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1.
Cryopreservation of equine embryos > 300 μm in diameter results in low survival rates using protocols that work well for smaller equine embryos. These experiments tested the potential benefit of incorporating a dehydration step prior to standard cryopreservation procedures. Forty-six, day 7–8, grade 1, equine embryos 300–1350 μm in diameter were subjected to one of the following treatments: (A) 2 min in 0.6 M galactose, 10 min in 1.5 M glycerol, slow freeze (n = 21); (B) 10 min in 1.5 M glycerol, slow freeze (n = 15); (C) 2 min in 0.6 M galactose, 10 min in 1.5 M glycerol, followed by exposure to thaw solutions, then culture medium (n = 5); (D) transferred directly to culture medium (n = 5). Frozen embryos were thawed and subjected to a three-step cryoprotectant removal. Five embryos from each treatment were evaluated morphologically after 24 and 48 h culture (1 = excellent, 5 = degenerate/dead). All treatments had at least 4/5 embryos with a quality score  3 at these time points except treatment B (2/5 at 24 h, 1/5 at 48 h). Subsequent embryos from treatment A (n = 16) or B (n = 10) were matched in sets of two for size and treatment, thawed, and immediately transferred in pairs to 13 recipients. Only two recipient mares were pregnant; one received two 400 μm embryos from treatment A, and the other one 400 and one 415 μm embryo from treatment B. There was no advantage of incorporating a 2 min dehydration step into the cryopreservation protocol for large equine embryos.  相似文献   

2.
In this study, two total mixed rations (TMR, based on dry ingredients) consisting (per kg dry matter (DM)) of 300 or 400 g finely chopped hay mixture of grass and alfalfa (H30 versus H40) were compared concerning their effects on dry matter intake (DMI), ruminal fermentation patterns and chewing activity of early-weaned (8 weeks milk-fed) calves. Ten ruminally cannulated male German Holstein calves were randomly assigned to two dietary treatments (n = 5) and observed from an age of 8–15 weeks. One group received the H30 (11.3 MJ metabolizable energy (ME)/kg DM) and the other the H40 (10.7 MJ ME/kg DM) TMR. All calves received grass hay (9.0 MJ ME/kg DM) separately. Water, TMR and hay were offered ad libitum twice daily (08:00 and 16:00 h). Rumen fluid was collected via cannula at an age of 9, 11, 13 and 15 weeks, twice weekly just prior to as well as 1, 3, 5 and 7 h after morning feeding. Chewing activity was recorded by a special head collar. As the calves aged DMI increased rapidly congruent with the recommended range for weaned calves. Because of the differing energy supply, calves receiving the H30 TMR were heavier than calves receiving the H40 TMR (139 kg versus 123 kg, P=0.007). During the trial ruminal pH of all calves were within the target range (6.2 ± 0.5), indicating physiological ruminal fermentation patterns. Daily mean ruminal pH was uninfluenced by treatment, however at an age of 13 and 15 weeks H30 showed a higher short chain fatty acid (SCFA) level than H40 (P=0.098; P=0.036). At an age of 15 weeks H30 showed a critical decrease in ruminal pH (3 h after feeding: 5.7) corresponding to a higher ruminal SCFA concentration (148.2 mmol/L, P=0.007). Chewing activity was well developed at an early age due to an increasing DMI after weaning. At an age of 15 weeks chewing activity (per day: 613–743 min total chewing; 358–418 min rumination) was similar to that of adult cows. In summary, feeding a dry TMR consisting per kg DM of 300–400 g hay to early-weaned calves can be recommended for a successful calf rearing up to an age of 15 weeks.  相似文献   

