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1.
Ultrasound Obstet Gynecol ; 63(2): 258-262, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37740663

RESUMO

OBJECTIVE: To evaluate the changes in the ultrasound characteristics of decidualized non-ovarian endometriotic lesions that occur during pregnancy and after delivery. METHODS: This was a prospective observational cohort study carried out at a single tertiary center between December 2018 and October 2021. Pregnant women with endometriosis underwent a standardized transvaginal ultrasound examination with color Doppler imaging once in every trimester and after delivery. Non-ovarian endometriotic lesions were measured and evaluated by subjective semiquantitative assessment of blood flow. Lesions with moderate-to-marked blood flow were considered decidualized. The size and vascularization of decidualized and non-decidualized lesions were compared between the gravid state and after delivery. Only patients with non-ovarian endometriotic lesion(s) who underwent postpartum examination were included in the final analysis. RESULTS: Overall, 26 pregnant women with a surgical or sonographic diagnosis of endometriosis made prior to conception were invited to participate in the study, of whom 24 were recruited. Of those, 13 women with non-ovarian endometriosis who attended the postpartum examination were included. In 7/13 (54%) cases, the lesion(s) were decidualized. In 4/7 (57%) women with decidualized lesion(s), the size of the largest lesion increased during pregnancy, while in 3/7 (43%), the size was unchanged. The size of non-decidualized lesions did not change during pregnancy. On postpartum examination, only seven lesions were observed, of which three were formerly decidualized and four were formerly non-decidualized. Lesions that were detected after delivery appeared as typical endometriotic nodules and were smaller compared with during pregnancy. The difference in maximum diameter between the gravid and postpartum states was statistically significant in decidualized lesions (P < 0.01), but not in non-decidualized lesions (P = 0.09). The reduction in mean diameter was greater in decidualized compared with non-decidualized lesions (P = 0.03). CONCLUSIONS: Decidualization was observed in 54% of women with non-ovarian endometriotic lesion(s) and resolved after delivery. Our findings suggest that the sonographic features of decidualization, which might mimic malignancy, are pregnancy-related and that expectant management and careful monitoring should be applied in these cases. Clinicians should be aware of the changes observed during pregnancy to avoid misdiagnosing decidualized lesions as malignancy and performing unnecessary surgery. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Endometriose , Neoplasias Ovarianas , Feminino , Humanos , Gravidez , Masculino , Endometriose/diagnóstico por imagem , Endometriose/patologia , Neoplasias Ovarianas/patologia , Estudos Prospectivos , Ultrassonografia , Período Pós-Parto
2.
Phys Rev Lett ; 121(17): 172501, 2018 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-30411940

RESUMO

Observation of neutrinoless double beta decay, a lepton number violating process that has been proposed to clarify the nature of neutrino masses, has spawned an enormous world-wide experimental effort. Relating nuclear decay rates to high-energy, beyond the standard model (BSM) physics requires detailed knowledge of nonperturbative QCD effects. Using lattice QCD, we compute the necessary matrix elements of short-range operators, which arise due to heavy BSM mediators, that contribute to this decay via the leading order π^{-}→π^{+} exchange diagrams. Utilizing our result and taking advantage of effective field theory methods will allow for model-independent calculations of the relevant two-nucleon decay, which may then be used as input for nuclear many-body calculations of the relevant experimental decays. Contributions from short-range operators may prove to be equally important to, or even more important than, those from long-range Majorana neutrino exchange.

3.
Nature ; 558(7708): 91-94, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29849150

RESUMO

The axial coupling of the nucleon, gA, is the strength of its coupling to the weak axial current of the standard model of particle physics, in much the same way as the electric charge is the strength of the coupling to the electromagnetic current. This axial coupling dictates the rate at which neutrons decay to protons, the strength of the attractive long-range force between nucleons and other features of nuclear physics. Precision tests of the standard model in nuclear environments require a quantitative understanding of nuclear physics that is rooted in quantum chromodynamics, a pillar of the standard model. The importance of gA makes it a benchmark quantity to determine theoretically-a difficult task because quantum chromodynamics is non-perturbative, precluding known analytical methods. Lattice quantum chromodynamics provides a rigorous, non-perturbative definition of quantum chromodynamics that can be implemented numerically. It has been estimated that a precision of two per cent would be possible by 2020 if two challenges are overcome1,2: contamination of gA from excited states must be controlled in the calculations and statistical precision must be improved markedly2-10. Here we use an unconventional method 11 inspired by the Feynman-Hellmann theorem that overcomes these challenges. We calculate a gA value of 1.271 ± 0.013, which has a precision of about one per cent.

