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Biomedical subjects

Y H Liu

Publications and source records attributed to Y H Liu.

At least 55 records · Page 3Linked to original sources
PubMed2001

Use of dexamethasone on the prophylaxis of nausea and vomiting after tympanomastoid surgery.

OBJECTIVE: The aim of this study was to evaluate the prophylactic effect of dexamethasone on postoperative nausea and vomiting (PONV) in patients undergoing tympanomastoid surgery. STUDY DESIGN: Eighty patients (n = 40 in each of two groups) undergoing tympanomastoid surgery under general anesthesia were enrolled in this randomized, double-blind, placebo-controlled study. METHODS: After tracheal intubation, group 1 received 10 mg dexamethasone intravenously, whereas group 2 received saline intravenously. Several parameters concerning with the occurrence of PONV were evaluated. RESULTS: We found that dexamethasone reduced the total incidence of nausea and vomiting by 45%, with a 95% confidence interval of 26% to 64% (P <.001). Furthermore, dexamethasone reduced the incidence of vomiting episodes >4 times and the incidence of patients requiring rescue antiemetics (P <.05). CONCLUSION: Dexamethasone at a dosage of 10 mg administered intravenously is effective in preventing PONV in patients undergoing tympanomastoid surgery.

Adult↗
PubMed2001

Purification and characterization of a dimethoate-degrading enzyme of Aspergillus niger ZHY256, isolated from sewage.

A dimethoate-degrading enzyme from Aspergillus niger ZHY256 was purified to homogeneity with a specific activity of 227.6 U/mg of protein. The molecular mass of the purified enzyme was estimated to be 66 kDa by gel filtration and 67 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The isoelectric point was found to be 5.4, and the enzyme activity was optimal at 50 degrees C and pH 7.0. The activity was inhibited by most of the metal ions and reagents, while it was induced by Cu(2+). The Michaelis constant (K(m)) and V(max) for dimethoate were 1.25 mM and 292 micromol min(-1) mg of protein(-1), respectively.

Aspergillus niger↗
PubMed2001

Homocyclotirucallane and two dihydrophenanthrenes from Spiranthes sinensis.

A novel homocyclotirucallane, sinetirucallol (1), and two additional new dihydrophenanthrenes, sinensols G (2) and H (3), were isolated from the aerial parts of Spiranthes sinensis (Pers.) Ames. Their structures were determined by various spectral analyses, including MS and two-dimentional nuclear magnetic resonance techniques. The structure of compound 1 was further confirmed by single-crystal X-ray analysis. The absolute configuration of 1 was determined by modified Mosher's method.

Acetylation↗
PubMed2001

New cyclopropyl-triterpenoids from the aerial roots of Ficus microcarpa.

Four new cyclopropyl-triterpenes, 27-nor-3beta-hydroxy-25-oxocycloartane (1), (22E)-25,26,27-trinor-3beta-hydroxycycloart-22-en-24-al (2), 3beta-acetoxy-15alpha-hydroxy-13,27-cyclours-11-ene (3), 3beta-acetoxy-12alpha-formyloxy-13,27-cycloursan-11alpha-ol (4), together with (23E)-27-nor-3beta-hydroxycycloart-23-en-25-one (5) were isolated from the aerial roots of Ficus microcarpa. Compounds 3 and 4 are rare 13,27-cycloursane-type triterpenes. Their structures were elucidated by spectroscopic and chemical methods.

Crystallography, X-Ray↗
PubMed2001

Analysis of loss of heterozygosity on chromosomes 10q, 11, and 16 in medulloblastomas.

