bluuebunny/crossref_metadata_2025_split huggingface dataset:
Australian Defence Force surgical support to peacekeeping operations in East Timor
Authors: Chambers Anthony J. , Crozier John A. 
Published: July 2004

Background:  The Australian Defence Force (ADF) has provided surgical support to peacekeeping operations in East Timor since September 1999. The aim of the present paper is to document the wide range of surgical procedures performed by the ADF in East Timor from September 1999 to December 2002 on peacekeeping force personnel and the civilian population.Methods:  Records of all surgical procedures performed by the ADF in East Timor from their arrival in September 1999 to December 2002 were retrospectively reviewed. Details of the type of procedures performed and anaesthetic administered, the age and sex of the patients and whether they were a member of peacekeeping forces or East Timorese civilian were recorded.Results:  There were 702 surgical procedures performed by the ADF in East Timor during this period, of which 401 (57%) were for peacekeeping force personnel and 301 (43%) were for East Timorese or other civilians. The most commonly performed procedures were for the management of non‐battle wounds, accounting for 181 cases (26%). Battle‐type wounds accounted for only 36 procedures (5%). Obstetric and gynaecology cases accounted for 30 procedures (4%). Fifty‐six procedures (8%) were on children 12 years or younger.Conclusions:  The wide range of surgical procedures performed by the ADF during peacekeeping operations in East Timor highlights the requirement for deployed surgeons to possess a broad range of clinical skills and has implications for their preparation and training. Battle‐type wounds accounted for only a small proportion of procedures.
Splenic preservation: an additional haemostatic measure during mesh splenorrhaphy
Authors: Reddy Chaitan G. , Chalasani Venu , Pathma‐Nathan Nimalan 
Published: July 2004

Background:  Various treatment measures have been described in achieving splenic preservation following splenic injury. We describe an additional measure in achieving haemostasis during mesh splenorrhaphy.Methods:  Oxycel (BD, Franklin Lakes, NJ, USA) (topical haemostatic agent composed of oxidized cellulose) is sutured onto the inside of Dexon (Sherwood, Davis & Geck, St Louis, MO, USA) (polyglycolic acid) mesh.Results:  Two patients with splenic lacerations were operated on from July 2002 to February 2003 using this technique and both patients did not experience postoperative abdominal complications and were clinically well at follow up 1−2 months later.Conclusions:  In our experience this technique made the Dexon mesh bulkier and easier to secure as well as more haemostatic.
Elective surgery for dIverticular disease: an audit of surgical pathology and treatment
Authors: Killingback Mark , Barron Prudence E. , Dent Owen F. 
Published: July 2004

Background:  There is a need for a better classification of the surgical pathology of diverticular disease treated by elective resection.Methods:  A prospective audit was conducted over a 25‐year period, during which the surgeon studied the surgical pathology. The results of surgical treatment have been related to the pathology.Results:  Two hundred and six patients were managed by elective resection with a postoperative mortality of 1.0% and a total morbidity of 51.5%. The surgical pathology was classified as: non‐inflammatory 25 (12.6%), localized diverticulitis 90 (43.7%) and extracolic diverticulitis 90 (44.2%).Conclusions:  This classification is useful to relate the technical requirements of surgery and the outcome to the surgical pathology. Postoperative morbidity is associated with the presence and severity of inflammatory pathology and therefore the casemix of any series will have a significant impact on this aspect.
Shear mode fatigue crack growth in 1050 aluminium
Authors: MAKABE C. , SOCIE D. F. , SUEYOSHI T. 
Published: July 2004

ABSTRACTThe shear mode crack growth mechanism in 1050 aluminium was investigated using pre‐cracked specimens. A small blind hole was drilled in the centre section of the specimens in order to predetermine the crack initiation position, and a push–pull fatigue test was used to make a pre‐crack. Crack propagation tests were carried out using both push–pull and cyclic torsion with a static axial load. With push–pull testing, the main crack grew by a mixed mode. It is thus apparent that shear deformation affects the fatigue crack growth in pure aluminium. In tests using cyclic torsion, the fatigue crack grew by a shear mode. The micro‐cracks initiated perpendicular and parallel to the main crack's growth direction during the cyclic torsion tests. However, the growth direction of the main crack was not changed by the coalescence of the main crack and the micro‐cracks. Shear mode crack growth tends to occur in aluminium. The crack growth behaviour is related to a material's slip systems. The number of slip planes in aluminium is smaller than that of steel and the friction stress during edge dislocation motion of aluminium is lower than many other materials. Correlation between the crack propagation rate and the stress intensity factor range was almost the same in both push–pull and cyclic torsion with tension in this study.
Comparison of retardation behaviour of 2024‐T3 and 7075‐T6 Al alloys
Authors: CELIK C. E. , VARDAR O. , KALENDEROGLU V. 
Published: July 2004

