Regulation of hepatic branched-chain α-keto acid dehydrogenase kinase in a rat model for type 2 diabetes mellitus at different stages of the disease

Branched-chain α-keto acid dehydrogenase (BCKDH) kinase (BDK) is responsible for the regulation of BCKDH complex, which is the rate-limiting enzyme in the catabolism of branched-chain amino acids (BCAAs). In the present study, we investigated the expression and activity of hepatic BDK in spontaneous type 2 diabetes using hyperinsulinemic Zucker diabetic fatty rats aged 9 weeks and hyperglycemic, but not hyperinsulinemic rats aged 18 weeks. The abundance of hepatic BDK mRNA and total BDK protein did not correlate with changes in serum insulin concentrations. On the other hand, the amount of BDK bound to the complex and its kinase activity were correlated with alterations in serum insulin levels, suggesting that hyperinsulinemia upregulates hepatic BDK. The activity of BDK inversely corresponded with the BCKDH complex activity, which was suppressed in hyperinsulinemic rats. These results suggest that insulin regulates BCAA catabolism in type 2 diabetic rats by modulating the hepatic BDK activity.     

The use of repetitive DNA in cytogenetic studies of plant sex chromosomes

The structure of sex chromosomes in plants was analyzed by fluorescent in situ hybridization (FISH) with repetitive DNAs. FISH probes were successfully obtained from DNA libraries that were amplified from microdissected sex chromosomes. Some probes hybridized to the subtelomeric regions, where many kinds of repetitive DNAs are located with intrachromosomal similarity of their repeat units rather than interchromosomal similarity. For example, FISH with the subtelomeric repetitive sequence can easily show the location of the pseudoautosomal region (PAR) on the X chromosome of Silene latifolia. The other probes were localized on the interstitial region of the sex chromosomes. The interstitial region contains chloroplast DNAs or neighboring sequences of the internal telomeres, suggesting insertion or translocation occurred during differentiation of the sex chromosome. These data are very informative for understanding the structure of the plant sex chromosomes and their evolutionary process.     

Reduction of surgical site infection using a novel intervention (ROSSINI): study protocol for a randomised controlled trial

Background

Surgical site infection (SSI) is a common complication following abdominal surgery. It is associated with considerable morbidity and mortality, and its management results in significant cost to health services within both primary and secondary care. Some surgeons believe that the use of a wound-edge protection device may reduce the incidence of SSI. Whilst there is some encouraging evidence showing that such devices may lead to a reduction in SSI, there are no controlled trials of sufficient size or quality to support their routine use.

Methods/Design

750 patients will be recruited from around 20 surgical units within the United Kingdom. Patients undergoing laparotomy through any major abdominal incision for any indication, elective or emergency, are eligible. Patients under the age of 18, those undergoing a laparoscopic assisted procedure or who have undergone laparotomy within the previous 3 months, and those who are unable to give informed consent will be excluded. Patients will be randomised (1:1 ratio) to the use of a wound-edge protection device or no wound-edge protection device during surgery.Follow up will consist of blinded clinical wound reviews at 5-7 days and 30-33 days postoperatively with a self-completed questionnaire covering the intervening period. Quality of life questionnaires will be completed prior to surgery and at the subsequent wound review points and information on resource usage will also be captured.The primary outcome measure is SSI within 30 days of surgery. Secondary outcomes include the impact of the degree of wound contamination, patient comorbidity, and operative characteristics on the efficacy of a wound-edge protection device in reducing SSI and whether the use of a wound-edge protection device has an effect on health-related quality of life or length of hospital stay and is cost-effective.

Discussion

Rossini is the first multicentre observer-blinded randomised controlled trial of sufficient size and quality to establish whether the use of a wound-edge protection device in adult patients undergoing abdominal surgery leads to a lower rate of SSI. The results of this study will be used to inform current surgical practice and may potentially benefit patients undergoing surgery in the future.

Trial registration number

Current Controlled Trials ISRCTN: ISRCTN40402832

     

The Y chromosome-specific STS marker MS2 and its peripheral regions on the Y chromosome of the dioecious plant Silene latifolia.

Sex determination in Silene latifolia uses the XX/XY system. The recent evolution of dioecy in S. latifolia provides a unique opportunity to study the early stages of Y chromosome evolution. However, the current Y chromosome map still contains many large gaps with no available markers. In this study, a sequence tagged site (STS) marker, MS2, was isolated and mapped to the same locus as L8 on the Y chromosome. To investigate the peripheral regions of MS2, a bacterial artificial chromosome (BAC) library was constructed from a male plant, and the BAC clone containing MS2 (MS2-9d12F) was isolated from 32 640 clones with an average insert size of 115 kb. A 109-kb insert of the BAC clone was analyzed. BLASTX analysis showed 11 sequences similar to some known proteins, most of which are retrotransposon-like elements. The ORF Finder predicted 9 ORFs within MS2-9d12F. RT-PCR analyses revealed that only 4 of the 9 predicted ORFs are expressed in both male and female plants. These 4 ORFs are candidates for genes having counterparts on both the X and Y chromosomes. Dot-matrix plot analysis and a BLASTN search revealed LTR-like sequences close to the retrotransposon-like elements and high similarity to 3 known genomic sequences of S. latifolia. These results suggest an accumulation of retrotransposons and segmental duplications in peripheral regions of MS2 during the early stage of sex chromosome evolution.     

Homeostatic matching and nonlinear amplification at identified central synapses

Here we describe the properties of a synapse in the Drosophila antennal lobe and show how they can explain certain sensory computations in this brain region. The synapse between olfactory receptor neurons (ORNs) and projection neurons (PNs) is very strong, reflecting a large number of release sites and high release probability. This is likely one reason why weak ORN odor responses are amplified in PNs. Furthermore, the amplitude of unitary synaptic currents in a PN is matched to the size of its dendritic arbor. This matching may compensate for a lower input resistance of larger dendrites to produce uniform depolarization across PN types. Consistent with this idea, a genetic manipulation that lowers input resistance increases unitary synaptic currents. Finally, strong stimuli produce short-term depression at this synapse. This helps explain why PN odor responses are transient, and why strong ORN odor responses are not amplified as powerfully as weak responses.     

The relationship between pink salmon biomass and the body condition of short-tailed shearwaters in the Bering Sea: can fish compete with seabirds?

Seabirds and large fishes are important top predators in marine ecosystems, but few studies have explored the potential for competition between these groups. This study investigates the relationship between an observed biennial change of pink salmon (Oncorhynchus gorbuscha) biomass in the central Bering Sea (23 times greater in odd-numbered than in even-numbered years) and the body condition and diet of the short-tailed shearwater (Puffinus tenuirostris) that spends the post-breeding season there. Samples were collected with research gill nets over seven summers. Both species feed on krill, small fishes and squid. Although the mean pink salmon catch per unit effort (in mass) over the study region was not related significantly with shearwater's stomach content mass or prey composition, the pink salmon biomass showed a negative and significant relationship with the shearwater's body mass and liver mass (proxies of energy reserve). We interpret these results as evidence that fishes can negatively affect mean prey intake of seabirds if they feed on a shared prey in the pelagic ecosystem.