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1.
Insect Mol Biol ; 27(2): 154-165, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29096051

RESUMEN

Despite possessing a limited number of neurones compared to vertebrates, honeybees show remarkable learning and memory performance, an example being 'dance communication'. In this phenomenon, foraging honeybees learn the location of a newly discovered food source and transmit the information to nestmates by symbolic abdomen vibrating behaviour, leading to navigation of nestmates to the new food source. As an initial step toward understanding the detailed molecular mechanisms underlying the sophisticated learning and memory performance of the honeybee, we focused on the neural immediate early genes (IEGs), which are specific genes quickly transcribed after neural activity without de novo protein synthesis. Although these have been reported to play an essential role in learning and memory processes in vertebrates, far fewer studies have been performed in insects in this regard. From RNA-sequencing analysis and subsequent assays, we identified three genes, Src homology 3 (SH3) domain binding kinase, family with sequence similarity 46 and GB47136, as novel neural IEGs in the honeybee. Foragers and/or orientating bees, which fly around their hives to memorize the positional information, showed induced expression of these IEGs in the mushroom body, a higher-order centre essential for learning and memory, indicating a possible role for the novel IEGs in foraging-related learning and memory processes in the honeybee.


Asunto(s)
Abejas/fisiología , Genes Inmediatos-Precoces/genética , Proteínas de Insectos/genética , Memoria , Animales , Abejas/genética , Conducta Alimentaria , Proteínas de Insectos/metabolismo , Aprendizaje
2.
Heredity (Edinb) ; 116(2): 135-45, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26328757

RESUMEN

Ommochromes are major insect pigments involved in coloration of compound eyes, eggs, epidermis and wings. In the silkworm Bombyx mori, adult compound eyes and eggs contain a mixture of the ommochrome pigments such as ommin and xanthommatin. Here, we identified the gene involved in ommochrome biosynthesis by positional cloning of B. mori egg and eye color mutant pink-eyed white egg (pe). The recessive homozygote of pe has bright red eyes and white or pale pink eggs instead of a normal dark coloration due to the decrease of dark ommochrome pigments. By genetic linkage analysis, we narrowed down the pe-linked region to ~258 kb, containing 17 predicted genes. RNA sequencing analyses showed that the expression of one candidate gene, the ortholog of Drosophila haem peroxidase cardinal, coincided with egg pigmentation timing, similar to other ommochrome-related genes such as Bm-scarlet and Bm-re. In two pe strains, a common missense mutation was found within a conserved motif of B. mori cardinal homolog (Bm-cardinal). RNA interference-mediated knockdown and transcription activator-like effector nuclease (TALEN)-mediated knockout of the Bm-cardinal gene produced the same phenotype as pe in terms of egg, adult eye and larval epidermis coloration. A complementation test of the pe mutant with the TALEN-mediated Bm-cardinal-deficient strain showed that the mutant phenotype could not be rescued, indicating that Bm-cardinal is responsible for pe. Moreover, knockdown of the cardinal homolog in Tribolium castaneum also induced red compound eyes. Our results indicate that cardinal plays a major role in ommochrome synthesis of holometabolous insects.


Asunto(s)
Bombyx/genética , Proteínas de Insectos/genética , Fenotiazinas/metabolismo , Pigmentación/genética , Animales , Clonación Molecular , Ojo , Femenino , Técnicas de Inactivación de Genes , Genes de Insecto , Prueba de Complementación Genética , Ligamiento Genético , Proteínas de Insectos/metabolismo , Larva , Masculino , Óvulo , Fenotipo , Filogenia , Interferencia de ARN , Tribolium/genética
3.
J Periodontal Res ; 48(2): 235-42, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22957762

