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Effects of Enteromorpha prolifera polysaccharides on growth performance,intestinal barrier function and cecal microbiota in yellow-feathered broilers under heat stress
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作者 Wenchao Liu Huimei Liu +3 位作者 Yaoyao Wang Zhongxiang Zhao Balamuralikrishnan Balasubramanian Rajesh Jha 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期344-361,共18页
Background Global warming leading to heat stress(HS)is becoming a major challenge for broiler production.This study aimed to explore the protective effects of seaweed(Enteromorpha prolifera)polysaccharides(EPS)on the ... Background Global warming leading to heat stress(HS)is becoming a major challenge for broiler production.This study aimed to explore the protective effects of seaweed(Enteromorpha prolifera)polysaccharides(EPS)on the intestinal barrier function,microbial ecology,and performance of broilers under HS.A total of 144 yellow-feathered broilers(male,56 days old)with 682.59±7.38 g were randomly assigned to 3 groups:1)TN(thermal neutral zone,23.6±1.8℃),2)HS(heat stress,33.2±1.5℃ for 10 h/d),and 3)HSE(HS+0.1%EPS).Each group contained 6 replicates with 8 broilers per replicate.The study was conducted for 4 weeks;feed intake and body weights were measured at the end of weeks 2 and 4.At the end of the feeding trial,small intestine samples were collected for histomorphology,antioxidant,secretory immunoglobulin A(s Ig A)content,apoptosis,gene and protein expression analysis;cecal contents were also collected for microbiota analysis based on 16S r DNA sequencing.Results Dietary EPS promoted the average daily gain(ADG)of broilers during 3–4 weeks of HS(P<0.05).At the end of HS on broilers,the activity of total superoxide dismutase(T-SOD),glutathione S-transferase(GST),and the content of s Ig A in jejunum were improved by EPS supplementation(P<0.05).Besides,dietary EPS reduced the epithelial cell apoptosis of jejunum and ileum in heat-stressed broilers(P<0.05).Addition of EPS in HS group broilers'diet upregulated the relative m RNA expression of Occludin,ZO-1,γ-GCLc and IL-10 of the jejunum(P<0.05),whereas downregulated the relative m RNA expression of NF-κB p65,TNF-αand IL-1βof the jejunum(P<0.05).Dietary EPS increased the protein expression of Occludin and ZO-1,whereas it reduced the protein expression of NF-κB p65 and MLCK(P<0.01)and tended to decrease the protein expression of TNF-α(P=0.094)in heat-stressed broilers.Furthermore,the proportions of Bacteroides and Oscillospira among the three groups were positively associated with jejunal apoptosis and pro-inflammatory cytokine expression(P<0.05)and negatively correlated with jejunal Occludin level(P<0.05).However,the proportions of Lactobacillus,Barnesiella,Subdoligranulum,Megasphaera,Collinsella,and Blautia among the three groups were positively related to ADG(P<0.05).Conclusions EPS can be used as a feed additive in yellow-feathered broilers.It effectively improves growth performance and alleviates HS-induced intestinal injury by relieving inflammatory damage and improving the tight junction proteins expression.These beneficial effects may be related to inhibiting NF-κB/MLCK signaling pathway activation and regulation of cecal microbiota. 展开更多
关键词 BROILERS Cecal microbiota Heat stress Intestinal barrier function Seaweed polysaccharides
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Effects of Tongluo Jiedu prescription on immune function and oxidative stress in patients with oral cancer
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作者 Yue Yin Yuan Yao +2 位作者 Yi-Jie Li Li-Li Zhao Qiang Zhang 《World Journal of Clinical Cases》 SCIE 2024年第17期3045-3052,共8页
BACKGROUND Oral cancer,which is caused by mucous membrane variation,represents a prevalent malignant tumor in the oral and maxillofacial region,posing a significant threat to patients’lives and safety.While surgical ... BACKGROUND Oral cancer,which is caused by mucous membrane variation,represents a prevalent malignant tumor in the oral and maxillofacial region,posing a significant threat to patients’lives and safety.While surgical intervention stands as a cornerstone treatment for oral cancer patients,it carries the risk of incomplete treatment or high rates of postoperative recurrence.Hence,a multifaceted approach incorporating diverse treatment modalities is essential to enhance patient prognosis.AIM To analyze the application effect of Tongluo Jiedu prescription as adjuvant therapy and its influence on patient prognosis in patients with oral cancer.METHODS Eighty oral cancer patients in our hospital were selected and divided into the observation group and control group by a random number table.The control group was treated with continuous arterial infusion chemotherapy of cisplatin and 5-fluorouracil.The observation group was additionally given Tongluo Jiadu prescription.The inflammatory stress level,peripheral blood T-cell subsets,and immune function of the two groups were subsequently observed.SPSS 21.0 was used for data analysis.RESULTS The observation group demonstrated lower levels of interleukin-6 and C-reactive protein,and a higher level of tumor necrosis factor in comparison to the control group.After treatment,the immune function in the observation group was significantly better than in the control group.CONCLUSION Tongluo Jiedu prescription can improve the immune function and oxidative stress level of patients with oral cancer and accelerate the recovery process. 展开更多
