Influence of total flavonoids derived from Choerospondias axillaris folium on aconitine-induced antiarrhythmic action and hemodynamics in Wistar rats.

It is well known that various traditional Chinese medicines produce antiarrhythmic actions. The aims of this study were to examine whether total flavones derived from Choerospondias axillaris folium (TFCF) also produced antiarrhythmic effects using a rat model of aconitine-induced arrhythmia and to compare these observations with the effects of total flavones of Choerospondias axillaris fructus (TFC). Wistar rats were orally administered TFC (0.2 g/kg) or TFCF (0.1, 0.2, or 0.4 g/kg) daily for 7 d. Subsequently, aconitine iv at 25 µg/kg was used to induce arrhythmia in these animals. Control (C) physiological saline and positive verapamil rats were also administered orally. The starting times of ventricular ectopic beats (VE), ventricular tachycardia (VT), ventricular fibrillation (VF), and heart arrest (HA) were recorded. In comparison to C, TFCF and TFC significantly prolonged the starting time of VE, VT, VF, and HA induced by aconitine. With respect to hemodynamics, TFC and high-dose TFCF were effective in reducing HR without associated changes in BP in all groups. TFC and TFCF decreased left ventricular systolic pressure (LVSP) and maximal velocity rate of ventricular pressure (+dp/dt max and -dp/dt min) with no marked effect on left ventricular end diastolic pressure (LVEDP) and -dp/dtmin. Data demonstrated that TFCF and TFC were equally effective in diminishing the aconitine-mediated arrhythmias. In addition, TFCF and TFC produced a similar reduction in HR with no accompanying change in BP. These findings indicate that the TFCF- and TFC-induced alterations may be attributed to inhibition of ventricular contraction without altering ventricular diastolic function.

[Research on Multi-Spectral Target Recognition System Based on the Magneto-Optical Modulation].

The technology of target recognition based on characteristic multi-spectrum has many advantages, such as strong detection capability and discriminating capability of target species. But there are some problems, it requires that you obtain the background spectrum as a priori knowledge, and it requires that the change of background spectrum is small with time. Thereby its application of real-time object recognition is limited in the new environment, or the complex environment. Based on magneto-optical modulation and characteristic multi-spectrum the method is designed, and the target is identified without prior access to the background spectrum. In order to achieve the function of the target information in the one acquisition time for tested, compared to conventional methods in terms of target detection, it's adaptability is better than before on the battlefield, and it is of more practical significance. Meanwhile, the magneto-optical modulator is used to suppress the interference of stray light background, thereby improving the probability of target recognition. Since the magneto-optical modulation provides incremental iterative target spectral information, therefore, even if the unknown background spectrum or background spectrum change is large, it can significantly improve the recognition accuracy of information through an iterative target spectrum. Different test targets back shimmering light intensity and background intensity values were analyzed during experiments, results showed that three targets for linearly polarized reflectance modulation is significantly stronger than the background. And it was of great influence to visible imaging target identification when measured target used camouflage color, but the system of polarization modulation type can still recognize target well. On this basis, the target range within 0.5 km x 2 km multi-wavelength characteristics of the target species were identified. When using three characteristic wavelengths, the probability of target identification significantly reduced at around 2km, when using four or five characteristic wavelength position, the probability of target identification reach up to more than 95.0%. Meanwhile, in order to reduce the calculation and improve the real-time detection capability of the system, finally, four characteristic wavelengths was selected. So the system has a certain application value.

The effect and mechanism of bufalin on regulating hepatocellular carcinoma cell invasion and metastasis via Wnt/ß-catenin signaling pathway.

