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1.
Phys Rev Lett ; 128(11): 112503, 2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35363014

RESUMO

We have measured the 3d→2p transition x rays of kaonic ^{3}He and ^{4}He atoms using superconducting transition-edge-sensor microcalorimeters with an energy resolution better than 6 eV (FWHM). We determined the energies to be 6224.5±0.4(stat)±0.2(syst) eV and 6463.7±0.3(stat)±0.1(syst) eV, and widths to be 2.5±1.0(stat)±0.4(syst) eV and 1.0±0.6(stat)±0.3(stat) eV, for kaonic ^{3}He and ^{4}He, respectively. These values are nearly 10 times more precise than in previous measurements. Our results exclude the large strong-interaction shifts and widths that are suggested by a coupled-channel approach and agree with calculations based on optical-potential models.

2.
Biosci Biotechnol Biochem ; 65(8): 1796-804, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11577720

RESUMO

A cryoprotective protein, HIC6, was expressed transgenically in tobacco, a cold-sensitive plant, and the localization of the protein within the cell as well as freezing tolerance of the transgenic tobacco was investigated. For constitutive expression of HIC6 in tobacco, its corresponding gene was subcloned into pBI121. Through the transformation with pBI121/hiC6, fifteen transgenic tobacco lines were acquired, out of which twelve lines expressed the HIC6 protein. None of the transgenic tobacco lines, however, showed significant differences in freezing tolerance from the control plants (wild-type and transformed with pBI121) at -1, -3, and -4 degrees C, with the exception that their freezing temperature was -2 degrees C. In order to increase the accumulation level of HIC6, pBE2113 with a stronger promoter was used. Eight lines expressed the protein out of thirteen lines transformed with pBE2113/hiC6. The accumulation levels of the protein were clearly higher in the tobacco plants transformed with pBE2113/hiC6 than in those with pBI121/hiC6. The HIC6 protein seemed to be localized in mitochondria of the transgenic tobacco plants. Freezing-tolerance tests at -1 - -4 degrees C showed that the degree of electrolyte leakage was significantly lower in the plants with pBE2113/hiC6 than in the control plants. A leaf browning observation also showed that high accumulation of HIC6 significantly suppressed injury caused by freezing to the transgenic tobacco at -3 degrees C.


Assuntos
Nicotiana/genética , Nicotiana/fisiologia , Proteínas de Algas/biossíntese , Proteínas de Algas/genética , Southern Blotting , Chlorella/enzimologia , Eletrólitos/metabolismo , Congelamento , Hibridização In Situ , Folhas de Planta/química , Folhas de Planta/metabolismo , Plantas Geneticamente Modificadas , Plasmídeos/genética , Frações Subcelulares/metabolismo
3.
Biosci Biotechnol Biochem ; 64(8): 1656-63, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10993152

RESUMO

The nucleotide sequence of hiC12, isolated as a cDNA clone of hardening-induced Chlorella (hiC) genes, was identified. The clone encodes a late embryogenesis abundant (LEA) protein having six repeats of a 11-mer amino acid motif, although in a slightly imperfect form. To overexpress the hiC61) and hiC12 genes, their coding regions were PCR amplified and subcloned into a pGEX-1lambdaT vector. The HIC6 and HIC12 proteins were expressed as GST fusion proteins in E. coli, then purified. The two HIC proteins were found to be effective in protecting a freeze-labile enzyme, LDH, against freeze-inactivation. On a molar concentration basis, they were about 3.1 x 10(6) times more effective in protecting LDH than sucrose and as effective as BSA. Cryoprotection tests with five kinds of chain-shortened polypeptides, synthesized based on the 11-mer amino acid motif of the HIC6 protein showed that the cryoprotective activity decreased with a decrease in the repeating units of the 11-mer motif. In fact, cryoprotective activities of three kinds of single 11-mer amino acids were very low even at high concentrations. All the results suggested that the sufficiently repeated 11-mer motif is required for the cryoprotective activities of Chlorella LEA proteins.


