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1.
Parasitol Res ; 99(6): 694-9, 2006 Nov.
Article in English | MEDLINE | ID: mdl-16738890

ABSTRACT

Anaplasma phagocytophilum is an obligate intracellular bacterium that is transmitted to humans through the bite of Ixodes spp. ticks, and causes a febrile disease known as human granulocytic anaplasmosis. The presence of A. phagocytophilum in Wisconsin white-tailed deer blood and in deer ticks was assessed using PCR and DNA sequencing. Sampling sites in the western part of the state (Buffalo County) and central region (Waushara, Waupaca, and Green Lake counties) were used. In Buffalo County, 5.6% of deer and 8.9% of ticks were infected. At Hartman Creek State Park (Waupaca County), 11.5% of ticks were infected, while the observed prevalence in deer from counties to the south of the park (Waushara and Green Lake) reached 19-26%. Based on 16S rRNA sequences, A. phagocytophilum strains associated and not associated with human infections were identified. Furthermore, two novel A. phagocytophilum variants were found in deer blood samples. Transmission of Lyme disease has been documented in both the Western and Central regions we sampled, and the presence of A. phagocytophilum in naturally occurring tick populations could present an additional risk of disease to humans that enter tick habitats.


Subject(s)
Anaplasma phagocytophilum/isolation & purification , Deer/microbiology , Ixodes/microbiology , Anaplasma phagocytophilum/classification , Anaplasma phagocytophilum/genetics , Animals , Base Sequence , Cytochromes b/genetics , DNA, Bacterial/genetics , DNA, Ribosomal/genetics , Deer/genetics , Genes, Mitochondrial , Humans , Molecular Sequence Data , Polymerase Chain Reaction , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Wisconsin
2.
Insect Biochem Mol Biol ; 31(10): 949-64, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11483431

ABSTRACT

In this report, we describe the structural and functional analyses of four acyl-CoA desaturase-encoding cDNAs that we isolated from RNA expressed in the pheromone gland of the corn earworm, Helicoverpa zea. We deduced the homology relationships of the encoded proteins, designated HzPGDs1, HzPGDs2, HzPGDs3 and HzFBDs, to each other and to previously described desaturases of the cabbage looper moth, Trichoplusia ni, the fly, Drosophila melanogaster, and other more distantly related organisms. We also isolated genomic DNA fragments of the four H. zea desaturase-encoding genes, determined the locations of introns present in them, and compared them to conserved intron positions in reported desaturase genes of other species. We measured the levels of the four desaturase mRNAs in H. zea pheromone glands and larval fat bodies by RT-PCR. We established the functional identities of the deduced proteins HzPGDs1 and HzPGDs2, encoded by the two desaturase mRNAs that are differentially and abundantly expressed in pheromone glands of sexually mature adult H. zea females, by functional expression of their encoding cDNAs in a desaturase-deficient mutant, ole1, of the yeast Saccharomyces cerevisiae. We compared the unique unsaturated fatty acid profiles of HzPGDs1- and HzPGDs2-expressing transformants to those of strains expressing previously described Delta11 and Delta9 desaturases of T. ni.


Subject(s)
Fatty Acid Desaturases/genetics , Moths/enzymology , Amino Acid Sequence , Animals , Base Sequence , DNA Probes , DNA, Complementary , Fat Body/metabolism , Fatty Acid Desaturases/classification , Genes, Insect , Humans , Larva/metabolism , Molecular Sequence Data , Moths/genetics , Pheromones , Polymerase Chain Reaction/methods , RNA, Messenger/metabolism , Sequence Analysis, DNA
3.
Insect Biochem Mol Biol ; 29(5): 435-43, 1999 May.
Article in English | MEDLINE | ID: mdl-10380655