4.
Phys Rev Lett ; 115(17): 171803, 2015 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-26551103

RESUMO

We calculate the spin-independent scattering cross section for direct detection that results from the electromagnetic polarizability of a composite scalar "stealth baryon" dark matter candidate, arising from a dark SU(4) confining gauge theory-"stealth dark matter." In the nonrelativistic limit, electromagnetic polarizability proceeds through a dimension-7 interaction leading to a very small scattering cross section for dark matter with weak-scale masses. This represents a lower bound on the scattering cross section for composite dark matter theories with electromagnetically charged constituents. We carry out lattice calculations of the polarizability for the lightest "baryon" states in SU(3) and SU(4) gauge theories using the background field method on quenched configurations. We find the polarizabilities of SU(3) and SU(4) to be comparable (within about 50%) normalized to the stealth baryon mass, which is suggestive for extensions to larger SU(N) groups. The resulting scattering cross sections with a xenon target are shown to be potentially detectable in the dark matter mass range of about 200-700 GeV, where the lower bound is from the existing LUX constraint while the upper bound is the coherent neutrino background. Significant uncertainties in the cross section remain due to the more complicated interaction of the polarizablity operator with nuclear structure; however, the steep dependence on the dark matter mass, 1/m(B)(6), suggests the observable dark matter mass range is not appreciably modified. We briefly highlight collider searches for the mesons in the theory as well as the indirect astrophysical effects that may also provide excellent probes of stealth dark matter.

5.
Hum Reprod ; 29(12): 2787-93, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25240011

RESUMO

STUDY QUESTION: Is endometrial thickness measured prior to embryo transfer associated with placenta praevia? SUMMARY ANSWER: Following IVF, the risk of placenta praevia is increased 4-fold in women with an endometrial thickness of >12 mm compared with women with an endometrial thickness of <9 mm. WHAT IS KNOWN ALREADY: Placenta praevia is a serious complication of pregnancy with adverse maternal and neonatal outcomes. Placenta praevia is 2- to 6-fold more likely to occur following IVF treatment but it remains unknown what factors contribute to that increased risk. STUDY DESIGN, SIZE, DURATION: Retrospective cohort study involving 4007 women who had 4537 singleton assisted reproduction technology (ART) births occurring between January 2006 and June 2012 with no loss to follow-up. The primary outcome measure was the diagnosis of placenta praevia, made by the treating obstetrician on a transvaginal ultrasound in the third trimester. PARTICIPANTS/MATERIALS, SETTING, METHODS: Women who had singleton births following single embryo transfer performed at Monash IVF in Melbourne, Australia were included. Of the 4537 cycles leading to a singleton ART birth, 2951 were stimulated cycles with fresh embryo transfers; 355 were hormone replacement therapy frozen embryo transfers and 1231 were natural cycles with frozen embryo transfers. The dataset was analysed using binary logistic general estimating equations to calculate odds ratios for placenta praevia adjusted (aOR) for known confounders. MAIN RESULTS AND THE ROLE OF CHANCE: The study groups did not differ significantly in age, BMI and aetiologies of infertility prior to IVF treatment. When compared with stimulated cycles, placenta praevia was less common in women undergoing natural cycles with frozen embryo transfers (OR 0.44, 95% confidence interval (CI) 0.27-0.70, P < 0.01) but hormone replacement therapy frozen embryo transfer cycles were not associated with a lower risk (OR 0.89, 95% CI 0.48-1.63). After adjusting for confounders, smoking (aOR 2.58, 95% CI 1.07-6.24, P = 0.04, endometriosis (aOR 2.01, 95% CI 1.21-3.33, P < 0.01) and endometrial thickness remained statistically significant as independent risk factors for placenta praevia. Compared with women with an endometrial thickness of <9 mm, women with an endometrial thickness of 9-12 mm had an aOR of 2.02 (95% CI 1.12-3.65, P = 0.02) and women with an endometrial thickness >12 mm had an aOR of 3.74 (95% CI 1.90-7.34, P < 0.01). These differences remained statistically significant after performing a sensitivity analysis limited to women with no previous births. LIMITATIONS, REASONS FOR CAUTION: The study is retrospective in nature, not all confounders may have been accounted for and details on previous intrauterine surgery, a known risk factor, were not available. In addition, ultrasound assessments were carried out by several highly trained operators measuring the endometrial thickness, the main independent variable, in a two-dimensional plane and some inter-observer variability may therefore be present. WIDER IMPLICATIONS OF THE FINDINGS: The findings of a higher risk of placenta praevia in patients with endometriosis and in those that smoke are in agreement with the current literature on natural conception. There have so far been no reports of an association between endometrial thickness and placenta praevia after ART. This novel finding warrants further study to elucidate the underlying cause of the association and to assess how to minimize harm to IVF patients and their offspring. The fact that the observed increased risk is not linked to the type of embryo transfer (fresh/frozen) but to the type of endometrial preparation, suggests that the risk of placenta praevia in ART can be reduced by considering an elective frozen embryo transfer in a natural cycle, especially given the growing evidence that this strategy also provides a number of other maternal and neonatal benefits. STUDY FUNDING/COMPETING INTERESTS: No funding was required for this study. L.R. has a minority shareholding in Monash IVF and has received unconditional research and educational grants from MSD, Merck-Serono and Ferring. L.R. serves on an advisory board for MSD and Ferring.