Hepatocellular carcinoma (HCC) is a highly malignant tumor with an extremely poor prognosis. Our preliminary study indicated that bufalin could restrain the proliferation of human hepatoma BEL-7402 cells in a time- and dose-dependent manner. In the present study, the colony formation assay, the Transwell invasion assay, the western blot analysis and the immunofluorescence method were respectively used to investigate the effect and mechanism of bufalin against HCC cell invasion and metastasis. We found that: i) bufalin had significant inhibitory effect on the cell proliferation of BEL-7402 cells; ii) bufalin markedly inhibited the migration and invasion of BEL-7402 cells; iii) bufalin could suppress the phosphorylation of GSK-3ß Ser9 site in BEL-7402 cells, decrease the expression of ß-catenin, cyclin D1, metalloproteinases-7 (MMP-7) and cyclooxygenase-2 (COX-2) in the cytoplasm, and increase the expression of E-cadherin and ß-catenin on the cell membrane; and iv) the expression of α-fetoprotein significantly decreased and the expression of albumin increased in BEL-7402 cells after bufalin was used. Our results indicate that: i) bufalin can regulate the expression of associated factors in Wnt/ß-catenin signaling pathway of BEL-7402 cells through suppressing the phosphorylation of GSK-3ß Ser9 site; ii) bufalin can strengthen intercellular E-cadherin/ß-catenin complex to control epithelial-mesenchymal transition; and iii) bufalin can reverse the malignant phenotype and promote the differentiation and maturation by regulating the AFP and ALB expression in BEL-7402 cells. These are very important mechanisms of bufalin on the inhibition of the invasion and metastasis of HCC cells.

Tanshinone II--a inhibits angiogenesis through down regulation of COX-2 in human colorectal cancer.

Angiogenesis plays a significant role in colorectal cancer (CRC) and cyclooxygenase-2 (COX-2) appears to be involved with multiple aspects of CRC angiogenesis. Our aim was to investigate the inhibitory effects of Tan II-A (Tanshinone II-A, Tan II-A) on tumor growth in mice, as well as alteration of expression of COX-2 and VEGF in CRC. We established the mice xenograft model of C26 CRC cell line, and injected 0.5, 1, 2mg/kg of Tan II-A and 1mg/kg of 5-FU in respectively in vivo. Then, we assayed tumor weight and volume, and evaluated microvascular density and expression of VEGF. COX-2 promoter and COX-2 plasmids were transfected into HCT-116 cells, followed by detection of COX-2 promoter activity by chemiluminescence, and detection of COX-2 mRNA expression by fluorescence quantitative PCR. Taken together, the results showed Tan II-A could inhibit tumor growth and suppress the VEGF level in vivo. HCT-116 cell experiments showed marked inhibitory effects of Tan II-A on COX-2 and VEGF in a dose-dependent manner. The results indicate that Tan II-A can effectively inhibit tumor growth and angiogenesis of human colorectal cancer via inhibiting the expression level of COX-2 and VEGF.

Analysis of risk factors for polypoid lesions of gallbladder among health examinees.

AIM: To investigate the prevalence and risk factors of polypoid lesions of gallbladder (PLG) among the health examinees in the Shanghai region, China. METHODS: A total of 11,816 subjects who underwent health examinations in our hospital between August 2010 and February 2011 were analyzed retrospectively. Among them, there were 7174 men and 4642 women. PLG was diagnosed by the real-time ultrasonography. Those with the body mass index (BMI) ≥ 28 were considered to be obese. Blood biochemical indices were detected with the fully automatic biochemical analyzer and hepatitis B surface antigen (HBsAg) was tested by the automated enzyme immunoassay. The correlations between the prevalence of PLG and age, sex, BMI, serum cholesterol (T-Cho), triglycerides (TG), blood sugar, HBsAg, high-density lipoprotein (HDL-C), low-density lipoprotein (LDL-C), gallstone and fatty liver were investigated. After univariate analysis of 11 variables, stepwise logistic regression analysis was performed to explore the risk factors of PLG. RESULTS: There was a significant difference in sex, T-Cho, HBsAg, HDL-C, LDL-C and fatty liver between the PLG-positive group and the PLG-negative group (332/163 vs 6842/4479, P = 0.003; 22/473 vs 295/11,026, P =0.013; 92/403 vs 993/10,328, P = 0.001; 47/448 vs 332/10,989, P = 0.001; 32/463 vs 381/10,940, P = 0.001; 83/412 vs 3260/8061, P = 0.001). No significant difference was found in the age, BMI, TG, blood sugar and gallstone between the two groups (47.3 ± 26 vs 45.1 ± 33, P = 0.173; 59/436 vs 1097/10,224, P = 0.102; 52/443 vs 982/10,339, P = 0.158; 17/478 vs 295/11,026, P = 0.26; 24/471 vs 395/10,926, P = 0.109). Logistic regression analysis showed that the sex, HBsAg and HDL-C were independent risk factors for the development of PLG in a descending order of HDL-C > HBsAg > sex. CONCLUSION: In healthy people, the male gender, positive HBsAg, and low HDL-C confer higher risks of PLG development.

