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1.
Artigo em Chinês | MEDLINE | ID: mdl-36725290

RESUMO

Objective: Differential flora and differential metabolites shared by the intestinal and respiratory tracts of rats were screened to analyze the possible role of changes in intestinal flora and metabolites in the progression of pneumoconiosis in rats. Methods: In April 2020, 18 SD rats were randomly divided into three groups (control group, coal mine dust group and silica group, 6 in each group) , rats in the coal mine dust group and silica group were perfused with 1 ml of 50 mg/ml coal mine well dust suspension and silica suspension by nontracheal exposure, respectively. While rats in the control group were perfused with an equal dose of sterilized normal saline. Twenty four weeks after dust staining, rat feces, throat swabs, and lung lavages were collected. 16SrDNA gene sequencing and UHPLC-QTOF-MS untargeted metabolomics were used to analyze the flora and metabolites in feces, throat swabs and lung lavage fluid of rats in each group, to screen for shared differential flora and shared differential metabolites in intestinal and respiratory tract, and the correlation analysis between the differential flora and metabolites was performed using Spearman's statistics. Results: Compared with the control group, a total of 9 species shared differential flora between intestinal and respiratory tract were screened at phylum level, and a total of 9 species shared differential genus between intestinal and respiratory tract were screened at genus level in the coal mine dust group, mainly Firmicutes, Actinobacteria, Streptococcus, Lactobacillus, etc. Compared with the control group, a total of 9 shared differential flora were screened at the phylum level, and a total of 5 shared differential genus were screened at the genus level in the silica group, mainly Proteobacteria, Actinobacteria, Allobactera, Mucilaginibacter, etc. Compared with the control group, a total of 7 shared differential metabolites were screened for up-regulation of Stigmatellin, Linalool oxide and Isoleucine-leucine in both intestinal and respiratory tract in the coal mine dust group. Compared with the control group , a total of 19 shared differential metabolites werescreened in the silica group, of which Diethanolamine, 1-Aminocyclopropanecarboxylic acid, Isoleucine-leucine, Sphingosine, Palmitic acid, D-sphinganine, 1, 2-dioleoyl-sn-glycero-3-phosphatidylcholine, and 1-Stearoyl-2-oleoyl-sn-glycerol 3-phosphocholine were up-regulated in both the intestinal and respiratory tract. Conclusion: There is a translocation of intestinal and respiratory flora in pneumoconiosis rats, and rats have an imbalance of lipid metabolism during the progression of pneumoconiosis.


Assuntos
Minas de Carvão , Pneumoconiose , Ratos , Animais , Isoleucina , Leucina , Ratos Sprague-Dawley , Poeira/análise , Dióxido de Silício , Carvão Mineral
2.
Artigo em Chinês | MEDLINE | ID: mdl-33535334

RESUMO

Objective: To explore the relationship between input and output of occupational health funds, and to provide basis for relevant departments to make decisions. Methods: In September 2018, a state-owned iron ore in Hebei Province (mining history of more than 10 years, which can represent the general type of iron ore) was selected as the research object. Through the investigation and collection of enterprise general situation, occupational health input, loss and output related indicators, the iron mine occupational health expenditure input-output table and model were established, and the digital relationship between the investment and output was solved by MATLAB software. Results: The labor consumption in the departments of underground mining, open pit mining, crushing and rock discharging, transportation, tailings and mineral processing (taking labor wages as reference) were 756.46, 1.281.78, 987.61, 1 570.71, 50.956 and 18.9116 million yuan/year respectively. The output value of each sector is 11 207.19, 18 989.95, 15 176.40, 25 294.00, 7.704.94 and 280.1797 million yuan/year respectively. The ratio of health input to total output was 0.004 5, and the ratio of occupational health input to output was 1/0.046. Conclusion: The input-output table model of occupational health in iron mine can reflect the relationship between input and output of occupational health funds. The input situation of the coal mine is poor, and the input does not bring obvious occupational health benefits.


