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Effects of Maca Extract on Exercise Endurance and Ultrastructure of Mitochondria in Spinal Neurons 被引量:3
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作者 Farong YU Wangjun CHEN +3 位作者 Xiuzhen LIAN Mingren XIE Denglou LI Yunxuan GUO 《Medicinal Plant》 CAS 2018年第3期47-50,共4页
[Objectives] To study the effects of maca extract on the exercise endurance and ultrastructure of mitochondria in spinal neurons.[Methods]First,50 Wistar rats were randomly divided into 5 groups. The control group: no... [Objectives] To study the effects of maca extract on the exercise endurance and ultrastructure of mitochondria in spinal neurons.[Methods]First,50 Wistar rats were randomly divided into 5 groups. The control group: no swimming,administered intragastrically the same volume of distilled water; simple swimming group: free swimming,administered intragastrically the same volume of distilled water; maca extract groups: free swimming,and treated with 4. 0,5. 3,and 8. 0 g/kg dose of maca extracts. Swimming rats swam freely in the circulating water flow of swimming pool and administered for 15 d. On the 16 th d,after the swimming endurance test,the rats were killed painlessly. The ultrastructure of the mitochondria in the spinal neurons was observed with a projection electron microscope,muscle glycogen,malondialdehyde( MDA),superoxide dismutase( SOD),glutathione peroxidase( GSH-Px) and free calcium in muscle were measured by radioimmunoassay.[Results] Compared with the simple swimming group,the swimming time before sinking and total swimming time extended 19. 83%,60. 28%,77. 55% and 55. 34%,73. 91% and 94. 47% respectively,and the differences were statistically significant( P < 0. 01). The sinking times decreased by 34. 35%,51. 18% and 57. 96% respectively,the differences were statistically significant( P < 0. 01). MDA and free calcium decreased by 20. 10%,31. 49% and 38. 72%,respectively with statistically significant differences( P < 0. 01) and 6. 42%,17. 58%and 26. 35% respectively. The levels of SOD,GSH-Px and muscle glycogen increased by 5. 12%,22. 74%,52. 53%,44. 22%,77. 79%and 98. 45% respectively,with statistically significant differences( P < 0. 01) and 35. 08%,47. 83% and 81. 88%,respectively,with statistically significant differences( P < 0. 01). The volume density( Vd),surface density( Sd) and number density( Nd) of mitochondria of spinal neurons decreased by 7. 79%,18. 18%,31. 17%,16. 95%,27. 34%,43. 31% and 13. 51%,23. 19% and 43. 15% respectively.[Conclusions]Maca extract can protect ultrastructure of the mitochondria in the spinal neurons,antioxidant activity,increase muscle glycogen,and improving the exercise capacity. 展开更多
关键词 Maca extract Exercise endurance mitochondria Wistar rats
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Erlotinib combination with a mitochondria-targeted ubiquinone effectively suppresses pancreatic cancer cell survival
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作者 Pui-Yin Leung Wenjing Chen +4 位作者 Anissa N Sari Poojitha Sitaram Pui-Kei Wu Susan Tsai Jong-In Park 《World Journal of Gastroenterology》 SCIE CAS 2024年第7期714-726,共13页
BACKGROUND Pancreatic cancer is a leading cause of cancer-related deaths.Increased activity of the epidermal growth factor receptor(EGFR)is often observed in pancreatic cancer,and the small molecule EGFR inhibitor erl... BACKGROUND Pancreatic cancer is a leading cause of cancer-related deaths.Increased activity of the epidermal growth factor receptor(EGFR)is often observed in pancreatic cancer,and the small molecule EGFR inhibitor erlotinib has been approved for pancreatic cancer therapy by the food and drug administration.Nevertheless,erlotinib alone is ineffective and should be combined with other drugs to improve therapeutic outcomes.We previously showed that certain receptor tyrosine kinase inhibitors can increase mitochondrial membrane potential(Δψm),facilitate tumor cell uptake ofΔψm-sensitive agents,disrupt mitochondrial homeostasis,and subsequently trigger tumor cell death.Erlotinib has not been tested for this effect.AIM To determine whether erlotinib can elevateΔψm and increase tumor cell uptake ofΔψm-sensitive agents,subsequently triggering tumor cell death.METHODSΔψm-sensitive fluorescent dye was used to determine how erlotinib affectsΔψm in pancreatic adenocarcinoma(PDAC)cell lines.The viability of conventional and patient-derived primary PDAC cell lines in 2D-and 3D cultures was measured after treating cells sequentially with erlotinib and mitochondria-targeted ubiquinone(MitoQ),aΔψm-sensitive MitoQ.The synergy between erlotinib and MitoQ was then analyzed using SynergyFinder 2.0.The preclinical efficacy of the twodrug combination was determined using immune-compromised nude mice bearing PDAC cell line xenografts.RESULTS Erlotinib elevatedΔψm in PDAC cells,facilitating tumor cell uptake and mitochondrial enrichment ofΔψm-sensitive agents.MitoQ triggered caspase-dependent apoptosis in PDAC cells in culture if used at high doses,while erlotinib pretreatment potentiated low doses of MitoQ.SynergyFinder suggested that these drugs synergistically induced tumor cell lethality.Consistent with in vitro data,erlotinib and MitoQ combination suppressed human PDAC cell line xenografts in mice more effectively than single treatments of each agent.CONCLUSION Our findings suggest that a combination of erlotinib and MitoQ has the potential to suppress pancreatic tumor cell viability effectively. 展开更多
关键词 Pancreatic cancer ERLOTINIB mitochondria-targeted ubiquinone mitochondria Combination therapy
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Extracellular Vesicles from Mesenchymal Stromal Cells (imEVs) Improve Cold Preservation of Isolated Mitochondria
