Biochemical composition of blood plasma and follicular fluid in relation to follicular size in buffalo

The aim of this study was to examine the biochemical composition of follicular fluid from different-sized follicles and its relationship with that of blood plasma in buffalo. Ovaries of adult and healthy buffaloes were collected after slaughter. Follicular fluid was aspirated from three size classes of follicles (4–5, 6–9, and 10–20 mm diameter). Blood samples were also collected from these buffaloes immediately before slaughter. The follicular fluid and blood plasma samples were analyzed for metabolites (glucose, total protein, albumin, globulin, cholesterol, triglycerides, urea, and creatinine), ions (calcium and phosphorus), and enzymes (alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase). The follicular fluid calcium, urea, creatinine, albumin, and ASAT and ALAT concentrations were not affected by the size of the ovarian follicles. Follicular fluid concentrations of phosphorus, cholesterol, triglyceride, ALK, and LDH decreased from small to large follicles. Phosphorus, albumin, and LDH concentrations in plasma were significantly lower than the levels in all follicle classes. The plasma concentrations of glucose, creatinin, cholesterol, triglyceride, protein, and glubolin were higher than in the small, medium, and large follicles. The concentration of glucose in the small follicles was significantly lower than in the medium and large follicles. Total protein concentration in fluid of small follicles was significantly higher than in the large follicles. The amount of globulin in medium follicles was higher than in the small and large follicles. The plasma concentration of ALK was significantly lower than in the small and medium follicles. ALK concentration difference between large follicles and plasma was not significant.     

Relationship between plasma thyroid hormones and some biochemical parameters in Iranian Sarabi calves

The thyroid gland has some important endocrine hormones that regulate basal metabolism in various tissues of domestic animals. Thyroid hormones have a central role in animals’ development and their tissue functions. In this study, the relationship between the plasma thyroxine (T₄), triiodothyronine (T₃), free thyroxine (fT₄), free triiodothyronine (fT₃), triglyceride, cholesterol, glucose, total protein, and albumin concentrations as well as albumin/globulin ratio in different ages of Iranian Sarabi calves was investigated. Blood samples were collected from the jugular vein of 47 clinically healthy calves free from internal and external parasites (grouped according to their age—1–14 days, 1–2, and 3–6 months) in early of winter. The level of thyroid hormones was determined by chemiluminescence, and other parameters were measured by spectrophotometry using commercial kits. Our data from this study indicates that there was no significant difference and correlation in all the studied parameters between age groups and sexes. But we found a significant correlation between plasma T₄ and total protein (P < 0.05, r = 0.600), T₄ and albumin (P < 0.05, r = 0.575), T₃ and fT₃ (P < 0.05, r = 0.610), T₃ and total protein (P < 0.01, r = 0.725), T₃ and glucose (P < 0.01, r = 0.685), and fT₄ and fT₃ (P < 0.05, r = 0.609) concentrations as well as between total protein and albumin/globulin ratio (P < 0.01, r = −0.783).     

Evaluation of the resistance of indigenous Iranian cattle to Theileria annulata compared with Holstein cattle by measurement of acute phase proteins

This study was conducted to evaluate the resistance of indigenous cattle against Theileria annulata in comparison with that of Holsteins, through assessment of changes in acute phase proteins. Blood samples were collected from 24 indigenous and 26 Holstein dairy cattle, 2–3 years old, which had become naturally infected with T. annulata. Twenty-five healthy cattle, ten indigenous and 15 Holsteins were selected as a control group. The Theileria-infected group were divided into four subgroups according to their parasitemia rates (<1%, 1–3%, 3–5% and >5%). Measurement of red blood cells (RBCs), packed cell volume (PCV), haemoglobin (Hb), haptoglobin (Hp), serum amyloid A (SAA), ceruloplasmin and fibrinogen were done for all animals using validated methods. Results showed significant differences in RBCs, PCV, Hb and concentrations of Hp, SAA, ceruloplasmin and fibrinogen between healthy cattle and those infected with T. annulata with different parasitemia rates in both breeds (P < 0.05). In both breeds, there was significant negative correlation between parasitemia and RBCs, PCV and Hb (P < 0.05). In contrast, with increasing parasitemia rate, a significant increase in MCV, Hp, SAA, ceruloplasmin and fibrinogen was evident. Iranian indigenous cattle in comparison with Holsteins showed lower parasitemia rate, milder clinical manifestations and significantly lower levels of acute phase proteins including Hp, SAA, ceruloplasmin and fibrinogen (P < 0.05).     

