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1.
Cell ; 153(6): 1266-80, 2013 Jun 06.
Article in English | MEDLINE | ID: mdl-23727112

ABSTRACT

The DNA damage response (DDR) protein 53BP1 protects DNA ends from excessive resection in G1, and thereby favors repair by nonhomologous end-joining (NHEJ) as opposed to homologous recombination (HR). During S phase, BRCA1 antagonizes 53BP1 to promote HR. The pro-NHEJ and antirecombinase functions of 53BP1 are mediated in part by RIF1, the only known factor that requires 53BP1 phosphorylation for its recruitment to double-strand breaks (DSBs). Here, we show that a 53BP1 phosphomutant, 53BP18A, comprising alanine substitutions of the eight most N-terminal S/TQ phosphorylation sites, mimics 53BP1 deficiency by restoring genome stability in BRCA1-deficient cells yet behaves like wild-type 53BP1 with respect to immunoglobulin class switch recombination (CSR). 53BP18A recruits RIF1 but fails to recruit the DDR protein PTIP to DSBs, and disruption of PTIP phenocopies 53BP18A. We conclude that 53BP1 promotes productive CSR and suppresses mutagenic DNA repair through distinct phosphodependent interactions with RIF1 and PTIP.


Subject(s)
Carrier Proteins/metabolism , Chromosomal Proteins, Non-Histone/metabolism , DNA End-Joining Repair , DNA-Binding Proteins/metabolism , Immunoglobulin Class Switching , Nuclear Proteins/metabolism , Telomere-Binding Proteins/metabolism , Animals , B-Lymphocytes/metabolism , BRCA1 Protein/metabolism , Chromosomal Proteins, Non-Histone/genetics , DNA Breaks, Double-Stranded , DNA-Binding Proteins/genetics , Embryo, Mammalian/cytology , Embryo, Mammalian/metabolism , Fibroblasts/metabolism , Genomic Instability , Mice , Mutation , Tumor Suppressor p53-Binding Protein 1
2.
J Biol Chem ; 299(9): 105124, 2023 09.
Article in English | MEDLINE | ID: mdl-37536629

ABSTRACT

Coactivator-associated arginine methyltransferase 1 (CARM1) is an arginine methyltransferase that posttranslationally modifies proteins that regulate multiple levels of RNA production and processing. Its substrates include histones, transcription factors, coregulators of transcription, and splicing factors. CARM1 is overexpressed in many different cancer types, and often promotes transcription factor programs that are co-opted as drivers of the transformed cell state, a process known as transcription factor addiction. Targeting these oncogenic transcription factor pathways is difficult but could be addressed by removing the activity of the key coactivators on which they rely. CARM1 is ubiquitously expressed, and its KO is less detrimental in embryonic development than deletion of the arginine methyltransferases protein arginine methyltransferase 1 and protein arginine methyltransferase 5, suggesting that therapeutic targeting of CARM1 may be well tolerated. Here, we will summarize the normal in vivo functions of CARM1 that have been gleaned from mouse studies, expand on the transcriptional pathways that are regulated by CARM1, and finally highlight recent studies that have identified oncogenic properties of CARM1 in different biological settings. This review is meant to kindle an interest in the development of human drug therapies targeting CARM1, as there are currently no CARM1 inhibitors available for use in clinical trials.


Subject(s)
Neoplasms , Protein-Arginine N-Methyltransferases , Animals , Humans , Mice , Drug Delivery Systems , Neoplasms/drug therapy , Neoplasms/genetics , Transcription Factors/metabolism , Protein-Arginine N-Methyltransferases/antagonists & inhibitors , Protein-Arginine N-Methyltransferases/genetics , Protein-Arginine N-Methyltransferases/metabolism
3.
Nature ; 554(7693): 528-532, 2018 02 22.
Article in English | MEDLINE | ID: mdl-29443967

ABSTRACT

Peptidoglycan is the main component of the bacterial wall and protects cells from the mechanical stress that results from high intracellular turgor. Peptidoglycan biosynthesis is very similar in all bacteria; bacterial shapes are therefore mainly determined by the spatial and temporal regulation of peptidoglycan synthesis rather than by the chemical composition of peptidoglycan. The form of rod-shaped bacteria, such as Bacillus subtilis or Escherichia coli, is generated by the action of two peptidoglycan synthesis machineries that act at the septum and at the lateral wall in processes coordinated by the cytoskeletal proteins FtsZ and MreB, respectively. The tubulin homologue FtsZ is the first protein recruited to the division site, where it assembles in filaments-forming the Z ring-that undergo treadmilling and recruit later divisome proteins. The rate of treadmilling in B. subtilis controls the rates of both peptidoglycan synthesis and cell division. The actin homologue MreB forms discrete patches that move circumferentially around the cell in tracks perpendicular to the long axis of the cell, and organize the insertion of new cell wall during elongation. Cocci such as Staphylococcus aureus possess only one type of peptidoglycan synthesis machinery, which is diverted from the cell periphery to the septum in preparation for division. The molecular cue that coordinates this transition has remained elusive. Here we investigate the localization of S. aureus peptidoglycan biosynthesis proteins and show that the recruitment of the putative lipid II flippase MurJ to the septum, by the DivIB-DivIC-FtsL complex, drives peptidoglycan incorporation to the midcell. MurJ recruitment corresponds to a turning point in cytokinesis, which is slow and dependent on FtsZ treadmilling before MurJ arrival but becomes faster and independent of FtsZ treadmilling after peptidoglycan synthesis activity is directed to the septum, where it provides additional force for cell envelope constriction.


