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Biomedical subjects

C Chen

Publications and source records attributed to C Chen.

At least 523 records · Page 29Linked to original sources

[The main schools of TCM in Zhejiang].

The history of the main academic TCM schools is described, beginning from Danxi school of Zhu Zhenheng of the Yuan dynasty to the 1980s. Established the theory of "exuberant yang and insufficient yin", Zhu set up the therapy of nourishing yin to decrease fire. In the late Ming dynasty, Zhao Xianke and Zhing Jingyue founded the warm - tonification school, Zhao's theory on vital gate exerted profound influence on the basic theory of later ages. At the turn of Ming - Qing dynasties, a Qiantang school was set up by Zhang Shuichen, Zhang Zhicong and Zhang Xijun, Zhang Zhi cong being the synthetizen. The Shao school of cold-disease refers mainly to the physicians in the shaoxin region who studied the warm heat disorders (especially damp - warm diseases) which was mature at the turn of Qing dynasty and the Republican period, whose influence remained until the 1980s.

China↗

Serum leptin levels and adiposity in adult Chinese: a preliminary observation.

OBJECTIVE: To establish normal serum leptin levels in Chinese and investigate the relationship between serum leptin levels and body fat, gender, age and androgen. METHODS: Serum leptin levels were measured in 77 lean (BMI < 25) and 28 overweight or obese (BMI > or = 25) subjects by a radioimmunoassay (RIA) method. RESULTS: The serum leptin levels in lean Chinese were 2.15 +/- 1.46 ng/ml in male and 7.85 +/- 3.60 ng/ml in female, which are similar to those of Caucasians, while in overweight or obese ones, the levels were 4.87 +/- 3.47 ng/ml and 16.59 +/- 6.92 ng/ml respectively, lower than those in Caucasians. A 2-3 times higher leptin concentrations were found in women than in men in both conditions. Even when the number of lean males was expanded to 79 subjects aged from 17-80 years, no significant leptin-age relationship was found. Despite 25% of obese subjects manifested a relative deficiency of leptin, as a whole, leptin levels in both men and women were significantly correlated with BMI (r = 0.69, P < 0.001 in male and r = 0.63, P < 0.001 in female). CONCLUSIONS: Serum leptin levels in Chinese lean people are similar to those in Caucasians and in both lean and obese groups, the leptin levels are correlated with BMI, suggesting that the great majority of the obese patients are resistant to endogenous leptin. Those who are relatively deficient of leptin may become a group of good candidates for leptin treatment in the future.

Adult↗

A study of platelet organelles and membrane glycoprotein in patients with Binswanger's disease.

OBJECTIVE: To discuss the possible role of platelets in Binswanger's disease by studying the changes of organelles and membrane glycoprotein in platelets. METHODS: The organelles (dense bodies, alpha granules, and mitochondria) within platelets were measured with transmission electron microscopy in 25 patients with Binswanger's disease and matched controls, while alpha granule membrane glycoprotein CD62 and lysosomal integral membrane glycoprotein CD63 on platelet membrane were analyzed by flow cytometry. RESULTS: The percentage of CD62-positive platelets was 3.6% +/- 2.1% and 5.7% +/- 2.4% in controls and in patients, respectively (P < 0.01). The percentage of CD63 expression platelets was 3.1% +/- 2.2% and 3.2% +/- 2.3% in controls and patients, respectively (P > 0.05). When compared with controls, platelets of patients contained fewer alpha granules (P < 0.01), and had no changes in dense bodies and mitochondria (P > 0.05). CD62 levels were different among patients with regarding to the degree of white matter low attenuation. CONCLUSION: There is selective degranuation of platelets in patients with Binswanger's disease and the abnormalities of platelet secretion may play a role in the pathophysiology of this illness.

Aged↗

[The study of E-cadherin expression on injury and repair of epithelium of respiratory tract in smoking mice].

