bluuebunny/crossref_metadata_2025 huggingface dataset:
Soluble ICAM‐1 and VCAM‐1 as Markers of Endothelial Activation
Authors: Videm V. , Albrigtsen M.
Published: March 2008

Activated endothelium releases the soluble adhesion molecules vascular cell adhesion molecule‐1 (sVCAM‐1) and intercellular adhesion molecule‐1 (sICAM‐1). Measurement of fluid‐phase adhesion molecules is therefore used to quantify endothelial activation, but it is unclear which is the better marker. The aims of the study were to compare the relationships between mRNA, surface and total expression and released VCAM‐1 and ICAM‐1 in endothelial cell cultures during activation, and to compare human umbilical vein endothelial cells (HUVEC) with the microvascular cell line HMEC‐1. sVCAM‐1 better represented mRNA and surface expression changes in HUVEC undergoing endotoxin stimulation than did sICAM‐1. Very little VCAM‐1 was released from endotoxin‐stimulated HMEC‐1, and sICAM‐1 seemed a better activation marker for these cells. During incubation of HUVEC in media with glucose concentrations of 5.6, 10.6 or 20.6 mm, VCAM‐1 was released to the media in a dose‐dependent way without changes in surface expression. ICAM‐1 was not influenced by the glucose concentration. There are situations when VCAM‐1 concentrations in the media do not mirror the surface expression on HUVEC in culture, indicating that measurements of soluble adhesion molecules may not necessarily be representative of the conditions on the cell surface. Endothelium from different locations showed varying responses with respect to VCAM‐1 and ICAM‐1 liberation upon endotoxin stimulation. Thus, both sVCAM‐1 and sICAM‐1 should be quantified in clinical studies of endothelial activation until their characteristics are better clarified.
Source model for the Mw 6.1, 31 March 2006, Chalan‐Chulan Earthquake (Iran) from InSAR
Authors: Peyret M. , Rolandone F. , Dominguez S. , Djamour Y. , Meyer B.
Published: March 2008

We use InSAR to measure deformation and kinematics of the Mw = 4.9 Borujerd (2005/05/03) and Mw = 6.1 Chalan‐Chulan (2006/03/31) earthquakes that occurred in the Zagros fold‐and‐thrust belt. The focal mechanism of the 2006 event is consistent with right lateral strike‐slip motion and the event ruptured the Dorud‐Borujerd segment of the Main Recent Fault. An Envisat interferogram spanning the 2006 event shows peak ground deformation of 9 cm in the satellite line‐of‐sight along a 10 km long fault portion. The interferogram spanning the 2005 earthquake is rather related to atmospheric artefact than to ground deformation. Dislocation models of the 2006 Chalan‐Chulan event indicate dextral slip amounting to a maximum of 90 cm at a depth of 4 km. The predicted vertical displacements are in good agreement with differential levelling data. The 2006 event filled only a small part of the seismic gap located between large M = 7 events that occurred in 1909 and 1957.
High rate GPS data on active volcanoes: an application to the 2005–2006 Mt. Augustine (Alaska, USA) eruption
Authors: Mattia Mario , Palano Mimmo , Aloisi Marco , Bruno Valentina , Bock Yehuda
Published: March 2008

Volcanic eruptions are usually preceded by measurable signals of growing unrest, the most evident of which are the increase in seismicity and ground deformation. It is also important to identify precursors of a possible renewal of the volcanic activity and to distinguish between an eruptive activity characterized by an intrusion (with the related destructive power) and a migration of magma stored in the main conduits. The 2005–2006 eruption at Mt. Augustine (Alaska, USA) is a good example of a massive migration of magmatic fluids from depth (about 1 km b.s.l.) under the effect of gas overpressure. The movements, recorded by High Rate GPS (HRGPS) data (15 s of sampling and processing rate) from the stations deployed on the volcano, define the dimensions and the characteristics of the shallow plumbing system. In this study, we propose a model of the different stages preceding the effusive phase (the ‘precursory phase’), where gas overpressure in the body of the volcano opens the terminal conduit.
Variations of b‐values at the western edge of the Ryukyu Subduction Zone, north‐east Taiwan
Authors: Lin Jing‐Yi , Sibuet Jean‐Claude , Hsu Shu‐Kun
Published: March 2008

Using earthquakes relocated in north‐east Taiwan, we estimated b‐value distribution along a cross‐section located near the Ryukyu slab edge, and four b‐value anomalous areas are evidenced: (1) a high b‐value body lying on top of a low Vp, low Vs and high Vp/Vs sausage‐like body was considered as a region of enhanced partial melt or water supply above which seismicity occurs; (2) beneath the Ilan Plain, an anomalous area characterized by b‐values slightly higher than 1.1 might give evidence to the magma conduits to the Kueishantao Island; (3) above the Ryukyu Wadati‐Benioff zone, at depths ranging from 90 to 110 km, a high b‐value anomaly might correspond to the depth where dehydration occurs in the subducting oceanic plate; and (4) a low b‐value area located within the Ryukyu slab, at depths ranging from 70 to 90 km, might be linked to the compressive mechanisms shown by focal mechanisms and the bending of the subducting plate.
Was Cathaysia part of Proterozoic Laurentia? – new data from Hainan Island, south China
Authors: Li Zheng‐Xiang , Li Xian‐Hua , Li Wu‐Xian , Ding Shijiang
Published: March 2008