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作者 Xianpeng Jiang Sergey Rodin +3 位作者 Ken Braesch-Andersen Catherine C. Baucom Karl-Henrik Grinnemo Brent Segal 《Journal of Biosciences and Medicines》 2024年第1期52-63,共12页
Mitochondrial organelle transplantation (MOT) is an innovative strategy for the treatment of mitochondrial dysfunction such as cardiac ischemic reperfusion injuries, Parkinson’s diseases, brain and spinal cord injuri... Mitochondrial organelle transplantation (MOT) is an innovative strategy for the treatment of mitochondrial dysfunction such as cardiac ischemic reperfusion injuries, Parkinson’s diseases, brain and spinal cord injuries, and amyotrophic lateral sclerosis (ALS). However, one of the major challenges for widespread usage is a methodology for preservation of isolated mitochondria. Extracellular vesicles (EVs) are phospholipid bilayer-enclosed vesicles released from cells. EVs carry a cargo of proteins, nucleic acids, lipids, metabolites, and even organelles such as mitochondria. Purpose: To test if EVs enhance the stability of isolated mitochondria. Methods: We mixed isolated mitochondria of fibroblasts with EVs of mesenchymal stromal cells (imEVs) (9:1 in volume) and stored the mixture at 2°C - 6°C for different time periods. We measured morphology, mitochondrial membrane potential (MMP) and mitochondrial ATP content at 0, 2, 5 days. Key findings: After 2 days of storage, the mito-chondria without imEVs lost approximate 70% MMP (RFU: 1822 ± 68), compared to the fresh mitochondria (RFU: 5458 ± 52) (p 0.05). In agreement with MMP, mitochondria without imEVs lost significant mitochondrial ATP content (p 0.05), after 2 days of cold storage, compared to fresh mitochondria. Microscopy showed that imEVs promoted aggregation of isolated mitochondria. Summary: The preliminary data showed that imEVs enhanced the stability of isolated mitochondria in cold storage. 展开更多
关键词 mitochondria Extracellular Vesicles mitochondrial Preservation MOT imEVs
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Verteporfin fluorescence in antineoplastic-treated pancreatic cancer cells found concentrated in mitochondria
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作者 Ying-Qiao Zhang Qing-Hao Liu +3 位作者 Lu Liu Peng-Yu Guo Run-Ze Wang Zhi-Chang Ba 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第3期968-978,共11页
BACKGROUND Traditional treatments for pancreatic cancer(PC)are inadequate.Photodynamic therapy(PDT)is non-invasive,and proven safe to kill cancer cells,including PC.However,the mitochondrial concentration of the photo... BACKGROUND Traditional treatments for pancreatic cancer(PC)are inadequate.Photodynamic therapy(PDT)is non-invasive,and proven safe to kill cancer cells,including PC.However,the mitochondrial concentration of the photosensitizer,such as verteporfin,is key.AIM To investigate the distribution of fluorescence of verteporfin in PC cells treated with antitumor drugs,post-PDT.METHODS Workable survival rates of PC cells(AsPC-1,BxPC-3)were determined with chemotherapy[doxorubicin(DOX)and gemcitabine(GEM)]and non-chemotherapy[sirolimus(SRL)and cetuximab(CTX)]drugs in vitro,with or without verteporfin,as measured via MTT,flow cytometry,and laser confocal microscopy.Reduced cell proliferation was associated with GEM that was more enduring compared with DOX.Confocal laser microscopy allowed observation of GEM-and verteporfin-treated PC cells co-stained with 4’,6-diamidino-2-phenylindole and MitoTracker Green to differentiate living and dead cells and subcellular localization of verteporfin,respectively.RESULTS Cell survival significantly dropped upon exposure to either chemotherapy drug,but not to SRL or CTX.Both cell lines responded similarly to GEM.The intensity of fluorescence was associated with the concentration of verteporfin.Additional experiments using GEM showed that survival rates of the PC cells treated with 10μmol/L verteporfin(but not less)were significantly lower relative to nil verte-porfin.Living and dead stained cells treated with GEM were distinguishable.After GEM treatment,verteporfin was observed primarily in the mitochondria.CONCLUSION Verteporfin was observed in living cells.In GEM-treated human PC cells,verteporfin was particularly prevalent in the mitochondria.This study supports further study of PDT for the treatment of PC after neoadjuvant chemotherapy. 展开更多
关键词 Photodynamic therapy Pancreatic cancer VERTEPORFIN mitochondria CHEMOTHERAPY GEMCITABINE
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Vitamin A regulates mitochondrial biogenesis and function through p38 MAPK‑PGC‑1α signaling pathway and alters the muscle fiber composition of sheep
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作者 Pengkang Song Jiamin Zhao +5 位作者 Fanqinyu Li Xiaoyi Zhao Jinxin Feng Yuan Su Bo Wang Junxing Zhao 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期898-910,共13页
Background Vitamin A(VA)and its metabolite,retinoic acid(RA),are of great interest for their wide range of physiological functions.However,the regulatory contribution of VA to mitochondrial and muscle fiber compositio... Background Vitamin A(VA)and its metabolite,retinoic acid(RA),are of great interest for their wide range of physiological functions.However,the regulatory contribution of VA to mitochondrial and muscle fiber composition in sheep has not been reported.Method Lambs were injected with 0(control)or 7,500 IU VA palmitate into the biceps femoris muscle on d 2 after birth.At the age of 3 and 32 weeks,longissimus dorsi(LD)muscle samples were obtained to explore the effect of VA on myofiber type composition.In vitro,we investigated the effects of RA on myofiber type composition and intrinsic mechanisms.Results The proportion of type I myofiber was greatly increased in VA-treated sheep in LD muscle at harvest.VA greatly