Assuntos
Saúde Ocupacional , Ferro , Mineração
3.
Infection ; 43(1): 117-20, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25156885

RESUMO

Little is known about the virulence and clinical impact on humans from infection with Anaeroglobus geminates, an anaerobic gram-negative coccus belonging to the family Veillonellaceae. We report the first case of an Anaeroglobus geminates invasive infection in humans characterized by pneumonia complicated with empyema. The pathogen was initially identified as Veillonella spp. by an automatic identification system (Becton-Dickinson and Company, Franklin Lakes, NJ, USA) and definitively identified following 16S ribosomal RNA gene sequence analysis. The patient was cured by surgical decortication and antimicrobial therapy. In this case, the combination of effective antibiotics, surgical intervention, and adequate drainage successfully cured the patient.


Assuntos
Empiema , Infecções por Bactérias Gram-Negativas , Pneumonia Bacteriana , Veillonellaceae , Idoso , DNA Bacteriano/análise , DNA Bacteriano/genética , Feminino , Humanos , Radiografia Torácica , Veillonellaceae/classificação , Veillonellaceae/genética
4.
Genetika ; 50(4): 443-51, 2014 Apr.
Artigo em Russo | MEDLINE | ID: mdl-25715446

RESUMO

Genomic in situ hybridization (GISH) was used for a chromosomal composition study of the later generations of interspecific hybrids between A. cepa L. and A. fistulosum L., which are relatively resistant to downy mildew (peronosporosis). GISH revealed that F2 hybrids, which did not produce seeds, were triploids (2n = 3x = 24) with 24 chromosomes and possessed in their compliments 16 chromosomes of A. fistulosum L. and eight chromosomes of A. cepa L. or eight chromosomes of A. fistulosum L. and 16 chromosomes of A. cepa L. The advanced F5 hybrid, which produced few seeds, was amphidiploid with 32 chromosomes. BC1F5 hybrid was triploid with eight chromosomes of A. fistulosum L. and 16 chromosomes of A. cepa L., which did not produce seeds. BC2 (BC1F5) plant was amphidiploid that possessed 4 recombinant chromosomes and produced few seeds. GISH results point to 2n-gametes formation in macro- and microsporogenesis of the hybrids. The mechanism of 2n-gametes formation and the possibility of apomixes events in the backcrossing progeny are discussed.


Assuntos
Cromossomos de Plantas/genética , Resistência à Doença/genética , Hibridização Genética , Cebolas/citologia , Apomixia , Hibridização in Situ Fluorescente , Cebolas/genética
5.
Eur Rev Med Pharmacol Sci ; 27(8): 3351-3362, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37140285

RESUMO

OBJECTIVE: Animal studies and clinical trials demonstrated the effectiveness of a combination of transplanted bone marrow stromal cells (BMSC) and electroacupuncture (EA) treatment in improving neurological deficits. However, the ability of the BMSC-EA treatment to enhance brain repair processes or the neuronal plasticity of BMSC in ischemic stroke model is unclear. The purpose of this study was to investigate the neuroprotective effects and neuronal plasticity of BMSC transplantation combined with EA in ischemic stroke. MATERIALS AND METHODS: A male Sprague-Dawley (SD) rat middle cerebral artery occlusion (MCAO) model was used. Intracerebral transplantation of BMSC, transfected with lentiviral vectors expressing green fluorescent protein (GFP), was performed using a stereotactic apparatus after modeling. MCAO rats were treated with BMSC injection alone or in combination with EA. After the treatment, proliferation and migration of BMSC were observed in different groups by fluorescence microscopy. Quantitative real-time PCR (qRT-PCR), Western blotting, and immunohistochemistry were performed to examine changes in the levels of neuron-specific enolase (NSE) and nestin in the injured striatum. RESULTS: Epifluorescence microscopy revealed that most BMSC in the cerebrum were lysed; few transplanted BMSC survived, and some living cells migrated to areas around the lesion site. NSE was overexpressed in the striatum of MCAO rats, illustrating the neurological deficits caused by cerebral ischemia-reperfusion. The combination of BMSC transplantation and EA attenuated the expression of NSE, indicating nerve injury repair. Although the qRT-PCR results showed that BMSC-EA treatment elevated nestin RNA expression, less robust responses were observed in other tests. CONCLUSIONS: Our results show that the combination treatment significantly improved restoration of neurological deficits in the animal stroke model. However, further studies are required to see if EA could promote the rapid differentiation of BMSC into neural stem cells in the short term.


