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1.
Nat Commun ; 15(1): 4096, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750019

RESUMO

The presence of heterogeneity in responses to oncolytic virotherapy poses a barrier to clinical effectiveness, as resistance to this treatment can occur through the inhibition of viral spread within the tumor, potentially leading to treatment failures. Here we show that 4-octyl itaconate (4-OI), a chemical derivative of the Krebs cycle-derived metabolite itaconate, enhances oncolytic virotherapy with VSVΔ51 in various models including human and murine resistant cancer cell lines, three-dimensional (3D) patient-derived colon tumoroids and organotypic brain tumor slices. Furthermore, 4-OI in combination with VSVΔ51 improves therapeutic outcomes in a resistant murine colon tumor model. Mechanistically, we find that 4-OI suppresses antiviral immunity in cancer cells through the modification of cysteine residues in MAVS and IKKß independently of the NRF2/KEAP1 axis. We propose that the combination of a metabolite-derived drug with an oncolytic virus agent can greatly improve anticancer therapeutic outcomes by direct interference with the type I IFN and NF-κB-mediated antiviral responses.


Assuntos
Terapia Viral Oncolítica , Vírus Oncolíticos , Succinatos , Animais , Humanos , Terapia Viral Oncolítica/métodos , Succinatos/farmacologia , Camundongos , Linhagem Celular Tumoral , Interferon Tipo I/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Neoplasias do Colo/terapia , Neoplasias do Colo/imunologia , Neoplasias do Colo/tratamento farmacológico , Antivirais/farmacologia , NF-kappa B/metabolismo , Quinase I-kappa B/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Inflamação/tratamento farmacológico , Feminino , Vírus da Estomatite Vesicular Indiana/fisiologia , Vírus da Estomatite Vesicular Indiana/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
2.
Neurooncol Adv ; 6(1): vdae032, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38560348

RESUMO

Tumor-treating fields (TTFields) are currently a Category 1A treatment recommendation by the US National Comprehensive Cancer Center for patients with newly diagnosed glioblastoma. Although the mechanism of action of TTFields has been partly elucidated, tangible and standardized metrics are lacking to assess antitumor dose and effects of the treatment. This paper outlines and evaluates the current standards and methodologies in the estimation of the TTFields distribution and dose measurement in the brain and highlights the most important principles governing TTFields dosimetry. The focus is on clinical utility to facilitate a practical understanding of these principles and how they can be used to guide treatment. The current evidence for a correlation between TTFields dose, tumor growth, and clinical outcome will be presented and discussed. Furthermore, we will provide perspectives and updated insights into the planning and optimization of TTFields therapy for glioblastoma by reviewing how the dose and thermal effects of TTFields are affected by factors such as tumor location and morphology, peritumoral edema, electrode array position, treatment duration (compliance), array "edge effect," electrical duty cycle, and skull-remodeling surgery. Finally, perspectives are provided on how to optimize the efficacy of future TTFields therapy.

3.
Invest New Drugs ; 42(2): 207-220, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38427117

RESUMO

It has previously been demonstrated that the polybisphosphonate osteodex (ODX) inhibits bone resorption in organ-cultured mouse calvarial bone. In this study, we further investigate the effects by ODX on osteoclast differentiation, formation, and function in several different bone organ and cell cultures. Zoledronic acid (ZOL) was used for comparison. In retinoid-stimulated mouse calvarial organ cultures, ODX and ZOL significantly reduced the numbers of periosteal osteoclasts without affecting Tnfsf11 or Tnfrsf11b mRNA expression. ODX and ZOL also drastically reduced the numbers of osteoclasts in cell cultures isolated from the calvarial bone and in vitamin D3-stimulated mouse crude bone marrow cell cultures. These data suggest that ODX can inhibit osteoclast formation by inhibiting the differentiation of osteoclast progenitor cells or by directly targeting mature osteoclasts. We therefore assessed if osteoclast formation in purified bone marrow macrophage cultures stimulated by RANKL was inhibited by ODX and ZOL and found that the initial formation of mature osteoclasts was not affected, but that the bisphosphonates enhanced cell death of mature osteoclasts. In agreement with these findings, ODX and ZOL did not affect the mRNA expression of the osteoclastic genes Acp5 and Ctsk and the osteoclastogenic transcription factor Nfatc1. When bone marrow macrophages were incubated on bone slices, ODX and ZOL inhibited RANKL-stimulated bone resorption. In conclusion, ODX does not inhibit osteoclast formation but inhibits osteoclastic bone resorption by decreasing osteoclast numbers through enhanced cell death of mature osteoclasts.


