bluuebunny/crossref_metadata_2025 huggingface dataset:
The dipeptidyl peptidase‐4 inhibitor linagliptin lowers postprandial glucose and improves measures of β‐cell function in type 2 diabetes
Authors: Heise T. , Larbig M. , Patel S. , Seck T. , Hehnke U. , Woerle H.‐J. , Dugi K.
Published: May 2014

Progressive deterioration of pancreatic β‐cell function in patients with type 2 diabetes mellitus (T2DM) contributes to worsening of hyperglycaemia. To investigate the effects of the dipeptidyl peptidase‐4 inhibitor linagliptin on β‐cell function parameters, a pooled analysis of six randomized, 24‐week, placebo‐controlled, phase 3 trials of 5 mg of linagliptin daily was performed in 2701 patients with T2DM (linagliptin, n = 1905; placebo, n = 796). At week 24, observed improvements in HbA1c, fasting plasma glucose, and 2‐h postprandial glucose were significantly greater for linagliptin than placebo (all p < 0.0001). Homeostasis model assessment (HOMA)‐%β, as a surrogate marker of fasting β‐cell function, was significantly improved with linagliptin, and did not change with placebo (placebo‐adjusted mean ± s.e. change for linagliptin: 16.5 ± 4.6 (mU/l)/(mmol/l); p = 0.0003). Further study is required to determine if the significant improvement in HOMA‐%β with linagliptin will translate into long‐term improvements in β‐cell function.
Short‐ and long‐term racing performance ofStandardbred pacers and trotters after early surgical intervention for tarsal osteochondrosis
Authors: McCoy A. M. , Ralston S. L. , McCue M. E.
Published: May 2014

Reasons for performing study

Osteochondrosis (OC) is commonly diagnosed in youngStandardbred racehorses but its effect on performance when surgically treated at a young age is still incompletely understood. This is especially true forStandardbred pacers, which are underrepresented in the existing literature.

Objective

To characterise the short‐ (2‐year‐old) and long‐term (through 5‐year‐old) racing performance inStandardbred pacers and trotters after early surgical intervention (<17 months of age) for tarsalOC.

Study design

Retrospective clinical study.

Methods

The study population consisted of related, age‐matchedStandardbred racehorses (n = 278; 151 pacers, 127 trotters) with (n = 133) or without (n = 145) one or more tarsalOClesions. AllOC‐affected horses were treated surgically prior to being sold as yearlings. Data obtained from publicly available race records for each horse included starts, wins, finishes in the top 3 (win, place or show), earnings and fastest time. Comparisons betweenOC‐affected and unaffected horses were made for the entire population and within gaits. A smaller related population (n = 94) had these performance measures evaluated for their 2–5‐year‐old racing seasons.

Results

Osteochondrosis status was associated with few performance measures. Trotters were at higher risk for lesions of the medial malleolus but lower risk for lesions of the distal intermediate ridge of the tibia than were pacers. Horses with bilateralOClesions and lateral trochlear ridge (LTR) lesions started fewer races at 2 years of age than those with unilateral lesions or withoutLTRlesions.

Conclusions

Osteochondrosis seemed to have minimal effect on racing performance in this cohort, although horses with bilateral andLTRlesions started fewer races at 2 years. There was evidence for different distribution ofOClesions among pacers and trotters, which should be explored further.Standardbreds undergoing early removal of tarsalOClesions can be expected to perform equivalently to their unaffected counterparts.
Freeze Shoe Sampler for the Collection of Hyporheic Zone Sediments and Porewater
Authors: Bianchin M. , Smith L. , Beckie R.
Published: May 2014

The Starr and Ingleton (1992) drive point piston sampler (DPPS) design was modified by fitting it with a Murphy and Herkelrath (1996) type sample‐freezing drive shoe (SFDS), which uses liquid carbon dioxide as a cryogen. Liquid carbon dioxide was used to freeze sediments in the lower 0.1 m of the core and the drive‐point piston sealed the core at the top preserving the reductive‐oxidation (redox) sensitive sediments from the atmosphere and maintaining natural stratigraphy. The use of nitrogen gas to provide positive pressure on the gas system blocked the ingress of water which froze on contact with the cryogen thus blocking the gas lines with ice. With this adaptation to the gas system cores could be collected at greater depths beneath the static water level. This tool was used to collect intact saturated sediment cores from the hyporheic zone of the tidally influenced Fraser River in Vancouver, British Columbia, Canada where steep geochemical and microbial gradients develop within the interface between discharging anaerobic groundwater and recharging aerobic river water. In total, 25 cores driven through a 1.5 m sampling interval were collected from the river bed with a mean core recovery of 75%. The ability to deploy this method from a fishing vessel makes the tool more cost effective than traditional marine‐based drilling operations which often use barges, tug boats, and drilling rigs.
Geothermal Waste Heat Utilization from In Situ Thermal Bitumen Recovery Operations
Authors: Nakevska Nevenka , Schincariol Robert A. , Dehkordi S. Emad , Cheadle Burns A.
Published: May 2014

