Biomedical subjects
Publications and source records attributed to R Guo.
A HPLC method has been used for the determination of paeonol in Jiawei Xiaoyao Granules. The method is simple and accurate. The average recovery is 96.48% and relative standard deviation 1.11%. The method can be used for quantitative analysis of these granules.
OBJECTIVE: To compare the guanosine contents in various products of Pinellia Rhizoma processed by different amounts of ginger and alum. METHOD: Using the technology of HPLC. RESULT: The guanosine contents in the two products of Pinellia Rhizoma processed in line with the pharmacopoeial method and orthogonal method respectively are very close to each other and change every little as compared with raw Pinellia Rhizoma. But the contents in the products of Pinelliae Rhizoma processed in other ways (digged in alum solution or in ginger Juice decocted with ginger juice, etc.) are much less than those of raw Pinellia Rhizoma. CONCLUSION: There are no obvious differences in guanosine contents between Pinellia Rhizoma processed by orthogonal technology and Pinellia Rhizoma processed by pharmacopoeial method. Processing technology has considerable influence on the water soluble components of Pinellia Phizoma.
OBJECTIVE: Hirudin is an extremely efficient and specific thrombin inhibitor. It is clinically used to prevent the formation of thrombus. In this research the hirudin gene was put into yeast system for expression to evaluate the feasibility of artificially synthesized gene expressed in eukaryotic system and study the factor affecting expression level. METHODS: According to the amino acid sequence of hirudin variant 1 (HV1), the genetic code saccharomyces cerevisiae was used to design and synthesize the HV1 gene. Amplified by PCR, it was inserted into cloning vector pBS-SK(+) and sequenced. Ligation with the signal peptide gene of yeast alpha factor the correct HV1 gene was inserted into yeast expression vector pYC-DE. The recombinant plasmid was transformed into the cell of S. cerevisiae BJ1990 to carry out the primary expression experiment. RESULTS: In cultured supernatant of screened positive clone the hirudin activity was detected to be 30 ATU/ml. The expression level was higher than HV2 in yeast and HV1 in prokaryotic system. The N terminal amino acid sequence completely matches with natural hirudin. CONCLUSIONS: It was proved by this study that the synthesized hirudin gene had been expressed in yeast successfully. This result showed that it was a better way to carry out the expression in yeast using synthesized HV1 gene and a stronger promoter.
OBJECTIVE: To study the correlation between cholelithiasis and the infection of HBV. METHOD: 32 formalin-fixed and paraffin-embedded gallbladder samples of cholelithiasis patients and 20 gallbladder samples of non-cholelithiasis patients were investigated using the polymerase chain reaction-Ethidium bromide (PCR-EB) assay. The 52 patients were positive to HBV serologic markers. RESULT: The results showed that HBV-DNA was found in 13 gallbladder samples of 32 cholelithiasis patients (40.63%), significantly higher than that in 3 gallbladder samples of 20 non-cholelithiasis patients (15%). CONCLUSION: The infection of HBV and the formation of cholelithiasis are correlated.
The construction of poliovirus chimera is an useful way to investigate the antigenic structure conformation of poliovirus. In this research, the poliovirus chimera containing a piece of antigenic fragment of hepatitis A virus was constructed for analysis of poliovirus antigenic structure conformation. Depending on the characterization of this chimera, the conformation of poliovirus neutralization antigenic site I in VP1 was analyzed, and that the possible influence of hepatitis A virus antigenic fragment inserted to the structure conformation of poliovirus antigen was also investigated.
Donkey-hide glue, antler glue, tortoise shell glue and their forgeries were identified by the analysis method of circular dichroism(CD) in this paper. The standard spectra and data were set up. The method is simple, fast and accurate.
The change of absorption spectrum of meso-Tetra (4-sulfophenyl) Porphyrin (TPPS) in microemulsion system (Triton X-100-nonane-pentanol-water) was studied. The electric dissociation constants (Ka ) and dimerization constants (KD) were calculated. It was shown that Ka of TPPS is added but KD of TPPS is decreased in microemulsion system as compared with that in aqueous solution.
