Biomedical subjects

M Zhang

Publications and source records attributed to M Zhang.

At least 397 records · Page 22Linked to original sources

PubMed2000

[Establishment of a Hantaan virus infected mouse neuron cell model].

OBJECTIVE: To establish a neuron cells model for Hantaan virus (HTNV) infection by using the cultures of cortical neurons of mouse embryo. Changes and mechanism of the damage in neurons after HTNV infection were studied. METHODS: The cortical neurons of 16-19 day old mouse embryo were cultured and infected with HTNV (A9 strain). Indirect immunofluorescence test (IFT), MTT colorimetric analysis and immunohistochemistry assay (IHCA) were used to detect immunofluorescent antibody reaction of neurons, growth and development of the neurons. RESULTS: In neurons of HTNV infected mouse embryo, continually cultured for one week, lFT antigen was detected positive, the activity of the infected neurons was reduced obviously and the growth of neurons was obstructed. CONCLUSIONS: Direct infection of HTNV on the cultured neurons was identified, indicating that mouse embryonic critical neurons is one of the sensitive target cells for HTNV infection.

Animals↗

PubMed2000

[Evaluation of plant protectants against pest insects].

An interference index of population control (IIPC) was constructed for investigating the complex effects of plant protectants, including the effects of repelling insect pests away from the plant, deterring the egg laying of adults and the continuation of feeding, and causing death by toxicity. At the same time, indicated by IIPC, the alcohol extracts of some common plants, such as Eucalytus rubusta, Wedelia chinensis etc. and the neem oil gave very good results to protect the plant against Plutella xylostella. The D-C-Tron NR Petroleum Spray Oil (CALTEX) also gave an excellent effect to protect citrus against red mite. All the experiments show the important role of the repellent effect on the pests.

Animals↗

PubMed2000

Recombinant bovine basic fibroblast growth factor accelerates wound healing in patients with burns, donor sites and chronic dermal ulcers.

OBJECTIVE: To evaluate the effect of recombinant bovine basic fibroblast growth factor (rbFGF) on accelerating healing of burn wounds, donor sites and chronic dermal ulcers in multicenters. METHODS: One thousand and twenty-four patients with burns, donor sites and chronic dermal ulcers were recruited for this prospective and multicenter clinical trial and another 641 patients with the similar wounds were used as controls. All patients were divided into three groups: burn group, donor site group, and chronic dermal ulcer group. In the burn group, 654 patients with superficial second-degree burns(superficial II degree) or deep second-degree burns(deep II degree) were treated topically with either recombinant bovine basic fibroblast growth factor (rbFGF plus vehicle, rbFGF 150 AU/cm2/day, 330 patients) or placebo (vehicle without rbFGF, 324 patients). In the donor site group, 509 patients were treated with rbFGF and 317 patients with placebo in a similar way as described elsewhere. In the chronic dermal ulcer group, 185 patients were treated with rbFGF and the controls were themselves. Photography, histological evaluation and clinical examination were used to evaluate the results of wound healing. RESULTS: All of superficial second-degree burns, deep second-degree burns and the donor sites treated with recombinant bovine basic fibroblast growth factor had an accelerated rate of granulation tissue formation and epidermal regeneration as compared with that in the controls. Superficial second-degree burns and deep second-degree burns treated with recombinant bovine basic fibroblast growth factor healed in 9.89 +/- 2.45 and 17.04 +/- 4.56 days, respectively, whereas the average healing time in those receiving placebo was 12.35 +/- 2.74 and 21.21 +/- 4.88 days. The donor sites treated with rbFGF or placebo healed in 10.68 +/- 4.55 and 14.74 +/- 6.46 days, respectively. All chronic dermal ulcers except 12 patients treated with rbFGF healed within 6 weeks. Histological evaluation of punch-biopsy specimens from the burn wounds, donor sites and chronic dermal ulcers seven days after treatment supported the impression of accelerated wound healing after rbFGF treatment. CONCLUSIONS: rbFGF is effective in shortening the wound healing time and improving the wound healing quality. Accelerating wound healing is of clinical benefit in reducing the length of hospitalization, costs and emotional burden of the patient.

