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1.
DNA sequence data were collected and screened for single nucleotide polymorphisms (SNPs) in westslope cutthroat trout (Oncorhynchus clarki lewisi) and also for substitutions that could be used to genetically discriminate rainbow trout (O. mykiss) and cutthroat trout, as well as several cutthroat trout subspecies. In total, 260 expressed sequence tag‐derived loci were sequenced and allelic discrimination genotyping assays developed from 217 of the variable sites. Another 50 putative SNPs in westslope cutthroat trout were identified by restriction‐site‐associated DNA sequencing, and seven of these were developed into assays. Twelve O. mykiss SNP assays that were variable within westslope cutthroat trout and 12 previously published SNP assays were also included in downstream testing. A total of 241 assays were tested on six westslope cutthroat trout populations (N = 32 per population), as well as collections of four other cutthroat trout subspecies and a population of rainbow trout. All assays were evaluated for reliability and deviation from Hardy–Weinberg and linkage equilibria. Poorly performing and duplicate assays were removed from the data set, and the remaining 200 assays were used in tests of population differentiation. The remaining markers easily distinguished the various subspecies tested, as evidenced by mean GST of 0.74. A smaller subset of the markers (N = 86; average GST = 0.40) was useful for distinguishing the six populations of westslope cutthroat trout. This study increases by an order of magnitude the number of genetic markers available for the study of westslope cutthroat trout and closely related taxa and includes many markers in genes (developed from ESTs).  相似文献   

2.
Microbial exposure may direct the immune system away from allergic-type responses, but until now probiotic interventions have had limited success in the prevention and treatment of allergic diseases. In this study, a novel probiotic mixture was specifically created based on preliminary in vitro investigations on pollen-induced immune responses. A mixture with Lactobacillus rhamnosus GR-1 and a novel fecal Bifidobacterium adolescentis isolate was formulated into a yogurt and tested for its effects in 36 subjects with allergic rhinitis over 2 pollen seasons in a double-blind, placebo-controlled trial. The new formulation was well tolerated, but did not have significant effects on the quality of life scores, use of antihistamines, or eosinophil cationic protein concentration in nasal lavage. However, at the end of the grass pollen season, serum IL-10 and IL-12 levels were increased in the probiotic group compared to the controls. During the ragweed season, the serum TGF-β levels were significantly higher in the probiotic group than in the controls. In conclusion, the novel probiotic formulation had potentially desirable effects on the cytokine profile of patients with allergic rhinitis, but provided few clinical benefits. The study highlights the challenges in designing efficient immunomodulatory probiotic therapies based upon in vitro findings.  相似文献   

3.
The use of drug-antibody conjugates affords a method for the targeted delivery of anticancer drugs specifically to cancer cells. Monoclonal antibodies alone usually do not possess high therapeutic efficacy, however, they are capable of targeting tumor markers selectively. We have prepared taxoids with significantly higher cytotoxicity than paclitaxel and docetaxel. These taxoids now meet the high potency required for use in a targeted-delivery approach using monoclonal antibodies. The synthesis and biological evaluation of these taxoids are reported.  相似文献   

4.
Aim Invasive species frequently exhibit high temporal and spatial variation in abundance. Although ecological aspects undoubtedly affect this variation, genetic factors may also play a part. The invasive unicolonial yellow crazy ant Anoplolepis gracilipes exhibits considerable variation in abundance throughout its extensive distribution in Australia’s Northern Territory, where it was first detected in the 1980s. First, we aimed to determine whether A. gracilipes variation in abundance was associated with behavioural and genetic differentiation of the population and to determine whether one or more introductions occurred. Second, we investigated whether the A. gracilipes population was genetically and behaviourally heterogeneous to determine whether population divergence has occurred since introduction. Location Tropical monsoonal savanna in Arnhem Land, Northern Territory, Australia. Methods Ant abundances were assessed at 13 sites throughout the study region. We used mitochondrial DNA sequences and microsatellite molecular markers to determine population genetic structure, which we correlated with abundance. Behavioural differentiation was assayed using aggression trials and analysed together with genetic data to investigate population divergence. Results Although we found considerable variation in abundance, we found no association between population structure and differences in abundance. Our analyses suggest that A. gracilipes ants in Arnhem Land resulted from a single introduction. The population is not homogeneous, however, as aggression scores varied over both genetic and geographic distance. We also found a positive relationship between genetic and geographic distance. Main conclusions The variation in abundance in the Arnhem Land population of A. gracilipes is clearly not owing to invasion by ants from different sources. The genetic and behavioural differentiation we observed is suggestive of incipient genetic and behavioural divergence, which may be expected over time when an invasive species enters in a new environment.  相似文献   

5.
6.

