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Zoki Abadi Harahap - One of the best experts on this subject based on the ideXlab platform.
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pengaruh Lysol terhadap pertumbuhan mycobacterium tuberculosis pada sputum bta positif sisa bahan pemeriksaan laboratorium bp 4 semarang
Jurnal Kesehatan, 2009Co-Authors: Ratih Horibi, Zoki Abadi HarahapAbstract:Abstrak Penyakit tuberculosis (TBC) disebabkan oleh kuman Mycobacterium tuberculosis atau Basil Tahan Asam (BTA). Kuman ini mudah menular dan penyakit yang ditimbulkannya dapat menyebabkan Kematian. Sputum dengan BTA positif adalah sangat in/ected dan harus ditangani dengan benar, agar infeksi tidak semakin menyebar Pemeriksaan sputum penderita tuberculosis. di Balai Pencegahan dan Pengobatan Penyakit Paru (BP 4) Semarang dilakukan dengan metoda sputum sewaktu, sputum pagi dan sputum sewaktu (SPS). Sputum sisa pemeril
Lysol dengan takaran yang ada aturan baku, untuk dibuang di septic tank dan dilaksanakan oleh tenaga non kesehatan. Dengan demikian perlu diteliti, apakah desinfeksi dengan Lysol tersebut sudah mampu membunuh BTA, sehingga penyebaran penyakit yang diakibatkan dapat dihindari. Â Tujuan penelitian , adalah mengelahui daya bunuh Lysol (konsentrasi I0%, 15%, dan 20%o) dengan kontak waktu 5, l0 dan 15 menit lerhadap BTA l+, 2+ dan 3+. Penelitian dilakukan dengan memberi perlakuan desinfeksi terhadap sputum BTA positif/ dengan Lysol konsentrasi l0 %, l5 o/o dan 20% Â selama Kontak waktu 5, l0 dan 15 menit. Selanjutnya sputum dikultur pada media Ogawa, diinkubasi pada suhu 3/C selama 6 hari Seminggu,untuk diamati pertumbuhan koloninya.sampel sebanyak iX3 Xg:8l dan 9 sebagai control. Penelitian dilakukan di Laboratorium Mikroskopis BP 4 Semarang. Analisa data disajikan dalam bentuk diskriptif dan diolah dengan uji ANOVA Untuk menguji normalitas digunakan uji Kolmogorov Smirnov Test dengan tingkat kepercayaan. 95% na Hasil penelitian menunjukan bahwa tidak ada pengaruh hambatan pertumbuhan BTA pada perlakuan desinfel Lysol konsentrasi l0%, 15 % dan 20 % pada kontak waktu 5, l0 dan l5 menit, pada BTA l+ dengan nilai P 0,228; pada BTA 2+ dengan nilai P 0,244 dan pada BTA 3 + dengan nilai P 0,667 Kesimpulannya adalah bahwa konsentrasi perlakuan desinfelui dengan Lysol l0%q l5%dan 20% pada kontak waktu 5, l0 dan I 5 menit tidak berpengaruh terhadap pertumbuhan BTA (perlakton desinfel tuberculosis, Lysol, Sputum -
pengaruh Lysol terhadap pertumbuhan mycobacterium tuberculosis pada sputum bta positif sisa bahan pemeriksaan laboratorium bp 4 semarang
None, 2009Co-Authors: Ratih Horibi, Zoki Abadi HarahapAbstract:Penyakit tuberculosis (TBC) disebabkan oleh kuman Mycobacterium tuberculosis atau Basil Tahan Asam (BTA). Kuman ini mudah menular dan penyakit yang ditimbulkannya dapat menyebabkan Kematian. Sputum dengan BTA positif adalah sangat in/ected dan harus ditangani dengan benar, agar infeksi tidak semakin menyebar Pemeriksaan sputum penderita tuberculosis. di Balai Pencegahan dan Pengobatan Penyakit Paru (BP 4) Semarang dilakukan dengan metoda sputum sewaktu, sputum pagi dan sputum sewaktu (SPS). Sputum sisa pemeril
Lysol dengan takaran yang ada aturan baku, untuk dibuang di septic tank dan dilaksanakan oleh tenaga non kesehatan. Dengan demikian perlu diteliti, apakah desinfeksi dengan Lysol tersebut sudah mampu membunuh BTA, sehingga penyebaran penyakit yang diakibatkan dapat dihindari. Tujuan penelitian, adalah mengelahui daya bunuh Lysol (konsentrasi I0%, 15%, dan 20%o) dengan kontak waktu 5, l0 dan 15 menit lerhadap BTA l+, 2+ dan 3+. Penelitian dilakukan dengan memberi perlakuan desinfeksi terhadap sputum BTA positif/ dengan Lysol konsentrasi l0 %, l5 o/o dan 20% selama Kontak waktu 5, l0 dan 15 menit. Selanjutnya sputum dikultur pada media Ogawa, diinkubasi pada suhu 3/C selama 6 hari Seminggu,untuk diamati pertumbuhan koloninya.sampel sebanyak iX3 Xg:8l dan 9 sebagai control. Penelitian dilakukan di Laboratorium Mikroskopis BP 4 Semarang. Analisa data disajikan dalam bentuk diskriptif dan diolah dengan uji ANOVA Untuk menguji normalitas digunakan uji Kolmogorov Smirnov Test dengan tingkat kepercayaan. 