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1.
Life Sci Space Res (Amst) ; 18: 1-11, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30100142

RESUMO

As manned spaceflights beyond low Earth orbit are in the agenda of Space Agencies, the concerns related to space radiation exposure of the crew are still without conclusive solutions. The risk of long-term detrimental health effects needs to be kept below acceptable limits, and emergency countermeasures must be planned to avoid the short-term consequences of exposure to high particle fluxes during hardly predictable solar events. Space habitat shielding cannot be the ultimate solution: the increasing complexity of future missions will require astronauts to protect themselves in low-shielded areas, e.g. during emergency operations. Personal radiation shielding is promising, particularly if using available resources for multi-functional shielding devices. In this work we report on all steps from the conception, design, manufacturing, to the final test on board the International Space Station (ISS) of the first prototype of a water-filled garment for emergency radiation shielding against solar particle events. The garment has a good shielding potential and comfort level. On-board water is used for filling and then recycled without waste. The successful outcome of this experiment represents an important breakthrough in space radiation shielding, opening to the development of similarly conceived devices and their use in interplanetary missions as the one to Mars.


Assuntos
Astronautas , Radiação Cósmica/efeitos adversos , Proteção Radiológica/instrumentação , Trajes Espaciais/normas , Vestuário , Humanos , Modelos Teóricos , Imagens de Fantasmas , Doses de Radiação , Lesões por Radiação/etiologia , Lesões por Radiação/prevenção & controle , Voo Espacial
3.
Neuromuscul Disord ; 24(11): 990-2, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25088310

RESUMO

We report two siblings of Croatian consanguineous healthy parents with a novel homozygous missense mutation in the POMT1 gene, presenting with intellectual disability and psychotic, in particular hallucinatory symptoms and abnormal brain MRIs, preceding classical symptoms of limb-girdle muscular dystrophy by several years. Weakness became apparent in early adulthood and both siblings remained ambulant into the 3rd and 4th decade of life. The muscle biopsy showed reduced α-dystroglycan compatible with the POMT1 defect. This case report extends the phenotypic spectrum of POMT1 associated muscular dystrophies to the adult onset limb girdle muscular dystrophies with psycho-organic deficits.


Assuntos
Transtornos Cognitivos/etiologia , Manosiltransferases/genética , Transtornos Mentais/etiologia , Distrofia Muscular do Cíngulo dos Membros/complicações , Distrofia Muscular do Cíngulo dos Membros/genética , Mutação/genética , Adulto , Encéfalo/patologia , Transtornos Cognitivos/genética , Consanguinidade , Análise Mutacional de DNA , Feminino , Humanos , Imageamento por Ressonância Magnética , Transtornos Mentais/genética , Irmãos
5.
Neurology ; 70(14): 1192-9, 2008 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-18378883

RESUMO

OBJECTIVE: Mutations in COL6A1, COL6A2, and COL6A3, the genes that encode the extracellular matrix component collagen VI, lead to Bethlem myopathy (BM) and Ullrich congenital muscular dystrophy (UCMD). Unlike UCMD, BM is difficult to diagnose because of its clinical overlap with other contractural phenotypes and the lack of sensitivity of standard muscle biopsy immunohistochemical diagnostic techniques. METHODS: We appraised two potential techniques for the diagnosis of BM: dual immunofluorescence (IF) for collagen VI and basal lamina-located perlecan in muscle, and immunofluorescent labeling of collagen VI in skin biopsy-derived fibroblast cultures, which was conducted in 40 patients by blinded investigators and correlated with genetic findings. RESULTS: Dual IF was indistinguishable from normal controls in most BM patients. However, abnormalities in the IF labeling pattern of collagen VI were detected in more than 78% of genetically confirmed BM patient fibroblast cell lines. In addition, in a group of patients with unknown diagnosis studied prospectively, the fibroblast IF technique was highly predictive of the presence of a COL6A mutation, providing a positive predictive value of 75%, a sensitivity and negative predictive value of 100%, and a specificity of 63%. CONCLUSIONS: Immunofluorescent labeling of collagen VI in fibroblast cultures is a useful addition to current diagnostic services for Bethlem myopathy (BM). It can be used to guide molecular genetic testing, the gold standard diagnostic technique for BM, in a cost-effective and time-saving manner.


