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1.
Clin Exp Immunol ; 180(3): 509-19, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25652232

RESUMO

Infants exposed to maternal HIV-1 provide an opportunity to assess correlates of HIV-1-specific interferon (IFN)-γ responses and may be informative in the development of HIV-1 vaccines. HIV-1-infected women with CD4 counts 200-500 cells/mm(3) were randomized to short-course zidovudine/nevirapine (ZDV/NVP) or highly active anti-retroviral therapy (HAART) between 2003 and 2005. Maternal plasma and breastmilk HIV-1 RNA and DNA were quantified during the first 6-12 months postpartum. HIV-1 gag peptide-stimulated enzyme-linked immunospot (ELISPOT) assays were conducted in HIV-1-exposed, uninfected infants (EU), and correlates were determined using regression and generalized estimating equations. Among 47 EU infants, 21 (45%) had ≥1 positive ELISPOT result during follow-up. Infants had a median response magnitude of 177 HIV-1-specific spot-forming units (SFU)/106 peripheral blood mononuclear cells (PBMC) [interquartile range (IQR)=117-287] directed against 2 (IQR = 1-3) gag peptide pools. The prevalence and magnitude of responses did not differ by maternal anti-retroviral (ARV) randomization arm. Maternal plasma HIV-1 RNA levels during pregnancy (P=0.009) and breastmilk HIV-1 DNA levels at 1 month (P=0.02) were associated with a higher magnitude of infant HIV-1-specific ELISPOT responses at 1 month postpartum. During follow-up, concurrent breastmilk HIV-1 RNA and DNA (cell-free virus and cell-associated virus, respectively) each were associated positively with magnitude of infant HIV-1-specific responses (P=0.01). Our data demonstrate the importance of antigenic exposure on the induction of infant HIV-1-specific cellular immune responses in the absence of infection.


Assuntos
Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/imunologia , Leite Humano/virologia , Carga Viral , Adulto , Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Contagem de Linfócito CD4 , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/metabolismo , Humanos , Imunidade Celular , Lactente , Recém-Nascido , Interferon gama/sangue , Quênia , Gravidez , Adulto Jovem
2.
HIV Med ; 15(7): 385-95, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24580813

RESUMO

OBJECTIVES: Adherence is critical for maximizing the effectiveness of pre-exposure prophylaxis (PrEP) in preventing HIV infection. Strategies for promoting adherence to HIV treatment, and their potential application to PrEP adherence, have received considerable attention. However, adherence promotion strategies for prevention medications have not been well characterized and may be more applicable to PrEP. We aimed to identify adherence support interventions that have been effective in other prevention fields and could be applied in the HIV prevention context to support pill taking among PrEP users. METHODS: To identify adherence support interventions that could be evaluated and applied in the PrEP context, we conducted a systematic review across the following prevention fields: hypertension, latent tuberculosis infection, hyperlipidaemia, oral contraceptives, osteoporosis, malaria prophylaxis, and post-exposure prophylaxis for HIV infection. We included randomized controlled trials that evaluated the efficacy of interventions to improve adherence to daily oral medications prescribed for primary prevention in healthy individuals or for secondary prevention in asymptomatic individuals. RESULTS: Our searches identified 585 studies, of which 48 studies met the eligibility criteria and were included in the review; nine evaluated multiple strategies, yielding 64 separately tested interventions. Interventions with the strongest evidence for improving adherence included complex, resource-intensive interventions, which combined multiple adherence support approaches, and low-cost, low-intensity interventions that provided education or telephone calls for adherence support. CONCLUSIONS: Our review identified adherence interventions with strong evidence of efficacy across prevention fields and provides recommendations for evaluating these interventions in upcoming PrEP studies.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/prevenção & controle , Adesão à Medicação , Prevenção Primária , Promoção da Saúde/métodos , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
Phys Rev Lett ; 112(17): 176404, 2014 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-24836262

RESUMO

We employ an exact solution of the simplest model for pump-probe time-resolved photoemission spectroscopy in charge-density-wave systems to show how, in nonequilibrium, the gap in the density of states disappears while the charge density remains modulated, and then the gap reforms after the pulse has passed. This nonequilibrium scenario qualitatively describes the common short-time experimental features in TaS(2) and TbTe(3), indicating a quasiuniversality for nonequilibrium "melting" with qualitative features that can be easily understood within a simple picture.

