AIM:To study the effects of rhubarb (dried root of Rheum officinale Baill.) on contractile activity of isolated gastric muscle strips of guinea pigs and its possible mechanism. METHODS: A total of 48 guinea pigs were ...AIM:To study the effects of rhubarb (dried root of Rheum officinale Baill.) on contractile activity of isolated gastric muscle strips of guinea pigs and its possible mechanism. METHODS: A total of 48 guinea pigs were killed to remove the whole stomach. Then, the stomach was opened and the mucosal layer was removed. Parallel to the circular fibers, muscle strips were cut from the body. Each isolated gastric muscle strip was suspended in a tissue chamber containing 5 mL Krebs solution, constantly warmed by water jacket at 37℃ and bubbled continuously with a mixed gas of 950 mL/L O2 and 50 mL/L CO2. After being incubated for 1 h with 1 g tension, rhubarb of varied concentrations (1%, 2%, 7%, 20% and 70%) was added cumulatively into the tissue chamber at intervals of 2 min. Atropine (10-6 mol/L) or isoptin (5x10-8 mol/L) or hexamethonium (10-5 mol/L) was given 2 min before the administration of rhubarb. The isometrical response was measured with an ink-writing recorder. RESULTS: Rhubarb dose dependently increased the resting tension of gastric body circular muscle (CM) (r = 0.726, P<0.05). Atropine (r= 0.829, A:0.05), isoptin (r= 0.764, A;0.05) and hexamethonium (r = 0.797, P<0.05) did not affect its action in a dose-related manner. Atropine apparently reduced the increasing action of 1%, 3%, 10%, 30% and 100% rhubarb on the resting tension of gastric body CM. Isoptin inhibited the effect of 10%, 30% and 100% rhubarb on the resting tension of gastric body CM. Hexamethonium reduced the increasing action of 1%, 10%, 30% and 100% rhubarb on the resting tension of gastric body CM. Rhubarb increased the contractile frequency of CM of body. While atropine, isoptin and hexamethonium did not inhibit the contractile frequency of gastric body CM in comparison with rhubarb at the same concentration, rhubarb at the highest concentration (100%) decreased the mean contractile amplitude of gastric body CM. Atropine, isoptin and hexamethonium did not affect the mean contractile amplitude of gastric body CM compared to rhubarb at the same concentration. CONCLUSION: Rhubarb has exciting actions on isolated gastric smooth muscle strips of guinea pig. The exciting action of rhubarb is partly mediated via cholinergic M receptor, cholinergic N receptor and L-type calcium channel.展开更多
Regenerating gene (Reg or REG) family, within the superfamily of C-type lectin, is mainly involved in the liver,pancreatic, gastric and intestinal cell proliferation or differentiation. Considerable attention has focu...Regenerating gene (Reg or REG) family, within the superfamily of C-type lectin, is mainly involved in the liver,pancreatic, gastric and intestinal cell proliferation or differentiation. Considerable attention has focused on Reg family and its structurally related molecules. Over the last 15 years, 17 members of the Reg family have been cloned and sequenced. They have been considered as members of a conserved protein family sharing structural and some functional properties being involved in injury, inflammation,diabetes and carcinogenesis. We previously identified Reg Ⅳ as a strong candidate for a gene that was highly expressed in colorectal adenoma when compared to normal mucosa based on suppression subtractive hybridization (SSH),reverse Northern blot, semi-quantitative reverse transcriptase PCR (RT-PCR)and Northern blot. In situ hybridization results further support that overexpression of Reg Ⅳ may be an early event in colorectal carcinogenesis. We suggest that detection of Reg Ⅳ overexpression might be useful in the early diagnosis of carcinomatous transformation of adenoma.This review summarizes the roles of Reg family in diseases in the literature as well as our recent results of Reg Ⅳ in colorectal cancer. The biological properties of Reg family and its possible roles in human diseases are discussed. We particularly focus on the roles of Reg family as sensitive reactants of tissue injury, prognostic indicators of tumor survival and early biomarkers of carcinogenesis. In addition to our current understanding of Reg gene functions, we postulate that there might be relationships between Reg family and microsatellite instability, apoptosis and cancer with a poor prognosis. Investigation of the correlation between tumor Reg expression and survival rate, and analysis of the Reg gene status in human maliganancies, are required to elucidate the biologic consequences of Reg gene expression, the implications for Reg gene regulation of cell growth, tumorigenesis, and the progression of cancer. It needs to be further attested whether Reg gene family is applicable in early detection of cancer and whether Reg and Reg-related molecules can offer novel molecular targets for anticancer therapeutics. This has implications with regard to prognosis, such as in monitoring cancer initiation,progression and recurrence, as well as the design of chemotherapeutic drugs.展开更多
AIM: To study the effects of phosphorus-32 glass microspheres(^32P-GMS) on human hepatocellular carcinoma in nude mice. METHODS: Human liver cancer cell line was implanted into the dorsal subcutaneous tissue of 40 BAL...AIM: To study the effects of phosphorus-32 glass microspheres(^32P-GMS) on human hepatocellular carcinoma in nude mice. METHODS: Human liver cancer cell line was implanted into the dorsal subcutaneous tissue of 40 BALB/c nude mice. Then the 40 tumor-bearing BALB/c nude mice were allocated into treatment group (n=32) and control group (n=8). In the former group different doses of ^32P-GMS were injected into the tumor mass, while in the latter nonradioactive ^31P-GMS was injected into the tumor mass. The experimental animals were sacrificed on the 14th day. The ultrastructural changes of tumor in both treatment group and control group were studied with transmission electron microscopy (TEM) and stereology. RESULTS: In treatment group, a lot of tumor cells were killed and the death rate of tumor cells was much higher (35-70%). UItrastructurally, severe nuclear damage was observed in the death cells. The characteristics of appoptosis such as margination of heterochromatin was also found in some tumor cells. Besides, well differentiated tumor cells, degenerative tumor cells and some lymphocytes were seen. The skin and musde adjacent to the tumor were normal. In control group, the tumor consisted of poorly differentiated tumor cells, in which there were only a few of dead cells (5%). Stereologicl analysis of ultrastructral morphology showed that Vv of nuclei (53.31±3.46) and Vv of nucleoli (20.40±1.84) in the control group were larger than those (30.21±3.52 and 10.96±2.52) in the treatment group respectively (P<0.01), and Vv of RER (3.21±0.54) and Vv of mitochondria (4.53±0.89) in the control group were smaller than those (8.67±1.25 and 7.12±0.95) in the treatment group respectively (P<0.01, 0.05). Sv of the membrane of microvilli and canaliculi (27.12 um^2/100 um^3±11.84 um^2/100 um^3) in the control group was smaller than that (78.81 um^2/100 um^3±19.69 um^2/100 um^3) in the treatment group (P<0.01). But Vv of lipid particles (3.71±1.97) and Vv of vacuoles (5.72±1.58)were much larger than those (0.30±0.16 and 0.35±0.15) in the treatment group respectively (P<0.05, P<0.01). CONCLUSION: The experimental results indicate that local administration of ^32P-GMS can produce obvious effect on liver cancer cells and the anticancer effect of ^32P-GMS is directly proportional to the dose administrated. UItrastructural stereology can also show the effect of ^32P-GMS on the normalization of tumor cells, which is beneficial to the prognosis and treatment of patients. Moreover, local administrtion of ^32P-GMS is also safe.展开更多