关键词 Tongluo Jiedu prescription Oral cancer patients Immune function Oxidative stress
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Impact of minimally invasive surgery on immune function and stress response in gastric cancer patients
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作者 Rong-Hua Zhu Peng-Cheng Li +1 位作者 Jie Zhang Hua-Hua Song 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第8期2484-2493,共10页
BACKGROUND Gastric cancer remains a leading cause of cancer-related mortality globally.Traditional open surgery for gastric cancer is often associated with significant morbidity and prolonged recovery.AIM To evaluate ... BACKGROUND Gastric cancer remains a leading cause of cancer-related mortality globally.Traditional open surgery for gastric cancer is often associated with significant morbidity and prolonged recovery.AIM To evaluate the effectiveness of laparoscopic minimally invasive surgery as an alternative to traditional open surgery for gastric cancer,focusing on its potential to reduce trauma,accelerate recovery,and achieve comparable oncological out-comes.METHODS This study retrospectively analyzed 203 patients with gastric cancer who underwent surgery at the Shanghai Health Medical College Affiliated Chongming Hospital from January 2020 to December 2023.The patients were divided into two groups:Minimally invasive surgery group(n=102),who underwent laparoscopic gastrectomy,and open surgery group(n=101),who underwent traditional open gastrectomy.We compared surgical indicators(surgical incision size,intraop-erative blood loss,surgical duration,and number of lymph nodes dissected),recovery parameters(time to first flatus,time to start eating,time to ambulation,and length of hospital stay),immune function(levels of IgA,IgG,and IgM),intestinal barrier function(levels of D-lactic acid and diamine oxidase),and stress response(levels of C-reactive protein,interleukin-6,and procalcitonin).RESULTS The minimally invasive surgery group demonstrated significantly better outcomes in terms of surgical indicators,including smaller incisions,less blood loss,shorter surgery time,and more lymph nodes dissected(P<0.05 for all).Recovery was also faster in the minimally invasive surgery group,with earlier return of bowel function,earlier initiation of diet,quicker mobilization,and shorter hospital stays(P<0.05 for all).Furthermore,patients in the minimally invasive surgery group had better preserved immune function,superior intestinal barrier function,and a less pronounced stress response postoperatively(P<0.05 for all).CONCLUSION Laparoscopic minimally invasive surgery for gastric cancer not only provides superior surgical indicators and faster recovery but also offers advantages in preserving immune function,protecting intestinal barrier function,and mitigating the stress response compared to traditional open surgery.These findings support the broader adoption of laparoscopic techniques in the management of gastric cancer. 展开更多
关键词 Gastric cancer Laparoscopic surgery Minimally invasive surgery Immune function Intestinal barrier stress response
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Overexpression of the transcription factor MdWRKY115 improves drought and osmotic stress tolerance by directly binding to the MdRD22 promoter in apple 被引量:1
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作者 Qinglong Dong Yi Tian +9 位作者 Xuemei Zhang Dingyue Duan He Zhang Kaiyu Yang Peng Jia Haoan Luan Suping Guo Guohui Qi Ke Mao Fengwang Ma 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第3期629-640,共12页
Abiotic stress reduces plant yield and quality.WRKY transcription factors play key roles in abiotic stress responses in plants,but the molecular mechanisms by which WRKY transcription factors mediate responses to drou... Abiotic stress reduces plant yield and quality.WRKY transcription factors play key roles in abiotic stress responses in plants,but the molecular mechanisms by which WRKY transcription factors mediate responses to drought and osmotic stresses in apple(Malus×domestica Borkh.)remain unclear.Here,we functionally characterized the apple GroupⅢWRKY gene MdWRKY115.qRT-PCR analysis showed that MdWRKY115 expression was up-regulated by drought and osmotic stresses.GUS activity analysis revealed that the promoter activity of MdWRKY115 was enhanced under osmotic stress.Subcellular localization and transactivation assays indicated that MdWRKY115 was localized to the nucleus and had a transcriptional activity domain at the N-terminal region.Transgenic analysis revealed that the overexpression of MdWRKY115 in Arabidopsis plants and in apple callus markedly enhanced their tolerance to drought and osmotic stresses.DNA affinity purification sequencing showed that MdWRKY115 binds to the promoter of the stress-related gene MdRD22.This binding was further verified by an electrophoretic mobility shift assay.Collectively,these findings suggest that MdWRKY115 is an important regulator of osmotic and drought stress tolerance in apple. 展开更多
关键词 APPLE MdWRKY115 Osmotic stress Drought stress function analysis
