Alteration of cyclin D1 in gastric carcinoma and its clinicopathologic significance

AIM: To detect the genetic alteration and abnormal expression of cyclin D1 in gastric carcinoma and investigate its clinicopathologic significance in advanced gastric carcinoma. METHODS: Proteins of cyclin D1 were detected by immunohistochemistry in 42 cases of advanced gastric carcinoma with their follow-up data available, 27 cases of early stage carcinoma, 21 cases of gastric adenoma, 22 cases of hyperplastic polyp and 20 cases of normal mucosa adjacent to adenocarcinomas. Genetic alteration of cyclin D1 was detected by Southern blot and expression of cyclin D1 mRNA was detected by PT-PCR in 42 cases of advanced gastric carcinoma. RESULTS: Cyclin D1 protein was not expressed in normal mucosa, hyperplastic polyp and gastric adenoma, while it was only positively expressed in gastric carcinoma. The expression rate of cyclin D1 protein in early stage gastric carcinoma, advanced gastric carcinoma and lymph node metastasis was 48.1%, 47.4% and 50.0%, respectively. The amplification of cyclin D1 gene was detected in 16.6% of advanced gastric carcinomas. The overexpression of cyclin D1 mRNA was detected in 40.5% of the samples. There was no significant correlation between cyclin D1 protein expression and age, lymph-node metastasis and histological grading in patients with advanced gastric carcinoma (x^2=0.038,0.059,0.241, P>0.05). Significant correlation was observed between the expression of cyclin D1 protein and the 5-year survival rate (x^2=3.92, P<0.05). CONCLUSION: Detection of cyclin D1 protein by immunohistochemistry may be useful in the diagnosis of early gastric carcinomas. Patients with positive expression of cyclin D1 protein tend to have a worse prognosis.

Alterations in expression,proteolysis and intracellular localizations of clusterin in esophageal squamous cell carcinoma

AIM: To investigate biogenesis and intracellular Iocalizations of clusterin to elucidate the potential molecular mechanisms implicated in tumorigenesis of esophageal mucosa.METHODS: Semi-quantitative RT-PCR for multi-region alteration analysis, Western blot for different transcriptional forms and immunohistochemical staining for intracellular Iocalizations of clusterin were carried out in both tissues and cell lines of ESCC.RESULTS: The N-terminal deletions of the clusterin gene and the appearance of a 50-53 ku nuclear clusterin, an uncleaved, nonglycosylated, and disulfide-linked isoform,were the major alterations in cancer cells of esophagus.Naturally the 40 ku clusterin was located in the connective tissue of the lamina propria of epithelial mucosa and right under the basal membrane of epithelia, but it was disappeared in stromal mucosa of esophagus and the pre-matured clusterin was found positive in cancerous epithelia.CONCLUSION: The N-terminal deletion of clusterin may be essential for its alterations of biogenesis in ESCC.

Propofol vs midazolam plus fentanyl for upper gastrointestinal endomicroscopy:A randomized trial

AIM:To compare the endomicroscopic image quality of integrated confocal laser endomicroscopy(iCLE)and sedation efficacy of propofolvs midazolam plus fentanyl(M/F).METHODS:Consecutive outpatients undergoing iCLE were prospectively recruited and randomized to the propofol group(P group)or M/F group.The patient,performing endoscopist and endoscopic assistant were blinded to the randomization.The quality of endomicro-scopic images and anesthetic efficacy outcomes were blindly evaluated after iCLE examination.RESULTS:There were significantly more good quality endomicroscopic images in the propofol group than in the M/F group(72.75%vs 52.89%,P<0.001).The diagnostic accuracy for upper gastrointestinal mucosal lesions using confocal laser endomicroscopy favors the P group,although this did not reach statistical significance.Adverse events and patient assessment were not significantly different for M/F vs propofol except for more frequent intraprocedural recall with M/F.Procedure duration and sedation times were significantly longer in the M/F group,while the scores of endoscopist,anesthetist and assistant assessment were all significantly better in the P group.CONCLUSION:Sedation with propofol might increase the proportion of good quality endomicroscopic images,and may result in improved procedural efficacy and diagnostic accuracy during iCLE examination.

