Current difficulties in the diagnosis and management of spinal tuberculosis.

BACKGROUND: The diagnosis of spinal tuberculosis (ST) is difficult and it commonly presents at an advanced stage. The management and follow up is complicated by a lack of guidance on the appropriate use and interpretation of spinal magnetic resonance studies (MR). AIMS: A retrospective study was performed at a UK centre to identify the demographic and presenting features of a spinal TB population, their response to treatment, and the value of follow up MR studies. PATIENTS AND RESULTS: Twenty one patients were identified with mean symptom duration of 11 (1.5-36) months having been assessed by a health practitioner on 3.2 (0-10) occasions before referral for investigation for ST. Twenty were born outside the UK. Their mean duration of residence in the UK was 6.67 (0.75-20) years, and six (32%) were resident for more than 10 years. Most (85.7%) did not have a medical history and one was HIV positive. Back pain, neurological, and constitutional symptoms were found in 100%, 29%, and 38% respectively. Musculoskeletal and neurological signs were found in 29% and 19% respectively. Spinal MR performed between 6 and 12 months suggests that six months of chemotherapy (for a fully sensitive organism) may not be sufficient to achieve disease resolution. CONCLUSIONS: Awareness of the demographic, clinical, and laboratory features of an ST population may facilitate earlier diagnosis. Guidance is required on the appropriate use and interpretation of MRI in the follow up of these patients.

L-glutamate and its ionotropic receptors in the nervous system of cephalopods.

In several species of cephalopod molluscs there is good evidence for the presence of L-glutamate in the central and peripheral nervous system and evidence for both classes of ionotropic receptor, AMPA/kainate and NMDA.The best evidence for glutamate being a transmitter in cephalopods comes from pharmacological, immunohistochemical and molecular investigations on the giant fibre system in the squid stellate ganglion. These studies confirm there are AMPA/kainate-like receptors on the third-order giant axon. In the (glial) Schwann cells associated with the giant axons both classes of glutamate receptor occur.Glutamate is an excitatory transmitter in the chromatophores and in certain somatic muscles and its action is mediated primarily via AMPA/kainate-like receptors, but at some chromatophores there are NMDA-like receptors.In the statocysts the afferent crista fibres are also glutamatergic, acting at non-NMDA receptors.In the brain (of Sepia) a neuronal NOS is activated by glutamate with subsequent production of nitric oxide and elevation of cGMP levels. This signal transduction pathway is blocked by D-AP-5, a specific antagonist of the NMDA receptor.Recently immunohistochemical analysis has demonstrated (in Sepia and Octopus) the presence of NMDAR2A /B - like receptors in motor centres, in the visual and olfactory systems and in the learning system. Physiological experiments have shown that glutamatergic transmission is involved in long term potentation (LTP) in the vertical lobe of Octopus, a brain area involved in learning. This effect seems to be mediated by non-NMDA receptors. Finally in the CNS of Sepia NMDA-mediated nitration of tyrosine residues of cytoskeletal protein such as alpha-tubulin, has been demonstrated.

Mitochondrial phylogeography and population history of pine martens Martes martes compared with polecats Mustela putorius.

The flora and fauna of Europe are linked by a common biogeographic history, most recently the Pleistocene glaciations that restricted the range of most species to southern refugial populations. Changes in population size and migration, as well as selection, have all left a signature on the genetic differentiation. Thus, three paradigms of postglacial recolonization have been described, inferred from the patterns of DNA differentiation. Yet some species, especially wide-ranging carnivores, exhibit little population structuring between the proposed refugia, although relatively few have been studied due to the difficulty of obtaining samples. Therefore, we investigated mitochondrial variation in pine martens, Martes martes, in order to understand the extent to which they were affected by glacial cycles, and compared the results with an analysis of sequences from polecats, Mustela putorius. A general lack of ancient lineages, and a mismatch distribution that is consistent with an expanding population, is evidence that the present-day M. martes and Mu. putorius in central and northern Europe colonized from a single European refugium following a recent glaciation. There has also been interspecific mitochondrial introgression between M. martes and the sable M. zibellina in Fennoscandia.