ABSTRACT

Acyl-CoA delta 9-desaturases play essential roles in fatty acid metabolism and the regulation of cell membrane fluidity. In this research, a cDNA sequence was obtained from Trichoplusia ni adult fat body mRNA by using RT-PCR with degenerate primers based on other characterized delta 9-desaturase sequences. The remainder of the sequence was amplified using 3'- and 5'-RACE. A 1439 bp cDNA reconstructed from three overlapping PCR products contains an ORF encoding a 353-amino acids (aa) protein that shows clear homology (greater than 50% aa identity and greater than 65% aa similarity to characterized insect and vertebrate desaturases). The ORF of this cDNA was subcloned into an expression vector, which relieved the unsaturated fatty acid (UFA) auxotrophy of a desaturase-deficient yeast strain following genetic transformation. The newly characterized desaturase from T. ni produced fatty acids delta 9-16 and delta 9-18 in a 1:6 ratio, compared to a 5:1 ratio, respectively, with the yeast delta 9 desaturase. A Northern blot hybridization and a RT-PCR experiment showed that temporal and tissue-specific patterns of expression of the corresponding mRNA are distinct from those of the delta 11-desaturase mRNA present in the pheromone glands of adult females. Based on its homology to other desaturases, the widespread distribution of its corresponding mRNA in various tissues, and its functional assay, we conclude that this cDNA encodes the apoprotein corresponding to the desaturase component of the metabolic delta 9-desaturase complex of T. ni.


Subject(s)
Fatty Acid Desaturases/genetics , Moths/enzymology , Amino Acid Sequence , Animals , Base Sequence , Cloning, Molecular , DNA, Complementary , Fatty Acid Desaturases/metabolism , Fatty Acid Desaturases/physiology , Molecular Sequence Data , Moths/genetics , RNA, Messenger , Rats , Sequence Homology, Amino Acid , Stearoyl-CoA Desaturase , Tissue Distribution
4.
Proc Natl Acad Sci U S A ; 95(26): 15287-92, 1998 Dec 22.
Article in English | MEDLINE | ID: mdl-9860961

ABSTRACT

Desaturation of coenzyme-A esters of saturated fatty acids is a common feature of sex pheromone biosynthetic pathways in the Lepidoptera. The enzymes that catalyze this step share several biochemical properties with the ubiquitous acyl-CoA Delta9-desaturases of animals and fungi, suggesting a common ancestral origin. Unlike metabolic acyl-CoA Delta9-desaturases, pheromone desaturases have evolved unusual regio- and stereoselective activities that contribute to the remarkable diversity of chemical structures used as pheromones in this large taxonomic group. In this report, we describe the isolation of a cDNA encoding a pheromone gland desaturase from the cabbage looper moth, Trichoplusia ni, a species in which all unsaturated pheromone products are produced via a Delta11Z-desaturation mechanism. The largest ORF of the approximately 1,250-bp cDNA encodes a 349-aa apoprotein (PDesat-Tn Delta11Z) with a predicted molecular mass of 40,240 Da. Its hydrophobicity profile is similar overall to those of rat and yeast Delta9-desaturases, suggesting conserved transmembrane topology. A 182-aa core domain delimited by conserved histidine-rich motifs implicated in iron-binding and catalysis has 72 and 58% similarity (including conservative substitutions) to acyl-CoA Delta9Z-desaturases of rat and yeast, respectively. Northern blot analysis revealed an approximately 1,250-nt PDesat-Tn Delta11Z mRNA that is consistent with the spatial and temporal distribution of Delta11-desaturase enzyme activity. Genetic transformation of a desaturase-deficient strain of the yeast Saccharomyces cerevisiae with an expression plasmid encoding PDesat-Tn Delta11Z resulted in complementation of the strain's fatty acid auxotrophy and the production of Delta11Z-unsaturated fatty acids.


Subject(s)
Fatty Acid Desaturases/genetics , Moths/enzymology , Amino Acid Sequence , Animals , Cloning, Molecular , Conserved Sequence , DNA, Complementary , Endocrine Glands/enzymology , Fatty Acid Desaturases/biosynthesis , Fatty Acid Desaturases/chemistry , Genes, Insect , Molecular Sequence Data , Molecular Weight , Moths/genetics , Open Reading Frames , Pheromones/metabolism , Rats , Saccharomyces cerevisiae/enzymology , Sequence Alignment , Sequence Homology, Amino Acid
5.
Thromb Haemost ; 80(6): 912-8, 1998 Dec.
Article in English | MEDLINE | ID: mdl-9869160