AIM: To analyze the structure and expressions of the protein encoded by an HCC-associated novel gene, lysosomeassociated protein transmembrane 4 β (LAPTM4B). METHODS: Primary structure and fundamental characteristics...AIM: To analyze the structure and expressions of the protein encoded by an HCC-associated novel gene, lysosomeassociated protein transmembrane 4 β (LAPTM4B). METHODS: Primary structure and fundamental characteristics of LAPTM4B protein were analysed with bioinformatics. Expressions of LAPTM4B in HCC tissues and various cell lines were detected using polyclonal antibodies and Western blot. RESULTS: LAPTM4B encoded two isoforms of proteins with molecular masses 35-ku and 24-ku, respectively. The expression level of LAPTM4B-35 protein in HCC tissues was dramatically upregulated and related to the differentiation status of HCC tissues, and it was also high in some cancer cell lines. Computer analysis showed LAPTM4B was an integral membrane protein with four transmembrane domains. LAPTM4B showed relatively high homology to LAPTM4A and LAPTM5 in various species. CONCLUSION: LAPTM4B gene encoded two isoforms of tetratansmembrane proteins, LAPTM4B-35 and LAPTM4B-24. The expression of LAPTM4B-35 protein is upregulated and associated with poor differentiation in human HCC tissues, and also at high levels in some cancer cell lines. LAPTM4B is an original and conserved protein.展开更多
AIM: To investigate the effect of interleukin-12 p40 gene (IL12E 3'-untranslated region polymorphism on the outcome of HCV infection.METHODS: A total of 133 patients who had been infected with HCV for 12-25 (18.2...AIM: To investigate the effect of interleukin-12 p40 gene (IL12E 3'-untranslated region polymorphism on the outcome of HCV infection.METHODS: A total of 133 patients who had been infected with HCV for 12-25 (18.2±3.8) years, were enrolled in this study. Liver biochemical tests were performed with an automated analyzer and HCV RNA was detected by fluorogenic quantitative polymerase chain reaction. B-mode ultrasound was used for liver examination. Polymerase chain reactionrestriction fragment length polymorphism (PCR-RFLP) was used for the detection of IL12B (1188A/C) polymorphism.RESULTS: Self-limited infection was associated with AC genotype (OR = 3.48; P = 0.001) and persistent infection was associated with AA genotype (OR = 0.34; P = 0.014)at site 1188 of IL12B. In patients with persistent HCV infection, no significant differences were found regarding the age, gender, duration of infection and biochemical characteristics (P>0.05). According to B-mode ultrasound imaging and clinical diagnosis, patients with persistent infection were divided into groups based on the severity of infection. No significant differences were found in the frequency of IL-12 genotype (1188A/C) between different groups (P>0.05).CONCLUSION: The polymorphism of II12B (1188A/C)appears to have some influence on the outcome of HCV infection.展开更多
AM: To produce high-quality potyclonal antibody to lysosomeassociated protein transmembrane 4B-35 and to identify LAPTM4B-35 expression in cancer tissues and its correlation with differentiation status of hepatocellul...AM: To produce high-quality potyclonal antibody to lysosomeassociated protein transmembrane 4B-35 and to identify LAPTM4B-35 expression in cancer tissues and its correlation with differentiation status of hepatocellular carcinoma (HCC). METHODS: The 297 bp 5' end of LAPTM4BcDNA was obtained by PCR and inserted into prokaryotic expression vector pGEX-KG. Then the recombinant pGEX-KG-N_(1-99) was transformed into E. coli JM109 to express GST-fusion protein. The fusion protein was purified by glutathione sepharose^(TM) 4B agarose. The purified GST-LAPTM4B-N_(1-99) was characterized by SDSPAGE, and used to immunize rabbits. The titer and specificity of antisera were detected by ELISA and Western blot, respectively. The correlation between the expression levels of LAPTM4B-35 and the differentiation status of HCC was analyzed via Western blot. The expression of LAPTM4B-35 in HCC and other six cancer tissues was investigated via tissue chip and immunohistochemical analysis. RESULTS: About 6.2 mg of pure GST-LAPTM4B-N_(1-99) was isolated from 1 L of bacteria. The GST-LAPTM4B-N_(1-99) produced high titer antisera in rabbits and showed good immunity. Western blot showed specific reactions for the antibody to the LAPTM4B-35 in the total proteins from HCC tissues and BEL-7402 cells, also to the fusion protein purified or in the transformed bacteria. LAPTM4B-35 was remarkably expressed in several cancers, such as HCC, breast cancer, gastric carcinoma, lung cancer, and colon carcinoma, but not commonly expressed in esophageal cancer and rectum carcinoma. Notably, the expression levels of LAPTM4B-35 were significantly and inversely correlated to the differentiation of HCCs in a 20 case analysis. CONCLUSION: Specific polyclonal antibody (LAPTM4BN_(1-99)-pAb) to LAPTM4B-35 was produced. It identified the expression of LAPTM4B-35 in some cancer tissues originated from single layer cuboidal and columnar epithelial cells and firmly demonstrated that the expression of LAPTM4B-35 in HCC was inversely correlated with the differentiation of HCC.展开更多
AIM:To compare the expression patterns of cholecystokinin-B (CCK-B)/gastrin receptor genes in matched human gastric carcinoma and adjacent non-neoplastic mucosa of patients with gastric cancer,inflammatory gastric muc...AIM:To compare the expression patterns of cholecystokinin-B (CCK-B)/gastrin receptor genes in matched human gastric carcinoma and adjacent non-neoplastic mucosa of patients with gastric cancer,inflammatory gastric mucosa from patients with gastritis,normal stomachs from 2 autopsied patients and a gastric carcinoma cell line (SGC-7901), and to explore their relationship with progression to malignancy of human gastric carcinomas.METHODS:RT-PCR and sequencing were employed to detect the mRNA expression levels of CCK-B receptor and gastrin gene in specimens from 30 patients with gastric carcinoma and healthy bordering non-cancerous mucosa,10 gastritis patients and normal stomachs from 2 autopsied patients as well as SGC-7901.The results were semi-quantified by normalizing it to the mRNA level of β-actin gene using Lab Image software.The sequences were analyzed by BLAST program.RESULTS:CCK-B receptor transcripts were detected in all of human gastric tissues in this study, including normal,inflammatory and malignant tissues and SGC-7901. However,the expression levels of CCK-B receptor in normal gastric tissues were higher than those in other groups (P<0.05),and its expressions did not correlate with the differentiation and metastasis of gastric cancer (P>0.05).On the other hand,gastrin mRNA was detected in SGC-7901 and in specimens obtained from gastric cancer patients (22/30)but not in other gastric tissues,and its expression was highly correlated with the metastases of gastric cancer (P<0.05).CONCLUSION:Human gastric carcinomas and gastric cancer cell line SGC-7901 cells coexpress CCK-B receptor and gastrin mRNA. Gastrin/CCK-B receptor autocrine or paracrine pathway may possibly play an important role in the progression of gastric cancer.展开更多
