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1.
Phys Rev Lett ; 100(2): 022303, 2008 Jan 18.
Article in English | MEDLINE | ID: mdl-18232859

ABSTRACT

We show that the enhancement of the saturation scale in large nuclei relative to the proton is significantly influenced by the effects of quantum evolution and the impact parameter dependence of dipole cross sections in high energy QCD. We demonstrate that there is a strong A dependence in diffractive deeply inelastic scattering and discuss its sensitivity to the measurement of the recoil nucleus.

2.
EMBO J ; 20(17): 4762-73, 2001 Sep 03.
Article in English | MEDLINE | ID: mdl-11532940

ABSTRACT

Vascular endothelial growth factor receptor-3 (VEGFR-3/Flt4) binds two known members of the VEGF ligand family, VEGF-C and VEGF-D, and has a critical function in the remodelling of the primary capillary vasculature of midgestation embryos. Later during development, VEGFR-3 regulates the growth and maintenance of the lymphatic vessels. In the present study, we have isolated and cultured stable lineages of blood vascular and lymphatic endothelial cells from human primary microvascular endothelium by using antibodies against the extracellular domain of VEGFR-3. We show that VEGFR-3 stimulation alone protects the lymphatic endothelial cells from serum deprivation-induced apoptosis and induces their growth and migration. At least some of these signals are transduced via a protein kinase C-dependent activation of the p42/p44 MAPK signalling cascade and via a wortmannin-sensitive induction of Akt phosphorylation. These results define the critical role of VEGF-C/VEGFR-3 signalling in the growth and survival of lymphatic endothelial cells. The culture of isolated lymphatic endothelial cells should now allow further studies of the molecular properties of these cells.


Subject(s)
Apoptosis/physiology , Endothelial Growth Factors/pharmacology , Endothelial Growth Factors/physiology , Endothelium, Vascular/physiology , Endothelium/physiology , Lymphatic System/physiology , MAP Kinase Signaling System/physiology , Receptor Protein-Tyrosine Kinases/physiology , Receptors, Growth Factor/physiology , Apoptosis/drug effects , Biosensing Techniques , Capillaries/embryology , Capillaries/physiology , Cell Division , Cell Movement , Cell Survival , Cells, Cultured , Endothelium/cytology , Endothelium, Vascular/cytology , Enzyme Activation , Humans , Kinetics , Lymphatic System/cytology , Microcirculation/physiology , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3 , Mitogen-Activated Protein Kinases/metabolism , Protein Kinase C/metabolism , RNA, Messenger/genetics , Receptor Protein-Tyrosine Kinases/genetics , Receptors, Growth Factor/genetics , Receptors, Vascular Endothelial Growth Factor , Skin/blood supply , Umbilical Veins , Vascular Endothelial Growth Factor C , Vascular Endothelial Growth Factor D , Vascular Endothelial Growth Factor Receptor-3
3.
Int J Cancer ; 95(1): 29-33, 2001 Jan 20.
Article in English | MEDLINE | ID: mdl-11241307

ABSTRACT

Few data on the influence of lymphatic microvessel density (MVD) on survival in cancer are available since until recently there was no reliable immunohistological marker for lymphatic endothelium. Using an antibody staining podoplanin, a novel marker for lymphatic endothelium, lymphatic MVD in tissue samples of 85 patients with cervical cancer classification pT1b treated by radical hysterectomy was investigated. Survival was determined using univariate and multivariate analyses. Lymphatic MVD was also compared to MVD assessed by immunostaining against factor VIII-related antigen, which is considered a marker for blood vessels. Patients with >5 lymphatic microvessels/0.25 mm(2) field had significantly better overall survival (mean 91.8 months) than those with < or =5 lymphatic microvessels/field in univariate analysis (mean 113 months) (p = 0.0105, log-rank test). In multivariate analysis, lymphatic node involvement (p =0.0183), vessel infiltration (p =0.0158) and lymphatic MVD (p =0.0269) remained independent prognostic factors. No correlation between lymphatic MVD and various clinical and histopathological parameters was observed. Correlation between lymphatic MVD and MVD assessed by immunostaining against factor VIII was only weak (p = 0.004, r = 0.312, Spearman's coefficient of correlation). Our results suggest that increased lymphatic MVD is associated with favorable prognosis in early-stage cervical cancer.


