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Y Cao

Publications and source records attributed to Y Cao.

At least 163 records · Page 9Linked to original sources
PubMed2000

Antibodies to squalene in Gulf War syndrome.

Gulf War Syndrome (GWS) is a multisystemic illness afflicting many Gulf War-era veterans. The molecular pathological basis for GWS has not been established. We sought to determine whether the presence of antibodies to squalene correlates with the presence of signs and symptoms of GWS. Participants in this blinded cohort study were individuals immunized for service in Desert Shield/Desert Storm during 1990-1991. They included 144 Gulf War-era veterans or military employees (58 in the blinded study), 48 blood donors, 40 systemic lupus erythematosus patients, 34 silicone breast implant recipients, and 30 chronic fatigue syndrome patients. Serum antibodies to squalene were measured. In our small cohort, the substantial majority (95%) of overtly ill deployed GWS patients had antibodies to squalene. All (100%) GWS patients immunized for service in Desert Shield/Desert Storm who did not deploy, but had the same signs and symptoms as those who did deploy, had antibodies to squalene. In contrast, none (0%) of the deployed Persian Gulf veterans not showing signs and symptoms of GWS have antibodies to squalene. Neither patients with idiopathic autoimmune disease nor healthy controls had detectable serum antibodies to squalene. The majority of symptomatic GWS patients had serum antibodies to squalene.

Autoantibodies↗
PubMed2000

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Explore the source record for details and available documents.

Journal Article↗
PubMed2000

Tamponade after open-heart surgery with percutaneous cardiopulmonary support.

A 56-year-old man presented with late cardiac tamponade appearing on 9 postoperative day after weaning from percutaneous cardiopulmonary support. He had been referred to our hospital for congestive heart failure. He underwent aortic valve replacement and fell into postcardiotomy low output syndrome. He could not be weaned from extracorporeal circulation, and we had to use an intraaortic balloon pump and percutaneous cardiopulmonary support. On postoperative day 9, percutaneous cardiopulmonary support was successfully withdrawn without problems, but he showed signs of superior vena cava syndrome after the cannulas were removed. An echocardiogram also showed cardiac tamponade. When the wound was reopened, a lot of old clots had compressed the right atrium and, after clot removal, the patient's hemodynamic state improved markedly. It is important to be aware that percutaneous cardiopulmonary support may conceal hemodynamic deterioration due to cardiac tamponade and to take care that a patient does not experience hemodynamic deterioration after percutaneous cardiopulmonary support withdrawal.

Cardiac Output, Low↗
PubMed2000

Expression of MUC1, Thomsen-Friedenreich-related antigens, and cytokeratin 19 in human renal cell carcinomas and tubular clear cell lesions.

The expression of MUC1, MUC2, mucin-associated Thomsen-Friedenreich-related antigens (TF, sialosyl-TF, Tn, and sialosyl-Tn), and cytokeratin 19 (CK19) was systematically investigated in situ in 58 resected human kidney tumours, surrounding tissue of normal appearance, and two normal kidneys obtained at autopsy, using monoclonal antibodies. In kidney tissues of normal appearance, TF, s-TF, MUC1 and CK19 were positive in distal tubules and collecting ducts but negative in proximal tubules. In contrast, MUC2, Tn, and s-Tn were negative throughout the normal renal tubular system. Almost all renal cell carcinomas (RCCs) showed strong immunoreactivity for MUC1, but all were negative for MUC2. Some RCCs expressed TF, Tn, s-Tn, and CK19. In addition, the immunomorphological characteristics of the majority of clear-cell RCCs and clear/granular RCCs with anti-MUC1 and anti-CK 19 closely resembled those of the collecting duct and the distal tubule rather than the proximal tubule. In the renal tissue of otherwise normal appearance adjacent to clear-cell RCCs and clear/granular RCCs, clear cells with excessive storage of glycogen were often found in the collecting duct system, but only rarely in the proximal tubules. These results suggest that the majority of clear-cell RCCs and clear/granular RCCs may originate from the collecting duct system.

Adenoma, Oxyphilic↗
PubMed2000

R127W-HNF-4alpha is a loss of function mutation but not a rare polymorphism and causes Type II diabetes in a Japanese family with MODY1.