promoted mitochondrial biogenesis and function in LD muscle of sheep.Further exploration revealed that VA elevated PGC-1αmRNA and protein contents,and enhanced the level of p38 MAPK phosphorylation in LD muscle of sheep.In addition,the number of type I myofibers with RA treatment was significantly increased,and type IIx myofibers was significantly decreased in primary myoblasts.Consistent with in vivo experiment,RA significantly improved mitochondrial biogenesis and function in primary myoblasts of sheep.We then used si-PGC-1αto inhibit PGC-1αexpression and found that si-PGC-1αsignificantly abrogated RA-induced the formation of type I myofibers,mitochondrial biogenesis,MitoTracker staining intensity,UQCRC1 and ATP5A1 expression,SDH activity,and enhanced the level of type IIx muscle fibers.These data suggested that RA improved mitochondrial biogenesis and function by promoting PGC-1αexpression,and increased type I myofibers.In order to prove that the effect of RA on the level of PGC-1αis caused by p38 MAPK signaling,we inhibited the p38 MAPK signaling using a p38 MAPK inhibitor,which significantly reduced RA-induced PGC-1αand MyHC I levels.Conclusion VA promoted PGC-1αexpression through the p38 MAPK signaling pathway,improved mitochondrial biogenesis,and altered the composition of muscle fiber type. 展开更多
关键词 mitochondria Muscle fiber type PGC-1Α p38 MAPK Retinoic acid Vitamin A
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Mitochondrial dysfunction affects hepatic immune and metabolic remodeling in patients with hepatitis B virus-related acute-onchronic liver failure
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作者 Yu Zhang Xiao-Ling Tian +3 位作者 Jie-Qun Li Dong-Sheng Wu Qiang Li Bin Chen 《World Journal of Gastroenterology》 SCIE CAS 2024年第8期881-900,共20页
BACKGROUND Immune dysregulation and metabolic derangement have been recognized as key factors that contribute to the progression of hepatitis B virus(HBV)-related acute-on-chronic liver failure(ACLF).However,the mecha... BACKGROUND Immune dysregulation and metabolic derangement have been recognized as key factors that contribute to the progression of hepatitis B virus(HBV)-related acute-on-chronic liver failure(ACLF).However,the mechanisms underlying immune and metabolic derangement in patients with advanced HBV-ACLF are unclear.AIM To identify the bioenergetic alterations in the liver of patients with HBV-ACLF causing hepatic immune dysregulation and metabolic disorders.METHODS Liver samples were collected from 16 healthy donors(HDs)and 17 advanced HBV-ACLF patients who were eligible for liver transplantation.The mitochondrial ultrastructure,metabolic characteristics,and immune microenvironment of the liver were assessed.More focus was given to organic acid metabolism as well as the function and subpopulations of macrophages in patients with HBV-ACLF.RESULTS Compared with HDs,there was extensive hepatocyte necrosis,immune cell infiltration,and ductular reaction in patients with ACLF.In patients,the liver suffered severe hypoxia,as evidenced by increased expression of hypoxia-inducible factor-1α.Swollen mitochondria and cristae were observed in the liver of patients.The number,length,width,and area of mitochondria were adaptively increased in hepatocytes.Targeted metabolomics analysis revealed that mitochondrial oxidative phosphorylation decreased,while anaerobic glycolysis was enhanced in patients with HBV-ACLF.These findings suggested that,to a greater extent,hepa-tocytes used the extra-mitochondrial glycolytic pathway as an energy source.Patients with HBV-ACLF had elevated levels of chemokine C-C motif ligand 2 in the liver homogenate,which stimulates peripheral monocyte infiltration into the liver.Characterization and functional analysis of macrophage subsets revealed that patients with ACLF had a high abundance of CD68^(+)HLA-DR^(+)macrophages and elevated levels of both interleukin-1βand transforming growth factor-β1 in their livers.The abundance of CD206^(+)CD163^(+)macrophages and expression of interleukin-10 decreased.The correlation analysis revealed that hepatic organic acid metabolites were closely associated with macrophage-derived cytokines/chemokines.CONCLUSION The results indicated that bioenergetic alteration driven by hypoxia and mitochondrial dysfunction affects hepatic immune and metabolic remodeling,leading to advanced HBV-ACLF.These findings highlight a new therapeutic target for improving the treatment of HBV-ACLF. 展开更多
关键词 Acute-on-chronic liver failure Hypoxia-inducible factor-1α mitochondria Metabolic phenotype Immune cells
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Elaidic acid leads to mitochondrial dysfunction via mitochondria-associated membranes triggers disruption of mitochondrial calcium fluxes
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作者 Hui Liu Xuenan Li +4 位作者 Ziyue Wang Lu Li Yucai Li Haiyang Yan Yuan Yuan 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期287-298,共12页
Elaidic acid(EA)stimulation can lead to endoplasmic reticulum stress(ERS),accompanied by a large release of Ca^(2+),and ultimately the activation of NLRP3 inflammasome in Kupffer cells(KCs).Mitochondrial instability o... Elaidic acid(EA)stimulation can lead to endoplasmic reticulum stress(ERS),accompanied by a large release of Ca^(2+),and ultimately the activation of NLRP3 inflammasome in Kupffer cells(KCs).Mitochondrial instability or dysfunction may be the key stimulating factors to activate NLRP3 inflammasome,and sustained Ca^(2+)transfer can result in mitochondrial dysfunction.We focused on KCs to explore the damage to mitochondria by EA.After EA stimulation,cells produced an oxidative stress(OS)response with a significant increase in ROS release.Immunoprecipitation experiments and the addition of inhibitors revealed that the increase in the level of intracellular Ca^(2+)led to Ca^(2+)accumulation in the mitochondrial matrix via mitochondria-associated membranes(MAMs).This was accompanied by a significant release of m ROS,loss of MMP and ATP,and a significant increase in mitochondrial permeability transition pore opening,ultimately leading to mitochondrial instability.These findings confirmed the mechanism that EA induced mitochondrial Ca^(2+)imbalance in KCs via MAM,ultimately leading to mitochondrial dysfunction.Meanwhile,EA induced OS and the decrease of MMP and ATP in rat liver,and significant lesions were found in liver mitochondria.Swelling of the inner mitochondrial cristae and mitochondrial vacuolization occurred,with a marked increase in lipid droplets. 展开更多
