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Biomedical subjects

X Fu

Publications and source records attributed to X Fu.

At least 55 records · Page 3Linked to original sources
PubMed2000

Simplified screening for organic acidemia using GC/MS and dried urine filter paper: a study on neonatal mass screening.

A simplified method for organic acidemia screening using GC/MS, the urease/direct method, is now available. To establish a practical screening system for organic acidemias, we studied the usefulness of dried urine filter paper (filter paper urine) and the application of a personal computer-based system of automated metabolic profiling and interpretation (automated system) that we earlier developed. In a comparison of filter paper urine with liquid urine, creatinine levels ranging from 4.6 to 122.5 mg/dl, showed an excellent correlation (r=0.9554), when the volumes of blotted urine and distilled water soaked were the same. Recovery of all 17 compounds except for citrate was similar between liquid and filter paper urine. CV values of 22 compounds tested ranged from 5.5 to 22.4% in the liquid urine, and from 7.7 to 29.8% in the filter paper urine. The CV values in stable isotope dilution analysis were much smaller in all nine compounds tested. As to the stability of compounds, the percentage changes to values at day 0 were within about +/-25% on day 28. We compiled GC/MS data, including methylene unit values, quantifying and confirming ions of 163 different organic acids and others, to use the automated system. We analyzed specimens from 55 patients with 17 different metabolic disorders. In 54 of the 55 specimens, the correct diagnosis was successfully indicated. Neonatal mass screening for organic acidemias warrants ongoing attention using this simplified method and filter paper urine.

Acidosis↗
PubMed2000

Equilibrium modeling of 5-HT(2A) receptors with [18F]deuteroaltanserin and PET: feasibility of a constant infusion paradigm.

[(18)F]Altanserin has emerged as a promising positron emission tomography (PET) ligand for serotonin-2A (5-HT(2A)) receptors. The deuterium substitution of both of the 2'-hydrogens of altanserin ([(18)F]deuteroaltanserin) yields a metabolically more stable radiotracer with higher ratios of parent tracer to radiometabolites and increased specific brain uptake than [(18)F]altanserin. The slower metabolism of the deuterated analog might preclude the possibility of achieving stable plasma and brain activities with a bolus plus constant infusion within a reasonable time frame for an (18)F-labeled tracer (T(1/2) 110 min). Thus, the purpose of this study was to test the feasibility in human subjects of a constant infusion paradigm for equilibrium modeling of [(18)F]deuteroaltanserin with PET. Seven healthy male subjects were injected with [(18)F]deuteroaltanserin as a bolus plus constant infusion lasting 10 h postinjection. PET acquisitions and venous blood sampling were performed throughout the infusion period. Linear regression analysis revealed that time-activity curves for both specific brain uptake and plasma [(18)F]deuteroaltanserin concentration stabilized after about 5 h. This permitted equilibrium modeling and estimation of V(')(3) (ratio of specific uptake to total plasma parent concentration) and the binding potential V(3) (ratio of specific uptake to free plasma parent concentration). Cortical/cerebellar ratios were increased by 26% relative to those we previously observed with [(18)F]altanserin using similar methodology in a somewhat older subject sample. These results demonstrate feasibility of equilibrium imaging with [(18)F]deuteroaltanserin and suggest that it may be superior to [(18)F]altanserin as a PET radioligand.

Adolescent↗
PubMed2000

Linear transgene constructs lacking vector backbone sequences generate low-copy-number transgenic plants with simple integration patterns.

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). This is undesirable, as vector backbone sequences often have negative effects on transgene or endogenous gene expression, and can promote transgene rearrangements. We, therefore, bombarded rice tissue with two constructs: a plasmid containing the bar gene, and a linear DNA fragment isolated from the same plasmid, corresponding to the minimal bar gene expression cassette (promoter, open reading frame and terminator). We recovered phosphinothricin-resistant plants from both experiments, showing that the selectable marker was efficiently expressed. Transformation with such constructs resulted in predominantly 'simple' integration events (one or two bands on Southern blots), producing low-copy-number transgenic plants with a low frequency of transgene rearrangements. Conversely, transformation with supercoiled or linearized whole plasmids generated plants with 'complex' integration patterns, that is, higher copy numbers and frequent transgene rearrangements. We monitored transgenic lines through to the R4 generation and observed no silencing in plants carrying minimal constructs. We also carried out experiments in which rice tissue was simultaneously bombarded with minimal linear hpt and gusA cassettes. We observed robust GUS activity in hygromycin-resistant plants, confirming co-expression of the selectable and nonselectable markers. Furthermore, the efficiency of cotransformation using minimal constructs was the same as that using supercoiled plasmid cointegrate vectors.