In situ thermal methods for bitumen extraction introduce a tremendous amount of energy into the reservoirs raising ambient temperatures of 13 °C to as high as 200 °C at the steam chamber edge and 50 °C along the reservoir edge. In essence these operations have unintentionally acted as underground thermal energy storage systems which can be recovered after completion of bitumen extraction activities. Groundwater flow and heat transport models of the Cold Lake, Alberta, reservoir, coupled with a borehole heat exchanger (BHE) model, allowed for investigating the use of closed‐loop geothermal systems for energy recovery. Three types of BHEs (single U‐tube, double U‐tube, coaxial) were tested and analyzed by comparing outlet temperatures and corresponding heat extraction rates. Initial one year continuous operation simulations show that the double U‐tube configuration had the best performance producing an average temperature difference of 5.7 °C, and an average heat extraction of 41 W/m. Given the top of the reservoir is at a depth of 400 m, polyethylene piping provided for larger extraction gains over more thermally conductive steel piping. Thirty year operation simulations illustrate that allowing 6 month cyclic recovery periods only increases the loop temperature gain by a factor of 1.2 over continuous operation. Due to the wide spacing of existing boreholes and reservoir depth, only a small fraction of the energy is efficiently recovered. Drilling additional boreholes between existing wells would increase energy extraction. In areas with shallower bitumen deposits such as the Athabasca region, i.e. 65 to 115 m deep, BHE efficiencies should be larger.
The effects of health education on knowledge about Alzheimer's disease and health‐promoting behaviours of older Chinese adults in a nursing home: A pilot study
Authors: Du Li , Hu Jie
Published: May 2014

This pilot study tested the effects of health education on knowledge of Alzheimer's disease (AD) and health‐promotion lifestyles among older Chinese adults residing in a nursing home in Wuhan. A convenience sample of 35 elders without AD was recruited from a nursing home in Wuhan and provided with a 5 week health education intervention. Participants had little knowledge about AD and had an intermediate level of health promotion. After receiving the intervention, there were significant increases in scores on AD knowledge (F = 29.69, df = 1.23, P < 0.01) and health‐promotion lifestyle (F = 4.39, df = 2, P < 0.05). These results suggest that the intervention on AD knowledge and health promotion was effective for elders in this study. Nurses should therefore provide education for elders in nursing homes to improve their AD knowledge and health‐promotion lifestyles, and to prevent or ameliorate AD.
PermVeg: A Model to Design Crop Sequences for Permanent Vegetable Production Systems in the Red River Delta, Vietnam
Authors: Huong P. T. T. , Everaarts A. P. , van den Berg W. , Neeteson J. J. , Struik P. C.
Published: May 2014

The constraints in current vegetable production systems in the Red River Delta, Vietnam, in which vegetables are rotated with flooded rice, called for the design of alternative systems of permanent vegetable production. The practical model, PermVeg, was developed to generate vegetable crop sequences for permanent vegetable production, as based on a set of rules and restrictions. Permanent vegetable production systems were designed based on the following five scenarios: (i) increased profit, (ii) reduced labour requirement, (iii) decreased costs of pesticide use, (iv) improved crop biodiversity and (v) selected crops with low‐perishable products. PermVeg showed that theoretically all selected crop sequences in the different alternative systems increased farmers' income compared to the traditional system. The system with the highest profitability increased profit per hectare per day by a factor of three as compared to the traditional system. Labour requirement in days per hectare per day in a crop sequence also increased in all systems. Except for the system with low costs of pesticide use, permanent vegetable production systems had higher pesticide costs than the traditional, vegetable – flooded rice crop sequence. Given the model outcomes, permanent vegetable production systems can be an option to improve farmers' income, to provide labour opportunities, and, in the case of the high crop biodiversity system, to contribute to the development of sustainable production systems. The PermVeg model can act as a practical tool to rapidly explore crop sequence options and to help farmers' decision‐making.
Economic indicators predict changes in college student optimism for life events
Authors: Lench Heather C. , Bench Shane W.
Published: May 2014

This investigation explored the extent to which an economic recession predicted changes in college students' optimism about the length and quality of their futures. In a cross‐sectional design, college students in the United States rated their likelihood of divorcing, being unhappy in their career, and living past age 60, at time points before, during, and in the aftermath of an economic recession (2007–2010). Economic indicators, particularly gas prices, predicted decreased optimism as the indicators worsened. After the recession, however, optimism rebounded. The findings reveal that people's expectations for their personal futures are generally sensitive to the state of the national economy.
The challenge of promoting algorithmic thinking of both sciences‐ and humanities‐oriented learners
Authors: Katai Z.
Published: May 2014

The research results we present in this paper reveal that properly calibrated e‐learning tools have potential to effectively promote the algorithmic thinking of both science‐oriented and humanities‐oriented students. After students had watched an illustration (by a folk dance choreography) and an animation of the studied sorting algorithm (bubble sort), they were invited to predict and perform [(1) to reconstruct on the same input; (2) to orchestrate on a random sequence stored in a white array; (3) to orchestrate on a black‐box sequence] the entire step sequence of the algorithm (using the interactive visual learning environment we developed). The results of the experiment show that while science‐oriented students' performance proved superior to those of their humanities‐oriented colleagues, the differences were observed to diminish as both groups advanced with their e‐learning tasks. Although drawing general conclusions would be premature, we can conclude that there are no unbridgeable differences in the way these two groups relate to e‐learning processes that aim to promote algorithmic thinking. Our findings also emphasize the key importance of some motivational principles in facilitating algorithmic thinking: the principle of moderate and progressive challenge, the principle of gradual shift from concrete to abstract and the principle of genuine active involvement.
Interactive effects of competition and social environment on the expression of sexual dimorphism
Authors: De Lisle S. P. , Rowe L.
Published: May 2014