Assuntos
Chlorella/química , Crioprotetores/metabolismo , Proteínas de Plantas/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Crioprotetores/química , Crioprotetores/isolamento & purificação , Eletroforese em Gel de Poliacrilamida , L-Lactato Desidrogenase/metabolismo , Dados de Sequência Molecular , Proteínas de Plantas/química , Proteínas de Plantas/isolamento & purificação , Conformação Proteica , Alinhamento de Sequência , Relação Estrutura-Atividade
4.
DNA Cell Biol ; 18(4): 275-83, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10235110

RESUMO

Liver-expressed chemokine (LEC) is a CC chemokine that is selectively expressed in the liver. We report here the structures of the human and mouse genes for LEC. The human LEC gene (SCYA16) was isolated from a bacterial artificial chromosome (BAC) clone that also contained CC chemokine genes for MPIF-1/Ckbeta8, HCC-2/Lkn-1/MIP-5/MIP-1delta, and HCC-1. The LEC gene is approximately 5.0 kb in length and has a three-exon and two-intron structure common to most CC chemokine genes. However, the promoter region is devoid of a typical TATA box, and transcription initiates at multiple sites. The gene for CC chemokine HCC-1, which is most similar to LEC, is located approximately 2.2 kb upstream from the 5' end of the LEC gene in a head-to-tail fashion. The mouse DNA fragment that hybridized with the human LEC cDNA was isolated from a BAC clone that also contained the CC chemokine genes for C10, MRP-2/CCF18/MIP-1gamma, and RANTES. Sequence analysis revealed that the isolated gene does not encode a functional chemokine because of deletions, insertions, and base changes. Southern blot analysis revealed that the sequence isolated from the BAC clone was the only one hybridizing with human LEC cDNA in the mouse genome. Therefore, mice may have only an LEC pseudogene.


Assuntos
Quimiocinas CC/genética , Adolescente , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA Complementar , Cobaias , Humanos , Camundongos , Dados de Sequência Molecular , Proteína 2 Associada à Farmacorresistência Múltipla , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Células Tumorais Cultivadas
5.
J Interferon Cytokine Res ; 19(3): 227-34, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10213461

RESUMO

To understand the organization of the human CC chemokine gene cluster on chromosome 17q11.2, we determined the nucleotide sequence of a region 181 kb long containing five CC chemokine genes, MPIF-1 (SCYA23), HCC-2 (SCYA15), HCC-1 (SCYA14), LEC (SCYA16), and RANTES (SCYA5), by the random shot-gun method. The four CC chemokine genes, MPIF-1, HCC-2, HCC-1, and LEC, are clustered within a region 40 kb long, whereas the RANTES gene is located approximately 10 kb apart from the four chemokine gene minicluster. These chemokine genes are arranged in the same orientation, and their sizes are relatively long, 3.1 (HCC-1)-8.8 kb (RANTES) when compared with other CC chemokine genes, such as MIP-1alpha/LD78alpha (SCYA3) (1.9 kb) and MCP-1 (SCYA2) (1.5 kb). In contrast to most other human CC chemokine genes that consist of three exons, the MPIF-1 and HCC-2 genes, separated by 12 kb, have four exons. When the nucleotide sequences of the MPIF-1 and HCC-2 genes are compared, they are well conserved, including introns and flanking sequences, except for the middle region of the long first intron, indicating that they have been generated recently in evolutionary terms by duplication. In addition to the CC chemokine genes, more than 30 exons are identified in the sequenced region by similarity search against expressed sequence tags (ESTs) and also by the gene prediction program GenScan. This indicates that the chemokine cluster sequenced in this study is a gene-rich region in the human genome.


Assuntos
Quimiocinas CC/genética , Cromossomos Humanos Par 17 , Monocinas , Família Multigênica , Sequência de Aminoácidos , Sequência de Bases , Quimiocina CCL5/genética , Clonagem Molecular , Humanos , Proteínas Inflamatórias de Macrófagos , Dados de Sequência Molecular , Filogenia , Homologia de Sequência de Aminoácidos
6.
Genomics ; 55(3): 353-7, 1999 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-10049593

