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1.
EMBO J ; 42(15): e112900, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37350545

RESUMO

The scaffolding protein angiomotin (AMOT) is indispensable for vertebrate embryonic angiogenesis. Here, we report that AMOT undergoes cleavage in the presence of lysophosphatidic acid (LPA), a lipid growth factor also involved in angiogenesis. AMOT cleavage is mediated by aspartic protease DNA damage-inducible 1 homolog 2 (DDI2), and the process is tightly regulated by a signaling axis including neurofibromin 2 (NF2), tankyrase 1/2 (TNKS1/2), and RING finger protein 146 (RNF146), which induce AMOT membrane localization, poly ADP ribosylation, and ubiquitination, respectively. In both zebrafish and mice, the genetic inactivation of AMOT cleavage regulators leads to defective angiogenesis, and the phenotype is rescued by the overexpression of AMOT-CT, a C-terminal AMOT cleavage product. In either physiological or pathological angiogenesis, AMOT-CT is required for vascular expansion, whereas uncleavable AMOT represses this process. Thus, our work uncovers a signaling pathway that regulates angiogenesis by modulating a cleavage-dependent activation of AMOT.


Assuntos
Angiomotinas , Peixe-Zebra , Animais , Camundongos , Peixe-Zebra/metabolismo , Proteínas dos Microfilamentos/metabolismo , Peptídeo Hidrolases , Peptídeos e Proteínas de Sinalização Intercelular/genética
2.
Cell ; 138(3): 525-36, 2009 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-19665974

RESUMO

Modulation of intracellular chloride concentration ([Cl(-)](i)) plays a fundamental role in cell volume regulation and neuronal response to GABA. Cl(-) exit via K-Cl cotransporters (KCCs) is a major determinant of [Cl(-)](I); however, mechanisms governing KCC activities are poorly understood. We identified two sites in KCC3 that are rapidly dephosphorylated in hypotonic conditions in cultured cells and human red blood cells in parallel with increased transport activity. Alanine substitutions at these sites result in constitutively active cotransport. These sites are highly phosphorylated in plasma membrane KCC3 in isotonic conditions, suggesting that dephosphorylation increases KCC3's intrinsic transport activity. Reduction of WNK1 expression via RNA interference reduces phosphorylation at these sites. Homologous sites are phosphorylated in all human KCCs. KCC2 is partially phosphorylated in neonatal mouse brain and dephosphorylated in parallel with KCC2 activation. These findings provide insight into regulation of [Cl(-)](i) and have implications for control of cell volume and neuronal function.


Assuntos
Simportadores/química , Simportadores/metabolismo , Sequência de Aminoácidos , Substituição de Aminoácidos , Animais , Humanos , Camundongos , Dados de Sequência Molecular , Fosforilação , Alinhamento de Sequência , Cotransportadores de K e Cl-
3.
Nature ; 564(7734): 119-124, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30455424

RESUMO

Haematopoietic stem and progenitor cells (HSPCs) give rise to all blood lineages that support the entire lifespan of vertebrates1. After HSPCs emerge from endothelial cells within the developing dorsal aorta, homing allows the nascent cells to anchor in their niches for further expansion and differentiation2-5. Unique niche microenvironments, composed of various blood vessels as units of microcirculation and other niche components such as stromal cells, regulate this process6-9. However, the detailed architecture of the microenvironment and the mechanism for the regulation of HSPC homing remain unclear. Here, using advanced live imaging and a cell-labelling system, we perform high-resolution analyses of the HSPC homing in caudal haematopoietic tissue of zebrafish (equivalent to the fetal liver in mammals), and reveal the role of the vascular architecture in the regulation of HSPC retention. We identify a VCAM-1+ macrophage-like niche cell population that patrols the inner surface of the venous plexus, interacts with HSPCs in an ITGA4-dependent manner, and directs HSPC retention. These cells, named 'usher cells', together with caudal venous capillaries and plexus, define retention hotspots within the homing microenvironment. Thus, the study provides insights into the mechanism of HSPC homing and reveals the essential role of a VCAM-1+ macrophage population with patrolling behaviour in HSPC retention.


