Biomedical subjects

J Chen

Publications and source records attributed to J Chen.

At least 1,027 records · Page 57Linked to original sources

PubMed2000

[Correlation between epidermal growth factor receptor messenger RNA expression and the onset of labor].

OBJECTIVE: To study the correlation between epidermal growth factor receptor messenger RNA expression and the onset of labor. METHOD: Semiquantitative reverse transcriptase polymerase chain reaction, using GAPDH as internal standard, was applied to determine the levels of epidermal growth factor receptor messenger RNA in human myometrium (n = 20) and fetal membranes (n = 20) before and during labor. RESULTS: In myometrium, epidermal growth factor receptor messenger RNA increased from 0.91 +/- 0.32 before labor to 1.33 +/- 0.23 after the onset of labor (P < 0.05). In fetal membranes, epidermal growth factor receptor messenger RNA increased from 1.05 +/- 0.30 before labor to 1.65 +/- 0.71 after the onset of labor (P < 0.05). CONCLUSION: The study indicates it is Up-regulation of epidermal growth factor receptors messenger RNA expression in myometrium and fetal membrane before and after the onset of labor.

Amnion↗

PubMed2000

[Non-cirrhotic portal hypertension associated with autoimmune disease].

OBJECTIVE: To summarize the cases of non-cirrhotic portal hypertension associated with autoimmune disease, review the literature and introduce the clinical and pathological features of the syndrome. METHODS: Six female patients treated, between 1983 and 1998 had no history of hepatitis. Variceal bleeding occurred in 5 patients. One patient received sclerotherapy and operation was performed in 3 patients for variceal bleeding. Four patients were subjected to liver biopsy. RESULTS: Liver dysfunction of these patients remained normal and variceal bleeding didn't reccur after therapy. Liver biopsy showed nodular regenerative hyperplasia without fibrous septa. CONCLUSIONS: Non-cirrhotic portal hypertension associated with autoimmune disease is a rare syndrome, characterized by significant portal hypertension as well as histological evidence that cirrhosis is absent. Prevention and treatment of variceal bleeding is very important.

Adult↗

PubMed2000

[The attractive effects of nerve regeneration chamber fluid and degenerated nerve segments on the growth and the migration of the cocultured dorsal root ganglion neuron].

OBJECTIVES: We intended in this study to investigate the neurotropic effects of regeneration chamber fluid (RCF) and the degenerated nerve segments from distal of the regeneration chamber on the dorsal root ganglion (DRG). METHODS: The capillary model was first tested for its reliability to form concentration gradient with a dye being contained in the capillaries. The tissue culture in RCF test was divided into two groups each with 8 DRGs implanted in 8 dishes. RCF was contained in capillaries inserted down to the bottom of the dishes with their lower ends at a distance of about 1 mm to the DRGs in the experimental group, and DMEM media was contained in the control group. Segments of degenerated sciatic nerve from distal of the regeneration chamber were implanted with DRGs at a distance of about 0.5 - 1 mm in the coculturing experiment. DRGs were observed for the direction of the growth of the cells and the fibres. RESULTS: While the capillary containing the dye was put down to the bottom of the culture dish coated with a piece of nylon pad, the red color slowly disseminated with heavier staining in the center and lighter staining in the peripheral portion. We believe this pattern of shade could simulate the concentration gradient of tropic factors in this model. There were significantly more nerve fibres growing from the DRGs towards the capillaries in 6 of the 8 dishes in the experimental group after 72 hours of culture. The tissue and nerve fibers grew evenly in the control group. 76.5% of all the nerve fibres were growing in the direction facing the degenerated nerve segments after 12 hours of coculturing, and only 33.3% of the nerve fibres growing in that direction in the control group. Cells from the DRGs migrated towards the degenerated nerve segments, yet they tended to avoid the normal nerve segments. The migration index of the cells was 0.98 in average in the coculturing experiment with the degenerated nerve segments, but only 0.43 in average with the normal nerve coculturing. CONCLUSION: The capillary model was effective in studying the chemotactic growth of nerve tissue. RCF and the degenerated nerve segments had definite neurotropic effects on DRGs tissue.

Animals↗

PubMed2000

[Adjustable interatrial communication in management of severe congenital heart disease].