Assuntos
Isquemia Encefálica , Eletroacupuntura , AVC Isquêmico , Células-Tronco Mesenquimais , Acidente Vascular Cerebral , Ratos , Masculino , Animais , Ratos Sprague-Dawley , AVC Isquêmico/metabolismo , Nestina/metabolismo , Isquemia Encefálica/metabolismo , Acidente Vascular Cerebral/metabolismo , Células-Tronco Mesenquimais/metabolismo , Infarto da Artéria Cerebral Média/terapia , Infarto da Artéria Cerebral Média/metabolismo , Células da Medula Óssea , Células Estromais/metabolismo , Transplante de Medula Óssea/métodos
6.
Br J Cancer ; 107(12): 1917-24, 2012 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-23169286

RESUMO

BACKGROUND: Round 1 data of human papillomavirus (HPV) FOCAL, a three-arm, randomised trial, which aims to establish the efficacy of HPV DNA testing as a primary screen for cervical cancer, are presented. METHODS: The three arms are: Control arm - liquid based cytology with atypical squamous cells of unknown significance (ASC-US) triage with hrHPV testing; Intervention Arm - hrHPV at entry with liquid-based cytology (LBC) triage of hrHPV positives, with exit screen at 4 years; Safety check arm - hrHPV at entry with LBC triage of hrHPV positives with exit screen at 2 years. RESULTS: A total of 6154 women were randomised to the control arm and 12 494 to the HPV arms (intervention and safety check). In the HPV arm, the baseline cervical intraepithelial neoplasia (CIN)2+ and CIN3+ rate was 9.2/1000 (95%CI; 7.4, 10.9) and 4.8/1000 (95%CI; 3.6, 6.1), which increased to 16.1/1000 (95%CI 13.2, 18.9) for CIN2+ and to 8.0/1000 (95%CI; 5.9, 10.0) for CIN3+ after subsequent screening of HPV-DNA-positive/cytology-negative women. Detection rate in the control arm remained unchanged after subsequent screening of ASC-US-positive/hrHPV DNA-negative women at 11.0/1000 for CIN2+ and 5.0/1000 for CIN3+. CONCLUSION: After subsequent screening of women who were either hrHPV positive/cytology negative or ASC-US positive/HPV negative, women randomised to the HPV arms had increased CIN2+ detection compared with women randomised to the cytology arm.


Assuntos
Alphapapillomavirus/isolamento & purificação , Técnicas Citológicas/métodos , Detecção Precoce de Câncer/métodos , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/virologia , Adulto , Algoritmos , Alphapapillomavirus/genética , Canadá/epidemiologia , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/virologia , Colposcopia , DNA Viral/isolamento & purificação , Feminino , Humanos , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Infecções por Papillomavirus/epidemiologia , Parceiros Sexuais , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/prevenção & controle , Esfregaço Vaginal , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/virologia
7.
Rapid Commun Mass Spectrom ; 25(20): 3123-30, 2011 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-21953968

RESUMO

The possible interaction of environmental contaminants with the endocrine system has been an environmental concern since the early 1990s. To examine these interactions test guidelines have been introduced by regulatory agencies to screen for possible endocrine active compounds. One of these guidelines is the EPA's OPPTS 890.1550 [Steroidogenesis (Human Cell Line-H295R)]. This guideline requires the quantification of two major biomarkers (testosterone and estradiol) in various biological test systems. Traditional quantitation methodologies such as Radioimmunoassay (RIA) and Enzyme-linked Immunosorbent Assay (ELISA) have been used to quantify low levels of steroids. However, those methodologies have drawbacks such as the radioactive safety, antibody availability, separate assay for each biomarker, and lack of selectivity. In the current study, a rapid and sensitive liquid chromatography/positive atmospheric pressure photoionization tandem mass spectrometry method (LC/APPI-MS/MS) has been developed and validated for the simultaneous quantitation of testosterone and estradiol in the H295R cell line. Briefly, the media from cultured cells was extracted with dichloromethane (CH(2)Cl(2)) containing internal standards of both testosterone-d(3) and estradiol-(13)C(3); then, the extracted organic layer was concentrated down to dryness. The final residue was derivatized with dansyl chloride solution, and directly analyzed by LC/APPI-MS/MS. The calibration curves, with concentration ranging from 10 to 2500 pg/mL, were linear with coefficient >0.99. The lower limits of quantitation for both testosterone and estradiol were 10 pg/mL. This method was successfully validated to support requirements of the current EPA Steroidogenesis guideline. This type of method may also provide value for rapid and precise measurements of these two hormones in other in vitro or in vivo test systems.


