Biomedical subjects

J Chen

Publications and source records attributed to J Chen.

At least 667 records · Page 37Linked to original sources

PubMed2001

[The effects of sodium butyrate on proliferation, differentiation and apoptosis in immortalized esophageal epithelial cells].

OBJECTIVE: To study the effects of sodium butyrate on proliferation, differentiation and apoptosis of immortalized esophagus epithelial cells. METHODS: SHEE, an immortalized human fetal esophageal epithelial cell line induced by HPV18 E6E7, was cultivated in culture flasks and 24-well plates. Two experiment groups of cultured cells were treated with 1 and 5 mmol/L of sodium butyrate respectively for 4 days, and one group of untreated cells set aside as control. The numbers of cloned cells were calculated. The ultra-structure of SHEE cells was examined by transmission electron microscopy (TEM). The cell cycle and number of apoptotic cells were measured by flow cytometry, Ki-67 and cytokeratin of cells were detected by immunohistochemistry method and F-actin of cells labeled with phalloidin was examined by laser confocal scanning microscopy. RESULTS: Colony formations showed a significant decrease in the 2 experiment groups after 4 days of culture (P < 0.01). In the 1 mmol/L group, the cells at S phase were diminished and arrested at G(0)/G(1) phase. Compared with control group, Ki-67 positive cells were found decreased, while F-actin and cytokeratin were increased. Apoptotic cells in 5 mmol/L group were increased markedly. CONCLUSIONS: Sodium butyrate may induce SHEE cells growth arrest, differentiation and apoptosis. The effects depend on sodium butyrate concentration and time of exposure. Whether it can be used in combination with other anticancer drugs should be further studied.

Actins↗

PubMed2001

[Effects of hypoxia on the expression of protein kinase C mRNA in pulmonary artery smooth muscle and endothelial cell].

OBJECTIVE: To investigate the effects of hypoxia on the expression of PKC mRNA in pulmonary artery smooth muscle cells (PASMC) and endothelial cells. METHODS: In situ hybridization technique was used to detect the expression of PKC mRNA in different segments of pulmonary artery smooth muscle and endothelial cell (EC) in rats, and the effect of hypoxia on the expression of PKC alpha mRNA in pulmonary artery smooth muscle and endothelial cells in vivo and in vitro. RESULTS: PKC alpha mRNA was expressed in normal PASMC and EC in rats. The expression of PKC alpha mRNA was higher in the PASMC of intra-acinar pulmonary arteriole than that of muscular arteriole (P < 0.01). In 14 and 28 days of hypoxia, the expression of PKC alpha mRNA was higher both in EC of intraacinar pulmonary arteriole and muscular arteriole and PASMC of intra-acinar pulmonary arteriole (P < 0.01). After 14 days of hypoxia, the expression of PKC alpha mRNA was not significantly changed. But by 28 days, it became significantly higher (P < 0.01). PKC alpha mRNA was expressed in normal PASMC and EC in pigs in vitro. After 1 h of hypoxia, no change was detected, but PKC alpha mRNA expression was significantly higher after 48 h and 72 h of hypoxia in PASMC and EC in vitro (P < 0.01). CONCLUSIONS: Hypoxia can promote expression of PKC alpha m RNA in PASMC and EC, especially in the PASMC of intra-acinar pulmonary arterioles. PKC alpha may play an important role in the development of hypoxia pulmonary hypertension.

Animals↗

PubMed2001

[Pathomorphologic features of clinical stage A prostate carcinoma and causes for misdiagnosis and missed diagnosis].

OBJECTIVE: To study the pathomorphologic features and causes for misdiagnosis and missed diagnosis of clinical stage A prostate carcinoma. METHODS: Prostate samples from a series of 1 020 prostate resections performed in five Shanghai hospitals were obtained, from which 50 clinical stage A carcinoma were studied by immunohistochemistry, according to tumor differentiation and their volume, they were divided into stage A1 and A2 disease. The pathomorphologic features of stage A1 and A2 disease were compared, and the causes for misdiagnosis were analysed. RESULTS: Stage A1 cancer were well- or moderately well-differentiated, of low volume and tended to be multifocal; Stage A2 cancers were poorly differentiated, of high volume, diffuse infiltration and with high grade prostatic intraepithelial neoplasia. 8 cases were misdiagnosed of which 7 cases were stage A1 and misdiagnosed as benign proliferous small gland lesions and 1 case of A2 disease was misdiagnosed as epithelioid histiocytic reactive proliferation. CONCLUSIONS: Stage A1 cancer tended to be initiated in the transition zone and the central zone of the hyperplastic prostate. Stage A2 cancers were mostly middle grade to high grade cancers initiated in the peripheral region and then invaded the central area. The lower incidence of stage A carcinoma in China is related to the small amount of biopsy tissue, careless microscopic observation, or lack of the ability to diagnose stage A1 cancer.