4.
Plant Dis ; 98(7): 994, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30708915

RESUMO

Mangosteen (Garcinia mangostana L., Guttiferae) is a tropical fruit renowned for its pleasant taste, rich nutrition, and medicinal value. Little research about mangosteen diseases during storage and transport has been reported. In June of 2012, fruit rots on mangosteens imported from Thailand were observed in Guangzhou, China. In infected fruits, pericarps showed an increased firmness, were discolored to deep pink, and the edible aril became brown and rotten. In order to search for the etiological agent of this rot symptom, infected mangosteens were analyzed. Diseased mangosteen tissues were surface-sterilized with 70% alcohol, then with 0.1% HgCl2, dipped in sterilized water three times, and placed onto potato dextrose agar (PDA) at 26°C. The fungi isolated from tissues of the pericarp and aril were similar in morphology and grew rapidly, covering the plate surface (9 mm diameter) after 2 to 3 days of incubation at 26°C. The morphological characters of 10 single-spore isolates were observed. These isolates showed light yellow to light brown fertile colonies on PDA. On corn meal agar (CMA), conidiophores were erect, arising from wide hyphae; they were composed of a basal stipe ending in a penicillate conidiogenous apparatus with directly subtending sterile stipe extensions ranging from 74.5 to 195.0 µm long. Conidia were unicellular, smooth, oblong to elliptical, 6.3 to 8.5 × 2.5 to 3.0 µm, and accumulated in a mucilaginous mass. Chlamydospores were multicellular, dark brown, regular in shape and thick-walled, and 40.0 to 52.5 µm in diameter. On the basis of these morphological characters, these isolates were identified as Gliocephalotrichum bulbilium (2). To confirm the identity of this fungus, genomic DNA of two isolates was extracted, and fragments of ITS region and ß-tubulin gene were amplified by PCR, sequenced, and compared with sequences of Gliocephalotrichum species available in NCBI GenBank. Both DNA regions (GenBank Accession Nos. KF716166 and KF716168) had sequence similarities of 99% and 97%, respectively, to other G. bulbilium sequences at GenBank. Pathogenicity tests were conducted on three detached fruits for two isolates. Fruits were inoculated using 5-mm mycelial disks with conidia taken from 3-day-old cultures of G. bulbilium isolate Gb1 and Gb10 grown on PDA. Controls were inoculated with PDA disks only. All treated fruits were kept individually in a humid chamber at 26°C. Tests were repeated twice. Three days after inoculation, white mycelial growth for Gb was observed at inoculation sites. Eight days after inoculation, mycelium of Gb nearly covered the fruit, causing fruit rot, and the pericarp became hard and light in color. The control fruit did not rot. G. bulbilium was re-isolated from diseased plant tissue, thus fulfilling Koch's postulates. G. bulbilium has been reported causing postharvest fruit rot of rambutan (Nephelium lappaceum) and guava (Psidium guajava) in some locations (3,4). Moreover, the fungus caused cranberry fruit rot in the United States (1). To our knowledge, this is the first report of G. bulbilium causing postharvest fruit rot of mangosteen in China. It is uncertain whether the fungus infected mangosteen in Thailand and was carried to China due to commercial relationship. References: (1) C. Constantelos et al. Plant Dis. 95:618, 2011. (2) C. Decock et al. Mycologia 98:488, 2006. (3) L. M. Serrato-Diaz et al. Plant Dis. 96:1225, 2012. (4) A. Sivapalan et al. Australas. Plant Pathol. 27:274, 1998.

