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1.
Antioxidants (Basel) ; 8(9)2019 Sep 18.
Article in English | MEDLINE | ID: mdl-31540452

ABSTRACT

Reactive Oxygen Species (ROS) and Reactive Nitrogen Species (RNS) have been proposed as universal signaling molecules in plant stress responses. There are a growing number of studies suggesting that hydrogen sulfide (H2S) or Reactive Sulfur Species (RSS) are also involved in plant abiotic as well as biotic stress responses. However, it is still a matter of debate as to how plants utilize those RSS in their signaling cascades. Here, we demonstrate that d-cysteine is a novel candidate for bridging our gap in understanding. In the genus of the tiny water-floating fern Azolla, a rapid root abscission occurs in response to a wide variety of environmental stimuli as well as chemical inducers. We tested five H2S chemical donors, Na2S, GYY4137, 5a, 8l, and 8o, and found that 5a showed a significant abscission activity. Root abscission also occurred with the polysulfides Na2S2, Na2S3, and Na2S4. Rapid root abscission comparable to other known chemical inducers was observed in the presence of d-cysteine, whereas l-cysteine showed no effect. We suggest that d-cysteine is a physiologically relevant substrate to induce root abscission in the water fern Azolla.

2.
Bone Marrow Transplant ; 45(2): 363-9, 2010 Feb.
Article in English | MEDLINE | ID: mdl-19525985

ABSTRACT

The interactions between chemokines and their receptors may have an important role in initiating GVHD after allogeneic hematopoietic SCT (allo-HSCT). CCL25 and CCR9 are unique because they are exclusively expressed in epithelial cells and in Peyer's patches of the small intestine. We focused on rs12721497 (G926A), one of the non-synonymous single nucleotide polymorphisms (SNPs) in the CCR9 gene, and analyzed the SNP of donors in 167 consecutive patients who received allo-HSCT from an HLA-identical sibling donor. Genotypes were tested for associations with acute and chronic GVHD in each organ and transplant outcome. Multivariate analyses showed that the genotype 926AG was significantly associated with the incidence of acute stage > or =2 skin GVHD (hazard ratio: 3.2; 95% confidence interval (95% CI): 1.1-9.1; P=0.032) and chronic skin GVHD (hazard ratio: 4.1; 95% CI: 1.1-15; P=0.036), but not with GVHD in other organs or with relapse, non-relapse mortality or OS. To clarify the functional differences between genotypes, each SNP in retroviral vectors was transfected into Jurkat cells. In chemotaxis assays, the 926G transfectant showed greater response to CCL25 than the 926A transfectant. In conclusion, more active homing of CCR9-926AG T cells to Peyer's patches may produce changes in Ag presentation and result in increased incidence of skin GVHD.


Subject(s)
Graft vs Host Disease/genetics , Hematopoietic Stem Cell Transplantation/adverse effects , Receptors, CCR/genetics , Adolescent , Adult , Chemotaxis, Leukocyte , Female , Graft vs Host Disease/epidemiology , Humans , Incidence , Jurkat Cells/physiology , Male , Middle Aged , Polymorphism, Single Nucleotide , Skin Diseases/epidemiology , Skin Diseases/etiology , Tissue Donors , Treatment Outcome
3.
Haemophilia ; 14(5): 1088-93, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18540891

ABSTRACT

Female carriers of haemophilia B are usually asymptomatic; however, the disease resulting from different pathophysiological mechanisms has rarely been documented in females. In this study, we investigated the mechanisms responsible for haemophilia B in fraternal female twins. We sequenced the factor IX gene (F9) of the propositus, her father, a severe haemophilia B patient and the other family members. X chromosome inactivation was assessed by the methylation-sensitive HpaII-PCR assay using X-linked polymorphisms in human phosphoglycerate kinase 1 gene (PGK1) and glutamate receptor ionotropic AMPA 3 gene (GRIA3). The twins were found to be heterozygotes with a nonsense mutation (p.Arg384X) inherited from their father. The propositus, more severely affected twin, exhibited a significantly higher percentage of inactivation in the maternally derived X chromosome carrying a normal F9. The other twin also showed a skewed maternal X inactivation, resulting in a patient with mild haemophilia B. Thus, the degree of skewing of maternal X inactivation is closely correlated with the coagulation parameters and the clinical phenotypes of the twins. Furthermore, we identified a crossing-over in the Xq25-26 region of the maternal X chromosome of the more severely affected twin. This crossing-over was absent in the other twin, consistent with their fraternal state. Differently skewed X inactivation in the fraternal female twins might cause moderately severe and mild haemophilia B phenotypes, respectively.


