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Biomedical subjects

Yan Zhao

Publications and source records attributed to Yan Zhao.

At least 163 records · Page 9Linked to original sources
PubMed2004

[Time tendency and its cohort study of leukemia mortality of residents in Urumqi].

To explore the distribution of leukemia mortality and its relationship with age of residents who live in city Urumqi, data of leukemia mortality of Urumqi residents from 1985 years to 2000 years was analysed. On the basis of multiple cross-sectional analysis,a cohort study was applied to further analysis. The results showed that the total mortality and male's mortality of leukemia in Urumqi residents were almost the same as that of national level, while the female's mortality of leukemia was lower than that of national level. The cohort study showed that mortality of adolescent with leukemia descended with the increase of age, but mortality of gerontic leukemia ascended with the increase of age. In conclusion, there is a significant relationship between the morbific age of leukemia and prognosis of patients with leukemia.

Adolescent↗
PubMed2004

[Detection of HPV 58 and cloning of its E7 gene in cervical cancer].

OBJECTIVE: To detect HPV 58, a common type of human papillomavirus (HPV), clone and express its E7 gene from biopsy specimens of cervical cancer. METHODS: HPV 58 from 58 biopsy tissues of cervical cancer was detected by GP5+/GP6+ PCR followed by template-directed dye-terminator incorporation assay with fluorescence polarization detection (TDI-FP). HPV 58 E7 gene was amplified from one HPV 58-positive sample, and then cloned into pGEM-T Easy vector. The recombinant plasmid, HPV58E7-pGEM-T was confirmed by sequencing. Subsequently, E7 gene was cloned into prokaryotic expression vector pRSET-A. The constructed pRSET-58E7 plasmids were transfected into BL21(DE3) cells, and induced to express 58 E7 protein by IPTG. RESULTS: Among the 58 biopsy tissues of cervical cancer, 10 were HPV 58-positive, accounting for 19.2% of 52 HPV-positive cases. HPV 58 E7 gene was amplified from one HPV 58-positive sample. The constructed plasmids were identified containing HPV58 E7 gene by restriction enzyme analysis and sequencing. SDS-PAGE analysis showed that HPV58 E7 His6 fusion protein of M(r) 16 x 10(3) was expressed by pRSET-58E7 after induction by IPTG. The fusion protein accounted for 30% of total bacterial proteins. CONCLUSION: HPV 58 is not uncommon in Chinese women with cervical cancer in Shaanxi province. Constructed HPV58 E7 recombinant plasmids can be effectively expressed in E.coli, which may provide a tool in diagnosis and vaccine design for HPV of HPV58-associated tumors.

Adult↗
PubMed2004

[Phonation reconstruction and function assessment after total and near-total laryngectomy].

BACKGROUND & OBJECTIVE: Total laryngectomy is a common surgery pattern for treating laryngeal and hypopharyngeal cancer, but patients will lost phonation function after operation. This study was to retrospectively analyze usage of modified Amatsu, and modified Pearson operation in treating laryngeal and hypopharyngeal cancers, and to analyze phonation function by subjective and objective assessment. METHODS: Clinical data of 69 patients with laryngeal or hypopharyngeal cancer treated by total or near-total laryngectomy (modified Amatsu or modified Pearson operation) in our department from 1996 to 2003 were retrospectively analyzed. Phonation function of 69 patients was evaluated by acoustic analysis and Jiyan classification method, and compared with phonation quality of patients received vertical hemilaryngectomy (VHL) and healthy people. RESULTS: No patient appeared obvious aspiration. Four cases with post-operative radiotherapy all regained phonation function. The 3-year survival rate was 88% (22/25); 5-year survival rate was 80% (4/5). Results of acoustic assessment, and Jiyan classification method indicated that phonation function of patients received modified Amatsu or modified Pearson operation could meet daily requirements. CONCLUSIONS: Modified Amatsu and modified Pearson operations can be learnt and applied easily for phonation reconstruction after laryngectomy. They may be optional surgery patterns, especially modified Pearson operation.

