bluuebunny/crossref_metadata_2025 huggingface dataset:
Gis-based niche models reveal unifying climatic mechanisms that maintain the location of avian hybrid zones in a North American suture zone
Authors: Swenson N. G.
Published: January 2006

The existence of suture zones in North America has recently been verified, yet the environmental factors responsible for the maintenance of their structure and position have remained undetermined. The Great Plains suture zone in the US is perhaps the most significant and broadly studied in North America. Numerous avian hybrid zones that cluster in this region have been extensively studied over the last half-century. A primary result of this work is that exogenous factors present in this region have promoted and maintained avian species divergence. Yet, to date the variables most important in the generation and the clustered positioning of these hybrid zones in relation to one another have not been determined. The present study aims to advance our understanding of this North American suture zone by using niche modelling to quantify which environmental variables are most important in its formation and maintenance. Through the generation of fundamental niches for four hybrids and their parental species, similarities linking the hybrid zones were uncovered. The results show that temperature holds this suture zone in position and also suggest that temperature played a primary role in promoting niche differentiation among these sister species pairs during Pleistocene glacial cycles.
Lawsonia intracellularisProliferative Enteropathy in a Filly
Authors: Wuersch K. , Huessy D. , Koch C. , Oevermann A.
Published: January 2006

Proliferative enteropathy (PE) caused by the obligate intracellular bacteriumLawsonia intracellularisis a disease of high economic impact in swine worldwide. In most other species the disease occurs as a sporadic infection. This paper reports a PE caused byL. intracellularisin a 9‐month‐old Pura Raza Española filly with a history of profuse diarrhoea. Pathological lesions consisted of a severe proliferative enteritis associated with argyrophilic bacteria in the apical cytoplasm of proliferating crypt epithelium. Characteristic PCR products confirmed the presumptive diagnosis ofL. intracellularisinfection. To our knowledge this is the first report of PE in a horse in Europe caused byL. intracellularis.
Pharmacokinetics of a Lidocaine Patch 5% in Dogs
Authors: Weiland L. , Croubels S. , Baert K. , Polis I. , De Backer P. , Gasthuys F.
Published: January 2006

Lidocaine is increasingly used in transdermal drug delivery systems for different pain conditions in human medicine whereby several pharmacokinetic studies have demonstrated minimal systemic absorption in men. In the present study, the pharmacokinetics of a lidocaine patch 5% was studied in six dogs. In the first experiment, one single lidocaine patch was applied for 12 h to the lateral side of the thorax after removing the hair either by clipping or by the application of a depilatory agent, according to a two‐way crossover design. No potential adverse effects induced by the patches were observed in either group. In dogs with clipped hair, a mean peak plasma lidocaine concentration of 62.94 ng/ml was obtained after 10.67 h. In the depilatory group, a mean peak plasma concentration of 103.55 ng/ml was reached after 9.27 h. Significant differences in the AUC0 → ∞, Cmax, ka and T1/2a were noticed between the two groups. No significant differences were found for the elimination parameters and for Tmax. In the second experiment, the patches were applied for 60 h to the clipped skin in order to study the absorption kinetics after a prolonged application period. There, the mean peak lidocaine plasma concentration was 45.18 ng/ml achieved after 24 h and a final concentration of 29.37 ng/ml was obtained at 60 h. In conclusion, all dogs tolerated the transdermal lidocaine patch well. The results of this study suggest that there is an overall minimal absorption from the lidocaine patch. However, the application of a depilatory agent leads to a more rapid and increased absorption of lidocaine.
Echium vulgare and Senecio vulgaris Poisoning in Fighting Bulls
Authors: Moyano M. R. , García A. , Rueda A. , Molina A. M. , Mendez A. , Infante F.
Published: January 2006

An unusual case of poisoning by simultaneous ingestion of Echium vulgare L. and Senecio vulgaris L. in a herd of Spanish fighting bulls is described. Ten animals died from a herd of 700 in an area located in Sierra Norte, Seville (Constantina) in Spain. The interest of this case lies both in the breed affected (this is the first report on fighting bulls) and the lack of information about bovine poisoning by these plants in Spain. Animal samples were obtained from October to March. All the dead animals were 1 year old and had grazed at the farm. The diagnosis was made by determining the plant species and studying its distribution in the pastureland, and also by performing blood analysis of the sick animals in addition to an anatomopathological study of the carcasses. Tuberculosis, brucellosis, salmonellosis, IBR/BVD and also the presence of aflatoxins in the forage were all ruled out.
Fasting‐induced Changes in Ovulation Rate, Plasma Leptin, Gonadotropins, GH, IGF‐I and Insulin Concentrations During Oestrus in Ewes
Authors: Kosior‐Korzecka U. , Bobowiec R. , Lipecka Cz.
Published: January 2006