Assuntos
Reabsorção Óssea , Osteoclastos , Animais , Camundongos , Osteoclastos/metabolismo , Osteogênese , Medula Óssea , Células Cultivadas , Reabsorção Óssea/tratamento farmacológico , Reabsorção Óssea/metabolismo , Macrófagos/metabolismo , Diferenciação Celular , Morte Celular , Ácido Zoledrônico/farmacologia , Ácido Zoledrônico/metabolismo , RNA Mensageiro/metabolismo , Ligante RANK/farmacologia , Ligante RANK/metabolismo
4.
Proc Natl Acad Sci U S A ; 121(5): e2303513121, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38266046

RESUMO

Fibroblasts are essential regulators of extracellular matrix deposition following cardiac injury. These cells exhibit highly plastic responses in phenotype during fibrosis in response to environmental stimuli. Here, we test whether and how candidate anti-fibrotic drugs differentially regulate measures of cardiac fibroblast phenotype, which may help identify treatments for cardiac fibrosis. We conducted a high-content microscopy screen of human cardiac fibroblasts treated with 13 clinically relevant drugs in the context of TGFß and/or IL-1ß, measuring phenotype across 137 single-cell features. We used the phenotypic data from our high-content imaging to train a logic-based mechanistic machine learning model (LogiMML) for fibroblast signaling. The model predicted how pirfenidone and Src inhibitor WH-4-023 reduce actin filament assembly and actin-myosin stress fiber formation, respectively. Validating the LogiMML model prediction that PI3K partially mediates the effects of Src inhibition, we found that PI3K inhibition reduces actin-myosin stress fiber formation and procollagen I production in human cardiac fibroblasts. In this study, we establish a modeling approach combining the strengths of logic-based network models and regularized regression models. We apply this approach to predict mechanisms that mediate the differential effects of drugs on fibroblasts, revealing Src inhibition acting via PI3K as a potential therapy for cardiac fibrosis.


Assuntos
Actinas , Fibroblastos , Humanos , Aprendizado de Máquina , Fibrose , Miosinas , Fosfatidilinositol 3-Quinases
5.
Artigo em Inglês | MEDLINE | ID: mdl-38082495

RESUMO

OBJECTIVE: This is a secondary analysis of data from a previous study of anesthetized brain tumor patients receiving ephedrine or phenylephrine infusions. 18 patients with magnetic imaging verified tumor contrast enhancement were included. We hypothesized that vasopressors induce microcirculatory flow changes, characterized by increased capillary transit time heterogeneity (CTH) and decreased mean transit time (MTT), in brain regions exhibiting BBB leakage. METHODS: This is a secondary analysis of data from a previous study of anesthetized brain tumor patients receiving ephedrine or phenylephrine infusions. 18 patients with magnetic imaging verified tumor contrast enhancement were included. Postvasopressor to prevasopressor ratios of CTH, MTT, relative transit time heterogeneity (RTH), cerebral blood flow (CBF), cerebral blood volume, and oxygen extraction fraction (OEF) were calculated in tumor, peritumoral, hippocampal, and contralateral grey matter regions. Comparisons were made between brain regions and vasopressors. RESULTS: During phenylephrine infusion, ratios of CTH, RTH, and CBF were greater, and ratios of MTT and OEF were lower, in the tumor region with contrast leakage compared with corresponding contralateral grey matter ratios. During ephedrine infusion, ratios of CTH, MTT, RTH, CBF, and cerebral blood volume were higher in the tumor region with leakage compared with contralateral grey matter ratios. In addition, the ratio of CBF was higher in all regions, the ratio of RTH was lower in the leaking tumor region, and the ratio of OEF was lower in peritumoral, hippocampal, and grey matter regions with ephedrine compared with phenylephrine. CONCLUSIONS: Vasopressors can induce distinct microcirculatory flow alterations in regions with compromised brain tumor barrier or BBB. Ephedrine, a combined α and ß-adrenergic agonist, appears to result in fewer flow alterations and less impact on tissue oxygenation compared with phenylephrine, a pure α-adrenergic agonist.