Subject(s)
Lymph Nodes/pathology , Microcirculation/pathology , Uterine Cervical Neoplasms/diagnosis , Adenocarcinoma/blood supply , Adenocarcinoma/diagnosis , Adenocarcinoma/metabolism , Brachytherapy , Carcinoma, Adenosquamous/blood supply , Carcinoma, Adenosquamous/diagnosis , Carcinoma, Adenosquamous/metabolism , Carcinoma, Squamous Cell/blood supply , Carcinoma, Squamous Cell/diagnosis , Carcinoma, Squamous Cell/metabolism , Female , Humans , Immunohistochemistry , Lymph Nodes/blood supply , Lymph Nodes/metabolism , Lymphatic Metastasis , Membrane Glycoproteins/biosynthesis , Microcirculation/metabolism , Multivariate Analysis , Neoplasm Invasiveness , Prognosis , Time Factors , Uterine Cervical Neoplasms/blood supply , Uterine Cervical Neoplasms/metabolism , von Willebrand Factor/biosynthesis
4.
Clin Cancer Res ; 7(1): 93-7, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11205924

ABSTRACT

Lymphovascular space invasion was shown to play a key role in the progression of cervical cancer. Because of the absence of a specific marker for lymphatic vessels, earlier studies could not reliably distinguish between blood and lymphatic vessel invasion. By immunostaining for podoplanin, a novel marker for lymphatic endothelium, and for factor VIII-related antigen, we determined lymphatic and blood vessel invasion in tissue samples of 98 patients with cervical cancer pT1b treated by radical hysterectomy. Eleven (11.2%) specimens showed invasion of blood vessels, 20 (20.4%) showed invasion of lymphatic vessels, and 15 (15.3%) showed invasion of blood and lymphatic vessels. There was a strong association of lymphatic vessel invasion and lymph node involvement (P < 0.001). In univariate analysis, both blood and lymphatic vessel invasion failed to reach a statistically significant influence on overall survival, but a significant influence on disease-free survival was found (P = 0.0002 and P < 0.0001, respectively). In multivariate analysis of disease-free survival, only blood vessel invasion remained statistically significant (P = 0.0457). Lymphatic vessel invasion reached significance when lymph node status was excluded from the model (P = 0.0025). Both lymphatic vessel and blood vessel invasion occur frequently in early-stage cervical cancer. Determination of the vessel status may be of clinical importance because it signifies the risk of recurrent disease.


Subject(s)
Biomarkers/analysis , Lymphatic System/metabolism , Membrane Glycoproteins/metabolism , Neovascularization, Pathologic/metabolism , Uterine Cervical Neoplasms/blood supply , von Willebrand Factor/metabolism , Adult , Biopsy , Female , Humans , Hysterectomy , Immunoenzyme Techniques , Lymph Node Excision , Lymphatic Metastasis , Multivariate Analysis , Survival Analysis , Uterine Cervical Neoplasms/pathology , Uterine Cervical Neoplasms/surgery
5.
Anticancer Res ; 20(5A): 2981-5, 2000.
Article in English | MEDLINE | ID: mdl-11062711

ABSTRACT

BACKGROUND: The influence of lymphatic microvessel density (MVD) on survival in epithelial ovarian cancer is still unknown, owing to the fact that until recently no reliable immunohistologic markers for lymphatic endothelium were available. MATERIALS AND METHODS: By using a polyclonal antibody staining podoplanin, a novel marker for lymphatic endothelium, lymphatic MVD in tissue samples of 90 patients with epithelial ovarian cancer treated by radical surgery and chemotherapy was investigated. Survival analysis was performed using univariate and multivariate analysis. Furthermore, lymphatic MVD was compared to MVD assessed by CD34 immunostaining. RESULTS: Lymphatic MVD was significantly lower than CD34 MVD (p < 0.0001). There was no significant association between lymphatic MVD and various histological and clinical parameters. Lymphatic MVD had no influence on overall survival and disease free survival (p = 0.4627 and p = 0.4337, respectively; log-rank test). CONCLUSION: The formation of lymphatic vessels has no influence on the progression of epithelial ovarian cancer.


