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H Y Yang

Publications and source records attributed to H Y Yang.

At least 91 records · Page 5Linked to original sources
PubMed1994

[The metastatic pattern of malignant tumors].

Four hundred autopsy cases of malignant tumors were analysed. Of these 321 cases (80.3%) had carcinoma and 79 (19.7%) sarcoma. In the 79 cases, 65 had malignant lymphoma, and 14 (3.5%) soft tissue and bone tumor. The tumor cells metastatic to the lung and liver were common in the autopsy cases. There were 163 cases of metastatic tumors in the lung and liver respectively (40.5%). The metastatic tumor in the liver was mainly from the breast, large intestinal, ovary, stomach and NHL, and in the lung mainly from the breast, liver, NHL, stomach and ovary. The lymph node metastasis was mainly located in the neck, mediastina, aorta. The extensive metastatic tumors were lung cancer, gastric cancer, breast cancer and NHL, However, carcinoma in uterus cervix, urinary bladder, pharynex and testis was mainly infiltrated in the original region. The tumor metastasis was related to the region, histologic type and differentiation and so on.

Adenocarcinoma↗
PubMed1994

Helicobacter pylori infection and chronic active gastritis.

Helicobacter pylori (H. pylori) is an S-Shaped, gram-negative bacillus that recently has been implicated in the pathogenesis of chronic active gastritis and other peptic ulcer disease. These findings have encouraged gastroenterologists to provide a new rationale for patient management, with hope of providing more successful treatment of peptic ulcer disease, particularly gastritis. Therefore, a cooperative diagnostic effort was made at the pathology laboratory of St Francis Medical Center to adopt a simple and reliable method for the identification of H. pylori in tissue sections of endoscopic biopsies of stomach and duodenum. We attempted to estimate the prevalence of H. pylori infection in patients biopsied for upper Gl disorders who were refractory to medication. A prevalence of H. pylori infection among different ethnic groups also was studied.

Adult↗
PubMed1993

Expression of 300-kilodalton intermediate filament-associated protein distinguishes human glioma cells from normal astrocytes.

The availability of biochemical markers to distinguish glioma cells from normal astrocytes would have enormous diagnostic value. Such markers also may be of value in studying the basic biology of human astrocytomas. The vimentin-binding, 300-kDa intermediate filament (IF)-associated protein (IFAP-300kDa) has recently been shown to be developmentally expressed in radial glia of the central nervous system of the rat. It is not detected in the normal or reactive astrocytes of the adult rat nor in neonatal rat brain astrocytes in primary culture. In the present study, double-label immunofluorescence microscopy using antibodies to IFAP-300kDa and glial fibrillary acidic protein (GFAP, an astrocyte-specific IF structural protein) identifies this IFAP in GFAP-containing tumor cells from examples of all three major types of human astrocytomas (i.e., well-differentiated, anaplastic, and glioblastoma multiforme). Astrocytoma cells in primary cultures prepared from all three astrocytomas also express this protein. It is not detectable in normal adult brain tissue. Immunoblot analyses using the IFAP-300kDa antibody confirm the presence of a 300-kDa polypeptide in fresh astrocytoma preparations enriched for IF proteins. These results suggest the utility of IFAP-300kDa as a marker for identification of human glioma cells both in vitro and in situ.

Astrocytes↗
PubMed1993

Immunotyping of radial glia and their glial derivatives during development of the rat spinal cord.