AIM: To observe the changes of enkephalin mRNA and prodynorphin mRNA in hippocampus of rats induced by chronic immobilization stress.METHODS: Thirty rats were randomly divided into three groups of 10 each: the normal ...AIM: To observe the changes of enkephalin mRNA and prodynorphin mRNA in hippocampus of rats induced by chronic immobilization stress.METHODS: Thirty rats were randomly divided into three groups of 10 each: the normal control group (group A),the group induced by chronic immobilization stress for 7 d (group B) and the group induced by chronic immobilization stress for 21 d (group C). The changes of the enkephalin mRNA and prodynorphin mRNA in the rat hippocampus were detected by reverse transcription-polymerase chain reaction (RT-PCR).RESULTS: Expression levels of enkephalin mRNA and prodynorphin mRNA in rat hippocampus were significantly increased under chronic immobilization stress, and the expression of prodynorphin mRNA in the rat hippocampus in group C was remarkably higher than that in group B (0.624±0.026; n = 5; P<0.01).CONCLUSION: The increased enkephalin mRNA and prodynorphin mRNA gene expressions in rat hippocampus were involved in chronic stress.展开更多
AIM:To evaluate the therapeutic effect of compoundChinese drugs, Jianpiyiwei capsule (JPYW) on gastricprecancerous lesions in rats and to explore itsmechanism of action.METHODS:Model of gastric precancerous lesions wa...AIM:To evaluate the therapeutic effect of compoundChinese drugs, Jianpiyiwei capsule (JPYW) on gastricprecancerous lesions in rats and to explore itsmechanism of action.METHODS:Model of gastric precancerous lesions wasconstructed in male Wistar rats: a metal spring wasinserted and fixed through pyloric sphincter. One weekafter recovery, each rat was given 50-60 ℃ hot pastecontainingt50 g/L NaCl 2 mL orally, twice a week for15 weeks.Then 10 normal and 11 model rats wereanaesthetized, after the measurement of gastricmucosa blood flow (GMBF), the rats were killed andthe mucosal hexosamines and malonic dialdehyde(MDA) were measured. The morphological changes ofgastric mucosa were observed macroscopically andmicroscopically, and by an automatic imaging analysissystem. Other rats were treated with JPYW 1.5 g/kg.d-1or 4.5 g/kg@d-1, or distilled water as negative controlrespectively (n=-10 in each group). After 12 weeks, allthe rats were examined as above.RESULTS: The gastric mucosa of model rats showedchronic atrophic gastritis with dysplasia and intestinalmetaplasia (IM), GMBF and hexosamine content werereduced significantly and MDA was increased ascompared to the normal group (P＜0.01). After 12 weekstreatment, the pathological changes of the negativecontrol group became worsened, while in JPYW treatedgroups the changes were modified with significantincrease of GMBF and reduction of MDA, although thehexosamine concentration increased only mildly.CONCLUSION: JPYW increases GMBF and reduces MDAcontent in gastric mucosa and has therapeutic effectson gastric precancerous lesions.展开更多
The cDNA fragment of human TRAIL (TNF-related apoptosis inducing ligand) was cloned into RevTet-On, a Tetregulated and high-level gene expression system. The gene expression system was constructed in a human leukemic ...The cDNA fragment of human TRAIL (TNF-related apoptosis inducing ligand) was cloned into RevTet-On, a Tetregulated and high-level gene expression system. The gene expression system was constructed in a human leukemic cell line: Jurkat. By using RevTet-On TRAIL gene expression system in Jurkat as a cell model, we studied the influence of TRAIL gene on the changes of cellular apoptosis before and after the TRAIL gene expression, which was induced by adding tetracycline derivative doxycycline (Dox). The results indicated that the cellular apoptosis ratio was largely dependent on the TRAIL gene expression level. Moreover, it was found that the apoptosis-inducing TRAIL could cause significant changes in the biophysical properties of Jurkat cells. The cell surface charge density decreased, the membrane fluidity declined, the elastic coefficients K_I increased, and the proportion of α-helix in membrane protein secondary structure decreased. Thus, the apoptosis-inducing TRAIL gene caused significant changes on the biomechanic properties of Jurkat cells.展开更多
AIM: The role of Pancreatic and Duodenal Homeobox-1(PDX-1) as a major regulator of pancreatic development determines the function and phenotype of β cell. In this study, potential plasticity of liver cells into pancr...AIM: The role of Pancreatic and Duodenal Homeobox-1(PDX-1) as a major regulator of pancreatic development determines the function and phenotype of β cell. In this study, potential plasticity of liver cells into pancreatic endocrine cells induced by PDX-1 was evaluated.METHODS: Human hepatoma cell line HepG2 was stably transfected with mammalian expression plasmid pcDNA3-PDX encoding human PDX-1 gene. Ectopic expression of PDX-1 and insulin were detected by RT-PCR,Western blot and/or immunostaining. PDX-1+ HepG2 cells were transplanted under renal capsule of STZ-induced diabetic nude mice (n = 16) to examine the inducing effect in vivo.RESULTS: Exogenous PDX-1 transgene was proved to express effectively in HepG2 cell at both mRNA and protein levels. The expression of endogenous insulin and some βcell-specific differentiation markers and transcription factors were not induced in PDX-1+ HepG2 cells. When transplanted under renal capsule of STZ-induced diabetic nude mice, PDX-1+ HepG2 cells did not generate insulinproducing cells. These data indicated that stable transfected PDX-1 could not convert hepatoma cell line HepG2 to pancreatic cells in vitro or in vivo. Mature hepatocytes might need much more complicated or rigorous conditions to be shifted to insulin-producing cells.CONCLUSION: The expression of exogenous PDX-1 is not sufficient to induce relatively mature hepatocytes differentiating into insulin-producing cells.展开更多
