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Summary Reasons for performing study Ergot alkaloids cause a range of pathological conditions in mares. There is no evaluation of the effects of ergot alkaloids from endophyte-infected tall fescue on the stallion breeding soundness examination spermiogram. Objectives The objective of this study was to investigate the effect of ergot alkaloids from endophyte-infected tall fescue on the stallion's reproductive functions. Study design Crossover toxicology experiment. Methods Six stallions were fed either toxic endophyte-infected tall fescue seed or a nontoxic endophyte tall fescue seed (Flecha AR-542, MaxQ). The fescue seed content was compounded at 45% of a grain diet and the stallions were fed the grain diet at 1% of their body weight. The stallions were fed the diet for 70 days, then rested for at least 70 days (no fescue seed) and then fed fescue seed for a second 70 days. At regular intervals blood sampling and a breeding soundness examination were performed. Results The mean time to maximal systemic toxicity was 8.33 h after starting toxic seed ingestion with a mean toxicity level of 49.98 ng alkaloid/mg creatinine. After cessation of feeding toxic seed, the systemic alkaloid concentration fell to control levels within 48 h. There were no significant changes in sperm motility, sperm concentration, sperm cell morphology, total number of sperm cells, number of breeding doses, testicular volume, baseline and human chorionic gonadotropin stimulated testosterone levels. There were no changes in core body temperature and superficial scrotal temperature. The ejaculate from stallions consuming endophyte-infected tall fescue seed had significantly lower gel-free volume (47.5 ± 4.1 ml) than stallions consuming nontoxic endophyte tall fescue seed (62.8 + 4.3 ml, P

Tall fescue (Festuca arundinacea Schreb.) is an important cool-season perennial forage naturally infected with an endophyte, Neotyphodium coenophialum Glenn, Bacon, & Hanlin, which produces ergot alkaloids. We conducted a controlled incubation study to determine the fate of C, N, and ergot alkaloids in tall fescue leaf tissue added to soil. The experimental setup was a factorial combination of endophyte-free (E-) and endophyte-infected (E+) leaf tissue (short term) incubated in soil exposed to 10 yr of E- and E+ tall fescue pasture (long term). Soil history of E+ compared with E- reduced C mineralization per unit of soil organic carbon (52 vs. 55 mg g -1 SOC) and the fraction of inorganic N as nitrate (0.68 vs. 0.72 g g -1 ), but increased ergot alkaloid concentrations in soil sediment ( 1 mm + remaining leaves; 5.8 vs. 2.2 ng g -1 ), and water extract (0.27 vs. 0.22 ng g -1 soil). Short-term exposure of soil to E+ leaves compared with E- leaves reduced C mineralization (660 vs. 688 μg g ' soil) and soil microbial biomass C (487 vs. 583 μg g -1 soil), but increased net N mineralization (70 vs. 59 μg g -1 soil), soil microbial biomass N (56 vs. 19 μg g -1 soil), and ergot alkaloid concentration in the coarse fraction (0.36 vs. 0.27 μg g ' original leaf). Both short- and long-term exposure of soil to E+ tall fescue were affecting soil organic matter dynamics by altering biochemical transformations of C and N. Our results suggest that wild-type E+ tall fescue can alter soil organic C storage through a reduction in soil microbial activity. This research has also demonstrated the presence of ergot alkaloids in soil under E+ tall fescue.

Persistence of endophyte-free (E-) tall fescue ( Festuca arundinacea Schreb.) is erratic. Little information exists as to how fast endophyte ( Neotyphodium coenophialum )-infected (E+) tall fescue might encroach on E- tall fescue and whether specific conditions might influence the speed of encroachment. Plots of E+ and E- tall fescue genotypes 7 and 17 were established using a modified Nelder's design to compare performance of the E+ forms of the plants in pure and mixed communities at different population densities. The plots were planted at the USDA Southern Piedmont Conservation Research Laboratory in Watkinsville, Georgia, and the University of Georgia Plant Sciences Farm in Bogart, Georgia. Plants were grown over a 5 year period and dry matter yield monitored 1, 3, and 5 years after establishment. Relative crowding coefficients were calculated for each to establish trends of encroachment of the E+ on the E- plants in the mixed communities. Generally, dry matter yields of E+ tall fescue were greater than E- tall fescue regardless of whether they were grown in pure or mixed communities. As time progressed, the difference in dry matter yield between E+ and E- tall fescue grown in mixed communities was greater than that of the pure communities. Relative crowding coefficients increased as time progressed. Relative crowding coefficients at the Watkinsville location were greater after 5 years than those at the Plant Sciences Farm. Therefore, site specific conditions exist which affect the competitiveness of E- tall fescue and degree of encroachment by E+ tall fescue. Research is needed to identify which biotic, abiotic and management variables exacerbate encroachment of E+ tall fescue to better define the conditions which best suit E- tall fescue.

Tall fescue (Festuca arundinacea Schreb.) plants infected by the fungal endophyte Neotyphodium coenophialum (Morgan-Jones & Gams) (Glenn et al., 1996) often perform better than noninfected plants, especially in marginal resource environments. There is a lack of information about endophyte related effects on the rhizosphere of grasses. In a greenhouse experiment, four endophyte-infected (E+) tall fescue clones (DN2, DN4, DN7, DN11) and their endophyte-free (E−) forms were grown in limed (pH 6.3) Porter soil (low fertility, acidic, high aluminum and low phosphorus content, coarse-loamy mixed mesic Umbric Dystrochrept) at three soil P levels (17, 50, and 96 mg P kg-1 soil) for five months. Excluding the genotype effect, endophyte infection significantly increased cumulative herbage DM yield by 8% at 17 mg P kg-1 soil but reduced cumulative herbage DM yield by 12% at 96 mg P kg-1 soil. With increased P availability in the soil, shoot and root DM, and root/shoot ratio in E+ plants were significantly less when compared to E− plants. Endophyte infection increased specific root length at 17 and 50 mg P kg-1soil. At soil P level of 17 mg P kg-1soil, E+ plants had significantly higher P concentrations both in roots and shoots. Similar relationships were found for Mg and Ca. E+ plants had significantly higher Zn, Fe, and Al concentration in roots, and lower Mn and Al concentration in shoots when compared to E− plants. Ergot alkaloid concentration and content in shoot of E+ plants increased with increasing P availability in the soil from 17 to 50 mg P kg-1 but declined again at 96 mg P kg-1 soil. Ergot alkaloid accumulation in roots increased linearly with P availability in the soil. Results suggest that endophyte infection affects uptake of phosphorus and other mineral nutrients and may benefit tall fescue grown on P-deficient soils. Phosphorus seems also to be involved in ergot alkaloid accumulation in endophyte-infected tall fescue.

