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Biomedical subjects

S Liu

Publications and source records attributed to S Liu.

At least 487 records · Page 27Linked to original sources
PubMed1999

[Transplantation of neural retina after photic injury of retina in mice].

OBJECTIVE: To examine the possibility of retinal photoreceptors rescued after photic injury by allogeneic neural retinal transplantation. METHODS: The retinal photic injury model was established by a light-damage trunk designed by ourselves. After photo-illumination, 60 mice were divided into two groups: Group I (n = 20) was the photic injury group and group II (n = 40), the retinal transplantation group; then group II was subdivided into II(A) (n = 20) and II(B) (n = 20) subgroups. External approach for neural retinal transplantation was performed at 24hr (group II(A)) and day 7 (group II(B)) after photic injury respectively. The recipients were sacrificed at day 6, day 12, day 18 and day 30 post-operatively to examine whether the graft could rescue the injured retinal photoreceptors. RESULTS: In group I, the inner and outer segment showed edema, disorganization and vesiculation, the outer nuclear layer became very thin and disorganized, and the cell nuclear chromatin showed pyknosis and margination. In group II, the graft survival rate in group II(A) was 50% (10/20) and in group II(B) was 80% (16/20), the difference being significant (chi(2) = 3.956, P < 0.05). Among the graft survival samples, we compared the rescue rate of photoreceptors between group II(A) 40% (4/10) and group II(B) 50% (8/16), the difference being not significant (P = 0.702). CONCLUSION: The retinal photic injury may result in photoreceptor degeneration that can be rescued by retinal transplantation, and the successful rate of the transplantation performed at day 7 is higher than that at 24-hr after injury.

Animals↗
PubMed1999

[Relationship between obese gene expressive product and simple obesity in children].

OBJECTIVE: To investigate the relationship between obese gene expressive product-obese protein (OP) and the pathogenesis and prognosis of simple obesity in 30 children with normal body weight (control group). METHODS: Before immunoassay, OP was extracted from the whole blood samples with Sep-pak C(18) Cartridge. RESULTS: The plasma contents of OP in the obese group were (118.53 +/- 25.02) ng/L and (197.14 +/- 26.83) ng/L (P < 0.001), respectively. In the obese group, plasma OP was not detected in three cases and was (19.90 +/- 3.94) ng/L in other three cases. These obese children with severe OP deficit not only had more increased body mass index, and levels of total cholesterol, triglyceride and low-density lipoprotein-cholesterol, but also had lower therapeutic effect (16.67%) than those with mild OP depletion (79.16%). CONCLUSION: The children with simple obesity have OP deficit. Simple obesity may be related with the reduced plasma content of OP. The obese children with severe OP deficit have poorer curative effect and unfavorable prognosis.

Child↗
PubMed1999

[Association of body size at birth with impaired glucose tolerance during their adulthood for men and women aged 41 to 47 years in Beijing of China].

OBJECTIVE: To explore if there was relationship between small body size at birth and type 2 diabetes and impaired glucose tolerance (IGT) during adulthood in China. METHODS: Six hundred and twenty-eight singletons born in the Peking Union Medical College Hospital in Beijing during July 1948 to the end of 1954 were followed-up and their medical records at birth were abstracted. Anthropometry and standard oral glucose tolerance test were carried out for all of them. Plasma insulin level was measured with radioimmunoassay for them. RESULTS: Prevalence of type 2 diabetes and IGT decreased with the increase in their birth weight, Ponderal index (PI) and head circumference at birth (for trend test, chi(2) = 6.7, P = 0.01; chi(2) = 4.8, P = 0.03; and chi(2) = 5.8, P = 0.02; respectively), with the highest of 43.8% in those with thin body size (PI < 24 kg/m(3)) at birth and obesity (BMI < 75 percentile) during adulthood, and the lowest of 8.3% in those with more fat at birth (PI >or= 28 kg/m(3)) and keeping relatively thin (BMI < 25th percentile) during adulthood. BMI of mothers in their early and late pregnancy correlated reversely with blood glucose levels two hours after sugar load for their children in adulthood. In addition, body weight, PI and head circumference at birth correlated reversely with their plasma insulin levels fasting and two hours after sugar load and levels of 32 -- 33 split pro-insulin during their adulthood. After adjustment for current BMI, lifestyle and economic status, body size at birth mentioned above still associated with their glucose tolerance and level of plasma insulin during adulthood. CONCLUSION: There was relationship between small body size at birth and prevalence of type 2 diabetes and IGT during adulthood. Prevalence of type 2 diabetes and IGT depended on the synergic effect of thin body size at birth and obesity during adulthood.