Assuntos
Células Endoteliais/citologia , Células-Tronco Hematopoéticas/citologia , Macrófagos/metabolismo , Nicho de Células-Tronco , Molécula 1 de Adesão de Célula Vascular/metabolismo , Animais , Diferenciação Celular , Movimento Celular , Microambiente Celular , Integrinas/genética , Integrinas/metabolismo , Peixe-Zebra , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
4.
Sensors (Basel) ; 24(9)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38732816

RESUMO

Target detection technology based on unmanned aerial vehicle (UAV)-derived aerial imagery has been widely applied in the field of forest fire patrol and rescue. However, due to the specificity of UAV platforms, there are still significant issues to be resolved such as severe omission, low detection accuracy, and poor early warning effectiveness. In light of these issues, this paper proposes an improved YOLOX network for the rapid detection of forest fires in images captured by UAVs. Firstly, to enhance the network's feature-extraction capability in complex fire environments, a multi-level-feature-extraction structure, CSP-ML, is designed to improve the algorithm's detection accuracy for small-target fire areas. Additionally, a CBAM attention mechanism is embedded in the neck network to reduce interference caused by background noise and irrelevant information. Secondly, an adaptive-feature-extraction module is introduced in the YOLOX network's feature fusion part to prevent the loss of important feature information during the fusion process, thus enhancing the network's feature-learning capability. Lastly, the CIoU loss function is used to replace the original loss function, to address issues such as excessive optimization of negative samples and poor gradient-descent direction, thereby strengthening the network's effective recognition of positive samples. Experimental results show that the improved YOLOX network has better detection performance, with mAP@50 and mAP@50_95 increasing by 6.4% and 2.17%, respectively, compared to the traditional YOLOX network. In multi-target flame and small-target flame scenarios, the improved YOLO model achieved a mAP of 96.3%, outperforming deep learning algorithms such as FasterRCNN, SSD, and YOLOv5 by 33.5%, 7.7%, and 7%, respectively. It has a lower omission rate and higher detection accuracy, and it is capable of handling small-target detection tasks in complex fire environments. This can provide support for UAV patrol and rescue applications from a high-altitude perspective.

5.
Sensors (Basel) ; 24(14)2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39066111

RESUMO

In air traffic control (ATC), speech communication with radio transmission is the primary way to exchange information between the controller and the pilot. As a result, the integration of automatic speech recognition (ASR) systems holds immense potential for reducing controllers' workload and plays a crucial role in various ATC scenarios, which is particularly significant for ATC research. This article provides a comprehensive review of ASR technology's applications in the ATC communication system. Firstly, it offers a comprehensive overview of current research, including ATC corpora, ASR models, evaluation measures and application scenarios. A more comprehensive and accurate evaluation methodology tailored for ATC is proposed, considering advancements in communication sensing systems and deep learning techniques. This methodology helps researchers in enhancing ASR systems and improving the overall performance of ATC systems. Finally, future research recommendations are identified based on the primary challenges and issues. The authors sincerely hope this work will serve as a clear technical roadmap for ASR endeavors within the ATC domain and make a valuable contribution to the research community.

6.
Arterioscler Thromb Vasc Biol ; 42(6): 772-788, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35477278

RESUMO

BACKGROUND: Arteriogenesis plays a critical role in maintaining adequate tissue blood supply and is related to a favorable prognosis in arterial occlusive diseases. Strategies aimed at promoting arteriogenesis have thus far not been successful because the factors involved in arteriogenesis remain incompletely understood. Previous studies suggest that evolutionarily conserved KANK4 (KN motif and ankyrin repeat domain-containing proteins 4) might involve in vertebrate vessel development. However, how the KANK4 regulates vessel function remains unknown. We aim to determine the role of endothelial cell-specifically expressed KANK4 in arteriogenesis. METHODS: The role of KANK4 in regulating arteriogenesis was evaluated using Kank4-/- and KANK4iECOE mice. Molecular mechanisms underlying KANK4-potentiated arteriogenesis were investigated by employing RNA transcriptomic profiling and mass spectrometry analysis. RESULTS: By analyzing Kank4-EGFP reporter mice, we showed that KANK4 was specifically expressed in endothelial cells. In particular, KANK4 displayed a dynamic expression pattern from being ubiquitously expressed in all endothelial cells of the developing vasculature to being explicitly expressed in the endothelial cells of arterioles and arteries in matured vessels. In vitro microfluidic chip-based vascular morphology analysis and in vivo hindlimb ischemia assays using Kank4-/- and KANK4iECOE mice demonstrated that deletion of KANK4 impaired collateral artery growth and the recovery of blood perfusion, whereas KANK4 overexpression leads to increased vessel caliber and blood perfusion. Bulk RNA sequencing and Co-immunoprecipitation/mass spectrometry (Co-IP/MS) analysis identified that KANK4 promoted EC proliferation and collateral artery remodeling through coupling VEGFR2 (vascular endothelial growth factor receptor 2) to TALIN-1, which augmented the activation of the VEGFR2 signaling cascade. CONCLUSIONS: This study reveals a novel role for KANK4 in arteriogenesis in response to ischemia. KANK4 links VEGFR2 to TALIN-1, resulting in enhanced VEGFR2 activation and increased EC proliferation, highlighting that KANK4 is a potential therapeutic target for promoting arteriogenesis for arterial occlusive diseases.