95% na Hasil penelitian menunjukan bahwa tidak ada pengaruh hambatan pertumbuhan BTA pada perlakuan desinfel Lysol konsentrasi l0%, 15 % dan 20 % pada kontak waktu 5, l0 dan l5 menit, pada BTA l+ dengan nilai P 0,228; pada BTA 2+ dengan nilai P 0,244 dan pada BTA 3 + dengan nilai P 0,667 Kesimpulannya adalah bahwa konsentrasi perlakuan desinfelui dengan Lysol l0%q l5%dan 20% pada kontak waktu 5, l0 dan I 5 menit tidak berpengaruh terhadap pertumbuhan BTA (perlakton desinfel
Ratih Horibi - One of the best experts on this subject based on the ideXlab platform.
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pengaruh Lysol terhadap pertumbuhan mycobacterium tuberculosis pada sputum bta positif sisa bahan pemeriksaan laboratorium bp 4 semarang
Jurnal Kesehatan, 2009Co-Authors: Ratih Horibi, Zoki Abadi HarahapAbstract:Abstrak Penyakit tuberculosis (TBC) disebabkan oleh kuman Mycobacterium tuberculosis atau Basil Tahan Asam (BTA). Kuman ini mudah menular dan penyakit yang ditimbulkannya dapat menyebabkan Kematian. Sputum dengan BTA positif adalah sangat in/ected dan harus ditangani dengan benar, agar infeksi tidak semakin menyebar Pemeriksaan sputum penderita tuberculosis. di Balai Pencegahan dan Pengobatan Penyakit Paru (BP 4) Semarang dilakukan dengan metoda sputum sewaktu, sputum pagi dan sputum sewaktu (SPS). Sputum sisa pemeril
Lysol dengan takaran yang ada aturan baku, untuk dibuang di septic tank dan dilaksanakan oleh tenaga non kesehatan. Dengan demikian perlu diteliti, apakah desinfeksi dengan Lysol tersebut sudah mampu membunuh BTA, sehingga penyebaran penyakit yang diakibatkan dapat dihindari. Â Tujuan penelitian , adalah mengelahui daya bunuh Lysol (konsentrasi I0%, 15%, dan 20%o) dengan kontak waktu 5, l0 dan 15 menit lerhadap BTA l+, 2+ dan 3+. Penelitian dilakukan dengan memberi perlakuan desinfeksi terhadap sputum BTA positif/ dengan Lysol konsentrasi l0 %, l5 o/o dan 20% Â selama Kontak waktu 5, l0 dan 15 menit. Selanjutnya sputum dikultur pada media Ogawa, diinkubasi pada suhu 3/C selama 6 hari Seminggu,untuk diamati pertumbuhan koloninya.sampel sebanyak iX3 Xg:8l dan 9 sebagai control. Penelitian dilakukan di Laboratorium Mikroskopis BP 4 Semarang. Analisa data disajikan dalam bentuk diskriptif dan diolah dengan uji ANOVA Untuk menguji normalitas digunakan uji Kolmogorov Smirnov Test dengan tingkat kepercayaan. 95% na Hasil penelitian menunjukan bahwa tidak ada pengaruh hambatan pertumbuhan BTA pada perlakuan desinfel Lysol konsentrasi l0%, 15 % dan 20 % pada kontak waktu 5, l0 dan l5 menit, pada BTA l+ dengan nilai P 0,228; pada BTA 2+ dengan nilai P 0,244 dan pada BTA 3 + dengan nilai P 0,667 Kesimpulannya adalah bahwa konsentrasi perlakuan desinfelui dengan Lysol l0%q l5%dan 20% pada kontak waktu 5, l0 dan I 5 menit tidak berpengaruh terhadap pertumbuhan BTA (perlakton desinfel tuberculosis, Lysol, Sputum -
pengaruh Lysol terhadap pertumbuhan mycobacterium tuberculosis pada sputum bta positif sisa bahan pemeriksaan laboratorium bp 4 semarang
None, 2009Co-Authors: Ratih Horibi, Zoki Abadi HarahapAbstract:Penyakit tuberculosis (TBC) disebabkan oleh kuman Mycobacterium tuberculosis atau Basil Tahan Asam (BTA). Kuman ini mudah menular dan penyakit yang ditimbulkannya dapat menyebabkan Kematian. Sputum dengan BTA positif adalah sangat in/ected dan harus ditangani dengan benar, agar infeksi tidak semakin menyebar Pemeriksaan sputum penderita tuberculosis. di Balai Pencegahan dan Pengobatan Penyakit Paru (BP 4) Semarang dilakukan dengan metoda sputum sewaktu, sputum pagi dan sputum sewaktu (SPS). Sputum sisa pemeril
