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41.
Vanadium is a metal whose toxicity towards terrestrial and aquatic species has been under-reported to date.. The biochemical responses of vanadium in amphibian species have not been determined. To establish the effects of vanadium (V) on exposed adult Xenopus laevis, acute and chronic exposures were conducted, and biomarker analyses were performed on liver and muscle tissues from exposed frogs. Biomarkers of exposure, such as acetylcholinesterase (AChE) and metallothioneins (MT), were analysed. Biomarkers of effect were also analysed to determine possible increases in reactive oxygen species (ROS), and the effect of the exposure on the energy balance in the organisms. These included superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH), protein carbonyls (PC), malondialdehyde (MDA), and cellular energy allocation (CEA) (energy available, energy consumption, lipids, proteins and glucose). In acute exposures, the energy balances in organisms were distinctly affected, possibly due to insulin mimetic properties of V. In chronic exposures, MT, AChE, SOD, CAT and GSH responses were more pronounced. Although AChE is generally inhibited by pollutant exposure, in this study, it was stimulated. There were significant inhibitions of SOD and CAT, previously observed in frog species. PC levels increased in the highest acute exposure concentration, indicating protein damage. The IBR.v2 revealed the biochemical responses of V more effectively than traditional statistical analysis. 相似文献
42.
Juveniles of the shrimp Litopenaeus vannamei (3.3 ± 0.4 g) were exposed separately to nitrite (0.0, 1.1, 2.6, and 5.3 mg/L nitrogen as nitrite [NO2−-N]) and nitrate (0, 90, 225 and 400 mg/L nitrogen as nitrate [NO3−-N]) concentrations equivalent to 0, 10, 25, and 50% of the LC50-96 h value of NO2−-N and NO3−-N in low salinity water (3 g/L). Shrimps responded to nitrite and nitrate according to changes in oxyhemocyanin, glucose, lactate and ion levels in the hemolymph after 6, 12, 24, and 48 h of exposure. Oxyhemocyanin levels decreased with increasing nitrite and nitrate levels and were higher at 50% exposure to the contaminants. Compared to the control, glucose and lactate increased significantly at 50% exposure to nitrite and nitrate, particularly at 12 and 24 h. Na+ in the hemolymph changed with nitrite and nitrate, while K+ only changed ˜with nitrite. 相似文献
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44.
ObjectivesCompare single-leg aerobic capacity and strength differences between the surgically repaired ACL leg (injured) and the uninjured leg.DesignCross-sectional study.SettingLaboratory.ParticipantsEight participants (5 female, 3 male, age = 23 ± 3.5 y, mass = 72.3 ± 17.3 kg, height = 169.7 ± 9.4 cm) that returned to play from ACL surgery between six and 18 months.Main outcome measuresParticipants performed an aerobically-based, single-leg cycling protocol to determine maximum oxygen consumption, ventilatory threshold, heart rate, rating of perceived exertion, and maximal watts cycled. Participants also performed isokinetic knee flexion and extension on a dynamometer to assess peak torque, total work, work fatigue, and power.ResultsThere were no statistical differences in single-leg aerobic capacity or strength outcomes between the injured and uninjured legs.ConclusionsIndividuals who have had an ACL surgically repaired six to 18 months after return to play do not appear to have aerobic capacity or strength deficits between the injured leg and uninjured leg. 相似文献
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47.
《Respiratory investigation》2022,60(3):434-437
We present the case of a bedridden elderly patient who demonstrated dramatic improvement in innominate artery compression syndrome with postural changes alone. A 94-year-old woman presented with dyspnea. Physical findings revealed stridor in the right-sided decubitus position. Her symptoms did not improve with conventional asthma treatment. Plain computed tomography revealed tracheal compression by the bent innominate artery. Contrast-enhanced computed tomography with postural changes altered the compression sites of the organs, resolving the tracheal stenosis. The number of similar bedridden elderly patients will increase in an aging society. We report this case to aid physicians in managing such patients. 相似文献
48.
