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1.
Phys Rev Lett ; 131(16): 162501, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37925694

RESUMO

Neutrinoless double beta decay (0νßß) is a yet unobserved nuclear process that would demonstrate Lepton number violation, a clear evidence of beyond standard model physics. The process two neutrino double beta decay (2νßß) is allowed by the standard model and has been measured in numerous experiments. In this Letter, we report a measurement of 2νßß decay half-life of ^{100}Mo to the ground state of ^{100}Ru of [7.07±0.02(stat)±0.11(syst)]×10^{18} yr by the CUPID-Mo experiment. With a relative precision of ±1.6% this is the most precise measurement to date of a 2νßß decay rate in ^{100}Mo. In addition, we constrain higher-order corrections to the spectral shape, which provides complementary nuclear structure information. We report a novel measurement of the shape factor ξ_{3,1}=0.45±0.03(stat)±0.05(syst) based on a constraint on the ratio of higher-order terms from theory, which can be reliably calculated. This is compared to theoretical predictions for different nuclear models. We also extract the first value for the effective axial vector coupling constant obtained from a spectral shape study of 2νßß decay.

2.
Phys Rev Lett ; 126(18): 181802, 2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-34018798

RESUMO

The CUPID-Mo experiment at the Laboratoire Souterrain de Modane (France) is a demonstrator for CUPID, the next-generation ton-scale bolometric 0νßß experiment. It consists of a 4.2 kg array of 20 enriched Li_{2}^{100}MoO_{4} scintillating bolometers to search for the lepton-number-violating process of 0νßß decay in ^{100}Mo. With more than one year of operation (^{100}Mo exposure of 1.17 kg×yr for physics data), no event in the region of interest and, hence, no evidence for 0νßß is observed. We report a new limit on the half-life of 0νßß decay in ^{100}Mo of T_{1/2}>1.5×10^{24} yr at 90% C.I. The limit corresponds to an effective Majorana neutrino mass ⟨m_{ßß}⟩<(0.31-0.54) eV, dependent on the nuclear matrix element in the light Majorana neutrino exchange interpretation.

3.
Zhonghua Er Ke Za Zhi ; 58(1): 30-34, 2020 Jan 02.
Artigo em Chinês | MEDLINE | ID: mdl-31905473

RESUMO

Objective: To investigate the impact of hypoxic-ischemic brain injury (HIBI) on brain development in neonatal rats of different sexes. Methods: From January 1 to December 31, 2018, 60 7-day-old SD rats were randomly divided into HIBI-F group (20 rats), HIBI-M group (20 rats), and control group (20 rats, 10 females and 10 males). The animal model of HIBI was established with Rice-Vannucci method, with the rats' left common carotid artery double-ligated and severed. The rats were then placed in an incubator and exposed to a hypoxic gas mixture (8% O(2), 92% N(2)) for 90 minutes. No intervention was given to the control group. Two weeks after HIBI, the motor development was evaluated by footprint analysis, the residual brain volume was measured by brain magnetic resonance imaging (MRI), and the damage of synaptic ultra structure was analyzed by transmission electron microscope. One-way ANOVA or χ(2) test was used for inter-group statistical analysis, and paired sample t test was used to compare the bilateral step length and toe distance of rats in the same group. Results: The mortality rate of HIBI-F was significantly higher than that of HIBI-M (20%(4/20) vs. 10%(2/20), χ(2)=40.000, P=0.001). The right step length and toe distance in HIBI-M group and HIBI-F group were significantly shorter than those in control group ((7.5±0.3) cm and (7.9±0.5) cm vs. (8.2±0.5) cm, F=9.605, P<0.01, (0.9±0.1) cm and (1.0±0.0) cm vs. (1.1±0.1) cm, F=71.437, P<0.01). Besides, according to above data, the right step length and toe distance in HIBI-M group were significantly shorter than those in the HIBI-F group (both P<0.01). Furthermore, the right step length was significantly shorter than the left step length ((8.3±0.4) and (8.3±0.5) cm, t=5.289 and 10.580, P=0.001 and 0.010, respectively) and toe distance ((1.1±0.1) and (1.1±0.1) cm, t=7.953 and 6.435, respectively, both P<0.01) in both HIBI-M group and HIBI-F group. Similarly, the synaptic gap of the left precentral gyrus neurons was longer in HIBI-M group and HIBI-F group than that in control group ((23.4±1.3) and (19.7±1.6) nm vs. (18.9±0.6) nm, F=71.719, P<0.01), and also longer in HIBI-M group than that in HIBI-F group (t=7.645, P<0.01). Likewise, the residual brain volume in HIBI-M group and HIBI-F group was significantly less than that in control group ((67±4)% and (75±5)% vs. 100%, F=406.122, P<0.01), and the residual brain volume in HIBI-M group was significantly less than that in HIBI-F group (t=-5.281, P<0.01). Conclusions: Male neonatal rats are more vulnerable to HIBI and have severer subsequent brain injury and hemiplegia. Different treatment strategies for HIBI patients of different sexes should be developed.