The aim of this experiment was to study the changes in the hormonal status and ovulation rate (OR) evoked by starvation during the follicular phase of the oestrous cycle in ewes. To achieve this goal, 12 female crossbreed sheep were synchronized and then half of them were fasted from the 12th to the 16th day of the oestrous cycle. On the 16th day, analysis of hormones and insulin‐like growth factor‐I (IGF‐I) were performed in 10‐min intervals. Then, on the 6th day of the following oestrous cycle, the OR in all ewes was determined by laparoscopy. Fasting reduced significantly (P < 0.05) the OR in ewes (1.25 ± 0.50) in comparison with control (1.75 ± 0.50). The drop in the OR was coincident with a significant (P < 0.001) decrease in the plasma concentration and pulse amplitude of leptin (0.29 ± 0.08 ng/ml versus control 0.53 ± 0.14 ng/ml), the plasma level of luteinizing hormone (LH) (0.19 ± 0.06 IU/l versus 0.25 ± 0.09 IU/l in control; P < 0.05) and the mean frequency of LH pulses (2.0/h versus 2.5/h in control). Fasting resulted also in a significant (P < 0.05) decrease in the plasma concentration and pulse amplitude of follicle stimulating hormone (FSH) in comparison with the control. Simultaneously, a significant (P < 0.001) drop in the IGF‐I concentration in the fasted ewes (4.78 ± 0.91 ng/ml) was found in comparison with control (7.63 ± 1.85 ng/ml). Also the level of insulin were significantly (P < 0.001) lower in the fasted (178.99 ± 39.08 pm/l respectively) than in the control sheep (302.66 ± 49.01 pm/l respectively). Meanwhile, a double increase in the growth hormone (GH) pulses frequency and an augmentation in its plasma concentrations as a result of starvation was found. The obtained results shows that the acute fasting exerts an inhibitory effect on the ovulation rate in ewes coincident with suppression in leptin, FSH and LH secretion and changes in signalization mediated by GH.
Seroprevalence of Ornithobacterium rhinotracheale Infection in Broiler and Broiler Breeder Chickens in West Azerbaijan Province, Iran
Authors: Allymehr M.
Published: January 2006

Ornithobacterium rhinotracheale is a pleomorphic Gram‐negative rod shaped bacterium of the rRNA superfamily V that is associated with respiratory disease in poultry. This study was conducted to determine the seroprevalence of O. rhinotracheale infection in broiler and broiler breeder chickens in West Azerbaijan (Urmia lake region) by using a commercial enzyme‐linked immunosorbent assay. In this study, 463 serum samples were obtained from 50 broiler flocks and 472 blood sera from 42 broiler breeder flocks. Results showed that 41 broiler flocks (82%) and 39 broiler breeder flocks (92.8%) were positive. Ornithobacterium rhinotracheale antibodies were detected in 205 (44.2%) of the 463 broiler serum samples. Of the 472 blood sera examined from broiler breeder, 340 (72%) were positive. The results of this study indicated that the prevalence of O. rhinotracheale antibodies is high in the broiler and broiler breeder flocks in West Azerbaijan.
Design of tomato fruits with reduced allergenicity by dsRNAi‐mediated inhibition of ns‐LTP (Lyc e 3) expression
Authors: Le Lien Quynh , Lorenz Yvonne , Scheurer Stephan , Fötisch Kay , Enrique Ernesto , Bartra Joan , Biemelt Sophia , Vieths Stefan , Sonnewald Uwe
Published: January 2006

Plant genetic engineering has the potential to introduce new allergenic proteins into foods but, at the same time, it can be used to remove established allergens. Here, we report the molecular characterization of Lyc e 3, a new tomato (Lycopersicon esculentum) allergen, and the efficient down‐regulation of its expression in transgenic tomato plants. Following the identification of an immunoglobulin E (IgE)‐binding 9‐kDa polypeptide in tomato peel, designated Lyc e 3, its partial amino acid sequence was determined by N‐terminal protein sequencing. Sequence comparison revealed that Lyc e 3 encodes a nonspecific lipid transfer protein (ns‐LTP). In plants, ns‐LTPs are encoded by large gene families which differ in primary amino acid sequence, expression and proposed cellular function. To identify Lyc e 3 encoding complementary DNAs (cDNAs), public tomato expressed sequence tag (EST) databases were screened for ns‐LTP sequences. Following this strategy, two cDNAs, LTPG1 and LTPG2, with high homology to the N‐terminal sequence of Lyc e 3, were identified. Ectopic expression of LTPG1 and LTPG2 in Escherichia coli, followed by immunoblotting, verified their IgE reactivity. Subsequently, transgenic tomato plants constitutively expressing LTPG1‐ or LTPG2‐specific double‐stranded RNA interference (dsRNAi) constructs were created and tested for the suppression of Lyc e 3 accumulation. Efficient silencing of Lyc e 3 was documented by Northern and Western blotting. In both cases, Lyc e 3 accumulation was decreased to levels below the detection limit (less than 0.5% of the wild‐type protein). The allergenic potential of Lyc e 3‐deficient tomato fruits was tested by measuring histamine release from sensitized human basophils stimulated with transgenic and parental lines. These assays revealed a strong (10‐ to 100‐fold) decrease in histamine release of human basophils challenged with transgenic fruit extracts when compared with control extracts. These results demonstrate the feasibility of creating low allergenic tomato fruits by means of dsRNAi inhibition.
Genetic transformation of barley (Hordeum vulgare L.) via infection of androgenetic pollen cultures with Agrobacterium tumefaciens
Authors: Kumlehn Jochen , Serazetdinova Liliya , Hensel Goetz , Becker Dirk , Loerz Horst
Published: January 2006