Background

The suppression of amber stop codons with non-canonical amino acids (ncAAs) is used for the site-specific introduction of many unusual functions into proteins. Specific orthogonal aminoacyl-tRNA synthetase (o-aaRS)/amber suppressor tRNACUA pairs (o-pairs) for the incorporation of ncAAs in S. cerevisiae were previously selected from an E. coli tyrosyl-tRNA synthetase/tRNACUA mutant library. Incorporation fidelity relies on the specificity of the o-aaRSs for their ncAAs and the ability to effectively discriminate against their natural substrate Tyr or any other canonical amino acid.

Methodology/Principal Findings

We used o-pairs previously developed for ncAAs carrying reactive alkyne-, azido-, or photocrosslinker side chains to suppress an amber mutant of human superoxide dismutase 1 in S. cerevisiae. We found worse incorporation efficiencies of the alkyne- and the photocrosslinker ncAAs than reported earlier. In our hands, amber suppression with the ncAA containing the azido group did not occur at all. In addition to the incorporation experiments in S. cerevisiae, we analyzed the catalytic properties of the o-aaRSs in vitro. Surprisingly, all o-aaRSs showed much higher preference for their natural substrate Tyr than for any of the tested ncAAs. While it is unclear why efficiently recognized Tyr is not inserted at amber codons, we speculate that metabolically inert ncAAs accumulate in the cell, and for this reason they are incorporated despite being weak substrates for the o-aaRSs.

Conclusions/Significance

O-pairs have been developed for a whole plethora of ncAAs. However, a systematic and detailed analysis of their catalytic properties is still missing. Our study provides a comprehensive scrutiny of o-pairs developed for the site-specific incorporation of reactive ncAAs in S. cerevisiae. It suggests that future development of o-pairs as efficient biotechnological tools will greatly benefit from sound characterization in vivo and in vitro in parallel to monitoring intracellular ncAA levels.  相似文献   

7.
In this study, we synthesized a new congener series of N-sulphonylhydrazones designed as candidate ROCK inhibitors using the molecular hybridization of the clinically approved drug fasudil (1) and the IKK-β inhibitor LASSBio-1524 (2). Among the synthesized compounds, the N-methylated derivative 11 (LASSBio-2065) showed the best inhibitory profile for both ROCK isoforms, with IC50 values of 3.1 and 3.8?µM for ROCK1 and ROCK2, respectively. Moreover, these compounds were also active in the scratch assay performed in human breast cancer MDA-MB 231 cells and did not display toxicity in MTT and LDH assays. Molecular modelling studies provided insights into the possible binding modes of these N-sulphonylhydrazones, which present a new molecular architecture capable of being optimized and developed as therapeutically useful ROCK inhibitors.  相似文献   

8.
A series of novel 1H- and 2H-indazole derivatives of the commercially available dehydroepiandrosterone acetate have been synthesized and tested for inhibition of human cytochrome 17alpha-hydroxylase-C(17,20)-lyase (CYP17), androgen receptor (AR) binding affinity, and cytotoxic potential against three prostate cancer (PC) cell lines.  相似文献   