Neuromuscular adaptation during prolonged strength training, detraining and re-strength-training in middle-aged and elderly people

Effects of a 24-week strength training performed twice weekly (24 ST) (combined with explosive exercises) followed by either a 3-week detraining (3 DT) and a 21-week re-strength-training (21 RST) (experiment A) or by a 24-week detraining (24 DT) (experiment B) on neural activation of the agonist and antagonist leg extensors, muscle cross-sectional area (CSA) of the quadriceps femoris, maximal isometric and one repetition maximum (1-RM) strength and jumping (J) and walking (W) performances were examined. A group of middle-aged (M, 37–44 years, n=12) and elderly (E, 62–77, n=10) and another group of M (35–45, n=7) and E (63–78, n=7) served as subjects. In experiment A, the 1-RM increased substantially during 24 ST in M (27%, P < 0.001) and E (29%, P < 0.001) and in experiment B in M (29%, P < 0.001) and E (23%, P < 0.01). During 21 RST the 1-RM was increased by 5% at week 48 (P < 0.01) in M and 3% at week 41 in E (n.s., but P < 0.05 at week 34). In experiment A the integrated electromyogram (IEMG) of the vastus muscles in the 1-RM increased during 24 ST in both M (P < 0.05) and E (P < 0.001) and during 21 RST in M for the right (P < 0.05) and in E for both legs (P < 0.05). The biceps femoris co-activation during the 1-RM leg extension decreased during the first 8-week training in M (from 29 ± 5% to 25 ± 3%, n.s.) and especially in E (from 41 ± 11% to 32 ± 9%, P < 0.05). The CSA increased by 7% in M (P < 0.05) and by 7% in E (P < 0.001), and by 7% (n.s.) in M and by 3% in E (n.s.) during 24 ST periods. Increases of 18% (P < 0.001) and 12% (P < 0.05) in M and 22% (P < 0.001) and 26% (P < 0.05) in E occurred in J. W speed increased (P < 0.05) in both age groups. The only decrease during 3 DT was in maximal isometric force in M by 6% (P < 0.05) and by 4% (n.s.) in E. During 24 DT the CSA decreased in both age groups (P < 0.01), the 1-RM decreased by 6% (P < 0.05) in M and by 4% (P < 0.05) in E and isometric force by 12% (P < 0.001) in M and by 9% (P < 0.05) in E, respectively, while J and W remained unaltered. The strength gains were accompanied by increased maximal voluntary neural activation of the agonists in both age groups with reduced antagonist co-activation in the elderly during the initial training phases. Neural adaptation seemed to play a greater role than muscle hypertrophy. Short-term detraining led to only minor changes, while prolonged detraining resulted in muscle atrophy and decreased voluntary strength, but explosive jumping and walking actions in both age groups appeared to remain elevated for quite a long time by compensatory types of physical activities when performed on a regular basis. Accepted: 2 May 2000     

Effects of rearing temperature on hematological and biochemical parameters of great sturgeon (Huso huso Linnaeus, 1758) juvenile

The effect of environmental temperature changes on hematological and biochemical parameters of Huso huso juveniles was studied. Six-month-old juveniles with mean body weight of 69.2 ± 4.1 g were subjected to different temperatures (9–14°C, 15–20°C, and 21–26°C, respectively). The hematological parameters, ion Ca2+, glucose, and the cortisol concentrations were assessed after a period of 21 days rearing at these temperatures. The results show that hematocrit, Ca²⁺, and eosinophil were affected by different temperatures. Increasing temperature led to a significant increase (P < 0.05) in the hematocrit, Ca²⁺, and eosinophil, but white blood cell count, lymphocyte, cortisol, and glucose concentrations were decreased slightly (P > 0.05). The rest of the parameters showed no significant effect with increase in environmental temperature (P > 0.05). These data show significant effect of temperature on the blood parameters of great sturgeon.     