RESUMEN

OBJECTIVE AND BACKGROUND: Gingival epithelium protects against bacterial infection by producing antimicrobial peptides such as calprotectin. Calprotectin consists of proteins S100A8 and S100A9. Although in vitro assay has shown that neutrophils and gingival epithelial cells express calprotectin, the expression of S100A8 and S100A9 and colocalization of both S100 proteins in gingival tissue in vivo are not fully understood. The aim of this study was to investigate the distribution of S100A8 and S100A9 expression in gingival epithelium of mice in the presence and absence of infection. MATERIALS AND METHODS: A quantitative analysis of S100A8 and S100A9 mRNA in junctional epithelium (JE) and oral gingival epithelium (OGE) of both germ-free mice and conventional mice was performed using laser microdissection and real-time polymerase chain reaction (PCR). Confirmation of S100A8 and S100A9 mRNA expression in the JE was conducted by fluorescent immunohistochemistry. RESULTS: Real-time PCR analysis indicated that S100A8 and S100A9 expressions were mainly detected in JE and only slightly or not detected in OGE. Levels of both S100A8 and S100A9 mRNA expression in JE of conventional mice were significantly higher than those in JE of germ-free mice. Additionally, fluorescent immunohistochemistry showed that S100A8 expression was observed in the JE of both conventional and germ-free mice, whereas S100A9 was expressed in the JE of conventional but not germ-free mice. CONCLUSION: S100A8 protein is expressed in JE cells of mice in the presence and in the absence of infection with oral bacteria. S100A9 expression in JE cells in the presence of microflora is significantly increased compared with the absence of microflora, which suggests that S100A9 expression may be induced by infection of microflora. The production of calprotectin in gingival epithelial cells may be mediated through S100A9 induction by bacterial infection.


Asunto(s)
Calgranulina A/análisis , Calgranulina B/análisis , Citocinas/análisis , Encía/anatomía & histología , Animales , Inserción Epitelial/anatomía & histología , Células Epiteliales/citología , Epitelio/anatomía & histología , Femenino , Técnica del Anticuerpo Fluorescente , Vida Libre de Gérmenes , Encía/citología , Encía/microbiología , Terapia por Láser , Ratones , Ratones Endogámicos ICR , Microdisección , Neutrófilos/citología , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores de Quimiocina/análisis
4.
Rev Sci Instrum ; 87(2): 02B135, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26932017

RESUMEN

A filament driven multi-cusp negative ion source has been developed for proton cyclotrons in medical applications. In Cs-free operation, continuous H(-) beam of 10 mA and D(-) beam of 3.3 mA were obtained stably at an arc-discharge power of 3 kW and 2.4 kW, respectively. In Cs-seeded operation, H(-) beam current reached 22 mA at a lower arc power of 2.6 kW with less co-extracted electron current. The optimum gas flow rate, which gives the highest H(-) current, was 15 sccm in the Cs-free operation, while it decreased to 4 sccm in the Cs-seeded operation. The relationship between H(-) production and the design/operating parameters has been also investigated by a numerical study with KEIO-MARC code, which gives a reasonable explanation to the experimental results of the H(-) current dependence on the arc power.


Asunto(s)
Aniones , Cesio , Ciclotrones , Deuterio
5.
Rev Sci Instrum ; 87(4): 043503, 2016 04.
Artículo en Inglés | MEDLINE | ID: mdl-27131670

RESUMEN

In TST-2 Ohmic discharges, local current is measured using a Rogowski probe by changing the angle between the local magnetic field and the direction of the hole of the Rogowski probe. The angular dependence shows a peak when the direction of the hole is almost parallel to the local magnetic field. The obtained width of the peak was broader than that of the theoretical curve expected from the probe geometry. In order to explain this disagreement, we consider the effect of sheath in the vicinity of the Rogowski probe. A sheath model was constructed and electron orbits were numerically calculated. From the calculation, it was found that the electron orbit is affected by E × B drift due to the sheath electric field. Such orbit causes the broadening of the peak in the angular dependence and the dependence agrees with the experimental results. The dependence of the broadening on various plasma parameters was studied numerically and explained qualitatively by a simplified analytical model.

6.
FEBS Lett ; 333(3): 257-60, 1993 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-8224189

RESUMEN

The three-dimensional solution structure of the colicin E3 immunity protein (84 residues) was determined by distance geometry calculations. The hydrophilic side of a four-stranded antiparallel beta-sheet constitutes a part of the surface of the protein, and two loops lie on the hydrophobic side of the sheet. All the three specificity-determining residues, which are included in the center of the beta-sheet, display their side groups on the protein surface.