Assuntos
Cromatografia Líquida/métodos , Estradiol/análise , Espectrometria de Massas em Tandem/métodos , Testosterona/análise , Ácido Acético/química , Acetonitrilas/química , Linhagem Celular , Humanos , Modelos Lineares , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
Science ; 238(4826): 498-504, 1987 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-3310237

RESUMO

The DNA double helix is not a regular, featureless barberpole molecule. Different base sequences have their own special signature, in the way that they influence groove width, helical twist, bending, and mechanical rigidity or resistance to bending. These special features probably help other molecules such as repressors to read and recognize one base sequence in preference to another. Single crystal x-ray structure analysis is beginning to show us the various structures possible in the B-DNA family. The DNA decamer C-C-A-A-G-A-T-T-G-G appears to be a better model for mixed-sequence B-DNA than was the earlier C-G-C-G-A-A-T-T-C-G-C-G, which is more akin to regions of poly(dA).poly(dT). The G.A mismatch base pairs at the center of the decamer are in the anti-anti conformation about their bonds from base to sugar, in agreement with nuclear magnetic resonance evidence on this and other sequences, and in contrast to the anti-syn geometry reported for G.A pairs in C-G-C-G-A-A-T-T-A-G-C-G. The ordered spine of hydration seen earlier in the narrow-grooved dodecamer has its counterpart, in this wide-grooved decamer, in two strings of water molecules lining the walls of the minor groove, bridging from purine N3 or pyrimidine O2, to the following sugar O4'. The same strings of hydration are present in the phosphorothioate analog of G-C-G-C-G-C. Unlike the spine, which is broken up by the intrusion of amine groups at guanines, these water strings are found in general, mixed-sequence DNA because they can pass by unimpeded to either side of a guanine N2 amine. The spine and strings are perceived as two extremes of a general pattern of hydration of the minor groove, which probably is the dominant factor in making B-DNA the preferred form at high hydration.


Assuntos
DNA , Conformação de Ácido Nucleico , Oligodesoxirribonucleotídeos , Composição de Bases , Sequência de Bases , Cristalização , Fosfatos , Água
9.
Cancer Genet Cytogenet ; 181(1): 40-5, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18262052

RESUMO

The cell line ARH77 is derived from a patient with plasma cell leukemia and has a complex and continually evolving karyotype. It is frequently used in biological studies of myeloma and plasma cell leukemia, so accurate characterization of the genome is valuable. Here we present a detailed cytogenetic investigation using G-banding and multicolor fluorescence in situ hybridization (M-FISH) in association with assessment of copy number alterations (CNAs) throughout the genome using array-based comparative genomic hybridization (aCGH). In addition to providing an accurate description of the karyotype, this complementary approach highlighted the relative merits of the individual techniques. Conventional cytogenetics and M-FISH indicated the location and types of the major chromosomal changes, whether balanced or unbalanced, and at the same time demonstrated the level of karyotypic evolution between cells. The aCGH profiles reflected the unbalanced chromosomal abnormalities detected by cytogenetics, providing refinement of their genomic breakpoint locations as well as the identification of novel genomic changes. Three aCGH platforms, comprising bacterial artificial chromosome (BAC) or oligonucleotide templates, were available for evaluation. Sixteen CNAs were consistently detected by all three platforms. Novel submicroscopic CNAs ( approximately 0.4 Mb) were detected by the highest resolution platform only, whereas the clones from the BAC arrays provided locus-specific FISH probes for confirmation of CNA.