Aged↗

PubMed2001

[Detection of the expression of Smad4, transforming growth factor beta(1) and beta receptor II proteins in paraffin-embedded human pancreatic cancer tissues].

OBJECTIVE: To explore the relationships between Smad4, TGF beta1 and TbetaR II in the TGF-beta pathway and the possible mechanisms by which they effect pancreatic carcinoma. METHODS: The expression of Smad4, TGF beta1 and TbetaR II in paraffin embedded pancreatic carcinoma tissues was detected by using antibodies against Smad4, TGF beta1 and TbetaR II with EnVision immunohistochemistry. RESULTS: The positive rates of Smad4, TGF beta1 and TbetaR II were 58.93% (33), 66.07% (37) and 60.71% (34), respectively. The positive rates of the above three proteins in matched normal pancreatic tissues were 89.29% (50), 25.00% (14) and 25.00% (14) respectively. There was a significant relationship between the expression of TGF beta1, clinical stage and the metastasis of the tumor (P < 0.05). There was also a significant relationship between the expressions of TGF beta1 and TbetaR II (P < 0.05). CONCLUSIONS: The expression of Smad4 in pancreatic carcinoma tissue is significantly decreased but the expression of TGF beta1 and TbetaR II are increased. Smad4 may play an important role in the regulation of TGFbeta inducible gene expression and subsequent growth inhibition, but TGFbeta may also act in a Smad4-independent manner.

DNA-Binding Proteins↗

PubMed2001

[The management of bony burn with skin flap transplant with preservation of sequestrum].

OBJECTIVE: To study the management of bony burn, so as to improve the quality of bony burn treatment, to decrease the complications and to shorten the course. METHODS: Retrospective review of 36 cases with bony burn cured since 1992 was done in terms of treatment strategy before skin flap transplant to cover the burn wound, i e sequestrum preserved or partial removal. RESULTS: There exhibited no complications, such as infection, osteomyelitis and pathologic bone fracture in all these cases. CONCLUSION: The treatment strategy described here could be advocated in view of its reliable coverage of the wound, shortening of the bony burn course and reduction of complication.

Adolescent↗

PubMed2001

[The predictive value of serum neopterin for multiple organ dysfunction syndrome in extensively burned patients].

OBJECTIVE: To evaluate the predictive value of serum neopterin for multiple organ dysfunction syndrome (MODS) in extensively burned patients. METHODS: Twenty-nine burn patients with TBSA of more than 70% were included in this study, and these patients were divided into two groups according to the occurrence of MODS. Blood samples were obtained on 1, 3, 7, 14, 21 and 28 postburn days (PBDs). And serum neopterin levels were determined by radioimmunossay. To evaluate the predictive power of neopterin, sensitivity, specificity, predictive value of a positive/negative test were calculated for the diagnosis of MODS. RESULTS: Serum neopterin levels in MODS group were significantly higher than those in non-MODS group on 3, 7, 14 and 21 PBDs (P < 0.05 similar 0.01). And a positive correlation was found between neopterin levels and MODS scores in patients who developed MODS on 3, 7 and 21 PBDs (r = 0.470 similar 0.811). In a period of up to 28 PBDs, neopterin levels exceeding 35.0 nmol/L were associated with MODS by a clinical sensitivity of 81.1%, a specificity of 89.9%, a positive predictive value of 81.1%, and a negative predictive value of 89.9%. CONCLUSION: These data indicated that the presence of constant high neopterin serum levels appear to be associated with the development of postburn MODS. Serum levels of neopterin might be a useful marker for the early identification of extensive burned patients at risk for MODS.

Adolescent↗

PubMed2001

[An experimental study on systemic inflammatory response syndrome induced by subeschar tissue fluid].