Changes in plasma concentrations of interleukin-6 and interleukin-1 receptor antagonists in response to adrenaline infusion in humans

To investigate the possible role of adrenaline in the response of interleukin (IL)-6 and IL-1 receptor antagonists (ra) to extreme physiological conditions such as trauma and exercise, we examined the concentrations in the plasma of these cytokines during an adrenaline infusion. Given the fact that HIV infected patients have elevated levels of IL-6 in plasma, 12 HIV seropositive subjects and 6 HIV seronegative control subjects received a 1-h adrenaline infusion. Baseline concentrations of IL-6 and IL-1ra were higher in the HIV patients compared with the controls (P < 0.05 and P < 0.01, respectively), being most pronounced in the untreated subgroup of HIV infected patients (n=6). The plasma concentration of adrenaline had increased 24-fold after 15 min of adrenaline infusion. The plasma concentration of IL-6 had increased by two- to threefold after 45 min of adrenaline infusion (P < 0.01) and was still elevated 1 h after the infusion had ended (P < 0.001 and P < 0.05 in controls and HIV infected patients, respectively). The plasma concentration of IL-1ra had increased two- to threefold 1 h after ceasing the adrenaline infusion (P < 0.05 and P < 0.01 in controls and HIV infected patients, respectively). The relative increase in the cytokine levels was similar in controls and HIV infected patients. Thus, HIV infection did not influence the effect of adrenaline on IL-6 and IL-1ra. The present study supports the existence of a relationship between the plasma concentration of adrenaline and IL-6. It is possible that an increased adrenaline concentration in plasma induces a continued de novo synthesis of IL-6, thereby increasing plasma IL-6 in a time–dose dependent manner. Accepted: 16 April 2000     

Effect of xylazine–ketamine–diazepam anesthesia on certain clinical and arterial blood gas parameters in sheep and goats

This study was conducted to evaluate the effect of xylazine–ketamine–diazepam anesthesia on heart rate, respiration rate, rectal temperature, rumen motility, peripheral blood pH, PaO2, and PaCO2 in adult female nonpregnant Awassi sheep and adult female nonpregnant Damascus goats. Anesthesia was induced using 0.1 mg/kg, 5 mg/kg, and 0.25 mg/kg xylazine, ketamine, and diazepam respectively as a single intravenous injection. The heart rate, respiration rate, rectal temperature, rumen motility, peripheral arterial blood pH, PaO2, and PaCO2 were evaluated 15 min before and at 15, 30, and 60 min during anesthesia. In sheep, the heart rate, rumen motility, and PaO2 were decreased significantly (P < 0.05) at 15, 30, and 60 min following anesthesia. The respiration rate and rectal temperature and blood pH were decreased significantly (P < 0.05) at 30 and 60 min. The peripheral PaCO2 was increased significantly (P < 0.05) at 15 and 30 min. In goats, the heart rate and rumen motility were decreased significantly (P < 0.05) at 15, 30, and 60 min while the respiration rate was decreased only significantly (P < 0.05) at 60 min. Rectal temperature was decreased significantly (P < 0.05) at 30 and 60 min. The blood pH was decreased significantly (P < 0.05) at 15 and 30 min. PaO2 was only significantly (P < 0.05) decreased at 15 min while PaCO2 was increased significantly (P < 0.05) at 15 and 30 min.     

