[Progress in the study of tissue engineering of bone and cartilage].
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Biomedical Engineering↗
Biomedical subjects
Q Zhang
Publications and source records attributed to Q Zhang.
[Effect of plumular axis-cutted cotton on growth and development of cotton bollworm].
The method of plumular axis cutting was used to induce the resistance of cotton plants to cotton bollworms(Heliothis armigera). The bollworm was cultured in the laboratory, and the effect of induced cotton on the duration of larval development and weights of larvae and pupae was studied. In the treatments of infection and control, the lengths of larval period were delayed by 3 days and 0.5 days, the weights of larvae were decreased by 19.60% and 11.45%, and the pupae weights were decreased by 10.81% and 6.54%, respectively. After the 8 days old larvae were reared with induced cotton leaves for 3 days, the infected and uninfected cutted plants resulted in a decrease of the relative growth rates of larvae by 22.9% and 17.2% respectively, and in a decrease of the relative feeding rates by 26.1% and 21.4% respectively. It is suggested that plumular axis cutting could induce the resistance of cotton plants to bollworm, and influence the growth and development speed of bollworms through retarding their feeding and digestion. Combining with the treatment of Pseudomona gladioli D-2251 strain could obviously increase the insect-resistance of cotton plants.
Animals↗
[Relationship between isometric exercise and myocardial ischemia in patients with coronary artery disease: an Echo-Doppler study].
OBJECTIVE: To study the relationship between isometric exercise and myocardial ischemia in patients with coronary artery disease (CAD). METHODS: Twenty CAD patients and 10 normal subjects were included in our study. All subjects performed maximal brief isometric exercise (BIE), maximal sustained isometric exercise (SIE) and dynamic exercise (DE). Hemodynamic parameters and cardiac function were measured by Echo-Doppler technique. To avoid influence of different baseline values, increment (delta%) of exercise response was used as parameter for significant analysis: delta% = (exercise values - baseline values)/baseline values x 100%. RESULTS: Positive exercise testing (PET) showed no evidence of myocardial ischemia during BIE and SIE even though their rates of perceived exertion (RPE) were similar to DE. delta% heart rate (HR) and delta% rate pressure product (RPP) were higher during DE than during SIE and BIE in negative exercise testing (NET) and normal controls (NOR) (P < 0.01), except PET during DE and SIE; delta% systolic blood pressure (SBP) was higher during DE than during BIE in NOR (P < 0.01). delta% SBP in NOR and NET during SIE was higher than during BIE (P < 0.05). delta% diastolic blood pressure (DBP) was the highest during SIE among exercises in all gropus (P < 0.05). There were no significant inter-group differences of delta% HR, delta% SBP, delta% DBP and delta% RPP during SIE, BIE and DE, except that delta% SBP during SIE was higher in NET than in NOR and PET (P < 0.05). In NOR, delta% ejection fraction (EF), delta% fractional shortening of the minor-semi axis (SF), delta% cardiac output (CO), delta% E/A was higher during DE than during SIE and BIE (P < 0.01). delta% stroke volume (SV) was similar during DE, SIE and BIE. There were no significant differences in delta% EF, delta% SF, delta% CO, delta% SV and delta% E/A during DE, SIE and BIE in both NET and PET, except lower delta% CO in NET during SIE and BIE than DE (P < 0.01). There were no inter-group differences in delta% EF, delta% SF, delta% CO and delta% E/A, except that delta% E/A was higher during SIE in NET than PET (P < 0.01). During DE, NOR and NET had higher delta% SV, delta% SF, delta% CO and delta% E/A than PET (P < 0.05). CONCLUSIONS: The incidence of myocardial ischemia in CAD patients was lower during isometric exercise than dynamic exercise at similar perceived exertion levels. Isometric exercise might protect the myocardium from ischemia through high coronary artery perfusion pressure and long perfusion duration. We suggest that application of isometric exercise in a cardiac rehabilitation program may have reasonable physiological background.
Aged↗
[Effect of melatonin on the spatial and temporal changes of [Ca2+]i in single living cells of cortical neurons by laser scanning confocal microscopy].
