bluuebunny/crossref_metadata_2025 huggingface dataset:
Consumer behaviour of Brazilian primary school students: findings from focus group interviews
Authors: Fiates Giovanna Medeiros Rataichesck , De Mello Castanho Amboni Renata Dias , Teixeira Evanilda
Published: February 2008

Children worldwide are becoming avid consumers of virtually every type of product and service, which qualifies them as an important primary market. The purpose of this study was to obtain primary data about the consumer behaviour of a group of Brazilian children using a qualitative approach. Twelve focus group interviews were conducted with primary school students (7–10 years, n = 57), and results were processed through content analysis. Many, but not all students, received an allowance, mostly from parents and grandparents. Many students spent the money immediately or after just saving only enough to buy a desired item; others preferred to save their money for the sake of saving it or for a specific future endeavor. Money was spent mainly on food, toys and clothes; sometimes on the impulse of the moment and associated with later guilt. Television was considered a big source of information on new products, but regarded as untrustworthy. When they could not get what they wanted, most children appealed to negotiation strategies; many also reported feeling sad or cross. Results showed a situation of late socialization as consumers, suggesting the children could benefit from consumer education strategies targeted at them.
Effect of ovarian hormones on survival genes in laser captured serotonin neurons from macaques
Authors: Bethea Cynthia L. , Reddy Arubala P.
Published: February 2008

We sought the effect of estradiol (E) and progesterone (P) on survival gene expression in laser captured serotonin neurons and in the dorsal raphe region of monkeys with cDNA array analysis. Spayed rhesus macaques were treated with either placebo, E or E + P via Silastic implant for 1 month prior to killing. First, RNA from a small block of midbrain containing the dorsal raphe was hybridized to Rhesus Gene Chips (n = 3/treatment). There was a significant change in 854 probe sets with E ± P treatment (anova, p < 0.05); however, only 151 probes sets exhibited a twofold or greater change. Twenty‐five genes related to cell survival changed significantly. The expression of vascular endothelial growth factor, superoxide dismutase (SOD1), and the caspase inhibitor, BIRC4, was confirmed with quantitative RT‐PCR. Then, RNA from laser captured serotonin neurons (n = 2/treatment) was hybridized to Rhesus Gene Chips. There was a significant change in 744 probe sets, but 10 493 probe sets exhibited a twofold or greater change. Pivotal changes in apoptosis and cell cycle pathways included twofold or greater increases in SOD1, IκBα, Fas apoptotic inhibitory molecule, fibroblast growth factor‐receptor 2 (FGFR2), neurotrophic tyrosine kinase receptor 2 (NTRK2), phosphoinositide‐3‐kinase (p85 subunit), cyclic AMP dependent protein kinase (PKA) (catalytic subunit), calpain 2, and ataxia telangectasia mutated (ATM). Twofold or greater decreases occurred in TNF receptor interacting serine‐threonine kinase 1 (RIP1), BH3 interacting domain death agonist (BID), apoptotic peptidase activating factor 1 (Apaf1), caspase recruitment domain 8 (CARD8), apoptosis inducing factor (AIF), Diablo and Cyclins A, B, D, and E. The regulation of SOD1, calpain 2, Diablo, and Cyclin D was confirmed with quantitative RT‐PCR (n = 3/treatment). The data indicate that ovarian steroids target the cytokine‐signaling pathway, caspase‐dependent and ‐independent pathways and cell cycle proteins to promote serotonin neuron survival.
Transient adenosine efflux in the rat caudate–putamen
Authors: Cechova Sylvia , Venton B. Jill
Published: February 2008

Adenosine is an endogenous byproduct of metabolism that regulates cerebral blood flow and modulates neurotransmission. Four receptors, with affinities ranging from nanomolar to micromolar, mediate the effects of adenosine. Real‐time measurements are needed to understand the extracellular adenosine concentrations available to activate these receptors. In this study, we measured the subsecond time course of adenosine efflux in the caudate–putamen of anesthetized rats after a 1 s, high‐frequency stimulation of dopamine neurons in the substantia nigra. Fast‐scan cyclic voltammetry at carbon‐fiber microelectrodes was used for simultaneous detection of adenosine and dopamine, which have different oxidation potentials. While dopamine was immediately released after electrical stimulation, adenosine accumulation was slightly delayed and cleared in about 15 seconds. The concentration of adenosine measured after electrical stimulation was 0.94 ± 0.09 μM. An adenosine kinase inhibitor, adenosine transport inhibitor, and a histamine synthetic precursor were used to pharmacologically confirm the identity of the measured substance as adenosine. Adenosine efflux was also correlated with increases in oxygen, which occur because of changes in cerebral blood flow. This study shows that extracellular adenosine transiently increases after short bursts of neuronal activity in concentrations that can activate receptors.
Transcription factor early growth response‐1 induction mediates inflammatory gene expression and brain damage following transient focal ischemia
Authors: Tureyen Kudret , Brooks Nathaniel , Bowen Kellie , Svaren John , Vemuganti Raghu
Published: February 2008

