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F P Wang

Publications and source records attributed to F P Wang.

10 recordsLinked to original sources
PubMed1992

Mammalian cells that express Bacillus cereus phosphatidylinositol-specific phospholipase C have increased levels of inositol cyclic 1:2-phosphate, inositol 1-phosphate, and inositol 2-phosphate.

Phosphatidylinositol-specific phospholipase C (PtdIns-PLC) of Bacillus cereus catalyzes the conversion of PtdIns to inositol cyclic 1:2-phosphate and diacylglycerol. NIH 3T3, Swiss mouse 3T3, CV-1, and Cos-7 cells were transfected with a cDNA encoding this enzyme, and the metabolic and cellular consequences were investigated. Overexpression of PtdIns-PLC enzyme activity was associated with elevated levels of inositol cyclic 1:2-phosphate (2.5-70-fold), inositol 1-phosphate (2-20-fold), and inositol 2-phosphate (3-20-fold). The increases correlated with the levels of enzyme expression obtained in each cell type. The turnover of phosphatidylinositol (PtdIns) was also increased in transfected CV-1 cells by 13-fold 20 h after transfection. The levels of PtdIns, phosphatidic acid, diacylglycerol, or other inositol phosphates were not detectably altered. Expression of bacterial PtdIns-PLC decreased rapidly after 20 h implying that either the increased PtdIns turnover or the accumulation of inositol phosphates was detrimental to cells and that by some adaptive mechanism enzyme expression was suppressed.

3T3 Cells↗
PubMed1992

[HPLC determination of salidroside in the roots of Rhodiola genus plants].

This paper reports a high performance liquid chromatographic (PHLC) method for the determination of salidroside in 10 samples of the plants of Rhodiola crenulata, R. alterna, R. brevipetiolata, R. yunnanensis and R. quadrifida as well as extracts of R. crenulata. Determination was carried out under the following conditions: column (mu Bondapak ODS, 10 microns, 3.9 mm x 300 mm), mobile phase (methanol-water, 2:8), flow rate (1.0 ml/min), detector (Waters 484, wavelength 276 nm). External standard method was used. The results show that HPLC is a useful tool for the quantitative analysis of salidroside in the plants of Rhodiola genus and the extracts of R. crenulata.

Chromatography, High Pressure Liquid↗
PubMed1992

[Studies on the chemical components of Rhodiola crenulata].

Six chemical components I-IV were isolated from the roots of Rhodiola crenulata (Crassulaceae). Five (I-V) of them were identified as known salidroside (I), p-tyrosol(II), pyrogallol, gallic acid, and beta-sitosterol, based on comparison of its Rf(TLC), mmp and spectral data with those of authentic samples. The sixth component was found to be a new delta 1-isopentenyl-3-O-beta-D-glucopyranoside and named crenulatin(VI). Its structure was confirmed on the basis of its spectral data (IR, MS, 1H- and 13C-NMR).

Coumarins↗
PubMed1992

[Revision of structure of peimisine].

From the bulbs of Fritillaria siechuanica cultivated in Sichuan province, 5 alkaloids including peimisine (III) were isolated. Structure of peimisine reported in reference (2) was revised as 2 based on 2D-NMR (1H-1H, 1H-13C COSY and NOE), and FR-5 was proved to be peimisine on the basis of their melting point and TLC behavior. It is worthy of noting that 1) configuration of the oxygen at the C-17 in hupehenisine 3 is possibly erroneous; 2) both songbaisine 4 (A or B) and peimisine 2 should be the same compound on the basis of comparison of their 13C NMR data (Table 3) and 1H NMR spectra; 3) configuration of the oxygen atom at C-17 in the jervine-type steroidal alkaloids can not be safely proved by their IR, MS and the chemical shifts of some protons such as the methyls without the X-ray diffraction analysis, or the NOE technique and the 13C NMR method.

Alkaloids↗
PubMed1992

Quantitative stress-redistribution thallium-201 SPECT using prone imaging: methodologic development and validation.

Prone 201Tl myocardial perfusion SPECT has been shown to improve left ventricular inferior wall counts compared to supine imaging, thus minimizing diaphragmatic attenuation. Prone SPECT quantitative normal limits were developed and prospectively applied to 36 patients who had coronary angiography. The prone imaging table used had a cut-out under cardiac area which increased the average myocardial counts by 10.7% compared to prone SPECT through the standard table. Overall specificity and sensitivity were 80% and 93%, respectively. For the right, left circumflex and left anterior descending coronary arteries, the specificities were 94%, 71%, and 94%; and sensitivities were 88%, 89% and 78%, respectively. The normalcy rate in 55 normal patients was 89%. Incidence and the severity of patients motion in 200 prone SPECT studies were compared to 200 supine SPECT studies. Mild and severe motion occurred in 12% and 4% of the supine studies and in only 3.5% and none of the prone studies, respectively. When compared to supine SPECT, prone SPECT had higher (p less than 0.01) regional counts/pixel in the inferior wall and septum, but required an average increase of 2.9 +/- 1.0 cm in camera to chest wall distance and resulted in a reduction of total myocardial counts. Prone SPECT provides an alternative approach for patients who cannot tolerate supine imaging. It should be considered when inferior wall defects on supine imaging pose a diagnostic dilemma and when motion on supine imaging necessitates repeat acquisition.

Aged↗
PubMed1991

Frequency of late reversibility in stress-redistribution thallium-201 SPECT using an early reinjection protocol.

To assess the efficacy of an early thallium-201 reinjection protocol for reducing the need for late redistribution imaging, the frequency of thallium-201 late reversibility was prospectively assessed in 62 patients who had stress-redistribution thallium-201 studies by single-photon emission computerized tomography (SPECT), and who received 1 mCi of thallium-201 reinjection immediately following stress tomographic acquisition. These patients also demonstrated greater than or equal to 2 segments with nonreversible defects at 4-hour imaging and underwent late (18-to 72-hour) redistribution imaging. When the criterion of late reversibility was defined as greater than or equal to 1 segment with a 4-hour nonreversible defect demonstrating late reversibility, late reversibility was present in 36 (58%) of the 62 patients and in 88 (24%) of 368 SPECT segments. When the criterion of greater than or equal to 2 segments was used, late reversibility was found in 21 (34%) of the 62 patients and in 73 (20%) of the 368 segments. Of the 21 patients who had greater than or equal to 2 late reversible segments, 12 (57%) exhibited late reversibility in greater than or equal to 3 segments. The frequency of detected reversible defects increased from 32% by 4-hour imaging to 48% by combined 4-hour and late imaging (p less than 0.0001). The patients who demonstrated late reversibility could not be distinguished from those who had only late nonreversible defects by analysis of the clinical, exercise, and electrocardiographic (ECG) variables.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