9.
Successful conservation and management of rare and elusive species requires reliable estimates of population size, but acquisition of such data is often challenging. We compare the two most frequently used methods of assessing abundance of Eurasian otter (Lutra lutra) populations, noninvasive genetic sampling (NGS) based on genotyping of faeces and field surveys using snow tracking. In a 100-km2 oligotrophic otter habitat with linear water bodies, both methods yielded very similar estimates (10–12 individuals). However, in a 100-km2 fishpond area, consisting of a complex network of rivers, fishponds, channels and marshes, genotyping of faeces revealed the presence of a higher number of individuals (46–50 genotypes) than the snow survey (38 individuals). NGS data analysed by capture-mark-recapture (CMR)-based software CAPWIRE provided even higher estimates, being twice the number assessed through snow tracking (76–81 individuals, CI95% = 49–96 and 55–89). Our results suggest that the performance of both NGS and snow tracking is comparable in simple linear habitats, but in complex habitats with very high otter density a combination of genetic and field methods, or CMR analysis using genetic data, is recommended. We emphasise that to obtain reliable estimates using NGS it is necessary to follow strict protocols for detection and elimination of genotyping errors. Based on a literature review and our experience, we suggest improvements that may increase the success rate and efficiency of NGS for otters.  相似文献   

10.
11.
Declines in shark populations worldwide are of particular concern to fishery managers and conservation biologists. Molecular-based technologies provide an efficient means to collect basic life-history information and estimates of dispersal that are critical to management. A novel method for obtaining high quality mtDNA from shark jaws and teeth for shark population genetic studies is described.  相似文献   

12.
13.
In this paper, we report the synthesis and pharmacological evaluation of pyrazine N-acylhydrazone (NAH) derivatives (2as) designed as novel analgesic and anti-inflammatory drug candidates. This series was planned by molecular simplification of prototype 1 (LASSBio-1018), previously described as a non-selective cyclooxygenase inhibitor. Derivatives 2as were evaluated in several animal models of pain and inflammation, standing-out compound 2o (2-N′-[(E)-(3,4,5-trimethoxyphenyl) methylidene]-2-pyrazinecarbohydrazide; LASSBio-1181), that was also active in a murine model of chronic inflammation (i.e., adjuvant-induced arthritis test in rats) and can be considered a new analgesic and anti-inflammatory lead for drug development.  相似文献   

14.
Population size information is critical for managing endangered or harvested populations. Population size can now be estimated from non-invasive genetic sampling. However, pitfalls remain such as genotyping errors (allele dropout and false alleles at microsatellite loci). To evaluate the feasibility of non-invasive sampling (e.g., for population size estimation), a pilot study is required. Here, we present a pilot study consisting of (i) a genetic step to test loci amplification and to estimate allele frequencies and genotyping error rates when using faecal DNA, and (ii) a simulation step to quantify and minimise the effects of errors on estimates of population size. The pilot study was conducted on a population of red deer in a fenced natural area of 5440 ha, in France. Twelve microsatellite loci were tested for amplification and genotyping errors. The genotyping error rates for microsatellite loci were 0–0.83 (mean=0.2) for allele dropout rates and 0–0.14 (mean=0.02) for false allele rates, comparable to rates encountered in other non-invasive studies. Simulation results suggest we must conduct 6 PCR amplifications per sample (per locus) to achieve approximately 97% correct genotypes. The 3% error rate appears to have little influence on the accuracy and precision of population size estimation. This paper illustrates the importance of conducting a pilot study (including genotyping and simulations) when using non-invasive sampling to study threatened or managed populations.  相似文献   