We report here new field and analytical data from Precambrian rocks on Hainan Island of the Cathaysia Block, south China, and examine its probable connection to Laurentia. Granitoids and newly discovered felsic volcanic rocks dated at 1433 ± 6 Ma and 1439 ± 9 Ma (SHRIMP U‐Pb zircon) on Hainan Island are coeval with, and isotopically similar to the 1500–1350 Ma trans‐continental granite‐rhyolite province in southern Laurentia. Quartzites unconformably overlying the ca. 1430 Ma volcaniclastic rocks on Hainan Island are interpreted as locally‐sourced Grenvillian foreland basin deposits that can be correlated with the Deer Trail Group of south‐western Laurentia. The detrital provenance of the quartzites contains age populations comparable to the 1610–1490 Ma, westerly‐sourced non‐Laurentian detrital grains reported in the Belt Basin of south‐western Laurentia. Our new data thus make Cathaysia the most likely continental block next to western Laurentia before and during the late Mesoproterozoic assembly of Rodinia.
Cuticular hydrocarbons are heritable in the cricket Teleogryllus oceanicus
Authors: THOMAS M. L. , SIMMONS L. W.
Published: March 2008

The ability of individuals to respond differentially to conspecifics depending on their genetic relatedness is a widespread phenomenon across the animal kingdom. Despite this, little is known about the selection processes that act on the phenotypic variation of traits used during recognition. Here we use a quantitative genetic approach to examine the patterns of genetic variation in cuticular hydrocarbon (CHC) profiles, a pheromonal system used extensively in insect communication. Using gas chromatography, we found family specificity in the CHC profiles of male crickets, Teleogryllus oceanicus. Across CHC peaks, our mean coefficient of additive genetic variation was 10.8%. Multivariate principal component analysis showed that most axes of variation were weighted by CHC peaks with significant additive genetic variation. Our results provide evidence that variation in CHC profiles can reflect genetic relatedness, supporting the widely held belief that this phenotypic trait is used as a mechanism for chemosensory kin recognition.
Costs, benefits and the evolution of inducible defences: a case study with Daphnia pulex
Authors: HAMMILL E. , ROGERS A. , BECKERMAN A. P.
Published: March 2008

Phenotypic plasticity is one major source of variation in natural populations. Inducible defences, which can be considered threshold traits, are a form of plasticity that generates ecological and evolutionary consequences. A simple cost–benefit model underpins the maintenance and evolution of these threshold, inducible traits. In this model, a rank‐order switch in expected fitness, defined by costs and benefits of induction between defended and undefended morphs, predicts the risk level at which individuals should induce defences. Here, taking predator‐induced morphological defences in Daphnia pulex as a threshold trait, we provide the first comprehensive investigation into the costs and benefits of a threshold trait, and how they combine to reflect fitness and predict the switchpoint at which induction should occur. We develop reaction norms that show genetic variation in switchpoints. Further experiments show that induction can confer a survival benefit and a cost in terms of lifetime reproductive success. Together, these two traits combine to estimate expected fitness and can predict the switchpoint between an undefended and a defended strategy. The predictions match the reaction norm data for clones that experience these costs and benefits, and correspond well to independent field data on induction. However, predictions do not, and cannot, match for clones that do not gain a benefit from induction. This study confirms that a simple theory, based on life history costs and benefits, is a sufficient framework for understanding the ecology and evolution of inducible, threshold traits.
The More the Scarier: Adult Richardson’s Ground Squirrels (Spermophilus richardsonii) Assess Response Urgency Via the Number of Alarm Signallers
Authors: Sloan Jennifer L. , Hare James F.
Published: March 2008

Richardson’s ground squirrels (RGS) produce alarm calls that warn conspecifics of potential predators. We presented free‐living adult and juvenile RGS with playbacks of repetitive alarm calls from one vs. two juvenile callers broadcast sequentially through two spatially separated loudspeakers. Adult RGS spent a greater proportion of time vigilant in response to two vs. one calling squirrel, whereas juvenile RGS did not respond differentially to two vs. one caller. Apparently then, the relative inexperience of juvenile RGS with alarm calls and the context in which such calls are emitted precludes their enumeration of alarm callers. Taken together with our earlier finding that adult but not juvenile RGS ignore information regarding response urgency encoded in the rate of juvenile produced repetitive calls, our present results suggest a developmental shift in response‐urgency perception. Adult RGS selectively extract information regarding response urgency via discrimination of the number of callers, ignoring less reliable information encoded in the rate of repetitive calls issued by inexperienced juvenile signallers.
Juvenile Female Aggression in Cooperatively Breeding Pied Babblers: Causes and Contexts
Authors: Raihani Nichola J. , Ridley Amanda R. , Browning Lucy E. , Nelson‐Flower Martha J. , Knowles Sarah
Published: March 2008

Sex biases in adult aggression have been well studied and commonly arise when resources which affect survival or lifetime reproductive success are less abundant or more valuable for individuals of one sex. Despite the prevalence of sex biases in adult aggression, evidence for sex biases in juvenile aggression is scant. Here, we present evidence for female‐biased juvenile aggression in cooperatively breeding pied babblers (Turdoides bicolor). Unlike most cases of non‐lethal sibling aggression, juvenile aggression in pied babblers does not seem to be determined by food availability. Instead, we found that juvenile aggression was related to adult dispersal patterns. This study shows that females that were more aggressive as juveniles attempted dispersal earlier than less aggressive females. Potential explanations for the association between juvenile aggression and adult dispersal patterns are discussed.
Little Brown Bats (Myotis lucifugus) Recognize Individual Identity of Conspecifics Using Sonar Calls
Authors: Kazial Karry A. , Kenny Tammy L. , Burnett Stephen C.
Published: March 2008