Efficacy of postdeployment balloon dilatation for current generation stents as assessed by intravascular ultrasound.

Adjunctive balloon dilatation strategy has been shown to improve optimal stent deployment. As improvements in current stent designs evolve, less adjunctive balloon dilatation may be needed. However, few data currently exist to support this practice. We evaluated 88 native coronary lesions treated with single stent implantation (Nir, Tristar or S670). Serial intravascular ultrasound was performed after successful stent deployment and again after adjunctive balloon dilatation. To investigate further the precise expansion characteristics of the stents, serial volumetric intravascular ultrasound analyses were performed in 40 patients with automated pullback. After adjunctive balloon dilatation, minimal stent area increased significantly, from 6.4 +/- 2.1 to 7.4 +/- 2.2 mm(2) (p <0.001). Volumetric analysis showed a corresponding increase in stent volume index (6.6 +/- 1.8 to 7.5 +/- 2.0 mm(3)/mm, p <0.001). In the analysis of cross sections at 0.5-mm axial intervals, the percentage of cross sections, where stent area was > or =80% of the average reference lumen area, increased from 51% to 78% (p <0.001). Similarly, the percentage of cross sections, where stent area was > or =90% of the average reference lumen area, increased from 29% to 56% (p <0.001) with postdilatation. Postdeployment high- pressure balloon dilatation improved minimal stent area and volumetric expansion throughout the stented segment.

Development and reorganization of corticospinal projections in EphA4 deficient mice.

The Eph family of receptor tyrosine kinases and their ligands, the ephrins, are important regulators of axon guidance and cell migration in the developing nervous system. Inactivation of the EphA4 gene results in axon guidance defects of the corticospinal tract, a major descending motor pathway that originates in the cortex and terminates at all levels of the spinal cord. In this investigation, we report that although the initial development of the corticospinal projection is normal through the cortex, internal capsule, cerebral peduncle, and medulla in the brain of EphA4 deficient animals, corticospinal axons exhibit gross abnormalities when they enter the gray matter of the spinal cord. Notably, many corticospinal axons fail to remain confined to one side of the spinal cord during development and instead, aberrantly project across the midline, terminating ipsilateral to their cells of origin. Given the possible repulsive interactions between EphA4 and one of its ligands, ephrinB3, this defect could be consistent with a loss of responsiveness by corticospinal axons to ephrinB3 that is expressed at the spinal cord midline. Furthermore, we show that EphA4 deficient animals exhibit ventral displacement of the mature corticospinal termination pattern, suggesting that developing corticospinal axons, which may also express ephrinB3, fail to be repelled from areas of high EphA4 expression in the intermediate zone of the normal spinal cord. Taken together, these results suggest that the dual expression of EphA4 on corticospinal axons and also within the surrounding gray matter is very important for the correct development and termination of the corticospinal projection within the spinal cord.

Differential expression of functionally identified and immunohistochemically identified NK(1) receptors on sympathetic neurons.

We have used multiple-labeling immunohistochemistry, intracellular dye-filling, and intracellular microelectrode recordings to characterize the distribution of tachykinin receptors and substance P boutons on subpopulations of neurons within the guinea pig celiac ganglion. Superfusion of substance P (SP, 1 microM for 1 min) depolarized 42% of tonic neurons and inhibited afterhyperpolarizations in 66% of long afterhyperpolarizing (LAH) neurons without significant desensitization. Twenty-one percent of tonic neurons and 24% of LAH neurons responded to the NK(3) agonist senktide but did not respond to SP, indicating SP did not activate NK(3) receptors at this concentration. All effects of SP were abolished by the selective NK(1) receptor antagonist, SR140333, but not by the selective NK(3) receptor antagonist, SR142801, suggesting that exogenous SP activated a receptor with NK(1) pharmacology. No dye-filled LAH neuron and only 50% of tonic neurons responding to SP expressed NK(1) receptor immunoreactivity (NK(1)-IR). All neurons responding to SP had SP immunoreactive fibers within one cell diameter, indicating good spatial matching between SP release sites and target neurons. These results indicate that SP may act via a receptor with NK(1)-like pharmacology that has a C terminus not recognized by antibodies to the intracellular domain of the conventional NK(1) receptor. Inward currents evoked by SP acting on this NK(1)-like receptor or senktide acting through NK(3) receptors had identical current-voltage relationships. In LAH neurons, both agonists suppressed I(sAHP) without reducing I(AHP). Responses evoked by SP and senktide were resistant to PKC inhibitors, suggesting that the transduction mechanisms for the NK(1)-like receptor and the NK(3) receptor may be similar.

