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Rapid decline of crayfish in European freshwaters and continuing threat necessitate integrated actions in conservation and management of native crayfish populations. Besides biological reasons (diseases, plague), the impact of toxic and harmful substances (fertilisers, herbicides) or wastewater effluents, habitat alteration or fragmentation have been responsible for their decline in some regions. The same is true for the region of South Tyrol, where compared to previous investigations, only 10 of a former total of 15 crayfish locations in the water bodies could be affirmed. Although two new populations of the non-indigenous Astacus astacus were detected, the native Austropotamobius pallipes continues to decline. While many investigations have focused accurately on causal coherences for the decline of native populations, the properties of crayfish facilitate to reverse the situation. In a few examples, the potential of Austropotamobius pallipes, the native crayfish in South Tyrol, as “surrogate species” for effective biological conservation is discussed. Given the various adequate attributes of freshwater crayfish as surrogate species (including indicator species, umbrella species and flagship species qualities), they may help to advance not only the crayfish situation itself but also freshwater ecosystem properties in general.

Aim: After spinal cord injuries (SCIs), patients may develop either detrusor-sphincter dyssynergia (DSD) or urinary incontinence, depending on the level of the spinal injury. DSD and incontinence reflect the loss of coordinated neural control among the detrusor muscle, which increases bladder pressure to facilitate urination, and urethral sphincters and pelvic floor muscles, which control the bladder outlet to restrict or permit bladder emptying. Transcutaneous magnetic stimulation (TMS) applied to the spinal cord after SCI reduced DSD and incontinence. We defined, within a mathematical model, the minimum neuronal elements necessary to replicate neurogenic dysfunction of the bladder after a SCI and incorporated into this model the minimum additional neurophysiological features sufficient to replicate the improvements in bladder function associated with lumbar TMS of the spine in patients with SCI. Methods: We created a computational model of the neural circuit of micturition based on Hodgkin-Huxley equations that replicated normal bladder function. We added interneurons and increased network complexity to reproduce dysfunctional micturition after SCI, and we increased the density and complexity of interactions of both inhibitory and excitatory lumbar spinal interneurons responsive to TMS to provide a more diverse set of spinal responses to intrinsic and extrinsic activation of spinal interneurons that remains after SCI. Results: The model reproduced the re-emergence of a spinal voiding reflex after SCI. When we investigated the effect of monophasic and biphasic TMS at two frequencies applied at or below T10, the model replicated the improved coordination between detrusor and external urethral sphincter activity that has been observed clinically: low-frequency TMS (1 Hz) within the model normalized control of voiding after SCI, whereas high-frequency TMS (30 Hz) enhanced urine storage. Conclusion: Neuroplasticity and increased complexity of interactions among lumbar interneurons, beyond what is necessary to simulate normal bladder function, must be present in order to replicate the effects of SCI on control of micturition, and both neuronal and network modifications of lumbar interneurons are essential to understand the mechanisms whereby TMS reduced bladder dysfunction after SCI. Author summary: We developed a computer model using Hodgkin-Huxley representations of spinal interneurons to simulate normal bladder control, dysfunctional control of micturition after SCI, and clinically observed bladder responses to transcutaneous magnetic stimulation (TMS) of the lumbar spine. We incorporated an infantile spinal voiding reflex by adding lumbar interneurons to make a spinal voiding reflex possible and modified descending control of these neurons to inhibit the infantile reflex in normal adults. After SCI, the descending inhibition of the spinal voiding reflex is lost, and the spinal voiding reflex re-emerges. To make the lumbar spine response to TMS, it was necessary to add two excitatory interneurons and one inhibitory neuron in the lumbar spine: these neurons manifested frequency-specific responses to TMS. Based on the dynamical properties of the inhibitory and excitatory neurons responding to TMS, low frequency TMS (1 Hz) permitted the action of the re-emergent spinal voiding reflex to coordinate bladder contraction and urethral relaxation so that effective bladder emptying was re-established during TMS. Higher frequency TMS contracted the urethral sphincter and prevented simulated leaking and incontinence. Greater lumbar interneuronal complexity, consistent with animal experiments, is required to simulate bladder responses to SCI and TMS. [ABSTRACT FROM AUTHOR]

Background: In the spectrum of surgical decision-making, wound closure material is often an afterthought. However, the findings of a recent meta-analysis suggest that the rate of surgical site infections (SSIs) is increased by using staples to close surgic

Background: A recently published meta-analysis comparing metallic staples to sutures in orthopaedic procedures revealed three fold increase in risk for infection in stapled wounds. The studies included in the meta-analysis are at risk of bias due to experi