Effect of diabetes and insulin treatment on nitric oxide synthase content in rat corpus cavemosum

Aim: To study the effect of diabetes mellitus and insulin treatment on rat penile nitric oxide synthase content.Methods: Male Wistar rats were divided at random into two groups: the Control (n = 8) and the Diabetic (n =17). Diabetes mellitus was induced by intraperitoneal injection of streptozotocin. The diabetic animals were then ran-domly divided into two subgroups; diabetic rats without insulin treatment (n = 7) and diabetic rats with insulin treat-ment (n = 10). The neuronal nitric oxide synthase (nNOS) in the penile corpus cavernosum were assayed by immumo-histochemical staining with specific antibody to nNOS and the nNOS-positive nerve fibers were counted semiquantita-tively under a high power microscope. Results: The nNOS- positive nerve fibres in diabetic rats with treatment washigher than that in diabetic rats without treatment ( P < 0.05) and lower than that in the controls ( P < 0.01). ThenNOS-positive nerve fibres in diabetic rat without treatment were also lower than that in the controls ( P < 0.01). Con-clusion; In streptozotocin-induced diabetic rats, the nNOS content in the penile corpus cavernosum was significantlydecreased. Insulin treatment at the dose level employed partially restores the penile nNOS content in these rats.

In vitro study of the influence of GST-π gene transfer on drug-resistance of human cord blood CD34^+ cells

Objective:To investigate the influence of GST-π gene transfer on drug-resistance of human cord blood CD34 + cells.Methods:CD34 + cells were purified from cord blood from normal full-term pregnancy.Gene transduction into human cord blood CD34 + cells was carried out using GST-π gene containing retrovirus vector.The GST-π gene expression in transduced CD34 + cell was confirmed by RT-PCR.After confirmation of GST-π gene transfer,the transfected CD34 + cells were cultured by colony assay in the presence of carboplatin.Results:GST-π mRNA was detected in 30% of CFU-GM derived from GST-π gene transduced CD34 + cells.In vitro drug resistance test showed that the number of CFU-GM formed was significantly higher (2～3 fold) in GST-π gene transduced CD34 + cells than untransduced CD34 +cells.Conclusion:GST-π gene transfer can confer resistance to hematopoietic progenitors against carboplatin in vitro.

Assessment of hepatic VX_2 tumors with combined percutaneous transhepatic lymphosonography and contrast-enhanced ultrasonographic imaging

AIM： To evaluate the feasibility and efficacy of percutaneous transhepatic lymphosonography （PTL） as a novel method for the detection of tumor lymphangiogenesis in hepatic VX2 of rabbits and to evaluate combined PTL and routine contrast-enhanced ultrasonographic imaging for the diagnosis of liver cancer. METHODS： Ten rabbits with VX2 tumor were included in this study. SonoVue （0.1 mL/kg） was injected into each rabbit via an ear vein for contrast-enhanced ultrasonographic imaging, and 0.5 mL SonoVue was injected into the normal liver parenchyma near the VX2 tumor for PTL. Images and/or movie clips were stored for further analysis. RESULTS： UItrasonographic imaging showed VX2 tumors ranging 5-19 mm in the liver of rabbits. The VX2 tumor was hyperechoic and hypoechoic to liver parenchyma at the early and later phase, respectively. The hepatic lymph vessels were visualized immediately after injection of contrast medium and continuously vi- sualized with SonoVue during PTL. The boundaries of VX2 tumors were hyperechoic to liver parenchyma and the tumors. There was a significant difference in the values for the boundaries of VX2 tumors after injection compared with the liver normal parenchyma and the tumor parenchyma during PTL.CONCLUSION： PTL is a novel method for the detection of tumor lymphangiogenesis in hepatic VX2 of rabbits. Combined PTL and contrast-enhanced ultrasonographic imaging can improve the diagnosis of liver cancer.