AIMS/HYPOTHESIS: Mutations in the hepatocyte nuclear factor (HNF)-4alpha gene cause the type 1 form of maturity-onset diabetes of the young (MODY1). The R127W mutation is a missense mutation located in the T-box region of HNF-4alpha that was first identified in a Japanese family with MODY. We have examined the functional properties of this mutation in order to clarify the molecular basis of MODY1. METHODS: The intracellular localisation, DNA binding ability, transactivation activity and functional synergism with the coactivator CREB-binding protein (CBP) of R127W-HNF-4alpha were investigated. RESULTS: The nuclear import and functional synergy with CBP of R127W-HNF-4alpha were normal. The DNA binding ability of the mutant was decreased as was its transcriptional activation of the HNF-1alpha and L-type pyruvate kinase (PKL) genes. CONCLUSION/INTERPRETATION: The R127W mutation seems to be a loss-of-function mutation.

Basic Helix-Loop-Helix Leucine Zipper Transcriptio↗
PubMed2000

Monophyletic origin of the order chiroptera and its phylogenetic position among mammalia, as inferred from the complete sequence of the mitochondrial DNA of a Japanese megabat, the Ryukyu flying fox (Pteropus dasymallus).

Complete sequences of mitochondrial DNA (mtDNA) are useful for the reconstruction of phylogenetic trees of mammals and, in particular, for inferring higher-order relationships in mammals. In this study, we determined the complete sequence (16,705 bp) of the mtDNA of a Japanese megabat, the Ryukyu flying fox (Pteropus dasymallus). We analyzed this sequence phylogenetically by comparing it with the complete sequence of mtDNAs of 35 mammals in an effort to reevaluate the enigmatic relationship between Megachiroptera and Microchiroptera and the relationships between them and other mammals. Maximum-likelihood analysis of 12 concatenated mitochondrial proteins from 36 mammals strongly suggested the monophyly of the order Chiroptera and its close relationship to Fereuungulata (Carnivora + Perissodactyla + Cetartiodactyla). We estimated that megabats and microbats diverged approximately 58 MyrBP and discussed the origin and early evolution of Chiroptera based on our findings.

Animals↗
PubMed2000

Design and development of selective muscarinic agonists for the treatment of Alzheimer's disease: characterization of tetrahydropyrimidine derivatives and development of new approaches for improved affinity and selectivity for M1 receptors.

Cholinergic neurons degenerate in Alzheimer's disease, resulting in cognitive impairments and memory deficits, and drug development efforts have focused on selective M1 muscarinic agonists. 5-(3-Ethyl-1,2,4- oxadiazol-5-yl)-1,4,5,6-tetrahydropyrimidine trifluoroacetic acid (CDD-0102) stimulates M1 muscarinic receptors in rat brain [Messer, W.S., Jr., Abuh, Y.F., Liu, Y., Periyasamy, S., Ngur, D.O., Edgar, M.A., El-Assadi, A.A., Sbeih, S., Dunbar, P.G., Roknich, S., Rho, T., Fang, Z., Ojo, B., Zhang, H., Huzl, J.J., III, Nagy, P.I., 1997a. J. Med. Chem. 40, 1230-1246.] and improves memory function in rats with lesions of the basal forebrain cholinergic system. Moreover, CDD-0102 exhibits oral bioavailability, few side effects and low toxicity, and thus represents a viable candidate for clinical studies. Despite the development of functionally selective agonists such as xanomeline and CDD-0102, there is room for improvements in ligand affinity and selectivity. The high degree of amino acid homology within transmembrane domains has hindered the development of truly selective agonists. Site-directed mutagenesis, biochemical and molecular modeling studies have identified key amino acid residues such as Thr192 and Asn382 in the binding of agonist to M1 receptors [Huang, X.P., Nagy, P.I., Williams, F.E., Peseckis, S.M., Messer, W.S., Jr., 1999. Br. J. Pharmacol. 126, 735-745.]. Recent work has implicated residues at the top of transmembrane domain VI in the binding of muscarinic agonists and activation of M1 receptors [Huang, X.P., Williams, F.E., Peseckis, S.M., Messer, W.S., Jr., 1998. J. Pharmacol. Exp. Ther. 286, 1129-1139.]. Thus, residues such as Ser388 represent molecular targets for the further development of agonists with improved M1 receptor affinity, selectivity and activity.

Alzheimer Disease↗
PubMed2000

Refolding of rRNA exons enhances dissociation of the Tetrahymena intron.