In testing the hypothesis that interleukin-4 receptor [alpha]-subunit (IL-4R [alpha])-coupled signaling mediates altered airway smooth muscle (ASM) responsiveness in the atopic sensitized state, isolated rabbit tracheal ASM segments were passively sensitized with immunoglobulin E (IgE) immune complexes, both in the absence and presence of an IL-4R[alpha] blocking antibody (anti-IL-4R[alpha]Ab). Relative to control ASM, IgE-sensitized tissues exhibited enhanced isometric constrictor responses to administered ACh and attenuated relaxation responses to isoproterenol. These proasthmatic-like effects were prevented in IgE-sensitized ASM that were pretreated with anti-IL-4R[alpha]Ab. In complementary experiments, IgE-sensitized cultured human ASM cells exhibited upregulated expression of IL-13 mRNA and protein, whereas IL-4 expression was undetected. Moreover, extended studies demonstrated that 1) exogenous IL-13 administration to naive ASM elicited augmented contractility to ACh and impaired relaxation to isoproterenol, 2) these effects of IL-13 were prevented by pretreating the tissues with an IL-5 receptor blocking antibody, and 3) IL-13 administration induced upregulated mRNA expression and release of IL-5 protein from cultured ASM cells. Collectively, these findings provide new evidence demonstrating that the altered responsiveness of IgE-sensitized ASM is largely attributed to activation of an intrinsic Th2-type autocrine mechanism involving IL-13/IL-4R[alpha]-coupled release and action of IL-5 in the sensitized ASM itself. Th2 cytokines; immunoglobulin E; atopy; asthma; interleukin-13

Goldstein, Jonathan I., James M. Mok, Christopher M. Simon, and J. C. Leiter. Intracellular pH regulation in neurons from chemosensitive and nonchemosensitive regions of Helix aspersa. Am J Physiol Regulatory Integrative Comp Physiol 279: R414-R423, 2000.--We used 2',7'-bis(carboxyethyl)-5(6)-carboxyflourescein (BCECF), a pH-sensitive fluorescent dye, to study intracellular pH ([pH.sub.i]) regulation in neurons in [CO.sub.2] chemoreceptor and nonchemoreceptor regions in the pulmonate, terrestrial snail, Helix aspersa. We studied [pH.sub.i] during hypercapnic acidosis, after ammonia prepulse, and during isohydric hypercapnia. In all treatment conditions, [pH.sub.i] fell to similar levels in chemoreceptor and nonchemoreceptor regions. However, [pH.sub.i] recovery was consistently slower in chemoreceptor regions compared with nonchemoreceptor regions, and [pH.sub.i] recovery was slower in all regions when extracellular pH ([pH.sub.e]) was also reduced. We also studied the effect of amiloride and DIDS on [pH.sub.i] regulation during isohydric hypercapnia. An amiloride-sensitive mechanism was the dominant [pH.sub.i] regulatory process during acidosis. We conclude that [pH.sub.e] modulates and slows [pH.sub.i] regulation in chemoreceptor regions to a greater extent than in nonchemoreceptor regions by inhibiting an amiloride-sensitive [Na.sup.+]/[H.sup.+] exchanger. Although the phylogenetic distance between vertebrates and invertebrates is large, similar results have been reported in [CO.sub.2]-sensitive regions within the rat brain stem. respiratory control; acid-base balance; central carbon dioxide chemoreceptors; invertebrates; snails

Purpose: Central vein point-of-care ultrasonography must be reproducible to detect intravascular volume changes. We sought to determine which measurement step, image acquisition or interpretation, could be more compromising for reproducibility.Methods: Three investigators each acquired inferior vena cava (IVC) and internal jugular (IJV) vein ultrasonographic sequences (US) from a convenience sample of 21 hospitalized general medicine participants and then interpreted each US three separate times. We partitioned the random errors of acquisition and interpretation, attributing wider dispersions of each to larger reductions in reproducibility.Results: We analyzed 351 interpretations of 39 IVC and 432 interpretations of 48 IJV US. Reproducibility of the maximum (standard error of measurement 3.3 mm [95% confidence interval, CI 2.7-4.2 mm]) and minimum (4.8 mm [3.9-6.3 mm]) IVC diameter measurements were worse than that of the mediolateral (2.5 mm [2.0-3.2 mm]) and anteroposterior (2.5 mm [2.0-3.1 mm]) IJV diameters. The dispersions of random measurement errors were wider among acquisitions than interpretations.Conclusions: Among our investigators, central vein diameter measurements obtained by point-of-care ultrasonography are not sufficiently reproducible to distinguish clinically meaningful intravascular volume changes from measurement errors. Reproducibility could be most effectively improved by reducing the random measurement errors of acquisition. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 45:488-496, 2017. [ABSTRACT FROM AUTHOR]