Asunto(s)
Proteínas Bacterianas/química , Colicinas/antagonistas & inhibidores , Proteínas de Escherichia coli , Estructura Secundaria de Proteína , Secuencia de Aminoácidos , Sitios de Unión , Escherichia coli , Espectroscopía de Resonancia Magnética/métodos , Modelos Moleculares
7.
Anal Chem ; 72(21): 5290-4, 2000 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-11080878

RESUMEN

Calix[4]arene derivatives incorporating pi-coordinate substituents such as allyl, benzyl, and propargyl groups were designed as soft neutral carriers for silver ion sensors. Most of all, tert-butylcalix[4]arene tetra(allyl ether) is an excellent neutral carrier for plasticized poly(vinyl chloride)-membrane silver ion-selective electrodes. The ion sensors showed high silver ion selectivity over alkali metal ions and also good selectivity against other soft metal ions such as lead and mercury(II) ions. The electrode potential response was as rapid as that for neutral-carrier-type alkali metal ion electrodes due to the soft interaction between pi-coordinate substituents and silver ion, which was elucidated by 1H NMR spectroscopy.

8.
Neuroscience ; 94(2): 629-36, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10579223

RESUMEN

A putative transcription factor induced in vitro by glial cell line-derived neurotrophic factor (GDNF) and transforming growth factor-beta was recently cloned and characterized [Yajima S. et al. (1997) J. Neurosci. 17, 8657-8666]. The messenger RNA of this protein, termed murine GDNF-inducible transcription factor (mGIF, hereafter referred to as GIF), is localized within cortical and hippocampal regions of brain, suggesting that GIF might be regulated by perturbations of these brain regions. In an effort to learn more about the role of GIF in vivo, we examined GIF messenger RNA in the brains of rats treated with the glutamatergic agonist kainic acid. This treatment is known to induce seizures and alter the messenger RNA expression of several growth factors, including GDNF, in several brain regions. Rats were given intraperitoneal saline (1 ml/kg) or kainic acid (15 mg/kg) and were killed at various time-points for in situ hybridization of brain sections with a GIF messenger RNA riboprobe. In saline-treated rats, GIF messenger RNA was present at low levels in cerebral cortex, hippocampus and hippocampal remnants such as the taenia tecta. Kainic acid treatment induced robust increases in GIF messenger RNA in several brain regions, including cerebral cortex, hippocampus, caudate-putamen, nucleus accumbens, and several nuclei of the amygdala and hypothalamus. Most brain regions showed the greatest increase in GIF messenger RNA 4-6 h after kainic acid administration and a return towards normal levels at 48 h. The CA3 region of hippocampus, however, showed a more rapid increase in GIF messenger RNA that was also evident 48 h after kainic acid administration. These results demonstrate that GIF messenger RNA can be regulated in vivo, and that this novel factor warrants further study as a central mediator of GDNF and perhaps other neurotrophic factors.


Asunto(s)
Encéfalo/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Ácido Kaínico/farmacología , Factores de Crecimiento Nervioso , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/farmacología , Fármacos Neuroprotectores/farmacología , Factores de Transcripción/genética , Transcripción Genética/efectos de los fármacos , Animales , Núcleo Caudado/metabolismo , Lóbulo Frontal/metabolismo , Factor Neurotrófico Derivado de la Línea Celular Glial , Hipocampo/metabolismo , Masculino , Ratones , Núcleo Accumbens/metabolismo , Especificidad de Órganos , Putamen/metabolismo , ARN Mensajero/genética , Ratas , Ratas Sprague-Dawley , Factor de Crecimiento Transformador beta/farmacología
9.
Cancer Lett ; 126(2): 173-8, 1998 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-9585063

RESUMEN

The present study was carried out in order to estimate a usefulness of vitamin E against 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-induced lung tumorigenesis in mice. Feeding high doses of vitamin E suppressed the NNK-induced elevation of the activity of ornithine decarboxylase, a key enzyme of polyamine biosynthesis, in the lungs of mice at 4 weeks after injection. In contrast, the vitamin elevated the NNK-induced decrease of the activity of spermidine/spermine N1-acetyltransferase, a key enzyme of polyamine biodegradation. In conjugation with these events, the NNK-increased level of proliferating nuclear cell antigen as a marker of cell proliferation was suppressed by vitamin E treatment. Also, the supply of high doses of vitamin E suppressed NNK-induced lung tumorigenesis in mice. These results suggest that vitamin E inhibits the development of lung tumors in mice treated with NNK, partly due to the regulation of polyamine metabolism.