The distribution and co-localization of nitric oxide synthase (NOS) and vasoactive intestinal polypeptide (VIP) were examined by means of immunohistochemistry and NADPH diaphorase (NADPH-d) histochemistry in the gut of patients with Hirschsprung's disease. In the normoganglionic segment, many nitrergic nerve cells were localized in Auerbach's plexus and nerve fibres were observed preferentially in the circular muscle. The submucosal nitrergic nerve cells were mainly situated in Schabadasch's plexus with occasional cells demonstrable in Meissner's plexus. NOS and VIP were co-localized in most ganglion cells of Auerbach's plexus. In the oligoganglionic segment, a marked reduction of NOS- and VIP- positive nerve cells and fibres was noticed in both the myenteric and submucosal plexuses, and nitrergic fibres had disappeared in the inner layer of the circular muscle. In the aganglionic segment, NOS and VIP were revealed only in extrinsic nerve fasciculi and rami and co-localized in a few fibres. From these observations, the inner layer of the circular muscle of the oligoganglionic segment and the whole of the muscularis propria of the aganglionic segment were considered to be totally lacking in nitrergic innervation. Nitrergic nerves of the human colon comprise both intrinsic and extrinsic elements and the majority of intrinsic nitrergic nerve cells contain VIP. Very low numbers of extrinsic nitrergic fibres contain VIP.
The 18S-5.8S-26S rDNA and 5S rDNA loci have been mapped physically by fluorescent in-situ hybridization to the chromosomes of Phalaris coerulescens. The biotin-labelled heterologous 18S-5.8S-26S rRNA probe (pTa71) detected one locus, which corresponded to the secondary constriction (nucleolar organizer) on the long arm of the satellited chromosome II. The homologous 5S rDNA probe (Bam2.12) detected two pairs of 5S rRNA gene clusters which were localized at two different non-satellited chromosomes, one near the telomere on the short arm of the chromosome I, which is the largest chromosome of the complement, and the other about 42% out on the long arm of the chromosome III. A BamHI fragment containing the 5S rRNA gene, has been isolated and characterized. The 5S rDNA repeat unit is 309 bp in length, consisting of 121 bp highly conserved coding region and 188 bp variable spacer region. The karyotype of Phalaris coerulescens is characterized by the similar size of chromosomes within the group 2, group 3, or group 4. This study represents the first step towards the understanding the genome organization of Phalaris coerulescens and provides reliable markers for chromosome identification in this grass, an important species as a model system for the study of self-incompatibility in grasses.
OBJECTIVE: Vitamin E, the most potent naturally occurring lipid soluble antioxidant has been suggested to possess both anti-inflammatory and analgesic activity in humans. This double blind and randomised study used a broad spectrum of clinical and laboratory parameters to investigate whether there was any additional anti-inflammatory or analgesic effects, or both, of orally administered alpha-tocopherol in rheumatoid arthritis patients who were already receiving anti-rheumatic drugs. METHODS: Forty two patients were enrolled and treated with alpha-tocopherol (n = 20) at a dose of 600 mg twice a day (2 x 2 capsules) or with placebo (n = 22) for 12 weeks. The following parameters were measured: (1) Three clinical indices of inflammation--the Ritchie articular index, the duration of morning stiffness, and the number of swollen joints; (2) three measures of pain--pain in the morning, pain in the evening, and pain after chosen activity; (3) haematological and biochemical measures of inflammatory activity; (4) assays for the oxidative modification of proteins and lipids. RESULTS: All laboratory measures of inflammatory activity and oxidative modification were unchanged. Furthermore, the clinical indices of inflammation were not influenced by the treatment. However, the pain parameters were significantly decreased after vitamin E treatment when compared with placebo. CONCLUSION: The results provide preliminary evidence that vitamin E may exert a small but significant analgesic activity independent of a peripheral anti-inflammatory effect, but which complements standard anti-inflammatory treatment.
The presence of a cation-sensing mechanism in osteoblasts is suggested by the ability of specific cations to stimulate osteoblastic proliferation in culture and to induce de novo bone formation in some experimental models. Our study examines whether extracellular cations stimulate osteoblasts through the recently identified G protein-coupled calcium receptor (CaR). We found that CaR agonists, calcium (Ca2+), gadolinium (Gd3+), aluminum (Al3+), and neomycin, stimulated DNA synthesis in murine-derived MC3T3-E1 preosteoblasts, whereas magnesium (Mg2+), nickel (Ni2+), cadmium (Cd2+), and zinc (Zn2+) had no effect. With the exception of Mg2+, the cation specificities and apparent affinities were similar to that reported for CaR. CaR agonists also stimulated DNA synthesis in C3HT10(1/2) fibroblasts, but not in mesangial PVG, CHO, hepatic HTC, COS-7 cells, or malignant transformed ROS17/2.8 and UMR-106 osteoblasts. In addition, similar to other growth factors, CaR agonists activated transcription of a serum response element luciferase reporter construct (SRE-Luc) stably transfected into MC3T3-E1 osteoblasts, but had no effect on SRE-Luc transfected into CHO and COS-7 cells. We were unable to detect CaR expression by Northern analysis using a mouse CaR-specific probe or to amplify CaR mRNA by reverse transcribed polymerase chain reaction in MC3T3-E1 osteoblasts. These findings suggest that an extra-cellular cation-sensing mechanism is present in murine-derived osteoblasts that is functionally similar to but molecularly distinct from CaR.