Acetyltransferases↗
PubMed2000

Prostaglandin F2alpha-induced Ca++ oscillations in human myometrial cells and the role of RU 486.

OBJECTIVE: We sought to examine the change of cytosolic calcium concentration caused by prostaglandin F(2)(alpha) and RU 486 in cultured human myometrial cells. STUDY DESIGN: Human myometrial cells obtained from 16 nonpregnant women were loaded with fura 2, and the intracellular cytosolic calcium concentrations were measured by the use of wavelength spectrophotofluorometry. RESULTS: Application of prostaglandin F(2)(alpha) (2.8 micromol/L) caused an initial rapid rise in cytosolic calcium concentration followed by sustained cytosolic calcium oscillations at an average frequency of 0.43 +/- 0.04 min(-1) and an amplitude in the range of 296.82 +/- 27. 16 nmol/L. The oscillatory activity was not affected by increasing the concentration of prostaglandin F(2)(alpha) but varied by changing the concentration of extracellular cytosolic calcium concentration. The cytosolic calcium oscillations were suppressed by caffeine, 2,5-di-tert-butylhydroquinone, and lanthanum but not affected by ryanodine. Verapamil decreased the amplitude but not the frequency of oscillations. The progesterone antagonist RU 486 at a concentration of 10(-8) to 10(-5) mol/L had no significant effect on the basal intracellular cytosolic calcium. However, RU 486 (10(-5) mol/L) significantly increased the frequency but not the amplitude of intracellular cytosolic calcium oscillations induced by prostaglandin F(2)(alpha). CONCLUSION: The results indicate that prostaglandin F(2)(alpha)-stimulated cytosolic calcium oscillations are mediated by an increase in both cytosolic calcium release from inositol 1,4,5-trisphosphate-sensitive cytosolic calcium stores and a cytosolic calcium influx from the extracellular space. Moreover, RU 486 seems to directly regulate prostaglandin F(2)(alpha)-induced intracellular cytosolic calcium in human myometrial cells.

Adult↗
PubMed2000

Color Doppler flow imaging of the facial artery and vein.

The purpose of this study was to provide some guidelines with respect to the location of the facial vessels, display the potential inverted blood flow of the facial artery, and reemphasize the value of color Doppler ultrasound studies in flap planning. An anatomic study of the facial artery and vein was done using color Doppler ultrasonography in 12 adults. The artery and the vein were located together at the lower border of the mandible. Around the oral commissure and under the nasal ala, they were located apart from each other with variable distances. This divergence of the facial vein from the artery is important information in the planning of axial pattern flaps. Furthermore, the reverse flow was observed in 12 patients after the blood flow of the facial artery was stopped by applying pressure manually at the lower border of the mandible. Observation of the reversed flow confirms the possibility of safe elevation of a retrograde flow-arterialized flap based on the distal portion of the facial artery.

Adolescent↗
PubMed2000

Development of a chromosome-plasmid balanced lethal system for Lactobacillus acidophilus with thyA gene as selective marker.

A chromosome-plasmid balanced lethal gene delivery system for Lactobacillus acidophilus based on the thyA gene was developed. The selected L. acidophilus DOM La strain carries a mutated thyA gene and has an obligate requirement for thymidine. This strain can be used as a host for the constructed shuttle vector pFXL03, lacking antibiotic-resistant markers but having the wild-type thyA gene from L. casei which complements the thyA chromosomal mutation. The vector also contains the replicon region from plasmid pUC19 and that of the Lactococcus plasmid pWV01, which allows the transfer between Escherichia coli, L. casei and L. acidophilus. Eight unique restriction sites (i.e., PstI, HindIII, SphI, SalI, AccI, XbaI, KpnI and SacI) are available for cloning. After 40-time transfers in modified MRS medium, no plasmid loss was observed. The vector pFXL03 is potentially useful as a food-grade vaccine delivery system for L. acidophilus.

