PubMed Health⌕ Search

Biomedical subjects

G Yu

Publications and source records attributed to G Yu.

At least 127 records · Page 7Linked to original sources
PubMed1999

Presenilins interact with armadillo proteins including neural-specific plakophilin-related protein and beta-catenin.

Missense substitutions in the presenilin 1 (PS1) and presenilin 2 (PS2) proteins are associated with early-onset familial Alzheimer's disease. We have used yeast-two-hybrid and coimmunoprecipitation methods to show that the large cytoplasmic loop domains of PS1 and PS2 interact specifically with three members of the armadillo protein family, including beta-catenin, p0071, and a novel neuronal-specific armadillo protein--neural plakophilin-related armadillo protein (NPRAP). The PS1:NPRAP interaction occurs between the arm repeats of NPRAP and residues 372-399 at the C-terminal end of the large cytoplasmic loop of PS1. The latter residues contain a single arm-like domain and are highly conserved in the presenilins, suggesting that they form a functional armadillo protein binding site for the presenilins.

Alzheimer Disease↗
PubMed1999

Parent management training in a Chinese population: application and outcome.

OBJECTIVE: To examine the applicability and outcome of parent management training in a group of Chinese children referred for aggressive and defiant behaviors. METHOD: Twenty-five children (aged 4-10 years) were assigned to a standardized 8 to 12 sessions of parent management training. Trained child and adolescent psychiatric nurses conducted the treatment. Measures taken at pretreatment, posttreatment, and 4-month follow-up period included the Child Behavior Checklist, direct observation of parent-child interactions, and a parent perception inventory. RESULTS: Significant therapeutic gains occurred in parent-child interactions, externalizing behaviors, and parents' perception of their parenting behaviors. These were maintained at 4-month follow-up. Fifty-two percent of cases improved to a level below clinical cutoffs. Poor parent-child interactions had stronger correlation with externalizing disturbances than internalizing disturbances. The changes in parent-child interactions had low correlation with the changes in the symptom profiles. CONCLUSIONS: The data provide preliminary evidence for the efficacy of parent management training for Chinese children with conduct problems. The rationale for its success and modifications to improve its cultural sensitivity are discussed.

Adult↗
PubMed1999

Loperamide (ADL 2-1294), an opioid antihyperalgesic agent with peripheral selectivity.

The antihyperalgesic properties of the opiate antidiarrheal agent loperamide (ADL 2-1294) were investigated in a variety of inflammatory pain models in rodents. Loperamide exhibited potent affinity and selectivity for the cloned micro (Ki = 3 nM) compared with the delta (Ki = 48 nM) and kappa (Ki = 1156 nM) human opioid receptors. Loperamide potently stimulated [35S]guanosine-5'-O-(3-thio)triphosphate binding (EC50 = 56 nM), and inhibited forskolin-stimulated cAMP accumulation (IC50 = 25 nM) in Chinese hamster ovary cells transfected with the human mu opioid receptor. The injection of 0.3 mg of loperamide into the intra-articular space of the inflamed rat knee joint resulted in potent antinociception to knee compression that was antagonized by naloxone, whereas injection into the contralateral knee joint or via the i.m. route failed to inhibit compression-induced changes in blood pressure. Loperamide potently inhibited late-phase formalin-induced flinching after intrapaw injection (A50 = 6 microgram) but was ineffective against early-phase flinching or after injection into the paw contralateral to the formalin-treated paw. Local injection of loperamide also produced antinociception against Freund's adjuvant- (ED50 = 21 microgram) or tape stripping- (ED50 = 71 microgram) induced hyperalgesia as demonstrated by increased paw pressure thresholds in the inflamed paw. In all animal models examined, the potency of loperamide after local administration was comparable to or better than that of morphine. Loperamide has potential therapeutic use as a peripherally selective opiate antihyperalgesic agent that lacks many of the side effects generally associated with administration of centrally acting opiates.

