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1.
Energy Fuels ; 38(13): 11947-11965, 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38984060

ABSTRACT

The use of adsorbents for direct air capture (DAC) of CO2 is regarded as a promising and essential carbon dioxide removal technology to help meet the goals outlined by the 2015 Paris Agreement. A class of adsorbents that has gained significant attention for this application is ultramicroporous metal organic frameworks (MOFs). However, the necessary data needed to facilitate process scale evaluation of these materials is not currently available. Here, we investigate TIFSIX-3-Ni, a previously reported ultramicroporous MOF for DAC, and measure several physicochemical and equilibrium adsorption properties. We report its crystal structure, textural properties, thermal stability, specific heat capacity, CO2, N2, and H2O equilibrium adsorption isotherms at multiple temperatures, and Ar and O2 isotherms at a single temperature. For CO2, N2, and H2O, we also report isotherm model fitting parameters and calculate heats of adsorption. We assess the manufacturability and process stability of TIFSIX-3-Ni by investigating the impact of batch reproducibility, binderless pelletization, humidity, and adsorption-desorption cycling (50 cycles) on its crystal structure, textural properties, and CO2 adsorption. For pelletized TIFSIX-3-Ni, we also report its skeletal, pellet, and bed density, total pore volume, and pellet porosity. Overall, our data enable initial process modeling and optimization studies to evaluate TIFSIX-3-Ni for DAC at the process scale. They also highlight the possibility to pelletize TIFSIX-3-Ni and the limited stability of the MOF under humid and oxidative conditions as well as upon multiple adsorption-desorption cycles.

2.
J Chem Eng Data ; 68(12): 3499-3511, 2023 Dec 14.
Article in English | MEDLINE | ID: mdl-38115913

ABSTRACT

Direct air capture (DAC) using solid adsorbents has gained significant attention as a carbon dioxide removal (CDR) technology to help limit global temperature rise to below 2 °C. One large area of focus is the development of new adsorbent materials for DAC. However, the necessary data needed to employ these materials in process models for adsorbent screening are rarely available. Here, we showcase Purolite A110, a commercially available amine-functionalized polymeric resin, as a new candidate adsorbent for DAC and compare its properties to a current benchmark, Lewatit VP OC 1065. For both materials, we report their chemical features and composition, skeletal, particle, and bed density, total pore volume, particle porosity, BET area, thermal stability, and specific heat capacity. We determine their equilibrium sorption properties by measuring the volumetric CO2 isotherms at 288, 298, 308, 333, 343, 353, and 393 K, N2 and H2O isotherms at 288, 298, and 308 K, and Ar and O2 isotherms at 298 K. For CO2, N2, and H2O, we also present the corresponding isotherm model fitting parameters and heats of adsorption. These data can help facilitate process modeling and optimization studies to properly assess these adsorbents at scale.

3.
NPJ Regen Med ; 8(1): 63, 2023 Nov 07.
Article in English | MEDLINE | ID: mdl-37935709

ABSTRACT

The liver has a remarkable regenerative capacity. Nevertheless, under chronic liver-damaging conditions, this capacity becomes exhausted, allowing the accumulation of fibrotic tissue and leading to end-stage liver disease. Enhancing the endogenous regenerative capacity by targeting regeneration breaks is an innovative therapeutic approach. We set up an in vivo functional genetic screen to identify such regeneration breaks. As the top hit, we identified Microfibril associated protein 4 (Mfap4). Knockdown of Mfap4 in hepatocytes enhances cell proliferation, accelerates liver regeneration, and attenuates chronic liver disease by reducing liver fibrosis. Targeting Mfap4 modulates several liver regeneration-related pathways including mTOR. Our research opens the way to siRNA-based therapeutics to enhance hepatocyte-based liver regeneration.