Assuntos
Algoritmos , Colágeno Tipo VI/metabolismo , Fibroblastos/metabolismo , Músculo Esquelético/metabolismo , Doenças Musculares/diagnóstico , Doenças Musculares/metabolismo , Células Cultivadas , Colágeno Tipo VI/análise , Colágeno Tipo VI/genética , Análise Mutacional de DNA , Fibroblastos/imunologia , Imunofluorescência/métodos , Imunofluorescência/normas , Proteoglicanas de Heparan Sulfato/análise , Proteoglicanas de Heparan Sulfato/imunologia , Proteoglicanas de Heparan Sulfato/metabolismo , Humanos , Biologia Molecular/métodos , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Diagnóstico Molecular/normas , Músculo Esquelético/imunologia , Músculo Esquelético/fisiopatologia , Doenças Musculares/genética , Mutação/genética , Valor Preditivo dos Testes , Estudos Prospectivos , Estudos Retrospectivos , Método Simples-Cego , Pele/citologia , Pele/imunologia , Pele/metabolismo
6.
Neuromuscul Disord ; 18(4): 288-90, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18396043

RESUMO

LGMD2B, Miyoshi Myopathy and Distal Anterior Compartment Myopathy are caused by mutations in the dysferlin gene (DYSF) leading to progressive muscular weakness and wasting with onset usually within the second or third decade of life. We here present a patient with disease onset at 73 years. The presenting symptom was exercise-induced stiffness of the trunk and proximal leg muscles without major progression over a period of 12 years. Gastrocnemius muscle biopsy revealed dystrophic morphology and biochemical depletion of dysferlin, while sequence analysis revealed compound heterozygous splicing mutations of the dysferlin gene. This case represents the eldest age of onset of dysferlinopathy reported so far and widens the clinical spectrum of this disease.


Assuntos
Proteínas de Membrana/genética , Proteínas Musculares/genética , Distrofia Muscular do Cíngulo dos Membros/genética , Mutação , Idoso , Análise Mutacional de DNA , Disferlina , Feminino , Humanos , Músculo Esquelético/patologia , Distrofia Muscular do Cíngulo dos Membros/patologia , Distrofia Muscular do Cíngulo dos Membros/fisiopatologia
7.
J Biol Chem ; 275(49): 38554-60, 2000 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-10993904

RESUMO

The sarcoglycan complex in striated muscle is a heterotetrameric unit integrally associated with sarcospan in the dystrophin-glycoprotein complex. The sarcoglycans, alpha, beta, gamma, and delta, are mutually dependent with regard to their localization at the sarcolemma, and mutations in any of the sarcoglycan genes lead to limb-girdle muscular dystrophies type 2C-2F. In smooth muscle beta- and delta-sarcoglycans are associated with epsilon-sarcoglycan, a glycoprotein homologous to alpha-sarcoglycan. Here, we demonstrate that gamma-sarcoglycan is also a component of the sarcoglycan complex in the smooth muscle. First, we show the presence of gamma-sarcoglycan in a number of smooth muscle-containing organs, and we verify the existence of identical transcripts in skeletal and smooth muscle. The specificity of the expression of gamma-sarcoglycan in smooth muscle was confirmed by analysis of smooth muscle cells in culture. Next, we provide evidence for the association of gamma-sarcoglycan with the sarcoglycan-sarcospan complex by biochemical analysis and comparison among animal models for muscular dystrophy. Moreover, we find disruption of the sarcoglycan complex in the vascular smooth muscle of a patient with gamma-sarcoglycanopathy. Taken together, our results prove that the sarcoglycan complex in vascular and visceral smooth muscle consists of epsilon-, beta-, gamma-, and delta-sarcoglycans and is associated with sarcospan.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas do Citoesqueleto/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana/metabolismo , Músculo Liso/metabolismo , Proteínas de Neoplasias , Transcrição Gênica , Sequência de Aminoácidos , Animais , Proteínas do Citoesqueleto/deficiência , Proteínas do Citoesqueleto/genética , Distroglicanas , Humanos , Glicoproteínas de Membrana/deficiência , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos mdx , Camundongos Knockout , Dados de Sequência Molecular , Músculo Esquelético/metabolismo , Distrofias Musculares/genética , Distrofias Musculares/metabolismo , Distrofias Musculares/patologia , Sarcoglicanas
8.
Transfus Sci ; 22(3): 161-4, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10831918

