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1.
Proc Natl Acad Sci U S A ; 121(10): e2315860121, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38408244

RESUMO

Human cytomegalovirus (HCMV) is a prevalent pathogen that establishes life-long latent infection in hematopoietic cells. While this infection is usually asymptomatic, immune dysregulation leads to viral reactivation, which can cause significant morbidity and mortality. However, the mechanisms underpinning reactivation remain incompletely understood. The HCMV major immediate early promoter (MIEP)/enhancer is a key factor in this process, as its transactivation from a repressed to active state helps drive viral gene transcription necessary for reactivation from latency. Numerous host transcription factors bind the MIE locus and recruit repressive chromatin modifiers, thus impeding virus reactivation. One such factor is CCCTC-binding protein (CTCF), a highly conserved host zinc finger protein that mediates chromatin conformation and nuclear architecture. However, the mechanisms by which CTCF contributes to HCMV latency were previously unexplored. Here, we confirm that CTCF binds two convergent sites within the MIE locus during latency in primary CD14+ monocytes, and following cellular differentiation, CTCF association is lost as the virus reactivates. While mutation of the MIE enhancer CTCF binding site does not impact viral lytic growth in fibroblasts, this mutant virus fails to maintain latency in myeloid cells. Furthermore, we show the two convergent CTCF binding sites allow looping to occur across the MIEP, supporting transcriptional repression during latency. Indeed, looping between the two sites diminishes during virus reactivation, concurrent with activation of MIE transcription. Taken together, our data reveal that three-dimensional chromatin looping aids in the regulation of HCMV latency and provides insight into promoter/enhancer regulation that may prove broadly applicable across biological systems.


Assuntos
Infecções por Citomegalovirus , Citomegalovirus , Humanos , Cromatina/genética , Citomegalovirus/genética , Infecções por Citomegalovirus/genética , Regulação Viral da Expressão Gênica , Regiões Promotoras Genéticas , Ativação Viral/genética , Latência Viral/genética
2.
EMBO J ; 41(8): e109700, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35274759

RESUMO

HOIL-1, a component of the linear ubiquitin chain assembly complex (LUBAC), ubiquitylates serine and threonine residues in proteins by esterification. Here, we report that mice expressing an E3 ligase-inactive HOIL-1[C458S] mutant accumulate polyglucosan in brain, heart and other organs, indicating that HOIL-1's E3 ligase activity is essential to prevent these toxic polysaccharide deposits from accumulating. We found that HOIL-1 monoubiquitylates glycogen and α1:4-linked maltoheptaose in vitro and identify the C6 hydroxyl moiety of glucose as the site of ester-linked ubiquitylation. The monoubiquitylation of maltoheptaose was accelerated > 100-fold by the interaction of Met1-linked or Lys63-linked ubiquitin oligomers with the RBR domain of HOIL-1. HOIL-1 also transferred pre-formed ubiquitin oligomers to maltoheptaose en bloc, producing polyubiquitylated maltoheptaose in one catalytic step. The Sharpin and HOIP components of LUBAC, but not HOIL-1, bound to unbranched and infrequently branched glucose polymers in vitro, but not to highly branched mammalian glycogen, suggesting a potential function in targeting HOIL-1 to unbranched glucosaccharides in cells. We suggest that monoubiquitylation of unbranched glucosaccharides may initiate their removal from cells, preventing precipitation as polyglucosan.


Assuntos
Ubiquitina-Proteína Ligases , Ubiquitina , Animais , Glucanos , Glucose , Glicogênio/metabolismo , Mamíferos , Camundongos , NF-kappa B/metabolismo , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
3.
EMBO J ; 41(21): e111015, 2022 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-36121123

RESUMO

Protein UFMylation, i.e., post-translational modification with ubiquitin-fold modifier 1 (UFM1), is essential for cellular and endoplasmic reticulum homeostasis. Despite its biological importance, we have a poor understanding of how UFM1 is conjugated onto substrates. Here, we use a rebuilding approach to define the minimal requirements of protein UFMylation. We find that the reported cognate E3 ligase UFL1 is inactive on its own and instead requires the adaptor protein UFBP1 to form an active E3 ligase complex. Structure predictions suggest the UFL1/UFBP1 complex to be made up of winged helix (WH) domain repeats. We show that UFL1/UFBP1 utilizes a scaffold-type E3 ligase mechanism that activates the UFM1-conjugating E2 enzyme, UFC1, for aminolysis. Further, we characterize a second adaptor protein CDK5RAP3 that binds to and forms an integral part of the ligase complex. Unexpectedly, we find that CDK5RAP3 inhibits UFL1/UFBP1 ligase activity in vitro. Results from reconstituting ribosome UFMylation suggest that CDK5RAP3 functions as a substrate adaptor that directs UFMylation to the ribosomal protein RPL26. In summary, our reconstitution approach reveals the biochemical basis of UFMylation and regulatory principles of this atypical E3 ligase complex.