Early growth response‐1 (Egr1) is a sequence‐specific transcription factor (TF) which is induced under hypoxic conditions. We presently report that transient middle cerebral artery occlusion (MCAO) leads to increased expression of Egr1 in the brains of adult mice and rats between 2 h and 5 days of reperfusion with a peak increase of 8–12‐fold at 1 day. When subjected to transient MCAO and 3 days of reperfusion, Egr1−/− mice showed significantly smaller infarcts (by 44.9 ± 8.4%, p < 0.05) and improved neurological function than Egr1+/+ littermates. Following transient MCAO, brains of Egr1−/− mice showed less water accumulation and decreased neutrophil infiltration (by 42 ± 8%, p < 0.05) compared to Egr1+/+ mice. The number of activated microglia/macrophages were also significantly lower (OX42+ cells by 53 ± 9%, p < 0.05 and ED1+ cells by 59 ± 11%) in the post‐ischemic cortex of Egr1−/− mice compared to Egr1+/+ mice. In addition, post‐ischemic inflammatory gene expression was less pronounced in the brains of Egr1−/− mice compared to Egr1+/+ mice. Preventing cerebral Egr1 protein induction with small interference RNAs that target Egr1 decreased inflammatory gene expression and led to smaller infarcts (by 40.2 ± 6.9%, p < 0.05) and reduced neurological deficits in rats subjected to transient MCAO. Conversely, transient MCAO following adenoviral‐mediated Egr1 over‐expression exacerbated the infarct volume (by 29 ± 5.3%, p < 0.05) and worsened the neurological deficits in rats. These studies indicate Egr1 as a significant contributor of inflammation and neuronal damage after stroke.
N,N‐dimethyl‐thioamphetamine and methyl‐thioamphetamine, two non‐neurotoxic substrates of 5‐HT transporters, have scantin vitroefficacy for the induction of transporter‐mediated 5‐HT release and currents
Authors: Gobbi Marco , Funicello Marcella , Gerstbrein Klaus , Holy Marion , Moya Pablo R. , Sotomayor Ramón , Forray María Inés , Gysling Katia , Paluzzi Silvio , Bonanno Giambattista , Reyes‐Parada Miguel , Sitte Harald H. , Mennini Tiziana
Published: February 2008

We studied two non‐neurotoxic amphetamine derivatives (methyl‐thioamphetamine, MTA andN,N‐dimethylMTA, DMMTA) interacting with serotonin (5‐HT) transporters (SERTs) with affinities comparable to that ofp‐Cl‐amphetamine (pCA). The rank order for their maximal effects in inducing both [3H]5‐HT release from rat brain synaptosomes or hSERT‐expressing HEK‐293 cells, and currents in hSERT‐expressing oocytes, was pCA » MTA ≥ DMMTA. A correlation between drug‐induced release and currents is also strengthened by the similar bell shape of the dose–response curves. Release experiments indicated that MTA and DMMTA are SERT substrates although MTA is taken up by HEK‐293 cells with aVmax40% lower than pCA. The weak effects of MTA and DMMTAin vitromight therefore be due to their properties as ‘partial substrates’ on the mechanisms, other than translocation, responsible for currents and/or release. After either local or systemicin vivoadministration, MTA and DMMTA release 5‐HT in a manner comparable to pCA. These findings confirm that the neurotoxic properties of some amphetamine derivatives are independent of their 5‐HT‐releasing activityin vivo. It is worth noting that only those amphetamine derivatives with high efficiency in inducing 5‐HT release and currentsin vitrohave neurotoxic properties.
Docosahexaenoic acid synthesis from n‐3 fatty acid precursors in rat hippocampal neurons
Authors: Kaduce Terry L. , Chen Yucui , Hell Johannes W. , Spector Arthur A.
Published: February 2008

Docosahexaenoic acid (DHA), the most abundant n‐3 polyunsaturated fatty acid in the brain, has important functions in the hippocampus. To better understand essential fatty acid homeostasis in this region of the brain, we investigated the contributions of n‐3 fatty acid precursors in supplying hippocampal neurons with DHA. Primary cultures of rat hippocampal neurons incorporated radiolabeled 18‐, 20‐, 22‐, and 24‐carbon n‐3 fatty acid and converted some of the uptake to DHA, but the amounts produced from either [1‐14C]α‐linolenic or [1‐14C]eicosapentaenoic acid were considerably less than the amounts incorporated when the cultures were incubated with [1‐14C]22:6n‐3. Most of the [1‐14C]22:6n‐3 uptake was incorporated into phospholipids, primarily ethanolamine phosphoglycerides. Additional studies demonstrated that the neurons converted [1‐14C]linoleic acid to arachidonic acid, the main n‐6 fatty acid in the brain. These findings differ from previous results indicating that cerebral and cerebellar neurons cannot convert polyunsaturated fatty acid precursors to DHA or arachidonic acid. Fatty acid compositional analysis demonstrated that the hippocampal neurons contained only 1.1–2.5 mol% DHA under the usual low‐DHA culture conditions. The relatively low‐DHA content suggests that some responses obtained with these cultures may not be representative of neuronal function in the brain.
Ischemic post‐conditioning protects brain and reduces inflammation in a rat model of focal cerebral ischemia/reperfusion
Authors: Xing Bianzhi , Chen Hui , Zhang Min , Zhao Dongming , Jiang Rui , Liu Xiuheng , Zhang Suming
Published: February 2008