Subject(s)
Cytokinesis , Peptidoglycan/biosynthesis , Phospholipid Transfer Proteins/metabolism , Staphylococcus aureus/cytology , Staphylococcus aureus/metabolism , Bacterial Proteins/metabolism , Cell Wall/chemistry , Cell Wall/metabolism , Cytoskeletal Proteins/metabolism , Kinetics , Microscopy, Fluorescence , Pyridines/pharmacology , Single-Cell Analysis , Staphylococcus aureus/drug effects , Thiazoles/pharmacology , Uridine Diphosphate N-Acetylmuramic Acid/analogs & derivatives , Uridine Diphosphate N-Acetylmuramic Acid/metabolism
4.
Genes Dev ; 30(2): 149-63, 2016 Jan 15.
Article in English | MEDLINE | ID: mdl-26744420

ABSTRACT

Class switch recombination (CSR) diversifies antibodies for productive immune responses while maintaining stability of the B-cell genome. Transcription at the immunoglobulin heavy chain (Igh) locus targets CSR-associated DNA damage and is promoted by the BRCT domain-containing PTIP (Pax transactivation domain-interacting protein). Although PTIP is a unique component of the mixed-lineage leukemia 3 (MLL3)/MLL4 chromatin-modifying complex, the mechanisms for how PTIP promotes transcription remain unclear. Here we dissected the minimal structural requirements of PTIP and its different protein complexes using quantitative proteomics in primary lymphocytes. We found that PTIP functions in transcription and CSR separately from its association with the MLL3/MLL4 complex and from its localization to sites of DNA damage. We identified a tandem BRCT domain of PTIP that is sufficient for CSR and identified PA1 as its main functional protein partner. Collectively, we provide genetic and biochemical evidence that a PTIP-PA1 subcomplex functions independently from the MLL3/MLL4 complex to mediate transcription during CSR. These results further our understanding of how multifunctional chromatin-modifying complexes are organized by subcomplexes that harbor unique and distinct activities.


Subject(s)
Carrier Proteins/metabolism , Histone-Lysine N-Methyltransferase/metabolism , Immunoglobulin Class Switching/genetics , Immunoglobulin Heavy Chains/genetics , Immunoglobulin Heavy Chains/immunology , Nuclear Proteins/metabolism , DNA Damage , DNA-Binding Proteins , Gene Expression Regulation/immunology , Molecular Structure , Protein Structure, Tertiary , Protein Transport
5.
J Biol Chem ; 298(3): 101588, 2022 03.
Article in English | MEDLINE | ID: mdl-35033534

ABSTRACT

The methyl-lysine readers plant homeodomain finger protein 20 (PHF20) and its homolog PHF20-like protein 1 (PHF20L1) are known components of the nonspecific lethal (NSL) complex that regulates gene expression through its histone acetyltransferase activity. In the current model, both PHF homologs coexist in the same NSL complex, although this was not formally tested; nor have the functions of PHF20 and PHF20L1 regarding NSL complex integrity and transcriptional regulation been investigated. Here, we perform an in-depth biochemical and functional characterization of PHF20 and PHF20L1 in the context of the NSL complex. Using mass spectrometry, genome-wide chromatin analysis, and protein-domain mapping, we identify the existence of two distinct NSL complexes that exclusively contain either PHF20 or PHF20L1. We show that the C-terminal domains of PHF20 and PHF20L1 are essential for complex formation with NSL, and the Tudor 2 domains are required for chromatin binding. The genome-wide chromatin landscape of PHF20-PHF20L1 shows that these proteins bind mostly to the same genomic regions, at promoters of highly expressed/housekeeping genes. Yet, deletion of PHF20 and PHF20L1 does not abrogate gene expression or impact the recruitment of the NSL complex to those target gene promoters, suggesting the existence of an alternative mechanism that compensates for the transcription of genes whose sustained expression is important for critical cellular functions. This work shifts the current paradigm and lays the foundation for studies on the differential roles of PHF20 and PHF20L1 in regulating NSL complex activity in physiological and diseases states.