Subject(s)
Diseases in Twins/genetics , Hemophilia B/genetics , Twins, Dizygotic/genetics , X Chromosome Inactivation , Blotting, Southern/methods , Factor IX/genetics , Female , Haplotypes , Humans , Infant , Mutation, Missense , Pedigree , Polymerase Chain Reaction/methods
4.
Haemophilia ; 14(3): 556-63, 2008 May.
Article in English | MEDLINE | ID: mdl-18397285

ABSTRACT

Type 2A von Willebrand disease (VWD) is characterized by decreased platelet-dependent function of von Willebrand factor (VWF); this in turn is associated with an absence of high-molecular-weight multimers. Sequence analysis of the VWF gene from two unrelated type 2A VWD patients showed an identical, novel, heterozygous T-->G transversion at nucleotide 4508, resulting in the substitution of L1503R in the VWF A2 domain. This substitution, which was not found in 60 unrelated normal individuals, was introduced into a full-length VWF cDNA and subsequently expressed in 293T cells. Only trace amount of the mutant VWF protein was secreted but most of the same was retained in 293T cells. Co-transfection experiment of both wild-type and mutant plasmids indicated the dominant-negative mechanism of disease development; as more of mutant DNA was transfected, VWF secretion was impaired in the media, whereas more of VWF was stored in the cell lysates. Molecular dynamic simulations of structural changes induced by L1503R indicated that the mean value of all-atom root-mean-squared-deviation was shifted from those with wild type or another mutation L1503Q that has been reported to be a group II mutation, which is susceptible to ADAMTS13 proteolysis. Protein instability of L1503R may be responsible for its intracellular retention and perhaps the larger VWF multimers, containing more mutant VWF subunits, are likely to be mal-processed and retained within the cell.


Subject(s)
Molecular Biology , Mutation/genetics , von Willebrand Diseases/genetics , von Willebrand Factor/genetics , Adolescent , Amino Acid Substitution/genetics , DNA Mutational Analysis , Deamino Arginine Vasopressin/therapeutic use , Epistaxis/drug therapy , Exons/genetics , Female , Gene Expression , Hemostasis/drug effects , Hemostasis/genetics , Humans , Male , Middle Aged , Models, Molecular , Platelet Adhesiveness/physiology , Polymerase Chain Reaction , Recombinant Proteins , Structure-Activity Relationship , Transfection , von Willebrand Diseases/physiopathology , von Willebrand Factor/biosynthesis
6.
Leukemia ; 21(1): 136-42, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17039228

ABSTRACT

The cellular components of the hematopoietic stem cell niche have been gradually identified. However, the niche for malignant hematopoiesis remains to be elucidated. Here, using human leukemia cells, which could be transplanted to immunodeficient mice, we studied the in vivo homing, proliferation and survival sites by immunohistopathology, compared with the corresponding sites for cord blood CD34(+) (CBCD34(+)) cells. The human leukemia cells initially localized on the surface of osteoblasts in the epiphysial region, and expanded to the inner vascular and diaphysial regions within 4 weeks. The percentage of CD34(+) leukemia cells in the bone marrow was transiently increased up to 50%. In vivo 5-bromo-2'-deoxyuridine labeling revealed that the epiphysis was the most active site for leukemia cell proliferation. CBCD34(+) cells showed the similar pattern of homing and proliferation to leukemia cells. After high-dose administration of cytosine-1-beta-D-arabinofuranoside, residual leukemia cells were localized in the perivascular endothelium as well as in contact with the trabecular endosteum. These findings suggest that xenotransplantation into immunodeficient mice provides a useful model to study the leukemia niche.