OBJECTIVE: To examine the effects of melatonin on the dynamic changes in the concentration of intracellular free Ca2+ ([Ca2+]i) in single intact cultured cortical neurons isolated from fetal rats, in order to explore the possible antiaging mechanisms of melatonin (MT). METHODS: Using the highly fluorescent Ca(2+)-sensitive indicator Fluo-3/AM, cortical neurons cultured in a 35 mm Tissue Culture Dish were in incubated for 45 min at room temperature with 5 mumol/L Fluo-3/AM, resulting in proper intracellular dye concentration to provide adequate signal strength for detection and excellent Laser Scanning Confocal Microscopy (LSCM) imaging of [Ca2+]i while not disturbing normal intracellular physiology. The changes in fluorescent intensity were monitored by LSCM. RESULTS: Bay K8644 (10(-6) mol/L), KCl (20 mmol/L), sodium L-glutamate (Glu, 50 mumol/L) caused a rapid increase of [Ca2+]i in cortical neurons, and this increase could be significantly attenuated by 10(-6) and 10(-7) mol/L MT. CONCLUSIONS: MT could antagonize the extracellular Ca2+ influx, reduce Ca2+ overload, and have a protective effect on neurons. This may be one of the important antiaging mechanisms of MT.
Aging↗
Screening for mt-DNA mutations in optic neuritis of unknown cause.
OBJECTIVE: To investigate mitochondrial DNA (mt-DNA) mutations in optic neuritis of unknown cause (ONUC) and to assess the practical value of mt-DNA mutation detection in etiologically and differentially diagnosing ONUC. METHODS: Thirty patients with ONUC were screened for mt-DNA mutations of nt11778, nt3460 and nt15257 by using SSCP, mutation-specific primer PCR and sequencing. RESULTS: mt-DNA mutations were found in twelve of thirty ONUC patients. All of the mutations were at nt11778 position, but no one at nt3460 and nt15257. CONCLUSIONS: Forty percent (12/30) of ONUC patients were caused by an mt-DNA mutation. Combined with other routine measures, screening for mt-DNA mutations in ONUC patients is of great significance in diagnosing ONUC etiologically and differentially.
Adolescent↗
Comparison of computer-photoscreening with non-cycloplegic retinoscopy for amblyopiogenic risk factors in children.
OBJECTIVE: To determine the sensitivity and specificity of using a computer-photoscreener and non-cycloplegic retinoscopy in the detection of amblyopiogenic factors in nine to fifty months old infants and children. METHODS: Three hundred children, nine to fifty months old, were screened with the computer-photoscreener and non-cycloplegic retinoscopy. With a blinded standardized clinical assessment as the standard, an overall comparison of the sensitivity of and specificity results obtained with the two techniques was made. Photoscreen images on the computer monitor screen were reviewed and analyzed immediately by two independent observers for indicators of amblyopiogenic risk factors. Simultaneously, the results were compared to the findings of a full ophthalmologic examination. RESULTS: The computer-photoscreener revealed a sensitivity of 94.6% and specificity of 90.1%, and the non-cycloplegic retinocopy revealed a sensitivity of 85.7% and specificity of 81.0% for the detection of amblyopiogenic risk factors, including hyperopia (+2.75 D or more), myopia (-1.50 D or more), astigmatism (1.75 D or more), anisometropia (2.00 D or more), ocular misalignment (5 degrees or more), and media opacity (1.5 mm or more). CONCLUSIONS: The computer-photoscreener offers an opportunity to identify problems that limit vision, and could provide a feasible and sufficiently reliable screening technique in infants and preschool children to be screened successfully for amblyopiogenic risk factors.
Amblyopia↗
[Mechanisms of drug resistance of primary renal cell carcinomas and their clinical significance].
OBJECTIVE: By multifactorial analysis, to study the mechanisms of drug resistance of primary renal cell carcinomas (RCC). METHODS: Seventy cases of paraffin-embedded RCC tissue sections were examined for the expression of P-gp, GST-pi and Topo II by immunohistochemical staining. RESULTS: There was 65.7% of RCC with expressed P-gp. Its Expression was stronger in late than in early stage of RCC. GST-pi was expressed in 41.1% RCC, but the magnitude of expression did not correlate with differentiation, type and stage of RCC. All the RCC examined had Topo II expression. Its expression level was lower than that of cancer of the intestine and lung. Among the 70 cases of RCC, 31.4% of them expressed at least one of the 3 drug-resistance parameters. Co-expression of two drug-resistance parameters was observed in 42.8% of the cases that of 3 drug-resistauce parameters in 22.9% of the cases. CONCLUSION: Drug resistance is of common occurrence in RCC. To achieve better therapeutic efficacy, appropriate chemotherapeutic agents should be given to patients with low expression of P-gp and GST-pi but high expression of Topo II.
ATP Binding Cassette Transporter, Subfamily B, Mem↗
[Experimental study on effect of bushen yijing recipe in delaying senility of bone and brain of aged male rats].