The expression of sexual dimorphism is expected to be influenced by the acquisition of resources available to allocate to trait growth, combined with sex‐specific patterns of resource allocation. Resource acquisition in the wild may be mediated by a variety of ecological factors, such as the density of interspecific competitors. Allocation may in turn depend on social contexts, such as sex ratio, that alter the pay‐off for investment in sexual traits. How these factors interact to promote or constrain the expression and evolution of sexual dimorphism is poorly understood. We manipulated sex ratio and interspecific resource competition over the growing season of red‐spotted newts (Notophthalmus viridescens) in artificial ponds. Fish competitors had a stronger effect on female than male growth, which effectively eliminated the expression of sexual size dimorphism. In addition, newt sex ratio influenced fish growth, leading to reduction in fish mass with an increase in female newt frequency. Fish also reduced the expression of male tail height, a sexually selected trait, but only in tanks with a female‐biased sex ratio. This suggests males alter their resource allocation pattern in response to the strength of sexual selection. Our results demonstrate that ecologically and socially mediated interactions between sex‐specific resource acquisition and allocation can contribute to variation in the expression of sexual dimorphism.
Inbreeding depression in male gametic performance
Authors: Losdat S. , Chang S.‐M. , Reid J. M.
Published: May 2014

One key objective in evolutionary ecology is to understand the magnitude of inbreeding depression expressed across sex‐specific components of fitness. One major component of male fitness is fertilization success, which depends on male gametic performance (sperm and pollen performance in animals and plants, respectively). Inbreeding depression in male gametic performance could create sex‐specific inbreeding depression in fitness, increase the benefit of inbreeding avoidance and reduce the efficacy of artificial insemination and pollination. However, there has been no assessment of the degree to which inbreeding generally depresses male gametic performance and hence post‐copulatory or post‐pollination fertilization success. Because inbreeding depression is understood to be a property of diploid entities, it is not clear what degree of inbreeding depression in haploid gametic performance should be expected. Here, we first summarize how inbreeding depression in male gametic performance could potentially arise through gene expression in associated diploid cells and/or reduced genetic diversity among haploid gametes. We then review published studies that estimate the magnitude of inbreeding depression in traits measuring components of sperm or pollen quantity, quality and competitiveness. Across 51 published studies covering 183 study traits, the grand mean inbreeding load was approximately one haploid lethal equivalent, suggesting that inbreeding depresses male gametic performance across diverse systems and traits. However, there was an almost complete lack of explicit estimates from wild populations. Future studies should quantify inbreeding depression in systematic sets of gametic traits under naturally competitive and noncompetitive conditions and quantify the degree to which gamete phenotypes and performance reflect haploid vs. diploid gene expression.
Sex drives intracellular conflict in yeast
Authors: Harrison E. , MacLean R. C. , Koufopanou V. , Burt A.
Published: May 2014

Theory predicts that sex can drive the evolution of conflict within the cell. During asexual reproduction, genetic material within the cell is inherited as a single unit, selecting for cooperation both within the genome as well as between the extra‐genomic elements within the cell (e.g. plasmids and endosymbionts). Under sexual reproduction, this unity is broken down as parental genomes are distributed between meiotic progeny. Genetic elements able to transmit to more than 50% of meiotic progeny have a transmission advantage over the rest of the genome and are able to spread, even where they reduce the fitness of the individual as a whole. Sexual reproduction is therefore expected to drive the evolution of selfish genetic elements (SGEs). Here, we directly test this hypothesis by studying the evolution of two independent SGEs, the 2‐μm plasmid and selfish mitochondria, in populations of Saccharomyces cerevisiae. Following 22 rounds of sexual reproduction, 2‐μm copy number increased by approximately 13.2 (± 5.6) copies per cell, whereas in asexual populations copy number decreased by approximately 5.1 (± 1.5) copies per cell. Given that the burden imposed by this parasite increases with copy number, these results support the idea that sex drives the evolution of increased SGE virulence. Moreover, we found that mitochondria that are respiratory‐deficient rapidly invaded sexual but not asexual populations, demonstrating that frequent outcrossed sex can drive the de novo evolution of genetic parasites. Our study highlights the genomic perils of sex and suggests that SGEs may play a key role in driving major evolutionary transitions, such as uniparental inheritance.
Maternal effects are long‐lasting and influence female offspring's reproductive strategy in the swordtail fish Xiphophorus multilineatus
Authors: Murphy A. D. , Goedert D. , Morris M. R.
Published: May 2014