Subject(s)
Endothelium, Lymphatic/blood supply , Mesothelioma/blood supply , Ovarian Neoplasms/blood supply , Age Factors , Animals , Biomarkers , Endothelium, Lymphatic/pathology , Female , Follow-Up Studies , Humans , Membrane Glycoproteins/analysis , Mesothelioma/chemistry , Mesothelioma/classification , Mesothelioma/pathology , Microcirculation/pathology , Middle Aged , Neoplasm Staging , Ovarian Neoplasms/chemistry , Ovarian Neoplasms/classification , Ovarian Neoplasms/pathology , Prognosis , Rabbits , Recurrence
6.
Lab Invest ; 79(2): 243-51, 1999 Feb.
Article in English | MEDLINE | ID: mdl-10068212

ABSTRACT

Despite intensive research over the past decade, the exact lineage relationship of Kaposi's sarcoma (KS) tumor cells has not yet been settled. In the present study, we investigated the expression of two markers for lymphatic endothelial cells (EC), ie, vascular endothelial growth factor receptor-3 (VEGFR-3) and podoplanin, in AIDS and classic KS. Both markers were strongly expressed by cells lining irregular vascular spaces in early KS lesions and by tumor cells in advanced KS. Double-staining experiments by confocal laser microscopy established that VEGFR-3-positive and podoplanin-positive cell populations were identical and uniformly expressed CD31. By contrast, these cells were negative for CD45, CD68, and PAL-E, excluding their hemopoietic and blood vessel endothelial cell nature. Podoplanin expression in primary KS tumor lysates was confirmed by Western blot analysis. Both splice variants of VEGFR-3 were found in KS-tumor-derived RNA by RT-PCR. In contrast to KS tumor cells in situ, no expression of VEGFR-3 and podoplanin was detected in any of four KS-derived spindle cell cultures and in one KS-derived autonomously growing cell line (KS Y-1). Our findings that KS tumor cells express two lymphatic EC markers in situ strongly suggest that they are related to or even derived from the lymphatic EC lineage. Lack of these antigens on cultured cells derived from KS lesions indicates that they might not represent tumor cells that grow in tissue culture, but rather other cell types present in KS lesions.


Subject(s)
Lymphatic System/cytology , Lymphatic System/metabolism , Membrane Glycoproteins/metabolism , Receptor Protein-Tyrosine Kinases/metabolism , Receptors, Cell Surface/metabolism , Sarcoma, Kaposi/metabolism , Sarcoma, Kaposi/pathology , Blotting, Western , Cell Line , Endothelium/cytology , Endothelium/metabolism , Humans , RNA, Messenger/metabolism , Receptor Protein-Tyrosine Kinases/genetics , Receptors, Cell Surface/genetics , Tumor Cells, Cultured/metabolism , Vascular Endothelial Growth Factor Receptor-3
8.
Am J Pathol ; 154(2): 385-94, 1999 Feb.
Article in English | MEDLINE | ID: mdl-10027397

ABSTRACT

Angiosarcomas apparently derive from blood vessel endothelial cells; however, occasionally their histological features suggest mixed origin from blood and lymphatic endothelia. In the absence of specific positive markers for lymphatic endothelia the precise distinction between these components has not been possible. Here we provide evidence by light and electron microscopic immunohistochemistry that podoplanin, a approximately 38-kd membrane glycoprotein of podocytes, is specifically expressed in the endothelium of lymphatic capillaries, but not in the blood vasculature. In normal skin and kidney, podoplanin colocalized with vascular endothelial growth factor receptor-3, the only other lymphatic marker presently available. Complementary immunostaining of blood vessels was obtained with established endothelial markers (CD31, CD34, factor VIII-related antigen, and Ulex europaeus I lectin) as well as podocalyxin, another podocytic protein that is also localized in endothelia of blood vessels. Podoplanin specifically immunolabeled endothelia of benign tumorous lesions of undisputed lymphatic origin (lymphangiomas, hygromas) and was detected there as a 38-kd protein by immunoblotting. As paradigms of malignant vascular tumors, poorly differentiated (G3) common angiosarcomas (n = 8), epitheloid angiosarcomas (n = 3), and intestinal Kaposi's sarcomas (n = 5) were examined for their podoplanin content in relation to conventional endothelial markers. The relative number of tumor cells expressing podoplanin was estimated and, although the number of cases in this preliminary study was limited to 16, an apparent spectrum of podoplanin expression emerged that can be divided into a low-expression group in which 0-10% of tumor cells contained podoplanin, a moderate-expression group with 30-60% and a high-expression group with 70-100%. Ten of eleven angiosarcomas and all Kaposi's sarcomas showed mixed expression of both lymphatic and blood vascular endothelial phenotypes. By double labeling, most podoplanin-positive tumor cells coexpressed endothelial markers of blood vessels, whereas few tumor cells were positive for individual markers only. From these results we conclude that (1) podoplanin is a selective marker of lymphatic endothelium; (2) G3 angiosarcomas display a quantitative spectrum of podoplanin-expressing tumor cells; (3) in most angiosarcomas, a varying subset of tumor cells coexpresses podoplanin and endothelial markers of blood vessels; and (4) all endothelial cells of Kaposi's sarcomas expressed the lymphatic marker podoplanin.