The differentiation of glia in the central nervous system is not well understood. A major problem is the absence of an objective identification system for involved cells, particularly the early-appearing radial glia. The intermediate filament structural proteins vimentin and glial fibrillary acidic protein have been used to define the early and late stages, respectively, of astrocyte development. However, because of the non-specificity of vimentin and the temporal overlap in expression patterns of both proteins, it is difficult to refine our view of the process. This is especially true of the early differentiation events involving radial glia. Using the developmentally-expressed intermediate filament-associated protein IFAP-70/280 kD in conjunction with vimentin and glial fibrillary acidic protein markers, a comprehensive investigation of this problem was undertaken using immunofluorescence microscopy of developing rat spinal cord (E13-P28 plus adult). The phenotypes of the cells were defined on the basis of their immunologic composition with respect to IFAP-70/280 kD (I), vimentin (V) and GFAP (G). A definitive immunotype for radial glia was established, viz, I+/V+/G-; thus reliance upon strictly morphological criteria for this early developmental cell was no longer necessary. Based upon the immunotypes of the cells involved, four major stages of macroglial development were delineated: (1) radial glia (I+/V+/G-); (2) macroglial progenitors (I+/V+/G+); (3) immature macroglia (I-/V+/G+); and (4) mature astrocytes (I-/V+/G+ primarily in white matter and I-/V-/G+, the predominant type in gray matter). It is of interest to note that the cells of the floor plate were distinguished from radial glia by their lack of IFAP-70/280 kD immunoreactivity. Introduction of the IFAP-70/280 kD marker has therefore provided a more refined interpretation of the various differentiation stages from radial glia to mature astrocytes.

Animals↗
PubMed1993

Distinct associations of HLA class II genes with inflammatory bowel disease.

BACKGROUND: There are relatively few studies of HLA class II association either with Crohn's disease (CD) or ulcerative colitis (UC). The few available association studies have been carried out by serological techniques, and the results from these studies are inconclusive. METHODS: The association between HLA class II genes was studied using molecular genotyping in combination with allele-specific oligonucleotide hybridization by polymerase chain reactions. RESULTS: In UC (n = 74), we observed a positive association with the HLA DR2 allele (P = 0.008) and negative associations with the DR4 (P = 0.018) and DRw6 (P = 0.028) when compared with ethnically matched controls (n = 77). No associations were observed with any DQ alleles. In contrast, in CD (n = 95) we observed a positive association with the combination of DR1 and DQw5 alleles (P = 0.021). Furthermore, stratifying DR1 and DQw5 alleles indicated that neither allele was independently associated with CD, suggesting that the association was with the haplotype rather than either of the alleles individually. A suballele of DQw5, DQB1*0501, contributed this haplotypic association (P = 0.012). CONCLUSIONS: DR and DQ molecules firmly separate UC and CD on genetic grounds, suggesting that the contribution of the HLA class II genes to the disease susceptibility is quite different for the two disorders.

Alleles↗
PubMed1993

Subcutaneous injection of an analog of neuropeptide FF precipitates morphine abstinence syndrome.

Neuropeptide FF (NPFF) has been shown to exert various antiopiate actions, including precipitation of opiate abstinence syndrome by third ventricle injection in morphine dependent rats. In the present study, dansyl-Pro-Gln-Arg-Phe-amide, a lipophilic analog of NPFF, was injected into morphine dependent rats and appropriate sham controls at a dose of 9 mg/kg s.c. Comparison groups were injected with ethanol/water vehicle alone. The NPFF analog precipitated a vigorous opiate abstinence syndrome in morphine dependent rats, but not in sham controls.

Amino Acid Sequence↗
PubMed1993

Antiserum against neuropeptide Y enhances the nicotine-mediated release of catecholamines from cultured rat adrenal chromaffin cells.

A primary culture of chromaffin cells was prepared from adult rats and the stability of cell contents, NPY and catecholamines (CAs), during the culture was studied. The responsiveness of cultured chromaffin cells to NGF or secretagogues and the possible role of NPY on the CA secretion from cultured chromaffin cells were investigated. After plating of isolated cells, there was marked decrease in the cell content of CAs but a significant increase in the cell content of NPY. Though both NPY and CAs in the cultured cells were positively regulated by NGF, the results of this study seemed to suggest a differential regulation for NPY and CAs in the chromaffin cell. The cultured chromaffin cells secreted NPY and CAs in response to stimulation by nicotine. The nicotine stimulated secretion of CA was enhanced by the presence of IgG fraction, prepared from NPY antiserum, in the secretion medium. The results suggested that NPY was co-released with CAs from chromaffin cells and then acted as a modulator on CA secretion.

