Biomedical subjects

G Yu

Publications and source records attributed to G Yu.

At least 163 records · Page 9Linked to original sources

PubMed1998

Analysis of the butyrylcholinesterase gene and nearby chromosome 3 markers in Alzheimer disease.

The K-variant of butyrylcholinesterase (BCHE-K) recently has been reported to be associated with Alzheimer disease (AD) in carriers of the epsilon4 allele of the apolipoprotein E (APOE) gene. We have re-examined the frequency of the BCHE-K allele in a large data set of both sporadic and familial cases of AD disease, and we have also examined the segregation of three genetic markers on chromosome 3 near BCHE . Our data neither support an association of BCHE-K with sporadic or familial AD, nor do they suggest the existence of another gene nearby on chromosome 3 as a common cause of familial AD.

Aged↗

PubMed1998

Polyunsaturated fatty acids in school children in relation to allergy and serum IgE levels.

Altered composition of polyunsaturated fatty acids (PUFA) has been observed in allergic individuals and it has been proposed that this is due to an impairment of delta-6-desaturase activity. We have studied the composition of PUFA in serum phospholipids in twenty-two 12-15 year old children with asthma and/or allergic dermatitis and 23 non-atopic controls of similar age. The relative levels of docosahexaenoic acid (DHA, C22:6n-3) and total n-3 long-chain polyunsaturated fatty acids (LCP) were lower (1.46% +/- 0.54 vs. 1.90% +/- 0.58, P = 0.01 for DHA and 2.34% +/- 0.67 vs. 2.80% +/- 0.77, P < 0.05 for total n-3 LCP) and the ratio of total n-6 to n-3 LCP was higher (P < 0.01) in the allergic children than in the controls. In addition to these differences, the relative levels of docosapentaenoic acid (DPA, C22:5n-3) and the ratio of arachidonic acid (AA, C20:4n-6) to dihomo-gamma-linolenic acid (DHGLA, C20:3n-6) were also lower in the 12 allergic children with positive skin prick test, as compared with the SPT negative children (both P < 0.05). In non-allergic children, the levels of total n-3 correlated with n-6 LCP (r = 0.76, p < 0.001). Furthermore, the n-3 LCP, i.e. EPA, DPA and DHA, correlated significantly with each other (r = 0.52-0.78, all p < 0.01) and correlated with n-6 LCP, i.e. C20:2, DHGLA and AA respectively (r = 0.56-0.83, all P < 0.01). Most of these correlations were absent in allergic children. Higher levels of C20:2n-6 and lower levels of eicosapentaenoic acid (EPA, C20:5n-3) were recorded in 11 allergic children with serum IgE above the median level (56 kU/l), as compared to 11 with lower IgE levels (both P < 0.05). Furthermore, the levels of C20:2n-6 correlated with the IgE levels in the children (r = 0.65, P = 0.001). The findings could not confirm an impaired delta-6-desaturase activity in allergic school children and suggest that a disturbance of LCP metabolism is associated with allergic diseases.

Adolescent↗

PubMed1998

Atopic sensitization during the first year of life in relation to long chain polyunsaturated fatty acid levels in human milk.