3.
Use of a blindfold or hood during handling and restraint has been suggested for many wild and captive animals. Two experiments were conducted to determine the effects of blindfolds on beef cattle during restraint. In Experiment 1, 60 beef heifers, naı̈ve to the restraint facility, were randomly assigned to either visual restriction (blindfold) or no visual restriction (control) and tested daily during a 4-day trial to determine the effects during restraint. Heart rate (HR) was measured via telemetry, during a baseline period prior to treatment and continuously recorded during a 1-min period of restraint, which included some manipulation of the animal. Manipulation was initiated 15 s into the restraint period. Two persons simultaneously approached the animal one on either side, grasped the ears, and touched the neck, sides and rump to simulate normal management tasks. Electronic strain gauges attached to the head gate quantified the animal’s struggle during this procedure. These were used to determine the average and maximum exertion forces upon the head gate during restraint. The association between treatment, sample time (day 0–4), animal weight and the various outcome measures were analyzed using a generalized estimating equation method. Mean HR of heifers did not differ at the end of the treatment (95.04±4.66 bpm ) (P=0.64), but the HR tended to decrease more for blindfolded heifers compared to controls during restraint (average decrease 16.3±3.2 bpm and 14±2.9 bpm, respectively) (P=0.10). The average exertion forces applied by blindfolded heifers against the head gate were 23% lower (P<0.05) during the 1-min period and maximum forces were 28% lower (P<0.01). Heart rate and exertion forces declined over the 4 days for both treatment groups (P<0.001). In Experiment 2, 93 commercial beef calves (average age 92.9±2.0 days) were randomly assigned to either visual restriction (blindfold) (n=46) or no visual restriction (control) (n=47) treatments. Behavioral responses to treatment were quantified by measuring the amount of movement and recording the number of vocalizations while the calves were restrained for 1 min on a calf tilt table. Movement was recorded by an electronic device attached to a weighing platform that held the tilt table. After 30 s of restraint, one experimenter touched the animal’s ear while the other touched the neck, to simulate ear tagging and vaccination. Blindfolded calves moved 44% less than the control group (P<0.01). However, the number of vocalizations that occurred during the 1-min test period did not differ (P>0.05) between treatments. Overall, blindfolding cattle reduced the amount of struggle and tended to lower heart rate. Therefore, blindfolding may be advantageous during the routine invasive procedures commonly performed on cattle.  相似文献   

4.
The present study examined the effect of delayed treatment with tropic hormones and progesterone (P4) on embryonic mortality in buffaloes. Buffaloes with a conceptus on Day 25 after AI were assigned to the following treatments: Control (n = 41), i.m. physiological saline; GnRH agonist (n = 36), i.m. 12 μg buserelin acetate; hCG (n = 33), i.m. 1500 IU hCG; P4 (n = 38), i.m. 341 mg P4 every 4 days on three occasions. Control buffaloes had an embryonic mortality of 41.4% (17/41) between Days 25 and 45, and this was reduced (P < 0.01) by treatment with GnRH agonist (11.1%, 4/36), hCG (9.0%, 3/33) and P4 (13.1%, 5/38). On Day 45, buffaloes treated with hCG and which ovulated had greater (P < 0.05) concentrations of P4 in whey (453 ± 41 pg/ml) than buffaloes in the same treatment that did not ovulate (297 ± 32 pg/ml). A similar but non-significant trend was observed for buffaloes treated with GnRH agonist. It was concluded from the findings that the treatment of buffaloes on Day 25 after AI with tropic hormones or P4 is beneficial to processes associated with embryonic implantation.  相似文献   