Assuntos
Hipóxia-Isquemia Encefálica , Animais , Animais Recém-Nascidos , Encéfalo , Modelos Animais de Doenças , Feminino , Humanos , Hipóxia-Isquemia Encefálica/mortalidade , Masculino , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
4.
Curr Oncol ; 26(5): e658-e664, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31708659

RESUMO

Multimode tumour ablation therapy is a treatment method that combines cryoablation with radiofrequency ablation, guided by medical imaging technology and based on precise planning, targeting, monitoring, and control of the thermal energy delivered, with the aim of achieving a whole-body antitumour immune response to malignant tumours. To develop standardized criteria for the application of multimode tumour ablation therapy to malignant hepatic tumours, to facilitate actualization of the criteria in various hospitals, and to ensure therapeutic efficacy and safety, the Society of Interventional Therapy of the Chinese Anti-Cancer Association and the Solid Tumor Theranostics Committee of the Shanghai Anti-Cancer Association assembled experts who specialize in oncology to discuss this treatment method and to arrive at a clinical practice consensus guideline for the indications, contraindications, and techniques of multimode tumour ablation therapy for malignant hepatic tumours.


Assuntos
Ablação por Cateter , Neoplasias Hepáticas/cirurgia , Cirurgia Assistida por Computador , Consenso , Humanos , Fígado/cirurgia
5.
Clin Radiol ; 74(8): 652.e21-652.e28, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31076083

RESUMO

AIM: To demonstrate the feasibility of magnetic resonance imaging (MRI)-computed tomography (CT) fusion imaging for the assessment of the ablative margin after cryoablation in hepatic malignancies. MATERIALS AND METHODS: This retrospective study analysed 35 patients with 47 liver tumours treated with CT-guided cryoablation. Fusion images of pre-ablation MRI and intraoperative CT data were created on a workstation. Minimal ablative margin (MAM) assessment was categorised into three groups: (I) MAM <0 mm (tumour protruded through the ablation zone), (II) MAM 0-5 mm, and (III) MAM ≥5 mm. Local tumour progression (LTP) was assessed during follow-up. RESULTS: MRI-CT fusion imaging was successfully achieved in 46 (97.9%) of 47 lesions. LTP was detected in 67.4% (31/46) of cases. Twenty-four (77.4%) of 31 LTPs occurred in the subcapsular region of the liver. Using fusion images, the MAM was classified as groups I, II, and III in 18, 25, and three tumours, respectively. In group I, LTP was found in 15 (83.3%) of 18 lesions, whereas in group II, LTP was detected in 16 (64%) of 25 lesions. The cumulative LTP rate in group II was significantly lower than that in group I (p=0.012). CONCLUSION: Pre-ablation MRI and intraoperative CT fusion imaging is feasible and useful for evaluating the MAM of cryoablation in hepatic malignancies.


Assuntos
Criocirurgia/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Imageamento por Ressonância Magnética/métodos , Margens de Excisão , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Estudos de Viabilidade , Humanos , Fígado/diagnóstico por imagem , Fígado/cirurgia , Masculino , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Estudos Retrospectivos
6.
Clin Transl Oncol ; 21(4): 443-450, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30306400