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Mechanisms of autophagy function and regulation in plant growth,development,and response to abiotic stress
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作者 Yongbo Li Xiangmin Xu +5 位作者 Guang Qi Dezhou Cui Chen Huang Xinxia Sui Genying Li Qingqi Fan 《The Crop Journal》 SCIE CSCD 2023年第6期1611-1625,共15页
Autophagy is an evolutionarily conserved degradation pathway of lysosomes(in mammals)and vacuoles(in yeasts and plants)from lower yeasts to higher mammals.It wraps unwanted organelles and damaged proteins in a double-... Autophagy is an evolutionarily conserved degradation pathway of lysosomes(in mammals)and vacuoles(in yeasts and plants)from lower yeasts to higher mammals.It wraps unwanted organelles and damaged proteins in a double-membrane structure to transport them to vacuoles for degradation and recycling.In plants,autophagy functions in adaptation to the environment and maintenance of growth and development.This review systematically describes the autophagy process,biological functions,and regulatory mechanisms occurring during plant growth and development and in response to abiotic stresses.It provides a basis for further theoretical research and guidance of agricultural production. 展开更多
关键词 AUTOPHAGY function Mechanism DEVELOPMENT Abiotic stresses
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Multifaceted regulatory functions of CsBPC2 in cucumber under salt stress conditions
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作者 Shuzhen Li Mintao Sun +8 位作者 Li Miao Qinghua Di Lijun Lv Xianchang Yu Yan Yan Chaoxing He Jun Wang Aokun Shi Yansu Li 《Horticulture Research》 SCIE CSCD 2023年第5期126-138,共13页
BASIC PENTACYSTEINE(BPC)transcription factors are essential regulators of plant growth and development.However,BPC functions and the related molecular mechanisms during cucumber(Cucumis sativus L.)responses to abiotic... BASIC PENTACYSTEINE(BPC)transcription factors are essential regulators of plant growth and development.However,BPC functions and the related molecular mechanisms during cucumber(Cucumis sativus L.)responses to abiotic stresses,especially salt stress,remain unknown.We previously determined that salt stress induces CsBPC expression in cucumber.In this study,Csbpc2 transgene-free cucumber plants were created using a CRISPR/Cas9-mediated editing system to explore CsBPC functions associated with the salt stress response.The Csbpc2 mutants had a hypersensitive phenotype,with increased leaf chlorosis,decreased biomass,and increased malondialdehyde and electrolytic leakage levels under salt stress conditions.Additionally,a mutated CsBPC2 resulted in decreased proline and soluble sugar contents and antioxidant enzyme activities,which led to the accumulation of hydrogen peroxide and superoxide radicals.Furthermore,the mutation to CsBPC2 inhibited salinity-induced PM-H+-ATPase and V-H+-ATPase activities,resulting in decreased Na+efflux and increased K+efflux.These findings suggest that CsBPC2 may mediate plant salt stress resistance through its effects on osmoregulation,reactive oxygen species scavenging,and ion homeostasis-related regulatory pathways.However,CsBPC2 also affected ABA signaling.The mutation to CsBPC2 adversely affected salt-induced ABA biosynthesis and the expression of ABA signaling-related genes.Our results indicate that CsBPC2 may enhance the cucumber response to salt stress.It may also function as an important regulator of ABA biosynthesis and signal transduction.These findings will enrich our understanding of the biological functions of BPCs,especially their roles in abiotic stress responses,thereby providing the theoretical basis for improving crop salt tolerance. 展开更多
关键词 CRISPR/Cas9 stress functionS
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Maternal stress exposure during pregnancy impairs ultrastructural changes in the white matter and reduces cognitive function in offspring mice
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作者 CHENG Yan GUO Jian-wei +1 位作者 ZHU Bing YI Min-min 《Journal of Hainan Medical University》 CAS 2023年第16期7-15,共9页
Objective:To explore whether maternal stress exposure during pregnancy impairs cognitive function and white matter ultrastructure in offspring mice.Methods:The parent rats were divided into two groups:pressure exposur... Objective:To explore whether maternal stress exposure during pregnancy impairs cognitive function and white matter ultrastructure in offspring mice.Methods:The parent rats were divided into two groups:pressure exposure group(group PE)and control group(group C),and the positive date of vaginal smear of female SD rats was day 0 of gestation.Female mice in group PE were exposed to binding pressure(3 times/day)on day 14-20 of gestation for 45 min-1 h/time.Behavioral tests(Morris water maze and Y maze)were performed on 1-month-old offspring mice followed by cardiac perfusion of fixed brain specimens and placement in mixed fixative solution.The total volume of white matter,total length and volume of myelinated nerve fibers and total length and volume of myelin sheath were calculated using modern stereoscopic methods,and the inner and outer diameter and inner and outer circumference of the myelin sheath were