4.
J Immunother Cancer ; 11(8)2023 08.
Article in English | MEDLINE | ID: mdl-37586766

ABSTRACT

BACKGROUND: Combination therapy with radioembolization (yttrium-90)-resin microspheres) followed by nivolumab has shown a promising response rate of 30.6% in a Phase II trial (CA209-678) for advanced hepatocellular carcinoma (HCC); however, the response mechanisms and relevant biomarkers remain unknown. METHODS: By collecting both pretreatment and on-treatment samples, we performed multimodal profiling of tissue and blood samples and investigated molecular changes associated with favorable responses in 33 patients from the trial. RESULTS: We found that higher tumor mutation burden, NCOR1 mutations and higher expression of interferon gamma pathways occurred more frequently in responders. Meanwhile, non-responders tended to be enriched for a novel Asian-specific transcriptomic subtype (Kaya_P2) with a high frequency of chromosome 16 deletions and upregulated cell cycle pathways. Strikingly, unlike other cancer types, we did not observe any association between T-cell populations and treatment response, but tumors from responders had a higher proportion of CXCL9+/CXCR3+ macrophages. Moreover, biomarkers discovered in previous immunotherapy trials were not predictive in the current cohort, suggesting a distinctive molecular landscape associated with differential responses to the combination therapy. CONCLUSIONS: This study unraveled extensive molecular changes underlying distinctive responses to the novel treatment and pinpointed new directions for harnessing combination therapy in patients with advanced HCC.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Humans , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/genetics , Microspheres , Nivolumab/pharmacology , Nivolumab/therapeutic use , Liver Neoplasms/drug therapy , Liver Neoplasms/genetics , Chromosome Deletion
5.
Lancet Reg Health West Pac ; 39: 100830, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37484709

ABSTRACT

Background: Pacific Island Countries (PICs) face unique challenges in providing surgical care. We assessed the surgical care capacity of five PICs to inform the development of National Surgical, Obstetric and Anaesthesia Plans (NSOAP). Methods: We conducted a cross-sectional survey of 26 facilities in Fiji, Tonga, Vanuatu, Cook Islands, and Palau using the World Health Organization - Program in Global Surgery and Social Change Surgical Assessment Tool. Findings: Eight referral and 18 first-level hospitals containing 39 functioning operating theatres, 41 post-anaesthesia care beds, and 44 intensive care unit beds served a population of 1,321,000 across the five countries. Most facilities had uninterrupted access to electricity, water, internet, and oxygen. However, CT was only available in 2/8 referral hospitals, MRI in 1/8, and timely blood transfusions in 4/8. The surgical, obstetric, and anaesthetist specialist density per 100,000 people was the highest in Palau (49.7), followed by Cook Islands (22.9), Tonga (9.9), Fiji (7.1), and Vanuatu (5.0). There were four radiologists and 3.5 pathologists across the five countries. Surgical volume per 100,000 people was the lowest in Vanuatu (860), followed by Fiji (2,247), Tonga (2,864), Cook Islands (6,747), and Palau (8,606). The in-hospital peri-operative mortality rate (POMR) was prospectively monitored in Tonga and Cook Islands but retrospectively measured in other countries. POMR was below 1% in all five countries. Interpretation: Whilst PICs share common challenges in providing specialised tertiary services, there is substantial diversity between the countries. Strategies to strengthen surgical systems should incorporate both local contextualisation within each PIC and regional collaboration between PICs. Funding: None.

6.
J Prim Health Care ; 15(2): 176-183, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37390040

ABSTRACT

Introduction The global burden of diabetes mellitus (diabetes) is significant and of increasing concern with more pregnant women being diagnosed with gestational diabetes mellitus (GDM). The Cook Islands face mounting pressures to address diabetes alongside competing population health needs and priorities. Cook Islands residents frequently travel to New Zealand to access health services. Inadequate information systems also make it difficult for countries to prioritise preventative measures for investment. In the absence of good data to inform effective diabetes preventative and treatment measures, people with diabetes are likely to progress to complications which will burden society and health systems in the Cook Islands and New Zealand. Aim To determine the prevalence of diabetes and prediabetes, and incidence of GDM, in the Cook Islands. Methods We analysed two Te Marae Ora Cook Islands Ministry of Health datasets, the Non-Communicable Diseases (NCD) register examining demographic data for the period 1967 to December 2018 and same for the GDM register from January 2009 to December 2018. Results Of the 1270 diabetes cases, 53% were female and half were aged 45-64 years. There were 54 pre-diabetes cases and 146 GDM. Of the 20 GDM cases who developed type 2 diabetes, 80% were diagnosed before the age of 40 years. Data quality was poor. Discussion The Cook Islands diabetes registers provide important data to inform priorities for diabetes-related preventative and treatment measures. A data analyst has been employed to ensure quality, regularly audited data and information systems.