The adaptive benefits of maternal investment into individual offspring (inherited environmental effects) will be shaped by selection on mothers as well as their offspring, often across variable environments. We examined how a mother's nutritional environment interacted with her offspring's nutritional and social environment in Xiphophorus multilineatus, a live‐bearing fish. Fry from mothers reared on two different nutritional diets (HQ = high quality and LQ = low quality) were all reared on a LQ diet in addition to being split between two social treatments: exposed to a large adult male during development and not exposed. Mothers raised on a HQ diet produce offspring that were not only initially larger (at 14 days of age), but grew faster, and were larger at sexual maturity. Male offspring from mothers raised on both diets responded to the exposure to courter males by growing faster; however, the response of their sisters varied with mother's diet; females from HQ diet mothers reduced growth if exposed to a courter male, whereas females from LQ diet mothers increased growth. Therefore, we detected variation in maternal investment depending on female size and diet, and the effects of this variation on offspring were long‐lasting and sex specific. Our results support the maternal stress hypothesis, with selection on mothers to reduce investment in low‐quality environments. In addition, the interaction we detected between the mother's nutritional environment and the female offspring's social environment suggests that female offspring adopted different reproductive strategies depending on maternal investment.
Immersion challenge with low and highly virulent infectious salmon anaemia virus reveals different pathogenesis in Atlantic salmon, Salmo salar L.
Authors: McBeath A , Aamelfot M , Christiansen D H , Matejusova I , Markussen T , Kaldhusdal M , Dale O B , Weli S C , Falk K
Published: May 2014

The salmonid orthomyxovirus infectious salmon anaemia virus (ISAV) causes disease of varying severity in farmed Atlantic salmon, Salmo salar L. Field observations suggest that host factors, the environment and differences between ISAV strains attribute to the large variation in disease progression. Variation in host mortality and dissemination of ISAV isolates with high and low virulence (based on a previously published injection challenge) were investigated using immersion challenge. Virus dissemination was determined using real‐time PCR and immunohistochemistry in several organs, including blood. Surprisingly, the low virulent virus (LVI) replicated and produced nucleoprotein at earlier time points post‐infection compared to the virus of high virulence (HVI). This was particularly noticeable in the gills as indicated by different viral load profiles. However, the HVI reached a higher maximum viral load in all tested organs and full blood. This was associated with a higher mortality of 100% as compared to 20% in the LVI group by day 23 post‐infection. Immersion challenge represented a more natural infection method and suggested that specific entry routes into the fish may be of key importance between ISAV strains. The results suggest that a difference in virulence is important for variations in virus dissemination and pathogenesis (disease development).
Single and Sequential Application of Electrolyzed Water with Benzalkonium Chloride or Peracetic Acid for Removal of Staphylococcus Aureus Biofilms
Authors: Vázquez‐Sánchez D. , Cabo M.L. , Rodríguez‐Herrera J.J.
Published: May 2014

The effectiveness of electrolyzed water (EW) to remove biofilms formed on stainless steel by Staphylococcus aureus strains isolated from fishery products was assessed. The bactericidal activity of EW against biofilms was hardly any affected by any variations in the pH of production. Neutral EW (NEW) was therefore used in subsequent studies as it has a higher potential for long‐term application than acidic EW (due to a lower corrosiveness and toxicity) and due to the higher yield rate of the production unit at neutral pH.

The application of NEW caused a high reduction in the number of viable biofilm cells initially. However, a high available chlorine concentration (800 mg/L) was needed to achieve logarithmic reductions (LR) demanded by the European quantitative surface test of bactericidal activity (≥ 4 log CFU/cm2 after 5 min). A double sequential application of NEW at much lower concentrations for 5 min each allowed LR ≥ 4 log CFU/cm2 to be reached in most of the experimental range. Sequential applications of NEW and either benzalkonium chloride or peracetic acid (PAA) showed a similar effect, with PAA‐NEW being most effective. The combination of NEW with other antimicrobial treatments can thus be an environmentally friendly alternative to disinfection protocols traditionally used in the food industry.

Practical Applications

Spain is the largest producer and the second largest consumer of seafood in the European Union, thus ensuring the safety of these products is of outmost importance. However, a high incidence of Staphylococcus aureus was recently found in fishery products marketed in Spain, which questioned the efficacy of disinfectants traditionally applied in the food industry. This study focused on electrolyzed water (EW) because it is an environmentally friendly, safe‐to‐use and relatively inexpensive option. The data obtained in this study demonstrated that the combination of neutral EW and other disinfectants resulted in an effective alternative to control the contamination of food‐processing facilities by foodborne pathogens such as S. aureus.
Testosterone or Oestradiol Implants in the Medial Preoptic Area Induce Mating in Noncopulating Male Rats
Authors: Antonio‐Cabrera E. , Paredes R. G.
Published: May 2014