Adolescent↗

PubMed2000

Co-modification of IL-2-TNF alpha fusion gene and B7.1 gene to murine breast tumor cells leads to improved tumor rejection and vaccine effect.

OBJECTIVE: To improve the vaccine potency of gene-modified tumor cells. METHODS: Using recombinant adenoviruses, we expressed the B7.1 gene in murine breast tumor cell line EMF6 and a subline previously transfected with retrovirus vector XdF harboring the IL-2-TNF alpha fusion gene. RESULTS: Immunization/challenge experiments demonstrated that IL-2-TNF alpha/B7.1 co-modified tumor cells possessed a lower tumorigenicity in vivo and an improved tumor-specific vaccine potency compared with single gene transfectant (P < 0.05). Three weeks after immunization with a variety of tumor cells, the mixed lymphocyte and tumor cells reaction assay (MLTB) and 51Cr-release assay were performed to test cellular immunity function. The results indicated that IL-2-TNF alpha and B7.1 together induced a more potent antitumor immune response than either molecule alone, 25% higher than IL-2-TNF alpha and 20% higher than B7.1, respectively. CONCLUSION: The IL-2-TNF alpha fusion gene and B7.1 gene act in concert to improve their antitumor effectiveness.

Animals↗

PubMed2000

Effect of anti-P-selectin monoclonal antibody on renal ischemia/reperfusion injury in rats.

OBJECTIVE: To explore the effect of anti-P-selectin monoclonal antibody (mAb) on renal ischemia/reperfusion (I/R) injury in rats. METHODS: Renal function, renal histopathological changes, plasma P-selectin levels and renal P-selectin protein and mRNA expression were studied in a renal I/R injury rat models. Biochemical measurement, ELISA, Immunohistochemistry and Nested RT-PCR were used. RESULTS: Renal function insufficiency and renal histopathological damage were much less in the anti-P-selectin mAb-treated group than the saline-treated group. Plasma P-selectin levels were lower and renal P-selectin protein and mRNA expression were down-regulated in the former group. CONCLUSION: Anti-P-selectin mAb might be an efficient approach for the treatment of renal I/R injury.

Animals↗

PubMed2000

Two cases of combined liver-kidney transplantation.

OBJECTIVES: To report the clinical experiences of simultaneous hepatorenal transplantation. METHODS: We performed simultaneous hepatorenal transplantation in one patient with liver cirrhosis of hepatitis B and uremia of chronic nephritis on February 1, 1999 and one patient with liver cirrhosis of hepatitis B complicated by hepatorenal syndrome on March 12, 1999. The donors were heart arrest cases. Rapid multiple organ harvesting techniques and UW solution infusion in situ were used. Liver and kidney transplantation were orthotopic and ordinary methods, respectively. Immunosuppressive drugs consisted of cyclosporine, Cellcept, ALG and cortstco steroids. Lamividine was used on day 50 and day 40 postoperation, respectively. RESULTS: Both transplanted organs rapidly achieved normal function postoperation and the patients recovered well but suffered mild kidney rejection day 110 postoperation in No 1 patient. In No 2 patient, acute renal function failure, mental symptoms, muscle spasm, cerebral artery thrombosis, inhalation pneumonia and chronic liver graft rejection ensured sequentially but were controlled. The patients have survived for more than nine and eight months, respectively, with normal life quality. CONCLUSIONS: Combined hepatorenal transplant is a radical treatment method for liver and kidney function failure and requires more comprehensive techniques than isolated single organ transplantation. Preventing the recurrence of hepatitis B by oral lamividine may be a key to long-term survival.

Adult↗

PubMed2000

[Change of plasma cellular fibronectin values in hypertension disorders of pregnancy].