Assuntos
Arteriopatias Oclusivas , Neovascularização Fisiológica , Animais , Arteriopatias Oclusivas/metabolismo , Circulação Colateral , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Membro Posterior/irrigação sanguínea , Isquemia , Camundongos , Camundongos Knockout , Músculo Esquelético/irrigação sanguínea , Fluxo Sanguíneo Regional , Talina , Fator A de Crescimento do Endotélio Vascular/metabolismo
7.
Ecotoxicol Environ Saf ; 249: 114414, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36516626

RESUMO

BACKGROUND: Based on self-report questionnaires, two previous epidemiological studies investigated the association between the exposure of women to antibiotics and their fertility. However, biomonitoring studies on low-dose antibiotic exposure, mainly from food and water, and its relation to the risk of infertility are missing. METHODS: Based on a case-control study design, 302 women with infertility (144 primary infertility, 158 secondary infertility) and 302 women with normal fertility, all aged 20-49 years, were recruited from Anhui Province, China, in 2020 and 2021. A total of 41 common antibiotics and two antibiotic metabolites in urine samples were determined by liquid chromatography-triple quadrupole tandem mass spectrometry (LC-QqQ-MS/MS). RESULTS: Twenty-eight antibiotics with detection rates from 10% to 100% in both cases (median concentration: ∼2.294 ng/mL) and controls (∼1.596 ng/mL) were included in the analysis. Logistic regression analysis revealed that after controlling for confounding factors, high concentrations of eight individual antibiotics (sulfamethoxazole, sulfaclozine, sulfamonomethoxine, penicillin G, chlorotetracycline, ofloxacin, norfloxacin, and cyadox) and four antibiotic classes (sulfonamides, tetracyclines, quinoxalines, and veterinary antibiotics) were related to a high risk of female infertility, with odds ratios (ORs) ranging from 1.30 to 2.86, except for chlorotetracycline (OR = 6.34), while another nine individual antibiotics (sulfamethazine, azithromycin, cefaclor, amoxicillin, oxytetracycline, pefloxacin, sarafloxacin, enrofloxacin, and florfenicol) and classes of chloramphenicol analogs and human antibiotics were related to a reduced risk of infertility, with ORs ranging from 0.70 to 0.20. Based on restricted cubic spline models after controlling for confounding factors, we observed that the relationship between all of the above protective antibiotics and infertility was nonlinear: A certain concentration could reduce the risk of female infertility while exceeding a safe dose could increase the risk of infertility. CONCLUSION: These results provide preliminary evidence that the effects of antibiotics on female fertility vary based on the active ingredient and usage and imply the importance of exposure dose. Future studies are needed to verify these results by controlling for multiple confounding factors.


Assuntos
Clortetraciclina , Infertilidade Feminina , Humanos , Feminino , Antibacterianos/análise , Espectrometria de Massas em Tandem/métodos , Clortetraciclina/análise , Infertilidade Feminina/induzido quimicamente , Infertilidade Feminina/epidemiologia , Estudos de Casos e Controles , China/epidemiologia
8.
Genome Res ; 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31831591

RESUMO

Genome editing by the well-established CRISPR/Cas9 technology has greatly facilitated our understanding of many biological processes. However, a complete whole-genome knockout for any species or model organism has rarely been achieved. Here, we performed a systematic knockout of all the genes (1333) on Chromosome 1 in zebrafish, successfully mutated 1029 genes, and generated 1039 germline-transmissible alleles corresponding to 636 genes. Meanwhile, by high-throughput bioinformatics analysis, we found that sequence features play pivotal roles in effective gRNA targeting at specific genes of interest, while the success rate of gene targeting positively correlates with GC content of the target sites. Moreover, we found that nearly one-fourth of all mutants are related to human diseases, and several representative CRISPR/Cas9-generated mutants are described here. Furthermore, we tried to identify the underlying mechanisms leading to distinct phenotypes between genetic mutants and antisense morpholino-mediated knockdown embryos. Altogether, this work has generated the first chromosome-wide collection of zebrafish genetic mutants by the CRISPR/Cas9 technology, which will serve as a valuable resource for the community, and our bioinformatics analysis also provides some useful guidance to design gene-specific gRNAs for successful gene editing.