Assuntos
Retículo Endoplasmático , Ubiquitina-Proteína Ligases , Ubiquitina-Proteína Ligases/metabolismo , Retículo Endoplasmático/metabolismo , Processamento de Proteína Pós-Traducional , Estresse do Retículo Endoplasmático/fisiologia , Ligação Proteica , Proteínas Ribossômicas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo
4.
Mol Cell ; 70(1): 150-164.e6, 2018 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-29576527

RESUMO

Deubiquitinating enzymes (DUBs) are important regulators of ubiquitin signaling. Here, we report the discovery of deubiquitinating activity in ZUFSP/C6orf113. High-resolution crystal structures of ZUFSP in complex with ubiquitin reveal several distinctive features of ubiquitin recognition and catalysis. Our analyses reveal that ZUFSP is a novel DUB with no homology to any known DUBs, leading us to classify ZUFSP as the seventh DUB family. Intriguingly, the minimal catalytic domain does not cleave polyubiquitin. We identify two ubiquitin binding domains in ZUFSP: a ZHA (ZUFSP helical arm) that binds to the distal ubiquitin and an atypical UBZ domain in ZUFSP that binds to polyubiquitin. Importantly, both domains are essential for ZUFSP to selectively cleave K63-linked polyubiquitin. We show that ZUFSP localizes to DNA lesions, where it plays an important role in genome stability pathways, functioning to prevent spontaneous DNA damage and also promote cellular survival in response to exogenous DNA damage.


Assuntos
Núcleo Celular/enzimologia , Dano ao DNA , Enzimas Desubiquitinantes/metabolismo , Instabilidade Genômica , Poliubiquitina/metabolismo , Sítios de Ligação , Sobrevivência Celular , Enzimas Desubiquitinantes/química , Enzimas Desubiquitinantes/genética , Células HEK293 , Células HeLa , Humanos , Células Jurkat , Lisina , Ligação Proteica , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , Relação Estrutura-Atividade , Especificidade por Substrato , Ubiquitinação
5.
Immunity ; 44(4): 795-806, 2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-27067058

RESUMO

Eosinophils are now recognized as multifunctional leukocytes that provide critical homeostatic signals to maintain other immune cells and aid tissue repair. Paradoxically, eosinophils also express an armory of granule-localized toxins and hydrolases believed to contribute to pathology in inflammatory disease. How eosinophils deliver their supporting functions while avoiding self-inflicted injury is poorly understood. We have demonstrated that cystatin F (CF) is a critical survival factor for eosinophils. Eosinophils from CF null mice had reduced lifespan, reduced granularity, and disturbed granule morphology. In vitro, cysteine protease inhibitors restored granularity, demonstrating that control of cysteine protease activity by CF is critical for normal eosinophil development. CF null mice showed reduced pulmonary pathology in a model of allergic lung inflammation but also reduced ability to combat infection by the nematode Brugia malayi. These data identify CF as a "cytoprotectant" that promotes eosinophil survival and function by ensuring granule integrity. VIDEO ABSTRACT.


Assuntos
Brugia Malayi/imunologia , Sobrevivência Celular/imunologia , Cistatinas/genética , Cistatinas/imunologia , Grânulos Citoplasmáticos/metabolismo , Eosinófilos/imunologia , Filariose/imunologia , Animais , Sobrevivência Celular/genética , Células Cultivadas , Cisteína Proteases/metabolismo , Filariose/parasitologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ovalbumina/imunologia
6.
J Physiol ; 602(9): 2127-2139, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38285002

RESUMO

Maternal stress and glucocorticoid exposure during pregnancy have multigenerational effects on neuroendocrine function and behaviours in offspring. Importantly, effects are transmitted through the paternal lineage. Altered phenotypes are associated with profound differences in transcription and DNA methylation in the brain. In the present study, we hypothesized that maternal prenatal synthetic glucocorticoid (sGC) exposure in the F0 pregnancy will result in differences in miRNA levels in testes germ cells and sperm across multiple generations, and that these changes will associate with modified microRNA (miRNA) profiles and gene expression in the prefrontal cortex (PFC) of subsequent generations. Pregnant guinea-pigs (F0) were treated with multiple courses of the sGC betamethasone (Beta) (1 mg kg-1; gestational days 40, 41, 50, 51, 60 and 61) in late gestation. miRNA levels were assessed in testes germ cells and in F2 PFC using the GeneChip miRNA 4.0 Array and candidate miRNA measured in epididymal sperm by quantitative real-time PCR. Maternal Beta exposure did not alter miRNA levels in germ cells derived from the testes of adult male offspring. However, there were significant differences in the levels of four candidate miRNAs in the sperm of F1 and F2 adult males. There were no changes in miRNA levels in the PFC of juvenile F2 female offspring. The present study has identified that maternal Beta exposure leads to altered miRNA levels in sperm that are apparent for at least two generations. The fact that differences were confined to epididymal sperm suggests that the intergenerational effects of Beta may target the epididymis. KEY POINTS: Paternal glucocorticoid exposure prior to conception leads to profound epigenetic changes in the brain and somatic tissues in offspring, and microRNAs (miRNAs) in sperm may mediate these changes. We show that there were significant differences in the miRNA profile of epididymal sperm in two generations following prenatal glucocorticoid exposure that were not observed in germ cells derived from the testes. The epididymis is a probable target for intergenerational programming. The effects of prenatal glucocorticoid treatment may span multiple generations.


