Biomedical subjects

J Zhao

Publications and source records attributed to J Zhao.

At least 307 records · Page 17Linked to original sources

PubMed2000

[Apoptosis and related gene expression in lacrimal gland of cases with Sjögren's syndrome].

OBJECTIVE: To assess the roles of apoptosis and expression of the related genes in lacrimal glandular destruction of patients with Sjögren's syndrome (SS). METHODS: Small pieces of palpebral lobes of lacrimal glands were obtained from 12 patients (10 with primary Sjögren's syndrome, 2 with secondary Sjögren's syndrome) and 7 normal controls. They had been investigated by the in situ end labeling and immunohistochemical staining to detect the apoptotic cells and the expression of Fas, FasL, bcl-2 and Bax. RESULTS: The number of epithelial apoptotic cells in lacrimal glands of patients with SS was significantly higher than that in normal glands, and SS epithelial cells showed increased expression of Fas, FasL and Bax. There was significant positive correlation between the number of the apoptotic cells and that of the cells expressing Fas, FasL and Bax, respectively, and there was significant negative correlation between the number of the apoptotic cells and that of the cells expressing bcl-2. CONCLUSIONS: The apoptosis of the epithelial cells in the lacrimal gland may be one of the mechanisms leading to the glandular destruction found in SS. In SS lacrimal glands, the expression of Fas, FasL and Bax may promote apoptosis, and the expression of bcl-2 may inhibit apoptosis.

Adolescent↗

PubMed2000

[The effect of three kinds of anti-glaucoma eyedrops on ocular blood flow].

OBJECTIVE: Surveying the changes of ocular blood flow by continuous anti-glaucoma eyedrops for one week. METHODS: Thirty-two patients in glaucoma clinic were divided into three groups, one treated by 0.5% timolol, one by 0.5% levobunolol and the third by 0.1% dipivefrine, twice a day. Each patient got the retinal and choroidal angiography before and after the medication. We also made the intra- and inter-observer reproducibility test for verifying the credibility of the method used to determine the ocular blood flow. All the data were analyzed by Students't test. RESULTS: The reproducibility test revealed this method creditable. Timolol and levobunolol could decrease the choroidal blood flow significantly, there was a trend to decrease the optic nerve blood flow after continues application of timolol eyedrops. Dipivefrine did not induce any significant change on ocular blood flow except the mild artery constriction. CONCLUSION: The results suggest that it is necessary to be careful in choosing the anti-glaucoma eyedrops when ischemia plays an important role in glaucomatous damage.

Adult↗

PubMed2000

[Analysis on Helicobacter pylori infection and its related diseases in 1,442 children in Tianjin city].

OBJECTIVE: The aim of this study was to investigate the prevalence of Helicobacter pylori (Hp) infection in children in Tianjin and to study the relationship between the Hp infection and its related diseases. METHODS: (1) Serologic examination for Hp - IgG; (2) Rapid urease test for Hp (Hp - Rut); (3) Giemsa staining for Hp; (4) Gastric fluid examination for Hp by PCR. Hp infection were diagnosed by at least two criteria. RESULTS: (1) Of the 1 442 children, 651 were Hp - IgG positive. The total positive rate was 45.15%, Positive rates of Hp - IgG among children under the age of 1 year, 3 years, 6 years, 10 years and to 14 years were 11.19%, 19.23%, 44.21%, 54.20% and 61.46%, respectively. (2) Positive rates of Hp - IgG were 31.18% (164/526) and 53.17% (48/916) in asymptomatic children and in patients with gastrointestinal symptoms. The rate was significantly higher in the later group (P < 0.005). (3) Hp infection rate in patients with duodenal ulcer (DU) was 90.76%, higher than that in other gastrointestinal diseases. (4) Histological examination showed that Hp infection rates were 33.20% and 83.97% in mild and moderate or severe gastritis, respectively. CONCLUSIONS: (1) The prevalence of Hp infection in children in Tianjin was high. (2) Rate of Hp infection increased with age and Hp infection rate was higher in children with gastrointestinal symptoms than with asymptomatie. (3) There was a high correlation in children with gastroduodenal diseases and Hp infection especially with DU. (4) Hp positive rate correlated with the pathohistologic severity of gastritis.

