Plasma Creatine Kinase Activity Research Articles

Effects of Preconditioning Lower-Extremity Resistance Exercises on Multidirectional Repeated Sprinting-Induced Muscle Damage.

Hsu, SM, Tseng, WC, Chiu, CH, Hsieh, TY, Weng, MC, Dai, X, and Chen, CH. Effects of preconditioning lower-extremity resistance exercises on multi directional repeated sprinting-induced muscle damage. J Strength Cond Res XX(X): 000-000, 2024-Sprint exercise-induced muscle damage is a popular area of investigation. To examine whether preconditioning lower-extremity resistance exercises would reduce the amount of muscle damage observed after a multi-directional repeated sprinting (MDS) exercise. Thirty-six elite male athletes were randomly allocated to 1 of 3 groups: general warm-up (GW), GW with loaded jump squat (SQ), and GW with loaded hip thrust (HT). Knee flexion isometric strength (MVIC), passive hip flexion range of motion (ROM), soreness, countermovement jump (CMJ), sprint time, and plasma creatine kinase (CK) activity were measured at the pretest and post-24, -48, and -72 hours of the MDS. For SQ, the CK at post-72 hours was significantly lower than the GW group. The decrements of MVIC at post-48 and -72 hours for SQ were significantly less than the GW group. The CMJs at post-24 and -48 hours for SQ and at post-48 and -72 hours for HT were significantly higher than the GW group. The 0-10 m sprint time at post-48 hour for HT was significantly better than the GW group. Adding the SQ or HT interventions to a GW before MDS has a protective effect on the sprinting-induced muscle damage and faster recovery.

Effects of far-infrared radiation lamp therapy on recovery from a simulated soccer-match in elite female soccer players.

We investigated the effects of far-infrared radiation (FIR) lamp therapy on changes in muscle damage and performance parameters following six sets of 15-min Loughborough intermittent shuttle test (LIST), a simulated soccer match. Twenty-four elite female soccer players (20-24 y) were assigned into FIR or sham treatment group (n = 12/group). The participants received a 60-min FIR or sham treatment (30 min per muscle) over knee extensors (KE) and flexors (KF) at 2, 25, 49, 73, and 97 h post-LIST. Maximal voluntary isometric contraction (MVC) torque and muscle soreness of the KE and KF, plasma creatine kinase (CK) activity as muscle damage markers, and several performance parameters including countermovement jump (CMJ) and Yo-Yo intermittent recovery test level 1 (YYIR1) were measured before and 1, 24, 48, 72, 96, and 120 h post-LIST. Changes in the measures were compared between groups by a mixed-design two-way ANOVA. The running distance covered during LIST and changes in the measures at 1-h post-LIST (before the treatment) were similar (p = 0.118-0.371) between groups. Changes in muscle damage markers at 24-120 h post-LIST were smaller (p < 0.05, η2 = 0.208-0.467) for the FIR (e.g., MVC-KE torque decrease at 48-h post-LIST: -1 ± 2%, peak KE soreness: 16 ± 10 mm, peak CK: 172 ± 42 IU/L) than sham group (-11 ± 9%, 33 ± 7 mm, 466 ± 220 IU/L, respectively). Performance parameters recovered faster (p < 0.05, η2 = 0.142-0.308) to baseline for the FIR (e.g., decreases at 48-h post-LIST; CMJ: 0 ± 1%, YYIR1: 0 ± 1%) than sham group (-6 ± 2%, -9 ± 6%, respectively). These results suggest that the FIR lamp therapy was effective for enhancing recovery from a soccer match.

Ecotoxicological Assessment of Ponds Contaminated by Wastewater of Livestock Enterprises by Fish Biomarkers