Hair density, hair diameter and the prevalence of female pattern hair loss.

BACKGROUND: Female pattern hair loss is common but estimates of its prevalence have varied widely. The relationships between the clinical diagnosis of female pattern hair loss and objective measurements of hair density and hair diameter have not previously been evaluated. OBJECTIVES: To determine the prevalence of female pattern hair loss and to relate the clinical findings to hair density and hair diameter. METHODS: We examined 377 women, aged 18--99 years, who presented to a general dermatology clinic with complaints unrelated to hair growth (the unselected sample). A second group of 47 women referred with typical female pattern hair loss was included in analyses of the relationships between hair density, hair diameter and the clinical diagnosis. Hair density was measured using a photographic method. In each subject the major and minor axis diameters were measured in a random sample of 50 hairs. RESULTS: Six per cent of women aged under 50 years were diagnosed as having female pattern hair loss, increasing to 38% in subjects aged 70 years and over. The mean +/- SEM hair density was 293 +/- 61.3 hairs cm(-2) at age 35 years, falling to 211 +/- 55.1 hairs cm(-2) at age 70 years. Hair density showed a normal distribution in the unselected sample. Most women classified as having female pattern hair loss had hair densities within the lower half of the normal distribution. The perception of hair loss was determined mainly by low hair density (ANOVA P < 0.001), but there was overlap in hair density between women classified as having Ludwig I hair loss and the no hair loss group, which was partly accounted for by differences in mean hair diameter (ANOVA P < 0.001). Low hair density was associated with fewer hairs of all diameters. CONCLUSIONS: Hair density in women is distributed as a normal variable, indicating that it is determined as a multifactorial trait. Women with female pattern hair loss have a hair density which falls below the mean but lies within the spectrum of the normal distribution, although other factors, including hair diameter, may affect the subjective impression of hair loss. The hair diameter data suggest that low hair density is not due to progressive diminution in hair follicle size and that follicular miniaturization may occur within the space of a single hair cycle.

Population-based survey and analysis of trends in the prevalence of diabetic nephropathy in Type 1 diabetes.

AIMS: To determine the prevalence of the various stages of diabetic nephropathy in Type 1 diabetes in a population-based survey. To make direct comparison with results from previous published studies to assess current trends. METHODS: Identification of all Type 1 patients using a population-based diabetes register. Urine samples for albumin assay were obtained at clinic visit and by postal request. Prevalence rates were calculated specifically for direct comparisons with previously published surveys. RESULTS: This study and European data from the 1990s show a clear reduction in the cumulative prevalence of microalbuminuria and established nephropathy compared with surveys from Copenhagen (1985), Pittsburgh (1986-8) and Boston (1992). In North Wales in 1999 the overall cumulative prevalence of microalbuminuria was 27.2% (95% confidence interval (CI) 24.3-30.1%) and established nephropathy was 9.6% (7.7-11.5%). Comparisons with data from EURODIAB and from Spain indicated similar results, although the prevalence of microalbuminuria was lower in North Wales than in the EURODIAB study. Significantly lower rates of nephropathy were seen in more recent Swedish cohorts. Diabetic nephropathy remains more common in males. Microalbuminuria before 10 years duration of diabetes was seen at all post-pubertal ages. CONCLUSIONS: Rates of nephropathy in Europe in the 1990s are lower than a decade ago. Modern methods of management are therefore associated with demonstrable benefit at the population level. The lowest rates of nephropathy are associated with optimum glycaemic control in Swedish data, indicating the importance of metabolic in addition to haemodynamic factors.