6.
Obesity (Silver Spring) ; 31(9): 2249-2259, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37605636

RESUMO

OBJECTIVE: In the Semaglutide Treatment Effect in People with obesity (STEP) trials, once-weekly subcutaneous semaglutide 2.4 mg plus lifestyle intervention reduced body weight and improved cardiometabolic parameters in adults with obesity (or overweight with weight-related comorbidities). Effects on the risk of developing type 2 diabetes (T2D) require investigation. METHODS: STEP 1 (68 weeks) and 5 (104 weeks) randomized participants to semaglutide 2.4 mg or placebo. STEP 4 included a 20-week semaglutide run-in followed by randomization to 48 weeks of continued semaglutide or withdrawal (placebo). Ten-year T2D risk scores were calculated post hoc using Cardiometabolic Disease Staging. RESULTS: In STEP 1 (N = 1583), relative risk score reductions were greater with semaglutide versus placebo (semaglutide: -61.1%; placebo: -12.9%; p < 0.0001). These reductions were maintained to week 104 in STEP 5 (N = 295; semaglutide: -60.0%; placebo: 3.5%; p < 0.0001). Risk scores during the STEP 4 run-in period (N = 776) were reduced from 20.6% to 11.1% and further to 7.7% at week 68 with continued semaglutide, increasing to 15.4% with withdrawal (relative risk score change: semaglutide: -32.1%; placebo: +40.6%; p < 0.0001). Risk score reductions mirrored weight loss. CONCLUSIONS: Cardiometabolic Disease Staging risk assessment suggests that once-weekly semaglutide 2.4 mg may substantially lower 10-year T2D risk in people with overweight or obesity.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Adulto , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Obesidade/complicações , Obesidade/tratamento farmacológico , Sobrepeso/complicações , Sobrepeso/tratamento farmacológico
7.
Invest New Drugs ; 41(5): 688-698, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37556022

RESUMO

Medulloblastoma (MB) is the most common pediatric brain tumor. The therapy frequently causes serious side effects, and new selective therapies are needed. MB expresses hyper sialylation, a possible target for selective therapy. The cytotoxic efficacy of a poly guanidine conjugate (GuaDex) incubated with medulloblastoma cell cultures (DAOY and MB-LU-181) was investigated. The cells were incubated with 0.05-8 µM GuaDex from 15 min to 72 h. A fluorometric cytotoxicity assay (FMCA) measured the cytotoxicity. Labeled GuaDex was used to study tumor cell interaction. FITC-label Sambucus nigra confirmed high expression of sialic acid (Sia). Immunofluorescence microscopy was used to visualize the cell F-actin and microtubules. The cell interactions were studied by confocal and fluorescence microscopy. Annexin-V assay was used to detect apoptosis. Cell cycle analysis was done by DNA content determination. A wound-healing migration assay determined the effects on the migratory ability of DAOY cells after GuaDex treatment. IC50 for GuaDex was 223.4 -281.1 nM. FMCA showed potent growth inhibition on DAOY and MB-LU-181 cells at 5 uM GuaDex after 4 h of incubation. GuaDex treatment induced G2/M phase cell cycle arrest. S. nigra FITC-label lectin confirmed high expression of Sia on DAOY medulloblastoma cells. The GuaDex treatment polymerized the cytoskeleton (actin filaments and microtubules) and bound to DNA, inducing condensation. The Annexin V assay results were negative. Cell migration was inhibited at 0.5 µM GuaDex concentration after 24 h of incubation. GuaDex showed potent cytotoxicity and invasion-inhibitory effects on medulloblastoma cells at low micromolar concentrations. GuaDex efficacy was significant and warrants further studies.


