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121.
122.
Patrick D. Brandt Susi Sturzenegger Varvayanis Tracey Baas Amanda F. Bolgioni Janet Alder Kimberly A. Petrie Isabel Dominguez Abigail M. Brown C. Abigail Stayart Harinder Singh Audra Van Wart Christine S. Chow Ambika Mathur Barbara M. Schreiber David A. Fruman Brent Bowden Christopher A. Wiesen Yvonne M. Golightly Chris E. Holmquist Daniel Arneman Joshua D. Hall Linda E. Hyman Kathleen L. Gould Roger Chalkley Patrick J. Brennwald Rebekah L. Layton 《PLoS biology》2021,19(7)
123.
Brent A. Lasker Melissa Bell Hans-Peter Klenk Cathrin Spröer Peter Schumann June M. Brown 《Antonie van Leeuwenhoek》2014,106(3):543-553
Nocardia species are ubiquitous in the environment with an increasing number of species isolated from clinical sources. From 2005 to 2009, eight isolates (W9042, W9247, W9290, W9319, W9846, W9851T, W9865, and W9908) were obtained from eight patients from three states in the United States and Canada; all were from males ranging in age from 47 to 81 years old; and all were obtained from finger (n = 5) or leg (n = 3) wounds. Isolates were characterized by polyphasic analysis using molecular, phenotypic, morphologic and chemotaxonomic methods. Sequence analysis of 16S rRNA gene sequences showed the eight isolates are 100 % identical to each other and belong in the genus Nocardia. The nearest phylogenetically related neighbours were found to be the type strains for Nocardia altamirensis (99.33 % sequence similarity), Nocardia brasiliensis (99.37 %), Nocardia iowensis (98.95 %) and Nocardia tenerifensis (98.44 %). The G+C content of isolate W9851T was determined to be 68.4 mol %. The DNA–DNA relatedness between strain W9851T and the N. brasiliensis type strain was 72.8 % and 65.8 % when measured in the laboratory and in silico from genome sequences, respectively, and 95.6 % ANI. Whole-cell peptidoglycan was found to contain meso-diaminopimelic acid; MK-8-(H4)ω-cyc was identified as the major menaquinone; the major fatty acids were identified as C16:0, 10 Me C18:0, and C18:1 w9c, the predominant phospholipids were found to include diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositol mannosides; whole-cell sugars detected were arabinose and galactose; and mycolic acids ranging from 38 to 60 carbon atoms were found to be present. These chemotaxonomic analyses are consistent with assignment of the isolates to the genus Nocardia. Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectra of the clinical isolates showed genus and species level profiles that were different from other Nocardia species. All isolates were resistant to ciprofloxacin, clarithromycin and imipenem but were susceptible to amikacin, amoxicillin/clavulanate, linezolid and trimethoprim/sulfamethoxazole. The results of our polyphasic analysis suggest the new isolates obtained from wound infections represent a novel species within the genus Nocardia, for which the name Nocardia vulneris sp. nov. is proposed, with strain W9851T (= DSM 45737T = CCUG 62683T = NBRC 108936T) as the type strain. 相似文献
124.
Richard?M. Venable Alexander?J. Sodt Brent Rogaski Huan Rui Elizabeth Hatcher Alexander?D. MacKerell Jr. Richard?W. Pastor Jeffery?B. Klauda 《Biophysical journal》2014,106(1):134-144
Kv channels detect changes in the membrane potential via their voltage-sensing domains (VSDs) that control the status of the S6 bundle crossing (BC) gate. The movement of the VSDs results in a transfer of the S4 gating charges across the cell membrane but only the last 10–20% of the total gating charge movement is associated with BC gate opening, which involves cooperative transition(s) in the subunits. Substituting the proline residue P475 in the S6 of the Shaker channel by a glycine or alanine causes a considerable shift in the voltage-dependence of the cooperative transition(s) of BC gate opening, effectively isolating the late gating charge component from the other gating charge that originates from earlier VSD movements. Interestingly, both mutations also abolished Shaker’s sensitivity to 4-aminopyridine, which is a pharmacological tool to isolate the late gating charge component. The alanine substitution (that would promote a α-helical configuration compared to proline) resulted in the largest separation of both gating charge components; therefore, BC gate flexibility appears to be important for enabling the late cooperative step of channel opening. 相似文献
125.
