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Biomedical subjects

Q Qi

Publications and source records attributed to Q Qi.

At least 37 records · Page 2Linked to original sources
PubMed1999

Intermittent and continuous administration of the bisphosphonate ibandronate in ovariohysterectomized beagle dogs: effects on bone morphometry and mineral properties.

Bisphosphonates have emerged as a valuable treatment for postmenopausal osteoporosis. Bisphosphonate treatment is usually accompanied by a 3-6% gain in bone mineral density (BMD) during the first year of treatment and by a decrease in bone turnover. Despite low bone turnover, BMD continues to increase slowly beyond the first year of treatment. There is evidence that bisphosphonates not only increase bone volume but also enhance secondary mineralization. The present study was conducted to address this issue and to compare the effects of continuous and intermittent bisphosphonate therapy on static and dynamic parameters of bone structure, formation, and resorption and on mineral properties of bone. Sixty dogs were ovariohysterectomized (OHX) and 10 animals were sham-operated (Sham). Four months after surgery, OHX dogs were divided in six groups (n = 10 each). They received for 1 year ibandronate daily (5 out of 7 days) at a dose of 0, 0.8, 1.2, 4.1, and 14 microg/kg/day or intermittently (65 microg/kg/day, 2 weeks on, 11 weeks off). Sham dogs received vehicle daily. At month 4, there was a significant decrease in bone volume in OHX animals (p < 0.05). Doses of ibandronate >/= 4.1 microg/kg/day stopped or completely reversed bone loss. Bone turnover (activation frequency) was significantly depressed in OHX dogs given ibandronate at the dose of 14 microg/kg/day. This was accompanied by significantly higher crystal size, a higher mineral-to-matrix ratio, and a more uniformly mineralized bone matrix than in control dogs. This finding lends support to the hypothesis that an increase in secondary mineralization plays a role in gain in BMD associated with bisphosphonate treatment. Moreover, intermittent and continuous therapies had a similar effect on bone volume. However, intermittent therapy was more sparing on bone turnover and bone mineral properties. Intermittent therapy could therefore represent an attractive alternative approach to continuous therapy.

Animals↗
PubMed1999

[Observation on effect of integrated Chinese and Western medicine in treating patients with peripheral atherosclerosis obliterans].

OBJECTIVE: To observe the therapeutic effect of integrated traditional Chinese and western medicine (TCM-WM) and its influence on plasma endothelin-1 (ET-1), nitric oxide (NO) and apoproteins. METHODS: Ninety patients of peripheral atherosclerosis obliterans (ASO) were divided into three groups randomly and treated with Salvia injection (SI), prostaglandin E1(PGE1) and SI + PGE1 respectively. The clinical manifestation of patients was observed dynamically, plasma level of ET-1, NO and apoprotein were tested before and after treatment by radioimmunoassay, Griss method, immuno-transmission method and enzyme method. RESULTS: The cure rate of the SI, PGE1 and TCM-WM group was 26.67%, 33.33% and 46.67% respectively, the effective rate of them was 26.67%, 40.00% and 43.33% respectively. The therapeutic effect of the TCM-WM group was better than that of the SI and PGE1 group, P < 0.01. The plasma level of ET-1, NO and apoprotein was positively correlated with the stage altering of ASO, it was normalized gradually when ASO was alleviating effectively. CONCLUSION: The TCM-WM therapy has good clinical effect in treating ASO. To observe the change of ET-1, NO and apoprotein level before and after treatment dynamically is helpful to judge the severity, progress of disease and effect of treatment, and has high clinical significance.

Aged↗
PubMed1999

[Influence of pre-operational medicated dachengqi granule on inflammatory mediator in tumor patients].

OBJECTIVE: To find a simple, effective, with few side effect method of pre-cleaning intestine for surgical operation of abdominal malignancy. METHODS: Thirty-five patients of abdominal malignant tumor were divided into two groups randomly and treated with Dachengqi Granule (DCQG) and routine western management (including oral taking antibiotics and enema with soap solution) respectively. Serum level of nitric oxide (NO), tumor necrosis factor (TNF), intercellular adhesive molecule-1 (ICAM-1), and enteric function recovering of patients were observed before operation, and 1, 3 and 7 days after operation. RESULTS: Time of borborygmus recovering and gas discharging after operation in the DCQG group was earlier than that of the control group, P < 0.05. Serum NO level was raised in both groups after operation, and reaching peak level at 3rd day post-operationally, as compared with pre-operation, P < 0.05, the difference between the two groups was insignificant. Serum TNF level lowered in both groups, but more apparent in the DCQG group, the inter-group difference was significant at the first day of operation, P < 0.05. Serum ICAM-1 level in the DCQG group decreased at the day 3 after operation with significant difference in comparison with pre-operational level, P < 0.05, but in the control group, change of ICAM-1 before and after operation was insignificant. The mean ICAM-1 level of the DCQG group at the day 3 post-operationally was significantly lower than that of the control group, P < 0.05. CONCLUSIONS: Compared with the routine management of western medicine, using DCQG for intestine pre-cleaning before operation could obviously lower the operation induced inflammatory reaction of tumor patients, reduce the secretion of inflammatory mediator, improve the recovery of enteric function and reduce the post-operational complication. Therefore, applying DCQG for pre-operational enteric preparing could provide a satisfactory effect in surgical operation of abdominal malignancy.