Assuntos
Neoplasias Cerebelares , Meduloblastoma , Criança , Humanos , Meduloblastoma/tratamento farmacológico , Meduloblastoma/genética , Meduloblastoma/metabolismo , Guanidina/farmacologia , Guanidina/uso terapêutico , Fluoresceína-5-Isotiocianato/farmacologia , Fluoresceína-5-Isotiocianato/uso terapêutico , Proliferação de Células , Linhagem Celular Tumoral , Apoptose , Neoplasias Cerebelares/tratamento farmacológico , Neoplasias Cerebelares/metabolismo , Neoplasias Cerebelares/patologia , DNA
8.
Cogn Sci ; 47(6): e13308, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37354036

RESUMO

Rapid individual cognitive phenotyping holds the potential to revolutionize domains as wide-ranging as personalized learning, employment practices, and precision psychiatry. Going beyond limitations imposed by traditional lab-based experiments, new efforts have been underway toward greater ecological validity and participant diversity to capture the full range of individual differences in cognitive abilities and behaviors across the general population. Building on this, we developed Skill Lab, a novel game-based tool that simultaneously assesses a broad suite of cognitive abilities while providing an engaging narrative. Skill Lab consists of six mini-games as well as 14 established cognitive ability tasks. Using a popular citizen science platform (N = 10,725), we conducted a comprehensive validation in the wild of a game-based cognitive assessment suite. Based on the game and validation task data, we constructed reliable models to simultaneously predict eight cognitive abilities based on the users' in-game behavior. Follow-up validation tests revealed that the models can discriminate nuances contained within each separate cognitive ability as well as capture a shared main factor of generalized cognitive ability. Our game-based measures are five times faster to complete than the equivalent task-based measures and replicate previous findings on the decline of certain cognitive abilities with age in our large cross-sectional population sample (N = 6369). Taken together, our results demonstrate the feasibility of rapid in-the-wild systematic assessment of cognitive abilities as a promising first step toward population-scale benchmarking and individualized mental health diagnostics.


Assuntos
Jogos de Vídeo , Humanos , Estudos Transversais , Jogos de Vídeo/psicologia , Cognição , Aprendizagem , Aptidão
9.
Dan Med J ; 70(7)2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37381869

RESUMO

INTRODUCTION: The detection of incidental pancreatic cysts (PCs) is increasing due to frequent use of imaging. The aim of the present study was to evaluate the clinical consequences of regular multidisciplinary team (MDT) conferences for patients with PCs. METHODS: All patient data were obtained by review of patient medical records. PCs were assessed at the weekly MDT in accordance with the revised Fukuoka guidelines. RESULTS: A total of 455 patients were evaluated within 12 months. A large proportion of the cysts could not be characterised and was handled as branch duct (BD)-intraductal papillary mucinous neoplasia (IPMN). A total of 245 patients were included in a follow-up programme, whereas 175 patients were excluded. Further diagnostic work-up was recommended for 31 patients. A total of 66 patients were reviewed on MDT a second time during the study period, eight of whom received a diagnosis different from that given at the first MDT. A total of 35 patients with mucinous PC or cysts treated as BD-IPMN had either worrisome features (WF) or high-risk stigmata (HRS), four of these patients had a PC ≤ 10 mm. Indication for surgery was WF or HRS and, in the course of 12 months, six patients were recommended surgery taking their PS into account. Two patients had a malignant and two had a premalignant lesion. CONCLUSION: In all, 455 patients were evaluated to find 35 patients with suspected premalignant PCs. This means that almost 8% of the referred patients had suspicious lesions, which indicates a need for a regular MDT conference. FUNDING: None. TRIAL REGISTRATION: Not relevant.


Assuntos
Cisto Pancreático , Neoplasias Intraductais Pancreáticas , Neoplasias Pancreáticas , Humanos , Cisto Pancreático/diagnóstico por imagem , Prontuários Médicos , Neoplasias Pancreáticas/diagnóstico por imagem , Equipe de Assistência ao Paciente
10.
iScience ; 26(4): 106502, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37091233

RESUMO

RNA-binding protein muscleblind-like1 (MBNL1) was recently identified as a central regulator of cardiac wound healing and myofibroblast activation. To identify putative MBNL1 targets, we integrated multiple genome-wide screens with a fibroblast network model. We expanded the model to include putative MBNL1-target interactions and recapitulated published experimental results to validate new signaling modules. We prioritized 14 MBNL1 targets and developed novel fibroblast signaling modules for p38 MAPK, Hippo, Runx1, and Sox9 pathways. We experimentally validated MBNL1 regulation of p38 expression in mouse cardiac fibroblasts. Using the expanded fibroblast model, we predicted a hierarchy of MBNL1 regulated pathways with strong influence on αSMA expression. This study lays a foundation to explore the network mechanisms of MBNL1 signaling central to fibrosis.