Analgesics, Opioid↗
PubMed1999

Therapeutic efficacy of transcatheter arterial embolization of primary hepatocellular carcinoma: discrepancy in different histopathologic subtypes.

OBJECTIVE: To evaluate preliminarily the therapeutic efficacy of transcatheter arterial embolization (TAE) for different histopathologic subtypes of primary hepatocellular carcinoma (HCC). METHODS: A retrospective study of 226 patients with histopathologically diagnosed primary HCC was performed. The patients were treated with either single TAE, surgical resection of tumor alone, or TAE combined with surgical resection. Follow-up information was achieved in 157 of 226 patients. Comparative analyses of survival data and image findings were performed with correlation to histopathologic classification and different therapeutic methods, respectively. RESULTS: Eight histopathologic subtypes of primary HCC were found in this group, including HCC of trabecular pattern, pseudoglandular pattern, fibrolamellar HCC and sclerosing HCC, as well as HCC of clear cell, of small cell, poorly differentiated or undifferentiated HCC, and hormonally active HCC. The accumulated survival rate for these 157 patients was 74.52% of 1 year, 53.50% of 2 years, 31.85% and 14.01% of 3 and 5 years, respectively. Fibrolamellar HCC and clear cell HCC had relatively higher survival rate (25.00% and 33.22% of 5 years, respectively) than that of other subtypes, and the median survival time of the latter was 71 months. The mean survival time was 25.06 months (SE = 1.87) in single TAE group, 30.38 (SE = 2.05) months in surgical resection, and 72 months (SE = 6.90) in TAE combined with resection. CONCLUSIONS: Discrepancies do exist in therapeutic effect of different subtypes of HCC. In this study, clear cell HCC was more sensitive to TAE than other subtypes, and, in contrast, small cell HCC and poorly differentiated or undifferentiated HCC were of lower sensitivity to TAE.

Carcinoma, Hepatocellular↗
PubMed1999

[The effects of L-arginine and nimodipine on the expression of monocyte chemoattractant protein-1 in endothelial cells induced by lipopolysaccharide].

OBJECTIVE: To examine the effects of L-arginine and nimodipine on the expression of monocyte chemoattractant protein-1 (MCP-1) mRNA and protein induced by lipopolysaccharide (LPS) in endothelial cells (ECs). METHODS: After 8-hour exposure to LPS, LPS + L-arginine and LPS + nimodipine respectively, the total RNA in ECs was extracted by the guanidinium isothiocyanate method. The MCP-1 mRNA expression in ECs was examined by Dot blot analysis using a gamma-32P-end-labeled 35 mer oligonucleotide probe of MCP-1. MCP-1 protein in the EC-conditioned media (EC-CM) was determined by sandwich ELISA for each group. The expression of MCP-1 protein in ECs was examined immunocytochemically. RESULTS: Dot blotting showed that after exposure to LPS, the integral absorbance (A) value of the dots of MCP-1 mRNA on the nitrocellulose membrane were 3.14, which was 2.5-fold as much as that in the control group (A = 1.24). The A values of the LPS + L-arginine group and the LPS + nimodipine group were 1.43 and 1.65, respectively. ELISA showed that the MCP-1 protein content in the EC-CM of the LPS group was 6.29 +/- 0.53 ng/ml, which was markedly higher than that of the control group (2.32 +/- 0.16) ng/ml (P < 0.01). The MCP-1 protein content in the EC-CM of the LPS + L-arginine group and the LPS + nimodipine group was significantly lower than that of the LPS group (P < 0.01). Furthermore, the ECs in LPS group showed a strong immunoreactivity for the polyclonal MCP-1 antibody, whereas the ECs in control, L-arginine and nimodipine groups revealed a weak postive immunostaining. CONCLUSION: L-arginine and nimodipine can markedly inhibit the expression of MCP-1 in ECs induced by LPS.

Animals↗
PubMed1999

[Imaging findings of fibrolamellar hepatocellular carcinoma].