5.
Mol Biol (Mosk) ; 48(4): 682-6, 2014.
Artigo em Russo | MEDLINE | ID: mdl-25842852

RESUMO

The aim of the study was to explore the interactions of human papilloma virus 16 (HPV16) E2 protein and Daxx. The location or co-localization of PML and E2 with Daxx in Caski cells was observed by indirect immunofluorescence test. The interaction of E2 and Daxx was analyzed by co-immunoprecipitation, Western-blot and yeast-two hybrid assay. In Caski cells the fluorescence of Daxx or PML was mainly distributed in the cytoplasm or nucleus, respectively, and in the align image their signals did not overlapped. However, when the red signal of HPV16 E2 and the green signal of Daxx in cyto- plasm of Caski cells were merged, the yellow signals appeared. The yeast co-transformed with pGBKT7/Daxx and pGADT7/E2 or pGADT7/E2 TAD can grow onto SD/-Trp-Leu-His and SD/-Trp-Leu-His-Ade plates. So Daxx wasn't co-located with PML but with HPV16 E2 mainly in the cytoplasm of Caski cells. On the base of the results one can propose that HPV16 E2, in particularly its transcription-activity domain (TAD), interacts with Daxx.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Oncogênicas Virais/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Western Blotting , Linhagem Celular , Núcleo Celular/metabolismo , Proteínas Correpressoras , Citoplasma/metabolismo , Proteínas de Ligação a DNA/genética , Humanos , Imunoprecipitação , Chaperonas Moleculares , Mutação , Proteínas Nucleares/genética , Proteínas Oncogênicas Virais/genética , Proteína da Leucemia Promielocítica , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Técnicas do Sistema de Duplo-Híbrido
6.
J Nanosci Nanotechnol ; 12(8): 6480-3, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22962769

RESUMO

In this paper, we use a simple and highly-effective pulsed laser reducing method to fabricate flexible, transparent and conducting graphene film. The pulsed laser reducing process was monitored by digital camera and UV-visible spectroscopy. The obtained reduced graphene oxide (r-GO) was characterized by Raman spectroscopy. Based on this reducing method, the resulting r-GO films possessed a transmittance varied from 29% to 74% and a sheet resistance varied from 2.1 MΩ/[square] to 840 Ω/[square], which was very close to chemically r-GO film.

7.
J Anim Breed Genet ; 129(4): 257-70, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22775258

RESUMO

Theory hypothesizes that the rate of decline in linkage disequilibrium (LD) as a function of distance between markers, measured by r(2), can be used to estimate effective population size (N(e)) and how it varies over time. The development of high-density genotyping makes feasible the application of this theory and has provided an impetus to improve predictions. This study considers the impact of several developments on the estimation of N(e) using both simulated and equine high-density single-nucleotide polymorphism data, when N(e) is assumed to be constant a priori and when it is not. In all models, estimates of N(e) were highly sensitive to thresholds imposed upon minor allele frequency (MAF) and to a priori assumptions on the expected r(2) for adjacent markers. Where constant N(e) was assumed a priori, then estimates with the lowest mean square error were obtained with MAF thresholds between 0.05 and 0.10, adjustment of r(2) for finite sample size, estimation of a [the limit for r(2) as recombination frequency (c) approaches 0] and relating N(e) to c (1 - c/2). The findings for predicting N(e) from models allowing variable N(e) were much less clear, apart from the desirability of correcting for finite sample size, and the lack of consistency in estimating recent N(e) (<7 generations) where estimates use data with large c. The theoretical conflicts over how estimation should proceed and uncertainty over where predictions might be expected to fit well suggest that the estimation of N(e) when it varies be carried out with extreme caution.


Assuntos
Desequilíbrio de Ligação , Modelos Genéticos , Animais , Frequência do Gene/genética , Marcadores Genéticos/genética , Técnicas de Genotipagem , Cavalos/genética , Polimorfismo de Nucleotídeo Único/genética , Densidade Demográfica
8.
Genet Res (Camb) ; 92(2): 157-66, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20515518

RESUMO

The incorporation of genetic information such as quantitative trait loci (QTL) data into breeding schemes has become feasible as DNA technologies have advanced. Such strategies allow the frequency of desirable QTL to be controlled over a predefined time frame, allowing the allele trajectory for QTL to be manipulated. A continuous approximation to changes in allele frequency was developed to approximate the selection procedure as a continuous rather than a discrete process, and analytical solutions were obtained, which shed light on how allele trajectories behave under different objective functions. Three different objectives were considered: (1) minimizing the total selection intensity, (2) minimizing the sum of squared selection intensities and (3) equalizing the selection intensity applied over time. Simulations and genetic algorithms were performed to test the accuracy and robustness of the continuous approximation. Theory shows firstly that the total selection intensity required for moving an allele from a starting frequency to another frequency point can be predicted independent of its trajectory, and secondly that objectives (2) and (3) are equivalent as the number of selection opportunities (T) becomes large. The prediction of total selection intensity provides a good fit for these two objectives, with the accuracy of prediction improving as T increases. However, for (1) the continuous approximation does not fit due to the existence of a discontinuous solution in which the continuous approximation is applied before the frequency of the selected allele reaches 0.5 followed by rapid fixation.