Bats use sonar calls to locate prey and orient in their environment but they may also be used by conspecifics to obtain information about a caller. Statistical analysis of sonar calls provides evidence that variation carries social information about a caller, including individual identity. We hypothesized that little brown bats (Myotis lucifugus) would be able to recognize individuals given the potential fitness benefits of doing so. We performed playback trials using a habituation‐discrimination design to determine whether little brown bats are able to recognize the individual identity of a caller based on variation in their sonar calls. Each subject bat was played the calls of bat A until they habituated (defined as a 50% decrease from the beginning call rate), then the calls of bat B or a new call sequence of bat A (a control, referred to as bat A’) were played. Each subject received a unique pair of playback recordings (bat A and B) from adult female bats from the same colony (but a different colony from the subject) and the order of trials was randomized. The response measures were habituation time (s) and call rate (calls/s). Within a trial, subjects habituated to calls of bat A and transferred this habituation to the bat A’ sequence. In addition, they increased their call rates when played calls of bat B. Comparing between trials, subjects increased their call rate to the calls of bat B to a greater relative extent than to the calls of bat A’. These results provide the first evidence that bats recognize individual identity of conspecifics (as opposed to discrimination of groups), which has implications for the social interactions of bats.
Himalayan wild cherry (Prunus cerasoides D. Don): a new host of Apple chlorotic leaf spot virus
Authors: Rana T. , Chandel V. , Hallan V. , Zaidi A. A.
Published: March 2008

Himalayan wild cherry (Prunus cerasoides), widely distributed in the Himalayas, was found to exhibit mild virus‐like symptoms. Leaf samples from affected plants were subjected to enzyme‐linked immunosorbent assay indexing for known pome and stone fruit viruses, viz., Apple mosaic virus, Apple chlorotic leaf spot virus (ACLSV), Prunus necrotic ring spot virus and Apple stem grooving virus. Results showed the presence of ACLSV. For further characterization, the coat protein gene was amplified by reverse transcription‐polymerase chain reaction (RT‐PCR). Sequencing of the amplicon confirmed the presence of ACLSV. The isolate shared 98% amino acid sequence identity with P1R9D9 (Bulgarian) and C‐2 (Hungarian) isolates of ACLSV. This study reports the presence of ACLSV in Himalayan wild cherry.
Pseudomonas syringae pv. aesculi associated with horse chestnut bleeding canker in Germany
Authors: Schmidt O. , Dujesiefken D. , Stobbe H. , Moreth U. , Kehr R. , Schröder Th.
Published: March 2008

Bacteria were isolated from necrotic lesions on a horse chestnut tree (Aesculus hippocastanum) with bleeding canker in Hamburg, Germany. Sequencing of the rDNA‐ITS region revealed great similarity to pathovars of Pseudomonas syringae. Pseudomonas syringae pv. aesculi was identified by sequence homology of the gyrase B gene. This is the first report of P. syringae pv. aesculi in Germany. Phytophthora was not detected.
Effects of Exogenous Insulin on Luteolysis and Reproductive Cyclicity in the Mare
Authors: Rambags BPB , Van Rossem AW , Blok EE , De Graaf‐Roelfsema E , Kindahl H , Van Der Kolk JH , Stout TAE
Published: March 2008

Contents

Insulin is a pancreatic hormone that classically regulates carbohydrate and fat metabolism, but also appears to play a role in various reproductive processes. A preliminary study suggested insulin production by day 10 to 18 equine conceptuses. The aim of the present study was to examine the hypothesis that insulin is the conceptus signal responsible for maternal recognition of pregnancy (MRP) in the mare, or otherwise influences reproductive cyclicity during the MRP period. Six Warmblood mares were treated daily during days 7 to 17 after ovulation of two successive oestrous cycles with either (short and intermediate acting) insulin or control saline. Mares were assigned randomly to treatment, and crossed over during the subsequent cycle. Time of ovulation and corpus luteum surface area were determined by serial transrectal ultrasonographic examination of the mares’ ovaries, and daily jugular vein blood samples were analysed for progesterone and luteinizing hormone (LH) concentrations. On day 14 of dioestrus, the luteolytic drive was examined by measuring systemic 15‐ketodihydroprostaglandin F2α(PG‐metabolite) release in response to oxytocin challenge. In addition, yolk sac fluid recovered from 32 day 10 to 14 equine conceptuses was analysed for insulin concentrations. Insulin administration did not affect luteal size, dioestrus length, the interovulatory interval, or circulating LH concentrations. Insulin administration also failed to suppress oxytocin‐induced PGF2αrelease, and tended to depress systemic progesterone concentrations. Finally, insulin could not be detected in the yolk sac fluid of day 10 to 14 equine conceptuses by radio‐immunoassay. It is concluded that insulin administered daily during days 7 to 17 of dioestrus has little or no effect on reproductive cyclicity in the mare, and is unlikely to be the MRP signal.
Review Article: Cytochrome P450 enzyme, and transport protein mediated herb–drug interactions in renal transplant patients: Grapefruit juice, St John's Wort – and beyond! (Review Article)
Authors: NOWACK RAINER
Published: March 2008

Aim:  To survey the evidence for plant‐products to modify cytochrome P450 enzyme, and transport protein mediated drug metabolism in renal transplant patients.

