Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 277
Filter
2.
Nat Rev Cancer ; 2024 May 02.
Article in English | MEDLINE | ID: mdl-38698126

ABSTRACT

In the past two decades, technological advances have brought unprecedented insights into the paediatric cancer genome revealing characteristics distinct from those of adult cancer. Originating from developing tissues, paediatric cancers generally have low mutation burden and are driven by variants that disrupt the transcriptional activity, chromatin state, non-coding cis-regulatory regions and other biological functions. Within each tumour, there are multiple populations of cells with varying states, and the lineages of some can be tracked to their fetal origins. Genome-wide genetic screening has identified vulnerabilities associated with both the cell of origin and transcription deregulation in paediatric cancer, which have become a valuable resource for designing new therapeutic approaches including those for small molecules, immunotherapy and targeted protein degradation. In this Review, we present recent findings on these facets of paediatric cancer from a pan-cancer perspective and provide an outlook on future investigations.

3.
Am J Cardiol ; 2024 May 14.
Article in English | MEDLINE | ID: mdl-38754713
5.
World Neurosurg ; 187: 2-10, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38575063

ABSTRACT

BACKGROUND: Despite global efforts to improve surgical care access, many low- and middle-income countries, especially in neurosurgery, face significant shortages. The Gambia exemplifies this, with only 1 fully qualified neurosurgeon serving its population of 2.5 million people. This scarcity results in higher morbidity and mortality. OBJECTIVE: We aim to document the history and current state of neurosurgery in the Gambia to raise awareness and promote neurosurgery development. METHODS: The study reviews the Gambia's health care system, infrastructure, neurosurgical history, workforce, disease burden, and progress, with information derived from reference sources as well as author experience and interviews with key partners in Gambian health care. RESULTS: Neurosurgery in the Gambia began in the 1970s, facing constraints due to competing health care demands. Significant progress occurred much later in the early 2010s, marked by the initiation of Banjul Neuro Missions and the establishment of a dedicated neurosurgery unit. We report significant progress with neurosurgical interventions in the past few years showcasing the unit's dedication to advancing neurosurgical care in the Gambia. However, challenges persist, including a lack of trained neurosurgeons, equipment shortages such as ventilators and diagnostic imaging. Financial barriers for patients, particularly related to the costs of computer tomography scans, pose significant hurdles, impacting the timely diagnosis and intervention for neurological conditions. CONCLUSIONS: Neurosurgery in the Gambia is progressing, but challenges like equipment scarcity hinder further progress. We emphasize the need for addressing cost barriers, improving infrastructure, and fostering research. Engaging the government and international collaborations are vital for sustained development in Gambian neurosurgery.

6.
Am J Cardiol ; 218: 68-71, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38428710

ABSTRACT

Myocarditis and acute myocardial infarction (AMI) have been reported after COVID-19 messenger ribonucleic acid vaccination. Nearly all reported patients with myocarditis or AMI after COVID-19 vaccination have survived and become asymptomatic. Described herein is a previously healthy man who developed severe heart decompensation shortly after receiving a COVID-19 vaccination and died approximately 40 hours later. An autopsy disclosed massive AMI.


Subject(s)
COVID-19 , Myocardial Infarction , Myocarditis , Male , Humans , COVID-19 Vaccines , Coronary Vessels
7.
Vet Rec ; 194(6): 234, 2024 03 16.
Article in English | MEDLINE | ID: mdl-38488575
8.
Nature ; 628(8007): 442-449, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38538798

ABSTRACT

Whereas oncogenes can potentially be inhibited with small molecules, the loss of tumour suppressors is more common and is problematic because the tumour-suppressor proteins are no longer present to be targeted. Notable examples include SMARCB1-mutant cancers, which are highly lethal malignancies driven by the inactivation of a subunit of SWI/SNF (also known as BAF) chromatin-remodelling complexes. Here, to generate mechanistic insights into the consequences of SMARCB1 mutation and to identify vulnerabilities, we contributed 14 SMARCB1-mutant cell lines to a near genome-wide CRISPR screen as part of the Cancer Dependency Map Project1-3. We report that the little-studied gene DDB1-CUL4-associated factor 5 (DCAF5) is required for the survival of SMARCB1-mutant cancers. We show that DCAF5 has a quality-control function for SWI/SNF complexes and promotes the degradation of incompletely assembled SWI/SNF complexes in the absence of SMARCB1. After depletion of DCAF5, SMARCB1-deficient SWI/SNF complexes reaccumulate, bind to target loci and restore SWI/SNF-mediated gene expression to levels that are sufficient to reverse the cancer state, including in vivo. Consequently, cancer results not from the loss of SMARCB1 function per se, but rather from DCAF5-mediated degradation of SWI/SNF complexes. These data indicate that therapeutic targeting of ubiquitin-mediated quality-control factors may effectively reverse the malignant state of some cancers driven by disruption of tumour suppressor complexes.