analyzed.Results:1)Behavioral tests:compared with the group C,the average latency of the 3th and 4th day in the group PE were significantly prolonged,the percentage of the resting time in the quadrant of the platform and the frequency of acrossing the effective area of platform in the fifth day of space exploration experiment were significantly reduced of Morris water maze test,and visiting distance,duration and numbers in novel arm significantly increased of Y-maze test(P<0.05).2)Compared with group C,the total volume of white matter,total length of myelinated nerve fibers,total volume of myelinated nerve fibers and myelin sheath in the group PE were significantly reduced(P<0.05),the inner diameter and outer diameter of myelin sheath decreased significantly(P<0.05),and the inner perimeter,outer perimeter and inner and outer perimeter differences increased significantly(P<0.05).3)There was a correlation between behavioral test results and white matter ultrastructure measurement results.Conclusions:Maternal stress exposure during pregnancy could impair the cognitive function and white matter and its ultrastructure in the offspring,and there was a correlation between decreased cognitive function and white matter damages. 展开更多
关键词 Mental stress exposure Cognitive function White matter of the brain Morris water maze Y maze
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Research progress on the effects of positive stress reduction on positive awareness and psychosocial functioning in patients with depressive disorders
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作者 Yanping Li Rui Li +3 位作者 Guangmei Gong Fan Zhang Changliang Ji Fangde Cai 《Journal of Translational Neuroscience》 2023年第4期12-16,共5页
To review the current research status of positive thought stress reduction therapy(PTSRT),psychosocial functioning of patients with depressive disorders,the shortcomings and outlook of the influence of PTSRT on positi... To review the current research status of positive thought stress reduction therapy(PTSRT),psychosocial functioning of patients with depressive disorders,the shortcomings and outlook of the influence of PTSRT on positive thought awareness,and psychosocial functioning of patients with depressive disorders.This review has the objective to provide clinical healthcare personnel with essential information about the use of PTSRT to improve the level of positive thought and psychosocial functioning of patients with depressive disorders. 展开更多
关键词 positive stress reduction depressive disorders positive awareness psychosocial functioning
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Elevated brain temperature under severe heat exposure impairs cortical motor activity and executive function
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作者 Xiang Ren Tan Mary C.Stephenson +4 位作者 Sharifah Badriyah Alhadad Kelvin W.Z.Loh Tuck Wah Soong Jason K.W.Lee Ivan C.C.Low 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第2期233-244,共12页
Background:Excessive heat exposure can lead to hyperthermia in humans,which impairs physical performance and disrupts cognitive function.While heat is a known physiological stressor,it is unclear how severe heat stres... Background:Excessive heat exposure can lead to hyperthermia in humans,which impairs physical performance and disrupts cognitive function.While heat is a known physiological stressor,it is unclear how severe heat stress affects brain physiology and function.Methods:Eleven healthy participants were subjected to heat stress from prolonged exercise or warm water immersion until their rectal temperatures(T_(re))attained 39.5℃,inducing exertional or passive hyperthermia,respectively.In a separate trial,blended ice was ingested before and during exercise as a cooling strategy.Data were compared to a control condition with seated rest(normothermic).Brain temperature(T_(br)),cerebral perfusion,and task-based brain activity were assessed using magnetic resonance imaging techniques.Results:T_(br)in motor cortex was found to be tightly regulated at rest(37.3℃±0.4℃(mean±SD))despite fluctuations in T_(re).With the development of hyperthermia,T_(br)increases and dovetails with the rising T_(re).Bilateral motor cortical activity was suppressed during high-intensity plantarflexion tasks,implying a reduced central motor drive in hyperthermic participants(T_(re)=38.5℃±0.1℃).Global gray matter perfusion and regional perfusion in sensorimotor cortex were reduced with passive hyperthermia.Executive function was poorer under a passive hyperthermic state,and this could relate to compromised visual processing as indicated by the reduced activation of left lateral-occipital cortex.Conversely,ingestion of blended ice before and during exercise alleviated the rise in both T_(re)and T_(bc)and mitigated heat-related neural perturbations.Conclusion:Severe heat exposure elevates T_(br),disrupts motor cortical activity and executive function,and this can lead to impairment of physical and cognitive performance. 展开更多
关键词 Brain functional activity COGNITION Heat stress HYPERTHERMIA Motor function
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Hypidone hydrochloride(YL-0919)ameliorates functional deficits after traumatic brain injury in mice by activating the sigma-1 receptor for antioxidation