Assuntos
Endométrio/patologia , Placenta Prévia/epidemiologia , Técnicas de Reprodução Assistida , Endométrio/diagnóstico por imagem , Feminino , Humanos , Placenta Prévia/diagnóstico por imagem , Placenta Prévia/patologia , Gravidez , Estudos Retrospectivos , Medição de Risco , Ultrassonografia
6.
Clin Radiol ; 65(9): 685-94, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20696295

RESUMO

Many types of cardiac and pericardial calcifications identified on chest radiographs can be recognized and distinguished based on characteristic locations and appearances. The purpose of this review is to emphasize the importance of detecting cardiac and pericardial calcifications on chest radiographs, and to illustrate and describe the various types of calcifications that may be encountered and how they may be differentiated from one another. Each type of cardiac and pericardial calcification is discussed, its location and appearance described, and its significance explained. Recognizing and understanding these calcifications is important as they are often encountered in daily practice and play an important role in patient care.


Assuntos
Calcinose/diagnóstico por imagem , Cardiomiopatias/diagnóstico por imagem , Aneurisma Coronário/diagnóstico por imagem , Coração/diagnóstico por imagem , Radiografia Torácica/métodos , Cardiomiopatias/fisiopatologia , Aneurisma Coronário/fisiopatologia , Diagnóstico Diferencial , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Humanos
7.
Antimicrob Agents Chemother ; 48(9): 3323-31, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15328092

RESUMO

This randomized, double-blind, noninferiority trial was designed to demonstrate that pharmacokinetically enhanced amoxicillin-clavulanate (2,000/125 mg) was at least as effective clinically as amoxicillin-clavulanate 875/125 mg, both given twice daily for 7 days, in the treatment of community-acquired pneumonia in adults. In total, 633 clinically and radiologically confirmed community-acquired pneumonia patients (intent-to-treat population) were randomized to receive either oral amoxicillin-clavulanate 2,000/125 mg (n = 322) or oral amoxicillin-clavulanate 875/125 mg (n = 311). At screening, 160 of 633 (25.3%) patients had at least one typical pathogen isolated from expectorated or invasive sputum samples or blood culture (bacteriology intent-to-treat population). Streptococcus pneumoniae (58 of 160, 36.3%), methicillin-susceptible Staphylococcus aureus (34 of 160, 21.3%), and Haemophilus influenzae (33 of 160, 20.6%) were the most common typical causative pathogens isolated in both groups in the bacteriology intent-to-treat population. Clinical success in the clinical per protocol population at test of cure (days 16 to 37), the primary efficacy endpoint, was 90.3% (223 of 247) for amoxicillin-clavulanate 2,000/125 mg and 87.6% (198 of 226) for amoxicillin-clavulanate 875/125 mg (treatment difference, 2.7; 95% confidence interval, -3.0, 8.3). Bacteriological success at test of cure in the bacteriology per protocol population was 86.6% (58 of 67) for amoxicillin-clavulanate 2,000/125 mg and 78.4% (40 of 51) for amoxicillin-clavulanate 875/125 mg (treatment difference, 8.1%; 95% confidence interval, -5.8, 22.1). Both therapies were well tolerated. Amoxicillin-clavulanate 2,000/125 mg twice daily was shown to be as clinically effective as amoxicillin-clavulanate 875/125 mg twice daily for 7 days in the treatment of adult patients with community-acquired pneumonia, without a noted increase in the reported rate of adverse events.