Subject(s)
Diabetes Mellitus, Type 2 , Prediabetic State , Pregnancy , Female , Humans , Male , Diabetes Mellitus, Type 2/epidemiology , Clinical Audit , New Zealand/epidemiology , Polynesia/epidemiology
7.
Nat Commun ; 14(1): 1726, 2023 03 28.
Article in English | MEDLINE | ID: mdl-36977662

ABSTRACT

Mis-sense mutations affecting TP53 promote carcinogenesis both by inactivating tumor suppression, and by conferring pro-carcinogenic activities. We report here that p53 DNA-binding domain (DBD) and transactivation domain (TAD) mis-sense mutants unexpectedly activate pro-carcinogenic epidermal growth factor receptor (EGFR) signaling via distinct, previously unrecognized molecular mechanisms. DBD- and TAD-specific TP53 mutants exhibited different cellular localization and induced distinct gene expression profiles. In multiple tissues, EGFR is stabilized by TAD and DBD mutants in the cytosolic and nuclear compartments respectively. TAD mutants promote EGFR-mediated signaling by enhancing EGFR interaction with AKT via DDX31 in the cytosol. Conversely, DBD mutants maintain EGFR activity in the nucleus, by blocking EGFR interaction with the phosphatase SHP1, triggering c-Myc and Cyclin D1 upregulation. Our findings suggest that p53 mutants carrying gain-of-function, mis-sense mutations affecting two different domains form new protein complexes that promote carcinogenesis by enhancing EGFR signaling via distinctive mechanisms, exposing clinically relevant therapeutic vulnerabilities.


Subject(s)
ErbB Receptors , Tumor Suppressor Protein p53 , Tumor Suppressor Protein p53/metabolism , ErbB Receptors/genetics , ErbB Receptors/metabolism , Signal Transduction , Transcriptional Activation , Phosphorylation
8.
PLoS Negl Trop Dis ; 16(11): e0010626, 2022 11.
Article in English | MEDLINE | ID: mdl-36441828

ABSTRACT

BACKGROUND: Arthropod-borne diseases pose a significant and increasing risk to global health. Given its rapid dissemination, causing large-scale outbreaks with severe human infections and economic loss, the Chikungunya virus (CHIKV) is one of the most important arboviruses worldwide. Despite its significance, the real global impact of CHIKV remains underestimated as outbreak data are often incomplete and based solely on syndromic surveillance. During 2011-2016, the South Pacific Region was severely affected by several CHIKV-epidemics, yet the area is still underrepresented in arboviral research. METHODS: 465 outpatient serum samples collected between 08/2016 and 04/2017 on three islands of the island states Vanuatu (Espiritu Santo) and the Cook Islands (Rarotonga, Aitutaki) were tested for anti-CHIKV specific antibodies using Enzyme-linked immunosorbent Assays. RESULTS: A total of 30% (Cook Islands) and 8% (Vanuatu) of specimens were found positive for anti-CHIKV specific antibodies with major variations in national and intranational immunity levels. Seroprevalence throughout all age groups was relatively constant. Four potential outbreak-protective factors were identified by comparing the different study settings: presence of Ae. albopictus (in absence of ECSA E1-A226V-mutation CHIKV), as well as low levels of human population densities, residents' travel activity and tourism. CONCLUSION: This is the first seroprevalence study focussing on an arboviral disease in the Cook Islands and Vanuatu. It highlights the impact of the 2014/2015 CHIKV epidemic on the Cook Islands population and shows that a notable part of the Vanuatu test population was exposed to CHIKV although no outbreaks were reported. Our findings supplement the knowledge concerning CHIKV epidemics in the South Pacific Region and contribute to a better understanding of virus dissemination, including outbreak modifying factors. This study may support preventive and rapid response measures in affected areas, travel-related risk assessment and infection identification in returning travellers. TRIAL REGISTRATION: ClinicalTrials.gov Aachen: 051/16_09/05/2016 Cook Islands Ref.: #16-16 Vanuatu Ref.: MOH/DG 10/1/1-GKT/lr.