Adult↗
PubMed1999

[Effects of cigarette smoke solution and chrysotile on proliferation activity of human embryo lung cells].

OBJECTIVE: To study the separate and combined effects of cigarette smoke solution and chrysotile on cell proliferation activity. METHODS: Human embryo lung (HEL)fibroblasts were cultivated with cigarette smoke solution and chrysotile separately or in combination at varied concentrations for certain times, and cell proliferation was observed with [(3)H] TdR incorporation. RESULTS: Cigarette smoke solution and chrysotile could enhance cell proliferation at lower doses, both separately or in combination, but inhibit it at higher doses. Lower dose of cigarette smoke solution and chrysotile in combination could enhance cell proliferation synergistically, but higher doses could only do additively. CONCLUSION: Cigarette smoke solution and chrysotile could affect HEL cell proliferation separately or in combination, with an enhancing or inhibiting effect, which depended on their doses.

Asbestos, Serpentine↗
PubMed1999

[Plasmid DNA breakage caused by reaction of intracellular redox compound with potassium dichromate].

OBJECTIVE: To study plasmid DNA breakage induced by hexavalent chromium (Cr(VI +)) compound in vitro. METHODS: DNA breakage was observed using plasmid relaxation method. RESULTS: pUC 118 plasmid DNA single strand breakage can not be caused by either ascorbic acid (1 mmol/L), or glutathione (5 mmol/L), or hydrogen peroxide (H(2)O(2), 17 mmol/L) or potassium dichromate (K(2)Cr(2)O(7), 0.5 mmol/L) alone. But, if DNA was incubated warmly with K(2)Cr(2)O(7) and intracellular redox compound, pUC118 plasmid DNA single strand breakage could be induced by K(2)Cr(2)O(7), ascorbic acid, or glutathione, or products of peroxidation reaction. K(2)Cr(2)O(7) (0.5 mmol/L) and H(2)O(2) (17 mmol/L) also could cause some double-strand breakage in plasmid. CONCLUSION: It suggests that ascorbic acid, glutathione and H(2)O(2) can play an important role in carcinogenicity of K(2)Cr(2)O(7).

Antioxidants↗
PubMed1999

[Research on the oncogenesis of cervical epithelial cells co-induced by human papillomavirus and human cytomegalovirus].

OBJECTIVE: The carcinogenesis of the human cervical carcinoma is known closely associated with human papillomavirus (HPV). The purpose of this article is to identify whether another sexually transmitted factor, human cytomegalovirus (HCMV) plays as a co-factor role in the carcinogenesis. METHODS: Human cervical epithelial cells immortalized by HPV16 were transfected with IE gene of HCMV. The condition and efficiency of IE gene were examined. RESULTS: It was showed that the cervical epithelial cells could be completely transformed into malignant by HPV 16 and IE gene of HCMV and tumor was formed by injecting the transformed cells in nude mice. CONCLUSION: The co-operation effect of HPV and HCMV auailed the oncogenesis of human cervical carcinoma and moreover, the cellular and molecular biological mechanism was discussed.

Animals↗
PubMed1999

[Clinicopathological study of 52 cases of ameloblastoma of jaw].

OBJECTIVE: To observe the relationship between the histologic types, tumor invasion, operation mode and recurrence of ameloblastoma. METHODS: Using WHO classification (1992) for histological typing of odontogenic tumors, 52 cases of ameloblastoma were studied clinicopathologically. RESULTS: The 8 pathological types are: follicle formation type, plexiform type, acanthoma type, basal cell type, granular cell type, desmoplastic ameloblastoma, kerato ameloblastoma and ameloblastoma accompanied by bone formation. Recurrence in the 8 above types following surgery were 5/11, 0/5, 7/15, 5/8, 0/3, 0/3, 2/3 and 1/4 respectively. Five cases recurred in 21 patients with tumor cells infiltrating into the connective tissue surrounding the tumors. 12 cases recurred in 16 patients with tumor cells infiltrating thru the capsule into surrounding soft tissue. The recurrence rate in patients who had their tumor enucleated or curetted was 56.5% (13/23). The recurrence rate in the tumors resected together with involved bone segment was 24.1% (7/29). Multiple recurrences occurred in 3 cases whose tumors were not well differentiated and had atypical cells. CONCLUSIONS: Recurrence was more often seen in the follicular, acanthoma, basaloid, and keratoid types of ameloblastoma. When these tumors invade adjacent soft tissues, the recurrence rate is also higher. Recurrence is linked to conservative surgery and to tumors with low differentiation.

