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1.
Nat Mater ; 23(3): 429-438, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38361041

RESUMO

Cancer cell glycocalyx is a major line of defence against immune surveillance. However, how specific physical properties of the glycocalyx are regulated on a molecular level, contribute to immune evasion and may be overcome through immunoengineering must be resolved. Here we report how cancer-associated mucins and their glycosylation contribute to the nanoscale material thickness of the glycocalyx and consequently modulate the functional interactions with cytotoxic immune cells. Natural-killer-cell-mediated cytotoxicity is inversely correlated with the glycocalyx thickness of the target cells. Changes in glycocalyx thickness of approximately 10 nm can alter the susceptibility to immune cell attack. Enhanced stimulation of natural killer and T cells through equipment with chimeric antigen receptors can improve the cytotoxicity against mucin-bearing target cells. Alternatively, cytotoxicity can be enhanced through engineering effector cells to display glycocalyx-editing enzymes, including mucinases and sialidases. Together, our results motivate the development of immunoengineering strategies that overcome the glycocalyx armour of cancer cells.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Glicocálix/metabolismo , Mucinas/metabolismo , Antineoplásicos/metabolismo , Neoplasias/terapia
2.
Entropy (Basel) ; 26(2)2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38392381

RESUMO

Spiking neural networks (SNNs) are recurrent models that can leverage sparsity in input time series to efficiently carry out tasks such as classification. Additional efficiency gains can be obtained if decisions are taken as early as possible as a function of the complexity of the input time series. The decision on when to stop inference and produce a decision must rely on an estimate of the current accuracy of the decision. Prior work demonstrated the use of conformal prediction (CP) as a principled way to quantify uncertainty and support adaptive-latency decisions in SNNs. In this paper, we propose to enhance the uncertainty quantification capabilities of SNNs by implementing ensemble models for the purpose of improving the reliability of stopping decisions. Intuitively, an ensemble of multiple models can decide when to stop more reliably by selecting times at which most models agree that the current accuracy level is sufficient. The proposed method relies on different forms of information pooling from ensemble models and offers theoretical reliability guarantees. We specifically show that variational inference-based ensembles with p-variable pooling significantly reduce the average latency of state-of-the-art methods while maintaining reliability guarantees.

3.
Sci Rep ; 14(1): 18888, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39143179

RESUMO

This paper presents a Cosine Similarity-Based Knowledge Distillation (CSKD) for robust, lightweight object detectors. Knowledge Distillation (KD) has been effective in enhancing the performance of compact models in image classification by leveraging deep CNN models. However, the complex and multifaceted nature of object detection, characterized by its modular design and multitasking requirements, poses significant challenges for traditional KD techniques. These challenges are further compounded by the conventional reliance on the Mean Squared Error (MSE) loss function and the limited application of enhanced feature representations to the training phase. Addressing these limitations, the proposed CSKD method combines cosine similarity guidance with MSE loss to facilitate a more effective knowledge transfer from the teacher model to the student model. This is achieved by distilling both intermediate features and prediction outputs, aided by an assistant prediction branch designed to learn directly from the teacher's predictions. This dual-faceted distillation strategy enables the student model to better mimic the teacher model's behavior, leading to improved performance. The proposed method demonstrates versatility and robustness across various object detector architectures without the need for additional feature enhancement layers during training. Notably, employing ResNet-50 as the teacher model and ResNet-18 as the student model, we achieve new benchmarks in KD for object detection across several architectures, including Faster-RCNN, RetinaNet, FCOS, and GFL, with respective mAP scores of 36.6, 35.2, 35.9, and 38.9. These results highlights the effectiveness of CSKD in advancing the state-of-the-art in KD for object detection, offering a compelling solution to the challenges previously faced by traditional KD methods in this domain. The code of the proposed CSKD is available at https://github.com/swkdn16/CSKD .

