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Two new deep-living species of the genus Bargmannia (Siphonophorae, Physonectae, Pyrostephidae) are described based, almost exclusively, on the nectophores of single specimens collected by ROVs off the west coast of California. The nectophores of B. stenotes sp. nov. were relatively small, up to 11.4 mm in length and, in the preserved condition had very narrow nectosacs. There was a marked bend in the distal part of the preserved nectophore, resulting in the ostium opening upwards. The mature nectophores of B. profunda sp. nov. were almost twice as long as those of B. stenotes and were characterised by the fact that the lower lateral ridges did not join, distally, with the meso-lateral ones. This feature also was present in smaller nectophores of B. amoena but those of B. stenotes, at that stage, did not have a mouth-plate.

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In his Challenger Monograph Haeckel (1888b) listed a total of 204 species of siphonophores and 36 species of Porpitidae (Disconectae, according to Haeckel), which are now known not to belong to the Siphonophorae. In this paper the siphonophore species have been divided into four categories: a). species that had been described previously by an acknowledged authority other than Haeckel; b). species where Haeckel changed the generic or specific name of a previously described species by another authority, and then ascribed the authority to himself; c). species that Haeckel actually described and illustrated as what he believed to be new; and d). species that Haeckel mentioned in the text as a new species, but with the description deferred to a later publication or simply not given. The validity of the forty-three species that Haeckel actually described is then discussed. A full list of all these species is given in an Appendix.

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The siphonophore sub-order Cystonectae presently comprises just five species in three genera and two families, and includes Physalia physalis, the Portuguese Man O'War. Despite the smallness of the group its history has been very chequered, particularly for P. physalis, which has been described under more than fifty different names. Haeckel (1888) was one of the worst offenders regarding the description of questionable species, but even Totton (1965) was uncertain as to the validity of some previously described cystonect species. Herein, an attempt has been made to review the history of the sub-order Cystonectae and to clarify its taxonomy. A list of synonyms for each recognised cystonect species is given in an appendix.

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A new species of calycophoran siphonophore, Tottonophyes enigmatica gen. nov, sp. nov., is described. It has a unique combination of traits, some shared with prayomorphs (including two rounded nectophores) and some with clausophyid diphyomorphs (the nectophores are dissimilar, with one slightly larger and slightly to the anterior of the other, and both possess a somatocyst). Molecular phylogenetic analyses indicate that the new species is the sister group to all other diphyomorphs. A new family, Tottonophyidae, is established for it. Its phylogenetic position and distinct morphology help clarify diphyomorph evolution. The function and homology of the nectophoral canals and somatocyst is also re-examined and further clarification is given to their nomenclature.

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Two new Erenna species, E. insidiator sp. nov. and E. sirena sp. nov., are described from specimens collected in the vicinity of Monterey Bay, California, and also, for E. sirena at the southern end of the Gulf of California, Mexico. Further information on the three extant Erenna species is given, based on specimens collected in the same areas. These have enabled, for instance, the identification of three types of tentilla on the tentacles of E. cornuta Pugh, 2001, rather than the two noted on the single previously known specimen. The genus is remarkable for the presence of bioluminescent lures on the tentilla of all five species. In E. sirena sp. nov. the tentilla are also covered by a red-fluorescent layer, which was briefly described by Haddock et al. (2005), and further details are given herein. Another extraordinary feature of the colonies E. sirena sp. nov. is that the main part of the tentacle, with its tentilla, can be extended away from the siphosomal stem on a long peduncle. This phenomenon also appears to occur in E. laciniata Pugh, 2001, and has not been observed before for other physonect species.

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The genus Cordagalma is reviewed and a re-description given of one of the extant species, C. ordinatum (Haeckel). In addition, four new species are described in the genus Cordagalma, namely C. abyssorum sp. nov., C. bimaculatum sp. nov., C. isocarrei sp. nov. and C. rugosum sp. nov. All these species have similar larval-type tentilla. A fifth new species, which has extraordinary tentilla, with an involucrum forming two flaps, is placed in a new genus Cardianecta gen. nov. as C. parchelion sp. nov. The significant differences that all these species have from other physonects is considered to warrant the establishment of the family Cordagalmatidae fam. nov. for them. This family is diagnosed purely on the presence of heart-shaped nectophores budded on the ventral side of the nectosome.

