Measurement of the Lateral Thoracic Reflex Latency in Ponies

Lateral thoracic nerve reflex latencies values were measured in ponies using a simple, non-invasive technique. The reflex was elicited using an external triggering hammer attached to an electrodiagnostic unit. The resulting evoked, compound muscle action potentials were recorded with electrodes, which were placed over the 6th ribs or 11th rib level with the axilla. Two superimposed repeats of 4 signal-averaged sweeps of 50 or 100 milliseconds were recorded and the estimated reflex pathway was measured for each subject in order to calculate the reflex latencies and latency velocities. Mean left and right 6th rib peak latencies were not significantly different from each other ( P = .609), but left 6th rib latencies were shorter than those recorded from the 11th rib ( P < .0001), substantiating the existence of an indirect (central) pathway to the reflex. The calculated left and right 6th rib latency velocities were not significantly different from each other ( P = .58) but left 6th rib latency velocities were different from left 11th rib ( P = .009). The calculated latency velocities were within the broad range for corticospinal tract motor conduction velocities and comparable to magnetic motor evoked latency velocities. The use of lateral thoracic reflex latency measurements to objectively identify the site of spinal cord lesions is discussed.     

Soil carbon distribution and quality in a montane rangeland-forest mosaic in northern Utah

Relatively little is known about soil organic carbon (SOC) dynamics in montane ecosystems of the semi-arid western U.S. or the stability of current SOC pools under future climate change scenarios. We measured the distribution and quality of SOC in a mosaic of rangeland-forest vegetation types that occurs under similar climatic conditions on non-calcareous soils at Utah State University's T.W. Daniel Experimental Forest in northern Utah: the forest types were aspen [Populus tremuloides] and conifer (mixture of fir [Abies lasiocarpa] and spruce [Picea engelmannii]); the rangeland types were sagebrush steppe [Artemisia tridentata], grass-forb meadow, and a meadow-conifer ecotone. Total SOC was calculated from OC concentrations, estimates of bulk density by texture and rock-free soil volume in five pedons. The SOC quality was expressed in terms of leaching potential and decomposability. Amount and aromaticity of water-soluble organic carbon (DOC) was determined by water extraction and specific ultra violet absorbance at 254 nm (SUVA) of leached DOC. Decomposability of SOC and DOC was derived from laboratory incubation of soil samples and water extracts, respectively.

Although there was little difference in total SOC between soils sampled under different vegetation types, vertical distribution, and quality of SOC appeared to be influenced by vegetation. Forest soils had a distinct O horizon and higher SOC concentration in near-surface mineral horizons that declined sharply with depth. Rangeland soils lacked O horizons and SOC concentration declined more gradually. Quality of SOC under rangelands was more uniform with depth and SOC was less soluble and less decomposable (i.e., more stable) than under forests. However, DOC in grass-forb meadow soils was less aromatic and more bioavailable, likely promoting C retention through cycling. The SOC in forest soils was notably more leachable and decomposable, especially near the soil surface, with stability increasing with soil depth. Across the entire dataset, there was a weak inverse relationship between the decomposability and the aromaticity of DOC. Our data indicate that despite similar SOC pools, vegetation type may affect SOC retention capacity under future climate projections by influencing potential SOC losses via leaching and decomposition.     

International Harmonization of Nomenclature and Diagnostic Criteria (INHAND) progress to date and future plans

The INHAND Proposal (International Harmonization of Nomenclature and Diagnostic Criteria for Lesions in Rats and Mice) has been operational since 2005. A Global Editorial Steering Committee (GESC) manages the overall objectives of the project and the development of harmonized terminology for each organ system is the responsibility of the Organ Working Groups (OWG), drawing upon experts from North America, Europe and Japan.Great progress has been made with 9 systems published to date – Respiratory, Hepatobiliary, Urinary, Central/Peripheral Nervous Systems, Male Reproductive and Mammary, Zymbals, Clitoral and Preputial Glands in Toxicologic Pathology and the Integument and Soft Tissue and Female Reproductive System in the Journal of Toxicologic Pathology as supplements and on a web site – www.goreni.org. INHAND nomenclature guides offer diagnostic criteria and guidelines for recording lesions observed in rodent toxicity and carcinogenicity studies. The guides provide representative photo-micrographs of morphologic changes, information regarding pathogenesis, and key references. During 2012, INHAND GESC representatives attended meetings with representatives of the FDA Center for Drug Evaluation and Research (CDER), Clinical Data Interchange Standards Consortium (CDISC), and the National Cancer Institute (NCI) Enterprise Vocabulary Services (EVS) to begin incorporation of INHAND terminology as preferred terminology for SEND (Standard for Exchange of Nonclinical Data) submissions to the FDA. The interest in utilizing the INHAND nomenclature, based on input from industry and government toxicologists as well as information technology specialists, suggests that there will be wide acceptance of this nomenclature. The purpose of this publication is to provide an update on the progress of INHAND.     