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作者 Yafan Bai Hui Ma +5 位作者 Yue Zhang Jinfeng Li Xiaojuan Hou Yixin Yang Guyan Wang Yunfeng Li 《Neural Regeneration Research》 SCIE CAS 2025年第8期2325-2336,共12页
Traumatic brain injury involves complex pathophysiological mechanisms,among which oxidative stress significantly contributes to the occurrence of secondary injury.In this study,we evaluated hypidone hydrochloride(YL-0... Traumatic brain injury involves complex pathophysiological mechanisms,among which oxidative stress significantly contributes to the occurrence of secondary injury.In this study,we evaluated hypidone hydrochloride(YL-0919),a self-developed antidepressant with selective sigma-1 receptor agonist properties,and its associated mechanisms and targets in traumatic brain injury.Behavioral experiments to assess functional deficits were followed by assessment of neuronal damage through histological analyses and examination of blood-brain barrier permeability and brain edema.Next,we investigated the antioxidative effects of YL-0919 by assessing the levels of traditional markers of oxidative stress in vivo in mice and in vitro in HT22 cells.Finally,the targeted action of YL-0919 was verified by employing a sigma-1 receptor antagonist(BD-1047).Our findings demonstrated that YL-0919 markedly improved deficits in motor function and spatial cognition on day 3 post traumatic brain injury,while also decreasing neuronal mortality and reversing blood-brain barrier disruption and brain edema.Furthermore,YL-0919 effectively combated oxidative stress both in vivo and in vitro.The protective effects of YL-0919 were partially inhibited by BD-1047.These results indicated that YL-0919 relieved impairments in motor and spatial cognition by restraining oxidative stress,a neuroprotective effect that was partially reversed by the sigma-1 receptor antagonist BD-1047.YL-0919 may have potential as a new treatment for traumatic brain injury. 展开更多
关键词 antidepressant drug blood-brain barrier cognitive function hypidone hydrochloride(YL-0919) neurological function nuclear factor-erythroid 2 related factor 2 oxidative stress sigma-1 receptor superoxide dismutase traumatic brain injury
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Size-dependent thermomechanical vibration characteristics of rotating pre-twisted functionally graded shear deformable microbeams
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作者 Songye JIN Bo ZHANG +4 位作者 Wuyuan ZHANG Yuxing WANG Huoming SHEN Jing WANG Juan LIU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第6期1015-1032,共18页
A three-dimensional(3D)thermomechanical vibration model is developed for rotating pre-twisted functionally graded(FG)microbeams according to the refined shear deformation theory(RSDT)and the modified couple stress the... A three-dimensional(3D)thermomechanical vibration model is developed for rotating pre-twisted functionally graded(FG)microbeams according to the refined shear deformation theory(RSDT)and the modified couple stress theory(MCST).The material properties are assumed to follow a power-law distribution along the chordwise direction.The model introduces one axial stretching variable and four transverse deflection variables including two pure bending components and two pure shear ones.The complex modal analysis and assumed mode methods are used to solve the governing equations of motion under different boundary conditions(BCs).Several examples are presented to verify the effectiveness of the developed model.By coupling the slenderness ratio,gradient index,rotation speed,and size effect with the pre-twisted angle,the effects of these factors on the thermomechanical vibration of the microbeam with different BCs are investigated.It is found that with the increase in the pre-twisted angle,the critical slenderness ratio and gradient index corresponding to the thermal instability of the microbeam increase,while the critical material length scale parameter(MLSP)and rotation speed decrease.The sensitivity of the fundamental frequency to temperature increases with the increasing slenderness ratio and gradient index,and decreases with the other increasing parameters.Moreover,the size effect can suppress the dynamic stiffening effect and enhance the Coriolis effect.Finally,the mode transition is quantitatively demonstrated by a modal assurance criterion(MAC). 展开更多
关键词 thermomechanical vibration rotating pre-twisted functionally graded(FG)microbeam refined shear deformation theory(RSDT) modified couple stress theory(MCST) modal assurance criterion(MAC)
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L-Arginine Supplementation Mitigates Dichlorvos-Induced Haematocardiotoxicity, and Oxidative Stress in Male Wistar Rats
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作者 Waidi Adeoye Saka Yusuff Dimeji Igbayilola +6 位作者 Jabba Hamidu Lawan Taoheed Kolawole Muftaudeen Ridwanullahi Adejumo Tolulope Deborah Alu Mary Ikuomola Joshua Tinuade Ojelere Victor Odufa Adegoke 《Open Journal of Applied Sciences》 2024年第7期1886-1903,共18页
