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Biomedical subjects

H Wu

Publications and source records attributed to H Wu.

At least 253 records · Page 14Linked to original sources

Hyalinizing clear-cell carcinoma of salivary glands in fine-needle aspiration.

Hyalinizing clear-cell carcinoma (HCCC) is a recently described distinctive salivary gland neoplasm. Because of its cytoplasmic clearing and the bland nuclear features, HCCC resembles other tumors. The authors describe the cytomorphologic features of four cases of HCCC in fine-needle aspirates (FNA) and discuss the differential diagnosis. Fine-needle aspirates from 4 patients with primary HCCC of minor salivary glands were reviewed. Smears were stained with Diff-Quik and Papanicolaou stains. The cytologic features of the epithelial and the stromal components were analyzed. Cell blocks were prepared, and findings were correlated with prior or subsequent surgical specimens in each case. The smears contained numerous cohesive small and large epithelial cell groups and sheets which had sharp outlines and showed focal nuclear overlapping. The cells had uniform round to ovoid nuclei, granular chromatin, and small nucleoli. The abundant, well-defined cytoplasm was clear in many cells but denser in others. No myoepithelial cells or hyaline globules were identified. HCCC seems to have characteristic cytomorphologic findings on FNA smears. Because these cytologic features are not specific, and overlap with those of a number of salivary gland neoplasms that contain clear cells, a high level of suspicion, clinico-pathologic correlation, and examination of cell blocks are necessary to suggest the diagnosis. A diagnosis of HCCC by FNA was suspected in 3 of the 4 cases reported here.

Adenocarcinoma, Clear Cell↗

Study on angiogenesis factor of human osteosarcoma.

Angiogenesis factor of human osteosarcoma was partially purified and its biological features were studied. The active peptide with 8000 to 10,000 u molecular weight in the conditioned medium obtained from the cultivation of human osteosarcoma cells were partially purified by ultrafiltration, chromatography and dialysis. The angiogenic effects of the fractions were assessed by proliferation assay of human umbilical vein and pig aorta thoracic endothelial cells. The results showed that the chromatography fractions of 4 to 6 could significantly promote the proliferation of the endothelial cells. It was suggested that the human osteosarcoma cells could synthesize and secrete angiogenesis factor with a molecular weight of 8000 to 10,000 u.

Angiogenesis Inducing Agents↗

Effect of coriaria lactone on membrane potential of hippocampal neurons in rats.

Intracellular recording method of electrophysiology was used to study the effect of microinjection of coriaria lactone (CL) into hippocampus on membrane potential of hippocampal neurons in rats. The membrane potential in 34 neurons of 12 rats were recorded. The results showed that CL induced depolarization of all of 34 neurons examined. Among the 34 neurons, 15 had paroxysmal depolarization accompanied by spike discharge in cluster and spike discharge in cluster ceased when membrane was hyperpolarized, 7 showed continuous depolarization accompanied by continuous spike discharge and 12 had only depolarizing response. The results suggest that injection of CL into hippocampus may lead to an increase of excitability of local neurons accompanied by different patterns of epileptioform discharge.

Animals↗

Flow cytometric analysis of DNA content in parotid tumor and its contiguous acini.

To investigate the relationship between proliferative capacity of salivary gland cells in contiguous acini of parotid tumors and recurrent neoplasma, DNA contents of 30 fresh specimens of parotid were studied by using cytometry in tumors, normal and shallow or deep lobe acini of the masses. The results showed that the DI was 1.369, S% 16.95, PI 26.18 in malignant tumors; DI was 1.171, S% 12.41, PI 15.54 in recurrent pleomorphic adenoma; DI was 1.141, S% 12. 74, PI 13.07 in pleomorphic adenoma, DI was 0.999, S% 5.10, PI 8.00 in normal acini. Analysis of variance showed there was a significant difference (P < 0.01). The average DNA contents of shallow on deep lobe of contiguous tumors was 1.08 in DI, 10.65 in S%, 13.49 in PI in malignant tumor, 1.06 in DI, 8.96 in S% and 9.85 in PI in pleomorphic adenoma, which were all higher than in normal acini (P > 0.05). It was concluded that the levels of DI and S% of parotid tumor and its contiguous acini are related to degree of malignancy or recurrent condition of the tumors, suggesting contiguous acini of parotid tumors had the strong capacity of proliferation, which might play an important role in recurrent or malignant change of the parotid tumors.

