Abstract: Objective To establish a lung metastasis model based on Lewis subcutaneously-implanted tumors in C57BL/6 mice, and observe the pathological and ultrastructural changes in lung metastasis. Methods C57BL/ 6 mice were subcutaneously implanted with Lewis cells in the armpit of the right forelimb. The tumor volume was measured regularly and a survival curve was generated. Anatomical observations were performed on mice whose survival time was more than 35 days, hematoxylin-eosin (HE) staining was used to detect pathological changes in the lung tissue, and the ultrastructure of the lung tissue was observed by transmission electron microscopy. Results The subcutaneous tumor formation rate of the right forelimb axillary was 100% at 14 days after inoculation, and mortality occurred from 22 days, with a mean life span for the mice of (33. 00 ± 6. 98) days. Anatomically, typical metastases were observed on the lung surface, which had a round translucent appearance and surrounding hemorrhage. HE showed intense staining of the lung metastases, which were nearly round in appearance, with obvious boundaries with the surrounding tissue. The tumor cells were closely arranged and contained abundant capillaries. Under transmission electron microscopy, the tumor cells in the lung metastases showed significant atypia, including meganucleus, dicaryon, and singular nuclei. The cytoplasm of the cells contained a large number of glycogen particles and mitochondria, and cell junctions were evident between tumor cells. Conclusions Prolongation of the survival time resulted in the formation of typical lung metastases in mice with a subcutaneous tumor. The pathological and ultrastructural changes in lung metastases were consistent with the characteristics of malignant tumors.

Abstract:Objective To investigate the connection between metabolic features and ultrastructure changes in hippocampus of APP / PS1 double transgenic mice, and to confirm whether this model is appropriate for Alzheimer’s disease (AD) research. Methods A novel object recognition test was conducted to compare learning and memory in APP / PS1 mice with age- and background-matched wild type mice. Metabolic features such as N-acetylaspartate (NAA), myo-Inositol (mI), choline (Cho), and glutamate (Glu) levels in the hippocampus were assessed using proton magnetic resonance spectroscopy. Cellular ultrastructures were observed using a transmission electron microscope. Results Compared with wild type mice, APP / PS1 mice exhibited significantly decreased learning and memory ability ( P < 0. 05), a significantly reduced NAA to creatine ( Cr) ratio ( P < 0. 05), and increased mI/ Cr and Cho / Cr (P < 0. 05 ) ratios in the hippocampus. Compared with wild type mice, APP / PS1 mice had the following features: mitochondria in neurons and astrocytes were irregularly shaped and condensed, there were more secondary lysosomes, astrocytes were over-active, and there were phagocytosed dystrophic neurites. Conclusions Pathological changes in NAA, mI, and Cho in the hippocampus of APP / PS1 mice could reflect abnormal inflammation and aberrant neurites evoked by beta amyloid in AD. Thus, APP / PS1 transgenic mice may represent a beneficial model for AD research.

Abstract:Objective To examine the effect of a compound healthy ear agent (CHEA) from traditional Chinese medicine (TCM) on i) age-related apoptosis of cochlear hair cells (OHC) and spiral ganglion neurons ( SGN) using transmission electron microscopy (TEM), and on ii) localized expression of brain-derived neurotrophic factor (BDNF) and neuron-specific nuclear antigen (NeuN) to investigate mechanisms of CHEA actions. Methods Twenty-two C57BL/ 6J mice were randomly divided into two groups at 1 month of age. Eleven animals were provided tap water daily until 7 months of age; the age-related cochlear degeneration control group (7-month-old control group). Another 11 animals drank CHEA 1. 83 g / (kg·d) until 7 months of age; the TCM-treated group (7-month-old TCM group). Cochlea of euthanized animals were removed and processed into paraffin-embedded slices. Using TEM, ultrastructural changes were examined in the remaining and undisintegrated OHC and SGN associated with OHC at the basal region of cochlea from 7-month-control and 7-month-old TCM groups. Localized expression of BDNF and NeuN in SGN was observed by LCM combined with a morphological multi-overlap immunofluorescence technique, and examined using statistical analyses. Results In the 7- month-old control group, remaining and undisintegrated OHC and SGN associated with OHC in cochlea basal regions exhibited atrophied cytostomes, irregular nuclei and chromatin structure, texture structure presented vague, and high electron density; in particular, SGN were different in size and shape, significantly decreased in number, and exhibited nuclei chromatin that had disintegrated or dissolved to form vacuoles, representing the presence of apoptosis. However, the 7-month-old TCM group had no obvious apoptosis in OHC or SGN of basal cochlear regions, which exhibited more complete morphological structures and nuclei with a uniform chromatin distribution, texture structure presented clear, a lower electron density, and only individual nuclei had dissolved to form vacuoles. The localized expression levels of BDNF and NeuN in the basal cochlear region were higher (P < 0. 05) in the 7-month-old TCM versus the 7-month-control group. Conclusions Ultrastructural changes of nuclei and decreased expression of NeuN in cochlear OHC or SGN were important apoptotic features in aging cochlear neurocytes. Apoptosis in SGN was earlier than in OHC. The TCM reduced the ultrastructural changes in OHC or SGN, and increased NeuN expression in SGN, which suggests that TCM had a protective effect upon SGN, consistent with TEM observations. The mechanism of action may involve promotion of BDNF expression, which exerts a series of biological effects.