Adrenal Glands↗
PubMed1993

Modulation of neuropeptide FF receptors by guanine nucleotides and cations in membranes of rat brain and spinal cord.

Using a radioligand binding assay, we examined ionic modulation and G protein coupling of neuropeptide FF (NPFF) receptors in membranes of rat brain and spinal cord. We found that NaCl (but not KCl or LiCl) and MgCl2 increased specific 125I-YLFQPQRFamide (125I-Y8Fa) binding to NPFF receptors in both tissues in a dose-dependent manner, with optimal conditions being 60 mM NaCl and 1 mM MgCl2. Guanine nucleotides dose-dependently inhibited specific 125I-Y8Fa binding to rat brain and spinal cord membranes with maximal effects of 64 +/- 6 and 71 +/- 2%, respectively. The order of potency was nonhydrolyzable GTP analogues > GTP > or = GDP >> GMP, ATP. The guanine nucleotide inhibition was observed in the absence and presence of NaCl and MgCl2. The mechanism of inhibition in spinal cord membranes appeared to be a reduction in the number of NPFF receptors; in one experiment, control KD and Bmax values were 0.068 nM and 7.2 fmol/mg of protein, respectively, and with 0.1 microM guanylylimidodiphosphate the respective values were 0.081 nM and 4.9 fmol/mg, a 32% reduction in receptor number. Similar results were obtained with guanosine 5'-O-(3-thiotriphosphate). Our data suggest that 125I-Y8Fa binding sites in rat CNS are G protein-coupled NPFF receptors regulated by GTP and cations.

Amino Acid Sequence↗
PubMed1993

Origin of neurohypophyseal neuropeptide-FF (FLFQPQRF-NH2).

Neuropeptide-FF (FLFQPQRF-NH2), originally isolated from bovine brain, is an FMRF-NH2-like peptide with morphine-modulating activity. Neuropeptide-FF (NPFF) is unevenly distributed in the central nervous system, with the highest concentrations in posterior pituitary and spinal cord. In the rat pituitary, NPFF is found exclusively in the neural lobe, where it is localized in nerve terminals and fibers, indicating the hypothalamus as a possible source of the neural lobe NPFF. In this study the origin of neurohypophyseal NPFF was investigated using various hypothalamic lesions and an anterograde tracing experiment. The results suggest that at least part of the neurohypophyseal NPFF originates from the supraoptic nucleus and may be localized in some of the arginine vasopressin-containing magnocellular neurons.

Amino Acid Sequence↗
PubMed1993

Neuropeptide FF receptors: structure-activity relationship and effect of morphine.

Neuropeptide FF (FLFQPQRFamide, NPFF) is an octapeptide implicated in morphine analgesia, tolerance and dependence. Many of the behavioral effects of NPFF have also been observed with the invertebrate neuropeptide Phe-Met-Arg-Phe-amide (FMRFamide), which binds to NPFF receptors because of its low homology to the C-terminal portion of NPFF. A competitive ligand binding assay was used to characterize NPFF receptors in rat spinal cord and a strong requirement was found for the C-terminal Arg-Phe-amide. It was found that FMRFamide (Ki = 1.8 nM) bound with lower affinity than NPFF (0.26 nM) but it was about 7-fold more potent than PQRFamide (12 nM). This finding explains the similar bioactivities of NPFF and FMRFamide. The Gln2 appeared to be the cause of the relatively low potency of PQRFamide, based on the binding specificity of NPFF receptors for a series of FMRFamide analogs. In contrast to the Arg-Phe-amide, substitutions at the first and second positions of FMRFamide were generally tolerated, with the most potent analogs being PMRFamide (Ki = 0.54 nM), FFRFamide (0.25 nM) and FWRFamide (0.42 nM). Among the most potent ligands was a pentapeptide containing a photoreactive Phe analog, D-Tyr-(p-benzoyl-Phe)-norLeu-Arg-Phe-amide (Ki = 0.23 nM). It was found that dansyl-PQRFamide and dansyl-RFamide also bound to NPFF receptors with Ki values of 6.1 and 73 nM, respectively. The radioligand binding and G-protein coupling of NPFF receptors were not altered by chronic morphine treatment.