Adult↗
PubMed1999

[Relationship between endothelins, nitric oxide and other endothelial active factors and blood stasis syndrome in patients with atherosclerosis obliterans].

OBJECTIVE: To observe the levels of plasma endothelin (ET), nitric oxide (NO), intercellular adhesion molecule (ICAM) and other endothelial active factors, and to investigate the nature of atherosclerosis obliterans (ASO)-blood stasis Syndrome (BSS) from the point of vascular endothelia and molecules. METHODS: Ninety-eight patients with ASO-BSS were divided into 3 groups (mild, moderate and severe) and 3 clinical Syndrome subtypes (Qi stagnation BSS, Qi deficiency BSS and Damp-Heat BSS). The circulating endothelial count (CEC), ET, NO and other plasma active factors were determined by density gradient method, radioimmunoassay, enzyme immunoassay method. RESULTS: The patients with ASO-BSS had high CEC and ET levels, low levels of NO, and had alterations of hemorheology, particularly in those with severe BSS and Damp-Heat BSS. CONCLUSION: ASO-BSS patients have endothelial injuries, endothelial dysfunction, and alterations of hemorheology, which may be the pathogenetic mechanism of ASO-BSS. Observation on these parameter changes will be helpful to evaluate severity, to distinguish the clinical types in TCM, and to clarify the nature of BSS.

Adult↗
PubMed1999

[Studies on the lactate oxidase producing conditions by Edwardsiella tarda].

A bacterium producing lactate oxidase was re-screened from five strains based on previous researches. The lactate oxidase activity was the highest in strain L1 and this stain was chosen as the enzyme source. Morphological and physiological studies revealed that the bacterial strain L1 belongs to the Edwardsiella tarda Biogroup I. This stain is different from the reported strains Mycobacterium and Pediococcus, which produce lactate oxidase. The enzyme producing conditions were studied in shaking cultures, and the effects of initial pH, riboflavin, lactate and ammonia sulphate concentrations on the production were carried out respectively. The bacteria resource of enzyme is significant to pyruvate production by enzymatic method, and to the enzyme assay of lactate for medical diagnosis, and the application of enzyme electronic probe.

Culture Media↗
PubMed1998

Metabolic routing towards polyhydroxyalkanoic acid synthesis in recombinant Escherichia coli (fadR): inhibition of fatty acid beta-oxidation by acrylic acid.

Heterologous expression of the phaC1 gene from Pseudomonas aeruginosa, which encodes one of the polyhydroxyalkanoic acid synthases, in Escherichia coli impaired in fatty acid beta-oxidation results in polyhydroxyalkanoic acid accumulation when cells were cultivated on fatty acids. We evaluated the application of the fatty acid beta-oxidation inhibitor acrylic acid as a tool to channel intermediates of beta-oxidation to polyhydroxyalkanoic acid synthesis. Various E. coli strains affected in fatty acid metabolism and the wild-type strain harboring plasmid pBHR71 were analyzed with respect to polyhydroxyalkanoic acid accumulation in the presence of acrylic acid. The E. coli fadR mutant RS3097 revealed the strongest polyhydroxyalkanoic acid accumulation. The optimum inhibitory concentration of acrylic acid was 0.24 mg ml-1 and caused efficient channeling of intermediates of beta-oxidation to polyhydroxyalkanoic acid synthesis. Under these conditions and grown on decanoate E. coli RS3097 harboring plasmid pBHR71 revealed a polyhydroxyalkanoic acid accumulation contributing to about 60% of cellular dry weight.

Acrylates↗
PubMed1998

ICK1, a cyclin-dependent protein kinase inhibitor from Arabidopsis thaliana interacts with both Cdc2a and CycD3, and its expression is induced by abscisic acid.