关键词 Elaidic acid(EA) mitochondria-associated membranes(MAMs) Calcium Endoplasmic reticulum mitochondria dysfunction
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Mitochondrial dysfunction in type 2 diabetes:A neglected path to skeletal muscle atrophy
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作者 Jian-Jun Wu Hui-Min Xian +1 位作者 Da-Wei Yang Fan Yang 《World Journal of Orthopedics》 2024年第2期101-104,共4页
Over the course of several decades,robust research has firmly established the significance of mitochondrial pathology as a central contributor to the onset of skeletal muscle atrophy in individuals with diabetes.Howev... Over the course of several decades,robust research has firmly established the significance of mitochondrial pathology as a central contributor to the onset of skeletal muscle atrophy in individuals with diabetes.However,the specific intricacies governing this process remain elusive.Extensive evidence highlights that individuals with diabetes regularly confront the severe consequences of skeletal muscle degradation.Deciphering the sophisticated mechanisms at the core of this pathology requires a thorough and meticulous exploration into the nuanced factors intricately associated with mitochondrial dysfunction. 展开更多
关键词 Mfn-2 Oxidative stress mitochondria metabolism Skeletal muscle atrophy DIABETES
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Pediatric non-alcoholic steatohepatitis:The first report on the ultrastructure of hepatocyte mitochondria 被引量:3
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作者 Joanna M Lotowska Maria E Sobaniec-Lotowska +1 位作者 Sylwia B Bockowska Dariusz M Lebensztejn 《World Journal of Gastroenterology》 SCIE CAS 2014年第15期4335-4340,共6页
AIM:To investigate the ultrastructure of abnormal hepatocyte mitochondria,including their cellular and hepatic zonal distribution,in bioptates in pediatric nonalcoholic steatohepatitis(NASH).METHODS:Ultrastructural in... AIM:To investigate the ultrastructure of abnormal hepatocyte mitochondria,including their cellular and hepatic zonal distribution,in bioptates in pediatric nonalcoholic steatohepatitis(NASH).METHODS:Ultrastructural investigations were conducted on biopsy liver specimens obtained from 10children(6 boys and 4 girls)aged 2-14 years with previously clinicopathologically diagnosed NASH.The disease was diagnosed if liver biopsy revealed steatosis,inflammation,ballooned hepatocytes,Mallory hyaline,or focal necrosis,varying degrees of fibrosis in the absence of clinical,serological,or histological findings of infectious liver diseases,autoimmune hepatitis,metabolic liver diseases,or celiac disease.For ultrastructural analysis,fresh small liver blocks(1 mm3 volume)were fixed in a solution containing 2%paraformaldehyde and 2.5%glutaraldehyde in 0.1 mol/L cacodylate buffer.The specimens were postfixed in osmium tetroxide,subsequently dehydrated through a graded series of ethanols and propylene oxide,and embedded in Epon812.The material was sectioned on a Reichert ultramicrotome to obtain semithin sections,which were stained with methylene blue in sodium borate.Ultrathin sections were contrasted with uranyl acetate and lead citrate,and examined using an Opton EM 900 transmission electron microscope.RESULTS:Ultrastructural analysis of bioptates obtained from children with non-alcoholic steatohepatitis revealed characteristic repetitive mitochondrial abnormalities within hepatocytes;mainly mitochondrial polymorphisms such as megamitochondria,loss of mitochondrial cristae,and the presence of linear crystalline inclusions within the mitochondrial matrix of an increased electron density.The crystalline inclusions were particularly evident within megamitochondria(MMC),which seemed to be distributed randomly both within the hepatic parenchymal cell and the zones of hepatic lobule,without special variations in abundance.The inclusions appeared as bundles viewed longitudinally,or as an evenly spaced matrix in cross section,and frequently caused mitochondrial deformation.The average diameter of these linear structures was 10 nm and the average space between them 20 nm.Sometimes enlarged intramitochondrial granules were seen in their vicinity.Foamy cytoplasm of hepatocytes was found,resulting from the proliferation of smooth endoplasmic reticulum and glycogen accumulation.The perivascular space of Disse was frequently dilated,and contained transitional hepatic stellate cells,as well as mature and/or newly forming collagen fiber bundles.CONCLUSION:Marked ultrastructural abnormalities observed in hepatocyte mitochondria,especially their polymorphism in the form of MMC and loss of mitochondrial cristae,accompanied by foamy cytoplasm,clearly indicate a major role of these organelles in the morphogenesis of pediatric NASH.Our findings seem to prove the high effectiveness of electron microscopy in the diagnosis of the disease. 展开更多
关键词 PEDIATRIC non-alcoholic STEATOHEPATITIS HEPATOCYTE