Assuntos
Alelos , Locos de Características Quantitativas/genética , Animais , Cruzamento , Simulação por Computador , Frequência do Gene , Genética Populacional
9.
Anaesth Rep ; 8(2): 135-137, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33210091

RESUMO

Myotonic dystrophy type 1 is the most common muscular dystrophy in adults. Anaesthetic management should take into consideration the numerous body systems affected, including the musculoskeletal; respiratory; cardiovascular; gastro-intestinal; and central nervous systems. A 42-year-old man with myotonic dystrophy presented for septoplasty and bilateral inferior turbinate reductions. He had severe upper and lower extremity myotonia and weakness, pulmonary impairment with non-obstructive patterns and first-degree atrioventricular block with reduced ejection fraction. He used bilevel positive airway pressure, a cough assist device and was paced 3% of the time with a single-chamber pacemaker. To reduce potential complications associated with opioid use and general anaesthetics, an opioid-free technique was planned using local anaesthetic infiltration and sedation with a dexmedetomidine infusion. The patient maintained spontaneous ventilation and haemodynamic stability, and had an uneventful postoperative course. Dexmedetomidine is a highly selective α2-adrenergic receptor agonist that has the ability to provide sedation, analgesia and anxiolysis with a stable haemodynamic profile. Avoiding both opioids and general anaesthetics in these patients may decrease the risk of peri-operative complications.

10.
J Cell Biol ; 88(1): 89-95, 1981 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-6110670

RESUMO

The uptake, metabolism, and action of cAMP, captured within phospholipid vesicles, in H-35 hepatoma cells were studied. Sonication of lipids in buffer containing cAMP resulted in the formation of 300-A unilamellar lipid vesicles, capturing cAMP in the internal aqueous cavity. Incubation of H-35 hepatoma cells with vesicles containing cAMP (vesicle-cAMP) resulted in rapid incorporation of the vesicle content; apparent saturation of uptake was reached after approximately 30 min of incubation at 37 degrees C. Uptake of vesicle-cAMP was linear over a 10-fold vesicle concentration range. Pretreatment of cells with combined inhibitors of glycolysis and respiration inhibited vesicle uptake by 27%, suggesting vesicle fusion with the cell membrane as a predominant pathway of vesicle uptake. Studies on the metabolism of incorporated cAMP indicated that greater than 50% of the cell-associated radioactivity, derived from vesicle-[3H]cAMP, was preserved as cAMP at the end of a 20-min incubation at 37 degrees C. The incorporation of vesicle-cAMP by H-35 hepatoma cells resulted in increased tyrosine aminotransferase (TAT) activity. The concentration of vesicle-cAMP needed to produce a half-maximal increase in TAT activity was 10 microM, approximately two orders of magnitude lower than that of exogenously added dbcAMP. cAMP was ineffective when added extracellularly. The kinetic relationship of the cAMP-induced increase in TAT activity and the binding of cAMP to its receptor protein, in intact H-35 cells, was examined using vesicle-trapped 8-N3-cAMP, a photoaffinity labeling analogue of cAMP. Incubation of H-35 hepatoma cells with vesicle-8-N3-cAMP resulted in increased TAT activity, preceded by the binding of 8-N3-cAMP to the regulatory subunit of type II cAMP-dependent protein kinase. The use of lipid vesicles provides a means of modulating intracellular cAMP concentration without adding cyclic nucleotide in the millimolar concentration range to the extracellular medium. The increased efficiency of intracellular delivery of cyclic nucleotide with retention of biological activity, provides a useful technique in examining the relationship of occupancy of specific cAMP-receptor protein(s) and the occurrence of a cAMP-mediated biological response in intact cells.