A novel genetic transformation method for barley (Hordeum vulgare L.), based on infection of androgenetic pollen cultures with Agrobacterium tumefaciens, is presented. Winter‐type barley cv. ‘Igri’ was amenable to stable integration of transgenes mediated by A. tumefaciens strain LBA4404 harbouring a vector system that confers hypervirulence, or by the non‐hypervirulent strain GV3101 with a standard binary vector. The efficacy of gene transfer was substantially influenced by pollen pre‐culture time, choice of Agrobacterium strain and vector system, Agrobacterium population density, medium pH and the concentrations of acetosyringone, CaCl2 and glutamine. After co‐culture, rapid removal of viable agrobacteria was crucial for subsequent development of the pollen culture. To this end, the growth of agrobacteria was suppressed by the concerted effects of appropriate antibiotics, low pH, reduced level of glutamine and high concentrations of CaCl2 and acetosyringone. Following infection with LBA4404 and GV3101, about 31% and 69%, respectively, of the primary transgenic (T0) plants carried a single copy of the sequence integrated. The use of hypervirulent A. tumefaciens and hygromycin resistance as a selectable marker resulted in 3.7 T0 plants per donor spike. About 60% of the primary transgenic plants set seed, indicating spontaneous genome doubling. An analysis of 20 T1 populations revealed that four progenies did not segregate for reporter gene expression. This indicates that the approach pursued enables the generation of instantly homozygous primary transgenic plants. The method established will be a valuable tool in functional genomics as well as for the biotechnological improvement of barley.
HETEROGENEITY IN A CURRENCY UNION WITH SOCIAL MARKET OBJECTIVES
Authors: Hallett Andrew Hughes , Weymark Diana N.
Published: January 2006

In this paper, we explore whether heterogeneity among union members could threaten the stability of the European Monetary Union. The types of heterogeneity we consider are (1) asymmetries in the transmission of monetary and fiscal policies, and (2) differences in national preferences for price stability, output growth, and income redistribution. Our results show that the costs of membership can be significant for countries whose transmissions, structure, or preferences deviate from those underlying the common monetary policy. In part, these costs arise because monetary policy imposed by an independent central bank automatically constrains the use of fiscal policy by national governments.
MONETARY–FISCAL INTERACTIONS WITH A CONSERVATIVE CENTRAL BANK
Authors: Lambertini Luisa
Published: January 2006

We study macroeconomic stabilization when monetary and fiscal policies interact via their effects on output and inflation and the monetary authority is more conservative than the fiscal. We find that monetary–fiscal interactions result in poor macroeconomic stabilization. With both policies discretionary, the Nash equilibrium is suboptimal with higher output and lower inflation than optimal; the Nash equilibrium may be extreme with output higher and inflation lower than either authority want. Leadership equilibria are not second best. Monetary commitment is completely negated by fiscal discretion and yields the same outcome as discretionary monetary leadership for all realizations of shocks. But fiscal commitment is not similarly negated by monetary discretion. Optimal macroeconomic stabilization requires either commitment of both monetary and fiscal policies, or identical targets for both authorities – output socially optimal and inflation appropriately conservative – or complete separation of tasks.
Healing effect of ketanserin on chronic leg ulcers in patients with diabetes
Authors: Quatresooz P , Kharfi M , Paquet P , Vroome V , Cauwenbergh G , Piérard GE
Published: January 2006

Background  The treatment of chronic leg ulcers remains a stubborn problem in many patients. Topical 2% ketanserin ointment, a 5HT2‐serotoninergic blocking agent, has been reported to improve healing of decubitus, venous, diabetic and ischaemic ulcers.

Method  The present double‐blind intra‐individual comparative study was performed in 12 women with diabetes presenting with at least two similar leg ulcers. In each subject, the two lesions were randomly assigned to be treated for 8 weeks by 2% ketanserin ointment or its unmedicated vehicle. Objective assessments of the dynamics of wound healing were performed using computerized morphometry. Evaluations were performed at 2‐week intervals for 8 weeks.

Results  A significant decrease in relative wound area was observed on the ketanserin‐treated ulcers compared with the placebo group.

Conclusion  Topical ketanserin is a valuable therapy for difficult‐to‐treat leg ulcers.
Limited regulation of somatodendritic dopamine release by voltage‐sensitive Ca2+channels contrasted with strong regulation of axonal dopamine release
Authors: Chen Billy T. , Moran Kimberly A. , Avshalumov Marat V. , Rice Margaret E.
Published: January 2006

The mechanism underlying somatodendritic release of dopamine (DA) appears to differ from that of axon‐terminal release. Specifically, somatodendritic DA release in the substantia nigra pars compacta (SNc) persists in low extracellular Ca2+concentrations that are insufficient to support axonal release in striatum, suggesting that limited Ca2+entry is necessary to trigger somatodendritic release. Here, we compared the role of voltage‐dependent Ca2+channels in mediating DA release in striatum versus SNc using specific blockers of N‐, P/Q‐, T‐, R‐ and L‐type Ca2+channels individually and in combination. Release of DA evoked by a single stimulus pulse in the dorsal striatum and SNc of guinea‐pig brain slices was monitored in real time using carbon‐fiber microelectrodes with fast‐scan cyclic voltammetry. Single‐pulse evoked DA release was shown to be independent of regulation by concurrently released glutamate or GABA acting at ionotropic receptors in both regions. Under these conditions, striatal DA release was completely prevented by an N‐type channel blocker, ω‐conotoxin GVIA (100 nm), and was decreased by 75% by the P/Q‐type channel blocker ω‐agatoxin IVA (200 nm). Blockade of T‐type channels with Ni2+(100 µm) or R‐type channels with SNX‐482 (100 nm) decreased axonal release in striatum by 25%, whereas inhibition of L‐type channels with nifedipine (20 µm) had no effect. By contrast, none of these Ca2+‐channel blockers altered the amplitude of somatodendritic DA release in the SNc. Even a cocktail of all blockers tested did not alter release‐signal amplitude in the SNc, although the duration of the release response was curtailed. The limited involvement of voltage‐dependent Ca2+channels in somatodendritic DA release provides further evidence that minimal Ca2+entry is required to trigger the release process, compared with that required for axon‐terminal release.
Neprilysin participates in skeletal muscle regeneration and is accumulated in abnormal muscle fibres of inclusion body myositis
Authors: Broccolini Aldobrando , Gidaro Teresa , Morosetti Roberta , Gliubizzi Carla , Servidei Tiziana , Pescatori Mario , Tonali Pietro A. , Ricci Enzo , Mirabella Massimiliano
Published: January 2006