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Vitamin E supplementation may negatively affect preimplantation development and mitochondrial ultrastructure of vitrified murine embryos
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作者 Mimi-Sophia Sarbandi Nor-Ashikin Mohamed Noor Khan +4 位作者 Nor-Shahida Abdul Rahman Zolkapli Eshak Fathiah Abdullah Mastura Abd Malek Aqila-Akmal Mohammad Kamal 《Asian pacific Journal of Reproduction》 2021年第3期137-144,共8页
Objective:To observe the effects of vitamin E on post-vitrification preimplantation development,gross morphology as well as mitochondrial distribution and ultrastructure.Methods:Twenty-four female C57BL/6NTac mice,age... Objective:To observe the effects of vitamin E on post-vitrification preimplantation development,gross morphology as well as mitochondrial distribution and ultrastructure.Methods:Twenty-four female C57BL/6NTac mice,aged 12-16 weeks,were randomly divided into four groups.Group A did not receive any treatment and served as the control group.Group B was treated with corn oil stripped of tocopherols and served as the vehicle group.Group C was treated with 60 mg/kg body weight of tocotrienol-rich-fraction with corn oil stripped of tocopherols.Group D was treated with 60 mg/kg body weight of alpha-tocopherol with corn oil stripped of tocopherols.All treatments were administered orally for 7 consecutive days.After superovulation and mating with fertile males,2-cell stage embryos were harvested for vitrification.Post vitrification development in vitro,gross morphology and ultrastructure were compared between groups.Results:The number of 2 and 8-cell embryo,and blastocysts in the treatment and control groups were not significantly different(P>0.05).Following vitrification,all 2-cell embryos had equal-sized blastomeres and intact zona pellucida.Mitochondrial aggregation toward the perinuclear region was seen in all of the treatment groups.Both groups C and D had vacuolated mitochondria,which was reflected in the trend of preimplantation development reduction.Conclusions:Vitamin E supplementation of 60 mg/kg body weight does not improve the viability of healthy embryos according to this study.As a result,the most effective dose of vitamin E supplementation may be determined by the initial quality of the embryos. 展开更多
关键词 mitochondria PREIMPLANTATION EMBRYO VITRIFICATION Vitamin E Alpha-tocopherol Tocotrienol-richfraction Transmission electron microscopy
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Effects of tachyplesin on the morphology and ultrastructure of human gastric carcinoma cell line BGC-823 被引量:19
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作者 Li QF Ou Yang GL +1 位作者 Li CY Hong SG 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第5期676-680,共5页
AIM To investigate the morphological andultrastructural changes in the human gastriccarcinoma cell line BGC-823 after being treatedwith tachyplesin.METHODS Tachyplesin was isolated from acidextracts of Chinese horsesh... AIM To investigate the morphological andultrastructural changes in the human gastriccarcinoma cell line BGC-823 after being treatedwith tachyplesin.METHODS Tachyplesin was isolated from acidextracts of Chinese horseshoe crab(Tachypleustridentatus)hemocytes.BGC-823 cells and thecells treated with 2.0mg/L tachyplesin wereexamined respectively under light microscope,scanning and transmission electron microscope.RESULTS BGC-823 cells had undergone therestorational alteration in morphology andultrastructure after tachyplesin treatment.Thechanges were as follows:the shape of cells wasunanimous,the volume enlarged and cellsturned to be flat and spread,the nucleo-cytoplasmic ratio lessened and nuclear shapebecame rather regular,the number of nucleolusreduced and its volume lessened,heter-chromatin decreased while euchromatinincreased in nucleus.In the cytoplasm,mitochondria grew in number with consistentstructure relatively,Golgi complex turned to betypical and well-developed,rough endoplasmicreticulum increased and polyribosomedecreased.The microvilli at cellular surfacewere rare and the filopodia reduced whilelamellipodia increased at the cell edge.CONCLUSION Tachyplesin could alter themalignant morphological and ultrastructuralcharacteristics of human gastric carcinoma cellseffectively and have a certain inducing differen-tiation effect on human gastric carcinoma cells. 展开更多
关键词 STOMACH neoplasms/ultrastructure HORSESHOE crabs STOMACH NEOPLASMS TACHYPLESIN microscopy electron cell MORPHOLOGY
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Effects of potassium deficiency on photosynthesis,chloroplast ultrastructure,ROS,and antioxidant activities in maize(Zea mays L.) 被引量:6
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作者 DU Qi ZHAO Xin-hua +5 位作者 XIA Le JIANG Chun-ji WANG Xiao-guang HAN Yi WANG Jing YU Hai-qiu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第2期395-406,共12页
Potassium(K)deficiency significantly decreases photosynthesis due to leaf chlorosis induced by accumulation of reactive oxygen species(ROS).But,the physiological mechanism for adjusting antioxidative defense system to... Potassium(K)deficiency significantly decreases photosynthesis due to leaf chlorosis induced by accumulation of reactive oxygen species(ROS).But,the physiological mechanism for adjusting antioxidative defense system to protect leaf function in maize(Zea mays L.)is unknown.In the present study,four maize inbred lines(K-tolerant,90-21-3 and 099;K-sensitive,D937 and 835)were used to analyze leaf photosynthesis,anatomical structure,chloroplast ultrastructure,ROS,and antioxidant activities.The results showed that the chlorophyll content,net photosynthetic rate(P_n),stomatal conductance(G_s),photochemical quenching(q_P),and electron transport rate of PSII(ETR)in 90-21-3 and 099 were higher than those in D937 and 835 under K deficiency treatment.Parameters