Effect of intraoperative blood salvage on erythrocyte morphosis observed under atomic force microscope

AIM: To investigate the effect of intraoperative blood salvage (IOBS) on the morphosis of erythrocytes with atomic force microscopic (AFM) observation. METHODS: Blood samples from the patients with spinal operation were collected before operation (T1) and 1 h after IOBS (T4). Unprocessed blood (T2) and processed blood (T3) in the cell saver were also measured. An AFM with nanometer resolution was used to examine the ultrastructure of membrane surface of the erythrocytes in the samples. RESULTS: The percentage of heteromorphous erythrocytes in T1 samples was the lowest. There were significant differences in AFM images and height profile of a single erythrocyte between salvaged blood and venous blood. AFM images at 1 μm range showed that the distribution of the particles on the erythrocyte membrane surface in unprocessed blood in cell saver was significantly different from the other blood samples. CONCLUSION: There are significant changes in the AFM images of erythrocytes and the ultrastructure of the membrane surface in salvaged blood.     

Effect of cardiopulmonary bypass for 30 min on structure and mechanical properties of erythrocyte membrane surface

AIM: To observe and analyze the effect of cardiopulmonary bypass(CPB) for 30 min on surface ultra-structure and mechanical properties of the erythrocyte membrane by atomic force microscopy(AFM).METHODS: Ten cases of elective patients in cardiac surgery were selected in the study and divided into control(CON) group and CPB group. The central venous blood(2 mL) before surgery and 30 min after CPB was collected with heparin anticoagulation. The non-circular red blood cells were counted under a stand fluorescence microscope. AFM was used to examine the ultrastructure of the membrane surface and measure the force curve of the erythrocytes.RESULTS: The percentage of non-circular red blood cells in CPB group showed no statistically significant differences as compared with CON group. AFM images showed that the significant differences of membrane surface concave and convex, evenness, particle distribution, the surface average roughness(Ra), the surface root mean square roughness(Rq) and cell membrane adhesion between CPB group and CON group were observed. However, the membrane deformation resilience and curve slope had no significant difference between the 2 groups.CONCLUSION: Cardiopulmonary bypass for 30 min changes the morphology and ultrastructure of the erythrocyte membrane surface, and increases the adhesion between cells.     

Effects of artesunate on membrane surface morphology of human gastric cancer SGC-7901 cells observed under atomic force microscope

AIM: To detect the membrane surface morphology of cancer cells treated with artesunate (ART) under atomic force microscope (AFM). METHODS: Human gastric cancer SGC-7901 cells were cultured and treated with different concentrations of ART for 24 h. The membrane surface morphology, three-dimensional structures and ultrastructural changes of SGC-7901 cells were observed under AFM. The apoptosis of SGC-7901 cells was detected by flow cytometry. RESULTS: The AFM images revealed that the cell nuclear area was full and the surface of cell membrane was flat and smooth in control group. Compared with control group, the cell nuclear area collapsed and suffered atrophy, and the membrane surface had more pores in ART treatment groups. More pores were observed and the diameter of the pores was increased with the increase in ART concentration. The cell membrane ultrastructure showed that the particles in control group had an intensive distribution, some were cord-shaped and some gathered into a mass. The particles in ART treatment groups were fewer and distributed sparsely. Moreover, there were obvious lacunae in the surface of cell membrane. Quantitive measurement found that the height of cell nucleus area was decreased, and the surface root mean square roughness (Rq) and the surface average roughness (Ra) became smaller in ART treatment groups compared with control group. The apoptotic rates of the cells in ART treatment groups were increased with the increase in ART concentration, and were all significantly higher than that in control group. CONCLUSION: Our findings emphasize the significance of AFM in exploring the changes of the membrane surface morphology at nano-scale resolution following the treatment with anticancer drugs, which could not only identify the specific characteristics of morphological changes of the tumor cells, but also provide micromorphological references to reveal the mechanisms of anticancer drugs.     