Anti-tumor effects of brucine immuno-nanoparticles on hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma is difficult to diagnose early, and most patients are already in the late stages of the disease when they are admitted to hospital. The total 5-year survival rate is less than 5%. Recent studies have showed that brucine has a good anti-tumor effect, but high toxicity, poor water solubility, short half-life, narrow therapeutic window, and a toxic dose that is close to the therapeutic dose, which all limit its clinical application. This study evaluated the effects of brucine immuno-nanoparticles (BIN) on hepatocellular carcinoma. MATERIALS AND METHODS: Anionic polymerization, chemical modification technology, and phacoemulsification technology were used to prepare a carboxylated polyethylene glycol-polylactic acid copolymer carrier material. Chemical coupling technology was utilized to develop antihuman AFP McAb-polyethylene glycol-polylactic acid copolymer BIN. The size, shape, zeta potential, drug loading, encapsulation efficiency, and release of these immune-nanoparticles were studied in vitro. The targeting, and growth, invasion, and metastasis inhibitory effects of this treatment on liver cancer SMMC-7721 cells were tested. RESULTS: BIN were of uniform size with an average particle size of 249 ± 77 nm and zeta potential of -18.7 ± 4.19 mV. The encapsulation efficiency was 76.0% ± 2.3% and the drug load was 5.6% ± 0.2%. Complete uptake and even distribution around the liver cancer cell membrane were observed. CONCLUSION: BIN had even size distribution, was stable, and had a slow-releasing effect. BIN targeted the cell membrane of the liver cancer cell SMMC-7721 and significantly inhibited the growth, adhesion, invasion, and metastasis of SMMC-7721 cells. As a novel drug carrier system, BIN are a potentially promising targeting treatment for liver cancer.

Anti-tumor activity and apoptosis-regulation mechanisms of bufalin in various cancers: new hope for cancer patients.

The induction of apoptosis in target cells is a key mechanism for most anti-tumor therapies. Bufalin is a cardiotonic steroid that has the potential to induce differentiation and apoptosis of tumor cells. Research on bufalin has so far mainly involved leukemia, prostate cancer, gastric cancer and liver cancer, and has been confined to in vitro studies. The bufadienolides bufalin and cinobufagin have been shown to induce apoptosis in a wide spectrum of cancer cell. The present article reviews the anticancer effects of bufalin. It induces apoptosis of lung cancer cells via the PI3K/Akt pathway and also suppressed the proliferation of human non-small cell lung cancer A549 cell line in a time and dose dependent manner. Bufalin, bufotalin and gamabufotalin, key bufadienolides, significantly sensitize human breast cancer cells with differing ER-alpha status to apoptosis induction by the TNF-related apoptosis-inducing ligand (TRAIL). In addition, bufadienolides induce prostate cancer cell apoptosis more significantly than that in breast epithelial cell lines. Similar effects have been observed with hepatocellular carcinoma (HCC) but the detailed molecular mechanisms of inducing apoptosis in this case are still unclear. Bufalin exerts profound effects on leukemia therapy in vitro. Results of multiple studies indicate that bufalin has marked anti-tumor activities through its ability to induce apoptosis. Large-scale randomized, double-blind, placebo or positive drug parallel controlled studies are now required to confirm the efficacy and apoptosis-inducing potential of bufalin in various cancers in the cliniucal setting.