《Clinical nutrition (Edinburgh, Scotland)》2022,41(10):2356-2363
Background & aimsTo date, the literature examining the effects of whole-egg consumption on health outcomes focuses primarily on cardiovascular health markers; however, a significant gap exists in the literature about how egg consumption may influence body composition indicators. The aim of this study was to estimate the association between egg consumption and body composition indicators and to examine whether this relationship is mediated by protein intake in young adults.MethodsA cross-sectional study was conducted involving 355 first-year university students (aged 18–30 years) from a Spanish public university. Body composition was measured using bioimpedance and dual-energy X-ray absorptiometry (DXA) and fitness components were determined using the course-navette test. Egg consumption and protein intake (both in g/day/kg of body weight) were determined using a 137-item Food-Frequency Questionnaire. ANCOVA models were used to test the mean differences in body composition indicators (body mass index [BMI], ratio waist circumference/height [WC/height], body fat mass percentage, and body lean mass percentage) by egg consumption categories (<1 egg/week, 1–4 eggs/week, ≥5 eggs/week). Hayes's PROCESS macro was used for mediation analyses.ResultsParticipants reporting high egg consumption (≥5 eggs/week) showed significantly lower BMI, WC/height and body fat mass percentage values and higher body lean mass percentage values than those reporting low egg consumption (<1 egg/week) (p < 0.05). However, these relationships were not maintained after adjusting for protein intake. Protein intake acted as a full mediator of the relationships of egg consumption with BMI (indirect effect [IE] = ?1.19; 95% CI [?3.33; ?0.36]), WC/height (IE = ?0.01; 95% CI [?0.04; ?0.01]) and body lean mass percentage (IE = 2.99; 95% CI [1.26; 5.73]) as a partial mediator of the relationship be-tween egg consumption and body fat mass percentage (IE = ?2.19; 95% CI [?4.92; ?0.46]).ConclusionsThe association between egg consumption and body composition is mediated by protein intake. This finding is important from a public health perspective, suggesting that higher egg consumption (≥5 eggs/week) may lead to a healthier body composition, especially due to higher protein intake. 相似文献
49.
Fang Xing Xin Fang Xiang-Dan Gong Xin Zhao Ying Du Zheng-Liang Ma Xiao-Ping Gu Tian-Jiao Xia 《中国神经再生研究》2020,(6):1094-1101
Sleep-wake rhythm disturbances,which are characterized by abnormal sleep timing or duration,are associated with cognitive dysfunction.Photoacoustic treatments including light and sound stimulation have been found to be effective in modulating sleep patterns and improving cognitive behavior in abnormal sleep-wake pattern experiments.In this study,we examined whether light and sound interventions could reduce sleep-wake pattern disturbances and memory deficits in a sleep rhythm disturbance model.We established a model of sleep rhythm disturbance in C57 BL/6 J mice via a sleep deprivation method involving manual cage tapping,cage jostling,and nest disturbance.We used a Mini Mitter radio transmitter device to monitor motor activity in the mice and fear conditioning tests to assess cognitive function.Our results indicated that an intervention in which the mice were exposed to blue light(40-Hz flickering frequency)for 1 hour during their subjective daytime significantly improved the 24-hour-acrophase shift and reduced the degree of memory deficit induced by sleep deprivation.However,interventions in which the mice were exposed to a 40-Hz blue light at offset time or subjective night time points,as well as 2 Hz-blue light at 3 intervention time points(subjective day time,subjective night time,and offset time points),had no positive effects on circadian rhythm shift or memory deficits.Additionally,a 2000-Hz sound intervention during subjective day time attenuated the24-hour-acrophase shift and memory decline,while 440-Hz and 4000-Hz sounds had no effect on circadian rhythms.Overall,these results demonstrate that photoacoustic treatment effectively corrected abnormal sleep-wake patterns and cognitive dysfunction associated with sleep-deprivation-induced disturbances in sleep-wake rhythm.All animal experiments were approved by the Experimental Animal Ethics Committee of Drum Tower Hospital Affiliated to the Medical College of Nanjing University,China(approval No.20171102)on November20,2017. 相似文献