Emodin inhibits proliferation and blocks cell cycle of human breast cancer MCF-7 cells

AIM：To investigate the effects of emodin on the proliferation of human breast cancer MCF-7 cells and its mechanisms. METHODS：MTT assay was used to observe the viability of MCF-7 cells. The cell cycle distribution and apoptosis of MCF-7 cells was analyzed by flow cytometry. The membrane surface morphology and three-dimensional ultrastructure of MCF-7 cells were observed under atomic force microscope (AFM). RESULTS：MTT assay showed that emodin could inhibit MCF-7 cell proliferation in a dose-dependent manner. Flow cytometric analysis demonstrated that emodin induced cell cycle arrest at G0/G1 phase. Annexin V/PI double staining confirmed that emodin had no effect on cell apoptosis. AFM images revealed that the cell nuclear area was full and the surface of cell membrane was flat and smooth in control group. Compared with control group, the cell nuclear area collapsed and shrank in emodin group at 48 h. The cell membrane ultrastructure showed that the particles in emo-din group had an intensive distribution. The height of cell nuclear area was decreased, and the surface average roughness (Ra) and root mean square roughness (Rq) were elevated in emo-din group compared with control group. CONCLUSION: Emodin has cytotoxicity on MCF-7 cells via cell cycle arrest at G0/G1 phase and ultrastructural changes.     

Observation of molecular interaction between gold nanoparticle and VEGF165 with atomic force microscope

AIM: To investigate the molecular interaction between gold nanoparticles (GNP) and vascular endothelial growth factor 165(VEGF₁₆₅) under atomic force microscope (AFM). METHODS: Before and after incubation with VEGF₁₆₅, GNP were screened by integrated tools including AFM, ultraviolet-visible absorption spectroscopy and particle size analysis under near-physiological condition. In addition, GNP at different concentrations were incubated with VEGF₁₆₅, then added to starved human umbilical vein endothelial cells(HUVECs). The ultrastructural changes of HUVECs surface were examined by AFM. The effects of GNP on the growth of HUVECs were assessed by MTT assay. RESULTS: After treated with VEGF₁₆₅, the GNP absorption peak revealed a slight red shift, and the size distribution of GNP was increased from 20 nm to 30 nm. By AFM imaging, the diameter of GNP was (22.05±1.52) nm in average while the average diameter of GNP-VEGF₁₆₅ was (33.91±2.61) nm. Binding of GNP and VEGF₁₆₅, and the formation of GNP-VEGF₁₆₅ core-shell complex were indicated by the AFM imaging. AFM screening showed the changes of ultrastructure on HUVECs surface. The group of VEGF₁₆₅ displayed the signs of cell proliferation. Granulation of cell surface, increase in cell-to-cell contact, formation of pseudopodia and appearance of membranes pores were all observed. The proliferation of HUVECs was inhibited by GNP with MTT assay. CONCLUSION: GNP bind to VEGF₁₆₅ through chemical bonds to block or inactivate the receptor binding sites of VEGF₁₆₅. Therefore, GNP inhibit VEGF₁₆₅-induced proliferation of HUVECs.     

Ultrastructure and function of human bone marrow mesenchymal stem cells

AIM: To study the cytoskeleton of mesenchymal stem cells (MSCs), the ultrastructure and function relationship by using atomic force microscope (AFM). METHODS: The ultrastructures and morphological feature of MSCs cultured for 1 d and 5 d were studied by AFM. RESULTS: The special structures that possess peculiar morphological characteristic of MSCs such as cytoskeleton, pseudopod, microfilament etc were identified by AFM, and these special structures are difficult to observe under electronic microscopy or other conventional optical microscopy. CONCLUSIONS: AFM is a powerful tool to study ultrastructures, morphological features, and cytoskeleton of stem cells in near physiological conditions. Its application prospect in cellular biology is extensive. The special cytoskeleton and other structures of MSCs observed above may represent the structural base of multi-differentiation potential of MSCs.     