RESUMO

UNLABELLED: Although it is infrequent, post-transfusion HCV infection may occur if the donors blood is collected in the window period between exposure and anti-HCV detectability by ELISA testing. STUDY DESIGN: In these last years, despite of routine application of anti-HCV testing, our blood transfusion center has been involved in 53 cases of alleged post-transfusion HCV hepatitis and look-back programs were set up with the goal of finding out the donors possibly involved in viral transmission. Most of these patients were hematological cases with multiple transfusions given because of aplastic anemia (3 cases), leukemia with or without bone marrow transplantation (5/4 cases) but necessitating long-term platelet support, leukemia and solid cancer patients undergoing autologous PBSC transplantation (3/4 cases) and TTP (2 cases). Only 32 patients were of the simple medical or surgical type, 9 transfused because of cardiac or vascular surgery, 8 because of spine surgery, 5 for different diseases and 5 for different types of cancer surgery. Donor's infectivity was determined by ELISA anti-HCV testing, by recombinant immunoblotting assay, and by nucleic acid testing. RESULTS AND CONCLUSION: No donors out of 267 traced of a total of 359 involved was found with anti-HCV seroconversion, or positive on PCR testing. This suggests that the responsibility for HCV transmission can only hypothetically be related to blood or blood components and that other transmission routes should be found out.


Assuntos
Transfusão de Sangue/normas , Hepacivirus , Anticorpos Anti-Hepatite C/sangue , Hepatite C/transmissão , Doadores de Sangue/legislação & jurisprudência , Transfusão de Sangue/legislação & jurisprudência , Transmissão de Doença Infecciosa/economia , Transmissão de Doença Infecciosa/legislação & jurisprudência , Hepacivirus/genética , Hepatite C/sangue , Hepatite C/epidemiologia , Humanos , Itália , Reação em Cadeia da Polimerase , Vigilância da População , RNA Viral/sangue , Estudos Soroepidemiológicos , Reação Transfusional
9.
Cell ; 98(4): 465-74, 1999 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-10481911

RESUMO

To investigate mechanisms in the pathogenesis of cardiomyopathy associated with mutations of the dystrophin-glycoprotein complex, we analyzed genetically engineered mice deficient for either alpha-sarcoglycan (Sgca) or delta-sarcoglycan (Sgcd). We found that only Sgcd null mice developed cardiomyopathy with focal areas of necrosis as the histological hallmark in cardiac and skeletal muscle. Absence of the sarcoglycan-sarcospan (SG-SSPN) complex in skeletal and cardiac membranes was observed in both animal models. Loss of vascular smooth muscle SG-SSPN complex was only detected in Sgcd null mice and associated with irregularities of the coronary vasculature. Administration of a vascular smooth muscle relaxant prevented onset of myocardial necrosis. Our data indicate that disruption of the SG-SSPN complex in vascular smooth muscle perturbs vascular function, which initiates cardiomyopathy and exacerbates muscular dystrophy.