Assuntos
Glucocorticoides , MicroRNAs , Efeitos Tardios da Exposição Pré-Natal , Espermatozoides , Animais , Feminino , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Gravidez , Efeitos Tardios da Exposição Pré-Natal/genética , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Cobaias , Glucocorticoides/farmacologia , Testículo/efeitos dos fármacos , Testículo/metabolismo , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/efeitos dos fármacos , Betametasona/farmacologia , Exposição Materna/efeitos adversos
7.
FASEB J ; 37(4): e22879, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36928999

RESUMO

Approximately 1%-3% of the adult population are treated with synthetic glucocorticoids (sGCs) for a variety of conditions. Studies have demonstrated that adversities experienced by males prior to conception may lead to abnormal neuroendocrine function and behaviors in offspring and that epigenetic factors including microRNA (miRNA) within sperm may be responsible for driving these effects. However, it remains unclear where in the epididymis sperm miRNA changes are occurring. Here, we hypothesized that sGC exposure will alter the miRNA profile of sperm in the epididymis in a region-specific manner. Adult male guinea pigs were exposed to regular drinking water (Ctrl) or water with the sGC dexamethasone (Dex; 3mg/kg) (n = 6/group) every other day for 48 days. Sperms were collected from epididymal seminal fluid in the caput and cauda regions of the epididymis and total RNA was extracted. miRNAs were assessed by miRNA 4.0 microarray; data were processed by TAC 4.0.1 and R. miRNA analysis revealed one miRNA in the caput that was significantly decreased by Dex in sperm. In the cauda, 31 miRNAs were reduced in sperm following Dex-exposure. The findings of this study demonstrate that Dex-exposure influences miRNA profile of sperm in the cauda but not the caput of the epididymis. This suggests that glucocorticoids target the epididymis to modify sperm miRNA and do not modify the miRNA content during spermiation in the testes.


Assuntos
Glucocorticoides , MicroRNAs , Masculino , Cobaias , Animais , Sêmen , Espermatozoides , Fertilização , Epididimo , MicroRNAs/genética
8.
Intern Med J ; 54(2): 290-294, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37449655

RESUMO

BACKGROUND: In the last few decades, the life expectancy of patients with transfusion-dependent thalassaemia (TDT) and sickle cell disease (SCD) has improved significantly, in part because of improved iron chelation. Fertility challenges and pregnancy complications have historically limited reproductive options in this group; however, improved multi-disciplinary care has made infertility a chronic disease complication requiring attention. Despite this, there are very few reports and no Australian data describing fertility and pregnancy outcomes in this population. AIMS: To identify the rate of assisted reproductive technologies (ART) utilisation in our female transfusion-dependent haemoglobinopathy patients and to establish the nature of maternal and neonatal complications in this cohort. METHODS: A 20-year retrospective analysis (1997-2017) at an Australian centre captured data on conception rates, use of assisted reproductive techniques (ART), and pregnancy and neonatal outcomes in female transfusion-dependent haemoglobinopathy patients. RESULTS: Conception was attempted in 14 women (11 TDT and three SCD) during the study period. A total of 28 pregnancies resulting in 25 live births were recorded. ART supported 13 conceptions. A positive association was not identified between elevated mean serum ferritin and ART use; however, all patients with an established diagnosis of hypogonadotropic hypogonadism (HH) required ART. Maternal complications included gestational diabetes mellitus and post-partum haemorrhage. There were no cardiac complications. Two-thirds of women underwent lower segment caesarean section, with prematurity complicating 20% of births. There were no neonatal or maternal deaths. CONCLUSION: Pregnancy is an achievable goal for women with transfusion-dependent haemoglobinopathies, although the support of ART may be required in a subset of patients.


Assuntos
Cesárea , Hemoglobinopatias , Recém-Nascido , Gravidez , Humanos , Feminino , Estudos Retrospectivos , Austrália/epidemiologia , Técnicas de Reprodução Assistida , Resultado da Gravidez/epidemiologia , Hemoglobinopatias/complicações , Hemoglobinopatias/epidemiologia , Hemoglobinopatias/terapia
9.
J Korean Med Sci ; 39(20): e168, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38804012

RESUMO

BACKGROUND: South Korea faces a critical challenge with its rapidly declining fertility rates and an increasingly aging population, which significantly impacts the country's blood supply and demand. Despite these nationwide trends, regional disparities in blood supply and demand have not been thoroughly studied. METHODS: This research utilized blood donation data from the Korean Red Cross and blood transfusion data from the Health Insurance Review and Assessment Service. We analyzed these datasets in conjunction with regional population projections to simulate blood supply and demand from 2021 to 2050 across South Korea. Sensitivity analyses were conducted to assess the impact of various factors, including the number of donors, age eligibility criteria for donations, frequency of donations, and blood discard rates. RESULTS: Our projections indicate a decreasing trend in blood supply, from 2.6 million units in 2021 to 1.4 million units by 2050, while demand is expected to peak at 5.1 million units by 2045 before declining. Metropolitan areas, particularly Gyeonggi Province, are projected to experience the most severe shortages. Sensitivity analyses suggest that increasing the donation frequency of existing donors and relaxing age eligibility criteria are more effective strategies in addressing these imbalances than merely increasing the number of new donors. Blood discard rates showed minimal impact on the overall blood shortage. CONCLUSION: The findings emphasize the urgent need for targeted strategies to mitigate national and regional blood supply shortages in South Korea. Encouraging frequent donations from experienced donors and broadening eligibility criteria are critical steps toward stabilizing the blood supply amidst demographic shifts. These strategies must be prioritized to address the impending regional disparities in blood availability.


