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1.
We have evaluated codon usage bias in Drosophila histone genes and have obtained the nucleotide sequence of a 5,161-bp D. hydei histone gene repeat unit. This repeat contains genes for all five histone proteins (H1, H2a, H2b, H3, and H4) and differs from the previously reported one by a second EcoRI site. These D. hydei repeats have been aligned to each other and to the 5.0-kb (i.e., long) and 4.8-kb (i.e., short) histone repeat types from D. melanogaster. In each species, base composition at synonymous sites is similar to the average genomic composition and approaches that in the small intergenic spacers of the histone gene repeats. Accumulation of synonymous changes at synonymous sites after the species diverged is quite high. Both of these features are consistent with the relatively low codon usage bias observed in these genes when compared with other Drosophila genes. Thus, the generalization that abundantly expressed genes in Drosophila have high codon bias and low rates of silent substitution does not hold for the histone genes.   相似文献   
2.
The study aimed to explore the suicidal process, suicidal communication and psychosocial situation of young suicide attempters in a rural community in Hanoi, Vietnam. Semi-structured interviews were conducted, in a community setting, with 19 suicide attempters aged 15-24 who had been consecutively hospitalized in an intensive care unit. In 12 of 19 cases, the first pressing, distinct and constant suicidal thoughts appeared less than one day before the suicide attempt in question. However, distress and mild, fleeting suicidal thoughts had been present up to six months before the suicide attempt in 16 cases. Five respondents had a suicide plan one to three days before attempting suicide. Altogether, 13 engaged in some form of suicidal communication before their attempt. This communication was, however, difficult for outsiders to interpret. Twelve of the respondents were victims of regular physical abuse and 16 had suffered psychological violence for at least one year before attempting suicide. Eighteen of the respondents used pesticides or raticides in their suicide attempts. None sought advice or consultation in the community despite long-standing psychosocial problems. The strategy of reducing the availability of suicide means (e.g., pesticides or raticides) in Asian countries should be complemented with a long-term suicide-preventive strategy that targets school dropouts and domestic violence, and promotes coping abilities and communication about psychological and social problems as well as recognition of signs of distress and suicidal communication.  相似文献   
3.
The isolation and characterization of fungal strains from poorly described taxa allows undercover attributes of their basic biology useful for biotechnology. Here, a wild fungal strain (CMU‐196) from recently described Paraconiothyrium genus was analyzed. CMU‐196 was identified as Paraconiothyrium brasiliense by phylogenetic analysis of the rDNA internal transcribed spacer region (ITS). CMU‐196 metabolized 57 out of 95 substrates of the Biolog FF microplates. Efficient assimilation of dextrins and glycogen indicates that CMU‐196 is a good producer of amylolytic enzymes. It showed a remarkably assimilation of α‐d ‐lactose, substrate described as inducer of cellulolytic activity but poorly assimilated by several fungi. Metabolically active mycelium of the strain decolorized broth supplemented with direct blue 71, Chicago sky blue and remazol brilliant blue R dyes. The former two dyes were also well removed from broth by mycelium inactivated by autoclaving. Both mycelia had low efficiency for removing fuchsin acid from broth and for decolorizing wastewater from the paper industry. CMU‐196 strain showed extracellular laccase activity when potato dextrose broth was supplemented with Cu+2, reaching a maximum activity of 46.8 (±0.33) U L?1. Studied strain antagonized phytopathogenic Colletotrichum spp. fungi and Phytophthora spp. oomycetes in vitro, but is less effective towards Fusarium spp. fungi. CMU‐196 antagonism includes overgrowing the mycelia of phytopathogens and growth inhibition, probably by hydrosoluble extracellular metabolites. The biotechnological potential of strain CMU‐196 here described warrants further studies to have a more detailed knowledge of the mechanisms associated with its metabolic versatility, capacity for environmental detoxification, extracellular laccase production, and antagonism against phytopathogens. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:846–857, 2018  相似文献   
4.
There is a need for safe medications that can effectively support recovery by treating symptoms of protracted abstinence that may precipitate relapse in alcoholics, e.g. craving and disturbances in sleep and mood. This proof-of-concept study reports on the effectiveness of gabapentin 1200 mg for attenuating these symptoms in a non-treatment-seeking sample of cue-reactive, alcohol-dependent individuals. Subjects were 33 paid volunteers with current Diagnostic and Statistical Manual of Mental Disorders-IV alcohol dependence and a strength of craving rating 1 SD or greater for alcohol than water cues. Subjects were randomly assigned to gabapentin or placebo for 1 week and then participated in a within-subjects trial where each was exposed to standardized sets of pleasant, neutral and unpleasant visual stimuli followed by alcohol or water cues. Gabapentin was associated with significantly greater reductions than placebo on several measures of subjective craving for alcohol as well as for affectively evoked craving. Gabapentin was also associated with significant improvement on several measures of sleep quality. Side effects were minimal, and gabapentin effects were not found to resemble any major classes of abused drugs. Results suggest that gabapentin may be effective for treating the protracted abstinence phase in alcohol dependence and that a randomized clinical trial would be an appropriate next step. The study also suggests the value of cue-reactivity studies as proof-of-concept screens for potential antirelapse drugs.  相似文献   
5.
