Preliminary Investigation of the Area Under the l‐Lactate Concentration–Time Curve (LACAREA) in Critically Ill Equine Neonates

Background

A variety of measures of l‐lactate concentration ([LAC]) in the blood of critically ill neonatal foals have shown utility as prognostic indicators. These measures, evaluating either the severity of hyperlactatemia or the duration of exposure to hyperlactatemia, perform fairly well and have correctly classified 75–80% of foals examined in several studies. The area under the l‐lactate concentration versus time curve (LAC _Area) encompasses both severity and duration of hyperlactatemia and should improve correct classification of patient survival.

Hypothesis/Objectives

LAC _Area is larger in nonsurviving critically ill neonatal foals.

Animals

Forty‐nine foals admitted for critical illness to 1 of 4 referral hospitals.

Methods

Whole blood was obtained at admission and 6, 12, 18, and 24 hours after admission for measurement of l‐lactate using a handheld lactate meter. LAC _Area was calculated for: admission–6, 6–12, 12–18, 18–24 hours, and admission–24 hours using the trapezoidal method and summing the 6‐hours interval areas to determine total 24 hours area. Differences between survivors and nonsurvivors were determined using robust regression and Kruskal–Wallis testing, P < .05.

Results

LAC _Area was significantly larger in nonsurviving foals (n = 9) than in surviving foals (n = 40) at all time periods examined.

Conclusions and Clinical Importance

Differences in LAC _Area between surviving and nonsurviving critically ill neonatal foals are large and support further investigation of this method as an improved biomarker for survival in critically ill neonatal foals is indicated.     

The nomenclature of cell wall deformations

Summary The nomenclature of cell wall deformations has been subject to confusion since first described in the early 1900's. The reasons for this confusion are discussed and a history of the nomenclatural changes presented. A revision of the nomenclature is suggested which takes account of recent observations made using the scanning electron microscope.     

Inheritance of resistance to Puccinia coronata Corda and Rhynchosporium orthosporum Caldwell in Italian ryegrass

Summary Progeny analysis within Italian ryegrass (Lolium multiflorum) cv. RvP infected with a single clone of crown rust (Puccinia coronata f. sp. lolii) revealed major factors, one probably a single dominant gene, conferring resistance in two of twelve randomly selected parents. The remaining variation in resistance to this pathogen, and all of the variation in resistance to Rhynchosporium orthosporum, was controlled by a relatively large number of minor genes exhibiting neither dominance nor epistasis. There was no significant maternal inheritance. Absence of any correlation between progeny scores for reaction to the two pathogens indicated that resistance to each was inherited independently.     

Genetic improvement of yield of nitrogen of Lolium perenne pastures

Summary Four varieties of Lolium perenne with similar flowering dates bred over a 30 year period were grown in an orthogonal plot trial with two contrasting harvesting frequencies and three levels of fertiliser (0.2, 0.4 and 0.6 t/ha of N annually). In the second harvest year, the nitrogen (N) content of herbage at each harvest was determined and the yields of N calculated. The newest variety (Ba 10761) gave a 20% higher mean annual yield of N than the oldest (S.321). The influence of variety in increasing the ratio of N recovered: N applied was as great or greater than the influence of harvesting frequency or level of applied N. There were small differences between varieties in N content (%N), N content being inversely related to N yield.     