Subject(s)
Chikungunya virus , Humans , Seroepidemiologic Studies , Chikungunya virus/genetics , Social Factors , Travel , Polynesia/epidemiology
9.
Mol Psychiatry ; 27(11): 4510-4525, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36056172

ABSTRACT

Depression and anxiety are major global health burdens. Although SSRIs targeting the serotonergic system are prescribed over 200 million times annually, they have variable therapeutic efficacy and side effects, and mechanisms of action remain incompletely understood. Here, we comprehensively characterise the molecular landscape of gene regulatory changes associated with fluoxetine, a widely-used SSRI. We performed multimodal analysis of SSRI response in 27 mammalian brain regions using 310 bulk RNA-seq and H3K27ac ChIP-seq datasets, followed by in-depth characterisation of two hippocampal regions using single-cell RNA-seq (20 datasets). Remarkably, fluoxetine induced profound region-specific shifts in gene expression and chromatin state, including in the nucleus accumbens shell, locus coeruleus and septal areas, as well as in more well-studied regions such as the raphe and hippocampal dentate gyrus. Expression changes were strongly enriched at GWAS loci for depression and antidepressant drug response, stressing the relevance to human phenotypes. We observed differential expression at dozens of signalling receptors and pathways, many of which are previously unknown. Single-cell analysis revealed stark differences in fluoxetine response between the dorsal and ventral hippocampal dentate gyri, particularly in oligodendrocytes, mossy cells and inhibitory neurons. Across diverse brain regions, integrative omics analysis consistently suggested increased energy metabolism via oxidative phosphorylation and mitochondrial changes, which we corroborated in vitro; this may thus constitute a shared mechanism of action of fluoxetine. Similarly, we observed pervasive chromatin remodelling signatures across the brain. Our study reveals unexpected regional and cell type-specific heterogeneity in SSRI action, highlights under-studied brain regions that may play a major role in antidepressant response, and provides a rich resource of candidate cell types, genes, gene regulatory elements and pathways for mechanistic analysis and identifying new therapeutic targets for depression and anxiety.


Subject(s)
Chromatin Assembly and Disassembly , Fluoxetine , Humans , Antidepressive Agents/pharmacology , Brain/metabolism , Energy Metabolism/genetics , Fluoxetine/pharmacology , Fluoxetine/metabolism , Mammals , Multiomics , Animals
10.
Front Cell Dev Biol ; 10: 938625, 2022.
Article in English | MEDLINE | ID: mdl-35846378

ABSTRACT

Cancer is characterized as a reversion of a differentiated cell to a primitive cell state that recapitulates, in many aspects, features of embryonic cells. This review explores the current knowledge of developmental mechanisms that are essential for embryonic mouse mammary gland development, with a particular focus on genes and signaling pathway components that are essential for the induction, morphogenesis, and lineage specification of the mammary gland. The roles of these same genes and signaling pathways in mammary gland or breast tumorigenesis and metastasis are then summarized. Strikingly, key embryonic developmental pathways are often reactivated or dysregulated during tumorigenesis and metastasis in processes such as aberrant proliferation, epithelial-to-mesenchymal transition (EMT), and stem cell potency which affects cellular lineage hierarchy. These observations are in line with findings from recent studies using lineage tracing as well as bulk- and single-cell transcriptomics that have uncovered features of embryonic cells in cancer and metastasis through the identification of cell types, cell states and characterisation of their dynamic changes. Given the many overlapping features and similarities of the molecular signatures of normal development and cancer, embryonic molecular signatures could be useful prognostic markers for cancer. In this way, the study of embryonic development will continue to complement the understanding of the mechanisms of cancer and aid in the discovery of novel therapeutic targets and strategies.

12.
Stem Cells ; 40(1): 112-122, 2022 03 03.
Article in English | MEDLINE | ID: mdl-35511868

ABSTRACT

Mammary gland homeostasis is maintained by adult tissue stem-progenitor cells residing within the luminal and basal epithelia. Dysregulation of mammary stem cells is a key mechanism for cancer development. However, stem cell characterization is challenging because reporter models using cell-specific promoters do not fully recapitulate the mammary stem cell populations. We previously found that a 270-basepair Runx1 enhancer element, named eR1, marked stem cells in the blood and stomach. Here, we identified eR1 activity in a rare subpopulation of the ERα-negative luminal epithelium in mouse mammary glands. Lineage-tracing using an eR1-CreERT2 mouse model revealed that eR1+ luminal cells generated the entire luminal lineage and milk-secreting alveoli-eR1 therefore specifically marks lineage-restricted luminal stem cells. eR1-targeted-conditional knockout of Runx1 led to the expansion of luminal epithelial cells, accompanied by elevated ERα expression. Our findings demonstrate a definitive role for Runx1 in the regulation of the eR1-positive luminal stem cell proliferation during mammary homeostasis. Our findings identify a mechanistic link for Runx1 in stem cell proliferation and its dysregulation in breast cancer. Runx1 inactivation is therefore likely to be an early hit in the cell-of-origin of ERα+ luminal type breast cancer.