ABSTRACT

OBJECTIVE: To assess the safety and efficacy of a fixed dose of recombinant activated factor VII (rFVIIa; NovoSeven) in the home setting for mild to moderately severe joint, muscle; and mucocutaneous bleeding episodes in patients with haemophilia A or B with inhibitors. DESIGN: Multicentre, open-label, single arm, phase III study of one year duration. METHODS; Patients or their caregivers administered up to three doses of rFVIIa (90 microg/kg i.v.) at 3 h intervals within 8 h of the onset of a mild to moderate bleeding episode. Once the subject considered that rFVIIa had been "effective" with regard to haemostasis (after 1-3 injections), one further (maintenance) dose of rFVIIa was administered. RESULTS: Of 60 patients enrolled, 56 experienced at least one bleed, and 46 completed the one year study. 614 of 877 bleeds (70%) were evaluable according to protocol definitions. Haemostasis was rated as "effective" in 92% (566/614) of evaluable bleeds after a mean of 2.2 injections. For successfully treated episodes, the time from onset of bleeding until administration of the first injection was 1.1+/-2.0 h (mean+/-SD). Twenty-four hours after initial successful response, haemostasis was reported as having been maintained in 95% of cases. Efficacy was comparable for muscle, joint and target joint, and mucocutaneous bleeding episodes. In an intent-to-treat analysis of all 877 bleeding events, efficacy outcomes were equivalent to the evaluable bleeds, with an effective response in 88% of treated episodes. Treatment-related adverse events occurred in 32 (3% of all) bleeding episodes and consisted of re-bleeds/new bleeds in more than 50% (18/32) of these events. A single episode of superficial thrombophlebitis was the only thrombotic complication encountered, and there were no patient withdrawals due to adverse events. Development of FVII(a) antibodies could not be detected, and hypersensitivity reactions to rFVIIa were not reported. CONCLUSION: rFVIIa is effective and well tolerated when used in the home setting to treat mild to moderate bleeding episodes in patients with haemophilia A or B with inhibitors.


Subject(s)
Factor IX/immunology , Factor VIII/immunology , Factor VIIa/therapeutic use , Hemophilia A/complications , Hemorrhage/drug therapy , Hemostatics/therapeutic use , Home Nursing , Isoantibodies/blood , Adolescent , Adult , Child , Child, Preschool , Drug Administration Schedule , Factor VIIa/administration & dosage , Factor VIIa/adverse effects , Female , Hemarthrosis/drug therapy , Hemarthrosis/etiology , Hemophilia A/immunology , Hemophilia A/therapy , Hemophilia B/complications , Hemophilia B/immunology , Hemophilia B/therapy , Hemorrhage/etiology , Hemostatics/administration & dosage , Hemostatics/adverse effects , Humans , Male , Middle Aged , Recombinant Fusion Proteins/administration & dosage , Recombinant Fusion Proteins/adverse effects , Recombinant Fusion Proteins/therapeutic use , Treatment Outcome
6.
J Clin Invest ; 100(9): 2276-85, 1997 Nov 01.
Article in English | MEDLINE | ID: mdl-9410905

ABSTRACT

Tissue factor (TF) is a transmembrane glycoprotein that initiates the coagulation cascade. Because of the potential role of TF in mediating arterial thrombosis, we have examined its expression in human aortic and coronary artery smooth muscle cells (SMC). TF mRNA and protein were induced in SMC by a variety of growth agonists. Exposure to PDGF AA or BB for 30 min provided all of the necessary signals for induction of TF mRNA and protein. This result was consistent with nuclear runoff analyses, demonstrating that PDGF-induced TF transcription occurred within 30 min. A newly developed assay involving binding of digoxigenin-labeled FVIIa (DigVIIa) and digoxigenin-labeled Factor X (DigX) was used to localize cellular TF. By light and confocal microscopy, prominent TF staining was seen in the perinuclear cytoplasm beginning 2 h after agonist treatment and persisting for 10-12 h. Surface TF activity, measured on SMC monolayers under flow conditions, increased transiently, peaking 4-6 h after agonist stimulation and returning to baseline within 16 h. Peak surface TF activity was only approximately 20% of total TF activity measured in cell lysates. Surface TF-blocking experiments demonstrated that the remaining TF was found as encrypted surface TF, and also in an intracellular pool. The relatively short-lived surface expression of TF may be critical for limiting the thrombotic potential of intact SMC exposed to growth factor stimulation. In contrast, the encrypted surface and intracellular pools may provide a rich source of TF under conditions associated with SMC damage, such as during atherosclerotic plaque rupture or balloon arterial injury.


