MAGNETIC RESONANCE IMAGING FINDINGS OF EQUINE SOLAR PENETRATION WOUNDS

The magnetic resonance (MR) imaging features, signalment, clinical history and outcome of 55 horses with a penetrating sole injury were evaluated. Our aim was to describe MR imaging findings within the hoof capsule, assess the utility of the technique and give recommendations for the optimal MR imaging protocol to evaluate such injuries. Data from five equine hospitals were analyzed retrospectively. The tract was more likely to be visualized in animals scanned within the first week postinjury. There was no significant predisposition based on breed, age, or gender. T2*W transverse sequences were the most useful for assessment of solar penetrations due to their orientation perpendicular to the deep digital flexor tendon, the reduced scanning time, and the T2* capability of enhancing magnetic susceptibility caused by hemorrhage.     

External Fixator Clamp Reuse Degrades Clamp Mechanical Performance

Objective— To determine the effects of clamp reuse for the Kirschner–Ehmer (KE); Securos; and the IMEX–SK clamp.
Study Design— Experimental bench test of mechanical properties.
Methods— Specially designed fixtures were used to mechanically test 18 clamps of each type with respect to 6 mechanical variables: fixator pin slippage, connecting bar slippage, fixator pin rotation, connecting bar rotation, and clockwise and counterclockwise clamp–bolt axis pivot. Each clamp was tested 6 times for each variable at 7.68 Nm of clamp–bolt tightening torque. Results were compared using repeated measures ANOVA.
Results— For the IMEX–SK clamp, a significant degradation in the force required to cause slippage was found for connecting bar slippage and fixator pin rotation; however, this clamp also had a significant increase in the force to initiate slippage for clockwise clamp–bolt axis pivot with reuse. The Securos clamp had significant degradation in connecting bar slippage, connecting bar rotation, and fixator pin rotation whereas the KE clamp had significant degradation in connecting bar slippage only.
Conclusions— All 3 external fixator clamp types degraded in 1 or more movement variables in their ability to resist motion with reuse. The IMEX and Securos clamps were more subject to degradation than the KE clamp and this may have clinical importance for fixator composite rigidity.
Clinical Relevance— Fracture-reduction stability is related to the ability to resist motion within a clamp. The unpredictable nature of degradation we found cautions against repeated use. Clinicians should consider reuse of external fixator clamps with the knowledge that repeated use degrades clamp mechanical performance.     

WEEDS OF TOMATO AND CORN FIELDS IN TWO REGIONS OF ONTARIO

Summary. Amaranthus retroflexus, Chenopodium album, Ambrosia artemisiifolia, Setaria glauca, S. viridis and Echinochloa crusgalli were the most widespread and abundant of the 103 weed species found in eighty-eight fields of tomatoes ( Lycopersicon esculentum ) and sweet corn ( Zea mays ) surveyed in Prince Edward County and in Essex and Kent Counties during 1960 and 1961. None of the important weeds in either crop occurred exclusively in that crop. Differences in weed floras were greater between regions than between crops. Abutilon theophrasti, Euphorbia maculata, Apocynum cannabinum var. suksdorfii and Physalis virginiana var. subglabrata , important weeds in both crops in Essex and Kent, were not found in any surveyed field in Prince Edward County. Average numbers of weed species per field were 15.7 in Prince Edward County and 12.9 in Essex and Kent. Small dense infestations of Fumaria officinalis and Salvia reflexa , rare weeds in Canada, were discovered in Prince Edward County.
Mauvaises herbes des cultures de tomates et du maïs dans deux régions de l'Ontario     

Possible peroxidase functions in the interaction between the parasitic plant, Orobanche aegyptiaca, and its host, Arabidopsis thaliana