Assuntos
Doadores de Sangue , Humanos , República da Coreia , Doadores de Sangue/estatística & dados numéricos , Adulto , Pessoa de Meia-Idade , Feminino , Masculino , Adolescente , Adulto Jovem , Idoso
10.
FASEB J ; 36(4): e22245, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35262963

RESUMO

Antenatal synthetic glucocorticoids (sGCs) are a life-saving treatment in managing pre-term birth. However, off-target effects of sGCs can impact blood-brain barrier (BBB) drug transporters essential for fetal brain protection, including P-glycoprotein (P-gp/Abcb1) and breast cancer resistance protein (BCRP/Abcg2). We hypothesized that maternal antenatal sGC treatment modifies BBB function in juvenile offspring in a sex-dependent manner. Thus, the objective of this study was to determine the long-term impact of a single or multiple courses of betamethasone on P-gp/Abcb1 and BCRP/Abcg2 expression and function at the BBB. Pregnant guinea pigs (N = 42) received 3 courses (gestation days (GDs) 40, 50, and 60) or a single course (GD50) of betamethasone (1 mg/kg) or vehicle (saline). Cerebral microvessels and brain endothelial cells (BEC) were collected from the post-natal day (PND) 14 offspring to measure protein, gene expression, and function of the drug transporters P-gp/Abcb1 and BCRP/Abcg2. P-gp protein expression was decreased (p < .05) in microvessels from male offspring that had been exposed to multiple courses and a single course of sGC, in utero. Multiple courses of sGC resulted in a significant decrease in P-gp function in BECs from males (p < .05), but not females. There was a very strong trend for increased P-gp function in males compared to females (p = .055). Reduced P-gp expression and function at the BBB of young male offspring following multiple prenatal sGC exposures, is clinically relevant as many drugs administered postnatally are P-gp substrates. These novel sex differences in drug transporter function may underlie potential sexual dimorphism in drug sensitivity and toxicity in the newborn and juvenile brain.


Assuntos
Barreira Hematoencefálica , Glucocorticoides , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Betametasona/metabolismo , Betametasona/farmacologia , Barreira Hematoencefálica/metabolismo , Células Endoteliais/metabolismo , Feminino , Glucocorticoides/metabolismo , Glucocorticoides/farmacologia , Cobaias , Masculino , Proteínas de Neoplasias/metabolismo , Gravidez
11.
Am J Obstet Gynecol ; 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38042244

RESUMO

BACKGROUND: Maternal depression is a serious condition that affects up to 1 in 7 pregnancies. Despite evidence linking maternal depression to pregnancy complications and adverse fetal outcomes, there remain large gaps in its identification and treatment. More work is needed to define the specific timing and severity of depression that most urgently requires intervention, where feasible, to protect maternal health and the developing fetus. OBJECTIVE: This study aimed to examine whether the timing and severity of maternal depression and/or anxiety during pregnancy affect child executive functioning at age 4.5 years. Executive functioning in the preschool years is a strong predictor of both school readiness and long-term quality of life. STUDY DESIGN: This longitudinal observational pregnancy cohort study included a sample of 323 mother-child dyads taking part in the Ontario Birth Study, an open pregnancy cohort in Toronto, Ontario, Canada. Maternal symptoms of depression and anxiety were assessed at 12 to 16 and 28 to 32 weeks of gestation and at the time of child testing at age 4.5 years using the 4-item Patient Health Questionnaire. Child executive functioning was measured during a home visit using standardized computerized administration of the Flanker test (a measure of attention) and the Dimensional Change Card Sort (a measure of cognitive flexibility). Stepwise linear regressions, controlling for possible confounding variables, were used to assess the predictive value of continuous measures of maternal depression and/or anxiety symptoms at each assessment time on the Flanker test and Dimensional Change Card Sort. Posthoc general linear models were used to assess whether maternal depression severity categories (no symptom, mild symptoms, or probable major depressive disorder) were helpful in identifying children at risk. RESULTS: Across all children, after controlling for potential confounds, greater maternal depressive symptoms at weeks 12 to 16 weeks of gestation predicted worse performance on both the Flanker test (ΔR2=0.058; P<.001) and the Dimensional Change Card Sort (ΔR2=0.017; P=.018). Posthoc general linear modeling further demonstrated that the children of mothers meeting the screening criteria for major depression in early pregnancy scored 11.3% lower on the Flanker test and 9.8% lower on the Dimensional Change Card Sort than the children of mothers without maternal depressive symptoms in early pregnancy. Mild depressive symptoms had no significant effect on executive function scores. There was no significant effect of anxiety symptoms or maternal antidepressant use in early pregnancy or pandemic conditions or maternal symptoms in later pregnancy or at the time of child testing on either the Flanker or Dimensional Change Card Sort results. CONCLUSION: This study demonstrated that fetal exposure to maternal major depression, but not milder forms of depression, at 12 to 16 weeks of gestation is associated with impaired executive functioning in the preschool years. Child executive functioning is crucial for school readiness and predicts long-term quality of life. This emphasizes an urgent need to improve the recognition and treatment of maternal major depression, particularly in early pregnancy, to limit its negative effects on the patient and on child cognitive development.