11.
Chemosphere ; 329: 138646, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37037350

RESUMO

Electronic waste is a source of both legacy and emerging flame retardants to the environment, especially in regions where sufficient waste handling systems are lacking. In the present study, we quantified the occurrence of short- and medium chain chlorinated paraffins (SCCPs and MCCPs) and dechloranes in household chicken (Gallus domesticus) eggs and soil collected near waste disposal sites on Zanzibar and the Tanzanian mainland. Sampling locations included an e-waste facility and the active dumpsite of Dar es Salaam, a historical dumpsite in Dar es Salaam, and an informal dumpsite on Zanzibar. We compared concentrations and contaminant profiles between soil and eggs, as free-range chickens ingest a considerable amount of soil during foraging, with potential for maternal transfer to the eggs. We found no correlation between soil and egg concentrations or patterns of dechloranes or CPs. CPs with shorter chain lengths and higher chlorination degree were associated with soil, while longer chain lengths and lower chlorination degree were associated with eggs. MCCPs dominated the CP profile in eggs, with median concentrations ranging from 500 to 900 ng/g lipid weight (lw) among locations. SCCP concentrations in eggs ranged from below the detection limit (LOD) to 370 ng/g lw. Dechlorane Plus was the dominating dechlorane compound in all egg samples, with median concentrations ranging from 0.5 to 2.8 ng/g lw. SCCPs dominated in the soil samples (400-21300 ng/g soil organic matter, SOM), except at the official dumpsite where MCCPs were highest (65000 ng/g SOM). Concentrations of dechloranes in soil ranged from below LOD to 240 ng/g SOM, and the dominating compounds were Dechlorane Plus and Dechlorane 603. Risk assessment of CP levels gave margins of exposure (MOE) close to or below 1000 for SCCPs at one location.


Assuntos
Galinhas , Hidrocarbonetos Clorados , Animais , Tanzânia , Parafina/análise , Solo , Monitoramento Ambiental , Hidrocarbonetos Clorados/análise , Instalações de Eliminação de Resíduos , China
12.
PLoS Genet ; 19(4): e1010724, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37068079

RESUMO

The biochemical pathway regulating the synthesis of yellow/red pheomelanin is less well characterized than the synthesis of black/brown eumelanin. Inhibitor of gold (IG phenotype) is a plumage colour variant in chicken that provides an opportunity to further explore this pathway since the recessive allele (IG) at this locus is associated with a defect in the production of pheomelanin. IG/IG homozygotes display a marked dilution of red pheomelanin pigmentation, whilst black pigmentation (eumelanin) is only slightly affected. Here we show that a 2-base pair insertion (frame-shift mutation) in the 5th exon of the Catechol-O-methyltransferase containing domain 1 gene (COMTD1), expected to cause a complete or partial loss-of-function of the COMTD1 enzyme, shows complete concordance with the IG phenotype within and across breeds. We show that the COMTD1 protein is localized to mitochondria in pigment cells. Knockout of Comtd1 in a mouse melanocytic cell line results in a reduction in pheomelanin metabolites and significant alterations in metabolites of glutamate/glutathione, riboflavin, and the tricarboxylic acid cycle. Furthermore, COMTD1 overexpression enhanced cellular proliferation following chemical-induced transfection, a potential inducer of oxidative stress. These observations suggest that COMTD1 plays a protective role for melanocytes against oxidative stress and that this supports their ability to produce pheomelanin.