Due to its toxicity, dichlorvos—a common organophosphate pesticide—poses significant risks to human health. This study utilized male Wistar rats to explore the potential protective effects of L-arginine supplementat... Due to its toxicity, dichlorvos—a common organophosphate pesticide—poses significant risks to human health. This study utilized male Wistar rats to explore the potential protective effects of L-arginine supplementation against dichlorvos-induced toxicity, focusing on cardiotoxicity, haematotoxicity and oxidative stress. The rats were divided into four groups: Control, L-arginine (L), Dichlorvos (D), and L-arginine + Dichlorvos (L + D). Dichlorvos was administered to the D group, L-arginine (100 mg/kg) to the L group, and both L-arginine and dichlorvos to the L + D group. The study evaluated various parameters, including cardiovascular, oxidative stress markers, and haematological indices. Significant changes in haematological parameters such as haemoglobin (Hb), haematocrit (HCT), and red blood cell count (RBC) indicated haematotoxicity after dichlorvos administration. Additionally, elevated cardiac markers, including lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB), suggested cardiotoxic effects. Exposure to dichlorvos also resulted in decreased antioxidant enzyme levels and increased oxidative stress indicators like malondialdehyde (MDA). Remarkably, L-arginine supplementation mitigated the damage caused by dichlorvos. It normalized the altered haematological parameters, demonstrating its protective effect against haematotoxicity. The rise in cardiac markers was reduced with L-arginine supplementation, indicating protection against cardiotoxicity. Moreover, L-arginine significantly decreased oxidative stress, as evidenced by lower MDA levels and restored antioxidant enzyme activity. In conclusion, L-arginine supplementation in male Wistar rats showed promising protective effects against dichlorvos-induced cardiotoxicity, haematotoxicity and oxidative stress. This suggests that L-arginine may offer a beneficial intervention to mitigate the adverse effects of dichlorvos on blood and heart health, paving the way for potential treatments for pesticide poisoning. 展开更多
关键词 DICHLORVOS L-ARGININE Cardiovascular function Haematological Parameters Oxidative stress
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SCATTERING OF HARMONIC ANTI-PLANE SHEAR STRESS WAVES BY A CRACK IN FUNCTIONALLY GRADED PIEZOELECTRIC/PIEZOMAGNETIC MATERIALS 被引量:6
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作者 Liang Jun 《Acta Mechanica Solida Sinica》 SCIE EI 2007年第1期75-86,共12页
In this paper, the dynamic behavior of a permeable crack in functionally graded piezoelectric/piezomagnetic materials is investigated. To make the analysis tractable, it is assumed that the material properties vary ex... In this paper, the dynamic behavior of a permeable crack in functionally graded piezoelectric/piezomagnetic materials is investigated. To make the analysis tractable, it is assumed that the material properties vary exponentially with the coordinate parallel to the crack. By using the Fourier transform, the problem can be solved with the help of a pair of dual integral equations in which the unknown is the jump of displacements across the crack surfaces. These equations are solved to obtain the relations between the electric filed, the magnetic flux field and the dynamic stress field near the crack tips using the Schmidt method. Numerical examples are provided to show the effect of the functionally graded parameter and the circular frequency of the incident waves upon the stress, the electric displacement and the magnetic flux intensity factors of the crack. 展开更多
关键词 functionally graded piezoelectric/piezomagnetic materials CRACK stress wave
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THERMAL STRESSES RELAXATION DESIGN OF Ni/NiFe_(2)O_(4) SYSTEM FUNCTIONALLY GRADED CERMET INERT ANODE 被引量:4
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作者 J. Li Q.S. Zhang Y.Q. Lai S.L. Ye Y.X. Liu 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2005年第5期635-641,共7页
The thermal stresses relaxation of Ni/NiFe2O4 system functionally graded cermet inert anode for aluminum electrolysis was optimally designed. The transient thermal stresses of the inert anode under complex boundary co... The thermal stresses relaxation of Ni/NiFe2O4 system functionally graded cermet inert anode for aluminum electrolysis was optimally designed. The transient thermal stresses of the inert anode under complex boundary condition during high-temp (955℃) electrolysis were calculated using the finite-element software ANSYS, the influence of different parameters on the distribution of the thermal stresses were analyzed. The results showed that, during the process of thermal shock, the thermal hoop tensile stress on the surface of the anode is very large, which is possibly the major cause of anode crack; when the radius of the anode is between 0.05-0.15m, a range that can be realized by recent manufacturing technology, the optimum composition distribution exponent p is 0.25; The hoop tensile stresses reduce with the decrease of anode scale and also decrease with the decrease of the convection coefficient between the electrolyte and the anode. 展开更多
关键词 functionally graded material (FGM) transient thermal stresses ANSYS inert anode aluminum electrolysis
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Stress analysis of functionally graded rotating discs: analytical and numerical solutions 被引量:3