Neprilysin (NEP, EP24.11), a metallopeptidase originally shown to modulate signalling events by degrading small regulatory peptides, is also an amyloid‐β‐ (Aβ) degrading enzyme. We investigated a possible role of NEP in inclusion body myositis (IBM) and other acquired and hereditary muscle disorders and found that in all myopathies NEP expression was directly associated with the degree of muscle fibre regeneration. In IBM muscle, NEP protein was also strongly accumulated in Aβ‐bearing abnormal fibres. In vitro, during the experimental differentiation of myoblasts, NEP protein expression was regulated at the post‐transcriptional level with a rapid increase in the early stage of myoblast differentiation followed by a gradual reduction thereafter, coincident with the progression of the myogenic programme. Treatment of differentiating muscle cells with the NEP inhibitor dl‐3‐mercapto‐2‐benzylpropanoylglycine resulted in impaired differentiation that was mainly associated with an abnormal regulation of Akt activation. Therefore, NEP may play an important role during muscle cell differentiation, possibly through the regulation, either directly or indirectly, of the insulin‐like growth factor I‐driven myogenic programme. In IBM muscle increased NEP may be instrumental in (i) reducing the Aβ accumulation in vulnerable fibres and (ii) promoting a repair/regenerative attempt of muscle fibres possibly through the modulation of insulin‐like growth factor I‐dependent pathways.
Selective deficits in the expression of striatal‐enriched mRNAs in Huntington's disease
Authors: Desplats Paula A. , Kass Kristi E. , Gilmartin Tim , Stanwood Gregg D. , Woodward Elliott L. , Head Steven R. , Sutcliffe J. Gregor , Thomas Elizabeth A.
Published: January 2006

We have identified and cataloged 54 genes that exhibit predominant expression in the striatum. Our hypothesis is that such mRNA molecules are likely to encode proteins that are preferentially associated with particular physiological processes intrinsic to striatal neurons, and therefore might contribute to the regional specificity of neurodegeneration observed in striatal disorders such as Huntington's disease (HD). Expression of these genes was measured simultaneously in the striatum of HD R6/1 transgenic mice using Affymetrix oligonucleotide arrays. We found a decrease in expression of 81% of striatum‐enriched genes in HD transgenic mice. Changes in expression of genes associated with G‐protein signaling and calcium homeostasis were highlighted. The most striking decrement was observed for a newly identified subunit of the sodium channel, beta 4, with dramatic decreases in expression beginning at 8 weeks of age. A subset of striatal genes was tested by real‐time PCR in caudate samples from human HD patients. Similar alterations in expression were observed in human HD and the R6/1 model for the striatal genes tested. Expression of 15 of the striatum‐enriched genes was measured in 6‐hydroxydopamine‐lesioned rats to determine their dependence on dopamine innervation. No changes in expression were observed for any of these genes. These findings demonstrate that mutant huntingtin protein causes selective deficits in the expression of mRNAs responsible for striatum‐specific physiology and these may contribute to the regional specificity of degeneration observed in HD.
The 5‐HT1A receptor agonist 8‐OH‐DPAT prevents prefrontocortical glutamate and serotonin release in response to blockade of cortical NMDA receptors
Authors: Calcagno E. , Carli M. , Invernizzi R. W.
Published: January 2006

We studied the role of 5‐HT1A receptors in controlling the release of glutamate (GLU) in the medial prefrontal cortex (mPFC) of conscious rats with the in vivo microdialysis technique. The effect of the 5‐HT1A receptor agonist 8‐hydroxy‐2‐(di‐n‐propylamino)tetralin infused in the prefrontal cortex was examined under basal conditions and on the rise of extracellular GLU (+106%) induced by co‐infusion of the competitive N‐methyl‐d‐aspartate receptor antagonist 3‐[(R)‐2‐carboxypiperazin‐4yl]‐propyl‐1‐phosphonic acid (CPP). 8‐OH‐DPAT (0.3 and 3 μm) had no effect on basal extracellular GLU, but the higher concentration completely abolished the rise of extracellular GLU induced by CPP. CPP also increased extracellular serotonin (5‐HT) in the mPFC (+50%) and this effect was antagonized by 3 μm 8‐OH‐DPAT which, by itself, had no effect on basal 5‐HT release. The effects of 8‐OH‐DPAT on extracellular GLU and 5‐HT were reversed by the 5‐HT1A receptor antagonist WAY100 635 (100 μm), indicating a selective involvement of 5‐HT1A receptors. WAY100 635 had no effect by itself. These results show that the stimulation of cortical 5‐HT1A receptors prevents the CPP‐evoked rise of extracellular GLU and 5‐HT and suggest that these effects may contribute to the ability of intracortical 8‐OH‐DPAT to counteract cognitive deficits caused by the blockade of NMDA receptors.
Mouse tryptophan hydroxylase isoform 2 and the role of proline 447 in enzyme function
Authors: Sakowski Stacey A. , Geddes Timothy J. , Kuhn Donald M.
Published: January 2006