Subject(s)
Chromosomal Proteins, Non-Histone , DNA-Binding Proteins , Homeodomain Proteins , Lysine , Transcription Factors , Acetylation , Chromatin/genetics , Chromosomal Proteins, Non-Histone/genetics , Chromosomal Proteins, Non-Histone/metabolism , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Gene Expression Regulation , Histone-Lysine N-Methyltransferase/genetics , Histone-Lysine N-Methyltransferase/metabolism , Histones/genetics , Histones/metabolism , Homeodomain Proteins/genetics , Homeodomain Proteins/metabolism , Lysine/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism
6.
Cytokine ; 166: 156189, 2023 06.
Article in English | MEDLINE | ID: mdl-37004469

ABSTRACT

Controlling systemic proinflammatory and prooxidant effectors is essential for mitigating cardiovascular risk and mortality in patients with end-stage renal disease (ESRD). However, monitoring these processes is still challenging due to the high uncertainty about their determinants and predictors. Thus, we investigated the relationship between advanced glycosylation end products (AGE), proinflammatory and prooxidant effectors in ESRD patients undergoing hemodialysis (HD). In addition to nutritional profile and dialysis efficiency, AGE, cytokines, chemokines, C-reactive protein (CRP), total (TAC) and non-protein (npAC) antioxidant capacity, lipid and protein oxidation were analyzed in blood samples from 43 HD patients. AGE, CRP, cytokines, chemokines, protein carbonyl (PCn), and malondialdehyde (MDA) were upregulated, while TAC and npAC were down-regulated in HD patients compared to heath subjects. Dialysis efficiency, TAC and npAC were reduced, while leucocytes counting, pre- and post-HD urea, TNF, IL-6, IL-10, CCL-2, MIP-1ß, PCn, and MDA were increased in patients with higher AGE accumulation compared to those with lower AGE levels. Serum levels of CRP, protein carbonyl, malondialdehyde, and all cytokines and chemokines analyzed were correlated with AGE circulating levels for patients with higher AGE accumulation. AGE was inversely correlated with IL-10, TAC and npAC in patients with higher AGE accumulation. AGE exhibited predictive value (determination coefficient) to explain CRP, cytokines, chemokines, PCN, MDA, TAC and npAC variability in patients with higher AGE levels. Taken together, our findings provide evidence that AGE accumulation is associated with important proinflammatory and prooxidant effectors in patients with ESRD undergoing hemodialysis. Thus, AGE monitoring may be relevant to predict systemic inflammatory stress and the balance between oxidant and antioxidant status in these patients.


Subject(s)
Interleukin-10 , Kidney Failure, Chronic , Humans , Interleukin-10/metabolism , Antioxidants/metabolism , Reactive Oxygen Species , Glycosylation , Oxidative Stress , Renal Dialysis/adverse effects , C-Reactive Protein/metabolism , Cytokines/metabolism , Glycation End Products, Advanced/metabolism , Malondialdehyde
7.
Reprod Biol Endocrinol ; 21(1): 31, 2023 Mar 27.
Article in English | MEDLINE | ID: mdl-36973721

ABSTRACT

BACKGROUND: The predictive capability of time-lapse monitoring (TLM) selection algorithms is influenced by patient characteristics, type and quality of data included in the analysis and the used statistical methods. Previous studies excluded DET cycles of which only one embryo implanted, introducing bias into the data. Therefore, we wanted to develop a TLM prediction model that is able to predict pregnancy chances after both single- and double embryo transfer (SET and DET). METHODS: This is a retrospective study of couples (n = 1770) undergoing an in vitro fertilization cycle at the Erasmus MC, University Medical Centre Rotterdam (clinic A) or the Reinier de Graaf Hospital (clinic B). This resulted in 2058 transferred embryos with time-lapse and pregnancy outcome information. For each dataset a prediction model was established by using the Embryo-Uterus statistical model with the number of gestational sacs as the outcome variable. This process was followed by cross-validation. RESULTS: Prediction model A (based on data of clinic A) included female age, t3-t2 and t5-t4, and model B (clinic B) included female age, t2, t3-t2 and t5-t4. Internal validation showed overfitting of model A (calibration slope 0.765 and area under the curve (AUC) 0.60), and minor overfitting of model B (slope 0.915 and AUC 0.65). External validation showed that model A was capable of predicting pregnancy in the dataset of clinic B with an AUC of 0.65 (95% CI: 0.61-0.69; slope 1.223, 95% CI: 0.903-1.561). Model B was less accurate in predicting pregnancy in the dataset of clinic A (AUC 0.60, 95% CI: 0.56-0.65; slope 0.671, 95% CI: 0.422-0.939). CONCLUSION: Our study demonstrates a novel approach to the development of a TLM prediction model by applying the EU statistical model. With further development and validation in clinical practice, our prediction model approach can aid in embryo selection and decision making for SET or DET.