Subject(s)
Multiprotein Complexes , Mutation , Neoplasms , SMARCB1 Protein , Animals , Female , Humans , Male , Mice , Cell Line, Tumor , CRISPR-Cas Systems , Gene Editing , Neoplasms/genetics , Neoplasms/metabolism , SMARCB1 Protein/deficiency , SMARCB1 Protein/genetics , SMARCB1 Protein/metabolism , Tumor Suppressor Proteins/deficiency , Tumor Suppressor Proteins/genetics , Tumor Suppressor Proteins/metabolism , Multiprotein Complexes/chemistry , Multiprotein Complexes/metabolism , Proteolysis , Ubiquitin/metabolism
9.
Obesity (Silver Spring) ; 32(4): 723-732, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38321231

ABSTRACT

OBJECTIVE: The pathological expansion of white adipose tissue (WAT) in obesity involves adipocyte hypertrophy accompanied by expansion of the collagen-rich pericellular extracellular matrix (ECM) and development of crown-like structures (CLS). Traditionally, WAT morphology is assessed through immunohistochemical analysis of WAT sections. However, manual analysis of large histological sections is time-consuming, and the available digital tools for analyzing adipocyte size and pericellular ECM are limited. To address this gap, the authors developed the Adipose Tissue Analysis Toolkit (ATAT), an ImageJ plugin facilitating analysis of adipocyte size, WAT ECM, and CLS. METHODS AND RESULTS: ATAT utilizes local and image-level differentials in pixel intensity to independently threshold image background, distinguishing adipocyte-free tissue without user input. It accurately captures adipocytes in histological sections stained with common dyes and automates the analysis of adipocyte cross-sectional area, total-field, and localized region-of-interest ECM. ATAT allows fully automated batch analysis of histological images using default or user-defined adipocyte detection parameters. CONCLUSIONS: ATAT provides several advantages over existing WAT image analysis tools, enabling high-throughput analyses of adipocyte-specific parameters and facilitating the assessment of ECM changes associated with WAT remodeling due to weight changes and other pathophysiological alterations that affect WAT function.


Subject(s)
Adipocytes , Adipose Tissue , Humans , Adipocytes/pathology , Adipose Tissue, White , Obesity , Extracellular Matrix
10.
Am J Cardiol ; 217: 59-67, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38401652

ABSTRACT

Surgery for type A aortic dissection (TAAD) is associated with a high risk of early mortality. The prognostic impact of a new classification of the urgency of the procedure was evaluated in this multicenter cohort study. Data on consecutive patients who underwent surgery for acute TAAD were retrospectively collected in the multicenter, retrospective European Registry of TAAD (ERTAAD). The rates of in-hospital mortality of 3,902 consecutive patients increased along with the ERTAAD procedure urgency grades: urgent procedure 10.0%, emergency procedure grade 1 13.3%, emergency procedure grade 2 22.1%, salvage procedure grade 1 45.6%, and salvage procedure grade 2 57.1% (p <0.0001). Preoperative arterial lactate correlated with the urgency grades. Inclusion of the ERTAAD procedure urgency classification significantly improved the area under the receiver operating characteristics curves of the regression model and the integrated discrimination indexes and the net reclassification indexes. The risk of postoperative stroke/global brain ischemia, mesenteric ischemia, lower limb ischemia, dialysis, and acute heart failure increased along with the urgency grades. In conclusion, the urgency of surgical repair of acute TAAD, which seems to have a significant impact on the risk of in-hospital mortality, may be useful to improve the stratification of the operative risk of these critically ill patients. This study showed that salvage surgery for TAAD is justified because half of the patients may survive to discharge.