Asunto(s)
Neoplasias Pulmonares/metabolismo , Poliaminas/metabolismo , Antígeno Nuclear de Célula en Proliferación/efectos de los fármacos , Vitamina E/farmacología , Animales , Arilamina N-Acetiltransferasa/efectos de los fármacos , Arilamina N-Acetiltransferasa/metabolismo , Carcinógenos , Activación Enzimática , Femenino , Neoplasias Pulmonares/inducido químicamente , Neoplasias Pulmonares/enzimología , Ratones , Ratones Endogámicos A , Proteínas de Neoplasias/efectos de los fármacos , Proteínas de Neoplasias/metabolismo , Nitrosaminas , Ornitina Descarboxilasa/efectos de los fármacos , Ornitina Descarboxilasa/metabolismo , Antígeno Nuclear de Célula en Proliferación/metabolismo
10.
Cancer Lett ; 155(2): 115-20, 2000 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-10822125

RESUMEN

The present study was undertaken to estimate the effect of 6-methylthiohexyl isothiocyanate (6MHITC) isolated from Wasabia japonica (wasabi) pretreatment on 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone(NNK)-induced lung tumorigenesis in mice. Pretreatment with 6MHITC for 4 consecutive days at a daily dose of 5 micromol significantly inhibited NNK-induced O(6)-methylguanine formation in lungs at 4 h after the injection. In conjugation with this inhibitory effect, 6MHITC suppressed the increase in proliferating nuclear cell antigen level as well as ornithine decarboxylase activity at a promotion stage of NNK-induced lung tumorigenesis. Finally, this treatment of 6MHITC suppressed the NNK-induced lung tumorigenesis in mice. These results suggest that 6MHITC inhibits the development of lung tumors in mice treated with NNK, due to the suppression of initiation stage.


Asunto(s)
Carcinógenos , Isotiocianatos/farmacología , Neoplasias Pulmonares/inducido químicamente , Nitrosaminas , Extractos Vegetales/farmacología , Animales , Peso Corporal/efectos de los fármacos , Femenino , Guanina/análogos & derivados , Guanina/metabolismo , Immunoblotting , Neoplasias Pulmonares/prevención & control , Ratones , Ornitina Descarboxilasa/metabolismo , Antígeno Nuclear de Célula en Proliferación/biosíntesis , Especias
11.
Biochem Pharmacol ; 41(3): 453-6, 1991 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-1994902

RESUMEN

The effects of sodium 2-[5-(4-chlorophenyl)pentyl]oxirane-2-carboxylate (POCA), a potent inhibitor of carnitine palmitoyltransferase I, on fatty acid oxidation were investigated using fibroblasts from control subjects and from patients with peroxisomal disorders. [1-14C]Palmitate oxidation was inhibited by 8% of the control value when 15 microM POCA was added to the medium. The inhibition by POCA was significantly (P less than 0.05) stronger in fibroblasts from patients with Zellweger syndrome or with neonatal adrenoleukodystrophy, in which peroxisomes and peroxisomal beta-oxidation enzymes were absent. However, the inhibition in fibroblasts from patients with X-linked adrenoleukodystrophy, in which a specific defect of peroxisomal lignoceroyl-CoA synthetase was speculated, was similar to that in the controls. [1-14C]Lignocerate oxidation was not influenced by the addition of POCA, in samples from the controls and from the patients. These results indicate that peroxisomes account for a small but demonstrable proportion of palmitate oxidation, and add new evidence to the concept that lignocerate is oxidized exclusively in the peroxisomes. Our findings also support the hypotheses that the activity of palmitoyl-CoA synthetase and the enzymes of beta-oxidation cycle in peroxisomes are normal in patients with X-linked adrenoleukodystrophy and that a specific defect of lignoceroyl-CoA synthetase is responsible for the accumulation of very long chain fatty acids in these patients.