The mechanism by which the flowering holoparasitic plant, Orobanche aegyptiaca , infects its host without evoking a defence mechanism is still poorly understood. In this work, we studied several mechanisms used by phytopathogenic fungi. We focussed on the possible role of peroxidases during O. aegyptiaca penetration into the roots of Arabidopsis thaliana . A convenient experimental system for studying the interaction under sterile conditions was developed. The formation of extracellular reactive oxygen species (ROS) was detected at the interaction site before, during, and after the parasite penetrated into the host. These extracellular ROS probably originated from the parasite. However, no intracellular ROS could be detected at the site of the interaction. Peroxidase activity was observed mainly at the apex of the root of the parasite and in the adventitious roots of the tubercle. Benzhydroxamic acid, a peroxidase inhibitor, was used to probe the possible role of peroxidase in the infection process. Peroxidase activity was observed in the root apex and adventitious roots of O. aegyptiaca, but no evidence was found for its participation in the actual infection process. Peroxidase activity was also found in the later stages of the interaction between the host and the parasite. We propose that peroxidases could have a role in generating extracellular ROS for loosening the cell wall of the host in order to facilitate penetration. Alternatively, the ROS could act in facilitating the root elongation of the parasite.     

Population dynamics of the exploited sea cucumber Isostichopus fuscus in the western Galápagos Islands, Ecuador

Long-term density data for the sea cucumber, Isostichopus fuscus, from Canal Bolivar (separating western Isabela and eastern Fernandina Islands), Galápagos, were compared with catch statistics and used in a stock depletion model to determine the extent of the effects of the fishery on the existing population and the potential for the population to recover after each fishing season. Recruitment indices were found to be low from 1994 until mid-1999, when a mass recruitment event was registered and numbers of small individuals increased dramatically. The increase in density of juveniles peaked in 2001 and has declined since. Recruitment in this species of sea cucumber appears to be highly sporadic and may depend on intense climatic events such as the warm El Niño. Current levels of fishing activity are unsustainable. The management implications of pulse recruitment in this fishery are discussed.     

64‐MULTIDETECTOR COMPUTED TOMOGRAPHIC ANGIOGRAPHY OF THE CANINE CORONARY ARTERIES

Canine coronary artery angiography (CTA) was performed in four anesthetized healthy dogs using 64‐multidetector computed tomography. Esmolol, a β‐1 adrenergic receptor antagonist, and sodium nitroprusside, an arteriolar and venous dilator, were administered to enhance visualization of the coronary arteries by reducing heart rate and creating vasodilation. The left main coronary artery with its three main branches and the right coronary artery were visualized and subdivided in 13 segments for evaluation. Optimal reconstruction interval, expressed as percentage of the R‐to‐R interval, was determined at 5% in 2.9%, 35% in 1%, 75% in 21.2%, 85% in 43.3%, and 95% in 31.7% of the segments. Overall image quality was good in 41.3% of the segments and excellent in 14.4%. There was blur in 98.1%, motion in 17.3%, and stair step in 6.7% of the evaluated segments, but these artifacts did not interfere with anatomic depiction of the arteries. Cross‐sectional anatomy of the coronary arteries as evaluated from the coronary CTA agreed well with gross anatomic evaluation and published information. The use of esmolol did not lead to the target heart rate of 60–65 beats/min. Nitroprusside had no significant effect on visualized length or diameter of the coronary artery branches. Coronary CTA is useful for the anatomic depiction of coronary artery branches in the dog.     