Adolescent↗

PubMed2000

[Effects of excessive iodine on activity of enolase in hippocampus of developing mice].

OBJECTIVE: To study the effects of excessive intake of iodine for a long term on activity of enolase in hippocampal tissues of young mice. METHODS: A hyperiodine goiter animal model was replicated with drinking water with high level of iodine. Activity of neuron specific enolase (NSE) in hippocampal tissues was determined with enzyme-linked immunosorbent assay (ELISA) for young offspring of the first and the second generations of mice with hyperiodine goiter on the 7th, 14th and 21st day of age, respectively. RESULTS: Activity of enolase in young offspring of the first and second generation of mice with hyperiodine goiter was all lower than that in controls from the day of their birth to the 30th day after birth, and that at hippocampal tissues in young mice of the second generation was significantly lower than that of the first generation on the 14th day of age. CONCLUSION: Hyperiodine can decrease activity of NSE in the brain of mice. It suggests that hyperiodine can affect NSE, and thus interfere energy supply in the brain, resulting in disturbance of neuron development and brain function.

Animals↗

PubMed2000

[Study on the regulatory effect of Chinese herbal medicine on peritoneal lymphatic stomata and in enhancing drainage of ascites in mice with liver fibrosis].

OBJECTIVE: To observe the regulatory effect of Chinese herbal medicine on peritoneal lymphatic stomata in carbon tetrachloride induced mouse model of liver fibrosis and its significance in treating ascites. METHODS: (1) To form the mouse model of liver fibrosis by intragastric administration of carbon tetrachloride. (2) Two kinds of Chinese herbal compound prescriptions were given separately by gastrogavage to observe their effect on prevention and treatment of liver fibrosis. (3) Hematoxylin and eosin and van Gieson staining were used in the observation of pathology and histology. (4) Scanning electronmicroscope and computer image processing were used. (5) urinary volume and sodium ion concentration were measured. RESULTS: The fibrotic change of the mouse models was alleviated with using both the prevention or treatment groups of the two compound prescriptions. The diameter of lymphatic stomata enlarged with increased number of opening and density of distribution. Urinary volume and sodium ion excretion increased after treatment. The effects displayed more significant in the group treated by compound prescription. CONCLUSION: Both kinds of Chinese herbal compound prescriptions have marked effect in alleviating liver fibrosis, regulating peritoneal lymphatic stomata, improving the drainage from the peritoneal cavity, causing increase of urinary volume and sodium ion excretion to reduce the water and sodium retention, and thus have favorable therapeutic effect in treating ascites.

Animals↗

PubMed2000

[Experimental study on effect of sanmiao mixture capsules on prostate hyperplasia in mice and rats].

OBJECTIVE: To observe the effect of Sanmiao Mixture Capsules(SMC) on prostate hyperplasia in mice and rats. METHOD: The model of prostate hyperplasia was made by injecting testosterone propionate in to male mice(5 g.kg-1.d-1, 21 d) and rats(3 g.kg-1.d-1, 14 d). The treated group was administered SMC(mice: 36.3 g.kg-1 and 18.2 g.kg-1; rats: 25.2 g.kg-1 and 12.6 g.kg-1), the normal control group 1.9 g.kg-1, and the model control group NS. hours after the last administration serum tests were carried out on E2, AKP and Zn2+. Then the animals were killed, prostates taken out and weighed, index of prostate was calculated and pathological examination performed. RESULT: In the SMC treated group, the prostate weight and index were lowered(P < 0.01) the mean activation of E2 was raised, and the mean concentration of AKP and Zn2+ was inhibited (P < 0.01). CONCLUSION: SMC are helpful in checking prostate hyperplasia in mice and rats, the mechanism being probably related to the raising of activation of E2 as well as to the inhibition of concentration of AKP and Zn2+.

