BACKGROUND: Atrial natriuretic peptide (ANP)-synthesizing cells distribute in all over the body. However, very little is known about the morphological localization and the distribution characteristics of ANP-synthesizing cells in different regions of rat stomach. OBJECTIVE: To investigate the ultrastructural localization and distribution characteristics of ANP-synthesizing cells in rat stomach. DESIGN: Repeated measurement experiment. SETTING: Chengde Medical Collage, Chengde, Hebei Province, China. MATERIALS: This study was performed at the Laboratory for Institute of Chinese Materia Medica Immunology (provincial key laboratory), Chengde Medical College between October 2004 and July 2007. Eighteen adult Wistar rats of either gender, weighing 175-300 g, were provided by the Laboratory Animal Center of Chengde Medical College. The disposal of animals was conducted in accordance with ethical guidelines for the use and care of animals. ANP antibody and serum (Santa Cruz Biotechnology, Inc, USA), Protein A-15 nm colloidal gold labeled (Sino-American Biotechnology Company, China), CMIAS image analysis system (Beijing University of Aeronautics and Astronautics, China) and JEM-1200EX transmission election microscope (Japan) were used in the study. METHODS: After gastric and right atrial tissues (as a positive control in immanohistochemical staining for ANP-synthesizing cells) were fleshly excised from anesthetized Wistar rats, the specimens were longitudinally harvested along rat gastric cardiac region, gastric fundic mucosa and gastric pyloric region. Gastric tissue was performed immunohistochemical staining (for positive control) together with right atrial tissue, to observe the distribution characteristics of ANP-synthesizing cells in different regions of rat gastric tissue, and to localize ANP-synthesizing cells. The ultrastructural localization of ANP-synthesizing cells in the rat gastric mucosa was performed by postembedding immunoelectron microscopy. The area-density percentage of ANP-synthesizing cells in the different regions of rat stomach (gastric cardiac region, pyloric region and fundic region) was calculated with a CMIAS image analysis system. MAIN OUTCOME MEASURES: Morphological appearance and localization of ANP-synthesizing cells as well as the different area-density percentage in different regions of rat stomach. RESULTS: As a positive control, ANP-synthesizing cells showed intense positive expression in atrial myocytes and cytoplasm and in gastric mucosa (mainly within the lower third of rat gastric mucosa). The morphological appearance of the individual ANP-synthesizing cell was variable, exhibiting round, pyramidal and flask shapes. Negative staining for ANP-synthesizing cells was detected in the lamina propria, submucosa, and smooth muscle. ANP-synthesizing cells existed in different regions of rat stomach and its area-density was the largest in the pyloric region. The distribution order of ANP-synthesizing cells in area-density was gastric cardiac region > gastric pyloric region > gastric fundic mucosa in mucosa layer. CONCLUSION: ANP-synthesizing cells mainly exist within the lower third of the rat gastric mucosa. The percentage of area-density of ANP-synthesizing cellswas variable in different regions of rat gastric mucosa, and its percentage of area-density was the largest in the gastric cardiac region.

Objective To investigate relationship between the expressions of TGF-β1 mRNA, Smad7 mRNA and ki-67 mRNA and the clinicopathologic characteristics in gastric carcinoma. Methods 60 cases with gastric carcinoma tissue and 20 cases with normal gastric tissue, which were surgically removed and certified by pathology, were collected. The expressions of TGF-β1 mRNA, Smad7 mRNA and ki-67 mRNA were detected by RT-PCR in normal and carcinomatous gastric tissue. Results The expressions of TGF-β1 mRNA, Smad7 mRNA and ki-67 mRNA in normal gastric tissue were lower than those in carcinomatous gastric tissue (P < 0.05). The expressions of TGF-β1 mRNA, Smad7 mRNA and ki-67 mRNA in gastric carcinoma which were well differentiated and moderately differentiated were significantly lower than those in poorly differentiated gastric carcinoma (P<0.05). The expressions of TGF-β1 mRNA, Smad7 mRNA and ki-67 mRNA in gastric carcinoma without lymph node metastasis were lower than those in gastric carcinoma with lymph node metastasis. The expressions of TGF-β1 mRNA, Smad7 mRNA and ki-67 mRNA in Ⅰ+Ⅱ stage were lower those in Ⅲ+Ⅳ stage (P < 0.05). Linear correlation showed there were positive correlations among TGF-β1 mRNA, Smad7 mRNA and ki-67 mRNA in gastric carcinoma. Conclusions The canonical TGF-β1 Smad7 and Ki-67 mRNA play a role in the carcinogenesis, development, differentiation of gastric carcinoma.