RESUMO

PURPOSE: To evaluate and compare the efficiency and safety of raltitrexed- or floxuridine (FUDR)-based transarterial chemoembolization (TACE) in patients with unresectable colorectal cancer liver metastasis (CRCLM). METHODS: We conducted a retrospective analysis of 81 patients with unresectable CRCLM who failed systemic chemotherapy and were treated with TACE in our department from Oct 2014 to Oct 2017. Of these, 61 patients received TACE using raltitrexed, oxaliplatin, and pirarubicin (raltitrexed group), and 20 received TACE using FUDR, oxaliplatin, and pirarubicin (FUDR group). The objective response rate (ORR), disease control rate (DCR), overall survival (OS, from the first TACE), progression-free survival (PFS, from the first TACE), and adverse reactions were evaluated and compared between the two groups, and prognostic factors for OS were analyzed. RESULTS: The ORRs of the raltitrexed group and FUDR group were 67.2 and 45.0%, respectively (P = 0.076), and the DCRs were 86.9 and 80.0%, respectively (P = 0.452). The median OS (from first TACE) was 14.0 months in the raltitrexed group and 13.0 months in the FUDR group (P = 0.556). The median PFS (from first TACE) was 2.1 months in the raltitrexed group and 2.4 months in the FUDR group (P = 0.878). Univariate and multivariate analyses showed that the primary tumor site, Child-Pugh class, and combination with local ablation (RFA or CRA) were independent significant factors affecting survival. There were no significant differences in adverse reactions between the two groups (P > 0.05), and no treatment-related death occurred in either group. CONCLUSION: TACE treatment based on raltitrexed or FUDR is an efficient and safe alternative choice for treating unresectable CRCLM.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Quimioembolização Terapêutica , Neoplasias Colorretais/patologia , Floxuridina/administração & dosagem , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/terapia , Quinazolinas/administração & dosagem , Tiofenos/administração & dosagem , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Feminino , Floxuridina/efeitos adversos , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Quinazolinas/efeitos adversos , Estudos Retrospectivos , Análise de Sobrevida , Tiofenos/efeitos adversos , Resultado do Tratamento
7.
Zhonghua Liu Xing Bing Xue Za Zhi ; 39(7): 931-936, 2018 Jul 10.
Artigo em Chinês | MEDLINE | ID: mdl-30060307

RESUMO

Objective: To investigate the economic burden of hepatitis C patients and related factors in Guangdong province. Methods: In this study, cluster sampling method was used to select cases, including acute hepatitis C, chronic hepatitis C and liver cirrhosis cases from eligible outpatients and inpatients in 1 or 2 large general hospitals in all the 21 cities in Guangdong province. Questionnaire survey was conducted for all the hepatitis C patients to analyze their economic burden, while multivariate linear regression model was used to identify the related influencing factors. Results: A total of 356 hepatitis C patients were enrolled in the study, with 176 outpatients (49.4%) and 180 inpatients (50.6%) respectively. The average age of the study subjects was (44.79±11.73) year-olds. The annual direct economic costs of patients with acute hepatitis C, chronic hepatitis C and liver cirrhosis were 10 703.22 (IQR: 7 396.75-16 891.91), 14 886.63 (IQR: 7 274.00-30 228.25) and 28 874.00 (IQR: 13 093.69-56 350.00) Yuan (RMB) respectively. The annual indirect costs appeared as 2 426.99 (IQR: 1 912.18-7 354.52), 3 235.99 (IQR: 1 323.81-6 619.07) and 5 442.35 (IQR: 3 235.99-10 296.33) Yuan (RMB) respectively. The annual intangible costs were 5 000.00 (IQR:2 000.00-10 000.00), 10 000.00 (IQR: 4 000.00-30 000.00) and 10 000.00 (IQR: 3 000.00-100 000.00) Yuan (RMB) respectively. The annual total costs were 22 306.17 (IQR: 14 581.24-50 569.17), 38 050.33 (IQR: 17 449.57-68 319.62) and 80 152.18 (IQR: 40 856.09-228 460.79) Yuan (RMB) respectively. Results from the multiple linear regression analysis showed that factors as: annual hospitalization days, annual number of outpatient visits, annual number of hospitalization, type of disease and the levels of the hospitals were related to the economic burden of patients with hepatitis C. Conclusion: Patients with HCV-related diseases presented serious economic problem which calls for close attention in Guangdong province.