Assuntos
Leucemia Plasmocitária/genética , Linhagem Celular Tumoral , Bandeamento Cromossômico , Mapeamento Cromossômico , Perfilação da Expressão Gênica , Genoma Humano , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Hibridização de Ácido Nucleico , Prognóstico
10.
J Clin Invest ; 86(4): 1124-36, 1990 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2212003

RESUMO

Accumulating evidence implicates a central role for synovial T cells in the pathogenesis of rheumatoid arthritis, but the activation pathways that drive proliferation and effector function of these cells are not known. We have recently generated a novel monoclonal antibody against a rheumatoid synovial T cell line that recognizes an antigen termed UM4D4 (CDw60). This antigen is expressed on a minority of peripheral blood T cells, and represents the surface component of a distinct pathway of human T cell activation. The current studies were performed to examine the expression and function of UM4D4 on T cells obtained from synovial fluid and synovial membranes of patients with rheumatoid arthritis and other forms of inflammatory joint disease. The UM4D4 antigen is expressed at high surface density on about three-fourths of synovial fluid T cells and on a small subset of synovial fluid natural killer cells; in synovial tissue it is present on more than 90% of T cells in lymphoid aggregates, and on approximately 50% of T cells in stromal infiltrates In addition, UM4D4 is expressed in synovial tissue on a previously undescribed population of HLA-DR/DP-negative non-T cells with a dendritic morphology. Anti-UM4D4 was co-mitogenic for both RA and non-RA synovial fluid mononuclear cells, and induced IL-2 receptor expression. The UM4D4/CDw60 antigen may represent a functional activation pathway for synovial compartment T cells, which could play an important role in the pathogenesis of inflammatory arthritis.


Assuntos
Antígenos CD/análise , Antígenos de Diferenciação de Linfócitos T/análise , Artrite Reumatoide/imunologia , Ativação Linfocitária , Líquido Sinovial/imunologia , Linfócitos T/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos de Diferenciação de Linfócitos T/fisiologia , Antígenos de Superfície/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Receptores de Interleucina-2/análise , Acetato de Tetradecanoilforbol/farmacologia
11.
J Am Acad Child Adolesc Psychiatry ; 45(8): 1000-1006, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16865043

RESUMO

OBJECTIVE: The authors examined the ethical and practical management issues resulting from the detection of incidental abnormal findings on magnetic resonance imaging (MRI) research studies in healthy pediatric volunteers. METHOD: A retrospective examination of the findings from 60 clinical reports of research MRI scans from a cohort of healthy pediatric volunteers (ages 10-21) was conducted. RESULTS: A neuroradiologist noted incidental abnormalities in 8 (13%) of 60 subjects. Of these eight children, three (5%) adolescents were found to have abnormalities (possible tumor, possible vascular malformation, and unidentified bright object in white matter, respectively) that were judged to require further diagnostic workup. In the first two cases, follow-up MRI ruled out the possibility of a tumor or vascular malformation. In the third case, a follow-up MRI 24 months later found that the white matter abnormality remained stable and was thus deemed to be of no clinical significance. CONCLUSIONS: In healthy children who are participating in research MRI protocols, it is ethically difficult to determine whether films should be read clinically. Based on this retrospective analysis, there would have been no risk(s) associated with not reading the films. In contrast, considerable anxiety was generated as a consequence of having the scans clinically read by a neuroradiologist because of the reporting of incidental abnormalities that later turned out to be false positives. Also, the detection of no abnormality on a research-quality scan could imply erroneously to some subjects that no abnormality was present, which may have been falsely reassuring.


Assuntos
Ansiedade/etiologia , Conscientização , Revelação/ética , Revelação/estatística & dados numéricos , Imageamento por Ressonância Magnética/ética , Neoplasias/epidemiologia , Neoplasias/psicologia , Adolescente , Adulto , Criança , Estudos de Coortes , Humanos , Incidência , Estudos Retrospectivos
12.
Biochim Biophys Acta ; 970(3): 262-9, 1988 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-3401510

RESUMO

The 31P nuclear magnetic resonance spectrum of cultured human Y-79 retinoblastoma cells was obtained at 121 MHz on intact cells trapped in agarose threads. The spectrum was dominated by monoester peaks, which varied in relative concentration from preparation to preparation. Resonances from phosphocreatine, phosphodiesters and diphosphodiesters also exhibited variability relative to ATP. The main monoester was identified as phosphorylcholine by 31P-NMR of perchloric acid extracts. It was determined that the changes in monoester concentration correlated with feeding pattern. Phosphorus spectra of cells 1, 2 and 3 days post feeding showed a 40% decrease in the relative concentration of phosphorylcholine concentration over the 3 day period. Phosphocreatine, phosphodiesters and diphosphodiesters increased relative to ATP during the same period. Growth curve experiments and oxygen consumption measurements indicated that the decrease in phosphorylcholine correlated with a decrease in cellular growth and oxygen consumption. We conclude that monoester concentration may be a useful indicator of nutritional status in these cells and possibly in intact tumors.