Adolescent↗
PubMed1999

[Significance of telomerase activity detection by fine-needle aspiration in patients with breast cancer].

OBJECTIVE: To study the telomerase activity in samples of breast fine-needle-aspiration specimens and to investigate its potential clinical implications. METHODS: Ninety nine fine-needle aspiration specimens from 83 patients with breast cancers, 12 with benign lesions and 4 with breast inflammation, were studied for the presence of telomerase activity by a PCR-based telomere repeat amplification protocol (PCR-TRAP). RESULTS: Among 83 fine-needle aspiration specimens from patients with breast cancer, telomerase activity was detected in 61 of 69 cytologic-positive specimens, 5 of 7 cytologic-suspicious specimens and 4 of 7 cytologic-negative specimens. Sensitivity of telomerase activity detection was 84.3% (70/83); the coincidence rate between telomerase detection and cytologic confirmation was 77.1% (64/83). Of 12 specimens from patients with benign breast lesions, 4 were positive for telomerase activity, but 4 specimens from patients with breast inflammation were all negative. The Combined use of cytological and telomerase detection can improve the detection rates from 83.1% (69/83) to 93.9% (78/83). CONCLUSION: Detection of telomerase in breast tissue samples by fine-needle aspiration is a sensitive and specific method, which implies that it would be helpful in preoperative cytological diagnosis of breast cancer.

Biopsy, Needle↗
PubMed1999

[A clinicopathological study of pancreatoblastoma].

OBJECTIVE: To investigate the clinicopathological, immunohistochemical features and the histogenesis of pancreatoblastoma (PB) in 14 pediatric cases, including 9 male and 5 female patients, their age ranged from 1.5 to 8 years with a mean of 4.4 years. METHODS: Routine pathological, histochemical, and immunohistochemical methods were utilized to analyse the PB specimens. RESULTS: Tumors of 6 patients had metastasized to the liver, spleen and lymph nodes, 8 patients were alive 10 months to 105 months after diagnosis. Histologically, the tumors were composed of dense epithelial elements separated by fibro-stromal tissue, resulting in a nesting or organoid pattern. Immunohistochemically and histochemically, the tumors exhibited acinar, endocrine and ductal differentiation. The positive rates for were: CK 100%, EMA 86%, NSE 79%, CEA 71%, SYN 64%, CgA 43%, alpha1-AT 57%, PAS 100% and mucicarmine 57%. CONCLUSIONS: PB is the most common malignant pancreatic neoplasm of childhood. PB arises from primitive pluripotential cells capable of differentiating into 3 pancreatic cell types: acinar, endocrine and ductal. The prognosis is better than pancreatic carcinoma in adults.

Carcinoembryonic Antigen↗
PubMed1999

[Determination of vitamin E in juices by high performance liquid chromatography (HPLC)].

A modified method for the determination of tocopherol(vitamin E) in juices by high performance liquid chromatography(HPLC) has been proposed in this paper. The juice samples were deproteinized with ethanol and extracted with hexane. Organic layer was evaporated to dryness with nitrogen after it was separated. Then the residue was redissolved with methanol and injected into a reversed-phase HPLC equipped with a C18 column. The tocopherols were eluted with methanol mobile phase at a flow rate of 1.0 ml.min-1 and detected by fluorescence(lambda exc = 295 nm, lambda em = 330 nm). A good linearity was shown between the concentration of tocopherol and the peak height at the concentration range of 0.2-2.2 micrograms.ml-1(r = 0.9995, n = 5). The recovery rate was more than 96.8%, and impurities in the samples were separated completely. This method is sensitive, simple and stable.

Beverages↗
PubMed1999

[Effect of nitric oxide on HSV-1 infection of HeLa cells and Vero-E6 cells].

The effects of nitric oxide(NO) on HSV-1 infection of HeLa cell line and Vero-E6 cell line were investigated in this study. The titers of HSV-1 in supernatants from infected culture of Vero-E6 cells were decreased by a NO donor, sodium nitroprusside(SNP), in a dose-dependent manner, while the control compound potassium ferricyanide (KFC) had no effect. However, SNP had no effect on that of HeLa cells. The results reaffirm the antiviral effect of NO and suggest that the susceptibility of different cell lines to the effect of NO might be varied.

