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Q Lan

Publications and source records attributed to Q Lan.

35 records · Page 2Linked to original sources
PubMed1999

[Risk state analysis on lung cancer of male in Xuanwei, China].

The analysis of lung cancer risk factors among male population was based on the data of a retrospective cohort study conducted during 1976-1996 in Xuanwei, China. The results verified that the indoor air pollution from burning smoky coal was the main cause of high lung cancer mortality, and found that cigarette smoking was also significantly related with the lung cancer mortality. Using risk state analysis theory, fuel types(including household stove improvement), smoking and the history of chronic bronchitis were selected as the covariance for the analysis. A risk state analysis model for male lung cancer in Xuanwei was established. The model can be used to quantitatively estimate the risk of lung cancer and to determine high risk population and individuals. The model is helpful for the prevention of lung cancer in Xuanwei.

Adult↗
PubMed1998

[5 cases report of Kaposi's sarcoma].

OBJECTIVE: To aid clinical diagnosis and management of Kaposi's sarcoma. METHODS: 3 male and 2 female of classical Kaposi's sarcoma were analysed by clinical and pathological examinations. RESULTS: All the patients presented hemorrhagic or flue plagues nodules that could be fused together or ulceration. The lesions could reappear and get relived by themselves, The retroperitoneal lymphnodes was involved in one case, together with hypoxemia, oral ulceration, conjunctivitis and keratitis. The tumor behaved intensive spindle-cell sarcoma with obvious karyokinesis. CONCLUSION: The affected organ in classical kaposi's sarcoma were mainly skin, rarely internal organs. The diagnosis were verified on pathology and the treatment could rely on radiotherapy, chemotherapy and local resection.

Adult↗
PubMed1997

DNA transfection in the ecdysteroid-responsive GV1 cell line from the tobacco hornworm, Manduca sexta.

The embryonic cell line, GV1, from Manduca sexta was transiently transfected with DNA constructs of the Drosophila hsp70 promoter fused to either a beta-galactosidase (pXH70ZT) or a chloramphenicol acetyl transferase (HSP-CAT-1) reporter gene using lipofectin. Optimal cell density, DNA:lipofectin ratio, and time of incubation were varied to determine the optimal conditions: 2 x 10(5) cells/ml, 1:3, and 5 h. Under these conditions, the transfection efficiency was about 40%. Heat inducibility of two hsp70 constructs was compared. The HSP-CAT-1, containing 1127 bp of upstream sequence, was more sensitive to heat shock than that of pXH70ZT, containing only 194 bp of upstream sequence. Thus, the 1127 bp hsp70 promoter appears to be a better inducible promoter in these cells. A 2 kb fragment of the proximal promoter region of the MHR3 gene containing a putative ecdysone response element was shown to be responsive to 20-hydroxyecdysone after its transfection into these cells.

Animals↗
PubMed1997

Regulation of the ecdysone receptor, USP, E75 and MHR3 mRNAs by 20-hydroxyecdysone in the GV1 cell line of the tobacco hornworm, Manduca sexta.

The responsiveness of several nuclear transcription factor genes to 20-hydroxyecdysone (20E) was characterized in an embryonic cell line, GV1, from Manduca sexta. The mRNA for the Manduca ecdysone receptor (MsEcR) was present in the GV1 cells and transiently increased 2.3-fold by 5 h after the addition of 2 micrograms/ml (4 x 10(-6) M) 20-hydroxyecdysone (20E). In contrast, Manduca ultraspiracle (MsUSP) mRNA level in the GV1 cells decreased slowly to half of its initial level by 12 h when exposed to the same concentration of 20E. The mRNAs for two putative transcription factors, MsE75 and MHR3, were induced in the GV1 cells by 20E, with that for E75 appearing within 1 h whereas that for MHR3 within 2 h. The ED50S for induction of MsE75 and MHR3 gene expression in GV1 cells were 1.2 x 10(-6) and 2.5 x 10(-6) M 20E, respectively.

Animals↗
PubMed1996

Preclinical evaluation of SPECT imaging with 131I-labeled monoclonal antibody SZ39 in nude mice bearing human glioma xenografts.