Noncopulating (NC) male rats are those males that do not mount, intromit or ejaculate when repeatedly tested with receptive females. The lack of sexual behaviour in these males is not associated with alterations in testosterone or oestradiol (E2) plasma concentrations. Instead, it has been shown that androgen receptors are higher and oestrogen receptors are lower in the medial preoptic area (MPOA) of NC male rats than those observed in copulating (C) male rats. We have also observed reduced aromatase activity in the MPOA (but not in other brain regions) of NC male rats. The aim of the present study was to determine whether testosterone or E2 implants in the MPOA of NC male rats could induce sexual behaviour. Accordingly, in Experiment 1, we evaluated the long‐term effects of testosterone or E2 implants in the MPOA, the ventromedial nucleus of the hypothalamus or the medial amygdala with respect to inducing sexual behaviour in castrated C male rats. Male rats were bilaterally implanted with a guide cannula, either empty or containing testosterone or E2. Starting 1 week later, all male rats were mated once weekly for 5 months. As described previously, the site where hormone implants most consistently induced sexual behaviour in castrated C male rats was the MPOA. Experiment 1 extended these findings showing that the males continued mating even 5 months after the implant. In the second experiment, NC males were implanted in the MPOA with a guide cannula empty or filled with testosterone or E2. One week after the testosterone or E2 implant, the percentage of males that mounted and intromitted started to increase and, 5 weeks after the implant, 50% of the subjects displayed mounts and intromissions. All NC males implanted with testosterone ejaculated consistently from week 11 after the implant until the end of testing (5 months), whereas all subjects implanted with E2 ejaculated from week 16 after the implant until the end of testing. These results support the hypothesis that, in the MPOA of NC male rats, there is a hormonal alteration associated with the lack of sexual behaviour.
Diurnal and Circadian Oscillations in Expression of Kisspeptin, Kisspeptin Receptor and Gonadotrophin‐Releasing Hormone 2 Genes in the Grass Puffer, A Semilunar‐Synchronised Spawner
Authors: Ando H. , Ogawa S. , Shahjahan Md. , Ikegami T. , Doi H. , Hattori A. , Parhar I.
Published: May 2014

In seasonally breeding animals, the circadian and photoperiodic regulation of neuroendocrine system is important for precisely‐timed reproduction. Kisspeptin, encoded by the Kiss1 gene, acts as a principal positive regulator of the reproductive axis by stimulating gonadotrophin‐releasing hormone (GnRH) neurone activity in vertebrates. However, the precise mechanisms underlying the cyclic regulation of the kisspeptin neuroendocrine system remain largely unknown. The grass puffer, Takifugu niphobles, exhibits a unique spawning rhythm: spawning occurs 1.5–2 h before high tide on the day of spring tide every 2 weeks, and the spawning rhythm is connected to circadian and lunar‐/tide‐related clock mechanisms. The grass puffer has only one kisspeptin gene (kiss2), which is expressed in a single neural population in the preoptic area (POA), and has one kisspeptin receptor gene (kiss2r), which is expressed in the POA and the nucleus dorsomedialis thalami. Both kiss2 and kiss2r show diurnal variations in expression levels, with a peak at Zeitgeber time (ZT) 6 (middle of day time) under the light/dark conditions. They also show circadian expression with a peak at circadian time 15 (beginning of subjective night‐time) under constant darkness. The synchronous and diurnal oscillations of kiss2 and kiss2r expression suggest that the action of Kiss2 in the diencephalon is highly dependent on time. Moreover, midbrain GnRH2 gene (gnrh2) but not GnRH1 or GnRH3 genes show a unique semidiurnal oscillation with two peaks at ZT6 and ZT18 within a day. The cyclic expression of kiss2, kiss2r and gnrh2 may be important in the control of the precisely‐timed diurnal and semilunar spawning rhythm of the grass puffer, possibly through the circadian clock and melatonin, which may transmit the photoperiodic information of daylight and moonlight to the reproductive neuroendocrine centre in the hypothalamus.
Evidence that Insulin Signalling in Gonadotrophin‐Releasing Hormone and Kisspeptin Neurones does not Play an Essential Role in Metabolic Regulation of Fertility in Mice
Authors: Evans M. C. , Rizwan M. , Mayer C. , Boehm U. , Anderson G. M.
Published: May 2014

Insulin in the brain plays an important role in regulating reproductive function, as demonstrated via conditional brain‐specific insulin receptor (Insr) deletion (knockout). However, the specific neuronal target cells mediating the central effects of insulin on the reproductive axis remain unidentified. We first investigated whether insulin can act via direct effects on gonadotrophin‐releasing hormone (GnRH) neurones. After clearly detecting Insr mRNA in an immunopurified GnRH cell fraction, we confirmed the presence of insulin receptor protein (InsR) in approximately 82% of GnRH neurones using dual‐label immunohistochemistry. However, we did not observe any insulin‐induced phospho‐Akt (pAkt) or phospho‐extracellular‐signal‐regulated kinase 1/2 in GnRH neurones, and therefore we investigated whether insulin signals via kisspeptin neurones to modulate GnRH release. Using dual‐label immunohistochemistry, InsRs were detected only in approximately 5% of kisspeptin‐immunoreactive cells. Insulin‐induced pAkt was not observed in any kisspeptin‐immunoreactive cells in either the rostral periventricular region of the third ventricle or arcuate nucleus in response to 200 mU of insulin treatment, although a more pharmacological dose (10 U) induced pronounced (> 20%) pAkt–kisspeptin coexpression in both regions. To confirm that insulin signalling via kisspeptin neurones does not critically modulate reproductive function, we generated kisspeptin‐specific InsR knockout (KIRKO) mice and assessed multiple reproductive and metabolic parameters. No significant differences in puberty onset, oestrous cyclicity or reproductive competency were observed in the female or male KIRKO mice compared to their control littermates. However, significantly decreased fasting insulin (P < 0.05) and a nonsignificant trend towards reduced body weight were observed in male KIRKO mice. Thus, InsR signalling in kisspeptin cells is not critical for puberty onset or reproductive competency, although it may have a small metabolic effect in males.
AMP‐activated protein kinase: a key regulator of energy balance with many roles in human disease
Authors: Grahame Hardie D.
Published: May 2014