Adenoma, Pleomorphic↗

Near-tetraploid minimally differentiated acute myeloid leukemia with extensive erythrophagocytosis by leukemic blasts.

Numerical change of chromosomes is common in acute myeloid leukemia (AML). However, a chromosome number as high as near-tetraploidy is very rare, especially in minimally differentiated AML (AML-M0). Erythrophagocytosis by reactive or malignant histiocytes is common in malignant hematological diseases; however, erythrophagocytosis by leukemic blasts is also very rare, especially in AML-M0. We report here the first case of AML-M0 with both of these unique characteristics: a near-tetraploid karyotype and erythrophagocytosis by leukemic blasts.

Acute Disease↗

Induction of vascular adhesion protein-1 during liver allograft rejection and concomitant cytomegalovirus infection in rats.

Vascular adhesion protein-1 (VAP-1) is an adhesion molecule controlling lymphocyte recirculation through high endothelial venules of the lymph nodes. It has also been shown to be induced and to mediate lymphocyte adhesion at sites of inflammation. We studied the expression of VAP-1 and two other inducible adhesion molecules ICAM-1 and VCAM-1 in our experimental model of rat liver allograft rejection and, in addition, the effect of concomitant rat cytomegalovirus (RCMV) infection on this expression. Expression of VAP-1, ICAM-1, and VCAM-1 was studied in rat liver allografts with or without RCMV infection, isografts, and normal rat liver. Immunoperoxidase technique and monoclonal antibodies including a novel anti-VAP-1 reagent were used. VAP-1 expression was induced by acute rejection in sinusoids, hepatocytes, and also in bile ducts, when compared to the isografts or normal liver, where only blood vessels were consistently positive. Sinusoidal and hepatocyte expression of VAP-1 was prolonged by the presence of RCMV. ICAM-1 and VCAM-1 expression was also induced by acute rejection. However, RCMV increased sinusoidal VCAM-1 expression compared to uninfected grafts. The present experimental study shows that VAP-1 is up-regulated in acute rejection of liver allografts, and that this up-regulation is prolonged by RCMV infection.

Acute Disease↗

In vivo expression of the novel CXC chemokine BRAK in normal and cancerous human tissue.

Using differential display, we cloned a gene with reduced expression in short-term explants of head and neck squamous cell carcinoma (HNSCC) tumors compared to cultured normal oral epithelial cells. The differentially expressed gene was identical to the recently cloned CXC chemokine BRAK, which is ubiquitously expressed in normal tissue extracts but is absent from many tumor cell lines in vitro. To define the cell populations expressing BRAK in vivo, in situ mRNA hybridization was performed on normal and cancerous tissues from six different histological sites. The predominant normal cell type constitutively expressing BRAK in vivo was squamous epithelium. Expression in tumors was heterogeneous, with the majority of HNSCCs and some cervical squamous cell carcinomas (SCCs) showing loss of BRAK mRNA. Although absent in unstimulated peripheral blood mononuclear cells, high levels of BRAK were consistently found in infiltrating inflammatory cells (with lymphocyte morphology) in nearly all cancers examined. Furthermore, BRAK expression was demonstrated in B cells and monocytes, after stimulation of peripheral blood mononuclear cells with lipopolysaccharide. This study demonstrates for the first time up-regulation of BRAK mRNA by inflammatory cells in the tumor microenvironment and lost expression from certain cancers in vivo. The data suggest that BRAK may have a role in host-tumor interactions.

Amino Acid Sequence↗

Differential involvement of mu(1)-opioid receptors in endomorphin- and beta-endorphin-induced G-protein activation in the mouse pons/medulla.