[Based on Moire interference accurate detection of the laser center wavelength].

To improve spectrum resolution of the traditional Fourier interferometer with the same size lens, was proposed based on orthogonal wedge Fourier interferometer system. The interferometer system gets the optical path difference by the prism of two mutually perpendicular, which can make the laser Interferences on the CCD Array. The detector use the area array CCD linear array CCD, and the system collected the interference fringes on the two-dimensional plane. On the basis of the spectrum distribution of orthogonal inclination Moire interferometer by calculating optical path difference function, the system made the splicing of interference fringes on the area array CCD and Moire transform, finally got the spectrum resolution. The results from the MATLAB simulation software shows that the Maximum optical path difference of the orthogonal inclination Moire interferometer can be generated up to 234 microm, which is higher than the traditional Fourier interferometer about one order of magnitude, so the spectrum resolution also increased by nearly 10 times theoretical. Experimental calibration of the spectrometer with a selection of LAB SPAKR 750A-type spectrometer, measurements for the center wavelength of 635 nm semiconductor laser, the results show basically the same center wavelength position. However, the spectrum detected by orthogonal inclination Moire interferometer system near the center wavelength is better than the traditional interferometer system.

Comparative proteomics analysis of human gastric cancer.

AIM: To isolate and identify differentially expressed proteins between cancer and normal tissues of gastric cancer by two-dimensional electrophoresis (2-DE) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). METHODS: Soluble fraction proteins of gastric cancer tissues and paired normal tissues were separated by 2-DE. The differentially expressed proteins were selected and identified by MALDI-TOF-MS and database search. RESULTS: 2-DE profiles with high resolution and reproducibility were obtained. Twenty-three protein spots were excised from sliver staining gel and digested in gel by trypsin, in which fifteen protein spots were identified successfully. Among the identified proteins, there were ten over-expressed and five under-expressed proteins in stomach cancer tissues compared with normal tissues. CONCLUSION: In this study, the well-resolved, reproducible 2-DE patterns of human gastric cancer tissue and paired normal tissue were established and optimized and certain differentially-expressed proteins were identified. The combined use of 2-DE and MS provides an effective approach to screen for potential tumor markers.

Present status and recent advances in living donor liver transplantation for malignant hepatic tumors.

BACKGROUND: Living donor liver transplantation (LDLT) has been increasingly used to treat hepatic tumors worldwide in recent years, and is currently the most effective alternative to deceased donor liver transplantation to overcome the problem of organ shortage. LDLT has played an enormous role in treating early malignant hepatic tumors. But the indication of LDLT for malignant hepatic tumors is based on indefinite criteria. This review summarizes the recent studies in LDLT for treating malignant hepatic tumors. DATA SOURCES: A literature research of the PubMed database was conducted and research articles were reviewed. RESULTS: The current data on LDLT for malignant hepatic tumors, combined with our hospital experience, indicated that if a patient with hepatocellular carcinoma (HCC) who meets with the conventional Milan criteria cannot undergo tumor resection because of poorly preserved liver function, and a cadaveric graft is difficult to obtain within six months, LDLT may be selected. In a patient with recurrence of HCC after conventional therapies, feasibility, optimal timing, and efficacy of LDLT as a second-line treatment should be determined. CONCLUSIONS: Tumor recurrence is related to the biological behavior and staging of the tumor. New immunosuppressors which have anti-tumor effects and inhibit the immune system need to be developed. The indications of LDLT for hepatic malignant tumors should be selected meticulously.

Effect of Sirpalpha1 on the expression of nuclear factor-kappa B in hepatocellular carcinoma.