ABSTRACTRetardation in fatigue crack growth rate following the application of single and periodic tensile overloads was studied for 2024‐T3 and 7075‐T6 aluminium alloys. Tests were performed at constant stress and at constant stress intensity factor ranges, at a load ratio of R= 0.1, at a baseline ΔK in the 10–20 MPa√m range which corresponds to the Paris regime. Overload ratios of 1.3–1.65 were studied with overload spacing, n, varying from 20 to 10 000 cycles. 2024‐T3 displayed an order of magnitude higher retardation, Nd, due to single tensile overloads compared to 7075‐T6. Periodic overloads induced maximum retardation when n/Nd≈ 0.5 for both alloys, the magnitude being only 15% higher for 2024‐T3.
Segregation of two endocannabinoid‐hydrolyzing enzymes into pre‐ and postsynaptic compartments in the rat hippocampus, cerebellum and amygdala
Authors: Gulyas A. I. , Cravatt B. F. , Bracey M. H. , Dinh T. P. , Piomelli D. , Boscia F. , Freund T. F. 
Published: July 2004

AbstractFatty acid amide hydrolase (FAAH) and monoglyceride lipase (MGL) catalyse the hydrolysis of the endocannabinoids anandamide and 2‐arachidonoyl glycerol. We investigated their ultrastructural distribution in brain areas where the localization and effects of cannabinoid receptor activation are known. In the hippocampus, FAAH was present in somata and dendrites of principal cells, but not in interneurons. It was located mostly on the membrane surface of intracellular organelles known to store Ca2+ (e.g. mitochondria, smooth endoplasmic reticulum), less frequently on the somatic or dendritic plasma membrane. MGL immunoreactivity was found in axon terminals of granule cells, CA3 pyramidal cells and some interneurons. In the cerebellum, Purkinje cells and their dendrites are intensively immunoreactive for FAAH, together with a sparse axon plexus at the border of the Purkinje cell/granule cell layers. Immunostaining for MGL was complementary, the axons in the molecular layer were intensively labelled leaving the Purkinje cell dendrites blank. FAAH distribution in the amygdala was similar to that of the CB1 cannabinoid receptor: evident signal in neuronal somata and proximal dendrites in the basolateral nucleus, and hardly any labelling in the central nucleus. MGL staining was restricted to axons in the neuropil, with similar relative signal intensities seen for FAAH in different nuclei. Thus, FAAH is primarily a postsynaptic enzyme, whereas MGL is presynaptic. FAAH is associated with membranes of cytoplasmic organelles. The differential compartmentalization of the two enzymes suggests that anandamide and 2‐AG signalling may subserve functional roles that are spatially segregated at least at the stage of metabolism.
Dopaminergic nigrostriatal projections regulate neural precursor proliferation in the adult mouse subventricular zone
Authors: Baker Sarah A. , Baker K. Adam , Hagg Theo 
Published: July 2004

AbstractAn understanding of the regulators of neurogenesis in the normal and diseased brain is necessary in order to recruit endogenously produced neural precursors for cell replacement in neurodegenerative disorders such as Parkinson's disease. The location of dopaminergic projections from the midbrain to the neostriatum and nucleus accumbens overlaps with the most active region of neurogenesis in the adult brain, the subventricular zone of the anterior lateral ventricle. This suggests that dopamine may contribute to regulation of the subventricular niche of adult neurogenesis. Here, we show in adult mice that destruction of the dopaminergic neurons in the substantia nigra and ventral tegmental area in a 6‐hydroxydopamine model of Parkinson's disease reduced the number of proliferating neural precursors in the subventricular zone of the anterior lateral ventricle by ∼ 40%. The effect on neural precursor proliferation correlated with the extent of dopaminergic denervation in the neighboring neostriatum. This identifies dopamine as one of the few known endogenous regulators of adult neurogenesis with implications for the potential use of endogenous neural precursors in cell replacement strategies for Parkinson's disease.
CREBαδ– deficient mice show inhibition and low activity in novel environments without changes in stress reactivity
Authors: Hebda‐Bauer Elaine K. , Watson Stanley J. , Akil Huda 
Published: July 2004