5.
Tactile contact is often used to improve the human–foal relationship, in particular during sensitive periods such as weaning. However, the method used to provide the contact (forced or unforced) may affect subsequent reactions to humans. The aim of our study was to compare the effect of forced and unforced handling at weaning on horses’ behaviour towards humans and handling.A total of 23 Anglo-Arabian foals received individual human contact at weaning. Constrained-handled foals (forced human contact; FC, n = 8) were stroked while being restrained (i.e., held by the halter without being led) so that human contact was forced. Unconstrained-handled foals (unforced human contact; UC, n = 7) were stroked without any restraint and could thus avoid contact if they so wanted. Each individual was handled 5 min twice a day for 14 consecutive days. Control foals were not handled (no contact; NC, n = 8). Foals’ reactions towards a human (e.g. proximity and contact seeking), and their manageability (fitting of a halter) were then assessed. The animals from the different treatments were then mixed and tested again 4 months later. Non-parametric Mann–Whitney U-tests were used to compare experimental groups.Only forced human contact reduced fear reactions toward humans (e.g. shorter latency to approach a passive human, P < 0.01; shorter latency to touch the foal, P < 0.05) in the short-term (immediately after the handling sessions) and increased foals’ manageability in a familiar environment (shorter latency to be placed a halter on and less defences displayed, P < 0.05). It had no effect in an unfamiliar environment. These effects did not last longer than 4 months.Forced human contact thus appears to be more efficient in improving human–horse relationships and subsequent handling than unforced human contact. However, the lack of effect on reactivity towards humans in an unfamiliar environment, and the lack of long-term effects suggest that this method needs to be improved to be more effective. Some of our results suggest that horses could perceive human contact (i.e., stroking) as positive, however further studies are needed to confirm this hypothesis.  相似文献   

6.
Cold therapy is used to relieve pain and inflammatory symptoms. Humoral changes may account for the pain alleviation related to the cold exposures. The aim of the present study was to examine the effects of two types of cold therapy, winter swimming in ice-cold water (WS) and whole body cryotherapy (WBC), on the serum levels of the growth hormone, prolactin, thyrotropin and free fractions of thyroid hormones (fT3, fT4). One group of healthy females (n = 6) was exposed to WS (water 0–2 °C) for 20 s and another group (n = 6) to WBC (air −110 °C) for 2 min, three times a week for 12 weeks. Blood samples used for the hormone measurements were taken on weeks 1, 4 and 12 before and 35 min after the cold exposures and on the days of the respective weeks, when the cold exposures were not performed. During the WS treatments, serum thyrotropin increased significantly at 35 min on weeks 1 (p < 0.01) and 4 (p < 0.05), but the responses were within the health-related reference interval. During the WS, the serum prolactin measured at 35 min on week 12 was lower than during the control treatment, and no changes in fT3 or fT4 were observed. During the WBC, no changes in the serum levels of the studied hormones were observed during the 12 weeks. In conclusion, repeated WS and WBC treatments for healthy females do not lead to disorders related to altered secretions of the growth hormone, prolactin, thyrotropin, or thyroid hormones.  相似文献   

7.
In a variety of animal models, uroguanylin causes diuresis, natriuresis and kaliuresis and is found in larger concentrations in the urine compared to controls after oral salt intake or in conditions of excess salt and fluid retention. It has been proposed that uroguanylin functions as an intestinal natriuretic hormone following intake of meals high in salt content. In the present work, we examined if 10 days of salt ingestion resulted in an enhanced response to uroguanylin in the isolated perfused rat kidney. Rats were given normal water, 1% NaCl (HS1%), or 2% NaCl (HS2%) for 10 days, at which time the right kidneys were surgically removed and perfused with a modified Krebs-Henseleit solution for 30 min. After a 30-min control period, the kidneys were perfused with a modified Krebs-Henseleit solution containing 0.06 μM uroguanylin for an additional 90 min. Compared to vehicle-matched time controls, 0.06 μM uroguanylin perfusion of kidneys from rats maintained on HS2% resulted in a significantly increased urine flow (UF; from 0.17 ± 0.01 to 0.23 ± 0.01, after 60 min, n = 6, P < 0.05), fractional Na+ excretion (%ENa+; from 16.6 ± 0.7 to 30 ± 2, after 60 min, n = 6, P < 0.05), fractional K+ excretion (%EK+; from 20.5 ± 0.58 to 37.4 ± 2.1, after 60 min, n = 6, P < 0.05), and fractional Cl excretion increased from 18.16 ± 0.52 to 35.2 ± 2.0 at 60 min, n = 6, P < 0.05. With the exception of a significant increase in the %EK+, no other effect was observed in the kidneys from the rats maintained on HS1%, and no significant effects were seen in those that were maintained on normal water. The effect of a higher dose (0.6 µM) of uroguanylin on urinary flow, sodium or potassium excretion was also significantly increased by 2% NaCl (HS2%) treatment (P < 0.05). We also observed an expressive upregulation of the GC-C and a slight downregulation of the GC-A receptor in high-salt treated rats. These data demonstrate that prolonged salt ingestion primes the kidney to enhanced renal responses to uroguanylin.  相似文献   