Subject(s)
Leukemia/pathology , Animals , Antigens, CD34 , Arabinonucleosides/pharmacology , Bromodeoxyuridine , Cell Movement , Cell Proliferation , Cell Survival , Cord Blood Stem Cell Transplantation , Hematopoietic Stem Cells/pathology , Humans , Leukocyte Common Antigens , Mice , Mice, Inbred NOD , Mice, SCID , Neoplasm Transplantation , Tumor Cells, Cultured
7.
Parasite ; 13(3): 193-200, 2006 Sep.
Article in English | MEDLINE | ID: mdl-17007210

ABSTRACT

A new onchocercid species, Loxodontofilaria caprini n. sp. (Filarioidea: Nematoda), found in subcutaneous tissues of 37 (33%) of 112 serows (Noemorhedus crispus) examined in Japan, is described. The female worm had the characteristics of Loxodontofilaria, e.g., the large body size, well-developed esophagus with a shallow buccal cavity, and the long tail with three caudal lappets. The male worm of the new species, which was first described in the genus, had unequal length of spicules, 10 pairs of pre- and post-caudal papillae, and three terminal caudal lappets. Deirids were present in both sexes. Among four species of the genus loxodontofiloria: one from the hippopotamus and three from the Elepantidae, L. caprini n. sp. appears close to L. asiatica Bain, Baker & Chabaud, 1982, a subcutaneous parasite of Elephas indicus in Myanmar (Burma). However, L. caprini n. sp. is distinct from L. asiatica in that the Japanese female worm has an esophagus half as long and the microfilariae also half as long with a coiled posterior. The microfilariae were found in the skin of serows. The new parasite appears to clearly illustrate a major event in the evolution of onchocercids: the host-switching. This might have occurred on the Eurasian continent, where elephantids and the lineage of rupicaprines diversified during the Pliocene-Pleistocene, or in Japan, into which some of these hosts migrated.


Subject(s)
Filariasis/veterinary , Filarioidea/anatomy & histology , Filarioidea/classification , Phylogeny , Ruminants/parasitology , Animals , Biological Evolution , Elephants/parasitology , Female , Filariasis/epidemiology , Filariasis/parasitology , Filarioidea/isolation & purification , Goats/parasitology , Host-Parasite Interactions , Japan , Male , Sex Characteristics , Species Specificity
8.
J Thromb Haemost ; 4(1): 177-85, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16409467

ABSTRACT

BACKGROUND: We previously reported that the targeted disruption of murine antithrombin (AT) gene resulted in embryonic lethality before 16.5 gestational days (gd) because of severe cardiac and hepatic thrombosis. OBJECTIVE AND METHODS: To investigate the influences of lowered tissue factor (TF) activity upon hypercoagulation of AT-/- embryos, we crossed AT+/- with low TF (mTF-/- hTF+) mice to yield homozygous AT-deficient mice with the extremely low TF activity, that is expressed from the inserted human TF mini gene. RESULTS: AT-/- embryos either with 50% TF (AT-/- mTF+/- hTF+) or with low (approximately 1% TF, AT-/- mTF-/- hTF+) were not born, although the survival was prolonged until 18.5 gd. In both genotypes, histological examination showed disseminated thrombosis in hepatic sinusoidal space or in the portal veins, suggesting that the thrombogenesis caused loss of hepatic blood flow. As in original AT-/-, AT-/- mTF+/- hTF+ showed subcutaneous (s.c.) bleeding and also suffered from the myocardial degeneration apparently because of coronary thrombus formation. However, AT-/- mTF-/- hTF+ had no skin hemorrhage and the thrombosis and degeneration were completely abolished in the heart. Myocardium of adult low TF mice had exhibited fibrosis secondary to hemorrhage; however, it was significantly decreased in low TF mice with AT+/-. CONCLUSIONS: Our current model suggests that, in the heart, TF plays an important role in the thrombogenesis and it counterbalances AT-dependent anticoagulation. AT may be a potent anticoagulant during mice development and the activation and subsequent regulation of TF-procoagulant activity take place differently between the liver and the heart. These differences appear to point to local regulatory mechanisms in murine hemostasis.


