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Biomedical subjects

X Zhou

Publications and source records attributed to X Zhou.

At least 451 records · Page 25Linked to original sources
PubMed1998

HMGI family proteins: architectural transcription factors in mammalian development and cancer.

The HMGI proteins, a subfamily of the high mobility group (HMG) proteins, play an important role in the regulation of gene expression. They bind to AT-rich DNA sequences and alter DNA conformation to modulate the binding affinity of transcription factors to their cognate sites. They are expressed almost exclusively during embryogenesis and Hmgi-c null mice have the mouse pygmy phenotype. Studies have revealed the disruption of HMGI family genes in a variety of mesenchymal-derived benign tumors. Therefore, the HMGI genes function in the coordination of cell proliferation and differentiation during mammalian development.

Amino Acid Sequence↗
PubMed1998

A cryptic 19-kilobase plasmid associated with U.S. isolates of Yersinia pestis: a dimer of the 9.5-kilobase plasmid.

Yersinia pestis, the etiologic agent of plague, carries three prototypic plasmids with sizes of 110 kb (pFra, pTox), 70 kb (pLcr, pVW, pCad), and 9.5 kb (pPla, pPst). Studies suggest that geographic isolates of Y. pestis may be differentiated by plasmid profiles. Yersinia pestis isolated from the western United States harbor an additional plasmid, estimated to be approximately 19 kb in size. This cryptic plasmid was characterized by restriction endonuclease digestion, amplification and sequencing of the plasminogen activator gene segment, Southern blotting, and visualized by electron microscopy. Results revealed that this cryptic plasmid is a supercoiled DNA plasmid, 18.85+/-0.59 (mean+/-SD) kb in length, and is a dimer of the 9.5-kb plasmid. The genetic reason for the appearance of this form of the 9.5-kb plasmid in Y. pestis from Arizona, California, Colorado, New Mexico, and Texas is under study.

Animals↗
PubMed1998

[Microsurgical repair of the defect with large area of bare tibia].

OBJECTIVE: To study the best method in repairing the defect with a large area of bare tibia. METHOD: Three hundred and twenty-two cases of large bare tibia defects were treated by three microsurgical methods. RESULTS: The bare tibiae in the 322 cases ranging from 12 x 3 cm to 24.0 x 3.5 cm were covered with myocutaneous flaps. Primary wound healing was achieved in 300 cases and delayed healing in 22 cases. All the cases were followed-up for 1 to 5 years. The function of the lower limbs was evidently improved. None of them was amputated due to deficit of skin coverage. The patients were all satisfied with the operative results. CONCLUSION: Transposition of the bridging skin flap pedicaled with the contralateral posterior tibial blood vessels can cover extensive bare tibia to avoid amputation. Other myocutaneous flaps from thoraco-umbilical, tensor muscle of fascia lata and scapular-lateral chest areas are good options too.

Accidents, Traffic↗
PubMed1998

[Open heart surgery without cross clamping aorta].

Open heart surgery without cross clamping aorta under normothermic or hypothermic cardiopulmonary bypass was performed in 167 patients in which there were more than ten kinds of cardiac diseases. The characteristics of the procedure included only vena cava blocked and aorta unclamped with beating heart or artificial evoked ventricular fibrillation. It diminished myocardial ischemia and reperfusion injuries maximally. There were no low cardiac output syndrome, severe arrhythmia and complications of brain except two patients died postoperatively. The operative mortality rate was 1.1% (2/167). The advantages, disadvantages and safety of this method are discussed briefly in this paper.

Adolescent↗
PubMed1998

[A clinicopathological analysis of 15 cases with congenital tumors in fetus and newborn].

OBJECTIVE: The incidence rate of congenital tumors in fetuses and neonates and its influence on fetal outcome including development and death were analysed. METHODS: Both clinical manifestations and pathological data of 15 cases with congenital tumor were analysed retrospectively. RESULTS: The incidence rate of congenital tumors in fetuses and neonates was 7.7/100,000 with a rate of 0.7% in total perinatal autopsies. The most common tumor was teratoma (46.7%), the next was hemangioma (26.7%). Among 15 cases with congenital tumor, 9 cases (60.0%) were complicated with polyhydroamnios; 11 perinates (73.3%) were born with body weight appropriate for gestational age, 6 perinates (40.0%) were associated with various anomalies which were commonly secondary to the tumors. The common causes responsible for death were malformation, placental impairment due to tumor invasion or tumor grown at a special site. CONCLUSION: The incidence rate of congenital tumors in fetuses and neonates was very low. Because the tumor usually exhibited a local effect, under carefully evaluating the development of neonates, it is promising to get complete cure.