9.
Biochem Biophys Res Commun ; 557: 8-13, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-33857842

RESUMO

Precise quantification of vascular developments in Zebrafish requires continuous in-vivo 3D imaging. Here we employed a bi-directional light-sheet illumination microscope to characterize the development process of Zebrafish's intersegmental vessels. A Virtual Reality-based method was used to measure the lengths of intersegmental vessels (ISVs). The quantified growth rates of typical ISVs can be plotted, and unusual growth of some specific vessels was also observed.


Assuntos
Vasos Sanguíneos/embriologia , Embrião não Mamífero/irrigação sanguínea , Microscopia/instrumentação , Peixe-Zebra/embriologia , Animais , Animais Geneticamente Modificados , Vasos Sanguíneos/crescimento & desenvolvimento , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Imageamento Tridimensional/métodos , Iluminação , Microscopia/métodos , Neovascularização Fisiológica , Peixe-Zebra/crescimento & desenvolvimento
10.
Acta Pharmacol Sin ; 42(5): 801-813, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32796956

RESUMO

Grincamycins (GCNs) are a class of angucycline glycosides isolated from actinomycete Streptomyces strains that have potent antitumor activities, but their antitumor mechanisms remain unknown. In this study, we tried to identify the cellular target of grincamycin B (GCN B), one of most dominant and active secondary metabolites, using a combined strategy. We showed that GCN B-selective-induced apoptosis of human acute promyelocytic leukemia (APL) cell line NB4 through increase of ER stress and intracellular reactive oxygen species (ROS) accumulation. Using a strategy of combining phenotype, transcriptomics and protein microarray approaches, we identified that isocitrate dehydrogenase 1(IDH1) was the putative target of GCN B, and confirmed that GCNs were a subset of selective inhibitors targeting both wild-type and mutant IDH1 in vitro. It is well-known that IDH1 converts isocitrate to 2-oxoglutarate (2-OG), maintaining intracellular 2-OG homeostasis. IDH1 and its mutant as the target of GCN B were validated in NB4 cells and zebrafish model. Knockdown of IDH1 in NB4 cells caused the similar phenotype as GCN B treatment, and supplementation of N-acetylcysteine partially rescued the apoptosis caused by IDH1 interference in NB4 cells. In zebrafish model, GCN B effectively restored myeloid abnormality caused by overexpression of mutant IDH1(R132C). Taken together, we demonstrate that IDH1 is one of the antitumor targets of GCNs, suggesting wild-type IDH1 may be a potential target for hematological malignancies intervention in the future.


Assuntos
Antraquinonas/farmacologia , Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Glicosídeos/farmacologia , Isocitrato Desidrogenase/antagonistas & inibidores , Animais , Antraquinonas/metabolismo , Antineoplásicos/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Inibidores Enzimáticos/metabolismo , Glicosídeos/metabolismo , Humanos , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo , Ácidos Cetoglutáricos/metabolismo , Simulação de Acoplamento Molecular , Mutação , Ligação Proteica , Espécies Reativas de Oxigênio/metabolismo , Peixe-Zebra
11.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 38(6): 577-580, 2021 Jun 10.
Artigo em Chinês | MEDLINE | ID: mdl-34096030

RESUMO

OBJECTIVE: To explore the cause of abortion and strategy of prenatal diagnosis for pregnant women with high risk for chromosomal abnormalities by using copy number variation sequencing (CNV-seq) and short tandem repeats (STR) analysis. METHODS: A total of 36 samples were collected, including amniotic fluid, abortion tissue, whole blood, chorionic villi and umbilical cord blood. CNV-seq and STR analysis were carried out to detect microdeletions, microduplications, chromosomal aneuploidies, mosaicisms and triploidies. RESULTS: Among all samples, 1 was detected with 4p15.1p16.3 and 14q11.1q22.1 duplication, 1 was detected with 19p13.3 deletion, 8 were detected with chromosomal aneuploidies, 4 were detected with mosaicisms, two were detected with triploidies. No definite pathogenic CNVs were detected in 20 samples, which yielded a positive detection rate of 44.44%. CONCLUSION: As a high-throughput detection method, CNV-seq has the advantages of rapidity, simplicity and high accuracy. It may suit prenatal diagnosis and analysis of abortion factors in combination with STR analysis.