The relationship between bone mineral density (BMD) and Zn, Cu, Ca levels in the meal and hair of urban and rural elderly people were studied. 470 subjects above 60 years old (urban 205 and rural 265), 178 males with ...The relationship between bone mineral density (BMD) and Zn, Cu, Ca levels in the meal and hair of urban and rural elderly people were studied. 470 subjects above 60 years old (urban 205 and rural 265), 178 males with an average age of 65.70±3.48 and 292 females with an average age of 65.90±4.02, were inquired. The BMD and Zn, Cu, Ca levels in the meal and hair were measured. The detected BMD in urban and rural female old people was significantly lower than that of the males; The contents of Ca and Zn in the meal of the urban females were significantly lower than those of the urban males; The Ca, Zn in the meal and Zn in the hair of the rural females were significantly lower than those of rural males (P< 0.05 or 0.01). The BMD, Ca intakes, Ca and Zn in the hair of the rural old people were significantly lower than those of the urban old people (P< 0 05 or 0.01). There was a correlation between BMD with the Ca, Zn of the hair and dietary Ca, Zn, Cu or between dietary Zn with Ca, Zn in the hair and Ca, Cu intakes. The Zn, Cu and Ca levels in the meal nutrients were correlated with BMD to some degrees. Lack of Ca and Zn in the meal can cause the reduction of BMD.展开更多
The soluble HLA-G1 (sHLA-G1) isoform was found to be secreted by trophoblast cells at the matemo-fetal interface, which suggests that it may act as an immunomodulator during pregnancy. In this paper, we reported that ...The soluble HLA-G1 (sHLA-G1) isoform was found to be secreted by trophoblast cells at the matemo-fetal interface, which suggests that it may act as an immunomodulator during pregnancy. In this paper, we reported that GST-sHLA-G1α chain could bind to its receptor ILT-2 on NK92 cells and then the latter recruited Src homology 2 domaincontaining tyrosine phosphatase-1 (SHP-1), which consequently dephosphorylated some important protein tyrosine kinases and blocked the activation of downstream molecules such as MEK and ERK so that the cytotoxicity of natural killer (NK) cells was inhibited. These results indicated that GST-sHLA-G1α chain might be exploited in new immunotherapy strategies aiming at inducing immunotolerance during allograft, xenograft and autoimmune situations. In addition, we found that modification of O-linked β-N-acetylglucosamine (O-GlcNAc) was involved in NK cells' activating and inhibitory signals. This may provide a novel molecular target for inducing immunotolerance but needs further study.展开更多
The luminous intensity of dark variant (S1) separated from photobacterium phosph oreum (A2) was 1/10 000 less than that of wild type. Ethidium bromide (EB) (0.6 mg/L), Mytomycin C (MC, 0.05 mg/L), 2 amino fluorene ...The luminous intensity of dark variant (S1) separated from photobacterium phosph oreum (A2) was 1/10 000 less than that of wild type. Ethidium bromide (EB) (0.6 mg/L), Mytomycin C (MC, 0.05 mg/L), 2 amino fluorene (2 AF, 1.0 mg/L) all cou ld strongly induce reversion mutation for S1 within 24 h and increase reversion ratio significantly. The results of experiments indicated that these revertants had stable genetic characteristic and the mutation may take place at gene levels . The mutagenesis to S1 caused by EB, MC and 2 AF was detected and it may be us ed as a new rapid, simple and sensitive method for gene toxicant monitoring.展开更多
Objective To partially purify the angiogenesis factor of human osteosarcoma(HuOs) and study its biological features. Methods The active peptide with a molecular weight of 8000-10000 Da in the conditioned medium obtain...Objective To partially purify the angiogenesis factor of human osteosarcoma(HuOs) and study its biological features. Methods The active peptide with a molecular weight of 8000-10000 Da in the conditioned medium obtained from the cultivation of Hu-Os cells(osteoblastic osteosarcoma) was partially purified by ultrafiltration, chromatography and dialysis.The angiogenic effects of the fractions were assessed by proliferation assay of human umbilical vein and pig thoracic aorta endothelial cells. Results The chromatography fractions 4-6 could significantly promote the proliferation of the endothelial cells.Conclusion The HuOs cells could synthesize and secrete angiogenesis factor with a molecular weight of 8000-10000 Da.展开更多
Summary: In order to further investigate the mechanisms of action of berberine (Ber), we assessed the effects of Ber on the mRNA expression of nitric oxide synthases (NOS) in rat corpus cavernosum. After incubation wi...Summary: In order to further investigate the mechanisms of action of berberine (Ber), we assessed the effects of Ber on the mRNA expression of nitric oxide synthases (NOS) in rat corpus cavernosum. After incubation with Ber for 1 or 3 h respectively, the levels of NOS mRNA were examined by reverse transcription polymerase chain reaction (RT-PCR). Our results showed that there were iNOS and eNOS mRNA expressions in rat corpus cavernosum. Ber enhanced eNOS mRNA expression in rat penis, but exhibited no effect on the expression of iNOS mRNA (P>0.05). The present study indicated that the relaxation of Ber involved the NO-cGMP signal thansduction pathway. The enhancing effect of Ber on eNOS mRNA expression might associated with its relaxation of corpus cavernosum.展开更多
Objective: To develop a molecular screening test for genetic defects on hearing loss related genes has significant impacts on early identification of hereditary hearing loss and genetic susceptibility to aminoglycosid...Objective: To develop a molecular screening test for genetic defects on hearing loss related genes has significant impacts on early identification of hereditary hearing loss and genetic susceptibility to aminoglycoside ototoxicity. Early identification of pre-lingual hearing loss is very important for patient’s language development, academic achievement, and social skill. Two common mutations, the 235delC in GJB2 gene and the mutation A1555G in mitochondrial DNA, are included in the newly developed screening panel for Chinese population. Methods: A molecular genetic assay, based on fluorescent labeled multiplex PCR and automatic DNA fragment analyzing techniques, was developed to detect both mutations simultaneously. Results: This assay was able to detect both mutations from patient’s samples, and pooled DNA tests, as well as suitable to detect mutation from the DNA extracted from dried blood spot and buccal swab. Conclusion: This assay could be a useful tool for newborn screening and carrier screening for the hereditary hearing loss for the Chinese population.展开更多
