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51.
A molecular and evolutionary study of the beta-globin gene family of the Australian marsupial Sminthopsis crassicaudata 总被引:1,自引:0,他引:1
Cooper SJ; Murphy R; Dolman G; Hussey D; Hope RM 《Molecular biology and evolution》1996,13(7):1012-1022
Beta-globin gene families in eutherians (placental mammals) consist of a
set of four or more developmentally regulated genes which are closely
linked and, in general, arranged in the order 5'-embryonic/fetal genes-
adult genes-3'. This cluster of genes is proposed to have arisen by tandem
duplication of ancestral beta-globin genes, with the first duplication
occurring 200 to 155 MYBP just prior to a period in mammalian evolution
when eutherians and marsupials diverged from a common ancestor. In this
paper we trace the evolutionary history of the beta-globin gene family back
to the origins of these mammals by molecular characterization of the
beta-globin gene family of the Australian marsupial Sminthopsis
crassicaudata. Using Southern and restriction analysis of total genomic DNA
and bacteriophage clones of beta-like globin genes, we provide evidence
that just two functional beta-like globin genes exist in this marsupial,
including one embryonic- expressed gene (S.c-epsilon) and one
adult-expressed gene (S.c-beta), linked in the order 5'-epsilon-beta-3'.
The entire DNA sequence of the adult beta-globin gene is reported and shown
to be orthologous to the adult beta-globin genes of the North American
marsupial Didelphis virginiana and eutherian mammals. These results,
together with results from a phylogenetic analysis of mammalian beta-like
globin genes, confirm the hypothesis that a two-gene cluster, containing an
embryonic- and an adult-expressed beta-like globin gene, existed in the
most recent common ancester of marsupials and eutherians. Northern analysis
of total RNA isolated from embryos and neonatals indicates that a switch
from embryonic to adult gene expression occurs at the time of birth,
coinciding with the transfer of the marsupial from a uterus to a pouch
environment.
相似文献
52.
Mohammad?Abass?AhangerEmail author Megha?Tittal Rayees?Ahmad?Mir RM?Agarwal 《Protoplasma》2017,254(5):1953-1963
Present communication reports laboratory and pot experiments conducted to study the influence of water and osmotic stress on nitrogen uptake and metabolism in two wheat (Triticum aestivum L) cultivars with and without potassium supplementation. Polyethylene glycol 6000-induced osmotic stress/restricted irrigation caused a considerable decline in the activity of nitrate reductase, glutamate synthase, alanine and aspartate aminotransferases, and glutamate dehydrogenase. Potassium considerably improved nitrogen metabolism under normal water supply conditions and also resulted in amelioration of the negative impact of water and osmotic stresses indicating that potassium supplementation can be used as a potential tool for enhancing the nitrogen use efficiency in wheat for exploiting its genetic potential. 相似文献
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54.
J. E. Williamson R. M. Huebinger J. A. Sommer E. E. Louis R. C. Barber 《Molecular ecology resources》2002,2(2):110-112
Eighteen polymorphic microsatellite loci from the highly endangered Sumatran tiger (Panthera tigris sumatrae) were isolated and characterized. Upon polymerase chain reaction amplification, 16 of these markers produced a single, sharp band in all three tiger and 10 non‐tiger felid species examined. Of the two remaining loci, 6HDZ057 and 6HDZ635 failed to amplify genomic DNA from puma (Felis concolor) and cheetah (Acinonyx jubatus), respectively. The amplification of these markers across four genera is an indication of their usefulness for population genetics studies and conservation work in a wide range of felid species. 相似文献
55.
Ryan M. Huebinger Donna J. Pierson Thomas W. De Maar David M. Brown Rick A. Brenneman Edward E. Louis 《Molecular ecology resources》2002,2(4):531-533
Sixteen polymorphic microsatellite markers with an average allele size of k = 4.3 are identified from a genomic plasmid library constructed for giraffe (Giraffa camelopardalis ssp.). Primer sequences and marker data are reported in tabular form. The markers were screened in a population of 25 Maasai giraffe (G. c. tippelskirchi) collected near the Athi River, Kenya. The average observed heterozygosity for each marker was 0.36 with an average expected heterozygosity of 0.535. Hardy–Weinberg deviations are reported from this population, which is suspected to be inbred. The markers will be used to screen the captive giraffe population for subspecific or hybrid classification. 相似文献
56.
With the cancellation of fenamiphos in the near future, alternative nematode management tactics for plant-parasitic nematodes (PPN) on golf courses need to be identified. The use of entomopathogenic nematodes (EPN) has been suggested as one possible alternative. This paper presents the results of 10 experiments evaluating the efficacy of EPN at managing PPN on turfgrasses and improving turf performance. These experiments were conducted at various locations throughout Florida over the course of a decade. In different experiments, different EPN species were tested against different species of PPN. Separate experiments evaluated multiple rates and applications of EPN, compared different EPN species, and compared single EPN species against multiple species of PPN. In a few trials, EPN were associated with reductions in certain plant-parasite species, but in other trials were associated with increases. In most trials, EPN had no effect on plant parasites. Because EPN were so inconsistent in their results, we conclude that EPN are not acceptable alternatives to fenamiphos by most turf managers in Florida at this time. 相似文献
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58.