Evaluation of erythrocyte antioxidant mechanisms: antioxidant enzymes, lipid peroxidation, and serum trace elements associated with progressive anemia in ovine malignant theileriosis

Ovine malignant theileriosis is a fatal disease that is characterized by severe progressive anemia. In order to elucidate the underlying mechanisms involved in anemia, this study was designed to assess the antioxidant status and erythrocyte oxidative injuries in Iranian fat-tailed sheep that suffered from malignant theileriosis. The infected animals (infected group), composed of 50 Iranian sheep about 1–2 years old, naturally infected with Theileria sp., were divided into three subgroups according to parasitemia rates (<1%, 1–3%, 3–5%), and ten non-infected animals were also selected as the control group. Blood samples were taken and hematological parameters, the activities of antioxidant enzymes including superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase, erythrocyte osmotic fragility, and serum concentrations of some trace elements (copper, iron, zinc, manganese, and selenium), were measured. As an index of lipid peroxidation, the level of malondialdehyde (MDA) was also determined. According to the results, a significant decrease in red blood cell (RBC) count, packed cell volume, the activities of SOD, GPX, and catalase (P < 0.001), and also serum concentrations of Cu, Zn, Mn, and Se (P < 0.05) were evident in the infected sheep. In contrast, significantly increased levels of MDA and erythrocyte osmotic fragility (P < 0.001) as well as serum concentration of iron (P < 0.05) were recorded in the infected animals. The significant decrease in antioxidant enzyme activities and substantial elevated levels of lipid peroxidation and erythrocyte osmotic fragility associated with the increase in parasitemia indicate increased exposure of RBCs to oxidative damage. Also, it appears that disturbed antioxidant defense mechanisms can promote the development of anemia in ovine theileriosis.     

Relationship between the level of plasma insulin and lipid profile in Iranian fat-tailed sheep

Insulin is an important hormone in regulating lipid metabolism in a variety of animal tissues; it can both decrease lipolysis and cause an increase in triglyceride synthesis of adipose tissue in ruminants. In this study, variations in the plasma concentration of insulin and its correlation with the plasma cholesterol, triglyceride, high-density lipoprotein (HDL cholesterol), low-density lipoprotein (LDL cholesterol), and very-low-density lipoprotein (VLDL) concentrations were investigated. Blood samples were collected from the jugular vein of 96 clinically healthy, non-pregnant ewes (grouped according to their age 1–3, 3–6, 6–12, 12–24, 24–48, and >48 months) in the autumn months. The level of plasma insulin was determined by chemiluminescence and other parameters were measured by spectrophotometry using commercial kits. According to our data from Iranian fat-tailed sheep, increasing age results in significant decrease in the plasma concentration of insulin (p < 0.05, r = −0.278), cholesterol (p < 0.05, r = −0.249), and HDL (p < 0.01, r = −0.299), there was also a significant correlation between plasma insulin and LDL concentration (p < 0.05, r = 0.268). In addition, we found significant differences between age groups for cholesterol and HDL concentrations (p < 0.05).     

Cardiac, arterial and venous adaptation to weightlessness during 6-month MIR spaceflights with and without thigh cuffs (bracelets)

The objectives of this investigation were to study the effects of thigh cuffs (bracelets) on cardiovascular adaptation and deconditioning in 0 g. The cardiovascular parameters of six cosmonauts were measured by echocardiography, Doppler, and plethysmography, during three 6-month MIR spaceflights. Measurements were made at rest during preflight (−30 days), inflight (1, 3–4, and 5–5.5 months) without cuffs (morning) and after 5 h with cuffs, and during postflight (+3 and +7 days). Lower-body negative pressure (LBNP) measurements were performed 1 day after each resting session. Inflight values of left ventricle end-diastolic volume and stroke volume measured without the thigh cuffs (−8 to −24% and −10 to −16%, respectively, both P < 0.05) were lower than corresponding preflight values. The jugular and femoral vein cross-sectional areas (A _jv and A _fv, respectively) were enlarged (A _jv: by 23–30%, P < 0.001; A _fv: by 33–70% P < 0.01). The renal and femoral vascular resistances (R _ra and R _fa, respectively) decreased (R _ra: by −15 to −16%, P < 0.01; R _fa: by −5 to −11%, P < 0.01). Inflight, the thigh cuffs reduced the A _jv (by −12 to −20%, P < 0.02), but enlarged the A _fv (A _fv: by 9–20%, P < 0.02) and increased the vascular resistance (R _ra: by 8–13%, P < 0.05; R _fa: by 10–16%, P < 0.01) compared to corresponding inflight, without-cuffs values. During LBNP (−45 mmHg, where 1 mmHg=133.3 N/m²), R _fa and the ratio between cerebral and femoral blood flow (Q˙ _ca/Q˙ _fa) increased less inflight and postflight (+25% for R _fa and +30% for Q˙ _ca/Q˙ _fa) than during preflight (60% for R _fa and 75% for Q˙ _ca/Q˙ _fa, P < 0.01). This reduced vasoconstrictive response and less efficient flow redistribution toward the brain was associated with orthostatic intolerance during postflight stand tests in all of the cosmonauts. The calf circumference increased less inflight and postflight (6% P < 0.05) than preflight (9% P < 0.05). The vascular response to LBNP remained similarly altered throughout the flight. The thigh cuffs compensated partially for the cardiovascular changes induced by exposure to 0 g, but did not interfere with 0 g deconditioning. Accepted: 5 November 1999     