PROGNOSTIC FACTORS FOR DEEP SITUATED MALIGNANT GLIOMAS TREATED WITH LINAC RADIOSURGERY

Objective To study the function of radiosurgery on malignant glioma by analyzing prognostic factors affecting malignant gliomas treated with linac radiosurgery. Method Fifty-eight patients with deep situated malignant gliomas, aged 7 to 70 years, 28 anaplastic astrocytomas and 30 glioblastomas multiforme were analyzed. The median volume of tumor was 10.67 cm3, and median prescription dose for linac radiosurgery was 20 Gy. Results were analyzed with Kaplan-Meier curve and Cox regression. Result In follow-up 44.8 percent tumors (26 patients) decreased in size. Median tumor local control interval was 10 months, 15 months for anaplastic astrocytomas, and 9 months for glioblastoma multiforme. Tumor local control probability was 37.9 percent for 1 year and 10.3 percent for 2 years. Median survival was 22.5 months for anaplastic astrocytoma, 13 months for glioblastoma multiforme, and 15 months for all patients. The survival probability was 79.3 percent at 1 year and 20.6 per-cent at 2 years. Isocenter numbers and tumor volume were the prognostic factors for tumor control, but conformity index was the prognostic factor for survival by Cox regression analysis. Considering pathology, only isocenter number and target volume significantly affected tumor control interval. Complications appeared in 44.8 percent patients and the median interval of com-plication onset was 8 months. Symptomatic cerebral edema was observed in 31.0 percent patients. Conclusion Linac radiosurgery can effectively improve tumor local control and prolong survival for deep situated mali-gnant gliomas.

Effect of NS-398 on colon cancer cells

AIM: To study the effect of NS-398, a selective cydooxygenase 2 (COX-2) inhibitor, on invasion of colon cancer cell line HT-29 in vitro and to explore its mechanisms. METHODS: Invasive behaviors of the malignant colon cancer cell line HT-29 were investigated in this study. Expressions of COX-2 and CD44v6 in HT-29 cells were detected by flow cytometry. Cellular survival rate was determined by MTT assay. The invasive capacity was quantified by a modified Boyden chamber model. Alterations of cytoskeleton component F-actin were observed by confocal laser scanning microscope. RESULTS: Flow cytometry analysis showed that COX-2 was highly expressed in HT-29 cells. The invasive capability of HT-29 cells could be greatly inhibited by NS-398 at the experimental concentrations of 0.1,1.0 and 10 μmol/L with an inhibitory rate of 22.74%, 42.35% and 58.61% (P<0.01), respectively. MTT assay showed that NS-398 at the experimental concentrations had no significant influence on cellular viability, indicating that such anti-invasive effects had no relationship with cytotoxicity. F-actin was mainly distributed around nuclei forming annular structure in HT-29 cells. After exposure to NS-398 of 10 μmol/L, the annular structure around nuclei disappeared and the fluorescence intensity of F-actin decreased obviously. Treatment with NS-398 could down-regulate the expression of CD44v6 as well. CONCLUSION: NS-398 has anti-invasive effects on colon cancer HT-29 cells in vitro, which may be mediated by a novel mechanism of disruption of cytoskeleton. Down-regulation of CD44v6 expression may be related to alterations of cytoskeleton.