Cyclin-dependent kinase (CDK) inhibitor genes encode low molecular weight proteins which have important functions in cell cycle regulation, development and perhaps also in tumorigenesis. The first plant CDK inhibitor gene ICK1 was recently identified from Arabidopsis thaliana. Although the C-terminal domain of ICK1 contained an important consensus sequence with the mammalian CDK inhibitor p27Kip1, the remainder of the deduced ICK1 sequence showed little similarity to any known CDK inhibitors. In vitro assays showed that recombinant ICK1 exhibited unique kinase inhibitory properties. In the present study we characterized ICK1 in terms of its gene structure, its interaction with both A. thaliana Cdc2a and CycD3, and its induction by the plant growth regulator, abscisic acid (ABA). ICK1 was expressed at a relatively low level in the tissues surveyed. However, ICK1 was induced by ABA, and along with ICK1 induction there was a decrease in Cdc2-like histone H1 kinase activity. These results suggest a molecular mechanism by which plant cell division might be inhibited by ABA. ICK1 clones were also identified from independent yeast two-hybrid screens using the CycD3 construct. The implication that ICK1 protein could interact with both Cdc2a and CycD3 was confirmed by in vitro binding assays. Furthermore, deletion analysis indicated that different regions of ICK1 are required for the interactions with Cdc2a and CycD3. These results provide a mechanistic basis for understanding the role of CDK inhibitors in cell cycle regulation in plant cells.

Abscisic Acid↗
PubMed1998

(+)-Abscisic acid metabolism, 3-ketoacyl-coenzyme A synthase gene expression, and very-long-chain monounsaturated fatty acid biosynthesis in brassica napus embryos

Microspore-derived embryos of Brassica napus cv Reston were used to examine the effects of exogenous (+)-abscisic acid (ABA) and related compounds on the accumulation of very-long-chain monounsaturated fatty acids (VLCMFAs), VLCMFA elongase complex activity, and induction of the 3-ketoacyl-coenzyme A synthase (KCS) gene encoding the condensing enzyme of the VLCMFA elongation system. Of the concentrations tested, (+)-ABA at 10 &mgr;M showed the strongest effect. Maximum activity of the elongase complex, observed 6 h after 10 &mgr;M (+)-ABA treatment, was 60% higher than that of the untreated embryos at 24 h. The transcript of the KCS gene was induced by 10 &mgr;M (+)-ABA within 1 h and further increased up to 6 h. The VLCMFAs eicosenoic acid (20:1) and erucoic acid (22:1) increased by 1.5- to 2-fold in embryos treated with (+)-ABA for 72 h. Also, (+)-8'-methylene ABA, which is metabolized more slowly than ABA, had a stronger ABA-like effect on the KCS gene transcription, elongase complex activity (28% higher), and level of VLCMFAs (25-30% higher) than ABA. After 24 h approximately 60% of the added (+)-[3H]ABA (10 &mgr;M) was metabolized, yielding labeled phaseic and dihydrophaseic acid. This study demonstrates that (+)-ABA promotes VLCMFA biosynthesis via increased expression of the KCS gene and that reducing ABA catabolism would increase VLCMFAs in microspore-derived embryos.

Journal Article↗
PubMed1998

[Determination of sunscreen agents in cosmetic products by reversed-phase high performance liquid chromatography].

A method for quantitative determination of eleven sunscreen agents (benzophenone-4,p-amino-benzoic acid, salicylic acid, benzophenone-3,phenyl salicylate, 4-methylbenzylidene camphor, octyl dimethyl p-amino-benzoate, isopropyl dibenzoylmethane, butyl methoxydibenzoylmethane, octyl methoxycinnamate, octyl salicylate) in cosmetic products is described. It was based on a high performance liquid chromatographic separation under the condition of isocratic elution with a mixture solution of methanol-THF-water-70% perchloric acid (200:200:160:0.1) by using a column packed with 10 microns YWG-C15 and UV detection. The recoveries (n = 6) were 94.1%-101% and the relative standard deviations(n = 6) for all eleven sunscreen agents were less than 5%. In addition, the results of analysis of 30 samples out of 103 samples of commercial suntan cosmetics performed are reported in this paper.

Chromatography, High Pressure Liquid↗
PubMed1998

[The changes of electrogastrogram and gastrointestinal pressure following cholecystectomy].