Cephalopod chromatophores: neurobiology and natural history.

The chromatophores of cephalopods differ fundamentally from those of other animals: they are neuromuscular organs rather than cells and are not controlled hormonally. They constitute a unique motor system that operates upon the environment without applying any force to it. Each chromatophore organ comprises an elastic sacculus containing pigment, to which is attached a set of obliquely striated radial muscles, each with its nerves and glia. When excited the muscles contract, expanding the chromatophore; when they relax, energy stored in the elastic sacculus retracts it. The physiology and pharmacology of the chromatophore nerves and muscles of loliginid squids are discussed in detail. Attention is drawn to the multiple innervation of dorsal mantle chromatophores, of crucial importance in pattern generation. The size and density of the chromatophores varies according to habit and lifestyle. Differently coloured chromatophores are distributed precisely with respect to each other, and to reflecting structures beneath them. Some of the rules for establishing this exact arrangement have been elucidated by ontogenetic studies. The chromatophores are not innervated uniformly: specific nerve fibres innervate groups of chromatophores within the fixed, morphological array, producing 'physiological units' expressed as visible 'chromatomotor fields'. The chromatophores are controlled by a set of lobes in the brain organized hierarchically. At the highest level, the optic lobes, acting largely on visual information, select specific motor programmes (i.e. body patterns); at the lowest level, motoneurons in the chromatophore lobes execute the programmes, their activity or inactivity producing the patterning seen in the skin. In Octopus vulgaris there are over half a million neurons in the chromatophore lobes, and receptors for all the classical neurotransmitters are present, different transmitters being used to activate (or inhibit) the different colour classes of chromatophore motoneurons. A detailed understanding of the way in which the brain controls body patterning still eludes us: the entire system apparently operates without feedback, visual or proprioceptive. The gross appearance of a cephalopod is termed its body pattern. This comprises a number of components, made up of several units, which in turn contains many elements: the chromatophores themselves and also reflecting cells and skin muscles. Neural control of the chromatophores enables a cephalopod to change its appearance almost instantaneously, a key feature in some escape behaviours and during agonistic signalling. Equally important, it also enables them to generate the discrete patterns so essential for camouflage or for signalling. The primary function of the chromatophores is camouflage. They are used to match the brightness of the background and to produce components that help the animal achieve general resemblance to the substrate or break up the body's outline. Because the chromatophores are neurally controlled an individual can, at any moment, select and exhibit one particular body pattern out of many. Such rapid neural polymorphism ('polyphenism') may hinder search-image formation by predators. Another function of the chromatophores is communication. Intraspecific signalling is well documented in several inshore species, and interspecific signalling, using ancient, highly conserved patterns, is also widespread. Neurally controlled chromatophores lend themselves supremely well to communication, allowing rapid, finely graded and bilateral signalling.

Nitric oxide synthase (NOS) in the brain of the cephalopod Sepia officinalis.

Nitric oxide synthase-like protein (NOS) is shown to be present in specific regions of the central nervous system (CNS) of the cephalopod mollusc Sepia officinalis (cuttlefish). NOS activity, which is Ca(2+)/calmodulin-dependent, was determined by measuring the conversion of L-[(14)C]arginine in L-[(14)C]citrulline. The partially purified NOS from brain and optic lobes exhibited on SDS-PAGE a band at 150 kDa that was immunolabelled by antibodies raised against the synthetic peptide corresponding to the amino acids 1,414-1,429 of the C-terminus of rat nNOS. This same antibody was then used for immunohistochemical staining of serial sections of the cuttlefish CNS to reveal localized specific staining of cell bodies and fibers in several lobes of the brain. Staining was found in many lower motor centers, including cells and fibers of the inferior and superior buccal lobes (feeding centers); in some higher motor centers (anterior basal and peduncle lobes); in learning centers (vertical, subvertical, and superior frontal lobes); and in the visual system [retina and deep retina (optic lobe)]. Immunopositivity was also found in the olfactory lobe and organ and in the sucker epithelium. These findings suggest that nitric oxide (NO) may be involved as a signaling molecule in feeding, motor, learning, visual, and olfactory systems in the cuttlefish brain. The presence of NOS in the cephalopod "cerebellum" and learning centers is discussed in the context of the vertebrate CNS.