Useful variation in in vitro digestibility within perennial ryegrass

In vitro dry matter digestibility (DMD) and dry matter yield (DMY) of herbage from plots sown with three selected perennial ryegrass varieties with similar heading dates (Ba11778, Talbot and Gator) under a range of harvesting frequencies (2, 3, 4 and 5-weekly harvests) were compared over two harvest years (1994 and 1995). Varieties varied in mean percentage DMD over all harvests and harvesting frequencies by 3.4 and 3.5 units in 1994 and 1995 respectively. Varietal ranking in mean DMD over all harvests was the same under each harvesting frequency in both years: Ba11778 being the highest, Gator the lowest and Talbot intermediate. In 1995, Gator had a higher proportion of unsown species in the herbage than both Ba11778 and Talbot but this was only a minor factor contributing to the differences among the varieties in mean DMD over all harvests. Although varieties consistently ranked in the same order of mean DMD over all harvesting frequencies during 13 5-week periods, the range among varieties varied from less than 1 unit to 8.6 units. This range was greatest in mid-season of each year when mean DMD over all varieties was lowest. The minimum mean DMD over all harvesting frequencies during both years was 75.5%, 70.9% and 66.8% for Ba11778, Talbot and Gator respectively. The most digestible variety Ba11778 also had higher annual DMY than the other two varieties in both harvest years and under all four harvesting frequencies. These results indicate that there is sufficient useful genetic variation for DMD within perennial ryegrass to justify breeding for the trait and its routine assessment in official variety trials.     

Pteroside A2--a new illudane-type sesquiterpene glucoside from pteridium caudatum L. Maxon,and the spectrometric characterization of caudatodienone

Fractionation of an extract of Pteridium caudatum L. Maxon. (syn P. aquilinum L. Kuhn var. caudatum) which had earlier yielded the illudane-type sesquiterpene glucosides, ptaquiloside (1a), isoptaquiloside (1b), and caudatoside (1c) afforded a mixture containing 1a and two minor components. Preparative HPLC afforded ptaquiloside Z (1d) and a new pteroside glucoside (pteroside A2) (3e), which was identified using a combination of mass spectral and one- and two-dimensional NMR analyses. The (1)H and (13)C NMR and mass spectrometric characterization of caudatodienone (2b), an unstable dienone derived from the degradation of caudatoside (1c) in pyridine solution, and the GC-MS characterization of some pterosin-type degradation products produced by reacting this solution with cosolvents is also reported.     

Ovine metabolism of lithogenic sapogenins. Synthesis of [2,2,4,4-(2)h(4)]sarsasapogenone, [2,2,4,4-(2)h(4)]sarsasapogenin,and [2,2,4,4-(2)h(4)]episarsasapogenin and evaluation of deuterium retention in a sheep-dosing trial

The suitability of [2,2,4,4-(2)H(4)]sarsasapogenone (1b), [2,2,4,4-(2)H(4)]sarsasapogenin (2b), and [2,2,4,4-(2)H(4)]episarsasapogenin (3b) as isotopically labeled dosing substrates to determine the levels of free and conjugated sapogenins present in feces from sheep grazing saponin-containing plants implicated in the development of ovine heptagenous photosentization diseases was investigated. A 1:4 mixture of [2,2,4,4-(2)H(4)]sarsasapogenin (2b) and [2,2,4,4-(2)H(4)]episarsasapogenin (3b), obtained by reduction of [2,2,4,4-(2)H(4)]sarsasapogenone (1b), was found to retain 94% of incorporated deuterium, when dosed to one sheep. The recovery of the dosed mixture of genins 2b and 3b was calculated to be 85%. Considerable loss of deuterium and a lower recovery of genin material were observed when [2,2,4,4-(2)H(4)]sarsasapogenone (1b) was dosed.     

Physical demands and low-back injury risk among children and adolescents working on farms

Little information currently exists regarding the risk of low-back disorders among youth who perform physically demanding farm activities. Thus, afield study was conducted in which children and adolescents who engage in farm work were recruited, fitted with a lumbar motion monitoring system, and then observed performing their usual chores. The lumbar motion monitor was used to record the trunk movements required while youth were performing routine manual material handling tasks on a farm. Workplace factors and motions from both males and females were recorded on over 40 farm tasks, such as feeding animals, lifting bales of hay and straw, and other miscellaneous farm chores. Although the sample size and number of observations in this study were small, the results showed that the magnitude of several work-related factors, such as weight and horizontal moment arm, and trunk motions for many farm activities were equal to or greater than those associated with high injury risk jobs previously assessed in industrial workplaces. In this study, we quantified the physical demands of tasks performed by children and adolescents on farms. In addition, the specific farm chores more likely to load the spines of youth and thereby contribute to musculoskeletal injury were identified.