The AMP‐activated protein kinase (AMPK) is a sensor of cellular energy status that regulates cellular and whole‐body energy balance. A recently reported crystal structure has illuminated the complex regulatory mechanisms by which AMP and ADP cause activation of AMPK, involving phosphorylation by the upstream kinase LKB1. Once activated by falling cellular energy status, AMPK activates catabolic pathways that generate ATP whilst inhibiting anabolic pathways and other cellular processes that consume ATP. A role of AMPK is implicated in many human diseases. Mutations in the γ2 subunit cause heart disease due to excessive glycogen storage in cardiac myocytes, leading to ventricular pre‐excitation. AMPK‐activating drugs reverse many of the metabolic defects associated with insulin resistance, and recent findings suggest that the insulin‐sensitizing effects of the widely used antidiabetic drug metformin are mediated by AMPK. The upstream kinase LKB1 is a tumour suppressor, and AMPK may exert many of its antitumour effects. AMPK activation promotes the oxidative metabolism typical of quiescent cells, rather than the aerobic glycolysis observed in tumour cells and cells involved in inflammation, explaining in part why AMPK activators have both antitumour and anti‐inflammatory effects. Salicylate (the major in vivo metabolite of aspirin) activates AMPK, and this could be responsible for at least some of the anticancer and anti‐inflammatory effects of aspirin. In addition to metformin and salicylates, novel drugs that modulate AMPK are likely to enter clinical trials soon. Finally, AMPK may be involved in viral infection: downregulation of AMPK during hepatitis C virus infection appears to be essential for efficient viral replication.
A daily diary study on ambidextrous leadership and self‐reported employee innovation
Authors: Zacher Hannes , Wilden Ruth G.
Published: May 2014

Ambidextrous leadership involves a combination of behaviours that stimulate employee exploration (‘opening behaviour’) and behaviours that facilitate exploitation of ideas (‘closing behaviour’). We hypothesized that the interaction between leaders’ daily opening and closing behaviours (i.e., ambidextrous leadership) predicts employees’ daily self‐reported innovative performance. Results based on diary data provided by 113 employees across five work days supported this hypothesis: daily self‐reported innovative performance was highest when both daily opening and closing behaviours were high.

Practitioner points

Findings suggest that selecting and training leaders to engage in ‘opening behaviour’, which stimulates employee exploration, result in higher daily employee innovation.

Leaders should additionally be selected and trained to engage in ‘closing behaviour’, which facilitates exploitation of new ideas, in order to further boost the positive effect of ‘opening behaviour’ on daily employee innovation.
Selected terpenoids from medicinal plants modulate endoplasmic reticulum stress in metabolic disorders
Authors: Beukes Natasha , Levendal Ruby-Ann , Frost Carminita L
Published: May 2014

Objectives

The majority of research performed on cellular stress and apoptosis focuses on mitochondrial dysfunction; however, the importance of the endoplasmic reticulum dysfunction and the link to metabolic diseases has gained a substantial interest. This review focuses on the potential of terpenoids to influence endoplasmic reticulum stress and the possible role terpenoids play as the treatment of metabolic diseases.

Key findings

Metabolic diseases develop as a result of a cascade of cellular pathways. In most cases, cells are able to compensate for the disruption of the cellular homeostasis although the initiation of response pathways; however, chronic stress initiates apoptotic pathways. This reviewed (1) showed the importance of phytoterpenoids to influence endoplasmic reticulum (ER) stress and homeostasis, (2) showed how regulating ER stress affect the cell survival and death, and (3) highlighted some examples of how the progression of metabolic diseases can be influenced by ER.

Due to the substantial number of terpenoids that have been identified in literature, this review gave examples of 21 terpenoids that have been documented to have an effect on the different proteins associated with ER stress, how these plant terpenoids influence ER dysfunction and metabolic diseases such as diabetes, cancer, liver, and neurological diseases and parasitic infections.
Melatonin synthesis impairment as a new deleterious outcome of diabetes‐derived hyperglycemia
Authors: Amaral Fernanda G. , Turati Ariane O. , Barone Mark , Scialfa Julieta H. , do Carmo Buonfiglio Daniella , Peres Rafael , Peliciari‐Garcia Rodrigo A. , Afeche Solange C. , Lima Larissa , Scavone Cristoforo , Bordin Silvana , Reiter Russel J. , Menna‐Barreto Luiz , Cipolla‐Neto José
Published: May 2014

