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2.
Br J Pharmacol ; 150(2): 209-19, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17160010

RESUMO

BACKGROUND AND PURPOSE: 5alpha,8alpha-Epidioxy-22E-ergosta-6, 22-dien-3beta-ol (ergosterol peroxide) is a major antitumour sterol produced by edible or medicinal mushrooms. However, its molecular mechanism of action has yet to be determined. Here, we examine the anticancer and anti-inflammatory effects of ergosterol peroxide. EXPERIMENTAL APPROACH: After treating RAW264.7 macrophages with LPS and purified ergosterol peroxide or ergosterol, we determined LPS-induced inflammatory cytokines, nuclear DNA binding activity of transcription factors and phosphorylation of MAP kinases (MAPKs). HT29 colorectal adenocarcinoma cells were treated with ergosterol peroxide for 5 days. To investigate the antitumour properties of ergosterol peroxide, we performed DNA microarray and RT-PCR analyses and determined the reactive oxygen species (ROS) in HT29 cells. KEY RESULTS: Ergosterol peroxide suppressed LPS-induced TNF-alpha secretion and IL-1alpha/beta expression in RAW264.7 cells. Ergosterol peroxide and ergosterol suppressed LPS-induced DNA binding activity of NF-kappaB and C/EBPbeta, and inhibited the phosphorylation of p38, JNK and ERK MAPKs. Ergosterol peroxide down-regulated the expression of low-density lipoprotein receptor (LDLR) regulated by C/EBP, and HMG-CoA reductase (HMGCR) in RAW264.7 cells. In addition, ergosterol peroxide showed cytostatic effects on HT29 cells and increased intracellular ROS. Furthermore, ergosterol peroxide induced the expression of oxidative stress-inducible genes, and the cyclin-dependent kinase inhibitor CDKN1A, and suppressed STAT1 and interferon-inducible genes. CONCLUSION AND IMPLICATION: Our results suggest that ergosterol peroxide and ergosterol suppress LPS-induced inflammatory responses through inhibition of NF-kappaB and C/EBPbeta transcriptional activity, and phosphorylation of MAPKs. Moreover, ergosterol peroxide appears to suppress cell growth and STAT1 mediated inflammatory responses by altering the redox state in HT29 cells.


Assuntos
Agaricales/química , Anti-Inflamatórios/farmacologia , Antineoplásicos/farmacologia , Ergosterol/análogos & derivados , Macrófagos/efeitos dos fármacos , Adenocarcinoma , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Quimioprevenção , Neoplasias do Colo , Ergosterol/farmacologia , Expressão Gênica/efeitos dos fármacos , Células HT29 , Humanos , Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/metabolismo , Oxirredução , Reação em Cadeia da Polimerase Via Transcriptase Reversa
3.
Abdom Imaging ; 28(6): 877-86, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14753611

RESUMO

Although ultrasonography is the method of choice for evaluating the fetus, magnetic resonance imaging (MRI) complements ultrasonography in the accurate diagnosis of fetal abnormalities. The advantages of MRI include excellent tissue contrast, a large field of view, and relative operator independence. To date, most studies on fetal MRI have focused on the fetal central nervous system and thoracic disorders. However, our experience suggests that MRI can be helpful even in evaluating fetal abdominal disorders. This pictorial essay illustrates the various MRI appearances of fetal abdominal abnormalities and discusses the indications and advantages of fetal MRI.


Assuntos
Parede Abdominal/anormalidades , Feto/anormalidades , Imageamento por Ressonância Magnética , Diagnóstico Pré-Natal , Anormalidades do Sistema Digestório/diagnóstico , Feminino , Humanos , Gravidez , Anormalidades Urogenitais/diagnóstico
4.
J Agric Food Chem ; 49(6): 3046-50, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11410007