Subject(s)
Muscle, Smooth, Vascular/metabolism , Platelet-Derived Growth Factor/pharmacology , Thromboplastin/metabolism , Aorta , Cell Compartmentation , Cells, Cultured , Factor VIIa/metabolism , Factor X/metabolism , Gene Expression/drug effects , Humans , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rheology , Thromboplastin/genetics , Transcription, Genetic/drug effects
7.
Thromb Haemost ; 76(5): 697-702, 1996 Nov.
Article in English | MEDLINE | ID: mdl-8950776

ABSTRACT

Tissue factor (TF) initiates coagulation and its expression in vascular smooth muscle cells (VSMC) likely plays a role in the propagation of arterial thrombosis. We report cloning the cDNA and proximal promoter region of the rat TF gene. While maintaining the general structure and organization of the TF molecule, there is a surprising divergence (approximately 18%) between the derived amino acid sequences of the rat and mouse TF. In contrast, there is striking similarity (90%) in the 5' untranslated regions. High levels of basal promoter activity were seen in rat VSMC with constructs containing 106 bp of sequence downstream from the putative transcription start site and 426 to 103 bp of upstream sequence. Deletion of the sequence from -103 to -79, containing a single SP1 site, removed virtually all of the basal and serum-induced activity. Removal of the NF kappa B site or two additional upstream SP1 sites had little effect on serum responsiveness. Removal of the 5' untranslated region abolished most of the basal activity of the TF promoter, suggesting that its high degree of conservation may be due to the presence of transcriptional elements critical for TF expression in rodent VSMC.


Subject(s)
Rats/genetics , Thromboplastin/genetics , Amino Acid Sequence , Animals , Base Sequence , Cells, Cultured , Cloning, Molecular , DNA, Complementary/genetics , Humans , Male , Molecular Sequence Data , Muscle, Smooth, Vascular/cytology , Mutagenesis, Site-Directed , Promoter Regions, Genetic , Rabbits , Rats, Sprague-Dawley , Sequence Alignment , Sequence Deletion , Sequence Homology , Species Specificity
8.
Lab Invest ; 73(4): 476-82, 1995 Oct.
Article in English | MEDLINE | ID: mdl-7474918

ABSTRACT

BACKGROUND: Atherosclerosis and arterial injury are characterized by vascular smooth muscle cell (VSMC) migration and growth and an increase in synthesis of extracellular matrix. Platelet-derived growth factor (PDGF) has been implicated in these processes. This study was designed to identify additional PDGF-regulated genes in VSMC. EXPERIMENTAL DESIGN: A cDNA library prepared from PDGF-stimulated rat aortic VSMC was screened by differential hybridization to identify clones representing PDGF-inducible genes. The time course of growth factor-induced changes in gene expression was examined by RNA blot hybridization. Assays of protein activity were also performed for selected gene products. RESULTS: Four PDGF-regulated cDNA clones were identified by DNA sequencing. These encoded the extracellular matrix proteins lysyl oxidase (LO), thrombospondin, and osteopontin and the intracellular enzyme lactate dehydrogenase (LDH). Levels of mRNA corresponding to all four genes were low in quiescent VSMC and were markedly induced by PDGF, angiotensin II, and 10% calf serum. The regulation of LO and LDH mRNA by these agonists in VSMC has not been previously reported. LO enzymatic activity in the culture media was increased by approximately equals to 700% after exposure to PDGF. In contrast, LDH activity was not increased by PDGF treatment. CONCLUSIONS: The induction of LO mRNA and its secretion by VSMC is an early event accompanying growth factor stimulation and may contribute to organization of the extracellular matrix.


Subject(s)
Membrane Glycoproteins/genetics , Muscle, Smooth, Vascular/chemistry , Platelet-Derived Growth Factor/pharmacology , Protein-Lysine 6-Oxidase/genetics , Sialoglycoproteins/genetics , Angiotensin II/pharmacology , Animals , Aorta, Thoracic/cytology , Base Sequence , Cells, Cultured , Cloning, Molecular , DNA, Complementary/analysis , DNA, Complementary/genetics , DNA, Complementary/metabolism , Extracellular Matrix/physiology , Gene Expression Regulation/drug effects , L-Lactate Dehydrogenase/analysis , L-Lactate Dehydrogenase/genetics , L-Lactate Dehydrogenase/physiology , Male , Membrane Glycoproteins/analysis , Membrane Glycoproteins/physiology , Molecular Sequence Data , Muscle, Smooth, Vascular/cytology , Muscle, Smooth, Vascular/enzymology , Osteopontin , Protein-Lysine 6-Oxidase/analysis , Protein-Lysine 6-Oxidase/physiology , RNA, Messenger/analysis , RNA, Messenger/genetics , Rats , Rats, Sprague-Dawley , Sialoglycoproteins/analysis , Sialoglycoproteins/physiology , Thrombospondins , Thymidine/metabolism , Time Factors , Tritium
10.
J Biol Chem ; 269(17): 13041-7, 1994 Apr 29.
Article in English | MEDLINE | ID: mdl-8175725

