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61.
Torsten Wronski Timothy Wacher Robert L. Hammond Bruce Winney Kris J. Hundertmark Mark J. Blacket 《分类学与生物多样性》2013,11(1):119-129
Mountain gazelles (Gazella gazella) rank among the most critically endangered mammals on the Arabian Peninsula. Past conservation efforts have been plagued by confusion about the phylogenetic relationship among various ‘phenotypically discernable’ populations, and even the question of species boundaries was far from being certain. This lack of knowledge has had a direct impact on conservation measures, especially ex situ breeding programmes, hampering the assignment of captive stocks to potential conservation units. Here, we provide a phylogenetic framework, based on the analysis of mtDNA sequences (360 bp cytochrome b and 213 bp Control Region) of 126 individuals collected from the wild throughout the Arabian Peninsula and from captive stocks. Our analyses revealed two reciprocally monophyletic genetic lineages within the presumed species Gazella gazella: one ‘northern clade’ on the Golan Heights (Israel/Syrian border) and one genetically diverse larger clade from the rest of the Arabian Peninsula including the Arava Valley (Negev, Israel). Applying the Strict Phylogenetic Species Concept (sensu Mishler & Theriot, 2000) allows assigning species status to these two major clades. 相似文献
62.
Bianca Romeu Fábio G. Daura-Jorge Philip S. Hammond Pedro V. Castilho Paulo C. Simões-Lopes 《Marine Mammal Science》2024,40(1):222-236
Some dolphin species produce signature whistles, which may allow the identification of individual dolphins using passive acoustic monitoring (PAM). Identifying individuals by their sounds may enhance the opportunities for monitoring and addressing biological and ecological questions about these species. Here, we explored the potential of signature whistles to investigate ecological aspects of a resident bottlenose dolphin population. Using a limited data set, with few individuals recognized by signature whistles, combined with spatial capture-recapture (SCR) methods, we investigated how effective such approach is describing spatial use patterns and estimating density for this population. The data were collected using 4–6 stationary bottom-moored recorders. Since only eight signature whistles were identified, our density estimate may represent a subset of the entire population. However, even with only a few signature whistles identified, our results confirmed the center of the core area used by these dolphins as the area with the highest encounter probability. In addition, our results provided evidence that these dolphins have the same spatial use pattern at night as during the day. This study shows that SCR analysis of signature whistle data can improve our ecological knowledge and understanding of dolphin populations. 相似文献
63.
Kasperavičiūtė D Catarino CB Chinthapalli K Clayton LM Thom M Martinian L Cohen H Adalat S Bockenhauer D Pope SA Lench N Koltzenburg M Duncan JS Hammond P Hennekam RC Land JM Sisodiya SM 《PloS one》2011,6(8):e23182
Background
Patients with epilepsy often suffer from other important conditions. The existence of such co-morbidities is frequently not recognized and their relationship with epilepsy usually remains unexplained.Methodology/Principal Findings
We describe three patients with common, sporadic, non-syndromic epilepsies in whom large genomic microdeletions were found during a study of genetic susceptibility to epilepsy. We performed detailed gene-driven clinical investigations in each patient. Disruption of the function of genes in the deleted regions can explain co-morbidities in these patients.Conclusions/Significance
Co-morbidities in patients with epilepsy can be part of a genomic abnormality even in the absence of (known) congenital malformations or intellectual disabilities. Gene-driven phenotype examination can also reveal clinically significant unsuspected condition. 相似文献64.