RESUMO

Two loci in the human genome, chromosomes 4q12-q21 and 17q11.2, contain clusters of CXC and CC chemokine subfamily genes, respectively. Since mice appear to contain fewer chemokine genes than humans, numerous gene duplications might have occurred in each locus of the human genome. Here we describe the genomic organization of the human pulmonary and activation-regulated CC chemokine (PARC), also known as DC-CK1 and AMAC-1. Despite high sequence similarity to a CC chemokine macrophage inflammatory protein-1alpha (MIP-1alpha)/LD78alpha, PARC is chemotactic for lymphocytes and not for monocytes and does not share its receptor with MIP-1alpha. Analyses of the BAC clones containing the human PARC gene indicated that the gene is located most closely to MIP-1alpha (HGMW-approved symbol SCYA3) and MIP-1beta (HGMW-approved symbol SCYA4) on chromosome 17q11.2. Dot-plot comparison suggested that the PARC gene had been generated by fusion of two MIP-1alpha-like genes with deletion and selective usage of exons. Base changes accumulated before and after the fusion might have adapted the gene to a new function. Since there are variably duplicated copies of the MIP-1alpha gene called LD78beta (HGMW-approved symbol SCYA3L) in the vicinity of the MIP-1alpha gene, the locus surrounding the MIP-1alpha gene seems to be a "hot spring" that continuously produces new family genes. This evidence provides a new model, duplication and fusion, of the molecular basis for diversity within a gene family.


Assuntos
Quimiocinas CC/genética , Quimiocinas/genética , Proteínas Inflamatórias de Macrófagos/genética , Animais , Sequência de Bases , Quimiocina CCL3 , Quimiocina CCL4 , Evolução Molecular , Humanos , Camundongos , Modelos Biológicos , Modelos Genéticos , Dados de Sequência Molecular , Mapeamento Físico do Cromossomo , Proteínas Recombinantes de Fusão , Homologia de Sequência de Aminoácidos
7.
Biochim Biophys Acta ; 1396(3): 273-7, 1998 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-9545580

RESUMO

We have determined the entire sequence of human cDNA encoding a novel CC chemokine NCC-4 by 5' and 3' RACE methods. Two types of transcripts, 579 bp and 1503 bp long, respectively, are generated through alternative polyadenylation sites. Both species contain an open reading frame encoding 120 amino acids with 19-38% identity to other human CC chemokines. The short and long transcripts are expressed highly selectively in the liver at nearly equivalent levels. There seems to be one copy of the gene per haploid genome. We now designate NCC-4 as LEC from liver-expressed chemokine.


Assuntos
Quimiocinas CC/genética , DNA Complementar/isolamento & purificação , Fígado/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Quimiocinas CC/isolamento & purificação , Clonagem Molecular , Expressão Gênica , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
8.
Genomics ; 34(2): 236-40, 1996 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-8661057

RESUMO

CC chemokines are cytokines that attract and activate leukocytes. The human genes for the CC chemokines are clustered on chromosome 17. To elucidate the genomic organization of the CC chemokine genes, we constructed a YAC contig comprising 34 clones. The contig was shown to contain all 10 CC chemokine genes reported so far, except for one gene whose nucleotide sequence is not available. The contig also contains 4 CC chemokine-like genes, which were deposited in GenBank as ESTs and are here referred to as NCC-1, NCC-2, NCC-3, and NCC-4. Within the contig, the CC chemokine genes were localized in two regions. In addition, the CC chemokine genes were more precisely mapped on chromosome 17q11.2 using a somatic cell hybrid cell DNA panel containing various portions of human chromosome 17. Interestingly, a reciprocal translocation t(Y;17) breakpoint, contained in the hybrid cell line Y1741, lay between the two chromosome 17 chemokine gene regions covered by our YAC contig. From these results, the order and the orientation of CC chemokine genes on chromosome 17 were determined as follows: centromere-neurofibromatosis 1-(MCP-3, MCP-1, NCC-1, I-309)-Y1741 breakpoint-RANTES-(LD78gamma, AT744.2, LD78beta)-(NCC-3, NCC-2, AT744.1, LD78alpha)-NCC-4-retinoic acid receptor alpha- telomere.