Subject(s)
Antithrombin III/physiology , Thromboplastin/physiology , Thrombosis/etiology , Animals , Antithrombin III/genetics , Budd-Chiari Syndrome/blood , Budd-Chiari Syndrome/etiology , Coronary Thrombosis/blood , Coronary Thrombosis/etiology , Embryo, Mammalian , Hemorrhage/etiology , Hemostasis , Humans , Liver/metabolism , Mice , Mice, Knockout , Mice, Transgenic , Myocardium/metabolism , Myocardium/pathology , Thromboplastin/deficiency , Thrombosis/blood , Thrombosis/mortality
9.
Parasitol Int ; 54(3): 195-9, 2005 Sep.
Article in English | MEDLINE | ID: mdl-15936981

ABSTRACT

DNA sequences from a portion of the mitochondrial COI gene were used to clarify phylogenetic relationships among Japanese species in the genus Cercopithifilaria. Sequences were determined from seven Japanese species, five (C. shohoi, C. multicauda, C. minuta, C. tumidicervicata and C. bulboidea) from the serow (Capricornis crispus F. Bovidae) and two (C. longa and C. crassa) from the sika deer (Cervus nippon nippon F. Cervidae). No base substitutions were observed between C. bulboidea and C. longa, suggesting that recent host switching of a lineage of C. bulboidea between bovid and cervid hosts gave rise to C. longa. In phylogenetic trees inferred using a variety of methods, the morphologically ancestral type, C. bulboidea, appeared as a derived species. C. multicauda was found to be basal in the analyses. It seems therefore that C. multicauda is the most primitive out of the seven species.


Subject(s)
Antelopes/parasitology , Deer/parasitology , Filariasis/veterinary , Filarioidea/classification , Filarioidea/genetics , Phylogeny , Animals , DNA, Helminth/analysis , DNA, Mitochondrial/analysis , Electron Transport Complex IV/genetics , Filariasis/parasitology , Filarioidea/isolation & purification , Filarioidea/physiology , Host-Parasite Interactions , Japan , Mitochondria/enzymology , Molecular Sequence Data , Sequence Analysis, DNA , Species Specificity
10.
Interv Neuroradiol ; 10 Suppl 2: 41-7, 2004 Dec 24.
Article in English | MEDLINE | ID: mdl-20587248

ABSTRACT

SUMMARY: One hundred and seventy patients with ruptured cerebral aneurysms were treated by coil embolization from September 1997 to December 2002. After January 2000, coil embolization was selected as the first-choice treatment for ruptured aneurysms. During this period, the authors investigated the number of aborted cases, the number of complications, and how many patients could be treated by coil embolization according to the locations of ruptured cerebral aneurysms. One hundred and ninety-five sessions were performed on 170 patients, and 13 sessions (6.7%) were aborted mainly because of the difficulty of the approach and the wide necks of the aneurysms. In four patients, although procedural perforation and haemorrhage occurred, the outcome was good or excellent. Eight poorgrade patients experienced haemorrhage after coil embolization and seven patients died. The volume embolization ratios of small and large aneurysms were 27% and 21%, and the recanalization of small and large aneurysms occurred in 9% and 38% of patients, respectively. From January 2000 to December 2002, 119 (66%) of 180 ruptured cerebral aneurysms were treated by coil embolization. According to the location of aneurysms, 89% vertebrobasilar, 87% anterior cerebral, 65% internal carotid and 24% middle cerebral artery aneurysms could be treated by coil embolization. Because the tight packing of large aneurysms was difficult, the recanalization rate of large aneurysms was high. However, the results of small aneurysms were satisfactory. Almost 90% of vertebrobasilar and anterior cerebral artery aneurysms could be treated by coil embolization.

11.
Br J Dermatol ; 148(4): 799-803, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12752142

ABSTRACT

We report a patient with melorheostosis in whom increased procollagen alpha1(I) mRNA expression and alpha1(I), alpha2(I) and alpha1(III) collagen secretion were observed in dermal fibroblasts obtained from a skin biopsy overlying the involved bone. The patient was a 53-year-old man with melorheostosis lesions over the left knee joint. Multiple pigmented macules were present on the medial aspect of the lower left leg. Hyperpigmentation of the basal keratinocytes, thick-walled vessels in the reticular dermis, and proliferation of normal-appearing collagen around the hair follicles were observed histologically.