Adult↗
PubMed2004

[Analysis on origin and evolution of mumps].

There was a preliminary recognition on mumps during the Qin-Han to Sui-Tang dynasty, laying a foundation for the scholastic development on this topic in later generations. The title of this disease was identified in Song-Jin-Yuan dynasty with gradual deepening on its principle-method-formula-medication system, a great progress of recognition as compared with the previous ages. In the Ming-Qing dynasty, the recognition became even more systematic, with certain breakthrough in the system of principle-method-formula-medication. In modern age, the experiences were inherited and developed to integrate to modern biomedicine, so that the theory and clinical practice become even more perfect.

History, Ancient↗
PubMed2004

[Construction of phage display antibody library to MCF-7 cells and screening of single-chain antibodies against breast cancer cells].

The aim of this study is to construct a phage display single-chain variable fragment (scFv) library against breast cancer cells and screen the specific antibodies against MCF-7 cells from the library. The BALB/C mice were immunized with MCF-7 cells. Total RNA of spleens was isolated. The heavy-chain (VH) and light-chain variable region genes (VL) of the antibodies were amplified by RT-PCR and joined into a single chain by overlapping PCR with a linker DNA encoding the peptide (Gly4Ser)3. The assembled scFv fragments were cloned into the phagemids(pCANTAB5E) and the recombinant phagemids were used to transform competent E. coli TG1. The transformed TG1 cells were infected by helper phage M13KO7 and the recombinant phagemids were rescued. The scFv fusion proteins were displayed on the surfaces of the recombinant phages. A phage display antibody library of repertoire of 1.2 x 10(6) clones was constructed. The specific antibodies against MCF-7 cells were enriched by 75 times after five rounds of affinity selection. Ten recombinant phages clones that exhibited specific binding to MCF-7 cells were identified. The specificity of those phage clones was analyzed by reactivity against HepG2 cells and Hela cells by ELISA. One of the selected phage clones against MCF-7cells was used to infect E. coli TOP10 to produce the soluble scFv antibodies after induction with IPTG. The strategy of construction and screening of antibody library directed against the whole tumor cells described in this report should be generally applicable to generate tumor cell-specific antibodies.

Animals↗
PubMed2003

Sodium tanshinone IIA sulfonate mediates electron transfer reaction in rat heart mitochondria.

In this paper, an electron transfer reaction mediated by sodium tanshinone IIA sulfonate (STS) was studied in rat heart mitochondria. It was found that STS could stimulate mitochondrial NADH oxidation dose-dependently and partly restore NADH oxidation in the presence of respiratory inhibitor (rotenone or antimycin A or KCN). It was likely that STS could accept electrons from complex I similar to ferricyanide and could be converted to its semiquinone form that could then reduce oxygen molecule. The data also showed that cytochrome c (Cyt c) could be reduced by STS in the presence of KCN, or STS could transfer the electron to oxygen directly. Free radicals were involved in the process. The results suggest that STS may protect ischemia-reperfusion injury through an electron transfer reaction in mitochondria against forming reactive oxygen radicals.

Animals↗
PubMed2003

Brick tea fluoride as a main source of adult fluorosis.