Subject(s)
Estrogen Receptor alpha , Mammary Glands, Animal , Animals , Cell Lineage , Core Binding Factor Alpha 2 Subunit/genetics , Core Binding Factor Alpha 2 Subunit/metabolism , Enhancer Elements, Genetic/genetics , Epithelial Cells/metabolism , Estrogen Receptor alpha/genetics , Estrogen Receptor alpha/metabolism , Mice , Stem Cells/metabolism
13.
Oncogene ; 41(13): 1986-2002, 2022 03.
Article in English | MEDLINE | ID: mdl-35236967

ABSTRACT

Inhibitors of the mitotic kinase PLK1 yield objective responses in a subset of refractory cancers. However, PLK1 overexpression in cancer does not correlate with drug sensitivity, and the clinical development of PLK1 inhibitors has been hampered by the lack of patient selection marker. Using a high-throughput chemical screen, we discovered that cells deficient for the tumor suppressor ARID1A are highly sensitive to PLK1 inhibition. Interestingly this sensitivity was unrelated to canonical functions of PLK1 in mediating G2/M cell cycle transition. Instead, a whole-genome CRISPR screen revealed PLK1 inhibitor sensitivity in ARID1A deficient cells to be dependent on the mitochondrial translation machinery. We find that ARID1A knock-out (KO) cells have an unusual mitochondrial phenotype with aberrant biogenesis, increased oxygen consumption/expression of oxidative phosphorylation genes, but without increased ATP production. Using expansion microscopy and biochemical fractionation, we see that a subset of PLK1 localizes to the mitochondria in interphase cells. Inhibition of PLK1 in ARID1A KO cells further uncouples oxygen consumption from ATP production, with subsequent membrane depolarization and apoptosis. Knockdown of specific subunits of the mitochondrial ribosome reverses PLK1-inhibitor induced apoptosis in ARID1A deficient cells, confirming specificity of the phenotype. Together, these findings highlight a novel interphase role for PLK1 in maintaining mitochondrial fitness under metabolic stress, and a strategy for therapeutic use of PLK1 inhibitors. To translate these findings, we describe a quantitative microscopy assay for assessment of ARID1A protein loss, which could offer a novel patient selection strategy for the clinical development of PLK1 inhibitors in cancer.


Subject(s)
Cell Cycle Proteins , DNA-Binding Proteins , Neoplasms , Protein Serine-Threonine Kinases , Proto-Oncogene Proteins , Transcription Factors , Adenosine Triphosphate/metabolism , Apoptosis , Cell Cycle Proteins/genetics , Cell Line, Tumor , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Humans , Neoplasms/drug therapy , Neoplasms/genetics , Oxygen Consumption , Protein Kinase Inhibitors/pharmacology , Protein Serine-Threonine Kinases/genetics , Proto-Oncogene Proteins/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism , Polo-Like Kinase 1
14.
Proc Natl Acad Sci U S A ; 119(10): e2113233119, 2022 03 08.
Article in English | MEDLINE | ID: mdl-35235448

ABSTRACT

SignificanceOur work focuses on the critical longstanding question of the nontranscriptional role of p53 in tumor suppression. We demonstrate here that poly(ADP-ribose) polymerase (PARP)-dependent modification of p53 enables rapid recruitment of p53 to damage sites, where it in turn directs early repair pathway selection. Specifically, p53-mediated recruitment of 53BP1 at early time points promotes nonhomologous end joining over the more error-prone microhomology end-joining. Similarly, p53 directs nucleotide excision repair by mediating DDB1 recruitment. This property of p53 also correlates with tumor suppression in vivo. Our study provides mechanistic insight into how certain transcriptionally deficient p53 mutants may retain tumor-suppressive functions through regulating the DNA damage response.