RESUMO

Six compounds were isolated from fresh rhizomes of fingerroot (Boesenbergia pandurata Schult.) as strong antimutagens toward 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1) in Salmonella typhimurium TA98. These compounds were 2',4',6'-trihydroxychalcone (pinocembrin chalcone; 1), 2',4'-dihydroxy-6'-methoxychalcone (cardamonin; 2), 5,7-dihydroxyflavanone (pinocembrin; 3), 5-hydroxy-7-methoxyflavanone (pinostrobin; 4), (2,4,6-trihydroxyphenyl)-[3'-methyl-2'-(3' '-methylbut-2' '-enyl)-6'-phenylcyclohex-3'-enyl]methanone (5), and (2,6-dihydroxy-4-methoxyphenyl)-[3'-methyl-2'-(3' '-methylbut-2' '-enyl)-6'-phenylcyclohex-3'-enyl]methanone (panduratin A; 6). Compound 5 was a novel compound (tentatively termed 4-hydroxypanduratin A), and 1 was not previously reported in this plant, whereas 2-4 and 6 were known compounds. The antimutagenic IC(50) values of compounds 1-6 were 5.2 +/- 0.4, 5.9 +/- 0.7, 6.9 +/- 0.8, 5.3 +/- 1.0, 12.7 +/- 0.7, and 12.1 +/- 0.8 microM in the preincubation mixture, respectively. They also similarly inhibited the mutagenicity of 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). All of them strongly inhibited the N-hydroxylation of Trp-P-2. Thus, the antimutagenic effect of compounds 1-6 was mainly due to the inhibition of the first step of enzymatic activation of heterocyclic amines.


Assuntos
Aminas/análise , Compostos Heterocíclicos/antagonistas & inibidores , Especiarias/análise , Concentração Inibidora 50 , Testes de Mutagenicidade , Mutagênicos
5.
Nihon Igaku Hoshasen Gakkai Zasshi ; 61(13): 715-20, 2001 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-11766396

RESUMO

INTRODUCTION: Although fatty infiltration of liver is a benign process that generally results from chronic alcohol uptake or obesity, such lifestyle factors may lead to chronic disease. Measuring the fat concentration in liver may therefore prove useful in assessing disease status. In this study, we report the usefulness of line scan echo planar spectroscopic imaging (LSEPSI) for this problem. METHODS: Rapid successive column sampling was accomplished using orthogonal slice-selective 90 degrees and 180 degrees pulses and echo planar spectral/spatial encodings. Phantom and clinical studies of 13 patients suspected of having fatty liver were carried out with LSEPSI. Estimated fat fractions obtained with LSEPSI were compared with ultrasound findings. RESULTS: The results showed a good correlation between the actual fat content of phantoms and the estimated fat fraction obtained with LSEPSI (r = 0.95). In the clinical study, the estimated fat fraction tended to rise as the US grade of fatty liver increased. DISCUSSION: LSEPSI is largely free from T1 and T2 relaxation owing to its infinite TR and minimal T2 weighting. Thus, there is no need for relaxation analysis. In addition, the lack of phase encoding reduces motion-related ghosting artifacts. Rapid fat/water spectral quantification of liver with this technique is useful for fatty liver assessment in a clinical setting.


Assuntos
Imagem Ecoplanar/métodos , Fígado Gorduroso/diagnóstico , Adulto , Idoso , Feminino , Humanos , Fígado/metabolismo , Fígado/patologia , Masculino , Microcomputadores , Pessoa de Meia-Idade , Imagens de Fantasmas
6.
Radiographics ; 20(5): 1227-43, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10992014

RESUMO

The recent popularity of prenatal magnetic resonance (MR) imaging has been associated with the development of ultrafast MR imaging techniques such as the single-shot fast spin-echo sequence. However, the majority of previous reports have concerned the fetal central nervous system (CNS) and chest disorders. MR imaging can demonstrate non-CNS fetal anatomy and pathologic conditions clearly. With its excellent tissue contrast, MR imaging provides information that supplements that provided by ultrasonography (US), especially in cases of neck, chest, and gastrointestinal lesions. Because of its large field of view, MR imaging allows evaluation of the relationship between a large lesion and adjacent structures. MR imaging should be considered if the diagnosis of a suspected non-CNS lesion is unclear at fetal US. MR imaging plays an important complementary role to US in cases of non-CNS fetal lesions and will be further accepted for fetal imaging in the future.