Subject(s)
Endothelium, Lymphatic/metabolism , Endothelium, Vascular/metabolism , Hemangiosarcoma/metabolism , Membrane Glycoproteins/metabolism , Vascular Neoplasms/metabolism , Antigens, CD34/metabolism , Biomarkers, Tumor/analysis , Capillaries/metabolism , Capillaries/pathology , Cells, Cultured , Endothelium, Lymphatic/pathology , Endothelium, Vascular/pathology , Factor VIII/metabolism , Fluorescent Antibody Technique, Indirect , Hemangiosarcoma/blood supply , Hemangiosarcoma/pathology , Humans , Immunoenzyme Techniques , Membrane Glycoproteins/immunology , Platelet Endothelial Cell Adhesion Molecule-1/metabolism , Receptor Protein-Tyrosine Kinases/metabolism , Receptors, Cell Surface/metabolism , Sialoglycoproteins/metabolism , Vascular Endothelial Growth Factor Receptor-3 , Vascular Neoplasms/blood supply , Vascular Neoplasms/pathology
9.
Verh Dtsch Ges Pathol ; 83: 270-5, 1999.
Article in German | MEDLINE | ID: mdl-10714221

ABSTRACT

AIMS: Angiosarcomas apparently derive from endothelia of the blood vasculature, however occasionally their histologic features suggest mixed origin from blood and lymphatic endothelia. In the absence of specific positive markers for lymphatic endothelia the precise distinction between these components was not possible so far. Here we provide evidence that podoplanin, a approximately 38 kD membrane glycoprotein of podocytes is a specific marker of lymphatic endothelium that was used to identify the relative fraction of tumor cells with lymphatic or blood vascular endothelial phenotype in vascular tumors. METHODS: Podoplanin was localized in normal human skin and kidney cortex by immunohistochemistry on paraffin sections, double immunofluorescence on frozen sections with PAL-E, immunoelectron microscopy and by immunoblotting. 45 vascular tumors (29 benign lesions, 11 angiosarcomas and 5 gastrointestinal Kaposi's sarcomas) were evaluated for podoplanin expression. Complementary staining was obtained with established endothelial markers (CD 31, CD 34, Factor VIII related antigen, UEA I) and with podocalyxin, another podocytic protein mainly present in endothelia of blood vessels. RESULTS: In human tissues podoplanin is specifically expressed in the endothelium of lymphatics, but not in blood vasculature or in hemangiomas. This expression is preserved in endothelia of all benign lymphatic tumorous lesions and all Kaposi's sarcomas examined. By contrast 10 out of 11 G3 angiosarcomas contained only variable fractions of podoplanin-expressing tumor cells. Most tumor cells coexpressed podoplanin and markers of blood vessel phenotype. CONCLUSIONS: (1) Podoplanin is a selective marker of lymphatic endothelium; (2) G3 angiosarcomas display a quantitative spectrum of podoplanin-expressing tumor cells; (3) In the majority of angiosarcomas tumor cells coexpress podoplanin and endothelial markers of blood vessels; (4) All endothelial cells of Kaposi's sarcomas expressed the lymphatic marker podoplanin.