AbstractThe ability to respond to unexpected or novel stimuli is critical for survival. Determining that a stimulus is indeed novel requires memory to ascertain its lack of familiarity. As the long‐term synaptic changes involved in memory formation require the cAMP response element binding protein (CREB), we examined the extent to which CREB is involved in responses to novel environments. These environments typically trigger an endocrine stress response. Thus, we measured behavioural and stress hormone responses to three novel and one familiar environment in mice with a targeted disruption of the alpha and delta isoforms of the CREB gene (CREBαδ– deficient mice). We found CREBαδ– deficient mice to be less active and more inhibited in the elevated plus maze, open field, and light/dark box, without showing differences in anxiety‐like behaviour. This inhibition is unique to novel environments because these mice display a normal phenotype in the home cage, a familiar environment. Although CREBαδ– deficient mice exhibit altered behaviour in novel environments, they show normal reactivity to mild and moderate stress as both basal and stress levels of corticosterone are similar to those of wild‐type controls. This is the first report of CREBαδ– deficient mice to: (i) show altered behaviour, not related to learning and memory‐associated behaviours, upon initial exposure to environments and (ii) serve as an animal model that can dissociate locomotor activity from anxiety‐like behaviour in novel environments.
Strain differences affect the induction of status epilepticus and seizure‐induced morphological changes
Authors: Xu B. , McIntyre D. C. , Fahnestock M. , Racine R. J. 
Published: July 2004

AbstractGenetic deficits have been discovered in human epilepsy, which lead to alteration of the balance between excitation and inhibition, and ultimately result in seizures. Rodents show similar genetic determinants of seizure induction. To test whether seizure‐prone phenotypes exhibit increased seizure‐related morphological changes, we compared two standard rat strains (Long–Evans hooded and Wistar) and two specially bred strains following status epilepticus. The special strains, namely the kindling‐prone (FAST) and kindling‐resistant (SLOW) strains, were selectively bred based on their amygdala kindling rate. Although the Wistar and Long–Evans hooded strains experienced similar amounts of seizure activity, Wistar rats showed greater mossy fiber sprouting and hilar neuronal loss than Long–Evans hooded rats. The mossy fiber system was affected differently in FAST and SLOW rats. FAST animals showed more mossy fiber granules in the naïve state, but were more resistant to seizure‐induced mossy fiber sprouting than SLOW rats. These properties of the FAST strain are consistent with those observed in juvenile animals, further supporting the hypothesis that the FAST strain shares circuit properties similar to those seen in immature animals. Furthermore, the extent of mossy fiber sprouting was not well correlated with sensitivity to status epilepticus, but was positively correlated with the frequency of spontaneous recurrent seizures in the FAST rats only, suggesting a possible role for axonal sprouting in the development of spontaneous seizures in these animals. We conclude that genetic factors clearly affect seizure development and related morphological changes in both standard laboratory strains and the selectively bred seizure‐prone and seizure‐resistant strains.
Neurotrophic effects of BDNF on embryonic gonadotropin‐releasing hormone (GnRH) neurons
Authors: Cronin Anna S. , Horan Tracey L. , Spergel Daniel J. , Brooks A. Nigel , Hastings Michael H. , Ebling Francis J. P. 
Published: July 2004