Assuntos
Anormalidades Múltiplas/diagnóstico , Imagem Ecoplanar , Feto/anormalidades , Diagnóstico Pré-Natal/métodos , Abdome/anormalidades , Sistema Nervoso Central , Diagnóstico Diferencial , Feminino , Idade Gestacional , Humanos , Gravidez , Sensibilidade e Especificidade , Tórax/anormalidades , Anormalidades Urogenitais/diagnóstico
7.
Biosci Biotechnol Biochem ; 64(2): 314-8, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10737187

RESUMO

We have previously demonstrated that lactoferrin was incorporated into B lymphocytes and that a trypsin treatment for a short period reduced the number of lactoferrin molecules incorporated into B lymphocytes. An N-terminal sequence analysis revealed that the mild trypsin treatment had cleaved the three N-terminal amino acids, Gly1-Arg2-Arg3. Chemical conjugation of lost sequence analogue Gly-Arg-Arg-Gly with the mildly digested lactoferrin recovered the interaction with B lymphocytes, while conjugation of acetyl-Arg-Arg-Gly, a deamino analogue of Gly-Arg-Arg-Gly, did not recover the interaction. This shows that the N-terminal basic region containing N-terminal Gly played an important role in the interaction with B lymphocytes. Acylation of the amino groups of lactoferrin also significantly reduced the interaction with B lymphocytes, and an O-methylisourea treatment of the amino groups, which preserved the positive charge, hardly affected the interaction. These results suggest that both the N-terminal basic region and the basic characteristics of the whole molecule contributed to its interaction with B lymphocytes.


Assuntos
Linfócitos B/metabolismo , Lactoferrina/metabolismo , Sequência de Aminoácidos , Linfócitos B/química , Humanos , Lactoferrina/química
8.
Biosci Biotechnol Biochem ; 63(4): 719-25, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10361685

RESUMO

The dihydrochalcone phloretin induced apoptosis in B16 mouse melanoma 4A5 cells and HL60 human leukemia cells. Phloretin was suggested to induce apoptosis in B16 cells mainly through the inhibition of glucose transmembrane transport. The phloretin-induced apoptosis in B16 cells was inhibited by actinomycin D, Ac-YVAD-CHO caspase-1-like inhibitor, and Ac-DEVD-CHO caspase-3-like inhibitor. During the induction of apoptosis by phloretin, the expression of Bax protein in B16 cells increased and the levels of p53, Bcl-2, and Bcl-XL proteins did not change. Our results suggested that phloretin induced apoptosis through the promotion of Bax protein expression and caspases activation. On the other hand, phloretin may induce apoptosis in HL60 cells through the inhibition of protein kinase C activity because phloretin inhibited protein kinase C activity in HL60 cells more than that in B16 cells. The phloretin induced-apoptosis in HL60 cells was not inhibited by actinomycin D and the caspase-1-like inhibitor, but slightly inhibited by the caspase-3-like inhibitor. Phloretin reduced the level of caspase 3 protein in HL60 cells, but not the level of the Bcl-2 protein. Phloretin did not increase the level of Bax protein. Phloretin was suggested to induce apoptosis in HL60 cells through the inhibition of protein kinase C activity, followed by the pathway, which is different from that in B16 cells.