Subject(s)
Hemangiosarcoma/pathology , Lymphatic System/pathology , Membrane Glycoproteins/analysis , Biomarkers/analysis , Endothelium/pathology , Humans , Kidney Cortex/cytology , Reference Values , Sensitivity and Specificity , Skin/cytology
10.
Mutat Res ; 393(1-2): 165-73, 1997 Sep 18.
Article in English | MEDLINE | ID: mdl-9357574

ABSTRACT

The genotoxic properties of 2',2'-difluorodeoxycytidine (dFdC) were characterised using diploid, mortal low-passage fibroblasts (LPF cells) and the spontaneously transformed fibroblast cell line V79. In both cell types, incorporation of dFdC into the DNA led to an increase of DNA single-strand breaks evaluated by an in situ nick translation assay and to an accumulation of cells in the S-phase of the cell cycle. At concentrations below those leading to cell cycle arrest, dFdC neither induced sister chromatid exchange (SCE) nor structural chromosome aberrations in LPF cells, whereas V79 cells accumulated SCEs as well as chromosome breaks over a broad dose range. In LPF cells treated with dFdC, chromosomal alterations were detected by the micronucleus assay within a narrow concentration range, whereas in V79 cells, a dose-dependent increase in the appearance of micronuclei was seen up to cytotoxic concentrations. In addition, V79 cells went into apoptosis, as evaluated by nuclear fragmentation and condensation, whereas this phenomenon was not detectable in LPF cells.


Subject(s)
Antimetabolites, Antineoplastic/toxicity , Deoxycytidine/analogs & derivatives , Mutagens/toxicity , Apoptosis/drug effects , Cell Cycle/drug effects , Cell Division/drug effects , Cell Line, Transformed , Cells, Cultured , Chromosome Aberrations , DNA Damage , Deoxycytidine/toxicity , Humans , Micronucleus Tests , Sister Chromatid Exchange/drug effects , Gemcitabine
12.
J Exp Med ; 183(4): 1761-75, 1996 Apr 01.
Article in English | MEDLINE | ID: mdl-8666933

ABSTRACT

Common chimpanzees (Pan troglodytes) infected with hepatitis C virus (HCV) show a disease progression similar to that observed for human patients. Although most infected animals develop a chronic hepatitis, virus persistence is associated with an ongoing immune response, for which the beneficial or detrimental effects are uncertain. Lines of virus-specific cytotoxic CD8+ T lymphocytes (CTL) have been previously established from liver biopsies of two common chimpanzees chronically infected with HCV-1. The viral epitopes recognized by six lines of CTL have been defined using synthetic peptides and shown to consist of 8 to 9-residue peptides derived from various viral proteins. Five of the epitopes derive from sequences that vary among strains of HCV. The majority of the corresponding variant epitopes from different HCV strains were either recognized less efficiently or not at all by the CTL, suggesting their response may have limited potential for controlling replication of HCV variants. Complementary DNAs encoding class I alleles of the two common chimpanzees, Patr-A, -B, and -C were cloned, sequenced, and transfected individually into a class I-deficient human cell line. Analysis of peptide presentation by the class I transfectants to CTL identified the Patr class I allotypes that present the six epitopes defined here and an additional epitope defined previously. The assignment of epitopes to class I allotypes based upon analysis of the transfected cells correlates precisely with the segregation of antigen-presenting function within a panel of common chimpanzee cell lines and the expression of class I heavy chains as defined by isoelectric focusing. Five of the HCV-1 epitopes are presented by Patr-B allotypes, two epitopes are presented by a Patr-A allotype, and none is presented by Patr-C allotypes.