Tryptophan hydroxylase (TPH) is the rate‐limiting enzyme in the synthesis of the neurotransmitter serotonin (5‐HT). Once thought to be a single gene product, TPH is now known to exist in two isoforms. Isoform 1 (TPH1) is found in the pineal gland and gut, and isoform 2 (TPH2) is selectively expressed in brain. A single‐nucleotide polymorphism in TPH2 results in a proline‐to‐arginine mutation at residue 447 and substantially lowers catalytic activity. In view of the importance of TPH in determining brain 5‐HT function, we cloned TPH2 and produced the P447R mutant to assess the importance of this proline in enzyme function. Catalytically active TPH2 and the P447R mutant were expressed at the predicted subunit molecular mass of 56 kDa. The P447R mutant expressed less than 50% of the activity of TPH2. Mutation of this conserved proline in TPH1 (P403R) also resulted in an enzyme with significantly lower activity than the wild‐type enzyme. The P447R mutant had a Vmax 50% lower than that of TPH2. The P447R mutation did not alter the oligomeric assembly of the protein, nor change its responsiveness to cysteine modification. The P447R mutation did not alter enzyme substrate specificity or stability, but conferred slightly enhanced sensitivity to inhibition by dopamine and diminished sensitivity to iron in catalysis. The conserved proline in TPH (residue 447 in TPH2 and 403 in TPH1) plays an important role in enzyme function by regulating Vmax of the catalytic reaction.
Resting and arecoline‐stimulated brain metabolism and signaling involving arachidonic acid are altered in the cyclooxygenase‐2 knockout mouse
Authors: Basselin Mireille , Villacreses Nelly E. , Langenbach Robert , Ma Kaizong , Bell Jane M. , Rapoport Stanley I.
Published: January 2006

Studies were performed to determine if cyclooxygenase (COX)‐2 regulates muscarinic receptor‐initiated signaling involving brain phospholipase A2(PLA2) activation and arachidonic acid (AA; 20 : 4n‐6) release. AA incorporation coefficients, k* (brain [1–14C]AA radioactivity/integrated plasma radioactivity), representing this signaling, were measured following the intravenous injection of [1–14C]AA using quantitative autoradiography, in each of 81 brain regions in unanesthetized COX‐2 knockout (COX‐2–/–) and wild‐type (COX‐2+/+) mice. Mice were administered arecoline (30 mg/kg i.p.), a non‐specific muscarinic receptor agonist, or saline i.p. (baseline control). At baseline, COX‐2–/–compared with COX‐2+/+mice had widespread and significant elevations of k*. Arecoline increased k* significantly in COX‐2+/+mice compared with saline controls in 72 of 81 brain regions, but had no significant effect on k* in any region in COX‐2–/–mice. These findings, when related to net incorporation rates of AA from brain into plasma, demonstrate enhanced baseline brain metabolic loss of AA in COX‐2–/–compared with COX‐2+/+mice, and an absence of a normal k* response to muscarinic receptor activation. This response likely reflects selective COX‐2‐mediated conversion of PLA2‐released AA to prostanoids.
Calpain is activated in degenerating photoreceptors in the rd1 mouse
Authors: Paquet‐Durand Francois , Azadi Seifollah , Hauck Stefanie M. , Ueffing Marius , van Veen Theo , Ekström Per
Published: January 2006

The retinal degeneration (rd)1 mouse displays an inherited retinal degeneration and therefore allows studies of the molecular mechanisms behind the blinding disease retinitis pigmentosa. Activation of the calcium‐dependent protease calpain has been suggested to play an important role in cell death in various tissues, but little is known about the expression and activity of calpain during inherited retinal degeneration. Using microarray techniques, transcript levels of cyclic AMP response element‐binding protein (CREB)‐1, calpastatin and of various calpain genes were analysed in the rd1 mouse compared with its wild‐type control. Expression of distinct calpain isoforms and calpastatin was investigated using immunofluorescence and immunoblotting. Gene transcription and protein expression levels were compared with calpain activity using an enzymatic assay that allowed monitoring of calpain activity at the cellular level. We found that CREB‐1 and calpastatin expression was reduced in rd1 retinas, whereas calpain activity was substantially increased in rd1 photoreceptors. Calpain activity peaked at postnatal day 13, together with rd1 photoreceptor cell death. Calpain‐specific inhibitors decreased calpain activity in situ. These results indicate that activation of calpains correlates with rd1 photoreceptor cell death, which raises the possibility of using calpain inhibitors to prevent or delay photoreceptor degeneration.
Glia re‐sealed particles freshly prepared from adult rat brain are competent for exocytotic release of glutamate
Authors: Stigliani Sara , Zappettini Simona , Raiteri Luca , Passalacqua Mario , Melloni Edon , Venturi Consuelo , Tacchetti Carlo , Diaspro Alberto , Usai Cesare , Bonanno Giambattista
Published: January 2006