Amino Acid Sequence↗
PubMed1993

[Experimental study on the action of EDTA-liposome to remove mercury from the mice given methylmercury chloride].

It was reported that experimental study on the action of EDTA-Liposome to remove mercury from the mice given methylmercury chloride showed that elimination of methylmercury chloride from brain, testicle, liver, kidney and blood of mice treated by EDTA-Liposome was more significant than that of mice treated by EDTA alone. Mercury level in feces of EDTA-Liposome treated group increased significantly (P < 0.001). The advantages of treatment with EDTA-Liposome were discussed. Applying EDTA-Liposome is an efficient method in therapy of metal poisoning.

Animals↗
PubMed1993

[Neck mass].

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Adult↗
PubMed1993

Hemodynamic evaluation of bovine pericardial xenograft valves in the mitral position by stress Doppler echocardiography.

The function of a bovine pericardial xenograft valve in the mitral position was studied in 18 patients by using stress Doppler echocardiography after submaximal supine exercise. In 10 patients with normally functioning tissue valve, peak and mean gradients increased from 9.3 +/- 1.3 and 2.7 +/- 0.7 mmHg, respectively at rest, to 14.7 +/- 0.9 and 4.1 +/- 1.0 mmHg at peak exercise. The tissue valve area assessed by the Doppler pressure half-time method increased from 2.69 +/- 0.38 cm2 at rest, to 3.15 +/- 0.38 cm2 at peak exercise (P < 0.05). In 6 patients with mitral regurgitation, peak and mean gradients increased from 17.3 +/- 5.3 and 7.0 +/- 1.8 mmHg, respectively at rest, to 24.3 +/- 5.0 and 9.0 +/- 2.6 mmHg at peak exercise, but there was no significant change in valve area at peak exercise. Patients with severe isolated mitral regurgitation had a Vmax of more than 2 m/s and elevated pressure gradients at peak exercise. But the pressure half-time was relatively unaffected, allowing their differentiation from patients with tissue valvular stenosis. Stress Doppler echocardiography is a simple, noninvasive and reliable method for the evaluation of the mitral tissue valve function which is recommendable for patients with suspected mitral tissue valve dysfunction.

Adult↗
PubMed1992

Release of neuropeptide FF (FLFQPQRF-NH2) from rat spinal cord.

Neuropeptide FF (FLFQPQRF-NH2), originally isolated from bovine brain, is an FMRF-NH2-like peptide with morphine-modulating activity. Neuropeptide FF (NPFF) is highly localized in the dorsal spinal cords where there are also specific NPFF binding sites. Furthermore, there have been studies indicating that NPFF may participate in the regulation of pain threshold in the spinal cord. However, whether NPFF can be released from the spinal cord is not known. The present experiments, using an in vitro superfusion of an isolated whole rat spinal cord, demonstrated that high concentrations of KCl or substance P caused a release of NPFF immunoreactive material (IR) from the spinal cord into the perfusion medium in a calcium-dependent manner. Substance P (1-11) also produced a detectable release of NPFF-IR in vivo although the response was quite variable. The released NPFF-IR was analyzed by an HPLC study and found to consist of NPFF and other minor immunoreactive peptides. Further studies with substance P-related peptides showed that the in vitro release of NPFF-IR could also be induced by substance P (1-7) but not by [pGlu5,Me-Phe8,Sar9]-substance P (5-11) or substance K. These results suggest that the specific substance P receptor (SP-N), which is recognized by both substance P (1-11) and substance P (1-7) rather than the tachykinin receptor, is involved in NPFF secretion from the spinal cord. In view of the role of substance P (1-11) and substance P (1-7) in sensory transmission, the results of this study further support the role of NPFF in the modulation of antinociception in the spinal cord.