Objective: To construct a specifically targeted gene delivery and expression system, and to investigate the special killing effect of the HSV-tk/GCV system on human liver cancer cells in vitro.Methods: The anti-transf...Objective: To construct a specifically targeted gene delivery and expression system, and to investigate the special killing effect of the HSV-tk/GCV system on human liver cancer cells in vitro.Methods: The anti-transferrin receptor (TfR) ScFv-GAL4 fusion protein expression vector ScFv-GAL4-pET28a and the eukaryotic expression plasmid pEBAF/tk-GAL4rec were constructed by recombinant DNA technology. After the induction by IPTG, we obtained the anti-TfR ScFv-GAL4 fusion protein as delivery vector to transfect pEBAF/tk-GAL4rec into the human liver cancer cell lines HepG2 and SMMC7721 and the human lung cancer cell line A549 that overexpress TfR via receptor-mediated endocytosis. The positive cell clones were selected by hygromycin and named HepG2/tk, SMMC7721/tk and A549/tk,respectively. Cell killing after GCV application was determined by MTT. Results: The correct structure of the ScFv-Gal4 fusion protein and the plasmid pEBAF/tk-GAL4rec was confirmed by double enzyme digestion, SDS-PAGE and sequencing. HepG2/tk cells that express alphafetoprotein (AFP) to high levels(845 ng/ml) were very sensitive to GCV, while SMMC7721/tk cells that express AFP at low levels (2ng/ml) and AFP-negative A549/tk cells were only slightly or not sensitive to GCV. Conclusion: The double-directed and tissue-specific HSV-tk/GCV anti-tumor system shows good targeting to tumor cells.展开更多
To investigate the expression of NOSⅢ mRNA and protein in cultured porcine cerebral arterial endothelial cells (CAEC) during hypoxia and reoxygenation and the effects of L-Tetrahydropalmatine (L-THP) on the gene expr...To investigate the expression of NOSⅢ mRNA and protein in cultured porcine cerebral arterial endothelial cells (CAEC) during hypoxia and reoxygenation and the effects of L-Tetrahydropalmatine (L-THP) on the gene expression of NOSⅢ in CAEC during hypoxia and reoxygenation. The cultured CAEC were divided into 5 groups: control, hypoxia, hypoxia+reoxygenation, hypoxia+L-THP and reoxygenation+L-THP groups. NOSⅢ mRNA expression was detected by reverse transcription-polymerase chain reaction (RT-PCR). Immunocytochemistry was used to detect the level of NOSⅢ protein. The expression of NOSⅢ mRNA and protein were increased when CAEC were exposed to hypoxia for 1 h, and significantly decreased during reoxygenation 2, 6 and 12 h after 1-h of hypoxia. L-THP from 10 -8 mol/L to 10 -3 mol/L could inhibit the up-regulation of NOSⅢ gene expression during hypoxia and down-regulation of NOSⅢ gene expression during reoxygenation.展开更多
基金Supported by the Key Laboratory of Pre-clinical Research for Chinese Herbs and New Drugs of Gansu Province and The Natural Scientific Foundation of Gansu Province, No. ZS021-A25-059-Y
文摘AIM:To study the effects of rhubarb (dried root of Rheum officinale Baill.) on contractile activity of isolated gastric muscle strips of guinea pigs and its possible mechanism. METHODS: A total of 48 guinea pigs were killed to remove the whole stomach. Then, the stomach was opened and the mucosal layer was removed. Parallel to the circular fibers, muscle strips were cut from the body. Each isolated gastric muscle strip was suspended in a tissue chamber containing 5 mL Krebs solution, constantly warmed by water jacket at 37℃ and bubbled continuously with a mixed gas of 950 mL/L O2 and 50 mL/L CO2. After being incubated for 1 h with 1 g tension, rhubarb of varied concentrations (1%, 2%, 7%, 20% and 70%) was added cumulatively into the tissue chamber at intervals of 2 min. Atropine (10-6 mol/L) or isoptin (5x10-8 mol/L) or hexamethonium (10-5 mol/L) was given 2 min before the administration of rhubarb. The isometrical response was measured with an ink-writing recorder. RESULTS: Rhubarb dose dependently increased the resting tension of gastric body circular muscle (CM) (r = 0.726, P<0.05). Atropine (r= 0.829, A:0.05), isoptin (r= 0.764, A;0.05) and hexamethonium (r = 0.797, P<0.05) did not affect its action in a dose-related manner. Atropine apparently reduced the increasing action of 1%, 3%, 10%, 30% and 100% rhubarb on the resting tension of gastric body CM. Isoptin inhibited the effect of 10%, 30% and 100% rhubarb on the resting tension of gastric body CM. Hexamethonium reduced the increasing action of 1%, 10%, 30% and 100% rhubarb on the resting tension of gastric body CM. Rhubarb increased the contractile frequency of CM of body. While atropine, isoptin and hexamethonium did not inhibit the contractile frequency of gastric body CM in comparison with rhubarb at the same concentration, rhubarb at the highest concentration (100%) decreased the mean contractile amplitude of gastric body CM. Atropine, isoptin and hexamethonium did not affect the mean contractile amplitude of gastric body CM compared to rhubarb at the same concentration. CONCLUSION: Rhubarb has exciting actions on isolated gastric smooth muscle strips of guinea pig. The exciting action of rhubarb is partly mediated via cholinergic M receptor, cholinergic N receptor and L-type calcium channel.
基金National Natural Science Foundation of China,No.30200333 and No.30371605
文摘Regenerating gene (Reg or REG) family, within the superfamily of C-type lectin, is mainly involved in the liver,pancreatic, gastric and intestinal cell proliferation or differentiation. Considerable attention has focused on Reg family and its structurally related molecules. Over the last 15 years, 17 members of the Reg family have been cloned and sequenced. They have been considered as members of a conserved protein family sharing structural and some functional properties being involved in injury, inflammation,diabetes and carcinogenesis. We previously identified Reg Ⅳ as a strong candidate for a gene that was highly expressed in colorectal adenoma when compared to normal mucosa based on suppression subtractive hybridization (SSH),reverse Northern blot, semi-quantitative reverse transcriptase PCR (RT-PCR)and Northern blot. In situ hybridization results further support that overexpression of Reg Ⅳ may be an early event in colorectal carcinogenesis. We suggest that detection of Reg Ⅳ overexpression might be useful in the early diagnosis of carcinomatous transformation of adenoma.This review summarizes the roles of Reg family in diseases in the literature as well as our recent results of Reg Ⅳ in colorectal cancer. The biological properties of Reg family and its possible roles in human diseases are discussed. We particularly focus on the roles of Reg family as sensitive reactants of tissue injury, prognostic indicators of tumor survival and early biomarkers of carcinogenesis. In addition to our current understanding of Reg gene functions, we postulate that there might be relationships between Reg family and microsatellite instability, apoptosis and cancer with a poor prognosis. Investigation of the correlation between tumor Reg expression and survival rate, and analysis of the Reg gene status in human maliganancies, are required to elucidate the biologic consequences of Reg gene expression, the implications for Reg gene regulation of cell growth, tumorigenesis, and the progression of cancer. It needs to be further attested whether Reg gene family is applicable in early detection of cancer and whether Reg and Reg-related molecules can offer novel molecular targets for anticancer therapeutics. This has implications with regard to prognosis, such as in monitoring cancer initiation,progression and recurrence, as well as the design of chemotherapeutic drugs.