Assuntos
Cardiomiopatia Dilatada/genética , Proteínas de Transporte/fisiologia , Proteínas do Citoesqueleto/fisiologia , Glicoproteínas de Membrana/fisiologia , Proteínas de Membrana/fisiologia , Músculo Liso Vascular/metabolismo , Distrofia Muscular Animal/genética , Proteínas de Neoplasias , Animais , Cardiomiopatia Dilatada/metabolismo , Cardiomiopatia Dilatada/patologia , Vasos Coronários/patologia , Proteínas do Citoesqueleto/deficiência , Proteínas do Citoesqueleto/genética , Substâncias Macromoleculares , Glicoproteínas de Membrana/deficiência , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Knockout , Músculo Liso Vascular/patologia , Distrofia Muscular Animal/metabolismo , Distrofia Muscular Animal/patologia , Miocárdio/patologia , Necrose , Condicionamento Físico Animal/efeitos adversos , Sarcoglicanas
10.
Arch Surg ; 134(2): 212-7, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10025466

RESUMO

Advances in minimally invasive surgery have made it possible to remove solid organs such as the adrenal gland laparoscopically. Several studies have shown that when applied to appropriate operative candidates, laparoscopic adrenalectomy is a safe alternative to conventional open surgery with real advantages in terms of decreasing postoperative pain and length of hospital stay and allowing earlier return to normal activity. The indications for laparoscopic adrenalectomy are essentially the same as those described for open adrenalectomy. We do not recommend laparoscopic adrenalectomy for known primary or metastatic malignant tumors of the adrenal glands, because of the risk of tumor implantation that might compromise the patient's chance for cure, nor do we recommend it for lesions larger than 6 to 8 cm where the chance of malignancy is high. The preoperative preparation, laparoscopic instruments, operative techniques, and potential complications and their treatments are described in this review. Laparoscopic adrenalectomy is becoming the preferred method of surgically treating many adrenal problems. Although conventional surgical approaches will undoubtedly be required to treat certain adrenal lesions, surgeons with an interest in treating patients with adrenal disorders must become proficient in the technique of laparoscopic adrenalectomy. This will allow them to select the most appropriate operative approach for their patients' individual problems.


Assuntos
Adrenalectomia/métodos , Laparoscopia/métodos , Humanos
11.
Ann Neurol ; 42(2): 249-53, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9266737

RESUMO

We have raised an anti-emerin polyclonal antibody against a fusion protein encompassing most of the hydrophilic portion of emerin. Using this antibody, we have analyzed emerin expression in Emery-Dreifuss muscular dystrophy (EDMD) patients and controls, by immunocytochemistry, in skeletal muscle and skin, and by immunoblot, in peripheral blood mononuclear cells and lymphoblasts. Emerin was localized on the surfaces of nuclei in control skeletal muscle and skin but was absent or reduced in patient skeletal muscle, was absent from the skin of patients, and was expressed only in a few nuclei in a patient's mother. Immunoblot of peripheral blood cells from EDMD patients showed absence of the emerin band, altered-size emerin, or a protein of normal molecular mass but slightly reduced quantity. The diagnosis of X-linked EDMD is normally confirmed by genetic analysis of the STA gene coding for emerin. We propose immunocytochemical evaluation of emerin expression in skin biopsies as a sensitive and more convenient tool for diagnosing X-linked EDMD and, in particular, for distinguishing it from the autosomal dominant form. This technique may be applied to suspected EDMD patients, especially sporadic cases or those with incomplete clinical phenotype, and also suspected carriers. Immunoblot of peripheral blood cells is also useful, but it may not unequivocally identify carriers and some patients.


Assuntos
Leucócitos Mononucleares/metabolismo , Linfócitos/metabolismo , Proteínas de Membrana/análise , Distrofias Musculares/diagnóstico , Distrofias Musculares/genética , Pele/patologia , Timopoietinas/análise , Cromossomo X , Adolescente , Adulto , Biomarcadores , Biópsia , Pré-Escolar , Feminino , Humanos , Imuno-Histoquímica , Laminas , Leucócitos Mononucleares/patologia , Linfócitos/patologia , Masculino , Proteínas de Membrana/biossíntese , Músculo Esquelético/metabolismo , Distrofias Musculares/sangue , Distrofias Musculares/patologia , Distrofia Muscular de Emery-Dreifuss , Proteínas Nucleares/análise , Valores de Referência , Pele/citologia , Pele/metabolismo , Timopoietinas/biossíntese
12.
J Neuroimmunol ; 68(1-2): 53-60, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8784260