Acid Phosphatase↗

PubMed2000

[Changes of lipoprotein lipase and hepatic lipase and their significance in gallstone formation in rabbit model].

This experiment was made to investigate the changes of lipoprotein lipase(LPL) and hepatic lipase (HL) activity and their effects on gallstone formation in rabbit model in which the stones were induced by high cholesterol diet. Activities of plasma LPL and HL were determined; other data including concentration of plasma lipoprotein cholesterol, concentration of bile cholesterol and bile acids were also obtained. The results showed that with the rabbits continuously fed on high cholesterol diet, LPL activity heightened markedly (P < 0.05), and HL activity increased gradually (3 and 4 weeks groups vs control group, P < 0.05). The changes of concentration of plasma VLDL-C and LDL-C were the same as that of LPL activity, but the concentration of plasma HDL-C, HDL2-C, HDL3-C and bile acids showed no significant changes (P > 0.05). These results suggest that the heightened activities of LPL and HL might make the liver take up more cholesterol, secrete it into the bile duct and hence accelerate gallstone formation.

Animals↗

PubMed2000

[Effects of ultrasonography on evaluating the status of cervical lymphatic metastasis in patients with oral squamous cell carcinoma].

OBJECTIVE: To investigate effects of ultrasonography on evaluating the status of cervical lymphatic metastasis in patients with oral squamous cell carcinoma (OSCC). METHODS: Nineteen OSCC patients with the diagnosis confirmed by biopsy of primary focus were included in this study. All the patients were hospitalized in the department of stomatology, Beijing Medical University during June, 1995 and June, 1996, among them there were 13 men and 6 women. The ages were ranged from 31 to 71 years old, with the average of 54.4 years old. The primary focus of 13 cases were in tongue, 3 cases in cheek, 2 cases in gum, and 1 case in the conjunction of gum, mouth floor and tongue respectively. All the patients were examined by ultrasonography prior to operation, and operated with the procedures of excision of primary focus and radical neck dissection. The length, width, Vmax and Vmin and Resistance Index (RI = (Vmax-Vmin)/Vmax) of blood flow of cervical lymphatic nodes were measured with acuson 128 xp/10 color Doppler flow imaging scanner with a 7.5 MHz probe. The total of 34 cervical lymphatic nodes were examined by the scanner. L/W ratios in all nodes, RI and Vmax in 16 nodes were obtained respectively. All results were divided into two groups, metastases and non-metastases groups based on the pathological findings for further statistic analysis. Student t test was employed in the study. RESULTS: The average L/W ratios, the average Vmax and the average RI were 1.95 and 2.17, 0.24 and 0.14, and 0.80 and 0.56 in metastases and non-metastases groups respectively. There was a significant difference between RI in two groups, but no statistical differences were revealed in L/W ratios and Vmax, despite the great difference in the average Vmax in the two groups. When RI > or = 0.65 and Vmax > or = 0.20 m/s were regarded as the criterion for positive diagnosis, the accuracy rate, the sensibility and the specificity was 91.2%, 90%, and 91.7% respectively in making diagnosis of OSCC. CONCLUSION: The status of cervical lymphatic metastases in OSCC patients could be evaluated accurately by the color Doppler flow imaging scanner, which might be helpful in making accurately diagnosis of OSCC, selecting the appropriate operation procedure of neck dissection leading to increased survival ratio and improved quality of life for the patients.

Adult↗

PubMed2000

[Optimal treatment parameters for damage of chicken comb vessels using chlorophyll derivative IV in photodynamic therapy].