Assuntos
Apoptose/efeitos dos fármacos , Floretina/farmacologia , Animais , Anticorpos Monoclonais , Western Blotting , Células CHO , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/ultraestrutura , Cricetinae , Eletroforese em Gel de Ágar , Citometria de Fluxo , Células HL-60 , Humanos , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/patologia , Camundongos , Floretina/antagonistas & inibidores , Proteína Quinase C/metabolismo , Inibidores da Síntese de Proteínas/farmacologia
9.
Ann Otol Rhinol Laryngol ; 108(3): 221-6, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10086612

RESUMO

Virtual endoscopy enables computer-generated 3-dimensional visualization of a cavity by reconstructing 2-dimensional computed tomographic or magnetic resonance data. The technique has been used experimentally to study the colon, bronchi, ears, and other structures. Here, virtual laryngoscopies were created from the cross-sectional image data of 3 patients. The cases represented a normal airway, a squamous cell carcinoma of the glottic fold, and a posterior glottic stenosis. These reconstructions included extraluminal anatomy that is not typical of current virtual endoscopic techniques. The 2-dimensional computed tomographic and magnetic resonance images of the patients underwent post-processing for 3-dimensional reconstruction. The resulting models were imported into an experimental virtual endoscopy program for 1) airway lumen generation and 2) interactive viewing. Though they could not be used for biopsy, the virtual laryngoscopies provided, in a noninvasive fashion, good simulation of endoscopy. Virtual endoscopy also gave the added benefits of the ability to assess the transmural extent of disease and view the airway distal to areas of luminal compromise. This technology may well provide clinical benefit in preoperative planning, staging, and intraprocedural guidance for head and neck disease and merits further study.


Assuntos
Processamento de Imagem Assistida por Computador , Laringoscopia , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , Adulto , Feminino , Humanos , Doenças da Laringe/diagnóstico , Laringe/diagnóstico por imagem , Laringe/patologia , Masculino , Pessoa de Meia-Idade
10.
Cytotechnology ; 31(1-2): 165-72, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19003137

RESUMO

The effects of several kinds of microbial extracellular glycolipids on neurite initiation in PC12 cells were examined. Addition of mannosylerythritol lipid-A (MEL-A), MEL-B, and sophorose lipid (SL) to PC12 cells caused significant neurite outgrowth. Other glycolipids, such as polyol lipid (PL), rhamnose lipid (RL), succinoyl trehalose lipid-A (STL-A) and STL-B caused no neurite-initiation. MEL-A increased acetylcholine esterase (AChE) activity to an extent similar to nerve growth factor (NGF). However, MEL-A induced one or two long neurites from the cell body, while NGF induced many neurites. In addition, MEL-A-induced differentiation was transient, and after 48 h, percentage of cells with neurites started to decrease in contrast to neurons induced by NGF, which occurred in a time-dependent manner. MEL-A could induce neurite outgrowth after treatment of PC12 cells with an anti-NGF receptor antibody that obstructed NGF action. These results indicate that MEL-A and NGF induce differentiation of PC12 cells through different mechanisms.

11.
Biosci Biotechnol Biochem ; 62(8): 1483-7, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9757552

RESUMO

Polyphenol extract from barley bran (BPE) induced nitro blue tetrazolium (NBT) reducing activity and alpha-naphthyl butyrate esterase activity in HL60 human myeloid leukemia cells. Because BPE induced the biochemical markers of HL60 cell differentiation, we investigated the effects of proanthocyanidins isolated from BPE on the HL60 cell differentiation of HL60 cells. Prodelphinidin B-3, T1, T2, and T3 induced 26-40% NBT-positive cells and 22-32% alpha-naphthyl butyrate esterase-positive cells. Proanthocyanidins potentiated retinoic acid (all-trans-retinoic acid)-induced granulocytic and sodium butyrate-induced monocytic differentiation in HL60 cells.


Assuntos
Antocianinas/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Ácido Butírico/farmacologia , Células HL-60/efeitos dos fármacos , Hordeum/metabolismo , Proantocianidinas , Tretinoína/farmacologia , Antocianinas/isolamento & purificação , Hidrolases de Éster Carboxílico/química , Diferenciação Celular/efeitos dos fármacos , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Granulócitos/fisiologia , Células HL-60/citologia , Antagonistas dos Receptores Histamínicos/farmacologia , Humanos , Indicadores e Reagentes/química , Monócitos/fisiologia , Nitroazul de Tetrazólio/química
12.
J Magn Reson Imaging ; 8(3): 690-4, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9626888