OBJECT: The loss of genetic material from specific chromosome loci is a common feature in the oncogenesis of tumors and is often indicative of the presence of important tumor suppressor genes at these loci. Recent molecular genetic analyses have demonstrated frequent loss of chromosomes 10q, 11, and 16 in medulloblastomas. The aim of this study was to localize the targeted deletion regions on the three aforementioned chromosomes in medulloblastomas. METHODS: Loss of heterozygosity (LOH) was examined on chromosomes 10q, 11, and 16 in a series of 22 primary and two recurrent medulloblastomas by using polymerase chain reaction-based microsatellite analysis. The DNA extracted from the tumors and corresponding normal blood samples were amplified independently in the presence of radioactively labeled microsatellite primers, resolved by denaturing gel electrophoresis and processed for autoradiography. The DNA obtained from control blood samples that displayed allelic heterozygosity at a given microsatellite locus were considered informative. Loss of heterozygosity was inferred when the allelic signal intensity of the tumor sample was reduced by at least 40%, relative to that of the constitutional control. The LOH analysis demonstrated that deletions of chromosomes 10q, 11p, and 16q are recurrent genetic events in the development of medulloblastomas. Three subchromosomal regions of loss have been identified and are localized to the deleted in malignant brain tumors 1 [DMBT1] gene site on chromosomes 10q25, 11p13-11p15.1, and 16q24.1-24.3. CONCLUSIONS: These results indicate that DMBT1 is closely associated with the oncogenesis of medulloblastomas and highlight regions of loss on chromosomes 11p and 16q for further fine mapping and cloning of candidate tumor suppressor genes that are important for the genesis of medulloblastoma.

Adolescent↗
PubMed2001

[Production of transgenic lamb integrated with modified human anti-trypsin gene].

This experiment is to produce the human mAAT(modified anti-trypsin) which cures the emphysema specifically through mammalian galactophore of transgenic goat. 56 goats were selected as donor for superovulation by FSF + LH microinjection in this experiment. The pronucleic embryos were injected with human mAAT gene after fertilization in vivo, and transferred to the donors or receptors directly. The superovulation was better in March and May than in December with the number of ovulation of 19.50, 21.70 and 16.06, and number of fertilized embryos of 4.31, 6.48 and 3.57 per-animal respectively. The pregnant rates were 18.18% and 25% respectively after transferred to donors and receptors with natural estrus. The donors also can be used as the embryo receptor with no remarkable decrease of pregnant rate. 29 lamb were labored. 4 positive transgenic lamb were checked by PCR, PCR-Southern and Southern analysis. The integrated efficiency of foreign DNA was 13.79% with microinjection of high copy number of foreign DNA fragment.

Animals↗
PubMed2001

The health status of rural and urban ambulatory elderly in Taipei County.

BACKGROUND: To study the differences in the health status of rural and urban ambulatory elderly in Taipei County. METHOD: Non-compulsory general health check-up for elderly people over 65 years old in rural and urban areas. The content of the health examination included past medical history, health behavior, physical examination, laboratory examination, electrocardiogram and x-ray. Chi square test, t-test and logistic regression were applied for analysis. Risk factors relating to the cardiovascular system were included in the study. Gender differences affecting the prevalence of diseases and health behavior were also considered in the analysis. RESULTS: Significantly higher proportions of the rural elderly men smoked, drank alcohol, and had hypertension and impaired renal function. On the other hand, higher proportions of rural elderly women were obese and had diabetes, hypertension and renal impairment. The mean plasma glucose level of newly-diagnosed diabetic patients in the rural area was significantly higher than that in the urban area (p < 0.05). Diabetes, obesity, hypercholesterolemia and smoking were significantly associated with hypertension. The odds ratio for hypertension between rural and urban areas was 1.45 (p < 0.0001). The cardiovascular risk-rating score of rural elderly was statistically higher than that of urban elderly (p < 0.001). CONCLUSION: There were some minor differences in health status between urban and rural elderly. Health promotion should be varied according to the needs of various communities and various risk groups. Further studies should concentrate on prospective cohort research with well-defined determinants to evaluate whether cost-effective biopsychosocial intervention is necessary.

Aged↗
PubMed2001

[The combining ability and heterosis analysis of royal jelly yield and quality properties in western honeybees].