4.
ESC Heart Fail ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39015043

RESUMO

AIMS: Both patients with heart failure (HF) with reduced ejection fraction (HFrEF) and those with HF with preserved ejection fraction (HFpEF) present with elevated N-terminal pro-brain natriuretic peptide (NT-proBNP) and have multiple comorbidities; consequently, the prognostic effect of NT-proBNP according to beta-blocker (BB) use is unknown. METHODS: This retrospective study evaluated patients admitted for acute HF between January 2012 and December 2017 at Ulsan University Hospital. Clinical, echocardiographic, laboratory and drug prescription data, including BB data, were collected from the hospital database. Information on mortality was collected by reviewing medical records or using national death data. RESULTS: Of the 472 patients evaluated, 216 (45.8%) and 256 (54.2%) patients were and were not prescribed BB at discharge, respectively. A total of 224 (47.5%) patients died within a median follow-up duration of 44 months. The Kaplan-Meier analysis showed reduced all-cause mortality with BB in HFrEF (ejection fraction ≤ 40%) but not in HFpEF (ejection fraction > 40%). In the multivariate Cox regression analysis, transmitral to tissue Doppler imaging, early diastolic velocity ratio (E/E'), NT-proBNP and BB use were independent predictors of all-cause mortality in HFrEF. Meanwhile, haemoglobin and NT-proBNP levels were independent predictors of HFpEF. The NT-proBNP cut-off value for determining all-cause mortality was set to 4800 pg/mL. Among HFrEF patients with NT-proBNP < 4800 pg/mL, the survival rate was higher for patients with BB use than those with no BB use (log-rank P < 0.001). However, in the HFpEF group, the survival rate associated with BB use did not differ according to the NT-proBNP levels. Both HFrEF and HFpEF patients with NT-proBNP levels of ≥4800 pg/mL presented with multiple comorbidities, including lower body mass index and haemoglobin levels and higher creatinine levels, NT-proBNP levels and E/E'. CONCLUSION: In patients with acute HF, BB use is associated with reduced all-cause mortality in those with HFrEF but not in those with HFpEF. HFrEF patients with NT-proBNP levels of <4800 pg/mL treated with BB have a higher survival rate than those not treated with BB. However, this benefit is not seen in HFrEF patients with NT-proBNP levels of ≥4800 pg/mL or in all HFpEF patients, regardless of the NT-proBNP level. NT-proBNP levels are elevated in multiple comorbid conditions, and these comorbidities may contribute to the attenuated effects of BB on all-cause mortality.

5.
Mol Biol Cell ; : mbcE24050218, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39110529

RESUMO

Genetic, colocalization, and biochemical studies suggest that the ankyrin repeat-containing proteins Inversin (INVS) and ANKS6 function with the NEK8 kinase to control tissue patterning and maintain organ physiology. It is unknown whether these three proteins assemble into a static "Inversin complex" or one that adopts multiple bioactive forms. Through characterization of hyperactive alleles in C. elegans, we discovered that the Inversin complex is activated by dimerization. Genome engineering of an RFP tag onto the nematode homologues of INVS (MLT-4) and NEK8 (NEKL-2) induced a gain-of-function, cyst-like phenotype that was suppressed by monomerization of the fluorescent tag. Stimulated dimerization of MLT-4 or NEKL-2 using optogenetics was sufficient to recapitulate the phenotype of a constitutively active Inversin complex. Further, dimerization of NEKL-2 bypassed a lethal MLT-4 mutant, demonstrating that the dimeric form is required for function. We propose that dynamic switching between at least two functionally distinct states--an active dimer and an inactive monomer--gates the output of the Inversin complex.

6.
Adv Mater ; : e2311505, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38279892

RESUMO

Skeletal metastasis is common in patients with advanced breast cancer and often caused by immune evasion of disseminated tumor cells (DTCs). In the skeleton, tumor cells not only disseminate to the bone marrow but also to osteogenic niches in which they interact with newly mineralizing bone extracellular matrix (ECM). However, it remains unclear how mineralization of collagen type I, the primary component of bone ECM, regulates tumor-immune cell interactions. Here, a combination of synthetic bone matrix models with controlled mineral content, nanoscale optical imaging, and flow cytometry are utilized to evaluate how collagen type I mineralization affects the biochemical and biophysical properties of the tumor cell glycocalyx, a dense layer of glycosylated proteins and lipids decorating their cell surface. These results suggest that collagen mineralization upregulates mucin-type O-glycosylation and sialylation by tumor cells, which increases their glycocalyx thickness while enhancing resistance to attack by natural killer (NK) cells. These changes are functionally linked as treatment with a sialylation inhibitor decreased mineralization-dependent glycocalyx thickness and made tumor cells more susceptible to NK cell attack. Together, these results suggest that interference with glycocalyx sialylation may represent a therapeutic strategy to enhance cancer immunotherapies targeting bone-metastatic breast cancer.