Several genetic mouse models of differential sensitivity to opioids have been used to investigate the mechanisms underlying individual variation in responses to opioids. The CXBK mice are inbred recombinant mice which have a lower level of mu(1)-opioid receptors than their parental strain. Endomorphin-1 and endomorphin-2 are endogenous opioid peptides that are highly selective for mu-opioid receptors, while beta-endorphin, which is also an endogenous opioid peptide, is non-selective for mu-, delta- and putative epsilon-opioid receptors. The present study was designed to investigate the effects of these endogenous opioid peptides on G-protein activation by monitoring guanosine-5'-o-(3-[35S]thio)triphosphate binding to pons/medulla membranes of CXBK mice and their parental strain C57BL/6 ByJ mice. Endomorphin-1 (0.1-10 microM), endomorphin-2 (0.1-10 microM) and beta-endorphin (0.1-10 microM) increased guanosine-5'-o-(3-[35S]thio)triphosphate binding to the pons/medulla membranes from C57BL/6 ByJ and CXBK mice in a concentration-dependent manner. However, the increases of guanosine-5'-o-(3-[35S]thio)triphosphate binding induced by either endomorphin-1 or endomorphin-2 in CXBK mice were significantly much lower than those in C57BL/6ByJ mice. However, no significant difference was found in the increases of the guanosine-5'-o-(3-[35S]thio)triphosphate binding induced by beta-endorphin in C57BL/6 ByJ and CXBK mice. Moreover, whereas the increase of guanosine-5'-o-(3-[35S]thio)triphosphate binding induced by 10 microM endomorphin-1 or endomorphin-2 were almost completely blocked by a mu-opioid receptor antagonist beta-funaltrexamine (10 microM) in both strains, the increase of guanosine-5'-o-(3-[35S]thio)triphosphate binding induced by 10 microM beta-endorphin was attenuated to approximately 70% of stimulation by co-incubation with 10 microM beta-funaltrexamine in both strains. The residual stimulation of [35S]guanosine-5'-o-(3-thio)triphosphate binding by 10 microM beta-endorphin in the presence of 10 microM beta-funaltrexamine was further attenuated by the addition of putative epsilon-opioid receptor partial agonist beta-endorphin (1-27) (1 microM) in both strains. Like the endomorphins, the synthetic mu-opioid receptor agonist [D-Ala(2),N-MePhe(4), Gly-ol(5)]enkephalin at 10 microM showed lower increases of guanosine-5'-o-(3-[35S]thio)triphosphate binding in CXBK mice than those in C57BL/6ByJ mice. However, there was no strain difference in the stimulation of guanosine-5'-o-(3-[35S]thio)triphosphate binding induced by 10 microM of the selective delta(1)-opioid receptor agonist [D-Pen(2,5)]enkephalin, delta(2)-opioid receptor agonist [D-Ala(2)]deltorphin II or kappa-opioid receptor agonist U50,488H. The results indicate that the G-protein activation by endomorphin-1 and endomorphin-2 in the mouse pons/medulla is mediated by both mu(1)- and mu(2)-opioid receptors. Moreover, beta-endorphin-induced G-protein activation in the mouse pons/medulla is, in part, mediated by mu(2)- and putative epsilon-, but not by mu(1)-opioid receptors.

Animals↗

Translabyrinthine removal of large acoustic neuromas in young adults.

OBJECTIVE: the authors reviewed the clinical manifestations and the surgical outcomes in a series of young patients who underwent removal of large acoustic neuromas via the translabyrinthine approach. METHODS: 40 young adults who underwent a translabyrinthine removal of acoustic neuromas 3 cm or greater in size were analyzed. The patient's age ranged from 17 to 30 years. The mean size of tumor was 4.25 cm. RESULTS: the primary symptoms are similar to those in adult but usually less intense. The average interval time between the primary symptom and the diagnosis was 17 months. A high percentage of preoperative normal hearing (35%) and good facial function (100%) were noted. Translabyrinthine approach was used in all cases. Total removal was realised in 39 patients (97.5%). The facial nerve was anatomically preserved in 37 patients (92.5%). Twenty-six patients (65%) had a good facial function (House-Brackmann grade I or II) immediately or at 1 month after surgery, 11 patients (28%) achieved grade III or IV. Three patients underwent an immediate nerve repair after tumor removal. All of them recovered to grade III or IV 1 year after surgery. Postoperative complications were minimal. CONCLUSIONS: young adults may have a rapid growth rate but usually have minimal symptoms even with a large acoustic neuroma. The translabyrinthine approach has been used successfully in removal of large acoustic tumors of young patients, with the good result of facial nerve preservation and long-term tumor control.