ABSTRACT

We have employed differential screening of a rat aortic smooth muscle cell cDNA library to isolate a cDNA clone, SM-20, whose nucleotide and deduced amino acid sequences are distinct from those reported previously. SM-20 encodes an mRNA of approximately 2.5-3.0 kilobase pairs which is present at low levels in quiescent vascular smooth muscle cells. SM-20 levels increase within 1 h of treatment with growth agonists (serum, platelet-derived growth factor, angiotensin II), isoproterenol, and forskolin. Cycloheximide induces high levels of SM-20 mRNA and superinduces it in the presence of serum, suggesting that the increase in SM-20 mRNA levels is not dependent on protein synthesis and is part of the primary response to growth agonists. SM-20 is expressed at high levels in tissues and cells derived from muscle (smooth, skeletal, and cardiac) and nerve (brain, PC12 cells) and is not expressed in 3T3 fibroblasts or rat 6 fibroblasts. SM-20 encodes a new member of the immediate early gene family and is unusual in that it is expressed in vascular smooth muscle, but not in fibroblasts.


Subject(s)
DNA-Binding Proteins , Growth Substances/physiology , Immediate-Early Proteins/genetics , Muscle, Smooth, Vascular/metabolism , 3T3 Cells , Amino Acid Sequence , Animals , Base Sequence , Cells, Cultured , Cloning, Molecular , DNA, Complementary , Hypoxia-Inducible Factor-Proline Dioxygenases , Immediate-Early Proteins/metabolism , Male , Mice , Molecular Sequence Data , Procollagen-Proline Dioxygenase , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley , Sequence Homology, Amino Acid
11.
J Pediatr Surg ; 29(2): 229-31, 1994 Feb.
Article in English | MEDLINE | ID: mdl-8176597

ABSTRACT

Extension of Wilms' tumor into the renal vein and vena cava complicates the operative treatment of a small but significant number of patients. Two children presented with Wilms' tumor and intracaval tumor extension. After biopsy, both children were given chemotherapy. In one case the tumor completely disappeared from the vena cava, and in the other the tumor regressed substantially, and proximal control became possible at the level of the infrahepatic vena cava. Both children then had an uneventful nephrectomy that was greatly simplified. We conclude that preoperative chemotherapy can induce resolution of intravascular tumor, and may be a useful option in cases of extension of Wilms' tumor into the vena cava.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Kidney Neoplasms/drug therapy , Kidney Neoplasms/pathology , Vena Cava, Inferior , Wilms Tumor/drug therapy , Wilms Tumor/pathology , Chemotherapy, Adjuvant , Child, Preschool , Dactinomycin/administration & dosage , Doxorubicin/administration & dosage , Female , Humans , Kidney Neoplasms/surgery , Male , Neoplasm Invasiveness , Premedication , Vincristine/administration & dosage , Wilms Tumor/surgery
12.
J Pediatr Surg ; 29(2): 235-6, 1994 Feb.
Article in English | MEDLINE | ID: mdl-7909844

ABSTRACT

Protein-S deficiency is a rare congenital disorder that results in a hypercoagulable state, typically presenting as recurrent venous thrombosis in adults. Few cases have been reported in children. A 2-year-old girl presented in septic shock. During laparotomy, ischemic necrosis of the intestine was noted, which extended from the gastroesophageal junction to the midjejunum. Total gastrectomy, pancreaticoduodenectomy , and partial resection of the small intestine were performed. She was left with 140 cm of distal small bowel, and had reconstruction with a single limb for the pancreaticojejunostomy, choledochojejunostomy, and esophagojejunostomy to preserve intestinal length. Postoperative evaluation eventually disclosed a previously unrecognized protein-S deficiency. The hypercoagulopathy of protein-S deficiency can be complicated by catastrophic thrombotic events that require surgery. This congenital disorder should be considered in any child who has an unexplained thrombotic episode, because failure to recognize protein-S deficiency may have potentially fatal consequences.