Abstract:Objective To observe the early neuroprotective effect of shenzhiling oral liquid on AD mice, andto observe the effect of shenzhiling oral liquid on the ultrastructure of myelin sheath and synapse in CA1 area ofhippocampus and the changes of special staining of myelin sheath. Methods The App / Ps1 transgenic mouse model isformed by PrP-hAppk595N / M596L single transgenic dementia model mice and PrP-hPs1dE9 single transgenicdementia model mice, which is a common disease model to study Alzheimer’ s disease. The 3-month-old App / Ps1double-transgenic mice were randomly divided into the following groups (n = 9 per group): model group, donepezilgroup [0. 92 mg/ (kg·d)], shenzheling high-dose group [50 g/ (kg·d)], shenzheling medium-dose group [25 g /(kg·d)], and shenzheling low-dose group [12. 5 g/ (kg·d)]. C57BL/6J mice of the same age and background wereused as the control group. After 3 months of continuous intragastric administration, the hippocampal CA1 tissue ofmice was obtained for electron microscopic analysis, and the ultrastructural changes of myelin sheath and synapses inthis area were observed. The myelin sheath was stained and analyzed by luxol fast blue staining of nerve myelins.Results The number of synapses in the hippocampal CA1 area was decreased in the model group compared withcontrols ( P < 0. 01); the structure of neurons showed degenerative changes, the morphology of oligodendrocytesshowed pre-apoptotic state, and the structure of myelin sheath layer collapsed. The number of synapses in thehippocampal CA1 area of mice in each drug intervention group was increased compared with the model group ( P <0. 01); the morphological structure of neurons and oligodendrocytes was relatively complete, the morphologicalstructure of neurons and oligodendrocytes was intact, the chromatin was uniform, and the myelin lamellar structure wasimproved. Luxol fast blue staining revealed that myelin fibers in the model group were significantly decreased and thestaining was lighter than that in the control group. The myelin fibers in the intervention groups were increased andstaining was deepened to different degrees. Conclusions Shenzheling oral liquid may play an early neuroprotectiverole in Alzheimer’s disease by increasing the number of synapses in the hippocampal CA1 area of App / Ps1 transgenic mice and improving the structure and morphology of myelin sheath, oligodendrocytes and neurons.

Abstract:Objective To preliminarily explore the feasibility of tree shrew as a new kind of animal model in research of amblyopia, to discuss the primary visual cortex plasticity mechanism of form deprivation in tree shrew, and to provide a theoretical basis for further understanding the mechanism of amblyopia formation and recovery. Methods Sixty 30-days old tree shrews were divided into five groups, 12 in each group: the group A had the right eye sutured for 1 month; the group B had the right eye sutured for 2 months; the group C had the left eye sutured for 1 month and then opened and the righ eye was sutured for 1 month, in other words, the group C was performed by alternating suture; the tree shrews of control group 1 (D1) were in the same age as the the group A, but fed in normal breeding environment; the tree shrews of control group 2 (D2) were at the same age of groups B and C, but fed with a normal diet. Samples of the visual cortex were taken after the completion of modeling, and were processed to observe the histology and ultrastructure of the visual cortex, the neuron apoptosis, and the c-fos protein expression in the tree shrews of different groups. Results Damages to different degrees were found by histological and electron microscopic examination of the visual cortex in each experimental group, and they were more obvious in the group sutured for 2 months. TUNEL staining showed that there were no significant differences between the apoptosis in the experimental and control groups. The expression of c-fos mRNA and protein in the experimental groups was decreased, and it was the lowest in the group sutured for 2 months. There was a small increase in the c-fos expression after the alternate suture, and no significant difference of c-fos expression was found in the control groups. Conclusions Different degrees of deprivation amblyopia lead to different histopathological changes. There is a plasticity in the neurons affected by amblyopia. Tree shrew can be used as an ideal animal model for the studies of form deprivation amblyopia.