Asunto(s)
Compuestos Epoxi/farmacología , Ácidos Grasos/metabolismo , Microcuerpos/metabolismo , Adrenoleucodistrofia/diagnóstico , Células Cultivadas/efectos de los fármacos , Humanos , Lactante , Recién Nacido , Oxidación-Reducción/efectos de los fármacos , Palmitatos/metabolismo , Síndrome de Zellweger/diagnóstico
12.
Biochem Pharmacol ; 61(9): 1177-81, 2001 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-11301052

RESUMEN

It is known that vitamin E inhibits tumor cell growth in vitro irrespective of its antioxidative effect. However, it is unclear whether the effect in vitro can be applied to the in vivo situation. In order to address this question, we estimated if alpha-tocopheryloxybutyric acid (TSE), a non-antioxidative vitamin E derivative in vivo, could inhibit cell proliferation during the tumorigenic process of lung in mice treated with 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), the most potent carcinogen among tobacco-specific nitrosamines. TSE administration suppressed the labeling index of the proliferating cell nuclear antigen, a marker of cell proliferation at a promotion phase of NNK-induced lung tumorigenesis in mice. Similarly, TSE administration inhibited the elevation of ornithine decarboxylase (ODC) activity and its mRNA at the promotion phase. Of four transcription factors contributing to ODC induction, the change in the level of the c-Myc/Max-consensus oligonucleotide complex was only proportional to the change in ODC mRNA level. These results suggest that vitamin E can inhibit cell proliferation linked with ODC induction at the promotion phase of lung tumorigenesis irrespective of its antioxidative effect and that modulation of the transactivation of the c-Myc/Max complex for the ODC gene by TSE in part contributes to the suppression of ODC induction.


Asunto(s)
Expresión Génica/efectos de los fármacos , Ornitina Descarboxilasa/biosíntesis , Vitamina E/análogos & derivados , Vitamina E/farmacología , Animales , Antineoplásicos/farmacología , Pruebas de Carcinogenicidad , División Celular/efectos de los fármacos , Femenino , Silenciador del Gen , Neoplasias Pulmonares/inducido químicamente , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Ratones , Ornitina Descarboxilasa/genética , Transcripción Genética/efectos de los fármacos
13.
Brain Res Mol Brain Res ; 69(2): 281-5, 1999 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-10366749

RESUMEN

The effects of chronic corticosterone administration and adrenalectomy on the expression of brain dopamine receptors were studied in rats. In situ hybridization and receptor binding autoradiography were carried out to determine D1, D2 and D3 receptor expression in dorsal and ventral striata. Except for down-regulation of D2 mRNA in dorsal striatum after 2 week corticosterone treatment, no other significant changes were detected. In addition, the transcriptional regulation of D1 and D2 gene promoters by glucocorticoids was studied in neuroblastoma cell lines using transient transfections. While a small segment of the D2-promoter could be activated three-fold by dexamethasone, large fragments of neither D1 or D2 promoters were regulated by this treatment. Glucocorticoids do not appear to have direct overall effects on striatal dopamine receptor expression. The observed down-regulation of D2 receptor mRNA in the dorsal striatum in vivo is likely secondary to increased striatal dopamine release induced by corticosterone.


Asunto(s)
Glándulas Suprarrenales/fisiología , Cuerpo Estriado/efectos de los fármacos , Corticosterona/farmacología , Receptores Dopaminérgicos/efectos de los fármacos , Adrenalectomía , Animales , Células Cultivadas , Cuerpo Estriado/metabolismo , Masculino , Proteínas del Tejido Nervioso/biosíntesis , Regiones Promotoras Genéticas , Ratas , Ratas Sprague-Dawley , Receptores Dopaminérgicos/genética , Transcripción Genética
14.
Bone Marrow Transplant ; 28(1): 83-7, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11498749