Self-splicing of the Tetrahymena pre-rRNA is inhibited by a conserved rRNA hairpin P(-1) upstream of the 5' splice site. P(-1) inhibits self-splicing by competing with formation of the P1 splice site helix. Here we show that the P(-1) hairpin also enhances dissociation of the spliced products, which was monitored by native gel electrophoresis. Mutations that stabilize the rRNA hairpin increase the rate of dissociation approximately 10-fold, from 0.5 min(-1) for the wild-type RNA to approximately 4 min(-1) at 30 degrees C. Conversely, mutations or oligonucleotides that inhibit refolding of the exons and that stabilize the P1 helix decrease the rate of product release. The results suggest that refolding of products can be used to stimulate the turnover of ribozyme-catalyzed reactions. In the pre-rRNA, this conformational change helps shift the equilibrium of self-splicing toward the mature rRNA.

Animals↗
PubMed2000

Role of incipient angiogenesis in cancer metastasis.

Metastasis is the primary cause of mortality in cancer patients. Angiogenesis is intimately involved in metastasis at the site of entry of tumor cells into the vasculature and at the site of eventual metastasis growth. In this commentary, we review current paradigms regarding angiogenesis in metastatic sites. Recent discoveries challenge some of the existing paradigms. Significant prior data suggest that successful formation of metastases requires: 1) angiogenesis in the primary tumor site; 2) downregulation of cohesive molecules and tumor cell increased motility, resulting in invasion into neovessels; 3) tumor cell embolism; 4) arrest and attachment in capillary beds of distant organs; 5) extravasation and proliferation in the organ parenchyma; and 6) re-establishment of angiogenesis when the tumor reaches > 1-2 mm in size [1]. While most recent data largely confirm the aforementioned sequence of events, a few reports have revealed new knowledge about the earliest phases of angiogenesis of metastases. Of particular importance has been the ability to create tumor cell lines that are stably transfected with reporter genes, such as green fluorescence protein. With these tools it is now literally possible to monitor tumor formation from a single cell [2-7].

Animals↗
PubMed2000

Increased liposome-mediated gene transfer into haematopoietic cells grown in adhesion to stromal or fibroblast cell line monolayers.

We investigated transfection rates of CD34+ haematopoietic progenitor cells (HPC) or haematopoietic cell lines (TF-1, KG1a and K562) using the LacZ gene as a reporter and cationic liposomes. The transfection efficiency of CD34+ haematopoietic progenitor cells (HPC) or TF-1, KG1a and K562 grown in suspension is very low (average percentage of 0.013 for HPC and 0.03 for cell lines). Adhesion of HPC or cell lines to plates by immunological or physical methods significantly enhances transfection efficiency; however, the percentage of transfected cells still remained low. We found that adhesion of TF-1, KG1a and K562 HC to MS-5 stroma cells or NIH-3T3 fibroblast cells increased transfection efficiency. Under these conditions transfection is achieved in 11.2-25% (mean 18.30%) for the cell lines and 13.6% (range 8.2-24.2%) for CD34+ HPC. These results indicate that liposome-mediated transfection of HC is significantly increased when cells are grown in adherence to stroma or fibroblast monolayers.

3T3 Cells↗
PubMed2000

Engineering autogenous cartilage in the shape of a helix using an injectable hydrogel scaffold.

OBJECTIVE: Previous successful efforts to tissue engineer cartilage for an auricle have used an immunocompromised nude mouse xenograft model. Subsequent efforts in an immunocompetent autogenous animal model have been less successful because of an inflammatory response directed against the foreign scaffold polymer used to provide an auricular shape. We studied an alternative polymer material and surgical technique to engineer autogenous cartilage in the shape of a human ear helix using injectable hydrogel scaffolding, Pluronic F-127 (polyethylene oxide and polypropylene oxide). SUBJECT: Yorkshire swine. MATERIAL AND METHODS: Fresh autogenous chondrocytes were suspended in a biodegradable, biocompatible co-polymer hydrogel, Pluronic F-127, at a concentration of 3 x 10(7) cells/mL. To support the contour of the implant, a skin fold channel in the shape of the helix of a human ear was created in the skin in three sites on the ventral surface of the animal. The cell-hydrogel suspension was injected through the skin fold channel. For controls, injections were made into identical channels using either cells alone or the Pluronic F-127 without cells. After 10 weeks, the specimens were excised and examined both grossly and histologically. RESULTS: Grossly, all implants retained a helical-like shape. Excised specimens possessed flexible characteristics consistent with elastic cartilage. The specimens could be folded and twisted and on release of mechanical pressure would instantly return to the original shape. Histological evaluation of the implants using H&E, Safranin O, trichrome blue, and Verhoeff's stains demonstrated findings consistent with mature elastic cartilage. Control injection of hydrogel alone demonstrated no evidence of cartilage formation and control injection of chondrocytes alone showed evidence only of disassociated elastic cartilage. CONCLUSION: Injection of autologous porcine auricular chondrocytes suspended in a biodegradable, biocompatible hydrogel of Pluronic F-127 resulted in the formation of cartilage tissue in the approximate size and shape of a human ear helix. This preliminary method extends the concept of auricular tissue engineering from an immunocompromised xenograft animal model to an immunocompetent autologous animal model.