OBJECTIVE: To investigate the effects of subeschar tissue fluid (STF) on normal rats and their peritoneal macrophages in vitro, so as to explore its relationship with inflammatory mediators. METHODS: Eighteen Wistar rats were evenly and randomly divided into three groups, i.e. STF, normal human serum control and blank control groups. The changes of the heart and respiratory rates of rats in every group were recorded by two channel physiological recorder. Blood samples were collected for the determination of hepatic and renal function. The hepatic, pulmonary, renal and cardiac tissues were harvested for routine morphological examination. The changes of the secretion of TNFalpha, IL-1 were also determined. RESULTS: The heart and respiratory rates increased after the infusion of STF, and leukocyte count increased along with different degrees of injury to lungs, liver and kidneys. It was indicated in in vitro experiment that STF could activate macrophage and stimulate the secretion of TNFalpha and IL-1 from the macrophage. CONCLUSION: STF might induce the development of SIRS in rats, which further lead to the development of MODS.

Animals↗

PubMed2001

[Autologous dendritic cells eliciting cytotoxicity of bone marrow cells against chronic granulocytic leukemia].

OBJECTIVE: To investigate the activity of bone marrow cells activated by autologous dendritic cells (DC) to mediate cytotoxicity against chronic granulocytic leukemia (CGL) cells. METHODS: DC were separated from bone marrow mononuclear cells (BMMNC) of two CGL patients in hematological remission and harvested after 3 days of culture in IMDM containing autologous plasma, rhGM-CSF and rhTNFalpha at 37 degrees C, 5% CO(2) humidified atmosphere. BMMNC obtained from the patients were divided into 3 groups to set up Dexter systems: the control group, rhIL-2 containing, and the third group having DC added at day 4. After 10 days of culture, non-adherent cells were harvested and the changes of immunological phenotype and the percentage of P210 positive cells were analyzed. The cytotoxicity were assayed with two-colour flow cytometry. The non-adherent cells from all the 3 systems served as effector cells, those from control system as target cells. RESULTS: The cytotoxic activity against target cells was greater in the DC-activated effector cells than that in rhIL-2-activated ones. The percentages of death cells in target cells were 63.12% versus 42.59% (case 1) and 61.60% versus 21.46% (case 2), respectively. In addition, there was a marked increase in the death cell percentage in the DC-activated effector cells themselves after incubation with target cells. This phenomenon was not found in the rhIL-2-activated effector cells. The percentage of P210 positive cells was significantly lower in non-adherent cells after 10 days of culture in Dexter system, comparing with that in non-cultured BMMNC. The least P210 positive cells were found in those cultured with DC and the less in those with rhIL-2. CONCLUSION: Autologous DC were able to activate bone marrow cells to generate cytotoxicity against CGL cells. Their effect was greater than that of rhIL-2. These activated bone marrow cells might mediate graft versus leukemia effect in vivo.

Bone Marrow Cells↗

PubMed2001

[Effects of metal ions on gamma-poly (glutamic acid) synthesis by Bacillus licheniformis].

In the course of gamma-poly (glutamic acid) gamma-PGA fermentation, metal ions K+, Mg2+, Fe3+, Ca2+, Mo6+, Mn2+, Co2+ and Zn2+ in the medium have certain effects on the synthesis of gamma-poly(glutamic acid). Excess or lack of K+, Mg2+ and Fe3+ results in reduced yield of gamma-PGA. It was found that the gamma-PGA synthesis by Bacillus licheniformis was promoted obviously by Ca2+ and Mo6+. Synthesis and stereochemical composition of gamma-PGA was greatly regulated by Mn2+. gamma-PGA was not produced without Mn2+ in medium, and with the increase of Zn2+ concentration the yield of gamma-PGA and the proportion of D-glutamic acid in the peptide increase. Regulative effect of Co2+ and Zn2+ was almost the same as that of Mn2+, thus the combination of Mn2+, Co2+ cannot enhance gamma-PGA synthesis and affect stereochemical composition of gamma-PGA. Based on the experimental date, an appropriate formulation of metal ions in the medium for gamma-PGA production was obtained.

Bacillus↗

PubMed2001

[Technical causes of false and inferior species appearing in Chinese medicinal materials markets].

The result indicated that technical causes of false and inferior appearing in the Chinese medicinal materials markets consisted of two respects essentially. First, the men who violated the law and committed a crime used certain weak link existing in quantity analysis of country's medicinal standard. Second, it is difficult that basic units managing and using drug implement effective technical supervision.