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Selective serotonin reuptake inhibitor (SSRI) antidepressants are the mainstay treatment for the 10-20% of pregnant and postpartum women who suffer major depression, but the effects of SSRIs on their children's developing brain and later emotional health are poorly understood. SSRI use during pregnancy can elicit antidepressant withdrawal in newborns and increase toddlers' anxiety and social avoidance. In rodents, perinatal SSRI exposure increases adult depression- and anxiety-like behavior, although certain individuals are more vulnerable to these effects than others. Our study establishes a rodent model of individual differences in susceptibility to perinatal SSRI exposure, utilizing selectively bred Low Responder (bLR) and High Responder (bHR) rats that were previously bred for high versus low behavioral response to novelty. Pregnant bHR/bLR females were chronically treated with the SSRI paroxetine (10 mg/kg/day p.o.) to examine its effects on offspring's emotional behavior and gene expression in the developing brain. Paroxetine treatment had minimal effect on bHR/bLR dams' pregnancy outcomes or maternal behavior. We found that bLR offspring, naturally prone to an inhibited/anxious temperament, were susceptible to behavioral abnormalities associated with perinatal SSRI exposure (which exacerbated their Forced Swim Test immobility), while high risk-taking bHR offspring were resistant. Microarray studies revealed robust perinatal SSRI-induced gene expression changes in the developing bLR hippocampus and amygdala (postnatal days 7-21), including transcripts involved in neurogenesis, synaptic vesicle components, and energy metabolism. These results highlight the bLR/bHR model as a useful tool to explore the neurobiology of individual differences in susceptibility to perinatal SSRI exposure.

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Re-descriptions are given for all the known species in the siphonophore physonect genera Halistemma (Family Agalmatidae) and Stephanomia (Family Stephanomiidae fam. nov.) based almost entirely on specimens collected by submersibles or ROVs. A new Halistemma species, H. maculatum sp. nov., is also described. Until now two of the Halistemma species were known only from incomplete specimens, such that for one, H. cupulifera Lens & van Riemsdijk, only the tentilla had been described, while for the other, H. striata Totton, only the nectophores were known. The species Stephanomia amphytridis Lesueur & Petit, originally established on the basis of only an illustration of part of the siphosome, is poorly known and several descriptions in the past have been based on further siphosomal material that actually belonged to a species of Halistemma. A specimen of that species, which included the nectosome, was recently described by Mapstone (2004) as H. amphytridis, but Pugh (2006) considered that it actually belonged to H. foliacea Quoy & Gaimard. That specimen has been re-examined for this study. The taxonomic position of the two genera is discussed. Although only distantly related the species of the two genera have a post-larval form referred to as the Nectalia stage. Haeckel (1888b) originally described a specimen at this stage as a separate species, Nectalia loligo. Nectalia stage specimens of two Halistemma species and of S. amphytridis were present in the material and their relationship with Haeckel's specimen is discussed.

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The increasing use of implantable electronic devices such as cardiac pacemakers and neurostimulators means that they are being increasingly encountered in endoscopy departments. The electromagnetic fields generated during electrosurgery and with magnetic imaging systems have the potential to interfere with such devices. The authors present a case that highlights some of the steps necessary for minimising risk, review the evidence and summarise the currently available guidance.