Assuntos
Efeitos Psicossociais da Doença , Hepatite C/economia , Cirrose Hepática/economia , Adulto , China/epidemiologia , Cidades , Feminino , Custos de Cuidados de Saúde/estatística & dados numéricos , Hepatite B/epidemiologia , Hepatite C/tratamento farmacológico , Hospitalização , Humanos , Cirrose Hepática/epidemiologia , Masculino , Inquéritos e Questionários
8.
Genet Mol Res ; 14(4): 13247-57, 2015 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-26535638

RESUMO

We aimed to compare the diagnostic value of various detection methods for cytomegalovirus (CMV) infection, to investigate the genetic mechanism associated with CMV infection in pregnant women, and to analyze the risk of sequelae development in fetuses with CMV infection. A total of 300 participants who had the same immunosuppressive regimen and received preemptive therapy for CMV infection were prospectively enrolled in this study; they included 289 vaccine trial participants. The gB-absorbed CMV IgG assay was performed for each vaccine trial participant. The healthy women were divided into 2 groups, and amniotic fluids were collected from them at 15-18 weeks of gestation to test for CMV seropositivity before conception by using IgM specific antibodies, CMV-DNA, and IgG analysis. In 104 cases, cord blood sera and urine specimens were also collected from the infants and examined. The sensitivity and specificity of immediate-early messenger RNA and pp67 (late) messenger RNA detection by the nucleic acid sequence-based amplification technique was comparable to those of virus isolation and PCR. Furthermore, an association between single nucleotide polymorphisms in the TLR-2 gene and congenital CMV infection was observed and confirmed. Moreover, CMV infection during early pregnancy has been shown to have a much more severe effect on the pregnancy outcome compared to infection during later stages of pregnancy.


Assuntos
Infecções por Citomegalovirus/congênito , Infecções por Citomegalovirus/genética , Citomegalovirus , Predisposição Genética para Doença , Complicações Infecciosas na Gravidez/genética , Resultado da Gravidez , Adulto , Alelos , Anticorpos Antivirais/imunologia , Peso ao Nascer , Estudos de Casos e Controles , Citomegalovirus/classificação , Citomegalovirus/genética , Citomegalovirus/imunologia , Infecções por Citomegalovirus/diagnóstico , Infecções por Citomegalovirus/epidemiologia , Infecções por Citomegalovirus/prevenção & controle , Vacinas contra Citomegalovirus/imunologia , Feminino , Frequência do Gene , Genótipo , Idade Gestacional , Humanos , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Recém-Nascido , Masculino , Polimorfismo de Nucleotídeo Único , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/prevenção & controle , Diagnóstico Pré-Natal/métodos , Sensibilidade e Especificidade
9.
Oral Dis ; 16(5): 445-52, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20412454

RESUMO

OBJECTIVE: To investigate the therapeutic effect of herpes simplex virus thymidine kinase (HSV-TK) gene mediated by synthetic radiation-inducible promoters in the treatment of oral squamous cell carcinoma (OSCC) in vitro and in vivo. METHODS: The plasmids pcDNA3.1(+)E6-HSV-TK were constructed, in which the HSV-TK genes were mediated by synthetic radiation-inducible promoters. The recombined plasmids were transfected into the Tca8113 cells and golden hamster buccal carcinoma, respectively. Low-dose radiotherapy was used to upregulate the HSV-TK genes expression. HSV-TK mRNA was assayed by RT-PCR. Apoptosis and proliferating cell nuclear antigen were detected respectively by in situ end-labeling and immunohistochemical method. RESULTS: Compared with control group, the comparative survival rate of Tca8113 cells in HSV-TK/GCV/IR group was markedly decreased and the golden hamster buccal carcinoma in HSV-TK/GCV/IR group was obviously suppressed. Up-regulation of HSV-TK gene expression was found in the Tca8113 cells and in the golden hamster buccal carcinoma resulting from exposure to low-dose irradiation. The apoptosis indexes in Tca8113 cells or golden hamster buccal carcinoma with irradiation were markedly higher than those without irradiation. At the same time, the proliferation indexes in Tca8113 cells or golden hamster buccal carcinoma with irradiation were markedly lower than those without irradiation. CONCLUSION: The results indicate that the synthetic radiation-inducible promoters can serve as a molecular switch to adjust the expression of HSV-TK gene in the treatment of OSCC, and low-dose induction radiation can significantly improve therapeutic efficiency.