Subject(s)
Antigen Presentation , CD8-Positive T-Lymphocytes/immunology , Hepacivirus/immunology , Histocompatibility Antigens Class I/immunology , Pan troglodytes/immunology , T-Lymphocytes, Cytotoxic/immunology , Amino Acid Sequence , Animals , Chronic Disease , Epitopes/immunology , Hepatitis C Antigens/immunology , Liver/cytology , Liver/immunology , Molecular Sequence Data , Oligopeptides/immunology , Peptide Fragments/immunology , Sequence Homology, Amino Acid , Species Specificity
13.
J Exp Med ; 183(2): 663-8, 1996 Feb 01.
Article in English | MEDLINE | ID: mdl-8627179

ABSTRACT

A cytotoxic T lymphocyte (CTL) line, derived from the liver of a common chimpanzee (Pan troglodytes) with hepatitis C, specifically recognized a hepatitis C viral 9-mer peptide (KHP-DATYSR in single-letter amino acid code) bound by the major histocompatibility complex (MHC) class I molecule, Patr-A04. This same CTL line also recognized the identical peptide bound by a structurally different class I molecule, Papa-A06, derived from the separate chimpanzee species, Pan paniscus or pygmy chimpanzee. These class I allotypes differ by six amino acids but, in spite of the structural differences, share the same antigen-presenting function. This is the first observation of antigen presentation to a given T cell receptor by different MHC class I allotypes from separate species.


Subject(s)
Antigen Presentation , Hepatitis C Antigens/immunology , Histocompatibility Antigens Class I/immunology , Pan troglodytes/immunology , Peptides/immunology , Animals , B-Lymphocytes/cytology , B-Lymphocytes/immunology , Cell Line , Cytotoxicity, Immunologic , Histocompatibility Antigens Class I/genetics , Histocompatibility Antigens Class I/isolation & purification , Isoelectric Focusing , Pan troglodytes/classification , Pan troglodytes/genetics , Species Specificity , T-Lymphocytes, Cytotoxic/cytology , T-Lymphocytes, Cytotoxic/immunology
14.
Tissue Antigens ; 45(3): 177-87, 1995 Mar.
Article in English | MEDLINE | ID: mdl-7761977

ABSTRACT

Daudi, a lymphoblastoid B cell line derived from an African Burkitt lymphoma does not express HLA-A,B,C antigens at the cell surface. Although HLA-A,B,C heavy chains are made normally they do not assemble into functional molecules because beta 2-microglobulin is absent. Previous serological analysis of somatic cell hybrids indicated that the HLA haplotypes of Daudi encoded HLA-A1, A10(A26), B17, and B16(38) antigens. Here we describe the application of molecular methods: ARMS-PCR, cDNA cloning and sequencing, immunoprecipitation and gel electrophoresis, to define the class I genotype of the Daudi cell line which is HLA-A*0102, A*6601, B*5801, B*5802, Cw*0302 and Cw*0602. With the exception of the B38 antigen, which is not a product of the alleles defined, the genotype is consistent with the serological description. Two previously undiscovered alleles emerged from this analysis: A*0102 and B*5802. The A*0102 allele differs from A*0101 by 5 nucleotide substitutions within exon 2 where it has a motif shared with A*30 alleles; the B*5802 allele differs from B*5801 by 3 substitutions in exon 3 where it has a motif shared with B*14 alleles. Subtyping HLA-A1 alleles showed A*0102 was well represented amongst individuals typed serologically as A1 in an African population but was absent from caucasoids. B*5802 has been found in a second individual. Thus the novel A and B alleles are not specific to the Daudi tumor. Overall, this analysis of a single East African cell illustrates the power of molecular methods to define new class I HLA alleles in non-caucasoid populations.


Subject(s)
Genes, MHC Class I/genetics , HLA-A Antigens/genetics , HLA-B Antigens/genetics , Tumor Cells, Cultured/immunology , Africa, Eastern , Alleles , Base Sequence , Black People/genetics , DNA/blood , Gene Frequency , HLA-A Antigens/classification , HLA-B Antigens/classification , HLA-C Antigens/classification , HLA-C Antigens/genetics , Humans , Molecular Sequence Data , Polymerase Chain Reaction
15.
Proc Natl Acad Sci U S A ; 91(5): 1839-42, 1994 Mar 01.
Article in English | MEDLINE | ID: mdl-8127891

ABSTRACT

A protein binding to a minor-group human rhinovirus (HRV2) was purified from HeLa cell culture supernatant. The amino acid sequences of tryptic peptides showed identity with the human low density lipoprotein (LDL) receptor (LDLR). LDL and HRV2 mutually competed for binding sites on human fibroblasts. Cells down-regulated for LDLR expression yielded much less HRV2 upon infection than cells with up-regulated LDLR. Virus also bound to the large subunit of the alpha 2-macroglobulin receptor/LDLR-related protein (alpha 2MR/LRP). LDLR-deficient fibroblasts yielded considerably less virus in the presence of receptor-associated protein (RAP), providing evidence that alpha 2MR/LRP also acts as a minor group HRV receptor.