Amino Acid Sequence↗
PubMed1992

Distinct developmental subtypes of cultured non-stellate rat astrocytes distinguished by a new glial intermediate filament-associated protein.

The nature and tissue origin of cultured non-stellate astrocytes have not been defined. On the basis of immunofluorescence microscopy using multiple double-labeling with antibodies to glial fibrillary acidic protein (GFAP), vimentin, and the recently identified intermediate filament-associated protein (IFAP)-70/280kD, four distinct astrocytic subtypes were definable in neonatal rat brain astrocytes in culture. All of these were of the non-stellate type on the basis of morphology. Similar examination of developing rat cerebral cortex identified these same subtypes as distinct differentiation states of astrocytes. These findings indicate that the parallel developmental events can be studied in vitro.

Animals↗
PubMed1992

Colchicine-sensitive and colchicine-insensitive intermediate filament systems distinguished by a new intermediate filament-associated protein, IFAP-70/280 kD.

A monoclonal antibody was produced, using as antigen a BHK-21 cytoskeletal preparation enriched in intermediate filaments (IF) and their associated proteins. This antibody reacted exclusively with a reproducible set of 70-280 kD polypeptides present in minor quantities in this preparation, as detected by immunoblot analysis. Based upon several criteria, this immunologically related group of polypeptides was designated as IFAP-70/280 kD (IF-Associated Protein): (1) it co-isolated with IF in vitro, (2) it co-localized (by both immunofluorescence and immunoelectron microscopy) with IF in situ in all stages of cell spreading, and (3) it segregated in vitro with the 54/55 kD (desmin/vimentin) structural IF subunit proteins of BHK cells through two cycles of in vitro disassembly/assembly. Immunogold labeling further localized IFAP-70/280 kD to regions of parallel or loosely bundled IF in situ, suggesting a role in regulating the supramolecular organization of IF. When this monoclonal antibody was used for double-label immunofluorescence observations of colchicine-treated BHK cells, it demonstrated the presence of colchicine-sensitive and colchicine-insensitive IF. Anti-IFAP-70/280 kD localized entirely to the drug-induced juxtanuclear IF cap, while a polyclonal antibody directed against the desmin/vimentin structural IF subunits and the previously characterized monoclonal anti-IFAP-300 kD [Yang et al., 1985; J. Cell Biol. 100:620] localized to both the juxtanuclear IF cap and a colchicine-insensitive IF network peripheral to the cap in the same cells. The colchicine-insensitive IF pattern often exhibited similarities to that observed for the actin-based stress fiber system, suggesting that stress fiber association may be an additional factor in IF organization.

Animals↗
PubMed1992

Two-locus mitochondrial and nuclear gene models for mitochondrial disorders.

Stimulated by a large pedigree with a cochlear form of deafness, for which we considered a two-locus mitochondrial and nuclear gene model, we have extended the classic methods of segregation analysis to these classes of two-locus disorders. Based on the unique maternal transmission pattern of the mitochondria, we demonstrate that utilization of the maternal line pedigree allows us to simplify the various two-locus mitochondrial models to "one nuclear locus" models. Classifying the nuclear families into different independent groups by the mother's phenotypes allows us to estimate the nuclear gene frequency in one group and to use this estimate as the expected value to test the fitness of the model on the other group. In addition, if we restrict the analysis to specific subsets of the mating type(s), we can also test the model on specific groups of nuclear families without estimating the gene frequency. Goodness-of-fit tests can be performed on pooled sibship data as well as individual sibship data. These methods of analysis should assume increasing importance as more disorders with features of mitochondrial inheritance are identified.

Cell Nucleus↗