基金Supported by the Science and Technology commission of JiangsuProvince,No.B J93007 and Natural Science Foundation of JiangsuProvince,No.BK2001003
文摘AIM: To study the effects of phosphorus-32 glass microspheres(^32P-GMS) on human hepatocellular carcinoma in nude mice. METHODS: Human liver cancer cell line was implanted into the dorsal subcutaneous tissue of 40 BALB/c nude mice. Then the 40 tumor-bearing BALB/c nude mice were allocated into treatment group (n=32) and control group (n=8). In the former group different doses of ^32P-GMS were injected into the tumor mass, while in the latter nonradioactive ^31P-GMS was injected into the tumor mass. The experimental animals were sacrificed on the 14th day. The ultrastructural changes of tumor in both treatment group and control group were studied with transmission electron microscopy (TEM) and stereology. RESULTS: In treatment group, a lot of tumor cells were killed and the death rate of tumor cells was much higher (35-70%). UItrastructurally, severe nuclear damage was observed in the death cells. The characteristics of appoptosis such as margination of heterochromatin was also found in some tumor cells. Besides, well differentiated tumor cells, degenerative tumor cells and some lymphocytes were seen. The skin and musde adjacent to the tumor were normal. In control group, the tumor consisted of poorly differentiated tumor cells, in which there were only a few of dead cells (5%). Stereologicl analysis of ultrastructral morphology showed that Vv of nuclei (53.31±3.46) and Vv of nucleoli (20.40±1.84) in the control group were larger than those (30.21±3.52 and 10.96±2.52) in the treatment group respectively (P<0.01), and Vv of RER (3.21±0.54) and Vv of mitochondria (4.53±0.89) in the control group were smaller than those (8.67±1.25 and 7.12±0.95) in the treatment group respectively (P<0.01, 0.05). Sv of the membrane of microvilli and canaliculi (27.12 um^2/100 um^3±11.84 um^2/100 um^3) in the control group was smaller than that (78.81 um^2/100 um^3±19.69 um^2/100 um^3) in the treatment group (P<0.01). But Vv of lipid particles (3.71±1.97) and Vv of vacuoles (5.72±1.58)were much larger than those (0.30±0.16 and 0.35±0.15) in the treatment group respectively (P<0.05, P<0.01). CONCLUSION: The experimental results indicate that local administration of ^32P-GMS can produce obvious effect on liver cancer cells and the anticancer effect of ^32P-GMS is directly proportional to the dose administrated. UItrastructural stereology can also show the effect of ^32P-GMS on the normalization of tumor cells, which is beneficial to the prognosis and treatment of patients. Moreover, local administrtion of ^32P-GMS is also safe.
基金Supported by the 248 Major R&D Program of Beijing,No.H020220020310 and Special Fund for Promotion of Education,Ministry of Education,China
文摘AIM: To analyze the structure and expressions of the protein encoded by an HCC-associated novel gene, lysosomeassociated protein transmembrane 4 β (LAPTM4B). METHODS: Primary structure and fundamental characteristics of LAPTM4B protein were analysed with bioinformatics. Expressions of LAPTM4B in HCC tissues and various cell lines were detected using polyclonal antibodies and Western blot. RESULTS: LAPTM4B encoded two isoforms of proteins with molecular masses 35-ku and 24-ku, respectively. The expression level of LAPTM4B-35 protein in HCC tissues was dramatically upregulated and related to the differentiation status of HCC tissues, and it was also high in some cancer cell lines. Computer analysis showed LAPTM4B was an integral membrane protein with four transmembrane domains. LAPTM4B showed relatively high homology to LAPTM4A and LAPTM5 in various species. CONCLUSION: LAPTM4B gene encoded two isoforms of tetratansmembrane proteins, LAPTM4B-35 and LAPTM4B-24. The expression of LAPTM4B-35 protein is upregulated and associated with poor differentiation in human HCC tissues, and also at high levels in some cancer cell lines. LAPTM4B is an original and conserved protein.
基金Supported by the National Key Technologies Research and Development Program of China during the 10th Five-Year Period,No.2001BA705B06
文摘AIM: To investigate the effect of interleukin-12 p40 gene (IL12E 3'-untranslated region polymorphism on the outcome of HCV infection.METHODS: A total of 133 patients who had been infected with HCV for 12-25 (18.2±3.8) years, were enrolled in this study. Liver biochemical tests were performed with an automated analyzer and HCV RNA was detected by fluorogenic quantitative polymerase chain reaction. B-mode ultrasound was used for liver examination. Polymerase chain reactionrestriction fragment length polymorphism (PCR-RFLP) was used for the detection of IL12B (1188A/C) polymorphism.RESULTS: Self-limited infection was associated with AC genotype (OR = 3.48; P = 0.001) and persistent infection was associated with AA genotype (OR = 0.34; P = 0.014)at site 1188 of IL12B. In patients with persistent HCV infection, no significant differences were found regarding the age, gender, duration of infection and biochemical characteristics (P>0.05). According to B-mode ultrasound imaging and clinical diagnosis, patients with persistent infection were divided into groups based on the severity of infection. No significant differences were found in the frequency of IL-12 genotype (1188A/C) between different groups (P>0.05).CONCLUSION: The polymorphism of II12B (1188A/C)appears to have some influence on the outcome of HCV infection.
基金Supported by the 248 Major R&D Program of Beijing, No. H020220020310, and Special Fund for Promotion of Education, Ministry of Education, China
文摘AM: To produce high-quality potyclonal antibody to lysosomeassociated protein transmembrane 4B-35 and to identify LAPTM4B-35 expression in cancer tissues and its correlation with differentiation status of hepatocellular carcinoma (HCC). METHODS: The 297 bp 5' end of LAPTM4BcDNA was obtained by PCR and inserted into prokaryotic expression vector pGEX-KG. Then the recombinant pGEX-KG-N_(1-99) was transformed into E. coli JM109 to express GST-fusion protein. The fusion protein was purified by glutathione sepharose^(TM) 4B agarose. The purified GST-LAPTM4B-N_(1-99) was characterized by SDSPAGE, and used to immunize rabbits. The titer and specificity of antisera were detected by ELISA and Western blot, respectively. The correlation between the expression levels of LAPTM4B-35 and the differentiation status of HCC was analyzed via Western blot. The expression of LAPTM4B-35 in HCC and other six cancer tissues was investigated via tissue chip and immunohistochemical analysis. RESULTS: About 6.2 mg of pure GST-LAPTM4B-N_(1-99) was isolated from 1 L of bacteria. The GST-LAPTM4B-N_(1-99) produced high titer antisera in rabbits and showed good immunity. Western blot showed specific reactions for the antibody to the LAPTM4B-35 in the total proteins from HCC tissues and BEL-7402 cells, also to the fusion protein purified or in the transformed bacteria. LAPTM4B-35 was remarkably expressed in several cancers, such as HCC, breast cancer, gastric carcinoma, lung cancer, and colon carcinoma, but not commonly expressed in esophageal cancer and rectum carcinoma. Notably, the expression levels of LAPTM4B-35 were significantly and inversely correlated to the differentiation of HCCs in a 20 case analysis. CONCLUSION: Specific polyclonal antibody (LAPTM4BN_(1-99)-pAb) to LAPTM4B-35 was produced. It identified the expression of LAPTM4B-35 in some cancer tissues originated from single layer cuboidal and columnar epithelial cells and firmly demonstrated that the expression of LAPTM4B-35 in HCC was inversely correlated with the differentiation of HCC.