Assuntos
Proteína Receptora de AMP Cíclico , AMP Cíclico , Tirosina Transaminase/biossíntese , Animais , Bucladesina , Carcinoma Hepatocelular , Proteínas de Transporte/metabolismo , Linhagem Celular , Membrana Celular/metabolismo , AMP Cíclico/metabolismo , Indução Enzimática , Cinética , Lipossomos/metabolismo , Neoplasias Hepáticas , Ratos
11.
Science ; 245(4920): 841-2, 1989 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-17773359

RESUMO

An empirical model and an ab initio calculation of the bulk moduli for covalent solids are used to suggest possible new hard materials. The empirical model indicates that hypothetical covalent solids formed between carbon and nitrogen are good candidates for extreme hardness. A prototype system is chosen and a first principles pseudopotential total energy calculation on the system is performed. The results are consistent with the empirical model and show that materials like the prototype can have bulk moduli comparable to or greater than diamond. It may be possible to synthesize such materials in the laboratory.

12.
Science ; 214(4522): 799-800, 1981 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-6117128

RESUMO

Various lectins were found to induce tyrosine aminotransferase in H-35 rat hepatoma cells grown in monolayer culture. Wheat germ agglutinin gave a maximal induction of tyrosine aminotransferase 6 hours after its addition. The induction time course was similar to that elicited by insulin. Fourteen micrograms of wheat germ agglutinin per milliliter gave half-maximal enzyme induction and 50 micrograms per milliliter gave the maximal response. The induction of tyrosine aminotransferase by wheat germ agglutinin was additive with the induction by either dexamethasone or dibutyryl adenosine 3',5'-monophosphate, but was not additive with the tyrosine amino transferase induction by insulin. Wheat germ agglutinin also mimicked insulin in the inhibition of cellular protein degradation in the absence of serum. The insulin-like effects of lectins should be considered in lectin-mediated manipulations such as agglutination.


Assuntos
Insulina/farmacologia , Lectinas/farmacologia , Fígado/enzimologia , Tirosina Transaminase/biossíntese , Animais , Bucladesina/farmacologia , Células Cultivadas , Dexametasona/farmacologia , Indução Enzimática/efeitos dos fármacos , Neoplasias Hepáticas Experimentais/enzimologia , Peptídeo Hidrolases/metabolismo , Ratos , Receptor de Insulina/efeitos dos fármacos
13.
Science ; 196(4286): 192-5, 1977 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-847466

RESUMO

Rabbit alpha globin gene copies have been made, using reverse transcriptase and DNA polymerase I, and cloned in bacterial plasmids. Plasmid pHb72 has been shown to contain the alpha gene sequence by restriction enzyme analysis and nucleotide sequencing studies, and therefore has been approved for propagation under P2 plus EK1 conditions by the National REcombinant DNA Committee.


Assuntos
DNA Recombinante/análise , Herança Extracromossômica , Genes , Globinas , Plasmídeos , Sequência de Bases , Enzimas de Restrição do DNA , DNA Recombinante/metabolismo , RNA Mensageiro/análise , Projetos de Pesquisa/normas
14.
Science ; 248(4954): 462-5, 1990 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-17815595

RESUMO

Measurements of the melting temperature of lead, carried out to pressures of 1 megabar (10(11) pascal) and temperatures near 4000 kelvin by means of a laser-heated diamond cell, are in excellent agreement with the results of previous shock-wave experiments. The data are analyzed by means of first principles quantum mechanical calculations, and the agreement documents the reliability of current experimental and theoretical techniques for studies of melting at ultrahigh pressures. These studies have potentially wide-ranging applications, from planetary science to condensed matter physics.