Assuntos
Quimiocinas/genética , Cromossomos Humanos Par 17 , Família Multigênica , Animais , Sequência de Bases , Southern Blotting , Quimiocinas/biossíntese , Galinhas , Mapeamento Cromossômico , Cromossomos Artificiais de Levedura , Clonagem Molecular , Primers do DNA , Cobaias , Humanos , Células Híbridas , Camundongos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Proteínas Recombinantes/biossíntese
9.
Psychiatry Clin Neurosci ; 49(2): 131-5, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-8726130

RESUMO

The clinical effects of electroconvulsive therapy (ECT) on the morbidity of paranoid schizophrenic patients were assessed by positron emission tomography (PET) and plasma biochemistry studies before and after ECT. The present study included five patients whose average age was 41.4 years. The average duration of illness was 23.0 years. To avoid any effect of changes in drugs on PET, no changes were made in the medication of any of the five patients during the study period. ECT improved the clinical symptoms in every patient. Regional cerebral blood flow (rCBF) on PET in both temporal lobes and the left cerebellum was higher in paranoid schizophrenia before ECT than in normal subjects, and rCBF after ECT in both frontal lobes, the right temporal lobe and the right putamen was lower than before ECT as mental symptoms improved. These findings suggest high cerebral blood flow volume in paranoid schizophrenia. Plasma biochemistry studies revealed a lower level of 3-methoxy-4-hydroxyphenylglycol (MHPG) after ECT than before ECT, but a higher level of prolactin existed.


Assuntos
Eletroconvulsoterapia , Esquizofrenia Paranoide/fisiopatologia , Esquizofrenia Paranoide/terapia , Adulto , Estudos de Casos e Controles , Circulação Cerebrovascular , Seguimentos , Ácido Homovanílico/sangue , Humanos , Hidrocortisona/sangue , Masculino , Metoxi-Hidroxifenilglicol/sangue , Pessoa de Meia-Idade , Prolactina/sangue , Esquizofrenia Paranoide/sangue , Esquizofrenia Paranoide/diagnóstico por imagem , Fatores de Tempo , Tomografia Computadorizada de Emissão , Resultado do Tratamento
10.
Ann Thorac Surg ; 58(4): 1166-8, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7944773

RESUMO

Open heart operations on patients with hereditary spherocytosis have been reported rarely. Young children who have not yet undergone splenectomy have a high risk of intraoperative hemolysis because of the heart-lung machine and secondary renal failure. We report the case of a 15-month-old child with spherocytosis who underwent an open heart operation without serious complications as a result of careful and appropriate perioperative management.


Assuntos
Insuficiência da Valva Mitral/complicações , Insuficiência da Valva Mitral/cirurgia , Esferocitose Hereditária/complicações , Permeabilidade do Canal Arterial/complicações , Permeabilidade do Canal Arterial/cirurgia , Humanos , Lactente , Masculino
11.
Neuropediatrics ; 25(5): 255-8, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7885535

RESUMO

A case of hemimegalencephaly was studied by means of neuroimaging (CT, MRI and PET) and magnetoencephalography (MEG). Hemimegalencephaly (HM) is a neuronal migration disorder. This is the first report of evaluation of HM with the use of PET and MEG from not only the morphological but also the functional point of view. PET with 11C-glucose showed a low radioactive concentration in the affected hemisphere, which suggested a metabolic deficit. MEG proved the epileptic foci existed mainly in the affected hemisphere, especially around a heterotopia and the pachygyric cortex, which was disclosed on MRI.


Assuntos
Encéfalo/anormalidades , Encéfalo/metabolismo , Magnetoencefalografia , Encéfalo/fisiopatologia , Feminino , Glucose/metabolismo , Humanos , Lactente , Imageamento por Ressonância Magnética , Tomografia Computadorizada de Emissão , Tomografia Computadorizada por Raios X
12.
Nihon Kyobu Geka Gakkai Zasshi ; 42(7): 1003-6, 1994 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-8089563