文摘AIM:To compare the expression patterns of cholecystokinin-B (CCK-B)/gastrin receptor genes in matched human gastric carcinoma and adjacent non-neoplastic mucosa of patients with gastric cancer,inflammatory gastric mucosa from patients with gastritis,normal stomachs from 2 autopsied patients and a gastric carcinoma cell line (SGC-7901), and to explore their relationship with progression to malignancy of human gastric carcinomas.METHODS:RT-PCR and sequencing were employed to detect the mRNA expression levels of CCK-B receptor and gastrin gene in specimens from 30 patients with gastric carcinoma and healthy bordering non-cancerous mucosa,10 gastritis patients and normal stomachs from 2 autopsied patients as well as SGC-7901.The results were semi-quantified by normalizing it to the mRNA level of β-actin gene using Lab Image software.The sequences were analyzed by BLAST program.RESULTS:CCK-B receptor transcripts were detected in all of human gastric tissues in this study, including normal,inflammatory and malignant tissues and SGC-7901. However,the expression levels of CCK-B receptor in normal gastric tissues were higher than those in other groups (P<0.05),and its expressions did not correlate with the differentiation and metastasis of gastric cancer (P>0.05).On the other hand,gastrin mRNA was detected in SGC-7901 and in specimens obtained from gastric cancer patients (22/30)but not in other gastric tissues,and its expression was highly correlated with the metastases of gastric cancer (P<0.05).CONCLUSION:Human gastric carcinomas and gastric cancer cell line SGC-7901 cells coexpress CCK-B receptor and gastrin mRNA. Gastrin/CCK-B receptor autocrine or paracrine pathway may possibly play an important role in the progression of gastric cancer.
基金Supported by the National Natural Science Foundation of China,No.30000216,Teaching and Research Award Program for Outstanding Young Teachers in Higher Education Institutes of Ministry of Education,China,Foundation for the Authors of National Excelle
文摘AIM: To observe the changes of enkephalin mRNA and prodynorphin mRNA in hippocampus of rats induced by chronic immobilization stress.METHODS: Thirty rats were randomly divided into three groups of 10 each: the normal control group (group A),the group induced by chronic immobilization stress for 7 d (group B) and the group induced by chronic immobilization stress for 21 d (group C). The changes of the enkephalin mRNA and prodynorphin mRNA in the rat hippocampus were detected by reverse transcription-polymerase chain reaction (RT-PCR).RESULTS: Expression levels of enkephalin mRNA and prodynorphin mRNA in rat hippocampus were significantly increased under chronic immobilization stress, and the expression of prodynorphin mRNA in the rat hippocampus in group C was remarkably higher than that in group B (0.624±0.026; n = 5; P<0.01).CONCLUSION: The increased enkephalin mRNA and prodynorphin mRNA gene expressions in rat hippocampus were involved in chronic stress.
文摘AIM:To evaluate the therapeutic effect of compoundChinese drugs, Jianpiyiwei capsule (JPYW) on gastricprecancerous lesions in rats and to explore itsmechanism of action.METHODS:Model of gastric precancerous lesions wasconstructed in male Wistar rats: a metal spring wasinserted and fixed through pyloric sphincter. One weekafter recovery, each rat was given 50-60 ℃ hot pastecontainingt50 g/L NaCl 2 mL orally, twice a week for15 weeks.Then 10 normal and 11 model rats wereanaesthetized, after the measurement of gastricmucosa blood flow (GMBF), the rats were killed andthe mucosal hexosamines and malonic dialdehyde(MDA) were measured. The morphological changes ofgastric mucosa were observed macroscopically andmicroscopically, and by an automatic imaging analysissystem. Other rats were treated with JPYW 1.5 g/kg.d-1or 4.5 g/kg@d-1, or distilled water as negative controlrespectively (n=-10 in each group). After 12 weeks, allthe rats were examined as above.RESULTS: The gastric mucosa of model rats showedchronic atrophic gastritis with dysplasia and intestinalmetaplasia (IM), GMBF and hexosamine content werereduced significantly and MDA was increased ascompared to the normal group (P＜0.01). After 12 weekstreatment, the pathological changes of the negativecontrol group became worsened, while in JPYW treatedgroups the changes were modified with significantincrease of GMBF and reduction of MDA, although thehexosamine concentration increased only mildly.CONCLUSION: JPYW increases GMBF and reduces MDAcontent in gastric mucosa and has therapeutic effectson gastric precancerous lesions.
基金This work was supported by The National Natural Science Foundation of China(No.30270355,No.39930110)a Doctoral Funding(No.20010001082).
文摘The cDNA fragment of human TRAIL (TNF-related apoptosis inducing ligand) was cloned into RevTet-On, a Tetregulated and high-level gene expression system. The gene expression system was constructed in a human leukemic cell line: Jurkat. By using RevTet-On TRAIL gene expression system in Jurkat as a cell model, we studied the influence of TRAIL gene on the changes of cellular apoptosis before and after the TRAIL gene expression, which was induced by adding tetracycline derivative doxycycline (Dox). The results indicated that the cellular apoptosis ratio was largely dependent on the TRAIL gene expression level. Moreover, it was found that the apoptosis-inducing TRAIL could cause significant changes in the biophysical properties of Jurkat cells. The cell surface charge density decreased, the membrane fluidity declined, the elastic coefficients K_I increased, and the proportion of α-helix in membrane protein secondary structure decreased. Thus, the apoptosis-inducing TRAIL gene caused significant changes on the biomechanic properties of Jurkat cells.
基金the National Natural Science Foundation of China,No. 30240087 the National High Technology Research and Development Program of China, No. 2003AA205090
文摘AIM: The role of Pancreatic and Duodenal Homeobox-1(PDX-1) as a major regulator of pancreatic development determines the function and phenotype of β cell. In this study, potential plasticity of liver cells into pancreatic endocrine cells induced by PDX-1 was evaluated.METHODS: Human hepatoma cell line HepG2 was stably transfected with mammalian expression plasmid pcDNA3-PDX encoding human PDX-1 gene. Ectopic expression of PDX-1 and insulin were detected by RT-PCR,Western blot and/or immunostaining. PDX-1+ HepG2 cells were transplanted under renal capsule of STZ-induced diabetic nude mice (n = 16) to examine the inducing effect in vivo.RESULTS: Exogenous PDX-1 transgene was proved to express effectively in HepG2 cell at both mRNA and protein levels. The expression of endogenous insulin and some βcell-specific differentiation markers and transcription factors were not induced in PDX-1+ HepG2 cells. When transplanted under renal capsule of STZ-induced diabetic nude mice, PDX-1+ HepG2 cells did not generate insulinproducing cells. These data indicated that stable transfected PDX-1 could not convert hepatoma cell line HepG2 to pancreatic cells in vitro or in vivo. Mature hepatocytes might need much more complicated or rigorous conditions to be shifted to insulin-producing cells.CONCLUSION: The expression of exogenous PDX-1 is not sufficient to induce relatively mature hepatocytes differentiating into insulin-producing cells.
基金This project was supported by a grant from natural sci ences foundation of Henan province (964021500).
文摘The relationship between bone mineral density (BMD) and Zn, Cu, Ca levels in the meal and hair of urban and rural elderly people were studied. 470 subjects above 60 years old (urban 205 and rural 265), 178 males with an average age of 65.70±3.48 and 292 females with an average age of 65.90±4.02, were inquired. The BMD and Zn, Cu, Ca levels in the meal and hair were measured. The detected BMD in urban and rural female old people was significantly lower than that of the males; The contents of Ca and Zn in the meal of the urban females were significantly lower than those of the urban males; The Ca, Zn in the meal and Zn in the hair of the rural females were significantly lower than those of rural males (P< 0.05 or 0.01). The BMD, Ca intakes, Ca and Zn in the hair of the rural old people were significantly lower than those of the urban old people (P< 0 05 or 0.01). There was a correlation between BMD with the Ca, Zn of the hair and dietary Ca, Zn, Cu or between dietary Zn with Ca, Zn in the hair and Ca, Cu intakes. The Zn, Cu and Ca levels in the meal nutrients were correlated with BMD to some degrees. Lack of Ca and Zn in the meal can cause the reduction of BMD.