Adult↗
PubMed1998

[The relationship between the pathological classifications and molecular genetics of hydatidiform moles].

OBJECTIVE: To study the relationship between the pathological classification and molecular genetics of hydatidiform mole. METHOD: 32 cases of hydatidiform mole were analyzed by DNA restriction fragment length polymorphism (RFLP, hybridized with the probe 33.15). RESULTS: DNA from only paternal origin was found in 21, and from both parents in 11. In the formeron the basis of pathological characteristics, the complete hydatidiform mole (CHM) and the partial hydatidiform mole (PHM) were 16 (76%, 16/21) and 5 (24%, 5/21) respectively, and in the later CHM and PHM were 5 (45%, 5/11) and 6 (55%, 6/11), respectively. CONCLUSION: There is not much correlation between pathological classification and molecular genetics of hydatidiform mole.

Female↗
PubMed1998

[The method for the determination of fluoride in the total diet study].

This paper reports a microdiffusion method using fluoride-ion selective electrode for determination of fluoride contents in dietary samples. The method was suitable for the determination of fluoride in different dietary samples. It was a simple and fast method, and could be applied in large amount of sample analysis. The minimum detectable limit of this method was 1.0 microgram fluoride in 1.0 g dry dietary sample. The range of fluoride recovery and RSD in this dietary samples were 85.0%-107.0% and 4.5%-9.5% respectively. The fluoride content determined in the oyster tissue of NBS 1566 SRM was 87.9%-104.6% of certified SRM, and RSD was 6.5%. The RSD of fluoride determination in alcohol drinks was 3.1%.

Diet Surveys↗
PubMed1998

[The effect of electroacupuncture stimulation an neurotrophic substance in cat spinal dorsal horn].

For exploration of the mechanism of collateral sprouting from injured spinal cord, polyacrylamide gel electrophoresis (PAGE) and modified hanging drop culture method were used to examine the effect of acupuncture on the amount and the biological activity of neurotrophic substance in larger than 50 kd fraction of dorsal horn in cat subjected to partial dorsal rhizotomy. The results showed that the amount of protein in relative mobility (RM) 0.1 zone increased significantly in the acupuncture-operated group by PAGE and that of protein in RM 0.5 zone decreased significantly as compared with the unoperated group. While this data was compared with the data of another operated group in our lab, the amount of RM 0.1 protein of the acupuncture-operated group was significantly higher than that of the latter group; however, no obvious difference was noted between the two groups in the amount of RM 0.5 protein. It suggests that acupuncture may promote tha amount of RM 0.1 protein to increase, but acupuncture has no influence on the amount of RM 0.5 protein. Also, the results showed that, in culture, accompanying with the increase in amount, the activity of RM 0.1 protein for promoting DRG neurite-outgrowth increased. This indicates that the RM 0.1 protein has a function to promote DRG neurite-outgrowth, but the RM 0.5 protein has no obvious effect on DRG neurite-outgrowth.

Animals↗
PubMed1998

[Expression of glial cells line-derived neurotrophic factor in the central nervous system of rat].

Glial cell line-derived neurotrophic factor (GDNF) iss a distant member of the transforming growth factor-beta, originally isolated by virtue of its ability to induce dopamine uptake and cell survival in cultures of embryonic ventral midbrain dopaminergic neurons, and more recently it has been shown to be a potent neurotrophic factor for motor neurons. However, the distribution of this molecule in the central nervous system (CNS) is not known yet. In the present study, the expression of GDNF of rat was investigated by using immunohistochemistry. GDNF immunoreactive fibers or bodies were found in molecular layer and Purkinje layer of cerebellum. In the spinal cord, neuronal expression was found widely, especially in ventral horn, Clarke's column. GDNF was also expressed in fiber terminals of I and II lamella of dorsal horn. Additionally, GDNA expression was found in the ependymal epithelium and neuroglia of spinal cord. The nuclei of neuroglia were stronger than perikaryon. The neurons in cerebral cortex showed very weak immunoreaction. We conclude that GDNF is expressed in many different cellular systems within the CNS, suggesting the multiple functions of GDNF in the adult CNS.

Animals↗
PubMed1998

[Study on the health of cotton mill workers].

A group of 110 workers in a cotton mill was investigated by questionnaire, skin testing, and the measurement of airway responsiveness through forced expiratory volume for one second(FEV1) by spirometry. The workers were examined before starting work, 10 weeks and one year after exposure. Decreases in FEV1 over shifts were small at 10 weeks and one year, and were slightly higher among people with positive skin reactions to cotton dust extracts. Airway responsiveness, defined as the average decrease in FEV1 after 1.25 mg methacholin, was increased at 10 weeks. It remained about the same after one year, except in the workers with positive skin test. Subjective symptoms of chest tightness and cough with phlegm increased progressively at 10 weeks and one year. Nasal irritation remained unchanged and dry cough decreased in one year. The results suggest that the airway inflammation caused by cotton dust increases with the exposure time and that the changes are more notable in workers with reactivity to cotton dust extract.