Endophyte-free tall fescue (Festuca arundinacea Schreb.) furnishes better animal performance than endophyte- infected grass but is less persistent under grazing, especially in mixture with common bermudagrass [Cynodon dactylon (L.) Pers]. Rotational (RS), compared with continuous (CS), stocking of endophyte-free tall fescue may improve persistence when grown with an aggressive warm season perennial grass. Four 40-acre bermudagrass pastures no-till seeded witb endophyte-free 'AU Triumph' tall fescue were used, allowing two replications to compare CS and RS methods. Rotationally stocked pastures were divided into 12 paddocks to allow 2 d of grazing and 22 d of rest. Twenty Hereford (Bos taurus)x Brangus (B. indicus x B. taurus) beef cows/40-acre pasture were maintained year around for 3 yr with additional cows added in spring and summer to maintain similar forage availability. Grazing method had no effect on cow weight change, pregnancy rate, or calf weaning weight. Pasture stocking rate and calf weaning weight per acre were 38 and 37% higher (P < 0.10), respectively, and winter hay consumption was 31% lower from rotationally stocked pastures because of better tall fescue persistence and forage availability. Crude protein (CP) and in vitro dry matter digestibility of available forage generally exceeded 8 and 50%, respectively, throughout the year. Rotational stocking appears to be useful in maintaining stands of endophyte-free tall fescue in bermudagrass pastures.

A controlled environment experiment was conducted to determine the influence of defoliation on the regrowth and development of two tall fescue (Festuca arundinacea Schreb.) host-endophyte (Neotyphodium coenophialum MorganJones and Gams (Glenn, Bacon, Price and Hanlin comb. noa.) associations (DN2 and DN11), known to dier in morphology and alkaloid production capacity. Defoliation treatments included an uncut control, and clipping to a 5- or 10-cm residue height. In a separate experiment, leaf age eects were determined on an uncut plant canopy. Ergot alkaloid concentration was greatest in pseudostem and least in harvested leaf. Non-infected plants were devoid of alkaloid. Alkaloid production (expressed as a function of dry matter) and yield were greater in uncut than clipped plants, and were greater in DN11 than DN2 plants. Alkaloid production increased with increasing N concentration in both associations; however, the rate of production was influenced by concentration of non-structural carbohydrate. Leaf age influenced leaf mass and alkaloid concentration and yield. Oldest leaves (" 6 weeks after appearance) of DN2 and DN11 had the lowest concentrations of ergot alkaloid, while leaves that were 2 to 4 weeks old had the greatest alkaloid concentration and yield (alkaloid concentration‹leaf mass). Repeated defoliation reduced the production of alkaloids, but did so as a function of non-structural carbohydrate. Our data suggest that alkaloid production can be modified by defoliation as well as by host-endophyte association. # 1997 Annals of Botany Company

The aim of this study was to utilise the Quality Enhancement Research Initiative in Systemic Sclerosis (QuERI-SSc) to measure and reduce a perceived gap in the diagnosis of pulmonary arterial hypertension (PAH) associated with systemic sclerosis (SSc).Rheumatologists enrolled patients with SSc (aged ≥ 18 years) and provided data on a panel of diagnostic tests over 3 years. Pulmonary function testing, echocardiography, 6-minute walk distance, N-terminal pro-brain natriuretic peptide assays, high-resolution computed tomography of the lungs, and ventilation/perfusion scan plus right heart catheterisation (RHC; when appropriate) were emphasised. Exclusion criteria included previously documented PAH, interstitial lung disease, and SSc overlapping with other connective tissue disease.Participating rheumatologists enrolled 207 patients with SSc (90% female; 80% white), with a median age of 57 years and median disease duration of 5 years. A total of 82% of patients were classified as New York Heart Association functional class I and II; of these patients, 177 had an echocardiogram at enrolment and 191 at any time during the study. Of those who met study-specified criteria for RHC at enrolment, only 3 of 7 patients underwent RHC.The screening algorithm was successful in identifying patients with mild impairment. Although specific tools were recommended for screening PAH in patients with SSc, results indicate that significant diagnostic care gaps still exist in the general rheumatology community. Better understanding and adherence to guidelines could improve the care and, ideally, outcomes of these high-risk patients.

Ergot alkaloids cause a range of pathological conditions in mares. There is no evaluation of the effects of ergot alkaloids from endophyte-infected tall fescue on the stallion breeding soundness examination spermiogram.The objective of this study was to investigate the effect of ergot alkaloids from endophyte-infected tall fescue on the stallion's reproductive functions.Crossover toxicology experiment.Six stallions were fed either toxic endophyte-infected tall fescue seed or a nontoxic endophyte tall fescue seed (Flecha AR-542, MaxQ). The fescue seed content was compounded at 45% of a grain diet and the stallions were fed the grain diet at 1% of their body weight. The stallions were fed the diet for 70 days, then rested for at least 70 days (no fescue seed) and then fed fescue seed for a second 70 days. At regular intervals blood sampling and a breeding soundness examination were performed.The mean time to maximal systemic toxicity was 8.33 h after starting toxic seed ingestion with a mean toxicity level of 49.98 ng alkaloid/mg creatinine. After cessation of feeding toxic seed, the systemic alkaloid concentration fell to control levels within 48 h. There were no significant changes in sperm motility, sperm concentration, sperm cell morphology, total number of sperm cells, number of breeding doses, testicular volume, baseline and human chorionic gonadotropin stimulated testosterone levels. There were no changes in core body temperature and superficial scrotal temperature. The ejaculate from stallions consuming endophyte-infected tall fescue seed had significantly lower gel-free volume (47.5 ± 4.1 ml) than stallions consuming nontoxic endophyte tall fescue seed (62.8 + 4.3 ml, P0.01).Ergot alkaloids decreased the gel-free volume of stallions consuming high levels of ergot alkaloids but statistically significant effects on the spermiogram of adult breeding stallions were not found.

Alfalfa (Medicago sativa L.) has not been well suited for pasture because of its intolerance to grazing. 'Alfagraze', a cultivar bred for grazing tolerance, offers potential to use alfalfa as pasture. A 3-yr grazing study was initiated in central Georgia to investigate persistence and animal performance of 'Apollo' and Alfagraze alfalfa at low, medium, and high forage allowance (FA). The FA for this study were targeted at 1000, 2000, and 3000 lb dry matter (DM)/1100 lb animal unit for low, medium, and high FA, respectively. Low FA reduced stand of both cultivars (P < 0.05) after only 1 yr (low = 6.8, medium = 8.2, high = 8.8 plants/sq ft). After 2 yr, high FA paddocks averaged 8.6 plants/sq ft, while medium and low FA had decreased to 5.4 and 4.4 plants/sq ft, respectively. The difference in grazing tolerance between cultivars became evident after 2 yr of grazing, when, averaged across FA, Alfagraze had 7.3 plants/sq ft and Apollo had 5.0 plants/sq ft. After an additional year of continuous stocking, Alfagraze had approximately 150% more plants than Apollo. Persistence differences between cultivars were most evident at low FA. After 2 yr of low FA, Alfagraze had 5.5 and Apollo had 3.3 plants/sq ft. After 3 yr, Alfagraze maintained stands of 5.5 plants/sq ft, while Apollo stands decreased to 1.5 plants/sq ft. Lower FA resulted in greater bermudagrass [Cynodon dactylon (L.) Pers.] encroachment. Lower FA decreased average daily gain (ADG) in yr 1. At low FA, improved persistence of Alfagraze resulted in 0.45 Ib/d higher ADG than Apollo in yr 2. The better grazing-tolerance of Alfagraze alfalfa resulted in longer stand persistence and better animal performance.