RESUMO

Major histocompatibility complex (MHC) class II molecules are expressed on myoblasts after interferon-gamma (IFN-gamma) treatment, suggesting a muscle cell involvement in antigen presentation in inflammatory myopathies. However, they were not observed on normal or pathological myofibers. This discrepancy might be related to different responsiveness of developmentally differentiated muscle cells to IFN-gamma. Myoblasts expressed class II transcripts and proteins after IFN-gamma, while myotubes and innervated contracting muscle cells did not show staining for class II molecules. At all cell stages no loss of IFN-gamma receptor was detected indicating that myofiber maturation blocks their capacity to express MHC class II molecules. This suggests that completely differentiated myofibers cannot participate in class II restricted immunological reactions.


Assuntos
Doenças Autoimunes/imunologia , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/imunologia , Músculo Esquelético/imunologia , Doenças Musculares/imunologia , Actinas/genética , Antígenos CD/genética , Antígenos de Diferenciação de Linfócitos B/genética , Sequência de Bases , Diferenciação Celular/imunologia , Fusão Celular/imunologia , Células Cultivadas/química , Células Cultivadas/efeitos dos fármacos , Células Cultivadas/imunologia , Expressão Gênica/imunologia , Humanos , Interferon gama/farmacologia , Dados de Sequência Molecular , Fibras Musculares Esqueléticas/citologia , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/imunologia , Músculo Esquelético/química , Músculo Esquelético/citologia , Miosinas/genética , RNA Mensageiro/imunologia , Receptores de Interferon/genética , Transcrição Gênica/imunologia
13.
Brain Res Dev Brain Res ; 91(1): 70-82, 1996 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-8821479

RESUMO

Dystrophin, utrophin and the dystrophin-associated glycoproteins, beta-dystroglycan and adhalin, were analyzed, together with the membrane cytoskeletal proteins beta-spectrin, vinculin and talin, and adult and fetal myosin heavy chains, in 25 normal human fetuses from 8 to 24 weeks of gestation. Dystrophin was present in heart and skeletal muscle from 8 weeks although in the latter was mainly in the cytoplasm at this stage. Utrophin expression increased until around gestational weeks 19/21, but by 24 weeks immunostaining and immunoblot band intensities had reduced. Beta-dystroglycan was scarce in skeletal muscle at 8 weeks, increased with maturation and was more abundant in heart of the same age. Adhalin appeared later than beta-dystroglycan on skeletal muscle fiber surfaces, positivity became more intense as the fibers matured. In heart adhalin was detectable only in groups of cells at 12-16 weeks. From 8 weeks all fetal myotubes expressed beta-spectrin on their surfaces, while vinculin and talin positivity was mainly at the periphery of the fascicles, increasing with age. Adult slow myosin was seen in most myotubes at 10 weeks. Secondary myotubes then formed which increasingly expressed adult fast myosin, while still retaining fetal myosin. By 24 weeks most fibers expressing adult slow myosin had lost fetal myosin and were more mature in the expression of most membrane proteins. Muscle membrane organization during human fetal development is a complex process and takes place earlier in heart than skeletal muscle.


Assuntos
Proteínas do Citoesqueleto/biossíntese , Distrofina/biossíntese , Glicoproteínas/biossíntese , Coração/crescimento & desenvolvimento , Proteínas de Membrana , Desenvolvimento Muscular , Músculo Esquelético/crescimento & desenvolvimento , Músculo Esquelético/metabolismo , Miocárdio/metabolismo , Western Blotting , Proteínas do Citoesqueleto/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Membranas/metabolismo , Miosinas/metabolismo , Gravidez , Utrofina
14.
J Clin Invest ; 96(2): 1137-44, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7635950