Subject(s)
DNA Damage , DNA End-Joining Repair , Tumor Suppressor Protein p53/metabolism , Tumor Suppressor p53-Binding Protein 1/metabolism , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism , Cell Line, Tumor , DNA-Binding Proteins , Humans , Mutation , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , Protein Domains , Tumor Suppressor Protein p53/genetics , Tumor Suppressor p53-Binding Protein 1/genetics
15.
Sci Adv ; 7(41): eabh2443, 2021 Oct 08.
Article in English | MEDLINE | ID: mdl-34613780

ABSTRACT

Cell state transitions control the functional behavior of cancer cells. Epithelial-to-mesenchymal transition (EMT) confers cancer stem cell-like properties, enhanced tumorigenicity and drug resistance to tumor cells, while mesenchymal-epithelial transition (MET) reverses these phenotypes. Using high-throughput chemical library screens, retinoids are found to be potent promoters of MET that inhibit tumorigenicity in basal-like breast cancer. Cell state transitions are defined by reprogramming of lipid metabolism. Retinoids bind cognate nuclear receptors, which target lipid metabolism genes, thereby redirecting fatty acids for ß-oxidation in the mesenchymal cell state towards lipid storage in the epithelial cell state. Disruptions of key metabolic enzymes mediating this flux inhibit MET. Conversely, perturbations to fatty acid oxidation (FAO) rechannel fatty acid flux and promote a more epithelial cell phenotype, blocking EMT-driven breast cancer metastasis in animal models. FAO impinges on the epigenetic control of EMT through acetyl-CoA-dependent regulation of histone acetylation on EMT genes, thus determining cell states.

16.
Circ Res ; 127(6): 761-777, 2020 08 28.
Article in English | MEDLINE | ID: mdl-32529949

ABSTRACT

RATIONALE: Identifying genetic markers for heterogeneous complex diseases such as heart failure is challenging and requires prohibitively large cohort sizes in genome-wide association studies to meet the stringent threshold of genome-wide statistical significance. On the other hand, chromatin quantitative trait loci, elucidated by direct epigenetic profiling of specific human tissues, may contribute toward prioritizing subthreshold variants for disease association. OBJECTIVE: Here, we captured noncoding genetic variants by performing epigenetic profiling for enhancer H3K27ac chromatin immunoprecipitation followed by sequencing in 70 human control and end-stage failing hearts. METHODS AND RESULTS: We have mapped a comprehensive catalog of 47 321 putative human heart enhancers and promoters. Three thousand eight hundred ninety-seven differential acetylation peaks (FDR [false discovery rate], 5%) pointed to pathways altered in heart failure. To identify cardiac histone acetylation quantitative trait loci (haQTLs), we regressed out confounding factors including heart failure disease status and used the G-SCI (Genotype-independent Signal Correlation and Imbalance) test1 to call out 1680 haQTLs (FDR, 10%). RNA sequencing performed on the same heart samples proved a subset of haQTLs to have significant association also to gene expression (expression quantitative trait loci), either in cis (180) or through long-range interactions (81), identified by Hi-C (high-throughput chromatin conformation assay) and HiChIP (high-throughput protein centric chromatin) performed on a subset of hearts. Furthermore, a concordant relationship between the gain or disruption of TF (transcription factor)-binding motifs, inferred from alternative alleles at the haQTLs, implied a surprising direct association between these specific TF and local histone acetylation in human hearts. Finally, 62 unique loci were identified by colocalization of haQTLs with the subthreshold loci of heart-related genome-wide association studies datasets. CONCLUSIONS: Disease and phenotype association for 62 unique loci are now implicated. These loci may indeed mediate their effect through modification of enhancer H3K27 acetylation enrichment and their corresponding gene expression differences (bioRxiv: https://doi.org/10.1101/536763). Graphical Abstract: A graphical abstract is available for this article.


Subject(s)
Epigenome , Genetic Variation , Heart Failure/genetics , Histones/genetics , Acetylation , Adult , Aged , Aged, 80 and over , Case-Control Studies , Chromatin Immunoprecipitation , Databases, Genetic , Epigenesis, Genetic , Epigenomics , Female , Genetic Predisposition to Disease , Heart Failure/diagnosis , Heart Failure/physiopathology , High-Throughput Nucleotide Sequencing , Histones/metabolism , Humans , Male , Middle Aged , Phenotype , Quantitative Trait Loci
17.
Cureus ; 12(3): e7390, 2020 Mar 24.
Article in English | MEDLINE | ID: mdl-32337117