Assuntos
Carcinoma de Células Escamosas/terapia , Terapia Genética , Neoplasias Bucais/terapia , Simplexvirus/enzimologia , Timidina Quinase/uso terapêutico , Animais , Apoptose/fisiologia , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular/fisiologia , Cricetinae , Modelos Animais de Doenças , Regulação Enzimológica da Expressão Gênica/genética , Regulação Enzimológica da Expressão Gênica/efeitos da radiação , Vetores Genéticos/genética , Humanos , Neoplasias Bucais/patologia , Plasmídeos/genética , Antígeno Nuclear de Célula em Proliferação/análise , Regiões Promotoras Genéticas/genética , Regiões Promotoras Genéticas/efeitos da radiação , Doses de Radiação , Simplexvirus/genética , Timidina Quinase/genética , Transfecção/métodos , Regulação para Cima/efeitos da radiação
10.
J Am Mosq Control Assoc ; 23(2): 213-9, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17847856

RESUMO

Data on adulticide deposition were collected during studies optimizing aerial ultra-low volume applications and droplet size in the desert environment of the Coachella Valley, Riverside County, California. Pyrenone 25-5 and BVA Spray 13 oil were applied by a single-engine, fixed wing aircraft equipped with 2 Micronair AU5000 atomizers. Data recorded by a portable weather station documented that weather conditions were suitable for application. Adulticide residue was collected using 24-cm-diameter filter papers positioned along 2-3 transects, with 3 positive controls held outside of the treated zone. The trace amounts of 2 major insecticidal components (pyrethrin I and II) and the synergist piperonyl butoxide (PBO) were detected from samples near the center of the spray zone by high-performance liquid chromatography (HPLC); pyrethrin deposition was highest at the center, 156 microg/m2, and it was not detectable 60 m beyond the center of the transect, whereas PBO deposition was 5,000 microg/m2 at the center but was not detectable beyond 150 m. Droplet diameters on spinning Teflon slides were larger than expected for the rated output of the atomizers. For these single swath trials, the lack of swath overlap due to drift resulted in low mortality in sentinel mosquitoes. Detection of residues was limited to the centroid of droplet densities on spinning glass slides and with mortality among sentinel mosquitoes, indicating HPLC may be useful in detecting postspray residues.


Assuntos
Controle de Mosquitos/métodos , Butóxido de Piperonila/química , Piretrinas/química , Aerossóis , California , Estrutura Molecular , Vento
11.
Insect Biochem Mol Biol ; 37(9): 891-902, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17681228

RESUMO

We previously showed that wild-type E3 carboxylesterase of Lucilia cuprina has high activity against Type 1 pyrethroids but much less for the bulkier, alpha-cyano containing Type 2 pyrethroids. Both Types have at least two optical centres and, at least for the Type 1 compounds, we found that wild-type E3 strongly prefers the less insecticidal configurations of the acyl group. However, substitutions to smaller residues at two sites in the acyl pocket of the enzyme substantially increased overall activity, particularly for the more insecticidal isomers. Here we extend these analyses to Type 2 pyrethroids by using fluorogenic analogs of all the diastereomers of cypermethrin and fenvalerate. Wild-type E3 hydrolysed some of these appreciably, but, again, not those corresponding to the most insecticidal isomers. Mutations in the leaving group pocket or oxyanion hole were again generally neutral or deleterious. However, the two sets of mutants in the acyl pocket again improved activity for the more insecticidal acyl group arrangements as well as for the more insecticidal configuration of the cyano moiety on the leaving group. The activities of the best mutant enzyme against the analogs of the most insecticidal isomers of cypermethrin and fenvalerate were more than ten and a hundred fold higher, respectively, than those of wild-type. The implications for resistance development are discussed.


Assuntos
Hidrolases de Éster Carboxílico/genética , Hidrolases de Éster Carboxílico/metabolismo , Muscidae/metabolismo , Piretrinas/farmacocinética , Animais , Isomerismo , Mutação , Piretrinas/síntese química , Relação Estrutura-Atividade
12.
Phys Rev Lett ; 88(6): 062301, 2002 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-11863798

RESUMO

E896 has measured Lambda production in 11.6A GeV/c Au-Au collisions over virtually the whole rapidity phase space. The midrapidity p(t) distributions have been measured for the first time at this energy and appear to indicate that the Lambda hyperons have different freeze-out conditions than protons. A comparison with the relativistic quantum molecular dynamics model shows that while there is good shape agreement at high rapidity the model predicts significantly different slopes of the m(t) spectra at midrapidity. The data, where overlap occurs, are consistent with previously reported measurements.