Ischemic post‐conditioning (Post‐cond) is a phenomenon in which intermittent interruptions of blood flow in the early phase of reperfusion can protect organ from ischemia/reperfusion (I/R) injury. Recent studies demonstrated ischemic Post‐cond reduced infarct size in cerebral I/R injury. However, the molecular mechanisms underlying this phenomenon are not completely understood. As inflammation is known to be detrimental to the neurological outcome during the acute phase after stroke, we investigated whether ischemic Post‐cond played its protective role in preventing post‐ischemic inflammation in the rat middle cerebral artery occlusion model. Rats were treated with ischemic Post‐cond after 60 min of occlusion (beginning of reperfusion). The infarct volume and myeloperoxidase activity were assessed at 24 h. The lipid peroxidation levels was evaluated by malondialdehyde assay and the expressions of interleukin‐1β, tumor necrosis factor‐α, and intercellular adhesion molecule 1 were studied by RT‐PCR or western blotting. Ischemic Post‐cond decreased myeloperoxidase activity and expressions of interleukin‐1β, tumor necrosis factor‐α, and intercellular adhesion molecule 1. Ischemic Post‐cond also reduced infarct volume and lipid peroxidation levels. These findings indicated that ischemic Post‐cond may be a promising neuroprotective approach for focal cerebral I/R injury and it is achieved, at least in part, by the inhibition of inflammation.
Parkin protects against tyrosinase‐mediated dopamine neurotoxicity by suppressing stress‐activated protein kinase pathways
Authors: Hasegawa Takafumi , Treis Angela , Patenge Nadja , Fiesel Fabienne C. , Springer Wolfdieter , Kahle Philipp J.
Published: February 2008

Parkinson’s disease (PD) motor symptoms are caused by degeneration of nigrostriatal dopaminergic (DAergic) neurons. The most common causes of hereditary PD are mutations in the PARKIN gene. The ubiquitin ligase parkin has been shown to mediate neuroprotection in cell culture and in vivo, but the molecular mechanisms are not well understood. We investigated the effects of parkin in a human SH‐SY5Y neuroblastoma cell culture model of PD, in which transcriptional induction of the enzyme tyrosinase causes a neurotoxic overproduction of cellular DA and its oxidative metabolites. Tyrosinase induction caused formation of reactive oxygen species in the cytosol and mitochondria, and neurotoxicity via activation of apoptotic stress‐activated protein kinases and caspase 3. Stable transfection of wild‐type parkin suppressed tyrosinase‐induced apoptosis, and PD‐associated mutations abolished the neuroprotective effect of parkin. Expression of wild‐type parkin did not affect reactive oxygen species production, but attenuated the tyrosinase‐induced activation of both c‐Jun N‐terminal kinase and p38 mitogen‐activated protein kinase as well as their cognate mitogen‐activated protein kinase kinases. PD‐associated mutations differentially affected the anti‐apoptotic signaling of parkin. Thus, parkin contributes to DAergic neuroprotection by suppression of apoptotic stress‐activated protein kinase pathways.
A role for p53 in the regulation of lysosomal permeability by Δ9‐tetrahydrocannabinol in rat cortical neurones: implications for neurodegeneration
Authors: Gowran Aoife , Campbell Veronica A.
Published: February 2008

The psychoactive ingredient of marijuana, Δ9‐tetrahydrocannabinol (Δ9‐THC), can evoke apoptosis in cultured cortical neurones. Whilst the intracellular mechanisms responsible for this apoptotic pathway remain to be fully elucidated, we have recently identified a role for the CB1 type of cannabinoid (CB) receptor and the tumour suppressor protein, p53. In the current study, we demonstrate the Δ9‐THC promotes a significant increase in lysosomal permeability in a dose‐ and time‐dependent manner. The increase in lysosomal permeability was blocked by the CB1 receptor antagonist, AM251. Δ9‐THC increased the localization of phospho‐p53Ser15 at the lysosome and stimulated the release of the lysosomal cathepsin enzyme, cathepsin‐D, into the cytosol. The p53 inhibitor, pifithrin‐α and small interfering RNA‐mediated knockdown of p53 prevented the Δ9‐THC‐mediated increase in lysosomal permeability. Furthermore, the Δ9‐THC ‐mediated induction of apoptosis was abrogated by a cell‐permeable cathepsin‐D inhibitor (10 μM). Thus, the study demonstrates that Δ9‐THC impacts on the lysosomal system, via p53, to evoke lysosomal instability as an early event in the apoptotic cascade. This provides evidence for a novel link between the CB1 receptor and the lysosomal branch of the apoptotic pathway which is crucial in regulating neuronal viability following exposure to Δ9‐THC.
Developmentally regulated alternative splicing of densin modulates protein–protein interaction and subcellular localization
Authors: Jiao Yuxia , Robison A. J. , Bass Martha A. , Colbran Roger J.
Published: February 2008

Densin is a member of the leucine‐rich repeat (LRR) and PDZ domain (LAP) protein family that binds several signaling molecules via its C‐terminal domains, including calcium/calmodulin‐dependent protein kinase II (CaMKII). In this study, we identify several novel mRNA splice variants of densin that are differentially expressed during development. The novel variants share the LRR domain but are either prematurely truncated or contain internal deletions relative to mature variants of the protein (180 kDa), thus removing key protein–protein interaction domains. For example, CaMKIIα coimmunoprecipitates with densin splice variants containing an intact C‐terminal domain from lysates of transfected HEK293 cells, but not with variants that only contain N‐terminal domains. Immunoblot analyses using antibodies to peptide epitopes in the N‐ and C‐ terminal domains of densin are consistent with developmental regulation of splice variant expression in brain. Moreover, putative splice variants display different subcellular fractionation patterns in brain extracts. Expression of green fluorescent protein (GFP)‐fused densin splice variants in HEK293 cells shows that the LRR domain can target densin to a plasma membrane‐associated compartment, but that the splice variants are differentially localized and have potentially distinct effects on cell morphology. In combination, these data show that densin splice variants have distinct functional characteristics suggesting multiple roles during neuronal development.
The glutamate transporter GLT1b interacts with the scaffold protein PSD‐95
Authors: González‐González Inmaculada M. , García‐Tardón Noemí , Cubelos Beatriz , Giménez Cecilio , Zafra Francisco
Published: February 2008

