Search PubMed⌕ Search

Biomedical subjects

X Zhao

Publications and source records attributed to X Zhao.

At least 343 records · Page 19Linked to original sources
PubMed1999

[Clinical significance and expression of Bcl-2 protein in patients with systemic lupus erythematosus].

OBJECTIVE: To investigate the pathogenesis and clinical evaluation for expression of Bcl-2 in lymphocytes and renal tissues of 31 patients with systemic lupus erythematosus (SLE). METHODS: Bcl-2 protein levels in T, B cells and renal tissues were examined by two-colour cytofluorography, and immunohistochemical staining (LSAB method) respectively. RESULTS: Compared with inactive SLE patients and normal controls, a proposition of T cells (including CD(3)(+), CD(4)(+) and CD(8)(+) subgroups) expressing Bcl-2 protein increased significantly in active SLE patients. However, Bcl-2 protein levels are not statistically different in CD(19)(+) B cells among all groups. Mean fluorescence intensity (MFI) levels of Bcl-2 protein on CD(3)(+) T cells was positively related to SLE disease activity index (SLEDAI) among the SLE patients, which wasn't related to ESR, complement (C(3), C(4)) and autoantibody (ANA, anti-dsDNA, anti-Sm) positivity. The population of Bcl-2 positive intraglomerular cells was correlated significantly with the grade of mesangial cell increase and the number of proliferating cell nuclear antigen (PCNA) positive glomerular cells, and 24-hour urinary protein. CONCLUSION: Overexpression of apoptosis-related Bcl-2 protein might play an important rule in the prolonged proliferation of mesangial cells and glomerular hypercellularity and in the active period of SLE patients, Bcl-2 expression levels of peripheral blood T lymphocytes might serve as an active index for SLE.

Adult↗
PubMed1999

[Can esophagogastric anastomosis prevent gastroesophageal reflux].

OBJECTIVE: To investigate the possible anti-reflux function of esophagogastric anastomosis in the patients after receiving resection of cardiac cancer. METHODS: One hundred and ninety-two patients were studied by video-assisted gastroscopy, manometry, 24-h pH esophageal monitoring, radioscintigraphy and scanning electron microscopy. RESULTS: Abnormalities were found in 90.2% of patients through endoscopy. Resting pressure in esophageal body was higher than that in normal controls, and in the stomach, lower. Twenty-four hour pH monitoring demonstrated that gastroesophageal reflux (GER) did not occur when the patients slept in semi-reclining position, and occurred in all patients when slept in supine position. Scintigraphic study showed that 2/3 of the patients had reflux, occurrence of which was not affected by the length of postoperative period. Scanning electron microscopic examination showed that degeneration, exfoliation of esophageal mucosal epithelial cell, and derangement of micro-fold and inflammatory oedema of cytomembrane may be directly caused by reflux. CONCLUSIONS: GER exists in the majority of the patients after esophagogastrectomy and esophagogastrostomy for cardiac cancer. The occurrence of GER is not affected by the length of postoperative period. Some detecting methods fail to show the existence of GER, and 24-h pH monitoring is the most reliable method for detecting GER. Sleep in semireclining position is an effective method of preventing GER in postoperative patients.

Adult↗
PubMed1999

[Functional improvement of remnant stomach after proximal subtotal gastrectomy for cardiac cancer].

