Adolescent ; Adult ; Child ; Humans ; MELAS Syndrome ; diagnosis ; pathology ; Magnetic Resonance Imaging ; Male ; Tomography, X-Ray Computed

OBJECTIVETo study the role of mitogen activated protein kinase (MAPK)/activator protein-1 (AP-1) pathway in benzo(a)pyrene (B(a)P)-induced changes of cell cycle in human embryo lung fibroblasts (HELF).

METHODSAP-1 luciferase activity was determined by the Luciferase reporter gene assay using a luminometer. The expression levels and activity of extracellular signal-regulated protein kinase (ERK), c-Jun NH2-terminal kinase (JNK) and p38 were determined by Western blot. Flow cytometric analysis was employed to detect the distributions of cell cycle. The dominant negative mutant of ERK2, JNK1 and p38 were applied to detect the upstream or downstream relationship of signaling pathways.

RESULTSB(a)P treatment resulted in a marked activation of AP-1 and its upstream MAPK, including ERK, JNK and p38 in human embryo lung fibroblasts (HELF). B(a)P exposure also led to increase the population of cells at S phase compared to control (P < 0.01) with a concomitant decline of cells at G(1) phase. B(a)P-induced cell cycle alternation was markedly impaired by stable expression of a dominant negative mutant of ERK2 or JNK1, but not p38. B(a)P-induced AP-1 transactivation was inhibited by the overexpression of dominant-negative mutant of ERK2 or JNK1, but not p38. Inhibition of the activation of AP-1 by curcumin, a chemical inhibitor of AP-1, significantly inhibited the cell cycle changes in response to B(a)P treatment.

CONCLUSIONERK and JNK, but not p38, mediated benzo(a)pyrene-induced cell cycle changes by AP-1 transactivation in HELF.

Benzo(a)pyrene ; pharmacology ; Blotting, Western ; Cell Cycle ; drug effects ; Cells, Cultured ; Fibroblasts ; cytology ; drug effects ; metabolism ; Flow Cytometry ; Humans ; Lung ; cytology ; embryology ; Mitogen-Activated Protein Kinase 1 ; metabolism ; physiology ; Mitogen-Activated Protein Kinase 8 ; metabolism ; physiology ; Phosphorylation ; Transcription Factor AP-1 ; metabolism ; p38 Mitogen-Activated Protein Kinases ; metabolism

OBJECTIVETo investigate the roles of cyclin D1/CDK4-E2F-1/4 pathway in cell cycle changes of human embryo lung fibroblasts (HELF) induced by two different benzo(a)pyrene [B(a)P] treatment models.

METHODSTwo B(a)P treatment models: HELF were treated by 2 micromol/L B(a)P for 24 hours; HELF were treated by 100 micromol/L B(a)P three times 24 hours each and provide with some characteristics of transformed cells (T-HELF). Changes of cell cycle and the expression of cyclin D1, CDK4 and E2F-1/4 were checked using the flow cytometry and Western bolt analysis.

RESULTSAfter 24 hours 2 microml/L B(a)P treatment, the HELFs in the G(1) phase was decreased. In HELF transfected with antisense cyclin Dl (A-Dl) and antisense CDK4 (A-K4), the expression of cyclin Dl and CDK4 blocked the cell cycle changes from the G(1) phase to the S phase induced by B(a)P. The overexpression of cyclin Dl and E2F-1 in HELF was induced by B(a)P. The E2F-1 overexpression in A-D1 induced B(a)P was inhibited. The E2F-4 expression was decreased and the CDK4 expression was increased significantly in A-K4 after B(a)P treatment. Most of T-HELF transfected with antisense cyclin Dl (T-A-Dl) and antisense CDK4 (T-A-K4) were retained in G(1) phase. The cyclin Dl expression in T-HELF was increased significantly compared with that in HELF. The E2F-4 expression in T-A-Dl and T-A-K4 was increased significantly compared with that in T-HELF.