Neuronal morphology and the synaptic organisation of sympathetic ganglia.

In this article, we provide a short review of the structure and synaptic organisation of the final motor neurons in the sympathetic ganglia of mammals. Combinations of pathway tracing, multiple-labelling immunofluorescence and intracellular dye injection have shown that neurons in different functional pathways differ not only in their patterns of neuropeptide expression, but also in the size of their cell bodies and dendritic fields. Thus, vasoconstrictor neurons consistently are smaller than any other major functional class of neurons. Serial section ultrastructural analysis of dye filled neurons, together with electron microscopic and confocal microscopic analysis of immunolabelled synaptic inputs to sympathetic final motor neurons indicate that synapses are rare and randomly distributed over the surface of the neurons. The total number of synapses is simply proportional to the total surface area of the neurons. Many terminal boutons of peptide-containing preganglionic neurons do not make conventional synapses with target neurons. Furthermore, there is a spatial mismatch in the distribution of peptide-containing terminals and neurons expressing receptors for the corresponding peptides. Together, these results suggest that there are likely to be significant differences in the ways that the final sympathetic motor neurons in distinct functional pathways integrate their synaptic inputs. In at least some pathways, heterosynaptic actions of neuropeptides probably contribute to subtle modulation of ganglionic transmission.

3D coronary reconstruction from routine single-plane coronary angiograms: clinical validation and quantitative analysis of the right coronary artery in 100 patients.

BACKGROUND: Current coronary angiographic techniques display complex three-dimensional (3D) coronary structures in two dimensions (2D). We have developed a 3D reconstruction (3DR) algorithm using standard single-plane angiographic images that allows for 3D display of coronary structures. The purpose of this study was to validate our 3DR algorithm and quantify anatomic characteristics of the right coronary artery (RCA) in vivo. METHODS: Accuracy and reproducibility studies were performed using 3DRs of a coronary phantom and in vivo following 3DRs in 40 patients. The anatomic features of the RCA were then quantified in 100 patients. RESULTS: Comparison of length and bifurcation angles (BA) from the phantom to the 3DRs revealed good accuracy and correlation for both (r = 0.95 and 0.93 respectively), with diameter error of < 7%. In vivo, the average root mean square (RMS) error in the spatial coordinates of the vessel centerlines was 3.12 +/- 0.77 and 3.16 +/- 0.75 mm in 20 left coronary arteries (LCA) and 20 RCAs respectively. Interobserver average RMS error was 3.47 +/- 1.96 mm and intraobserver average RMS error was 3.02 +/- 1.07 and 3.44 +/- 1.57 mm for two different operators (p = NS). The average RCA length was 10.2 +/- 1.7 cm, average radius of curvature (ROC) was 52 +/- 9 degrees, and the average 3D bifurcation angle of the posterior descending artery (PDA) from the RCA was 55 +/- 22 degrees. Foreshortening (FS) of the segments of the RCA in three 'standard' projections ranged from 0-60, 0-75, and 0-82% respectively. CONCLUSIONS: Using our 3DR algorithm patient-specific anatomic characteristics can be accurately displayed and quantified, expanding the information that can be derived from routine coronary angiography.

Transesophageal echocardiographic visualization of left ventricular malpositioned pacemaker electrodes: implications for lead extraction procedures.