RESUMO

Surgical treatment for a hypoplastic aortic arch associated with coarctation or interruption of the aorta is controversial. We evaluate the changes of diameter of proximal transverse aortic arch after surgery in 28 patients. Proximal transverse aortic arch in all patients was preoperatively 3.5 +/- 0.9 mm (2.5 to 7 mm), and 54 +/- 12% (36 to 84%) to the normal aortic valve dimension (n-AVD: 16.6 X BSA0.6). While postoperative proximal transverse aortic arch was 6.5 +/- 1.8 mm, and 76 +/- 12% to the n-AVD, and significantly grew more than the preoperative arch dimension (p = 0.0001). In 18 patients having two times cardiac catheterization postoperatively, proximal transverse aortic arch was 6.5 +/- 1.6 mm, and 75 +/- 13% to n-AVD on the 1st postoperative examination. On the 2nd examination, the arch was 9.9 +/- 1.9 mm, and 88 +/- 12% to n-AVD, and significantly grew with increasing years (p < or = 0.0003). We concluded that the proximal transverse aortic arch, which was more than 36% to n-AVD in diameter, if not dilated surgically, grew with increasing years after aortic arch repair.


Assuntos
Aorta Torácica/anormalidades , Aorta Torácica/crescimento & desenvolvimento , Coartação Aórtica/cirurgia , Aorta Torácica/cirurgia , Coartação Aórtica/patologia , Valva Aórtica/patologia , Pré-Escolar , Humanos , Lactente
13.
Nihon Kyobu Geka Gakkai Zasshi ; 42(6): 839-44, 1994 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-8057014

RESUMO

Eight patients with a mean age of 13.0 years underwent reoperation for obstructed extracardiac dacron conduit with xenograft valve at a mean of 7 years after Rastelli operation. In two patients, infective endocarditis of the stenotic conduit was the main indication for the reoperation. Diagnoses included 3 tetralogy of Fallot with pulmonary atresia, 3 d-TGA (III), 1 truncus arteriosus, and 1 corrected TGA. The conduit was completely excised leaving the posterior half of the autogenous external peel of conduit as the new outflow bed and a monocusped patch was then placed. Operations were mostly carried out allowing the heart to continue to beat. One patient with c-TGA who underwent concomitant replacement of aortic and left A-V values died in the hospital 4 months postoperatively. In other 7 patients, systolic pressure gradient across the right ventricular outflow decreased from a mean of 80.3 mmHg to 16.0 mmHg. Postoperative pulmonary regurgitation by UCG were trivial in 3 and grade III in 3 patients. One patient required re-reoperation late postoperatively for re-stenosis due to contracture of Golaski outflow patch. Three patients did not require any homologous blood during either the operation or the rest of the hospital stay. The results suggests that this method is a simple and effective option for reoperation of obstructed extracardiac dacron conduits late after Rastelli operation.


Assuntos
Bioprótese , Prótese Vascular , Próteses Valvulares Cardíacas , Ventrículos do Coração/cirurgia , Artéria Pulmonar/cirurgia , Adolescente , Criança , Pré-Escolar , Constrição Patológica/cirurgia , Cardiopatias Congênitas/cirurgia , Humanos , Falha de Prótese , Reoperação/métodos
14.
Nihon Kyobu Geka Gakkai Zasshi ; 42(2): 233-6, 1994 Feb.
Artigo em Japonês | MEDLINE | ID: mdl-8138692

RESUMO

Left ventricular outflow tract (LVOT) dimension was measured in seven patients with coarctation (CoA) or interruption (IAA) of the aorta before and after aortic arch repair and pulmonary artery banding. The age of patients ranged 3 to 69 (mean 16) days, the weight 3.0 to 3.9 (mean 3.4) kg. Associated cardiac anomalies were VSD in 6, MA and DORV in 1. In five patients compared by ultrasound, preoperative LVOT dimension ranged from 3.5 to 5.0 (mean 4.4) mm with the ratio to the normal aortic valve dimension (n-AVD; 16.6 x BSA0.6) from 54 to 82 (mean 69)%. Postoperative dimension increased 5.0 to 7.4 (mean 5.7) mm and the ratio to the n-AVD increased 65 to 89 (mean 80)%. In three patients compared by LV graphy, preoperative LVOT dimension ranged from 4.0 to 4.5 (4.2) mm and the ratio ranged from 61 to 72 (68)%. Postoperative dimension increased from 4.5 to 6.7 (5.3) mm, and 74 to 80 (78)% to n-AVD after operation. Postoperative pressure gradients between LV and ascending aorta in each patient were 1 to 9 (mean 6) mmHg. In any patients, LVOT obstruction did not advance after aortic arch repair and pulmonary artery banding.