Adolescent↗
PubMed1998

[Isolation, purification and activity measurement of proteolytic enzymes in dental plaque].

The purpose of this study was to investigate the types and activities of proteolytic enzymes in human root surface plaque. Sephadex G-200 gel filtration, fluorometry and spectrometry were used to isolate, purify and demonstrate the activities of proteolytic enzymes. The results indicated that three enzymes were present in the root surface plaque, namely leucine amino peptidase, dipeptidyl peptidase i.v. and trypsin-like proteinase, and their activities were different.

Aged↗
PubMed1998

[Radiotherapy combined with intervention treatment for patients with advanced cancer: a randomized study in 60 cases].

OBJECTIVE: To study methods of treatment for advanced cancers. METHODS: From January 1996 to March 1997, 60 patients with advanced cancers whose life expectancy was 3-6 months were randomly divided into two groups. The method of radiotherapy was the same in the two groups, with a dose of DT50Gy/25f/5wk for intra-abdomanal cancers while DT60Gy/30f/6wk for those in the other regions. In the combination treatment group, in addition to radiation, interventional therapy with chemotherapeutic drugs, biological response modifiers or Chinese medicinal herbs was employed. RESULTS: The response rate, mean remission period, median survival time and 1-year survival rate in the combination treatment group was 98.3%, 7.4 months, 11 months and 46.7%, respectively. All these were significantly different from those in the group of patients treated with radiation alone. (63.6%, 4.7 months, 6.5 months and 6.7%, respectively, P < 0.01). CONCLUSION: Radiotherapy combined with intervention treatment can prolong the survival time and improve quality of life in patients with advanced cancer.

Adult↗
PubMed1998

[Detection of Epstein-Barr virus subtypes in Hodgkin's disease].

OBJECTIVE: To investigate Epstein-Barr virus (EBV) subtypes in Chinese patients with Hodgkin's disease (HD). METHODS: 113 cases of HD patients with EBV latent membrane protein 1 (LMP-1) and/or EBV encoded small RAN (EBER-1) positive and throat washings from 21 healthy persons were studied for EBV subtypes by polymerase chain reaction (PCR). RESULTS: 68 HD cases exhibited specific bands, in which 62 cases were EBV type A and 6 cases were EBV type B. 13 of the control washing gave rise to specific bands, of which 11 were EBV type A and 2 of EBV type B. CONCLUSION: The results showed that EBV type A is predominant in Chinese HD patients and healthy individuals.

Adaptor Proteins, Signal Transducing↗
PubMed1998

[Microsatellite instability in gastric carcinoma and intestinal metaplasia].

OBJECTIVE: To investigate the role of microsatellite instability (MSI) in the carcinogenesis and development of gastric cancer (GC). METHODS: MSI was examined in 50 surgically resected gastric cancer specimens and 15 intestinal metaplasia specimens using PCR based methods. RESULTS: MSI was detected in 27/50 of GC and 3/15 of intestinal metaplasia at one or more loci. MSI was positive in all three cases of early GC. The incidence of MSI in well differentiated GC (86.6%) was significantly higher than that in poorly differentiated GC (P < 0.05). The frequency of MSI in intestinal type of GC (77.8%) was significantly higher than that in the diffused type (40%, P < 0.05). No significant correlation was found between MSI and age, sex, size, location, lymph node metastasis or clinical stage of GC. CONCLUSION: MSI is an early molecular marker in the carcinogenesis of GC and may play an important role in the development of GC.

Adenocarcinoma↗
PubMed1998

[CT images in differentiating tuberculous nodules from lung cancers with diameters less than 2 cm].

OBJECTIVE: To find out the CT characteristics of tuberculous nodules and lung cancers with diameters less than 2 cm, and to evaluate their value in differentiating the two diseases. METHOD: The CT images in thirty patients with tuberculous nodules and forty lung cancer patients with lesions less than 2 cm in diameter were compared. RESULTS: Smooth or clear edge, non-lobulation, small cavity, calcification, pleural thicking and adhesion, satellitic nidus and perifocal inflammation were found predominant in tuberculous nodules with short-term dynamic changes in shapes, while shaggy border, shallow lobulation, vacuolus sign, air-bronchogram and typical pleural indentation were predominant in lung cancers without dynamic changes in shapes. CONCLUSION: Thin-slice CT scanning can provide useful images, which by short-term observations are important for differentiating these diseases.

Adenocarcinoma↗