Assuntos
Combinação Amoxicilina e Clavulanato de Potássio/uso terapêutico , Infecções Comunitárias Adquiridas/tratamento farmacológico , Quimioterapia Combinada/uso terapêutico , Pneumonia/tratamento farmacológico , Adolescente , Adulto , Idoso , Combinação Amoxicilina e Clavulanato de Potássio/efeitos adversos , Combinação Amoxicilina e Clavulanato de Potássio/farmacocinética , Química Farmacêutica , Infecções Comunitárias Adquiridas/microbiologia , Método Duplo-Cego , Quimioterapia Combinada/efeitos adversos , Quimioterapia Combinada/farmacocinética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia/microbiologia , Escarro/microbiologia , Streptococcus pneumoniae/efeitos dos fármacos , Resultado do Tratamento
8.
Clin Infect Dis ; 35(4): 428-33, 2002 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-12145727

RESUMO

An open-label, multicenter study was performed to assess bacteriologic findings associated with chronic bacterial maxillary sinusitis in adults. Seventy aerobic (52.2%) and 64 anaerobic (47.8%) pathogens were recovered from clinically evaluable patients at baseline (before therapy). The most commonly isolated anaerobes were Prevotella species (31.1%), anaerobic streptococci (21.9%), and Fusobacterium species (15.6%). The aerobes most frequently recovered included Streptococcus species (21.4%), Haemophilus influenzae (15.7%), Pseudomonas aeruginosa (15.7%), and Staphylococcus aureus and Moraxella catarrhalis (10.0% each). Recurrences of signs or symptoms of bacterial maxillary sinusitis associated with anaerobes were twice as frequent as were those associated with aerobes when counts of anaerobes were > or =10(3) cfu/mL. A pathogenic role for Granulicatella species in cases of chronic sinusitis was documented for the first time.


Assuntos
Bactérias Aeróbias , Bactérias Anaeróbias , Sinusite Maxilar/microbiologia , Adulto , Combinação Amoxicilina e Clavulanato de Potássio/uso terapêutico , Bactérias Aeróbias/efeitos dos fármacos , Bactérias Anaeróbias/efeitos dos fármacos , Doença Crônica , Farmacorresistência Bacteriana , Quimioterapia Combinada/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Humanos , Testes de Sensibilidade Microbiana , Penicilina G/farmacologia
10.
Physician Exec ; 27(2): 8-11, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11291227

RESUMO

The Leading Beyond the Bottom Line article series has received an overwhelming response from ACPE members, mostly in enthusiastic support of this new leadership concept. Some of the important questions raised by members are presented with answers from the authors. This article also explores the moral challenge of leadership and why health care is more than a business. In recent years, there's been confusion about the role of the health care enterprise, its leadership and its management. We have lost our way about the "moral" thing, the "right" thing, because we have no philosophy to guide us. To manage or lead in this "business" of health care, a philosophy is required that recognizes the multiple elements to which the leader has responsibility and obligations: the customers, community, employees, and, certainly, the financial assets.


Assuntos
Atenção à Saúde/organização & administração , Liderança , Cultura Organizacional , Diretores Médicos , Relações Comunidade-Instituição , Atenção à Saúde/normas , Ética Profissional , Humanos , Princípios Morais , Relações Médico-Paciente , Estados Unidos
13.
Physician Exec ; 26(6): 6-9, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11187410

RESUMO

Organizations are created to aggregate resources to accomplish some purpose, be it to provide health care, raise a family, or build cars. These resources are assets. A manager has a fiduciary responsibility, by practice, and, in many cases, by law, to make the best use of those assets. Traditionally, we've evaluated the use of assets through financial statements. The troublesome aspect of these financial statements is that they were designed to measure only those things that can be counted simply--financial and physical assets. But our world has moved from an industrial, manufacturing age to an information, service economy and we are learning that intangible assets are as powerful--potentially more powerful--in creating value as are tangible assets. Recognizing the intangible asset value of employees, customers, and the community is the challenge in this new service economy. Effective health care leaders need to leverage and manage all of an organization's assets.