12.
Pediatr Res ; 93(4): 959-963, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35794252

RESUMO

BACKGROUND: Studies have suggested a link between prenatal maternal acetaminophen use and adverse developmental outcomes in children. However, there exists a knowledge gap regarding overall cognitive development and use of acetaminophen, especially concerning the timing of use in pregnancy. This study aimed to characterize the relationship between maternal acetaminophen use and cognitive development at 4 years. METHODS: This analysis included data collected throughout pregnancy and delivery from women in the Ontario Birth Study prospective cohort from 2013 to 2019 and from the NIH Toolbox Early Childhood Cognition battery administered to 4-year-old children between 2018 and 2021 (n = 436). The exposure was maternal acetaminophen use and the primary outcome was a cognition composite score. The relationship between exposure and outcome was determined using Poisson regression with a robust error variance. RESULTS: We did not observe any association between maternal acetaminophen intake any time before or during pregnancy and low cognition composite score of offspring. The IRR of suboptimal overall cognition was 1.38 (0.78-2.45), 1.22 (0.67-2.22), 0.80 (0.44-1.47), and 1.56 (0.74-3.29) for maternal use of acetaminophen before, in early, late, or overall pregnancy, respectively. CONCLUSION: Current data do not provide evidence to support a relationship of maternal acetaminophen use during pregnancy with adverse cognitive effects at 4 years. IMPACT: Acetaminophen use during pregnancy may influence the risk of child neurocognitive disorders, but there is conflicting evidence of its relationship to sub-clinical measures of cognitive development such as executive function. The study design allowed us to examine the role of timing of acetaminophen use in its relationship with cognitive development, based on a validated and standardized tablet-administered instrument for children, instead of a teacher or parent report. We did not observe a clear relationship between maternal acetaminophen use at different timepoints during pregnancy and child cognitive development.


Assuntos
Acetaminofen , Efeitos Tardios da Exposição Pré-Natal , Gravidez , Humanos , Feminino , Pré-Escolar , Acetaminofen/efeitos adversos , Estudos Prospectivos , Ontário , Cognição
13.
Cell Mol Life Sci ; 79(8): 415, 2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35821142

RESUMO

The blood-brain barrier (BBB) provides essential neuroprotection from environmental toxins and xenobiotics, through high expression of drug efflux transporters in endothelial cells of the cerebral capillaries. However, xenobiotic exposure, stress, and inflammatory stimuli have the potential to disrupt BBB permeability in fetal and post-natal life. Understanding the role and ability of the BBB in protecting the developing brain, particularly with respect to drug/toxin transport, is key to promoting long-term brain health. Drug transporters, particularly P-gp and BCRP are expressed in early gestation at the developing BBB and have a crucial role in developmental homeostasis and fetal brain protection. We have highlighted several factors that modulate drug transporters at the developing BBB, including synthetic glucocorticoid (sGC), cytokines, maternal infection, and growth factors. Some factors have the potential to increase expression and function of drug transporters and increase brain protection (e.g., sGC, transforming growth factor [TGF]-ß). However, others inhibit drug transporters expression and function at the BBB, increasing brain exposure to xenobiotics (e.g., tumor necrosis factor [TNF], interleukin [IL]-6), negatively impacting brain development. This has implications for pregnant women and neonates, who represent a vulnerable population and may be exposed to drugs and environmental toxins, many of which are P-gp and BCRP substrates. Thus, alterations in regulated transport across the developing BBB may induce long-term changes in brain health and compromise pregnancy outcome. Furthermore, a large portion of neonatal adverse drug reactions are attributed to agents that target or access the nervous system, such as stimulants (e.g., caffeine), anesthetics (e.g., midazolam), analgesics (e.g., morphine) and antiretrovirals (e.g., Zidovudine); thus, understanding brain protection is key for the development of strategies to protect the fetal and neonatal brain.


Assuntos
Transportadores de Cassetes de Ligação de ATP , Barreira Hematoencefálica , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Trifosfato de Adenosina/metabolismo , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Células Endoteliais/metabolismo , Feminino , Humanos , Recém-Nascido , Interleucina-6/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Proteínas de Neoplasias/metabolismo , Gravidez , Xenobióticos/metabolismo
14.
Monogr Soc Res Child Dev ; 88(3): 7-130, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37953661