OBJECTIVE: To assess the use of adjustable interatrial communication in patient with severe congenital heart disease undergoing open heart surgery. METHODS: From February 1998 to June 1999, 13 patients with severe and complex congenital heart disease underwent open heart surgery. Seven patients underwent total cavopulmonary connection, five patients repair of Ebstein's anomaly, and one patient right atrial-pulmonary connection. Adjustable interatrial communication was made in all patients. Four patients had the communication closed at the time of operation, 4 patients had the communication opened at the time of operation, and 5 patients had the communication adjusted and closed postoperatively. RESULTS: All patients had a smooth postoperative process. There were no postoperative death and no severe postoperative complications. CONCLUSION: Adjustable interatrial communication for the patients undergoing modified Fontan procedure or correction of Ebstein's anomaly may be advantageous.

Adolescent↗

PubMed2000

[Xanthogranulomatous pyelonephritis].

OBJECTIVE: To study the diagnosis and treatment of xanthogranulomatous pyelonephritis (XGP). METHOD: The clinical characteristics, diagnosis and therapy of 28 cases of XGP were discussed. RESULTS: The clinical characteristics of XGP included: calculi or obstruction in urinary tract, and damage to kidney; complication of urinary tract infection; anemia, increased ESR and dysfunction of liver. 13 patients with XGP were diagnosed before operation. Nephrectomy was performed in 20 patients. Kidneys were preserved in 8 patients. All patients recovered after operation. CONCLUSIONS: The clinical characteristics and image of XGP are good to preoperative diagnosis. They are useful to differentiate XGP from renal carcinoma and other renal infectious disease. Surgery and antimicrobial are important to XGP. Nephrectomy might be done in patients of stage III kidney may be preserved in patients of stage I and stage II.

Adolescent↗

PubMed2000

[The effects of platelet-derived growth factor-AA on the osteoclasts].

OBJECTIVE: To study the effects of platelet-derived growth factor (PDGF)-AA on the osteoclasts. METHODS: The PDGF receptor alpha (PDGFR-alpha) was detected on the osteoclastic membrane with immunoelectronmicroscopy. Acid phosphatase (ACP) and tartrate-resistant acid phosphatase (TRAP) activities were measured kinetically and the introcellular hydrogen ions were calculated on the confocal laser scanning microscope (CLSM) stained with SNAFL. Stained by toluidine blue, the area and number of the resorption pits were determined with the Leica Quantimet 500 system. RESULTS: The colloidal gold precipitated on the cellular membrane, and the TRAP activity had no difference (P > 0.05). Hydrogen ions rose significantly but their release could not be promoted by PDGF-AA. The changes of the resorption pits were not significant. CONCLUSIONS: The PDGF-AA could promote hydrogen ions yielding but not stimulate osteoclastic bone resorption due to the significant TRAP changes of TRAP activities.

Acid Phosphatase↗

PubMed2000

[Relationship between new TNM classification and the prognosis and biological behavior of gastric cancer].

OBJECTIVE: To determine the clinical value of 1997 TNM classification of gastric cancer. METHODS: 334 cases of gastric cancer with regional lymph node metastasis were used to determine the relationship between new TNM classification and the prognosis and biological behavior compared with old classification (1987). RESULTS: The 5-year survival rates of the old pN(1), pN(2) were 49.6% and 33.5% respectively; those of the new pN(1), pN(2), pN(3) were 48.5%, 24.1% and 5.6% respectively. There was a highly significant difference in survival in different new pN groups (P < 0.01). The new pN classification was correlated with the depth of cancer invasion, as well as the macroscopic type, growth pattern and serosal type (P < 0.01). Multivariate COX model analysis showed that the new pN classification was the most significant independent prognostic factor. CONCLUSIONS: The new TNM classification is not only an objective, simple and reproducible system, but also a significant prognostic index for gastric cancer superior to the old classification.

Adult↗

PubMed2000

[Expression of Fas ligand on peritumoral lymphocytes and its association with apoptosis of colorectal carcinomas].

OBJECTIVE: To study the expression of Fas ligand on peritumoral lymphocytes and its relation to the apoptosis of colorectal carcinoma. METHODS: The expression of Fas protein and FasL in 86 cases of colorectal carcinomas and normal colorectal tissues at the margins of resection was studied immunohistochemically. Apoptosis of cancer cells was evaluated with TUNEL method, which was then correlated with FasL expression on peritumoral lymphocytes. RESULTS: 53 (61.6%) of 86 cases of colorectal carcinoma were stained positively with Fas monoclonal antibodies, but such stain was net found in the normal colorectal tissues at the margin of resection. Peritumoral lymphocytes of 69 cases (80.2%) were stained positively with FasL antibodies. The intensity of FasL staining on peritumoral lymphocytes was positively correlated with the apoptotic index of cancer cells in the Fas positive colorectal carcinomas (P < 0.01), but not in the Fas negative group. CONCLUSION: FasL expressed on the surfaces of peritumoral lymphocytes mediates apoptosis of colorectal cancer cells by acting on its receptor, Fas protein on cancer cells. The elevation of Fas expression on cancer cells and application of specific Fas antibodies may serve as new approaches to treat colorectal carcinoma.