OBJECTIVE: To evaluate the function of the remnant stomach after proximal subtotal gastrectomy for cardiac cancer and to improve the life quality of post-surgical patients. METHODS: 17 patients with cardiac cancer underwent proximal subtotal gastrectomy combined with disconnection of pyloric sphincter (PSG + DPS) by finger pressing. Intraoperative pyloric manometric studies were performed in the 17 patients before and after DPS. Five subjects who underwent laparotomy for non-esophagogastric reasons was taken as controls. Total bile acids (TBA) in gastric juice was tested in the 17 patients at 5th postoperative day, and radionuclide gastric emptying was also studied from the 18th to 20st postoperative day. RESULTS: Both pyloric resting pressure and pyloric contracting pressure were significantly decreased after DPS (P > 0.01). In comparison with normal subjects, PCP was increased before DPS (P > 0.01) and decreased after the procedure (P < 0.05). However, PRP did not show significant differences before (P > 0.05) and after (P > 0.05) DPS. There were no significant differences regarding TBA content in gastric juice in PSG + DPS group, PSG group, and normal subjects (P > 0.05). The time required for the stomach to empty half of its radioactive contents (T1/2) was longer in the patients having PSG only than those undergoing PSG + DPS (P < 0.01) and normal controls (P < 0.05). However, there were no significant differences regarding T1/2 between the patients with PSG + DPS and normal controls (P > 0.05). CONCLUSIONS: The emptying of remnant stomach after subtotal gastrectomy for cardiac cancer is delayed because of the increase of emptying-resistance and decrease of peristalsis. PSG combined with DPS not only improves gastric emptying, but also prevents duodenogastric reflux. Consequently, postoperative life quality of the patients with cardiac cancer can be effectively improved.

Aged↗
PubMed1999

[Biopterin synthesis and GTP cyclohydrolase I mRNA expression in rats following endotoxic shock].

OBJECTIVE: To investigate the potential role of changes in biopterin (tetrahydrobiopterin and more oxidized species) synthesis and GTP cyclohydrolase I (GTP-CHI) mRNA expression in endotoxic shock. METHODS: SD rats were subjected to endotoxic shock by a bolus injection of lipopolysaccharide (15 mg/kg, i.p.), biopterin and GTP-CHI mRNA levels in liver, kidney, and intestine were determined at 4, 8 hours following endotoxin challenge. RESULTS: Tissue biopterin levels significantly elevated in liver, kidney, and intestine, with high levels sustaining for 8 hours after endotoxin challenge (P < 0.05, P < 0.01). Similarly, GTP-CHI mRNA induction in various tissues substantially increased within 4 hours compared to normal controls (P < 0.05, P < 0.01). It was also shown that hepatic and renal biopterin levels were positively correlated with glutamic pyruvic transaminase (GPT) and also blood urea nitrogen (BUN) values (both P < 0.01). In addition, treatment with recombinant bactericidal/permeability increasing protein (rBPI(21)) markedly reduced tissue biopterin and GTP-CHI mRNA levels, concomitant with significant decreases in GPT, BUN as well as D-lactate values. CONCLUSIONS: Biopterin synthesis and release may be involved in the development of endotoxin-induced multiple organ dysfunction, and early use of rBPI(21) is effective to inhibit marked GTP-CHI mRNA expression and biopterin formation following septic shock.

Animals↗
PubMed1999

[Effects of environmental lead exposure in kindergartens on children's blood lead level].

OBJECTIVE: To determine if kindergartens' environmental status can influence children's lead exposure. METHODS: Environmental specimens, such as floor dust, peeled-off paint chip, soil and drinking water, as well as children's hand dust and blood samples, were collected and measured for their lead levels in 19 kindergartens, to analyze the relationship between children's blood lead levels and their environmental lead exposure. RESULTS: Geometric means of lead concentrations in indoor floor dust, peeled-off paint chip, dust fallout, outdoor floor dust, soil and drinking water were 86.5 microg/m(2), 235.5 microg/g, 445.9 microg/g, 172.4 microg/m(2), 70.1 microg/g and 12.5 microg/L, respectively. Lead level on children's hands averaged 3.4 microg at both hands. Blood lead levels in children correlated positively with the lead concentrations of outdoor floor dust and their hand dust, with correlation coefficients of 0.5186 and 0.2206, respectively. Multiple regression analysis showed that hand dust lead level in children entered the regression model with a largest standardized partial regression coefficient of 0.3842 and a coefficient of determination of 0.673 for the full equation with F = 6.52 and P < 0.01. CONCLUSION: Status of environmental health in kindergartens plays an important role in children's lead exposure. It is necessary to offer health education for children and make them wash their hands often and overcome unhealthy behavior of sucking their fingers.