13.
Phys Rev C Nucl Phys ; 57(4): 1865-78, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11542651

RESUMO

Measurements of dielectron production in p + p and p + d collisions with beamkinetic energies from 1.04 to 4.88 GeV are presented. The differential cross section is presented as a function of invariant pair mass, transverse momentum, and rapidity. The shapes of the mass spectra and their evolution with beam energy provide information about the relative importance of the various dielectron production mechanisms in this energy regime. The p + d to p + p ratio of the dielectron yield is also presented as a function of invariant pair mass, transverse momentum, and rapidity. The shapes of the transverse momentum and rapidity spectra from the p + d and p + p systems are found to be similar to one another for each of the beam energies studied. The beam energy dependence of the integrated cross sections is also presented.


Assuntos
Elétrons , Interações de Partículas Elementares , Partículas Elementares , Íons Pesados , Física Nuclear , Mésons , Aceleradores de Partículas , Espalhamento de Radiação , Análise Espectral
15.
Yao Xue Xue Bao ; 27(6): 472-5, 1992.
Artigo em Chinês | MEDLINE | ID: mdl-1442077

RESUMO

A new C- nor D-homo steroidal alkaloid named zhebeinone was isolated from the bulbs of Fritillaria thunbergii Miq. Its structure was determined by spectral analyses and chemical conversion as 5 alpha, 14 alpha-cevanine-3 beta, 20 beta-dihydroxy-6-one or C-27 epimer of peiminine.


Assuntos
Cevanas/isolamento & purificação , Medicamentos de Ervas Chinesas/química , Cevanas/química , Estrutura Molecular
16.
Bone Miner ; 15(3): 193-207, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1773132

RESUMO

Although the complex effects of glucocorticoids on bone cells have been studied extensively in vitro, little is known about the molecular mechanisms of glucocorticoid responses in osteogenic cells. As c-fos and its protein product are believed to play a key role in intracellular signal transduction, and since their role in regulation of bone formation is well-recognized, we studied the effect of the glucocorticoid analogue dexamethasone (DEX) on the expression of c-fos oncogene in the chick periosteal osteogenesis (CPO) model. C-fos mRNA expression was determined by in situ hybridization at various time points after 10(-7) M DEX treatment. Prior to DEX treatment, the cultures had been synchronized with 2 mM thymidine. The mean area of positively hybridized cells in experimental (DEX-treated) and control (DEX-free) cultures was quantitated by computer assisted morphometry. In DEX-treated cultures c-fos mRNA could be detected transiently and mainly in the osteogenic layer at 30, 45 and 60 min after treatment whereas no c-fos expression could be detected above background level in the control groups. Differences between experimental and control groups were significant (P less than 0.01) as determined by a general linear model (GLM) analysis of variance. These data indicate that in the CPO culture system, DEX (10(-7) M) induces c-fos expression. The findings are compatible with the hypothesis which states that glucocorticoid-induced phenotypic changes in osteogenic cells may be mediated by c-fos.


Assuntos
Dexametasona/farmacologia , Genes fos , Osteogênese , Periósteo/fisiologia , Proteínas Proto-Oncogênicas c-fos/genética , Fosfatase Alcalina/metabolismo , Animais , Divisão Celular , Células Cultivadas , Embrião de Galinha , Expressão Gênica/efeitos dos fármacos , Técnicas In Vitro , Hibridização de Ácido Nucleico , Periósteo/citologia , RNA Mensageiro/genética
17.
Cell Mol Biol ; 35(3): 333-45, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2776175

RESUMO

In earlier publications, we have recorded evidence that micro-injection of globin mRNA from rabbit into goldfish eggs leads to the production of rabbit globin in mature red blood cells of goldfish. This paper is concerned with the mechanism of that apparent transfer of genetic information from the cytoplasm to the nucleus. We investigate the possibility that the injected mRNA is reverse transcribed to create a corresponding cDNA in goldfish eggs. By using purified mRNA from rabbit reticulocytes and micro-injection into enucleated and nucleated goldfish eggs, we show that the production of a DNA sequence hybridizes to cloned cDNA of rabbit globin mRNA and appears to become incorporated into the chromosomes of the developing eggs.


Assuntos
Cromossomos/metabolismo , Globinas/genética , Óvulo/metabolismo , RNA Mensageiro/genética , Transcrição Gênica , Animais , Fracionamento Celular , Núcleo Celular/metabolismo , Citoplasma/metabolismo , DNA/biossíntese , Carpa Dourada , Microinjeções , Hibridização de Ácido Nucleico , Óvulo/crescimento & desenvolvimento , Coelhos
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