OBJECTIVE: To investigate change of plasma values of cellular fibronectin (cFN) in pregnant women with hypertension diseases. METHODS: One hundred and twelve pregnant women were assigned into five groups according to definition of hypertension diseases in pregnancy published by the National Working Group on Hypertension. The values of plasma cFN were measured with enzyme-link immunosorbent assay (ELISA). Statistical tests were performed with Variance Analysis (Scheff's post-hoc). RESULTS: Plasma cFN values in women of preeclamptic group (12.25 +/- 4.00) mg/L and superimposed preeclamptic group (11.33 +/- 3.74) mg/L were both significantly higher than those of normal group (5.06 +/- 1.33) mg/L (P < 0.01). However, cFN values were not statistically different between women of chronic hypertension or transient hypertension and of normal women (P > 0.05). CONCLUSION: The clinical detection of plasma cFN values appears to be useful in differentiating various hypertension diseases of pregnancy and in selection of relevant treatment regimen.

Female↗

PubMed2000

[Molecular cytogenetics of bone tumors].

OBJECTIVE: To study alterations of molecular cytogenetics of bone tumor serially. METHODS: Chromosomal analysis, immunohistochemistry, molecular hybridization, nested-PCR/SSCP, DNA sequence analysis, and gene transfection techniques were used to investigate the common bone tumors. RESULTS: Chromosomal aberrations were found in 50 cases of aggressive bone tumors, with a chromosome number aberration rate of 86.96% and a structure aberration rate of 93.94%. However, there were differences among different kinds of bone tumors. The incidence of chromosomal instability in 53 patients with bone tumors was higher than that in normal controls. Meanwhile, the fragile sites of chromosomes of the patients were closely correlated with the high nonrandom chromosome breakpoints of tumor cells and related oncogene loci. The data on p53 and Rb from 305 cases and 89 cases, respectively, indicated that abnormalities of p53 and Rb were common events in bone tumors. The accumulation of p53 protein and loss of Rb protein were more common in aggressive bone tumors. Structures and their products of related proto-oncogenes (ras, myc, fos, bcl-2, met) were studied in 124 cases. Bone tumors presented multi-oncogenes abnormalities with differences in different pathological kinds. Exogenous wild-type p53 gene transfected into osteosarcoma cell line induced growth inhibition and apoptosis of tumor cells. CONCLUSIONS: Abnormalities of chromosomes, proto-oncogenes, and tumor suppressor genes frequently exist in bone tumor cells and are correlated with oncogenesis.

Bone Neoplasms↗

PubMed2000

[Iodine-125 labeled monoclonal antibody 3H11: in radioimmunoguided surgery for primary gastric cancer].

OBJECTIVE: To evaluate the clinical usefulness of iodine-125 labeled monoclonal antibody (MAb) 3H11 in radioimmunoguided surgery (RIGS) for patients with gastric cancer. METHODS: Thirty-five patients with primary gastric cancer were enrolled. Via endoscopy, iodine-125 labeled MAb 3H11 was injected into submucosa around the tumor. All patients underwent surgery 4 to 11 days after administration. Intraoperative radioimmunodetection was performed using a hand-held gamma-detecting probe. The counts of target sites were obtained, and tumor-to-normal tissue (T/NT) ratios were calculated. The T/NT ratio of 3.5:1 was taken as the lowest threshold value of positive gastric wall infiltration, and 3.0:1 for lymph node metastasis. Serial sections of those RIGS-positive lymph nodes, which were originally diagnosed as negative by routine histology, were made. Immunohistochemical staining was performed to detect the existence of lymphatic micrometastasis. RESULTS: Of thirty-five patients, 33 underwent RIGS successfully. The accuracy rate in detecting tumor infiltration of the incision margins was 97.0%, and the specificity 98.5%. In the group of patients with an interval of 6 to 8 days between injection and operation (n = 25), the RIGS results were satisfying. For the detection of lymphatic metastasis, the sensitivity of RIGS was 83.6%, the specificity 95.0%, and the accuracy 91.3%. The existence of lymphatic micrometastasis were verified immunohistochemically in 52.6% (10/19) of those RIGS positive but histologically negative lymph nodes. CONCLUSION: This study validates the use of iodine-125 labeled monoclonal antibody 3H11 for the intraoperative detection of carcinomatous lesions in gastric cancer.