Assuntos
Atenção à Saúde/organização & administração , Liderança , Diretores Médicos , Comportamento do Consumidor , Cultura Organizacional , Gestão de Recursos Humanos , Estados Unidos
14.
Cancer Res ; 60(24): 7008-13, 2000 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11156404

RESUMO

A persistent question in the field of antibody imaging and therapy is whether increased affinity is advantageous for the targeting of tumors. We have addressed this issue by using a manipulatable model system to investigate the impact of affinity and antigen density on antibody localization. In vitro enzyme-linked immunosorbent assays and bead-binding assays were carried out using BSA conjugated with high and low densities (HD and LD, respectively) of the chemical hapten rho-azophenyl-arsonate as an antigen. Isotype-matched monoclonal antibodies (mAbs) 36-65 and 36-71, with identical epitope specificity but 200-fold differences in affinity, were chosen as targeting agents. The relative in vitro binding of 36-65 and 36-71 was compared with an artificial "tumor" model in vivo using antigen-substituted beads s.c. implanted into SCID mice. Nonsubstituted BSA beads were implanted in the contralateral groin as a nonspecific control. The efficacy of the targeting of [125I]-labeled antibodies was assessed by the imaging of animals on a gamma-scintillation camera using quantitative region-of-interest image analysis over the course of 2 weeks and by postmortem tissue counting. In vitro, both antibodies bound well to the HD antigen, whereas only the high-affinity mAb 36-71 bound effectively to the LD antigen. In vivo, high-affinity mAb 36-71 bound appreciably to both LD and HD beads. In contrast, there was no specific localization of low-affinity mAb 36-65 to LD antigen beads, although the antibody did bind to the beads with the HD antigen. Whereas the high-affinity mAb 36-71 increased its binding to HD beads throughout the 14 days of observation, binding of the high affinity antibody to LD beads and of the low affinity antibody to HD beads plateaued between 10-14 days. These in vitro and in vivo findings demonstrate that the need for a high-affinity antibody is dependent on the density of the target antigen. High-affinity antibodies bind effectively even with a single antigen-Fab interaction, irrespective of the antigen density. In contrast, low-affinity antibodies, because of weak individual antigen-Fab interactions, require the avidity conferred by divalent binding for effective attachment, which can only occur if antigen density is above a certain threshold. An understanding of the differential behavior of high- and low-affinity antibodies and the impact of avidity is useful in predicting the binding of monovalent antibody fragments and engineered antibody constructs and underlies the trend toward development of multivalent immunological moieties. Consideration of the relative density of the antigen on the tumor and the background tissues may enable and even favor targeting with low-affinity antibodies in selected situations.


Assuntos
Afinidade de Anticorpos , Antígenos/metabolismo , Animais , Cromatografia de Afinidade , Relação Dose-Resposta Imunológica , Ensaio de Imunoadsorção Enzimática , Raios gama , Imunoglobulina G/imunologia , Imunoglobulinas/metabolismo , Camundongos , Camundongos SCID , Modelos Biológicos , Fatores de Tempo
15.
J Med Pract Manage ; 14(4): 172-6, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10623408

RESUMO

The increasingly competitive environment of practice management has become more complicated with the growing penetration of managed care and capitation. Although successful growing practices have always focused on attracting new patients into the office, future efforts must also be directed at retaining the current patient. Additionally, capitation will require that a practice redefine the profile of a patient valuable to the practice. This article provides a perspective on the valuable patient in a capitated setting as well as some strategies to build better relationships with patients to retain their loyalty. Finally, this article proposes a system to monitor the ongoing satisfaction of patients to retain loyalty.


Assuntos
Programas de Assistência Gerenciada/organização & administração , Satisfação do Paciente , Assistência Centrada no Paciente/organização & administração , Administração da Prática Médica/organização & administração , Humanos , Marketing de Serviços de Saúde , Relações Médico-Paciente , Estados Unidos
17.
Physician Exec ; 23(8): 46-51, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-10176687

RESUMO

Why is strategic positioning so important to health care organizations struggling in a managed care environment and what are the sources of value? In Part 1 of this article, entitled "The Sources of Value under Managed Care," the authors presented four sources of value relative to the evolution of the market from fee-for-service to managed care. These value sources are: (1) assets, (2) price/performance, (3) distribution, and, ultimately, (4) capabilities and brand equity. In this article, the authors further elaborate on the sources of value as the market moves beyond the historical fee-for-service position to a managed care marketplace. Part 2 presents the marketing and financial challenges to organizational positioning and performance across the four stages of managed care.


