Search PubMed⌕ Search

Biomedical subjects

F Sun

Publications and source records attributed to F Sun.

At least 91 records · Page 5Linked to original sources

Increase of lipid hydroperoxides in the rat liver and kidney after administering ferric nitrilotriacetate.

Two hours after an intraperitoneal injection of ferric nitrilotriacetate to rats at a dose of 15 mg of Fe/kg of body weight, the level of lipid hydroperoxides, which was determined by a specific method involving chemical conversion into 1-naphthyldiphenylphosphine oxide and HPLC, had increased significantly in the liver (from 190.1 +/- 58.8 of the control to 467.1 +/- 175.8 pmol/mg of protein) and kidney (from 181.8 +/- 52.3 of the control to 405.9 +/- 22.7 pmol/mg of protein). These results demonstrate that oxidative stress was transiently increased by an iron overload in these tissues.

Animals↗

Application of acupuncture and moxibustion for keeping shape.

On the basis of TCM diferentiation, the authors have treated 359 adult female cases of non-obesity with undesirable body shape by combined application of body acupuncture and moxibustion and auricular acupuncture, and achieved quite good remoulding and orthopedic results, suggesting that acupuncture and moxibustion can very effectively regulate the somatotypic indexes of body weight, circumference of the chest, loin, hip and thigh, the ratio of the loin to hip, sebum thickness, obesity degree, body mass index and body fat percentage of the cases in the overweight group and orthopedic groups 1, 2. It is therefore concluded that acupuncture and moxibustion is a good therapy for obtaining a graceful body shape.

Acupuncture Therapy↗

[Emergency measures on drinking water sanitation for mitigation of flood and waterlogging disasters].

This article reports the emergency measures for mitigation during flood and waterlogging disasters to ensure drinking water sanitation and to prevent infectious disease outbreaks. Five preparatory and preventive measures for flood and waterlogging disasters include the construction of dual-purpose water supply installation for ordinary and disaster use, the storage of qualified technicians and materials (or their inventories), and the formulation of predetermination programme for disaster relief, ect.

China↗

[Magnetic resonant imaging diagnosis and differential diagnosis in choroidal melanoma].

OBJECTIVE: To evaluate the diagnostic value of magnetic resonant imaging (MRI) for choroidal melanoma. METHODS: 12 cases of choroidal melanoma were diagnosed by means of B-ultra-sonography, computed tomography (CT), MRI and pathology. RESULTS: The MRI features of melanoma were: T(1)WI shows high signal, and T(2)WI shows low signal. CONCLUSION: Besides B-ultra-sonography and CT, MRI is also valuable in the diagnosis and differential diagnosis of choroidal melanoma.

Adult↗

[The manifestations of 496 cases with thyroid-related immune orbitopathy and normal thyroid function].

OBJECTIVE: To observe the clinical manifestations of thyroid-related immune orbitopathy (TRIO) with normal thyroid function. METHODS: 496 cases with TRIO were collected from 1973 to 1994 and their clinical manifestations were analyzed. RESULTS: The clinical manifestations showed that males are more than females. The disease occurred in middle aged persons with unilateral exophthalmos as the primary early manifestation. Most of the cases had the signs of eyelids and extraocular muscle involvement. CONCLUSIONS: The thyroid-related immune orbitopathy with normal thyroid function can be named thyroid-related immune orbitopathy-II. The clinical characteristics of this disease are unilateral, of signs of eyelids, exophthalmos and enlargement of eye muscles. The pseudo-tumors of the orbit are mainly considered for differential diagnosis.

Adolescent↗

[A study of cytokines in pathogenesis of thyroid-related immune orbitopathy].

OBJECTIVE: To explore the pathogenesis of thyroid-related immune orbitopathy (TRIO). METHODS: Human orbital fibroblasts were cultured in vitro and immunohistochemical techniques were used to study cytokines that induce effect on HLA-II antigen expression of orbital fibroblasts. RESULTS: It is shown that interferon-gamma (IFN-gamma), interleukin-1 (IL-1) and tumor necrosis factor (TNF) could induce the expression of orbital fibroblast HLA-II antigens. The induced effect of IFN-gamma is of good linear correlations with time and concentration. CONCLUSION: HLA-II antigen expression can be induced by IFN-gamma, IL-1 and TNF. In the course of immune reaction and pathogenesis of TRIO, cytokines play important roles.