Richard M. Venable Alexander J. Sodt Brent Rogaski Huan Rui Elizabeth Hatcher Alexander D. MacKerell Jr. Richard W. Pastor Jeffery B. Klauda 《Biophysical journal》2014
The C36 CHARMM lipid force field has been extended to include sphingolipids, via a combination of high-level quantum mechanical calculations on small molecule fragments, and validation by extensive molecular dynamics simulations on N-palmitoyl and N-stearoyl sphingomyelin. NMR data on these two molecules from several studies in bilayers and micelles played a strong role in the development and testing of the force field parameters. Most previous force fields for sphingomyelins were developed before the availability of the detailed NMR data and relied on x-ray diffraction of bilayers alone for the validation; these are shown to be too dense in the bilayer plane based on published chain order parameter data from simulations and experiments. The present simulations reveal O-H:::O-P intralipid hydrogen bonding occurs 99% of the time, and interlipid N-H:::O=C (26-29%, depending on the lipid) and N-H:::O-H (17–19%). The interlipid hydrogen bonds are long lived, showing decay times of 50 ns, and forming strings of lipids, and leading to reorientational correlation time of nearly 100 ns. The spontaneous radius of curvature for pure N-palmitoyl sphingomyelin bilayers is estimated to be 43–100 Å, depending on the assumptions made in assigning a bending constant; this unusual positive curvature for a two-tailed neutral lipid is likely associated with hydrogen bond networks involving the NH of the sphingosine group. 相似文献
126.
Higham JP Brent LJ Dubuc C Accamando AK Engelhardt A Gerald MS Heistermann M Stevens M 《Behavioral ecology》2010,21(4):739-746
Animal coloration has provided many classical examples of both natural and sexual selection. Methods to study color signals range from human assessment to models of receiver vision, with objective measurements commonly involving spectrometry or digital photography. However, signal assessment by a receiver is not objective but linked to receiver perception. Here, we use standardized digital photographs of female rhesus macaque (Macaca mulatta) face and hindquarter regions, combined with estimates of the timing of the female fertile phase, to assess how color varies with respect to this timing. We compare objective color measures (camera sensor responses) with models of rhesus vision (retinal receptor stimulation and visual discriminability). Due to differences in spectral separation between camera sensors and rhesus receptors, camera measures overestimated color variation and underestimated luminance variation compared with rhesus macaques. Consequently, objective digital camera measurements can produce statistically significant relationships that are probably undetectable to rhesus macaques, and hence biologically irrelevant, while missing variation in the measure that may be relevant. Discrimination modeling provided results that were most meaningful (as they were directly related to receiver perception) and were easiest to relate to underlying physiology. Further, this gave new insight into the function of such signals, revealing perceptually salient signal luminance changes outside of the fertile phase that could potentially enhance paternity confusion. Our study demonstrates how, even for species with similar visual systems to humans, models of vision may provide more accurate and meaningful information on the form and function of visual signals than objective color measures do. 相似文献
127.