OBJECTIVE: To evaluate the effect of Bushen Yijing recipe (BSYJR) in delaying senility of bone and brain of aged male rats and infer its mechanism in delaying systemic senility. METHODS: Forty male SD rats, 24 months old were randomly divided into 4 groups, the baseline control group, the aged control group (30 months old), the BSYJR high dose group and the BSYJR low dose group. The latter two groups received BSYJR treatment from 24 months old to 30 months old. Bone indexes (bone density of the proximal, middle and distal segments of left femur and break bending load of right femur) and brain indexes (binding capacity of M receptor and cholinesterase activity of brain) were measured after responding treatment. RESULTS: In bone, BSYJR could not only increase the bone mineral density in various segments of femur, but also raise the bending break load of femur dose-effect dependently. In brain, BSYJR could both up-regulate the binding capacity of M receptor and inhibit the activity of cholinesterase. CONCLUSION: BSYJR could delay the senility of bone and brain in male rats, inferring that it might regulate integrally the abnormality of aging in Kidney Asthenia and Essence Deficiency through mediation of nerve-endocrine-immunity network.
Aging↗
["Three steps procedure" in the treatment of large pancreatic head cancer].
OBJECTIVE: To evaluate the feasibility and effectivity of "3 steps procedure" in the treatment of large pancreatic head cancer. METHODS: The "3 steps procedure" consisted of decompression of jaundice by simple cholecystotomy, intervenient (intra-arterial) chemotherapy (5-FU 1 approximately 1.5 g, mitomycin 8 approximately 14 mg, cisplatin 40 approximately 60 mg and octreatide 1 mu intravenously as near the superior and inferior pancreatic-duodenal arteries as possible), and then the reasonable regional pancreatic-duodenectomy. RESULTS: All 16 tumors were radically resected. Conventional and regional pancreatic-duodenectomy was done in 7 and 9 patients, respectively; of the later group, artificial prosthesis for portal vein bridge was done in 3 patients, end-to-end anastomosis in 4 and repair after partial resection of invaded vessel wall in 2. CONCLUSION: The "3 steps procedure" is feasible and effective in the treatment of large pancreatic head cancer.
Adult↗
[Protective effect of Ginaton on rat liver microcirculation disturbance following liver xenotransplantation].
OBJECTIVE: To study the effect of Ginaton on liver microcirculation disturbance following liver xenotransplantation in rats. METHODS: Ginaton was injected intravenously to recipients at a dosage of 14 mg/kg before graftng liver of guinea pigs. The portal blood flow (PBF) was measured by Doppler ultrasound at 0, 30 and 60 minutes after transplantation, and the pathologic changes of liver and heart were observed. RESULTS: The reperfusion status of control group was poor and leukocyte infiltration appeared in the center of lobute following transplantation and myocardial cells were impaired. Significant reduction in PBF was found in rats following transplantation. Ginaton pretreatment distinctly ameliorated PBF. The speed of PBF was closely correlated with the pathologic changes following transplantation. CONCLUSION: In the process of liver transplantation, ischemia reperfusion damage may lead to xenoheptic microcirculaton disturbance. Ginaton could improve the xenoheptic microcirculation and reduce ischemic reperfusion damage.
Animals↗
[Adenosine in treatment of rats with spinal cord injury].
OBJECTIVE: To observe the changes of endogenous extracellular adenosine after spinal cord injury (SCI) to rats and the effect of exogenous adenosine on extracellular calcium after SCI and post-injury neurological function. METHODS: A ventral compression injury model of T13 spinal cord was used, and the extracellular fluids were collected consecutively every 20 minutes after injury by using microdialysis. Adenosine in the samples was analyzed using high-pressure liquid chromatography (HPLC) with u.v. detection. The rats received different doses of 2-chloroadenosine (2-CADO), a nonspecific agonist of adenosine receptors, by intrathecal injection 15 minutes before injury. The extracellular fluid was collected every 10 minutes immediately after injury and the calcium was measured using atomic absorption spectrophotometer. Neurological function score, inclined plane angle, and histology were observed 24 hours after injury. RESULTS: A significant increase of adenosine was found immediately after spinal cord injury. The concentration of adenosine peaked at one hour after injury and dropped down to the basal level. There was a positive relation between the increase of adenosine and the severity of SCI. High dose of 2-CADO can significantly significantly inhibit the decrease of extracellular calcium and improve the neurological function of injured rats. CONCLUSIONS: Adenosine could involve the pathological process of secondary spinal cord injury and might play a protective role in SCI.
2-Chloroadenosine↗
[Long-term results of combined therapy for primary osteosarcoma in extremities].