AbstractSecretion of gonadotropin‐releasing hormone (GnRH) at the median eminence is the essential activator of the reproductive axis. The mechanisms by which embryonic GnRH neurons migrate from the olfactory placode to the preoptic area and then elaborate neurites that course through the hypothalamus to terminate at the median eminence are largely unknown. We investigated the hypothesis that GnRH neurite outgrowth is promoted by brain‐derived neurotrophic factor (BDNF) because GnRH neurites course through BDNF‐rich areas of the forebrain during their development. Confocal microscopy revealed that most (86%) cultured embryonic GnRH cells tagged with a green fluorescent protein reporter were immunoreactive for TrkB. In primary cultures of E12.5 olfactory tissue, treatment with BDNF induced a dose‐dependent increase in neurite outgrowth, but had no discernible effect on branching. BDNF induced phosphorylation of Ca2+/cAMP response element‐binding protein (pCREB) in both GnRH and non‐GnRH cells in these cultures. This was not associated with phosphorylation of ERK in GnRH‐immunoreactive cells, though BDNF treatment did stimulate pERK in neighbouring non‐GnRH cells. Promotion of neurite outgrowth is unlikely therefore to result from activation of the Ras‐MAPK/ERK pathway. We conclude that the developing GnRH secretory system is directly sensitive to BDNF and that this polypeptide functions as a neurotrophic factor for GnRH neurons.
Long‐term potentiation of transmitter exocytosis expressed by Ca2+‐induced Ca2+ release from thapsigargin‐sensitive Ca2+ stores in preganglionic nerve terminals
Authors: Cong Ya‐Lin , Takeuchi Shinpei , Tokuno Hiroyuki , Kuba Kenji 
Published: July 2004

AbstractWe have studied whether Ca2+‐induced Ca2+ release (CICR) is involved in the mechanism of long‐term potentiation (LTP) at nicotinic synapses of bullfrog sympathetic ganglia. Fast excitatory postsynaptic potentials (fast EPSPs) were recorded in a low‐Ca2+, high‐Mg2+ solution and quantal analysis was applied. The conditioning stimulation of the B‐type preganglionic nerve at 20 Hz for 4 min consistently enhanced the amplitude and quantal content of fast EPSP for > 2 h, but only sometimes enhanced the quantal size. The LTP of quantal content produced by the conditioning tetanus was blocked by thapsigargin, a blocker of Ca2+ pumps at Ca2+ stores, applied before or after the conditioning tetanus, and by Xestospongin C, a blocker of inositoltrisphosphate (IP3) receptors, applied before the tetanus. It was not, however, blocked by ryanodine, a blocker and/or activator of ryanodine receptors, or by propranolol, a blocker of β‐adrenergic receptors. Thus the long‐lasting activity of the preganglionic nerve at a high frequency causes the LTP of impulse‐evoked transmitter release by the activation of CICR from thapsigargin‐sensitive Ca2+ stores in the nerve terminals. It is likely that a large Ca2+ entry into the nerve terminals during tetanic activity primes ryanodine‐insensitive Ca2+ release channels for activation.
Mechanism of NF‐κB inactivation induced by survival signal withdrawal in cerebellar granule neurons
Authors: D. Kovács Attila , Chakraborty‐Sett Shikha , Ramirez Servio H. , Sniderhan Lynn F. , Williamson Andrea L. , Maggirwar Sanjay B. 
Published: July 2004

AbstractActivity of the transcription factor nuclear factor‐κB (NF‐κB) has been shown to be necessary for maintaining neuronal viability. In cultured rat cerebellar granule neurons, trophic factor withdrawal induces NF‐κB inactivation, resulting in cell death. The exact mechanism of this inactivation, however, has not been revealed. Here we report that trophic factor deprivation in cultured cerebellar granule neurons leads to a rapid and sustained increase in the level of IκBα and IκBβ, the inhibitory proteins of NF‐κB, causing prolonged NF‐κB inactivation. Transient NF‐κB activation resulting in new IκBα mRNA and protein synthesis gives rise to the rapid increase of IκBα level. The importance of elevated IκB level in neuronal apoptosis was confirmed in transfection experiments. Ectopic expression of a stabilized form of IκBα protein promoted neuronal death. Our findings suggest a novel mode of initiation of neuronal apoptosis wherein survival signal withdrawal induces NF‐κB to lethally turn itself off.
Distributed population coding of multisensory spatial information in the associative cortex
Authors: Benedek György , Eördegh Gabriella , Chadaide Zoltán , Nagy Attila 
Published: July 2004