8.
Effect of low density lipoprotein on the quality of cryopreserved dog semen   总被引:1,自引:0,他引:1  
Egg yolk is included in extenders for semen cryopreservation due to its protective effect against cold shock, which is attributed to the presence of low density lipoprotein (LDL). This study evaluates how semen quality is affected by using LDL as a replacement for egg yolk in extenders for cooled and frozen dog semen. In Experiment 1, semen was extended in TRIS–glucose at 5 °C, in four treatments: 20% egg yolk (T1); 6% (T2); 8% (T3); and 10% LDL (T4). Sperm motility and membrane integrity after 24, 48, 72 and 96 h and the 50% conservation rate of motile spermatozoa (50 M) were evaluated. The 50 M was less for T1 than for the other treatments (P < 0.01), but T2–T4 did not differ (P > 0.05). In Experiment 2, glycerol at 10% was included in the freezing extender, in treatments similar to those from Experiment 1. Sperm motility and membrane integrity did not differ for T2, T3 and T4 at any period in Experiment 1 and after thawing in Experiment 2 (P > 0.05), but were greater for all LDL treatments than for T1 (P < 0.01), in both experiments. Thus, LDL can replace egg yolk in the composition of the TRIS–glucose extender for cooled or frozen dog semen.  相似文献   

9.
To investigate microvascular hyperpermeability and thrombosis induced by photodynamic therapy or light/dye treatment, we quantified the initiation time for thrombus formation, thrombus growth rate, and the time for the microvessel occlusion in post-capillary venules of rat mesenteries. Under similar light/dye treatments, we also measured the microvessel hydraulic conductivity (Lp) and solute permeability (P) to TRITC-BSA (bovine serum albumin), respectively, in the same type of microvessels as for thrombosis. Under an irradiation power of 0.37 mW/mm2, thrombus was initiated in 3.8 ± 0.4 min, its growth rate was 3.9 ± 0.3% of the vessel mid-plane area/min, and the microvessels were completely occluded in 29.3 ± 2.2 min (SE, n = 8). Under the same irradiation power, Lp and P increased gradually, reaching a plateau in 3–5 min. At the plateau, Lp had increased to 2.2 ± 0.2 times (n = 11), while P had increased to 4.1 ± 0.7 (n = 7) times their baseline values, respectively. Neither Lp nor P increased further after longer time exposure (up to 30 min). Comparison of the measured Lp and P data with predictions from a mathematical model for the inter-endothelial cleft suggests that an almost complete depletion of the glycocalyx layer at the luminal surface of the endothelium might be one of the structural mechanisms by which the light/dye increases microvascular permeability and induces thrombosis.  相似文献   