Mixed culture of human iPSCs with rabbit corneal endothelial cells induces differentiation of iPSCs

AIM:To investigate the morphology and protein expression of human induced pluripotent stem cells(iPSCs) in the mixed-culture environment with rabbit corneal endothelial cells(CECs) and to provide the experimental basis and the mechanism of iPSC differentiation into CECs. METHODS:Primary rabbit CECs were isolated with trypsin and subcultured. The human iPSCs were cultured and amplified by a feeder-free method and their characteristics were evaluated by Western blotting. iPSCs labeled with quantum dots of appropriate concentration were used to establish mixed-culture model with rabbit CECs. The morphology of iPSCs was evaluated by atomic force microscopy(AFM) and inverted microscopy. The protein expression of CD31, CD34, CD133 and aquaporin 1(AQP1) in iPSCs was tested by the method of immunofluorescence. RESULTS:The rabbit CECs were hexagonal and showed a typical cobblestone appearance. iPSCs grew in the cloning form, and 3 pluripotent proteins Oct4, Nanog and Sox2 were expressed positively. 1/4 suspension of iPSCs labeled with 10 nmol/L quantum dots and 60% confluence of rabbit CECs made best mixed culture for each other. Under AFM and inverted microscope, the volume of iPSC became bigger and the nuclear-cytoplasm ratio was decreased after 7 days of mixed culture. Some granular protrusions of the membrane were observed and the surface roughness of the cell membrane increased. The protein expression of CD31, CD34, CD133 and AQP1 in iPSCs was negative, while AQP1 was detected after mixed culture for 2 weeks. CONCLUSION:iPSCs morphologically change to endothelial-like cells after mixed culture with rabbit CECs and express the marker protein AQP1 of CECs at the same time.     

Analysis of chromosome aberration due to ethidium bromide using AFM

AIM: To study chromosome aberration due to ethidium bromide (EB),a heterocyclic organic compound and an organic fluorescence dye commonly used in biochemical experiment,and to help further understanding the molecular mechanism of tumor or cancer induced by EB and other heterocyclic organic compounds.METHODS: The toxicity action of EB was evaluated from three aspects including DNA,chromosome and embryo stem cells (ESCs) using atomic force microscopy (AFM),and thereinto,the morphology structural difference of ESCs treated with two EB doses was also valuated.RESULTS: The morphological structures of DNA,chromosome and ESCs were dramatically damaged.The average height of DNA decreased 0.5 nm;chromosomal arms were ruptured from centromere location;molecules of cellular membrane congregated and loop-like structure formed,and ES cell masses were collapsed and became dead after large EB doses treatment and mesh-like morphological structure was discernable.CONCLUSION: The toxicity action of EB is strong and destroys the surface structure of DNA and chromosome.EB induces structural aberration of ES cellular membrane and cell death.The results indicate that the action of EB is externalized at gene level and cell level,which is important to study the carcinogenicity of EB.     

Effects of DSF/Cu on surface ultrastructures and mechanical properties of human breast cancer and normal breast epithelial cells

AIM: To study the effects of disulfiram/copper complex (DSF/Cu) on ultrastructures and mechanical properties of human breast cancer and normal breast epithelial cells by atomic force microscopy (AFM) based on the nanoscale resolution and piconewton force measurement level. METHODS: The change of cell cycle and apoptotic rate of MCF-7 cells and MCF-10A cells induced by DSF/Cu were compared by flow cytometry. The cell surface morphology, ultrastructure, height, width and roughness were detected by AFM. The effects of DSF/Cu on the hardness (Young's modulus) of the 2 kinds of cells were determined by AFM with indentation technique. RESULTS: DSF/Cu significantly induced apoptosis of the MCF-7 cells in a dose-dependent manner, whereas had little effect on the MCF-10A cells. The cell cycle analysis showed that DSF/Cu induced G₂/M arrest in the MCF-7 cells, but led to G₀/G₁ arrest in the MCF-10A cells. The AFM images showed that the MCF-7 cells shrank and showed smaller and smoother morphology, and the filopodia were retracted obviously, even some became into lamellipodia, or disappeared completely after treated with DSF/Cu at concentrations of 400 and 800 nmol/L. The quantitative analysis indicated that the MCF-7 cells showed smaller width and larger height, and the root mean square roughness and average roughness were decreased significantly in a dose-dependent manner after treated with DSF/Cu at concentrations of 400 and 800 nmol/L. However, little effect in the MCF-10A cells was observed. The biomechanics test at a single cell level demonstrated that the Young's modulus of the MCF-7 cells and MCF-10A cells were both increased, yet the proportion increased in the MCF-7 cells was much higher than that in the MCF-10A cells after treated with DSF/Cu at concentrations of 400 and 800 nmol/L. CONCLUSION: DSF/Cu has strong antitumor effect on breast cancer with high efficiency and low toxicity by changing the properties of the biomechanics specifically.     