BACKGROUND: Development of liver fibrosis accompanies many morphological and functional changes. The pathological alterations of dimethylnitrosamine (DMN)-induced liver fibrosis in rats are similar to those of human liver fibrosis.OBJECTIVE: To observe the dynamic changes in morphology and serum hyaluronic acid (HA), laminin (LN), and type Ⅳ collagen in rats with liver fibrosis induced by DMN.DESIGN: Randomized controlled animal trial.SETTING: Laboratory of Teaching and Research Section of Pathology, College of Medicine, Yanbian University.MATERIALS: Eighty 3-month-old male rats of clean grade with 175-200 g body mass were selected, which were provided by the animal center of College of Medicine, Yanbian University. Agents: Dimethylnitrosamine provided by Sigma company, α smooth muscle actin by Dako company, Sirius red by Aldrich chem company, serum hyaluronic acid,laminin and type Ⅳ collagen kit by Sino-American Biotechnology Company, rabbit-anti-rat I g by Dako, Denmak company. Devices: JEM-1200EX transmission electron microscope made in Japan; enzyme linked immuno analyzer made in Japan; and CMTAS multifunction true color pathological image analysis system developed by Beijing University of Aeronautics and Astronautics.METHODS: The experiment was conducted in the College of Medicine, Yanbian University from June 2004 to December 2005. The rats were divided into 2 groups by lot: model group (n =40): The rats were intraperioneally injected with 10 g/L DMN (10 μL/kg) once daily, 3 days a week for 4 weeks; control group (n =40): The matching normal saline was injected at the same period; the blood from the left ventricle was collected and frozen in refrigerator at -70 ℃ before the rats were killed at days 7, 14, 21, and 28 and the liver tissue was removed for electron and light microscope observation. ①The dynamic changes in the content of serum HA, LN and type Ⅳ collagen were measured by enzyme-linked immunoabsorbent assay (ELISA). ②The morphological changes and liver fibrosis grading were examined by HE staining,immunohistochemical Sirius-red staining (liver fibrosis degree was classified into 5 grades: grade 0: no fibrosis; grade 1:fibrosis in portal area; grade 2: fibrotic septa between portal tracts; grade 3: fibrosis septa and structure disturbance of hepatic lobule; grade 4: cirrhosis), meanwhile, the area-density percentage of collagen fibrosis was calculated. ③The hepatic stellate cells were detected with transmission electron microscope and immunohistochemical alpha smooth muscle actin (SMA) staining. ④The correlation between area-density percentage of collagen fibrosis during liver fibrosis formation and the serum levels of HA, LN and type Ⅳ collagen was analyzed.MAIN OUTCOME MEASURES: ①The changes in the serum levels of HA, type Ⅳ collagen and LN during liver fibrosis formation; ②The morphological changes and liver fibrosis grading and area-density percentage of collagen fibrosis; ③Transformation and distribution characteristics of hepatic stellate cells; ④The correlation between area-density percentage of collagen fibrosis and the serum levels of HA, LN and type Ⅳ collagen.RESULTS: Among the 80 rats, 34 of the experimental group were modeled successfully, which were involved in the result analysis with the 40 rats in the control group. ①The levels of serum HA, type Ⅳ collagen and LN of the model group were significantly higher compared with the control group from day 7 to 28 (P ＜ 0.05), especially that on the 28th day. ②In the model group, the portal area of the rats showed hemorrhagic necrosis at day 7 after injection of DMN; at day 14,hemorrhage, necrosis and thin fibrotic septa joining central areas of liver were found; at days 21 and 28, thick septa was found; The area-density percentage of collagen fibrosis of the model group was significantly higher compared with the control group at days 7, 14, 21 and 28 (P ＜ 0.05), especially that on the 28th day. There were significant differences in the liver pathologic grading between the two groups at each time point (P ＜ 0.01); the pathologic grading of the model group at day 7 differed from those at days 14 and 28 (P ＜ 0.01). ③The α-SMA positive cells and a transitional hepatic stellate cell were found under the electron microscopy; typical myofibroblast was observed in the model group at day 21 and 28 under the electron microscopy. ④The area-density percentage of collagen fibrosis was positively correlated with the content of serum HA, LN and type Ⅳ collagen (r=0.707, 0.675, 0.662, P＜ 0.01).CONCLUSTON: There are significantly progressional changes in morphological and serum levels of HA, type Ⅳ collagen and LN in different stages of DMN-induced liver fibrosis in rats, moreover, the area-density percentage of collagen fibrosis is positively correlated with the serum levels of HA, LN and type Ⅳ collagen at different stages.