Subject(s)
Hyperpigmentation/metabolism , Leg Dermatoses/metabolism , Melorheostosis/metabolism , Procollagen/biosynthesis , Skin/metabolism , Fibroblasts/metabolism , Gene Expression , Humans , Hyperpigmentation/pathology , Leg Dermatoses/pathology , Male , Middle Aged , Procollagen/genetics , RNA, Messenger/genetics , Skin/pathology
12.
Parasite ; 9(4): 293-304, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12514943

ABSTRACT

Twelve of the 17 Cervus nippon nippon deer from Kyushu Island, Japan, that we examined were infected with one or two Cercopithifilaria species. C. longa n. sp. adults were in the subcutaneous tissues of limbs and the abdomen, and C. crassa n. sp. adults were in the skin, mainly in the anterior part of the back; the distribution of the dermal microfilariae generally matched that of the adult worms. The two new species were assigned to the group of primitive Cercopithifilaria species that parasitize ruminants (bavids and cervids), but the new species could readily be distinguished from others morphologically. C. longa was more primitive and resembled C. bulboidea, one of the five species from the serow Capricornis crispus, a Japanese member of the Caprinae, and species from Bovidae in Africa. C. crassa had a thick body and large spicules like C. rugosicauda from Capreolus capreolus in Europe, the only previously known Cercopithifilaria species from cervids, but it also had one or two hypertrophied pairs of caudal papillae, an unusual character found so far only in Japanese parasites. Among the 12 species known from ruminants, four are African, one is European and more highly evolved, and seven are Japanese, with some being primitive and some more evolved. The great diversity of Cercopithifilaria species in the two wild ruminants that live in Japan seems to have resulted from local speciation, which occurred during the Pleistocene, from a primitive form of the C. longa type derived from Eurasiatic ancestors, which has disappeared or, more probably, not yet been discovered.


Subject(s)
Cattle Diseases/parasitology , Deer/parasitology , Filariasis/veterinary , Filarioidea/classification , Goat Diseases/parasitology , Animals , Animals, Wild , Cattle , Female , Filariasis/parasitology , Filarioidea/anatomy & histology , Goats , Japan , Male
13.
Blood ; 98(10): 2973-9, 2001 Nov 15.
Article in English | MEDLINE | ID: mdl-11698279

ABSTRACT

Some families affected by von Willebrand disease type 1 show high penetrance with exceptionally low von Willebrand factor (VWF) levels. Previously, a mutation associated with this dominant phenotype, Cys1149Arg, was found to decrease the secretion of coexpressed normal VWF, and the mutation was proposed to cause intracellular retention of pro-VWF heterodimers. To demonstrate heterodimer formation, a model was developed in which subunits could be distinguished immunologically and by size. Recombinant VWF lacking domain A1 (dA1), A3 (dA3), or both (dA13) was secreted efficiently as a full range of multimers. Cotransfection of Cys1149Arg and dA13 resulted in the secretion of multimeric VWF containing about 250 kd (Cys1149Arg) and about 210 kd (dA13). Cell lysates contained pro-VWF forms of Cys1149Arg and dA13. Immunoprecipitation with an antidomain A1 antibody recovered both subunits in heterodimers, and subunit ratios were consistent with random dimerization. Similar results were obtained for cotransfection of Cys1149Arg and dA1. Normal VWF has a Cys1149-Cys1169 intrachain bond. When cotransfected with normal VWF, Cys1149Arg or the double mutant Cys1149Arg+Cys1169Ser caused a similar decrease in VWF secretion, suggesting that an unpaired Cys1169 does not explain the intracellular retention of Cys1149Arg. VWF Cys1149Arg was not secreted from BHK cells but was degraded intracellularly within about 4 hours, and the proteasome inhibitor lactacystin delayed its clearance more than 16 hours. Thus, dominant von Willebrand disease type 1 may be caused by heterodimerization of mutant and normal subunits in the endoplasmic reticulum followed by proteasomal degradation in the cytoplasm. A similar dominant negative mechanism could cause quantitative deficiencies of other multisubunit proteins.