Adolescent↗

Comparison of debulking followed by stenting versus stenting alone for saphenous vein graft aortoostial lesions: immediate and one-year clinical outcomes.

OBJECTIVES: We compared in-hospital and one-year clinical outcomes in patients undergoing debulking followed by stent implantation versus stenting alone for saphenous vein graft (SVG) aortoostial lesions. BACKGROUND: Stent implantation in SVG aortoostial lesions may improve procedural and late clinical outcomes. However, the impact of debulking before stenting in this complex lesion subset is unknown. METHODS: We studied 320 consecutive patients (340 SVG aortoostial lesions) treated with Palmaz-Schatz stents. Debulking with excimer laser or atherectomy was performed in 133 patients (139 lesions) before stenting (group I), while 187 patients (201 lesions) underwent stent implantation without debulking (group II). Procedural success and late clinical outcomes were compared between the groups. RESULTS: Overall procedural success (97.6%) was similar between the groups. Procedural complications were also similar (2.2% for group I and 2.6% for group II). At one-year follow-up, target lesion revascularization (TLR) was 19.4% for group I and 18.2% for group II (p = 0.47). There was no difference in cumulative death or Q wave myocardial infarction between the groups. Overall cardiac event-free survival was similar (69% for group I and 68% for group II). By Cox regression analysis, the independent predictors of late cardiac events were final lumen cross-sectional area (CSA) by intravascular ultrasound (IVUS) (p = 0.001) and restenotic lesions (p = 0.01). Similarly, final IVUS lumen CSA (p = 0.0001) and restenotic lesions (p = 0.006) were found to predict TLR at one year. CONCLUSIONS: These results suggest that, in most patients with SVG aortoostial lesions, debulking before stent implantation may not be necessary.

Aged↗

Acute type 5 phosphodiesterase inhibition with sildenafil enhances flow-mediated vasodilation in patients with chronic heart failure.

OBJECTIVES: To determine the acute effects of type 5 phosphodiesterase inhibition with sildenafil on flow-mediated vasodilation in the brachial artery of patients with chronic heart failure. BACKGROUND: Impaired endothelium-dependent, flow-mediated vasodilation in patients with heart failure is partly attributable to hyporesponsiveness of cyclic guanosine monophosphate (cGMP) mediated vasorelaxation effector mechanisms in vascular smooth muscle. The effect of inhibition of cGMP degradation with sildenafil, a specific type 5 cGMP phosphodiesterase inhibitor, on flow-mediated dilation in heart failure is unknown. METHODS: Flow-mediated vasodilation after release of 1, 3 and 5 min of transient arterial occlusion was measured in the brachial artery with high resolution two-dimensional ultrasound imaging in 48 patients with chronic heart failure before and 1 h after randomized, double-blind assignment to a single oral dose of sildenafil 12.5, 25 or 50 mg or matching placebo. RESULTS: In response to oral administration of a single dose of study drug, the change in flow-mediated vasodilation after release of 1, 3 and 5 min of arterial occlusion was significantly greater in patients receiving sildenafil 25 mg (3.3 +/- 1.9, 3.8 +/- 1.8 and 4.0 +/- 1.8%, respectively, p < 0.05) and patients receiving sildenafil 50 mg (3.7 +/- 1.3, 4.1 +/- 1.1, 3.9 +/- 1.3%, respectively, p < 0.05) than that of patients receiving placebo (0.7 +/- 1.1, 0.2 +/- 1.2, 0.6 +/- 0.8%, respectively). CONCLUSIONS: Acute type 5 phosphodiesterase inhibition with sildenafil 25 and 50 mg increases endothelium-dependent, flow-mediated vasodilation in patients with chronic heart failure when compared with placebo.

