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1.
Breast Cancer Res ; 22(1): 104, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33004039

RESUMO

BACKGROUND: Systemic inflammation may play a role in shaping breast composition, one of the strongest risk factors for breast cancer. Pubertal development presents a critical window of breast tissue susceptibility to exogenous and endogenous factors, including pro-inflammatory markers. However, little is known about the role of systemic inflammation on adolescent breast composition and pubertal development among girls. METHODS: We investigated associations between circulating levels of inflammatory markers (e.g., interleukin-6 (IL-6), tumor necrosis factor receptor 2 (TNFR2), and C-reactive protein (CRP)) at Tanner stages 2 and 4 and breast composition at Tanner stage 4 in a cohort of 397 adolescent girls in Santiago, Chile (Growth and Obesity Cohort Study, 2006-2018). Multivariable linear models were used to examine the association between breast composition and each inflammatory marker, stratifying by Tanner stage at inflammatory marker measurement. Accelerated failure time models were used to evaluate the association between inflammatory markers concentrations at each Tanner stage and time to menarche. RESULTS: In age-adjusted linear regression models, a doubling of TNFR2 at Tanner 2 was associated with a 26% (95% CI 7-48%) increase in total breast volume at Tanner 4 and a 22% (95% CI 10-32%) decrease of fibroglandular volume at Tanner 4. In multivariable models further adjusted for body fatness and other covariates, these associations were attenuated to the null. The time to menarche was 3% (95% CI 1-5%) shorter among those in the highest quartile of IL-6 at Tanner 2 relative to those in the lowest quartile in fully adjusted models. Compared to those in the lowest quartile of CRP at Tanner 4, those in the highest quartile experienced 2% (95% CI 0-3%) longer time to menarche in multivariable models. CONCLUSIONS: Systemic inflammation during puberty was not associated with breast volume or breast density at the conclusion of breast development among pubertal girls after adjusting for body fatness; however, these circulating inflammation biomarkers, specifically CRP and IL-6, may affect the timing of menarche onset.


Assuntos
Biomarcadores/sangue , Densidade da Mama , Mama/imunologia , Inflamação/imunologia , Menarca , Puberdade , Mama/crescimento & desenvolvimento , Mama/metabolismo , Proteína C-Reativa/metabolismo , Criança , Estudos de Coortes , Feminino , Humanos , Inflamação/metabolismo , Interleucina-6/metabolismo , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo , Fatores de Risco , Maturidade Sexual
2.
BMC Genomics ; 18(1): 533, 2017 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-28716048

RESUMO

BACKGROUND: The ubiquitin 26S proteasome system (UPS) selectively degrades cellular proteins, which results in physiological changes to eukaryotic cells. F-box proteins are substrate adaptors within the UPS and are responsible for the diversity of potential protein targets. Plant genomes are enriched in F-box genes, but the vast majority of these have unknown roles. This work investigated the Arabidopsis F-box gene F-BOX STRESS INDUCED 1 (FBS1) for its effects on gene expression in order elucidate its previously unknown biological function. RESULTS: Using publically available Affymetrix ATH1 microarray data, we show that FBS1 is significantly co-expressed in abiotic stresses with other well-characterized stress response genes, including important stress-related transcriptional regulators. This gene suite is most highly expressed in roots under cold and salt stresses. Transcriptome analysis of fbs1-1 knock-out plants grown at a chilling temperature shows that hundreds of genes require FBS1 for appropriate expression, and that these genes are enriched in those having roles in both abiotic and biotic stress responses. Based on both this genome-wide expression data set and quantitative real-time PCR (qPCR) analysis, it is apparent that FBS1 is required for elevated expression of many jasmonic acid (JA) genes that have established roles in combatting environmental stresses, and that it also controls a subset of JA biosynthesis genes. FBS1 also significantly impacts abscisic acid (ABA) regulated genes, but this interaction is more complex, as FBS1 has both positive and negative effects on ABA-inducible and ABA-repressible gene modules. One noteworthy effect of FBS1 on ABA-related stress processes, however, is the restraint it imposes on the expression of multiple class I LIPID TRANSFER PROTEIN (LTP) gene family members that have demonstrated protective effects in water deficit-related stresses. CONCLUSION: FBS1 impacts plant stress responses by regulating hundreds of genes that respond to the plant stress hormones JA and ABA. The positive effect that FBS1 has on JA processes and the negative effect it has on at least some ABA processes indicates that it in part regulates cellular responses balanced between these two important stress hormones. More broadly then, FBS1 may aid plant cells in switching between certain biotic (JA) and abiotic (ABA) stress responses. Finally, because FBS1 regulates a subset of JA biosynthesis and response genes, we conclude that it might have a role in tuning hormone responses to particular circumstances at the transcriptional level.