ABSTRACT

Background Most family caregivers of stroke patients in Malaysia do not receive adequate prior preparation or training. This study aimed to determine levels of patient positioning knowledge and caregiving self-efficacy among caregivers of stroke patients. Methods This cross-sectional study was conducted at an urban teaching hospital involving 128 caregivers of stroke patients. The caregivers were conveniently sampled and completed the data collection forms, which comprised their socio-demographic data, patients' functional status, the Caregiving Knowledge For Stroke Questionnaire: Patient Positioning (CKQ-My© Patient Positioning) to measure caregiver's knowledge on patient positioning, and the Family Caregiver Activation Tool (FCAT©) to measure caregivers' self-efficacy in managing the patient. Descriptive and multivariate inferential statistics were used for data analysis. Results Among the caregivers sampled, 87.3% had poor knowledge of positioning (mean score 14.9 ± 4.32). The mean score for FCAT was 49.7 ± 6.0 from a scale of 10 to 60. There was no significant association between knowledge on positioning and self-efficacy. Multiple linear regression showed that caregivers' age (B = 0.146, p = 0.003) and caregiver training (B = 3.302, p = 0.007) were independently associated with caregivers' self-efficacy. Conclusion Caregivers' knowledge on the positioning of stroke patients was poor, despite a fairly good level of self-efficacy. Older caregivers and receiving caregiver training were independently associated with better caregiver self-efficacy. This supports the provision of caregiver training to improve caregiver self-efficacy.

18.
Gastroenterology ; 157(6): 1615-1629.e17, 2019 12.
Article in English | MEDLINE | ID: mdl-31446059

ABSTRACT

BACKGROUND & AIMS: Some oncogenes encode transcription factors, but few drugs have been successfully developed to block their activity specifically in cancer cells. The transcription factor SALL4 is aberrantly expressed in solid tumor and leukemia cells. We developed a screen to identify compounds that reduce the viability of liver cancer cells that express high levels of SALL4, and we investigated their mechanisms. METHODS: We developed a stringent high-throughput screening platform comprising unmodified SNU-387 and SNU-398 liver cancer cell lines and SNU-387 cell lines engineered to express low and high levels of SALL4. We screened 1597 pharmacologically active small molecules and 21,575 natural product extracts from plant, bacteria, and fungal sources for those that selectively reduce the viability of cells with high levels of SALL4 (SALL4hi cells). We compared gene expression patterns of SALL4hi cells vs SALL4-knockdown cells using RNA sequencing and real-time polymerase chain reaction analyses. Xenograft tumors were grown in NOD/SCID gamma mice from SALL4hi SNU-398 or HCC26.1 cells or from SALL4lo patient-derived xenograft (PDX) cells; mice were given injections of identified compounds or sorafenib, and the effects on tumor growth were measured. RESULTS: Our screening identified 1 small molecule (PI-103) and 4 natural compound analogues (oligomycin, efrapeptin, antimycin, and leucinostatin) that selectively reduced viability of SALL4hi cells. We performed validation studies, and 4 of these compounds were found to inhibit oxidative phosphorylation. The adenosine triphosphate (ATP) synthase inhibitor oligomycin reduced the viability of SALL4hi hepatocellular carcinoma and non-small-cell lung cancer cell lines with minimal effects on SALL4lo cells. Oligomycin also reduced the growth of xenograft tumors grown from SALL4hi SNU-398 or HCC26.1 cells to a greater extent than sorafenib, but oligomycin had little effect on tumors grown from SALL4lo PDX cells. Oligomycin was not toxic to mice. Analyses of chromatin immunoprecipitation sequencing data showed that SALL4 binds approximately 50% of mitochondrial genes, including many oxidative phosphorylation genes, to activate their transcription. In comparing SALL4hi and SALL4-knockdown cells, we found SALL4 to increase oxidative phosphorylation, oxygen consumption rate, mitochondrial membrane potential, and use of oxidative phosphorylation-related metabolites to generate ATP. CONCLUSIONS: In a screening for compounds that reduce the viability of cells that express high levels of the transcription factor SALL4, we identified inhibitors of oxidative phosphorylation, which slowed the growth of xenograft tumors from SALL4hi cells in mice. SALL4 activates the transcription of genes that regulate oxidative phosphorylation to increase oxygen consumption, mitochondrial membrane potential, and ATP generation in cancer cells. Inhibitors of oxidative phosphorylation might be used for the treatment of liver tumors with high levels of SALL4.