The mutualistic association between Acremonium coenophialum Morgan-Jones and Gams and its tall fescue (Festuca arundinacea Shreb.) host provides plant scientists with unique opportunities to create superior turf and forage cultivars. The objectives of this research were to determine endophyte-mediated drought acclimation in tissue-cultured regenerants of tall fescue containing one of three A. coenophialum isolates during short- and long-term drought stress. Two experiments were conducted by growing vegetative propagules of plants with endemic or introduced endophytes in 120-L tubs containing fritted clay : one experiment examined water relations during a 15-d drought period and the other during a 70-d water stress period. Leaf water potential and turgor pressure responses to soil water content differed among infected and non-infected plants, among endophytes inserted within a plant genotype, and among plant genotypes containing a common endophyte during 15 d of stress. Among endophytes, only EDN11 induced acclimation to 70 d of stress when inserted into plant genotype PDN2. Leaf water potential and turgor pressure were approximately 0.50-0.75 MPa greater when PDN2 was infected with EDN11 compared to other endophytes during the 70 d of stress. Endophyte had no effect on leaf osmotic potential and minimal effect on plant water soluble mineral and sugar concentrations, and endophyte-mediated adaptation to drought stress was an avoidance mechanism. Because enhanced drought tolerance is a result of specific interactions between plant genotypes and endophyte isolates, selection of endophytes specifically for enhancing drought tolerance in tall fescue is not likely to have a general effect on the plant population.

Clones of tall rescue (Festuca arundinacea Schreb.) regenerated from tissue culture are required for examining interactions between the endophyte, Acremonium ¢oenophialum Morgan-Jones and Gams, and its host. Somaclonal variation is common among regenerated plants, and could limit the utility of this technology to study the interactions of tall rescue and its endophyte. Various methods are used to detect somaclonal variation, but there is little agreement as to the relative advantages of each. Therefore, the objectives of this study were to determine (i) whether somaclonal variation exists among tall rescue plants regenerated from somatic embryos, and (ii) whether pollen viability, yield, morphological tr its, or phenologieal development give consistent estimates of somaclonal variation. Seven regenerants from non-infected tall rescue genotype PDN2 and a nonregenerated PDN2 control were planted in the field in five replications. Plants were screened for somadonal v riation by phenological development, vegetative and flag leaf width/length ratios, total biomass, eed yield, and pollen viability over 2 yr. Although regeneration protocols were designed to minimize somaclonal variation, somaclonal variation of quantitative traits was observed. Total biomass and seed yield of regenerants, used together, were most consistent in detecting somaclonal variation. When using tissue culture to insert endophytes into tall rescue, we found multiple regenerants need to be infected with each isolate of endophyte to ascertain whether differences among response variables are due to cndophyte or somaclonal variation. S STRATEGIES have been used to study interactions between tall fescue and its fungal endophyte. One method is to infect clones of a common tall fescue genotype with different endophyte isolates to assess endophyte-mediated changes in the plant (Hill et al., 1991b). Infection of clones of a common tall fescue genotype with different endophyte isolates necessitates the use of plant tissue culture techniques (Kearney et al., 1991) because the endophyte will not infect mature tall fescue plants (Bacon and Siegel, 1988). A concern of using tissue culture to study tall fescue/endophyte interactions is the possibility that somaclonal variation may confound the effect of an endophyte, making it difficult to assess the endophyte’s contribution to plant responses. Concomitant with concerns that somaclonal variation exists, is the ability to document its existence. Traits that have been evaluated to detect somaclonal variation in plants include pollen viability, plant morphology, phenology, and yield. Eizenga and Dahleen (1990) used pollen viability to identify somaclonal variation in tall fescue, while others have used leaf width/length ratios (Cummings et al., 1976), plant height (Hanna et al., 1984), heading and flowering dates, or seed yield (Stephens et al., 1991) as traits for other species. There is no consensus as to which traits consistently detect somaclonal variation. Possible reasons for the lack of consensus are that (i) the traits chosen by individual J.T. Royiance, N.S. Hill, and W.A. Parrott, Dep. of Crop & Soil Sciences, Univ. of Georgia, Athens, GA 30602-7272. Received 13 Sept. 1993. *Corresponding author (nhill@uga.cc.uga.edu). Published in Crop Sci. 34:1369-1372 (1994). investigators are those which are easiest to measure, (ii) traits may be affected by genotype x environmental interactions, and (iii) selected traits are not always based on a variety of unrelated characters (De Klerk, 1990). Therefore, the objectives of this study were to determine (i) whether quantitative traits were affected by somaclonal variation in tall fescue plants regenerated from somatic embryos; and (ii) examine if pollen viability, yield, morphological traits, or phenological development are the most consistent variables to use when screening for somaclonal variation. MATERIALS AND METHODS Plants regenerated by somatic embryogenesis (Kearney et al., 1991) were used in this experiment. Explants were taken from meristematic regions at the base of elongating tillers from the endophyte-free tall fescue genotype PDN2. The explants were surface-sterilized in a commercial bleach solution (10.5 L-t NaCIO3) for 30 sec and in 700 mL -1 EtOH solution for 3 rain. Explants were rinsed three times with sterile water, cut into 2.5-cm lengths, and placed on a basal medium to induce callus formation. The embryonic medium consisted of MS salts (Murashige and Skoog, 1962), B5 vitamins (Gamborg et al., 1968), 30 g -t sucrose, 3 0 gM 2,4-D, a nd 20 g L-l Gelrite (Gibson Laboratories, Inc., Lexington, KY) as solidifying agent. The pH of the medium was adjusted to 5.8 prior to autoclaving. Cultures were placed in a growth room with 30 gM m-2 sec-~ photon flux density provided by cool white fluorescent tubes; daylength was maintained at 23 h and temperature at 26 + 1 °C. After 28 d on embryonic medium, calli were transferred to auxin-free basal medium to permit growth and development of somatic embryos. Germinating embryos were excised from the calli and placed in GA-7 containers (Magenta Corp. Chicago, IL) with auxin-free basal medium with a sucrose level of 6 g L-1. After 28 d, plants were transferred to soil and allowed to harden. The plants were transferred to the greenhouse and placed in 4-L pots containing a 1:1:1 mixture of Cecil sandy clay loam soil (Typic Kanhapludult, mixed, mesic, thermic)/peat/perlite. Of 77 endophyte-free regenerated plants (Kearney et al., 1991), regenerants R12, R16, R19, R22, R30, R37, and R40 of tall fescue genotype PDN2 were randomly selected for this experiment. Individual tillers were taken from each regenerated plant, cut to 5-cm lengths and screened for a uniform mass of 2 g fresh weight. They were also screened so each contained two visible tiller primordia at the basal node. Fifteen tillers were selected from each regenerant and transplanted into 10-cm pots containing the soil mixture used previously, and grown in the greenhouse for 28 d. The same was done for tillers from the non-regenerated parent plant PDN2. Five plants of each regenerant were selected only if they had developed three fillers with two expanded leaves on each filler. This was conducted to assure that all plant materials were physiologically and developmentally uniform, thereby reducing variability within and among regenerants that could be attributed to the physiological condition of the vegetative propagules. On 1 Oct. 1990, the regenerants were transferred to the Abbreviations: FWL, flag leaf width/length ratio; VWL, vegetative leaf width/length ratio; PCSAS, statistical analysis systems for personal com