Subject(s)
Infarction/etiology , Intestines/blood supply , Metabolism, Inborn Errors/complications , Protein S Deficiency , Child, Preschool , Female , Gastrectomy , Humans , Infarction/pathology , Infarction/surgery , Intestines/pathology , Intestines/surgery , Necrosis , Pancreaticoduodenectomy , Shock, Septic/etiology
13.
J Pediatr Surg ; 28(8): 1023-5, 1993 Aug.
Article in English | MEDLINE | ID: mdl-8229589

ABSTRACT

Three patients with a new, pathologically distinct solid tumor of childhood have been treated recently. The disease is characterized by male predominance, adolescent onset, an extensive abdominal primary tumor, and aggressive metastases to regional lymph nodes, liver, and lung. Two patients presented with vague abdominal pain and the third with testicular pain. All three noted fatigue and malaise of less than two months' duration with minimal associated weight loss. Computed tomography (CT) scans of the abdomen and chest were obtained for initial preoperative staging, and then all three underwent surgical exploration. Widespread disease was found in each case. In no instance was complete tumor extirpation possible because of extensive peritoneal spread and lymphatic and hepatic metastases. Histologically, all three tumors consisted of round blue cells with a dense desmoplastic reaction and focal rhabdoid features. Immunohistochemical markers for epithelial, neural, and muscle elements were positive. Aggressive multidrug chemotherapeutic regimens were used in each case, and all three patients are alive and well but with known residual disease. We conclude that in cases of the desmoplastic round cell tumor of childhood, CT scans underestimate the extent of disease, and exploratory laparotomy is necessary for diagnosis and appropriate staging. Surgery is usually palliative because of extensive spread. Awareness of this newly recognized aggressive solid tumor of childhood is essential to define its natural history and guide the development of effective multidisciplinary therapeutic regimens.


Subject(s)
Carcinoma, Small Cell/surgery , Colonic Neoplasms/surgery , Pelvic Neoplasms/surgery , Adolescent , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Biomarkers, Tumor/analysis , Carcinoma, Small Cell/drug therapy , Carcinoma, Small Cell/pathology , Chemotherapy, Adjuvant , Child , Colonic Neoplasms/drug therapy , Colonic Neoplasms/pathology , Combined Modality Therapy , Humans , Lymph Node Excision , Lymph Nodes/pathology , Lymphatic Metastasis , Male , Pelvic Neoplasms/drug therapy , Pelvic Neoplasms/pathology
14.
J Clin Invest ; 91(2): 547-52, 1993 Feb.
Article in English | MEDLINE | ID: mdl-8432863

ABSTRACT

Tissue factor (TF) is a low molecular weight glycoprotein that initiates the clotting cascade and is considered to be a major regulator of coagulation, hemostasis, and thrombosis. TF is not expressed in the intima or media of normal adult blood vessels. Accordingly, it has been hypothesized that the initiation of intravascular coagulation may require the "induced" expression of TF in the vessel wall. We report that TF mRNA and protein are rapidly and markedly induced in early and late passaged vascular smooth muscle cells (VSMC) by growth factors (serum, platelet-derived growth factor, epidermal growth factor), vasoactive agonists (angiotensin II), and a clotting factor (alpha-thrombin). The induction of TF mRNA by these agents is dependent upon mobilization of intracellular Ca2+ and is blocked by Ca2+ chelation. In contrast to other growth factor-responsive genes, such as KC and c-fos, downregulation of protein kinase C activity by prolonged treatment with phorbol esters fails to block agonist-mediated TF induction. This raises the possibility that protein kinase C activation may not be necessary for TF mRNA induction in VSMC. VSMC may play a role in the generation or propagation of thrombus through the induction of TF, particularly in settings, such as those associated with acute vessel injury, where the endothelium is denuded and the VSMC are exposed to circulating blood.