OBJECTIVE: To evaluate the survival rates, functional outcome, and complications between the combined and non-combined treatment of primary osteosarcoma of the extremities. METHOD: From 1977 through 1992, 170 patients with high-graded, nonmetastatic osteosarcoma were treated. Their average age at diagnosis was 21 years old (ranging from 6 to 52). Tumors were observed at distal femurs in 80 patients (47%), proximal tibia in 51 (30%), proximal humors in 10 and other locations in 22. Combined therapy (en bloc resection of tumor with preoperative and postoperative neoadjuvant chemotherapy) was given 104 patients and non-combined therapy (tumor resection only) to 66. Ninety-four patients underwent limb salvage surgery. In 76 patients who received amputations or disarticulations 33 received chemotherapy. RESULTS: The 5-and 10-year-survival rates were 61% and 53% in the combined therapy group and 28% and 26% in the non-combined therapy group. Local recurrence rate was 23% in limb salvage surgery group and 5.2% in amputation group. Functional evaluation of 80 patients showed that the patients who underwent salvage surgery had higher functional scores than those who had an amputation according to MSTS scoring system (1993). The average scores reached 71% in the salvage surgery group and 53% in the amputation group. CONCLUSIONS: In this study, long-term that combined therapy raised the survival rate of the patients with osteosarcoma. The ase of en bloc resection of bone tumor and reconstructive technique, has enable limb salvage procedures possible to produce excellent functional outcomes. The patients who well have responses to preoperative chemotherapy may have a higher survival rate.
Adolescent↗
[Time course of TGF beta 1 and VEGF expression in experimental vein grafts].
OBJECTIVE: To investigate time course of TGF beta(1) and VEGF expression and their role in intimal hyperplasia. METHODS: In situ hybridization and immunohistochemical technique were used to detect the time course of intimal hyperplasia, time course of TGF beta(1) mRNA and protein expression of TGF beta(1) and VEGF. RESULTS: After autogenous vein replacement, the obvious neointima was seen at 2 weeks, and peaked at 8 weeks. The expression of TGF beta(1) mRNA peaked at 1 week and decreased gradually, but at 10 weeks, its positive cell percentage was still 10.1%. Both protein expression of TGF beta(1) and VEGF in VSMCs increased from 24 hours after grafting and peaked at 2 weeks. Their positive cell percentages were 40.6% and 36.6% respectively. After 4 weeks, their expression decreased at 8 weeks, the positive cell percentages were 8.9% and 13.8% respectively. CONCLUSIONS: TGF beta(1) plays an important part in ECM accumulation by promoting ECM synthesis and decreasing ECM degradation. VEGF plays the key role in reendothelialization. They may affect each other and cooperated in the formation of intimal hyperplasia.
Animals↗
[Telangiectatic osteosarcoma: report of 10 cases].
OBJECTIVE: To raise the level of early diagnosis of telangiectatic osteosarcoma (TOS). METHODS: Ten patients with TOS were treated from July 1991 to December 1998. The patients included men 6 and 4 women, aged from 4 to 44 years (average 23.7 years). The lesions were located at the proximal femur (1 patient), distal femur metaphysis (2), femur shaft (1), proximal tibia metaphysis (2), distal tibia (1) and humerus shaft (3). Preoperative pathologic examination showed two cases of TOS by open biopsy(negative by needle biopsy); the rest were found negative (2 patients), metastasis (1), and sarcoma (5) by needle biopsy. Eight patients received preoperative chemotherapy. Operations including limb-salvage (3) and amputation (7) were performed in all patients. All patients accepted postoperative chemotherapy. RESULTS: 10 Follow-up for a mean of 28 months (range 6 - 72 months) showed no local recurrences: disease-free in 4 patients and pulmonary metastasis in, 6, of whom 5 died and 1 is still alive with lung metastasis. CONCLUSION: TOS is often misdiagnosed and needs early diagnosis and correct treatment under the cooperation of clinicians, radiologists and pathologists.
Adolescent↗
[Cloning and identifying of renal cell carcinoma differentially expressed genes].
OBJECTIVE: To clone and identify RCC specially expressed genes different with normal kidney tissue. METHODS: A technique called suppression subtractive hybridization was used to construct the library which contains the differently expressing cDNAs between RCC and normal kidney. Then the RCC specially expressed genes were cloned from it. RESULTS: Human RCC subtractive library with high subtractive efficiency was set up successfully. The amplified library contains 350 positive clones. Sequence analysis was performed in 5 clones. All of the sequences were unknown before and the cDNA inserting GYLZ-RCC18 had three copies. Northern blot analysis showed that GYLZ-RCC18 cDNA expressed highly in RCC, but there was no any signal could be detected in normal kidney. Using SMART RACE technique, we obtained the full length of novel gene of GYLZ-RCC18. We also identified that GYLZ-RCC18 family contains 3 subtype genes. CONCLUSIONS: The highly efficient cDNA subtractive library lays a solid foundation for screening and cloning new and specific oncogenes or tumor suppressor genes of RCC. The novel differentially expressed genes provide an important clue to studying the mechanism of the occurrence and development of RCC.