Assuntos
Retinoblastoma/metabolismo , Linhagem Celular , Humanos , Espectroscopia de Ressonância Magnética , Fósforo
13.
Biochim Biophys Acta ; 629(1): 178-83, 1980 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-7370305

RESUMO

A simple and effective method of the methylation on the 2'-O position of adenosine is described. Adenosine is treated with CH3I in an anhydrous alkaline medium at 0 degrees C for 4 h. The major products of this reaction are monomethylated adenosine at either the 2'-O or 3'-O position (total of 64%) and the side products are dimethylated adenosine ((2', 3'-O-dimethyladenosine, 21%, and N6-2'-O-dimethyladenosine, 11%). The ratio of 2'-O- and 3'-O-methyladenosine has been found to be 8 to 1. Therefore, this reaction preferentially favors the synthesis of 2'-O-methyladenosine. The monomethylated adenosine is isolated from reaction mixture by a silica gel column chromatography. Then the pure 2'-O-methyladenosine can be separated by crystallization in ethanol from the mixture of 2'=O and 3'-O-methylated isomers. The overall yield of 2'-O-methyladenosine is 42%.


Assuntos
Adenosina , Adenosina/análogos & derivados , Iodetos , Adenosina/síntese química , Fenômenos Químicos , Química , Cromatografia em Camada Fina/métodos , Cristalização , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Metilação , Espectrofotometria Ultravioleta
14.
Biochimie ; 67(3-4): 277-92, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3929843

RESUMO

This survey focuses on recent developments in the far ultraviolet photochemistry of nucleic acids and related model compounds. The photoproducts discussed are the cyclobutidipyrimidines, the pyrimidine-pyrimidone adducts, the purine-pyrimidine adducts and the addition products of amino acids to pyrimidine bases. The specific aspects of the high-intensity laser photochemistry of nucleic acid components are also briefly reviewed.


Assuntos
DNA/efeitos da radiação , Raios Ultravioleta , Aminoácidos , Sequência de Bases , Fenômenos Químicos , Química , Ciclobutanos , Citosina , DNA/análise , Reparo do DNA , Desoxirribodipirimidina Fotoliase/metabolismo , Lasers , Lisina , Substâncias Macromoleculares , Espectroscopia de Ressonância Magnética , Conformação de Ácido Nucleico , Oligodesoxirribonucleotídeos , Fotoquímica , Fotólise , Purinas , Dímeros de Pirimidina/análise , Pirimidinas , Pirimidinonas , Análise Espectral , Timina , Triptofano , Difração de Raios X
15.
Invest Ophthalmol Vis Sci ; 28(1): 70-5, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3804654

RESUMO

Cultured human retinal pigmented epithelial cells were studied using phosphorus-31 nuclear magnetic resonance spectroscopy (P-31 NMR). Retinal pigmented epithelial cells from normal human donors were isolated and expanded using roller-bottle culture. The P-31 NMR spectrum of the intact living cells was obtained at 121 MHz by casting the cells in agarose threads and perfusing the threads with culture medium. The cells remained viable at 37 degrees C in the NMR magnet for at least 24 hr, as determined by the stability of the phosphorus spectrum and by trypan blue dye exclusion at the end of the experiments. The intact cell spectrum showed resonances from phosphorylethanolamine, phosphorylcholine, inorganic phosphate, phosphodiesters, phosphocreatine, ATP, NAD+, and UDP-N-acetylglucosamine, with phosphorylethanolamine, phosphorylcholine, and ATP being the major metabolites present. The resonances were assigned by making a perchloric acid (PCA) extract of the intact cells and running under high-resolution conditions. The PCA extract spectrum also detected sugar phosphates, ADP and UTP, with the latter being approximately 20% of the nucleotide pool. These studies provide the basis for the study of normal and diseased human RPE cells by NMR spectroscopic methods.