The glutamate transporter (GLT1) regulates glutamate concentrations in glutamatergic synapses and it is expressed in at least two isoforms, GLT1a and GLT1b. In this work, we show that the C‐terminus of GLT1b is able to interact with the PDZ domains of a number of proteins. Notably, one of them might be the scaffold protein post‐synaptic density (PSD‐95). GLT1b formed co‐immunoprecipitable complexes with PSD‐95 in solubilizated rat brain extracts, complexes that also contained NMDA receptors. Co‐transfection of GLT1b, PSD‐95, and NMDA receptor subunits in heterologous expression systems recapitulated in vitro the interactions among these proteins that had been observed in the rat brain extracts and revealed the importance of the GLT1b C‐terminal PDZ binding motif in tethering this transporter to PSD‐95. Significantly, co‐expression of GLT1b and PSD‐95 increased the Vmax of the transporter by decreasing the rate of GLT1b endocytosis. Moreover, GLT1b transfected into primary cultured neurons or glia formed protein clusters that co‐localized with co‐transfected PSD‐95, clusters that in these neurons accumulated preferentially in dendritic spines. We hypothesize that the GLT1b/PSD‐95 interaction, characterized here in vitro, might anchor this transporter close to the post‐synaptic glutamate receptors, thereby permitting the fine regulation of glutamate concentrations in this microenvironment. This tight association might also facilitate the regulation of GLT1b through the signaling pathways initiated by the activation of glutamate receptors.
Like a shadow – on becoming a stroke victim's relative
Authors: Wallengren Catarina , Friberg Febe , Segesten Kerstin
Published: February 2008

Stroke is the third leading cause of death and disability in the western world. Given the ageing population in Sweden, the number of people suffering from stroke is likely to increase in the future. Stroke alters the lives of both patients and their relatives. Few studies have explored first time affected relatives’ experiences of suddenly becoming a relative to a stroke victim, before the relatives decide whether or not to become informal carers. The aim of this study was to illuminate the meaning of going from being just a relative to gradually becoming a relative to a stroke victim from the time of the stroke event and the first weeks on. Sixteen relatives were interviewed about their experiences regarding what it was like to become a relative of a stroke victim from the time of the onset of the illness to the day of the interview. Using a phenomenological hermeneutic method, two essential main themes emerged to describe the relatives’ experience: (i) being in chaos and (ii) searching for order in chaos. The findings reveal that relatives reach a ‘turning point’. The ‘turning point’ arises when the relatives stay close to the stroke victim, get aware of their own strength and actively seek out caregivers to restore order and stability to the chaotic situation they are in. At the ‘turning point’, the relatives start their journey to restore order and stability of the chaotic life situation. Caregivers need to pay more attention and be more sensitive to relatives to increase their possibilities of restoring order and stability in their lives. The results contribute to facilitating the caregivers’ work by showing that the time is ripe for initiating pedagogical work when the relatives start to mobilise themselves.
Psychological functioning and predictors of father–infant relationship in IVF fathers and controls
Authors: Hjelmstedt Anna , Collins Aila
Published: February 2008

The psychological functioning of fathers with children born after in vitro fertilization (IVF) has received little attention. Among men in general, little is known about predictors of early father–infant relationship (here also defined as attachment). The first aim was to compare IVF fathers and control fathers regarding personality traits, state anxiety, depressive symptoms and early father–infant attachment. The second aim was to assess whether early father–infant relationship is explained by the father’s prenatal relationship with the unborn infant, his personality traits, state anxiety and symptoms of depression. Fifty‐three IVF fathers and 36 controls filled in self‐rating scales measuring father–infant attachment, personality, anxiety and symptoms of depression at 2 months postpartum. At gestational week 26 their prenatal relationship to the unborn infant was assessed. It was found that IVF fathers rated more somatic and psychic anxiety, indirect aggression and less assertiveness. They were as strongly attached to their infant as the controls. Fathers, who had rated higher attachment to their unborn infant during pregnancy, who were less anxious, more assertive and less irritable, were more attached to their infants than men who had been less attached to their unborn infants and who were more anxious, less assertive and more irritable. In conclusion, although IVF fathers are as strongly attached to their infants as other fathers, they may benefit from emotional support as they have elevated levels of anxiety proneness and indirect aggression. It is important to pay attention during pregnancy to fathers who have a less optimal attachment to their unborn infant and who have high levels of anxiety and irritability, as those three factors are related to a weak emotional father–infant relationship.
Experience of being the spouse/cohabitant of a person with bipolar affective disorder: a cumulative process over time
Authors: Tranvåg Oscar , Kristoffersen Kjell
Published: February 2008