The morphometric characteristics of internal organs, the morphological composition of blood, and indicators of metabolic processes in the blood plasma and hepatopancreas of the two-year-old carp (&lt;i&gt;Cyprinus carpio&lt;/i&gt; L.) from the conditionally clean pond and contaminated with sewage from a livestock enterprise pond were examined. It was established that the considered contamination caused increase of the spleen mass and its index respectively 1.63 and 1.65 times, but did not affect live weight, body length and height, body structure index, hepatopancreas mass and its index. The hemoglobin concentration, number of erythrocytes, thrombocytes and monocytes in blood of carps from the contaminated pond was lower than in control, whereas number of the segmented neutrophils and ESR were higher, and the number of leukocytes, eosinophils, lymphocytes and rod-nucleated neutrophils did not differ. Wastewater from the livestock enterprise affected metabolic processes in carp, particularly caused increase of the glucose and total protein concentration, the lactate dehydrogenase, aspartate aminotransferase and creatine kinase activity in blood plasma and hepatopancreas. At the same time, there were no differences between specimens from the conditionally clean and contaminated pond in terms of content of triglycerols, cholesterol, urea, creatinine, calcium, inorganic phosphorus, AlAT and AsAt activity in blood plasma and hepatopancreas and total protein content and LHD activity in hepatopancreas, content of total protein, glucose, creatinine, urea, the glucose content in hepatopancreas. The established changes in internal organs, morphological composition of blood and metabolic parameters, particularly concentration of hemoglobin and the erythrocytes number in blood, glucose and total protein content, and activity of lactate dehydrogenase and creatine kinase in carp enabled to propose to use these parameters as supplementary over assessment of the ecotoxicological state of ponds contaminated by wastewater from livestock enterprises.

High-Temperature Stress Induces Autophagy in Rainbow Trout Skeletal Muscle

Ectothermic animals, such as teleosts, have increasingly been exposed to stressful high-temperature events due to global warming. Currently, the effects of thermal stress on skeletal muscle, a key tissue for fish growth, are unknown. This study examined the impact of high-temperature stress on the skeletal muscle transcriptome of rainbow trout (Oncorhynchus mykiss) in control (15 °C) and high-temperature (20 °C) conditions. Additionally, we examined the plasmatic levels of cortisol, glucose, and creatine kinase activity, and examined oxidative damage and autophagy activation in skeletal muscle. High-temperature stress induced significant increases in cortisol and glucose plasmatic levels. Nevertheless, no changes were observed in creatine kinase activity in plasma and skeletal muscle oxidation. Skeletal muscle RNA was isolated and sequenced using the HiSeq Illumina platform. A total of 383,796,290 reads were mapped onto the reference rainbow trout genome. The transcriptomic analysis showed that 293 genes were upregulated in the high-temperature group, mainly associated with autophagosome assembly, amino acid transport, and the glutamine metabolic process. On the other hand, 119 genes were downregulated in the high-temperature group, mainly associated with digestion, proteolysis, and the muscle contraction process. In addition, RT-qPCR of differentially expressed representative genes and Western blot analysis of LC3-II/LC3-I levels confirmed skeletal muscle autophagy induced by high temperature. This study sheds light on intriguing facets of the adaptive response of rainbow trout skeletal muscle to high-temperature stress and provides significant insights into the physiology of autophagy in teleosts.

Plasma Creatine Kinase and Aspartate Aminotransferase Activities Before, During, and After 5 Days of Intramuscular Penicillin Administration in Sedentary Horses.

Muscle damage can result in leakage of intracellular enzymes such as creatine kinase (CK) and aspartate transaminase (AST) into plasma. There are no controlled documentations of the effects of intramuscular antibiotic drug administration on plasma CK and AST activities in horses. The objective of this experiment was to test the hypothesis that 5 days of intramuscular procaine penicillin G injection in normal horses would result in increased plasma activities of CK and AST. Nine healthy adult horses were sampled for 7 days preceding, 5 days during, and 32 days following procaine penicillin G (22,000 IU/kg) administration intramuscularly twice daily. Heparinized jugular venous blood samples were obtained daily before treatment and were analyzed the same day for plasma activities of CK and AST. Repeated measures ANOVA and post hoc Tukey's Test were used to identify days where CK or AST were elevated compared to control means at a significance level of P < .05. Beginning the day after first injection, plasma CK increased above the reference range, peaking at 2,046 ± 627 U/L after 3 days, and returned to 227 ± 57.3 U/L (within the reference range) 9 days after treatment began. Beginning the day after first injection, plasma AST increased, peaking at 703 ± 135 U/L on the day after the last injection. Plasma AST did not return to the reference range in all individual horses until 29 days after the last injection (mean 247 ± 33 U/L). Compared to the control period, plasma CK and AST elevations lasted for 8 and 28 days, respectively, after the onset of treatment (P < .001 to P=.03) and lasted for 4 and 24 days, respectively, after the last day of treatment (P < .001 to P=.03).