CONCLUSIONB(a)P induces the cell cycle changes through cyclin D1/CDK4-E2F-1/4 pathway in HELF treated by 2 micromol/L B(a)P while it induces cell cycle changes through cyclin D1/CDK4-E2F-4 pathway in T-HELF.

Benzo(a)pyrene ; pharmacology ; Blotting, Western ; Cell Cycle ; drug effects ; Cells, Cultured ; Cyclin D1 ; biosynthesis ; Cyclin-Dependent Kinase 4 ; biosynthesis ; Dose-Response Relationship, Drug ; E2F1 Transcription Factor ; biosynthesis ; E2F4 Transcription Factor ; biosynthesis ; Fibroblasts ; cytology ; drug effects ; metabolism ; Flow Cytometry ; Humans ; Lung ; cytology ; embryology

OBJECTIVETo explore the role of telomerase in asbestos dust induced malignant transformation of human embryonic lung fibroblasts in vitro.

METHODSHuman telomerase catalytic subunit (hTERT) was transferred into human embryonic lung fibroblasts (HELF). Chrysotile dust at concentration of 2.5 microg/cm(2) was added to HELF transduced with and without hTERT (HELF-T+), respectively, and their transduced foci were separated. Biological characteristics of the cells, telomerase activity, length of telomere and cell growth curve were observed. Colony forming test was performed on soft agar to evaluate the nature of transformation.

RESULTSThe hTERT gene was transferred into HELF steadily, and HELF-T+ was established. Malignant transformation occurred in both HELF and HELF-T+ by asbestos stimulation. Asbestos dusts could induce higher rate of transformations in HELF-T+ [(2.08 +/- 1.08)/utensil] than in HELF [(1.08 +/- 0.10)/utensil], P < 0.05. Telomerase activity in both transformed malignant cells and HELF-T+ was higher, as well as the longer length of telomere in them.

CONCLUSIONRate of malignant transformation in cells with more activity of telomerase and longer length of the telomere was higher after stimulation with asbestos, indicating telomerase could play an important role in asbestos induced human cells malignant transformation.

Asbestos, Serpentine ; toxicity ; Cell Transformation, Neoplastic ; drug effects ; Cells, Cultured ; DNA-Binding Proteins ; Embryo, Mammalian ; Fibroblasts ; pathology ; Gene Transfer Techniques ; Humans ; Lung ; pathology ; Telomerase ; genetics ; metabolism

OBJECTIVETo explore the effects of excessive fluoride on the gene expression of rat osteoblasts.

METHODSRat osteoblasts were treated with 2.0 mmol/L of sodium fluoride (NaF) for two weeks in vitro, and difference in the gene expression between the NaF-treated and normal osteoblasts was compared with mRNA differential display (DD-PCR) technique.

RESULTSAmong the six differentially expressed gene fragments which had been cloned, expression of the ribosomal protein L5 gene, ATPase Na(+)K(+) transporting beta polypeptide 3 gene, karyopherin alpha 2 gene and cis-Golgi body p28 gene was lower and expression of ubiquitous-conjugating enzyme E2D 3 gene and a newly-discovered gene fragment in this study showed up-regulated in the NaF-treated osteoblasts of the rats.

CONCLUSIONSExpression of genes changed in the osteoblasts after treatment with fluoride for two weeks and most of them associated with synthesis, transportation and processing of protein. It suggested that excessive fluoride could affect the protein synthesis in osteoblasts by changing the expression of the related genes. A novel gene related to excessive fluoride exposure was also found.

Animals ; Base Sequence ; Cells, Cultured ; Cloning, Molecular ; DNA, Complementary ; genetics ; Fetus ; Gene Expression Profiling ; Molecular Sequence Data ; Osteoblasts ; cytology ; Polymerase Chain Reaction ; Rats ; Rats, Sprague-Dawley ; Sequence Analysis, DNA ; Skull ; pathology ; Sodium Fluoride ; toxicity

OBJECTIVETo investigate the effects of excessive intake of fluoride on the expression of type II collagen gene and types and morphological change of collagen fiber in the bone tissues of rats.