Inactivating mutations of the neutral endopeptidase, PEX, have been identified as the cause of X-linked hypophosphatemia (XLH). Though the function of PEX is unknown, current information suggests that impaired renal phosphate conservation in XLH is due to the failure of PEX to either degrade an undefined phosphaturic factor or activate a novel phosphate-conserving hormone. The physiologically relevant target tissue for the XLH mutation has not been identified. An apparent intrinsic defect of osteoblast function in XLH implicates bone as a possible site of PEX expression. In the current investigation, we employed a polymerase chain reaction (PCR) strategy to amplify a PEX cDNA from a human bone cell cDNA library. We found that the human PEX cDNA encodes a 749 amino acid protein belonging to the type II integral membrane zinc-dependent endopeptidase family. The predicted PEX amino acid sequence shares 96.0% identify to the recently cloned mouse Pex cDNA and has 27-38% identity to other members of the metalloendopeptidase family. Using reverse transcriptase (RT)-PCR with PEX-specific primers, we detected PEX transcripts in both human osteosarcoma-derived MG-63 osteoblasts and in differentiated mouse MC3T3-E1 clonal osteoblasts but not in immature MC3T3-E1 preosteoblasts. The association of impaired mineralization of bone in XLH and the apparent developmental stage-specific expression of PEX in osteoblasts suggest that bone is a physiologically relevant site of PEX expression and that PEX may play an active role in osteoblast-mediated mineralization.
The geniposide and paeoniflorin in Jiaowei Xiaoyao Pills were separated and determined by HPLC, with a C18 column and a mixture of CH3CN-0.1% H3PO4(13:87) as mobile phase. The method is simple, rapid and accurate. The components have a good linearity, and the average recovery with RSD(n = 5) is 101.81% + 2.38% for geniposide and 98.75% + 1.95% for paeoniflorin.
BACKGROUND AND AIMS OF THE STUDY: Mitral valve prolapse due to floppy mitral valve (MVP/FMV) is a common valvular abnormality with a variable clinical course. Flail mitral valve leaflet resulting in severe mitral regurgitation is a complication of MVP/FMV. METHODS: In order to understand the structural correlates of flail mitral valve leaflet in MVP, we reviewed the morphologic characteristics of the mitral valve by transesophageal echocardiography (TEE) in 72 patients (24 normal; 26 mitral valve prolapse; 22 flail mitral valve leaflet). RESULTS: Compared with the normal group, the mitral valve prolapse group had greater anterior and posterior mitral valve leaflet thickness and anterior mitral valve leaflet length. Patients with flail mitral valve leaflets as a complication of FMV had greater anterior and posterior mitral valve leaflet length and posterior mitral valve leaflet thickness compared with MVP patients without flail mitral valve leaflets. Posterior mitral valve leaflet length was the only echocardiographic independent predictor of flail mitral valve leaflet. Older FMV patients with increased mitral valve leaflet length and thickness are predisposed to flail mitral valve leaflets and severe mitral regurgitation. CONCLUSIONS: TEE may identify patients with MVP/FMV with the greatest structural abnormalities who are at risk for complications such as flail mitral valve leaflet(s).
To evaluate the ability of color Doppler flow imaging (CDFI) to detect deep venous thrombosis (DVT), which is difficult to diagnose clinically, 67 limbs of 60 patients who presented with clinical signs strongly indicative of DVT during the period between June 1988 and June 1992, were examined. The iliac, common femoral, and superficial femoral veins were assessed with the patient in the supine position, and the popliteal vein was examined with the patient prone. Gentle but firm compression with the transducer probe was used to test for the presence of DVT. Ascending contrast venograms were also obtained within 24 h after the ultrasound procedure, with venography being used as the standard for comparison with CDFI. DVT was identified in 63 limbs by contrast venography and in 62 limbs by CDFI. The sensitivity and specificity of CDFI were 98.4% and 100%, respectively, while the positive and negative predictive values were 100% and 80%, respectively. The thromboses were classified into three patterns: the filling type, the local type, and mural thrombus, detected in 63%, 27%, and 10%, of the limbs respectively, with the filling type being the most common in this series. The results of our study illustrated that CDFI is highly sensitive and specific for detecting symptomatic DVT and that it should be gradually substituted for venography in such patients.