The NC II mating design of 2 x 4 was made in order to evaluate The combining ability and heterosis of royal jelly yield and quality properties that included royal jelly yield, royal jelly yield per cup, acceptance ratio and acidity in Apis mellifera. The results were as follows: (1) For all characters, general combining ability in six parents (GCA) achieved highly significant level (P < 0.01), special combining ability (SCA) only significant (P < 0.05), therefore the additive effect is more important for royal jelly yield and quality properties; (2) The GCA of A. m. acervorum in four characters was higher, and the SCA variance of A. m. carpatica, A. m. caucasica was greater, so they were good parents. ZND-1 Apis mellifera lingustica in royal jelly yield, royal jelly yield per cup, acceptance ratio was an excellent parent, but A. m. carnica only could be used in increasing royal jelly quality; (3) The heterosis over high-parent is negative, thus it is difficult to improve royal jelly yield and quality by cross breeding, but by appropriate choice of parents, high yield and quality combination can be obtained.

Animals↗
PubMed2001

Correlation of acoustic velocity of synovial fluid with markers of inflammation in arthritic patients.

Analysis of synovial fluid is important in the evaluation and treatment of arthritic conditions. This study measured the acoustic velocity of synovial fluids in patients with degenerative joint diseases, crystal arthropathy, and other inflammatory arthropathies using the ultrasonic pulse-echo method. The measured acoustic velocities of these bio-fluids were then correlated with clinical parameters including the synovial white blood cell count (WBC), clarity, viscosity, string test, erythrocyte sedimentation rate (ESR), and serum C-reactive protein (CRP). Results showed that the acoustic velocities were correlated with ESR (p = 0.0016) and CRP (p = 0.0001). The mean acoustic velocity of inflammatory synovial fluids, defined as synovial fluids with WBCs of more than 2000/mm3, was greater than that of synovial fluids with WBCs of less than 2000/mm3 (1550 +/- 4.5 m/s vs 1544 +/- 1.5 m/s, p = 0.007). This study demonstrated that the acoustic velocity of synovial fluid correlates well with severity of inflammation. These findings suggest that measurement of acoustic velocity may be useful in the clinical evaluation and management of arthritic conditions.

Arthritis↗
PubMed2001

Current studies on anti-endotoxic chemical components of traditional Chinese medicine in China.

Endotoxin (ET) was found to have wide bioactivities and ET antagonists have become the pop research topic in life science. The chemical components of traditional Chinese medicine (TCM) were the substance basis of its pharmacology. This review demonstrated the study state of about 18 chemical components from TCM, eg, organic acids of Radix Isatidis, anisodamine, matrine, tetramethypyrazine, colchicine, and glycine, etc, which showed anti-endotoxin effects through different routes. But now the most of them were limited to the laboratory. In the future, the trends of development should not only enlarge the range of research, but also strengthen the clinical study.

Alkaloids↗
PubMed2001

[Application of brain state related EEG complexity measure in mental workload evaluation].

Objective. The Application of Cs to mental workload evaluation was investigated. Method. EEG of 47 male (aged 23-33) were recorded during rest or doing mental arithmetic, and changes of Cs with relation to mental arithmetic load were analyzed and compared by means of Cs analysis method. Result. Cs distribution was laterally symmetry, higher in temporal and lower in occiput. The changes of Cs over some brain areas were outstanding and stable while doing mental arithmetic: type A, 38 subjects (81%), Cs under mental arithmetic were significantly higher than Cs under rest except over prefrontal, and the most outstanding areas were post-temporal and left parieto-occipital regions; type B, 9 subjects (19%), Cs over post-temporal and parieto-occipital under rest is higher than type A, and Cs under mental arithmetic descend significantly (the most outstanding areas were right central and mid-temporal, then left frontal-central and pre-temporal). Moreover there were some possible relationship among Cs, mental arithmetic score and subjective evaluation of mental workload. Conclusion. There exists high correlation between Cs and mental arithmetic activity, and Cs could well reflect brain function state. It provide a new method and a possible way for objective evaluation of mental workload and studies of brain cognitive activities.