Can Batesian mimicry help plants to deter herbivores?

Several authors have suggested that edible plants could avoid herbivory by mimicking olfactory cues of toxic plants. However, very few studies have been carried out to test this hypothesis. The aims of the present study were to identify the volatiles of three clover species and to test whether a species lacking chemical defences, such as red clover, could avoid being grazed by rabbits by mimicking the volatiles of the cyanogenic white clover. Two main volatiles were identified in all three clover species, and a further two volatiles were present in white clover only. Rabbits presented with a choice between white clover, red clover and red clover sprayed with white clover extract ate significantly more red clover than white or white-flavoured red clover. The results suggest that the volatiles of toxic plants could be used and exploited as a source of natural, safe and effective repellents to control the impact of pest herbivores on plants.     

Crown allometry and growing space requirements of four rare domestic tree species compared to oak and beech: implications for adaptive forest management

European Journal of Forest Research - Rare domestic tree species are increasingly being viewed as promising alternatives and additions to current main tree species in forests facing climate change....     

Gamna‐Gandy bodies: a case of mistaken identity in the spleen of a cat

A 4‐year‐old, female spayed Domestic Shorthair cat was presented for a 2‐day history of lethargy, anorexia, and vomiting. Diagnostic assessments revealed a severe, regenerative anemia and the presence of a solitary, 3 × 4 cm splenic mass. Cytologic examination of fine‐needle aspirates of the splenic mass showed sheets of pleomorphic histiocytic cells with numerous intracellular and extracellular, negatively staining to deeply basophilic, branching structures. These structures were typically of thin uniform thickness with random angled branching that formed geometrical shapes and fragments, occasionally with sharpened ends and a crystalline appearance. Septal‐like divisions were irregularly spaced along some of the linear branches. The cytology was interpreted as a probable histiocytic inflammatory response to the unidentified foreign material with histiocytic sarcoma as a differential diagnosis. Histopathologic evaluation of the splenic mass resulted in a diagnosis of histiocytic sarcoma. The branching material stained positively for both iron and calcium, indicating that the material was compatible with Gamna‐Gandy bodies present secondary to tumor‐associated hemorrhage and the formation of calcium–iron complexes.     

Expression of retinoid receptors in lungs of cattle,dogs, and pigs

Retinoids play an important role in lung development and immune response. The effects of retinoids are mediated through 2 families of retinoid receptors: retinoic acid receptors (RARs) and retinoid X receptors (RXRs), with alpha (α), beta (β), and gamma (γ) subtypes in each family. To date, no data exist on the expression pattern of retinoid receptors in lungs of cattle, dogs, and pigs. Because of the biomedical importance of retinoid receptors in inflammation and immune responses, Western blot, immunohistology, and immunoelectron microscopy were used to determine the expression of retinoid receptors in normal lungs of cattle, dogs, and pigs (n = 2 for each species). Western blot showed expression of all 6 retinoid receptor subtypes in pig lungs. Immunohistology data indicated differential expression of retinoid receptors in airway epithelium, vascular endothelium, alveolar/septal macrophages, and alveolar septum in all 3 species. Electron microscopy showed nuclear localization of retinoid receptors in neutrophils and pulmonary intravascular macrophages. Retinoic acid receptors (RAR) α subtype were localized in cytoplasmic vacuoles of pig monocytes. These data indicate constitutive expression of retinoid receptors in the lungs of cattle, dogs, and pigs.     

Effect of aluminum uptake on growth and enzyme activity in Pisum sativum var. ‘Alaska’ and ‘Little Marvel’

It is usually assumed that plant tissue responses to nutritional elements are due to specific genetic differences that may exist either between inbred or closely related species. Little Marvel (dwarf) and Alaska (normal) varieties of 14‐day old pea seedlings were treated with four different concentrations of Al‐containing nutrient solution (0.0mM, 0.2mM, 0.6mM and distilled H₂O), prior to being exposed for 14 days to either DARK, LIGHT, or UV. Selected tissues (root tip, main root, main stem and proximal stem) were bioassayed for peroxidase and polyphenol oxidase enzyme activities, fresh wt vs. dry wt, water uptake and stem growth. The present study suggests that Little Marvel and Alaska pea tissue responds to high toxicity levels of Al by demonstrating an enhancement of enzymic activity. Tissue weight, growth and water uptake also show differential tissue specificity in both Little Marvel and Alaska tissue, in terms of Al toxicity response, given a particular external exposure.