RESUMO

The MRI features of small renal cell carcinomas (RCCs) were retrospectively reviewed and correlated with histology in 24 patients. MRI features on both T1- and T2-weighted images were classified into hypointensity, isointensity, and hyperintensity. Each tumor was pathologically classified into four types: alveolar, papillary, tubular, and cystic. These findings were correlated with MR signal intensities. Alveolar tumors showed hypointensity to isointensity on T1-weighted image and isointensity to hyperintensity on T2-weighted image. In contrast, all papillary tumors showed hypointensity on T2-weighted image. Four of six tumors with hypointensity on T2-weighted image were caused by hemosiderin deposition, hemorrhage, and necrosis. However, there were two papillary RCCs that showed hypointensity on T2-weighted image despite no hemosiderin deposition and no hemorrhage. We conclude that papillary RCC is associated with T2-hypointense appearance as well as hemosiderin deposition, hemorrhage, and necrosis.


Assuntos
Carcinoma de Células Renais/diagnóstico , Neoplasias Renais/diagnóstico , Imageamento por Ressonância Magnética , Adulto , Idoso , Carcinoma de Células Renais/classificação , Carcinoma de Células Renais/patologia , Feminino , Humanos , Rim/patologia , Neoplasias Renais/classificação , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Necrose , Estudos Retrospectivos , Sensibilidade e Especificidade
13.
Cytotechnology ; 26(1): 23-7, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22359003

RESUMO

Royal jelly was fractionated by ion-exchange chromatography and a protein (DIII protein) that had growth stimulating activity to the U-937 human myeloid cell line was obtained. The molecular weight of the DIII protein was 58 kDa on SDS-PAGE. The growth stimulating activity of the DIII protein was shown to be relatively heat and pH stable.

14.
Biosci Biotechnol Biochem ; 62(11): 2199-204, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9972240

RESUMO

The flavones apigenin and luteolin strongly inhibited the growth of HL60 cells and induced morphological differentiation into granulocytes. The flavonol quercetin inhibited the cell growth and induced a differentiation marker, i.e., NBT reducing ability. However quercetin-treated cells were not morphologically differentiated into granulocytes. The chalcone phloretin weakly induced NBT reducing ability and a marker of monocytic differentiation alpha-naphthyl butyrate esterase activity in the cells. Quercetin and phloretin appeared to induce the differentiation of HL60 cells into monocytes. The proportion of alpha-naphthyl butyrate esterase-positive cells induced by genistein was less than that of the NBT-positive cells. Some of the nuclei in genistein-treated HL60 cells morphologically changed. Genistein must have induced both granulocytic and monocytic differentiation of HL60 cells. The flavonols galangin and kaempferol, which had fewer hydroxyl group(s) in the B-ring than quercetin, and the flavanone naringenin inhibited the growth but did not induce the differentiation of HL60 cells.


Assuntos
Flavonoides/química , Granulócitos/patologia , Leucemia Mieloide/fisiopatologia , Macrófagos/patologia , Monócitos/patologia , Diferenciação Celular , Flavonoides/fisiologia , Humanos , Leucemia Mieloide/metabolismo , Leucemia Mieloide/patologia , Relação Estrutura-Atividade , Células Tumorais Cultivadas
16.
Radiology ; 205(2): 497-502, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9356635

RESUMO

PURPOSE: To investigate a method of diagnosing angiomyolipoma that contains minimal fat. MATERIALS AND METHODS: In six cases of angiomyolipoma with minimal fat, the attenuation on contrast material-enhanced and unenhanced computed tomographic (CT) images, the echogenicity on sonograms, the signal intensity on T2-weighted magnetic resonance (MR) images, and the gross configuration of the lesion were retrospectively analyzed. In 100 cases of renal cell carcinoma, the same parameters were analyzed, and results were compared with those of angiomyolipoma. RESULTS: When compared with the surrounding renal parenchyma, all six angiomyolipomas showed homogeneously high attenuation on unenhanced CT images, homogeneous enhancement on contrast-enhanced CT images, and homogeneous isoechogenicity on sonograms. Of the five angiomyolipomas examined with MR imaging, four were hypointense and one was isointense on T2-weighted images. All six angiomyolipomas protruded from the renal margin. None of the 100 renal cell carcinomas showed homogeneously high attenuation on unenhanced CT images, homogeneous enhancement on contrast-enhanced CT images, or homogeneous isoechogenicity on sonograms. CONCLUSION: In the kidney, homogeneously high attenuation on unenhanced CT images, homogeneous enhancement on contrast-enhanced CT images, and homogeneous isoechogenicity on sonograms are suggestive of angiomyolipoma that contains abundant muscle and minimal fat.