Glial subcellular re‐sealed particles (referred to as gliosomes here) were purified from rat cerebral cortex and investigated for their ability to release glutamate. Confocal microscopy showed that the glia‐specific proteins glial fibrillary acidic protein (GFAP) and S‐100, but not the neuronal proteins 95‐kDa postsynaptic density protein (PSD‐95), microtubule‐associated protein 2 (MAP‐2) and β‐tubulin III, were enriched in purified gliosomes. Furthermore, gliosomes exhibited labelling neither for integrin‐αM nor for myelin basic protein, which are specific for microglia and oligodendrocytes respectively. The Ca2+ ionophore ionomycin (0.1–5 µm) efficiently stimulated the release of tritium from gliosomes pre‐labelled with [3H]d‐aspartate and of endogenous glutamate in a Ca2+‐dependent and bafilomycin A1‐sensitive manner, suggesting the involvement of an exocytotic process. Accordingly, ionomycin was found to induce a Ca2+‐dependent increase in the vesicular fusion rate, when exocytosis was monitored with acridine orange. ATP stimulated [3H]d‐aspartate release in a concentration‐ (0.1–3 mm) and Ca2+‐dependent manner. The gliosomal fraction contained proteins of the exocytotic machinery [syntaxin‐1, vesicular‐associated membrane protein type 2 (VAMP‐2), 23‐kDa synaptosome‐associated protein (SNAP‐23) and 25‐kDa synaptosome‐associated protein (SNAP‐25)] co‐existing with GFAP immunoreactivity. Moreover, GFAP or VAMP‐2 co‐expressed with the vesicular glutamate transporter type 1. Consistent with ultrastructural analysis, several ∼30‐nm non‐clustered vesicles were present in the gliosome cytoplasm. It is concluded that gliosomes purified from adult brain contain glutamate‐accumulating vesicles and can release the amino acid by a process resembling neuronal exocytosis.
Identification of Shark Species Composition and Proportion in the Hong Kong Shark Fin Market Based on Molecular Genetics and Trade Records
Authors: CLARKE SHELLEY C. , MAGNUSSEN JENNIFER E. , ABERCROMBIE DEBRA L. , MCALLISTER MURDOCH K. , SHIVJI MAHMOOD S.
Published: January 2006

Abstract:  The burgeoning and largely unregulated trade in shark fins represents one of the most serious threats to shark populations worldwide. In Hong Kong, the world's largest shark fin market, fins are classified by traders into Chinese‐name categories on the basis of market value, but the relationship between market category and shark species is unclear, preventing identification of species that are the most heavily traded. To delineate these relationships, we designed a sampling strategy for collecting statistically sufficient numbers of fins from traders and categories under conditions of limited market access because of heightened trader sensitivities. Based on information from traders and morphological inspection, we hypothesized matches between market names and shark taxa for fins within 11 common trade categories. These hypotheses were tested using DNA‐based species identification techniques to determine the concordance between market category and species. Only 14 species made up approximately 40% of the auctioned fin weight. The proportion of samples confirming the hypothesized match, or concordance, varied from 0.64 to 1 across the market categories. We incorporated the concordance information and available market auction records for these categories into stochastic models to estimate the contribution of each taxon by weight to the fin trade. Auctioned fin weight was dominated by the blue shark (Prionace glauca), which was 17% of the overall market. Other taxa, including the shortfin mako (Isurus oxyrinchus), silky (Carcharhinus falciformis), sandbar (C. obscurus), bull (C. leucas), hammerhead (Sphyrna spp.), and thresher (Alopias spp.), were at least 2–6% of the trade. Our approach to marketplace monitoring of wildlife products is particularly applicable to situations in which quantitative data at the source of resource extraction are sparse and large‐scale genetic testing is limited by budgetary or other market access constraints.
A 16‐Year Study of Forest Disturbance and Understory Bird Community Structure and Composition in Tanzania
Authors: NEWMARK WILLIAM D.
Published: January 2006

Abstract:  I compared understory bird community structure and composition among primary, slightly disturbed, and moderately disturbed forest in the East Usambara Mountains in Tanzania. Comparisons were conducted at two spatiotemporal scales: short term, conducted in 1999 and 2000, in which treatments (disturbance levels) were replicated, and long term, conducted from 1989–2004 along the same disturbance gradient of a subset of the short‐term sites. I used capture‐recapture models to assess the probability of detection and estimate species richness and population growth rates. The probability of detection of species did not vary significantly among disturbance levels but did vary significantly among species. Over the short‐ and long‐term surveys, estimated species richness did not vary significantly among disturbance levels. Temporal variability in estimated species richness and the relative abundance of guilds did vary significantly among disturbance levels yet was contingent on survey length. The coefficient of variation in species richness over the short‐term survey was <5% across all disturbance levels, whereas over the long‐term survey it was 35% in slightly disturbed forest, 11% in moderately disturbed forest, and 0% in primary forest. In the short‐term survey, zero of seven feeding guilds varied significantly in relative abundance among disturbance levels, whereas over the long‐term survey four of seven (57%) feeding guilds did so. Terrestrial insectivores were most adversely affected by forest disturbance. Population growth rates (λ) between 1989 and 2004 for the more common species of terrestrial insectivores did not vary significantly among disturbance levels and for these species were significantly ≤1.00, indicating the recovery time for terrestrial insectivores in slightly and moderately disturbed forest is very long. These results illustrate the importance of long‐term studies in assessing ecological impacts of forest disturbance and the importance of protecting primary forest in the Eastern Arc Mountains.
Inbreeding and Endangered Species Management: Is New Zealand Out of Step with the Rest of the World?
Authors: JAMIESON IAN G. , WALLIS GRAHAM P. , BRISKIE JAMES V.
Published: January 2006