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BACKGROUND: Stroke is often unexplained in younger adults, although it is often associated with a patent foramen ovale (PFO). The reason for the association is not fully explained, and mechanisms other than paradoxical embolism may be involved. Young stroke patients with PFO have more atrial vulnerability than those without PFO. It is plausible that stretching of the interatrial septum may disrupt the interatrial conduction pathways causing interatrial block (IAB). IAB is associated with atrial fibrillation, dysfunctional left atria and stroke. METHODS: Electrocardiogram (ECG) characteristics of prospectively recruited young patients (≤55 years of age) with unexplained stroke (TOAST and A-S-C-O) were compared with control data. All stroke cases underwent bubble contrast transthoracic and transoesophageal echography. IAB was defined as a P-wave duration of ≥110 ms. ECG data were converted to electronic format and analysed in a blind manner. RESULTS: Fifty-five patients and 23 datasets were analysed. Patients with unexplained stroke had longer P-wave duration (p = 0.013) and a greater prevalence of IAB (p = 0.02) than healthy controls. Case status was an independent predictor of P-wave duration in a significant multivariate model. There was a significant increase in the proportion of cases with a PFO with IAB compared with cases without PFO and with controls (p = 0.005). CONCLUSIONS: Young patients with unexplained stroke, particularly those with PFO, exhibit abnormal atrial electrical characteristics suggesting atrial arrhythmia or atrial dysfunction as a possible mechanism of stroke.

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INTRODUCTION: Repeat cardioversion may be necessary in over 50% of patients with persistent atrial fibrillation (AF), but identifying responders remains challenging. This study evaluates the long-term success of direct current cardioversion (DCCV) and the clinical and echocardiographical parameters that influence them, in over 1000 sedation-cardioversion procedures undertaken at Eastbourne General Hospital between 1996 and 2006. METHODS: A total of 770 patients of mean age (SD) 70.1(10.1) underwent 1013 DCCVs (first n = 665, repeat n = 348) for atrial tachyarrhythmias from 1996 to 2006. Time to persistent arrhythmia recurrence was compared between first and multiple DCCV, and the effect of age, gender, presence of heart disease, left atrial size, fractional shortening, arrhythmia duration, anti-arrhythmic drug therapy (AAD) and other concomitant cardiac medication was evaluated using the Kaplan-Meier method and Cox's Proportional-hazards model. RESULTS: In all, 33% of first and 29% of repeat DCCVs were in sinus rhythm (SR) at 12 months (m). There was no difference in median time to arrhythmia recurrence (SE) between first and multiple procedures: 1.5 +/- 0.1 m (1.3-1.7) and 1.5 +/- 0.0 m (1.4-1.6) respectively, p = 0.45. AAD use was significantly higher, arrhythmia duration shorter and more diabetic patients underwent repeat procedures. Amiodarone, OR 0.56, p = 0.04, sotalol, OR 0.61, p = 0.02 and arrhythmia duration, < 6 m, OR 0.72, p = 0.03 were independent predictors of improved outcome in first procedures only. In patients undergoing first procedures on amiodarone or sotalol, median time to arrhythmia recurrence was longer and 12 m SR rates higher, 6.0 +/- 2.4 m (42%) than those who had a repeat procedure on the same medication, 1.5 +/- 0.1 m (33%), p = 0.06. CONCLUSIONS: The efficacy of first and subsequent DCCV procedures is similar, achieving a similar proportion of SR maintenance at 1 year. However, the benefits of AAD therapy are the greatest following first time procedures. Concomitant AAD therapy should be considered for all first time procedures for persistent AF.