Background
The prevention of head injuries in alpine activities has focused on helmets. However, no systematic review has examined the effect of helmets on head and neck injuries among skiers and snowboarders.Methods
We searched electronic databases, conference proceedings and reference lists using a combination of the key words “head injury or head trauma,” “helmet” and “skiing or snowboarding.” We included studies that used a control group; compared skiers or snowboarders with and without helmets; and measured at least one objectively quantified outcome (e.g., head injury, and neck or cervical injury).Results
We included 10 case–control, 1 case–control/case-crossover and 1 cohort study in our analysis. The pooled odds ratio (OR) indicated that skiers and snowboarders with a helmet were significantly less likely than those without a helmet to have a head injury (OR 0.65, 95% confidence interval [CI] 0.55–0.79). The result was similar for studies that used controls without an injury (OR 0.61, 95% CI 0.36–0.92), those that used controls with an injury other than a head or neck injury (OR 0.63, 95% CI 0.52–0.80) and studies that included children under the age of 13 years (OR 0.41, 95% CI 0.27–0.59). Helmets were not associated with an increased risk of neck injury (OR 0.89, 95% CI 0.72–1.09).Interpretation
Our findings show that helmets reduce the risk of head injury among skiers and snowboarders with no evidence of an increased risk of neck injury.Skiing and snowboarding are popular winter activities.1 Estimates from numerous countries indicate that head injuries account for 9% to 19%, and neck injuries for 1% to 4%, of all injuries reported by ski patrols and emergency departments.2–11 Rates of head and neck injuries have been reported between 0.09 and 0.46 per 1000 outings.12 Head and neck injuries are disproportionately represented in cases of severe trauma, and traumatic brain injury is the leading cause of death and serious injury among skiers and snow-boarders.13 As far back as 1983, Oh and Schmid recommended mandatory helmet use for children while skiing.14Many studies of the relation between helmet use and head injuries among skiers and snowboarders have found a protective effect.15–24 It has been suggested that the use of helmets may increase the risk of neck injury in a crash or fall.25 This may be more evident among children because they have a greater head:body ratio than adults, and the additional size and weight of the helmet may increase the risk of neck injury in an otherwise routine fall.26 We conducted a systematic review of the effect of helmets on head and neck injuries among skiers and snowboarders. 相似文献128.
Thommey P. Thomas Baohua Huang Ankur Desai Hong Zong Xue-min Cheng Alina Kotlyar Pascale R. Leroueil Thomas Dunham Abraham van der Spek Brent B. Ward James R. Baker 《Bioorganic & medicinal chemistry letters》2010,20(21):6250-6253
Two morphine prodrugs (‘PDA’ and ‘PDB’) were synthesized and the kinetics of esterase-mediated morphine release from these prodrugs were determined when incubated with plasma from different animal species. Morphine was rapidly released from PDA by all species plasma with the maximum reached within 5–10 min; the released morphine was biologically active as determined by an in vitro cAMP assay. The morphine was released from PDB at a slower and species-dependent rate (mouse > rat > guinea pig > human). Morphine’s release from PDB appeared to be mediated by carboxyl esterases as the release was inhibited by the carboxyl esterase inhibitor benzil. PDA nor PDB induce cytotoxicity in the neuronal cell lines SK-NSH and SH-SY5Y. The carboxyl and amino functional moieties present on the linker portions of PDA and PDB, respectively, may facilitate their conjugation to nanoparticles to tailor morphine pharmacokinetics and specific targeting. These studies suggest the potential clinical utility of these prodrugs for morphine release at desired rates by administration of their mixture at selected ratios. 相似文献
129.
Christiana M. A. Faria Eugenia Zarza Víctor H. Reynoso Brent C. Emerson 《Conservation Genetics》2010,11(5):1645-1652
Because of female-biased illegal harvesting, knowledge about the genetic mating system of the black spiny-tailed iguana Ctenosaura pectinata is of primary interest for the conservation of this threatened species. Based on the high levels of multiple paternity found
in clutches of many other reptiles, particularly in lizards, it is hypothesised that multiple paternity may also be common
in black iguanas. This was investigated by using microsatellite DNA to estimate the number of males siring nine litters (9
mothers, 121 offspring genotyped at ten polymorphic loci) of black iguanas. Contrary to expectations, only 11% of sampled
black iguana females produced litters consistent with being sired by multiple males. These data are the first evidence for
the predominance of single paternity within an iguanid lizard, and suggest that black iguana may be more susceptible to loss
of genetic variation in the face of gender-biased over-hunting pressure than previously thought. 相似文献
130.
Andréia S Lessa Bruno D Paredes Juliana V Dias Adriana B Carvalho Luiz Fernando Quintanilha Christina M Takiya Bernardo R Tura Guilherme FM Rezende Antonio C Campos de Carvalho Célia MC Resende Regina CS Goldenberg 《BMC veterinary research》2010,6(1):1-10