An epidemiological survey was conducted in Naqu County, Tibet in September 2001 to investigate the manifestations of fluorosis in adults caused by the habitual consumption of brick tea. Profiles were obtained for the total daily fluoride intake, environmental fluoride levels and average urinary fluoride concentration, and a physical examination and a skeletal radiographic study were conducted. One hundred and eleven 30-78-year-old adults were enrolled. It was found that the fluoride level of water sources in Naqu County was 0.10+/-0.03 mg/l; no evidence of fluoride air pollution was found, but the brick tea water processed foods--zamba and buttered tea--had fluoride contents of 4.52+/-0.74 mg/kg and 3.21+/-0.65 mg/l, respectively. The adult daily fluoride intake reached 12 mg, of which 99% originated from the brick tea-containing foods. The positive rate of clinical symptoms by physical examination was 89%; furthermore, 42 of the 111 subjects were diagnosed by X-ray. The positive examination rate was 83%. Although the osteosclerosis-type skeletal fluorosis (overall increased bone matrix density) affected 74%, arthropathy and arthritis affected a significant number of the patients, resulting in functional disability. The results suggest that this brick tea-type fluorosis had even more severe adverse effects on human health compared with both the water-type and coal combustion-type fluorosis that occurred in other areas of China.

Adult↗
PubMed2003

Folate biosynthesis pseudogenes, PsifolP and PsifolK, and an O-sialoglycoprotein endopeptidase gene homolog in the phytoplasma genome.

Phytoplasmas are wall-less phytopathogenic prokaryotes of small genome sizes that are obligate parasites of insect vectors and plant hosts. We have cloned a clover phyllody (CPh) phytoplasma DNA locus containing five potential coding sequences. Two were identified as pseudogenes (PsifolP and PsifolK) homologous to folP and folK genes, which encode dihydropteroate synthase (DHPS) and 6-hydroxymethyl-7,8-dihydropterin pyrophosphokinase (HPPK), respectively, in other bacteria. Evolution of the phytoplasma presumably involved loss of functions through the formation of these and other pseudogenes during adaptation to obligate parasitism. The findings suggest that the phytoplasma lacks capacity for de novo folate biosynthesis and possesses a transport system for absorption of preformed folate from host cells. The PsifolP-PsifolK region was flanked by three open reading frames (ORFs) encoding a DegV family protein, a hypothetical protein with a P60-like lipoprotein domain homologous with the P60-like Mycoplasma hominis protein, and a glycoprotease (Gcp) protein that possibly functions as a host adaptation or virulence factor.

Amino Acid Sequence↗
PubMed2003

[Effect of beta-carotene on gene expression of breast cancer cells].

BACKGROUND & OBJECTIVE: This study was conducted to investigate the altered gene expression of MCF-7 cell before and after the treatment with beta-carotene using cDNA microarray and to investigate the mechanism which beta-carotene induce breast cancer cell apoptosis. METHODS: Two fluorescence cDNA probes were made using reverse transcriptional reaction from mRNA of beta-carotene untreated or treated MCF-7 cells (human estrogen receptor positive breast cancer cells), marked with two different fluorescence dyes (cy3 and cy5) respectively, hybridized with expressed cDNA microarray scanned and analyzed by computer system and finally the expressed gene was produced. RESULTS: A total of 21 genes related to cell apoptosis, cell signal transduction, protein translation and immunity were expressed differently after the treatment of beta-carotene, which 3/21 were up-regulated (AF040958, AK001555,g41894),18/21 were down- regulated(hshsp90r,U83857,AB014509,AF126028,AF053641,AF117386,AF050127,NM_012177,humtopi,AJ250915,U37547,U78798,NM_004849,NM_005346,AF004711,NM_006595,NM_001418,AB015051). CONCLUSION: beta-carotene may inhibit the growth of breast cancer cells through inducing apoptosis,breaking signal transduction,and blocking protein translation.

Antioxidants↗
PubMed2003

[Cotransformation of rice by bar and cecropin B gene expression cassettes lacking vector backbone sequences].