Inhibitory effects of nm23-H1 gene on proliferation and invasion of A549 cell line

AIM:To study the inhibitory effects of nm23-H1 gene on proliferation and invasion of human lung adenocarcinoma A549 cell line. METHODS:Recombinant eukaryotic expression vector pcDNA3.1-nm23-H1 containing full length of human nm23-H1 cDNA was constructed and transfected into a human lung adenocarcinoma A549 cell line by lipofectamine. Cell strain that expressed nm23-H1 stably was screened out by G418 and named pcDNA-nm23-A549. Expression of nm23-H1 was identified by RT-PCR and immunohistochemistry. Growth curves were drawn to detect the inhibitory effects on cell proliferation. Cell cycle of pcDNA-nm23-A549 was examined by flow cytometry. Atomic force microscopy was used to observe the filopodia on the surface of the cells. RESULTS:Introduction of nm23-H1 obviously inhibited the proliferation of A549. Expression of nm23-H1 did not induce apotosis in A549 cells but increased the percentage of phase G₁ cells and decreased phase S cells. Meanwhile, phase G₁ to phase S transition was restrained. Filopodia in the cell surface was much fewer and its structure changed in cells transformed. CONCLUSION:nm23-H1 is capable of inhibiting A549 proliferation and decreasing its metastatic ability, probably by interfering with cell cycle and cell surface structure.     

Study of experimental varicocele on cell apoptosis of epididymis in adolescent rats

AIM: To study the cell apoptosis and the change of microstructure and ultrastructure in epididymis with experimental varicocele (EVC) in rats. METHODS: Experimental varicocele model was induced by partial ligation of the left renal vein in adolescent Sprague-Dawley Wistar rats. Apoptotic cells were detected by in situ terminal deoxynucleotityl transferase-mediated dTUP nick end labeling (TUNEL) technique. The corpus epididymis of the rats was prepared for light and electron microscopic observation. The microstructure and ultrastructure of the epididymis were studied. RESULTS: There was certain proportion of apoptosis cells in epididymis cells in control rats. The incidence of apoptosis increased remarkably in experimental group than that in control group (P<0.01). Under light microscope, the main changes observed were epididymis’s duct shrinked and the blebbing appeared in the epithelial cells. With electron microscope, numerous large lysosomes, increased residual bodies, expanded the endoplasmic reticulum, clouding the mitochondrion’s spinal, the vacuole in the Golgi complex, and defected main cellular organelles were also observed. Beside nuclear membrane, nuclear chromatin dense, lump, the microvilli of the columnar epithelial cells were sparse and showed local defects. CONCLUSIONS: The experimental varicocele in adolescent rats lead to an increase in cell apoptosis, microstructure and ultrastructure lesions in the epididymis, which may be another important reason of infertility resulting from varicocele.     