To assess maturity distributions of shelled-stock peanut lots, a method was developed to characterize peanut kernels into one of three possible maturity classes based on testa texture and color and kernel shape. Kernels having testa with longitudinal wrinkles, a raisin-like texture, light color and slightly elongated shape were classed Immature and predominately were shelled from pods in the Hull-Scrape categories White, Yellow I, and early-Yellow II. Kernels with a smooth testa, pink to dark pink and with a more rounded appearance were classed Mid-mature and predominately were shelled from pods in the late-Yellow II, Orange, and early-Brown Hull-Scrape classes. Kernels with a waffle-like surface texture, dark pink to brown testa, and a more rounded appearance were classed as Mature, and predominately were shelled from pods in the mid-and late-Brown and the Black Hull-Scrape categories. Attempts to automate the system using color alone were unsuccessful; to be a reliable maturity sorting technique, both testa texture and color pattern had to be considered.

Previously, a monoclonal antibody was developed to the lysergic ring common to ergoline alkaloids (EA). The objectives were to develop an immunoassay for EA in tall fescue by dertermining (i) time requirement; (ii) tissue mass, and (iii) optimum volume of extraction solution necessary for detection protocols with repeatable results; and (iv) the acceptability of oven- versus freeze-dried samples. A competitive enzyme-linked immunosorbent assay (ELISA) was conducted on plant extracts (0-548 μg kg -1 ergovaline)

Competitiveness and persistence of tall fescue (Festuca arundinacea Schreb.) is superior when infected with the endophyte, Acremonium coenophialum Morgan-Jones & Gams. Acremonium-derived ergopeptine alkaloids impair animal productivity, and if reduced or eliminated would improve animal performance. This study was conducted to determine: (i) environmental influence on ergovaline concentration in A. coenophialum-infected tall fescue genotypes, and (ii) the extent that plant genotype influences ergovaline production by the endophyte. A field experiment evaluated five endophyte-infected tall fescue genotypes grown at three locations (environments) during 1 yr. Plant genotypes, harvested every 28 d, differed in ergovaline concentration (P

Growth room and field experiments were conducted to determine the influence of soil temperature and soybean phenology on dormancy induction of a North Carolina population of Heterodera glycines race 1. Three temperature regimes and two photoperiods to regulate plant phenology were investigated in growth rooms. H. glycines hatch was greatest from the 26 and 22 C (day and night) temperature treatment, intermediate at 22 and 18 C, and least from the decreasing regime (26 and 22 C, 22 and 18 C, and 18 and 14 C). More eggs hatched and greater nematode reproduction occurred on pod-producing soybeans than on those that remained vegetative. In the field study, hatching patterns were not different between depodded and naturally senescing soybeans nor between the different maturity groups of soybean cultivars (groups V through VIII). Egg hatch (9-16%) was greatest in August and September when mean soil temperatures were between 25 and 29 C. Hatch declined to 1% in vitro and was not detectable in the bioassay in November. Greatest nematode numbers were observed on the latest maturing cultivar (group VIII) and fewest on the cultivar which matured earliest (group V). Decreasing temperature appears to be more important than soybean phenology in dormancy induction of H. glycines.

Nineteen sorghum, Sorghum bicolor (L.) Moench, accessions were compared with the standard commercial cultivar ‘Northrup King Savanna 5’ for hard-dough stage panicle resistance to feeding by larvae of the fall armyworm, Spodoptera frugiperda (J. E. Smith). The biological variables measured to determine the differential development of S. frugiperda on diets containing florets of the sorghum genotypes were larval and pupal weight, duration of the larval stage, time to adult emergence, survivorship, fecundity, net reproductive rate, intrinsic rate of increase, and relative fitness. The plant introductions IS1340C, IS2246C, IS2403C, IS2553C, IS2569C, IS2825C, IS3477C, IS6911C, IS7007C, IS7498C, IS8337C, IS12219C, IS12592C, IS12612C, IS12617C, IS12662C, IS12664C, IS12666C, and IS12683C were all found more resistant than ‘Northrup King Savanna 5’, which is the most resistant commercial genotype available. Resistance in IS1340C, IS2246C, IS2403C, IS2553C, IS3477C, IS6911C, IS7007C, IS7498C, IS12612C, IS12662C, IS12664C, and IS12666C was primarily due to factors in the glumes (including lemmas and paleas). Chemical components in the seed were mainly responsible for resistance in IS2825C, IS12617C, and IS12683C, whereas factors in both seed and glumes were responsible for the resistance shown by IS12219C and IS12592G. Resistance was significantly correlated ( r 2 > 0.50, P < 0.05, n = 16) with the concentration of acid detergent fiber and tannin in the seed.

The aviability of a tall fescue (Festuca arundinacea Schreb.) clone whose members are infected with different strains of its endophytic fungus, Acremonium coenophialum Morgan-Jones & Gams, would help identify the individual contributions of the endophyte and tall fescue toward traits normally associated with endophyte-infected tall fescue plants

Low forage quality of sericea lespedeza [Lespedeza cuneata (Dum.- Cours.) G. Don] herbage is associated with the presence of condensed tannins in the leaves, and tannin-protein complexes that render digestive enzymes inactive. Experiments were conducted to (i) determine the type of inhibition of the cellulase complex caused by tannins, (ii) evaluate N-containing supplements that preferentially bind to tannins and restore cellulase activity, (iii) determine the effect of such supplements on the in vitro dry matter digestibility (IVDMD) of cellulose, and (iv) determine their effect on IVDMD of high- and low-tannin sericea herbage. The type of enzyme inhibition was determined by Michaelis-Menten kinetics; a double-reciprocal plot of the data revealed that tannins inhibited cellulase enzymes noncompetitively. Cellulase activity in tannin-containing solutions increased with increasing amounts of N-containing supplements, except for urea. Ovalbumin, polyvinylpyrrolidone (PVP), and gelatin resulted in greatest saccharification: hemoglobin and β-casein were less effective. Gelatin, hemoglobin, PVP, and ovalbumin partially overcame the effects of exogenous tannins on IVDMD of cellulose, but the proteins were more effective than PVP. The IVDMD of herbage from high- and low-tannin cultivars was greatest when PVP or ovalbumin were added; less supplement was needed in the low-tannin cultivar. We conclude that N-containing supplements improve digestibility and, consequently, may improve the performance of animals consuming sericea lespedeza forage.