The clinical significance of the expression of the metastasis suppressor gene KAI1 in epithelial ovarian carcinoma

Objective:To investigate the potential role of KAI1 in epithelial ovarian carcinoma(EOC), and to determine whether the expression of the KAI1 gene is associated with EOC progression.The clinical significance in this tumor is also evaluated.Method: Immunohistochemistry SP method was performed to examine the expression level of KAI1 in EOC.Results: Thirty eight of 66 cancer specimens showed KAI1 protein positive (57.58%),which lower significantly than that in the patients with benign and borderline tumors(90.91%).The statistical evaluation showed that the expression of KAI1 had a correlation with FIGO stags as well as lymph node metastasis(or distant metastasis)(P<0.05).It also revealed an inverse relationship between histological grade and KAI1 expression (P<0.05).Conclusion: KAI1 protein expression is closely correlated with the malignent progression and metastasis of EOC; detecting the expression of KAI1 probably possesses clinical significance in evaluating the differentiation,tumor progression and predicting the prognosis of EOC.

The invivo study of myeloprotection by GST-π gene transfected human cord blood hematopoietic stem cells transplantation

Objective :To investigate the influence of GST πgenetransferintohumancord blood hematopoie ticstem cellson their drugres is tanceagains tanti tumordrugs invivo .Methods: GST πgenetran sfectionin to human cord blood CD 34+cells was carried outusing are trovirusvec torPLJ GST πwith the aido f fibronect in .Succes sfulgenetransfer was confirmed by invitrocolony assay and RT PCR .GST πgenetrans duced human cord blood CD34+cells were the nengrafted in to 4 week old total body irradiated NOD/Scid mice and carboplatin was intraperitoneally admin is tered sequentially at 4 weeks interval 4 week saftereng raftment.Results :Peripheral blood (PB) WBC was significantly higher in GST πmice than control mice after 2 course of car boplat in .Retroviral GST π expression in bone marrow hematopoietic progenitor cells of recipient mice was detected by RT PCR 16 weeks after Xenotransplantation .Conclusion :The transfection of GST π gene could confer ,to some extent ,resistance to cord blood stem cells against carboplatin in vivo .

Study of cellular immunity response of mB7-1 gene transfected mouse ovarian cancer cell line and its tumorigenecities in vivo

Objective:To investigate the cellular immunity response in vitro and the tumorigenecities in vivo of mB7 1 gene transfected murine ovarian cancer cell line.Methods:mB7 1 gene was transfected into the NuTu 19 cell line by retrovirus vector, and the expression of mB7 1 gene was confirmed by flow cytometry(FCM).NuTu 19/neo and NuTu 19/mB7 1 cells were injected subcutaneously into syngeneic Fischer 344 rats respectively,and their tumorigenecities were recorded.Proliferation indices of lymphocyte were assayed after syngenieic mixed tumor lymphocyte cultures(MTLCs).The lysis activity of CTL toward tumor cells was determined using methyl thiazolyl tetrazolium(MTT) assay.Results:Successful transfection of mB7 1 gene into NuTu 19 cell line was comfirmed with FCM.In vitro study showed that there was no obvious changes in cell growth of gene transfected cell line,compared with the cell line NuTu 19.NuTu 19/mB7 1 cells could induce more effective proliferation of effector lymphocytes(P<0.05). The lysis activity of CTL activated by NuTu 19/mB7 1 was stronger than that of NuTu 19/neo (P<0.01).Tumor sizes were smaller in the NuTu 19/mB7 1 receptance syngeneic Fischer 344 rats compared with those in the control group.Conclusion:mB7 1 genetically modified ovarian cancer cells could induce the cellular immunity response in vitro and the tumorigenecitiy of NuTu 19 cells was decreased after inoculation with the experimental vaccine.

The effect of interleukin-6 gene transfer on human cord blood megaka ryopoiesis

Objective:To investigate the effect of IL-6 gene transfe r into human cord blood hematopoietic stem cells on the production of megakaryocy t ic progenitors.Methods:IL-6 gene was transfected into human c o rd blood CD34+ cells using a retrovirus vector with the aid of recombinant fibro nectin fragments in the presence of a cocktail of cytokines (SCF,IL-6,sIL-6R,F L,and TPO).Colony-forming units-megakaryocyte (CFU-MK) assays were performed as IL-6 gene transduced CD34+ cells were incubated alone or in combination with I L -3 or sIL-6R, controlled with neoR gene transduced CD34+ cells.Result s :IL-6 alone or sIL-6R alone stimulated few CFU-MK colonies,the addit ion of sIL-6R to IL-6 gene transduced CD34+ cells significantly enhanced the prod uction of CFU-MK colonies.IL-6 gene transduced CD34+ cells showed a modest syn er gistic effect with IL-3.Conclusion:These results suggest that IL-6 gene transfer may protect patients from chemotherapy-induced thrombocytop en ia.