Lysol dengan takaran yang ada aturan baku, untuk dibuang di septic tank dan dilaksanakan oleh tenaga non kesehatan. Dengan demikian perlu diteliti, apakah desinfeksi dengan Lysol tersebut sudah mampu membunuh BTA, sehingga penyebaran penyakit yang diakibatkan dapat dihindari. Tujuan penelitian, adalah mengelahui daya bunuh Lysol (konsentrasi I0%, 15%, dan 20%o) dengan kontak waktu 5, l0 dan 15 menit lerhadap BTA l+, 2+ dan 3+. Penelitian dilakukan dengan memberi perlakuan desinfeksi terhadap sputum BTA positif/ dengan Lysol konsentrasi l0 %, l5 o/o dan 20% selama Kontak waktu 5, l0 dan 15 menit. Selanjutnya sputum dikultur pada media Ogawa, diinkubasi pada suhu 3/C selama 6 hari Seminggu,untuk diamati pertumbuhan koloninya.sampel sebanyak iX3 Xg:8l dan 9 sebagai control. Penelitian dilakukan di Laboratorium Mikroskopis BP 4 Semarang. Analisa data disajikan dalam bentuk diskriptif dan diolah dengan uji ANOVA Untuk menguji normalitas digunakan uji Kolmogorov Smirnov Test dengan tingkat kepercayaan. 95% na Hasil penelitian menunjukan bahwa tidak ada pengaruh hambatan pertumbuhan BTA pada perlakuan desinfel Lysol konsentrasi l0%, 15 % dan 20 % pada kontak waktu 5, l0 dan l5 menit, pada BTA l+ dengan nilai P 0,228; pada BTA 2+ dengan nilai P 0,244 dan pada BTA 3 + dengan nilai P 0,667 Kesimpulannya adalah bahwa konsentrasi perlakuan desinfelui dengan Lysol l0%q l5%dan 20% pada kontak waktu 5, l0 dan I 5 menit tidak berpengaruh terhadap pertumbuhan BTA (perlakton desinfel
Philip C Trackman - One of the best experts on this subject based on the ideXlab platform.
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A Novel Function for Lysyl Oxidase in Pluripotent Mesenchymal Cell Proliferation and Relevance to Inflammation-Associated Osteopenia
PloS one, 2014Co-Authors: Roozbeh Khosravi, Katharine L. Sodek, Manish V. Bais, Debashree Saxena, Michael Faibish, Philip C TrackmanAbstract:Lysyl oxidase is a multifunctional enzyme required for collagen biosynthesis. Various growth factors regulate lysyl oxidase during osteoblast differentiation, subject to modulation by cytokines such as TNF-α in inflammatory osteopenic disorders including diabetic bone disease. Canonical Wnt signaling promotes osteoblast development. Here we investigated the effect of Wnt3a and TNF-α on lysyl oxidase expression in pluripotent C3H10T1/2 cells, bone marrow stromal cells, and committed osteoblasts. Lysyl oxidase was up-regulated by a transcriptional mechanism 3-fold in C3H10T1/2 cells, and 2.5-fold in bone marrow stromal cells. A putative functional TCF/LEF element was identified in the lysyl oxidase promoter. Interestingly, lysyl oxidase was not up-regulated in committed primary rat calvarial- or MC3T3-E1 osteoblasts. TNF-α down-regulated lysyl oxidase both in Wnt3a-treated and in non-treated C3H10T1/2 cells by a post-transcriptional mechanism mediated by miR203. Non-differentiated cells do not produce a collagen matrix; thus, a novel biological role for lysyl oxidase in pluripotent cells was investigated. Lysyl oxidase shRNAs effectively silenced lysyl oxidase expression, and suppressed the growth of C3H10T1/2 cells by 50%, and blocked osteoblast differentiation. We propose that interference with lysyl oxidase expression under excess inflammatory conditions such as those that occur in diabetes, osteoporosis, or rheumatoid arthritis can result in a diminished pool of pluripotent cells which ultimately contributes to osteopenia.