Cutaneous vasomotor adjustments during arm-cranking in individuals with paraplegia

Skin blood flow (SKBF) was evaluated during arm-cranking exercise in able-bodied control subjects (AB; n=6) and in individuals with low- (LP; T10–T12 lesions; n=6) and high-level paraplegia (HP; T5–T9 lesions; n=6), using laser Doppler flowmetry (LDF). During moderate exercise SKBF decreased to [mean (SD)] 82 (15)% of the pre-exercise resting level in AB, whereas it increased to 158 (52)% in LP and to 112 (51)% in HP (the LP:AB difference, P < 0.05). During intense exercise SKBF increased to 366 (180)% of the resting level in AB, whereas it increased only moderately [147 (68)%] in both paraplegic groups (the paraplegic:AB difference, P < 0.05). The paraplegics developed a higher esophageal and leg skin temperature, which was attributed to the lack of active vasodilation and evaporative cooling over the legs. The results indicate that individuals with paraplegia suffer from impaired cutaneous vasoconstriction at the onset of arm exercise, and possess only a limited vasodilatory capability in the paralyzed regions. During intense exercise, thermoregulation depends critically on active cutaneous vasodilation and skin cooling. Accepted: 25 August 2000     

Prevalence and haemato-biochemical parameters of trypanosome-infected pigs at Nsukka, Nigeria

The haematological and biochemical parameters of pigs slaughtered at the Nsukka Abattoir between March and May, 2009 with trypanosome infection were evaluated. A total of 300 pigs were screened for trypanosome infection using parasitological diagnostic methods. Twelve (4%) of the pigs were found to be infected. All infections were due to Trypanosoma brucei. The infected blood samples, and an equivalent non-infected (control) blood were subjected to haematological and biochemical analysis. The packed cell volume (PCV) of the infected and non-infected pigs ranged between 14–50% (mean 27.8 ± 2.8) and 23–42 (36.25 ± 0.97) and differed significantly (P < 0.05). Infection had no significant (P > 0.05) effect on the other blood parameters. Total protein (TP), albumin (ALB) and creatine showed no significant difference (P > 0.05) whereas aspertate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), urea and total bilirubin differed significantly (P < 0.05) between the infected and non-infected pigs. All these parameters increased in the infected animals with the exception of ALP which decreased. This study confirms the preponderance of T. brucei in the pig population of Nsukka area, Nigeria. It further reveals that significant haematocrit and serum biochemical changes occurred in the infected pigs. These findings are thought to have potential public health and some diagnostic significance.     