Methods:  A literature search was performed to identify “in vitro” and “in vivo” research on plant‐products that might cause overdosage or loss of efficacy of immunosuppressive drugs in transplant patients by the interaction mechanisms already characterized for grapefruit juice and St. John's Wort.

Results:  The interaction mechanisms of St. John's Wort by pregnane X‐receptor mediated upregulation of cytochrome‐P450 enzyme 3A4 and p‐glycoprotein expression and of grapefruit juice by mechanism‐based inhibition of intestinal CYP3A4 suggest that many other plant products will likewise cause interactions with drugs because they occupy the same metabolic pathways. The respective research on foods, spices and medicinal herbs is listed in a comprehensive table and weighted according to its strength of evidence to cause clinically relevant interactions.

Conclusion:  Physicians supervising drug‐regimes in renal transplant patients should be aware of plant products beyond SJW and GFJ to possibly cause overdosage or failure of drug‐treatments by herb‐drug interactions.
Livestock grazing: A matter of ecology
Authors: Dunbabin Tom
Published: March 2008

Summary  Agricultural ecology is the study of agricultural systems, their component parts (particularly the ecological components) and their internal and external interactions. This paper explores how we, as a family of graziers, employ ecological principles in agricultural land management, specifically livestock grazing, and illustrates this with some specific farm management practices. Implications are explored for natural resource management policy and practice that endeavours to engage land mangers adept at the practical application of ecological principles in managing their grazing businesses.
Woodlands on farms in southern New South Wales: A longer‐term assessment of vegetation changes after fencing
Authors: Spooner Peter G. , Briggs Sue V.
Published: March 2008

Summary  Fencing incentive programmes have been widely used throughout Australia to assist landholders to fence remnant woodland vegetation, to control grazing and improve native vegetation condition. This study investigated vegetation and soil condition in remnant woodlands fenced for 7–9 years in the Murray catchment area in southern New South Wales. Surveys were undertaken at 42 sites, where vegetation condition was assessed in paired fenced and unfenced sites. Semi‐structured interviews were also conducted with landholders to gather management information. Woodlands surveyed were Yellow Box/Blakely's Red Gum (Eucalyptus melliodora/E. blakelyi, 15 sites), Grey Box (E. microcarpa, 13 sites) and White Cypress Pine (Callitris glaucophylla, 14 sites).

Fencing resulted in a range of responses which were highly variable between sites and vegetation types. In general, fenced sites had greater tree regeneration, cover of native perennial grasses, less cover of exotic annual grasses and weeds, and less soil compaction than unfenced sites. However, there was greater tree recruitment in remnants to the west of the study area, and tree recruitment was positively correlated with time since fencing. Within sites, tree recruitment tended to occur in more open areas with a good cover of native perennial grasses, as compared to sites with a dense tree canopy, or dominated by exotic annuals grasses or weeds. Forty‐eight per cent of fenced sites had no tree regeneration. There was a significant decline in native perennial grasses, and increase of several unpalatable weeds in many fenced areas, suggesting certain ecological barriers may be preventing further recovery. However, drought conditions and associated grazing are the most likely cause of this trend. A range of grazing strategies was implemented in fenced sites which require further research as a conservation management tool. Continued long‐term monitoring is essential to detect key threats to endangered woodland remnants.
Assessing the biodiversity benefits of plantations: The Plantation Biodiversity Benefits Score
Authors: Cawsey E. Margaret , Freudenberger David
Published: March 2008

Summary  All forests, including commercial plantations, provide a range of habitats for conserving and enhancing elements of native biodiversity. However, the biodiversity values of commercial plantations will depend on the management practices adopted on site, as well as the landscape context of the plantation. The present study describes a generic, quantitative method for assessing the potential biodiversity benefits that might be derived from a plantation, depending on the management practices adopted. This method is based on existing ecological design and management principles. The Plantation Biodiversity Benefits Score (PBBS) was designed to be repeatable and practical to apply. The method can be used either as a stand‐alone tool or as part of an integrated framework to assess and compare the commercial and environmental benefits that can be derived from different layouts, management practices and locations of plantations anywhere in Australia.
Autologous serum in the management of recalcitrant dry eye syndrome
Authors: Lee Graham A , Chen Simon X
Published: March 2008

Abstract

Purpose:  To evaluate the efficacy and safety of long‐term application of autologous serum eye drops treating recalcitrant dry eye syndrome.

Methods:  A retrospective chart review was conducted of patients who had serum eye drops between May 2001 and March 2006. The clinical data collected included sex, age, indications for serum eye drops, frequency of lubricant eye drops use before and after serum eye drop treatment, Schirmer tear function test with anaesthesia, fluorescein staining at baseline and at follow up and changes in subjective symptoms.

Results:  There were 46 eyes of 23 patients (19 female and 4 male) in the study group. The average follow‐up period was 17.3 months (range 6–55 months). Corneal fluorescein staining of 34 eyes (73.9%) showed improvement at follow up. Sixteen patients (32 eyes, 69.6%) reported a decreased frequency of lubricant use including eight patients (16 eyes, 34.8%) who used only serum eye drops for dry eye treatment. Eighteen patients (35 eyes, 76.1%) reported subjective improvement after using serum eye drops. No significant complications were reported in this study.