OBJECTIVE: To define the optimal treatment parameters of chlorophyll derivative IV (CPD4) in photodynamic therapy(PDT) of port wine stains(PWS) by observing the morphological changes of chicken combs. METHODS: 102 animals were divided into 6 groups at random, including 3 control groups(given no treatment, given light without photosensitizer or given photosensitizer without light) and 3 experimental groups treated with different CPD4 dosages(5, 7.5, 10, 12.5, 15 mg/kg body weight), power density(50, 100, 150, 200 mW/cm2), energy density (15, 30, 45, 60, 120, 135, 180 J/cm2) and different intervals between CPD4 injection and irradiation (immediately, 5, 10, 20, 30, 60, 120, 180, 240 minutes). The main emitting peak of light source was at 650 nm, and CPD4 was injected intravenously, then the appearance of chicken comb was recorded everyday. The prepared sections were stained with HE. The histological changes of chicken comb were observed by light microscope. RESULTS: The control animals showed no significant comb changes, while the PDT could cause blanching of the chicken comb in the experimental group. The histologic changes included damage of erythrocytes and endothelial cells, vascular rupture, hemorrhage or disappearance, denaturation of perivascular collagen fiber and local necrosis of chicken combs. The treatment parameters which caused the most obvious blanching of the chicken comb were 7.5-10 mg/kg body weight of CPD4 dosage, 100-150 mW/cm2 of power density, 60-90 J/cm2 of energy density, and the intervals between CPD4 injection and irradiation were 0-20 minutes. CONCLUSION: CPD4 in PDT can cause selective damage of dermal capillaries in chicken comb and blanching of the chicken comb with optimal treatment parameters. The results will offer the basis for further investigation of clinic treatment parameters.

Animals↗

PubMed2000

[Thyroglossal duct cyst(fistula) operation and recurrence prophylasis].

OBJECTIVE: To explore what leads to recurrent thyroglossal duct cyst (TGDC) following operation and how to improve the operation efficiency. METHOD: 32 patients with TGDC (including 8 recurrent cases) were performed operation for the second time. The cases who had infective signs received anti-inflammatory treatment prior to operation. Judge the relationship between thyroglossal duct cyst and hyoid bone before managing hyoid bone. The methylene blue was injected into TGDC for following up. Resect the small branches according to Sistruk procedure under the operation microscope. The residue underwent marsupiatization, electrocoagulation or radio frequency according to finger palpation. RESULT: 32 cases were successful with the operation and did not show any signs of recurrence after one-year following up. CONCLUSION: The recurrence of TDGC may be perfectly prevented as long as comprehensive treatment is carefully performed during the operation.

Adolescent↗

PubMed2000

[Determination of malignant disease-associated DNA-binding protein 2 in patients with liver cancer].

The aim of this study was to assess the value of malignant disease-associated DNA-binding protein 2(MAD2) in the diagnosis of liver cancer. The concentration of plasma MAD2 was determined in 27 patients with primary liver cancer, 14 patients with metastatic liver cancer and 12 healthy subjects by ELISA assay. The primary tumors of all the patients with metastatic liver cancer were located in the gastrointestinal tract, which had been radically resected and had no signs of local recurrence. The concentrations of plasma MAD2 in the patients with primary liver cancer, with metastatic liver cancer, and the healthy subjects were 30.56 +/- 11.38 micrograms/ml, 9.27 +/- 5.58 micrograms/ml and 8.43 +/- 5.62 micrograms/ml, respectively. The concentration of MAD2 in patients with primary liver cancer was significantly higher than that in the patients with metastatic liver cancer and healthy subjects (P < 0.001). There was no significant difference between the healthy subjects and the patients with metastatic liver cancer(P > 0.05). These results suggest that MAD2 may be an useful marker for the diagnosis of primary liver cancer.

Carcinoma, Hepatocellular↗

PubMed2000

[Study on biodegradation of phenols in river water].

This study on the biodegradation of phenols (phenol, o-methylphenol, o-chlorophenol and resorcinol) in river water was conducted by changing the main influential factors respectively. The results of experiment showed the phenols were greatly degradated in mild temperature, neutral pH and plenty of oxygen and the rank of the phenols biodegradation from great to small was resorcinol, phenol, o-methylphenol and o-chlorophenol. Presented in this paper is also a discussion on the biodegradation mechanism of phenols.

Biodegradation, Environmental↗

PubMed2000

[Effectiveness of recombinant human growth hormone treatment for severe burn injury].