BACKGROUND: Previous studies have confirmed that atrial natriuretic peptide (ANP) exists in different regions of rat gastric mucosa in different densities, and ANP can inhibit the spontaneous contraction of gastric smooth muscles in rat, guinea pig and human.OBJECTIVE: To investigate the ultrastructural localization of ANP-synthesizing cells and the correlation between ANP-synthesizing cells and microvessel density in rat gastric mucosa.DESIGN: Single sampling study.SETTING: Affiliated Hospital of Chengde Medical College. MATERIALS: Eighteen adult male Wistar rats of clean grade, weighing 300-350 g, were used in this study.METHODS: This study was conducted in the Laboratory of Chinese Materia Medica Immunology, Chengde Medical College from October 2004 to July 2007. The ultrastructural localization of ANP-synthesizing cells in rat gastric mucosa was performed by postembedding immunoelectron microscopy technique. The area density of ANP-synthesizing cell distribution was calculated by histochemical technique (saffron solution and toluidine solution staining included). Microvessels of rat gastric mucosa were revealed distinctively by tannic acid-ferric chloride staining method and scanning electron microscope technique.MAIN OUTCOME MEASURES:①The ultrastructural localization of ANP-synthesizing cells in rat gastric mucosa.②The distribution characteristics of gastric microvessels in different regions of rat gastric mucosa.③The distribution characteristics of ANP-synthesizing cells in rat gastric mucosa.④Correlation between ANP-synthesizing cell distribution and microvessel density.RESULTS: ① Ultrastructural localization of ANP-synthesizing cells: It was confirmed that ANP-cells were the enterochrochromaffin (EC) cells. ② Observation of microvessels: The microvessels were stained successfully by tannic acid-ferric chloride and scanning electron microscope technology. Microvessels of gastric mucous were in wriggled way and cut in different cross-sections. They could be clearly observed in distinct three-dimensions. The microvessel density was the largest in the basal glands of rat gastric mucous. ③ Distribution of ANP-synthesizing cells: It was identified that EC cell was only a chromaffin cell in the rat gastric mucosa. The chromaffin granules (brown granules) were localized in the cytoplasm of EC cells. Negative staining for chromaffin granules was detected in the submucosa and smooth muscle. EC cells had different distribution densities in different regions. The density order of EC cells was gastric cardiac region ＞ gastric pyloric region ＞ gastric fundic region in mucosal layer. ④ Correlation between ANP-synthesizing cells and microvessel density: Correlation analysis showed that there was a positive correlation between ANP-synthesizing cells and microvessel density in the gastric cardiac region(r = 0.53, P ＜ 0.05, n=18), and there was a negative correlation between above-mentioned two indices in the gastric pyloric region(r = 0.38, P ＞ 0.05 , n=18)and in the gastric fundic region(r = -0.29, P ＞ 0.05, n=18).CONCLUSION: ANP-synthesizing cells are the EC cells of gastric mucosa. There is a positive correlation between ANP-synthesizing cells and microvessels in the rat gastric cardiac region, while there is a negative correlation between ANP-synthesizing cells and microvessels in the rat gastric pyloric region and in the gastric fundic region.