OBJECTIVE: To describe the imaging findings of fibrolamellar hepatocellular carcinoma(FL-HCC). METHODS: Imaging studies in 11 patients with pathologically confimed F1-HCC were reviewed. There was no cirrhosis or hepatitis according to patients' history. Serum alpha-fetoprotein level was normal in all patients. Imaging studies included ultrasonography(US) in 10 patients, CT in 11, MRI in 8, and angiography in 9. RESULTS: (1) On US, the echogenicity of the tumor was hyperechoic relative to normal liver in four patients, and mixed in six. Cyst-like regions with various sizes were found within the masses in four patients, Doppler US revealed that the solid portion of the tumor was hypervascullar. (2) Nonenhanced CT scan demonstrated a well demarcated, solitary mass in 9 patients, and a multilobulated mass in 2. All masses were non-homogeneous and hypodense to the liver. Seven of the lesions had a central lower density region with radiating pattern which was confirmed as densely packed scar by pathologic examination. Punctate calcification was seen in 4 of 11 patients. Marked contrast enhancement of the masses was seen on the arterial dominated phase in 7 patients under enhanced CT, and a central nonenhanceing scar-like structure was found in 4 of the seven patients, Liver cirrhosis and splenomegaly were not found in this series. (3) On MRI, the tumor was hypointense relative to the liver parenchyma on T1-weighted spin-echo image and non-homogeneous hyperintense on T2-weighted image. Six of the eight patients had a central radiate-like structures which were hypointense on both T1 and T2-weighted images. On contrast enhanced MRI, four of five patients had obvious enhancement, and the central scar did not enhance on both early and delayed enhancement. (4) On angiography, a globular hypervascular mass with neovascularity was found in four of the nine patients. Peripheral nodular tumor stain, which was similar to that of hemangioma, was seen in 3 patients. A hypovascular mass with displacement of the adjacent vessels was found in 2 cases. No tumor thrombus in the portal vein, nor arterial shunting to the portal vein was identified. CONCLUSION: Typical imaging features in young patients of a large hepatic mass with central scar and calcification but without cirrhosis might be suggestive of FL-HCC.

Adolescent↗
PubMed1999

[Basal cell adenocarcinoma of the salivary gland: a clinicopathologic study of 14 cases].

OBJECTIVE: To study clinicopathologic features and behaviour of the basal cell adenocarcinoma of salivary gland tumor and prognosis of the patients, METHODS: 14 cases with basal cell adenocarcinoma were studied clinicopathologically. RESULTS: The clinical features were as follows: females more than males; most frequently in the minor salivary glands; 21.4% of cervical lymph node metastasis and 14.3% of distant metastasis; and rather poor prognosis. The histopathologic appearances were similar to those of basal cell adenoma, but with more mitotic figures and infiltrating growth. CONCLUSION: This tumor was of moderate grade malignancy. It must be treated radically. The elective neck dissection could be considered for the patients with extensive tumors.

Adenocarcinoma↗
PubMed1999

[The ultrastructure of membrane component in adenoid cystic carcinoma of salivary gland].

OBJECTIVE: To study morphological variations of basment membrane component (BMC) for determination of invasion and vascular metastasis in adenoid cystic carcinoma (ACC). METHODS: The BMC of 8 cases in ACC and 2 cases of normal parotid gland were observed by LM and EM. RESULTS: The BMC surrounding tumor mass and strands showed multi-layered or dissolution, pseudopodia were seen extended from tumor cells, and contained numerous microvesicles. If the tumor cell attached blood vessels, the collagenous fibril were dissoluted and BMC were lost. CONCLUSION: The tumor cell may release some digestive enzymes which may be able to dissolve BMC and collagenous fibrils and invade into blood vessels and metastasis take place.

Basement Membrane↗
PubMed1999

[Long-term complications associated with immediate plate reconstruction for mandibular defect following tumor-surgery].