RESUMO

Scientists have, for some time, recognized that development unfolds in numerous settings, including families, schools, neighborhoods, and organized and unorganized activity settings. Since the turn of the 20th century, the body of mainstream neighborhood effects scholarship draws heavily from the early 20th century Chicago School of Sociology frameworks and have been situating development in neighborhood contexts and working to identify the structures and processes via which neighborhoods matter for a range of developmental outcomes, especially achievement, behavioral and emotional problems, and sexual activity. From this body of work, two new areas of developmental scholarship are emerging. Both areas are promising for advancing an understanding of child development in context. First, cultural-developmental neighborhood researchers are advancing neighborhood effects research that explicitly recognizes the ways that racial, ethnic, cultural, and immigrant social positions matter for neighborhood environments and for youths' developmental demands, affordances, experiences, and competencies. This body of work substantially expands the range of developmental outcomes examined in neighborhood effects scholarship to recognize normative physical, emotional, cognitive, behavioral, social, and cultural competencies that have largely been overlooked in neighborhood effects scholarship that espoused a more color-blind developmental approach. Second, activity space neighborhood researchers are recognizing that residential neighborhoods have important implications for broader activity spaces-or the set of locations and settings to which youth are regularly exposed, including, for example, schools, work, organized activities, and hang-outs. They are using newer technologies and geographic frameworks to assess exposure to residential neighborhood and extra-neighborhood environments. These perspectives recognize that time (i.e., from microtime to mesotime) and place are critically bound and that exposures can be operationalized at numerous levels of the ecological system (i.e., from microsystems to macrosystems). These frameworks address important limitations of prior development in context scholarship by addressing selection and exposure. Addressing selection involves recognizing that families have some degree of choice when selecting into settings and variables that predict families' choices (e.g., income) also predict development. Considering exposure involves recognizing that different participants or residents experience different amounts of shared and nonshared exposures, resulting in both under-and over-estimation of contextual effects. Activity space scholars incorporate exposure to the residential neighborhood environments, but also to other locations and settings to which youth are regularly exposed, like schools, after-school settings, work, and hang-outs. Unfortunately, the cultural-development and activity space streams, which have both emerged from early 20th century work on neighborhood effects on development, have been advancing largely independently. Thus, the overarching aim of this monograph is to integrate scholarship on residential neighborhoods, cultural development, and activity spaces to advance a framework that can support a better understanding of development in context for diverse groups. In Chapters I and II we present the historical context of the three streams of theoretical, conceptual, and methodological research. We also advance a comprehensive cultural-developmental activity space framework for studying development in context among children, youth, and families that are ethnically, racially, and culturally heterogeneous. This framework actively recognized diversity in ethnic, racial, immigrant, and socioeconomic social positions. In Chapters III-V we advance specific features of the framework, focusing on: (1) the different levels of nested and nonnested ecological systems that can be captured and operationalized with activity space methods, (2) the different dimensions of time and exposures or experiences that can be captured and operationalized by activity space methods, and (3) the importance of settings structures and social processes for identifying underlying mechanisms of contextual effects on development. Structures are setting features related to the composition and spatial arrangement of people and institutions (e.g., socioeconomic disadvantage, ethnic/racial compositions). Social processes represent the collective social dynamics that take place in settings, like social interactions, group activities, experiences with local institutions, mechanisms of social control, or shared beliefs. In Chapter VI, we highlight a range of methodological and empirical exemplars from the United States that are informed by our comprehensive cultural-developmental activity space framework. These exemplars feature both quantitative and qualitative methods, including method mixing. These exemplars feature both quantitative and qualitative methods, including method mixing. The exemplars also highlight the application of the framework across four different samples from populations that vary in terms of race, ethnicity, gender, age, socioeconomic status (SES), geographic region, and urbanicity. They capture activity space characteristics and features in a variety of ways, in addition to incorporating family shared and nonshared activity space exposures. Finally, in Chapter VII we summarize the contributions of the framework for advancing a more comprehensive science of development in context, one that better realizes major developmental theories emphasizing persons, processes, contexts, and time. Additionally, we offer a place-based, culturally informed developmental research agenda to meet the needs of an increasingly diverse population.


Assuntos
Desenvolvimento Infantil , Etnicidade , Criança , Humanos , Adolescente , Estados Unidos , Projetos de Pesquisa
15.
Am J Perinatol ; 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37935374

RESUMO

OBJECTIVE: Animal literature has suggested that the impact of antenatal corticosteroids (ACS) may vary by infant sex. Our objective was to assess the impact of infant sex on the use of multiple courses versus a single course of ACS and perinatal outcomes. STUDY DESIGN: We conducted a secondary analysis of the Multiple Courses of Antenatal Corticosteroids for Preterm Birth trial, which randomly allocated pregnant people to multiple courses versus a single course of ACS. Our primary outcome was a composite of perinatal mortality or clinically significant neonatal morbidity (including neonatal death, stillbirth, severe respiratory distress syndrome, intraventricular hemorrhage [grade III or IV], cystic periventricular leukomalacia, and necrotizing enterocolitis [stage II or III]). Secondary outcomes included individual components of the primary outcome as well as anthropometric measures. Baseline characteristics were compared between participants who received multiple courses versus a single course of ACS. An interaction between exposure to ACS and infant sex was assessed for significance and multivariable regression analyses were conducted with adjustment for predefined covariates, when feasible. RESULTS: Data on 2,300 infants were analyzed. The interaction term between treatment status (multiple courses vs. a single course of ACS) and infant sex was not significant for the primary outcome (p = 0.86), nor for any of the secondary outcomes (p > 0.05). CONCLUSION: Infant sex did not modify the association between exposure to ACS and perinatal outcomes including perinatal mortality or neonatal morbidity or anthropometric outcomes. However, animal literature indicates that sex-specific differences after exposure to ACS may emerge over time and thus investigating long-term sex-specific outcomes warrants further attention. KEY POINTS: · We explored the impact of infant sex on perinatal outcomes after multiple versus a single course of ACS.. · Infant sex was not a significant effect modifier of ACS exposure and perinatal outcomes.. · Animal literature indicates that sex-specific differences after ACS exposure may emerge over time.. · Further investigation of long-term sex-specific outcomes is warranted..