Subject(s)
Amino Acid Substitution , Genes, Dominant , Mutation, Missense , von Willebrand Diseases/genetics , von Willebrand Factor/genetics , Animals , COS Cells , Cell Line , Chlorocebus aethiops , Cricetinae , Cysteine/chemistry , Cysteine Endopeptidases/metabolism , Cystine/chemistry , Dimerization , Endoplasmic Reticulum/metabolism , Humans , Intracellular Fluid/metabolism , Mesocricetus , Models, Genetic , Multienzyme Complexes/metabolism , Point Mutation , Proteasome Endopeptidase Complex , Protein Structure, Tertiary , Sequence Deletion , Transfection , von Willebrand Diseases/classification , von Willebrand Diseases/metabolism , von Willebrand Factor/chemistry , von Willebrand Factor/metabolism
14.
Parasite ; 8(3): 197-213, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11584750

ABSTRACT

The Japanese serow, Capricornis crispus (Bovidae, Caprinae, Rupicaprini), is parasitized by five Cercopithifilaria species: C. shohoi, recently described, and reexamined in this paper, C. multicauda n. sp., C. minuta n. sp., C. tumidicervicata n. sp., and C. bulboidea n. sp. Coinfections are frequent. The location (skin or subcutaneous regions) in the host of adult worms differed between the species, as did many morphological characters of both adults and microfilariae. The location (limbs, trunk, etc.) in the host of adult worms and dermal microfilariae seemed to differ depending on the species. Male and female worms of the same species had similar head shapes, buccal capsules, and, in four species, swellings in the anterior region of the body (because of the presence of a giant ventral pseudocoelomocyte). The Cercopithifilaria spp. from C. crispus were related to the primitive forms of the genus, parasites of Bovidae and Cervidae, presently recorded in Africa and Europe. C. bulboidea was particularly close to the most primitive species, C. ruandae and C. dermicola, in Africa, with the pairs of caudal papillae numbered 8 and 9 being distant from each other, but the species also had several specialized characters. Like C. rugosicauda in a European cervid, the four other species had pairs 8 and 9 close to each other; they reflect an evolutionary trend (hypertrophy of pair 6, and reduction and posterior migration of pair 7) that suggests diversification in the host.


Subject(s)
Filarioidea/classification , Goats/parasitology , Animals , Ecosystem , Female , Filariasis/parasitology , Filariasis/veterinary , Filarioidea/isolation & purification , Filarioidea/ultrastructure , Geography , Goat Diseases/parasitology , Japan , Male , Microscopy, Electron, Scanning
15.
Epidemiol Infect ; 126(1): 153-6, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11293676

ABSTRACT

The prevalence of parapoxvirus infection was examined in free-ranging wild ruminants in Japan, Japanese serow (Capricornis crispus) and Japanese deer (Cervus nippon centralis), in 1996-9. We collected a total of 151 serum samples from 101 Japanese serows and 50 Japanese deer and tested for antibodies against parapoxvirus by an enzyme-linked immunosorbent assay and an agar gel immunodiffusion test. Overall seroprevalences among Japanese serows were 5/25 (20.0%) in 1996, 4/14 (28.6%) in 1997, 5/32 (15.6%) in 1998 and 2/30 (6.7%) in 1999, respectively. The seroprevalence increased with age but was not affected by sex. No antibodies were detected from any of 50 serum samples taken from Japanese deer. Our results in this study suggest that parapoxvirus infection is widespread among the population of Japanese serows, however, Japanese deer appear to be still free of the disease.


Subject(s)
Animals, Wild , Antibodies, Viral/blood , Deer , Parapoxvirus/immunology , Poxviridae Infections/veterinary , Ruminants , Age Factors , Animals , Enzyme-Linked Immunosorbent Assay/veterinary , Female , Immunodiffusion/veterinary , Japan/epidemiology , Male , Parapoxvirus/classification , Parapoxvirus/isolation & purification , Poxviridae Infections/epidemiology , Seroepidemiologic Studies
16.
J Biol Chem ; 275(33): 25585-94, 2000 Aug 18.
Article in English | MEDLINE | ID: mdl-10831592