Assuntos
Aborto Espontâneo , Variações do Número de Cópias de DNA , Aborto Espontâneo/genética , Feminino , Humanos , Cariotipagem , Repetições de Microssatélites , Gravidez , Diagnóstico Pré-Natal
12.
Mutagenesis ; 34(4): 299-306, 2019 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-31613971

RESUMO

Arteriovenous malformation (AVM) is defined as a fast-flow vascular anomaly that shunts blood from arteries directly to veins. This short circuit of blood flow contributes to progressive expansion of draining veins, resulting in ischaemia, tissue deformation and in some severe cases, congestive heart failure. Various medical interventions have been employed to treat AVM, however, management of which remains a huge challenge because of its high recurrence rate and lethal complications. Thus, understanding the underlying mechanisms of AVM development and progression will help direct discovery and a potential cure. Here, we summarize current findings in the field of extracranial AVMs with the aim to provide insight into their aetiology and molecular influences, in the hope to pave the way for future treatment.


Assuntos
Malformações Arteriovenosas/diagnóstico , Malformações Arteriovenosas/genética , Animais , Malformações Arteriovenosas/metabolismo , Biomarcadores , Diagnóstico Diferencial , Gerenciamento Clínico , Suscetibilidade a Doenças , Desenvolvimento Embrionário/genética , Estudos de Associação Genética , Loci Gênicos , Predisposição Genética para Doença , Humanos , Mutação , Fenótipo , Transdução de Sinais , Síndrome , Pesquisa Translacional Biomédica
13.
Eur J Nutr ; 58(1): 291-300, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29236164

RESUMO

PURPOSE: Decrease in activity stress induces skeletal muscle atrophy. A previous study showed that treatment with a high level (20%) of isoflavone inhibits muscle atrophy after short-term denervation (at 4 days) in mice. The present study was designed to elucidate whether the dietary isoflavone aglycone (AglyMax) at a 0.6% prevents denervation-mediated muscle atrophy, based on the modulation of atrogin-1- or apoptosis-dependent signaling. METHODS: Mice were fed either a normal diet or 0.6% AglyMax diet. One week later, the right sciatic nerve was cut. The wet weight, mean fiber area, amount of atrogin-1 and cleaved caspase-3 proteins, and the percentages of apoptotic nuclei were examined in the gastrocnemius muscle at 14 days after denervation. RESULTS: The 0.6% AglyMax diet significantly attenuated denervation-induced decreases in fiber atrophy but not the muscle wet weight. In addition, dietary isoflavone suppressed the denervation-induced apoptosis in spite of there being no significant changes in the amount of cleaved caspase-3 protein. In contrast, the 0.6% AglyMax diet did not significantly modulate the protein expression of atrogin-1 in the denervated muscle of mice. CONCLUSIONS: The isoflavone aglycone (AglyMax) at a 0.6% significantly would modulate muscle atrophy after denervation in mice, probably due to the decrease in apoptosis-dependent signaling.


Assuntos
Isoflavonas/farmacologia , Denervação Muscular , Atrofia Muscular/prevenção & controle , Animais , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos ICR
14.
Clin Endocrinol (Oxf) ; 88(6): 928-935, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29504633

RESUMO

OBJECTIVE: Hypertensive disorders of pregnancy (HDP) have been associated with adverse health outcomes for both mothers and children. Previous studies examining associations of maternal thyroid autoantibodies with HDP indicate conflicting results. The objective of this study was to examine associations of maternal thyroid autoantibody positivity in the first and the second trimesters with the risk of HDP. DESIGN, PARTICIPANTS AND MEASUREMENTS: In the Ma'anshan Birth Cohort study, a population-based prospective study in China, a total of 3474 pregnant women were enrolled between May 2013 and September 2014. Thyroid autoantibodies, including antithyroperoxidase autoantibody (TPOAb) and antithyroglobulin autoantibody (TgAb), as well as thyroid function tests, were measured in both the first and the second trimesters in 2893 pregnant women. Multivariate logistic regression analyses were conducted to calculate the odds ratio (OR) and 95% confidence interval (CI) for the associations between thyroid autoantibodies and HDP. RESULTS: Multivariate logistic regression analyses showed that TPOAb positivity in the first trimester was associated with a 1.80 (95% CI = 1.17-2.78) increased odds of HDP after adjustment for confounders, which was mainly due to an increased risk of gestational hypertension (OR = 1.93, 95% CI = 1.17-3.18). In addition, TgAb positivity in the first trimester was associated with a higher risk of HDP (OR = 1.78, 95% CI = 1.16-2.73) after adjustment for confounders, which was mainly due to an increased risk of gestational hypertension (OR = 1.89, 95% CI = 1.15-3.11). These associations were also seen among euthyroid women. Women with positive TPOAb in the second trimester seemed to have a higher risk of gestational hypertension (OR = 1.87, 95% CI = 1.02-3.43) after adjustment for confounders. However, among euthyroid women, TPOAb positivity in the second trimester was not associated with HDP. The TgAb status in the second trimester was not associated with HDP. CONCLUSIONS: Our results show that TPOAb positivity and TgAb positivity in the first trimester are associated with an increased risk of HDP. These data demonstrate that these associations are even seen among euthyroid women.


