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1.
Am J Perinatol ; 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714204

RESUMO

OBJECTIVE: Fetal fibronectin (fFN) testing and transvaginal ultrasound (TVUS) are diagnostic tools used to predict impending spontaneous preterm birth (sPTB) among women presenting with preterm labor (PTL). We evaluated the association between fFN testing or TVUS cervical length (CL) measurement in predicting sPTB, respiratory distress syndrome (RDS), neonatal intensive care unit (NICU) admission, and sPTB-related costs. STUDY DESIGN: We conducted a retrospective cohort study using data from the Kaiser Permanente Southern California electronic health system (January 1, 2009-December 31, 2020) using diagnostic and procedure codes, along with a natural language processing algorithm to identify pregnancies with PTL evaluations. PTL evaluation was defined as having fFN and/or TVUS assessment. Outcomes were ascertained using diagnostic, procedural, and diagnosis-related group codes. Multivariable logistic regression assessed the association between fFN and/or TVUS results and perinatal outcomes. RESULTS: Compared with those without PTL evaluations, those with positive fFN tests had higher adjusted odds ratio (adj.OR) for sPTB (2.95, 95% confidence interval [CI]: 2.64, 3.29), RDS (2.34, 95% CI: 2.03, 2.69), and NICU admission (2.24, 95% CI: 2.01, 2.50). In contrast, those who tested negative had lower odds for sPTB (adj.OR: 0.75, 95% CI: 0.70, 0.79), RDS (adj.OR: 0.67, 95% CI: 0.61, 0.73), and NICU admission (adj.OR: 0.74, 95% CI: 0.70, 0.79). Among those with positive fFN results, the odds of sPTB was inversely associated with CL. Health care costs for mothers and neonates were lowest for those with fFN testing only. CONCLUSION: This study demonstrates that positive fFN results were associated with an increased odds of sPTB, RDS, and NICU admission and the association with sPTB was inversely proportional to CL. Additionally, negative fFN results were associated with decreased odds of sPTB, RDS, and NICU admissions. fFN testing may predict these and other sPTB-related adverse outcomes hence its utility should be explored further. Moreover, fFN testing has some cost savings over TVUS. KEY POINTS: · Patients with positive fFN tests had higher odds of sPTB, RDS, and NICU admission.. · Inverse relationship between sPTB and CL among those with positive fFN tests was observed.. · Health care costs for mothers and neonates were lowest for those with fFN testing only..

2.
Nature ; 489(7415): 304-8, 2012 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-22972301

RESUMO

Embryonic stem cells can replicate continuously in the absence of senescence and, therefore, are immortal in culture. Although genome stability is essential for the survival of stem cells, proteome stability may have an equally important role in stem-cell identity and function. Furthermore, with the asymmetric divisions invoked by stem cells, the passage of damaged proteins to daughter cells could potentially destroy the resulting lineage of cells. Therefore, a firm understanding of how stem cells maintain their proteome is of central importance. Here we show that human embryonic stem cells (hESCs) exhibit high proteasome activity that is correlated with increased levels of the 19S proteasome subunit PSMD11 (known as RPN-6 in Caenorhabditis elegans) and a corresponding increased assembly of the 26S/30S proteasome. Ectopic expression of PSMD11 is sufficient to increase proteasome assembly and activity. FOXO4, an insulin/insulin-like growth factor-I (IGF-I) responsive transcription factor associated with long lifespan in invertebrates, regulates proteasome activity by modulating the expression of PSMD11 in hESCs. Proteasome inhibition in hESCs affects the expression of pluripotency markers and the levels of specific markers of the distinct germ layers. Our results suggest a new regulation of proteostasis in hESCs that links longevity and stress resistance in invertebrates to hESC function and identity.


Assuntos
Células-Tronco Embrionárias/enzimologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas de Ciclo Celular , Diferenciação Celular , Linhagem Celular , Células-Tronco Embrionárias/efeitos dos fármacos , Células-Tronco Embrionárias/metabolismo , Fatores de Transcrição Forkhead , Células HEK293 , Humanos , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Inibidores de Proteassoma , Subunidades Proteicas/metabolismo , Fatores de Transcrição/metabolismo , Regulação para Cima
3.
Aging Cell ; 11(3): 491-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22360389

RESUMO

Reducing the activity of the insulin/IGF-1 signaling pathway (IIS) modifies development, elevates stress resistance, protects from toxic protein aggregation (proteotoxicity), and extends lifespan (LS) of worms, flies, and mice. In the nematode Caenorhabditis elegans, LS extension by IIS reduction is entirely dependent upon the activity of the transcription factors DAF-16 and the heat shock factor-1 (HSF-1). While DAF-16 determines LS exclusively during early adulthood, it is required for proteotoxicity protection also during late adulthood. In contrast, HSF-1 protects from proteotoxicity during larval development. Despite the critical requirement for HSF-1 for LS extension, the temporal requirements for this transcription factor as a LS determinant are unknown. To establish the temporal requirements of HSF-1 for longevity assurance, we conditionally knocked down hsf-1 during larval development and adulthood of C. elegans and found that unlike daf-16, hsf-1 is foremost required for LS determination during early larval development, required for a lesser extent during early adulthood and has small effect on longevity also during late adulthood. Our findings indicate that early developmental events affect LS and suggest that HSF-1 sets during development of the conditions that enable DAF-16 to promote longevity during reproductive adulthood. This study proposes a novel link between HSF-1 and the longevity functions of the IIS.


Assuntos
Proteínas de Caenorhabditis elegans/fisiologia , Longevidade/fisiologia , Fatores de Transcrição/fisiologia , Animais , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/biossíntese , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Senescência Celular/fisiologia , Fatores de Transcrição Forkhead , Técnicas de Silenciamento de Genes , Insulina/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Interferência de RNA , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Transdução de Sinais , Fatores de Transcrição/biossíntese , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
4.
Aging Cell ; 9(2): 126-34, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20003171

RESUMO

Toxic protein aggregation (proteotoxicity) is a unifying feature in the development of late-onset human neurodegenerative disorders. Reduction of insulin/IGF-1 signaling (IIS), a prominent lifespan, developmental and reproductive regulatory pathway, protects worms from proteotoxicity associated with the aggregation of the Alzheimer's disease-linked Abeta peptide. We utilized transgenic nematodes that express human Abeta and found that late life IIS reduction efficiently protects from Abeta toxicity without affecting development, reproduction or lifespan. To alleviate proteotoxic stress in the animal, the IIS requires heat shock factor (HSF)-1 to modulate a protein disaggregase, while DAF-16 regulates a presumptive active aggregase, raising the question of how these opposing activities could be co-regulated. One possibility is that HSF-1 and DAF-16 have distinct temporal requirements for protection from proteotoxicity. Using a conditional RNAi approach, we found an early requirement for HSF-1 that is distinct from the adult functions of DAF-16 for protection from proteotoxicity. Our data also indicate that late life IIS reduction can protect from proteotoxicity when it can no longer promote longevity, strengthening the prospect that IIS reduction might be a promising strategy for the treatment of neurodegenerative disorders caused by proteotoxicity.


Assuntos
Caenorhabditis elegans/metabolismo , Transdução de Sinais , Transporte Ativo do Núcleo Celular , Peptídeos beta-Amiloides/metabolismo , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/crescimento & desenvolvimento , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Senescência Celular , Fatores de Transcrição Forkhead , Insulina/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Larva/crescimento & desenvolvimento , Larva/metabolismo , Fragmentos de Peptídeos/metabolismo , Interferência de RNA , Receptor de Insulina/genética , Receptor de Insulina/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
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