文摘The soluble HLA-G1 (sHLA-G1) isoform was found to be secreted by trophoblast cells at the matemo-fetal interface, which suggests that it may act as an immunomodulator during pregnancy. In this paper, we reported that GST-sHLA-G1α chain could bind to its receptor ILT-2 on NK92 cells and then the latter recruited Src homology 2 domaincontaining tyrosine phosphatase-1 (SHP-1), which consequently dephosphorylated some important protein tyrosine kinases and blocked the activation of downstream molecules such as MEK and ERK so that the cytotoxicity of natural killer (NK) cells was inhibited. These results indicated that GST-sHLA-G1α chain might be exploited in new immunotherapy strategies aiming at inducing immunotolerance during allograft, xenograft and autoimmune situations. In addition, we found that modification of O-linked β-N-acetylglucosamine (O-GlcNAc) was involved in NK cells' activating and inhibitory signals. This may provide a novel molecular target for inducing immunotolerance but needs further study.
文摘The luminous intensity of dark variant (S1) separated from photobacterium phosph oreum (A2) was 1/10 000 less than that of wild type. Ethidium bromide (EB) (0.6 mg/L), Mytomycin C (MC, 0.05 mg/L), 2 amino fluorene (2 AF, 1.0 mg/L) all cou ld strongly induce reversion mutation for S1 within 24 h and increase reversion ratio significantly. The results of experiments indicated that these revertants had stable genetic characteristic and the mutation may take place at gene levels . The mutagenesis to S1 caused by EB, MC and 2 AF was detected and it may be us ed as a new rapid, simple and sensitive method for gene toxicant monitoring.
文摘Objective To partially purify the angiogenesis factor of human osteosarcoma(HuOs) and study its biological features. Methods The active peptide with a molecular weight of 8000-10000 Da in the conditioned medium obtained from the cultivation of Hu-Os cells(osteoblastic osteosarcoma) was partially purified by ultrafiltration, chromatography and dialysis.The angiogenic effects of the fractions were assessed by proliferation assay of human umbilical vein and pig thoracic aorta endothelial cells. Results The chromatography fractions 4-6 could significantly promote the proliferation of the endothelial cells.Conclusion The HuOs cells could synthesize and secrete angiogenesis factor with a molecular weight of 8000-10000 Da.
基金This project was supported by a grant from the National Natural Science Foundation of China (No. 30171151).
文摘Summary: In order to further investigate the mechanisms of action of berberine (Ber), we assessed the effects of Ber on the mRNA expression of nitric oxide synthases (NOS) in rat corpus cavernosum. After incubation with Ber for 1 or 3 h respectively, the levels of NOS mRNA were examined by reverse transcription polymerase chain reaction (RT-PCR). Our results showed that there were iNOS and eNOS mRNA expressions in rat corpus cavernosum. Ber enhanced eNOS mRNA expression in rat penis, but exhibited no effect on the expression of iNOS mRNA (P>0.05). The present study indicated that the relaxation of Ber involved the NO-cGMP signal thansduction pathway. The enhancing effect of Ber on eNOS mRNA expression might associated with its relaxation of corpus cavernosum.
文摘Objective: To develop a molecular screening test for genetic defects on hearing loss related genes has significant impacts on early identification of hereditary hearing loss and genetic susceptibility to aminoglycoside ototoxicity. Early identification of pre-lingual hearing loss is very important for patient’s language development, academic achievement, and social skill. Two common mutations, the 235delC in GJB2 gene and the mutation A1555G in mitochondrial DNA, are included in the newly developed screening panel for Chinese population. Methods: A molecular genetic assay, based on fluorescent labeled multiplex PCR and automatic DNA fragment analyzing techniques, was developed to detect both mutations simultaneously. Results: This assay was able to detect both mutations from patient’s samples, and pooled DNA tests, as well as suitable to detect mutation from the DNA extracted from dried blood spot and buccal swab. Conclusion: This assay could be a useful tool for newborn screening and carrier screening for the hereditary hearing loss for the Chinese population.
文摘Objective: To construct a specifically targeted gene delivery and expression system, and to investigate the special killing effect of the HSV-tk/GCV system on human liver cancer cells in vitro.Methods: The anti-transferrin receptor (TfR) ScFv-GAL4 fusion protein expression vector ScFv-GAL4-pET28a and the eukaryotic expression plasmid pEBAF/tk-GAL4rec were constructed by recombinant DNA technology. After the induction by IPTG, we obtained the anti-TfR ScFv-GAL4 fusion protein as delivery vector to transfect pEBAF/tk-GAL4rec into the human liver cancer cell lines HepG2 and SMMC7721 and the human lung cancer cell line A549 that overexpress TfR via receptor-mediated endocytosis. The positive cell clones were selected by hygromycin and named HepG2/tk, SMMC7721/tk and A549/tk,respectively. Cell killing after GCV application was determined by MTT. Results: The correct structure of the ScFv-Gal4 fusion protein and the plasmid pEBAF/tk-GAL4rec was confirmed by double enzyme digestion, SDS-PAGE and sequencing. HepG2/tk cells that express alphafetoprotein (AFP) to high levels(845 ng/ml) were very sensitive to GCV, while SMMC7721/tk cells that express AFP at low levels (2ng/ml) and AFP-negative A549/tk cells were only slightly or not sensitive to GCV. Conclusion: The double-directed and tissue-specific HSV-tk/GCV anti-tumor system shows good targeting to tumor cells.
基金This projectwas supported by a grantfrom the Key Projectof Science and Technology Brainstorm Program of HubeiProvince ( Serial No. 2 0 0 1AA3 0 7B0 6)
文摘To investigate the expression of NOSⅢ mRNA and protein in cultured porcine cerebral arterial endothelial cells (CAEC) during hypoxia and reoxygenation and the effects of L-Tetrahydropalmatine (L-THP) on the gene expression of NOSⅢ in CAEC during hypoxia and reoxygenation. The cultured CAEC were divided into 5 groups: control, hypoxia, hypoxia+reoxygenation, hypoxia+L-THP and reoxygenation+L-THP groups. NOSⅢ mRNA expression was detected by reverse transcription-polymerase chain reaction (RT-PCR). Immunocytochemistry was used to detect the level of NOSⅢ protein. The expression of NOSⅢ mRNA and protein were increased when CAEC were exposed to hypoxia for 1 h, and significantly decreased during reoxygenation 2, 6 and 12 h after 1-h of hypoxia. L-THP from 10 -8 mol/L to 10 -3 mol/L could inhibit the up-regulation of NOSⅢ gene expression during hypoxia and down-regulation of NOSⅢ gene expression during reoxygenation.