Adult↗

PubMed2000

[Clinical and pathological characteristics of gastric stump cancer and recurrent gastric stump cancer].

OBJECTIVE: To study early diagnosis and rational treatment of gastric stump cancer and recurrent gastric stump cancer. METHODS: The data of 27 patients with gastric stump cancer and 23 patients with recurrent gastric stump cancer were analysed retrospectively during the past 20 years based on their clinical and pathological findings. RESULTS: The onset time was 10 years or more for gastric stump cancer and less than 10 years for recurrent gastric stump cancer after gastrectomy. Gastroscopy was better than double contrast radiography in diagnosis. Partial resection of gastric stump was performed for patients with early cancer at the anastomotic stoma of gastrojejunostomy. Total resection of gastric stump was made for other patients. Lymph node of the mesojejunum were dissected routinely because their metastasis rate was about 40.0% in patients with cancer of anastomotic stoma. The effect of surgical treatment was poor for patients with advanced cancer. CONCLUSIONS: Regular gastroscopy is useful in detecting gastric stump cancer in patients with gastric cancer after gastrectomy, or in those years after removal benign. Malignancy was more evident in recurrent gastric stump cancer than in primary gastric cancer. Prognosis is good for early stage cases and poor for late stage cases after surgical treatment.

Adult↗

PubMed2000

[Mitogenesis of platelet-derived growth factors to human osteoblasts modulated by basic fibroblast growth factor].

OBJECTIVES: To investigate the mechanism by which basic fibroblast growth factor modulates the mitogenesis of platelet-derived growth factor to human osteoblasts. METHODS: The osteoblasts isolated from human fetal calvaria were incubated with PDGF-AB (100 ng/ml) or bFGF(10 ng/ml) combined with PDGF-AB (100 ng/ml); the growth curve was plotted. The(3)H-TdR incorporation of the osteoblasts was measured after the cells were incubated with different combination of bFGF and PDGF-AA or PDGF-BB. After incubated with bFGF (10 ng/ml) for 24 hours, the number of PDGFR-alpha and PDGFR-beta on the membrane of the osteoblasts was detected by fluoroimmunoassay. RESULTS: Four days after PDGF-AB added into the medium, the population of the osteoblasts was larger than that of the control (P < 0.05). The number of the osteoblasts incubated with PDGF-AB (12.1 x 10(4)) was 1.8 times as large as the control (6.8 x 10(4)) in the 10th day (P < 0.05), and that of the osteoblasts incubated with both bFGF and PDGF-AB increased more quickly than the cells only incubated with PDGF-AB. The incorporation of (3)H-TdR into the osteoblasts cultured with bFGF combined with PDGF-AA (533.6 +/- 13.1) was more than that cultured only with PDGF-AA (435.4 +/- 14.8, P < 0.01), so was the incorporation of (3)H-TdR of those cells cultured with bFGF and then PDGF-AA (633.8 +/- 51.5). bFGF up-regulated PDGFR-alpha and down-regulated PDGFR-beta on the surface of the human osteoblasts. CONCLUSION: bFGF elevates the mitogenesis of PDGF-AA or -AB to human osteoblasts by up-regulating PDGFR-alpha.

Cell Proliferation↗

PubMed2000

[Sentinel lymph node biopsy in breast cancer: value for predicting the status of axillary node].

OBJECTIVE: To evaluate feasibility and accuracy of intraoperative lymphatic mapping with sentinel lymphadenectomy (SLND) for predicting axillary status in patients with breast cancer. METHODS: Our study enrolled 52 patients with primary breast cancer, clinically and ultrasonographically negative axillae. Mapping procedures and SLND were performed using methylene blue injected at the primary breast cancer site followed by axillary lymph node dissection (ALND). Sentinel node (SN) was examined by using frozen sections intraoperatively and all of the axillary lymph nodes were evaluated pathologically (HE) after operation. RESULTS: Sentinel nodes were identified in 46 (88.5%) of 52 procedures and nodal status accurately predicted axillary in 44 (95.7%) of 46 cases. In 2 (4.3%) of 46 cases, the SN was false-negative. The overall sensitivity of the SN technique was 90.9%, with a specificity of 100%. The overall positive and negative predictive values were 100% and 92.3%, respectively. In 15 (75%) of 20 cases of clinically negatively and pathologically positive axillary, the SN was the only tumor-involved lymph node identified. CONCLUSION: Our study indicates that intraoperative lymphatic mapping using a vital dye and SLND can accurately predict the axillary status of primary breast cancer patients with clinically and ultrasonographically negative axillae.