Assuntos
Angiomiolipoma/diagnóstico , Neoplasias Renais/diagnóstico , Tecido Adiposo/diagnóstico por imagem , Adulto , Idoso , Angiomiolipoma/diagnóstico por imagem , Carcinoma de Células Renais/diagnóstico , Carcinoma de Células Renais/diagnóstico por imagem , Feminino , Humanos , Neoplasias Renais/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Ultrassonografia
17.
Biosci Biotechnol Biochem ; 61(6): 1044-6, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9214770

RESUMO

A mouse hybrid-hybridoma, HH1-4-3, secreting IgG1 class bispecific antibodies to bovine lactoferrin (bLF) and horseradish peroxidase (HRPO), was established previously. The competitive enzyme-linked immunosorbent assay (ELISA) of bLF using the HH1-4-3 culture supernatant was not sensitive enough to measure bLF concentration in biological fluids. To improve the sensitivity of the competitive ELISA, we fractionated the bispecific antibodies by antigen affinity column chromatography. A column immobilized with bLF adsorbed 60% of the antibodies of the HH1-4-3 supernatant, and the amount of antibodies adsorbed on a column immobilized with HRPO was less than 5%. The competitive ELISA of bLF using the affinity purified bispecific antibodies through an HRPO-immobilized column chromatography showed a good standard curve at bLF concentrations of 10 ng/ml to 100 micrograms/ml.


Assuntos
Anticorpos Biespecíficos/imunologia , Anticorpos Monoclonais/imunologia , Ensaio de Imunoadsorção Enzimática/normas , Lactoferrina/análise , Animais , Especificidade de Anticorpos , Ligação Competitiva , Bovinos , Fracionamento Químico , Cromatografia de Afinidade , Eletroforese em Gel de Poliacrilamida , Peroxidase do Rábano Silvestre/química , Peroxidase do Rábano Silvestre/imunologia , Hibridomas , Lactoferrina/química , Lactoferrina/imunologia , Camundongos , Sensibilidade e Especificidade
18.
Biosci Biotechnol Biochem ; 61(4): 609-14, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9145519

RESUMO

The biological activities of 7 microbial extracellular glycolipids including mannosylerythritol lipid (MEL)-A, MEL-B, polyol lipid (PL), rhamnolipid (RL), sophorose lipid (SL), succinoyl trehalose lipid (STL)-1, and STL-3 were investigated. All glycolipids except for RL were found to induce cell differentiation instead of cell proliferation in the human promyelocytic leukemia cell line HL60. To identify the differentiation direction of the induced cells, the leukocyte esterase activities were cytologically investigated, and the results showed that MEL-A, MEL-B, and PL induced HL60 to differentiate into granulocytes, while SL, STL-1, and STL-3 induced differentiation into monocytes. The 6 effective glycolipids also increased nitroblue tetrazolium (NBT) reducing ability, which is a common differentiation-associated characteristic in monocytes and granulocytes. Furthermore, it was also observed that these 6 glycolipids inhibited the activity of phospholipid- and Ca(2+)-dependent protein kinase. Additionally, the 6 effective glycolipids also induced the human myelogenous leukemia cell line K562 and the human basophilic leukemia cell line KU812 to differentiate into monocytes, granulocytes, and megakaryocytes.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Glicolipídeos/farmacologia , Proteína Quinase C/antagonistas & inibidores , Células HL-60 , Humanos , Leucemia Promielocítica Aguda/enzimologia , Leucemia Promielocítica Aguda/metabolismo , Leucemia Promielocítica Aguda/patologia , Nitroazul de Tetrazólio/metabolismo
19.
Lipids ; 32(3): 263-71, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9076663