OBJECTIVE: To investigate effects of smoking on E-cadherin (E-cd) expression of injury and repair of respiratory tract epithelium by observation of dynamic expression of E-cd on epithelial cells of respiratory tract in smoking mice. METHODS: Immunohistochemistry SP technique was used to examine E-cd expression on epithelial cells of respiratory tract in smoking mice of different stages and dosages and the morphological changes observed by light and electron microscopy respectively. RESULTS: Four and twelve weeks after smoking, the E-cd expression in the epithelial cells was significantly down-regulated compared with the control group (P < 0.01). Morphologically, the intercellular junction was loose, and the epithelial cells were injured and proliferated on the same time. Eight weeks after smoking, however, the E-cd expression was not different from that of the control group (P > 0.05). CONCLUSIONS: Smoking is able to cause wavy change of the E-cd expression on the epithelial cells which may play an important role in the injury and repair of the epithelial cell of the respiratory tract.

Animals↗

[Dynamic effect of the blood glucose and insulin on serum leptin concentration during oral glucose tolerance test].

OBJECTIVE: To investigate the effects of internal change of plasma glucose and serum insulin levels on serum leptin concentrations during oral glucose tolerance test (OGTT) in normal subjects and type II diabetics (DM). METHODS: Plasma glucose, serum insulin and leptin concentrations were measured simultaneously in 50 age, sex and body mass index matched non-diabetic (non-DM) and 50 DM subjects who were undergoing OGTT. RESULTS: The fast serum leptin concentrations were (3.88 +/- 0.64) microg/L in DM males and (8.30 +/- 1.06) microg/L in DM females. Respectively they were (5.01 +/- 0.64) microg/L and (10.48 +/- 1.30) microg/L in non-DM group. No significant difference was revealed. Comparing with the non-DM group, the glucose curve was elevated and the insulin releasing curve was characterized by a low response and a delayed peak in DM group. As for the leptin releasing curve, both groups showed a decreasing trend, which seemed to be more evident in DM group. CONCLUSION: Leptin concentration does not increase with the release of insulin. On the contrary, it shows a diurnal rhythmic descending trend, suggesting that in vivo, the insulin effect on serum leptin concentration is relatively weak and not able to affect the day-time descending trend of leptin levels.

Blood Glucose↗

[Spontaneous renal rupture].

OBJECTIVE: To study clinical regularity of spontaneous renal rupture. METHODS: 16 cases of this disease were reviewed. Renal carcinoma was found in 4, angiomyolipoma in 2, undetermined etiology in 3, and invasive colic cancer, kidney cyst, nephrolithiasis, SLE with nephritis, polycythemia vera, renal tuberculosis, portal hypertension in 1 each. RESULTS: CT demonstrated a sensitivity of 87.5% in identifying the underlying kidney mass, which was higher than that (25%) of B-type ultrasound and (0) KUB + IVU. Radical nephrectomy was carried out in 6 cases, renal-reserved operation in 5, and conservative treatment in 5. CONCLUSIONS: 60% of spontaneous renal rupture are due to kidney neoplasia. CT scanning is the most valuable diagnostic procedure. If the primary cause has not been clarified, close follow-up with periodic CT scanning might be mandatory.

Adult↗

[Piezoelectric, electrohydraulic and electromagnetic shock wave lithotripsy for lower ureteral stone].

OBJECTIVE: To treat patients with lower ureteral stones by extracorporeal shock wave lithotripsy (ESWL) using piezoelectric, electrohydraulic and electromagnetic second lithotriptors. METHODS: Six hundred and three patients were divided into 3 groups according to the modes of lithotriptors. There were 179 patients in EDAP LTO1 piezoelectric group, 294 in JDPN IV electrohydraulic group and 130 in Dornier Compact S electromagnetic group. Every group was further divided into 3 subgroups with 10 mm, 10 - 15 mm and 15 mm in diameters of stones. RESULTS: The stone-free rate in single session of ESWL was higher in the electromagnetic group than in the other two groups. The efficiency quotient was lower in piezoelectric group than in the electrohydraulic and electromagnetic groups. The stone-free rate in single session was achieved in more than 70% of stones less than 15 mm in diameter for electromagnetic and electrohydraulic ESWL. CONCLUSIONS: The overall results of electromagnetic and electrohydraulic ESWL on lower ureteral stones are better than those of piezoelectric ESWL, and ESWL is suitable for stone less than 15 mm in diameter.