OBJECTIVE: To assess the long-term complications associated with the application of reconstruction plate. METHODS: Ninety-seven patients underwent immediate repair by using bendable reconstruction plate for maintainance of space and contour following mandibular segmental resection. Of them, 68 cases were followed up for the final outcomes. RESULTS: Skin or mucosa perforation occurred 6 cases, instabilization of screws in 22 cases, and broken of plate in 3 cases. The reasons for skin or mucosa perforation was possibly associated with circulatory disturbance due to postoperative irradiation. The bone absorption and screw loosening occured most frequently in bone defect involving mandibular angle and chin. CONCLUSION: High concentration of unrationable stress and irradiation were recognised to be the factors responsible for the perforation of covering tissue and screw loosening. The broken of plate was brought about possibly by stress loading and fatigue weakness of plates.

Bone Plates↗
PubMed1999

[Age changes in CT values of human major salivary glands].

OBJECTIVE: To investigate CT values ranges of normal major salivary gland in different age groups and regularity of age changes. METHODS: CT values of normal parotid and submandibular glands, comparing with those of masseter and sterocleidomastoid muscles, were measured and analyzed in 100 cases with 4 different age groups. RESULTS: CT values of parotid and submandibular gland decreased with aging, whereas no significant age change in CT values occurred in the masseter and sterocleidomastoid muscles. The CT values of parotid and submandibular gland showed big differences in different age groups. This difference, however, became smaller after the case were divided in 4 groups reference to age. CONCLUSION: CT value ranges of normal major salivary gland should be determined according to the age. It is possible to take the contralateral gland as the control gland for CT diagnosis.

Adolescent↗
PubMed1999

[Evaluation of normal submandibular gland function by sialo-scintigraphy].

OBJECTIVE: To study the normal glandular function of the submandibular gland as a background for evaluation of changes in submandibular gland diseases. METHODS: The backgrounds of both submandibular area and temporal area were analyzed comparatively with Emission Computerized Tomography in eleven pairs of normal submandibular gland. RESULTS: About 2.18 times of the temporal background equals to submandibular area background; the Concentrate Index of normal submandibular gland was 1.42 +/- 0.89; the Secretory Index was (109.4 +/- 39.8)%, the Secretory Index Ratio and the Concentrate Index Ratio were (77.2 +/- 17.2)% and 71.0 +/- 15.2% respectively; and the Function Index was (89.9 +/- 7.4)%. CONCLUSION: The use of submandibular area background and functional index to represent submandibular gland function is more accurate and more sensitive. Normal functional index can provide the basis for researching submandibular gland disease.

Humans↗
PubMed1999

[Clinical practice of spherical allogeneic biological membranous implant in the eye socket].

OBJECTIVE: To investigate the effect of implantation of spherical allogeneic biological material implant after eyeball enucleation. METHODS: A spherical allogeneic biological material implant was implanted in the eye socket after eyeball enucleation in 50 cases including stage I in 48 cases and stage II in 2 cases. RESULTS: After operation, the motility of installed artificial eyes was good in 49 cases, the orbit and eyelids were full in all the cases. In the follow-up of 4 - 24 months (mean, 8 months), the conjunctival wound and muscular tissue were adherent firmly to the biological material, and there were no postoperative infection, no dislocation and shift of the implant. CONCLUSION: The spherical allogeneic biological membranous implant is an ideal material for the implantation in the eye socket after enucleation.

Adolescent↗
PubMed1999

[Expression of bcl-2, bax and p53 protein in the basal cell carcinoma].

The expression of bcl-2, bax and p53 protein was studied in the basal cell carcinoma with 32 patients by immunohistochemical method. The results showed that bcl-2 protein was positive in 26 patients (81.2%), bax protein was positive in 9 patients(28.1%), and p53 protein was positive in 13 patients (40.6%); there is a negative correlation between the expression of bcl-2 and bax protein(P < 0.05). These findings suggest that apoptosis is suppressed which might cause the production of basal cell carcinoma.

