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971.
Abstract Annual cycles in hematological parameters, organ weights, and total body fat were measured in two species of mice from a prairie environment. Hematocrit was higher in winter in both Microtus ochrogaster and Peromyscus maniculatus. Plasma protein concentration decreased in winter in both species. Liver, kidneys, and adrenal glands were larger in female P. maniculatus than in males. Greatest liver and kidney size occurred during lactation. Total body lipid was about 5 to 7% of live body weight throughout the year, providing enough energy to survive only about one day of fasting. Adaptive shifts in bodily functions can be expected to coincide with periods of unusual energy expenditure such as lactation and winter. In these mice conserving energy seems to be a more important survival strategy than storing it. 相似文献
972.
Laia Batalla-Carrera Ana Morton Sergi Santamaria Fernando García-del-Pino 《Biocontrol Science and Technology》2013,23(1):101-125
An approach to ensure effective pest biocontrol would be to select native isolates of biological control agents (BCAs). A survey to isolate entomopathogenic fungi (EPF) from a hazelnut growing area has been carried out. EPF were recovered from 133 of the 295 soil samples. The main species isolated were Metarhizium anisopliae sensu lato (36%) and Beauveria bassiana sensu lato (42.8%). With regard to controlling abiotic factors, altitude had an effect on the distribution of B. bassiana, but not on M. anisopliae. Cropping system did not have an effect on the occurrence of these EPF, while pH appeared as a predictive variable for both. In addition, we tested the virulence of six of these isolates: three M. anisopliae and three of B. bassiana against larvae of Curculio nucum L. The highest larval mortality (reaching 80%) was due to M. anisopliae (strain 34) when applied in simultaneous combination with four entomopathogenic nematode species: Steinernema carpocapsae (strain B14), Steinernema feltiae (strain D114), Steinernema. sp. (strain D122) and Heterorhabditis bacteriophora (strain DG46). The effect of nematodes was greater and no antagonistic or synergistic effects were observed. 相似文献
973.
Talkowski ME Mullegama SV Rosenfeld JA van Bon BW Shen Y Repnikova EA Gastier-Foster J Thrush DL Kathiresan S Ruderfer DM Chiang C Hanscom C Ernst C Lindgren AM Morton CC An Y Astbury C Brueton LA Lichtenbelt KD Ades LC Fichera M Romano C Innis JW Williams CA Bartholomew D Van Allen MI Parikh A Zhang L Wu BL Pyatt RE Schwartz S Shaffer LG de Vries BB Gusella JF Elsea SH 《American journal of human genetics》2011,(4):551-563
Persons with neurodevelopmental disorders or autism spectrum disorder (ASD) often harbor chromosomal microdeletions, yet the individual genetic contributors within these regions have not been systematically evaluated. We established a consortium of clinical diagnostic and research laboratories to accumulate a large cohort with genetic alterations of chromosomal region 2q23.1 and acquired 65 subjects with microdeletion or translocation. We sequenced translocation breakpoints; aligned microdeletions to determine the critical region; assessed effects on mRNA expression; and examined medical records, photos, and clinical evaluations. We identified a single gene, methyl-CpG-binding domain 5 (MBD5), as the only locus that defined the critical region. Partial or complete deletion of MBD5 was associated with haploinsufficiency of mRNA expression, intellectual disability, epilepsy, and autistic features. Fourteen alterations, including partial deletions of noncoding regions not typically captured or considered pathogenic by current diagnostic screening, disrupted MBD5 alone. Expression profiles and clinical characteristics were largely indistinguishable between MBD5-specific alteration and deletion of the entire 2q23.1 interval. No copy-number alterations of MBD5 were observed in 7878 controls, suggesting MBD5 alterations are highly penetrant. We surveyed MBD5 coding variations among 747 ASD subjects compared to 2043 non-ASD subjects analyzed by whole-exome sequencing and detected an association with a highly conserved methyl-CpG-binding domain missense variant, p.79Gly>Glu (c.236G>A) (p = 0.012). These results suggest that genetic alterations of MBD5 cause features of 2q23.1 microdeletion syndrome and that this epigenetic regulator significantly contributes to ASD risk, warranting further consideration in research and clinical diagnostic screening and highlighting the importance of chromatin remodeling in the etiology of these complex disorders. 相似文献
974.
Saadi I Alkuraya FS Gisselbrecht SS Goessling W Cavallesco R Turbe-Doan A Petrin AL Harris J Siddiqui U Grix AW Hove HD Leboulch P Glover TW Morton CC Richieri-Costa A Murray JC Erickson RP Maas RL 《American journal of human genetics》2011,(1):44-55
Genetic mutations responsible for oblique facial clefts (ObFC), a unique class of facial malformations, are largely unknown. We show that loss-of-function mutations in SPECC1L are pathogenic for this human developmental disorder and that SPECC1L is a critical organizer of vertebrate facial morphogenesis. During murine embryogenesis, Specc1l is expressed in cell populations of the developing facial primordial, which proliferate and fuse to form the face. In zebrafish, knockdown of a SPECC1L homolog produces a faceless phenotype with loss of jaw and facial structures, and knockdown in Drosophila phenocopies mutants in the integrin signaling pathway that exhibit cell-migration and -adhesion defects. Furthermore, in mammalian cells, SPECC1L colocalizes with both tubulin and actin, and its deficiency results in defective actin-cytoskeleton reorganization, as well as abnormal cell adhesion and migration. Collectively, these data demonstrate that SPECC1L functions in actin-cytoskeleton reorganization and is required for proper facial morphogenesis. 相似文献
975.