Surgical Management of Supraglottic Laryngeal Carcinoma in Patients with Special Emphasis on Functional Preservation

OBJECTIVE To explore the surgical methods and evaluate the long-term results of laryngectomy in patients with supraglottic laryngeal cancer.METHODS A total of 182 patients with supraglottic laryngeal carcinoma underwent an operation from 1979 to 1999. These cases comprised 11 in stage Ⅰ , 45 in stage Ⅱ , 49 in stage Ⅲ and 77 in stage Ⅳ. The choice of surgical procedure was decided based on the condition of the diseasedl arynx. The surgical procedures proposed by TD Wang were adhered to as follows: minor partial laryngectomy 36, major partial laryngectomy 85,subtotal partial laryngectomy with laryngoplasty 22 and total larygectomy 39.RESULTS The final rate of larynx preservation was 78.6% (143/182) and 69.8% (88/126) in patients with stage III and IV diseases. The extubation rate was 81.8% in cases with preservation of laryngeal function. The overall 3-and 5-year survival rates were 82.9% and 67.3%, with 76.88% and 57.4% in the advanced (stage III and IV) cases who survived with preserved laryngeal function, and 82.5% and 67.0% in similar advanced cases who were treated by total laryngectomy. The difference in the survival rates between these 2 groups was not statistically significant.CONCLUSION It is suggested that preservation of the laryngeal function is possible for advanced supraglottic laryngeal carcinoma without compromising the long-term survival rate. To improve the rate of larynx preservation, one should follow the surgical methods suggested.

Features of animal models of complex partial epilepsy established through unilateral,bilateral and alternate-side kindling at hippocampus of rats