The imaging characteristics of monoclonal antibody SZ39 against glioma were evaluated in glioma-bearing nude mice. Monoclonal antibody SZ39 is a murine IgG2a that reacts with a glycoprotein epitope (molecular weight 180,000), a human glioma-associated membrane antigen. Monoclonal antibody SZ39 was labeled with 131I using a modified chloramine T method. Each glioma-bearing nude mouse was given 50 microCi/40 micrograms of the experimental agent, 131I-labeled monoclonal antibody, or 50 microCi/46 micrograms of a control agent, 131I-labeled monoclonal antibody C50, an antibody against colon cancer. Single-photon emission computed tomography (SPECT) was performed every 24 hours in the first week after administration. Glioma-bearing nude mice were killed in groups of 3 at 24 hours and daily up to 72 hours. The ratio of radioactivity uptake in glioma to normal organs was calculated. After administration of the labeled SZ39, glioma was visualized with SPECT on days 1 to 7, particularly at 72 hours. There was no accumulation of radioactivity in glioma with the labeled C50 antibody. All glioma-organ ratios increased with time. At 72 hours, the ratio of glioma to brain was 22.46 and of the other organs was 2.64 on average. SZ39 had a relatively low endocytosis rate and was favorable for 131I labeling. These characteristics were helpful to reduce free 131I in the blood and reduce the uptake by other organs. The results suggest that 131I-labeled SZ39 selectively accumulates in glioma, representing a potential strategy for SPECT imaging of these lesions.

Adult↗
PubMed1996

Target imaging diagnosis of human brain glioma. Clinical analysis of 40 cases.

OBJECTIVE: To establish a method for localization and qualitative diagnosis of glioma. METHODS: The monoclonal antibody SZ-39 against human glioma was labelled with 131I and injected intravenously into 40 patients with intracranial occupying lesions proved by X-CT. 72 hours after 131I-McAb-SZ39 administration, cranial bone nuclide-imaging agent 99mTc-MDP was injected intravenously, and the patients were examined by SPECT scan with dual nuclide double channel tomography and special software. On radio-immuno-image, the immunocomplex formed by specific conjugation of 131I-McAb-SZ39 with target tissue was red, while the cranial bone incorporated with 99mTc-MDP was green. The location of the immunocomplex area could be identified by the superimposition of the images. RESULTS: 21 patients with positive targeting diagnosis of glioma showed the accuracy rate checked by SPECT was 81%(17/21) and by X-CT 48% (10/21). Seven patients with negative targeting diagnosis showed the accuracy rate checked by SPECT was 86%(6/7) and by X-CT 14% (1/7). Pathologically, the sensitivity of targeting SPECT to glioma was 94.5%(17/18) and that of X-CT 55%(10/18). CONCLUSIONS: Targeting SPECT examination could be used for localization and qualitative diagnosis of glioma and make up the inadequacy of X-CT in the qualitative diagnosis of atypical incipient and recurrent glioma, meningioma, metastatic carcinoma, and inflammatory lesions of brain.

Adolescent↗
PubMed1994

Mosquito ribosomal protein rpL31 resembles rat rpL34: cDNA and deduced amino acid sequence.

An Aedes albopictus ribosomal protein rpL31 cDNA was sequenced, and found to encode a protein with homology to rat rpL34. The 544 bp mosquito cDNA contained an ATG start site, three in-frame termination codons, and an AATAAA polyadenylation signal. Mosquito rpL31 had a mass of 15,137 Da, a pI of 12.39 and contained 14.5% Arg and 14.5% Lys. PCR analyses with genomic DNA suggested the presence of a large intron near the 5'-end of the gene.

Aedes↗
PubMed1994

Stimulation of transcription factors NF kappa B and AP1 in endothelial cells subjected to shear stress.

Hemodynamic shear stress forces influence several important endothelial genes associated with arterial relaxation, pro/anti-coagulation, and growth control; however, the regulatory pathways remain unclear. Here we demonstrate stimulation of DNA binding activities of nuclear factor kappa B (NF kappa B), a member of the Rel Family of transcription factors, and nuclear factor activator protein-1 (AP-1) following exposure of endothelial cells to unidirectional shear stress in laminar flow. NF kappa B binding was stimulated within 30 minutes, reaching and maintaining maximal levels at 1 hour. DNA binding activity was inhibited by pre-incubation of nuclear extract with antibody directed against NF kappa B p65 subunit. AP-1 binding activity was biphasic, rising fourfold within 20 minutes and returning to basal levels before steadily increasing by 2 hours to a high level relative to basal values. These protein kinase C-coupled transcriptional factors may modulate endothelial genes that are shear stress-responsive and that possess appropriate binding sites in the promoter region.