Differential developmental responses of fall armyworm, Spodoptera frugiperda (] . E. Smith), were compared after larvae were fed milk stage spikelets (complete florets) of field-grown converted sorghum ( Sorghum bleolor (L.) Moench) accessions incorporated into a meridic diet. Larvae fed diet supplemented with spikelets of ‘International Sorghum (IS) 12592 Converted (C)’ were significantly smaller compared with those fed diet supplemented with spikelets of the released resistant hybrid ‘Northrup King Savanna 5’. Feeding on diet containing the genotypes‘ISI34OC’,‘IS2246C’,‘IS2569C’,‘IS7498C’,‘IS12617C’, or ‘IS12683C’ resulted in a significantly longer duration of the larval stage of fall armyworm than feeding on diet containing the resistant check NK Savanna 5. Pupal weights of fall armyworm that were fed diet supplemented with ‘IS2403C’, ‘IS2569C’, ‘IS7498C’, ‘IS12617C’, or ‘IS12657C’ were significantly less compared with those of fall armyworm fed the resistant check. Weights of fall armyworm larvae were positively correlated with higher concentrations of crude protein (total nitrogen) in sorghum spikelets. The concentrations of lignin were inversely correlated with the duration of the larval development. When resistant and susceptible sorghum genotypes were considered separately, the concentration of tannin and the ratio of lignin/neutral detergent fiber were negatively correlated with the duration of the larval development in the resistant genotypes but positively correlated in the susceptible genotypes.

Tall fescue (Festuca arundinacea Schreb.) is a common pasture grass adapted to a wide range of environmental conditions. An endophyte, Acremonium coenophialum Morgan-Jones & Gams, growing in association with tall fescue in known to produce ergopeptine alkaloids that are thought to be detrimental to animal health. Endophyte infection changes how tall fescue plants grow and may be involved in the adaptability of tall fescue to environmental extremes

(1991). Effects of Various Culture Media, Antibiotics, and Carbon Sources on Growth Parameters of Acremonium Coenophialum, The Fungal Endophyte of Tall Fescue. Mycologia: Vol. 83, No. 1, pp. 110-115.

(...) The objectives of this study were to determine variability in responses of tall fescue genotypes to endophyte infection for select growth characteristics, plant morphology, and chemical components. Five genotypes of tall fescue were grown in both endophyte-infected (EI) and noninfected (NI) forms in the greenhouse under different clipping treatments. Tiller and dry matter production, crown depth, and total nonstructural carbohydrates (TNC) were measured (...)

Pulmonary rehabilitation programs use multidisciplinary teams to optimize physical and social functioning of patients with chronic respiratory impairment. These programs provide rehabilitation in inpatient, outpatient, or home settings, using at least three sessions weekly (one may be unsupervised) for at least 6 wk. The programs usually consist of exercise training, education, and psychosocial/behavioral components. Upper extremity exercises and instruction on breathing technique are included in most rehabilitation programs and reduce dyspnea, but the contribution of these to improved functional capacity remains unproven. Decreases in the sensation of dyspnea, increased functional exercise capacity, and enhanced quality of life of patients with chronic obstructive pulmonary disease (COPD) are established benefits of pulmonary rehabilitation. Evidence is lacking for the efficacy of rehabilitation for patients with non-COPD causes of pulmonary impairment, but many of these patients probably benefit. Despite the availability of strong evidence to support the efficacy of pulmonary rehabilitation programs in patients with severe COPD, third-party reimbursement policies have been inconsistent. Nonetheless, enrollment in a pulmonary rehabilitation program is encouraged for all appropriate candidates with chronic respiratory impairment, particularly for those with severe COPD.

The monoclonal antibodies previously used to determine the role of ergot alkaloids in fescue toxicosis have higher affinity to lysergic acid amides than to ergopeptine alkaloids. The objective of this research was to find monoclonal antibodies with uniform affinity to all ergot alkaloid classes. Balb/C mice were immunized with ergonovine-protein conjugates. Splenic hybridoma cell lines were compared with current antibodies for cross reaction with lysergic acid amide and ergopeptine alkaloids. Antibodies from two cell lines had more uniform affinity to both ergot alkaloid classes and should be useful for determining the role of ergot alkaloids in fescue.

Non-invasive ventilation (NIV), the provision of ventilatory assistance without the need for airway invasion, has seen increasing use in critical care units to avoid endotracheal intubation and its attendant complications [1-3]. Evidence has been rapidly accumulating to support many applications of NIV in the acute setting. NIV is also widely applied in the long-term setting, but a discussion of these applications is beyond the scope of this chapter. The following will make recommendations on current indications of NIV in the acute setting, based on the supporting evidence (Table 1).

Consumption of wild-type (toxic) endophyte-infected tall fescue (E+) by horses during late gestation is known to adversely affect pregnancy outcome; however, little is known of the potential disruptive consequences of E+ consumption by mares during the critical phases of placentation and fetal development in early pregnancy. The objective of this study was to evaluate the detrimental effects of feeding E+ to mares during early gestation. Mares (n = 12) paired by stage of gestation (d 65 to 100) were assigned to diets (six per diet) consisting of endophyte-free (E-) or E+ tall fescue seed (50% E- or E+ tall fescue seed, 45% sweet feed, and 10% molasses fed at 1.0% of BW/d). Mares also had ad libitum access to E+ or E- annual ryegrass hay, and were fed diets for 10 d. Following removal from the tall fescue diet on d 11, mares were placed on common bermudagrass pasture and monitored until d 21. Morning and evening rectal temperatures were recorded and daily blood samples were collected for progesterone and prolactin (PRL) analyses, whereas samples for 3,4-dihydroxyphenyl acetic acid (a catecholamine metabolite) analysis were collected on alternate days. For clinical chemistry analysis, blood samples were collected on d 0, 5, 10 and 21. Daily urine samples were collected for ergot alkaloid analysis, and ultrasonography was performed for presence of echogenic material in fetal fluids. Rectal temperatures (E+ 37.76+/-0.03; E- 37.84+/-0.03 degrees C) and serum PRL concentrations (E+ 14.06or =0.76; E- 12.11+/-0.76 ng/mL) did not differ (P = 0.96) between treatments. Measuring the change in basal serum concentration from d 0 over time, progesterone concentrations did not differ (-0.64 +/-1.49 and -0.55+/-1.47 ng/mL for E+ and E- mares, respectively). There was no negative pregnancy outcome, and ultrasonography indicated no increase in echogenic material in fetal fluids. Plasma 3,4-dihydroxyphenyl acetic acid concentrations decreased (P0.05) in E+ compared with E- mares (2.1+/-0.14 and 4.4+/0.43 ng/mL, respectively). Urinary ergot alkaloid concentration was greater (P0.01) in mares consuming E+ compared with E- (532.12+/- 52.51 and 13.36+/-2.67 ng/mg of creatinine, respectively). Although no fetal loss was observed during the current study, elevated concentrations of urinary ergot alkaloid were consistent with depressed endogenous catecholamine activity, suggestive of an endocrine disruptive effect of hypothalamic origin.