Subject(s)
Fertilization in Vitro , Pregnancy Outcome , Pregnancy , Humans , Female , Child, Preschool , Retrospective Studies , Pregnancy Rate , Models, Statistical , Uterus
8.
Gynecol Oncol ; 176: 76-81, 2023 09.
Article in English | MEDLINE | ID: mdl-37478615

ABSTRACT

OBJECTIVE: To analyze the expression and prognostic role of L1CAM in tubo-ovarian high-grade serous carcinoma (HGSC). METHODS: L1CAM protein expression by immunohistochemistry was analyzed in 644 HGSC (413 effusions, 231 surgical specimens). Expression was analyzed for association with clinicopathologic parameters and survival. RESULTS: L1CAM protein expression was found in 401/413 (97%) effusions and 209/231 (90%) surgical specimens, with significantly higher staining extent in effusions (p < 0.001). L1CAM protein expression in effusions was unrelated to clinicopathologic parameters (p > 0.05). In surgical specimens, higher L1CAM expression was significantly related to primary (intrinsic) chemoresistance (p = 0.017). High (>25%) L1CAM expression in HGSC effusions (p = 0.02), older patient age (p = 0.013), FIGO stage IV disease (p < 0.001) and larger residual disease volume (p = 0.001) were significantly associated with shorter overall survival (OS) in univariate analysis. In Cox multivariate analysis, only FIGO stage (p = 0.001) and residual disease volume (p = 0.003) were independent prognosticators of OS. L1CAM expression in effusions was unrelated to progression-free survival (PFS). There was no association between L1CAM expression in surgical specimens and survival. CONCLUSION: L1CAM is overexpressed in HGSC effusions compared to surgical specimens. Its overexpression in effusions is significantly associated with shorter OS, but not independently of established prognostic factors such as FIGO stage and residual disease volume.


Subject(s)
Cystadenocarcinoma, Serous , Neural Cell Adhesion Molecule L1 , Ovarian Neoplasms , Female , Humans , Biomarkers, Tumor/metabolism , Clinical Relevance , Prognosis
9.
J Perianesth Nurs ; 2023 Nov 16.
Article in English | MEDLINE | ID: mdl-37978973

ABSTRACT

PURPOSE: To explore the experiences of uncertainty in the clinical reasoning of nurses in the postanesthesia care unit (PACU). DESIGN: A phenomenological descriptive design, following Colaizzi's analysis. METHODS: Semistructured interviews were conducted with 14 nurses from a PACU on their experience of uncertainty in clinical reasoning. The interviews were digitally audio-recorded and transcribed verbatim. Two researchers conducted data analysis independently and followed seven phases: (re)reading the transcripts, extracting significant statements, formulating meanings from significant statements, aggregating formulated meanings into themes, developing a description of the phenomenon's essential structure, generating of the fundamental structure of the phenomenon, validating of the findings through participant feedback. The process employed MAXQDA analytics Pro 2022 software. Consolidated Criteria for Reporting A Qualitative Research checklist was used for reporting. FINDINGS: From uncertainty experiences in nurses' clinical reasoning, 10 themes emerged: ambiguity and decision latitude, communication, work ethic, difficulty interpreting and predicting outcomes, cognitive performance impairment, incivility, core competence vagueness of postanesthesia nurses, high-tech care, (in)security and risk, and occupational stress. CONCLUSIONS: The experiences of uncertainty in clinical reasoning of nurses in postanesthesia care units are highly focused on patient safety. Exploring these experiences has made uncertainty more tangible and explicit, which will enable nurses in postanesthesia care units to prepare for adaptive responses to deal with uncertainty when it occurs in clinical practice.

10.
Curr Psychol ; : 1-18, 2023 Mar 25.
Article in English | MEDLINE | ID: mdl-37359592

ABSTRACT

This research aimed to explore the direct and indirect effects of students' school engagement, school climate and parenting practices on youth's externalizing behaviors. A quantitative methodology with a sample of 183 Portuguese students, aged between 11 and 16 years old, was used. The main results suggested negative associations between externalizing behaviors and higher levels of school engagement and positive school climate. Poor parental supervision, inconsistent discipline and corporal punishment were positively related with externalizing behaviors, contrary to parental involvement and positive parenting that were associated with lower levels of externalizing behaviors. However, negative parenting practices were associated with lower levels of school engagement. Additionally, the results indicated that parenting practices might influence youth's externalizing behaviors through school engagement.

11.
Scand J Caring Sci ; 36(2): 493-503, 2022 Jun.
Article in English | MEDLINE | ID: mdl-34761406

ABSTRACT

BACKGROUND: Perioperative experience can be very distressing in adolescence if not managed properly by healthcare professionals. In the clinical context, the emotional expression of the adolescent is less spontaneous, which makes the assessment of anxiety, pain or even the desire to be involved in the perioperative process, difficult. Listening to their perioperative experiences will permit an understanding of their difficulties and expectations, regardless of the surgical intervention undergone. AIM: To explore the adolescents' perioperative experiences in relation to inpatient and outpatient elective surgery. METHODS: Qualitative exploratory study, with thematic analysis approach. A purposive sample of 40 adolescents aged 14-18 years and in the perioperative period, from two paediatric surgery settings in a university hospital, was questioned from January to July 2020. Data were collected using a semi-structured interview and analysed inductively with qualitative thematic analysis. RESULTS: The data yielded one major theme, five themes, and 14 sub-themes. The major theme, Adolescent in perioperative period, included the five themes: (1) emotional and psychological aspects; (2) physical aspects; (3) social aspects; (4) organizational aspects; (5) previous surgical experience. Adolescents expressed fear of the unknown, anxiety, difficulty in pain control, and feelings of autonomy loss. Issues related to withdrawal from school and friends is also a focus of adolescent concern during the perioperative period. Despite showing satisfaction with the way they were cared for, they complained about the lack of pre- and post-operative preparation. CONCLUSION: There are aspects that should be considered when caring for adolescents in perioperative period. As far as possible, programmes to prevent adolescents' anxiety in perioperative period should be designed in a holistic perspective, with aim at the psychological, physical, sociocultural, and organisational aspects.