Subject(s)
Receptors, LDL/metabolism , Receptors, Virus/metabolism , Rhinovirus/metabolism , Amino Acid Sequence , Binding, Competitive , Cells, Cultured , Fibroblasts/metabolism , Fibroblasts/microbiology , HeLa Cells , Humans , Hyperlipoproteinemia Type II/metabolism , Hyperlipoproteinemia Type II/microbiology , Molecular Sequence Data , Peptide Fragments/genetics , Receptors, LDL/classification , Receptors, LDL/genetics , Receptors, Virus/genetics
16.
Biochemistry ; 32(29): 7581-8, 1993 Jul 27.
Article in English | MEDLINE | ID: mdl-8338854

ABSTRACT

A mammalian cell infected with a human rhinovirus or enterovirus has a much reduced capability to translate capped mRNAs (the host cell shutoff), while still allowing translation of uncapped viral RNA. Biochemical and genetic evidence suggests that the viral proteinase 2A induces cleavage of the eukaryotic initiation factor (eIF) 4 gamma (also known as p220) component of eIF-4 (formerly called eIF-4F). However, neither the mechanism underlying the specific proteolysis of eIF-4 gamma nor the influence of this cleavage on the translation of capped mRNAs has been clarified. Such studies have been hampered by a lack of large quantities of a purified 2A proteinase. Therefore, the mature proteinases 2A of human rhinovirus 2 and coxsackievirus B4 were expressed in soluble form in Escherichia coli. A four-step purification protocol was developed; 1 mg of highly purified 2A proteinase per gram wet weight of E. coli was obtained. Both enzymes cleaved directly eIF-4 gamma as part of the purified eIF-4 complex. Addition of HRV2 2A proteinase to HeLa cell cytoplasmic translation extracts resulted in eIF-4 gamma cleavage and drastically reduced the translation of capped mRNA; addition of purified eIF-4 restored translation to the initial level. However, translation of a reporter gene driven by the 5'-untranslated region of human rhinovirus 2 was translated 2-3-fold more efficiently in the presence of HRV2 2A proteinase.


Subject(s)
Cysteine Endopeptidases/metabolism , Peptide Initiation Factors/metabolism , Picornaviridae/enzymology , Protein Biosynthesis/drug effects , Viral Proteins , Amino Acid Sequence , Cysteine Endopeptidases/pharmacology , Escherichia coli/genetics , Eukaryotic Initiation Factor-4F , Gene Expression , HeLa Cells , Humans , Molecular Sequence Data , Peptide Initiation Factors/pharmacology , Peptides/chemistry , Peptides/metabolism , Plasmids , Recombinant Proteins/metabolism , Recombinant Proteins/pharmacology , Substrate Specificity , Transformation, Bacterial
17.
AJNR Am J Neuroradiol ; 12(2): 347-54, 1991.
Article in English | MEDLINE | ID: mdl-1902042

ABSTRACT

To test the value of currently proposed angiographic categorizations of vein of Galen malformations and a hypothesis regarding the causes of vein of Galen malformations and of accompanying hydrocephalus, as well as to assess the relative utility of MR imaging and CT in clinical evaluation, we reviewed the clinical and radiologic records of 34 patients with vein of Galen malformations. Patients were divided into two groups on the basis of the angiographic demonstration of either an arteriovenous malformation nidus or a direct arteriovenous fistula to the wall of the vein of Galen or one of its tributaries. Patients with such a nidus (n = 17) could be distinguished from those with arteriovenous fistulas alone (n = 17) on the basis of age at presentation (p less than .01) and presenting symptoms. Venous constraints, thought to be etiologically important, were identified in 31 of 34 patients. The presence or absence of hydrocephalus was explainable by mass effect in only 24 of 32 patients. In seven of 32 cases, no obvious mass effect was seen in the presence of hydrocephalus, but arteriographic evidence of venous hypertension was present in all patients with hydrocephalus. MR provided improved depiction of both arterial and venous anatomy as compared with CT. Parenchymal abnormalities were uncommon. No patients had subarachnoid hemorrhages. We conclude that MR is superior to CT in the clinical evaluation of vein of Galen malformations, that the angiographic finding of a nidus separates patients with vein of Galen malformations into clinical and therapeutically relevant groups, and that simple mass effect on the aqueduct is not an adequate explanation for all cases of hydrocephalus in patients with this disease.