The levels of the long chain polyunsaturated n-6 and n-3 fatty acids (PUFA) were studied in colostrum and mature milk of 29 atopic and 29 nonatopic mothers and related to sensitization in their babies during the first 12 mo of life. The levels of alpha-linolenic acid (LNA) were lower (0.96 versus 1.23 weight percentage, p < 0.01) and the levels of dihomo-gamma-linoleic acid were higher (0.36 versus 0.31 weight percentage, p < 0.05) in mature milk from mothers of atopic babies (n = 24) compared with mothers of nonatopic babies (n = 34). The total n-3 levels and the ratio of n-6 PUFA/n-3 PUFA were similar in colostrum of all mothers and then decreased significantly in mature milk (p < 0.001), particularly in milk given to atopic babies. The levels of the n-6 fatty acids arachidonic acid, C22:4, and C22:5 n-6 correlated in milk samples from nonatopic mothers (r = 0.61-0.97, p < 0.05 to p < 0.001) but were largely absent in colostrum and mature milk from atopic mothers. In contrast, LNA and eicosapentaenoic levels correlated in colostrum from the atopic mothers (r = 0.61-0.88) regardless of atopic sensitization in the infants, whereas LNA correlated to C20:4 n-3 in colostrum from nonatopic mothers of nonatopic infants. Furthermore, the levels of the n-3 fatty acid C20:4 n-3 correlated significantly to all n-6 fatty acids, except linoleic acid (r = 0.64-0.79, all p < 0.01) in mature milk from nonatopic mothers of nonsensitized children. Low levels of LNA and total n-3 long chain polyunsaturated fatty acids, in mature milk from the mothers, appear to be associated with atopic sensitization early in life, as well as disturbed relationships between the n-3 fatty acid 20:4 and the n-6 fatty acids particularly in mature milk. On the other hand, disturbed relationships within the individual fatty acids in the n-6 series in human milk reflected the atopic status in the mothers. The variations in the lipid composition of human milk could in part explain some of the controversies regarding the protective effects of breast-feeding against allergy.

Arachidonic Acids↗

PubMed1998

Antioxidative activity of carp blood plasma on lipid peroxidation.

Antioxidative activity of carp blood plasma was estimated by measuring hydroperoxides formed by liposome peroxidation during the exposure of liposomes to AAPH. Ascorbic acid of high concentration, uric acid of low content, and tocopherol formed special protective system against lipid poroxidation in fish plasma. The decrease of uric acid, ascorbic acid, and tocopherol showed synergism of ascorbic acid and tocopherol, uric acid, and tocopherol. Carp blood plasma with a low concentration of protein (about 2%) and SH groups (88 microM) had a great effect on the antioxidative activity, as the effects of ascorbic acid, uric acid, and tocopherol were dramatically extended. Dialysed carp protein also displayed a very strong antioxidative activity on lipid peroxidation of a multilayer liposome system.

Adult↗

PubMed1998

Antioxidative activities of several marine polysaccharides evaluated in a phosphatidylcholine-liposomal suspension and organic solvents.

The antioxidative activities of several water-soluble marine polysaccharides, alginate (ALG), alginate sulfate (SALG), propylene glucolalginate sodium sulfate (PSS), propylene glucol mannuronate sulfate (PGMS), the oligosaccharide of chitosan (OLC), N,O-carboxymethyl chitosan (NOCC) and hydroxypropylated chitosan (HPC), were examined in a phosphatidylcholine (PC)-liposomal suspension containing the water-soluble radical emitter, 2,2'-azobis (2-amidinopropane) dihydrochloride. In the suspensions containing OLC and SALG, the initial rates of PC-OOH accumulation were 2.78 x 10(-8) MS-1 and 2.88 x 10(-8) MS-1, respectively, while all the polysaccharides tested showed antioxidative activity. Liposoluble marine polysaccharides, hexanoyl chitin (HCH) and an N-benzoylhexanoyl chitosan (NBHC) solution, also retarded the hydroperoxide accumulation of methyl linoleate by effectively trapping peroxide radicals in organic solvents when the radical chain reaction had been initiated by 2,2'-azobis (2,4-dimethylvaleronitrile). The kinetic data presented indicate that the alginate and chitin derivatives can be expected to play a role in the antioxidative mechanism of biological systems.

Alginates↗

PubMed1998

[Microsurgical treatment of ischemic necrosis of the head of the 2nd metatarsal bone].

In order to explore a new method to treat the ischemic necrosis of the head of 2nd metatarsal bone in adult, transposition of reversed vascularized metatarsal bone graft was adopted in the treatment of 4 cases, 2 of which were followed up for one and a half years. The postoperative X-ray showed the round head of the 2nd metatarsal bone became round and even density. The clinical observation showed that there was excellent function of metatarsophalangeal joint. It was concluded that the reversed vascularized metatarsal bone graft could provide a reliable blood supply and various osteogenic factors to the avascularized head of the metatarsal bone, and the operation could also debride the joint cavity and carry out decompression.