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BACKGROUND: Testosterone is recognized to elicit vasodilatation in numerous vascular beds, however to date no study has investigated whether testosterone has this effect in the human pulmonary vasculature. AIM: To determine whether isolated human pulmonary arteries and veins dilate in response to testosterone and whether the response differs in relation to gender, endothelial function or location with the pulmonary vasculature. METHODS: Intralobar pulmonary arteries [no.=44, diameter =581 (349) microm] and veins [no.=27, diameter =573 (302) microm] were dissected from lobectomy samples obtained from male and female patients [no.=40, age =69 (8) yr]. Vessels were mounted in an automated wire myograph, bathed in physiological saline at 37 C and pH 7.4, and loaded to their in vivo pressure. Vessels were preconstricted with noradrenaline (10 microM) and exposed to acetylcholine (1 microM) to assess endothelial function, washed and then preconstricted with potassium chloride (1-100 mM) followed by either cumulative concentrations of testosterone (1 nM-100 microM) or ethanol vehicle (<0.1%). RESULTS: Significant marked vasodilatation was seen in all vessels, irrespective of size, gender and endothelial function at micromolar concentrations. Testosterone triggered significant vasodilatation at concentrations > or = 10 nM in pulmonary arteries obtained from males, a response which was not observed in vessels from females. The maximal response at 100 microM was also significantly greater in male pulmonary arteries. Significant vasodilatation was only observed at physiological (nM) concentrations in pulmonary resistance arteries and pulmonary arteries with good endothelial function. CONCLUSION: Testosterone acts as an efficacious vasodilator in the human pulmonary vasculature, with dilatation observed at physiological concentrations in the male arterial resistance bed, dependent on the presence of an intact endothelium.

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OBJECTIVES: To examine the relationship between serum levels of inflammatory cytokines and testosterone in men with stable coronary artery disease (CAD). Evidence supports a beneficial effect of testosterone upon objective measures of myocardial ischaemia in men with CAD, and in animal models of atherosclerosis. Inflammatory cytokines are involved in many stages of the atherosclerotic process, however, the effect of testosterone upon inflammatory cytokines within the cardiovascular system is largely unknown. METHODS: Serum was collected from 69 men (59+/-1 years) having >75% occlusion of 1, 2, or 3 coronary arteries. Levels of total testosterone (TT), bioavailable testosterone (BT), tumour necrosis factor-alpha (TNFalpha), interleukin (IL)-1-beta (IL-1beta), IL-6 and IL-10 were measured and analysis made between men with 1, 2, or 3 vessel CAD, and between men with hypogonadal, borderline hypogonadal and eugonadal serum levels of testosterone. RESULTS: In patients with 1, 2, or 3 vessel CAD, significant stepwise increases were observed in levels of IL-1beta: 0.16+/-0.03, 0.22+/-0.06, and 0.41+/-0.08 pg/ml (p=0.035), and IL-10: 0.93+/-0.11, 1.17+/-0.14, and 2.94+/-0.65 pg/ml (p=0.008). A significant stepwise increase in levels of IL-1beta was also observed in eugonadal, borderline hypogonadal, and hypogonadal men: 0.19+/-0.05, 0.29+/-0.05, and 0.46+/-0.13 pg/ml (p=0.047). CONCLUSION: Consequently this data implicates IL-1beta and IL-10 in the pathogenesis of CAD and suggests that testosterone may regulate IL-1beta activity in men with CAD.

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Protocols for cryopreservation of sperm and oocytes would provide the ultimate control over parental crosses in selective breeding programmes. Sperm freezing is routine for many species, but oocyte freezing remains problematic, with virtually zero success in aquatic species to date. This paper describes the development of a successful protocol for cryopreserving high concentrations of Pacific oyster (Crassostrea gigas) oocytes. Ethylene glycol (10%) and dimethyl sulfoxide (15%) were found to be the most effective cryoprotectants resulting in post-thaw fertilization rates of 51.0+/-8.0 and 45.1+/-8.3%, respectively. Propylene glycol was less effective and methanol resulted in zero fertilization post-thaw. The use of Milli-Q water rather than seawater as a base medium significantly improved fertilization (20.4+/-3.0 and 8.7+/-2.2%, respectively) as did the inclusion of a 5 min isothermal hold at -10 or -12 degrees C (35.9+/-5.0 and 31.9+/-4.6%, respectively). The optimal cooling rate post-hold was 0.3 degrees C min(-1), with virtually zero post-thaw fertilization with cooling rates of 3 and 6 degrees C min(-1). Using an optimized protocol, post-thaw fertilization rates for oocytes from eight individual females ranged from 0.8 to 74.5% and D-larval yields from 0.1 to 30.1%. For three individuals, larvae were reared through to spat. Development of D-larvae to eyed larvae and spat was similar for larvae produced from unfrozen (24.8+/-4.1% developed to eyed larvae and 16.5+/-3.2% to spat) and cryopreserved (28.4+/-0.6 and 18.7+/-0.5%, respectively) oocytes. The ability to cryopreserve large quantities of oyster oocytes represents a major advance in cryobiology and selective breeding.