Drugs, Chinese Herbal↗

PubMed2001

Effect of acupuncture on plasmic levels of insulin, glucagon and hypercoagulability in NIDDM complicated by acute cerebral infarction.

Twenty-one cases of acute cerebral infarction secondary to NIDDM were treated with acupuncture and conventional therapy, and compared with 16 cases treated with conventional therapy alone. The results showed that acupuncture was more effective in reducing insulin and glucagon levels (P < 0.001) and improving hypercoagulability (P < 0.05) of blood.

Acupuncture Therapy↗

PubMed2001

Studies on the development of DNA vaccine against Cysticercus cellulosae infection and its efficacy.

DNA vaccine against Cysticercus cellulosae infection was developed and its efficacy was tested. A pair of primers specific to antigen B gene of C. cellulosae was designed which amplified the gene successfully with RT-PCR. The gene was ligated to PV93 vector, and the recombinant of antigen B gene and PV93 was transformed to JM83 cells. The transformed JM83 cells were cultured in a large scale and the plasmid purified. Based on the recombinant plasmid. a DNA vaccine was developed and used to vaccinate two groups of experimental pigs. In each group, there was a routine vaccine, an enhanced vaccine and a control group. Groups 1 and 2 were challenged at 4 months and at 14 days post vaccination respectively with eggs of Taenia solium. The antibody response was also tested with ELISA. The results suggested that all animals vaccinated AgB gene DNA vaccine, no matter by routine or enhanced vaccine, their antibodies reached maximum peak 23 days post vaccination and decreased gradually. When the animals were challenged 4 months after vaccination, they had strong immunity and the parasites decrease rates were 91.2% and 93.1% respectively. When pigs vaccinated with AgB gene DNA vaccine were challenged 14 days post vaccination with 18,000 eggs/pig. The animals showed strong immunity and the parasite decrease rates were 99.5% and 84.9% respectively. However at that time, the antibodies did not reach the peak. While in the control group, the number of C. cellulosae was as many as 2,500. It was concluded that the pigs vaccinated with DNA vaccine had strong immunity against infection of eggs of T. solium.

Animals↗

PubMed2001

[Malignant transformation of human bronchial epithelial cells induced by benzo(a)pyrene metabolite dihydroxyepoxy benzo pyrene].

The malignant transformation of human bronchial epithelial cell 16HBE induced by benzo (a) pyrene metabolite--dihydroxyepoxy benzo pyrene (BPDE) was studied. 16HBE cells were treated several times with BPDE at different concentrations in vitro. The identification on the malignancy of transformed 16HBE cells was investigated. The transformed cells in foci were proliferated rapidly, exhibited in extensive random orientation and crossed over. The transformed cells could grow on soft agar. The colony forming frequency of each BPDE group on soft agar was significantly higher than that of control group and showed dose-reaction relations with the concentrations of BPDE. The transformed cells could grow into tumors in nude mice. The tumor was squamose carcinoma confirmed by histopathological examination. The culture system in this study provided a potential tool for studying the molecular mechanism of carcinogenesis of human bronchial epithelial cells induced by BPDE.

7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide↗

PubMed2001

[Effect of exercise on leptin in streptozotocin-induced diabetic rats].

The effect of exercise on leptin in streptozotocin(STZ)-induced diabetic rats was investigated. Four group of SD rats (10 in each group) including exercise STZ diabetic group, non-exercise STZ diabetic group, exercise normal group and non-exercise normal group were used in the study. Exercise groups were treated with treadmill. The results showed that: (1) blood glucose of STZ diabetic rats was higher, serum insulin, C-peptide and leptin level were lower than that of normal rats; (2) blood glucose was decreased, and blood insulin and C-peptide were increased in exercised STZ diabetic group. The levels of leptin in plasma, brain and adipose tissue were increased in exercise groups. It is concluded that appropriate exercise training may have impacts on insulin and leptin production to correct the abnormal glucose metabolism and energy metabolism in diabetic rats.

Animals↗

PubMed2001

[Studies on the inhibitory effects of tea polyphenols and tea pigments on liver precancerous lesion in rats].