Adult↗

PubMed1998

[Comparative study of left ventricular morphology and function of patients with left ventricular systolic and diastolic heart failure on echocardiography].

Left ventricular pathology and pathophysiological characteristics of fifty patients with left ventricular diastolic heart failure (LVDHF), and 35 patients with left ventricular systolic heart failure (LVSHF) diagnosed by clinical manifestations and radionuclide ventriculography, were examined by echocardiography and 20 healthy persons were served as control group. Left atrial diameter (LAD), interventricular septum thickness (IVST) and posterior wall thickness (PWT) and left ventricular mass index (LVMI) were significantly increased in the patients with LVDHF, while left ventricular diameter (LVD) was significantly increased in the patients with LVSHF. Left ventricular ejection fraction (LVEF), cardiac index (CI) were significantly decreased in the patients with LVSHF. Early peak filling velocity (EPFV), atiral peak filling velocity (APFV), deceleration of early peak filling velocity (DC) and isovolumic relaxation time (IRT) in the patients with LVDHF and LVSHF observed no significant difference.

Adult↗

PubMed1998

[Clinical study on left ventricular diastolic heart failure in the aged patients].

Forty aged patients with LVDHF and 30 with left ventricular systolic heart failure (LVSHF), confirmed by radionuclide ventriculography were studied by clinical, echocardiography and treadmill test. Twenty healthy aged persons were served as control group. Compared with LVSHF, short duration and less severe manifestations of heart failure in LVDHF were observed. Compared with the control, left atrium was enlarged but not the left ventricular chamber, and LV wall was thickened in LVDHF, while enlargement of LV chamber was only found in LVSHF. However, LV systolic function was remained normal in LVDHF. The exercise tolerance was decreased in both LVDHF and LVSHF groups, but more marked in LVSHF.

Aged↗

PubMed1998

[Effects of low concentration ozone on the respiratory system of mice].

Effects of low concentration of O3 on the respiratory system in mice were studied in the present study. Mice were exposed to 0.1, 0.25 and 1.0 mg/m3 of O3, respectively for 8 h per day for 3 days. Cilia in brochia, Lipid peroxide (LPO) in lung tissue and phagocytic function of macrophage in mice were examined. The results showed that there were cilia damage in the 1.0 mg/m3 group and swelling of mitochondrias as well as endoplasmic reticulums in the 0.25 mg/m3 group. But no damage was found in the group of 0.1 mg/m3. Furthermore, phagocytic rates in the 0.25 and 1.0 mg/m3 groups were significantly lower than that of control group (P < 0.01). No differences in LPO leads were found.

Animals↗

PubMed1998

[Observation of enalapril on treating the patients with left ventricular diastolic dysfunction].

The effects of enalapril on 50 patients with left ventricular diastolic dysfunction (LVDD), confirmed by clinical features and radionuclid ventriculography, were assessed in a randomized, double-blind, and controlled method for eight weeks. The results showed that left atrial diameters (LAD), interventricular septum thicknesses (IVST) and left ventricular mass indexes (LV-MI) except left ventricular diameters (LVD) were decreased in the enalapril treatment group. The left ventricular diastolic function parameters such as the early peak filling velocity (EPAV), the atrial peak filling velocity (APAV), the deceleration of early peak filling velocity (DC) and the isovolumic relaxation time (IRT) were improved, the NYHA class and the exercise tolerance were increased, the left ventricular ejection fraction (LVEF), and the cardiac index (CI) were not altered in the enalapril treatment group. The patients with LVDD were well tolerated with enalapril. The parameters mentioned above were not altered in control group. It is suggested that enalapril is an effective drug in the treatment of LVDD.