Subject(s)
Cerebral Angiography , Cerebral Veins/abnormalities , Magnetic Resonance Imaging , Tomography, X-Ray Computed , Cerebral Veins/diagnostic imaging , Female , Humans , Infant , Infant, Newborn , Male , Retrospective Studies
18.
Radiology ; 178(1): 109-14, 1991 Jan.
Article in English | MEDLINE | ID: mdl-1984287

ABSTRACT

The distributions of the cerebral gray matter, the white matter, and the intracranial cerebrospinal fluid (CSF) were measured in 14 patients with Alzheimer disease (AD) and in 14 healthy control subjects. The measurements, derived from two specifically designed magnetic resonance inversion-recovery sequences, compensate for partial signal averaging. The percentage of the gray matter in the brains of AD patients (44.9% +/- 4.4) was significantly lower than in control subjects (50.2% +/- 3.2). The most significant reduction (P less than .001) occurred in the temporal lobes (13.8%) and a central region (12.8); the reduction in frontal lobe (11.2%) and occipital lobe (9.2%) was also statistically significant (P less than .01). There was an increase in the CSF volume in the temporal, occipital, and frontal regions; no region showed a significant difference in the white matter content. The findings of diffuse changes and temporal lobe involvement in AD are consistent with pathologic observations of cortical cell loss.


Subject(s)
Alzheimer Disease/diagnosis , Brain/pathology , Magnetic Resonance Imaging/methods , Aged , Alzheimer Disease/cerebrospinal fluid , Female , Humans , Image Processing, Computer-Assisted , Male , Temporal Lobe/pathology
19.
J Natl Med Assoc ; 82(9): 669-72, 1990 Sep.
Article in English | MEDLINE | ID: mdl-2213916

ABSTRACT

Corticosteroids are commonly used in the treatment of connective tissue diseases such as systemic lupus erythematosus. Although they are usually efficacious, osteoporosis leading to spine compression fractures is not uncommon. In this case report, we describe an elderly patient with systemic lupus erythematosus on long-term corticosteroid therapy who presented with symptoms of acute abdomen with minimal low back symptoms. No intraabdominal process was found by abdominal studies and exploratory laparotomy. Increased lower back symptoms led to further skeletal spine studies, which initially demonstrated a compression fracture at the twelfth thoracic (T12) vertebra. Later, a T8 and a fourth lumbar (L4) compression fracture were also found. Her abdominal and lower back symptoms resolved on conservative therapy. Although the rate of these occurrences are unknown, compression spine fractures should be considered in elderly patients presenting with acute abdomen after being on long-term corticosteroid therapy.


Subject(s)
Fractures, Spontaneous/complications , Intestinal Obstruction/etiology , Lumbar Vertebrae/injuries , Spinal Fractures/complications , Thoracic Vertebrae/injuries , Aged , Female , Fractures, Spontaneous/chemically induced , Humans , Lupus Erythematosus, Systemic/drug therapy , Prednisone/adverse effects , Prednisone/therapeutic use , Spinal Fractures/chemically induced , Time Factors
20.
Otolaryngol Pol ; 44(2): 135-8, 1990.
Article in Polish | MEDLINE | ID: mdl-2216506

ABSTRACT

The authors described a rare case of the middle ear tuberculosis in 4 years old child. It was the mastoiditis, which was operated upon. Two years without recurrency in observation.


Subject(s)
Mastoiditis/diagnosis , Otitis Media/diagnosis , Tuberculosis, Osteoarticular/diagnosis , Child, Preschool , Diagnosis, Differential , Humans , Male , Mastoiditis/surgery , Tuberculosis, Osteoarticular/surgery
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