RESUMEN

We describe the successful treatment of a 20-year-old patient with chronic granulomatous disease (CGD), by unrelated bone marrow transplantation (UBMT). The patient is relatively old compared to other CGD patients treated with BMT. He had had repeated serious infections from early childhood and was diagnosed as CGD, gp91-phox deficiency. Prolonged antibiotic-resistant pneumonitis worsened when the patient was 18 years old. In addition, he suffered Aspergillus osteomyelitis and acute renal failure due to amphotericin B. He received 94 granulocyte transfusions from 94 adult donors and the infections gradually improved. In September 1998, at 20 years of age, he underwent UBMT from an HLA 6 antigen-matched male donor, with CY and TBI conditioning. He received MTX and CsA as prophylaxis against GVHD. No serious complications occurred and rapid engraftment was achieved. Acute GVHD (grade 2, at day 19) and chronic GVHD (limited, at day 192) occurred. However, both were easily controlled. The patient is alive and well with no late rejection 26 months after UBMT.


Asunto(s)
Trasplante de Médula Ósea/inmunología , Enfermedad Granulomatosa Crónica/terapia , Osteomielitis/etiología , Neumonía/etiología , Adulto , Aspergilosis/etiología , Aspergilosis/terapia , Terapia Combinada , Manejo de la Enfermedad , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Enfermedad Granulomatosa Crónica/complicaciones , Antígenos HLA/inmunología , Humanos , Imagen por Resonancia Magnética , Masculino , Osteomielitis/microbiología , Osteomielitis/terapia , Neumonía/terapia , Donantes de Tejidos
15.
DNA Cell Biol ; 17(5): 471-9, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9628590

RESUMEN

The rat D2 dopamine receptor gene is transcribed from a TATA-less promoter that has an initiator-like sequence and several putative Sp1 binding sites. We previously reported that a negative modulator is located between nucleotides -116 and -76 (D2Neg-B) in this gene and that Sp1 as well as another unknown factor bind to this region (Minowa et al., J. Biol. Chem. 269, 11656, 1994). In the present investigation employing the in situ filter detection method, we identified this factor as Sp3. Anti-Sp3 antiserum used in gel-shift assays also revealed that Sp3 binds to the D2Neg-B sequence. Cotransfection of Drosophila Schneider's SL2 cells with Sp3 or Sp1 expression plasmids in the presence of CAT reporter plasmids containing D2 promoter regions demonstrated that Sp1 increased CAT activity in a dose-dependent manner, whereas Sp3, either alone or in the presence of Sp1, failed to activate or repress transcription. On the other hand, using the TATA-containing reporter plasmid BCAT-2, Sp3 coexpression significantly repressed Sp1-induced trans-activation, although Sp3 alone was ineffective. Thus, the transcriptional activity of Sp3 is dependent on the promoter context, and the negative regulation of D2 gene expression appears quite complex and may not depend simply on known DNA-protein interactions involving only Sp1 and Sp3.


Asunto(s)
Regulación de la Expresión Génica , Receptores de Dopamina D2/biosíntesis , Receptores de Dopamina D2/genética , Factor de Transcripción Sp1/fisiología , Secuencia de Aminoácidos , Animales , Sitios de Unión/genética , Clonación Molecular , ADN/metabolismo , ADN Complementario/aislamiento & purificación , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/fisiología , Regulación de la Expresión Génica/efectos de los fármacos , Ratones , Datos de Secuencia Molecular , Familia de Multigenes , Neuroblastoma , Especificidad de Órganos/genética , Ratas , Factor de Transcripción Sp3 , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Factores de Transcripción/fisiología , Células Tumorales Cultivadas
16.
DNA Cell Biol ; 16(11): 1267-75, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9406999