Subject(s)
Inpatients , Outpatients , Adolescent , Child , Emotions , Humans , Pain , Qualitative Research
12.
J Perianesth Nurs ; 37(4): 458-466, 2022 08.
Article in English | MEDLINE | ID: mdl-35400552

ABSTRACT

PURPOSE: To describe the nurses' views for consideration when designing a program to prevent adolescents' anxiety in the perioperative period. DESIGN: A qualitative descriptive case study using focus group and thematic analysis was conducted. METHODS: Three face-to-face focus group interviews were conducted in October and November 2019 in the pediatric department of a university hospital. A purposive criterion method was applied to achieve a sample of 19 pediatric nurse specialists. Data were organized and systematized in the professional software for qualitative and mixed methods data analysis software (MAXQDA) and treated through the thematic analysis method. The COREQ checklist was used to report data collection, analysis, and results. FINDINGS: Four major themes and 14 subthemes regarding the perioperative period were generated. The first, adolescent evaluation, included the knowledge evaluation about procedures, signs and symptoms, and desire to be engaged in care. The second, caring adolescents and parents, means that nurses must be ready to care for both, use the opportunities to implement the nursing interventions, and manage physical teen space to accommodate adolescents in the ward. The third, nurses' challenges in the perioperative period, comprise the lack of time and trained nurses to work with adolescents, and the absence of prior adolescents' preparation and postoperative feedback. The fourth, nursing consultation, consists in promoting interdisciplinarity, developing the nursing interventions, and the main content to be included in the program's design. CONCLUSIONS: Given the challenges experienced by nurses when caring for adolescents in the perioperative period, nurses suggested a systematized assessment of the adolescent at an early stage of the perioperative caring process. Added to this is the nurse's readiness for the adolescent and parents, as well as the existence of trained nurses to evaluate adolescents and to implement non-pharmacological interventions in the perioperative period. A nursing consultation emerges as the most suitable solution to include in a program to prepare adolescents for the surgical procedure and help them to manage anxiety. This kind of intervention should begin in the preoperative period, preferably after the decision on the need for the procedure.


Subject(s)
Nurses , Nursing Care , Adolescent , Anxiety/prevention & control , Child , Humans , Perioperative Period , Qualitative Research
13.
Radiology ; 299(3): 715-724, 2021 06.
Article in English | MEDLINE | ID: mdl-33825512

ABSTRACT

Background In patients with liver cancer, portal vein embolization (PVE) is recommended to promote liver growth before major hepatectomies. However, the optimal embolization strategy has not been established. Purpose To compare liver regeneration as seen at CT in participants with liver cancer, before major hepatectomies, with N-butyl-cyanoacrylate (NBCA) plus iodized oil versus standard polyvinyl alcohol (PVA) particles plus coils, for PVE. Materials and Methods In this single-center, prospective, randomized controlled trial (Best Future Liver Remnant, or BestFLR, trial; International Standard Randomized Controlled Trial Number 16062796), PVE with NBCA plus iodized oil was compared with standard PVE with PVA particles plus coils in participants with liver cancer. Participant recruitment started in November 2017 and ended in March 2020. Participants were randomly assigned to undergo PVE with PVA particles plus coils or PVE with NBCA plus iodized oil. The primary end point was liver growth assessed with CT 14 days and 28 days after PVE. Secondary outcomes included posthepatectomy liver failure, surgical complications, and length of intensive care treatment and hospital stay. The Mann-Whitney U test was used to compare continuous outcomes according to PVE material, whereas the Χ2 test or Fisher exact test was used for categoric variables. Results Sixty participants (mean age, 61 years ± 11 [standard deviation]; 32 men) were assigned to the PVA particles plus coils group (n = 30) or to the NBCA plus iodized oil group (n = 30). Interim analysis revealed faster and superior liver hypertrophy for the NBCA plus iodized oil group versus the PVA particles plus coils group 14 days and 28 days after PVE (absolute hypertrophy of 46% vs 30% [P < .001] and 57% vs 37% [P < .001], respectively). Liver growth for the proposed hepatectomy was achieved in 87% of participants (26 of 30) in the NBCA plus iodized oil group versus 53% of participants (16 of 30) in the PVA particles plus coils group (P = .008) 14 days after PVE. Liver failure occurred in 13% of participants (three of 24) in the NBCA plus iodized oil group and in 27% of participants (six of 22) in the PVA particles plus coils group (P = .27). Conclusion Portal vein embolization with N-butyl-cyanoacrylate plus iodized oil produced greater and faster liver growth as seen at CT in participants with liver cancer, compared with portal vein embolization with polyvinyl alcohol particles plus coils, allowing for earlier surgical intervention. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Arellano in this issue.