Carcinoma, Renal Cell↗
[Analysis of postoperative astigmatism after phacoemulsification with intraocular lens implantation].
OBJECTIVE: To study the corneal astigmatism and the changes of surgically induced astigmatism after phacoemulsification with intraocular lens (IOL) implantation. METHODS: Thirty-eight eyes of 38 patients treated with phacoemulsification through a superior inversed frown shaped scleral incision were examined by corneal topography and auto-ref-keratometer preoperatively, one day, one month and three months postoperatively. RESULTS: The postoperative corneal astigmatism at one day, one month and three months were (1.10 +/- 0.71), (1.08 +/- 0.66) and (0.87 +/- 0.55) D respectively. There was no statistic significance between the postoperative astigmatism at three months and at preoperative one day (P > 0.05). The mean surgically-induced astigmatism at postoperative one day, one month and three months were (1.37 +/- 1.03), (1.24 +/- 0.93) and (1.04 +/- 0.75) D respectively. There was significant difference between the astigmatism at three months and at one day postoperatively (P < 0.05). CONCLUSIONS: The superior inversed frown shaped scleral small incision with no suture has little effect on corneal astigmatism. Vector analysis can systemically evaluate surgically induced astigmatism. The results of corneal topography are more reliable to reflect changes in corneal curvature than that of auto-ref-keratometer, and corneal topography has more important clinical value in evaluating surgically induced astigmatism.
Astigmatism↗
[Detection of numerical chromosome aberrations in sperm of workers exposed to benzene series by two-color fluorescence in situ hybridization].
OBJECTIVE: To study the numerical aberrations of sex chromosomes in sperm of workers exposed to benzene series. METHODS: The interphase sperm from workers of exposed and control groups were hybridized using two color fluorescence in situ hybridization with X and Y(alpha)-satellite chromosome specific DNA probes, and the aneuploidy frequencies of X and Y chromosome in X and Y sperms were detected simultaneously. RESULTS: Geometric mean concentration of benzene in workplace air was 83.95 mg/m(3), one fold higher than national maximum allowable concentration. A total of 74,517 sperm nuclei in 13 benzene-exposed workers and 89,662 sperm nuclei in 13 control workers were counted. Frequencies of disomic sperm for X, Y and XY were (0.15 +/- 0.05)%, (0.13 +/- 0.05)% and (0.20 +/- 0.11)% in workers exposed to benzene series, and (0.10 +/- 0.04)%, (0.10 +/- 0.04)% and (0.13 +/- 0.06)% in control workers. There was statistical difference in disomic frequency of X sperm and overall disomic frequency between the benzene series-exposed workers (0.15% and 0.48%, respectively) and the control workers (0.10% and 0.33%, respectively). CONCLUSION: Exposed to benzene at higher concentration may induce increase in aneuploidy frequency of sperm sex chromosome in exposed workers.
Adult↗
[The prevention of primary liver cancer by selenium in high risk populations].
OBJECTIVE: To study the preventive effects of selenium on primary liver cancer. METHODS: After screening of blood samples in 18,000 males from 20 to 65 years-old in Qidong, Jiangsu province (a high risk area for liver cancer), 2,065 cases of HBsAg positive, AFP negative and normal liver function (normal ALT values) were found. The subjects were randomly divided into two groups, based on their residence areas; 1,112 subjects (experimental group) received one tablet of sodium selenite (0.5 mg Se) every day and 953 subjects (control group) received one placebo tablet every day. RESULTS: During three years of intervention and follow up, the blood selenium concentration and glutathione peroxidase activity of the subjects in the experimental group were increased and had significant difference as compared with those of the control group (P < 0.01). At the same time, the prevalence rate of micronucleus cells in peripheral blood lymphocytes in the experimental group was significantly lower than that of the control group (P < 0.01), and the incidence of new liver cancer in the experimental group (3 057.55/10(6), 34 cases out of 1,112 subjects) was significantly lower than the control group (5 981.11/10(6); 57 cases out of 953 subjects) (P < 0.01). CONCLUSION: The results confirms that selenium supplementation in general populations lived in high risk is effective in the prevention of liver cancer and the using of selenium tablets is simple and feasible.
Adult↗