Child Day Care Centers↗
PubMed1999

[Relationship between bone mineral density and blood and urine biochemical indices in women].

OBJECTIVE: To study the relationship between bone mineral density (BMD) and some biochemical indices in their blood and urine of women. METHODS: Fasting urinary calcium (Ca) and creatinine (Cr), ratio of Ca to Cr, urinary hydroxyproline (Hyp), ratio of Hypr to Cr were determined in 163 healthy women, and activity of serum alkaline phosphatase (AKP) were determined in 182 healthy women. BMD at the 1/10 lower end and 1/3 middle-lower site of the radius were measured with single photon absorptiometry for all of them. RESULTS: Serum AKP and ratio of urinary Hyp/Cr increased with age, especially postmenopause, and correlated negatively with BMD. Fasting urinary Ca/Cr ratio also increased with age, especially postmanopause, but not correlated with BMD. CONCLUSION: Serum AKP and fasting urine Hyp/Cr ratio could be used as indicators to reflect bone remodeling and absorption, respectively.

Absorptiometry, Photon↗
PubMed1999

[Effects of lead exposure on their brain-stem auditory evoked potential in children].

OBJECTIVE: To determine if low lead exposure can influence auditory development in children. METHODS: Children were divided into two groups, i.e., low (< 0.483 micromol/L) and high (>or= 0.483 micromol/L) blood lead levels with atomic spectrophotometry (AAS). Latencies and latent intervals between peak waves of their brain-stem auditory evoked potentials (BAEP) in the two groups were measured and compared. RESULTS: There was positive correlation between blood lead levels and BAEP in wave III at right ear, wave V at both right and left ears and latent intervals between peak waves I to V, with correlation coefficients of 0.2991, 0.2748, 0.3248, 0.2064 and 0.2412, respectively. There was significant difference in latencies of wave III at right ear, wave V at both right and left ears and latent intervals between peak waves I to V at both right and left ears and those between waves of III to V at right ear in the low blood lead group. Latencies and latent intervals between peak waves were longer in the high blood level group (with a mean of 0.78 micromol/L and a range of 0.58 to 1.42 micromol/L) than those in the low one (with a mean of 0.30 micromol/L and a range of 0.17 to 0.45 micromol/L). CONCLUSION: Elevated blood lead level could cause prolongation of latencies and latent intervals between peak waves of BAEP and slowdown of the nerve conduction velocity, and so auditory development was influenced.

Child↗
PubMed1999

[Pathogenic gene analysis of Listeria isolated from foods].

In 1996-1997, Listeria in foods from 12 provinces of China were detected by using the national standard examination method GB 4789.30-94 (routine traditional methods). Twenty four strains Listeria monocytogenes and 141 strains Listeria were identified by biochemical procedures and animal toxicity experiment. Polymerase Chain Reaction(PCR) was used to amplify two specific DNA fragments(719 bp and 446 bp) of listeriolysin O and internalin genes with two pairs of primer--Hly1-2 and Inl1-2, respectively. The experiment results showed that 57 strains contained only internalin, 27 strains contained both internalin and listeriolysin O from the pathogenic genes of isolated strains.

Animals↗
PubMed1999

[Preventive effect of vitamin K1 and calcium on osteoporosis in ovariectomized rat].