10.
The objectives of this experiment were to evaluate the effect of early human contact and of the separation method from the dam on the future relationships of calves with humans, and to investigate the relationship between dam responses and calf responses. Thirty-three Salers calves aged 2–4 days old and reared outdoors were split into 3-week treatments balanced according to sex and birth dates. Group 1 (long separation from the dam and human contact: LS + H; n = 11) underwent 8 h of separation from the dam per day and 5 min of individual stroking; group 2 (short separation from the dam and human contact: SS + H; n = 11) underwent 1 h of separation and the same amount of human contact as LS + H calves. Group 3 (short separation from the dam and no human contact: SS − H; n = 11) was a control group undergoing the same duration of separation as SS + H but without stroking. At 3, 15 and 45 weeks of age, the calves were tested in a standard arena test (AT) where they were successively left alone (2 min), left with a stationary human (5 min), and left with a human approaching and touching them (2 min). At 15 and 45 weeks, the calves were also tested with the standard docility test (DT: test of restraint). The dams were also tested with DT 2 months before calving. Data analysis via Mann–Whitney tests and Spearman's correlations showed no significant effect of the duration calves were separated from their dams. Just after treatment at 3-week of age, calves given stroking (LS + H and SS + H) were more motionless and more willing to accept human contact (AT: touching) than control calves (SS − H, P < 0.01). At 45 weeks of age, calves given stroking spent also significantly more time (P < 0.05) motionless with the approaching human compared to non-stroked calves (SS − H), suggesting a persistent effect. However, this effect was not reproduced on the other behavioural criteria recorded (e.g., duration of human contact or docility score). In the different tests and at the different ages, the docility scores of the dams were significantly correlated (up to 0.7, P < 0.01) with behaviour towards humans shown by stroked calves but not non-stroked calves (SS − H). Our results suggest that additional human contact at early age, but not duration of the separation from the dam, could be beneficial for the human–animal relationship, but only for calves born to docile dams.  相似文献   

11.
12.
It has been suggested that ultrasound image attributes are a potential indicator of physiological and functional status of the corpus luteum (CL) in several species, including cattle. The aims of this study were to evaluate CL morphological, functional and echotextural characteristics, and also to investigate the hypothesis that those attributes are correlated and change similarly throughout an estrous cycle. Ovaries of crossbred (Bos taurus taurus × Bos taurus indicus) heifers were evaluated using ultrasonography daily throughout an interestrus interval using a B-mode, real-time ultrasound machine equipped with a 5 MHz linear-array rectal transducer, during a natural estrous cycle (Experiment 1; n = 12) or during a shortened cycle, with luteolysis induction 10 d after estrus (Experiment 2; n = 6). Blood samples were collected for assay of plasma progesterone concentrations. Corpora lutea areas were measured and daily images of each CL were videotaped and digitized for computer-assisted analysis using custom-developed software. In Experiment 1, area of luteal tissue increased until a maximum value 10 d after estrus (P < 0.001), followed by a plateau phase, and then a decline beginning 14 d after estrus. Luteal tissue area was highly correlated to plasma progesterone concentrations (r = 0.86; P < 0.001). When luteolysis was induced in Experiment 2, loss of CL function (decrease in plasma progesterone concentrations to metestrous values) preceded tissue regression by 48 h (24 h compared with 72 h; P < 0.001). The mean pixel value of ultrasound images did not change in Experiment 1 (P > 0.70), but a day effect on this attribute was observed in Experiment 2 (P = 0.052). In contrast, mean pixel value was correlated to plasma progesterone concentrations in Experiment 1 (r = −0.63; P < 0.05), but not in Experiment 2 (r = −0.28; P > 0.10). In regard to CL heterogeneity, defined as the standard deviation of the mean pixel value of the luteal tissue, a time effect was observed following both natural (Experiment 1; P < 0.009) and luteolysis-induced (Experiment 2; P < 0.05) estrous cycles (P < 0.05). Moreover, this variable was correlated with plasma progesterone concentrations (r = −0.71 and −0.58 in Experiments 1 and 2, respectively; P < 0.01), indicating that CL images were more heterogeneous during metestrus and after luteolysis (functional regression). In summary, morphological and echotextural attributes were correlated with CL function and underwent similar changes during the estrous cycle. Luteal tissue heterogeneity, assessed by ultrasonography, is considered a potential indicator of CL functional status, because it is correlated to circulating progesterone concentrations.  相似文献   