BACKGROUND: Previous researches have proved that both atrial natriuretic polypeptide (ANP) and 5-hydroxytryptamine (5-HT) exist in the same endocrine granule of enterochromaffin cell (EC). However, whether ANP may promote or inhibit synthesis and secretion of 5-HT needs to be further studied. OBJECTIVE: To investigate the effect of ANP on synthesis and secretion of 5-HT in EC of rat gastric mucosa.DESIGN: Randomized controlled animals study.SETTING: Immunology Laboratory, Chengde Medical College. MATERIALS: This study was performed at the Immunology Laboratory, Chengde Medical College from October 2004 to July 2007. Forty adult male Wistar rats were provided by the Experimental Animal Center of Chengde Medical College. The experiment was in accordance with animal ethics standards. ANP, 5-HT antibody and serum were provided by Santa Cruz Biotechnology Company, USA.METHODS: Forty rats were randomly into endocrine and exocrine groups, and rats in the two groups were sub-grouped into control and experimental groups with 10 in each group. ANP (28 μg, 14 mg/L) was directly injected into the stomach to mimic ANP luminal secretion and ANP (14 μg, 14 mg/L) was directly injected into the sublingual vein to mimic ANP endocrinal secretion. In above condition, 5-HT immunoreactive positive cell was displayed by using immunohistochemistry technique, numerical density (Nv) of endocrine granule (SG) was counted by using electron microscopic morphometry, and 5-HT level in the serum was measured by using HPLC-ECD technique. And then, the results were compared to the control group. MAIN OUTCOME MEASURES: Effects of ANP on density of 5-HT immunoreactive positive cell, numerical density (Nv) of SG and 5-HT level in the serum. RESULTS: Effect of luminal and endocrine ANP on the 5-HT secretion: The density of immunoreactive positive cell and the numerical density (Nv) of SG were significantly increased by luminal and endocrine ANP (P＜0.05), while 5-HT level in serum was significantly reduced by luminal and endocrine ANP (P＜0.05). CONCLUSION: Luminal and endocrinal ANP can inhibit 5-HT release of gastric mucosa but may not change or enhancement its synthesis in rat.

Objective To investigate the expression of SOX2,TGF-β1 and Smad3 in gastric cancer and their relationships with clinical pathological characteristics of gastric cancer. Methods Immunohistochemical staining was used to detect the expression of SOX2, TGF-β1 and Smad3 expression and the clinical pathological characteristics of gastric cancer were analyzed. Results Integrated optical density (IOD) values from the positive expression of SOX2, Smad3 in gastric cancer group were all significantly lower than normal gastric tissues (P < 0.05). IOD values from the positive expression of TGF-β1 in gastric cancer group were all significantly higher than normal gastric tissues (P < 0.05). IOD values from the positive expression of TGF-β1 in lower poorly differentiated gastric cancer tissues, with lymph node metastasis and Ⅲ+Ⅳ were all significantly higher (P < 0.05). Higher IOD values from expression of SOX2 and Smad3 were found in high-moderated differentiated gastric cancer tissues, without lymph node metastasis and Ⅰ+Ⅱgastric cancer (P < 0.05). SOX2, TGF-β1 and Smad3 in gastric cancer has nothing to do with age illness and sex (P >0.05). There was positive correlation between SOX2 and Smad3 expression in gastric cancer tissues, and negative correlation between TGF-β1 and Smad3 in gastric cancer. Conclusions Abnormal expression of SOX2, TGF-β1 and Smad3 protein is related to the onset, development and clinicopathologic features of gastric cancer.