Two cases of malpositioned LV electrodes are presented. Transesophageal echocardiography (TEE) allowed for a careful inspection of left-sided leads and for tracking their course. One LV and two right-sided leads were safely retrieved with TEE monitoring. One chronic LV lead was left in place as it was heavily fibrosed. TEE was helpful in the inspection and monitoring of the extraction and also in guided traction efforts. This is the first published report of echocardiographic visualization of the lead retrieval procedure.

Localization of L-glutamate and glutamate-like receptors at the squid giant synapse.

HPLC analysis of the amino acid contents of the second- and third-order giant fibres at the giant synapse in the stellate ganglion of the squid Loligo vulgaris shows that there are significantly higher amounts of L-glutamate and L-aspartate in the second-order (presynaptic) fibre than in the third-order (postsynaptic) fibre. Immunocytochemical staining of sections of the ganglion with an antibody raised against L-glutamate produces specific positive staining in the synaptic region of the second-order fibre. In contrast, staining with antibodies raised against glutamate-receptors (mammalian GluR1 with GluR2/3) produces positive staining in the third-order fibre at the postsynaptic region. These data provide further evidence for the hypothesis that L-glutamate is an excitatory transmitter at the giant synapse.

Neurokinin-1 receptor localisation in guinea pig autonomic ganglia.

We have used multiple-labelling immunohistochemistry and confocal microscopy to determine the distribution of immunoreactivity to the tachykinin neurokinin-1 (NK(1)) receptors in guinea pig sympathetic ganglia. Although nerve fibres containing immunoreactivity to substance P were common in all ganglia except the superior cervical ganglia, most neurons expressing NK(1) receptor immunoreactivity were not closely surrounded by pericellular baskets of substance P-immunoreactive boutons. Conversely, many neurons surrounded by baskets of substance P-immunoreactive boutons lacked NK(1) immunoreactivity. In the coeliac and inferior mesenteric ganglia, NK(1) receptor expression was restricted almost entirely to noradrenergic neurons that contained somatostatin immunoreactivity and projected to the enteric plexuses. In the lumbar chain and paracervical ganglia, NK(1) immunoreactivity was expressed by nonnoradrenergic vasodilator neurons containing immunoreactivity to vasoactive intestinal peptide. Taken together, our results show that sympathetic neurons in different functional pathways express NK(1) receptor immunoreactivity. However, the neurons that could respond to endogenously released substance P through NK(1) receptors may be distant from presynaptic release sites. These observations suggest that, in sympathetic ganglia, substance P may modulate ganglionic transmission through heterosynaptic actions on NK(1) receptors.

Hyperbaric oxygen and thrombolysis in myocardial infarction: the 'HOT MI' randomized multicenter study.

In a previous pilot study, we demonstrated that adjunctive treatment with hyperbaric oxygen (HBO) appears to be feasible and safe in patients with acute myocardial infarction (AMI) and may result in an attenuated rise in creatine phosphokinase (CPK), more rapid resolution of pain and ST changes. This randomized multicenter trial was organized to further assess the safety and feasibility of this treatment in human subjects. Patients with an AMI treated with recombinant tissue plasminogen activator (rTPA) or streptokinase (STK), were randomized to treatment with HBO combined with either rTPA or STK, or rTPA or STK alone. An analysis included 112 patients, 66 of whom had inferior AMIs (p = NS). The remainder of the patients had anterior AMIs. The mean CPK at 12 and 24 h was reduced in the HBO patients by approximately 7.5% (p = NS). Time to pain relief was shorter in the HBO group. There were 2 deaths in the control and 1 in those treated with HBO. The left ventricle ejection fraction (LVEF) on discharge was 51.7% in the HBO group as compared to 48.4% in the controls (p = NS). The LVEF of the controls was 43.4 as compared to 47.6 for those treated, approximately 10% better (no significant difference). Treatment with HBO in combination with thrombolysis appears to be feasible and safe for patients with AMI and may result in an attenuated CPK rise, more rapid resolution of pain and improved ejection fractions. More studies are needed to assess the benefits of this treatment.

Differential distribution of substance P binding sites in guinea-pig sympathetic ganglia.