Drug Delivery Systems↗
PubMed2000

Membrane redistribution of the Escherichia coli MinD protein induced by MinE.

Escherichia coli cells contain potential division sites at midcell and adjacent to the cell poles. Selection of the correct division site at midcell is controlled by three proteins: MinC, MinD, and MinE. It has previously been shown (D. Raskin and P. de Boer, Cell 91:685-694, 1997) that MinE-Gfp localizes to the midcell site in an MinD-dependent manner. We use here Gfp-MinD to show that MinD associates with the membrane around the entire periphery of the cell in the absence of the other Min proteins and that MinE is capable of altering the membrane distribution pattern of Gfp-MinD. Studies with the isolated N-terminal and C-terminal MinE domains indicated different roles for the two MinE domains in the redistribution of membrane-associated MinD.

Adenosine Triphosphatases↗
PubMed2000

Agricultural work-related injuries among farmers in Hubei, People's Republic of China.

OBJECTIVES: This population-based study evaluated patterns of and risk factors for, agricultural injuries among farmers in the People's Republic of China. METHODS: A multistage sample of 1500 Chinese farmers was selected from 14 villages. Face-to-face interviews with 1358 farmers were conducted between July 1997 and September 1997 (response rate = 91%). Agricultural work-related injuries that occurred in the previous 24 months and the associated factors were evaluated. RESULTS: A total of 33% of the farmers reported at least 1 work-related injury in the 24 months before the survey. Major external causes of the injuries were hand tools (50%), falls (26%), and heavy falling objects (10%). The statistically significant risk factors for injury were low family income, 1 to 6 school years of education, self-reported pesticide exposure, tension in relationships with neighbors, and stress in life. The most notable result was the relation between self-reported pesticide exposure and injury, with farmers with greater pesticide exposure at significantly greater risk for injury. CONCLUSIONS: The results of this study indicated that injuries occurring among Chinese farmers may have unique patterns and potential risk factors.

Accidents, Occupational↗
PubMed2000

Oxytocin-induced oscillations of cytoplasmic Ca2+ in human myometrial cells.

BACKGROUND: To investigate the mechanisms of oxytocin (OT) induced oscillations of the cytoplasmic Ca2+ concentration ([Ca2+]i) in cultured human myometrial cells. METHODS: [Ca2+]i was measured in individual myometrial cells by dual wavelength spectrophotofluorometry using the fluorescent indicator fura-2. Myometrium was obtained at abdominal hysterectomy (n=8) and during cesarean section (n=7). RESULTS: OT (10-300 nM) typically induced [Ca2+]i oscillations with frequencies in the 0.6-0.8/min range. There were no obvious differences in the responses of cells taken from non-pregnant and term pregnant women. The frequency and amplitude of the oscillations were not significantly affected by OT concentrations up to 300 nM. The amplitude of the oscillations decreased in the presence of the voltage-dependent Ca2+ channel antagonist verapamil and gradually disappeared in Ca2+-free medium. The oscillations were further blocked by the inorganic Ca2+ antagonist La3+ and by the intracellular Ca2+-ATPase inhibitor 2.5-di-tert-butylhydroquinone (DTBHQ). Caffeine inhibited the OT-induced oscillations in a concentration-dependent manner. DTBHQ and high concentrations of OT made [Ca2+]i remarkably sensitive to changes in the external Ca2+ concentration. CONCLUSIONS: The results indicate that OT-induced [Ca2+]i oscillations in human myometrial cells are due to inositol 1,4,5-trisphosphate-mediated release of intracellular Ca2+ combined with capacitative as well as voltage-dependent influx of the ion.

Calcium Signaling↗
PubMed2000

[A system of microcomputer analysis for biological oxygen consumption and its application].

This paper introduces a microcomputer system of data analysis and methods of measuring oxygen consumption for biological materials. The system overcame some disadvantages of operating inconvenience and difficulties of collective and analytic data by traditional means. The system possesses functions of automatic enactment, collection, save/take and analysis for many experimental data. It can be used to measure oxygen consumption of tissues, cells and mitochondria.

Animals↗
PubMed2000

Recombinant bovine basic fibroblast growth factor accelerates wound healing in patients with burns, donor sites and chronic dermal ulcers.