RESUMO

Duchenne muscular dystrophy is a fatal disorder characterized by progressive muscular weakness, wasting, and severe muscle contractures in later disease stages. Muscle biopsy reveals conspicuous myofiber degeneration and fibrosis substituting muscle tissue. We quantitatively determined mRNA of the potent fibrogenic cytokine transforming growth factor-beta 1 by quantitative PCR in 15 Duchenne muscular dystrophy, 13 Becker muscular dystrophy, 11 spinal muscular atrophy patients, and 16 controls. Higher transforming growth factor-beta 1 expression was greater in Duchenne muscular dystrophy patients than controls (P = 0.012) and Becker patients (P = 0.03). Fibrosis was significantly more prominent in Duchenne muscular dystrophy than Becker muscular dystrophy, spinal muscular atrophy, and controls. The proportion of connective tissue in muscle biopsies increased progressively with age in Duchenne muscular dystrophy patients, while transforming growth factor-beta 1 levels peaked at 2 and 6 yr of age. Transforming growth factor-beta 1 protein was also detected by immunocytochemistry and immunoblotting. Our findings suggest that transforming growth factor-beta 1 stimulates fibrosis in Duchenne muscular dystrophy. Expression of transforming growth factor-beta 1 in the early stages of Duchenne muscular dystrophy may be critical in initiating muscle fibrosis and antifibrosis treatment could slow progression of the disease, increasing the utility of gene therapy.


Assuntos
Citocinas/fisiologia , Músculos/metabolismo , Distrofias Musculares/metabolismo , Atrofias Musculares Espinais da Infância/metabolismo , Fator de Crescimento Transformador beta/biossíntese , Fatores Etários , Sequência de Bases , Criança , Pré-Escolar , Tecido Conjuntivo/patologia , Fibrose , Expressão Gênica , Humanos , Dados de Sequência Molecular , Músculos/patologia , Distrofias Musculares/classificação , Distrofias Musculares/patologia , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , Atrofias Musculares Espinais da Infância/patologia , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/fisiologia
15.
Arch Biochem Biophys ; 267(1): 245-51, 1988 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-3196028

RESUMO

K 562 cell acetylcholinesterase (AChE), identifiable by active site labeling with radioactive diisopropylfluorophosphate (DFP), showed a Mr around 55,000 in both a crude lysate and a purified sample. The K 562 AChE was reactive with one polyclonal and two monoclonal antibodies produced against human erythrocyte AChE. Subcellular localization, investigated by assay on cell fractions, showed that AChE is membrane bound and that it is located on the cell surface as well as on microsomal and Golgi membranes. Biosynthesis of new enzyme molecules, after inactivation of the constitutive AChE with the irreversible inhibitor DFP, allowed us to follow the kinetics of reappearance in the intracellular compartment and at the cell surface (4 and 8 h, respectively).


Assuntos
Acetilcolinesterase/biossíntese , Leucemia Experimental/enzimologia , Marcadores de Afinidade , Sítios de Ligação , Membrana Celular/enzimologia , Cinética , Espectrometria de Fluorescência , Frações Subcelulares/enzimologia , Células Tumorais Cultivadas
16.
Cell Differ ; 22(2): 155-8, 1988 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3342452

RESUMO

Morphological and functional differentiation of hemopoietic cells is accompanied by the expression of lineage-specific protein markers. NADPH-oxidoreductive enzymatic activities in HL 60 and K 562 leukemic cell lines, compared with granulocytes and erythrocytes, show a NADPH-oxidizing and a NADPH-diaphorase activity. The oxidizing activity, absent in erythrocytes, has the same electrophoretic migration in HL 60 cells and granulocytes while it is different in K 562 cells. The diaphorase, absent in HL 60 cells and granulocytes, has the same migration in erythrocytes and K 562 cells, although with a slightly different quantitative expression. K 562 cells induced to differentiation with arabinofuranosylcytosine show the appearance of a band of NADPH-oxidizing activity of granulocytic type, together with the major band found in these cells.