METHODSA rat model with fluorosis was established by adding 221 mg/L of sodium fluoride (NaF) to drinking water for the rats for 15 days, 30 days and two months, respectively. Type II collagen alpha1 (II) cDNA probe was prepared, and cDNA-mRNA in-situ hybridization was employed to detect change in expression of type II collagen mRNA in the bone tissues of rats with excessive intake of fluoride (221 mg/L NaF). Picrosirius-polarization method was used to observe types of collagen and morphology of collagen fiber in the bone tissues.

RESULTSChondroblasts were found in the femur and other bone tissues of the rats after exposure to fluoride. cDNA-mRNA in-situ hybridization showed that expression of type II collagen gene could be observed in the cytoplasm of chondrocytic lacuna and chondrified bone tissues. mRNA in collagen of chondrocytes of the rib cartilage reached the peak level 15 days after exposure to fluoride, and decreased gradually one month and two months after exposure. Polychromatic type II collagen, breakage of collagen fiber, disorder array and reduced content of type II collagen could be found in the bone tissues with picrosirius-polarization method.

CONCLUSIONSExcessive intake of fluoride could lead to changes in types and structure of collagen (cross-linkage) of bone tissues, which caused expression of type II collagen gene in the chondrified bone tissues and enhanced its expression in the rib cartilage tissues.

Animals ; Bone Diseases ; metabolism ; pathology ; Chondrocytes ; metabolism ; Collagen Type II ; biosynthesis ; genetics ; Fluoride Poisoning ; genetics ; metabolism ; pathology ; Male ; RNA, Messenger ; biosynthesis ; genetics ; Rats ; Rats, Wistar

OBJECTIVERenal interstitial fibrosis is the final common pathway leading to end-stage renal failure for progressive renal disease of various types. The present study was undertaken to add to the knowledge on colchicine's antiinflammatory and antifibrotic properties confirmed by both human and experimental studies. As the main effector cells, fibroblasts have a central role in the pathogenesis of renal fibrosis. This study aimed to investigate the effects of colchicine on the synthesis and excretion of cytokines transforming growth factor-beta1 (TGF-beta1), interleukin-1beta (IL-1beta) and extracellular matrix (collagen III, collagen IV) in human renal fibroblast.

METHODSVarious concentrations of colchicine (5.0 micromol/L, 10.0 micromol/L, 20.0 micromol/L, 40.0 micromol/L) were used to pretreat human embryo renal fibroblasts for 1 hour which were cultured in vitro and then stimulated by 10.0 microg/ml of lipopolysaccharide (LPS). After 18 hours, these fibroblasts and their supernatant were collected. The expression of TGF-beta1 mRNA, IL-1beta mRNA in the cells was studied by using RT-PCR, and the excretion of TGF-beta1, IL-1beta, collagen III and collagen IV by the fibroblasts was assessed by ELISA respectively.

RESULTS(1) By pure stimulation with 10.0 micro g/ml LPS, the expression of TGF-beta1 mRNA and IL-1beta mRNA of fibroblasts was up-regulated 3 times (66.1 +/- 1.6 vs. 22.3 +/- 2.0, q = 590.5, P = 0.002) and 4.7 times (22.0 +/- 2.2 vs. 4.7 +/- 0.8, q = 106.8, P = 0.009), respectively. The protein excretion of TGF-beta1 and IL-1beta was remarkably increased as well compared with the control group [TGF-beta1: (516 +/- 14) pg/ml vs. (420 +/- 5) pg/ml (q = 80.3, P = 0.012), IL-1beta: (3.4 +/- 0.3) pg/ml vs. (0.3 +/- 0.1) pg/ml (q = 297.9, P = 0.003)]. (2) Colchicine could inhibit the expression of TGF-beta1 mRNA and protein in a dose-dependent manner. IL-1beta mRNA and protein were both up-regulated by colchicine. (3) LPS could not stimulate the excretion of extracellular matrix by fibroblasts, but the excretion of collagen III and collagen IV was down regulated by colchicine in a dose-dependent manner.