Abstract:  There is growing evidence that inbreeding can negatively affect small, isolated populations. This contrasts with the perception in New Zealand, where it has been claimed that native birds are less affected by inbreeding depression than threatened species from continental regions. It has been argued that New Zealand's terrestrial birds have had a long history of small population size with frequent inbreeding and that this has “purged” deleterious alleles. The rapid recovery of many tiny and inbred populations after introduced predators have been controlled, and without input from more genetically diverse populations, has further supported the view that inbreeding is not a problem. This has led to a general neglect of inbreeding as a factor in recovery programs for highly endangered species such as the Black Robin (Petroica traversi) and Kakapo (Strigops habroptilis). We examined the reasons for this situation and review the New Zealand evidence for genetic purging. Complete purging of the genetic load and elimination of inbreeding depression are unlikely to occur in natural populations, although partial purging may be more likely where small populations have become inbred over an extended period of time, such as on small isolated islands. Recent molecular data are consistent with the view that island endemics, including New Zealand's threatened birds, have low genetic variation and hence have possibly gone through longer periods of inbreeding than threatened species from continental regions. Nevertheless, results from recent field studies in New Zealand indicate that, despite the opportunity for purging, inbreeding depression is evident in many threatened species. Although inbreeding depression has not prevented some populations from recovering from severe bottlenecks, the long‐term consequences of inbreeding and small population size—the loss of genetic variation—are potentially much more insidious. The degrees to which genetic factors reduce population viability generally remain unquantified in New Zealand. Although minimizing ecological risks (e.g., preventing reinvasion of islands by mammalian predators) will continue to receive high priority in New Zealand because of their much larger impacts, we advocate that genetic considerations be better integrated into recovery plans.
Effectiveness of a Regional Corridor in Connecting Two Florida Black Bear Populations
Authors: DIXON JEREMY D. , OLI MADAN K. , WOOTEN MICHAEL C. , EASON THOMAS H. , McCOWN J. WALTER , PAETKAU DAVID
Published: January 2006

Abstract: Corridors may mitigate the adverse effects of habitat fragmentation by restoring or maintaining connectivity between disjunct populations. The efficacy of corridors for large carnivores, however, has rarely been evaluated objectively. We used noninvasive sampling, microsatellite analysis, and population assignment tests to evaluate the effectiveness of a regional corridor in connecting two Florida black bear (Ursus americanus floridanus) populations (Osceola and Ocala). Bear movement was predominantly unidirectional, with a limited mixing of individuals from the two populations in one area of the corridor. We also documented bears in Osceola that were genetically assigned to Ocala and bears in Osceola that may be offspring from an Osceola‐Ocala mating. Our results indicate that the Osceola‐Ocala corridor is functional and provides a conduit for gene flow between these populations. Human development, however, may hinder the use of the Osceola‐Ocala corridor by bears. The noninvasive sampling and genetic methods we used provide a means of evaluating corridor effectiveness that can help identify linkages necessary for maintaining metapopulation structure and population viability.
Species Imperilment and Spatial Patterns of Development in the United States
Authors: BROWN ROGER M. , LABAND DAVID N.
Published: January 2006

Abstract: Conservation biologists and others hypothesize that humankind's “ecological footprint” is affected not only by the sheer intensity of human activity but also by its spatial arrangement. We used a multivariate statistical model and state‐level data to evaluate correlations between species imperilment and the level and spatial distribution of human settlement and infrastructure development in the United States. The level of human activity—measured by the number of people and households, incidence of roads, and intensity of nighttime lights—was significantly correlated with the ecological imperilment of species. Our regression models consistently showed that a 1% increase in the level of human activity across the United States was associated with about a 0.25% increase in the proportion of plant and animal species considered at risk of extinction by The Nature Conservancy. The distribution of human activity did not affect species imperilment. Our results point to rising levels of human activity—and not some particular (e.g., sprawling) distribution of human activity—as the most relevant anthropogenic factor explaining biodiversity loss in the United States.
Differences in the Umbrella Effects of African Amphibians and Mammals Based on Two Estimators of the Area of Occupancy
Authors: RONDININI CARLO , BOITANI LUIGI
Published: January 2006

Abstract: Conservation organizations are collecting large‐scale data regarding distribution and threats to vertebrate taxa. These data sets will enable planners to systematically identify large‐scale conservation priorities; however, they will cover only a tiny proportion of living organisms. Therefore, it is essential to investigate to what extent the areas selected for conservation actions can provide protection for other species. We analyzed the umbrella effect between amphibians and mammals across mainland Africa. We built habitat suitability models within the geographic ranges of 1654 species, based on data collected in the framework of the World Conservation Union (IUCN) Global Amphibian Assessment and IUCN Global Mammal Assessment. We applied systematic reserve selection algorithms to two sets of estimators of the area of occupancy of amphibians and mammals (geographic ranges and estimated suitable areas) and thus selected four reserve systems. We then quantified the protection that each of the four systems provided for amphibians and mammals. Reserves selected for amphibians and mammals were comparable in area, with the former concentrated in the Afrotropical region and the latter more evenly dispersed. Mammal reserves left fewer gaps in species coverage among amphibians than the reverse, but amphibian reserves included a larger proportion of each mammal's area of occupancy than the reverse. For both taxa, setting reserves to include estimated suitable areas instead of ranges resulted in the clustering of reserves in the tropics. Furthermore, it efficiently protected hidden gaps (species with unsuitable portions of their range inside protected areas) in the other taxon and included a higher proportion of the area of occupancy of the other taxon. Overall, amphibians and mammals in Africa acted as an umbrella for a high proportion of species in the other taxon. Focusing on estimated suitable areas instead of ranges improved the umbrella effect of both taxa.
Cost‐Efficiency of Decaying Wood as a Surrogate for Overall Species Richness in Boreal Forests
Authors: JUUTINEN ARTTI , MÖNKKÖNEN MIKKO , SIPPOLA ANNA‐LIISA
Published: January 2006