Cytokines↗

Sequential sib-pair and association studies to detect genes in quantitative traits.

We applied sib-pair and association methods to a GAW data set of nuclear families with quantitative traits. Our approaches included 1) preliminary statistical studies including correlations and linear regressions, 2) sib-pair methods, and 3) association studies. We used a single data set to screen for linkage and association and, subsequently, additional data sets to confirm the preliminary results. Using this sequential approach, sib-pair analysis provided evidence for the genes influencing Q1, Q2, and Q4. We correctly predicted MG1 for Q1, MG2 for Q2, and MG4 for Q4. We did not find any false positives using this approach. Association studies identified chromosomes 8 and 9 to be associated with Q4; however these are assumed to be false positives as no associations were modeled into the data.

Analysis of Variance↗

The method of sib-pair linkage analysis in context of case-control design.

We used sib-pair linkage analysis as part of an epidemiologic approach to solving Problem 2 of the GAW10 data set of nuclear families. We recoded the quantitative trait Q1 into a dichotomous trait using Q1 > or = 40 as the cut-point. In a case-control design of sib-pair analysis, the affected siblings of the proband were the case subjects and the unaffected siblings were the control subjects. Case and control subjects were compared with respect to the number of alleles at one or more loci (0, 1, 2) that were identical-by-descent (IBD) with those of the proband. Odds ratios (ORs) and 95% confidence intervals (95% CI) were then computed with subjects sharing no alleles (share-0) serving as the reference group. Significantly high ORs were taken as indication of linkage between a marker locus and a suspected disease-susceptibility locus. The case-control sib-pair analysis identified marker D5G15 as associated with disease susceptibility (OR of sharing two alleles [share-2] = 7.7 [95% CI 2.5-23.9]). Our results were consistent with the results from Kruglyak and Lander's method of complete multipoint sib-pair analysis for linkage. For the marker (D5G15) identified through sib-pair analysis, we examined the effects of other covariates and evaluated gene-environment interaction using conditional logistic regression.

Case-Control Studies↗

Recruitment of individually (all-or-none) responding cells, rather than amplitude enhancement, is the single-cell mechanism subserving the dose-responsive activation of intracellular calcium second messenger signaling by the human luteinizing-hormone receptor.

We have investigated at the single-cell level how the human LH receptor mediates a dose-responsive increase in intracellular free calcium-ion concentrations ([Ca2+]i). In human embryonic kidney cells (293 cells) stably transfected with the full-length human LH receptor cDNA. Intact dimeric LH, but not LH beta- or alpha-subunits, evoked specific [Ca2+]i signals. High-resolution fluorescence (fura-2) video-microscopy demonstrated cell-to-cell variability in [Ca2+]i signaling responses in individual cells, viz., an all-or-none spike (9%), spike-and-plateau (25%), or plateau (52%) types of temporal signal. Oscillatory [Ca2+]i responses were observed in 12-14% of LH-stimulated cells unrelated to LH concentration. The LH dose-response originated by higher concentrations of LH recruiting more individually responding cells (rather than altering [Ca2+]i signal amplitude), and eliciting a [Ca2+]i rise more rapidly, i.e., at reduced latency. Cobalt did not abolish the LH-stimulated [Ca2+]i spike-and-plateau response, but decreased the percentage of cells with a plateau pattern. Quench experiments demonstrated influx of Mn2+ following the [Ca2+]i spike, thus directly documenting divalent cation inflow during the plateau phase. Adenylyl-cyclase activation with forskolin or treatment with a cAMP analog failed to elicit the biphasic [Ca2+]i response, and pertussis toxin (PTX) did not alter LH-stimulated [Ca2+]i signaling. However, overnight preincubation with LH reduced the percentage of [Ca2+]i-responding cells following re-exposure to LH to 5.7% (vs 72% in control), suggesting LH-induced desensitization of the LH-receptor directed [Ca2+]i signal. In summary, the present studies of human LH receptor signal transduction at the single-cell level show that increasing concentrations of LH achieve a dose-dependent intracellular Ca2+ signaling response by recruiting an increasing number of [Ca2+]i-responding cells, while concomitantly decreasing the temporal latency of the biphasic [Ca2+]i signal without altering the amplitude of its spike phase. Prolonged exposure to LH appears to desensitize the LH receptor-driven [Ca2+]i signal.