RESUMEN

The D1A dopamine receptor gene consists of a short, noncoding exon 1 separated from a longer coding exon 2 by a small intron. Recently, we found that in addition to its original TATA-less promoter located upstream of exon 1, the human D1A dopamine receptor gene is transcribed in neural cells from a second strong promoter located in its intron. In the present study, we addressed the possibility that these two promoters are used for the tissue-specific regulation of the D1A gene in neuronal and renal cells. Reverse transcription polymerase chain reaction revealed that D1A transcripts in the kidneys of humans and rats lack exon 1. Transient transfection analysis of these two promoters in D1A-expressing cells indicated that the upstream promoter has no detectable activity in the opossum kidney (OK) cell line, in contrast to its strong activity in two neuronal cell lines, SK-N-MC and NS20Y. On the other hand, the D1A intron promoter showed transcriptional activity both in OK cells and in neuronal cells. The activator sequence AR1, which enhances transcription from the upstream promoter in SK-N-MC and NS20Y cells, could not activate this promoter in OK cells. In addition, no protein binding to AR1 could be detected by gel mobility shift assay using nuclear extracts from either OK cells or from rat kidney tissue. These findings indicate that the differential expression of short and long D1A transcripts is due, at least in part, to the tissue-specific expression of the activator protein binding to AR1 driving transcription from the upstream promoter. Absence of this activator protein accounts for the nonfunctional D1A upstream promoter in the kidney.


Asunto(s)
Química Encefálica , Riñón/química , Regiones Promotoras Genéticas , Receptores de Dopamina D1/genética , Animales , Secuencia de Bases , Línea Celular , Exones , Humanos , Intrones , Datos de Secuencia Molecular , Zarigüeyas , Reacción en Cadena de la Polimerasa , Ratas , Transcripción Genética , Células Tumorales Cultivadas
17.
Neurosci Res ; 34(4): 225-34, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10576545

RESUMEN

Transcription in the human and rat D1A dopamine receptor genes proceeds from two distinct promoters in neuronal cells while only the downstream intronic promoter is active in renal cells. To investigate the utility of these promoters in the brain cell-specific expression of transgenes, we now studied the 5' flanking region of the murine D1A gene. We confirmed the presence of two functional promoters utilized for the tissue-specific regulation of this gene similar to its human and rat homologues. The cloned 1.4-kb genomic fragment spans nucleotides - 967 to + 384 relative to the first ATG codon and includes intron 1 between bases -534 to -420. Transient expression analyses using various chloramphenicol acetyltransferase constructs revealed that the murine D1A upstream promoter fused with the human D1A gene activator sequence ActAR1 has potent transcriptional activity in a D1A-expressing neuronal cell line but not in other cell lines tested including renal (OK cells), glial (C6) and hepatic (HepG2), suggesting that this hybrid construct harbors neural cell-specific elements. The availability of potent regulatory DNA cassettes harboring the murine D1A gene promoter could aid testing the neuronal-specific expression of transgenes in vivo.


Asunto(s)
ADN/genética , Genes Reguladores/genética , Neuronas/metabolismo , Regiones Promotoras Genéticas/genética , Receptores de Dopamina D1/genética , Secuencia de Aminoácidos/genética , Animales , Secuencia de Bases/genética , Encéfalo/metabolismo , Clonación Molecular , ADN/metabolismo , Humanos , Isomerismo , Riñón/metabolismo , Ratones , Datos de Secuencia Molecular , ARN Mensajero/genética , Ratas , Transcripción Genética/fisiología , Transfección , Células Tumorales Cultivadas
18.
Int J Hematol ; 54(3): 241-9, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1747459

RESUMEN

A retrospective clinicopathological study was performed on 149 patients who developed malignant lymphoma at under 20 years of age and were diagnosed and treated at the National Cancer Center Hospital between 1962-1986. Using the Japanese Lymphoma Study Group classification (and Working Formulation), we reclassified the 84 evaluable tissue specimens as follows: follicular large and mixed lymphoma (two cases), diffuse lymphoblastic lymphoma (40 cases), Burkitt's lymphoma (small noncleaved, SNC) (12 cases), diffuse large and mixed cell lymphoma (25 cases), and unclassified (five cases). The age of the patients ranged from 6 months to 20 years, with a median of 11 years. The clinical characteristics were found to depend upon the histological diagnosis, as reported previously. To evaluate the influence of various clinical and morphological parameters on survival, univariate analysis was performed for each histological subtype. In lymphoblastic lymphoma, patients with a mediastinal mass had significantly earlier development of leukemic conversion and a shorter survival than patients without a mass. Because of the small number of patients and their short survival, no significant prognostic factors were found in Burkitt's lymphoma (SNC). In large and mixed cell lymphoma, response to therapy was the most significant prognostic factor. As therapy became more intense and systematic throughout the study period, the complete remission rate and survival improved steadily. Autopsy findings confirmed that lymphoblastic lymphoma and Burkitt's lymphoma (SNC) spread systemically earlier than large and mixed cell lymphoma.