Effects of far-infrared radiation lamp therapy on recovery from muscle damage induced by eccentric exercise

ABSTRACT The present study investigated the effects of a far-infrared radiation (FIR) lamp therapy on changes in muscle damage and proprioception markers after maximal eccentric exercise of the elbow flexors (EF: Study 1) and the knee flexors (KF: Study 2) in comparison to a sham treatment condition. In each study, 24 healthy sedentary women were assigned to a FIR or a sham treatment group (n = 12/group). They performed 72 maximal EF eccentric contractions (Study 1) or 100 maximal KF eccentric contractions (Study 2) with their non-dominant limbs. They received a 30-min FIR (wavelength: 8–14 µm) or sham treatment at 1, 25, 49, 73 and 97 h post-exercise to the exercised muscles. Maximum voluntary isometric contraction (MVC) torque, muscle soreness, plasma creatine kinase activity, and proprioception assessed by position sense, joint reaction angle, and force match were measured before, and 0.5, 24, 48, 72, 96 and 120 h post-exercise. The outcome measures showed significant changes (P < 0.05) at 0.5-hour post-exercise (before treatment) similarly (P > 0.05) between the conditions in both studies. However, changes in all measures at 24–120 h post-exercise were smaller (P < 0.05) for the FIR than sham condition in both studies. For example, MVC torque returned to the baseline by 72 h post-exercise for the FIR condition in both studies, but was still 19 ± 6% (Study 1) or 17 ± 12% (Study 2) lower than the baseline at 120 h post-exercise for the sham condition. These results suggested that the FIR lamp therapy was effective for accelerating recovery from muscle damage.

Effects of Unilateral Eccentric versus Concentric Training of Non-Immobilized Arm During Immobilization.

The present study tested the hypothesis that eccentric training (ET) of non-immobilized arm would attenuate negative effects of immobilization and provide greater protective effects against muscle damage induced by eccentric exercise after immobilization, when compared with concentric training (CT). Sedentary young men were placed to ET, CT or control group (n = 12/group), and their non-dominant arms were immobilized for 3 weeks. During the immobilization period, ET and CT groups performed 5 sets of 6 dumbbell curl eccentric-only and concentric-only contractions, respectively at 20-80% of maximal voluntary isometric contraction (MVCiso) strength over six sessions. MVCiso torque, root-mean square (RMS) of electromyographic activity during MVCiso, and bicep brachii muscle cross-sectional area (CSA) were measured before and after immobilization for both arms. All participants performed 30 eccentric contractions of the elbow flexors (30EC) by the immobilized arm after the cast was removed. Several indirect muscle damage markers were measured before, immediately after, and for 5 days following 30EC. ET increased MVCiso (17 ± 7%), RMS (24 ± 8%), and CSA (9 ± 2%) greater (P < 0.05) than CT (6 ± 4%, 9 ± 4%, 3 ± 2%) for the trained arm. The control group showed decreases in MVCiso (-17 ± 2%), RMS (-26 ± 6%), and CSA (-12 ± 3%) for the immobilized arm, but these changes were attenuated greater (P < 0.05) by ET (3 ± 3%, -0.1 ± 2%, 0.1 ± 0.3%) than CT (-4 ± 2%, -4 ± 2%, -1.3 ± 0.4%). Changes in all muscle damage markers after 30EC were smaller (P < 0.05) for the ET and CT than control, and ET than CT group (e.g., peak plasma creatine kinase activity, ET: 860 ± 688, CT: 2,390 ± 1104, control: 7,819 ± 4,011 IU/L). These results showed that ET of the non-immobilized arm was effective for eliminating the negative effects of immobilization and attenuating eccentric exercise-induced muscle damage after immobilization.

Hydrolyzed whey protein enriched with glutamine dipeptide attenuates skeletal muscle damage and improves physical exhaustion test performance in triathletes.