Aim To explore the influence of metformin(a first-line drug for type 2 diabetes) on ATP-induced inflammasome activation and the release of interleukin-1β(IL-1β) by LPS-activated peritoneal macrophages, a commonly-used inflammatory cell model.Methods Peritoneal macrophages were elicited by intraperitoneal injection of 30 g·L-1 thioglycollate into C57BL/6 mice.Inflammasome was activated and cell pyroptosis was induced by LPS plus ATP treatment, and the pyroptotic cells were calculated after propidium iodide(PI) staining.The protein levels of IL-1β and caspase-1 expressed in the cells and released from them into the supernatant were evaluated by Western blot.Immunofluorescent microscopy was recruited to detect the subcellular distribution and fluorescent intensity of the purinergic P2X7 receptor(P2X7R).Results Metformin per se did not induce pyroptosis in LPS-activated peritoneal macrophages, but it significantly and dose-dependently increased cell pyroptosis induced by ATP treatment.At protein levels, maturated IL-1β(17 ku) could not be released from the cells upon single LPS or LPS plus metformin stimulation;but after ATP was added, maturated IL-1β was released into the supernatants of the cells.Moreover, metformin dose-dependently increased the protein levels of both maturated IL-1β and active caspase-1 released by the LPS-activated peritoneal macrophages upon ATP stimulation.Conclusion Metformin intensifies the activation of inflammasome and increases the release of active caspase-1 and maturated IL-1β upon ATP stimulation in the LPS-activated peritoneal macrophages, which should promote inflammatory responses.

Objective To study the effects of using the polysiloxane impression material in the repair of the precise attachment.Method Using the Rapid polysiloxane impression material to make 37 work impressions,29 un-work impressions were made by alginate impression material.Results All the work impressions were eligible while there were 4 un-work impressions not eligible at the first time. Conclusion The effects of using the polysiloxane impression material in the repair of the precise attachment is satisfactory.

Aim To study the mechanism of cucurb-itacin E ( CuE )-induced autophagy in HeLa cells. Methods Improved MTT assay was adopted to meas-ure the effect of CuE on cell proliferation. Western blot was used to determine the phosphorylation levels of downstream signaling proteins of mTORC1 and the ex-pression of autophagy associated proteins. ResultsCuE inhibited the proliferation of HeLa cells in a dose-dependent manner, and the 24-h IC50 of CuE was 4. 01μmol· L-1 . CuE significantly inhibited the phospho-rylation of p70 S6 K in a time-and dose-dependent man-ner as evidenced by decreased phosphorylation levels of
the mTORC1 substrate. Meanwhile, the expression of LC3-II, a marker for autophagosome formation, was elevated by CuE treatment, and was further increased in the presence of chloroquine. Furthermore, CuE re-duced the levels of p62/SQSTM1 . These results indi-cated that CuE induced autophagy in HeLa cells. The decreased levels of phosphorylated ULK1 S757 were posi-tively correlated with autophagy induction in HeLa cells. Conclusion CuE is likely to induce autophagy through inhibiting mTORC1 activity.

Objective To study on the clinical application and value of double-balloon video en teroscopy in diagnosing small inlestinal bleeding. Methods Fifty-four cases with suspected small intestinal bleeding were subjected to double-balloon video enteroscopy, via the mouth and /or anus in 21, 20 and 13 cases respectively, the procedure was performed under X-ray monitoring. Results The positive rate of en-doscopy was 90. 7% , the findings were isolated or multi small intestinal ulcer 11 cases, Crhon' s disease 7 cases; chronic nonspecific inflammation 6 cases, entero-mesenchymoma 6 cases; high differentiated adeno-carcinoma 3 cases; polyps 2 cases, lymphoma 1 case, stero-pro-nematodiasis 2 cases, ancylostomiasis 2 cases, vascular deformity 2 cases ( 1 with active hemorrhage) , Michael diverticulosis 2 case, iliac polydivertic ulosis 1 case, ulcerative colonitis 1 case, duodenal stasis I case, duodenal ulcer 2 cases and essentially normal 5 cases. Complications related to the procedure never occurred. Conclusions The main causes of small intestinal bleeding are benign ulcers and tumor, as well as chronic inflammation. Parasitosis is the fourth cause. Diverticulosis and vascular deformity are the rare cause. But Michael diverticulosis is an important cause for the children with small intestinal bleeding., Double-balloon video enleroscopy is the most valuable method in diagnosing small intestinal diseases.