Grazing studies were conducted to determine cattle growth performance, evaluate toxicosis, and compare grazing behavior in stocker cattle grazing nonergot alkaloid-producing endophyte-infected (AR542 or AR502), endophyte-free (E-), or wild-type toxic endophyte-infected (E+) Jesup, Georgia-5, and Kentucky-31 tall fescue. Replicated 0.81-ha tall fescue paddocks were established at the Central Georgia Branch Station at Eatonton and the Northwest Georgia Branch Station at Calhoun during October 1998 and were stocked with beef cattle for autumn and spring periods from fall 1999 through spring 2002. Mean ergot alkaloid concentrations were higher (P0.01) on E+ pastures than the other treatments at both locations. At Calhoun and Eatonton, post-treatment serum prolactin concentrations were decreased (P0.01) on E+ compared with AR542, AR502, and E- tall fescue. Cattle on AR542, AR502, and E- pastures had lower (P0.05) post-treatment rectal temperatures than cattle grazing E+ tall fescue during spring at Eatonton and Calhoun. Calf ADG was higher (P0.05) on AR542, AR502, and E- as compared with E+ tall fescue during autumn and spring grazing at Eatonton, and at Calhoun, cattle on E+ pastures had lower (P0.05) ADG in both autumn and spring. Gain/hectare was higher (P0.05) on AR542, AR502, and E- than on E+ during autumn at Eatonton and during spring at both locations. In autumn at Calhoun, gain/hectare was greater (P0.05) on AR502 and E- compared with E+ tall fescue. During April, May, and June, cattle grazing E+ pastures at Eatonton spent more (P0.01) time idling, more (P0.01) time standing, and used more (P0.01) water than cattle on AR542 and E- tall fescue. Daily prehensions and biting rate were each higher (P0.01) on AR542 and E- tall fescue than E+ tall fescue in both grazing seasons. There were no differences among pasture treatments for bite size in either spring (P = 0.50) or autumn (P = 0.34). Steers grazing E+ pastures had lower DMI than steers grazing AR542 and E- pastures during spring (P0.10) and lower DMI than steers grazing E- pastures during autumn (P0.05). Daily steer water usage was decreased (P0.10) in E+ pastures compared with AR542 and E- pastures during late fall. These results indicate that nonergot alkaloid-producing endophyte technology is a promising option for alleviating tall fescue toxicosis in stocker cattle.

Phytoestrogens derived from soybeans reverse endothelial dysfunction in a number of animal models of systemic vascular disease. Based on these studies, we hypothesized that phytoestrogens would reverse chronic hypoxia-induced endothelial dysfunction in rat pulmonary arteries. To test this hypothesis we examined the effect of genistein, the major phytoestrogen found in soybeans, on carbachol-induced relaxation in phenylephrine-constricted pulmonary artery rings isolated from normoxic rats and rats exposed to 14 days of hypobaric hypoxia. Compared with that in normoxic rats, the response to carbachol was impaired in pulmonary arteries isolated from rats exposed to chronic hypoxia. In normoxic rat pulmonary arteries, genistein (30 microM) did not change the maximum relaxation to carbachol. In contrast, genistein significantly enhanced the relaxation response to carbachol in pulmonary arteries from hypoxic rats, restoring it to the levels seen in normoxic rats. 17beta-estradiol (10 microM) and daidzein (30 microM), a structural analog of genistein lacking inhibitory effects on tyrosine kinases, also restored the relaxation response to carbachol in hypoxic rat pulmonary arteries. The nitric-oxide synthase inhibitor N(omega)-nitro-L-arginine (100 microM) completely blocked the genistein, daidzein, and 17beta-estradiol-induced restoration of the relaxation response to carbachol, whereas the estrogen receptor antagonist ICI 182,780 (10 microM) had no effect on the relaxation responses. We conclude that the phytoestrogens genistein and daidzein act like estrogen in restoring nitric oxide-mediated relaxation in chronically hypoxic rat pulmonary arteries and that this effect does not appear to be mediated by inhibition of tyrosine kinases or by known estrogen receptors.

To evaluate the short- and long-term effects of intravenous epoprostenol in patients with pulmonary hypertension (PH) associated with systemic sclerosis (SSc).Sixteen patients with SSc-associated PH and New York Heart Association (NYHA) class III or IV symptomatology underwent right heart catheterization for determination of baseline hemodynamic values. Vasoreactivity was assessed with either inhaled nitric oxide or intravenous adenosine. After a medication washout period, all patients received intravenous epoprostenol in incrementally increasing doses; tolerance was assessed according to symptoms and hemodynamic findings at each dose increment and at the conclusion of the medication trial. Once a stable medication regimen was established, patients were discharged and followed up as outpatients for assessment of symptoms and exercise tolerance as measured by change in the NYHA class. Repeat hemodynamic testing was performed in 4 patients at 1 year and in 2 patients at 2 years of treatment.Therapeutic response to epoprostenol, defined by a reduction in the pulmonary vascular resistance ofor =25%, was achieved in the short-term treatment period in 13 of 16 patients (81.3%). Improvement in symptoms and exercise tolerance occurred in all patients, and a significant short-term hemodynamic response was observed. Followup hemodynamic tests revealed persistent favorable responses in all 4 of the patients studied.Most patients with PH secondary to SSc manifest favorable hemodynamic responses to epoprostenol in the short term. Long-term epoprostenol was generally well tolerated and provides a potential therapeutic option for patients with PH secondary to SSc.

The fungal endophyte, Acremonium coenophialum Morgan-Jones & Gams, is present in many tall fescue (Festuca arundinacea Shreb.) pastures. It imparts fitness-related traits to the tall fescue plant but produces ergopetine alkaloids, which may be the cause of fescue toxicosis in grazing livestock. Inasmuch as the endophyte-infected tall fescue populations that are incapable of producing ergopeptine alkaloids may be a solution to providing a sustainable nontoxic grass base for livestock producers

Pericardial effusion was noted in 43 of 79 patients (54%) with severe primary pulmonary hypertension. Larger effusion was associated with hemodynamic and echocardiographic evidence of right heart failure, impaired exercise tolerance, and a poor 1-year prognosis.