Adenylate Cyclase Toxin↗

Expression of functional GABAA receptors in transfected L929 cells isolated by immunomagnetic bead separation.

Transient cotransfection of fibroblasts, with plasmids encoding individual GABAA receptor (GABAAR) subunits, has provided a model to characterize the pharmacological and kinetic properties of receptor subtype combinations. However, identifying transfected cells for electrophysiological recording is often difficult due to low transfection efficiencies. Selection of transfected cells has required cotransfection with a marker gene and fluorescence microscopic localization prior to recording. To circumvent these problems, two GABAAR subtypes combinations in transfected L929 cells were isolated with a novel biomagnetic separation system. Cell selection was accomplished by cotransfection with a plasmid (pHook-1) encoding a single-stranded cell surface antibody (sFv), which bound to ferromagnetic beads, coated with an antigen (phOx). Bead-covered cells were then magnetically separated from non-transfected cells. Bead-selected cells cotransfected with alpha 6, beta 3 and gamma 2L subtypes, expressed GABAAR currents in 95% (41/43) of cells recorded. Cells cotransfected with alpha 5, beta 3 and gamma 2L subtypes had an EC50 for GABA of 5.4 microM and a Hill slope of 1.4. Membrane patches from cells expressing the alpha 5 beta 3 gamma 2L isoform demonstrated single channel currents with a main conductance state of 23 pS. Magnetic bead immunoselection provides a purified population of transfected cells well suited for whole cell and single channel recording.

Animals↗

Pooling strategies for establishing physical genome maps using FISH.

Often, in biological studies, it is necessary to identify an organism's chromosomes. In some organisms the individual chromosomes can be identified by staining procedures while many other species have a very large number of chromosomes, often of similar size, which defy identification by traditional staining methods. We have devised strategies, based on fluorescent in situ hybridization (FISH), which allow the assignment of a preset number of probes to each chromosome without prior chromosome identification. By hybridizing mixtures of probes labeled with different colored fluorescent molecules, the chromosomal origin of each probe can be determined.

Animals↗

Common genomic variation in the APOC3 promoter associated with variation in plasma lipoproteins.

We hypothesized that common genomic variation that affected the expression and/or function of the products of the APOC3, APOE, FABP2, and PON1 genes would be associated with variation in biochemical phenotypes in a previously unstudied human sample. We determined genotypes of functional genomic variants of APOC3, APOE, FABP2, and PON1 in 509 adult aboriginal Canadians from an isolated community in Northern Ontario. We tested for genotype associations with plasma lipoprotein traits. We found that (1) common variation at nucleotide -455 of the APOC3 promoter was associated with variation in plasma triglycerides (P = .006) and (2) common variation of APOE determining plasma isoforms of apo E was associated with variation in plasma apo B (P = .009). Analysis of subjects classed by APOC3 markers showed that homozygosity for presence of a C at nucleotide -455 and a T at nucleotide -482 was associated with significantly increased plasma triglycerides in both men and women. Furthermore, this allele was approximately twice as frequent in subjects within the highest quartile of plasma triglycerides as in subjects within the lowest quartile. Since the DNA variation detected by the APOC3 markers affects in vitro expression of the gene product, it is possible that the marker itself caused the associations. However, the associations could also have resulted from linkage disequilibrium with other functional variants in APOC3 or the closely linked APOA1 and/or APOA4 genes.

Adolescent↗

Common genomic variants associated with variation in plasma lipoproteins in young aboriginal Canadians.

We hypothesized that common genomic variants would be associated with variation in lipoprotein phenotypes in young subjects. We determined genotypes of FABP2, PON, APOC3, and APOE in 188 aboriginal Canadians, aged 9 to 17 years. We found that 13 of 32 possible genotype-phenotype associations were significant: (1) the FABP2 codon 54 genotype was associated with variation in plasma triglycerides (P = .045); (2) the PON codon 192 genotype was associated with variation in plasma total and LDL cholesterol and apoB (P = .0099, P = .0088, and P = .016, respectively); (3) the APOC3 insulin-response-element genotype was associated with variation in plasma triglycerides, HDL cholesterol, apoA-I, the total cholesterol to HDL cholesterol ratio, and the apoB to apoA-I ratio (P = .0014, P = .0069, P = .045, P = .0021, and P = .0081, respectively); and (4) the APOE restriction isotype was associated with variation in plasma LDL cholesterol, apoB, the total cholesterol to HDL cholesterol ratio, and the apoB to apoA-I ratio (P = .025, P = .034, P = .045, and P = .047, respectively). The average young age and relative absence of age-dependent secondary environmental factors could have eased the identification of small genetic effects on lipoprotein phenotypes in this study sample.