7.
bioRxiv ; 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38328161

RESUMO

Skeletal metastasis is common in patients with advanced breast cancer, and often caused by immune evasion of disseminated tumor cells (DTCs). In the skeleton, tumor cells not only disseminate to the bone marrow, but also to osteogenic niches in which they interact with newly mineralizing bone extracellular matrix (ECM). However, it remains unclear how mineralization of collagen type I, the primary component of bone ECM, regulates tumor-immune cell interactions. Here, we have utilized a combination of synthetic bone matrix models with controlled mineral content, nanoscale optical imaging, and flow cytometry to evaluate how collagen type I mineralization affects the biochemical and biophysical properties of the tumor cell glycocalyx, a dense layer of glycosylated proteins and lipids decorating their cell surface. Our results suggest that collagen mineralization upregulates mucin-type O-glycosylation and sialylation by tumor cells, which increased their glycocalyx thickness while enhancing resistance to attack by Natural Killer (NK) cells. These changes were functionally linked as treatment with a sialylation inhibitor decreased mineralization-dependent glycocalyx thickness and made tumor cells more susceptible to NK cell attack. Together, our results suggest that interference with glycocalyx sialylation may represent a therapeutic strategy to enhance cancer immunotherapies targeting bone-metastatic breast cancer.

8.
Medicine (Baltimore) ; 103(31): e39121, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39093769

RESUMO

RATIONALE: Depression is a common symptom in post-coronavirus disease 2019 (COVID-19) patients, which can be diagnosed with post-COVID-19 depression or adjustment disorder (AD) of post-COVID-19 syndrome. Recently, there have been reports of treating post-COVID-19 syndrome with herbal interventions. However, there are no studies of AD of post-COVID-19 syndrome treated with an integrative approach. This is a CARE-compliant case report of a patient diagnosed with AD of post-COVID-19 syndrome and improved with integrative personalized medicine care (IPMC). PATIENT CONCERNS: An 84-year-old female patient presented symptoms of depression, insomnia, palpitations, and dyspepsia after COVID-19 diagnosis. DIAGNOSES: The patient was diagnosed with AD due to COVID-19 according to Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition. INTERVENTIONS: The patient was treated with the IPMC approach: conventional Western drugs for symptom improvements with herbal medicine, acupuncture, and moxibustion therapies of traditional Korean medicine to enhance her general conditions. OUTCOMES: Depression, insomnia, palpitations, dyspepsia, and overall quality of life were assessed through various questionnaires before and after treatment. Scores notably decreased across depression scales, and insomnia severity improved significantly. After treatment, gastrointestinal symptoms vanished, and autonomic nervous system balance improved. Quality of life metrics also showed remarkable enhancement. LESSONS: This study is the first case report to demonstrate improvement in AD of post-COVID-19 symptoms using IPMC. It is noteworthy that the patient in this study tapered off their antidepressant medication after the treatment with the IPMC approach. Further studies are needed to establish more qualified evidence to show the effectiveness and safety of IPMC for AD of post-COVID-19 syndrome.


Assuntos
COVID-19 , Medicina de Precisão , Humanos , Feminino , COVID-19/complicações , COVID-19/terapia , COVID-19/psicologia , Idoso de 80 Anos ou mais , Medicina de Precisão/métodos , Transtornos de Adaptação/terapia , Medicina Integrativa/métodos , SARS-CoV-2 , Medicina Tradicional Coreana , Depressão/terapia , Depressão/etiologia , Distúrbios do Início e da Manutenção do Sono/terapia , Distúrbios do Início e da Manutenção do Sono/etiologia , Qualidade de Vida
9.
bioRxiv ; 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38798613