16.
Hum Brain Mapp ; 43(16): 5066-5080, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36097409

RESUMO

While neuroimaging studies have identified brain regions associated with single word reading, its three constituents, namely, orthography, phonology, and meaning, and the functional connectivity of their networks remain underexplored. This study examined the neurocognitive underpinnings of these neural activations and functional connectivity of the identified brain regions using a within-subject design. Thirty-one native Mandarin speakers performed orthographic, phonological, and semantic judgment tasks during functional magnetic resonance imaging. The results indicated that the three processes shared a core network consisting of a large region in the left prefrontal cortex, fusiform gyrus, and medial superior frontal gyrus but not the superior temporal gyrus. Orthographic processing more strongly recruited the left dorsolateral prefrontal cortex, left superior parietal lobule and bilateral fusiform gyri; semantic processing more strongly recruited the left inferior frontal gyrus and left middle temporal gyrus, whereas phonological processing more strongly activated the dorsal part of the precentral gyrus. Functional connectivity analysis identified a posterior visuospatial network and a frontal phonosemantic network interfaced by the left middle frontal gyrus. We conclude that reading Chinese recruits cognitive resources that correspond to basic task demands with unique features best explained in connection with the individual reading subprocesses.


Assuntos
Encéfalo , Idioma , Processos Mentais , Humanos , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Mapeamento Encefálico , Imageamento por Ressonância Magnética , Leitura , Semântica , Processos Mentais/fisiologia
17.
Pediatr Res ; 92(5): 1450-1457, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35288638

RESUMO

BACKGROUND: Maternal prenatal psychological distress (PPD) is increasingly linked to sub-optimal child neurodevelopment. Daily intake of prenatal vitamin during pre-conception and early pregnancy may ameliorate the effects of PPD on cognition in the offspring. METHODS: PPD was assessed in early (12-16 weeks) and late (28-32 weeks) gestation in the Ontario Birth Study. Prenatal vitamin supplement intake information was collected in early gestation. Child cognition at 4 years was assessed using the NIH Toolbox. Poisson regression was used to investigate associations between PPD and/or prenatal vitamin intake and child cognition. RESULTS: Four hundred and eighteen mother-child dyads were assessed. Moderate-severe PPD experienced during early gestation was associated with reduced cognition (adjusted incidence rate ratio (IRRadj) = 3.71, 95% confidence interval (CI): 1.57-8.77, P = 0.003). Daily intake of prenatal vitamins was not associated with cognition (IRRadj = 1.34, 95% CI: 0.73-2.46, P = 0.34). Upon stratification, the experience of mild-severe PPD with daily intake of prenatal vitamins was associated with higher incident rates of suboptimal cognition compared to children of women with daily prenatal vitamin intake without any episode of PPD (IRRadj = 2.88, 95% CI: 1.1-7.4). CONCLUSIONS: Moderate-severe PPD in early pregnancy is associated with poor cognition in children and daily intake of prenatal vitamin did not ameliorate this association. IMPACT: Our findings expand on existing literature by highlighting that exposure to prenatal psychological distress (PPD), in moderate-to-severe form, in the early stages of pregnancy, can have detrimental effects on the offspring's cognitive development at 4 years. Overall, prenatal vitamin intake did not ameliorate the effects of PPD. Early screening and treatment of prenatal maternal mental illness is crucial.


Assuntos
Efeitos Tardios da Exposição Pré-Natal , Angústia Psicológica , Gravidez , Humanos , Feminino , Estado Nutricional , Família , Cognição , Vitaminas/uso terapêutico , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Desenvolvimento Infantil
18.
Transpl Infect Dis ; 24(5): e13907, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36254522

RESUMO

BACKGROUND: Beta-lactam allergies (BLAs) are common in hospitalized patients, including transplant recipients. BLA is associated with decreased use of preferred surgical site infection (SSI) prophylaxis and increased SSIs, but this has not been studied in the transplant population. METHODS: We reviewed adult heart, kidney, and liver transplant recipients between January 1, 2016 and December 31, 2019 to characterize reported BLA and collect SSI prophylaxis regimens at time of transplant. We compared the use of preferred SSI prophylaxis and SSI incidence based on reported BLA status. Post hoc we collected antibiotic days of therapy (DOT) (excluding pneumocystis prophylaxis) in the 30-day period posttransplant for patients without SSI. We utilized descriptive statistics for comparisons. RESULTS: Of 691 patients included (116 heart, 400 kidney, and 175 liver transplant recipients), 118 (17%) reported BLA. Rash and hives were the two most reported BLA reactions (36% and 24%), categorized as potential T-cell mediated and IgE mediated, respectively. Preferred SSI prophylaxis was prescribed in 13 (11%) patients with BLA and 573 (92%) without BLA (p < .001). No difference could be detected in SSI incidence between BLA and non-BLA patients (4.2 vs. 4.3%, p = 1.0). Of 659 without SSI, 169 (25.6%) received antibiotics within 30 days of transplant; mean antibiotic DOT for BLA and non-BLA patients were 3.5 ± 8.0 versus 2.3 ± 5.8, p = .12. CONCLUSION: BLA transplant recipients received nonpreferred SSI prophylaxis more frequently than non-BLA recipients, but there was no difference in 30-day SSIs between the groups. One-fourth of solid organ transplant recipients received systemic antibiotics within 30 days of transplant.