Subject(s)
Antineoplastic Agents/pharmacology , High-Throughput Screening Assays/methods , Liver Neoplasms/drug therapy , Transcription Factors/antagonists & inhibitors , Animals , Antineoplastic Agents/therapeutic use , Cell Line, Tumor , Cell Survival/drug effects , Cell Survival/genetics , Female , Gene Expression Profiling , Gene Expression Regulation, Neoplastic/drug effects , Gene Knockdown Techniques , Humans , Liver Neoplasms/genetics , Liver Neoplasms/pathology , Male , Mice , Oxidative Phosphorylation/drug effects , Transcription Factors/genetics , Transcription Factors/metabolism , Up-Regulation/drug effects , Up-Regulation/genetics , Xenograft Model Antitumor Assays
19.
J Clin Mov Disord ; 6: 3, 2019.
Article in English | MEDLINE | ID: mdl-31367459

ABSTRACT

BACKGROUND: Huntington's disease (HD) is an autosomal dominant, neurodegenerative disorder. Associated cognitive deficits including impulsivity and disinhibition are the same factors that also predispose to forensic risk. Men tend to be perpetrators of more severe violent behaviours than women and women are less likely than men to be arrested for violence. This finding is not applicable in the case of women with Huntington's disease and explored in the three clinical cases of women with HD and their forensic histories that are subsequently described. CASE PRESENTATION: 'A' was admitted from court following a charge of arson and reckless behavior, with increasing severity and frequency of self-harm and attempted suicide. This case demonstrates someone who had previously presented to psychiatric services on multiple occasions for various reasons, culminating in a serious criminal charge of arson due to psychiatric symptoms associated with HD.'B' was arrested and imprisoned after having been charged with actual bodily harm (ABH) for assaulting her partner and young daughter then breaking her bail conditions. Although she was gene positive for HD she had no neurological symptoms of the disease. B was given leave but needed to be recalled to hospital by police. Six weeks later the medical recommendation for a court imposed hospital order was overturned as B presented and articulated her case so convincingly in court. This case demonstrates that even in the absence of psychiatric history or movement disorder there may be substantial forensic risk indicated by subtle underlying cognitive deficits due to changes in executive function affecting the frontal lobes.'C' was admitted to acute psychiatric services after being found wandering in traffic wanting to die. She had been diagnosed with HD in the previous year and had a long criminal record on a background of alcohol dependency. Following transfer to a specialist psychiatric unit, she engaged well with a neurobehavioural levels system which rewards desirable and appropriate behaviours and she responded well to a highly structured environment resulting in discharge to a community placement. CONCLUSIONS: These three case studies aim to highlight the need to raise awareness of the increased forensic risk in women with HD. Although criminal behaviour is less frequently observed in women than men and usually violence is less severe in women, HD may cause or contribute to criminal behaviour that can be violent in nature in women who are gene carriers for HD even in the absence of movement disorder, psychiatric symptoms or overt cognitive deficits. Assessment and earlier treatment in appropriate hospital settings may successfully contain and modify behaviours leading to reduced levels of risk and recidivism in this vulnerable patient group.

20.
Methods Mol Biol ; 2005: 43-66, 2019.
Article in English | MEDLINE | ID: mdl-31175645

ABSTRACT

Cancer stem cells (CSCs) are a subpopulation of cancer cells with self-renewal capacity, that fuel tumor growth and contribute to the heterogeneous nature of tumors. First identified in hematological malignancies, CSC populations have to date been proposed in solid tumors in various organs. In vitro and in vivo assays, mouse genetic models, and more recently single-cell sequencing technologies and other '-omics' methodologies have not only facilitated the identification of novel CSC populations but also revealed and clarified novel properties of CSCs. Increasingly, both cell-autonomous and CSC niche factors are recognized as important contributors of CSC properties. The deepened understanding of CSC properties and characteristics would enable and facilitate the rational design of CSC-specific therapeutics that would, ideally, have high selectivity for cancer cells, eliminate tumor bulk, and prevent tumor recurrence. Addressing these issues would form some of the key challenges of the CSC research field in the coming years.


Subject(s)
Neoplasms, Experimental , Neoplastic Stem Cells , Stem Cell Niche/genetics , Tumor Microenvironment/genetics , Animals , Humans , Mice , Neoplasms, Experimental/genetics , Neoplasms, Experimental/metabolism , Neoplasms, Experimental/pathology , Neoplasms, Experimental/therapy , Neoplastic Stem Cells/metabolism , Neoplastic Stem Cells/pathology
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