Adolescent↗

[Extracorporeal shock wave lithotripsy in situ for middle ureteral stones].

OBJECTIVE: To report the experience with in situ ESWL for patients with middle ureteral stones. METHODS: 52 patients suffering from stones with an average 11 mm (range 5 - 20 mm) in dimension were treated using modified Puigvert technique in prone position via the entry route of lateral abdomen. The patients received 3,000 - 5,000 shocks per session at the power setting ranged from 2 to 7. RESULTS: The stone free rate at 3 months was achieved in 96% patients retreatment was performed in 30% patients. The therapeutic results were calculated as efficiency quotient being 74%. No severe complications occurred in all patients. CONCLUSIONS: In situ ESWL for middle ureteral stone is safe and effective and may serve as the first line therapy.

Adult↗

[The expression of MTS1 gene product in transitional mucosa adjacent to rectal carcinomas and its clinical significance].

OBJECTIVE: To study the property of transitional mucosa (TM) adjacent to rectal carcinoma and the clinical significance of MTS1 gene deficit. METHODS: We used the immunohistochemical methods to observe the range of TM adjacent to rectal carcinoma, and the immunohistochemical method to observe the expression of MTS1 gene product on TM, using normal mucosa and carcinoma tissue as control. RESULTS: The positive expression level of MTS1 gene product was the highest in the normal rectal mucosa, gradually defective in TM and carcinoma tissue (P < 0.05). The range of TM with MTS1 negative cases was prominently larger than that with MTS1 positive cases (P < 0.05). CONCLUSIONS: The inactivation of MTS1 gene is relative to the occurrence of rectal carcinoma, suggesting that the TM adjacent to rectal carcinoma possess as certain potential malignancy. TM is related to MTS1 gene expression deficit of rectal carcinoma, showing that MTS1 gene expression deficit or mutation may be a factor inducing transitional change adjacent to carcinoma.

Adult↗

[Histopathology studies on 8,673 cases of ocular adnexal hyperplastic lesions and tumors].

OBJECTIVE: To study the histopathologic classification of ocular adnexal hyperplastic lesions and tumors according to the histogenesis and the anatomic sites. METHOD: To analyze retrospectively the pathologic specimens of 8,673 cases of ocular adnexal hyperplastic lesions and tumors between 1961 - 1997. RESULTS: There were 7,265 benign cases (83.77%), and 1,408 malignant cases (16.23%). Classification by anatomic sites: eye lid 5,313 cases (61.26%), orbit 1,484 cases (17.11%) and epibulbar 1,876 cases (21.63%). Classification by histogenesis: (1) Primary tumor 6,679 cases: epitheliogenic 2,481 cases (37.15%), mesenchymal 753 cases (11.27%), lympho-hematopoietic 102 cases (1.53%), neurogenic 1,542 cases (23.09%), congenital abnormal embryogenetic 1,767 cases (26.46%), uncertain resource tumor 34 cases (0.50%). (2) Secondary tumor 13 cases; (3) Metastatic tumor 9 cases; (4) Non-tumor lesion 1,972 cases. CONCLUSION: The classification is helpful to the histopathologic diagnosis and the study about the detailed distribution of common ocular adnexal hyperplastic lesions and rare tumors, and it also increases the pathologic diagnostic data in North China.

Eyelid Neoplasms↗

[Studies on male reproductive toxicity caused by hexavalent chromium].