Conclusion:  Serum eye drops can be effective in treating recalcitrant dry eye syndrome and should be available as a management option when other treatments have failed. Meticulous attention must be paid to the possible contamination of the bottle to minimize the risk of infection.
Cryopreserved amniotic membrane transplantation for the management of symptomatic bullous keratopathy
Authors: Georgiadis Nick S , Ziakas Nikolas G , Boboridis Kostas G , Terzidou Chrysa , Mikropoulos Dimitrios G
Published: March 2008

Abstract

Background:  To report the results of cryopreserved human amniotic membrane transplantation for the management of symptomatic bullous keratopathy.

Methods:  Prospective non‐comparative interventional case series study. Consecutive cases with symptomatic bullous keratopathy for more than 12 months not amenable to conservative treatment were managed with amniotic membrane transplantation. They were recruited over a 5‐year period (September 1999 to November 2004) in one referral centre. Only one eye of each patient (the worse affected eye in bilateral cases) was operated. A 360 degree conjunctival peritomy was followed by removal of the diseased corneal epithelium. Amniotic membrane was transplanted over the cornea as a patch and sutured to the free conjunctival edges. Primary outcome measures were ocular pain and epithelial defects; secondary measures were visual acuity and ocular surface inflammation.

Results:  Four out of 85 recruited cases did not complete the minimum observation of 12 months and were excluded from the study. The mean follow‐up period for the remaining 81 cases was 21 ± 4.2 months (range 14–34 months). Seventy‐one (87.6%) eyes became asymptomatic with healed epithelium, seven required repeated amniotic transplantation and three underwent penetrating keratoplasty. Visual acuity improved in 64 (79%) patients and remained unchanged in 14. No complications were recorded.

Conclusions:  Amniotic membrane transplantation is an efficient and safe treatment for symptomatic bullous kerato pathy, when penetrating keratoplasty is not available. It has been shown to alleviate pain, promote corneal epithelialization and reduce conjunctival inflammation whereas in some cases it may also improve visual acuity.
Biometric calculation of intraocular lens power for cataract surgery following pupil dilatation
Authors: Bansal Shveta , Quah Say A , Turpin Tim , Batterbury Mark
Published: March 2008

Abstract

Background:  The ability to perform biometry accurately on a dilated pupil can greatly facilitate the efficiency of a cataract service as it can be done on the day of surgery. The purpose of this study was to assess the repeatability of axial length (AL) calculations in undilated pupils and measure the difference in predicted and actual refractive outcomes in dilated pupils compared with undilated pupils.

Methods:  First, intraobserver repeatability was assessed by taking two consecutive recordings of AL using applanation A‐scan ultrasonography in undilated pupils in 21 eyes. The mean AL for each eye was compared with a measurement made following pupil dilatation. Second, we audited the mean spherical equivalent refractive errors following routine cataract surgery in 38 patients with undilated pupils and 36 patients with dilated pupils.

Results:  The mean difference in intraobserver measurements was −0.05 mm (standard deviation [SD] 0.15) with pupils undilated. Following pupil dilatation, the mean dilated AL differed from the mean undilated AL reading by only 0.03 mm (P > 0.05). The mean differences between planned and actual refractive error were 0.71D (SD 0.54) and 0.55D (SD 0.41) in dilated and undilated patients, respectively. This was not statistically significant (P > 0.05). The range of differences between target and actual refraction was −1.45D to 2.70D for undilated patients and −1.88D to 1.18D in dilated patients.

Conclusion:  Although there was a greater spread of postoperative refractive errors in the dilated group, there were no statistically or clinically significant differences in postoperative refractive errors between the two categories of patients. Our study shows that applanation biometry may be safely performed for the purpose of cataract surgery after pupil dilatation.
Long‐term results of viscocanalostomy in pseudoexfoliative and primary open angle glaucoma
Authors: Wishart Peter K , Wishart Manijeh S , Choudhary Anshoo , Grierson Ian
Published: March 2008

Abstract

Purpose:  To document the outcome of viscocanalostomy (VC) alone or combined with phacoemulsification (phaco‐VC) in eyes with pseudoexfoliation glaucoma (PEXG) and primary open angle glaucoma (POAG).

Methods:  A prospective, comparative study of 314 eyes undergoing VC in two centres over 6 years was conducted. Main outcome measures were: (i) intraocular pressure (IOP) control (complete success was IOP ≤ 18 mmHg without medication and failure IOP > 18 mmHg); and (ii) requirement for Nd:YAG laser goniopuncture (YAG‐GP) if IOP > 21 mmHg.

Results:  In the POAG group, 174 eyes underwent phaco‐VC and 104 VC. In the PEX group, 20 eyes underwent phaco‐VC and 16 VC. At final follow up, complete success rate (CSR) was 76% for POAG phaco‐VC, 67% for POAG VC, 95% for PEXG phaco‐VC and 63% for PEXG VC with mean IOP reduction of 29.9%, 40%, 42.5% and 51%, respectively. Without YAG‐GP, by 3 years postoperatively the failure rate was 100% for PEXG eyes and 21% for POAG eyes undergoing VC alone, but PEXG eyes undergoing phaco‐VC were 100% successful. CSR for YAG‐GP was 92% in PEXG VC eyes and 55% in POAG VC eyes.