Assuntos
Catecol O-Metiltransferase , Galinhas , Camundongos , Animais , Galinhas/genética , Catecol O-Metiltransferase/genética , Camundongos Knockout , Melaninas/metabolismo , Pigmentação/genética , Mutação da Fase de Leitura
13.
bioRxiv ; 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-36909540

RESUMO

Fibroblasts are essential regulators of extracellular matrix deposition following cardiac injury. These cells exhibit highly plastic responses in phenotype during fibrosis in response to environmental stimuli. Here, we test whether and how candidate anti-fibrotic drugs differentially regulate measures of cardiac fibroblast phenotype, which may help identify treatments for cardiac fibrosis. We conducted a high content microscopy screen of human cardiac fibroblasts treated with 13 clinically relevant drugs in the context of TGFß and/or IL-1ß, measuring phenotype across 137 single-cell features. We used the phenotypic data from our high content imaging to train a logic-based mechanistic machine learning model (LogiMML) for fibroblast signaling. The model predicted how pirfenidone and Src inhibitor WH-4-023 reduce actin filament assembly and actin-myosin stress fiber formation, respectively. Validating the LogiMML model prediction that PI3K partially mediates the effects of Src inhibition, we found that PI3K inhibition reduces actin-myosin stress fiber formation and procollagen I production in human cardiac fibroblasts. In this study, we establish a modeling approach combining the strengths of logic-based network models and regularized regression models, apply this approach to predict mechanisms that mediate the differential effects of drugs on fibroblasts, revealing Src inhibition acting via PI3K as a potential therapy for cardiac fibrosis.

14.
Anal Chem ; 95(7): 3720-3728, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36757324

RESUMO

Current techniques for monitoring disease progression and testing drug efficacy in animal models of inflammatory arthritis are either destructive, time-consuming, subjective, or require ionizing radiation. To accommodate this, we have developed a non-invasive and label-free optical system based on Raman spectroscopy for monitoring tissue alterations in rodent models of arthritis at the biomolecular level. To test different sampling geometries, the system was designed to collect both transmission and reflection mode spectra. Mice with collagen antibody-induced arthritis and controls were subject to in vivo Raman spectroscopy at the tibiotarsal joint every 3 days for 14 days. Raman-derived measures of bone content correlated well with micro-computed tomography bone mineral densities. This allowed for time-resolved quantitation of bone densities, which indicated gradual bone erosion in mice with arthritis. Inflammatory pannus formation, bone erosion, and bone marrow inflammation were confirmed by histological analysis. In addition, using library-based spectral decomposition, we quantified the progression of bone and soft tissue components. In general, the tissue components followed significantly different tendencies in mice developing arthritis compared to the control group in line with the histological analysis. In total, this demonstrates Raman spectroscopy as a versatile technique for monitoring alterations to both mineralized and soft tissues simultaneously in rodent models of musculoskeletal disorders. Furthermore, the technique presented herein allows for objective repeated within-animal measurements potentially refining and reducing the use of animals in research while improving the development of novel antiarthritic therapeutics.


Assuntos
Artrite , Análise Espectral Raman , Camundongos , Animais , Microtomografia por Raio-X/métodos , Análise Espectral Raman/métodos , Modelos Animais , Progressão da Doença , Modelos Animais de Doenças
15.
Nucleic Acids Res ; 51(4): 1766-1782, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36762476

RESUMO

In Escherichia coli, replication of both strands of genomic DNA is carried out by a single replicase-DNA polymerase III holoenzyme (pol III HE). However, in certain genetic backgrounds, the low-fidelity TLS polymerase, DNA polymerase V (pol V) gains access to undamaged genomic DNA where it promotes elevated levels of spontaneous mutagenesis preferentially on the lagging strand. We employed active site mutants of pol III (pol IIIα_S759N) and pol V (pol V_Y11A) to analyze ribonucleotide incorporation and removal from the E. coli chromosome on a genome-wide scale under conditions of normal replication, as well as SOS induction. Using a variety of methods tuned to the specific properties of these polymerases (analysis of lacI mutational spectra, lacZ reversion assay, HydEn-seq, alkaline gel electrophoresis), we present evidence that repair of ribonucleotides from both DNA strands in E. coli is unequal. While RNase HII plays a primary role in leading-strand Ribonucleotide Excision Repair (RER), the lagging strand is subject to other repair systems (RNase HI and under conditions of SOS activation also Nucleotide Excision Repair). Importantly, we suggest that RNase HI activity can also influence the repair of single ribonucleotides incorporated by the replicase pol III HE into the lagging strand.