OBJECTIVE: To investigate the mechanism and pathophysiological changes after abdominal surgery. METHOD: Twenty-two patients after cholecystectomy were selected to perform cutaneous electrogastrography (EGG) at least one hour before operation, and the first, the second and the third day after operation respectively. On the operative and postoperative days, gastroduodenojejunal manometry was performed in 17 of the 2 patients. RESULT: The percentage of EGG normal frequency on the operative day was obviously lower than that on the preoperative day (P < 0.001), and the percentage of bradygastria on the operative day was obviously higher than that on the preoperative day (P < 0.01). The postoperative EGG amplitude was obviously lower than the preoperative one (P < 0.001), and did not recover after three days. The phase III of the migrating motor complex (MMC) appeared within 24 hours after operation, and first appeared at the duodenum. MMC III was most vigorous at the duodenum in recording period, and was less at the antrum. The contractile power and the area of MMC III at antrum after operation were obviously lower than at duodenum and upper jejunum (P < 0.01). On the third day after operation, the contractile power was lower than normal (P < 0.01). CONCLUSION: Gastrointestinal motility dysfunction after cholecystectomy is related to EGG amplitude, and not to EGG frequency. The recovery of antrum MMC III is later than that of small bowl, resulting in delayed gastric emptying. The MMC III of small bowl resums in early period after abdominal surgery. Postoperative ileum is due the decrease of MMC III contractile power and the area after abdominal surgery, which represent the ability of gastrointestinal contraction.

Adult↗
PubMed1997

Synthesis of poly(3-hydroxyalkanoates) in Escherichia coli expressing the PHA synthase gene phaC2 from Pseudomonas aeruginosa: comparison of PhaC1 and PhaC2.

In order to obtain functional expression of PHA synthase gene phaC2 from Pseudomonas aeruginosa in Escherichia coli, the coding region of phaC2 was subcloned, including the ribosomal binding site, into pBluescript SK- collinear to the lac promoter. This plasmid pBHR71-C2 enabled functional expression of phaC2 in E. coli LS1298 (fadB) under lac promoter control, leading to PHA accumulation, when grown in LB medium containing 0.5% (w/v) of various fatty acids (C8-C14). The strongest accumulation of PHA was observed, when dodecanoate was provided as carbon source, and PHA contributed to 15% of cell dry weight, which was composed of 35 mol% 3-hydroxydodecanoate, 60 mol% 3-hydroxydecanoate and 5 mol% 3-hydroxyoctanoate. Plasmid pBHR78, which contained both genes phaC1 and phaC2 from P. aeruginosa under lac promoter control in pBluescript SK- led in E. coli LS1298 to PHA accumulation, which contributed to 13% of cell dry weight, when cells were grown on decanoate. Only slight differences in PHA composition compared with either PhaC1 or PhaC2 were obtained. The weight average molecular masses of PHA purified from decanoate-grown cells of E. coli LS1298 expressing PhaC1 or PhaC2 alone or both PHA synthases, were 106 x 10(3), 70 x 10(3) or 67 x 10(3), respectively. This study clearly demonstrated that both PHA synthases from P. aeruginosa exhibit very similar properties resulting in similar extent of PHA accumulation, similar composition and molecular mass, when expressed in E. coli and that fatty acid beta-oxidation provides substrates for both PHA synthases.

Acyltransferases↗
PubMed1997

Long-term expression of Fos-related antigen and transient expression of delta FosB associated with seizures in the rat hippocampus and striatum.

Systemic administration of kainic acid (KA), an analogue of glutamic acid, causes limbic seizures and pathophysiological changes in adult rats that are very similar to human temporal lobe epilepsy. One of the earliest changes in gene expression after treatment with KA is the induction of immediate-early genes. The fos and jun families are frequently studied immediate-early genes that are induced by KA. Several groups, including ours, have recently reported that a 35-kDa Fos-related antigen (FRA) is induced for a protracted time by various stimuli. It has been suggested that this FRA is delta FosB, which has a molecular mass of approximately 35 kDa. The present study characterizes the long-term expression of FRA and delta FosB after systemic treatment with KA. Immunocytochemistry and western blot analysis using an antibody that cross-reacts with all known FRAs showed that a 35-kDa FRA was induced at high levels in both the hippocampus and striatum for up to 1 month by KA. A semiquantitative PCR analysis showed that delta FosB was induced by KA, but its expression lasted for only 6 h. This result was also verified by northern blot analysis. These results suggested that the 35-kDa FRA with long-term elevated levels seen with western blot analysis and immunocytochemistry is a new species of the FRA and not delta FosB. The long-term expression of FRA in both the hippocampus and striatum may be associated with the pathophysiological changes after KA administration.