15.
J Natl Cancer Inst ; 89(18): 1356-60, 1997 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-9308705

RESUMO

BACKGROUND: For women with ductal carcinoma in situ (DCIS) of the breast who have been treated with breastconserving surgery, the usefulness of size and surgical margin status (i.e., presence or absence of disease at the point of excision) as prognostic factors for predicting residual disease has not been well established. This study was conducted to determine more clearly the relationship between size and margin status of mammary DCIS to residual disease. METHODS: The pathology records of 232 consecutive patients with mammary DCIS who had been initially treated with lumpectomy at the University Hospitals of Cleveland were retrospectively reviewed. The size of the DCIS and the surgical margins of lumpectomy were analyzed. Residual disease was defined as the persistence of DCIS in the re-excision and/or mastectomy specimens. RESULTS: Residual disease was found in 15 of 101 patients with DCIS of less than 1.0 cm in longest dimension, in 27 of 96 patients with DCIS of 1.0-2.4 cm in size, and in 24 of 35 patients with DCIS of greater than or equal to 2.5 cm in size (P<.001). Residual disease was found in 30 of 77 patients with DCIS and positive margins, in 11 of 59 patients with DCIS and close margins (< or =1mm), and in 10 of 73 patients with DCIS and negative margins (>1 mm) (P =.001). In multivariate analysis, the occurrence of residual disease was associated with large tumor size (i.e., > or =2.5 cm) (odds ratio [OR] = 7.7; 95% confidence interval [CI] = 3.13-20.00; two-sided P = .0001) and with positive margin status (OR = 2.2; 95% CI = 1.02-4.55; two-sided P = .04). CONCLUSIONS: The size and margin status of DCIS each were found to be independent predictors of residual disease.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma in Situ/patologia , Carcinoma in Situ/cirurgia , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/cirurgia , Mastectomia Segmentar , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Neoplasia Residual , Razão de Chances , Valor Preditivo dos Testes , Prognóstico
16.
Cancer Res ; 60(13): 3429-34, 2000 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-10910052

RESUMO

The expression of 119 cell surface molecules was catalogued for three prostate cancer cell lines, LNCaP, PC3, and DU145, all of which were established from metastases. Many of these molecules are common to all three cell lines, whereas some are differentially expressed. More prostate basal epithelial cell-specific than luminal epithelial cell-specific molecules are detected, especially in DU145 and PC3 cells. The cancer cells also express molecules that are not normally associated with prostate epithelial cells. As a population, expression of these molecules appears to be heterogeneous. This heterogeneity may be an inherent property of the population.


Assuntos
Antígenos CD/análise , Antígenos de Superfície/análise , Neoplasias da Próstata/patologia , Antígenos CD/genética , Antígenos de Neoplasias/análise , Antígenos de Neoplasias/genética , Antígenos de Superfície/genética , Citometria de Fluxo , Humanos , Masculino , Neoplasias da Próstata/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
17.
Cancer Res ; 51(15): 4107-10, 1991 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-1713126

RESUMO

A complementary DNA clone containing human endogenous retrovirus-like sequences spliced to sequences encoding human calbindin was discovered by complementary DNA subtraction analysis between two human prostate cell lines, PC3 and DU145. This gene is presumably activated by the long terminal repeat of the retrovirus-like sequence. It belongs to a member of the retrovirus-like H (tRNA(his) primer binding sequence) family. The level of this transcript is high in PC3, derived from a prostate bone metastasis, but not in DU145, derived from a prostate brain metastasis.


Assuntos
DNA/genética , Neoplasias da Próstata/genética , Retroviridae/genética , Proteína G de Ligação ao Cálcio S100/genética , Idoso , Sequência de Bases , Calbindinas , Clonagem Molecular/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Poli A/genética , RNA/genética , RNA Mensageiro , Retinoblastoma/genética , Transcrição Gênica/genética , Células Tumorais Cultivadas
18.
Cancer Res ; 53(11): 2460-5, 1993 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-7684318

RESUMO

The steady-state level of mitochondrial hinge protein (hinge) RNA is elevated in various cell lines established from human tumors compared to that in normal cells or cells treated with mitogen. Sequences upstream of the hinge gene were cloned and determined. A number of potential protein factor binding DNA elements are present in this region, one of which may possess transcription enhancer-like properties for respiratory chain genes. This element is actually located within the highly repetitive human Alu sequences.