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BACKGROUND: Low serum testosterone is associated with several cardiovascular risk factors including dyslipidaemia, adverse clotting profiles, obesity, and insulin resistance. Testosterone has been reported to improve symptoms of angina and delay time to ischaemic threshold in unselected men with coronary disease. OBJECTIVE: This randomised single blind placebo controlled crossover study compared testosterone replacement therapy (Sustanon 100) with placebo in 10 men with ischaemic heart disease and hypogonadism. RESULTS: Baseline total testosterone and bioavailable testosterone were respectively 4.2 (0.5) nmol/l and 1.7 (0.4) nmol/l. After a month of testosterone, delta value analysis between testosterone and placebo phase showed that mean (SD) trough testosterone concentrations increased significantly by 4.8 (6.6) nmol/l (total testosterone) (p = 0.05) and 3.8 (4.5) nmol/l (bioavailable testosterone) (p = 0.025), time to 1 mm ST segment depression assessed by Bruce protocol exercise treadmill testing increased by 74 (54) seconds (p = 0.002), and mood scores assessed with validated questionnaires all improved. Compared with placebo, testosterone therapy was also associated with a significant reduction of total cholesterol and serum tumour necrosis factor alpha with delta values of -0.41 (0.54) mmol/l (p = 0.04) and -1.8 (2.4) pg/ml (p = 0.05) respectively. CONCLUSION: Testosterone replacement therapy in hypogonadal men delays time to ischaemia, improves mood, and is associated with potentially beneficial reductions of total cholesterol and serum tumour necrosis factor alpha.

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Several psychiatric diseases, including schizophrenia, are thought to have a developmental aetiology, but to date no clear link has been made between psychiatric disease and a specific developmental process. LPA(1) is a G(i)-coupled seven transmembrane receptor with high affinity for lysophosphatidic acid. Although LPA(1) is expressed in several peripheral tissues, in the nervous system it shows relatively restricted temporal expression to neuroepithelia during CNS development and to myelinating glia in the adult. We report the detailed neurological and behavioural analysis of mice homozygous for a targeted deletion at the lpa(1) locus. Our observations reveal a marked deficit in prepulse inhibition, widespread changes in the levels and turnover of the neurotransmitter 5-HT, a brain region-specific alteration in levels of amino acids, and a craniofacial dysmorphism in these mice. We suggest that the loss of LPA(1) receptor generates defects resembling those found in psychiatric disease.

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Inflammation plays a central pathogenic role in the initiation and progression of coronary atheroma and its clinical consequences. Cytokines are the mediators of cellular inflammation and promote local inflammation in the arterial wall, which may lead to vascular smooth muscle apoptosis, degradation of the fibrin cap and plaque rupture. Platelet adhesion and thrombus formation then occur, resulting clinically in unstable angina or myocardial infarction. Recent studies have suggested that cytokines are pathogenic, contributing directly to the disease process. 'Anti-cytokine' therapy may, therefore, be of benefit in preventing or slowing the progression of cardiovascular disease. Both oestrogens and testosterone have been shown to have immune-modulating effects; testosterone in particular appears to suppress activation of pro-inflammatory cytokines. Men with low testosterone levels are at increased risk of coronary artery disease. An anti-inflammatory effect of normal physiological levels of sex hormones may, therefore, be important in atheroprotection. In this Article, we discuss some of the mechanisms involved in atherosclerotic coronary artery disease and the putative link between testosterone deficiency and atheroma formation. We present the hypothesis that the immune-modulating properties of testosterone may be important in inhibiting atheroma formation and progression to acute coronary syndrome.

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