The aim of the study was to identify and describe spouses’/cohabitants’ experiences of living with a partner with bipolar affective disorder over time. Qualitative research interviews were conducted with eight spouses/cohabitants. Transcribed interviews were analysed structurally based on Ricoeur’s phenomenological hermeneutics as described by Lindseth and Norberg. The participants’ shared lives ranged from 6 to 51 years, and the study found three major aspects that characterized their experience along this time‐dimension; experience formed part of a cumulative process containing up to 14 experiences. Each experience created a preunderstanding that affected how subsequent experiences were perceived, and mastered. These three major aspects had a reciprocal influence on the following 14 experiences over time: Fear and the incomprehensible. Accusations. Self‐doubt and doubt about own powers of judgement. Care and information vs. being overlooked or turned away by health personnel. Stigmatization and loss of social network. Uncertainty, powerlessness and hope. Loneliness. Anger and despair. The persistent threat. Own health problems. Grief over loss. Dawning acceptance. Reconciliation. New hope. A theoretical understanding using gestalt therapy theory suggests that burdensome experience can be seen as an inner imbalance in the spouse/cohabitant when she/he cannot find meaning in their experiences. When only parts of the whole are perceived, an incomplete gestalt is formed in the person’s lived‐experience that counteracts the equilibrium of the organism. Insight and meaning can protect them against burdensome experiences and nurses can empower them through care, health‐promoting education and guidance. Nursing research should develop methods of education and guidance sensitive enough to help each spouse/cohabitant, regardless of where they are in their cumulative process.
Coping strategies and styles of family carers of persons with enduring mental illness: a mixed methods analysis
Authors: Kartalova‐O’Doherty Yulia , Doherty Donna Tedstone
Published: February 2008

A qualitative exploratory study investigated the experiences and needs of family carers of persons with enduring mental illness in Ireland. The current mixed‐methods secondary study used content analysis and statistical procedures to identify and explore the coping strategies emerging from the original interviews. The majority of family carers reported use of active behavioural coping strategies, sometimes combined with active cognitive or avoidance strategies. The percentage of cares reporting use of active cognitive strategies was the lowest among those whose ill relative lived in their home, and the highest among those whose relative lived independently. Participants with identified active cognitive strategies often reported that their relative was employed or in training. Participants who reported use of avoidance strategies were significantly younger than participants who did not report use of such strategies. The lowest percentage of avoidance strategies was among participants whose ill relative lived independently, whereas the highest was among carers whose relative lived in their home. The findings of this study highlight the importance of a contextual approach to studying coping styles and processes. Further research questions and methodological implications are discussed.
Advances in vertebrate aging research 2007
Authors: Austad Steven
Published: February 2008

Among this year's highlights in vertebrate aging research, we find a study in which, contrary to the oxidative stress hypothesis of aging, reduced expression of a major cellular antioxidant, glutathione peroxidase 4, led to a small increase in mouse lifespan. By contrast, a large comparative proteomic analysis discovered a remarkably robust and previous unsuspected inverse association between species lifespan and relative frequency of cysteine residues in mitochondrially encoded respiratory chain proteins only, which the authors attribute to cysteine's ease of oxidation. Another study evaluated more cleanly than any previous work the hypothesis that blood glucose concentration is a key mediator of aging, and concluded that it wasn't. Several new mouse longevity mutants were also reported this year, some (PAPP‐A, IRS‐1, and IRS‐2 knockouts) supporting previous work on the importance of insulin/insulin‐like growth factor‐1 signaling and aging. However, there were inconsistencies between laboratories in some of the results, which merit further investigation. Also, somewhat inconsistent with these findings, over‐expression of insulin‐like growth factor‐1 in heart only lengthened life. From a completely new direction, type 5 adenylyl cyclase knockout mice were observed to live more than 30% longer than controls. Finally, a new program for evaluating potential pharmaceutical interventions in aging and longevity made its appearance, and is notable at this point chiefly for the excellence of its experimental design. A similar program for the disinterested evaluation of reported longevity mutations in mice would be a service to the community of vertebrate aging researchers.
Left ventricular end‐diastolic geometrical adjustments during exercise in endurance athletes
Authors: Henriksen Egil , Sundstedt Milena , Hedberg Pär
Published: February 2008

The increase in left ventricular (LV) end‐diastolic volume has recently been shown to explain more than 70% of the increase in stroke volume during upright exercise in endurance athletes. As the end‐diastolic volume enhancement not could be explained by an increase in axial cavity length an augmentation in LV short‐axis diameters is to be expected. To investigate LV end‐diastolic geometrical alterations during exercise, 15 endurance athletes were examined using contrast exercise echocardiography. LV end‐diastolic short‐axis diameters were made from apical views at several LV cavity levels. From upright rest to upright exercise the LV end‐diastolic internal cavity measurements increased significantly. During exercise, the LV cavity became geometrically more spherical with the largest increase in the LV end‐diastolic short‐axis cavity diameters in the mid and apical parts of the left ventricle. The LV internal long axis showed significant increase from rest to exercise but the absolute increase was small.
Effects of local α2‐adrenergic receptor blockade on adipose tissue lipolysis during prolonged systemic adrenaline infusion in normal man
Authors: Simonsen Lene , Enevoldsen Lotte H. , Stallknecht Bente , Bülow Jens
Published: February 2008