Subject(s)
Calcium/metabolism , Muscle, Smooth, Vascular/metabolism , Protein Kinase C/metabolism , Thromboplastin/biosynthesis , Angiotensin II/pharmacology , Animals , Cells, Cultured , Enzyme Activation , Male , Platelet-Derived Growth Factor/pharmacology , RNA, Messenger/biosynthesis , Rats , Rats, Sprague-Dawley , Signal Transduction , Thrombin/pharmacology , Thromboplastin/genetics
15.
Leukemia ; 6(6): 535-40, 1992 Jun.
Article in English | MEDLINE | ID: mdl-1602792

ABSTRACT

The chromosomal rearrangements t(1;19)(q23;p13.3) and t(9;22) (q34;q11.2) are independent abnormalities commonly observed in the blast cells of children with acute lymphoblastic leukemia (ALL). We report three children whose leukemic cells contained both translocations at diagnosis. The patients, two males aged 3 and 8 years and a female aged 14 years, all presented with central nervous system involvement. One patient exhibited a pre-B leukemic phenotype (cytoplasmic immunoglobulin, cIg, positive), while two had an early pre-B phenotype (cIg negative). All three patients received radiotherapy and multiagent chemotherapy which included an epipodophyllotoxin in two patients. Two patients suffered relapses of ALL, in both cases with disappearance of t(1;19)-containing clones but persistence of t(9;22). The two patients who received an epipodophyllotoxin as part of their chemotherapeutic regimen both developed secondary myeloid leukemia with entirely new cytogenetic findings, including abnormalities of chromosome band 11q23. These patients are the first to be described with this unusual combination of cytogenetic abnormalities.


Subject(s)
Chromosomes, Human, Pair 19 , Chromosomes, Human, Pair 1 , Chromosomes, Human, Pair 22 , Chromosomes, Human, Pair 9 , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Translocation, Genetic , Adolescent , Child , Child, Preschool , Chromosomes, Human, Pair 11 , Combined Modality Therapy , Female , Humans , Karyotyping , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/therapy , Leukemia, Myeloid/genetics , Male , Neoplasms, Second Primary/genetics , Philadelphia Chromosome , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/genetics , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/therapy , Precursor Cell Lymphoblastic Leukemia-Lymphoma/therapy
16.
Plant Physiol ; 95(4): 1120-4, 1991 Apr.
Article in English | MEDLINE | ID: mdl-16668099

ABSTRACT

The activity of the Fe(3+) reductase of excised adventitious roots of Ficus benjamina L., grown in hydroponic culture without iron, was determined by a colorometric assay simplified by the use of a microplate reader. Reductase activity remained the same from pH 4.5 to 6.5 and decreased sharply above pH 6.5. Acetate buffer inhibited reduction. During early stages of root growth, excised roots did not exhibit Fe(3+) reductase activity. After several weeks and extensive root system development, Fe(3+) reduction still was not detectable in primary roots, but intermediate and high rates of reduction occurred in lateral and newly formed root clusters, respectively. Clustered roots only developed on plants grown at 0 or very low (<1 micromolar) iron. Microscopic examination revealed the root cluster to be composed of up to 30 lateral roots, usually less than 1 millimeter in diameter and 1 centimeter in length, that were completely covered with root hairs.

17.
Biochem Pharmacol ; 40(3): 615-9, 1990 Aug 01.
Article in English | MEDLINE | ID: mdl-2383288

ABSTRACT

The formycin analogs of nitrobenzylthioinosine and nitrobenzylthioguanosine were synthesized and evaluated as nucleoside transport inhibitors. These analogs have a potential therapeutic advantage over their parent compounds in that their C-nucleosidic linkages prevent them from being degraded to the immunosuppressive agents, 6-mercaptopurine and 6-thioguanine. 7-[(4-Nitrobenzyl)-thio]-3-(beta-D-ribofuranosyl)pyrazolo[4,3- d]pyrimidine (NBTF) and 5-amino-7-[(4-nitrobenzyl)thio]-3-(beta-D- ribofuranosyl)pyrazolo[4,3-d]pyrimidine (NBTGF) were inhibitors of nucleoside transport in human erythrocytes and HL-60 leukemia cells. The IC50 value for nitrobenzylthioinosine, NBTF and NBTGF with 10% erythrocyte suspensions were 18, 18 and 40 nM respectively. Specific binding studies with [3H]NBTF yielded a Kd of 3.4 nM with erythrocytes, approximately 10-fold higher than values reported for nitrobenzylthioinosine. NBTF and nitrobenzylthioinosine bound to HL-60 cells with Kd values of 8.1 and 0.81 nM respectively. The octanol/water partition coefficients of nitrobenzylthioinosine, NBTF and NBTGF were 3.5, 3.2, and 2.8 respectively. NBTF could be expected to be equipotent with nitrobenzylthioinosine in whole blood where inhibitor concentrations of 10(-7) to 10(-6) M are required in order to saturate erythrocytic binding sites; hence, it may exhibit the advantages inherent in a C-nucleoside.