To investigate the effects of hydrolyzed whey protein enriched with glutamine dipeptide on the percentage of oxygen consumption, second ventilatory threshold, duration and total distance covered, and skeletal muscle damage during an exhaustion test in elite triathletes. The study was a randomized, double-blinded, placebo-controlled, crossover trial. Nine male triathletes performed a progressive incremental test on a treadmill ergometer (1.4 km h-1·3 min-1) 30 min after ingesting either 50 g of maltodextrin plus four tablets of 700 mg hydrolyzed whey protein enriched with 175 mg of glutamine dipeptide diluted in 250 ml of water (MGln) or four tablets of 700 mg maltodextrin plus 50 g maltodextrin diluted in 250 ml of water (M). Each athlete was submitted to the two dietary treatments and two corresponding exhaustive physical tests with an interval of one week between the interventions. The effects of the two treatments were then compared within the same athlete. Maximal oxygen consumption, percentage of maximal oxygen consumption, second ventilatory threshold, and duration and total distance covered were measured during the exhaustion test. Blood was collected before and immediately after the test for the determination of plasma lactate dehydrogenase (LDH) and creatine kinase (CK) activities and lactate concentration (also measured 6, 10, and 15 min after the test). Plasma cytokines (IL-6, IL-1β, TNF-α, IL-8, IL-10, and IL-1ra) and C-reactive protein levels were also measured. A single dose of MGln increased the percentage of maximal oxygen consumption, second ventilatory threshold duration, and total distance covered during the exhaustion test and augmented plasma lactate levels 6 and 15 min after the test. MGln also decreased plasma LDH and CK activities indicating muscle damage protection. Plasma cytokine and C-reactive protein levels did not change across the study periods. Conditions including overnight fasting and a single dose of MGln supplementation resulted in exercising at a higher percentage of maximal oxygen consumption, a higher second ventilatory threshold, blood lactate levels, and reductions in plasma markers of muscle damage during an exhaustion test in elite triathletes. These findings support oral glutamine supplementation's efficacy in triathletes, but further studies require.

Effects of Eurycoma longifolia Jack supplementation on eccentric leg press exercise-induced muscle damage in rugby players.

Eurycoma longifolia Jack (ELJ) is a herbal plant that has androgenic and antioxidant effects. We investigated the short-term effect of ELJ supplementation on muscle damage induced by eccentric exercise. Eighteen young (19-25 years), well-trained rugby 7s players were assigned to an ELJ or a placebo (PLA) group (n = 9/group). Each participant took four 100-mg capsules a day for seven days prior to performing a leg press eccentric exercise to failure in a double-blind fashion. Peak force, peak power and jump height in countermovement jump (CMJ), drop jump reactive strength index (RSI), muscle soreness assessed by a 100-mm visual analogue scale, plasma creatine kinase (CK) activity, and salivary hormones were measured at 24 h before and 0.5, 24, 48, 72, and 96 h after the exercise. Changes in the variables over time were compared between the groups by two-factor mixed-design ANOVA. The number of eccentric contractions performed was similar (P = 0.984) between the ELJ (21 ± 5) and PLA groups (21 ± 5). Salivary testosterone and cortisol concentrations did not change (P > 0.05) after the supplementation for both groups. CMJ peak power (-9.4 ± 5.6%) and height (-10.6 ± 4.9%), and RSI (-15.2 ± 16.2%) decreased at 24 h after exercise (P < 0.05), and muscle soreness (peak: 89 ±10 mm) and plasma CK activity (peak: 739 ± 420 IU/L) increased after exercise (P < 0.05) without significant differences between groups. These results showed that 7-day ELJ supplementation prior to the leg press eccentric exercise had no significant effects on hormones, performance and muscle damage markers for the athletes.

Effect of training load on sleep parameters and biochemical fatigue markers in elite swimmers.

The effect of strenuous exercise on sleep patterns in swimmers is equivocal. Therefore, the purpose of the study was to describe possible changes in sleep parameters among elite swimmers subjected to different training loads (TL). Methods: Eighteen elite swimmers (8 females) were monitored across two high-volume preparatory 1-wk periods (P1, P2) and a lower-volume tapering 1-wk period (P3) before a major competition. Internal (the session rating of perceived exertion [sRPE]) and external TL (training duration and volume) were measured, along with several sleep indices (e.g., bedtime, get-up time, sleep time, wake after sleep onset [WASO]). Serum measurements of urea, creatine kinase (CK), testosterone and cortisol were taken before and after training sessions at the beginning (Mondays) and end (Fridays) of each micro cycle. Athlete TL decreased significantly in a stepwise manner from P1 to P2 and from P2 to P3. Of all sleep parameters, only significant differences in bedtime and get-up time emerged (P3 > P1 and/or P2). Sleep duration (~6.3 h) or quality (WASO: 41-45 min) were also unaffected by TL. CK levels declined from P1 to P3 (d = -0.8), and from P2 to P3 (d = -0.6). Positive exercise-induced changes in CK were also seen in each training period. The other biomarkers did not show the same temporal or acute patterns. Irrespective of the TL, the monitored swimmers experienced insufficient and fragmented sleep across this study. Neither sleep quality nor quantity were affected by different magnitudes of TL. Among the biochemical markers of fatigue, baseline plasma CK activity best reflected the physiological response to TL.