Adult↗

PubMed1998

[Effects of oxidatively modified lipoproteins on the expression of monocyte chemoattractant protein-1 in endothelial cells].

OBJECTIVE: To clarify whether lipoproteins, particularly oxidatively modified low density lipoprotein (OX-LDL) and very low density lipoprotein (OX-VLDL) play a role in the express of monocyte chemoattractant protein-1 (MCP-1) mRNA and protein in endothelial cells (ECs). METHODS: After a 24-hour exposure to LDL, OX-LDL, VLDL and OX-VLDL respectively the total RNA in call aorta ECs was extracted by means of guanidinium isothiocyanate method. MCP-1 mRNA expression in ECs was examined by dot blot analysis using a gamma-32P-end-labelled 35 mer oligonucleotide probe of MCP-1. Meanwhile, MCP-1 protein in EC conditioned media (EC-CM) of each group was determined by sandwich ELISA, and MCP-1 protein in ECs was examined immunocytochemically as well. RESULTS: Cultured calf aorta ECs expressed MCP-1 mRNA and protein, and OX-LDL and OX-VLDL induced further a strong expression of MCP-1 mRNA, and an increased MCP-1 protein level in EC-CM. The expression of MCP-1 mRNA and protein was only slightly increased when exposed to LDL and VLDL, and immunohistological staining with polyclonal MCP-1 antibody give a similar result. CONCLUSION: OX-LDL and OX-VLDL are able to induce a strong expression of MCP-1 in ECs.

Animals↗

PubMed1998

[Nasal neuroendocrine carcinoma].

OBJECTIVE: To recognize and understand further nasal neuroendocrine carcinoma (NNC), improve the diagnosis and therapeutic effect. METHODS: Eight cases of the nasal neuroendocrine carcinomas (7 males, 1 female) were analyzed. Among them, 6 cases had tumors in left side of nose, 2 in right side. The average course was only 2.8 months, but the lesions were often extent. RESULTS: The patients were pathologically confirmed to be neuroendocrine carcinomas. 5 cases were of small cell type, 2 undifferentiated, 1 poorly differentiated. One patient died 14 months after treatment. 2 cases were lost for follow-up. The others were still in treatment. CONCLUSION: The nasal neuroendocrine carcinoma has rapid progress and poor prognosis. Clinically, combined treatment should be adopted, the effect of simple operation was poor.

Adolescent↗

PubMed1998

[A study of epithelial cell kinetics of the odontogenic keratocyst].

OBJECTIVE: To study epithelial cell kinetics of the odontogenic keratocyst. METHODS: Proliferating cell nuclear antigen (PCNA) immunohistochemistry in 60 cases and cellular nuclear DNA contents cytometry in 40 cases were used to compare the epithelial cell kinetics of the odontogenic keratocyst, radicular cyst, dentigerous cyst, and ameloblastoma. RESULTS: The epithelial cells in odontogenic keratocyst has the potential of active growth instead of passive expanding. CONCLUSION: The authors suggest that the odontogenic keratocyst should be termed as "odontogenic keratocystic tumor" because is aggressive growth potential.

Cell Division↗

PubMed1998

[Recovery of submandibular gland function following transoral sialolithectomy].

OBJECTIVE: Investigate the recovery of the submandibular gland function following transoral sialolithectomy. METHODS: The glandular function of 26 patients who received the transoral sialolithectomy were investigated by sequential scintigraphy with 99m Tc pertechetate. RESULTS: Most glandular function recovers normal in short time after operation. Glandular infection, calculus diameter and patients's age could influence the recovery of function. CONCLUSION: In the treatment of sialolithiasis, breaking up the pathogenic process of calculus formation and effectively controlling the glandular infection are very important in preventing from the function reduction. After transoral sialolithectomy preserving the anatomical normal orifice of the duct, and using silivators may be very favorable for the function recovery.

Adolescent↗

PubMed1998

In vivo native cellular fluorescence and histological characteristics of head and neck cancer.