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collagen advanced glycation inhibits its discoidin domain receptor 2 ddr2 mediated induction of lysyl oxidase in osteoblasts
Bone, 2014Co-Authors: Roozbeh Khosravi, Katharine L. Sodek, Michael Faibish, Philip C TrackmanAbstract:Abstract Diabetes increases the risk of bone fracture. Organic and inorganic bone extracellular matrix components determine bone strength. Previous studies indicate that in diabetes, glycation of collagen causes abnormal arrangements of collagen molecules and fragile bones. Diabetic bone fragility is additionally attributed to reduced levels of lysyl oxidase enzyme-dependent collagen cross-links. The mechanism underlying the presence of lower enzymatic collagen cross-links in diabetic bone has not been directly investigated. Here we determine in primary osteoblast cultures the regulation of lysyl oxidase protein by type I collagen and collagen modified by carboxymethylation (CML-collagen), a form of advanced glycation endproducts. Data indicate that non-glycated collagen up-regulates lysyl oxidase levels both in primary non-differentiated and in differentiating mouse and rat osteoblast cultures, while CML-collagen fails to regulate lysyl oxidase in these cells. Collagen binding to Discoidin Domain Receptor-2 (DDR2) mediates lysyl oxidase increases, determined in DDR2 shRNA knockdown studies. DDR2 binding and activation were disrupted by collagen glycation, pointing to a mechanism for the diminished levels of lysyl oxidase and consequently low lysyl oxidase-derived cross-links in diabetic bone. Our studies indicate that collagen–integrin interactions may not play a major role in up-regulating lysyl oxidase. Furthermore, non-collagenous ligands for the receptor for advanced glycation end products (RAGE) failed to alter lysyl oxidase levels. Taken together with published studies a new understanding emerges in which diabetes- and age-dependent inhibition of normal collagen-stimulated DDR2- and integrin-signaling, and independent advanced glycation-stimulated RAGE-signaling, each contributes to different aspects of diabetic osteopenia.
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The Propeptide Domain of Lysyl Oxidase Induces Phenotypic Reversion of Ras-transformed Cells
The Journal of biological chemistry, 2004Co-Authors: Amitha H Palamakumbura, P. Sommer, S. Jeay, Y. Guo, N. Pischon, Ge Sonenshein, Philip C TrackmanAbstract:Abstract Lysyl oxidase is an extracellular enzyme critical for the normal biosynthesis of collagens and elastin. In addition, lysyl oxidase reverts ras-mediated transformation, and lysyl oxidase expression is down-regulated in human cancers. Since suramin inhibits growth factor signaling pathways and induces lysyl oxidase in ras-transformed NIH3T3 cells (RS485 cells), we sought to investigate the effects of suramin on the phenotype of transformed cells and the role of lysyl oxidase in mediating these effects. Suramin treatment resulted in a more normal phenotype as judged by growth rate, cell cycle parameters, and morphology. β-aminopropionitrile, the selective inhibitor of lysyl oxidase enzyme activity, was remarkably unable to block suramin-induced reversion. By contrast, ectopic antisense lysyl oxidase demonstrated that lysyl oxidase gene expression mediated phenotypic reversion. Since lysyl oxidase is synthesized as a 50 kDa precursor and processed to a 30 kDa active enzyme and 18 kDa propeptide, the effects of these two products on the transformed phenotype of RS485 cells were then directly assessed in the absence of suramin. Here we report, for the first time, that the lysyl oxidase propeptide, and not the lysyl oxidase enzyme, inhibits ras-dependent transformation as determined by effects on cell proliferation assays, growth in soft agar, and Akt-dependent induction of NF-κB activity. Thus, the lysyl oxidase propeptide, which is released during extracellular proteolytic processing of pro-lysyl oxidase, functions to inhibit ras-dependent cell transformation.
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Autocrine growth factor regulation of lysyl oxidase expression in transformed fibroblasts.