13.
Interleukin-6 and procalcitonin in children with sepsis and septic shock   总被引:3,自引:0,他引:3  
Objectives. To examine the behavior of interleukin-6 (IL-6) and procalcitonin (PCT) and verify whether they can be used to differentiate children with septic conditions. Methods. Septic children aged between 28 days and 14 years, prospectively enrolled from 01/2004 to 12/2005, were divided into sepsis (SG; n = 47) and septic shock (SSG; n = 43) groups. IL-6 and PCT were measured at admission (T0) and 12 h later (T12h). PCT results were classed as: 0.5 ng/mL = sepsis unlikely; 0.5 to <2 = sepsis possible; 2 to <10 = systemic inflammation; 10 = septic shock. Results. Ninety children were included. At T0, there was a higher frequency of SSG with higher PCT compared with SG [SSG: 30 (69.7%) > SG: 14 (29.8%); p < 0.05]. Similar results were observed at T12h. PRISM was significantly higher for SSG patients with higher PCT than SG patients. At T0, IL-6 levels were higher in SSG [SSG: 213.10 (10.85–396.70) > SG: 63.21 (0.86–409.82); p = 0.001], but not statistically different at T12h. IL-6 levels positively correlated with PRISM score in SSG patients at admission (p = 0.001; r = 0.86). Conclusion. PCT and IL-6 appear to be helpful in early assessment of pediatric sepsis, are of diagnostic value at admission, and are related to disease severity.  相似文献   

14.
1H NMR metabolic profiles of urine from sheep exposed to prenatal nutritional restriction (n = 19) and a control group with normal prenatal nutritional requirements (n = 19), followed by either conventional (n = 10 + 10) or high carbohydrate high fat postnatal diet (n = 9 + 9), were studied. Urine was sampled from 2, 6, 19 and 24-month-old animals receiving differential dietary treatments during the first 6 months and the same normal diet later. Principal component analysis of 1H NMR spectra (n = 164) showed a V-shaped metabolic trajectory as a function of age and diet, starting with urines with a high amount of glucose, indicative of monogastric-like metabolism, and exhibiting concomitant increase of metabolites related to rumen microflora (mainly glycine conjugates of benzoic and phenylacetic acid) as the ruminal metabolism developed. Urines from young (2-month-old) animals exposed to prenatal undernutrition followed by normal postnatal diet showed metabolic patters that are ahead in time on the metabolic trajectory relative to the prenatal control group. No long-term effects of fetal undernutrition, alone or in combination with postnatal hypernutrition were observed.  相似文献   

15.
Jyotsna Batra  Balaram Ghosh   《Genomics》2009,94(3):161-168
The chemokine (C–C motif) receptors (CCR) 2 and 5 are members of a large family of G protein-coupled receptors, playing important roles in asthma pathogenesis. Using standard sequencing techniques, a total of 15 single nucleotide and 8 insertion/deletion polymorphisms (DIPs) (5 novels) were identified in and around these two genes. None of the studied polymorphisms (N = 7, selected on the basis on linkage disequilibrium) was associated with asthma in a case (N = 315) – control (N = 337) study and showed no evidence for non-random transmission to individuals with asthma/atopy in Indian pedigrees (n = 235). However, multilocus haplotype analysis based on simulations yielded a P = 0.00005 in the case–control study and a P = 0.03 for the family-based association studies. Furthermore, rs3918356 and rs743660 polymorphisms in CCR2 were found to be associated with total serum IgE levels in both the study designs. Thus, our study supports a significant role for chemokine receptor polymorphisms in genetic susceptibility to asthma.  相似文献   