Subject(s)
Aortic Dissection , Azides , Deoxyglucose/analogs & derivatives , Humans , Retrospective Studies , Cohort Studies , Aortic Dissection/surgery , Prognosis , Treatment Outcome
11.
Nano Lett ; 23(23): 10779-10787, 2023 Dec 13.
Article in English | MEDLINE | ID: mdl-37987745

ABSTRACT

Electrochemical reduction of CO2 using Cu catalysts enables the synthesis of C2+ products including C2H4 and C2H5OH. In this study, Cu catalysts were fabricated using plasma-enhanced atomic layer deposition (PEALD), achieving conformal deposition of catalysts throughout 3-D gas diffusion electrode (GDE) substrates while maintaining tunable control of Cu nanoparticle size and areal loading. The electrochemical CO2 reduction at the Cu surface yielded a total Faradaic efficiency (FE) > 75% for C2+ products. Parasitic hydrogen evolution was minimized to a FE of ∼10%, and a selectivity of 42.2% FE for C2H4 was demonstrated. Compared to a line-of-sight physical vapor deposition method, PEALD Cu catalysts show significant suppression of C1 products compared to C2+, which is associated with improved control of catalyst morphology and conformality within the porous GDE substrate. Finally, PEALD Cu catalysts demonstrated a stable performance for 15 h with minimal reduction in the C2H4 production rate.

12.
Am J Cardiol ; 209: 24-28, 2023 12 15.
Article in English | MEDLINE | ID: mdl-37848171

ABSTRACT

Transcatheter aortic valve implantation (TAVI) has brought in recent years relief of cardiac-induced symptoms to a large number of patients with aortic stenosis. Whether it is better to use TAVI for the treatment of aortic valve stenosis superimposed on a congenitally bicuspid valve has been debated in contrast to its proved usefulness in aortic valve stenosis involving a tricuspid aortic valve. From January 2020 to March 2023, surgical aortic valve replacement of TAVI valve and native aortic valve was done in 6 patients. The clinical findings of the patients and morphologic findings from the surgical specimens submitted to the cardiac pathology department were subsequently examined. All the 6 native aortic valves had bicuspid configuration. The TAVI valve in each patient was excised from 9 to 88 months (mean 36 months) after it had been implanted because of paravalvular leak in 4, severe stenosis of the prosthetic valve in 1, and bioprosthetic cuspal degeneration in 1. Prosthetic valve endocarditis was clinically suspected in 2 patients, but the specimen culture was negative. Before surgical aortic valve replacement, 3 patients experienced stroke after TAVI. All 6 patients had low hemoglobin levels (mean 9.5 mg/100 ml) and low hematocrit levels (mean 29.5%). Reticulocyte count was available in 4 patients and was increased in all (mean 3.5%). When the stenotic native aortic valve configuration is bicuspid, the raphe tends to be calcified first and located perpendicular to the flow of the blood and may prevent the ring of the caged bioprosthesis from being transferred to the aortic wall, which is a requirement for full opening of the lumen of the bioprosthesis. Thus, thorough consideration needs to be made before performing TAVI in patients whose native aortic valve is stenotic and bicuspid.


Subject(s)
Aortic Valve Stenosis , Bioprosthesis , Endocarditis, Bacterial , Heart Valve Prosthesis , Transcatheter Aortic Valve Replacement , Humans , Aortic Valve/surgery , Constriction, Pathologic/surgery , Aortic Valve Stenosis/surgery , Transcatheter Aortic Valve Replacement/adverse effects , Treatment Outcome
13.
Cell Rep Methods ; 3(10): 100599, 2023 Oct 23.
Article in English | MEDLINE | ID: mdl-37797618

ABSTRACT

For large libraries of small molecules, exhaustive combinatorial chemical screens become infeasible to perform when considering a range of disease models, assay conditions, and dose ranges. Deep learning models have achieved state-of-the-art results in silico for the prediction of synergy scores. However, databases of drug combinations are biased toward synergistic agents and results do not generalize out of distribution. During 5 rounds of experimentation, we employ sequential model optimization with a deep learning model to select drug combinations increasingly enriched for synergism and active against a cancer cell line-evaluating only ∼5% of the total search space. Moreover, we find that learned drug embeddings (using structural information) begin to reflect biological mechanisms. In silico benchmarking suggests search queries are ∼5-10× enriched for highly synergistic drug combinations by using sequential rounds of evaluation when compared with random selection or ∼3× when using a pretrained model.


Subject(s)
Computational Biology , Neoplasms , Humans , Drug Synergism , Computational Biology/methods , Drug Combinations , Neoplasms/drug therapy
14.
Proc (Bayl Univ Med Cent) ; 36(6): 772-774, 2023.
Article in English | MEDLINE | ID: mdl-37829236

ABSTRACT

William Harvey (1578-1658) discovered that blood flows in a circle and described this new finding in a short book in 1628. He had superb educational opportunities but also faced great difficulties, which he met with personal and professional resilience. A study of his life is worthwhile. Presented here are 11 lessons drawn from Harvey's life and legacy.