Animals↗
PubMed2000

Language hemispheric dominance in patients with congenital lesions of eloquent brain.

OBJECTIVE: In 90% of normal subjects, the left hemisphere is dominant for language function. We investigated whether congenital lesions of the left perisylvian regions altered cortical language representation in right-handed individuals. METHODS: Using functional magnetic resonance imaging, we studied language hemispheric dominance in five right-handed adult patients with congenitally acquired arteriovenous malformations (AVMs) originating from left hemispheric cortical language regions. The AVMs had not caused neurological symptoms during early development, but patients presented as adults with migraine, seizure, or minor hemorrhage. Results obtained from the AVM patients were contrasted to those from right-handed brain-injured stroke patients recovering from aphasia and to those from right-handed normal subjects. RESULTS: During silent picture naming and verb generation tasks, cortical language networks lateralized primarily to the right hemisphere in the AVM group, compared with the left hemisphere in the normal group. This right hemisphere-shifted language network in the AVM group exceeded the shifts toward right hemispheric dominance found in the stroke group. CONCLUSION: Patients with AVMs affecting the left perisylvian regions recruited the right hemisphere into language processing networks during early development, presumably in response to congenitally aberrant circulation. This early right hemisphere recruitment in the AVM patients exceeded the similar process in the brains of stroke patients whose left cortical language networks were damaged in adulthood. Our data provide evidence of effective plasticity in the developing human brain compared with the mature brain response to injury. Knowledge of cortical language representation should assist presurgical planning in patients with developmental anomalies affecting apparently language-dominant brain regions.

Adult↗
PubMed2000

Effect of 32/67 kDa laminin-binding protein antibody on mouse embryo implantation.

Mouse embryo implantation depends on the complex interaction between the embryo trophoblast cells and the uterine environment, which deposits an extracellular matrix with abundant amounts of laminin. Intrauterine injection and blastocyst or ectoplacental cone culture models were used to study the effect of 32/67 kDa laminin-binding protein antibody on mouse embryo implantation in vivo and in vitro. Intrauterine injection of 32/67 kDa laminin-binding protein antibody (0.4 mg in 1 ml Ham's F-10 medium, 5 microl per mouse) into the left uterine horns of mice (n = 22) on day 3 of pregnancy inhibited embryo implantation significantly (P < 0.001) compared with the contralateral horns that had been injected with normal rabbit IgG. A continuous section study on day 5 after injection showed that the embryos in the control uteri implanted normally and developed healthily, but there were no embryos or the remaining embryos had disintegrated in the uteri injected with 32/67 kDa laminin-binding protein antibody. Blastocysts or ectoplacental cones were cultured in media containing 32/67 kDa laminin-binding protein antibody (0.2 mg ml(-1)) on laminin-coated dishes with normal rabbit IgG at the same concentration as in the controls. The 32/67 kDa laminin-binding protein had no effect on blastocyst or ectoplacental cone attachment, but prohibited the blastocyst or ectoplacental cone outgrowth and primary or secondary trophoblast giant cell migration. These results indicate that 32/67 kDa laminin-binding protein antibody blocked mouse embryo implantation by preventing embryo trophoblast cell invasion and migration through the uterine decidual basement membrane-like extracellular matrix which has a high laminin content.

Analysis of Variance↗
PubMed2000

Bispecific MAb aided liposomal drug delivery.

We have developed a new method for specifically delivering liposomal model drugs to tumor cells. Bispecific monoclonal antibodies (bsMAb) (174H.64 x anti-biotin) which can bind tumor-specific antigen and biotin were developed and characterized. Biotinylated stealth liposome loaded with model drug 99mTc-DTPA can bind to the biotin-binding arm of bsMAb. This targeted liposomal delivery strategy was tested in mouse KLN-205 squamous carcinoma model. bsMAbs were administered 24h in advance into tumor allograft bearing mice, which allow them to bind to tumor cells through the anti-tumor binding arm. After clearance of circulating bsMAb, biotinylated stealth liposomes were introduced to specifically bind to the tumor sites where bsMAb localized earlier. The results show that pretargeted bsMAb can enhance liposomal drug targeting by four times, 3.61% dose/g vs. 0.89% dose/g. This bsMAb/liposome strategy show the broad possibilities of selective delivery of cytotoxic drugs or genes to the specific targets.