Assuntos
Hipertensão Induzida pela Gravidez/imunologia , Glândula Tireoide/imunologia , Adulto , Estudos de Coortes , Feminino , Humanos , Gravidez , Primeiro Trimestre da Gravidez , Segundo Trimestre da Gravidez , Estudos Prospectivos , Adulto Jovem
15.
Environ Res ; 160: 239-246, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29028488

RESUMO

OBJECTIVE: There is concern over the potential placental effects of prenatal phthalate exposure, and the potential adverse effects of prenatal phthalate exposure require further study; however, few data are available in humans. We investigated the associations between phthalate exposure in each trimester and both placental size and shape at birth. METHODS: We measured the urinary concentrations of phthalate metabolites among 2725 pregnant women in the Ma'anshan Birth Cohort. Before collecting urine samples from each of the three trimesters, the pregnant women were interviewed via questionnaires. Placental information was obtained from hospital records. We estimated the sex-specific associations between urinary phthalate concentrations in each trimester and both placental size and shape at birth using adjusted multiple regression. A linear mixed model was used for the repeated measures analysis with subject-specific random intercepts and slopes for gestational age at sample collection to test the effect of phthalate levels on placental size and shape and to estimate the effect sizes. RESULTS: Overall, placental breadth increased by 0.148cm (95% CI: 0.078, 0.218) with each 1 ln-concentration increase in MBP in the first trimester. The difference between placental length and breadth (length-breadth) decreased by 0.086cm (95% CI: -0.159, -0.012) and 0.149cm (95% CI: -0.221, -0.076) with each 1 ln-concentration increase in MMP and MBP, respectively, in the first trimester. In the second trimester, placental thickness increased by 0.017cm (95% CI: 0.006, 0.027), 0.020cm (95% CI: 0.004, 0.036), 0.028cm (95% CI: 0.007, 0.048), and 0.035cm (95% CI: 0.018, 0.053) with each 1 ln-concentration increase in MMP, MBP, MEOHP, and MEHHP, respectively. In the third trimester, placental thickness increased by 0.037cm (95% CI: 0.019, 0.056) and 0.019cm (95% CI: 0, 0.037) with each 1 ln-concentration increase in MBP and MEHP, respectively. Multiple linear regression for each offspring sex indicated that prenatal phthalate exposure increased placental thickness in both the first and second trimesters in males, whereas the corresponding relationship was close to null in females. Linear mixed models (LMMs) yielded similar results. CONCLUSION: Our results suggest the presence of associations between prenatal phthalate exposure and placental size and shape. Exposure to certain phthalates may cause the placenta to become thicker and more circular. Associations appeared stronger for the subsample representing male offspring than those for the subsample representing female offspring. Given the few studies on this topic, additional research is warranted.


Assuntos
Exposição Materna/efeitos adversos , Ácidos Ftálicos/efeitos adversos , Placenta/efeitos dos fármacos , Adolescente , Adulto , Estudos de Coortes , Feminino , Humanos , Recém-Nascido , Masculino , Ácidos Ftálicos/urina , Placenta/patologia , Gravidez , Adulto Jovem
16.
PLoS Genet ; 11(7): e1005346, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26131719