RESUMO

Genetic, colocalization, and biochemical studies suggest that the ankyrin repeat-containing proteins Inversin (INVS) and ANKS6 function with the NEK8 kinase to control tissue patterning and maintain organ physiology. It is unknown whether these three proteins assemble into a static "Inversin complex" or one that adopts multiple bioactive forms. Through characterization of hyperactive alleles in C. elegans , we discovered that the Inversin complex is activated by dimerization. Genome engineering of an RFP tag onto the nematode homologs of INVS (MLT-4) and NEK8 (NEKL-2) induced a gain-of-function, cyst-like phenotype that was suppressed by monomerization of the fluorescent tag. Stimulated dimerization of MLT-4 or NEKL-2 using optogenetics was sufficient to recapitulate the phenotype of a constitutively active Inversin complex. Further, dimerization of NEKL-2 bypassed a lethal MLT-4 mutant, demonstrating that the dimeric form is required for function. We propose that dynamic switching between at least two functionally distinct states-an active dimer and an inactive monomer-gates the output of the Inversin complex.

10.
ACS Omega ; 9(8): 9432-9442, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38434861

RESUMO

In this study, production and isolation of glucaric acid from lignocellulosic biomass were performed via potassium cation-based TEMPO-mediated oxidation for the ease of glucaric acid isolation. To optimize the oxidation conditions, response surface methodology (RSM) was adopted using standard glucose as the raw material. Among the oxidation conditions, the dosage of oxidant and pH of reaction affected the glucaric acid production, and the optimum conditions were suggested by RSM analysis: 5 °C of reaction temperature, 4.23 equiv dosage of KClO per mole of glucose, and pH of 12. Furthermore, glucaric acid was produced from lignocellulosic biomass-derived enzymatic hydrolysate from Miscanthus under optimum conditions. The impurities such as xylose and lignin in enzymatic hydrolysate inhibited the efficiency of glucose oxidation. As a result, more oxidant was required to produce sufficient glucaric acid from the enzymatic hydrolysate compared to standard glucose. The produced glucaric acid was simply isolated by controlling the pH in the form of glucaric acid monopotassium salt, which showed lower solubility in water, and the purity of isolated glucaric acid was over 99%. The overall mass balance of feedstock to glucaric acid was analyzed, suggesting that 86.38% (w/w) glucaric acid could be produced from initial glucan in feedstock.

11.
J Anim Sci Technol ; 66(3): 514-522, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38975584

RESUMO

This study mainly evaluated the responses in growth performance of growing pigs to different energy systems and energy levels in diets. Subsequently, we compared the nutrient digestibility and digestible nutrient concentrations of each energy level diet. In experiment 1, a total of 144 growing pigs with an average initial body weight (BW) of 26.69 ± 7.39 kg were randomly allotted to six dietary treatments (four pigs/pen; six replicates/treatment) according to a 2 × 3 factorial arrangement resulting from two energy systems (metabolizable energy [ME] and net energy [NE]) and three energy levels (low [LE], recommended [C], and high energy [HE]). Pigs were fed the experimental diets for 6 weeks and were allowed free access to feed and water during the experimental period. In experiment 2, 12 growing pigs with an average initial BW of 27.0 ± 1.8 kg were randomly allotted to individual metabolism crates and fed the six diets in a replicated 6 × 6 Latin square design. The six dietary treatments were identical to those used in the growth trial. Pigs were fed their respective diets at 2.5 times the estimated energy requirement for maintenance per day, and this was divided into two equal meals provided twice per day during the experimental period. Differences in energy systems and energy levels had no significant effect on the growth performance or nutrient digestibility (except acid-hydrolyzed ether extract [AEE]) of growing pigs in the current study. However, the digestible concentrations of ether extract, AEE, and acid detergent fiber (g/kg dry matter [DM]) in diets significantly increased (p < 0.05) with increasing energy levels. Additionally, there was a tendency (p = 0.09) for an increase in the digestible crude protein content (g/kg DM) as the energy content of the diet increased. Consequently, differences in energy systems and levels did not affect the BW, average daily gain, and average daily feed intake of growing pigs. This implies that a higher variation in dietary energy levels may be required to significantly affect growth performance and nutrient digestibility when considering digestible nutrient concentrations.