The Journal of biological chemistry, 2003Co-Authors: Amitha H Palamakumbura, P. Sommer, Philip C TrackmanAbstract:Lysyl oxidase catalyzes oxidative deamination of peptidyl-lysine and hydroxylysine residues in collagens and lysine residues in elastin to form peptidyl aldehydes that are required for the formation of covalent cross-links in normal extracellular matrix biosynthesis. Lysyl oxidase in addition has tumor suppressor activity, and phenotypic reversion of transformed cell lines is accompanied by increased lysyl oxidase expression. The mechanism of low expression of lysyl oxidase in tumor cells is unknown. The present study investigates the hypothesis that autocrine growth factor pathways maintain low lysyl oxidase expression levels in c-H-ras-transformed fibroblasts (RS485 cell line). Autocrine pathways were blocked with suramin, a general inhibitor of growth factor receptor binding, and resulted in more than a 10-fold increase in lysyl oxidase expression and proenzyme production. This regulation was found to be reversible and occurred at the transcriptional level determined using lysyl oxidase promoter/reporter gene assays. Function blocking anti-fibroblast growth factor-2 (FGF-2) antibody enhanced lysyl oxidase expression in the absence of suramin. Finally, the addition of FGF-2 to suramin-treated cells completely reversed suramin stimulation of lysyl oxidase mRNA levels. Data support that an FGF-2 autocrine pathway inhibits lysyl oxidase transcription in the tumorigenic-transformed RS485 cell line. This finding may be of therapeutic significance and, in addition, provides a new experimental approach to investigate the mechanism of the tumor suppressor activity of lysyl oxidase.
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Multiple Bone Morphogenetic Protein 1-related Mammalian Metalloproteinases Process Pro-lysyl Oxidase at the Correct Physiological Site and Control Lysyl Oxidase Activation in Mouse Embryo Fibroblast Cultures
Journal of Biological Chemistry, 2001Co-Authors: Mehmet Ilhan Uzel, Daniel S. Greenspan, Amitha H Palamakumbura, William N Pappano, Hermik Babakhanlou-chase, Hsiang-hsi Hong, Ian C. Scott, Philip C TrackmanAbstract:Abstract Lysyl oxidase catalyzes the final enzymatic step required for collagen and elastin cross-linking in extracellular matrix biosynthesis. Pro-lysyl oxidase is processed by procollagen C-proteinase activity, which also removes the C-propeptides of procollagens I–III. The Bmp1 gene encodes two procollagen C-proteinases: bone morphogenetic protein 1 (BMP-1) and mammalian Tolloid (mTLD). Mammalian Tolloid-like (mTLL)-1 and -2 are two genetically distinct BMP-1-related proteinases, and mTLL-1 has been shown to have procollagen C-proteinase activity. The present study is the first to directly compare pro-lysyl oxidase processing by these four related proteinases. In vitro assays with purified recombinant enzymes show that all four proteinases productively cleave pro-lysyl oxidase at the correct physiological site but that BMP-1 is 3-, 15-, and 20-fold more efficient than mTLL-1, mTLL-2, and mTLD, respectively. To more directly assess the roles of BMP-1 and mTLL-1 in lysyl oxidase activation by connective tissue cells, fibroblasts cultured from Bmp1-null,Tll1-null, and Bmp1/Tll1 double null mouse embryos, thus lacking BMP-1/mTLD, mTLL-1, or all three enzymes, respectively, were assayed for lysyl oxidase enzyme activity and for accumulation of pro-lysyl oxidase and mature ∼30-kDa lysyl oxidase. Wild type cells or cells singly null for Bmp1 orTll1 all produced both pro-lysyl oxidase and processed lysyl oxidase at similar levels, indicating apparently normal levels of processing, consistent with enzyme activity data. In contrast, double null Bmp1/Tll1 cells produced predominantly unprocessed 50-kDa pro-lysyl oxidase and had lysyl oxidase enzyme activity diminished by 70% compared with wild type, Bmp1-null, andTll1-null cells. Thus, the combination of BMP-1/mTLD and mTLL-1 is shown to be responsible for the majority of processing leading to activation of lysyl oxidase by murine embryonic fibroblasts, whereas in vitro studies identify pro-lysyl oxidase as the first known substrate for mTLL-2.