Conclusions:  In phakic eyes with PEXG undergoing VC, an absolute requirement for long‐term success was YAG‐GP. This was not the case in POAG eyes or PEXG eyes undergoing phaco‐VC. Late IOP rise in phakic PEXG eyes and restoration of IOP control following YAG‐GP suggests that continued release of PEX material from the lens capsule with time blocks the outflow through the trabecular‐Descemetic window created by VC.
Sexually dimorphic activation of the periaqueductal gray–rostral ventromedial medullary circuit during the development of tolerance to morphine in the rat
Authors: Loyd Dayna R. , Morgan Michael M. , Murphy Anne Z.
Published: March 2008

The midbrain periaqueductal gray (PAG) and its descending projections to the rostral ventromedial medulla (RVM) provides an essential neural circuit for the antinociceptive effects of opiates, and has been implicated in the development of tolerance to morphine. Systemic morphine activates a greater proportion of PAG–RVM neurons in male vs female rats, and induces tolerance to a greater degree in males. The present studies tested the hypothesis that if the PAG–RVM pathway is essential for the development of tolerance, then: (i) morphine activation of the PAG–RVM pathway should decline as tolerance develops; and (ii) sex differences in the development of tolerance to morphine should be reflected as a greater decline in the activation of this pathway in males. These hypotheses were tested in male and female rats using behavioral testing (hot‐plate) and immunohistochemistry to map the activation of the PAG–RVM pathway following repeated morphine administration (5 mg/kg; s.c.). In males, morphine potency decreased from 3.0 to 6.3 mg/kg, indicating tolerance, and this was paralleled by a steady decline in the percentage of PAG–RVM output neurons activated by morphine. In contrast, in females the shift in morphine potency was significantly attenuated (D50 6–8.3 mg/kg), and no significant difference in the activity of PAG–RVM output neurons was noted. These results demonstrate that the greater development of tolerance to morphine administration in male rats corresponds with a significant reduction in the activation of the PAG–RVM circuit and suggest a central role for the PAG in the development of tolerance to morphine.
Early differential processing of verbs and nouns in the human brain as indexed by event‐related brain potentials
Authors: Hasting Anna S. , Winkler István , Kotz Sonja A.
Published: March 2008

A recent study on syntactic influences on the mismatch negativity (MMN) reported preliminary evidence that processing or representational differences between verbs and nouns could be reflected in modulations of this early component of the event‐related brain potential (ERP). However, this previous investigation was unable to separate the putative word category effects from possible influences of the direction of acoustic change on the MMN response. The present study disentangled these two effects by comparing the effects of the direction of acoustic change within and isolated from the lexical context that had previously been used to create the word‐category contrast. Although the direction of acoustic change exerted a significant influence on the MMN amplitude, some of the temporal and topographic characteristics of the MMN and the overall pattern of the deviance‐related ERP response proved to be specific to word‐category effects. These findings provide the first reliable evidence that the MMN can serve as an index of word‐category‐specific processing and support the notion of early processing and representational differences between verbs and nouns.
Exogenous agmatine has neuroprotective effects against restraint‐induced structural changes in the rat brain
Authors: Zhu Meng‐Yang , Wang Wei‐Ping , Cai Zheng‐Wei , Regunathan Soundar , Ordway Gregory
Published: March 2008

Agmatine is an endogenous amine derived from decarboxylation of arginine catalysed by arginine decarboxylase. Agmatine is considered a novel neuromodulator and possesses neuroprotective properties in the central nervous system. The present study examined whether agmatine has neuroprotective effects against repeated restraint stress‐induced morphological changes in rat medial prefrontal cortex and hippocampus. Sprague‐Dawley rats were subjected to 6 h of restraint stress daily for 21 days. Immunohistochemical staining with β‐tubulin III showed that repeated restraint stress caused marked morphological alterations in the medial prefrontal cortex and hippocampus. Stress‐induced alterations were prevented by simultaneous treatment with agmatine (50 mg/kg/day, i.p.). Interestingly, endogenous agmatine levels, as measured by high‐performance liquid chromatography, in the prefrontal cortex and hippocampus as well as in the striatum and hypothalamus of repeated restraint rats were significantly reduced as compared with the controls. Reduced endogenous agmatine levels in repeated restraint animals were accompanied by a significant increase of arginine decarboxylase protein levels in the same regions. Moreover, administration of exogenous agmatine to restrained rats abolished increases of arginine decarboxylase protein levels. Taken together, these results demonstrate that exogenously administered agmatine has neuroprotective effects against repeated restraint‐induced structural changes in the medial prefrontal cortex and hippocampus. These findings indicate that stress‐induced reductions in endogenous agmatine levels in the rat brain may play a permissive role in neuronal pathology induced by repeated restraint stress.
Kv4 (A‐type) potassium currents in the mouse medial nucleus of the trapezoid body
Authors: Johnston Jamie , Griffin Sarah J. , Baker Claire , Forsythe Ian D.
Published: March 2008

Principal neurones of the mouse medial nucleus of the trapezoid body (MNTB) possess multiple voltage‐gated potassium currents, including a transient outward current (or A‐current), which is characterized here. The A‐current exhibited rapid voltage‐dependent inactivation and was half inactivated at resting membrane potentials. Following a hyperpolarizing pre‐pulse to remove inactivation, the peak transient current was 1.07 nA at −17 mV. The pharmacological characteristics of this A‐current were consistent with Kv4 subunits in expression studies; the A‐current was resistant to block by tetraethylammonium and dendrotoxin‐I but sensitive to millimolar concentrations of 4‐aminopyridine and 5 µm hanatoxin. Immunohistochemistry confirmed that Kv4.3 sub‐units are present in the MNTB. In a single‐compartment model of an MNTB neurone, the A‐current served to accelerate the decay of the initial action potentials in a stimulus train and suggested that removal of A‐current steady‐state inactivation could raise firing threshold for non‐calyceal synaptic inputs. This A‐type current was not observed in the rat.
α‐Phenyl‐n‐tert‐butyl‐nitrone ameliorates hippocampal injury and improves learning and memory in juvenile rats following neonatal exposure to lipopolysaccharide
Authors: Fan Lir‐Wan , Tien Lu‐Tai , Mitchell Helen J. , Rhodes Philip G. , Cai Zhengwei
Published: March 2008