Assessment of Seminal Plasma Creatine Kinase Activity and Malondialdehyde Concentration among Normozoospermia but Infertile Men

Background: Despite the considerable research efforts that have been made by Reproductive Biologists to understand the etiologies of male infertility, idiopathic male factor infertility still remains unexplained. It occurs in about 10% cases of infertility. Since the etiologies cannot be identified using routine semen analysis, it is important to identify cellular and sub-cellular sperm complications that may help to explain the cause(s) of the infertility, thus stimulate caregivers to direct the further work-up, diagnosis and counseling of affected individuals. The objective of this study was to determine seminal plasma creatine kinase (CK) activity and malondialdehyde (MDA) concentration among normozoospermia but infertile males. Materials and Methods: After routine semen analysis, seminal plasma CK activity and MDA were determined among 75 normozoospermia but infertile men and 50 men of proven fertility using spectrophotometric method. Unpaired Students-t-test and regression analysis were used to compare and associate CK activity and MDA concentration with sperm characteristics. Results: Significantly higher (p&lt;0.001) level of MDA and CK activity were observed among infertile subjects than control group. Sperm count, percent motility, and viability were significantly lower (p&lt;0.05) among study participants than control subjects. Similarly, percentage abnormal morphology was significantly higher (p&lt;0.05) among infertile subjects than control group. The Odds of elevated CK activity to impair sperm motility, viability and morphology were 9.12(CI 102.6, 318.3), 3.18 (CI 129.9, 170.8) and 1.9 (CI 192.2, 208.1) times respectively higher among infertile group than controls. Similarly, the Odds of higher levels of MDA to impair sperm cell motility, viability and morphology were 5.02(CI 2.14, 4.6), 2.26(CI 2.34, 3.64) and 2.9 (CI 2.12, 3.73) times respectively higher among infertile group than control subjects. Conclusions: The seminal plasma CK activity and MDA constitute good indicators of functional metabolic activity and fertility potentials of spermatozoa among subjects with unexplained infertility.

Lifetime prevalence and correlates of syncope in five ancestry groups. The HELIUS study.

To explore the lifetime prevalence and correlates of syncope in the general population. Through stratified random sampling, we included 14,937 White-European, Asian, Turkish, Moroccan, and West-African ancestry adults (18-70 y) in the cross-sectional Healthy Life in an Urban Setting (HELIUS) population study. We assessed syncope history by ancestry, and the potential correlates body mass index (BMI), systolic/diastolic blood pressure (SBP/DBP), resting plasma activity of creatine kinase (CK), the ATP-generating enzyme that facilitates cardiovascular contractility and sodium retention, and in a subgroup, supine cardiac contractility (dP/dt), cardiac output (CO) and systemic vascular resistance (SVR). Mean age of the participants (39% men) was 43.3 y (SD12.9). Lifetime prevalence of syncope in women/men was respectively (%), White-European 42/24; Asian 34/19; Moroccan 32/16; Turkish 30/17; and West-African 20/14. Mean age at first syncope was 24 y (SD13). Participants with syncope history had lower SBP, DBP, BMI, CK, and modestly lower dP/dt and CO, but not SVR. In multivariable regression analysis, male sex (OR 0.52 [0.48 to 0.57]), West-African ancestry (0.59 [0.54 to 0.65]), and CK (0.56 [0.46 to 0.69]/log CK increase) were negatively associated with syncope. This study indicates that West-African ancestry, male sex, and high activity of the pressor enzyme CK are associated with lower syncope prevalence. These findings may inform further studies on the hemodynamics of syncope.

Effects of Crude Rice Bran Oil and a Flaxseed Oil Blend in Young Horses Engaged in a Training Program.