Animals↗
PubMed1993

Cultured Aedes albopictus mosquito cells synthesize hormone-inducible proteins.

To provide a framework for biochemical investigation of ecdysteroid action in Aedes albopictus mosquito cells, we examined the effect of 20-hydroxyecdysone on cell growth and morphology, synthesis of inducible proteins (EIPs), and expression of a transfected gene regulated by a synthetic ecdysteroid response element. When cells were cultured in the continuous presence of 10(-6) M 20-hydroxyecdysone, the rate of growth decreased and subtle changes in cell morphology were observed. In both Aedes aegypti and A. albopictus cells, synthesis of a small number of radiolabeled proteins, which appeared as minor bands on sodium dodecyl sulfate-polyacrylamide gels, was induced by treatment with 20-hydroxyecdysone. On two-dimensional polyacrylamide gels, 11 EIPs, ranging in size from approximately 22 to 52 kDa, were identified in A. albopictus C7-10 cells. Ten inducible proteins were localized in the cytoplasmic fraction; EIP28 and EIP31 were detected in both cytoplasmic and nuclear extracts, and EIP29 was detected only in the nucleus, at a very low level. None of these proteins corresponded to small heat shock proteins, whose genes are 20-hydroxyecdysone-inducible in some Drosophila cell lines. The juvenile hormone analog, methoprene, induced expression of a 25 kDa protein in C7-10 cells. Although 20-hydroxyecdysone sustained the synthesis of this methoprene-inducible protein, synthesis did not occur in the presence of 20-hydroxyecdysone alone. In transfected A. albopictus cells, expression of a recombinant DNA construct containing two tandem synthetic ecdysteroid regulatory elements based on a D. melanogaster small heat shock protein gene was modestly induced by 20-hydroxyecdysone.

Aedes↗
PubMed1993

Risk factors for lung cancer in non-smokers in Xuanwei County of China.

Tobacco smoking and some types of occupational exposures have consistently been considered as important etiologic factors of lung cancer in industrial countries. At the First World Conference of Lung Cancer (Wyndwer, 1983), it was stressed that more attention should be paid to finding out the causes of lung cancer in non-smokers. In Xuanwei County, Yunnan Province, annual lung cancer death rate was 27.7 per 100,000 in males, among China's highest, and 25.3 per 100,000 in females, the China's highest. The female's lung cancer death rate in Xuanwei County was even much higher than that of the same period in USA white women (ECACM, 1979; Mulvihill, 1976). Marked district variation in cancer mortality exists within Xuanwei County. The county can be divided into high-, medium- and low-mortality areas. Over 90% of the population are farmers. The local residents traditionally burned three major kinds of fuels: "smoky" coal, "smokeless" coal and "wood", for heating and cooking. The three lung cancer high mortality areas, including "Chengguan", "Rongcheng" and "Laibin" communes, mainly burned the "smoky" coal from Laibin smoky-coal mine. The fuel was burned in a shallow, unventilated fire pit in the floor of the dwelling. Fuel burning in shallow unventilated pits has resulted in high indoor air pollution levels. The concentrations of airborne particles (pm 10) inside houses during smoky coal and wood combustion were very high. Indoor concentration of suspended particulates and dichloromethane extractable organics were 24.4mg/m3 and 17.6mg/m3 in burning of "smoky" coal; 22.3mg/m3, 12.3mg/m3 for burning wood; and 1.8mg/m3, 0.5mg/m3 for burning of smokeless coals.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Sequence analysis of a mosquito ribosomal protein rpL8 gene and its upstream regulatory region.