16.
Dzherelo (Immunoxel) and Anemin when combined with standard anti-tuberculosis therapy (ATT) were shown to produce better clinical outcome than chemotherapy alone. Sixty HIV-positive patients with active pulmonary TB were equally divided into three matched groups to receive either ATT, ATT + Dzherelo, or ATT + Dzherelo + Anemin. Peripheral blood samples were measured by ELISA for plasma levels of IL-2, IL-6, TNF-α, IFN-γ, and IFN-α. After 6 months of follow-up Dzherelo and Dzherelo + Anemin combinations produced 61% (P = 0.005) and 44.4% (P = 0.06) higher levels of IL-2, whereas in ATT group they were reduced by 33.1% (P = 0.002). The levels of IL-6 increased by 17% (P = 0.15) in ATT group, but declined in both immune intervention groups by 26.2% (P = 0.007) and 21.3% (P = 0.22). TNF-α was suppressed in two immunotherapy groups by 19.1% (P = 0.06) and 76.3% (P = 0.02), respectively, but had risen by 14% (P = 0.42) in ATT patients. The pattern of production of IFN-γ was opposite to that of TNF-α, but statistical significance was stronger in patients receiving ATT and Dzherelo + Anemin than in Dzherelo group: −34% (P = 0.004), +31.9% (P = 0.008), and +17.3% (P = 0.33), respectively. Moderately decreased levels of IFN-α were observed in all treatment arms (range 0.9–16.6%) but differences were not significant. Despite considerable intra-group variation in cytokine production, the baseline inter-group averages were not statistically different indicating that the results were not biased by sample heterogeneity. Immunomodulators used in this study possibly act by enhancing natural immune response against TB. Expanded study of other cytokines and correlates relevant to control and protection from TB and HIV is needed in order to identify biomarkers of favorable treatment outcome, which may aid design of better immune interventions and vaccines.  相似文献   

17.
The effectiveness of a rehabilitation program for reducing inter-dog aggression was evaluated at the municipal animal shelter. Sixteen dogs (of 60 examined) met the study criteria of medium inter-dog aggression as determined by an inter-dog aggression test. These dogs received a 10-day treatment of daily rehabilitation for 30 min (rehabilitation group, n = 9) or daily release into an outdoor enclosure for 30 min (control group, n = 7). Rehabilitation consisted of desensitising and counter-conditioning dogs to the approach of other “stimulus” dogs. Most dogs in the rehabilitation group showed a decline in aggression scores when re-tested after the last treatment (day 11), and differed significantly from the control dogs which showed either an increase or no change in aggression scores (U = 8.5, P < 0.01). Rehabilitation dogs also showed lower frequencies of aggressive body postures (“facing the stimulus dog”, P < 0.05, and “stiff posture”, P < 0.10) and higher frequencies of less assertive postures (“ears back”, P < 0.05, and “lowered neck”, P < 0.10) on day 11. The differences between groups were no longer significant when a reduced sample of dogs was tested 1 week after rehabilitation ended (day 18). The study shows short-term reduction of inter-dog aggression through rehabilitation, but further work is needed on effective ways of maintaining the behavioural change.  相似文献   

18.
The effect of two inorganic selenium forms has been investigated in the mycelia of Pleurotus ostreatus exposed to cadmium and silver salts in the shaken cultures. The degree of toxicity was assessed by the determination of malondialdehyde (MDA; a common biomarker of lipid peroxidation). The mycelia were exposed to one element form (up to 5 mg l−1) and also to the following combinations: cadmium(II) + selenium(IV); cadmium(II) + selenium(VI); silver(I) + selenium(IV); silver(I) + selenium(VI). The concentrations of cadmium, silver, selenium, and MDA were assessed in the mixed cytosol and cell membrane fractions (CCM). A positive correlation between MDA and cadmium was found in the CCM (β = 0.7775, P = 0.0001), whereas the effect of silver was less significant (β = 0.4642, P = 0.039). These results indicate that silver(I) and cadmium(II) have different capacities to induce lipid peroxidation in P. ostreatus. The protective role of selenium against metal-induced oxidative damage was found to be dependent on the oxidation state of the element form in the growth medium. The strongest beneficial effect was observed in mycelia exposed to cadmium(II) + selenium(IV) (inverse correlation between MDA and selenium in the CCM: β = −0.7129, P = 0.009) and it has been ascribed to a lower incorporation of the toxic metal and/or to possible intracellular interaction between selenium and cadmium. Under exposure to silver(I), the protective effect of selenium(IV) was less noticeable (correlation between MDA and selenium in the CCM; β = −0.6068, P = 0.036); in the presence of selenium(VI), no beneficial effect was observed.  相似文献   