Ovariectomized female Wistar rats[(170 +/- 15) g] were treated with vitamin K1 or/and calcium for 6 months, in order to study the effect of vitamin K or/and calcium supplementation on the prevention of osteoporosis. Vitamin K1(90 mg/kg) or/and calcium(5 g/kg) were added to a semisynthetic basal diet (VK 50 micrograms/kg, Ca5 g/kg). The findings of the study were as follows: Vitamin K1 treatment led to a significant increase of bone mineral density of the femoral diaphysis and lumbar spine, and bone ash content of the proximal one third of the femur shaft. The results suggested that vitamin K1 could, to some extent, prevent the fast bone loss and the femoral fragility induced by ovariectomy. Regarding the parameters of bone metrology and biomechanics, the effect of vitamin K1 combined with calcium on the prevention of osteoporosis is better than that of vitamin K1 or calcium alone, and the treatments with VK and Ca had better effects on femur than lumbar spine. The present study indicates that for postmenopausal women, as a risk population of osteoporosis, to increase their dietary intake of vitamin K and calcium might be helpful.

Animals↗
PubMed1999

[An analysis of DNA content in 405 cases of human tumor by flow cytometry].

This study was intended to evaluate the relationship between the DNA content of cell cycle and the histology in human tumors. We detected the DNA content in 405 cases of fresh human tumor tissue by means of flow cytometry and observed the histology of tumor with light microscopy. The occurrences of aneuploidy in 22 cases of benign tumor and 383 cases of malignant tumor were 27% and 52% respectively. There were differences in aneuploidy in different histologic types of tumor. The aneuploidy in adenocarcinoma was about 50%, that in sarcoma was more than 37%, and that in squamous carcinoma less than 17%. S > or = 10, G2/m > or = 10 or S > or = 20, G2/m > or = 5 were present in malignant tumors, but were not found in benign tumors. The results suggest that there is obvious difference in the occurrences of aneuploidy in benign and malignant tumors and in different histologic type of tumor(P < 0.05). Benign and malignant tumor may be distinguished when SPF and G2/m reach a higher level (P < 0.01).

Carcinoma, Squamous Cell↗
PubMed1999

[Determination of 2,4-dinitrophenol by solid-phase microextraction coupled to GC/MS].

Solid-phase microextraction coupled GC/MS was investigated for the determination of 2,4-dinitrophenol in aqueous sample. Analytes were extracted by a 85 microns polyacrylate coated fiber. The fiber was then transferred into the injector of GC. Analytes were thermally desorbed and detected by GC/MS. The influences of several parameters on SPME procedure have been studied. The optimization condition was obtained: directly sampling in the water sample with the extraction period was 30 min and the desorption time 3 min at 270 degrees C. Acidification by hydrochloric acid (pH 2) and saturated salt were necessary for the best sensitivity. The precision of SPME is better than that of liquid-liquid extraction. This method is a fast, simple, and pre-concentration-free technique, which is suitable for detecting 2,4-dinitrophenol in water sample.

2,4-Dinitrophenol↗
PubMed1999

[A new algorithm for direct volume rendering of medic image series].

In this paper, a new algorithm based on Voxel Model is proposed. This algorithm combines the advantages of surface rendering and direct volume rendering. In the process of 3D reconstruction, OpenGL graphic standard and hardware accelerator can be used. By doing so, better reconstruction, result and fast speed can be achieved. Also, it is simple to turn this algorithm into programs.

Algorithms↗
PubMed1999

[Preparation of latices with functional group containing N and their application in rapid diagnosis of some diseases].

This article reports the preparation and diagnostic application of a variety of latices. These latices, including temary copolymer diazo latex, azidocarbonyl latex and cell labeling latex are stable, monodisperse, soap-free, and covalently combined with protein in the absence of condensing agent. We have improved diazo polystyrene latex and made ternary copolymer diazo latex for early and rapid diagnosis of some diseases. Immunoassay reagent for the dectection of dengue fever has been prepared by our lab using ternary copolymeric diazo latex and azidocarbonyl latex. The experiment showed virus antigen could be detected in 5 mins by using diazo diagnostic agent. The sensitivity of detecting patient serum sample was 82.25%; no-across reaction was observed in other inserted spread virus antigens and in serum of other feverish patient and normal control. 40 serum samples were dectected by latex agglutination assay using ternary copolymeric diazo latex immunoassay reagent. The results were compared with those of PCR and virus separation methods. The sensitivities of the three methods were 82.25%, 75% and 55% respectively; the combined sensitivity was 92.5%; higher sensitivities could be obtained by the former two methods within 1-13 days after the onset of disease.