15.
Am J Reprod Immunol ; 90(4): e13773, 2023 10.
Article in English | MEDLINE | ID: mdl-37766405

ABSTRACT

PROBLEM: Anovulatory infertility is commonly associated with hyperandrogenemia (elevated testosterone, T), insulin resistance, obesity, and white adipose tissue (WAT) dysfunction associated with adipocyte hypertrophy. However, whether hyperandrogenemia and adipocyte hypertrophy per se induce a proinflammatory response is unknown. METHOD OF STUDY: Young adult female rhesus macaques were exposed to an obesogenic Western-style diet (WSD) in the presence of elevated circulating testosterone (T+WSD) or a low-fat control diet with no exogenous T. Immune cells residing in visceral omental white adipose tissue (OM-WAT), corpus luteum and the contralateral ovary, endometrium, lymph nodes, bone marrow, and peripheral blood mononuclear cells were characterized by flow cytometry during the luteal phase of the reproductive cycle. RESULTS: Following one year of treatment, T+WSD animals became more insulin-resistant and exhibited increased body fat and adipocyte hypertrophy compared to controls. T+WSD treatment did not induce macrophage polarization toward a proinflammatory phenotype in the tissues examined. Additionally, T+WSD treatment did not affect TNFα production by bone marrow macrophages in response to toll-like receptor agonists. While the major lymphoid subsets were not significantly affected by T+WSD treatment, we observed a significant reduction in the frequency of effector memory CD8+ T-cells (Tem) in OM-WAT, but not in other tissues. Notably, OM-WAT Tem frequencies were negatively correlated with insulin resistance as assessed by the Homeostatic Model Assessment for Insulin Resistance (HOMA-IR). CONCLUSION: This study shows that short-term T+WSD treatment induces weight gain, insulin resistance, and adipocyte hypertrophy, but does not have a significant effect on systemic and tissue-resident proinflammatory markers, suggesting that adipocyte hypertrophy and mild hyperandrogenemia alone are not sufficient to induce a proinflammatory response.


Subject(s)
Hyperandrogenism , Insulin Resistance , Polycystic Ovary Syndrome , Humans , Animals , Female , Macaca mulatta , Insulin Resistance/physiology , Testosterone/pharmacology , Leukocytes, Mononuclear , Hyperandrogenism/complications , Adipocytes/pathology , Hypertrophy/complications , Diet
16.
J Clin Oncol ; 41(24): 4045-4053, 2023 08 20.
Article in English | MEDLINE | ID: mdl-37267580

ABSTRACT

Data-driven basic, translational, and clinical research has resulted in improved outcomes for children, adolescents, and young adults (AYAs) with pediatric cancers. However, challenges in sharing data between institutions, particularly in research, prevent addressing substantial unmet needs in children and AYA patients diagnosed with certain pediatric cancers. Systematically collecting and sharing data from every child and AYA can enable greater understanding of pediatric cancers, improve survivorship, and accelerate development of new and more effective therapies. To accomplish this goal, the Childhood Cancer Data Initiative (CCDI) was launched in 2019 at the National Cancer Institute. CCDI is a collaborative community endeavor supported by a 10-year, $50-million (in US dollars) annual federal investment. CCDI aims to learn from every patient diagnosed with a pediatric cancer by designing and building a data ecosystem that facilitates data collection, sharing, and analysis for researchers, clinicians, and patients across the cancer community. For example, CCDI's Molecular Characterization Initiative provides comprehensive clinical molecular characterization for children and AYAs with newly diagnosed cancers. Through these efforts, the CCDI strives to provide clinical benefit to patients and improvements in diagnosis and care through data-focused research support and to build expandable, sustainable data resources and workflows to advance research well past the planned 10 years of the initiative. Importantly, if CCDI demonstrates the success of this model for pediatric cancers, similar approaches can be applied to adults, transforming both clinical research and treatment to improve outcomes for all patients with cancer.


