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121.
Schizophrenia and bipolar affective disorder are common, debilitating, and poorly understood and treated disorders. Both conditions are highly heritable. Recent genetic studies have suggested that the gene disrupted in schizophrenia 1 (DISC1) is an important risk factor. DISC1 seems to have a key role in building the brain and memories by interacting with other proteins, including nuclear distribution E-like protein and phosphodiesterase 4B. Here, we review the current knowledge, highlight some key unanswered questions and propose ways forward towards a better understanding of normal and abnormal brain development and function. In the long term, this might lead to the discovery of drugs that are more efficacious and safer than currently available ones.  相似文献   
122.
We evaluated attraction of cerambycid beetle species to blends of known cerambycid pheromones to determine whether such blends could be used as effective trap lures for detecting and monitoring multiple species simultaneously. Pheromone-baited traps captured 1,358 cerambycid beetles of which 1,101 (81.1%) belonged to three species in the subfamily Cerambycinae: Neoclytus acuminatus (F.), Neoclytus mucronatus (F.), and Xylotrechus colonus (F.). Beetles of these species were significantly attracted to synthetic blends that contained their pheromone components (isomers of 3-hydroxy-2-hexanone, 2,3-hexanediol, or both), despite the presence of pheromone components of different species, including other isomers of 2,3-hexanediol, (E/Z)-6,10-dimethyl-5,9-undecadien-2-yl acetate, and citral. In some cases, attraction was partially inhibited by the pheromone components of heterospecific species, whereas for N. acuminatus, attraction was completely inhibited when blends contained (2R*,3S*)-hexanediol, the racemic mixture of diastereomers of its pheromone, (2S,3S)-hexanediol. Among the remaining beetles captured were three species in the subfamily Lamiinae: Astyleiopus variegatus (Haldeman), Graphisurus fasciatus (Degeer), and Lepturges angulatus (LeConte). All three lamiine species were previously known to be attracted to (E/Z)-6,10-dimethyl-5,9-undecadien-2-yl acetate and were captured in significant numbers by blends containing that compound. Our results suggest that different types of cerambycid pheromones can be combined to create effective multispecies lures for use in surveillance programs that target exotic cerambycid species.  相似文献   
123.
The effects of Therapeutic Lifestyle Change (TLC) diets, low and high in dietary fish, on apolipoprotein metabolism were examined. Subjects were provided with a Western diet for 6 weeks, followed by 24 weeks of either of two TLC diets (10/group). Apolipoprotein kinetics were determined in the fed state using stable isotope methods and compartmental modeling at the end of each phase. Only the high-fish diet decreased median triglyceride-rich lipoprotein (TRL) apoB-100 concentration (-23%), production rate (PR, -9%), and direct catabolism (-53%), and increased TRL-to-LDL apoB-100 conversion (+39%) as compared with the baseline diet (all P < 0.05). This diet also decreased TRL apoB-48 concentration (-24%), fractional catabolic rate (FCR, -20%), and PR (-50%) as compared with the baseline diet (all P < 0.05). The high-fish and low-fish diets decreased LDL apoB-100 concentration (-9%, -23%), increased LDL apoB-100 FCR (+44%, +48%), and decreased HDL apoA-I concentration (-15%, -14%) and PR (-11%, -12%) as compared with the baseline diet (all P < 0.05). On the high-fish diet, changes in TRL apoB-100 PR were negatively correlated with changes in plasma eicosapentaenoic and docosahexaenoic acids. In conclusion, the high-fish diet decreased TRL apoB-100 and TRL apoB-48 concentrations chiefly by decreasing their PR. Both diets decreased LDL apoB-100 concentration by increasing LDL apoB-100 FCR and decreased HDL apoA-I concentration by decreasing HDL apoA-I PR.  相似文献   
124.
Grxs (glutaredoxins) are small ubiquitous redox enzymes. They are generally involved in the reduction of oxidative modifications using glutathione. Grxs are not only able to reduce protein disulfides and the low-molecular-mass antioxidant dehydroascorbate, but also represent the major enzyme class responsible for deglutathionylation reactions. Functional proteomics, including interaction studies, comparative activity measurements using heterologous proteins and structural analysis are combined to provide important insights into the crucial function of Grxs in cellular redox networks. Summarizing the current understanding of Grxs, with a special focus on organelle-localized members across species, genus and kingdom boundaries (including cyanobacteria, plants, bacteria, yeast and humans) lead to two different classifications, one according to sequence structure that gives insights into the diversification of Grxs, and another according to function within the cell that provides a basis for assessing the different roles of Grxs.  相似文献   
125.
Following PCR amplification and sequencing, nucleotide sequence alignment analyses demonstrated the presence of two kinds of 16S-23S rDNA internal spacer regions (ISRs), namely, long length ISRs of 837-844 base pair (bp) [n = six for urease-negative (UN) Campylobacter lari isolates, UN C. lari JCM2530(T), RM2100, 176, 293, 299 and 448] and short length ISRs of 679-725 bp [n = six for UN C. lari: n = 14 for urease-positive thermophilic Campylobacter (UPTC) isolates]. The analyses also indicated that the short length ISRs mainly lacked the 156 bp sequence from the nucleotide positions 122-277 bp in long length ISRs for UN C. lari JCM2530(T). The 156 bp sequences shared 94.9-96.8 % sequence similarity among six isolates. Surprisingly, atypical tRNA(Ala) gene segment (5' end 35 bp), which was extremely truncated, occurred within the 156 bp sequences in the long length ISRs, as an unexpected tRNA(Ala) pseudogene. An order of the intercistronic tRNA genes within the short nucleotide spacer of 5'-16S rDNA-tRNA(Ala)-tRNA(Ile)-23S rDNA-3' occurred in all the C. lari isolates examined.  相似文献   
126.
Multiple signalling pathways maintain human embryonic stem cells (hESC) in an undifferentiated state. Here we sought to define the significance of G protein signal transduction in the preservation of this state distinct from other cellular processes. Continuous treatment with drugs targeting G(αs)-, G(α-i/o)- and G(α-q/11)-subunit signalling mediators were assessed in independent hESC lines after 7days to discern effects on normalised alkaline phosphatase positive colony frequency vs total cell content. This identified PLCβ, intracellular free calcium and CAMKII kinase activity downstream of G(α-q/11) as of particular importance to the former. To confirm the significance of this finding we generated an agonist-responsive hESC line transgenic for a G(α-q/11) subunit-coupled receptor and demonstrated that an undifferentiated state could be promoted in the presence of an agonist without exogenously supplied bFGF and that this correlated with elevated intracellular calcium. Similarly, treatment of unmodified hESCs with a range of intracellular free calcium-modulating drugs in biologically defined mTESR culture system lacking exogenous bFGF promoted an hESC phenotype after 1week of continuous culture as defined by co-expression of OCT4 and NANOG. At least one of these drugs, lysophosphatidic acid significantly elevates phosphorylation of calmodulin and STAT3 in this culture system (p<0.05). These findings substantiate a role for G-protein and calcium signalling in undifferentiated hESC culture.  相似文献   
127.
The growth and development of plant tissues is associated with an ordered succession of cellular processes that are reflected in the appearance and disappearance of proteins. The control of the kinetics of protein turnover is central to how plants can rapidly and specifically alter protein abundance and thus molecular function in response to environmental or developmental cues. However, the processes of turnover are largely hidden during periods of apparent steady-state protein abundance, and even when proteins accumulate it is unclear whether enhanced synthesis or decreased degradation is responsible. We have used a (15)N labeling strategy with inorganic nitrogen sources coupled to a two-dimensional fluorescence difference gel electrophoresis and mass spectrometry analysis of two-dimensional IEF/SDS-PAGE gel spots to define the rate of protein synthesis (K(S)) and degradation (K(D)) of Arabidopsis cell culture proteins. Through analysis of MALDI-TOF/TOF mass spectra from 120 protein spots, we were able to quantify K(S) and K(D) for 84 proteins across six functional groups and observe over 65-fold variation in protein degradation rates. K(S) and K(D) correlate with functional roles of the proteins in the cell and the time in the cell culture cycle. This approach is based on progressive (15)N labeling that is innocuous for the plant cells and, because it can be used to target analysis of proteins through the use of specific gel spots, it has broad applicability.  相似文献   
128.
129.