Serum thyroid hormones and trace element concentrations in crossbred holstein cattle naturally infected with Theileria annulata

This research was carried out to study thyroid function in view of serum trace element and possible serum cortisol concentration changes in crossbred Holstein cattle naturally infected with Theileria annulata. Twenty cattle of different age and sex which had been naturally infected with T. annulata were examined. A control group were selected among the clinically healthy crossbred Holstein cattle with the same age, sex, and production stage similar to the naturally infected group. Serum T3, T4 concentrations were significantly lower in cattle suffering from theileriosis than in the healthy controls (p < 0.05). The cattle suffering from theileriosis had significantly lower concentrations of zinc and selenium in their sera as compared with the healthy control subjects (p < 0.05). Lower packed cell volume (PCV) theileriosis-affected cattle had a lower serum selenium concentration than higher PCV-affected group (p < 0.05). Significant differences were also found in PCV, total protein, albumin and total bilirubin concentrations and alkaline phosphatase and gama-gluthamyl transferase activities between theileriosis-affected and healthy cattle (p < 0.05). Total protein and albumin concentrations were statistically different in age (less and more than two years) and PCV (lower and higher) groups of theileriosis-affected cattle (p < 0.05). No significant changes were found in free T3, free T4, cortisol, copper, cobalt, and manganese levels of theileriosis-affected cattle.     

Nephropathia epidemica and leptospirosis in Champagne-Ardenne,France: comparison of clinical,biological and epidemiological profiles

In the present retrospective study, we described a series of 45 non-icteric leptospirosis and 44 nephropathia epidemica (NE) patients diagnosed in the northeast of France from 1995 to 2005 and compared their clinical picture and laboratory parameters, as well as some epidemiological data. Loin pain (P < 0.001), abdominal pains (P = 0.007), rise of blood pressure (P < 0.001) and pharyngitis (P = 0.01) were more frequently found in NE patients. Aspartate aminotransferase (ASAT) (P = 0,006), creatine phosphokinase (CPK) (P < 0.0001) and C-reactive protein (CRP) (P < 0.0001) were higher in leptospirosis, whereas creatinine (P = 0.009) was higher in NE. Leptospirosis mainly concerns occupational hazards, e.g. farmers, and leisure activities like swimming, and NE concerns professional foresters or leisure activities in the forest and the cleaning of attics. During hospitalisation, patients receiving antibiotics were more frequent among leptospirosis than among NE patients (80% versus 59%, P = 0.06). Among the various common clinical signs, only acute myopia appeared to be a pathognomonic but inconsistently observed clinical sign, which was only observed in 47% of NE cases.     

Alterations in the expression and activity of creatine kinase-M and mitochondrial creatine kinase subunits in skeletal muscle following prolonged intense exercise in rats

Creatine kinase (CK) isoenzymes are important structural and energy metabolism components in skeletal muscle. In this study, CK isoenzyme alterations were examined in male rats, with an 8% body mass weight attached to their tail. The rats were either forced to swim for 5 h (5S, n = 51), or were pre-trained for 8 days and then forced to swim for 5 h (T5S, n = 48). Rats were sacrificed either immediately (0 h PS), 3 h (3 h PS), or 48 h post-swimming (48 h PS). Serum CK was increased significantly (P < 0.01) 6.2- and 2.0-fold at 0 h PS following the 5S and T5S protocols, respectively. However, training (T5S protocol) significantly (P < 0.01) decreased CK release. Soleus and white gastrocnemius (WG) CK activity was significantly decreased following the 5S protocol (P < 0.05), but not following the T5S protocol. The CK-M activity of the soleus muscle was significantly (P < 0.05) decreased at 0 h PS following both the 5S and T5S protocols, and returned to control values at 3 h PS. The CK-M activity of the WG was significantly (P < 0.05) decreased at 0 h PS following the 5S protocol. Sarcomeric mitochondrial CK (sCK-Mit) was decreased significantly (P < 0.01) at 0 h PS (20%), 3 h PS (14%), 24 h PS (22%), and 48 h PS (15%) following the 5S protocol. However, sCK-Mit was decreased significantly (P < 0.01) only at 0 h PS (7%) following the T5S. The results of this study demonstrate that prolonged intense exercise causes a loss of skeletal muscle CK-M and sCK-Mit activity and that training prior to the prolonged intense exercise attenuates the exercise-induced CK-M and sCK-Mit loss in both red and white skeletal muscles. Accepted: 18 July 1999     