Differentiation of mesenchymal stem cells derived from human umbilical cord

AIM: To explore an ideal method to induce the differen-tiation of human umbilical cord mesenchymal stem cells(hUCMSCs) into neuron-like cells and to provide some evidence for the transplantation of hUCMSCs for spinal cord injury. METHODS: The hUCMSCs were isolated from human umbilical cord digested with collagenase Ⅱ. The hUCMSCs was verified by flow cytometry analysis. The passage 5 cells were randomly divided into 4 groups. The differentiation of hUCMSCs was induced by bFGF in group A, bFGF and BDNF in group B, or BHA, bFGF and BDNF in group C, while the cells in group D served as a control group cultured with DMEM-F12 and 10% FBS. Two weeks later, the expression of nestin, neurofilament protein H(NEFH) and glial fibrillary acidic protein(GFAP) was detected by real-time PCR and immunocytochemistry. The morphological changes of cells were observed under an atomic force microscope. RESULTS: Mesenchymal stem cells were isolated and cultured from human umbilical cord by enzyme digestion. hUCMSCs expressed CD29, CD44 and CD105, but no CD34, CD45 or HLA-DR. After cultured with inducing medium for 2 weeks, the cells were successfully induced into neuron-like cells. The appearance of the cells had great change. The induced hUCMSCs developed round cell bodies with multiple neurite-like extensions observed under an atomic force microscope. The result of real-time PCR showed that nestin was positive in A, B and C groups, and NEFH was positive in A and B groups, but GFAP was negative in 4 groups. The difference of nestin and NEFH expression among the induced groups was significant(P<0.05). CONCLUSION: Mesenchymal stem cells were isolated and cultured from human umbilical cord by enzyme digestion in vitro, and all the hUCMACs presented stable biological properties. Moreover, hUCMSCs were induced to differentiate into neuron-like cells in vitro via bFGF combined with BDNF.     

Effects of nicotine on ultrastructure and cytokine secretion of human periodontal ligamental fibroblasts

［ABSTRACT］AIM: To explore the effects of nicotine on surface morphology, ultrastructure, proliferation, cell cycle and cytokine secretion of human periodontal ligamental fibroblasts (PDLFs). METHODS: Before and after treatment with nicotine, the surface morphology and ultrastructure of PDLFs were observed under atomic force microscope and transmission electron microscope. The cell proliferation was examined by MTT assay. The cell cycle and apoptotic rate were determined by flow cytometry. The levels of basic fibroblast growth factor (bFGF), insulin-like growth factor I (IGF-I), transforming growth factor β1 (TGF-β1), intercellular adhesion molecule 1(ICAM-1), vascular cell adhesion molecule 1 (VCAM-1) and vasculr endothelial growth factor (VEGF) were detected by ELISA. RESULTS: After treatment with nicotine, pycnosis, vacuolation in the cytoplasm, and karyorrhexis were observed in the PDLFs. The rough endoplasmic reticulum expanded and mitochondria swelled. Cell proliferation was inhibited in a time- and dose-dependent manner. The cell number in G0/G1 phase increased while that in G2 phase and S phase decreased. The apoptotic rate and the rate of cycle arrest were increased with the increase in nicotine concentration. After treatment with nicotine, the secretion levels of bFGF and IGF-I declined, while the levels of ICAM-1, VCAM-1, TGF-β1 and VEGF increased. CONCLUSION: Nicotine changes the surface morphology and ultrastructure of PDLFs to apoptosis-like characters and inhibits the proliferation of the cells. Nicotine may affect the repairment of PDLFs by regulating the levels of cytokine secretion.     