The chemopreventive effects of tea polyphenols and tea pigments on liver precancerous lesion in rats were investigated. The results showed that the density and area of GST-P in the tea-treated groups were significantly reduced as compared with the positive control group. Furthermore, tea polyphenols and tea pigments induced the expression of p21WAF1 protein, inhibited the expression of Bcl-2 protein and induced the expression of Bax protein. It is concluded that GST-P was significantly inhibited by tea polyphenols and tea pigments and inhibition of cell proliferation and induction of apoptosis may be the two important mechanisms.

Animals↗

PubMed2001

[Study of deletion and mutation of p16 gene in primary hepatocellular carcinoma].

OBJECTIVE: To investigate the role the deletion and mutation of p16 gene plays in the pathogenesis of human primary hepatocarcinoma. METHODS: Thirty-one cases of human hepatocarcinoma, 31 cases of adjacent noncancerous liver cirrhosis and the leukocytes of 8 normal human subjects were analyzed for deletion and mutation in p16 gene exons 1, 2 and introns 1, 2 with comparative multiple PCR and PCR-SSCP. RESULTS: Deletion of p16 gene exon 1 and partial intron 1 was found in 4 of 31 cases (13/%). No deletion of exon 2 or intron 2 was found. Three patterns of p16 gene intron 1 and 18 bp-flanking sequence in exon 2 at SSCP analysis were observed in hepatocellular carcinoma and corresponding adjacent noncancerous cirrhosis, and two patterns were found in human normal leukocyte DNA. No aberrant single strand at SSCP in p16 gene exon 1 or most part of exon 2 or intron 2 was detected. CONCLUSION: Low frequency of deletion and rare mutation of p16 suppressor gene occurred in hepatocellular carcinoma.

Carcinoma, Hepatocellular↗

PubMed2001

[Serum apolipoprotein A I, B100 and E levels and apolipoprotein E polymorphism in patients with Alzheimer's disease and multiple infarction dementia in Chinese population].

OBJECTIVE: To investigate the relationship of serum apolipoprotein (apo) A I, B100 and E levels and apo E polymorphism to Alzheimer's disease (AD) and multiple infarction dementia (MID) in Chinese population. METHODS: The apoE phenotypes were assayed by isoelectric focusing and immunoblotting, and apolipoproteins were determined by radial immunodiffusion assay in 75 patients with AD, 36 patients with MID and 60 control subjects. RESULTS: The frequency of apo E4 allele (epsilon 4) was significantly higher and the frequency of epsilon 2 allele was lower in AD group, compared with those in the control group (0.2333 vs 0.0666, 0.0467 vs 0.0833, P < 0.05). The frequency of epsilon 4 allele in MID group was also higher than that in the control group (0.2083 vs 0.0666, P < 0.05). The fasting serum apoA 1 and E levels in AD and MID groups were remarkably lower than those in the control group (P < 0.001 and P < 0.05). CONCLUSION: Apo E4 allele epsilon 4 was associated with AD and MID. ApoE4 might be a risk factor for AD and MID, and apo E2 might be a protective factor for AD. The serum apo A I and apoE levels were significantly decreased in patients with Alzheimer's disease and multiple infarction dementia.

Aged↗

PubMed2001

[Factors involved in intelligent development of children with cleft lip and palate].

OBJECTIVE: The objective of this study was to investigate the possible factors involved in intelligent development of children with cleft Lip and palate. METHODS: The intelligence quotient (IQ) and developmental quotient (DQ) of 152 children with cleft lip and palate under 14 years old were conducted, and the control group was made up of 80 healthy children. The considered factors included degrees of deformation, situation of perinatal period, way of feeding, psychological conditions of the children, general situation of their parents and education of these children. The data were statistically analyzed and compared. RESULTS: The IQ value of these children generally was normal, but the mean value was still lower than that of the control group (P < 0.01). The mean IQ value of the group of children with only cleft lip or cleft palate was higher than that of the group with both cleft lip and cleft palate, and the mean IQ value of these children with II degree deformity was higher than that of children with III degree deformity. The mean IQ value of these children feed with mother's milk was higher than that of those feed with artificial milk. These children more than 5 years old were disturbed psychologically, and their parents were also with pressure. CONCLUSION: The intelligent development of children with cleft lip and palate is affected by many factors, including types and degrees of deformity, feeding ways, illnesses and social psychological factors in different periods of development. Therefore, it is very important to take steps before 5 years old, including correctly feeding, repairing the deformity as early as possible, preventing the illnesses, necessary psychological treatment, improving social environment.

Adolescent↗