Native cellular fluorescence (NCF) represents the innate capacity of tissues to absorb and emit light of a specified wavelength. The ability to define the relationship of in vivo NCF with biological characteristics of neoplastic disease may allow for an improved understanding of the clinical course of disease. Head and neck cancers from 35 patients were evaluated in vivo for NCF characteristics using a xenon lamp-based spectrometer coupled to a handheld fiberoptic probe. Spectral assessment was limited to lambda 450-nm emission characteristics, in which tissues were excited at various wavelengths, ranging from lambda 290 nm to lambda 415 nm, and the intensity of lambda 450 nm emission was recorded. Each cancer was subsequently biopsied and assessed for histological differentiation by a pathologist who was blinded to NCF analysis. Considerable variation in spectral characteristics between head and neck cancers was identified, which was determined, in part, by NCF characteristics of the normal mucosa from the same patient. Poorly differentiated tumors were more likely than well- or moderately differentiated tumors to have lower excitation maxima (P < 0.05 by ANOVA). Most significantly, the tumor differentiation status, as well as the probability of demonstrating recurrent disease, could also be related to the NCF characteristics of the patient's normal mucosa from the same site within the upper aerodigestive tract. NCF analysis may represent an effective tool to identify biological characteristics of head and neck tumors in vivo without the need for invasive biopsies. Results suggest the need to explore the determinants of NCF characteristics expressed by clinically normal mucosa.

Adult↗

PubMed1998

Orthogeriatric rehabilitation: which patients benefit most?

Liaison between orthopaedic surgeons and geriatricians offers significant advantages to the increasing numbers of elderly patients sustaining hip fractures. This article discusses who can benefit most from such orthogeriatric rehabilitation.

Aged↗

PubMed1997

An antagonist decoy receptor and a death domain-containing receptor for TRAIL.

TRAIL, also called Apo2L, is a cytotoxic protein that induces apoptosis of many transformed cell lines but not of normal tissues, even though its death domain-containing receptor, DR4, is expressed on both cell types. An antagonist decoy receptor (designated as TRID for TRAIL receptor without an intracellular domain) that may explain the resistant phenotype of normal tissues was identified. TRID is a distinct gene product with an extracellular TRAIL-binding domain and a transmembrane domain but no intracellular signaling domain. TRID transcripts were detected in many normal human tissues but not in most cancer cell lines examined. Ectopic expression of TRID protected mammalian cells from TRAIL-induced apoptosis, which is consistent with a protective role. Another death domain-containing receptor for TRAIL (designated as death receptor-5), which preferentially engaged a FLICE (caspase-8)-related death protease, was also identified.

Amino Acid Sequence↗

PubMed1997

Antitumor activity of the novel human breast cancer growth inhibitor, mammary-derived growth inhibitor-related gene, MRG.

A novel human tumor growth inhibitor was identified by differential cDNA sequencing. The predicted amino acid sequence of this tumor-suppressing factor has a significant sequence homology to mouse mammary-derived growth inhibitor and thus was named mammary-derived growth inhibitor-related gene (MRG). MRG was found to be expressed in normal and benign human breast tissues but not in breast carcinomas. In situ hybridization analysis demonstrated a stage-specific MRG expression as follows. MRG was barely detectable in breast carcinomas, showed partial and weak expression in benign hyperplasia, but was expressed at a high level in normal breast epithelial cells. To determine if MRG can modulate in vivo growth of human breast cancers, we transfected a full-length MRG cDNA into MDA-MB-231 human breast cancer cells and studied the orthotopic growth of MRG transfectants versus control transfectants in the mammary fat pad of athymic nude mice. Overexpression of MRG in human breast cancer cells significantly suppressed cell proliferation in vitro and tumor growth in an orthotopic nude mouse model. These results suggest that MRG has tumor-suppressing activity, and the loss of MRG expression may be involved in the development and progression of breast cancer.

Amino Acid Sequence↗