Adult↗
PubMed2001

[Effect of head-down bed rest on human EEG].

Objective. To study the influences of short-term simulated weightlessness on human EEG. Method. EEG of 12 male subjects (aged 18-22) was recorded, pre-HDBR (-6 degrees head down bed rest), mid-HDBR (3rd, 4th, 6th day) and post-HDBR (3rd day). Then these EEG recordings were analyzed by power spectral analysis. Result. During HDBR, peak frequency of EEG gradually slowed down (6th day, P<0.05). Alpha-band activities were enhanced (alpha1: P<0.001. Alpha2: 3rd and 6th day, P<0.05; 4th day, P<0.001) and reached maximum on the 4th day. Alpha1/alpha2 ascended (6th day, C3 and C4: p<0.02; F4, P4, T3, T4, T5: P<0.05). Theta-band activities enhanced (P<0.001), and reached maximum on the 3rd day at frontal regions, on the 4th day at parieto-occipital regions. Theta/alpha ascended obviously (6th day, P3, O1: P<0.05). Meanwhile, beta1, activities also enhanced (P<0.001), and reached maximum on the 3rd day at frontal regions. After HDBR, the index that recovered to the pre-HDBR level first was EEG peak frequency. Conclusion. HDBR caused obvious changes of EEG power spectrum characteristic. There exists a potential influence on brain function.

Adolescent↗
PubMed2001

[A clinical trial of triclabendazole in the treatment of human paragonimiasis skrjabini].

OBJECTIVE: To observe the therapeutic effect of triclabendazole in patients with paragonimiasis skrjabini. METHODS: Four patients were treated with triclabendazole at dosage of 10 mg/kg bid for 3 days and were followed up for 6-10 months. The clinical symptoms, chest X-ray, hemogram and liver function tests were observed before and after treatment. RESULTS: Migratory subcutaneous nodules in three patients all disappeared. Small amount of pleural effusion were absorbed in two patients. Severe headache subsided in a patient with cerebral lesion. MRI showed a bean-sized calcified spot in the right frontal region. Chest X-ray in 2 patients showed that pulmonary lesions were markedly absorbed and disappeared. There was no adverse effect of the drug. CONCLUSION: Triclabendazole has marked therapeutic effect on paragonimiasis skrjabini. It is safe in administration and well tolerated.

Adolescent↗
PubMed2001

[Clinical observation on treatment of asthma in moderate degree with fluticasone inhalation combined with jinacon].

OBJECTIVE: To observe the efficacy of Fluticasone inhalation combined with Jinacon (JNC) orally taken in treating patients of chronic asthma (CA) of moderate degree. METHODS: Seventy-two CA patients were divided into three groups randomly and treated with Fluticasone inhalation combined with JNC, Fluticasone inhalation alone and JNC alone respectively for 4 weeks. The changes of clinical symptoms, airway reactivity and pulmonary function after treatment were observed. RESULTS: The clinical symptoms, pulmonary function and airway hyper-reactivity were improved in all the three groups after treatment (P < 0.05 or P < 0.01), but the improvement was more significant in the group treated with the combined therapy (P < 0.05 or P < 0.01). CONCLUSION: Fluticasone inhalation combined with JNC orally taken is an effective therapy in treating patients of chronic asthma of moderate degree.

Administration, Inhalation↗
PubMed2000

ADP is the cognate ligand for the orphan G protein-coupled receptor SP1999.