Kjellman BM Fredrikson M Glad-Mattsson G Sjöberg F Huss FR 《Annals of surgical innovation and research》2011,5(1):4-8
Background
Hypothermia in burns is common and increases morbidity and mortality. Several methods are available to reach and maintain normal core body temperature, but have not yet been evaluated in critical care for burned patients. Our unit's ordinary technique for controlling body temperature (Bair Hugger®+ radiator ceiling + bed warmer + Hotline®) has many drawbacks e.g.; slow and the working environment is hampered. The aim of this study was to compare our ordinary heating technique with newly-developed methods: the Allon?2001 Thermowrap (a temperature regulating water-mattress), and Warmcloud (a temperature regulating air-mattress).Methods
Ten consecutive burned patients (> 20% total burned surface area and a core temperature < 36.0°C) were included in this prospective, randomised, comparative study. Patients were randomly exposed to 3 heating methods. Each treatment/measuring-cycle lasted for 6 hours. Each heating method was assessed for 2 hours according to a randomised timetable. Core temperature was measured using an indwelling (bladder) thermistor. Paired t-tests were used to assess the significance of differences between the treatments within the patients. ANOVA was used to assess the differences in temperature from the first to the last measurement among all treatments. Three-way ANOVA with the Tukey HSD post hoc test and a repeated measures ANOVA was used in the same manner, but included information about patients and treatment/measuring-cycles to control for potential confounding. Data are presented as mean (SD) and (range). Probabilities of less than 0.05 were accepted as significant.Results
The mean increase, 1.4 (SD 0.6°C; range 0.6-2.6°C) in core temperature/treatment/measuring-cycle highly significantly favoured the Allon?2001 Thermowrap in contrast to the conventional method 0.2 (0.6)°C (range -1.2 to 1.5°C) and the Warmcloud 0.3 (0.4)°C (range -0.4 to 0.9°C). The procedures for using the Allon?2001 Thermowrap were experienced to be more comfortable and straightforward than the conventional method or the Warmcloud.Conclusions
The Allon?2001 Thermowrap was more effective than the Warmcloud or the conventional method in controlling patients' temperatures. 相似文献59.
O'Bryant SE Xiao G Barber R Huebinger R Wilhelmsen K Edwards M Graff-Radford N Doody R Diaz-Arrastia R;Texas Alzheimer's Research & Care Consortium;Alzheimer's Disease Neuroimaging Initiative 《PloS one》2011,6(12):e28092
Context
There is no rapid and cost effective tool that can be implemented as a front-line screening tool for Alzheimer''s disease (AD) at the population level.Objective
To generate and cross-validate a blood-based screener for AD that yields acceptable accuracy across both serum and plasma.Design, Setting, Participants
Analysis of serum biomarker proteins were conducted on 197 Alzheimer''s disease (AD) participants and 199 control participants from the Texas Alzheimer''s Research Consortium (TARC) with further analysis conducted on plasma proteins from 112 AD and 52 control participants from the Alzheimer''s Disease Neuroimaging Initiative (ADNI). The full algorithm was derived from a biomarker risk score, clinical lab (glucose, triglycerides, total cholesterol, homocysteine), and demographic (age, gender, education, APOE*E4 status) data.Major Outcome Measures
Alzheimer''s disease.Results
11 proteins met our criteria and were utilized for the biomarker risk score. The random forest (RF) biomarker risk score from the TARC serum samples (training set) yielded adequate accuracy in the ADNI plasma sample (training set) (AUC = 0.70, sensitivity (SN) = 0.54 and specificity (SP) = 0.78), which was below that obtained from ADNI cerebral spinal fluid (CSF) analyses (t-tau/Aβ ratio AUC = 0.92). However, the full algorithm yielded excellent accuracy (AUC = 0.88, SN = 0.75, and SP = 0.91). The likelihood ratio of having AD based on a positive test finding (LR+) = 7.03 (SE = 1.17; 95% CI = 4.49–14.47), the likelihood ratio of not having AD based on the algorithm (LR−) = 3.55 (SE = 1.15; 2.22–5.71), and the odds ratio of AD were calculated in the ADNI cohort (OR) = 28.70 (1.55; 95% CI = 11.86–69.47).Conclusions
It is possible to create a blood-based screening algorithm that works across both serum and plasma that provides a comparable screening accuracy to that obtained from CSF analyses. 相似文献60.
One of the limitations of the use of phage antibody libraries in high throughput selections is the production of sufficient phage antibody library at the appropriate quality. Here, we successfully adapt a bioreactor-based protocol for the production of phage peptide libraries to the production of phage antibody libraries. The titers obtained in the stirred-tank bioreactor are 4 to 5 times higher than in a standard shake flask procedure, and the quality of the phage antibody library produced is indistinguishable to that produced using standard procedures as assessed by Western blotting and functional selections. Availability of this protocol will facilitate the use of phage antibody libraries in high-throughput scale selections. 相似文献