Assuntos
Reparo do DNA , Escherichia coli , DNA Polimerase III/genética , Replicação do DNA , Escherichia coli/genética , Ribonucleotídeos/metabolismo
16.
Methods Mol Biol ; 2615: 315-325, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36807801

RESUMO

Here, we describe an assay that enables mapping of 5'-ends across the genome using next-generation sequencing on an Illumina platform, 5'-End-sequencing (5'-End-seq). We use this method to map free 5'-ends in mtDNA isolated from fibroblasts. This method can be used to answer key questions regarding DNA integrity, DNA replication mechanisms and to identify priming events, primer processing, nick processing, and double strand break processing on the entire genome.


Assuntos
DNA Mitocondrial , Mitocôndrias , Humanos , DNA Mitocondrial/genética , Mitocôndrias/genética , Replicação do DNA , Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência de DNA
17.
Lancet Glob Health ; 11(2): e287-e295, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36669809

RESUMO

BACKGROUND: Primary postpartum haemorrhage is the principal cause of birth-related maternal mortality in most settings and has remained persistently high in severely resource-constrained countries. We evaluate the impact of an intervention that aims to halve maternal mortality caused by primary postpartum haemorrhage within 2 years, nationwide in Niger. METHODS: In this 72-month longitudinal study, we analysed the effects of a primary postpartum haemorrhage intervention in hospitals and health centres in Niger, using data on maternal birth outcomes assessed and recorded by the facilities' health professionals and reported once per month at the national level. Reported data were monitored, compiled, and analysed by a non-governmental organisation collaborating with the Ministry of Health. All births in all health facilities in which births occurred, nationwide, were included, with no exclusion criteria. After a preintervention survey, brief training, and supplies distribution, Niger implemented a nationwide primary postpartum haemorrhage prevention and three-step treatment strategy using misoprostol, followed if needed by an intrauterine condom tamponade, and a non-inflatable anti-shock garment, with a specific set of organisational public health tools, aiming to reduce primary postpartum haemorrhage mortality. FINDINGS: Among 5 382 488 expected births, 2 254 885 (41·9%) occurred in health facilities, of which information was available on 1 380 779 births from Jan 1, 2015, to Dec 31, 2020, with reporting increasing considerably over time. Primary postpartum mortality decreased from 82 (32·16%; 95% CI 25·58-39·92) of 255 health facility maternal deaths in the 2013 preintervention survey to 146 (9·53%; 8·05-11·21) of 1532 deaths among 343 668 births in 2020. Primary postpartum haemorrhage incidence varied between 1900 (2·10%; 2·01-2·20) of 90 453 births and 4758 (1·47%; 1·43-1·52) of 322 859 births during 2015-20, an annual trend of 0·98 (95% CI 0·97-0·99; p<0·0001). INTERPRETATION: Primary postpartum haemorrhage morbidity and mortality declined rapidly nationwide. Because each treatment technology that was used has shown some efficacy when used alone, a strategic combination of these treatments can reasonably attain outcomes of this magnitude. Niger's strategy warrants testing in other low-income and perhaps some middle-income settings. FUNDING: The Government of Norway, the Government of Niger, the Kavli Trust (Kavlifondet), the InFiL Foundation, and individuals in Norway, the UK, and the USA. TRANSLATION: For the French translation of the abstract see Supplementary Materials section.


Assuntos
Hemorragia Pós-Parto , Feminino , Humanos , Hemorragia Pós-Parto/epidemiologia , Hemorragia Pós-Parto/prevenção & controle , Níger/epidemiologia , Estudos Longitudinais , Período Periparto , Instalações de Saúde
18.
J Orthop Res ; 41(7): 1407-1418, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36370134