of leaf anatomical structure in D937 that were significantly changed under K deficiency treatment include smaller thickness of leaf,lower epidermis cells,and vascular bundle area,whereas the vascular bundle area,xylem vessel number,and area in 90-21-3 were significantly larger or higher.D937 also had seriously damaged chloroplasts and PSII reaction centers along with increased superoxide anion(O_2^-·)and hydrogen peroxide(H_2O_2).Activities of antioxidants,like superoxide dismutase(SOD),catalase(CAT),and ascorbate peroxidase(APX),were significantly stimulated in 90-21-3 resulting in lower levels of O_2^-·and H_2O_2.These results indicated that the K-tolerant maize promoted antioxidant enzyme activities to maintain ROS homeostasis and suffered less oxidative damage on the photosynthetic apparatus,thereby maintaining regular photosynthesis under K deficiency stress. 展开更多
关键词 potassium deficiency MAIZE PHOTOSYNTHESIS CHLOROPLAST ultrastructure ROS and ANTIOXIDANT
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Taxonomy and ultrastructure of five species of Tetraselmis (Prasinophyceae) isolated from China seas 被引量:3
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作者 Zhang Chengwu Hu Hongjun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2002年第4期557-579,共23页
Comparative ultrastructural investigations on twenty-three isolates of Tetraselmis from the South China Sea, East China Sea and Huanghai Sea, have revealed that these isolates belong to:(1)Tetraselmis chui Butcher; (2... Comparative ultrastructural investigations on twenty-three isolates of Tetraselmis from the South China Sea, East China Sea and Huanghai Sea, have revealed that these isolates belong to:(1)Tetraselmis chui Butcher; (2)T. cordiformis (H. J. Carter) Stein; (3)T. helgolandica Kylin; (4)T. suecica (Kylin) Butcher; (5)T. guangdongensis sp. nov. Except T. helgolandica, the others are new records in China. T. guangdongensis sp. nov. is a new species. Its external and anatomical features closely resemble those of T. impellucida McLachlan et Parke. As in that species the pyrenoid is penetrated from many directions by cytoplasmic channels delimited by a double membrane. The protoplast withdraws from the apical portion of the theca, that portion which overlaid the trough inverts and pops out in the form of a teat. But unlike that species a starch sheath is present; pyrenoid matrix is surrounded by thylakoids which intervenes between the matrix and the starch sheath surrounding pyrenoid; the theca is stratified. 展开更多
关键词 Taxonomy ultrastructure Tetraselmis pyrenoid
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Effects of different LEDs light spectrum on the growth,leaf anatomy,and chloroplast ultrastructure of potato plantlets in vitro and minituber production after transplanting in the greenhouse 被引量:4
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作者 CHEN Li-li ZHANG Kai +5 位作者 GONG Xiao-chen WANG Hao-ying GAO You-hui WANG Xi-quan ZENG Zhao-hai HU Yue-gao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第1期108-119,共12页
Light spectrum plays an important role in regulating the growth and development of in vitro cultured potato(Solanum tuberosum L.) plantlets. The status of potato plantlets at the end of in vitro stage influences the m... Light spectrum plays an important role in regulating the growth and development of in vitro cultured potato(Solanum tuberosum L.) plantlets. The status of potato plantlets at the end of in vitro stage influences the minituber production after transplanting. With 100 μmol m^-2s^-1 total photosynthetic photon flux density(PPFD), a light spectrum study of 100% red light emitting diodes(LEDs) light spectrum(RR), 100% blue LEDs light spectrum(BB), 65% red+35% blue LEDs light spectrum(RB), and 45% red+35% blue+20% green LEDs light spectrum(RBG) providing illumination at the in vitro cultured stage of potato plantlets for 4 weeks using fluorescent lamp as control(CK) was performed to investigate the effects of LEDs light spectrum on the growth, leaf anatomy, and chloroplast ultrastructure of potato plantlets in vitro as well as the minituber yield after 2 months transplanting in the greenhouse. Compared to CK, RB and RBG promoted the growth of potato plantlets in vitro with increased stem diameter, plantlet fresh weight, plantlet dry weight, and health index. Furthermore, BB induced the greatest stem diameter as well as the highest health index in potato plantlets in vitro. Root activity, soluble protein, and free amino acid were also significantly enhanced by BB, whereas carbohydrates were improved by RR. In addition, thickness of leaf, palisade parenchyma and spongy parenchyma was significantly increased by BB and RBG. Chloroplasts under BB and RBG showed well-developed grana thylakoid and stroma thylakoid. Unexpectedly, distinct upper epidermis with greatest thickness was induced and palisade parenchyma and spongy parenchyma were arranged neatly in RR. After transplanting in the greenhouse for 2 months, potato plantlets in vitro from BB, RB, and RBG produced high percentage of large size tuber. BB improved fresh and dry weights of the biggest tuber but decreased tuber number per plantlet. In addition, RBG increased tuber number as well as tuber fresh and dry weight slightly. Our results suggested monochromatic blue LEDs as well as combined red, blue or/and green LEDs light spectrum were superior to fluorescent lamp spectrum in micro-propagation of potato plantlets. Therefore, the application of RBG was suitable;BB and RB could be used as alternatives. 展开更多
关键词 potato plantlets in vitro LEDs light spectrum leaf anatomy chloroplast ultrastructure minituber production
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Study on the Ultrastructures of Antennal Sensilla in Helicoverpa armigera 被引量:2