Optimization of Banana Juice Fermentation for the Production of Microbial Oil 总被引:4,自引:0,他引:4 下载免费PDF全文
Apiotrichum curvatum ATCC 20509 (formerly Candida curvata D), a lipid-accumulating yeast, was grown in banana juice. The optimum conditions for biomass production in shake flasks were 30°C growth temperature, efficient aeration, a juice concentration of 25%, and preliminary heat treatment at less than sterilization conditions. Under controlled conditions in a fermentor, 20% banana juice was optimum. High concentrations of yeast extract (0.3%) increased biomass production by 40% but decreased oil production by 30%. A lower yeast extract concentration (0.05%) increased biomass production by 2% and oil production by 25%. The best growth and oil production were observed when asparagine (1.4 g/liter) and mineral salts were added to the banana juice. The addition of minerals seemed to improve the utilization of carbon. Growth inhibition was observed when the fermentor was aerated with pure oxygen, even when additional nutrients were present. A fed-batch process permitted the juice concentration to be increased from 15 to 82%; biomass accumulation was three times higher than in batch fermentations. However, the cellular lipid content was only 30% of dry weight, and chemical oxygen demand reduction was slow and inefficient. 相似文献
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Marlys Hammond David G. Washburn Tram H. Hoang Sharada Manns James S. Frazee Hiroko Nakamura Jaclyn R. Patterson Walter Trizna Charlene Wu Leonard M. Azzarano Rakesh Nagilla Melanie Nord Rebecca Trejo Martha S. Head Baoguang Zhao Angela M. Smallwood Kendra Hightower Nicholas J. Laping Christine G. Schnackenberg Scott K. Thompson 《Bioorganic & medicinal chemistry letters》2009,19(15):4441-4445
The lead serum and glucocorticoid-related kinase 1 (SGK1) inhibitors 4-(5-phenyl-1H-pyrrolo[2,3-b]pyridin-3-yl)benzoic acid (1) and {4-[5-(2-naphthalenyl)-1H-pyrrolo[2,3-b]pyridin-3-yl]phenyl}acetic acid (2) suffer from low DNAUC values in rat, due in part to formation and excretion of glucuronic acid conjugates. These PK/glucuronidation issues were addressed either by incorporating a substituent on the 3-phenyl ring ortho to the key carboxylate functionality of 1 or by substituting on the group in between the carboxylate and phenyl ring of 2. Three of these analogs have been identified as having good SGK1 inhibition potency and have DNAUC values suitable for in vivo testing. 相似文献
69.
Roth DM Lai NC Gao MH Drumm JD Jimenez J Feramisco JR Hammond HK 《American journal of physiology. Heart and circulatory physiology》2004,287(1):H172-H177
We performed indirect intracoronary delivery of adenovirus vectors in mice and explored techniques including hypothermia and pharmacological means to increase cardiac gene transfer. Mice were maintained in a normothermic state or cooled to 25 degrees C. The aorta or both the pulmonary artery and aorta were clamped while a needle was advanced into the left ventricular cavity to deliver adenovirus vectors encoding enhanced green fluorescent protein (EGFP) or murine adenylyl cyclase type VI (AC(VI)) with saline, sodium nitroprusside, acetylcholine, or serotonin. Clamping was maintained for 30 s (normothermia) or 2 min (25 degrees C) after adenovirus administration. Mice were killed 7 or 21 days later, and hearts were examined for EGFP expression. Compared with clamping the aorta alone and with no cooling, gene transfer was increased as follows: 1) 1.3-fold with hypothermia to extend dwell time; 2) 4.5-fold by clamping the aorta and the pulmonary artery; 3) 11.4-fold with nitroprusside administration; 4) 11.8-fold with serotonin addition, and 5) 14.3-fold with acetylcholine delivery. Gene expression remained substantial at 21 days, and no significant inflammatory response was seen. Efficacy of the method was tested by performing gene transfer of adenovirus encoding AC(VI). Fourteen days after gene transfer, hearts isolated from mice that received adenovirus encoding AC(VI) showed increased contractile function. Indirect intracoronary delivery of adenovirus vectors in mice is associated with efficient cardiac gene transfer and increased left ventricular function after AC(VI) gene transfer. 相似文献
70.
Chappell MA Hammond KA 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2004,174(1):41-48
In nature, animals frequently need to deal with several physiological challenges simultaneously. We examined thermoregulatory performance (body temperature stability) and maximal oxygen consumption of deer mice (Peromyscus maniculatus) during intense exercise at room temperature, acute cold exposure, and exercise during cold exposure. Results with exercise and cold exposure alone were consistent with previous studies: there was little difference between maximal metabolism elicited by exercise alone or cold exposure alone in warm-acclimated mice; after cold acclimation (9 weeks at 5 °C), maximal exercise metabolism did not change but maximum thermogenic capacity increased by >60%. Warm acclimated animals did not increase maximal oxygen consumption when exercise was combined with moderate cold (0 °C) and had decreased maximal oxygen consumption when exercise was combined with severe cold (–16 °C). Combined cold and exercise also decreased thermoregulatory performance and exercise endurance time. Cold acclimation improved thermoregulatory performance in combined cold and exercise, and there was also a slight increase in endurance. However, as for warm-acclimated animals, maximal exercise metabolism did not increase at low temperatures. We interpret these results as an indication of competition between thermoregulatory and locomotor effectors (brown adipose tissue and skeletal muscle) under the combined challenges of cold exposure and maximal exercise, with priority given to the locomotor function.Abbreviations
BAT
brown adipose tissue
-
T
b
body temperature
-
O
2
rate of oxygen consumption
-
O
2
max
maximal O2 in exercise
-
O
2
sum
maximal O2 during cold exposure
Communicated by G. Heldmaier 相似文献