Assuntos
Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/genética , Arabidopsis/genética , Arabidopsis/fisiologia , Ciclopentanos/metabolismo , Perfilação da Expressão Gênica , Proteínas de Choque Térmico/genética , Oxilipinas/metabolismo , Estresse Fisiológico/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Temperatura Baixa , Proteínas de Choque Térmico/metabolismo
3.
Langmuir ; 28(8): 3807-13, 2012 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-22272555

RESUMO

Surfaces grafted with poly(methyl methacrylate) (PMMA) and streptavidin were synthesized through click chemistry to investigate the role of surface stiffness on protein adsorption as the hydrophilic and hydrophobic surface coverage of the substituents vary. Surface topographies coupled with the nanoindentation results indicated that, with the appropriate selections of polymer coverage and chain length, the extent of non-specific protein adhesion could be controlled by the hydrophobic interactions between PMMA, biotin, and streptavidin. It was shown that, when the molecular weight and stiffness of PMMA was close to that of streptavidin, patchy PMMA morphologies were obtained, which help inhibit the non-specific adsorption of streptavidin.


Assuntos
Polímeros/química , Proteínas/química , Elasticidade , Polimetil Metacrilato/química , Estreptavidina/química , Propriedades de Superfície
4.
Amyotroph Lateral Scler ; 9(1): 50-8, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18270879

RESUMO

R+ pramipexole (PPX) is a lipophilic cation that concentrates into brain and mitochondria and efficiently scavenges reactive oxygen and nitrogen species (RONS). Under the auspices of a Physician-Sponsor IND, R+PPX was dosed to small numbers of ALS patients for tolerability and safety while efficacy measures were also collected. The purpose of this paper is to describe the outcomes of these initial clinical studies. In a futility design study, 30 patients with early SALS were evaluated monthly for ALSFRS-R scores and FVC measurements for three months during lead-in, followed by open-label dosing at 30 mg/day of R+PPX for the next six months. In the dose escalation study, 10 subjects with early ALS received daily doses of R+PPX from 10 mg t.i.d. to 100 mg t.i.d. over seven weeks. In the open-label extension analysis, subjects from the initial studies were treated with 30 mg/day for at least six months, then switched to 60 mg/day. R+PPX was tolerated well in all studies. In the futility study, slopes of decline in ALSFRS-R scores and neurophysiological index (NI) values yielded non-significant reductions during treatment. In the dose-escalation study, all subjects increased daily R+PPX intake safely to 100 mg t.i.d. Markers of ALS did not change (ALSFRS-R) or improved (FVC). Trough and peak plasma (PPX) increased linearly with dosing, and several subjects achieved plasma (PPX) >1 microM. In the open-label extension protocol, changing from 30 to 60 mg/day caused a non-significant 17% reduction in slope of decline of ALSFRS-R. It was concluded that R+PPX was tolerated well in long-term dosing at 30 and 60 mg/day. Encouraging but non-significant effects of R+PPX on ALS decline were observed. High doses of R+PPX were tolerated well and yielded neuroprotective plasma levels. These findings support longer-term testing of higher R+PPX doses as a potential disease-altering therapy for SALS.