During prolonged adrenaline infusion, lipolysis peaks within 30 min and thereafter tends to decline, and we hypothesized that the stimulation of local adipose tissue α2‐adrenergic receptors accounts for this decline. The lipolytic effect of a prolonged intravenous adrenaline infusion combined with local infusion of the α2‐blocker phentolamine in superficial and deep abdominal subcutaneous adipose tissue and in preperitoneal adipose tissue was studied in seven healthy subjects. The interstitial glycerol concentration in the three adipose tissue depots was measured by the microdialysis method. Regional adipose tissue blood flow was measured by the 133Xe clearance technique. Regional glycerol output (lipolytic rate) was calculated from these measurements and simultaneous measurements of arterial glycerol concentrations. Adrenaline infusion increased lipolysis in all three depots (data previously published). Phentolamine infusion did not augment lipolysis in the subcutaneous depots while it increased the lipolytic rate in the preperitoneal depot. It is concluded that α2‐adrenergic receptors do not have a significant effect on subcutaneous adipose tissue lipolysis during high circulating adrenaline concentrations, and the decrease in lipolysis in subcutaneous adipose tissue under prolonged adrenaline stimulation is thus not attributed to α2‐adrenergic receptor inhibition of lipolysis. However, in the preperitoneal adipose tissue depot, α2‐adrenergic receptor tone plays a role for the lipolytic rate obtained during prolonged adrenaline stimulation.
Bone mineral density and single photon emission computed tomography changes after total knee arthroplasty: a 2‐year follow‐up study
Authors: Soininvaara Tarja , Nikola Tua , Vanninen Esko , Miettinen Hannu , Kröger Heikki
Published: February 2008

Dual X‐ray absorptionmetry (DXA) provides a highly reproducible method for quantitative analysis and monitoring periprosthetic bone mineral density (BMD) after total knee arthroplasty (TKA). Single photon emission computed tomography (SPECT) with bone avid radiopharmaceuticals reflects bone metabolic activity and circulation. We combined information from DXA and SPECT to assess the evaluation of the dynamic balance between BMD and bone turnover.

Sixteen patients underwent serial DXA (Lunar Expert XL) and 99mTc‐methylene diphosphonate SPECT measurements until 2 years after TKA. A rapid bone loss, up to 25·5%, was detected in femur during the first six postoperative months. However, tibial periprosthetic BMD remained close to baseline. There was a significant correlation between 12‐month SPECT uptake and preceding BMD change in medial tibia (r = 0·5, P = 0·044). At 12 months, SPECT uptakes in the operated knee were notably higher compared with those of the control knee. SPECT uptakes showed statistically significant decreases from 12 months to 24 months, while SPECT uptake in the control knee remained stable. In tibia, the results are more complex; referring that increased bone remodelling is continuing below the tibial tray. Furthermore, femoral diaphyseal uptake remained elevated, while corresponding tibial uptake had levelled off at 2 years.

Increased SPECT uptake during the first 2 years after uncomplicated TKA results most likely from normal postoperative bone remodelling. Levelling of SPECT uptake may indicate a new balance between bone loss and regain.
IGF‐1, IGFBP‐3, VEGF and MMP‐9 levels and their potential relationship with renal functions in patients with compensatory renal growth
Authors: Yildiz Bilal , Kural Nurdan , Colak Omer , Ak Ilknur , Akcar Nevbahar
Published: February 2008

Background:  Mechanisms of compensatory renal growth (CRG) still remain a mystery. Various growth factors, including growth hormone, insulin‐like growth factor‐1 (IGF‐1) have been implicated in different forms of CRG.

Aims:  To investigate the serum levels of IGF‐1, vascular endothelial growth factor (VEGF – role in vascular remodelling), matrix metalloproteinase‐9 (MMP‐9 – essential for normal nephrogenesis) and correlation of renal function in patients with unilateral nephrectomized, agenesis and hypoplasic kidney.

Methods:  Thirty patients were included in this study. In group I, there were 10 patients with unilateral nephrectomy, while in group II, there were 10 patients with unilateral agenesis. As for group III, there were 10 patients with unilateral hypoplastic kidney. The serum levels of IGF‐1, IGF‐binding protein‐3 (IGFBP‐3), VEGF and MMP‐9 were studied in all the cases. Clearance of creatinin (Ccr) and protein excretion were examined in the 24 h urine. CRG was determined with ultrasonography and scintigraphy. Twenty‐six control subjects were also studied.

Results:  The levels of IGF‐1, IGFBP‐3, VEGF and MMP‐9 were significantly higher in patients than in the control subjects (P < 0·001). Ccr and protein excretion levels were different in study groups than in those of the control group (P < 0·01). There were positive correlations between the serum levels of IGF‐1 with IGFBP‐3; IGF‐1 with MMP‐9; IGFBP‐3 with MMP‐9 (r = 0·825, P = 0·0001; P < 0·001 r = 0·611; P < 0·001 r = 0·585, respectively). There were negative correlations between GFR and the serum levels of IGF‐1, IGFBP‐3 and MMP‐9 (P < 0·01 r = −0·708; P = 0·002 r = −0·803; P < 0·05 r = −0·442, respectively). Furthermore, there were positive correlations between proteinuria and the serum levels of IGF‐1, IGFBP‐3 and MMP‐9 (P = 0·039 r = 0·600; P < 0·05 r = 0·456; P < 0·05 r = 0·424).

Conclusions:  Increased IGF‐1, IGFBP‐3, VEGF and MMP‐9 were observed in CRG in the follow‐up period. IGF‐1 and MMP‐9 seemed to have increased in patients with CRG in defiance of the development of fibrosis. Moreover, IGF‐1 and MMP‐9 seem to be associated with reduced renal function and proteinuria.
Subtle changes in ADMA andl‐arginine concentrations in normal pregnancies are unlikely to account for pregnancy‐related increased flow‐mediated dilatation
Authors: Saarelainen Heli , Valtonen Pirjo , Punnonen Kari , Laitinen Tomi , Raitakari Olli T. , Juonala Markus , Heiskanen Nonna , Lyyra‐Laitinen Tiina , Viikari Jorma S. A. , Vanninen Esko , Heinonen Seppo
Published: February 2008

Background: Our objective was to investigate whether serum concentrations of asymmetric dimethylarginine (ADMA) orl‐arginine correlate to hyperlipidemia or endothelial function in normal pregnancy compared with the non‐pregnant subjects.