Effect of Jinan injection on ultrastructure of lung cancer cell lines

AIM: To investigate the effects of Chinese medicine, Jinan injection, on ultrastructure and mitochondria in cultured lung cancer cell lines. METHODS: The cultured lung cancer cell lines PG and PAa were used and divided into 4 groups: control (C), cisplatin (DDP), Jinan (JA) and Jinan in combination with cisplatin (DJ), respectively. The changes of morphology and mitochondria membrane potential, intracellular Ca²⁺ and pH in every group were observed by inverted microscope and electronic microscope as well as by using flow cytometry, staining by rhodamine, Fluo-3 and BCECF, respectively. RESULTS: Degeneration cells showed chromatin condensation and peripheral congregation. In cytoplasm autophage lysosome increased and myelinoid body was seen easily. In mitochondria structure, where the space between the inner and outer membranes of these organelles expanded as the matrix was compressed. The electron-dense or swelled was observed as vacuole degeneration and its matrix showed electron-lucent. Compared to control, mitochondria membrane potential increased in every group after 24 h and 48 h treatment. DDP increased intracellular calcium ion in PG cells, however, in PAa cells, JA and DJ decreased it. Intracellular pH got lower at 24 h and higher at 48 h in PG and PAa cells. There were significance in every group vs control in PG and PAa by statistic t-test (P＜0.01). CONCLUSION: Apoptosis was induced in PG and PAa cell lines by Jinan injection and DJ. Mitochondria matrix displayed electron-dense, mitochondrial potential, intracellular calcium ion and pH showed an increasing trend. Mitochondria damages may play an important role in apoptosis induced by Jinan and DJ.     

The abnormalities of microenvironment in myelodysplastic syndrome

Myelodysplastic syndrome(MDS)is considered as a preleukemic course, characteristic of hypercel ular marrow and pancytopenia.Many studies have demonstrated that defects occur in the heamtopoietic cels from patients with MDS.Recently, many abnormal changes in apoptosis, proliferation, ability of hematopoietic support, cytokine secret ion, clonal origin of stromal cells and angiogenesis have also been re vealed in the bone marrow microenvironment of MDS patients.     

Effects of hypoxia exposure for different time on structure and function of red blood cells in rats

AIM: To investigate the effects of hypoxia exposure on the structure and function of erythrocytes in rats at different time. METHODS: Male SD rats (n=40) were randomly divided into 5 groups, normal control group, 1-week hypoxia group, 2-week hypoxia group, 3-week hypoxia group and 4-week hypoxia group, with 8 rats per group. The rats in hypoxia groups were placed in the simulated 5 800 m of high altitude in a hypobaric chamber for different time. The values of detected blood, erythrocyte deformation index, erythrocyte osmotic fragility, erythrocyte oxygen dissociation, erythrocyte apoptosis and bone marrow biopsy were determined. RESULTS: Compared with normal control group, the red blood cell count, hemoglobin content, mean corpuscular volume and mean corpuscular hemoglobin significantly increased (P<0.01). Eversion rate of phosphatidylserine of erythrocytes increased. Oxygen half-saturation of hemoglobin increased (P<0.05). Bone marrow erythroid proliferation increased. The erythrocyte deformation index and erythrocyte osmotic fragility decreased significantly (P<0.01). In addition, oxygen dissociation curves shifted to the right. CONCLUSION: In the early stage of hypoxia, compared with normal control group, the changes of erythrocyte structure and function increase the oxygen supply to the tissue and are conducive to adapting to the plateau. However, with the extension of hypoxia, excessive erythrocytosis results in thrombosis, microcirculation disturbance and aggravating tissue hypoxia.     

An oxidative injury model of human kidney epithelial cells

AIM: To establish an injured cell model using human kidney proximal tubule epithelial cell line (HKC) to mimic the oxidative injury by hydrogen peroxide (H₂O₂). METHODS: The cell viability, the content of malondialdehyde (MDA) in the culture supernatant and the activity of intracellular superoxide dismutase (SOD) were detected to investigate the degree of cell injury. Osteopontin (OPN) expressed on the cell membrane surface were observed by laser confocal microscopy before and after cell injury. The changes of cellular morphology and the ultrastructure of membrane surface were observed under scanning electronic microscope. RESULTS: After HKC cells were treated with H₂O₂ at the concentration of 1 mmol/L for different time, the cell viability and the activity of SOD decreased and the content of MDA increased. The expression level of OPN significantly increased and reached to maximae at 1 h. The injured cells appeared shriveled and rough surface, and the shedding of most flagellae was also observed. CONCLUSION: H₂O₂ induces severer injury in HKC cells, including not only the cell viability and membrane surface ultrastructure, but also the OPN expression on the membrane, which could bind calcium oxalate crystal. Therefore, treatment with H₂O₂ at the concentration of 1 mmol/L for 1 h can be used to establish an oxidative injury model in HKC cells.     