BACKGROUND: Signal regulatory protein alpha1 (Sirpalpha1) is a member of Sirps families containing four immunoreceptor tyrosine-based inhibitory motifs (ITIMs) domains in the cytoplasm of and an activated substrate of receptor tyrosine kinase (RTK), that negatively regulates the RTK-dependent cell proliferating signal transduction pathway. Previously we found that Sirpalpha1 was closely associated with the occurrence and development of hepatocellular carcinoma (HCC) as well as liver regeneration. Since it is unclear about the regulatory mechanisms, we established the cell line transfected Sirpalpha1 gene and preliminarily clarified the mechanisms by which Sirpalpha1 negatively regulates the carcinogenesis and development of HCC. METHODS: Liver cancer Sk-Hep1 cell was respectively transfected with plasmids of pLXSN, pLXSN-Sirpalpha1 and pLXSN-Sirpalpha1delta4Y2, screened with the drug of G418 (1200 microg/ml), and various transfected Sk-Hep1 cell lines were obtained. The protein expressions of P65, P50, IkappaBalpha, cyclin D1 and Fas in various Sk-Hep1 cell lines were determined by Western blotting, and P65 and P50 were localized by the immunofluorescence technique. RESULTS: Sirpalpha1 could significantly upregulate the protein expression of IkappaBalpha (vs. other cell lines, P<0.05) in the Sk-Hep1 cell, and downregulate the protein expressions of P65, P50 and cyclin D1 (vs. other cell lines, P<0.05) in the Sk-Hep1 cell. P65 protein expression was mainly localized in the cytoplasm in the pLXSN Sk-Hep1 cell, and in the nucleus of the Sk-Hep1 cell with mutant Sirpalpha1delta4Y2, but in nucleus of the Sk-Hep1 cell with wild Sirpalpha1. P50 protein expression was localized in the cytoplasm and nucleus of the pLXSN Sk-Hep1 cell, but in the nucleus of the Sk-Hep1 cell with wild Sirpalpha1 and mutant Sirpalpha1delta4Y2 plasmid. CONCLUSIONS: Sirpalpha1 might negatively regulate and control the abnormal proliferation of liver cancer cells by influencing the protein content and localization of nuclear factor-kappa B, then influence the expression of cyclins such as cyclin D1 in the signal transduction pathway. It may be one of the important mechanisms by which Sirpalpha1 negatively regulates the carcinogenesis and development of HCC.

Negatively regulating mechanism of Sirpalpha1 in hepatocellular carcinoma: an experimental study.

BACKGROUND: Signal regulatory protein (Sirp) is a recently isolated, cloned and identified inhibitor receptor distributed in the membrane of hematopoietic and nonhematopoietic cells. Sirp alpha1 (Sirpalpha1) is a member of Sirp families. Sirpalpha1 can bind SHP-2 in the form of tyrosine phosphorylation by SH2 effect and negatively regulate growth factor, oncogene, or insulin-induced responses as its substrate. This study aimed to preliminarily clarify the negatively regulating proliferation mechanism of Sirpalpha1 in liver cancer. METHODS: pLXSN, Sirpalpha1 and Sirpalpha1P4Y2 plasmids were respectively transfected into Sk-Hep1 liver cancer cell line, and various stable Sk-Hep1 cell lines were obtained with screening agent of G418 (1200 microg/ml). The expressing levels of cyclin D1, CDK4, Fas, beta-catenin and gankyrin in various cell lines were determined with Western blotting. Cell cycles were determined at 0, 12 and 24 hours with flow cytometry after various synchronous cell lines were cultured without serum for 72. Cell apoptosis induced with agent of TNF-alpha (50 ng/ml) was determined with flow cytometry at 0, 0.5, 1, 3, 6 and 12 hours. RESULTS: Sirpalpha1 could significantly decrease the expression of cyclin D1, beta-catenin and gankyrin, but it couldn't affect the expression level of CDK4 and Fas. When synchronous cells were cultured for 12 hours, S phase Sk-Hep1 cell transfected with Sirpalpha1 plasmid was the lowest [(31.92+/-0.22)% vs. other cell lines, P<0.05], and the cell line was highly sensitive to TNF-alpha agent for 1 hour. (59.31+/-0.59)% of apoptotic cells occurred (vs. the other time points, P<0.05). CONCLUSIONS: Sirpalpha1 might block the cell cycle of liver cancer, inhibit cell proliferation, promote cell apoptosis by decreasing the expression of cyclin D1, beta-catenin and gankyrin. It is one of the important mechanisms inhibiting the occurrence and development of hepatocellular carcinoma.