Adult↗

PubMed2000

[Thoracolumbar injuries: pathomorphology of and a new classification].

OBJECTIVE: To introduce a new classification of thoracolumbar injuries. METHODS: Three modes were used to classify the injuries according to the mechanisms of injuries: Type A, flexion-compression fractures; Type B, vertical compression fractures; Type C, distraction injuries. Two groups were used to distinguish the fractures in one type according to the pathomorphological differences and the clinical incidence: Group A, with a more clinical incidence, and Group B, with a less clinical incidence. Three subgroups were used to divide the injuries in one group in consideration of the severity of the fracture instability and the fracture displacement: fracture, subluxation, and dislocation. RESULTS: A new classification of thoracolumbar fractures was established. CONCLUSION: The new classification is more systemic and more convenient.

Humans↗

PubMed2000

[Anterior interbody autografting and internal fixation for primary surgical management of thoracolumbar spinal tuberculosis].

OBJECTIVES: To verify the importance of early reconstruction of spinal stability and to evaluate the safety of anterior instrumentation in surgical management of spinal tuberculosis. METHODS: Eleven cases of thoracolumbar spinal tuberculosis were treated with primary anterior debridement, interbody autografting and Z-plate fixation from October 1997 to January 1999. RESULTS: All the 11 cases healed without any recurrence after follow-up for an average of 16 months. Spinal fusion occurred in 3.8 months on average after surgery. 18 degrees of kyphosis correction was achieved with no associated complication. CONCLUSIONS: Early reconstruction of spinal stability plays an important role in surgical management of spinal tuberculosis, and it is safe to implant anterior titanium spinal instrument in tuberculosis foci.

Adolescent↗

PubMed2000

[A clinical study on fresh amniotic membrane transplantation for treatment of severe ocular surface disorders at acute inflammatory and cicatricial stage].

OBJECTIVE: To investigate the safety and evaluate the effect of fresh amniotic membrane transplantation to reconstruct the ocular surface with severe inflammation and scarring. METHOD: Amniotic membrane transplantation (38 cases, 46 eyes), or combined with either limbal transplantation (9 cases, 9 eyes) or lamellar keratoplasty (8 cases, 8 eyes) was performed on ocular surface burns (5 cases, 6 eyes), recurrent Mooren's ulcer (8 cases, 8 eyes) and severe symblepharon (38 cases, 46 eyes). All the patients were followed-up for 6 - 18 months (mean, 11 months). Impression cytology was examined in 21 eyes with normal tear secretion post-operatively. RESULTS: No acute rejection was observed after fresh amniotic membrane transplantation. No progressive melt and perforation were seen in five out of six eyes with burns in reconstructed ocular surfaces. Neovascularization, pseudopterygium and iris atrophy were not found during the follow-up. Visual acuity was improved in various degrees. Corneal ulceration was not noted in 8 cases (8 eyes) with frequently recurrent Mooren's ulcer. Ocular surface reconstruction was successful in 46 of 49 eyes with severe symblepharon. Symblepharon occurred in the remaining three eyes but much less than pre-transplantation in degree. Amniotic epithelia have been examined in about three months on the transplanted eyes with normal tear secretion. CONCLUSION: Fresh amniotic membrane can be used as a graft to reconstruct ocular surface. Such transplantation can effectively reduce neovascularization, fibrosis and inflammation. Our data indicated that complete removal of pathological tissues and perfect fixation of amniotic membrane graft are crucial steps in the reconstruction of ocular surface.

Acute Disease↗

PubMed2000

[Immunologic experimental studies on the alkali burn of cornea in rats].