Melatonin is a neurohormone that works as a nighttime signal for circadian integrity and health maintenance. It is crucial for energy metabolism regulation, and the diabetes effects on its synthesis are unresolved. Using diverse techniques that included pineal microdialysis and ultrahigh‐performance liquid chromatography, the present data show a clear acute and sustained melatonin synthesis reduction in diabetic rats as a result of pineal metabolism impairment that is unrelated to cell death. Hyperglycemia is the main cause of several diabetic complications, and its consequences in terms of melatonin production were assessed. Here, we show that local high glucose (HG) concentration is acutely detrimental to pineal melatonin synthesis in rats both in vivo and in vitro. The clinically depressive action of high blood glucose concentration in melatonin levels was also observed in type 1 diabetes patients who presented a negative correlation between hyperglycemia and 6‐sulfatoxymelatonin excretion. Additionally, high‐mean‐glycemia type 1 diabetes patients presented lower 6‐sulfatoxymelatonin levels when compared to control subjects. Although further studies are needed to fully clarify the mechanisms, the present results provide evidence that high circulating glucose levels interfere with pineal melatonin production. Given the essential role played by melatonin as a powerful antioxidant and in the control of energy homeostasis, sleep and biological rhythms and knowing that optimal glycemic control is usually an issue for patients with diabetes, melatonin supplementation may be considered as an additional tool to the current treatment.
A guide to critiquing a research paper on clinical supervision: enhancing skills for practice
Authors: Fothergill A. , Lipp A.
Published: May 2014

Accessible summary

This paper aims to do two things: First, we want to show the reader how to critique a published research paper. The second aim is to take the reader through the various stages of critiquing using a guide.

In the paper, we explain at each stage the research terms that can deter the novice critic from reading and understanding the findings in research.

From this we hope the reader will have developed an ability to do their own critiquing, so that they are better informed about the quality of research that influences nursing practice.

In this paper we have taken a previously published paper on the effectiveness of clinical supervision and undertaken a systematic critique of the merits of this quantitative research using a recognized critiquing framework compiled by Coughlan et al. (2007). Our purpose was twofold: First, we wanted to demonstrate the various stages of critiquing a paper in order that the reader might make an informed judgment of the quality and relevance of the research. The reader/critic is then able to decide whether to use this research in their own practice. Second, we wanted to assist the reader to develop their own critical, analytical skills through methodically appraising the merits of published research. Nursing as an evidence‐based profession requires nurses at both pre‐ and post‐registration level to be able to understand, synthesize and critique research, this being a fundamental part of many nursing curricula. These have become core skills to acquire because implementing up‐to‐date evidence is the cornerstone of contemporary nursing practice. We have provided in this paper a template for critiquing, which is based on our combined experiences as academics specifically in teaching at the bachelor, master's and doctoral levels.
Effect of feeding different levels of wheat roti on nutrient utilization and blood metabolite profile in semi‐captive Asian elephants (Elephas maximus)
Authors: Das A. , Saini M. , Katole S. , Kullu S. S. , Swarup D. , Sharma A. K.
Published: May 2014

This experiment was conducted to study the effect of different levels of wheat roti (WR) on nutrient utilization and blood metabolites in Asian elephants fed roughages ad libitum. Nine (3 M, 6 F) Asian elephants (14–52 years of age, 1909–3968 kg BW) were used in an experiment based on replicated Latin square design. Animals in each group (n = 3) were assigned to one of the three dietary treatments in a manner that animals in all the three groups were exposed to all the three treatments in three different periods. Each feeding trial comprised 30 days (25 days of adaptation and 5 days collection period). The amount of WR fed to the elephants was 0.18, 0.12 and 0.06% of BW in groups I, II and III, respectively. They were allowed to forage in the nearby forests for 6 h/day and to bathe for 2 h/day. The animals had ad libitum access to cut Rohini (Mallotus philippensis) trees in their night shelter. Intake and apparent digestibility of dry matter (DM), crude protein (CP), gross energy (GE), Ca, P, Fe, Cu and Zn were measured. Feed consumption was not significantly different among the groups. Significant (p < 0.01) decrease in digestibility of DM and GE and blood glucose concentration was observed with decreased level of WR in the diet. Feeding of WR at 0.06% of BW supplied adequate amount of DE, CP, Ca, P, Fe, Cu and Zn to meet requirement for adult maintenance. Feeding of WR in excess of 0.06% of BW supplied DE in excess of requirement, increased blood glucose concentration which may cause obesity and other associated health problems. It was concluded that the amount of WR should be restricted to 0.06% of BW in the diet of captive Asian elephants.
Effect of root planing on surface topography: an in‐vivo randomized experimental trial
Authors: Rosales‐Leal J. I. , Flores A. B. , Contreras T. , Bravo M. , Cabrerizo‐Vílchez M. A. , Mesa F.
Published: May 2014

Background and Objective

The root surface topography exerts a major influence on clinical attachment and bacterial recolonization after root planing. In‐vitro topographic studies have yielded variable results, and clinical studies are necessary to compare root surface topography after planing with current ultrasonic devices and with traditional manual instrumentation. The aim of this study was to compare the topography of untreated single‐rooted teeth planed in vivo with a curette, a piezoelectric ultrasonic (PU) scraper or a vertically oscillating ultrasonic (VOU) scraper.

