. Wiegmann Paul A. Neese R. Michael Roe 《Entomologia Experimentalis et Applicata》2000,95(3):269-281
Prior to designation as distinct species, an appellation presently in question, the tobacco aphid, Myzus nicotianae Blackman (Homoptera: Aphididae), was classified as a tobacco-feeding form of the green peach aphid, Myzus persicae (Sulzer). In this study, RAPD polymorphisms distinguished members of the Myzus persicae complex (M. persicae and M. nicotianae) from three outgroup Myzus species (M. cerasi (F.), M. hemerocallis Takahashi, and M. varians Davidson). Polymorphisms within the complex did not separate populations on the basis of host association (tobacco versus other host plants) or geographic origin (collections from the United States, Europe, and Japan). Similarly, while GC-MS analysis of cuticular hydrocarbon profiles revealed both developmental and inter-populational differences within the M. persicae complex, it did not separate populations of tobacco feeding aphids from those collected off non-tobacco hosts. Finally, with the exception of their responses to a choice between lettuce and collards, the host preference behavior of a green peach aphid population, a red tobacco aphid population, and a green tobacco aphid population was indistinguishable in host preference experiments. These results add to a growing body of evidence suggesting M. nicotianae and M. persicae are conspecific. 相似文献
140.
Michael R. Wilson Kieran P. O'Dea Anthony D. Dorr Hirotoshi Yamamoto Michael E. Goddard Masao Takata 《PloS one》2010,5(7)