Assuntos
Epitélio Pigmentado Ocular/citologia , Células Cultivadas , Humanos , Espectroscopia de Ressonância Magnética/instrumentação , Fósforo
16.
Int J Epidemiol ; 15(4): 469-76, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3818154

RESUMO

A total of 512 breast cancer patients and 540 controls were compared to examine the risk factors for different categories of breast cancer as defined by age, menopausal status and estrogen receptor (ER) tumor status. Significant differences were found by menopausal status, for age at first birth and age at menarche for all women, and for age at first birth and family history for women between 45 and 54 years old. No significant differences were found with ER status alone; however there was a significant difference between ER status and body weight in premenopausal women; the above significant differences with menopausal status were not found when stratified by ER tumour status. These findings support the hypothesis for aetiological differences for pre- and postmenopausal breast cancer and suggest that ER tumour status may influence the risk associated with body weight.


Assuntos
Neoplasias da Mama/metabolismo , Receptores de Estrogênio/metabolismo , Adulto , Fatores Etários , Idoso , Peso Corporal , Neoplasias da Mama/genética , Feminino , Humanos , Menarca , Menopausa , Pessoa de Meia-Idade , Estudos Retrospectivos , Risco
17.
J Biochem ; 122(4): 717-22, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9399573

RESUMO

Insulin-like growth factor II (IGF-II) is expressed in many developing embryonic tissues and is involved in mammalian growth and development. After birth, serum IGF-II is mainly produced by liver cells. Many reports have indicated that IGF-II is overexpressed in some hepatocellular carcinoma (HCC) tissue. These findings imply the possible importance of this growth factor in carcinogenesis. We screened four human HCC cell lines and three rat HCC cell lines and found that HuH-7 and HepG2 cells produced fivefold more intracellular IGF-II than the other cell lines. Experimental data indicate that IGF-II functions through the intracrine mode for HuH-7 cells. To study whether the overexpression of IGF-II is significant for the growth of HCC or only a consequence of HCC development, we used antisense oligodeoxynucleotides (ATON) to arrest the translation of IGF-II mRNA, and then measured the effects on cell growth. We found that the production of IGF-II was suppressed by ATON, and the decrease of IGF-II resulted in growth inhibition of HuH-7 and HepG2. ATON had no effect on the other tested cell lines, which produced lower levels of IGF-II. The growth inhibition was mainly attributed to a decrease of cell proliferative activity. The results indicate that the IGF-II-overproducing cell lines do depend on IGF-II for growth, and ATON of IGF-II can selectively inhibit the growth of these cells. ATON may be a potential therapeutic agent for this type of HCC in vivo.


Assuntos
Carcinoma Hepatocelular/patologia , Divisão Celular/efeitos dos fármacos , Fator de Crescimento Insulin-Like II/genética , Oligonucleotídeos Antissenso/farmacologia , Animais , Carcinoma Hepatocelular/classificação , Carcinoma Hepatocelular/metabolismo , Humanos , Fator de Crescimento Insulin-Like II/biossíntese , Ratos , Células Tumorais Cultivadas
18.
Surgery ; 112(6): 981-6, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1360713

RESUMO

BACKGROUND: The response of adrenocortical carcinoma (ACC) to adjuvant chemotherapy has been disappointing with no significant impact on survival. The normal adrenal cortex has very high levels of P-glycoprotein, an energy-dependent efflux pump of a variety of structurally unrelated chemotherapeutic agents. P-glycoprotein has been implicated as a cause of multidrug resistance in a variety of neoplasms. The purpose of this study was to evaluate P-glycoprotein expression in ACC. METHODS: Eleven patients with ACC had paraffin-embedded tumor evaluated for P-glycoprotein expression. These were analyzed by immunohistochemistry assay with a battery of four anti-P-glycoprotein antibodies (MRK-16, JSB-1, UIC-2, MDR). RESULTS: All eleven cases showed intense, predominantly membrane immunoreactivity for P-glycoprotein. In 10 of the cases, most tumor cells were immunoreactive with at least three antibodies, and six of 11 cases were positive for all four antibodies. In this small series no correlation existed between P-glycoprotein expression and tumor grade, stage of disease, or survival. CONCLUSIONS: All 11 cases of ACC studied showed P-glycoprotein expression, which was similar to the normal adrenal cortex. This possible mechanism of multidrug resistance may help explain the significant chemoresistance seen in ACC.