Material and Methods

In a randomized experimental trial of 19 patients, 44 single‐rooted teeth were randomly assigned to one of four groups for: no treatment; manual root planing with a curette; root planing with a PU scraper; or root planing with a VOU scraper. Post‐treatment, the teeth were extracted and their topography was analyzed in 124 observations with white‐light confocal microscopy, measuring the roughness parameters arithmetic average height, root‐mean‐square roughness, maximum height of peaks, maximum depth of valleys, absolute height, skewness and kurtosis.

Results

The roughness values arithmetic average height and root‐mean‐square roughness were similar after each treatment and lower than after no treatment ( p < 0.05). Absolute height was lower in the VOU group than in the untreated ( p = 0.0026) and PU (p = 0.045) groups. Surface morphology was similar after the three treatments and was less irregular than in the untreated group. Values for the remaining roughness parameters were similar among all treatment groups ( p > 0.05).

Conclusion

Both ultrasonic devices reduce the roughness, producing a similar topography to that observed after manual instrumentation with a curette, to which they appear to represent a valid alternative.
Fish as parasites: an insight into evolutionary convergence in adaptations for parasitism
Authors: Leung T. L. F.
Published: May 2014

Fish are the most diverse group of living vertebrates on the planet with 32 000 living species. They have diversified to fill a wide variety of ecological niches. Some species have formed close ecological interactions with other aquatic species that can be best described as symbiotic or even parasitic. Some fish species have evolved different ways to exploit invertebrates, ranging from using their body as a site for depositing their eggs and larvae to actually sheltering inside the invertebrate themselves and feeding on the organs of their host. Other fish species are frequently associated with larger aquatic vertebrates, attaching to them for either phoretic or feeding purposes or both. The aim of this review is to provide an overview of some general patterns in these symbiotic or parasitic relationships, comparing them with more ‘traditional’ parasites and symbionts, and discuss the insight they can offer on both the evolutionary process that leads to parasitism, as well as the evolutionary pathways of fishes as a whole.
Effects of alendronate on the peri‐implant bone in rats
Authors: Oh KC , Moon HS , Lee JH , Park YB , Kim J‐H
Published: May 2014

Objectives

The purpose of this study was to determine the effects of alendronate on the peri‐implant bone in rat maxillae with the aid of micro‐computed tomographic, histologic, and biochemical analyses.

Materials and Methods

Thirty‐six male Sprague‐Dawley rats were used. After extraction of the maxillary first molars, each rat was given periodic subcutaneous injections of either alendronate (alendronate group) or saline (control group). Customized implants were placed bilaterally 4 weeks after these injections. The rats were sacrificed at either 4, 8, or 12 weeks after implantation (4‐, 8‐, and 12‐week groups, respectively; n = 6 rats per group). Microcomputed tomographic and histologic analyses were conducted for all rats. Biochemical analyses were performed at four time points for the 12‐week groups.

Results

There were no significant differences between the groups on microcomputed tomographic and histologic analyses. All of the measured biochemical parameters tended to decrease over time, with significant differences among some time points within each group. The serum osteocalcin level was significantly lower in the 12‐week alendronate group than in the control group (P < 0.05).

Conclusions

Three approaches were utilized in evaluating the effects of alendronate. It appears serum osteocalcin levels may serve as an adjuvant marker for this purpose, although further studies are required to confirm this.
Differential responses of size‐based functional groups to bottom–up and top–down perturbations in pelagic food webs: a meta‐analysis
Authors: Hulot Florence D. , Lacroix Gérard , Loreau Michel
Published: May 2014

We performed a meta‐analysis of 31 lake mesocosm experiments to investigate differences in the responses of pelagic food chains and food webs to nutrient enrichment and fish presence. Trophic levels were divided into size‐based functional groups (phytoplankton into highly edible and poorly edible algae, and zooplankton into small herbivores, large herbivores and omnivorous zooplankton) in the food webs. Our meta‐analysis shows that 1) nutrient enrichment has a positive effect on phytoplankton and zooplankton, while fish presence has a positive effect on phytoplankton and a negative effect on zooplankton in the food chains; 2) nutrient enrichment has a positive effect on highly edible algae and small herbivores, but no effect on poorly edible algae, large herbivores and omnivorous zooplankton in the food webs. Planktivorous fish have a positive effect on highly edible algae and small herbivores, a negative effect on large herbivores and omnivorous zooplankton, and no effect on poorly edible algae. Our meta‐analysis confirms that nutrient enrichment and planktivorous fish affect functional groups differentially within trophic levels, revealing important changes in the functioning of food webs. The analysis of fish effects shows the well‐described trophic cascade in the food chain and reveals two trophic cascades in the food web: one transmitted by large herbivores that benefit highly edible phytoplankton, and one transmitted by omnivorous zooplankton that benefit small herbivores. Comparison between the responses of food webs and simple food chains also shows consistent biomass compensation between functional groups within trophic levels.