OBJECTIVE: To evaluate the effect of recombinant bovine basic fibroblast growth factor (rbFGF) on accelerating healing of burn wounds, donor sites and chronic dermal ulcers in multicenters. METHODS: One thousand and twenty-four patients with burns, donor sites and chronic dermal ulcers were recruited for this prospective and multicenter clinical trial and another 641 patients with the similar wounds were used as controls. All patients were divided into three groups: burn group, donor site group, and chronic dermal ulcer group. In the burn group, 654 patients with superficial second-degree burns(superficial II degree) or deep second-degree burns(deep II degree) were treated topically with either recombinant bovine basic fibroblast growth factor (rbFGF plus vehicle, rbFGF 150 AU/cm2/day, 330 patients) or placebo (vehicle without rbFGF, 324 patients). In the donor site group, 509 patients were treated with rbFGF and 317 patients with placebo in a similar way as described elsewhere. In the chronic dermal ulcer group, 185 patients were treated with rbFGF and the controls were themselves. Photography, histological evaluation and clinical examination were used to evaluate the results of wound healing. RESULTS: All of superficial second-degree burns, deep second-degree burns and the donor sites treated with recombinant bovine basic fibroblast growth factor had an accelerated rate of granulation tissue formation and epidermal regeneration as compared with that in the controls. Superficial second-degree burns and deep second-degree burns treated with recombinant bovine basic fibroblast growth factor healed in 9.89 +/- 2.45 and 17.04 +/- 4.56 days, respectively, whereas the average healing time in those receiving placebo was 12.35 +/- 2.74 and 21.21 +/- 4.88 days. The donor sites treated with rbFGF or placebo healed in 10.68 +/- 4.55 and 14.74 +/- 6.46 days, respectively. All chronic dermal ulcers except 12 patients treated with rbFGF healed within 6 weeks. Histological evaluation of punch-biopsy specimens from the burn wounds, donor sites and chronic dermal ulcers seven days after treatment supported the impression of accelerated wound healing after rbFGF treatment. CONCLUSIONS: rbFGF is effective in shortening the wound healing time and improving the wound healing quality. Accelerating wound healing is of clinical benefit in reducing the length of hospitalization, costs and emotional burden of the patient.

Adolescent↗
PubMed2000

[Clinical study on treatment of advanced non-small cell lung cancer with Chinese herbal medicine combined with synchronous radio- and chemotherapy].

OBJECTIVE: To explore the effect of applying Chinese herbal medicine according to Syndrome Differentiation of TCM combined with synchronous radio- and chemotherapy (combination therapy) in treating advanced non-small cell lung cancer (NSCLC). METHODS: The 56 patients in the group A were treated with combination therapy, and the 44 patients in the group B treated with synchronous radio- and chemotherapy, while the 34 patients in the group C treated with non-synchronous radio- and chemotherapy. The efficacy of treatment in the three groups were observed and compared. RESULTS: The immediate effective rate in the A, B, C groups was 87.5%, 84.1% and 55.9% respectively, that in the group A and B was better than that in the group C (P < 0.01). The median survival time in the three groups was 16.4, 11.8 and 10.6 months respectively. The 2-year and 3-year survival rate in the group A were markedly higher than those in the group B (P < 0.05), moreover, the clinical symptoms, Karnovsky scoring and immune function were obviously improved in the group A (P < 0.05, P < 0.01). CONCLUSION: Effect of the combination therapy is superior to that of synchronous radio- and chemotherapy alone in improving immune function, elevating quality of life and prolongating survival time of patients with NSCLC.

Adenocarcinoma↗
PubMed2000

[The expressions of transcription factor c-fos mRNA and its protein in the burn wound of rats].