Early atherosclerotic changes in the carotid artery and thoracic aorta have been examined by high-frequency ultrasound measuring of intimal-medial thickness and stiffness. Whether changes in stiffness and thickness occur in parallel and whether the determinants of stiffness and thickness in the two vessels are similar is unknown. To examine the relation between ultrasonographic measures of atherosclerosis in the carotid and the thoracic aorta, 146 patients aged 20 to 84 years (mean 54 years) were studied by both transesophageal echocardiography (TEE) and carotid duplex scanning. From two-dimensionally derived M-mode recordings of the thoracic aorta and high-frequency B-mode imaging of the common carotid, the intimal-medial thickness was measured along with diastolic and systolic diameters for calculation of stiffness. Interobserver and intraobserver variability of carotid and aortic intimal-medial thickness and diameter were low. There was a good relation between carotid and aortic intimal-medial thickness (r = 0.69; p=0.0001). Age was the major independent determinant of thickness in both vessels. Carotid and aortic stiffness, as measured by Peterson's elastic modulus, were less closely related (r=0.51; p=0.0001). Age was the only independent predictor of stiffness in both vessels. In conclusion, structural ultrasonographic manifestations of early atherosclerosis in the carotid artery and thoracic aorta are closely related. Large population studies measuring only carotid intimal-medial two-thickness may reflect atherosclerotic changes occurring throughout the vascular bed.
Posterior displacement of the mitral valve with billowing into the left atrium has been the major echocardiographic criterion used for the diagnosis of mitral valve prolapse (MVP). However, the current criteria are limited by the influence of hemodynamic factors on the degree of prolapse, whereas complications such as mitral regurgitation, endocarditis, and need for surgery have been associated with redundancy or thickening of the leaflets. Sixty-eight normal subjects (mean age, 40 years; range, 18 to 76 years) were compared with 58 patients with MVP (mean age, 37 years, range, 18 to 83 years). Leaflet displacement across the annular plane in the parasternal long-axis view was mandatory for the diagnosis of MVP. Transthoracic echocardiographic measurements of anterior and posterior leaflet thickness, leaflet length, and chordal length were made from the parasternal long-axis view and the mitral annular diameter, from the apical four-chamber and two-chamber views. The MVP group had greater anterior thickness (4.1 +/- 0.4 mm vs 5.3 +/- 0.7 mm; p = 0.0001), posterior thickness (3.2 +/- 0.4 mm vs 4.7 +/- 0.9 mm; p = 0.0001), anterior length (22.8 +/- 2.0 mm vs 25.7 +/- 1.7 mm; p = 0.0001), posterior length (12.8 +/- 1.0 mm vs 15.7 +/- 2.5 mm; p = 0.0001), chordal length (25.6 +/- 2.7 mm vs 28.0 +/- 2.5 mm; p = 0.0001), and annular diameter (29.1 +/- 1.5 mm vs 31.3 +/- 2.6 mm; p = 0.0001). Of the MVP group, >80% had at least one abnormality identified and >50% had at least two abnormalities. In addition, patients with MVP with significant regurgitation had greater anterior thickness (5.2 +/- 0.7 mm vs 5.8 +/- 0.8 mm; p = 0.015), posterior thickness (4.5 +/- 0.9 mm vs 5.3 +/- 0.7 mm; p = 0.024), posterior length (15.1 +/- 1.6 mm vs 17.9 +/- 4.2 mm; p = 0.004), and annular diameter (36.0 +/- 2.0 mm vs 33.3 +/- 2.1 mm; p = 0.0001). The majority of patients with floppy mitral valves resulting in MVP have structural abnormalities that may be defined by echocardiography. A spectrum of floppy valve structure is demonstrated by echocardiography, with mitral regurgitation occurring more frequently in patients with multiple and more severe anatomic abnormalities. In addition to the presence of prolapse and regurgitation, the assessment of leaflet thickness, leaflet length, annular diameter, and chordal length is fundamental to the definition and stratification of patients with MVP associated with the floppy mitral valve.
The contents of paeonol in prepared pieces of carbonized bark of Paeonia suf fruticosa were determined by HPLC. The result shows that the contents of paeonol decrease with the rise of temperature and the extension of time in processing.