Assuntos
Neoplasias do Córtex Suprarrenal/metabolismo , Carcinoma/metabolismo , Resistência a Medicamentos , Glicoproteínas de Membrana/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Adolescente , Neoplasias do Córtex Suprarrenal/patologia , Neoplasias do Córtex Suprarrenal/fisiopatologia , Adulto , Idoso , Carcinoma/patologia , Carcinoma/fisiopatologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias
19.
Biophys Chem ; 76(1): 25-34, 1999 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-10028230

RESUMO

Three triple-helical hairpin DNAs with substitution of 5-bromocytosine for cytosine in different strands have been investigated by molecular mechanics and Raman spectroscopy. The stability of the three substituted triplexes were compared with the corresponding unsubstituted triplex DNA by the molecular mechanics method. Base stacking interactions and strand--strand interactions of each triplex were analyzed in detail. Sugar conformations in these triplexes have been determined by both vibrational spectroscopy and molecular dynamics simulation. The hairpin triplexes with substitution occurring in strand I or both in strands I and III have the main sugar conformation of C3'-endo, while the triplex with substitution occurring in strand III is the combination of C3'-endo and C2'-endo sugar conformation. Theoretical results are basically in agreement with experiments.


Assuntos
Citosina/análogos & derivados , DNA/química , Conformação de Ácido Nucleico , Sequência de Bases , Simulação por Computador , Citosina/química , Análise de Fourier , Análise Espectral Raman , Termodinâmica
20.
Gene Expr ; 8(4): 231-46, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10794525

RESUMO

We have previously reported the cloning of rat deoxyuridine triphosphate nucleotidohydrolase (dUTPase) cDNA and demonstrated that the full-length protein as well as the N-terminal 62-amino acid peptide interacts with peroxisome proliferator-activated receptor alpha (PPARalpha). We now report the cloning of mouse dUTPase cDNA and show that it contains a 162-amino acid open reading frame, encoding a protein with a predicted Mr of 17,400 and differs from rat cDNA, which contains additional 43 amino acids at the N-terminal end. Unlike rat dUTPase, mouse dUTPase failed to bind PPARalpha. An evaluation of 205 amino acid containing rat dUTPase cDNA revealed that the N-terminal 43 extra amino acid segment contains an LXXLL signature motif, considered necessary and sufficient for the binding of several cofactors with nuclear receptors, and its absence in murine dUTPase possibly accounts for the differential binding of these enzymes to PPARalpha. In situ hybridization and immunohistochemical studies revealed that, in the adult mouse, dUTPase is expressed at high levels in proliferating cells of colonic mucosa, and of germinal epithelium in testis. At 9.5-day mouse embryonic development, dUTPase expression is predominantly in developing neural epithelium, and hepatic primordium, and in later developmental stages (11.5-, 13.5-, and 15.5-day embryo), the expression began to be localized to the liver, kidney, gut epithelium, thymus, granular layer of the cerebellum, and olfactory epithelium. We also show that the murine dUTPase gene comprises 6 exons and the 5'-flanking region of -1479 to -27, which exhibited high promoter activity, contains a typical TATA box and multiple cis-elements such as Sp-1, AP2, AP3, AP4, Ker1, RREB, and CREB binding sites. These observations suggest the existence of variants of dUTPase, some of which may influence nuclear receptor function during development and differentiation, in addition to catalyzing the hydrolysis of dUTP to dUMP.


Assuntos
Pirofosfatases/genética , Receptores Citoplasmáticos e Nucleares/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Sítios de Ligação/genética , Clonagem Molecular , Camundongos , Dados de Sequência Molecular , Especificidade de Órgãos , Pirofosfatases/metabolismo , Ratos , Receptores Citoplasmáticos e Nucleares/metabolismo , Alinhamento de Sequência , Análise de Sequência , Especificidade da Espécie
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