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作者 Hasan Callioglu Numan Behll Bektas Metin Sayer 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第6期950-955,共6页
This study deals with stress analysis of annular rotating discs made of functionally graded materials(FGMs).Elasticity modulus and density of the discs are assumed to vary radially according to a power law function,... This study deals with stress analysis of annular rotating discs made of functionally graded materials(FGMs).Elasticity modulus and density of the discs are assumed to vary radially according to a power law function,but the material is of constant Poisson's ratio.A gradient parameter n is chosen between 0 and 1.0.When n = 0,the disc becomes a homogeneous isotropic material.Tangential and radial stress distributions and displacements on the disc are investigated for various gradient parameters n by means of the diverse elasticity modulus and density by using analytical and numerical solutions.Finally,a homogenous tangential stress distribution and the lowest radial stresses along the radius of a rotating disc are approximately obtained for the gradient parameter n = 1.0 compared with the homogeneous,isotropic case n = 0.This means that a disc made of FGMs has the capability of higher angular rotations compared with the homogeneous isotropic disc. 展开更多
关键词 functional graded materials stress analysis Analytical analysis Finite element analysis (FEA)
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SCATTERING OF THE HARMONIC STRESS WAVE BY CRACKS IN FUNCTIONALLY GRADED PIEZOELECTRIC MATERIALS 被引量:2
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作者 Ma Li Nie Wu +1 位作者 Wu Linzhi Zhou Zhengong 《Acta Mechanica Solida Sinica》 SCIE EI 2005年第4期295-301,共7页
The present paper considers the scattering of the time harmonic stress wave by a single crack and two collinear cracks in functionally graded piezoelectric material (FGPM). It is assumed that the properties of the F... The present paper considers the scattering of the time harmonic stress wave by a single crack and two collinear cracks in functionally graded piezoelectric material (FGPM). It is assumed that the properties of the FGPM vary continuously as an exponential function. By using the Fourier transform and defining the jumps of displacements and electric potential components across the crack surface as the unknown functions, two pairs of dual integral equations are derived. To solve the dual integral equations, the jumps of the displacement and electric potential components across the crack surface are expanded in a series of Jacobi polynomials. Numerical examples are provided to show the influences of material properties on the dynamic stress and the electric displacement intensity factors. 展开更多
关键词 functionally graded piezoelectric materials CRACK stress intensity factor stress wave
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Investigation of the effect of military stress on the prevalence of functional bowel disorders 被引量:4
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作者 Xian-Zhao Yu Hai-Feng Liu Zhen-Xue Sun 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第23期3004-3007,共4页
AIM: To investigate the morbidity of functional bowel disorders (FBD) under military stress conditions in order to lay foundations for the prevention and treatment of this disease. METHODS: Four hundred and fifty-seve... AIM: To investigate the morbidity of functional bowel disorders (FBD) under military stress conditions in order to lay foundations for the prevention and treatment of this disease. METHODS: Four hundred and fifty-seven soldiers who were assigned to specified services and 471 soldiers who were assigned to routine services were enrolled using cluster sampling, with the latter as a control group. They were surveyed using the Rome Ⅲ FBD standard questionnaire. The FBD symptom question-naire included FBD-related symptoms, severity, dura- tion or attack time, and accompanying symptoms. RESULTS: The morbidity of the military stress group (14.6%) was significantly higher than in the control group (9.98%) ( 2 = 4.585, P < 0.05). The incidence of smoking, abdominal pain and acid regurgitation ( 2 = 4.761, P < 0.05) as well as the ZUNG anxiety/depression scores ( 2 = 7.982, P < 0.01) were also sig- nificantly higher in the military stress group compared with the control group. ZUNG anxiety ( 2 = 11.523, P < 0.01) and depression ( 2 = 5.149, P < 0.05) scores were higher in the FBD group compared with the non-FBD group. The differences in the ZUNG self-rated anxiety and depression scales between the 2 groups were statistically significant ( 2 = 14.482, P < 0.01 and 2 = 6.176, P < 0.05). CONCLUSION: The morbidity of FBD was higher under military stress conditions. 展开更多
关键词 Military stress functional bowel disorders SOLDIER Self-rating anxiety Depression scale
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SEMI-WEIGHT FUNCTION METHOD ON COMPUTATION OF STRESS INTENSITY FACTORS IN DISSIMILAR MATERIALS 被引量:2
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作者 马开平 柳春图 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第11期1241-1248,共8页