Blood Circulation↗

Influence of diabetes mellitus on early and late clinical outcomes in saphenous vein graft stenting.

OBJECTIVES: The purpose of this study was to compare early and late clinical outcomes in diabetic and nondiabetic patients after stent implantation in saphenous vein grafts (SVG). BACKGROUND: Patients with diabetes mellitus have less favorable acute and long-term outcomes after stent implantation in native coronary arteries. The impact of diabetes on SVG stenting, however, is not known. METHODS: We studied 908 consecutive patients (1,366 SVG lesions) treated with Palmaz-Schatz stents. In-hospital and late clinical outcomes (death, Q-wave myocardial infarction and repeat revascularization rates at one year) were compared between diabetic (n = 290) and nondiabetic (n = 618) patients. RESULTS: In-hospital mortality was significantly higher in diabetic as compared with nondiabetic patients (2.2% vs. 0.3%, p = 0.003). At one-year follow-up, target lesion revascularization (TLR) was 16.6% in diabetic and 12.3% in nondiabetic patients (p = 0.03). Overall cardiac event-free survival (freedom from death, Q-wave myocardial infarction and any coronary revascularization procedure) at one year was significantly lower in the diabetic (68%) compared with the nondiabetic patients (79%, p = 0.0003). By Cox regression analysis, diabetes mellitus was an independent predictor of both TLR (relative risk: 1.23; confidence interval: 0.96 to 1.58; p = 0.004) and late cardiac events (relative risk: 1.40; confidence interval: 1.05 to 1.86; p = 0.02). CONCLUSIONS: Patients with diabetes undergoing stent implantation in SVG have: 1) higher in-hospital and late mortality, 2) higher one-year TLR rates, and 3) significantly lower one-year cardiac event-free survival. Thus, diabetic patients have less favorable acute and late clinical outcomes after stent implantation in SVG lesions.

Aged↗

Hepatosplenic and subcutaneous panniculitis-like gamma/delta T cell lymphomas are derived from different Vdelta subsets of gamma/delta T lymphocytes.

Gamma/delta T cell lymphomas (gamma/delta TCL) represent rare, often aggressive types of T cell malignancy that are clinically and pathologically diverse. Most gamma/delta TCL occur as a hepatosplenic or subcutaneous type. To date, analysis of the T cell receptor delta (TCRS) gene repertoire of hepatosplenic gamma/delta TCL (gamma/delta HSTCL) and subcutaneous panniculitis-like gamma/delta TCL (gamma/delta SPTCL) has been reported only in a limited number of cases. In this study we analyzed 11 gamma/delta HSTCL and 4 gamma/delta SPTCL by polymerase chain reaction and immunostaining to determine their usage of the Vdelta subtypes (Vdelta1-6). It is noteworthy that 10 of 11 gamma/delta HSTCL expressed the Vdelta1 gene. The remaining case also expressed T cell receptor delta (TCRS) as determined by flow cytometry and TCRdelta rearrangement in Southern blot. However, the Vdelta gene expressed by this lymphoma could not be determined, which suggests usage of an as yet unidentified Vdelta gene. In striking contrast to the gamma/delta HSTCL, all 4 gamma/delta SPTCL expressed the Vdelta2 gene. Our data demonstrate that gamma/delta HSTCL are preferentially derived from the Vdelta1 subset of gamma/delta T lymphocytes, whereas gamma/delta SPTCL are preferentially derived from the Vdelta2 subset. The pattern of Vdelta gene expression in HSTCL and SPTCL corresponds to the respective, predominant gamma/delta T cell subsets normally found in the spleen and skin. This finding suggests that gamma/delta TCL are derived from normal gamma/delta T lymphocytes which reside in the affected tissues. Furthermore, the selective, lymphoma type-specific Vdelta gene segment usage may provide a molecular tool to distinguish better among various types of gamma/delta TCL lymphoma particularly in the clinically advanced, widely disseminated cases.

