Microbial contamination of open-but-unused portions of wound dressings stored in home settings.

The purpose of this study was to investigate incidence rates and levels of microbial contamination in open-but-unused portions of wound dressings stored in home settings. Portions of wound dressings were collected at up to four home visits for 104 clients undertaking wound management within their home. A control sample and stored sample was collected on each home visit and sent for pathology testing to identify levels of microbial contamination.

Identification of medium/high-threshold extrinsic mechanosensitive afferent nerves to the gastrointestinal tract.

Background & Aims: Large distentions reliably evoke sensation from the noninflamed, nonischemic bowel, but the specialized afferent axonal structures responsible have not been morphologically identified. We investigated whether their transduction sites are located on major blood vessels close to and within the gut wall.

Methods: In vitro extracellular recordings were made from mesenteric nerve trunks in guinea pig ileum, combined with rapid axonal dye filling and immunohistochemical analysis of nerve trunks.

Mechanisms of mechanotransduction by specialized low-threshold mechanoreceptors in the guinea pig rectum.

The guinea pig rectum, but not the colon, is innervated by a specialized class of distension-sensitive mechanoreceptors that have transduction sites corresponding to rectal intraganglionic laminar endings (rIGLEs). Rectal mechanoreceptors recorded in vitro had low threshold to circumferential stretch, adapted slowly, and could respond within 2 ms to mechanical stimulation by a piezo-electric probe. Antagonists to ionotropic N-methyl-D-aspartate (NMDA; CGS 19755, memantine) and non-NMDA (6,7-dinitroquinoxaline-2,3-dione) glutamate receptors did not affect mechanotransduction.

Mechanical activation of rectal intraganglionic laminar endings in the guinea pig distal gut.

The rectum receives specialized extrinsic afferent innervation by stretch-sensitive, low threshold, slowly adapting mechanoreceptors, with transduction sites shown to correspond to rectal intraganglionic laminar endings (IGLEs). Rectal IGLEs are located in myenteric ganglia, surrounded by the longitudinal and circular smooth muscle layers; in this study we investigated the mechanical stimuli to which they respond. Mechanoreceptors had graded responses to highly focal transmural compression with von Frey hairs.

Rectal intraganglionic laminar endings are transduction sites of extrinsic mechanoreceptors in the guinea pig rectum.

Background & Aims: Vagal afferent mechanoreceptors in the upper gut have recently been identified morphologically as intraganglionic laminar endings (IGLEs), but little is known about the structure of mechanoreceptive endings elsewhere in the gastrointestinal tract. We have morphologically characterized the nerve endings of specialized mechanoreceptors in the rectum.

Methods: Extracellular recordings from guinea pig rectal and colonic nerves were made, in vitro, in combination with rapid anterograde transport of biotinamide, to reveal the morphology of recorded fibers.

Excitation of rat colonic afferent fibres by 5-HT(3) receptors.

The gastrointestinal tract contains most of the body's 5-hydroxytryptamine (5-HT) and releases large amounts after meals or exposure to toxins. Increased 5-HT release occurs in patients with irritable bowel syndrome (IBS) and their peak plasma 5-HT levels correlate with pain episodes. 5-HT(3) receptor antagonists reduce symptoms of IBS clinically, but their site of action is unclear and the potential for other therapeutic targets is unexplored.