Neonatal exposure to infectious agents may result in long‐term neurological disability, and is particularly associated with the subsequent development of motor and cognitive disturbances. Our previous studies have shown that treatment with α‐phenyl‐n‐tert‐butyl‐nitrone (PBN) following exposure to lipopolysaccharide (LPS) reduces LPS‐induced brain injury in the neonatal rat. To examine whether PBN has long‐lasting protective effects and ameliorates LPS‐induced motor and cognitive dysfunction, PBN (100 mg/kg) was administered intraperitoneally 5 min after an LPS (1 mg/kg) intracerebral injection in postnatal day 5 (P5) Sprague–Dawley rat pups. Neurobehavioral tests were carried out from P3 to P21, and brain injury was examined at 24 h and 16 days after LPS injection. Neonatal LPS exposure resulted in hyperactivity from P13 to P17 in the open field task as compared with the control rat. Neurobehavioral deficits that were still observable at P21 included dysfunction in the beam‐walking and pole tests, learning and memory deficits in the passive avoidance task, and less anxiety‐like response in the elevated plus‐maze task. These behavioral findings were matched by LPS‐induced axonal injury in the CA1 region of the middle dorsal hippocampus (HP), reduction in the size of the HP and the number of neurons in the CA1 region of the middle dorsal HP, and loss of tyrosine hydroxylase immunoreactivity in neurons in the substantia nigra and ventral tegmental areas. Treatment with PBN provided long‐lasting protection against the LPS‐induced axonal injury and neuronal loss, and improved the associated neurological dysfunctions in juvenile rats.
The effects of running and of inhibiting adult neurogenesis on learning and memory in rats
Authors: Wojtowicz J. Martin , Askew Michele L. , Winocur Gordon
Published: March 2008

The presence of ongoing adult neurogenesis within the highly plastic hippocampal circuitry poses questions as to the relevance of new neurons to learning and memory. Correlational and causal evidence suggests that some, but not all, hippocampal tasks involve the new neurons. The evidence with regard to spatial learning in the water maze, one of the most commonly used hippocampal tasks, is contradictory. In this study we examined the effects of irradiation‐induced reduction in neurogenesis on spatial learning and another standard hippocampal task, contextual fear conditioning, in rats that experienced normal cage conditions or voluntary running. The results indicate that reduced neurogenesis had little effect on spatial learning but severely impaired contextual fear conditioning. It was suggested that compensatory mechanisms within the hippocampus may have contributed selectively to sparing of spatial function. Performance on the fear conditioning task was weakly related to enhanced neurogenesis or running. The results improve our understanding of the functional role of adult neurogenesis in behaving animals.
High dose dexmedetomidine as the sole sedative for pediatric MRI
Authors: MASON KEIRA P. , ZURAKOWSKI DAVID , ZGLESZEWSKI STEVEN E. , ROBSON CAROLINE D. , CARRIER MAUREEN , HICKEY PAUL R. , DINARDO JAMES A.
Published: March 2008

Objective:  This large‐scale retrospective review evaluates the sedation profile of dexmedetomidine.

Aim:  To determine the hemodynamic responses, efficacy and adverse events associated with the use of high dose dexmedetomidine as the sole sedative for magnetic resonance imaging (MRI) studies.

Background:  Dexmedetomidine has been used at our institution since 2005 to provide sedation for pediatric radiological imaging studies. Over time, an effective protocol utilizing high dose dexmedetomidine as the sole sedative agent has evolved.

Methods/Materials:  As part of the ongoing Quality Assurance process, data on all sedations are reviewed monthly and protocols modified as needed. Data were analyzed from all 747 consecutive patients who received dexmedetomidine for MRI sedation from April 2005 to April 2007.

Results:  Since 2005, the 10‐min loading dose of our dexmedetomidine protocol increased from 2 to 3 μg·kg−1, and the infusion rate increased from 1 to 1.5 to 2 μg·kg−1·h−1. The current sedation protocol progressively increased the rate of successful sedation (able to complete the imaging study) when using dexmedetomidine alone from 91.8% to 97.6% (P = 0.009), reducing the requirement for adjuvant pentobarbital in the event of sedation failure with dexmedetomidine alone and decreased the mean recovery time by 10 min (P < 0.001). Although dexmedetomidine sedation was associated with a 16% incidence of bradycardia, all concomitant mean arterial blood pressures were within 20% of age‐adjusted normal range and oxygen saturations were 95% or higher.