The gene encoding Aedes albopictus ribosomal protein L8 was isolated using a cDNA probe. Based on the deduced amino acid sequence, rpL8 has a mass of 28,605 Da, a pI of 11.97, and contains 9.6% Arg and 11.9% Lys. The rpL8 gene spans 1229 nucleotides, and contains three exons measuring 73, 150, and 648 nucleotides. The first intron is 293 nucleotides long and interrupts an 85-nucleotide untranslated leader sequence. The AUG codon is located 12 nucleotides downstream of the 5'-end of the second exon. Separating the second and third exon is a 65-nucleotide intron. The major transcription initiation site, identified by primer extension and polymerase stop reactions, mapped 378 nucleotides upstream from the AUG start codon; minor initiation sites were also detected. The DNA sequence upstream of the rpL8 gene was T-rich, but conventional TATA and CAAT boxes were absent. This is the first molecular analysis of a mosquito ribosomal protein gene.

Aedes↗
PubMed1990

Small heat shock proteins distinguish between two mosquito species and confirm identity of their cell lines.

We have adapted Aedes aegypti cells to Eagle's minimal medium containing nonessential amino acids, glutamine, and 5% fetal bovine serum. In this medium, cells maintained at 28 degrees C under a 5% CO2 atmosphere had a doubling time of 42 hr. Ninety-three percent of the cells in a typical population contained 6 full-size chromosomes and an apparent chromosome fragment. Ae. aegypti cells could be distinguished from Ae. albopictus cells by the sizes of the small heat shock proteins, whose synthesis was induced by a brief treatment at 41 degrees C. Analysis of the small heat shock proteins synthesized by dissected ovaries from Ae. aegypti and Ae. albopictus confirmed the species of origin of the 2 cell lines.

Aedes↗
PubMed1989

[Clinical features and X-ray manifestations of mucopolysaccharidosis-II-B].

Mucopolysaccharidosis-II (MPS-II) and MPS-I are both characterized by gargoylist dwarfism. MPS-II is of X-linked recessive heredity. Five cases of MPS-II-B in our series were followed up for ten years. Corneal opacity and dysmnesia were not found in all of them. Although MPS-II possessed many radiologic similarities to MPS-I, the former presented certain characteristic features such as butterfish-like vertebra, and small triangular malformation of carpal bones and tarsal scaphoid etc.

Adolescent↗
PubMedDate not supplied

Detection of p53 protein accumulation in sputum and lung adenocarcinoma associated with indoor exposure to unvented coal smoke in China.

Lung cancer in Xuan Wei (XW), China has been linked to exposure to unvented coal smoke and adenocarcinoma, especially bronchioloalveolar carcinoma, is most common. p53 mutations occur commonly in lung cancers and usually generate detectable levels of p53 protein accumulation. Sputum is noninvasive to collect and ideal for screening p53 abnormalities. p53 protein accumulation was detected by immunohistochemistry in lung tumors and sputa from XW lung cancer patients to determine (1) the role of p53 in lung pathogenesis, and (2) feasibility of detecting p53 protein accumulation in sputum, p53 protein accumulation was detected in 73% (22/30) of lung adenocarcinomas from XW females exposed to coal emissions and significantly higher than the control cases (33%, p < 0.05). In sputum, we detected p53 overexpression in tumor cells in 54% (13/24) of XW cases and also in dysplastic cells (50% or 4/8). These findings suggest that p53 abnormalities is important in XW lung cancer etiology.

Adenocarcinoma↗
PubMedDate not supplied

A sensitive immunofluorescence assay for detection of p53 protein accumulation in sputum.

p53 mutations are common genetic alterations in lung cancers and usually result in p53 protein accumulation in tumor cells. Sputum is noninvasive to collect and ideal for screening p53 abnormalities. This study was to determine the feasibility of detecting p53 protein accumulation in sputum cells using an immunofluorescence assay. Sputum samples were collected from 58 Chinese subjects, including 16 lung cancer cases from Xuan Wei (XW) County exposed to coal smoke, 25 mostly tobacco smoke-related cases from Zhengzhou City, and 17 XW controls. The p53 protein accumulation in tumor cells and some atypical cells was detected in 56% (9/16) of the coal smoke-exposed XW cases, 44% (11/25) of the Zhengzhou cases and none (0/17) in controls. The p53+ tumor cells were confirmed morphologically by Papanicolaou staining after the p53 immunofluorescence assay. This is the first report of successfully using an immunofluorescence assay to detect p53 protein accumulation in sputum.

Adenocarcinoma↗