Methods and results: As a part of population‐based, prospective cohort Cardiovascular Risk in Young Finns study conducted in Finland we examined 57 pregnant Finnish women throughout gestation and 62 control women matched for age and smoking. Serum glucose, triglycerides (TG), total cholesterol (TC), low‐density cholesterol (LDL‐C), high‐density cholesterol (HDL‐C) and ADMA, symmetric dimethylarginine (SDMA) andl‐arginine were determined concomitantly with endothelium‐dependent brachial artery flow‐mediated dilation (FMD), measured by ultrasound. All serum lipid concentrations were significantly higher in pregnant women than in non‐pregnant women (P < 0·001 for each). The mean serum ADMA concentration in pregnant women was significantly lower compared with the non‐pregnant controls (0·513 μmol l−1 ± 0·0593 versus 0·577 μmol l−1 ± 0·0710,P < 0·001). Lowered ADMA concentrations did not correlate statistically to FMD in these healthy pregnant women but FMD was enhanced towards the end of pregnancy.

Conclusions: ADMA andl‐arginine concentrations fall in normal pregnancy despite marked hypercholesterolemia. Endothelium‐dependent vasodilation is enhanced in normal pregnancy but is not statistically correlated to maternal serum ADMA orl‐arginine concentrations.
Reliability of isokinetic strength imbalance ratios measured using the Cybex NORM dynamometer
Authors: Impellizzeri Franco M. , Bizzini Mario , Rampinini Ermanno , Cereda Ferdinando , Maffiuletti Nicola A.
Published: February 2008

The main aim of this study was to examine the absolute and relative reliability of some commonly used strength imbalance indices such as concentric hamstring‐to‐concentric quadriceps ratio, eccentric hamstring‐to‐concentric quadriceps ratio and bilateral concentric and eccentric strength ratios. An additional aim was to examine the reliability of the peak torque and work of the knee extensor and flexor muscles measured using the Cybex NORM dynamometer. Eighteen physically active healthy subjects (mean ± standard deviation, age 23 ± 3 years, height 176 ± 5 cm, body mass 74 ± 8 kg) were tested three times with 96 h between sessions. Peak torque, average work, unilateral and bilateral ratios were determined at 60, 120, 180 and −60° s−1. Low (0·34) to moderate (0·87) relative reliability (intraclass correlation coefficient, ICC) was found for strength imbalance ratios with eccentric hamstring‐to‐concentric quadriceps ratio showing the greater ICC (>0·80). High ICC values (0·90–0·98) were found for peak torque and average work. Absolute reliability (standard error of measurement) ranged from 3·2% to 8·7% for strength imbalance ratios and from 4·3% to 7·7% for peak torque and average work measurements. This study established the reliability of the most common strength imbalance ratios and of absolute isokinetic muscle strength assessed using the Cybex NORM.
Health‐related aspects of objectively measured daily physical activity in children
Authors: Dencker Magnus , Andersen Lars Bo
Published: February 2008

It is well established that physical inactivity in adults is associated with increased mortality and morbidity. Whether daily physical activity level is related to risk factors for cardiovascular disease (CVD) in children has been debated. Furthermore, objective data on the habitual daily physical activity in children have at large been scarce in the literature. The main reason for this is the fact that daily physical activity is very difficult to measure in children. In recent years, a new device, the accelerometer, has emerged as a frequently used instrument for the measurement of daily physical activity. This review summarizes recently published studies that have used accelerometers to measure daily physical activity in children and related activity data to known risk factors for CVD.
Coma and respiratory failure due to moxidectin intoxication in a dog
Authors: Gallagher Alexander E. , Grant David C. , Noftsinger Maureen N.
Published: February 2008

Objective:To describe the clinical consequences following ingestion by a dog of a moxidectin‐containing equine deworming product. Few reports exist concerning the treatment and outcome of severe moxidectin toxicity. Treatment, known factors influencing intoxication, and prognosis are reviewed.

Case summary:A 10‐month‐old female Border Collie ingested an unknown quantity of a moxidectin‐containing equine deworming product several hours before presentation. Severe neurological signs subsequently developed and included: ataxia, seizures, coma, and respiratory failure. The dog was treated with supportive care including intravenous fluids, activated charcoal, and positive pressure ventilation. Normal spontaneous respiration returned in 34 hours and the patient was discharged 58 hours after ingestion. Full recovery occurred within 1 week of intoxication.

New information provided:This report describes moxidectin intoxication and associated respiratory failure in a dog that required mechanical ventilation. The dog's recovery was rapid. Despite severity of signs, the prognosis for patients with moxidectin intoxication is good with appropriate supportive care.
Clinical evaluation and management of hemoperitoneum in dogs
Authors: Herold Lee V. , Devey Jennifer J. , Kirby Rebecca , Rudloff Elke
Published: February 2008

Objective:Review the clinical presentation, assessment, resuscitation, and medical and surgical management of dogs with hemoperitoneum.

Etiology:Hemoperitoneum is defined as free intra‐abdominal hemorrhage. Hemoperitoneum occurs from traumatic and nontraumatic causes. Common etiologies include atraumatic rupture of intra‐abdominal masses, coagulopathies, as well as blunt, and penetrating trauma to the abdomen.