Rice bran oil and flaxseed oil contain omega-3 fatty acids with the potential to reduce post-exercise inflammation and muscle damage. This study measures plasma interleukin-1β and creatine kinase and fatty acid profiles in lightly worked, young horses (Equus caballus) undergoing an exercise test after 60 days (d) of oil consumption, where the oil replaced 25% of concentrate calories. Treatments consisted of CON (no oil), FLAX (flaxseed oil blend), and RICE (crude rice bran oil). Blood was collected pre-exercise, and again at 1 min, 30 min, 24 h, 48 h, and 72 h post-IET. Data were analyzed by repeated measures ANOVA. Plasma creatine kinase activity was not different in CON during the study, greater (p &lt; 0.05) in RICE from pre-exercise to 30 min post-exercise across all exercise tests, and lesser (p &lt; 0.05) in FLAX at 30 min post-exercise on d 30 compared to d 0. Plasma interleukin-1β was greater (p &lt; 0.01) in CON on d 60, but no differences were observed in FLAX and RICE throughout the study. Plasma alpha-linolenic and linoleic acids were greatest (p &lt; 0.05) in FLAX after 30 d of inclusion, while CON horses had greater (p &lt; 0.05) EPA across all exercise tests and DHA after 60 d. These results indicate that 60 d of inclusion of crude rice bran oil or a flaxseed oil blend may benefit lightly worked, young horses by reducing training-program-related increases in interleukin-1β, while a flaxseed oil blend may reduce exercise-induced increases in creatine kinase. Additionally, the flaxseed oil blend has the potential to increase plasma omega-3 and omega-6 fatty acids. Replacing 25% of concentrate calories with flaxseed or rice bran oil has potential benefits for young horses in training.

Effects of Far-Infrared Radiation-Lamp Therapy on Recovery From Simulated Soccer Match Running Activities in Elite Soccer Players.

The authors investigated whether far-infrared radiation (FIR) lamp therapy would reduce muscle damage and enhance recovery from multiple soccer-match-related running activities. Twenty-four elite female soccer players (20-24y) were assigned into a FIR or a sham treatment group (n = 12/group). They performed a daily 90-minute Loughborough Intermittent Shuttle Test (LIST) for 6 consecutive days. Maximal voluntary contraction torque of the knee extensors (KEs) and flexors, muscle soreness, plasma creatine kinase activity, countermovement jump, and several other performance measures (eg,30-m dash, Yo-Yo Intermittent Recovery Test Level 1) were taken before the first LIST, 1 hour after each LIST, and 24, 48, 72, 96, and 120hours after the last LIST. All participants received a 30-minute FIR or sham treatment on KEs and knee flexors, respectively, at 2 hour after each LIST and 25, 49, 73, and 97hours after the last LIST. All measures changed significantly (P < .05) at 1 hour after the first LIST without difference (P > .05) between groups. Maximal voluntary contraction torque (eg,the largest decrease of KE for FIR: 13% [4%], sham: 25% [5%]), countermovement jump height (4% [3%] vs 14% [4%]), and other performance measures (eg,Yo-Yo Intermittent Recovery Test: 11% [5%] vs 26% [5%]) decreased less, and peak muscle soreness (eg,KE: 26 [9] vs 51 [18]mm) and plasma creatine kinase activity (172 [32] vs 1289 [610] IU/L) were smaller for the FIR than for the sham group (P < .05), and they returned to the baseline earlier (P < .05) for the FIR group. These results suggest that the FIR therapy provided potent effects on reducing accumulated muscle damage and enhancing recovery.

Intrageneric cross-reactivity of monospecific rabbit antisera against venoms of the medically most important Bitis spp. and Echis spp. African snakes.

BackgroundSnakebite envenomation exerts a heavy toll in sub-Saharan Africa. The design and production of effective polyspecific antivenoms for this region demand a better understanding of the immunological characteristics of the different venoms from the most medically important snakes, to select the most appropriate venom combinations for generating antivenoms of wide neutralizing scope. Bitis spp. and Echis spp. represent the most important viperid snake genera in Africa.Methodology/Principal findingsEight rabbit-derived monospecific antisera were raised against the venoms of four species of Bitis spp. and four species of Echis spp. The effects of immunization in the rabbits were assessed, as well as the development of antibody titers, as judged by immunochemical assays and neutralization of lethal, hemorrhagic, and in vitro coagulant effects. At the end of immunizations, local and pulmonary hemorrhage, together with slight increments in the plasma activity of creatine kinase (CK), were observed owing to the action of hemorrhagic and myotoxic venom components. Immunologic analyses revealed a considerable extent of cross-reactivity of monospecific antisera against heterologous venoms within each genus, although some antisera provided a more extensive cross-reactivity than others. The venoms that generated antisera with the broadest coverage were those of Bitis gabonica and B. rhinoceros within Bitis spp. and Echis leucogaster within Echis spp.Conclusions/SignificanceThe methodology followed in this study provides a rational basis for the selection of the best combination of venoms for generating antivenoms of high cross-reactivity against viperid venoms in sub-Saharan Africa. Results suggest that the venoms of B. gabonica, B. rhinoceros, and E. leucogaster generate antisera with the broadest cross-reactivity within their genera. These experimental results in rabbits need to be translated to large animals used in antivenom production to assess whether these predictions are reproduced in horses or sheep.