We have used a combination of autoradiographic and immunohistochemical techniques to investigate the distribution of binding sites for substance P in relation to the distribution of substance P-immunoreactive nerve fibres and specific functional populations of neurons in the sympathetic ganglia of guinea-pigs. There was considerable heterogeneity in the density of binding sites for Bolton Hunter labelled 125I - substance P (BHSP). Binding sites were more dense in the prevertebral ganglia, such as the coeliac and inferior mesenteric ganglia, than in the paravertebral ganglia, such as the superior cervical or lumbar chain ganglia. The binding sites tended to be clumped within the ganglia. Within the prevertebral ganglia, they were associated predominantly with neurons projecting to the enteric plexuses. Many of these neurons contained somatostatin immunoreactivity. In the lumbar sympathetic chain ganglia, there was a weak association of binding sites with neurons containing immunoreactivity to vasoactive intestinal peptide. Overall, the density of binding sites matched the density of nerve fibres containing immunoreactivity to substance P in different ganglia. However, within particular ganglia, there was little, if any, correlation between the distribution of binding sites and nerve fibres containing substance P. Most of the binding sites in the ganglia had the pharmacological characteristics of NK1 receptors. Our results show that there is considerable heterogeneity in the expression of NK1 receptors in the sympathetic ganglia of guinea-pigs. However, given the relatively poor spatial correlation between the distribution of binding sites and potential sites of substance P release from intraganglionic nerve fibres, we suggest that substance P may diffuse for relatively large distances through the ganglia, with actions only on those neurons selectively expressing NK1 receptors.

Hyperbaric oxygen and thrombolysis in myocardial infarction: the "HOT MI" pilot study.

Hyperbaric oxygen treatment (HBO) in combination with thrombolysis has been demonstrated to salvage myocardium in acute myocardial infarction in the animal model. Therefore a randomized pilot trial was undertaken to assess the safety and feasibility of this treatment in human beings. Patients with an acute myocardial infarction (AMI) who received recombinant tissue plasminogen activator (rTPA) were randomized to treatment with HBO combined with rTPA or rTPA alone. Sixty-six patients were included for analysis. Forty-three patients had inferior AMIs (difference not significant) and the remainder had anterior AMIs. The mean creatine phosphokinase level at 12 and 24 hours was reduced in the patients given HBO by approximately 35% (p = 0.03). Time to pain relief and ST segment resolution was shorter in the group given HBO. There were two deaths in the control group and none in those treated with HBO. The ejection fraction on discharge was 52.4% in the group given HBO compared with 47.3% in the control group (difference not significant). Adjunctive treatment with HBO appears to be a feasible and safe treatment for AMI and may result in an attenuated rise in creatine phosphokinase levels and more rapid resolution of pain and ST segment changes.

Nitric oxide synthase- and neuropeptide Y-containing subpopulations of sympathetic neurons in the coeliac ganglion of the Atlantic cod, Gadus morhua, revealed by immunohistochemistry and retrograde tracing from the stomach.

In this study retrograde tracing was used to locate sympathetic ganglion cells innervating the stomach of a teleost fish, Gadus morhua. A subpopulation of small neurons in the coeliac ganglion was retrogradely labelled after Fast Blue injection in the stomach wall. Neurons projecting to the myenteric plexus and muscle layers contained tyrosine hydroxylase immunoreactivity, and neurons projecting to submucosal layers and blood vessels contained neuropeptide Y immunoreactivity in addition to being tyrosine hydroxylase immunoreactive. A population of nitric oxide synthase containing tyrosine hydroxylase immunoreactive neurons was also found in the coeliac ganglion. These neurons were not frequently labelled after injection in any layer of the stomach. The presence of entero-enteric pathways was also surveyed, but too few enteric neurons were labelled with Fast Blue after injection in the coeliac ganglion to indicate a presence of an entero-enteric reflex. We conclude that in teleost fish, as previously reported in a variety of mammals, a pattern of target specific chemical coding of sympathetic neurons exists, but that all reflex systems of mammalian vertebrates are perhaps not present in fish.