Dose dependency of prednisolone tertiary-butylacetate (PTBA) treatment on the establishment and site predilection of Echinococcus multilocularis in an alternative definitive host model using Mongolian gerbil (Meriones unguiculatus)

Mongolian gerbils (Meriones unguiculatus) were orally inoculated with 10,000 protoscoleces of Echinococcus multilocularis per head after being divided into five groups (A–E). Each group was dosed with prednisolone tertiary-butylacetate (PTBA) as follows: A, 0 mg; B, 0.5 mg; C, 2 mg; D, 5 mg; and E, 10 mg/head. All animals were injected subcutaneously with control solvent or PTBA every other day from 6 days pre- to 6 days post-infection. Autopsy was performed at 7 days post-infection. Doses of PTBA and the number of worms recovered showed a positive correlation (r=0.929, P < 0.0001). In groups A, B and C, the predilection site of the worms in the small intestine could not be determined, while in group D the worms were found more in the anterior part. In group E, the predilection site was the anterior part, followed by the middle and the posterior parts of the small intestine (Fisher's test: P < 0.01). The number of worms recovered from the anterior and the middle part of the small intestine also correlated positively with PTBA dose (anterior part: r=0.930, P < 0.0001, middle part: r=0.917, P < 0.0001). All groups of the PTBA-treated animals showed significant loss of weight compared to the non-treated animals (P < 0.01). Received: 26 September 1999 / Accepted: 24 November 1999     

Short-term exercise training improves diaphragm antioxidant capacity and endurance

These experiments tested the hypothesis that short-term endurance exercise training would rapidly improve (within 5 days) the diaphragm oxidative/antioxidant capacity and protect the diaphragm against contraction-induced oxidative stress. To test this postulate, male Sprague-Dawley rats (6 weeks old) ran on a motorized treadmill for 5 consecutive days (40–60 min · day⁻¹) at approximately 65% maximal oxygen uptake. Costal diaphragm strips were excised from both sedentary control (CON, n=14) and trained (TR, n=13) animals 24 h after the last exercise session, for measurement of in vitro contraction properties and selected biochemical parameters of oxidative/antioxidant capacity. Training did not alter diaphragm force-frequency characteristics over a full range of submaximal and maximal stimulation frequencies (P > 0.05). In contrast, training improved diaphragm resistance to fatigue as contraction forces were better-maintained by the diaphragms of the TR animals during a submaximal 60-min fatigue protocol (P < 0.05). Following the fatigue protocol, diaphragm strips from the TR animals contained 30% lower concentrations of lipid hydroperoxides compared to CON (P < 0.05). Biochemical analysis revealed that exercise training increased diaphragm oxidative and antioxidant capacity (citrate synthase activity +18%, catalase activity +24%, total superoxide dismutase activity +20%, glutathione concentration +10%) (P < 0.05). These data indicate that short-term exercise training can rapidly elevate oxidative capacity as well as enzymatic and non-enzymatic antioxidant defenses in the diaphragm. Furthermore, this up-regulation in antioxidant defenses would be accompanied by a reduction in contraction-induced lipid peroxidation and an increased fatigue resistance. Accepted: 6 August 1999     

Comparative study on determination of plasma thyroid hormones by chemiluminescence and electrochemiluminescence immunoassay methods in sheep

The aim of this study was to compare plasma thyroid hormone concentrations by both chemiluminescence (CLIA) and electrochemiluminescence immunoassay (ECLIA) methods in sheep. Blood samples were taken from the jugular vein of 25 clinically healthy, non-pregnant adult ewes. The plasma was analyzed to determine thyroxine (T₄), tri-iodothyronine (T₃), free thyroxine (fT₄) and free tri-iodothyronine (fT₃) concentrations. The data from this study indicates, there were significant differences in the T₄ (P < 0.0001), T₃(P < 0.01) and fT₃(P < 0.01) concentrations between the two methods, and the levels of these hormones were higher when using the ECLIA method. In determining thyroid hormones using the CLIA and ECLIA methods, significant positive correlations were found between T₄ and fT₄ (P < 0.001, r = 0.703; P < 0.0001, r = 0.806) also between T₃ and fT₃ (P < 0.0001, r = 0.922; P < 0.0001, r = 0.923) concentrations, respectively. The linear regression analysis of these hormones showed that the CLIA and ECLIA results were significantly correlated (T₄ (P < 0.01, r = 0.583), T₃ (P < 0.0001, r = 0.898), fT4 (P < 0.0001, r = 0.796) and fT₃ (P < 0.0001, r = 0.898).     