P. Sommer - One of the best experts on this subject based on the ideXlab platform.
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The Propeptide Domain of Lysyl Oxidase Induces Phenotypic Reversion of Ras-transformed Cells
The Journal of biological chemistry, 2004Co-Authors: Amitha H Palamakumbura, P. Sommer, S. Jeay, Y. Guo, N. Pischon, Ge Sonenshein, Philip C TrackmanAbstract:Abstract Lysyl oxidase is an extracellular enzyme critical for the normal biosynthesis of collagens and elastin. In addition, lysyl oxidase reverts ras-mediated transformation, and lysyl oxidase expression is down-regulated in human cancers. Since suramin inhibits growth factor signaling pathways and induces lysyl oxidase in ras-transformed NIH3T3 cells (RS485 cells), we sought to investigate the effects of suramin on the phenotype of transformed cells and the role of lysyl oxidase in mediating these effects. Suramin treatment resulted in a more normal phenotype as judged by growth rate, cell cycle parameters, and morphology. β-aminopropionitrile, the selective inhibitor of lysyl oxidase enzyme activity, was remarkably unable to block suramin-induced reversion. By contrast, ectopic antisense lysyl oxidase demonstrated that lysyl oxidase gene expression mediated phenotypic reversion. Since lysyl oxidase is synthesized as a 50 kDa precursor and processed to a 30 kDa active enzyme and 18 kDa propeptide, the effects of these two products on the transformed phenotype of RS485 cells were then directly assessed in the absence of suramin. Here we report, for the first time, that the lysyl oxidase propeptide, and not the lysyl oxidase enzyme, inhibits ras-dependent transformation as determined by effects on cell proliferation assays, growth in soft agar, and Akt-dependent induction of NF-κB activity. Thus, the lysyl oxidase propeptide, which is released during extracellular proteolytic processing of pro-lysyl oxidase, functions to inhibit ras-dependent cell transformation.
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The propeptide domain of lysyl oxidase induces phenotypic reversion of ras-transformed cells.
Journal of Biological Chemistry, 2004Co-Authors: Ah Palamakumbura, P. Sommer, S. Jeay, Y. Guo, N. Pischon, Ge Sonenshein, Pc TrackmanAbstract:Lysyl oxidase is an extracellular enzyme critical for the normal biosynthesis of collagens and elastin. In addition, lysyl oxidase reverts ras-mediated transformation, and lysyl oxidase expression is down-regulated in human cancers. Since suramin inhibits growth factor signaling pathways and induces lysyl oxidase in ras-transformed NIH3T3 cells (RS485 cells), we sought to investigate the effects of suramin on the phenotype of transformed cells and the role of lysyl oxidase in mediating these effects. Suramin treatment resulted in a more normal phenotype as judged by growth rate, cell cycle parameters, and morphology. beta-aminopropionitrile, the selective inhibitor of lysyl oxidase enzyme activity, was remarkably unable to block suramin-induced reversion. By contrast, ectopic antisense lysyl oxidase demonstrated that lysyl oxidase gene expression mediated phenotypic reversion. Since lysyl oxidase is synthesized as a 50 kDa precursor and processed to a 30 kDa active enzyme and 18 kDa propeptide, the effects of these two products on the transformed phenotype of RS485 cells were then directly assessed in the absence of suramin. Here we report, for the first time, that the lysyl oxidase propeptide, and not the lysyl oxidase enzyme, inhibits ras-dependent transformation as determined by effects on cell proliferation assays, growth in soft agar, and Akt-dependent induction of NF-kappaB activity. Thus, the lysyl oxidase propeptide, which is released during extracellular proteolytic processing of pro-lysyl oxidase, functions to inhibit ras-dependent cell transformation.Lysyl oxidase is an extracellular enzyme critical for the normal biosynthesis of collagens and elastin. In addition, lysyl oxidase reverts ras-mediated transformation, and lysyl oxidase expression is down-regulated in human cancers. Since suramin inhibits growth factor signaling pathways and induces lysyl oxidase in ras-transformed NIH3T3 cells (RS485 cells), we sought to investigate the effects of suramin on the phenotype of transformed cells and the role of lysyl oxidase in mediating these effects. Suramin treatment resulted in a more normal phenotype as judged by growth rate, cell cycle parameters, and morphology. beta-aminopropionitrile, the selective inhibitor of lysyl oxidase enzyme activity, was remarkably unable to block suramin-induced reversion. By contrast, ectopic antisense lysyl oxidase demonstrated that lysyl oxidase gene expression mediated phenotypic reversion. Since lysyl oxidase is synthesized as a 50 kDa precursor and processed to a 30 kDa active enzyme and 18 kDa propeptide, the effects of these two products on the transformed phenotype of RS485 cells were then directly assessed in the absence of suramin. Here we report, for the first time, that the lysyl oxidase propeptide, and not the lysyl oxidase enzyme, inhibits ras-dependent transformation as determined by effects on cell proliferation assays, growth in soft agar, and Akt-dependent induction of NF-kappaB activity. Thus, the lysyl oxidase propeptide, which is released during extracellular proteolytic processing of pro-lysyl oxidase, functions to inhibit ras-dependent cell transformation.
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Autocrine growth factor regulation of lysyl oxidase expression in transformed fibroblasts.