Aged↗
PubMed1999

[Effect of cadmium on the beta-adrenoreceptor of splenic cell of rats and its immunotoxicity].

Rats were given cadmium(Cd) alone or Cd with beta-antagonist in order to study the effect of Cd on beta-adrenoreceptor density of rat splenic cells. The subsets of T-lymphocytes (CD4+, CD8+, CD4+/CD8+) and the proliferation of T lymphocytes were also detected. Cadmium alone stimulated and increased beta-adrenoreceptor density of rat splenic cell membrane. The immunotoxicity of Cd showed that the proliferation of T-lymphocytes was inhibited and the subsets of T cells were changed. But in the animals with beta-antagonist, the immunotoxicity of Cd on T cells was decreased. It is concluded that beta-adrenoreceptor may play an important role in the mechanism of cadmium on cell immunotoxicity.

Animals↗
PubMed1999

[Clinical significance of Q-Tc dispersion after exercise in aged patients with old myocardial infarction].

OBJECTIVE: This study was aimed to evaluate clinical significance of Q-Tc dispersion after exercise in aged patients with old myocardial infarction. METHOD: Sixty-four aged patients with old myocardial infarction(infarction group) were examined by treadmill exercise, dynamic electrocardiography, echocardiography, and were followed up for average of 24.12 +/- 7.7 months. 30 healthy aged persons were served as control group. RESULTS: Compared with that (40.21 +/- 15.21 ms) before exercise, Q-Tc dispersion (59.37 +/- 20.17 ms) was increased significantly after exercise in infarction group(P < 0.01). But no significant difference was found in Q-Tc dispersion of control group before and after exercise(34.70 +/- 12.29 ms vs 38.91 +/- 13.62 ms P > 0.05). In infarction group, occurrence of abnormal contraction of left ventricular wall, aneurysms, NYHA III class and > III class of Lown's ventricular arrhythmia classification was significantly higher in Q-Tcd > 50 ms patients than that in Q-Tcd < 50 ms ones(P < 0.05). It was found that 5 patients died of cardiac sudden death in Q-Tcd > 50 ms patients and no one died of cardiac sudden death in Q-Tcd < 50 ms ones. CONCLUSION: The Q-Tc dispersion after exercise is an important index to predict ventricular arrhythmia and cardiac death in the patients with old myocardial infarction.

Aged↗
PubMed1999

[Experimental study on antitumor activity of the root of Eurphorbia helioscopia in vivo].

Previous studies showed EWE could strongly inhibit the proliferation of tumor cells in vivo. Experimental results also showed that EWE had antitumor effect in S180-bearing mice and H22-bearing mice and prolonged life-span in S180-bearing mice in this paper, Furthermore, it was found that EWE could improve the immune function of S180-bearing mice. Therefore EWE can be considered as a potent antitumor herb.

Animals↗
PubMed1998

Endomorphins fully activate a cloned human mu opioid receptor.

Endomorphins were recently identified as endogenous ligands with high selectivity for mu opioid receptors. We have characterized the ability of endomorphins to bind to and functionally activate the cloned human mu opioid receptor. Both endomorphin-1 and endomorphin-2 exhibited binding selectivity for the mu opioid receptor over the delta and kappa opioid receptors. Both agonists inhibited forskolin-stimulated increase of cAMP in a dose-dependent fashion. When the mu opioid receptor was coexpressed in Xenopus oocytes with G protein-activated K+ channels, application of either endomorphin activated an inward K+ current. This activation was dose-dependent and blocked by naloxone. Both endomorphins acted as full agonists with efficacy similar to that of [D-Ala2,N-Me-Phe4,Gly-ol5]enkephalin (DAMGO). These data indicate that endomorphins act as full agonists at the human mu opioid receptor, capable of stimulating the receptor to inhibit the cAMP/adenylyl cyclase pathway and activate G-protein-activated inwardly rectifying potassium (GIRK) channels.

Analgesics, Opioid↗