OBJECTIVE: To investigate the immune reaction of severe corneal alkali burns. METHODS: The models of severe corneal alkali burns were induced in rats. Immunohistochemistry was carried out on wholemounts of the cornea and iris at different time points after corneal burns to detect T-lymphocytes and their subpopulation, macrophages, dendritic cells and MHC class II -positive cells. RESULTS: In the early stage of the burns, there were small increasing number of T-lymphocytes and MHC class II-positive cells in the cornea and iris. At the period of corneal melting and perforation, a massive influx of lymphocytes (CD(+)(3), CD(+)(4), CD(+)(8)), macrophages and dendritic cells was seen in the cornea adjacent to the limbus and iris. CD(+)(4) lymphocytes were much more than CD(+)(8) in number. T-cells and MHC class II-positive cells were observed not only at the limbus but also in the melting area and corneal center. Morphological changes of these cells were also noted. In the restoration stage, a number of positive cells were still found in the iris. CONCLUSION: Immunological mechanism is involved in the pathological changes of the damage induced by corneal alkali burns, especially in the pathogenesis of the corneal melting and perforation.

Alkalies↗

PubMed2000

[Multiple patterns of angle closure mechanisms in primary angle closure glaucoma in Chinese].

OBJECTIVE: The mechanism of primary angle closure glaucoma (PACG) in Chinese is studied to establish a new classification system based on the etiology and mechanism of angle closure. METHODS: The anterior chamber angle's configuration and the anatomic structures related to the angle in 126 cases with PACG were observed with ultrasound biomicroscope (UBM), and the mechanisms of angle closure were analyzed by diagnostic treatment. RESULTS: Based on the configuration of the angle and anatomic structures related to the angle as well as the mechanisms of angle closure, PACG could be divided into following subtypes: pure pupillary block angle closure glaucoma [PPB, 48 cases (38.1%)]; pure non-pupillary angle closure glaucoma [PNP, 9 cases (7.1%)]; multiple mechanism angle closure glaucoma [MM, 69 cases (54.8%)]. PPB manifested that the relative position of pupillary margin was located anteriorly, the peripheral iris bombé was due to the pupillary block, and the angle closure was not related to the location and shape of the peripheral iris and ciliary body. PNP showed that the relative position of pupil margin was located posteriorly, the angle closure was not caused by the pupillary block, but caused by anterior located ciliary body and/or thick and anterior located peripheral iris. MM pattern was caused by both pupillary block and non-pupilary block, and most of the cases manifested creeping angle closure. CONCLUSIONS: The angle closure mechanisms of PACG in Chinese are of multiple patterns. Based on the different mechanisms of angle closure in PACG, a new classification system should be established to improve the diagnosis and treatment of PACG.

Adult↗

PubMed2000

[The survey of HIV prevalence among drug users in Guangxi, China].

OBJECTIVE: To understand the distribution and related risk factors of HIV infection among drug users in Guangxi. METHOD: Three hundred and twenty five drug users were tested for serum HIV antibody, with enzyme linked immunosorbent assay. RESULTS: One hundred and sixteen drug users (35.7%) were found to be HIV positive. The main risk factors associated with HIV infection were intravenous drug users and needle sharing among drug users. The HIV prevalence was 40.9% (114/279) among IDUs, and only 4.3% (2/46) among oral drug users. The phenomenon of sharing injecting equipment (76.7%) among intravenous drug users in Guangxi represents a very serious problem. CONCLUSION: There is a high risk of HIV infection among drug users in Guangxi. Prevention programs urgently need to be implemented.

Adolescent↗

PubMed2000

[Primary study on immunologic effect of live attenuated hepatitis A vaccine (H2 strain) after booster dose].

OBJECTIVE: To study the immunologic effect of live attenuated hepatitis A vaccine (H(2) Strain, 10(7.0)TCID(50)) after booster and to compare with the results of 1 dose live attenuated hepatitis A vaccine (H(2) Strain, 10(7.0)TCID(50)). METHODS: 42 susceptibles with negative anti - HAV were selected in Zhengding, Hebei province. Each subject received 3 doses live attenuated hepatitis A vaccine at 0, 2, 6 months and was bled at 1, 2, 6, 7, 9, 12 months after vaccination. RESULTS: The seroconversion rate at 1 month after the first dose was 81.4% and reached 100% after the second dose. GMT arrived the peak 2,739 mIU/ml at one month after the third dose, before stared declining. The seroconversion rate kept 100% at 12 months after the first dose, but GMT decreased to 979 mIU/ml. CONCLUSION: The first dose worked as the base of boostering. A booster dose of live attenuated hepatitis A vaccine could induce secondary immune response well. The immunologic effect after booster dose could match the effect with inactivated vaccine and was better than the results of 1 dose live attenuated hepatitis A vaccine. The program seemed to be useful to the protective effect and the immuno - persistence.

Child↗