ABSTRACT

von Willebrand factor (VWF) is a multimeric glycoprotein that is required for normal hemostasis. After translocation into the endoplasmic reticulum, proVWF subunits dimerize through disulfide bonds between their C-terminal cystine knot-like (CK) domains. CK domains are characterized by six conserved cysteines. Disulfide bonds between cysteines 2 and 5 and between cysteines 3 and 6 define a ring that is penetrated by a disulfide bond between cysteines 1 and 4. Dimerization often is mediated by additional cysteines that differ among CK domain subfamilies. When expressed in a baculovirus system, recombinant VWF CK domains (residues 1957-2050) were secreted as dimers that were converted to monomers by selective reduction and alkylation of three unconserved cysteine residues: Cys(2008), Cys(2010), and Cys(2048). By partial reduction and alkylation, chemical and proteolytic digestion, mass spectrometry, and amino acid sequencing, the remaining intrachain disulfide bonds were characterized: Cys(1961)-Cys(2011) (), Cys(1987)-Cys(2041) (), Cys(1991)-Cys(2043) (), and Cys(1976)-Cys(2025). The mutation C2008A or C2010A prevented dimerization, whereas the mutation C2048A did not. Symmetry considerations and molecular modeling based on the structure of transforming growth factor-beta suggest that one or three of residues Cys(2008), Cys(2010), and Cys(2048) in each subunit mediate the covalent dimerization of proVWF.


Subject(s)
Cystine/chemistry , von Willebrand Factor/chemistry , Alanine/chemistry , Alkylation , Amino Acid Sequence , Animals , COS Cells , Chromatography, High Pressure Liquid , Computer Simulation , Cyanogen Bromide/pharmacology , Dimerization , Disulfides , Dithiothreitol/pharmacology , Ethylmaleimide/pharmacology , Glycosylation , Humans , Indicators and Reagents/pharmacology , Mass Spectrometry , Molecular Sequence Data , Mutagenesis, Site-Directed , Phosphines/pharmacology , Plasmids/metabolism , Protein Structure, Tertiary , Pyridines/pharmacology , Recombinant Proteins/chemistry , Sequence Analysis, Protein , Sequence Homology, Amino Acid , Sulfhydryl Reagents/pharmacology , Thermolysin/pharmacology , Time Factors , von Willebrand Factor/genetics
17.
Thromb Haemost ; 83(2): 239-43, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10739380

ABSTRACT

Factor VII is a vitamin K-dependent zymogen that plays a key role in the initiation of the extrinsic pathway. A severe factor VII deficiency was identified in a 45-year old male whose plasma factor VII antigen was less than 60 ng/ml and expressed 5.2% of normal factor VII activity. DNA sequence analysis of the patient's factor VII gene showed a thymidine to guanine transversion at nucleotide 10968 in exon VIII that results in a novel amino acid substitution of His348 to Gln. The patient was homozygous for this mutation, whereas some of his family members were heterozygous. Both wild type and mutant factor VII were transiently expressed in COS-1 cells. The level of secreted mutant factor VII antigen was only 11.0% of the level of wild type factor VII. In CHO cells stably transfected with the mutant factor VII, only 37.3% of the total labeled FVII was secreted into the conditioned media and the remainder was retained inside the cells. These data suggest this mutation leads to factor VII deficiency due to the impaired secretion of the molecule.


Subject(s)
Binding Sites/genetics , Factor VII Deficiency/genetics , Amino Acid Sequence , Amino Acid Substitution , Animals , Blood Coagulation Tests , CHO Cells , COS Cells , Cricetinae , DNA, Complementary , Factor VII/biosynthesis , Factor VII/chemistry , Factor VII/genetics , Factor VII Deficiency/blood , Family Health , Gene Expression , Hematemesis/genetics , Hemorrhage , Homozygote , Humans , Japan , Male , Middle Aged , Molecular Sequence Data , Mutation, Missense , Recombinant Proteins/biosynthesis , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Sequence Alignment , Sequence Analysis, DNA , Sulfur Radioisotopes , Transfection
18.
J Orthop Sci ; 5(6): 579-84, 2000.
Article in English | MEDLINE | ID: mdl-11180922