P2Y receptors are a class of G protein-coupled receptors activated primarily by ATP, UTP, and UDP. Five mammalian P2Y receptors have been cloned so far including P2Y1, P2Y2, P2Y4, P2Y6, and P2Y11. P2Y1, P2Y2, and P2Y6 couple to the activation of phospholipase C, whereas P2Y4 and P2Y11 couple to the activation of both phospholipase C and the adenylyl cyclase pathways. Additional ADP receptors linked to Galpha(i) have been described but have not yet been cloned. SP1999 is an orphan G protein-coupled receptor, which is highly expressed in brain, spinal cord, and blood platelets. In the present study, we demonstrate that SP1999 is a Galpha(i)-coupled receptor that is potently activated by ADP. In an effort to identify ligands for SP1999, fractionated rat spinal cord extracts were assayed for Ca(2+) mobilization activity against Chinese hamster ovary cells transiently transfected with SP1999 and chimeric Galpha subunits (Galpha(q/i)). A substance that selectively activated SP1999-transfected cells was identified and purified through a series of chromatographic steps. Mass spectral analysis of the purified material definitively identified it as ADP. ADP was subsequently shown to inhibit forskolin-stimulated adenylyl cyclase activity through selective activation of SP1999 with an EC(50) of 60 nM. Other nucleotides were able to activate SP1999 with a rank order of potency 2-MeS-ATP = 2-MeS-ADP > ADP = adenosine 5'-O-2-(thio)diphosphate > 2-Cl-ATP > adenosine 5'-O-(thiotriphosphate). Thus, SP1999 is a novel, Galpha(i)-linked receptor for ADP.

3T3 Cells↗
PubMed2000

BPV1 E2 protein enhances packaging of full-length plasmid DNA in BPV1 pseudovirions.

We studied determinants of efficient encapsidation of circular DNA, incorporating a PV early region DNA sequence (nt 584-1978) previously shown to enhance packaging of DNA within papillomavirus (PV)-like particles (VLPs). Insect coelomic cells (Sf-9) and cultured monkey kidney cells (Cos-1) were transfected with an 8-kb reporter plasmid incorporating the putative BPV packaging sequence and infected with BPV1 L1 and L2 recombinant baculovirus or vaccinia virus. Heavy (1.34 g/ml) and light (1.30 g/ml) VLPs were produced, and each packaged some of the input plasmid. In light VLPs, truncated plasmids, which nevertheless incorporated the PV-derived DNA packaging sequence, were more common than full-length plasmids. Packaging efficiency of the plasmid was estimated at 1 plasmid per 10(4) VLPs in both Cos-1 and Sf-9 cells. In each cell type, expression of the BPV1 early region protein E2 in trans doubled the quantity of heavy but not light VLPs and also increased the packaging efficiency of full-length circular plasmids by threefold in heavy VLPs. The resultant pseudovirions incorporated significant amounts of E2 protein. Pseudovirions, comprising plasmids packaged within heavy VLPs, mediated the delivery of packaged plasmid into Cos-1 cells, whereby "infectivity" was blocked by antisera to BPV1 L1, but not antisera to BPV1 E4. We conclude that (a) packaging of DNA within PV L1+L2 pseudovirions is enhanced by BPV1 E2 acting in trans, (b) E2 may be packaged with the pseudovirion, and (c) E2-mediated enhancement of packaging favors 8-kb plasmid incorporation over incorporation of shorter DNA sequences.

Animals↗
PubMed2000

[Effects on simvastatin in continuous ambulatory peritoneal dialysis patients with hyperlipidemia].

The therapeutic effects of simvastatin on hyperlipidemia and its protective effects on residual renal function (RRF) in continuous ambulatory peritoneal dialysis (CAPD) patients with hyperlipidemia were observed. Forty-seven CAPD patients were randomly divided into two groups, the treatment group and control group. The treatments of two groups were the same except that the treatment group patients were additionally given simvastatin 20 mg.d-1. The results were that, after 12-week treatment, the total cholesterol (TC), triglyceride (TG), low density lipoprotein (LDL), and apoprotein B100 (ApoB100) in the treatment group significantly decreased, but high density lipoprotein (HDL) and apoprotein A1 (ApoA1) significantly increased compared with the control group (all P < 0.05); one year later, RRF of patients of both groups all decreased but there was no significant difference between them. The results suggest that simvastatin can effectively normalize lipidemia, but has no protective effect on RRF in CAPD patients.

Adult↗