15.
16.
Genetic counseling and testing for heritable susceptibility to breast cancer caused by mutations in BRCA genes are largely unavailable to underserved women in the United States. Starting in 2002 the UCSF Cancer Risk Program offered this service free of charge to poor and medically indigent women at San Francisco General Hospital (SFGH). One recruitment strategy was a single-page questionnaire in four languages administered to women waiting for mammograms at SFGH. This report analyzes our first 3 years of experience with the recruitment questionnaire and compares the patient demographics and BRCA test results at SFGH with a more typical population undergoing genetic counseling and testing at UCSF's Mt. Zion Hospital (MZH). To our knowledge this is the first comprehensive clinical service for hereditary breast cancer in a U.S. public hospital. The ethnic mix of all 350 patients counseled was Caucasian 49% (approximately 20% of Caucasians reported Ashkenazi Jewish ancestry), Latina, 26%; African American, 13%; and Asian/other, 12%. Compared to the MZH population, SFGH patients were more ethnically diverse, less educated and more likely to be unemployed. Of 72 patients tested for BRCA mutations, 51 (71%) were negative, 5 were BRCA1 positive, and 12 were BRCA2 positive. Four (1 Caucasian, 1 Latina, 2 African American) had a total of 13 BRCA variants of unknown significance (VUS). The ratio of BRCA1/BRCA2 positive SFGH patients (5/12) was reversed compared to MZH (119/91). We evaluated 4573 recruitment questionnaires and 280 (6%) were judged to represent a high risk of heritable cancer. After additional screening and referral negotiation, 74 were scheduled for counseling. We judged the recruitment questionnaire to be a feasible, efficient, and reasonably cost-effective way to identify women at high risk of hereditary cancer in a traditionally underserved population. Underserved populations present special challenges for genetic counselors because of large, geographically dispersed families, cultural taboos about cancer diagnoses, and social marginalization. Despite these complexities, the clinical service at SFGH has been well accepted by patients and staff. Our successful venture can serve as a model for other public hospitals contemplating this clinical service.  相似文献   

17.
Modifications in a zoo exhibit were made to increase the arboreality of an aged female diana monkey, and to increase her use of the central portion of the exhibit where a new food shelf had been added. Branches, which formed ramps to this shelf, also were added. Following these changes, the aged female's arboreality increased slightly, and her use of the central portion of the exhibit increased significantly. Changes in habitat use following these modifications also were noted in the other two diana monkeys in the group. These results suggest that zoo habitats can be made more usable for individuals whose behavioral capabilities might be limited due to age or physical disability.  相似文献   

18.
19.
《Genomics》2023,115(3):110620
To assist in forensic DNA investigation, we developed a new panel capable of simultaneously amplifying 56 ancestry-informative InDels, three Y-InDels and the Amelogenin locus in one PCR reaction. The fragment lengths of the InDel amplicons in this panel were restricted to <200 bp to benefit degraded DNA analysis. In this study, we explored the efficiency of this new panel for forensic applications in the Han Chinese population, and further shed light on the genetic structures of Han populations. We showed that the new panel could be served as an efficient tool for ancestry inference of intercontinental populations. Especially, the Han individuals in different regions could be 100% correctly predicted to be of East Asian origin with this new panel. The Han populations in different regions shared similar ancestry components in their genetic structures. Besides, we also revealed that the new panle could be useful for individual identification in different Han Chinese populations. In conclusion, we have provided the necessary evidence that the self-constructed new panel could play an important role in forensic DNA investigation.  相似文献   

20.
Self-incompatibility in the Solanaceae is mediated by S-RNase alleles expressed in the style, which confer specificity for pollen recognition. Nicotiana alata has been successfully used as an experimental model to elucidate cellular and molecular aspects of S-RNase-based self-incompatibility in Solanaceae. However, S-RNase alleles of this species have not been surveyed from natural populations and consequently the S-haplotype diversity is poorly known. Here the molecular and functional characterization of seven S-RNase candidate sequences, identified from a natural population of N. alata, are reported. Six of these candidates, S 5 , S 27 , S 70 , S 75 , S 107 , and S 210 , showed plant-specific amplification in the natural population and style-specific expression, which increased gradually during bud maturation, consistent with the reported S-RNase expression. In contrast, the S 63 ribonuclease was present in all plants examined and was ubiquitously expressed in different organs and bud developmental stages. Genetic segregation analysis demonstrated that S 27 , S 70 , S 75 , S 107 , and S 210 alleles were fully functional novel S-RNases, while S 5 and S 63 resulted to be non-S-RNases, although with a clearly distinct pattern of expression. These results reveal the importance of performing functional analysis in studies of S-RNase allelic diversity. Comparative phylogenetic analysis of six species of Solanaceae showed that N. alata S-RNases were included in eight transgeneric S-lineages. Phylogenetic pattern obtained from the inclusion of the novel S-RNase alleles confirms that N. alata represents a broad sample of the allelic variation at the S-locus of the Solanaceae.  相似文献   

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