Whole plasmids are used in both Agrobacterium-mediated transformation and direct DNA transfer, generally leading to the integration of vector backbone sequences into the host genome along with the transgene(s). The undesirable vector backbone sequences may not only promote transgene rearrangements and affect transgene or endogenous gene expression negatively, but have disadvantage on the safe assessment of the transformants as "desert DNA". The direct DNA transforming systems can transfer minimal gene expression cassettes (promoter, open reading frame, terminator) into plant genome and generate "safer" transformants, also it can delivery multiple genes of agronomic relevance to economically-important crop plants. But there is seldom researching reports on the topic till now. The present paper studied some factors that affecting the transforming efficiency of liner gene expression cassettes to rice varieties by particle bombardment, and the integration patterns of the gene expression cassettes in rice genome were compared with that of the whole plasmids. The results showed: (1) The transforming frequency of gene expression cassettes to rice via particle bombardment is 0.1%-0.5%, the cotransforming frequency of non-selectable gene is about 50%-60% when two separate gene expression cassettes were used for transformation. Increasing the DNA mole content can increase the transforming frequency and the beside sequences of gene constructs may play an important role on the variation of transforming efficiency between different rice varieties. (2) It's reported that the selectable and non-selectable transgene expression cassettes generated low-copy-number transgenic plants with simple integration patterns. While our results showed that the non-selectable cecropin B gene cassette generated simple integration patterns with 1-3 copies in the rice genome, but the selectable bar gene cassette which got 4-14 copies had much more complex integration patterns than that of the whole plasmids which got 1-3 copies only. As the bar gene is promoted by the CaMV35 promoter, in which there is a 19 bp palindromic sequence could act as recombination hot spot and lead to DNA rearrangement, we presumed that the transgene recombination events happened during the integration course have generated the complex Southern patterns of bar gene expression cassette. The recombination character, the heredity behavior and the expression law of gene expression cassettes in the rice genomes will be reported in our future papers.

Acetyltransferases↗
PubMed2003

[Clinical and pathological features of borderline ovarian tumors].

OBJECTIVE: To study the relationship between clinical pathological factors and prognosis. METHODS: Thirty-four cases with borderline ovarian tumors (BOT) and 30 cases with stage I ovarian epithelial cancer admitted in our hospital from Jan.1973 to Dec.2000 were studied retrospectively. All the cases were diagnosed according to the International Histological Classification and Staging of Ovarian Tumors (WHO, 1999). RESULTS: Thirty-seven cases were finally diagnosed of BOT, 6 cases with "microinvasive" had been misinterpreted as stage I ovarian cancer and one had "non-invasive peritoneal implants". Serous (38%) and mucinous (51%) tumors were dominant type of BOT and 95% of tumors were at stage I (International Federation of Gynecology and Obstetrics, FIGO). All patients were operated, 11 cases given conservative surgery with a recurrence rate of 9%, 26 cases had adjuvant chemotherapy, cyclophosphamide + adriamycin + cis-platinum used mostly. 5-year and 10 year survival rates were both 100%. The prognosis of BOT is related to pathology and adjuvant therapy. CONCLUSION: Surgery is the main treatment choice of BOT, and the criteria of chemotherapy must be adequately used.

Adolescent↗
PubMed2003

[Brick-tea type adult bone fluorosis].

To investigate health impact of brick-tea type fluorosis in adults, the total daily fluorine intake, environment fluorine level were determined, the average urinary fluorine content assay and bone X-ray examination were conducted, the clinical manifestations were observed in the brick-tea type bone fluorosis epidemiological study conducted in Naqu County, Tibet at September, 2001. One hundred and eleven adults aged at 30-78 year-old were enrolled. It was found that the fluorine level of drinking water in Naqu County was 0.10 +/- 0.03 mg/L, but the brick-tea water processed foods-zamba and buttered tea had fluorine content of 4.52 +/- 0.74 mg/kg and 3.21 +/- 0.65 mg/kg respectively. The adult daily fluorine intake reached 11.99 mg, among which 99% is originated from the brick-tea containing foods. Positive detection rate of fluorosis osteopathy was 89% and the X-ray film confirmed that the diagnosis rate was 83%. Degenerative arthropathy and ossification of the interosteal membrane, calcification of the tendon were the characteristics that indicated by both the positive signs and reogenological examination. The prevalence of osteosclerosis type (bone matrix increased) was 74%. It is suggested that there were even more severe health impact compared with those in the water type and coal combustion type fluorosis.