[Comparing the actions of the three flavone ingredients in choerospondias axillaris on arrhythmias induced by aconitine].

OBJECTIVE: To compare the actions of the three flavone ingredients in choerospondias axillaris on arrhythmias Induced by aconitine. METHOD: Langendorff perfuse was applied in the experiment, the antiarrhythmic action was to study by using aconitine on the the isolated heart; The antiarrhythmic action of the three flavone ingredients in choerospondias axillaris was to study by using i.v. aconitine in rat to induce arrhythmias. RESULT: Compared with the NS group, sample 1 and sample 2 both significantly prolonged the beginning time of VF of isolated heart and increased the dosage of aconitine, sample 3 reduced the beginning time of VF of isolated heart and decreased the dosage of aconitine, sample 1 and sample 2 both greatly prolonged the beginning time of VE, VT, VF, HA; sample 3 greatly reduced the beginning time of VT,VF. The actions of the three samples were in a concentration-dependent way. CONCLUSION: Sample 1 and sample 2 both resisted the occurrence of arrhythmias induced by aconitine, sample 3 markedly promoted the occurrence of arrhythmias induced by aconitine.

Effects of signal regulatory proteinalpha1 on proliferation of hepatocellular carcinoma: a preliminary study.

BACKGROUND: Signal regulatory protein alpha1 (Sirpalpha1) is a negative regulatory factor, and inhibits receptor tyrosine kinase-dependent cell proliferating signal. This study was undertaken to observe the effect of signal regulatory proteinalpha1 (Sirpalpha1)on gankyrin,cyclin D1,CDK4 and Fas expression in Sk-hep1 mouse hepatoma carcinoma cell line. METHODS: BOSC 23 packed cells were respectively transfected by means of recombinated retrovirus including pLXSN, pLXSN- Sirpalpha1 and pLXSN- Sirpalpha1P4Y2 with lipofectin, and various plasmid virus media(viral titer 2.1X10(6) CFU/ml) were collected and infected respectively in 80% confluent Sk-hep1 cells. Transfected Sk-hep1 cells were selectively screened with G418 (1200 mug/ml), and Sk-hep1 cell lines transfected with various plasmids were obtained. The protein expressions of gankyrin, cyclin D1, CDK4 and Fas in various Sk-hep1 lines were determined by Western blotting. Various Sk-hep1 lines were recovered to culture with 10% fetal bovine serum at 12 hours and 24 hours after starving culture with free serum for 72 hours, and cells were collected to determine the percentage of S phase cells of proliferating cycle by flow cytometry. RESULTS: Sirpalpha1 transfection remarkably downregulated gankyrin and cyclin D1 expression. Sirpalpha1P4Y2 downregulation of gankyrin expression was greater than that of Sirpalpha1 (P<0.05), but no significant effect of Sirpalpha1 and Sirpalpha1P4Y2 on CDK4 and Fas protein expression was observed in transfected Sk-hep1 lines (P>0.05). The percentage of S phase cells significantly decreased in Sk-hep1 cells transfected with Sirpalpha1 and Sirpalpha1P4Y2 plasmids (vs pLXSN Sk-hep1, P<0.05). The percentage of S phase cells in various Sk-hep1 cells increased when recovering to culture with 10% fetal bovine serum at 12 hours, but the percentage of S phase cells in Sk-hep1 cells transfected with Sirpalpha1 was the lowest (vs pLXSN and Sirpalpha1P4Y2 Sk-hep1, P<0.05). The percentage of S phase cells in transfected pLSXN Sk-hep1 cells was the largest (vs Sirpalpha1 and Sirpalpha1P4Y2 Sk-hep1, P<0.05). There was no significant difference between the transfected Sirpalpha1 Sk-hep1 cells and Sirpalpha1P4Y2 Sk-hep1 cells (P>0.05). CONCLUSIONS: Sirpalpha1 decreases gankyrin and cyclin D1 expression, and inhibits proliferation of liver carcinoma cells. It may be one of the forms for an Sirpalpha1 negative regulation of carcinogenesis and development of hepatocellular carcinoma.