OBJECTIVE: To investigate the rule of the expression in different time points of wound tissue transcription factor c-fos mRNA and its protein after burn, so as to explore the role of c-fos in the initiation of burn wound injury and repairing. METHODS: Male Wistar rats were inflicted with partial thickness scalding of 30% TBSA on the back. In situ hybridization and immunohistochemical methods were used to evaluate the characteristics and pattern of the changes in the expressions of the c-fos mRNA and its protein in normal skin and in the wounded skin at 3 h, 6 h, 1 d, 3 d, 7 d and 14 d postburn, respectively. RESULTS: It was found by light microscopy (LM) that c-fos mRNA and its protein could be found expressed in normal skin and obviously increasingly expressed in wounded skin. The expression of fos protein reached peak level at 3 postburn hour (PBH) and that of its mRNA at 6 PBH. CONCLUSION: The expression of c-fos mRNA and its protein could be induced during burn injury. But the postburn increase in the expression of its gene appeared later than that of its protein, suggesting that the early-appeared fos protein acted through its post-translational modification of preexisting fos molecule.

Animals↗
PubMed2000

[The significance and characteristics of the gene expressions of c-fos and c-jun in hypertrophic scar and chronic ulcer tissues].

OBJECTIVE: To explore the characteristics and regularity of the expression of c-fos and c-jun genes in hypertrophic scar and chronic ulcer tissues and their relationship to different tissue restoration. METHODS: Tissue samples of hypertrophic scars were harvested from 16 cases of patients after burns and chronic cutaneous ulcers during operation together with the normal skin (n = 5) of the same patients as control. ABC method was employed to detect the gene expression of both c- fos and c-jun in above samples. RESULTS: The positive expression of c-fos and c-jun gene was found in epithelial basal cells and some subcutaneous fibroblasts in normal skin. But the expression of c-jun was weaker than that of c-fos in above tissues. A strong positive expression of c-fos and c-jun genes was found mainly in fibroblasts in the hypertrophic scar. But the combined expression of both tumor genes was most often found in the capillary endothelium, some inflammatory cells and the cytoplasm of fibroblasts in ulcer tissue. CONCLUSION: The results indicated that the amount and location of the expression of c-fos and c-jun genes were different in the three kinds of tissues, suggesting that these two tumor genes may play important roles in wound healing modulation.

Adult↗
PubMed2000

[Preparation of galactosyl-insulin with double saccharide density and a study of its hepatic targeting property].

This study was intended to improve the technical procedure so as to increase the saccharide density of galactosyl-recombinant insulin and elevate its liver targeting property. Using a branched compound 3,5-dihydroxy benzoic acid as the base of a conjugating bridge, the authors prepared a new double galactosyl-recombinant insulin, whose saccharide density being two times as high as that of galactosyl-recombinant insulin. The double gal-insulin conjugate, gal-insulin conjugate and original insulin were labeled with 131I, and then the three kinds of 131I labeled compounds were tested in rabbit whole body imaging to measure their properties of liver targeting. The peak values of rabbit liver concentration for double gal-insulin, gal-insulin and original insulin were 59.5%, 43.8% and 21.5%, respectively. These results demonstrate that for elevating the liver targeting property of galactosyl-recombinant compounds, a branched agent like 3,5-dihydroxyl benzoic acid can be adopted as an effective medium.

Animals↗
PubMed2000

[Content analysis on gardenoside in grown and ungrown fruits of Gardenia from different habitats].

This paper reported content analysis on gardenoside in grown fruits of Gardenia from different habitats and ungrown fruits of Gardenia jasminoides and G. jasminoides f. longicarpa. The results were as follows: (1) The content of gardenoside in G. jasminoides from indigenous region of Jiangxi was higher than other habitats; (2) The content of gardenoside in G. jasminoides f. longicarpa was the highest; (3) The content of gardenoside in fruits of growth period of G. jasminoides and G. jasminoides f. longicarpa had two peak stages.

Chromatography, High Pressure Liquid↗
PubMed2000

[Raman and infrared spectroscopic investigation of SO4(2-)/TiO2 solid acids].

The structure, crystal phase transition and surface acid centers of SO4(2-)/TiO2 solid acids calcined at different temperatures were studied by IR and Raman spectroscopy. The results showed that SO4(2-) is combined with metal ions of TiO2 in a chelating bidentate mode. When the calcination temperature is below 500 degrees C, the samples possess stable structure with anatase as the main crystal phase, and there are two types of acid sites (Lewis and Bronsted acid) on the samples, the amount of B acid is about twice as that of L acid. When the temperature is above 500 degrees C, surface SO4(2-) desorb gradually with increasing calcination temperature, leading to crystal phase transition from anatase to rutile and the surface B acid sites fade away.

Acids↗