Adult↗

PubMed2000

[The effect of artificial tears on corneal surface regularity in dry eye].

OBJECTIVE: To evaluate the regularity of corneal surface and the effect of artificial tears on the corneal surface regularity in dry eye. METHODS: The surface regularity index (SRI), surface asymmetry index (SAI), the indices of TMS-1 corneal topography system, and potential visual acuity (PVA) were used to investigate the corneal regularity and corneal vision in 33 normal subjects (64 eyes) and 22 dry eye patients (42 eyes) before and after instillation of artificial tears. RESULTS: The SRI and SAI were significantly elevated and the PVA was remarkably decreased in patients with dry eye compared to that of normal subjects (P < 0.001). The average amount of astigmatism was also significantly increased in dry eye compared to that in normal eyes (P = 0.02). In the patients with dry eye, the SRI and SAI were positively correlated with corneal fluorescein staining scores. The SRI, SAI and astigmatism were significantly reduced, the PVA was improved and the irregular topographic pattern was markedly decreased in the dry eyes after the usage of artificial tears. CONCLUSION: The dry eye has an irregular corneal surface and the indices of TMS-1, SRI and SAI can be used to objectively diagnose this disorder, evaluate the severity of the dry eye and the effect of artificial tears on it. Artificial tears can smooth the corneal surface and improve the visual acuity in patients with dry eye.

Aged↗

PubMed2000

[The abnormal expression of epidermal growth factor receptor family in pterygium].

OBJECTIVE: To evaluate the expression of type 1 growth factor receptor family [epidermal growth factor receptor (EGFR), ErbB2 and ErbB3] by the epithelium in pterygium so as to understand the pathogenesis of this disorder. METHODS: The immunofluorescent staining and Western blotting were performed in 15 patients with primary pterygium, compared to normal conjunctival epithelium, to determine the expression of EGFR, ErbB2 and ErbB3 proteins. RESULTS: The EGFR was present at the basal cells while the ErbB2 and ErbB3 were expressed by the superficial cells in normal conjunctival epithelium in immunofluorescent staining. Of 15 pterygia, 11 pterygia expressed the stains of EGFR, ErbB2 and ErbB3 in the full thickness of epithelium and with stronger staining compared to the control group, 4 of them showed the same staining pattern as that in the normal conjunctiva. Compared to normal conjunctiva, the stronger density of protein bands of EGFR, ErbB2 and ErbB3 was also demonstrated by western blotting in 11 pterygia with strong staining of these antibodies. CONCLUSIONS: The expression of EGFR, ErbB2 and ErbB3 is increased in pterygium, showing that the pterygium is a disorder with proliferation. The abnormal expression of EGFR, ErbB2 and ErbB3 by epithelium and their communicating with cytokines at stroma in pterygium may be one of the key pathogenetic factors in this disorder.

Adult↗

PubMed2000

[The measurement of normal values of exophthalmos, interpupillary distance and interorbital distance of children and adolescence in Xiamen and the rule of their development].

OBJECTIVE: To investigate the developing rhythm of children and adolescent exophthalmos, interorbital distance (IOD) and interpupillary distance (IPD) and their mutual relationships. The study will provide biometry data for formulating juvenile criteria of correcting spectacles. METHODS: Random sampling was performed among children and adolescence aged 5 - 17 years in Xiamen. Adopting epidemic survey, we measured the biometry values of IOD, IPD and exophthalmos with a sliding gauge and exophthalmometer. RESULTS: The average value of exophthalmos was (14.48 +/- 1.71) mm. For the 5 - 8 years old children, the value of exophthalmos trended to increase with the increase of age, meanwhile the value of exophthalmos of adolescence aged 9 - 17 years old tended to be stabilized. The average value of IOD was (95.55 +/- 5.32) mm and the average value of IPD was (56.99 +/- 3.93) mm. Both the values of the IOD and IPD of the male were higher than that of the female. The results of the IOD and IDP distance increased with the increase of age and it trended to be periodic. There was positive correlation between the development of IOD and that of IPD, and it could be described by a linear equation. CONCLUSIONS: There is only one rush-increase stage of ocular development which is before the 8 years old in children. The rule of its development is in accordance with the growing and developing mode of neurological system.