Lipid and lipoprotein profiles, cardiovascular fitness, body composition, and diet during and after resistance, aerobic and combination training in young women

The purpose of this study was to evaluate the effects of various modes of training on the time-course of changes in lipoprotein-lipid profiles in the blood, cardiovascular fitness, and body composition after 16 weeks of training and 6 weeks of detraining in young women. A group of 48 sedentary but healthy women [mean age 20.4 (SD 1) years] were matched and randomly placed into a control group (CG, n=12), an aerobic training group (ATG, n=12), a resistance training group (RTG, n=12), or a cross-training group that combined both aerobic and resistance training (XTG, n=12). The ATG, RTG and XTG trained for 16 weeks and were monitored for changes in blood concentrations of lipoprotein-lipids, cardiovascular fitness, body composition, and dietary composition throughout a 16 week period of training and 6 weeks of detraining. The ATG significantly reduced blood concentrations of triglycerides (TRI) (P < 0.05) and significantly increased blood concentrations of high-density lipoprotein-cholesterol (HDL-C) after 16 weeks of training. The correlation between percentage fat and HDL-C was 0.63 (P < 0.05), which explained 40% of the variation in HDL-C, while the correlation between maximal oxygen uptake (V˙O_2max) and HDL-C was 0.48 (P < 0.05), which explained 23% of the variation in HDL-C. The ATG increased V˙O_2max by 25% (P < 0.001) and decreased percentage body fat by 13% (P < 0.05) after 16 weeks. Each of the alterations in the ATG had disappeared after the 6 week detraining period. The concentration of total cholesterol (TC), TRI, HDL-C and low density lipoprotein-cholesterol in the blood did not change during the study in RTG, XTG and CG. The RTG increased upper and lower body strength by 29% (P < 0.001) and 38%, respectively. The 6 week detraining strength values obtained in RTG were significantly greater than those obtained at baseline. The XTG increased upper and lower body strength by 19% (P < 0.01) and 25% (P < 0.001), respectively. The 6 week detraining strength values obtained in XTG were significantly greater than those obtained at baseline. The RTG, XTG and CG did not demonstrate any significant changes in either V˙O_2max, or body composition during the training and detraining periods. The results of this study suggest that aerobic-type exercise improves lipoprotein-lipid profiles, cardiorespiratory fitness and body composition in healthy, young women, while resistance training significantly improved upper and lower body strength only. Accepted: 9 April 2000     

Seroprevalence of and risk factors for Toxoplasma gondii antibodies among asymptomatic blood donors in Egypt

A cross-sectional study was conducted to evaluate the seroprevalence of and risk factors for Toxoplasma gondii antibodies in 260 blood donors seen at blood banks in Mansoura University Hospital, Egypt. Blood donors were interviewed about sociodemographic characteristics and risk factors for T. gondii infection. A blood sample was taken to document their T. gondii antibody status using enzyme-linked immunosorbent assay. Overall, 155 (59.6%) of 260 blood donors were positive for anti-T. gondii IgG antibodies. Multivariate logistic regression analysis showed a significant association between T. gondii seropositivity and eating meat by-products (luncheon/shawerma) (adjusted odds ratio [OR] 80.82 [95% CI 18.62–350.81], P < 0.0001) or being non-educated (adjusted OR 32.25 [95% CI 7.46–139.44], P < 0.0001). These findings highlight that T. gondii is prevalent among blood donors in Egypt.