Assuntos
NADH NADPH Oxirredutases/metabolismo , Células Tumorais Cultivadas/enzimologia , Diferenciação Celular/efeitos dos fármacos , Eletroforese em Gel de Poliacrilamida/métodos , Eritrócitos/enzimologia , Granulócitos/citologia , Granulócitos/enzimologia , Humanos , Técnicas In Vitro , Leucemia Experimental/enzimologia
17.
Cancer Res ; 45(3): 1296-9, 1985 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3155991

RESUMO

Phosphoglucomutase 1, an enzyme mapping on the short arms of chromosome 1, is constantly missing in the leukemic cell line K-562 in spite of the presence of three No. 1 chromosomes. In the present work, a subclone of the cell line, K-562 (S)P, is described, where the enzyme can be demonstrated, thus excluding a small deletion as the cause for the lack of expression of phosphoglucomutase 1. The relationship between the presence of the enzyme and the karyotype changes in this subclone is analyzed. Addition of several inducers to the standard K-562 line failed to elicit expression of the enzyme.


Assuntos
Leucemia/enzimologia , Fosfoglucomutase/análise , Linhagem Celular , Aberrações Cromossômicas , Humanos , Leucemia/genética , Fosfoglucomutase/genética
18.
Cancer Res ; 44(9): 3749-51, 1984 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6589044

RESUMO

Acetylcholinesterase, an erythroid marker constitutively expressed in K-562 cells, can be further induced by sodium butyrate. The highest level of acetylcholinesterase induction is reached in approximately equal to 3 days, in parallel with increased hemoglobin expression. Acetylcholinesterase induction is reversible, and repeated addition of butyrate is necessary to maintain a high level of the enzyme. Actinomycin D inhibits the induction.


Assuntos
Acetilcolinesterase/biossíntese , Butiratos/farmacologia , Leucemia Mieloide Aguda/enzimologia , Ácido Butírico , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Cicloeximida/farmacologia , Dactinomicina/farmacologia , Indução Enzimática , Humanos , Cinética , Leucemia Mieloide Aguda/fisiopatologia
19.
Cancer Res ; 43(11): 5560-3, 1983 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6577951

RESUMO

Differentiation-dependent expression of enzyme loci was evaluated in two human leukemic cell lines, the pluripotent leukemia cell line K-562 and the promyelocytic-like cell line HL-60. Acetylcholinesterase, a marker of erythroid differentiation, was present in K-562 cells and absent in HL-60 cells. This difference between the two lines was apparently unrelated to dosage effect; other enzymes carried on trisomic chromosomes in K-562 cells did not show dosage effect. Acetylcholinesterase activity was higher in subclone K-562 (S), which shows higher expression of hemoglobin. Electrophoretic mobility of acetylcholinesterase from K-562 (S) was of fetal type.


Assuntos
Acetilcolinesterase/genética , Leucemia Mieloide Aguda/enzimologia , Acetilcolinesterase/sangue , Linhagem Celular , Bandeamento Cromossômico , Células Clonais , Feminino , Feto , Hemoglobinas/genética , Humanos , Cariotipagem , Leucemia Mieloide Aguda/genética , Gravidez
20.
Acta Haematol ; 70(6): 349-56, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6417958

RESUMO

The properties of human bone marrow fibroblastoid colonies (CFU-F) were studied in normal subjects and in patients with myeloproliferative disorders. Colony incidence was within normal values in all groups of patients analyzed except for myelodisplastic syndromes, with higher mean value. The growth rate of CFU-F is inversely related to the initial colony-forming efficiency both in normal subjects and in patients. Direct correlation between CFU-F and granulocyte-macrophage colony-forming unit (GM-CFU) was detected only in normal subjects, but lacked in patients. Higher number of CFU-F was observed in subjects with increased incidence of bone marrow megakaryocytes or peripheral blood platelets, irrespective of the underlying disorders and the platelet-derived growth-factorenhanced cloning efficiency of bone marrow fibroblasts.


Assuntos
Transtornos Mieloproliferativos/fisiopatologia , Plaquetas/fisiologia , Células da Medula Óssea , Células Cultivadas , Células Clonais/fisiologia , Fibroblastos/fisiologia , Humanos , Megacariócitos/fisiologia , Transtornos Mieloproliferativos/patologia , Fatores de Tempo
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