Adolescent↗

PubMed2000

[Effect of sodium fluoride on bone turnover and bone loss of vertebrae and tibia in ovariectomized rats].

OBJECTIVE: To investigate the effect of sodium fluoride on bone turnover and bone loss of vertebra and tibia of ovariectomized rats. METHODS: 34 female Wistar rats, 16 weeks old, were divided into 3 groups: sham-ovariectomy (CON), bilateral ovariectomy (OVX) and both OVX and NaF-treatment groups (OVX + NaF, 1.0 mg/kg BW). All of the rats were sacrificed 12 weeks after the treatment. Serum was collected for the analysis of estradiol, calcium, phosphorum and alkaline phosphotase. Temur was used for the analysis of calcium content. Tibiae and the first lumbar vertebral bodies were decalcified for histomorphometry. RESULTS: After treatment with NaF, bone resorption was not inhibited, but bone formation was significantly increased. The trabecular bone volume of vertebrae (18.73% +/- 3.04%) and tibiae (14.30% +/- 5.87%) was significantly increased in comparing with of OVX rats (15.07% +/- 2.45% and 8.81% +/- 2.60%, P < 0.05), but it was markedly lower than that of CON rats (22.44% +/- 1.82% and 24.87% +/- 4.02%, P < 0.05 and P < 0.01). CONCLUSIONS: NaF could not decrease bone turnover and it, has only a partial protective effect against bone loss of either vertebra or tibia.

Animals↗

PubMed2000

[The expression of DNA mismatch repair genes and detection of DNA ploidy in young patients with colorectal carcinoma].

OBJECTIVE: To investigate the clinicopathologic characters and carcinogentic pathways of young (age < 36) colorectal carcinomas (CRCs) in Guangzhou, China. METHODS: Immunohistochemistry and flow cytometry methods were used to detect the expression of hMSH(2) and hMLH(1), status of DNA ploidy in 63 cases of young CRCs from Guangzhou, China, and analyze their correlations with patient's clinicopathological characters. RESULTS: Of the 63 young CRCs studied, forty-four (69.8%) tumors were non-mucinous carcinomas, thirty-nine (61.9%) patients were in Dukes' C or D stage. Of the 59 CRCs which were successfully detected by immunohistochemistry and flow cytometry, ten (16.9%) CRCs lost either hMSH(2) or hMLH(1) and showed DNA diploid or near-diploid, while twenty-six (44.1%) had aneuploid DNA content and all with the normal expression of hMSH(2) and hMLH(1). In addition, there existed a significant percentage (23/59, 39%) of young CRCs showing no loss of either of these two mismatch repair proteins and having a diploid or near diploid DNA content. CONCLUSION: The overall percentage of young CRCs in Guangzhou is significantly higher than those in Caucasian predominant countries and about seventy percent of young CRCs in Guangzhou are conventional carcinomas. 39% of young CRCs in Guangzhou showed no evidence of either chromosomal instability or microsatellite instability carcinogentic pathway, indicating that there must be at least a third pathway which triggers the CRCs in these special subgroups of young patients in Guangzhou, China.

Adaptor Proteins, Signal Transducing↗

PubMed2000

[A report of 115 cases of amputation after electric injury].