CONCLUSION(1) The expression of TGF-beta1 mRNA and the excretion of TGF-beta1 protein in the fibroblasts was significantly suppressed by colchicine, while the expression of IL-1beta mRNA and the excretion of IL-1beta protein were enhanced. (2) Colchicine has significant inhibitory effect on the excretion of extracellular matrix such as collagen III and collagen IV in fibroblasts.

Colchicine ; pharmacology ; Cytokines ; metabolism ; Enzyme-Linked Immunosorbent Assay ; Extracellular Matrix ; metabolism ; Fibroblasts ; drug effects ; metabolism ; Gene Expression ; drug effects ; Gout Suppressants ; pharmacology ; Humans ; Interleukin-1 ; genetics ; metabolism ; Kidney ; cytology ; drug effects ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Transforming Growth Factor beta ; genetics ; metabolism ; Transforming Growth Factor beta1

The present study aimed at investigating the effects of chronic multiple stress on learning and memory functions of rats. Adult male Wistar rats were randomly divided into stressed and control groups. Rats in the stressed group were irregularly and alternately exposed to the situation of vertical revolution, sleep deprivation, noise stimulation, and night illumination 6 h per day for 6 weeks to prepare a chronic multiple stressed model. Learning and memory performance of rats was measured by using Morris water maze first and Y-maze afterwards. Neurons in the dentate gyrus(DG), CA3 and CA1 regions of the hippocampus were stained by using Cresyl violet method and counted. The results showed that: (1) After chronic multiple stress, compared with the control rats, the escape latency to the hidden platform in Morris water maze was significantly shortened in stressed rats. In stressed and control groups, the escape latency periods were (15.89+/-9.15) s and (27.30+/-12.51) s, respectively, indicating that spatial memory of the stressed rats was stronger than that of the control ones. In brightness-darkness discrimination learning in the Y- maze, the correct trials and correct percentage of entering safe arm was remarkably increased in the stressed rats, the correct rates of stressed and control groups were (79.01+/-1.23)% and (66.12+/-1.61)%, respectively, indicating that brightness-darkness discrimination learning ability of the stressed rats was better than that of the control ones. (2) After chronic multiple stress, nerve cell density in DG, CA1 and CA3 of the hippocampus in stressed rats was higher than that of the control group, the cell densities in DG, CA1 and CA3 of the stressed and the control group were (223.78+/-26.52), (112.07+/-14.23) and (105.55+/-18.12) as well as (199.13+/-15.36), (92.89+/-13.69), and (89.02+/-15.77) respectively. These results suggest that the chronic multiple stress may enhance the capability of spatial memory and brightness-darkness discrimination learning of rats. Possible reasons for the chronic multiple stress-induced learning and memory enhancement of rats were also discussed.
Animals ; Hippocampus ; physiology ; Learning ; physiology ; Male ; Maze Learning ; Memory ; physiology ; Neuronal Plasticity ; physiology ; Rats ; Rats, Sprague-Dawley ; Spatial Behavior ; physiology ; Stress, Physiological ; physiopathology

OBJECTIVETo assess the advantage and disadvantage of laparoscopic abdomino-perineal resection and open abdominoperineal resection for low rectal cancer.

METHODSPatients with low rectal cancer, collected from July 2003 to April 2006, were randomly divided into laparoscopic abdominoperineal resection group (37 cases) and open abdominoperineal resection group (37 cases). Operation time, number of lymph node removed, intra-operative blood loss, time to pass flatus, time to ambulate, time to discharge, complications, early recurrence, and economical cost were compared between the 2 groups.