Assuntos
Hipersensibilidade , Transplante de Órgãos , Adulto , Antibacterianos/uso terapêutico , Antibioticoprofilaxia/efeitos adversos , Humanos , Hipersensibilidade/complicações , Hipersensibilidade/tratamento farmacológico , Imunoglobulina E , Transplante de Órgãos/efeitos adversos , Estudos Retrospectivos , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/etiologia , Infecção da Ferida Cirúrgica/prevenção & controle , Transplantados , beta-Lactamas/uso terapêutico
19.
Am J Perinatol ; 39(6): 592-600, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-33053595

RESUMO

OBJECTIVE: A single course of synthetic antenatal corticosteroids is standard care for women considered to be at risk for preterm birth before 34 weeks of gestation. While the intended target is the fetal lung, the fetal brain contains remarkably high levels of glucocorticoid receptors in structures critical in the regulation of behavior and endocrine function. Negative programming signals may occur which can lead to permanent maladaptive changes and predispose the infant/child to an increased risk in physical, mental, and developmental disorders. METHODS: Framed around these areas of concerns for physical, mental, and developmental disorders, this narrative review drew on studies (animal and clinical), evaluating the long-term effects of antenatal corticosteroids to present the case that a more targeted approach to the use of antenatal corticosteroids for the betterment of the fetus urgently needed. RESULTS: Studies raised concerns about the potential negative long-term consequences, especially for the exposed fetus who was born beyond the period of the greatest benefit from antenatal corticosteroids. The long-term consequences are more subtle in nature and usually manifest later in life, often beyond the scope of most clinical trials. CONCLUSION: Continued research is needed to identify sufficient safety data, both short term and long term. Caution in the use of antenatal corticosteroids should be exercised while additional work is undertaken to optimize dosing strategies and better identify women at risk of preterm birth prior to administration of antenatal corticosteroids. KEY POINTS: · A single-course ACS is a remarkable therapy with substantial benefits.. · There is a potential of long-term neurodevelopmental consequences in the ACS-exposed fetus.. · There is a need to improve dosing strategies and identification of appropriate at risk women..


Assuntos
Nascimento Prematuro , Corticosteroides/efeitos adversos , Animais , Feminino , Feto , Humanos , Recém-Nascido , Parto , Gravidez , Nascimento Prematuro/induzido quimicamente , Nascimento Prematuro/prevenção & controle , Cuidado Pré-Natal
20.
Microvasc Res ; 138: 104232, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34416267

RESUMO

The mechanisms by which the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) induces neurological complications remain to be elucidated. We aimed to identify possible effects of hypoxia on the expression of SARS-CoV-2 cell entry mediators, angiotensin-converting enzyme 2 (ACE2) receptor and transmembrane protease serine 2 (TMPRSS2) protein, in human brain endothelial cells, in vitro. hCMEC/D3 cells were exposed to different oxygen tensions: 20% (Control group), 8% or 2% O2 (Hypoxia groups). Cells were harvested 6-, 24- and 48 h following hypoxic challenge for assessment of mRNA and protein, using qPCR and Western Blot. The response of the brain endothelial cells to hypoxia was replicated using modular incubator chambers. We observed an acute increase (6 h, p < 0.05), followed by a longer-term decrease (48 h, p < 0.05) in ACE2 mRNA and protein expression, accompanied by reduced expression of TMPRSS2 protein levels (48 h, p < 0.05) under the more severe hypoxic condition (2% O2). No changes in levels of von Willebrand Factor (vWF - an endothelial cell damage marker) or interleukin 6 (IL-6 - a pro-inflammatory cytokine) mRNA were observed. We conclude that hypoxia regulates brain endothelial cell ACE2 and TMPRSS2 expression in vitro, which may indicate human brain endothelial susceptibility to SARS-CoV-2 infection and subsequent brain sequelae.


Assuntos
Enzima de Conversão de Angiotensina 2/metabolismo , Encéfalo/irrigação sanguínea , COVID-19/virologia , Células Endoteliais/virologia , SARS-CoV-2/patogenicidade , Serina Endopeptidases/metabolismo , Internalização do Vírus , Enzima de Conversão de Angiotensina 2/genética , COVID-19/enzimologia , Hipóxia Celular , Linhagem Celular , Células Endoteliais/enzimologia , Regulação da Expressão Gênica , Interações Hospedeiro-Patógeno , Humanos , Serina Endopeptidases/genética
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