Multiple factors determine plant reproductive success and their influence may vary spatially. This study addresses several factors influencing female reproductive success in three populations of Ruellia nudiflora, specifically we: (i) determine if fruit set is pollen‐limited and if pollinator visitation rates are related to this condition; (ii) estimate fruit set via autonomous self‐pollination (AS) and relate it to the magnitude of herkogamy; and (iii) evaluate if fruit abortion is a post‐pollination mechanism that determines the magnitude of pollen limitation. At each site we marked 35 plants, grouped as: unmanipulated control (C) plants subjected to open pollination, plants manually cross‐pollinated (MP), and plants excluded from pollinators and only able to self‐pollinate autonomously (AS). Fruit set was greater for MP relative to C plants providing evidence for pollen limitation, while a tendency was observed for lower fruit abortion of MP relative to C plants suggesting that fruit set is influenced not only by pollen delivery per se, but also by subsequent abortion. In addition, although pollinator visits varied significantly among populations, the magnitude of pollen limitation did not, suggesting that pollinator activity was not relevant in determining pollen limitation. Finally, fruit set tended to decrease with the degree of herkogamy for AS plants, but this result was inconclusive. These findings have contributed to identify which factors influence reproductive success in populations of R. nudiflora, with potentially relevant implications for population genetic structure and mating system evolution of this species.  相似文献   
6.
A recently silenced, duplicate PgiC locus in Clarkia   总被引:1,自引:0,他引:1  
Previous electrophoretic analysis showed that 17 diploid species of the wildflower Clarkia (Onagraceae) have two cytosolic isozymes of phosphoglucose isomerase (PGIC; EC 5.3.1.9), whereas 15 other diploid species have a single PGIC. Molecular studies revealed that the two isozymes in the former species are encoded by duplicate genes, PgiC1 and PgiC2, whereas the single isozyme in the latter is always encoded by PgiC1. Phylogenetic analysis of the nucleotide sequences implied that PgiC2 was silenced four times independently in the genus. Here we describe a psi PgiC2 from C. mildrediae, a species in which only PgiC1 is expressed. The discovery of the psi PgiC2 is significant because it confirms a formal prediction of the phylogenetic analysis. The psi PgiC2 includes 5,039 nucleotides corresponding to 18 of the 23 exons of PgiC, as well as the intervening introns and 3' nontranslated region. The absence of an increase of nucleotide substitutions in its "exons" suggests that the gene was silenced recently. The present study appears to be the first to establish that a specific duplicate gene locus regularly expressed in a group of related plant species has been silenced in one of them. The multiple independent silencings of PgiC2 suggest that it remained functional but inessential in ancestral lineages. We discuss the possibility that PgiC2 may have been preserved in these lineages by selection against mutants causing defective PGIC1- PGIC2 heterodimers.   相似文献   
7.
The effects of ovariectomy and exogenous androgen administration on the indole and porphyrin metabolism of Syrian hamster Harderian glands were studied. Ovariectomy alone had no effect on any of the parameters analyzed. The administration of either testosterone or 5 alpha-dihydrotestosterone increased the activity of N-acetyltransferase in the Harderian glands. However, androgen treatment failed to change the activity of hydroxyindole-O-methyltransferase. Melatonin content of the glands dropped 20 days after treatment with testosterone and 10 days after the administration of 5 alpha-dihydrotestosterone. The porphyrin content of the Harderian glands was dramatically depressed after the administration of either androgen. It is concluded that the Harderian glands of Syrian hamsters are under an androgenic control involving 5 alpha-dihydrotestosterone.  相似文献   
8.
Homologies in Cambrian Onychophora   总被引:4,自引:0,他引:4  
Marine animals related to Recent onychophorans form a significant component in Cambrian faunas. Twelve characters are analysed for homologies in the seven best known Cambrian onychophorans. New morphological evidence and homology analyses for several characters indicate an anteroposterior reversal of Hallucigenia and Microdictyon . Proposed expansion of the trunk in Microdietyon during compaction is rejected. A jaw is tentatively identified in Onychodictyon . The shape of the annulations and the disposition of the tenth leg pair in Aysheaia are reinterpreted, and the suggestion of two somites to the first appendage pair is rejected. A suggested morphocline may mirror the phylogeny of the group. The taxonomic confusion surrounding the supposed radiolarian family Eoconchariidae is cleared  相似文献   
9.
The Illumina BovineLD BeadChip was designed to support imputation to higher density genotypes in dairy and beef breeds by including single-nucleotide polymorphisms (SNPs) that had a high minor allele frequency as well as uniform spacing across the genome except at the ends of the chromosome where densities were increased. The chip also includes SNPs on the Y chromosome and mitochondrial DNA loci that are useful for determining subspecies classification and certain paternal and maternal breed lineages. The total number of SNPs was 6,909. Accuracy of imputation to Illumina BovineSNP50 genotypes using the BovineLD chip was over 97% for most dairy and beef populations. The BovineLD imputations were about 3 percentage points more accurate than those from the Illumina GoldenGate Bovine3K BeadChip across multiple populations. The improvement was greatest when neither parent was genotyped. The minor allele frequencies were similar across taurine beef and dairy breeds as was the proportion of SNPs that were polymorphic. The new BovineLD chip should facilitate low-cost genomic selection in taurine beef and dairy cattle.  相似文献   
10.
To achieve the integration of biological data available on the World Wide Web and maintained in diverse sources such as GDB, Genbank or Acedb, we have developed a software called Jade. Jade allows programmers to create analytic tools and graphical user interfaces for one or more existing bioinformatics data sources. These tools can then be interchanged, compared and reused without making modifications in the data sources themselves. The system is implemented in the Java programming language and will run equally well on Macintosh, Windows or Unix workstations. Jade is free and can be used immediately by all interested parties.  相似文献   
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