Animals↗
PubMed2000

Elevated levels of urine angiostatin and plasminogen/plasmin in cancer patients.

Previously, a specific angiogenesis inhibitor, angiostatin, discovered in urine and serum of tumor-bearing mice, was reported to potently block tumor growth and metastasis in animal models. Detection of angiostatin and its precursor proteins in urine from cancer patients has not been reported. Now, we report the development of an antibody-based analysis system that allows us to detect angiostatin and plasminogen/plasmin (Pgn/plasmin) in the urine of cancer patients. The detection system is a combination of a novel lysine-ELISA assay and Western immunoblot analysis using a specific antibody to human angiostatin and Pgn/plasmin. High levels of Pgn/plasmin were detected in the urine from various cancer patients, whereas healthy individuals showed relatively low levels of urine Pgn/plasmin. Of interest, angiostatin is detectable in urine samples of patients with various cancers, including acute lymphoblastic leukemia, suggesting that angiogenesis may play an important role in the development and progression of leukemia. Our data for the first time show that angiostatin and Pgn/plasmin are present at relatively high levels in the urine of human cancer patients. Detection of urine angiostatin in cancer patients helps us not only to understand the role of this angiogenesis inhibitor in cancer development and progression but also allows us to develop tools of cancer diagnosis and prognosis. Thus angiostatin has both therapeutic and diagnostic implications in cancer disease.

Adolescent↗
PubMed2000

[Catastrophic pulmonary vasoconstriction associated with protamine reversal of heparin].

Administration of protamine intravenously to neutralize the anticoagulant effects of heparin may be associated with hypotension. These adverse cardiovascular responses to protamine fall into three distinct types: transient hypotension related to rapid drug administration; anaphylactic responses: and catastrophic pulmonary vasoconstriction. We recently observed three patients who had catastrophic pulmonary vasoconstriction, which were treated with the assist circulation and intraaortic balloon pumping. The two patients were survived except one who was dead due to the cerebral ischemic damage which was introduced by delayed establishment of circulatory assist device. We conclude that meticulous longstanding observation of the hemodynamic condition is important after administration of protamine under the unremoved cannulations.

Aged↗
PubMed2000

An antigenic threshold for maintaining human immunodeficiency virus type 1-specific cytotoxic T lymphocytes.

BACKGROUND: Using the lymphocytic choriomeningitis virus (LCMV) model in mice, a number of studies show that memory cytotoxic T-lymphocyte (CTL) responses are maintained in the presence of continuous antigenic stimulation. Yet, other groups found that memory CTL specific for LCMV could last for a lifetime in mice without viral antigens. Thus, the extent to which an antigen is required for the maintenance of virus-specific CTL remains controversial. In humans, very few studies have been conducted to investigate the relationship between the quantity of antigen and the magnitude of CTL responses. MATERIALS AND METHODS: We quantified CTL precursors (CTLp) using a limiting-dilution analysis (LDA) and CTL effectors (CTLe) using a new Major Histocompatibility Complex (MHC) class I tetramer technology in six long-term nonprogressors (LTNPs) with human immunodeficiency virus type-1 (HIV-1) infection, as well as in eight patients whose viral loads were well suppressed by antiretroviral therapy. The viremia levels in these patients were measured using an reverse transcription polymerase chain reaction (RT-PCR) assay. The proviral DNA load in peripheral blood mononuclear cell (PBMC) was also measured by PCR in four LTNPs. RESULTS: The LTNPs had high levels of HIV-1-specific memory CTLp and CTLe, while maintaining a low plasma viral load. Despite also having low viral loads, patients whose plasma viremia was well-suppressed by effective therapy had low levels of CTLe. CONCLUSIONS: Our findings suggest that a complex, rather than a monotonic, relationship exists between CTL levels and HIV-1 viremia, including what appears to be an antigenic threshold for the maintenance of CTL at a measurable level. Under conditions of "antigen excess,", CTLe levels correlate inversely with viral load. On the other hand, under conditions that are "antigen limited," the correlation appears to be direct.

Adult↗