Study design

A prospective treatment study with a new brace was conducted Objective. To evaluate radiological and subjective clinical results after one year conservative brace treatment with pressure onto lordosis at the thoracolumbar joint in children with scoliosis and kyphosis.

Summary of background data

Conservative brace treatment of adolescent scoliosis is not proven to be effective in terms of lasting correction. Conservative treatment in kyphotic deformities may lead to satisfactory correction. None of the brace or casting techniques is based on sagittal forces only applied at the thoracolumbar spine (TLI= thoracolumbar lordotic intervention). Previously we showed in patients with scoliosis after forced lordosis at the thoracolumbar spine a radiological instantaneous reduction in both coronal curves of double major scoliosis.

Methods

A consecutive series of 91 children with adolescent scoliosis and kyphosis were treated with a modified symmetric 30 degrees Boston brace to ensure only forced lordosis at the thoracolumbar spine. Scoliosis was defined with a Cobb angle of at least one of the curves [greater than or equal to] 25 degrees and kyphosis with or without a curve <25 degrees in the coronal plane. Standing radiographs were made i) at start, ii) in brace at beginning and iii) after one year treatment without brace.

Results

Before treatment start ??in brace?? radiographs showed a strong reduction of the Cobb angles in different curves in kyphosis and scoliosis groups (sagittal n = 5 all p < 0.001, pelvic obliquity p < 0.001). After one year of brace treatment in scoliosis and kyphosis group the measurements on radiographs made without brace revealed an improvement in 3 Cobb angles each.

Conclusion

Conservative treatment using thoracolumbar lordotic intervention in scoliotic and kyphotic deformities in adolescence demonstrates a marked improvement after one year also in clinical and postural criteria. An effect not obtained with current brace techniques.  相似文献   
130.
Interpreting the levels of genetic diversity in organisms with diverse life and population histories can be difficult. The processes and mechanisms regulating this diversity are complex and still poorly understood. However, endangered species typically have low genetic variation as a consequence of the effects of genetic drift in small populations. In this study we examine genetic variation in the critically endangered Chatham Island Taiko (Tchaik, Pterodroma magentae), one of the world’s rarest seabirds. The Taiko has a very small population size of between 120 and 150 individuals, including just 8–15 breeding pairs. We report surprisingly high mitochondrial and nuclear genetic diversity in this critically endangered long-lived species. We hypothesise that the present Taiko population has retained a significant proportion of its past genetic diversity. However, it is also possible that undiscovered birds are breeding in unknown areas, which could increase the population size estimate. Importantly, from a conservation perspective, we show that the high level of variation is unlikely to be maintained in the future since chicks currently being born have only a limited number of the mitochondrial DNA haplotypes found in adults. Reduced genetic variation will mean that our ability to infer past events and the population history of Taiko using genetics could soon be lost and the power to determine, for example, parentage and other close order relationships will be diminished. Therefore, the maintenance of genetic diversity in future generations is an important consideration for conservation management of the Taiko.  相似文献   
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