Animals↗
PubMed1999

[Specific cellular and humoral immune responses induced by intramuscular injection of DNA vaccine containing HBV HBsAg gene in mice].

To know the influences on the function of cellular and humoral immunity in mice by DNA vaccine containing HBV HBsAg gene, the DNA vaccine, pcDNA3-HBsAg, in which the HBsAg gene sequences of HBV were inserted into downstream of CMV promoter in pcDNA3, were injected intramuscularly into Balb/C mice. The results were that the serum anti-HBsIgG was detected in all of the pcDNA3-HBsAg immunized mice, but none in control mice; serum levels of Th1 cytokines, interleukine 2, and interferon gamma, were significantly higher in pcDNA3-HBsAg immunized mice than these in controls. It is indicated that the good responses of cellular and humoral immunity can be induced by injection of pcDNA3-HBsAg in Balb/C mice.

Animals↗
PubMed1999

[Use of transcranial Doppler in monitoring cerebral blood flow velocity during peri-operation].

Transcranial Doppler was used to monitor 45 patients' middle cerebral artery blood flow velocity during anesthesia and cardiopulmonary bypass. The result was that the change in middle cerebral artery blood flow velocity was in correspondence with cerebral blood flow. This paper suggests that transcranial Doppler is a simple and practical instrument for monitoring cerebral blood flow.

Adolescent↗
PubMed1999

[Changes in trace elements in epithelial cells of oral submucous fibrosis].

OBJECTIVES: To assay the concentrations of the trace elements in intranuclei and extranuclei between oral submucous fibrosis (OSF) and normal buccal membrane, to observe the relationship between the trace elements and OSF, and finally to understand the mechanism of OSF. METHODS: The concentrations of the trace elements of internuclei and extranuclei in OSF epithelial cells were assayed in computer automatic process by electron probe micro-analysis. RESULTS: The concentrations of Cu, Zn, S, and As in OSF were significantly lower than those in the normal buccal membrane (P < 0.01). The concentrations of Se and Mo were significantly higher than those in the normal buccal membrane(P < 0.01). CONCLUSION: The epithelial cells of OSF are seriously damaged by the low level of Cu and Zn and high level of Se in intracell. These changes are the element bases that OSF has canceration trend.

Copper↗
PubMed1999

[Research on cause of distinction in antiendotoxic activation of radix isatidis from different cultivated populations].

OBJECTIVE: To research into the cause of distinction in antiendotoxic activation of Radix Isatidis from different cultivated populations. METHOD: 19 samples of Radix Isatidis were gathered. 12 portions of seeds were cultivated in the same field in Shanghai, and the selected and artificially bred autotetraploid seeds were planted in 5 different locations. All the samples were compared through antiendotoxic experiment. RESULTS: There are some marked distinction among the 19 samples from different populations. The distinction of the 12 samples cultivated in the same field didn't disappear. The activation of autotetraploid from 5 different locations didn't vary on the whole. CONCLUSION: Germplasm is the main factor to cause activation distinctions of Radix Isatidis, while environment is less important.

Drugs, Chinese Herbal↗
PubMed1999

[A study on producing areas of Chinese flos Dendranthematis].

OBJECTIVE: To probe into the cultural environment and changes of producing areas of different species of Chinese Flos Dendranthematis. METHOD: On-the-spot investigation and literature study. RESULTS: A clearer idea has been gained on the geographical distribution, growing environment and changes of producing areas of Gongju, Hangju, Chuju, Boju, Huaiju and Jiju. CONCLUSION: Different environments fit for the growth of different species of Flos Dendranthematis. The present study provides some valuable information on the cultivation and development of Chinese Flos Dendranthematis.

Asteraceae↗
PubMed1999

[Species evolution of Chinese flos Dendranthematis].

OBJECTIVE: To probe into the history and current situation and main producing areas of different species of Chinese Flos Dendranthematis. METHOD: On-the-spot investigation, cultivation observation and literature study. RESULTS: Morphological characteristics of different species of Flos Dendranthematis were clarified, and the historical changes of these species were studied. CONCLUSION: Congju is related to Hangju. Boju is related to Huaiju. Jiju and Qiju, and Chuju is a distinctive species. These findings are important for the cultivation and processing of Chinese Flos Dendranthematis.

Asteraceae↗