Adult↗
PubMed2003

[Detection of bacterial 16S rRAN gene in EPS of men with chronic pelvic pain syndrome and its clinical significance].

OBJECTIVES: To investigate the cause of chronic pelvic pain syndrome (CPPS) and the correlation between presence of bacterial signal and the response to antibiotics by detecting bacterial 16S rRNA gene signal using polymerase chain reaction (PCR). METHODS: EPS and first void urine (VB1) from 59 men with CPPS were analyzed by PCR for bacterial signal using universal primers specific for bacterial 16S rRNA gene. If the bacterial signal was found only in EPS or the EPS bacterial signal was at least 10 times stronger than the VB1 one, positive result could be decided for bacterial signal detection. All patients were treated with levofloxacin and azithromycin for 4 weeks. The treatment could be considered effective if more than 50% improvement, compared to the state before the treatment, was achieved in the symptom severity index(SSI), symptom frequency questionnaire(SFQ), national institutes of health chronic prostatis symptom index of pain(quasi-CPSI) or the patients' general subjective assessment. RESULTS: Positive bacterial signal was detected in 46 of the 59 CPPS patients; The difference of improvement rates between positive bacterial signal group and negative bacterial signal group, which were 65%-74% and 0 respectively, was significant. CONCLUSIONS: The basis of detecting 16S rRNA gene signal by PCR in clinical practice was built. The study shows that bacterial infection is related to CPPS. Bacterial signal detection results can help predict the effect of antimicrobial therapy.

Anti-Bacterial Agents↗
PubMed2003

[A preliminary study on the treatment of severe autoimmune disease by autologous peripheral CD(34)(+) cell transplantation].

OBJECTIVE: To evaluate the feasibility of autologous peripheral CD(34)(+) cell transplantation for the treatment of severe autoimmune disease. METHODS: Ten patients received mobilized and purified CD(34)(+) cells transplantation. The mobilization regimen was CTX plus rhG-CSF and the CD(34)(+) cells were selected by CliniMACS. (1.98 +/- 0.95) x 10(8) CD(34)(+) cells were obtained. The purity of CD(34)(+) cells was (91.4 +/- 10.6)% and the recovering rate was (60.5 +/- 19.8)%. The conditioning regimens were CTX (200 mg/kg) plus ATG (90 mg/kg) or CTX (150 mg/kg) plus TBI (4 - 6 Gy). (2.14 +/- 1.05) x 10(6)/kg CD(34)(+) cells were infused. The time of ANC >or= 0.5 x 10(9)/L was 8.6 +/- 2.5 days, and platelet >or= 20 x 10(9)/L was 9.0 +/- 5.2 days. After the hematopoietic recovery, the levels of CD(3)(+) T cell, CD(19)(+) B cells and CD(16)(+)CD(56)(+) NK cells were all below that of pre-transplantation. The main transplant-related complication was CMV infection. The transplant-related mortality was 2/10. All patients who survived showed improvement of the disease with DAI score decreasing from 17 to 4 in systemic lupus erythematosus patients, DAS 28 score from 6.4 to 1.8 in rheumatoid arthritis patients. CONCLUSION: The result suggests that autologous peripheral CD(34)(+) cell transplantation is an alternative choice for the treatment of severe autoimmune disease. The short-term outcome is satisfying.

Adolescent↗
PubMed2003

[Abnormal interferon-inducible protein-10 expression in the labial glands of patients with Sjogren's syndrome].