BACKGROUND： Electrical stimulation kindling model, having epilepsy-inducing and spontaneous seizure and other advantages, is a very ideal experimental animal model. But the kindling effect might be different at different sites. OBJECTIVE： To compare the features of animal models of complex partial epilepsy established through unilateral, bilateral and alternate-side kindling at hippocampus and successful rate of modeling among these 3 different ways. DESIGN： A randomized and controlled animal experiment SETTING： Department of Neurology, Qilu Hospital, Shandong University MATERIALS： Totally 60 healthy adult Wistar rats, weighing 200 to 300 g, of either gender, were used in this experiment. BL-410 biological functional experimental system （Taimeng Science and Technology Co. Ltd, Chengdu） and SE-7102 type electronic stimulator （Guangdian Company, Japan） were used in the experiment. METHODS： This experiment was carried out in the Experimental Animal Center of Shandong University from April to June 2004. After rats were anesthetized, electrode was implanted into the hippocampus. From the first day of measurement of afterdischarge threshold value, rats were given two-square-wave suprathreshold stimulation once per day with 400 μA intensity, 1ms wave length, 60 Hz frequency for 1 s duration. Left hippocampus was stimulated in unilateral kindling group, bilateral hippocampi were stimulated in bilateral kindling group, and left and right hippocampi were stimulated alternately every day in the alternate-side kindling group. Seizure intensity was scored： grade 0： normal, 1： wet dog-like shivering, facial spasm, such as, winking, touching the beard, rhythmic chewing and so on; 2： rhythmic nodding; 3： forelimb spasm;4： standing accompanied by bilateral forelimb spasm;5： tumbling, losing balance, four limbs spasm. Modeling was successful when seizure intensity reached grade 5. t test was used for the comparison of mean value between two samples. MAIN OUTCOME MEASURES： Comparison of the successful rate of modeling, the times of stimulation to reach intensity of grade 5, the lasting time of seizure of grade 3 of rats in each group. RESULTS： Four rats of alternate-side kindling group dropped out due to infection-induced electrode loss, and 56 rats were involved in the result analysis. The successful rate of unilateral kindling group, bilateral kin- dling group and alternate-side kindling group was 55%（11/20）,100%（16/16）and 100%（20/20）, respective- ly. The stimuli to reach the grade 5 spasm were significantly more in the bilateral kindling group than in the unilateral kindling group [（30.63±3.48）, （19.36±3.47）times, t=8.268, P 〈 0.01], and those were significantly fewer in the alternate-side kindling group than in the unilateral kindling group [（ 10.85±1.98）times, t=-8.744, P 〈 0.01]. The duration of grade 3 spasm was significantly longer in the bilateral kindling group than in the unilateral kindling group [（9.75±2.59）, （3.21 ±1.58）days,t=-8.183,P 〈 0.01], Among 20 successful rats of al- ternate-side kindling group, grade 5 spasm was found in the left hippocampi of 11 rats, but grade 3 spasm in their right hippocampi; Grade 5 spasm was found in the right hippocampi of the other 9 rats, grade 4 spasm in the left hippocampus of 1 rat and grade 3 of 8 rats. CONCLUSION ： The speed of establishing epilepsy seizure model by alternate-side kindling is faster than that by unilateral kindling, while that by bilateral kindling is slower than that by unilateral kindling. The successful rate is very high to establish complex partial epilepsy with alternate-side or bilateral kindling. Epilepsy seizure established by alternate-side kindling has antagonistic effect of kindling and the seizure duration of grade 3 spasm is prolonged.

Matrix metalloproteinases-2,-9 and tissue inhibitor of metallo-proteinase-1 in lung cancer invasion and metastasis

Lung cancer is a major cause of death from malignant disease due to its high incidence, malignant behavior and lack of major advancements in treatment strategies. The ability to invade tissues and establish colonies at remote sites is a defining characteristic of malignant neoplasms. Matrix metalloproteinases ( MMPs) are zinc proteinases that degrade compounds of extracellular matrix (ECM). These enzymes have been implicated in tumour invasion and metastasis through degrading many extracellular matrix proteins especially MMP-2 and MMP-9, which are regarded as markers of tumour invasion and metastasis.(1) The purpose of this study is to examine the role of MMP-9, MMP-2, tissue inhibitor of metalloproteinase-1 (TIMP-1) and MMP-9/TIMP-1 in tumour invasion and metastasis as well as the relationships between the mRNA expression of MMP-9 in white blood cells and MMP-9 levels in the plasma.

Efficacy and safety of vitamin D3 in patients with diabetic nephropathy： a meta-analysis of randomized controlled trials

Background Several studies found that vitamin D3 might alter glucose metabolism,protect kidney from injury and even proposed the mechanisms.But results from previous studies have been conflicting.The aim of this study was to evaluate the efficacy and safety of vitamin D3 in patients with diabetic nephropathy.The underlying mechanism of vitamin D3 decreasing proteinuria is also discussed.Methods We conducted a search of English and Chinese articles using database of Pubmed,Embase,Sinomed,CNKI,Wanfang and clinical trial register centers,for randomized controlled trials of vitamin D3 in diabetic nephropathy patients.Two reviewers performed independently.Meta-analysis was used when studies were homogeneous enough.Results Twenty studies,including 1 497 patients with diabetic nephropathy,were involved in this systemic review.Vitamin D3-treated patients with diabetic nephropathy had a statistically significant reduction in 24-hour proteinuria （weighted mean difference-0.44,95% CI-0.54 to-0.34,Z=8.80,P 〈0.000 01） and urine albumin/creatine ratio （standardized mean difference-0.29,95% CI-0.48 to-0.10,Z=2.96,P=0.003）.But vitamin D3 supplementation did not significantly reduce blood pressure and hemoglobin A1c compared with control group.The potential mechanisms about the renal protection of vitamin D3,including the inhibition of rennin-angiotensin system,the protection of kidney from inflammation,fibrosis and the structure change of kidney are discussed.In addition,vitamin D3 did not significantly increase the incidence of adverse effects,including total adverse effects,gastrointestinal adverse effects and fluctuation of blood pressure.Conclusions Vitamin D3 can ameliorate proteinuria and protect kidney from injury in patients with diabetic nephropathy.This renoprotective effect is independent of blood pressure and glucose reduction.And it does not increase any adverse effects than control,even in combination therapy with angiotensin converting enzyme inhibitors/angiotensin receptor blockers.But due to the limited randomized controlled trials of high quality,more clinical researches should be taken in the future.