ABSTRACT

The effect of hyaluronan (hyaluronic acid; HA) on the healing of rabbit meniscus injured in the peripheral region was assessed. A longitudinal tear was created in the peripheral region of the medial meniscus in 20 mature New Zealand white rabbits. One week after surgery, HA was injected into the left knee joint once a week for 5 weeks (HA group), while saline was injected into the right knee (control group). Six and 12 weeks after surgery, gross morphology, histology, and biochemical evaluations were performed. On gross morphological examination, there was evidence of meniscal healing in both groups, but the healing rate of the HA group was significantly higher than that of the control group at 12 weeks. Histologically, meniscal healing started at the tibial portion of the meniscal injury at 6 weeks in both groups, then advanced in the direction of the femoral surface at 12 weeks in the HA group. Biochemically, water and glycosaminoglycan contents did not differ significantly between the two groups. Hyaluronan maintained the healing process of the injured menisci, especially in the femoral surface, up to 12 weeks after injury.


Subject(s)
Adjuvants, Immunologic/pharmacology , Hyaluronic Acid/pharmacology , Tibial Meniscus Injuries , Wound Healing/drug effects , Animals , Male , Rabbits
19.
J Orthop Sci ; 4(2): 127-34, 1999.
Article in English | MEDLINE | ID: mdl-10199990

ABSTRACT

We studied the effects of hyaluronan (HA) on chondrogenesis in periosteal grafts in rabbit knees to elucidate the effects of this agent in the repair of articular cartilage. Large full-thickness defects of the articular cartilage were created in the anteromedial part of the femoral articular surface of bilateral knee joints. Periosteal grafts were then harvested and sutured onto the defects. HA was injected in the right knee immediately after the operation and then once a week for 4 weeks (HA group). The same volume of saline was injected in the left knee in the control group. The animals were killed 2, 5, 8, and 12 weeks after the operation. Macroscopic and histological findings of the regenerated tissue were evaluated with a semiquantitative histological grading system. The total histological scores of the HA group were better than those in the control group at each time examination point. At 12 weeks, in particular, the scores for surface regularity and integration to adjacent articular cartilage were significantly better in the HA group than in the control group (P < 0.05). No significant differences were observed between the two groups in regard to the area healed (%). HA may have beneficial effects on the repair of large full-thickness defects of the articular cartilage with autologous periosteal grafts.


Subject(s)
Adjuvants, Immunologic/pharmacology , Cartilage, Articular/pathology , Chondrogenesis/drug effects , Hyaluronic Acid/pharmacology , Periosteum/transplantation , Animals , Hindlimb/pathology , Male , Rabbits , Transplantation, Autologous
20.
Thromb Res ; 92(4): 181-7, 1998 Nov 15.
Article in English | MEDLINE | ID: mdl-9840027

ABSTRACT

We have been studying the molecular basis of protein C deficiency. In this study, we determined the molecular defects of protein C deficiency in 19 Japanese families by using a strategy combining polymerase chain reaction (PCR) and single-strand conformational polymorphism (SSCP) analysis. We identified 10 missense mutations, 1 in-frame deletion, 1 frameshift deletion, 1 frameshift addition, and 1 splice site mutation, 5 of which were novel. From the results of genetic analysis of 67 Japanese families with protein C deficiency reported in this and previous studies, the recurrent defects including Phe139Val and Met365Ile substitutions and a Lys150 d letion, a G8857 deletion, and a splice site mutation of G3079A were only found in Japanese subjects and seemed to be a founder effect. In contrast, Arg169Trp, Arg286His, Val297Met, and Asp359Asn substitutions, all occurring at CG dinucleotides, were commonly observed in not only Japanese but also Western populations, indicating that these are hot spots for mutation in the protein C gene. These 9 recurrent molecular defects were found in 43 families in total, accounting 64% of Japanese families with protein C deficiency. In particular, the recurrent defects of Phe139Val, Arg169Trp, Va1297Met, and Met36-4Ile substitutions and a G8857 deletion were found in 33 families in total, accounting for 49% of Japanese families with protein C deficiency. For the identification of the genetic defect in Japanese patients with protein C deficiency, screening of these recurrent defects by using restriction enzyme cleavage is a rational method.


Subject(s)
Mutation , Protein C Deficiency/genetics , Exons/genetics , Humans , Japan , Pedigree , Polymerase Chain Reaction , Polymorphism, Single-Stranded Conformational
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