Assuntos
DNA de Neoplasias/química , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias/genética , Proteínas/genética , RNA/genética , Sequência de Bases , Regulação para Baixo , Complexo III da Cadeia de Transporte de Elétrons , Fibroblastos/metabolismo , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Leucemia de Células T/genética , Leucemia de Células T/metabolismo , Linfócitos/metabolismo , Masculino , Dados de Sequência Molecular , Neoplasias/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Proteínas/metabolismo , RNA/metabolismo , Análise de Sequência de DNA , Células Tumorais Cultivadas
19.
Cancer Res ; 40(11): 4100-8, 1980 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6258772

RESUMO

The regulation of cyclic adenosine 3':5'-monophosphate (cAMP)-binding protein in N-18 neuroblastoma cells in tissue culture was studied by the covalent incorporation of 8-azido-cyclic adenosine 3':5'-[32P]monophosphate, together with the techniques of sodium dodecyl sulfate:polyacrylamide gel electrophoresis and autoradiography. Greater than 95% of the total cAMP binding activity of N-18 neuroblastoma cells was identified as being regulatory subunits of the type I (RI) and type II (RII) species, with RI being the predominant form of the two (RI:RII = 3:1). The specific activity of RI but not of RII increased 3-fold when cells were grown in medium containing 1% rather than 10% fetal calf serum. Under the same conditions, the specific activity of acetylcholinesterase increased 3- to 5-fold. The increase in RI was inversely related to the serum concentration in the medium and was specific for cells at the stationary phase of growth. An increase in intracellular cAMP, concomitant with the increase in RI, was also observed. Morphological examination of stationary-phase neuroblastoma cells maintained in medium containing 1% fetal calf serum suggested the presence of a high proportion of highly-differentiated cells. It is proposed that the regulatory control of RI cAMP-binding protein by serum may involve modulation of intracellular cAMP and that the expression RI may be used as a biochemical index of differentiation in mouse neuroblastoma cells.


Assuntos
Azidas , Proteínas de Transporte/metabolismo , Proteína Receptora de AMP Cíclico , AMP Cíclico/metabolismo , Neuroblastoma/metabolismo , Animais , Diferenciação Celular , Divisão Celular , Células Cultivadas , Meios de Cultura , AMP Cíclico/análogos & derivados , Citosol/metabolismo , Substâncias de Crescimento/sangue , Cinética , Camundongos , Peso Molecular , Neoplasias Experimentais/metabolismo
20.
Cancer Res ; 43(6): 2812-8, 1983 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6303569

RESUMO

(R, S)-alpha-Fluoromethylornithine (alpha-FMO), a catalytic irreversible inhibitor of ornithine decarboxylase (L-ornithine carboxy-lyase, EC 4.1.1.17), induced the differentiation of N2a mouse neuroblastoma cells. The effect of alpha-FMO was concentration dependent; approximately 50% of the cell population exhibited neurite outgrowth in the presence of 1 mM alpha-FMO, while higher concentrations caused severe growth inhibition and cell death. The effect of 1 mM alpha-FMO on neuroblastoma differentiation was potentiated greatly by 0.1 to 0.2 mM N6,O2'-dibutyryl adenosine cyclic 3':5'-monophosphate (Bt2cAMP) causing more than 90% of the cell population to differentiate morphologically with thick and long processes; 0.1 to 0.2 mM Bt2cAMP, by itself, had no effect on cell growth and did not induce neurite outgrowth. The effect of alpha-FMO, either by itself or in combination with 0.1 to 0.2 mM Bt2cAMP, on the morphological differentiation of mouse neuroblastoma cells was reversed by the addition of exogenous putrescine or spermidine. The morphological differentiation of mouse neuroblastoma cells induced by 1 mM alpha-FMO plus 0.2 mM Bt2cAMP was accompanied by increases of the regulatory subunit of the type I cAMP-binding protein and acetylcholinesterase activity. These results indicate that the modulation of cellular polyamine contents may be important in neuroblastoma cell differentiation.


Assuntos
Carboxiliases/antagonistas & inibidores , Neuroblastoma/patologia , Inibidores da Ornitina Descarboxilase , Ornitina/análogos & derivados , Acetilcolinesterase/metabolismo , Animais , Bucladesina/farmacologia , Diferenciação Celular/efeitos dos fármacos , Sinergismo Farmacológico , Eflornitina , Camundongos , Neuroblastoma/enzimologia , Ornitina/farmacologia , Poliaminas/metabolismo
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