Subject(s)
Neoplasms , Adolescent , United States/epidemiology , Humans , Child , Young Adult , Neoplasms/therapy , Ecosystem , Data Collection , National Cancer Institute (U.S.)
17.
Nature ; 618(7963): 180-187, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37225980

ABSTRACT

For cells to initiate and sustain a differentiated state, it is necessary that a 'memory' of this state is transmitted through mitosis to the daughter cells1-3. Mammalian switch/sucrose non-fermentable (SWI/SNF) complexes (also known as Brg1/Brg-associated factors, or BAF) control cell identity by modulating chromatin architecture to regulate gene expression4-7, but whether they participate in cell fate memory is unclear. Here we provide evidence that subunits of SWI/SNF act as mitotic bookmarks to safeguard cell identity during cell division. The SWI/SNF core subunits SMARCE1 and SMARCB1 are displaced from enhancers but are bound to promoters during mitosis, and we show that this binding is required for appropriate reactivation of bound genes after mitotic exit. Ablation of SMARCE1 during a single mitosis in mouse embryonic stem cells is sufficient to disrupt gene expression, impair the occupancy of several established bookmarks at a subset of their targets and cause aberrant neural differentiation. Thus, SWI/SNF subunit SMARCE1 has a mitotic bookmarking role and is essential for heritable epigenetic fidelity during transcriptional reprogramming.


Subject(s)
Cell Differentiation , Chromosomal Proteins, Non-Histone , Epigenesis, Genetic , Mitosis , Animals , Mice , Cell Differentiation/genetics , Chromatin/genetics , Chromatin Assembly and Disassembly/genetics , Nuclear Proteins/metabolism , Transcription Factors/metabolism , Mitosis/genetics , Chromosomal Proteins, Non-Histone/deficiency , Chromosomal Proteins, Non-Histone/genetics , Chromosomal Proteins, Non-Histone/metabolism , Protein Subunits/metabolism , Mouse Embryonic Stem Cells/metabolism , Enhancer Elements, Genetic/genetics , Promoter Regions, Genetic/genetics , Cell Division/genetics , Epigenesis, Genetic/genetics
18.
Am J Cardiol ; 195 Suppl 1: S2-S30, 2023 05 15.
Article in English | MEDLINE | ID: mdl-37059608
19.
Sci Rep ; 13(1): 841, 2023 01 16.
Article in English | MEDLINE | ID: mdl-36646824

ABSTRACT

Maternal malnutrition increases fetal and neonatal morbidity, partly by affecting placental function and morphology, but its impact on placental hemodynamics are unknown. Our objective was to define the impact of maternal malnutrition on placental oxygen reserve and perfusion in vivo in a rhesus macaque model of protein restriction (PR) using advanced imaging. Animals were fed control (CON, 26% protein), 33% PR diet (17% protein), or a 50% PR diet (13% protein, n = 8/group) preconception and throughout pregnancy. Animals underwent Doppler ultrasound and fetal biometry followed by MRI at gestational days 85 (G85) and 135 (G135; term is G168). Pregnancy loss rates were 0/8 in CON, 1/8 in 33% PR, and 3/8 in 50% PR animals. Fetuses of animals fed a 50% PR diet had a smaller abdominal circumference (G135, p < 0.01). On MRI, placental blood flow was decreased at G135 (p < 0.05) and placental oxygen reserve was reduced (G85, p = 0.05; G135, p = 0.01) in animals fed a 50% PR diet vs. CON. These data demonstrate that a 50% PR diet reduces maternal placental perfusion, decreases fetal oxygen availability, and increases fetal mortality. These alterations in placental hemodynamics may partly explain human growth restriction and stillbirth seen with severe PR diets in the developing world.


Subject(s)
Diet, Protein-Restricted , Malnutrition , Animals , Female , Pregnancy , Diet, Protein-Restricted/adverse effects , Fetal Growth Retardation/metabolism , Hemodynamics , Macaca mulatta/metabolism , Maternal-Fetal Exchange , Oxygen/metabolism , Placenta/metabolism
20.
Am J Cardiol ; 189: 137-147, 2023 02 15.
Article in English | MEDLINE | ID: mdl-36642461

ABSTRACT

Described herein are findings in 55 non-infected bioprostheses that had been in the aortic valve position from 2 to 276 months (mean 107). The major purpose of this study was to illustrate the variable causes prompting excision of the bioprostheses. Fifty-three (96%) patients survived ≥ 30 days following the bioprosthetic excision and 50 (91%) patients lived ≥1 year postoperatively. The techniques used to explant the bioprostheses appear to vary considerably among the operating surgeons.


Subject(s)
Bioprosthesis , Heart Valve Prosthesis , Humans , Aortic Valve/surgery , Reoperation , Prosthesis Failure
SELECTION OF CITATIONS
SEARCH DETAIL
...