A high-fat diet reverses improvement in glucose tolerance induced by duodenal-jejunal bypass in type 2 diabetic rats

Background Bariatric surgery offers successful resolution of type 2 diabetes mellitus （T2DM）. However, recurrence of T2DM has been observed in a number of patients with initial resolution after bariatric surgery. This study aimed to induce reversal of the improvement of diabetes in T2DM rats after duodenal-jejunal bypass （DJB）, and identify the effects of weight changes and gut hormones that might be involved.

Relations of nuclear factor-kappa B activity in the kidney of children with primary nephrotic syndrome to clinical manifestations, pathological types, and urinary protein excretion

The pathogenesis of childhood primary nephrotic syndrome (PNS) is unclear. However, an immune mechanism has generally been accepted as a cause. Imbalance of T lymphocyte and a variety of inflammatory cytokines, chemotactic and transcription factors are involved in the pathophysiology and manifestations of PNS,^(1,2) (and nuclear) factor kappa B (NF-κB) transcriptionally regulates the expression of these factors.~3 Research has been focused on NF-κB and inflammatory regulated mediators of renal diseases, but seldom on different clinical manifestations and histopathological changes. In order to explore a potential mechanism for the pathogenesis of PNS in children and a basis for preventing its advance, we determined NF-κB activity in the kidney of children with PNS in vitro using immunohistochemical staining and the multimedia coloured pathological image analysis system and its relations to clinical manifestations, histopathological changes and 24-hour urinary protein excretion.

Effect of chemical treatment of silicon gel on tissue compatibility

Background Silicon gel is unfavourable for cell attachment and growth. This study was to study if pretreating the surface of silicon gel with chemical agents affects the proliferation of epithelial cells Methods Silicon gel was made and treated with either mixed acid solution (containing 232 g/dm 3 of H 2SO 4 and 8 g/dm 3 of K 2Cr 2O 7) or 300 cm 3/dm 3 peroxide for 5, 10, and 15 minutes or 10, 15, and 20 minutes, respectively The cultured corneal epithelial cells were seeded onto those silicon gels and kept for 13 days Immunohistochemical investigations were then carried out for integrin (alpha 6 or beta 4) and actin KH*2/5DResults Growth of the epithelial cells in silicon gels treated with mixed acid solution for 10 minutes and 15 minutes was much significant than that in the untreated gels After a 12-hour culture, a small number of corneal epithelial cells were proliferated on the surface of the silicon gels that had been treated with peroxide for 15 minutes After a 3-day culture, those cells were further proliferated and fused together The corneal epithelial cells did not grow well in the silicon gels treated with peroxide for 10 or 20 minutes Immunostaining revealed the expression of actin and integrin alpha 6 or beta 4 on the silicon gels that were treated with mixed acid solution for 10 minutes or peroxide for 15 minutes Conclusion Silicon gels treated either with mixed acid solution for 10 or 15 minutes or with peroxide for 15 minutes improves cell proliferation