Effects of SIRPalpha1 on liver regeneration after partial hepatectomy in rat.

BACKGROUND: SIRPalpha1 is well known as a negative regulator for cell proliferation through the regulation of the activity of receptor tyrosine kinase with ITAM motif. No investigation to data was undertaken on SIRPalpha1 involving liver regeneration. MATERIALS AND METHODS: Adult male Sprague-Dawley rats underwent approximately 70% partial hepatectomy (PH) or sham operation (SO). Liver specimens were collected at 2, 6, 12, 24, 30, 48, 72, 120, 168, and 240 h after PH or SO. SIRPalpha1 expression was determined in mRNA level by Northern blotting as well as in protein levels via immunohistochemical staining. RESULTS: SO treatment did not induce remarkable changes in SIRPalpha1 expression; however, the level of a 3.9-kb transcript for SIRPalpha1 was significantly up-regulated after PH (versus SO, P < 0.05). SIRPalpha1 mRNA expression in the regenerating liver displayed a biphasic response with its first large peak at as early as 12h followed by a second phase of up-regulation from 48 to 120 h post-PH. SIRPalpha1 mRNA expression returned to its physiological level 168 h later. As seen from immunohistochemistry experiments, SIRPalpha1 protein mainly located in membrane was expressed uniquely in regenerating hepatocytes. Similarly, PH-induced overexpression for SIRPalpha1 protein occurred between 12 and 168 h with a peak level at 24h after surgery. CONCLUSION: SIRPalpha1, a principle negative regulator for cell proliferation, may also play a role in the termination of hepatic proliferation during liver regeneration induced by physiological stress or pathological states, such as PH, drugs, toxins, etc.

Gene and protein expressions of p28GANK in rat with liver regeneration.

AIM: To observe the gene and protein expression changes of p28GANK in regenerating liver tissues, and to reveal the biological function of p28GANK on the regulation of liver regeneration. METHODS: One hundred and thirty two adult male Sprague-Dawley rats were selected, weighing 200-250 g, and divided randomly into sham operation (SO) group and partial hepatectomy (PH) group. Each group had eleven time points: 0, 2, 6, 12, 24, 30, 48, 72, 120, 168 and 240 h, six rats were in each time point. The rats were undergone 70% PH under methoxyflurane anesthesia by resection of the anterior and left lateral lobes of the liver. SO was conducted by laparotomy plus slight mobilization of the liver without resection. Liver specimens were collected at the indicated time points after PH or SO. The expression level of p28GANK mRNA was determined by Northern blot as well as at protein level via immunohistochemical staining. The expressions of p28GANK mRNA in these tissues were analyzed by imaging analysis system of FLA-2000 FUJIFILM and one way analysis of variance. The protein expressions of p28GANK in these tissues were analyzed with Fromowitz' method and Rank sum test. RESULTS: The expression of p28GANK mRNA in the regenerating liver tissues possessed two transcripts, which were 1.5 kb and 1.0 kb. There was a significantly different expression patterns of p28GANK mRNA between SO and PH groups (P<0.01). The expression of p28GANK mRNA increased 2 h after PH, the peak time was 72 h (SO group: 163.83+/-1.4720; PH group: 510.5+/-17.0499, P<0.01). There was a significant difference in the 1.5 kb transcript, which decreased gradually after 72 hours. The protein expression of p28GANK was mainly in the cytoplasm of regenerating hepatocytes, and increased near the central region 24 h after PH, and became strongly positive at 48 h (+++, vs the other time points P<0.05), but decreased 72 h after PH. CONCLUSION: The expression of p28GANK mRNA increases in the early stage of rat liver regeneration, the protein expression of p28GANK is mainly in the cytoplasm of regenerating liver cells. It suggests that the gene of p28GANK may be an important regulatory and controlled factor involved in hepatocyte proliferation during liver regeneration.