12.
Sci Rep ; 14(1): 14679, 2024 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-38918543

RESUMO

In Asian patients with atrial fibrillation (AF) and end-stage renal disease (ESRD) undergoing dialysis, the use of direct oral anticoagulants (DOACs) remains debatable. From the national health insurance claims data in South Korea, we included 425 new users of OAC among patients with non-valvular AF and ESRD undergoing dialysis between 2013 and 2020. Patients were categorized into DOAC (n = 106) and warfarin group (n = 319). Clinical outcomes, including ischemic stroke, myocardial infarction (MI), intracranial hemorrhage (ICH), and gastrointestinal (GI) bleeding, were compared between the two groups using inverse probability of treatment weighting (IPTW) analysis. During the median follow-up of 3.2 years, the incidence of ischemic stroke was significantly reduced in the DOAC compared to the warfarin group [Hazard ratio (HR) 0.07; P = 0.001]. However, the incidence of MI (HR 1.32; P = 0.41) and GI bleeding (HR 1.78; P = 0.06) were not significantly different between the two groups. No ICH events occurred in the DOAC group, although the incidence rate did not differ significantly between the two groups (P = 0.17). In Asian patients with AF and ESRD undergoing dialysis, DOACs may be associated with a reduced risk of ischemic stroke compared with warfarin. The MI, ICH, and GI bleeding rates may be comparable between DOACs and warfarin.


Assuntos
Anticoagulantes , Fibrilação Atrial , Falência Renal Crônica , Diálise Renal , Varfarina , Humanos , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/complicações , Falência Renal Crônica/terapia , Falência Renal Crônica/complicações , Masculino , Feminino , Diálise Renal/efeitos adversos , Idoso , Anticoagulantes/uso terapêutico , Anticoagulantes/administração & dosagem , Anticoagulantes/efeitos adversos , Varfarina/uso terapêutico , Varfarina/efeitos adversos , Varfarina/administração & dosagem , Administração Oral , Pessoa de Meia-Idade , República da Coreia/epidemiologia , Incidência , Povo Asiático , Hemorragia Gastrointestinal/epidemiologia , Hemorragia Gastrointestinal/etiologia , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/etiologia , AVC Isquêmico/epidemiologia , AVC Isquêmico/etiologia , AVC Isquêmico/prevenção & controle , Idoso de 80 Anos ou mais
13.
Sci Rep ; 14(1): 3195, 2024 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-38326522

RESUMO

Although some studies conducted about the risk of cholecystectomy and cardiovascular disease, there was a limit to explaining the relationship. We investigated the short-term and long-term relationship between cholecystectomy and cardiovascular disease, and evidence using the elements of the metabolic index as an intermediate step. It was a retrospective cohort study and we used the National Health Insurance Service database of South Korea between 2002 and 2015. Finally, 5,210 patients who underwent cholecystectomy and 49,457 at 1:10 age and gender-matched controls of subjects were collected. The main results was estimated by Multivariate Cox proportional hazard regression to calculate the hazard ratio (HR) with 95% confidence interval (CI) for risk of cardiovascular disease after cholecystectomy. Regarding short-term effects of cholecystectomy, increased risk of cardiovascular disease (aHR 1.35, 95% CI 1.15-1.58) and coronary heart disease (aHR 1.77, 95% CI 1.44-2.16) were similarly seen within 2 years of surgery. When analyzing the change in metabolic risk factors, cholecystectomy was associated with a change in systolic blood pressure (adjusted mean [aMean]: 1.51, 95% CI: [- 1.50 to - 4.51]), total cholesterol (aMean - 14.14, [- 20.33 to 7.95]) and body mass index (aMean - 0.13, [- 0.37 to 0.11]). Cholecystectomy patients had elevated risk of cardiovascular disease in the short-term, possibly due to the characteristics of the patient before surgery. The association of cholecystectomy and cardiovascular disease has decreased after 2 years in patients who underwent cholecystectomy, suggesting that because of improvement of metabolic health, cholecystectomy-associated elevation of cardiovascular disease risk may be ameliorated 2 years after cholecystectomy.