Subject(s)
Nucleosides/metabolism , Thionucleosides/pharmacology , Adenosine/metabolism , Biological Transport/drug effects , Erythrocytes/metabolism , Humans , Leukemia, Promyelocytic, Acute/metabolism , Nucleosides/blood , Thioinosine/analogs & derivatives , Thioinosine/pharmacology , Thionucleosides/chemical synthesis , Thionucleosides/metabolism , Tumor Cells, Cultured
18.
Am J Dis Child ; 140(3): 238-41, 1986 Mar.
Article in English | MEDLINE | ID: mdl-2868651

ABSTRACT

Thyrotropin (TSH)-receptor autoantibodies were assessed by measurement of 125I-bTSH binding inhibition in 32 patients with juvenile-onset Graves' disease (one of whom was studied twice) and 16 normal control subjects. Thirteen (76.5%) of 17 thyrotoxic patients had significantly elevated TSH binding-inhibitory immunoglobulin (TBII) activity compared with eight (50%) of 16 patients who were in clinical remission and none of the control subjects. Mean TBII activity was significantly greater in thyrotoxic patients than in individuals in remission, except in one unusual patient in whom there was a discordance between TBII activity and in vitro thyroid-stimulatory activity. In eight euthyroid patients who were followed up for at least five months while not receiving treatment, assessment of TBII activity did not predict who would or would not suffer relapse at a later date. Thus, TBIIs are secreted in excess in juvenile Graves' disease, the titer decreasing as the disease remits. The TBII assay cannot be used as the sole predictor of when antithyroid medication can be withdrawn safely, however.


Subject(s)
Autoantibodies/analysis , Graves Disease/immunology , Receptors, Cell Surface/immunology , Thyrotropin/immunology , Adenylyl Cyclases/metabolism , Adolescent , Adult , Child , Female , Graves Disease/drug therapy , Humans , Immunoglobulin G/analysis , Immunoglobulins, Thyroid-Stimulating , Male , Receptors, Thyrotropin , Thyroid Gland/enzymology
19.
Plant Physiol ; 61(1): 101-3, 1978 Jan.
Article in English | MEDLINE | ID: mdl-16660218

ABSTRACT

On the basis of solubility, hydrolysis by glucoamylase (EC 3.2.1.3), and monomeric composition, starch appears to be the major glucose-containing, hot water-soluble polysaccharide that is labeled when germinated lily (Lilium longiflorum Thunb., cv. Ace) pollen is grown in the presence of myo-[2-(3)H]inositol, d-[R5,S5-(3)H]xylose, or l-[1-(14)C]arabinose.

20.
Plant Physiol ; 61(1): 89-95, 1978 Jan.
Article in English | MEDLINE | ID: mdl-16660245

ABSTRACT

The myo-inositol oxidation pathway was investigated in regard to its role as a source of carbon for products of hexose monophosphate metabolism in germinated pollen of Lilium longiflorum Thunb., cv. Ace. myo-[2-(14)]Inositol and d-[1-(14)C]glucuronate had similar distributions of radioactivity, contributing about three times more label to polysaccharide-bound glucose than myo-[2-(3)H]inositol. In the course of glucogenesis label from the latter appeared as tritiated water in the medium. This exchange could be enhanced by supplying d-[5R,5S-(3)H]xylose instead of myo-[2-(3)H]inositol. When the former was administered, [(3)H]glucose was the only labeled sugar residue found in polysaccharide products. The soluble constituents of d-[5R,5S-(3)H]xylose-labeled pollen contained no traces of labeled xylose despite massive uptake and utilization.l-[1-(14)C]- and l-[5-(14)C]Arabinose produced similar labeling patterns in germinated pollen including incorporation of arabinosyl units into pollen tube polysaccharides and substantial glucogenesis which led to utilization of arabinose for respiration and further incorporation of labeled glucosyl units into pollen tube polysaccharides.d-[5-(3)H]Galacturonate was rapidly taken up by germinated pollen but slowly utilized, without conversion to other sugars, for incorporation into pollen tube polysaccharides. l-[6-(14)C]Gulonate was not taken up by pollen.Results strongly support a scheme of conversion from myo-inositol to hexose monophosphate and subsequent products of glucose metabolism that involves the myo-inositol oxidation pathway.

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