Adolescent↗

Allelochemicals in wheat (Triticum aestivum l.): variation of phenolic acids in root tissues.

Analysis by GC/MS/MS showed that a worldwide collection of 58 wheat accessions differed significantly in the production of seven phenolic acids in the roots of 17-day-old wheat seedlings. The allelochemical contents among wheat accessions ranged from 24.5 to 94.5, 19.9 to 91.7, 3.7 to 15.4, 2.2 to 38.6, 1.0 to 42.2, 19.3 to 183.6, and 11.7 to 187.6 mg/kg of root dry weight for p-hydroxybenzoic, vanillic, cis-p-coumaric, syringic, cis-ferulic, trans-p-coumaric, and trans-ferulic acids, respectively. trans-Ferulic acid was identified as the most predominant phenolic acid in the roots. Phenolic acids, with the exception of syringic acid, were more concentrated in roots than in shoots. Significant correlation was found between the roots and the shoots in the contents of vanillic, cis-p-coumaric, syringic, trans-p-coumaric, and trans-ferulic acids, and in the content of each structural group of phenolic acids. Wheat accessions with high levels of total identified phenolic acids in the roots were generally strongly allelopathic to the growth of annual ryegrass.

Carboxylic Acids↗

Structural studies of the glycopeptides of B-chain of cinnamomin--a type II ribosome-inactivating protein by nuclear magnetic resonance.

Cinnamomin is a plant type II ribosome-inactivating protein (RIP) isolated from the seeds of Cinnamomum camphora. It consists of two nonidentical polypeptide chains (A- and B-chain) held together through one disulfide linkage. Its A- and B-chain contain 0.3% and 3.9% sugars respectively. The B-chain of cinnamomin was digested by pronase E and then the liberated glycopeptides were separated from non-glycopeptides by gel filtration chromatography on a Bio-Gel P-4 column. Three crude glycopeptides were obtained by continuing chromatography over anion-exchange resin (AG1-X2) in the buffer of 2% pyridine-acetic acid (pH 8.3) with a polygradient elution system. Through further purification by the gel filtration chromatography and HPLC, three major glycopeptides, GP1, GP2 and GP3 were obtained. Mainly by two-dimensional Nuclear Magnetic Resonance (NMR) including TOCSY, DQF-COSY, NOESY, HMQC and HMBC, their primary structures were analyzed as: Man\balpha1,3Man\balpha1,6(Man\balpha1,3)(Xyl\bbeta1,2)Man\bbeta1,4GlcNAc\bbeta1,4GlcNAc\bbeta1-(Gly-)Asn-Asn-Thr(GP1), Man\balpha1,6(Man\balpha1,3)(Xyl\bbeta1,2)Man\bbeta1,4GlcNAc\bbeta1,4(Fuc\balpha1,3)GlcNAc\bbeta1-Asn-Ala-Thr(GP2),Man\balpha1,6(Man\balpha1,3)Man\balpha1,6(Man\balpha 1,2 Man\balpha1,3)Man\bbeta1,4GlcNAc\bbeta1,4GlcNAc\bbeta1-(Ala-)Asn-Gly-Thr(GP3).

Algal Proteins↗

Solution structure of a dynein motor domain associated light chain.

Dyneins are molecular motors that translocate towards the minus ends of microtubules. In Chlamydomonas flagellar outer arm dynein, light chain 1 (LC1) associates with the nucleotide binding region within the gamma heavy chain motor domain and consists of a central leucine-rich repeat section that folds as a cylindrical right handed spiral formed from six beta-beta-alpha motifs. This central cylinder is flanked by terminal helical subdomains. The C-terminal helical domain juts out from the cylinder and is adjacent to a hydrophobic surface within the repeat region that is proposed to interact with the dynein heavy chain. The position of the C-terminal domain on LC1 and the unexpected structural similarity between LC1 and U2A' from the human spliceosome suggest that this domain interacts with the dynein motor domain.

Amino Acid Motifs↗