19.
The aim of this study was to investigate the role of methylenetetrahydrofolate reductase (MTHFR) polymorphisms and MTHFR methylation pattern in cervical lesions development among women from Romania, a country with high prevalence of human papillomavirus (HPV) cervical infections. To achieve this goal, blood samples and cervical cytology specimens (n = 77)/tumour tissue specimens (n = 23) were investigated. As control, blood and negative cytological smears (n = 50) were used. A statistically significant association was found between T allele of C677T polymorphism and cervical lesions, heterozygote women presenting a threefold increased risk (normal/cervical lesions and tumours: wild homozygote 34/41 (0.68/0.41), heterozygote 14/51 (0.28/0.51), mutant homozygote 2/8 (0.04/0.08); OR = 3.081, P = 0.0035). Using χ square test for the control group, the HPV‐negative and HPV‐positive patients with cervix lesions, a significant correlation between viral infection and T allele of C677T polymorphism (P = 0.0287) was found. The MTHFR promoter was methylated in all HGSIL and tumour samples, significant differences being noted between HPV‐positive samples, control group and cases of cervical dysplastic lesions without HPV DNA (P < 0. 0001) and between samples from patients with high‐risk (hr)HPV versus low‐risk (lr)HPV (P = 0.0026). No correlations between polymorphisms and methylation were observed. In Romania, individuals carrying T allele are susceptible for cervical lesions. MTHFR promoter methylation is associated with cervical severity lesions and with hrHPV.  相似文献   

20.
The sister chromatid exchange (SCE) frequency, the cell-cycle progression analysis, and the single cell gel electrophoresis technique (SCGE, comet assay) were employed as genetic end-points to investigate the geno- and citotoxicity exerted by dicamba and one of its commercial formulation banvel® (dicamba 57.71%) on Chinese hamster ovary (CHO) cells. Log-phase cells were treated with 1.0–500.0 μg/ml of the herbicides and harvested 24 h later for SCE and cell-cycle progression analyses. All concentrations assessed of both test compounds induced higher SCE frequencies over control values. SCEs increased in a non-dose-dependent manner neither for the pure compound (r = 0.48; P > 0.05) nor for the commercial formulation (r = 0.58, P > 0.05). For the 200.0 μg/ml and 500.0 μg/ml dicamba doses and the 500.0 μg/ml banvel® dose, a significant delay in the cell-cycle progression was found. A regression test showed that the proliferation rate index decreased as a function of either the concentration of dicamba (r = −0.98, P < 0.05) or banvel® (r = −0.88, P < 0.01) titrated into cultures in the 1.0–500.0 μg/ml dose-range. SCGE performed on CHO cells after a 90 min pulse-treatment of dicamba and banvel® within a 50.0–500.0 μg/ml dose-range revealed a clear increase in dicamba-induced DNA damage as an enhancement of the proportion of slightly damaged and damaged cells for all concentrations used (P < 0.01); concomitantly, a decrease of undamaged cells was found over control values (P < 0.01). In banvel®-treated cells, a similar overall result was registered. Dicamba induced a significant increase both in comet length and width over control values (P < 0.01) regardless of its concentration whereas banvel® induced the same effect only within 100.0–500.0 μg/ml dose range (P < 0.01). As detected by three highly sensitive bioassays, the present results clearly showed the capability of dicamba and banvel® to induce DNA and cellular damage on CHO cells.  相似文献   

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