Assuntos
Esclerose Lateral Amiotrófica/tratamento farmacológico , Benzotiazóis/metabolismo , Benzotiazóis/uso terapêutico , Mitocôndrias/efeitos dos fármacos , Fármacos Neuroprotetores/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Adulto , Idoso , Esclerose Lateral Amiotrófica/patologia , Benzotiazóis/farmacologia , Relação Dose-Resposta a Droga , Feminino , Sequestradores de Radicais Livres/metabolismo , Sequestradores de Radicais Livres/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Fármacos Neuroprotetores/farmacologia , Pramipexol , Fatores de Tempo
5.
Clin Epigenetics ; 10(1): 122, 2018 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-30286806

RESUMO

BACKGROUND: Estrogen receptor-α (ER-α) is a transcriptional regulator, which mediates estrogen-dependent breast development, as well as breast tumorigenesis. The influence of epigenetic regulation of ER-α on adolescent breast composition has not been previously studied and could serve as a marker of pubertal health and susceptibility to breast cancer. We investigated the association between ER-α DNA methylation in leukocytes and breast composition in adolescent Chilean girls enrolled in the Growth and Obesity Cohort Study (GOCS) in Santiago, Chile. Breast composition (total breast volume (BV; cm3), fibroglandular volume (FGV; cm3), and percent fibroglandular volume (%FGV)) was measured at breast Tanner stage 4 (B4). ER-α promoter DNA methylation was assessed by pyrosequencing in blood samples collected at breast Tanner stages 2 (B2; n = 256) and B4 (n = 338). RESULTS: After adjusting for fat percentage at breast density measurement, ER-α methylation at B2, and cellular heterogeneity, we observed an inverse association between B4 average ER-α DNA methylation and BV and FGV. Geometric mean BV was 15% lower (95% CI: - 28%, - 1%) among girls in the highest quartile of B4 ER-α methylation (6.96-23.60%) relative to the lowest (0.78-3.37%). Similarly, FGV was 19% lower (95% CI: - 33%, - 2%) among girls in the highest quartile of B4 ER-α methylation relative to the lowest. The association between ER-α methylation and breast composition was not significantly modified by body fat percentage and was not influenced by pubertal timing. CONCLUSIONS: These findings suggest that the methylation profile of ER-α may modulate adolescent response to estrogen and breast composition, which may influence breast cancer risk in adulthood.


Assuntos
Mama/química , Metilação de DNA , Receptor alfa de Estrogênio/genética , Análise de Sequência de DNA/métodos , Adolescente , Densidade da Mama , Chile , Estudos de Coortes , Epigênese Genética , Feminino , Humanos , Regiões Promotoras Genéticas
6.
Bioorg Med Chem Lett ; 14(11): 2973-7, 2004 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-15125971

RESUMO

N-Aryl aminothiazoles 6-9 were prepared from 2-bromothiazole 5 and found to be CDK inhibitors. In cells they act as potent cytotoxic agents. Selectivity for CDK1, CDK2, and CDK4 was dependent of the nature of the N-aryl group and distinct from the CDK2 selective N-acyl analogues. The N-2-pyridyl analogues 7 and 19 showed pan CDK inhibitory activity. Elaborated analogues 19 and 23 exhibited anticancer activity in mice against P388 murine leukemia. The solid-state structure of 7 bound to CDK2 shows a similar binding mode to the N-acyl analogues.


Assuntos
Antineoplásicos/síntese química , Quinases Ciclina-Dependentes/antagonistas & inibidores , Tiazóis/farmacologia , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Concentração Inibidora 50 , Leucemia/tratamento farmacológico , Camundongos , Neoplasias Experimentais/tratamento farmacológico , Ligação Proteica , Relação Estrutura-Atividade , Tiazóis/síntese química , Resultado do Tratamento
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