Subject(s)
Embolization, Therapeutic/methods , Liver Neoplasms/diagnostic imaging , Liver Neoplasms/therapy , Liver Regeneration , Tomography, X-Ray Computed , Combined Modality Therapy , Enbucrilate , Female , Hepatectomy , Humans , Iodized Oil , Male , Middle Aged , Polyvinyl Alcohol , Portal Vein , Prospective Studies
14.
Proc Natl Acad Sci U S A ; 115(43): E10137-E10146, 2018 10 23.
Article in English | MEDLINE | ID: mdl-30297393

ABSTRACT

The bone is essential for locomotion, calcium storage, and harboring the hematopoietic stem cells (HSCs) that supply the body with mature blood cells throughout life. HSCs reside at the interface of the bone and bone marrow (BM), where active bone remodeling takes place. Although the cellular components of the BM niche have been characterized, little is known about its epigenetic regulation. Here we find that the histone methylation regulator PTIP (Pax interaction with transcription-activation domain protein-1) is required to maintain the integrity of the BM niche by promoting osteoclast differentiation. PTIP directly promotes chromatin changes required for the expression of Pparγ (peroxisome proliferator-activated receptor-γ), a transcription factor essential for osteoclastogenesis. PTIP deletion leads to a drastic reduction of HSCs in the BM and induces extramedullary hematopoiesis. Furthermore, exposure of acute myeloid leukemia cells to a PTIP-deficient BM microenvironment leads to a reduction in leukemia-initiating cells and increased survival upon transplantation. Taken together, our data identify PTIP as an epigenetic regulator of osteoclastogenesis that is required for the integrity of the BM niche to sustain both normal hematopoiesis and leukemia.


Subject(s)
Bone Marrow/metabolism , Carrier Proteins/metabolism , Histones/metabolism , Leukemia/metabolism , Nuclear Proteins/metabolism , Stem Cell Niche/physiology , Animals , Bone Marrow Cells/metabolism , Bone and Bones/metabolism , Cell Differentiation/physiology , DNA-Binding Proteins , Epigenesis, Genetic/physiology , Hematopoiesis/physiology , Hematopoietic Stem Cells/metabolism , Methylation , Mice , Osteoclasts/metabolism , Osteogenesis/physiology , PPAR gamma/metabolism
15.
Proc Natl Acad Sci U S A ; 115(10): E2311-E2319, 2018 03 06.
Article in English | MEDLINE | ID: mdl-29463696

ABSTRACT

Blood cell formation must be appropriately maintained throughout life to provide robust immune function, hemostasis, and oxygen delivery to tissues, and to prevent disorders that result from over- or underproduction of critical lineages. Persistent inflammation deregulates hematopoiesis by damaging hematopoietic stem and progenitor cells (HSPCs), leading to elevated myeloid cell output and eventual bone marrow failure. Nonetheless, antiinflammatory mechanisms that protect the hematopoietic system are understudied. The transcriptional regulator STAT3 has myriad roles in HSPC-derived populations and nonhematopoietic tissues, including a potent antiinflammatory function in differentiated myeloid cells. STAT3 antiinflammatory activity is facilitated by STAT3-mediated transcriptional repression of Ube2n, which encodes the E2 ubiquitin-conjugating enzyme Ubc13 involved in proinflammatory signaling. Here we demonstrate a crucial role for STAT3 antiinflammatory activity in preservation of HSPCs and lineage-balanced hematopoiesis. Conditional Stat3 removal from the hematopoietic system led to depletion of the bone marrow lineage- Sca-1+ c-Kit+ CD150+ CD48- HSPC subset (LSK CD150+ CD48- cells), myeloid-skewed hematopoiesis, and accrual of DNA damage in HSPCs. These responses were accompanied by intrinsic transcriptional alterations in HSPCs, including deregulation of inflammatory, survival and developmental pathways. Concomitant Ube2n/Ubc13 deletion from Stat3-deficient hematopoietic cells enabled lineage-balanced hematopoiesis, mitigated depletion of bone marrow LSK CD150+ CD48- cells, alleviated HSPC DNA damage, and corrected a majority of aberrant transcriptional responses. These results indicate an intrinsic protective role for STAT3 in the hematopoietic system, and suggest that this is mediated by STAT3-dependent restraint of excessive proinflammatory signaling via Ubc13 modulation.