In order to investigate the effectiveness and safety of recombinant human growth hormone(rhGH) treatment for severe burn injury, we designed a randomized prospective study. The patients in rhGH group were given rhGH in a dose of 0.5 IU/(kg.d) subcutaneously between days 3-17 post-burn. Indices about protein metabolism, wound healing, hepatic and renal function and blood were measured regularly. Patients were monitored until their wound healed sufficiently so that they could be discharged for rehabilitation. The results showed: all patients survived; the rhGH group had less weight loss, increased level of serum albumin and shorter healing time of deep partial-thickness burn and donor site. The hospital stay time decreased from the control value of 45 +/- 17 days to 37 +/- 12 days for rhGH treated patients, i.e. a significant improvement. Resistant hyperglycemia was present in 2 patients in the rhGH group and disappeared after transient insulin administration. This study demonstrates that rhGH treatment for severe burn injury has obvious beneficial effects with slight side-effects.

Adult↗

PubMed2000

Regulation effect of vascular endothelial growth factor on human fetal choroid vascularization.

PURPOSE: To investigate the spatial and temporal regulation effect of vascular endothelial growth factor (VEGF) on human fetal choroid vascularization. METHODS: The eyeballs of 54 human fetuses from the 9th week to the 40th week due to accidental abortion were studied by immunohistochemically staining for the expression of VEGF and proliferation cell nuclear antigen (PCNA). RESULTS: (1) The distribution of VEGF expression in the retinal pigment epithelium (RPE) decreased with the increase of age, the peak of which was between the 9th and 14th week. (2) PCNA immunoreactivity was localized within choriocapillaris endothelium. The expression level decreased alone with fetus age. In this period the choriocapillaris endothelium kept proliferation, differentiation, canalization and remodelled to form the choroid vessels. (3) Statistically significant correlations were shown between the expression of VEGF in the PRE and that of PCNA in choriocapillaris endothelium (r = 0.933, P < 0.01). CONCLUSION: VEGF expression in RPE was positively involved in modulating human fetal choroid vascularization.

Cell Differentiation↗

PubMed2000

[Photoluminescent properties of organic film in flat optical microcavity].

The microcavity is sandwiched between a quarterwavelength distributed Bragg reflector(DBR) and a metal Ag reflective mirror. A single layer of a Tris(8-quinolinolato) aluminum (Alq) film was used as the light-emitting layer. The photoluminescent properties of the optical microcavity and that of the Alq film were studied at the same excitation condition. Compared with the Alq film, the significantly narrowed spectral emission linewidth from 90 nm to 10 nm was observed, the PL emission intensity of the microcavity at the resonant mode is enhanced by the order of 1. The spectral narrowing and intensity enhancement of the microcavity is attributed to the microcavity effect.

English Abstract↗

PubMed2000

Micro CT and Micro MR imaging of 3D architecture of animal skeleton.