The successful management of outpatients with COPD requires a multifaceted approach that includes prophylactic, palliative, and life-extending therapies. All patients should undergo smoking cessation, avoid potentially harmful environments, and receive influenza and pneumococcal vaccines at recommended intervals. Although medical therapy may yield only marginal benefits in patients with minimal airway responsiveness, even small improvements may translate into significant functional benefits and will be greatly appreciated. Therefore, every effort should be expended to optimize the patient's medical regimen and to ascertain that methods of delivery (such as use of spacers) are as recommended. Physical therapy measures may be useful in patients with copious sputum production, and pursed-lip and diaphragmatic breathing exercises may reduce dyspnea and lend a sense of control to patients with severe flow limitation. Oxygen therapy is the only modality demonstrated to improve survival in patients with severe COPD and may give symptomatic relief to some patients. Its use, however, is restricted to patients meeting guidelines for hypoxemia, and although dyspneic patients not meeting these guidelines may desire oxygen, insurers will decline coverage for them. Newer modalities, such as noninvasive ventilation, may improve gas exchange and quality of life in some patients with hypercapnia and nocturnal oxygen desaturations, but subgroups of COPD patients who benefit have not been well-defined, and pending further investigation, guidelines for use should be considered tentative. Patients should be encouraged to enter a comprehensive rehabilitation program, but if one is unavailable or the patient declines, a rehabilitation approach should be applied. Practitioners should attempt to educate patients at each visit, offering advice not only on medications, but also on regular exercise, good nutrition, and ways of coping psychologically with chronic illness. By taking such a comprehensive and caring approach, and being available to assist with problems and crises, the practitioner can help to enhance the quality and length of the COPD patient's life.

Noninvasive PPV has been employed for decades in patients with chronic respiratory failure. Increasing use in patients with acute respiratory failure is a more recent phenomenon, mainly because of advances in noninvasive interfaces and ventilator modes. Noninvasive PPV delivered by nasal or oronasal mask has been demonstrated to reduce the need for endotracheal intubation, decrease lengths of stay in the ICU and hospital, and possibly reduce mortality. In the acute care setting, evidence now demonstrates the efficacy of noninvasive PPV for acute exacerbations of COPD, pulmonary edema, pulmonary contusions, and acute respiratory failure in patients who decline or who are not believed to be candidates for intubation. No firm conclusions can yet be made regarding patients with respiratory failure due to other causes, but studies suggest that noninvasive PPV may also be of benefit in patients with postoperative respiratory insufficiency, chest wall disease, and cystic fibrosis. Several factors are vital to the success of this therapy, including careful patient selection, properly timed intervention, a comfortable, well-fitting interface, patient coaching and encouragement, and careful monitoring. Noninvasive ventilation should be used as a way to avoid endotracheal intubation rather than as an alternative. Accordingly, a trial of noninvasive ventilation should be instituted in the course of acute respiratory failure before respiratory arrest is imminent, to provide ventilatory assistance while the factors responsible for the respiratory failure are aggressively treated. Moreover, the authors favor conservative management with expeditious intubation in patients who have other conditions that place them at risk during use of noninvasive ventilation or in patients failing to respond to noninvasive PPV. Noninvasive PPV clearly represents an important addition to the techniques available to manage patients with acute respiratory failure; however, because most studies have been retrospective and uncontrolled, many issues remain unresolved. Further controlled studies are needed to confirm the safety and efficacy of noninvasive PPV, evaluate the most appropriate selection of patients and timing of intervention, define the best type of interface, and assess the costs of noninvasive PPV in comparison with conventional therapy.

Negative pressure ventilation, the intermittent application of subatmospheric pressure around the chest and abdomen to assist breathing, is founded on sound physiological principles. As long as atmospheric pressure is maintained at the mouth and nose (and the upper airway remains patent), the negative peri-thoracic and -abdominal pressure increases the transpulmonary gradient, expanding the chest wall and lungs to assist inhalation. Exhalation is achieved mainly via passive recoil of the chest wall and lungs, although it is possible to assist this by imposing a supra-atmospheric peri-thoracic and -abdominal pressure, as was the case with the “iron lung” used by Corrado et al. 1, as described in the current issue of the European Respiratory Journal . In fact, negative pressure ventilation has a long and important history in the annals of mechanical ventilation, dating back to the 1800s, when the first tank-type negative pressure ventilator was described as a manually powered resuscitation device 2. The need for respiratory assist devices greatly increased during the polio epidemics of the first half of the 20th century, and the use of electrically powered “iron lungs”, such as that described by Drinker and Shaw 3, began to increase, becoming the main means of ventilatory support outside of the anaesthesia suite. These devices enclosed patients up to their necks in bulky, heavy metal chambers that limited access to patients for nursing care. Consequently, a number of smaller, more portable negative pressure devices were created, including the “cuirass” ventilator, which consisted of a rigid shell that was applied over the anterior chest and abdomen 4, and the “jacket” ventilator that consisted of a rigid cage suspended over the chest and abdomen that was placed within an impervious jacket 5. Both of these devices saw …

A variety of mechanical devices may be used to provide assistance when ventilation and cough are severely impaired by progressive respiratory weakness caused by neuromuscular disease. Traditionally, positive pressure ventilation via a tracheostomy has been used, but if upper airway function is adequate, a variety of noninvasive devices also may be considered. Although positive pressure ventilation is the preferred noninvasive mode for assisting ventilation, other modes may be selected depending on patient needs, preferences, and physical characteristics.

Direct evidence linking alkaloids found in endophyte-infected tall fescue forage with the livestock disorder known as fescue toxicosis is lacking. Physiologic effects of fescue toxicosis include reduced serum prolactin concentration in cattle. A monoclonal antibody specific to the lysergic moiety of ergot alkaloids was developed in mice after creating an immunogen by linking lysergol to human serum albumin. The antibody was specific to the lysergic moiety and, therefore, it cross-reacted with ergot alkaloids, lysergic acid, and lysergol. The antibody did not cross-react with alkaloid derivatives that had bromated or hydrogenated lysergic ring moieties. Fescue toxicosis conditions were elicited in yearling Angus steers by permitting them to graze endophyte-infected tall fescue containing650 micrograms/kg of ergovaline for 60 days. Passive immunization of steers by infusion of the monoclonal antibody increased serum prolactin concentration by 7 ng/ml, beginning immediately after infusion. Control steers did not respond to treatment with bovine serum albumin. Active immunization of yearling Angus heifers with immunogens containing lysergol or ergonovine linked to human serum albumin resulted in an antibody response.