RESUMO

In vertebrate definitive hematopoiesis, nascent hematopoietic stem/progenitor cells (HSPCs) migrate to and reside in proliferative hematopoietic microenvironment for transitory expansion. In this process, well-established DNA damage response pathways are vital to resolve the replication stress, which is deleterious for genome stability and cell survival. However, the detailed mechanism on the response and repair of the replication stress-induced DNA damage during hematopoietic progenitor expansion remains elusive. Here we report that a novel zebrafish mutantcas003 with nonsense mutation in topbp1 gene encoding topoisomerase II ß binding protein 1 (TopBP1) exhibits severe definitive hematopoiesis failure. Homozygous topbp1cas003 mutants manifest reduced number of HSPCs during definitive hematopoietic cell expansion, without affecting the formation and migration of HSPCs. Moreover, HSPCs in the caudal hematopoietic tissue (an equivalent of the fetal liver in mammals) in topbp1cas003 mutant embryos are more sensitive to hydroxyurea (HU) treatment. Mechanistically, subcellular mislocalization of TopBP1cas003 protein results in ATR/Chk1 activation failure and DNA damage accumulation in HSPCs, and eventually induces the p53-dependent apoptosis of HSPCs. Collectively, this study demonstrates a novel and vital role of TopBP1 in the maintenance of HSPCs genome integrity and survival during hematopoietic progenitor expansion.


Assuntos
Proteínas de Transporte/genética , Sobrevivência Celular/genética , Reparo do DNA/genética , Hematopoese/genética , Células-Tronco Hematopoéticas/citologia , Proteínas de Peixe-Zebra/genética , Animais , Apoptose/fisiologia , Proteínas Mutadas de Ataxia Telangiectasia , Proteínas de Transporte/metabolismo , Movimento Celular/genética , Proliferação de Células , Quinase 1 do Ponto de Checagem , Códon sem Sentido/genética , Dano ao DNA/genética , Replicação do DNA/genética , DNA Topoisomerases Tipo II/metabolismo , Proteínas de Ligação a DNA/metabolismo , Embrião não Mamífero/metabolismo , Ativação Enzimática/genética , Células-Tronco Hematopoéticas/metabolismo , Hidroxiureia/farmacologia , Proteínas Quinases/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Peixe-Zebra , Proteínas de Peixe-Zebra/metabolismo
17.
Wei Sheng Yan Jiu ; 45(2): 205-10, 2016 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-27301215

RESUMO

OBJECTIVE: To evaluate the associations between pregnancy body mass index (B MI), gestational weight gain (GWG) and the risk for hypertensive disorder complicating pregnancy (HDCP). Methods In this prospective cohort study, subjects who had their first prenatal examination (gestational age ≤ 14 weeks) at Ma'anshan Maternal and Child Health Care Center were recruited under informed consent, from May 16, 2013 to September 11, 2014. All the information were collected through questionnaires, height, weight and maternal blood pressure were measured, and urine protein was detected in the first, second, and third trimester of pregnancy. RESULTS: The incidence of HDCP was 6.09% (196/3219), and preeclampsia was 1.77% (57/3219). After adjusting confounding factors, results in Logistic regression analysis showed that prepregnancy overweight and obesity, weight gain more than recommended during pregnancy were the risk factor of HDCP, the adjusted odds ratios (95% CI) were 2.33 (1.56 - 3.47), 7.85 (4.65 - 13.24) and 1.86 (1.24 - 2.79), respectively. CONCLUSION: Prepregnancy overweight, obeisity, weight gain more than recommended during pregnancy were associated with increased risk of HDCP.


Assuntos
Índice de Massa Corporal , Hipertensão Induzida pela Gravidez/epidemiologia , Aumento de Peso , Pressão Sanguínea , Peso Corporal , Feminino , Humanos , Obesidade/epidemiologia , Razão de Chances , Sobrepeso/epidemiologia , Pré-Eclâmpsia/epidemiologia , Gravidez , Estudos Prospectivos , Fatores de Risco
18.
Dev Biol ; 392(2): 233-44, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24892953

RESUMO

As the primary driving forces of gastrulation, convergence and extension (C&E) movements lead to a medio-lateral narrowing and an anterior-posterior elongation of the embryonic body axis. Histone methylation as a post-translational modification plays a critical role in early embryonic development, but its functions in C&E movements remain largely unknown. Here, we show that the setdb2-dvr1 transcriptional cascade plays a critical role in C&E movements during zebrafish gastrulation. Knockdown of Setdb2, a SET domain-containing protein possessing a potential histone H3K9 methyltransferase activity, induced abnormal C&E movements, resulting in anterior-posterior shortening and medio-lateral expansion of the embryonic axis, as well as abnormal notochord cell polarity. Furthermore, we found that Setdb2 functions through fine-tuning the expression of dvr1, a ligand of the TGF-ß superfamily, to an appropriate level to ensure proper C&E movements in a non-cell-autonomous manner. In addition, both overexpression and knockdown of Dvr1 at the one-cell stage resulted in defects at epiboly and C&E. These data demonstrate that Setdb2 is a novel regulator for C&E movements and acts by modulating the expression level of dvr1, suggesting that Dvr1 acts as a direct and essential mediator for C&E cell movements.