Abstract: Decaying wood is one of the most important elements for species richness in boreal forests. We tested how well reserve selection based on the amount and quality of decaying wood results in a representation of four ecologically different taxa (beetles, birds, wood‐inhabiting fungi, and vascular plants). We also compared the cost‐efficiency of the use of dead‐wood indicators with comprehensive species inventory. Our database included 32 seminatural old‐forest stands located in northern Finland. Decaying wood was a relatively good indicator of saproxylic species but not overall species richness. Even though dead wood did not reflect accurately overall species richness, our results indicated that the use of decaying wood as an indicator in site selection was more cost‐efficient than using information from large‐scale species inventories. Thus, decaying wood is a valuable surrogate for species richness, but other cost‐efficient indicators that reflect the requirements of those species which are not dependent on decaying wood should be identified.
Controls on low‐pressure anatexis
Authors: GERBI C. C. , JOHNSON S. E. , KOONS P. O.
Published: January 2006

Low‐pressure anatexis, whereby rocks melt in place after passing through the andalusite stability field, develops under more restricted conditions than does low‐pressure metamorphism. Our thermal modelling and review of published work indicate that the following mechanisms, operating alone, may induce anatexis in typical pelitic rocks without inducing wholesale melting in the lower crust: (i) magmatic advection by pervasive flow; (ii) crustal‐scale detachment faulting; and (iii) the presence of a high heat‐producing layer. Of these, only magmatic advection by pervasive flow and crustal‐scale detachment faulting have been shown quantitatively to provide sufficient heat to cause widespread melting. Combinations of the above mechanisms with pluton‐scale magmatic advection, shear heating, removal of the lithospheric mantle, or with each other provide additional means of developing suitable high temperatures at shallow crustal levels to generate low‐pressure anatexis.
Comparison of the Role of the Subcutaneous Tissues in Cutaneous Wound Healing in the Dog and Cat
Authors: BOHLING MARK W. , HENDERSON RALPH A. , SWAIM STEVEN F. , KINCAID STEVEN A. , WRIGHT JAMES C.
Published: January 2006

Objective—To describe and compare the contribution of the subcutaneous tissues to 1st and 2nd intention cutaneous wound healing in the dog and cat.

Study Design—Experimental study.

Animals—Domestic shorthaired cats (n=6) and 6 beagle dogs.

Methods—Paired wounds were created on either side of the dorsal midline; the subcutaneous tissue was removed on 1 side and left intact on the other. Square, open wounds of the dorsal aspect of the thorax were observed for 21 days to monitor granulation tissue formation, wound contraction, epithelialization, and total healing (contraction+epithelialization). Breaking strength of sutured linear wounds was measured 7 days after wounding. Laser‐Doppler perfusion imaging (LDPI) was used to measure cutaneous perfusion.

Results—First intention healing: subcutaneous tissue removal had no consistent effect on sutured wound strength at 7 days in dogs or cats. Second intention healing: removal of subcutaneous tissue reduced wound perfusion, granulation, contraction, epithelialization, and total healing. Granulation tissue formation and wound contraction were delayed to a significantly greater degree in cats than in dogs (P<.05). Two dogs (33%) had minor wound infections.

Conclusions—The subcutaneous tissues make an important contribution to 2nd intention cutaneous healing. Dog and cat wounds had delayed 2nd intention healing when subcutaneous tissues were removed; wounds in dogs, but not cats, had largely recovered from this delay by 21 days.

Clinical Relevance—Extensive debridement of subcutaneous tissue may delay wound healing particularly in feline patients. A higher risk for wound infections may accompany extensive removal of subcutaneous tissues in dogs.
Buried Tension Sutures: Force‐Tension Comparisons of Pulley, Double Butterfly, Mattress, and Simple Interrupted Suture Patterns
Authors: AUSTIN BRENDA R. , HENDERSON RALPH A.
Published: January 2006

Objectives—To compare suture patterns (simple interrupted, modified pulley, horizontal mattress, double butterfly) by use of a novel in vitro model that quantifies force required for closure against tension.

Study Design—In vitro study.

Sample Population—Suture constructs.

Methods—An in vitro suturing frame was constructed with extension springs to provide a standard resistance against movement of 2 panels of loops toward each other. Four different suture patterns were applied to the frame in randomized trials. The frame was affixed to a tensiometer that measured the force required for each suture pattern to close a fixed distance (3.81 cm) at a constant rate (5.08 cm/min) against the tension (0.6 kg/cm) of the extension springs. The closure distance and tension were selected subjectively to mimic tension encountered clinically during wound reconstruction oncologic surgical procedures.

Results—The modified pulley suture required the least force to close, followed by the double butterfly, simple interrupted, and horizontal mattress patterns.

Conclusions—The modified pulley suture and double butterfly suture patterns require less force to close a given distance under tension than either simple interrupted or horizontal mattress suture patterns.

Clinical Relevance—Application of tension relieving suture techniques for fascia, subcutaneous, and buried‐knot subdermal suturing should be considered to facilitate direct closure of wounds under tension. Modified pulley and double butterfly suture patterns offer some mechanical advantage by requiring less force to achieve closure compared with other suture patterns that might be used in reconstructive surgery.