Assuntos
Prestação Integrada de Cuidados de Saúde/organização & administração , Programas de Assistência Gerenciada/organização & administração , Marketing de Serviços de Saúde , Técnicas de Planejamento , Prestação Integrada de Cuidados de Saúde/economia , Competição Econômica/organização & administração , Estudos de Avaliação como Assunto , Setor de Assistência à Saúde/tendências , Planejamento Hospitalar/economia , Planejamento Hospitalar/organização & administração , Programas de Assistência Gerenciada/economia , Modelos Organizacionais , Objetivos Organizacionais , Avaliação de Programas e Projetos de Saúde , Estados Unidos
18.
Physician Exec ; 23(6): 6-12, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-10169353

RESUMO

Part 1 of this series organizes and discusses the sources of value against a background of an evolving managed care market. Part 2 will present, in more detail, the marketing and financial challenges to organizational positioning and performance across the four stages of managed care. What are the basic principles or tenets of value and how do they apply to the health care industry? Why is strategic positioning so important to health care organizations struggling in a managed care environment and what are the sources of value? Service motivated employees and the systems that educate them represent a stronger competitive advantage than having assets and technology that are available to anyone. As the health care marketplace evolves, organizations must develop a strategic position that will provide such value and for which the customer will be willing to pay.


Assuntos
Participação da Comunidade/economia , Competição Econômica , Programas de Assistência Gerenciada/economia , Marketing de Serviços de Saúde/normas , Análise Custo-Benefício , Prestação Integrada de Cuidados de Saúde/economia , Prestação Integrada de Cuidados de Saúde/organização & administração , Indicadores Básicos de Saúde , Programas de Assistência Gerenciada/organização & administração , Competição em Planos de Saúde , Motivação , Técnicas de Planejamento , Valores Sociais , Estados Unidos
20.
Oncogene ; 14(18): 2229-38, 1997 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-9174059

RESUMO

DNase I footprinting of the rat TGF alpha promoter in the presence of crude cell nuclear extract revealed three sites of protein-DNA interaction (Fp-A, Fp-B, Fp-C) in the region from -222 to +73. Mutation of specific sites within the Fp-A and Fp-B regions reduced expression of a TGF alpha promoter-reporter gene (TGF alphaLUC) from 50-90% in transiently transfected CHO cells, indicating the importance of protein/DNA interactions at these sites. Since Fp-A contained a perfect AP2 consensus sequence (5'-GCCNNNGGC-3') as its center, we investigated the possibility that AP2 binding is important for TGF alpha promoter activity. A double-stranded oligonucleotide spanning Fp-A displayed a distinct mobility shift in the presence of nuclear extract that was inhibited by an excess of known functional AP2-binding sequence. Moreover, a similar mobility shift occurred in the presence of purified AP2 protein, and the further addition of AP2 antibody produced a supershifted complex. More refined DNase I footprinting of a smaller, oligonucleotide probe in the presence of purified AP2 protein revealed a protected region that included the putative AP2 binding site. Additionally, co-transfection of an AP2 expression vector increased TGF alphaLUC expression 25-fold in Drosophila Schneider cells. These various findings corroborate a role for AP2 in TGF alpha promoter activity. The Fp-B region contains a T5 motif that has been previously suggested to function as an atypical TATA box. An Fp-B oligonucleotide displayed a specific gel mobility shift in the presence of a TATA binding protein (TBP)-TFIIA complex, and the further addition of TBP antibody produced a supershift. These results confirm that protein binding within Fp-B is functionally important, and they also indicate that the T5 motif functions as a TBP binding site.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador alfa/genética , Fator de Crescimento Transformador alfa/metabolismo , Animais , Sequência de Bases , Sítios de Ligação , Células CHO/metabolismo , Linhagem Celular , Linhagem Celular Transformada , Cricetinae , Pegada de DNA , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila , Eletroforese/métodos , Células Epiteliais , Regulação da Expressão Gênica , Fígado/citologia , Dados de Sequência Molecular , Mutação , Regiões Promotoras Genéticas , Ratos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteína de Ligação a TATA-Box , Fator de Transcrição AP-2 , Fator de Transcrição TFIIA
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