Chronic hypoxia increases the total blood volume (TBV) and pulmonary arterial blood pressure (Ppa) and induces pulmonary vascular remodeling. The present study was undertaken to assess how the pulmonary blood volume (PBV) changes during hypoxia and the possible role of PBV in chronic hypoxic pulmonary hypertension. A novel method has been developed to measure the TBV, PBV, and Ppa in conscious rats. The method consists of chronic implantation of a loose ligature around the ascending aorta and pulmonary artery, so that when the ligature is drawn tightly, it traps the blood in the pulmonary vessels and left heart and simultaneously kills the rat. The pulmonary veins are then ligated to separate the left ventricular blood volume from the PBV. This surgical approach, together with chronic catheterization of the pulmonary artery and the use of 51Cr-labeled red blood cells, allows measurement of TBV, PBV, and Ppa. This method has been used to analyze the relationships between TBV and PBV and between Ppa or right ventricular hypertrophy and PBV in two rat strains with markedly different TBV and Ppa responses to chronic hypoxia. PBV per given lung weight did not increase and even decreased during hypoxia despite marked increases in TBV. There was a close correlation between Ppa or right ventricular hypertrophy and PBV in the two strains of chronically hypoxic animals, suggesting that a greater PBV plays a significant role in the development of severe chronic hypoxic pulmonary hypertension in the altitude-susceptible Hilltop rats.

Aneurysm is a permanent abnormal dilatation of an artery or ventricle resulting from localized structural weakness and stretching of the arterial or ventricular wall due to high transmural pressure. Aneurysms occur mainly in systemic arteries and, to a lesser extent, in the left ventricle.

Commercial tall fescue (Festuca arundinacea Shreb.) cultivars containing non-toxic endophytes (Neotyphodium coenophialum Glenn, Bacon, Hanlin) are available. Hence, seed testing objectives have changed to examining seed for viable endophyte. Seedling diseases occur during testing and this study compared effects of fungicides on endophyte infection of seedling plants. Endophyte-infected ‘Jesup’ tall fescue seed were planted into cell packs and grown in the greenhouse. Chloroneb (1,4-dichloro-2,5-dimethoxybenzene), terrazole (5-ethoxy-3-(trichoromethyl)-1,2,4-thiadiazole), and propiconazole (1-[[2-(2,4-dichlorophenyl)-4-propyl-1,3-dioxan-2yl]methyl]-1H-1,2,4-triazole) were applied weekly to plants beginning 7 d until 21 d post germination. In a second experiment, seedling plants received applications of Propiconazole at d 7, 14, 21 and all possible combinations. Seedling endophyte infection rates were higher when terrazole or chloroneb (83.1 and 78.1%, respectively) were applied compared with no fungicide (73.5%) or propiconazole (5.0%). Endophyte mortality was reduced but not eliminated when propiconazole application to seedling plants was delayed. Contact fungicides should be used to control seedling diseases when evaluating endophyte viability.

We assessed the effect of an endurance triathlon consisting successively of a 3.8-km swim, a 180-km bicycle ride, and a 42-km run on the forced expiratory spirogram, indices of inspiratory and expiratory muscle strength (PImax and PEmax), and maximal voluntary ventilation (MVV). Twelve male participants were recruited from competitors in the Cape Cod Endurance Triathlon and underwent studies on the afternoon before the event, after each segment, and on the following morning. Participants averaged 32.9 yr of age. All completed the triathlon with an average finishing time of 12 h 45 +/- 90 min. Following completion of the triathlon, statistically significant declines occurred in FVC (7.1%), FEV1 (8.4%), FEF25-75% (15.2%), and FEF50% (18.6%), but not in MVV. On the morning after the triathlon, only FEV1 remained significantly below baseline. PImax was not significantly reduced after the swim, but significant reductions did occur after the bicycle and running events (26% and 25%, respectively); full recovery had occurred by the following morning. PEmax did not change significantly. We conclude that vital capacity, flow rates at mid-lung volumes, and inspiratory muscle strength decline as a consequence of participation in a triathlon.

We analyzed metabolic parameters in 11 volunteers after each segment of an endurance triathlon and, in a separate year, analyzed similar parameters in eight volunteers during 6 d of recovery following completion of an endurance triathlon. After the 2.4-mile ocean swim, serum lactate tripled, and albumin and muscle enzymes were increased. After the 112-mile bicycle ride, mild dehydration occurred, and muscle enzymes and uric acid levels increased markedly. Serum lactate was elevated over baseline but was lower then after the swim. After the 26.2-mile run, dehydration and muscle damage progressed; serum triglycerides dropped by 50%. Serum lactate remained elevated, but less than after either of the other segments. During recovery, muscle enzymes continued to rise and peaked (creatine phosphokinase on the day following the triathlon at 4920 +/- 685 U.ml-1; range 1321-16,746); creatine phosphokinase and lactate dehydrogenase remained significantly elevated at the end of the recovery period. Total protein and albumin decreased, suggesting alterations in their synthesis or their utilization for tissue repair. Serum cholesterol levels fell significantly until the 4th d. Serum triglycerides slowly increased to baseline over 4 d, suggesting their use as energy substrate during recovery. Thus, competition in an endurance triathlon causes skeletal muscle injury that appears early, increases as the triathlon progresses, and is still apparent even 6 d after completion of the triathlon. Changes in plasma proteins and lipid suggest that energy substrate utilization is shifted as the triathlon progresses and as the body repairs itself following completion of the event.

Cor pulmonale is an important consequence of COPD. Although the incidence is not precisely known, it is seen more frequently in patients with hypoxemia, CO2 retention and severely reduced FEV1. When present, it limits peripheral oxygen delivery, increases shortness of breath, and reduces exercise endurance. It is also associated with higher mortality rates independent of other prognostic variables. Numerous factors may contribute to the development of cor pulmonale in patients with COPD, but its primary cause is chronic alveolar hypoxia resulting in pulmonary vasoconstriction, vascular remodeling and pulmonary hypertension. The physical exam, chest radiograph and ECG may be helpful in detecting the presence of cor pulmonale, but because of anatomic changes that occur in the chest, these tests are often insensitive in patients with COPD. Noninvasive diagnostic techniques utilizing Doppler echocardiography and radionuclide angiography allow for detection of RV dysfunction at an earlier stage and in most cases, preclude the need for right heart catheterization. LTO2 is the only therapy shown to improve survival in patients with COPD. However, statistical proof correlating improvements in pulmonary hemodynamics with increased survival is lacking. Bronchodilators, such as the beta 2 agonists and especially theophylline, may have beneficial effects on pulmonary hemodynamics in addition to their effect on respiratory function and are useful in COPD when RV dysfunction is present. Diuretics and phlebotomy are also useful in improving symptoms in appropriate patients. Vasodilators such as calcium channel blockers and ACE-inhibitors may improve pulmonary hemodynamics acutely, but may lower arterial PO2 by worsening ventilation-perfusion matching or blunt the improvement in pulmonary hemodynamics seen with supplemental oxygen. The long-term benefits of these agents have not been proven and their routine use in patients with cor pulmonale due to COPD cannot be recommended.