RESUMO

Microbial extracellular glycolipids, succinoyl trehalose lipid (STL), and mannosylerythritol lipid (MEL) inhibited the growth of a human promyelocytic leukemia cell line, HL60, and induced their morphological changes. The results of specific and nonspecific leukocyte esterase activities showed that STL induced monocytotic differentiation while MEL induced granulocytic differentiation. STL and MEL markedly increased common differentiation-associated characteristics in monocytes and granulocytes, such as nitroblue tetrazolium (NBT) reducing ability, expression of Fc receptors, and phagocytic activities in HL60 cells, respectively. Neither sugar moieties nor fatty acids in the free form, the individual components of STL and MEL, were effective at inducing the differentiation of HL60 cells. The induction of differentiation was not due to surface activities of STL and MEL on the basis of the complete ineffectiveness of the analogues tested. The composition of cell surface glycosphingolipids (GSL) changed such that the GM3/LacCer ratio increased in STL-treated cells, whereas it decreased in MEL-treated cells. HL60 cells treated with STL and MEL exhibited a significant decrease in the activity of the intracellular phospholipid- and Ca(2+)-dependent protein kinase (protein kinase C). Furthermore, the serine/threonine phosphorylations in intact HL60 cells were clearly inhibited by the presence of GM3 and MEL, but not by LacCer and STL. These results suggest that the differentiation-inducing activity of STL and MEL is not due to a simple detergent-like effect but due to a specific action on the plasma membrane. The inhibitory effect of STL on protein kinase activity was through increasing GM3, but MEL had a direct inhibitory effect.


Assuntos
Glicolipídeos/química , Glicolipídeos/farmacologia , Células HL-60/patologia , Candida/metabolismo , Hidrolases de Éster Carboxílico/efeitos dos fármacos , Hidrolases de Éster Carboxílico/metabolismo , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Ácidos Graxos/farmacologia , Glicoesfingolipídeos/química , Células HL-60/citologia , Células HL-60/efeitos dos fármacos , Humanos , Monócitos , Fosforilação/efeitos dos fármacos , Proteína Quinase C/efeitos dos fármacos , Proteína Quinase C/metabolismo , Proteínas/efeitos dos fármacos , Proteínas/metabolismo , Rhodococcus/metabolismo , Succinatos/química , Succinatos/farmacologia , Ácido Succínico , Trealose/química , Trealose/farmacologia
20.
J Comput Assist Tomogr ; 21(1): 82-8, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9022774

RESUMO

PURPOSE: Our goal was to evaluate several fast MR strategies for monitoring ethanol distributions so that percutaneous ethanol injection might be guided with MRI. METHOD: Fast RF spoiled GRE sequences (SPGR) and T2-weighted rapid acquisition with relaxation enhancement (RARE) sequences with and without spectroscopic-quality water suppression techniques were assessed for their ability to depict the distribution of injected ethanol in ex vivo pig liver. A line scan Carr-Purcell-Meiboom-Gill spectroscopic imaging sequence was used to validate observations and measure spectral relaxation characteristics of the ethanol signal in liver. Injected deuterated ethanol was also tested as an alternative possibility to depict the distribution of ethanol. RESULTS: The water-suppressed T2-weighted RARE sequence depicted the distribution of ethanol better than other sequences. Deuterated ethanol appeared as a signal void on all sequences. CONCLUSION: Water-suppressed T2-weighted RARE sequences could be useful to rapidly monitor MR-guided PEI.


Assuntos
Etanol/administração & dosagem , Fígado/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Animais , Etanol/farmacocinética , Técnicas In Vitro , Injeções , Fígado/metabolismo , Suínos
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