OBJECTIVE: To study male reproductive toxicity caused by hexavalent chromium (Cr(VI +)). METHODS: Morphology of semen and spermatozoa was observed and chromium level in blood, chromium and zinc level in sperm plasma, leuteinizing hormone (LH) and follicle stimulating hormone (FSH) levels in serum were determined for male workers exposed to (Cr(VI +)) (CrO(3)X = 0.0195 mg/m(3)) with occupational epidemiologic investigation and laboratory analysis. RESULTS: For the exposed workers, their seminal counting was (52.21 +/- 45.51) x 10(9)/L, and zinc level in seminal plasma (4,811.85 +/- 1,401.88) micromol/L, significantly lower than those in controls (88.96 +/- 74.82) x 10(9)/L and (5 718.49 +/- 2 827.90) micromol/L, respectively, P < 0.05. Serum FSH was (7.34 +/- 6.88) IU/L in the exposed groups, significantly higher than that of controls (2.41 +/- 1.69) IU/L, P < 0.01. There were no significant difference in semen volume, semen liquefaction time, prevalence of teratospermia, serum Cr(VI +) and LH level in seminal plasma between exposed group and control group (P > 0.05). Prevalence of teratospermia was 0.24 +/- 0.09, and serum LH and FSH were (7.94 +/- 2.67) IU/L and FSH (9.33 +/- 6.47) IU/L, respectively, in workers exposed to high concentration of Cr(VI +) (CrO(3)X = 0.2351 mg/m(3)) significantly higher than those exposed to lower concentration of Cr(VI +) (CrO(3)X = 0.0172 mg/m(3)), with 0.17 +/- 0.06 of prevalence of teratospermia, (5.05 +/- 3.05) IU/L of LH, and (3.74 +/- 3.04) IU/L of FSH, respectively (P < 0.05). CONCLUSION: The results suggested that damage to convoluted seminiferous tubules epithelium, reduction of spermatozoa formation and increase in prevalence of teratospermia could be caused by exposure to certain concentration of Cr(VI +).

Adult↗

[Studies on pharmacological junctions of hairy root of Astragalus membranaceus].

OBJECTIVE: To investigate the effect of hairy root of Astragalus membranaceus(HRA). METHOD: HRA were given 10 g/kg per day for 50 days to aged mice treated with D-galactose, and the effect on memory and antioxidant functions were estimated. After administration of HRA 10 g/kg for four days, anti-ischemia-reperfusion kidney model of rat was prepared. The kidney function, activity of superoxide dismutase (SOD) and content of malondialdehyde(MDA) in kidney were examined. Mice with immunosuppression induced by cyclophosphamide were given orally HRA 10 g/kg for 12 days. The activity of natural killer (NK) cells was measured. RESULT: HRA improved the memory, raised SOD activity in brain and liver, decreased the MDA content in the liver of aged mice, reduced the MDA content in ischemia-reperfusion kidney, decreased the creatinine level in blood of rats, and promoted the activity of NK cells in immunosuppressed mice. CONCLUSION: Similar to the natural A. membranaceus, HRA has senility-preventing, antioxidizing and immunomodulating functions.

Aging↗

[Comparative study on livertaxis of lactosaminated human growth hormone and galactosyl-human growth hormone].

This study was conducted to compare the livertaxis of lactosaminated human growth hormone (hGH-L) with that of galactosyl human growth hormone (hGH-Gal), using radioactive tracer technique. hGH-L and hGH-Gal were first prepared. After hGH-L, hGH-Gal and hGH were labelled with 131I or 125I, the data on biodistribution in mice, imaging in rabbits and chicken were obtained. hGH-L and hGH-Gal had remarkable livertaxis and their percentages for uptake in liver were 68.83%-74.65% and 68.18%-74% respectively, which were about two times as high as that of hGH. All of the hepatic bindings were receptor-mediated. But, the synthesizing of hGH-L was more easy-to-do, more mild in reaction conditions, and more economical of raw material as compared with the synthesizing of hGH-Gal. Therefore, hGH-L is a more potential receptor-mediated hepatic targeting secreting somatomedian drug for treating dwarfism.