The Journal of biological chemistry, 2003Co-Authors: Amitha H Palamakumbura, P. Sommer, Philip C TrackmanAbstract:Lysyl oxidase catalyzes oxidative deamination of peptidyl-lysine and hydroxylysine residues in collagens and lysine residues in elastin to form peptidyl aldehydes that are required for the formation of covalent cross-links in normal extracellular matrix biosynthesis. Lysyl oxidase in addition has tumor suppressor activity, and phenotypic reversion of transformed cell lines is accompanied by increased lysyl oxidase expression. The mechanism of low expression of lysyl oxidase in tumor cells is unknown. The present study investigates the hypothesis that autocrine growth factor pathways maintain low lysyl oxidase expression levels in c-H-ras-transformed fibroblasts (RS485 cell line). Autocrine pathways were blocked with suramin, a general inhibitor of growth factor receptor binding, and resulted in more than a 10-fold increase in lysyl oxidase expression and proenzyme production. This regulation was found to be reversible and occurred at the transcriptional level determined using lysyl oxidase promoter/reporter gene assays. Function blocking anti-fibroblast growth factor-2 (FGF-2) antibody enhanced lysyl oxidase expression in the absence of suramin. Finally, the addition of FGF-2 to suramin-treated cells completely reversed suramin stimulation of lysyl oxidase mRNA levels. Data support that an FGF-2 autocrine pathway inhibits lysyl oxidase transcription in the tumorigenic-transformed RS485 cell line. This finding may be of therapeutic significance and, in addition, provides a new experimental approach to investigate the mechanism of the tumor suppressor activity of lysyl oxidase.
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Autocrine growth factor regulation of lysyl oxidase expression in transformed fibroblasts.
Journal of Biological Chemistry, 2003Co-Authors: Ah Palamakumbura, P. Sommer, Pc TrackmanAbstract:Lysyl oxidase catalyzes oxidative deamination of peptidyl-lysine and hydroxylysine residues in collagens and lysine residues in elastin to form peptidyl aldehydes that are required for the formation of covalent cross-links in normal extracellular matrix biosynthesis. Lysyl oxidase in addition has tumor suppressor activity, and phenotypic reversion of transformed cell lines is accompanied by increased lysyl oxidase expression. The mechanism of low expression of lysyl oxidase in tumor cells is unknown. The present study investigates the hypothesis that autocrine growth factor pathways maintain low lysyl oxidase expression levels in c-H-ras-transformed fibroblasts (RS485 cell line). Autocrine pathways were blocked with suramin, a general inhibitor of growth factor receptor binding, and resulted in more than a 10-fold increase in lysyl oxidase expression and proenzyme production. This regulation was found to be reversible and occurred at the transcriptional level determined using lysyl oxidase promoter/reporter gene assays. Function blocking anti-fibroblast growth factor-2 (FGF-2) antibody enhanced lysyl oxidase expression in the absence of suramin. Finally, the addition of FGF-2 to suramin-treated cells completely reversed suramin stimulation of lysyl oxidase mRNA levels. Data support that an FGF-2 autocrine pathway inhibits lysyl oxidase transcription in the tumorigenic-transformed RS485 cell line. This finding may be of therapeutic significance and, in addition, provides a new experimental approach to investigate the mechanism of the tumor suppressor activity of lysyl oxidase.Lysyl oxidase catalyzes oxidative deamination of peptidyl-lysine and hydroxylysine residues in collagens and lysine residues in elastin to form peptidyl aldehydes that are required for the formation of covalent cross-links in normal extracellular matrix biosynthesis. Lysyl oxidase in addition has tumor suppressor activity, and phenotypic reversion of transformed cell lines is accompanied by increased lysyl oxidase expression. The mechanism of low expression of lysyl oxidase in tumor cells is unknown. The present study investigates the hypothesis that autocrine growth factor pathways maintain low lysyl oxidase expression levels in c-H-ras-transformed fibroblasts (RS485 cell line). Autocrine pathways were blocked with suramin, a general inhibitor of growth factor receptor binding, and resulted in more than a 10-fold increase in lysyl oxidase expression and proenzyme production. This regulation was found to be reversible and occurred at the transcriptional level determined using lysyl oxidase promoter/reporter gene assays. Function blocking anti-fibroblast growth factor-2 (FGF-2) antibody enhanced lysyl oxidase expression in the absence of suramin. Finally, the addition of FGF-2 to suramin-treated cells completely reversed suramin stimulation of lysyl oxidase mRNA levels. Data support that an FGF-2 autocrine pathway inhibits lysyl oxidase transcription in the tumorigenic-transformed RS485 cell line. This finding may be of therapeutic significance and, in addition, provides a new experimental approach to investigate the mechanism of the tumor suppressor activity of lysyl oxidase.
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Lysyl oxidase-like protein from bovine aorta. Isolation and maturation to an active form by bone morphogenetic protein-1.