Assuntos
Aorta Torácica/cirurgia , Aorta/anormalidades , Coartação Aórtica/cirurgia , Estenose da Valva Aórtica/cirurgia , Artéria Pulmonar/cirurgia , Coartação Aórtica/complicações , Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/complicações , Ecocardiografia , Ventrículos do Coração/diagnóstico por imagem , Humanos , Lactente , Recém-Nascido
15.
J Nucl Med ; 34(11): 1886-91, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8229229

RESUMO

Carbon-11-methionine PET scans were obtained from 24 patients with non-small-cell lung carcinoma for whom surgical treatment was considered. The tumor mass was visualized with clear delineation. After PET scanning, the tumor was removed by lobectomy or pulmonectomy. The tumor tissue was first processed to yield tumor cell suspensions and then subjected to DNA flow cytometry. Comparison between 11C uptake rate and flow-cytometric data gave the following results: 11C uptake rate in the tumor correlated well with the cellular DNA content (DNA index) of tumor cells at the resting state of cell division (G0 + G1-phase) (r = 0.67). The correlation between 11C uptake rate and S-phase cell percentage was markedly high (r = 0.76), and the correlation between 11C uptake rate and S+G2/M-phase cell percentage was extremely high (r = 0.86). It was concluded that the tumor uptake rate of 11C-methionine was representative of tumor growth rate in this tumor type.


Assuntos
Radioisótopos de Carbono , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Citometria de Fluxo , Neoplasias Pulmonares/diagnóstico por imagem , Metionina , Tomografia Computadorizada de Emissão , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Ciclo Celular , Divisão Celular , DNA de Neoplasias/análise , Feminino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Ploidias
17.
Brain Dev ; 14 Suppl: S69-74, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1626637

RESUMO

Positron emission tomography (PET) was performed on six patients with the Rett syndrome and the results were compared with the concurrent clinical status of the patients. The cerebral metabolic rate of oxygen (CMRO2) was low in five patients, and oxygen extraction fraction (OEF) was low in four patients; both had a tendency to decline with advancing age. Although the cause is unknown, it is suggested that impaired oxidative metabolism exists in the Rett syndrome. An analysis of the distribution among brain regions showed that the ratios of values for the frontal cortex to those for the temporal cortex for both the cerebral blood flow (CBF) and CMRO2 were lower than those for the controls, which may indicate the loss of hyperfrontality in the Rett syndrome. Distribution of brain metabolism may be immature in the Rett syndrome.


Assuntos
Circulação Cerebrovascular/fisiologia , Oxigênio/metabolismo , Síndrome de Rett/diagnóstico por imagem , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Síndrome de Rett/metabolismo , Síndrome de Rett/fisiopatologia , Tomografia Computadorizada de Emissão
18.
Chromosoma ; 101(7): 413-9, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1618024

RESUMO

Extrachromosomal nucleoli were isolated from log phase cells of Tetrahymena pyriformis (amicronucleate strain) in a highly purified state. Nucleoli located at the periphery of the macronucleus were detached from the nucleoplasmic mass of isolated macronuclei with agitation and separated from macronuclei by filtration through a Nuclepore membrane filter (pore size 5 microm). The filtrate constitutes the crude nucleolar preparation, as judged by electron microscopy and DNA analysis. Further purification of the nucleoli was performed by isopycnic centrifugation of the filtrate in a Metrizamide density gradient. After this step, the purity of the nucleoli, as defined by rDNA content and measured by analytical CsCl centrifugation, was almost 100%. Electron microscopy of the purified nucleoli revealed structures that resemble those of an in situ nucleoli. Undegraded 35S pre-rRNA, together with 26S and 17S rRNA, could be isolated from purified nucleoli. In vitro RNA synthetic activity was associated with isolated nucleoli. This activity is insensitive to low and high concentrations of alpha-amanitin, indicating that the form I RNA polymerase is functioning.