Animals↗

[Two-dimensional finite element analysis for morphology of craniofacial hard tissue of people with anterior crossbite at early permanent dentition].

OBJECTIVE: To analyze the morphology of craniofacial hard tissue of people with anterior crossbite at early at early permanent dentition. METHODS: The craniofacial morphology of hard tissue of 80 cases anterior crossbite of the early permanent dentition was analyzed by a special computer software system for finite element analysis of two-dimensional cranio-facial structure. RESULTS: The size change of each element was smaller than shape change in cross-bite group, which suggested that the shape change was the main element change; The posterior cranial base was found abnormal in both male and female groups, with counterclockwise rotation occurring at posterior cranial base to some extent; The upper part of face and the maxillary suffered underdevelopment in both male and female groups; The most outstanding change in size and shape occurred at anterior and superior part of mental, with each component of counterclockwise rotation to varying degree. CONCLUSION: Abnormality that occurs in craniofacial hard tissue of people with anterior crossbite at early permanent dentition period is highlighted by abnormal skeletal shape change and rotation, and may be one of the fundamental factors causing crossbite.

Adolescent↗

[The study of ethanol-water used as reversed-phase high performance liquid chromatographic mobile phase].

The viscosity of ethanol-water at various temperatures was determined. The physicochemical properties and characters of the solvents used as the mobile phase of reversed-phase high performance liquid chromatography(RP-HPLC) were compared between methanol and ethanol. The components of several Chinese medicines have been determined by RP-HPLC with ethanol-water used as mobile phase, and the results were compared with those obtained with methanol-water or acetonitrile-water. It showed that ethanol can be used as RP-HPLC mobile phase by increasing the column temperature moderately.

Chromatography, High Pressure Liquid↗

[Effect of triclabendazole on the ultrastructure of body wall and vitelline cells of Paragonimus westermani].

AIM: To observe the ultrastructural changes in the body wall and the vitelline cells of Paragonimus westermani in vitro and in vivo before and after triclabendazole treatment. METHODS: The worms were obtained from in vitro and in vivo tests. All of the samples were processed by conventional techniques, and observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). RESULTS: The external plasma membrane and matrix were cracked or disappeared after the treatment. The necrosis of the muscular layer differed. The cell membranes of cortex and vitelline cells were damaged. Nuclear membrane was damaged partially, heterochromatin solidified and condensed to brim and dissolved. The Golgi complex disappeared, endoplasmic reticulum expanded, mitochodria denatured and dissolved. The damage was more serious in vivo than in vitro. CONCLUSION: Triclabendazole is remarkablely effective against Paragonimus westermani by damaging the body wall and vitelline cells, mainly affecting the nuclei, membrane structures and microtubular system.

Animals↗

[The protective effect against Toxoplasma infection in mice immunized with laser-irradiated Toxoplasma tachyzoites].

AIM: To observe the level of immune responses and protective immunity in mice induced by laser-irradiated Toxoplasma tachyzoites (LIT). METHODS: ICR mice were immunized with LIT. After one month, the mice were challenged with live Toxoplasma tachyzoites to observe the effect of LIT. Indirect immunofluorescence assay and ELISA were used to detect CD4+/CD8+ lymphocyte subpopulation and IgG antibody. RESULTS: Immunization with LIT could partially protect the mice from Toxoplasma infection, prolong the survival time, enhance the CD4+/CD8+ ratio and produce specific IgG antibody. CONCLUSION: Intraperitoneal injection with LIT can induce partial protective immunity and specifically elicit ICR mice to generate humoral and cell-mediated immune responses.

Animals↗