Animals↗
PubMed1997

Secondary hyperparathyroidism and vitamin D receptor binding to vitamin D response elements in rats with incipient renal failure.

The pathogenesis of secondary hyperparathyroidism in early renal failure is poorly understood. In the study presented here, parathyroid hormone and GFR in rats with mild renal failure of various durations are evaluated. Parathyroid hormone increased significantly 3 days after nephrectomy and peaked at 2 wk, despite reduction in GFR of < 50%. Parathyroid hormone remained elevated, but there was no difference in serum levels of calcium, phosphorus, and calcitriol between the nephrectomized and sham-operated rats. There were also no differences in both intestinal and kidney vitamin D receptor concentrations between the two groups. Histomorphometric analysis of bone at 6 wk revealed significant increase in osteoid thickness, osteoblast number, erosion surface with osteoclasts, and erosion depth. Employing electrophoretic mobility shift assay, we consistently observed a significant reduction in kidney calcitriol-receptor complex binding to mouse osteopontin vitamin D response element (-70.2 +/- 4.9%, P < 0.001). Western blot analysis also revealed a significant reduction in at least one retinoid X receptor isoform. In conclusion, biochemical and histological evidence of secondary hyperparathyroidism develops in rats with mild renal failure, despite normal calcium, phosphorus, calcitriol, and vitamin D receptor concentrations. These rats also have evidence of reduced renal vitamin D receptor binding to nuclear response elements. This finding, possibly an important early factor in the pathogenesis of secondary hyperparathyroidism, could also play a role in the development of compensatory renal growth of the remnant kidney.

Animals↗
PubMed1997

[Magnesium and calcium concentration of peripheral serum and mononuclear cells in patients with pregnancy induced hypertension].

OBJECTIVE: To evaluate the magnesium and calcium concentration of peripheral serum and mononuclear in patients with pregnancy induced hypertension (PIH). METHODS: Twenty-six patients with PIH and 27 healthy women in their late pregnancy were studied. The serum and mononuclear cells magnesium and calcium contents were measured with atomic absorption spectrophotometry (fire atomization). RESULTS: When compared with the healthy women in their late pregnancy, (1) the peripheral serum magnesium and calcium contents in patients with PIH decreased significantly (P < 0.01 and P < 0.05), (2) the magnesium contents of the peripheral mononuclear cells in patients with moderate and severe degrees of PIH decreased significantly (P < 0.001 and P < 0.01), (3) the calcium contents of the peripheral mononuclear cells in patients with moderate and severe degrees of PIH decreased significantly (P < 0.01 and P < 0.05). CONCLUSION: The decrease of magnesium and calcium concentration may be one of the important factors responsible for the pathophysiologic changes of PIH.

Adult↗
PubMed1996

Calcitonin prevents bone loss but decreases osteoblastic activity in ovariohysterectomized beagle dogs.

The antiresorptive effects of calcitonin are well documented. Recent in vitro and in vivo evidence points to an anabolic effect of calcitonin on osteoblasts. To assess the value of calcitonin in preventing the rapid and early bone loss after cessation of ovarian function and to investigate its effects on osteoblasts in vivo, 32 dogs were ovariohysterectomized (OHX) and 32 dogs were sham-operated (Sham). After the surgeries, half of the OHX and Sham dogs received every-other-day subcutaneous injections of human calcitonin (0.25 mg/dog/d), and the remaining dogs were given vehicle. Half of the animals had a bone biopsy at week 2 and were euthanized thereafter; the other half of the animals underwent a bone biopsy at month 1 and were euthanized at month 4. Blood drawings were done at baseline and at the time of each bone biopsy. Calcitonin prevented the increase in erosion depth seen in OHX animals and prevented the cancellous bone loss observed at 2 weeks and at 1 and 4 months. Calcitonin did not affect bone volume in Sham dogs. However, treatment with calcitonin induced a decrease in mineralizing surfaces and bone formation rates at the bone surface and cell level and an increase in mineralization lag time in both Sham and OHX animals without significantly affecting osteoblast number. This finding indicates that the negative effect of calcitonin on bone mineralization is not solely the result of a decrease in bone turnover. The data show that calcitonin, because of its antiresorptive effects, can prevent bone loss after cessation of ovarian function. However, short-term treatment with calcitonin does not stimulate osteoblast activity; on the contrary, it exerts a negative effect on osteoblastic bone formation and mineralization. Long-term studies are needed to investigate whether this unwanted effect of calcitonin on osteoblasts in vivo represents a transitory or persistent phenomenon.

Animals↗