Abstract:Objective To clarify the impairment mechanisms of acute hyperglycemia in the first-phase insulin secretion in mice. Methods The mouse model of acute glucose toxicity was established by glucose infusion through jugular vein catheterization. The glucose and insulin levels were assessed by IPGTT and OGTT in the mice of acute hyperglycemia and control groups. The histology of pancreatic islets was observed using HE staining and the insulin granules and other cytoplasmic organelles were observed by electron microscopy.Results The mouse model of acute hyperglycemia was successfully established. The IPGTT showed that the blood glucose level was decreased by 87% (10.3±0.33 mmol/L vs. 19.3±1.66 mmol/L) at 15 min in the acute hyperglycemia group compared with the control group. The OGTT showed that the blood glucose level was decreased by 85% (9.8±0.31 mmol/L vs. 18.16±1.01 mmol/L) at 30 min in the acute hyperglycemia group compared with the control group. However, the peak values of insulin secretion were delayed in both IPGTT and OGTT. Insulin levels at 2.8 and 16.7 mmol/L glucose stimulation in the acute hyperglycemia group was declined by 46% and 67% than the control group, respectively (P<0.05). Residual insulin content in islet β cells was declined by 49% at 2.8 mmol/L and 94% at 16.7 mmol/L glucose infusion than the control group (P<0.05). The histology showed irregular structure of pancreatic islets in the acute hyperglycemia group. The electron microscopy revealed that the amount of insulin granules was decreased, and more cytoplasmic vacuoles and swollen mitochondria were observed.Conclusions Acute intravenous glucose load decreases insulin content of islet β cells, leading to decrease and delay of the first-phase insulin secretion.

Abstract:Objective To observe the changes of mRNA expression related to kidney yang deficiency and the ultrastructure of hypothalamus in Lewis rats, and further study the constitution of kidney yang deficiency in Lewis rats. Methods Ten 7-8-week old SPF male Lewis rats and twenty 7-8-week old SPF male Wistar rats were used in this study. The rats received subcutaneous injection of hydrocortisone to establish kidney yang deficiency model. The expressions of TNF-α, IFN-γ, IL-10, CRH, MR and GR mRNA in the hypothalamus of the two groups were detected and the ultrastructural changes of hypothalamus and adrenal gland were observed to compare the differences between the two groups, and to explore the mechanism of kidney yang deficiency constitution in the Lewis rats. Results Compared with the normal Wistar rats, the expressions of GR and IL-2 mRNA in the hypothalamus were significantly increased (P<0.01), while the expressions of CRH, TNF-α, IFN-γ and IL-10 mRNA were significantly decreased in the Lewis rats (P<0.01). The zona fasciculata of the adrenal cortex was slightly thinner, the mitochondria were slightly swollen and the amount of mitochondria was decreased. The nuclei of hypothalamic neurons were larger, and the mitochondria, neuron synapses and secretory vesicles in the presynaptic neurons were decreased. Conclusions There are abnormal expression of immune-related cytokines and CRH mRNA, and ultrastructural changes in the hypothalamus and adrenal gland of Lewis rats with kidney yang deficiency. Such changes may be related to the functional imbalance of the hypothalamus-pituitury-adrenal axis.

Abstract:Objective The aim of this study was to investigate the differences of the cell ultrastucture of normal mouse hatched blastocysts and their dormant ones cultured in vitro after freezing-thawing, and to explore whether the dormant embryos have a better anti-freezing shock property than the normal hatched mouse embryos. Methods By transmission electron microscopy, the ultrastructure of these two types of mouse embryos was observed and analyzed. Results By comparative analysis of their ultrastructure, the results showed that the dormant embryos before freezing are being austerity and with lower energy metabolism at a‘ground state. After freezing-thawing and culture, their cellular structure seemed to be similar to that of the normal embryos cultured in vitro before freezing. However, after freezing-thawing and culture, the number of mitochondria decreased, the nuclei were loose, and their heterochromatin also increased. Conclusions From the ultrastructural observation, compared with the normal mouse hatched embryos, the cellular state of dormant mouse embryos after freezing-thawing is more favorable for material storage and energy metabolism, thus, indicating that they have a better anti-freezing property than normal hatched embryos.

Abstract:Objective To investigate the effect of soybean isoflavone on histology and uhrastructure of benign prostatic hyperplasia in rats.Methods Male SD rats were injected subcutaneously testosterone propionate for 28 d to induce prostatic hyperplasia,and the rats were divided into 5 groups:control group,model group,and 3 test groups with SI in a dose of 60 mg/(kg·d),120 mg/(kg·d) and 240 mg/(kg·d),respectively.The wet prostate weight,prostatic index,morphological,uhrastmetural and morphometrie changes of the prostatic shndular and interstitial tissues were observed.Results The prostate wet weight,prostatic index and prostatic volumes in all dose groups were significantly lower than those in the models.In comparison with the model group,height of prostatic epithelial cells,glandular average diameters,volumes and surface areas in unit volume,as well as glandular circumferences,glandular relative total volumes and interstitial relative total volumes were all significantly decreased.Glandular counts,density,ratio of glandular surface area to volume,and glandular average curvature were all increased.Conclusions Soybean isoflavone can inhibit prostatic hyperplasia in rats.

Abstract:Objective During an electron microscopic investigation on peripheral blood cells of Hapalogenys nitens,a large number of intranuclear inclusions in neutrophils were found.The aim of this study was to carry out a further ultrastructural observation on these inclusions.Methods The intranuclear inclusions in neutrophils were examined by transmission electron microscopy.Results The intranuclear inclusions in neutrophils could be subdivided into pseudo and true inclusions.The inclusion bodies contained materia...