RESULTSAll patients were performed successfully. For the first 10 patients, operation time of laparoscopic group was significantly longer than that of open group, but there was no significant difference between the 2 groups. Intra-operative blood loss of laparoscopic group was significantly less than that of open group, but it was reverse for the first 10 patients. There was no significant difference in time to pass flatus between the 2 groups. Time to ambulate in laparoscopic group was significantly earlier than that in open group. There was no significant difference in time to discharge between the 2 groups, but it was earlier for perineum closure in laparoscopic group. Relative complications of laparoscopic group, including pulmonary infection, abdominal wound infection or split, were significantly less than those of open group. There was no significant difference in number of lymph nodes removed, early recurrence between the 2 groups. Operation cost of laparoscopic group was significantly higher than that of open group, but there was no significant difference.

CONCLUSIONAdvantages of laparoscopic abdominoperineal resection were characterized for not only minimal invasion and good cosmetic outcome but also less blood loss, complications, and earlier postoperative recovery. The operation time, total costs and oncological clearance of laparoscopic abdominoperineal resection patients were comparable with those of open procedure patients.

Abdomen ; surgery ; Aged ; Female ; Humans ; Laparoscopy ; Male ; Middle Aged ; Perineum ; surgery ; Rectal Neoplasms ; pathology ; surgery ; Rectum ; pathology ; surgery ; Treatment Outcome

OBJECTIVETo study the molecular mechanism of the inhibitory effects of vitamin C on benzo[a]pyrene (B[a]P)-induced changes of cell cycle in human embryo lung fibroblast (HELF) cells.

METHODSThe stable transfectants, HELF transfected with antisense cyclin D1 and antisense CDK4, were established. Cells were cultured and pretreated with vitamin C before stimulation with B[a]P for 24 h. The expression levels of cyclin D1, CDK4, E2F1, and E2F4 were determined by Western blot. Flow cytometric analysis was employed to detect the distributions of cell cycle.

RESULTSB[a]P significantly elevated the expression levels of cyclin D1, E2F1, and E2F4 in HELF cells. Vitamin C decreased the expression levels of cyclin D1, E2F1, and E2F4 in B[a]P-stimulated HELF cells. Dose-dependent relationships were not found between the different concentrations of vitamin C (10, 100, 500, 1000, and 5000 micromol/L) and the expression levels of cyclin D1, E2F1, and E2F4 in HELF cells. The expression levels of cyclin D1, E2F1, and E2F4 in B[a]P-treated transfectants were lower than those in B[a]P-treated HELF cells. The expression levels of cyclin D1 and E2F4 treated with vitamin C and antisense cyclin D1 were decreased compared with those treated with antisense cyclin D1 alone. The effects of vitamin C combined with antisense CDK4 on the expression levels of cyclin D1 and E2F1/E2F4 were similar to those of antisense CDK4 alone. B[a]P progressed HELF cells from G1 to S phase. Both vitamin C and antisense cyclin D1 suppressed the changes of cell cycle progressed by B[a]P. However, antisense CDK4 did not attenuate the above changes. Vitamin C combined with antisense CDK4 markedly suppressed B[a]P-induced changes of cell cycle as compared with antisense CDK4. But the inhibitory effects of vitamin C combined with antisense cyclin D1 on B[a]P-induced changes of cell cycle were similar to those of vitamin C alone or antisense cyclin D1 alone.

CONCLUSIONSB[a]P progressed HELF cells from G1 to S phase via intracellular signaling pathway of cyclin D1/E2F. Vitamin C may modulate this signaling pathway to protect cells from injury caused by B[a]P.

Ascorbic Acid ; pharmacology ; Benzo(a)pyrene ; Blotting, Western ; methods ; Cell Cycle ; drug effects ; physiology ; Cells, Cultured ; Cyclin D1 ; metabolism ; Cyclin-Dependent Kinase 4 ; metabolism ; Dose-Response Relationship, Drug ; E2F1 Transcription Factor ; metabolism ; Fibroblasts ; cytology ; drug effects ; metabolism ; G1 Phase ; drug effects ; physiology ; Humans ; Lung ; cytology ; embryology ; RNA, Antisense ; genetics ; S Phase ; drug effects ; physiology ; Transfection ; methods