Assuntos
Doenças Cardiovasculares , Humanos , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Estudos Retrospectivos , Fatores de Risco , Índice de Massa Corporal , Colecistectomia/efeitos adversos
14.
Epidemiol Health ; : e2024064, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39054628

RESUMO

Objectives: In this study, we sought to evaluate the association between smoking status and subclinical coronary atherosclerosis, as detected by coronary computed tomography angiography (CCTA), in asymptomatic individuals. Methods: We retrospectively analyzed 9,285 asymptomatic participants (mean age, 53.7±8.0 years; 6,017 [64.8%] male) with no history of coronary artery disease (CAD) who had undergone self-referred CCTA. Of these participants, 4,333 (46.7%) were considered never smokers, 2,885 (31.1%) former smokers, and 2,067 (22.3%) current smokers. We assessed the degree and characteristics of subclinical coronary atherosclerosis using CCTA, with obstructive CAD defined as a diameter stenosis of at least 50%. Results: Compared with never-smokers, former smokers exhibited no significant differences in the probabilities of obstructive CAD, any coronary plaque, calcified plaque, or mixed plaque, as determined using adjusted odds ratios (aORs; p>0.05 for all). However, the risk of non-calcified plaque was significantly higher in former smokers (aOR, 1.34; 95% confidence interval [CI], 1.00 to 1.78; p=0.048). Current smokers had significantly higher rates of obstructive CAD (aOR, 1.46; 95% CI, 1.10 to 1.96; p=0.010), any coronary plaque (aOR, 1.41; 95% CI, 1.20 to 1.65; p<0.001), calcified plaque (aOR, 1.32; 95% CI, 1.13 to 1.55; p=0.001), non-calcified plaque (aOR, 1.72; 95% CI, 1.28 to 2.32; p<0.001), and mixed plaque (aOR, 2.00; 95% CI, 1.39 to 2.86; p<0.001) compared to never smokers. Conclusion: This cross-sectional study revealed a significant association between current smoking and subclinical coronary atherosclerosis, as detected on CCTA. Additionally, former smoking demonstrated an association with non-calcified plaque, indicating elevated cardiovascular risk.

15.
Indian J Dermatol ; 68(6): 725, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38371572

RESUMO

Eccrine angiokeratomatous hamartoma is a variant of eccrine angiomatous hamartoma. Histopathologically, it shows both features of eccrine angiomatous hamartoma with components of angiokeratoma. Eccrine angiokeratomatous hamartoma is extremely rare. Eccrine angiokeratomatous hamartoma in our case co-existed with intravascular papillary endothelial hyperplasia. This is the first reported case.

16.
bioRxiv ; 2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38106048

RESUMO

The eukaryotic genome, first packed into nucleosomes of about 150 bp around the histone core, is organized into euchromatin and heterochromatin, corresponding to the A and B compartments, respectively. Here, we asked if individual nucleosomes in vivo know where to go. That is, do mono-nucleosomes by themselves contain A/B compartment information, associated with transcription activity, in their biophysical properties? We purified native mono-nucleosomes to high monodispersity and used physiological concentrations of biological polyamines to determine their condensability. The chromosomal regions known to partition into A compartments have low condensability and vice versa. In silico chromatin polymer simulations using condensability as the only input showed that biophysical information needed to form compartments is all contained in single native nucleosomes and no other factors are needed. Condensability is also strongly anticorrelated with gene expression, and especially so near the promoter region and in a cell type dependent manner. Therefore, individual nucleosomes in the promoter know whether the gene is on or off, and that information is contained in their biophysical properties. Comparison with genetic and epigenetic features suggest that nucleosome condensability is a very meaningful axis onto which to project the high dimensional cellular chromatin state. Analysis of condensability using various condensing agents including those that are protein-based suggests that genome organization principle encoded into individual nucleosomes is electrostatic in nature. Polyamine depletion in mouse T cells, by either knocking out ornithine decarboxylase (ODC) or inhibiting ODC, results in hyperpolarized condensability, suggesting that when cells cannot rely on polyamines to translate biophysical properties of nucleosomes to control gene expression and 3D genome organization, they accentuate condensability contrast, which may explain dysfunction known to occur with polyamine deficiency.

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