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作者 WANG Gui-rong, GUO Yu-yuan and WU Kong-ming( State Key Laboratory of Plant Disease and Insect Pests, The Institute of Plant Protection , Chinese Academy of Agricultural Sciences, Beijing 100094 , P. R . China ) 《Agricultural Sciences in China》 CAS CSCD 2002年第8期896-899,共7页
The morphology and structures of antennal sensilla of Helicoverpa armigera are observed under scanning and transmission electron microscopes. Antennae of Helicoverpa armigera are made up of scapus,pedicel and flagellu... The morphology and structures of antennal sensilla of Helicoverpa armigera are observed under scanning and transmission electron microscopes. Antennae of Helicoverpa armigera are made up of scapus,pedicel and flagellum that the latter consists of 70 - 82 segments. The inner side surface of antenna is cataphracted and most of the antennal sensilla lie on its outer, upper and lower surfaces. Both the antennae of male and female contain five kinds of antennal sensilla, namely, sensillum trichodeum, sensillum basiconicum, sensillum chaeticum, ear-shaped sensillum and sensillum coeloconicum, and the kinds, number and distribution of antennal sensilla of both sexes are similar. There are a large number of serrate cuticular processes on antennal surface, especially on the middle and basic parts of antenna. Sensillum trichodeum and sensillum basiconicum, the main chemical odor receptors on antennae of Helicoverpa armigera, consist of cuticularwall, sheath cells, lymph and dendrites. There are significant differences between the internal structures of the two kinds of sensilla. In sensillum trichodeum, the cuticular-wall is thicker, less lipophilic pore channels and has one or a few dendrites, while in sensillum basiconicum, the cuticular-wall is thinner, abundant lipophilic pore channels and has much more dendrites. 展开更多
关键词 HELICOVERPA armigera Antennal sensillum ultrastructures SCANNING ELECTRON microscope Transmission ELECTRON MICROSCOPE
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Influence of compound aescine gel on ultrastructure of vein infused mannitol and its mechanism 被引量:4
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作者 Jinhua Zhang Hefang Wang +2 位作者 Yanling Gui Wei Li Wei Zhou 《Forensic Medicine and Anatomy Research》 2013年第2期30-35,共6页
Purpose: When hypertonic solution 20% mannitol solution was injected into vein, inflammatory mediators and Mitogen-activated protein kinases activated by mannitol can directly induce the fading of vascular endothelial... Purpose: When hypertonic solution 20% mannitol solution was injected into vein, inflammatory mediators and Mitogen-activated protein kinases activated by mannitol can directly induce the fading of vascular endothelial cell, which leads to phlebitis. The study aims to observe the influences of reparil-gel N coated at the proximal parts of the puncture point and basing on this along with infusing heated mannitol to veins to the injure and ultrastructure of veins which were infused the 20% mannitol solution by indwelling needle in vein. Methodology: There are 15 adult New Zealand rabbits. We randomly divided 24 ear veins of 12 adult New Zealand rabbits into Control group, Gelatum group, Gel heated group and injected 20% mannitol solution by vein detained needle in three groups. In Gelatum group, we coated the proximal end of the puncture point with a thin layer of compound aescine gel. Based on Gelatum group, we heated 20% mannitol solution to 35oC-37oC in Gel heated group. Then we observed the intravenous parts and took the veins of each group out to observe their morphology and ultrastructural after the second day of transfusion. 6 ear veins of the rest 3 rabbits as Health group weren’t given any interventions, the veins were taken out to observe their morphology. Results: Comparison between Gelatum group and Gelatum heated group on vascular dilatation, Infiltration of inflammatory cell and Formation of thrombus had no significance, P> 0.05, while the case was different for the comparison on injury of vascular wall, perivascular edema and perivascular hemorrhage, P< 0.05). The statistical significance exists between control group and Gelatum group and Gel heated group, P< 0.05. It was observed under the electron microscope that, in control group, the membrane of endothelial cell peeled off and the mitochondria swelled and vacuolized. In Gelatum group, the membrane of endothelial cell was defective, the parts of the mitochondria were fuzzy, intercellular substance was slightly edematous. In Gel heated group, the mitochondria were clear and intercellular substance slightly swelled. It could be found that the function of phagocyte was complete. Conclusions: Compound aescine gel can prevent phlebitis or reduce the incidence of phlebitis. The combined intervention of coating with a thin layer of compound aescine gel and heating mannitol solution can produce better effect. 展开更多
关键词 Hyperosmotic Solution COMPOUND Aescine GEL PHLEBITIS VEIN Detained Needle ultrastructure
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Toxic effects of meothrin on the gill ultrastructure in grass carp,Ctenopharyngodon idellus 被引量:1
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作者 Zhou Bingsheng Zhang Yongyuan Xu Ying( State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology. Chinese Academy of Sciences, Wuhan 410072. China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1994年第1期52-61,共10页
Toxiceffectsofmeothrinonthegillultrastructureingrasacarp,CtenopharyngodonidellusZhouBingsheng;ZhangYongyuan;... Toxiceffectsofmeothrinonthegillultrastructureingrasacarp,CtenopharyngodonidellusZhouBingsheng;ZhangYongyuan;XuYing(StateKeyLa... 展开更多
关键词 meothrin Ctenopharyngonodon IDELLUS GILL ultrastructure.