Creatine Kinase and Myoglobin Plasma Levels in Mountain Bike and Road Cyclists 1 h after the Race

The aim of this study was to determine if 1 h after a cycling race, changes in plasma creatine kinase activity (CK) and myoglobin concentrations (MB) differ between mountain bike and road cyclists and if these changes show any correlation with race performance. Male mountain bike cyclists (n = 11) under 23 years old and male road cyclists (n = 14), also under 23 years old, were studied following one of their respective races. The cyclists had blood drawn 2 h before and 1 h after the race to assess CK and MB, then the change in pre- and post-race difference was calculated (ΔCK and ΔMB). Each cyclist’s performance time was recorded and the time difference from the winner was calculated (TD). The cyclists’ aerobic capacity was assessed during the incremental test, which determines maximal oxygen uptake and maximal aerobic power. It was observed that 1 h after the cycling race, CK (p = 0.001, η2 = 0.40, F = 15.6) and MB (p = 0.000, η2 = 0.43, F = 17.2) increased, compared to pre-race values. Post-race CK increased only in road cyclists, while post-race MB increased only in mountain bike cyclists. Smaller TD were found for lower ΔMB in road cyclists but for higher ΔCK in mountain bike cyclists.

Pharmacokinetics and bioavailability of carprofen in sheep.

The aim of this study was to determine the pharmacokinetics and bioavailability of carprofen in sheep following single intravenous (IV), intramuscular (IM), subcutaneous (SC), and oral (PO) administrations of a parenteral formulation at a dose of 4mg/kg. A total of eight sheep were used for the investigation. The study comprised four periods, according to a crossover design with a 21-day washout period between treatments. Plasma concentrations of carprofen were measured using HPLC-UV. Pharmacokinetic parameters were estimated by non-compartmental model analysis. Following IV administration, t1/2ʎz , ClT , and Vdss were 43.36 h, 1.98 ml/h/kg, and 121.36 ml/kg, respectively. The Cmax(obs) was 26.57 mg/ml for the IM, 23.76 mg/ml for the SC, and 15.90 mg/ml for the PO. The bioavailability following IM, SC, and PO administrations was 75.47%, 82.00%, and 62.51%, respectively. Plasma creatine kinase activity increased significantly at 3, 6, and 12 h following IM administration of carprofen. Despite differences in plasma concentrations and bioavailability among administration routes, carprofen at 4mg/kg dose may provide the plasma concentration (>1.5μg/ml) needed for analgesic effect during 144 h in all routes. However, because of the slow absorption rate after SC and PO routes, the IV route may be preferred primarily for the rapid onset in the analgesic and anti-inflammatory effect of carprofen in sheep. Despite the favorable kinetics, the muscle damage caused by IM injection limits use of carprofen via IM route.

Influence of dietary supplemental guanidinoacetic acid on performance, haematological parameters, carcass characteristics and enzyme activities in male broilers with cold-induced ascites

ABSTRACT This study aimed to evaluate the effects of dietary guanidinoacetic acid (GAA) on performance, enzyme activity and biochemical variables of broilers with cold-induced ascites. A total of 640 day-old male broiler chicks (Cobb 500) were randomly assigned to four treatments (with 8 replicates of 20 birds) including a control and diets supplemented with 0.6, 1.2 and 1.8 g of GAA per kg of feed. On day 14, the temperature was reduced to 17°C during the daytime and 14°C at night. Dietary inclusion of 0.6 g/kg GAA decreased BWG in compared to those fed other levels in the grower period (P < 0.05). The ratio of right to total ventricle, mortality and relative weights of liver were lower in birds fed the diet with 1.2 g/kg GAA compared to bids fed other levels (P < 0.05). The plasma activity of creatine kinase (CK) increased in the birds fed with 1.2 and 1.8 g/kg GAA compared to chicks fed the control diet. It can be concluded that dietary supplemental 1.2 g/kg GAA would be a beneficial way to decrease the mortality rate of broiler reared under cold stress conditions. In addition, the blood levels of HDL-C increased in broilers fed the 1.2 g/kg GAA diet.