Azides↗
PubMed1999

[Construction of thermotolerant ethanol-producing yeast by protoplast fusion].

Protoplast fusion between Saccharomyces cerevisiae A001 and Kluyveromyces Y034 has been studied. A001 is a high alcohol yield yeast and can ferment maltose into ethanol, but can not grow at 45 degrees C. However, Y034 can grow above 45 degrees C but has a lower alcohol yield and can not ferment maltose. We obtained the fusants which were tested in several aspects such as cell morphology, physiological and biochemical feature, isozyme patterns analysis, alcohol fermentation at high temperature(45 degrees C) and so on. The fusant AY023 with the final ethanol concentration of 7.4% has been selected, which is thermotolerant yeast with the highest alcohol yield at 45 degrees C until now.

Cell Fusion↗
PubMed1999

[Expression detection and location analysis of BstNI isoschizomer restriction-modification system gene].

Some genetic markers of E. coli HB101 and JM110 were identified, two bacterial strains were used as recipients respectively to detect the expression of a restriction endonuclease(R) gene and a methylase(M) gene of BstNI isoschizomer restriction-modification system. DNA fragment containing the R-M genes was deleted unilaterally with exoIII and 23 deletion subclones were obtained. According to the Enzyme activity of each subclone, R and M gene were located respectively at the regions of 0.2-->1.4 kb and 1.5-->3.3 kb from cloning site PstI. Analysis showed that the R. M system belongs to type II, two genes are controlled by the different promoters; the recognition sequence of this system is the same as that of DNA-cytosine methyltransferase(Dcm), the latter's methylation function can resist the R enzyme. It was interesting that the recombinant plasmid with an R+ M- genotype appeared to be lethal to dcm+ hosts yet. This indicated that the M gene closely linking to R gene is of critical importance for the existence of the R-M system in process of evolution.

Chromosome Mapping↗
PubMed1999

[The development of an intelligent vision testing instrument].

The paper introduces an intelligent vision testing instrument, which works on automatic method or manual method. The examinee inputs his or her judgement about the direction of the letter "E" with remote control. The system examines and judges the examinee's judgement, and then prints the testing report. The vision testing range is from logarithm vision 3.0 to 5.3. The distance between examinee and optometer can be measured automatically by the system with infrared and ultrasonic testing functions and a good accuracy.

Diagnosis, Computer-Assisted↗
PubMed1999

[Expression of estradiol receptors in mast cells of the upper airway].

OBJECTIVE: To examine the expression of estrogen receptors in mast cells, CD4+, CD8+ and CD68+ cells in human nasal polyps. METHODS: Immunohistochemical and dual immunostaining methods were used with mouse monoclonal antibodies against human estrogen receptors, a range of human immune cell types included CD4+ (helper T-cells), CD8+ (suppressor/cytotoxic T-cells), CD68+ (Macrophages) cells and mast cells. RESULTS: Coincident with the known features of human nasal polyps, all the immune/inflammatory cell types examined were clearly detected with corresponding monoclonal antibodies. The cells positive for estrogen receptor were morphologically similar to the mast cells but distinct from CD4+, CD8+ or CD68+ cells. The cells stained for estrogen receptors by dual immunostaining coincided exactly with cells labeled as mast cells but differed from CD4+, CD8+ or CD68+ cells. CONCLUSION: Estrogen receptors express only in mast cells, but not in CD4+, CD8+ or CD68+ cells in the human upper airway.

Adult↗