RESUMO

This study aims to develop a comprehensive and easily executable histopathologic grading scheme for murine knee osteoarthritis (OA) using specific scoring criteria for both cartilage and periarticular changes, which may overcome important limitations of the existing grading systems. The new grading scheme was developed based on mouse knee OA models with observation periods up to 24 months of age (spontaneous OA) or 24-week post-injury (posttraumatic OA). Semi-quantitative assessments of the histopathologic OA changes were applied to all four quadrants per femorotibial joint for 50 joints (200 quadrants) using specific scoring criteria rather than mild to severe grades. Scoring elements per quadrant were as follows: cartilage lesion (0-7), osteophyte (0-3), subchondral bone change (0-3), synovitis (0-3), and ectopic periarticular soft-tissue chondrogenesis and ossification (0-3). The new histopathologic grading scheme had high intra- and interobserver reproducibility (correlation coefficients r > 0.95) across experienced and novice observers. Sensitivity and reliability analyses confirmed the ability of the new scheme to detect minimal but significant OA progression (p < 0.01) within a 2-week interval and to accurately identify tissue- and quadrant-specific OA severity within the joints. In conclusion, this study presents the first whole-joint histopathologic grading scheme for murine knee OA that covers all-stage osteoarthritic changes in all major joint tissues, including periarticular soft-tissue ossification that is not included in any of the existing OA grading systems. This reproducible scheme is easy to execute and sensitive to minimal OA progression without using computer software, suitable for quick OA severity assessments of the entire femorotibial joint.


Assuntos
Cartilagem Articular , Osteoartrite do Joelho , Osteófito , Camundongos , Animais , Osteoartrite do Joelho/patologia , Reprodutibilidade dos Testes , Articulação do Joelho/patologia , Cartilagem/patologia , Osteófito/patologia , Cartilagem Articular/patologia
19.
Open Res Eur ; 3: 82, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38778904

RESUMO

Farmers, veterinarians and other animal health managers in the livestock sector are currently missing sufficient information on prevalence and burden of contagious endemic animal diseases. They need adequate tools for risk assessment and prioritization of control measures for these diseases. The DECIDE project develops data-driven decision-support tools, which present (i) robust and early signals of disease emergence and options for diagnostic confirmation; and (ii) options for controlling the disease along with their implications in terms of disease spread, economic burden and animal welfare. DECIDE focuses on respiratory and gastro-intestinal syndromes in the three most important terrestrial livestock species (pigs, poultry, cattle) and on reduced growth and mortality in two of the most important aquaculture species (salmon and trout). For each of these, we (i) identify the stakeholder needs; (ii) determine the burden of disease and costs of control measures; (iii) develop data sharing frameworks based on federated data access and meta-information sharing; (iv) build multivariate and multi-level models for creating early warning systems; and (v) rank interventions based on multiple criteria. Together, all of this forms decision-support tools to be integrated in existing farm management systems wherever possible and to be evaluated in several pilot implementations in farms across Europe. The results of DECIDE lead to improved use of surveillance data and evidence-based decisions on disease control. Improved disease control is essential for a sustainable food chain in Europe with increased animal health and welfare and that protects human health.

20.
Nucleic Acids Res ; 50(15): 8749-8766, 2022 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-35947649

RESUMO

The in vivo role for RNase H1 in mammalian mitochondria has been much debated. Loss of RNase H1 is embryonic lethal and to further study its role in mtDNA expression we characterized a conditional knockout of Rnaseh1 in mouse heart. We report that RNase H1 is essential for processing of RNA primers to allow site-specific initiation of mtDNA replication. Without RNase H1, the RNA:DNA hybrids at the replication origins are not processed and mtDNA replication is initiated at non-canonical sites and becomes impaired. Importantly, RNase H1 is also needed for replication completion and in its absence linear deleted mtDNA molecules extending between the two origins of mtDNA replication are formed accompanied by mtDNA depletion. The steady-state levels of mitochondrial transcripts follow the levels of mtDNA, and RNA processing is not altered in the absence of RNase H1. Finally, we report the first patient with a homozygous pathogenic mutation in the hybrid-binding domain of RNase H1 causing impaired mtDNA replication. In contrast to catalytically inactive variants of RNase H1, this mutant version has enhanced enzyme activity but shows impaired primer formation. This finding shows that the RNase H1 activity must be strictly controlled to allow proper regulation of mtDNA replication.


Assuntos
DNA Mitocondrial , Ribonuclease H , Camundongos , Animais , DNA Mitocondrial/química , Ribonuclease H/genética , Ribonuclease H/metabolismo , RNA/química , Replicação do DNA/genética , Mitocôndrias/genética , Mamíferos/genética
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