Adolescent↗

Angiotensinogen gene variation associated with variation in blood pressure in aboriginal Canadians.

We measured blood pressure and related clinical phenotypes in 497 adult native Canadians from an isolated community in Northern Ontario. We analyzed their DNA for genotypes of angiotensinogen. We found that the frequency of the T235 variant of the angiotensinogen gene was 0.89 in this sample. This variant was associated with a significantly increased systolic pressure but not diastolic pressure. We also found that sex and body mass were each highly significantly associated with variation in both systolic and diastolic pressures. We found a significant association between age and variation in systolic pressure but not diastolic pressure. We also found a highly significant association between plasma apolipoprotein B concentration and variation in diastolic pressure but not systolic pressure. The high frequency of the angiotensinogen T235 variant suggests that subjects in this young, essentially normotensive population might be predisposed to hypertension, which may become more apparent in the presence of secondary factors.

Adult↗

[Effect of frostbite under hypoxia on microcirculatory perfusion in rats].

Changes of microcirculatory perfusion in rats following cold injury of right hind leg under hypoxia were investigated. Male Wistar rats weighing 200 +/- 20 g were randomly divided into three groups: frostbite at normoxia (FN) group; frostbite during acute hypoxia (4 h at 6000 m simulated altitude, FAH) group and frostbite during hypoxia after acclimation (exposure to hypoxia at 6000 m, 4 h daily for 4 weeks, FHAC) group. The results showed that the microcirculatory perfusion of both hind legs decreased markedly in FN after cold injury. It suggests that the frostbite damage can affect microcirculatory perfusion of another leg besides the region of frostbite. The fall of microcirculatory perfusion before freezing in FAH group indicated that there was a compensatory blood redistribution during acute hypoxia. The changes of microcirculatory perfusion in FAH group post-freezing indicated that acute hypoxia can aggravate the frostbite damage. The microcirculatory perfusion of FHAC group pre-freezing was significantly lower than that of FN and FAH group, and after freezing the perfusion of frostbitten leg in FHAC group was significantly lower than that in FN group, suggesting that hypoxia acclimation may cause disturbance of microcirculation and worsen the frostbite damage at high altitude.

Acclimatization↗

[The properties of protease from Bacillus sphaericus C3-41].

The production and properties of protease from Bacillus sphaericus strain C3-41 were reported in this paper. It was found out that the secrete of extracellular protease began at the exponential phase, reached a maximum at the early phase of sporangium and then decrease rapidly. The production conditions of the protease have been studied. The protease preparation was purified by salting out with ammonium sulfate and by chromatography fractionating on Sephadex G-100. The purified enzyme have a specific activity of 6741.5 U/mg protein and a molecular weight of 42,000. The optimal activities of the protease were around pH11.0 and at 4 degrees C respectively. The enzyme was stable at pH5.0-12.0. The proteolytic activity was inhibited by phenylmethylsulphony fluoride (PMSF) and EDTA, but not by IAA, SA and DTT. The activity was inhibited in the presence of Al3+, Hg2+, Fe3+, Cu2+ and Fe2+. The enzyme was sensitive to higher temperature, but was quite stable in the presence of Ca2+.

Bacillus↗

[Determination of inosine in oral tonic by high performance capillary electrophoresis].

This paper describes a high performance capillary electrophoresis method for the assay of inosine in oral tonic. The method employed a boric acid-borate buffer solution with SDS and UV detection at 254 nm. The capillary was 47 cm x 75 microm i.d.. Calibration curve shows good linearity. The recovery of inosine ranged from 95.0%-99.8% with a coefficient of variation (CV) of 2.4% (n=4). This method is simple, rapid and reliable.

Administration, Oral↗