Assuntos
Nucléolo Celular/fisiologia , Tetrahymena pyriformis/fisiologia , Animais , Fracionamento Celular/métodos , Nucléolo Celular/ultraestrutura , Centrifugação com Gradiente de Concentração , DNA de Protozoário/isolamento & purificação , Precursores de RNA/isolamento & purificação , RNA de Protozoário/isolamento & purificação , RNA de Protozoário/metabolismo , RNA Ribossômico/isolamento & purificação , Tetrahymena pyriformis/metabolismo , Tetrahymena pyriformis/ultraestrutura
19.
Kokyu To Junkan ; 40(3): 283-7, 1992 Mar.
Artigo em Japonês | MEDLINE | ID: mdl-1579751

RESUMO

We have measured regional alveolar volume and regional ventilation of emphysematous lesions and periemphysematous lesions with positron emission tomography and N-13 gas in 10 patients. The purpose of the study was to investigate how emphysematous lesion develops. The subjects were all male (except one) who put on a mask in supine position, and were connected with a spirometer. We gave N-13 gas in this closed circuit and had the gas rebreathed by the subjects. After activity reached equilibrium in closed circuit, an equilibrium scan was made. We took "activity gas" from the closed circuit and measured activity by well counter during equilibrium to get quantitative alveolar volume. The activity in closed circuit during equilibrium showed activity in the thoracic unit. After equilibrium, we used air to wash out radioactive gas from the circuit. During washout we took 3 sequential images. The decreased rate of activity in the region of interest from these 3 sequential washout images was expressed in a monoexponential curve. The index of monoexponential denotes V/V. Alveolar volume in emphysematous lesions was 34.8 +/- 19.5 ml/100ml thoracic volume, and V/V in these lesions was 0.27 +/- 0.21/min. On the other hand alveolar volume in periemphysematous lesions was 76.5 +/- 13.1 ml/100ml thoracic volume, and V/V was 0.38 +/- 0.22/min. Thus alveolar volume in periemphysematous lesions was relatively high. These results indicate that the effect of emphysematous lesions as compared with periemphysematous lesions was not direct compression of alveolar space. The direct effect was compression to the bronchiole of peripheral lesions, and check valve mechanism occurred in the bronchiole causing peripheral lesions resulting in the destruction of the alveolar wall.


Assuntos
Alvéolos Pulmonares/fisiopatologia , Enfisema Pulmonar/fisiopatologia , Adulto , Idoso , Cistos/fisiopatologia , Feminino , Humanos , Medidas de Volume Pulmonar , Masculino , Pessoa de Meia-Idade , Enfisema Pulmonar/diagnóstico por imagem , Tomografia Computadorizada de Emissão
20.
Cytotechnology ; 10(2): 175-81, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1369213

RESUMO

Transforming growth factor beta 1 (1 ng/ml) caused death of serum-free mouse embryo cells cultured in a medium consisting of a 1:1 mixture of Dulbecco's Modified Eagle's medium and Ham's F12 medium supplemented with fibronectin, insulin, transferrin, epidermal growth factor, and high density lipoprotein. Cell death occurred in the presence of polyunsaturated fatty acids including linoleic acid in the absence of selenium. The death could be reversed by adding alpha-tocopherol to the culture indicating a mechanism involving fatty acid peroxidation. Butylated hydroxytoluene was a poor suppressor of cell death in contrast to alpha-tocopherol. High density lipoprotein and fatty acid-free albumin also suppressed cell death at the level of 20 micrograms/ml and 1 mg/ml, respectively. Transforming growth factor beta 1 also caused a low rate of cell growth after heat treatment of the cells at 45 degrees C.


Assuntos
Meios de Cultura Livres de Soro , Embrião de Mamíferos/citologia , Fator de Crescimento Transformador beta/toxicidade , Albuminas/farmacologia , Animais , Hidroxitolueno Butilado/farmacologia , Morte Celular/efeitos dos fármacos , Meios de Cultura Livres de Soro/química , Ácidos Graxos/farmacologia , Temperatura Alta , Ácido Linoleico , Ácidos Linoleicos/farmacologia , Lipoproteínas HDL/farmacologia , Camundongos , Camundongos Endogâmicos BALB C/embriologia , Selênio/farmacologia , Fator de Crescimento Transformador beta/farmacologia , Vitamina E/farmacologia
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