Assuntos
Movimento Celular/fisiologia , Gastrulação/fisiologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Histona-Lisina N-Metiltransferase/fisiologia , Fator de Crescimento Transformador beta/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/fisiologia , Peixe-Zebra/embriologia , Animais , Western Blotting , Imunofluorescência , Técnicas de Silenciamento de Genes , Histona Metiltransferases , Histona-Lisina N-Metiltransferase/metabolismo , Hibridização In Situ , Análise em Microsséries , Morfolinos/genética , Reação em Cadeia da Polimerase em Tempo Real , Fator de Crescimento Transformador beta/genética , Proteínas de Peixe-Zebra/genética
19.
Nat Chem Biol ; 9(9): 579-85, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23892894

RESUMO

The Wnt/ß-catenin signaling pathway has a crucial role in embryonic development, stem cell maintenance and human disease. By screening a synthetic chemical library of lycorine derivatives, we identified 4-ethyl-5-methyl-5,6-dihydro-[1,3]dioxolo[4,5-j]phenanthridine (HLY78) as an activator of the Wnt/ß-catenin signaling pathway, which acts in a Wnt ligand-dependent manner. HLY78 targets the DIX domain of Axin and potentiates the Axin-LRP6 association, thus promoting LRP6 phosphorylation and Wnt signaling transduction. Moreover, we identified the critical residues on Axin for HLY78 binding and showed that HLY78 may weaken the autoinhibition of Axin. In addition, HLY78 acts synergistically with Wnt in the embryonic development of zebrafish and increases the expression of the conserved hematopoietic stem cell (HSC) markers, runx1 and cmyb, in zebrafish embryos. Collectively, our study not only provides new insights into the regulation of the Wnt/ß-catenin signaling pathway by a Wnt-specific small molecule but also will facilitate therapeutic applications, such as HSC expansion.


Assuntos
Proteína Axina/metabolismo , Benzodioxóis/farmacologia , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Proteína-6 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Fenantridinas/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Proteínas Wnt/metabolismo , Via de Sinalização Wnt/efeitos dos fármacos , Animais , Proteína Axina/antagonistas & inibidores , Proteína Axina/química , Benzodioxóis/química , Células HEK293 , Humanos , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/química , Proteína-6 Relacionada a Receptor de Lipoproteína de Baixa Densidade/química , Fenantridinas/química , Ligação Proteica/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/química , Peixe-Zebra/embriologia , Peixe-Zebra/metabolismo
20.
J Obstet Gynaecol Res ; 41(8): 1214-22, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25913643

RESUMO

AIM: The aim of this study was to identify the incidence and risk factors of bacterial vaginosis among pregnant women. MATERIAL AND METHODS: Prospective data from a cohort of 668 pregnant women were used to identify potential risk factors for bacterial vaginosis during pregnancy by Cox proportional hazards regression. RESULTS: A total of 204 incident cases of bacterial vaginosis were diagnosed in 274.8 woman-years of follow-up. The bacterial vaginosis incidence rate was 0.74 per 1 woman-year and median prevalence during follow-up was 15.6%. In the adjusted model, changing underwear nearly everyday, miscarriage history, urinary tract infection during follow-up, husbands' education level, and concurrent trichomoniasis and candidiasis remained significantly associated with bacterial vaginosis (adjusted hazard ratio and 95% confidence interval were 1.87 [1.26-2.77]; 2.96 [1.96-4.47]; 2.41 [1.05-5.49]; 0.50 [0.32-0.77]; 1.82 [1.02-3.25]; 1.88 [1.30-2.70], respectively). CONCLUSION: Bacterial vaginosis during pregnancy can be affected by many factors, and some are indirectly acting factors. Further prospective studies that include a larger sample size and more information on the development of bacterial vaginosis are needed.


Assuntos
Complicações Infecciosas na Gravidez/epidemiologia , Vaginose Bacteriana/epidemiologia , Adulto , China/epidemiologia , Feminino , Humanos , Incidência , Gravidez , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco , Vaginose Bacteriana/etiologia
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