Semi_weight function method is developed to solve the plane problem of two bonded dissimilar materials containing a crack along the bond. From equilibrium equation, stress and strain relationship, conditions of contin... Semi_weight function method is developed to solve the plane problem of two bonded dissimilar materials containing a crack along the bond. From equilibrium equation, stress and strain relationship, conditions of continuity across interface and free crack surface, the stress and displacement fields were obtained. The eigenvalue of these fields is lambda. Semi_weight functions were obtained as virtual displacement and stress fields with eigenvalue?_lambda. Integral expression of fracture parameters, K Ⅰ and K Ⅱ, were obtained from reciprocal work theorem with semi_weight functions and approximate displacement and stress values on any integral path around crack tip. The calculation results of applications show that the semi_weight function method is a simple, convenient and high precision calculation method. 展开更多
关键词 dissimilar material interface crack stress intensity factor semi-weight function method plane fracture problem
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Extended Kantorovich method for local stresses in composite laminates upon polynomial stress functions 被引量:1
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作者 Bin Huang Ji Wang +3 位作者 Jianke Du Yan Guo Tingfeng Ma Lijun Yi 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2016年第5期854-865,共12页
The extended Kantorovich method is employed to study the local stress concentrations at the vicinity of free edges in symmetrically layered composite laminates subjected to uniaxial tensile load upon polynomial stress... The extended Kantorovich method is employed to study the local stress concentrations at the vicinity of free edges in symmetrically layered composite laminates subjected to uniaxial tensile load upon polynomial stress functions. The stress fields are initially assumed by means of the Lekhnitskii stress functions under the plane strain state. Applying the principle of complementary virtual work,the coupled ordinary differential equations are obtained in which the solutions can be obtained by solving a generalized eigenvalue problem. Then an iterative procedure is established to achieve convergent stress distributions. It should be noted that the stress function based extended Kantorovich method can satisfy both the traction-free and free edge stress boundary conditions during the iterative processes. The stress components near the free edges and in the interior regions are calculated and compared with those obtained results by finite element method(FEM). The convergent stresses have good agreements with those results obtained by three dimensional(3D) FEM. For generality, various layup configurations are considered for the numerical analysis. The results show that the proposed polynomial stress function based extended Kantorovich method is accurate and efficient in predicting the local stresses in composite laminates and computationally much more efficient than the 3D FEM. 展开更多
关键词 Kantorovich method Polynomial stress function Composite laminates Local stresses 3D FEM
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Regulation of mitochondrial function and endoplasmic reticulum stress by nitric oxide in pluripotent stem cells 被引量:3
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作者 Estefania Caballano-Infantes José Terron-Bautista +5 位作者 Amparo Beltrán-Povea Gladys M Cahuana Bernat Soria Hajji Nabil Francisco J Bedoya Juan R Tejedo 《World Journal of Stem Cells》 SCIE CAS 2017年第2期26-36,共11页
Mitochondrial dysfunction and endoplasmic reticulum stress(ERS) are global processes that are interrelated and regulated by several stress factors. Nitric oxide(NO) is a multifunctional biomolecule with many varieties... Mitochondrial dysfunction and endoplasmic reticulum stress(ERS) are global processes that are interrelated and regulated by several stress factors. Nitric oxide(NO) is a multifunctional biomolecule with many varieties of physiological and pathological functions, such as the regulation of cytochrome c inhibition and activation of the immune response, ERS and DNA damage; these actions are dose-dependent. It has been reported that in embryonic stem cells, NO has a dual role, controlling differentiation, survival and pluripotency, but the molecular mechanisms by which it modulates these functions are not yet known. Low levels of NO maintain pluripotency and induce mitochondrial biogenesis. It is well established that NO disrupts the mitochondrial respiratory chain and causes changes in mitochondrial Ca^(2+) flux that induce ERS. Thus, at high concentrations, NO becomes a potential differentiation agent due to the relationship between ERS and the unfolded protein response in many differentiated cell lines. Nevertheless, many studies have demonstratedthe need for physiological levels of NO for a proper ERS response. In this review, we stress the importance of the relationships between NO levels, ERS and mitochondrial dysfunction that control stem cell fate as a new approach to possible cell therapy strategies. 展开更多
关键词 Endoplasmic reticulum stress Mitochondrial function Nitric oxide PLURIPOTENCY Cell differentiation Mitochondrial biogenesis
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