Subject(s)
Blood Cells/immunology , Hematopoiesis , STAT3 Transcription Factor/immunology , Animals , Blood Cells/cytology , Cell Lineage , Female , Hematopoietic Stem Cells/cytology , Hematopoietic Stem Cells/immunology , Male , Mice , Mice, Inbred C57BL , Myeloid Cells/cytology , Myeloid Cells/immunology , STAT3 Transcription Factor/genetics , Ubiquitin-Conjugating Enzymes/genetics , Ubiquitin-Conjugating Enzymes/immunology
16.
Cleft Palate Craniofac J ; 58(12): 1482-1489, 2021 12.
Article in English | MEDLINE | ID: mdl-33535818

ABSTRACT

OBJECTIVE: To investigate subannular tube (SAT) placement as an alternative treatment of chronic middle ear disease in children with cleft palate. DESIGN: Retrospective cohort study. PARTICIPANTS: All children with cleft palate with intractable otitis media with effusion and/or with tympanic membrane retraction, operated for insertion of 1 or more sets of transtympanic tubes followed by SAT in a tertiary center. MAIN OUTCOME MEASURES: Audiological outcomes, average duration of tubes, and postoperative complications were analyzed. RESULTS: This study included 21 children with cleft palate, aged 3 to 14 years. A total of 38 ears was evaluated. The median time of follow-up was 42 months. During follow-up, 69.2% of the patients had no complications. Observed complications were otorrhea (13.5%) and tube obstruction (7.7%). In 7.9% of the cases, otitis media with effusion relapsed after tube extrusion. By the end of the study, 76.3% of the tubes remained in situ and 68.4% of the tympanic membranes had the SAT in place and had no significant alterations. The mean duration of SATs was 16 months, which was significantly superior to transtympanic tube duration. A significant sustained improvement in the hearing of children with SATs was observed. CONCLUSION: Subannular tube insertion results in hearing improvement to normal range and tympanic retraction pockets reversion in children with cleft palate with persistent otitis media with effusion and tympanic retraction/atelectasis. This surgery appears to be safe and provides long-term efficient middle ear aeration. Strict postoperative follow-up is crucial for the success of the treatment.


Subject(s)
Cleft Palate , Ear Diseases , Otitis Media with Effusion , Otitis Media , Child , Cleft Palate/surgery , Humans , Middle Ear Ventilation , Otitis Media with Effusion/surgery , Retrospective Studies
17.
J Trauma Nurs ; 28(3): 194-202, 2021.
Article in English | MEDLINE | ID: mdl-33949356

ABSTRACT

BACKGROUND: Hypothermia in trauma patients causes increased morbidity and mortality. Swift recognition and treatment are important to prevent any further heat loss. In addition, patient discomfort from cold decreases satisfaction with care. The administration of active and passive rewarming measures is important in the prevention and treatment of hypothermia, but their use in prehospital trauma patients in Portugal has not been previously reported. OBJECTIVE: To assess the prevalence of hypothermia, the impact of rewarming measures, and the management of the discomfort caused by cold. METHODS: This is a prospective cohort study conducted in Immediate Life Support Ambulances in Portugal between March 1, 2019, and April 30, 2020. RESULTS: This study included records of 586 trauma patients; of whom, 66.2% were men. Cranioencephalic trauma was the most common trauma observed, followed by lower limb and thoracic traumas. Mean body temperature increased 0.12 °C between the first and last assessments (p < .05). Most patients experiencing a level of discomfort of 5 or more on a 0-10 scale reported improvement (from 17.2% to 2.4% after nurses' intervention). Warmed intravenous fluids proved to be effective (p < .05) in increasing body temperature, and passive rewarming measures were effective in preventing hypothermia. CONCLUSIONS: Hypothermia management has to consider the initial temperature, the season, the available rewarming measures, and the objectives to be achieved. The optimization of resources for the monitoring and treatment of hypothermia should be a priority in prehospital assistance. The implementation of rewarming measures improves patients' outcomes and decreases the discomfort caused by cold in prehospital care.


Subject(s)
Emergency Medical Services , Hypothermia , Thoracic Injuries , Female , Humans , Hypothermia/therapy , Male , Prospective Studies , Rewarming
18.
Inorg Chem ; 59(13): 9116-9134, 2020 Jul 06.
Article in English | MEDLINE | ID: mdl-32578983

ABSTRACT

The interpretation of in vitro cytotoxicity data of Cu(II)-1,10-phenanthroline (phen) complexes normally does not take into account the speciation that complexes undergo in cell incubation media and its implications in cellular uptake and mechanisms of action. We synthesize and test the activity of several distinct Cu(II)-phen compounds; up to 24 h of incubation, the cytotoxic activity differs for the Cu complexes and the corresponding free ligands, but for longer incubation times (e.g., 72 h), all compounds display similar activity. Combining the use of several spectroscopic, spectrometric, and electrochemical techniques, the speciation of Cu-phen compounds in cell incubation media is evaluated, indicating that the originally added complex almost totally decomposed and that Cu(II) and phen are mainly bound to bovine serum albumin. Several methods are used to disclose relationships between structure, activity, speciation in incubation media, cellular uptake, distribution of Cu in cells, and cytotoxicity. Contrary to what is reported in most studies, we conclude that interaction with cell components and cell death involves the separate action of Cu ions and phen molecules, not [Cu(phen)n] species. This conclusion should similarly apply to many other Cu-ligand systems reported to date.