Quantitative assessment of three-dimensional (3D) trabecular structural characteristics may improve our ability to understand the pathophysiology of osteoporosis, to test the efficacy of pharmaceutical intervention, and to estimate bone biomechanical properties. Considerable progress has been made in advanced imaging techniques for noninvasive and/or nondestructive assessment of 3D trabecular structure and connectivity. Micro computed tomography (microCT) has been used to measure 3D trabecular bone structure in rats, both in vivo and in vitro. It can directly quantify 3D trabecular bone structure such as trabecular volume, trabecular thickness, number, separation, structure model index, degree of anisotropy, and connectivity, in a model-independent manner. We have used microCT to study ovariectomy (OVX) induced osteopenia in rats and its treatment with agents such as estrogen, and sodium fluoride. We have demonstrated that 3D microCT can quantify mouse trabecular and cortical bone structure with an isotropic resolution of 9 microm(3). It is also useful for studying osteoporosis in mice and in phenotypes of transgenic mice or gene knockout mice. MicroCT can be used to quantify osteogenesis in mouse Ilizarov leg lengthening procedures, to quantify osteoconduction in a rat cranial defect model, and to quantify cortical bone porosity. Recently, microCT using high intensity and tight collimation synchrotron radiation to achieve spatial resolution of 1-2 microm has provided the capability to assess additional features such as resorption cavities. Unlike microCT, micro magnetic resonance imaging (IMRI) is nonionizing. Recently, the ability of microMRI to assess osteoporosis in animal models has been explored. Using a small, high-efficiency coil in a high-field imager, microMRI can give resolutions sufficient to discriminate individual trabeculae. We have shown that, with appropriate settings, it is possible to image trabecular bone in rats in vivo and in vitro. In our study of OVX rats, analysis of microMR images can demonstrate differences in rat trabecular bone that are not detected by DXA measurements. In a rabbit OA model, with the OA induced by meniscectomy or anterior cruciate ligament transection, MRI shows decreased cartilage thickness, subchondral osteosclerosis and osteophytes, while radiographs can only show subchondral osteosclerosis and osteophytes could not be found. Advanced imaging methods are able to measure 3D trabecular structure and connectivity in arbitrary orientations in a highly automated, objective, non-user-specific manner, allowing greater numbers of samples for unbiased comparisons between controls and the disordered or treated. They can be utilized on a large sample leading to fewer sampling errors. They are non-destructive allowing multiple tests such as biomechanical testing and chemical analysis on the same sample; and non-invasive permitting longitudinal studies and reducing the number of animals needed.

Journal Article↗

PubMed1999

Purification and cloning of amyloid precursor protein beta-secretase from human brain.

Proteolytic processing of the amyloid precursor protein (APP) generates amyloid beta (Abeta) peptide, which is thought to be causal for the pathology and subsequent cognitive decline in Alzheimer's disease. Cleavage by beta-secretase at the amino terminus of the Abeta peptide sequence, between residues 671 and 672 of APP, leads to the generation and extracellular release of beta-cleaved soluble APP, and a corresponding cell-associated carboxy-terminal fragment. Cleavage of the C-terminal fragment by gamma-secretase(s) leads to the formation of Abeta. The pathogenic mutation K670M671-->N670L671 at the beta-secretase cleavage site in APP, which was discovered in a Swedish family with familial Alzheimer's disease, leads to increased beta-secretase cleavage of the mutant substrate. Here we describe a membrane-bound enzyme activity that cleaves full-length APP at the beta-secretase cleavage site, and find it to be the predominant beta-cleavage activity in human brain. We have purified this enzyme activity to homogeneity from human brain using a new substrate analogue inhibitor of the enzyme activity, and show that the purified enzyme has all the properties predicted for beta-secretase. Cloning and expression of the enzyme reveals that human brain beta-secretase is a new membrane-bound aspartic proteinase.

Amino Acid Sequence↗

PubMed1999

Inhibition of human carcinoma cell growth and DNA synthesis by silibinin, an active constituent of milk thistle: comparison with silymarin.

Several studies from our laboratory have shown the cancer chemopreventive and anti-carcinogenic effects of silymarin, a flavonoid antioxidant isolated from milk thistle, in long-term tumorigenesis models and in human prostate, breast and cervical carcinoma cells. Since silymarin is composed mainly of silibinin with small amounts of other stereoisomers of silibinin, in the present communication, studies were performed to assess whether the cancer preventive and anti-carcinogenic effects of silymarin are due to its major component silibinin. Treatment of different prostate, breast, and cervical human carcinoma cells with silibinin resulted in a highly significant inhibition of both cell growth and DNA synthesis in a time-dependent manner with large loss of cell viability only in case of cervical carcinoma cells. When compared with silymarin, these effects of silibinin were consistent and comparable in terms of cell growth and DNA synthesis inhibition, and loss of cell viability. Based on the comparable results of silibinin and silymarin, we suggest that the cancer chemopreventive and anti-carcinogenic effects of silymarin reported earlier are due to the main constituent silibinin.

Antineoplastic Agents, Phytogenic↗