OBJECTIVE: To investigate whether interferon-inducible protein 10 (IP-10) is involved in the inflammatory process of the labial gland of patients with Sjogren's Syndrome (SS). METHODS: Forty-nine patients performed labial gland biopsy, the number of lymphocytes in the biopsy tissues was calculated and the IP-10 was detected by the methods as following: 39 biopsied labial tissues were examined by RT-PCR, among them, 21 were from primary SS, 5 from secondary SS and 13 from other diseases. With RT-PCR, the IP-10 and beta-actin were co-amplified with specific primers. The gel-fractioned and ethidium bromide amplification products were then analyzed by densitometry. The expression of IP-10 was semi-quantificated by IP-10/beta-actin ratio. Twenty-one samples were examined by immunohistochemistry with specific goat anti-IP-10 antibody, 10 of them from primary SS, 3 from secondary SS, 8 from other diseases. 11 out of 21 samples were examined by both RT-PCR and immunohistochemistry. RESULTS: The expression of IP-10 mRNA was significantly up-regulated in labial glands of patients with SS compared with other diseases (IP-10/beta-actin ratio was 0.329 +/- 0.157 vs 0.099 +/- 0.059, P < 0.01). The number of lymphocyte infiltration foci in labial glands of patients with SS correlated to the IP-10/beta-actin ratio (r = 0.657, P < 0.05). Ductal epithelial cells and some of the infiltrating lymphocytes were stained by anti-IP-10 antibody by immunohistochemistry in 8 of the primary SS (8/10), all of the secondary SS (3/3) and one with primary biliary sclerosis (1/8). The expression of IP-10 protein detected by immunohistochemistry was consistent with that of mRNA detected by RT-PCR. CONCLUSIONS: IP-10 is abnormally highly expressed in the labial glands of patients with SS and positively relates to the lymphocyte infiltration. It thus suggests chemokine IP-10 may be one of the important molecules attracting the lymphocytes to the minor salivary glands to form the lymphocytic foci of Sjogren's Syndrome.

Adult↗
PubMed2003

[Changes of myocardial enzymes in patients with acute carbon monoxide poisoning].

OBJECTIVE: To study the clinical significance of changes of serum myocardial enzymes in patients with acute carbon monoxide poisoning. METHODS: To determine the dynamic changes of the activity of myocardial enzymes and ECG in 62 patients with acute CO poisoning. RESULTS: In patients with acute CO poisoning 5 kinds of myocardial enzymes begin to increase within 24 hours, the activities of aspartate aminotransferase (AST), creatine phosphokinase (CPK), lactic dehydrogenase (LDH), alpha-hydroxybutyrate dehydrogenase (alpha-HBDH), CPK isoenzyme (CK-MB) were (20.2 +/- 12.3), (151.6 +/- 91.8), (146.8 +/- 50.4), (154.8 +/- 47.7), (13.8 +/- 8.1) U/L respectively, while those in control group were (12.1 +/- 6.7), (90.6 +/- 17.3), (118.7 +/- 13.5), (89.9 +/- 27.9), (5.9 +/- 3.3) U/L respectively. There was significant difference between two groups (P < 0.01); 3 d later, the activities of 5 enzymes were still increased [(21.3 +/- 12.3), (105.8 +/- 51.4), (144.8 +/- 51.4), (159.8 +/- 35.4), (16.2 +/- 9.1) U/L respectively]. 7 and 12 d later, the activities of alpha-HBDH and CK-MB were still higher than those of control (P < 0.01). LDH(1) and LDH(2) increased to peak value in 24 h after poisoning (35.3 +/- 5.8), (43.8 +/- 5.7) U/L vs (24.8 +/- 3.9), (36.9 +/- 4.3) U/L, P < 0.01. The abnormal rate of serum LDH(1) was 78.7%, LDH(2) 58.3%, LDH 45.2%, CK-MB 37.1%, alpha-HBDH 33.6% and the abnormal rate of ECG was less than 10%. CONCLUSION: Acute carbon monoxide poisoning may cause myocardial injury. Determination of serum myocardial enzymes may contribute to showing myocardial injury, early diagnosis and treatment, results of treatment and prognosis.

Adult↗