Changes in Insulin Sensitivity and Lipid Profile Markers Following Initial and Secondary Bouts of Multiple Eccentric Exercises.

An acute bout of eccentric exercise affects insulin sensitivity and lipid profile, but how the magnitude of muscle damage affects them is not clear. We compared changes in blood insulin sensitivity and lipid markers after the first (EC1) and second (EC2) eccentric exercise bouts. Fifteen sedentary young men performed arm, leg and trunk muscle eccentric exercises, and repeated them 2 weeks later. Fasting blood samples were taken before, 2 h and 1–5 days after each exercise bout to analyze plasma creatine kinase (CK) activity, serum glucose (GLU), insulin, homeostasis model assessment (HOMA), triacylglycerols (TG), total (TC) and low- (LDLC) and high-density lipoprotein cholesterol (HDLC) concentrations as well as TC/HDLC ratio. Changes in these measures were compared between bouts and relationships to peak plasma CK activity were analyzed. Plasma CK activity increased (p < 0.05) after EC1 (peak: 101,668 ± 58,955 IU/L) but not after EC2. The magnitude of changes in GLU (peak after EC1: 26 ± 10% vs. EC2: 7 ± 6%), insulin (46 ± 27% vs. 15 ± 8%), HOMA (86 ± 48% vs. 24 ± 15%), TC (−20 ± 5% vs. −6 ± 4%), TG (−32 ± 11% vs. −6 ± 3%), LDHC (−47 ± 15% vs. −12 ± 9%), HDLC (35 ± 26% vs. 7 ± 4%), and TC/HDLC ratio (−139 ± 13% vs. −11 ± 7%) were significantly greater after EC1 than EC2. Peak plasma CK activity was significantly (p < 0.05) correlated with the peak changes in blood insulin sensitivity and lipid markers for the combined data of EC1 and EC2. These results suggest that the greater the magnitude of muscle damage, the greater the magnitude of changes in the insulin sensitivity to a negative direction and lipid markers to a positive direction.

Treatment, clinical course and outcome of tibial neuropathy in German Holstein cows

As a follow-up to a previous study on the incidence, history and clinical findings of tibial neuropathy (TN), the present work aimed at describing the treatment and prognosis of this disease. Of 88 German Holstein dairy cows with unilateral (UTN, n = 71) or bilateral (BTN, n = 17) TN, 68 (56 UTN, 12 BTN) with a complete data set were analyzed. They were retrospectively assigned to one of four groups: no treatment - spontaneous healing within 48 h (Spontaneous, 5 UTN), no bandage (0Cast, 8 UTN, 3 BTN) or treatment with anti-inflammatory drugs and support bandage (StV, 3 UTN) or fiberglass cast (Cast, 40 UTN, 9 BTN). Treated cows were re-examined five times (14, 21, 28, 42 and 56 days after the first presentation). The plasma activity of creatine kinase was measured at the last re-examination in 29 cows similar to measurement at day 0. The observed overall success rate of treatment of cows with UTN was considerably higher compared with untreated cows (Cast 98 % and StV 100 % vs. 0Cast 62 %). By comparison, the observed difference between treated and untreated cows with BTN was not so clear (78 % vs. 67 %). Recovering cows exhibited a calculated longer median survival time than cows that did not recover (545 d vs. 100 d). Plasma creatine kinase activities were increased initially and returned within the reference interval (434 U/l and 152 U/L) following treatment. Cows with ETN have an excellent prognosis provided that treatment with anti-inflammatory drugs and stabilizing bandage is administered. In cows with BTN, the prognosis depended on the type and degree of the primary injury. Loss of skin sensitivity indicated a poor prognosis. From an economic standpoint, treatment of TN is indicated provided that the prognosis is good. In cows that had healed clinically, the average survival time extended into the following lactation. This study highlights the advantages of a support bandage for the treatment of cows with TN. Compared with other peripheral neuropathies, muscle damage appears to be of particular importance in TN.