Conclusion:  Dexmedetomidine in high doses provides adequate sedation for pediatric MRI studies. While use of high dose dexmedetomidine is associated with decreases in heart rate and blood pressure outside the established ‘awake’ norms, this deviation is generally within 20% of norms, and is not associated with adverse sequelae. Dexmedetomidine is useful as the sole sedative for pediatric MRI.
Lidocaine 5% patch for localized chronic neuropathic pain in adolescents: report of five cases
Authors: NAYAK SANDEEP , CUNLIFFE MARY
Published: March 2008

We describe a case series of five adolescents who were managed with lidocaine 5% patches for chronic localized neuropathic pain from a variety of causes with minimal adverse effects. Treatment was effective in four of five patients with only one patient complaining of minimal pain relief. 5% Lidocaine patches have been used for treatment of chronic neuropathic pain in adults and we have found this to be effective in management of localized neuropathic pain in children and adolescents.
Temporal and spatial archaeal colonization of hydrothermal vent deposits
Authors: Pagé Antoine , Tivey Margaret K. , Stakes Debra S. , Reysenbach Anna‐Louise
Published: March 2008

Thermocouple arrays were deployed on two deep‐sea hydrothermal vents at Guaymas Basin (27°0.5′N, 111°24.5′W) in order to measure in situ temperatures at which microorganisms colonize the associated mineral deposits. Intact sections of three structures that formed around the arrays were collected after 4 and 72 day deployments (named BM4, BM72 and TS72). Archaeal diversity associated with discreet subsamples collected across each deposit was determined by polymerase chain reaction amplification of 16S rRNA genes. Spatial differences in archaeal diversity were observed in all deposits and appeared related to in situ temperature. In BM4, no 16S rRNA genes were detected beyond about 1.5 cm within the sample (> 200°C). Phylotypes detected on the outside of this deposit belong to taxonomic groups containing mesophiles and (hyper)thermophiles, whereas only putative hyperthermophiles were detected 1.5 cm inside the structure (∼110°C). In contrast, the more moderate thermal gradient recorded across TS72 was associated with a deeper colonization (2–3 cm inside the deposit) of putative hyperthermophilic phylotypes. Although our study does not provide a precise assessment of the highest temperature for the existence of microbial habitats inside the deposits, archaeal 16S rRNA genes were detected directly next to thermocouples that measured 110°C (Methanocaldococcus spp. in BM4) and 116°C (Desulfurococcaceae in TS72). The successive array deployments conducted at the Broken Mushroom (BM) site also revealed compositional differences in archaeal communities associated with immature (BM4) and mature chimneys (BM72) formed by the same fluids. These differences suggest a temporal transition in the primary carbon sources used by the archaeal communities, with potential CO2/H2 methanogens prevalent in BM4 being replaced by possible methylotroph or acetoclastic methanogens and heterotrophs in BM72. This study is the first direct assessment of in situ conditions experienced by microorganisms inhabiting actively forming hydrothermal deposits at different stages of structure development.
Presence of vancomycin and ampicillin‐resistant Enterococcus faecium of epidemic clonal complex‐17 in wastewaters from the south coast of England
Authors: Caplin Jonathan L. , Hanlon Geoffrey W. , Taylor Huw D.
Published: March 2008

The occurrence and diversity of vancomycin‐resistant enterococci (VRE) in wastewaters from the Brighton and Hove area of south‐east England were investigated. VRE were recovered from 71% of raw urban wastewater samples, 22% of treated urban wastewater samples, 15% of hospital wastewater sample and 33% of farm wastewater samples. Two hundred and eighty‐eight isolates were typed and identified and the minimum inhibitory concentrations (MICs) to six antibiotics were determined for selected VRE. Vancomycin‐resistant Enterococcus faecium (VREF) strains with a vancomycin MIC of more than 32 μg ml−1 were examined by polymerase chain reaction for the vanA, vanB and esp genes. Twenty‐three VREF with the vanA or vanB gene were further analysed by multilocus sequence typing which revealed that a cluster of VREF from both hospital and urban wastewaters belonged to the high‐risk, epidemic, clonal complex‐17 (CC17). Vancomycin‐resistant Enterococcus faecium belonging to the CC17 group contained the purK‐1 allele, were resistant to ampicillin and frequently ciprofloxacin, and usually contained the esp gene. To the authors' knowledge, this is the first report of CC17 strains isolated from urban wastewaters in the UK, and indicates that certain clones carrying antibiotic resistance or virulence traits indicative of the hospital environment can be detected in the urban wastewater system.
Linkages between bacterioplankton community composition, heterotrophic carbon cycling and environmental conditions in a highly dynamic coastal ecosystem
Authors: Teira Eva , Gasol Josep M. , Aranguren‐Gassis María , Fernández Ana , González Jose , Lekunberri Itziar , Álvarez‐Salgado X. Antón
Published: March 2008

We used mesocosm experiments to study the bacterioplankton community in a highly dynamic coastal ecosystem during four contrasting periods of the seasonal cycle: winter mixing, spring phytoplankton bloom, summer stratification and autumn upwelling. A correlation approach was used in order to measure the degree of coupling between the dynamics of major bacterial groups, heterotrophic carbon cycling and environmental factors. We used catalysed reporter deposition‐fluorescencein situhybridization to follow changes in the relative abundance of the most abundant groups of bacteria (Alphaproteobacteria, Gammaproteobacteria and Bacteroidetes). Bacterial carbon flux‐related variables included bacterial standing stock, bacterial production and microbial respiration. The environmental factors included both, biotic variables such as chlorophyll‐a concentration, primary production, phytoplankton extracellular release, and abiotic variables such as the concentration of dissolved inorganic and organic nutrients. Rapid shifts in the dominant bacterial groups occurred associated to environmental changes and bacterial bulk functions. An alternation between Alphaproteobacteria and Bacteroidetes was observed associated to different phytoplankton growth phases. The dominance of the group Bacteroidetes was related to high bacterial biomass and production. We found a significant, non‐spurious, linkage between the relative abundances of major bacterial groups and bacterial carbon cycling. Our results suggest that bacteria belonging to these major groups could actually share a function in planktonic ecosystems.