Diagnosis:Definitive diagnosis of hemoperitoneum entails demonstration of free intra‐abdominal blood via paracentesis or diagnostic peritoneal lavage. Imaging and other diagnostic tests including coagulation studies may help to determine underlying causes of hemoperitoneum or concurrent organ dysfunction.

Therapy:Goals of therapy for patients with hemoperitoneum include maintenance and restoration of effective circulating volume, maintenance and restoration of oxygen‐carrying capacity, and arrest of hemorrhage. These goals can be achieved via fluid resuscitation, administration of blood products or hemoglobin‐based oxygen carriers, as well as application of abdominal counterpressure, and surgical intervention. Surgery usually is required for bleeding intra‐abdominal neoplasms. Emergency surgery is recommended for hemorrhaging patients with penetrating trauma, gastric dilatation and volvulus, bleeding cysts, liver lobe torsion, splenic torsion, and any other condition resulting in organ ischemia.

Prognosis:Prognosis in patients with hemoperitoneum may depend on the underlying cause and concurrent injuries.
The pharmacologic spectrum of furosemide
Authors: Abbott Lisa M. , Kovacic Jan
Published: February 2008

Objective: To review the clinical spectrum and mechanisms of action of furosemide in human and small animal veterinary patients.

Data sources: Review of human and veterinary literature.

Data synthesis: Furosemide is used primarily for its properties as a loop diuretic; however, it has many other actions that may be clinically applicable. Furosemide has a vasodilatory effect that precedes diuresis that may confer its immediate benefit in patients with volume overload. Furosemide can be inhaled to relieve dyspnea in patients with bronchospasm. Furosemide also shows promise as an adjunct to antiseizure therapy to help control epilepsy, status epilepticus, and acute ischemic damage related to seizures. It has activity as an antioxidant, iodine depletive, and may increase thoracic lymph duct flow. Reported furosemide side effects include altered drug metabolism, electrolyte depletion, ototoxicity, mucociliary impairment, endocrine and exocrine pancreatic effects, delayed wound healing, sulfonamide toxicity, and thyroid binding interference. It is worthwhile to consider the implications of these effects when using furosemide either alone or in combination with other drugs.

Conclusions: Despite the research in animal models that demonstrates a wide spectrum of pharmacologic activity, furosemide has not been widely recognized or used clinically in veterinary medicine except as a loop diuretic.
Electrocardiographic assessment of hyperkalemia in dogs and cats
Authors: Tag Tanya L. , Day Thomas K.
Published: February 2008

Objective:To determine if electrocardiogram (ECG) changes induced by hyperkalemia in clinical patients correspond with previously reported changes in experimental animals.

Design:Prospective clinical study.

Setting:Two private practice 24‐hour emergency and critical care facilities.

Animals:Fifteen dogs and 22 cats with serum potassium levels >5.5 mEq/L.

Interventions:None.

Measurements:The following data were collected when hyperkalemia was documented: ECG (n=37), sodium and chloride (mEq/L) (n=35), total magnesium (mg/dL) (n=18), total calcium (mg/dL) (n=30), and venous pH (n=18). Animals were divided into five groups based on severity of hyperkalemia and ECG interpretation included rate, rhythm and P‐QRS‐T evaluation.

Main Results:Twenty‐two of 37 (59%) of the ECGs were normal or revealed abnormalities that have not been previously described in conjunction with hyperkalemia. In dogs, there was no correlation (r=0) between potassium blood levels and heart rate (n=15). There was weak correlation (r=0.40;P=0.06) between potassium blood levels and heart rate in cats (n=22). The correlation was stronger (r=0.64;P<0.05) when data were compared in cats with serum potassium level >8.5 mEq/L (Groups 4 and Group 5;n=11).

Conclusions:ECGs obtained from ill dogs and cats with hyperkalemia are inconsistent with ECGs from experimentally induced hyperkalemia. It is difficult to determine the clinical relevance of heart rate differences between cats with serum potassium levels >8.5 mEq/L and animals with experimentally induced hyperkalemia; this may be due to the presence of other biochemical abnormalities in diseased animals.
Temporary transvenous cardiac pacing in a dog with diltiazem intoxication
Authors: Syring Rebecca S. , Costello Merilee F. , Poppenga Robert H.
Published: February 2008

Objective: This case report presents the clinical findings of a dog with diltiazem intoxication and the utilization of temporary transvenous pacing for management of high‐grade second‐degree atrioventricular (AV) block with associated bradycardia and hypotension.

Case summary: A nine‐year‐old spayed female Basset Hound, who ingested between 95 and 109 mg/kg of sustained‐release diltiazem exhibited clinical signs of cardiac arrhythmias, bradycardia, hypotension, mental depression and gastrointestinal (GI) upset. Bradycardia was present initially, then was followed by high‐grade second‐degree AV block with ventricular escape. Traditional medications to treat calcium channel blocker (CCB) intoxication, including atropine, calcium gluconate, dopamine and glucagon were initially successful in managing the cardiac rhythm disturbances and hypotension. Twenty‐two hours post‐ingestion, however, the dog became refractory to these medications following sedation for GI decontamination and a temporary transvenous pacemaker was placed. The dog was paced for 19 hours. Transvenous pacing effectively increased heart rate, which increased blood pressure into an acceptable range. The dog was successfully discharged from the hospital following treatment.

New or unique information provided: The use of a temporary pacemaker should be considered an acceptable treatment for bradycardia, AV block and hypotension associated with CCB intoxication when conventional medical therapy fails.