Effect of IL-8 on mitochondrial fusion and fission gene expression in human lung adenocarcinoma cell line A549 during cell migration

AIM: To investigate the changes of migration of lung adenocarcinoma cells promoted by IL-8 and the inner and outer mitochondrial membrane dynamic changes during this process.METHODS: Human lung adenocarcinoma cell line A549 was divided into control group and IL-8 group. Cell migration was analyzed by scratch detection and Transwell assay. The secretion of endogenous IL-8 was detected by ELISA. The protein levels of mitochondrial cytochrome C (Cyt C) and mitochondrial outer membrane protein Tom20 was detected by Western blot. The mRNA expression of mitochondrial fusion genes Mfn1, Mfn2 and OPA1 and fission genes Fis1, Drp1 and MTP18 was detected by RT-PCR. The morphological changes of mitochondria were observed by MitoTracker Red CMXRos dye staining and confocal microscopy.RESULTS: The migratory rate of A549 cells and endogenous secretion of IL-8 in A549 cells were higher than those in SPC-A-1 cells. The migratory rate of A549 cells was improved by IL-8 in a time-dependent manner. Compared with control group, the Tom20 protein expression was increased (P<0.05), and the Cyt C protein expression was decreased (P<0.05). The expression of mitochondrial outer membrane fusion genes Mfn1 and Mfn2 was increased (P<0.05), and the expression of mitochondrial inner membrane fusion gene OPA1 was decreased (P<0.05). The expression of fission genes Drp1 and MTP18 were decreased (P<0.05), while the expression of Fis1 was no change (P>0.05). Under confocal microscope, the punctate aggregates in the mitochondria of the A549 cells treated with IL-8 were observed.CONCLUSION: The migratory rate of A549 cells is increased by IL-8, which is related to the changes of mitochondrial fusion genes and the fission genes.     

Proliferation and apoptosis of neuroendocrine cells in ovarian epithelial tumors

AIM: The purpose of this study was to observe the morphological features of neuroendocrine cells (NECs)， their proliferation and apoptosis in ovarian epithelial tumors, and to discuss their biological and clinical significance. METHODS: 79 specimens of ovarian epithelial tumor samples were collected, of them 20 benign, 18 boderline, 41 milignant tumors, and 22 normal ovaries were investigated immunohistochemically. Chromogranin A was used to detect NECs and their proliferation and apoptosis were examined by double-label staining of chromogranin A and Ki67 or TUNEL. RESULTS: The positive rate of CgA, distribution and staining intensity in ovarian epithelial tumors were higher than those in normal ovary. NECs showed various shapes with neuronoid protuberances stretching to the neighboring cells or basement membrane. Occasionally, they might touch together. No TUNEL positive coexpression in all NECs was observed by double-label staining, but some NECs were coexpressed with Ki67. CONCLUSION: NECs of ovarian epithelial tumors like cancer cells showed a proliferation, but no apoptosis. Their secretion might promote their neighboring non-NECs to proliferate and prevent them from apoptosis.     

荔枝、龙眼叶片表皮结构的研究

 用扫描电镜观察了荔枝、龙眼各3个品种的叶表皮。结果表明, 龙眼叶片上表皮角质层平均厚度2.36μm , 显著大于荔枝(1.93μm) 。荔枝、龙眼叶片下表皮具有大量的乳状突; 乳状突的密度, 荔枝为7 855.1个/mm² , 龙眼为7 708.8个/mm² ; 荔枝的乳状突呈近半圆形, 宽9.55μm, 高5.71μm; 龙眼的乳状突为长形, 宽5.94μm, 高10.38μm; 荔枝、龙眼气孔长×宽分别为6.98μm ×3.09μm、7.14μm×2.30μm。荔枝、龙眼表皮结构特征差异明显。