AbstractThis study describes a possible mechanism of coding of multisensory information in the anterior ectosylvian visual area of the feline cortex. Extracellular microelectrode recordings on 168 cells were carried out in the anterior ectosylvian sulcal region of halothane‐anaesthetized, immobilized, artificially ventilated cats. Ninety‐five neurons were found to respond to visual stimuli, 96 responded to auditory stimuli and 45 were bimodal, reacting to both visual and auditory modalities. A large proportion of the neurons exhibited significantly different responses to stimuli appearing in different regions of their huge receptive field. These neurons have the ability to provide information via their discharge rate on the site of the stimulus within their receptive field. This suggests that they may serve as panoramic localizers. The ability of the bimodal neurons to localize bimodal stimulus sources is better than any of the unimodal localizing functions. Further, the sites of maximal responsivity of the visual, auditory and bimodal neurons are distributed over the whole extent of the large receptive fields. Thus, a large population of such panoramic visual, auditory and multisensory neurons could accurately code the locations of the sensory stimuli. Our findings support the notion that there is a distributed population code of multisensory information in the feline associative cortex.
c‐ret regulates cholinergic properties in mouse sympathetic neurons: evidence from mutant mice
Authors: Burau K. , Stenull I. , Huber K. , Misawa H. , Berse B. , Unsicker K. , Ernsberger U. 
Published: July 2004

AbstractThe search for signalling systems regulating development of noradrenergic and cholinergic sympathetic neurons is a classical problem of developmental neuroscience. While an essential role of bone morphogenetic proteins for induction of noradrenergic properties is firmly established, factors involved in the development of cholinergic traits in vivo are still enigmatic. Previous studies have shown that the c‐ret receptor and cholinergic properties are coexpressed in chick sympathetic neurons. Using in situ hybridization we show now that a loss‐of‐function mutation of the c‐ret receptor in mice dramatically reduces numbers of cells positive for choline acetyltransferase (ChAT) and the vesicular acetylcholine transporter (VAChT) in stellate ganglia of homozygous newborn animals. The number of neurons positive for tyrosine hydroxylase (TH) mRNA, the rate‐limiting enzyme of noradrenaline synthesis, is reduced to a smaller degree and expression levels are not detectably altered. Already at embryonic day 16 (E16), ChAT and VAChT‐positive cells are affected by the c‐ret mutation. At E14, however, ChAT and VAChT mRNAs are detectable at low levels and no difference is observed between wildtype and mutant mice. Our data suggest that c‐ret signalling is necessary for the maturation of cholinergic sympathetic neurons but dispensable for de novo induction of ChAT and VAChT expression.
Antinociceptive effects of N‐acetylaspartylglutamate (NAAG) peptidase inhibitors ZJ‐11, ZJ‐17 and ZJ‐43 in the rat formalin test and in the rat neuropathic pain model
Authors: Yamamoto Tatsuo , Hirasawa Serabi , Wroblewska Barbara , Grajkowska Ewa , Zhou Jia , Kozikowski Alan , Wroblewski Jarda , Neale Joseph H. 
Published: July 2004

AbstractThe peptide neurotransmitter N‐acetylaspartylglutamate (NAAG) acts as an agonist at group II metabotropic glutamate receptors (mGluRs). NAAG is inactivated by extracellular peptidase activity yielding glutamate and N‐acetylaspartate. We recently developed a series of potent NAAG peptidase inhibitors, including ZJ‐11, ZJ‐17 and ZJ‐43. In the present study, we examined the effects of intrathecally administered ZJ‐11 and ZJ‐17 and intravenously administered ZJ‐11 and ZJ‐43 in the rat formalin test (an inflammatory pain model) and in the rat partial sciatic nerve ligation model (a neuropathic pain model). Intrathecal injection of ZJ‐11 or ZJ‐17 or intravenous injection of ZJ‐11 or ZJ‐43 suppressed both phases of the agitation behaviour induced by paw formalin injection. Intrathecal and intravenous injection of ZJ‐11 suppressed the expression of Fos‐like immunoreactivity, induced by paw formalin injection, in laminae I–II in segments L4–L5 of the spinal cord, suggesting an action on sensory spinal transmission. Partial sciatic nerve ligation induced significant mechanical allodynia 7 days after the nerve injury. Intrathecal injection of ZJ‐11 or ZJ‐17 or intravenous administration of ZJ‐11 or ZJ‐43 attenuated the level of mechanical allodynia induced by this nerve ligation. These effects of intrathecally or intravenously administered ZJ compounds in both the formalin test and the partial sciatic nerve ligation model were completely antagonized by pretreatment with LY‐341495, a highly selective group II mGluR antagonist. Thus, elevation of extracellular NAAG, induced by the inhibition of NAAG peptidase, activates group II mGluRs and produces an analgesic effect in neuropathic and inflammatory and pain models. In contrast, peptidase inhibition did not affect the threshold for withdrawal from a noxious mechanical stimulus or from an acute thermal stimulus in the hotplate test.