Subject(s)
Antineoplastic Agents/pharmacology , Coordination Complexes/pharmacology , Copper/pharmacology , Phenanthrolines/pharmacology , Animals , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/metabolism , Cattle , Cell Line, Tumor , Coordination Complexes/chemical synthesis , Coordination Complexes/metabolism , Copper/chemistry , Copper/metabolism , Drug Screening Assays, Antitumor , Humans , Ligands , Phenanthrolines/chemical synthesis , Phenanthrolines/metabolism , Protein Binding , Serum Albumin, Bovine/metabolism
19.
Nature ; 514(7520): 107-11, 2014 Oct 02.
Article in English | MEDLINE | ID: mdl-25079327

ABSTRACT

Self-renewal is the hallmark feature both of normal stem cells and cancer stem cells. Since the regenerative capacity of normal haematopoietic stem cells is limited by the accumulation of reactive oxygen species and DNA double-strand breaks, we speculated that DNA damage might also constrain leukaemic self-renewal and malignant haematopoiesis. Here we show that the histone methyl-transferase MLL4, a suppressor of B-cell lymphoma, is required for stem-cell activity and an aggressive form of acute myeloid leukaemia harbouring the MLL-AF9 oncogene. Deletion of MLL4 enhances myelopoiesis and myeloid differentiation of leukaemic blasts, which protects mice from death related to acute myeloid leukaemia. MLL4 exerts its function by regulating transcriptional programs associated with the antioxidant response. Addition of reactive oxygen species scavengers or ectopic expression of FOXO3 protects MLL4(-/-) MLL-AF9 cells from DNA damage and inhibits myeloid maturation. Similar to MLL4 deficiency, loss of ATM or BRCA1 sensitizes transformed cells to differentiation, suggesting that myeloid differentiation is promoted by loss of genome integrity. Indeed, we show that restriction-enzyme-induced double-strand breaks are sufficient to induce differentiation of MLL-AF9 blasts, which requires cyclin-dependent kinase inhibitor p21(Cip1) (Cdkn1a) activity. In summary, we have uncovered an unexpected tumour-promoting role of genome guardians in enforcing the oncogene-induced differentiation blockade in acute myeloid leukaemia.


Subject(s)
DNA Damage , Leukemia, Myeloid, Acute/enzymology , Leukemia, Myeloid, Acute/pathology , Myelopoiesis , Animals , Ataxia Telangiectasia Mutated Proteins/metabolism , BRCA1 Protein/genetics , BRCA1 Protein/metabolism , Cell Transformation, Neoplastic , Cyclin-Dependent Kinase Inhibitor p21/metabolism , DNA Breaks, Double-Stranded , DNA Repair , Female , Gene Expression Regulation, Neoplastic , Genes, BRCA1 , Hematopoietic Stem Cells/cytology , Hematopoietic Stem Cells/metabolism , Hematopoietic Stem Cells/pathology , Histone-Lysine N-Methyltransferase/deficiency , Histone-Lysine N-Methyltransferase/genetics , Histone-Lysine N-Methyltransferase/metabolism , Male , Mice , Oncogene Proteins, Fusion/genetics , Oncogene Proteins, Fusion/metabolism , Reactive Oxygen Species/metabolism
20.
BMC Pregnancy Childbirth ; 20(1): 276, 2020 May 06.
Article in English | MEDLINE | ID: mdl-32375667

ABSTRACT

BACKGROUND: Mothers' reports about pregnancy, maternity and their experiences during the perinatal period have been associated with infants' later quality of attachment and development. Yet, there has been little research with mothers of very preterm newborns. This study aimed to explore mothers' experiences related to pregnancy, premature birth, relationship with the newborn, and future perspectives, and to compare them in the context of distinct infants' at-birth-risk conditions. METHODS: A semi-structured interview was conducted with women after birth, within the first 72 h of the newborn's life. A total of 150 women participated and were divided in three groups: (1) 50 mothers of full-term newborns (Gestational Age (GA) ≥ 37 weeks; FT), (2) 50 mothers of preterm newborns (GA 32-36 weeks; PT) and (3) 50 mothers of very preterm newborns (GA < 32 weeks; VPT). RESULTS: Mothers of full-term infants responded more often that their children were calm and that they did not expect difficulties in taking care of and providing for the baby. Mothers of preterm newborns although having planned and accepted well the pregnancy (with no mixed or ambivalent feelings about it) and while being optimistic about their competence to take care of the baby, mentioned feeling frightened because of the unexpected occurrence of a premature birth and its associated risks. Mothers of very preterm newborns reported more negative and distressful feelings while showing more difficulties in anticipating the experience of caring for their babies. CONCLUSION: The results indicate that Health Care Systems and Neonatal Care Policy should provide differentiated psychological support and responses to mothers, babies and families, taking into account the newborns' GA and neonatal risk factors.


Subject(s)
Mother-Child Relations/psychology , Mothers/psychology , Adult , Female , Gestational Age , Humans , Infant, Extremely Premature , Infant, Newborn , Intensive Care Units, Neonatal , Male , Parturition/psychology , Pregnancy , Premature Birth/psychology
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