Traumatic Temporal Lobe Syndrome in the Dog with Atypical Encephalitis

Abstract—The clinical, electrophysiological and histological findings in a young dog showing unusual neurological symptoms are reported. EEG recordings showed slow wave activity predominantly over the right side of the brain, while in the left fore and hind limbs constant myoclonic twitches were observed. Exploratory craniotomy disclosed no gross anomaly, but surface electrodes revealed the slow wave activity to be localized in the right temporal region. Histologic examination showed that there was a severe traumatic lesion on the right temporal lobe, accompanied by neuronal degeneration. Bacteria were found throughout the CNS and on culture were identified as Streptococcus faecalis. Résuxné—Les découvertes cliniques, électrophysiologiques et histologiques chez un jenue chien indiquant des symptǒmes neurologiques peu usuels y sont décrites. Des enregistrements EEG ont indiqué une lente activité d'onde surtout manifeste du cǒté droit du cerveau tan& que des mouve-ments convulsifs myocliniques constants se sont vérifiés sur les membres avant et arrière gauches. Une étude craniotomique n'a révélé aucune anomalie générale, mais des électrodes en surface ont indiqué que l'activité lente d'onde était localisée dans la région temporale droite. L'examen histo-logique a révélé qu'il y avait une léion traumatique sévère sur le lobe temporal de droite, accom-pagnée d'une dégénération de cellules nerveuses. L'existence de bactéries a été vérifiée à travers la CNS et mises en culture elks ont été identifiées comme étant Streptococcus faecalir. Zusammedassung—Die klinischen, elektrophysiologischen und histologischen Beobachtungen en einem jungen Hunde mit ungewöhnlichen neurologischen Symptomen werden berichtet. EEG Aufzeichnungen zeigten langsame Wellenaktivität, in der Hauptsache über der rechten Gehirnseite, während im linken Vorder- und Hinterbein konstante myoklonische Zuckungen beobachtet wurden. Diagnostische Craniotomie ergab keine wesentliche Anomalie, aber Oberflächen-elektroden zeigten an, dass die langsame Wellenaktivität in der rechten Temporalgegend lokalisiert war. Histologkche Untersuchung ergab eine schwere traumatische Veränderung des rechten Lobus temporalis mit Neuron Degeneration. Bakterien wurden im ganzen Zentralnervensystem gefunden. Deren Kultur ergab Streptococcus faecalis.     

PULMONARY ANGIOGRAPHY WITH 64‐MULTIDETECTOR‐ROW COMPUTED TOMOGRAPHY IN NORMAL DOGS

Pulmonary angiography using 64‐multidetector‐row computed tomography (MDCT) was used to evaluate pulmonary artery anatomy, and determine the sensitivity of pulmonary artery segment visualization in four Beagle dogs using images reconstructed to 0.625 mm and retro‐reconstructed to 1.25 and 2.5 mm slice thickness. Morphologically, characteristic features included a focal narrowing in the right cranial pulmonary artery in all dogs, which should not be mistaken as stenosis. While the right cranial pulmonary artery divided into two equally sized branches that were tracked into the periphery of the lung lobe in all dogs, only a single left cranial (cranial portion) lobar artery was present. Compared with 1.25 and 2.5 mm retro‐reconstructions, 0.625 mm reconstructions allowed for detection of significantly (P≤0.05) more pulmonary artery segments and sharper depiction of vessel margins. Clinical applications such as prevalence and significance of diameter changes, and detection of pulmonary arterial thrombembolism on lobar and sublobar level, using pulmonary angiography with 64‐MDCT applying 0.625 mm reconstruction slice thickness remain to be established.     

I&Q系统对颈部鳞状上皮细胞癌治疗作用的监测

目的:近红外光光谱技术监测颈部鳞状细胞癌肿的治疗作用.方法:应用I&Q(同步或正交相位)检测系统来跟踪监测颈部癌肿病人的血氧含量.结果:现今临床采用的放疗和化疗方法都能改变肿瘤组织内血和氧含量,结论:I&Q系统则可以定量地检测组织的生物特性的变化.     

The Bowmont Norway Spruce Sample Plots 1930-60

The sixteen one-chain-square plots replicated four times werelaid out in the form of a latin square in 1930 in a denselystocked 20-year-old plantation with just over 3,000 stems peracre to study the effect of four thinning grades. Following up Hummel's 1947 paper (Forestry 21, 30), the authorgives figures for stems per acre, height, girth increment, basalarea, volume, and crown measurements up to 1960.