Asunto(s)
Linfoma no Hodgkin/epidemiología , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Ganglios Linfáticos/patología , Linfoma no Hodgkin/clasificación , Linfoma no Hodgkin/mortalidad , Linfoma no Hodgkin/patología , Linfoma no Hodgkin/terapia , Masculino , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia
19.
Int J Hematol ; 70(4): 268-77, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10643153

RESUMEN

The purpose of this study was to investigate the biological characteristics and prognostic value of in vitro three-drug resistance to prednisolone, L-asparaginase, and vincristine in childhood acute lymphoblastic leukemia (ALL). We carried out in vitro tests with a 4-day culture and a methyl-thiazol-tetrazolium assay on bone marrow samples from 209 children newly diagnosed with ALL. After testing the resistance of leukemic cells to 14 drugs, we classified the patients into two groups according to their sensitivity to three drugs (prednisolone, L-asparaginase, and vincristine) used in remission induction therapy. The three-drug resistant group (RR: sensitive to no drugs or to one drug) correlated with both short-term and long-term treatment failure. Three-year event-free survival (95% confidence interval) for the sensitive group (SS: sensitive to two or three drugs) was 0.813 (0.773-0.853) and that of the RR group was 0.616 (0.569-0.669) (P = 0.0001). Univariate analysis showed that Philadelphia-chromosome (Ph1) positivity and immunophenotype of mixed lineage were also prognostic factors in the 209 patients. The prognosis of the SS/RR drug resistance profile within 14 Ph1 patients was marginally significant (P = 0.062). Multivariate Cox regression analysis showed that Ph1 was an overwhelmingly adverse factor in event-free survival, with a relative hazard of 5.37 (2.57-11.21, P < 0.0001), followed by RR, with a relative hazard of 2.98 (1.69-5.25, P = 0.0001). Furthermore, we clarified the characteristics of the RR group by examination of the pattern of drug resistance to other drugs in comparison with the SS group. The leukemic cells of RR patients were more resistant than those of SS patients (P < 0.0001) to all the drugs tested, with resistance ratios of 1.6 to 13.1 (mean 3.4). In conclusion, in vitro three-drug resistance at the initial stage is an important independent predictor of treatment failure for both induction response and long-term outcome in childhood ALL.


Asunto(s)
Asparaginasa/farmacología , Resistencia a Múltiples Medicamentos/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Prednisolona/farmacología , Vincristina/farmacología , Adolescente , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/metabolismo , Técnicas de Cultivo de Célula , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Cromosoma Filadelfia , Pronóstico , Estudios Retrospectivos
20.
J Gastroenterol ; 35(4): 299-303, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10777161

RESUMEN

We report a case of pseudomembranous colitis that developed in a patient with liver cirrhosis during anti-tuberculosis therapy with rifampicin and isoniazid. The association between rifampicin and pseudomembranous colitis has been controversial; this report, however, supports the association. Colonoscopy performed 3 days after the onset of the pseudomembranous colitis revealed only reddish patches and a few aphthoid lesions, but 4 days later pseudomembranes were apparent. The pseudomembranous colitis was successfully controlled by discontinuation of the anti-tuberculosis agents, along with the administration of lactic acid bacteria, without vancomycin or metronidazole. Possible predisposing factors for the development of pseudomembranous colitis in this patient are also discussed.


Asunto(s)
Antibióticos Antituberculosos/efectos adversos , Enterocolitis Necrotizante/inducido químicamente , Rifampin/efectos adversos , Tuberculosis Pulmonar/tratamiento farmacológico , Antibióticos Antituberculosos/uso terapéutico , Biopsia , Colonoscopía , Enterocolitis Necrotizante/diagnóstico , Enterocolitis Necrotizante/patología , Femenino , Humanos , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/patología , Persona de Mediana Edad , Rifampin/uso terapéutico , Factores de Riesgo
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