Journal of Biological Chemistry, 2001Co-Authors: A. Borel, P. Sommer, C. Gleyzal, Dj Hulmes, D. Eichenberger, J. Farjanel, E. Kessler, B. FontAbstract:Recently several cDNAs have been described encoding lysyl oxidase-like proteins. Their deduced amino acid sequences are characterized by a strong similarity in the C-terminal region, corresponding to the lysyl oxidase family catalytic domain, and by marked differences in the N-terminal regions. Different biological functions have been described for lysyl oxidases in addition to their traditionally assumed cross-linking role. To answer the question of whether these different functions are carried out by different lysyl oxidases, purified and active forms of these enzymes are required. At present only the classical form of lysyl oxidase has been purified and characterized. The purpose of this study was to isolate and characterize the lysyl oxidase-like protein. In view of the strong sequence homology with the C-terminal domain of other lysyl oxidases, we chose to purify the protein from bovine aorta using antibodies specific to the N-terminal domain of the proenzyme. We have isolated a 56-kDa protein identified by amino acid sequencing as the bovine lysyl oxidase-like precursor, which is cleaved at the Arg-Arg-Arg sequence at positions 89-91 by a furin-like activity, as revealed after deblocking of the N-terminal residue. The immunopurified protein was largely inactive, but further processing in vitro by bone morphogenetic protein-1 led to an enzyme that was active on elastin and collagen substrates.Recently several cDNAs have been described encoding lysyl oxidase-like proteins. Their deduced amino acid sequences are characterized by a strong similarity in the C-terminal region, corresponding to the lysyl oxidase family catalytic domain, and by marked differences in the N-terminal regions. Different biological functions have been described for lysyl oxidases in addition to their traditionally assumed cross-linking role. To answer the question of whether these different functions are carried out by different lysyl oxidases, purified and active forms of these enzymes are required. At present only the classical form of lysyl oxidase has been purified and characterized. The purpose of this study was to isolate and characterize the lysyl oxidase-like protein. In view of the strong sequence homology with the C-terminal domain of other lysyl oxidases, we chose to purify the protein from bovine aorta using antibodies specific to the N-terminal domain of the proenzyme. We have isolated a 56-kDa protein identified by amino acid sequencing as the bovine lysyl oxidase-like precursor, which is cleaved at the Arg-Arg-Arg sequence at positions 89-91 by a furin-like activity, as revealed after deblocking of the N-terminal residue. The immunopurified protein was largely inactive, but further processing in vitro by bone morphogenetic protein-1 led to an enzyme that was active on elastin and collagen substrates.
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Efficacy of various disinfectants in killing a resistant strain of Pseudomonas aeruginosa by comparing zones of inhibition: implications for endoscopic equipment reprocessing.
The American journal of gastroenterology, 1998Co-Authors: Brent J Kovacs, Raydolfo M. Aprecio, James D. Kettering, Yang K. ChenAbstract:Previous studies have shown that high-level disinfection of GI endoscopes may not be reliably achieved using glutaraldehyde at room temperature. In our laboratory, we have isolated a strain of Pseudomonas aeruginosa that is resistant to disinfection with glutaraldehyde. We compared the bactericidal activity of various disinfectants against this organism. One hundred microliters of an overnight culture of this organism was spread onto blood agar plates. Twenty microliters of a disinfectant was placed on a sterile 7-mm filter paper, placed on the blood agar plate, and incubated overnight at 37 degrees C to determine the zone of inhibition for each disinfectant tested. Disinfectants included Cidex, Dispatch, Virahol, OMNI II, Lysol, IodoFive, Lysol I.C. Spray, and Chlorox. The zone of inhibition (i.e., clearing) roughly correlates with the bactericidal strength of the disinfectant. Compared with the glutaraldehyde-containing solution Cidex, the alcohol-containing disinfectants Lysol I.C. Spray and Virahol had the largest mean zones of inhibition (11.33 vs 20.60 and 20.55 mm; p = 0.0001). The hypochlorite compounds Chlorox (1:10 dilution) and Dispatch had mean zones of inhibition similar to that of Cidex (11.08 and 11.25 mm vs 11.33 mm; p = not significant). The phenolic compounds OMNI II and Lysol had mean zones of inhibition smaller than that of Cidex (10.50 and 10.35 mm vs 11.33 mm; p < 0.006), and the phosphoric acid and iodine-containing IodoFive had the smallest mean zone of inhibition (9.70 vs 11.33 mm; p = 0.0001). The alcohol-containing disinfectants had the largest zones of inhibition against resistant P. aeruginosa. These compounds may be more effective than glutaraldehyde for endoscopic equipment reprocessing.