OBJECTIVE: To analyze the main features of amputation subsequent to electric injury. METHODS: One hundred and fifteen cases of amputation were analyzed with the purpose to define the indication, the optimal level, operational methods and the prognosis. RESULTS: The incidences of amputation in this group were 45.4% for upper and 14.9% for lower extremities, respectively. The indications were total necrosis of the extremities, secondary necrosis of the extremities due to the thrombosis, bleeding and rupture of the major supplying arteries and failure to restore severely injured tissue. The commonest amputation levels were the mid third and the upper third of the forearms. The primary healing rate was 63.5%. CONCLUSION: It was very important to identify the optimal indications, the proper levels and operational methods for the amputation after electric injury, so as to make stumps more suitable for the installation of artificial limbs to restore better function.

Amputation, Surgical↗

PubMed2000

[Analysis of riboflavin status in severely burned patients].

OBJECTIVE: To investigate riboflavin status in severely burned patients. METHODS: Thirty-two severely burned patients were enrolled in the study with TBSA of 30.2 plus minus 10.9% and average burn index of 19.7. The everyday intake amounts of riboflavin, protein and calorie via different routes by each patient were recorded. Fluorescence method was employed to detect 4 hour urine load test in the 32 patients after oral taking of riboflavin on 3 similar 7 and 8 similar 14 postburn day (PBD). RESULTS: The averaged everyday intake amounts of protein and calorie by each patient in this study on 3 similar 7 and 8 similar 14 PBDs reached the requirement of Chinese burn patients' nutritional supplying formula. And protein administration occupied 17% similar 18% of total calorie. The averaged everyday intake of riboflavin by each patient was 3 similar 5 mg. But 4 hour urine load test exhibited that average urine discharging amount of riboflavin was all less than 400 microgram. CONCLUSION: There existed obvious systemic deficiency of riboflavin on 3 similar 14 PBD in severely burned patients.

Adult↗

PubMed2000

[The expression of Fas antigen and plasma levels of sFas and sFasL in patients with aplastic anemia].

OBJECTIVE: To investigate the role of Fas/FasL system in the pathogenesis of aplastic anemia (AA) and its correlation with clinical status. METHODS: Plasma levels of sFas and sFasL and the expression of Fas antigen on mononuclear cell (MNC) membrane in 32 AA patients and 24 normal controls were assayed by ELISA and FACS, respectively. RESULTS: The percentage of CD(34)(+)Fas(+) cells was significantly higher (P < 0.05) in AA patients than that in normal controls, and the percentage of CD(34)(+)Fas(+) cells in severe AA patients was much higher than that in chronic AA patients (P < 0.05). The percentage of CD(34)(+)Fas(+) cells was negatively correlated with the course of disease. The levels of sFas were significantly lower (P < 0.05) in AA patients than that in normal controls, and the sFas levels in severe AA were much lower than those in chronic AA (P < 0.05). The percentage of CD(34)(+)Fas(+) cells was negatively correlated with sFas level. CONCLUSION: Fas/FasL system aberration is involved in the pathogenesis of AA.

Adolescent↗

PubMed2000

[Regulation of telomerase activity in HL-60 and NB4 cells by arsenic trioxide].

OBJECTIVE: To investigate the regulation of telomerase activity in HL-60 and NB4 cells exposed to arsenic trioxide (As(2)O(3)). METHODS: Cell morphology, intracellular DNA distribution, bcl-2 expression and telomerase activity were evaluated in HL-60 and NB4 cells exposed to As(2)O(3) or ATRA. RESULTS: The differentiation induction of HL-60 and NB4 cells by low concentration of As(2)O(3) was weaker than that by ATRA, but downregulation effect of As(2)O(3) on telomerase activity was more strong and quick. Higher concentration of As(2)O(3) induced apoptosis in HL-60 or NB4 cells accompanied by more rapid down regulation of telomerase activity and bcl-2 expression. Neither As(2)O(3) nor ATRA showed direct inhibition effect on telomerase activity. CONCLUSION: The downregulation of telomerase activity by low concentration of As(2)O(3) in HL-60 and NB4 cells is the result of overlap of differentiation and apoptosis. There are similar mechanisms in the regulation of telomerase activity and apoptosis in different leukemia cells. Bcl-2 may play an important role in these mechanisms.

Apoptosis↗