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STUDY ON ULTRASTRUCTURE IN SEVERAL TYPICAL HALOPHYTES 被引量:1
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作者 Zhao Manrong Jia Huixian Gansu Agricultural University, Lanzhou, 730070 《干旱区资源与环境》 CSCD 1993年第Z1期338-341,337,共5页
The characteristics of form and the structure of typical salt plants are usually consid-ered as suitable to the condition of salinity. So after studying their microstructure, we alsodid more careful observation of the... The characteristics of form and the structure of typical salt plants are usually consid-ered as suitable to the condition of salinity. So after studying their microstructure, we alsodid more careful observation of their ultrastructure and found some characteristics. Thesecharacteristics can not only explain the way in which they have adapted to salinization 展开更多
关键词 Salt Plants ultrastructure CHLOROPLAST Proteoplast Self-Phagosome
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THE ULTRASTRUCTURE OF TOXOPLASMA GONDII TACHYZOITES AND THE EFFECT OF USNIC ACID ON IT 被引量:1
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作者 吴杰 杨少毅 程彦斌 《Journal of Pharmaceutical Analysis》 CAS 1996年第1期91-94,共4页
THEULTRASTRUCTUREOFTOXOPLASMAGONDIITACHYZOITESANDTHEEFFECTOFUSNICACIDONIT(吴杰)(杨少毅)(程彦斌)WuJie;YangShaoyi;Chen... THEULTRASTRUCTUREOFTOXOPLASMAGONDIITACHYZOITESANDTHEEFFECTOFUSNICACIDONIT(吴杰)(杨少毅)(程彦斌)WuJie;YangShaoyi;ChengYanbin;(Dept.ofp... 展开更多
关键词 TOXOPLASMA GONDII tachyzoite ultrastructure usnic ACID
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Influence of Gossypol on Ultrastructure and mRNA Expression of Bax and Bcl-2 in Mice Testis 被引量:1
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作者 Zhao Shu-chen Yuan Yan-bo +1 位作者 Hou Zhen-zhong Liu Ke-xiang 《Journal of Northeast Agricultural University(English Edition)》 CAS 2017年第3期75-83,共9页
The objective was to evaluate the toxicity effect of gossypol on ultrastructure of mouse testis and the expression of Bax mRNA and Bcl-2 mRNA of sperm cells in mice.Forty-eight male mice were randomly divided into fou... The objective was to evaluate the toxicity effect of gossypol on ultrastructure of mouse testis and the expression of Bax mRNA and Bcl-2 mRNA of sperm cells in mice.Forty-eight male mice were randomly divided into four groups:control group,L-group(30 mg·kg^(-1)·d),M-group(60 mg·kg^(-1)·d)and H-group(120 mg·kg^(-1)·d)and were orally administrated with gossypol diluted by sodium carboxymethyl cellulose(SCC)or SCC(control group)for 20 days.On the 21st day,all the mice were killed and ultrastructure changes of testis were observed by TEM.mRNA expression of Bax and Bcl-2 in testis was measured by semiquantitative RT-PCR.The results showed that the testicular ultrastructure in three treated groups was gradually damaged,according to the dosage of gossypol and cellular structure disordered and organelle degenerated,manifesting vacuolation of mitochondria,expansion of endoplasmic reticulum.mRNA expression of Bcl-2 in testis significantly increased(p<0.05)in L-group and then significantly decreased(p<0.05,p<0.01)in M-group and H-group compared with that in the control group;mRNA expression of Bcl-2 in M-group and H-group significantly decreased(p<0.05,p<0.01)than that in L-group and Bcl-2 mRNA expression in H-group showed a significant decrease(p<0.05)compared with that in M-group.On the other hand,mRNA expression of Bax significant increased(p<0.05,p<0.01)in M-group and H-group than that in the control group.The ratio of Bcl-2/Bax significantly reduced(p<0.05,p<0.01)in the treated group than that in the control group and was found to be an obvious dose-dependent.It demonstrated that the gossypol could induce the changes on ultrastructure of mice testis,down-regulate mRNA expression of Bcl-2 and up-regulate mRNA expression of Bax,which indicated that sperm cells were induced apoptosis. 展开更多
关键词 GOSSYPOL Bcl-2 mRNA Bax mRNA ultrastructure TESTIS mice
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