Population structure dictates the evolution of each population, and thus, the species as a whole. Incorporating spatial variables with population genetic statistics allows for greater discovery beyond traditional population genetics alone and can inform management decisions. The understanding of population structure in Hessian fly, Mayetiola destructor (Say), a pest of wheat, has been limited in the past. We scored 14 microsatellite loci from 12 collections of Hessian fly in the southeastern United States. Through Bayesian clustering analysis, we found two major populations of Hessian fly covering the entire southeastern United States. We evaluated correlations between agriculturally significant spatial variables and population genetic differentiation to test if genetic structure has an ecological component in a wheat agro-ecosystem. Our results suggest the total amount of alternative host plants in the county may be driving some genetic differentiation. Although planting date may also be influential, geographic distance, mean annual temperature, and harvested wheat for grain do not seem to be contributing factors. The ecological or spatial component to population structure, however, may be minimal compared to factors such as genetic drift. 相似文献
976.
977.
The viral RNA-dependent RNA polymerase (RdRp) is essential for multiplication of all RNA viruses. The sequence diversity of an RNA virus population contributes to its ability to infect the host. This diversity emanates from errors made by the RdRp during RNA synthesis. The physical basis for RdRp fidelity is unclear but is linked to conformational changes occurring during the nucleotide-addition cycle. To understand RdRp dynamics that might influence RdRp function, we have analyzed all-atom molecular dynamics simulations on the nanosecond timescale of four RdRps from the picornavirus family that exhibit 30-74% sequence identity. Principal component analysis showed that the major motions observed during the simulations derived from conserved structural motifs and regions of known function. The dynamics of residues participating in the same biochemical property, for example, RNA binding, nucleotide binding or catalysis, were correlated even when spatially distant on the RdRp structure. The conserved and correlated dynamics of functional structural elements suggest coevolution of dynamics with structure and function of the RdRp. Crystal structures of all picornavirus RdRps exhibit a template-nascent RNA duplex channel too small to fully accommodate duplex RNA. Simulations revealed opening and closing motions of the RNA and nucleoside triphosphate channels, which might be relevant to nucleoside triphosphate entry, inorganic pyrophosphate exit and translocation. A role for nanosecond timescale dynamics in RdRp fidelity is supported by the altered dynamics of the high-fidelity G64S derivative of PV RdRp relative to wild-type enzyme. 相似文献
978.
Trujillo JI Huang W Hughes RO Rogier DJ Turner SR Devraj R Morton PA Xue CB Chao G Covington MB Newton RC Metcalf B 《Bioorganic & medicinal chemistry letters》2011,21(6):1827-1831
This report describes the design and synthesis of a series of CCR2 antagonists incorporating novel non-aryl/heteroaryl RHS (right hand side) motifs. Previous SAR in the area has suggested an aryl/heteroaryl substituent as a necessary structural feature for binding to the CCR2 receptor. Herein we describe the SAR with regards to potency (binding to hCCR2), dofetilide activity and metabolic stability (in vitro HLM) for this series. The resulting outcome was the identification of compounds with excellent properties for the investigation of the role of CCR2 in disease. 相似文献
979.
Live animals and cadavers are integral to veterinary education. In the year of this survey (2008), and in at least the five preceding years, cadavers obtained by euthanasia of healthy pound dogs and ex-racing greyhounds were dissected by students, during their veterinary anatomy classes at the University of Queensland School of Veterinary Science. Students may have ethical concerns about this. An alternative approach was to use donated dog cadavers. These are owned pet dogs that have died of natural causes or have been euthanised for medical reasons, and have been donated by their owners for the purposes of veterinary education. Veterinary students at the School were surveyed in 2008, in order to determine their preferences for cadaver source. Data from 406 questionnaires were analysed. Third-year and fifth-year veterinary students were more likely than first-year students to prefer pound-dog/greyhound cadavers over donated cadavers for anatomy dissection (p ≤ 0.002). Between 32% and 45% of the students had no preference for either source of cadaver. These findings are consistent with the hypothesis that veterinary students become more accepting of the euthanasia of unwanted healthy animals for education as they progress through the veterinary programme, in contexts such as the current study. This could occur due to increased acceptance of the euthanasia of healthy animals generally, a decline in moral development, desensitisation, and/or the belief that healthy animal cadavers offer a superior learning experience. 相似文献
980.